1 /*
2  * Driver for keys on GPIO lines capable of generating interrupts.
3  *
4  * Copyright 2005 Phil Blundell
5  * Copyright 2010, 2011 David Jander <david@protonic.nl>
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License version 2 as
9  * published by the Free Software Foundation.
10  */
11 
12 #include <linux/module.h>
13 
14 #include <linux/init.h>
15 #include <linux/fs.h>
16 #include <linux/interrupt.h>
17 #include <linux/irq.h>
18 #include <linux/sched.h>
19 #include <linux/pm.h>
20 #include <linux/slab.h>
21 #include <linux/sysctl.h>
22 #include <linux/proc_fs.h>
23 #include <linux/delay.h>
24 #include <linux/platform_device.h>
25 #include <linux/input.h>
26 #include <linux/gpio_keys.h>
27 #include <linux/workqueue.h>
28 #include <linux/gpio.h>
29 #include <linux/of_platform.h>
30 #include <linux/of_gpio.h>
31 #include <linux/spinlock.h>
32 
33 struct gpio_button_data {
34 	const struct gpio_keys_button *button;
35 	struct input_dev *input;
36 	struct timer_list timer;
37 	struct work_struct work;
38 	unsigned int timer_debounce;	/* in msecs */
39 	unsigned int irq;
40 	spinlock_t lock;
41 	bool disabled;
42 	bool key_pressed;
43 };
44 
45 struct gpio_keys_drvdata {
46 	struct input_dev *input;
47 	struct mutex disable_lock;
48 	unsigned int n_buttons;
49 	int (*enable)(struct device *dev);
50 	void (*disable)(struct device *dev);
51 	struct gpio_button_data data[0];
52 };
53 
54 /*
55  * SYSFS interface for enabling/disabling keys and switches:
56  *
57  * There are 4 attributes under /sys/devices/platform/gpio-keys/
58  *	keys [ro]              - bitmap of keys (EV_KEY) which can be
59  *	                         disabled
60  *	switches [ro]          - bitmap of switches (EV_SW) which can be
61  *	                         disabled
62  *	disabled_keys [rw]     - bitmap of keys currently disabled
63  *	disabled_switches [rw] - bitmap of switches currently disabled
64  *
65  * Userland can change these values and hence disable event generation
66  * for each key (or switch). Disabling a key means its interrupt line
67  * is disabled.
68  *
69  * For example, if we have following switches set up as gpio-keys:
70  *	SW_DOCK = 5
71  *	SW_CAMERA_LENS_COVER = 9
72  *	SW_KEYPAD_SLIDE = 10
73  *	SW_FRONT_PROXIMITY = 11
74  * This is read from switches:
75  *	11-9,5
76  * Next we want to disable proximity (11) and dock (5), we write:
77  *	11,5
78  * to file disabled_switches. Now proximity and dock IRQs are disabled.
79  * This can be verified by reading the file disabled_switches:
80  *	11,5
81  * If we now want to enable proximity (11) switch we write:
82  *	5
83  * to disabled_switches.
84  *
85  * We can disable only those keys which don't allow sharing the irq.
86  */
87 
88 /**
89  * get_n_events_by_type() - returns maximum number of events per @type
90  * @type: type of button (%EV_KEY, %EV_SW)
91  *
92  * Return value of this function can be used to allocate bitmap
93  * large enough to hold all bits for given type.
94  */
get_n_events_by_type(int type)95 static inline int get_n_events_by_type(int type)
96 {
97 	BUG_ON(type != EV_SW && type != EV_KEY);
98 
99 	return (type == EV_KEY) ? KEY_CNT : SW_CNT;
100 }
101 
102 /**
103  * gpio_keys_disable_button() - disables given GPIO button
104  * @bdata: button data for button to be disabled
105  *
106  * Disables button pointed by @bdata. This is done by masking
107  * IRQ line. After this function is called, button won't generate
108  * input events anymore. Note that one can only disable buttons
109  * that don't share IRQs.
