xref: /openbmc/linux/drivers/gpio/gpiolib-acpi.c (revision 08b7cf13)
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 struct acpi_gpiolib_dmi_quirk {
36 	bool no_edge_events_on_boot;
37 	char *ignore_wake;
38 };
39 
40 /**
41  * struct acpi_gpio_event - ACPI GPIO event handler data
42  *
43  * @node:	  list-entry of the events list of the struct acpi_gpio_chip
44  * @handle:	  handle of ACPI method to execute when the IRQ triggers
45  * @handler:	  handler function to pass to request_irq() when requesting the IRQ
46  * @pin:	  GPIO pin number on the struct gpio_chip
47  * @irq:	  Linux IRQ number for the event, for request_irq() / free_irq()
48  * @irqflags:	  flags to pass to request_irq() when requesting the IRQ
49  * @irq_is_wake:  If the ACPI flags indicate the IRQ is a wakeup source
50  * @irq_requested:True if request_irq() has been done
51  * @desc:	  struct gpio_desc for the GPIO pin for this event
52  */
53 struct acpi_gpio_event {
54 	struct list_head node;
55 	acpi_handle handle;
56 	irq_handler_t handler;
57 	unsigned int pin;
58 	unsigned int irq;
59 	unsigned long irqflags;
60 	bool irq_is_wake;
61 	bool irq_requested;
62 	struct gpio_desc *desc;
63 };
64 
65 struct acpi_gpio_connection {
66 	struct list_head node;
67 	unsigned int pin;
68 	struct gpio_desc *desc;
69 };
70 
71 struct acpi_gpio_chip {
72 	/*
73 	 * ACPICA requires that the first field of the context parameter
74 	 * passed to acpi_install_address_space_handler() is large enough
75 	 * to hold struct acpi_connection_info.
76 	 */
77 	struct acpi_connection_info conn_info;
78 	struct list_head conns;
79 	struct mutex conn_lock;
80 	struct gpio_chip *chip;
81 	struct list_head events;
82 	struct list_head deferred_req_irqs_list_entry;
83 };
84 
85 /*
86  * For GPIO chips which call acpi_gpiochip_request_interrupts() before late_init
87  * (so builtin drivers) we register the ACPI GpioInt IRQ handlers from a
88  * late_initcall_sync() handler, so that other builtin drivers can register their
89  * OpRegions before the event handlers can run. This list contains GPIO chips
90  * for which the acpi_gpiochip_request_irqs() call has been deferred.
91  */
92 static DEFINE_MUTEX(acpi_gpio_deferred_req_irqs_lock);
93 static LIST_HEAD(acpi_gpio_deferred_req_irqs_list);
94 static bool acpi_gpio_deferred_req_irqs_done;
95 
96 static int acpi_gpiochip_find(struct gpio_chip *gc, void *data)
97 {
98 	return gc->parent && device_match_acpi_handle(gc->parent, data);
99 }
100 
101 /**
102  * acpi_get_gpiod() - Translate ACPI GPIO pin to GPIO descriptor usable with GPIO API
103  * @path:	ACPI GPIO controller full path name, (e.g. "\\_SB.GPO1")
104  * @pin:	ACPI GPIO pin number (0-based, controller-relative)
105  *
106  * Return: GPIO descriptor to use with Linux generic GPIO API, or ERR_PTR
107  * error value. Specifically returns %-EPROBE_DEFER if the referenced GPIO
108  * controller does not have GPIO chip registered at the moment. This is to
109  * support probe deferral.
110  */
111 static struct gpio_desc *acpi_get_gpiod(char *path, int pin)
112 {
113 	struct gpio_chip *chip;
114 	acpi_handle handle;
115 	acpi_status status;
116 
117 	status = acpi_get_handle(NULL, path, &handle);
118 	if (ACPI_FAILURE(status))
119 		return ERR_PTR(-ENODEV);
120 
121 	chip = gpiochip_find(handle, acpi_gpiochip_find);
122 	if (!chip)
123 		return ERR_PTR(-EPROBE_DEFER);
124 
125 	return gpiochip_get_desc(chip, pin);
126 }
127 
128 /**
129  * acpi_get_and_request_gpiod - Translate ACPI GPIO pin to GPIO descriptor and
130  *                              hold a refcount to the GPIO device.
131  * @path:      ACPI GPIO controller full path name, (e.g. "\\_SB.GPO1")
132  * @pin:       ACPI GPIO pin number (0-based, controller-relative)
133  * @label:     Label to pass to gpiod_request()
134  *
135  * This function is a simple pass-through to acpi_get_gpiod(), except that
136  * as it is intended for use outside of the GPIO layer (in a similar fashion to
137  * gpiod_get_index() for example) it also holds a reference to the GPIO device.
138  */
139 struct gpio_desc *acpi_get_and_request_gpiod(char *path, int pin, char *label)
140 {
141 	struct gpio_desc *gpio;
142 	int ret;
143 
144 	gpio = acpi_get_gpiod(path, pin);
145 	if (IS_ERR(gpio))
146 		return gpio;
147 
148 	ret = gpiod_request(gpio, label);
149 	if (ret)
150 		return ERR_PTR(ret);
151 
152 	return gpio;
153 }
154 EXPORT_SYMBOL_GPL(acpi_get_and_request_gpiod);
155 
156 static irqreturn_t acpi_gpio_irq_handler(int irq, void *data)
157 {
158 	struct acpi_gpio_event *event = data;
159 
160 	acpi_evaluate_object(event->handle, NULL, NULL, NULL);
161 
162 	return IRQ_HANDLED;
163 }
164 
165 static irqreturn_t acpi_gpio_irq_handler_evt(int irq, void *data)
166 {
167 	struct acpi_gpio_event *event = data;
168 
169 	acpi_execute_simple_method(event->handle, NULL, event->pin);
170 
171 	return IRQ_HANDLED;
172 }
173 
174 static void acpi_gpio_chip_dh(acpi_handle handle, void *data)
175 {
176 	/* The address of this function is used as a key. */
177 }
178 
179 bool acpi_gpio_get_irq_resource(struct acpi_resource *ares,
180 				struct acpi_resource_gpio **agpio)
181 {
182 	struct acpi_resource_gpio *gpio;
183 
184 	if (ares->type != ACPI_RESOURCE_TYPE_GPIO)
185 		return false;
186 
187 	gpio = &ares->data.gpio;
188 	if (gpio->connection_type != ACPI_RESOURCE_GPIO_TYPE_INT)
189 		return false;
190 
191 	*agpio = gpio;
192 	return true;
193 }
194 EXPORT_SYMBOL_GPL(acpi_gpio_get_irq_resource);
195 
196 /**
197  * acpi_gpio_get_io_resource - Fetch details of an ACPI resource if it is a GPIO
198  *			       I/O resource or return False if not.
