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Merge 4.13-rc2 into tty-next
[linux/fpc-iii.git] / drivers / gpio / gpiolib-acpi.c
blobc9b42dd12dfad1bd5528f6519bd7960547c510c8
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 #ifdef CONFIG_PINCTRL
62 /**
63 * acpi_gpiochip_pin_to_gpio_offset() - translates ACPI GPIO to Linux GPIO
64 * @chip: GPIO chip
65 * @pin: ACPI GPIO pin number from GpioIo/GpioInt resource
66 *
67 * Function takes ACPI GpioIo/GpioInt pin number as a parameter and
68 * translates it to a corresponding offset suitable to be passed to a
69 * GPIO controller driver.
70 *
71 * Typically the returned offset is same as @pin, but if the GPIO
72 * controller uses pin controller and the mapping is not contiguous the
73 * offset might be different.
74 */
75 static int acpi_gpiochip_pin_to_gpio_offset(struct gpio_device *gdev, int pin)
76 {
77 struct gpio_pin_range *pin_range;
78
79 /* If there are no ranges in this chip, use 1:1 mapping */
80 if (list_empty(&gdev->pin_ranges))
81 return pin;
82
83 list_for_each_entry(pin_range, &gdev->pin_ranges, node) {
84 const struct pinctrl_gpio_range *range = &pin_range->range;
85 int i;
86
87 if (range->pins) {
88 for (i = 0; i < range->npins; i++) {
89 if (range->pins[i] == pin)
90 return range->base + i - gdev->base;
91 }
92 } else {
93 if (pin >= range->pin_base &&
94 pin < range->pin_base + range->npins) {
95 unsigned gpio_base;
96
97 gpio_base = range->base - gdev->base;
98 return gpio_base + pin - range->pin_base;
99 }
100 }
101 }
102
103 return -EINVAL;
104 }
105 #else
106 static inline int acpi_gpiochip_pin_to_gpio_offset(struct gpio_device *gdev,
107 int pin)
108 {
109 return pin;
110 }
111 #endif
112
113 /**
114 * acpi_get_gpiod() - Translate ACPI GPIO pin to GPIO descriptor usable with GPIO API
115 * @path: ACPI GPIO controller full path name, (e.g. "\\_SB.GPO1")
116 * @pin: ACPI GPIO pin number (0-based, controller-relative)
117 *
118 * Return: GPIO descriptor to use with Linux generic GPIO API, or ERR_PTR
119 * error value. Specifically returns %-EPROBE_DEFER if the referenced GPIO
120 * controller does not have gpiochip registered at the moment. This is to
121 * support probe deferral.
122 */
123 static struct gpio_desc *acpi_get_gpiod(char *path, int pin)
124 {
125 struct gpio_chip *chip;
126 acpi_handle handle;
127 acpi_status status;
128 int offset;
129
130 status = acpi_get_handle(NULL, path, &handle);
131 if (ACPI_FAILURE(status))
132 return ERR_PTR(-ENODEV);
133
134 chip = gpiochip_find(handle, acpi_gpiochip_find);
135 if (!chip)
136 return ERR_PTR(-EPROBE_DEFER);
137
138 offset = acpi_gpiochip_pin_to_gpio_offset(chip->gpiodev, pin);
139 if (offset < 0)
140 return ERR_PTR(offset);
141
142 return gpiochip_get_desc(chip, offset);
143 }
144
145 static irqreturn_t acpi_gpio_irq_handler(int irq, void *data)
146 {
147 struct acpi_gpio_event *event = data;
148
149 acpi_evaluate_object(event->handle, NULL, NULL, NULL);
150
151 return IRQ_HANDLED;
152 }
153
154 static irqreturn_t acpi_gpio_irq_handler_evt(int irq, void *data)
155 {
156 struct acpi_gpio_event *event = data;
157
158 acpi_execute_simple_method(event->handle, NULL, event->pin);
159
160 return IRQ_HANDLED;
161 }
162
163 static void acpi_gpio_chip_dh(acpi_handle handle, void *data)
164 {
165 /* The address of this function is used as a key. */
166 }
167
168 bool acpi_gpio_get_irq_resource(struct acpi_resource *ares,
169 struct acpi_resource_gpio **agpio)
170 {
171 struct acpi_resource_gpio *gpio;
172
173 if (ares->type != ACPI_RESOURCE_TYPE_GPIO)
174 return false;
175
176 gpio = &ares->data.gpio;
177 if (gpio->connection_type != ACPI_RESOURCE_GPIO_TYPE_INT)
178 return false;
179
180 *agpio = gpio;
181 return true;
182 }
183 EXPORT_SYMBOL_GPL(acpi_gpio_get_irq_resource);
184
185 static acpi_status acpi_gpiochip_request_interrupt(struct acpi_resource *ares,
186 void *context)
187 {
188 struct acpi_gpio_chip *acpi_gpio = context;
189 struct gpio_chip *chip = acpi_gpio->chip;
