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mm/slab: sanity-check page type when looking up cache
[linux/fpc-iii.git] / drivers / gpio / gpiolib-acpi.c
blob39f2f9035c11df2b7c0d7446745a0c83cf7e0cc2
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 /**
23 * struct acpi_gpio_event - ACPI GPIO event handler data
24 *
25 * @node: list-entry of the events list of the struct acpi_gpio_chip
26 * @handle: handle of ACPI method to execute when the IRQ triggers
27 * @handler: handler function to pass to request_irq() when requesting the IRQ
28 * @pin: GPIO pin number on the struct gpio_chip
29 * @irq: Linux IRQ number for the event, for request_irq() / free_irq()
30 * @irqflags: flags to pass to request_irq() when requesting the IRQ
31 * @irq_is_wake: If the ACPI flags indicate the IRQ is a wakeup source
32 * @irq_requested:True if request_irq() has been done
33 * @desc: struct gpio_desc for the GPIO pin for this event
34 */
35 struct acpi_gpio_event {
36 struct list_head node;
37 acpi_handle handle;
38 irq_handler_t handler;
39 unsigned int pin;
40 unsigned int irq;
41 unsigned long irqflags;
42 bool irq_is_wake;
43 bool irq_requested;
44 struct gpio_desc *desc;
45 };
46
47 struct acpi_gpio_connection {
48 struct list_head node;
49 unsigned int pin;
50 struct gpio_desc *desc;
51 };
52
53 struct acpi_gpio_chip {
54 /*
55 * ACPICA requires that the first field of the context parameter
56 * passed to acpi_install_address_space_handler() is large enough
57 * to hold struct acpi_connection_info.
58 */
59 struct acpi_connection_info conn_info;
60 struct list_head conns;
61 struct mutex conn_lock;
62 struct gpio_chip *chip;
63 struct list_head events;
64 struct list_head deferred_req_irqs_list_entry;
65 };
66
67 /*
68 * For GPIO chips which call acpi_gpiochip_request_interrupts() before late_init
69 * (so builtin drivers) we register the ACPI GpioInt IRQ handlers from a
70 * late_initcall_sync() handler, so that other builtin drivers can register their
71 * OpRegions before the event handlers can run. This list contains GPIO chips
72 * for which the acpi_gpiochip_request_irqs() call has been deferred.
73 */
74 static DEFINE_MUTEX(acpi_gpio_deferred_req_irqs_lock);
75 static LIST_HEAD(acpi_gpio_deferred_req_irqs_list);
76 static bool acpi_gpio_deferred_req_irqs_done;
77
78 static int acpi_gpiochip_find(struct gpio_chip *gc, void *data)
79 {
80 if (!gc->parent)
81 return false;
82
83 return ACPI_HANDLE(gc->parent) == data;
84 }
85
86 /**
87 * acpi_get_gpiod() - Translate ACPI GPIO pin to GPIO descriptor usable with GPIO API
88 * @path: ACPI GPIO controller full path name, (e.g. "\\_SB.GPO1")
89 * @pin: ACPI GPIO pin number (0-based, controller-relative)
90 *
91 * Return: GPIO descriptor to use with Linux generic GPIO API, or ERR_PTR
92 * error value. Specifically returns %-EPROBE_DEFER if the referenced GPIO
93 * controller does not have GPIO chip registered at the moment. This is to
94 * support probe deferral.
95 */
96 static struct gpio_desc *acpi_get_gpiod(char *path, int pin)
97 {
98 struct gpio_chip *chip;
99 acpi_handle handle;
100 acpi_status status;
101
102 status = acpi_get_handle(NULL, path, &handle);
103 if (ACPI_FAILURE(status))
104 return ERR_PTR(-ENODEV);
105
106 chip = gpiochip_find(handle, acpi_gpiochip_find);
107 if (!chip)
108 return ERR_PTR(-EPROBE_DEFER);
109
110 return gpiochip_get_desc(chip, pin);
111 }
112
113 static irqreturn_t acpi_gpio_irq_handler(int irq, void *data)
114 {
115 struct acpi_gpio_event *event = data;
116
117 acpi_evaluate_object(event->handle, NULL, NULL, NULL);
118
119 return IRQ_HANDLED;
120 }
121
122 static irqreturn_t acpi_gpio_irq_handler_evt(int irq, void *data)
123 {
124 struct acpi_gpio_event *event = data;
125
126 acpi_execute_simple_method(event->handle, NULL, event->pin);
127
128 return IRQ_HANDLED;
129 }
130
131 static void acpi_gpio_chip_dh(acpi_handle handle, void *data)
132 {
133 /* The address of this function is used as a key. */
134 }
135
136 bool acpi_gpio_get_irq_resource(struct acpi_resource *ares,
137 struct acpi_resource_gpio **agpio)
138 {
139 struct acpi_resource_gpio *gpio;
140
141 if (ares->type != ACPI_RESOURCE_TYPE_GPIO)
142 return false;
143
144 gpio = &ares->data.gpio;
145 if (gpio->connection_type != ACPI_RESOURCE_GPIO_TYPE_INT)
146 return false;
147
148 *agpio = gpio;
149 return true;
150 }
151 EXPORT_SYMBOL_GPL(acpi_gpio_get_irq_resource);
152
153 static void acpi_gpiochip_request_irq(struct acpi_gpio_chip *acpi_gpio,
154 struct acpi_gpio_event *event)
155 {
156 int ret, value;
157
158 ret = request_threaded_irq(event->irq, NULL, event->handler,
159 event->irqflags, "ACPI:Event", event);
160 if (ret) {
161 dev_err(acpi_gpio->chip->parent,
162 "Failed to setup interrupt handler for %d\n",
