xref: /openbmc/linux/drivers/gpio/gpiolib-acpi.c (revision 4e042f02)
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/acpi.h>
11 #include <linux/dmi.h>
12 #include <linux/errno.h>
13 #include <linux/export.h>
14 #include <linux/interrupt.h>
15 #include <linux/irq.h>
16 #include <linux/mutex.h>
17 #include <linux/pinctrl/pinctrl.h>
18 
19 #include <linux/gpio/consumer.h>
20 #include <linux/gpio/driver.h>
21 #include <linux/gpio/machine.h>
22 
23 #include "gpiolib.h"
24 #include "gpiolib-acpi.h"
25 
26 static int run_edge_events_on_boot = -1;
27 module_param(run_edge_events_on_boot, int, 0444);
28 MODULE_PARM_DESC(run_edge_events_on_boot,
29 		 "Run edge _AEI event-handlers at boot: 0=no, 1=yes, -1=auto");
30 
31 static char *ignore_wake;
32 module_param(ignore_wake, charp, 0444);
33 MODULE_PARM_DESC(ignore_wake,
34 		 "controller@pin combos on which to ignore the ACPI wake flag "
35 		 "ignore_wake=controller@pin[,controller@pin[,...]]");
36 
37 static char *ignore_interrupt;
38 module_param(ignore_interrupt, charp, 0444);
39 MODULE_PARM_DESC(ignore_interrupt,
40 		 "controller@pin combos on which to ignore interrupt "
41 		 "ignore_interrupt=controller@pin[,controller@pin[,...]]");
42 
43 struct acpi_gpiolib_dmi_quirk {
44 	bool no_edge_events_on_boot;
45 	char *ignore_wake;
46 	char *ignore_interrupt;
47 };
48 
49 /**
50  * struct acpi_gpio_event - ACPI GPIO event handler data
51  *
52  * @node:	  list-entry of the events list of the struct acpi_gpio_chip
53  * @handle:	  handle of ACPI method to execute when the IRQ triggers
54  * @handler:	  handler function to pass to request_irq() when requesting the IRQ
55  * @pin:	  GPIO pin number on the struct gpio_chip
56  * @irq:	  Linux IRQ number for the event, for request_irq() / free_irq()
57  * @irqflags:	  flags to pass to request_irq() when requesting the IRQ
58  * @irq_is_wake:  If the ACPI flags indicate the IRQ is a wakeup source
59  * @irq_requested:True if request_irq() has been done
60  * @desc:	  struct gpio_desc for the GPIO pin for this event
61  */
62 struct acpi_gpio_event {
63 	struct list_head node;
64 	acpi_handle handle;
65 	irq_handler_t handler;
66 	unsigned int pin;
67 	unsigned int irq;
68 	unsigned long irqflags;
69 	bool irq_is_wake;
70 	bool irq_requested;
71 	struct gpio_desc *desc;
72 };
73 
74 struct acpi_gpio_connection {
75 	struct list_head node;
76 	unsigned int pin;
77 	struct gpio_desc *desc;
78 };
79 
80 struct acpi_gpio_chip {
81 	/*
82 	 * ACPICA requires that the first field of the context parameter
83 	 * passed to acpi_install_address_space_handler() is large enough
84 	 * to hold struct acpi_connection_info.
85 	 */
86 	struct acpi_connection_info conn_info;
87 	struct list_head conns;
88 	struct mutex conn_lock;
89 	struct gpio_chip *chip;
90 	struct list_head events;
91 	struct list_head deferred_req_irqs_list_entry;
92 };
93 
94 /**
95  * struct acpi_gpio_info - ACPI GPIO specific information
96  * @adev: reference to ACPI device which consumes GPIO resource
97  * @flags: GPIO initialization flags
98  * @gpioint: if %true this GPIO is of type GpioInt otherwise type is GpioIo
99  * @pin_config: pin bias as provided by ACPI
100  * @polarity: interrupt polarity as provided by ACPI
101  * @triggering: triggering type as provided by ACPI
102  * @wake_capable: wake capability as provided by ACPI
103  * @debounce: debounce timeout as provided by ACPI
104  * @quirks: Linux specific quirks as provided by struct acpi_gpio_mapping
105  */
106 struct acpi_gpio_info {
107 	struct acpi_device *adev;
108 	enum gpiod_flags flags;
109 	bool gpioint;
110 	int pin_config;
111 	int polarity;
112 	int triggering;
113 	bool wake_capable;
114 	unsigned int debounce;
115 	unsigned int quirks;
116 };
117 
118 /*
119  * For GPIO chips which call acpi_gpiochip_request_interrupts() before late_init
120  * (so builtin drivers) we register the ACPI GpioInt IRQ handlers from a
121  * late_initcall_sync() handler, so that other builtin drivers can register their
122  * OpRegions before the event handlers can run. This list contains GPIO chips
123  * for which the acpi_gpiochip_request_irqs() call has been deferred.
124  */
125 static DEFINE_MUTEX(acpi_gpio_deferred_req_irqs_lock);
126 static LIST_HEAD(acpi_gpio_deferred_req_irqs_list);
127 static bool acpi_gpio_deferred_req_irqs_done;
128 
129 static int acpi_gpiochip_find(struct gpio_chip *gc, void *data)
130 {
131 	return device_match_acpi_handle(&gc->gpiodev->dev, data);
132 }
133 
134 /**
135  * acpi_get_gpiod() - Translate ACPI GPIO pin to GPIO descriptor usable with GPIO API
136  * @path:	ACPI GPIO controller full path name, (e.g. "\\_SB.GPO1")
137  * @pin:	ACPI GPIO pin number (0-based, controller-relative)
138  *
139  * Return: GPIO descriptor to use with Linux generic GPIO API, or ERR_PTR
140  * error value. Specifically returns %-EPROBE_DEFER if the referenced GPIO
141  * controller does not have GPIO chip registered at the moment. This is to
142  * support probe deferral.
143  */
144 static struct gpio_desc *acpi_get_gpiod(char *path, unsigned int pin)
145 {
146 	struct gpio_chip *chip;
147 	acpi_handle handle;
148 	acpi_status status;
149 
150 	status = acpi_get_handle(NULL, path, &handle);
151 	if (ACPI_FAILURE(status))
152 		return ERR_PTR(-ENODEV);
153 
154 	chip = gpiochip_find(handle, acpi_gpiochip_find);
155 	if (!chip)
156 		return ERR_PTR(-EPROBE_DEFER);
157 
158 	return gpiochip_get_desc(chip, pin);
159 }
160 
161 /**
162  * acpi_get_and_request_gpiod - Translate ACPI GPIO pin to GPIO descriptor and
163  *                              hold a refcount to the GPIO device.
164  * @path:      ACPI GPIO controller full path name, (e.g. "\\_SB.GPO1")
165  * @pin:       ACPI GPIO pin number (0-based, controller-relative)
166  * @label:     Label to pass to gpiod_request()
167  *
168  * This function is a simple pass-through to acpi_get_gpiod(), except that
169  * as it is intended for use outside of the GPIO layer (in a similar fashion to
170  * gpiod_get_index() for example) it also holds a reference to the GPIO device.
171  */
172 struct gpio_desc *acpi_get_and_request_gpiod(char *path, unsigned int pin, char *label)
173 {
174 	struct gpio_desc *gpio;
175 	int ret;
176 
177 	gpio = acpi_get_gpiod(path, pin);
178 	if (IS_ERR(gpio))
179 		return gpio;
180 
181 	ret = gpiod_request(gpio, label);
182 	if (ret)
183 		return ERR_PTR(ret);
184 
185 	return gpio;
186 }
187 EXPORT_SYMBOL_GPL(acpi_get_and_request_gpiod);
188 
189 static irqreturn_t acpi_gpio_irq_handler(int irq, void *data)
190 {
191 	struct acpi_gpio_event *event = data;
192 
193 	acpi_evaluate_object(event->handle, NULL, NULL, NULL);
194 
195 	return IRQ_HANDLED;
196 }
197 
198 static irqreturn_t acpi_gpio_irq_handler_evt(int irq, void *data)
199 {
200 	struct acpi_gpio_event *event = data;
201 
202 	acpi_execute_simple_method(event->handle, NULL, event->pin);
203 
204 	return IRQ_HANDLED;
205 }
206 
207 static void acpi_gpio_chip_dh(acpi_handle handle, void *data)
208 {
209 	/* The address of this function is used as a key. */
210 }
211 
212 bool acpi_gpio_get_irq_resource(struct acpi_resource *ares,
213 				struct acpi_resource_gpio **agpio)
214 {
215 	struct acpi_resource_gpio *gpio;
216 
217 	if (ares->type != ACPI_RESOURCE_TYPE_GPIO)
218 		return false;
219 
220 	gpio = &ares->data.gpio;
221 	if (gpio->connection_type != ACPI_RESOURCE_GPIO_TYPE_INT)
222 		return false;
223 
224 	*agpio = gpio;
225 	return true;
226 }
227 EXPORT_SYMBOL_GPL(acpi_gpio_get_irq_resource);
228 
229 /**
230  * acpi_gpio_get_io_resource - Fetch details of an ACPI resource if it is a GPIO
231  *			       I/O resource or return False if not.
