xref: /linux/drivers/gpio/gpiolib-acpi.c (revision 906fd46a65383cd639e5eec72a047efc33045d86)
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, const void *data)
130 {
131 	/* First check the actual GPIO device */
132 	if (device_match_acpi_handle(&gc->gpiodev->dev, data))
133 		return true;
134 
135 	/*
136 	 * When the ACPI device is artificially split to the banks of GPIOs,
137 	 * where each of them is represented by a separate GPIO device,
138 	 * the firmware node of the physical device may not be shared among
139 	 * the banks as they may require different values for the same property,
140 	 * e.g., number of GPIOs in a certain bank. In such case the ACPI handle
141 	 * of a GPIO device is NULL and can not be used. Hence we have to check
142 	 * the parent device to be sure that there is no match before bailing
143 	 * out.
144 	 */
145 	if (gc->parent)
146 		return device_match_acpi_handle(gc->parent, data);
147 
148 	return false;
149 }
150 
151 /**
152  * acpi_get_gpiod() - Translate ACPI GPIO pin to GPIO descriptor usable with GPIO API
153  * @path:	ACPI GPIO controller full path name, (e.g. "\\_SB.GPO1")
154  * @pin:	ACPI GPIO pin number (0-based, controller-relative)
155  *
156  * Return: GPIO descriptor to use with Linux generic GPIO API, or ERR_PTR
157  * error value. Specifically returns %-EPROBE_DEFER if the referenced GPIO
158  * controller does not have GPIO chip registered at the moment. This is to
159  * support probe deferral.
160  */
161 static struct gpio_desc *acpi_get_gpiod(char *path, unsigned int pin)
162 {
163 	acpi_handle handle;
164 	acpi_status status;
165 
166 	status = acpi_get_handle(NULL, path, &handle);
167 	if (ACPI_FAILURE(status))
168 		return ERR_PTR(-ENODEV);
169 
170 	struct gpio_device *gdev __free(gpio_device_put) =
171 				gpio_device_find(handle, acpi_gpiochip_find);
172 	if (!gdev)
173 		return ERR_PTR(-EPROBE_DEFER);
174 
175 	/*
176 	 * FIXME: keep track of the reference to the GPIO device somehow
177 	 * instead of putting it here.
178 	 */
179 	return gpio_device_get_desc(gdev, pin);
180 }
181 
182 static irqreturn_t acpi_gpio_irq_handler(int irq, void *data)
183 {
184 	struct acpi_gpio_event *event = data;
185 
186 	acpi_evaluate_object(event->handle, NULL, NULL, NULL);
187 
188 	return IRQ_HANDLED;
189 }
190 
191 static irqreturn_t acpi_gpio_irq_handler_evt(int irq, void *data)
192 {
193 	struct acpi_gpio_event *event = data;
194 
195 	acpi_execute_simple_method(event->handle, NULL, event->pin);
196 
197 	return IRQ_HANDLED;
198 }
199 
200 static void acpi_gpio_chip_dh(acpi_handle handle, void *data)
201 {
202 	/* The address of this function is used as a key. */
203 }
204 
205 bool acpi_gpio_get_irq_resource(struct acpi_resource *ares,
206 				struct acpi_resource_gpio **agpio)
207 {
208 	struct acpi_resource_gpio *gpio;
209 
210 	if (ares->type != ACPI_RESOURCE_TYPE_GPIO)
211 		return false;
212 
213 	gpio = &ares->data.gpio;
214 	if (gpio->connection_type != ACPI_RESOURCE_GPIO_TYPE_INT)
215 		return false;
216 
217 	*agpio = gpio;
218 	return true;
219 }
220 EXPORT_SYMBOL_GPL(acpi_gpio_get_irq_resource);
221 
222 /**
223  * acpi_gpio_get_io_resource - Fetch details of an ACPI resource if it is a GPIO
224  *			       I/O resource or return False if not.
225  * @ares:	Pointer to the ACPI resource to fetch
226  * @agpio:	Pointer to a &struct acpi_resource_gpio to store the output pointer
227  */
228 bool acpi_gpio_get_io_resource(struct acpi_resource *ares,
229 			       struct acpi_resource_gpio **agpio)
230 {
231 	struct acpi_resource_gpio *gpio;
232 
233 	if (ares->type != ACPI_RESOURCE_TYPE_GPIO)
234 		return false;
235 
236 	gpio = &ares->data.gpio;
237 	if (gpio->connection_type != ACPI_RESOURCE_GPIO_TYPE_IO)
238 		return false;
239 
240 	*agpio = gpio;
241 	return true;
242 }
243 EXPORT_SYMBOL_GPL(acpi_gpio_get_io_resource);
244 
245 static void acpi_gpiochip_request_irq(struct acpi_gpio_chip *acpi_gpio,
246 				      struct acpi_gpio_event *event)
247 {
248 	struct device *parent = acpi_gpio->chip->parent;
249 	int ret, value;
250 
251 	ret = request_threaded_irq(event->irq, NULL, event->handler,
252 				   event->irqflags | IRQF_ONESHOT, "ACPI:Event", event);
253 	if (ret) {
254 		dev_err(parent, "Failed to setup interrupt handler for %d\n", event->irq);
255 		return;
256 	}
257 
258 	if (event->irq_is_wake)
259 		enable_irq_wake(event->irq);
260 
261 	event->irq_requested = true;
262 
263 	/* Make sure we trigger the initial state of edge-triggered IRQs */
264 	if (run_edge_events_on_boot &&
265 	    (event->irqflags & (IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING))) {
266 		value = gpiod_get_raw_value_cansleep(event->desc);
267 		if (((event->irqflags & IRQF_TRIGGER_RISING) && value == 1) ||
268 		    ((event->irqflags & IRQF_TRIGGER_FALLING) && value == 0))
269 			event->handler(event->irq, event);
270 	}
271 }
272 
273 static void acpi_gpiochip_request_irqs(struct acpi_gpio_chip *acpi_gpio)
274 {
275 	struct acpi_gpio_event *event;
276 
277 	list_for_each_entry(event, &acpi_gpio->events, node)
278 		acpi_gpiochip_request_irq(acpi_gpio, event);
279 }
280 
281 static enum gpiod_flags
282 acpi_gpio_to_gpiod_flags(const struct acpi_resource_gpio *agpio, int polarity)
283 {
284 	/* GpioInt() implies input configuration */
285 	if (agpio->connection_type == ACPI_RESOURCE_GPIO_TYPE_INT)
286 		return GPIOD_IN;
287 
288 	switch (agpio->io_restriction) {
289 	case ACPI_IO_RESTRICT_INPUT:
290 		return GPIOD_IN;
291 	case ACPI_IO_RESTRICT_OUTPUT:
292 		/*
293 		 * ACPI GPIO resources don't contain an initial value for the
294 		 * GPIO. Therefore we deduce that value from the pull field
295 		 * and the polarity instead. If the pin is pulled up we assume
296 		 * default to be high, if it is pulled down we assume default
297 		 * to be low, otherwise we leave pin untouched. For active low
298 		 * polarity values will be switched. See also
299 		 * Documentation/firmware-guide/acpi/gpio-properties.rst.
300 		 */
301 		switch (agpio->pin_config) {
302 		case ACPI_PIN_CONFIG_PULLUP:
303 			return polarity == GPIO_ACTIVE_LOW ? GPIOD_OUT_LOW : GPIOD_OUT_HIGH;
304 		case ACPI_PIN_CONFIG_PULLDOWN:
305 			return polarity == GPIO_ACTIVE_LOW ? GPIOD_OUT_HIGH : GPIOD_OUT_LOW;
306 		default:
307 			break;
308 		}
309 		break;
310 	default:
311 		break;
312 	}
313 
314 	/*
315 	 * Assume that the BIOS has configured the direction and pull
316 	 * accordingly.
