xref: /openbmc/linux/drivers/gpio/gpiolib.c (revision f5ad1c74)
1 // SPDX-License-Identifier: GPL-2.0
2 #include <linux/bitmap.h>
3 #include <linux/kernel.h>
4 #include <linux/module.h>
5 #include <linux/interrupt.h>
6 #include <linux/irq.h>
7 #include <linux/spinlock.h>
8 #include <linux/list.h>
9 #include <linux/device.h>
10 #include <linux/err.h>
11 #include <linux/debugfs.h>
12 #include <linux/seq_file.h>
13 #include <linux/gpio.h>
14 #include <linux/idr.h>
15 #include <linux/slab.h>
16 #include <linux/acpi.h>
17 #include <linux/gpio/driver.h>
18 #include <linux/gpio/machine.h>
19 #include <linux/pinctrl/consumer.h>
20 #include <linux/fs.h>
21 #include <linux/compat.h>
22 #include <linux/file.h>
23 #include <uapi/linux/gpio.h>
24 
25 #include "gpiolib.h"
26 #include "gpiolib-of.h"
27 #include "gpiolib-acpi.h"
28 #include "gpiolib-cdev.h"
29 #include "gpiolib-sysfs.h"
30 
31 #define CREATE_TRACE_POINTS
32 #include <trace/events/gpio.h>
33 
34 /* Implementation infrastructure for GPIO interfaces.
35  *
36  * The GPIO programming interface allows for inlining speed-critical
37  * get/set operations for common cases, so that access to SOC-integrated
38  * GPIOs can sometimes cost only an instruction or two per bit.
39  */
40 
41 
42 /* When debugging, extend minimal trust to callers and platform code.
43  * Also emit diagnostic messages that may help initial bringup, when
44  * board setup or driver bugs are most common.
45  *
46  * Otherwise, minimize overhead in what may be bitbanging codepaths.
47  */
48 #ifdef	DEBUG
49 #define	extra_checks	1
50 #else
51 #define	extra_checks	0
52 #endif
53 
54 /* Device and char device-related information */
55 static DEFINE_IDA(gpio_ida);
56 static dev_t gpio_devt;
57 #define GPIO_DEV_MAX 256 /* 256 GPIO chip devices supported */
58 static struct bus_type gpio_bus_type = {
59 	.name = "gpio",
60 };
61 
62 /*
63  * Number of GPIOs to use for the fast path in set array
64  */
65 #define FASTPATH_NGPIO CONFIG_GPIOLIB_FASTPATH_LIMIT
66 
67 /* gpio_lock prevents conflicts during gpio_desc[] table updates.
68  * While any GPIO is requested, its gpio_chip is not removable;
69  * each GPIO's "requested" flag serves as a lock and refcount.
70  */
71 DEFINE_SPINLOCK(gpio_lock);
72 
73 static DEFINE_MUTEX(gpio_lookup_lock);
74 static LIST_HEAD(gpio_lookup_list);
75 LIST_HEAD(gpio_devices);
76 
77 static DEFINE_MUTEX(gpio_machine_hogs_mutex);
78 static LIST_HEAD(gpio_machine_hogs);
79 
80 static void gpiochip_free_hogs(struct gpio_chip *gc);
81 static int gpiochip_add_irqchip(struct gpio_chip *gc,
82 				struct lock_class_key *lock_key,
83 				struct lock_class_key *request_key);
84 static void gpiochip_irqchip_remove(struct gpio_chip *gc);
85 static int gpiochip_irqchip_init_hw(struct gpio_chip *gc);
86 static int gpiochip_irqchip_init_valid_mask(struct gpio_chip *gc);
87 static void gpiochip_irqchip_free_valid_mask(struct gpio_chip *gc);
88 
89 static bool gpiolib_initialized;
90 
91 static inline void desc_set_label(struct gpio_desc *d, const char *label)
92 {
93 	d->label = label;
94 }
95 
96 /**
97  * gpio_to_desc - Convert a GPIO number to its descriptor
98  * @gpio: global GPIO number
99  *
100  * Returns:
101  * The GPIO descriptor associated with the given GPIO, or %NULL if no GPIO
102  * with the given number exists in the system.
103  */
104 struct gpio_desc *gpio_to_desc(unsigned gpio)
105 {
106 	struct gpio_device *gdev;
107 	unsigned long flags;
108 
109 	spin_lock_irqsave(&gpio_lock, flags);
110 
111 	list_for_each_entry(gdev, &gpio_devices, list) {
112 		if (gdev->base <= gpio &&
113 		    gdev->base + gdev->ngpio > gpio) {
114 			spin_unlock_irqrestore(&gpio_lock, flags);
115 			return &gdev->descs[gpio - gdev->base];
116 		}
117 	}
118 
119 	spin_unlock_irqrestore(&gpio_lock, flags);
120 
121 	if (!gpio_is_valid(gpio))
122 		WARN(1, "invalid GPIO %d\n", gpio);
123 
124 	return NULL;
125 }
126 EXPORT_SYMBOL_GPL(gpio_to_desc);
127 
128 /**
129  * gpiochip_get_desc - get the GPIO descriptor corresponding to the given
130  *                     hardware number for this chip
131  * @gc: GPIO chip
132  * @hwnum: hardware number of the GPIO for this chip
133  *
134  * Returns:
135  * A pointer to the GPIO descriptor or ``ERR_PTR(-EINVAL)`` if no GPIO exists
136  * in the given chip for the specified hardware number.
137  */
138 struct gpio_desc *gpiochip_get_desc(struct gpio_chip *gc,
139 				    unsigned int hwnum)
140 {
141 	struct gpio_device *gdev = gc->gpiodev;
142 
143 	if (hwnum >= gdev->ngpio)
144 		return ERR_PTR(-EINVAL);
145 
146 	return &gdev->descs[hwnum];
147 }
148 EXPORT_SYMBOL_GPL(gpiochip_get_desc);
149 
150 /**
151  * desc_to_gpio - convert a GPIO descriptor to the integer namespace
152  * @desc: GPIO descriptor
153  *
154  * This should disappear in the future but is needed since we still
155  * use GPIO numbers for error messages and sysfs nodes.
156  *
157  * Returns:
158  * The global GPIO number for the GPIO specified by its descriptor.
159  */
160 int desc_to_gpio(const struct gpio_desc *desc)
161 {
162 	return desc->gdev->base + (desc - &desc->gdev->descs[0]);
163 }
164 EXPORT_SYMBOL_GPL(desc_to_gpio);
165 
166 
167 /**
168  * gpiod_to_chip - Return the GPIO chip to which a GPIO descriptor belongs
169  * @desc:	descriptor to return the chip of
170  */
171 struct gpio_chip *gpiod_to_chip(const struct gpio_desc *desc)
172 {
173 	if (!desc || !desc->gdev)
174 		return NULL;
175 	return desc->gdev->chip;
176 }
177 EXPORT_SYMBOL_GPL(gpiod_to_chip);
178 
179 /* dynamic allocation of GPIOs, e.g. on a hotplugged device */
180 static int gpiochip_find_base(int ngpio)
181 {
182 	struct gpio_device *gdev;
183 	int base = ARCH_NR_GPIOS - ngpio;
184 
185 	list_for_each_entry_reverse(gdev, &gpio_devices, list) {
186 		/* found a free space? */
187 		if (gdev->base + gdev->ngpio <= base)
188 			break;
189 		else
190 			/* nope, check the space right before the chip */
191 			base = gdev->base - ngpio;
192 	}
193 
194 	if (gpio_is_valid(base)) {
195 		pr_debug("%s: found new base at %d\n", __func__, base);
196 		return base;
197 	} else {
198 		pr_err("%s: cannot find free range\n", __func__);
199 		return -ENOSPC;
200 	}
201 }
202 
203 /**
204  * gpiod_get_direction - return the current direction of a GPIO
205  * @desc:	GPIO to get the direction of
206  *
207  * Returns 0 for output, 1 for input, or an error code in case of error.
208  *
209  * This function may sleep if gpiod_cansleep() is true.
210  */
211 int gpiod_get_direction(struct gpio_desc *desc)
212 {
213 	struct gpio_chip *gc;
214 	unsigned offset;
215 	int ret;
216 
217 	gc = gpiod_to_chip(desc);
218 	offset = gpio_chip_hwgpio(desc);
219 
220 	/*
221 	 * Open drain emulation using input mode may incorrectly report
222 	 * input here, fix that up.
223 	 */
224 	if (test_bit(FLAG_OPEN_DRAIN, &desc->flags) &&
225 	    test_bit(FLAG_IS_OUT, &desc->flags))
226 		return 0;
227 
228 	if (!gc->get_direction)
229 		return -ENOTSUPP;
230 
231 	ret = gc->get_direction(gc, offset);
232 	if (ret < 0)
233 		return ret;
234 
235 	/* GPIOF_DIR_IN or other positive, otherwise GPIOF_DIR_OUT */
236 	if (ret > 0)
237 		ret = 1;
238 
239 	assign_bit(FLAG_IS_OUT, &desc->flags, !ret);
240 
241 	return ret;
242 }
243 EXPORT_SYMBOL_GPL(gpiod_get_direction);
244 
245 /*
246  * Add a new chip to the global chips list, keeping the list of chips sorted
247  * by range(means [base, base + ngpio - 1]) order.
248  *
249  * Return -EBUSY if the new chip overlaps with some other chip's integer
250  * space.
251  */
252 static int gpiodev_add_to_list(struct gpio_device *gdev)
253 {
254 	struct gpio_device *prev, *next;
255 
256 	if (list_empty(&gpio_devices)) {
257 		/* initial entry in list */
258 		list_add_tail(&gdev->list, &gpio_devices);
259 		return 0;
260 	}
261 
262 	next = list_entry(gpio_devices.next, struct gpio_device, list);
263 	if (gdev->base + gdev->ngpio <= next->base) {
264 		/* add before first entry */
265 		list_add(&gdev->list, &gpio_devices);
266 		return 0;
267 	}
268 
269 	prev = list_entry(gpio_devices.prev, struct gpio_device, list);
270 	if (prev->base + prev->ngpio <= gdev->base) {
271 		/* add behind last entry */
272 		list_add_tail(&gdev->list, &gpio_devices);
273 		return 0;
274 	}
275 
276 	list_for_each_entry_safe(prev, next, &gpio_devices, list) {
277 		/* at the end of the list */
278 		if (&next->list == &gpio_devices)
279 			break;
280 
281 		/* add between prev and next */
282 		if (prev->base + prev->ngpio <= gdev->base
283 				&& gdev->base + gdev->ngpio <= next->base) {
284 			list_add(&gdev->list, &prev->list);
285 			return 0;
286 		}
287 	}
288 
289 	dev_err(&gdev->dev, "GPIO integer space overlap, cannot add chip\n");
290 	return -EBUSY;
291 }
292 
293 /*
294  * Convert a GPIO name to its descriptor
295  * Note that there is no guarantee that GPIO names are globally unique!
296  * Hence this function will return, if it exists, a reference to the first GPIO
297  * line found that matches the given name.
298  */
299 static struct gpio_desc *gpio_name_to_desc(const char * const name)
300 {
301 	struct gpio_device *gdev;
302 	unsigned long flags;
303 
304 	if (!name)
305 		return NULL;
306 
307 	spin_lock_irqsave(&gpio_lock, flags);
308 
309 	list_for_each_entry(gdev, &gpio_devices, list) {
310 		int i;
311 
312 		for (i = 0; i != gdev->ngpio; ++i) {
313 			struct gpio_desc *desc = &gdev->descs[i];
314 
315 			if (!desc->name)
316 				continue;
317 
318 			if (!strcmp(desc->name, name)) {
319 				spin_unlock_irqrestore(&gpio_lock, flags);
320 				return desc;
321 			}
322 		}
323 	}
324 
325 	spin_unlock_irqrestore(&gpio_lock, flags);
326 
327 	return NULL;
328 }
329 
330 /*
331  * Take the names from gc->names and assign them to their GPIO descriptors.
332  * Warn if a name is already used for a GPIO line on a different GPIO chip.
333  *
334  * Note that:
335  *   1. Non-unique names are still accepted,
336  *   2. Name collisions within the same GPIO chip are not reported.
337  */
338 static int gpiochip_set_desc_names(struct gpio_chip *gc)
339 {
340 	struct gpio_device *gdev = gc->gpiodev;
341 	int i;
342 
343 	/* First check all names if they are unique */
344 	for (i = 0; i != gc->ngpio; ++i) {
345 		struct gpio_desc *gpio;
346 
347 		gpio = gpio_name_to_desc(gc->names[i]);
348 		if (gpio)
349 			dev_warn(&gdev->dev,
350 				 "Detected name collision for GPIO name '%s'\n",
351 				 gc->names[i]);
352 	}
353 
354 	/* Then add all names to the GPIO descriptors */
355 	for (i = 0; i != gc->ngpio; ++i)
356 		gdev->descs[i].name = gc->names[i];
357 
358 	return 0;
359 }
360 
361 /*
362  * devprop_gpiochip_set_names - Set GPIO line names using device properties
363  * @chip: GPIO chip whose lines should be named, if possible
364  *
365  * Looks for device property "gpio-line-names" and if it exists assigns
366  * GPIO line names for the chip. The memory allocated for the assigned
367  * names belong to the underlying software node and should not be released
368  * by the caller.
369  */
370 static int devprop_gpiochip_set_names(struct gpio_chip *chip)
371 {
372 	struct gpio_device *gdev = chip->gpiodev;
373 	struct device *dev = chip->parent;
374 	const char **names;
375 	int ret, i;
376 	int count;
377 
378 	/* GPIO chip may not have a parent device whose properties we inspect. */
379 	if (!dev)
380 		return 0;
381 
382 	count = device_property_string_array_count(dev, "gpio-line-names");
383 	if (count < 0)
384 		return 0;
385 
386 	if (count > gdev->ngpio) {
387 		dev_warn(&gdev->dev, "gpio-line-names is length %d but should be at most length %d",
388 			 count, gdev->ngpio);
389 		count = gdev->ngpio;
390 	}
391 
392 	names = kcalloc(count, sizeof(*names), GFP_KERNEL);
393 	if (!names)
394 		return -ENOMEM;
395 
396 	ret = device_property_read_string_array(dev, "gpio-line-names",
397 						names, count);
398 	if (ret < 0) {
399 		dev_warn(&gdev->dev, "failed to read GPIO line names\n");
400 		kfree(names);
401 		return ret;
402 	}
403 
404 	for (i = 0; i < count; i++)
405 		gdev->descs[i].name = names[i];
406 
407 	kfree(names);
408 
409 	return 0;
410 }
411 
412 static unsigned long *gpiochip_allocate_mask(struct gpio_chip *gc)
413 {
414 	unsigned long *p;
415 
416 	p = bitmap_alloc(gc->ngpio, GFP_KERNEL);
417 	if (!p)
418 		return NULL;
419 
420 	/* Assume by default all GPIOs are valid */
421 	bitmap_fill(p, gc->ngpio);
422 
423 	return p;
424 }
425 
426 static int gpiochip_alloc_valid_mask(struct gpio_chip *gc)
427 {
428 	if (!(of_gpio_need_valid_mask(gc) || gc->init_valid_mask))
429 		return 0;
430 
431 	gc->valid_mask = gpiochip_allocate_mask(gc);
432 	if (!gc->valid_mask)
433 		return -ENOMEM;
434 
435 	return 0;
436 }
437 
438 static int gpiochip_init_valid_mask(struct gpio_chip *gc)
439 {
440 	if (gc->init_valid_mask)
441 		return gc->init_valid_mask(gc,
442 					   gc->valid_mask,
443 					   gc->ngpio);
444 
445 	return 0;
446 }
447 
448 static void gpiochip_free_valid_mask(struct gpio_chip *gc)
449 {
450 	bitmap_free(gc->valid_mask);
451 	gc->valid_mask = NULL;
452 }
453 
454 static int gpiochip_add_pin_ranges(struct gpio_chip *gc)
455 {
456 	if (gc->add_pin_ranges)
457 		return gc->add_pin_ranges(gc);
458 
459 	return 0;
460 }
461 
462 bool gpiochip_line_is_valid(const struct gpio_chip *gc,
463 				unsigned int offset)
464 {
465 	/* No mask means all valid */
466 	if (likely(!gc->valid_mask))
467 		return true;
468 	return test_bit(offset, gc->valid_mask);
469 }
470 EXPORT_SYMBOL_GPL(gpiochip_line_is_valid);
471 
472 static void gpiodevice_release(struct device *dev)
473 {
474 	struct gpio_device *gdev = dev_get_drvdata(dev);
475 
476 	list_del(&gdev->list);
477 	ida_free(&gpio_ida, gdev->id);
478 	kfree_const(gdev->label);
479 	kfree(gdev->descs);
480 	kfree(gdev);
481 }
482 
483 #ifdef CONFIG_GPIO_CDEV
484 #define gcdev_register(gdev, devt)	gpiolib_cdev_register((gdev), (devt))
485 #define gcdev_unregister(gdev)		gpiolib_cdev_unregister((gdev))
486 #else
487 /*
488  * gpiolib_cdev_register() indirectly calls device_add(), which is still
489  * required even when cdev is not selected.
490  */
491 #define gcdev_register(gdev, devt)	device_add(&(gdev)->dev)
492 #define gcdev_unregister(gdev)		device_del(&(gdev)->dev)
493 #endif
494 
495 static int gpiochip_setup_dev(struct gpio_device *gdev)
496 {
497 	int ret;
498 
499 	ret = gcdev_register(gdev, gpio_devt);
500 	if (ret)
501 		return ret;
502 
503 	ret = gpiochip_sysfs_register(gdev);
504 	if (ret)
505 		goto err_remove_device;
506 
507 	/* From this point, the .release() function cleans up gpio_device */
508 	gdev->dev.release = gpiodevice_release;
509 	dev_dbg(&gdev->dev, "registered GPIOs %d to %d on %s\n", gdev->base,
510 		gdev->base + gdev->ngpio - 1, gdev->chip->label ? : "generic");
511 
512 	return 0;
513 
514 err_remove_device:
515 	gcdev_unregister(gdev);
516 	return ret;
517 }
518 
519 static void gpiochip_machine_hog(struct gpio_chip *gc, struct gpiod_hog *hog)
520 {
521 	struct gpio_desc *desc;
522 	int rv;
523 
524 	desc = gpiochip_get_desc(gc, hog->chip_hwnum);
525 	if (IS_ERR(desc)) {
526 		chip_err(gc, "%s: unable to get GPIO desc: %ld\n", __func__,
527 			 PTR_ERR(desc));
528 		return;
529 	}
530 
531 	if (test_bit(FLAG_IS_HOGGED, &desc->flags))
532 		return;
533 
534 	rv = gpiod_hog(desc, hog->line_name, hog->lflags, hog->dflags);
535 	if (rv)
536 		gpiod_err(desc, "%s: unable to hog GPIO line (%s:%u): %d\n",
537 			  __func__, gc->label, hog->chip_hwnum, rv);
538 }
539 
540 static void machine_gpiochip_add(struct gpio_chip *gc)
541 {
542 	struct gpiod_hog *hog;
543 
544 	mutex_lock(&gpio_machine_hogs_mutex);
545 
546 	list_for_each_entry(hog, &gpio_machine_hogs, list) {
547 		if (!strcmp(gc->label, hog->chip_label))
548 			gpiochip_machine_hog(gc, hog);
549 	}
550 
551 	mutex_unlock(&gpio_machine_hogs_mutex);
552 }
553 
554 static void gpiochip_setup_devs(void)
555 {
556 	struct gpio_device *gdev;
557 	int ret;
558 
559 	list_for_each_entry(gdev, &gpio_devices, list) {
560 		ret = gpiochip_setup_dev(gdev);
561 		if (ret)
562 			dev_err(&gdev->dev,
563 				"Failed to initialize gpio device (%d)\n", ret);
564 	}
565 }
566 
567 int gpiochip_add_data_with_key(struct gpio_chip *gc, void *data,
568 			       struct lock_class_key *lock_key,
569 			       struct lock_class_key *request_key)
570 {
571 	unsigned long	flags;
572 	int		ret = 0;
573 	unsigned	i;
574 	int		base = gc->base;
575 	struct gpio_device *gdev;
576 
577 	/*
578 	 * First: allocate and populate the internal stat container, and
579 	 * set up the struct device.
580 	 */
581 	gdev = kzalloc(sizeof(*gdev), GFP_KERNEL);
582 	if (!gdev)
583 		return -ENOMEM;
584 	gdev->dev.bus = &gpio_bus_type;
585 	gdev->chip = gc;
586 	gc->gpiodev = gdev;
587 	if (gc->parent) {
588 		gdev->dev.parent = gc->parent;
589 		gdev->dev.of_node = gc->parent->of_node;
590 	}
591 
592 #ifdef CONFIG_OF_GPIO
593 	/* If the gpiochip has an assigned OF node this takes precedence */
594 	if (gc->of_node)
595 		gdev->dev.of_node = gc->of_node;
596 	else
597 		gc->of_node = gdev->dev.of_node;
598 #endif
599 
600 	gdev->id = ida_alloc(&gpio_ida, GFP_KERNEL);
601 	if (gdev->id < 0) {
602 		ret = gdev->id;
603 		goto err_free_gdev;
604 	}
605 	dev_set_name(&gdev->dev, GPIOCHIP_NAME "%d", gdev->id);
606 	device_initialize(&gdev->dev);
607 	dev_set_drvdata(&gdev->dev, gdev);
608 	if (gc->parent && gc->parent->driver)
609 		gdev->owner = gc->parent->driver->owner;
610 	else if (gc->owner)
611 		/* TODO: remove chip->owner */
612 		gdev->owner = gc->owner;
613 	else
614 		gdev->owner = THIS_MODULE;
615 
616 	gdev->descs = kcalloc(gc->ngpio, sizeof(gdev->descs[0]), GFP_KERNEL);
617 	if (!gdev->descs) {
618 		ret = -ENOMEM;
619 		goto err_free_ida;
620 	}
621 
622 	if (gc->ngpio == 0) {
623 		chip_err(gc, "tried to insert a GPIO chip with zero lines\n");
624 		ret = -EINVAL;
625 		goto err_free_descs;
626 	}
627 
628 	if (gc->ngpio > FASTPATH_NGPIO)
629 		chip_warn(gc, "line cnt %u is greater than fast path cnt %u\n",
630 			  gc->ngpio, FASTPATH_NGPIO);
631 
632 	gdev->label = kstrdup_const(gc->label ?: "unknown", GFP_KERNEL);
633 	if (!gdev->label) {
634 		ret = -ENOMEM;
635 		goto err_free_descs;
636 	}
637 
638 	gdev->ngpio = gc->ngpio;
639 	gdev->data = data;
640 
641 	spin_lock_irqsave(&gpio_lock, flags);
642 
643 	/*
644 	 * TODO: this allocates a Linux GPIO number base in the global
645 	 * GPIO numberspace for this chip. In the long run we want to
646 	 * get *rid* of this numberspace and use only descriptors, but
647 	 * it may be a pipe dream. It will not happen before we get rid
648 	 * of the sysfs interface anyways.
