1 // SPDX-License-Identifier: GPL-2.0
2 
3 #include <linux/bitmap.h>
4 #include <linux/kernel.h>
5 #include <linux/module.h>
6 #include <linux/interrupt.h>
7 #include <linux/irq.h>
8 #include <linux/spinlock.h>
9 #include <linux/list.h>
10 #include <linux/device.h>
11 #include <linux/err.h>
12 #include <linux/debugfs.h>
13 #include <linux/seq_file.h>
14 #include <linux/gpio.h>
15 #include <linux/idr.h>
16 #include <linux/slab.h>
17 #include <linux/acpi.h>
18 #include <linux/gpio/driver.h>
19 #include <linux/gpio/machine.h>
20 #include <linux/pinctrl/consumer.h>
21 #include <linux/fs.h>
22 #include <linux/compat.h>
23 #include <linux/file.h>
24 #include <uapi/linux/gpio.h>
25 
26 #include "gpiolib.h"
27 #include "gpiolib-of.h"
28 #include "gpiolib-acpi.h"
29 #include "gpiolib-cdev.h"
30 #include "gpiolib-sysfs.h"
31 
32 #define CREATE_TRACE_POINTS
33 #include <trace/events/gpio.h>
34 
35 /* Implementation infrastructure for GPIO interfaces.
36  *
37  * The GPIO programming interface allows for inlining speed-critical
38  * get/set operations for common cases, so that access to SOC-integrated
39  * GPIOs can sometimes cost only an instruction or two per bit.
40  */
41 
42 
43 /* When debugging, extend minimal trust to callers and platform code.
44  * Also emit diagnostic messages that may help initial bringup, when
45  * board setup or driver bugs are most common.
46  *
47  * Otherwise, minimize overhead in what may be bitbanging codepaths.
48  */
49 #ifdef	DEBUG
50 #define	extra_checks	1
51 #else
52 #define	extra_checks	0
53 #endif
54 
55 /* Device and char device-related information */
56 static DEFINE_IDA(gpio_ida);
57 static dev_t gpio_devt;
58 #define GPIO_DEV_MAX 256 /* 256 GPIO chip devices supported */
59 static int gpio_bus_match(struct device *dev, struct device_driver *drv);
60 static struct bus_type gpio_bus_type = {
61 	.name = "gpio",
62 	.match = gpio_bus_match,
63 };
64 
65 /*
66  * Number of GPIOs to use for the fast path in set array
67  */
68 #define FASTPATH_NGPIO CONFIG_GPIOLIB_FASTPATH_LIMIT
69 
70 /* gpio_lock prevents conflicts during gpio_desc[] table updates.
71  * While any GPIO is requested, its gpio_chip is not removable;
72  * each GPIO's "requested" flag serves as a lock and refcount.
73  */
74 DEFINE_SPINLOCK(gpio_lock);
75 
76 static DEFINE_MUTEX(gpio_lookup_lock);
77 static LIST_HEAD(gpio_lookup_list);
78 LIST_HEAD(gpio_devices);
79 
80 static DEFINE_MUTEX(gpio_machine_hogs_mutex);
81 static LIST_HEAD(gpio_machine_hogs);
82 
83 static void gpiochip_free_hogs(struct gpio_chip *gc);
84 static int gpiochip_add_irqchip(struct gpio_chip *gc,
85 				struct lock_class_key *lock_key,
86 				struct lock_class_key *request_key);
87 static void gpiochip_irqchip_remove(struct gpio_chip *gc);
88 static int gpiochip_irqchip_init_hw(struct gpio_chip *gc);
89 static int gpiochip_irqchip_init_valid_mask(struct gpio_chip *gc);
90 static void gpiochip_irqchip_free_valid_mask(struct gpio_chip *gc);
91 
92 static bool gpiolib_initialized;
93 
desc_set_label(struct gpio_desc * d,const char * label)94 static inline void desc_set_label(struct gpio_desc *d, const char *label)
95 {
96 	d->label = label;
97 }
98 
99 /**
100  * gpio_to_desc - Convert a GPIO number to its descriptor
101  * @gpio: global GPIO number
102  *
103  * Returns:
104  * The GPIO descriptor associated with the given GPIO, or %NULL if no GPIO
105  * with the given number exists in the system.
106  */
gpio_to_desc(unsigned gpio)107 struct gpio_desc *gpio_to_desc(unsigned gpio)
108 {
109 	struct gpio_device *gdev;
110 	unsigned long flags;
111 
112 	spin_lock_irqsave(&gpio_lock, flags);
113 
114 	list_for_each_entry(gdev, &gpio_devices, list) {
115 		if (gdev->base <= gpio &&
116 		    gdev->base + gdev->ngpio > gpio) {
117 			spin_unlock_irqrestore(&gpio_lock, flags);
118 			return &gdev->descs[gpio - gdev->base];
119 		}
120 	}
121 
122 	spin_unlock_irqrestore(&gpio_lock, flags);
123 
124 	if (!gpio_is_valid(gpio))
125 		pr_warn("invalid GPIO %d\n", gpio);
126 
127 	return NULL;
128 }
129 EXPORT_SYMBOL_GPL(gpio_to_desc);
130 
131 /**
132  * gpiochip_get_desc - get the GPIO descriptor corresponding to the given
133  *                     hardware number for this chip
134  * @gc: GPIO chip
135  * @hwnum: hardware number of the GPIO for this chip
136  *
137  * Returns:
138  * A pointer to the GPIO descriptor or ``ERR_PTR(-EINVAL)`` if no GPIO exists
139  * in the given chip for the specified hardware number.
140  */
gpiochip_get_desc(struct gpio_chip * gc,unsigned int hwnum)141 struct gpio_desc *gpiochip_get_desc(struct gpio_chip *gc,
142 				    unsigned int hwnum)
143 {
144 	struct gpio_device *gdev = gc->gpiodev;
145 
146 	if (hwnum >= gdev->ngpio)
147 		return ERR_PTR(-EINVAL);
148 
149 	return &gdev->descs[hwnum];
150 }
151 EXPORT_SYMBOL_GPL(gpiochip_get_desc);
152 
153 /**
154  * desc_to_gpio - convert a GPIO descriptor to the integer namespace
155  * @desc: GPIO descriptor
156  *
157  * This should disappear in the future but is needed since we still
158  * use GPIO numbers for error messages and sysfs nodes.
159  *
160  * Returns:
161  * The global GPIO number for the GPIO specified by its descriptor.
162  */
desc_to_gpio(const struct gpio_desc * desc)163 int desc_to_gpio(const struct gpio_desc *desc)
164 {
165 	return desc->gdev->base + (desc - &desc->gdev->descs[0]);
166 }
167 EXPORT_SYMBOL_GPL(desc_to_gpio);
168 
169 
170 /**
171  * gpiod_to_chip - Return the GPIO chip to which a GPIO descriptor belongs
172  * @desc:	descriptor to return the chip of
173  */
gpiod_to_chip(const struct gpio_desc * desc)174 struct gpio_chip *gpiod_to_chip(const struct gpio_desc *desc)
175 {
176 	if (!desc || !desc->gdev)
177 		return NULL;
178 	return desc->gdev->chip;
179 }
180 EXPORT_SYMBOL_GPL(gpiod_to_chip);
181 
182 /* dynamic allocation of GPIOs, e.g. on a hotplugged device */
gpiochip_find_base(int ngpio)183 static int gpiochip_find_base(int ngpio)
184 {
185 	struct gpio_device *gdev;
186 	int base = ARCH_NR_GPIOS - ngpio;
187 
188 	list_for_each_entry_reverse(gdev, &gpio_devices, list) {
189 		/* found a free space? */
190 		if (gdev->base + gdev->ngpio <= base)
191 			break;
192 		/* nope, check the space right before the chip */
193 		base = gdev->base - ngpio;
194 	}
195 
196 	if (gpio_is_valid(base)) {
197 		pr_debug("%s: found new base at %d\n", __func__, base);
198 		return base;
199 	} else {
200 		pr_err("%s: cannot find free range\n", __func__);
201 		return -ENOSPC;
202 	}
203 }
204 
205 /**
206  * gpiod_get_direction - return the current direction of a GPIO
207  * @desc:	GPIO to get the direction of
208  *
209  * Returns 0 for output, 1 for input, or an error code in case of error.
210  *
211  * This function may sleep if gpiod_cansleep() is true.
212  */
gpiod_get_direction(struct gpio_desc * desc)213 int gpiod_get_direction(struct gpio_desc *desc)
214 {
215 	struct gpio_chip *gc;
216 	unsigned int offset;
217 	int ret;
218 
219 	gc = gpiod_to_chip(desc);
220 	offset = gpio_chip_hwgpio(desc);
221 
222 	/*
223 	 * Open drain emulation using input mode may incorrectly report
224 	 * input here, fix that up.
225 	 */
226 	if (test_bit(FLAG_OPEN_DRAIN, &desc->flags) &&
227 	    test_bit(FLAG_IS_OUT, &desc->flags))
228 		return 0;
229 
230 	if (!gc->get_direction)
231 		return -ENOTSUPP;
232 
233 	ret = gc->get_direction(gc, offset);
234 	if (ret < 0)
235 		return ret;
236 
237 	/* GPIOF_DIR_IN or other positive, otherwise GPIOF_DIR_OUT */
238 	if (ret > 0)
239 		ret = 1;
240 
241 	assign_bit(FLAG_IS_OUT, &desc->flags, !ret);
242 
243 	return ret;
244 }
245 EXPORT_SYMBOL_GPL(gpiod_get_direction);
246 
247 /*
248  * Add a new chip to the global chips list, keeping the list of chips sorted
249  * by range(means [base, base + ngpio - 1]) order.
250  *
251  * Return -EBUSY if the new chip overlaps with some other chip's integer
252  * space.
253  */
gpiodev_add_to_list(struct gpio_device * gdev)254 static int gpiodev_add_to_list(struct gpio_device *gdev)
255 {
256 	struct gpio_device *prev, *next;
257 
258 	if (list_empty(&gpio_devices)) {
259 		/* initial entry in list */
260 		list_add_tail(&gdev->list, &gpio_devices);
261 		return 0;
262 	}
263 
264 	next = list_first_entry(&gpio_devices, struct gpio_device, list);
265 	if (gdev->base + gdev->ngpio <= next->base) {
266 		/* add before first entry */
267 		list_add(&gdev->list, &gpio_devices);
268 		return 0;
269 	}
270 
271 	prev = list_last_entry(&gpio_devices, struct gpio_device, list);
272 	if (prev->base + prev->ngpio <= gdev->base) {
273 		/* add behind last entry */
274 		list_add_tail(&gdev->list, &gpio_devices);
275 		return 0;
276 	}
277 
278 	list_for_each_entry_safe(prev, next, &gpio_devices, list) {
279 		/* at the end of the list */
280 		if (&next->list == &gpio_devices)
281 			break;
282 
283 		/* add between prev and next */
284 		if (prev->base + prev->ngpio <= gdev->base
285 				&& gdev->base + gdev->ngpio <= next->base) {
286 			list_add(&gdev->list, &prev->list);
287 			return 0;
288 		}
289 	}
290 
291 	return -EBUSY;
292 }
293 
294 /*
295  * Convert a GPIO name to its descriptor
296  * Note that there is no guarantee that GPIO names are globally unique!
297  * Hence this function will return, if it exists, a reference to the first GPIO
298  * line found that matches the given name.
299  */
gpio_name_to_desc(const char * const name)300 static struct gpio_desc *gpio_name_to_desc(const char * const name)
301 {
302 	struct gpio_device *gdev;
303 	unsigned long flags;
304 
305 	if (!name)
306 		return NULL;
307 
308 	spin_lock_irqsave(&gpio_lock, flags);
309 
310 	list_for_each_entry(gdev, &gpio_devices, list) {
311 		struct gpio_desc *desc;
312 
313 		for_each_gpio_desc(gdev->chip, desc) {
314 			if (desc->name && !strcmp(desc->name, name)) {
315 				spin_unlock_irqrestore(&gpio_lock, flags);
316 				return desc;
317 			}
318 		}
319 	}
320 
321 	spin_unlock_irqrestore(&gpio_lock, flags);
322 
323 	return NULL;
324 }
325 
326 /*
327  * Take the names from gc->names and assign them to their GPIO descriptors.
328  * Warn if a name is already used for a GPIO line on a different GPIO chip.
329  *
330  * Note that:
331  *   1. Non-unique names are still accepted,
332  *   2. Name collisions within the same GPIO chip are not reported.
333  */
gpiochip_set_desc_names(struct gpio_chip * gc)334 static int gpiochip_set_desc_names(struct gpio_chip *gc)
335 {
336 	struct gpio_device *gdev = gc->gpiodev;
337 	int i;
338 
339 	/* First check all names if they are unique */
340 	for (i = 0; i != gc->ngpio; ++i) {
341 		struct gpio_desc *gpio;
342 
343 		gpio = gpio_name_to_desc(gc->names[i]);
344 		if (gpio)
345 			dev_warn(&gdev->dev,
346 				 "Detected name collision for GPIO name '%s'\n",
347 				 gc->names[i]);
348 	}
349 
350 	/* Then add all names to the GPIO descriptors */
351 	for (i = 0; i != gc->ngpio; ++i)
352 		gdev->descs[i].name = gc->names[i];
353 
354 	return 0;
355 }
356 
357 /*
358  * devprop_gpiochip_set_names - Set GPIO line names using device properties
359  * @chip: GPIO chip whose lines should be named, if possible
360  *
361  * Looks for device property "gpio-line-names" and if it exists assigns
362  * GPIO line names for the chip. The memory allocated for the assigned
363  * names belong to the underlying firmware node and should not be released
364  * by the caller.
365  */
devprop_gpiochip_set_names(struct gpio_chip * chip)366 static int devprop_gpiochip_set_names(struct gpio_chip *chip)
367 {
368 	struct gpio_device *gdev = chip->gpiodev;
369 	struct fwnode_handle *fwnode = dev_fwnode(&gdev->dev);
370 	const char **names;
371 	int ret, i;
372 	int count;
373 
374 	count = fwnode_property_string_array_count(fwnode, "gpio-line-names");
375 	if (count < 0)
376 		return 0;
377 
378 	/*
379 	 * When offset is set in the driver side we assume the driver internally
380 	 * is using more than one gpiochip per the same device. We have to stop
381 	 * setting friendly names if the specified ones with 'gpio-line-names'
382 	 * are less than the offset in the device itself. This means all the
383 	 * lines are not present for every single pin within all the internal
384 	 * gpiochips.
385 	 */
386 	if (count <= chip->offset) {
387 		dev_warn(&gdev->dev, "gpio-line-names too short (length %d), cannot map names for the gpiochip at offset %u\n",
388 			 count, chip->offset);
389 		return 0;
390 	}
391 
392 	names = kcalloc(count, sizeof(*names), GFP_KERNEL);
393 	if (!names)
394 		return -ENOMEM;
395 
396 	ret = fwnode_property_read_string_array(fwnode, "gpio-line-names",
397 						names, count);
398 	if (ret < 0) {
399 		dev_warn(&gdev->dev, "failed to read GPIO line names\n");
400 		kfree(names);
401 		return ret;
402 	}
403 
404 	/*
405 	 * When more that one gpiochip per device is used, 'count' can
406 	 * contain at most number gpiochips x chip->ngpio. We have to
407 	 * correctly distribute all defined lines taking into account
408 	 * chip->offset as starting point from where we will assign
409 	 * the names to pins from the 'names' array. Since property
410 	 * 'gpio-line-names' cannot contains gaps, we have to be sure
411 	 * we only assign those pins that really exists since chip->ngpio
412 	 * can be different of the chip->offset.
413 	 */
414 	count = (count > chip->offset) ? count - chip->offset : count;
415 	if (count > chip->ngpio)
416 		count = chip->ngpio;
417 
418 	for (i = 0; i < count; i++) {
419 		/*
420 		 * Allow overriding "fixed" names provided by the GPIO
421 		 * provider. The "fixed" names are more often than not
422 		 * generic and less informative than the names given in
423 		 * device properties.
424 		 */
425 		if (names[chip->offset + i] && names[chip->offset + i][0])
426 			gdev->descs[i].name = names[chip->offset + i];
427 	}
428 
429 	kfree(names);
430 
431 	return 0;
432 }
433 
gpiochip_allocate_mask(struct gpio_chip * gc)434 static unsigned long *gpiochip_allocate_mask(struct gpio_chip *gc)
435 {
436 	unsigned long *p;
437 
438 	p = bitmap_alloc(gc->ngpio, GFP_KERNEL);
439 	if (!p)
440 		return NULL;
441 
442 	/* Assume by default all GPIOs are valid */
443 	bitmap_fill(p, gc->ngpio);
444 
445 	return p;
446 }
447 
gpiochip_alloc_valid_mask(struct gpio_chip * gc)448 static int gpiochip_alloc_valid_mask(struct gpio_chip *gc)
449 {
450 	if (!(of_gpio_need_valid_mask(gc) || gc->init_valid_mask))
451 		return 0;
452 
453 	gc->valid_mask = gpiochip_allocate_mask(gc);
454 	if (!gc->valid_mask)
455 		return -ENOMEM;
456 
457 	return 0;
458 }
459 
gpiochip_init_valid_mask(struct gpio_chip * gc)460 static int gpiochip_init_valid_mask(struct gpio_chip *gc)
461 {
462 	if (gc->init_valid_mask)
463 		return gc->init_valid_mask(gc,
464 					   gc->valid_mask,
465 					   gc->ngpio);
466 
467 	return 0;
468 }
469 
gpiochip_free_valid_mask(struct gpio_chip * gc)470 static void gpiochip_free_valid_mask(struct gpio_chip *gc)
471 {
472 	bitmap_free(gc->valid_mask);
473 	gc->valid_mask = NULL;
474 }
475 
gpiochip_add_pin_ranges(struct gpio_chip * gc)476 static int gpiochip_add_pin_ranges(struct gpio_chip *gc)
477 {
478 	if (gc->add_pin_ranges)
479 		return gc->add_pin_ranges(gc);
480 
481 	return 0;
482 }
483 
gpiochip_line_is_valid(const struct gpio_chip * gc,unsigned int offset)484 bool gpiochip_line_is_valid(const struct gpio_chip *gc,
485 				unsigned int offset)
486 {
487 	/* No mask means all valid */
488 	if (likely(!gc->valid_mask))
489 		return true;
490 	return test_bit(offset, gc->valid_mask);
491 }
492 EXPORT_SYMBOL_GPL(gpiochip_line_is_valid);
493 
gpiodevice_release(struct device * dev)494 static void gpiodevice_release(struct device *dev)
495 {
496 	struct gpio_device *gdev = container_of(dev, struct gpio_device, dev);
497 	unsigned long flags;
498 
499 	spin_lock_irqsave(&gpio_lock, flags);
500 	list_del(&gdev->list);
501 	spin_unlock_irqrestore(&gpio_lock, flags);
502 
503 	ida_free(&gpio_ida, gdev->id);
504 	kfree_const(gdev->label);
505 	kfree(gdev->descs);
506 	kfree(gdev);
507 }
508 
509 #ifdef CONFIG_GPIO_CDEV
510 #define gcdev_register(gdev, devt)	gpiolib_cdev_register((gdev), (devt))
511 #define gcdev_unregister(gdev)		gpiolib_cdev_unregister((gdev))
512 #else
513 /*
514  * gpiolib_cdev_register() indirectly calls device_add(), which is still
515  * required even when cdev is not selected.
516  */
517 #define gcdev_register(gdev, devt)	device_add(&(gdev)->dev)
518 #define gcdev_unregister(gdev)		device_del(&(gdev)->dev)
519 #endif
520 
gpiochip_setup_dev(struct gpio_device * gdev)521 static int gpiochip_setup_dev(struct gpio_device *gdev)
522 {
523 	int ret;
524 
525 	ret = gcdev_register(gdev, gpio_devt);
526 	if (ret)
527 		return ret;
528 
529 	ret = gpiochip_sysfs_register(gdev);
530 	if (ret)
531 		goto err_remove_device;
532 
533 	/* From this point, the .release() function cleans up gpio_device */
534 	gdev->dev.release = gpiodevice_release;
535 	dev_dbg(&gdev->dev, "registered GPIOs %d to %d on %s\n", gdev->base,
536 		gdev->base + gdev->ngpio - 1, gdev->chip->label ? : "generic");
537 
538 	return 0;
539 
540 err_remove_device:
541 	gcdev_unregister(gdev);
542 	return ret;
543 }
544 
gpiochip_machine_hog(struct gpio_chip * gc,struct gpiod_hog * hog)545 static void gpiochip_machine_hog(struct gpio_chip *gc, struct gpiod_hog *hog)
546 {
547 	struct gpio_desc *desc;
548 	int rv;
549 
550 	desc = gpiochip_get_desc(gc, hog->chip_hwnum);
551 	if (IS_ERR(desc)) {
552 		chip_err(gc, "%s: unable to get GPIO desc: %ld\n", __func__,
553 			 PTR_ERR(desc));
554 		return;
555 	}
556 
557 	if (test_bit(FLAG_IS_HOGGED, &desc->flags))
558 		return;
559 
560 	rv = gpiod_hog(desc, hog->line_name, hog->lflags, hog->dflags);
561 	if (rv)
562 		gpiod_err(desc, "%s: unable to hog GPIO line (%s:%u): %d\n",
563 			  __func__, gc->label, hog->chip_hwnum, rv);
564 }
565 
machine_gpiochip_add(struct gpio_chip * gc)566 static void machine_gpiochip_add(struct gpio_chip *gc)
567 {
568 	struct gpiod_hog *hog;
569 
570 	mutex_lock(&gpio_machine_hogs_mutex);
571 
572 	list_for_each_entry(hog, &gpio_machine_hogs, list) {
573 		if (!strcmp(gc->label, hog->chip_label))
574 			gpiochip_machine_hog(gc, hog);
575 	}
576 
577 	mutex_unlock(&gpio_machine_hogs_mutex);
578 }
579 
gpiochip_setup_devs(void)580 static void gpiochip_setup_devs(void)
581 {
582 	struct gpio_device *gdev;
583 	int ret;
584 
585 	list_for_each_entry(gdev, &gpio_devices, list) {
586 		ret = gpiochip_setup_dev(gdev);
587 		if (ret)
588 			dev_err(&gdev->dev,
589 				"Failed to initialize gpio device (%d)\n", ret);
590 	}
591 }
592 
gpiochip_add_data_with_key(struct gpio_chip * gc,void * data,struct lock_class_key * lock_key,struct lock_class_key * request_key)593 int gpiochip_add_data_with_key(struct gpio_chip *gc, void *data,
594 			       struct lock_class_key *lock_key,
595 			       struct lock_class_key *request_key)
596 {
597 	struct fwnode_handle *fwnode = NULL;
598 	struct gpio_device *gdev;
599 	unsigned long flags;
600 	int base = gc->base;
601 	unsigned int i;
602 	int ret = 0;
603 	u32 ngpios;
604 
605 	if (gc->fwnode)
606 		fwnode = gc->fwnode;
607 	else if (gc->parent)
608 		fwnode = dev_fwnode(gc->parent);
609 
610 	/*
611 	 * First: allocate and populate the internal stat container, and
612 	 * set up the struct device.
613 	 */
614 	gdev = kzalloc(sizeof(*gdev), GFP_KERNEL);
615 	if (!gdev)
616 		return -ENOMEM;
617 	gdev->dev.bus = &gpio_bus_type;
618 	gdev->dev.parent = gc->parent;
619 	gdev->chip = gc;
620 	gc->gpiodev = gdev;
621 
622 	of_gpio_dev_init(gc, gdev);
623 	acpi_gpio_dev_init(gc, gdev);
624 
625 	/*
626 	 * Assign fwnode depending on the result of the previous calls,
627 	 * if none of them succeed, assign it to the parent's one.
628 	 */
629 	gdev->dev.fwnode = dev_fwnode(&gdev->dev) ?: fwnode;
630 
631 	gdev->id = ida_alloc(&gpio_ida, GFP_KERNEL);
632 	if (gdev->id < 0) {
633 		ret = gdev->id;
634 		goto err_free_gdev;
635 	}
636 
637 	ret = dev_set_name(&gdev->dev, GPIOCHIP_NAME "%d", gdev->id);
638 	if (ret)
639 		goto err_free_ida;
640 
641 	device_initialize(&gdev->dev);
642 	if (gc->parent && gc->parent->driver)
643 		gdev->owner = gc->parent->driver->owner;
644 	else if (gc->owner)
645 		/* TODO: remove chip->owner */
646 		gdev->owner = gc->owner;
647 	else
648 		gdev->owner = THIS_MODULE;
649 
650 	gdev->descs = kcalloc(gc->ngpio, sizeof(gdev->descs[0]), GFP_KERNEL);
651 	if (!gdev->descs) {
652 		ret = -ENOMEM;
653 		goto err_free_dev_name;
654 	}
655 
656 	/*
657 	 * Try the device properties if the driver didn't supply the number
658 	 * of GPIO lines.
