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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/dmi.h>
11#include <linux/errno.h>
12#include <linux/gpio/consumer.h>
13#include <linux/gpio/driver.h>
14#include <linux/gpio/machine.h>
15#include <linux/export.h>
16#include <linux/acpi.h>
17#include <linux/interrupt.h>
18#include <linux/mutex.h>
19#include <linux/pinctrl/pinctrl.h>
20
21#include "gpiolib.h"
22#include "gpiolib-acpi.h"
23
24static int run_edge_events_on_boot = -1;
25module_param(run_edge_events_on_boot, int, 0444);
26MODULE_PARM_DESC(run_edge_events_on_boot,
27 "Run edge _AEI event-handlers at boot: 0=no, 1=yes, -1=auto");
28
29/**
30 * struct acpi_gpio_event - ACPI GPIO event handler data
31 *
32 * @node: list-entry of the events list of the struct acpi_gpio_chip
33 * @handle: handle of ACPI method to execute when the IRQ triggers
34 * @handler: handler function to pass to request_irq() when requesting the IRQ
35 * @pin: GPIO pin number on the struct gpio_chip
36 * @irq: Linux IRQ number for the event, for request_irq() / free_irq()
37 * @irqflags: flags to pass to request_irq() when requesting the IRQ
38 * @irq_is_wake: If the ACPI flags indicate the IRQ is a wakeup source
39 * @irq_requested:True if request_irq() has been done
40 * @desc: struct gpio_desc for the GPIO pin for this event
41 */
42struct acpi_gpio_event {
43 struct list_head node;
44 acpi_handle handle;
45 irq_handler_t handler;
46 unsigned int pin;
47 unsigned int irq;
48 unsigned long irqflags;
49 bool irq_is_wake;
50 bool irq_requested;
51 struct gpio_desc *desc;
52};
53
54struct acpi_gpio_connection {
55 struct list_head node;
56 unsigned int pin;
57 struct gpio_desc *desc;
58};
59
60struct acpi_gpio_chip {
61 /*
62 * ACPICA requires that the first field of the context parameter
63 * passed to acpi_install_address_space_handler() is large enough
64 * to hold struct acpi_connection_info.
65 */
66 struct acpi_connection_info conn_info;
67 struct list_head conns;
68 struct mutex conn_lock;
69 struct gpio_chip *chip;
70 struct list_head events;
71 struct list_head deferred_req_irqs_list_entry;
72};
73
74/*
75 * For GPIO chips which call acpi_gpiochip_request_interrupts() before late_init
76 * (so builtin drivers) we register the ACPI GpioInt IRQ handlers from a
77 * late_initcall_sync() handler, so that other builtin drivers can register their
78 * OpRegions before the event handlers can run. This list contains GPIO chips
79 * for which the acpi_gpiochip_request_irqs() call has been deferred.
80 */
81static DEFINE_MUTEX(acpi_gpio_deferred_req_irqs_lock);
82static LIST_HEAD(acpi_gpio_deferred_req_irqs_list);
83static bool acpi_gpio_deferred_req_irqs_done;
84
85static int acpi_gpiochip_find(struct gpio_chip *gc, void *data)
86{
87 if (!gc->parent)
88 return false;
89
90 return ACPI_HANDLE(gc->parent) == data;
91}
92
93/**
94 * acpi_get_gpiod() - Translate ACPI GPIO pin to GPIO descriptor usable with GPIO API
95 * @path: ACPI GPIO controller full path name, (e.g. "\\_SB.GPO1")
96 * @pin: ACPI GPIO pin number (0-based, controller-relative)
97 *
98 * Return: GPIO descriptor to use with Linux generic GPIO API, or ERR_PTR
99 * error value. Specifically returns %-EPROBE_DEFER if the referenced GPIO
100 * controller does not have GPIO chip registered at the moment. This is to
101 * support probe deferral.
102 */
103static struct gpio_desc *acpi_get_gpiod(char *path, int pin)
104{
105 struct gpio_chip *chip;
106 acpi_handle handle;
107 acpi_status status;
108
109 status = acpi_get_handle(NULL, path, &handle);
110 if (ACPI_FAILURE(status))
111 return ERR_PTR(-ENODEV);
112
113 chip = gpiochip_find(handle, acpi_gpiochip_find);
114 if (!chip)
115 return ERR_PTR(-EPROBE_DEFER);
116
117 return gpiochip_get_desc(chip, pin);
118}
119
120static irqreturn_t acpi_gpio_irq_handler(int irq, void *data)
121{
122 struct acpi_gpio_event *event = data;
123
124 acpi_evaluate_object(event->handle, NULL, NULL, NULL);
125
126 return IRQ_HANDLED;
127}
128
129static irqreturn_t acpi_gpio_irq_handler_evt(int irq, void *data)
130{
131 struct acpi_gpio_event *event = data;
132
133 acpi_execute_simple_method(event->handle, NULL, event->pin);
134
135 return IRQ_HANDLED;
136}
137
138static void acpi_gpio_chip_dh(acpi_handle handle, void *data)
139{
140 /* The address of this function is used as a key. */
141}
142
143bool acpi_gpio_get_irq_resource(struct acpi_resource *ares,
144 struct acpi_resource_gpio **agpio)
145{
146 struct acpi_resource_gpio *gpio;
147
148 if (ares->type != ACPI_RESOURCE_TYPE_GPIO)
149 return false;
150
151 gpio = &ares->data.gpio;
152 if (gpio->connection_type != ACPI_RESOURCE_GPIO_TYPE_INT)
153 return false;
154
155 *agpio = gpio;
156 return true;
157}
158EXPORT_SYMBOL_GPL(acpi_gpio_get_irq_resource);
159
160static void acpi_gpiochip_request_irq(struct acpi_gpio_chip *acpi_gpio,
161 struct acpi_gpio_event *event)
162{
163 int ret, value;
164
165 ret = request_threaded_irq(event->irq, NULL, event->handler,