649 	 */
650 	if (base < 0) {
651 		base = gpiochip_find_base(gc->ngpio);
652 		if (base < 0) {
653 			ret = base;
654 			spin_unlock_irqrestore(&gpio_lock, flags);
655 			goto err_free_label;
656 		}
657 		/*
658 		 * TODO: it should not be necessary to reflect the assigned
659 		 * base outside of the GPIO subsystem. Go over drivers and
660 		 * see if anyone makes use of this, else drop this and assign
661 		 * a poison instead.
662 		 */
663 		gc->base = base;
664 	}
665 	gdev->base = base;
666 
667 	ret = gpiodev_add_to_list(gdev);
668 	if (ret) {
669 		spin_unlock_irqrestore(&gpio_lock, flags);
670 		goto err_free_label;
671 	}
672 
673 	for (i = 0; i < gc->ngpio; i++)
674 		gdev->descs[i].gdev = gdev;
675 
676 	spin_unlock_irqrestore(&gpio_lock, flags);
677 
678 	BLOCKING_INIT_NOTIFIER_HEAD(&gdev->notifier);
679 
680 #ifdef CONFIG_PINCTRL
681 	INIT_LIST_HEAD(&gdev->pin_ranges);
682 #endif
683 
684 	if (gc->names)
685 		ret = gpiochip_set_desc_names(gc);
686 	else
687 		ret = devprop_gpiochip_set_names(gc);
688 	if (ret)
689 		goto err_remove_from_list;
690 
691 	ret = gpiochip_alloc_valid_mask(gc);
692 	if (ret)
693 		goto err_remove_from_list;
694 
695 	ret = of_gpiochip_add(gc);
696 	if (ret)
697 		goto err_free_gpiochip_mask;
698 
699 	ret = gpiochip_init_valid_mask(gc);
700 	if (ret)
701 		goto err_remove_of_chip;
702 
703 	for (i = 0; i < gc->ngpio; i++) {
704 		struct gpio_desc *desc = &gdev->descs[i];
705 
706 		if (gc->get_direction && gpiochip_line_is_valid(gc, i)) {
707 			assign_bit(FLAG_IS_OUT,
708 				   &desc->flags, !gc->get_direction(gc, i));
709 		} else {
710 			assign_bit(FLAG_IS_OUT,
711 				   &desc->flags, !gc->direction_input);
712 		}
713 	}
714 
715 	ret = gpiochip_add_pin_ranges(gc);
716 	if (ret)
717 		goto err_remove_of_chip;
718 
719 	acpi_gpiochip_add(gc);
720 
721 	machine_gpiochip_add(gc);
722 
723 	ret = gpiochip_irqchip_init_valid_mask(gc);
724 	if (ret)
725 		goto err_remove_acpi_chip;
726 
727 	ret = gpiochip_irqchip_init_hw(gc);
728 	if (ret)
729 		goto err_remove_acpi_chip;
730 
731 	ret = gpiochip_add_irqchip(gc, lock_key, request_key);
732 	if (ret)
733 		goto err_remove_irqchip_mask;
734 
735 	/*
736 	 * By first adding the chardev, and then adding the device,
737 	 * we get a device node entry in sysfs under
738 	 * /sys/bus/gpio/devices/gpiochipN/dev that can be used for
739 	 * coldplug of device nodes and other udev business.
740 	 * We can do this only if gpiolib has been initialized.
741 	 * Otherwise, defer until later.
742 	 */
743 	if (gpiolib_initialized) {
744 		ret = gpiochip_setup_dev(gdev);
745 		if (ret)
746 			goto err_remove_irqchip;
747 	}
748 	return 0;
749 
750 err_remove_irqchip:
751 	gpiochip_irqchip_remove(gc);
752 err_remove_irqchip_mask:
753 	gpiochip_irqchip_free_valid_mask(gc);
754 err_remove_acpi_chip:
755 	acpi_gpiochip_remove(gc);
756 err_remove_of_chip:
757 	gpiochip_free_hogs(gc);
758 	of_gpiochip_remove(gc);
759 err_free_gpiochip_mask:
760 	gpiochip_remove_pin_ranges(gc);
761 	gpiochip_free_valid_mask(gc);
762 err_remove_from_list:
763 	spin_lock_irqsave(&gpio_lock, flags);
764 	list_del(&gdev->list);
765 	spin_unlock_irqrestore(&gpio_lock, flags);
766 err_free_label:
767 	kfree_const(gdev->label);
768 err_free_descs:
769 	kfree(gdev->descs);
770 err_free_ida:
771 	ida_free(&gpio_ida, gdev->id);
772 err_free_gdev:
773 	/* failures here can mean systems won't boot... */
774 	pr_err("%s: GPIOs %d..%d (%s) failed to register, %d\n", __func__,
775 	       gdev->base, gdev->base + gdev->ngpio - 1,
776 	       gc->label ? : "generic", ret);
777 	kfree(gdev);
778 	return ret;
779 }
780 EXPORT_SYMBOL_GPL(gpiochip_add_data_with_key);
781 
782 /**
783  * gpiochip_get_data() - get per-subdriver data for the chip
784  * @gc: GPIO chip
785  *
786  * Returns:
787  * The per-subdriver data for the chip.
788  */
789 void *gpiochip_get_data(struct gpio_chip *gc)
790 {
791 	return gc->gpiodev->data;
792 }
793 EXPORT_SYMBOL_GPL(gpiochip_get_data);
794 
795 /**
796  * gpiochip_remove() - unregister a gpio_chip
797  * @gc: the chip to unregister
798  *
799  * A gpio_chip with any GPIOs still requested may not be removed.
800  */
801 void gpiochip_remove(struct gpio_chip *gc)
802 {
803 	struct gpio_device *gdev = gc->gpiodev;
804 	unsigned long	flags;
805 	unsigned int	i;
806 
807 	/* FIXME: should the legacy sysfs handling be moved to gpio_device? */
808 	gpiochip_sysfs_unregister(gdev);
809 	gpiochip_free_hogs(gc);
810 	/* Numb the device, cancelling all outstanding operations */
811 	gdev->chip = NULL;
812 	gpiochip_irqchip_remove(gc);
813 	acpi_gpiochip_remove(gc);
814 	of_gpiochip_remove(gc);
815 	gpiochip_remove_pin_ranges(gc);
816 	gpiochip_free_valid_mask(gc);
817 	/*
818 	 * We accept no more calls into the driver from this point, so
819 	 * NULL the driver data pointer
820 	 */
821 	gdev->data = NULL;
822 
823 	spin_lock_irqsave(&gpio_lock, flags);
824 	for (i = 0; i < gdev->ngpio; i++) {
825 		if (gpiochip_is_requested(gc, i))
826 			break;
827 	}
828 	spin_unlock_irqrestore(&gpio_lock, flags);
829 
830 	if (i != gdev->ngpio)
831 		dev_crit(&gdev->dev,
832 			 "REMOVING GPIOCHIP WITH GPIOS STILL REQUESTED\n");
833 
834 	/*
835 	 * The gpiochip side puts its use of the device to rest here:
836 	 * if there are no userspace clients, the chardev and device will
837 	 * be removed, else it will be dangling until the last user is
838 	 * gone.
839 	 */
840 	gcdev_unregister(gdev);
841 	put_device(&gdev->dev);
842 }
843 EXPORT_SYMBOL_GPL(gpiochip_remove);
844 
845 /**
846  * gpiochip_find() - iterator for locating a specific gpio_chip
847  * @data: data to pass to match function
848  * @match: Callback function to check gpio_chip
849  *
850  * Similar to bus_find_device.  It returns a reference to a gpio_chip as
851  * determined by a user supplied @match callback.  The callback should return
852  * 0 if the device doesn't match and non-zero if it does.  If the callback is
853  * non-zero, this function will return to the caller and not iterate over any
854  * more gpio_chips.
855  */
856 struct gpio_chip *gpiochip_find(void *data,
857 				int (*match)(struct gpio_chip *gc,
858 					     void *data))
859 {
860 	struct gpio_device *gdev;
861 	struct gpio_chip *gc = NULL;
862 	unsigned long flags;
863 
864 	spin_lock_irqsave(&gpio_lock, flags);
865 	list_for_each_entry(gdev, &gpio_devices, list)
866 		if (gdev->chip && match(gdev->chip, data)) {
867 			gc = gdev->chip;
868 			break;
869 		}
870 
871 	spin_unlock_irqrestore(&gpio_lock, flags);
872 
873 	return gc;
874 }
875 EXPORT_SYMBOL_GPL(gpiochip_find);
876 
877 static int gpiochip_match_name(struct gpio_chip *gc, void *data)
878 {
879 	const char *name = data;
880 
881 	return !strcmp(gc->label, name);
882 }
883 
884 static struct gpio_chip *find_chip_by_name(const char *name)
885 {
886 	return gpiochip_find((void *)name, gpiochip_match_name);
887 }
888 
889 #ifdef CONFIG_GPIOLIB_IRQCHIP
890 
891 /*
892  * The following is irqchip helper code for gpiochips.
893  */
894 
895 static int gpiochip_irqchip_init_hw(struct gpio_chip *gc)
896 {
897 	struct gpio_irq_chip *girq = &gc->irq;
898 
899 	if (!girq->init_hw)
900 		return 0;
901 
902 	return girq->init_hw(gc);
903 }
904 
905 static int gpiochip_irqchip_init_valid_mask(struct gpio_chip *gc)
906 {
907 	struct gpio_irq_chip *girq = &gc->irq;
908 
909 	if (!girq->init_valid_mask)
910 		return 0;
911 
912 	girq->valid_mask = gpiochip_allocate_mask(gc);
913 	if (!girq->valid_mask)
914 		return -ENOMEM;
915 
916 	girq->init_valid_mask(gc, girq->valid_mask, gc->ngpio);
917 
918 	return 0;
919 }
920 
921 static void gpiochip_irqchip_free_valid_mask(struct gpio_chip *gc)
922 {
923 	bitmap_free(gc->irq.valid_mask);
924 	gc->irq.valid_mask = NULL;
925 }
926 
927 bool gpiochip_irqchip_irq_valid(const struct gpio_chip *gc,
928 				unsigned int offset)
929 {
930 	if (!gpiochip_line_is_valid(gc, offset))
931 		return false;
932 	/* No mask means all valid */
933 	if (likely(!gc->irq.valid_mask))
934 		return true;
935 	return test_bit(offset, gc->irq.valid_mask);
936 }
937 EXPORT_SYMBOL_GPL(gpiochip_irqchip_irq_valid);
938 
939 /**
940  * gpiochip_set_cascaded_irqchip() - connects a cascaded irqchip to a gpiochip
941  * @gc: the gpiochip to set the irqchip chain to
942  * @parent_irq: the irq number corresponding to the parent IRQ for this
943  * cascaded irqchip
944  * @parent_handler: the parent interrupt handler for the accumulated IRQ
945  * coming out of the gpiochip. If the interrupt is nested rather than
946  * cascaded, pass NULL in this handler argument
947  */
948 static void gpiochip_set_cascaded_irqchip(struct gpio_chip *gc,
949 					  unsigned int parent_irq,
950 					  irq_flow_handler_t parent_handler)
951 {
952 	struct gpio_irq_chip *girq = &gc->irq;
953 	struct device *dev = &gc->gpiodev->dev;
954 
955 	if (!girq->domain) {
956 		chip_err(gc, "called %s before setting up irqchip\n",
957 			 __func__);
958 		return;
959 	}
960 
961 	if (parent_handler) {
962 		if (gc->can_sleep) {
963 			chip_err(gc,
964 				 "you cannot have chained interrupts on a chip that may sleep\n");
965 			return;
966 		}
967 		girq->parents = devm_kcalloc(dev, 1,
968 					     sizeof(*girq->parents),
969 					     GFP_KERNEL);
970 		if (!girq->parents) {
971 			chip_err(gc, "out of memory allocating parent IRQ\n");
972 			return;
973 		}
974 		girq->parents[0] = parent_irq;
975 		girq->num_parents = 1;
976 		/*
977 		 * The parent irqchip is already using the chip_data for this
978 		 * irqchip, so our callbacks simply use the handler_data.
979 		 */
980 		irq_set_chained_handler_and_data(parent_irq, parent_handler,
981 						 gc);
982 	}
983 }
984 
985 /**
986  * gpiochip_set_nested_irqchip() - connects a nested irqchip to a gpiochip
987  * @gc: the gpiochip to set the irqchip nested handler to
988  * @irqchip: the irqchip to nest to the gpiochip
989  * @parent_irq: the irq number corresponding to the parent IRQ for this
990  * nested irqchip
991  */
992 void gpiochip_set_nested_irqchip(struct gpio_chip *gc,
993 				 struct irq_chip *irqchip,
994 				 unsigned int parent_irq)
995 {
996 	gpiochip_set_cascaded_irqchip(gc, parent_irq, NULL);
997 }
998 EXPORT_SYMBOL_GPL(gpiochip_set_nested_irqchip);
999 
1000 #ifdef CONFIG_IRQ_DOMAIN_HIERARCHY
1001 
1002 /**
1003  * gpiochip_set_hierarchical_irqchip() - connects a hierarchical irqchip
1004  * to a gpiochip
1005  * @gc: the gpiochip to set the irqchip hierarchical handler to
1006  * @irqchip: the irqchip to handle this level of the hierarchy, the interrupt
1007  * will then percolate up to the parent
1008  */
1009 static void gpiochip_set_hierarchical_irqchip(struct gpio_chip *gc,
1010 					      struct irq_chip *irqchip)
1011 {
1012 	/* DT will deal with mapping each IRQ as we go along */
1013 	if (is_of_node(gc->irq.fwnode))
1014 		return;
1015 
1016 	/*
1017 	 * This is for legacy and boardfile "irqchip" fwnodes: allocate
1018 	 * irqs upfront instead of dynamically since we don't have the
1019 	 * dynamic type of allocation that hardware description languages
1020 	 * provide. Once all GPIO drivers using board files are gone from
1021 	 * the kernel we can delete this code, but for a transitional period
1022 	 * it is necessary to keep this around.
1023 	 */
1024 	if (is_fwnode_irqchip(gc->irq.fwnode)) {
1025 		int i;
1026 		int ret;
1027 
1028 		for (i = 0; i < gc->ngpio; i++) {
1029 			struct irq_fwspec fwspec;
1030 			unsigned int parent_hwirq;
1031 			unsigned int parent_type;
1032 			struct gpio_irq_chip *girq = &gc->irq;
1033 
1034 			/*
1035 			 * We call the child to parent translation function
1036 			 * only to check if the child IRQ is valid or not.
1037 			 * Just pick the rising edge type here as that is what
1038 			 * we likely need to support.
1039 			 */
1040 			ret = girq->child_to_parent_hwirq(gc, i,
1041 							  IRQ_TYPE_EDGE_RISING,
1042 							  &parent_hwirq,
1043 							  &parent_type);
1044 			if (ret) {
1045 				chip_err(gc, "skip set-up on hwirq %d\n",
1046 					 i);
1047 				continue;
1048 			}
1049 
1050 			fwspec.fwnode = gc->irq.fwnode;
1051 			/* This is the hwirq for the GPIO line side of things */
1052 			fwspec.param[0] = girq->child_offset_to_irq(gc, i);
1053 			/* Just pick something */
1054 			fwspec.param[1] = IRQ_TYPE_EDGE_RISING;
1055 			fwspec.param_count = 2;
1056 			ret = __irq_domain_alloc_irqs(gc->irq.domain,
1057 						      /* just pick something */
1058 						      -1,
1059 						      1,
1060 						      NUMA_NO_NODE,
1061 						      &fwspec,
1062 						      false,
1063 						      NULL);
1064 			if (ret < 0) {
1065 				chip_err(gc,
1066 					 "can not allocate irq for GPIO line %d parent hwirq %d in hierarchy domain: %d\n",
1067 					 i, parent_hwirq,
1068 					 ret);
1069 			}
1070 		}
1071 	}
1072 
1073 	chip_err(gc, "%s unknown fwnode type proceed anyway\n", __func__);
1074 
1075 	return;
1076 }
1077 
1078 static int gpiochip_hierarchy_irq_domain_translate(struct irq_domain *d,
1079 						   struct irq_fwspec *fwspec,
1080 						   unsigned long *hwirq,
1081 						   unsigned int *type)
1082 {
1083 	/* We support standard DT translation */
1084 	if (is_of_node(fwspec->fwnode) && fwspec->param_count == 2) {
1085 		return irq_domain_translate_twocell(d, fwspec, hwirq, type);
1086 	}
1087 
1088 	/* This is for board files and others not using DT */
1089 	if (is_fwnode_irqchip(fwspec->fwnode)) {
1090 		int ret;
1091 
1092 		ret = irq_domain_translate_twocell(d, fwspec, hwirq, type);
1093 		if (ret)
1094 			return ret;
1095 		WARN_ON(*type == IRQ_TYPE_NONE);
1096 		return 0;
1097 	}
1098 	return -EINVAL;
1099 }
1100 
1101 static int gpiochip_hierarchy_irq_domain_alloc(struct irq_domain *d,
1102 					       unsigned int irq,
1103 					       unsigned int nr_irqs,
1104 					       void *data)
1105 {
1106 	struct gpio_chip *gc = d->host_data;
1107 	irq_hw_number_t hwirq;
1108 	unsigned int type = IRQ_TYPE_NONE;
1109 	struct irq_fwspec *fwspec = data;
1110 	void *parent_arg;
1111 	unsigned int parent_hwirq;
1112 	unsigned int parent_type;
1113 	struct gpio_irq_chip *girq = &gc->irq;
1114 	int ret;
1115 
1116 	/*
1117 	 * The nr_irqs parameter is always one except for PCI multi-MSI
1118 	 * so this should not happen.
1119 	 */
1120 	WARN_ON(nr_irqs != 1);
1121 
1122 	ret = gc->irq.child_irq_domain_ops.translate(d, fwspec, &hwirq, &type);
1123 	if (ret)
1124 		return ret;
1125 
1126 	chip_dbg(gc, "allocate IRQ %d, hwirq %lu\n", irq,  hwirq);
1127 
1128 	ret = girq->child_to_parent_hwirq(gc, hwirq, type,
1129 					  &parent_hwirq, &parent_type);
1130 	if (ret) {
1131 		chip_err(gc, "can't look up hwirq %lu\n", hwirq);
1132 		return ret;
1133 	}
1134 	chip_dbg(gc, "found parent hwirq %u\n", parent_hwirq);
1135 
1136 	/*
1137 	 * We set handle_bad_irq because the .set_type() should
1138 	 * always be invoked and set the right type of handler.
1139 	 */
1140 	irq_domain_set_info(d,
1141 			    irq,
1142 			    hwirq,
1143 			    gc->irq.chip,
1144 			    gc,
1145 			    girq->handler,
1146 			    NULL, NULL);
1147 	irq_set_probe(irq);
1148 
1149 	/* This parent only handles asserted level IRQs */
1150 	parent_arg = girq->populate_parent_alloc_arg(gc, parent_hwirq, parent_type);
1151 	if (!parent_arg)
1152 		return -ENOMEM;
1153 
1154 	chip_dbg(gc, "alloc_irqs_parent for %d parent hwirq %d\n",
1155 		  irq, parent_hwirq);
1156 	irq_set_lockdep_class(irq, gc->irq.lock_key, gc->irq.request_key);
1157 	ret = irq_domain_alloc_irqs_parent(d, irq, 1, parent_arg);
1158 	/*
1159 	 * If the parent irqdomain is msi, the interrupts have already
1160 	 * been allocated, so the EEXIST is good.
1161 	 */
1162 	if (irq_domain_is_msi(d->parent) && (ret == -EEXIST))
1163 		ret = 0;
1164 	if (ret)
1165 		chip_err(gc,
1166 			 "failed to allocate parent hwirq %d for hwirq %lu\n",
1167 			 parent_hwirq, hwirq);
1168 
1169 	kfree(parent_arg);
1170 	return ret;
1171 }
1172 
1173 static unsigned int gpiochip_child_offset_to_irq_noop(struct gpio_chip *gc,
1174 						      unsigned int offset)
1175 {
1176 	return offset;
1177 }
1178 
1179 static void gpiochip_hierarchy_setup_domain_ops(struct irq_domain_ops *ops)
1180 {
1181 	ops->activate = gpiochip_irq_domain_activate;
1182 	ops->deactivate = gpiochip_irq_domain_deactivate;
1183 	ops->alloc = gpiochip_hierarchy_irq_domain_alloc;
1184 	ops->free = irq_domain_free_irqs_common;
1185 
1186 	/*
1187 	 * We only allow overriding the translate() function for
1188 	 * hierarchical chips, and this should only be done if the user
1189 	 * really need something other than 1:1 translation.
