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perf tools: Don't clone maps from parent when synthesizing forks
[linux/fpc-iii.git] / drivers / gpio / gpiolib-acpi.c
blob55b72fbe163169c29766fbb6e24f58ccfdfd62c2
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * ACPI helpers for GPIO API
4 *
5 * Copyright (C) 2012, Intel Corporation
6 * Authors: Mathias Nyman <mathias.nyman@linux.intel.com>
7 * Mika Westerberg <mika.westerberg@linux.intel.com>
8 */
9
10 #include <linux/errno.h>
11 #include <linux/gpio/consumer.h>
12 #include <linux/gpio/driver.h>
13 #include <linux/gpio/machine.h>
14 #include <linux/export.h>
15 #include <linux/acpi.h>
16 #include <linux/interrupt.h>
17 #include <linux/mutex.h>
18 #include <linux/pinctrl/pinctrl.h>
19
20 #include "gpiolib.h"
21
22 struct acpi_gpio_event {
23 struct list_head node;
24 acpi_handle handle;
25 unsigned int pin;
26 unsigned int irq;
27 struct gpio_desc *desc;
28 };
29
30 struct acpi_gpio_connection {
31 struct list_head node;
32 unsigned int pin;
33 struct gpio_desc *desc;
34 };
35
36 struct acpi_gpio_chip {
37 /*
38 * ACPICA requires that the first field of the context parameter
39 * passed to acpi_install_address_space_handler() is large enough
40 * to hold struct acpi_connection_info.
41 */
42 struct acpi_connection_info conn_info;
43 struct list_head conns;
44 struct mutex conn_lock;
45 struct gpio_chip *chip;
46 struct list_head events;
47 struct list_head deferred_req_irqs_list_entry;
48 };
49
50 /*
51 * For gpiochips which call acpi_gpiochip_request_interrupts() before late_init
52 * (so builtin drivers) we register the ACPI GpioInt event handlers from a
53 * late_initcall_sync handler, so that other builtin drivers can register their
54 * OpRegions before the event handlers can run. This list contains gpiochips
55 * for which the acpi_gpiochip_request_interrupts() has been deferred.
56 */
57 static DEFINE_MUTEX(acpi_gpio_deferred_req_irqs_lock);
58 static LIST_HEAD(acpi_gpio_deferred_req_irqs_list);
59 static bool acpi_gpio_deferred_req_irqs_done;
60
61 static int acpi_gpiochip_find(struct gpio_chip *gc, void *data)
62 {
63 if (!gc->parent)
64 return false;
65
66 return ACPI_HANDLE(gc->parent) == data;
67 }
68
69 /**
70 * acpi_get_gpiod() - Translate ACPI GPIO pin to GPIO descriptor usable with GPIO API
71 * @path: ACPI GPIO controller full path name, (e.g. "\\_SB.GPO1")
72 * @pin: ACPI GPIO pin number (0-based, controller-relative)
73 *
74 * Return: GPIO descriptor to use with Linux generic GPIO API, or ERR_PTR
75 * error value. Specifically returns %-EPROBE_DEFER if the referenced GPIO
76 * controller does not have gpiochip registered at the moment. This is to
77 * support probe deferral.
78 */
79 static struct gpio_desc *acpi_get_gpiod(char *path, int pin)
80 {
81 struct gpio_chip *chip;
82 acpi_handle handle;
83 acpi_status status;
84
85 status = acpi_get_handle(NULL, path, &handle);
86 if (ACPI_FAILURE(status))
87 return ERR_PTR(-ENODEV);
88
89 chip = gpiochip_find(handle, acpi_gpiochip_find);
90 if (!chip)
91 return ERR_PTR(-EPROBE_DEFER);
92
93 return gpiochip_get_desc(chip, pin);
94 }
95
96 static irqreturn_t acpi_gpio_irq_handler(int irq, void *data)
97 {
98 struct acpi_gpio_event *event = data;
99
100 acpi_evaluate_object(event->handle, NULL, NULL, NULL);
101
102 return IRQ_HANDLED;
103 }
104
105 static irqreturn_t acpi_gpio_irq_handler_evt(int irq, void *data)
106 {
107 struct acpi_gpio_event *event = data;
108
109 acpi_execute_simple_method(event->handle, NULL, event->pin);
110
111 return IRQ_HANDLED;
112 }
113
114 static void acpi_gpio_chip_dh(acpi_handle handle, void *data)
115 {
116 /* The address of this function is used as a key. */
117 }
118
119 bool acpi_gpio_get_irq_resource(struct acpi_resource *ares,
120 struct acpi_resource_gpio **agpio)
121 {
122 struct acpi_resource_gpio *gpio;
123
124 if (ares->type != ACPI_RESOURCE_TYPE_GPIO)
125 return false;
126
127 gpio = &ares->data.gpio;
128 if (gpio->connection_type != ACPI_RESOURCE_GPIO_TYPE_INT)
129 return false;
130
131 *agpio = gpio;
132 return true;
133 }
134 EXPORT_SYMBOL_GPL(acpi_gpio_get_irq_resource);
135
136 static acpi_status acpi_gpiochip_request_interrupt(struct acpi_resource *ares,
137 void *context)
138 {
139 struct acpi_gpio_chip *acpi_gpio = context;
140 struct gpio_chip *chip = acpi_gpio->chip;
141 struct acpi_resource_gpio *agpio;
142 acpi_handle handle, evt_handle;
143 struct acpi_gpio_event *event;