659 	 */
660 	if (gc->ngpio == 0) {
661 		ret = device_property_read_u32(&gdev->dev, "ngpios", &ngpios);
662 		if (ret == -ENODATA)
663 			/*
664 			 * -ENODATA means that there is no property found and
665 			 * we want to issue the error message to the user.
666 			 * Besides that, we want to return different error code
667 			 * to state that supplied value is not valid.
668 			 */
669 			ngpios = 0;
670 		else if (ret)
671 			goto err_free_descs;
672 
673 		gc->ngpio = ngpios;
674 	}
675 
676 	if (gc->ngpio == 0) {
677 		chip_err(gc, "tried to insert a GPIO chip with zero lines\n");
678 		ret = -EINVAL;
679 		goto err_free_descs;
680 	}
681 
682 	if (gc->ngpio > FASTPATH_NGPIO)
683 		chip_warn(gc, "line cnt %u is greater than fast path cnt %u\n",
684 			  gc->ngpio, FASTPATH_NGPIO);
685 
686 	gdev->label = kstrdup_const(gc->label ?: "unknown", GFP_KERNEL);
687 	if (!gdev->label) {
688 		ret = -ENOMEM;
689 		goto err_free_descs;
690 	}
691 
692 	gdev->ngpio = gc->ngpio;
693 	gdev->data = data;
694 
695 	spin_lock_irqsave(&gpio_lock, flags);
696 
697 	/*
698 	 * TODO: this allocates a Linux GPIO number base in the global
699 	 * GPIO numberspace for this chip. In the long run we want to
700 	 * get *rid* of this numberspace and use only descriptors, but
701 	 * it may be a pipe dream. It will not happen before we get rid
702 	 * of the sysfs interface anyways.
703 	 */
704 	if (base < 0) {
705 		base = gpiochip_find_base(gc->ngpio);
706 		if (base < 0) {
707 			ret = base;
708 			spin_unlock_irqrestore(&gpio_lock, flags);
709 			goto err_free_label;
710 		}
711 		/*
712 		 * TODO: it should not be necessary to reflect the assigned
713 		 * base outside of the GPIO subsystem. Go over drivers and
714 		 * see if anyone makes use of this, else drop this and assign
715 		 * a poison instead.
716 		 */
717 		gc->base = base;
718 	}
719 	gdev->base = base;
720 
721 	ret = gpiodev_add_to_list(gdev);
722 	if (ret) {
723 		spin_unlock_irqrestore(&gpio_lock, flags);
724 		chip_err(gc, "GPIO integer space overlap, cannot add chip\n");
725 		goto err_free_label;
726 	}
727 
728 	for (i = 0; i < gc->ngpio; i++)
729 		gdev->descs[i].gdev = gdev;
730 
731 	spin_unlock_irqrestore(&gpio_lock, flags);
732 
733 	BLOCKING_INIT_NOTIFIER_HEAD(&gdev->notifier);
734 
735 #ifdef CONFIG_PINCTRL
736 	INIT_LIST_HEAD(&gdev->pin_ranges);
737 #endif
738 
739 	if (gc->names) {
740 		ret = gpiochip_set_desc_names(gc);
741 		if (ret)
742 			goto err_remove_from_list;
743 	}
744 	ret = devprop_gpiochip_set_names(gc);
745 	if (ret)
746 		goto err_remove_from_list;
747 
748 	ret = gpiochip_alloc_valid_mask(gc);
749 	if (ret)
750 		goto err_remove_from_list;
751 
752 	ret = of_gpiochip_add(gc);
753 	if (ret)
754 		goto err_free_gpiochip_mask;
755 
756 	ret = gpiochip_init_valid_mask(gc);
757 	if (ret)
758 		goto err_remove_of_chip;
759 
760 	for (i = 0; i < gc->ngpio; i++) {
761 		struct gpio_desc *desc = &gdev->descs[i];
762 
763 		if (gc->get_direction && gpiochip_line_is_valid(gc, i)) {
764 			assign_bit(FLAG_IS_OUT,
765 				   &desc->flags, !gc->get_direction(gc, i));
766 		} else {
767 			assign_bit(FLAG_IS_OUT,
768 				   &desc->flags, !gc->direction_input);
769 		}
770 	}
771 
772 	ret = gpiochip_add_pin_ranges(gc);
773 	if (ret)
774 		goto err_remove_of_chip;
775 
776 	acpi_gpiochip_add(gc);
777 
778 	machine_gpiochip_add(gc);
779 
780 	ret = gpiochip_irqchip_init_valid_mask(gc);
781 	if (ret)
782 		goto err_remove_acpi_chip;
783 
784 	ret = gpiochip_irqchip_init_hw(gc);
785 	if (ret)
786 		goto err_remove_acpi_chip;
787 
788 	ret = gpiochip_add_irqchip(gc, lock_key, request_key);
789 	if (ret)
790 		goto err_remove_irqchip_mask;
791 
792 	/*
793 	 * By first adding the chardev, and then adding the device,
794 	 * we get a device node entry in sysfs under
795 	 * /sys/bus/gpio/devices/gpiochipN/dev that can be used for
796 	 * coldplug of device nodes and other udev business.
797 	 * We can do this only if gpiolib has been initialized.
798 	 * Otherwise, defer until later.
799 	 */
800 	if (gpiolib_initialized) {
801 		ret = gpiochip_setup_dev(gdev);
802 		if (ret)
803 			goto err_remove_irqchip;
804 	}
805 	return 0;
806 
807 err_remove_irqchip:
808 	gpiochip_irqchip_remove(gc);
809 err_remove_irqchip_mask:
810 	gpiochip_irqchip_free_valid_mask(gc);
811 err_remove_acpi_chip:
812 	acpi_gpiochip_remove(gc);
813 err_remove_of_chip:
814 	gpiochip_free_hogs(gc);
815 	of_gpiochip_remove(gc);
816 err_free_gpiochip_mask:
817 	gpiochip_remove_pin_ranges(gc);
818 	gpiochip_free_valid_mask(gc);
819 err_remove_from_list:
820 	spin_lock_irqsave(&gpio_lock, flags);
821 	list_del(&gdev->list);
822 	spin_unlock_irqrestore(&gpio_lock, flags);
823 err_free_label:
824 	kfree_const(gdev->label);
825 err_free_descs:
826 	kfree(gdev->descs);
827 err_free_dev_name:
828 	kfree(dev_name(&gdev->dev));
829 err_free_ida:
830 	ida_free(&gpio_ida, gdev->id);
831 err_free_gdev:
832 	/* failures here can mean systems won't boot... */
833 	if (ret != -EPROBE_DEFER) {
834 		pr_err("%s: GPIOs %d..%d (%s) failed to register, %d\n", __func__,
835 		       gdev->base, gdev->base + gdev->ngpio - 1,
836 		       gc->label ? : "generic", ret);
837 	}
838 	kfree(gdev);
839 	return ret;
840 }
841 EXPORT_SYMBOL_GPL(gpiochip_add_data_with_key);
842 
843 /**
844  * gpiochip_get_data() - get per-subdriver data for the chip
845  * @gc: GPIO chip
846  *
847  * Returns:
848  * The per-subdriver data for the chip.
849  */
gpiochip_get_data(struct gpio_chip * gc)850 void *gpiochip_get_data(struct gpio_chip *gc)
851 {
852 	return gc->gpiodev->data;
853 }
854 EXPORT_SYMBOL_GPL(gpiochip_get_data);
855 
856 /**
857  * gpiochip_remove() - unregister a gpio_chip
858  * @gc: the chip to unregister
859  *
860  * A gpio_chip with any GPIOs still requested may not be removed.
861  */
gpiochip_remove(struct gpio_chip * gc)862 void gpiochip_remove(struct gpio_chip *gc)
863 {
864 	struct gpio_device *gdev = gc->gpiodev;
865 	unsigned long	flags;
866 	unsigned int	i;
867 
868 	/* FIXME: should the legacy sysfs handling be moved to gpio_device? */
869 	gpiochip_sysfs_unregister(gdev);
870 	gpiochip_free_hogs(gc);
871 	/* Numb the device, cancelling all outstanding operations */
872 	gdev->chip = NULL;
873 	gpiochip_irqchip_remove(gc);
874 	acpi_gpiochip_remove(gc);
875 	of_gpiochip_remove(gc);
876 	gpiochip_remove_pin_ranges(gc);
877 	gpiochip_free_valid_mask(gc);
878 	/*
879 	 * We accept no more calls into the driver from this point, so
880 	 * NULL the driver data pointer
881 	 */
882 	gdev->data = NULL;
883 
884 	spin_lock_irqsave(&gpio_lock, flags);
885 	for (i = 0; i < gdev->ngpio; i++) {
886 		if (gpiochip_is_requested(gc, i))
887 			break;
888 	}
889 	spin_unlock_irqrestore(&gpio_lock, flags);
890 
891 	if (i != gdev->ngpio)
892 		dev_crit(&gdev->dev,
893 			 "REMOVING GPIOCHIP WITH GPIOS STILL REQUESTED\n");
894 
895 	/*
896 	 * The gpiochip side puts its use of the device to rest here:
897 	 * if there are no userspace clients, the chardev and device will
898 	 * be removed, else it will be dangling until the last user is
899 	 * gone.
900 	 */
901 	gcdev_unregister(gdev);
902 	put_device(&gdev->dev);
903 }
904 EXPORT_SYMBOL_GPL(gpiochip_remove);
905 
906 /**
907  * gpiochip_find() - iterator for locating a specific gpio_chip
908  * @data: data to pass to match function
909  * @match: Callback function to check gpio_chip
910  *
911  * Similar to bus_find_device.  It returns a reference to a gpio_chip as
912  * determined by a user supplied @match callback.  The callback should return
913  * 0 if the device doesn't match and non-zero if it does.  If the callback is
914  * non-zero, this function will return to the caller and not iterate over any
915  * more gpio_chips.
916  */
gpiochip_find(void * data,int (* match)(struct gpio_chip * gc,void * data))917 struct gpio_chip *gpiochip_find(void *data,
918 				int (*match)(struct gpio_chip *gc,
919 					     void *data))
920 {
921 	struct gpio_device *gdev;
922 	struct gpio_chip *gc = NULL;
923 	unsigned long flags;
924 
925 	spin_lock_irqsave(&gpio_lock, flags);
926 	list_for_each_entry(gdev, &gpio_devices, list)
927 		if (gdev->chip && match(gdev->chip, data)) {
928 			gc = gdev->chip;
929 			break;
930 		}
931 
932 	spin_unlock_irqrestore(&gpio_lock, flags);
933 
934 	return gc;
935 }
936 EXPORT_SYMBOL_GPL(gpiochip_find);
937 
gpiochip_match_name(struct gpio_chip * gc,void * data)938 static int gpiochip_match_name(struct gpio_chip *gc, void *data)
939 {
940 	const char *name = data;
941 
942 	return !strcmp(gc->label, name);
943 }
944 
find_chip_by_name(const char * name)945 static struct gpio_chip *find_chip_by_name(const char *name)
946 {
947 	return gpiochip_find((void *)name, gpiochip_match_name);
948 }
949 
950 #ifdef CONFIG_GPIOLIB_IRQCHIP
951 
952 /*
953  * The following is irqchip helper code for gpiochips.
954  */
955 
gpiochip_irqchip_init_hw(struct gpio_chip * gc)956 static int gpiochip_irqchip_init_hw(struct gpio_chip *gc)
957 {
958 	struct gpio_irq_chip *girq = &gc->irq;
959 
960 	if (!girq->init_hw)
961 		return 0;
962 
963 	return girq->init_hw(gc);
964 }
965 
gpiochip_irqchip_init_valid_mask(struct gpio_chip * gc)966 static int gpiochip_irqchip_init_valid_mask(struct gpio_chip *gc)
967 {
968 	struct gpio_irq_chip *girq = &gc->irq;
969 
970 	if (!girq->init_valid_mask)
971 		return 0;
972 
973 	girq->valid_mask = gpiochip_allocate_mask(gc);
974 	if (!girq->valid_mask)
975 		return -ENOMEM;
976 
977 	girq->init_valid_mask(gc, girq->valid_mask, gc->ngpio);
978 
979 	return 0;
980 }
981 
gpiochip_irqchip_free_valid_mask(struct gpio_chip * gc)982 static void gpiochip_irqchip_free_valid_mask(struct gpio_chip *gc)
983 {
984 	bitmap_free(gc->irq.valid_mask);
985 	gc->irq.valid_mask = NULL;
986 }
987 
gpiochip_irqchip_irq_valid(const struct gpio_chip * gc,unsigned int offset)988 bool gpiochip_irqchip_irq_valid(const struct gpio_chip *gc,
989 				unsigned int offset)
990 {
991 	if (!gpiochip_line_is_valid(gc, offset))
992 		return false;
993 	/* No mask means all valid */
994 	if (likely(!gc->irq.valid_mask))
995 		return true;
996 	return test_bit(offset, gc->irq.valid_mask);
997 }
998 EXPORT_SYMBOL_GPL(gpiochip_irqchip_irq_valid);
999 
1000 #ifdef CONFIG_IRQ_DOMAIN_HIERARCHY
1001 
1002 /**
1003  * gpiochip_set_hierarchical_irqchip() - connects a hierarchical irqchip
1004  * to a gpiochip
1005  * @gc: the gpiochip to set the irqchip hierarchical handler to
1006  * @irqchip: the irqchip to handle this level of the hierarchy, the interrupt
1007  * will then percolate up to the parent
1008  */
gpiochip_set_hierarchical_irqchip(struct gpio_chip * gc,struct irq_chip * irqchip)1009 static void gpiochip_set_hierarchical_irqchip(struct gpio_chip *gc,
1010 					      struct irq_chip *irqchip)
1011 {
1012 	/* DT will deal with mapping each IRQ as we go along */
1013 	if (is_of_node(gc->irq.fwnode))
1014 		return;
1015 
1016 	/*
1017 	 * This is for legacy and boardfile "irqchip" fwnodes: allocate
1018 	 * irqs upfront instead of dynamically since we don't have the
1019 	 * dynamic type of allocation that hardware description languages
1020 	 * provide. Once all GPIO drivers using board files are gone from
1021 	 * the kernel we can delete this code, but for a transitional period
1022 	 * it is necessary to keep this around.
1023 	 */
1024 	if (is_fwnode_irqchip(gc->irq.fwnode)) {
1025 		int i;
1026 		int ret;
1027 
1028 		for (i = 0; i < gc->ngpio; i++) {
1029 			struct irq_fwspec fwspec;
1030 			unsigned int parent_hwirq;
1031 			unsigned int parent_type;
1032 			struct gpio_irq_chip *girq = &gc->irq;
1033 
1034 			/*
1035 			 * We call the child to parent translation function
1036 			 * only to check if the child IRQ is valid or not.
1037 			 * Just pick the rising edge type here as that is what
1038 			 * we likely need to support.
1039 			 */
1040 			ret = girq->child_to_parent_hwirq(gc, i,
1041 							  IRQ_TYPE_EDGE_RISING,
1042 							  &parent_hwirq,
1043 							  &parent_type);
1044 			if (ret) {
1045 				chip_err(gc, "skip set-up on hwirq %d\n",
1046 					 i);
1047 				continue;
1048 			}
1049 
1050 			fwspec.fwnode = gc->irq.fwnode;
1051 			/* This is the hwirq for the GPIO line side of things */
1052 			fwspec.param[0] = girq->child_offset_to_irq(gc, i);
1053 			/* Just pick something */
1054 			fwspec.param[1] = IRQ_TYPE_EDGE_RISING;
1055 			fwspec.param_count = 2;
1056 			ret = __irq_domain_alloc_irqs(gc->irq.domain,
1057 						      /* just pick something */
1058 						      -1,
1059 						      1,
1060 						      NUMA_NO_NODE,
1061 						      &fwspec,
1062 						      false,
1063 						      NULL);
1064 			if (ret < 0) {
1065 				chip_err(gc,
1066 					 "can not allocate irq for GPIO line %d parent hwirq %d in hierarchy domain: %d\n",
1067 					 i, parent_hwirq,
1068 					 ret);
1069 			}
1070 		}
1071 	}
1072 
1073 	chip_err(gc, "%s unknown fwnode type proceed anyway\n", __func__);
1074 
1075 	return;
1076 }
1077 
gpiochip_hierarchy_irq_domain_translate(struct irq_domain * d,struct irq_fwspec * fwspec,unsigned long * hwirq,unsigned int * type)1078 static int gpiochip_hierarchy_irq_domain_translate(struct irq_domain *d,
1079 						   struct irq_fwspec *fwspec,
1080 						   unsigned long *hwirq,
1081 						   unsigned int *type)
1082 {
1083 	/* We support standard DT translation */
1084 	if (is_of_node(fwspec->fwnode) && fwspec->param_count == 2) {
1085 		return irq_domain_translate_twocell(d, fwspec, hwirq, type);
1086 	}
1087 
1088 	/* This is for board files and others not using DT */
1089 	if (is_fwnode_irqchip(fwspec->fwnode)) {
1090 		int ret;
1091 
1092 		ret = irq_domain_translate_twocell(d, fwspec, hwirq, type);
1093 		if (ret)
1094 			return ret;
1095 		WARN_ON(*type == IRQ_TYPE_NONE);
1096 		return 0;
1097 	}
1098 	return -EINVAL;
1099 }
1100 
gpiochip_hierarchy_irq_domain_alloc(struct irq_domain * d,unsigned int irq,unsigned int nr_irqs,void * data)1101 static int gpiochip_hierarchy_irq_domain_alloc(struct irq_domain *d,
1102 					       unsigned int irq,
1103 					       unsigned int nr_irqs,
1104 					       void *data)
1105 {
1106 	struct gpio_chip *gc = d->host_data;
1107 	irq_hw_number_t hwirq;
1108 	unsigned int type = IRQ_TYPE_NONE;
1109 	struct irq_fwspec *fwspec = data;
1110 	void *parent_arg;
1111 	unsigned int parent_hwirq;
1112 	unsigned int parent_type;
1113 	struct gpio_irq_chip *girq = &gc->irq;
1114 	int ret;
1115 
1116 	/*
1117 	 * The nr_irqs parameter is always one except for PCI multi-MSI
1118 	 * so this should not happen.
1119 	 */
1120 	WARN_ON(nr_irqs != 1);
1121 
1122 	ret = gc->irq.child_irq_domain_ops.translate(d, fwspec, &hwirq, &type);
1123 	if (ret)
1124 		return ret;
1125 
1126 	chip_dbg(gc, "allocate IRQ %d, hwirq %lu\n", irq,  hwirq);
1127 
1128 	ret = girq->child_to_parent_hwirq(gc, hwirq, type,
1129 					  &parent_hwirq, &parent_type);
1130 	if (ret) {
1131 		chip_err(gc, "can't look up hwirq %lu\n", hwirq);
1132 		return ret;
1133 	}
1134 	chip_dbg(gc, "found parent hwirq %u\n", parent_hwirq);
1135 
1136 	/*
1137 	 * We set handle_bad_irq because the .set_type() should
1138 	 * always be invoked and set the right type of handler.
1139 	 */
1140 	irq_domain_set_info(d,
1141 			    irq,
1142 			    hwirq,
1143 			    gc->irq.chip,
1144 			    gc,
1145 			    girq->handler,
1146 			    NULL, NULL);
1147 	irq_set_probe(irq);
1148 
1149 	/* This parent only handles asserted level IRQs */
1150 	parent_arg = girq->populate_parent_alloc_arg(gc, parent_hwirq, parent_type);
1151 	if (!parent_arg)
1152 		return -ENOMEM;
1153 
1154 	chip_dbg(gc, "alloc_irqs_parent for %d parent hwirq %d\n",
1155 		  irq, parent_hwirq);
1156 	irq_set_lockdep_class(irq, gc->irq.lock_key, gc->irq.request_key);
1157 	ret = irq_domain_alloc_irqs_parent(d, irq, 1, parent_arg);
1158 	/*
1159 	 * If the parent irqdomain is msi, the interrupts have already
1160 	 * been allocated, so the EEXIST is good.
1161 	 */
1162 	if (irq_domain_is_msi(d->parent) && (ret == -EEXIST))
1163 		ret = 0;
1164 	if (ret)
1165 		chip_err(gc,
1166 			 "failed to allocate parent hwirq %d for hwirq %lu\n",
1167 			 parent_hwirq, hwirq);
1168 
1169 	kfree(parent_arg);
1170 	return ret;
1171 }
1172 
gpiochip_child_offset_to_irq_noop(struct gpio_chip * gc,unsigned int offset)1173 static unsigned int gpiochip_child_offset_to_irq_noop(struct gpio_chip *gc,
1174 						      unsigned int offset)
1175 {
1176 	return offset;
1177 }
1178 
gpiochip_hierarchy_setup_domain_ops(struct irq_domain_ops * ops)1179 static void gpiochip_hierarchy_setup_domain_ops(struct irq_domain_ops *ops)
1180 {
1181 	ops->activate = gpiochip_irq_domain_activate;
1182 	ops->deactivate = gpiochip_irq_domain_deactivate;
1183 	ops->alloc = gpiochip_hierarchy_irq_domain_alloc;
1184 	ops->free = irq_domain_free_irqs_common;
1185 
1186 	/*
1187 	 * We only allow overriding the translate() function for
1188 	 * hierarchical chips, and this should only be done if the user
1189 	 * really need something other than 1:1 translation.
1190 	 */
1191 	if (!ops->translate)
1192 		ops->translate = gpiochip_hierarchy_irq_domain_translate;
1193 }
1194 
gpiochip_hierarchy_add_domain(struct gpio_chip * gc)1195 static int gpiochip_hierarchy_add_domain(struct gpio_chip *gc)
1196 {
1197 	if (!gc->irq.child_to_parent_hwirq ||
1198 	    !gc->irq.fwnode) {
1199 		chip_err(gc, "missing irqdomain vital data\n");
1200 		return -EINVAL;
1201 	}
1202 
1203 	if (!gc->irq.child_offset_to_irq)
1204 		gc->irq.child_offset_to_irq = gpiochip_child_offset_to_irq_noop;
1205 
1206 	if (!gc->irq.populate_parent_alloc_arg)
1207 		gc->irq.populate_parent_alloc_arg =
1208 			gpiochip_populate_parent_fwspec_twocell;
1209 
1210 	gpiochip_hierarchy_setup_domain_ops(&gc->irq.child_irq_domain_ops);
1211 
1212 	gc->irq.domain = irq_domain_create_hierarchy(
1213 		gc->irq.parent_domain,
1214 		0,
1215 		gc->ngpio,
1216 		gc->irq.fwnode,
1217 		&gc->irq.child_irq_domain_ops,
1218 		gc);
1219 
1220 	if (!gc->irq.domain)
1221 		return -ENOMEM;
1222 
1223 	gpiochip_set_hierarchical_irqchip(gc, gc->irq.chip);
1224 
1225 	return 0;
1226 }
1227 
gpiochip_hierarchy_is_hierarchical(struct gpio_chip * gc)1228 static bool gpiochip_hierarchy_is_hierarchical(struct gpio_chip *gc)
1229 {
1230 	return !!gc->irq.parent_domain;
1231 }
1232 
gpiochip_populate_parent_fwspec_twocell(struct gpio_chip * gc,unsigned int parent_hwirq,unsigned int parent_type)1233 void *gpiochip_populate_parent_fwspec_twocell(struct gpio_chip *gc,
1234 					     unsigned int parent_hwirq,
1235 					     unsigned int parent_type)
1236 {
1237 	struct irq_fwspec *fwspec;
1238 
1239 	fwspec = kmalloc(sizeof(*fwspec), GFP_KERNEL);
1240 	if (!fwspec)
1241 		return NULL;
1242 
1243 	fwspec->fwnode = gc->irq.parent_domain->fwnode;
1244 	fwspec->param_count = 2;
1245 	fwspec->param[0] = parent_hwirq;
1246 	fwspec->param[1] = parent_type;
1247 
1248 	return fwspec;
1249 }
1250 EXPORT_SYMBOL_GPL(gpiochip_populate_parent_fwspec_twocell);
1251 
gpiochip_populate_parent_fwspec_fourcell(struct gpio_chip * gc,unsigned int parent_hwirq,unsigned int parent_type)1252 void *gpiochip_populate_parent_fwspec_fourcell(struct gpio_chip *gc,
1253 					      unsigned int parent_hwirq,
1254 					      unsigned int parent_type)
1255 {
1256 	struct irq_fwspec *fwspec;
1257 
1258 	fwspec = kmalloc(sizeof(*fwspec), GFP_KERNEL);
1259 	if (!fwspec)
1260 		return NULL;
1261 
1262 	fwspec->fwnode = gc->irq.parent_domain->fwnode;
1263 	fwspec->param_count = 4;
1264 	fwspec->param[0] = 0;
1265 	fwspec->param[1] = parent_hwirq;
1266 	fwspec->param[2] = 0;
1267 	fwspec->param[3] = parent_type;
1268 
1269 	return fwspec;
1270 }
1271 EXPORT_SYMBOL_GPL(gpiochip_populate_parent_fwspec_fourcell);
1272 
1273 #else
1274 
gpiochip_hierarchy_add_domain(struct gpio_chip * gc)1275 static int gpiochip_hierarchy_add_domain(struct gpio_chip *gc)
1276 {
1277 	return -EINVAL;
1278 }
1279 
gpiochip_hierarchy_is_hierarchical(struct gpio_chip * gc)1280 static bool gpiochip_hierarchy_is_hierarchical(struct gpio_chip *gc)
1281 {
1282 	return false;
1283 }
1284 
1285 #endif /* CONFIG_IRQ_DOMAIN_HIERARCHY */
1286 
1287 /**
1288  * gpiochip_irq_map() - maps an IRQ into a GPIO irqchip
1289  * @d: the irqdomain used by this irqchip
1290  * @irq: the global irq number used by this GPIO irqchip irq
1291  * @hwirq: the local IRQ/GPIO line offset on this gpiochip
1292  *
1293  * This function will set up the mapping for a certain IRQ line on a
1294  * gpiochip by assigning the gpiochip as chip data, and using the irqchip
1295  * stored inside the gpiochip.
