xref: /openbmc/linux/drivers/gpio/gpiolib-acpi.c (revision a9d85efb)
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 	if (!gc->parent)
99 		return false;
100 
101 	return ACPI_HANDLE(gc->parent) == data;
102 }
103 
104 /**
105  * acpi_get_gpiod() - Translate ACPI GPIO pin to GPIO descriptor usable with GPIO API
106  * @path:	ACPI GPIO controller full path name, (e.g. "\\_SB.GPO1")
107  * @pin:	ACPI GPIO pin number (0-based, controller-relative)
108  *
109  * Return: GPIO descriptor to use with Linux generic GPIO API, or ERR_PTR
110  * error value. Specifically returns %-EPROBE_DEFER if the referenced GPIO
111  * controller does not have GPIO chip registered at the moment. This is to
112  * support probe deferral.
113  */
114 static struct gpio_desc *acpi_get_gpiod(char *path, int pin)
115 {
116 	struct gpio_chip *chip;
117 	acpi_handle handle;
118 	acpi_status status;
119 
120 	status = acpi_get_handle(NULL, path, &handle);
121 	if (ACPI_FAILURE(status))
122 		return ERR_PTR(-ENODEV);
123 
124 	chip = gpiochip_find(handle, acpi_gpiochip_find);
125 	if (!chip)
126 		return ERR_PTR(-EPROBE_DEFER);
127 
128 	return gpiochip_get_desc(chip, pin);
129 }
130 
131 /**
132  * acpi_get_and_request_gpiod - Translate ACPI GPIO pin to GPIO descriptor and
133  *                              hold a refcount to the GPIO device.
134  * @path:      ACPI GPIO controller full path name, (e.g. "\\_SB.GPO1")
135  * @pin:       ACPI GPIO pin number (0-based, controller-relative)
136  * @label:     Label to pass to gpiod_request()
137  *
138  * This function is a simple pass-through to acpi_get_gpiod(), except that
139  * as it is intended for use outside of the GPIO layer (in a similar fashion to
140  * gpiod_get_index() for example) it also holds a reference to the GPIO device.
141  */
142 struct gpio_desc *acpi_get_and_request_gpiod(char *path, int pin, char *label)
143 {
144 	struct gpio_desc *gpio;
145 	int ret;
146 
147 	gpio = acpi_get_gpiod(path, pin);
148 	if (IS_ERR(gpio))
149 		return gpio;
150 
151 	ret = gpiod_request(gpio, label);
152 	if (ret)
153 		return ERR_PTR(ret);
154 
155 	return gpio;
156 }
157 EXPORT_SYMBOL_GPL(acpi_get_and_request_gpiod);
158 
159 static irqreturn_t acpi_gpio_irq_handler(int irq, void *data)
160 {
161 	struct acpi_gpio_event *event = data;
162 
163 	acpi_evaluate_object(event->handle, NULL, NULL, NULL);
164 
165 	return IRQ_HANDLED;
166 }
167 
168 static irqreturn_t acpi_gpio_irq_handler_evt(int irq, void *data)
169 {
170 	struct acpi_gpio_event *event = data;
171 
172 	acpi_execute_simple_method(event->handle, NULL, event->pin);
173 
174 	return IRQ_HANDLED;
175 }
176 
177 static void acpi_gpio_chip_dh(acpi_handle handle, void *data)
178 {
179 	/* The address of this function is used as a key. */
180 }
181 
182 bool acpi_gpio_get_irq_resource(struct acpi_resource *ares,
183 				struct acpi_resource_gpio **agpio)
184 {
185 	struct acpi_resource_gpio *gpio;
186 
187 	if (ares->type != ACPI_RESOURCE_TYPE_GPIO)
188 		return false;
189 
190 	gpio = &ares->data.gpio;
191 	if (gpio->connection_type != ACPI_RESOURCE_GPIO_TYPE_INT)
192 		return false;
193 
194 	*agpio = gpio;
195 	return true;
196 }
197 EXPORT_SYMBOL_GPL(acpi_gpio_get_irq_resource);
198 
199 /**
200  * acpi_gpio_get_io_resource - Fetch details of an ACPI resource if it is a GPIO
201  *			       I/O resource or return False if not.
202  * @ares:	Pointer to the ACPI resource to fetch
203  * @agpio:	Pointer to a &struct acpi_resource_gpio to store the output pointer
204  */
205 bool acpi_gpio_get_io_resource(struct acpi_resource *ares,
206 			       struct acpi_resource_gpio **agpio)
207 {
208 	struct acpi_resource_gpio *gpio;
209 
210 	if (ares->type != ACPI_RESOURCE_TYPE_GPIO)
211 		return false;
212 
213 	gpio = &ares->data.gpio;
214 	if (gpio->connection_type != ACPI_RESOURCE_GPIO_TYPE_IO)
215 		return false;
216 
217 	*agpio = gpio;
218 	return true;
219 }
220 EXPORT_SYMBOL_GPL(acpi_gpio_get_io_resource);
221 
222 static void acpi_gpiochip_request_irq(struct acpi_gpio_chip *acpi_gpio,
223 				      struct acpi_gpio_event *event)
224 {
225 	int ret, value;
226 
227 	ret = request_threaded_irq(event->irq, NULL, event->handler,
228 				   event->irqflags | IRQF_ONESHOT, "ACPI:Event", event);
229 	if (ret) {
230 		dev_err(acpi_gpio->chip->parent,
231 			"Failed to setup interrupt handler for %d\n",
232 			event->irq);
233 		return;
234 	}
235 
236 	if (event->irq_is_wake)
237 		enable_irq_wake(event->irq);
238 
239 	event->irq_requested = true;
240 
241 	/* Make sure we trigger the initial state of edge-triggered IRQs */
242 	if (run_edge_events_on_boot &&
243 	    (event->irqflags & (IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING))) {
244 		value = gpiod_get_raw_value_cansleep(event->desc);
245 		if (((event->irqflags & IRQF_TRIGGER_RISING) && value == 1) ||
246 		    ((event->irqflags & IRQF_TRIGGER_FALLING) && value == 0))
247 			event->handler(event->irq, event);
248 	}
249 }
250 
251 static void acpi_gpiochip_request_irqs(struct acpi_gpio_chip *acpi_gpio)
252 {
253 	struct acpi_gpio_event *event;
254 
255 	list_for_each_entry(event, &acpi_gpio->events, node)
256 		acpi_gpiochip_request_irq(acpi_gpio, event);
257 }
258 
259 static enum gpiod_flags
260 acpi_gpio_to_gpiod_flags(const struct acpi_resource_gpio *agpio, int polarity)
261 {
262 	/* GpioInt() implies input configuration */
263 	if (agpio->connection_type == ACPI_RESOURCE_GPIO_TYPE_INT)
264 		return GPIOD_IN;
265 
266 	switch (agpio->io_restriction) {
267 	case ACPI_IO_RESTRICT_INPUT:
268 		return GPIOD_IN;
269 	case ACPI_IO_RESTRICT_OUTPUT:
270 		/*
271 		 * ACPI GPIO resources don't contain an initial value for the
272 		 * GPIO. Therefore we deduce that value from the pull field
273 		 * and the polarity instead. If the pin is pulled up we assume
274 		 * default to be high, if it is pulled down we assume default
275 		 * to be low, otherwise we leave pin untouched. For active low
276 		 * polarity values will be switched. See also
277 		 * Documentation/firmware-guide/acpi/gpio-properties.rst.
