xref: /openbmc/linux/drivers/gpio/gpiolib-acpi.c (revision f0417e72)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * ACPI helpers for GPIO API
4  *
5  * Copyright (C) 2012, Intel Corporation
6  * Authors: Mathias Nyman <mathias.nyman@linux.intel.com>
7  *          Mika Westerberg <mika.westerberg@linux.intel.com>
8  */
9 
10 #include <linux/dmi.h>
11 #include <linux/errno.h>
12 #include <linux/gpio/consumer.h>
13 #include <linux/gpio/driver.h>
14 #include <linux/gpio/machine.h>
15 #include <linux/export.h>
16 #include <linux/acpi.h>
17 #include <linux/interrupt.h>
18 #include <linux/mutex.h>
19 #include <linux/pinctrl/pinctrl.h>
20 
21 #include "gpiolib.h"
22 #include "gpiolib-acpi.h"
23 
24 static int run_edge_events_on_boot = -1;
25 module_param(run_edge_events_on_boot, int, 0444);
26 MODULE_PARM_DESC(run_edge_events_on_boot,
27 		 "Run edge _AEI event-handlers at boot: 0=no, 1=yes, -1=auto");
28 
29 static char *ignore_wake;
30 module_param(ignore_wake, charp, 0444);
31 MODULE_PARM_DESC(ignore_wake,
32 		 "controller@pin combos on which to ignore the ACPI wake flag "
33 		 "ignore_wake=controller@pin[,controller@pin[,...]]");
34 
35 static char *ignore_interrupt;
36 module_param(ignore_interrupt, charp, 0444);
37 MODULE_PARM_DESC(ignore_interrupt,
38 		 "controller@pin combos on which to ignore interrupt "
39 		 "ignore_interrupt=controller@pin[,controller@pin[,...]]");
40 
41 struct acpi_gpiolib_dmi_quirk {
42 	bool no_edge_events_on_boot;
43 	char *ignore_wake;
44 	char *ignore_interrupt;
45 };
46 
47 /**
48  * struct acpi_gpio_event - ACPI GPIO event handler data
49  *
50  * @node:	  list-entry of the events list of the struct acpi_gpio_chip
51  * @handle:	  handle of ACPI method to execute when the IRQ triggers
52  * @handler:	  handler function to pass to request_irq() when requesting the IRQ
53  * @pin:	  GPIO pin number on the struct gpio_chip
54  * @irq:	  Linux IRQ number for the event, for request_irq() / free_irq()
55  * @irqflags:	  flags to pass to request_irq() when requesting the IRQ
56  * @irq_is_wake:  If the ACPI flags indicate the IRQ is a wakeup source
57  * @irq_requested:True if request_irq() has been done
58  * @desc:	  struct gpio_desc for the GPIO pin for this event
59  */
60 struct acpi_gpio_event {
61 	struct list_head node;
62 	acpi_handle handle;
63 	irq_handler_t handler;
64 	unsigned int pin;
65 	unsigned int irq;
66 	unsigned long irqflags;
67 	bool irq_is_wake;
68 	bool irq_requested;
69 	struct gpio_desc *desc;
70 };
71 
72 struct acpi_gpio_connection {
73 	struct list_head node;
74 	unsigned int pin;
75 	struct gpio_desc *desc;
76 };
77 
78 struct acpi_gpio_chip {
79 	/*
80 	 * ACPICA requires that the first field of the context parameter
81 	 * passed to acpi_install_address_space_handler() is large enough
82 	 * to hold struct acpi_connection_info.
83 	 */
84 	struct acpi_connection_info conn_info;
85 	struct list_head conns;
86 	struct mutex conn_lock;
87 	struct gpio_chip *chip;
88 	struct list_head events;
89 	struct list_head deferred_req_irqs_list_entry;
90 };
91 
92 /**
93  * struct acpi_gpio_info - ACPI GPIO specific information
94  * @adev: reference to ACPI device which consumes GPIO resource
95  * @flags: GPIO initialization flags
96  * @gpioint: if %true this GPIO is of type GpioInt otherwise type is GpioIo
97  * @pin_config: pin bias as provided by ACPI
98  * @polarity: interrupt polarity as provided by ACPI
99  * @triggering: triggering type as provided by ACPI
100  * @wake_capable: wake capability as provided by ACPI
101  * @debounce: debounce timeout as provided by ACPI
102  * @quirks: Linux specific quirks as provided by struct acpi_gpio_mapping
103  */
104 struct acpi_gpio_info {
105 	struct acpi_device *adev;
106 	enum gpiod_flags flags;
107 	bool gpioint;
108 	int pin_config;
109 	int polarity;
110 	int triggering;
111 	bool wake_capable;
112 	unsigned int debounce;
113 	unsigned int quirks;
114 };
115 
116 /*
117  * For GPIO chips which call acpi_gpiochip_request_interrupts() before late_init
118  * (so builtin drivers) we register the ACPI GpioInt IRQ handlers from a
119  * late_initcall_sync() handler, so that other builtin drivers can register their
120  * OpRegions before the event handlers can run. This list contains GPIO chips
121  * for which the acpi_gpiochip_request_irqs() call has been deferred.
