xref: /openbmc/linux/drivers/gpio/gpiolib-acpi.c (revision 09717af7)
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 	int ret, value;
223 
224 	ret = request_threaded_irq(event->irq, NULL, event->handler,
225 				   event->irqflags | IRQF_ONESHOT, "ACPI:Event", event);
226 	if (ret) {
227 		dev_err(acpi_gpio->chip->parent,
228 			"Failed to setup interrupt handler for %d\n",
229 			event->irq);
230 		return;
231 	}
232 
233 	if (event->irq_is_wake)
234 		enable_irq_wake(event->irq);
235 
236 	event->irq_requested = true;
237 
238 	/* Make sure we trigger the initial state of edge-triggered IRQs */
239 	if (run_edge_events_on_boot &&
240 	    (event->irqflags & (IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING))) {
241 		value = gpiod_get_raw_value_cansleep(event->desc);
242 		if (((event->irqflags & IRQF_TRIGGER_RISING) && value == 1) ||
243 		    ((event->irqflags & IRQF_TRIGGER_FALLING) && value == 0))
244 			event->handler(event->irq, event);
245 	}
246 }
247 
248 static void acpi_gpiochip_request_irqs(struct acpi_gpio_chip *acpi_gpio)
249 {
250 	struct acpi_gpio_event *event;
251 
252 	list_for_each_entry(event, &acpi_gpio->events, node)
253 		acpi_gpiochip_request_irq(acpi_gpio, event);
254 }
255 
256 static enum gpiod_flags
257 acpi_gpio_to_gpiod_flags(const struct acpi_resource_gpio *agpio, int polarity)
258 {
259 	/* GpioInt() implies input configuration */
260 	if (agpio->connection_type == ACPI_RESOURCE_GPIO_TYPE_INT)
261 		return GPIOD_IN;
262 
263 	switch (agpio->io_restriction) {
264 	case ACPI_IO_RESTRICT_INPUT:
265 		return GPIOD_IN;
266 	case ACPI_IO_RESTRICT_OUTPUT:
267 		/*
268 		 * ACPI GPIO resources don't contain an initial value for the
269 		 * GPIO. Therefore we deduce that value from the pull field
270 		 * and the polarity instead. If the pin is pulled up we assume
271 		 * default to be high, if it is pulled down we assume default
272 		 * to be low, otherwise we leave pin untouched. For active low
273 		 * polarity values will be switched. See also
274 		 * Documentation/firmware-guide/acpi/gpio-properties.rst.
275 		 */
276 		switch (agpio->pin_config) {
277 		case ACPI_PIN_CONFIG_PULLUP:
278 			return polarity == GPIO_ACTIVE_LOW ? GPIOD_OUT_LOW : GPIOD_OUT_HIGH;
279 		case ACPI_PIN_CONFIG_PULLDOWN:
280 			return polarity == GPIO_ACTIVE_LOW ? GPIOD_OUT_HIGH : GPIOD_OUT_LOW;
281 		default:
282 			break;
283 		}
284 		break;
285 	default:
286 		break;
287 	}
288 
289 	/*
290 	 * Assume that the BIOS has configured the direction and pull
291 	 * accordingly.
292 	 */
293 	return GPIOD_ASIS;
294 }
295 
296 static struct gpio_desc *acpi_request_own_gpiod(struct gpio_chip *chip,
297 						struct acpi_resource_gpio *agpio,
298 						unsigned int index,
299 						const char *label)
300 {
301 	int polarity = GPIO_ACTIVE_HIGH;
302 	enum gpiod_flags flags = acpi_gpio_to_gpiod_flags(agpio, polarity);
303 	unsigned int pin = agpio->pin_table[index];
304 	struct gpio_desc *desc;
305 	int ret;
306 
307 	desc = gpiochip_request_own_desc(chip, pin, label, polarity, flags);
308 	if (IS_ERR(desc))
309 		return desc;
310 
311 	ret = gpio_set_debounce_timeout(desc, agpio->debounce_timeout);
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",
351 		    ignore_wake);
352 	return false;
353 }
354 
355 static bool acpi_gpio_irq_is_wake(struct device *parent,
356 				  struct acpi_resource_gpio *agpio)
357 {
358 	int pin = agpio->pin_table[0];
359 
360 	if (agpio->wake_capable != ACPI_WAKE_CAPABLE)
361 		return false;
362 
363 	if (acpi_gpio_in_ignore_list(dev_name(parent), pin)) {
364 		dev_info(parent, "Ignoring wakeup on pin %d\n", pin);
365 		return false;
366 	}
367 
368 	return true;
369 }
370 
371 /* Always returns AE_OK so that we keep looping over the resources */
372 static acpi_status acpi_gpiochip_alloc_event(struct acpi_resource *ares,
373 					     void *context)
374 {
375 	struct acpi_gpio_chip *acpi_gpio = context;
376 	struct gpio_chip *chip = acpi_gpio->chip;
377 	struct acpi_resource_gpio *agpio;
378 	acpi_handle handle, evt_handle;
379 	struct acpi_gpio_event *event;
380 	irq_handler_t handler = NULL;
381 	struct gpio_desc *desc;
382 	int ret, pin, irq;
383 
384 	if (!acpi_gpio_get_irq_resource(ares, &agpio))
385 		return AE_OK;
386 
387 	handle = ACPI_HANDLE(chip->parent);
388 	pin = agpio->pin_table[0];
389 
390 	if (pin <= 255) {
391 		char ev_name[5];
392 		sprintf(ev_name, "_%c%02hhX",
393 			agpio->triggering == ACPI_EDGE_SENSITIVE ? 'E' : 'L',
394 			pin);
395 		if (ACPI_SUCCESS(acpi_get_handle(handle, ev_name, &evt_handle)))
396 			handler = acpi_gpio_irq_handler;
397 	}
398 	if (!handler) {
399 		if (ACPI_SUCCESS(acpi_get_handle(handle, "_EVT", &evt_handle)))
400 			handler = acpi_gpio_irq_handler_evt;
401 	}
402 	if (!handler)
403 		return AE_OK;
404 
405 	desc = acpi_request_own_gpiod(chip, agpio, 0, "ACPI:Event");
406 	if (IS_ERR(desc)) {
407 		dev_err(chip->parent,
408 			"Failed to request GPIO for pin 0x%04X, err %ld\n",
409 			pin, PTR_ERR(desc));