278 		 */
279 		switch (agpio->pin_config) {
280 		case ACPI_PIN_CONFIG_PULLUP:
281 			return polarity == GPIO_ACTIVE_LOW ? GPIOD_OUT_LOW : GPIOD_OUT_HIGH;
282 		case ACPI_PIN_CONFIG_PULLDOWN:
283 			return polarity == GPIO_ACTIVE_LOW ? GPIOD_OUT_HIGH : GPIOD_OUT_LOW;
284 		default:
285 			break;
286 		}
287 		break;
288 	default:
289 		break;
290 	}
291 
292 	/*
293 	 * Assume that the BIOS has configured the direction and pull
294 	 * accordingly.
295 	 */
296 	return GPIOD_ASIS;
297 }
298 
299 static struct gpio_desc *acpi_request_own_gpiod(struct gpio_chip *chip,
300 						struct acpi_resource_gpio *agpio,
301 						unsigned int index,
302 						const char *label)
303 {
304 	int polarity = GPIO_ACTIVE_HIGH;
305 	enum gpiod_flags flags = acpi_gpio_to_gpiod_flags(agpio, polarity);
306 	unsigned int pin = agpio->pin_table[index];
307 	struct gpio_desc *desc;
308 	int ret;
309 
310 	desc = gpiochip_request_own_desc(chip, pin, label, polarity, flags);
311 	if (IS_ERR(desc))
312 		return desc;
313 
314 	ret = gpio_set_debounce_timeout(desc, agpio->debounce_timeout);
315 	if (ret)
316 		dev_warn(chip->parent,
317 			 "Failed to set debounce-timeout for pin 0x%04X, err %d\n",
318 			 pin, ret);
319 
320 	return desc;
321 }
322 
323 static bool acpi_gpio_in_ignore_list(const char *controller_in, int pin_in)
324 {
325 	const char *controller, *pin_str;
326 	int len, pin;
327 	char *endp;
328 
329 	controller = ignore_wake;
330 	while (controller) {
331 		pin_str = strchr(controller, '@');
332 		if (!pin_str)
333 			goto err;
334 
335 		len = pin_str - controller;
336 		if (len == strlen(controller_in) &&
337 		    strncmp(controller, controller_in, len) == 0) {
338 			pin = simple_strtoul(pin_str + 1, &endp, 10);
339 			if (*endp != 0 && *endp != ',')
340 				goto err;
341 
342 			if (pin == pin_in)
343 				return true;
344 		}
345 
346 		controller = strchr(controller, ',');
347 		if (controller)
348 			controller++;
349 	}
350 
351 	return false;
352 err:
353 	pr_err_once("Error invalid value for gpiolib_acpi.ignore_wake: %s\n",
354 		    ignore_wake);
355 	return false;
356 }
357 
358 static bool acpi_gpio_irq_is_wake(struct device *parent,
359 				  struct acpi_resource_gpio *agpio)
360 {
361 	int pin = agpio->pin_table[0];
362 
363 	if (agpio->wake_capable != ACPI_WAKE_CAPABLE)
364 		return false;
365 
366 	if (acpi_gpio_in_ignore_list(dev_name(parent), pin)) {
367 		dev_info(parent, "Ignoring wakeup on pin %d\n", pin);
368 		return false;
369 	}
370 
371 	return true;
372 }
373 
374 /* Always returns AE_OK so that we keep looping over the resources */
375 static acpi_status acpi_gpiochip_alloc_event(struct acpi_resource *ares,
376 					     void *context)
377 {
378 	struct acpi_gpio_chip *acpi_gpio = context;
379 	struct gpio_chip *chip = acpi_gpio->chip;
380 	struct acpi_resource_gpio *agpio;
381 	acpi_handle handle, evt_handle;
382 	struct acpi_gpio_event *event;
383 	irq_handler_t handler = NULL;
384 	struct gpio_desc *desc;
385 	int ret, pin, irq;
386 
387 	if (!acpi_gpio_get_irq_resource(ares, &agpio))
388 		return AE_OK;
389 
390 	handle = ACPI_HANDLE(chip->parent);
391 	pin = agpio->pin_table[0];
392 
393 	if (pin <= 255) {
394 		char ev_name[5];
395 		sprintf(ev_name, "_%c%02hhX",
396 			agpio->triggering == ACPI_EDGE_SENSITIVE ? 'E' : 'L',
397 			pin);
398 		if (ACPI_SUCCESS(acpi_get_handle(handle, ev_name, &evt_handle)))
399 			handler = acpi_gpio_irq_handler;
400 	}
401 	if (!handler) {
402 		if (ACPI_SUCCESS(acpi_get_handle(handle, "_EVT", &evt_handle)))
403 			handler = acpi_gpio_irq_handler_evt;
404 	}
405 	if (!handler)
406 		return AE_OK;
407 
408 	desc = acpi_request_own_gpiod(chip, agpio, 0, "ACPI:Event");
409 	if (IS_ERR(desc)) {
410 		dev_err(chip->parent,
411 			"Failed to request GPIO for pin 0x%04X, err %ld\n",
412 			pin, PTR_ERR(desc));
413 		return AE_OK;
414 	}
415 
416 	ret = gpiochip_lock_as_irq(chip, pin);
417 	if (ret) {
418 		dev_err(chip->parent,
419 			"Failed to lock GPIO pin 0x%04X as interrupt, err %d\n",
420 			pin, ret);
421 		goto fail_free_desc;
422 	}
423 
424 	irq = gpiod_to_irq(desc);
425 	if (irq < 0) {
426 		dev_err(chip->parent,
427 			"Failed to translate GPIO pin 0x%04X to IRQ, err %d\n",
428 			pin, irq);
429 		goto fail_unlock_irq;
430 	}
431 
432 	event = kzalloc(sizeof(*event), GFP_KERNEL);
433 	if (!event)
434 		goto fail_unlock_irq;
435 
436 	event->irqflags = IRQF_ONESHOT;
437 	if (agpio->triggering == ACPI_LEVEL_SENSITIVE) {
438 		if (agpio->polarity == ACPI_ACTIVE_HIGH)
439 			event->irqflags |= IRQF_TRIGGER_HIGH;
440 		else
441 			event->irqflags |= IRQF_TRIGGER_LOW;
442 	} else {
443 		switch (agpio->polarity) {
444 		case ACPI_ACTIVE_HIGH:
445 			event->irqflags |= IRQF_TRIGGER_RISING;
446 			break;
447 		case ACPI_ACTIVE_LOW:
448 			event->irqflags |= IRQF_TRIGGER_FALLING;
449 			break;
450 		default:
451 			event->irqflags |= IRQF_TRIGGER_RISING |
452 					   IRQF_TRIGGER_FALLING;
453 			break;
454 		}
455 	}
456 
457 	event->handle = evt_handle;
458 	event->handler = handler;
459 	event->irq = irq;
460 	event->irq_is_wake = acpi_gpio_irq_is_wake(chip->parent, agpio);
461 	event->pin = pin;
462 	event->desc = desc;
463 
464 	list_add_tail(&event->node, &acpi_gpio->events);
465 
466 	return AE_OK;
467 
468 fail_unlock_irq:
469 	gpiochip_unlock_as_irq(chip, pin);
470 fail_free_desc:
471 	gpiochip_free_own_desc(desc);
472 
473 	return AE_OK;
474 }
475 
476 /**
477  * acpi_gpiochip_request_interrupts() - Register isr for gpio chip ACPI events
478  * @chip:      GPIO chip
479  *
480  * ACPI5 platforms can use GPIO signaled ACPI events. These GPIO interrupts are
481  * handled by ACPI event methods which need to be called from the GPIO
482  * chip's interrupt handler. acpi_gpiochip_request_interrupts() finds out which
483  * GPIO pins have ACPI event methods and assigns interrupt handlers that calls
484  * the ACPI event methods for those pins.
