?  search:
summary | log | graphiclog1 | graphiclog2 | commit | commitdiff | tree | refs | edit | fork
blame | history | raw | HEAD
Linux 4.19-rc5
[linux/fpc-iii.git] / drivers / gpio / gpiolib-acpi.c
blob8b9d7e42c600b60d26bad7f26c32ed938be6e7a2
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/gpio/machine.h>
18 #include <linux/export.h>
19 #include <linux/acpi.h>
20 #include <linux/interrupt.h>
21 #include <linux/mutex.h>
22 #include <linux/pinctrl/pinctrl.h>
23
24 #include "gpiolib.h"
25
26 struct acpi_gpio_event {
27 struct list_head node;
28 acpi_handle handle;
29 unsigned int pin;
30 unsigned int irq;
31 struct gpio_desc *desc;
32 };
33
34 struct acpi_gpio_connection {
35 struct list_head node;
36 unsigned int pin;
37 struct gpio_desc *desc;
38 };
39
40 struct acpi_gpio_chip {
41 /*
42 * ACPICA requires that the first field of the context parameter
43 * passed to acpi_install_address_space_handler() is large enough
44 * to hold struct acpi_connection_info.
45 */
46 struct acpi_connection_info conn_info;
47 struct list_head conns;
48 struct mutex conn_lock;
49 struct gpio_chip *chip;
50 struct list_head events;
51 struct list_head deferred_req_irqs_list_entry;
52 };
53
54 /*
55 * For gpiochips which call acpi_gpiochip_request_interrupts() before late_init
56 * (so builtin drivers) we register the ACPI GpioInt event handlers from a
57 * late_initcall_sync handler, so that other builtin drivers can register their
58 * OpRegions before the event handlers can run. This list contains gpiochips
59 * for which the acpi_gpiochip_request_interrupts() has been deferred.
60 */
61 static DEFINE_MUTEX(acpi_gpio_deferred_req_irqs_lock);
62 static LIST_HEAD(acpi_gpio_deferred_req_irqs_list);
63 static bool acpi_gpio_deferred_req_irqs_done;
64
65 static int acpi_gpiochip_find(struct gpio_chip *gc, void *data)
66 {
67 if (!gc->parent)
68 return false;
69
70 return ACPI_HANDLE(gc->parent) == data;
71 }
72
73 /**
74 * acpi_get_gpiod() - Translate ACPI GPIO pin to GPIO descriptor usable with GPIO API
75 * @path: ACPI GPIO controller full path name, (e.g. "\\_SB.GPO1")
76 * @pin: ACPI GPIO pin number (0-based, controller-relative)
77 *
78 * Return: GPIO descriptor to use with Linux generic GPIO API, or ERR_PTR
79 * error value. Specifically returns %-EPROBE_DEFER if the referenced GPIO
80 * controller does not have gpiochip registered at the moment. This is to
81 * support probe deferral.
82 */
83 static struct gpio_desc *acpi_get_gpiod(char *path, int pin)
84 {
85 struct gpio_chip *chip;
86 acpi_handle handle;
87 acpi_status status;
88
89 status = acpi_get_handle(NULL, path, &handle);
90 if (ACPI_FAILURE(status))
91 return ERR_PTR(-ENODEV);
92
93 chip = gpiochip_find(handle, acpi_gpiochip_find);
94 if (!chip)
95 return ERR_PTR(-EPROBE_DEFER);
96
97 return gpiochip_get_desc(chip, pin);
98 }
99
100 static irqreturn_t acpi_gpio_irq_handler(int irq, void *data)
101 {
102 struct acpi_gpio_event *event = data;
103
104 acpi_evaluate_object(event->handle, NULL, NULL, NULL);
105
106 return IRQ_HANDLED;
107 }
108
109 static irqreturn_t acpi_gpio_irq_handler_evt(int irq, void *data)
110 {
111 struct acpi_gpio_event *event = data;
112
113 acpi_execute_simple_method(event->handle, NULL, event->pin);
114
115 return IRQ_HANDLED;
116 }
117
118 static void acpi_gpio_chip_dh(acpi_handle handle, void *data)
119 {
120 /* The address of this function is used as a key. */
121 }
122
123 bool acpi_gpio_get_irq_resource(struct acpi_resource *ares,
124 struct acpi_resource_gpio **agpio)
125 {
126 struct acpi_resource_gpio *gpio;
127
128 if (ares->type != ACPI_RESOURCE_TYPE_GPIO)
129 return false;
130
131 gpio = &ares->data.gpio;
132 if (gpio->connection_type != ACPI_RESOURCE_GPIO_TYPE_INT)
133 return false;
134
135 *agpio = gpio;
136 return true;
137 }
138 EXPORT_SYMBOL_GPL(acpi_gpio_get_irq_resource);
139
140 static acpi_status acpi_gpiochip_request_interrupt(struct acpi_resource *ares,
141 void *context)
142 {
143 struct acpi_gpio_chip *acpi_gpio = context;
144 struct gpio_chip *chip = acpi_gpio->chip;
145 struct acpi_resource_gpio *agpio;
146 acpi_handle handle, evt_handle;
147 struct acpi_gpio_event *event;
148 irq_handler_t handler = NULL;
149 struct gpio_desc *desc;
150 unsigned long irqflags;
151 int ret, pin, irq, value;
152