317 	 */
318 	return GPIOD_ASIS;
319 }
320 
321 static struct gpio_desc *acpi_request_own_gpiod(struct gpio_chip *chip,
322 						struct acpi_resource_gpio *agpio,
323 						unsigned int index,
324 						const char *label)
325 {
326 	int polarity = GPIO_ACTIVE_HIGH;
327 	enum gpiod_flags flags = acpi_gpio_to_gpiod_flags(agpio, polarity);
328 	unsigned int pin = agpio->pin_table[index];
329 	struct gpio_desc *desc;
330 	int ret;
331 
332 	desc = gpiochip_request_own_desc(chip, pin, label, polarity, flags);
333 	if (IS_ERR(desc))
334 		return desc;
335 
336 	/* ACPI uses hundredths of milliseconds units */
337 	ret = gpio_set_debounce_timeout(desc, agpio->debounce_timeout * 10);
338 	if (ret)
339 		dev_warn(chip->parent,
340 			 "Failed to set debounce-timeout for pin 0x%04X, err %d\n",
341 			 pin, ret);
342 
343 	return desc;
344 }
345 
346 static bool acpi_gpio_in_ignore_list(const char *ignore_list, const char *controller_in,
347 				     unsigned int pin_in)
348 {
349 	const char *controller, *pin_str;
350 	unsigned int pin;
351 	char *endp;
352 	int len;
353 
354 	controller = ignore_list;
355 	while (controller) {
356 		pin_str = strchr(controller, '@');
357 		if (!pin_str)
358 			goto err;
359 
360 		len = pin_str - controller;
361 		if (len == strlen(controller_in) &&
362 		    strncmp(controller, controller_in, len) == 0) {
363 			pin = simple_strtoul(pin_str + 1, &endp, 10);
364 			if (*endp != 0 && *endp != ',')
365 				goto err;
366 
367 			if (pin == pin_in)
368 				return true;
369 		}
370 
371 		controller = strchr(controller, ',');
372 		if (controller)
373 			controller++;
374 	}
375 
376 	return false;
377 err:
378 	pr_err_once("Error: Invalid value for gpiolib_acpi.ignore_...: %s\n", ignore_list);
379 	return false;
380 }
381 
382 static bool acpi_gpio_irq_is_wake(struct device *parent,
383 				  const struct acpi_resource_gpio *agpio)
384 {
385 	unsigned int pin = agpio->pin_table[0];
386 
387 	if (agpio->wake_capable != ACPI_WAKE_CAPABLE)
388 		return false;
389 
390 	if (acpi_gpio_in_ignore_list(ignore_wake, dev_name(parent), pin)) {
391 		dev_info(parent, "Ignoring wakeup on pin %u\n", pin);
392 		return false;
393 	}
394 
395 	return true;
396 }
397 
398 /* Always returns AE_OK so that we keep looping over the resources */
399 static acpi_status acpi_gpiochip_alloc_event(struct acpi_resource *ares,
400 					     void *context)
401 {
402 	struct acpi_gpio_chip *acpi_gpio = context;
403 	struct gpio_chip *chip = acpi_gpio->chip;
404 	struct acpi_resource_gpio *agpio;
405 	acpi_handle handle, evt_handle;
406 	struct acpi_gpio_event *event;
407 	irq_handler_t handler = NULL;
408 	struct gpio_desc *desc;
409 	unsigned int pin;
410 	int ret, irq;
411 
412 	if (!acpi_gpio_get_irq_resource(ares, &agpio))
413 		return AE_OK;
414 
415 	handle = ACPI_HANDLE(chip->parent);
416 	pin = agpio->pin_table[0];
417 
418 	if (pin <= 255) {
419 		char ev_name[8];
420 		sprintf(ev_name, "_%c%02X",
421 			agpio->triggering == ACPI_EDGE_SENSITIVE ? 'E' : 'L',
422 			pin);
423 		if (ACPI_SUCCESS(acpi_get_handle(handle, ev_name, &evt_handle)))
424 			handler = acpi_gpio_irq_handler;
425 	}
426 	if (!handler) {
427 		if (ACPI_SUCCESS(acpi_get_handle(handle, "_EVT", &evt_handle)))
428 			handler = acpi_gpio_irq_handler_evt;
429 	}
430 	if (!handler)
431 		return AE_OK;
432 
433 	if (acpi_gpio_in_ignore_list(ignore_interrupt, dev_name(chip->parent), pin)) {
434 		dev_info(chip->parent, "Ignoring interrupt on pin %u\n", pin);
435 		return AE_OK;
436 	}
437 
438 	desc = acpi_request_own_gpiod(chip, agpio, 0, "ACPI:Event");
439 	if (IS_ERR(desc)) {
440 		dev_err(chip->parent,
441 			"Failed to request GPIO for pin 0x%04X, err %ld\n",
442 			pin, PTR_ERR(desc));
443 		return AE_OK;
444 	}
445 
446 	ret = gpiochip_lock_as_irq(chip, pin);
447 	if (ret) {
448 		dev_err(chip->parent,
449 			"Failed to lock GPIO pin 0x%04X as interrupt, err %d\n",
450 			pin, ret);
451 		goto fail_free_desc;
452 	}
453 
454 	irq = gpiod_to_irq(desc);
455 	if (irq < 0) {
456 		dev_err(chip->parent,
457 			"Failed to translate GPIO pin 0x%04X to IRQ, err %d\n",
458 			pin, irq);
459 		goto fail_unlock_irq;
460 	}
461 
462 	event = kzalloc(sizeof(*event), GFP_KERNEL);
463 	if (!event)
464 		goto fail_unlock_irq;
465 
466 	event->irqflags = IRQF_ONESHOT;
467 	if (agpio->triggering == ACPI_LEVEL_SENSITIVE) {
468 		if (agpio->polarity == ACPI_ACTIVE_HIGH)
469 			event->irqflags |= IRQF_TRIGGER_HIGH;
470 		else
471 			event->irqflags |= IRQF_TRIGGER_LOW;
472 	} else {
473 		switch (agpio->polarity) {
474 		case ACPI_ACTIVE_HIGH:
475 			event->irqflags |= IRQF_TRIGGER_RISING;
476 			break;
477 		case ACPI_ACTIVE_LOW:
478 			event->irqflags |= IRQF_TRIGGER_FALLING;
479 			break;
480 		default:
481 			event->irqflags |= IRQF_TRIGGER_RISING |
482 					   IRQF_TRIGGER_FALLING;
483 			break;
484 		}
485 	}
486 
487 	event->handle = evt_handle;
488 	event->handler = handler;
489 	event->irq = irq;
490 	event->irq_is_wake = acpi_gpio_irq_is_wake(chip->parent, agpio);
491 	event->pin = pin;
492 	event->desc = desc;
493 
494 	list_add_tail(&event->node, &acpi_gpio->events);
495 
496 	return AE_OK;
497 
498 fail_unlock_irq:
499 	gpiochip_unlock_as_irq(chip, pin);
500 fail_free_desc:
501 	gpiochip_free_own_desc(desc);
502 
503 	return AE_OK;
504 }
505 
506 /**
507  * acpi_gpiochip_request_interrupts() - Register isr for gpio chip ACPI events
508  * @chip:      GPIO chip
509  *
510  * ACPI5 platforms can use GPIO signaled ACPI events. These GPIO interrupts are
511  * handled by ACPI event methods which need to be called from the GPIO
512  * chip's interrupt handler. acpi_gpiochip_request_interrupts() finds out which
513  * GPIO pins have ACPI event methods and assigns interrupt handlers that calls
514  * the ACPI event methods for those pins.
515  */
516 void acpi_gpiochip_request_interrupts(struct gpio_chip *chip)
517 {
518 	struct acpi_gpio_chip *acpi_gpio;
519 	acpi_handle handle;
520 	acpi_status status;
521 	bool defer;
522 
523 	if (!chip->parent || !chip->to_irq)
524 		return;
525 
526 	handle = ACPI_HANDLE(chip->parent);
527 	if (!handle)
528 		return;
529 
530 	status = acpi_get_data(handle, acpi_gpio_chip_dh, (void **)&acpi_gpio);
531 	if (ACPI_FAILURE(status))
532 		return;
533 
534 	if (acpi_quirk_skip_gpio_event_handlers())
535 		return;
536 
537 	acpi_walk_resources(handle, METHOD_NAME__AEI,
538 			    acpi_gpiochip_alloc_event, acpi_gpio);
539 
540 	mutex_lock(&acpi_gpio_deferred_req_irqs_lock);
541 	defer = !acpi_gpio_deferred_req_irqs_done;
542 	if (defer)
543 		list_add(&acpi_gpio->deferred_req_irqs_list_entry,
544 			 &acpi_gpio_deferred_req_irqs_list);
545 	mutex_unlock(&acpi_gpio_deferred_req_irqs_lock);
546 
547 	if (defer)
548 		return;
549 
550 	acpi_gpiochip_request_irqs(acpi_gpio);
551 }
552 EXPORT_SYMBOL_GPL(acpi_gpiochip_request_interrupts);
553 
554 /**
555  * acpi_gpiochip_free_interrupts() - Free GPIO ACPI event interrupts.