410 		return AE_OK;
411 	}
412 
413 	ret = gpiochip_lock_as_irq(chip, pin);
414 	if (ret) {
415 		dev_err(chip->parent,
416 			"Failed to lock GPIO pin 0x%04X as interrupt, err %d\n",
417 			pin, ret);
418 		goto fail_free_desc;
419 	}
420 
421 	irq = gpiod_to_irq(desc);
422 	if (irq < 0) {
423 		dev_err(chip->parent,
424 			"Failed to translate GPIO pin 0x%04X to IRQ, err %d\n",
425 			pin, irq);
426 		goto fail_unlock_irq;
427 	}
428 
429 	event = kzalloc(sizeof(*event), GFP_KERNEL);
430 	if (!event)
431 		goto fail_unlock_irq;
432 
433 	event->irqflags = IRQF_ONESHOT;
434 	if (agpio->triggering == ACPI_LEVEL_SENSITIVE) {
435 		if (agpio->polarity == ACPI_ACTIVE_HIGH)
436 			event->irqflags |= IRQF_TRIGGER_HIGH;
437 		else
438 			event->irqflags |= IRQF_TRIGGER_LOW;
439 	} else {
440 		switch (agpio->polarity) {
441 		case ACPI_ACTIVE_HIGH:
442 			event->irqflags |= IRQF_TRIGGER_RISING;
443 			break;
444 		case ACPI_ACTIVE_LOW:
445 			event->irqflags |= IRQF_TRIGGER_FALLING;
446 			break;
447 		default:
448 			event->irqflags |= IRQF_TRIGGER_RISING |
449 					   IRQF_TRIGGER_FALLING;
450 			break;
451 		}
452 	}
453 
454 	event->handle = evt_handle;
455 	event->handler = handler;
456 	event->irq = irq;
457 	event->irq_is_wake = acpi_gpio_irq_is_wake(chip->parent, agpio);
458 	event->pin = pin;
459 	event->desc = desc;
460 
461 	list_add_tail(&event->node, &acpi_gpio->events);
462 
463 	return AE_OK;
464 
465 fail_unlock_irq:
466 	gpiochip_unlock_as_irq(chip, pin);
467 fail_free_desc:
468 	gpiochip_free_own_desc(desc);
469 
470 	return AE_OK;
471 }
472 
473 /**
474  * acpi_gpiochip_request_interrupts() - Register isr for gpio chip ACPI events
475  * @chip:      GPIO chip
476  *
477  * ACPI5 platforms can use GPIO signaled ACPI events. These GPIO interrupts are
478  * handled by ACPI event methods which need to be called from the GPIO
479  * chip's interrupt handler. acpi_gpiochip_request_interrupts() finds out which
480  * GPIO pins have ACPI event methods and assigns interrupt handlers that calls
481  * the ACPI event methods for those pins.
482  */
483 void acpi_gpiochip_request_interrupts(struct gpio_chip *chip)
484 {
485 	struct acpi_gpio_chip *acpi_gpio;
486 	acpi_handle handle;
487 	acpi_status status;
488 	bool defer;
489 
490 	if (!chip->parent || !chip->to_irq)
491 		return;
492 
493 	handle = ACPI_HANDLE(chip->parent);
494 	if (!handle)
495 		return;
496 
497 	status = acpi_get_data(handle, acpi_gpio_chip_dh, (void **)&acpi_gpio);
498 	if (ACPI_FAILURE(status))
499 		return;
500 
501 	acpi_walk_resources(handle, "_AEI",
502 			    acpi_gpiochip_alloc_event, acpi_gpio);
503 
504 	mutex_lock(&acpi_gpio_deferred_req_irqs_lock);
505 	defer = !acpi_gpio_deferred_req_irqs_done;
506 	if (defer)
507 		list_add(&acpi_gpio->deferred_req_irqs_list_entry,
508 			 &acpi_gpio_deferred_req_irqs_list);
509 	mutex_unlock(&acpi_gpio_deferred_req_irqs_lock);
510 
511 	if (defer)
512 		return;
513 
514 	acpi_gpiochip_request_irqs(acpi_gpio);
515 }
516 EXPORT_SYMBOL_GPL(acpi_gpiochip_request_interrupts);
517 
518 /**
519  * acpi_gpiochip_free_interrupts() - Free GPIO ACPI event interrupts.
520  * @chip:      GPIO chip
521  *
522  * Free interrupts associated with GPIO ACPI event method for the given
523  * GPIO chip.
524  */
525 void acpi_gpiochip_free_interrupts(struct gpio_chip *chip)
526 {
527 	struct acpi_gpio_chip *acpi_gpio;
528 	struct acpi_gpio_event *event, *ep;
529 	acpi_handle handle;
530 	acpi_status status;
531 
532 	if (!chip->parent || !chip->to_irq)
533 		return;
534 
535 	handle = ACPI_HANDLE(chip->parent);
536 	if (!handle)
537 		return;
538 
539 	status = acpi_get_data(handle, acpi_gpio_chip_dh, (void **)&acpi_gpio);
540 	if (ACPI_FAILURE(status))
541 		return;
542 
543 	mutex_lock(&acpi_gpio_deferred_req_irqs_lock);
544 	if (!list_empty(&acpi_gpio->deferred_req_irqs_list_entry))
545 		list_del_init(&acpi_gpio->deferred_req_irqs_list_entry);
546 	mutex_unlock(&acpi_gpio_deferred_req_irqs_lock);
547 
548 	list_for_each_entry_safe_reverse(event, ep, &acpi_gpio->events, node) {
549 		if (event->irq_requested) {
550 			if (event->irq_is_wake)
551 				disable_irq_wake(event->irq);
552 
553 			free_irq(event->irq, event);
554 		}
555 
556 		gpiochip_unlock_as_irq(chip, event->pin);
557 		gpiochip_free_own_desc(event->desc);
558 		list_del(&event->node);
559 		kfree(event);
560 	}
561 }
562 EXPORT_SYMBOL_GPL(acpi_gpiochip_free_interrupts);
563 
564 int acpi_dev_add_driver_gpios(struct acpi_device *adev,
565 			      const struct acpi_gpio_mapping *gpios)
566 {
567 	if (adev && gpios) {
568 		adev->driver_gpios = gpios;
569 		return 0;
570 	}
571 	return -EINVAL;
572 }
573 EXPORT_SYMBOL_GPL(acpi_dev_add_driver_gpios);
574 
575 void acpi_dev_remove_driver_gpios(struct acpi_device *adev)
576 {
577 	if (adev)
578 		adev->driver_gpios = NULL;
579 }
580 EXPORT_SYMBOL_GPL(acpi_dev_remove_driver_gpios);
581 
582 static void devm_acpi_dev_release_driver_gpios(struct device *dev, void *res)
583 {