153 if (!acpi_gpio_get_irq_resource(ares, &agpio))
154 return AE_OK;
155
156 handle = ACPI_HANDLE(chip->parent);
157 pin = agpio->pin_table[0];
158
159 if (pin <= 255) {
160 char ev_name[5];
161 sprintf(ev_name, "_%c%02hhX",
162 agpio->triggering == ACPI_EDGE_SENSITIVE ? 'E' : 'L',
163 pin);
164 if (ACPI_SUCCESS(acpi_get_handle(handle, ev_name, &evt_handle)))
165 handler = acpi_gpio_irq_handler;
166 }
167 if (!handler) {
168 if (ACPI_SUCCESS(acpi_get_handle(handle, "_EVT", &evt_handle)))
169 handler = acpi_gpio_irq_handler_evt;
170 }
171 if (!handler)
172 return AE_OK;
173
174 desc = gpiochip_request_own_desc(chip, pin, "ACPI:Event");
175 if (IS_ERR(desc)) {
176 dev_err(chip->parent, "Failed to request GPIO\n");
177 return AE_ERROR;
178 }
179
180 gpiod_direction_input(desc);
181
182 value = gpiod_get_value_cansleep(desc);
183
184 ret = gpiochip_lock_as_irq(chip, pin);
185 if (ret) {
186 dev_err(chip->parent, "Failed to lock GPIO as interrupt\n");
187 goto fail_free_desc;
188 }
189
190 irq = gpiod_to_irq(desc);
191 if (irq < 0) {
192 dev_err(chip->parent, "Failed to translate GPIO to IRQ\n");
193 goto fail_unlock_irq;
194 }
195
196 irqflags = IRQF_ONESHOT;
197 if (agpio->triggering == ACPI_LEVEL_SENSITIVE) {
198 if (agpio->polarity == ACPI_ACTIVE_HIGH)
199 irqflags |= IRQF_TRIGGER_HIGH;
200 else
201 irqflags |= IRQF_TRIGGER_LOW;
202 } else {
203 switch (agpio->polarity) {
204 case ACPI_ACTIVE_HIGH:
205 irqflags |= IRQF_TRIGGER_RISING;
206 break;
207 case ACPI_ACTIVE_LOW:
208 irqflags |= IRQF_TRIGGER_FALLING;
209 break;
210 default:
211 irqflags |= IRQF_TRIGGER_RISING |
212 IRQF_TRIGGER_FALLING;
213 break;
214 }
215 }
216
217 event = kzalloc(sizeof(*event), GFP_KERNEL);
218 if (!event)
219 goto fail_unlock_irq;
220
221 event->handle = evt_handle;
222 event->irq = irq;
223 event->pin = pin;
224 event->desc = desc;
225
226 ret = request_threaded_irq(event->irq, NULL, handler, irqflags,
227 "ACPI:Event", event);
228 if (ret) {
229 dev_err(chip->parent,
230 "Failed to setup interrupt handler for %d\n",
231 event->irq);
232 goto fail_free_event;
233 }
234
235 if (agpio->wake_capable == ACPI_WAKE_CAPABLE)
236 enable_irq_wake(irq);
237
238 list_add_tail(&event->node, &acpi_gpio->events);
239
240 /*
241 * Make sure we trigger the initial state of the IRQ when using RISING
242 * or FALLING. Note we run the handlers on late_init, the AML code
243 * may refer to OperationRegions from other (builtin) drivers which
244 * may be probed after us.
245 */
246 if (((irqflags & IRQF_TRIGGER_RISING) && value == 1) ||
247 ((irqflags & IRQF_TRIGGER_FALLING) && value == 0))
248 handler(event->irq, event);
249
250 return AE_OK;
251
252 fail_free_event:
253 kfree(event);
254 fail_unlock_irq:
255 gpiochip_unlock_as_irq(chip, pin);
256 fail_free_desc:
257 gpiochip_free_own_desc(desc);
258
259 return AE_ERROR;
260 }
261
262 /**
263 * acpi_gpiochip_request_interrupts() - Register isr for gpio chip ACPI events
264 * @chip: GPIO chip
265 *
266 * ACPI5 platforms can use GPIO signaled ACPI events. These GPIO interrupts are
267 * handled by ACPI event methods which need to be called from the GPIO
268 * chip's interrupt handler. acpi_gpiochip_request_interrupts finds out which
269 * gpio pins have acpi event methods and assigns interrupt handlers that calls
270 * the acpi event methods for those pins.
271 */
272 void acpi_gpiochip_request_interrupts(struct gpio_chip *chip)
273 {
274 struct acpi_gpio_chip *acpi_gpio;
275 acpi_handle handle;
276 acpi_status status;
277 bool defer;
278
279 if (!chip->parent || !chip->to_irq)
280 return;
281
282 handle = ACPI_HANDLE(chip->parent);
283 if (!handle)
284 return;
285
286 status = acpi_get_data(handle, acpi_gpio_chip_dh, (void **)&acpi_gpio);
287 if (ACPI_FAILURE(status))
288 return;
289
290 mutex_lock(&acpi_gpio_deferred_req_irqs_lock);
291 defer = !acpi_gpio_deferred_req_irqs_done;
292 if (defer)
293 list_add(&acpi_gpio->deferred_req_irqs_list_entry,
294 &acpi_gpio_deferred_req_irqs_list);
295 mutex_unlock(&acpi_gpio_deferred_req_irqs_lock);
296
297 if (defer)
298 return;
299
300 acpi_walk_resources(handle, "_AEI",
301 acpi_gpiochip_request_interrupt, acpi_gpio);
302 }
303 EXPORT_SYMBOL_GPL(acpi_gpiochip_request_interrupts);
304
305 /**
306 * acpi_gpiochip_free_interrupts() - Free GPIO ACPI event interrupts.