1296  */
gpiochip_irq_map(struct irq_domain * d,unsigned int irq,irq_hw_number_t hwirq)1297 int gpiochip_irq_map(struct irq_domain *d, unsigned int irq,
1298 		     irq_hw_number_t hwirq)
1299 {
1300 	struct gpio_chip *gc = d->host_data;
1301 	int ret = 0;
1302 
1303 	if (!gpiochip_irqchip_irq_valid(gc, hwirq))
1304 		return -ENXIO;
1305 
1306 	irq_set_chip_data(irq, gc);
1307 	/*
1308 	 * This lock class tells lockdep that GPIO irqs are in a different
1309 	 * category than their parents, so it won't report false recursion.
1310 	 */
1311 	irq_set_lockdep_class(irq, gc->irq.lock_key, gc->irq.request_key);
1312 	irq_set_chip_and_handler(irq, gc->irq.chip, gc->irq.handler);
1313 	/* Chips that use nested thread handlers have them marked */
1314 	if (gc->irq.threaded)
1315 		irq_set_nested_thread(irq, 1);
1316 	irq_set_noprobe(irq);
1317 
1318 	if (gc->irq.num_parents == 1)
1319 		ret = irq_set_parent(irq, gc->irq.parents[0]);
1320 	else if (gc->irq.map)
1321 		ret = irq_set_parent(irq, gc->irq.map[hwirq]);
1322 
1323 	if (ret < 0)
1324 		return ret;
1325 
1326 	/*
1327 	 * No set-up of the hardware will happen if IRQ_TYPE_NONE
1328 	 * is passed as default type.
1329 	 */
1330 	if (gc->irq.default_type != IRQ_TYPE_NONE)
1331 		irq_set_irq_type(irq, gc->irq.default_type);
1332 
1333 	return 0;
1334 }
1335 EXPORT_SYMBOL_GPL(gpiochip_irq_map);
1336 
gpiochip_irq_unmap(struct irq_domain * d,unsigned int irq)1337 void gpiochip_irq_unmap(struct irq_domain *d, unsigned int irq)
1338 {
1339 	struct gpio_chip *gc = d->host_data;
1340 
1341 	if (gc->irq.threaded)
1342 		irq_set_nested_thread(irq, 0);
1343 	irq_set_chip_and_handler(irq, NULL, NULL);
1344 	irq_set_chip_data(irq, NULL);
1345 }
1346 EXPORT_SYMBOL_GPL(gpiochip_irq_unmap);
1347 
1348 static const struct irq_domain_ops gpiochip_domain_ops = {
1349 	.map	= gpiochip_irq_map,
1350 	.unmap	= gpiochip_irq_unmap,
1351 	/* Virtually all GPIO irqchips are twocell:ed */
1352 	.xlate	= irq_domain_xlate_twocell,
1353 };
1354 
1355 /*
1356  * TODO: move these activate/deactivate in under the hierarchicial
1357  * irqchip implementation as static once SPMI and SSBI (all external
1358  * users) are phased over.
1359  */
1360 /**
1361  * gpiochip_irq_domain_activate() - Lock a GPIO to be used as an IRQ
1362  * @domain: The IRQ domain used by this IRQ chip
1363  * @data: Outermost irq_data associated with the IRQ
1364  * @reserve: If set, only reserve an interrupt vector instead of assigning one
1365  *
1366  * This function is a wrapper that calls gpiochip_lock_as_irq() and is to be
1367  * used as the activate function for the &struct irq_domain_ops. The host_data
1368  * for the IRQ domain must be the &struct gpio_chip.
1369  */
gpiochip_irq_domain_activate(struct irq_domain * domain,struct irq_data * data,bool reserve)1370 int gpiochip_irq_domain_activate(struct irq_domain *domain,
1371 				 struct irq_data *data, bool reserve)
1372 {
1373 	struct gpio_chip *gc = domain->host_data;
1374 
1375 	return gpiochip_lock_as_irq(gc, data->hwirq);
1376 }
1377 EXPORT_SYMBOL_GPL(gpiochip_irq_domain_activate);
1378 
1379 /**
1380  * gpiochip_irq_domain_deactivate() - Unlock a GPIO used as an IRQ
1381  * @domain: The IRQ domain used by this IRQ chip
1382  * @data: Outermost irq_data associated with the IRQ
1383  *
1384  * This function is a wrapper that will call gpiochip_unlock_as_irq() and is to
1385  * be used as the deactivate function for the &struct irq_domain_ops. The
1386  * host_data for the IRQ domain must be the &struct gpio_chip.
1387  */
gpiochip_irq_domain_deactivate(struct irq_domain * domain,struct irq_data * data)1388 void gpiochip_irq_domain_deactivate(struct irq_domain *domain,
1389 				    struct irq_data *data)
1390 {
1391 	struct gpio_chip *gc = domain->host_data;
1392 
1393 	return gpiochip_unlock_as_irq(gc, data->hwirq);
1394 }
1395 EXPORT_SYMBOL_GPL(gpiochip_irq_domain_deactivate);
1396 
gpiochip_to_irq(struct gpio_chip * gc,unsigned int offset)1397 static int gpiochip_to_irq(struct gpio_chip *gc, unsigned int offset)
1398 {
1399 	struct irq_domain *domain = gc->irq.domain;
1400 
1401 #ifdef CONFIG_GPIOLIB_IRQCHIP
1402 	/*
1403 	 * Avoid race condition with other code, which tries to lookup
1404 	 * an IRQ before the irqchip has been properly registered,
1405 	 * i.e. while gpiochip is still being brought up.
1406 	 */
1407 	if (!gc->irq.initialized)
1408 		return -EPROBE_DEFER;
1409 #endif
1410 
1411 	if (!gpiochip_irqchip_irq_valid(gc, offset))
1412 		return -ENXIO;
1413 
1414 #ifdef CONFIG_IRQ_DOMAIN_HIERARCHY
1415 	if (irq_domain_is_hierarchy(domain)) {
1416 		struct irq_fwspec spec;
1417 
1418 		spec.fwnode = domain->fwnode;
1419 		spec.param_count = 2;
1420 		spec.param[0] = gc->irq.child_offset_to_irq(gc, offset);
1421 		spec.param[1] = IRQ_TYPE_NONE;
1422 
1423 		return irq_create_fwspec_mapping(&spec);
1424 	}
1425 #endif
1426 
1427 	return irq_create_mapping(domain, offset);
1428 }
1429 
gpiochip_irq_reqres(struct irq_data * d)1430 int gpiochip_irq_reqres(struct irq_data *d)
1431 {
1432 	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
1433 
1434 	return gpiochip_reqres_irq(gc, d->hwirq);
1435 }
1436 EXPORT_SYMBOL(gpiochip_irq_reqres);
1437 
gpiochip_irq_relres(struct irq_data * d)1438 void gpiochip_irq_relres(struct irq_data *d)
1439 {
1440 	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
1441 
1442 	gpiochip_relres_irq(gc, d->hwirq);
1443 }
1444 EXPORT_SYMBOL(gpiochip_irq_relres);
1445 
gpiochip_irq_mask(struct irq_data * d)1446 static void gpiochip_irq_mask(struct irq_data *d)
1447 {
1448 	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
1449 
1450 	if (gc->irq.irq_mask)
1451 		gc->irq.irq_mask(d);
1452 	gpiochip_disable_irq(gc, d->hwirq);
1453 }
1454 
gpiochip_irq_unmask(struct irq_data * d)1455 static void gpiochip_irq_unmask(struct irq_data *d)
1456 {
1457 	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
1458 
1459 	gpiochip_enable_irq(gc, d->hwirq);
1460 	if (gc->irq.irq_unmask)
1461 		gc->irq.irq_unmask(d);
1462 }
1463 
gpiochip_irq_enable(struct irq_data * d)1464 static void gpiochip_irq_enable(struct irq_data *d)
1465 {
1466 	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
1467 
1468 	gpiochip_enable_irq(gc, d->hwirq);
1469 	gc->irq.irq_enable(d);
1470 }
1471 
gpiochip_irq_disable(struct irq_data * d)1472 static void gpiochip_irq_disable(struct irq_data *d)
1473 {
1474 	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
1475 
1476 	gc->irq.irq_disable(d);
1477 	gpiochip_disable_irq(gc, d->hwirq);
1478 }
1479 
gpiochip_set_irq_hooks(struct gpio_chip * gc)1480 static void gpiochip_set_irq_hooks(struct gpio_chip *gc)
1481 {
1482 	struct irq_chip *irqchip = gc->irq.chip;
1483 
1484 	if (irqchip->flags & IRQCHIP_IMMUTABLE)
1485 		return;
1486 
1487 	chip_warn(gc, "not an immutable chip, please consider fixing it!\n");
1488 
1489 	if (!irqchip->irq_request_resources &&
1490 	    !irqchip->irq_release_resources) {
1491 		irqchip->irq_request_resources = gpiochip_irq_reqres;
1492 		irqchip->irq_release_resources = gpiochip_irq_relres;
1493 	}
1494 	if (WARN_ON(gc->irq.irq_enable))
1495 		return;
1496 	/* Check if the irqchip already has this hook... */
1497 	if (irqchip->irq_enable == gpiochip_irq_enable ||
1498 		irqchip->irq_mask == gpiochip_irq_mask) {
1499 		/*
1500 		 * ...and if so, give a gentle warning that this is bad
1501 		 * practice.
1502 		 */
1503 		chip_info(gc,
1504 			  "detected irqchip that is shared with multiple gpiochips: please fix the driver.\n");
1505 		return;
1506 	}
1507 
1508 	if (irqchip->irq_disable) {
1509 		gc->irq.irq_disable = irqchip->irq_disable;
1510 		irqchip->irq_disable = gpiochip_irq_disable;
1511 	} else {
1512 		gc->irq.irq_mask = irqchip->irq_mask;
1513 		irqchip->irq_mask = gpiochip_irq_mask;
1514 	}
1515 
1516 	if (irqchip->irq_enable) {
1517 		gc->irq.irq_enable = irqchip->irq_enable;
1518 		irqchip->irq_enable = gpiochip_irq_enable;
1519 	} else {
1520 		gc->irq.irq_unmask = irqchip->irq_unmask;
1521 		irqchip->irq_unmask = gpiochip_irq_unmask;
1522 	}
1523 }
1524 
1525 /**
1526  * gpiochip_add_irqchip() - adds an IRQ chip to a GPIO chip
1527  * @gc: the GPIO chip to add the IRQ chip to
1528  * @lock_key: lockdep class for IRQ lock
1529  * @request_key: lockdep class for IRQ request
1530  */
gpiochip_add_irqchip(struct gpio_chip * gc,struct lock_class_key * lock_key,struct lock_class_key * request_key)1531 static int gpiochip_add_irqchip(struct gpio_chip *gc,
1532 				struct lock_class_key *lock_key,
1533 				struct lock_class_key *request_key)
1534 {
1535 	struct fwnode_handle *fwnode = dev_fwnode(&gc->gpiodev->dev);
1536 	struct irq_chip *irqchip = gc->irq.chip;
1537 	unsigned int type;
1538 	unsigned int i;
1539 
1540 	if (!irqchip)
1541 		return 0;
1542 
1543 	if (gc->irq.parent_handler && gc->can_sleep) {
1544 		chip_err(gc, "you cannot have chained interrupts on a chip that may sleep\n");
1545 		return -EINVAL;
1546 	}
1547 
1548 	type = gc->irq.default_type;
1549 
1550 	/*
1551 	 * Specifying a default trigger is a terrible idea if DT or ACPI is
1552 	 * used to configure the interrupts, as you may end up with
1553 	 * conflicting triggers. Tell the user, and reset to NONE.
1554 	 */
1555 	if (WARN(fwnode && type != IRQ_TYPE_NONE,
1556 		 "%pfw: Ignoring %u default trigger\n", fwnode, type))
1557 		type = IRQ_TYPE_NONE;
1558 
1559 	if (gc->to_irq)
1560 		chip_warn(gc, "to_irq is redefined in %s and you shouldn't rely on it\n", __func__);
1561 
1562 	gc->to_irq = gpiochip_to_irq;
1563 	gc->irq.default_type = type;
1564 	gc->irq.lock_key = lock_key;
1565 	gc->irq.request_key = request_key;
1566 
1567 	/* If a parent irqdomain is provided, let's build a hierarchy */
1568 	if (gpiochip_hierarchy_is_hierarchical(gc)) {
1569 		int ret = gpiochip_hierarchy_add_domain(gc);
1570 		if (ret)
1571 			return ret;
1572 	} else {
1573 		/* Some drivers provide custom irqdomain ops */
1574 		gc->irq.domain = irq_domain_create_simple(fwnode,
1575 			gc->ngpio,
1576 			gc->irq.first,
1577 			gc->irq.domain_ops ?: &gpiochip_domain_ops,
1578 			gc);
1579 		if (!gc->irq.domain)
1580 			return -EINVAL;
1581 	}
1582 
1583 	if (gc->irq.parent_handler) {
1584 		for (i = 0; i < gc->irq.num_parents; i++) {
1585 			void *data;
1586 
1587 			if (gc->irq.per_parent_data)
1588 				data = gc->irq.parent_handler_data_array[i];
1589 			else
1590 				data = gc->irq.parent_handler_data ?: gc;
1591 
1592 			/*
1593 			 * The parent IRQ chip is already using the chip_data
1594 			 * for this IRQ chip, so our callbacks simply use the
1595 			 * handler_data.
1596 			 */
1597 			irq_set_chained_handler_and_data(gc->irq.parents[i],
1598 							 gc->irq.parent_handler,
1599 							 data);
1600 		}
1601 	}
1602 
1603 	gpiochip_set_irq_hooks(gc);
1604 
1605 	/*
1606 	 * Using barrier() here to prevent compiler from reordering
1607 	 * gc->irq.initialized before initialization of above
1608 	 * GPIO chip irq members.
1609 	 */
1610 	barrier();
1611 
1612 	gc->irq.initialized = true;
1613 
1614 	acpi_gpiochip_request_interrupts(gc);
1615 
1616 	return 0;
1617 }
1618 
1619 /**
1620  * gpiochip_irqchip_remove() - removes an irqchip added to a gpiochip
1621  * @gc: the gpiochip to remove the irqchip from
1622  *
1623  * This is called only from gpiochip_remove()
1624  */
gpiochip_irqchip_remove(struct gpio_chip * gc)1625 static void gpiochip_irqchip_remove(struct gpio_chip *gc)
1626 {
1627 	struct irq_chip *irqchip = gc->irq.chip;
1628 	unsigned int offset;
1629 
1630 	acpi_gpiochip_free_interrupts(gc);
1631 
1632 	if (irqchip && gc->irq.parent_handler) {
1633 		struct gpio_irq_chip *irq = &gc->irq;
1634 		unsigned int i;
1635 
1636 		for (i = 0; i < irq->num_parents; i++)
1637 			irq_set_chained_handler_and_data(irq->parents[i],
1638 							 NULL, NULL);
1639 	}
1640 
1641 	/* Remove all IRQ mappings and delete the domain */
1642 	if (gc->irq.domain) {
1643 		unsigned int irq;
1644 
1645 		for (offset = 0; offset < gc->ngpio; offset++) {
1646 			if (!gpiochip_irqchip_irq_valid(gc, offset))
1647 				continue;
1648 
1649 			irq = irq_find_mapping(gc->irq.domain, offset);
1650 			irq_dispose_mapping(irq);
1651 		}
1652 
1653 		irq_domain_remove(gc->irq.domain);
1654 	}
1655 
1656 	if (irqchip && !(irqchip->flags & IRQCHIP_IMMUTABLE)) {
1657 		if (irqchip->irq_request_resources == gpiochip_irq_reqres) {
1658 			irqchip->irq_request_resources = NULL;
1659 			irqchip->irq_release_resources = NULL;
1660 		}
1661 		if (irqchip->irq_enable == gpiochip_irq_enable) {
1662 			irqchip->irq_enable = gc->irq.irq_enable;
1663 			irqchip->irq_disable = gc->irq.irq_disable;
1664 		}
1665 	}
1666 	gc->irq.irq_enable = NULL;
1667 	gc->irq.irq_disable = NULL;
1668 	gc->irq.chip = NULL;
1669 
1670 	gpiochip_irqchip_free_valid_mask(gc);
1671 }
1672 
1673 /**
1674  * gpiochip_irqchip_add_domain() - adds an irqdomain to a gpiochip
1675  * @gc: the gpiochip to add the irqchip to
1676  * @domain: the irqdomain to add to the gpiochip
1677  *
1678  * This function adds an IRQ domain to the gpiochip.
1679  */
gpiochip_irqchip_add_domain(struct gpio_chip * gc,struct irq_domain * domain)1680 int gpiochip_irqchip_add_domain(struct gpio_chip *gc,
1681 				struct irq_domain *domain)
1682 {
1683 	if (!domain)
1684 		return -EINVAL;
1685 
1686 	gc->to_irq = gpiochip_to_irq;
1687 	gc->irq.domain = domain;
1688 
1689 	return 0;
1690 }
1691 EXPORT_SYMBOL_GPL(gpiochip_irqchip_add_domain);
1692 
1693 #else /* CONFIG_GPIOLIB_IRQCHIP */
1694 
gpiochip_add_irqchip(struct gpio_chip * gc,struct lock_class_key * lock_key,struct lock_class_key * request_key)1695 static inline int gpiochip_add_irqchip(struct gpio_chip *gc,
1696 				       struct lock_class_key *lock_key,
1697 				       struct lock_class_key *request_key)
1698 {
1699 	return 0;
1700 }
gpiochip_irqchip_remove(struct gpio_chip * gc)1701 static void gpiochip_irqchip_remove(struct gpio_chip *gc) {}
1702 
gpiochip_irqchip_init_hw(struct gpio_chip * gc)1703 static inline int gpiochip_irqchip_init_hw(struct gpio_chip *gc)
1704 {
1705 	return 0;
1706 }
1707 
gpiochip_irqchip_init_valid_mask(struct gpio_chip * gc)1708 static inline int gpiochip_irqchip_init_valid_mask(struct gpio_chip *gc)
1709 {
1710 	return 0;
1711 }
gpiochip_irqchip_free_valid_mask(struct gpio_chip * gc)1712 static inline void gpiochip_irqchip_free_valid_mask(struct gpio_chip *gc)
1713 { }
1714 
1715 #endif /* CONFIG_GPIOLIB_IRQCHIP */
1716 
1717 /**
1718  * gpiochip_generic_request() - request the gpio function for a pin
1719  * @gc: the gpiochip owning the GPIO
1720  * @offset: the offset of the GPIO to request for GPIO function
1721  */
gpiochip_generic_request(struct gpio_chip * gc,unsigned int offset)1722 int gpiochip_generic_request(struct gpio_chip *gc, unsigned int offset)
1723 {
1724 #ifdef CONFIG_PINCTRL
1725 	if (list_empty(&gc->gpiodev->pin_ranges))
1726 		return 0;
1727 #endif
1728 
1729 	return pinctrl_gpio_request(gc->gpiodev->base + offset);
1730 }
1731 EXPORT_SYMBOL_GPL(gpiochip_generic_request);
1732 
1733 /**
1734  * gpiochip_generic_free() - free the gpio function from a pin
1735  * @gc: the gpiochip to request the gpio function for
1736  * @offset: the offset of the GPIO to free from GPIO function
1737  */
gpiochip_generic_free(struct gpio_chip * gc,unsigned int offset)1738 void gpiochip_generic_free(struct gpio_chip *gc, unsigned int offset)
1739 {
1740 #ifdef CONFIG_PINCTRL
1741 	if (list_empty(&gc->gpiodev->pin_ranges))
1742 		return;
1743 #endif
1744 
1745 	pinctrl_gpio_free(gc->gpiodev->base + offset);
1746 }
1747 EXPORT_SYMBOL_GPL(gpiochip_generic_free);
1748 
1749 /**
1750  * gpiochip_generic_config() - apply configuration for a pin
1751  * @gc: the gpiochip owning the GPIO
1752  * @offset: the offset of the GPIO to apply the configuration
1753  * @config: the configuration to be applied
1754  */
gpiochip_generic_config(struct gpio_chip * gc,unsigned int offset,unsigned long config)1755 int gpiochip_generic_config(struct gpio_chip *gc, unsigned int offset,
1756 			    unsigned long config)
1757 {
1758 	return pinctrl_gpio_set_config(gc->gpiodev->base + offset, config);
1759 }
1760 EXPORT_SYMBOL_GPL(gpiochip_generic_config);
1761 
1762 #ifdef CONFIG_PINCTRL
1763 
1764 /**
1765  * gpiochip_add_pingroup_range() - add a range for GPIO <-> pin mapping
1766  * @gc: the gpiochip to add the range for
1767  * @pctldev: the pin controller to map to
1768  * @gpio_offset: the start offset in the current gpio_chip number space
1769  * @pin_group: name of the pin group inside the pin controller
1770  *
1771  * Calling this function directly from a DeviceTree-supported
1772  * pinctrl driver is DEPRECATED. Please see Section 2.1 of
1773  * Documentation/devicetree/bindings/gpio/gpio.txt on how to
1774  * bind pinctrl and gpio drivers via the "gpio-ranges" property.