584 	acpi_dev_remove_driver_gpios(ACPI_COMPANION(dev));
585 }
586 
587 int devm_acpi_dev_add_driver_gpios(struct device *dev,
588 				   const struct acpi_gpio_mapping *gpios)
589 {
590 	void *res;
591 	int ret;
592 
593 	res = devres_alloc(devm_acpi_dev_release_driver_gpios, 0, GFP_KERNEL);
594 	if (!res)
595 		return -ENOMEM;
596 
597 	ret = acpi_dev_add_driver_gpios(ACPI_COMPANION(dev), gpios);
598 	if (ret) {
599 		devres_free(res);
600 		return ret;
601 	}
602 	devres_add(dev, res);
603 	return 0;
604 }
605 EXPORT_SYMBOL_GPL(devm_acpi_dev_add_driver_gpios);
606 
607 void devm_acpi_dev_remove_driver_gpios(struct device *dev)
608 {
609 	WARN_ON(devres_release(dev, devm_acpi_dev_release_driver_gpios, NULL, NULL));
610 }
611 EXPORT_SYMBOL_GPL(devm_acpi_dev_remove_driver_gpios);
612 
613 static bool acpi_get_driver_gpio_data(struct acpi_device *adev,
614 				      const char *name, int index,
615 				      struct fwnode_reference_args *args,
616 				      unsigned int *quirks)
617 {
618 	const struct acpi_gpio_mapping *gm;
619 
620 	if (!adev->driver_gpios)
621 		return false;
622 
623 	for (gm = adev->driver_gpios; gm->name; gm++)
624 		if (!strcmp(name, gm->name) && gm->data && index < gm->size) {
625 			const struct acpi_gpio_params *par = gm->data + index;
626 
627 			args->fwnode = acpi_fwnode_handle(adev);
628 			args->args[0] = par->crs_entry_index;
629 			args->args[1] = par->line_index;
630 			args->args[2] = par->active_low;
631 			args->nargs = 3;
632 
633 			*quirks = gm->quirks;
634 			return true;
635 		}
636 
637 	return false;
638 }
639 
640 static int
641 __acpi_gpio_update_gpiod_flags(enum gpiod_flags *flags, enum gpiod_flags update)
642 {
643 	const enum gpiod_flags mask =
644 		GPIOD_FLAGS_BIT_DIR_SET | GPIOD_FLAGS_BIT_DIR_OUT |
645 		GPIOD_FLAGS_BIT_DIR_VAL;
646 	int ret = 0;
647 
648 	/*
649 	 * Check if the BIOS has IoRestriction with explicitly set direction
650 	 * and update @flags accordingly. Otherwise use whatever caller asked
651 	 * for.
652 	 */
653 	if (update & GPIOD_FLAGS_BIT_DIR_SET) {
654 		enum gpiod_flags diff = *flags ^ update;
655 
656 		/*
657 		 * Check if caller supplied incompatible GPIO initialization
658 		 * flags.
659 		 *
660 		 * Return %-EINVAL to notify that firmware has different
661 		 * settings and we are going to use them.
662 		 */
663 		if (((*flags & GPIOD_FLAGS_BIT_DIR_SET) && (diff & GPIOD_FLAGS_BIT_DIR_OUT)) ||
664 		    ((*flags & GPIOD_FLAGS_BIT_DIR_OUT) && (diff & GPIOD_FLAGS_BIT_DIR_VAL)))
665 			ret = -EINVAL;
666 		*flags = (*flags & ~mask) | (update & mask);
667 	}
668 	return ret;
669 }
670 
671 int
672 acpi_gpio_update_gpiod_flags(enum gpiod_flags *flags, struct acpi_gpio_info *info)
673 {
674 	struct device *dev = &info->adev->dev;
675 	enum gpiod_flags old = *flags;
676 	int ret;
677 
678 	ret = __acpi_gpio_update_gpiod_flags(&old, info->flags);
679 	if (info->quirks & ACPI_GPIO_QUIRK_NO_IO_RESTRICTION) {
680 		if (ret)
681 			dev_warn(dev, FW_BUG "GPIO not in correct mode, fixing\n");
682 	} else {
683 		if (ret)
684 			dev_dbg(dev, "Override GPIO initialization flags\n");
685 		*flags = old;
686 	}
687 
688 	return ret;
689 }
690 
691 int acpi_gpio_update_gpiod_lookup_flags(unsigned long *lookupflags,
692 					struct acpi_gpio_info *info)
693 {
694 	switch (info->pin_config) {
695 	case ACPI_PIN_CONFIG_PULLUP:
696 		*lookupflags |= GPIO_PULL_UP;
697 		break;
698 	case ACPI_PIN_CONFIG_PULLDOWN:
699 		*lookupflags |= GPIO_PULL_DOWN;
700 		break;
701 	default:
702 		break;
703 	}
704 
705 	if (info->polarity == GPIO_ACTIVE_LOW)
706 		*lookupflags |= GPIO_ACTIVE_LOW;
707 
708 	return 0;
709 }
710 
711 struct acpi_gpio_lookup {
712 	struct acpi_gpio_info info;
713 	int index;
714 	u16 pin_index;
715 	bool active_low;
716 	struct gpio_desc *desc;
717 	int n;
718 };
719 
720 static int acpi_populate_gpio_lookup(struct acpi_resource *ares, void *data)
721 {
722 	struct acpi_gpio_lookup *lookup = data;
723 
724 	if (ares->type != ACPI_RESOURCE_TYPE_GPIO)
725 		return 1;
726 
727 	if (!lookup->desc) {
728 		const struct acpi_resource_gpio *agpio = &ares->data.gpio;
729 		bool gpioint = agpio->connection_type == ACPI_RESOURCE_GPIO_TYPE_INT;
730 		struct gpio_desc *desc;
731 		u16 pin_index;
732 
733 		if (lookup->info.quirks & ACPI_GPIO_QUIRK_ONLY_GPIOIO && gpioint)
734 			lookup->index++;
735 
736 		if (lookup->n++ != lookup->index)
737 			return 1;
738 
739 		pin_index = lookup->pin_index;
740 		if (pin_index >= agpio->pin_table_length)
741 			return 1;
742 
743 		if (lookup->info.quirks & ACPI_GPIO_QUIRK_ABSOLUTE_NUMBER)
744 			desc = gpio_to_desc(agpio->pin_table[pin_index]);
745 		else
746 			desc = acpi_get_gpiod(agpio->resource_source.string_ptr,
747 					      agpio->pin_table[pin_index]);
748 		lookup->desc = desc;
749 		lookup->info.pin_config = agpio->pin_config;
750 		lookup->info.debounce = agpio->debounce_timeout;
751 		lookup->info.gpioint = gpioint;
752 
753 		/*
754 		 * Polarity and triggering are only specified for GpioInt
755 		 * resource.