1190 	 */
1191 	if (!ops->translate)
1192 		ops->translate = gpiochip_hierarchy_irq_domain_translate;
1193 }
1194 
1195 static int gpiochip_hierarchy_add_domain(struct gpio_chip *gc)
1196 {
1197 	if (!gc->irq.child_to_parent_hwirq ||
1198 	    !gc->irq.fwnode) {
1199 		chip_err(gc, "missing irqdomain vital data\n");
1200 		return -EINVAL;
1201 	}
1202 
1203 	if (!gc->irq.child_offset_to_irq)
1204 		gc->irq.child_offset_to_irq = gpiochip_child_offset_to_irq_noop;
1205 
1206 	if (!gc->irq.populate_parent_alloc_arg)
1207 		gc->irq.populate_parent_alloc_arg =
1208 			gpiochip_populate_parent_fwspec_twocell;
1209 
1210 	gpiochip_hierarchy_setup_domain_ops(&gc->irq.child_irq_domain_ops);
1211 
1212 	gc->irq.domain = irq_domain_create_hierarchy(
1213 		gc->irq.parent_domain,
1214 		0,
1215 		gc->ngpio,
1216 		gc->irq.fwnode,
1217 		&gc->irq.child_irq_domain_ops,
1218 		gc);
1219 
1220 	if (!gc->irq.domain)
1221 		return -ENOMEM;
1222 
1223 	gpiochip_set_hierarchical_irqchip(gc, gc->irq.chip);
1224 
1225 	return 0;
1226 }
1227 
1228 static bool gpiochip_hierarchy_is_hierarchical(struct gpio_chip *gc)
1229 {
1230 	return !!gc->irq.parent_domain;
1231 }
1232 
1233 void *gpiochip_populate_parent_fwspec_twocell(struct gpio_chip *gc,
1234 					     unsigned int parent_hwirq,
1235 					     unsigned int parent_type)
1236 {
1237 	struct irq_fwspec *fwspec;
1238 
1239 	fwspec = kmalloc(sizeof(*fwspec), GFP_KERNEL);
1240 	if (!fwspec)
1241 		return NULL;
1242 
1243 	fwspec->fwnode = gc->irq.parent_domain->fwnode;
1244 	fwspec->param_count = 2;
1245 	fwspec->param[0] = parent_hwirq;
1246 	fwspec->param[1] = parent_type;
1247 
1248 	return fwspec;
1249 }
1250 EXPORT_SYMBOL_GPL(gpiochip_populate_parent_fwspec_twocell);
1251 
1252 void *gpiochip_populate_parent_fwspec_fourcell(struct gpio_chip *gc,
1253 					      unsigned int parent_hwirq,
1254 					      unsigned int parent_type)
1255 {
1256 	struct irq_fwspec *fwspec;
1257 
1258 	fwspec = kmalloc(sizeof(*fwspec), GFP_KERNEL);
1259 	if (!fwspec)
1260 		return NULL;
1261 
1262 	fwspec->fwnode = gc->irq.parent_domain->fwnode;
1263 	fwspec->param_count = 4;
1264 	fwspec->param[0] = 0;
1265 	fwspec->param[1] = parent_hwirq;
1266 	fwspec->param[2] = 0;
1267 	fwspec->param[3] = parent_type;
1268 
1269 	return fwspec;
1270 }
1271 EXPORT_SYMBOL_GPL(gpiochip_populate_parent_fwspec_fourcell);
1272 
1273 #else
1274 
1275 static int gpiochip_hierarchy_add_domain(struct gpio_chip *gc)
1276 {
1277 	return -EINVAL;
1278 }
1279 
1280 static bool gpiochip_hierarchy_is_hierarchical(struct gpio_chip *gc)
1281 {
1282 	return false;
1283 }
1284 
1285 #endif /* CONFIG_IRQ_DOMAIN_HIERARCHY */
1286 
1287 /**
1288  * gpiochip_irq_map() - maps an IRQ into a GPIO irqchip
1289  * @d: the irqdomain used by this irqchip
1290  * @irq: the global irq number used by this GPIO irqchip irq
1291  * @hwirq: the local IRQ/GPIO line offset on this gpiochip
1292  *
1293  * This function will set up the mapping for a certain IRQ line on a
1294  * gpiochip by assigning the gpiochip as chip data, and using the irqchip
1295  * stored inside the gpiochip.
1296  */
1297 int gpiochip_irq_map(struct irq_domain *d, unsigned int irq,
1298 		     irq_hw_number_t hwirq)
1299 {
1300 	struct gpio_chip *gc = d->host_data;
1301 	int ret = 0;
1302 
1303 	if (!gpiochip_irqchip_irq_valid(gc, hwirq))
1304 		return -ENXIO;
1305 
1306 	irq_set_chip_data(irq, gc);
1307 	/*
1308 	 * This lock class tells lockdep that GPIO irqs are in a different
1309 	 * category than their parents, so it won't report false recursion.
1310 	 */
1311 	irq_set_lockdep_class(irq, gc->irq.lock_key, gc->irq.request_key);
1312 	irq_set_chip_and_handler(irq, gc->irq.chip, gc->irq.handler);
1313 	/* Chips that use nested thread handlers have them marked */
1314 	if (gc->irq.threaded)
1315 		irq_set_nested_thread(irq, 1);
1316 	irq_set_noprobe(irq);
1317 
1318 	if (gc->irq.num_parents == 1)
1319 		ret = irq_set_parent(irq, gc->irq.parents[0]);
1320 	else if (gc->irq.map)
1321 		ret = irq_set_parent(irq, gc->irq.map[hwirq]);
1322 
1323 	if (ret < 0)
1324 		return ret;
1325 
1326 	/*
1327 	 * No set-up of the hardware will happen if IRQ_TYPE_NONE
1328 	 * is passed as default type.
1329 	 */
1330 	if (gc->irq.default_type != IRQ_TYPE_NONE)
1331 		irq_set_irq_type(irq, gc->irq.default_type);
1332 
1333 	return 0;
1334 }
1335 EXPORT_SYMBOL_GPL(gpiochip_irq_map);
1336 
1337 void gpiochip_irq_unmap(struct irq_domain *d, unsigned int irq)
1338 {
1339 	struct gpio_chip *gc = d->host_data;
1340 
1341 	if (gc->irq.threaded)
1342 		irq_set_nested_thread(irq, 0);
1343 	irq_set_chip_and_handler(irq, NULL, NULL);
1344 	irq_set_chip_data(irq, NULL);
1345 }
1346 EXPORT_SYMBOL_GPL(gpiochip_irq_unmap);
1347 
1348 static const struct irq_domain_ops gpiochip_domain_ops = {
1349 	.map	= gpiochip_irq_map,
1350 	.unmap	= gpiochip_irq_unmap,
1351 	/* Virtually all GPIO irqchips are twocell:ed */
1352 	.xlate	= irq_domain_xlate_twocell,
1353 };
1354 
1355 /*
1356  * TODO: move these activate/deactivate in under the hierarchicial
1357  * irqchip implementation as static once SPMI and SSBI (all external
1358  * users) are phased over.
1359  */
1360 /**
1361  * gpiochip_irq_domain_activate() - Lock a GPIO to be used as an IRQ
1362  * @domain: The IRQ domain used by this IRQ chip
1363  * @data: Outermost irq_data associated with the IRQ
1364  * @reserve: If set, only reserve an interrupt vector instead of assigning one
1365  *
1366  * This function is a wrapper that calls gpiochip_lock_as_irq() and is to be
1367  * used as the activate function for the &struct irq_domain_ops. The host_data
1368  * for the IRQ domain must be the &struct gpio_chip.
1369  */
1370 int gpiochip_irq_domain_activate(struct irq_domain *domain,
1371 				 struct irq_data *data, bool reserve)
1372 {
1373 	struct gpio_chip *gc = domain->host_data;
1374 
1375 	return gpiochip_lock_as_irq(gc, data->hwirq);
1376 }
1377 EXPORT_SYMBOL_GPL(gpiochip_irq_domain_activate);
1378 
1379 /**
1380  * gpiochip_irq_domain_deactivate() - Unlock a GPIO used as an IRQ
1381  * @domain: The IRQ domain used by this IRQ chip
1382  * @data: Outermost irq_data associated with the IRQ
1383  *
1384  * This function is a wrapper that will call gpiochip_unlock_as_irq() and is to
1385  * be used as the deactivate function for the &struct irq_domain_ops. The
1386  * host_data for the IRQ domain must be the &struct gpio_chip.
1387  */
1388 void gpiochip_irq_domain_deactivate(struct irq_domain *domain,
1389 				    struct irq_data *data)
1390 {
1391 	struct gpio_chip *gc = domain->host_data;
1392 
1393 	return gpiochip_unlock_as_irq(gc, data->hwirq);
1394 }
1395 EXPORT_SYMBOL_GPL(gpiochip_irq_domain_deactivate);
1396 
1397 static int gpiochip_to_irq(struct gpio_chip *gc, unsigned offset)
1398 {
1399 	struct irq_domain *domain = gc->irq.domain;
1400 
1401 	if (!gpiochip_irqchip_irq_valid(gc, offset))
1402 		return -ENXIO;
1403 
1404 #ifdef CONFIG_IRQ_DOMAIN_HIERARCHY
1405 	if (irq_domain_is_hierarchy(domain)) {
1406 		struct irq_fwspec spec;
1407 
1408 		spec.fwnode = domain->fwnode;
1409 		spec.param_count = 2;
1410 		spec.param[0] = gc->irq.child_offset_to_irq(gc, offset);
1411 		spec.param[1] = IRQ_TYPE_NONE;
1412 
1413 		return irq_create_fwspec_mapping(&spec);
1414 	}
1415 #endif
1416 
1417 	return irq_create_mapping(domain, offset);
1418 }
1419 
1420 static int gpiochip_irq_reqres(struct irq_data *d)
1421 {
1422 	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
1423 
1424 	return gpiochip_reqres_irq(gc, d->hwirq);
1425 }
1426 
1427 static void gpiochip_irq_relres(struct irq_data *d)
1428 {
1429 	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
1430 
1431 	gpiochip_relres_irq(gc, d->hwirq);
1432 }
1433 
1434 static void gpiochip_irq_mask(struct irq_data *d)
1435 {
1436 	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
1437 
1438 	if (gc->irq.irq_mask)
1439 		gc->irq.irq_mask(d);
1440 	gpiochip_disable_irq(gc, d->hwirq);
1441 }
1442 
1443 static void gpiochip_irq_unmask(struct irq_data *d)
1444 {
1445 	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
1446 
1447 	gpiochip_enable_irq(gc, d->hwirq);
1448 	if (gc->irq.irq_unmask)
1449 		gc->irq.irq_unmask(d);
1450 }
1451 
1452 static void gpiochip_irq_enable(struct irq_data *d)
1453 {
1454 	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
1455 
1456 	gpiochip_enable_irq(gc, d->hwirq);
1457 	gc->irq.irq_enable(d);
1458 }
1459 
1460 static void gpiochip_irq_disable(struct irq_data *d)
1461 {
1462 	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
1463 
1464 	gc->irq.irq_disable(d);
1465 	gpiochip_disable_irq(gc, d->hwirq);
1466 }
1467 
1468 static void gpiochip_set_irq_hooks(struct gpio_chip *gc)
1469 {
1470 	struct irq_chip *irqchip = gc->irq.chip;
1471 
1472 	if (!irqchip->irq_request_resources &&
1473 	    !irqchip->irq_release_resources) {
1474 		irqchip->irq_request_resources = gpiochip_irq_reqres;
1475 		irqchip->irq_release_resources = gpiochip_irq_relres;
1476 	}
1477 	if (WARN_ON(gc->irq.irq_enable))
1478 		return;
1479 	/* Check if the irqchip already has this hook... */
1480 	if (irqchip->irq_enable == gpiochip_irq_enable) {
1481 		/*
1482 		 * ...and if so, give a gentle warning that this is bad
1483 		 * practice.
1484 		 */
1485 		chip_info(gc,
1486 			  "detected irqchip that is shared with multiple gpiochips: please fix the driver.\n");
1487 		return;
1488 	}
1489 
1490 	if (irqchip->irq_disable) {
1491 		gc->irq.irq_disable = irqchip->irq_disable;
1492 		irqchip->irq_disable = gpiochip_irq_disable;
1493 	} else {
1494 		gc->irq.irq_mask = irqchip->irq_mask;
1495 		irqchip->irq_mask = gpiochip_irq_mask;
1496 	}
1497 
1498 	if (irqchip->irq_enable) {
1499 		gc->irq.irq_enable = irqchip->irq_enable;
1500 		irqchip->irq_enable = gpiochip_irq_enable;
1501 	} else {
1502 		gc->irq.irq_unmask = irqchip->irq_unmask;
1503 		irqchip->irq_unmask = gpiochip_irq_unmask;
1504 	}
1505 }
1506 
1507 /**
1508  * gpiochip_add_irqchip() - adds an IRQ chip to a GPIO chip
1509  * @gc: the GPIO chip to add the IRQ chip to
1510  * @lock_key: lockdep class for IRQ lock
1511  * @request_key: lockdep class for IRQ request
1512  */
1513 static int gpiochip_add_irqchip(struct gpio_chip *gc,
1514 				struct lock_class_key *lock_key,
1515 				struct lock_class_key *request_key)
1516 {
1517 	struct irq_chip *irqchip = gc->irq.chip;
1518 	const struct irq_domain_ops *ops = NULL;
1519 	struct device_node *np;
1520 	unsigned int type;
1521 	unsigned int i;
1522 
1523 	if (!irqchip)
1524 		return 0;
1525 
1526 	if (gc->irq.parent_handler && gc->can_sleep) {
1527 		chip_err(gc, "you cannot have chained interrupts on a chip that may sleep\n");
1528 		return -EINVAL;
1529 	}
1530 
1531 	np = gc->gpiodev->dev.of_node;
1532 	type = gc->irq.default_type;
1533 
1534 	/*
1535 	 * Specifying a default trigger is a terrible idea if DT or ACPI is
1536 	 * used to configure the interrupts, as you may end up with
1537 	 * conflicting triggers. Tell the user, and reset to NONE.
1538 	 */
1539 	if (WARN(np && type != IRQ_TYPE_NONE,
1540 		 "%s: Ignoring %u default trigger\n", np->full_name, type))
1541 		type = IRQ_TYPE_NONE;
1542 
1543 	if (has_acpi_companion(gc->parent) && type != IRQ_TYPE_NONE) {
1544 		acpi_handle_warn(ACPI_HANDLE(gc->parent),
1545 				 "Ignoring %u default trigger\n", type);
1546 		type = IRQ_TYPE_NONE;
1547 	}
1548 
1549 	gc->to_irq = gpiochip_to_irq;
1550 	gc->irq.default_type = type;
1551 	gc->irq.lock_key = lock_key;
1552 	gc->irq.request_key = request_key;
1553 
1554 	/* If a parent irqdomain is provided, let's build a hierarchy */
1555 	if (gpiochip_hierarchy_is_hierarchical(gc)) {
1556 		int ret = gpiochip_hierarchy_add_domain(gc);
1557 		if (ret)
1558 			return ret;
1559 	} else {
1560 		/* Some drivers provide custom irqdomain ops */
1561 		if (gc->irq.domain_ops)
1562 			ops = gc->irq.domain_ops;
1563 
1564 		if (!ops)
1565 			ops = &gpiochip_domain_ops;
1566 		gc->irq.domain = irq_domain_add_simple(np,
1567 			gc->ngpio,
1568 			gc->irq.first,
1569 			ops, gc);
1570 		if (!gc->irq.domain)
1571 			return -EINVAL;
1572 	}
1573 
1574 	if (gc->irq.parent_handler) {
1575 		void *data = gc->irq.parent_handler_data ?: gc;
1576 
1577 		for (i = 0; i < gc->irq.num_parents; i++) {
1578 			/*
1579 			 * The parent IRQ chip is already using the chip_data
1580 			 * for this IRQ chip, so our callbacks simply use the
1581 			 * handler_data.
1582 			 */
1583 			irq_set_chained_handler_and_data(gc->irq.parents[i],
1584 							 gc->irq.parent_handler,
1585 							 data);
1586 		}
1587 	}
1588 
1589 	gpiochip_set_irq_hooks(gc);
1590 
1591 	acpi_gpiochip_request_interrupts(gc);
1592 
1593 	return 0;
1594 }
1595 
1596 /**
1597  * gpiochip_irqchip_remove() - removes an irqchip added to a gpiochip
1598  * @gc: the gpiochip to remove the irqchip from
1599  *
1600  * This is called only from gpiochip_remove()
1601  */
1602 static void gpiochip_irqchip_remove(struct gpio_chip *gc)
1603 {
1604 	struct irq_chip *irqchip = gc->irq.chip;
1605 	unsigned int offset;
1606 
1607 	acpi_gpiochip_free_interrupts(gc);
1608 
1609 	if (irqchip && gc->irq.parent_handler) {
1610 		struct gpio_irq_chip *irq = &gc->irq;
1611 		unsigned int i;
1612 
1613 		for (i = 0; i < irq->num_parents; i++)
1614 			irq_set_chained_handler_and_data(irq->parents[i],
1615 							 NULL, NULL);
1616 	}
1617 
1618 	/* Remove all IRQ mappings and delete the domain */
1619 	if (gc->irq.domain) {
1620 		unsigned int irq;
1621 
1622 		for (offset = 0; offset < gc->ngpio; offset++) {
1623 			if (!gpiochip_irqchip_irq_valid(gc, offset))
1624 				continue;
1625 
1626 			irq = irq_find_mapping(gc->irq.domain, offset);
1627 			irq_dispose_mapping(irq);
1628 		}
1629 
1630 		irq_domain_remove(gc->irq.domain);
1631 	}
1632 
1633 	if (irqchip) {
1634 		if (irqchip->irq_request_resources == gpiochip_irq_reqres) {
1635 			irqchip->irq_request_resources = NULL;
1636 			irqchip->irq_release_resources = NULL;
1637 		}
1638 		if (irqchip->irq_enable == gpiochip_irq_enable) {
1639 			irqchip->irq_enable = gc->irq.irq_enable;
1640 			irqchip->irq_disable = gc->irq.irq_disable;
1641 		}
1642 	}
1643 	gc->irq.irq_enable = NULL;
1644 	gc->irq.irq_disable = NULL;
1645 	gc->irq.chip = NULL;
1646 
1647 	gpiochip_irqchip_free_valid_mask(gc);
1648 }
1649 
1650 /**
1651  * gpiochip_irqchip_add_key() - adds an irqchip to a gpiochip
1652  * @gc: the gpiochip to add the irqchip to
1653  * @irqchip: the irqchip to add to the gpiochip
1654  * @first_irq: if not dynamically assigned, the base (first) IRQ to
1655  * allocate gpiochip irqs from
1656  * @handler: the irq handler to use (often a predefined irq core function)
1657  * @type: the default type for IRQs on this irqchip, pass IRQ_TYPE_NONE
1658  * to have the core avoid setting up any default type in the hardware.
1659  * @threaded: whether this irqchip uses a nested thread handler
1660  * @lock_key: lockdep class for IRQ lock
1661  * @request_key: lockdep class for IRQ request
1662  *
1663  * This function closely associates a certain irqchip with a certain
1664  * gpiochip, providing an irq domain to translate the local IRQs to
1665  * global irqs in the gpiolib core, and making sure that the gpiochip
1666  * is passed as chip data to all related functions. Driver callbacks
1667  * need to use gpiochip_get_data() to get their local state containers back
1668  * from the gpiochip passed as chip data. An irqdomain will be stored
1669  * in the gpiochip that shall be used by the driver to handle IRQ number
1670  * translation. The gpiochip will need to be initialized and registered
1671  * before calling this function.
1672  *
1673  * This function will handle two cell:ed simple IRQs and assumes all
1674  * the pins on the gpiochip can generate a unique IRQ. Everything else
1675  * need to be open coded.
1676  */
1677 int gpiochip_irqchip_add_key(struct gpio_chip *gc,
1678 			     struct irq_chip *irqchip,
1679 			     unsigned int first_irq,
1680 			     irq_flow_handler_t handler,
1681 			     unsigned int type,
1682 			     bool threaded,
1683 			     struct lock_class_key *lock_key,
1684 			     struct lock_class_key *request_key)
1685 {
1686 	struct device_node *of_node;
1687 
1688 	if (!gc || !irqchip)
1689 		return -EINVAL;
1690 
1691 	if (!gc->parent) {
1692 		chip_err(gc, "missing gpiochip .dev parent pointer\n");
1693 		return -EINVAL;
1694 	}
1695 	gc->irq.threaded = threaded;
1696 	of_node = gc->parent->of_node;
1697 #ifdef CONFIG_OF_GPIO
1698 	/*
1699 	 * If the gpiochip has an assigned OF node this takes precedence
1700 	 * FIXME: get rid of this and use gc->parent->of_node
1701 	 * everywhere
1702 	 */
1703 	if (gc->of_node)
1704 		of_node = gc->of_node;
1705 #endif
1706 	/*
1707 	 * Specifying a default trigger is a terrible idea if DT or ACPI is
1708 	 * used to configure the interrupts, as you may end-up with
1709 	 * conflicting triggers. Tell the user, and reset to NONE.
1710 	 */
1711 	if (WARN(of_node && type != IRQ_TYPE_NONE,
1712 		 "%pOF: Ignoring %d default trigger\n", of_node, type))
1713 		type = IRQ_TYPE_NONE;
1714 	if (has_acpi_companion(gc->parent) && type != IRQ_TYPE_NONE) {
1715 		acpi_handle_warn(ACPI_HANDLE(gc->parent),
1716 				 "Ignoring %d default trigger\n", type);
1717 		type = IRQ_TYPE_NONE;
1718 	}
1719 
1720 	gc->irq.chip = irqchip;
1721 	gc->irq.handler = handler;
1722 	gc->irq.default_type = type;
1723 	gc->to_irq = gpiochip_to_irq;
1724 	gc->irq.lock_key = lock_key;
1725 	gc->irq.request_key = request_key;
1726 	gc->irq.domain = irq_domain_add_simple(of_node,
1727 					gc->ngpio, first_irq,
1728 					&gpiochip_domain_ops, gc);
1729 	if (!gc->irq.domain) {
1730 		gc->irq.chip = NULL;
1731 		return -EINVAL;
1732 	}
1733 
1734 	gpiochip_set_irq_hooks(gc);
1735 
1736 	acpi_gpiochip_request_interrupts(gc);
1737 
1738 	return 0;
1739 }
1740 EXPORT_SYMBOL_GPL(gpiochip_irqchip_add_key);
1741 
1742 /**
1743  * gpiochip_irqchip_add_domain() - adds an irqdomain to a gpiochip
1744  * @gc: the gpiochip to add the irqchip to
1745  * @domain: the irqdomain to add to the gpiochip
1746  *
1747  * This function adds an IRQ domain to the gpiochip.