166 event->irqflags, "ACPI:Event", event);
167 if (ret) {
168 dev_err(acpi_gpio->chip->parent,
169 "Failed to setup interrupt handler for %d\n",
170 event->irq);
171 return;
172 }
173
174 if (event->irq_is_wake)
175 enable_irq_wake(event->irq);
176
177 event->irq_requested = true;
178
179 /* Make sure we trigger the initial state of edge-triggered IRQs */
180 if (run_edge_events_on_boot &&
181 (event->irqflags & (IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING))) {
182 value = gpiod_get_raw_value_cansleep(event->desc);
183 if (((event->irqflags & IRQF_TRIGGER_RISING) && value == 1) ||
184 ((event->irqflags & IRQF_TRIGGER_FALLING) && value == 0))
185 event->handler(event->irq, event);
186 }
187}
188
189static void acpi_gpiochip_request_irqs(struct acpi_gpio_chip *acpi_gpio)
190{
191 struct acpi_gpio_event *event;
192
193 list_for_each_entry(event, &acpi_gpio->events, node)
194 acpi_gpiochip_request_irq(acpi_gpio, event);
195}
196
197static acpi_status acpi_gpiochip_alloc_event(struct acpi_resource *ares,
198 void *context)
199{
200 struct acpi_gpio_chip *acpi_gpio = context;
201 struct gpio_chip *chip = acpi_gpio->chip;
202 struct acpi_resource_gpio *agpio;
203 acpi_handle handle, evt_handle;
204 struct acpi_gpio_event *event;
205 irq_handler_t handler = NULL;
206 struct gpio_desc *desc;
207 int ret, pin, irq;
208
209 if (!acpi_gpio_get_irq_resource(ares, &agpio))
210 return AE_OK;
211
212 handle = ACPI_HANDLE(chip->parent);
213 pin = agpio->pin_table[0];
214
215 if (pin <= 255) {
216 char ev_name[5];
217 sprintf(ev_name, "_%c%02hhX",
218 agpio->triggering == ACPI_EDGE_SENSITIVE ? 'E' : 'L',
219 pin);
220 if (ACPI_SUCCESS(acpi_get_handle(handle, ev_name, &evt_handle)))
221 handler = acpi_gpio_irq_handler;
222 }
223 if (!handler) {
224 if (ACPI_SUCCESS(acpi_get_handle(handle, "_EVT", &evt_handle)))
225 handler = acpi_gpio_irq_handler_evt;
226 }
227 if (!handler)
228 return AE_OK;
229
230 desc = gpiochip_request_own_desc(chip, pin, "ACPI:Event",
231 GPIO_ACTIVE_HIGH, GPIOD_IN);
232 if (IS_ERR(desc)) {
233 dev_err(chip->parent, "Failed to request GPIO\n");
234 return AE_ERROR;
235 }
236
237 ret = gpiochip_lock_as_irq(chip, pin);
238 if (ret) {
239 dev_err(chip->parent, "Failed to lock GPIO as interrupt\n");
240 goto fail_free_desc;
241 }
242
243 irq = gpiod_to_irq(desc);
244 if (irq < 0) {
245 dev_err(chip->parent, "Failed to translate GPIO to IRQ\n");
246 goto fail_unlock_irq;
247 }
248
249 event = kzalloc(sizeof(*event), GFP_KERNEL);
250 if (!event)
251 goto fail_unlock_irq;
252
253 event->irqflags = IRQF_ONESHOT;
254 if (agpio->triggering == ACPI_LEVEL_SENSITIVE) {
255 if (agpio->polarity == ACPI_ACTIVE_HIGH)
256 event->irqflags |= IRQF_TRIGGER_HIGH;
257 else
258 event->irqflags |= IRQF_TRIGGER_LOW;
259 } else {
260 switch (agpio->polarity) {
261 case ACPI_ACTIVE_HIGH:
262 event->irqflags |= IRQF_TRIGGER_RISING;
263 break;
264 case ACPI_ACTIVE_LOW:
265 event->irqflags |= IRQF_TRIGGER_FALLING;
266 break;
267 default:
268 event->irqflags |= IRQF_TRIGGER_RISING |
269 IRQF_TRIGGER_FALLING;
270 break;
271 }
272 }
273
274 event->handle = evt_handle;
275 event->handler = handler;
276 event->irq = irq;
277 event->irq_is_wake = agpio->wake_capable == ACPI_WAKE_CAPABLE;
278 event->pin = pin;
279 event->desc = desc;
280
281 list_add_tail(&event->node, &acpi_gpio->events);
282
283 return AE_OK;
284
285fail_unlock_irq:
286 gpiochip_unlock_as_irq(chip, pin);
287fail_free_desc:
288 gpiochip_free_own_desc(desc);
289
290 return AE_ERROR;
291}
292
293/**
294 * acpi_gpiochip_request_interrupts() - Register isr for gpio chip ACPI events
295 * @chip: GPIO chip
296 *
297 * ACPI5 platforms can use GPIO signaled ACPI events. These GPIO interrupts are
298 * handled by ACPI event methods which need to be called from the GPIO
299 * chip's interrupt handler. acpi_gpiochip_request_interrupts() finds out which
300 * GPIO pins have ACPI event methods and assigns interrupt handlers that calls
301 * the ACPI event methods for those pins.
302 */
303void acpi_gpiochip_request_interrupts(struct gpio_chip *chip)
304{
305 struct acpi_gpio_chip *acpi_gpio;
306 acpi_handle handle;
307 acpi_status status;
308 bool defer;
309
310 if (!chip->parent || !chip->to_irq)
311 return;
312
313 handle = ACPI_HANDLE(chip->parent);
314 if (!handle)
315 return;
316
317 status = acpi_get_data(handle, acpi_gpio_chip_dh, (void **)&acpi_gpio);
318 if (ACPI_FAILURE(status))
319 return;
320
321 acpi_walk_resources(handle, "_AEI",
322 acpi_gpiochip_alloc_event, acpi_gpio);
323
324 mutex_lock(&acpi_gpio_deferred_req_irqs_lock);
325 defer = !acpi_gpio_deferred_req_irqs_done;
326 if (defer)
327 list_add(&acpi_gpio->deferred_req_irqs_list_entry,
328 &acpi_gpio_deferred_req_irqs_list);
329 mutex_unlock(&acpi_gpio_deferred_req_irqs_lock);
330
331 if (defer)
332 return;
333
334 acpi_gpiochip_request_irqs(acpi_gpio);
335}
336EXPORT_SYMBOL_GPL(acpi_gpiochip_request_interrupts);
337
338/**
339 * acpi_gpiochip_free_interrupts() - Free GPIO ACPI event interrupts.