144 irq_handler_t handler = NULL;
145 struct gpio_desc *desc;
146 unsigned long irqflags;
147 int ret, pin, irq, value;
148
149 if (!acpi_gpio_get_irq_resource(ares, &agpio))
150 return AE_OK;
151
152 handle = ACPI_HANDLE(chip->parent);
153 pin = agpio->pin_table[0];
154
155 if (pin <= 255) {
156 char ev_name[5];
157 sprintf(ev_name, "_%c%02hhX",
158 agpio->triggering == ACPI_EDGE_SENSITIVE ? 'E' : 'L',
159 pin);
160 if (ACPI_SUCCESS(acpi_get_handle(handle, ev_name, &evt_handle)))
161 handler = acpi_gpio_irq_handler;
162 }
163 if (!handler) {
164 if (ACPI_SUCCESS(acpi_get_handle(handle, "_EVT", &evt_handle)))
165 handler = acpi_gpio_irq_handler_evt;
166 }
167 if (!handler)
168 return AE_OK;
169
170 desc = gpiochip_request_own_desc(chip, pin, "ACPI:Event");
171 if (IS_ERR(desc)) {
172 dev_err(chip->parent, "Failed to request GPIO\n");
173 return AE_ERROR;
174 }
175
176 gpiod_direction_input(desc);
177
178 value = gpiod_get_value_cansleep(desc);
179
180 ret = gpiochip_lock_as_irq(chip, pin);
181 if (ret) {
182 dev_err(chip->parent, "Failed to lock GPIO as interrupt\n");
183 goto fail_free_desc;
184 }
185
186 irq = gpiod_to_irq(desc);
187 if (irq < 0) {
188 dev_err(chip->parent, "Failed to translate GPIO to IRQ\n");
189 goto fail_unlock_irq;
190 }
191
192 irqflags = IRQF_ONESHOT;
193 if (agpio->triggering == ACPI_LEVEL_SENSITIVE) {
194 if (agpio->polarity == ACPI_ACTIVE_HIGH)
195 irqflags |= IRQF_TRIGGER_HIGH;
196 else
197 irqflags |= IRQF_TRIGGER_LOW;
198 } else {
199 switch (agpio->polarity) {
200 case ACPI_ACTIVE_HIGH:
201 irqflags |= IRQF_TRIGGER_RISING;
202 break;
203 case ACPI_ACTIVE_LOW:
204 irqflags |= IRQF_TRIGGER_FALLING;
205 break;
206 default:
207 irqflags |= IRQF_TRIGGER_RISING |
208 IRQF_TRIGGER_FALLING;
209 break;
210 }
211 }
212
213 event = kzalloc(sizeof(*event), GFP_KERNEL);
214 if (!event)
215 goto fail_unlock_irq;
216
217 event->handle = evt_handle;
218 event->irq = irq;
219 event->pin = pin;
220 event->desc = desc;
221
222 ret = request_threaded_irq(event->irq, NULL, handler, irqflags,
223 "ACPI:Event", event);
224 if (ret) {
225 dev_err(chip->parent,
226 "Failed to setup interrupt handler for %d\n",
227 event->irq);
228 goto fail_free_event;
229 }
230
231 if (agpio->wake_capable == ACPI_WAKE_CAPABLE)
232 enable_irq_wake(irq);
233
234 list_add_tail(&event->node, &acpi_gpio->events);
235
236 /*
237 * Make sure we trigger the initial state of the IRQ when using RISING
238 * or FALLING. Note we run the handlers on late_init, the AML code
239 * may refer to OperationRegions from other (builtin) drivers which
240 * may be probed after us.
241 */
242 if (((irqflags & IRQF_TRIGGER_RISING) && value == 1) ||
243 ((irqflags & IRQF_TRIGGER_FALLING) && value == 0))
244 handler(event->irq, event);
245
246 return AE_OK;
247
248 fail_free_event:
249 kfree(event);
250 fail_unlock_irq:
251 gpiochip_unlock_as_irq(chip, pin);
252 fail_free_desc:
253 gpiochip_free_own_desc(desc);
254
255 return AE_ERROR;
256 }
257
258 /**
259 * acpi_gpiochip_request_interrupts() - Register isr for gpio chip ACPI events
260 * @chip: GPIO chip
261 *
262 * ACPI5 platforms can use GPIO signaled ACPI events. These GPIO interrupts are
263 * handled by ACPI event methods which need to be called from the GPIO
264 * chip's interrupt handler. acpi_gpiochip_request_interrupts finds out which
265 * gpio pins have acpi event methods and assigns interrupt handlers that calls
266 * the acpi event methods for those pins.
267 */
268 void acpi_gpiochip_request_interrupts(struct gpio_chip *chip)
269 {
270 struct acpi_gpio_chip *acpi_gpio;
271 acpi_handle handle;
272 acpi_status status;
273 bool defer;
274
275 if (!chip->parent || !chip->to_irq)
276 return;
277
278 handle = ACPI_HANDLE(chip->parent);
279 if (!handle)
280 return;
281
282 status = acpi_get_data(handle, acpi_gpio_chip_dh, (void **)&acpi_gpio);
283 if (ACPI_FAILURE(status))
284 return;
285
286 mutex_lock(&acpi_gpio_deferred_req_irqs_lock);
287 defer = !acpi_gpio_deferred_req_irqs_done;
288 if (defer)
289 list_add(&acpi_gpio->deferred_req_irqs_list_entry,
290 &acpi_gpio_deferred_req_irqs_list);
291 mutex_unlock(&acpi_gpio_deferred_req_irqs_lock);
292
293 if (defer)
294 return;
295
296 acpi_walk_resources(handle, "_AEI",
297 acpi_gpiochip_request_interrupt, acpi_gpio);
298 }
299 EXPORT_SYMBOL_GPL(acpi_gpiochip_request_interrupts);
300
301 /**
302 * acpi_gpiochip_free_interrupts() - Free GPIO ACPI event interrupts.