1775  */
gpiochip_add_pingroup_range(struct gpio_chip * gc,struct pinctrl_dev * pctldev,unsigned int gpio_offset,const char * pin_group)1776 int gpiochip_add_pingroup_range(struct gpio_chip *gc,
1777 			struct pinctrl_dev *pctldev,
1778 			unsigned int gpio_offset, const char *pin_group)
1779 {
1780 	struct gpio_pin_range *pin_range;
1781 	struct gpio_device *gdev = gc->gpiodev;
1782 	int ret;
1783 
1784 	pin_range = kzalloc(sizeof(*pin_range), GFP_KERNEL);
1785 	if (!pin_range) {
1786 		chip_err(gc, "failed to allocate pin ranges\n");
1787 		return -ENOMEM;
1788 	}
1789 
1790 	/* Use local offset as range ID */
1791 	pin_range->range.id = gpio_offset;
1792 	pin_range->range.gc = gc;
1793 	pin_range->range.name = gc->label;
1794 	pin_range->range.base = gdev->base + gpio_offset;
1795 	pin_range->pctldev = pctldev;
1796 
1797 	ret = pinctrl_get_group_pins(pctldev, pin_group,
1798 					&pin_range->range.pins,
1799 					&pin_range->range.npins);
1800 	if (ret < 0) {
1801 		kfree(pin_range);
1802 		return ret;
1803 	}
1804 
1805 	pinctrl_add_gpio_range(pctldev, &pin_range->range);
1806 
1807 	chip_dbg(gc, "created GPIO range %d->%d ==> %s PINGRP %s\n",
1808 		 gpio_offset, gpio_offset + pin_range->range.npins - 1,
1809 		 pinctrl_dev_get_devname(pctldev), pin_group);
1810 
1811 	list_add_tail(&pin_range->node, &gdev->pin_ranges);
1812 
1813 	return 0;
1814 }
1815 EXPORT_SYMBOL_GPL(gpiochip_add_pingroup_range);
1816 
1817 /**
1818  * gpiochip_add_pin_range() - add a range for GPIO <-> pin mapping
1819  * @gc: the gpiochip to add the range for
1820  * @pinctl_name: the dev_name() of the pin controller to map to
1821  * @gpio_offset: the start offset in the current gpio_chip number space
1822  * @pin_offset: the start offset in the pin controller number space
1823  * @npins: the number of pins from the offset of each pin space (GPIO and
1824  *	pin controller) to accumulate in this range
1825  *
1826  * Returns:
1827  * 0 on success, or a negative error-code on failure.
1828  *
1829  * Calling this function directly from a DeviceTree-supported
1830  * pinctrl driver is DEPRECATED. Please see Section 2.1 of
1831  * Documentation/devicetree/bindings/gpio/gpio.txt on how to
1832  * bind pinctrl and gpio drivers via the "gpio-ranges" property.
1833  */
gpiochip_add_pin_range(struct gpio_chip * gc,const char * pinctl_name,unsigned int gpio_offset,unsigned int pin_offset,unsigned int npins)1834 int gpiochip_add_pin_range(struct gpio_chip *gc, const char *pinctl_name,
1835 			   unsigned int gpio_offset, unsigned int pin_offset,
1836 			   unsigned int npins)
1837 {
1838 	struct gpio_pin_range *pin_range;
1839 	struct gpio_device *gdev = gc->gpiodev;
1840 	int ret;
1841 
1842 	pin_range = kzalloc(sizeof(*pin_range), GFP_KERNEL);
1843 	if (!pin_range) {
1844 		chip_err(gc, "failed to allocate pin ranges\n");
1845 		return -ENOMEM;
1846 	}
1847 
1848 	/* Use local offset as range ID */
1849 	pin_range->range.id = gpio_offset;
1850 	pin_range->range.gc = gc;
1851 	pin_range->range.name = gc->label;
1852 	pin_range->range.base = gdev->base + gpio_offset;
1853 	pin_range->range.pin_base = pin_offset;
1854 	pin_range->range.npins = npins;
1855 	pin_range->pctldev = pinctrl_find_and_add_gpio_range(pinctl_name,
1856 			&pin_range->range);
1857 	if (IS_ERR(pin_range->pctldev)) {
1858 		ret = PTR_ERR(pin_range->pctldev);
1859 		chip_err(gc, "could not create pin range\n");
1860 		kfree(pin_range);
1861 		return ret;
1862 	}
1863 	chip_dbg(gc, "created GPIO range %d->%d ==> %s PIN %d->%d\n",
1864 		 gpio_offset, gpio_offset + npins - 1,
1865 		 pinctl_name,
1866 		 pin_offset, pin_offset + npins - 1);
1867 
1868 	list_add_tail(&pin_range->node, &gdev->pin_ranges);
1869 
1870 	return 0;
1871 }
1872 EXPORT_SYMBOL_GPL(gpiochip_add_pin_range);
1873 
1874 /**
1875  * gpiochip_remove_pin_ranges() - remove all the GPIO <-> pin mappings
1876  * @gc: the chip to remove all the mappings for
1877  */
gpiochip_remove_pin_ranges(struct gpio_chip * gc)1878 void gpiochip_remove_pin_ranges(struct gpio_chip *gc)
1879 {
1880 	struct gpio_pin_range *pin_range, *tmp;
1881 	struct gpio_device *gdev = gc->gpiodev;
1882 
1883 	list_for_each_entry_safe(pin_range, tmp, &gdev->pin_ranges, node) {
1884 		list_del(&pin_range->node);
1885 		pinctrl_remove_gpio_range(pin_range->pctldev,
1886 				&pin_range->range);
1887 		kfree(pin_range);
1888 	}
1889 }
1890 EXPORT_SYMBOL_GPL(gpiochip_remove_pin_ranges);
1891 
1892 #endif /* CONFIG_PINCTRL */
1893 
1894 /* These "optional" allocation calls help prevent drivers from stomping
1895  * on each other, and help provide better diagnostics in debugfs.
1896  * They're called even less than the "set direction" calls.
1897  */
gpiod_request_commit(struct gpio_desc * desc,const char * label)1898 static int gpiod_request_commit(struct gpio_desc *desc, const char *label)
1899 {
1900 	struct gpio_chip	*gc = desc->gdev->chip;
1901 	int			ret;
1902 	unsigned long		flags;
1903 	unsigned		offset;
1904 
1905 	if (label) {
1906 		label = kstrdup_const(label, GFP_KERNEL);
1907 		if (!label)
1908 			return -ENOMEM;
1909 	}
1910 
1911 	spin_lock_irqsave(&gpio_lock, flags);
1912 
1913 	/* NOTE:  gpio_request() can be called in early boot,
1914 	 * before IRQs are enabled, for non-sleeping (SOC) GPIOs.
1915 	 */
1916 
1917 	if (test_and_set_bit(FLAG_REQUESTED, &desc->flags) == 0) {
1918 		desc_set_label(desc, label ? : "?");
1919 	} else {
1920 		ret = -EBUSY;
1921 		goto out_free_unlock;
1922 	}
1923 
1924 	if (gc->request) {
1925 		/* gc->request may sleep */
1926 		spin_unlock_irqrestore(&gpio_lock, flags);
1927 		offset = gpio_chip_hwgpio(desc);
1928 		if (gpiochip_line_is_valid(gc, offset))
1929 			ret = gc->request(gc, offset);
1930 		else
1931 			ret = -EINVAL;
1932 		spin_lock_irqsave(&gpio_lock, flags);
1933 
1934 		if (ret) {
1935 			desc_set_label(desc, NULL);
1936 			clear_bit(FLAG_REQUESTED, &desc->flags);
1937 			goto out_free_unlock;
1938 		}
1939 	}
1940 	if (gc->get_direction) {
1941 		/* gc->get_direction may sleep */
1942 		spin_unlock_irqrestore(&gpio_lock, flags);
1943 		gpiod_get_direction(desc);
1944 		spin_lock_irqsave(&gpio_lock, flags);
1945 	}
1946 	spin_unlock_irqrestore(&gpio_lock, flags);
1947 	return 0;
1948 
1949 out_free_unlock:
1950 	spin_unlock_irqrestore(&gpio_lock, flags);
1951 	kfree_const(label);
1952 	return ret;
1953 }
1954 
1955 /*
1956  * This descriptor validation needs to be inserted verbatim into each
1957  * function taking a descriptor, so we need to use a preprocessor
1958  * macro to avoid endless duplication. If the desc is NULL it is an
1959  * optional GPIO and calls should just bail out.
1960  */
validate_desc(const struct gpio_desc * desc,const char * func)1961 static int validate_desc(const struct gpio_desc *desc, const char *func)
1962 {
1963 	if (!desc)
1964 		return 0;
1965 	if (IS_ERR(desc)) {
1966 		pr_warn("%s: invalid GPIO (errorpointer)\n", func);
1967 		return PTR_ERR(desc);
1968 	}
1969 	if (!desc->gdev) {
1970 		pr_warn("%s: invalid GPIO (no device)\n", func);
1971 		return -EINVAL;
1972 	}
1973 	if (!desc->gdev->chip) {
1974 		dev_warn(&desc->gdev->dev,
1975 			 "%s: backing chip is gone\n", func);
1976 		return 0;
1977 	}
1978 	return 1;
1979 }
1980 
1981 #define VALIDATE_DESC(desc) do { \
1982 	int __valid = validate_desc(desc, __func__); \
1983 	if (__valid <= 0) \
1984 		return __valid; \
1985 	} while (0)
1986 
1987 #define VALIDATE_DESC_VOID(desc) do { \
1988 	int __valid = validate_desc(desc, __func__); \
1989 	if (__valid <= 0) \
1990 		return; \
1991 	} while (0)
1992 
gpiod_request(struct gpio_desc * desc,const char * label)1993 int gpiod_request(struct gpio_desc *desc, const char *label)
1994 {
1995 	int ret = -EPROBE_DEFER;
1996 	struct gpio_device *gdev;
1997 
1998 	VALIDATE_DESC(desc);
1999 	gdev = desc->gdev;
2000 
2001 	if (try_module_get(gdev->owner)) {
2002 		ret = gpiod_request_commit(desc, label);
2003 		if (ret)
2004 			module_put(gdev->owner);
2005 		else
2006 			get_device(&gdev->dev);
2007 	}
2008 
2009 	if (ret)
2010 		gpiod_dbg(desc, "%s: status %d\n", __func__, ret);
2011 
2012 	return ret;
2013 }
2014 
gpiod_free_commit(struct gpio_desc * desc)2015 static bool gpiod_free_commit(struct gpio_desc *desc)
2016 {
2017 	bool			ret = false;
2018 	unsigned long		flags;
2019 	struct gpio_chip	*gc;
2020 
2021 	might_sleep();
2022 
2023 	gpiod_unexport(desc);
2024 
2025 	spin_lock_irqsave(&gpio_lock, flags);
2026 
2027 	gc = desc->gdev->chip;
2028 	if (gc && test_bit(FLAG_REQUESTED, &desc->flags)) {
2029 		if (gc->free) {
2030 			spin_unlock_irqrestore(&gpio_lock, flags);
2031 			might_sleep_if(gc->can_sleep);
2032 			gc->free(gc, gpio_chip_hwgpio(desc));
2033 			spin_lock_irqsave(&gpio_lock, flags);
2034 		}
2035 		kfree_const(desc->label);
2036 		desc_set_label(desc, NULL);
2037 		clear_bit(FLAG_ACTIVE_LOW, &desc->flags);
2038 		clear_bit(FLAG_REQUESTED, &desc->flags);
2039 		clear_bit(FLAG_OPEN_DRAIN, &desc->flags);
2040 		clear_bit(FLAG_OPEN_SOURCE, &desc->flags);
2041 		clear_bit(FLAG_PULL_UP, &desc->flags);
2042 		clear_bit(FLAG_PULL_DOWN, &desc->flags);
2043 		clear_bit(FLAG_BIAS_DISABLE, &desc->flags);
2044 		clear_bit(FLAG_EDGE_RISING, &desc->flags);
2045 		clear_bit(FLAG_EDGE_FALLING, &desc->flags);
2046 		clear_bit(FLAG_IS_HOGGED, &desc->flags);
2047 #ifdef CONFIG_OF_DYNAMIC
2048 		desc->hog = NULL;
2049 #endif
2050 #ifdef CONFIG_GPIO_CDEV
2051 		WRITE_ONCE(desc->debounce_period_us, 0);
2052 #endif
2053 		ret = true;
2054 	}
2055 
2056 	spin_unlock_irqrestore(&gpio_lock, flags);
2057 	blocking_notifier_call_chain(&desc->gdev->notifier,
2058 				     GPIOLINE_CHANGED_RELEASED, desc);
2059 
2060 	return ret;
2061 }
2062 
gpiod_free(struct gpio_desc * desc)2063 void gpiod_free(struct gpio_desc *desc)
2064 {
2065 	if (desc && desc->gdev && gpiod_free_commit(desc)) {
2066 		module_put(desc->gdev->owner);
2067 		put_device(&desc->gdev->dev);
2068 	} else {
2069 		WARN_ON(extra_checks);
2070 	}
2071 }
2072 
2073 /**
2074  * gpiochip_is_requested - return string iff signal was requested
2075  * @gc: controller managing the signal
2076  * @offset: of signal within controller's 0..(ngpio - 1) range
2077  *
2078  * Returns NULL if the GPIO is not currently requested, else a string.
2079  * The string returned is the label passed to gpio_request(); if none has been
2080  * passed it is a meaningless, non-NULL constant.
2081  *
2082  * This function is for use by GPIO controller drivers.  The label can
2083  * help with diagnostics, and knowing that the signal is used as a GPIO
2084  * can help avoid accidentally multiplexing it to another controller.
2085  */
gpiochip_is_requested(struct gpio_chip * gc,unsigned int offset)2086 const char *gpiochip_is_requested(struct gpio_chip *gc, unsigned int offset)
2087 {
2088 	struct gpio_desc *desc;
2089 
2090 	desc = gpiochip_get_desc(gc, offset);
2091 	if (IS_ERR(desc))
2092 		return NULL;
2093 
2094 	if (test_bit(FLAG_REQUESTED, &desc->flags) == 0)
2095 		return NULL;
2096 	return desc->label;
2097 }
2098 EXPORT_SYMBOL_GPL(gpiochip_is_requested);
2099 
2100 /**
2101  * gpiochip_request_own_desc - Allow GPIO chip to request its own descriptor
2102  * @gc: GPIO chip
2103  * @hwnum: hardware number of the GPIO for which to request the descriptor
2104  * @label: label for the GPIO
2105  * @lflags: lookup flags for this GPIO or 0 if default, this can be used to
2106  * specify things like line inversion semantics with the machine flags
2107  * such as GPIO_OUT_LOW
2108  * @dflags: descriptor request flags for this GPIO or 0 if default, this
2109  * can be used to specify consumer semantics such as open drain
2110  *
2111  * Function allows GPIO chip drivers to request and use their own GPIO
2112  * descriptors via gpiolib API. Difference to gpiod_request() is that this
2113  * function will not increase reference count of the GPIO chip module. This
2114  * allows the GPIO chip module to be unloaded as needed (we assume that the
2115  * GPIO chip driver handles freeing the GPIOs it has requested).
2116  *
2117  * Returns:
2118  * A pointer to the GPIO descriptor, or an ERR_PTR()-encoded negative error
2119  * code on failure.
2120  */
gpiochip_request_own_desc(struct gpio_chip * gc,unsigned int hwnum,const char * label,enum gpio_lookup_flags lflags,enum gpiod_flags dflags)2121 struct gpio_desc *gpiochip_request_own_desc(struct gpio_chip *gc,
2122 					    unsigned int hwnum,
2123 					    const char *label,
2124 					    enum gpio_lookup_flags lflags,
2125 					    enum gpiod_flags dflags)
2126 {
2127 	struct gpio_desc *desc = gpiochip_get_desc(gc, hwnum);
2128 	int ret;
2129 
2130 	if (IS_ERR(desc)) {
2131 		chip_err(gc, "failed to get GPIO descriptor\n");
2132 		return desc;
2133 	}
2134 
2135 	ret = gpiod_request_commit(desc, label);
2136 	if (ret < 0)
2137 		return ERR_PTR(ret);
2138 
2139 	ret = gpiod_configure_flags(desc, label, lflags, dflags);
2140 	if (ret) {
2141 		chip_err(gc, "setup of own GPIO %s failed\n", label);
2142 		gpiod_free_commit(desc);
2143 		return ERR_PTR(ret);
2144 	}
2145 
2146 	return desc;
2147 }
2148 EXPORT_SYMBOL_GPL(gpiochip_request_own_desc);
2149 
2150 /**
2151  * gpiochip_free_own_desc - Free GPIO requested by the chip driver
2152  * @desc: GPIO descriptor to free
2153  *
2154  * Function frees the given GPIO requested previously with
2155  * gpiochip_request_own_desc().
2156  */
gpiochip_free_own_desc(struct gpio_desc * desc)2157 void gpiochip_free_own_desc(struct gpio_desc *desc)
2158 {
2159 	if (desc)
2160 		gpiod_free_commit(desc);
2161 }
2162 EXPORT_SYMBOL_GPL(gpiochip_free_own_desc);
2163 
2164 /*
2165  * Drivers MUST set GPIO direction before making get/set calls.  In
2166  * some cases this is done in early boot, before IRQs are enabled.
2167  *
2168  * As a rule these aren't called more than once (except for drivers
2169  * using the open-drain emulation idiom) so these are natural places
2170  * to accumulate extra debugging checks.  Note that we can't (yet)
2171  * rely on gpio_request() having been called beforehand.
2172  */
2173 
gpio_do_set_config(struct gpio_chip * gc,unsigned int offset,unsigned long config)2174 static int gpio_do_set_config(struct gpio_chip *gc, unsigned int offset,
2175 			      unsigned long config)
2176 {
2177 	if (!gc->set_config)
2178 		return -ENOTSUPP;
2179 
2180 	return gc->set_config(gc, offset, config);
2181 }
2182 
gpio_set_config_with_argument(struct gpio_desc * desc,enum pin_config_param mode,u32 argument)2183 static int gpio_set_config_with_argument(struct gpio_desc *desc,
2184 					 enum pin_config_param mode,
2185 					 u32 argument)
2186 {
2187 	struct gpio_chip *gc = desc->gdev->chip;
2188 	unsigned long config;
2189 
2190 	config = pinconf_to_config_packed(mode, argument);
2191 	return gpio_do_set_config(gc, gpio_chip_hwgpio(desc), config);
2192 }
2193 
gpio_set_config_with_argument_optional(struct gpio_desc * desc,enum pin_config_param mode,u32 argument)2194 static int gpio_set_config_with_argument_optional(struct gpio_desc *desc,
2195 						  enum pin_config_param mode,
2196 						  u32 argument)
2197 {
2198 	struct device *dev = &desc->gdev->dev;
2199 	int gpio = gpio_chip_hwgpio(desc);
2200 	int ret;
2201 
2202 	ret = gpio_set_config_with_argument(desc, mode, argument);
2203 	if (ret != -ENOTSUPP)
2204 		return ret;
2205 
2206 	switch (mode) {
2207 	case PIN_CONFIG_PERSIST_STATE:
2208 		dev_dbg(dev, "Persistence not supported for GPIO %d\n", gpio);
2209 		break;
2210 	default:
2211 		break;
2212 	}
2213 
2214 	return 0;
2215 }
2216 
gpio_set_config(struct gpio_desc * desc,enum pin_config_param mode)2217 static int gpio_set_config(struct gpio_desc *desc, enum pin_config_param mode)
2218 {
2219 	return gpio_set_config_with_argument(desc, mode, 0);
2220 }
2221 
gpio_set_bias(struct gpio_desc * desc)2222 static int gpio_set_bias(struct gpio_desc *desc)
2223 {
2224 	enum pin_config_param bias;
2225 	unsigned int arg;
2226 
2227 	if (test_bit(FLAG_BIAS_DISABLE, &desc->flags))
2228 		bias = PIN_CONFIG_BIAS_DISABLE;
2229 	else if (test_bit(FLAG_PULL_UP, &desc->flags))
2230 		bias = PIN_CONFIG_BIAS_PULL_UP;
2231 	else if (test_bit(FLAG_PULL_DOWN, &desc->flags))
2232 		bias = PIN_CONFIG_BIAS_PULL_DOWN;
2233 	else
2234 		return 0;
2235 
2236 	switch (bias) {
2237 	case PIN_CONFIG_BIAS_PULL_DOWN:
2238 	case PIN_CONFIG_BIAS_PULL_UP:
2239 		arg = 1;
2240 		break;
2241 
2242 	default:
2243 		arg = 0;
2244 		break;
2245 	}
2246 
2247 	return gpio_set_config_with_argument_optional(desc, bias, arg);
2248 }
2249 
2250 /**
2251  * gpio_set_debounce_timeout() - Set debounce timeout
2252  * @desc:	GPIO descriptor to set the debounce timeout
2253  * @debounce:	Debounce timeout in microseconds
2254  *
2255  * The function calls the certain GPIO driver to set debounce timeout
2256  * in the hardware.
2257  *
2258  * Returns 0 on success, or negative error code otherwise.
2259  */
gpio_set_debounce_timeout(struct gpio_desc * desc,unsigned int debounce)2260 int gpio_set_debounce_timeout(struct gpio_desc *desc, unsigned int debounce)
2261 {
2262 	return gpio_set_config_with_argument_optional(desc,
2263 						      PIN_CONFIG_INPUT_DEBOUNCE,
2264 						      debounce);
2265 }
2266 
2267 /**
2268  * gpiod_direction_input - set the GPIO direction to input
2269  * @desc:	GPIO to set to input
2270  *
2271  * Set the direction of the passed GPIO to input, such as gpiod_get_value() can
2272  * be called safely on it.
2273  *
2274  * Return 0 in case of success, else an error code.
2275  */
gpiod_direction_input(struct gpio_desc * desc)2276 int gpiod_direction_input(struct gpio_desc *desc)
2277 {
2278 	struct gpio_chip	*gc;
2279 	int			ret = 0;
2280 
2281 	VALIDATE_DESC(desc);
2282 	gc = desc->gdev->chip;
2283 
2284 	/*
2285 	 * It is legal to have no .get() and .direction_input() specified if
2286 	 * the chip is output-only, but you can't specify .direction_input()
2287 	 * and not support the .get() operation, that doesn't make sense.
2288 	 */
2289 	if (!gc->get && gc->direction_input) {
2290 		gpiod_warn(desc,
2291 			   "%s: missing get() but have direction_input()\n",
2292 			   __func__);
2293 		return -EIO;
2294 	}
2295 
2296 	/*
2297 	 * If we have a .direction_input() callback, things are simple,
2298 	 * just call it. Else we are some input-only chip so try to check the
2299 	 * direction (if .get_direction() is supported) else we silently
2300 	 * assume we are in input mode after this.
2301 	 */
2302 	if (gc->direction_input) {
2303 		ret = gc->direction_input(gc, gpio_chip_hwgpio(desc));
2304 	} else if (gc->get_direction &&
2305 		  (gc->get_direction(gc, gpio_chip_hwgpio(desc)) != 1)) {
2306 		gpiod_warn(desc,
2307 			   "%s: missing direction_input() operation and line is output\n",
2308 			   __func__);
2309 		return -EIO;
2310 	}
2311 	if (ret == 0) {
2312 		clear_bit(FLAG_IS_OUT, &desc->flags);
2313 		ret = gpio_set_bias(desc);
2314 	}
2315 
2316 	trace_gpio_direction(desc_to_gpio(desc), 1, ret);
2317 
2318 	return ret;
2319 }
2320 EXPORT_SYMBOL_GPL(gpiod_direction_input);
2321 
gpiod_direction_output_raw_commit(struct gpio_desc * desc,int value)2322 static int gpiod_direction_output_raw_commit(struct gpio_desc *desc, int value)
2323 {
2324 	struct gpio_chip *gc = desc->gdev->chip;
2325 	int val = !!value;
2326 	int ret = 0;
2327 
2328 	/*
2329 	 * It's OK not to specify .direction_output() if the gpiochip is
2330 	 * output-only, but if there is then not even a .set() operation it
2331 	 * is pretty tricky to drive the output line.
2332 	 */
2333 	if (!gc->set && !gc->direction_output) {
2334 		gpiod_warn(desc,
2335 			   "%s: missing set() and direction_output() operations\n",
2336 			   __func__);
2337 		return -EIO;
2338 	}
2339 
2340 	if (gc->direction_output) {
2341 		ret = gc->direction_output(gc, gpio_chip_hwgpio(desc), val);
2342 	} else {
2343 		/* Check that we are in output mode if we can */
2344 		if (gc->get_direction &&
2345 		    gc->get_direction(gc, gpio_chip_hwgpio(desc))) {
2346 			gpiod_warn(desc,
2347 				"%s: missing direction_output() operation\n",
2348 				__func__);
2349 			return -EIO;
2350 		}
2351 		/*
2352 		 * If we can't actively set the direction, we are some
2353 		 * output-only chip, so just drive the output as desired.
2354 		 */
2355 		gc->set(gc, gpio_chip_hwgpio(desc), val);
2356 	}
2357 
2358 	if (!ret)
2359 		set_bit(FLAG_IS_OUT, &desc->flags);
2360 	trace_gpio_value(desc_to_gpio(desc), 0, val);
2361 	trace_gpio_direction(desc_to_gpio(desc), 0, ret);
2362 	return ret;
2363 }
2364 
2365 /**
2366  * gpiod_direction_output_raw - set the GPIO direction to output
2367  * @desc:	GPIO to set to output
2368  * @value:	initial output value of the GPIO
2369  *
2370  * Set the direction of the passed GPIO to output, such as gpiod_set_value() can
2371  * be called safely on it. The initial value of the output must be specified
2372  * as raw value on the physical line without regard for the ACTIVE_LOW status.