485  */
486 void acpi_gpiochip_request_interrupts(struct gpio_chip *chip)
487 {
488 	struct acpi_gpio_chip *acpi_gpio;
489 	acpi_handle handle;
490 	acpi_status status;
491 	bool defer;
492 
493 	if (!chip->parent || !chip->to_irq)
494 		return;
495 
496 	handle = ACPI_HANDLE(chip->parent);
497 	if (!handle)
498 		return;
499 
500 	status = acpi_get_data(handle, acpi_gpio_chip_dh, (void **)&acpi_gpio);
501 	if (ACPI_FAILURE(status))
502 		return;
503 
504 	acpi_walk_resources(handle, "_AEI",
505 			    acpi_gpiochip_alloc_event, acpi_gpio);
506 
507 	mutex_lock(&acpi_gpio_deferred_req_irqs_lock);
508 	defer = !acpi_gpio_deferred_req_irqs_done;
509 	if (defer)
510 		list_add(&acpi_gpio->deferred_req_irqs_list_entry,
511 			 &acpi_gpio_deferred_req_irqs_list);
512 	mutex_unlock(&acpi_gpio_deferred_req_irqs_lock);
513 
514 	if (defer)
515 		return;
516 
517 	acpi_gpiochip_request_irqs(acpi_gpio);
518 }
519 EXPORT_SYMBOL_GPL(acpi_gpiochip_request_interrupts);
520 
521 /**
522  * acpi_gpiochip_free_interrupts() - Free GPIO ACPI event interrupts.
523  * @chip:      GPIO chip
524  *
525  * Free interrupts associated with GPIO ACPI event method for the given
526  * GPIO chip.
527  */
528 void acpi_gpiochip_free_interrupts(struct gpio_chip *chip)
529 {
530 	struct acpi_gpio_chip *acpi_gpio;
531 	struct acpi_gpio_event *event, *ep;
532 	acpi_handle handle;
533 	acpi_status status;
534 
535 	if (!chip->parent || !chip->to_irq)
536 		return;
537 
538 	handle = ACPI_HANDLE(chip->parent);
539 	if (!handle)
540 		return;
541 
542 	status = acpi_get_data(handle, acpi_gpio_chip_dh, (void **)&acpi_gpio);
543 	if (ACPI_FAILURE(status))
544 		return;
545 
546 	mutex_lock(&acpi_gpio_deferred_req_irqs_lock);
547 	if (!list_empty(&acpi_gpio->deferred_req_irqs_list_entry))
548 		list_del_init(&acpi_gpio->deferred_req_irqs_list_entry);
549 	mutex_unlock(&acpi_gpio_deferred_req_irqs_lock);
550 
551 	list_for_each_entry_safe_reverse(event, ep, &acpi_gpio->events, node) {
552 		if (event->irq_requested) {
553 			if (event->irq_is_wake)
554 				disable_irq_wake(event->irq);
555 
556 			free_irq(event->irq, event);
557 		}
558 
559 		gpiochip_unlock_as_irq(chip, event->pin);
560 		gpiochip_free_own_desc(event->desc);
561 		list_del(&event->node);
562 		kfree(event);
563 	}
564 }
565 EXPORT_SYMBOL_GPL(acpi_gpiochip_free_interrupts);
566 
567 int acpi_dev_add_driver_gpios(struct acpi_device *adev,
568 			      const struct acpi_gpio_mapping *gpios)
569 {
570 	if (adev && gpios) {
571 		adev->driver_gpios = gpios;
572 		return 0;
573 	}
574 	return -EINVAL;
575 }
576 EXPORT_SYMBOL_GPL(acpi_dev_add_driver_gpios);
577 
578 void acpi_dev_remove_driver_gpios(struct acpi_device *adev)
579 {
580 	if (adev)
581 		adev->driver_gpios = NULL;
582 }
583 EXPORT_SYMBOL_GPL(acpi_dev_remove_driver_gpios);
584 
585 static void devm_acpi_dev_release_driver_gpios(struct device *dev, void *res)
586 {
587 	acpi_dev_remove_driver_gpios(ACPI_COMPANION(dev));
588 }
589 
590 int devm_acpi_dev_add_driver_gpios(struct device *dev,
591 				   const struct acpi_gpio_mapping *gpios)
592 {
593 	void *res;
594 	int ret;
595 
596 	res = devres_alloc(devm_acpi_dev_release_driver_gpios, 0, GFP_KERNEL);
597 	if (!res)
598 		return -ENOMEM;
599 
600 	ret = acpi_dev_add_driver_gpios(ACPI_COMPANION(dev), gpios);
601 	if (ret) {
602 		devres_free(res);
603 		return ret;
604 	}
605 	devres_add(dev, res);
606 	return 0;
607 }
608 EXPORT_SYMBOL_GPL(devm_acpi_dev_add_driver_gpios);
609 
610 void devm_acpi_dev_remove_driver_gpios(struct device *dev)
611 {
612 	WARN_ON(devres_release(dev, devm_acpi_dev_release_driver_gpios, NULL, NULL));
613 }
614 EXPORT_SYMBOL_GPL(devm_acpi_dev_remove_driver_gpios);
615 
616 static bool acpi_get_driver_gpio_data(struct acpi_device *adev,
617 				      const char *name, int index,
618 				      struct fwnode_reference_args *args,
619 				      unsigned int *quirks)
620 {
621 	const struct acpi_gpio_mapping *gm;
622 
623 	if (!adev->driver_gpios)
624 		return false;
625 
626 	for (gm = adev->driver_gpios; gm->name; gm++)
627 		if (!strcmp(name, gm->name) && gm->data && index < gm->size) {
628 			const struct acpi_gpio_params *par = gm->data + index;
629 
630 			args->fwnode = acpi_fwnode_handle(adev);
631 			args->args[0] = par->crs_entry_index;
632 			args->args[1] = par->line_index;
633 			args->args[2] = par->active_low;
634 			args->nargs = 3;
635 
636 			*quirks = gm->quirks;
637 			return true;
638 		}
639 
640 	return false;
641 }
642 
643 static int
644 __acpi_gpio_update_gpiod_flags(enum gpiod_flags *flags, enum gpiod_flags update)
645 {
646 	const enum gpiod_flags mask =
647 		GPIOD_FLAGS_BIT_DIR_SET | GPIOD_FLAGS_BIT_DIR_OUT |
648 		GPIOD_FLAGS_BIT_DIR_VAL;
649 	int ret = 0;
650 
651 	/*
652 	 * Check if the BIOS has IoRestriction with explicitly set direction
653 	 * and update @flags accordingly. Otherwise use whatever caller asked
654 	 * for.
655 	 */
656 	if (update & GPIOD_FLAGS_BIT_DIR_SET) {
657 		enum gpiod_flags diff = *flags ^ update;
658 
659 		/*
660 		 * Check if caller supplied incompatible GPIO initialization
661 		 * flags.
662 		 *
663 		 * Return %-EINVAL to notify that firmware has different
664 		 * settings and we are going to use them.