307 * @chip: GPIO chip
308 *
309 * Free interrupts associated with GPIO ACPI event method for the given
310 * GPIO chip.
311 */
312 void acpi_gpiochip_free_interrupts(struct gpio_chip *chip)
313 {
314 struct acpi_gpio_chip *acpi_gpio;
315 struct acpi_gpio_event *event, *ep;
316 acpi_handle handle;
317 acpi_status status;
318
319 if (!chip->parent || !chip->to_irq)
320 return;
321
322 handle = ACPI_HANDLE(chip->parent);
323 if (!handle)
324 return;
325
326 status = acpi_get_data(handle, acpi_gpio_chip_dh, (void **)&acpi_gpio);
327 if (ACPI_FAILURE(status))
328 return;
329
330 mutex_lock(&acpi_gpio_deferred_req_irqs_lock);
331 if (!list_empty(&acpi_gpio->deferred_req_irqs_list_entry))
332 list_del_init(&acpi_gpio->deferred_req_irqs_list_entry);
333 mutex_unlock(&acpi_gpio_deferred_req_irqs_lock);
334
335 list_for_each_entry_safe_reverse(event, ep, &acpi_gpio->events, node) {
336 struct gpio_desc *desc;
337
338 if (irqd_is_wakeup_set(irq_get_irq_data(event->irq)))
339 disable_irq_wake(event->irq);
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 }
351 EXPORT_SYMBOL_GPL(acpi_gpiochip_free_interrupts);
352
353 int 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 }
362 EXPORT_SYMBOL_GPL(acpi_dev_add_driver_gpios);
363
364 static void devm_acpi_dev_release_driver_gpios(struct device *dev, void *res)
365 {
366 acpi_dev_remove_driver_gpios(ACPI_COMPANION(dev));
367 }
368
369 int devm_acpi_dev_add_driver_gpios(struct device *dev,
370 const struct acpi_gpio_mapping *gpios)
371 {
372 void *res;
373 int ret;
374
375 res = devres_alloc(devm_acpi_dev_release_driver_gpios, 0, GFP_KERNEL);
376 if (!res)
377 return -ENOMEM;
378
379 ret = acpi_dev_add_driver_gpios(ACPI_COMPANION(dev), gpios);
380 if (ret) {
381 devres_free(res);
382 return ret;
383 }
384 devres_add(dev, res);
385 return 0;
386 }
387 EXPORT_SYMBOL_GPL(devm_acpi_dev_add_driver_gpios);
388
389 void devm_acpi_dev_remove_driver_gpios(struct device *dev)
390 {
391 WARN_ON(devres_release(dev, devm_acpi_dev_release_driver_gpios, NULL, NULL));
392 }
393 EXPORT_SYMBOL_GPL(devm_acpi_dev_remove_driver_gpios);
394
395 static bool acpi_get_driver_gpio_data(struct acpi_device *adev,
396 const char *name, int index,
397 struct fwnode_reference_args *args,
398 unsigned int *quirks)
399 {
400 const struct acpi_gpio_mapping *gm;
401
402 if (!adev->driver_gpios)
403 return false;
404
405 for (gm = adev->driver_gpios; gm->name; gm++)
406 if (!strcmp(name, gm->name) && gm->data && index < gm->size) {
407 const struct acpi_gpio_params *par = gm->data + index;
408
409 args->fwnode = acpi_fwnode_handle(adev);
410 args->args[0] = par->crs_entry_index;
411 args->args[1] = par->line_index;
412 args->args[2] = par->active_low;
413 args->nargs = 3;
414
415 *quirks = gm->quirks;
416 return true;
417 }
418
419 return false;
420 }
421
422 static enum gpiod_flags
423 acpi_gpio_to_gpiod_flags(const struct acpi_resource_gpio *agpio)
424 {
425 bool pull_up = agpio->pin_config == ACPI_PIN_CONFIG_PULLUP;
426
427 switch (agpio->io_restriction) {
428 case ACPI_IO_RESTRICT_INPUT:
429 return GPIOD_IN;
430 case ACPI_IO_RESTRICT_OUTPUT:
431 /*
432 * ACPI GPIO resources don't contain an initial value for the
433 * GPIO. Therefore we deduce that value from the pull field
434 * instead. If the pin is pulled up we assume default to be
435 * high, otherwise low.
436 */
437 return pull_up ? GPIOD_OUT_HIGH : GPIOD_OUT_LOW;
438 default:
439 /*
440 * Assume that the BIOS has configured the direction and pull
441 * accordingly.
442 */
443 return GPIOD_ASIS;
444 }
445 }
446
447 static int
448 __acpi_gpio_update_gpiod_flags(enum gpiod_flags *flags, enum gpiod_flags update)
449 {
450 int ret = 0;
451
452 /*
453 * Check if the BIOS has IoRestriction with explicitly set direction
454 * and update @flags accordingly. Otherwise use whatever caller asked
455 * for.
456 */
457 if (update & GPIOD_FLAGS_BIT_DIR_SET) {
458 enum gpiod_flags diff = *flags ^ update;
459
460 /*
461 * Check if caller supplied incompatible GPIO initialization
462 * flags.
463 *
464 * Return %-EINVAL to notify that firmware has different
465 * settings and we are going to use them.
