xref: /openbmc/linux/drivers/gpio/gpiolib-acpi.c (revision 359745d7)
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 	ret = gpio_set_debounce_timeout(desc, agpio->debounce_timeout);
311 	if (ret)
312 		dev_warn(chip->parent,
313 			 "Failed to set debounce-timeout for pin 0x%04X, err %d\n",
314 			 pin, ret);
315 
316 	return desc;
317 }
318 
319 static bool acpi_gpio_in_ignore_list(const char *controller_in, int pin_in)
320 {
321 	const char *controller, *pin_str;
322 	int len, pin;
323 	char *endp;
324 
325 	controller = ignore_wake;
326 	while (controller) {
327 		pin_str = strchr(controller, '@');
328 		if (!pin_str)
329 			goto err;
330 
331 		len = pin_str - controller;
332 		if (len == strlen(controller_in) &&
333 		    strncmp(controller, controller_in, len) == 0) {
334 			pin = simple_strtoul(pin_str + 1, &endp, 10);
335 			if (*endp != 0 && *endp != ',')
336 				goto err;
337 
338 			if (pin == pin_in)
339 				return true;
340 		}
341 
342 		controller = strchr(controller, ',');
343 		if (controller)
344 			controller++;
345 	}
346 
347 	return false;
348 err:
349 	pr_err_once("Error: Invalid value for gpiolib_acpi.ignore_wake: %s\n", ignore_wake);
350 	return false;
351 }
352 
353 static bool acpi_gpio_irq_is_wake(struct device *parent,
354 				  struct acpi_resource_gpio *agpio)
355 {
356 	int pin = agpio->pin_table[0];
357 
358 	if (agpio->wake_capable != ACPI_WAKE_CAPABLE)
359 		return false;
360 
361 	if (acpi_gpio_in_ignore_list(dev_name(parent), pin)) {
362 		dev_info(parent, "Ignoring wakeup on pin %d\n", pin);
363 		return false;
364 	}
365 
366 	return true;
367 }
368 
369 /* Always returns AE_OK so that we keep looping over the resources */
370 static acpi_status acpi_gpiochip_alloc_event(struct acpi_resource *ares,
371 					     void *context)
372 {
373 	struct acpi_gpio_chip *acpi_gpio = context;
374 	struct gpio_chip *chip = acpi_gpio->chip;
375 	struct acpi_resource_gpio *agpio;
376 	acpi_handle handle, evt_handle;
377 	struct acpi_gpio_event *event;
378 	irq_handler_t handler = NULL;
379 	struct gpio_desc *desc;
380 	int ret, pin, irq;
381 
382 	if (!acpi_gpio_get_irq_resource(ares, &agpio))
383 		return AE_OK;
384 
385 	handle = ACPI_HANDLE(chip->parent);
386 	pin = agpio->pin_table[0];
387 
388 	if (pin <= 255) {
389 		char ev_name[5];
390 		sprintf(ev_name, "_%c%02hhX",
391 			agpio->triggering == ACPI_EDGE_SENSITIVE ? 'E' : 'L',
392 			pin);
393 		if (ACPI_SUCCESS(acpi_get_handle(handle, ev_name, &evt_handle)))
394 			handler = acpi_gpio_irq_handler;
395 	}
396 	if (!handler) {
397 		if (ACPI_SUCCESS(acpi_get_handle(handle, "_EVT", &evt_handle)))
398 			handler = acpi_gpio_irq_handler_evt;
399 	}
400 	if (!handler)
401 		return AE_OK;
402 
403 	desc = acpi_request_own_gpiod(chip, agpio, 0, "ACPI:Event");
404 	if (IS_ERR(desc)) {
405 		dev_err(chip->parent,
406 			"Failed to request GPIO for pin 0x%04X, err %ld\n",
407 			pin, PTR_ERR(desc));
408 		return AE_OK;
409 	}
410 
411 	ret = gpiochip_lock_as_irq(chip, pin);
412 	if (ret) {
413 		dev_err(chip->parent,
414 			"Failed to lock GPIO pin 0x%04X as interrupt, err %d\n",
415 			pin, ret);
416 		goto fail_free_desc;
417 	}
418 
419 	irq = gpiod_to_irq(desc);
420 	if (irq < 0) {
421 		dev_err(chip->parent,
422 			"Failed to translate GPIO pin 0x%04X to IRQ, err %d\n",
423 			pin, irq);
424 		goto fail_unlock_irq;
425 	}
426 
427 	event = kzalloc(sizeof(*event), GFP_KERNEL);
428 	if (!event)
429 		goto fail_unlock_irq;
430 
431 	event->irqflags = IRQF_ONESHOT;
432 	if (agpio->triggering == ACPI_LEVEL_SENSITIVE) {
433 		if (agpio->polarity == ACPI_ACTIVE_HIGH)
434 			event->irqflags |= IRQF_TRIGGER_HIGH;
435 		else
436 			event->irqflags |= IRQF_TRIGGER_LOW;
437 	} else {
438 		switch (agpio->polarity) {
439 		case ACPI_ACTIVE_HIGH:
440 			event->irqflags |= IRQF_TRIGGER_RISING;
441 			break;
442 		case ACPI_ACTIVE_LOW:
443 			event->irqflags |= IRQF_TRIGGER_FALLING;
444 			break;
445 		default:
446 			event->irqflags |= IRQF_TRIGGER_RISING |
447 					   IRQF_TRIGGER_FALLING;
448 			break;
449 		}
450 	}
451 
452 	event->handle = evt_handle;
453 	event->handler = handler;
454 	event->irq = irq;
455 	event->irq_is_wake = acpi_gpio_irq_is_wake(chip->parent, agpio);
456 	event->pin = pin;
457 	event->desc = desc;
458 
459 	list_add_tail(&event->node, &acpi_gpio->events);
460 
461 	return AE_OK;
462 
463 fail_unlock_irq:
464 	gpiochip_unlock_as_irq(chip, pin);
465 fail_free_desc:
466 	gpiochip_free_own_desc(desc);
467 
468 	return AE_OK;
469 }
470 
471 /**
472  * acpi_gpiochip_request_interrupts() - Register isr for gpio chip ACPI events
473  * @chip:      GPIO chip
474  *
475  * ACPI5 platforms can use GPIO signaled ACPI events. These GPIO interrupts are
476  * handled by ACPI event methods which need to be called from the GPIO
477  * chip's interrupt handler. acpi_gpiochip_request_interrupts() finds out which
478  * GPIO pins have ACPI event methods and assigns interrupt handlers that calls
479  * the ACPI event methods for those pins.