756 		 * Note: we expect here:
757 		 * - ACPI_ACTIVE_LOW == GPIO_ACTIVE_LOW
758 		 * - ACPI_ACTIVE_HIGH == GPIO_ACTIVE_HIGH
759 		 */
760 		if (lookup->info.gpioint) {
761 			lookup->info.polarity = agpio->polarity;
762 			lookup->info.triggering = agpio->triggering;
763 		} else {
764 			lookup->info.polarity = lookup->active_low;
765 		}
766 
767 		lookup->info.flags = acpi_gpio_to_gpiod_flags(agpio, lookup->info.polarity);
768 	}
769 
770 	return 1;
771 }
772 
773 static int acpi_gpio_resource_lookup(struct acpi_gpio_lookup *lookup,
774 				     struct acpi_gpio_info *info)
775 {
776 	struct acpi_device *adev = lookup->info.adev;
777 	struct list_head res_list;
778 	int ret;
779 
780 	INIT_LIST_HEAD(&res_list);
781 
782 	ret = acpi_dev_get_resources(adev, &res_list,
783 				     acpi_populate_gpio_lookup,
784 				     lookup);
785 	if (ret < 0)
786 		return ret;
787 
788 	acpi_dev_free_resource_list(&res_list);
789 
790 	if (!lookup->desc)
791 		return -ENOENT;
792 
793 	if (info)
794 		*info = lookup->info;
795 	return 0;
796 }
797 
798 static int acpi_gpio_property_lookup(struct fwnode_handle *fwnode,
799 				     const char *propname, int index,
800 				     struct acpi_gpio_lookup *lookup)
801 {
802 	struct fwnode_reference_args args;
803 	unsigned int quirks = 0;
804 	int ret;
805 
806 	memset(&args, 0, sizeof(args));
807 	ret = __acpi_node_get_property_reference(fwnode, propname, index, 3,
808 						 &args);
809 	if (ret) {
810 		struct acpi_device *adev = to_acpi_device_node(fwnode);
811 
812 		if (!adev)
813 			return ret;
814 
815 		if (!acpi_get_driver_gpio_data(adev, propname, index, &args,
816 					       &quirks))
817 			return ret;
818 	}
819 	/*
820 	 * The property was found and resolved, so need to lookup the GPIO based
821 	 * on returned args.
822 	 */
823 	if (!to_acpi_device_node(args.fwnode))
824 		return -EINVAL;
825 	if (args.nargs != 3)
826 		return -EPROTO;
827 
828 	lookup->index = args.args[0];
829 	lookup->pin_index = args.args[1];
830 	lookup->active_low = !!args.args[2];
831 
832 	lookup->info.adev = to_acpi_device_node(args.fwnode);
833 	lookup->info.quirks = quirks;
834 
835 	return 0;
836 }
837 
838 /**
839  * acpi_get_gpiod_by_index() - get a GPIO descriptor from device resources
840  * @adev: pointer to a ACPI device to get GPIO from
841  * @propname: Property name of the GPIO (optional)
842  * @index: index of GpioIo/GpioInt resource (starting from %0)
843  * @info: info pointer to fill in (optional)
844  *
845  * Function goes through ACPI resources for @adev and based on @index looks
846  * up a GpioIo/GpioInt resource, translates it to the Linux GPIO descriptor,
847  * and returns it. @index matches GpioIo/GpioInt resources only so if there
848  * are total %3 GPIO resources, the index goes from %0 to %2.
849  *
850  * If @propname is specified the GPIO is looked using device property. In
851  * that case @index is used to select the GPIO entry in the property value
852  * (in case of multiple).
853  *
854  * If the GPIO cannot be translated or there is an error, an ERR_PTR is
855  * returned.
856  *
857  * Note: if the GPIO resource has multiple entries in the pin list, this
858  * function only returns the first.
859  */
860 static struct gpio_desc *acpi_get_gpiod_by_index(struct acpi_device *adev,
861 					  const char *propname, int index,
862 					  struct acpi_gpio_info *info)
863 {
864 	struct acpi_gpio_lookup lookup;
865 	int ret;
866 
867 	if (!adev)
868 		return ERR_PTR(-ENODEV);
869 
870 	memset(&lookup, 0, sizeof(lookup));
871 	lookup.index = index;
872 
873 	if (propname) {
874 		dev_dbg(&adev->dev, "GPIO: looking up %s\n", propname);
875 
876 		ret = acpi_gpio_property_lookup(acpi_fwnode_handle(adev),
877 						propname, index, &lookup);
878 		if (ret)
879 			return ERR_PTR(ret);
880 
881 		dev_dbg(&adev->dev, "GPIO: _DSD returned %s %d %u %u\n",
882 			dev_name(&lookup.info.adev->dev), lookup.index,
883 			lookup.pin_index, lookup.active_low);
884 	} else {
885 		dev_dbg(&adev->dev, "GPIO: looking up %d in _CRS\n", index);
886 		lookup.info.adev = adev;
887 	}
888 
889 	ret = acpi_gpio_resource_lookup(&lookup, info);
890 	return ret ? ERR_PTR(ret) : lookup.desc;
891 }
892 
893 static bool acpi_can_fallback_to_crs(struct acpi_device *adev,
894 				     const char *con_id)
895 {
896 	/* Never allow fallback if the device has properties */
897 	if (acpi_dev_has_props(adev) || adev->driver_gpios)
898 		return false;
899 
900 	return con_id == NULL;
901 }
902 
903 struct gpio_desc *acpi_find_gpio(struct device *dev,
904 				 const char *con_id,
905 				 unsigned int idx,
906 				 enum gpiod_flags *dflags,
907 				 unsigned long *lookupflags)
908 {
909 	struct acpi_device *adev = ACPI_COMPANION(dev);
910 	struct acpi_gpio_info info;
911 	struct gpio_desc *desc;
912 	char propname[32];
913 	int i;
914 
915 	/* Try first from _DSD */
916 	for (i = 0; i < ARRAY_SIZE(gpio_suffixes); i++) {
917 		if (con_id) {
918 			snprintf(propname, sizeof(propname), "%s-%s",
919 				 con_id, gpio_suffixes[i]);
920 		} else {
921 			snprintf(propname, sizeof(propname), "%s",
922 				 gpio_suffixes[i]);
923 		}
924 
925 		desc = acpi_get_gpiod_by_index(adev, propname, idx, &info);
926 		if (!IS_ERR(desc))
927 			break;
928 		if (PTR_ERR(desc) == -EPROBE_DEFER)
929 			return ERR_CAST(desc);
930 	}
931 
932 	/* Then from plain _CRS GPIOs */
933 	if (IS_ERR(desc)) {
934 		if (!acpi_can_fallback_to_crs(adev, con_id))
935 			return ERR_PTR(-ENOENT);
936 
937 		desc = acpi_get_gpiod_by_index(adev, NULL, idx, &info);
938 		if (IS_ERR(desc))
939 			return desc;
940 	}
941 
942 	if (info.gpioint &&
943 	    (*dflags == GPIOD_OUT_LOW || *dflags == GPIOD_OUT_HIGH)) {
944 		dev_dbg(dev, "refusing GpioInt() entry when doing GPIOD_OUT_* lookup\n");
945 		return ERR_PTR(-ENOENT);
946 	}
947 
948 	acpi_gpio_update_gpiod_flags(dflags, &info);
949 	acpi_gpio_update_gpiod_lookup_flags(lookupflags, &info);
950 	return desc;
951 }
952 
953 /**
954  * acpi_node_get_gpiod() - get a GPIO descriptor from ACPI resources
955  * @fwnode: pointer to an ACPI firmware node to get the GPIO information from
956  * @propname: Property name of the GPIO
957  * @index: index of GpioIo/GpioInt resource (starting from %0)
958  * @info: info pointer to fill in (optional)
959  *
960  * If @fwnode is an ACPI device object, call acpi_get_gpiod_by_index() for it.
