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1/*
2 * ACPI helpers for GPIO API
3 *
4 * Copyright (C) 2012, Intel Corporation
5 * Authors: Mathias Nyman <mathias.nyman@linux.intel.com>
6 * Mika Westerberg <mika.westerberg@linux.intel.com>
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License version 2 as
10 * published by the Free Software Foundation.
11 */
12
13#include <linux/errno.h>
14#include <linux/gpio/consumer.h>
15#include <linux/gpio/driver.h>
16#include <linux/export.h>
17#include <linux/acpi.h>
18#include <linux/interrupt.h>
19#include <linux/mutex.h>
20
21#include "gpiolib.h"
22
23struct acpi_gpio_event {
24 struct list_head node;
25 acpi_handle handle;
26 unsigned int pin;
27 unsigned int irq;
28};
29
30struct acpi_gpio_connection {
31 struct list_head node;
32 struct gpio_desc *desc;
33};
34
35struct acpi_gpio_chip {
36 /*
37 * ACPICA requires that the first field of the context parameter
38 * passed to acpi_install_address_space_handler() is large enough
39 * to hold struct acpi_connection_info.
40 */
41 struct acpi_connection_info conn_info;
42 struct list_head conns;
43 struct mutex conn_lock;
44 struct gpio_chip *chip;
45 struct list_head events;
46};
47
48static int acpi_gpiochip_find(struct gpio_chip *gc, void *data)
49{
50 if (!gc->dev)
51 return false;
52
53 return ACPI_HANDLE(gc->dev) == data;
54}
55
56/**
57 * acpi_get_gpiod() - Translate ACPI GPIO pin to GPIO descriptor usable with GPIO API
58 * @path: ACPI GPIO controller full path name, (e.g. "\\_SB.GPO1")
59 * @pin: ACPI GPIO pin number (0-based, controller-relative)
60 *
61 * Returns GPIO descriptor to use with Linux generic GPIO API, or ERR_PTR
62 * error value
63 */
64
65static struct gpio_desc *acpi_get_gpiod(char *path, int pin)
66{
67 struct gpio_chip *chip;
68 acpi_handle handle;
69 acpi_status status;
70
71 status = acpi_get_handle(NULL, path, &handle);
72 if (ACPI_FAILURE(status))
73 return ERR_PTR(-ENODEV);
74
75 chip = gpiochip_find(handle, acpi_gpiochip_find);
76 if (!chip)
77 return ERR_PTR(-ENODEV);
78
79 if (pin < 0 || pin > chip->ngpio)
80 return ERR_PTR(-EINVAL);
81
82 return gpiochip_get_desc(chip, pin);
83}
84
85static irqreturn_t acpi_gpio_irq_handler(int irq, void *data)
86{
87 struct acpi_gpio_event *event = data;
88
89 acpi_evaluate_object(event->handle, NULL, NULL, NULL);
90
91 return IRQ_HANDLED;
92}
93
94static irqreturn_t acpi_gpio_irq_handler_evt(int irq, void *data)
95{
96 struct acpi_gpio_event *event = data;
97
98 acpi_execute_simple_method(event->handle, NULL, event->pin);
99
100 return IRQ_HANDLED;
101}
102
103static void acpi_gpio_chip_dh(acpi_handle handle, void *data)
104{
105 /* The address of this function is used as a key. */
106}
107
108static acpi_status acpi_gpiochip_request_interrupt(struct acpi_resource *ares,
109 void *context)
110{
111 struct acpi_gpio_chip *acpi_gpio = context;
112 struct gpio_chip *chip = acpi_gpio->chip;
113 struct acpi_resource_gpio *agpio;
114 acpi_handle handle, evt_handle;
115 struct acpi_gpio_event *event;
116 irq_handler_t handler = NULL;
117 struct gpio_desc *desc;
118 unsigned long irqflags;
119 int ret, pin, irq;
120
121 if (ares->type != ACPI_RESOURCE_TYPE_GPIO)
122 return AE_OK;
123
124 agpio = &ares->data.gpio;
125 if (agpio->connection_type != ACPI_RESOURCE_GPIO_TYPE_INT)
126 return AE_OK;
127
128 handle = ACPI_HANDLE(chip->dev);
129 pin = agpio->pin_table[0];
130
131 if (pin <= 255) {
132 char ev_name[5];
133 sprintf(ev_name, "_%c%02X",
134 agpio->triggering == ACPI_EDGE_SENSITIVE ? 'E' : 'L',
135 pin);
136 if (ACPI_SUCCESS(acpi_get_handle(handle, ev_name, &evt_handle)))
137 handler = acpi_gpio_irq_handler;
138 }
139 if (!handler) {
140 if (ACPI_SUCCESS(acpi_get_handle(handle, "_EVT", &evt_handle)))
141 handler = acpi_gpio_irq_handler_evt;
142 }
143 if (!handler)
144 return AE_BAD_PARAMETER;
145
146 desc = gpiochip_get_desc(chip, pin);
147 if (IS_ERR(desc)) {
148 dev_err(chip->dev, "Failed to get GPIO descriptor\n");
149 return AE_ERROR;
150 }
151
152 ret = gpiochip_request_own_desc(desc, "ACPI:Event");
153 if (ret) {
154 dev_err(chip->dev, "Failed to request GPIO\n");
155 return AE_ERROR;
156 }
157
158 gpiod_direction_input(desc);
159
160 ret = gpiod_lock_as_irq(desc);
161 if (ret) {
162 dev_err(chip->dev, "Failed to lock GPIO as interrupt\n");
163 goto fail_free_desc;
164 }
165
166 irq = gpiod_to_irq(desc);
167 if (irq < 0) {
168 dev_err(chip->dev, "Failed to translate GPIO to IRQ\n");
169 goto fail_unlock_irq;
170 }
171
172 irqflags = IRQF_ONESHOT;
173 if (agpio->triggering == ACPI_LEVEL_SENSITIVE) {
174 if (agpio->polarity == ACPI_ACTIVE_HIGH)
175 irqflags |= IRQF_TRIGGER_HIGH;
176 else
177 irqflags |= IRQF_TRIGGER_LOW;
178 } else {
179 switch (agpio->polarity) {
180 case ACPI_ACTIVE_HIGH:
181 irqflags |= IRQF_TRIGGER_RISING;
182 break;
183 case ACPI_ACTIVE_LOW:
184 irqflags |= IRQF_TRIGGER_FALLING;
185 break;
186 default:
187 irqflags |= IRQF_TRIGGER_RISING |
188 IRQF_TRIGGER_FALLING;
189 break;
190 }
191 }
192
193 event = kzalloc(sizeof(*event), GFP_KERNEL);
194 if (!event)
195 goto fail_unlock_irq;
196
197 event->handle = evt_handle;
198 event->irq = irq;
199 event->pin = pin;
200
201 ret = request_threaded_irq(event->irq, NULL, handler, irqflags,
202 "ACPI:Event", event);
203 if (ret) {
204 dev_err(chip->dev, "Failed to setup interrupt handler for %d\n",
205 event->irq);
206 goto fail_free_event;
207 }
208
209 list_add_tail(&event->node, &acpi_gpio->events);
210 return AE_OK;
211
212fail_free_event:
213 kfree(event);
214fail_unlock_irq:
215 gpiod_unlock_as_irq(desc);
216fail_free_desc:
217 gpiochip_free_own_desc(desc);
218
219 return AE_ERROR;
220}
221
222/**
223 * acpi_gpiochip_request_interrupts() - Register isr for gpio chip ACPI events
224 * @acpi_gpio: ACPI GPIO chip
225 *
226 * ACPI5 platforms can use GPIO signaled ACPI events. These GPIO interrupts are
227 * handled by ACPI event methods which need to be called from the GPIO
228 * chip's interrupt handler. acpi_gpiochip_request_interrupts finds out which
229 * gpio pins have acpi event methods and assigns interrupt handlers that calls
230 * the acpi event methods for those pins.