122  */
123 static DEFINE_MUTEX(acpi_gpio_deferred_req_irqs_lock);
124 static LIST_HEAD(acpi_gpio_deferred_req_irqs_list);
125 static bool acpi_gpio_deferred_req_irqs_done;
126 
127 static int acpi_gpiochip_find(struct gpio_chip *gc, void *data)
128 {
129 	return gc->parent && device_match_acpi_handle(gc->parent, data);
130 }
131 
132 /**
133  * acpi_get_gpiod() - Translate ACPI GPIO pin to GPIO descriptor usable with GPIO API
134  * @path:	ACPI GPIO controller full path name, (e.g. "\\_SB.GPO1")
135  * @pin:	ACPI GPIO pin number (0-based, controller-relative)
136  *
137  * Return: GPIO descriptor to use with Linux generic GPIO API, or ERR_PTR
138  * error value. Specifically returns %-EPROBE_DEFER if the referenced GPIO
139  * controller does not have GPIO chip registered at the moment. This is to
140  * support probe deferral.
141  */
142 static struct gpio_desc *acpi_get_gpiod(char *path, unsigned int pin)
143 {
144 	struct gpio_chip *chip;
145 	acpi_handle handle;
146 	acpi_status status;
147 
148 	status = acpi_get_handle(NULL, path, &handle);
149 	if (ACPI_FAILURE(status))
150 		return ERR_PTR(-ENODEV);
151 
152 	chip = gpiochip_find(handle, acpi_gpiochip_find);
153 	if (!chip)
154 		return ERR_PTR(-EPROBE_DEFER);
155 
156 	return gpiochip_get_desc(chip, pin);
157 }
158 
159 /**
160  * acpi_get_and_request_gpiod - Translate ACPI GPIO pin to GPIO descriptor and
161  *                              hold a refcount to the GPIO device.
162  * @path:      ACPI GPIO controller full path name, (e.g. "\\_SB.GPO1")
163  * @pin:       ACPI GPIO pin number (0-based, controller-relative)
164  * @label:     Label to pass to gpiod_request()
165  *
166  * This function is a simple pass-through to acpi_get_gpiod(), except that
167  * as it is intended for use outside of the GPIO layer (in a similar fashion to
168  * gpiod_get_index() for example) it also holds a reference to the GPIO device.
169  */
170 struct gpio_desc *acpi_get_and_request_gpiod(char *path, unsigned int pin, char *label)
171 {
172 	struct gpio_desc *gpio;
173 	int ret;
174 
175 	gpio = acpi_get_gpiod(path, pin);
176 	if (IS_ERR(gpio))
177 		return gpio;
178 
179 	ret = gpiod_request(gpio, label);
180 	if (ret)
181 		return ERR_PTR(ret);
182 
183 	return gpio;
184 }
185 EXPORT_SYMBOL_GPL(acpi_get_and_request_gpiod);
186 
187 static irqreturn_t acpi_gpio_irq_handler(int irq, void *data)
188 {
189 	struct acpi_gpio_event *event = data;
190 
191 	acpi_evaluate_object(event->handle, NULL, NULL, NULL);
192 
193 	return IRQ_HANDLED;
194 }
195 
196 static irqreturn_t acpi_gpio_irq_handler_evt(int irq, void *data)
197 {
198 	struct acpi_gpio_event *event = data;
199 
200 	acpi_execute_simple_method(event->handle, NULL, event->pin);
201 
202 	return IRQ_HANDLED;
203 }
204 
205 static void acpi_gpio_chip_dh(acpi_handle handle, void *data)
206 {
207 	/* The address of this function is used as a key. */
208 }
209 
210 bool acpi_gpio_get_irq_resource(struct acpi_resource *ares,
211 				struct acpi_resource_gpio **agpio)
212 {
213 	struct acpi_resource_gpio *gpio;
214 
215 	if (ares->type != ACPI_RESOURCE_TYPE_GPIO)
216 		return false;
217 
218 	gpio = &ares->data.gpio;
219 	if (gpio->connection_type != ACPI_RESOURCE_GPIO_TYPE_INT)
220 		return false;
221 
222 	*agpio = gpio;
223 	return true;
224 }
225 EXPORT_SYMBOL_GPL(acpi_gpio_get_irq_resource);
226 
227 /**
228  * acpi_gpio_get_io_resource - Fetch details of an ACPI resource if it is a GPIO
229  *			       I/O resource or return False if not.
