xref: /openbmc/linux/drivers/gpio/gpiolib-acpi.c (revision 808643ea)
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 		gpiochip_free_own_desc(desc);
317 
318 	return ret ? ERR_PTR(ret) : desc;
319 }
320 
321 static bool acpi_gpio_in_ignore_list(const char *controller_in, int pin_in)
322 {
323 	const char *controller, *pin_str;
324 	int len, pin;
325 	char *endp;
326 
327 	controller = ignore_wake;
328 	while (controller) {
329 		pin_str = strchr(controller, '@');
330 		if (!pin_str)
331 			goto err;
332 
333 		len = pin_str - controller;
334 		if (len == strlen(controller_in) &&
335 		    strncmp(controller, controller_in, len) == 0) {
336 			pin = simple_strtoul(pin_str + 1, &endp, 10);
337 			if (*endp != 0 && *endp != ',')
338 				goto err;
339 
340 			if (pin == pin_in)
341 				return true;
342 		}
343 
344 		controller = strchr(controller, ',');
345 		if (controller)
346 			controller++;
347 	}
348 
349 	return false;
350 err:
351 	pr_err_once("Error invalid value for gpiolib_acpi.ignore_wake: %s\n",
352 		    ignore_wake);
353 	return false;
354 }
355 
356 static bool acpi_gpio_irq_is_wake(struct device *parent,
357 				  struct acpi_resource_gpio *agpio)
358 {
359 	int pin = agpio->pin_table[0];
360 
361 	if (agpio->wake_capable != ACPI_WAKE_CAPABLE)
362 		return false;
363 
364 	if (acpi_gpio_in_ignore_list(dev_name(parent), pin)) {
365 		dev_info(parent, "Ignoring wakeup on pin %d\n", pin);
366 		return false;
367 	}
368 
369 	return true;
370 }
371 
372 /* Always returns AE_OK so that we keep looping over the resources */
373 static acpi_status acpi_gpiochip_alloc_event(struct acpi_resource *ares,
374 					     void *context)
375 {
376 	struct acpi_gpio_chip *acpi_gpio = context;
377 	struct gpio_chip *chip = acpi_gpio->chip;
378 	struct acpi_resource_gpio *agpio;
379 	acpi_handle handle, evt_handle;
380 	struct acpi_gpio_event *event;
381 	irq_handler_t handler = NULL;
382 	struct gpio_desc *desc;
383 	int ret, pin, irq;
384 
385 	if (!acpi_gpio_get_irq_resource(ares, &agpio))
386 		return AE_OK;
387 
388 	handle = ACPI_HANDLE(chip->parent);
389 	pin = agpio->pin_table[0];
390 
391 	if (pin <= 255) {
392 		char ev_name[5];
393 		sprintf(ev_name, "_%c%02hhX",
394 			agpio->triggering == ACPI_EDGE_SENSITIVE ? 'E' : 'L',
395 			pin);
396 		if (ACPI_SUCCESS(acpi_get_handle(handle, ev_name, &evt_handle)))
397 			handler = acpi_gpio_irq_handler;
398 	}
399 	if (!handler) {
400 		if (ACPI_SUCCESS(acpi_get_handle(handle, "_EVT", &evt_handle)))
401 			handler = acpi_gpio_irq_handler_evt;
402 	}
403 	if (!handler)
404 		return AE_OK;
405 
406 	desc = acpi_request_own_gpiod(chip, agpio, 0, "ACPI:Event");
407 	if (IS_ERR(desc)) {
408 		dev_err(chip->parent,
409 			"Failed to request GPIO for pin 0x%04X, err %ld\n",
410 			pin, PTR_ERR(desc));
411 		return AE_OK;
412 	}
413 
414 	ret = gpiochip_lock_as_irq(chip, pin);
415 	if (ret) {
416 		dev_err(chip->parent,
417 			"Failed to lock GPIO pin 0x%04X as interrupt, err %d\n",
418 			pin, ret);
419 		goto fail_free_desc;
420 	}
421 
422 	irq = gpiod_to_irq(desc);
423 	if (irq < 0) {
424 		dev_err(chip->parent,
425 			"Failed to translate GPIO pin 0x%04X to IRQ, err %d\n",
426 			pin, irq);
427 		goto fail_unlock_irq;
428 	}
429 
430 	event = kzalloc(sizeof(*event), GFP_KERNEL);
431 	if (!event)
432 		goto fail_unlock_irq;
433 
434 	event->irqflags = IRQF_ONESHOT;
435 	if (agpio->triggering == ACPI_LEVEL_SENSITIVE) {
436 		if (agpio->polarity == ACPI_ACTIVE_HIGH)
437 			event->irqflags |= IRQF_TRIGGER_HIGH;
438 		else
439 			event->irqflags |= IRQF_TRIGGER_LOW;
440 	} else {
441 		switch (agpio->polarity) {
442 		case ACPI_ACTIVE_HIGH:
443 			event->irqflags |= IRQF_TRIGGER_RISING;
444 			break;
445 		case ACPI_ACTIVE_LOW:
446 			event->irqflags |= IRQF_TRIGGER_FALLING;
447 			break;
448 		default:
449 			event->irqflags |= IRQF_TRIGGER_RISING |
450 					   IRQF_TRIGGER_FALLING;
451 			break;
452 		}
453 	}
454 
455 	event->handle = evt_handle;
456 	event->handler = handler;
457 	event->irq = irq;
458 	event->irq_is_wake = acpi_gpio_irq_is_wake(chip->parent, agpio);
459 	event->pin = pin;
460 	event->desc = desc;
461 
462 	list_add_tail(&event->node, &acpi_gpio->events);
463 
464 	return AE_OK;
465 
466 fail_unlock_irq:
467 	gpiochip_unlock_as_irq(chip, pin);
468 fail_free_desc:
469 	gpiochip_free_own_desc(desc);
470 
471 	return AE_OK;
472 }
473 
474 /**
475  * acpi_gpiochip_request_interrupts() - Register isr for gpio chip ACPI events
476  * @chip:      GPIO chip
477  *
478  * ACPI5 platforms can use GPIO signaled ACPI events. These GPIO interrupts are
479  * handled by ACPI event methods which need to be called from the GPIO
480  * chip's interrupt handler. acpi_gpiochip_request_interrupts() finds out which
481  * GPIO pins have ACPI event methods and assigns interrupt handlers that calls
482  * the ACPI event methods for those pins.