110  *
111  * Make sure that @bdata->disable_lock is locked when entering
112  * this function to avoid races when concurrent threads are
113  * disabling buttons at the same time.
114  */
gpio_keys_disable_button(struct gpio_button_data * bdata)115 static void gpio_keys_disable_button(struct gpio_button_data *bdata)
116 {
117 	if (!bdata->disabled) {
118 		/*
119 		 * Disable IRQ and possible debouncing timer.
120 		 */
121 		disable_irq(bdata->irq);
122 		if (bdata->timer_debounce)
123 			del_timer_sync(&bdata->timer);
124 
125 		bdata->disabled = true;
126 	}
127 }
128 
129 /**
130  * gpio_keys_enable_button() - enables given GPIO button
131  * @bdata: button data for button to be disabled
132  *
133  * Enables given button pointed by @bdata.
134  *
135  * Make sure that @bdata->disable_lock is locked when entering
136  * this function to avoid races with concurrent threads trying
137  * to enable the same button at the same time.
138  */
gpio_keys_enable_button(struct gpio_button_data * bdata)139 static void gpio_keys_enable_button(struct gpio_button_data *bdata)
140 {
141 	if (bdata->disabled) {
142 		enable_irq(bdata->irq);
143 		bdata->disabled = false;
144 	}
145 }
146 
147 /**
148  * gpio_keys_attr_show_helper() - fill in stringified bitmap of buttons
149  * @ddata: pointer to drvdata
150  * @buf: buffer where stringified bitmap is written
151  * @type: button type (%EV_KEY, %EV_SW)
152  * @only_disabled: does caller want only those buttons that are
153  *                 currently disabled or all buttons that can be
154  *                 disabled
155  *
156  * This function writes buttons that can be disabled to @buf. If
157  * @only_disabled is true, then @buf contains only those buttons
158  * that are currently disabled. Returns 0 on success or negative
159  * errno on failure.
160  */
gpio_keys_attr_show_helper(struct gpio_keys_drvdata * ddata,char * buf,unsigned int type,bool only_disabled)161 static ssize_t gpio_keys_attr_show_helper(struct gpio_keys_drvdata *ddata,
162 					  char *buf, unsigned int type,
163 					  bool only_disabled)
164 {
165 	int n_events = get_n_events_by_type(type);
166 	unsigned long *bits;
167 	ssize_t ret;
168 	int i;
169 
170 	bits = kcalloc(BITS_TO_LONGS(n_events), sizeof(*bits), GFP_KERNEL);
171 	if (!bits)
172 		return -ENOMEM;
173 
174 	for (i = 0; i < ddata->n_buttons; i++) {
175 		struct gpio_button_data *bdata = &ddata->data[i];
176 
177 		if (bdata->button->type != type)
178 			continue;
179 
180 		if (only_disabled && !bdata->disabled)
181 			continue;
182 
183 		__set_bit(bdata->button->code, bits);
184 	}
185 
186 	ret = bitmap_scnlistprintf(buf, PAGE_SIZE - 2, bits, n_events);
187 	buf[ret++] = '\n';
188 	buf[ret] = '\0';
189 
190 	kfree(bits);
191 
192 	return ret;
193 }
194 
195 /**
196  * gpio_keys_attr_store_helper() - enable/disable buttons based on given bitmap
197  * @ddata: pointer to drvdata
198  * @buf: buffer from userspace that contains stringified bitmap
199  * @type: button type (%EV_KEY, %EV_SW)
200  *
201  * This function parses stringified bitmap from @buf and disables/enables
202  * GPIO buttons accordingly. Returns 0 on success and negative error
203  * on failure.
