1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Apple SoC pinctrl+GPIO+external IRQ driver
4 *
5 * Copyright (C) The Asahi Linux Contributors
6 * Copyright (C) 2020 Corellium LLC
7 *
8 * Based on: pinctrl-pistachio.c
9 * Copyright (C) 2014 Imagination Technologies Ltd.
10 * Copyright (C) 2014 Google, Inc.
11 */
12
13 #include <dt-bindings/pinctrl/apple.h>
14 #include <linux/bits.h>
15 #include <linux/gpio/driver.h>
16 #include <linux/interrupt.h>
17 #include <linux/irq.h>
18 #include <linux/module.h>
19 #include <linux/of.h>
20 #include <linux/of_irq.h>
21 #include <linux/pinctrl/pinctrl.h>
22 #include <linux/pinctrl/pinmux.h>
23 #include <linux/platform_device.h>
24 #include <linux/regmap.h>
25
26 #include "pinctrl-utils.h"
27 #include "core.h"
28 #include "pinmux.h"
29
30 struct apple_gpio_pinctrl {
31 struct device *dev;
32 struct pinctrl_dev *pctldev;
33
34 void __iomem *base;
35 struct regmap *map;
36
37 struct pinctrl_desc pinctrl_desc;
38 struct gpio_chip gpio_chip;
39 u8 irqgrps[];
40 };
41
42 #define REG_GPIO(x) (4 * (x))
43 #define REG_GPIOx_DATA BIT(0)
44 #define REG_GPIOx_MODE GENMASK(3, 1)
45 #define REG_GPIOx_OUT 1
46 #define REG_GPIOx_IN_IRQ_HI 2
47 #define REG_GPIOx_IN_IRQ_LO 3
48 #define REG_GPIOx_IN_IRQ_UP 4
49 #define REG_GPIOx_IN_IRQ_DN 5
50 #define REG_GPIOx_IN_IRQ_ANY 6
51 #define REG_GPIOx_IN_IRQ_OFF 7
52 #define REG_GPIOx_PERIPH GENMASK(6, 5)
53 #define REG_GPIOx_PULL GENMASK(8, 7)
54 #define REG_GPIOx_PULL_OFF 0
55 #define REG_GPIOx_PULL_DOWN 1
56 #define REG_GPIOx_PULL_UP_STRONG 2
57 #define REG_GPIOx_PULL_UP 3
58 #define REG_GPIOx_INPUT_ENABLE BIT(9)
59 #define REG_GPIOx_DRIVE_STRENGTH0 GENMASK(11, 10)
60 #define REG_GPIOx_SCHMITT BIT(15)
61 #define REG_GPIOx_GRP GENMASK(18, 16)
62 #define REG_GPIOx_LOCK BIT(21)
63 #define REG_GPIOx_DRIVE_STRENGTH1 GENMASK(23, 22)
64 #define REG_IRQ(g, x) (0x800 + 0x40 * (g) + 4 * ((x) >> 5))
65
66 struct regmap_config regmap_config = {
67 .reg_bits = 32,
68 .val_bits = 32,
69 .reg_stride = 4,
70 .cache_type = REGCACHE_FLAT,
71 .max_register = 512 * sizeof(u32),
72 .num_reg_defaults_raw = 512,
73 .use_relaxed_mmio = true,
74 .use_raw_spinlock = true,
75 };
76
77 /* No locking needed to mask/unmask IRQs as the interrupt mode is per pin-register. */
apple_gpio_set_reg(struct apple_gpio_pinctrl * pctl,unsigned int pin,u32 mask,u32 value)78 static void apple_gpio_set_reg(struct apple_gpio_pinctrl *pctl,
79 unsigned int pin, u32 mask, u32 value)
80 {
81 regmap_update_bits(pctl->map, REG_GPIO(pin), mask, value);
82 }
83
apple_gpio_get_reg(struct apple_gpio_pinctrl * pctl,unsigned int pin)84 static u32 apple_gpio_get_reg(struct apple_gpio_pinctrl *pctl,
85 unsigned int pin)
86 {
87 int ret;
88 u32 val;
89
90 ret = regmap_read(pctl->map, REG_GPIO(pin), &val);
91 if (ret)
92 return 0;
93
94 return val;
95 }
96
97 /* Pin controller functions */
98