230  * @ares:	Pointer to the ACPI resource to fetch
231  * @agpio:	Pointer to a &struct acpi_resource_gpio to store the output pointer
232  */
233 bool acpi_gpio_get_io_resource(struct acpi_resource *ares,
234 			       struct acpi_resource_gpio **agpio)
235 {
236 	struct acpi_resource_gpio *gpio;
237 
238 	if (ares->type != ACPI_RESOURCE_TYPE_GPIO)
239 		return false;
240 
241 	gpio = &ares->data.gpio;
242 	if (gpio->connection_type != ACPI_RESOURCE_GPIO_TYPE_IO)
243 		return false;
244 
245 	*agpio = gpio;
246 	return true;
247 }
248 EXPORT_SYMBOL_GPL(acpi_gpio_get_io_resource);
249 
250 static void acpi_gpiochip_request_irq(struct acpi_gpio_chip *acpi_gpio,
251 				      struct acpi_gpio_event *event)
252 {
253 	struct device *parent = acpi_gpio->chip->parent;
254 	int ret, value;
255 
256 	ret = request_threaded_irq(event->irq, NULL, event->handler,
257 				   event->irqflags | IRQF_ONESHOT, "ACPI:Event", event);
258 	if (ret) {
259 		dev_err(parent, "Failed to setup interrupt handler for %d\n", event->irq);
260 		return;
261 	}
262 
263 	if (event->irq_is_wake)
264 		enable_irq_wake(event->irq);
265 
266 	event->irq_requested = true;
267 
268 	/* Make sure we trigger the initial state of edge-triggered IRQs */
269 	if (run_edge_events_on_boot &&
270 	    (event->irqflags & (IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING))) {
271 		value = gpiod_get_raw_value_cansleep(event->desc);
272 		if (((event->irqflags & IRQF_TRIGGER_RISING) && value == 1) ||
273 		    ((event->irqflags & IRQF_TRIGGER_FALLING) && value == 0))
274 			event->handler(event->irq, event);
275 	}
276 }
277 
278 static void acpi_gpiochip_request_irqs(struct acpi_gpio_chip *acpi_gpio)
279 {
280 	struct acpi_gpio_event *event;
281 
282 	list_for_each_entry(event, &acpi_gpio->events, node)
283 		acpi_gpiochip_request_irq(acpi_gpio, event);
284 }
285 
286 static enum gpiod_flags
287 acpi_gpio_to_gpiod_flags(const struct acpi_resource_gpio *agpio, int polarity)
288 {
289 	/* GpioInt() implies input configuration */
290 	if (agpio->connection_type == ACPI_RESOURCE_GPIO_TYPE_INT)
291 		return GPIOD_IN;
292 
293 	switch (agpio->io_restriction) {
294 	case ACPI_IO_RESTRICT_INPUT:
295 		return GPIOD_IN;
296 	case ACPI_IO_RESTRICT_OUTPUT:
297 		/*
298 		 * ACPI GPIO resources don't contain an initial value for the
299 		 * GPIO. Therefore we deduce that value from the pull field
300 		 * and the polarity instead. If the pin is pulled up we assume
301 		 * default to be high, if it is pulled down we assume default
302 		 * to be low, otherwise we leave pin untouched. For active low
303 		 * polarity values will be switched. See also
304 		 * Documentation/firmware-guide/acpi/gpio-properties.rst.
305 		 */
306 		switch (agpio->pin_config) {
307 		case ACPI_PIN_CONFIG_PULLUP:
308 			return polarity == GPIO_ACTIVE_LOW ? GPIOD_OUT_LOW : GPIOD_OUT_HIGH;
309 		case ACPI_PIN_CONFIG_PULLDOWN:
310 			return polarity == GPIO_ACTIVE_LOW ? GPIOD_OUT_HIGH : GPIOD_OUT_LOW;
311 		default:
312 			break;
313 		}
314 		break;
315 	default:
316 		break;
317 	}
318 
319 	/*
320 	 * Assume that the BIOS has configured the direction and pull
321 	 * accordingly.