483  */
484 void acpi_gpiochip_request_interrupts(struct gpio_chip *chip)
485 {
486 	struct acpi_gpio_chip *acpi_gpio;
487 	acpi_handle handle;
488 	acpi_status status;
489 	bool defer;
490 
491 	if (!chip->parent || !chip->to_irq)
492 		return;
493 
494 	handle = ACPI_HANDLE(chip->parent);
495 	if (!handle)
496 		return;
497 
498 	status = acpi_get_data(handle, acpi_gpio_chip_dh, (void **)&acpi_gpio);
499 	if (ACPI_FAILURE(status))
500 		return;
501 
502 	acpi_walk_resources(handle, "_AEI",
503 			    acpi_gpiochip_alloc_event, acpi_gpio);
504 
505 	mutex_lock(&acpi_gpio_deferred_req_irqs_lock);
506 	defer = !acpi_gpio_deferred_req_irqs_done;
507 	if (defer)
508 		list_add(&acpi_gpio->deferred_req_irqs_list_entry,
509 			 &acpi_gpio_deferred_req_irqs_list);
510 	mutex_unlock(&acpi_gpio_deferred_req_irqs_lock);
511 
512 	if (defer)
513 		return;
514 
515 	acpi_gpiochip_request_irqs(acpi_gpio);
516 }
517 EXPORT_SYMBOL_GPL(acpi_gpiochip_request_interrupts);
518 
519 /**
520  * acpi_gpiochip_free_interrupts() - Free GPIO ACPI event interrupts.
521  * @chip:      GPIO chip
522  *
523  * Free interrupts associated with GPIO ACPI event method for the given
524  * GPIO chip.
525  */
526 void acpi_gpiochip_free_interrupts(struct gpio_chip *chip)
527 {
528 	struct acpi_gpio_chip *acpi_gpio;
529 	struct acpi_gpio_event *event, *ep;
530 	acpi_handle handle;
531 	acpi_status status;
532 
533 	if (!chip->parent || !chip->to_irq)
534 		return;
535 
536 	handle = ACPI_HANDLE(chip->parent);
537 	if (!handle)
538 		return;
539 
540 	status = acpi_get_data(handle, acpi_gpio_chip_dh, (void **)&acpi_gpio);
541 	if (ACPI_FAILURE(status))
542 		return;
543 
544 	mutex_lock(&acpi_gpio_deferred_req_irqs_lock);
545 	if (!list_empty(&acpi_gpio->deferred_req_irqs_list_entry))
546 		list_del_init(&acpi_gpio->deferred_req_irqs_list_entry);
547 	mutex_unlock(&acpi_gpio_deferred_req_irqs_lock);
548 
549 	list_for_each_entry_safe_reverse(event, ep, &acpi_gpio->events, node) {
550 		if (event->irq_requested) {
551 			if (event->irq_is_wake)
552 				disable_irq_wake(event->irq);
553 
554 			free_irq(event->irq, event);
555 		}
556 
557 		gpiochip_unlock_as_irq(chip, event->pin);
558 		gpiochip_free_own_desc(event->desc);
559 		list_del(&event->node);
560 		kfree(event);
561 	}
562 }
563 EXPORT_SYMBOL_GPL(acpi_gpiochip_free_interrupts);
564 
565 int acpi_dev_add_driver_gpios(struct acpi_device *adev,
566 			      const struct acpi_gpio_mapping *gpios)
567 {
568 	if (adev && gpios) {
569 		adev->driver_gpios = gpios;
570 		return 0;
571 	}
572 	return -EINVAL;
573 }
574 EXPORT_SYMBOL_GPL(acpi_dev_add_driver_gpios);
575 
576 void acpi_dev_remove_driver_gpios(struct acpi_device *adev)
577 {
578 	if (adev)
579 		adev->driver_gpios = NULL;
580 }
581 EXPORT_SYMBOL_GPL(acpi_dev_remove_driver_gpios);
582 
583 static void devm_acpi_dev_release_driver_gpios(struct device *dev, void *res)
584 {
585 	acpi_dev_remove_driver_gpios(ACPI_COMPANION(dev));
586 }
587 
588 int devm_acpi_dev_add_driver_gpios(struct device *dev,
589 				   const struct acpi_gpio_mapping *gpios)
590 {
591 	void *res;
592 	int ret;
593 
594 	res = devres_alloc(devm_acpi_dev_release_driver_gpios, 0, GFP_KERNEL);
595 	if (!res)
596 		return -ENOMEM;
597 
598 	ret = acpi_dev_add_driver_gpios(ACPI_COMPANION(dev), gpios);
599 	if (ret) {
600 		devres_free(res);
601 		return ret;
602 	}
603 	devres_add(dev, res);
604 	return 0;
605 }
606 EXPORT_SYMBOL_GPL(devm_acpi_dev_add_driver_gpios);
607 
608 void devm_acpi_dev_remove_driver_gpios(struct device *dev)
609 {
610 	WARN_ON(devres_release(dev, devm_acpi_dev_release_driver_gpios, NULL, NULL));
611 }
612 EXPORT_SYMBOL_GPL(devm_acpi_dev_remove_driver_gpios);
613 
614 static bool acpi_get_driver_gpio_data(struct acpi_device *adev,
615 				      const char *name, int index,
616 				      struct fwnode_reference_args *args,
617 				      unsigned int *quirks)
618 {
619 	const struct acpi_gpio_mapping *gm;
620 
621 	if (!adev->driver_gpios)
622 		return false;
623 
624 	for (gm = adev->driver_gpios; gm->name; gm++)
625 		if (!strcmp(name, gm->name) && gm->data && index < gm->size) {
626 			const struct acpi_gpio_params *par = gm->data + index;
627 
628 			args->fwnode = acpi_fwnode_handle(adev);
629 			args->args[0] = par->crs_entry_index;
630 			args->args[1] = par->line_index;
631 			args->args[2] = par->active_low;
632 			args->nargs = 3;
633 
634 			*quirks = gm->quirks;
635 			return true;
636 		}
637 
638 	return false;
639 }
640 
641 static int
642 __acpi_gpio_update_gpiod_flags(enum gpiod_flags *flags, enum gpiod_flags update)
643 {
644 	const enum gpiod_flags mask =
645 		GPIOD_FLAGS_BIT_DIR_SET | GPIOD_FLAGS_BIT_DIR_OUT |
646 		GPIOD_FLAGS_BIT_DIR_VAL;
647 	int ret = 0;
648 
649 	/*
650 	 * Check if the BIOS has IoRestriction with explicitly set direction
651 	 * and update @flags accordingly. Otherwise use whatever caller asked
652 	 * for.