466 */
467 if (((*flags & GPIOD_FLAGS_BIT_DIR_SET) && (diff & GPIOD_FLAGS_BIT_DIR_OUT)) ||
468 ((*flags & GPIOD_FLAGS_BIT_DIR_OUT) && (diff & GPIOD_FLAGS_BIT_DIR_VAL)))
469 ret = -EINVAL;
470 *flags = update;
471 }
472 return ret;
473 }
474
475 int
476 acpi_gpio_update_gpiod_flags(enum gpiod_flags *flags, struct acpi_gpio_info *info)
477 {
478 struct device *dev = &info->adev->dev;
479 enum gpiod_flags old = *flags;
480 int ret;
481
482 ret = __acpi_gpio_update_gpiod_flags(&old, info->flags);
483 if (info->quirks & ACPI_GPIO_QUIRK_NO_IO_RESTRICTION) {
484 if (ret)
485 dev_warn(dev, FW_BUG "GPIO not in correct mode, fixing\n");
486 } else {
487 if (ret)
488 dev_dbg(dev, "Override GPIO initialization flags\n");
489 *flags = old;
490 }
491
492 return ret;
493 }
494
495 struct acpi_gpio_lookup {
496 struct acpi_gpio_info info;
497 int index;
498 int pin_index;
499 bool active_low;
500 struct gpio_desc *desc;
501 int n;
502 };
503
504 static int acpi_populate_gpio_lookup(struct acpi_resource *ares, void *data)
505 {
506 struct acpi_gpio_lookup *lookup = data;
507
508 if (ares->type != ACPI_RESOURCE_TYPE_GPIO)
509 return 1;
510
511 if (lookup->n++ == lookup->index && !lookup->desc) {
512 const struct acpi_resource_gpio *agpio = &ares->data.gpio;
513 int pin_index = lookup->pin_index;
514
515 if (pin_index >= agpio->pin_table_length)
516 return 1;
517
518 lookup->desc = acpi_get_gpiod(agpio->resource_source.string_ptr,
519 agpio->pin_table[pin_index]);
520 lookup->info.gpioint =
521 agpio->connection_type == ACPI_RESOURCE_GPIO_TYPE_INT;
522
523 /*
524 * Polarity and triggering are only specified for GpioInt
525 * resource.
526 * Note: we expect here:
527 * - ACPI_ACTIVE_LOW == GPIO_ACTIVE_LOW
528 * - ACPI_ACTIVE_HIGH == GPIO_ACTIVE_HIGH
529 */
530 if (lookup->info.gpioint) {
531 lookup->info.flags = GPIOD_IN;
532 lookup->info.polarity = agpio->polarity;
533 lookup->info.triggering = agpio->triggering;
534 } else {
535 lookup->info.flags = acpi_gpio_to_gpiod_flags(agpio);
536 lookup->info.polarity = lookup->active_low;
537 }
538 }
539
540 return 1;
541 }
542
543 static int acpi_gpio_resource_lookup(struct acpi_gpio_lookup *lookup,
544 struct acpi_gpio_info *info)
545 {
546 struct acpi_device *adev = lookup->info.adev;
547 struct list_head res_list;
548 int ret;
549
550 INIT_LIST_HEAD(&res_list);
551
552 ret = acpi_dev_get_resources(adev, &res_list,
553 acpi_populate_gpio_lookup,
554 lookup);
555 if (ret < 0)
556 return ret;
557
558 acpi_dev_free_resource_list(&res_list);
559
560 if (!lookup->desc)
561 return -ENOENT;
562
563 if (info)
564 *info = lookup->info;
565 return 0;
566 }
567
568 static int acpi_gpio_property_lookup(struct fwnode_handle *fwnode,
569 const char *propname, int index,
570 struct acpi_gpio_lookup *lookup)
571 {
572 struct fwnode_reference_args args;
573 unsigned int quirks = 0;
574 int ret;
575
576 memset(&args, 0, sizeof(args));
577 ret = __acpi_node_get_property_reference(fwnode, propname, index, 3,
578 &args);
579 if (ret) {
580 struct acpi_device *adev = to_acpi_device_node(fwnode);
581
582 if (!adev)
583 return ret;
584
585 if (!acpi_get_driver_gpio_data(adev, propname, index, &args,
586 &quirks))
587 return ret;
588 }
589 /*
590 * The property was found and resolved, so need to lookup the GPIO based
591 * on returned args.
592 */
593 if (!to_acpi_device_node(args.fwnode))
594 return -EINVAL;
595 if (args.nargs != 3)
596 return -EPROTO;
597
598 lookup->index = args.args[0];
599 lookup->pin_index = args.args[1];
600 lookup->active_low = !!args.args[2];
601
602 lookup->info.adev = to_acpi_device_node(args.fwnode);
603 lookup->info.quirks = quirks;
604
605 return 0;
606 }
607
608 /**
609 * acpi_get_gpiod_by_index() - get a GPIO descriptor from device resources
610 * @adev: pointer to a ACPI device to get GPIO from
611 * @propname: Property name of the GPIO (optional)
612 * @index: index of GpioIo/GpioInt resource (starting from %0)
613 * @info: info pointer to fill in (optional)
614 *
615 * Function goes through ACPI resources for @adev and based on @index looks
616 * up a GpioIo/GpioInt resource, translates it to the Linux GPIO descriptor,
617 * and returns it. @index matches GpioIo/GpioInt resources only so if there
618 * are total %3 GPIO resources, the index goes from %0 to %2.
619 *
620 * If @propname is specified the GPIO is looked using device property. In
621 * that case @index is used to select the GPIO entry in the property value
622 * (in case of multiple).
623 *
624 * If the GPIO cannot be translated or there is an error an ERR_PTR is
625 * returned.
626 *
627 * Note: if the GPIO resource has multiple entries in the pin list, this
628 * function only returns the first.