322 	 */
323 	return GPIOD_ASIS;
324 }
325 
326 static struct gpio_desc *acpi_request_own_gpiod(struct gpio_chip *chip,
327 						struct acpi_resource_gpio *agpio,
328 						unsigned int index,
329 						const char *label)
330 {
331 	int polarity = GPIO_ACTIVE_HIGH;
332 	enum gpiod_flags flags = acpi_gpio_to_gpiod_flags(agpio, polarity);
333 	unsigned int pin = agpio->pin_table[index];
334 	struct gpio_desc *desc;
335 	int ret;
336 
337 	desc = gpiochip_request_own_desc(chip, pin, label, polarity, flags);
338 	if (IS_ERR(desc))
339 		return desc;
340 
341 	/* ACPI uses hundredths of milliseconds units */
342 	ret = gpio_set_debounce_timeout(desc, agpio->debounce_timeout * 10);
343 	if (ret)
344 		dev_warn(chip->parent,
345 			 "Failed to set debounce-timeout for pin 0x%04X, err %d\n",
346 			 pin, ret);
347 
348 	return desc;
349 }
350 
351 static bool acpi_gpio_in_ignore_list(const char *ignore_list, const char *controller_in,
352 				     unsigned int pin_in)
353 {
354 	const char *controller, *pin_str;
355 	unsigned int pin;
356 	char *endp;
357 	int len;
358 
359 	controller = ignore_list;
360 	while (controller) {
361 		pin_str = strchr(controller, '@');
362 		if (!pin_str)
363 			goto err;
364 
365 		len = pin_str - controller;
366 		if (len == strlen(controller_in) &&
367 		    strncmp(controller, controller_in, len) == 0) {
368 			pin = simple_strtoul(pin_str + 1, &endp, 10);
369 			if (*endp != 0 && *endp != ',')
370 				goto err;
371 
372 			if (pin == pin_in)
373 				return true;
374 		}
375 
376 		controller = strchr(controller, ',');
377 		if (controller)
378 			controller++;
379 	}
380 
381 	return false;
382 err:
383 	pr_err_once("Error: Invalid value for gpiolib_acpi.ignore_...: %s\n", ignore_list);
384 	return false;
385 }
386 
387 static bool acpi_gpio_irq_is_wake(struct device *parent,
388 				  const struct acpi_resource_gpio *agpio)
389 {
390 	unsigned int pin = agpio->pin_table[0];
391 
392 	if (agpio->wake_capable != ACPI_WAKE_CAPABLE)
393 		return false;
394 
395 	if (acpi_gpio_in_ignore_list(ignore_wake, dev_name(parent), pin)) {
396 		dev_info(parent, "Ignoring wakeup on pin %u\n", pin);
397 		return false;
398 	}
399 
400 	return true;
401 }
402 
403 /* Always returns AE_OK so that we keep looping over the resources */
404 static acpi_status acpi_gpiochip_alloc_event(struct acpi_resource *ares,
405 					     void *context)
406 {
407 	struct acpi_gpio_chip *acpi_gpio = context;
408 	struct gpio_chip *chip = acpi_gpio->chip;
409 	struct acpi_resource_gpio *agpio;
410 	acpi_handle handle, evt_handle;
411 	struct acpi_gpio_event *event;
412 	irq_handler_t handler = NULL;
413 	struct gpio_desc *desc;
414 	unsigned int pin;
415 	int ret, irq;
416 
417 	if (!acpi_gpio_get_irq_resource(ares, &agpio))
418 		return AE_OK;
419 
420 	handle = ACPI_HANDLE(chip->parent);
421 	pin = agpio->pin_table[0];
422 
423 	if (pin <= 255) {
424 		char ev_name[8];
425 		sprintf(ev_name, "_%c%02X",
426 			agpio->triggering == ACPI_EDGE_SENSITIVE ? 'E' : 'L',
427 			pin);
428 		if (ACPI_SUCCESS(acpi_get_handle(handle, ev_name, &evt_handle)))
429 			handler = acpi_gpio_irq_handler;
430 	}
431 	if (!handler) {
432 		if (ACPI_SUCCESS(acpi_get_handle(handle, "_EVT", &evt_handle)))
433 			handler = acpi_gpio_irq_handler_evt;
434 	}
435 	if (!handler)
436 		return AE_OK;
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 	if (acpi_gpio_in_ignore_list(ignore_interrupt, dev_name(chip->parent), pin)) {
463 		dev_info(chip->parent, "Ignoring interrupt on pin %u\n", pin);
464 		return AE_OK;
465 	}
466 
467 	event = kzalloc(sizeof(*event), GFP_KERNEL);
468 	if (!event)
469 		goto fail_unlock_irq;
470 
471 	event->irqflags = IRQF_ONESHOT;
472 	if (agpio->triggering == ACPI_LEVEL_SENSITIVE) {
473 		if (agpio->polarity == ACPI_ACTIVE_HIGH)
474 			event->irqflags |= IRQF_TRIGGER_HIGH;
475 		else
476 			event->irqflags |= IRQF_TRIGGER_LOW;
477 	} else {
478 		switch (agpio->polarity) {
479 		case ACPI_ACTIVE_HIGH:
480 			event->irqflags |= IRQF_TRIGGER_RISING;
481 			break;
482 		case ACPI_ACTIVE_LOW:
483 			event->irqflags |= IRQF_TRIGGER_FALLING;
484 			break;
485 		default:
486 			event->irqflags |= IRQF_TRIGGER_RISING |
487 					   IRQF_TRIGGER_FALLING;
488 			break;
489 		}
490 	}
491 
492 	event->handle = evt_handle;
493 	event->handler = handler;
494 	event->irq = irq;
495 	event->irq_is_wake = acpi_gpio_irq_is_wake(chip->parent, agpio);
496 	event->pin = pin;
497 	event->desc = desc;
498 
499 	list_add_tail(&event->node, &acpi_gpio->events);
500 
501 	return AE_OK;
502 
503 fail_unlock_irq:
504 	gpiochip_unlock_as_irq(chip, pin);
505 fail_free_desc:
506 	gpiochip_free_own_desc(desc);
507 
508 	return AE_OK;
509 }
510 
511 /**
512  * acpi_gpiochip_request_interrupts() - Register isr for gpio chip ACPI events
513  * @chip:      GPIO chip
514  *
515  * ACPI5 platforms can use GPIO signaled ACPI events. These GPIO interrupts are
516  * handled by ACPI event methods which need to be called from the GPIO
517  * chip's interrupt handler. acpi_gpiochip_request_interrupts() finds out which
518  * GPIO pins have ACPI event methods and assigns interrupt handlers that calls
519  * the ACPI event methods for those pins.