653 	 */
654 	if (update & GPIOD_FLAGS_BIT_DIR_SET) {
655 		enum gpiod_flags diff = *flags ^ update;
656 
657 		/*
658 		 * Check if caller supplied incompatible GPIO initialization
659 		 * flags.
660 		 *
661 		 * Return %-EINVAL to notify that firmware has different
662 		 * settings and we are going to use them.
663 		 */
664 		if (((*flags & GPIOD_FLAGS_BIT_DIR_SET) && (diff & GPIOD_FLAGS_BIT_DIR_OUT)) ||
665 		    ((*flags & GPIOD_FLAGS_BIT_DIR_OUT) && (diff & GPIOD_FLAGS_BIT_DIR_VAL)))
666 			ret = -EINVAL;
667 		*flags = (*flags & ~mask) | (update & mask);
668 	}
669 	return ret;
670 }
671 
672 int
673 acpi_gpio_update_gpiod_flags(enum gpiod_flags *flags, struct acpi_gpio_info *info)
674 {
675 	struct device *dev = &info->adev->dev;
676 	enum gpiod_flags old = *flags;
677 	int ret;
678 
679 	ret = __acpi_gpio_update_gpiod_flags(&old, info->flags);
680 	if (info->quirks & ACPI_GPIO_QUIRK_NO_IO_RESTRICTION) {
681 		if (ret)
682 			dev_warn(dev, FW_BUG "GPIO not in correct mode, fixing\n");
683 	} else {
684 		if (ret)
685 			dev_dbg(dev, "Override GPIO initialization flags\n");
686 		*flags = old;
687 	}
688 
689 	return ret;
690 }
691 
692 int acpi_gpio_update_gpiod_lookup_flags(unsigned long *lookupflags,
693 					struct acpi_gpio_info *info)
694 {
695 	switch (info->pin_config) {
696 	case ACPI_PIN_CONFIG_PULLUP:
697 		*lookupflags |= GPIO_PULL_UP;
698 		break;
699 	case ACPI_PIN_CONFIG_PULLDOWN:
700 		*lookupflags |= GPIO_PULL_DOWN;
701 		break;
702 	default:
703 		break;
704 	}
705 
706 	if (info->polarity == GPIO_ACTIVE_LOW)
707 		*lookupflags |= GPIO_ACTIVE_LOW;
708 
709 	return 0;
710 }
711 
712 struct acpi_gpio_lookup {
713 	struct acpi_gpio_info info;
714 	int index;
715 	u16 pin_index;
716 	bool active_low;
717 	struct gpio_desc *desc;
718 	int n;
719 };
720 
721 static int acpi_populate_gpio_lookup(struct acpi_resource *ares, void *data)
722 {
723 	struct acpi_gpio_lookup *lookup = data;
724 
725 	if (ares->type != ACPI_RESOURCE_TYPE_GPIO)
726 		return 1;
727 
728 	if (!lookup->desc) {
729 		const struct acpi_resource_gpio *agpio = &ares->data.gpio;
730 		bool gpioint = agpio->connection_type == ACPI_RESOURCE_GPIO_TYPE_INT;
731 		struct gpio_desc *desc;
732 		u16 pin_index;
733 
734 		if (lookup->info.quirks & ACPI_GPIO_QUIRK_ONLY_GPIOIO && gpioint)
735 			lookup->index++;
736 
737 		if (lookup->n++ != lookup->index)
738 			return 1;
739 
740 		pin_index = lookup->pin_index;
741 		if (pin_index >= agpio->pin_table_length)
742 			return 1;
743 
744 		if (lookup->info.quirks & ACPI_GPIO_QUIRK_ABSOLUTE_NUMBER)
745 			desc = gpio_to_desc(agpio->pin_table[pin_index]);
746 		else
747 			desc = acpi_get_gpiod(agpio->resource_source.string_ptr,
748 					      agpio->pin_table[pin_index]);
749 		lookup->desc = desc;
750 		lookup->info.pin_config = agpio->pin_config;
751 		lookup->info.debounce = agpio->debounce_timeout;
752 		lookup->info.gpioint = gpioint;
753 
754 		/*
755 		 * Polarity and triggering are only specified for GpioInt
756 		 * resource.
757 		 * Note: we expect here:
758 		 * - ACPI_ACTIVE_LOW == GPIO_ACTIVE_LOW
759 		 * - ACPI_ACTIVE_HIGH == GPIO_ACTIVE_HIGH
760 		 */
761 		if (lookup->info.gpioint) {
762 			lookup->info.polarity = agpio->polarity;
763 			lookup->info.triggering = agpio->triggering;
764 		} else {
765 			lookup->info.polarity = lookup->active_low;
766 		}
767 
768 		lookup->info.flags = acpi_gpio_to_gpiod_flags(agpio, lookup->info.polarity);
769 	}
770 
771 	return 1;
772 }
773 
774 static int acpi_gpio_resource_lookup(struct acpi_gpio_lookup *lookup,
775 				     struct acpi_gpio_info *info)
776 {
777 	struct acpi_device *adev = lookup->info.adev;
778 	struct list_head res_list;
779 	int ret;
780 
781 	INIT_LIST_HEAD(&res_list);
782 
783 	ret = acpi_dev_get_resources(adev, &res_list,
784 				     acpi_populate_gpio_lookup,
785 				     lookup);
786 	if (ret < 0)
787 		return ret;
788 
789 	acpi_dev_free_resource_list(&res_list);
790 
791 	if (!lookup->desc)
792 		return -ENOENT;
793 
794 	if (info)
795 		*info = lookup->info;
796 	return 0;
797 }
798 
799 static int acpi_gpio_property_lookup(struct fwnode_handle *fwnode,
800 				     const char *propname, int index,
801 				     struct acpi_gpio_lookup *lookup)
802 {
803 	struct fwnode_reference_args args;
804 	unsigned int quirks = 0;
805 	int ret;
806 
807 	memset(&args, 0, sizeof(args));
808 	ret = __acpi_node_get_property_reference(fwnode, propname, index, 3,
809 						 &args);
810 	if (ret) {
811 		struct acpi_device *adev = to_acpi_device_node(fwnode);
812 
813 		if (!adev)
814 			return ret;
815 
816 		if (!acpi_get_driver_gpio_data(adev, propname, index, &args,
817 					       &quirks))
818 			return ret;
819 	}
820 	/*
821 	 * The property was found and resolved, so need to lookup the GPIO based
822 	 * on returned args.