163 event->irq);
164 return;
165 }
166
167 if (event->irq_is_wake)
168 enable_irq_wake(event->irq);
169
170 event->irq_requested = true;
171
172 /* Make sure we trigger the initial state of edge-triggered IRQs */
173 value = gpiod_get_raw_value_cansleep(event->desc);
174 if (((event->irqflags & IRQF_TRIGGER_RISING) && value == 1) ||
175 ((event->irqflags & IRQF_TRIGGER_FALLING) && value == 0))
176 event->handler(event->irq, event);
177 }
178
179 static void acpi_gpiochip_request_irqs(struct acpi_gpio_chip *acpi_gpio)
180 {
181 struct acpi_gpio_event *event;
182
183 list_for_each_entry(event, &acpi_gpio->events, node)
184 acpi_gpiochip_request_irq(acpi_gpio, event);
185 }
186
187 static acpi_status acpi_gpiochip_alloc_event(struct acpi_resource *ares,
188 void *context)
189 {
190 struct acpi_gpio_chip *acpi_gpio = context;
191 struct gpio_chip *chip = acpi_gpio->chip;
192 struct acpi_resource_gpio *agpio;
193 acpi_handle handle, evt_handle;
194 struct acpi_gpio_event *event;
195 irq_handler_t handler = NULL;
196 struct gpio_desc *desc;
197 int ret, pin, irq;
198
199 if (!acpi_gpio_get_irq_resource(ares, &agpio))
200 return AE_OK;
201
202 handle = ACPI_HANDLE(chip->parent);
203 pin = agpio->pin_table[0];
204
205 if (pin <= 255) {
206 char ev_name[5];
207 sprintf(ev_name, "_%c%02hhX",
208 agpio->triggering == ACPI_EDGE_SENSITIVE ? 'E' : 'L',
209 pin);
210 if (ACPI_SUCCESS(acpi_get_handle(handle, ev_name, &evt_handle)))
211 handler = acpi_gpio_irq_handler;
212 }
213 if (!handler) {
214 if (ACPI_SUCCESS(acpi_get_handle(handle, "_EVT", &evt_handle)))
215 handler = acpi_gpio_irq_handler_evt;
216 }
217 if (!handler)
218 return AE_OK;
219
220 desc = gpiochip_request_own_desc(chip, pin, "ACPI:Event",
221 GPIO_ACTIVE_HIGH, GPIOD_IN);
222 if (IS_ERR(desc)) {
223 dev_err(chip->parent, "Failed to request GPIO\n");
224 return AE_ERROR;
225 }
226
227 ret = gpiochip_lock_as_irq(chip, pin);
228 if (ret) {
229 dev_err(chip->parent, "Failed to lock GPIO as interrupt\n");
230 goto fail_free_desc;
231 }
232
233 irq = gpiod_to_irq(desc);
234 if (irq < 0) {
235 dev_err(chip->parent, "Failed to translate GPIO to IRQ\n");
236 goto fail_unlock_irq;
237 }
238
239 event = kzalloc(sizeof(*event), GFP_KERNEL);
240 if (!event)
241 goto fail_unlock_irq;
242
243 event->irqflags = IRQF_ONESHOT;
244 if (agpio->triggering == ACPI_LEVEL_SENSITIVE) {
245 if (agpio->polarity == ACPI_ACTIVE_HIGH)
246 event->irqflags |= IRQF_TRIGGER_HIGH;
247 else
248 event->irqflags |= IRQF_TRIGGER_LOW;
249 } else {
250 switch (agpio->polarity) {
251 case ACPI_ACTIVE_HIGH:
252 event->irqflags |= IRQF_TRIGGER_RISING;
253 break;
254 case ACPI_ACTIVE_LOW:
255 event->irqflags |= IRQF_TRIGGER_FALLING;
256 break;
257 default:
258 event->irqflags |= IRQF_TRIGGER_RISING |
259 IRQF_TRIGGER_FALLING;
260 break;
261 }
262 }
263
264 event->handle = evt_handle;
265 event->handler = handler;
266 event->irq = irq;
267 event->irq_is_wake = agpio->wake_capable == ACPI_WAKE_CAPABLE;
268 event->pin = pin;
269 event->desc = desc;
270
271 list_add_tail(&event->node, &acpi_gpio->events);
272
273 return AE_OK;
274
275 fail_unlock_irq:
276 gpiochip_unlock_as_irq(chip, pin);
277 fail_free_desc:
278 gpiochip_free_own_desc(desc);
279
280 return AE_ERROR;
281 }
282
283 /**
284 * acpi_gpiochip_request_interrupts() - Register isr for gpio chip ACPI events
285 * @chip: GPIO chip
286 *
287 * ACPI5 platforms can use GPIO signaled ACPI events. These GPIO interrupts are
288 * handled by ACPI event methods which need to be called from the GPIO
289 * chip's interrupt handler. acpi_gpiochip_request_interrupts() finds out which
290 * GPIO pins have ACPI event methods and assigns interrupt handlers that calls
291 * the ACPI event methods for those pins.
292 */
293 void acpi_gpiochip_request_interrupts(struct gpio_chip *chip)
294 {
295 struct acpi_gpio_chip *acpi_gpio;
296 acpi_handle handle;
297 acpi_status status;
298 bool defer;
299
300 if (!chip->parent || !chip->to_irq)
301 return;
302
303 handle = ACPI_HANDLE(chip->parent);
304 if (!handle)
305 return;
306
307 status = acpi_get_data(handle, acpi_gpio_chip_dh, (void **)&acpi_gpio);
308 if (ACPI_FAILURE(status))
309 return;
310
311 acpi_walk_resources(handle, "_AEI",
312 acpi_gpiochip_alloc_event, acpi_gpio);
313
314 mutex_lock(&acpi_gpio_deferred_req_irqs_lock);
315 defer = !acpi_gpio_deferred_req_irqs_done;
316 if (defer)
317 list_add(&acpi_gpio->deferred_req_irqs_list_entry,
318 &acpi_gpio_deferred_req_irqs_list);
319 mutex_unlock(&acpi_gpio_deferred_req_irqs_lock);
320
321 if (defer)
322 return;
323
324 acpi_gpiochip_request_irqs(acpi_gpio);
325 }
326 EXPORT_SYMBOL_GPL(acpi_gpiochip_request_interrupts);
327
328 /**
329 * acpi_gpiochip_free_interrupts() - Free GPIO ACPI event interrupts.