1748  */
1749 int gpiochip_irqchip_add_domain(struct gpio_chip *gc,
1750 				struct irq_domain *domain)
1751 {
1752 	if (!domain)
1753 		return -EINVAL;
1754 
1755 	gc->to_irq = gpiochip_to_irq;
1756 	gc->irq.domain = domain;
1757 
1758 	return 0;
1759 }
1760 EXPORT_SYMBOL_GPL(gpiochip_irqchip_add_domain);
1761 
1762 #else /* CONFIG_GPIOLIB_IRQCHIP */
1763 
1764 static inline int gpiochip_add_irqchip(struct gpio_chip *gc,
1765 				       struct lock_class_key *lock_key,
1766 				       struct lock_class_key *request_key)
1767 {
1768 	return 0;
1769 }
1770 static void gpiochip_irqchip_remove(struct gpio_chip *gc) {}
1771 
1772 static inline int gpiochip_irqchip_init_hw(struct gpio_chip *gc)
1773 {
1774 	return 0;
1775 }
1776 
1777 static inline int gpiochip_irqchip_init_valid_mask(struct gpio_chip *gc)
1778 {
1779 	return 0;
1780 }
1781 static inline void gpiochip_irqchip_free_valid_mask(struct gpio_chip *gc)
1782 { }
1783 
1784 #endif /* CONFIG_GPIOLIB_IRQCHIP */
1785 
1786 /**
1787  * gpiochip_generic_request() - request the gpio function for a pin
1788  * @gc: the gpiochip owning the GPIO
1789  * @offset: the offset of the GPIO to request for GPIO function
1790  */
1791 int gpiochip_generic_request(struct gpio_chip *gc, unsigned offset)
1792 {
1793 #ifdef CONFIG_PINCTRL
1794 	if (list_empty(&gc->gpiodev->pin_ranges))
1795 		return 0;
1796 #endif
1797 
1798 	return pinctrl_gpio_request(gc->gpiodev->base + offset);
1799 }
1800 EXPORT_SYMBOL_GPL(gpiochip_generic_request);
1801 
1802 /**
1803  * gpiochip_generic_free() - free the gpio function from a pin
1804  * @gc: the gpiochip to request the gpio function for
1805  * @offset: the offset of the GPIO to free from GPIO function
1806  */
1807 void gpiochip_generic_free(struct gpio_chip *gc, unsigned offset)
1808 {
1809 #ifdef CONFIG_PINCTRL
1810 	if (list_empty(&gc->gpiodev->pin_ranges))
1811 		return;
1812 #endif
1813 
1814 	pinctrl_gpio_free(gc->gpiodev->base + offset);
1815 }
1816 EXPORT_SYMBOL_GPL(gpiochip_generic_free);
1817 
1818 /**
1819  * gpiochip_generic_config() - apply configuration for a pin
1820  * @gc: the gpiochip owning the GPIO
1821  * @offset: the offset of the GPIO to apply the configuration
1822  * @config: the configuration to be applied
1823  */
1824 int gpiochip_generic_config(struct gpio_chip *gc, unsigned offset,
1825 			    unsigned long config)
1826 {
1827 	return pinctrl_gpio_set_config(gc->gpiodev->base + offset, config);
1828 }
1829 EXPORT_SYMBOL_GPL(gpiochip_generic_config);
1830 
1831 #ifdef CONFIG_PINCTRL
1832 
1833 /**
1834  * gpiochip_add_pingroup_range() - add a range for GPIO <-> pin mapping
1835  * @gc: the gpiochip to add the range for
1836  * @pctldev: the pin controller to map to
1837  * @gpio_offset: the start offset in the current gpio_chip number space
1838  * @pin_group: name of the pin group inside the pin controller
1839  *
1840  * Calling this function directly from a DeviceTree-supported
1841  * pinctrl driver is DEPRECATED. Please see Section 2.1 of
1842  * Documentation/devicetree/bindings/gpio/gpio.txt on how to
1843  * bind pinctrl and gpio drivers via the "gpio-ranges" property.
1844  */
1845 int gpiochip_add_pingroup_range(struct gpio_chip *gc,
1846 			struct pinctrl_dev *pctldev,
1847 			unsigned int gpio_offset, const char *pin_group)
1848 {
1849 	struct gpio_pin_range *pin_range;
1850 	struct gpio_device *gdev = gc->gpiodev;
1851 	int ret;
1852 
1853 	pin_range = kzalloc(sizeof(*pin_range), GFP_KERNEL);
1854 	if (!pin_range) {
1855 		chip_err(gc, "failed to allocate pin ranges\n");
1856 		return -ENOMEM;
1857 	}
1858 
1859 	/* Use local offset as range ID */
1860 	pin_range->range.id = gpio_offset;
1861 	pin_range->range.gc = gc;
1862 	pin_range->range.name = gc->label;
1863 	pin_range->range.base = gdev->base + gpio_offset;
1864 	pin_range->pctldev = pctldev;
1865 
1866 	ret = pinctrl_get_group_pins(pctldev, pin_group,
1867 					&pin_range->range.pins,
1868 					&pin_range->range.npins);
1869 	if (ret < 0) {
1870 		kfree(pin_range);
1871 		return ret;
1872 	}
1873 
1874 	pinctrl_add_gpio_range(pctldev, &pin_range->range);
1875 
1876 	chip_dbg(gc, "created GPIO range %d->%d ==> %s PINGRP %s\n",
1877 		 gpio_offset, gpio_offset + pin_range->range.npins - 1,
1878 		 pinctrl_dev_get_devname(pctldev), pin_group);
1879 
1880 	list_add_tail(&pin_range->node, &gdev->pin_ranges);
1881 
1882 	return 0;
1883 }
1884 EXPORT_SYMBOL_GPL(gpiochip_add_pingroup_range);
1885 
1886 /**
1887  * gpiochip_add_pin_range() - add a range for GPIO <-> pin mapping
1888  * @gc: the gpiochip to add the range for
1889  * @pinctl_name: the dev_name() of the pin controller to map to
1890  * @gpio_offset: the start offset in the current gpio_chip number space
1891  * @pin_offset: the start offset in the pin controller number space
1892  * @npins: the number of pins from the offset of each pin space (GPIO and
1893  *	pin controller) to accumulate in this range
1894  *
1895  * Returns:
1896  * 0 on success, or a negative error-code on failure.
1897  *
1898  * Calling this function directly from a DeviceTree-supported
1899  * pinctrl driver is DEPRECATED. Please see Section 2.1 of
1900  * Documentation/devicetree/bindings/gpio/gpio.txt on how to
1901  * bind pinctrl and gpio drivers via the "gpio-ranges" property.
1902  */
1903 int gpiochip_add_pin_range(struct gpio_chip *gc, const char *pinctl_name,
1904 			   unsigned int gpio_offset, unsigned int pin_offset,
1905 			   unsigned int npins)
1906 {
1907 	struct gpio_pin_range *pin_range;
1908 	struct gpio_device *gdev = gc->gpiodev;
1909 	int ret;
1910 
1911 	pin_range = kzalloc(sizeof(*pin_range), GFP_KERNEL);
1912 	if (!pin_range) {
1913 		chip_err(gc, "failed to allocate pin ranges\n");
1914 		return -ENOMEM;
1915 	}
1916 
1917 	/* Use local offset as range ID */
1918 	pin_range->range.id = gpio_offset;
1919 	pin_range->range.gc = gc;
1920 	pin_range->range.name = gc->label;
1921 	pin_range->range.base = gdev->base + gpio_offset;
1922 	pin_range->range.pin_base = pin_offset;
1923 	pin_range->range.npins = npins;
1924 	pin_range->pctldev = pinctrl_find_and_add_gpio_range(pinctl_name,
1925 			&pin_range->range);
1926 	if (IS_ERR(pin_range->pctldev)) {
1927 		ret = PTR_ERR(pin_range->pctldev);
1928 		chip_err(gc, "could not create pin range\n");
1929 		kfree(pin_range);
1930 		return ret;
1931 	}
1932 	chip_dbg(gc, "created GPIO range %d->%d ==> %s PIN %d->%d\n",
1933 		 gpio_offset, gpio_offset + npins - 1,
1934 		 pinctl_name,
1935 		 pin_offset, pin_offset + npins - 1);
1936 
1937 	list_add_tail(&pin_range->node, &gdev->pin_ranges);
1938 
1939 	return 0;
1940 }
1941 EXPORT_SYMBOL_GPL(gpiochip_add_pin_range);
1942 
1943 /**
1944  * gpiochip_remove_pin_ranges() - remove all the GPIO <-> pin mappings
1945  * @gc: the chip to remove all the mappings for
1946  */
1947 void gpiochip_remove_pin_ranges(struct gpio_chip *gc)
1948 {
1949 	struct gpio_pin_range *pin_range, *tmp;
1950 	struct gpio_device *gdev = gc->gpiodev;
1951 
1952 	list_for_each_entry_safe(pin_range, tmp, &gdev->pin_ranges, node) {
1953 		list_del(&pin_range->node);
1954 		pinctrl_remove_gpio_range(pin_range->pctldev,
1955 				&pin_range->range);
1956 		kfree(pin_range);
1957 	}
1958 }
1959 EXPORT_SYMBOL_GPL(gpiochip_remove_pin_ranges);
1960 
1961 #endif /* CONFIG_PINCTRL */
1962 
1963 /* These "optional" allocation calls help prevent drivers from stomping
1964  * on each other, and help provide better diagnostics in debugfs.
1965  * They're called even less than the "set direction" calls.
1966  */
1967 static int gpiod_request_commit(struct gpio_desc *desc, const char *label)
1968 {
1969 	struct gpio_chip	*gc = desc->gdev->chip;
1970 	int			ret;
1971 	unsigned long		flags;
1972 	unsigned		offset;
1973 
1974 	if (label) {
1975 		label = kstrdup_const(label, GFP_KERNEL);
1976 		if (!label)
1977 			return -ENOMEM;
1978 	}
1979 
1980 	spin_lock_irqsave(&gpio_lock, flags);
1981 
1982 	/* NOTE:  gpio_request() can be called in early boot,
1983 	 * before IRQs are enabled, for non-sleeping (SOC) GPIOs.
1984 	 */
1985 
1986 	if (test_and_set_bit(FLAG_REQUESTED, &desc->flags) == 0) {
1987 		desc_set_label(desc, label ? : "?");
1988 		ret = 0;
1989 	} else {
1990 		kfree_const(label);
1991 		ret = -EBUSY;
1992 		goto done;
1993 	}
1994 
1995 	if (gc->request) {
1996 		/* gc->request may sleep */
1997 		spin_unlock_irqrestore(&gpio_lock, flags);
1998 		offset = gpio_chip_hwgpio(desc);
1999 		if (gpiochip_line_is_valid(gc, offset))
2000 			ret = gc->request(gc, offset);
2001 		else
2002 			ret = -EINVAL;
2003 		spin_lock_irqsave(&gpio_lock, flags);
2004 
2005 		if (ret < 0) {
2006 			desc_set_label(desc, NULL);
2007 			kfree_const(label);
2008 			clear_bit(FLAG_REQUESTED, &desc->flags);
2009 			goto done;
2010 		}
2011 	}
2012 	if (gc->get_direction) {
2013 		/* gc->get_direction may sleep */
2014 		spin_unlock_irqrestore(&gpio_lock, flags);
2015 		gpiod_get_direction(desc);
2016 		spin_lock_irqsave(&gpio_lock, flags);
2017 	}
2018 done:
2019 	spin_unlock_irqrestore(&gpio_lock, flags);
2020 	return ret;
2021 }
2022 
2023 /*
2024  * This descriptor validation needs to be inserted verbatim into each
2025  * function taking a descriptor, so we need to use a preprocessor
2026  * macro to avoid endless duplication. If the desc is NULL it is an
2027  * optional GPIO and calls should just bail out.
2028  */
2029 static int validate_desc(const struct gpio_desc *desc, const char *func)
2030 {
2031 	if (!desc)
2032 		return 0;
2033 	if (IS_ERR(desc)) {
2034 		pr_warn("%s: invalid GPIO (errorpointer)\n", func);
2035 		return PTR_ERR(desc);
2036 	}
2037 	if (!desc->gdev) {
2038 		pr_warn("%s: invalid GPIO (no device)\n", func);
2039 		return -EINVAL;
2040 	}
2041 	if (!desc->gdev->chip) {
2042 		dev_warn(&desc->gdev->dev,
2043 			 "%s: backing chip is gone\n", func);
2044 		return 0;
2045 	}
2046 	return 1;
2047 }
2048 
2049 #define VALIDATE_DESC(desc) do { \
2050 	int __valid = validate_desc(desc, __func__); \
2051 	if (__valid <= 0) \
2052 		return __valid; \
2053 	} while (0)
2054 
2055 #define VALIDATE_DESC_VOID(desc) do { \
2056 	int __valid = validate_desc(desc, __func__); \
2057 	if (__valid <= 0) \
2058 		return; \
2059 	} while (0)
2060 
2061 int gpiod_request(struct gpio_desc *desc, const char *label)
2062 {
2063 	int ret = -EPROBE_DEFER;
2064 	struct gpio_device *gdev;
2065 
2066 	VALIDATE_DESC(desc);
2067 	gdev = desc->gdev;
2068 
2069 	if (try_module_get(gdev->owner)) {
2070 		ret = gpiod_request_commit(desc, label);
2071 		if (ret < 0)
2072 			module_put(gdev->owner);
2073 		else
2074 			get_device(&gdev->dev);
2075 	}
2076 
2077 	if (ret)
2078 		gpiod_dbg(desc, "%s: status %d\n", __func__, ret);
2079 
2080 	return ret;
2081 }
2082 
2083 static bool gpiod_free_commit(struct gpio_desc *desc)
2084 {
2085 	bool			ret = false;
2086 	unsigned long		flags;
2087 	struct gpio_chip	*gc;
2088 
2089 	might_sleep();
2090 
2091 	gpiod_unexport(desc);
2092 
2093 	spin_lock_irqsave(&gpio_lock, flags);
2094 
2095 	gc = desc->gdev->chip;
2096 	if (gc && test_bit(FLAG_REQUESTED, &desc->flags)) {
2097 		if (gc->free) {
2098 			spin_unlock_irqrestore(&gpio_lock, flags);
2099 			might_sleep_if(gc->can_sleep);
2100 			gc->free(gc, gpio_chip_hwgpio(desc));
2101 			spin_lock_irqsave(&gpio_lock, flags);
2102 		}
2103 		kfree_const(desc->label);
2104 		desc_set_label(desc, NULL);
2105 		clear_bit(FLAG_ACTIVE_LOW, &desc->flags);
2106 		clear_bit(FLAG_REQUESTED, &desc->flags);
2107 		clear_bit(FLAG_OPEN_DRAIN, &desc->flags);
2108 		clear_bit(FLAG_OPEN_SOURCE, &desc->flags);
2109 		clear_bit(FLAG_PULL_UP, &desc->flags);
2110 		clear_bit(FLAG_PULL_DOWN, &desc->flags);
2111 		clear_bit(FLAG_BIAS_DISABLE, &desc->flags);
2112 		clear_bit(FLAG_EDGE_RISING, &desc->flags);
2113 		clear_bit(FLAG_EDGE_FALLING, &desc->flags);
2114 		clear_bit(FLAG_IS_HOGGED, &desc->flags);
2115 #ifdef CONFIG_OF_DYNAMIC
2116 		desc->hog = NULL;
2117 #endif
2118 #ifdef CONFIG_GPIO_CDEV
2119 		WRITE_ONCE(desc->debounce_period_us, 0);
2120 #endif
2121 		ret = true;
2122 	}
2123 
2124 	spin_unlock_irqrestore(&gpio_lock, flags);
2125 	blocking_notifier_call_chain(&desc->gdev->notifier,
2126 				     GPIOLINE_CHANGED_RELEASED, desc);
2127 
2128 	return ret;
2129 }
2130 
2131 void gpiod_free(struct gpio_desc *desc)
2132 {
2133 	if (desc && desc->gdev && gpiod_free_commit(desc)) {
2134 		module_put(desc->gdev->owner);
2135 		put_device(&desc->gdev->dev);
2136 	} else {
2137 		WARN_ON(extra_checks);
2138 	}
2139 }
2140 
2141 /**
2142  * gpiochip_is_requested - return string iff signal was requested
2143  * @gc: controller managing the signal
2144  * @offset: of signal within controller's 0..(ngpio - 1) range
2145  *
2146  * Returns NULL if the GPIO is not currently requested, else a string.
2147  * The string returned is the label passed to gpio_request(); if none has been
2148  * passed it is a meaningless, non-NULL constant.
2149  *
2150  * This function is for use by GPIO controller drivers.  The label can
2151  * help with diagnostics, and knowing that the signal is used as a GPIO
2152  * can help avoid accidentally multiplexing it to another controller.
2153  */
2154 const char *gpiochip_is_requested(struct gpio_chip *gc, unsigned offset)
2155 {
2156 	struct gpio_desc *desc;
2157 
2158 	if (offset >= gc->ngpio)
2159 		return NULL;
2160 
2161 	desc = gpiochip_get_desc(gc, offset);
2162 	if (IS_ERR(desc))
2163 		return NULL;
2164 
2165 	if (test_bit(FLAG_REQUESTED, &desc->flags) == 0)
2166 		return NULL;
2167 	return desc->label;
2168 }
2169 EXPORT_SYMBOL_GPL(gpiochip_is_requested);
2170 
2171 /**
2172  * gpiochip_request_own_desc - Allow GPIO chip to request its own descriptor
2173  * @gc: GPIO chip
2174  * @hwnum: hardware number of the GPIO for which to request the descriptor
2175  * @label: label for the GPIO
2176  * @lflags: lookup flags for this GPIO or 0 if default, this can be used to
2177  * specify things like line inversion semantics with the machine flags
2178  * such as GPIO_OUT_LOW
2179  * @dflags: descriptor request flags for this GPIO or 0 if default, this
2180  * can be used to specify consumer semantics such as open drain
2181  *
2182  * Function allows GPIO chip drivers to request and use their own GPIO
2183  * descriptors via gpiolib API. Difference to gpiod_request() is that this
2184  * function will not increase reference count of the GPIO chip module. This
2185  * allows the GPIO chip module to be unloaded as needed (we assume that the
2186  * GPIO chip driver handles freeing the GPIOs it has requested).
2187  *
2188  * Returns:
2189  * A pointer to the GPIO descriptor, or an ERR_PTR()-encoded negative error
2190  * code on failure.
2191  */
2192 struct gpio_desc *gpiochip_request_own_desc(struct gpio_chip *gc,
2193 					    unsigned int hwnum,
2194 					    const char *label,
2195 					    enum gpio_lookup_flags lflags,
2196 					    enum gpiod_flags dflags)
2197 {
2198 	struct gpio_desc *desc = gpiochip_get_desc(gc, hwnum);
2199 	int ret;
2200 
2201 	if (IS_ERR(desc)) {
2202 		chip_err(gc, "failed to get GPIO descriptor\n");
2203 		return desc;
2204 	}
2205 
2206 	ret = gpiod_request_commit(desc, label);
2207 	if (ret < 0)
2208 		return ERR_PTR(ret);
2209 
2210 	ret = gpiod_configure_flags(desc, label, lflags, dflags);
2211 	if (ret) {
2212 		chip_err(gc, "setup of own GPIO %s failed\n", label);
2213 		gpiod_free_commit(desc);
2214 		return ERR_PTR(ret);
2215 	}
2216 
2217 	return desc;
2218 }
2219 EXPORT_SYMBOL_GPL(gpiochip_request_own_desc);
2220 
2221 /**
2222  * gpiochip_free_own_desc - Free GPIO requested by the chip driver
2223  * @desc: GPIO descriptor to free
2224  *
2225  * Function frees the given GPIO requested previously with
2226  * gpiochip_request_own_desc().
2227  */
2228 void gpiochip_free_own_desc(struct gpio_desc *desc)
2229 {
2230 	if (desc)
2231 		gpiod_free_commit(desc);
2232 }
2233 EXPORT_SYMBOL_GPL(gpiochip_free_own_desc);
2234 
2235 /*
2236  * Drivers MUST set GPIO direction before making get/set calls.  In
2237  * some cases this is done in early boot, before IRQs are enabled.
2238  *
2239  * As a rule these aren't called more than once (except for drivers
2240  * using the open-drain emulation idiom) so these are natural places
2241  * to accumulate extra debugging checks.  Note that we can't (yet)
2242  * rely on gpio_request() having been called beforehand.
2243  */
2244 
2245 static int gpio_do_set_config(struct gpio_chip *gc, unsigned int offset,
2246 			      unsigned long config)
2247 {
2248 	if (!gc->set_config)
2249 		return -ENOTSUPP;
2250 
2251 	return gc->set_config(gc, offset, config);
2252 }
2253 
2254 static int gpio_set_config(struct gpio_desc *desc, enum pin_config_param mode)
2255 {
2256 	struct gpio_chip *gc = desc->gdev->chip;
2257 	unsigned long config;
2258 	unsigned arg;
2259 
2260 	switch (mode) {
2261 	case PIN_CONFIG_BIAS_PULL_DOWN:
2262 	case PIN_CONFIG_BIAS_PULL_UP:
2263 		arg = 1;
2264 		break;
2265 
2266 	default:
2267 		arg = 0;
2268 	}
2269 
2270 	config = PIN_CONF_PACKED(mode, arg);
2271 	return gpio_do_set_config(gc, gpio_chip_hwgpio(desc), config);
2272 }
2273 
2274 static int gpio_set_bias(struct gpio_desc *desc)
2275 {
2276 	int bias = 0;
2277 	int ret = 0;
2278 
2279 	if (test_bit(FLAG_BIAS_DISABLE, &desc->flags))
2280 		bias = PIN_CONFIG_BIAS_DISABLE;
2281 	else if (test_bit(FLAG_PULL_UP, &desc->flags))
2282 		bias = PIN_CONFIG_BIAS_PULL_UP;
2283 	else if (test_bit(FLAG_PULL_DOWN, &desc->flags))
2284 		bias = PIN_CONFIG_BIAS_PULL_DOWN;
2285 
2286 	if (bias) {
2287 		ret = gpio_set_config(desc, bias);
2288 		if (ret != -ENOTSUPP)
2289 			return ret;
2290 	}
2291 	return 0;
2292 }
2293 
2294 /**
2295  * gpiod_direction_input - set the GPIO direction to input
2296  * @desc:	GPIO to set to input
2297  *
2298  * Set the direction of the passed GPIO to input, such as gpiod_get_value() can
2299  * be called safely on it.
2300  *
2301  * Return 0 in case of success, else an error code.
2302  */
2303 int gpiod_direction_input(struct gpio_desc *desc)
2304 {
2305 	struct gpio_chip	*gc;
2306 	int			ret = 0;
2307 
2308 	VALIDATE_DESC(desc);
2309 	gc = desc->gdev->chip;
2310 
2311 	/*
2312 	 * It is legal to have no .get() and .direction_input() specified if
2313 	 * the chip is output-only, but you can't specify .direction_input()
2314 	 * and not support the .get() operation, that doesn't make sense.