961  * Otherwise (i.e. it is a data-only non-device object), use the property-based
962  * GPIO lookup to get to the GPIO resource with the relevant information and use
963  * that to obtain the GPIO descriptor to return.
964  *
965  * If the GPIO cannot be translated or there is an error an ERR_PTR is
966  * returned.
967  */
968 struct gpio_desc *acpi_node_get_gpiod(struct fwnode_handle *fwnode,
969 				      const char *propname, int index,
970 				      struct acpi_gpio_info *info)
971 {
972 	struct acpi_gpio_lookup lookup;
973 	struct acpi_device *adev;
974 	int ret;
975 
976 	adev = to_acpi_device_node(fwnode);
977 	if (adev)
978 		return acpi_get_gpiod_by_index(adev, propname, index, info);
979 
980 	if (!is_acpi_data_node(fwnode))
981 		return ERR_PTR(-ENODEV);
982 
983 	if (!propname)
984 		return ERR_PTR(-EINVAL);
985 
986 	memset(&lookup, 0, sizeof(lookup));
987 	lookup.index = index;
988 
989 	ret = acpi_gpio_property_lookup(fwnode, propname, index, &lookup);
990 	if (ret)
991 		return ERR_PTR(ret);
992 
993 	ret = acpi_gpio_resource_lookup(&lookup, info);
994 	return ret ? ERR_PTR(ret) : lookup.desc;
995 }
996 
997 /**
998  * acpi_dev_gpio_irq_get_by() - Find GpioInt and translate it to Linux IRQ number
999  * @adev: pointer to a ACPI device to get IRQ from
1000  * @name: optional name of GpioInt resource
1001  * @index: index of GpioInt resource (starting from %0)
1002  *
1003  * If the device has one or more GpioInt resources, this function can be
1004  * used to translate from the GPIO offset in the resource to the Linux IRQ
1005  * number.
1006  *
1007  * The function is idempotent, though each time it runs it will configure GPIO
1008  * pin direction according to the flags in GpioInt resource.
1009  *
1010  * The function takes optional @name parameter. If the resource has a property
1011  * name, then only those will be taken into account.
1012  *
1013  * Return: Linux IRQ number (> %0) on success, negative errno on failure.
1014  */
1015 int acpi_dev_gpio_irq_get_by(struct acpi_device *adev, const char *name, int index)
1016 {
1017 	int idx, i;
1018 	unsigned int irq_flags;
1019 	int ret;
1020 
1021 	for (i = 0, idx = 0; idx <= index; i++) {
1022 		struct acpi_gpio_info info;
1023 		struct gpio_desc *desc;
1024 
1025 		desc = acpi_get_gpiod_by_index(adev, name, i, &info);
1026 
1027 		/* Ignore -EPROBE_DEFER, it only matters if idx matches */
1028 		if (IS_ERR(desc) && PTR_ERR(desc) != -EPROBE_DEFER)
1029 			return PTR_ERR(desc);
1030 
1031 		if (info.gpioint && idx++ == index) {
1032 			unsigned long lflags = GPIO_LOOKUP_FLAGS_DEFAULT;
1033 			enum gpiod_flags dflags = GPIOD_ASIS;
1034 			char label[32];
1035 			int irq;
1036 
1037 			if (IS_ERR(desc))
1038 				return PTR_ERR(desc);
1039 
1040 			irq = gpiod_to_irq(desc);
1041 			if (irq < 0)
1042 				return irq;
1043 
1044 			acpi_gpio_update_gpiod_flags(&dflags, &info);
1045 			acpi_gpio_update_gpiod_lookup_flags(&lflags, &info);
1046 
1047 			snprintf(label, sizeof(label), "GpioInt() %d", index);
1048 			ret = gpiod_configure_flags(desc, label, lflags, dflags);
1049 			if (ret < 0)
1050 				return ret;
1051 
1052 			ret = gpio_set_debounce_timeout(desc, info.debounce);
1053 			if (ret)
1054 				return ret;
1055 
1056 			irq_flags = acpi_dev_get_irq_type(info.triggering,
1057 							  info.polarity);
1058 
1059 			/* Set type if specified and different than the current one */
1060 			if (irq_flags != IRQ_TYPE_NONE &&
1061 			    irq_flags != irq_get_trigger_type(irq))
1062 				irq_set_irq_type(irq, irq_flags);
1063 
1064 			return irq;
1065 		}
1066 
1067 	}
1068 	return -ENOENT;
1069 }
1070 EXPORT_SYMBOL_GPL(acpi_dev_gpio_irq_get_by);
1071 
1072 static acpi_status
1073 acpi_gpio_adr_space_handler(u32 function, acpi_physical_address address,
1074 			    u32 bits, u64 *value, void *handler_context,
1075 			    void *region_context)
1076 {
1077 	struct acpi_gpio_chip *achip = region_context;
1078 	struct gpio_chip *chip = achip->chip;
1079 	struct acpi_resource_gpio *agpio;
1080 	struct acpi_resource *ares;
1081 	u16 pin_index = address;
1082 	acpi_status status;
1083 	int length;
1084 	int i;
1085 
1086 	status = acpi_buffer_to_resource(achip->conn_info.connection,
1087 					 achip->conn_info.length, &ares);
1088 	if (ACPI_FAILURE(status))
1089 		return status;
1090 
1091 	if (WARN_ON(ares->type != ACPI_RESOURCE_TYPE_GPIO)) {
1092 		ACPI_FREE(ares);
1093 		return AE_BAD_PARAMETER;
1094 	}
1095 
1096 	agpio = &ares->data.gpio;
1097 
1098 	if (WARN_ON(agpio->io_restriction == ACPI_IO_RESTRICT_INPUT &&
1099 	    function == ACPI_WRITE)) {
1100 		ACPI_FREE(ares);
1101 		return AE_BAD_PARAMETER;
1102 	}
1103 
1104 	length = min_t(u16, agpio->pin_table_length, pin_index + bits);
1105 	for (i = pin_index; i < length; ++i) {
1106 		int pin = agpio->pin_table[i];
1107 		struct acpi_gpio_connection *conn;
1108 		struct gpio_desc *desc;
1109 		bool found;
1110 
1111 		mutex_lock(&achip->conn_lock);
1112 
1113 		found = false;
1114 		list_for_each_entry(conn, &achip->conns, node) {
1115 			if (conn->pin == pin) {
1116 				found = true;
1117 				desc = conn->desc;
1118 				break;
1119 			}
1120 		}
1121 
1122 		/*
1123 		 * The same GPIO can be shared between operation region and
1124 		 * event but only if the access here is ACPI_READ. In that
1125 		 * case we "borrow" the event GPIO instead.