629 */
630 static struct gpio_desc *acpi_get_gpiod_by_index(struct acpi_device *adev,
631 const char *propname, int index,
632 struct acpi_gpio_info *info)
633 {
634 struct acpi_gpio_lookup lookup;
635 int ret;
636
637 if (!adev)
638 return ERR_PTR(-ENODEV);
639
640 memset(&lookup, 0, sizeof(lookup));
641 lookup.index = index;
642
643 if (propname) {
644 dev_dbg(&adev->dev, "GPIO: looking up %s\n", propname);
645
646 ret = acpi_gpio_property_lookup(acpi_fwnode_handle(adev),
647 propname, index, &lookup);
648 if (ret)
649 return ERR_PTR(ret);
650
651 dev_dbg(&adev->dev, "GPIO: _DSD returned %s %d %d %u\n",
652 dev_name(&lookup.info.adev->dev), lookup.index,
653 lookup.pin_index, lookup.active_low);
654 } else {
655 dev_dbg(&adev->dev, "GPIO: looking up %d in _CRS\n", index);
656 lookup.info.adev = adev;
657 }
658
659 ret = acpi_gpio_resource_lookup(&lookup, info);
660 return ret ? ERR_PTR(ret) : lookup.desc;
661 }
662
663 struct gpio_desc *acpi_find_gpio(struct device *dev,
664 const char *con_id,
665 unsigned int idx,
666 enum gpiod_flags *dflags,
667 enum gpio_lookup_flags *lookupflags)
668 {
669 struct acpi_device *adev = ACPI_COMPANION(dev);
670 struct acpi_gpio_info info;
671 struct gpio_desc *desc;
672 char propname[32];
673 int i;
674
675 /* Try first from _DSD */
676 for (i = 0; i < ARRAY_SIZE(gpio_suffixes); i++) {
677 if (con_id) {
678 snprintf(propname, sizeof(propname), "%s-%s",
679 con_id, gpio_suffixes[i]);
680 } else {
681 snprintf(propname, sizeof(propname), "%s",
682 gpio_suffixes[i]);
683 }
684
685 desc = acpi_get_gpiod_by_index(adev, propname, idx, &info);
686 if (!IS_ERR(desc))
687 break;
688 if (PTR_ERR(desc) == -EPROBE_DEFER)
689 return ERR_CAST(desc);
690 }
691
692 /* Then from plain _CRS GPIOs */
693 if (IS_ERR(desc)) {
694 if (!acpi_can_fallback_to_crs(adev, con_id))
695 return ERR_PTR(-ENOENT);
696
697 desc = acpi_get_gpiod_by_index(adev, NULL, idx, &info);
698 if (IS_ERR(desc))
699 return desc;
700 }
701
702 if (info.gpioint &&
703 (*dflags == GPIOD_OUT_LOW || *dflags == GPIOD_OUT_HIGH)) {
704 dev_dbg(dev, "refusing GpioInt() entry when doing GPIOD_OUT_* lookup\n");
705 return ERR_PTR(-ENOENT);
706 }
707
708 if (info.polarity == GPIO_ACTIVE_LOW)
709 *lookupflags |= GPIO_ACTIVE_LOW;
710
711 acpi_gpio_update_gpiod_flags(dflags, &info);
712 return desc;
713 }
714
715 /**
716 * acpi_node_get_gpiod() - get a GPIO descriptor from ACPI resources
717 * @fwnode: pointer to an ACPI firmware node to get the GPIO information from
718 * @propname: Property name of the GPIO
719 * @index: index of GpioIo/GpioInt resource (starting from %0)
720 * @info: info pointer to fill in (optional)
721 *
722 * If @fwnode is an ACPI device object, call %acpi_get_gpiod_by_index() for it.
723 * Otherwise (ie. it is a data-only non-device object), use the property-based
724 * GPIO lookup to get to the GPIO resource with the relevant information and use
725 * that to obtain the GPIO descriptor to return.
726 */
727 struct gpio_desc *acpi_node_get_gpiod(struct fwnode_handle *fwnode,
728 const char *propname, int index,
729 struct acpi_gpio_info *info)
730 {
731 struct acpi_gpio_lookup lookup;
732 struct acpi_device *adev;
733 int ret;
734
735 adev = to_acpi_device_node(fwnode);
736 if (adev)
737 return acpi_get_gpiod_by_index(adev, propname, index, info);
738
739 if (!is_acpi_data_node(fwnode))
740 return ERR_PTR(-ENODEV);
741
742 if (!propname)
743 return ERR_PTR(-EINVAL);
744
745 memset(&lookup, 0, sizeof(lookup));
746 lookup.index = index;
747
748 ret = acpi_gpio_property_lookup(fwnode, propname, index, &lookup);
749 if (ret)
750 return ERR_PTR(ret);
751
752 ret = acpi_gpio_resource_lookup(&lookup, info);
753 return ret ? ERR_PTR(ret) : lookup.desc;
754 }
755
756 /**
757 * acpi_dev_gpio_irq_get() - Find GpioInt and translate it to Linux IRQ number
758 * @adev: pointer to a ACPI device to get IRQ from
759 * @index: index of GpioInt resource (starting from %0)
760 *
761 * If the device has one or more GpioInt resources, this function can be
762 * used to translate from the GPIO offset in the resource to the Linux IRQ
763 * number.
764 *
765 * The function is idempotent, though each time it runs it will configure GPIO
766 * pin direction according to the flags in GpioInt resource.
767 *
768 * Return: Linux IRQ number (> %0) on success, negative errno on failure.