520  */
521 void acpi_gpiochip_request_interrupts(struct gpio_chip *chip)
522 {
523 	struct acpi_gpio_chip *acpi_gpio;
524 	acpi_handle handle;
525 	acpi_status status;
526 	bool defer;
527 
528 	if (!chip->parent || !chip->to_irq)
529 		return;
530 
531 	handle = ACPI_HANDLE(chip->parent);
532 	if (!handle)
533 		return;
534 
535 	status = acpi_get_data(handle, acpi_gpio_chip_dh, (void **)&acpi_gpio);
536 	if (ACPI_FAILURE(status))
537 		return;
538 
539 	if (acpi_quirk_skip_gpio_event_handlers())
540 		return;
541 
542 	acpi_walk_resources(handle, METHOD_NAME__AEI,
543 			    acpi_gpiochip_alloc_event, acpi_gpio);
544 
545 	mutex_lock(&acpi_gpio_deferred_req_irqs_lock);
546 	defer = !acpi_gpio_deferred_req_irqs_done;
547 	if (defer)
548 		list_add(&acpi_gpio->deferred_req_irqs_list_entry,
549 			 &acpi_gpio_deferred_req_irqs_list);
550 	mutex_unlock(&acpi_gpio_deferred_req_irqs_lock);
551 
552 	if (defer)
553 		return;
554 
555 	acpi_gpiochip_request_irqs(acpi_gpio);
556 }
557 EXPORT_SYMBOL_GPL(acpi_gpiochip_request_interrupts);
558 
559 /**
560  * acpi_gpiochip_free_interrupts() - Free GPIO ACPI event interrupts.
561  * @chip:      GPIO chip
562  *
563  * Free interrupts associated with GPIO ACPI event method for the given
564  * GPIO chip.
565  */
566 void acpi_gpiochip_free_interrupts(struct gpio_chip *chip)
567 {
568 	struct acpi_gpio_chip *acpi_gpio;
569 	struct acpi_gpio_event *event, *ep;
570 	acpi_handle handle;
571 	acpi_status status;
572 
573 	if (!chip->parent || !chip->to_irq)
574 		return;
575 
576 	handle = ACPI_HANDLE(chip->parent);
577 	if (!handle)
578 		return;
579 
580 	status = acpi_get_data(handle, acpi_gpio_chip_dh, (void **)&acpi_gpio);
581 	if (ACPI_FAILURE(status))
582 		return;
583 
584 	mutex_lock(&acpi_gpio_deferred_req_irqs_lock);
585 	if (!list_empty(&acpi_gpio->deferred_req_irqs_list_entry))
586 		list_del_init(&acpi_gpio->deferred_req_irqs_list_entry);
587 	mutex_unlock(&acpi_gpio_deferred_req_irqs_lock);
588 
589 	list_for_each_entry_safe_reverse(event, ep, &acpi_gpio->events, node) {
590 		if (event->irq_requested) {
591 			if (event->irq_is_wake)
592 				disable_irq_wake(event->irq);
593 
594 			free_irq(event->irq, event);
595 		}
596 
597 		gpiochip_unlock_as_irq(chip, event->pin);
598 		gpiochip_free_own_desc(event->desc);
599 		list_del(&event->node);
600 		kfree(event);
601 	}
602 }
603 EXPORT_SYMBOL_GPL(acpi_gpiochip_free_interrupts);
604 
605 int acpi_dev_add_driver_gpios(struct acpi_device *adev,
606 			      const struct acpi_gpio_mapping *gpios)
607 {
608 	if (adev && gpios) {
609 		adev->driver_gpios = gpios;
610 		return 0;
611 	}
612 	return -EINVAL;
613 }
614 EXPORT_SYMBOL_GPL(acpi_dev_add_driver_gpios);
615 
616 void acpi_dev_remove_driver_gpios(struct acpi_device *adev)
617 {
618 	if (adev)
619 		adev->driver_gpios = NULL;
620 }
621 EXPORT_SYMBOL_GPL(acpi_dev_remove_driver_gpios);
622 
623 static void acpi_dev_release_driver_gpios(void *adev)
624 {
625 	acpi_dev_remove_driver_gpios(adev);
626 }
627 
628 int devm_acpi_dev_add_driver_gpios(struct device *dev,
629 				   const struct acpi_gpio_mapping *gpios)
630 {
631 	struct acpi_device *adev = ACPI_COMPANION(dev);
632 	int ret;
633 
634 	ret = acpi_dev_add_driver_gpios(adev, gpios);
635 	if (ret)
636 		return ret;
637 
638 	return devm_add_action_or_reset(dev, acpi_dev_release_driver_gpios, adev);
639 }
640 EXPORT_SYMBOL_GPL(devm_acpi_dev_add_driver_gpios);
641 
642 static bool acpi_get_driver_gpio_data(struct acpi_device *adev,
643 				      const char *name, int index,