232  * @ares:	Pointer to the ACPI resource to fetch
233  * @agpio:	Pointer to a &struct acpi_resource_gpio to store the output pointer
234  */
235 bool acpi_gpio_get_io_resource(struct acpi_resource *ares,
236 			       struct acpi_resource_gpio **agpio)
237 {
238 	struct acpi_resource_gpio *gpio;
239 
240 	if (ares->type != ACPI_RESOURCE_TYPE_GPIO)
241 		return false;
242 
243 	gpio = &ares->data.gpio;
244 	if (gpio->connection_type != ACPI_RESOURCE_GPIO_TYPE_IO)
245 		return false;
246 
247 	*agpio = gpio;
248 	return true;
249 }
250 EXPORT_SYMBOL_GPL(acpi_gpio_get_io_resource);
251 
252 static void acpi_gpiochip_request_irq(struct acpi_gpio_chip *acpi_gpio,
253 				      struct acpi_gpio_event *event)
254 {
255 	struct device *parent = acpi_gpio->chip->parent;
256 	int ret, value;
257 
258 	ret = request_threaded_irq(event->irq, NULL, event->handler,
259 				   event->irqflags | IRQF_ONESHOT, "ACPI:Event", event);
260 	if (ret) {
261 		dev_err(parent, "Failed to setup interrupt handler for %d\n", event->irq);
262 		return;
263 	}
264 
265 	if (event->irq_is_wake)
266 		enable_irq_wake(event->irq);
267 
268 	event->irq_requested = true;
269 
270 	/* Make sure we trigger the initial state of edge-triggered IRQs */
271 	if (run_edge_events_on_boot &&
272 	    (event->irqflags & (IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING))) {
273 		value = gpiod_get_raw_value_cansleep(event->desc);
274 		if (((event->irqflags & IRQF_TRIGGER_RISING) && value == 1) ||
275 		    ((event->irqflags & IRQF_TRIGGER_FALLING) && value == 0))
276 			event->handler(event->irq, event);
277 	}
278 }
279 
280 static void acpi_gpiochip_request_irqs(struct acpi_gpio_chip *acpi_gpio)
281 {
282 	struct acpi_gpio_event *event;
283 
284 	list_for_each_entry(event, &acpi_gpio->events, node)
285 		acpi_gpiochip_request_irq(acpi_gpio, event);
286 }
287 
288 static enum gpiod_flags
289 acpi_gpio_to_gpiod_flags(const struct acpi_resource_gpio *agpio, int polarity)
290 {
291 	/* GpioInt() implies input configuration */
292 	if (agpio->connection_type == ACPI_RESOURCE_GPIO_TYPE_INT)
293 		return GPIOD_IN;
294 
295 	switch (agpio->io_restriction) {
296 	case ACPI_IO_RESTRICT_INPUT:
297 		return GPIOD_IN;
298 	case ACPI_IO_RESTRICT_OUTPUT:
299 		/*
300 		 * ACPI GPIO resources don't contain an initial value for the
301 		 * GPIO. Therefore we deduce that value from the pull field
302 		 * and the polarity instead. If the pin is pulled up we assume
303 		 * default to be high, if it is pulled down we assume default
304 		 * to be low, otherwise we leave pin untouched. For active low
305 		 * polarity values will be switched. See also
306 		 * Documentation/firmware-guide/acpi/gpio-properties.rst.
307 		 */
308 		switch (agpio->pin_config) {
309 		case ACPI_PIN_CONFIG_PULLUP:
310 			return polarity == GPIO_ACTIVE_LOW ? GPIOD_OUT_LOW : GPIOD_OUT_HIGH;
311 		case ACPI_PIN_CONFIG_PULLDOWN:
312 			return polarity == GPIO_ACTIVE_LOW ? GPIOD_OUT_HIGH : GPIOD_OUT_LOW;
313 		default:
314 			break;
315 		}
316 		break;
317 	default:
318 		break;
319 	}
320 
321 	/*
322 	 * Assume that the BIOS has configured the direction and pull
323 	 * accordingly.
324 	 */
325 	return GPIOD_ASIS;
326 }
327 
328 static struct gpio_desc *acpi_request_own_gpiod(struct gpio_chip *chip,
329 						struct acpi_resource_gpio *agpio,
330 						unsigned int index,
331 						const char *label)
332 {
333 	int polarity = GPIO_ACTIVE_HIGH;
334 	enum gpiod_flags flags = acpi_gpio_to_gpiod_flags(agpio, polarity);
335 	unsigned int pin = agpio->pin_table[index];
336 	struct gpio_desc *desc;
337 	int ret;
338 
339 	desc = gpiochip_request_own_desc(chip, pin, label, polarity, flags);
340 	if (IS_ERR(desc))
341 		return desc;
342 
343 	/* ACPI uses hundredths of milliseconds units */
344 	ret = gpio_set_debounce_timeout(desc, agpio->debounce_timeout * 10);
345 	if (ret)
346 		dev_warn(chip->parent,
347 			 "Failed to set debounce-timeout for pin 0x%04X, err %d\n",
348 			 pin, ret);
349 
350 	return desc;
351 }
352 
353 static bool acpi_gpio_in_ignore_list(const char *ignore_list, const char *controller_in,
354 				     unsigned int pin_in)
355 {
356 	const char *controller, *pin_str;
357 	unsigned int pin;
358 	char *endp;
359 	int len;
360 
361 	controller = ignore_list;
362 	while (controller) {
363 		pin_str = strchr(controller, '@');
364 		if (!pin_str)
365 			goto err;
366 
367 		len = pin_str - controller;
368 		if (len == strlen(controller_in) &&
369 		    strncmp(controller, controller_in, len) == 0) {
370 			pin = simple_strtoul(pin_str + 1, &endp, 10);
371 			if (*endp != 0 && *endp != ',')
372 				goto err;
373 
374 			if (pin == pin_in)
375 				return true;
376 		}
377 
378 		controller = strchr(controller, ',');
379 		if (controller)
380 			controller++;
381 	}
382 
383 	return false;
384 err:
385 	pr_err_once("Error: Invalid value for gpiolib_acpi.ignore_...: %s\n", ignore_list);
386 	return false;
387 }
388 
389 static bool acpi_gpio_irq_is_wake(struct device *parent,
390 				  const struct acpi_resource_gpio *agpio)
391 {
392 	unsigned int pin = agpio->pin_table[0];
393 
394 	if (agpio->wake_capable != ACPI_WAKE_CAPABLE)
395 		return false;
396 
397 	if (acpi_gpio_in_ignore_list(ignore_wake, dev_name(parent), pin)) {
398 		dev_info(parent, "Ignoring wakeup on pin %u\n", pin);
399 		return false;
400 	}
401 
402 	return true;
403 }
404 
405 /* Always returns AE_OK so that we keep looping over the resources */
406 static acpi_status acpi_gpiochip_alloc_event(struct acpi_resource *ares,
407 					     void *context)
408 {
409 	struct acpi_gpio_chip *acpi_gpio = context;
410 	struct gpio_chip *chip = acpi_gpio->chip;
411 	struct acpi_resource_gpio *agpio;
412 	acpi_handle handle, evt_handle;
413 	struct acpi_gpio_event *event;
414 	irq_handler_t handler = NULL;
415 	struct gpio_desc *desc;
416 	unsigned int pin;
417 	int ret, irq;
418 
419 	if (!acpi_gpio_get_irq_resource(ares, &agpio))
420 		return AE_OK;
421 
422 	handle = ACPI_HANDLE(chip->parent);
423 	pin = agpio->pin_table[0];
424 
425 	if (pin <= 255) {
426 		char ev_name[8];
427 		sprintf(ev_name, "_%c%02X",
428 			agpio->triggering == ACPI_EDGE_SENSITIVE ? 'E' : 'L',
429 			pin);
430 		if (ACPI_SUCCESS(acpi_get_handle(handle, ev_name, &evt_handle)))
431 			handler = acpi_gpio_irq_handler;
432 	}
433 	if (!handler) {
434 		if (ACPI_SUCCESS(acpi_get_handle(handle, "_EVT", &evt_handle)))
435 			handler = acpi_gpio_irq_handler_evt;
436 	}
437 	if (!handler)
438 		return AE_OK;
439 
440 	desc = acpi_request_own_gpiod(chip, agpio, 0, "ACPI:Event");
441 	if (IS_ERR(desc)) {
442 		dev_err(chip->parent,
443 			"Failed to request GPIO for pin 0x%04X, err %ld\n",
444 			pin, PTR_ERR(desc));
445 		return AE_OK;
446 	}
447 
448 	ret = gpiochip_lock_as_irq(chip, pin);
449 	if (ret) {