480  */
481 void acpi_gpiochip_request_interrupts(struct gpio_chip *chip)
482 {
483 	struct acpi_gpio_chip *acpi_gpio;
484 	acpi_handle handle;
485 	acpi_status status;
486 	bool defer;
487 
488 	if (!chip->parent || !chip->to_irq)
489 		return;
490 
491 	handle = ACPI_HANDLE(chip->parent);
492 	if (!handle)
493 		return;
494 
495 	status = acpi_get_data(handle, acpi_gpio_chip_dh, (void **)&acpi_gpio);
496 	if (ACPI_FAILURE(status))
497 		return;
498 
499 	acpi_walk_resources(handle, "_AEI",
500 			    acpi_gpiochip_alloc_event, acpi_gpio);
501 
502 	mutex_lock(&acpi_gpio_deferred_req_irqs_lock);
503 	defer = !acpi_gpio_deferred_req_irqs_done;
504 	if (defer)
505 		list_add(&acpi_gpio->deferred_req_irqs_list_entry,
506 			 &acpi_gpio_deferred_req_irqs_list);
507 	mutex_unlock(&acpi_gpio_deferred_req_irqs_lock);
508 
509 	if (defer)
510 		return;
511 
512 	acpi_gpiochip_request_irqs(acpi_gpio);
513 }
514 EXPORT_SYMBOL_GPL(acpi_gpiochip_request_interrupts);
515 
516 /**
517  * acpi_gpiochip_free_interrupts() - Free GPIO ACPI event interrupts.
518  * @chip:      GPIO chip
519  *
520  * Free interrupts associated with GPIO ACPI event method for the given
521  * GPIO chip.
522  */
523 void acpi_gpiochip_free_interrupts(struct gpio_chip *chip)
524 {
525 	struct acpi_gpio_chip *acpi_gpio;
526 	struct acpi_gpio_event *event, *ep;
527 	acpi_handle handle;
528 	acpi_status status;
529 
530 	if (!chip->parent || !chip->to_irq)
531 		return;
532 
533 	handle = ACPI_HANDLE(chip->parent);
534 	if (!handle)
535 		return;
536 
537 	status = acpi_get_data(handle, acpi_gpio_chip_dh, (void **)&acpi_gpio);
538 	if (ACPI_FAILURE(status))
539 		return;
540 
541 	mutex_lock(&acpi_gpio_deferred_req_irqs_lock);
542 	if (!list_empty(&acpi_gpio->deferred_req_irqs_list_entry))
543 		list_del_init(&acpi_gpio->deferred_req_irqs_list_entry);
544 	mutex_unlock(&acpi_gpio_deferred_req_irqs_lock);
545 
546 	list_for_each_entry_safe_reverse(event, ep, &acpi_gpio->events, node) {
547 		if (event->irq_requested) {
548 			if (event->irq_is_wake)
549 				disable_irq_wake(event->irq);
550 
551 			free_irq(event->irq, event);
552 		}
553 
554 		gpiochip_unlock_as_irq(chip, event->pin);
555 		gpiochip_free_own_desc(event->desc);
556 		list_del(&event->node);
557 		kfree(event);
558 	}
559 }
560 EXPORT_SYMBOL_GPL(acpi_gpiochip_free_interrupts);
561 
562 int acpi_dev_add_driver_gpios(struct acpi_device *adev,
563 			      const struct acpi_gpio_mapping *gpios)
564 {
565 	if (adev && gpios) {
566 		adev->driver_gpios = gpios;
567 		return 0;
568 	}
569 	return -EINVAL;
570 }
571 EXPORT_SYMBOL_GPL(acpi_dev_add_driver_gpios);
572 
573 void acpi_dev_remove_driver_gpios(struct acpi_device *adev)
574 {
575 	if (adev)
576 		adev->driver_gpios = NULL;
577 }
578 EXPORT_SYMBOL_GPL(acpi_dev_remove_driver_gpios);
579 
580 static void acpi_dev_release_driver_gpios(void *adev)
581 {
582 	acpi_dev_remove_driver_gpios(adev);
583 }
584 
585 int devm_acpi_dev_add_driver_gpios(struct device *dev,
586 				   const struct acpi_gpio_mapping *gpios)
587 {
588 	struct acpi_device *adev = ACPI_COMPANION(dev);
589 	int ret;
590 
591 	ret = acpi_dev_add_driver_gpios(adev, gpios);
592 	if (ret)
593 		return ret;
594 
595 	return devm_add_action_or_reset(dev, acpi_dev_release_driver_gpios, adev);
596 }
597 EXPORT_SYMBOL_GPL(devm_acpi_dev_add_driver_gpios);
598 
599 static bool acpi_get_driver_gpio_data(struct acpi_device *adev,
600 				      const char *name, int index,
601 				      struct fwnode_reference_args *args,
602 				      unsigned int *quirks)
603 {
604 	const struct acpi_gpio_mapping *gm;
605 
606 	if (!adev->driver_gpios)
607 		return false;
608 
609 	for (gm = adev->driver_gpios; gm->name; gm++)
610 		if (!strcmp(name, gm->name) && gm->data && index < gm->size) {
611 			const struct acpi_gpio_params *par = gm->data + index;
612 
613 			args->fwnode = acpi_fwnode_handle(adev);
614 			args->args[0] = par->crs_entry_index;
615 			args->args[1] = par->line_index;
616 			args->args[2] = par->active_low;
617 			args->nargs = 3;
618 
619 			*quirks = gm->quirks;
620 			return true;
621 		}
622 
623 	return false;
624 }
625 
626 static int
627 __acpi_gpio_update_gpiod_flags(enum gpiod_flags *flags, enum gpiod_flags update)
628 {
629 	const enum gpiod_flags mask =
630 		GPIOD_FLAGS_BIT_DIR_SET | GPIOD_FLAGS_BIT_DIR_OUT |
631 		GPIOD_FLAGS_BIT_DIR_VAL;
632 	int ret = 0;
633 
634 	/*
635 	 * Check if the BIOS has IoRestriction with explicitly set direction
636 	 * and update @flags accordingly. Otherwise use whatever caller asked
637 	 * for.