231 */
232static void acpi_gpiochip_request_interrupts(struct acpi_gpio_chip *acpi_gpio)
233{
234 struct gpio_chip *chip = acpi_gpio->chip;
235
236 if (!chip->to_irq)
237 return;
238
239 INIT_LIST_HEAD(&acpi_gpio->events);
240 acpi_walk_resources(ACPI_HANDLE(chip->dev), "_AEI",
241 acpi_gpiochip_request_interrupt, acpi_gpio);
242}
243
244/**
245 * acpi_gpiochip_free_interrupts() - Free GPIO ACPI event interrupts.
246 * @acpi_gpio: ACPI GPIO chip
247 *
248 * Free interrupts associated with GPIO ACPI event method for the given
249 * GPIO chip.
250 */
251static void acpi_gpiochip_free_interrupts(struct acpi_gpio_chip *acpi_gpio)
252{
253 struct acpi_gpio_event *event, *ep;
254 struct gpio_chip *chip = acpi_gpio->chip;
255
256 if (!chip->to_irq)
257 return;
258
259 list_for_each_entry_safe_reverse(event, ep, &acpi_gpio->events, node) {
260 struct gpio_desc *desc;
261
262 free_irq(event->irq, event);
263 desc = gpiochip_get_desc(chip, event->pin);
264 if (WARN_ON(IS_ERR(desc)))
265 continue;
266 gpiod_unlock_as_irq(desc);
267 gpiochip_free_own_desc(desc);
268 list_del(&event->node);
269 kfree(event);
270 }
271}
272
273struct acpi_gpio_lookup {
274 struct acpi_gpio_info info;
275 int index;
276 struct gpio_desc *desc;
277 int n;
278};
279
280static int acpi_find_gpio(struct acpi_resource *ares, void *data)
281{
282 struct acpi_gpio_lookup *lookup = data;
283
284 if (ares->type != ACPI_RESOURCE_TYPE_GPIO)
285 return 1;
286
287 if (lookup->n++ == lookup->index && !lookup->desc) {
288 const struct acpi_resource_gpio *agpio = &ares->data.gpio;
289
290 lookup->desc = acpi_get_gpiod(agpio->resource_source.string_ptr,
291 agpio->pin_table[0]);
292 lookup->info.gpioint =
293 agpio->connection_type == ACPI_RESOURCE_GPIO_TYPE_INT;
294 lookup->info.active_low =
295 agpio->polarity == ACPI_ACTIVE_LOW;
296 }
297
298 return 1;
299}
300
301/**
302 * acpi_get_gpiod_by_index() - get a GPIO descriptor from device resources
303 * @dev: pointer to a device to get GPIO from
304 * @index: index of GpioIo/GpioInt resource (starting from %0)
305 * @info: info pointer to fill in (optional)
306 *
307 * Function goes through ACPI resources for @dev and based on @index looks
308 * up a GpioIo/GpioInt resource, translates it to the Linux GPIO descriptor,
309 * and returns it. @index matches GpioIo/GpioInt resources only so if there
310 * are total %3 GPIO resources, the index goes from %0 to %2.
311 *
312 * If the GPIO cannot be translated or there is an error an ERR_PTR is
313 * returned.
314 *
315 * Note: if the GPIO resource has multiple entries in the pin list, this
316 * function only returns the first.
317 */
318struct gpio_desc *acpi_get_gpiod_by_index(struct device *dev, int index,
319 struct acpi_gpio_info *info)
320{
321 struct acpi_gpio_lookup lookup;
322 struct list_head resource_list;
323 struct acpi_device *adev;
324 acpi_handle handle;
325 int ret;
326
327 if (!dev)
328 return ERR_PTR(-EINVAL);
329
330 handle = ACPI_HANDLE(dev);
331 if (!handle || acpi_bus_get_device(handle, &adev))
332 return ERR_PTR(-ENODEV);
333
334 memset(&lookup, 0, sizeof(lookup));
335 lookup.index = index;
336
337 INIT_LIST_HEAD(&resource_list);
338 ret = acpi_dev_get_resources(adev, &resource_list, acpi_find_gpio,
339 &lookup);
340 if (ret < 0)
341 return ERR_PTR(ret);
342
343 acpi_dev_free_resource_list(&resource_list);
344
345 if (lookup.desc && info)
346 *info = lookup.info;
347
348 return lookup.desc ? lookup.desc : ERR_PTR(-ENOENT);
349}
350
351static acpi_status
352acpi_gpio_adr_space_handler(u32 function, acpi_physical_address address,
353 u32 bits, u64 *value, void *handler_context,
354 void *region_context)
355{
356 struct acpi_gpio_chip *achip = region_context;
357 struct gpio_chip *chip = achip->chip;
358 struct acpi_resource_gpio *agpio;
359 struct acpi_resource *ares;
360 acpi_status status;
361 bool pull_up;
362 int i;
363
364 status = acpi_buffer_to_resource(achip->conn_info.connection,
365 achip->conn_info.length, &ares);
366 if (ACPI_FAILURE(status))
367 return status;
368
369 if (WARN_ON(ares->type != ACPI_RESOURCE_TYPE_GPIO)) {
370 ACPI_FREE(ares);
371 return AE_BAD_PARAMETER;
372 }
373
374 agpio = &ares->data.gpio;
375 pull_up = agpio->pin_config == ACPI_PIN_CONFIG_PULLUP;
376
377 if (WARN_ON(agpio->io_restriction == ACPI_IO_RESTRICT_INPUT &&
378 function == ACPI_WRITE)) {
379 ACPI_FREE(ares);
380 return AE_BAD_PARAMETER;
381 }
382
383 for (i = 0; i < agpio->pin_table_length; i++) {
384 unsigned pin = agpio->pin_table[i];
385 struct acpi_gpio_connection *conn;
386 struct gpio_desc *desc;
387 bool found;
388
389 desc = gpiochip_get_desc(chip, pin);
390 if (IS_ERR(desc)) {
391 status = AE_ERROR;
392 goto out;
393 }
394
395 mutex_lock(&achip->conn_lock);
396
397 found = false;
398 list_for_each_entry(conn, &achip->conns, node) {
399 if (conn->desc == desc) {
400 found = true;
401 break;
402 }
403 }
404 if (!found) {
405 int ret;
406
407 ret = gpiochip_request_own_desc(desc, "ACPI:OpRegion");
408 if (ret) {
409 status = AE_ERROR;
410 mutex_unlock(&achip->conn_lock);
411 goto out;
412 }
413
414 switch (agpio->io_restriction) {
415 case ACPI_IO_RESTRICT_INPUT:
416 gpiod_direction_input(desc);
417 break;
418 case ACPI_IO_RESTRICT_OUTPUT:
419 /*
420 * ACPI GPIO resources don't contain an
421 * initial value for the GPIO. Therefore we
422 * deduce that value from the pull field
423 * instead. If the pin is pulled up we
424 * assume default to be high, otherwise
425 * low.