190 struct acpi_resource_gpio *agpio;
191 acpi_handle handle, evt_handle;
192 struct acpi_gpio_event *event;
193 irq_handler_t handler = NULL;
194 struct gpio_desc *desc;
195 unsigned long irqflags;
196 int ret, pin, irq;
197
198 if (!acpi_gpio_get_irq_resource(ares, &agpio))
199 return AE_OK;
200
201 handle = ACPI_HANDLE(chip->parent);
202 pin = agpio->pin_table[0];
203
204 if (pin <= 255) {
205 char ev_name[5];
206 sprintf(ev_name, "_%c%02X",
207 agpio->triggering == ACPI_EDGE_SENSITIVE ? 'E' : 'L',
208 pin);
209 if (ACPI_SUCCESS(acpi_get_handle(handle, ev_name, &evt_handle)))
210 handler = acpi_gpio_irq_handler;
211 }
212 if (!handler) {
213 if (ACPI_SUCCESS(acpi_get_handle(handle, "_EVT", &evt_handle)))
214 handler = acpi_gpio_irq_handler_evt;
215 }
216 if (!handler)
217 return AE_OK;
218
219 pin = acpi_gpiochip_pin_to_gpio_offset(chip->gpiodev, pin);
220 if (pin < 0)
221 return AE_BAD_PARAMETER;
222
223 desc = gpiochip_request_own_desc(chip, pin, "ACPI:Event");
224 if (IS_ERR(desc)) {
225 dev_err(chip->parent, "Failed to request GPIO\n");
226 return AE_ERROR;
227 }
228
229 gpiod_direction_input(desc);
230
231 ret = gpiochip_lock_as_irq(chip, pin);
232 if (ret) {
233 dev_err(chip->parent, "Failed to lock GPIO as interrupt\n");
234 goto fail_free_desc;
235 }
236
237 irq = gpiod_to_irq(desc);
238 if (irq < 0) {
239 dev_err(chip->parent, "Failed to translate GPIO to IRQ\n");
240 goto fail_unlock_irq;
241 }
242
243 irqflags = IRQF_ONESHOT;
244 if (agpio->triggering == ACPI_LEVEL_SENSITIVE) {
245 if (agpio->polarity == ACPI_ACTIVE_HIGH)
246 irqflags |= IRQF_TRIGGER_HIGH;
247 else
248 irqflags |= IRQF_TRIGGER_LOW;
249 } else {
250 switch (agpio->polarity) {
251 case ACPI_ACTIVE_HIGH:
252 irqflags |= IRQF_TRIGGER_RISING;
253 break;
254 case ACPI_ACTIVE_LOW:
255 irqflags |= IRQF_TRIGGER_FALLING;
256 break;
257 default:
258 irqflags |= IRQF_TRIGGER_RISING |
259 IRQF_TRIGGER_FALLING;
260 break;
261 }
262 }
263
264 event = kzalloc(sizeof(*event), GFP_KERNEL);
265 if (!event)
266 goto fail_unlock_irq;
267
268 event->handle = evt_handle;
269 event->irq = irq;
270 event->pin = pin;
271 event->desc = desc;
272
273 ret = request_threaded_irq(event->irq, NULL, handler, irqflags,
274 "ACPI:Event", event);
275 if (ret) {
276 dev_err(chip->parent,
277 "Failed to setup interrupt handler for %d\n",
278 event->irq);
279 goto fail_free_event;
280 }
281
282 if (agpio->wake_capable == ACPI_WAKE_CAPABLE)
283 enable_irq_wake(irq);
284
285 list_add_tail(&event->node, &acpi_gpio->events);
286 return AE_OK;
287
288 fail_free_event:
289 kfree(event);
290 fail_unlock_irq:
291 gpiochip_unlock_as_irq(chip, pin);
292 fail_free_desc:
293 gpiochip_free_own_desc(desc);
294
295 return AE_ERROR;
296 }
297
298 /**
299 * acpi_gpiochip_request_interrupts() - Register isr for gpio chip ACPI events
300 * @chip: GPIO chip
301 *
302 * ACPI5 platforms can use GPIO signaled ACPI events. These GPIO interrupts are
303 * handled by ACPI event methods which need to be called from the GPIO
304 * chip's interrupt handler. acpi_gpiochip_request_interrupts finds out which
305 * gpio pins have acpi event methods and assigns interrupt handlers that calls
306 * the acpi event methods for those pins.
307 */
308 void acpi_gpiochip_request_interrupts(struct gpio_chip *chip)
309 {
310 struct acpi_gpio_chip *acpi_gpio;
311 acpi_handle handle;
312 acpi_status status;
313
314 if (!chip->parent || !chip->to_irq)
315 return;
316
317 handle = ACPI_HANDLE(chip->parent);
318 if (!handle)
319 return;
320
321 status = acpi_get_data(handle, acpi_gpio_chip_dh, (void **)&acpi_gpio);
322 if (ACPI_FAILURE(status))
323 return;
324
325 acpi_walk_resources(handle, "_AEI",
326 acpi_gpiochip_request_interrupt, acpi_gpio);
327 }
328 EXPORT_SYMBOL_GPL(acpi_gpiochip_request_interrupts);
329
330 /**
331 * acpi_gpiochip_free_interrupts() - Free GPIO ACPI event interrupts.
332 * @chip: GPIO chip
333 *
334 * Free interrupts associated with GPIO ACPI event method for the given
335 * GPIO chip.