638 	 */
639 	if (update & GPIOD_FLAGS_BIT_DIR_SET) {
640 		enum gpiod_flags diff = *flags ^ update;
641 
642 		/*
643 		 * Check if caller supplied incompatible GPIO initialization
644 		 * flags.
645 		 *
646 		 * Return %-EINVAL to notify that firmware has different
647 		 * settings and we are going to use them.
648 		 */
649 		if (((*flags & GPIOD_FLAGS_BIT_DIR_SET) && (diff & GPIOD_FLAGS_BIT_DIR_OUT)) ||
650 		    ((*flags & GPIOD_FLAGS_BIT_DIR_OUT) && (diff & GPIOD_FLAGS_BIT_DIR_VAL)))
651 			ret = -EINVAL;
652 		*flags = (*flags & ~mask) | (update & mask);
653 	}
654 	return ret;
655 }
656 
657 int
658 acpi_gpio_update_gpiod_flags(enum gpiod_flags *flags, struct acpi_gpio_info *info)
659 {
660 	struct device *dev = &info->adev->dev;
661 	enum gpiod_flags old = *flags;
662 	int ret;
663 
664 	ret = __acpi_gpio_update_gpiod_flags(&old, info->flags);
665 	if (info->quirks & ACPI_GPIO_QUIRK_NO_IO_RESTRICTION) {
666 		if (ret)
667 			dev_warn(dev, FW_BUG "GPIO not in correct mode, fixing\n");
668 	} else {
669 		if (ret)
670 			dev_dbg(dev, "Override GPIO initialization flags\n");
671 		*flags = old;
672 	}
673 
674 	return ret;
675 }
676 
677 int acpi_gpio_update_gpiod_lookup_flags(unsigned long *lookupflags,
678 					struct acpi_gpio_info *info)
679 {
680 	switch (info->pin_config) {
681 	case ACPI_PIN_CONFIG_PULLUP:
682 		*lookupflags |= GPIO_PULL_UP;
683 		break;
684 	case ACPI_PIN_CONFIG_PULLDOWN:
685 		*lookupflags |= GPIO_PULL_DOWN;
686 		break;
687 	default:
688 		break;
689 	}
690 
691 	if (info->polarity == GPIO_ACTIVE_LOW)
692 		*lookupflags |= GPIO_ACTIVE_LOW;
693 
694 	return 0;
695 }
696 
697 struct acpi_gpio_lookup {
698 	struct acpi_gpio_info info;
699 	int index;
700 	u16 pin_index;
701 	bool active_low;
702 	struct gpio_desc *desc;
703 	int n;
704 };
705 
706 static int acpi_populate_gpio_lookup(struct acpi_resource *ares, void *data)
707 {
708 	struct acpi_gpio_lookup *lookup = data;
709 
710 	if (ares->type != ACPI_RESOURCE_TYPE_GPIO)
711 		return 1;
712 
713 	if (!lookup->desc) {
714 		const struct acpi_resource_gpio *agpio = &ares->data.gpio;
715 		bool gpioint = agpio->connection_type == ACPI_RESOURCE_GPIO_TYPE_INT;
716 		struct gpio_desc *desc;
717 		u16 pin_index;
718 
719 		if (lookup->info.quirks & ACPI_GPIO_QUIRK_ONLY_GPIOIO && gpioint)
720 			lookup->index++;
721 
722 		if (lookup->n++ != lookup->index)
723 			return 1;
724 
725 		pin_index = lookup->pin_index;
726 		if (pin_index >= agpio->pin_table_length)
727 			return 1;
728 
729 		if (lookup->info.quirks & ACPI_GPIO_QUIRK_ABSOLUTE_NUMBER)
730 			desc = gpio_to_desc(agpio->pin_table[pin_index]);
731 		else
732 			desc = acpi_get_gpiod(agpio->resource_source.string_ptr,
733 					      agpio->pin_table[pin_index]);
734 		lookup->desc = desc;
735 		lookup->info.pin_config = agpio->pin_config;
736 		lookup->info.debounce = agpio->debounce_timeout;
737 		lookup->info.gpioint = gpioint;
738 
739 		/*
740 		 * Polarity and triggering are only specified for GpioInt
741 		 * resource.
742 		 * Note: we expect here:
743 		 * - ACPI_ACTIVE_LOW == GPIO_ACTIVE_LOW
744 		 * - ACPI_ACTIVE_HIGH == GPIO_ACTIVE_HIGH
745 		 */
746 		if (lookup->info.gpioint) {
747 			lookup->info.polarity = agpio->polarity;
748 			lookup->info.triggering = agpio->triggering;
749 		} else {
750 			lookup->info.polarity = lookup->active_low;
751 		}
752 
753 		lookup->info.flags = acpi_gpio_to_gpiod_flags(agpio, lookup->info.polarity);
754 	}
755 
756 	return 1;
757 }
758 
759 static int acpi_gpio_resource_lookup(struct acpi_gpio_lookup *lookup,
760 				     struct acpi_gpio_info *info)
761 {
762 	struct acpi_device *adev = lookup->info.adev;
763 	struct list_head res_list;
764 	int ret;
765 
766 	INIT_LIST_HEAD(&res_list);
767 
768 	ret = acpi_dev_get_resources(adev, &res_list,
769 				     acpi_populate_gpio_lookup,
770 				     lookup);
771 	if (ret < 0)
772 		return ret;
773 
774 	acpi_dev_free_resource_list(&res_list);
775 
776 	if (!lookup->desc)
777 		return -ENOENT;
778 
779 	if (info)
780 		*info = lookup->info;
781 	return 0;
782 }
783 
784 static int acpi_gpio_property_lookup(struct fwnode_handle *fwnode,
785 				     const char *propname, int index,
786 				     struct acpi_gpio_lookup *lookup)
787 {
788 	struct fwnode_reference_args args;
789 	unsigned int quirks = 0;
790 	int ret;
791 
792 	memset(&args, 0, sizeof(args));
793 	ret = __acpi_node_get_property_reference(fwnode, propname, index, 3,
794 						 &args);
795 	if (ret) {
796 		struct acpi_device *adev = to_acpi_device_node(fwnode);
797 
798 		if (!adev)
799 			return ret;
800 
801 		if (!acpi_get_driver_gpio_data(adev, propname, index, &args,
802 					       &quirks))
803 			return ret;
804 	}
805 	/*
806 	 * The property was found and resolved, so need to lookup the GPIO based
807 	 * on returned args.