644 				      struct fwnode_reference_args *args,
645 				      unsigned int *quirks)
646 {
647 	const struct acpi_gpio_mapping *gm;
648 
649 	if (!adev->driver_gpios)
650 		return false;
651 
652 	for (gm = adev->driver_gpios; gm->name; gm++)
653 		if (!strcmp(name, gm->name) && gm->data && index < gm->size) {
654 			const struct acpi_gpio_params *par = gm->data + index;
655 
656 			args->fwnode = acpi_fwnode_handle(adev);
657 			args->args[0] = par->crs_entry_index;
658 			args->args[1] = par->line_index;
659 			args->args[2] = par->active_low;
660 			args->nargs = 3;
661 
662 			*quirks = gm->quirks;
663 			return true;
664 		}
665 
666 	return false;
667 }
668 
669 static int
670 __acpi_gpio_update_gpiod_flags(enum gpiod_flags *flags, enum gpiod_flags update)
671 {
672 	const enum gpiod_flags mask =
673 		GPIOD_FLAGS_BIT_DIR_SET | GPIOD_FLAGS_BIT_DIR_OUT |
674 		GPIOD_FLAGS_BIT_DIR_VAL;
675 	int ret = 0;
676 
677 	/*
678 	 * Check if the BIOS has IoRestriction with explicitly set direction
679 	 * and update @flags accordingly. Otherwise use whatever caller asked
680 	 * for.
681 	 */
682 	if (update & GPIOD_FLAGS_BIT_DIR_SET) {
683 		enum gpiod_flags diff = *flags ^ update;
684 
685 		/*
686 		 * Check if caller supplied incompatible GPIO initialization
687 		 * flags.
688 		 *
689 		 * Return %-EINVAL to notify that firmware has different
690 		 * settings and we are going to use them.
691 		 */
692 		if (((*flags & GPIOD_FLAGS_BIT_DIR_SET) && (diff & GPIOD_FLAGS_BIT_DIR_OUT)) ||
693 		    ((*flags & GPIOD_FLAGS_BIT_DIR_OUT) && (diff & GPIOD_FLAGS_BIT_DIR_VAL)))
694 			ret = -EINVAL;
695 		*flags = (*flags & ~mask) | (update & mask);
696 	}
697 	return ret;
698 }
699 
700 static int acpi_gpio_update_gpiod_flags(enum gpiod_flags *flags,
701 				        struct acpi_gpio_info *info)
702 {
703 	struct device *dev = &info->adev->dev;
704 	enum gpiod_flags old = *flags;
705 	int ret;
706 
707 	ret = __acpi_gpio_update_gpiod_flags(&old, info->flags);
708 	if (info->quirks & ACPI_GPIO_QUIRK_NO_IO_RESTRICTION) {
709 		if (ret)
710 			dev_warn(dev, FW_BUG "GPIO not in correct mode, fixing\n");
711 	} else {
712 		if (ret)
713 			dev_dbg(dev, "Override GPIO initialization flags\n");
714 		*flags = old;
715 	}
716 
717 	return ret;
718 }
719 
720 static int acpi_gpio_update_gpiod_lookup_flags(unsigned long *lookupflags,
721 					       struct acpi_gpio_info *info)
722 {
723 	switch (info->pin_config) {
724 	case ACPI_PIN_CONFIG_PULLUP:
725 		*lookupflags |= GPIO_PULL_UP;
726 		break;
727 	case ACPI_PIN_CONFIG_PULLDOWN:
728 		*lookupflags |= GPIO_PULL_DOWN;
729 		break;
730 	case ACPI_PIN_CONFIG_NOPULL:
731 		*lookupflags |= GPIO_PULL_DISABLE;
732 		break;
733 	default:
734 		break;
735 	}
736 
737 	if (info->polarity == GPIO_ACTIVE_LOW)
738 		*lookupflags |= GPIO_ACTIVE_LOW;
739 
740 	return 0;
741 }
742 
743 struct acpi_gpio_lookup {
744 	struct acpi_gpio_info info;
745 	int index;
746 	u16 pin_index;
747 	bool active_low;
748 	struct gpio_desc *desc;
749 	int n;
750 };
751 
752 static int acpi_populate_gpio_lookup(struct acpi_resource *ares, void *data)
753 {
754 	struct acpi_gpio_lookup *lookup = data;
755 
756 	if (ares->type != ACPI_RESOURCE_TYPE_GPIO)
757 		return 1;
758 
759 	if (!lookup->desc) {
760 		const struct acpi_resource_gpio *agpio = &ares->data.gpio;
761 		bool gpioint = agpio->connection_type == ACPI_RESOURCE_GPIO_TYPE_INT;
762 		struct gpio_desc *desc;
763 		u16 pin_index;
764 
765 		if (lookup->info.quirks & ACPI_GPIO_QUIRK_ONLY_GPIOIO && gpioint)
766 			lookup->index++;
767 