426 */
427 gpiod_direction_output(desc, pull_up);
428 break;
429 default:
430 /*
431 * Assume that the BIOS has configured the
432 * direction and pull accordingly.
433 */
434 break;
435 }
436
437 conn = kzalloc(sizeof(*conn), GFP_KERNEL);
438 if (!conn) {
439 status = AE_NO_MEMORY;
440 gpiochip_free_own_desc(desc);
441 mutex_unlock(&achip->conn_lock);
442 goto out;
443 }
444
445 conn->desc = desc;
446 list_add_tail(&conn->node, &achip->conns);
447 }
448
449 mutex_unlock(&achip->conn_lock);
450
451 if (function == ACPI_WRITE)
452 gpiod_set_raw_value(desc, !!((1 << i) & *value));
453 else
454 *value |= (u64)gpiod_get_raw_value(desc) << i;
455 }
456
457out:
458 ACPI_FREE(ares);
459 return status;
460}
461
462static void acpi_gpiochip_request_regions(struct acpi_gpio_chip *achip)
463{
464 struct gpio_chip *chip = achip->chip;
465 acpi_handle handle = ACPI_HANDLE(chip->dev);
466 acpi_status status;
467
468 INIT_LIST_HEAD(&achip->conns);
469 mutex_init(&achip->conn_lock);
470 status = acpi_install_address_space_handler(handle, ACPI_ADR_SPACE_GPIO,
471 acpi_gpio_adr_space_handler,
472 NULL, achip);
473 if (ACPI_FAILURE(status))
474 dev_err(chip->dev, "Failed to install GPIO OpRegion handler\n");
475}
476
477static void acpi_gpiochip_free_regions(struct acpi_gpio_chip *achip)
478{
479 struct gpio_chip *chip = achip->chip;
480 acpi_handle handle = ACPI_HANDLE(chip->dev);
481 struct acpi_gpio_connection *conn, *tmp;
482 acpi_status status;
483
484 status = acpi_remove_address_space_handler(handle, ACPI_ADR_SPACE_GPIO,
485 acpi_gpio_adr_space_handler);
486 if (ACPI_FAILURE(status)) {
487 dev_err(chip->dev, "Failed to remove GPIO OpRegion handler\n");
488 return;
489 }
490
491 list_for_each_entry_safe_reverse(conn, tmp, &achip->conns, node) {
492 gpiochip_free_own_desc(conn->desc);
493 list_del(&conn->node);
494 kfree(conn);
495 }
496}
497
498void acpi_gpiochip_add(struct gpio_chip *chip)
499{
500 struct acpi_gpio_chip *acpi_gpio;
501 acpi_handle handle;
502 acpi_status status;
503
504 if (!chip || !chip->dev)
505 return;
506
507 handle = ACPI_HANDLE(chip->dev);
508 if (!handle)
509 return;
510
511 acpi_gpio = kzalloc(sizeof(*acpi_gpio), GFP_KERNEL);
512 if (!acpi_gpio) {
513 dev_err(chip->dev,
514 "Failed to allocate memory for ACPI GPIO chip\n");
515 return;
516 }
517
518 acpi_gpio->chip = chip;
519
520 status = acpi_attach_data(handle, acpi_gpio_chip_dh, acpi_gpio);
521 if (ACPI_FAILURE(status)) {
522 dev_err(chip->dev, "Failed to attach ACPI GPIO chip\n");
523 kfree(acpi_gpio);
524 return;
525 }
526
527 acpi_gpiochip_request_interrupts(acpi_gpio);
528 acpi_gpiochip_request_regions(acpi_gpio);
529}
530
531void acpi_gpiochip_remove(struct gpio_chip *chip)
532{
533 struct acpi_gpio_chip *acpi_gpio;
534 acpi_handle handle;
535 acpi_status status;
536
537 if (!chip || !chip->dev)
538 return;
539
540 handle = ACPI_HANDLE(chip->dev);
541 if (!handle)
542 return;
543
544 status = acpi_get_data(handle, acpi_gpio_chip_dh, (void **)&acpi_gpio);
545 if (ACPI_FAILURE(status)) {
546 dev_warn(chip->dev, "Failed to retrieve ACPI GPIO chip\n");
547 return;
548 }
549
550 acpi_gpiochip_free_regions(acpi_gpio);
551 acpi_gpiochip_free_interrupts(acpi_gpio);
552
553 acpi_detach_data(handle, acpi_gpio_chip_dh);
554 kfree(acpi_gpio);
555}
1/*
2 * ACPI helpers for GPIO API
3 *
4 * Copyright (C) 2012, Intel Corporation
5 * Authors: Mathias Nyman <mathias.nyman@linux.intel.com>
6 * Mika Westerberg <mika.westerberg@linux.intel.com>
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License version 2 as
10 * published by the Free Software Foundation.