808 	 */
809 	if (!to_acpi_device_node(args.fwnode))
810 		return -EINVAL;
811 	if (args.nargs != 3)
812 		return -EPROTO;
813 
814 	lookup->index = args.args[0];
815 	lookup->pin_index = args.args[1];
816 	lookup->active_low = !!args.args[2];
817 
818 	lookup->info.adev = to_acpi_device_node(args.fwnode);
819 	lookup->info.quirks = quirks;
820 
821 	return 0;
822 }
823 
824 /**
825  * acpi_get_gpiod_by_index() - get a GPIO descriptor from device resources
826  * @adev: pointer to a ACPI device to get GPIO from
827  * @propname: Property name of the GPIO (optional)
828  * @index: index of GpioIo/GpioInt resource (starting from %0)
829  * @info: info pointer to fill in (optional)
830  *
831  * Function goes through ACPI resources for @adev and based on @index looks
832  * up a GpioIo/GpioInt resource, translates it to the Linux GPIO descriptor,
833  * and returns it. @index matches GpioIo/GpioInt resources only so if there
834  * are total %3 GPIO resources, the index goes from %0 to %2.
835  *
836  * If @propname is specified the GPIO is looked using device property. In
837  * that case @index is used to select the GPIO entry in the property value
838  * (in case of multiple).
839  *
840  * If the GPIO cannot be translated or there is an error, an ERR_PTR is
841  * returned.
842  *
843  * Note: if the GPIO resource has multiple entries in the pin list, this
844  * function only returns the first.
845  */
846 static struct gpio_desc *acpi_get_gpiod_by_index(struct acpi_device *adev,
847 					  const char *propname, int index,
848 					  struct acpi_gpio_info *info)
849 {
850 	struct acpi_gpio_lookup lookup;
851 	int ret;
852 
853 	if (!adev)
854 		return ERR_PTR(-ENODEV);
855 
856 	memset(&lookup, 0, sizeof(lookup));
857 	lookup.index = index;
858 
859 	if (propname) {
860 		dev_dbg(&adev->dev, "GPIO: looking up %s\n", propname);
861 
862 		ret = acpi_gpio_property_lookup(acpi_fwnode_handle(adev),
863 						propname, index, &lookup);
864 		if (ret)
865 			return ERR_PTR(ret);
866 
867 		dev_dbg(&adev->dev, "GPIO: _DSD returned %s %d %u %u\n",
868 			dev_name(&lookup.info.adev->dev), lookup.index,
869 			lookup.pin_index, lookup.active_low);
870 	} else {
871 		dev_dbg(&adev->dev, "GPIO: looking up %d in _CRS\n", index);
872 		lookup.info.adev = adev;
873 	}
874 
875 	ret = acpi_gpio_resource_lookup(&lookup, info);
876 	return ret ? ERR_PTR(ret) : lookup.desc;
877 }
878 
879 static bool acpi_can_fallback_to_crs(struct acpi_device *adev,
880 				     const char *con_id)
881 {
882 	/* Never allow fallback if the device has properties */
883 	if (acpi_dev_has_props(adev) || adev->driver_gpios)
884 		return false;
885 
886 	return con_id == NULL;
887 }
888 
889 struct gpio_desc *acpi_find_gpio(struct device *dev,
890 				 const char *con_id,
891 				 unsigned int idx,
892 				 enum gpiod_flags *dflags,
893 				 unsigned long *lookupflags)
894 {
895 	struct acpi_device *adev = ACPI_COMPANION(dev);
896 	struct acpi_gpio_info info;
897 	struct gpio_desc *desc;
898 	char propname[32];
899 	int i;
900 
901 	/* Try first from _DSD */
902 	for (i = 0; i < ARRAY_SIZE(gpio_suffixes); i++) {
903 		if (con_id) {
904 			snprintf(propname, sizeof(propname), "%s-%s",
905 				 con_id, gpio_suffixes[i]);
906 		} else {
907 			snprintf(propname, sizeof(propname), "%s",
908 				 gpio_suffixes[i]);
909 		}
910 
911 		desc = acpi_get_gpiod_by_index(adev, propname, idx, &info);
912 		if (!IS_ERR(desc))
913 			break;
914 		if (PTR_ERR(desc) == -EPROBE_DEFER)
915 			return ERR_CAST(desc);
916 	}
917 
918 	/* Then from plain _CRS GPIOs */
919 	if (IS_ERR(desc)) {
920 		if (!acpi_can_fallback_to_crs(adev, con_id))
921 			return ERR_PTR(-ENOENT);
922 
923 		desc = acpi_get_gpiod_by_index(adev, NULL, idx, &info);
924 		if (IS_ERR(desc))
925 			return desc;
926 	}
927 
928 	if (info.gpioint &&
929 	    (*dflags == GPIOD_OUT_LOW || *dflags == GPIOD_OUT_HIGH)) {
930 		dev_dbg(&adev->dev, "refusing GpioInt() entry when doing GPIOD_OUT_* lookup\n");
931 		return ERR_PTR(-ENOENT);
932 	}
933 
934 	acpi_gpio_update_gpiod_flags(dflags, &info);
935 	acpi_gpio_update_gpiod_lookup_flags(lookupflags, &info);
936 	return desc;
937 }
938 
939 /**
940  * acpi_node_get_gpiod() - get a GPIO descriptor from ACPI resources
941  * @fwnode: pointer to an ACPI firmware node to get the GPIO information from
942  * @propname: Property name of the GPIO
943  * @index: index of GpioIo/GpioInt resource (starting from %0)
944  * @info: info pointer to fill in (optional)
945  *
946  * If @fwnode is an ACPI device object, call acpi_get_gpiod_by_index() for it.
947  * Otherwise (i.e. it is a data-only non-device object), use the property-based
948  * GPIO lookup to get to the GPIO resource with the relevant information and use
949  * that to obtain the GPIO descriptor to return.
950  *
951  * If the GPIO cannot be translated or there is an error an ERR_PTR is
952  * returned.