823 	 */
824 	if (!to_acpi_device_node(args.fwnode))
825 		return -EINVAL;
826 	if (args.nargs != 3)
827 		return -EPROTO;
828 
829 	lookup->index = args.args[0];
830 	lookup->pin_index = args.args[1];
831 	lookup->active_low = !!args.args[2];
832 
833 	lookup->info.adev = to_acpi_device_node(args.fwnode);
834 	lookup->info.quirks = quirks;
835 
836 	return 0;
837 }
838 
839 /**
840  * acpi_get_gpiod_by_index() - get a GPIO descriptor from device resources
841  * @adev: pointer to a ACPI device to get GPIO from
842  * @propname: Property name of the GPIO (optional)
843  * @index: index of GpioIo/GpioInt resource (starting from %0)
844  * @info: info pointer to fill in (optional)
845  *
846  * Function goes through ACPI resources for @adev and based on @index looks
847  * up a GpioIo/GpioInt resource, translates it to the Linux GPIO descriptor,
848  * and returns it. @index matches GpioIo/GpioInt resources only so if there
849  * are total %3 GPIO resources, the index goes from %0 to %2.
850  *
851  * If @propname is specified the GPIO is looked using device property. In
852  * that case @index is used to select the GPIO entry in the property value
853  * (in case of multiple).
854  *
855  * If the GPIO cannot be translated or there is an error, an ERR_PTR is
856  * returned.
857  *
858  * Note: if the GPIO resource has multiple entries in the pin list, this
859  * function only returns the first.
860  */
861 static struct gpio_desc *acpi_get_gpiod_by_index(struct acpi_device *adev,
862 					  const char *propname, int index,
863 					  struct acpi_gpio_info *info)
864 {
865 	struct acpi_gpio_lookup lookup;
866 	int ret;
867 
868 	if (!adev)
869 		return ERR_PTR(-ENODEV);
870 
871 	memset(&lookup, 0, sizeof(lookup));
872 	lookup.index = index;
873 
874 	if (propname) {
875 		dev_dbg(&adev->dev, "GPIO: looking up %s\n", propname);
876 
877 		ret = acpi_gpio_property_lookup(acpi_fwnode_handle(adev),
878 						propname, index, &lookup);
879 		if (ret)
880 			return ERR_PTR(ret);
881 
882 		dev_dbg(&adev->dev, "GPIO: _DSD returned %s %d %u %u\n",
883 			dev_name(&lookup.info.adev->dev), lookup.index,
884 			lookup.pin_index, lookup.active_low);
885 	} else {
886 		dev_dbg(&adev->dev, "GPIO: looking up %d in _CRS\n", index);
887 		lookup.info.adev = adev;
888 	}
889 
890 	ret = acpi_gpio_resource_lookup(&lookup, info);
891 	return ret ? ERR_PTR(ret) : lookup.desc;
892 }
893 
894 static bool acpi_can_fallback_to_crs(struct acpi_device *adev,
895 				     const char *con_id)
896 {
897 	/* Never allow fallback if the device has properties */
898 	if (acpi_dev_has_props(adev) || adev->driver_gpios)
899 		return false;
900 
901 	return con_id == NULL;
902 }
903 
904 struct gpio_desc *acpi_find_gpio(struct device *dev,
905 				 const char *con_id,
906 				 unsigned int idx,
907 				 enum gpiod_flags *dflags,
908 				 unsigned long *lookupflags)
909 {
910 	struct acpi_device *adev = ACPI_COMPANION(dev);
911 	struct acpi_gpio_info info;
912 	struct gpio_desc *desc;
913 	char propname[32];
914 	int i;
915 
916 	/* Try first from _DSD */
917 	for (i = 0; i < ARRAY_SIZE(gpio_suffixes); i++) {
918 		if (con_id) {
919 			snprintf(propname, sizeof(propname), "%s-%s",
920 				 con_id, gpio_suffixes[i]);
921 		} else {
922 			snprintf(propname, sizeof(propname), "%s",
923 				 gpio_suffixes[i]);
924 		}
925 
926 		desc = acpi_get_gpiod_by_index(adev, propname, idx, &info);
927 		if (!IS_ERR(desc))
928 			break;
929 		if (PTR_ERR(desc) == -EPROBE_DEFER)
930 			return ERR_CAST(desc);
931 	}
932 
933 	/* Then from plain _CRS GPIOs */
934 	if (IS_ERR(desc)) {
935 		if (!acpi_can_fallback_to_crs(adev, con_id))
936 			return ERR_PTR(-ENOENT);
937 
938 		desc = acpi_get_gpiod_by_index(adev, NULL, idx, &info);
939 		if (IS_ERR(desc))
940 			return desc;
941 	}
942 
943 	if (info.gpioint &&
944 	    (*dflags == GPIOD_OUT_LOW || *dflags == GPIOD_OUT_HIGH)) {
945 		dev_dbg(dev, "refusing GpioInt() entry when doing GPIOD_OUT_* lookup\n");
946 		return ERR_PTR(-ENOENT);
947 	}
948 
949 	acpi_gpio_update_gpiod_flags(dflags, &info);
950 	acpi_gpio_update_gpiod_lookup_flags(lookupflags, &info);
951 	return desc;
952 }
953 
954 /**
955  * acpi_node_get_gpiod() - get a GPIO descriptor from ACPI resources
956  * @fwnode: pointer to an ACPI firmware node to get the GPIO information from
957  * @propname: Property name of the GPIO
958  * @index: index of GpioIo/GpioInt resource (starting from %0)
959  * @info: info pointer to fill in (optional)
960  *
961  * If @fwnode is an ACPI device object, call acpi_get_gpiod_by_index() for it.
962  * Otherwise (i.e. it is a data-only non-device object), use the property-based
963  * GPIO lookup to get to the GPIO resource with the relevant information and use
964  * that to obtain the GPIO descriptor to return.
965  *
966  * If the GPIO cannot be translated or there is an error an ERR_PTR is
967  * returned.