336 */
337 void acpi_gpiochip_free_interrupts(struct gpio_chip *chip)
338 {
339 struct acpi_gpio_chip *acpi_gpio;
340 struct acpi_gpio_event *event, *ep;
341 acpi_handle handle;
342 acpi_status status;
343
344 if (!chip->parent || !chip->to_irq)
345 return;
346
347 handle = ACPI_HANDLE(chip->parent);
348 if (!handle)
349 return;
350
351 status = acpi_get_data(handle, acpi_gpio_chip_dh, (void **)&acpi_gpio);
352 if (ACPI_FAILURE(status))
353 return;
354
355 list_for_each_entry_safe_reverse(event, ep, &acpi_gpio->events, node) {
356 struct gpio_desc *desc;
357
358 if (irqd_is_wakeup_set(irq_get_irq_data(event->irq)))
359 disable_irq_wake(event->irq);
360
361 free_irq(event->irq, event);
362 desc = event->desc;
363 if (WARN_ON(IS_ERR(desc)))
364 continue;
365 gpiochip_unlock_as_irq(chip, event->pin);
366 gpiochip_free_own_desc(desc);
367 list_del(&event->node);
368 kfree(event);
369 }
370 }
371 EXPORT_SYMBOL_GPL(acpi_gpiochip_free_interrupts);
372
373 int acpi_dev_add_driver_gpios(struct acpi_device *adev,
374 const struct acpi_gpio_mapping *gpios)
375 {
376 if (adev && gpios) {
377 adev->driver_gpios = gpios;
378 return 0;
379 }
380 return -EINVAL;
381 }
382 EXPORT_SYMBOL_GPL(acpi_dev_add_driver_gpios);
383
384 static void devm_acpi_dev_release_driver_gpios(struct device *dev, void *res)
385 {
386 acpi_dev_remove_driver_gpios(ACPI_COMPANION(dev));
387 }
388
389 int devm_acpi_dev_add_driver_gpios(struct device *dev,
390 const struct acpi_gpio_mapping *gpios)
391 {
392 void *res;
393 int ret;
394
395 res = devres_alloc(devm_acpi_dev_release_driver_gpios, 0, GFP_KERNEL);
396 if (!res)
397 return -ENOMEM;
398
399 ret = acpi_dev_add_driver_gpios(ACPI_COMPANION(dev), gpios);
400 if (ret) {
401 devres_free(res);
402 return ret;
403 }
404 devres_add(dev, res);
405 return 0;
406 }
407 EXPORT_SYMBOL_GPL(devm_acpi_dev_add_driver_gpios);
408
409 void devm_acpi_dev_remove_driver_gpios(struct device *dev)
410 {
411 WARN_ON(devres_release(dev, devm_acpi_dev_release_driver_gpios, NULL, NULL));
412 }
413 EXPORT_SYMBOL_GPL(devm_acpi_dev_remove_driver_gpios);
414
415 static bool acpi_get_driver_gpio_data(struct acpi_device *adev,
416 const char *name, int index,
417 struct acpi_reference_args *args)
418 {
419 const struct acpi_gpio_mapping *gm;
420
421 if (!adev->driver_gpios)
422 return false;
423
424 for (gm = adev->driver_gpios; gm->name; gm++)
425 if (!strcmp(name, gm->name) && gm->data && index < gm->size) {
426 const struct acpi_gpio_params *par = gm->data + index;
427
428 args->adev = adev;
429 args->args[0] = par->crs_entry_index;
430 args->args[1] = par->line_index;
431 args->args[2] = par->active_low;
432 args->nargs = 3;
433 return true;
434 }
435
436 return false;
437 }
438
439 static enum gpiod_flags
440 acpi_gpio_to_gpiod_flags(const struct acpi_resource_gpio *agpio)
441 {
442 bool pull_up = agpio->pin_config == ACPI_PIN_CONFIG_PULLUP;
443
444 switch (agpio->io_restriction) {
445 case ACPI_IO_RESTRICT_INPUT:
446 return GPIOD_IN;
447 case ACPI_IO_RESTRICT_OUTPUT:
448 /*
449 * ACPI GPIO resources don't contain an initial value for the
450 * GPIO. Therefore we deduce that value from the pull field
451 * instead. If the pin is pulled up we assume default to be
452 * high, otherwise low.
453 */
454 return pull_up ? GPIOD_OUT_HIGH : GPIOD_OUT_LOW;
455 default:
456 /*
457 * Assume that the BIOS has configured the direction and pull
458 * accordingly.
459 */
460 return GPIOD_ASIS;
461 }
462 }
463
464 int
465 acpi_gpio_update_gpiod_flags(enum gpiod_flags *flags, enum gpiod_flags update)
466 {
467 int ret = 0;
468
469 /*
470 * Check if the BIOS has IoRestriction with explicitly set direction
471 * and update @flags accordingly. Otherwise use whatever caller asked
472 * for.
473 */
474 if (update & GPIOD_FLAGS_BIT_DIR_SET) {
475 enum gpiod_flags diff = *flags ^ update;
476
477 /*
478 * Check if caller supplied incompatible GPIO initialization
479 * flags.
480 *
481 * Return %-EINVAL to notify that firmware has different
482 * settings and we are going to use them.