340 * @chip: GPIO chip
341 *
342 * Free interrupts associated with GPIO ACPI event method for the given
343 * GPIO chip.
344 */
345void acpi_gpiochip_free_interrupts(struct gpio_chip *chip)
346{
347 struct acpi_gpio_chip *acpi_gpio;
348 struct acpi_gpio_event *event, *ep;
349 acpi_handle handle;
350 acpi_status status;
351
352 if (!chip->parent || !chip->to_irq)
353 return;
354
355 handle = ACPI_HANDLE(chip->parent);
356 if (!handle)
357 return;
358
359 status = acpi_get_data(handle, acpi_gpio_chip_dh, (void **)&acpi_gpio);
360 if (ACPI_FAILURE(status))
361 return;
362
363 mutex_lock(&acpi_gpio_deferred_req_irqs_lock);
364 if (!list_empty(&acpi_gpio->deferred_req_irqs_list_entry))
365 list_del_init(&acpi_gpio->deferred_req_irqs_list_entry);
366 mutex_unlock(&acpi_gpio_deferred_req_irqs_lock);
367
368 list_for_each_entry_safe_reverse(event, ep, &acpi_gpio->events, node) {
369 if (event->irq_requested) {
370 if (event->irq_is_wake)
371 disable_irq_wake(event->irq);
372
373 free_irq(event->irq, event);
374 }
375
376 gpiochip_unlock_as_irq(chip, event->pin);
377 gpiochip_free_own_desc(event->desc);
378 list_del(&event->node);
379 kfree(event);
380 }
381}
382EXPORT_SYMBOL_GPL(acpi_gpiochip_free_interrupts);
383
384int acpi_dev_add_driver_gpios(struct acpi_device *adev,
385 const struct acpi_gpio_mapping *gpios)
386{
387 if (adev && gpios) {
388 adev->driver_gpios = gpios;
389 return 0;
390 }
391 return -EINVAL;
392}
393EXPORT_SYMBOL_GPL(acpi_dev_add_driver_gpios);
394
395void acpi_dev_remove_driver_gpios(struct acpi_device *adev)
396{
397 if (adev)
398 adev->driver_gpios = NULL;
399}
400EXPORT_SYMBOL_GPL(acpi_dev_remove_driver_gpios);
401
402static void devm_acpi_dev_release_driver_gpios(struct device *dev, void *res)
403{
404 acpi_dev_remove_driver_gpios(ACPI_COMPANION(dev));
405}
406
407int devm_acpi_dev_add_driver_gpios(struct device *dev,
408 const struct acpi_gpio_mapping *gpios)
409{
410 void *res;
411 int ret;
412
413 res = devres_alloc(devm_acpi_dev_release_driver_gpios, 0, GFP_KERNEL);
414 if (!res)
415 return -ENOMEM;
416
417 ret = acpi_dev_add_driver_gpios(ACPI_COMPANION(dev), gpios);
418 if (ret) {
419 devres_free(res);
420 return ret;
421 }
422 devres_add(dev, res);
423 return 0;
424}
425EXPORT_SYMBOL_GPL(devm_acpi_dev_add_driver_gpios);
426
427void devm_acpi_dev_remove_driver_gpios(struct device *dev)
428{
429 WARN_ON(devres_release(dev, devm_acpi_dev_release_driver_gpios, NULL, NULL));
430}
431EXPORT_SYMBOL_GPL(devm_acpi_dev_remove_driver_gpios);
432
433static bool acpi_get_driver_gpio_data(struct acpi_device *adev,
434 const char *name, int index,
435 struct fwnode_reference_args *args,
436 unsigned int *quirks)
437{
438 const struct acpi_gpio_mapping *gm;
439
440 if (!adev->driver_gpios)
441 return false;
442
443 for (gm = adev->driver_gpios; gm->name; gm++)
444 if (!strcmp(name, gm->name) && gm->data && index < gm->size) {
445 const struct acpi_gpio_params *par = gm->data + index;
446
447 args->fwnode = acpi_fwnode_handle(adev);
448 args->args[0] = par->crs_entry_index;
449 args->args[1] = par->line_index;
450 args->args[2] = par->active_low;
451 args->nargs = 3;
452
453 *quirks = gm->quirks;
454 return true;
455 }
456
457 return false;
458}
459
460static enum gpiod_flags
461acpi_gpio_to_gpiod_flags(const struct acpi_resource_gpio *agpio)
462{
463 switch (agpio->io_restriction) {
464 case ACPI_IO_RESTRICT_INPUT:
465 return GPIOD_IN;
466 case ACPI_IO_RESTRICT_OUTPUT:
467 /*
468 * ACPI GPIO resources don't contain an initial value for the
469 * GPIO. Therefore we deduce that value from the pull field
470 * instead. If the pin is pulled up we assume default to be
471 * high, if it is pulled down we assume default to be low,
472 * otherwise we leave pin untouched.
473 */
474 switch (agpio->pin_config) {
475 case ACPI_PIN_CONFIG_PULLUP:
476 return GPIOD_OUT_HIGH;
477 case ACPI_PIN_CONFIG_PULLDOWN:
478 return GPIOD_OUT_LOW;
479 default:
480 break;
481 }
482 default:
483 break;
484 }
485
486 /*
487 * Assume that the BIOS has configured the direction and pull
488 * accordingly.
489 */
490 return GPIOD_ASIS;
491}
492
493static int
494__acpi_gpio_update_gpiod_flags(enum gpiod_flags *flags, enum gpiod_flags update)
495{
496 const enum gpiod_flags mask =
497 GPIOD_FLAGS_BIT_DIR_SET | GPIOD_FLAGS_BIT_DIR_OUT |
498 GPIOD_FLAGS_BIT_DIR_VAL;
499 int ret = 0;
500
501 /*
502 * Check if the BIOS has IoRestriction with explicitly set direction
503 * and update @flags accordingly. Otherwise use whatever caller asked
504 * for.