199  * @ares:	Pointer to the ACPI resource to fetch
200  * @agpio:	Pointer to a &struct acpi_resource_gpio to store the output pointer
201  */
202 bool acpi_gpio_get_io_resource(struct acpi_resource *ares,
203 			       struct acpi_resource_gpio **agpio)
204 {
205 	struct acpi_resource_gpio *gpio;
206 
207 	if (ares->type != ACPI_RESOURCE_TYPE_GPIO)
208 		return false;
209 
210 	gpio = &ares->data.gpio;
211 	if (gpio->connection_type != ACPI_RESOURCE_GPIO_TYPE_IO)
212 		return false;
213 
214 	*agpio = gpio;
215 	return true;
216 }
217 EXPORT_SYMBOL_GPL(acpi_gpio_get_io_resource);
218 
219 static void acpi_gpiochip_request_irq(struct acpi_gpio_chip *acpi_gpio,
220 				      struct acpi_gpio_event *event)
221 {
222 	struct device *parent = acpi_gpio->chip->parent;
223 	int ret, value;
224 
225 	ret = request_threaded_irq(event->irq, NULL, event->handler,
226 				   event->irqflags | IRQF_ONESHOT, "ACPI:Event", event);
227 	if (ret) {
228 		dev_err(parent, "Failed to setup interrupt handler for %d\n", event->irq);
229 		return;
230 	}
231 
232 	if (event->irq_is_wake)
233 		enable_irq_wake(event->irq);
234 
235 	event->irq_requested = true;
236 
237 	/* Make sure we trigger the initial state of edge-triggered IRQs */
238 	if (run_edge_events_on_boot &&
239 	    (event->irqflags & (IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING))) {
240 		value = gpiod_get_raw_value_cansleep(event->desc);
241 		if (((event->irqflags & IRQF_TRIGGER_RISING) && value == 1) ||
242 		    ((event->irqflags & IRQF_TRIGGER_FALLING) && value == 0))
243 			event->handler(event->irq, event);
244 	}
245 }
246 
247 static void acpi_gpiochip_request_irqs(struct acpi_gpio_chip *acpi_gpio)
248 {
249 	struct acpi_gpio_event *event;
250 
251 	list_for_each_entry(event, &acpi_gpio->events, node)
252 		acpi_gpiochip_request_irq(acpi_gpio, event);
253 }
254 
255 static enum gpiod_flags
256 acpi_gpio_to_gpiod_flags(const struct acpi_resource_gpio *agpio, int polarity)
257 {
258 	/* GpioInt() implies input configuration */
259 	if (agpio->connection_type == ACPI_RESOURCE_GPIO_TYPE_INT)
260 		return GPIOD_IN;
261 
262 	switch (agpio->io_restriction) {
263 	case ACPI_IO_RESTRICT_INPUT:
264 		return GPIOD_IN;
265 	case ACPI_IO_RESTRICT_OUTPUT:
266 		/*
267 		 * ACPI GPIO resources don't contain an initial value for the
268 		 * GPIO. Therefore we deduce that value from the pull field
269 		 * and the polarity instead. If the pin is pulled up we assume
270 		 * default to be high, if it is pulled down we assume default
271 		 * to be low, otherwise we leave pin untouched. For active low
272 		 * polarity values will be switched. See also
273 		 * Documentation/firmware-guide/acpi/gpio-properties.rst.
274 		 */
275 		switch (agpio->pin_config) {
276 		case ACPI_PIN_CONFIG_PULLUP:
277 			return polarity == GPIO_ACTIVE_LOW ? GPIOD_OUT_LOW : GPIOD_OUT_HIGH;
278 		case ACPI_PIN_CONFIG_PULLDOWN:
279 			return polarity == GPIO_ACTIVE_LOW ? GPIOD_OUT_HIGH : GPIOD_OUT_LOW;
280 		default:
281 			break;
282 		}
283 		break;
284 	default:
285 		break;
286 	}
287 
288 	/*
289 	 * Assume that the BIOS has configured the direction and pull
290 	 * accordingly.
291 	 */
292 	return GPIOD_ASIS;
293 }
294 
295 static struct gpio_desc *acpi_request_own_gpiod(struct gpio_chip *chip,
296 						struct acpi_resource_gpio *agpio,
297 						unsigned int index,
298 						const char *label)
299 {
300 	int polarity = GPIO_ACTIVE_HIGH;
301 	enum gpiod_flags flags = acpi_gpio_to_gpiod_flags(agpio, polarity);
302 	unsigned int pin = agpio->pin_table[index];
303 	struct gpio_desc *desc;
304 	int ret;
305 
306 	desc = gpiochip_request_own_desc(chip, pin, label, polarity, flags);
307 	if (IS_ERR(desc))
308 		return desc;
309 
310 	/* ACPI uses hundredths of milliseconds units */
311 	ret = gpio_set_debounce_timeout(desc, agpio->debounce_timeout * 10);
312 	if (ret)
313 		dev_warn(chip->parent,
314 			 "Failed to set debounce-timeout for pin 0x%04X, err %d\n",
315 			 pin, ret);
316 
317 	return desc;
318 }
319 
320 static bool acpi_gpio_in_ignore_list(const char *controller_in, int pin_in)
321 {
322 	const char *controller, *pin_str;
323 	int len, pin;
324 	char *endp;
325 
326 	controller = ignore_wake;
327 	while (controller) {
328 		pin_str = strchr(controller, '@');
329 		if (!pin_str)
330 			goto err;
331 
332 		len = pin_str - controller;
333 		if (len == strlen(controller_in) &&
334 		    strncmp(controller, controller_in, len) == 0) {
335 			pin = simple_strtoul(pin_str + 1, &endp, 10);
336 			if (*endp != 0 && *endp != ',')
337 				goto err;
338 
339 			if (pin == pin_in)
340 				return true;
341 		}
342 
343 		controller = strchr(controller, ',');
344 		if (controller)
345 			controller++;
346 	}
347 
348 	return false;
349 err:
350 	pr_err_once("Error: Invalid value for gpiolib_acpi.ignore_wake: %s\n", ignore_wake);
351 	return false;
352 }
353 
354 static bool acpi_gpio_irq_is_wake(struct device *parent,
355 				  struct acpi_resource_gpio *agpio)
356 {
357 	int pin = agpio->pin_table[0];
358 
359 	if (agpio->wake_capable != ACPI_WAKE_CAPABLE)
360 		return false;
361 
362 	if (acpi_gpio_in_ignore_list(dev_name(parent), pin)) {
363 		dev_info(parent, "Ignoring wakeup on pin %d\n", pin);
364 		return false;
365 	}
366 
367 	return true;
368 }
369 
370 /* Always returns AE_OK so that we keep looping over the resources */
371 static acpi_status acpi_gpiochip_alloc_event(struct acpi_resource *ares,
372 					     void *context)
373 {
374 	struct acpi_gpio_chip *acpi_gpio = context;
375 	struct gpio_chip *chip = acpi_gpio->chip;
376 	struct acpi_resource_gpio *agpio;
377 	acpi_handle handle, evt_handle;
378 	struct acpi_gpio_event *event;
379 	irq_handler_t handler = NULL;
380 	struct gpio_desc *desc;
381 	int ret, pin, irq;
382 
383 	if (!acpi_gpio_get_irq_resource(ares, &agpio))
384 		return AE_OK;
385 
386 	handle = ACPI_HANDLE(chip->parent);
387 	pin = agpio->pin_table[0];
388 
389 	if (pin <= 255) {
390 		char ev_name[5];
391 		sprintf(ev_name, "_%c%02hhX",
392 			agpio->triggering == ACPI_EDGE_SENSITIVE ? 'E' : 'L',
393 			pin);
394 		if (ACPI_SUCCESS(acpi_get_handle(handle, ev_name, &evt_handle)))
395 			handler = acpi_gpio_irq_handler;
396 	}
397 	if (!handler) {
398 		if (ACPI_SUCCESS(acpi_get_handle(handle, "_EVT", &evt_handle)))
399 			handler = acpi_gpio_irq_handler_evt;
400 	}
401 	if (!handler)
402 		return AE_OK;
403 
404 	desc = acpi_request_own_gpiod(chip, agpio, 0, "ACPI:Event");
405 	if (IS_ERR(desc)) {
406 		dev_err(chip->parent,
407 			"Failed to request GPIO for pin 0x%04X, err %ld\n",
408 			pin, PTR_ERR(desc));
409 		return AE_OK;
410 	}
411 
412 	ret = gpiochip_lock_as_irq(chip, pin);
413 	if (ret) {
414 		dev_err(chip->parent,
415 			"Failed to lock GPIO pin 0x%04X as interrupt, err %d\n",
416 			pin, ret);
417 		goto fail_free_desc;
418 	}
419 
420 	irq = gpiod_to_irq(desc);
421 	if (irq < 0) {
422 		dev_err(chip->parent,
423 			"Failed to translate GPIO pin 0x%04X to IRQ, err %d\n",
424 			pin, irq);
425 		goto fail_unlock_irq;
426 	}
427 
428 	event = kzalloc(sizeof(*event), GFP_KERNEL);
429 	if (!event)
430 		goto fail_unlock_irq;
431 
432 	event->irqflags = IRQF_ONESHOT;
433 	if (agpio->triggering == ACPI_LEVEL_SENSITIVE) {
434 		if (agpio->polarity == ACPI_ACTIVE_HIGH)
435 			event->irqflags |= IRQF_TRIGGER_HIGH;
436 		else
437 			event->irqflags |= IRQF_TRIGGER_LOW;
438 	} else {
439 		switch (agpio->polarity) {
440 		case ACPI_ACTIVE_HIGH:
441 			event->irqflags |= IRQF_TRIGGER_RISING;
442 			break;
443 		case ACPI_ACTIVE_LOW:
444 			event->irqflags |= IRQF_TRIGGER_FALLING;
445 			break;
446 		default:
447 			event->irqflags |= IRQF_TRIGGER_RISING |
448 					   IRQF_TRIGGER_FALLING;
449 			break;
450 		}
451 	}
452 
453 	event->handle = evt_handle;
454 	event->handler = handler;
455 	event->irq = irq;
456 	event->irq_is_wake = acpi_gpio_irq_is_wake(chip->parent, agpio);
457 	event->pin = pin;
458 	event->desc = desc;
459 
460 	list_add_tail(&event->node, &acpi_gpio->events);
461 
462 	return AE_OK;
463 
464 fail_unlock_irq:
465 	gpiochip_unlock_as_irq(chip, pin);
466 fail_free_desc:
467 	gpiochip_free_own_desc(desc);
468 
469 	return AE_OK;
470 }
471 
472 /**
473  * acpi_gpiochip_request_interrupts() - Register isr for gpio chip ACPI events
474  * @chip:      GPIO chip
475  *
476  * ACPI5 platforms can use GPIO signaled ACPI events. These GPIO interrupts are
477  * handled by ACPI event methods which need to be called from the GPIO
478  * chip's interrupt handler. acpi_gpiochip_request_interrupts() finds out which
479  * GPIO pins have ACPI event methods and assigns interrupt handlers that calls
480  * the ACPI event methods for those pins.