11 */
12
13#include <linux/errno.h>
14#include <linux/gpio.h>
15#include <linux/gpio/consumer.h>
16#include <linux/gpio/driver.h>
17#include <linux/export.h>
18#include <linux/acpi.h>
19#include <linux/interrupt.h>
20#include <linux/mutex.h>
21#include <linux/pinctrl/pinctrl.h>
22
23#include "gpiolib.h"
24
25struct acpi_gpio_event {
26 struct list_head node;
27 acpi_handle handle;
28 unsigned int pin;
29 unsigned int irq;
30 struct gpio_desc *desc;
31};
32
33struct acpi_gpio_connection {
34 struct list_head node;
35 unsigned int pin;
36 struct gpio_desc *desc;
37};
38
39struct acpi_gpio_chip {
40 /*
41 * ACPICA requires that the first field of the context parameter
42 * passed to acpi_install_address_space_handler() is large enough
43 * to hold struct acpi_connection_info.
44 */
45 struct acpi_connection_info conn_info;
46 struct list_head conns;
47 struct mutex conn_lock;
48 struct gpio_chip *chip;
49 struct list_head events;
50};
51
52static int acpi_gpiochip_find(struct gpio_chip *gc, void *data)
53{
54 if (!gc->parent)
55 return false;
56
57 return ACPI_HANDLE(gc->parent) == data;
58}
59
60#ifdef CONFIG_PINCTRL
61/**
62 * acpi_gpiochip_pin_to_gpio_offset() - translates ACPI GPIO to Linux GPIO
63 * @chip: GPIO chip
64 * @pin: ACPI GPIO pin number from GpioIo/GpioInt resource
65 *
66 * Function takes ACPI GpioIo/GpioInt pin number as a parameter and
67 * translates it to a corresponding offset suitable to be passed to a
68 * GPIO controller driver.
69 *
70 * Typically the returned offset is same as @pin, but if the GPIO
71 * controller uses pin controller and the mapping is not contiguous the
72 * offset might be different.
73 */
74static int acpi_gpiochip_pin_to_gpio_offset(struct gpio_device *gdev, int pin)
75{
76 struct gpio_pin_range *pin_range;
77
78 /* If there are no ranges in this chip, use 1:1 mapping */
79 if (list_empty(&gdev->pin_ranges))
80 return pin;
81
82 list_for_each_entry(pin_range, &gdev->pin_ranges, node) {
83 const struct pinctrl_gpio_range *range = &pin_range->range;
84 int i;
85
86 if (range->pins) {
87 for (i = 0; i < range->npins; i++) {
88 if (range->pins[i] == pin)
89 return range->base + i - gdev->base;
90 }
91 } else {
92 if (pin >= range->pin_base &&
93 pin < range->pin_base + range->npins) {
94 unsigned gpio_base;
95
96 gpio_base = range->base - gdev->base;
97 return gpio_base + pin - range->pin_base;
98 }
99 }
100 }
101
102 return -EINVAL;
103}
104#else
105static inline int acpi_gpiochip_pin_to_gpio_offset(struct gpio_device *gdev,
106 int pin)
107{
108 return pin;
109}
110#endif
111
112/**
113 * acpi_get_gpiod() - Translate ACPI GPIO pin to GPIO descriptor usable with GPIO API
114 * @path: ACPI GPIO controller full path name, (e.g. "\\_SB.GPO1")
115 * @pin: ACPI GPIO pin number (0-based, controller-relative)
116 *
117 * Return: GPIO descriptor to use with Linux generic GPIO API, or ERR_PTR
118 * error value. Specifically returns %-EPROBE_DEFER if the referenced GPIO
119 * controller does not have gpiochip registered at the moment. This is to
120 * support probe deferral.
121 */
122static struct gpio_desc *acpi_get_gpiod(char *path, int pin)
123{
124 struct gpio_chip *chip;
125 acpi_handle handle;
126 acpi_status status;
127 int offset;
128
129 status = acpi_get_handle(NULL, path, &handle);
130 if (ACPI_FAILURE(status))
131 return ERR_PTR(-ENODEV);
132
133 chip = gpiochip_find(handle, acpi_gpiochip_find);
134 if (!chip)
135 return ERR_PTR(-EPROBE_DEFER);
136
137 offset = acpi_gpiochip_pin_to_gpio_offset(chip->gpiodev, pin);
138 if (offset < 0)
139 return ERR_PTR(offset);
140
141 return gpiochip_get_desc(chip, offset);
142}
143
144static irqreturn_t acpi_gpio_irq_handler(int irq, void *data)
145{
146 struct acpi_gpio_event *event = data;
147
148 acpi_evaluate_object(event->handle, NULL, NULL, NULL);
149
150 return IRQ_HANDLED;
151}
152
153static irqreturn_t acpi_gpio_irq_handler_evt(int irq, void *data)
154{
155 struct acpi_gpio_event *event = data;
156
157 acpi_execute_simple_method(event->handle, NULL, event->pin);
158
159 return IRQ_HANDLED;
160}
161
162static void acpi_gpio_chip_dh(acpi_handle handle, void *data)
163{
164 /* The address of this function is used as a key. */
165}
166
167static acpi_status acpi_gpiochip_request_interrupt(struct acpi_resource *ares,
168 void *context)
169{
170 struct acpi_gpio_chip *acpi_gpio = context;
171 struct gpio_chip *chip = acpi_gpio->chip;
172 struct acpi_resource_gpio *agpio;
173 acpi_handle handle, evt_handle;
174 struct acpi_gpio_event *event;
175 irq_handler_t handler = NULL;
176 struct gpio_desc *desc;
177 unsigned long irqflags;
178 int ret, pin, irq;
179
180 if (ares->type != ACPI_RESOURCE_TYPE_GPIO)
181 return AE_OK;
182
183 agpio = &ares->data.gpio;
184 if (agpio->connection_type != ACPI_RESOURCE_GPIO_TYPE_INT)
185 return AE_OK;
186
187 handle = ACPI_HANDLE(chip->parent);
188 pin = agpio->pin_table[0];
189
190 if (pin <= 255) {
191 char ev_name[5];
192 sprintf(ev_name, "_%c%02X",
193 agpio->triggering == ACPI_EDGE_SENSITIVE ? 'E' : 'L',
194 pin);
195 if (ACPI_SUCCESS(acpi_get_handle(handle, ev_name, &evt_handle)))
196 handler = acpi_gpio_irq_handler;
197 }
198 if (!handler) {
199 if (ACPI_SUCCESS(acpi_get_handle(handle, "_EVT", &evt_handle)))
200 handler = acpi_gpio_irq_handler_evt;
201 }
202 if (!handler)
203 return AE_BAD_PARAMETER;
204
205 pin = acpi_gpiochip_pin_to_gpio_offset(chip->gpiodev, pin);
206 if (pin < 0)
207 return AE_BAD_PARAMETER;
208
209 desc = gpiochip_request_own_desc(chip, pin, "ACPI:Event");
210 if (IS_ERR(desc)) {
211 dev_err(chip->parent, "Failed to request GPIO\n");