450 		dev_err(chip->parent,
451 			"Failed to lock GPIO pin 0x%04X as interrupt, err %d\n",
452 			pin, ret);
453 		goto fail_free_desc;
454 	}
455 
456 	irq = gpiod_to_irq(desc);
457 	if (irq < 0) {
458 		dev_err(chip->parent,
459 			"Failed to translate GPIO pin 0x%04X to IRQ, err %d\n",
460 			pin, irq);
461 		goto fail_unlock_irq;
462 	}
463 
464 	if (acpi_gpio_in_ignore_list(ignore_interrupt, dev_name(chip->parent), pin)) {
465 		dev_info(chip->parent, "Ignoring interrupt on pin %u\n", pin);
466 		return AE_OK;
467 	}
468 
469 	event = kzalloc(sizeof(*event), GFP_KERNEL);
470 	if (!event)
471 		goto fail_unlock_irq;
472 
473 	event->irqflags = IRQF_ONESHOT;
474 	if (agpio->triggering == ACPI_LEVEL_SENSITIVE) {
475 		if (agpio->polarity == ACPI_ACTIVE_HIGH)
476 			event->irqflags |= IRQF_TRIGGER_HIGH;
477 		else
478 			event->irqflags |= IRQF_TRIGGER_LOW;
479 	} else {
480 		switch (agpio->polarity) {
481 		case ACPI_ACTIVE_HIGH:
482 			event->irqflags |= IRQF_TRIGGER_RISING;
483 			break;
484 		case ACPI_ACTIVE_LOW:
485 			event->irqflags |= IRQF_TRIGGER_FALLING;
486 			break;
487 		default:
488 			event->irqflags |= IRQF_TRIGGER_RISING |
489 					   IRQF_TRIGGER_FALLING;
490 			break;
491 		}
492 	}
493 
494 	event->handle = evt_handle;
495 	event->handler = handler;
496 	event->irq = irq;
497 	event->irq_is_wake = acpi_gpio_irq_is_wake(chip->parent, agpio);
498 	event->pin = pin;
499 	event->desc = desc;
500 
501 	list_add_tail(&event->node, &acpi_gpio->events);
502 
503 	return AE_OK;
504 
505 fail_unlock_irq:
506 	gpiochip_unlock_as_irq(chip, pin);
507 fail_free_desc:
508 	gpiochip_free_own_desc(desc);
509 
510 	return AE_OK;
511 }
512 
513 /**
514  * acpi_gpiochip_request_interrupts() - Register isr for gpio chip ACPI events
515  * @chip:      GPIO chip
516  *
517  * ACPI5 platforms can use GPIO signaled ACPI events. These GPIO interrupts are
518  * handled by ACPI event methods which need to be called from the GPIO
519  * chip's interrupt handler. acpi_gpiochip_request_interrupts() finds out which
520  * GPIO pins have ACPI event methods and assigns interrupt handlers that calls
521  * the ACPI event methods for those pins.
522  */
523 void acpi_gpiochip_request_interrupts(struct gpio_chip *chip)
524 {
525 	struct acpi_gpio_chip *acpi_gpio;
526 	acpi_handle handle;
527 	acpi_status status;
528 	bool defer;
529 
530 	if (!chip->parent || !chip->to_irq)
531 		return;
532 
533 	handle = ACPI_HANDLE(chip->parent);
534 	if (!handle)
535 		return;
536 
537 	status = acpi_get_data(handle, acpi_gpio_chip_dh, (void **)&acpi_gpio);
538 	if (ACPI_FAILURE(status))
539 		return;
540 
541 	if (acpi_quirk_skip_gpio_event_handlers())
542 		return;
543 
544 	acpi_walk_resources(handle, METHOD_NAME__AEI,
545 			    acpi_gpiochip_alloc_event, acpi_gpio);
546 
547 	mutex_lock(&acpi_gpio_deferred_req_irqs_lock);
548 	defer = !acpi_gpio_deferred_req_irqs_done;
549 	if (defer)
550 		list_add(&acpi_gpio->deferred_req_irqs_list_entry,
551 			 &acpi_gpio_deferred_req_irqs_list);
552 	mutex_unlock(&acpi_gpio_deferred_req_irqs_lock);
553 
554 	if (defer)
555 		return;
556 
557 	acpi_gpiochip_request_irqs(acpi_gpio);
558 }
559 EXPORT_SYMBOL_GPL(acpi_gpiochip_request_interrupts);
560 
561 /**
562  * acpi_gpiochip_free_interrupts() - Free GPIO ACPI event interrupts.
563  * @chip:      GPIO chip
564  *
565  * Free interrupts associated with GPIO ACPI event method for the given
566  * GPIO chip.
567  */
568 void acpi_gpiochip_free_interrupts(struct gpio_chip *chip)
569 {
570 	struct acpi_gpio_chip *acpi_gpio;
571 	struct acpi_gpio_event *event, *ep;
572 	acpi_handle handle;
573 	acpi_status status;
574 
575 	if (!chip->parent || !chip->to_irq)
576 		return;
577 
578 	handle = ACPI_HANDLE(chip->parent);
579 	if (!handle)
580 		return;
581 
582 	status = acpi_get_data(handle, acpi_gpio_chip_dh, (void **)&acpi_gpio);
583 	if (ACPI_FAILURE(status))
584 		return;
585 
586 	mutex_lock(&acpi_gpio_deferred_req_irqs_lock);
587 	if (!list_empty(&acpi_gpio->deferred_req_irqs_list_entry))
588 		list_del_init(&acpi_gpio->deferred_req_irqs_list_entry);
589 	mutex_unlock(&acpi_gpio_deferred_req_irqs_lock);
590 
591 	list_for_each_entry_safe_reverse(event, ep, &acpi_gpio->events, node) {
592 		if (event->irq_requested) {
593 			if (event->irq_is_wake)
594 				disable_irq_wake(event->irq);
595 
596 			free_irq(event->irq, event);
597 		}
598 
599 		gpiochip_unlock_as_irq(chip, event->pin);
600 		gpiochip_free_own_desc(event->desc);
601 		list_del(&event->node);
602 		kfree(event);
603 	}
604 }
605 EXPORT_SYMBOL_GPL(acpi_gpiochip_free_interrupts);
606 
607 int acpi_dev_add_driver_gpios(struct acpi_device *adev,
608 			      const struct acpi_gpio_mapping *gpios)
609 {
610 	if (adev && gpios) {
611 		adev->driver_gpios = gpios;
612 		return 0;
613 	}
614 	return -EINVAL;
615 }
616 EXPORT_SYMBOL_GPL(acpi_dev_add_driver_gpios);
617 
618 void acpi_dev_remove_driver_gpios(struct acpi_device *adev)
619 {
620 	if (adev)
621 		adev->driver_gpios = NULL;
622 }
623 EXPORT_SYMBOL_GPL(acpi_dev_remove_driver_gpios);
624 
625 static void acpi_dev_release_driver_gpios(void *adev)
626 {
627 	acpi_dev_remove_driver_gpios(adev);
628 }
629 
630 int devm_acpi_dev_add_driver_gpios(struct device *dev,
631 				   const struct acpi_gpio_mapping *gpios)
632 {
633 	struct acpi_device *adev = ACPI_COMPANION(dev);
634 	int ret;
635 
636 	ret = acpi_dev_add_driver_gpios(adev, gpios);
637 	if (ret)
638 		return ret;
639 
640 	return devm_add_action_or_reset(dev, acpi_dev_release_driver_gpios, adev);
641 }
642 EXPORT_SYMBOL_GPL(devm_acpi_dev_add_driver_gpios);
643 
644 static bool acpi_get_driver_gpio_data(struct acpi_device *adev,
645 				      const char *name, int index,
646 				      struct fwnode_reference_args *args,
647 				      unsigned int *quirks)
648 {
649 	const struct acpi_gpio_mapping *gm;
650 
651 	if (!adev || !adev->driver_gpios)
652 		return false;
653 
654 	for (gm = adev->driver_gpios; gm->name; gm++)
655 		if (!strcmp(name, gm->name) && gm->data && index < gm->size) {
656 			const struct acpi_gpio_params *par = gm->data + index;
657 
658 			args->fwnode = acpi_fwnode_handle(adev);
659 			args->args[0] = par->crs_entry_index;
660 			args->args[1] = par->line_index;
661 			args->args[2] = par->active_low;
662 			args->nargs = 3;
663 
664 			*quirks = gm->quirks;
665 			return true;
666 		}
667 
668 	return false;
669 }
670 
671 static int
672 __acpi_gpio_update_gpiod_flags(enum gpiod_flags *flags, enum gpiod_flags update)
673 {
674 	const enum gpiod_flags mask =
675 		GPIOD_FLAGS_BIT_DIR_SET | GPIOD_FLAGS_BIT_DIR_OUT |
676 		GPIOD_FLAGS_BIT_DIR_VAL;
677 	int ret = 0;
678 
679 	/*
680 	 * Check if the BIOS has IoRestriction with explicitly set direction
681 	 * and update @flags accordingly. Otherwise use whatever caller asked
682 	 * for.