556  * @chip:      GPIO chip
557  *
558  * Free interrupts associated with GPIO ACPI event method for the given
559  * GPIO chip.
560  */
561 void acpi_gpiochip_free_interrupts(struct gpio_chip *chip)
562 {
563 	struct acpi_gpio_chip *acpi_gpio;
564 	struct acpi_gpio_event *event, *ep;
565 	acpi_handle handle;
566 	acpi_status status;
567 
568 	if (!chip->parent || !chip->to_irq)
569 		return;
570 
571 	handle = ACPI_HANDLE(chip->parent);
572 	if (!handle)
573 		return;
574 
575 	status = acpi_get_data(handle, acpi_gpio_chip_dh, (void **)&acpi_gpio);
576 	if (ACPI_FAILURE(status))
577 		return;
578 
579 	mutex_lock(&acpi_gpio_deferred_req_irqs_lock);
580 	if (!list_empty(&acpi_gpio->deferred_req_irqs_list_entry))
581 		list_del_init(&acpi_gpio->deferred_req_irqs_list_entry);
582 	mutex_unlock(&acpi_gpio_deferred_req_irqs_lock);
583 
584 	list_for_each_entry_safe_reverse(event, ep, &acpi_gpio->events, node) {
585 		if (event->irq_requested) {
586 			if (event->irq_is_wake)
587 				disable_irq_wake(event->irq);
588 
589 			free_irq(event->irq, event);
590 		}
591 
592 		gpiochip_unlock_as_irq(chip, event->pin);
593 		gpiochip_free_own_desc(event->desc);
594 		list_del(&event->node);
595 		kfree(event);
596 	}
597 }
598 EXPORT_SYMBOL_GPL(acpi_gpiochip_free_interrupts);
599 
600 int acpi_dev_add_driver_gpios(struct acpi_device *adev,
601 			      const struct acpi_gpio_mapping *gpios)
602 {
603 	if (adev && gpios) {
604 		adev->driver_gpios = gpios;
605 		return 0;
606 	}
607 	return -EINVAL;
608 }
609 EXPORT_SYMBOL_GPL(acpi_dev_add_driver_gpios);
610 
611 void acpi_dev_remove_driver_gpios(struct acpi_device *adev)
612 {
613 	if (adev)
614 		adev->driver_gpios = NULL;
615 }
616 EXPORT_SYMBOL_GPL(acpi_dev_remove_driver_gpios);
617 
618 static void acpi_dev_release_driver_gpios(void *adev)
619 {
620 	acpi_dev_remove_driver_gpios(adev);
621 }
622 
623 int devm_acpi_dev_add_driver_gpios(struct device *dev,
624 				   const struct acpi_gpio_mapping *gpios)
625 {
626 	struct acpi_device *adev = ACPI_COMPANION(dev);
627 	int ret;
628 
629 	ret = acpi_dev_add_driver_gpios(adev, gpios);
630 	if (ret)
631 		return ret;
632 
633 	return devm_add_action_or_reset(dev, acpi_dev_release_driver_gpios, adev);
634 }
635 EXPORT_SYMBOL_GPL(devm_acpi_dev_add_driver_gpios);
636 
637 static bool acpi_get_driver_gpio_data(struct acpi_device *adev,
638 				      const char *name, int index,
639 				      struct fwnode_reference_args *args,
640 				      unsigned int *quirks)
641 {
642 	const struct acpi_gpio_mapping *gm;
643 
644 	if (!adev || !adev->driver_gpios)
645 		return false;
646 
647 	for (gm = adev->driver_gpios; gm->name; gm++)
648 		if (!strcmp(name, gm->name) && gm->data && index < gm->size) {
649 			const struct acpi_gpio_params *par = gm->data + index;
650 
651 			args->fwnode = acpi_fwnode_handle(adev);
652 			args->args[0] = par->crs_entry_index;
653 			args->args[1] = par->line_index;
654 			args->args[2] = par->active_low;
655 			args->nargs = 3;
656 
657 			*quirks = gm->quirks;
658 			return true;
659 		}
660 
661 	return false;
662 }
663 
664 static int
665 __acpi_gpio_update_gpiod_flags(enum gpiod_flags *flags, enum gpiod_flags update)
666 {
667 	const enum gpiod_flags mask =
668 		GPIOD_FLAGS_BIT_DIR_SET | GPIOD_FLAGS_BIT_DIR_OUT |
669 		GPIOD_FLAGS_BIT_DIR_VAL;
670 	int ret = 0;
671 
672 	/*
673 	 * Check if the BIOS has IoRestriction with explicitly set direction
674 	 * and update @flags accordingly. Otherwise use whatever caller asked
675 	 * for.
676 	 */
677 	if (update & GPIOD_FLAGS_BIT_DIR_SET) {
678 		enum gpiod_flags diff = *flags ^ update;
679 
680 		/*
681 		 * Check if caller supplied incompatible GPIO initialization
682 		 * flags.
683 		 *
684 		 * Return %-EINVAL to notify that firmware has different
685 		 * settings and we are going to use them.
686 		 */
687 		if (((*flags & GPIOD_FLAGS_BIT_DIR_SET) && (diff & GPIOD_FLAGS_BIT_DIR_OUT)) ||
688 		    ((*flags & GPIOD_FLAGS_BIT_DIR_OUT) && (diff & GPIOD_FLAGS_BIT_DIR_VAL)))
689 			ret = -EINVAL;
690 		*flags = (*flags & ~mask) | (update & mask);
691 	}
692 	return ret;
693 }
694 
695 static int acpi_gpio_update_gpiod_flags(enum gpiod_flags *flags,
696 				        struct acpi_gpio_info *info)
697 {
698 	struct device *dev = &info->adev->dev;
699 	enum gpiod_flags old = *flags;
700 	int ret;
701 
702 	ret = __acpi_gpio_update_gpiod_flags(&old, info->flags);
703 	if (info->quirks & ACPI_GPIO_QUIRK_NO_IO_RESTRICTION) {
704 		if (ret)
705 			dev_warn(dev, FW_BUG "GPIO not in correct mode, fixing\n");
706 	} else {
707 		if (ret)
708 			dev_dbg(dev, "Override GPIO initialization flags\n");
709 		*flags = old;
710 	}
711 
712 	return ret;
713 }
714 
715 static int acpi_gpio_update_gpiod_lookup_flags(unsigned long *lookupflags,
716 					       struct acpi_gpio_info *info)
717 {
718 	switch (info->pin_config) {
719 	case ACPI_PIN_CONFIG_PULLUP:
720 		*lookupflags |= GPIO_PULL_UP;
721 		break;
722 	case ACPI_PIN_CONFIG_PULLDOWN:
723 		*lookupflags |= GPIO_PULL_DOWN;
724 		break;
725 	case ACPI_PIN_CONFIG_NOPULL:
726 		*lookupflags |= GPIO_PULL_DISABLE;
727 		break;
728 	default:
729 		break;
730 	}
731 
732 	if (info->polarity == GPIO_ACTIVE_LOW)
733 		*lookupflags |= GPIO_ACTIVE_LOW;
734 
735 	return 0;
736 }
737 
738 struct acpi_gpio_lookup {
739 	struct acpi_gpio_info info;
740 	int index;
741 	u16 pin_index;
742 	bool active_low;
743 	struct gpio_desc *desc;
744 	int n;
745 };
746 
747 static int acpi_populate_gpio_lookup(struct acpi_resource *ares, void *data)
748 {
749 	struct acpi_gpio_lookup *lookup = data;
750 
751 	if (ares->type != ACPI_RESOURCE_TYPE_GPIO)
752 		return 1;
753 
754 	if (!lookup->desc) {
755 		const struct acpi_resource_gpio *agpio = &ares->data.gpio;
756 		bool gpioint = agpio->connection_type == ACPI_RESOURCE_GPIO_TYPE_INT;
757 		struct gpio_desc *desc;
758 		u16 pin_index;
759 
760 		if (lookup->info.quirks & ACPI_GPIO_QUIRK_ONLY_GPIOIO && gpioint)
761 			lookup->index++;
762 
763 		if (lookup->n++ != lookup->index)
764 			return 1;
765 
766 		pin_index = lookup->pin_index;
767 		if (pin_index >= agpio->pin_table_length)
768 			return 1;
769 
770 		if (lookup->info.quirks & ACPI_GPIO_QUIRK_ABSOLUTE_NUMBER)
771 			desc = gpio_to_desc(agpio->pin_table[pin_index]);
772 		else
773 			desc = acpi_get_gpiod(agpio->resource_source.string_ptr,
774 					      agpio->pin_table[pin_index]);
775 		lookup->desc = desc;
776 		lookup->info.pin_config = agpio->pin_config;
777 		lookup->info.debounce = agpio->debounce_timeout;
778 		lookup->info.gpioint = gpioint;
779 		lookup->info.wake_capable = acpi_gpio_irq_is_wake(&lookup->info.adev->dev, agpio);
780 
781 		/*
782 		 * Polarity and triggering are only specified for GpioInt
783 		 * resource.