330 * @chip: GPIO chip
331 *
332 * Free interrupts associated with GPIO ACPI event method for the given
333 * GPIO chip.
334 */
335 void acpi_gpiochip_free_interrupts(struct gpio_chip *chip)
336 {
337 struct acpi_gpio_chip *acpi_gpio;
338 struct acpi_gpio_event *event, *ep;
339 acpi_handle handle;
340 acpi_status status;
341
342 if (!chip->parent || !chip->to_irq)
343 return;
344
345 handle = ACPI_HANDLE(chip->parent);
346 if (!handle)
347 return;
348
349 status = acpi_get_data(handle, acpi_gpio_chip_dh, (void **)&acpi_gpio);
350 if (ACPI_FAILURE(status))
351 return;
352
353 mutex_lock(&acpi_gpio_deferred_req_irqs_lock);
354 if (!list_empty(&acpi_gpio->deferred_req_irqs_list_entry))
355 list_del_init(&acpi_gpio->deferred_req_irqs_list_entry);
356 mutex_unlock(&acpi_gpio_deferred_req_irqs_lock);
357
358 list_for_each_entry_safe_reverse(event, ep, &acpi_gpio->events, node) {
359 if (event->irq_requested) {
360 if (event->irq_is_wake)
361 disable_irq_wake(event->irq);
362
363 free_irq(event->irq, event);
364 }
365
366 gpiochip_unlock_as_irq(chip, event->pin);
367 gpiochip_free_own_desc(event->desc);
368 list_del(&event->node);
369 kfree(event);
370 }
371 }
372 EXPORT_SYMBOL_GPL(acpi_gpiochip_free_interrupts);
373
374 int acpi_dev_add_driver_gpios(struct acpi_device *adev,
375 const struct acpi_gpio_mapping *gpios)
376 {
377 if (adev && gpios) {
378 adev->driver_gpios = gpios;
379 return 0;
380 }
381 return -EINVAL;
382 }
383 EXPORT_SYMBOL_GPL(acpi_dev_add_driver_gpios);
384
385 static void devm_acpi_dev_release_driver_gpios(struct device *dev, void *res)
386 {
387 acpi_dev_remove_driver_gpios(ACPI_COMPANION(dev));
388 }
389
390 int devm_acpi_dev_add_driver_gpios(struct device *dev,
391 const struct acpi_gpio_mapping *gpios)
392 {
393 void *res;
394 int ret;
395
396 res = devres_alloc(devm_acpi_dev_release_driver_gpios, 0, GFP_KERNEL);
397 if (!res)
398 return -ENOMEM;
399
400 ret = acpi_dev_add_driver_gpios(ACPI_COMPANION(dev), gpios);
401 if (ret) {
402 devres_free(res);
403 return ret;
404 }
405 devres_add(dev, res);
406 return 0;
407 }
408 EXPORT_SYMBOL_GPL(devm_acpi_dev_add_driver_gpios);
409
410 void devm_acpi_dev_remove_driver_gpios(struct device *dev)
411 {
412 WARN_ON(devres_release(dev, devm_acpi_dev_release_driver_gpios, NULL, NULL));
413 }
414 EXPORT_SYMBOL_GPL(devm_acpi_dev_remove_driver_gpios);
415
416 static bool acpi_get_driver_gpio_data(struct acpi_device *adev,
417 const char *name, int index,
418 struct fwnode_reference_args *args,
419 unsigned int *quirks)
420 {
421 const struct acpi_gpio_mapping *gm;
422
423 if (!adev->driver_gpios)
424 return false;
425
426 for (gm = adev->driver_gpios; gm->name; gm++)
427 if (!strcmp(name, gm->name) && gm->data && index < gm->size) {
428 const struct acpi_gpio_params *par = gm->data + index;
429
430 args->fwnode = acpi_fwnode_handle(adev);
431 args->args[0] = par->crs_entry_index;
432 args->args[1] = par->line_index;
433 args->args[2] = par->active_low;
434 args->nargs = 3;
435
436 *quirks = gm->quirks;
437 return true;
438 }
439
440 return false;
441 }
442
443 static enum gpiod_flags
444 acpi_gpio_to_gpiod_flags(const struct acpi_resource_gpio *agpio)
445 {
446 switch (agpio->io_restriction) {
447 case ACPI_IO_RESTRICT_INPUT:
448 return GPIOD_IN;
449 case ACPI_IO_RESTRICT_OUTPUT:
450 /*
451 * ACPI GPIO resources don't contain an initial value for the
452 * GPIO. Therefore we deduce that value from the pull field
453 * instead. If the pin is pulled up we assume default to be
454 * high, if it is pulled down we assume default to be low,
455 * otherwise we leave pin untouched.
456 */
457 switch (agpio->pin_config) {
458 case ACPI_PIN_CONFIG_PULLUP:
459 return GPIOD_OUT_HIGH;
460 case ACPI_PIN_CONFIG_PULLDOWN:
461 return GPIOD_OUT_LOW;
462 default:
463 break;
464 }
465 default:
466 break;
467 }
468
469 /*
470 * Assume that the BIOS has configured the direction and pull
471 * accordingly.
472 */
473 return GPIOD_ASIS;
474 }
475
476 static int
477 __acpi_gpio_update_gpiod_flags(enum gpiod_flags *flags, enum gpiod_flags update)
478 {
479 const enum gpiod_flags mask =
480 GPIOD_FLAGS_BIT_DIR_SET | GPIOD_FLAGS_BIT_DIR_OUT |
481 GPIOD_FLAGS_BIT_DIR_VAL;
482 int ret = 0;
483
484 /*
485 * Check if the BIOS has IoRestriction with explicitly set direction
486 * and update @flags accordingly. Otherwise use whatever caller asked
487 * for.