683 	 */
684 	if (update & GPIOD_FLAGS_BIT_DIR_SET) {
685 		enum gpiod_flags diff = *flags ^ update;
686 
687 		/*
688 		 * Check if caller supplied incompatible GPIO initialization
689 		 * flags.
690 		 *
691 		 * Return %-EINVAL to notify that firmware has different
692 		 * settings and we are going to use them.
693 		 */
694 		if (((*flags & GPIOD_FLAGS_BIT_DIR_SET) && (diff & GPIOD_FLAGS_BIT_DIR_OUT)) ||
695 		    ((*flags & GPIOD_FLAGS_BIT_DIR_OUT) && (diff & GPIOD_FLAGS_BIT_DIR_VAL)))
696 			ret = -EINVAL;
697 		*flags = (*flags & ~mask) | (update & mask);
698 	}
699 	return ret;
700 }
701 
702 static int acpi_gpio_update_gpiod_flags(enum gpiod_flags *flags,
703 				        struct acpi_gpio_info *info)
704 {
705 	struct device *dev = &info->adev->dev;
706 	enum gpiod_flags old = *flags;
707 	int ret;
708 
709 	ret = __acpi_gpio_update_gpiod_flags(&old, info->flags);
710 	if (info->quirks & ACPI_GPIO_QUIRK_NO_IO_RESTRICTION) {
711 		if (ret)
712 			dev_warn(dev, FW_BUG "GPIO not in correct mode, fixing\n");
713 	} else {
714 		if (ret)
715 			dev_dbg(dev, "Override GPIO initialization flags\n");
716 		*flags = old;
717 	}
718 
719 	return ret;
720 }
721 
722 static int acpi_gpio_update_gpiod_lookup_flags(unsigned long *lookupflags,
723 					       struct acpi_gpio_info *info)
724 {
725 	switch (info->pin_config) {
726 	case ACPI_PIN_CONFIG_PULLUP:
727 		*lookupflags |= GPIO_PULL_UP;
728 		break;
729 	case ACPI_PIN_CONFIG_PULLDOWN:
730 		*lookupflags |= GPIO_PULL_DOWN;
731 		break;
732 	case ACPI_PIN_CONFIG_NOPULL:
733 		*lookupflags |= GPIO_PULL_DISABLE;
734 		break;
735 	default:
736 		break;
737 	}
738 
739 	if (info->polarity == GPIO_ACTIVE_LOW)
740 		*lookupflags |= GPIO_ACTIVE_LOW;
741 
742 	return 0;
743 }
744 
745 struct acpi_gpio_lookup {
746 	struct acpi_gpio_info info;
747 	int index;
748 	u16 pin_index;
749 	bool active_low;
750 	struct gpio_desc *desc;
751 	int n;
752 };
753 
754 static int acpi_populate_gpio_lookup(struct acpi_resource *ares, void *data)
755 {
756 	struct acpi_gpio_lookup *lookup = data;
757 
758 	if (ares->type != ACPI_RESOURCE_TYPE_GPIO)
759 		return 1;
760 
761 	if (!lookup->desc) {
762 		const struct acpi_resource_gpio *agpio = &ares->data.gpio;
763 		bool gpioint = agpio->connection_type == ACPI_RESOURCE_GPIO_TYPE_INT;
764 		struct gpio_desc *desc;
765 		u16 pin_index;
766 
767 		if (lookup->info.quirks & ACPI_GPIO_QUIRK_ONLY_GPIOIO && gpioint)
768 			lookup->index++;
769 
770 		if (lookup->n++ != lookup->index)
771 			return 1;
772 
773 		pin_index = lookup->pin_index;
774 		if (pin_index >= agpio->pin_table_length)
775 			return 1;
776 
777 		if (lookup->info.quirks & ACPI_GPIO_QUIRK_ABSOLUTE_NUMBER)
778 			desc = gpio_to_desc(agpio->pin_table[pin_index]);
779 		else
780 			desc = acpi_get_gpiod(agpio->resource_source.string_ptr,
781 					      agpio->pin_table[pin_index]);
782 		lookup->desc = desc;
783 		lookup->info.pin_config = agpio->pin_config;
784 		lookup->info.debounce = agpio->debounce_timeout;
785 		lookup->info.gpioint = gpioint;
786 		lookup->info.wake_capable = acpi_gpio_irq_is_wake(&lookup->info.adev->dev, agpio);
787 
788 		/*
789 		 * Polarity and triggering are only specified for GpioInt
790 		 * resource.
791 		 * Note: we expect here:
792 		 * - ACPI_ACTIVE_LOW == GPIO_ACTIVE_LOW
793 		 * - ACPI_ACTIVE_HIGH == GPIO_ACTIVE_HIGH
794 		 */
795 		if (lookup->info.gpioint) {
796 			lookup->info.polarity = agpio->polarity;
797 			lookup->info.triggering = agpio->triggering;
798 		} else {
799 			lookup->info.polarity = lookup->active_low;
800 		}
801 
802 		lookup->info.flags = acpi_gpio_to_gpiod_flags(agpio, lookup->info.polarity);
803 	}
804 
805 	return 1;
806 }
807 
808 static int acpi_gpio_resource_lookup(struct acpi_gpio_lookup *lookup,
809 				     struct acpi_gpio_info *info)
810 {
811 	struct acpi_device *adev = lookup->info.adev;
812 	struct list_head res_list;
813 	int ret;
814 
815 	INIT_LIST_HEAD(&res_list);
816 
817 	ret = acpi_dev_get_resources(adev, &res_list,
818 				     acpi_populate_gpio_lookup,
819 				     lookup);
820 	if (ret < 0)
821 		return ret;
822 
823 	acpi_dev_free_resource_list(&res_list);
824 
825 	if (!lookup->desc)
826 		return -ENOENT;
827 
828 	if (info)
829 		*info = lookup->info;
830 	return 0;
831 }
832 
833 static int acpi_gpio_property_lookup(struct fwnode_handle *fwnode,
834 				     const char *propname, int index,
835 				     struct acpi_gpio_lookup *lookup)
836 {
837 	struct fwnode_reference_args args;
838 	unsigned int quirks = 0;
839 	int ret;
840 
841 	memset(&args, 0, sizeof(args));
842 	ret = __acpi_node_get_property_reference(fwnode, propname, index, 3,
843 						 &args);
844 	if (ret) {
845 		struct acpi_device *adev;
846 
847 		adev = to_acpi_device_node(fwnode);
848 		if (!acpi_get_driver_gpio_data(adev, propname, index, &args, &quirks))
849 			return ret;
850 	}
851 	/*
852 	 * The property was found and resolved, so need to lookup the GPIO based
853 	 * on returned args.
854 	 */
855 	if (!to_acpi_device_node(args.fwnode))
856 		return -EINVAL;
857 	if (args.nargs != 3)
858 		return -EPROTO;
859 
860 	lookup->index = args.args[0];
861 	lookup->pin_index = args.args[1];
862 	lookup->active_low = !!args.args[2];
863 
864 	lookup->info.adev = to_acpi_device_node(args.fwnode);
865 	lookup->info.quirks = quirks;
866 
867 	return 0;
868 }
869 
870 /**
871  * acpi_get_gpiod_by_index() - get a GPIO descriptor from device resources
872  * @adev: pointer to a ACPI device to get GPIO from
873  * @propname: Property name of the GPIO (optional)
874  * @index: index of GpioIo/GpioInt resource (starting from %0)
875  * @info: info pointer to fill in (optional)
876  *
877  * Function goes through ACPI resources for @adev and based on @index looks
878  * up a GpioIo/GpioInt resource, translates it to the Linux GPIO descriptor,
879  * and returns it. @index matches GpioIo/GpioInt resources only so if there
880  * are total %3 GPIO resources, the index goes from %0 to %2.