481  */
482 void acpi_gpiochip_request_interrupts(struct gpio_chip *chip)
483 {
484 	struct acpi_gpio_chip *acpi_gpio;
485 	acpi_handle handle;
486 	acpi_status status;
487 	bool defer;
488 
489 	if (!chip->parent || !chip->to_irq)
490 		return;
491 
492 	handle = ACPI_HANDLE(chip->parent);
493 	if (!handle)
494 		return;
495 
496 	status = acpi_get_data(handle, acpi_gpio_chip_dh, (void **)&acpi_gpio);
497 	if (ACPI_FAILURE(status))
498 		return;
499 
500 	acpi_walk_resources(handle, "_AEI",
501 			    acpi_gpiochip_alloc_event, acpi_gpio);
502 
503 	mutex_lock(&acpi_gpio_deferred_req_irqs_lock);
504 	defer = !acpi_gpio_deferred_req_irqs_done;
505 	if (defer)
506 		list_add(&acpi_gpio->deferred_req_irqs_list_entry,
507 			 &acpi_gpio_deferred_req_irqs_list);
508 	mutex_unlock(&acpi_gpio_deferred_req_irqs_lock);
509 
510 	if (defer)
511 		return;
512 
513 	acpi_gpiochip_request_irqs(acpi_gpio);
514 }
515 EXPORT_SYMBOL_GPL(acpi_gpiochip_request_interrupts);
516 
517 /**
518  * acpi_gpiochip_free_interrupts() - Free GPIO ACPI event interrupts.
519  * @chip:      GPIO chip
520  *
521  * Free interrupts associated with GPIO ACPI event method for the given
522  * GPIO chip.
523  */
524 void acpi_gpiochip_free_interrupts(struct gpio_chip *chip)
525 {
526 	struct acpi_gpio_chip *acpi_gpio;
527 	struct acpi_gpio_event *event, *ep;
528 	acpi_handle handle;
529 	acpi_status status;
530 
531 	if (!chip->parent || !chip->to_irq)
532 		return;
533 
534 	handle = ACPI_HANDLE(chip->parent);
535 	if (!handle)
536 		return;
537 
538 	status = acpi_get_data(handle, acpi_gpio_chip_dh, (void **)&acpi_gpio);
539 	if (ACPI_FAILURE(status))
540 		return;
541 
542 	mutex_lock(&acpi_gpio_deferred_req_irqs_lock);
543 	if (!list_empty(&acpi_gpio->deferred_req_irqs_list_entry))
544 		list_del_init(&acpi_gpio->deferred_req_irqs_list_entry);
545 	mutex_unlock(&acpi_gpio_deferred_req_irqs_lock);
546 
547 	list_for_each_entry_safe_reverse(event, ep, &acpi_gpio->events, node) {
548 		if (event->irq_requested) {
549 			if (event->irq_is_wake)
550 				disable_irq_wake(event->irq);
551 
552 			free_irq(event->irq, event);
553 		}
554 
555 		gpiochip_unlock_as_irq(chip, event->pin);
556 		gpiochip_free_own_desc(event->desc);
557 		list_del(&event->node);
558 		kfree(event);
559 	}
560 }
561 EXPORT_SYMBOL_GPL(acpi_gpiochip_free_interrupts);
562 
563 int acpi_dev_add_driver_gpios(struct acpi_device *adev,
564 			      const struct acpi_gpio_mapping *gpios)
565 {
566 	if (adev && gpios) {
567 		adev->driver_gpios = gpios;
568 		return 0;
569 	}
570 	return -EINVAL;
571 }
572 EXPORT_SYMBOL_GPL(acpi_dev_add_driver_gpios);
573 
574 void acpi_dev_remove_driver_gpios(struct acpi_device *adev)
575 {
576 	if (adev)
577 		adev->driver_gpios = NULL;
578 }
579 EXPORT_SYMBOL_GPL(acpi_dev_remove_driver_gpios);
580 
581 static void acpi_dev_release_driver_gpios(void *adev)
582 {
583 	acpi_dev_remove_driver_gpios(adev);
584 }
585 
586 int devm_acpi_dev_add_driver_gpios(struct device *dev,
587 				   const struct acpi_gpio_mapping *gpios)
588 {
589 	struct acpi_device *adev = ACPI_COMPANION(dev);
590 	int ret;
591 
592 	ret = acpi_dev_add_driver_gpios(adev, gpios);
593 	if (ret)
594 		return ret;
595 
596 	return devm_add_action_or_reset(dev, acpi_dev_release_driver_gpios, adev);
597 }
598 EXPORT_SYMBOL_GPL(devm_acpi_dev_add_driver_gpios);
599 
600 static bool acpi_get_driver_gpio_data(struct acpi_device *adev,
601 				      const char *name, int index,
602 				      struct fwnode_reference_args *args,
603 				      unsigned int *quirks)
604 {
605 	const struct acpi_gpio_mapping *gm;
606 
607 	if (!adev->driver_gpios)
608 		return false;
609 
610 	for (gm = adev->driver_gpios; gm->name; gm++)
611 		if (!strcmp(name, gm->name) && gm->data && index < gm->size) {
612 			const struct acpi_gpio_params *par = gm->data + index;
613 
614 			args->fwnode = acpi_fwnode_handle(adev);
615 			args->args[0] = par->crs_entry_index;
616 			args->args[1] = par->line_index;
617 			args->args[2] = par->active_low;
618 			args->nargs = 3;
619 
620 			*quirks = gm->quirks;
621 			return true;
622 		}
623 
624 	return false;
625 }
626 
627 static int
628 __acpi_gpio_update_gpiod_flags(enum gpiod_flags *flags, enum gpiod_flags update)
629 {
630 	const enum gpiod_flags mask =
631 		GPIOD_FLAGS_BIT_DIR_SET | GPIOD_FLAGS_BIT_DIR_OUT |
632 		GPIOD_FLAGS_BIT_DIR_VAL;
633 	int ret = 0;
634 
635 	/*
636 	 * Check if the BIOS has IoRestriction with explicitly set direction
637 	 * and update @flags accordingly. Otherwise use whatever caller asked
638 	 * for.