768 		if (lookup->n++ != lookup->index)
769 			return 1;
770 
771 		pin_index = lookup->pin_index;
772 		if (pin_index >= agpio->pin_table_length)
773 			return 1;
774 
775 		if (lookup->info.quirks & ACPI_GPIO_QUIRK_ABSOLUTE_NUMBER)
776 			desc = gpio_to_desc(agpio->pin_table[pin_index]);
777 		else
778 			desc = acpi_get_gpiod(agpio->resource_source.string_ptr,
779 					      agpio->pin_table[pin_index]);
780 		lookup->desc = desc;
781 		lookup->info.pin_config = agpio->pin_config;
782 		lookup->info.debounce = agpio->debounce_timeout;
783 		lookup->info.gpioint = gpioint;
784 		lookup->info.wake_capable = acpi_gpio_irq_is_wake(&lookup->info.adev->dev, agpio);
785 
786 		/*
787 		 * Polarity and triggering are only specified for GpioInt
788 		 * resource.
789 		 * Note: we expect here:
790 		 * - ACPI_ACTIVE_LOW == GPIO_ACTIVE_LOW
791 		 * - ACPI_ACTIVE_HIGH == GPIO_ACTIVE_HIGH
792 		 */
793 		if (lookup->info.gpioint) {
794 			lookup->info.polarity = agpio->polarity;
795 			lookup->info.triggering = agpio->triggering;
796 		} else {
797 			lookup->info.polarity = lookup->active_low;
798 		}
799 
800 		lookup->info.flags = acpi_gpio_to_gpiod_flags(agpio, lookup->info.polarity);
801 	}
802 
803 	return 1;
804 }
805 
806 static int acpi_gpio_resource_lookup(struct acpi_gpio_lookup *lookup,
807 				     struct acpi_gpio_info *info)
808 {
809 	struct acpi_device *adev = lookup->info.adev;
810 	struct list_head res_list;
811 	int ret;
812 
813 	INIT_LIST_HEAD(&res_list);
814 
815 	ret = acpi_dev_get_resources(adev, &res_list,
816 				     acpi_populate_gpio_lookup,
817 				     lookup);
818 	if (ret < 0)
819 		return ret;
820 
821 	acpi_dev_free_resource_list(&res_list);
822 
823 	if (!lookup->desc)
824 		return -ENOENT;
825 
826 	if (info)
827 		*info = lookup->info;
828 	return 0;
829 }
830 
831 static int acpi_gpio_property_lookup(struct fwnode_handle *fwnode,
832 				     const char *propname, int index,
833 				     struct acpi_gpio_lookup *lookup)
834 {
835 	struct fwnode_reference_args args;
836 	unsigned int quirks = 0;
837 	int ret;
838 
839 	memset(&args, 0, sizeof(args));
840 	ret = __acpi_node_get_property_reference(fwnode, propname, index, 3,
841 						 &args);
842 	if (ret) {
843 		struct acpi_device *adev = to_acpi_device_node(fwnode);
844 
845 		if (!adev)
846 			return ret;
847 
848 		if (!acpi_get_driver_gpio_data(adev, propname, index, &args,
849 					       &quirks))
850 			return ret;
851 	}
852 	/*
853 	 * The property was found and resolved, so need to lookup the GPIO based
854 	 * on returned args.
855 	 */
856 	if (!to_acpi_device_node(args.fwnode))
857 		return -EINVAL;
858 	if (args.nargs != 3)
859 		return -EPROTO;
860 
861 	lookup->index = args.args[0];
862 	lookup->pin_index = args.args[1];
863 	lookup->active_low = !!args.args[2];
864 
865 	lookup->info.adev = to_acpi_device_node(args.fwnode);
866 	lookup->info.quirks = quirks;
867 
868 	return 0;
869 }
870 
871 /**
872  * acpi_get_gpiod_by_index() - get a GPIO descriptor from device resources
873  * @adev: pointer to a ACPI device to get GPIO from
874  * @propname: Property name of the GPIO (optional)
875  * @index: index of GpioIo/GpioInt resource (starting from %0)
876  * @info: info pointer to fill in (optional)
877  *
878  * Function goes through ACPI resources for @adev and based on @index looks
879  * up a GpioIo/GpioInt resource, translates it to the Linux GPIO descriptor,
880  * and returns it. @index matches GpioIo/GpioInt resources only so if there
881  * are total %3 GPIO resources, the index goes from %0 to %2.