881  *
882  * If @propname is specified the GPIO is looked using device property. In
883  * that case @index is used to select the GPIO entry in the property value
884  * (in case of multiple).
885  *
886  * If the GPIO cannot be translated or there is an error, an ERR_PTR is
887  * returned.
888  *
889  * Note: if the GPIO resource has multiple entries in the pin list, this
890  * function only returns the first.
891  */
892 static struct gpio_desc *acpi_get_gpiod_by_index(struct acpi_device *adev,
893 						 const char *propname,
894 						 int index,
895 						 struct acpi_gpio_info *info)
896 {
897 	struct acpi_gpio_lookup lookup;
898 	int ret;
899 
900 	if (!adev)
901 		return ERR_PTR(-ENODEV);
902 
903 	memset(&lookup, 0, sizeof(lookup));
904 	lookup.index = index;
905 
906 	if (propname) {
907 		dev_dbg(&adev->dev, "GPIO: looking up %s\n", propname);
908 
909 		ret = acpi_gpio_property_lookup(acpi_fwnode_handle(adev),
910 						propname, index, &lookup);
911 		if (ret)
912 			return ERR_PTR(ret);
913 
914 		dev_dbg(&adev->dev, "GPIO: _DSD returned %s %d %u %u\n",
915 			dev_name(&lookup.info.adev->dev), lookup.index,
916 			lookup.pin_index, lookup.active_low);
917 	} else {
918 		dev_dbg(&adev->dev, "GPIO: looking up %d in _CRS\n", index);
919 		lookup.info.adev = adev;
920 	}
921 
922 	ret = acpi_gpio_resource_lookup(&lookup, info);
923 	return ret ? ERR_PTR(ret) : lookup.desc;
924 }
925 
926 /**
927  * acpi_get_gpiod_from_data() - get a GPIO descriptor from ACPI data node
928  * @fwnode: pointer to an ACPI firmware node to get the GPIO information from
929  * @propname: Property name of the GPIO
930  * @index: index of GpioIo/GpioInt resource (starting from %0)
931  * @info: info pointer to fill in (optional)
932  *
933  * This function uses the property-based GPIO lookup to get to the GPIO
934  * resource with the relevant information from a data-only ACPI firmware node
935  * and uses that to obtain the GPIO descriptor to return.
936  *
937  * If the GPIO cannot be translated or there is an error an ERR_PTR is
938  * returned.
939  */
940 static struct gpio_desc *acpi_get_gpiod_from_data(struct fwnode_handle *fwnode,
941 						  const char *propname,
942 						  int index,
943 						  struct acpi_gpio_info *info)
944 {
945 	struct acpi_gpio_lookup lookup;
946 	int ret;
947 
948 	if (!is_acpi_data_node(fwnode))
949 		return ERR_PTR(-ENODEV);
950 
951 	if (!propname)
952 		return ERR_PTR(-EINVAL);
953 
954 	memset(&lookup, 0, sizeof(lookup));
955 	lookup.index = index;
956 
957 	ret = acpi_gpio_property_lookup(fwnode, propname, index, &lookup);
958 	if (ret)
959 		return ERR_PTR(ret);
960 
961 	ret = acpi_gpio_resource_lookup(&lookup, info);
962 	return ret ? ERR_PTR(ret) : lookup.desc;
963 }
964 
965 static bool acpi_can_fallback_to_crs(struct acpi_device *adev,
966 				     const char *con_id)
967 {
968 	/* Never allow fallback if the device has properties */
969 	if (acpi_dev_has_props(adev) || adev->driver_gpios)
970 		return false;
971 
972 	return con_id == NULL;
973 }
974 
975 struct gpio_desc *acpi_find_gpio(struct fwnode_handle *fwnode,
976 				 const char *con_id,
977 				 unsigned int idx,
978 				 enum gpiod_flags *dflags,
979 				 unsigned long *lookupflags)
980 {
981 	struct acpi_device *adev = to_acpi_device_node(fwnode);
982 	struct acpi_gpio_info info;
983 	struct gpio_desc *desc;
984 	char propname[32];
985 	int i;
986 
987 	/* Try first from _DSD */
988 	for (i = 0; i < ARRAY_SIZE(gpio_suffixes); i++) {
989 		if (con_id) {
990 			snprintf(propname, sizeof(propname), "%s-%s",
991 				 con_id, gpio_suffixes[i]);
992 		} else {
993 			snprintf(propname, sizeof(propname), "%s",
994 				 gpio_suffixes[i]);
995 		}
996 
997 		if (adev)
998 			desc = acpi_get_gpiod_by_index(adev,
999 						       propname, idx, &info);
1000 		else
1001 			desc = acpi_get_gpiod_from_data(fwnode,
1002 						        propname, idx, &info);
1003 		if (!IS_ERR(desc))
1004 			break;
1005 		if (PTR_ERR(desc) == -EPROBE_DEFER)
1006 			return ERR_CAST(desc);
1007 	}
1008 
1009 	/* Then from plain _CRS GPIOs */
1010 	if (IS_ERR(desc)) {
1011 		if (!adev || !acpi_can_fallback_to_crs(adev, con_id))
1012 			return ERR_PTR(-ENOENT);
1013 
1014 		desc = acpi_get_gpiod_by_index(adev, NULL, idx, &info);
1015 		if (IS_ERR(desc))
1016 			return desc;
1017 	}
1018 
1019 	if (info.gpioint &&
1020 	    (*dflags == GPIOD_OUT_LOW || *dflags == GPIOD_OUT_HIGH)) {
1021 		dev_dbg(&adev->dev, "refusing GpioInt() entry when doing GPIOD_OUT_* lookup\n");
1022 		return ERR_PTR(-ENOENT);
1023 	}
1024 
1025 	acpi_gpio_update_gpiod_flags(dflags, &info);
1026 	acpi_gpio_update_gpiod_lookup_flags(lookupflags, &info);
1027 	return desc;
1028 }
1029 
1030 /**
1031  * acpi_dev_gpio_irq_wake_get_by() - Find GpioInt and translate it to Linux IRQ number
1032  * @adev: pointer to a ACPI device to get IRQ from
1033  * @name: optional name of GpioInt resource
1034  * @index: index of GpioInt resource (starting from %0)
1035  * @wake_capable: Set to true if the IRQ is wake capable
1036  *
1037  * If the device has one or more GpioInt resources, this function can be
1038  * used to translate from the GPIO offset in the resource to the Linux IRQ
1039  * number.
1040  *
1041  * The function is idempotent, though each time it runs it will configure GPIO
1042  * pin direction according to the flags in GpioInt resource.
1043  *
1044  * The function takes optional @name parameter. If the resource has a property
1045  * name, then only those will be taken into account.
1046  *
1047  * The GPIO is considered wake capable if the GpioInt resource specifies
1048  * SharedAndWake or ExclusiveAndWake.
1049  *
1050  * Return: Linux IRQ number (> %0) on success, negative errno on failure.
1051  */
1052 int acpi_dev_gpio_irq_wake_get_by(struct acpi_device *adev, const char *name, int index,
1053 				  bool *wake_capable)
1054 {
1055 	int idx, i;
1056 	unsigned int irq_flags;
1057 	int ret;
1058 
1059 	for (i = 0, idx = 0; idx <= index; i++) {
1060 		struct acpi_gpio_info info;
1061 		struct gpio_desc *desc;
1062 
1063 		desc = acpi_get_gpiod_by_index(adev, name, i, &info);
1064 
1065 		/* Ignore -EPROBE_DEFER, it only matters if idx matches */
1066 		if (IS_ERR(desc) && PTR_ERR(desc) != -EPROBE_DEFER)
1067 			return PTR_ERR(desc);
1068 
1069 		if (info.gpioint && idx++ == index) {
1070 			unsigned long lflags = GPIO_LOOKUP_FLAGS_DEFAULT;
1071 			enum gpiod_flags dflags = GPIOD_ASIS;
1072 			char label[32];
1073 			int irq;
1074 
1075 			if (IS_ERR(desc))
1076 				return PTR_ERR(desc);
1077 
1078 			irq = gpiod_to_irq(desc);
1079 			if (irq < 0)
1080 				return irq;
1081 
1082 			acpi_gpio_update_gpiod_flags(&dflags, &info);
1083 			acpi_gpio_update_gpiod_lookup_flags(&lflags, &info);
1084 
1085 			snprintf(label, sizeof(label), "GpioInt() %d", index);
1086 			ret = gpiod_configure_flags(desc, label, lflags, dflags);
1087 			if (ret < 0)
1088 				return ret;
1089 
1090 			/* ACPI uses hundredths of milliseconds units */
1091 			ret = gpio_set_debounce_timeout(desc, info.debounce * 10);
1092 			if (ret)
1093 				return ret;
1094 
1095 			irq_flags = acpi_dev_get_irq_type(info.triggering,
1096 							  info.polarity);
1097 
1098 			/*
1099 			 * If the IRQ is not already in use then set type
1100 			 * if specified and different than the current one.
