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Linux 4.16.11
[linux/fpc-iii.git] / drivers / gpio / gpiolib-acpi.c
blobe2232cbcec8bbe6276e8e9d02e8c0f9e36d34030
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 };
52
53 static int acpi_gpiochip_find(struct gpio_chip *gc, void *data)
54 {
55 if (!gc->parent)
56 return false;
57
58 return ACPI_HANDLE(gc->parent) == data;
59 }
60
61 /**
62 * acpi_get_gpiod() - Translate ACPI GPIO pin to GPIO descriptor usable with GPIO API
63 * @path: ACPI GPIO controller full path name, (e.g. "\\_SB.GPO1")
64 * @pin: ACPI GPIO pin number (0-based, controller-relative)
65 *
66 * Return: GPIO descriptor to use with Linux generic GPIO API, or ERR_PTR
67 * error value. Specifically returns %-EPROBE_DEFER if the referenced GPIO
68 * controller does not have gpiochip registered at the moment. This is to
69 * support probe deferral.
70 */
71 static struct gpio_desc *acpi_get_gpiod(char *path, int pin)
72 {
73 struct gpio_chip *chip;
74 acpi_handle handle;
75 acpi_status status;
76
77 status = acpi_get_handle(NULL, path, &handle);
78 if (ACPI_FAILURE(status))
79 return ERR_PTR(-ENODEV);
80
81 chip = gpiochip_find(handle, acpi_gpiochip_find);
82 if (!chip)
83 return ERR_PTR(-EPROBE_DEFER);
84
85 return gpiochip_get_desc(chip, pin);
86 }
87
88 static irqreturn_t acpi_gpio_irq_handler(int irq, void *data)
89 {
90 struct acpi_gpio_event *event = data;
91
92 acpi_evaluate_object(event->handle, NULL, NULL, NULL);
93
94 return IRQ_HANDLED;
95 }
96
97 static irqreturn_t acpi_gpio_irq_handler_evt(int irq, void *data)
98 {
99 struct acpi_gpio_event *event = data;
100
101 acpi_execute_simple_method(event->handle, NULL, event->pin);
102
103 return IRQ_HANDLED;
104 }
105
106 static void acpi_gpio_chip_dh(acpi_handle handle, void *data)
107 {
108 /* The address of this function is used as a key. */
109 }
110
111 bool acpi_gpio_get_irq_resource(struct acpi_resource *ares,
112 struct acpi_resource_gpio **agpio)
113 {
114 struct acpi_resource_gpio *gpio;
115
116 if (ares->type != ACPI_RESOURCE_TYPE_GPIO)
117 return false;
118
119 gpio = &ares->data.gpio;
120 if (gpio->connection_type != ACPI_RESOURCE_GPIO_TYPE_INT)
121 return false;
122
123 *agpio = gpio;
124 return true;
125 }
126 EXPORT_SYMBOL_GPL(acpi_gpio_get_irq_resource);
127
128 static acpi_status acpi_gpiochip_request_interrupt(struct acpi_resource *ares,
129 void *context)
130 {
131 struct acpi_gpio_chip *acpi_gpio = context;
132 struct gpio_chip *chip = acpi_gpio->chip;
133 struct acpi_resource_gpio *agpio;
134 acpi_handle handle, evt_handle;
135 struct acpi_gpio_event *event;
136 irq_handler_t handler = NULL;
137 struct gpio_desc *desc;
138 unsigned long irqflags;
139 int ret, pin, irq;
140
141 if (!acpi_gpio_get_irq_resource(ares, &agpio))
142 return AE_OK;
143
144 handle = ACPI_HANDLE(chip->parent);
145 pin = agpio->pin_table[0];
146
147 if (pin <= 255) {
148 char ev_name[5];
149 sprintf(ev_name, "_%c%02hhX",
150 agpio->triggering == ACPI_EDGE_SENSITIVE ? 'E' : 'L',
151 pin);
152 if (ACPI_SUCCESS(acpi_get_handle(handle, ev_name, &evt_handle)))
153 handler = acpi_gpio_irq_handler;
154 }
155 if (!handler) {
156 if (ACPI_SUCCESS(acpi_get_handle(handle, "_EVT", &evt_handle)))
157 handler = acpi_gpio_irq_handler_evt;
158 }
159 if (!handler)
160 return AE_OK;
161
162 desc = gpiochip_request_own_desc(chip, pin, "ACPI:Event");
163 if (IS_ERR(desc)) {
164 dev_err(chip->parent, "Failed to request GPIO\n");
165 return AE_ERROR;
166 }
167
168 gpiod_direction_input(desc);
169
170 ret = gpiochip_lock_as_irq(chip, pin);
171 if (ret) {
172 dev_err(chip->parent, "Failed to lock GPIO as interrupt\n");
173 goto fail_free_desc;
174 }
175
176 irq = gpiod_to_irq(desc);
177 if (irq < 0) {
178 dev_err(chip->parent, "Failed to translate GPIO to IRQ\n");
179 goto fail_unlock_irq;
180 }
181
182 irqflags = IRQF_ONESHOT;
183 if (agpio->triggering == ACPI_LEVEL_SENSITIVE) {
184 if (agpio->polarity == ACPI_ACTIVE_HIGH)
185 irqflags |= IRQF_TRIGGER_HIGH;
186 else
187 irqflags |= IRQF_TRIGGER_LOW;
188 } else {