882  *
883  * If @propname is specified the GPIO is looked using device property. In
884  * that case @index is used to select the GPIO entry in the property value
885  * (in case of multiple).
886  *
887  * If the GPIO cannot be translated or there is an error, an ERR_PTR is
888  * returned.
889  *
890  * Note: if the GPIO resource has multiple entries in the pin list, this
891  * function only returns the first.
892  */
893 static struct gpio_desc *acpi_get_gpiod_by_index(struct acpi_device *adev,
894 						 const char *propname,
895 						 int index,
896 						 struct acpi_gpio_info *info)
897 {
898 	struct acpi_gpio_lookup lookup;
899 	int ret;
900 
901 	if (!adev)
902 		return ERR_PTR(-ENODEV);
903 
904 	memset(&lookup, 0, sizeof(lookup));
905 	lookup.index = index;
906 
907 	if (propname) {
908 		dev_dbg(&adev->dev, "GPIO: looking up %s\n", propname);
909 
910 		ret = acpi_gpio_property_lookup(acpi_fwnode_handle(adev),
911 						propname, index, &lookup);
912 		if (ret)
913 			return ERR_PTR(ret);
914 
915 		dev_dbg(&adev->dev, "GPIO: _DSD returned %s %d %u %u\n",
916 			dev_name(&lookup.info.adev->dev), lookup.index,
917 			lookup.pin_index, lookup.active_low);
918 	} else {
919 		dev_dbg(&adev->dev, "GPIO: looking up %d in _CRS\n", index);
920 		lookup.info.adev = adev;
921 	}
922 
923 	ret = acpi_gpio_resource_lookup(&lookup, info);
924 	return ret ? ERR_PTR(ret) : lookup.desc;
925 }
926 
927 /**
928  * acpi_get_gpiod_from_data() - get a GPIO descriptor from ACPI data node
929  * @fwnode: pointer to an ACPI firmware node to get the GPIO information from
930  * @propname: Property name of the GPIO
931  * @index: index of GpioIo/GpioInt resource (starting from %0)
932  * @info: info pointer to fill in (optional)
933  *
934  * This function uses the property-based GPIO lookup to get to the GPIO
935  * resource with the relevant information from a data-only ACPI firmware node
936  * and uses that to obtain the GPIO descriptor to return.
937  *
938  * If the GPIO cannot be translated or there is an error an ERR_PTR is
939  * returned.
940  */
941 static struct gpio_desc *acpi_get_gpiod_from_data(struct fwnode_handle *fwnode,
942 						  const char *propname,
943 						  int index,
944 						  struct acpi_gpio_info *info)
945 {
946 	struct acpi_gpio_lookup lookup;
947 	int ret;
948 
949 	if (!is_acpi_data_node(fwnode))
950 		return ERR_PTR(-ENODEV);
951 
952 	if (!propname)
953 		return ERR_PTR(-EINVAL);
954 
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, "NL5xRU"),
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 1.7.7
1637 		 */
1638 		.matches = {
1639 			DMI_MATCH(DMI_BOARD_NAME, "NH5xAx"),
1640 		},
1641 		.driver_data = &(struct acpi_gpiolib_dmi_quirk) {
1642 			.ignore_wake = "SYNA1202:00@16",
1643 		},
1644 	},
1645 	{} /* Terminating entry */
1646 };
1647 
1648 static int __init acpi_gpio_setup_params(void)
1649 {
1650 	const struct acpi_gpiolib_dmi_quirk *quirk = NULL;
1651 	const struct dmi_system_id *id;
1652 
1653 	id = dmi_first_match(gpiolib_acpi_quirks);
1654 	if (id)
1655 		quirk = id->driver_data;
1656 
1657 	if (run_edge_events_on_boot < 0) {
1658 		if (quirk && quirk->no_edge_events_on_boot)
1659 			run_edge_events_on_boot = 0;
1660 		else
1661 			run_edge_events_on_boot = 1;
1662 	}
1663 
1664 	if (ignore_wake == NULL && quirk && quirk->ignore_wake)
1665 		ignore_wake = quirk->ignore_wake;
1666 
1667 	if (ignore_interrupt == NULL && quirk && quirk->ignore_interrupt)
1668 		ignore_interrupt = quirk->ignore_interrupt;
1669 
1670 	return 0;
1671 }
1672 
1673 /* Directly after dmi_setup() which runs as core_initcall() */
1674 postcore_initcall(acpi_gpio_setup_params);
1675