204  */
gpio_keys_attr_store_helper(struct gpio_keys_drvdata * ddata,const char * buf,unsigned int type)205 static ssize_t gpio_keys_attr_store_helper(struct gpio_keys_drvdata *ddata,
206 					   const char *buf, unsigned int type)
207 {
208 	int n_events = get_n_events_by_type(type);
209 	unsigned long *bits;
210 	ssize_t error;
211 	int i;
212 
213 	bits = kcalloc(BITS_TO_LONGS(n_events), sizeof(*bits), GFP_KERNEL);
214 	if (!bits)
215 		return -ENOMEM;
216 
217 	error = bitmap_parselist(buf, bits, n_events);
218 	if (error)
219 		goto out;
220 
221 	/* First validate */
222 	for (i = 0; i < ddata->n_buttons; i++) {
223 		struct gpio_button_data *bdata = &ddata->data[i];
224 
225 		if (bdata->button->type != type)
226 			continue;
227 
228 		if (test_bit(bdata->button->code, bits) &&
229 		    !bdata->button->can_disable) {
230 			error = -EINVAL;
231 			goto out;
232 		}
233 	}
234 
235 	mutex_lock(&ddata->disable_lock);
236 
237 	for (i = 0; i < ddata->n_buttons; i++) {
238 		struct gpio_button_data *bdata = &ddata->data[i];
239 
240 		if (bdata->button->type != type)
241 			continue;
242 
243 		if (test_bit(bdata->button->code, bits))
244 			gpio_keys_disable_button(bdata);
245 		else
246 			gpio_keys_enable_button(bdata);
247 	}
248 
249 	mutex_unlock(&ddata->disable_lock);
250 
251 out:
252 	kfree(bits);
253 	return error;
254 }
255 
256 #define ATTR_SHOW_FN(name, type, only_disabled)				\
257 static ssize_t gpio_keys_show_##name(struct device *dev,		\
258 				     struct device_attribute *attr,	\
259 				     char *buf)				\
260 {									\
261 	struct platform_device *pdev = to_platform_device(dev);		\
262 	struct gpio_keys_drvdata *ddata = platform_get_drvdata(pdev);	\
263 									\
264 	return gpio_keys_attr_show_helper(ddata, buf,			\
265 					  type, only_disabled);		\
266 }
267 
268 ATTR_SHOW_FN(keys, EV_KEY, false);
269 ATTR_SHOW_FN(switches, EV_SW, false);
270 ATTR_SHOW_FN(disabled_keys, EV_KEY, true);
271 ATTR_SHOW_FN(disabled_switches, EV_SW, true);
272 
273 /*
274  * ATTRIBUTES:
275  *
276  * /sys/devices/platform/gpio-keys/keys [ro]
277  * /sys/devices/platform/gpio-keys/switches [ro]
278  */
279 static DEVICE_ATTR(keys, S_IRUGO, gpio_keys_show_keys, NULL);
280 static DEVICE_ATTR(switches, S_IRUGO, gpio_keys_show_switches, NULL);
281 
282 #define ATTR_STORE_FN(name, type)					\
283 static ssize_t gpio_keys_store_##name(struct device *dev,		\
284 				      struct device_attribute *attr,	\
285 				      const char *buf,			\
286 				      size_t count)			\
287 {									\
288 	struct platform_device *pdev = to_platform_device(dev);		\
289 	struct gpio_keys_drvdata *ddata = platform_get_drvdata(pdev);	\
290 	ssize_t error;							\
291 									\
292 	error = gpio_keys_attr_store_helper(ddata, buf, type);		\
293 	if (error)							\
294 		return error;						\
295 									\
296 	return count;							\
297 }
298 
299 ATTR_STORE_FN(disabled_keys, EV_KEY);
300 ATTR_STORE_FN(disabled_switches, EV_SW);
301 
302 /*
303  * ATTRIBUTES:
304  *
305  * /sys/devices/platform/gpio-keys/disabled_keys [rw]