784 		 * Note: we expect here:
785 		 * - ACPI_ACTIVE_LOW == GPIO_ACTIVE_LOW
786 		 * - ACPI_ACTIVE_HIGH == GPIO_ACTIVE_HIGH
787 		 */
788 		if (lookup->info.gpioint) {
789 			lookup->info.polarity = agpio->polarity;
790 			lookup->info.triggering = agpio->triggering;
791 		} else {
792 			lookup->info.polarity = lookup->active_low;
793 		}
794 
795 		lookup->info.flags = acpi_gpio_to_gpiod_flags(agpio, lookup->info.polarity);
796 	}
797 
798 	return 1;
799 }
800 
801 static int acpi_gpio_resource_lookup(struct acpi_gpio_lookup *lookup,
802 				     struct acpi_gpio_info *info)
803 {
804 	struct acpi_device *adev = lookup->info.adev;
805 	struct list_head res_list;
806 	int ret;
807 
808 	INIT_LIST_HEAD(&res_list);
809 
810 	ret = acpi_dev_get_resources(adev, &res_list,
811 				     acpi_populate_gpio_lookup,
812 				     lookup);
813 	if (ret < 0)
814 		return ret;
815 
816 	acpi_dev_free_resource_list(&res_list);
817 
818 	if (!lookup->desc)
819 		return -ENOENT;
820 
821 	if (info)
822 		*info = lookup->info;
823 	return 0;
824 }
825 
826 static int acpi_gpio_property_lookup(struct fwnode_handle *fwnode,
827 				     const char *propname, int index,
828 				     struct acpi_gpio_lookup *lookup)
829 {
830 	struct fwnode_reference_args args;
831 	unsigned int quirks = 0;
832 	int ret;
833 
834 	memset(&args, 0, sizeof(args));
835 	ret = __acpi_node_get_property_reference(fwnode, propname, index, 3,
836 						 &args);
837 	if (ret) {
838 		struct acpi_device *adev;
839 
840 		adev = to_acpi_device_node(fwnode);
841 		if (!acpi_get_driver_gpio_data(adev, propname, index, &args, &quirks))
842 			return ret;
843 	}
844 	/*
845 	 * The property was found and resolved, so need to lookup the GPIO based
846 	 * on returned args.
847 	 */
848 	if (!to_acpi_device_node(args.fwnode))
849 		return -EINVAL;
850 	if (args.nargs != 3)
851 		return -EPROTO;
852 
853 	lookup->index = args.args[0];
854 	lookup->pin_index = args.args[1];
855 	lookup->active_low = !!args.args[2];
856 
857 	lookup->info.adev = to_acpi_device_node(args.fwnode);
858 	lookup->info.quirks = quirks;
859 
860 	return 0;
861 }
862 
863 /**
864  * acpi_get_gpiod_by_index() - get a GPIO descriptor from device resources
865  * @adev: pointer to a ACPI device to get GPIO from
866  * @propname: Property name of the GPIO (optional)
867  * @index: index of GpioIo/GpioInt resource (starting from %0)
868  * @info: info pointer to fill in (optional)
869  *
870  * Function goes through ACPI resources for @adev and based on @index looks
871  * up a GpioIo/GpioInt resource, translates it to the Linux GPIO descriptor,
872  * and returns it. @index matches GpioIo/GpioInt resources only so if there
873  * are total %3 GPIO resources, the index goes from %0 to %2.
874  *
875  * If @propname is specified the GPIO is looked using device property. In
876  * that case @index is used to select the GPIO entry in the property value
877  * (in case of multiple).
878  *
879  * If the GPIO cannot be translated or there is an error, an ERR_PTR is
880  * returned.
881  *
882  * Note: if the GPIO resource has multiple entries in the pin list, this
883  * function only returns the first.
884  */
885 static struct gpio_desc *acpi_get_gpiod_by_index(struct acpi_device *adev,
886 						 const char *propname,
887 						 int index,
888 						 struct acpi_gpio_info *info)
889 {
890 	struct acpi_gpio_lookup lookup;
891 	int ret;
892 
893 	memset(&lookup, 0, sizeof(lookup));
894 	lookup.index = index;
895 
896 	if (propname) {
897 		dev_dbg(&adev->dev, "GPIO: looking up %s\n", propname);
898 
899 		ret = acpi_gpio_property_lookup(acpi_fwnode_handle(adev),
900 						propname, index, &lookup);
901 		if (ret)
902 			return ERR_PTR(ret);
903 
904 		dev_dbg(&adev->dev, "GPIO: _DSD returned %s %d %u %u\n",
905 			dev_name(&lookup.info.adev->dev), lookup.index,
906 			lookup.pin_index, lookup.active_low);
907 	} else {
908 		dev_dbg(&adev->dev, "GPIO: looking up %d in _CRS\n", index);
909 		lookup.info.adev = adev;
910 	}
911 
912 	ret = acpi_gpio_resource_lookup(&lookup, info);
913 	return ret ? ERR_PTR(ret) : lookup.desc;
914 }
915 
916 /**
917  * acpi_get_gpiod_from_data() - get a GPIO descriptor from ACPI data node
918  * @fwnode: pointer to an ACPI firmware node to get the GPIO information from
919  * @propname: Property name of the GPIO
920  * @index: index of GpioIo/GpioInt resource (starting from %0)
921  * @info: info pointer to fill in (optional)
922  *
923  * This function uses the property-based GPIO lookup to get to the GPIO
924  * resource with the relevant information from a data-only ACPI firmware node
925  * and uses that to obtain the GPIO descriptor to return.
926  *
927  * If the GPIO cannot be translated or there is an error an ERR_PTR is
928  * returned.