665 		 */
666 		if (((*flags & GPIOD_FLAGS_BIT_DIR_SET) && (diff & GPIOD_FLAGS_BIT_DIR_OUT)) ||
667 		    ((*flags & GPIOD_FLAGS_BIT_DIR_OUT) && (diff & GPIOD_FLAGS_BIT_DIR_VAL)))
668 			ret = -EINVAL;
669 		*flags = (*flags & ~mask) | (update & mask);
670 	}
671 	return ret;
672 }
673 
674 int
675 acpi_gpio_update_gpiod_flags(enum gpiod_flags *flags, struct acpi_gpio_info *info)
676 {
677 	struct device *dev = &info->adev->dev;
678 	enum gpiod_flags old = *flags;
679 	int ret;
680 
681 	ret = __acpi_gpio_update_gpiod_flags(&old, info->flags);
682 	if (info->quirks & ACPI_GPIO_QUIRK_NO_IO_RESTRICTION) {
683 		if (ret)
684 			dev_warn(dev, FW_BUG "GPIO not in correct mode, fixing\n");
685 	} else {
686 		if (ret)
687 			dev_dbg(dev, "Override GPIO initialization flags\n");
688 		*flags = old;
689 	}
690 
691 	return ret;
692 }
693 
694 int acpi_gpio_update_gpiod_lookup_flags(unsigned long *lookupflags,
695 					struct acpi_gpio_info *info)
696 {
697 	switch (info->pin_config) {
698 	case ACPI_PIN_CONFIG_PULLUP:
699 		*lookupflags |= GPIO_PULL_UP;
700 		break;
701 	case ACPI_PIN_CONFIG_PULLDOWN:
702 		*lookupflags |= GPIO_PULL_DOWN;
703 		break;
704 	default:
705 		break;
706 	}
707 
708 	if (info->polarity == GPIO_ACTIVE_LOW)
709 		*lookupflags |= GPIO_ACTIVE_LOW;
710 
711 	return 0;
712 }
713 
714 struct acpi_gpio_lookup {
715 	struct acpi_gpio_info info;
716 	int index;
717 	u16 pin_index;
718 	bool active_low;
719 	struct gpio_desc *desc;
720 	int n;
721 };
722 
723 static int acpi_populate_gpio_lookup(struct acpi_resource *ares, void *data)
724 {
725 	struct acpi_gpio_lookup *lookup = data;
726 
727 	if (ares->type != ACPI_RESOURCE_TYPE_GPIO)
728 		return 1;
729 
730 	if (!lookup->desc) {
731 		const struct acpi_resource_gpio *agpio = &ares->data.gpio;
732 		bool gpioint = agpio->connection_type == ACPI_RESOURCE_GPIO_TYPE_INT;
733 		struct gpio_desc *desc;
734 		u16 pin_index;
735 
736 		if (lookup->info.quirks & ACPI_GPIO_QUIRK_ONLY_GPIOIO && gpioint)
737 			lookup->index++;
738 
739 		if (lookup->n++ != lookup->index)
740 			return 1;
741 
742 		pin_index = lookup->pin_index;
743 		if (pin_index >= agpio->pin_table_length)
744 			return 1;
745 
746 		if (lookup->info.quirks & ACPI_GPIO_QUIRK_ABSOLUTE_NUMBER)
747 			desc = gpio_to_desc(agpio->pin_table[pin_index]);
748 		else
749 			desc = acpi_get_gpiod(agpio->resource_source.string_ptr,
750 					      agpio->pin_table[pin_index]);
751 		lookup->desc = desc;
752 		lookup->info.pin_config = agpio->pin_config;
753 		lookup->info.debounce = agpio->debounce_timeout;
754 		lookup->info.gpioint = gpioint;
755 
756 		/*
757 		 * Polarity and triggering are only specified for GpioInt
758 		 * resource.
759 		 * Note: we expect here:
760 		 * - ACPI_ACTIVE_LOW == GPIO_ACTIVE_LOW
761 		 * - ACPI_ACTIVE_HIGH == GPIO_ACTIVE_HIGH
762 		 */
763 		if (lookup->info.gpioint) {
764 			lookup->info.polarity = agpio->polarity;
765 			lookup->info.triggering = agpio->triggering;
766 		} else {
767 			lookup->info.polarity = lookup->active_low;
768 		}
769 
770 		lookup->info.flags = acpi_gpio_to_gpiod_flags(agpio, lookup->info.polarity);
771 	}
772 
773 	return 1;
774 }
775 
776 static int acpi_gpio_resource_lookup(struct acpi_gpio_lookup *lookup,
777 				     struct acpi_gpio_info *info)
778 {
779 	struct acpi_device *adev = lookup->info.adev;
780 	struct list_head res_list;
781 	int ret;
782 
783 	INIT_LIST_HEAD(&res_list);
784 
785 	ret = acpi_dev_get_resources(adev, &res_list,
786 				     acpi_populate_gpio_lookup,
787 				     lookup);
788 	if (ret < 0)
789 		return ret;
790 
791 	acpi_dev_free_resource_list(&res_list);
792 
793 	if (!lookup->desc)
794 		return -ENOENT;
795 
796 	if (info)
797 		*info = lookup->info;
798 	return 0;
799 }
800 
801 static int acpi_gpio_property_lookup(struct fwnode_handle *fwnode,
802 				     const char *propname, int index,
803 				     struct acpi_gpio_lookup *lookup)
804 {
805 	struct fwnode_reference_args args;
806 	unsigned int quirks = 0;
807 	int ret;
808 
809 	memset(&args, 0, sizeof(args));
810 	ret = __acpi_node_get_property_reference(fwnode, propname, index, 3,
811 						 &args);
812 	if (ret) {
813 		struct acpi_device *adev = to_acpi_device_node(fwnode);
814 
815 		if (!adev)
816 			return ret;
817 
818 		if (!acpi_get_driver_gpio_data(adev, propname, index, &args,
819 					       &quirks))
820 			return ret;
821 	}
822 	/*
823 	 * The property was found and resolved, so need to lookup the GPIO based
824 	 * on returned args.
825 	 */
826 	if (!to_acpi_device_node(args.fwnode))
827 		return -EINVAL;
828 	if (args.nargs != 3)
829 		return -EPROTO;
830 
831 	lookup->index = args.args[0];
832 	lookup->pin_index = args.args[1];
833 	lookup->active_low = !!args.args[2];
834 
835 	lookup->info.adev = to_acpi_device_node(args.fwnode);
836 	lookup->info.quirks = quirks;
837 
838 	return 0;
839 }
840 
841 /**
842  * acpi_get_gpiod_by_index() - get a GPIO descriptor from device resources
843  * @adev: pointer to a ACPI device to get GPIO from
844  * @propname: Property name of the GPIO (optional)
845  * @index: index of GpioIo/GpioInt resource (starting from %0)
846  * @info: info pointer to fill in (optional)
847  *
848  * Function goes through ACPI resources for @adev and based on @index looks
849  * up a GpioIo/GpioInt resource, translates it to the Linux GPIO descriptor,
850  * and returns it. @index matches GpioIo/GpioInt resources only so if there
851  * are total %3 GPIO resources, the index goes from %0 to %2.
852  *
853  * If @propname is specified the GPIO is looked using device property. In
854  * that case @index is used to select the GPIO entry in the property value
855  * (in case of multiple).
856  *
857  * If the GPIO cannot be translated or there is an error, an ERR_PTR is
858  * returned.
859  *
860  * Note: if the GPIO resource has multiple entries in the pin list, this
861  * function only returns the first.