306  * /sys/devices/platform/gpio-keys/disables_switches [rw]
307  */
308 static DEVICE_ATTR(disabled_keys, S_IWUSR | S_IRUGO,
309 		   gpio_keys_show_disabled_keys,
310 		   gpio_keys_store_disabled_keys);
311 static DEVICE_ATTR(disabled_switches, S_IWUSR | S_IRUGO,
312 		   gpio_keys_show_disabled_switches,
313 		   gpio_keys_store_disabled_switches);
314 
315 static struct attribute *gpio_keys_attrs[] = {
316 	&dev_attr_keys.attr,
317 	&dev_attr_switches.attr,
318 	&dev_attr_disabled_keys.attr,
319 	&dev_attr_disabled_switches.attr,
320 	NULL,
321 };
322 
323 static struct attribute_group gpio_keys_attr_group = {
324 	.attrs = gpio_keys_attrs,
325 };
326 
gpio_keys_gpio_report_event(struct gpio_button_data * bdata)327 static void gpio_keys_gpio_report_event(struct gpio_button_data *bdata)
328 {
329 	const struct gpio_keys_button *button = bdata->button;
330 	struct input_dev *input = bdata->input;
331 	unsigned int type = button->type ?: EV_KEY;
332 	int state = (gpio_get_value_cansleep(button->gpio) ? 1 : 0) ^ button->active_low;
333 
334 	if (type == EV_ABS) {
335 		if (state)
336 			input_event(input, type, button->code, button->value);
337 	} else {
338 		input_event(input, type, button->code, !!state);
339 	}
340 	input_sync(input);
341 }
342 
gpio_keys_gpio_work_func(struct work_struct * work)343 static void gpio_keys_gpio_work_func(struct work_struct *work)
344 {
345 	struct gpio_button_data *bdata =
346 		container_of(work, struct gpio_button_data, work);
347 
348 	gpio_keys_gpio_report_event(bdata);
349 }
350 
gpio_keys_gpio_timer(unsigned long _data)351 static void gpio_keys_gpio_timer(unsigned long _data)
352 {
353 	struct gpio_button_data *bdata = (struct gpio_button_data *)_data;
354 
355 	schedule_work(&bdata->work);
356 }
357 
gpio_keys_gpio_isr(int irq,void * dev_id)358 static irqreturn_t gpio_keys_gpio_isr(int irq, void *dev_id)
359 {
360 	struct gpio_button_data *bdata = dev_id;
361 
362 	BUG_ON(irq != bdata->irq);
363 
364 	if (bdata->timer_debounce)
365 		mod_timer(&bdata->timer,
366 			jiffies + msecs_to_jiffies(bdata->timer_debounce));
367 	else
368 		schedule_work(&bdata->work);
369 
370 	return IRQ_HANDLED;
371 }
372 
gpio_keys_irq_timer(unsigned long _data)373 static void gpio_keys_irq_timer(unsigned long _data)
374 {
375 	struct gpio_button_data *bdata = (struct gpio_button_data *)_data;
376 	struct input_dev *input = bdata->input;
377 	unsigned long flags;
378 
379 	spin_lock_irqsave(&bdata->lock, flags);
380 	if (bdata->key_pressed) {
381 		input_event(input, EV_KEY, bdata->button->code, 0);
382 		input_sync(input);
383 		bdata->key_pressed = false;
384 	}
385 	spin_unlock_irqrestore(&bdata->lock, flags);
386 }
387 
gpio_keys_irq_isr(int irq,void * dev_id)388 static irqreturn_t gpio_keys_irq_isr(int irq, void *dev_id)
389 {
390 	struct gpio_button_data *bdata = dev_id;
391 	const struct gpio_keys_button *button = bdata->button;
392 	struct input_dev *input = bdata->input;
393 	unsigned long flags;
394 
395 	BUG_ON(irq != bdata->irq);
396 
397 	spin_lock_irqsave(&bdata->lock, flags);
398 
399 	if (!bdata->key_pressed) {