953  */
954 struct gpio_desc *acpi_node_get_gpiod(struct fwnode_handle *fwnode,
955 				      const char *propname, int index,
956 				      struct acpi_gpio_info *info)
957 {
958 	struct acpi_gpio_lookup lookup;
959 	struct acpi_device *adev;
960 	int ret;
961 
962 	adev = to_acpi_device_node(fwnode);
963 	if (adev)
964 		return acpi_get_gpiod_by_index(adev, propname, index, info);
965 
966 	if (!is_acpi_data_node(fwnode))
967 		return ERR_PTR(-ENODEV);
968 
969 	if (!propname)
970 		return ERR_PTR(-EINVAL);
971 
972 	memset(&lookup, 0, sizeof(lookup));
973 	lookup.index = index;
974 
975 	ret = acpi_gpio_property_lookup(fwnode, propname, index, &lookup);
976 	if (ret)
977 		return ERR_PTR(ret);
978 
979 	ret = acpi_gpio_resource_lookup(&lookup, info);
980 	return ret ? ERR_PTR(ret) : lookup.desc;
981 }
982 
983 /**
984  * acpi_dev_gpio_irq_get_by() - Find GpioInt and translate it to Linux IRQ number
985  * @adev: pointer to a ACPI device to get IRQ from
986  * @name: optional name of GpioInt resource
987  * @index: index of GpioInt resource (starting from %0)
988  *
989  * If the device has one or more GpioInt resources, this function can be
990  * used to translate from the GPIO offset in the resource to the Linux IRQ
991  * number.
992  *
993  * The function is idempotent, though each time it runs it will configure GPIO
994  * pin direction according to the flags in GpioInt resource.
995  *
996  * The function takes optional @name parameter. If the resource has a property
997  * name, then only those will be taken into account.
998  *
999  * Return: Linux IRQ number (> %0) on success, negative errno on failure.
1000  */
1001 int acpi_dev_gpio_irq_get_by(struct acpi_device *adev, const char *name, int index)
1002 {
1003 	int idx, i;
1004 	unsigned int irq_flags;
1005 	int ret;
1006 
1007 	for (i = 0, idx = 0; idx <= index; i++) {
1008 		struct acpi_gpio_info info;
1009 		struct gpio_desc *desc;
1010 
1011 		desc = acpi_get_gpiod_by_index(adev, name, i, &info);
1012 
1013 		/* Ignore -EPROBE_DEFER, it only matters if idx matches */
1014 		if (IS_ERR(desc) && PTR_ERR(desc) != -EPROBE_DEFER)
1015 			return PTR_ERR(desc);
1016 
1017 		if (info.gpioint && idx++ == index) {
1018 			unsigned long lflags = GPIO_LOOKUP_FLAGS_DEFAULT;
1019 			enum gpiod_flags dflags = GPIOD_ASIS;
1020 			char label[32];
1021 			int irq;
1022 
1023 			if (IS_ERR(desc))
1024 				return PTR_ERR(desc);
1025 
1026 			irq = gpiod_to_irq(desc);
1027 			if (irq < 0)
1028 				return irq;
1029 
1030 			acpi_gpio_update_gpiod_flags(&dflags, &info);
1031 			acpi_gpio_update_gpiod_lookup_flags(&lflags, &info);
1032 
1033 			snprintf(label, sizeof(label), "GpioInt() %d", index);
1034 			ret = gpiod_configure_flags(desc, label, lflags, dflags);
1035 			if (ret < 0)
1036 				return ret;
1037 
1038 			ret = gpio_set_debounce_timeout(desc, info.debounce);
1039 			if (ret)
1040 				return ret;
1041 
1042 			irq_flags = acpi_dev_get_irq_type(info.triggering,
1043 							  info.polarity);
1044 
1045 			/*
1046 			 * If the IRQ is not already in use then set type
1047 			 * if specified and different than the current one.
1048 			 */
1049 			if (can_request_irq(irq, irq_flags)) {
1050 				if (irq_flags != IRQ_TYPE_NONE &&
1051 				    irq_flags != irq_get_trigger_type(irq))
1052 					irq_set_irq_type(irq, irq_flags);
1053 			} else {
1054 				dev_dbg(&adev->dev, "IRQ %d already in use\n", irq);
1055 			}
1056 
1057 			return irq;
1058 		}
1059 
1060 	}
1061 	return -ENOENT;
1062 }
1063 EXPORT_SYMBOL_GPL(acpi_dev_gpio_irq_get_by);
1064 
1065 static acpi_status
1066 acpi_gpio_adr_space_handler(u32 function, acpi_physical_address address,
1067 			    u32 bits, u64 *value, void *handler_context,
1068 			    void *region_context)
1069 {
1070 	struct acpi_gpio_chip *achip = region_context;
1071 	struct gpio_chip *chip = achip->chip;
1072 	struct acpi_resource_gpio *agpio;
1073 	struct acpi_resource *ares;
1074 	u16 pin_index = address;
1075 	acpi_status status;
1076 	int length;
1077 	int i;
1078 
1079 	status = acpi_buffer_to_resource(achip->conn_info.connection,
1080 					 achip->conn_info.length, &ares);
1081 	if (ACPI_FAILURE(status))
1082 		return status;
1083 
1084 	if (WARN_ON(ares->type != ACPI_RESOURCE_TYPE_GPIO)) {
1085 		ACPI_FREE(ares);
1086 		return AE_BAD_PARAMETER;
1087 	}
1088 
1089 	agpio = &ares->data.gpio;
1090 
1091 	if (WARN_ON(agpio->io_restriction == ACPI_IO_RESTRICT_INPUT &&
1092 	    function == ACPI_WRITE)) {
1093 		ACPI_FREE(ares);
1094 		return AE_BAD_PARAMETER;
1095 	}
1096 
1097 	length = min_t(u16, agpio->pin_table_length, pin_index + bits);
1098 	for (i = pin_index; i < length; ++i) {
1099 		int pin = agpio->pin_table[i];
1100 		struct acpi_gpio_connection *conn;
1101 		struct gpio_desc *desc;
1102 		bool found;
1103 
1104 		mutex_lock(&achip->conn_lock);
1105 
1106 		found = false;
1107 		list_for_each_entry(conn, &achip->conns, node) {
1108 			if (conn->pin == pin) {
1109 				found = true;
1110 				desc = conn->desc;
1111 				break;
1112 			}
1113 		}
1114 
1115 		/*
1116 		 * The same GPIO can be shared between operation region and
1117 		 * event but only if the access here is ACPI_READ. In that
1118 		 * case we "borrow" the event GPIO instead.