1126 		 */
1127 		if (!found && agpio->shareable == ACPI_SHARED &&
1128 		     function == ACPI_READ) {
1129 			struct acpi_gpio_event *event;
1130 
1131 			list_for_each_entry(event, &achip->events, node) {
1132 				if (event->pin == pin) {
1133 					desc = event->desc;
1134 					found = true;
1135 					break;
1136 				}
1137 			}
1138 		}
1139 
1140 		if (!found) {
1141 			desc = acpi_request_own_gpiod(chip, agpio, i, "ACPI:OpRegion");
1142 			if (IS_ERR(desc)) {
1143 				mutex_unlock(&achip->conn_lock);
1144 				status = AE_ERROR;
1145 				goto out;
1146 			}
1147 
1148 			conn = kzalloc(sizeof(*conn), GFP_KERNEL);
1149 			if (!conn) {
1150 				gpiochip_free_own_desc(desc);
1151 				mutex_unlock(&achip->conn_lock);
1152 				status = AE_NO_MEMORY;
1153 				goto out;
1154 			}
1155 
1156 			conn->pin = pin;
1157 			conn->desc = desc;
1158 			list_add_tail(&conn->node, &achip->conns);
1159 		}
1160 
1161 		mutex_unlock(&achip->conn_lock);
1162 
1163 		if (function == ACPI_WRITE)
1164 			gpiod_set_raw_value_cansleep(desc, !!(*value & BIT(i)));
1165 		else
1166 			*value |= (u64)gpiod_get_raw_value_cansleep(desc) << i;
1167 	}
1168 
1169 out:
1170 	ACPI_FREE(ares);
1171 	return status;
1172 }
1173 
1174 static void acpi_gpiochip_request_regions(struct acpi_gpio_chip *achip)
1175 {
1176 	struct gpio_chip *chip = achip->chip;
1177 	acpi_handle handle = ACPI_HANDLE(chip->parent);
1178 	acpi_status status;
1179 
1180 	INIT_LIST_HEAD(&achip->conns);
1181 	mutex_init(&achip->conn_lock);
1182 	status = acpi_install_address_space_handler(handle, ACPI_ADR_SPACE_GPIO,
1183 						    acpi_gpio_adr_space_handler,
1184 						    NULL, achip);
1185 	if (ACPI_FAILURE(status))
1186 		dev_err(chip->parent,
1187 		        "Failed to install GPIO OpRegion handler\n");
1188 }
1189 
1190 static void acpi_gpiochip_free_regions(struct acpi_gpio_chip *achip)
1191 {
1192 	struct gpio_chip *chip = achip->chip;
1193 	acpi_handle handle = ACPI_HANDLE(chip->parent);
1194 	struct acpi_gpio_connection *conn, *tmp;
1195 	acpi_status status;
1196 
1197 	status = acpi_remove_address_space_handler(handle, ACPI_ADR_SPACE_GPIO,
1198 						   acpi_gpio_adr_space_handler);
1199 	if (ACPI_FAILURE(status)) {
1200 		dev_err(chip->parent,
1201 			"Failed to remove GPIO OpRegion handler\n");
1202 		return;
1203 	}
1204 
1205 	list_for_each_entry_safe_reverse(conn, tmp, &achip->conns, node) {
1206 		gpiochip_free_own_desc(conn->desc);
1207 		list_del(&conn->node);
1208 		kfree(conn);
1209 	}
1210 }
1211 
1212 static struct gpio_desc *
1213 acpi_gpiochip_parse_own_gpio(struct acpi_gpio_chip *achip,
1214 			     struct fwnode_handle *fwnode,
1215 			     const char **name,
1216 			     unsigned long *lflags,
1217 			     enum gpiod_flags *dflags)
1218 {
1219 	struct gpio_chip *chip = achip->chip;
1220 	struct gpio_desc *desc;
1221 	u32 gpios[2];
1222 	int ret;
1223 
1224 	*lflags = GPIO_LOOKUP_FLAGS_DEFAULT;
1225 	*dflags = GPIOD_ASIS;
1226 	*name = NULL;
1227 
1228 	ret = fwnode_property_read_u32_array(fwnode, "gpios", gpios,
1229 					     ARRAY_SIZE(gpios));
1230 	if (ret < 0)
1231 		return ERR_PTR(ret);
1232 
1233 	desc = gpiochip_get_desc(chip, gpios[0]);
1234 	if (IS_ERR(desc))
1235 		return desc;
1236 
1237 	if (gpios[1])
1238 		*lflags |= GPIO_ACTIVE_LOW;
1239 
1240 	if (fwnode_property_present(fwnode, "input"))
1241 		*dflags |= GPIOD_IN;
1242 	else if (fwnode_property_present(fwnode, "output-low"))
1243 		*dflags |= GPIOD_OUT_LOW;
1244 	else if (fwnode_property_present(fwnode, "output-high"))
1245 		*dflags |= GPIOD_OUT_HIGH;
1246 	else
1247 		return ERR_PTR(-EINVAL);
1248 
1249 	fwnode_property_read_string(fwnode, "line-name", name);
1250 
1251 	return desc;
1252 }
1253 
1254 static void acpi_gpiochip_scan_gpios(struct acpi_gpio_chip *achip)
1255 {
1256 	struct gpio_chip *chip = achip->chip;
1257 	struct fwnode_handle *fwnode;
1258 
1259 	device_for_each_child_node(chip->parent, fwnode) {
1260 		unsigned long lflags;
1261 		enum gpiod_flags dflags;
1262 		struct gpio_desc *desc;
1263 		const char *name;
1264 		int ret;
1265 
1266 		if (!fwnode_property_present(fwnode, "gpio-hog"))
1267 			continue;
1268 
1269 		desc = acpi_gpiochip_parse_own_gpio(achip, fwnode, &name,
1270 						    &lflags, &dflags);
1271 		if (IS_ERR(desc))
1272 			continue;
1273 
1274 		ret = gpiod_hog(desc, name, lflags, dflags);
1275 		if (ret) {
1276 			dev_err(chip->parent, "Failed to hog GPIO\n");
1277 			fwnode_handle_put(fwnode);
1278 			return;
1279 		}
1280 	}
1281 }
1282 
1283 void acpi_gpiochip_add(struct gpio_chip *chip)
1284 {
1285 	struct acpi_gpio_chip *acpi_gpio;
1286 	struct acpi_device *adev;
1287 	acpi_status status;
1288 
1289 	if (!chip || !chip->parent)
1290 		return;
1291 
1292 	adev = ACPI_COMPANION(chip->parent);
1293 	if (!adev)
1294 		return;
1295 
1296 	acpi_gpio = kzalloc(sizeof(*acpi_gpio), GFP_KERNEL);
1297 	if (!acpi_gpio) {
1298 		dev_err(chip->parent,
1299 			"Failed to allocate memory for ACPI GPIO chip\n");
1300 		return;
1301 	}
1302 
1303 	acpi_gpio->chip = chip;
1304 	INIT_LIST_HEAD(&acpi_gpio->events);
1305 	INIT_LIST_HEAD(&acpi_gpio->deferred_req_irqs_list_entry);