400 		input_event(input, EV_KEY, button->code, 1);
401 		input_sync(input);
402 
403 		if (!bdata->timer_debounce) {
404 			input_event(input, EV_KEY, button->code, 0);
405 			input_sync(input);
406 			goto out;
407 		}
408 
409 		bdata->key_pressed = true;
410 	}
411 
412 	if (bdata->timer_debounce)
413 		mod_timer(&bdata->timer,
414 			jiffies + msecs_to_jiffies(bdata->timer_debounce));
415 out:
416 	spin_unlock_irqrestore(&bdata->lock, flags);
417 	return IRQ_HANDLED;
418 }
419 
gpio_keys_setup_key(struct platform_device * pdev,struct input_dev * input,struct gpio_button_data * bdata,const struct gpio_keys_button * button)420 static int __devinit gpio_keys_setup_key(struct platform_device *pdev,
421 					 struct input_dev *input,
422 					 struct gpio_button_data *bdata,
423 					 const struct gpio_keys_button *button)
424 {
425 	const char *desc = button->desc ? button->desc : "gpio_keys";
426 	struct device *dev = &pdev->dev;
427 	irq_handler_t isr;
428 	unsigned long irqflags;
429 	int irq, error;
430 
431 	bdata->input = input;
432 	bdata->button = button;
433 	spin_lock_init(&bdata->lock);
434 
435 	if (gpio_is_valid(button->gpio)) {
436 
437 		error = gpio_request(button->gpio, desc);
438 		if (error < 0) {
439 			dev_err(dev, "Failed to request GPIO %d, error %d\n",
440 				button->gpio, error);
441 			return error;
442 		}
443 
444 		error = gpio_direction_input(button->gpio);
445 		if (error < 0) {
446 			dev_err(dev,
447 				"Failed to configure direction for GPIO %d, error %d\n",
448 				button->gpio, error);
449 			goto fail;
450 		}
451 
452 		if (button->debounce_interval) {
453 			error = gpio_set_debounce(button->gpio,
454 					button->debounce_interval * 1000);
455 			/* use timer if gpiolib doesn't provide debounce */
456 			if (error < 0)
457 				bdata->timer_debounce =
458 						button->debounce_interval;
459 		}
460 
461 		irq = gpio_to_irq(button->gpio);
462 		if (irq < 0) {
463 			error = irq;
464 			dev_err(dev,
465 				"Unable to get irq number for GPIO %d, error %d\n",
466 				button->gpio, error);
467 			goto fail;
468 		}
469 		bdata->irq = irq;
470 
471 		INIT_WORK(&bdata->work, gpio_keys_gpio_work_func);
472 		setup_timer(&bdata->timer,
473 			    gpio_keys_gpio_timer, (unsigned long)bdata);
474 
475 		isr = gpio_keys_gpio_isr;
476 		irqflags = IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING;
477 
478 	} else {
479 		if (!button->irq) {
480 			dev_err(dev, "No IRQ specified\n");
481 			return -EINVAL;
482 		}
483 		bdata->irq = button->irq;
484 
485 		if (button->type && button->type != EV_KEY) {
486 			dev_err(dev, "Only EV_KEY allowed for IRQ buttons.\n");
487 			return -EINVAL;
488 		}
489 
490 		bdata->timer_debounce = button->debounce_interval;
491 		setup_timer(&bdata->timer,
492 			    gpio_keys_irq_timer, (unsigned long)bdata);
493 
494 		isr = gpio_keys_irq_isr;
495 		irqflags = 0;
496 	}
497 
498 	input_set_capability(input, button->type ?: EV_KEY, button->code);
499 
500 	/*
501 	 * If platform has specified that the button can be disabled,
502 	 * we don't want it to share the interrupt line.