483 */
484 if (((*flags & GPIOD_FLAGS_BIT_DIR_SET) && (diff & GPIOD_FLAGS_BIT_DIR_OUT)) ||
485 ((*flags & GPIOD_FLAGS_BIT_DIR_OUT) && (diff & GPIOD_FLAGS_BIT_DIR_VAL)))
486 ret = -EINVAL;
487 *flags = update;
488 }
489 return ret;
490 }
491
492 struct acpi_gpio_lookup {
493 struct acpi_gpio_info info;
494 int index;
495 int pin_index;
496 bool active_low;
497 struct acpi_device *adev;
498 struct gpio_desc *desc;
499 int n;
500 };
501
502 static int acpi_populate_gpio_lookup(struct acpi_resource *ares, void *data)
503 {
504 struct acpi_gpio_lookup *lookup = data;
505
506 if (ares->type != ACPI_RESOURCE_TYPE_GPIO)
507 return 1;
508
509 if (lookup->n++ == lookup->index && !lookup->desc) {
510 const struct acpi_resource_gpio *agpio = &ares->data.gpio;
511 int pin_index = lookup->pin_index;
512
513 if (pin_index >= agpio->pin_table_length)
514 return 1;
515
516 lookup->desc = acpi_get_gpiod(agpio->resource_source.string_ptr,
517 agpio->pin_table[pin_index]);
518 lookup->info.gpioint =
519 agpio->connection_type == ACPI_RESOURCE_GPIO_TYPE_INT;
520
521 /*
522 * Polarity and triggering are only specified for GpioInt
523 * resource.
524 * Note: we expect here:
525 * - ACPI_ACTIVE_LOW == GPIO_ACTIVE_LOW
526 * - ACPI_ACTIVE_HIGH == GPIO_ACTIVE_HIGH
527 */
528 if (lookup->info.gpioint) {
529 lookup->info.flags = GPIOD_IN;
530 lookup->info.polarity = agpio->polarity;
531 lookup->info.triggering = agpio->triggering;
532 } else {
533 lookup->info.flags = acpi_gpio_to_gpiod_flags(agpio);
534 }
535
536 }
537
538 return 1;
539 }
540
541 static int acpi_gpio_resource_lookup(struct acpi_gpio_lookup *lookup,
542 struct acpi_gpio_info *info)
543 {
544 struct list_head res_list;
545 int ret;
546
547 INIT_LIST_HEAD(&res_list);
548
549 ret = acpi_dev_get_resources(lookup->adev, &res_list,
550 acpi_populate_gpio_lookup,
551 lookup);
552 if (ret < 0)
553 return ret;
554
555 acpi_dev_free_resource_list(&res_list);
556
557 if (!lookup->desc)
558 return -ENOENT;
559
560 if (info) {
561 *info = lookup->info;
562 if (lookup->active_low)
563 info->polarity = lookup->active_low;
564 }
565 return 0;
566 }
567
568 static int acpi_gpio_property_lookup(struct fwnode_handle *fwnode,
569 const char *propname, int index,
570 struct acpi_gpio_lookup *lookup)
571 {
572 struct acpi_reference_args args;
573 int ret;
574
575 memset(&args, 0, sizeof(args));
576 ret = __acpi_node_get_property_reference(fwnode, propname, index, 3,
577 &args);
578 if (ret) {
579 struct acpi_device *adev = to_acpi_device_node(fwnode);
580
581 if (!adev)
582 return ret;
583
584 if (!acpi_get_driver_gpio_data(adev, propname, index, &args))
585 return ret;
586 }
587 /*
588 * The property was found and resolved, so need to lookup the GPIO based
589 * on returned args.
590 */
591 lookup->adev = args.adev;
592 if (args.nargs != 3)
593 return -EPROTO;
594
595 lookup->index = args.args[0];
596 lookup->pin_index = args.args[1];
597 lookup->active_low = !!args.args[2];
598
599 return 0;
600 }
601
602 /**
603 * acpi_get_gpiod_by_index() - get a GPIO descriptor from device resources
604 * @adev: pointer to a ACPI device to get GPIO from
605 * @propname: Property name of the GPIO (optional)
606 * @index: index of GpioIo/GpioInt resource (starting from %0)
607 * @info: info pointer to fill in (optional)
608 *
609 * Function goes through ACPI resources for @adev and based on @index looks
610 * up a GpioIo/GpioInt resource, translates it to the Linux GPIO descriptor,
611 * and returns it. @index matches GpioIo/GpioInt resources only so if there
612 * are total %3 GPIO resources, the index goes from %0 to %2.
613 *
614 * If @propname is specified the GPIO is looked using device property. In
615 * that case @index is used to select the GPIO entry in the property value
616 * (in case of multiple).
617 *
618 * If the GPIO cannot be translated or there is an error an ERR_PTR is
619 * returned.
620 *
621 * Note: if the GPIO resource has multiple entries in the pin list, this
622 * function only returns the first.