862  */
863 static struct gpio_desc *acpi_get_gpiod_by_index(struct acpi_device *adev,
864 					  const char *propname, int index,
865 					  struct acpi_gpio_info *info)
866 {
867 	struct acpi_gpio_lookup lookup;
868 	int ret;
869 
870 	if (!adev)
871 		return ERR_PTR(-ENODEV);
872 
873 	memset(&lookup, 0, sizeof(lookup));
874 	lookup.index = index;
875 
876 	if (propname) {
877 		dev_dbg(&adev->dev, "GPIO: looking up %s\n", propname);
878 
879 		ret = acpi_gpio_property_lookup(acpi_fwnode_handle(adev),
880 						propname, index, &lookup);
881 		if (ret)
882 			return ERR_PTR(ret);
883 
884 		dev_dbg(&adev->dev, "GPIO: _DSD returned %s %d %u %u\n",
885 			dev_name(&lookup.info.adev->dev), lookup.index,
886 			lookup.pin_index, lookup.active_low);
887 	} else {
888 		dev_dbg(&adev->dev, "GPIO: looking up %d in _CRS\n", index);
889 		lookup.info.adev = adev;
890 	}
891 
892 	ret = acpi_gpio_resource_lookup(&lookup, info);
893 	return ret ? ERR_PTR(ret) : lookup.desc;
894 }
895 
896 static bool acpi_can_fallback_to_crs(struct acpi_device *adev,
897 				     const char *con_id)
898 {
899 	/* Never allow fallback if the device has properties */
900 	if (acpi_dev_has_props(adev) || adev->driver_gpios)
901 		return false;
902 
903 	return con_id == NULL;
904 }
905 
906 struct gpio_desc *acpi_find_gpio(struct device *dev,
907 				 const char *con_id,
908 				 unsigned int idx,
909 				 enum gpiod_flags *dflags,
910 				 unsigned long *lookupflags)
911 {
912 	struct acpi_device *adev = ACPI_COMPANION(dev);
913 	struct acpi_gpio_info info;
914 	struct gpio_desc *desc;
915 	char propname[32];
916 	int i;
917 
918 	/* Try first from _DSD */
919 	for (i = 0; i < ARRAY_SIZE(gpio_suffixes); i++) {
920 		if (con_id) {
921 			snprintf(propname, sizeof(propname), "%s-%s",
922 				 con_id, gpio_suffixes[i]);
923 		} else {
924 			snprintf(propname, sizeof(propname), "%s",
925 				 gpio_suffixes[i]);
926 		}
927 
928 		desc = acpi_get_gpiod_by_index(adev, propname, idx, &info);
929 		if (!IS_ERR(desc))
930 			break;
931 		if (PTR_ERR(desc) == -EPROBE_DEFER)
932 			return ERR_CAST(desc);
933 	}
934 
935 	/* Then from plain _CRS GPIOs */
936 	if (IS_ERR(desc)) {
937 		if (!acpi_can_fallback_to_crs(adev, con_id))
938 			return ERR_PTR(-ENOENT);
939 
940 		desc = acpi_get_gpiod_by_index(adev, NULL, idx, &info);
941 		if (IS_ERR(desc))
942 			return desc;
943 	}
944 
945 	if (info.gpioint &&
946 	    (*dflags == GPIOD_OUT_LOW || *dflags == GPIOD_OUT_HIGH)) {
947 		dev_dbg(dev, "refusing GpioInt() entry when doing GPIOD_OUT_* lookup\n");
948 		return ERR_PTR(-ENOENT);
949 	}
950 
951 	acpi_gpio_update_gpiod_flags(dflags, &info);
952 	acpi_gpio_update_gpiod_lookup_flags(lookupflags, &info);
953 	return desc;
954 }
955 
956 /**
957  * acpi_node_get_gpiod() - get a GPIO descriptor from ACPI resources
958  * @fwnode: pointer to an ACPI firmware node to get the GPIO information from
959  * @propname: Property name of the GPIO
960  * @index: index of GpioIo/GpioInt resource (starting from %0)
961  * @info: info pointer to fill in (optional)
962  *
963  * If @fwnode is an ACPI device object, call acpi_get_gpiod_by_index() for it.
964  * Otherwise (i.e. it is a data-only non-device object), use the property-based
965  * GPIO lookup to get to the GPIO resource with the relevant information and use
966  * that to obtain the GPIO descriptor to return.
967  *
968  * If the GPIO cannot be translated or there is an error an ERR_PTR is
969  * returned.
970  */
971 struct gpio_desc *acpi_node_get_gpiod(struct fwnode_handle *fwnode,
972 				      const char *propname, int index,
973 				      struct acpi_gpio_info *info)
974 {
975 	struct acpi_gpio_lookup lookup;
976 	struct acpi_device *adev;
977 	int ret;
978 
979 	adev = to_acpi_device_node(fwnode);
980 	if (adev)
981 		return acpi_get_gpiod_by_index(adev, propname, index, info);
982 
983 	if (!is_acpi_data_node(fwnode))
984 		return ERR_PTR(-ENODEV);
985 
986 	if (!propname)
987 		return ERR_PTR(-EINVAL);
988 
989 	memset(&lookup, 0, sizeof(lookup));
990 	lookup.index = index;
991 
992 	ret = acpi_gpio_property_lookup(fwnode, propname, index, &lookup);
993 	if (ret)
994 		return ERR_PTR(ret);
995 
996 	ret = acpi_gpio_resource_lookup(&lookup, info);
997 	return ret ? ERR_PTR(ret) : lookup.desc;
998 }
999 
1000 /**
1001  * acpi_dev_gpio_irq_get_by() - Find GpioInt and translate it to Linux IRQ number
1002  * @adev: pointer to a ACPI device to get IRQ from
1003  * @name: optional name of GpioInt resource
1004  * @index: index of GpioInt resource (starting from %0)
1005  *
1006  * If the device has one or more GpioInt resources, this function can be
1007  * used to translate from the GPIO offset in the resource to the Linux IRQ
1008  * number.
1009  *
1010  * The function is idempotent, though each time it runs it will configure GPIO
1011  * pin direction according to the flags in GpioInt resource.
1012  *
1013  * The function takes optional @name parameter. If the resource has a property
1014  * name, then only those will be taken into account.
1015  *
1016  * Return: Linux IRQ number (> %0) on success, negative errno on failure.