303 * @chip: GPIO chip
304 *
305 * Free interrupts associated with GPIO ACPI event method for the given
306 * GPIO chip.
307 */
308 void acpi_gpiochip_free_interrupts(struct gpio_chip *chip)
309 {
310 struct acpi_gpio_chip *acpi_gpio;
311 struct acpi_gpio_event *event, *ep;
312 acpi_handle handle;
313 acpi_status status;
314
315 if (!chip->parent || !chip->to_irq)
316 return;
317
318 handle = ACPI_HANDLE(chip->parent);
319 if (!handle)
320 return;
321
322 status = acpi_get_data(handle, acpi_gpio_chip_dh, (void **)&acpi_gpio);
323 if (ACPI_FAILURE(status))
324 return;
325
326 mutex_lock(&acpi_gpio_deferred_req_irqs_lock);
327 if (!list_empty(&acpi_gpio->deferred_req_irqs_list_entry))
328 list_del_init(&acpi_gpio->deferred_req_irqs_list_entry);
329 mutex_unlock(&acpi_gpio_deferred_req_irqs_lock);
330
331 list_for_each_entry_safe_reverse(event, ep, &acpi_gpio->events, node) {
332 struct gpio_desc *desc;
333
334 if (irqd_is_wakeup_set(irq_get_irq_data(event->irq)))
335 disable_irq_wake(event->irq);
336
337 free_irq(event->irq, event);
338 desc = event->desc;
339 if (WARN_ON(IS_ERR(desc)))
340 continue;
341 gpiochip_unlock_as_irq(chip, event->pin);
342 gpiochip_free_own_desc(desc);
343 list_del(&event->node);
344 kfree(event);
345 }
346 }
347 EXPORT_SYMBOL_GPL(acpi_gpiochip_free_interrupts);
348
349 int acpi_dev_add_driver_gpios(struct acpi_device *adev,
350 const struct acpi_gpio_mapping *gpios)
351 {
352 if (adev && gpios) {
353 adev->driver_gpios = gpios;
354 return 0;
355 }
356 return -EINVAL;
357 }
358 EXPORT_SYMBOL_GPL(acpi_dev_add_driver_gpios);
359
360 static void devm_acpi_dev_release_driver_gpios(struct device *dev, void *res)
361 {
362 acpi_dev_remove_driver_gpios(ACPI_COMPANION(dev));
363 }
364
365 int devm_acpi_dev_add_driver_gpios(struct device *dev,
366 const struct acpi_gpio_mapping *gpios)
367 {
368 void *res;
369 int ret;
370
371 res = devres_alloc(devm_acpi_dev_release_driver_gpios, 0, GFP_KERNEL);
372 if (!res)
373 return -ENOMEM;
374
375 ret = acpi_dev_add_driver_gpios(ACPI_COMPANION(dev), gpios);
376 if (ret) {
377 devres_free(res);
378 return ret;
379 }
380 devres_add(dev, res);
381 return 0;
382 }
383 EXPORT_SYMBOL_GPL(devm_acpi_dev_add_driver_gpios);
384
385 void devm_acpi_dev_remove_driver_gpios(struct device *dev)
386 {
387 WARN_ON(devres_release(dev, devm_acpi_dev_release_driver_gpios, NULL, NULL));
388 }
389 EXPORT_SYMBOL_GPL(devm_acpi_dev_remove_driver_gpios);
390
391 static bool acpi_get_driver_gpio_data(struct acpi_device *adev,
392 const char *name, int index,
393 struct fwnode_reference_args *args,
394 unsigned int *quirks)
395 {
396 const struct acpi_gpio_mapping *gm;
397
398 if (!adev->driver_gpios)
399 return false;
400
401 for (gm = adev->driver_gpios; gm->name; gm++)
402 if (!strcmp(name, gm->name) && gm->data && index < gm->size) {
403 const struct acpi_gpio_params *par = gm->data + index;
404
405 args->fwnode = acpi_fwnode_handle(adev);
406 args->args[0] = par->crs_entry_index;
407 args->args[1] = par->line_index;
408 args->args[2] = par->active_low;
409 args->nargs = 3;
410
411 *quirks = gm->quirks;
412 return true;
413 }
414
415 return false;
416 }
417
418 static enum gpiod_flags
419 acpi_gpio_to_gpiod_flags(const struct acpi_resource_gpio *agpio)
420 {
421 bool pull_up = agpio->pin_config == ACPI_PIN_CONFIG_PULLUP;
422
423 switch (agpio->io_restriction) {
424 case ACPI_IO_RESTRICT_INPUT:
425 return GPIOD_IN;
426 case ACPI_IO_RESTRICT_OUTPUT:
427 /*
428 * ACPI GPIO resources don't contain an initial value for the
429 * GPIO. Therefore we deduce that value from the pull field
430 * instead. If the pin is pulled up we assume default to be
431 * high, otherwise low.
432 */
433 return pull_up ? GPIOD_OUT_HIGH : GPIOD_OUT_LOW;
434 default:
435 /*
436 * Assume that the BIOS has configured the direction and pull
437 * accordingly.
438 */
439 return GPIOD_ASIS;
440 }
441 }
442
443 static int
444 __acpi_gpio_update_gpiod_flags(enum gpiod_flags *flags, enum gpiod_flags update)
445 {
446 int ret = 0;
447
448 /*
449 * Check if the BIOS has IoRestriction with explicitly set direction
450 * and update @flags accordingly. Otherwise use whatever caller asked
451 * for.