769 */
770 int acpi_dev_gpio_irq_get(struct acpi_device *adev, int index)
771 {
772 int idx, i;
773 unsigned int irq_flags;
774 int ret;
775
776 for (i = 0, idx = 0; idx <= index; i++) {
777 struct acpi_gpio_info info;
778 struct gpio_desc *desc;
779
780 desc = acpi_get_gpiod_by_index(adev, NULL, i, &info);
781
782 /* Ignore -EPROBE_DEFER, it only matters if idx matches */
783 if (IS_ERR(desc) && PTR_ERR(desc) != -EPROBE_DEFER)
784 return PTR_ERR(desc);
785
786 if (info.gpioint && idx++ == index) {
787 char label[32];
788 int irq;
789
790 if (IS_ERR(desc))
791 return PTR_ERR(desc);
792
793 irq = gpiod_to_irq(desc);
794 if (irq < 0)
795 return irq;
796
797 snprintf(label, sizeof(label), "GpioInt() %d", index);
798 ret = gpiod_configure_flags(desc, label, 0, info.flags);
799 if (ret < 0)
800 return ret;
801
802 irq_flags = acpi_dev_get_irq_type(info.triggering,
803 info.polarity);
804
805 /* Set type if specified and different than the current one */
806 if (irq_flags != IRQ_TYPE_NONE &&
807 irq_flags != irq_get_trigger_type(irq))
808 irq_set_irq_type(irq, irq_flags);
809
810 return irq;
811 }
812
813 }
814 return -ENOENT;
815 }
816 EXPORT_SYMBOL_GPL(acpi_dev_gpio_irq_get);
817
818 static acpi_status
819 acpi_gpio_adr_space_handler(u32 function, acpi_physical_address address,
820 u32 bits, u64 *value, void *handler_context,
821 void *region_context)
822 {
823 struct acpi_gpio_chip *achip = region_context;
824 struct gpio_chip *chip = achip->chip;
825 struct acpi_resource_gpio *agpio;
826 struct acpi_resource *ares;
827 int pin_index = (int)address;
828 acpi_status status;
829 int length;
830 int i;
831
832 status = acpi_buffer_to_resource(achip->conn_info.connection,
833 achip->conn_info.length, &ares);
834 if (ACPI_FAILURE(status))
835 return status;
836
837 if (WARN_ON(ares->type != ACPI_RESOURCE_TYPE_GPIO)) {
838 ACPI_FREE(ares);
839 return AE_BAD_PARAMETER;
840 }
841
842 agpio = &ares->data.gpio;
843
844 if (WARN_ON(agpio->io_restriction == ACPI_IO_RESTRICT_INPUT &&
845 function == ACPI_WRITE)) {
846 ACPI_FREE(ares);
847 return AE_BAD_PARAMETER;
848 }
849
850 length = min(agpio->pin_table_length, (u16)(pin_index + bits));
851 for (i = pin_index; i < length; ++i) {
852 int pin = agpio->pin_table[i];
853 struct acpi_gpio_connection *conn;
854 struct gpio_desc *desc;
855 bool found;
856
857 mutex_lock(&achip->conn_lock);
858
859 found = false;
860 list_for_each_entry(conn, &achip->conns, node) {
861 if (conn->pin == pin) {
862 found = true;
863 desc = conn->desc;
864 break;
865 }
866 }
867
868 /*
869 * The same GPIO can be shared between operation region and
870 * event but only if the access here is ACPI_READ. In that
871 * case we "borrow" the event GPIO instead.
872 */
873 if (!found && agpio->sharable == ACPI_SHARED &&
874 function == ACPI_READ) {
875 struct acpi_gpio_event *event;
876
877 list_for_each_entry(event, &achip->events, node) {
878 if (event->pin == pin) {
879 desc = event->desc;
880 found = true;
881 break;
882 }
883 }
884 }
885
886 if (!found) {
887 enum gpiod_flags flags = acpi_gpio_to_gpiod_flags(agpio);
888 const char *label = "ACPI:OpRegion";
889 int err;
890
891 desc = gpiochip_request_own_desc(chip, pin, label);
892 if (IS_ERR(desc)) {
893 status = AE_ERROR;
894 mutex_unlock(&achip->conn_lock);
895 goto out;
896 }
897
898 err = gpiod_configure_flags(desc, label, 0, flags);
899 if (err < 0) {
900 status = AE_NOT_CONFIGURED;
901 gpiochip_free_own_desc(desc);
902 mutex_unlock(&achip->conn_lock);
903 goto out;
904 }
905
906 conn = kzalloc(sizeof(*conn), GFP_KERNEL);
907 if (!conn) {
908 status = AE_NO_MEMORY;
909 gpiochip_free_own_desc(desc);
910 mutex_unlock(&achip->conn_lock);
911 goto out;
912 }
913
914 conn->pin = pin;
915 conn->desc = desc;
916 list_add_tail(&conn->node, &achip->conns);
917 }
918
919 mutex_unlock(&achip->conn_lock);
920
921 if (function == ACPI_WRITE)
922 gpiod_set_raw_value_cansleep(desc,
923 !!((1 << i) & *value));
924 else
925 *value |= (u64)gpiod_get_raw_value_cansleep(desc) << i;
926 }
927
928 out:
929 ACPI_FREE(ares);
930 return status;
931 }
932
933 static void acpi_gpiochip_request_regions(struct acpi_gpio_chip *achip)
934 {