639 	 */
640 	if (update & GPIOD_FLAGS_BIT_DIR_SET) {
641 		enum gpiod_flags diff = *flags ^ update;
642 
643 		/*
644 		 * Check if caller supplied incompatible GPIO initialization
645 		 * flags.
646 		 *
647 		 * Return %-EINVAL to notify that firmware has different
648 		 * settings and we are going to use them.
649 		 */
650 		if (((*flags & GPIOD_FLAGS_BIT_DIR_SET) && (diff & GPIOD_FLAGS_BIT_DIR_OUT)) ||
651 		    ((*flags & GPIOD_FLAGS_BIT_DIR_OUT) && (diff & GPIOD_FLAGS_BIT_DIR_VAL)))
652 			ret = -EINVAL;
653 		*flags = (*flags & ~mask) | (update & mask);
654 	}
655 	return ret;
656 }
657 
658 int
659 acpi_gpio_update_gpiod_flags(enum gpiod_flags *flags, struct acpi_gpio_info *info)
660 {
661 	struct device *dev = &info->adev->dev;
662 	enum gpiod_flags old = *flags;
663 	int ret;
664 
665 	ret = __acpi_gpio_update_gpiod_flags(&old, info->flags);
666 	if (info->quirks & ACPI_GPIO_QUIRK_NO_IO_RESTRICTION) {
667 		if (ret)
668 			dev_warn(dev, FW_BUG "GPIO not in correct mode, fixing\n");
669 	} else {
670 		if (ret)
671 			dev_dbg(dev, "Override GPIO initialization flags\n");
672 		*flags = old;
673 	}
674 
675 	return ret;
676 }
677 
678 int acpi_gpio_update_gpiod_lookup_flags(unsigned long *lookupflags,
679 					struct acpi_gpio_info *info)
680 {
681 	switch (info->pin_config) {
682 	case ACPI_PIN_CONFIG_PULLUP:
683 		*lookupflags |= GPIO_PULL_UP;
684 		break;
685 	case ACPI_PIN_CONFIG_PULLDOWN:
686 		*lookupflags |= GPIO_PULL_DOWN;
687 		break;
688 	default:
689 		break;
690 	}
691 
692 	if (info->polarity == GPIO_ACTIVE_LOW)
693 		*lookupflags |= GPIO_ACTIVE_LOW;
694 
695 	return 0;
696 }
697 
698 struct acpi_gpio_lookup {
699 	struct acpi_gpio_info info;
700 	int index;
701 	u16 pin_index;
702 	bool active_low;
703 	struct gpio_desc *desc;
704 	int n;
705 };
706 
707 static int acpi_populate_gpio_lookup(struct acpi_resource *ares, void *data)
708 {
709 	struct acpi_gpio_lookup *lookup = data;
710 
711 	if (ares->type != ACPI_RESOURCE_TYPE_GPIO)
712 		return 1;
713 
714 	if (!lookup->desc) {
715 		const struct acpi_resource_gpio *agpio = &ares->data.gpio;
716 		bool gpioint = agpio->connection_type == ACPI_RESOURCE_GPIO_TYPE_INT;
717 		struct gpio_desc *desc;
718 		u16 pin_index;
719 
720 		if (lookup->info.quirks & ACPI_GPIO_QUIRK_ONLY_GPIOIO && gpioint)
721 			lookup->index++;
722 
723 		if (lookup->n++ != lookup->index)
724 			return 1;
725 
726 		pin_index = lookup->pin_index;
727 		if (pin_index >= agpio->pin_table_length)
728 			return 1;
729 
730 		if (lookup->info.quirks & ACPI_GPIO_QUIRK_ABSOLUTE_NUMBER)
731 			desc = gpio_to_desc(agpio->pin_table[pin_index]);
732 		else
733 			desc = acpi_get_gpiod(agpio->resource_source.string_ptr,
734 					      agpio->pin_table[pin_index]);
735 		lookup->desc = desc;
736 		lookup->info.pin_config = agpio->pin_config;
737 		lookup->info.debounce = agpio->debounce_timeout;
738 		lookup->info.gpioint = gpioint;
739 
740 		/*
741 		 * Polarity and triggering are only specified for GpioInt
742 		 * resource.
743 		 * Note: we expect here:
744 		 * - ACPI_ACTIVE_LOW == GPIO_ACTIVE_LOW
745 		 * - ACPI_ACTIVE_HIGH == GPIO_ACTIVE_HIGH
746 		 */
747 		if (lookup->info.gpioint) {
748 			lookup->info.polarity = agpio->polarity;
749 			lookup->info.triggering = agpio->triggering;
750 		} else {
751 			lookup->info.polarity = lookup->active_low;
752 		}
753 
754 		lookup->info.flags = acpi_gpio_to_gpiod_flags(agpio, lookup->info.polarity);
755 	}
756 
757 	return 1;
758 }
759 
760 static int acpi_gpio_resource_lookup(struct acpi_gpio_lookup *lookup,
761 				     struct acpi_gpio_info *info)
762 {
763 	struct acpi_device *adev = lookup->info.adev;
764 	struct list_head res_list;
765 	int ret;
766 
767 	INIT_LIST_HEAD(&res_list);
768 
769 	ret = acpi_dev_get_resources(adev, &res_list,
770 				     acpi_populate_gpio_lookup,
771 				     lookup);
772 	if (ret < 0)
773 		return ret;
774 
775 	acpi_dev_free_resource_list(&res_list);
776 
777 	if (!lookup->desc)
778 		return -ENOENT;
779 
780 	if (info)
781 		*info = lookup->info;
782 	return 0;
783 }
784 
785 static int acpi_gpio_property_lookup(struct fwnode_handle *fwnode,
786 				     const char *propname, int index,
787 				     struct acpi_gpio_lookup *lookup)
788 {
789 	struct fwnode_reference_args args;
790 	unsigned int quirks = 0;
791 	int ret;
792 
793 	memset(&args, 0, sizeof(args));
794 	ret = __acpi_node_get_property_reference(fwnode, propname, index, 3,
795 						 &args);
796 	if (ret) {
797 		struct acpi_device *adev = to_acpi_device_node(fwnode);
798 
799 		if (!adev)
800 			return ret;
801 
802 		if (!acpi_get_driver_gpio_data(adev, propname, index, &args,
803 					       &quirks))
804 			return ret;
805 	}
806 	/*
807 	 * The property was found and resolved, so need to lookup the GPIO based
808 	 * on returned args.
809 	 */
810 	if (!to_acpi_device_node(args.fwnode))
811 		return -EINVAL;
812 	if (args.nargs != 3)
813 		return -EPROTO;
814 
815 	lookup->index = args.args[0];
816 	lookup->pin_index = args.args[1];
817 	lookup->active_low = !!args.args[2];
818 
819 	lookup->info.adev = to_acpi_device_node(args.fwnode);
820 	lookup->info.quirks = quirks;
821 
822 	return 0;
823 }
824 
825 /**
826  * acpi_get_gpiod_by_index() - get a GPIO descriptor from device resources
827  * @adev: pointer to a ACPI device to get GPIO from
828  * @propname: Property name of the GPIO (optional)
829  * @index: index of GpioIo/GpioInt resource (starting from %0)
830  * @info: info pointer to fill in (optional)
831  *
832  * Function goes through ACPI resources for @adev and based on @index looks
833  * up a GpioIo/GpioInt resource, translates it to the Linux GPIO descriptor,
834  * and returns it. @index matches GpioIo/GpioInt resources only so if there
835  * are total %3 GPIO resources, the index goes from %0 to %2.