452 */
453 if (update & GPIOD_FLAGS_BIT_DIR_SET) {
454 enum gpiod_flags diff = *flags ^ update;
455
456 /*
457 * Check if caller supplied incompatible GPIO initialization
458 * flags.
459 *
460 * Return %-EINVAL to notify that firmware has different
461 * settings and we are going to use them.
462 */
463 if (((*flags & GPIOD_FLAGS_BIT_DIR_SET) && (diff & GPIOD_FLAGS_BIT_DIR_OUT)) ||
464 ((*flags & GPIOD_FLAGS_BIT_DIR_OUT) && (diff & GPIOD_FLAGS_BIT_DIR_VAL)))
465 ret = -EINVAL;
466 *flags = update;
467 }
468 return ret;
469 }
470
471 int
472 acpi_gpio_update_gpiod_flags(enum gpiod_flags *flags, struct acpi_gpio_info *info)
473 {
474 struct device *dev = &info->adev->dev;
475 enum gpiod_flags old = *flags;
476 int ret;
477
478 ret = __acpi_gpio_update_gpiod_flags(&old, info->flags);
479 if (info->quirks & ACPI_GPIO_QUIRK_NO_IO_RESTRICTION) {
480 if (ret)
481 dev_warn(dev, FW_BUG "GPIO not in correct mode, fixing\n");
482 } else {
483 if (ret)
484 dev_dbg(dev, "Override GPIO initialization flags\n");
485 *flags = old;
486 }
487
488 return ret;
489 }
490
491 struct acpi_gpio_lookup {
492 struct acpi_gpio_info info;
493 int index;
494 int pin_index;
495 bool active_low;
496 struct gpio_desc *desc;
497 int n;
498 };
499
500 static int acpi_populate_gpio_lookup(struct acpi_resource *ares, void *data)
501 {
502 struct acpi_gpio_lookup *lookup = data;
503
504 if (ares->type != ACPI_RESOURCE_TYPE_GPIO)
505 return 1;
506
507 if (lookup->n++ == lookup->index && !lookup->desc) {
508 const struct acpi_resource_gpio *agpio = &ares->data.gpio;
509 int pin_index = lookup->pin_index;
510
511 if (pin_index >= agpio->pin_table_length)
512 return 1;
513
514 lookup->desc = acpi_get_gpiod(agpio->resource_source.string_ptr,
515 agpio->pin_table[pin_index]);
516 lookup->info.gpioint =
517 agpio->connection_type == ACPI_RESOURCE_GPIO_TYPE_INT;
518
519 /*
520 * Polarity and triggering are only specified for GpioInt
521 * resource.
522 * Note: we expect here:
523 * - ACPI_ACTIVE_LOW == GPIO_ACTIVE_LOW
524 * - ACPI_ACTIVE_HIGH == GPIO_ACTIVE_HIGH
525 */
526 if (lookup->info.gpioint) {
527 lookup->info.flags = GPIOD_IN;
528 lookup->info.polarity = agpio->polarity;
529 lookup->info.triggering = agpio->triggering;
530 } else {
531 lookup->info.flags = acpi_gpio_to_gpiod_flags(agpio);
532 lookup->info.polarity = lookup->active_low;
533 }
534 }
535
536 return 1;
537 }
538
539 static int acpi_gpio_resource_lookup(struct acpi_gpio_lookup *lookup,
540 struct acpi_gpio_info *info)
541 {
542 struct acpi_device *adev = lookup->info.adev;
543 struct list_head res_list;
544 int ret;
545
546 INIT_LIST_HEAD(&res_list);
547
548 ret = acpi_dev_get_resources(adev, &res_list,
549 acpi_populate_gpio_lookup,
550 lookup);
551 if (ret < 0)
552 return ret;
553
554 acpi_dev_free_resource_list(&res_list);
555
556 if (!lookup->desc)
557 return -ENOENT;
558
559 if (info)
560 *info = lookup->info;
561 return 0;
562 }
563
564 static int acpi_gpio_property_lookup(struct fwnode_handle *fwnode,
565 const char *propname, int index,
566 struct acpi_gpio_lookup *lookup)
567 {
568 struct fwnode_reference_args args;
569 unsigned int quirks = 0;
570 int ret;
571
572 memset(&args, 0, sizeof(args));
573 ret = __acpi_node_get_property_reference(fwnode, propname, index, 3,
574 &args);
575 if (ret) {
576 struct acpi_device *adev = to_acpi_device_node(fwnode);
577
578 if (!adev)
579 return ret;
580
581 if (!acpi_get_driver_gpio_data(adev, propname, index, &args,
582 &quirks))
583 return ret;
584 }
585 /*
586 * The property was found and resolved, so need to lookup the GPIO based
587 * on returned args.
588 */
589 if (!to_acpi_device_node(args.fwnode))
590 return -EINVAL;
591 if (args.nargs != 3)
592 return -EPROTO;
593
594 lookup->index = args.args[0];
595 lookup->pin_index = args.args[1];
596 lookup->active_low = !!args.args[2];
597
598 lookup->info.adev = to_acpi_device_node(args.fwnode);
599 lookup->info.quirks = quirks;
600
601 return 0;
602 }
603
604 /**
605 * acpi_get_gpiod_by_index() - get a GPIO descriptor from device resources
606 * @adev: pointer to a ACPI device to get GPIO from
607 * @propname: Property name of the GPIO (optional)
608 * @index: index of GpioIo/GpioInt resource (starting from %0)
609 * @info: info pointer to fill in (optional)
610 *
611 * Function goes through ACPI resources for @adev and based on @index looks
612 * up a GpioIo/GpioInt resource, translates it to the Linux GPIO descriptor,
613 * and returns it. @index matches GpioIo/GpioInt resources only so if there
614 * are total %3 GPIO resources, the index goes from %0 to %2.