929  */
930 static struct gpio_desc *acpi_get_gpiod_from_data(struct fwnode_handle *fwnode,
931 						  const char *propname,
932 						  int index,
933 						  struct acpi_gpio_info *info)
934 {
935 	struct acpi_gpio_lookup lookup;
936 	int ret;
937 
938 	if (!is_acpi_data_node(fwnode))
939 		return ERR_PTR(-ENODEV);
940 
941 	if (!propname)
942 		return ERR_PTR(-EINVAL);
943 
944 	memset(&lookup, 0, sizeof(lookup));
945 	lookup.index = index;
946 
947 	ret = acpi_gpio_property_lookup(fwnode, propname, index, &lookup);
948 	if (ret)
949 		return ERR_PTR(ret);
950 
951 	ret = acpi_gpio_resource_lookup(&lookup, info);
952 	return ret ? ERR_PTR(ret) : lookup.desc;
953 }
954 
955 static bool acpi_can_fallback_to_crs(struct acpi_device *adev,
956 				     const char *con_id)
957 {
958 	/* If there is no ACPI device, there is no _CRS to fall back to */
959 	if (!adev)
960 		return false;
961 
962 	/* Never allow fallback if the device has properties */
963 	if (acpi_dev_has_props(adev) || adev->driver_gpios)
964 		return false;
965 
966 	return con_id == NULL;
967 }
968 
969 static struct gpio_desc *
970 __acpi_find_gpio(struct fwnode_handle *fwnode, const char *con_id, unsigned int idx,
971 		 bool can_fallback, struct acpi_gpio_info *info)
972 {
973 	struct acpi_device *adev = to_acpi_device_node(fwnode);
974 	struct gpio_desc *desc;
975 	char propname[32];
976 	int i;
977 
978 	/* Try first from _DSD */
979 	for (i = 0; i < ARRAY_SIZE(gpio_suffixes); i++) {
980 		if (con_id) {
981 			snprintf(propname, sizeof(propname), "%s-%s",
982 				 con_id, gpio_suffixes[i]);
983 		} else {
984 			snprintf(propname, sizeof(propname), "%s",
985 				 gpio_suffixes[i]);
986 		}
987 
988 		if (adev)
989 			desc = acpi_get_gpiod_by_index(adev,
990 						       propname, idx, info);
991 		else
992 			desc = acpi_get_gpiod_from_data(fwnode,
993 							propname, idx, info);
994 		if (PTR_ERR(desc) == -EPROBE_DEFER)
995 			return ERR_CAST(desc);
996 
997 		if (!IS_ERR(desc))
998 			return desc;
999 	}
1000 
1001 	/* Then from plain _CRS GPIOs */
1002 	if (can_fallback)
1003 		return acpi_get_gpiod_by_index(adev, NULL, idx, info);
1004 
1005 	return ERR_PTR(-ENOENT);
1006 }
1007 
1008 struct gpio_desc *acpi_find_gpio(struct fwnode_handle *fwnode,
1009 				 const char *con_id,
1010 				 unsigned int idx,
1011 				 enum gpiod_flags *dflags,
1012 				 unsigned long *lookupflags)
1013 {
1014 	struct acpi_device *adev = to_acpi_device_node(fwnode);
1015 	bool can_fallback = acpi_can_fallback_to_crs(adev, con_id);
1016 	struct acpi_gpio_info info;
1017 	struct gpio_desc *desc;
1018 
1019 	desc = __acpi_find_gpio(fwnode, con_id, idx, can_fallback, &info);
1020 	if (IS_ERR(desc))
1021 		return desc;
1022 
1023 	if (info.gpioint &&
1024 	    (*dflags == GPIOD_OUT_LOW || *dflags == GPIOD_OUT_HIGH)) {
1025 		dev_dbg(&adev->dev, "refusing GpioInt() entry when doing GPIOD_OUT_* lookup\n");
1026 		return ERR_PTR(-ENOENT);
1027 	}
1028 
1029 	acpi_gpio_update_gpiod_flags(dflags, &info);
1030 	acpi_gpio_update_gpiod_lookup_flags(lookupflags, &info);
1031 	return desc;
1032 }
1033 
1034 /**
1035  * acpi_dev_gpio_irq_wake_get_by() - Find GpioInt and translate it to Linux IRQ number
1036  * @adev: pointer to a ACPI device to get IRQ from
1037  * @con_id: optional name of GpioInt resource
1038  * @index: index of GpioInt resource (starting from %0)
1039  * @wake_capable: Set to true if the IRQ is wake capable
1040  *
1041  * If the device has one or more GpioInt resources, this function can be
1042  * used to translate from the GPIO offset in the resource to the Linux IRQ
1043  * number.
1044  *
1045  * The function is idempotent, though each time it runs it will configure GPIO
1046  * pin direction according to the flags in GpioInt resource.
1047  *
1048  * The function takes optional @con_id parameter. If the resource has
1049  * a @con_id in a property, then only those will be taken into account.
1050  *
1051  * The GPIO is considered wake capable if the GpioInt resource specifies
1052  * SharedAndWake or ExclusiveAndWake.
1053  *
1054  * Return: Linux IRQ number (> %0) on success, negative errno on failure.
1055  */
1056 int acpi_dev_gpio_irq_wake_get_by(struct acpi_device *adev, const char *con_id, int index,
1057 				  bool *wake_capable)
1058 {
1059 	struct fwnode_handle *fwnode = acpi_fwnode_handle(adev);
1060 	int idx, i;
1061 	unsigned int irq_flags;
1062 	int ret;
1063 
1064 	for (i = 0, idx = 0; idx <= index; i++) {
1065 		struct acpi_gpio_info info;
1066 		struct gpio_desc *desc;
1067 
1068 		/* Ignore -EPROBE_DEFER, it only matters if idx matches */
1069 		desc = __acpi_find_gpio(fwnode, con_id, i, true, &info);
1070 		if (IS_ERR(desc) && PTR_ERR(desc) != -EPROBE_DEFER)
1071 			return PTR_ERR(desc);
1072 
1073 		if (info.gpioint && idx++ == index) {
1074 			unsigned long lflags = GPIO_LOOKUP_FLAGS_DEFAULT;
1075 			enum gpiod_flags dflags = GPIOD_ASIS;
1076 			char label[32];
1077 			int irq;
1078 
1079 			if (IS_ERR(desc))
1080 				return PTR_ERR(desc);
1081 
1082 			irq = gpiod_to_irq(desc);
1083 			if (irq < 0)
1084 				return irq;
1085 
1086 			acpi_gpio_update_gpiod_flags(&dflags, &info);
1087 			acpi_gpio_update_gpiod_lookup_flags(&lflags, &info);
1088 
1089 			snprintf(label, sizeof(label), "%pfwP GpioInt(%d)", fwnode, index);
1090 			ret = gpiod_set_consumer_name(desc, con_id ?: label);
1091 			if (ret)
1092 				return ret;
1093 
1094 			ret = gpiod_configure_flags(desc, label, lflags, dflags);
1095 			if (ret < 0)
1096 				return ret;
1097 
1098 			/* ACPI uses hundredths of milliseconds units */
1099 			ret = gpio_set_debounce_timeout(desc, info.debounce * 10);
1100 			if (ret)
1101 				return ret;
1102 
1103 			irq_flags = acpi_dev_get_irq_type(info.triggering,
1104 							  info.polarity);
1105 
1106 			/*
1107 			 * If the IRQ is not already in use then set type
1108 			 * if specified and different than the current one.
1109 			 */
1110 			if (can_request_irq(irq, irq_flags)) {
1111 				if (irq_flags != IRQ_TYPE_NONE &&
1112 				    irq_flags != irq_get_trigger_type(irq))
1113 					irq_set_irq_type(irq, irq_flags);
1114 			} else {
1115 				dev_dbg(&adev->dev, "IRQ %d already in use\n", irq);
1116 			}
1117 
1118 			/* avoid suspend issues with GPIOs when systems are using S3 */
1119 			if (wake_capable && acpi_gbl_FADT.flags & ACPI_FADT_LOW_POWER_S0)
1120 				*wake_capable = info.wake_capable;
1121 
1122 			return irq;
1123 		}
1124 
1125 	}
1126 	return -ENOENT;
1127 }
1128 EXPORT_SYMBOL_GPL(acpi_dev_gpio_irq_wake_get_by);
1129 
1130 static acpi_status
1131 acpi_gpio_adr_space_handler(u32 function, acpi_physical_address address,
1132 			    u32 bits, u64 *value, void *handler_context,
1133 			    void *region_context)
1134 {
1135 	struct acpi_gpio_chip *achip = region_context;
1136 	struct gpio_chip *chip = achip->chip;
1137 	struct acpi_resource_gpio *agpio;
1138 	struct acpi_resource *ares;
1139 	u16 pin_index = address;
1140 	acpi_status status;
1141 	int length;
1142 	int i;
1143 
1144 	status = acpi_buffer_to_resource(achip->conn_info.connection,
1145 					 achip->conn_info.length, &ares);
1146 	if (ACPI_FAILURE(status))
1147 		return status;
1148 
1149 	if (WARN_ON(ares->type != ACPI_RESOURCE_TYPE_GPIO)) {
1150 		ACPI_FREE(ares);
1151 		return AE_BAD_PARAMETER;
1152 	}
1153 
1154 	agpio = &ares->data.gpio;
1155 
1156 	if (WARN_ON(agpio->io_restriction == ACPI_IO_RESTRICT_INPUT &&
1157 	    function == ACPI_WRITE)) {
1158 		ACPI_FREE(ares);
1159 		return AE_BAD_PARAMETER;
1160 	}
1161 
1162 	length = min_t(u16, agpio->pin_table_length, pin_index + bits);
1163 	for (i = pin_index; i < length; ++i) {
1164 		unsigned int pin = agpio->pin_table[i];
1165 		struct acpi_gpio_connection *conn;
1166 		struct gpio_desc *desc;
1167 		bool found;
1168 
1169 		mutex_lock(&achip->conn_lock);
1170 
1171 		found = false;
1172 		list_for_each_entry(conn, &achip->conns, node) {
1173 			if (conn->pin == pin) {
1174 				found = true;
1175 				desc = conn->desc;
1176 				break;
1177 			}
1178 		}
1179 
1180 		/*
1181 		 * The same GPIO can be shared between operation region and
1182 		 * event but only if the access here is ACPI_READ. In that
1183 		 * case we "borrow" the event GPIO instead.