189 switch (agpio->polarity) {
190 case ACPI_ACTIVE_HIGH:
191 irqflags |= IRQF_TRIGGER_RISING;
192 break;
193 case ACPI_ACTIVE_LOW:
194 irqflags |= IRQF_TRIGGER_FALLING;
195 break;
196 default:
197 irqflags |= IRQF_TRIGGER_RISING |
198 IRQF_TRIGGER_FALLING;
199 break;
200 }
201 }
202
203 event = kzalloc(sizeof(*event), GFP_KERNEL);
204 if (!event)
205 goto fail_unlock_irq;
206
207 event->handle = evt_handle;
208 event->irq = irq;
209 event->pin = pin;
210 event->desc = desc;
211
212 ret = request_threaded_irq(event->irq, NULL, handler, irqflags,
213 "ACPI:Event", event);
214 if (ret) {
215 dev_err(chip->parent,
216 "Failed to setup interrupt handler for %d\n",
217 event->irq);
218 goto fail_free_event;
219 }
220
221 if (agpio->wake_capable == ACPI_WAKE_CAPABLE)
222 enable_irq_wake(irq);
223
224 list_add_tail(&event->node, &acpi_gpio->events);
225 return AE_OK;
226
227 fail_free_event:
228 kfree(event);
229 fail_unlock_irq:
230 gpiochip_unlock_as_irq(chip, pin);
231 fail_free_desc:
232 gpiochip_free_own_desc(desc);
233
234 return AE_ERROR;
235 }
236
237 /**
238 * acpi_gpiochip_request_interrupts() - Register isr for gpio chip ACPI events
239 * @chip: GPIO chip
240 *
241 * ACPI5 platforms can use GPIO signaled ACPI events. These GPIO interrupts are
242 * handled by ACPI event methods which need to be called from the GPIO
243 * chip's interrupt handler. acpi_gpiochip_request_interrupts finds out which
244 * gpio pins have acpi event methods and assigns interrupt handlers that calls
245 * the acpi event methods for those pins.
246 */
247 void acpi_gpiochip_request_interrupts(struct gpio_chip *chip)
248 {
249 struct acpi_gpio_chip *acpi_gpio;
250 acpi_handle handle;
251 acpi_status status;
252
253 if (!chip->parent || !chip->to_irq)
254 return;
255
256 handle = ACPI_HANDLE(chip->parent);
257 if (!handle)
258 return;
259
260 status = acpi_get_data(handle, acpi_gpio_chip_dh, (void **)&acpi_gpio);
261 if (ACPI_FAILURE(status))
262 return;
263
264 acpi_walk_resources(handle, "_AEI",
265 acpi_gpiochip_request_interrupt, acpi_gpio);
266 }
267 EXPORT_SYMBOL_GPL(acpi_gpiochip_request_interrupts);
268
269 /**
270 * acpi_gpiochip_free_interrupts() - Free GPIO ACPI event interrupts.
271 * @chip: GPIO chip
272 *
273 * Free interrupts associated with GPIO ACPI event method for the given
274 * GPIO chip.
275 */
276 void acpi_gpiochip_free_interrupts(struct gpio_chip *chip)
277 {
278 struct acpi_gpio_chip *acpi_gpio;
279 struct acpi_gpio_event *event, *ep;
280 acpi_handle handle;
281 acpi_status status;
282
283 if (!chip->parent || !chip->to_irq)
284 return;
285
286 handle = ACPI_HANDLE(chip->parent);
287 if (!handle)
288 return;
289
290 status = acpi_get_data(handle, acpi_gpio_chip_dh, (void **)&acpi_gpio);
291 if (ACPI_FAILURE(status))
292 return;
293
294 list_for_each_entry_safe_reverse(event, ep, &acpi_gpio->events, node) {
295 struct gpio_desc *desc;
296
297 if (irqd_is_wakeup_set(irq_get_irq_data(event->irq)))
298 disable_irq_wake(event->irq);
299
300 free_irq(event->irq, event);
301 desc = event->desc;
302 if (WARN_ON(IS_ERR(desc)))
303 continue;
304 gpiochip_unlock_as_irq(chip, event->pin);
305 gpiochip_free_own_desc(desc);
306 list_del(&event->node);
307 kfree(event);
308 }
309 }
310 EXPORT_SYMBOL_GPL(acpi_gpiochip_free_interrupts);
311
312 int acpi_dev_add_driver_gpios(struct acpi_device *adev,
313 const struct acpi_gpio_mapping *gpios)
314 {
315 if (adev && gpios) {
316 adev->driver_gpios = gpios;
317 return 0;
318 }
319 return -EINVAL;
320 }
321 EXPORT_SYMBOL_GPL(acpi_dev_add_driver_gpios);
322
323 static void devm_acpi_dev_release_driver_gpios(struct device *dev, void *res)
324 {
325 acpi_dev_remove_driver_gpios(ACPI_COMPANION(dev));
326 }
327
328 int devm_acpi_dev_add_driver_gpios(struct device *dev,
329 const struct acpi_gpio_mapping *gpios)
330 {
331 void *res;
332 int ret;
333
334 res = devres_alloc(devm_acpi_dev_release_driver_gpios, 0, GFP_KERNEL);
335 if (!res)
336 return -ENOMEM;
337
338 ret = acpi_dev_add_driver_gpios(ACPI_COMPANION(dev), gpios);