488 */
489 if (update & GPIOD_FLAGS_BIT_DIR_SET) {
490 enum gpiod_flags diff = *flags ^ update;
491
492 /*
493 * Check if caller supplied incompatible GPIO initialization
494 * flags.
495 *
496 * Return %-EINVAL to notify that firmware has different
497 * settings and we are going to use them.
498 */
499 if (((*flags & GPIOD_FLAGS_BIT_DIR_SET) && (diff & GPIOD_FLAGS_BIT_DIR_OUT)) ||
500 ((*flags & GPIOD_FLAGS_BIT_DIR_OUT) && (diff & GPIOD_FLAGS_BIT_DIR_VAL)))
501 ret = -EINVAL;
502 *flags = (*flags & ~mask) | (update & mask);
503 }
504 return ret;
505 }
506
507 int
508 acpi_gpio_update_gpiod_flags(enum gpiod_flags *flags, struct acpi_gpio_info *info)
509 {
510 struct device *dev = &info->adev->dev;
511 enum gpiod_flags old = *flags;
512 int ret;
513
514 ret = __acpi_gpio_update_gpiod_flags(&old, info->flags);
515 if (info->quirks & ACPI_GPIO_QUIRK_NO_IO_RESTRICTION) {
516 if (ret)
517 dev_warn(dev, FW_BUG "GPIO not in correct mode, fixing\n");
518 } else {
519 if (ret)
520 dev_dbg(dev, "Override GPIO initialization flags\n");
521 *flags = old;
522 }
523
524 return ret;
525 }
526
527 int acpi_gpio_update_gpiod_lookup_flags(unsigned long *lookupflags,
528 struct acpi_gpio_info *info)
529 {
530 switch (info->pin_config) {
531 case ACPI_PIN_CONFIG_PULLUP:
532 *lookupflags |= GPIO_PULL_UP;
533 break;
534 case ACPI_PIN_CONFIG_PULLDOWN:
535 *lookupflags |= GPIO_PULL_DOWN;
536 break;
537 default:
538 break;
539 }
540
541 if (info->polarity == GPIO_ACTIVE_LOW)
542 *lookupflags |= GPIO_ACTIVE_LOW;
543
544 return 0;
545 }
546
547 struct acpi_gpio_lookup {
548 struct acpi_gpio_info info;
549 int index;
550 int pin_index;
551 bool active_low;
552 struct gpio_desc *desc;
553 int n;
554 };
555
556 static int acpi_populate_gpio_lookup(struct acpi_resource *ares, void *data)
557 {
558 struct acpi_gpio_lookup *lookup = data;
559
560 if (ares->type != ACPI_RESOURCE_TYPE_GPIO)
561 return 1;
562
563 if (!lookup->desc) {
564 const struct acpi_resource_gpio *agpio = &ares->data.gpio;
565 bool gpioint = agpio->connection_type == ACPI_RESOURCE_GPIO_TYPE_INT;
566 int pin_index;
567
568 if (lookup->info.quirks & ACPI_GPIO_QUIRK_ONLY_GPIOIO && gpioint)
569 lookup->index++;
570
571 if (lookup->n++ != lookup->index)
572 return 1;
573
574 pin_index = lookup->pin_index;
575 if (pin_index >= agpio->pin_table_length)
576 return 1;
577
578 lookup->desc = acpi_get_gpiod(agpio->resource_source.string_ptr,
579 agpio->pin_table[pin_index]);
580 lookup->info.pin_config = agpio->pin_config;
581 lookup->info.gpioint = gpioint;
582
583 /*
584 * Polarity and triggering are only specified for GpioInt
585 * resource.
586 * Note: we expect here:
587 * - ACPI_ACTIVE_LOW == GPIO_ACTIVE_LOW
588 * - ACPI_ACTIVE_HIGH == GPIO_ACTIVE_HIGH
589 */
590 if (lookup->info.gpioint) {
591 lookup->info.flags = GPIOD_IN;
592 lookup->info.polarity = agpio->polarity;
593 lookup->info.triggering = agpio->triggering;
594 } else {
595 lookup->info.flags = acpi_gpio_to_gpiod_flags(agpio);
596 lookup->info.polarity = lookup->active_low;
597 }
598 }
599
600 return 1;
601 }
602
603 static int acpi_gpio_resource_lookup(struct acpi_gpio_lookup *lookup,
604 struct acpi_gpio_info *info)
605 {
606 struct acpi_device *adev = lookup->info.adev;
607 struct list_head res_list;
608 int ret;
609
610 INIT_LIST_HEAD(&res_list);
611
612 ret = acpi_dev_get_resources(adev, &res_list,
613 acpi_populate_gpio_lookup,
614 lookup);
615 if (ret < 0)
616 return ret;
617
618 acpi_dev_free_resource_list(&res_list);
619
620 if (!lookup->desc)
621 return -ENOENT;
622
623 if (info)
624 *info = lookup->info;
625 return 0;
626 }
627
628 static int acpi_gpio_property_lookup(struct fwnode_handle *fwnode,
629 const char *propname, int index,
630 struct acpi_gpio_lookup *lookup)
631 {
632 struct fwnode_reference_args args;
633 unsigned int quirks = 0;
634 int ret;
635
636 memset(&args, 0, sizeof(args));
637 ret = __acpi_node_get_property_reference(fwnode, propname, index, 3,
638 &args);
639 if (ret) {
640 struct acpi_device *adev = to_acpi_device_node(fwnode);
641
642 if (!adev)
643 return ret;
644
645 if (!acpi_get_driver_gpio_data(adev, propname, index, &args,
646 &quirks))
647 return ret;
648 }
649 /*
650 * The property was found and resolved, so need to lookup the GPIO based
651 * on returned args.