apple_gpio_dt_node_to_map(struct pinctrl_dev * pctldev,struct device_node * node,struct pinctrl_map ** map,unsigned * num_maps)99 static int apple_gpio_dt_node_to_map(struct pinctrl_dev *pctldev,
100 struct device_node *node,
101 struct pinctrl_map **map,
102 unsigned *num_maps)
103 {
104 unsigned reserved_maps;
105 struct apple_gpio_pinctrl *pctl;
106 u32 pinfunc, pin, func;
107 int num_pins, i, ret;
108 const char *group_name;
109 const char *function_name;
110
111 *map = NULL;
112 *num_maps = 0;
113 reserved_maps = 0;
114
115 pctl = pinctrl_dev_get_drvdata(pctldev);
116
117 ret = of_property_count_u32_elems(node, "pinmux");
118 if (ret <= 0) {
119 dev_err(pctl->dev,
120 "missing or empty pinmux property in node %pOFn.\n",
121 node);
122 return ret ? ret : -EINVAL;
123 }
124
125 num_pins = ret;
126
127 ret = pinctrl_utils_reserve_map(pctldev, map, &reserved_maps, num_maps, num_pins);
128 if (ret)
129 return ret;
130
131 for (i = 0; i < num_pins; i++) {
132 ret = of_property_read_u32_index(node, "pinmux", i, &pinfunc);
133 if (ret)
134 goto free_map;
135
136 pin = APPLE_PIN(pinfunc);
137 func = APPLE_FUNC(pinfunc);
138
139 if (func >= pinmux_generic_get_function_count(pctldev)) {
140 ret = -EINVAL;
141 goto free_map;
142 }
143
144 group_name = pinctrl_generic_get_group_name(pctldev, pin);
145 function_name = pinmux_generic_get_function_name(pctl->pctldev, func);
146 ret = pinctrl_utils_add_map_mux(pctl->pctldev, map,
147 &reserved_maps, num_maps,
148 group_name, function_name);
149 if (ret)
150 goto free_map;
151 }
152
153 free_map:
154 if (ret < 0)
155 pinctrl_utils_free_map(pctldev, *map, *num_maps);
156
157 return ret;
158 }
159
160 static const struct pinctrl_ops apple_gpio_pinctrl_ops = {
161 .get_groups_count = pinctrl_generic_get_group_count,
162 .get_group_name = pinctrl_generic_get_group_name,
163 .get_group_pins = pinctrl_generic_get_group_pins,
164 .dt_node_to_map = apple_gpio_dt_node_to_map,
165 .dt_free_map = pinctrl_utils_free_map,
166 };
167
168 /* Pin multiplexer functions */
169
apple_gpio_pinmux_set(struct pinctrl_dev * pctldev,unsigned func,unsigned group)170 static int apple_gpio_pinmux_set(struct pinctrl_dev *pctldev, unsigned func,
171 unsigned group)
172 {
173 struct apple_gpio_pinctrl *pctl = pinctrl_dev_get_drvdata(pctldev);
174
175 apple_gpio_set_reg(
176 pctl, group, REG_GPIOx_PERIPH | REG_GPIOx_INPUT_ENABLE,
177 FIELD_PREP(REG_GPIOx_PERIPH, func) | REG_GPIOx_INPUT_ENABLE);
178
179 return 0;
180 }
181
182 static const struct pinmux_ops apple_gpio_pinmux_ops = {
183 .get_functions_count = pinmux_generic_get_function_count,
184 .get_function_name = pinmux_generic_get_function_name,
185 .get_function_groups = pinmux_generic_get_function_groups,
186 .set_mux = apple_gpio_pinmux_set,
187 .strict = true,
188 };
189
190 /* GPIO chip functions */
191
apple_gpio_get_direction(struct gpio_chip * chip,unsigned int offset)192 static int apple_gpio_get_direction(struct gpio_chip *chip, unsigned int offset)