212 return AE_ERROR;
213 }
214
215 gpiod_direction_input(desc);
216
217 ret = gpiochip_lock_as_irq(chip, pin);
218 if (ret) {
219 dev_err(chip->parent, "Failed to lock GPIO as interrupt\n");
220 goto fail_free_desc;
221 }
222
223 irq = gpiod_to_irq(desc);
224 if (irq < 0) {
225 dev_err(chip->parent, "Failed to translate GPIO to IRQ\n");
226 goto fail_unlock_irq;
227 }
228
229 irqflags = IRQF_ONESHOT;
230 if (agpio->triggering == ACPI_LEVEL_SENSITIVE) {
231 if (agpio->polarity == ACPI_ACTIVE_HIGH)
232 irqflags |= IRQF_TRIGGER_HIGH;
233 else
234 irqflags |= IRQF_TRIGGER_LOW;
235 } else {
236 switch (agpio->polarity) {
237 case ACPI_ACTIVE_HIGH:
238 irqflags |= IRQF_TRIGGER_RISING;
239 break;
240 case ACPI_ACTIVE_LOW:
241 irqflags |= IRQF_TRIGGER_FALLING;
242 break;
243 default:
244 irqflags |= IRQF_TRIGGER_RISING |
245 IRQF_TRIGGER_FALLING;
246 break;
247 }
248 }
249
250 event = kzalloc(sizeof(*event), GFP_KERNEL);
251 if (!event)
252 goto fail_unlock_irq;
253
254 event->handle = evt_handle;
255 event->irq = irq;
256 event->pin = pin;
257 event->desc = desc;
258
259 ret = request_threaded_irq(event->irq, NULL, handler, irqflags,
260 "ACPI:Event", event);
261 if (ret) {
262 dev_err(chip->parent,
263 "Failed to setup interrupt handler for %d\n",
264 event->irq);
265 goto fail_free_event;
266 }
267
268 list_add_tail(&event->node, &acpi_gpio->events);
269 return AE_OK;
270
271fail_free_event:
272 kfree(event);
273fail_unlock_irq:
274 gpiochip_unlock_as_irq(chip, pin);
275fail_free_desc:
276 gpiochip_free_own_desc(desc);
277
278 return AE_ERROR;
279}
280
281/**
282 * acpi_gpiochip_request_interrupts() - Register isr for gpio chip ACPI events
283 * @chip: GPIO chip
284 *
285 * ACPI5 platforms can use GPIO signaled ACPI events. These GPIO interrupts are
286 * handled by ACPI event methods which need to be called from the GPIO
287 * chip's interrupt handler. acpi_gpiochip_request_interrupts finds out which
288 * gpio pins have acpi event methods and assigns interrupt handlers that calls
289 * the acpi event methods for those pins.
290 */
291void acpi_gpiochip_request_interrupts(struct gpio_chip *chip)
292{
293 struct acpi_gpio_chip *acpi_gpio;
294 acpi_handle handle;
295 acpi_status status;
296
297 if (!chip->parent || !chip->to_irq)
298 return;
299
300 handle = ACPI_HANDLE(chip->parent);
301 if (!handle)
302 return;
303
304 status = acpi_get_data(handle, acpi_gpio_chip_dh, (void **)&acpi_gpio);
305 if (ACPI_FAILURE(status))
306 return;
307
308 acpi_walk_resources(handle, "_AEI",
309 acpi_gpiochip_request_interrupt, acpi_gpio);
310}
311EXPORT_SYMBOL_GPL(acpi_gpiochip_request_interrupts);
312
313/**
314 * acpi_gpiochip_free_interrupts() - Free GPIO ACPI event interrupts.
315 * @chip: GPIO chip
316 *
317 * Free interrupts associated with GPIO ACPI event method for the given
318 * GPIO chip.
319 */
320void acpi_gpiochip_free_interrupts(struct gpio_chip *chip)
321{
322 struct acpi_gpio_chip *acpi_gpio;
323 struct acpi_gpio_event *event, *ep;
324 acpi_handle handle;
325 acpi_status status;
326
327 if (!chip->parent || !chip->to_irq)
328 return;
329
330 handle = ACPI_HANDLE(chip->parent);
331 if (!handle)
332 return;
333
334 status = acpi_get_data(handle, acpi_gpio_chip_dh, (void **)&acpi_gpio);
335 if (ACPI_FAILURE(status))
336 return;
337
338 list_for_each_entry_safe_reverse(event, ep, &acpi_gpio->events, node) {
339 struct gpio_desc *desc;
340
341 free_irq(event->irq, event);
342 desc = event->desc;
343 if (WARN_ON(IS_ERR(desc)))
344 continue;
345 gpiochip_unlock_as_irq(chip, event->pin);
346 gpiochip_free_own_desc(desc);
347 list_del(&event->node);
348 kfree(event);
349 }
350}
351EXPORT_SYMBOL_GPL(acpi_gpiochip_free_interrupts);
352
353int acpi_dev_add_driver_gpios(struct acpi_device *adev,
354 const struct acpi_gpio_mapping *gpios)
355{
356 if (adev && gpios) {
357 adev->driver_gpios = gpios;
358 return 0;
359 }
360 return -EINVAL;
361}
362EXPORT_SYMBOL_GPL(acpi_dev_add_driver_gpios);
363
364static bool acpi_get_driver_gpio_data(struct acpi_device *adev,
365 const char *name, int index,
366 struct acpi_reference_args *args)
367{
368 const struct acpi_gpio_mapping *gm;
369
370 if (!adev->driver_gpios)
371 return false;
372
373 for (gm = adev->driver_gpios; gm->name; gm++)
374 if (!strcmp(name, gm->name) && gm->data && index < gm->size) {
375 const struct acpi_gpio_params *par = gm->data + index;
376
377 args->adev = adev;
378 args->args[0] = par->crs_entry_index;
379 args->args[1] = par->line_index;
380 args->args[2] = par->active_low;
381 args->nargs = 3;
382 return true;
383 }
384
385 return false;
386}
387
388struct acpi_gpio_lookup {
389 struct acpi_gpio_info info;
390 int index;
391 int pin_index;
392 bool active_low;
393 struct acpi_device *adev;
394 struct gpio_desc *desc;
395 int n;
396};
397
398static int acpi_find_gpio(struct acpi_resource *ares, void *data)
399{
400 struct acpi_gpio_lookup *lookup = data;
401
402 if (ares->type != ACPI_RESOURCE_TYPE_GPIO)
403 return 1;
404
405 if (lookup->n++ == lookup->index && !lookup->desc) {
406 const struct acpi_resource_gpio *agpio = &ares->data.gpio;
407 int pin_index = lookup->pin_index;
408
409 if (pin_index >= agpio->pin_table_length)
410 return 1;
411
412 lookup->desc = acpi_get_gpiod(agpio->resource_source.string_ptr,
413 agpio->pin_table[pin_index]);
414 lookup->info.gpioint =
415 agpio->connection_type == ACPI_RESOURCE_GPIO_TYPE_INT;
416
417 /*
418 * ActiveLow is only specified for GpioInt resource. If
419 * GpioIo is used then the only way to set the flag is
420 * to use _DSD "gpios" property.