2373  *
2374  * Return 0 in case of success, else an error code.
2375  */
gpiod_direction_output_raw(struct gpio_desc * desc,int value)2376 int gpiod_direction_output_raw(struct gpio_desc *desc, int value)
2377 {
2378 	VALIDATE_DESC(desc);
2379 	return gpiod_direction_output_raw_commit(desc, value);
2380 }
2381 EXPORT_SYMBOL_GPL(gpiod_direction_output_raw);
2382 
2383 /**
2384  * gpiod_direction_output - set the GPIO direction to output
2385  * @desc:	GPIO to set to output
2386  * @value:	initial output value of the GPIO
2387  *
2388  * Set the direction of the passed GPIO to output, such as gpiod_set_value() can
2389  * be called safely on it. The initial value of the output must be specified
2390  * as the logical value of the GPIO, i.e. taking its ACTIVE_LOW status into
2391  * account.
2392  *
2393  * Return 0 in case of success, else an error code.
2394  */
gpiod_direction_output(struct gpio_desc * desc,int value)2395 int gpiod_direction_output(struct gpio_desc *desc, int value)
2396 {
2397 	int ret;
2398 
2399 	VALIDATE_DESC(desc);
2400 	if (test_bit(FLAG_ACTIVE_LOW, &desc->flags))
2401 		value = !value;
2402 	else
2403 		value = !!value;
2404 
2405 	/* GPIOs used for enabled IRQs shall not be set as output */
2406 	if (test_bit(FLAG_USED_AS_IRQ, &desc->flags) &&
2407 	    test_bit(FLAG_IRQ_IS_ENABLED, &desc->flags)) {
2408 		gpiod_err(desc,
2409 			  "%s: tried to set a GPIO tied to an IRQ as output\n",
2410 			  __func__);
2411 		return -EIO;
2412 	}
2413 
2414 	if (test_bit(FLAG_OPEN_DRAIN, &desc->flags)) {
2415 		/* First see if we can enable open drain in hardware */
2416 		ret = gpio_set_config(desc, PIN_CONFIG_DRIVE_OPEN_DRAIN);
2417 		if (!ret)
2418 			goto set_output_value;
2419 		/* Emulate open drain by not actively driving the line high */
2420 		if (value) {
2421 			ret = gpiod_direction_input(desc);
2422 			goto set_output_flag;
2423 		}
2424 	} else if (test_bit(FLAG_OPEN_SOURCE, &desc->flags)) {
2425 		ret = gpio_set_config(desc, PIN_CONFIG_DRIVE_OPEN_SOURCE);
2426 		if (!ret)
2427 			goto set_output_value;
2428 		/* Emulate open source by not actively driving the line low */
2429 		if (!value) {
2430 			ret = gpiod_direction_input(desc);
2431 			goto set_output_flag;
2432 		}
2433 	} else {
2434 		gpio_set_config(desc, PIN_CONFIG_DRIVE_PUSH_PULL);
2435 	}
2436 
2437 set_output_value:
2438 	ret = gpio_set_bias(desc);
2439 	if (ret)
2440 		return ret;
2441 	return gpiod_direction_output_raw_commit(desc, value);
2442 
2443 set_output_flag:
2444 	/*
2445 	 * When emulating open-source or open-drain functionalities by not
2446 	 * actively driving the line (setting mode to input) we still need to
2447 	 * set the IS_OUT flag or otherwise we won't be able to set the line
2448 	 * value anymore.
2449 	 */
2450 	if (ret == 0)
2451 		set_bit(FLAG_IS_OUT, &desc->flags);
2452 	return ret;
2453 }
2454 EXPORT_SYMBOL_GPL(gpiod_direction_output);
2455 
2456 /**
2457  * gpiod_enable_hw_timestamp_ns - Enable hardware timestamp in nanoseconds.
2458  *
2459  * @desc: GPIO to enable.
2460  * @flags: Flags related to GPIO edge.
2461  *
2462  * Return 0 in case of success, else negative error code.
2463  */
gpiod_enable_hw_timestamp_ns(struct gpio_desc * desc,unsigned long flags)2464 int gpiod_enable_hw_timestamp_ns(struct gpio_desc *desc, unsigned long flags)
2465 {
2466 	int ret = 0;
2467 	struct gpio_chip *gc;
2468 
2469 	VALIDATE_DESC(desc);
2470 
2471 	gc = desc->gdev->chip;
2472 	if (!gc->en_hw_timestamp) {
2473 		gpiod_warn(desc, "%s: hw ts not supported\n", __func__);
2474 		return -ENOTSUPP;
2475 	}
2476 
2477 	ret = gc->en_hw_timestamp(gc, gpio_chip_hwgpio(desc), flags);
2478 	if (ret)
2479 		gpiod_warn(desc, "%s: hw ts request failed\n", __func__);
2480 
2481 	return ret;
2482 }
2483 EXPORT_SYMBOL_GPL(gpiod_enable_hw_timestamp_ns);
2484 
2485 /**
2486  * gpiod_disable_hw_timestamp_ns - Disable hardware timestamp.
2487  *
2488  * @desc: GPIO to disable.
2489  * @flags: Flags related to GPIO edge, same value as used during enable call.
2490  *
2491  * Return 0 in case of success, else negative error code.
2492  */
gpiod_disable_hw_timestamp_ns(struct gpio_desc * desc,unsigned long flags)2493 int gpiod_disable_hw_timestamp_ns(struct gpio_desc *desc, unsigned long flags)
2494 {
2495 	int ret = 0;
2496 	struct gpio_chip *gc;
2497 
2498 	VALIDATE_DESC(desc);
2499 
2500 	gc = desc->gdev->chip;
2501 	if (!gc->dis_hw_timestamp) {
2502 		gpiod_warn(desc, "%s: hw ts not supported\n", __func__);
2503 		return -ENOTSUPP;
2504 	}
2505 
2506 	ret = gc->dis_hw_timestamp(gc, gpio_chip_hwgpio(desc), flags);
2507 	if (ret)
2508 		gpiod_warn(desc, "%s: hw ts release failed\n", __func__);
2509 
2510 	return ret;
2511 }
2512 EXPORT_SYMBOL_GPL(gpiod_disable_hw_timestamp_ns);
2513 
2514 /**
2515  * gpiod_set_config - sets @config for a GPIO
2516  * @desc: descriptor of the GPIO for which to set the configuration
2517  * @config: Same packed config format as generic pinconf
2518  *
2519  * Returns:
2520  * 0 on success, %-ENOTSUPP if the controller doesn't support setting the
2521  * configuration.
2522  */
gpiod_set_config(struct gpio_desc * desc,unsigned long config)2523 int gpiod_set_config(struct gpio_desc *desc, unsigned long config)
2524 {
2525 	struct gpio_chip *gc;
2526 
2527 	VALIDATE_DESC(desc);
2528 	gc = desc->gdev->chip;
2529 
2530 	return gpio_do_set_config(gc, gpio_chip_hwgpio(desc), config);
2531 }
2532 EXPORT_SYMBOL_GPL(gpiod_set_config);
2533 
2534 /**
2535  * gpiod_set_debounce - sets @debounce time for a GPIO
2536  * @desc: descriptor of the GPIO for which to set debounce time
2537  * @debounce: debounce time in microseconds
2538  *
2539  * Returns:
2540  * 0 on success, %-ENOTSUPP if the controller doesn't support setting the
2541  * debounce time.
2542  */
gpiod_set_debounce(struct gpio_desc * desc,unsigned int debounce)2543 int gpiod_set_debounce(struct gpio_desc *desc, unsigned int debounce)
2544 {
2545 	unsigned long config;
2546 
2547 	config = pinconf_to_config_packed(PIN_CONFIG_INPUT_DEBOUNCE, debounce);
2548 	return gpiod_set_config(desc, config);
2549 }
2550 EXPORT_SYMBOL_GPL(gpiod_set_debounce);
2551 
2552 /**
2553  * gpiod_set_transitory - Lose or retain GPIO state on suspend or reset
2554  * @desc: descriptor of the GPIO for which to configure persistence
2555  * @transitory: True to lose state on suspend or reset, false for persistence
2556  *
2557  * Returns:
2558  * 0 on success, otherwise a negative error code.
2559  */
gpiod_set_transitory(struct gpio_desc * desc,bool transitory)2560 int gpiod_set_transitory(struct gpio_desc *desc, bool transitory)
2561 {
2562 	VALIDATE_DESC(desc);
2563 	/*
2564 	 * Handle FLAG_TRANSITORY first, enabling queries to gpiolib for
2565 	 * persistence state.
2566 	 */
2567 	assign_bit(FLAG_TRANSITORY, &desc->flags, transitory);
2568 
2569 	/* If the driver supports it, set the persistence state now */
2570 	return gpio_set_config_with_argument_optional(desc,
2571 						      PIN_CONFIG_PERSIST_STATE,
2572 						      !transitory);
2573 }
2574 EXPORT_SYMBOL_GPL(gpiod_set_transitory);
2575 
2576 /**
2577  * gpiod_is_active_low - test whether a GPIO is active-low or not
2578  * @desc: the gpio descriptor to test
2579  *
2580  * Returns 1 if the GPIO is active-low, 0 otherwise.
2581  */
gpiod_is_active_low(const struct gpio_desc * desc)2582 int gpiod_is_active_low(const struct gpio_desc *desc)
2583 {
2584 	VALIDATE_DESC(desc);
2585 	return test_bit(FLAG_ACTIVE_LOW, &desc->flags);
2586 }
2587 EXPORT_SYMBOL_GPL(gpiod_is_active_low);
2588 
2589 /**
2590  * gpiod_toggle_active_low - toggle whether a GPIO is active-low or not
2591  * @desc: the gpio descriptor to change
2592  */
gpiod_toggle_active_low(struct gpio_desc * desc)2593 void gpiod_toggle_active_low(struct gpio_desc *desc)
2594 {
2595 	VALIDATE_DESC_VOID(desc);
2596 	change_bit(FLAG_ACTIVE_LOW, &desc->flags);
2597 }
2598 EXPORT_SYMBOL_GPL(gpiod_toggle_active_low);
2599 
gpio_chip_get_value(struct gpio_chip * gc,const struct gpio_desc * desc)2600 static int gpio_chip_get_value(struct gpio_chip *gc, const struct gpio_desc *desc)
2601 {
2602 	return gc->get ? gc->get(gc, gpio_chip_hwgpio(desc)) : -EIO;
2603 }
2604 
2605 /* I/O calls are only valid after configuration completed; the relevant
2606  * "is this a valid GPIO" error checks should already have been done.
2607  *
2608  * "Get" operations are often inlinable as reading a pin value register,
2609  * and masking the relevant bit in that register.
2610  *
2611  * When "set" operations are inlinable, they involve writing that mask to
2612  * one register to set a low value, or a different register to set it high.
2613  * Otherwise locking is needed, so there may be little value to inlining.
2614  *
2615  *------------------------------------------------------------------------
2616  *
2617  * IMPORTANT!!!  The hot paths -- get/set value -- assume that callers
2618  * have requested the GPIO.  That can include implicit requesting by
2619  * a direction setting call.  Marking a gpio as requested locks its chip
2620  * in memory, guaranteeing that these table lookups need no more locking
2621  * and that gpiochip_remove() will fail.
2622  *
2623  * REVISIT when debugging, consider adding some instrumentation to ensure
2624  * that the GPIO was actually requested.
2625  */
2626 
gpiod_get_raw_value_commit(const struct gpio_desc * desc)2627 static int gpiod_get_raw_value_commit(const struct gpio_desc *desc)
2628 {
2629 	struct gpio_chip	*gc;
2630 	int value;
2631 
2632 	gc = desc->gdev->chip;
2633 	value = gpio_chip_get_value(gc, desc);
2634 	value = value < 0 ? value : !!value;
2635 	trace_gpio_value(desc_to_gpio(desc), 1, value);
2636 	return value;
2637 }
2638 
gpio_chip_get_multiple(struct gpio_chip * gc,unsigned long * mask,unsigned long * bits)2639 static int gpio_chip_get_multiple(struct gpio_chip *gc,
2640 				  unsigned long *mask, unsigned long *bits)
2641 {
2642 	if (gc->get_multiple)
2643 		return gc->get_multiple(gc, mask, bits);
2644 	if (gc->get) {
2645 		int i, value;
2646 
2647 		for_each_set_bit(i, mask, gc->ngpio) {
2648 			value = gc->get(gc, i);
2649 			if (value < 0)
2650 				return value;
2651 			__assign_bit(i, bits, value);
2652 		}
2653 		return 0;
2654 	}
2655 	return -EIO;
2656 }
2657 
gpiod_get_array_value_complex(bool raw,bool can_sleep,unsigned int array_size,struct gpio_desc ** desc_array,struct gpio_array * array_info,unsigned long * value_bitmap)2658 int gpiod_get_array_value_complex(bool raw, bool can_sleep,
2659 				  unsigned int array_size,
2660 				  struct gpio_desc **desc_array,
2661 				  struct gpio_array *array_info,
2662 				  unsigned long *value_bitmap)
2663 {
2664 	int ret, i = 0;
2665 
2666 	/*
2667 	 * Validate array_info against desc_array and its size.
2668 	 * It should immediately follow desc_array if both
2669 	 * have been obtained from the same gpiod_get_array() call.
2670 	 */
2671 	if (array_info && array_info->desc == desc_array &&
2672 	    array_size <= array_info->size &&
2673 	    (void *)array_info == desc_array + array_info->size) {
2674 		if (!can_sleep)
2675 			WARN_ON(array_info->chip->can_sleep);
2676 
2677 		ret = gpio_chip_get_multiple(array_info->chip,
2678 					     array_info->get_mask,
2679 					     value_bitmap);
2680 		if (ret)
2681 			return ret;
2682 
2683 		if (!raw && !bitmap_empty(array_info->invert_mask, array_size))
2684 			bitmap_xor(value_bitmap, value_bitmap,
2685 				   array_info->invert_mask, array_size);
2686 
2687 		i = find_first_zero_bit(array_info->get_mask, array_size);
2688 		if (i == array_size)
2689 			return 0;
2690 	} else {
2691 		array_info = NULL;
2692 	}
2693 
2694 	while (i < array_size) {
2695 		struct gpio_chip *gc = desc_array[i]->gdev->chip;
2696 		DECLARE_BITMAP(fastpath_mask, FASTPATH_NGPIO);
2697 		DECLARE_BITMAP(fastpath_bits, FASTPATH_NGPIO);
2698 		unsigned long *mask, *bits;
2699 		int first, j;
2700 
2701 		if (likely(gc->ngpio <= FASTPATH_NGPIO)) {
2702 			mask = fastpath_mask;
2703 			bits = fastpath_bits;
2704 		} else {
2705 			gfp_t flags = can_sleep ? GFP_KERNEL : GFP_ATOMIC;
2706 
2707 			mask = bitmap_alloc(gc->ngpio, flags);
2708 			if (!mask)
2709 				return -ENOMEM;
2710 
2711 			bits = bitmap_alloc(gc->ngpio, flags);
2712 			if (!bits) {
2713 				bitmap_free(mask);
2714 				return -ENOMEM;
2715 			}
2716 		}
2717 
2718 		bitmap_zero(mask, gc->ngpio);
2719 
2720 		if (!can_sleep)
2721 			WARN_ON(gc->can_sleep);
2722 
2723 		/* collect all inputs belonging to the same chip */
2724 		first = i;
2725 		do {
2726 			const struct gpio_desc *desc = desc_array[i];
2727 			int hwgpio = gpio_chip_hwgpio(desc);
2728 
2729 			__set_bit(hwgpio, mask);
2730 			i++;
2731 
2732 			if (array_info)
2733 				i = find_next_zero_bit(array_info->get_mask,
2734 						       array_size, i);
2735 		} while ((i < array_size) &&
2736 			 (desc_array[i]->gdev->chip == gc));
2737 
2738 		ret = gpio_chip_get_multiple(gc, mask, bits);
2739 		if (ret) {
2740 			if (mask != fastpath_mask)
2741 				bitmap_free(mask);
2742 			if (bits != fastpath_bits)
2743 				bitmap_free(bits);
2744 			return ret;
2745 		}
2746 
2747 		for (j = first; j < i; ) {
2748 			const struct gpio_desc *desc = desc_array[j];
2749 			int hwgpio = gpio_chip_hwgpio(desc);
2750 			int value = test_bit(hwgpio, bits);
2751 
2752 			if (!raw && test_bit(FLAG_ACTIVE_LOW, &desc->flags))
2753 				value = !value;
2754 			__assign_bit(j, value_bitmap, value);
2755 			trace_gpio_value(desc_to_gpio(desc), 1, value);
2756 			j++;
2757 
2758 			if (array_info)
2759 				j = find_next_zero_bit(array_info->get_mask, i,
2760 						       j);
2761 		}
2762 
2763 		if (mask != fastpath_mask)
2764 			bitmap_free(mask);
2765 		if (bits != fastpath_bits)
2766 			bitmap_free(bits);
2767 	}
2768 	return 0;
2769 }
2770 
2771 /**
2772  * gpiod_get_raw_value() - return a gpio's raw value
2773  * @desc: gpio whose value will be returned
2774  *
2775  * Return the GPIO's raw value, i.e. the value of the physical line disregarding
2776  * its ACTIVE_LOW status, or negative errno on failure.
2777  *
2778  * This function can be called from contexts where we cannot sleep, and will
2779  * complain if the GPIO chip functions potentially sleep.
2780  */
gpiod_get_raw_value(const struct gpio_desc * desc)2781 int gpiod_get_raw_value(const struct gpio_desc *desc)
2782 {
2783 	VALIDATE_DESC(desc);
2784 	/* Should be using gpiod_get_raw_value_cansleep() */
2785 	WARN_ON(desc->gdev->chip->can_sleep);
2786 	return gpiod_get_raw_value_commit(desc);
2787 }
2788 EXPORT_SYMBOL_GPL(gpiod_get_raw_value);
2789 
2790 /**
2791  * gpiod_get_value() - return a gpio's value
2792  * @desc: gpio whose value will be returned
2793  *
2794  * Return the GPIO's logical value, i.e. taking the ACTIVE_LOW status into
2795  * account, or negative errno on failure.
2796  *
2797  * This function can be called from contexts where we cannot sleep, and will
2798  * complain if the GPIO chip functions potentially sleep.
2799  */
gpiod_get_value(const struct gpio_desc * desc)2800 int gpiod_get_value(const struct gpio_desc *desc)
2801 {
2802 	int value;
2803 
2804 	VALIDATE_DESC(desc);
2805 	/* Should be using gpiod_get_value_cansleep() */
2806 	WARN_ON(desc->gdev->chip->can_sleep);
2807 
2808 	value = gpiod_get_raw_value_commit(desc);
2809 	if (value < 0)
2810 		return value;
2811 
2812 	if (test_bit(FLAG_ACTIVE_LOW, &desc->flags))
2813 		value = !value;
2814 
2815 	return value;
2816 }
2817 EXPORT_SYMBOL_GPL(gpiod_get_value);
2818 
2819 /**
2820  * gpiod_get_raw_array_value() - read raw values from an array of GPIOs
2821  * @array_size: number of elements in the descriptor array / value bitmap
2822  * @desc_array: array of GPIO descriptors whose values will be read
2823  * @array_info: information on applicability of fast bitmap processing path
2824  * @value_bitmap: bitmap to store the read values
2825  *
2826  * Read the raw values of the GPIOs, i.e. the values of the physical lines
2827  * without regard for their ACTIVE_LOW status.  Return 0 in case of success,
2828  * else an error code.
2829  *
2830  * This function can be called from contexts where we cannot sleep,
2831  * and it will complain if the GPIO chip functions potentially sleep.
2832  */
gpiod_get_raw_array_value(unsigned int array_size,struct gpio_desc ** desc_array,struct gpio_array * array_info,unsigned long * value_bitmap)2833 int gpiod_get_raw_array_value(unsigned int array_size,
2834 			      struct gpio_desc **desc_array,
2835 			      struct gpio_array *array_info,
2836 			      unsigned long *value_bitmap)
2837 {
2838 	if (!desc_array)
2839 		return -EINVAL;
2840 	return gpiod_get_array_value_complex(true, false, array_size,
2841 					     desc_array, array_info,
2842 					     value_bitmap);
2843 }
2844 EXPORT_SYMBOL_GPL(gpiod_get_raw_array_value);
2845 
2846 /**
2847  * gpiod_get_array_value() - read values from an array of GPIOs
2848  * @array_size: number of elements in the descriptor array / value bitmap
2849  * @desc_array: array of GPIO descriptors whose values will be read
2850  * @array_info: information on applicability of fast bitmap processing path
2851  * @value_bitmap: bitmap to store the read values
2852  *
2853  * Read the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status
2854  * into account.  Return 0 in case of success, else an error code.
2855  *
2856  * This function can be called from contexts where we cannot sleep,
2857  * and it will complain if the GPIO chip functions potentially sleep.
2858  */
gpiod_get_array_value(unsigned int array_size,struct gpio_desc ** desc_array,struct gpio_array * array_info,unsigned long * value_bitmap)2859 int gpiod_get_array_value(unsigned int array_size,
2860 			  struct gpio_desc **desc_array,
2861 			  struct gpio_array *array_info,
2862 			  unsigned long *value_bitmap)
2863 {
2864 	if (!desc_array)
2865 		return -EINVAL;
2866 	return gpiod_get_array_value_complex(false, false, array_size,
2867 					     desc_array, array_info,
2868 					     value_bitmap);
2869 }
2870 EXPORT_SYMBOL_GPL(gpiod_get_array_value);
2871 
2872 /*
2873  *  gpio_set_open_drain_value_commit() - Set the open drain gpio's value.
2874  * @desc: gpio descriptor whose state need to be set.
2875  * @value: Non-zero for setting it HIGH otherwise it will set to LOW.
2876  */
gpio_set_open_drain_value_commit(struct gpio_desc * desc,bool value)2877 static void gpio_set_open_drain_value_commit(struct gpio_desc *desc, bool value)
2878 {
2879 	int ret = 0;
2880 	struct gpio_chip *gc = desc->gdev->chip;
2881 	int offset = gpio_chip_hwgpio(desc);
2882 
2883 	if (value) {
2884 		ret = gc->direction_input(gc, offset);
2885 	} else {
2886 		ret = gc->direction_output(gc, offset, 0);
2887 		if (!ret)
2888 			set_bit(FLAG_IS_OUT, &desc->flags);
2889 	}
2890 	trace_gpio_direction(desc_to_gpio(desc), value, ret);
2891 	if (ret < 0)
2892 		gpiod_err(desc,
2893 			  "%s: Error in set_value for open drain err %d\n",
2894 			  __func__, ret);
2895 }
2896 
2897 /*
2898  *  _gpio_set_open_source_value() - Set the open source gpio's value.
2899  * @desc: gpio descriptor whose state need to be set.
2900  * @value: Non-zero for setting it HIGH otherwise it will set to LOW.