615 *
616 * If @propname is specified the GPIO is looked using device property. In
617 * that case @index is used to select the GPIO entry in the property value
618 * (in case of multiple).
619 *
620 * If the GPIO cannot be translated or there is an error an ERR_PTR is
621 * returned.
622 *
623 * Note: if the GPIO resource has multiple entries in the pin list, this
624 * function only returns the first.
625 */
626 static struct gpio_desc *acpi_get_gpiod_by_index(struct acpi_device *adev,
627 const char *propname, int index,
628 struct acpi_gpio_info *info)
629 {
630 struct acpi_gpio_lookup lookup;
631 int ret;
632
633 if (!adev)
634 return ERR_PTR(-ENODEV);
635
636 memset(&lookup, 0, sizeof(lookup));
637 lookup.index = index;
638
639 if (propname) {
640 dev_dbg(&adev->dev, "GPIO: looking up %s\n", propname);
641
642 ret = acpi_gpio_property_lookup(acpi_fwnode_handle(adev),
643 propname, index, &lookup);
644 if (ret)
645 return ERR_PTR(ret);
646
647 dev_dbg(&adev->dev, "GPIO: _DSD returned %s %d %d %u\n",
648 dev_name(&lookup.info.adev->dev), lookup.index,
649 lookup.pin_index, lookup.active_low);
650 } else {
651 dev_dbg(&adev->dev, "GPIO: looking up %d in _CRS\n", index);
652 lookup.info.adev = adev;
653 }
654
655 ret = acpi_gpio_resource_lookup(&lookup, info);
656 return ret ? ERR_PTR(ret) : lookup.desc;
657 }
658
659 struct gpio_desc *acpi_find_gpio(struct device *dev,
660 const char *con_id,
661 unsigned int idx,
662 enum gpiod_flags *dflags,
663 enum gpio_lookup_flags *lookupflags)
664 {
665 struct acpi_device *adev = ACPI_COMPANION(dev);
666 struct acpi_gpio_info info;
667 struct gpio_desc *desc;
668 char propname[32];
669 int i;
670
671 /* Try first from _DSD */
672 for (i = 0; i < ARRAY_SIZE(gpio_suffixes); i++) {
673 if (con_id) {
674 snprintf(propname, sizeof(propname), "%s-%s",
675 con_id, gpio_suffixes[i]);
676 } else {
677 snprintf(propname, sizeof(propname), "%s",
678 gpio_suffixes[i]);
679 }
680
681 desc = acpi_get_gpiod_by_index(adev, propname, idx, &info);
682 if (!IS_ERR(desc))
683 break;
684 if (PTR_ERR(desc) == -EPROBE_DEFER)
685 return ERR_CAST(desc);
686 }
687
688 /* Then from plain _CRS GPIOs */
689 if (IS_ERR(desc)) {
690 if (!acpi_can_fallback_to_crs(adev, con_id))
691 return ERR_PTR(-ENOENT);
692
693 desc = acpi_get_gpiod_by_index(adev, NULL, idx, &info);
694 if (IS_ERR(desc))
695 return desc;
696 }
697
698 if (info.gpioint &&
699 (*dflags == GPIOD_OUT_LOW || *dflags == GPIOD_OUT_HIGH)) {
700 dev_dbg(dev, "refusing GpioInt() entry when doing GPIOD_OUT_* lookup\n");
701 return ERR_PTR(-ENOENT);
702 }
703
704 if (info.polarity == GPIO_ACTIVE_LOW)
705 *lookupflags |= GPIO_ACTIVE_LOW;
706
707 acpi_gpio_update_gpiod_flags(dflags, &info);
708 return desc;
709 }
710
711 /**
712 * acpi_node_get_gpiod() - get a GPIO descriptor from ACPI resources
713 * @fwnode: pointer to an ACPI firmware node to get the GPIO information from
714 * @propname: Property name of the GPIO
715 * @index: index of GpioIo/GpioInt resource (starting from %0)
716 * @info: info pointer to fill in (optional)
717 *
718 * If @fwnode is an ACPI device object, call %acpi_get_gpiod_by_index() for it.
719 * Otherwise (ie. it is a data-only non-device object), use the property-based
720 * GPIO lookup to get to the GPIO resource with the relevant information and use
721 * that to obtain the GPIO descriptor to return.
722 */
723 struct gpio_desc *acpi_node_get_gpiod(struct fwnode_handle *fwnode,
724 const char *propname, int index,
725 struct acpi_gpio_info *info)
726 {
727 struct acpi_gpio_lookup lookup;
728 struct acpi_device *adev;
729 int ret;
730
731 adev = to_acpi_device_node(fwnode);
732 if (adev)
733 return acpi_get_gpiod_by_index(adev, propname, index, info);
734
735 if (!is_acpi_data_node(fwnode))
736 return ERR_PTR(-ENODEV);
737
738 if (!propname)
739 return ERR_PTR(-EINVAL);
740
741 memset(&lookup, 0, sizeof(lookup));
742 lookup.index = index;
743
744 ret = acpi_gpio_property_lookup(fwnode, propname, index, &lookup);
745 if (ret)
746 return ERR_PTR(ret);
747
748 ret = acpi_gpio_resource_lookup(&lookup, info);
749 return ret ? ERR_PTR(ret) : lookup.desc;
750 }
751
752 /**
753 * acpi_dev_gpio_irq_get() - Find GpioInt and translate it to Linux IRQ number
754 * @adev: pointer to a ACPI device to get IRQ from
755 * @index: index of GpioInt resource (starting from %0)
756 *
757 * If the device has one or more GpioInt resources, this function can be
758 * used to translate from the GPIO offset in the resource to the Linux IRQ
759 * number.