2315 	 */
2316 	if (!gc->get && gc->direction_input) {
2317 		gpiod_warn(desc,
2318 			   "%s: missing get() but have direction_input()\n",
2319 			   __func__);
2320 		return -EIO;
2321 	}
2322 
2323 	/*
2324 	 * If we have a .direction_input() callback, things are simple,
2325 	 * just call it. Else we are some input-only chip so try to check the
2326 	 * direction (if .get_direction() is supported) else we silently
2327 	 * assume we are in input mode after this.
2328 	 */
2329 	if (gc->direction_input) {
2330 		ret = gc->direction_input(gc, gpio_chip_hwgpio(desc));
2331 	} else if (gc->get_direction &&
2332 		  (gc->get_direction(gc, gpio_chip_hwgpio(desc)) != 1)) {
2333 		gpiod_warn(desc,
2334 			   "%s: missing direction_input() operation and line is output\n",
2335 			   __func__);
2336 		return -EIO;
2337 	}
2338 	if (ret == 0) {
2339 		clear_bit(FLAG_IS_OUT, &desc->flags);
2340 		ret = gpio_set_bias(desc);
2341 	}
2342 
2343 	trace_gpio_direction(desc_to_gpio(desc), 1, ret);
2344 
2345 	return ret;
2346 }
2347 EXPORT_SYMBOL_GPL(gpiod_direction_input);
2348 
2349 static int gpiod_direction_output_raw_commit(struct gpio_desc *desc, int value)
2350 {
2351 	struct gpio_chip *gc = desc->gdev->chip;
2352 	int val = !!value;
2353 	int ret = 0;
2354 
2355 	/*
2356 	 * It's OK not to specify .direction_output() if the gpiochip is
2357 	 * output-only, but if there is then not even a .set() operation it
2358 	 * is pretty tricky to drive the output line.
2359 	 */
2360 	if (!gc->set && !gc->direction_output) {
2361 		gpiod_warn(desc,
2362 			   "%s: missing set() and direction_output() operations\n",
2363 			   __func__);
2364 		return -EIO;
2365 	}
2366 
2367 	if (gc->direction_output) {
2368 		ret = gc->direction_output(gc, gpio_chip_hwgpio(desc), val);
2369 	} else {
2370 		/* Check that we are in output mode if we can */
2371 		if (gc->get_direction &&
2372 		    gc->get_direction(gc, gpio_chip_hwgpio(desc))) {
2373 			gpiod_warn(desc,
2374 				"%s: missing direction_output() operation\n",
2375 				__func__);
2376 			return -EIO;
2377 		}
2378 		/*
2379 		 * If we can't actively set the direction, we are some
2380 		 * output-only chip, so just drive the output as desired.
2381 		 */
2382 		gc->set(gc, gpio_chip_hwgpio(desc), val);
2383 	}
2384 
2385 	if (!ret)
2386 		set_bit(FLAG_IS_OUT, &desc->flags);
2387 	trace_gpio_value(desc_to_gpio(desc), 0, val);
2388 	trace_gpio_direction(desc_to_gpio(desc), 0, ret);
2389 	return ret;
2390 }
2391 
2392 /**
2393  * gpiod_direction_output_raw - set the GPIO direction to output
2394  * @desc:	GPIO to set to output
2395  * @value:	initial output value of the GPIO
2396  *
2397  * Set the direction of the passed GPIO to output, such as gpiod_set_value() can
2398  * be called safely on it. The initial value of the output must be specified
2399  * as raw value on the physical line without regard for the ACTIVE_LOW status.
2400  *
2401  * Return 0 in case of success, else an error code.
2402  */
2403 int gpiod_direction_output_raw(struct gpio_desc *desc, int value)
2404 {
2405 	VALIDATE_DESC(desc);
2406 	return gpiod_direction_output_raw_commit(desc, value);
2407 }
2408 EXPORT_SYMBOL_GPL(gpiod_direction_output_raw);
2409 
2410 /**
2411  * gpiod_direction_output - set the GPIO direction to output
2412  * @desc:	GPIO to set to output
2413  * @value:	initial output value of the GPIO
2414  *
2415  * Set the direction of the passed GPIO to output, such as gpiod_set_value() can
2416  * be called safely on it. The initial value of the output must be specified
2417  * as the logical value of the GPIO, i.e. taking its ACTIVE_LOW status into
2418  * account.
2419  *
2420  * Return 0 in case of success, else an error code.
2421  */
2422 int gpiod_direction_output(struct gpio_desc *desc, int value)
2423 {
2424 	int ret;
2425 
2426 	VALIDATE_DESC(desc);
2427 	if (test_bit(FLAG_ACTIVE_LOW, &desc->flags))
2428 		value = !value;
2429 	else
2430 		value = !!value;
2431 
2432 	/* GPIOs used for enabled IRQs shall not be set as output */
2433 	if (test_bit(FLAG_USED_AS_IRQ, &desc->flags) &&
2434 	    test_bit(FLAG_IRQ_IS_ENABLED, &desc->flags)) {
2435 		gpiod_err(desc,
2436 			  "%s: tried to set a GPIO tied to an IRQ as output\n",
2437 			  __func__);
2438 		return -EIO;
2439 	}
2440 
2441 	if (test_bit(FLAG_OPEN_DRAIN, &desc->flags)) {
2442 		/* First see if we can enable open drain in hardware */
2443 		ret = gpio_set_config(desc, PIN_CONFIG_DRIVE_OPEN_DRAIN);
2444 		if (!ret)
2445 			goto set_output_value;
2446 		/* Emulate open drain by not actively driving the line high */
2447 		if (value) {
2448 			ret = gpiod_direction_input(desc);
2449 			goto set_output_flag;
2450 		}
2451 	}
2452 	else if (test_bit(FLAG_OPEN_SOURCE, &desc->flags)) {
2453 		ret = gpio_set_config(desc, PIN_CONFIG_DRIVE_OPEN_SOURCE);
2454 		if (!ret)
2455 			goto set_output_value;
2456 		/* Emulate open source by not actively driving the line low */
2457 		if (!value) {
2458 			ret = gpiod_direction_input(desc);
2459 			goto set_output_flag;
2460 		}
2461 	} else {
2462 		gpio_set_config(desc, PIN_CONFIG_DRIVE_PUSH_PULL);
2463 	}
2464 
2465 set_output_value:
2466 	ret = gpio_set_bias(desc);
2467 	if (ret)
2468 		return ret;
2469 	return gpiod_direction_output_raw_commit(desc, value);
2470 
2471 set_output_flag:
2472 	/*
2473 	 * When emulating open-source or open-drain functionalities by not
2474 	 * actively driving the line (setting mode to input) we still need to
2475 	 * set the IS_OUT flag or otherwise we won't be able to set the line
2476 	 * value anymore.
2477 	 */
2478 	if (ret == 0)
2479 		set_bit(FLAG_IS_OUT, &desc->flags);
2480 	return ret;
2481 }
2482 EXPORT_SYMBOL_GPL(gpiod_direction_output);
2483 
2484 /**
2485  * gpiod_set_config - sets @config for a GPIO
2486  * @desc: descriptor of the GPIO for which to set the configuration
2487  * @config: Same packed config format as generic pinconf
2488  *
2489  * Returns:
2490  * 0 on success, %-ENOTSUPP if the controller doesn't support setting the
2491  * configuration.
2492  */
2493 int gpiod_set_config(struct gpio_desc *desc, unsigned long config)
2494 {
2495 	struct gpio_chip *gc;
2496 
2497 	VALIDATE_DESC(desc);
2498 	gc = desc->gdev->chip;
2499 
2500 	return gpio_do_set_config(gc, gpio_chip_hwgpio(desc), config);
2501 }
2502 EXPORT_SYMBOL_GPL(gpiod_set_config);
2503 
2504 /**
2505  * gpiod_set_debounce - sets @debounce time for a GPIO
2506  * @desc: descriptor of the GPIO for which to set debounce time
2507  * @debounce: debounce time in microseconds
2508  *
2509  * Returns:
2510  * 0 on success, %-ENOTSUPP if the controller doesn't support setting the
2511  * debounce time.
2512  */
2513 int gpiod_set_debounce(struct gpio_desc *desc, unsigned debounce)
2514 {
2515 	unsigned long config;
2516 
2517 	config = pinconf_to_config_packed(PIN_CONFIG_INPUT_DEBOUNCE, debounce);
2518 	return gpiod_set_config(desc, config);
2519 }
2520 EXPORT_SYMBOL_GPL(gpiod_set_debounce);
2521 
2522 /**
2523  * gpiod_set_transitory - Lose or retain GPIO state on suspend or reset
2524  * @desc: descriptor of the GPIO for which to configure persistence
2525  * @transitory: True to lose state on suspend or reset, false for persistence
2526  *
2527  * Returns:
2528  * 0 on success, otherwise a negative error code.
2529  */
2530 int gpiod_set_transitory(struct gpio_desc *desc, bool transitory)
2531 {
2532 	struct gpio_chip *gc;
2533 	unsigned long packed;
2534 	int gpio;
2535 	int rc;
2536 
2537 	VALIDATE_DESC(desc);
2538 	/*
2539 	 * Handle FLAG_TRANSITORY first, enabling queries to gpiolib for
2540 	 * persistence state.
2541 	 */
2542 	assign_bit(FLAG_TRANSITORY, &desc->flags, transitory);
2543 
2544 	/* If the driver supports it, set the persistence state now */
2545 	gc = desc->gdev->chip;
2546 	if (!gc->set_config)
2547 		return 0;
2548 
2549 	packed = pinconf_to_config_packed(PIN_CONFIG_PERSIST_STATE,
2550 					  !transitory);
2551 	gpio = gpio_chip_hwgpio(desc);
2552 	rc = gpio_do_set_config(gc, gpio, packed);
2553 	if (rc == -ENOTSUPP) {
2554 		dev_dbg(&desc->gdev->dev, "Persistence not supported for GPIO %d\n",
2555 				gpio);
2556 		return 0;
2557 	}
2558 
2559 	return rc;
2560 }
2561 EXPORT_SYMBOL_GPL(gpiod_set_transitory);
2562 
2563 /**
2564  * gpiod_is_active_low - test whether a GPIO is active-low or not
2565  * @desc: the gpio descriptor to test
2566  *
2567  * Returns 1 if the GPIO is active-low, 0 otherwise.
2568  */
2569 int gpiod_is_active_low(const struct gpio_desc *desc)
2570 {
2571 	VALIDATE_DESC(desc);
2572 	return test_bit(FLAG_ACTIVE_LOW, &desc->flags);
2573 }
2574 EXPORT_SYMBOL_GPL(gpiod_is_active_low);
2575 
2576 /**
2577  * gpiod_toggle_active_low - toggle whether a GPIO is active-low or not
2578  * @desc: the gpio descriptor to change
2579  */
2580 void gpiod_toggle_active_low(struct gpio_desc *desc)
2581 {
2582 	VALIDATE_DESC_VOID(desc);
2583 	change_bit(FLAG_ACTIVE_LOW, &desc->flags);
2584 }
2585 EXPORT_SYMBOL_GPL(gpiod_toggle_active_low);
2586 
2587 /* I/O calls are only valid after configuration completed; the relevant
2588  * "is this a valid GPIO" error checks should already have been done.
2589  *
2590  * "Get" operations are often inlinable as reading a pin value register,
2591  * and masking the relevant bit in that register.
2592  *
2593  * When "set" operations are inlinable, they involve writing that mask to
2594  * one register to set a low value, or a different register to set it high.
2595  * Otherwise locking is needed, so there may be little value to inlining.
2596  *
2597  *------------------------------------------------------------------------
2598  *
2599  * IMPORTANT!!!  The hot paths -- get/set value -- assume that callers
2600  * have requested the GPIO.  That can include implicit requesting by
2601  * a direction setting call.  Marking a gpio as requested locks its chip
2602  * in memory, guaranteeing that these table lookups need no more locking
2603  * and that gpiochip_remove() will fail.
2604  *
2605  * REVISIT when debugging, consider adding some instrumentation to ensure
2606  * that the GPIO was actually requested.
2607  */
2608 
2609 static int gpiod_get_raw_value_commit(const struct gpio_desc *desc)
2610 {
2611 	struct gpio_chip	*gc;
2612 	int offset;
2613 	int value;
2614 
2615 	gc = desc->gdev->chip;
2616 	offset = gpio_chip_hwgpio(desc);
2617 	value = gc->get ? gc->get(gc, offset) : -EIO;
2618 	value = value < 0 ? value : !!value;
2619 	trace_gpio_value(desc_to_gpio(desc), 1, value);
2620 	return value;
2621 }
2622 
2623 static int gpio_chip_get_multiple(struct gpio_chip *gc,
2624 				  unsigned long *mask, unsigned long *bits)
2625 {
2626 	if (gc->get_multiple) {
2627 		return gc->get_multiple(gc, mask, bits);
2628 	} else if (gc->get) {
2629 		int i, value;
2630 
2631 		for_each_set_bit(i, mask, gc->ngpio) {
2632 			value = gc->get(gc, i);
2633 			if (value < 0)
2634 				return value;
2635 			__assign_bit(i, bits, value);
2636 		}
2637 		return 0;
2638 	}
2639 	return -EIO;
2640 }
2641 
2642 int gpiod_get_array_value_complex(bool raw, bool can_sleep,
2643 				  unsigned int array_size,
2644 				  struct gpio_desc **desc_array,
2645 				  struct gpio_array *array_info,
2646 				  unsigned long *value_bitmap)
2647 {
2648 	int ret, i = 0;
2649 
2650 	/*
2651 	 * Validate array_info against desc_array and its size.
2652 	 * It should immediately follow desc_array if both
2653 	 * have been obtained from the same gpiod_get_array() call.
2654 	 */
2655 	if (array_info && array_info->desc == desc_array &&
2656 	    array_size <= array_info->size &&
2657 	    (void *)array_info == desc_array + array_info->size) {
2658 		if (!can_sleep)
2659 			WARN_ON(array_info->chip->can_sleep);
2660 
2661 		ret = gpio_chip_get_multiple(array_info->chip,
2662 					     array_info->get_mask,
2663 					     value_bitmap);
2664 		if (ret)
2665 			return ret;
2666 
2667 		if (!raw && !bitmap_empty(array_info->invert_mask, array_size))
2668 			bitmap_xor(value_bitmap, value_bitmap,
2669 				   array_info->invert_mask, array_size);
2670 
2671 		i = find_first_zero_bit(array_info->get_mask, array_size);
2672 		if (i == array_size)
2673 			return 0;
2674 	} else {
2675 		array_info = NULL;
2676 	}
2677 
2678 	while (i < array_size) {
2679 		struct gpio_chip *gc = desc_array[i]->gdev->chip;
2680 		unsigned long fastpath[2 * BITS_TO_LONGS(FASTPATH_NGPIO)];
2681 		unsigned long *mask, *bits;
2682 		int first, j, ret;
2683 
2684 		if (likely(gc->ngpio <= FASTPATH_NGPIO)) {
2685 			mask = fastpath;
2686 		} else {
2687 			mask = kmalloc_array(2 * BITS_TO_LONGS(gc->ngpio),
2688 					   sizeof(*mask),
2689 					   can_sleep ? GFP_KERNEL : GFP_ATOMIC);
2690 			if (!mask)
2691 				return -ENOMEM;
2692 		}
2693 
2694 		bits = mask + BITS_TO_LONGS(gc->ngpio);
2695 		bitmap_zero(mask, gc->ngpio);
2696 
2697 		if (!can_sleep)
2698 			WARN_ON(gc->can_sleep);
2699 
2700 		/* collect all inputs belonging to the same chip */
2701 		first = i;
2702 		do {
2703 			const struct gpio_desc *desc = desc_array[i];
2704 			int hwgpio = gpio_chip_hwgpio(desc);
2705 
2706 			__set_bit(hwgpio, mask);
2707 			i++;
2708 
2709 			if (array_info)
2710 				i = find_next_zero_bit(array_info->get_mask,
2711 						       array_size, i);
2712 		} while ((i < array_size) &&
2713 			 (desc_array[i]->gdev->chip == gc));
2714 
2715 		ret = gpio_chip_get_multiple(gc, mask, bits);
2716 		if (ret) {
2717 			if (mask != fastpath)
2718 				kfree(mask);
2719 			return ret;
2720 		}
2721 
2722 		for (j = first; j < i; ) {
2723 			const struct gpio_desc *desc = desc_array[j];
2724 			int hwgpio = gpio_chip_hwgpio(desc);
2725 			int value = test_bit(hwgpio, bits);
2726 
2727 			if (!raw && test_bit(FLAG_ACTIVE_LOW, &desc->flags))
2728 				value = !value;
2729 			__assign_bit(j, value_bitmap, value);
2730 			trace_gpio_value(desc_to_gpio(desc), 1, value);
2731 			j++;
2732 
2733 			if (array_info)
2734 				j = find_next_zero_bit(array_info->get_mask, i,
2735 						       j);
2736 		}
2737 
2738 		if (mask != fastpath)
2739 			kfree(mask);
2740 	}
2741 	return 0;
2742 }
2743 
2744 /**
2745  * gpiod_get_raw_value() - return a gpio's raw value
2746  * @desc: gpio whose value will be returned
2747  *
2748  * Return the GPIO's raw value, i.e. the value of the physical line disregarding
2749  * its ACTIVE_LOW status, or negative errno on failure.
2750  *
2751  * This function can be called from contexts where we cannot sleep, and will
2752  * complain if the GPIO chip functions potentially sleep.
2753  */
2754 int gpiod_get_raw_value(const struct gpio_desc *desc)
2755 {
2756 	VALIDATE_DESC(desc);
2757 	/* Should be using gpiod_get_raw_value_cansleep() */
2758 	WARN_ON(desc->gdev->chip->can_sleep);
2759 	return gpiod_get_raw_value_commit(desc);
2760 }
2761 EXPORT_SYMBOL_GPL(gpiod_get_raw_value);
2762 
2763 /**
2764  * gpiod_get_value() - return a gpio's value
2765  * @desc: gpio whose value will be returned
2766  *
2767  * Return the GPIO's logical value, i.e. taking the ACTIVE_LOW status into
2768  * account, or negative errno on failure.
2769  *
2770  * This function can be called from contexts where we cannot sleep, and will
2771  * complain if the GPIO chip functions potentially sleep.
2772  */
2773 int gpiod_get_value(const struct gpio_desc *desc)
2774 {
2775 	int value;
2776 
2777 	VALIDATE_DESC(desc);
2778 	/* Should be using gpiod_get_value_cansleep() */
2779 	WARN_ON(desc->gdev->chip->can_sleep);
2780 
2781 	value = gpiod_get_raw_value_commit(desc);
2782 	if (value < 0)
2783 		return value;
2784 
2785 	if (test_bit(FLAG_ACTIVE_LOW, &desc->flags))
2786 		value = !value;
2787 
2788 	return value;
2789 }
2790 EXPORT_SYMBOL_GPL(gpiod_get_value);
2791 
2792 /**
2793  * gpiod_get_raw_array_value() - read raw values from an array of GPIOs
2794  * @array_size: number of elements in the descriptor array / value bitmap
2795  * @desc_array: array of GPIO descriptors whose values will be read
2796  * @array_info: information on applicability of fast bitmap processing path
2797  * @value_bitmap: bitmap to store the read values
2798  *
2799  * Read the raw values of the GPIOs, i.e. the values of the physical lines
2800  * without regard for their ACTIVE_LOW status.  Return 0 in case of success,
2801  * else an error code.
2802  *
2803  * This function can be called from contexts where we cannot sleep,
2804  * and it will complain if the GPIO chip functions potentially sleep.
2805  */
2806 int gpiod_get_raw_array_value(unsigned int array_size,
2807 			      struct gpio_desc **desc_array,
2808 			      struct gpio_array *array_info,
2809 			      unsigned long *value_bitmap)
2810 {
2811 	if (!desc_array)
2812 		return -EINVAL;
2813 	return gpiod_get_array_value_complex(true, false, array_size,
2814 					     desc_array, array_info,
2815 					     value_bitmap);
2816 }
2817 EXPORT_SYMBOL_GPL(gpiod_get_raw_array_value);
2818 
2819 /**
2820  * gpiod_get_array_value() - read values from an array of GPIOs
2821  * @array_size: number of elements in the descriptor array / value bitmap
2822  * @desc_array: array of GPIO descriptors whose values will be read
2823  * @array_info: information on applicability of fast bitmap processing path
2824  * @value_bitmap: bitmap to store the read values
2825  *
2826  * Read the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status
2827  * into account.  Return 0 in case of success, else an error code.
2828  *
2829  * This function can be called from contexts where we cannot sleep,
2830  * and it will complain if the GPIO chip functions potentially sleep.
2831  */
2832 int gpiod_get_array_value(unsigned int array_size,
2833 			  struct gpio_desc **desc_array,
2834 			  struct gpio_array *array_info,
2835 			  unsigned long *value_bitmap)
2836 {
2837 	if (!desc_array)
2838 		return -EINVAL;
2839 	return gpiod_get_array_value_complex(false, false, array_size,
2840 					     desc_array, array_info,
2841 					     value_bitmap);
2842 }
2843 EXPORT_SYMBOL_GPL(gpiod_get_array_value);
2844 
2845 /*
2846  *  gpio_set_open_drain_value_commit() - Set the open drain gpio's value.
2847  * @desc: gpio descriptor whose state need to be set.
2848  * @value: Non-zero for setting it HIGH otherwise it will set to LOW.
2849  */
2850 static void gpio_set_open_drain_value_commit(struct gpio_desc *desc, bool value)
2851 {
2852 	int ret = 0;
2853 	struct gpio_chip *gc = desc->gdev->chip;
2854 	int offset = gpio_chip_hwgpio(desc);
2855 
2856 	if (value) {
2857 		ret = gc->direction_input(gc, offset);
2858 	} else {
2859 		ret = gc->direction_output(gc, offset, 0);
2860 		if (!ret)
2861 			set_bit(FLAG_IS_OUT, &desc->flags);
2862 	}
2863 	trace_gpio_direction(desc_to_gpio(desc), value, ret);
2864 	if (ret < 0)
2865 		gpiod_err(desc,
2866 			  "%s: Error in set_value for open drain err %d\n",
2867 			  __func__, ret);
2868 }
2869 
2870 /*
2871  *  _gpio_set_open_source_value() - Set the open source gpio's value.