2901  */
gpio_set_open_source_value_commit(struct gpio_desc * desc,bool value)2902 static void gpio_set_open_source_value_commit(struct gpio_desc *desc, bool value)
2903 {
2904 	int ret = 0;
2905 	struct gpio_chip *gc = desc->gdev->chip;
2906 	int offset = gpio_chip_hwgpio(desc);
2907 
2908 	if (value) {
2909 		ret = gc->direction_output(gc, offset, 1);
2910 		if (!ret)
2911 			set_bit(FLAG_IS_OUT, &desc->flags);
2912 	} else {
2913 		ret = gc->direction_input(gc, offset);
2914 	}
2915 	trace_gpio_direction(desc_to_gpio(desc), !value, ret);
2916 	if (ret < 0)
2917 		gpiod_err(desc,
2918 			  "%s: Error in set_value for open source err %d\n",
2919 			  __func__, ret);
2920 }
2921 
gpiod_set_raw_value_commit(struct gpio_desc * desc,bool value)2922 static void gpiod_set_raw_value_commit(struct gpio_desc *desc, bool value)
2923 {
2924 	struct gpio_chip	*gc;
2925 
2926 	gc = desc->gdev->chip;
2927 	trace_gpio_value(desc_to_gpio(desc), 0, value);
2928 	gc->set(gc, gpio_chip_hwgpio(desc), value);
2929 }
2930 
2931 /*
2932  * set multiple outputs on the same chip;
2933  * use the chip's set_multiple function if available;
2934  * otherwise set the outputs sequentially;
2935  * @chip: the GPIO chip we operate on
2936  * @mask: bit mask array; one bit per output; BITS_PER_LONG bits per word
2937  *        defines which outputs are to be changed
2938  * @bits: bit value array; one bit per output; BITS_PER_LONG bits per word
2939  *        defines the values the outputs specified by mask are to be set to
2940  */
gpio_chip_set_multiple(struct gpio_chip * gc,unsigned long * mask,unsigned long * bits)2941 static void gpio_chip_set_multiple(struct gpio_chip *gc,
2942 				   unsigned long *mask, unsigned long *bits)
2943 {
2944 	if (gc->set_multiple) {
2945 		gc->set_multiple(gc, mask, bits);
2946 	} else {
2947 		unsigned int i;
2948 
2949 		/* set outputs if the corresponding mask bit is set */
2950 		for_each_set_bit(i, mask, gc->ngpio)
2951 			gc->set(gc, i, test_bit(i, bits));
2952 	}
2953 }
2954 
gpiod_set_array_value_complex(bool raw,bool can_sleep,unsigned int array_size,struct gpio_desc ** desc_array,struct gpio_array * array_info,unsigned long * value_bitmap)2955 int gpiod_set_array_value_complex(bool raw, bool can_sleep,
2956 				  unsigned int array_size,
2957 				  struct gpio_desc **desc_array,
2958 				  struct gpio_array *array_info,
2959 				  unsigned long *value_bitmap)
2960 {
2961 	int i = 0;
2962 
2963 	/*
2964 	 * Validate array_info against desc_array and its size.
2965 	 * It should immediately follow desc_array if both
2966 	 * have been obtained from the same gpiod_get_array() call.
2967 	 */
2968 	if (array_info && array_info->desc == desc_array &&
2969 	    array_size <= array_info->size &&
2970 	    (void *)array_info == desc_array + array_info->size) {
2971 		if (!can_sleep)
2972 			WARN_ON(array_info->chip->can_sleep);
2973 
2974 		if (!raw && !bitmap_empty(array_info->invert_mask, array_size))
2975 			bitmap_xor(value_bitmap, value_bitmap,
2976 				   array_info->invert_mask, array_size);
2977 
2978 		gpio_chip_set_multiple(array_info->chip, array_info->set_mask,
2979 				       value_bitmap);
2980 
2981 		i = find_first_zero_bit(array_info->set_mask, array_size);
2982 		if (i == array_size)
2983 			return 0;
2984 	} else {
2985 		array_info = NULL;
2986 	}
2987 
2988 	while (i < array_size) {
2989 		struct gpio_chip *gc = desc_array[i]->gdev->chip;
2990 		DECLARE_BITMAP(fastpath_mask, FASTPATH_NGPIO);
2991 		DECLARE_BITMAP(fastpath_bits, FASTPATH_NGPIO);
2992 		unsigned long *mask, *bits;
2993 		int count = 0;
2994 
2995 		if (likely(gc->ngpio <= FASTPATH_NGPIO)) {
2996 			mask = fastpath_mask;
2997 			bits = fastpath_bits;
2998 		} else {
2999 			gfp_t flags = can_sleep ? GFP_KERNEL : GFP_ATOMIC;
3000 
3001 			mask = bitmap_alloc(gc->ngpio, flags);
3002 			if (!mask)
3003 				return -ENOMEM;
3004 
3005 			bits = bitmap_alloc(gc->ngpio, flags);
3006 			if (!bits) {
3007 				bitmap_free(mask);
3008 				return -ENOMEM;
3009 			}
3010 		}
3011 
3012 		bitmap_zero(mask, gc->ngpio);
3013 
3014 		if (!can_sleep)
3015 			WARN_ON(gc->can_sleep);
3016 
3017 		do {
3018 			struct gpio_desc *desc = desc_array[i];
3019 			int hwgpio = gpio_chip_hwgpio(desc);
3020 			int value = test_bit(i, value_bitmap);
3021 
3022 			/*
3023 			 * Pins applicable for fast input but not for
3024 			 * fast output processing may have been already
3025 			 * inverted inside the fast path, skip them.
3026 			 */
3027 			if (!raw && !(array_info &&
3028 			    test_bit(i, array_info->invert_mask)) &&
3029 			    test_bit(FLAG_ACTIVE_LOW, &desc->flags))
3030 				value = !value;
3031 			trace_gpio_value(desc_to_gpio(desc), 0, value);
3032 			/*
3033 			 * collect all normal outputs belonging to the same chip
3034 			 * open drain and open source outputs are set individually
3035 			 */
3036 			if (test_bit(FLAG_OPEN_DRAIN, &desc->flags) && !raw) {
3037 				gpio_set_open_drain_value_commit(desc, value);
3038 			} else if (test_bit(FLAG_OPEN_SOURCE, &desc->flags) && !raw) {
3039 				gpio_set_open_source_value_commit(desc, value);
3040 			} else {
3041 				__set_bit(hwgpio, mask);
3042 				__assign_bit(hwgpio, bits, value);
3043 				count++;
3044 			}
3045 			i++;
3046 
3047 			if (array_info)
3048 				i = find_next_zero_bit(array_info->set_mask,
3049 						       array_size, i);
3050 		} while ((i < array_size) &&
3051 			 (desc_array[i]->gdev->chip == gc));
3052 		/* push collected bits to outputs */
3053 		if (count != 0)
3054 			gpio_chip_set_multiple(gc, mask, bits);
3055 
3056 		if (mask != fastpath_mask)
3057 			bitmap_free(mask);
3058 		if (bits != fastpath_bits)
3059 			bitmap_free(bits);
3060 	}
3061 	return 0;
3062 }
3063 
3064 /**
3065  * gpiod_set_raw_value() - assign a gpio's raw value
3066  * @desc: gpio whose value will be assigned
3067  * @value: value to assign
3068  *
3069  * Set the raw value of the GPIO, i.e. the value of its physical line without
3070  * regard for its ACTIVE_LOW status.
3071  *
3072  * This function can be called from contexts where we cannot sleep, and will
3073  * complain if the GPIO chip functions potentially sleep.
3074  */
gpiod_set_raw_value(struct gpio_desc * desc,int value)3075 void gpiod_set_raw_value(struct gpio_desc *desc, int value)
3076 {
3077 	VALIDATE_DESC_VOID(desc);
3078 	/* Should be using gpiod_set_raw_value_cansleep() */
3079 	WARN_ON(desc->gdev->chip->can_sleep);
3080 	gpiod_set_raw_value_commit(desc, value);
3081 }
3082 EXPORT_SYMBOL_GPL(gpiod_set_raw_value);
3083 
3084 /**
3085  * gpiod_set_value_nocheck() - set a GPIO line value without checking
3086  * @desc: the descriptor to set the value on
3087  * @value: value to set
3088  *
3089  * This sets the value of a GPIO line backing a descriptor, applying
3090  * different semantic quirks like active low and open drain/source
3091  * handling.
3092  */
gpiod_set_value_nocheck(struct gpio_desc * desc,int value)3093 static void gpiod_set_value_nocheck(struct gpio_desc *desc, int value)
3094 {
3095 	if (test_bit(FLAG_ACTIVE_LOW, &desc->flags))
3096 		value = !value;
3097 	if (test_bit(FLAG_OPEN_DRAIN, &desc->flags))
3098 		gpio_set_open_drain_value_commit(desc, value);
3099 	else if (test_bit(FLAG_OPEN_SOURCE, &desc->flags))
3100 		gpio_set_open_source_value_commit(desc, value);
3101 	else
3102 		gpiod_set_raw_value_commit(desc, value);
3103 }
3104 
3105 /**
3106  * gpiod_set_value() - assign a gpio's value
3107  * @desc: gpio whose value will be assigned
3108  * @value: value to assign
3109  *
3110  * Set the logical value of the GPIO, i.e. taking its ACTIVE_LOW,
3111  * OPEN_DRAIN and OPEN_SOURCE flags into account.
3112  *
3113  * This function can be called from contexts where we cannot sleep, and will
3114  * complain if the GPIO chip functions potentially sleep.
3115  */
gpiod_set_value(struct gpio_desc * desc,int value)3116 void gpiod_set_value(struct gpio_desc *desc, int value)
3117 {
3118 	VALIDATE_DESC_VOID(desc);
3119 	/* Should be using gpiod_set_value_cansleep() */
3120 	WARN_ON(desc->gdev->chip->can_sleep);
3121 	gpiod_set_value_nocheck(desc, value);
3122 }
3123 EXPORT_SYMBOL_GPL(gpiod_set_value);
3124 
3125 /**
3126  * gpiod_set_raw_array_value() - assign values to an array of GPIOs
3127  * @array_size: number of elements in the descriptor array / value bitmap
3128  * @desc_array: array of GPIO descriptors whose values will be assigned
3129  * @array_info: information on applicability of fast bitmap processing path
3130  * @value_bitmap: bitmap of values to assign
3131  *
3132  * Set the raw values of the GPIOs, i.e. the values of the physical lines
3133  * without regard for their ACTIVE_LOW status.
3134  *
3135  * This function can be called from contexts where we cannot sleep, and will
3136  * complain if the GPIO chip functions potentially sleep.
3137  */
gpiod_set_raw_array_value(unsigned int array_size,struct gpio_desc ** desc_array,struct gpio_array * array_info,unsigned long * value_bitmap)3138 int gpiod_set_raw_array_value(unsigned int array_size,
3139 			      struct gpio_desc **desc_array,
3140 			      struct gpio_array *array_info,
3141 			      unsigned long *value_bitmap)
3142 {
3143 	if (!desc_array)
3144 		return -EINVAL;
3145 	return gpiod_set_array_value_complex(true, false, array_size,
3146 					desc_array, array_info, value_bitmap);
3147 }
3148 EXPORT_SYMBOL_GPL(gpiod_set_raw_array_value);
3149 
3150 /**
3151  * gpiod_set_array_value() - assign values to an array of GPIOs
3152  * @array_size: number of elements in the descriptor array / value bitmap
3153  * @desc_array: array of GPIO descriptors whose values will be assigned
3154  * @array_info: information on applicability of fast bitmap processing path
3155  * @value_bitmap: bitmap of values to assign
3156  *
3157  * Set the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status
3158  * into account.
3159  *
3160  * This function can be called from contexts where we cannot sleep, and will
3161  * complain if the GPIO chip functions potentially sleep.
3162  */
gpiod_set_array_value(unsigned int array_size,struct gpio_desc ** desc_array,struct gpio_array * array_info,unsigned long * value_bitmap)3163 int gpiod_set_array_value(unsigned int array_size,
3164 			  struct gpio_desc **desc_array,
3165 			  struct gpio_array *array_info,
3166 			  unsigned long *value_bitmap)
3167 {
3168 	if (!desc_array)
3169 		return -EINVAL;
3170 	return gpiod_set_array_value_complex(false, false, array_size,
3171 					     desc_array, array_info,
3172 					     value_bitmap);
3173 }
3174 EXPORT_SYMBOL_GPL(gpiod_set_array_value);
3175 
3176 /**
3177  * gpiod_cansleep() - report whether gpio value access may sleep
3178  * @desc: gpio to check
3179  *
3180  */
gpiod_cansleep(const struct gpio_desc * desc)3181 int gpiod_cansleep(const struct gpio_desc *desc)
3182 {
3183 	VALIDATE_DESC(desc);
3184 	return desc->gdev->chip->can_sleep;
3185 }
3186 EXPORT_SYMBOL_GPL(gpiod_cansleep);
3187 
3188 /**
3189  * gpiod_set_consumer_name() - set the consumer name for the descriptor
3190  * @desc: gpio to set the consumer name on
3191  * @name: the new consumer name
3192  */
gpiod_set_consumer_name(struct gpio_desc * desc,const char * name)3193 int gpiod_set_consumer_name(struct gpio_desc *desc, const char *name)
3194 {
3195 	VALIDATE_DESC(desc);
3196 	if (name) {
3197 		name = kstrdup_const(name, GFP_KERNEL);
3198 		if (!name)
3199 			return -ENOMEM;
3200 	}
3201 
3202 	kfree_const(desc->label);
3203 	desc_set_label(desc, name);
3204 
3205 	return 0;
3206 }
3207 EXPORT_SYMBOL_GPL(gpiod_set_consumer_name);
3208 
3209 /**
3210  * gpiod_to_irq() - return the IRQ corresponding to a GPIO
3211  * @desc: gpio whose IRQ will be returned (already requested)
3212  *
3213  * Return the IRQ corresponding to the passed GPIO, or an error code in case of
3214  * error.
3215  */
gpiod_to_irq(const struct gpio_desc * desc)3216 int gpiod_to_irq(const struct gpio_desc *desc)
3217 {
3218 	struct gpio_chip *gc;
3219 	int offset;
3220 
3221 	/*
3222 	 * Cannot VALIDATE_DESC() here as gpiod_to_irq() consumer semantics
3223 	 * requires this function to not return zero on an invalid descriptor
3224 	 * but rather a negative error number.
3225 	 */
3226 	if (!desc || IS_ERR(desc) || !desc->gdev || !desc->gdev->chip)
3227 		return -EINVAL;
3228 
3229 	gc = desc->gdev->chip;
3230 	offset = gpio_chip_hwgpio(desc);
3231 	if (gc->to_irq) {
3232 		int retirq = gc->to_irq(gc, offset);
3233 
3234 		/* Zero means NO_IRQ */
3235 		if (!retirq)
3236 			return -ENXIO;
3237 
3238 		return retirq;
3239 	}
3240 #ifdef CONFIG_GPIOLIB_IRQCHIP
3241 	if (gc->irq.chip) {
3242 		/*
3243 		 * Avoid race condition with other code, which tries to lookup
3244 		 * an IRQ before the irqchip has been properly registered,
3245 		 * i.e. while gpiochip is still being brought up.
3246 		 */
3247 		return -EPROBE_DEFER;
3248 	}
3249 #endif
3250 	return -ENXIO;
3251 }
3252 EXPORT_SYMBOL_GPL(gpiod_to_irq);
3253 
3254 /**
3255  * gpiochip_lock_as_irq() - lock a GPIO to be used as IRQ
3256  * @gc: the chip the GPIO to lock belongs to
3257  * @offset: the offset of the GPIO to lock as IRQ
3258  *
3259  * This is used directly by GPIO drivers that want to lock down
3260  * a certain GPIO line to be used for IRQs.
3261  */
gpiochip_lock_as_irq(struct gpio_chip * gc,unsigned int offset)3262 int gpiochip_lock_as_irq(struct gpio_chip *gc, unsigned int offset)
3263 {
3264 	struct gpio_desc *desc;
3265 
3266 	desc = gpiochip_get_desc(gc, offset);
3267 	if (IS_ERR(desc))
3268 		return PTR_ERR(desc);
3269 
3270 	/*
3271 	 * If it's fast: flush the direction setting if something changed
3272 	 * behind our back
3273 	 */
3274 	if (!gc->can_sleep && gc->get_direction) {
3275 		int dir = gpiod_get_direction(desc);
3276 
3277 		if (dir < 0) {
3278 			chip_err(gc, "%s: cannot get GPIO direction\n",
3279 				 __func__);
3280 			return dir;
3281 		}
3282 	}
3283 
3284 	/* To be valid for IRQ the line needs to be input or open drain */
3285 	if (test_bit(FLAG_IS_OUT, &desc->flags) &&
3286 	    !test_bit(FLAG_OPEN_DRAIN, &desc->flags)) {
3287 		chip_err(gc,
3288 			 "%s: tried to flag a GPIO set as output for IRQ\n",
3289 			 __func__);
3290 		return -EIO;
3291 	}
3292 
3293 	set_bit(FLAG_USED_AS_IRQ, &desc->flags);
3294 	set_bit(FLAG_IRQ_IS_ENABLED, &desc->flags);
3295 
3296 	/*
3297 	 * If the consumer has not set up a label (such as when the
3298 	 * IRQ is referenced from .to_irq()) we set up a label here
3299 	 * so it is clear this is used as an interrupt.
3300 	 */
3301 	if (!desc->label)
3302 		desc_set_label(desc, "interrupt");
3303 
3304 	return 0;
3305 }
3306 EXPORT_SYMBOL_GPL(gpiochip_lock_as_irq);
3307 
3308 /**
3309  * gpiochip_unlock_as_irq() - unlock a GPIO used as IRQ
3310  * @gc: the chip the GPIO to lock belongs to
3311  * @offset: the offset of the GPIO to lock as IRQ
3312  *
3313  * This is used directly by GPIO drivers that want to indicate
3314  * that a certain GPIO is no longer used exclusively for IRQ.
3315  */
gpiochip_unlock_as_irq(struct gpio_chip * gc,unsigned int offset)3316 void gpiochip_unlock_as_irq(struct gpio_chip *gc, unsigned int offset)
3317 {
3318 	struct gpio_desc *desc;
3319 
3320 	desc = gpiochip_get_desc(gc, offset);
3321 	if (IS_ERR(desc))
3322 		return;
3323 
3324 	clear_bit(FLAG_USED_AS_IRQ, &desc->flags);
3325 	clear_bit(FLAG_IRQ_IS_ENABLED, &desc->flags);
3326 
3327 	/* If we only had this marking, erase it */
3328 	if (desc->label && !strcmp(desc->label, "interrupt"))
3329 		desc_set_label(desc, NULL);
3330 }
3331 EXPORT_SYMBOL_GPL(gpiochip_unlock_as_irq);
3332 
gpiochip_disable_irq(struct gpio_chip * gc,unsigned int offset)3333 void gpiochip_disable_irq(struct gpio_chip *gc, unsigned int offset)
3334 {
3335 	struct gpio_desc *desc = gpiochip_get_desc(gc, offset);
3336 
3337 	if (!IS_ERR(desc) &&
3338 	    !WARN_ON(!test_bit(FLAG_USED_AS_IRQ, &desc->flags)))
3339 		clear_bit(FLAG_IRQ_IS_ENABLED, &desc->flags);
3340 }
3341 EXPORT_SYMBOL_GPL(gpiochip_disable_irq);
3342 
gpiochip_enable_irq(struct gpio_chip * gc,unsigned int offset)3343 void gpiochip_enable_irq(struct gpio_chip *gc, unsigned int offset)
3344 {
3345 	struct gpio_desc *desc = gpiochip_get_desc(gc, offset);
3346 
3347 	if (!IS_ERR(desc) &&
3348 	    !WARN_ON(!test_bit(FLAG_USED_AS_IRQ, &desc->flags))) {
3349 		/*
3350 		 * We must not be output when using IRQ UNLESS we are
3351 		 * open drain.
3352 		 */
3353 		WARN_ON(test_bit(FLAG_IS_OUT, &desc->flags) &&
3354 			!test_bit(FLAG_OPEN_DRAIN, &desc->flags));
3355 		set_bit(FLAG_IRQ_IS_ENABLED, &desc->flags);
3356 	}
3357 }
3358 EXPORT_SYMBOL_GPL(gpiochip_enable_irq);
3359 
gpiochip_line_is_irq(struct gpio_chip * gc,unsigned int offset)3360 bool gpiochip_line_is_irq(struct gpio_chip *gc, unsigned int offset)
3361 {
3362 	if (offset >= gc->ngpio)
3363 		return false;
3364 
3365 	return test_bit(FLAG_USED_AS_IRQ, &gc->gpiodev->descs[offset].flags);
3366 }
3367 EXPORT_SYMBOL_GPL(gpiochip_line_is_irq);
3368 
gpiochip_reqres_irq(struct gpio_chip * gc,unsigned int offset)3369 int gpiochip_reqres_irq(struct gpio_chip *gc, unsigned int offset)
3370 {
3371 	int ret;
3372 
3373 	if (!try_module_get(gc->gpiodev->owner))
3374 		return -ENODEV;
3375 
3376 	ret = gpiochip_lock_as_irq(gc, offset);
3377 	if (ret) {
3378 		chip_err(gc, "unable to lock HW IRQ %u for IRQ\n", offset);
3379 		module_put(gc->gpiodev->owner);
3380 		return ret;
3381 	}
3382 	return 0;
3383 }
3384 EXPORT_SYMBOL_GPL(gpiochip_reqres_irq);
3385 
gpiochip_relres_irq(struct gpio_chip * gc,unsigned int offset)3386 void gpiochip_relres_irq(struct gpio_chip *gc, unsigned int offset)
3387 {
3388 	gpiochip_unlock_as_irq(gc, offset);
3389 	module_put(gc->gpiodev->owner);
3390 }
3391 EXPORT_SYMBOL_GPL(gpiochip_relres_irq);
3392 
gpiochip_line_is_open_drain(struct gpio_chip * gc,unsigned int offset)3393 bool gpiochip_line_is_open_drain(struct gpio_chip *gc, unsigned int offset)
3394 {
3395 	if (offset >= gc->ngpio)
3396 		return false;
3397 
3398 	return test_bit(FLAG_OPEN_DRAIN, &gc->gpiodev->descs[offset].flags);
3399 }
3400 EXPORT_SYMBOL_GPL(gpiochip_line_is_open_drain);
3401 
gpiochip_line_is_open_source(struct gpio_chip * gc,unsigned int offset)3402 bool gpiochip_line_is_open_source(struct gpio_chip *gc, unsigned int offset)
3403 {
3404 	if (offset >= gc->ngpio)
3405 		return false;
3406 
3407 	return test_bit(FLAG_OPEN_SOURCE, &gc->gpiodev->descs[offset].flags);
3408 }
3409 EXPORT_SYMBOL_GPL(gpiochip_line_is_open_source);
3410 
gpiochip_line_is_persistent(struct gpio_chip * gc,unsigned int offset)3411 bool gpiochip_line_is_persistent(struct gpio_chip *gc, unsigned int offset)
3412 {
3413 	if (offset >= gc->ngpio)
3414 		return false;
3415 
3416 	return !test_bit(FLAG_TRANSITORY, &gc->gpiodev->descs[offset].flags);
3417 }
3418 EXPORT_SYMBOL_GPL(gpiochip_line_is_persistent);
3419 
3420 /**
3421  * gpiod_get_raw_value_cansleep() - return a gpio's raw value
3422  * @desc: gpio whose value will be returned
3423  *
3424  * Return the GPIO's raw value, i.e. the value of the physical line disregarding
3425  * its ACTIVE_LOW status, or negative errno on failure.
3426  *
3427  * This function is to be called from contexts that can sleep.
3428  */
gpiod_get_raw_value_cansleep(const struct gpio_desc * desc)3429 int gpiod_get_raw_value_cansleep(const struct gpio_desc *desc)
3430 {
3431 	might_sleep_if(extra_checks);
3432 	VALIDATE_DESC(desc);
3433 	return gpiod_get_raw_value_commit(desc);
3434 }
3435 EXPORT_SYMBOL_GPL(gpiod_get_raw_value_cansleep);
3436 
3437 /**
3438  * gpiod_get_value_cansleep() - return a gpio's value
3439  * @desc: gpio whose value will be returned
3440  *
3441  * Return the GPIO's logical value, i.e. taking the ACTIVE_LOW status into
3442  * account, or negative errno on failure.
3443  *
3444  * This function is to be called from contexts that can sleep.
3445  */
gpiod_get_value_cansleep(const struct gpio_desc * desc)3446 int gpiod_get_value_cansleep(const struct gpio_desc *desc)
3447 {
3448 	int value;
3449 
3450 	might_sleep_if(extra_checks);
3451 	VALIDATE_DESC(desc);
3452 	value = gpiod_get_raw_value_commit(desc);
3453 	if (value < 0)
3454 		return value;
3455 
3456 	if (test_bit(FLAG_ACTIVE_LOW, &desc->flags))
3457 		value = !value;
3458 
3459 	return value;
3460 }
3461 EXPORT_SYMBOL_GPL(gpiod_get_value_cansleep);
3462 
3463 /**
3464  * gpiod_get_raw_array_value_cansleep() - read raw values from an array of GPIOs
3465  * @array_size: number of elements in the descriptor array / value bitmap
3466  * @desc_array: array of GPIO descriptors whose values will be read
3467  * @array_info: information on applicability of fast bitmap processing path
3468  * @value_bitmap: bitmap to store the read values
3469  *
3470  * Read the raw values of the GPIOs, i.e. the values of the physical lines
3471  * without regard for their ACTIVE_LOW status.  Return 0 in case of success,
3472  * else an error code.