968  */
969 struct gpio_desc *acpi_node_get_gpiod(struct fwnode_handle *fwnode,
970 				      const char *propname, int index,
971 				      struct acpi_gpio_info *info)
972 {
973 	struct acpi_gpio_lookup lookup;
974 	struct acpi_device *adev;
975 	int ret;
976 
977 	adev = to_acpi_device_node(fwnode);
978 	if (adev)
979 		return acpi_get_gpiod_by_index(adev, propname, index, info);
980 
981 	if (!is_acpi_data_node(fwnode))
982 		return ERR_PTR(-ENODEV);
983 
984 	if (!propname)
985 		return ERR_PTR(-EINVAL);
986 
987 	memset(&lookup, 0, sizeof(lookup));
988 	lookup.index = index;
989 
990 	ret = acpi_gpio_property_lookup(fwnode, propname, index, &lookup);
991 	if (ret)
992 		return ERR_PTR(ret);
993 
994 	ret = acpi_gpio_resource_lookup(&lookup, info);
995 	return ret ? ERR_PTR(ret) : lookup.desc;
996 }
997 
998 /**
999  * acpi_dev_gpio_irq_get_by() - Find GpioInt and translate it to Linux IRQ number
1000  * @adev: pointer to a ACPI device to get IRQ from
1001  * @name: optional name of GpioInt resource
1002  * @index: index of GpioInt resource (starting from %0)
1003  *
1004  * If the device has one or more GpioInt resources, this function can be
1005  * used to translate from the GPIO offset in the resource to the Linux IRQ
1006  * number.
1007  *
1008  * The function is idempotent, though each time it runs it will configure GPIO
1009  * pin direction according to the flags in GpioInt resource.
1010  *
1011  * The function takes optional @name parameter. If the resource has a property
1012  * name, then only those will be taken into account.
1013  *
1014  * Return: Linux IRQ number (> %0) on success, negative errno on failure.
1015  */
1016 int acpi_dev_gpio_irq_get_by(struct acpi_device *adev, const char *name, int index)
1017 {
1018 	int idx, i;
1019 	unsigned int irq_flags;
1020 	int ret;
1021 
1022 	for (i = 0, idx = 0; idx <= index; i++) {
1023 		struct acpi_gpio_info info;
1024 		struct gpio_desc *desc;
1025 
1026 		desc = acpi_get_gpiod_by_index(adev, name, i, &info);
1027 
1028 		/* Ignore -EPROBE_DEFER, it only matters if idx matches */
1029 		if (IS_ERR(desc) && PTR_ERR(desc) != -EPROBE_DEFER)
1030 			return PTR_ERR(desc);
1031 
1032 		if (info.gpioint && idx++ == index) {
1033 			unsigned long lflags = GPIO_LOOKUP_FLAGS_DEFAULT;
1034 			enum gpiod_flags dflags = GPIOD_ASIS;
1035 			char label[32];
1036 			int irq;
1037 
1038 			if (IS_ERR(desc))
1039 				return PTR_ERR(desc);
1040 
1041 			irq = gpiod_to_irq(desc);
1042 			if (irq < 0)
1043 				return irq;
1044 
1045 			acpi_gpio_update_gpiod_flags(&dflags, &info);
1046 			acpi_gpio_update_gpiod_lookup_flags(&lflags, &info);
1047 
1048 			snprintf(label, sizeof(label), "GpioInt() %d", index);
1049 			ret = gpiod_configure_flags(desc, label, lflags, dflags);
1050 			if (ret < 0)
1051 				return ret;
1052 
1053 			ret = gpio_set_debounce_timeout(desc, info.debounce);
1054 			if (ret)
1055 				return ret;
1056 
1057 			irq_flags = acpi_dev_get_irq_type(info.triggering,
1058 							  info.polarity);
1059 
1060 			/* Set type if specified and different than the current one */
1061 			if (irq_flags != IRQ_TYPE_NONE &&
1062 			    irq_flags != irq_get_trigger_type(irq))
1063 				irq_set_irq_type(irq, irq_flags);
1064 
1065 			return irq;
1066 		}
1067 
1068 	}
1069 	return -ENOENT;
1070 }
1071 EXPORT_SYMBOL_GPL(acpi_dev_gpio_irq_get_by);
1072 
1073 static acpi_status
1074 acpi_gpio_adr_space_handler(u32 function, acpi_physical_address address,
1075 			    u32 bits, u64 *value, void *handler_context,
1076 			    void *region_context)
1077 {
1078 	struct acpi_gpio_chip *achip = region_context;
1079 	struct gpio_chip *chip = achip->chip;
1080 	struct acpi_resource_gpio *agpio;
1081 	struct acpi_resource *ares;
1082 	u16 pin_index = address;
1083 	acpi_status status;
1084 	int length;
1085 	int i;
1086 
1087 	status = acpi_buffer_to_resource(achip->conn_info.connection,
1088 					 achip->conn_info.length, &ares);
1089 	if (ACPI_FAILURE(status))
1090 		return status;
1091 
1092 	if (WARN_ON(ares->type != ACPI_RESOURCE_TYPE_GPIO)) {
1093 		ACPI_FREE(ares);
1094 		return AE_BAD_PARAMETER;
1095 	}
1096 
1097 	agpio = &ares->data.gpio;
1098 
1099 	if (WARN_ON(agpio->io_restriction == ACPI_IO_RESTRICT_INPUT &&
1100 	    function == ACPI_WRITE)) {
1101 		ACPI_FREE(ares);
1102 		return AE_BAD_PARAMETER;
1103 	}
1104 
1105 	length = min_t(u16, agpio->pin_table_length, pin_index + bits);
1106 	for (i = pin_index; i < length; ++i) {
1107 		int pin = agpio->pin_table[i];
1108 		struct acpi_gpio_connection *conn;
1109 		struct gpio_desc *desc;
1110 		bool found;
1111 
1112 		mutex_lock(&achip->conn_lock);
1113 
1114 		found = false;
1115 		list_for_each_entry(conn, &achip->conns, node) {
1116 			if (conn->pin == pin) {
1117 				found = true;
1118 				desc = conn->desc;
1119 				break;
1120 			}
1121 		}
1122 
1123 		/*
1124 		 * The same GPIO can be shared between operation region and
1125 		 * event but only if the access here is ACPI_READ. In that
1126 		 * case we "borrow" the event GPIO instead.