505 */
506 if (update & GPIOD_FLAGS_BIT_DIR_SET) {
507 enum gpiod_flags diff = *flags ^ update;
508
509 /*
510 * Check if caller supplied incompatible GPIO initialization
511 * flags.
512 *
513 * Return %-EINVAL to notify that firmware has different
514 * settings and we are going to use them.
515 */
516 if (((*flags & GPIOD_FLAGS_BIT_DIR_SET) && (diff & GPIOD_FLAGS_BIT_DIR_OUT)) ||
517 ((*flags & GPIOD_FLAGS_BIT_DIR_OUT) && (diff & GPIOD_FLAGS_BIT_DIR_VAL)))
518 ret = -EINVAL;
519 *flags = (*flags & ~mask) | (update & mask);
520 }
521 return ret;
522}
523
524int
525acpi_gpio_update_gpiod_flags(enum gpiod_flags *flags, struct acpi_gpio_info *info)
526{
527 struct device *dev = &info->adev->dev;
528 enum gpiod_flags old = *flags;
529 int ret;
530
531 ret = __acpi_gpio_update_gpiod_flags(&old, info->flags);
532 if (info->quirks & ACPI_GPIO_QUIRK_NO_IO_RESTRICTION) {
533 if (ret)
534 dev_warn(dev, FW_BUG "GPIO not in correct mode, fixing\n");
535 } else {
536 if (ret)
537 dev_dbg(dev, "Override GPIO initialization flags\n");
538 *flags = old;
539 }
540
541 return ret;
542}
543
544int acpi_gpio_update_gpiod_lookup_flags(unsigned long *lookupflags,
545 struct acpi_gpio_info *info)
546{
547 switch (info->pin_config) {
548 case ACPI_PIN_CONFIG_PULLUP:
549 *lookupflags |= GPIO_PULL_UP;
550 break;
551 case ACPI_PIN_CONFIG_PULLDOWN:
552 *lookupflags |= GPIO_PULL_DOWN;
553 break;
554 default:
555 break;
556 }
557
558 if (info->polarity == GPIO_ACTIVE_LOW)
559 *lookupflags |= GPIO_ACTIVE_LOW;
560
561 return 0;
562}
563
564struct acpi_gpio_lookup {
565 struct acpi_gpio_info info;
566 int index;
567 int pin_index;
568 bool active_low;
569 struct gpio_desc *desc;
570 int n;
571};
572
573static int acpi_populate_gpio_lookup(struct acpi_resource *ares, void *data)
574{
575 struct acpi_gpio_lookup *lookup = data;
576
577 if (ares->type != ACPI_RESOURCE_TYPE_GPIO)
578 return 1;
579
580 if (!lookup->desc) {
581 const struct acpi_resource_gpio *agpio = &ares->data.gpio;
582 bool gpioint = agpio->connection_type == ACPI_RESOURCE_GPIO_TYPE_INT;
583 int pin_index;
584
585 if (lookup->info.quirks & ACPI_GPIO_QUIRK_ONLY_GPIOIO && gpioint)
586 lookup->index++;
587
588 if (lookup->n++ != lookup->index)
589 return 1;
590
591 pin_index = lookup->pin_index;
592 if (pin_index >= agpio->pin_table_length)
593 return 1;
594
595 lookup->desc = acpi_get_gpiod(agpio->resource_source.string_ptr,
596 agpio->pin_table[pin_index]);
597 lookup->info.pin_config = agpio->pin_config;
598 lookup->info.gpioint = gpioint;
599
600 /*
601 * Polarity and triggering are only specified for GpioInt
602 * resource.
603 * Note: we expect here:
604 * - ACPI_ACTIVE_LOW == GPIO_ACTIVE_LOW
605 * - ACPI_ACTIVE_HIGH == GPIO_ACTIVE_HIGH
606 */
607 if (lookup->info.gpioint) {
608 lookup->info.flags = GPIOD_IN;
609 lookup->info.polarity = agpio->polarity;
610 lookup->info.triggering = agpio->triggering;
611 } else {
612 lookup->info.flags = acpi_gpio_to_gpiod_flags(agpio);
613 lookup->info.polarity = lookup->active_low;
614 }
615 }
616
617 return 1;
618}
619
620static int acpi_gpio_resource_lookup(struct acpi_gpio_lookup *lookup,
621 struct acpi_gpio_info *info)
622{
623 struct acpi_device *adev = lookup->info.adev;
624 struct list_head res_list;
625 int ret;
626
627 INIT_LIST_HEAD(&res_list);
628
629 ret = acpi_dev_get_resources(adev, &res_list,
630 acpi_populate_gpio_lookup,
631 lookup);
632 if (ret < 0)
633 return ret;
634
635 acpi_dev_free_resource_list(&res_list);
636
637 if (!lookup->desc)
638 return -ENOENT;
639
640 if (info)
641 *info = lookup->info;
642 return 0;
643}
644
645static int acpi_gpio_property_lookup(struct fwnode_handle *fwnode,
646 const char *propname, int index,
647 struct acpi_gpio_lookup *lookup)
648{
649 struct fwnode_reference_args args;
650 unsigned int quirks = 0;
651 int ret;
652
653 memset(&args, 0, sizeof(args));
654 ret = __acpi_node_get_property_reference(fwnode, propname, index, 3,
655 &args);
656 if (ret) {
657 struct acpi_device *adev = to_acpi_device_node(fwnode);
658
659 if (!adev)
660 return ret;
661
662 if (!acpi_get_driver_gpio_data(adev, propname, index, &args,
663 &quirks))
664 return ret;
665 }
666 /*
667 * The property was found and resolved, so need to lookup the GPIO based
668 * on returned args.