193 {
194 struct apple_gpio_pinctrl *pctl = gpiochip_get_data(chip);
195 unsigned int reg = apple_gpio_get_reg(pctl, offset);
196
197 if (FIELD_GET(REG_GPIOx_MODE, reg) == REG_GPIOx_OUT)
198 return GPIO_LINE_DIRECTION_OUT;
199 return GPIO_LINE_DIRECTION_IN;
200 }
201
apple_gpio_get(struct gpio_chip * chip,unsigned offset)202 static int apple_gpio_get(struct gpio_chip *chip, unsigned offset)
203 {
204 struct apple_gpio_pinctrl *pctl = gpiochip_get_data(chip);
205 unsigned int reg = apple_gpio_get_reg(pctl, offset);
206
207 /*
208 * If this is an input GPIO, read the actual value (not the
209 * cached regmap value)
210 */
211 if (FIELD_GET(REG_GPIOx_MODE, reg) != REG_GPIOx_OUT)
212 reg = readl_relaxed(pctl->base + REG_GPIO(offset));
213
214 return !!(reg & REG_GPIOx_DATA);
215 }
216
apple_gpio_set(struct gpio_chip * chip,unsigned int offset,int value)217 static void apple_gpio_set(struct gpio_chip *chip, unsigned int offset, int value)
218 {
219 struct apple_gpio_pinctrl *pctl = gpiochip_get_data(chip);
220
221 apple_gpio_set_reg(pctl, offset, REG_GPIOx_DATA, value ? REG_GPIOx_DATA : 0);
222 }
223
apple_gpio_direction_input(struct gpio_chip * chip,unsigned int offset)224 static int apple_gpio_direction_input(struct gpio_chip *chip, unsigned int offset)
225 {
226 struct apple_gpio_pinctrl *pctl = gpiochip_get_data(chip);
227
228 apple_gpio_set_reg(pctl, offset,
229 REG_GPIOx_PERIPH | REG_GPIOx_MODE | REG_GPIOx_DATA |
230 REG_GPIOx_INPUT_ENABLE,
231 FIELD_PREP(REG_GPIOx_MODE, REG_GPIOx_IN_IRQ_OFF) |
232 REG_GPIOx_INPUT_ENABLE);
233 return 0;
234 }
235
apple_gpio_direction_output(struct gpio_chip * chip,unsigned int offset,int value)236 static int apple_gpio_direction_output(struct gpio_chip *chip,
237 unsigned int offset, int value)
238 {
239 struct apple_gpio_pinctrl *pctl = gpiochip_get_data(chip);
240
241 apple_gpio_set_reg(pctl, offset,
242 REG_GPIOx_PERIPH | REG_GPIOx_MODE | REG_GPIOx_DATA,
243 FIELD_PREP(REG_GPIOx_MODE, REG_GPIOx_OUT) |
244 (value ? REG_GPIOx_DATA : 0));
245 return 0;
246 }
247
248 /* IRQ chip functions */
249
apple_gpio_irq_ack(struct irq_data * data)250 static void apple_gpio_irq_ack(struct irq_data *data)
251 {
252 struct apple_gpio_pinctrl *pctl = gpiochip_get_data(irq_data_get_irq_chip_data(data));
253 unsigned int irqgrp = FIELD_GET(REG_GPIOx_GRP, apple_gpio_get_reg(pctl, data->hwirq));
254
255 writel(BIT(data->hwirq % 32), pctl->base + REG_IRQ(irqgrp, data->hwirq));
256 }
257
apple_gpio_irq_type(unsigned int type)258 static unsigned int apple_gpio_irq_type(unsigned int type)
259 {
260 switch (type & IRQ_TYPE_SENSE_MASK) {
261 case IRQ_TYPE_EDGE_RISING:
262 return REG_GPIOx_IN_IRQ_UP;
263 case IRQ_TYPE_EDGE_FALLING:
264 return REG_GPIOx_IN_IRQ_DN;
265 case IRQ_TYPE_EDGE_BOTH:
266 return REG_GPIOx_IN_IRQ_ANY;
267 case IRQ_TYPE_LEVEL_HIGH:
268 return REG_GPIOx_IN_IRQ_HI;
269 case IRQ_TYPE_LEVEL_LOW:
270 return REG_GPIOx_IN_IRQ_LO;
271 default:
272 return REG_GPIOx_IN_IRQ_OFF;
273 }
274 }
275
apple_gpio_irq_mask(struct irq_data * data)276 static void apple_gpio_irq_mask(struct irq_data *data)
277 {
278 struct gpio_chip *gc = irq_data_get_irq_chip_data(data);
279 struct apple_gpio_pinctrl *pctl = gpiochip_get_data(gc);
280
281 apple_gpio_set_reg(pctl, data->hwirq, REG_GPIOx_MODE,
282 FIELD_PREP(REG_GPIOx_MODE, REG_GPIOx_IN_IRQ_OFF));
283 gpiochip_disable_irq(gc, data->hwirq);
284 }
285
apple_gpio_irq_unmask(struct irq_data * data)286 static void apple_gpio_irq_unmask(struct irq_data *data)
287 {
288 struct gpio_chip *gc = irq_data_get_irq_chip_data(data);
289 struct apple_gpio_pinctrl *pctl = gpiochip_get_data(gc);
290 unsigned int irqtype = apple_gpio_irq_type(irqd_get_trigger_type(data));
291
292 gpiochip_enable_irq(gc, data->hwirq);
293 apple_gpio_set_reg(pctl, data->hwirq, REG_GPIOx_MODE,
294 FIELD_PREP(REG_GPIOx_MODE, irqtype));
295 }
296
apple_gpio_irq_startup(struct irq_data * data)297 static unsigned int apple_gpio_irq_startup(struct irq_data *data)
298 {
299 struct gpio_chip *chip = irq_data_get_irq_chip_data(data);
300 struct apple_gpio_pinctrl *pctl = gpiochip_get_data(chip);
301
302 apple_gpio_set_reg(pctl, data->hwirq, REG_GPIOx_GRP,
303 FIELD_PREP(REG_GPIOx_GRP, 0));
304
305 apple_gpio_direction_input(chip, data->hwirq);
306 apple_gpio_irq_unmask(data);
307
308 return 0;
309 }
310
apple_gpio_irq_set_type(struct irq_data * data,unsigned int type)311 static int apple_gpio_irq_set_type(struct irq_data *data, unsigned int type)
312 {
313 struct apple_gpio_pinctrl *pctl = gpiochip_get_data(irq_data_get_irq_chip_data(data));
314 unsigned int irqtype = apple_gpio_irq_type(type);
315
316 if (irqtype == REG_GPIOx_IN_IRQ_OFF)
317 return -EINVAL;
318
319 apple_gpio_set_reg(pctl, data->hwirq, REG_GPIOx_MODE,
320 FIELD_PREP(REG_GPIOx_MODE, irqtype));
321
322 if (type & IRQ_TYPE_LEVEL_MASK)
323 irq_set_handler_locked(data, handle_level_irq);
324 else
325 irq_set_handler_locked(data, handle_edge_irq);
326 return 0;
327 }
328
apple_gpio_irq_handler(struct irq_desc * desc)329 static void apple_gpio_irq_handler(struct irq_desc *desc)
330 {
331 struct irq_chip *chip = irq_desc_get_chip(desc);
332 u8 *grpp = irq_desc_get_handler_data(desc);
333 struct apple_gpio_pinctrl *pctl;
334 unsigned int pinh, pinl;
335 unsigned long pending;
336 struct gpio_chip *gc;
337
338 pctl = container_of(grpp - *grpp, typeof(*pctl), irqgrps[0]);
339 gc = &pctl->gpio_chip;
340
341 chained_irq_enter(chip, desc);
342 for (pinh = 0; pinh < gc->ngpio; pinh += 32) {
343 pending = readl_relaxed(pctl->base + REG_IRQ(*grpp, pinh));
344 for_each_set_bit(pinl, &pending, 32)
345 generic_handle_domain_irq(gc->irq.domain, pinh + pinl);
346 }
347 chained_irq_exit(chip, desc);
348 }
349