623 */
624 static struct gpio_desc *acpi_get_gpiod_by_index(struct acpi_device *adev,
625 const char *propname, int index,
626 struct acpi_gpio_info *info)
627 {
628 struct acpi_gpio_lookup lookup;
629 int ret;
630
631 if (!adev)
632 return ERR_PTR(-ENODEV);
633
634 memset(&lookup, 0, sizeof(lookup));
635 lookup.index = index;
636
637 if (propname) {
638 dev_dbg(&adev->dev, "GPIO: looking up %s\n", propname);
639
640 ret = acpi_gpio_property_lookup(acpi_fwnode_handle(adev),
641 propname, index, &lookup);
642 if (ret)
643 return ERR_PTR(ret);
644
645 dev_dbg(&adev->dev, "GPIO: _DSD returned %s %d %d %u\n",
646 dev_name(&lookup.adev->dev), lookup.index,
647 lookup.pin_index, lookup.active_low);
648 } else {
649 dev_dbg(&adev->dev, "GPIO: looking up %d in _CRS\n", index);
650 lookup.adev = adev;
651 }
652
653 ret = acpi_gpio_resource_lookup(&lookup, info);
654 return ret ? ERR_PTR(ret) : lookup.desc;
655 }
656
657 struct gpio_desc *acpi_find_gpio(struct device *dev,
658 const char *con_id,
659 unsigned int idx,
660 enum gpiod_flags *dflags,
661 enum gpio_lookup_flags *lookupflags)
662 {
663 struct acpi_device *adev = ACPI_COMPANION(dev);
664 struct acpi_gpio_info info;
665 struct gpio_desc *desc;
666 char propname[32];
667 int err;
668 int i;
669
670 /* Try first from _DSD */
671 for (i = 0; i < ARRAY_SIZE(gpio_suffixes); i++) {
672 if (con_id) {
673 snprintf(propname, sizeof(propname), "%s-%s",
674 con_id, gpio_suffixes[i]);
675 } else {
676 snprintf(propname, sizeof(propname), "%s",
677 gpio_suffixes[i]);
678 }
679
680 desc = acpi_get_gpiod_by_index(adev, propname, idx, &info);
681 if (!IS_ERR(desc))
682 break;
683 if (PTR_ERR(desc) == -EPROBE_DEFER)
684 return ERR_CAST(desc);
685 }
686
687 /* Then from plain _CRS GPIOs */
688 if (IS_ERR(desc)) {
689 if (!acpi_can_fallback_to_crs(adev, con_id))
690 return ERR_PTR(-ENOENT);
691
692 desc = acpi_get_gpiod_by_index(adev, NULL, idx, &info);
693 if (IS_ERR(desc))
694 return desc;
695 }
696
697 if (info.gpioint &&
698 (*dflags == GPIOD_OUT_LOW || *dflags == GPIOD_OUT_HIGH)) {
699 dev_dbg(dev, "refusing GpioInt() entry when doing GPIOD_OUT_* lookup\n");
700 return ERR_PTR(-ENOENT);
701 }
702
703 if (info.polarity == GPIO_ACTIVE_LOW)
704 *lookupflags |= GPIO_ACTIVE_LOW;
705
706 err = acpi_gpio_update_gpiod_flags(dflags, info.flags);
707 if (err)
708 dev_dbg(dev, "Override GPIO initialization flags\n");
709
710 return desc;
711 }
712
713 /**
714 * acpi_node_get_gpiod() - get a GPIO descriptor from ACPI resources
715 * @fwnode: pointer to an ACPI firmware node to get the GPIO information from
716 * @propname: Property name of the GPIO
717 * @index: index of GpioIo/GpioInt resource (starting from %0)
718 * @info: info pointer to fill in (optional)
719 *
720 * If @fwnode is an ACPI device object, call %acpi_get_gpiod_by_index() for it.
721 * Otherwise (ie. it is a data-only non-device object), use the property-based
722 * GPIO lookup to get to the GPIO resource with the relevant information and use
723 * that to obtain the GPIO descriptor to return.
724 */
725 struct gpio_desc *acpi_node_get_gpiod(struct fwnode_handle *fwnode,
726 const char *propname, int index,
727 struct acpi_gpio_info *info)
728 {
729 struct acpi_gpio_lookup lookup;
730 struct acpi_device *adev;
731 int ret;
732
733 adev = to_acpi_device_node(fwnode);
734 if (adev)
735 return acpi_get_gpiod_by_index(adev, propname, index, info);
736
737 if (!is_acpi_data_node(fwnode))
738 return ERR_PTR(-ENODEV);
739
740 if (!propname)
741 return ERR_PTR(-EINVAL);
742
743 memset(&lookup, 0, sizeof(lookup));
744 lookup.index = index;
745
746 ret = acpi_gpio_property_lookup(fwnode, propname, index, &lookup);
747 if (ret)
748 return ERR_PTR(ret);
749
750 ret = acpi_gpio_resource_lookup(&lookup, info);
751 return ret ? ERR_PTR(ret) : lookup.desc;
752 }
753
754 /**
755 * acpi_dev_gpio_irq_get() - Find GpioInt and translate it to Linux IRQ number
756 * @adev: pointer to a ACPI device to get IRQ from
757 * @index: index of GpioInt resource (starting from %0)
758 *
759 * If the device has one or more GpioInt resources, this function can be
760 * used to translate from the GPIO offset in the resource to the Linux IRQ
761 * number.
762 *
763 * The function is idempotent, though each time it runs it will configure GPIO
764 * pin direction according to the flags in GpioInt resource.
765 *
766 * Return: Linux IRQ number (>%0) on success, negative errno on failure.