3473  *
3474  * This function is to be called from contexts that can sleep.
3475  */
gpiod_get_raw_array_value_cansleep(unsigned int array_size,struct gpio_desc ** desc_array,struct gpio_array * array_info,unsigned long * value_bitmap)3476 int gpiod_get_raw_array_value_cansleep(unsigned int array_size,
3477 				       struct gpio_desc **desc_array,
3478 				       struct gpio_array *array_info,
3479 				       unsigned long *value_bitmap)
3480 {
3481 	might_sleep_if(extra_checks);
3482 	if (!desc_array)
3483 		return -EINVAL;
3484 	return gpiod_get_array_value_complex(true, true, array_size,
3485 					     desc_array, array_info,
3486 					     value_bitmap);
3487 }
3488 EXPORT_SYMBOL_GPL(gpiod_get_raw_array_value_cansleep);
3489 
3490 /**
3491  * gpiod_get_array_value_cansleep() - read values from an array of GPIOs
3492  * @array_size: number of elements in the descriptor array / value bitmap
3493  * @desc_array: array of GPIO descriptors whose values will be read
3494  * @array_info: information on applicability of fast bitmap processing path
3495  * @value_bitmap: bitmap to store the read values
3496  *
3497  * Read the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status
3498  * into account.  Return 0 in case of success, else an error code.
3499  *
3500  * This function is to be called from contexts that can sleep.
3501  */
gpiod_get_array_value_cansleep(unsigned int array_size,struct gpio_desc ** desc_array,struct gpio_array * array_info,unsigned long * value_bitmap)3502 int gpiod_get_array_value_cansleep(unsigned int array_size,
3503 				   struct gpio_desc **desc_array,
3504 				   struct gpio_array *array_info,
3505 				   unsigned long *value_bitmap)
3506 {
3507 	might_sleep_if(extra_checks);
3508 	if (!desc_array)
3509 		return -EINVAL;
3510 	return gpiod_get_array_value_complex(false, true, array_size,
3511 					     desc_array, array_info,
3512 					     value_bitmap);
3513 }
3514 EXPORT_SYMBOL_GPL(gpiod_get_array_value_cansleep);
3515 
3516 /**
3517  * gpiod_set_raw_value_cansleep() - assign a gpio's raw value
3518  * @desc: gpio whose value will be assigned
3519  * @value: value to assign
3520  *
3521  * Set the raw value of the GPIO, i.e. the value of its physical line without
3522  * regard for its ACTIVE_LOW status.
3523  *
3524  * This function is to be called from contexts that can sleep.
3525  */
gpiod_set_raw_value_cansleep(struct gpio_desc * desc,int value)3526 void gpiod_set_raw_value_cansleep(struct gpio_desc *desc, int value)
3527 {
3528 	might_sleep_if(extra_checks);
3529 	VALIDATE_DESC_VOID(desc);
3530 	gpiod_set_raw_value_commit(desc, value);
3531 }
3532 EXPORT_SYMBOL_GPL(gpiod_set_raw_value_cansleep);
3533 
3534 /**
3535  * gpiod_set_value_cansleep() - assign a gpio's value
3536  * @desc: gpio whose value will be assigned
3537  * @value: value to assign
3538  *
3539  * Set the logical value of the GPIO, i.e. taking its ACTIVE_LOW status into
3540  * account
3541  *
3542  * This function is to be called from contexts that can sleep.
3543  */
gpiod_set_value_cansleep(struct gpio_desc * desc,int value)3544 void gpiod_set_value_cansleep(struct gpio_desc *desc, int value)
3545 {
3546 	might_sleep_if(extra_checks);
3547 	VALIDATE_DESC_VOID(desc);
3548 	gpiod_set_value_nocheck(desc, value);
3549 }
3550 EXPORT_SYMBOL_GPL(gpiod_set_value_cansleep);
3551 
3552 /**
3553  * gpiod_set_raw_array_value_cansleep() - assign values to an array of GPIOs
3554  * @array_size: number of elements in the descriptor array / value bitmap
3555  * @desc_array: array of GPIO descriptors whose values will be assigned
3556  * @array_info: information on applicability of fast bitmap processing path
3557  * @value_bitmap: bitmap of values to assign
3558  *
3559  * Set the raw values of the GPIOs, i.e. the values of the physical lines
3560  * without regard for their ACTIVE_LOW status.
3561  *
3562  * This function is to be called from contexts that can sleep.
3563  */
gpiod_set_raw_array_value_cansleep(unsigned int array_size,struct gpio_desc ** desc_array,struct gpio_array * array_info,unsigned long * value_bitmap)3564 int gpiod_set_raw_array_value_cansleep(unsigned int array_size,
3565 				       struct gpio_desc **desc_array,
3566 				       struct gpio_array *array_info,
3567 				       unsigned long *value_bitmap)
3568 {
3569 	might_sleep_if(extra_checks);
3570 	if (!desc_array)
3571 		return -EINVAL;
3572 	return gpiod_set_array_value_complex(true, true, array_size, desc_array,
3573 				      array_info, value_bitmap);
3574 }
3575 EXPORT_SYMBOL_GPL(gpiod_set_raw_array_value_cansleep);
3576 
3577 /**
3578  * gpiod_add_lookup_tables() - register GPIO device consumers
3579  * @tables: list of tables of consumers to register
3580  * @n: number of tables in the list
3581  */
gpiod_add_lookup_tables(struct gpiod_lookup_table ** tables,size_t n)3582 void gpiod_add_lookup_tables(struct gpiod_lookup_table **tables, size_t n)
3583 {
3584 	unsigned int i;
3585 
3586 	mutex_lock(&gpio_lookup_lock);
3587 
3588 	for (i = 0; i < n; i++)
3589 		list_add_tail(&tables[i]->list, &gpio_lookup_list);
3590 
3591 	mutex_unlock(&gpio_lookup_lock);
3592 }
3593 
3594 /**
3595  * gpiod_set_array_value_cansleep() - assign values to an array of GPIOs
3596  * @array_size: number of elements in the descriptor array / value bitmap
3597  * @desc_array: array of GPIO descriptors whose values will be assigned
3598  * @array_info: information on applicability of fast bitmap processing path
3599  * @value_bitmap: bitmap of values to assign
3600  *
3601  * Set the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status
3602  * into account.
3603  *
3604  * This function is to be called from contexts that can sleep.
3605  */
gpiod_set_array_value_cansleep(unsigned int array_size,struct gpio_desc ** desc_array,struct gpio_array * array_info,unsigned long * value_bitmap)3606 int gpiod_set_array_value_cansleep(unsigned int array_size,
3607 				   struct gpio_desc **desc_array,
3608 				   struct gpio_array *array_info,
3609 				   unsigned long *value_bitmap)
3610 {
3611 	might_sleep_if(extra_checks);
3612 	if (!desc_array)
3613 		return -EINVAL;
3614 	return gpiod_set_array_value_complex(false, true, array_size,
3615 					     desc_array, array_info,
3616 					     value_bitmap);
3617 }
3618 EXPORT_SYMBOL_GPL(gpiod_set_array_value_cansleep);
3619 
3620 /**
3621  * gpiod_add_lookup_table() - register GPIO device consumers
3622  * @table: table of consumers to register
3623  */
gpiod_add_lookup_table(struct gpiod_lookup_table * table)3624 void gpiod_add_lookup_table(struct gpiod_lookup_table *table)
3625 {
3626 	gpiod_add_lookup_tables(&table, 1);
3627 }
3628 EXPORT_SYMBOL_GPL(gpiod_add_lookup_table);
3629 
3630 /**
3631  * gpiod_remove_lookup_table() - unregister GPIO device consumers
3632  * @table: table of consumers to unregister
3633  */
gpiod_remove_lookup_table(struct gpiod_lookup_table * table)3634 void gpiod_remove_lookup_table(struct gpiod_lookup_table *table)
3635 {
3636 	/* Nothing to remove */
3637 	if (!table)
3638 		return;
3639 
3640 	mutex_lock(&gpio_lookup_lock);
3641 
3642 	list_del(&table->list);
3643 
3644 	mutex_unlock(&gpio_lookup_lock);
3645 }
3646 EXPORT_SYMBOL_GPL(gpiod_remove_lookup_table);
3647 
3648 /**
3649  * gpiod_add_hogs() - register a set of GPIO hogs from machine code
3650  * @hogs: table of gpio hog entries with a zeroed sentinel at the end
3651  */
gpiod_add_hogs(struct gpiod_hog * hogs)3652 void gpiod_add_hogs(struct gpiod_hog *hogs)
3653 {
3654 	struct gpio_chip *gc;
3655 	struct gpiod_hog *hog;
3656 
3657 	mutex_lock(&gpio_machine_hogs_mutex);
3658 
3659 	for (hog = &hogs[0]; hog->chip_label; hog++) {
3660 		list_add_tail(&hog->list, &gpio_machine_hogs);
3661 
3662 		/*
3663 		 * The chip may have been registered earlier, so check if it
3664 		 * exists and, if so, try to hog the line now.
3665 		 */
3666 		gc = find_chip_by_name(hog->chip_label);
3667 		if (gc)
3668 			gpiochip_machine_hog(gc, hog);
3669 	}
3670 
3671 	mutex_unlock(&gpio_machine_hogs_mutex);
3672 }
3673 EXPORT_SYMBOL_GPL(gpiod_add_hogs);
3674 
gpiod_remove_hogs(struct gpiod_hog * hogs)3675 void gpiod_remove_hogs(struct gpiod_hog *hogs)
3676 {
3677 	struct gpiod_hog *hog;
3678 
3679 	mutex_lock(&gpio_machine_hogs_mutex);
3680 	for (hog = &hogs[0]; hog->chip_label; hog++)
3681 		list_del(&hog->list);
3682 	mutex_unlock(&gpio_machine_hogs_mutex);
3683 }
3684 EXPORT_SYMBOL_GPL(gpiod_remove_hogs);
3685 
gpiod_find_lookup_table(struct device * dev)3686 static struct gpiod_lookup_table *gpiod_find_lookup_table(struct device *dev)
3687 {
3688 	const char *dev_id = dev ? dev_name(dev) : NULL;
3689 	struct gpiod_lookup_table *table;
3690 
3691 	mutex_lock(&gpio_lookup_lock);
3692 
3693 	list_for_each_entry(table, &gpio_lookup_list, list) {
3694 		if (table->dev_id && dev_id) {
3695 			/*
3696 			 * Valid strings on both ends, must be identical to have
3697 			 * a match
3698 			 */
3699 			if (!strcmp(table->dev_id, dev_id))
3700 				goto found;
3701 		} else {
3702 			/*
3703 			 * One of the pointers is NULL, so both must be to have
3704 			 * a match
3705 			 */
3706 			if (dev_id == table->dev_id)
3707 				goto found;
3708 		}
3709 	}
3710 	table = NULL;
3711 
3712 found:
3713 	mutex_unlock(&gpio_lookup_lock);
3714 	return table;
3715 }
3716 
gpiod_find(struct device * dev,const char * con_id,unsigned int idx,unsigned long * flags)3717 static struct gpio_desc *gpiod_find(struct device *dev, const char *con_id,
3718 				    unsigned int idx, unsigned long *flags)
3719 {
3720 	struct gpio_desc *desc = ERR_PTR(-ENOENT);
3721 	struct gpiod_lookup_table *table;
3722 	struct gpiod_lookup *p;
3723 
3724 	table = gpiod_find_lookup_table(dev);
3725 	if (!table)
3726 		return desc;
3727 
3728 	for (p = &table->table[0]; p->key; p++) {
3729 		struct gpio_chip *gc;
3730 
3731 		/* idx must always match exactly */
3732 		if (p->idx != idx)
3733 			continue;
3734 
3735 		/* If the lookup entry has a con_id, require exact match */
3736 		if (p->con_id && (!con_id || strcmp(p->con_id, con_id)))
3737 			continue;
3738 
3739 		if (p->chip_hwnum == U16_MAX) {
3740 			desc = gpio_name_to_desc(p->key);
3741 			if (desc) {
3742 				*flags = p->flags;
3743 				return desc;
3744 			}
3745 
3746 			dev_warn(dev, "cannot find GPIO line %s, deferring\n",
3747 				 p->key);
3748 			return ERR_PTR(-EPROBE_DEFER);
3749 		}
3750 
3751 		gc = find_chip_by_name(p->key);
3752 
3753 		if (!gc) {
3754 			/*
3755 			 * As the lookup table indicates a chip with
3756 			 * p->key should exist, assume it may
3757 			 * still appear later and let the interested
3758 			 * consumer be probed again or let the Deferred
3759 			 * Probe infrastructure handle the error.
3760 			 */
3761 			dev_warn(dev, "cannot find GPIO chip %s, deferring\n",
3762 				 p->key);
3763 			return ERR_PTR(-EPROBE_DEFER);
3764 		}
3765 
3766 		if (gc->ngpio <= p->chip_hwnum) {
3767 			dev_err(dev,
3768 				"requested GPIO %u (%u) is out of range [0..%u] for chip %s\n",
3769 				idx, p->chip_hwnum, gc->ngpio - 1,
3770 				gc->label);
3771 			return ERR_PTR(-EINVAL);
3772 		}
3773 
3774 		desc = gpiochip_get_desc(gc, p->chip_hwnum);
3775 		*flags = p->flags;
3776 
3777 		return desc;
3778 	}
3779 
3780 	return desc;
3781 }
3782 
platform_gpio_count(struct device * dev,const char * con_id)3783 static int platform_gpio_count(struct device *dev, const char *con_id)
3784 {
3785 	struct gpiod_lookup_table *table;
3786 	struct gpiod_lookup *p;
3787 	unsigned int count = 0;
3788 
3789 	table = gpiod_find_lookup_table(dev);
3790 	if (!table)
3791 		return -ENOENT;
3792 
3793 	for (p = &table->table[0]; p->key; p++) {
3794 		if ((con_id && p->con_id && !strcmp(con_id, p->con_id)) ||
3795 		    (!con_id && !p->con_id))
3796 			count++;
3797 	}
3798 	if (!count)
3799 		return -ENOENT;
3800 
3801 	return count;
3802 }
3803 
3804 /**
3805  * fwnode_gpiod_get_index - obtain a GPIO from firmware node
3806  * @fwnode:	handle of the firmware node
3807  * @con_id:	function within the GPIO consumer
3808  * @index:	index of the GPIO to obtain for the consumer
3809  * @flags:	GPIO initialization flags
3810  * @label:	label to attach to the requested GPIO
3811  *
3812  * This function can be used for drivers that get their configuration
3813  * from opaque firmware.
3814  *
3815  * The function properly finds the corresponding GPIO using whatever is the
3816  * underlying firmware interface and then makes sure that the GPIO
3817  * descriptor is requested before it is returned to the caller.
3818  *
3819  * Returns:
3820  * On successful request the GPIO pin is configured in accordance with
3821  * provided @flags.
3822  *
3823  * In case of error an ERR_PTR() is returned.
3824  */
fwnode_gpiod_get_index(struct fwnode_handle * fwnode,const char * con_id,int index,enum gpiod_flags flags,const char * label)3825 struct gpio_desc *fwnode_gpiod_get_index(struct fwnode_handle *fwnode,
3826 					 const char *con_id, int index,
3827 					 enum gpiod_flags flags,
3828 					 const char *label)
3829 {
3830 	struct gpio_desc *desc;
3831 	char prop_name[32]; /* 32 is max size of property name */
3832 	unsigned int i;
3833 
3834 	for (i = 0; i < ARRAY_SIZE(gpio_suffixes); i++) {
3835 		if (con_id)
3836 			snprintf(prop_name, sizeof(prop_name), "%s-%s",
3837 					    con_id, gpio_suffixes[i]);
3838 		else
3839 			snprintf(prop_name, sizeof(prop_name), "%s",
3840 					    gpio_suffixes[i]);
3841 
3842 		desc = fwnode_get_named_gpiod(fwnode, prop_name, index, flags,
3843 					      label);
3844 		if (!gpiod_not_found(desc))
3845 			break;
3846 	}
3847 
3848 	return desc;
3849 }
3850 EXPORT_SYMBOL_GPL(fwnode_gpiod_get_index);
3851 
3852 /**
3853  * gpiod_count - return the number of GPIOs associated with a device / function
3854  *		or -ENOENT if no GPIO has been assigned to the requested function
3855  * @dev:	GPIO consumer, can be NULL for system-global GPIOs
3856  * @con_id:	function within the GPIO consumer
3857  */
gpiod_count(struct device * dev,const char * con_id)3858 int gpiod_count(struct device *dev, const char *con_id)
3859 {
3860 	const struct fwnode_handle *fwnode = dev ? dev_fwnode(dev) : NULL;
3861 	int count = -ENOENT;
3862 
3863 	if (is_of_node(fwnode))
3864 		count = of_gpio_get_count(dev, con_id);
3865 	else if (is_acpi_node(fwnode))
3866 		count = acpi_gpio_count(dev, con_id);
3867 
3868 	if (count < 0)
3869 		count = platform_gpio_count(dev, con_id);
3870 
3871 	return count;
3872 }
3873 EXPORT_SYMBOL_GPL(gpiod_count);
3874 
3875 /**
3876  * gpiod_get - obtain a GPIO for a given GPIO function
3877  * @dev:	GPIO consumer, can be NULL for system-global GPIOs
3878  * @con_id:	function within the GPIO consumer
3879  * @flags:	optional GPIO initialization flags
3880  *
3881  * Return the GPIO descriptor corresponding to the function con_id of device
3882  * dev, -ENOENT if no GPIO has been assigned to the requested function, or
3883  * another IS_ERR() code if an error occurred while trying to acquire the GPIO.
3884  */
gpiod_get(struct device * dev,const char * con_id,enum gpiod_flags flags)3885 struct gpio_desc *__must_check gpiod_get(struct device *dev, const char *con_id,
3886 					 enum gpiod_flags flags)
3887 {
3888 	return gpiod_get_index(dev, con_id, 0, flags);
3889 }
3890 EXPORT_SYMBOL_GPL(gpiod_get);
3891 
3892 /**
3893  * gpiod_get_optional - obtain an optional GPIO for a given GPIO function
3894  * @dev: GPIO consumer, can be NULL for system-global GPIOs
3895  * @con_id: function within the GPIO consumer
3896  * @flags: optional GPIO initialization flags
3897  *
3898  * This is equivalent to gpiod_get(), except that when no GPIO was assigned to
3899  * the requested function it will return NULL. This is convenient for drivers
3900  * that need to handle optional GPIOs.
3901  */
gpiod_get_optional(struct device * dev,const char * con_id,enum gpiod_flags flags)3902 struct gpio_desc *__must_check gpiod_get_optional(struct device *dev,
3903 						  const char *con_id,
3904 						  enum gpiod_flags flags)
3905 {
3906 	return gpiod_get_index_optional(dev, con_id, 0, flags);
3907 }
3908 EXPORT_SYMBOL_GPL(gpiod_get_optional);
3909 
3910 
3911 /**
3912  * gpiod_configure_flags - helper function to configure a given GPIO
3913  * @desc:	gpio whose value will be assigned
3914  * @con_id:	function within the GPIO consumer
3915  * @lflags:	bitmask of gpio_lookup_flags GPIO_* values - returned from
3916  *		of_find_gpio() or of_get_gpio_hog()
3917  * @dflags:	gpiod_flags - optional GPIO initialization flags
3918  *
3919  * Return 0 on success, -ENOENT if no GPIO has been assigned to the
3920  * requested function and/or index, or another IS_ERR() code if an error
3921  * occurred while trying to acquire the GPIO.
3922  */
gpiod_configure_flags(struct gpio_desc * desc,const char * con_id,unsigned long lflags,enum gpiod_flags dflags)3923 int gpiod_configure_flags(struct gpio_desc *desc, const char *con_id,
3924 		unsigned long lflags, enum gpiod_flags dflags)
3925 {
3926 	int ret;
3927 
3928 	if (lflags & GPIO_ACTIVE_LOW)
3929 		set_bit(FLAG_ACTIVE_LOW, &desc->flags);
3930 
3931 	if (lflags & GPIO_OPEN_DRAIN)
3932 		set_bit(FLAG_OPEN_DRAIN, &desc->flags);
3933 	else if (dflags & GPIOD_FLAGS_BIT_OPEN_DRAIN) {
3934 		/*
3935 		 * This enforces open drain mode from the consumer side.
3936 		 * This is necessary for some busses like I2C, but the lookup
3937 		 * should *REALLY* have specified them as open drain in the
3938 		 * first place, so print a little warning here.
3939 		 */
3940 		set_bit(FLAG_OPEN_DRAIN, &desc->flags);
3941 		gpiod_warn(desc,
3942 			   "enforced open drain please flag it properly in DT/ACPI DSDT/board file\n");
3943 	}
3944 
3945 	if (lflags & GPIO_OPEN_SOURCE)
3946 		set_bit(FLAG_OPEN_SOURCE, &desc->flags);
3947 
3948 	if ((lflags & GPIO_PULL_UP) && (lflags & GPIO_PULL_DOWN)) {
3949 		gpiod_err(desc,
3950 			  "both pull-up and pull-down enabled, invalid configuration\n");
3951 		return -EINVAL;
3952 	}
3953 
3954 	if (lflags & GPIO_PULL_UP)
3955 		set_bit(FLAG_PULL_UP, &desc->flags);
3956 	else if (lflags & GPIO_PULL_DOWN)
3957 		set_bit(FLAG_PULL_DOWN, &desc->flags);
3958 
3959 	ret = gpiod_set_transitory(desc, (lflags & GPIO_TRANSITORY));
3960 	if (ret < 0)
3961 		return ret;
3962 
3963 	/* No particular flag request, return here... */
3964 	if (!(dflags & GPIOD_FLAGS_BIT_DIR_SET)) {
3965 		gpiod_dbg(desc, "no flags found for %s\n", con_id);
3966 		return 0;
3967 	}
3968 
3969 	/* Process flags */
3970 	if (dflags & GPIOD_FLAGS_BIT_DIR_OUT)
3971 		ret = gpiod_direction_output(desc,
3972 				!!(dflags & GPIOD_FLAGS_BIT_DIR_VAL));
3973 	else
3974 		ret = gpiod_direction_input(desc);
3975 
3976 	return ret;
3977 }
3978 
3979 /**
3980  * gpiod_get_index - obtain a GPIO from a multi-index GPIO function
3981  * @dev:	GPIO consumer, can be NULL for system-global GPIOs
3982  * @con_id:	function within the GPIO consumer
3983  * @idx:	index of the GPIO to obtain in the consumer
3984  * @flags:	optional GPIO initialization flags
3985  *
3986  * This variant of gpiod_get() allows to access GPIOs other than the first
3987  * defined one for functions that define several GPIOs.
3988  *
3989  * Return a valid GPIO descriptor, -ENOENT if no GPIO has been assigned to the
3990  * requested function and/or index, or another IS_ERR() code if an error
3991  * occurred while trying to acquire the GPIO.
3992  */
gpiod_get_index(struct device * dev,const char * con_id,unsigned int idx,enum gpiod_flags flags)3993 struct gpio_desc *__must_check gpiod_get_index(struct device *dev,
3994 					       const char *con_id,
3995 					       unsigned int idx,
3996 					       enum gpiod_flags flags)
3997 {
3998 	unsigned long lookupflags = GPIO_LOOKUP_FLAGS_DEFAULT;
3999 	struct gpio_desc *desc = NULL;
4000 	int ret;
4001 	/* Maybe we have a device name, maybe not */
4002 	const char *devname = dev ? dev_name(dev) : "?";
4003 	const struct fwnode_handle *fwnode = dev ? dev_fwnode(dev) : NULL;
4004 
4005 	dev_dbg(dev, "GPIO lookup for consumer %s\n", con_id);
4006 
4007 	/* Using device tree? */
4008 	if (is_of_node(fwnode)) {
4009 		dev_dbg(dev, "using device tree for GPIO lookup\n");
4010 		desc = of_find_gpio(dev, con_id, idx, &lookupflags);
4011 	} else if (is_acpi_node(fwnode)) {
4012 		dev_dbg(dev, "using ACPI for GPIO lookup\n");
4013 		desc = acpi_find_gpio(dev, con_id, idx, &flags, &lookupflags);
4014 	}
4015 
4016 	/*
4017 	 * Either we are not using DT or ACPI, or their lookup did not return
4018 	 * a result. In that case, use platform lookup as a fallback.