2872  * @desc: gpio descriptor whose state need to be set.
2873  * @value: Non-zero for setting it HIGH otherwise it will set to LOW.
2874  */
2875 static void gpio_set_open_source_value_commit(struct gpio_desc *desc, bool value)
2876 {
2877 	int ret = 0;
2878 	struct gpio_chip *gc = desc->gdev->chip;
2879 	int offset = gpio_chip_hwgpio(desc);
2880 
2881 	if (value) {
2882 		ret = gc->direction_output(gc, offset, 1);
2883 		if (!ret)
2884 			set_bit(FLAG_IS_OUT, &desc->flags);
2885 	} else {
2886 		ret = gc->direction_input(gc, offset);
2887 	}
2888 	trace_gpio_direction(desc_to_gpio(desc), !value, ret);
2889 	if (ret < 0)
2890 		gpiod_err(desc,
2891 			  "%s: Error in set_value for open source err %d\n",
2892 			  __func__, ret);
2893 }
2894 
2895 static void gpiod_set_raw_value_commit(struct gpio_desc *desc, bool value)
2896 {
2897 	struct gpio_chip	*gc;
2898 
2899 	gc = desc->gdev->chip;
2900 	trace_gpio_value(desc_to_gpio(desc), 0, value);
2901 	gc->set(gc, gpio_chip_hwgpio(desc), value);
2902 }
2903 
2904 /*
2905  * set multiple outputs on the same chip;
2906  * use the chip's set_multiple function if available;
2907  * otherwise set the outputs sequentially;
2908  * @chip: the GPIO chip we operate on
2909  * @mask: bit mask array; one bit per output; BITS_PER_LONG bits per word
2910  *        defines which outputs are to be changed
2911  * @bits: bit value array; one bit per output; BITS_PER_LONG bits per word
2912  *        defines the values the outputs specified by mask are to be set to
2913  */
2914 static void gpio_chip_set_multiple(struct gpio_chip *gc,
2915 				   unsigned long *mask, unsigned long *bits)
2916 {
2917 	if (gc->set_multiple) {
2918 		gc->set_multiple(gc, mask, bits);
2919 	} else {
2920 		unsigned int i;
2921 
2922 		/* set outputs if the corresponding mask bit is set */
2923 		for_each_set_bit(i, mask, gc->ngpio)
2924 			gc->set(gc, i, test_bit(i, bits));
2925 	}
2926 }
2927 
2928 int gpiod_set_array_value_complex(bool raw, bool can_sleep,
2929 				  unsigned int array_size,
2930 				  struct gpio_desc **desc_array,
2931 				  struct gpio_array *array_info,
2932 				  unsigned long *value_bitmap)
2933 {
2934 	int i = 0;
2935 
2936 	/*
2937 	 * Validate array_info against desc_array and its size.
2938 	 * It should immediately follow desc_array if both
2939 	 * have been obtained from the same gpiod_get_array() call.
2940 	 */
2941 	if (array_info && array_info->desc == desc_array &&
2942 	    array_size <= array_info->size &&
2943 	    (void *)array_info == desc_array + array_info->size) {
2944 		if (!can_sleep)
2945 			WARN_ON(array_info->chip->can_sleep);
2946 
2947 		if (!raw && !bitmap_empty(array_info->invert_mask, array_size))
2948 			bitmap_xor(value_bitmap, value_bitmap,
2949 				   array_info->invert_mask, array_size);
2950 
2951 		gpio_chip_set_multiple(array_info->chip, array_info->set_mask,
2952 				       value_bitmap);
2953 
2954 		i = find_first_zero_bit(array_info->set_mask, array_size);
2955 		if (i == array_size)
2956 			return 0;
2957 	} else {
2958 		array_info = NULL;
2959 	}
2960 
2961 	while (i < array_size) {
2962 		struct gpio_chip *gc = desc_array[i]->gdev->chip;
2963 		unsigned long fastpath[2 * BITS_TO_LONGS(FASTPATH_NGPIO)];
2964 		unsigned long *mask, *bits;
2965 		int count = 0;
2966 
2967 		if (likely(gc->ngpio <= FASTPATH_NGPIO)) {
2968 			mask = fastpath;
2969 		} else {
2970 			mask = kmalloc_array(2 * BITS_TO_LONGS(gc->ngpio),
2971 					   sizeof(*mask),
2972 					   can_sleep ? GFP_KERNEL : GFP_ATOMIC);
2973 			if (!mask)
2974 				return -ENOMEM;
2975 		}
2976 
2977 		bits = mask + BITS_TO_LONGS(gc->ngpio);
2978 		bitmap_zero(mask, gc->ngpio);
2979 
2980 		if (!can_sleep)
2981 			WARN_ON(gc->can_sleep);
2982 
2983 		do {
2984 			struct gpio_desc *desc = desc_array[i];
2985 			int hwgpio = gpio_chip_hwgpio(desc);
2986 			int value = test_bit(i, value_bitmap);
2987 
2988 			/*
2989 			 * Pins applicable for fast input but not for
2990 			 * fast output processing may have been already
2991 			 * inverted inside the fast path, skip them.
2992 			 */
2993 			if (!raw && !(array_info &&
2994 			    test_bit(i, array_info->invert_mask)) &&
2995 			    test_bit(FLAG_ACTIVE_LOW, &desc->flags))
2996 				value = !value;
2997 			trace_gpio_value(desc_to_gpio(desc), 0, value);
2998 			/*
2999 			 * collect all normal outputs belonging to the same chip
3000 			 * open drain and open source outputs are set individually
3001 			 */
3002 			if (test_bit(FLAG_OPEN_DRAIN, &desc->flags) && !raw) {
3003 				gpio_set_open_drain_value_commit(desc, value);
3004 			} else if (test_bit(FLAG_OPEN_SOURCE, &desc->flags) && !raw) {
3005 				gpio_set_open_source_value_commit(desc, value);
3006 			} else {
3007 				__set_bit(hwgpio, mask);
3008 				__assign_bit(hwgpio, bits, value);
3009 				count++;
3010 			}
3011 			i++;
3012 
3013 			if (array_info)
3014 				i = find_next_zero_bit(array_info->set_mask,
3015 						       array_size, i);
3016 		} while ((i < array_size) &&
3017 			 (desc_array[i]->gdev->chip == gc));
3018 		/* push collected bits to outputs */
3019 		if (count != 0)
3020 			gpio_chip_set_multiple(gc, mask, bits);
3021 
3022 		if (mask != fastpath)
3023 			kfree(mask);
3024 	}
3025 	return 0;
3026 }
3027 
3028 /**
3029  * gpiod_set_raw_value() - assign a gpio's raw value
3030  * @desc: gpio whose value will be assigned
3031  * @value: value to assign
3032  *
3033  * Set the raw value of the GPIO, i.e. the value of its physical line without
3034  * regard for its ACTIVE_LOW status.
3035  *
3036  * This function can be called from contexts where we cannot sleep, and will
3037  * complain if the GPIO chip functions potentially sleep.
3038  */
3039 void gpiod_set_raw_value(struct gpio_desc *desc, int value)
3040 {
3041 	VALIDATE_DESC_VOID(desc);
3042 	/* Should be using gpiod_set_raw_value_cansleep() */
3043 	WARN_ON(desc->gdev->chip->can_sleep);
3044 	gpiod_set_raw_value_commit(desc, value);
3045 }
3046 EXPORT_SYMBOL_GPL(gpiod_set_raw_value);
3047 
3048 /**
3049  * gpiod_set_value_nocheck() - set a GPIO line value without checking
3050  * @desc: the descriptor to set the value on
3051  * @value: value to set
3052  *
3053  * This sets the value of a GPIO line backing a descriptor, applying
3054  * different semantic quirks like active low and open drain/source
3055  * handling.
3056  */
3057 static void gpiod_set_value_nocheck(struct gpio_desc *desc, int value)
3058 {
3059 	if (test_bit(FLAG_ACTIVE_LOW, &desc->flags))
3060 		value = !value;
3061 	if (test_bit(FLAG_OPEN_DRAIN, &desc->flags))
3062 		gpio_set_open_drain_value_commit(desc, value);
3063 	else if (test_bit(FLAG_OPEN_SOURCE, &desc->flags))
3064 		gpio_set_open_source_value_commit(desc, value);
3065 	else
3066 		gpiod_set_raw_value_commit(desc, value);
3067 }
3068 
3069 /**
3070  * gpiod_set_value() - assign a gpio's value
3071  * @desc: gpio whose value will be assigned
3072  * @value: value to assign
3073  *
3074  * Set the logical value of the GPIO, i.e. taking its ACTIVE_LOW,
3075  * OPEN_DRAIN and OPEN_SOURCE flags into account.
3076  *
3077  * This function can be called from contexts where we cannot sleep, and will
3078  * complain if the GPIO chip functions potentially sleep.
3079  */
3080 void gpiod_set_value(struct gpio_desc *desc, int value)
3081 {
3082 	VALIDATE_DESC_VOID(desc);
3083 	/* Should be using gpiod_set_value_cansleep() */
3084 	WARN_ON(desc->gdev->chip->can_sleep);
3085 	gpiod_set_value_nocheck(desc, value);
3086 }
3087 EXPORT_SYMBOL_GPL(gpiod_set_value);
3088 
3089 /**
3090  * gpiod_set_raw_array_value() - assign values to an array of GPIOs
3091  * @array_size: number of elements in the descriptor array / value bitmap
3092  * @desc_array: array of GPIO descriptors whose values will be assigned
3093  * @array_info: information on applicability of fast bitmap processing path
3094  * @value_bitmap: bitmap of values to assign
3095  *
3096  * Set the raw values of the GPIOs, i.e. the values of the physical lines
3097  * without regard for their ACTIVE_LOW status.
3098  *
3099  * This function can be called from contexts where we cannot sleep, and will
3100  * complain if the GPIO chip functions potentially sleep.
3101  */
3102 int gpiod_set_raw_array_value(unsigned int array_size,
3103 			      struct gpio_desc **desc_array,
3104 			      struct gpio_array *array_info,
3105 			      unsigned long *value_bitmap)
3106 {
3107 	if (!desc_array)
3108 		return -EINVAL;
3109 	return gpiod_set_array_value_complex(true, false, array_size,
3110 					desc_array, array_info, value_bitmap);
3111 }
3112 EXPORT_SYMBOL_GPL(gpiod_set_raw_array_value);
3113 
3114 /**
3115  * gpiod_set_array_value() - assign values to an array of GPIOs
3116  * @array_size: number of elements in the descriptor array / value bitmap
3117  * @desc_array: array of GPIO descriptors whose values will be assigned
3118  * @array_info: information on applicability of fast bitmap processing path
3119  * @value_bitmap: bitmap of values to assign
3120  *
3121  * Set the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status
3122  * into account.
3123  *
3124  * This function can be called from contexts where we cannot sleep, and will
3125  * complain if the GPIO chip functions potentially sleep.
3126  */
3127 int gpiod_set_array_value(unsigned int array_size,
3128 			  struct gpio_desc **desc_array,
3129 			  struct gpio_array *array_info,
3130 			  unsigned long *value_bitmap)
3131 {
3132 	if (!desc_array)
3133 		return -EINVAL;
3134 	return gpiod_set_array_value_complex(false, false, array_size,
3135 					     desc_array, array_info,
3136 					     value_bitmap);
3137 }
3138 EXPORT_SYMBOL_GPL(gpiod_set_array_value);
3139 
3140 /**
3141  * gpiod_cansleep() - report whether gpio value access may sleep
3142  * @desc: gpio to check
3143  *
3144  */
3145 int gpiod_cansleep(const struct gpio_desc *desc)
3146 {
3147 	VALIDATE_DESC(desc);
3148 	return desc->gdev->chip->can_sleep;
3149 }
3150 EXPORT_SYMBOL_GPL(gpiod_cansleep);
3151 
3152 /**
3153  * gpiod_set_consumer_name() - set the consumer name for the descriptor
3154  * @desc: gpio to set the consumer name on
3155  * @name: the new consumer name
3156  */
3157 int gpiod_set_consumer_name(struct gpio_desc *desc, const char *name)
3158 {
3159 	VALIDATE_DESC(desc);
3160 	if (name) {
3161 		name = kstrdup_const(name, GFP_KERNEL);
3162 		if (!name)
3163 			return -ENOMEM;
3164 	}
3165 
3166 	kfree_const(desc->label);
3167 	desc_set_label(desc, name);
3168 
3169 	return 0;
3170 }
3171 EXPORT_SYMBOL_GPL(gpiod_set_consumer_name);
3172 
3173 /**
3174  * gpiod_to_irq() - return the IRQ corresponding to a GPIO
3175  * @desc: gpio whose IRQ will be returned (already requested)
3176  *
3177  * Return the IRQ corresponding to the passed GPIO, or an error code in case of
3178  * error.
3179  */
3180 int gpiod_to_irq(const struct gpio_desc *desc)
3181 {
3182 	struct gpio_chip *gc;
3183 	int offset;
3184 
3185 	/*
3186 	 * Cannot VALIDATE_DESC() here as gpiod_to_irq() consumer semantics
3187 	 * requires this function to not return zero on an invalid descriptor
3188 	 * but rather a negative error number.
3189 	 */
3190 	if (!desc || IS_ERR(desc) || !desc->gdev || !desc->gdev->chip)
3191 		return -EINVAL;
3192 
3193 	gc = desc->gdev->chip;
3194 	offset = gpio_chip_hwgpio(desc);
3195 	if (gc->to_irq) {
3196 		int retirq = gc->to_irq(gc, offset);
3197 
3198 		/* Zero means NO_IRQ */
3199 		if (!retirq)
3200 			return -ENXIO;
3201 
3202 		return retirq;
3203 	}
3204 	return -ENXIO;
3205 }
3206 EXPORT_SYMBOL_GPL(gpiod_to_irq);
3207 
3208 /**
3209  * gpiochip_lock_as_irq() - lock a GPIO to be used as IRQ
3210  * @gc: the chip the GPIO to lock belongs to
3211  * @offset: the offset of the GPIO to lock as IRQ
3212  *
3213  * This is used directly by GPIO drivers that want to lock down
3214  * a certain GPIO line to be used for IRQs.
3215  */
3216 int gpiochip_lock_as_irq(struct gpio_chip *gc, unsigned int offset)
3217 {
3218 	struct gpio_desc *desc;
3219 
3220 	desc = gpiochip_get_desc(gc, offset);
3221 	if (IS_ERR(desc))
3222 		return PTR_ERR(desc);
3223 
3224 	/*
3225 	 * If it's fast: flush the direction setting if something changed
3226 	 * behind our back
3227 	 */
3228 	if (!gc->can_sleep && gc->get_direction) {
3229 		int dir = gpiod_get_direction(desc);
3230 
3231 		if (dir < 0) {
3232 			chip_err(gc, "%s: cannot get GPIO direction\n",
3233 				 __func__);
3234 			return dir;
3235 		}
3236 	}
3237 
3238 	/* To be valid for IRQ the line needs to be input or open drain */
3239 	if (test_bit(FLAG_IS_OUT, &desc->flags) &&
3240 	    !test_bit(FLAG_OPEN_DRAIN, &desc->flags)) {
3241 		chip_err(gc,
3242 			 "%s: tried to flag a GPIO set as output for IRQ\n",
3243 			 __func__);
3244 		return -EIO;
3245 	}
3246 
3247 	set_bit(FLAG_USED_AS_IRQ, &desc->flags);
3248 	set_bit(FLAG_IRQ_IS_ENABLED, &desc->flags);
3249 
3250 	/*
3251 	 * If the consumer has not set up a label (such as when the
3252 	 * IRQ is referenced from .to_irq()) we set up a label here
3253 	 * so it is clear this is used as an interrupt.
3254 	 */
3255 	if (!desc->label)
3256 		desc_set_label(desc, "interrupt");
3257 
3258 	return 0;
3259 }
3260 EXPORT_SYMBOL_GPL(gpiochip_lock_as_irq);
3261 
3262 /**
3263  * gpiochip_unlock_as_irq() - unlock a GPIO used as IRQ
3264  * @gc: the chip the GPIO to lock belongs to
3265  * @offset: the offset of the GPIO to lock as IRQ
3266  *
3267  * This is used directly by GPIO drivers that want to indicate
3268  * that a certain GPIO is no longer used exclusively for IRQ.
3269  */
3270 void gpiochip_unlock_as_irq(struct gpio_chip *gc, unsigned int offset)
3271 {
3272 	struct gpio_desc *desc;
3273 
3274 	desc = gpiochip_get_desc(gc, offset);
3275 	if (IS_ERR(desc))
3276 		return;
3277 
3278 	clear_bit(FLAG_USED_AS_IRQ, &desc->flags);
3279 	clear_bit(FLAG_IRQ_IS_ENABLED, &desc->flags);
3280 
3281 	/* If we only had this marking, erase it */
3282 	if (desc->label && !strcmp(desc->label, "interrupt"))
3283 		desc_set_label(desc, NULL);
3284 }
3285 EXPORT_SYMBOL_GPL(gpiochip_unlock_as_irq);
3286 
3287 void gpiochip_disable_irq(struct gpio_chip *gc, unsigned int offset)
3288 {
3289 	struct gpio_desc *desc = gpiochip_get_desc(gc, offset);
3290 
3291 	if (!IS_ERR(desc) &&
3292 	    !WARN_ON(!test_bit(FLAG_USED_AS_IRQ, &desc->flags)))
3293 		clear_bit(FLAG_IRQ_IS_ENABLED, &desc->flags);
3294 }
3295 EXPORT_SYMBOL_GPL(gpiochip_disable_irq);
3296 
3297 void gpiochip_enable_irq(struct gpio_chip *gc, unsigned int offset)
3298 {
3299 	struct gpio_desc *desc = gpiochip_get_desc(gc, offset);
3300 
3301 	if (!IS_ERR(desc) &&
3302 	    !WARN_ON(!test_bit(FLAG_USED_AS_IRQ, &desc->flags))) {
3303 		/*
3304 		 * We must not be output when using IRQ UNLESS we are
3305 		 * open drain.
3306 		 */
3307 		WARN_ON(test_bit(FLAG_IS_OUT, &desc->flags) &&
3308 			!test_bit(FLAG_OPEN_DRAIN, &desc->flags));
3309 		set_bit(FLAG_IRQ_IS_ENABLED, &desc->flags);
3310 	}
3311 }
3312 EXPORT_SYMBOL_GPL(gpiochip_enable_irq);
3313 
3314 bool gpiochip_line_is_irq(struct gpio_chip *gc, unsigned int offset)
3315 {
3316 	if (offset >= gc->ngpio)
3317 		return false;
3318 
3319 	return test_bit(FLAG_USED_AS_IRQ, &gc->gpiodev->descs[offset].flags);
3320 }
3321 EXPORT_SYMBOL_GPL(gpiochip_line_is_irq);
3322 
3323 int gpiochip_reqres_irq(struct gpio_chip *gc, unsigned int offset)
3324 {
3325 	int ret;
3326 
3327 	if (!try_module_get(gc->gpiodev->owner))
3328 		return -ENODEV;
3329 
3330 	ret = gpiochip_lock_as_irq(gc, offset);
3331 	if (ret) {
3332 		chip_err(gc, "unable to lock HW IRQ %u for IRQ\n", offset);
3333 		module_put(gc->gpiodev->owner);
3334 		return ret;
3335 	}
3336 	return 0;
3337 }
3338 EXPORT_SYMBOL_GPL(gpiochip_reqres_irq);
3339 
3340 void gpiochip_relres_irq(struct gpio_chip *gc, unsigned int offset)
3341 {
3342 	gpiochip_unlock_as_irq(gc, offset);
3343 	module_put(gc->gpiodev->owner);
3344 }
3345 EXPORT_SYMBOL_GPL(gpiochip_relres_irq);
3346 
3347 bool gpiochip_line_is_open_drain(struct gpio_chip *gc, unsigned int offset)
3348 {
3349 	if (offset >= gc->ngpio)
3350 		return false;
3351 
3352 	return test_bit(FLAG_OPEN_DRAIN, &gc->gpiodev->descs[offset].flags);
3353 }
3354 EXPORT_SYMBOL_GPL(gpiochip_line_is_open_drain);
3355 
3356 bool gpiochip_line_is_open_source(struct gpio_chip *gc, unsigned int offset)
3357 {
3358 	if (offset >= gc->ngpio)
3359 		return false;
3360 
3361 	return test_bit(FLAG_OPEN_SOURCE, &gc->gpiodev->descs[offset].flags);
3362 }
3363 EXPORT_SYMBOL_GPL(gpiochip_line_is_open_source);
3364 
3365 bool gpiochip_line_is_persistent(struct gpio_chip *gc, unsigned int offset)
3366 {
3367 	if (offset >= gc->ngpio)
3368 		return false;
3369 
3370 	return !test_bit(FLAG_TRANSITORY, &gc->gpiodev->descs[offset].flags);
3371 }
3372 EXPORT_SYMBOL_GPL(gpiochip_line_is_persistent);
3373 
3374 /**
3375  * gpiod_get_raw_value_cansleep() - return a gpio's raw value
3376  * @desc: gpio whose value will be returned
3377  *
3378  * Return the GPIO's raw value, i.e. the value of the physical line disregarding
3379  * its ACTIVE_LOW status, or negative errno on failure.
3380  *
3381  * This function is to be called from contexts that can sleep.
3382  */
3383 int gpiod_get_raw_value_cansleep(const struct gpio_desc *desc)
3384 {
3385 	might_sleep_if(extra_checks);
3386 	VALIDATE_DESC(desc);
3387 	return gpiod_get_raw_value_commit(desc);
3388 }
3389 EXPORT_SYMBOL_GPL(gpiod_get_raw_value_cansleep);
3390 
3391 /**
3392  * gpiod_get_value_cansleep() - return a gpio's value
3393  * @desc: gpio whose value will be returned
3394  *
3395  * Return the GPIO's logical value, i.e. taking the ACTIVE_LOW status into
3396  * account, or negative errno on failure.
3397  *
3398  * This function is to be called from contexts that can sleep.