339 if (ret) {
340 devres_free(res);
341 return ret;
342 }
343 devres_add(dev, res);
344 return 0;
345 }
346 EXPORT_SYMBOL_GPL(devm_acpi_dev_add_driver_gpios);
347
348 void devm_acpi_dev_remove_driver_gpios(struct device *dev)
349 {
350 WARN_ON(devres_release(dev, devm_acpi_dev_release_driver_gpios, NULL, NULL));
351 }
352 EXPORT_SYMBOL_GPL(devm_acpi_dev_remove_driver_gpios);
353
354 static bool acpi_get_driver_gpio_data(struct acpi_device *adev,
355 const char *name, int index,
356 struct acpi_reference_args *args,
357 unsigned int *quirks)
358 {
359 const struct acpi_gpio_mapping *gm;
360
361 if (!adev->driver_gpios)
362 return false;
363
364 for (gm = adev->driver_gpios; gm->name; gm++)
365 if (!strcmp(name, gm->name) && gm->data && index < gm->size) {
366 const struct acpi_gpio_params *par = gm->data + index;
367
368 args->adev = adev;
369 args->args[0] = par->crs_entry_index;
370 args->args[1] = par->line_index;
371 args->args[2] = par->active_low;
372 args->nargs = 3;
373
374 *quirks = gm->quirks;
375 return true;
376 }
377
378 return false;
379 }
380
381 static enum gpiod_flags
382 acpi_gpio_to_gpiod_flags(const struct acpi_resource_gpio *agpio)
383 {
384 bool pull_up = agpio->pin_config == ACPI_PIN_CONFIG_PULLUP;
385
386 switch (agpio->io_restriction) {
387 case ACPI_IO_RESTRICT_INPUT:
388 return GPIOD_IN;
389 case ACPI_IO_RESTRICT_OUTPUT:
390 /*
391 * ACPI GPIO resources don't contain an initial value for the
392 * GPIO. Therefore we deduce that value from the pull field
393 * instead. If the pin is pulled up we assume default to be
394 * high, otherwise low.
395 */
396 return pull_up ? GPIOD_OUT_HIGH : GPIOD_OUT_LOW;
397 default:
398 /*
399 * Assume that the BIOS has configured the direction and pull
400 * accordingly.
401 */
402 return GPIOD_ASIS;
403 }
404 }
405
406 static int
407 __acpi_gpio_update_gpiod_flags(enum gpiod_flags *flags, enum gpiod_flags update)
408 {
409 int ret = 0;
410
411 /*
412 * Check if the BIOS has IoRestriction with explicitly set direction
413 * and update @flags accordingly. Otherwise use whatever caller asked
414 * for.
415 */
416 if (update & GPIOD_FLAGS_BIT_DIR_SET) {
417 enum gpiod_flags diff = *flags ^ update;
418
419 /*
420 * Check if caller supplied incompatible GPIO initialization
421 * flags.
422 *
423 * Return %-EINVAL to notify that firmware has different
424 * settings and we are going to use them.
425 */
426 if (((*flags & GPIOD_FLAGS_BIT_DIR_SET) && (diff & GPIOD_FLAGS_BIT_DIR_OUT)) ||
427 ((*flags & GPIOD_FLAGS_BIT_DIR_OUT) && (diff & GPIOD_FLAGS_BIT_DIR_VAL)))
428 ret = -EINVAL;
429 *flags = update;
430 }
431 return ret;
432 }
433
434 int
435 acpi_gpio_update_gpiod_flags(enum gpiod_flags *flags, struct acpi_gpio_info *info)
436 {
437 struct device *dev = &info->adev->dev;
438 enum gpiod_flags old = *flags;
439 int ret;
440
441 ret = __acpi_gpio_update_gpiod_flags(&old, info->flags);
442 if (info->quirks & ACPI_GPIO_QUIRK_NO_IO_RESTRICTION) {
443 if (ret)
444 dev_warn(dev, FW_BUG "GPIO not in correct mode, fixing\n");
445 } else {
446 if (ret)
447 dev_dbg(dev, "Override GPIO initialization flags\n");
448 *flags = old;
449 }
450
451 return ret;
452 }
453
454 struct acpi_gpio_lookup {
455 struct acpi_gpio_info info;
456 int index;
457 int pin_index;
458 bool active_low;
459 struct gpio_desc *desc;
460 int n;
461 };
462
463 static int acpi_populate_gpio_lookup(struct acpi_resource *ares, void *data)
464 {
465 struct acpi_gpio_lookup *lookup = data;
466
467 if (ares->type != ACPI_RESOURCE_TYPE_GPIO)
468 return 1;
469
470 if (lookup->n++ == lookup->index && !lookup->desc) {
471 const struct acpi_resource_gpio *agpio = &ares->data.gpio;
472 int pin_index = lookup->pin_index;
473
474 if (pin_index >= agpio->pin_table_length)
475 return 1;
476
477 lookup->desc = acpi_get_gpiod(agpio->resource_source.string_ptr,
478 agpio->pin_table[pin_index]);
479 lookup->info.gpioint =
480 agpio->connection_type == ACPI_RESOURCE_GPIO_TYPE_INT;
481
482 /*
483 * Polarity and triggering are only specified for GpioInt
484 * resource.