669 */
670 if (!to_acpi_device_node(args.fwnode))
671 return -EINVAL;
672 if (args.nargs != 3)
673 return -EPROTO;
674
675 lookup->index = args.args[0];
676 lookup->pin_index = args.args[1];
677 lookup->active_low = !!args.args[2];
678
679 lookup->info.adev = to_acpi_device_node(args.fwnode);
680 lookup->info.quirks = quirks;
681
682 return 0;
683}
684
685/**
686 * acpi_get_gpiod_by_index() - get a GPIO descriptor from device resources
687 * @adev: pointer to a ACPI device to get GPIO from
688 * @propname: Property name of the GPIO (optional)
689 * @index: index of GpioIo/GpioInt resource (starting from %0)
690 * @info: info pointer to fill in (optional)
691 *
692 * Function goes through ACPI resources for @adev and based on @index looks
693 * up a GpioIo/GpioInt resource, translates it to the Linux GPIO descriptor,
694 * and returns it. @index matches GpioIo/GpioInt resources only so if there
695 * are total %3 GPIO resources, the index goes from %0 to %2.
696 *
697 * If @propname is specified the GPIO is looked using device property. In
698 * that case @index is used to select the GPIO entry in the property value
699 * (in case of multiple).
700 *
701 * If the GPIO cannot be translated or there is an error, an ERR_PTR is
702 * returned.
703 *
704 * Note: if the GPIO resource has multiple entries in the pin list, this
705 * function only returns the first.
706 */
707static struct gpio_desc *acpi_get_gpiod_by_index(struct acpi_device *adev,
708 const char *propname, int index,
709 struct acpi_gpio_info *info)
710{
711 struct acpi_gpio_lookup lookup;
712 int ret;
713
714 if (!adev)
715 return ERR_PTR(-ENODEV);
716
717 memset(&lookup, 0, sizeof(lookup));
718 lookup.index = index;
719
720 if (propname) {
721 dev_dbg(&adev->dev, "GPIO: looking up %s\n", propname);
722
723 ret = acpi_gpio_property_lookup(acpi_fwnode_handle(adev),
724 propname, index, &lookup);
725 if (ret)
726 return ERR_PTR(ret);
727
728 dev_dbg(&adev->dev, "GPIO: _DSD returned %s %d %d %u\n",
729 dev_name(&lookup.info.adev->dev), lookup.index,
730 lookup.pin_index, lookup.active_low);
731 } else {
732 dev_dbg(&adev->dev, "GPIO: looking up %d in _CRS\n", index);
733 lookup.info.adev = adev;
734 }
735
736 ret = acpi_gpio_resource_lookup(&lookup, info);
737 return ret ? ERR_PTR(ret) : lookup.desc;
738}
739
740static bool acpi_can_fallback_to_crs(struct acpi_device *adev,
741 const char *con_id)
742{
743 /* Never allow fallback if the device has properties */
744 if (acpi_dev_has_props(adev) || adev->driver_gpios)
745 return false;
746
747 return con_id == NULL;
748}
749
750struct gpio_desc *acpi_find_gpio(struct device *dev,
751 const char *con_id,
752 unsigned int idx,
753 enum gpiod_flags *dflags,
754 unsigned long *lookupflags)
755{
756 struct acpi_device *adev = ACPI_COMPANION(dev);
757 struct acpi_gpio_info info;
758 struct gpio_desc *desc;
759 char propname[32];
760 int i;
761
762 /* Try first from _DSD */
763 for (i = 0; i < ARRAY_SIZE(gpio_suffixes); i++) {
764 if (con_id) {
765 snprintf(propname, sizeof(propname), "%s-%s",
766 con_id, gpio_suffixes[i]);
767 } else {
768 snprintf(propname, sizeof(propname), "%s",
769 gpio_suffixes[i]);
770 }
771
772 desc = acpi_get_gpiod_by_index(adev, propname, idx, &info);
773 if (!IS_ERR(desc))
774 break;
775 if (PTR_ERR(desc) == -EPROBE_DEFER)
776 return ERR_CAST(desc);
777 }
778
779 /* Then from plain _CRS GPIOs */
780 if (IS_ERR(desc)) {
781 if (!acpi_can_fallback_to_crs(adev, con_id))
782 return ERR_PTR(-ENOENT);
783
784 desc = acpi_get_gpiod_by_index(adev, NULL, idx, &info);
785 if (IS_ERR(desc))
786 return desc;
787 }
788
789 if (info.gpioint &&
790 (*dflags == GPIOD_OUT_LOW || *dflags == GPIOD_OUT_HIGH)) {
791 dev_dbg(dev, "refusing GpioInt() entry when doing GPIOD_OUT_* lookup\n");
792 return ERR_PTR(-ENOENT);
793 }
794
795 acpi_gpio_update_gpiod_flags(dflags, &info);
796 acpi_gpio_update_gpiod_lookup_flags(lookupflags, &info);
797 return desc;
798}
799
800/**
801 * acpi_node_get_gpiod() - get a GPIO descriptor from ACPI resources
802 * @fwnode: pointer to an ACPI firmware node to get the GPIO information from
803 * @propname: Property name of the GPIO
804 * @index: index of GpioIo/GpioInt resource (starting from %0)
805 * @info: info pointer to fill in (optional)
806 *
807 * If @fwnode is an ACPI device object, call acpi_get_gpiod_by_index() for it.
808 * Otherwise (i.e. it is a data-only non-device object), use the property-based
809 * GPIO lookup to get to the GPIO resource with the relevant information and use
810 * that to obtain the GPIO descriptor to return.
811 *
812 * If the GPIO cannot be translated or there is an error an ERR_PTR is
813 * returned.
814 */
815struct gpio_desc *acpi_node_get_gpiod(struct fwnode_handle *fwnode,
816 const char *propname, int index,
817 struct acpi_gpio_info *info)
818{
819 struct acpi_gpio_lookup lookup;
820 struct acpi_device *adev;
821 int ret;
822
823 adev = to_acpi_device_node(fwnode);
824 if (adev)
825 return acpi_get_gpiod_by_index(adev, propname, index, info);
826
827 if (!is_acpi_data_node(fwnode))
828 return ERR_PTR(-ENODEV);
829
830 if (!propname)
831 return ERR_PTR(-EINVAL);
832
833 memset(&lookup, 0, sizeof(lookup));
834 lookup.index = index;
835
836 ret = acpi_gpio_property_lookup(fwnode, propname, index, &lookup);
837 if (ret)
838 return ERR_PTR(ret);
839
840 ret = acpi_gpio_resource_lookup(&lookup, info);
841 return ret ? ERR_PTR(ret) : lookup.desc;
842}
843
844/**
845 * acpi_dev_gpio_irq_get() - Find GpioInt and translate it to Linux IRQ number
846 * @adev: pointer to a ACPI device to get IRQ from
847 * @index: index of GpioInt resource (starting from %0)
848 *
849 * If the device has one or more GpioInt resources, this function can be
850 * used to translate from the GPIO offset in the resource to the Linux IRQ
851 * number.