760 *
761 * The function is idempotent, though each time it runs it will configure GPIO
762 * pin direction according to the flags in GpioInt resource.
763 *
764 * Return: Linux IRQ number (> %0) on success, negative errno on failure.
765 */
766 int acpi_dev_gpio_irq_get(struct acpi_device *adev, int index)
767 {
768 int idx, i;
769 unsigned int irq_flags;
770 int ret;
771
772 for (i = 0, idx = 0; idx <= index; i++) {
773 struct acpi_gpio_info info;
774 struct gpio_desc *desc;
775
776 desc = acpi_get_gpiod_by_index(adev, NULL, i, &info);
777
778 /* Ignore -EPROBE_DEFER, it only matters if idx matches */
779 if (IS_ERR(desc) && PTR_ERR(desc) != -EPROBE_DEFER)
780 return PTR_ERR(desc);
781
782 if (info.gpioint && idx++ == index) {
783 char label[32];
784 int irq;
785
786 if (IS_ERR(desc))
787 return PTR_ERR(desc);
788
789 irq = gpiod_to_irq(desc);
790 if (irq < 0)
791 return irq;
792
793 snprintf(label, sizeof(label), "GpioInt() %d", index);
794 ret = gpiod_configure_flags(desc, label, 0, info.flags);
795 if (ret < 0)
796 return ret;
797
798 irq_flags = acpi_dev_get_irq_type(info.triggering,
799 info.polarity);
800
801 /* Set type if specified and different than the current one */
802 if (irq_flags != IRQ_TYPE_NONE &&
803 irq_flags != irq_get_trigger_type(irq))
804 irq_set_irq_type(irq, irq_flags);
805
806 return irq;
807 }
808
809 }
810 return -ENOENT;
811 }
812 EXPORT_SYMBOL_GPL(acpi_dev_gpio_irq_get);
813
814 static acpi_status
815 acpi_gpio_adr_space_handler(u32 function, acpi_physical_address address,
816 u32 bits, u64 *value, void *handler_context,
817 void *region_context)
818 {
819 struct acpi_gpio_chip *achip = region_context;
820 struct gpio_chip *chip = achip->chip;
821 struct acpi_resource_gpio *agpio;
822 struct acpi_resource *ares;
823 int pin_index = (int)address;
824 acpi_status status;
825 int length;
826 int i;
827
828 status = acpi_buffer_to_resource(achip->conn_info.connection,
829 achip->conn_info.length, &ares);
830 if (ACPI_FAILURE(status))
831 return status;
832
833 if (WARN_ON(ares->type != ACPI_RESOURCE_TYPE_GPIO)) {
834 ACPI_FREE(ares);
835 return AE_BAD_PARAMETER;
836 }
837
838 agpio = &ares->data.gpio;
839
840 if (WARN_ON(agpio->io_restriction == ACPI_IO_RESTRICT_INPUT &&
841 function == ACPI_WRITE)) {
842 ACPI_FREE(ares);
843 return AE_BAD_PARAMETER;
844 }
845
846 length = min(agpio->pin_table_length, (u16)(pin_index + bits));
847 for (i = pin_index; i < length; ++i) {
848 int pin = agpio->pin_table[i];
849 struct acpi_gpio_connection *conn;
850 struct gpio_desc *desc;
851 bool found;
852
853 mutex_lock(&achip->conn_lock);
854
855 found = false;
856 list_for_each_entry(conn, &achip->conns, node) {
857 if (conn->pin == pin) {
858 found = true;
859 desc = conn->desc;
860 break;
861 }
862 }
863
864 /*
865 * The same GPIO can be shared between operation region and
866 * event but only if the access here is ACPI_READ. In that
867 * case we "borrow" the event GPIO instead.
868 */
869 if (!found && agpio->sharable == ACPI_SHARED &&
870 function == ACPI_READ) {
871 struct acpi_gpio_event *event;
872
873 list_for_each_entry(event, &achip->events, node) {
874 if (event->pin == pin) {
875 desc = event->desc;
876 found = true;
877 break;
878 }
879 }
880 }
881
882 if (!found) {
883 enum gpiod_flags flags = acpi_gpio_to_gpiod_flags(agpio);
884 const char *label = "ACPI:OpRegion";
885 int err;
886
887 desc = gpiochip_request_own_desc(chip, pin, label);
888 if (IS_ERR(desc)) {
889 status = AE_ERROR;
890 mutex_unlock(&achip->conn_lock);
891 goto out;
892 }
893
894 err = gpiod_configure_flags(desc, label, 0, flags);
895 if (err < 0) {
896 status = AE_NOT_CONFIGURED;
897 gpiochip_free_own_desc(desc);
898 mutex_unlock(&achip->conn_lock);
899 goto out;
900 }
901
902 conn = kzalloc(sizeof(*conn), GFP_KERNEL);
903 if (!conn) {
904 status = AE_NO_MEMORY;
905 gpiochip_free_own_desc(desc);
906 mutex_unlock(&achip->conn_lock);
907 goto out;
908 }
909
910 conn->pin = pin;
911 conn->desc = desc;
912 list_add_tail(&conn->node, &achip->conns);
913 }
914
915 mutex_unlock(&achip->conn_lock);
916
917 if (function == ACPI_WRITE)
918 gpiod_set_raw_value_cansleep(desc,
919 !!((1 << i) & *value));
920 else
921 *value |= (u64)gpiod_get_raw_value_cansleep(desc) << i;
922 }