767 */
768 int acpi_dev_gpio_irq_get(struct acpi_device *adev, int index)
769 {
770 int idx, i;
771 unsigned int irq_flags;
772 int ret;
773
774 for (i = 0, idx = 0; idx <= index; i++) {
775 struct acpi_gpio_info info;
776 struct gpio_desc *desc;
777
778 desc = acpi_get_gpiod_by_index(adev, NULL, i, &info);
779
780 /* Ignore -EPROBE_DEFER, it only matters if idx matches */
781 if (IS_ERR(desc) && PTR_ERR(desc) != -EPROBE_DEFER)
782 return PTR_ERR(desc);
783
784 if (info.gpioint && idx++ == index) {
785 char label[32];
786 int irq;
787
788 if (IS_ERR(desc))
789 return PTR_ERR(desc);
790
791 irq = gpiod_to_irq(desc);
792 if (irq < 0)
793 return irq;
794
795 snprintf(label, sizeof(label), "GpioInt() %d", index);
796 ret = gpiod_configure_flags(desc, label, 0, info.flags);
797 if (ret < 0)
798 return ret;
799
800 irq_flags = acpi_dev_get_irq_type(info.triggering,
801 info.polarity);
802
803 /* Set type if specified and different than the current one */
804 if (irq_flags != IRQ_TYPE_NONE &&
805 irq_flags != irq_get_trigger_type(irq))
806 irq_set_irq_type(irq, irq_flags);
807
808 return irq;
809 }
810
811 }
812 return -ENOENT;
813 }
814 EXPORT_SYMBOL_GPL(acpi_dev_gpio_irq_get);
815
816 static acpi_status
817 acpi_gpio_adr_space_handler(u32 function, acpi_physical_address address,
818 u32 bits, u64 *value, void *handler_context,
819 void *region_context)
820 {
821 struct acpi_gpio_chip *achip = region_context;
822 struct gpio_chip *chip = achip->chip;
823 struct acpi_resource_gpio *agpio;
824 struct acpi_resource *ares;
825 int pin_index = (int)address;
826 acpi_status status;
827 int length;
828 int i;
829
830 status = acpi_buffer_to_resource(achip->conn_info.connection,
831 achip->conn_info.length, &ares);
832 if (ACPI_FAILURE(status))
833 return status;
834
835 if (WARN_ON(ares->type != ACPI_RESOURCE_TYPE_GPIO)) {
836 ACPI_FREE(ares);
837 return AE_BAD_PARAMETER;
838 }
839
840 agpio = &ares->data.gpio;
841
842 if (WARN_ON(agpio->io_restriction == ACPI_IO_RESTRICT_INPUT &&
843 function == ACPI_WRITE)) {
844 ACPI_FREE(ares);
845 return AE_BAD_PARAMETER;
846 }
847
848 length = min(agpio->pin_table_length, (u16)(pin_index + bits));
849 for (i = pin_index; i < length; ++i) {
850 int pin = agpio->pin_table[i];
851 struct acpi_gpio_connection *conn;
852 struct gpio_desc *desc;
853 bool found;
854
855 pin = acpi_gpiochip_pin_to_gpio_offset(chip->gpiodev, pin);
856 if (pin < 0) {
857 status = AE_BAD_PARAMETER;
858 goto out;
859 }
860
861 mutex_lock(&achip->conn_lock);
862
863 found = false;
864 list_for_each_entry(conn, &achip->conns, node) {
865 if (conn->pin == pin) {
866 found = true;
867 desc = conn->desc;
868 break;
869 }
870 }
871
872 /*
873 * The same GPIO can be shared between operation region and
874 * event but only if the access here is ACPI_READ. In that
875 * case we "borrow" the event GPIO instead.