852 *
853 * The function is idempotent, though each time it runs it will configure GPIO
854 * pin direction according to the flags in GpioInt resource.
855 *
856 * Return: Linux IRQ number (> %0) on success, negative errno on failure.
857 */
858int acpi_dev_gpio_irq_get(struct acpi_device *adev, int index)
859{
860 int idx, i;
861 unsigned int irq_flags;
862 int ret;
863
864 for (i = 0, idx = 0; idx <= index; i++) {
865 struct acpi_gpio_info info;
866 struct gpio_desc *desc;
867
868 desc = acpi_get_gpiod_by_index(adev, NULL, i, &info);
869
870 /* Ignore -EPROBE_DEFER, it only matters if idx matches */
871 if (IS_ERR(desc) && PTR_ERR(desc) != -EPROBE_DEFER)
872 return PTR_ERR(desc);
873
874 if (info.gpioint && idx++ == index) {
875 unsigned long lflags = GPIO_LOOKUP_FLAGS_DEFAULT;
876 char label[32];
877 int irq;
878
879 if (IS_ERR(desc))
880 return PTR_ERR(desc);
881
882 irq = gpiod_to_irq(desc);
883 if (irq < 0)
884 return irq;
885
886 snprintf(label, sizeof(label), "GpioInt() %d", index);
887 ret = gpiod_configure_flags(desc, label, lflags, info.flags);
888 if (ret < 0)
889 return ret;
890
891 irq_flags = acpi_dev_get_irq_type(info.triggering,
892 info.polarity);
893
894 /* Set type if specified and different than the current one */
895 if (irq_flags != IRQ_TYPE_NONE &&
896 irq_flags != irq_get_trigger_type(irq))
897 irq_set_irq_type(irq, irq_flags);
898
899 return irq;
900 }
901
902 }
903 return -ENOENT;
904}
905EXPORT_SYMBOL_GPL(acpi_dev_gpio_irq_get);
906
907static acpi_status
908acpi_gpio_adr_space_handler(u32 function, acpi_physical_address address,
909 u32 bits, u64 *value, void *handler_context,
910 void *region_context)
911{
912 struct acpi_gpio_chip *achip = region_context;
913 struct gpio_chip *chip = achip->chip;
914 struct acpi_resource_gpio *agpio;
915 struct acpi_resource *ares;
916 int pin_index = (int)address;
917 acpi_status status;
918 int length;
919 int i;
920
921 status = acpi_buffer_to_resource(achip->conn_info.connection,
922 achip->conn_info.length, &ares);
923 if (ACPI_FAILURE(status))
924 return status;
925
926 if (WARN_ON(ares->type != ACPI_RESOURCE_TYPE_GPIO)) {
927 ACPI_FREE(ares);
928 return AE_BAD_PARAMETER;
929 }
930
931 agpio = &ares->data.gpio;
932
933 if (WARN_ON(agpio->io_restriction == ACPI_IO_RESTRICT_INPUT &&
934 function == ACPI_WRITE)) {
935 ACPI_FREE(ares);
936 return AE_BAD_PARAMETER;
937 }
938
939 length = min(agpio->pin_table_length, (u16)(pin_index + bits));
940 for (i = pin_index; i < length; ++i) {
941 int pin = agpio->pin_table[i];
942 struct acpi_gpio_connection *conn;
943 struct gpio_desc *desc;
944 bool found;
945
946 mutex_lock(&achip->conn_lock);
947
948 found = false;
949 list_for_each_entry(conn, &achip->conns, node) {
950 if (conn->pin == pin) {
951 found = true;
952 desc = conn->desc;
953 break;
954 }
955 }
956
957 /*
958 * The same GPIO can be shared between operation region and
959 * event but only if the access here is ACPI_READ. In that
960 * case we "borrow" the event GPIO instead.
961 */
962 if (!found && agpio->shareable == ACPI_SHARED &&
963 function == ACPI_READ) {
964 struct acpi_gpio_event *event;
965
966 list_for_each_entry(event, &achip->events, node) {
967 if (event->pin == pin) {
968 desc = event->desc;
969 found = true;
970 break;
971 }
972 }
973 }
974
975 if (!found) {
976 enum gpiod_flags flags = acpi_gpio_to_gpiod_flags(agpio);
977 const char *label = "ACPI:OpRegion";
978
979 desc = gpiochip_request_own_desc(chip, pin, label,
980 GPIO_ACTIVE_HIGH,
981 flags);
982 if (IS_ERR(desc)) {
983 status = AE_ERROR;
984 mutex_unlock(&achip->conn_lock);
985 goto out;
986 }
987
988 conn = kzalloc(sizeof(*conn), GFP_KERNEL);
989 if (!conn) {
990 status = AE_NO_MEMORY;
991 gpiochip_free_own_desc(desc);
992 mutex_unlock(&achip->conn_lock);
993 goto out;
994 }
995
996 conn->pin = pin;
997 conn->desc = desc;
998 list_add_tail(&conn->node, &achip->conns);
999 }
1000
1001 mutex_unlock(&achip->conn_lock);
1002
1003 if (function == ACPI_WRITE)
1004 gpiod_set_raw_value_cansleep(desc,
1005 !!((1 << i) & *value));
1006 else
1007 *value |= (u64)gpiod_get_raw_value_cansleep(desc) << i;
1008 }
1009
1010out:
1011 ACPI_FREE(ares);
1012 return status;
1013}
1014
1015static void acpi_gpiochip_request_regions(struct acpi_gpio_chip *achip)
1016{
1017 struct gpio_chip *chip = achip->chip;
1018 acpi_handle handle = ACPI_HANDLE(chip->parent);
1019 acpi_status status;
1020
1021 INIT_LIST_HEAD(&achip->conns);
1022 mutex_init(&achip->conn_lock);
1023 status = acpi_install_address_space_handler(handle, ACPI_ADR_SPACE_GPIO,
1024 acpi_gpio_adr_space_handler,
1025 NULL, achip);
1026 if (ACPI_FAILURE(status))
1027 dev_err(chip->parent,
1028 "Failed to install GPIO OpRegion handler\n");
1029}
1030
1031static void acpi_gpiochip_free_regions(struct acpi_gpio_chip *achip)
1032{
1033 struct gpio_chip *chip = achip->chip;
1034 acpi_handle handle = ACPI_HANDLE(chip->parent);
1035 struct acpi_gpio_connection *conn, *tmp;
1036 acpi_status status;
1037
1038 status = acpi_remove_address_space_handler(handle, ACPI_ADR_SPACE_GPIO,
