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>
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>
21 #include <linux/compat.h>
22 #include <linux/file.h>
23 #include <uapi/linux/gpio.h>
26 #include "gpiolib-of.h"
27 #include "gpiolib-acpi.h"
28 #include "gpiolib-cdev.h"
29 #include "gpiolib-sysfs.h"
31 #define CREATE_TRACE_POINTS
32 #include <trace/events/gpio.h>
34 /* Implementation infrastructure for GPIO interfaces.
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.
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.
46 * Otherwise, minimize overhead in what may be bitbanging codepaths.
49 #define extra_checks 1
51 #define extra_checks 0
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 = {
63 * Number of GPIOs to use for the fast path in set array
65 #define FASTPATH_NGPIO CONFIG_GPIOLIB_FASTPATH_LIMIT
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.
71 DEFINE_SPINLOCK(gpio_lock);
73 static DEFINE_MUTEX(gpio_lookup_lock);
74 static LIST_HEAD(gpio_lookup_list);
75 LIST_HEAD(gpio_devices);
77 static DEFINE_MUTEX(gpio_machine_hogs_mutex);
78 static LIST_HEAD(gpio_machine_hogs);
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);
89 static bool gpiolib_initialized;
91 static inline void desc_set_label(struct gpio_desc *d, const char *label)
97 * gpio_to_desc - Convert a GPIO number to its descriptor
98 * @gpio: global GPIO number
101 * The GPIO descriptor associated with the given GPIO, or %NULL if no GPIO
102 * with the given number exists in the system.
104 struct gpio_desc *gpio_to_desc(unsigned gpio)
106 struct gpio_device *gdev;
109 spin_lock_irqsave(&gpio_lock, flags);
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];
119 spin_unlock_irqrestore(&gpio_lock, flags);
121 if (!gpio_is_valid(gpio))
122 WARN(1, "invalid GPIO %d\n", gpio);
126 EXPORT_SYMBOL_GPL(gpio_to_desc);
129 * gpiochip_get_desc - get the GPIO descriptor corresponding to the given
130 * hardware number for this chip
132 * @hwnum: hardware number of the GPIO for this chip
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.
138 struct gpio_desc *gpiochip_get_desc(struct gpio_chip *gc,
141 struct gpio_device *gdev = gc->gpiodev;
143 if (hwnum >= gdev->ngpio)
144 return ERR_PTR(-EINVAL);
146 return &gdev->descs[hwnum];
148 EXPORT_SYMBOL_GPL(gpiochip_get_desc);
151 * desc_to_gpio - convert a GPIO descriptor to the integer namespace
152 * @desc: GPIO descriptor
154 * This should disappear in the future but is needed since we still
155 * use GPIO numbers for error messages and sysfs nodes.
158 * The global GPIO number for the GPIO specified by its descriptor.
160 int desc_to_gpio(const struct gpio_desc *desc)
162 return desc->gdev->base + (desc - &desc->gdev->descs[0]);
164 EXPORT_SYMBOL_GPL(desc_to_gpio);
168 * gpiod_to_chip - Return the GPIO chip to which a GPIO descriptor belongs
169 * @desc: descriptor to return the chip of
171 struct gpio_chip *gpiod_to_chip(const struct gpio_desc *desc)
173 if (!desc || !desc->gdev)
175 return desc->gdev->chip;
177 EXPORT_SYMBOL_GPL(gpiod_to_chip);
179 /* dynamic allocation of GPIOs, e.g. on a hotplugged device */
180 static int gpiochip_find_base(int ngpio)
182 struct gpio_device *gdev;
183 int base = ARCH_NR_GPIOS - ngpio;
185 list_for_each_entry_reverse(gdev, &gpio_devices, list) {
186 /* found a free space? */
187 if (gdev->base + gdev->ngpio <= base)
190 /* nope, check the space right before the chip */
191 base = gdev->base - ngpio;
194 if (gpio_is_valid(base)) {
195 pr_debug("%s: found new base at %d\n", __func__, base);
198 pr_err("%s: cannot find free range\n", __func__);
204 * gpiod_get_direction - return the current direction of a GPIO
205 * @desc: GPIO to get the direction of
207 * Returns 0 for output, 1 for input, or an error code in case of error.
209 * This function may sleep if gpiod_cansleep() is true.
211 int gpiod_get_direction(struct gpio_desc *desc)
213 struct gpio_chip *gc;
217 gc = gpiod_to_chip(desc);
218 offset = gpio_chip_hwgpio(desc);
221 * Open drain emulation using input mode may incorrectly report
222 * input here, fix that up.
224 if (test_bit(FLAG_OPEN_DRAIN, &desc->flags) &&
225 test_bit(FLAG_IS_OUT, &desc->flags))
228 if (!gc->get_direction)
231 ret = gc->get_direction(gc, offset);
235 /* GPIOF_DIR_IN or other positive, otherwise GPIOF_DIR_OUT */
239 assign_bit(FLAG_IS_OUT, &desc->flags, !ret);
243 EXPORT_SYMBOL_GPL(gpiod_get_direction);
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.
249 * Return -EBUSY if the new chip overlaps with some other chip's integer
252 static int gpiodev_add_to_list(struct gpio_device *gdev)
254 struct gpio_device *prev, *next;
256 if (list_empty(&gpio_devices)) {
257 /* initial entry in list */
258 list_add_tail(&gdev->list, &gpio_devices);
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);
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);
276 list_for_each_entry_safe(prev, next, &gpio_devices, list) {
277 /* at the end of the list */
278 if (&next->list == &gpio_devices)
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);
289 dev_err(&gdev->dev, "GPIO integer space overlap, cannot add chip\n");
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.