421 * Note: we expect here:
422 * - ACPI_ACTIVE_LOW == GPIO_ACTIVE_LOW
423 * - ACPI_ACTIVE_HIGH == GPIO_ACTIVE_HIGH
424 */
425 if (lookup->info.gpioint) {
426 lookup->info.polarity = agpio->polarity;
427 lookup->info.triggering = agpio->triggering;
428 }
429
430 }
431
432 return 1;
433}
434
435static int acpi_gpio_resource_lookup(struct acpi_gpio_lookup *lookup,
436 struct acpi_gpio_info *info)
437{
438 struct list_head res_list;
439 int ret;
440
441 INIT_LIST_HEAD(&res_list);
442
443 ret = acpi_dev_get_resources(lookup->adev, &res_list, acpi_find_gpio,
444 lookup);
445 if (ret < 0)
446 return ret;
447
448 acpi_dev_free_resource_list(&res_list);
449
450 if (!lookup->desc)
451 return -ENOENT;
452
453 if (info) {
454 *info = lookup->info;
455 if (lookup->active_low)
456 info->polarity = lookup->active_low;
457 }
458 return 0;
459}
460
461static int acpi_gpio_property_lookup(struct fwnode_handle *fwnode,
462 const char *propname, int index,
463 struct acpi_gpio_lookup *lookup)
464{
465 struct acpi_reference_args args;
466 int ret;
467
468 memset(&args, 0, sizeof(args));
469 ret = acpi_node_get_property_reference(fwnode, propname, index, &args);
470 if (ret) {
471 struct acpi_device *adev = to_acpi_device_node(fwnode);
472
473 if (!adev)
474 return ret;
475
476 if (!acpi_get_driver_gpio_data(adev, propname, index, &args))
477 return ret;
478 }
479 /*
480 * The property was found and resolved, so need to lookup the GPIO based
481 * on returned args.
482 */
483 lookup->adev = args.adev;
484 if (args.nargs >= 2) {
485 lookup->index = args.args[0];
486 lookup->pin_index = args.args[1];
487 /* 3rd argument, if present is used to specify active_low. */
488 if (args.nargs >= 3)
489 lookup->active_low = !!args.args[2];
490 }
491 return 0;
492}
493
494/**
495 * acpi_get_gpiod_by_index() - get a GPIO descriptor from device resources
496 * @adev: pointer to a ACPI device to get GPIO from
497 * @propname: Property name of the GPIO (optional)
498 * @index: index of GpioIo/GpioInt resource (starting from %0)
499 * @info: info pointer to fill in (optional)
500 *
501 * Function goes through ACPI resources for @adev and based on @index looks
502 * up a GpioIo/GpioInt resource, translates it to the Linux GPIO descriptor,
503 * and returns it. @index matches GpioIo/GpioInt resources only so if there
504 * are total %3 GPIO resources, the index goes from %0 to %2.
505 *
506 * If @propname is specified the GPIO is looked using device property. In
507 * that case @index is used to select the GPIO entry in the property value
508 * (in case of multiple).
509 *
510 * If the GPIO cannot be translated or there is an error an ERR_PTR is
511 * returned.
512 *
513 * Note: if the GPIO resource has multiple entries in the pin list, this
514 * function only returns the first.
515 */
516struct gpio_desc *acpi_get_gpiod_by_index(struct acpi_device *adev,
517 const char *propname, int index,
518 struct acpi_gpio_info *info)
519{
520 struct acpi_gpio_lookup lookup;
521 int ret;
522
523 if (!adev)
524 return ERR_PTR(-ENODEV);
525
526 memset(&lookup, 0, sizeof(lookup));
527 lookup.index = index;
528
529 if (propname) {
530 dev_dbg(&adev->dev, "GPIO: looking up %s\n", propname);
531
532 ret = acpi_gpio_property_lookup(acpi_fwnode_handle(adev),
533 propname, index, &lookup);
534 if (ret)
535 return ERR_PTR(ret);
536
537 dev_dbg(&adev->dev, "GPIO: _DSD returned %s %d %d %u\n",
538 dev_name(&lookup.adev->dev), lookup.index,
539 lookup.pin_index, lookup.active_low);
540 } else {
541 dev_dbg(&adev->dev, "GPIO: looking up %d in _CRS\n", index);
542 lookup.adev = adev;
543 }
544
545 ret = acpi_gpio_resource_lookup(&lookup, info);
546 return ret ? ERR_PTR(ret) : lookup.desc;
547}
548
549/**
550 * acpi_node_get_gpiod() - get a GPIO descriptor from ACPI resources
551 * @fwnode: pointer to an ACPI firmware node to get the GPIO information from
552 * @propname: Property name of the GPIO
553 * @index: index of GpioIo/GpioInt resource (starting from %0)
554 * @info: info pointer to fill in (optional)
555 *
556 * If @fwnode is an ACPI device object, call %acpi_get_gpiod_by_index() for it.
557 * Otherwise (ie. it is a data-only non-device object), use the property-based
558 * GPIO lookup to get to the GPIO resource with the relevant information and use
559 * that to obtain the GPIO descriptor to return.
560 */
561struct gpio_desc *acpi_node_get_gpiod(struct fwnode_handle *fwnode,
562 const char *propname, int index,
563 struct acpi_gpio_info *info)
564{
565 struct acpi_gpio_lookup lookup;
566 struct acpi_device *adev;
567 int ret;
568
569 adev = to_acpi_device_node(fwnode);
570 if (adev)
571 return acpi_get_gpiod_by_index(adev, propname, index, info);
572
573 if (!is_acpi_data_node(fwnode))
574 return ERR_PTR(-ENODEV);
575
576 if (!propname)
577 return ERR_PTR(-EINVAL);
578
579 memset(&lookup, 0, sizeof(lookup));
580 lookup.index = index;
581
582 ret = acpi_gpio_property_lookup(fwnode, propname, index, &lookup);
583 if (ret)
584 return ERR_PTR(ret);
585
586 ret = acpi_gpio_resource_lookup(&lookup, info);
587 return ret ? ERR_PTR(ret) : lookup.desc;
588}
589
590/**
591 * acpi_dev_gpio_irq_get() - Find GpioInt and translate it to Linux IRQ number
592 * @adev: pointer to a ACPI device to get IRQ from
593 * @index: index of GpioInt resource (starting from %0)
594 *
595 * If the device has one or more GpioInt resources, this function can be
596 * used to translate from the GPIO offset in the resource to the Linux IRQ
597 * number.