1039 acpi_gpio_adr_space_handler);
1040 if (ACPI_FAILURE(status)) {
1041 dev_err(chip->parent,
1042 "Failed to remove GPIO OpRegion handler\n");
1043 return;
1044 }
1045
1046 list_for_each_entry_safe_reverse(conn, tmp, &achip->conns, node) {
1047 gpiochip_free_own_desc(conn->desc);
1048 list_del(&conn->node);
1049 kfree(conn);
1050 }
1051}
1052
1053static struct gpio_desc *
1054acpi_gpiochip_parse_own_gpio(struct acpi_gpio_chip *achip,
1055 struct fwnode_handle *fwnode,
1056 const char **name,
1057 unsigned long *lflags,
1058 enum gpiod_flags *dflags)
1059{
1060 struct gpio_chip *chip = achip->chip;
1061 struct gpio_desc *desc;
1062 u32 gpios[2];
1063 int ret;
1064
1065 *lflags = GPIO_LOOKUP_FLAGS_DEFAULT;
1066 *dflags = 0;
1067 *name = NULL;
1068
1069 ret = fwnode_property_read_u32_array(fwnode, "gpios", gpios,
1070 ARRAY_SIZE(gpios));
1071 if (ret < 0)
1072 return ERR_PTR(ret);
1073
1074 desc = gpiochip_get_desc(chip, gpios[0]);
1075 if (IS_ERR(desc))
1076 return desc;
1077
1078 if (gpios[1])
1079 *lflags |= GPIO_ACTIVE_LOW;
1080
1081 if (fwnode_property_present(fwnode, "input"))
1082 *dflags |= GPIOD_IN;
1083 else if (fwnode_property_present(fwnode, "output-low"))
1084 *dflags |= GPIOD_OUT_LOW;
1085 else if (fwnode_property_present(fwnode, "output-high"))
1086 *dflags |= GPIOD_OUT_HIGH;
1087 else
1088 return ERR_PTR(-EINVAL);
1089
1090 fwnode_property_read_string(fwnode, "line-name", name);
1091
1092 return desc;
1093}
1094
1095static void acpi_gpiochip_scan_gpios(struct acpi_gpio_chip *achip)
1096{
1097 struct gpio_chip *chip = achip->chip;
1098 struct fwnode_handle *fwnode;
1099
1100 device_for_each_child_node(chip->parent, fwnode) {
1101 unsigned long lflags;
1102 enum gpiod_flags dflags;
1103 struct gpio_desc *desc;
1104 const char *name;
1105 int ret;
1106
1107 if (!fwnode_property_present(fwnode, "gpio-hog"))
1108 continue;
1109
1110 desc = acpi_gpiochip_parse_own_gpio(achip, fwnode, &name,
1111 &lflags, &dflags);
1112 if (IS_ERR(desc))
1113 continue;
1114
1115 ret = gpiod_hog(desc, name, lflags, dflags);
1116 if (ret) {
1117 dev_err(chip->parent, "Failed to hog GPIO\n");
1118 fwnode_handle_put(fwnode);
1119 return;
1120 }
1121 }
1122}
1123
1124void acpi_gpiochip_add(struct gpio_chip *chip)
1125{
1126 struct acpi_gpio_chip *acpi_gpio;
1127 acpi_handle handle;
1128 acpi_status status;
1129
1130 if (!chip || !chip->parent)
1131 return;
1132
1133 handle = ACPI_HANDLE(chip->parent);
1134 if (!handle)
1135 return;
1136
1137 acpi_gpio = kzalloc(sizeof(*acpi_gpio), GFP_KERNEL);
1138 if (!acpi_gpio) {
1139 dev_err(chip->parent,
1140 "Failed to allocate memory for ACPI GPIO chip\n");
1141 return;
1142 }
1143
1144 acpi_gpio->chip = chip;
1145 INIT_LIST_HEAD(&acpi_gpio->events);
1146 INIT_LIST_HEAD(&acpi_gpio->deferred_req_irqs_list_entry);
1147
1148 status = acpi_attach_data(handle, acpi_gpio_chip_dh, acpi_gpio);
1149 if (ACPI_FAILURE(status)) {
1150 dev_err(chip->parent, "Failed to attach ACPI GPIO chip\n");
1151 kfree(acpi_gpio);
1152 return;
1153 }
1154
1155 if (!chip->names)
1156 devprop_gpiochip_set_names(chip, dev_fwnode(chip->parent));
1157
1158 acpi_gpiochip_request_regions(acpi_gpio);
1159 acpi_gpiochip_scan_gpios(acpi_gpio);
1160 acpi_walk_dep_device_list(handle);
1161}
1162
1163void acpi_gpiochip_remove(struct gpio_chip *chip)
1164{
1165 struct acpi_gpio_chip *acpi_gpio;
1166 acpi_handle handle;
1167 acpi_status status;
1168
1169 if (!chip || !chip->parent)
1170 return;
1171
1172 handle = ACPI_HANDLE(chip->parent);
1173 if (!handle)
1174 return;
1175
1176 status = acpi_get_data(handle, acpi_gpio_chip_dh, (void **)&acpi_gpio);
1177 if (ACPI_FAILURE(status)) {
1178 dev_warn(chip->parent, "Failed to retrieve ACPI GPIO chip\n");
1179 return;
1180 }
1181
1182 acpi_gpiochip_free_regions(acpi_gpio);
1183
1184 acpi_detach_data(handle, acpi_gpio_chip_dh);
1185 kfree(acpi_gpio);
1186}
1187
1188static int acpi_gpio_package_count(const union acpi_object *obj)
1189{
1190 const union acpi_object *element = obj->package.elements;
1191 const union acpi_object *end = element + obj->package.count;
1192 unsigned int count = 0;
1193
1194 while (element < end) {
1195 switch (element->type) {
1196 case ACPI_TYPE_LOCAL_REFERENCE:
1197 element += 3;
1198 /* Fallthrough */
1199 case ACPI_TYPE_INTEGER:
1200 element++;
1201 count++;
1202 break;
1203
1204 default:
1205 return -EPROTO;
1206 }
1207 }
1208
1209 return count;
1210}
1211
1212static int acpi_find_gpio_count(struct acpi_resource *ares, void *data)
1213{
1214 unsigned int *count = data;
1215
1216 if (ares->type == ACPI_RESOURCE_TYPE_GPIO)
1217 *count += ares->data.gpio.pin_table_length;
1218
1219 return 1;
1220}
1221
1222/**
1223 * acpi_gpio_count - count the GPIOs associated with a device / function
1224 * @dev: GPIO consumer, can be %NULL for system-global GPIOs
1225 * @con_id: function within the GPIO consumer
1226 *
1227 * Return:
1228 * The number of GPIOs associated with a device / function or %-ENOENT,
1229 * if no GPIO has been assigned to the requested function.