1127 		 */
1128 		if (!found && agpio->shareable == ACPI_SHARED &&
1129 		     function == ACPI_READ) {
1130 			struct acpi_gpio_event *event;
1131 
1132 			list_for_each_entry(event, &achip->events, node) {
1133 				if (event->pin == pin) {
1134 					desc = event->desc;
1135 					found = true;
1136 					break;
1137 				}
1138 			}
1139 		}
1140 
1141 		if (!found) {
1142 			desc = acpi_request_own_gpiod(chip, agpio, i, "ACPI:OpRegion");
1143 			if (IS_ERR(desc)) {
1144 				mutex_unlock(&achip->conn_lock);
1145 				status = AE_ERROR;
1146 				goto out;
1147 			}
1148 
1149 			conn = kzalloc(sizeof(*conn), GFP_KERNEL);
1150 			if (!conn) {
1151 				gpiochip_free_own_desc(desc);
1152 				mutex_unlock(&achip->conn_lock);
1153 				status = AE_NO_MEMORY;
1154 				goto out;
1155 			}
1156 
1157 			conn->pin = pin;
1158 			conn->desc = desc;
1159 			list_add_tail(&conn->node, &achip->conns);
1160 		}
1161 
1162 		mutex_unlock(&achip->conn_lock);
1163 
1164 		if (function == ACPI_WRITE)
1165 			gpiod_set_raw_value_cansleep(desc, !!(*value & BIT(i)));
1166 		else
1167 			*value |= (u64)gpiod_get_raw_value_cansleep(desc) << i;
1168 	}
1169 
1170 out:
1171 	ACPI_FREE(ares);
1172 	return status;
1173 }
1174 
1175 static void acpi_gpiochip_request_regions(struct acpi_gpio_chip *achip)
1176 {
1177 	struct gpio_chip *chip = achip->chip;
1178 	acpi_handle handle = ACPI_HANDLE(chip->parent);
1179 	acpi_status status;
1180 
1181 	INIT_LIST_HEAD(&achip->conns);
1182 	mutex_init(&achip->conn_lock);
1183 	status = acpi_install_address_space_handler(handle, ACPI_ADR_SPACE_GPIO,
1184 						    acpi_gpio_adr_space_handler,
1185 						    NULL, achip);
1186 	if (ACPI_FAILURE(status))
1187 		dev_err(chip->parent,
1188 		        "Failed to install GPIO OpRegion handler\n");
1189 }
1190 
1191 static void acpi_gpiochip_free_regions(struct acpi_gpio_chip *achip)
1192 {
1193 	struct gpio_chip *chip = achip->chip;
1194 	acpi_handle handle = ACPI_HANDLE(chip->parent);
1195 	struct acpi_gpio_connection *conn, *tmp;
1196 	acpi_status status;
1197 
1198 	status = acpi_remove_address_space_handler(handle, ACPI_ADR_SPACE_GPIO,
1199 						   acpi_gpio_adr_space_handler);
1200 	if (ACPI_FAILURE(status)) {
1201 		dev_err(chip->parent,
1202 			"Failed to remove GPIO OpRegion handler\n");
1203 		return;
1204 	}
1205 
1206 	list_for_each_entry_safe_reverse(conn, tmp, &achip->conns, node) {
1207 		gpiochip_free_own_desc(conn->desc);
1208 		list_del(&conn->node);
1209 		kfree(conn);
1210 	}
1211 }
1212 
1213 static struct gpio_desc *
1214 acpi_gpiochip_parse_own_gpio(struct acpi_gpio_chip *achip,
1215 			     struct fwnode_handle *fwnode,
1216 			     const char **name,
1217 			     unsigned long *lflags,
1218 			     enum gpiod_flags *dflags)
1219 {
1220 	struct gpio_chip *chip = achip->chip;
1221 	struct gpio_desc *desc;
1222 	u32 gpios[2];
1223 	int ret;
1224 
1225 	*lflags = GPIO_LOOKUP_FLAGS_DEFAULT;
1226 	*dflags = GPIOD_ASIS;
1227 	*name = NULL;
1228 
1229 	ret = fwnode_property_read_u32_array(fwnode, "gpios", gpios,
1230 					     ARRAY_SIZE(gpios));
1231 	if (ret < 0)
1232 		return ERR_PTR(ret);
1233 
1234 	desc = gpiochip_get_desc(chip, gpios[0]);
1235 	if (IS_ERR(desc))
1236 		return desc;
1237 
1238 	if (gpios[1])
1239 		*lflags |= GPIO_ACTIVE_LOW;
1240 
1241 	if (fwnode_property_present(fwnode, "input"))
1242 		*dflags |= GPIOD_IN;
1243 	else if (fwnode_property_present(fwnode, "output-low"))
1244 		*dflags |= GPIOD_OUT_LOW;
1245 	else if (fwnode_property_present(fwnode, "output-high"))
1246 		*dflags |= GPIOD_OUT_HIGH;
1247 	else
1248 		return ERR_PTR(-EINVAL);
1249 
1250 	fwnode_property_read_string(fwnode, "line-name", name);
1251 
1252 	return desc;
1253 }
1254 
1255 static void acpi_gpiochip_scan_gpios(struct acpi_gpio_chip *achip)
1256 {
1257 	struct gpio_chip *chip = achip->chip;
1258 	struct fwnode_handle *fwnode;
1259 
1260 	device_for_each_child_node(chip->parent, fwnode) {
1261 		unsigned long lflags;
1262 		enum gpiod_flags dflags;
1263 		struct gpio_desc *desc;
1264 		const char *name;
1265 		int ret;
1266 
1267 		if (!fwnode_property_present(fwnode, "gpio-hog"))
1268 			continue;
1269 
1270 		desc = acpi_gpiochip_parse_own_gpio(achip, fwnode, &name,
1271 						    &lflags, &dflags);
1272 		if (IS_ERR(desc))
1273 			continue;
1274 
1275 		ret = gpiod_hog(desc, name, lflags, dflags);
1276 		if (ret) {
1277 			dev_err(chip->parent, "Failed to hog GPIO\n");
1278 			fwnode_handle_put(fwnode);
1279 			return;
1280 		}
1281 	}
1282 }
1283 
1284 void acpi_gpiochip_add(struct gpio_chip *chip)
1285 {
1286 	struct acpi_gpio_chip *acpi_gpio;
1287 	struct acpi_device *adev;
1288 	acpi_status status;
1289 
1290 	if (!chip || !chip->parent)
1291 		return;
1292 
1293 	adev = ACPI_COMPANION(chip->parent);
1294 	if (!adev)
1295 		return;
1296 
1297 	acpi_gpio = kzalloc(sizeof(*acpi_gpio), GFP_KERNEL);
1298 	if (!acpi_gpio) {
1299 		dev_err(chip->parent,
1300 			"Failed to allocate memory for ACPI GPIO chip\n");
1301 		return;
1302 	}
1303 
1304 	acpi_gpio->chip = chip;
1305 	INIT_LIST_HEAD(&acpi_gpio->events);
1306 	INIT_LIST_HEAD(&acpi_gpio->deferred_req_irqs_list_entry);