1017  */
1018 int acpi_dev_gpio_irq_get_by(struct acpi_device *adev, const char *name, int index)
1019 {
1020 	int idx, i;
1021 	unsigned int irq_flags;
1022 	int ret;
1023 
1024 	for (i = 0, idx = 0; idx <= index; i++) {
1025 		struct acpi_gpio_info info;
1026 		struct gpio_desc *desc;
1027 
1028 		desc = acpi_get_gpiod_by_index(adev, name, i, &info);
1029 
1030 		/* Ignore -EPROBE_DEFER, it only matters if idx matches */
1031 		if (IS_ERR(desc) && PTR_ERR(desc) != -EPROBE_DEFER)
1032 			return PTR_ERR(desc);
1033 
1034 		if (info.gpioint && idx++ == index) {
1035 			unsigned long lflags = GPIO_LOOKUP_FLAGS_DEFAULT;
1036 			enum gpiod_flags dflags = GPIOD_ASIS;
1037 			char label[32];
1038 			int irq;
1039 
1040 			if (IS_ERR(desc))
1041 				return PTR_ERR(desc);
1042 
1043 			irq = gpiod_to_irq(desc);
1044 			if (irq < 0)
1045 				return irq;
1046 
1047 			acpi_gpio_update_gpiod_flags(&dflags, &info);
1048 			acpi_gpio_update_gpiod_lookup_flags(&lflags, &info);
1049 
1050 			snprintf(label, sizeof(label), "GpioInt() %d", index);
1051 			ret = gpiod_configure_flags(desc, label, lflags, dflags);
1052 			if (ret < 0)
1053 				return ret;
1054 
1055 			ret = gpio_set_debounce_timeout(desc, info.debounce);
1056 			if (ret)
1057 				return ret;
1058 
1059 			irq_flags = acpi_dev_get_irq_type(info.triggering,
1060 							  info.polarity);
1061 
1062 			/* Set type if specified and different than the current one */
1063 			if (irq_flags != IRQ_TYPE_NONE &&
1064 			    irq_flags != irq_get_trigger_type(irq))
1065 				irq_set_irq_type(irq, irq_flags);
1066 
1067 			return irq;
1068 		}
1069 
1070 	}
1071 	return -ENOENT;
1072 }
1073 EXPORT_SYMBOL_GPL(acpi_dev_gpio_irq_get_by);
1074 
1075 static acpi_status
1076 acpi_gpio_adr_space_handler(u32 function, acpi_physical_address address,
1077 			    u32 bits, u64 *value, void *handler_context,
1078 			    void *region_context)
1079 {
1080 	struct acpi_gpio_chip *achip = region_context;
1081 	struct gpio_chip *chip = achip->chip;
1082 	struct acpi_resource_gpio *agpio;
1083 	struct acpi_resource *ares;
1084 	u16 pin_index = address;
1085 	acpi_status status;
1086 	int length;
1087 	int i;
1088 
1089 	status = acpi_buffer_to_resource(achip->conn_info.connection,
1090 					 achip->conn_info.length, &ares);
1091 	if (ACPI_FAILURE(status))
1092 		return status;
1093 
1094 	if (WARN_ON(ares->type != ACPI_RESOURCE_TYPE_GPIO)) {
1095 		ACPI_FREE(ares);
1096 		return AE_BAD_PARAMETER;
1097 	}
1098 
1099 	agpio = &ares->data.gpio;
1100 
1101 	if (WARN_ON(agpio->io_restriction == ACPI_IO_RESTRICT_INPUT &&
1102 	    function == ACPI_WRITE)) {
1103 		ACPI_FREE(ares);
1104 		return AE_BAD_PARAMETER;
1105 	}
1106 
1107 	length = min_t(u16, agpio->pin_table_length, pin_index + bits);
1108 	for (i = pin_index; i < length; ++i) {
1109 		int pin = agpio->pin_table[i];
1110 		struct acpi_gpio_connection *conn;
1111 		struct gpio_desc *desc;
1112 		bool found;
1113 
1114 		mutex_lock(&achip->conn_lock);
1115 
1116 		found = false;
1117 		list_for_each_entry(conn, &achip->conns, node) {
1118 			if (conn->pin == pin) {
1119 				found = true;
1120 				desc = conn->desc;
1121 				break;
1122 			}
1123 		}
1124 
1125 		/*
1126 		 * The same GPIO can be shared between operation region and
1127 		 * event but only if the access here is ACPI_READ. In that
1128 		 * case we "borrow" the event GPIO instead.
1129 		 */
1130 		if (!found && agpio->shareable == ACPI_SHARED &&
1131 		     function == ACPI_READ) {
1132 			struct acpi_gpio_event *event;
1133 
1134 			list_for_each_entry(event, &achip->events, node) {
1135 				if (event->pin == pin) {
1136 					desc = event->desc;
1137 					found = true;
1138 					break;
1139 				}
1140 			}
1141 		}
1142 
1143 		if (!found) {
1144 			desc = acpi_request_own_gpiod(chip, agpio, i, "ACPI:OpRegion");
1145 			if (IS_ERR(desc)) {
1146 				mutex_unlock(&achip->conn_lock);
1147 				status = AE_ERROR;
1148 				goto out;
1149 			}
1150 
1151 			conn = kzalloc(sizeof(*conn), GFP_KERNEL);
1152 			if (!conn) {
1153 				gpiochip_free_own_desc(desc);
1154 				mutex_unlock(&achip->conn_lock);
1155 				status = AE_NO_MEMORY;
1156 				goto out;
1157 			}
1158 
1159 			conn->pin = pin;
1160 			conn->desc = desc;
1161 			list_add_tail(&conn->node, &achip->conns);
1162 		}
1163 
1164 		mutex_unlock(&achip->conn_lock);
1165 
1166 		if (function == ACPI_WRITE)
1167 			gpiod_set_raw_value_cansleep(desc, !!(*value & BIT(i)));
1168 		else
1169 			*value |= (u64)gpiod_get_raw_value_cansleep(desc) << i;
1170 	}
1171 
1172 out:
1173 	ACPI_FREE(ares);
1174 	return status;
1175 }
1176 
1177 static void acpi_gpiochip_request_regions(struct acpi_gpio_chip *achip)
1178 {
1179 	struct gpio_chip *chip = achip->chip;
1180 	acpi_handle handle = ACPI_HANDLE(chip->parent);
1181 	acpi_status status;
1182 
1183 	INIT_LIST_HEAD(&achip->conns);
1184 	mutex_init(&achip->conn_lock);
1185 	status = acpi_install_address_space_handler(handle, ACPI_ADR_SPACE_GPIO,
1186 						    acpi_gpio_adr_space_handler,
1187 						    NULL, achip);
1188 	if (ACPI_FAILURE(status))
1189 		dev_err(chip->parent,
1190 		        "Failed to install GPIO OpRegion handler\n");
1191 }
1192 
1193 static void acpi_gpiochip_free_regions(struct acpi_gpio_chip *achip)
1194 {
1195 	struct gpio_chip *chip = achip->chip;
1196 	acpi_handle handle = ACPI_HANDLE(chip->parent);
1197 	struct acpi_gpio_connection *conn, *tmp;
1198 	acpi_status status;
1199 
1200 	status = acpi_remove_address_space_handler(handle, ACPI_ADR_SPACE_GPIO,