1184 		 */
1185 		if (!found && agpio->shareable == ACPI_SHARED &&
1186 		     function == ACPI_READ) {
1187 			struct acpi_gpio_event *event;
1188 
1189 			list_for_each_entry(event, &achip->events, node) {
1190 				if (event->pin == pin) {
1191 					desc = event->desc;
1192 					found = true;
1193 					break;
1194 				}
1195 			}
1196 		}
1197 
1198 		if (!found) {
1199 			desc = acpi_request_own_gpiod(chip, agpio, i, "ACPI:OpRegion");
1200 			if (IS_ERR(desc)) {
1201 				mutex_unlock(&achip->conn_lock);
1202 				status = AE_ERROR;
1203 				goto out;
1204 			}
1205 
1206 			conn = kzalloc(sizeof(*conn), GFP_KERNEL);
1207 			if (!conn) {
1208 				gpiochip_free_own_desc(desc);
1209 				mutex_unlock(&achip->conn_lock);
1210 				status = AE_NO_MEMORY;
1211 				goto out;
1212 			}
1213 
1214 			conn->pin = pin;
1215 			conn->desc = desc;
1216 			list_add_tail(&conn->node, &achip->conns);
1217 		}
1218 
1219 		mutex_unlock(&achip->conn_lock);
1220 
1221 		if (function == ACPI_WRITE)
1222 			gpiod_set_raw_value_cansleep(desc, !!(*value & BIT(i)));
1223 		else
1224 			*value |= (u64)gpiod_get_raw_value_cansleep(desc) << i;
1225 	}
1226 
1227 out:
1228 	ACPI_FREE(ares);
1229 	return status;
1230 }
1231 
1232 static void acpi_gpiochip_request_regions(struct acpi_gpio_chip *achip)
1233 {
1234 	struct gpio_chip *chip = achip->chip;
1235 	acpi_handle handle = ACPI_HANDLE(chip->parent);
1236 	acpi_status status;
1237 
1238 	INIT_LIST_HEAD(&achip->conns);
1239 	mutex_init(&achip->conn_lock);
1240 	status = acpi_install_address_space_handler(handle, ACPI_ADR_SPACE_GPIO,
1241 						    acpi_gpio_adr_space_handler,
1242 						    NULL, achip);
1243 	if (ACPI_FAILURE(status))
1244 		dev_err(chip->parent,
1245 		        "Failed to install GPIO OpRegion handler\n");
1246 }
1247 
1248 static void acpi_gpiochip_free_regions(struct acpi_gpio_chip *achip)
1249 {
1250 	struct gpio_chip *chip = achip->chip;
1251 	acpi_handle handle = ACPI_HANDLE(chip->parent);
1252 	struct acpi_gpio_connection *conn, *tmp;
1253 	acpi_status status;
1254 
1255 	status = acpi_remove_address_space_handler(handle, ACPI_ADR_SPACE_GPIO,
1256 						   acpi_gpio_adr_space_handler);
1257 	if (ACPI_FAILURE(status)) {
1258 		dev_err(chip->parent,
1259 			"Failed to remove GPIO OpRegion handler\n");
1260 		return;
1261 	}
1262 
1263 	list_for_each_entry_safe_reverse(conn, tmp, &achip->conns, node) {
1264 		gpiochip_free_own_desc(conn->desc);
1265 		list_del(&conn->node);
1266 		kfree(conn);
1267 	}
1268 }
1269 
1270 static struct gpio_desc *
1271 acpi_gpiochip_parse_own_gpio(struct acpi_gpio_chip *achip,
1272 			     struct fwnode_handle *fwnode,
1273 			     const char **name,
1274 			     unsigned long *lflags,
1275 			     enum gpiod_flags *dflags)
1276 {
1277 	struct gpio_chip *chip = achip->chip;
1278 	struct gpio_desc *desc;
1279 	u32 gpios[2];
1280 	int ret;
1281 
1282 	*lflags = GPIO_LOOKUP_FLAGS_DEFAULT;
1283 	*dflags = GPIOD_ASIS;
1284 	*name = NULL;
1285 
1286 	ret = fwnode_property_read_u32_array(fwnode, "gpios", gpios,
1287 					     ARRAY_SIZE(gpios));
1288 	if (ret < 0)
1289 		return ERR_PTR(ret);
1290 
1291 	desc = gpiochip_get_desc(chip, gpios[0]);
1292 	if (IS_ERR(desc))
1293 		return desc;
1294 
1295 	if (gpios[1])
1296 		*lflags |= GPIO_ACTIVE_LOW;
1297 
1298 	if (fwnode_property_present(fwnode, "input"))
1299 		*dflags |= GPIOD_IN;
1300 	else if (fwnode_property_present(fwnode, "output-low"))
1301 		*dflags |= GPIOD_OUT_LOW;
1302 	else if (fwnode_property_present(fwnode, "output-high"))
1303 		*dflags |= GPIOD_OUT_HIGH;
1304 	else
1305 		return ERR_PTR(-EINVAL);
1306 
1307 	fwnode_property_read_string(fwnode, "line-name", name);
1308 
1309 	return desc;
1310 }
1311 
1312 static void acpi_gpiochip_scan_gpios(struct acpi_gpio_chip *achip)
1313 {
1314 	struct gpio_chip *chip = achip->chip;
1315 	struct fwnode_handle *fwnode;
1316 
1317 	device_for_each_child_node(chip->parent, fwnode) {
1318 		unsigned long lflags;
1319 		enum gpiod_flags dflags;
1320 		struct gpio_desc *desc;
1321 		const char *name;
1322 		int ret;
1323 
1324 		if (!fwnode_property_present(fwnode, "gpio-hog"))
1325 			continue;
1326 
1327 		desc = acpi_gpiochip_parse_own_gpio(achip, fwnode, &name,
1328 						    &lflags, &dflags);
1329 		if (IS_ERR(desc))
1330 			continue;
1331 
1332 		ret = gpiod_hog(desc, name, lflags, dflags);
1333 		if (ret) {
1334 			dev_err(chip->parent, "Failed to hog GPIO\n");
1335 			fwnode_handle_put(fwnode);
1336 			return;
1337 		}
1338 	}
1339 }
1340 
1341 void acpi_gpiochip_add(struct gpio_chip *chip)
1342 {
1343 	struct acpi_gpio_chip *acpi_gpio;
1344 	struct acpi_device *adev;
1345 	acpi_status status;
1346 
1347 	if (!chip || !chip->parent)
1348 		return;
1349 
1350 	adev = ACPI_COMPANION(chip->parent);
1351 	if (!adev)
1352 		return;
1353 
1354 	acpi_gpio = kzalloc(sizeof(*acpi_gpio), GFP_KERNEL);
1355 	if (!acpi_gpio) {
1356 		dev_err(chip->parent,
1357 			"Failed to allocate memory for ACPI GPIO chip\n");
1358 		return;
1359 	}
1360 
1361 	acpi_gpio->chip = chip;
1362 	INIT_LIST_HEAD(&acpi_gpio->events);
1363 	INIT_LIST_HEAD(&acpi_gpio->deferred_req_irqs_list_entry);
1364 
1365 	status = acpi_attach_data(adev->handle, acpi_gpio_chip_dh, acpi_gpio);
1366 	if (ACPI_FAILURE(status)) {
1367 		dev_err(chip->parent, "Failed to attach ACPI GPIO chip\n");
1368 		kfree(acpi_gpio);
1369 		return;
1370 	}
1371 
1372 	acpi_gpiochip_request_regions(acpi_gpio);
1373 	acpi_gpiochip_scan_gpios(acpi_gpio);
1374 	acpi_dev_clear_dependencies(adev);
1375 }
1376 