876 */
877 if (!found && agpio->sharable == ACPI_SHARED &&
878 function == ACPI_READ) {
879 struct acpi_gpio_event *event;
880
881 list_for_each_entry(event, &achip->events, node) {
882 if (event->pin == pin) {
883 desc = event->desc;
884 found = true;
885 break;
886 }
887 }
888 }
889
890 if (!found) {
891 enum gpiod_flags flags = acpi_gpio_to_gpiod_flags(agpio);
892 const char *label = "ACPI:OpRegion";
893 int err;
894
895 desc = gpiochip_request_own_desc(chip, pin, label);
896 if (IS_ERR(desc)) {
897 status = AE_ERROR;
898 mutex_unlock(&achip->conn_lock);
899 goto out;
900 }
901
902 err = gpiod_configure_flags(desc, label, 0, flags);
903 if (err < 0) {
904 status = AE_NOT_CONFIGURED;
905 gpiochip_free_own_desc(desc);
906 mutex_unlock(&achip->conn_lock);
907 goto out;
908 }
909
910 conn = kzalloc(sizeof(*conn), GFP_KERNEL);
911 if (!conn) {
912 status = AE_NO_MEMORY;
913 gpiochip_free_own_desc(desc);
914 mutex_unlock(&achip->conn_lock);
915 goto out;
916 }
917
918 conn->pin = pin;
919 conn->desc = desc;
920 list_add_tail(&conn->node, &achip->conns);
921 }
922
923 mutex_unlock(&achip->conn_lock);
924
925 if (function == ACPI_WRITE)
926 gpiod_set_raw_value_cansleep(desc,
927 !!((1 << i) & *value));
928 else
929 *value |= (u64)gpiod_get_raw_value_cansleep(desc) << i;
930 }
931
932 out:
933 ACPI_FREE(ares);
934 return status;
935 }
936
937 static void acpi_gpiochip_request_regions(struct acpi_gpio_chip *achip)
938 {
939 struct gpio_chip *chip = achip->chip;
940 acpi_handle handle = ACPI_HANDLE(chip->parent);
941 acpi_status status;
942
943 INIT_LIST_HEAD(&achip->conns);
944 mutex_init(&achip->conn_lock);
945 status = acpi_install_address_space_handler(handle, ACPI_ADR_SPACE_GPIO,
946 acpi_gpio_adr_space_handler,
947 NULL, achip);
948 if (ACPI_FAILURE(status))
949 dev_err(chip->parent,
950 "Failed to install GPIO OpRegion handler\n");
951 }
952
953 static void acpi_gpiochip_free_regions(struct acpi_gpio_chip *achip)
954 {
955 struct gpio_chip *chip = achip->chip;
956 acpi_handle handle = ACPI_HANDLE(chip->parent);
957 struct acpi_gpio_connection *conn, *tmp;
958 acpi_status status;
959
960 status = acpi_remove_address_space_handler(handle, ACPI_ADR_SPACE_GPIO,
961 acpi_gpio_adr_space_handler);
962 if (ACPI_FAILURE(status)) {
963 dev_err(chip->parent,
964 "Failed to remove GPIO OpRegion handler\n");
965 return;
966 }
967
968 list_for_each_entry_safe_reverse(conn, tmp, &achip->conns, node) {
969 gpiochip_free_own_desc(conn->desc);
970 list_del(&conn->node);
971 kfree(conn);
972 }
973 }
974
975 static struct gpio_desc *acpi_gpiochip_parse_own_gpio(
976 struct acpi_gpio_chip *achip, struct fwnode_handle *fwnode,
977 const char **name, unsigned int *lflags, unsigned int *dflags)
978 {
979 struct gpio_chip *chip = achip->chip;
980 struct gpio_desc *desc;
981 u32 gpios[2];
982 int ret;
983
984 *lflags = 0;
985 *dflags = 0;
986 *name = NULL;
987
988 ret = fwnode_property_read_u32_array(fwnode, "gpios", gpios,
989 ARRAY_SIZE(gpios));
990 if (ret < 0)
991 return ERR_PTR(ret);
992
993 ret = acpi_gpiochip_pin_to_gpio_offset(chip->gpiodev, gpios[0]);
994 if (ret < 0)
995 return ERR_PTR(ret);
996
997 desc = gpiochip_get_desc(chip, ret);
998 if (IS_ERR(desc))
999 return desc;
1000
1001 if (gpios[1])
1002 *lflags |= GPIO_ACTIVE_LOW;
1003
1004 if (fwnode_property_present(fwnode, "input"))
1005 *dflags |= GPIOD_IN;
1006 else if (fwnode_property_present(fwnode, "output-low"))
1007 *dflags |= GPIOD_OUT_LOW;
1008 else if (fwnode_property_present(fwnode, "output-high"))
1009 *dflags |= GPIOD_OUT_HIGH;
1010 else
1011 return ERR_PTR(-EINVAL);
1012
1013 fwnode_property_read_string(fwnode, "line-name", name);
1014
1015 return desc;
1016 }
1017
1018 static void acpi_gpiochip_scan_gpios(struct acpi_gpio_chip *achip)
1019 {
1020 struct gpio_chip *chip = achip->chip;
1021 struct fwnode_handle *fwnode;
1022
1023 device_for_each_child_node(chip->parent, fwnode) {
1024 unsigned int lflags, dflags;
1025 struct gpio_desc *desc;
1026 const char *name;
1027 int ret;
1028
1029 if (!fwnode_property_present(fwnode, "gpio-hog"))
1030 continue;
1031
1032 desc = acpi_gpiochip_parse_own_gpio(achip, fwnode, &name,
1033 &lflags, &dflags);
1034 if (IS_ERR(desc))
1035 continue;
1036
1037 ret = gpiod_hog(desc, name, lflags, dflags);
1038 if (ret) {
1039 dev_err(chip->parent, "Failed to hog GPIO\n");
1040 fwnode_handle_put(fwnode);
1041 return;
1042 }
1043 }
1044 }
1045
1046 void acpi_gpiochip_add(struct gpio_chip *chip)