1101 			 */
1102 			if (can_request_irq(irq, irq_flags)) {
1103 				if (irq_flags != IRQ_TYPE_NONE &&
1104 				    irq_flags != irq_get_trigger_type(irq))
1105 					irq_set_irq_type(irq, irq_flags);
1106 			} else {
1107 				dev_dbg(&adev->dev, "IRQ %d already in use\n", irq);
1108 			}
1109 
1110 			/* avoid suspend issues with GPIOs when systems are using S3 */
1111 			if (wake_capable && acpi_gbl_FADT.flags & ACPI_FADT_LOW_POWER_S0)
1112 				*wake_capable = info.wake_capable;
1113 
1114 			return irq;
1115 		}
1116 
1117 	}
1118 	return -ENOENT;
1119 }
1120 EXPORT_SYMBOL_GPL(acpi_dev_gpio_irq_wake_get_by);
1121 
1122 static acpi_status
1123 acpi_gpio_adr_space_handler(u32 function, acpi_physical_address address,
1124 			    u32 bits, u64 *value, void *handler_context,
1125 			    void *region_context)
1126 {
1127 	struct acpi_gpio_chip *achip = region_context;
1128 	struct gpio_chip *chip = achip->chip;
1129 	struct acpi_resource_gpio *agpio;
1130 	struct acpi_resource *ares;
1131 	u16 pin_index = address;
1132 	acpi_status status;
1133 	int length;
1134 	int i;
1135 
1136 	status = acpi_buffer_to_resource(achip->conn_info.connection,
1137 					 achip->conn_info.length, &ares);
1138 	if (ACPI_FAILURE(status))
1139 		return status;
1140 
1141 	if (WARN_ON(ares->type != ACPI_RESOURCE_TYPE_GPIO)) {
1142 		ACPI_FREE(ares);
1143 		return AE_BAD_PARAMETER;
1144 	}
1145 
1146 	agpio = &ares->data.gpio;
1147 
1148 	if (WARN_ON(agpio->io_restriction == ACPI_IO_RESTRICT_INPUT &&
1149 	    function == ACPI_WRITE)) {
1150 		ACPI_FREE(ares);
1151 		return AE_BAD_PARAMETER;
1152 	}
1153 
1154 	length = min_t(u16, agpio->pin_table_length, pin_index + bits);
1155 	for (i = pin_index; i < length; ++i) {
1156 		unsigned int pin = agpio->pin_table[i];
1157 		struct acpi_gpio_connection *conn;
1158 		struct gpio_desc *desc;
1159 		bool found;
1160 
1161 		mutex_lock(&achip->conn_lock);
1162 
1163 		found = false;
1164 		list_for_each_entry(conn, &achip->conns, node) {
1165 			if (conn->pin == pin) {
1166 				found = true;
1167 				desc = conn->desc;
1168 				break;
1169 			}
1170 		}
1171 
1172 		/*
1173 		 * The same GPIO can be shared between operation region and
1174 		 * event but only if the access here is ACPI_READ. In that
1175 		 * case we "borrow" the event GPIO instead.
1176 		 */
1177 		if (!found && agpio->shareable == ACPI_SHARED &&
1178 		     function == ACPI_READ) {
1179 			struct acpi_gpio_event *event;
1180 
1181 			list_for_each_entry(event, &achip->events, node) {
1182 				if (event->pin == pin) {
1183 					desc = event->desc;
1184 					found = true;
1185 					break;
1186 				}
1187 			}
1188 		}
1189 
1190 		if (!found) {
1191 			desc = acpi_request_own_gpiod(chip, agpio, i, "ACPI:OpRegion");
1192 			if (IS_ERR(desc)) {
1193 				mutex_unlock(&achip->conn_lock);
1194 				status = AE_ERROR;
1195 				goto out;
1196 			}
1197 
1198 			conn = kzalloc(sizeof(*conn), GFP_KERNEL);
1199 			if (!conn) {
1200 				gpiochip_free_own_desc(desc);
1201 				mutex_unlock(&achip->conn_lock);
1202 				status = AE_NO_MEMORY;
1203 				goto out;
1204 			}
1205 
1206 			conn->pin = pin;
1207 			conn->desc = desc;
1208 			list_add_tail(&conn->node, &achip->conns);
1209 		}
1210 
1211 		mutex_unlock(&achip->conn_lock);
1212 
1213 		if (function == ACPI_WRITE)
1214 			gpiod_set_raw_value_cansleep(desc, !!(*value & BIT(i)));
1215 		else
1216 			*value |= (u64)gpiod_get_raw_value_cansleep(desc) << i;
1217 	}
1218 
1219 out:
1220 	ACPI_FREE(ares);
1221 	return status;
1222 }
1223 
1224 static void acpi_gpiochip_request_regions(struct acpi_gpio_chip *achip)
1225 {
1226 	struct gpio_chip *chip = achip->chip;
1227 	acpi_handle handle = ACPI_HANDLE(chip->parent);
1228 	acpi_status status;
1229 
1230 	INIT_LIST_HEAD(&achip->conns);
1231 	mutex_init(&achip->conn_lock);
1232 	status = acpi_install_address_space_handler(handle, ACPI_ADR_SPACE_GPIO,
1233 						    acpi_gpio_adr_space_handler,
1234 						    NULL, achip);
1235 	if (ACPI_FAILURE(status))
1236 		dev_err(chip->parent,
1237 		        "Failed to install GPIO OpRegion handler\n");
1238 }
1239 
1240 static void acpi_gpiochip_free_regions(struct acpi_gpio_chip *achip)
1241 {
1242 	struct gpio_chip *chip = achip->chip;
1243 	acpi_handle handle = ACPI_HANDLE(chip->parent);
1244 	struct acpi_gpio_connection *conn, *tmp;
1245 	acpi_status status;
1246 
1247 	status = acpi_remove_address_space_handler(handle, ACPI_ADR_SPACE_GPIO,
1248 						   acpi_gpio_adr_space_handler);
1249 	if (ACPI_FAILURE(status)) {
1250 		dev_err(chip->parent,
1251 			"Failed to remove GPIO OpRegion handler\n");
1252 		return;
1253 	}
1254 
1255 	list_for_each_entry_safe_reverse(conn, tmp, &achip->conns, node) {
1256 		gpiochip_free_own_desc(conn->desc);
1257 		list_del(&conn->node);
1258 		kfree(conn);
1259 	}
1260 }
1261 
1262 static struct gpio_desc *
1263 acpi_gpiochip_parse_own_gpio(struct acpi_gpio_chip *achip,
1264 			     struct fwnode_handle *fwnode,
1265 			     const char **name,
1266 			     unsigned long *lflags,
1267 			     enum gpiod_flags *dflags)
1268 {
1269 	struct gpio_chip *chip = achip->chip;
1270 	struct gpio_desc *desc;
1271 	u32 gpios[2];
1272 	int ret;
1273 
1274 	*lflags = GPIO_LOOKUP_FLAGS_DEFAULT;
1275 	*dflags = GPIOD_ASIS;
1276 	*name = NULL;
1277 
1278 	ret = fwnode_property_read_u32_array(fwnode, "gpios", gpios,
1279 					     ARRAY_SIZE(gpios));
1280 	if (ret < 0)
1281 		return ERR_PTR(ret);
1282 
1283 	desc = gpiochip_get_desc(chip, gpios[0]);
1284 	if (IS_ERR(desc))
1285 		return desc;
1286 
1287 	if (gpios[1])
1288 		*lflags |= GPIO_ACTIVE_LOW;
1289 
1290 	if (fwnode_property_present(fwnode, "input"))
1291 		*dflags |= GPIOD_IN;
1292 	else if (fwnode_property_present(fwnode, "output-low"))
1293 		*dflags |= GPIOD_OUT_LOW;
1294 	else if (fwnode_property_present(fwnode, "output-high"))
1295 		*dflags |= GPIOD_OUT_HIGH;
1296 	else
1297 		return ERR_PTR(-EINVAL);
1298 
1299 	fwnode_property_read_string(fwnode, "line-name", name);
1300 
1301 	return desc;
1302 }
1303 
1304 static void acpi_gpiochip_scan_gpios(struct acpi_gpio_chip *achip)
1305 {
1306 	struct gpio_chip *chip = achip->chip;
1307 	struct fwnode_handle *fwnode;