1119 		 */
1120 		if (!found && agpio->shareable == ACPI_SHARED &&
1121 		     function == ACPI_READ) {
1122 			struct acpi_gpio_event *event;
1123 
1124 			list_for_each_entry(event, &achip->events, node) {
1125 				if (event->pin == pin) {
1126 					desc = event->desc;
1127 					found = true;
1128 					break;
1129 				}
1130 			}
1131 		}
1132 
1133 		if (!found) {
1134 			desc = acpi_request_own_gpiod(chip, agpio, i, "ACPI:OpRegion");
1135 			if (IS_ERR(desc)) {
1136 				mutex_unlock(&achip->conn_lock);
1137 				status = AE_ERROR;
1138 				goto out;
1139 			}
1140 
1141 			conn = kzalloc(sizeof(*conn), GFP_KERNEL);
1142 			if (!conn) {
1143 				gpiochip_free_own_desc(desc);
1144 				mutex_unlock(&achip->conn_lock);
1145 				status = AE_NO_MEMORY;
1146 				goto out;
1147 			}
1148 
1149 			conn->pin = pin;
1150 			conn->desc = desc;
1151 			list_add_tail(&conn->node, &achip->conns);
1152 		}
1153 
1154 		mutex_unlock(&achip->conn_lock);
1155 
1156 		if (function == ACPI_WRITE)
1157 			gpiod_set_raw_value_cansleep(desc, !!(*value & BIT(i)));
1158 		else
1159 			*value |= (u64)gpiod_get_raw_value_cansleep(desc) << i;
1160 	}
1161 
1162 out:
1163 	ACPI_FREE(ares);
1164 	return status;
1165 }
1166 
1167 static void acpi_gpiochip_request_regions(struct acpi_gpio_chip *achip)
1168 {
1169 	struct gpio_chip *chip = achip->chip;
1170 	acpi_handle handle = ACPI_HANDLE(chip->parent);
1171 	acpi_status status;
1172 
1173 	INIT_LIST_HEAD(&achip->conns);
1174 	mutex_init(&achip->conn_lock);
1175 	status = acpi_install_address_space_handler(handle, ACPI_ADR_SPACE_GPIO,
1176 						    acpi_gpio_adr_space_handler,
1177 						    NULL, achip);
1178 	if (ACPI_FAILURE(status))
1179 		dev_err(chip->parent,
1180 		        "Failed to install GPIO OpRegion handler\n");
1181 }
1182 
1183 static void acpi_gpiochip_free_regions(struct acpi_gpio_chip *achip)
1184 {
1185 	struct gpio_chip *chip = achip->chip;
1186 	acpi_handle handle = ACPI_HANDLE(chip->parent);
1187 	struct acpi_gpio_connection *conn, *tmp;
1188 	acpi_status status;
1189 
1190 	status = acpi_remove_address_space_handler(handle, ACPI_ADR_SPACE_GPIO,
1191 						   acpi_gpio_adr_space_handler);
1192 	if (ACPI_FAILURE(status)) {
1193 		dev_err(chip->parent,
1194 			"Failed to remove GPIO OpRegion handler\n");
1195 		return;
1196 	}
1197 
1198 	list_for_each_entry_safe_reverse(conn, tmp, &achip->conns, node) {
1199 		gpiochip_free_own_desc(conn->desc);
1200 		list_del(&conn->node);
1201 		kfree(conn);
1202 	}
1203 }
1204 
1205 static struct gpio_desc *
1206 acpi_gpiochip_parse_own_gpio(struct acpi_gpio_chip *achip,
1207 			     struct fwnode_handle *fwnode,
1208 			     const char **name,
1209 			     unsigned long *lflags,
1210 			     enum gpiod_flags *dflags)
1211 {
1212 	struct gpio_chip *chip = achip->chip;
1213 	struct gpio_desc *desc;
1214 	u32 gpios[2];
1215 	int ret;
1216 
1217 	*lflags = GPIO_LOOKUP_FLAGS_DEFAULT;
1218 	*dflags = GPIOD_ASIS;
1219 	*name = NULL;
1220 
1221 	ret = fwnode_property_read_u32_array(fwnode, "gpios", gpios,
1222 					     ARRAY_SIZE(gpios));
1223 	if (ret < 0)
1224 		return ERR_PTR(ret);
1225 
1226 	desc = gpiochip_get_desc(chip, gpios[0]);
1227 	if (IS_ERR(desc))
1228 		return desc;
1229 
1230 	if (gpios[1])
1231 		*lflags |= GPIO_ACTIVE_LOW;
1232 
1233 	if (fwnode_property_present(fwnode, "input"))
1234 		*dflags |= GPIOD_IN;
1235 	else if (fwnode_property_present(fwnode, "output-low"))
1236 		*dflags |= GPIOD_OUT_LOW;
1237 	else if (fwnode_property_present(fwnode, "output-high"))
1238 		*dflags |= GPIOD_OUT_HIGH;
1239 	else
1240 		return ERR_PTR(-EINVAL);
1241 
1242 	fwnode_property_read_string(fwnode, "line-name", name);
1243 
1244 	return desc;
1245 }
1246 
1247 static void acpi_gpiochip_scan_gpios(struct acpi_gpio_chip *achip)
1248 {
1249 	struct gpio_chip *chip = achip->chip;
1250 	struct fwnode_handle *fwnode;
1251 
1252 	device_for_each_child_node(chip->parent, fwnode) {
1253 		unsigned long lflags;
1254 		enum gpiod_flags dflags;
1255 		struct gpio_desc *desc;
1256 		const char *name;
1257 		int ret;
1258 
1259 		if (!fwnode_property_present(fwnode, "gpio-hog"))
1260 			continue;
1261 
1262 		desc = acpi_gpiochip_parse_own_gpio(achip, fwnode, &name,
1263 						    &lflags, &dflags);
1264 		if (IS_ERR(desc))
1265 			continue;
1266 
1267 		ret = gpiod_hog(desc, name, lflags, dflags);
1268 		if (ret) {
1269 			dev_err(chip->parent, "Failed to hog GPIO\n");
1270 			fwnode_handle_put(fwnode);
1271 			return;
1272 		}
1273 	}
1274 }
1275 
1276 void acpi_gpiochip_add(struct gpio_chip *chip)
1277 {
1278 	struct acpi_gpio_chip *acpi_gpio;
1279 	struct acpi_device *adev;
1280 	acpi_status status;
1281 
1282 	if (!chip || !chip->parent)
1283 		return;
1284 
1285 	adev = ACPI_COMPANION(chip->parent);
1286 	if (!adev)
1287 		return;
1288 
1289 	acpi_gpio = kzalloc(sizeof(*acpi_gpio), GFP_KERNEL);
1290 	if (!acpi_gpio) {
1291 		dev_err(chip->parent,
1292 			"Failed to allocate memory for ACPI GPIO chip\n");
1293 		return;
1294 	}
1295 
1296 	acpi_gpio->chip = chip;
1297 	INIT_LIST_HEAD(&acpi_gpio->events);
1298 	INIT_LIST_HEAD(&acpi_gpio->deferred_req_irqs_list_entry);
1299 