1201 						   acpi_gpio_adr_space_handler);
1202 	if (ACPI_FAILURE(status)) {
1203 		dev_err(chip->parent,
1204 			"Failed to remove GPIO OpRegion handler\n");
1205 		return;
1206 	}
1207 
1208 	list_for_each_entry_safe_reverse(conn, tmp, &achip->conns, node) {
1209 		gpiochip_free_own_desc(conn->desc);
1210 		list_del(&conn->node);
1211 		kfree(conn);
1212 	}
1213 }
1214 
1215 static struct gpio_desc *
1216 acpi_gpiochip_parse_own_gpio(struct acpi_gpio_chip *achip,
1217 			     struct fwnode_handle *fwnode,
1218 			     const char **name,
1219 			     unsigned long *lflags,
1220 			     enum gpiod_flags *dflags)
1221 {
1222 	struct gpio_chip *chip = achip->chip;
1223 	struct gpio_desc *desc;
1224 	u32 gpios[2];
1225 	int ret;
1226 
1227 	*lflags = GPIO_LOOKUP_FLAGS_DEFAULT;
1228 	*dflags = GPIOD_ASIS;
1229 	*name = NULL;
1230 
1231 	ret = fwnode_property_read_u32_array(fwnode, "gpios", gpios,
1232 					     ARRAY_SIZE(gpios));
1233 	if (ret < 0)
1234 		return ERR_PTR(ret);
1235 
1236 	desc = gpiochip_get_desc(chip, gpios[0]);
1237 	if (IS_ERR(desc))
1238 		return desc;
1239 
1240 	if (gpios[1])
1241 		*lflags |= GPIO_ACTIVE_LOW;
1242 
1243 	if (fwnode_property_present(fwnode, "input"))
1244 		*dflags |= GPIOD_IN;
1245 	else if (fwnode_property_present(fwnode, "output-low"))
1246 		*dflags |= GPIOD_OUT_LOW;
1247 	else if (fwnode_property_present(fwnode, "output-high"))
1248 		*dflags |= GPIOD_OUT_HIGH;
1249 	else
1250 		return ERR_PTR(-EINVAL);
1251 
1252 	fwnode_property_read_string(fwnode, "line-name", name);
1253 
1254 	return desc;
1255 }
1256 
1257 static void acpi_gpiochip_scan_gpios(struct acpi_gpio_chip *achip)
1258 {
1259 	struct gpio_chip *chip = achip->chip;
1260 	struct fwnode_handle *fwnode;
1261 
1262 	device_for_each_child_node(chip->parent, fwnode) {
1263 		unsigned long lflags;
1264 		enum gpiod_flags dflags;
1265 		struct gpio_desc *desc;
1266 		const char *name;
1267 		int ret;
1268 
1269 		if (!fwnode_property_present(fwnode, "gpio-hog"))
1270 			continue;
1271 
1272 		desc = acpi_gpiochip_parse_own_gpio(achip, fwnode, &name,
1273 						    &lflags, &dflags);
1274 		if (IS_ERR(desc))
1275 			continue;
1276 
1277 		ret = gpiod_hog(desc, name, lflags, dflags);
1278 		if (ret) {
1279 			dev_err(chip->parent, "Failed to hog GPIO\n");
1280 			fwnode_handle_put(fwnode);
1281 			return;
1282 		}
1283 	}
1284 }
1285 
1286 void acpi_gpiochip_add(struct gpio_chip *chip)
1287 {
1288 	struct acpi_gpio_chip *acpi_gpio;
1289 	struct acpi_device *adev;
1290 	acpi_status status;
1291 
1292 	if (!chip || !chip->parent)
1293 		return;
1294 
1295 	adev = ACPI_COMPANION(chip->parent);
1296 	if (!adev)
1297 		return;
1298 
1299 	acpi_gpio = kzalloc(sizeof(*acpi_gpio), GFP_KERNEL);
1300 	if (!acpi_gpio) {
1301 		dev_err(chip->parent,
1302 			"Failed to allocate memory for ACPI GPIO chip\n");
1303 		return;
1304 	}
1305 
1306 	acpi_gpio->chip = chip;
1307 	INIT_LIST_HEAD(&acpi_gpio->events);
1308 	INIT_LIST_HEAD(&acpi_gpio->deferred_req_irqs_list_entry);
1309 
1310 	status = acpi_attach_data(adev->handle, acpi_gpio_chip_dh, acpi_gpio);
1311 	if (ACPI_FAILURE(status)) {
1312 		dev_err(chip->parent, "Failed to attach ACPI GPIO chip\n");
1313 		kfree(acpi_gpio);
1314 		return;
1315 	}
1316 
1317 	acpi_gpiochip_request_regions(acpi_gpio);
1318 	acpi_gpiochip_scan_gpios(acpi_gpio);
1319 	acpi_dev_clear_dependencies(adev);
1320 }
1321 
1322 void acpi_gpiochip_remove(struct gpio_chip *chip)
1323 {
1324 	struct acpi_gpio_chip *acpi_gpio;
1325 	acpi_handle handle;
1326 	acpi_status status;
1327 
1328 	if (!chip || !chip->parent)
1329 		return;
1330 
1331 	handle = ACPI_HANDLE(chip->parent);
1332 	if (!handle)
1333 		return;
1334 
1335 	status = acpi_get_data(handle, acpi_gpio_chip_dh, (void **)&acpi_gpio);
1336 	if (ACPI_FAILURE(status)) {
1337 		dev_warn(chip->parent, "Failed to retrieve ACPI GPIO chip\n");
1338 		return;
1339 	}
1340 
1341 	acpi_gpiochip_free_regions(acpi_gpio);
1342 
1343 	acpi_detach_data(handle, acpi_gpio_chip_dh);
1344 	kfree(acpi_gpio);
1345 }
1346 
1347 void acpi_gpio_dev_init(struct gpio_chip *gc, struct gpio_device *gdev)
1348 {
1349 	/* Set default fwnode to parent's one if present */
1350 	if (gc->parent)
1351 		ACPI_COMPANION_SET(&gdev->dev, ACPI_COMPANION(gc->parent));
1352 }
1353 
1354 static int acpi_gpio_package_count(const union acpi_object *obj)
1355 {
1356 	const union acpi_object *element = obj->package.elements;
1357 	const union acpi_object *end = element + obj->package.count;
1358 	unsigned int count = 0;
1359 
1360 	while (element < end) {
1361 		switch (element->type) {
1362 		case ACPI_TYPE_LOCAL_REFERENCE:
1363 			element += 3;
1364 			fallthrough;
1365 		case ACPI_TYPE_INTEGER:
1366 			element++;
1367 			count++;
1368 			break;
1369 
1370 		default:
1371 			return -EPROTO;
1372 		}
1373 	}
1374 
1375 	return count;
1376 }
1377 
1378 static int acpi_find_gpio_count(struct acpi_resource *ares, void *data)
1379 {
1380 	unsigned int *count = data;
1381 
1382 	if (ares->type == ACPI_RESOURCE_TYPE_GPIO)
1383 		*count += ares->data.gpio.pin_table_length;
1384 
1385 	return 1;
1386 }
1387 
1388 /**
1389  * acpi_gpio_count - count the GPIOs associated with a device / function
1390  * @dev:	GPIO consumer, can be %NULL for system-global GPIOs
1391  * @con_id:	function within the GPIO consumer
1392  *
1393  * Return:
1394  * The number of GPIOs associated with a device / function or %-ENOENT,
1395  * if no GPIO has been assigned to the requested function.