3399  */
3400 int gpiod_get_value_cansleep(const struct gpio_desc *desc)
3401 {
3402 	int value;
3403 
3404 	might_sleep_if(extra_checks);
3405 	VALIDATE_DESC(desc);
3406 	value = gpiod_get_raw_value_commit(desc);
3407 	if (value < 0)
3408 		return value;
3409 
3410 	if (test_bit(FLAG_ACTIVE_LOW, &desc->flags))
3411 		value = !value;
3412 
3413 	return value;
3414 }
3415 EXPORT_SYMBOL_GPL(gpiod_get_value_cansleep);
3416 
3417 /**
3418  * gpiod_get_raw_array_value_cansleep() - read raw values from an array of GPIOs
3419  * @array_size: number of elements in the descriptor array / value bitmap
3420  * @desc_array: array of GPIO descriptors whose values will be read
3421  * @array_info: information on applicability of fast bitmap processing path
3422  * @value_bitmap: bitmap to store the read values
3423  *
3424  * Read the raw values of the GPIOs, i.e. the values of the physical lines
3425  * without regard for their ACTIVE_LOW status.  Return 0 in case of success,
3426  * else an error code.
3427  *
3428  * This function is to be called from contexts that can sleep.
3429  */
3430 int gpiod_get_raw_array_value_cansleep(unsigned int array_size,
3431 				       struct gpio_desc **desc_array,
3432 				       struct gpio_array *array_info,
3433 				       unsigned long *value_bitmap)
3434 {
3435 	might_sleep_if(extra_checks);
3436 	if (!desc_array)
3437 		return -EINVAL;
3438 	return gpiod_get_array_value_complex(true, true, array_size,
3439 					     desc_array, array_info,
3440 					     value_bitmap);
3441 }
3442 EXPORT_SYMBOL_GPL(gpiod_get_raw_array_value_cansleep);
3443 
3444 /**
3445  * gpiod_get_array_value_cansleep() - read values from an array of GPIOs
3446  * @array_size: number of elements in the descriptor array / value bitmap
3447  * @desc_array: array of GPIO descriptors whose values will be read
3448  * @array_info: information on applicability of fast bitmap processing path
3449  * @value_bitmap: bitmap to store the read values
3450  *
3451  * Read the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status
3452  * into account.  Return 0 in case of success, else an error code.
3453  *
3454  * This function is to be called from contexts that can sleep.
3455  */
3456 int gpiod_get_array_value_cansleep(unsigned int array_size,
3457 				   struct gpio_desc **desc_array,
3458 				   struct gpio_array *array_info,
3459 				   unsigned long *value_bitmap)
3460 {
3461 	might_sleep_if(extra_checks);
3462 	if (!desc_array)
3463 		return -EINVAL;
3464 	return gpiod_get_array_value_complex(false, true, array_size,
3465 					     desc_array, array_info,
3466 					     value_bitmap);
3467 }
3468 EXPORT_SYMBOL_GPL(gpiod_get_array_value_cansleep);
3469 
3470 /**
3471  * gpiod_set_raw_value_cansleep() - assign a gpio's raw value
3472  * @desc: gpio whose value will be assigned
3473  * @value: value to assign
3474  *
3475  * Set the raw value of the GPIO, i.e. the value of its physical line without
3476  * regard for its ACTIVE_LOW status.
3477  *
3478  * This function is to be called from contexts that can sleep.
3479  */
3480 void gpiod_set_raw_value_cansleep(struct gpio_desc *desc, int value)
3481 {
3482 	might_sleep_if(extra_checks);
3483 	VALIDATE_DESC_VOID(desc);
3484 	gpiod_set_raw_value_commit(desc, value);
3485 }
3486 EXPORT_SYMBOL_GPL(gpiod_set_raw_value_cansleep);
3487 
3488 /**
3489  * gpiod_set_value_cansleep() - assign a gpio's value
3490  * @desc: gpio whose value will be assigned
3491  * @value: value to assign
3492  *
3493  * Set the logical value of the GPIO, i.e. taking its ACTIVE_LOW status into
3494  * account
3495  *
3496  * This function is to be called from contexts that can sleep.
3497  */
3498 void gpiod_set_value_cansleep(struct gpio_desc *desc, int value)
3499 {
3500 	might_sleep_if(extra_checks);
3501 	VALIDATE_DESC_VOID(desc);
3502 	gpiod_set_value_nocheck(desc, value);
3503 }
3504 EXPORT_SYMBOL_GPL(gpiod_set_value_cansleep);
3505 
3506 /**
3507  * gpiod_set_raw_array_value_cansleep() - assign values to an array of GPIOs
3508  * @array_size: number of elements in the descriptor array / value bitmap
3509  * @desc_array: array of GPIO descriptors whose values will be assigned
3510  * @array_info: information on applicability of fast bitmap processing path
3511  * @value_bitmap: bitmap of values to assign
3512  *
3513  * Set the raw values of the GPIOs, i.e. the values of the physical lines
3514  * without regard for their ACTIVE_LOW status.
3515  *
3516  * This function is to be called from contexts that can sleep.
3517  */
3518 int gpiod_set_raw_array_value_cansleep(unsigned int array_size,
3519 				       struct gpio_desc **desc_array,
3520 				       struct gpio_array *array_info,
3521 				       unsigned long *value_bitmap)
3522 {
3523 	might_sleep_if(extra_checks);
3524 	if (!desc_array)
3525 		return -EINVAL;
3526 	return gpiod_set_array_value_complex(true, true, array_size, desc_array,
3527 				      array_info, value_bitmap);
3528 }
3529 EXPORT_SYMBOL_GPL(gpiod_set_raw_array_value_cansleep);
3530 
3531 /**
3532  * gpiod_add_lookup_tables() - register GPIO device consumers
3533  * @tables: list of tables of consumers to register
3534  * @n: number of tables in the list
3535  */
3536 void gpiod_add_lookup_tables(struct gpiod_lookup_table **tables, size_t n)
3537 {
3538 	unsigned int i;
3539 
3540 	mutex_lock(&gpio_lookup_lock);
3541 
3542 	for (i = 0; i < n; i++)
3543 		list_add_tail(&tables[i]->list, &gpio_lookup_list);
3544 
3545 	mutex_unlock(&gpio_lookup_lock);
3546 }
3547 
3548 /**
3549  * gpiod_set_array_value_cansleep() - assign values to an array of GPIOs
3550  * @array_size: number of elements in the descriptor array / value bitmap
3551  * @desc_array: array of GPIO descriptors whose values will be assigned
3552  * @array_info: information on applicability of fast bitmap processing path
3553  * @value_bitmap: bitmap of values to assign
3554  *
3555  * Set the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status
3556  * into account.
3557  *
3558  * This function is to be called from contexts that can sleep.
3559  */
3560 int gpiod_set_array_value_cansleep(unsigned int array_size,
3561 				   struct gpio_desc **desc_array,
3562 				   struct gpio_array *array_info,
3563 				   unsigned long *value_bitmap)
3564 {
3565 	might_sleep_if(extra_checks);
3566 	if (!desc_array)
3567 		return -EINVAL;
3568 	return gpiod_set_array_value_complex(false, true, array_size,
3569 					     desc_array, array_info,
3570 					     value_bitmap);
3571 }
3572 EXPORT_SYMBOL_GPL(gpiod_set_array_value_cansleep);
3573 
3574 /**
3575  * gpiod_add_lookup_table() - register GPIO device consumers
3576  * @table: table of consumers to register
3577  */
3578 void gpiod_add_lookup_table(struct gpiod_lookup_table *table)
3579 {
3580 	mutex_lock(&gpio_lookup_lock);
3581 
3582 	list_add_tail(&table->list, &gpio_lookup_list);
3583 
3584 	mutex_unlock(&gpio_lookup_lock);
3585 }
3586 EXPORT_SYMBOL_GPL(gpiod_add_lookup_table);
3587 
3588 /**
3589  * gpiod_remove_lookup_table() - unregister GPIO device consumers
3590  * @table: table of consumers to unregister
3591  */
3592 void gpiod_remove_lookup_table(struct gpiod_lookup_table *table)
3593 {
3594 	mutex_lock(&gpio_lookup_lock);
3595 
3596 	list_del(&table->list);
3597 
3598 	mutex_unlock(&gpio_lookup_lock);
3599 }
3600 EXPORT_SYMBOL_GPL(gpiod_remove_lookup_table);
3601 
3602 /**
3603  * gpiod_add_hogs() - register a set of GPIO hogs from machine code
3604  * @hogs: table of gpio hog entries with a zeroed sentinel at the end
3605  */
3606 void gpiod_add_hogs(struct gpiod_hog *hogs)
3607 {
3608 	struct gpio_chip *gc;
3609 	struct gpiod_hog *hog;
3610 
3611 	mutex_lock(&gpio_machine_hogs_mutex);
3612 
3613 	for (hog = &hogs[0]; hog->chip_label; hog++) {
3614 		list_add_tail(&hog->list, &gpio_machine_hogs);
3615 
3616 		/*
3617 		 * The chip may have been registered earlier, so check if it
3618 		 * exists and, if so, try to hog the line now.
3619 		 */
3620 		gc = find_chip_by_name(hog->chip_label);
3621 		if (gc)
3622 			gpiochip_machine_hog(gc, hog);
3623 	}
3624 
3625 	mutex_unlock(&gpio_machine_hogs_mutex);
3626 }
3627 EXPORT_SYMBOL_GPL(gpiod_add_hogs);
3628 
3629 static struct gpiod_lookup_table *gpiod_find_lookup_table(struct device *dev)
3630 {
3631 	const char *dev_id = dev ? dev_name(dev) : NULL;
3632 	struct gpiod_lookup_table *table;
3633 
3634 	mutex_lock(&gpio_lookup_lock);
3635 
3636 	list_for_each_entry(table, &gpio_lookup_list, list) {
3637 		if (table->dev_id && dev_id) {
3638 			/*
3639 			 * Valid strings on both ends, must be identical to have
3640 			 * a match
3641 			 */
3642 			if (!strcmp(table->dev_id, dev_id))
3643 				goto found;
3644 		} else {
3645 			/*
3646 			 * One of the pointers is NULL, so both must be to have
3647 			 * a match
3648 			 */
3649 			if (dev_id == table->dev_id)
3650 				goto found;
3651 		}
3652 	}
3653 	table = NULL;
3654 
3655 found:
3656 	mutex_unlock(&gpio_lookup_lock);
3657 	return table;
3658 }
3659 
3660 static struct gpio_desc *gpiod_find(struct device *dev, const char *con_id,
3661 				    unsigned int idx, unsigned long *flags)
3662 {
3663 	struct gpio_desc *desc = ERR_PTR(-ENOENT);
3664 	struct gpiod_lookup_table *table;
3665 	struct gpiod_lookup *p;
3666 
3667 	table = gpiod_find_lookup_table(dev);
3668 	if (!table)
3669 		return desc;
3670 
3671 	for (p = &table->table[0]; p->key; p++) {
3672 		struct gpio_chip *gc;
3673 
3674 		/* idx must always match exactly */
3675 		if (p->idx != idx)
3676 			continue;
3677 
3678 		/* If the lookup entry has a con_id, require exact match */
3679 		if (p->con_id && (!con_id || strcmp(p->con_id, con_id)))
3680 			continue;
3681 
3682 		if (p->chip_hwnum == U16_MAX) {
3683 			desc = gpio_name_to_desc(p->key);
3684 			if (desc) {
3685 				*flags = p->flags;
3686 				return desc;
3687 			}
3688 
3689 			dev_warn(dev, "cannot find GPIO line %s, deferring\n",
3690 				 p->key);
3691 			return ERR_PTR(-EPROBE_DEFER);
3692 		}
3693 
3694 		gc = find_chip_by_name(p->key);
3695 
3696 		if (!gc) {
3697 			/*
3698 			 * As the lookup table indicates a chip with
3699 			 * p->key should exist, assume it may
3700 			 * still appear later and let the interested
3701 			 * consumer be probed again or let the Deferred
3702 			 * Probe infrastructure handle the error.
3703 			 */
3704 			dev_warn(dev, "cannot find GPIO chip %s, deferring\n",
3705 				 p->key);
3706 			return ERR_PTR(-EPROBE_DEFER);
3707 		}
3708 
3709 		if (gc->ngpio <= p->chip_hwnum) {
3710 			dev_err(dev,
3711 				"requested GPIO %u (%u) is out of range [0..%u] for chip %s\n",
3712 				idx, p->chip_hwnum, gc->ngpio - 1,
3713 				gc->label);
3714 			return ERR_PTR(-EINVAL);
3715 		}
3716 
3717 		desc = gpiochip_get_desc(gc, p->chip_hwnum);
3718 		*flags = p->flags;
3719 
3720 		return desc;
3721 	}
3722 
3723 	return desc;
3724 }
3725 
3726 static int platform_gpio_count(struct device *dev, const char *con_id)
3727 {
3728 	struct gpiod_lookup_table *table;
3729 	struct gpiod_lookup *p;
3730 	unsigned int count = 0;
3731 
3732 	table = gpiod_find_lookup_table(dev);
3733 	if (!table)
3734 		return -ENOENT;
3735 
3736 	for (p = &table->table[0]; p->key; p++) {
3737 		if ((con_id && p->con_id && !strcmp(con_id, p->con_id)) ||
3738 		    (!con_id && !p->con_id))
3739 			count++;
3740 	}
3741 	if (!count)
3742 		return -ENOENT;
3743 
3744 	return count;
3745 }
3746 
3747 /**
3748  * fwnode_gpiod_get_index - obtain a GPIO from firmware node
3749  * @fwnode:	handle of the firmware node
3750  * @con_id:	function within the GPIO consumer
3751  * @index:	index of the GPIO to obtain for the consumer
3752  * @flags:	GPIO initialization flags
3753  * @label:	label to attach to the requested GPIO
3754  *
3755  * This function can be used for drivers that get their configuration
3756  * from opaque firmware.
3757  *
3758  * The function properly finds the corresponding GPIO using whatever is the
3759  * underlying firmware interface and then makes sure that the GPIO
3760  * descriptor is requested before it is returned to the caller.
3761  *
3762  * Returns:
3763  * On successful request the GPIO pin is configured in accordance with
3764  * provided @flags.
3765  *
3766  * In case of error an ERR_PTR() is returned.
3767  */
3768 struct gpio_desc *fwnode_gpiod_get_index(struct fwnode_handle *fwnode,
3769 					 const char *con_id, int index,
3770 					 enum gpiod_flags flags,
3771 					 const char *label)
3772 {
3773 	struct gpio_desc *desc;
3774 	char prop_name[32]; /* 32 is max size of property name */
3775 	unsigned int i;
3776 
3777 	for (i = 0; i < ARRAY_SIZE(gpio_suffixes); i++) {
3778 		if (con_id)
3779 			snprintf(prop_name, sizeof(prop_name), "%s-%s",
3780 					    con_id, gpio_suffixes[i]);
3781 		else
3782 			snprintf(prop_name, sizeof(prop_name), "%s",
3783 					    gpio_suffixes[i]);
3784 
3785 		desc = fwnode_get_named_gpiod(fwnode, prop_name, index, flags,
3786 					      label);
3787 		if (!IS_ERR(desc) || (PTR_ERR(desc) != -ENOENT))
3788 			break;
3789 	}
3790 
3791 	return desc;
3792 }
3793 EXPORT_SYMBOL_GPL(fwnode_gpiod_get_index);
3794 
3795 /**
3796  * gpiod_count - return the number of GPIOs associated with a device / function
3797  *		or -ENOENT if no GPIO has been assigned to the requested function
3798  * @dev:	GPIO consumer, can be NULL for system-global GPIOs
3799  * @con_id:	function within the GPIO consumer
3800  */
3801 int gpiod_count(struct device *dev, const char *con_id)
3802 {
3803 	int count = -ENOENT;
3804 
3805 	if (IS_ENABLED(CONFIG_OF) && dev && dev->of_node)
3806 		count = of_gpio_get_count(dev, con_id);
3807 	else if (IS_ENABLED(CONFIG_ACPI) && dev && ACPI_HANDLE(dev))
3808 		count = acpi_gpio_count(dev, con_id);
3809 
3810 	if (count < 0)
3811 		count = platform_gpio_count(dev, con_id);
3812 
3813 	return count;
3814 }
3815 EXPORT_SYMBOL_GPL(gpiod_count);
3816 
3817 /**
3818  * gpiod_get - obtain a GPIO for a given GPIO function
3819  * @dev:	GPIO consumer, can be NULL for system-global GPIOs
3820  * @con_id:	function within the GPIO consumer
3821  * @flags:	optional GPIO initialization flags
3822  *
3823  * Return the GPIO descriptor corresponding to the function con_id of device
3824  * dev, -ENOENT if no GPIO has been assigned to the requested function, or
3825  * another IS_ERR() code if an error occurred while trying to acquire the GPIO.
3826  */
3827 struct gpio_desc *__must_check gpiod_get(struct device *dev, const char *con_id,
3828 					 enum gpiod_flags flags)
3829 {
3830 	return gpiod_get_index(dev, con_id, 0, flags);
3831 }
3832 EXPORT_SYMBOL_GPL(gpiod_get);
3833 
3834 /**
3835  * gpiod_get_optional - obtain an optional GPIO for a given GPIO function
3836  * @dev: GPIO consumer, can be NULL for system-global GPIOs
3837  * @con_id: function within the GPIO consumer
3838  * @flags: optional GPIO initialization flags
3839  *
3840  * This is equivalent to gpiod_get(), except that when no GPIO was assigned to
3841  * the requested function it will return NULL. This is convenient for drivers
3842  * that need to handle optional GPIOs.
3843  */
3844 struct gpio_desc *__must_check gpiod_get_optional(struct device *dev,
3845 						  const char *con_id,
3846 						  enum gpiod_flags flags)
3847 {
3848 	return gpiod_get_index_optional(dev, con_id, 0, flags);
3849 }
3850 EXPORT_SYMBOL_GPL(gpiod_get_optional);
3851 
3852 
3853 /**
3854  * gpiod_configure_flags - helper function to configure a given GPIO
3855  * @desc:	gpio whose value will be assigned
3856  * @con_id:	function within the GPIO consumer
3857  * @lflags:	bitmask of gpio_lookup_flags GPIO_* values - returned from
3858  *		of_find_gpio() or of_get_gpio_hog()
3859  * @dflags:	gpiod_flags - optional GPIO initialization flags
3860  *
3861  * Return 0 on success, -ENOENT if no GPIO has been assigned to the
3862  * requested function and/or index, or another IS_ERR() code if an error
3863  * occurred while trying to acquire the GPIO.
3864  */
3865 int gpiod_configure_flags(struct gpio_desc *desc, const char *con_id,
3866 		unsigned long lflags, enum gpiod_flags dflags)
3867 {
3868 	int ret;
3869 
3870 	if (lflags & GPIO_ACTIVE_LOW)
3871 		set_bit(FLAG_ACTIVE_LOW, &desc->flags);
3872 
3873 	if (lflags & GPIO_OPEN_DRAIN)
3874 		set_bit(FLAG_OPEN_DRAIN, &desc->flags);
3875 	else if (dflags & GPIOD_FLAGS_BIT_OPEN_DRAIN) {
3876 		/*
3877 		 * This enforces open drain mode from the consumer side.
3878 		 * This is necessary for some busses like I2C, but the lookup
3879 		 * should *REALLY* have specified them as open drain in the
3880 		 * first place, so print a little warning here.
3881 		 */
3882 		set_bit(FLAG_OPEN_DRAIN, &desc->flags);
3883 		gpiod_warn(desc,
3884 			   "enforced open drain please flag it properly in DT/ACPI DSDT/board file\n");
3885 	}
3886 
3887 	if (lflags & GPIO_OPEN_SOURCE)
3888 		set_bit(FLAG_OPEN_SOURCE, &desc->flags);
3889 
3890 	if ((lflags & GPIO_PULL_UP) && (lflags & GPIO_PULL_DOWN)) {
3891 		gpiod_err(desc,
3892 			  "both pull-up and pull-down enabled, invalid configuration\n");
3893 		return -EINVAL;
3894 	}
3895 
3896 	if (lflags & GPIO_PULL_UP)
3897 		set_bit(FLAG_PULL_UP, &desc->flags);
3898 	else if (lflags & GPIO_PULL_DOWN)
3899 		set_bit(FLAG_PULL_DOWN, &desc->flags);
3900 
3901 	ret = gpiod_set_transitory(desc, (lflags & GPIO_TRANSITORY));
3902 	if (ret < 0)
3903 		return ret;
3904 
3905 	/* No particular flag request, return here... */
3906 	if (!(dflags & GPIOD_FLAGS_BIT_DIR_SET)) {
3907 		gpiod_dbg(desc, "no flags found for %s\n", con_id);
3908 		return 0;
3909 	}
3910 
3911 	/* Process flags */
3912 	if (dflags & GPIOD_FLAGS_BIT_DIR_OUT)
3913 		ret = gpiod_direction_output(desc,
3914 				!!(dflags & GPIOD_FLAGS_BIT_DIR_VAL));
3915 	else
3916 		ret = gpiod_direction_input(desc);
3917 
3918 	return ret;
3919 }
3920 
3921 /**
3922  * gpiod_get_index - obtain a GPIO from a multi-index GPIO function
3923  * @dev:	GPIO consumer, can be NULL for system-global GPIOs
3924  * @con_id:	function within the GPIO consumer
3925  * @idx:	index of the GPIO to obtain in the consumer
3926  * @flags:	optional GPIO initialization flags
3927  *
3928  * This variant of gpiod_get() allows to access GPIOs other than the first
3929  * defined one for functions that define several GPIOs.
3930  *
3931  * Return a valid GPIO descriptor, -ENOENT if no GPIO has been assigned to the
3932  * requested function and/or index, or another IS_ERR() code if an error
3933  * occurred while trying to acquire the GPIO.
3934  */
3935 struct gpio_desc *__must_check gpiod_get_index(struct device *dev,
3936 					       const char *con_id,
3937 					       unsigned int idx,
3938 					       enum gpiod_flags flags)
3939 {
3940 	unsigned long lookupflags = GPIO_LOOKUP_FLAGS_DEFAULT;
3941 	struct gpio_desc *desc = NULL;
3942 	int ret;
3943 	/* Maybe we have a device name, maybe not */
3944 	const char *devname = dev ? dev_name(dev) : "?";
3945 
3946 	dev_dbg(dev, "GPIO lookup for consumer %s\n", con_id);
3947 
3948 	if (dev) {
3949 		/* Using device tree? */
3950 		if (IS_ENABLED(CONFIG_OF) && dev->of_node) {
3951 			dev_dbg(dev, "using device tree for GPIO lookup\n");
3952 			desc = of_find_gpio(dev, con_id, idx, &lookupflags);
3953 		} else if (ACPI_COMPANION(dev)) {
3954 			dev_dbg(dev, "using ACPI for GPIO lookup\n");
3955 			desc = acpi_find_gpio(dev, con_id, idx, &flags, &lookupflags);
3956 		}
3957 	}
3958 
3959 	/*
3960 	 * Either we are not using DT or ACPI, or their lookup did not return
3961 	 * a result. In that case, use platform lookup as a fallback.