1306 
1307 	status = acpi_attach_data(adev->handle, acpi_gpio_chip_dh, acpi_gpio);
1308 	if (ACPI_FAILURE(status)) {
1309 		dev_err(chip->parent, "Failed to attach ACPI GPIO chip\n");
1310 		kfree(acpi_gpio);
1311 		return;
1312 	}
1313 
1314 	acpi_gpiochip_request_regions(acpi_gpio);
1315 	acpi_gpiochip_scan_gpios(acpi_gpio);
1316 	acpi_dev_clear_dependencies(adev);
1317 }
1318 
1319 void acpi_gpiochip_remove(struct gpio_chip *chip)
1320 {
1321 	struct acpi_gpio_chip *acpi_gpio;
1322 	acpi_handle handle;
1323 	acpi_status status;
1324 
1325 	if (!chip || !chip->parent)
1326 		return;
1327 
1328 	handle = ACPI_HANDLE(chip->parent);
1329 	if (!handle)
1330 		return;
1331 
1332 	status = acpi_get_data(handle, acpi_gpio_chip_dh, (void **)&acpi_gpio);
1333 	if (ACPI_FAILURE(status)) {
1334 		dev_warn(chip->parent, "Failed to retrieve ACPI GPIO chip\n");
1335 		return;
1336 	}
1337 
1338 	acpi_gpiochip_free_regions(acpi_gpio);
1339 
1340 	acpi_detach_data(handle, acpi_gpio_chip_dh);
1341 	kfree(acpi_gpio);
1342 }
1343 
1344 void acpi_gpio_dev_init(struct gpio_chip *gc, struct gpio_device *gdev)
1345 {
1346 	/* Set default fwnode to parent's one if present */
1347 	if (gc->parent)
1348 		ACPI_COMPANION_SET(&gdev->dev, ACPI_COMPANION(gc->parent));
1349 }
1350 
1351 static int acpi_gpio_package_count(const union acpi_object *obj)
1352 {
1353 	const union acpi_object *element = obj->package.elements;
1354 	const union acpi_object *end = element + obj->package.count;
1355 	unsigned int count = 0;
1356 
1357 	while (element < end) {
1358 		switch (element->type) {
1359 		case ACPI_TYPE_LOCAL_REFERENCE:
1360 			element += 3;
1361 			fallthrough;
1362 		case ACPI_TYPE_INTEGER:
1363 			element++;
1364 			count++;
1365 			break;
1366 
1367 		default:
1368 			return -EPROTO;
1369 		}
1370 	}
1371 
1372 	return count;
1373 }
1374 
1375 static int acpi_find_gpio_count(struct acpi_resource *ares, void *data)
1376 {
1377 	unsigned int *count = data;
1378 
1379 	if (ares->type == ACPI_RESOURCE_TYPE_GPIO)
1380 		*count += ares->data.gpio.pin_table_length;
1381 
1382 	return 1;
1383 }
1384 
1385 /**
1386  * acpi_gpio_count - count the GPIOs associated with a device / function
1387  * @dev:	GPIO consumer, can be %NULL for system-global GPIOs
1388  * @con_id:	function within the GPIO consumer
1389  *
1390  * Return:
1391  * The number of GPIOs associated with a device / function or %-ENOENT,
1392  * if no GPIO has been assigned to the requested function.
1393  */
1394 int acpi_gpio_count(struct device *dev, const char *con_id)
1395 {
1396 	struct acpi_device *adev = ACPI_COMPANION(dev);
1397 	const union acpi_object *obj;
1398 	const struct acpi_gpio_mapping *gm;
1399 	int count = -ENOENT;
1400 	int ret;
1401 	char propname[32];
1402 	unsigned int i;
1403 
1404 	/* Try first from _DSD */
1405 	for (i = 0; i < ARRAY_SIZE(gpio_suffixes); i++) {
1406 		if (con_id)
1407 			snprintf(propname, sizeof(propname), "%s-%s",
1408 				 con_id, gpio_suffixes[i]);
1409 		else
1410 			snprintf(propname, sizeof(propname), "%s",
1411 				 gpio_suffixes[i]);
1412 
1413 		ret = acpi_dev_get_property(adev, propname, ACPI_TYPE_ANY,
1414 					    &obj);
1415 		if (ret == 0) {
1416 			if (obj->type == ACPI_TYPE_LOCAL_REFERENCE)
1417 				count = 1;
1418 			else if (obj->type == ACPI_TYPE_PACKAGE)
1419 				count = acpi_gpio_package_count(obj);
1420 		} else if (adev->driver_gpios) {
1421 			for (gm = adev->driver_gpios; gm->name; gm++)
1422 				if (strcmp(propname, gm->name) == 0) {
1423 					count = gm->size;
1424 					break;
1425 				}
1426 		}
1427 		if (count > 0)
1428 			break;
1429 	}
1430 
1431 	/* Then from plain _CRS GPIOs */
1432 	if (count < 0) {
1433 		struct list_head resource_list;
1434 		unsigned int crs_count = 0;
1435 
1436 		if (!acpi_can_fallback_to_crs(adev, con_id))
1437 			return count;
1438 
1439 		INIT_LIST_HEAD(&resource_list);
1440 		acpi_dev_get_resources(adev, &resource_list,
1441 				       acpi_find_gpio_count, &crs_count);
1442 		acpi_dev_free_resource_list(&resource_list);
1443 		if (crs_count > 0)
1444 			count = crs_count;
1445 	}
1446 	return count ? count : -ENOENT;
1447 }
1448 
1449 /* Run deferred acpi_gpiochip_request_irqs() */
1450 static int __init acpi_gpio_handle_deferred_request_irqs(void)
1451 {
1452 	struct acpi_gpio_chip *acpi_gpio, *tmp;
1453 
1454 	mutex_lock(&acpi_gpio_deferred_req_irqs_lock);
1455 	list_for_each_entry_safe(acpi_gpio, tmp,
1456 				 &acpi_gpio_deferred_req_irqs_list,
1457 				 deferred_req_irqs_list_entry)
1458 		acpi_gpiochip_request_irqs(acpi_gpio);
1459 
1460 	acpi_gpio_deferred_req_irqs_done = true;
1461 	mutex_unlock(&acpi_gpio_deferred_req_irqs_lock);
1462 
1463 	return 0;
1464 }
1465 /* We must use _sync so that this runs after the first deferred_probe run */
1466 late_initcall_sync(acpi_gpio_handle_deferred_request_irqs);
1467 
1468 static const struct dmi_system_id gpiolib_acpi_quirks[] __initconst = {
1469 	{
1470 		/*
1471 		 * The Minix Neo Z83-4 has a micro-USB-B id-pin handler for
1472 		 * a non existing micro-USB-B connector which puts the HDMI
1473 		 * DDC pins in GPIO mode, breaking HDMI support.