1308 
1309 	device_for_each_child_node(chip->parent, fwnode) {
1310 		unsigned long lflags;
1311 		enum gpiod_flags dflags;
1312 		struct gpio_desc *desc;
1313 		const char *name;
1314 		int ret;
1315 
1316 		if (!fwnode_property_present(fwnode, "gpio-hog"))
1317 			continue;
1318 
1319 		desc = acpi_gpiochip_parse_own_gpio(achip, fwnode, &name,
1320 						    &lflags, &dflags);
1321 		if (IS_ERR(desc))
1322 			continue;
1323 
1324 		ret = gpiod_hog(desc, name, lflags, dflags);
1325 		if (ret) {
1326 			dev_err(chip->parent, "Failed to hog GPIO\n");
1327 			fwnode_handle_put(fwnode);
1328 			return;
1329 		}
1330 	}
1331 }
1332 
1333 void acpi_gpiochip_add(struct gpio_chip *chip)
1334 {
1335 	struct acpi_gpio_chip *acpi_gpio;
1336 	struct acpi_device *adev;
1337 	acpi_status status;
1338 
1339 	if (!chip || !chip->parent)
1340 		return;
1341 
1342 	adev = ACPI_COMPANION(chip->parent);
1343 	if (!adev)
1344 		return;
1345 
1346 	acpi_gpio = kzalloc(sizeof(*acpi_gpio), GFP_KERNEL);
1347 	if (!acpi_gpio) {
1348 		dev_err(chip->parent,
1349 			"Failed to allocate memory for ACPI GPIO chip\n");
1350 		return;
1351 	}
1352 
1353 	acpi_gpio->chip = chip;
1354 	INIT_LIST_HEAD(&acpi_gpio->events);
1355 	INIT_LIST_HEAD(&acpi_gpio->deferred_req_irqs_list_entry);
1356 
1357 	status = acpi_attach_data(adev->handle, acpi_gpio_chip_dh, acpi_gpio);
1358 	if (ACPI_FAILURE(status)) {
1359 		dev_err(chip->parent, "Failed to attach ACPI GPIO chip\n");
1360 		kfree(acpi_gpio);
1361 		return;
1362 	}
1363 
1364 	acpi_gpiochip_request_regions(acpi_gpio);
1365 	acpi_gpiochip_scan_gpios(acpi_gpio);
1366 	acpi_dev_clear_dependencies(adev);
1367 }
1368 
1369 void acpi_gpiochip_remove(struct gpio_chip *chip)
1370 {
1371 	struct acpi_gpio_chip *acpi_gpio;
1372 	acpi_handle handle;
1373 	acpi_status status;
1374 
1375 	if (!chip || !chip->parent)
1376 		return;
1377 
1378 	handle = ACPI_HANDLE(chip->parent);
1379 	if (!handle)
1380 		return;
1381 
1382 	status = acpi_get_data(handle, acpi_gpio_chip_dh, (void **)&acpi_gpio);
1383 	if (ACPI_FAILURE(status)) {
1384 		dev_warn(chip->parent, "Failed to retrieve ACPI GPIO chip\n");
1385 		return;
1386 	}
1387 
1388 	acpi_gpiochip_free_regions(acpi_gpio);
1389 
1390 	acpi_detach_data(handle, acpi_gpio_chip_dh);
1391 	kfree(acpi_gpio);
1392 }
1393 
1394 static int acpi_gpio_package_count(const union acpi_object *obj)
1395 {
1396 	const union acpi_object *element = obj->package.elements;
1397 	const union acpi_object *end = element + obj->package.count;
1398 	unsigned int count = 0;
1399 
1400 	while (element < end) {
1401 		switch (element->type) {
1402 		case ACPI_TYPE_LOCAL_REFERENCE:
1403 			element += 3;
1404 			fallthrough;
1405 		case ACPI_TYPE_INTEGER:
1406 			element++;
1407 			count++;
1408 			break;
1409 
1410 		default:
1411 			return -EPROTO;
1412 		}
1413 	}
1414 
1415 	return count;
1416 }
1417 
1418 static int acpi_find_gpio_count(struct acpi_resource *ares, void *data)
1419 {
1420 	unsigned int *count = data;
1421 
1422 	if (ares->type == ACPI_RESOURCE_TYPE_GPIO)
1423 		*count += ares->data.gpio.pin_table_length;
1424 
1425 	return 1;
1426 }
1427 
1428 /**
1429  * acpi_gpio_count - count the GPIOs associated with a device / function
1430  * @dev:	GPIO consumer, can be %NULL for system-global GPIOs
1431  * @con_id:	function within the GPIO consumer
1432  *
1433  * Return:
1434  * The number of GPIOs associated with a device / function or %-ENOENT,
1435  * if no GPIO has been assigned to the requested function.
1436  */
1437 int acpi_gpio_count(struct device *dev, const char *con_id)
1438 {
1439 	struct acpi_device *adev = ACPI_COMPANION(dev);
1440 	const union acpi_object *obj;
1441 	const struct acpi_gpio_mapping *gm;
1442 	int count = -ENOENT;
1443 	int ret;
1444 	char propname[32];
1445 	unsigned int i;
1446 
1447 	/* Try first from _DSD */
1448 	for (i = 0; i < ARRAY_SIZE(gpio_suffixes); i++) {
1449 		if (con_id)
1450 			snprintf(propname, sizeof(propname), "%s-%s",
1451 				 con_id, gpio_suffixes[i]);
1452 		else
1453 			snprintf(propname, sizeof(propname), "%s",
1454 				 gpio_suffixes[i]);
1455 
1456 		ret = acpi_dev_get_property(adev, propname, ACPI_TYPE_ANY,
1457 					    &obj);
1458 		if (ret == 0) {
1459 			if (obj->type == ACPI_TYPE_LOCAL_REFERENCE)
1460 				count = 1;
1461 			else if (obj->type == ACPI_TYPE_PACKAGE)
1462 				count = acpi_gpio_package_count(obj);
1463 		} else if (adev->driver_gpios) {
1464 			for (gm = adev->driver_gpios; gm->name; gm++)
1465 				if (strcmp(propname, gm->name) == 0) {
1466 					count = gm->size;
1467 					break;
1468 				}
1469 		}
1470 		if (count > 0)
1471 			break;
1472 	}
1473 
1474 	/* Then from plain _CRS GPIOs */
1475 	if (count < 0) {
1476 		struct list_head resource_list;
1477 		unsigned int crs_count = 0;
1478 
1479 		if (!acpi_can_fallback_to_crs(adev, con_id))
1480 			return count;
1481 
1482 		INIT_LIST_HEAD(&resource_list);
1483 		acpi_dev_get_resources(adev, &resource_list,
1484 				       acpi_find_gpio_count, &crs_count);
1485 		acpi_dev_free_resource_list(&resource_list);
1486 		if (crs_count > 0)
1487 			count = crs_count;
1488 	}
1489 	return count ? count : -ENOENT;
1490 }
1491 
1492 /* Run deferred acpi_gpiochip_request_irqs() */
1493 static int __init acpi_gpio_handle_deferred_request_irqs(void)
1494 {
1495 	struct acpi_gpio_chip *acpi_gpio, *tmp;
1496 
1497 	mutex_lock(&acpi_gpio_deferred_req_irqs_lock);
1498 	list_for_each_entry_safe(acpi_gpio, tmp,
1499 				 &acpi_gpio_deferred_req_irqs_list,
1500 				 deferred_req_irqs_list_entry)
1501 		acpi_gpiochip_request_irqs(acpi_gpio);
1502 
1503 	acpi_gpio_deferred_req_irqs_done = true;
1504 	mutex_unlock(&acpi_gpio_deferred_req_irqs_lock);
1505 
1506 	return 0;
1507 }
1508 /* We must use _sync so that this runs after the first deferred_probe run */
1509 late_initcall_sync(acpi_gpio_handle_deferred_request_irqs);
1510 
1511 static const struct dmi_system_id gpiolib_acpi_quirks[] __initconst = {
1512 	{
1513 		/*
1514 		 * The Minix Neo Z83-4 has a micro-USB-B id-pin handler for
1515 		 * a non existing micro-USB-B connector which puts the HDMI
1516 		 * DDC pins in GPIO mode, breaking HDMI support.