503 	 */
504 	if (!button->can_disable)
505 		irqflags |= IRQF_SHARED;
506 
507 	error = request_any_context_irq(bdata->irq, isr, irqflags, desc, bdata);
508 	if (error < 0) {
509 		dev_err(dev, "Unable to claim irq %d; error %d\n",
510 			bdata->irq, error);
511 		goto fail;
512 	}
513 
514 	return 0;
515 
516 fail:
517 	if (gpio_is_valid(button->gpio))
518 		gpio_free(button->gpio);
519 
520 	return error;
521 }
522 
gpio_keys_open(struct input_dev * input)523 static int gpio_keys_open(struct input_dev *input)
524 {
525 	struct gpio_keys_drvdata *ddata = input_get_drvdata(input);
526 
527 	return ddata->enable ? ddata->enable(input->dev.parent) : 0;
528 }
529 
gpio_keys_close(struct input_dev * input)530 static void gpio_keys_close(struct input_dev *input)
531 {
532 	struct gpio_keys_drvdata *ddata = input_get_drvdata(input);
533 
534 	if (ddata->disable)
535 		ddata->disable(input->dev.parent);
536 }
537 
538 /*
539  * Handlers for alternative sources of platform_data
540  */
541 #ifdef CONFIG_OF
542 /*
543  * Translate OpenFirmware node properties into platform_data
544  */
gpio_keys_get_devtree_pdata(struct device * dev,struct gpio_keys_platform_data * pdata)545 static int gpio_keys_get_devtree_pdata(struct device *dev,
546 			    struct gpio_keys_platform_data *pdata)
547 {
548 	struct device_node *node, *pp;
549 	int i;
550 	struct gpio_keys_button *buttons;
551 	u32 reg;
552 
553 	node = dev->of_node;
554 	if (node == NULL)
555 		return -ENODEV;
556 
557 	memset(pdata, 0, sizeof *pdata);
558 
559 	pdata->rep = !!of_get_property(node, "autorepeat", NULL);
560 
561 	/* First count the subnodes */
562 	pdata->nbuttons = 0;
563 	pp = NULL;
564 	while ((pp = of_get_next_child(node, pp)))
565 		pdata->nbuttons++;
566 
567 	if (pdata->nbuttons == 0)
568 		return -ENODEV;
569 
570 	buttons = kzalloc(pdata->nbuttons * (sizeof *buttons), GFP_KERNEL);
571 	if (!buttons)
572 		return -ENOMEM;
573 
574 	pp = NULL;
575 	i = 0;
576 	while ((pp = of_get_next_child(node, pp))) {
577 		enum of_gpio_flags flags;
578 
579 		if (!of_find_property(pp, "gpios", NULL)) {
580 			pdata->nbuttons--;
581 			dev_warn(dev, "Found button without gpios\n");
582 			continue;
583 		}
584 		buttons[i].gpio = of_get_gpio_flags(pp, 0, &flags);
585 		buttons[i].active_low = flags & OF_GPIO_ACTIVE_LOW;
586 
587 		if (of_property_read_u32(pp, "linux,code", &reg)) {
588 			dev_err(dev, "Button without keycode: 0x%x\n", buttons[i].gpio);
589 			goto out_fail;
590 		}
591 		buttons[i].code = reg;
592 
593 		buttons[i].desc = of_get_property(pp, "label", NULL);
594 
595 		if (of_property_read_u32(pp, "linux,input-type", &reg) == 0)
596 			buttons[i].type = reg;
597 		else
598 			buttons[i].type = EV_KEY;
599 
600 		buttons[i].wakeup = !!of_get_property(pp, "gpio-key,wakeup", NULL);
601 
602 		if (of_property_read_u32(pp, "debounce-interval", &reg) == 0)
603 			buttons[i].debounce_interval = reg;
604 		else
605 			buttons[i].debounce_interval = 5;
606 
607 		i++;
608 	}
609 
610 	pdata->buttons = buttons;
611 
612 	return 0;
613 
614 out_fail:
615 	kfree(buttons);
616 	return -ENODEV;
617 }
618 
619 static struct of_device_id gpio_keys_of_match[] = {
620 	{ .compatible = "gpio-keys", },
621 	{ },
622 };
623 MODULE_DEVICE_TABLE(of, gpio_keys_of_match);
624 
625 #else
626 
gpio_keys_get_devtree_pdata(struct device * dev,struct gpio_keys_platform_data * altp)627 static int gpio_keys_get_devtree_pdata(struct device *dev,
628 			    struct gpio_keys_platform_data *altp)
629 {
630 	return -ENODEV;
631 }
632 
633 #define gpio_keys_of_match NULL
634 
635 #endif
636 
gpio_remove_key(struct gpio_button_data * bdata)637 static void gpio_remove_key(struct gpio_button_data *bdata)
638 {
639 	free_irq(bdata->irq, bdata);
640 	if (bdata->timer_debounce)
641 		del_timer_sync(&bdata->timer);
642 	cancel_work_sync(&bdata->work);