1047 {
1048 struct acpi_gpio_chip *acpi_gpio;
1049 acpi_handle handle;
1050 acpi_status status;
1051
1052 if (!chip || !chip->parent)
1053 return;
1054
1055 handle = ACPI_HANDLE(chip->parent);
1056 if (!handle)
1057 return;
1058
1059 acpi_gpio = kzalloc(sizeof(*acpi_gpio), GFP_KERNEL);
1060 if (!acpi_gpio) {
1061 dev_err(chip->parent,
1062 "Failed to allocate memory for ACPI GPIO chip\n");
1063 return;
1064 }
1065
1066 acpi_gpio->chip = chip;
1067 INIT_LIST_HEAD(&acpi_gpio->events);
1068
1069 status = acpi_attach_data(handle, acpi_gpio_chip_dh, acpi_gpio);
1070 if (ACPI_FAILURE(status)) {
1071 dev_err(chip->parent, "Failed to attach ACPI GPIO chip\n");
1072 kfree(acpi_gpio);
1073 return;
1074 }
1075
1076 if (!chip->names)
1077 devprop_gpiochip_set_names(chip);
1078
1079 acpi_gpiochip_request_regions(acpi_gpio);
1080 acpi_gpiochip_scan_gpios(acpi_gpio);
1081 acpi_walk_dep_device_list(handle);
1082 }
1083
1084 void acpi_gpiochip_remove(struct gpio_chip *chip)
1085 {
1086 struct acpi_gpio_chip *acpi_gpio;
1087 acpi_handle handle;
1088 acpi_status status;
1089
1090 if (!chip || !chip->parent)
1091 return;
1092
1093 handle = ACPI_HANDLE(chip->parent);
1094 if (!handle)
1095 return;
1096
1097 status = acpi_get_data(handle, acpi_gpio_chip_dh, (void **)&acpi_gpio);
1098 if (ACPI_FAILURE(status)) {
1099 dev_warn(chip->parent, "Failed to retrieve ACPI GPIO chip\n");
1100 return;
1101 }
1102
1103 acpi_gpiochip_free_regions(acpi_gpio);
1104
1105 acpi_detach_data(handle, acpi_gpio_chip_dh);
1106 kfree(acpi_gpio);
1107 }
1108
1109 static int acpi_gpio_package_count(const union acpi_object *obj)
1110 {
1111 const union acpi_object *element = obj->package.elements;
1112 const union acpi_object *end = element + obj->package.count;
1113 unsigned int count = 0;
1114
1115 while (element < end) {
1116 switch (element->type) {
1117 case ACPI_TYPE_LOCAL_REFERENCE:
1118 element += 3;
1119 /* Fallthrough */
1120 case ACPI_TYPE_INTEGER:
1121 element++;
1122 count++;
1123 break;
1124
1125 default:
1126 return -EPROTO;
1127 }
1128 }
1129
1130 return count;
1131 }
1132
1133 static int acpi_find_gpio_count(struct acpi_resource *ares, void *data)
1134 {
1135 unsigned int *count = data;
1136
1137 if (ares->type == ACPI_RESOURCE_TYPE_GPIO)
1138 *count += ares->data.gpio.pin_table_length;
1139
1140 return 1;
1141 }
1142
1143 /**
1144 * acpi_gpio_count - return the number of GPIOs associated with a
1145 * device / function or -ENOENT if no GPIO has been
1146 * assigned to the requested function.
1147 * @dev: GPIO consumer, can be NULL for system-global GPIOs
1148 * @con_id: function within the GPIO consumer
1149 */
1150 int acpi_gpio_count(struct device *dev, const char *con_id)
1151 {
1152 struct acpi_device *adev = ACPI_COMPANION(dev);
1153 const union acpi_object *obj;
1154 const struct acpi_gpio_mapping *gm;
1155 int count = -ENOENT;
1156 int ret;
1157 char propname[32];
1158 unsigned int i;
1159
1160 /* Try first from _DSD */
1161 for (i = 0; i < ARRAY_SIZE(gpio_suffixes); i++) {
1162 if (con_id)
1163 snprintf(propname, sizeof(propname), "%s-%s",
1164 con_id, gpio_suffixes[i]);
1165 else
1166 snprintf(propname, sizeof(propname), "%s",
1167 gpio_suffixes[i]);
1168
1169 ret = acpi_dev_get_property(adev, propname, ACPI_TYPE_ANY,
1170 &obj);
1171 if (ret == 0) {
1172 if (obj->type == ACPI_TYPE_LOCAL_REFERENCE)
1173 count = 1;
1174 else if (obj->type == ACPI_TYPE_PACKAGE)
1175 count = acpi_gpio_package_count(obj);
1176 } else if (adev->driver_gpios) {
1177 for (gm = adev->driver_gpios; gm->name; gm++)
1178 if (strcmp(propname, gm->name) == 0) {
1179 count = gm->size;
1180 break;
1181 }
1182 }
1183 if (count > 0)
1184 break;
1185 }
1186
1187 /* Then from plain _CRS GPIOs */
1188 if (count < 0) {
1189 struct list_head resource_list;
1190 unsigned int crs_count = 0;
1191
1192 if (!acpi_can_fallback_to_crs(adev, con_id))
1193 return count;
1194
1195 INIT_LIST_HEAD(&resource_list);
1196 acpi_dev_get_resources(adev, &resource_list,
1197 acpi_find_gpio_count, &crs_count);
1198 acpi_dev_free_resource_list(&resource_list);
1199 if (crs_count > 0)
1200 count = crs_count;
1201 }
1202 return count ? count : -ENOENT;
1203 }
1204
1205 bool acpi_can_fallback_to_crs(struct acpi_device *adev, const char *con_id)
1206 {
1207 /* Never allow fallback if the device has properties */
1208 if (adev->data.properties || adev->driver_gpios)
1209 return false;
1210
1211 return con_id == NULL;
1212 }
Linux with added FPC-III support