485 * Note: we expect here:
486 * - ACPI_ACTIVE_LOW == GPIO_ACTIVE_LOW
487 * - ACPI_ACTIVE_HIGH == GPIO_ACTIVE_HIGH
488 */
489 if (lookup->info.gpioint) {
490 lookup->info.flags = GPIOD_IN;
491 lookup->info.polarity = agpio->polarity;
492 lookup->info.triggering = agpio->triggering;
493 } else {
494 lookup->info.flags = acpi_gpio_to_gpiod_flags(agpio);
495 lookup->info.polarity = lookup->active_low;
496 }
497 }
498
499 return 1;
500 }
501
502 static int acpi_gpio_resource_lookup(struct acpi_gpio_lookup *lookup,
503 struct acpi_gpio_info *info)
504 {
505 struct acpi_device *adev = lookup->info.adev;
506 struct list_head res_list;
507 int ret;
508
509 INIT_LIST_HEAD(&res_list);
510
511 ret = acpi_dev_get_resources(adev, &res_list,
512 acpi_populate_gpio_lookup,
513 lookup);
514 if (ret < 0)
515 return ret;
516
517 acpi_dev_free_resource_list(&res_list);
518
519 if (!lookup->desc)
520 return -ENOENT;
521
522 if (info)
523 *info = lookup->info;
524 return 0;
525 }
526
527 static int acpi_gpio_property_lookup(struct fwnode_handle *fwnode,
528 const char *propname, int index,
529 struct acpi_gpio_lookup *lookup)
530 {
531 struct acpi_reference_args args;
532 unsigned int quirks = 0;
533 int ret;
534
535 memset(&args, 0, sizeof(args));
536 ret = __acpi_node_get_property_reference(fwnode, propname, index, 3,
537 &args);
538 if (ret) {
539 struct acpi_device *adev = to_acpi_device_node(fwnode);
540
541 if (!adev)
542 return ret;
543
544 if (!acpi_get_driver_gpio_data(adev, propname, index, &args,
545 &quirks))
546 return ret;
547 }
548 /*
549 * The property was found and resolved, so need to lookup the GPIO based
550 * on returned args.
551 */
552 if (args.nargs != 3)
553 return -EPROTO;
554
555 lookup->index = args.args[0];
556 lookup->pin_index = args.args[1];
557 lookup->active_low = !!args.args[2];
558
559 lookup->info.adev = args.adev;
560 lookup->info.quirks = quirks;
561 return 0;
562 }
563
564 /**
565 * acpi_get_gpiod_by_index() - get a GPIO descriptor from device resources
566 * @adev: pointer to a ACPI device to get GPIO from
567 * @propname: Property name of the GPIO (optional)
568 * @index: index of GpioIo/GpioInt resource (starting from %0)
569 * @info: info pointer to fill in (optional)
570 *
571 * Function goes through ACPI resources for @adev and based on @index looks
572 * up a GpioIo/GpioInt resource, translates it to the Linux GPIO descriptor,
573 * and returns it. @index matches GpioIo/GpioInt resources only so if there
574 * are total %3 GPIO resources, the index goes from %0 to %2.
575 *
576 * If @propname is specified the GPIO is looked using device property. In
577 * that case @index is used to select the GPIO entry in the property value
578 * (in case of multiple).
579 *
580 * If the GPIO cannot be translated or there is an error an ERR_PTR is
581 * returned.
582 *
583 * Note: if the GPIO resource has multiple entries in the pin list, this
584 * function only returns the first.