1300 	status = acpi_attach_data(adev->handle, acpi_gpio_chip_dh, acpi_gpio);
1301 	if (ACPI_FAILURE(status)) {
1302 		dev_err(chip->parent, "Failed to attach ACPI GPIO chip\n");
1303 		kfree(acpi_gpio);
1304 		return;
1305 	}
1306 
1307 	acpi_gpiochip_request_regions(acpi_gpio);
1308 	acpi_gpiochip_scan_gpios(acpi_gpio);
1309 	acpi_dev_clear_dependencies(adev);
1310 }
1311 
1312 void acpi_gpiochip_remove(struct gpio_chip *chip)
1313 {
1314 	struct acpi_gpio_chip *acpi_gpio;
1315 	acpi_handle handle;
1316 	acpi_status status;
1317 
1318 	if (!chip || !chip->parent)
1319 		return;
1320 
1321 	handle = ACPI_HANDLE(chip->parent);
1322 	if (!handle)
1323 		return;
1324 
1325 	status = acpi_get_data(handle, acpi_gpio_chip_dh, (void **)&acpi_gpio);
1326 	if (ACPI_FAILURE(status)) {
1327 		dev_warn(chip->parent, "Failed to retrieve ACPI GPIO chip\n");
1328 		return;
1329 	}
1330 
1331 	acpi_gpiochip_free_regions(acpi_gpio);
1332 
1333 	acpi_detach_data(handle, acpi_gpio_chip_dh);
1334 	kfree(acpi_gpio);
1335 }
1336 
1337 void acpi_gpio_dev_init(struct gpio_chip *gc, struct gpio_device *gdev)
1338 {
1339 	/* Set default fwnode to parent's one if present */
1340 	if (gc->parent)
1341 		ACPI_COMPANION_SET(&gdev->dev, ACPI_COMPANION(gc->parent));
1342 
1343 	if (gc->fwnode)
1344 		device_set_node(&gdev->dev, gc->fwnode);
1345 }
1346 
1347 static int acpi_gpio_package_count(const union acpi_object *obj)
1348 {
1349 	const union acpi_object *element = obj->package.elements;
1350 	const union acpi_object *end = element + obj->package.count;
1351 	unsigned int count = 0;
1352 
1353 	while (element < end) {
1354 		switch (element->type) {
1355 		case ACPI_TYPE_LOCAL_REFERENCE:
1356 			element += 3;
1357 			fallthrough;
1358 		case ACPI_TYPE_INTEGER:
1359 			element++;
1360 			count++;
1361 			break;
1362 
1363 		default:
1364 			return -EPROTO;
1365 		}
1366 	}
1367 
1368 	return count;
1369 }
1370 
1371 static int acpi_find_gpio_count(struct acpi_resource *ares, void *data)
1372 {
1373 	unsigned int *count = data;
1374 
1375 	if (ares->type == ACPI_RESOURCE_TYPE_GPIO)
1376 		*count += ares->data.gpio.pin_table_length;
1377 
1378 	return 1;
1379 }
1380 
1381 /**
1382  * acpi_gpio_count - count the GPIOs associated with a device / function
1383  * @dev:	GPIO consumer, can be %NULL for system-global GPIOs
1384  * @con_id:	function within the GPIO consumer
1385  *
1386  * Return:
1387  * The number of GPIOs associated with a device / function or %-ENOENT,
1388  * if no GPIO has been assigned to the requested function.
1389  */
1390 int acpi_gpio_count(struct device *dev, const char *con_id)
1391 {
1392 	struct acpi_device *adev = ACPI_COMPANION(dev);
1393 	const union acpi_object *obj;
1394 	const struct acpi_gpio_mapping *gm;
1395 	int count = -ENOENT;
1396 	int ret;
1397 	char propname[32];
1398 	unsigned int i;
1399 
1400 	/* Try first from _DSD */
1401 	for (i = 0; i < ARRAY_SIZE(gpio_suffixes); i++) {
1402 		if (con_id)
1403 			snprintf(propname, sizeof(propname), "%s-%s",
1404 				 con_id, gpio_suffixes[i]);
1405 		else
1406 			snprintf(propname, sizeof(propname), "%s",
1407 				 gpio_suffixes[i]);
1408 
1409 		ret = acpi_dev_get_property(adev, propname, ACPI_TYPE_ANY,
1410 					    &obj);
1411 		if (ret == 0) {
1412 			if (obj->type == ACPI_TYPE_LOCAL_REFERENCE)
1413 				count = 1;
1414 			else if (obj->type == ACPI_TYPE_PACKAGE)
1415 				count = acpi_gpio_package_count(obj);
1416 		} else if (adev->driver_gpios) {
1417 			for (gm = adev->driver_gpios; gm->name; gm++)
1418 				if (strcmp(propname, gm->name) == 0) {
1419 					count = gm->size;
1420 					break;
1421 				}
1422 		}
1423 		if (count > 0)
1424 			break;
1425 	}
1426 
1427 	/* Then from plain _CRS GPIOs */
1428 	if (count < 0) {
1429 		struct list_head resource_list;
1430 		unsigned int crs_count = 0;
1431 
1432 		if (!acpi_can_fallback_to_crs(adev, con_id))
1433 			return count;
1434 
1435 		INIT_LIST_HEAD(&resource_list);
1436 		acpi_dev_get_resources(adev, &resource_list,
1437 				       acpi_find_gpio_count, &crs_count);
1438 		acpi_dev_free_resource_list(&resource_list);
1439 		if (crs_count > 0)
1440 			count = crs_count;
1441 	}
1442 	return count ? count : -ENOENT;
1443 }
1444 
1445 /* Run deferred acpi_gpiochip_request_irqs() */
1446 static int __init acpi_gpio_handle_deferred_request_irqs(void)
1447 {
1448 	struct acpi_gpio_chip *acpi_gpio, *tmp;
1449 
1450 	mutex_lock(&acpi_gpio_deferred_req_irqs_lock);
1451 	list_for_each_entry_safe(acpi_gpio, tmp,
1452 				 &acpi_gpio_deferred_req_irqs_list,
1453 				 deferred_req_irqs_list_entry)
1454 		acpi_gpiochip_request_irqs(acpi_gpio);
1455 
1456 	acpi_gpio_deferred_req_irqs_done = true;
1457 	mutex_unlock(&acpi_gpio_deferred_req_irqs_lock);
1458 
1459 	return 0;
1460 }
1461 /* We must use _sync so that this runs after the first deferred_probe run */
1462 late_initcall_sync(acpi_gpio_handle_deferred_request_irqs);
1463 
1464 static const struct dmi_system_id gpiolib_acpi_quirks[] __initconst = {
1465 	{
1466 		/*
1467 		 * The Minix Neo Z83-4 has a micro-USB-B id-pin handler for
1468 		 * a non existing micro-USB-B connector which puts the HDMI
1469 		 * DDC pins in GPIO mode, breaking HDMI support.