652 */
653 if (!to_acpi_device_node(args.fwnode))
654 return -EINVAL;
655 if (args.nargs != 3)
656 return -EPROTO;
657
658 lookup->index = args.args[0];
659 lookup->pin_index = args.args[1];
660 lookup->active_low = !!args.args[2];
661
662 lookup->info.adev = to_acpi_device_node(args.fwnode);
663 lookup->info.quirks = quirks;
664
665 return 0;
666 }
667
668 /**
669 * acpi_get_gpiod_by_index() - get a GPIO descriptor from device resources
670 * @adev: pointer to a ACPI device to get GPIO from
671 * @propname: Property name of the GPIO (optional)
672 * @index: index of GpioIo/GpioInt resource (starting from %0)
673 * @info: info pointer to fill in (optional)
674 *
675 * Function goes through ACPI resources for @adev and based on @index looks
676 * up a GpioIo/GpioInt resource, translates it to the Linux GPIO descriptor,
677 * and returns it. @index matches GpioIo/GpioInt resources only so if there
678 * are total %3 GPIO resources, the index goes from %0 to %2.
679 *
680 * If @propname is specified the GPIO is looked using device property. In
681 * that case @index is used to select the GPIO entry in the property value
682 * (in case of multiple).
683 *
684 * If the GPIO cannot be translated or there is an error, an ERR_PTR is
685 * returned.
686 *
687 * Note: if the GPIO resource has multiple entries in the pin list, this
688 * function only returns the first.
689 */
690 static struct gpio_desc *acpi_get_gpiod_by_index(struct acpi_device *adev,
691 const char *propname, int index,
692 struct acpi_gpio_info *info)
693 {
694 struct acpi_gpio_lookup lookup;
695 int ret;
696
697 if (!adev)
698 return ERR_PTR(-ENODEV);
699
700 memset(&lookup, 0, sizeof(lookup));
701 lookup.index = index;
702
703 if (propname) {
704 dev_dbg(&adev->dev, "GPIO: looking up %s\n", propname);
705
706 ret = acpi_gpio_property_lookup(acpi_fwnode_handle(adev),
707 propname, index, &lookup);
708 if (ret)
709 return ERR_PTR(ret);
710
711 dev_dbg(&adev->dev, "GPIO: _DSD returned %s %d %d %u\n",
712 dev_name(&lookup.info.adev->dev), lookup.index,
713 lookup.pin_index, lookup.active_low);
714 } else {
715 dev_dbg(&adev->dev, "GPIO: looking up %d in _CRS\n", index);
716 lookup.info.adev = adev;
717 }
718
719 ret = acpi_gpio_resource_lookup(&lookup, info);
720 return ret ? ERR_PTR(ret) : lookup.desc;
721 }
722
723 struct gpio_desc *acpi_find_gpio(struct device *dev,
724 const char *con_id,
725 unsigned int idx,
726 enum gpiod_flags *dflags,
727 unsigned long *lookupflags)
728 {
729 struct acpi_device *adev = ACPI_COMPANION(dev);
730 struct acpi_gpio_info info;
731 struct gpio_desc *desc;
732 char propname[32];
733 int i;
734
735 /* Try first from _DSD */
736 for (i = 0; i < ARRAY_SIZE(gpio_suffixes); i++) {
737 if (con_id) {
738 snprintf(propname, sizeof(propname), "%s-%s",
739 con_id, gpio_suffixes[i]);
740 } else {
741 snprintf(propname, sizeof(propname), "%s",
742 gpio_suffixes[i]);
743 }
744
745 desc = acpi_get_gpiod_by_index(adev, propname, idx, &info);
746 if (!IS_ERR(desc))
747 break;
748 if (PTR_ERR(desc) == -EPROBE_DEFER)
749 return ERR_CAST(desc);
750 }
751
752 /* Then from plain _CRS GPIOs */
753 if (IS_ERR(desc)) {
754 if (!acpi_can_fallback_to_crs(adev, con_id))
755 return ERR_PTR(-ENOENT);
756
757 desc = acpi_get_gpiod_by_index(adev, NULL, idx, &info);
758 if (IS_ERR(desc))
759 return desc;
760 }
761
762 if (info.gpioint &&
763 (*dflags == GPIOD_OUT_LOW || *dflags == GPIOD_OUT_HIGH)) {
764 dev_dbg(dev, "refusing GpioInt() entry when doing GPIOD_OUT_* lookup\n");
765 return ERR_PTR(-ENOENT);
766 }
767
768 acpi_gpio_update_gpiod_flags(dflags, &info);
769 acpi_gpio_update_gpiod_lookup_flags(lookupflags, &info);
770 return desc;
771 }
772
773 /**
774 * acpi_node_get_gpiod() - get a GPIO descriptor from ACPI resources
775 * @fwnode: pointer to an ACPI firmware node to get the GPIO information from
776 * @propname: Property name of the GPIO
777 * @index: index of GpioIo/GpioInt resource (starting from %0)
778 * @info: info pointer to fill in (optional)
779 *
780 * If @fwnode is an ACPI device object, call acpi_get_gpiod_by_index() for it.
781 * Otherwise (i.e. it is a data-only non-device object), use the property-based
782 * GPIO lookup to get to the GPIO resource with the relevant information and use
783 * that to obtain the GPIO descriptor to return.
784 *
785 * If the GPIO cannot be translated or there is an error an ERR_PTR is
786 * returned.