585 */
586 static struct gpio_desc *acpi_get_gpiod_by_index(struct acpi_device *adev,
587 const char *propname, int index,
588 struct acpi_gpio_info *info)
589 {
590 struct acpi_gpio_lookup lookup;
591 int ret;
592
593 if (!adev)
594 return ERR_PTR(-ENODEV);
595
596 memset(&lookup, 0, sizeof(lookup));
597 lookup.index = index;
598
599 if (propname) {
600 dev_dbg(&adev->dev, "GPIO: looking up %s\n", propname);
601
602 ret = acpi_gpio_property_lookup(acpi_fwnode_handle(adev),
603 propname, index, &lookup);
604 if (ret)
605 return ERR_PTR(ret);
606
607 dev_dbg(&adev->dev, "GPIO: _DSD returned %s %d %d %u\n",
608 dev_name(&lookup.info.adev->dev), lookup.index,
609 lookup.pin_index, lookup.active_low);
610 } else {
611 dev_dbg(&adev->dev, "GPIO: looking up %d in _CRS\n", index);
612 lookup.info.adev = adev;
613 }
614
615 ret = acpi_gpio_resource_lookup(&lookup, info);
616 return ret ? ERR_PTR(ret) : lookup.desc;
617 }
618
619 struct gpio_desc *acpi_find_gpio(struct device *dev,
620 const char *con_id,
621 unsigned int idx,
622 enum gpiod_flags *dflags,
623 enum gpio_lookup_flags *lookupflags)
624 {
625 struct acpi_device *adev = ACPI_COMPANION(dev);
626 struct acpi_gpio_info info;
627 struct gpio_desc *desc;
628 char propname[32];
629 int i;
630
631 /* Try first from _DSD */
632 for (i = 0; i < ARRAY_SIZE(gpio_suffixes); i++) {
633 if (con_id) {
634 snprintf(propname, sizeof(propname), "%s-%s",
635 con_id, gpio_suffixes[i]);
636 } else {
637 snprintf(propname, sizeof(propname), "%s",
638 gpio_suffixes[i]);
639 }
640
641 desc = acpi_get_gpiod_by_index(adev, propname, idx, &info);
642 if (!IS_ERR(desc))
643 break;
644 if (PTR_ERR(desc) == -EPROBE_DEFER)
645 return ERR_CAST(desc);
646 }
647
648 /* Then from plain _CRS GPIOs */
649 if (IS_ERR(desc)) {
650 if (!acpi_can_fallback_to_crs(adev, con_id))
651 return ERR_PTR(-ENOENT);
652
653 desc = acpi_get_gpiod_by_index(adev, NULL, idx, &info);
654 if (IS_ERR(desc))
655 return desc;
656 }
657
658 if (info.gpioint &&
659 (*dflags == GPIOD_OUT_LOW || *dflags == GPIOD_OUT_HIGH)) {
660 dev_dbg(dev, "refusing GpioInt() entry when doing GPIOD_OUT_* lookup\n");
661 return ERR_PTR(-ENOENT);
662 }
663
664 if (info.polarity == GPIO_ACTIVE_LOW)
665 *lookupflags |= GPIO_ACTIVE_LOW;
666
667 acpi_gpio_update_gpiod_flags(dflags, &info);
668 return desc;
669 }
670
671 /**
672 * acpi_node_get_gpiod() - get a GPIO descriptor from ACPI resources
673 * @fwnode: pointer to an ACPI firmware node to get the GPIO information from
674 * @propname: Property name of the GPIO
675 * @index: index of GpioIo/GpioInt resource (starting from %0)
676 * @info: info pointer to fill in (optional)
677 *
678 * If @fwnode is an ACPI device object, call %acpi_get_gpiod_by_index() for it.
679 * Otherwise (ie. it is a data-only non-device object), use the property-based
680 * GPIO lookup to get to the GPIO resource with the relevant information and use
681 * that to obtain the GPIO descriptor to return.
682 */
683 struct gpio_desc *acpi_node_get_gpiod(struct fwnode_handle *fwnode,
684 const char *propname, int index,
685 struct acpi_gpio_info *info)
686 {
687 struct acpi_gpio_lookup lookup;
688 struct acpi_device *adev;
689 int ret;
690
691 adev = to_acpi_device_node(fwnode);
692 if (adev)
693 return acpi_get_gpiod_by_index(adev, propname, index, info);
694
695 if (!is_acpi_data_node(fwnode))
696 return ERR_PTR(-ENODEV);
697
698 if (!propname)
699 return ERR_PTR(-EINVAL);
700
701 memset(&lookup, 0, sizeof(lookup));
702 lookup.index = index;
703
704 ret = acpi_gpio_property_lookup(fwnode, propname, index, &lookup);
705 if (ret)
706 return ERR_PTR(ret);
707
708 ret = acpi_gpio_resource_lookup(&lookup, info);
709 return ret ? ERR_PTR(ret) : lookup.desc;
710 }
711
712 /**
713 * acpi_dev_gpio_irq_get() - Find GpioInt and translate it to Linux IRQ number
714 * @adev: pointer to a ACPI device to get IRQ from
715 * @index: index of GpioInt resource (starting from %0)
716 *
717 * If the device has one or more GpioInt resources, this function can be
718 * used to translate from the GPIO offset in the resource to the Linux IRQ
719 * number.
720 *
721 * The function is idempotent, though each time it runs it will configure GPIO
722 * pin direction according to the flags in GpioInt resource.
723 *
724 * Return: Linux IRQ number (> %0) on success, negative errno on failure.