1377 void acpi_gpiochip_remove(struct gpio_chip *chip)
1378 {
1379 	struct acpi_gpio_chip *acpi_gpio;
1380 	acpi_handle handle;
1381 	acpi_status status;
1382 
1383 	if (!chip || !chip->parent)
1384 		return;
1385 
1386 	handle = ACPI_HANDLE(chip->parent);
1387 	if (!handle)
1388 		return;
1389 
1390 	status = acpi_get_data(handle, acpi_gpio_chip_dh, (void **)&acpi_gpio);
1391 	if (ACPI_FAILURE(status)) {
1392 		dev_warn(chip->parent, "Failed to retrieve ACPI GPIO chip\n");
1393 		return;
1394 	}
1395 
1396 	acpi_gpiochip_free_regions(acpi_gpio);
1397 
1398 	acpi_detach_data(handle, acpi_gpio_chip_dh);
1399 	kfree(acpi_gpio);
1400 }
1401 
1402 static int acpi_gpio_package_count(const union acpi_object *obj)
1403 {
1404 	const union acpi_object *element = obj->package.elements;
1405 	const union acpi_object *end = element + obj->package.count;
1406 	unsigned int count = 0;
1407 
1408 	while (element < end) {
1409 		switch (element->type) {
1410 		case ACPI_TYPE_LOCAL_REFERENCE:
1411 			element += 3;
1412 			fallthrough;
1413 		case ACPI_TYPE_INTEGER:
1414 			element++;
1415 			count++;
1416 			break;
1417 
1418 		default:
1419 			return -EPROTO;
1420 		}
1421 	}
1422 
1423 	return count;
1424 }
1425 
1426 static int acpi_find_gpio_count(struct acpi_resource *ares, void *data)
1427 {
1428 	unsigned int *count = data;
1429 
1430 	if (ares->type == ACPI_RESOURCE_TYPE_GPIO)
1431 		*count += ares->data.gpio.pin_table_length;
1432 
1433 	return 1;
1434 }
1435 
1436 /**
1437  * acpi_gpio_count - count the GPIOs associated with a firmware node / function
1438  * @fwnode:	firmware node of the GPIO consumer
1439  * @con_id:	function within the GPIO consumer
1440  *
1441  * Return:
1442  * The number of GPIOs associated with a firmware node / function or %-ENOENT,
1443  * if no GPIO has been assigned to the requested function.
1444  */
1445 int acpi_gpio_count(const struct fwnode_handle *fwnode, const char *con_id)
1446 {
1447 	struct acpi_device *adev = to_acpi_device_node(fwnode);
1448 	const union acpi_object *obj;
1449 	const struct acpi_gpio_mapping *gm;
1450 	int count = -ENOENT;
1451 	int ret;
1452 	char propname[32];
1453 	unsigned int i;
1454 
1455 	/* Try first from _DSD */
1456 	for (i = 0; i < ARRAY_SIZE(gpio_suffixes); i++) {
1457 		if (con_id)
1458 			snprintf(propname, sizeof(propname), "%s-%s",
1459 				 con_id, gpio_suffixes[i]);
1460 		else
1461 			snprintf(propname, sizeof(propname), "%s",
1462 				 gpio_suffixes[i]);
1463 
1464 		ret = acpi_dev_get_property(adev, propname, ACPI_TYPE_ANY, &obj);
1465 		if (ret == 0) {
1466 			if (obj->type == ACPI_TYPE_LOCAL_REFERENCE)
1467 				count = 1;
1468 			else if (obj->type == ACPI_TYPE_PACKAGE)
1469 				count = acpi_gpio_package_count(obj);
1470 		} else if (adev->driver_gpios) {
1471 			for (gm = adev->driver_gpios; gm->name; gm++)
1472 				if (strcmp(propname, gm->name) == 0) {
1473 					count = gm->size;
1474 					break;
1475 				}
1476 		}
1477 		if (count > 0)
1478 			break;
1479 	}
1480 
1481 	/* Then from plain _CRS GPIOs */
1482 	if (count < 0) {
1483 		struct list_head resource_list;
1484 		unsigned int crs_count = 0;
1485 
1486 		if (!acpi_can_fallback_to_crs(adev, con_id))
1487 			return count;
1488 
1489 		INIT_LIST_HEAD(&resource_list);
1490 		acpi_dev_get_resources(adev, &resource_list,
1491 				       acpi_find_gpio_count, &crs_count);
1492 		acpi_dev_free_resource_list(&resource_list);
1493 		if (crs_count > 0)
1494 			count = crs_count;
1495 	}
1496 	return count ? count : -ENOENT;
1497 }
1498 
1499 /* Run deferred acpi_gpiochip_request_irqs() */
1500 static int __init acpi_gpio_handle_deferred_request_irqs(void)
1501 {
1502 	struct acpi_gpio_chip *acpi_gpio, *tmp;
1503 
1504 	mutex_lock(&acpi_gpio_deferred_req_irqs_lock);
1505 	list_for_each_entry_safe(acpi_gpio, tmp,
1506 				 &acpi_gpio_deferred_req_irqs_list,
1507 				 deferred_req_irqs_list_entry)
1508 		acpi_gpiochip_request_irqs(acpi_gpio);
1509 
1510 	acpi_gpio_deferred_req_irqs_done = true;
1511 	mutex_unlock(&acpi_gpio_deferred_req_irqs_lock);
1512 
1513 	return 0;
1514 }
1515 /* We must use _sync so that this runs after the first deferred_probe run */
1516 late_initcall_sync(acpi_gpio_handle_deferred_request_irqs);
1517 
1518 static const struct dmi_system_id gpiolib_acpi_quirks[] __initconst = {
1519 	{
1520 		/*
1521 		 * The Minix Neo Z83-4 has a micro-USB-B id-pin handler for
1522 		 * a non existing micro-USB-B connector which puts the HDMI
1523 		 * DDC pins in GPIO mode, breaking HDMI support.
1524 		 */
1525 		.matches = {
1526 			DMI_MATCH(DMI_SYS_VENDOR, "MINIX"),
1527 			DMI_MATCH(DMI_PRODUCT_NAME, "Z83-4"),
1528 		},
1529 		.driver_data = &(struct acpi_gpiolib_dmi_quirk) {
1530 			.no_edge_events_on_boot = true,
1531 		},
1532 	},
1533 	{
1534 		/*
1535 		 * The Terra Pad 1061 has a micro-USB-B id-pin handler, which
1536 		 * instead of controlling the actual micro-USB-B turns the 5V
1537 		 * boost for its USB-A connector off. The actual micro-USB-B
1538 		 * connector is wired for charging only.
1539 		 */
1540 		.matches = {
1541 			DMI_MATCH(DMI_SYS_VENDOR, "Wortmann_AG"),
1542 			DMI_MATCH(DMI_PRODUCT_NAME, "TERRA_PAD_1061"),
1543 		},
1544 		.driver_data = &(struct acpi_gpiolib_dmi_quirk) {
1545 			.no_edge_events_on_boot = true,
1546 		},
1547 	},
1548 	{
1549 		/*
1550 		 * The Dell Venue 10 Pro 5055, with Bay Trail SoC + TI PMIC uses an
1551 		 * external embedded-controller connected via I2C + an ACPI GPIO
1552 		 * event handler on INT33FFC:02 pin 12, causing spurious wakeups.