643 	if (gpio_is_valid(bdata->button->gpio))
644 		gpio_free(bdata->button->gpio);
645 }
646 
gpio_keys_probe(struct platform_device * pdev)647 static int __devinit gpio_keys_probe(struct platform_device *pdev)
648 {
649 	const struct gpio_keys_platform_data *pdata = pdev->dev.platform_data;
650 	struct gpio_keys_drvdata *ddata;
651 	struct device *dev = &pdev->dev;
652 	struct gpio_keys_platform_data alt_pdata;
653 	struct input_dev *input;
654 	int i, error;
655 	int wakeup = 0;
656 
657 	if (!pdata) {
658 		error = gpio_keys_get_devtree_pdata(dev, &alt_pdata);
659 		if (error)
660 			return error;
661 		pdata = &alt_pdata;
662 	}
663 
664 	ddata = kzalloc(sizeof(struct gpio_keys_drvdata) +
665 			pdata->nbuttons * sizeof(struct gpio_button_data),
666 			GFP_KERNEL);
667 	input = input_allocate_device();
668 	if (!ddata || !input) {
669 		dev_err(dev, "failed to allocate state\n");
670 		error = -ENOMEM;
671 		goto fail1;
672 	}
673 
674 	ddata->input = input;
675 	ddata->n_buttons = pdata->nbuttons;
676 	ddata->enable = pdata->enable;
677 	ddata->disable = pdata->disable;
678 	mutex_init(&ddata->disable_lock);
679 
680 	platform_set_drvdata(pdev, ddata);
681 	input_set_drvdata(input, ddata);
682 
683 	input->name = pdata->name ? : pdev->name;
684 	input->phys = "gpio-keys/input0";
685 	input->dev.parent = &pdev->dev;
686 	input->open = gpio_keys_open;
687 	input->close = gpio_keys_close;
688 
689 	input->id.bustype = BUS_HOST;
690 	input->id.vendor = 0x0001;
691 	input->id.product = 0x0001;
692 	input->id.version = 0x0100;
693 
694 	/* Enable auto repeat feature of Linux input subsystem */
695 	if (pdata->rep)
696 		__set_bit(EV_REP, input->evbit);
697 
698 	for (i = 0; i < pdata->nbuttons; i++) {
699 		const struct gpio_keys_button *button = &pdata->buttons[i];
700 		struct gpio_button_data *bdata = &ddata->data[i];
701 
702 		error = gpio_keys_setup_key(pdev, input, bdata, button);
703 		if (error)
704 			goto fail2;
705 
706 		if (button->wakeup)
707 			wakeup = 1;
708 	}
709 
710 	error = sysfs_create_group(&pdev->dev.kobj, &gpio_keys_attr_group);
711 	if (error) {
712 		dev_err(dev, "Unable to export keys/switches, error: %d\n",
713 			error);
714 		goto fail2;
715 	}
716 
717 	error = input_register_device(input);
718 	if (error) {
719 		dev_err(dev, "Unable to register input device, error: %d\n",
720 			error);
721 		goto fail3;
722 	}
723 
724 	/* get current state of buttons that are connected to GPIOs */
725 	for (i = 0; i < pdata->nbuttons; i++) {
726 		struct gpio_button_data *bdata = &ddata->data[i];
727 		if (gpio_is_valid(bdata->button->gpio))
728 			gpio_keys_gpio_report_event(bdata);
729 	}
730 	input_sync(input);
731 
732 	device_init_wakeup(&pdev->dev, wakeup);
733 
734 	return 0;
735 
736  fail3:
737 	sysfs_remove_group(&pdev->dev.kobj, &gpio_keys_attr_group);
738  fail2:
739 	while (--i >= 0)
740 		gpio_remove_key(&ddata->data[i]);
741 
742 	platform_set_drvdata(pdev, NULL);
743  fail1:
744 	input_free_device(input);
745 	kfree(ddata);
746 	/* If we have no platform_data, we allocated buttons dynamically. */
747 	if (!pdev->dev.platform_data)
748 		kfree(pdata->buttons);
749 
750 	return error;
751 }
752 
gpio_keys_remove(struct platform_device * pdev)753 static int __devexit gpio_keys_remove(struct platform_device *pdev)
754 {
755 	struct gpio_keys_drvdata *ddata = platform_get_drvdata(pdev);
756 	struct input_dev *input = ddata->input;
757 	int i;
758 
759 	sysfs_remove_group(&pdev->dev.kobj, &gpio_keys_attr_group);
760 
761 	device_init_wakeup(&pdev->dev, 0);
762 
763 	for (i = 0; i < ddata->n_buttons; i++)
764 		gpio_remove_key(&ddata->data[i]);
765 
766 	input_unregister_device(input);
767 
768 	/*
769 	 * If we had no platform_data, we allocated buttons dynamically, and
770 	 * must free them here. ddata->data[0].button is the pointer to the
771 	 * beginning of the allocated array.