935 struct gpio_chip *chip = achip->chip;
936 acpi_handle handle = ACPI_HANDLE(chip->parent);
937 acpi_status status;
938
939 INIT_LIST_HEAD(&achip->conns);
940 mutex_init(&achip->conn_lock);
941 status = acpi_install_address_space_handler(handle, ACPI_ADR_SPACE_GPIO,
942 acpi_gpio_adr_space_handler,
943 NULL, achip);
944 if (ACPI_FAILURE(status))
945 dev_err(chip->parent,
946 "Failed to install GPIO OpRegion handler\n");
947 }
948
949 static void acpi_gpiochip_free_regions(struct acpi_gpio_chip *achip)
950 {
951 struct gpio_chip *chip = achip->chip;
952 acpi_handle handle = ACPI_HANDLE(chip->parent);
953 struct acpi_gpio_connection *conn, *tmp;
954 acpi_status status;
955
956 status = acpi_remove_address_space_handler(handle, ACPI_ADR_SPACE_GPIO,
957 acpi_gpio_adr_space_handler);
958 if (ACPI_FAILURE(status)) {
959 dev_err(chip->parent,
960 "Failed to remove GPIO OpRegion handler\n");
961 return;
962 }
963
964 list_for_each_entry_safe_reverse(conn, tmp, &achip->conns, node) {
965 gpiochip_free_own_desc(conn->desc);
966 list_del(&conn->node);
967 kfree(conn);
968 }
969 }
970
971 static struct gpio_desc *acpi_gpiochip_parse_own_gpio(
972 struct acpi_gpio_chip *achip, struct fwnode_handle *fwnode,
973 const char **name, unsigned int *lflags, unsigned int *dflags)
974 {
975 struct gpio_chip *chip = achip->chip;
976 struct gpio_desc *desc;
977 u32 gpios[2];
978 int ret;
979
980 *lflags = 0;
981 *dflags = 0;
982 *name = NULL;
983
984 ret = fwnode_property_read_u32_array(fwnode, "gpios", gpios,
985 ARRAY_SIZE(gpios));
986 if (ret < 0)
987 return ERR_PTR(ret);
988
989 desc = gpiochip_get_desc(chip, gpios[0]);
990 if (IS_ERR(desc))
991 return desc;
992
993 if (gpios[1])
994 *lflags |= GPIO_ACTIVE_LOW;
995
996 if (fwnode_property_present(fwnode, "input"))
997 *dflags |= GPIOD_IN;
998 else if (fwnode_property_present(fwnode, "output-low"))
999 *dflags |= GPIOD_OUT_LOW;
1000 else if (fwnode_property_present(fwnode, "output-high"))
1001 *dflags |= GPIOD_OUT_HIGH;
1002 else
1003 return ERR_PTR(-EINVAL);
1004
1005 fwnode_property_read_string(fwnode, "line-name", name);
1006
1007 return desc;
1008 }
1009
1010 static void acpi_gpiochip_scan_gpios(struct acpi_gpio_chip *achip)
1011 {
1012 struct gpio_chip *chip = achip->chip;
1013 struct fwnode_handle *fwnode;
1014
1015 device_for_each_child_node(chip->parent, fwnode) {
1016 unsigned int lflags, dflags;
1017 struct gpio_desc *desc;
1018 const char *name;
1019 int ret;
1020
1021 if (!fwnode_property_present(fwnode, "gpio-hog"))
1022 continue;
1023
1024 desc = acpi_gpiochip_parse_own_gpio(achip, fwnode, &name,
1025 &lflags, &dflags);
1026 if (IS_ERR(desc))
1027 continue;
1028
1029 ret = gpiod_hog(desc, name, lflags, dflags);
1030 if (ret) {
1031 dev_err(chip->parent, "Failed to hog GPIO\n");
1032 fwnode_handle_put(fwnode);
1033 return;
1034 }
1035 }
1036 }
1037
1038 void acpi_gpiochip_add(struct gpio_chip *chip)
1039 {
1040 struct acpi_gpio_chip *acpi_gpio;
1041 acpi_handle handle;
1042 acpi_status status;
1043
1044 if (!chip || !chip->parent)
1045 return;
1046
1047 handle = ACPI_HANDLE(chip->parent);
1048 if (!handle)
1049 return;
1050
1051 acpi_gpio = kzalloc(sizeof(*acpi_gpio), GFP_KERNEL);
1052 if (!acpi_gpio) {
1053 dev_err(chip->parent,
1054 "Failed to allocate memory for ACPI GPIO chip\n");
1055 return;
1056 }
1057
1058 acpi_gpio->chip = chip;
1059 INIT_LIST_HEAD(&acpi_gpio->events);
1060 INIT_LIST_HEAD(&acpi_gpio->deferred_req_irqs_list_entry);
1061
1062 status = acpi_attach_data(handle, acpi_gpio_chip_dh, acpi_gpio);
1063 if (ACPI_FAILURE(status)) {
1064 dev_err(chip->parent, "Failed to attach ACPI GPIO chip\n");
1065 kfree(acpi_gpio);
1066 return;
1067 }
1068
1069 if (!chip->names)
1070 devprop_gpiochip_set_names(chip, dev_fwnode(chip->parent));
1071
1072 acpi_gpiochip_request_regions(acpi_gpio);
1073 acpi_gpiochip_scan_gpios(acpi_gpio);
1074 acpi_walk_dep_device_list(handle);
1075 }
1076
1077 void acpi_gpiochip_remove(struct gpio_chip *chip)
1078 {
1079 struct acpi_gpio_chip *acpi_gpio;
1080 acpi_handle handle;
1081 acpi_status status;
1082
1083 if (!chip || !chip->parent)
1084 return;
1085
1086 handle = ACPI_HANDLE(chip->parent);
1087 if (!handle)