350 static const struct irq_chip apple_gpio_irqchip = {
351 .name = "Apple-GPIO",
352 .irq_startup = apple_gpio_irq_startup,
353 .irq_ack = apple_gpio_irq_ack,
354 .irq_mask = apple_gpio_irq_mask,
355 .irq_unmask = apple_gpio_irq_unmask,
356 .irq_set_type = apple_gpio_irq_set_type,
357 .flags = IRQCHIP_IMMUTABLE,
358 GPIOCHIP_IRQ_RESOURCE_HELPERS,
359 };
360
361 /* Probe & register */
362
apple_gpio_register(struct apple_gpio_pinctrl * pctl)363 static int apple_gpio_register(struct apple_gpio_pinctrl *pctl)
364 {
365 struct gpio_irq_chip *girq = &pctl->gpio_chip.irq;
366 void **irq_data = NULL;
367 int ret;
368
369 pctl->gpio_chip.label = dev_name(pctl->dev);
370 pctl->gpio_chip.request = gpiochip_generic_request;
371 pctl->gpio_chip.free = gpiochip_generic_free;
372 pctl->gpio_chip.get_direction = apple_gpio_get_direction;
373 pctl->gpio_chip.direction_input = apple_gpio_direction_input;
374 pctl->gpio_chip.direction_output = apple_gpio_direction_output;
375 pctl->gpio_chip.get = apple_gpio_get;
376 pctl->gpio_chip.set = apple_gpio_set;
377 pctl->gpio_chip.base = -1;
378 pctl->gpio_chip.ngpio = pctl->pinctrl_desc.npins;
379 pctl->gpio_chip.parent = pctl->dev;
380
381 if (girq->num_parents) {
382 int i;
383
384 gpio_irq_chip_set_chip(girq, &apple_gpio_irqchip);
385 girq->parent_handler = apple_gpio_irq_handler;
386
387 girq->parents = kmalloc_array(girq->num_parents,
388 sizeof(*girq->parents),
389 GFP_KERNEL);
390 irq_data = kmalloc_array(girq->num_parents, sizeof(*irq_data),
391 GFP_KERNEL);
392 if (!girq->parents || !irq_data) {
393 ret = -ENOMEM;
394 goto out_free_irq_data;
395 }
396
397 for (i = 0; i < girq->num_parents; i++) {
398 ret = platform_get_irq(to_platform_device(pctl->dev), i);
399 if (ret < 0)
400 goto out_free_irq_data;
401
402 girq->parents[i] = ret;
403 pctl->irqgrps[i] = i;
404 irq_data[i] = &pctl->irqgrps[i];
405 }
406
407 girq->parent_handler_data_array = irq_data;
408 girq->per_parent_data = true;
409 girq->default_type = IRQ_TYPE_NONE;
410 girq->handler = handle_level_irq;
411 }
412
413 ret = devm_gpiochip_add_data(pctl->dev, &pctl->gpio_chip, pctl);
414
415 out_free_irq_data:
416 kfree(girq->parents);
417 kfree(irq_data);
418
419 return ret;
420 }
421
apple_gpio_pinctrl_probe(struct platform_device * pdev)422 static int apple_gpio_pinctrl_probe(struct platform_device *pdev)
423 {
424 struct apple_gpio_pinctrl *pctl;
425 struct pinctrl_pin_desc *pins;
426 unsigned int npins;
427 const char **pin_names;
428 unsigned int *pin_nums;
429 static const char* pinmux_functions[] = {
430 "gpio", "periph1", "periph2", "periph3"
431 };
432 unsigned int i, nirqs = 0;
433 int res;
434
435 if (of_property_read_bool(pdev->dev.of_node, "interrupt-controller")) {
436 res = platform_irq_count(pdev);
437 if (res > 0)
438 nirqs = res;
439 }
440
441 pctl = devm_kzalloc(&pdev->dev, struct_size(pctl, irqgrps, nirqs),
442 GFP_KERNEL);
443 if (!pctl)