1553 		 */
1554 		.matches = {
1555 			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
1556 			DMI_MATCH(DMI_PRODUCT_NAME, "Venue 10 Pro 5055"),
1557 		},
1558 		.driver_data = &(struct acpi_gpiolib_dmi_quirk) {
1559 			.ignore_wake = "INT33FC:02@12",
1560 		},
1561 	},
1562 	{
1563 		/*
1564 		 * HP X2 10 models with Cherry Trail SoC + TI PMIC use an
1565 		 * external embedded-controller connected via I2C + an ACPI GPIO
1566 		 * event handler on INT33FF:01 pin 0, causing spurious wakeups.
1567 		 * When suspending by closing the LID, the power to the USB
1568 		 * keyboard is turned off, causing INT0002 ACPI events to
1569 		 * trigger once the XHCI controller notices the keyboard is
1570 		 * gone. So INT0002 events cause spurious wakeups too. Ignoring
1571 		 * EC wakes breaks wakeup when opening the lid, the user needs
1572 		 * to press the power-button to wakeup the system. The
1573 		 * alternative is suspend simply not working, which is worse.
1574 		 */
1575 		.matches = {
1576 			DMI_MATCH(DMI_SYS_VENDOR, "HP"),
1577 			DMI_MATCH(DMI_PRODUCT_NAME, "HP x2 Detachable 10-p0XX"),
1578 		},
1579 		.driver_data = &(struct acpi_gpiolib_dmi_quirk) {
1580 			.ignore_wake = "INT33FF:01@0,INT0002:00@2",
1581 		},
1582 	},
1583 	{
1584 		/*
1585 		 * HP X2 10 models with Bay Trail SoC + AXP288 PMIC use an
1586 		 * external embedded-controller connected via I2C + an ACPI GPIO
1587 		 * event handler on INT33FC:02 pin 28, causing spurious wakeups.
1588 		 */
1589 		.matches = {
1590 			DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
1591 			DMI_MATCH(DMI_PRODUCT_NAME, "HP Pavilion x2 Detachable"),
1592 			DMI_MATCH(DMI_BOARD_NAME, "815D"),
1593 		},
1594 		.driver_data = &(struct acpi_gpiolib_dmi_quirk) {
1595 			.ignore_wake = "INT33FC:02@28",
1596 		},
1597 	},
1598 	{
1599 		/*
1600 		 * HP X2 10 models with Cherry Trail SoC + AXP288 PMIC use an
1601 		 * external embedded-controller connected via I2C + an ACPI GPIO
1602 		 * event handler on INT33FF:01 pin 0, causing spurious wakeups.
1603 		 */
1604 		.matches = {
1605 			DMI_MATCH(DMI_SYS_VENDOR, "HP"),
1606 			DMI_MATCH(DMI_PRODUCT_NAME, "HP Pavilion x2 Detachable"),
1607 			DMI_MATCH(DMI_BOARD_NAME, "813E"),
1608 		},
1609 		.driver_data = &(struct acpi_gpiolib_dmi_quirk) {
1610 			.ignore_wake = "INT33FF:01@0",
1611 		},
1612 	},
1613 	{
1614 		/*
1615 		 * Interrupt storm caused from edge triggered floating pin
1616 		 * Found in BIOS UX325UAZ.300
1617 		 * https://bugzilla.kernel.org/show_bug.cgi?id=216208
1618 		 */
1619 		.matches = {
1620 			DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK COMPUTER INC."),
1621 			DMI_MATCH(DMI_PRODUCT_NAME, "ZenBook UX325UAZ_UM325UAZ"),
1622 		},
1623 		.driver_data = &(struct acpi_gpiolib_dmi_quirk) {
1624 			.ignore_interrupt = "AMDI0030:00@18",
1625 		},
1626 	},
1627 	{
1628 		/*
1629 		 * Spurious wakeups from TP_ATTN# pin
1630 		 * Found in BIOS 1.7.8
1631 		 * https://gitlab.freedesktop.org/drm/amd/-/issues/1722#note_1720627
1632 		 */
1633 		.matches = {
1634 			DMI_MATCH(DMI_BOARD_NAME, "NL5xNU"),
1635 		},
1636 		.driver_data = &(struct acpi_gpiolib_dmi_quirk) {
1637 			.ignore_wake = "ELAN0415:00@9",
1638 		},
1639 	},
1640 	{
1641 		/*
1642 		 * Spurious wakeups from TP_ATTN# pin
1643 		 * Found in BIOS 1.7.8
1644 		 * https://gitlab.freedesktop.org/drm/amd/-/issues/1722#note_1720627
1645 		 */
1646 		.matches = {
1647 			DMI_MATCH(DMI_BOARD_NAME, "NL5xRU"),
1648 		},
1649 		.driver_data = &(struct acpi_gpiolib_dmi_quirk) {
1650 			.ignore_wake = "ELAN0415:00@9",
1651 		},
1652 	},
1653 	{
1654 		/*
1655 		 * Spurious wakeups from TP_ATTN# pin
1656 		 * Found in BIOS 1.7.7
1657 		 */
1658 		.matches = {
1659 			DMI_MATCH(DMI_BOARD_NAME, "NH5xAx"),
1660 		},
1661 		.driver_data = &(struct acpi_gpiolib_dmi_quirk) {
1662 			.ignore_wake = "SYNA1202:00@16",
1663 		},
1664 	},
1665 	{
1666 		/*
1667 		 * On the Peaq C1010 2-in-1 INT33FC:00 pin 3 is connected to
1668 		 * a "dolby" button. At the ACPI level an _AEI event-handler
1669 		 * is connected which sets an ACPI variable to 1 on both
1670 		 * edges. This variable can be polled + cleared to 0 using
1671 		 * WMI. But since the variable is set on both edges the WMI
1672 		 * interface is pretty useless even when polling.
1673 		 * So instead the x86-android-tablets code instantiates
1674 		 * a gpio-keys platform device for it.
1675 		 * Ignore the _AEI handler for the pin, so that it is not busy.
1676 		 */
1677 		.matches = {
1678 			DMI_MATCH(DMI_SYS_VENDOR, "PEAQ"),
1679 			DMI_MATCH(DMI_PRODUCT_NAME, "PEAQ PMM C1010 MD99187"),
1680 		},
1681 		.driver_data = &(struct acpi_gpiolib_dmi_quirk) {
1682 			.ignore_interrupt = "INT33FC:00@3",
1683 		},
1684 	},
1685 	{
1686 		/*
1687 		 * Spurious wakeups from TP_ATTN# pin
1688 		 * Found in BIOS 0.35
1689 		 * https://gitlab.freedesktop.org/drm/amd/-/issues/3073
1690 		 */
1691 		.matches = {
1692 			DMI_MATCH(DMI_SYS_VENDOR, "GPD"),
1693 			DMI_MATCH(DMI_PRODUCT_NAME, "G1619-04"),
1694 		},
1695 		.driver_data = &(struct acpi_gpiolib_dmi_quirk) {
1696 			.ignore_wake = "PNP0C50:00@8",
1697 		},
1698 	},
1699 	{} /* Terminating entry */
1700 };
1701 
1702 static int __init acpi_gpio_setup_params(void)
1703 {
1704 	const struct acpi_gpiolib_dmi_quirk *quirk = NULL;
1705 	const struct dmi_system_id *id;
1706 
1707 	id = dmi_first_match(gpiolib_acpi_quirks);
1708 	if (id)
1709 		quirk = id->driver_data;
1710 
1711 	if (run_edge_events_on_boot < 0) {
1712 		if (quirk && quirk->no_edge_events_on_boot)
1713 			run_edge_events_on_boot = 0;
1714 		else
1715 			run_edge_events_on_boot = 1;
1716 	}
1717 
1718 	if (ignore_wake == NULL && quirk && quirk->ignore_wake)
1719 		ignore_wake = quirk->ignore_wake;
1720 
1721 	if (ignore_interrupt == NULL && quirk && quirk->ignore_interrupt)
1722 		ignore_interrupt = quirk->ignore_interrupt;
1723 
1724 	return 0;
1725 }
1726 
1727 /* Directly after dmi_setup() which runs as core_initcall() */
1728 postcore_initcall(acpi_gpio_setup_params);
1729