725 */
726 int acpi_dev_gpio_irq_get(struct acpi_device *adev, int index)
727 {
728 int idx, i;
729 unsigned int irq_flags;
730 int ret;
731
732 for (i = 0, idx = 0; idx <= index; i++) {
733 struct acpi_gpio_info info;
734 struct gpio_desc *desc;
735
736 desc = acpi_get_gpiod_by_index(adev, NULL, i, &info);
737
738 /* Ignore -EPROBE_DEFER, it only matters if idx matches */
739 if (IS_ERR(desc) && PTR_ERR(desc) != -EPROBE_DEFER)
740 return PTR_ERR(desc);
741
742 if (info.gpioint && idx++ == index) {
743 char label[32];
744 int irq;
745
746 if (IS_ERR(desc))
747 return PTR_ERR(desc);
748
749 irq = gpiod_to_irq(desc);
750 if (irq < 0)
751 return irq;
752
753 snprintf(label, sizeof(label), "GpioInt() %d", index);
754 ret = gpiod_configure_flags(desc, label, 0, info.flags);
755 if (ret < 0)
756 return ret;
757
758 irq_flags = acpi_dev_get_irq_type(info.triggering,
759 info.polarity);
760
761 /* Set type if specified and different than the current one */
762 if (irq_flags != IRQ_TYPE_NONE &&
763 irq_flags != irq_get_trigger_type(irq))
764 irq_set_irq_type(irq, irq_flags);
765
766 return irq;
767 }
768
769 }
770 return -ENOENT;
771 }
772 EXPORT_SYMBOL_GPL(acpi_dev_gpio_irq_get);
773
774 static acpi_status
775 acpi_gpio_adr_space_handler(u32 function, acpi_physical_address address,
776 u32 bits, u64 *value, void *handler_context,
777 void *region_context)
778 {
779 struct acpi_gpio_chip *achip = region_context;
780 struct gpio_chip *chip = achip->chip;
781 struct acpi_resource_gpio *agpio;
782 struct acpi_resource *ares;
783 int pin_index = (int)address;
784 acpi_status status;
785 int length;
786 int i;
787
788 status = acpi_buffer_to_resource(achip->conn_info.connection,
789 achip->conn_info.length, &ares);
790 if (ACPI_FAILURE(status))
791 return status;
792
793 if (WARN_ON(ares->type != ACPI_RESOURCE_TYPE_GPIO)) {
794 ACPI_FREE(ares);
795 return AE_BAD_PARAMETER;
796 }
797
798 agpio = &ares->data.gpio;
799
800 if (WARN_ON(agpio->io_restriction == ACPI_IO_RESTRICT_INPUT &&
801 function == ACPI_WRITE)) {
802 ACPI_FREE(ares);
803 return AE_BAD_PARAMETER;
804 }
805
806 length = min(agpio->pin_table_length, (u16)(pin_index + bits));
807 for (i = pin_index; i < length; ++i) {
808 int pin = agpio->pin_table[i];
809 struct acpi_gpio_connection *conn;
810 struct gpio_desc *desc;
811 bool found;
812
813 mutex_lock(&achip->conn_lock);
814
815 found = false;
816 list_for_each_entry(conn, &achip->conns, node) {
817 if (conn->pin == pin) {
818 found = true;
819 desc = conn->desc;
820 break;
821 }
822 }
823
824 /*
825 * The same GPIO can be shared between operation region and
826 * event but only if the access here is ACPI_READ. In that
827 * case we "borrow" the event GPIO instead.
828 */
829 if (!found && agpio->sharable == ACPI_SHARED &&
830 function == ACPI_READ) {
831 struct acpi_gpio_event *event;
832
833 list_for_each_entry(event, &achip->events, node) {
834 if (event->pin == pin) {
835 desc = event->desc;
836 found = true;
837 break;
838 }
839 }
840 }
841
842 if (!found) {
843 enum gpiod_flags flags = acpi_gpio_to_gpiod_flags(agpio);
844 const char *label = "ACPI:OpRegion";
845 int err;
846
847 desc = gpiochip_request_own_desc(chip, pin, label);
848 if (IS_ERR(desc)) {
849 status = AE_ERROR;
850 mutex_unlock(&achip->conn_lock);
851 goto out;
852 }
853
854 err = gpiod_configure_flags(desc, label, 0, flags);
855 if (err < 0) {
856 status = AE_NOT_CONFIGURED;
857 gpiochip_free_own_desc(desc);
858 mutex_unlock(&achip->conn_lock);
859 goto out;
860 }
861
862 conn = kzalloc(sizeof(*conn), GFP_KERNEL);
863 if (!conn) {
864 status = AE_NO_MEMORY;
865 gpiochip_free_own_desc(desc);
866 mutex_unlock(&achip->conn_lock);
867 goto out;
868 }
869
870 conn->pin = pin;
871 conn->desc = desc;
872 list_add_tail(&conn->node, &achip->conns);
873 }
874
875 mutex_unlock(&achip->conn_lock);