1396  */
1397 int acpi_gpio_count(struct device *dev, const char *con_id)
1398 {
1399 	struct acpi_device *adev = ACPI_COMPANION(dev);
1400 	const union acpi_object *obj;
1401 	const struct acpi_gpio_mapping *gm;
1402 	int count = -ENOENT;
1403 	int ret;
1404 	char propname[32];
1405 	unsigned int i;
1406 
1407 	/* Try first from _DSD */
1408 	for (i = 0; i < ARRAY_SIZE(gpio_suffixes); i++) {
1409 		if (con_id)
1410 			snprintf(propname, sizeof(propname), "%s-%s",
1411 				 con_id, gpio_suffixes[i]);
1412 		else
1413 			snprintf(propname, sizeof(propname), "%s",
1414 				 gpio_suffixes[i]);
1415 
1416 		ret = acpi_dev_get_property(adev, propname, ACPI_TYPE_ANY,
1417 					    &obj);
1418 		if (ret == 0) {
1419 			if (obj->type == ACPI_TYPE_LOCAL_REFERENCE)
1420 				count = 1;
1421 			else if (obj->type == ACPI_TYPE_PACKAGE)
1422 				count = acpi_gpio_package_count(obj);
1423 		} else if (adev->driver_gpios) {
1424 			for (gm = adev->driver_gpios; gm->name; gm++)
1425 				if (strcmp(propname, gm->name) == 0) {
1426 					count = gm->size;
1427 					break;
1428 				}
1429 		}
1430 		if (count > 0)
1431 			break;
1432 	}
1433 
1434 	/* Then from plain _CRS GPIOs */
1435 	if (count < 0) {
1436 		struct list_head resource_list;
1437 		unsigned int crs_count = 0;
1438 
1439 		if (!acpi_can_fallback_to_crs(adev, con_id))
1440 			return count;
1441 
1442 		INIT_LIST_HEAD(&resource_list);
1443 		acpi_dev_get_resources(adev, &resource_list,
1444 				       acpi_find_gpio_count, &crs_count);
1445 		acpi_dev_free_resource_list(&resource_list);
1446 		if (crs_count > 0)
1447 			count = crs_count;
1448 	}
1449 	return count ? count : -ENOENT;
1450 }
1451 
1452 /* Run deferred acpi_gpiochip_request_irqs() */
1453 static int __init acpi_gpio_handle_deferred_request_irqs(void)
1454 {
1455 	struct acpi_gpio_chip *acpi_gpio, *tmp;
1456 
1457 	mutex_lock(&acpi_gpio_deferred_req_irqs_lock);
1458 	list_for_each_entry_safe(acpi_gpio, tmp,
1459 				 &acpi_gpio_deferred_req_irqs_list,
1460 				 deferred_req_irqs_list_entry)
1461 		acpi_gpiochip_request_irqs(acpi_gpio);
1462 
1463 	acpi_gpio_deferred_req_irqs_done = true;
1464 	mutex_unlock(&acpi_gpio_deferred_req_irqs_lock);
1465 
1466 	return 0;
1467 }
1468 /* We must use _sync so that this runs after the first deferred_probe run */
1469 late_initcall_sync(acpi_gpio_handle_deferred_request_irqs);
1470 
1471 static const struct dmi_system_id gpiolib_acpi_quirks[] __initconst = {
1472 	{
1473 		/*
1474 		 * The Minix Neo Z83-4 has a micro-USB-B id-pin handler for
1475 		 * a non existing micro-USB-B connector which puts the HDMI
1476 		 * DDC pins in GPIO mode, breaking HDMI support.
1477 		 */
1478 		.matches = {
1479 			DMI_MATCH(DMI_SYS_VENDOR, "MINIX"),
1480 			DMI_MATCH(DMI_PRODUCT_NAME, "Z83-4"),
1481 		},
1482 		.driver_data = &(struct acpi_gpiolib_dmi_quirk) {
1483 			.no_edge_events_on_boot = true,
1484 		},
1485 	},
1486 	{
1487 		/*
1488 		 * The Terra Pad 1061 has a micro-USB-B id-pin handler, which
1489 		 * instead of controlling the actual micro-USB-B turns the 5V
1490 		 * boost for its USB-A connector off. The actual micro-USB-B
1491 		 * connector is wired for charging only.
1492 		 */
1493 		.matches = {
1494 			DMI_MATCH(DMI_SYS_VENDOR, "Wortmann_AG"),
1495 			DMI_MATCH(DMI_PRODUCT_NAME, "TERRA_PAD_1061"),
1496 		},
1497 		.driver_data = &(struct acpi_gpiolib_dmi_quirk) {
1498 			.no_edge_events_on_boot = true,
1499 		},
1500 	},
1501 	{
1502 		/*
1503 		 * The Dell Venue 10 Pro 5055, with Bay Trail SoC + TI PMIC uses an
1504 		 * external embedded-controller connected via I2C + an ACPI GPIO
1505 		 * event handler on INT33FFC:02 pin 12, causing spurious wakeups.
1506 		 */
1507 		.matches = {
1508 			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
1509 			DMI_MATCH(DMI_PRODUCT_NAME, "Venue 10 Pro 5055"),
1510 		},
1511 		.driver_data = &(struct acpi_gpiolib_dmi_quirk) {
1512 			.ignore_wake = "INT33FC:02@12",
1513 		},
1514 	},
1515 	{
1516 		/*
1517 		 * HP X2 10 models with Cherry Trail SoC + TI PMIC use an
1518 		 * external embedded-controller connected via I2C + an ACPI GPIO
1519 		 * event handler on INT33FF:01 pin 0, causing spurious wakeups.
1520 		 * When suspending by closing the LID, the power to the USB
1521 		 * keyboard is turned off, causing INT0002 ACPI events to
1522 		 * trigger once the XHCI controller notices the keyboard is
1523 		 * gone. So INT0002 events cause spurious wakeups too. Ignoring
1524 		 * EC wakes breaks wakeup when opening the lid, the user needs
1525 		 * to press the power-button to wakeup the system. The
1526 		 * alternative is suspend simply not working, which is worse.
1527 		 */
1528 		.matches = {
1529 			DMI_MATCH(DMI_SYS_VENDOR, "HP"),
1530 			DMI_MATCH(DMI_PRODUCT_NAME, "HP x2 Detachable 10-p0XX"),
1531 		},
1532 		.driver_data = &(struct acpi_gpiolib_dmi_quirk) {
1533 			.ignore_wake = "INT33FF:01@0,INT0002:00@2",
1534 		},
1535 	},
1536 	{
1537 		/*
1538 		 * HP X2 10 models with Bay Trail SoC + AXP288 PMIC use an
1539 		 * external embedded-controller connected via I2C + an ACPI GPIO
1540 		 * event handler on INT33FC:02 pin 28, causing spurious wakeups.
1541 		 */
1542 		.matches = {
1543 			DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
1544 			DMI_MATCH(DMI_PRODUCT_NAME, "HP Pavilion x2 Detachable"),
1545 			DMI_MATCH(DMI_BOARD_NAME, "815D"),
1546 		},
1547 		.driver_data = &(struct acpi_gpiolib_dmi_quirk) {
1548 			.ignore_wake = "INT33FC:02@28",
1549 		},
1550 	},
1551 	{
1552 		/*
1553 		 * HP X2 10 models with Cherry Trail SoC + AXP288 PMIC use an
1554 		 * external embedded-controller connected via I2C + an ACPI GPIO
1555 		 * event handler on INT33FF:01 pin 0, causing spurious wakeups.
1556 		 */
1557 		.matches = {
1558 			DMI_MATCH(DMI_SYS_VENDOR, "HP"),
1559 			DMI_MATCH(DMI_PRODUCT_NAME, "HP Pavilion x2 Detachable"),
1560 			DMI_MATCH(DMI_BOARD_NAME, "813E"),
1561 		},
1562 		.driver_data = &(struct acpi_gpiolib_dmi_quirk) {
1563 			.ignore_wake = "INT33FF:01@0",
1564 		},
1565 	},
1566 	{} /* Terminating entry */
1567 };
1568 
1569 static int __init acpi_gpio_setup_params(void)
1570 {
1571 	const struct acpi_gpiolib_dmi_quirk *quirk = NULL;
1572 	const struct dmi_system_id *id;
1573 
1574 	id = dmi_first_match(gpiolib_acpi_quirks);
1575 	if (id)
1576 		quirk = id->driver_data;
1577 
1578 	if (run_edge_events_on_boot < 0) {
1579 		if (quirk && quirk->no_edge_events_on_boot)
1580 			run_edge_events_on_boot = 0;
1581 		else
1582 			run_edge_events_on_boot = 1;
1583 	}
1584 
1585 	if (ignore_wake == NULL && quirk && quirk->ignore_wake)
1586 		ignore_wake = quirk->ignore_wake;
1587 
1588 	return 0;
1589 }
1590 
1591 /* Directly after dmi_setup() which runs as core_initcall() */
1592 postcore_initcall(acpi_gpio_setup_params);
1593