598 *
599 * Return: Linux IRQ number (>%0) on success, negative errno on failure.
600 */
601int acpi_dev_gpio_irq_get(struct acpi_device *adev, int index)
602{
603 int idx, i;
604 unsigned int irq_flags;
605
606 for (i = 0, idx = 0; idx <= index; i++) {
607 struct acpi_gpio_info info;
608 struct gpio_desc *desc;
609
610 desc = acpi_get_gpiod_by_index(adev, NULL, i, &info);
611 if (IS_ERR(desc))
612 break;
613 if (info.gpioint && idx++ == index) {
614 int irq = gpiod_to_irq(desc);
615
616 if (irq < 0)
617 return irq;
618
619 irq_flags = acpi_dev_get_irq_type(info.triggering,
620 info.polarity);
621
622 /* Set type if specified and different than the current one */
623 if (irq_flags != IRQ_TYPE_NONE &&
624 irq_flags != irq_get_trigger_type(irq))
625 irq_set_irq_type(irq, irq_flags);
626
627 return irq;
628 }
629
630 }
631 return -ENOENT;
632}
633EXPORT_SYMBOL_GPL(acpi_dev_gpio_irq_get);
634
635static acpi_status
636acpi_gpio_adr_space_handler(u32 function, acpi_physical_address address,
637 u32 bits, u64 *value, void *handler_context,
638 void *region_context)
639{
640 struct acpi_gpio_chip *achip = region_context;
641 struct gpio_chip *chip = achip->chip;
642 struct acpi_resource_gpio *agpio;
643 struct acpi_resource *ares;
644 int pin_index = (int)address;
645 acpi_status status;
646 bool pull_up;
647 int length;
648 int i;
649
650 status = acpi_buffer_to_resource(achip->conn_info.connection,
651 achip->conn_info.length, &ares);
652 if (ACPI_FAILURE(status))
653 return status;
654
655 if (WARN_ON(ares->type != ACPI_RESOURCE_TYPE_GPIO)) {
656 ACPI_FREE(ares);
657 return AE_BAD_PARAMETER;
658 }
659
660 agpio = &ares->data.gpio;
661 pull_up = agpio->pin_config == ACPI_PIN_CONFIG_PULLUP;
662
663 if (WARN_ON(agpio->io_restriction == ACPI_IO_RESTRICT_INPUT &&
664 function == ACPI_WRITE)) {
665 ACPI_FREE(ares);
666 return AE_BAD_PARAMETER;
667 }
668
669 length = min(agpio->pin_table_length, (u16)(pin_index + bits));
670 for (i = pin_index; i < length; ++i) {
671 int pin = agpio->pin_table[i];
672 struct acpi_gpio_connection *conn;
673 struct gpio_desc *desc;
674 bool found;
675
676 pin = acpi_gpiochip_pin_to_gpio_offset(chip->gpiodev, pin);
677 if (pin < 0) {
678 status = AE_BAD_PARAMETER;
679 goto out;
680 }
681
682 mutex_lock(&achip->conn_lock);
683
684 found = false;
685 list_for_each_entry(conn, &achip->conns, node) {
686 if (conn->pin == pin) {
687 found = true;
688 desc = conn->desc;
689 break;
690 }
691 }
692
693 /*
694 * The same GPIO can be shared between operation region and
695 * event but only if the access here is ACPI_READ. In that
696 * case we "borrow" the event GPIO instead.
697 */
698 if (!found && agpio->sharable == ACPI_SHARED &&
699 function == ACPI_READ) {
700 struct acpi_gpio_event *event;
701
702 list_for_each_entry(event, &achip->events, node) {
703 if (event->pin == pin) {
704 desc = event->desc;
705 found = true;
706 break;
707 }
708 }
709 }
710
711 if (!found) {
712 desc = gpiochip_request_own_desc(chip, pin,
713 "ACPI:OpRegion");
714 if (IS_ERR(desc)) {
715 status = AE_ERROR;
716 mutex_unlock(&achip->conn_lock);
717 goto out;
718 }
719
720 switch (agpio->io_restriction) {
721 case ACPI_IO_RESTRICT_INPUT:
722 gpiod_direction_input(desc);
723 break;
724 case ACPI_IO_RESTRICT_OUTPUT:
725 /*
726 * ACPI GPIO resources don't contain an
727 * initial value for the GPIO. Therefore we
728 * deduce that value from the pull field
729 * instead. If the pin is pulled up we
730 * assume default to be high, otherwise
731 * low.
732 */
733 gpiod_direction_output(desc, pull_up);
734 break;
735 default:
736 /*
737 * Assume that the BIOS has configured the
738 * direction and pull accordingly.