836  *
837  * If @propname is specified the GPIO is looked using device property. In
838  * that case @index is used to select the GPIO entry in the property value
839  * (in case of multiple).
840  *
841  * If the GPIO cannot be translated or there is an error, an ERR_PTR is
842  * returned.
843  *
844  * Note: if the GPIO resource has multiple entries in the pin list, this
845  * function only returns the first.
846  */
847 static struct gpio_desc *acpi_get_gpiod_by_index(struct acpi_device *adev,
848 					  const char *propname, int index,
849 					  struct acpi_gpio_info *info)
850 {
851 	struct acpi_gpio_lookup lookup;
852 	int ret;
853 
854 	if (!adev)
855 		return ERR_PTR(-ENODEV);
856 
857 	memset(&lookup, 0, sizeof(lookup));
858 	lookup.index = index;
859 
860 	if (propname) {
861 		dev_dbg(&adev->dev, "GPIO: looking up %s\n", propname);
862 
863 		ret = acpi_gpio_property_lookup(acpi_fwnode_handle(adev),
864 						propname, index, &lookup);
865 		if (ret)
866 			return ERR_PTR(ret);
867 
868 		dev_dbg(&adev->dev, "GPIO: _DSD returned %s %d %u %u\n",
869 			dev_name(&lookup.info.adev->dev), lookup.index,
870 			lookup.pin_index, lookup.active_low);
871 	} else {
872 		dev_dbg(&adev->dev, "GPIO: looking up %d in _CRS\n", index);
873 		lookup.info.adev = adev;
874 	}
875 
876 	ret = acpi_gpio_resource_lookup(&lookup, info);
877 	return ret ? ERR_PTR(ret) : lookup.desc;
878 }
879 
880 static bool acpi_can_fallback_to_crs(struct acpi_device *adev,
881 				     const char *con_id)
882 {
883 	/* Never allow fallback if the device has properties */
884 	if (acpi_dev_has_props(adev) || adev->driver_gpios)
885 		return false;
886 
887 	return con_id == NULL;
888 }
889 
890 struct gpio_desc *acpi_find_gpio(struct device *dev,
891 				 const char *con_id,
892 				 unsigned int idx,
893 				 enum gpiod_flags *dflags,
894 				 unsigned long *lookupflags)
895 {
896 	struct acpi_device *adev = ACPI_COMPANION(dev);
897 	struct acpi_gpio_info info;
898 	struct gpio_desc *desc;
899 	char propname[32];
900 	int i;
901 
902 	/* Try first from _DSD */
903 	for (i = 0; i < ARRAY_SIZE(gpio_suffixes); i++) {
904 		if (con_id) {
905 			snprintf(propname, sizeof(propname), "%s-%s",
906 				 con_id, gpio_suffixes[i]);
907 		} else {
908 			snprintf(propname, sizeof(propname), "%s",
909 				 gpio_suffixes[i]);
910 		}
911 
912 		desc = acpi_get_gpiod_by_index(adev, propname, idx, &info);
913 		if (!IS_ERR(desc))
914 			break;
915 		if (PTR_ERR(desc) == -EPROBE_DEFER)
916 			return ERR_CAST(desc);
917 	}
918 
919 	/* Then from plain _CRS GPIOs */
920 	if (IS_ERR(desc)) {
921 		if (!acpi_can_fallback_to_crs(adev, con_id))
922 			return ERR_PTR(-ENOENT);
923 
924 		desc = acpi_get_gpiod_by_index(adev, NULL, idx, &info);
925 		if (IS_ERR(desc))
926 			return desc;
927 	}
928 
929 	if (info.gpioint &&
930 	    (*dflags == GPIOD_OUT_LOW || *dflags == GPIOD_OUT_HIGH)) {
931 		dev_dbg(&adev->dev, "refusing GpioInt() entry when doing GPIOD_OUT_* lookup\n");
932 		return ERR_PTR(-ENOENT);
933 	}
934 
935 	acpi_gpio_update_gpiod_flags(dflags, &info);
936 	acpi_gpio_update_gpiod_lookup_flags(lookupflags, &info);
937 	return desc;
938 }
939 
940 /**
941  * acpi_node_get_gpiod() - get a GPIO descriptor from ACPI resources
942  * @fwnode: pointer to an ACPI firmware node to get the GPIO information from
943  * @propname: Property name of the GPIO
944  * @index: index of GpioIo/GpioInt resource (starting from %0)
945  * @info: info pointer to fill in (optional)
946  *
947  * If @fwnode is an ACPI device object, call acpi_get_gpiod_by_index() for it.
948  * Otherwise (i.e. it is a data-only non-device object), use the property-based
949  * GPIO lookup to get to the GPIO resource with the relevant information and use
950  * that to obtain the GPIO descriptor to return.
951  *
952  * If the GPIO cannot be translated or there is an error an ERR_PTR is
953  * returned.
954  */
955 struct gpio_desc *acpi_node_get_gpiod(struct fwnode_handle *fwnode,
956 				      const char *propname, int index,
957 				      struct acpi_gpio_info *info)
958 {
959 	struct acpi_gpio_lookup lookup;
960 	struct acpi_device *adev;
961 	int ret;
962 
963 	adev = to_acpi_device_node(fwnode);
964 	if (adev)
965 		return acpi_get_gpiod_by_index(adev, propname, index, info);
966 
967 	if (!is_acpi_data_node(fwnode))
968 		return ERR_PTR(-ENODEV);
969 
970 	if (!propname)
971 		return ERR_PTR(-EINVAL);
972 
973 	memset(&lookup, 0, sizeof(lookup));
974 	lookup.index = index;
975 
976 	ret = acpi_gpio_property_lookup(fwnode, propname, index, &lookup);
977 	if (ret)
978 		return ERR_PTR(ret);
979 
980 	ret = acpi_gpio_resource_lookup(&lookup, info);
981 	return ret ? ERR_PTR(ret) : lookup.desc;
982 }
983 
984 /**
985  * acpi_dev_gpio_irq_get_by() - Find GpioInt and translate it to Linux IRQ number
986  * @adev: pointer to a ACPI device to get IRQ from
987  * @name: optional name of GpioInt resource
988  * @index: index of GpioInt resource (starting from %0)
989  *
990  * If the device has one or more GpioInt resources, this function can be
991  * used to translate from the GPIO offset in the resource to the Linux IRQ
992  * number.
993  *
994  * The function is idempotent, though each time it runs it will configure GPIO
995  * pin direction according to the flags in GpioInt resource.
996  *
997  * The function takes optional @name parameter. If the resource has a property
998  * name, then only those will be taken into account.
999  *
1000  * Return: Linux IRQ number (> %0) on success, negative errno on failure.