3962 	 */
3963 	if (!desc || desc == ERR_PTR(-ENOENT)) {
3964 		dev_dbg(dev, "using lookup tables for GPIO lookup\n");
3965 		desc = gpiod_find(dev, con_id, idx, &lookupflags);
3966 	}
3967 
3968 	if (IS_ERR(desc)) {
3969 		dev_dbg(dev, "No GPIO consumer %s found\n", con_id);
3970 		return desc;
3971 	}
3972 
3973 	/*
3974 	 * If a connection label was passed use that, else attempt to use
3975 	 * the device name as label
3976 	 */
3977 	ret = gpiod_request(desc, con_id ? con_id : devname);
3978 	if (ret < 0) {
3979 		if (ret == -EBUSY && flags & GPIOD_FLAGS_BIT_NONEXCLUSIVE) {
3980 			/*
3981 			 * This happens when there are several consumers for
3982 			 * the same GPIO line: we just return here without
3983 			 * further initialization. It is a bit if a hack.
3984 			 * This is necessary to support fixed regulators.
3985 			 *
3986 			 * FIXME: Make this more sane and safe.
3987 			 */
3988 			dev_info(dev, "nonexclusive access to GPIO for %s\n",
3989 				 con_id ? con_id : devname);
3990 			return desc;
3991 		} else {
3992 			return ERR_PTR(ret);
3993 		}
3994 	}
3995 
3996 	ret = gpiod_configure_flags(desc, con_id, lookupflags, flags);
3997 	if (ret < 0) {
3998 		dev_dbg(dev, "setup of GPIO %s failed\n", con_id);
3999 		gpiod_put(desc);
4000 		return ERR_PTR(ret);
4001 	}
4002 
4003 	blocking_notifier_call_chain(&desc->gdev->notifier,
4004 				     GPIOLINE_CHANGED_REQUESTED, desc);
4005 
4006 	return desc;
4007 }
4008 EXPORT_SYMBOL_GPL(gpiod_get_index);
4009 
4010 /**
4011  * fwnode_get_named_gpiod - obtain a GPIO from firmware node
4012  * @fwnode:	handle of the firmware node
4013  * @propname:	name of the firmware property representing the GPIO
4014  * @index:	index of the GPIO to obtain for the consumer
4015  * @dflags:	GPIO initialization flags
4016  * @label:	label to attach to the requested GPIO
4017  *
4018  * This function can be used for drivers that get their configuration
4019  * from opaque firmware.
4020  *
4021  * The function properly finds the corresponding GPIO using whatever is the
4022  * underlying firmware interface and then makes sure that the GPIO
4023  * descriptor is requested before it is returned to the caller.
4024  *
4025  * Returns:
4026  * On successful request the GPIO pin is configured in accordance with
4027  * provided @dflags.
4028  *
4029  * In case of error an ERR_PTR() is returned.
4030  */
4031 struct gpio_desc *fwnode_get_named_gpiod(struct fwnode_handle *fwnode,
4032 					 const char *propname, int index,
4033 					 enum gpiod_flags dflags,
4034 					 const char *label)
4035 {
4036 	unsigned long lflags = GPIO_LOOKUP_FLAGS_DEFAULT;
4037 	struct gpio_desc *desc = ERR_PTR(-ENODEV);
4038 	int ret;
4039 
4040 	if (!fwnode)
4041 		return ERR_PTR(-EINVAL);
4042 
4043 	if (is_of_node(fwnode)) {
4044 		desc = gpiod_get_from_of_node(to_of_node(fwnode),
4045 					      propname, index,
4046 					      dflags,
4047 					      label);
4048 		return desc;
4049 	} else if (is_acpi_node(fwnode)) {
4050 		struct acpi_gpio_info info;
4051 
4052 		desc = acpi_node_get_gpiod(fwnode, propname, index, &info);
4053 		if (IS_ERR(desc))
4054 			return desc;
4055 
4056 		acpi_gpio_update_gpiod_flags(&dflags, &info);
4057 		acpi_gpio_update_gpiod_lookup_flags(&lflags, &info);
4058 	}
4059 
4060 	/* Currently only ACPI takes this path */
4061 	ret = gpiod_request(desc, label);
4062 	if (ret)
4063 		return ERR_PTR(ret);
4064 
4065 	ret = gpiod_configure_flags(desc, propname, lflags, dflags);
4066 	if (ret < 0) {
4067 		gpiod_put(desc);
4068 		return ERR_PTR(ret);
4069 	}
4070 
4071 	blocking_notifier_call_chain(&desc->gdev->notifier,
4072 				     GPIOLINE_CHANGED_REQUESTED, desc);
4073 
4074 	return desc;
4075 }
4076 EXPORT_SYMBOL_GPL(fwnode_get_named_gpiod);
4077 
4078 /**
4079  * gpiod_get_index_optional - obtain an optional GPIO from a multi-index GPIO
4080  *                            function
4081  * @dev: GPIO consumer, can be NULL for system-global GPIOs
4082  * @con_id: function within the GPIO consumer
4083  * @index: index of the GPIO to obtain in the consumer
4084  * @flags: optional GPIO initialization flags
4085  *
4086  * This is equivalent to gpiod_get_index(), except that when no GPIO with the
4087  * specified index was assigned to the requested function it will return NULL.
4088  * This is convenient for drivers that need to handle optional GPIOs.
4089  */
4090 struct gpio_desc *__must_check gpiod_get_index_optional(struct device *dev,
4091 							const char *con_id,
4092 							unsigned int index,
4093 							enum gpiod_flags flags)
4094 {
4095 	struct gpio_desc *desc;
4096 
4097 	desc = gpiod_get_index(dev, con_id, index, flags);
4098 	if (IS_ERR(desc)) {
4099 		if (PTR_ERR(desc) == -ENOENT)
4100 			return NULL;
4101 	}
4102 
4103 	return desc;
4104 }
4105 EXPORT_SYMBOL_GPL(gpiod_get_index_optional);
4106 
4107 /**
4108  * gpiod_hog - Hog the specified GPIO desc given the provided flags
4109  * @desc:	gpio whose value will be assigned
4110  * @name:	gpio line name
4111  * @lflags:	bitmask of gpio_lookup_flags GPIO_* values - returned from
4112  *		of_find_gpio() or of_get_gpio_hog()
4113  * @dflags:	gpiod_flags - optional GPIO initialization flags
4114  */
4115 int gpiod_hog(struct gpio_desc *desc, const char *name,
4116 	      unsigned long lflags, enum gpiod_flags dflags)
4117 {
4118 	struct gpio_chip *gc;
4119 	struct gpio_desc *local_desc;
4120 	int hwnum;
4121 	int ret;
4122 
4123 	gc = gpiod_to_chip(desc);
4124 	hwnum = gpio_chip_hwgpio(desc);
4125 
4126 	local_desc = gpiochip_request_own_desc(gc, hwnum, name,
4127 					       lflags, dflags);
4128 	if (IS_ERR(local_desc)) {
4129 		ret = PTR_ERR(local_desc);
4130 		pr_err("requesting hog GPIO %s (chip %s, offset %d) failed, %d\n",
4131 		       name, gc->label, hwnum, ret);
4132 		return ret;
4133 	}
4134 
4135 	/* Mark GPIO as hogged so it can be identified and removed later */
4136 	set_bit(FLAG_IS_HOGGED, &desc->flags);
4137 
4138 	gpiod_info(desc, "hogged as %s%s\n",
4139 		(dflags & GPIOD_FLAGS_BIT_DIR_OUT) ? "output" : "input",
4140 		(dflags & GPIOD_FLAGS_BIT_DIR_OUT) ?
4141 		  (dflags & GPIOD_FLAGS_BIT_DIR_VAL) ? "/high" : "/low" : "");
4142 
4143 	return 0;
4144 }
4145 
4146 /**
4147  * gpiochip_free_hogs - Scan gpio-controller chip and release GPIO hog
4148  * @gc:	gpio chip to act on
4149  */
4150 static void gpiochip_free_hogs(struct gpio_chip *gc)
4151 {
4152 	int id;
4153 
4154 	for (id = 0; id < gc->ngpio; id++) {
4155 		if (test_bit(FLAG_IS_HOGGED, &gc->gpiodev->descs[id].flags))
4156 			gpiochip_free_own_desc(&gc->gpiodev->descs[id]);
4157 	}
4158 }
4159 
4160 /**
4161  * gpiod_get_array - obtain multiple GPIOs from a multi-index GPIO function
4162  * @dev:	GPIO consumer, can be NULL for system-global GPIOs
4163  * @con_id:	function within the GPIO consumer
4164  * @flags:	optional GPIO initialization flags
4165  *
4166  * This function acquires all the GPIOs defined under a given function.
4167  *
4168  * Return a struct gpio_descs containing an array of descriptors, -ENOENT if
4169  * no GPIO has been assigned to the requested function, or another IS_ERR()
4170  * code if an error occurred while trying to acquire the GPIOs.
4171  */
4172 struct gpio_descs *__must_check gpiod_get_array(struct device *dev,
4173 						const char *con_id,
4174 						enum gpiod_flags flags)
4175 {
4176 	struct gpio_desc *desc;
4177 	struct gpio_descs *descs;
4178 	struct gpio_array *array_info = NULL;
4179 	struct gpio_chip *gc;
4180 	int count, bitmap_size;
4181 
4182 	count = gpiod_count(dev, con_id);
4183 	if (count < 0)
4184 		return ERR_PTR(count);
4185 
4186 	descs = kzalloc(struct_size(descs, desc, count), GFP_KERNEL);
4187 	if (!descs)
4188 		return ERR_PTR(-ENOMEM);
4189 
4190 	for (descs->ndescs = 0; descs->ndescs < count; ) {
4191 		desc = gpiod_get_index(dev, con_id, descs->ndescs, flags);
4192 		if (IS_ERR(desc)) {
4193 			gpiod_put_array(descs);
4194 			return ERR_CAST(desc);
4195 		}
4196 
4197 		descs->desc[descs->ndescs] = desc;
4198 
4199 		gc = gpiod_to_chip(desc);
4200 		/*
4201 		 * If pin hardware number of array member 0 is also 0, select
4202 		 * its chip as a candidate for fast bitmap processing path.
4203 		 */
4204 		if (descs->ndescs == 0 && gpio_chip_hwgpio(desc) == 0) {
4205 			struct gpio_descs *array;
4206 
4207 			bitmap_size = BITS_TO_LONGS(gc->ngpio > count ?
4208 						    gc->ngpio : count);
4209 
4210 			array = kzalloc(struct_size(descs, desc, count) +
4211 					struct_size(array_info, invert_mask,
4212 					3 * bitmap_size), GFP_KERNEL);
4213 			if (!array) {
4214 				gpiod_put_array(descs);
4215 				return ERR_PTR(-ENOMEM);
4216 			}
4217 
4218 			memcpy(array, descs,
4219 			       struct_size(descs, desc, descs->ndescs + 1));
4220 			kfree(descs);
4221 
4222 			descs = array;
4223 			array_info = (void *)(descs->desc + count);
4224 			array_info->get_mask = array_info->invert_mask +
4225 						  bitmap_size;
4226 			array_info->set_mask = array_info->get_mask +
4227 						  bitmap_size;
4228 
4229 			array_info->desc = descs->desc;
4230 			array_info->size = count;
4231 			array_info->chip = gc;
4232 			bitmap_set(array_info->get_mask, descs->ndescs,
4233 				   count - descs->ndescs);
4234 			bitmap_set(array_info->set_mask, descs->ndescs,
4235 				   count - descs->ndescs);
4236 			descs->info = array_info;
4237 		}
4238 		/* Unmark array members which don't belong to the 'fast' chip */
4239 		if (array_info && array_info->chip != gc) {
4240 			__clear_bit(descs->ndescs, array_info->get_mask);
4241 			__clear_bit(descs->ndescs, array_info->set_mask);
4242 		}
4243 		/*
4244 		 * Detect array members which belong to the 'fast' chip
4245 		 * but their pins are not in hardware order.
4246 		 */
4247 		else if (array_info &&
4248 			   gpio_chip_hwgpio(desc) != descs->ndescs) {
4249 			/*
4250 			 * Don't use fast path if all array members processed so
4251 			 * far belong to the same chip as this one but its pin
4252 			 * hardware number is different from its array index.
4253 			 */
4254 			if (bitmap_full(array_info->get_mask, descs->ndescs)) {
4255 				array_info = NULL;
4256 			} else {
4257 				__clear_bit(descs->ndescs,
4258 					    array_info->get_mask);
4259 				__clear_bit(descs->ndescs,
4260 					    array_info->set_mask);
4261 			}
4262 		} else if (array_info) {
4263 			/* Exclude open drain or open source from fast output */
4264 			if (gpiochip_line_is_open_drain(gc, descs->ndescs) ||
4265 			    gpiochip_line_is_open_source(gc, descs->ndescs))
4266 				__clear_bit(descs->ndescs,
4267 					    array_info->set_mask);
4268 			/* Identify 'fast' pins which require invertion */
4269 			if (gpiod_is_active_low(desc))
4270 				__set_bit(descs->ndescs,
4271 					  array_info->invert_mask);
4272 		}
4273 
4274 		descs->ndescs++;
4275 	}
4276 	if (array_info)
4277 		dev_dbg(dev,
4278 			"GPIO array info: chip=%s, size=%d, get_mask=%lx, set_mask=%lx, invert_mask=%lx\n",
4279 			array_info->chip->label, array_info->size,
4280 			*array_info->get_mask, *array_info->set_mask,
4281 			*array_info->invert_mask);
4282 	return descs;
4283 }
4284 EXPORT_SYMBOL_GPL(gpiod_get_array);
4285 
4286 /**
4287  * gpiod_get_array_optional - obtain multiple GPIOs from a multi-index GPIO
4288  *                            function
4289  * @dev:	GPIO consumer, can be NULL for system-global GPIOs
4290  * @con_id:	function within the GPIO consumer
4291  * @flags:	optional GPIO initialization flags
4292  *
4293  * This is equivalent to gpiod_get_array(), except that when no GPIO was
4294  * assigned to the requested function it will return NULL.
4295  */
4296 struct gpio_descs *__must_check gpiod_get_array_optional(struct device *dev,
4297 							const char *con_id,
4298 							enum gpiod_flags flags)
4299 {
4300 	struct gpio_descs *descs;
4301 
4302 	descs = gpiod_get_array(dev, con_id, flags);
4303 	if (PTR_ERR(descs) == -ENOENT)
4304 		return NULL;
4305 
4306 	return descs;
4307 }
4308 EXPORT_SYMBOL_GPL(gpiod_get_array_optional);
4309 
4310 /**
4311  * gpiod_put - dispose of a GPIO descriptor
4312  * @desc:	GPIO descriptor to dispose of
4313  *
4314  * No descriptor can be used after gpiod_put() has been called on it.
4315  */
4316 void gpiod_put(struct gpio_desc *desc)
4317 {
4318 	if (desc)
4319 		gpiod_free(desc);
4320 }
4321 EXPORT_SYMBOL_GPL(gpiod_put);
4322 
4323 /**
4324  * gpiod_put_array - dispose of multiple GPIO descriptors
4325  * @descs:	struct gpio_descs containing an array of descriptors
4326  */
4327 void gpiod_put_array(struct gpio_descs *descs)
4328 {
4329 	unsigned int i;
4330 
4331 	for (i = 0; i < descs->ndescs; i++)
4332 		gpiod_put(descs->desc[i]);
4333 
4334 	kfree(descs);
4335 }
4336 EXPORT_SYMBOL_GPL(gpiod_put_array);
4337 
4338 static int __init gpiolib_dev_init(void)
4339 {
4340 	int ret;
4341 
4342 	/* Register GPIO sysfs bus */
4343 	ret = bus_register(&gpio_bus_type);
4344 	if (ret < 0) {
4345 		pr_err("gpiolib: could not register GPIO bus type\n");
4346 		return ret;
4347 	}
4348 
4349 	ret = alloc_chrdev_region(&gpio_devt, 0, GPIO_DEV_MAX, GPIOCHIP_NAME);
4350 	if (ret < 0) {
4351 		pr_err("gpiolib: failed to allocate char dev region\n");
4352 		bus_unregister(&gpio_bus_type);
4353 		return ret;
4354 	}
4355 
4356 	gpiolib_initialized = true;
4357 	gpiochip_setup_devs();
4358 
4359 #if IS_ENABLED(CONFIG_OF_DYNAMIC) && IS_ENABLED(CONFIG_OF_GPIO)
4360 	WARN_ON(of_reconfig_notifier_register(&gpio_of_notifier));
4361 #endif /* CONFIG_OF_DYNAMIC && CONFIG_OF_GPIO */
4362 
4363 	return ret;
4364 }
4365 core_initcall(gpiolib_dev_init);
4366 
4367 #ifdef CONFIG_DEBUG_FS
4368 
4369 static void gpiolib_dbg_show(struct seq_file *s, struct gpio_device *gdev)
4370 {
4371 	unsigned		i;
4372 	struct gpio_chip	*gc = gdev->chip;
4373 	unsigned		gpio = gdev->base;
4374 	struct gpio_desc	*gdesc = &gdev->descs[0];
4375 	bool			is_out;
4376 	bool			is_irq;
4377 	bool			active_low;
4378 
4379 	for (i = 0; i < gdev->ngpio; i++, gpio++, gdesc++) {
4380 		if (!test_bit(FLAG_REQUESTED, &gdesc->flags)) {
4381 			if (gdesc->name) {
4382 				seq_printf(s, " gpio-%-3d (%-20.20s)\n",
4383 					   gpio, gdesc->name);
4384 			}
4385 			continue;
4386 		}
4387 
4388 		gpiod_get_direction(gdesc);
4389 		is_out = test_bit(FLAG_IS_OUT, &gdesc->flags);
4390 		is_irq = test_bit(FLAG_USED_AS_IRQ, &gdesc->flags);
4391 		active_low = test_bit(FLAG_ACTIVE_LOW, &gdesc->flags);
4392 		seq_printf(s, " gpio-%-3d (%-20.20s|%-20.20s) %s %s %s%s",
4393 			gpio, gdesc->name ? gdesc->name : "", gdesc->label,
4394 			is_out ? "out" : "in ",
4395 			gc->get ? (gc->get(gc, i) ? "hi" : "lo") : "?  ",
4396 			is_irq ? "IRQ " : "",
4397 			active_low ? "ACTIVE LOW" : "");
4398 		seq_printf(s, "\n");
4399 	}
4400 }
4401 
4402 static void *gpiolib_seq_start(struct seq_file *s, loff_t *pos)
4403 {
4404 	unsigned long flags;
4405 	struct gpio_device *gdev = NULL;
4406 	loff_t index = *pos;
4407 
4408 	s->private = "";
4409 
4410 	spin_lock_irqsave(&gpio_lock, flags);
4411 	list_for_each_entry(gdev, &gpio_devices, list)
4412 		if (index-- == 0) {
4413 			spin_unlock_irqrestore(&gpio_lock, flags);
4414 			return gdev;
4415 		}
4416 	spin_unlock_irqrestore(&gpio_lock, flags);
4417 
4418 	return NULL;
4419 }
4420 
4421 static void *gpiolib_seq_next(struct seq_file *s, void *v, loff_t *pos)
4422 {
4423 	unsigned long flags;
4424 	struct gpio_device *gdev = v;
4425 	void *ret = NULL;
4426 
4427 	spin_lock_irqsave(&gpio_lock, flags);
4428 	if (list_is_last(&gdev->list, &gpio_devices))
4429 		ret = NULL;
4430 	else
4431 		ret = list_entry(gdev->list.next, struct gpio_device, list);
4432 	spin_unlock_irqrestore(&gpio_lock, flags);
4433 
4434 	s->private = "\n";
4435 	++*pos;
4436 
4437 	return ret;
4438 }
4439 
4440 static void gpiolib_seq_stop(struct seq_file *s, void *v)
4441 {
4442 }
4443 
4444 static int gpiolib_seq_show(struct seq_file *s, void *v)
4445 {
4446 	struct gpio_device *gdev = v;
4447 	struct gpio_chip *gc = gdev->chip;
4448 	struct device *parent;
4449 
4450 	if (!gc) {
4451 		seq_printf(s, "%s%s: (dangling chip)", (char *)s->private,
4452 			   dev_name(&gdev->dev));
4453 		return 0;
4454 	}
4455 
4456 	seq_printf(s, "%s%s: GPIOs %d-%d", (char *)s->private,
4457 		   dev_name(&gdev->dev),
4458 		   gdev->base, gdev->base + gdev->ngpio - 1);
4459 	parent = gc->parent;
4460 	if (parent)
4461 		seq_printf(s, ", parent: %s/%s",
4462 			   parent->bus ? parent->bus->name : "no-bus",
4463 			   dev_name(parent));
4464 	if (gc->label)
4465 		seq_printf(s, ", %s", gc->label);
4466 	if (gc->can_sleep)
4467 		seq_printf(s, ", can sleep");
4468 	seq_printf(s, ":\n");
4469 
4470 	if (gc->dbg_show)
4471 		gc->dbg_show(s, gc);
4472 	else
4473 		gpiolib_dbg_show(s, gdev);
4474 
4475 	return 0;
4476 }
4477 
4478 static const struct seq_operations gpiolib_sops = {
4479 	.start = gpiolib_seq_start,
4480 	.next = gpiolib_seq_next,
4481 	.stop = gpiolib_seq_stop,
4482 	.show = gpiolib_seq_show,
4483 };
4484 DEFINE_SEQ_ATTRIBUTE(gpiolib);
4485 
4486 static int __init gpiolib_debugfs_init(void)
4487 {
4488 	/* /sys/kernel/debug/gpio */
4489 	debugfs_create_file("gpio", 0444, NULL, NULL, &gpiolib_fops);
4490 	return 0;
4491 }
4492 subsys_initcall(gpiolib_debugfs_init);
4493 
4494 #endif	/* DEBUG_FS */
4495