1474 		 */
1475 		.matches = {
1476 			DMI_MATCH(DMI_SYS_VENDOR, "MINIX"),
1477 			DMI_MATCH(DMI_PRODUCT_NAME, "Z83-4"),
1478 		},
1479 		.driver_data = &(struct acpi_gpiolib_dmi_quirk) {
1480 			.no_edge_events_on_boot = true,
1481 		},
1482 	},
1483 	{
1484 		/*
1485 		 * The Terra Pad 1061 has a micro-USB-B id-pin handler, which
1486 		 * instead of controlling the actual micro-USB-B turns the 5V
1487 		 * boost for its USB-A connector off. The actual micro-USB-B
1488 		 * connector is wired for charging only.
1489 		 */
1490 		.matches = {
1491 			DMI_MATCH(DMI_SYS_VENDOR, "Wortmann_AG"),
1492 			DMI_MATCH(DMI_PRODUCT_NAME, "TERRA_PAD_1061"),
1493 		},
1494 		.driver_data = &(struct acpi_gpiolib_dmi_quirk) {
1495 			.no_edge_events_on_boot = true,
1496 		},
1497 	},
1498 	{
1499 		/*
1500 		 * The Dell Venue 10 Pro 5055, with Bay Trail SoC + TI PMIC uses an
1501 		 * external embedded-controller connected via I2C + an ACPI GPIO
1502 		 * event handler on INT33FFC:02 pin 12, causing spurious wakeups.
1503 		 */
1504 		.matches = {
1505 			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
1506 			DMI_MATCH(DMI_PRODUCT_NAME, "Venue 10 Pro 5055"),
1507 		},
1508 		.driver_data = &(struct acpi_gpiolib_dmi_quirk) {
1509 			.ignore_wake = "INT33FC:02@12",
1510 		},
1511 	},
1512 	{
1513 		/*
1514 		 * HP X2 10 models with Cherry Trail SoC + TI PMIC use an
1515 		 * external embedded-controller connected via I2C + an ACPI GPIO
1516 		 * event handler on INT33FF:01 pin 0, causing spurious wakeups.
1517 		 * When suspending by closing the LID, the power to the USB
1518 		 * keyboard is turned off, causing INT0002 ACPI events to
1519 		 * trigger once the XHCI controller notices the keyboard is
1520 		 * gone. So INT0002 events cause spurious wakeups too. Ignoring
1521 		 * EC wakes breaks wakeup when opening the lid, the user needs
1522 		 * to press the power-button to wakeup the system. The
1523 		 * alternative is suspend simply not working, which is worse.
1524 		 */
1525 		.matches = {
1526 			DMI_MATCH(DMI_SYS_VENDOR, "HP"),
1527 			DMI_MATCH(DMI_PRODUCT_NAME, "HP x2 Detachable 10-p0XX"),
1528 		},
1529 		.driver_data = &(struct acpi_gpiolib_dmi_quirk) {
1530 			.ignore_wake = "INT33FF:01@0,INT0002:00@2",
1531 		},
1532 	},
1533 	{
1534 		/*
1535 		 * HP X2 10 models with Bay Trail SoC + AXP288 PMIC use an
1536 		 * external embedded-controller connected via I2C + an ACPI GPIO
1537 		 * event handler on INT33FC:02 pin 28, causing spurious wakeups.
1538 		 */
1539 		.matches = {
1540 			DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
1541 			DMI_MATCH(DMI_PRODUCT_NAME, "HP Pavilion x2 Detachable"),
1542 			DMI_MATCH(DMI_BOARD_NAME, "815D"),
1543 		},
1544 		.driver_data = &(struct acpi_gpiolib_dmi_quirk) {
1545 			.ignore_wake = "INT33FC:02@28",
1546 		},
1547 	},
1548 	{
1549 		/*
1550 		 * HP X2 10 models with Cherry Trail SoC + AXP288 PMIC use an
1551 		 * external embedded-controller connected via I2C + an ACPI GPIO
1552 		 * event handler on INT33FF:01 pin 0, causing spurious wakeups.
1553 		 */
1554 		.matches = {
1555 			DMI_MATCH(DMI_SYS_VENDOR, "HP"),
1556 			DMI_MATCH(DMI_PRODUCT_NAME, "HP Pavilion x2 Detachable"),
1557 			DMI_MATCH(DMI_BOARD_NAME, "813E"),
1558 		},
1559 		.driver_data = &(struct acpi_gpiolib_dmi_quirk) {
1560 			.ignore_wake = "INT33FF:01@0",
1561 		},
1562 	},
1563 	{} /* Terminating entry */
1564 };
1565 
1566 static int __init acpi_gpio_setup_params(void)
1567 {
1568 	const struct acpi_gpiolib_dmi_quirk *quirk = NULL;
1569 	const struct dmi_system_id *id;
1570 
1571 	id = dmi_first_match(gpiolib_acpi_quirks);
1572 	if (id)
1573 		quirk = id->driver_data;
1574 
1575 	if (run_edge_events_on_boot < 0) {
1576 		if (quirk && quirk->no_edge_events_on_boot)
1577 			run_edge_events_on_boot = 0;
1578 		else
1579 			run_edge_events_on_boot = 1;
1580 	}
1581 
1582 	if (ignore_wake == NULL && quirk && quirk->ignore_wake)
1583 		ignore_wake = quirk->ignore_wake;
1584 
1585 	return 0;
1586 }
1587 
1588 /* Directly after dmi_setup() which runs as core_initcall() */
1589 postcore_initcall(acpi_gpio_setup_params);
1590