4019 	 */
4020 	if (!desc || gpiod_not_found(desc)) {
4021 		dev_dbg(dev, "using lookup tables for GPIO lookup\n");
4022 		desc = gpiod_find(dev, con_id, idx, &lookupflags);
4023 	}
4024 
4025 	if (IS_ERR(desc)) {
4026 		dev_dbg(dev, "No GPIO consumer %s found\n", con_id);
4027 		return desc;
4028 	}
4029 
4030 	/*
4031 	 * If a connection label was passed use that, else attempt to use
4032 	 * the device name as label
4033 	 */
4034 	ret = gpiod_request(desc, con_id ?: devname);
4035 	if (ret) {
4036 		if (!(ret == -EBUSY && flags & GPIOD_FLAGS_BIT_NONEXCLUSIVE))
4037 			return ERR_PTR(ret);
4038 
4039 		/*
4040 		 * This happens when there are several consumers for
4041 		 * the same GPIO line: we just return here without
4042 		 * further initialization. It is a bit of a hack.
4043 		 * This is necessary to support fixed regulators.
4044 		 *
4045 		 * FIXME: Make this more sane and safe.
4046 		 */
4047 		dev_info(dev, "nonexclusive access to GPIO for %s\n", con_id ?: devname);
4048 		return desc;
4049 	}
4050 
4051 	ret = gpiod_configure_flags(desc, con_id, lookupflags, flags);
4052 	if (ret < 0) {
4053 		dev_dbg(dev, "setup of GPIO %s failed\n", con_id);
4054 		gpiod_put(desc);
4055 		return ERR_PTR(ret);
4056 	}
4057 
4058 	blocking_notifier_call_chain(&desc->gdev->notifier,
4059 				     GPIOLINE_CHANGED_REQUESTED, desc);
4060 
4061 	return desc;
4062 }
4063 EXPORT_SYMBOL_GPL(gpiod_get_index);
4064 
4065 /**
4066  * fwnode_get_named_gpiod - obtain a GPIO from firmware node
4067  * @fwnode:	handle of the firmware node
4068  * @propname:	name of the firmware property representing the GPIO
4069  * @index:	index of the GPIO to obtain for the consumer
4070  * @dflags:	GPIO initialization flags
4071  * @label:	label to attach to the requested GPIO
4072  *
4073  * This function can be used for drivers that get their configuration
4074  * from opaque firmware.
4075  *
4076  * The function properly finds the corresponding GPIO using whatever is the
4077  * underlying firmware interface and then makes sure that the GPIO
4078  * descriptor is requested before it is returned to the caller.
4079  *
4080  * Returns:
4081  * On successful request the GPIO pin is configured in accordance with
4082  * provided @dflags.
4083  *
4084  * In case of error an ERR_PTR() is returned.
4085  */
fwnode_get_named_gpiod(struct fwnode_handle * fwnode,const char * propname,int index,enum gpiod_flags dflags,const char * label)4086 struct gpio_desc *fwnode_get_named_gpiod(struct fwnode_handle *fwnode,
4087 					 const char *propname, int index,
4088 					 enum gpiod_flags dflags,
4089 					 const char *label)
4090 {
4091 	unsigned long lflags = GPIO_LOOKUP_FLAGS_DEFAULT;
4092 	struct gpio_desc *desc = ERR_PTR(-ENODEV);
4093 	int ret;
4094 
4095 	if (is_of_node(fwnode)) {
4096 		desc = gpiod_get_from_of_node(to_of_node(fwnode),
4097 					      propname, index,
4098 					      dflags,
4099 					      label);
4100 		return desc;
4101 	} else if (is_acpi_node(fwnode)) {
4102 		struct acpi_gpio_info info;
4103 
4104 		desc = acpi_node_get_gpiod(fwnode, propname, index, &info);
4105 		if (IS_ERR(desc))
4106 			return desc;
4107 
4108 		acpi_gpio_update_gpiod_flags(&dflags, &info);
4109 		acpi_gpio_update_gpiod_lookup_flags(&lflags, &info);
4110 	} else
4111 		return ERR_PTR(-EINVAL);
4112 
4113 	/* Currently only ACPI takes this path */
4114 	ret = gpiod_request(desc, label);
4115 	if (ret)
4116 		return ERR_PTR(ret);
4117 
4118 	ret = gpiod_configure_flags(desc, propname, lflags, dflags);
4119 	if (ret < 0) {
4120 		gpiod_put(desc);
4121 		return ERR_PTR(ret);
4122 	}
4123 
4124 	blocking_notifier_call_chain(&desc->gdev->notifier,
4125 				     GPIOLINE_CHANGED_REQUESTED, desc);
4126 
4127 	return desc;
4128 }
4129 EXPORT_SYMBOL_GPL(fwnode_get_named_gpiod);
4130 
4131 /**
4132  * gpiod_get_index_optional - obtain an optional GPIO from a multi-index GPIO
4133  *                            function
4134  * @dev: GPIO consumer, can be NULL for system-global GPIOs
4135  * @con_id: function within the GPIO consumer
4136  * @index: index of the GPIO to obtain in the consumer
4137  * @flags: optional GPIO initialization flags
4138  *
4139  * This is equivalent to gpiod_get_index(), except that when no GPIO with the
4140  * specified index was assigned to the requested function it will return NULL.
4141  * This is convenient for drivers that need to handle optional GPIOs.
4142  */
gpiod_get_index_optional(struct device * dev,const char * con_id,unsigned int index,enum gpiod_flags flags)4143 struct gpio_desc *__must_check gpiod_get_index_optional(struct device *dev,
4144 							const char *con_id,
4145 							unsigned int index,
4146 							enum gpiod_flags flags)
4147 {
4148 	struct gpio_desc *desc;
4149 
4150 	desc = gpiod_get_index(dev, con_id, index, flags);
4151 	if (gpiod_not_found(desc))
4152 		return NULL;
4153 
4154 	return desc;
4155 }
4156 EXPORT_SYMBOL_GPL(gpiod_get_index_optional);
4157 
4158 /**
4159  * gpiod_hog - Hog the specified GPIO desc given the provided flags
4160  * @desc:	gpio whose value will be assigned
4161  * @name:	gpio line name
4162  * @lflags:	bitmask of gpio_lookup_flags GPIO_* values - returned from
4163  *		of_find_gpio() or of_get_gpio_hog()
4164  * @dflags:	gpiod_flags - optional GPIO initialization flags
4165  */
gpiod_hog(struct gpio_desc * desc,const char * name,unsigned long lflags,enum gpiod_flags dflags)4166 int gpiod_hog(struct gpio_desc *desc, const char *name,
4167 	      unsigned long lflags, enum gpiod_flags dflags)
4168 {
4169 	struct gpio_chip *gc;
4170 	struct gpio_desc *local_desc;
4171 	int hwnum;
4172 	int ret;
4173 
4174 	gc = gpiod_to_chip(desc);
4175 	hwnum = gpio_chip_hwgpio(desc);
4176 
4177 	local_desc = gpiochip_request_own_desc(gc, hwnum, name,
4178 					       lflags, dflags);
4179 	if (IS_ERR(local_desc)) {
4180 		ret = PTR_ERR(local_desc);
4181 		pr_err("requesting hog GPIO %s (chip %s, offset %d) failed, %d\n",
4182 		       name, gc->label, hwnum, ret);
4183 		return ret;
4184 	}
4185 
4186 	/* Mark GPIO as hogged so it can be identified and removed later */
4187 	set_bit(FLAG_IS_HOGGED, &desc->flags);
4188 
4189 	gpiod_info(desc, "hogged as %s%s\n",
4190 		(dflags & GPIOD_FLAGS_BIT_DIR_OUT) ? "output" : "input",
4191 		(dflags & GPIOD_FLAGS_BIT_DIR_OUT) ?
4192 		  (dflags & GPIOD_FLAGS_BIT_DIR_VAL) ? "/high" : "/low" : "");
4193 
4194 	return 0;
4195 }
4196 
4197 /**
4198  * gpiochip_free_hogs - Scan gpio-controller chip and release GPIO hog
4199  * @gc:	gpio chip to act on
4200  */
gpiochip_free_hogs(struct gpio_chip * gc)4201 static void gpiochip_free_hogs(struct gpio_chip *gc)
4202 {
4203 	struct gpio_desc *desc;
4204 
4205 	for_each_gpio_desc_with_flag(gc, desc, FLAG_IS_HOGGED)
4206 		gpiochip_free_own_desc(desc);
4207 }
4208 
4209 /**
4210  * gpiod_get_array - obtain multiple GPIOs from a multi-index GPIO function
4211  * @dev:	GPIO consumer, can be NULL for system-global GPIOs
4212  * @con_id:	function within the GPIO consumer
4213  * @flags:	optional GPIO initialization flags
4214  *
4215  * This function acquires all the GPIOs defined under a given function.
4216  *
4217  * Return a struct gpio_descs containing an array of descriptors, -ENOENT if
4218  * no GPIO has been assigned to the requested function, or another IS_ERR()
4219  * code if an error occurred while trying to acquire the GPIOs.
4220  */
gpiod_get_array(struct device * dev,const char * con_id,enum gpiod_flags flags)4221 struct gpio_descs *__must_check gpiod_get_array(struct device *dev,
4222 						const char *con_id,
4223 						enum gpiod_flags flags)
4224 {
4225 	struct gpio_desc *desc;
4226 	struct gpio_descs *descs;
4227 	struct gpio_array *array_info = NULL;
4228 	struct gpio_chip *gc;
4229 	int count, bitmap_size;
4230 
4231 	count = gpiod_count(dev, con_id);
4232 	if (count < 0)
4233 		return ERR_PTR(count);
4234 
4235 	descs = kzalloc(struct_size(descs, desc, count), GFP_KERNEL);
4236 	if (!descs)
4237 		return ERR_PTR(-ENOMEM);
4238 
4239 	for (descs->ndescs = 0; descs->ndescs < count; ) {
4240 		desc = gpiod_get_index(dev, con_id, descs->ndescs, flags);
4241 		if (IS_ERR(desc)) {
4242 			gpiod_put_array(descs);
4243 			return ERR_CAST(desc);
4244 		}
4245 
4246 		descs->desc[descs->ndescs] = desc;
4247 
4248 		gc = gpiod_to_chip(desc);
4249 		/*
4250 		 * If pin hardware number of array member 0 is also 0, select
4251 		 * its chip as a candidate for fast bitmap processing path.
4252 		 */
4253 		if (descs->ndescs == 0 && gpio_chip_hwgpio(desc) == 0) {
4254 			struct gpio_descs *array;
4255 
4256 			bitmap_size = BITS_TO_LONGS(gc->ngpio > count ?
4257 						    gc->ngpio : count);
4258 
4259 			array = kzalloc(struct_size(descs, desc, count) +
4260 					struct_size(array_info, invert_mask,
4261 					3 * bitmap_size), GFP_KERNEL);
4262 			if (!array) {
4263 				gpiod_put_array(descs);
4264 				return ERR_PTR(-ENOMEM);
4265 			}
4266 
4267 			memcpy(array, descs,
4268 			       struct_size(descs, desc, descs->ndescs + 1));
4269 			kfree(descs);
4270 
4271 			descs = array;
4272 			array_info = (void *)(descs->desc + count);
4273 			array_info->get_mask = array_info->invert_mask +
4274 						  bitmap_size;
4275 			array_info->set_mask = array_info->get_mask +
4276 						  bitmap_size;
4277 
4278 			array_info->desc = descs->desc;
4279 			array_info->size = count;
4280 			array_info->chip = gc;
4281 			bitmap_set(array_info->get_mask, descs->ndescs,
4282 				   count - descs->ndescs);
4283 			bitmap_set(array_info->set_mask, descs->ndescs,
4284 				   count - descs->ndescs);
4285 			descs->info = array_info;
4286 		}
4287 		/* Unmark array members which don't belong to the 'fast' chip */
4288 		if (array_info && array_info->chip != gc) {
4289 			__clear_bit(descs->ndescs, array_info->get_mask);
4290 			__clear_bit(descs->ndescs, array_info->set_mask);
4291 		}
4292 		/*
4293 		 * Detect array members which belong to the 'fast' chip
4294 		 * but their pins are not in hardware order.
4295 		 */
4296 		else if (array_info &&
4297 			   gpio_chip_hwgpio(desc) != descs->ndescs) {
4298 			/*
4299 			 * Don't use fast path if all array members processed so
4300 			 * far belong to the same chip as this one but its pin
4301 			 * hardware number is different from its array index.
4302 			 */
4303 			if (bitmap_full(array_info->get_mask, descs->ndescs)) {
4304 				array_info = NULL;
4305 			} else {
4306 				__clear_bit(descs->ndescs,
4307 					    array_info->get_mask);
4308 				__clear_bit(descs->ndescs,
4309 					    array_info->set_mask);
4310 			}
4311 		} else if (array_info) {
4312 			/* Exclude open drain or open source from fast output */
4313 			if (gpiochip_line_is_open_drain(gc, descs->ndescs) ||
4314 			    gpiochip_line_is_open_source(gc, descs->ndescs))
4315 				__clear_bit(descs->ndescs,
4316 					    array_info->set_mask);
4317 			/* Identify 'fast' pins which require invertion */
4318 			if (gpiod_is_active_low(desc))
4319 				__set_bit(descs->ndescs,
4320 					  array_info->invert_mask);
4321 		}
4322 
4323 		descs->ndescs++;
4324 	}
4325 	if (array_info)
4326 		dev_dbg(dev,
4327 			"GPIO array info: chip=%s, size=%d, get_mask=%lx, set_mask=%lx, invert_mask=%lx\n",
4328 			array_info->chip->label, array_info->size,
4329 			*array_info->get_mask, *array_info->set_mask,
4330 			*array_info->invert_mask);
4331 	return descs;
4332 }
4333 EXPORT_SYMBOL_GPL(gpiod_get_array);
4334 
4335 /**
4336  * gpiod_get_array_optional - obtain multiple GPIOs from a multi-index GPIO
4337  *                            function
4338  * @dev:	GPIO consumer, can be NULL for system-global GPIOs
4339  * @con_id:	function within the GPIO consumer
4340  * @flags:	optional GPIO initialization flags
4341  *
4342  * This is equivalent to gpiod_get_array(), except that when no GPIO was
4343  * assigned to the requested function it will return NULL.
4344  */
gpiod_get_array_optional(struct device * dev,const char * con_id,enum gpiod_flags flags)4345 struct gpio_descs *__must_check gpiod_get_array_optional(struct device *dev,
4346 							const char *con_id,
4347 							enum gpiod_flags flags)
4348 {
4349 	struct gpio_descs *descs;
4350 
4351 	descs = gpiod_get_array(dev, con_id, flags);
4352 	if (gpiod_not_found(descs))
4353 		return NULL;
4354 
4355 	return descs;
4356 }
4357 EXPORT_SYMBOL_GPL(gpiod_get_array_optional);
4358 
4359 /**
4360  * gpiod_put - dispose of a GPIO descriptor
4361  * @desc:	GPIO descriptor to dispose of
4362  *
4363  * No descriptor can be used after gpiod_put() has been called on it.
4364  */
gpiod_put(struct gpio_desc * desc)4365 void gpiod_put(struct gpio_desc *desc)
4366 {
4367 	if (desc)
4368 		gpiod_free(desc);
4369 }
4370 EXPORT_SYMBOL_GPL(gpiod_put);
4371 
4372 /**
4373  * gpiod_put_array - dispose of multiple GPIO descriptors
4374  * @descs:	struct gpio_descs containing an array of descriptors
4375  */
gpiod_put_array(struct gpio_descs * descs)4376 void gpiod_put_array(struct gpio_descs *descs)
4377 {
4378 	unsigned int i;
4379 
4380 	for (i = 0; i < descs->ndescs; i++)
4381 		gpiod_put(descs->desc[i]);
4382 
4383 	kfree(descs);
4384 }
4385 EXPORT_SYMBOL_GPL(gpiod_put_array);
4386 
4387 
gpio_bus_match(struct device * dev,struct device_driver * drv)4388 static int gpio_bus_match(struct device *dev, struct device_driver *drv)
4389 {
4390 	struct fwnode_handle *fwnode = dev_fwnode(dev);
4391 
4392 	/*
4393 	 * Only match if the fwnode doesn't already have a proper struct device
4394 	 * created for it.
4395 	 */
4396 	if (fwnode && fwnode->dev != dev)
4397 		return 0;
4398 	return 1;
4399 }
4400 
gpio_stub_drv_probe(struct device * dev)4401 static int gpio_stub_drv_probe(struct device *dev)
4402 {
4403 	/*
4404 	 * The DT node of some GPIO chips have a "compatible" property, but
4405 	 * never have a struct device added and probed by a driver to register
4406 	 * the GPIO chip with gpiolib. In such cases, fw_devlink=on will cause
4407 	 * the consumers of the GPIO chip to get probe deferred forever because
4408 	 * they will be waiting for a device associated with the GPIO chip
4409 	 * firmware node to get added and bound to a driver.
4410 	 *
4411 	 * To allow these consumers to probe, we associate the struct
4412 	 * gpio_device of the GPIO chip with the firmware node and then simply
4413 	 * bind it to this stub driver.
4414 	 */
4415 	return 0;
4416 }
4417 
4418 static struct device_driver gpio_stub_drv = {
4419 	.name = "gpio_stub_drv",
4420 	.bus = &gpio_bus_type,
4421 	.probe = gpio_stub_drv_probe,
4422 };
4423 
gpiolib_dev_init(void)4424 static int __init gpiolib_dev_init(void)
4425 {
4426 	int ret;
4427 
4428 	/* Register GPIO sysfs bus */
4429 	ret = bus_register(&gpio_bus_type);
4430 	if (ret < 0) {
4431 		pr_err("gpiolib: could not register GPIO bus type\n");
4432 		return ret;
4433 	}
4434 
4435 	ret = driver_register(&gpio_stub_drv);
4436 	if (ret < 0) {
4437 		pr_err("gpiolib: could not register GPIO stub driver\n");
4438 		bus_unregister(&gpio_bus_type);
4439 		return ret;
4440 	}
4441 
4442 	ret = alloc_chrdev_region(&gpio_devt, 0, GPIO_DEV_MAX, GPIOCHIP_NAME);
4443 	if (ret < 0) {
4444 		pr_err("gpiolib: failed to allocate char dev region\n");
4445 		driver_unregister(&gpio_stub_drv);
4446 		bus_unregister(&gpio_bus_type);
4447 		return ret;
4448 	}
4449 
4450 	gpiolib_initialized = true;
4451 	gpiochip_setup_devs();
4452 
4453 #if IS_ENABLED(CONFIG_OF_DYNAMIC) && IS_ENABLED(CONFIG_OF_GPIO)
4454 	WARN_ON(of_reconfig_notifier_register(&gpio_of_notifier));
4455 #endif /* CONFIG_OF_DYNAMIC && CONFIG_OF_GPIO */
4456 
4457 	return ret;
4458 }
4459 core_initcall(gpiolib_dev_init);
4460 
4461 #ifdef CONFIG_DEBUG_FS
4462 
gpiolib_dbg_show(struct seq_file * s,struct gpio_device * gdev)4463 static void gpiolib_dbg_show(struct seq_file *s, struct gpio_device *gdev)
4464 {
4465 	struct gpio_chip	*gc = gdev->chip;
4466 	struct gpio_desc	*desc;
4467 	unsigned		gpio = gdev->base;
4468 	int			value;
4469 	bool			is_out;
4470 	bool			is_irq;
4471 	bool			active_low;
4472 
4473 	for_each_gpio_desc(gc, desc) {
4474 		if (test_bit(FLAG_REQUESTED, &desc->flags)) {
4475 			gpiod_get_direction(desc);
4476 			is_out = test_bit(FLAG_IS_OUT, &desc->flags);
4477 			value = gpio_chip_get_value(gc, desc);
4478 			is_irq = test_bit(FLAG_USED_AS_IRQ, &desc->flags);
4479 			active_low = test_bit(FLAG_ACTIVE_LOW, &desc->flags);
4480 			seq_printf(s, " gpio-%-3d (%-20.20s|%-20.20s) %s %s %s%s\n",
4481 				   gpio, desc->name ?: "", desc->label,
4482 				   is_out ? "out" : "in ",
4483 				   value >= 0 ? (value ? "hi" : "lo") : "?  ",
4484 				   is_irq ? "IRQ " : "",
4485 				   active_low ? "ACTIVE LOW" : "");
4486 		} else if (desc->name) {
4487 			seq_printf(s, " gpio-%-3d (%-20.20s)\n", gpio, desc->name);
4488 		}
4489 
4490 		gpio++;
4491 	}
4492 }
4493 
gpiolib_seq_start(struct seq_file * s,loff_t * pos)4494 static void *gpiolib_seq_start(struct seq_file *s, loff_t *pos)
4495 {
4496 	unsigned long flags;
4497 	struct gpio_device *gdev = NULL;
4498 	loff_t index = *pos;
4499 
4500 	s->private = "";
4501 
4502 	spin_lock_irqsave(&gpio_lock, flags);
4503 	list_for_each_entry(gdev, &gpio_devices, list)
4504 		if (index-- == 0) {
4505 			spin_unlock_irqrestore(&gpio_lock, flags);
4506 			return gdev;
4507 		}
4508 	spin_unlock_irqrestore(&gpio_lock, flags);
4509 
4510 	return NULL;
4511 }
4512 
gpiolib_seq_next(struct seq_file * s,void * v,loff_t * pos)4513 static void *gpiolib_seq_next(struct seq_file *s, void *v, loff_t *pos)
4514 {
4515 	unsigned long flags;
4516 	struct gpio_device *gdev = v;
4517 	void *ret = NULL;
4518 
4519 	spin_lock_irqsave(&gpio_lock, flags);
4520 	if (list_is_last(&gdev->list, &gpio_devices))
4521 		ret = NULL;
4522 	else
4523 		ret = list_first_entry(&gdev->list, struct gpio_device, list);
4524 	spin_unlock_irqrestore(&gpio_lock, flags);
4525 
4526 	s->private = "\n";
4527 	++*pos;
4528 
4529 	return ret;
4530 }
4531 
gpiolib_seq_stop(struct seq_file * s,void * v)4532 static void gpiolib_seq_stop(struct seq_file *s, void *v)
4533 {
4534 }
4535 
gpiolib_seq_show(struct seq_file * s,void * v)4536 static int gpiolib_seq_show(struct seq_file *s, void *v)
4537 {
4538 	struct gpio_device *gdev = v;
4539 	struct gpio_chip *gc = gdev->chip;
4540 	struct device *parent;
4541 
4542 	if (!gc) {
4543 		seq_printf(s, "%s%s: (dangling chip)", (char *)s->private,
4544 			   dev_name(&gdev->dev));
4545 		return 0;
4546 	}
4547 
4548 	seq_printf(s, "%s%s: GPIOs %d-%d", (char *)s->private,
4549 		   dev_name(&gdev->dev),
4550 		   gdev->base, gdev->base + gdev->ngpio - 1);
4551 	parent = gc->parent;
4552 	if (parent)
4553 		seq_printf(s, ", parent: %s/%s",
4554 			   parent->bus ? parent->bus->name : "no-bus",
4555 			   dev_name(parent));
4556 	if (gc->label)
4557 		seq_printf(s, ", %s", gc->label);
4558 	if (gc->can_sleep)
4559 		seq_printf(s, ", can sleep");
4560 	seq_printf(s, ":\n");
4561 
4562 	if (gc->dbg_show)
4563 		gc->dbg_show(s, gc);
4564 	else
4565 		gpiolib_dbg_show(s, gdev);
4566 
4567 	return 0;
4568 }
4569 
4570 static const struct seq_operations gpiolib_sops = {
4571 	.start = gpiolib_seq_start,
4572 	.next = gpiolib_seq_next,
4573 	.stop = gpiolib_seq_stop,
4574 	.show = gpiolib_seq_show,
4575 };
4576 DEFINE_SEQ_ATTRIBUTE(gpiolib);
4577 
gpiolib_debugfs_init(void)4578 static int __init gpiolib_debugfs_init(void)
4579 {
4580 	/* /sys/kernel/debug/gpio */
4581 	debugfs_create_file("gpio", 0444, NULL, NULL, &gpiolib_fops);
4582 	return 0;
4583 }
4584 subsys_initcall(gpiolib_debugfs_init);
4585 
4586 #endif	/* DEBUG_FS */
4587