1517 		 */
1518 		.matches = {
1519 			DMI_MATCH(DMI_SYS_VENDOR, "MINIX"),
1520 			DMI_MATCH(DMI_PRODUCT_NAME, "Z83-4"),
1521 		},
1522 		.driver_data = &(struct acpi_gpiolib_dmi_quirk) {
1523 			.no_edge_events_on_boot = true,
1524 		},
1525 	},
1526 	{
1527 		/*
1528 		 * The Terra Pad 1061 has a micro-USB-B id-pin handler, which
1529 		 * instead of controlling the actual micro-USB-B turns the 5V
1530 		 * boost for its USB-A connector off. The actual micro-USB-B
1531 		 * connector is wired for charging only.
1532 		 */
1533 		.matches = {
1534 			DMI_MATCH(DMI_SYS_VENDOR, "Wortmann_AG"),
1535 			DMI_MATCH(DMI_PRODUCT_NAME, "TERRA_PAD_1061"),
1536 		},
1537 		.driver_data = &(struct acpi_gpiolib_dmi_quirk) {
1538 			.no_edge_events_on_boot = true,
1539 		},
1540 	},
1541 	{
1542 		/*
1543 		 * The Dell Venue 10 Pro 5055, with Bay Trail SoC + TI PMIC uses an
1544 		 * external embedded-controller connected via I2C + an ACPI GPIO
1545 		 * event handler on INT33FFC:02 pin 12, causing spurious wakeups.
1546 		 */
1547 		.matches = {
1548 			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
1549 			DMI_MATCH(DMI_PRODUCT_NAME, "Venue 10 Pro 5055"),
1550 		},
1551 		.driver_data = &(struct acpi_gpiolib_dmi_quirk) {
1552 			.ignore_wake = "INT33FC:02@12",
1553 		},
1554 	},
1555 	{
1556 		/*
1557 		 * HP X2 10 models with Cherry Trail SoC + TI PMIC use an
1558 		 * external embedded-controller connected via I2C + an ACPI GPIO
1559 		 * event handler on INT33FF:01 pin 0, causing spurious wakeups.
1560 		 * When suspending by closing the LID, the power to the USB
1561 		 * keyboard is turned off, causing INT0002 ACPI events to
1562 		 * trigger once the XHCI controller notices the keyboard is
1563 		 * gone. So INT0002 events cause spurious wakeups too. Ignoring
1564 		 * EC wakes breaks wakeup when opening the lid, the user needs
1565 		 * to press the power-button to wakeup the system. The
1566 		 * alternative is suspend simply not working, which is worse.
1567 		 */
1568 		.matches = {
1569 			DMI_MATCH(DMI_SYS_VENDOR, "HP"),
1570 			DMI_MATCH(DMI_PRODUCT_NAME, "HP x2 Detachable 10-p0XX"),
1571 		},
1572 		.driver_data = &(struct acpi_gpiolib_dmi_quirk) {
1573 			.ignore_wake = "INT33FF:01@0,INT0002:00@2",
1574 		},
1575 	},
1576 	{
1577 		/*
1578 		 * HP X2 10 models with Bay Trail SoC + AXP288 PMIC use an
1579 		 * external embedded-controller connected via I2C + an ACPI GPIO
1580 		 * event handler on INT33FC:02 pin 28, causing spurious wakeups.
1581 		 */
1582 		.matches = {
1583 			DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
1584 			DMI_MATCH(DMI_PRODUCT_NAME, "HP Pavilion x2 Detachable"),
1585 			DMI_MATCH(DMI_BOARD_NAME, "815D"),
1586 		},
1587 		.driver_data = &(struct acpi_gpiolib_dmi_quirk) {
1588 			.ignore_wake = "INT33FC:02@28",
1589 		},
1590 	},
1591 	{
1592 		/*
1593 		 * HP X2 10 models with Cherry Trail SoC + AXP288 PMIC use an
1594 		 * external embedded-controller connected via I2C + an ACPI GPIO
1595 		 * event handler on INT33FF:01 pin 0, causing spurious wakeups.
1596 		 */
1597 		.matches = {
1598 			DMI_MATCH(DMI_SYS_VENDOR, "HP"),
1599 			DMI_MATCH(DMI_PRODUCT_NAME, "HP Pavilion x2 Detachable"),
1600 			DMI_MATCH(DMI_BOARD_NAME, "813E"),
1601 		},
1602 		.driver_data = &(struct acpi_gpiolib_dmi_quirk) {
1603 			.ignore_wake = "INT33FF:01@0",
1604 		},
1605 	},
1606 	{
1607 		/*
1608 		 * Interrupt storm caused from edge triggered floating pin
1609 		 * Found in BIOS UX325UAZ.300
1610 		 * https://bugzilla.kernel.org/show_bug.cgi?id=216208
1611 		 */
1612 		.matches = {
1613 			DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK COMPUTER INC."),
1614 			DMI_MATCH(DMI_PRODUCT_NAME, "ZenBook UX325UAZ_UM325UAZ"),
1615 		},
1616 		.driver_data = &(struct acpi_gpiolib_dmi_quirk) {
1617 			.ignore_interrupt = "AMDI0030:00@18",
1618 		},
1619 	},
1620 	{
1621 		/*
1622 		 * Spurious wakeups from TP_ATTN# pin
1623 		 * Found in BIOS 1.7.8
1624 		 * https://gitlab.freedesktop.org/drm/amd/-/issues/1722#note_1720627
1625 		 */
1626 		.matches = {
1627 			DMI_MATCH(DMI_BOARD_NAME, "NL5xNU"),
1628 		},
1629 		.driver_data = &(struct acpi_gpiolib_dmi_quirk) {
1630 			.ignore_wake = "ELAN0415:00@9",
1631 		},
1632 	},
1633 	{
1634 		/*
1635 		 * Spurious wakeups from TP_ATTN# pin
1636 		 * Found in BIOS 1.7.8
1637 		 * https://gitlab.freedesktop.org/drm/amd/-/issues/1722#note_1720627
1638 		 */
1639 		.matches = {
1640 			DMI_MATCH(DMI_BOARD_NAME, "NL5xRU"),
1641 		},
1642 		.driver_data = &(struct acpi_gpiolib_dmi_quirk) {
1643 			.ignore_wake = "ELAN0415:00@9",
1644 		},
1645 	},
1646 	{
1647 		/*
1648 		 * Spurious wakeups from TP_ATTN# pin
1649 		 * Found in BIOS 1.7.7
1650 		 */
1651 		.matches = {
1652 			DMI_MATCH(DMI_BOARD_NAME, "NH5xAx"),
1653 		},
1654 		.driver_data = &(struct acpi_gpiolib_dmi_quirk) {
1655 			.ignore_wake = "SYNA1202:00@16",
1656 		},
1657 	},
1658 	{
1659 		/*
1660 		 * On the Peaq C1010 2-in-1 INT33FC:00 pin 3 is connected to
1661 		 * a "dolby" button. At the ACPI level an _AEI event-handler
1662 		 * is connected which sets an ACPI variable to 1 on both
1663 		 * edges. This variable can be polled + cleared to 0 using
1664 		 * WMI. But since the variable is set on both edges the WMI
1665 		 * interface is pretty useless even when polling.
1666 		 * So instead the x86-android-tablets code instantiates
1667 		 * a gpio-keys platform device for it.
1668 		 * Ignore the _AEI handler for the pin, so that it is not busy.
1669 		 */
1670 		.matches = {
1671 			DMI_MATCH(DMI_SYS_VENDOR, "PEAQ"),
1672 			DMI_MATCH(DMI_PRODUCT_NAME, "PEAQ PMM C1010 MD99187"),
1673 		},
1674 		.driver_data = &(struct acpi_gpiolib_dmi_quirk) {
1675 			.ignore_interrupt = "INT33FC:00@3",
1676 		},
1677 	},
1678 	{} /* Terminating entry */
1679 };
1680 
1681 static int __init acpi_gpio_setup_params(void)
1682 {
1683 	const struct acpi_gpiolib_dmi_quirk *quirk = NULL;
1684 	const struct dmi_system_id *id;
1685 
1686 	id = dmi_first_match(gpiolib_acpi_quirks);
1687 	if (id)
1688 		quirk = id->driver_data;
1689 
1690 	if (run_edge_events_on_boot < 0) {
1691 		if (quirk && quirk->no_edge_events_on_boot)
1692 			run_edge_events_on_boot = 0;
1693 		else
1694 			run_edge_events_on_boot = 1;
1695 	}
1696 
1697 	if (ignore_wake == NULL && quirk && quirk->ignore_wake)
1698 		ignore_wake = quirk->ignore_wake;
1699 
1700 	if (ignore_interrupt == NULL && quirk && quirk->ignore_interrupt)
1701 		ignore_interrupt = quirk->ignore_interrupt;
1702 
1703 	return 0;
1704 }
1705 
1706 /* Directly after dmi_setup() which runs as core_initcall() */
1707 postcore_initcall(acpi_gpio_setup_params);
1708