1001  */
1002 int acpi_dev_gpio_irq_get_by(struct acpi_device *adev, const char *name, int index)
1003 {
1004 	int idx, i;
1005 	unsigned int irq_flags;
1006 	int ret;
1007 
1008 	for (i = 0, idx = 0; idx <= index; i++) {
1009 		struct acpi_gpio_info info;
1010 		struct gpio_desc *desc;
1011 
1012 		desc = acpi_get_gpiod_by_index(adev, name, i, &info);
1013 
1014 		/* Ignore -EPROBE_DEFER, it only matters if idx matches */
1015 		if (IS_ERR(desc) && PTR_ERR(desc) != -EPROBE_DEFER)
1016 			return PTR_ERR(desc);
1017 
1018 		if (info.gpioint && idx++ == index) {
1019 			unsigned long lflags = GPIO_LOOKUP_FLAGS_DEFAULT;
1020 			enum gpiod_flags dflags = GPIOD_ASIS;
1021 			char label[32];
1022 			int irq;
1023 
1024 			if (IS_ERR(desc))
1025 				return PTR_ERR(desc);
1026 
1027 			irq = gpiod_to_irq(desc);
1028 			if (irq < 0)
1029 				return irq;
1030 
1031 			acpi_gpio_update_gpiod_flags(&dflags, &info);
1032 			acpi_gpio_update_gpiod_lookup_flags(&lflags, &info);
1033 
1034 			snprintf(label, sizeof(label), "GpioInt() %d", index);
1035 			ret = gpiod_configure_flags(desc, label, lflags, dflags);
1036 			if (ret < 0)
1037 				return ret;
1038 
1039 			/* ACPI uses hundredths of milliseconds units */
1040 			ret = gpio_set_debounce_timeout(desc, info.debounce * 10);
1041 			if (ret)
1042 				return ret;
1043 
1044 			irq_flags = acpi_dev_get_irq_type(info.triggering,
1045 							  info.polarity);
1046 
1047 			/*
1048 			 * If the IRQ is not already in use then set type
1049 			 * if specified and different than the current one.
1050 			 */
1051 			if (can_request_irq(irq, irq_flags)) {
1052 				if (irq_flags != IRQ_TYPE_NONE &&
1053 				    irq_flags != irq_get_trigger_type(irq))
1054 					irq_set_irq_type(irq, irq_flags);
1055 			} else {
1056 				dev_dbg(&adev->dev, "IRQ %d already in use\n", irq);
1057 			}
1058 
1059 			return irq;
1060 		}
1061 
1062 	}
1063 	return -ENOENT;
1064 }
1065 EXPORT_SYMBOL_GPL(acpi_dev_gpio_irq_get_by);
1066 
1067 static acpi_status
1068 acpi_gpio_adr_space_handler(u32 function, acpi_physical_address address,
1069 			    u32 bits, u64 *value, void *handler_context,
1070 			    void *region_context)
1071 {
1072 	struct acpi_gpio_chip *achip = region_context;
1073 	struct gpio_chip *chip = achip->chip;
1074 	struct acpi_resource_gpio *agpio;
1075 	struct acpi_resource *ares;
1076 	u16 pin_index = address;
1077 	acpi_status status;
1078 	int length;
1079 	int i;
1080 
1081 	status = acpi_buffer_to_resource(achip->conn_info.connection,
1082 					 achip->conn_info.length, &ares);
1083 	if (ACPI_FAILURE(status))
1084 		return status;
1085 
1086 	if (WARN_ON(ares->type != ACPI_RESOURCE_TYPE_GPIO)) {
1087 		ACPI_FREE(ares);
1088 		return AE_BAD_PARAMETER;
1089 	}
1090 
1091 	agpio = &ares->data.gpio;
1092 
1093 	if (WARN_ON(agpio->io_restriction == ACPI_IO_RESTRICT_INPUT &&
1094 	    function == ACPI_WRITE)) {
1095 		ACPI_FREE(ares);
1096 		return AE_BAD_PARAMETER;
1097 	}
1098 
1099 	length = min_t(u16, agpio->pin_table_length, pin_index + bits);
1100 	for (i = pin_index; i < length; ++i) {
1101 		int pin = agpio->pin_table[i];
1102 		struct acpi_gpio_connection *conn;
1103 		struct gpio_desc *desc;
1104 		bool found;
1105 
1106 		mutex_lock(&achip->conn_lock);
1107 
1108 		found = false;
1109 		list_for_each_entry(conn, &achip->conns, node) {
1110 			if (conn->pin == pin) {
1111 				found = true;
1112 				desc = conn->desc;
1113 				break;
1114 			}
1115 		}
1116 
1117 		/*
1118 		 * The same GPIO can be shared between operation region and
1119 		 * event but only if the access here is ACPI_READ. In that
1120 		 * case we "borrow" the event GPIO instead.
1121 		 */
1122 		if (!found && agpio->shareable == ACPI_SHARED &&
1123 		     function == ACPI_READ) {
1124 			struct acpi_gpio_event *event;
1125 
1126 			list_for_each_entry(event, &achip->events, node) {
1127 				if (event->pin == pin) {
1128 					desc = event->desc;
1129 					found = true;
1130 					break;
1131 				}
1132 			}
1133 		}
1134 
1135 		if (!found) {
1136 			desc = acpi_request_own_gpiod(chip, agpio, i, "ACPI:OpRegion");
1137 			if (IS_ERR(desc)) {
1138 				mutex_unlock(&achip->conn_lock);
1139 				status = AE_ERROR;
1140 				goto out;
1141 			}
1142 
1143 			conn = kzalloc(sizeof(*conn), GFP_KERNEL);
1144 			if (!conn) {
1145 				gpiochip_free_own_desc(desc);
1146 				mutex_unlock(&achip->conn_lock);
1147 				status = AE_NO_MEMORY;
1148 				goto out;
1149 			}
1150 
1151 			conn->pin = pin;
1152 			conn->desc = desc;
1153 			list_add_tail(&conn->node, &achip->conns);
1154 		}
1155 
1156 		mutex_unlock(&achip->conn_lock);
1157 
1158 		if (function == ACPI_WRITE)
1159 			gpiod_set_raw_value_cansleep(desc, !!(*value & BIT(i)));
1160 		else
1161 			*value |= (u64)gpiod_get_raw_value_cansleep(desc) << i;
1162 	}
1163 
1164 out:
1165 	ACPI_FREE(ares);
1166 	return status;
1167 }
1168 
1169 static void acpi_gpiochip_request_regions(struct acpi_gpio_chip *achip)
1170 {
1171 	struct gpio_chip *chip = achip->chip;
1172 	acpi_handle handle = ACPI_HANDLE(chip->parent);
1173 	acpi_status status;
1174 
1175 	INIT_LIST_HEAD(&achip->conns);
1176 	mutex_init(&achip->conn_lock);
1177 	status = acpi_install_address_space_handler(handle, ACPI_ADR_SPACE_GPIO,
1178 						    acpi_gpio_adr_space_handler,
1179 						    NULL, achip);
1180 	if (ACPI_FAILURE(status))
1181 		dev_err(chip->parent,
1182 		        "Failed to install GPIO OpRegion handler\n");
1183 }
1184 
1185 static void acpi_gpiochip_free_regions(struct acpi_gpio_chip *achip)
1186 {
1187 	struct gpio_chip *chip = achip->chip;
1188 	acpi_handle handle = ACPI_HANDLE(chip->parent);
1189 	struct acpi_gpio_connection *conn, *tmp;