923
924 out:
925 ACPI_FREE(ares);
926 return status;
927 }
928
929 static void acpi_gpiochip_request_regions(struct acpi_gpio_chip *achip)
930 {
931 struct gpio_chip *chip = achip->chip;
932 acpi_handle handle = ACPI_HANDLE(chip->parent);
933 acpi_status status;
934
935 INIT_LIST_HEAD(&achip->conns);
936 mutex_init(&achip->conn_lock);
937 status = acpi_install_address_space_handler(handle, ACPI_ADR_SPACE_GPIO,
938 acpi_gpio_adr_space_handler,
939 NULL, achip);
940 if (ACPI_FAILURE(status))
941 dev_err(chip->parent,
942 "Failed to install GPIO OpRegion handler\n");
943 }
944
945 static void acpi_gpiochip_free_regions(struct acpi_gpio_chip *achip)
946 {
947 struct gpio_chip *chip = achip->chip;
948 acpi_handle handle = ACPI_HANDLE(chip->parent);
949 struct acpi_gpio_connection *conn, *tmp;
950 acpi_status status;
951
952 status = acpi_remove_address_space_handler(handle, ACPI_ADR_SPACE_GPIO,
953 acpi_gpio_adr_space_handler);
954 if (ACPI_FAILURE(status)) {
955 dev_err(chip->parent,
956 "Failed to remove GPIO OpRegion handler\n");
957 return;
958 }
959
960 list_for_each_entry_safe_reverse(conn, tmp, &achip->conns, node) {
961 gpiochip_free_own_desc(conn->desc);
962 list_del(&conn->node);
963 kfree(conn);
964 }
965 }
966
967 static struct gpio_desc *acpi_gpiochip_parse_own_gpio(
968 struct acpi_gpio_chip *achip, struct fwnode_handle *fwnode,
969 const char **name, unsigned int *lflags, unsigned int *dflags)
970 {
971 struct gpio_chip *chip = achip->chip;
972 struct gpio_desc *desc;
973 u32 gpios[2];
974 int ret;
975
976 *lflags = 0;
977 *dflags = 0;
978 *name = NULL;
979
980 ret = fwnode_property_read_u32_array(fwnode, "gpios", gpios,
981 ARRAY_SIZE(gpios));
982 if (ret < 0)
983 return ERR_PTR(ret);
984
985 desc = gpiochip_get_desc(chip, gpios[0]);
986 if (IS_ERR(desc))
987 return desc;
988
989 if (gpios[1])
990 *lflags |= GPIO_ACTIVE_LOW;
991
992 if (fwnode_property_present(fwnode, "input"))
993 *dflags |= GPIOD_IN;
994 else if (fwnode_property_present(fwnode, "output-low"))
995 *dflags |= GPIOD_OUT_LOW;
996 else if (fwnode_property_present(fwnode, "output-high"))
997 *dflags |= GPIOD_OUT_HIGH;
998 else
999 return ERR_PTR(-EINVAL);
1000
1001 fwnode_property_read_string(fwnode, "line-name", name);
1002
1003 return desc;
1004 }
1005
1006 static void acpi_gpiochip_scan_gpios(struct acpi_gpio_chip *achip)
1007 {
1008 struct gpio_chip *chip = achip->chip;
1009 struct fwnode_handle *fwnode;
1010
1011 device_for_each_child_node(chip->parent, fwnode) {
1012 unsigned int lflags, dflags;
1013 struct gpio_desc *desc;
1014 const char *name;
1015 int ret;
1016
1017 if (!fwnode_property_present(fwnode, "gpio-hog"))
1018 continue;
1019
1020 desc = acpi_gpiochip_parse_own_gpio(achip, fwnode, &name,
1021 &lflags, &dflags);
1022 if (IS_ERR(desc))
1023 continue;
1024
1025 ret = gpiod_hog(desc, name, lflags, dflags);
1026 if (ret) {
1027 dev_err(chip->parent, "Failed to hog GPIO\n");
1028 fwnode_handle_put(fwnode);
1029 return;
1030 }
1031 }
1032 }
1033
1034 void acpi_gpiochip_add(struct gpio_chip *chip)
1035 {
1036 struct acpi_gpio_chip *acpi_gpio;
1037 acpi_handle handle;
1038 acpi_status status;
1039
1040 if (!chip || !chip->parent)
1041 return;
1042
1043 handle = ACPI_HANDLE(chip->parent);
1044 if (!handle)
1045 return;
1046
1047 acpi_gpio = kzalloc(sizeof(*acpi_gpio), GFP_KERNEL);
1048 if (!acpi_gpio) {
1049 dev_err(chip->parent,
1050 "Failed to allocate memory for ACPI GPIO chip\n");
1051 return;
1052 }
1053
1054 acpi_gpio->chip = chip;
1055 INIT_LIST_HEAD(&acpi_gpio->events);
1056 INIT_LIST_HEAD(&acpi_gpio->deferred_req_irqs_list_entry);
1057
1058 status = acpi_attach_data(handle, acpi_gpio_chip_dh, acpi_gpio);
1059 if (ACPI_FAILURE(status)) {
1060 dev_err(chip->parent, "Failed to attach ACPI GPIO chip\n");
1061 kfree(acpi_gpio);
1062 return;
1063 }
1064
1065 if (!chip->names)
1066 devprop_gpiochip_set_names(chip, dev_fwnode(chip->parent));
1067
1068 acpi_gpiochip_request_regions(acpi_gpio);
1069 acpi_gpiochip_scan_gpios(acpi_gpio);
1070 acpi_walk_dep_device_list(handle);
1071 }
1072
1073 void acpi_gpiochip_remove(struct gpio_chip *chip)
1074 {
1075 struct acpi_gpio_chip *acpi_gpio;
1076 acpi_handle handle;
1077 acpi_status status;
1078
1079 if (!chip || !chip->parent)