876
877 if (function == ACPI_WRITE)
878 gpiod_set_raw_value_cansleep(desc,
879 !!((1 << i) & *value));
880 else
881 *value |= (u64)gpiod_get_raw_value_cansleep(desc) << i;
882 }
883
884 out:
885 ACPI_FREE(ares);
886 return status;
887 }
888
889 static void acpi_gpiochip_request_regions(struct acpi_gpio_chip *achip)
890 {
891 struct gpio_chip *chip = achip->chip;
892 acpi_handle handle = ACPI_HANDLE(chip->parent);
893 acpi_status status;
894
895 INIT_LIST_HEAD(&achip->conns);
896 mutex_init(&achip->conn_lock);
897 status = acpi_install_address_space_handler(handle, ACPI_ADR_SPACE_GPIO,
898 acpi_gpio_adr_space_handler,
899 NULL, achip);
900 if (ACPI_FAILURE(status))
901 dev_err(chip->parent,
902 "Failed to install GPIO OpRegion handler\n");
903 }
904
905 static void acpi_gpiochip_free_regions(struct acpi_gpio_chip *achip)
906 {
907 struct gpio_chip *chip = achip->chip;
908 acpi_handle handle = ACPI_HANDLE(chip->parent);
909 struct acpi_gpio_connection *conn, *tmp;
910 acpi_status status;
911
912 status = acpi_remove_address_space_handler(handle, ACPI_ADR_SPACE_GPIO,
913 acpi_gpio_adr_space_handler);
914 if (ACPI_FAILURE(status)) {
915 dev_err(chip->parent,
916 "Failed to remove GPIO OpRegion handler\n");
917 return;
918 }
919
920 list_for_each_entry_safe_reverse(conn, tmp, &achip->conns, node) {
921 gpiochip_free_own_desc(conn->desc);
922 list_del(&conn->node);
923 kfree(conn);
924 }
925 }
926
927 static struct gpio_desc *acpi_gpiochip_parse_own_gpio(
928 struct acpi_gpio_chip *achip, struct fwnode_handle *fwnode,
929 const char **name, unsigned int *lflags, unsigned int *dflags)
930 {
931 struct gpio_chip *chip = achip->chip;
932 struct gpio_desc *desc;
933 u32 gpios[2];
934 int ret;
935
936 *lflags = 0;
937 *dflags = 0;
938 *name = NULL;
939
940 ret = fwnode_property_read_u32_array(fwnode, "gpios", gpios,
941 ARRAY_SIZE(gpios));
942 if (ret < 0)
943 return ERR_PTR(ret);
944
945 desc = gpiochip_get_desc(chip, gpios[0]);
946 if (IS_ERR(desc))
947 return desc;
948
949 if (gpios[1])
950 *lflags |= GPIO_ACTIVE_LOW;
951
952 if (fwnode_property_present(fwnode, "input"))
953 *dflags |= GPIOD_IN;
954 else if (fwnode_property_present(fwnode, "output-low"))
955 *dflags |= GPIOD_OUT_LOW;
956 else if (fwnode_property_present(fwnode, "output-high"))
957 *dflags |= GPIOD_OUT_HIGH;
958 else
959 return ERR_PTR(-EINVAL);
960
961 fwnode_property_read_string(fwnode, "line-name", name);
962
963 return desc;
964 }
965
966 static void acpi_gpiochip_scan_gpios(struct acpi_gpio_chip *achip)
967 {
968 struct gpio_chip *chip = achip->chip;
969 struct fwnode_handle *fwnode;
970
971 device_for_each_child_node(chip->parent, fwnode) {
972 unsigned int lflags, dflags;
973 struct gpio_desc *desc;
974 const char *name;
975 int ret;
976
977 if (!fwnode_property_present(fwnode, "gpio-hog"))
978 continue;
979
980 desc = acpi_gpiochip_parse_own_gpio(achip, fwnode, &name,
981 &lflags, &dflags);
982 if (IS_ERR(desc))
983 continue;
984
985 ret = gpiod_hog(desc, name, lflags, dflags);
986 if (ret) {
987 dev_err(chip->parent, "Failed to hog GPIO\n");
988 fwnode_handle_put(fwnode);
989 return;
990 }
991 }
992 }
993
994 void acpi_gpiochip_add(struct gpio_chip *chip)
995 {
996 struct acpi_gpio_chip *acpi_gpio;
997 acpi_handle handle;
998 acpi_status status;
999
1000 if (!chip || !chip->parent)
1001 return;
1002
1003 handle = ACPI_HANDLE(chip->parent);
1004 if (!handle)
1005 return;
1006
1007 acpi_gpio = kzalloc(sizeof(*acpi_gpio), GFP_KERNEL);
1008 if (!acpi_gpio) {
1009 dev_err(chip->parent,
1010 "Failed to allocate memory for ACPI GPIO chip\n");
1011 return;
1012 }
1013
1014 acpi_gpio->chip = chip;
1015 INIT_LIST_HEAD(&acpi_gpio->events);
1016
1017 status = acpi_attach_data(handle, acpi_gpio_chip_dh, acpi_gpio);
1018 if (ACPI_FAILURE(status)) {
1019 dev_err(chip->parent, "Failed to attach ACPI GPIO chip\n");