1190 	acpi_status status;
1191 
1192 	status = acpi_remove_address_space_handler(handle, ACPI_ADR_SPACE_GPIO,
1193 						   acpi_gpio_adr_space_handler);
1194 	if (ACPI_FAILURE(status)) {
1195 		dev_err(chip->parent,
1196 			"Failed to remove GPIO OpRegion handler\n");
1197 		return;
1198 	}
1199 
1200 	list_for_each_entry_safe_reverse(conn, tmp, &achip->conns, node) {
1201 		gpiochip_free_own_desc(conn->desc);
1202 		list_del(&conn->node);
1203 		kfree(conn);
1204 	}
1205 }
1206 
1207 static struct gpio_desc *
1208 acpi_gpiochip_parse_own_gpio(struct acpi_gpio_chip *achip,
1209 			     struct fwnode_handle *fwnode,
1210 			     const char **name,
1211 			     unsigned long *lflags,
1212 			     enum gpiod_flags *dflags)
1213 {
1214 	struct gpio_chip *chip = achip->chip;
1215 	struct gpio_desc *desc;
1216 	u32 gpios[2];
1217 	int ret;
1218 
1219 	*lflags = GPIO_LOOKUP_FLAGS_DEFAULT;
1220 	*dflags = GPIOD_ASIS;
1221 	*name = NULL;
1222 
1223 	ret = fwnode_property_read_u32_array(fwnode, "gpios", gpios,
1224 					     ARRAY_SIZE(gpios));
1225 	if (ret < 0)
1226 		return ERR_PTR(ret);
1227 
1228 	desc = gpiochip_get_desc(chip, gpios[0]);
1229 	if (IS_ERR(desc))
1230 		return desc;
1231 
1232 	if (gpios[1])
1233 		*lflags |= GPIO_ACTIVE_LOW;
1234 
1235 	if (fwnode_property_present(fwnode, "input"))
1236 		*dflags |= GPIOD_IN;
1237 	else if (fwnode_property_present(fwnode, "output-low"))
1238 		*dflags |= GPIOD_OUT_LOW;
1239 	else if (fwnode_property_present(fwnode, "output-high"))
1240 		*dflags |= GPIOD_OUT_HIGH;
1241 	else
1242 		return ERR_PTR(-EINVAL);
1243 
1244 	fwnode_property_read_string(fwnode, "line-name", name);
1245 
1246 	return desc;
1247 }
1248 
1249 static void acpi_gpiochip_scan_gpios(struct acpi_gpio_chip *achip)
1250 {
1251 	struct gpio_chip *chip = achip->chip;
1252 	struct fwnode_handle *fwnode;
1253 
1254 	device_for_each_child_node(chip->parent, fwnode) {
1255 		unsigned long lflags;
1256 		enum gpiod_flags dflags;
1257 		struct gpio_desc *desc;
1258 		const char *name;
1259 		int ret;
1260 
1261 		if (!fwnode_property_present(fwnode, "gpio-hog"))
1262 			continue;
1263 
1264 		desc = acpi_gpiochip_parse_own_gpio(achip, fwnode, &name,
1265 						    &lflags, &dflags);
1266 		if (IS_ERR(desc))
1267 			continue;
1268 
1269 		ret = gpiod_hog(desc, name, lflags, dflags);
1270 		if (ret) {
1271 			dev_err(chip->parent, "Failed to hog GPIO\n");
1272 			fwnode_handle_put(fwnode);
1273 			return;
1274 		}
1275 	}
1276 }
1277 
1278 void acpi_gpiochip_add(struct gpio_chip *chip)
1279 {
1280 	struct acpi_gpio_chip *acpi_gpio;
1281 	struct acpi_device *adev;
1282 	acpi_status status;
1283 
1284 	if (!chip || !chip->parent)
1285 		return;
1286 
1287 	adev = ACPI_COMPANION(chip->parent);
1288 	if (!adev)
1289 		return;
1290 
1291 	acpi_gpio = kzalloc(sizeof(*acpi_gpio), GFP_KERNEL);
1292 	if (!acpi_gpio) {
1293 		dev_err(chip->parent,
1294 			"Failed to allocate memory for ACPI GPIO chip\n");
1295 		return;
1296 	}
1297 
1298 	acpi_gpio->chip = chip;
1299 	INIT_LIST_HEAD(&acpi_gpio->events);
1300 	INIT_LIST_HEAD(&acpi_gpio->deferred_req_irqs_list_entry);
1301 
1302 	status = acpi_attach_data(adev->handle, acpi_gpio_chip_dh, acpi_gpio);
1303 	if (ACPI_FAILURE(status)) {
1304 		dev_err(chip->parent, "Failed to attach ACPI GPIO chip\n");
1305 		kfree(acpi_gpio);
1306 		return;
1307 	}
1308 
1309 	acpi_gpiochip_request_regions(acpi_gpio);
1310 	acpi_gpiochip_scan_gpios(acpi_gpio);
1311 	acpi_dev_clear_dependencies(adev);
1312 }
1313 
1314 void acpi_gpiochip_remove(struct gpio_chip *chip)
1315 {
1316 	struct acpi_gpio_chip *acpi_gpio;
1317 	acpi_handle handle;
1318 	acpi_status status;
1319 
1320 	if (!chip || !chip->parent)
1321 		return;
1322 
1323 	handle = ACPI_HANDLE(chip->parent);
1324 	if (!handle)
1325 		return;
1326 
1327 	status = acpi_get_data(handle, acpi_gpio_chip_dh, (void **)&acpi_gpio);
1328 	if (ACPI_FAILURE(status)) {
1329 		dev_warn(chip->parent, "Failed to retrieve ACPI GPIO chip\n");
1330 		return;
1331 	}
1332 
1333 	acpi_gpiochip_free_regions(acpi_gpio);
1334 
1335 	acpi_detach_data(handle, acpi_gpio_chip_dh);
1336 	kfree(acpi_gpio);
1337 }
1338 
1339 void acpi_gpio_dev_init(struct gpio_chip *gc, struct gpio_device *gdev)
1340 {
1341 	/* Set default fwnode to parent's one if present */
1342 	if (gc->parent)
1343 		ACPI_COMPANION_SET(&gdev->dev, ACPI_COMPANION(gc->parent));
1344 
1345 	if (gc->fwnode)
1346 		device_set_node(&gdev->dev, gc->fwnode);
1347 }
1348 
1349 static int acpi_gpio_package_count(const union acpi_object *obj)
1350 {
1351 	const union acpi_object *element = obj->package.elements;
1352 	const union acpi_object *end = element + obj->package.count;
1353 	unsigned int count = 0;
1354 
1355 	while (element < end) {
1356 		switch (element->type) {
1357 		case ACPI_TYPE_LOCAL_REFERENCE:
1358 			element += 3;
1359 			fallthrough;
1360 		case ACPI_TYPE_INTEGER:
1361 			element++;
1362 			count++;
1363 			break;
1364 
1365 		default:
1366 			return -EPROTO;
1367 		}
1368 	}
1369 
1370 	return count;
1371 }
1372 
1373 static int acpi_find_gpio_count(struct acpi_resource *ares, void *data)
1374 {
1375 	unsigned int *count = data;
1376 
1377 	if (ares->type == ACPI_RESOURCE_TYPE_GPIO)
1378 		*count += ares->data.gpio.pin_table_length;
1379 
1380 	return 1;
1381 }
1382 
1383 /**
1384  * acpi_gpio_count - count the GPIOs associated with a device / function
1385  * @dev:	GPIO consumer, can be %NULL for system-global GPIOs
1386  * @con_id:	function within the GPIO consumer
1387  *
1388  * Return:
1389  * The number of GPIOs associated with a device / function or %-ENOENT,
1390  * if no GPIO has been assigned to the requested function.