787 */
788 struct gpio_desc *acpi_node_get_gpiod(struct fwnode_handle *fwnode,
789 const char *propname, int index,
790 struct acpi_gpio_info *info)
791 {
792 struct acpi_gpio_lookup lookup;
793 struct acpi_device *adev;
794 int ret;
795
796 adev = to_acpi_device_node(fwnode);
797 if (adev)
798 return acpi_get_gpiod_by_index(adev, propname, index, info);
799
800 if (!is_acpi_data_node(fwnode))
801 return ERR_PTR(-ENODEV);
802
803 if (!propname)
804 return ERR_PTR(-EINVAL);
805
806 memset(&lookup, 0, sizeof(lookup));
807 lookup.index = index;
808
809 ret = acpi_gpio_property_lookup(fwnode, propname, index, &lookup);
810 if (ret)
811 return ERR_PTR(ret);
812
813 ret = acpi_gpio_resource_lookup(&lookup, info);
814 return ret ? ERR_PTR(ret) : lookup.desc;
815 }
816
817 /**
818 * acpi_dev_gpio_irq_get() - Find GpioInt and translate it to Linux IRQ number
819 * @adev: pointer to a ACPI device to get IRQ from
820 * @index: index of GpioInt resource (starting from %0)
821 *
822 * If the device has one or more GpioInt resources, this function can be
823 * used to translate from the GPIO offset in the resource to the Linux IRQ
824 * number.
825 *
826 * The function is idempotent, though each time it runs it will configure GPIO
827 * pin direction according to the flags in GpioInt resource.
828 *
829 * Return: Linux IRQ number (> %0) on success, negative errno on failure.
830 */
831 int acpi_dev_gpio_irq_get(struct acpi_device *adev, int index)
832 {
833 int idx, i;
834 unsigned int irq_flags;
835 int ret;
836
837 for (i = 0, idx = 0; idx <= index; i++) {
838 struct acpi_gpio_info info;
839 struct gpio_desc *desc;
840
841 desc = acpi_get_gpiod_by_index(adev, NULL, i, &info);
842
843 /* Ignore -EPROBE_DEFER, it only matters if idx matches */
844 if (IS_ERR(desc) && PTR_ERR(desc) != -EPROBE_DEFER)
845 return PTR_ERR(desc);
846
847 if (info.gpioint && idx++ == index) {
848 unsigned long lflags = GPIO_LOOKUP_FLAGS_DEFAULT;
849 char label[32];
850 int irq;
851
852 if (IS_ERR(desc))
853 return PTR_ERR(desc);
854
855 irq = gpiod_to_irq(desc);
856 if (irq < 0)
857 return irq;
858
859 snprintf(label, sizeof(label), "GpioInt() %d", index);
860 ret = gpiod_configure_flags(desc, label, lflags, info.flags);
861 if (ret < 0)
862 return ret;
863
864 irq_flags = acpi_dev_get_irq_type(info.triggering,
865 info.polarity);
866
867 /* Set type if specified and different than the current one */
868 if (irq_flags != IRQ_TYPE_NONE &&
869 irq_flags != irq_get_trigger_type(irq))
870 irq_set_irq_type(irq, irq_flags);
871
872 return irq;
873 }
874
875 }
876 return -ENOENT;
877 }
878 EXPORT_SYMBOL_GPL(acpi_dev_gpio_irq_get);
879
880 static acpi_status
881 acpi_gpio_adr_space_handler(u32 function, acpi_physical_address address,
882 u32 bits, u64 *value, void *handler_context,
883 void *region_context)
884 {
885 struct acpi_gpio_chip *achip = region_context;
886 struct gpio_chip *chip = achip->chip;
887 struct acpi_resource_gpio *agpio;
888 struct acpi_resource *ares;
889 int pin_index = (int)address;
890 acpi_status status;
891 int length;
892 int i;
893
894 status = acpi_buffer_to_resource(achip->conn_info.connection,
895 achip->conn_info.length, &ares);
896 if (ACPI_FAILURE(status))
897 return status;
898
899 if (WARN_ON(ares->type != ACPI_RESOURCE_TYPE_GPIO)) {
900 ACPI_FREE(ares);
901 return AE_BAD_PARAMETER;
902 }
903
904 agpio = &ares->data.gpio;
905
906 if (WARN_ON(agpio->io_restriction == ACPI_IO_RESTRICT_INPUT &&
907 function == ACPI_WRITE)) {
908 ACPI_FREE(ares);
909 return AE_BAD_PARAMETER;
910 }
911
912 length = min(agpio->pin_table_length, (u16)(pin_index + bits));
913 for (i = pin_index; i < length; ++i) {
914 int pin = agpio->pin_table[i];
915 struct acpi_gpio_connection *conn;
916 struct gpio_desc *desc;
917 bool found;
918
919 mutex_lock(&achip->conn_lock);
920
921 found = false;
922 list_for_each_entry(conn, &achip->conns, node) {
923 if (conn->pin == pin) {
924 found = true;
925 desc = conn->desc;
926 break;
927 }
928 }
929
930 /*
931 * The same GPIO can be shared between operation region and
932 * event but only if the access here is ACPI_READ. In that
933 * case we "borrow" the event GPIO instead.