1470 		 */
1471 		.matches = {
1472 			DMI_MATCH(DMI_SYS_VENDOR, "MINIX"),
1473 			DMI_MATCH(DMI_PRODUCT_NAME, "Z83-4"),
1474 		},
1475 		.driver_data = &(struct acpi_gpiolib_dmi_quirk) {
1476 			.no_edge_events_on_boot = true,
1477 		},
1478 	},
1479 	{
1480 		/*
1481 		 * The Terra Pad 1061 has a micro-USB-B id-pin handler, which
1482 		 * instead of controlling the actual micro-USB-B turns the 5V
1483 		 * boost for its USB-A connector off. The actual micro-USB-B
1484 		 * connector is wired for charging only.
1485 		 */
1486 		.matches = {
1487 			DMI_MATCH(DMI_SYS_VENDOR, "Wortmann_AG"),
1488 			DMI_MATCH(DMI_PRODUCT_NAME, "TERRA_PAD_1061"),
1489 		},
1490 		.driver_data = &(struct acpi_gpiolib_dmi_quirk) {
1491 			.no_edge_events_on_boot = true,
1492 		},
1493 	},
1494 	{
1495 		/*
1496 		 * The Dell Venue 10 Pro 5055, with Bay Trail SoC + TI PMIC uses an
1497 		 * external embedded-controller connected via I2C + an ACPI GPIO
1498 		 * event handler on INT33FFC:02 pin 12, causing spurious wakeups.
1499 		 */
1500 		.matches = {
1501 			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
1502 			DMI_MATCH(DMI_PRODUCT_NAME, "Venue 10 Pro 5055"),
1503 		},
1504 		.driver_data = &(struct acpi_gpiolib_dmi_quirk) {
1505 			.ignore_wake = "INT33FC:02@12",
1506 		},
1507 	},
1508 	{
1509 		/*
1510 		 * HP X2 10 models with Cherry Trail SoC + TI PMIC use an
1511 		 * external embedded-controller connected via I2C + an ACPI GPIO
1512 		 * event handler on INT33FF:01 pin 0, causing spurious wakeups.
1513 		 * When suspending by closing the LID, the power to the USB
1514 		 * keyboard is turned off, causing INT0002 ACPI events to
1515 		 * trigger once the XHCI controller notices the keyboard is
1516 		 * gone. So INT0002 events cause spurious wakeups too. Ignoring
1517 		 * EC wakes breaks wakeup when opening the lid, the user needs
1518 		 * to press the power-button to wakeup the system. The
1519 		 * alternative is suspend simply not working, which is worse.
1520 		 */
1521 		.matches = {
1522 			DMI_MATCH(DMI_SYS_VENDOR, "HP"),
1523 			DMI_MATCH(DMI_PRODUCT_NAME, "HP x2 Detachable 10-p0XX"),
1524 		},
1525 		.driver_data = &(struct acpi_gpiolib_dmi_quirk) {
1526 			.ignore_wake = "INT33FF:01@0,INT0002:00@2",
1527 		},
1528 	},
1529 	{
1530 		/*
1531 		 * HP X2 10 models with Bay Trail SoC + AXP288 PMIC use an
1532 		 * external embedded-controller connected via I2C + an ACPI GPIO
1533 		 * event handler on INT33FC:02 pin 28, causing spurious wakeups.
1534 		 */
1535 		.matches = {
1536 			DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
1537 			DMI_MATCH(DMI_PRODUCT_NAME, "HP Pavilion x2 Detachable"),
1538 			DMI_MATCH(DMI_BOARD_NAME, "815D"),
1539 		},
1540 		.driver_data = &(struct acpi_gpiolib_dmi_quirk) {
1541 			.ignore_wake = "INT33FC:02@28",
1542 		},
1543 	},
1544 	{
1545 		/*
1546 		 * HP X2 10 models with Cherry Trail SoC + AXP288 PMIC use an
1547 		 * external embedded-controller connected via I2C + an ACPI GPIO
1548 		 * event handler on INT33FF:01 pin 0, causing spurious wakeups.
1549 		 */
1550 		.matches = {
1551 			DMI_MATCH(DMI_SYS_VENDOR, "HP"),
1552 			DMI_MATCH(DMI_PRODUCT_NAME, "HP Pavilion x2 Detachable"),
1553 			DMI_MATCH(DMI_BOARD_NAME, "813E"),
1554 		},
1555 		.driver_data = &(struct acpi_gpiolib_dmi_quirk) {
1556 			.ignore_wake = "INT33FF:01@0",
1557 		},
1558 	},
1559 	{} /* Terminating entry */
1560 };
1561 
1562 static int __init acpi_gpio_setup_params(void)
1563 {
1564 	const struct acpi_gpiolib_dmi_quirk *quirk = NULL;
1565 	const struct dmi_system_id *id;
1566 
1567 	id = dmi_first_match(gpiolib_acpi_quirks);
1568 	if (id)
1569 		quirk = id->driver_data;
1570 
1571 	if (run_edge_events_on_boot < 0) {
1572 		if (quirk && quirk->no_edge_events_on_boot)
1573 			run_edge_events_on_boot = 0;
1574 		else
1575 			run_edge_events_on_boot = 1;
1576 	}
1577 
1578 	if (ignore_wake == NULL && quirk && quirk->ignore_wake)
1579 		ignore_wake = quirk->ignore_wake;
1580 
1581 	return 0;
1582 }
1583 
1584 /* Directly after dmi_setup() which runs as core_initcall() */
1585 postcore_initcall(acpi_gpio_setup_params);
1586