1391  */
1392 int acpi_gpio_count(struct device *dev, const char *con_id)
1393 {
1394 	struct acpi_device *adev = ACPI_COMPANION(dev);
1395 	const union acpi_object *obj;
1396 	const struct acpi_gpio_mapping *gm;
1397 	int count = -ENOENT;
1398 	int ret;
1399 	char propname[32];
1400 	unsigned int i;
1401 
1402 	/* Try first from _DSD */
1403 	for (i = 0; i < ARRAY_SIZE(gpio_suffixes); i++) {
1404 		if (con_id)
1405 			snprintf(propname, sizeof(propname), "%s-%s",
1406 				 con_id, gpio_suffixes[i]);
1407 		else
1408 			snprintf(propname, sizeof(propname), "%s",
1409 				 gpio_suffixes[i]);
1410 
1411 		ret = acpi_dev_get_property(adev, propname, ACPI_TYPE_ANY,
1412 					    &obj);
1413 		if (ret == 0) {
1414 			if (obj->type == ACPI_TYPE_LOCAL_REFERENCE)
1415 				count = 1;
1416 			else if (obj->type == ACPI_TYPE_PACKAGE)
1417 				count = acpi_gpio_package_count(obj);
1418 		} else if (adev->driver_gpios) {
1419 			for (gm = adev->driver_gpios; gm->name; gm++)
1420 				if (strcmp(propname, gm->name) == 0) {
1421 					count = gm->size;
1422 					break;
1423 				}
1424 		}
1425 		if (count > 0)
1426 			break;
1427 	}
1428 
1429 	/* Then from plain _CRS GPIOs */
1430 	if (count < 0) {
1431 		struct list_head resource_list;
1432 		unsigned int crs_count = 0;
1433 
1434 		if (!acpi_can_fallback_to_crs(adev, con_id))
1435 			return count;
1436 
1437 		INIT_LIST_HEAD(&resource_list);
1438 		acpi_dev_get_resources(adev, &resource_list,
1439 				       acpi_find_gpio_count, &crs_count);
1440 		acpi_dev_free_resource_list(&resource_list);
1441 		if (crs_count > 0)
1442 			count = crs_count;
1443 	}
1444 	return count ? count : -ENOENT;
1445 }
1446 
1447 /* Run deferred acpi_gpiochip_request_irqs() */
1448 static int __init acpi_gpio_handle_deferred_request_irqs(void)
1449 {
1450 	struct acpi_gpio_chip *acpi_gpio, *tmp;
1451 
1452 	mutex_lock(&acpi_gpio_deferred_req_irqs_lock);
1453 	list_for_each_entry_safe(acpi_gpio, tmp,
1454 				 &acpi_gpio_deferred_req_irqs_list,
1455 				 deferred_req_irqs_list_entry)
1456 		acpi_gpiochip_request_irqs(acpi_gpio);
1457 
1458 	acpi_gpio_deferred_req_irqs_done = true;
1459 	mutex_unlock(&acpi_gpio_deferred_req_irqs_lock);
1460 
1461 	return 0;
1462 }
1463 /* We must use _sync so that this runs after the first deferred_probe run */
1464 late_initcall_sync(acpi_gpio_handle_deferred_request_irqs);
1465 
1466 static const struct dmi_system_id gpiolib_acpi_quirks[] __initconst = {
1467 	{
1468 		/*
1469 		 * The Minix Neo Z83-4 has a micro-USB-B id-pin handler for
1470 		 * a non existing micro-USB-B connector which puts the HDMI
1471 		 * DDC pins in GPIO mode, breaking HDMI support.
1472 		 */
1473 		.matches = {
1474 			DMI_MATCH(DMI_SYS_VENDOR, "MINIX"),
1475 			DMI_MATCH(DMI_PRODUCT_NAME, "Z83-4"),
1476 		},
1477 		.driver_data = &(struct acpi_gpiolib_dmi_quirk) {
1478 			.no_edge_events_on_boot = true,
1479 		},
1480 	},
1481 	{
1482 		/*
1483 		 * The Terra Pad 1061 has a micro-USB-B id-pin handler, which
1484 		 * instead of controlling the actual micro-USB-B turns the 5V
1485 		 * boost for its USB-A connector off. The actual micro-USB-B
1486 		 * connector is wired for charging only.
1487 		 */
1488 		.matches = {
1489 			DMI_MATCH(DMI_SYS_VENDOR, "Wortmann_AG"),
1490 			DMI_MATCH(DMI_PRODUCT_NAME, "TERRA_PAD_1061"),
1491 		},
1492 		.driver_data = &(struct acpi_gpiolib_dmi_quirk) {
1493 			.no_edge_events_on_boot = true,
1494 		},
1495 	},
1496 	{
1497 		/*
1498 		 * The Dell Venue 10 Pro 5055, with Bay Trail SoC + TI PMIC uses an
1499 		 * external embedded-controller connected via I2C + an ACPI GPIO
1500 		 * event handler on INT33FFC:02 pin 12, causing spurious wakeups.
1501 		 */
1502 		.matches = {
1503 			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
1504 			DMI_MATCH(DMI_PRODUCT_NAME, "Venue 10 Pro 5055"),
1505 		},
1506 		.driver_data = &(struct acpi_gpiolib_dmi_quirk) {
1507 			.ignore_wake = "INT33FC:02@12",
1508 		},
1509 	},
1510 	{
1511 		/*
1512 		 * HP X2 10 models with Cherry Trail SoC + TI PMIC use an
1513 		 * external embedded-controller connected via I2C + an ACPI GPIO
1514 		 * event handler on INT33FF:01 pin 0, causing spurious wakeups.
1515 		 * When suspending by closing the LID, the power to the USB
1516 		 * keyboard is turned off, causing INT0002 ACPI events to
1517 		 * trigger once the XHCI controller notices the keyboard is
1518 		 * gone. So INT0002 events cause spurious wakeups too. Ignoring
1519 		 * EC wakes breaks wakeup when opening the lid, the user needs
1520 		 * to press the power-button to wakeup the system. The
1521 		 * alternative is suspend simply not working, which is worse.
1522 		 */
1523 		.matches = {
1524 			DMI_MATCH(DMI_SYS_VENDOR, "HP"),
1525 			DMI_MATCH(DMI_PRODUCT_NAME, "HP x2 Detachable 10-p0XX"),
1526 		},
1527 		.driver_data = &(struct acpi_gpiolib_dmi_quirk) {
1528 			.ignore_wake = "INT33FF:01@0,INT0002:00@2",
1529 		},
1530 	},
1531 	{
1532 		/*
1533 		 * HP X2 10 models with Bay Trail SoC + AXP288 PMIC use an
1534 		 * external embedded-controller connected via I2C + an ACPI GPIO
1535 		 * event handler on INT33FC:02 pin 28, causing spurious wakeups.
1536 		 */
1537 		.matches = {
1538 			DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
1539 			DMI_MATCH(DMI_PRODUCT_NAME, "HP Pavilion x2 Detachable"),
1540 			DMI_MATCH(DMI_BOARD_NAME, "815D"),
1541 		},
1542 		.driver_data = &(struct acpi_gpiolib_dmi_quirk) {
1543 			.ignore_wake = "INT33FC:02@28",
1544 		},
1545 	},
1546 	{
1547 		/*
1548 		 * HP X2 10 models with Cherry Trail SoC + AXP288 PMIC use an
1549 		 * external embedded-controller connected via I2C + an ACPI GPIO
1550 		 * event handler on INT33FF:01 pin 0, causing spurious wakeups.
1551 		 */
1552 		.matches = {
1553 			DMI_MATCH(DMI_SYS_VENDOR, "HP"),
1554 			DMI_MATCH(DMI_PRODUCT_NAME, "HP Pavilion x2 Detachable"),
1555 			DMI_MATCH(DMI_BOARD_NAME, "813E"),
1556 		},
1557 		.driver_data = &(struct acpi_gpiolib_dmi_quirk) {
1558 			.ignore_wake = "INT33FF:01@0",
1559 		},
1560 	},
1561 	{} /* Terminating entry */
1562 };
1563 
1564 static int __init acpi_gpio_setup_params(void)
1565 {
1566 	const struct acpi_gpiolib_dmi_quirk *quirk = NULL;
1567 	const struct dmi_system_id *id;
1568 
1569 	id = dmi_first_match(gpiolib_acpi_quirks);
1570 	if (id)
1571 		quirk = id->driver_data;
1572 
1573 	if (run_edge_events_on_boot < 0) {
1574 		if (quirk && quirk->no_edge_events_on_boot)
1575 			run_edge_events_on_boot = 0;
1576 		else
1577 			run_edge_events_on_boot = 1;
1578 	}
1579 
1580 	if (ignore_wake == NULL && quirk && quirk->ignore_wake)
1581 		ignore_wake = quirk->ignore_wake;
1582 
1583 	return 0;
1584 }
1585 
1586 /* Directly after dmi_setup() which runs as core_initcall() */
1587 postcore_initcall(acpi_gpio_setup_params);
1588