772 	 */
773 	if (!pdev->dev.platform_data)
774 		kfree(ddata->data[0].button);
775 
776 	kfree(ddata);
777 
778 	return 0;
779 }
780 
781 #ifdef CONFIG_PM_SLEEP
gpio_keys_suspend(struct device * dev)782 static int gpio_keys_suspend(struct device *dev)
783 {
784 	struct gpio_keys_drvdata *ddata = dev_get_drvdata(dev);
785 	int i;
786 
787 	if (device_may_wakeup(dev)) {
788 		for (i = 0; i < ddata->n_buttons; i++) {
789 			struct gpio_button_data *bdata = &ddata->data[i];
790 			if (bdata->button->wakeup)
791 				enable_irq_wake(bdata->irq);
792 		}
793 	}
794 
795 	return 0;
796 }
797 
gpio_keys_resume(struct device * dev)798 static int gpio_keys_resume(struct device *dev)
799 {
800 	struct gpio_keys_drvdata *ddata = dev_get_drvdata(dev);
801 	int i;
802 
803 	for (i = 0; i < ddata->n_buttons; i++) {
804 		struct gpio_button_data *bdata = &ddata->data[i];
805 		if (bdata->button->wakeup && device_may_wakeup(dev))
806 			disable_irq_wake(bdata->irq);
807 
808 		if (gpio_is_valid(bdata->button->gpio))
809 			gpio_keys_gpio_report_event(bdata);
810 	}
811 	input_sync(ddata->input);
812 
813 	return 0;
814 }
815 #endif
816 
817 static SIMPLE_DEV_PM_OPS(gpio_keys_pm_ops, gpio_keys_suspend, gpio_keys_resume);
818 
819 static struct platform_driver gpio_keys_device_driver = {
820 	.probe		= gpio_keys_probe,
821 	.remove		= __devexit_p(gpio_keys_remove),
822 	.driver		= {
823 		.name	= "gpio-keys",
824 		.owner	= THIS_MODULE,
825 		.pm	= &gpio_keys_pm_ops,
826 		.of_match_table = gpio_keys_of_match,
827 	}
828 };
829 
gpio_keys_init(void)830 static int __init gpio_keys_init(void)
831 {
832 	return platform_driver_register(&gpio_keys_device_driver);
833 }
834 
gpio_keys_exit(void)835 static void __exit gpio_keys_exit(void)
836 {
837 	platform_driver_unregister(&gpio_keys_device_driver);
838 }
839 
840 late_initcall(gpio_keys_init);
841 module_exit(gpio_keys_exit);
842 
843 MODULE_LICENSE("GPL");
844 MODULE_AUTHOR("Phil Blundell <pb@handhelds.org>");
845 MODULE_DESCRIPTION("Keyboard driver for GPIOs");
846 MODULE_ALIAS("platform:gpio-keys");
847