1020 kfree(acpi_gpio);
1021 return;
1022 }
1023
1024 if (!chip->names)
1025 devprop_gpiochip_set_names(chip, dev_fwnode(chip->parent));
1026
1027 acpi_gpiochip_request_regions(acpi_gpio);
1028 acpi_gpiochip_scan_gpios(acpi_gpio);
1029 acpi_walk_dep_device_list(handle);
1030 }
1031
1032 void acpi_gpiochip_remove(struct gpio_chip *chip)
1033 {
1034 struct acpi_gpio_chip *acpi_gpio;
1035 acpi_handle handle;
1036 acpi_status status;
1037
1038 if (!chip || !chip->parent)
1039 return;
1040
1041 handle = ACPI_HANDLE(chip->parent);
1042 if (!handle)
1043 return;
1044
1045 status = acpi_get_data(handle, acpi_gpio_chip_dh, (void **)&acpi_gpio);
1046 if (ACPI_FAILURE(status)) {
1047 dev_warn(chip->parent, "Failed to retrieve ACPI GPIO chip\n");
1048 return;
1049 }
1050
1051 acpi_gpiochip_free_regions(acpi_gpio);
1052
1053 acpi_detach_data(handle, acpi_gpio_chip_dh);
1054 kfree(acpi_gpio);
1055 }
1056
1057 static int acpi_gpio_package_count(const union acpi_object *obj)
1058 {
1059 const union acpi_object *element = obj->package.elements;
1060 const union acpi_object *end = element + obj->package.count;
1061 unsigned int count = 0;
1062
1063 while (element < end) {
1064 switch (element->type) {
1065 case ACPI_TYPE_LOCAL_REFERENCE:
1066 element += 3;
1067 /* Fallthrough */
1068 case ACPI_TYPE_INTEGER:
1069 element++;
1070 count++;
1071 break;
1072
1073 default:
1074 return -EPROTO;
1075 }
1076 }
1077
1078 return count;
1079 }
1080
1081 static int acpi_find_gpio_count(struct acpi_resource *ares, void *data)
1082 {
1083 unsigned int *count = data;
1084
1085 if (ares->type == ACPI_RESOURCE_TYPE_GPIO)
1086 *count += ares->data.gpio.pin_table_length;
1087
1088 return 1;
1089 }
1090
1091 /**
1092 * acpi_gpio_count - return the number of GPIOs associated with a
1093 * device / function or -ENOENT if no GPIO has been
1094 * assigned to the requested function.
1095 * @dev: GPIO consumer, can be NULL for system-global GPIOs
1096 * @con_id: function within the GPIO consumer
1097 */
1098 int acpi_gpio_count(struct device *dev, const char *con_id)
1099 {
1100 struct acpi_device *adev = ACPI_COMPANION(dev);
1101 const union acpi_object *obj;
1102 const struct acpi_gpio_mapping *gm;
1103 int count = -ENOENT;
1104 int ret;
1105 char propname[32];
1106 unsigned int i;
1107
1108 /* Try first from _DSD */
1109 for (i = 0; i < ARRAY_SIZE(gpio_suffixes); i++) {
1110 if (con_id)
1111 snprintf(propname, sizeof(propname), "%s-%s",
1112 con_id, gpio_suffixes[i]);
1113 else
1114 snprintf(propname, sizeof(propname), "%s",
1115 gpio_suffixes[i]);
1116
1117 ret = acpi_dev_get_property(adev, propname, ACPI_TYPE_ANY,
1118 &obj);
1119 if (ret == 0) {
1120 if (obj->type == ACPI_TYPE_LOCAL_REFERENCE)
1121 count = 1;
1122 else if (obj->type == ACPI_TYPE_PACKAGE)
1123 count = acpi_gpio_package_count(obj);
1124 } else if (adev->driver_gpios) {
1125 for (gm = adev->driver_gpios; gm->name; gm++)
1126 if (strcmp(propname, gm->name) == 0) {
1127 count = gm->size;
1128 break;
1129 }
1130 }
1131 if (count > 0)
1132 break;
1133 }
1134
1135 /* Then from plain _CRS GPIOs */
1136 if (count < 0) {
1137 struct list_head resource_list;
1138 unsigned int crs_count = 0;
1139
1140 if (!acpi_can_fallback_to_crs(adev, con_id))
1141 return count;
1142
1143 INIT_LIST_HEAD(&resource_list);
1144 acpi_dev_get_resources(adev, &resource_list,
1145 acpi_find_gpio_count, &crs_count);
1146 acpi_dev_free_resource_list(&resource_list);
1147 if (crs_count > 0)
1148 count = crs_count;
1149 }
1150 return count ? count : -ENOENT;
1151 }
1152
1153 bool acpi_can_fallback_to_crs(struct acpi_device *adev, const char *con_id)
1154 {
1155 /* Never allow fallback if the device has properties */
1156 if (adev->data.properties || adev->driver_gpios)
1157 return false;
1158
1159 return con_id == NULL;
1160 }
Linux with added FPC-III support