1080 return;
1081
1082 handle = ACPI_HANDLE(chip->parent);
1083 if (!handle)
1084 return;
1085
1086 status = acpi_get_data(handle, acpi_gpio_chip_dh, (void **)&acpi_gpio);
1087 if (ACPI_FAILURE(status)) {
1088 dev_warn(chip->parent, "Failed to retrieve ACPI GPIO chip\n");
1089 return;
1090 }
1091
1092 acpi_gpiochip_free_regions(acpi_gpio);
1093
1094 acpi_detach_data(handle, acpi_gpio_chip_dh);
1095 kfree(acpi_gpio);
1096 }
1097
1098 static int acpi_gpio_package_count(const union acpi_object *obj)
1099 {
1100 const union acpi_object *element = obj->package.elements;
1101 const union acpi_object *end = element + obj->package.count;
1102 unsigned int count = 0;
1103
1104 while (element < end) {
1105 switch (element->type) {
1106 case ACPI_TYPE_LOCAL_REFERENCE:
1107 element += 3;
1108 /* Fallthrough */
1109 case ACPI_TYPE_INTEGER:
1110 element++;
1111 count++;
1112 break;
1113
1114 default:
1115 return -EPROTO;
1116 }
1117 }
1118
1119 return count;
1120 }
1121
1122 static int acpi_find_gpio_count(struct acpi_resource *ares, void *data)
1123 {
1124 unsigned int *count = data;
1125
1126 if (ares->type == ACPI_RESOURCE_TYPE_GPIO)
1127 *count += ares->data.gpio.pin_table_length;
1128
1129 return 1;
1130 }
1131
1132 /**
1133 * acpi_gpio_count - return the number of GPIOs associated with a
1134 * device / function or -ENOENT if no GPIO has been
1135 * assigned to the requested function.
1136 * @dev: GPIO consumer, can be NULL for system-global GPIOs
1137 * @con_id: function within the GPIO consumer
1138 */
1139 int acpi_gpio_count(struct device *dev, const char *con_id)
1140 {
1141 struct acpi_device *adev = ACPI_COMPANION(dev);
1142 const union acpi_object *obj;
1143 const struct acpi_gpio_mapping *gm;
1144 int count = -ENOENT;
1145 int ret;
1146 char propname[32];
1147 unsigned int i;
1148
1149 /* Try first from _DSD */
1150 for (i = 0; i < ARRAY_SIZE(gpio_suffixes); i++) {
1151 if (con_id)
1152 snprintf(propname, sizeof(propname), "%s-%s",
1153 con_id, gpio_suffixes[i]);
1154 else
1155 snprintf(propname, sizeof(propname), "%s",
1156 gpio_suffixes[i]);
1157
1158 ret = acpi_dev_get_property(adev, propname, ACPI_TYPE_ANY,
1159 &obj);
1160 if (ret == 0) {
1161 if (obj->type == ACPI_TYPE_LOCAL_REFERENCE)
1162 count = 1;
1163 else if (obj->type == ACPI_TYPE_PACKAGE)
1164 count = acpi_gpio_package_count(obj);
1165 } else if (adev->driver_gpios) {
1166 for (gm = adev->driver_gpios; gm->name; gm++)
1167 if (strcmp(propname, gm->name) == 0) {
1168 count = gm->size;
1169 break;
1170 }
1171 }
1172 if (count > 0)
1173 break;
1174 }
1175
1176 /* Then from plain _CRS GPIOs */
1177 if (count < 0) {
1178 struct list_head resource_list;
1179 unsigned int crs_count = 0;
1180
1181 if (!acpi_can_fallback_to_crs(adev, con_id))
1182 return count;
1183
1184 INIT_LIST_HEAD(&resource_list);
1185 acpi_dev_get_resources(adev, &resource_list,
1186 acpi_find_gpio_count, &crs_count);
1187 acpi_dev_free_resource_list(&resource_list);
1188 if (crs_count > 0)
1189 count = crs_count;
1190 }
1191 return count ? count : -ENOENT;
1192 }
1193
1194 bool acpi_can_fallback_to_crs(struct acpi_device *adev, const char *con_id)
1195 {
1196 /* Never allow fallback if the device has properties */
1197 if (acpi_dev_has_props(adev) || adev->driver_gpios)
1198 return false;
1199
1200 return con_id == NULL;
1201 }
1202
1203 /* Run deferred acpi_gpiochip_request_interrupts() */
1204 static int acpi_gpio_handle_deferred_request_interrupts(void)
1205 {
1206 struct acpi_gpio_chip *acpi_gpio, *tmp;
1207
1208 mutex_lock(&acpi_gpio_deferred_req_irqs_lock);
1209 list_for_each_entry_safe(acpi_gpio, tmp,
1210 &acpi_gpio_deferred_req_irqs_list,
1211 deferred_req_irqs_list_entry) {
1212 acpi_handle handle;
1213
1214 handle = ACPI_HANDLE(acpi_gpio->chip->parent);
1215 acpi_walk_resources(handle, "_AEI",
1216 acpi_gpiochip_request_interrupt, acpi_gpio);
1217
1218 list_del_init(&acpi_gpio->deferred_req_irqs_list_entry);
1219 }
1220
1221 acpi_gpio_deferred_req_irqs_done = true;
1222 mutex_unlock(&acpi_gpio_deferred_req_irqs_lock);
1223
1224 return 0;
1225 }
1226 /* We must use _sync so that this runs after the first deferred_probe run */
1227 late_initcall_sync(acpi_gpio_handle_deferred_request_interrupts);
Linux with added FPC-III support