739 */
740 break;
741 }
742
743 conn = kzalloc(sizeof(*conn), GFP_KERNEL);
744 if (!conn) {
745 status = AE_NO_MEMORY;
746 gpiochip_free_own_desc(desc);
747 mutex_unlock(&achip->conn_lock);
748 goto out;
749 }
750
751 conn->pin = pin;
752 conn->desc = desc;
753 list_add_tail(&conn->node, &achip->conns);
754 }
755
756 mutex_unlock(&achip->conn_lock);
757
758 if (function == ACPI_WRITE)
759 gpiod_set_raw_value_cansleep(desc,
760 !!((1 << i) & *value));
761 else
762 *value |= (u64)gpiod_get_raw_value_cansleep(desc) << i;
763 }
764
765out:
766 ACPI_FREE(ares);
767 return status;
768}
769
770static void acpi_gpiochip_request_regions(struct acpi_gpio_chip *achip)
771{
772 struct gpio_chip *chip = achip->chip;
773 acpi_handle handle = ACPI_HANDLE(chip->parent);
774 acpi_status status;
775
776 INIT_LIST_HEAD(&achip->conns);
777 mutex_init(&achip->conn_lock);
778 status = acpi_install_address_space_handler(handle, ACPI_ADR_SPACE_GPIO,
779 acpi_gpio_adr_space_handler,
780 NULL, achip);
781 if (ACPI_FAILURE(status))
782 dev_err(chip->parent,
783 "Failed to install GPIO OpRegion handler\n");
784}
785
786static void acpi_gpiochip_free_regions(struct acpi_gpio_chip *achip)
787{
788 struct gpio_chip *chip = achip->chip;
789 acpi_handle handle = ACPI_HANDLE(chip->parent);
790 struct acpi_gpio_connection *conn, *tmp;
791 acpi_status status;
792
793 status = acpi_remove_address_space_handler(handle, ACPI_ADR_SPACE_GPIO,
794 acpi_gpio_adr_space_handler);
795 if (ACPI_FAILURE(status)) {
796 dev_err(chip->parent,
797 "Failed to remove GPIO OpRegion handler\n");
798 return;
799 }
800
801 list_for_each_entry_safe_reverse(conn, tmp, &achip->conns, node) {
802 gpiochip_free_own_desc(conn->desc);
803 list_del(&conn->node);
804 kfree(conn);
805 }
806}
807
808void acpi_gpiochip_add(struct gpio_chip *chip)
809{
810 struct acpi_gpio_chip *acpi_gpio;
811 acpi_handle handle;
812 acpi_status status;
813
814 if (!chip || !chip->parent)
815 return;
816
817 handle = ACPI_HANDLE(chip->parent);
818 if (!handle)
819 return;
820
821 acpi_gpio = kzalloc(sizeof(*acpi_gpio), GFP_KERNEL);
822 if (!acpi_gpio) {
823 dev_err(chip->parent,
824 "Failed to allocate memory for ACPI GPIO chip\n");
825 return;
826 }
827
828 acpi_gpio->chip = chip;
829 INIT_LIST_HEAD(&acpi_gpio->events);
830
831 status = acpi_attach_data(handle, acpi_gpio_chip_dh, acpi_gpio);
832 if (ACPI_FAILURE(status)) {
833 dev_err(chip->parent, "Failed to attach ACPI GPIO chip\n");
834 kfree(acpi_gpio);
835 return;
836 }
837
838 acpi_gpiochip_request_regions(acpi_gpio);
839}
840
841void acpi_gpiochip_remove(struct gpio_chip *chip)
842{
843 struct acpi_gpio_chip *acpi_gpio;
844 acpi_handle handle;
845 acpi_status status;
846
847 if (!chip || !chip->parent)
848 return;
849
850 handle = ACPI_HANDLE(chip->parent);
851 if (!handle)
852 return;
853
854 status = acpi_get_data(handle, acpi_gpio_chip_dh, (void **)&acpi_gpio);
855 if (ACPI_FAILURE(status)) {
856 dev_warn(chip->parent, "Failed to retrieve ACPI GPIO chip\n");
857 return;
858 }
859
860 acpi_gpiochip_free_regions(acpi_gpio);
861
862 acpi_detach_data(handle, acpi_gpio_chip_dh);
863 kfree(acpi_gpio);
864}
865
866static unsigned int acpi_gpio_package_count(const union acpi_object *obj)
867{
868 const union acpi_object *element = obj->package.elements;
869 const union acpi_object *end = element + obj->package.count;
870 unsigned int count = 0;
871
872 while (element < end) {
873 if (element->type == ACPI_TYPE_LOCAL_REFERENCE)
874 count++;
875
876 element++;
877 }
878 return count;
879}
880
881static int acpi_find_gpio_count(struct acpi_resource *ares, void *data)
882{
883 unsigned int *count = data;
884
885 if (ares->type == ACPI_RESOURCE_TYPE_GPIO)
886 *count += ares->data.gpio.pin_table_length;
887
888 return 1;
889}
890
891/**
892 * acpi_gpio_count - return the number of GPIOs associated with a
893 * device / function or -ENOENT if no GPIO has been
894 * assigned to the requested function.
895 * @dev: GPIO consumer, can be NULL for system-global GPIOs
896 * @con_id: function within the GPIO consumer
897 */
898int acpi_gpio_count(struct device *dev, const char *con_id)
899{
900 struct acpi_device *adev = ACPI_COMPANION(dev);
901 const union acpi_object *obj;
902 const struct acpi_gpio_mapping *gm;
903 int count = -ENOENT;
904 int ret;
905 char propname[32];
906 unsigned int i;
907
908 /* Try first from _DSD */
909 for (i = 0; i < ARRAY_SIZE(gpio_suffixes); i++) {
910 if (con_id && strcmp(con_id, "gpios"))
911 snprintf(propname, sizeof(propname), "%s-%s",
912 con_id, gpio_suffixes[i]);
913 else
914 snprintf(propname, sizeof(propname), "%s",
915 gpio_suffixes[i]);
916
917 ret = acpi_dev_get_property(adev, propname, ACPI_TYPE_ANY,
918 &obj);
919 if (ret == 0) {
920 if (obj->type == ACPI_TYPE_LOCAL_REFERENCE)
921 count = 1;
922 else if (obj->type == ACPI_TYPE_PACKAGE)
923 count = acpi_gpio_package_count(obj);
924 } else if (adev->driver_gpios) {
925 for (gm = adev->driver_gpios; gm->name; gm++)
926 if (strcmp(propname, gm->name) == 0) {
927 count = gm->size;
928 break;
929 }
930 }
931 if (count >= 0)
932 break;
933 }
934
935 /* Then from plain _CRS GPIOs */
936 if (count < 0) {
937 struct list_head resource_list;
938 unsigned int crs_count = 0;
939
940 INIT_LIST_HEAD(&resource_list);
941 acpi_dev_get_resources(adev, &resource_list,
942 acpi_find_gpio_count, &crs_count);
943 acpi_dev_free_resource_list(&resource_list);
944 if (crs_count > 0)
945 count = crs_count;
946 }
947 return count;
948}
949
950struct acpi_crs_lookup {
951 struct list_head node;
952 struct acpi_device *adev;
953 const char *con_id;
954};
955
956static DEFINE_MUTEX(acpi_crs_lookup_lock);
957static LIST_HEAD(acpi_crs_lookup_list);
958
959bool acpi_can_fallback_to_crs(struct acpi_device *adev, const char *con_id)
960{
961 struct acpi_crs_lookup *l, *lookup = NULL;
962
963 /* Never allow fallback if the device has properties */
964 if (adev->data.properties || adev->driver_gpios)
965 return false;
966
967 mutex_lock(&acpi_crs_lookup_lock);
968
969 list_for_each_entry(l, &acpi_crs_lookup_list, node) {
970 if (l->adev == adev) {
971 lookup = l;
972 break;
973 }
974 }
975
976 if (!lookup) {
977 lookup = kmalloc(sizeof(*lookup), GFP_KERNEL);
978 if (lookup) {
979 lookup->adev = adev;
980 lookup->con_id = kstrdup(con_id, GFP_KERNEL);
981 list_add_tail(&lookup->node, &acpi_crs_lookup_list);
982 }
983 }
984
985 mutex_unlock(&acpi_crs_lookup_lock);
986
987 return lookup &&
988 ((!lookup->con_id && !con_id) ||
989 (lookup->con_id && con_id &&
990 strcmp(lookup->con_id, con_id) == 0));
991}