1307 
1308 	status = acpi_attach_data(adev->handle, acpi_gpio_chip_dh, acpi_gpio);
1309 	if (ACPI_FAILURE(status)) {
1310 		dev_err(chip->parent, "Failed to attach ACPI GPIO chip\n");
1311 		kfree(acpi_gpio);
1312 		return;
1313 	}
1314 
1315 	acpi_gpiochip_request_regions(acpi_gpio);
1316 	acpi_gpiochip_scan_gpios(acpi_gpio);
1317 	acpi_dev_clear_dependencies(adev);
1318 }
1319 
1320 void acpi_gpiochip_remove(struct gpio_chip *chip)
1321 {
1322 	struct acpi_gpio_chip *acpi_gpio;
1323 	acpi_handle handle;
1324 	acpi_status status;
1325 
1326 	if (!chip || !chip->parent)
1327 		return;
1328 
1329 	handle = ACPI_HANDLE(chip->parent);
1330 	if (!handle)
1331 		return;
1332 
1333 	status = acpi_get_data(handle, acpi_gpio_chip_dh, (void **)&acpi_gpio);
1334 	if (ACPI_FAILURE(status)) {
1335 		dev_warn(chip->parent, "Failed to retrieve ACPI GPIO chip\n");
1336 		return;
1337 	}
1338 
1339 	acpi_gpiochip_free_regions(acpi_gpio);
1340 
1341 	acpi_detach_data(handle, acpi_gpio_chip_dh);
1342 	kfree(acpi_gpio);
1343 }
1344 
1345 void acpi_gpio_dev_init(struct gpio_chip *gc, struct gpio_device *gdev)
1346 {
1347 	/* Set default fwnode to parent's one if present */
1348 	if (gc->parent)
1349 		ACPI_COMPANION_SET(&gdev->dev, ACPI_COMPANION(gc->parent));
1350 }
1351 
1352 static int acpi_gpio_package_count(const union acpi_object *obj)
1353 {
1354 	const union acpi_object *element = obj->package.elements;
1355 	const union acpi_object *end = element + obj->package.count;
1356 	unsigned int count = 0;
1357 
1358 	while (element < end) {
1359 		switch (element->type) {
1360 		case ACPI_TYPE_LOCAL_REFERENCE:
1361 			element += 3;
1362 			fallthrough;
1363 		case ACPI_TYPE_INTEGER:
1364 			element++;
1365 			count++;
1366 			break;
1367 
1368 		default:
1369 			return -EPROTO;
1370 		}
1371 	}
1372 
1373 	return count;
1374 }
1375 
1376 static int acpi_find_gpio_count(struct acpi_resource *ares, void *data)
1377 {
1378 	unsigned int *count = data;
1379 
1380 	if (ares->type == ACPI_RESOURCE_TYPE_GPIO)
1381 		*count += ares->data.gpio.pin_table_length;
1382 
1383 	return 1;
1384 }
1385 
1386 /**
1387  * acpi_gpio_count - count the GPIOs associated with a device / function
1388  * @dev:	GPIO consumer, can be %NULL for system-global GPIOs
1389  * @con_id:	function within the GPIO consumer
1390  *
1391  * Return:
1392  * The number of GPIOs associated with a device / function or %-ENOENT,
1393  * if no GPIO has been assigned to the requested function.
1394  */
1395 int acpi_gpio_count(struct device *dev, const char *con_id)
1396 {
1397 	struct acpi_device *adev = ACPI_COMPANION(dev);
1398 	const union acpi_object *obj;
1399 	const struct acpi_gpio_mapping *gm;
1400 	int count = -ENOENT;
1401 	int ret;
1402 	char propname[32];
1403 	unsigned int i;
1404 
1405 	/* Try first from _DSD */
1406 	for (i = 0; i < ARRAY_SIZE(gpio_suffixes); i++) {
1407 		if (con_id)
1408 			snprintf(propname, sizeof(propname), "%s-%s",
1409 				 con_id, gpio_suffixes[i]);
1410 		else
1411 			snprintf(propname, sizeof(propname), "%s",
1412 				 gpio_suffixes[i]);
1413 
1414 		ret = acpi_dev_get_property(adev, propname, ACPI_TYPE_ANY,
1415 					    &obj);
1416 		if (ret == 0) {
1417 			if (obj->type == ACPI_TYPE_LOCAL_REFERENCE)
1418 				count = 1;
1419 			else if (obj->type == ACPI_TYPE_PACKAGE)
1420 				count = acpi_gpio_package_count(obj);
1421 		} else if (adev->driver_gpios) {
1422 			for (gm = adev->driver_gpios; gm->name; gm++)
1423 				if (strcmp(propname, gm->name) == 0) {
1424 					count = gm->size;
1425 					break;
1426 				}
1427 		}
1428 		if (count > 0)
1429 			break;
1430 	}
1431 
1432 	/* Then from plain _CRS GPIOs */
1433 	if (count < 0) {
1434 		struct list_head resource_list;
1435 		unsigned int crs_count = 0;
1436 
1437 		if (!acpi_can_fallback_to_crs(adev, con_id))
1438 			return count;
1439 
1440 		INIT_LIST_HEAD(&resource_list);
1441 		acpi_dev_get_resources(adev, &resource_list,
1442 				       acpi_find_gpio_count, &crs_count);
1443 		acpi_dev_free_resource_list(&resource_list);
1444 		if (crs_count > 0)
1445 			count = crs_count;
1446 	}
1447 	return count ? count : -ENOENT;
1448 }
1449 
1450 /* Run deferred acpi_gpiochip_request_irqs() */
1451 static int __init acpi_gpio_handle_deferred_request_irqs(void)
1452 {
1453 	struct acpi_gpio_chip *acpi_gpio, *tmp;
1454 
1455 	mutex_lock(&acpi_gpio_deferred_req_irqs_lock);
1456 	list_for_each_entry_safe(acpi_gpio, tmp,
1457 				 &acpi_gpio_deferred_req_irqs_list,
1458 				 deferred_req_irqs_list_entry)
1459 		acpi_gpiochip_request_irqs(acpi_gpio);
1460 
1461 	acpi_gpio_deferred_req_irqs_done = true;
1462 	mutex_unlock(&acpi_gpio_deferred_req_irqs_lock);
1463 
1464 	return 0;
1465 }
1466 /* We must use _sync so that this runs after the first deferred_probe run */
1467 late_initcall_sync(acpi_gpio_handle_deferred_request_irqs);
1468 
1469 static const struct dmi_system_id gpiolib_acpi_quirks[] __initconst = {
1470 	{
1471 		/*
1472 		 * The Minix Neo Z83-4 has a micro-USB-B id-pin handler for
1473 		 * a non existing micro-USB-B connector which puts the HDMI
1474 		 * DDC pins in GPIO mode, breaking HDMI support.