934 */
935 if (!found && agpio->shareable == ACPI_SHARED &&
936 function == ACPI_READ) {
937 struct acpi_gpio_event *event;
938
939 list_for_each_entry(event, &achip->events, node) {
940 if (event->pin == pin) {
941 desc = event->desc;
942 found = true;
943 break;
944 }
945 }
946 }
947
948 if (!found) {
949 enum gpiod_flags flags = acpi_gpio_to_gpiod_flags(agpio);
950 const char *label = "ACPI:OpRegion";
951
952 desc = gpiochip_request_own_desc(chip, pin, label,
953 GPIO_ACTIVE_HIGH,
954 flags);
955 if (IS_ERR(desc)) {
956 status = AE_ERROR;
957 mutex_unlock(&achip->conn_lock);
958 goto out;
959 }
960
961 conn = kzalloc(sizeof(*conn), GFP_KERNEL);
962 if (!conn) {
963 status = AE_NO_MEMORY;
964 gpiochip_free_own_desc(desc);
965 mutex_unlock(&achip->conn_lock);
966 goto out;
967 }
968
969 conn->pin = pin;
970 conn->desc = desc;
971 list_add_tail(&conn->node, &achip->conns);
972 }
973
974 mutex_unlock(&achip->conn_lock);
975
976 if (function == ACPI_WRITE)
977 gpiod_set_raw_value_cansleep(desc,
978 !!((1 << i) & *value));
979 else
980 *value |= (u64)gpiod_get_raw_value_cansleep(desc) << i;
981 }
982
983 out:
984 ACPI_FREE(ares);
985 return status;
986 }
987
988 static void acpi_gpiochip_request_regions(struct acpi_gpio_chip *achip)
989 {
990 struct gpio_chip *chip = achip->chip;
991 acpi_handle handle = ACPI_HANDLE(chip->parent);
992 acpi_status status;
993
994 INIT_LIST_HEAD(&achip->conns);
995 mutex_init(&achip->conn_lock);
996 status = acpi_install_address_space_handler(handle, ACPI_ADR_SPACE_GPIO,
997 acpi_gpio_adr_space_handler,
998 NULL, achip);
999 if (ACPI_FAILURE(status))
1000 dev_err(chip->parent,
1001 "Failed to install GPIO OpRegion handler\n");
1002 }
1003
1004 static void acpi_gpiochip_free_regions(struct acpi_gpio_chip *achip)
1005 {
1006 struct gpio_chip *chip = achip->chip;
1007 acpi_handle handle = ACPI_HANDLE(chip->parent);
1008 struct acpi_gpio_connection *conn, *tmp;
1009 acpi_status status;
1010
1011 status = acpi_remove_address_space_handler(handle, ACPI_ADR_SPACE_GPIO,
1012 acpi_gpio_adr_space_handler);
1013 if (ACPI_FAILURE(status)) {
1014 dev_err(chip->parent,
1015 "Failed to remove GPIO OpRegion handler\n");
1016 return;
1017 }
1018
1019 list_for_each_entry_safe_reverse(conn, tmp, &achip->conns, node) {
1020 gpiochip_free_own_desc(conn->desc);
1021 list_del(&conn->node);
1022 kfree(conn);
1023 }
1024 }
1025
1026 static struct gpio_desc *
1027 acpi_gpiochip_parse_own_gpio(struct acpi_gpio_chip *achip,
1028 struct fwnode_handle *fwnode,
1029 const char **name,
1030 unsigned long *lflags,
1031 enum gpiod_flags *dflags)
1032 {
1033 struct gpio_chip *chip = achip->chip;
1034 struct gpio_desc *desc;
1035 u32 gpios[2];
1036 int ret;
1037
1038 *lflags = GPIO_LOOKUP_FLAGS_DEFAULT;
1039 *dflags = 0;
1040 *name = NULL;
1041
1042 ret = fwnode_property_read_u32_array(fwnode, "gpios", gpios,
1043 ARRAY_SIZE(gpios));
1044 if (ret < 0)
1045 return ERR_PTR(ret);
1046
1047 desc = gpiochip_get_desc(chip, gpios[0]);
1048 if (IS_ERR(desc))
1049 return desc;
1050
1051 if (gpios[1])
1052 *lflags |= GPIO_ACTIVE_LOW;
1053
1054 if (fwnode_property_present(fwnode, "input"))
1055 *dflags |= GPIOD_IN;
1056 else if (fwnode_property_present(fwnode, "output-low"))
1057 *dflags |= GPIOD_OUT_LOW;
1058 else if (fwnode_property_present(fwnode, "output-high"))
1059 *dflags |= GPIOD_OUT_HIGH;
1060 else
1061 return ERR_PTR(-EINVAL);
1062
1063 fwnode_property_read_string(fwnode, "line-name", name);
1064
1065 return desc;
1066 }
1067
1068 static void acpi_gpiochip_scan_gpios(struct acpi_gpio_chip *achip)
1069 {
1070 struct gpio_chip *chip = achip->chip;
1071 struct fwnode_handle *fwnode;
1072
1073 device_for_each_child_node(chip->parent, fwnode) {
1074 unsigned long lflags;
1075 enum gpiod_flags dflags;
1076 struct gpio_desc *desc;
1077 const char *name;
1078 int ret;
1079
1080 if (!fwnode_property_present(fwnode, "gpio-hog"))
1081 continue;
1082
1083 desc = acpi_gpiochip_parse_own_gpio(achip, fwnode, &name,
1084 &lflags, &dflags);
1085 if (IS_ERR(desc))
1086 continue;
1087
1088 ret = gpiod_hog(desc, name, lflags, dflags);
1089 if (ret) {
1090 dev_err(chip->parent, "Failed to hog GPIO\n");
1091 fwnode_handle_put(fwnode);
1092 return;
1093 }
1094 }
1095 }
1096
1097 void acpi_gpiochip_add(struct gpio_chip *chip)
1098 {
1099 struct acpi_gpio_chip *acpi_gpio;
1100 acpi_handle handle;
1101 acpi_status status;
1102
1103 if (!chip || !chip->parent)
1104 return;
1105
1106 handle = ACPI_HANDLE(chip->parent);
1107 if (!handle)
1108 return;
1109
1110 acpi_gpio = kzalloc(sizeof(*acpi_gpio), GFP_KERNEL);
1111 if (!acpi_gpio) {
1112 dev_err(chip->parent,
1113 "Failed to allocate memory for ACPI GPIO chip\n");
1114 return;
1115 }
1116
1117 acpi_gpio->chip = chip;
1118 INIT_LIST_HEAD(&acpi_gpio->events);