1230 */
1231int acpi_gpio_count(struct device *dev, const char *con_id)
1232{
1233 struct acpi_device *adev = ACPI_COMPANION(dev);
1234 const union acpi_object *obj;
1235 const struct acpi_gpio_mapping *gm;
1236 int count = -ENOENT;
1237 int ret;
1238 char propname[32];
1239 unsigned int i;
1240
1241 /* Try first from _DSD */
1242 for (i = 0; i < ARRAY_SIZE(gpio_suffixes); i++) {
1243 if (con_id)
1244 snprintf(propname, sizeof(propname), "%s-%s",
1245 con_id, gpio_suffixes[i]);
1246 else
1247 snprintf(propname, sizeof(propname), "%s",
1248 gpio_suffixes[i]);
1249
1250 ret = acpi_dev_get_property(adev, propname, ACPI_TYPE_ANY,
1251 &obj);
1252 if (ret == 0) {
1253 if (obj->type == ACPI_TYPE_LOCAL_REFERENCE)
1254 count = 1;
1255 else if (obj->type == ACPI_TYPE_PACKAGE)
1256 count = acpi_gpio_package_count(obj);
1257 } else if (adev->driver_gpios) {
1258 for (gm = adev->driver_gpios; gm->name; gm++)
1259 if (strcmp(propname, gm->name) == 0) {
1260 count = gm->size;
1261 break;
1262 }
1263 }
1264 if (count > 0)
1265 break;
1266 }
1267
1268 /* Then from plain _CRS GPIOs */
1269 if (count < 0) {
1270 struct list_head resource_list;
1271 unsigned int crs_count = 0;
1272
1273 if (!acpi_can_fallback_to_crs(adev, con_id))
1274 return count;
1275
1276 INIT_LIST_HEAD(&resource_list);
1277 acpi_dev_get_resources(adev, &resource_list,
1278 acpi_find_gpio_count, &crs_count);
1279 acpi_dev_free_resource_list(&resource_list);
1280 if (crs_count > 0)
1281 count = crs_count;
1282 }
1283 return count ? count : -ENOENT;
1284}
1285
1286/* Run deferred acpi_gpiochip_request_irqs() */
1287static int acpi_gpio_handle_deferred_request_irqs(void)
1288{
1289 struct acpi_gpio_chip *acpi_gpio, *tmp;
1290
1291 mutex_lock(&acpi_gpio_deferred_req_irqs_lock);
1292 list_for_each_entry_safe(acpi_gpio, tmp,
1293 &acpi_gpio_deferred_req_irqs_list,
1294 deferred_req_irqs_list_entry)
1295 acpi_gpiochip_request_irqs(acpi_gpio);
1296
1297 acpi_gpio_deferred_req_irqs_done = true;
1298 mutex_unlock(&acpi_gpio_deferred_req_irqs_lock);
1299
1300 return 0;
1301}
1302/* We must use _sync so that this runs after the first deferred_probe run */
1303late_initcall_sync(acpi_gpio_handle_deferred_request_irqs);
1304
1305static const struct dmi_system_id run_edge_events_on_boot_blacklist[] = {
1306 {
1307 /*
1308 * The Minix Neo Z83-4 has a micro-USB-B id-pin handler for
1309 * a non existing micro-USB-B connector which puts the HDMI
1310 * DDC pins in GPIO mode, breaking HDMI support.
1311 */
1312 .matches = {
1313 DMI_MATCH(DMI_SYS_VENDOR, "MINIX"),
1314 DMI_MATCH(DMI_PRODUCT_NAME, "Z83-4"),
1315 }
1316 },
1317 {
1318 /*
1319 * The Terra Pad 1061 has a micro-USB-B id-pin handler, which
1320 * instead of controlling the actual micro-USB-B turns the 5V
1321 * boost for its USB-A connector off. The actual micro-USB-B
1322 * connector is wired for charging only.
1323 */
1324 .matches = {
1325 DMI_MATCH(DMI_SYS_VENDOR, "Wortmann_AG"),
1326 DMI_MATCH(DMI_PRODUCT_NAME, "TERRA_PAD_1061"),
1327 }
1328 },
1329 {} /* Terminating entry */
1330};
1331
1332static int acpi_gpio_setup_params(void)
1333{
1334 if (run_edge_events_on_boot < 0) {
1335 if (dmi_check_system(run_edge_events_on_boot_blacklist))
1336 run_edge_events_on_boot = 0;
1337 else
1338 run_edge_events_on_boot = 1;
1339 }
1340
1341 return 0;
1342}
1343
1344/* Directly after dmi_setup() which runs as core_initcall() */
1345postcore_initcall(acpi_gpio_setup_params);