1475 		 */
1476 		.matches = {
1477 			DMI_MATCH(DMI_SYS_VENDOR, "MINIX"),
1478 			DMI_MATCH(DMI_PRODUCT_NAME, "Z83-4"),
1479 		},
1480 		.driver_data = &(struct acpi_gpiolib_dmi_quirk) {
1481 			.no_edge_events_on_boot = true,
1482 		},
1483 	},
1484 	{
1485 		/*
1486 		 * The Terra Pad 1061 has a micro-USB-B id-pin handler, which
1487 		 * instead of controlling the actual micro-USB-B turns the 5V
1488 		 * boost for its USB-A connector off. The actual micro-USB-B
1489 		 * connector is wired for charging only.
1490 		 */
1491 		.matches = {
1492 			DMI_MATCH(DMI_SYS_VENDOR, "Wortmann_AG"),
1493 			DMI_MATCH(DMI_PRODUCT_NAME, "TERRA_PAD_1061"),
1494 		},
1495 		.driver_data = &(struct acpi_gpiolib_dmi_quirk) {
1496 			.no_edge_events_on_boot = true,
1497 		},
1498 	},
1499 	{
1500 		/*
1501 		 * The Dell Venue 10 Pro 5055, with Bay Trail SoC + TI PMIC uses an
1502 		 * external embedded-controller connected via I2C + an ACPI GPIO
1503 		 * event handler on INT33FFC:02 pin 12, causing spurious wakeups.
1504 		 */
1505 		.matches = {
1506 			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
1507 			DMI_MATCH(DMI_PRODUCT_NAME, "Venue 10 Pro 5055"),
1508 		},
1509 		.driver_data = &(struct acpi_gpiolib_dmi_quirk) {
1510 			.ignore_wake = "INT33FC:02@12",
1511 		},
1512 	},
1513 	{
1514 		/*
1515 		 * HP X2 10 models with Cherry Trail SoC + TI PMIC use an
1516 		 * external embedded-controller connected via I2C + an ACPI GPIO
1517 		 * event handler on INT33FF:01 pin 0, causing spurious wakeups.
1518 		 * When suspending by closing the LID, the power to the USB
1519 		 * keyboard is turned off, causing INT0002 ACPI events to
1520 		 * trigger once the XHCI controller notices the keyboard is
1521 		 * gone. So INT0002 events cause spurious wakeups too. Ignoring
1522 		 * EC wakes breaks wakeup when opening the lid, the user needs
1523 		 * to press the power-button to wakeup the system. The
1524 		 * alternative is suspend simply not working, which is worse.
1525 		 */
1526 		.matches = {
1527 			DMI_MATCH(DMI_SYS_VENDOR, "HP"),
1528 			DMI_MATCH(DMI_PRODUCT_NAME, "HP x2 Detachable 10-p0XX"),
1529 		},
1530 		.driver_data = &(struct acpi_gpiolib_dmi_quirk) {
1531 			.ignore_wake = "INT33FF:01@0,INT0002:00@2",
1532 		},
1533 	},
1534 	{
1535 		/*
1536 		 * HP X2 10 models with Bay Trail SoC + AXP288 PMIC use an
1537 		 * external embedded-controller connected via I2C + an ACPI GPIO
1538 		 * event handler on INT33FC:02 pin 28, causing spurious wakeups.
1539 		 */
1540 		.matches = {
1541 			DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
1542 			DMI_MATCH(DMI_PRODUCT_NAME, "HP Pavilion x2 Detachable"),
1543 			DMI_MATCH(DMI_BOARD_NAME, "815D"),
1544 		},
1545 		.driver_data = &(struct acpi_gpiolib_dmi_quirk) {
1546 			.ignore_wake = "INT33FC:02@28",
1547 		},
1548 	},
1549 	{
1550 		/*
1551 		 * HP X2 10 models with Cherry Trail SoC + AXP288 PMIC use an
1552 		 * external embedded-controller connected via I2C + an ACPI GPIO
1553 		 * event handler on INT33FF:01 pin 0, causing spurious wakeups.
1554 		 */
1555 		.matches = {
1556 			DMI_MATCH(DMI_SYS_VENDOR, "HP"),
1557 			DMI_MATCH(DMI_PRODUCT_NAME, "HP Pavilion x2 Detachable"),
1558 			DMI_MATCH(DMI_BOARD_NAME, "813E"),
1559 		},
1560 		.driver_data = &(struct acpi_gpiolib_dmi_quirk) {
1561 			.ignore_wake = "INT33FF:01@0",
1562 		},
1563 	},
1564 	{} /* Terminating entry */
1565 };
1566 
1567 static int __init acpi_gpio_setup_params(void)
1568 {
1569 	const struct acpi_gpiolib_dmi_quirk *quirk = NULL;
1570 	const struct dmi_system_id *id;
1571 
1572 	id = dmi_first_match(gpiolib_acpi_quirks);
1573 	if (id)
1574 		quirk = id->driver_data;
1575 
1576 	if (run_edge_events_on_boot < 0) {
1577 		if (quirk && quirk->no_edge_events_on_boot)
1578 			run_edge_events_on_boot = 0;
1579 		else
1580 			run_edge_events_on_boot = 1;
1581 	}
1582 
1583 	if (ignore_wake == NULL && quirk && quirk->ignore_wake)
1584 		ignore_wake = quirk->ignore_wake;
1585 
1586 	return 0;
1587 }
1588 
1589 /* Directly after dmi_setup() which runs as core_initcall() */
1590 postcore_initcall(acpi_gpio_setup_params);
1591