444 return -ENOMEM;
445 pctl->dev = &pdev->dev;
446 pctl->gpio_chip.irq.num_parents = nirqs;
447 dev_set_drvdata(&pdev->dev, pctl);
448
449 if (of_property_read_u32(pdev->dev.of_node, "apple,npins", &npins))
450 return dev_err_probe(&pdev->dev, -EINVAL,
451 "apple,npins property not found\n");
452
453 pins = devm_kmalloc_array(&pdev->dev, npins, sizeof(pins[0]),
454 GFP_KERNEL);
455 pin_names = devm_kmalloc_array(&pdev->dev, npins, sizeof(pin_names[0]),
456 GFP_KERNEL);
457 pin_nums = devm_kmalloc_array(&pdev->dev, npins, sizeof(pin_nums[0]),
458 GFP_KERNEL);
459 if (!pins || !pin_names || !pin_nums)
460 return -ENOMEM;
461
462 pctl->base = devm_platform_ioremap_resource(pdev, 0);
463 if (IS_ERR(pctl->base))
464 return PTR_ERR(pctl->base);
465
466 pctl->map = devm_regmap_init_mmio(&pdev->dev, pctl->base, ®map_config);
467 if (IS_ERR(pctl->map))
468 return dev_err_probe(&pdev->dev, PTR_ERR(pctl->map),
469 "Failed to create regmap\n");
470
471 for (i = 0; i < npins; i++) {
472 pins[i].number = i;
473 pins[i].name = devm_kasprintf(&pdev->dev, GFP_KERNEL, "PIN%u", i);
474 pins[i].drv_data = pctl;
475 pin_names[i] = pins[i].name;
476 pin_nums[i] = i;
477 }
478
479 pctl->pinctrl_desc.name = dev_name(pctl->dev);
480 pctl->pinctrl_desc.pins = pins;
481 pctl->pinctrl_desc.npins = npins;
482 pctl->pinctrl_desc.pctlops = &apple_gpio_pinctrl_ops;
483 pctl->pinctrl_desc.pmxops = &apple_gpio_pinmux_ops;
484
485 pctl->pctldev = devm_pinctrl_register(&pdev->dev, &pctl->pinctrl_desc, pctl);
486 if (IS_ERR(pctl->pctldev))
487 return dev_err_probe(&pdev->dev, PTR_ERR(pctl->pctldev),
488 "Failed to register pinctrl device.\n");
489
490 for (i = 0; i < npins; i++) {
491 res = pinctrl_generic_add_group(pctl->pctldev, pins[i].name,
492 pin_nums + i, 1, pctl);
493 if (res < 0)
494 return dev_err_probe(pctl->dev, res,
495 "Failed to register group");
496 }
497
498 for (i = 0; i < ARRAY_SIZE(pinmux_functions); ++i) {
499 res = pinmux_generic_add_function(pctl->pctldev, pinmux_functions[i],
500 pin_names, npins, pctl);
501 if (res < 0)
502 return dev_err_probe(pctl->dev, res,
503 "Failed to register function.");
504 }
505
506 return apple_gpio_register(pctl);
507 }
508
509 static const struct of_device_id apple_gpio_pinctrl_of_match[] = {
510 { .compatible = "apple,pinctrl", },
511 { }
512 };
513 MODULE_DEVICE_TABLE(of, apple_gpio_pinctrl_of_match);
514
515 static struct platform_driver apple_gpio_pinctrl_driver = {
516 .driver = {
517 .name = "apple-gpio-pinctrl",
518 .of_match_table = apple_gpio_pinctrl_of_match,
519 .suppress_bind_attrs = true,
520 },
521 .probe = apple_gpio_pinctrl_probe,
522 };
523 module_platform_driver(apple_gpio_pinctrl_driver);
524
525 MODULE_DESCRIPTION("Apple pinctrl/GPIO driver");
526 MODULE_AUTHOR("Stan Skowronek <stan@corellium.com>");
527 MODULE_AUTHOR("Joey Gouly <joey.gouly@arm.com>");
528 MODULE_LICENSE("GPL v2");
529