1119 INIT_LIST_HEAD(&acpi_gpio->deferred_req_irqs_list_entry);
1120
1121 status = acpi_attach_data(handle, acpi_gpio_chip_dh, acpi_gpio);
1122 if (ACPI_FAILURE(status)) {
1123 dev_err(chip->parent, "Failed to attach ACPI GPIO chip\n");
1124 kfree(acpi_gpio);
1125 return;
1126 }
1127
1128 if (!chip->names)
1129 devprop_gpiochip_set_names(chip, dev_fwnode(chip->parent));
1130
1131 acpi_gpiochip_request_regions(acpi_gpio);
1132 acpi_gpiochip_scan_gpios(acpi_gpio);
1133 acpi_walk_dep_device_list(handle);
1134 }
1135
1136 void acpi_gpiochip_remove(struct gpio_chip *chip)
1137 {
1138 struct acpi_gpio_chip *acpi_gpio;
1139 acpi_handle handle;
1140 acpi_status status;
1141
1142 if (!chip || !chip->parent)
1143 return;
1144
1145 handle = ACPI_HANDLE(chip->parent);
1146 if (!handle)
1147 return;
1148
1149 status = acpi_get_data(handle, acpi_gpio_chip_dh, (void **)&acpi_gpio);
1150 if (ACPI_FAILURE(status)) {
1151 dev_warn(chip->parent, "Failed to retrieve ACPI GPIO chip\n");
1152 return;
1153 }
1154
1155 acpi_gpiochip_free_regions(acpi_gpio);
1156
1157 acpi_detach_data(handle, acpi_gpio_chip_dh);
1158 kfree(acpi_gpio);
1159 }
1160
1161 static int acpi_gpio_package_count(const union acpi_object *obj)
1162 {
1163 const union acpi_object *element = obj->package.elements;
1164 const union acpi_object *end = element + obj->package.count;
1165 unsigned int count = 0;
1166
1167 while (element < end) {
1168 switch (element->type) {
1169 case ACPI_TYPE_LOCAL_REFERENCE:
1170 element += 3;
1171 /* Fallthrough */
1172 case ACPI_TYPE_INTEGER:
1173 element++;
1174 count++;
1175 break;
1176
1177 default:
1178 return -EPROTO;
1179 }
1180 }
1181
1182 return count;
1183 }
1184
1185 static int acpi_find_gpio_count(struct acpi_resource *ares, void *data)
1186 {
1187 unsigned int *count = data;
1188
1189 if (ares->type == ACPI_RESOURCE_TYPE_GPIO)
1190 *count += ares->data.gpio.pin_table_length;
1191
1192 return 1;
1193 }
1194
1195 /**
1196 * acpi_gpio_count - count the GPIOs associated with a device / function
1197 * @dev: GPIO consumer, can be %NULL for system-global GPIOs
1198 * @con_id: function within the GPIO consumer
1199 *
1200 * Return:
1201 * The number of GPIOs associated with a device / function or %-ENOENT,
1202 * if no GPIO has been assigned to the requested function.
1203 */
1204 int acpi_gpio_count(struct device *dev, const char *con_id)
1205 {
1206 struct acpi_device *adev = ACPI_COMPANION(dev);
1207 const union acpi_object *obj;
1208 const struct acpi_gpio_mapping *gm;
1209 int count = -ENOENT;
1210 int ret;
1211 char propname[32];
1212 unsigned int i;
1213
1214 /* Try first from _DSD */
1215 for (i = 0; i < ARRAY_SIZE(gpio_suffixes); i++) {
1216 if (con_id)
1217 snprintf(propname, sizeof(propname), "%s-%s",
1218 con_id, gpio_suffixes[i]);
1219 else
1220 snprintf(propname, sizeof(propname), "%s",
1221 gpio_suffixes[i]);
1222
1223 ret = acpi_dev_get_property(adev, propname, ACPI_TYPE_ANY,
1224 &obj);
1225 if (ret == 0) {
1226 if (obj->type == ACPI_TYPE_LOCAL_REFERENCE)
1227 count = 1;
1228 else if (obj->type == ACPI_TYPE_PACKAGE)
1229 count = acpi_gpio_package_count(obj);
1230 } else if (adev->driver_gpios) {
1231 for (gm = adev->driver_gpios; gm->name; gm++)
1232 if (strcmp(propname, gm->name) == 0) {
1233 count = gm->size;
1234 break;
1235 }
1236 }
1237 if (count > 0)
1238 break;
1239 }
1240
1241 /* Then from plain _CRS GPIOs */
1242 if (count < 0) {
1243 struct list_head resource_list;
1244 unsigned int crs_count = 0;
1245
1246 if (!acpi_can_fallback_to_crs(adev, con_id))
1247 return count;
1248
1249 INIT_LIST_HEAD(&resource_list);
1250 acpi_dev_get_resources(adev, &resource_list,
1251 acpi_find_gpio_count, &crs_count);
1252 acpi_dev_free_resource_list(&resource_list);
1253 if (crs_count > 0)
1254 count = crs_count;
1255 }
1256 return count ? count : -ENOENT;
1257 }
1258
1259 bool acpi_can_fallback_to_crs(struct acpi_device *adev, const char *con_id)
1260 {
1261 /* Never allow fallback if the device has properties */
1262 if (acpi_dev_has_props(adev) || adev->driver_gpios)
1263 return false;
1264
1265 return con_id == NULL;
1266 }
1267
1268 /* Run deferred acpi_gpiochip_request_irqs() */
1269 static int acpi_gpio_handle_deferred_request_irqs(void)
1270 {
1271 struct acpi_gpio_chip *acpi_gpio, *tmp;
1272
1273 mutex_lock(&acpi_gpio_deferred_req_irqs_lock);
1274 list_for_each_entry_safe(acpi_gpio, tmp,
1275 &acpi_gpio_deferred_req_irqs_list,
1276 deferred_req_irqs_list_entry)
1277 acpi_gpiochip_request_irqs(acpi_gpio);
1278
1279 acpi_gpio_deferred_req_irqs_done = true;
1280 mutex_unlock(&acpi_gpio_deferred_req_irqs_lock);
1281
1282 return 0;
1283 }
1284 /* We must use _sync so that this runs after the first deferred_probe run */
1285 late_initcall_sync(acpi_gpio_handle_deferred_request_irqs);
Linux with added FPC-III support