1088 return;
1089
1090 status = acpi_get_data(handle, acpi_gpio_chip_dh, (void **)&acpi_gpio);
1091 if (ACPI_FAILURE(status)) {
1092 dev_warn(chip->parent, "Failed to retrieve ACPI GPIO chip\n");
1093 return;
1094 }
1095
1096 acpi_gpiochip_free_regions(acpi_gpio);
1097
1098 acpi_detach_data(handle, acpi_gpio_chip_dh);
1099 kfree(acpi_gpio);
1100 }
1101
1102 static int acpi_gpio_package_count(const union acpi_object *obj)
1103 {
1104 const union acpi_object *element = obj->package.elements;
1105 const union acpi_object *end = element + obj->package.count;
1106 unsigned int count = 0;
1107
1108 while (element < end) {
1109 switch (element->type) {
1110 case ACPI_TYPE_LOCAL_REFERENCE:
1111 element += 3;
1112 /* Fallthrough */
1113 case ACPI_TYPE_INTEGER:
1114 element++;
1115 count++;
1116 break;
1117
1118 default:
1119 return -EPROTO;
1120 }
1121 }
1122
1123 return count;
1124 }
1125
1126 static int acpi_find_gpio_count(struct acpi_resource *ares, void *data)
1127 {
1128 unsigned int *count = data;
1129
1130 if (ares->type == ACPI_RESOURCE_TYPE_GPIO)
1131 *count += ares->data.gpio.pin_table_length;
1132
1133 return 1;
1134 }
1135
1136 /**
1137 * acpi_gpio_count - return the number of GPIOs associated with a
1138 * device / function or -ENOENT if no GPIO has been
1139 * assigned to the requested function.
1140 * @dev: GPIO consumer, can be NULL for system-global GPIOs
1141 * @con_id: function within the GPIO consumer
1142 */
1143 int acpi_gpio_count(struct device *dev, const char *con_id)
1144 {
1145 struct acpi_device *adev = ACPI_COMPANION(dev);
1146 const union acpi_object *obj;
1147 const struct acpi_gpio_mapping *gm;
1148 int count = -ENOENT;
1149 int ret;
1150 char propname[32];
1151 unsigned int i;
1152
1153 /* Try first from _DSD */
1154 for (i = 0; i < ARRAY_SIZE(gpio_suffixes); i++) {
1155 if (con_id)
1156 snprintf(propname, sizeof(propname), "%s-%s",
1157 con_id, gpio_suffixes[i]);
1158 else
1159 snprintf(propname, sizeof(propname), "%s",
1160 gpio_suffixes[i]);
1161
1162 ret = acpi_dev_get_property(adev, propname, ACPI_TYPE_ANY,
1163 &obj);
1164 if (ret == 0) {
1165 if (obj->type == ACPI_TYPE_LOCAL_REFERENCE)
1166 count = 1;
1167 else if (obj->type == ACPI_TYPE_PACKAGE)
1168 count = acpi_gpio_package_count(obj);
1169 } else if (adev->driver_gpios) {
1170 for (gm = adev->driver_gpios; gm->name; gm++)
1171 if (strcmp(propname, gm->name) == 0) {
1172 count = gm->size;
1173 break;
1174 }
1175 }
1176 if (count > 0)
1177 break;
1178 }
1179
1180 /* Then from plain _CRS GPIOs */
1181 if (count < 0) {
1182 struct list_head resource_list;
1183 unsigned int crs_count = 0;
1184
1185 if (!acpi_can_fallback_to_crs(adev, con_id))
1186 return count;
1187
1188 INIT_LIST_HEAD(&resource_list);
1189 acpi_dev_get_resources(adev, &resource_list,
1190 acpi_find_gpio_count, &crs_count);
1191 acpi_dev_free_resource_list(&resource_list);
1192 if (crs_count > 0)
1193 count = crs_count;
1194 }
1195 return count ? count : -ENOENT;
1196 }
1197
1198 bool acpi_can_fallback_to_crs(struct acpi_device *adev, const char *con_id)
1199 {
1200 /* Never allow fallback if the device has properties */
1201 if (adev->data.properties || adev->driver_gpios)
1202 return false;
1203
1204 return con_id == NULL;
1205 }
1206
1207 /* Run deferred acpi_gpiochip_request_interrupts() */
1208 static int acpi_gpio_handle_deferred_request_interrupts(void)
1209 {
1210 struct acpi_gpio_chip *acpi_gpio, *tmp;
1211
1212 mutex_lock(&acpi_gpio_deferred_req_irqs_lock);
1213 list_for_each_entry_safe(acpi_gpio, tmp,
1214 &acpi_gpio_deferred_req_irqs_list,
1215 deferred_req_irqs_list_entry) {
1216 acpi_handle handle;
1217
1218 handle = ACPI_HANDLE(acpi_gpio->chip->parent);
1219 acpi_walk_resources(handle, "_AEI",
1220 acpi_gpiochip_request_interrupt, acpi_gpio);
1221
1222 list_del_init(&acpi_gpio->deferred_req_irqs_list_entry);
1223 }
1224
1225 acpi_gpio_deferred_req_irqs_done = true;
1226 mutex_unlock(&acpi_gpio_deferred_req_irqs_lock);
1227
1228 return 0;
1229 }
1230 /* We must use _sync so that this runs after the first deferred_probe run */
1231 late_initcall_sync(acpi_gpio_handle_deferred_request_interrupts);
Linux with added FPC-III support