299 static struct gpio_desc *gpio_name_to_desc(const char * const name)
301 struct gpio_device *gdev;
307 spin_lock_irqsave(&gpio_lock, flags);
309 list_for_each_entry(gdev, &gpio_devices, list) {
312 for (i = 0; i != gdev->ngpio; ++i) {
313 struct gpio_desc *desc = &gdev->descs[i];
318 if (!strcmp(desc->name, name)) {
319 spin_unlock_irqrestore(&gpio_lock, flags);
325 spin_unlock_irqrestore(&gpio_lock, flags);
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.
335 * 1. Non-unique names are still accepted,
336 * 2. Name collisions within the same GPIO chip are not reported.
338 static int gpiochip_set_desc_names(struct gpio_chip *gc)
340 struct gpio_device *gdev = gc->gpiodev;
346 /* First check all names if they are unique */
347 for (i = 0; i != gc->ngpio; ++i) {
348 struct gpio_desc *gpio;
350 gpio = gpio_name_to_desc(gc->names[i]);
353 "Detected name collision for GPIO name '%s'\n",
357 /* Then add all names to the GPIO descriptors */
358 for (i = 0; i != gc->ngpio; ++i)
359 gdev->descs[i].name = gc->names[i];
364 static unsigned long *gpiochip_allocate_mask(struct gpio_chip *gc)
368 p = bitmap_alloc(gc->ngpio, GFP_KERNEL);
372 /* Assume by default all GPIOs are valid */
373 bitmap_fill(p, gc->ngpio);
378 static int gpiochip_alloc_valid_mask(struct gpio_chip *gc)
380 if (!(of_gpio_need_valid_mask(gc) || gc->init_valid_mask))
383 gc->valid_mask = gpiochip_allocate_mask(gc);
390 static int gpiochip_init_valid_mask(struct gpio_chip *gc)
392 if (gc->init_valid_mask)
393 return gc->init_valid_mask(gc,
400 static void gpiochip_free_valid_mask(struct gpio_chip *gc)
402 bitmap_free(gc->valid_mask);
403 gc->valid_mask = NULL;
406 static int gpiochip_add_pin_ranges(struct gpio_chip *gc)
408 if (gc->add_pin_ranges)
409 return gc->add_pin_ranges(gc);
414 bool gpiochip_line_is_valid(const struct gpio_chip *gc,
417 /* No mask means all valid */
418 if (likely(!gc->valid_mask))
420 return test_bit(offset, gc->valid_mask);
422 EXPORT_SYMBOL_GPL(gpiochip_line_is_valid);
424 static void gpiodevice_release(struct device *dev)
426 struct gpio_device *gdev = dev_get_drvdata(dev);
428 list_del(&gdev->list);
429 ida_simple_remove(&gpio_ida, gdev->id);
430 kfree_const(gdev->label);
435 static int gpiochip_setup_dev(struct gpio_device *gdev)
439 ret = gpiolib_cdev_register(gdev, gpio_devt);
443 ret = gpiochip_sysfs_register(gdev);
445 goto err_remove_device;
447 /* From this point, the .release() function cleans up gpio_device */
448 gdev->dev.release = gpiodevice_release;
449 dev_dbg(&gdev->dev, "registered GPIOs %d to %d on %s\n", gdev->base,
450 gdev->base + gdev->ngpio - 1, gdev->chip->label ? : "generic");
455 gpiolib_cdev_unregister(gdev);
459 static void gpiochip_machine_hog(struct gpio_chip *gc, struct gpiod_hog *hog)
461 struct gpio_desc *desc;
464 desc = gpiochip_get_desc(gc, hog->chip_hwnum);
466 chip_err(gc, "%s: unable to get GPIO desc: %ld\n", __func__,
471 if (test_bit(FLAG_IS_HOGGED, &desc->flags))
474 rv = gpiod_hog(desc, hog->line_name, hog->lflags, hog->dflags);
476 gpiod_err(desc, "%s: unable to hog GPIO line (%s:%u): %d\n",
477 __func__, gc->label, hog->chip_hwnum, rv);
480 static void machine_gpiochip_add(struct gpio_chip *gc)
482 struct gpiod_hog *hog;
484 mutex_lock(&gpio_machine_hogs_mutex);
486 list_for_each_entry(hog, &gpio_machine_hogs, list) {
487 if (!strcmp(gc->label, hog->chip_label))
488 gpiochip_machine_hog(gc, hog);
491 mutex_unlock(&gpio_machine_hogs_mutex);
494 static void gpiochip_setup_devs(void)
496 struct gpio_device *gdev;
499 list_for_each_entry(gdev, &gpio_devices, list) {
500 ret = gpiochip_setup_dev(gdev);
503 "Failed to initialize gpio device (%d)\n", ret);
507 int gpiochip_add_data_with_key(struct gpio_chip *gc, void *data,
508 struct lock_class_key *lock_key,
509 struct lock_class_key *request_key)
515 struct gpio_device *gdev;
518 * First: allocate and populate the internal stat container, and
519 * set up the struct device.
521 gdev = kzalloc(sizeof(*gdev), GFP_KERNEL);
524 gdev->dev.bus = &gpio_bus_type;
528 gdev->dev.parent = gc->parent;
529 gdev->dev.of_node = gc->parent->of_node;
532 #ifdef CONFIG_OF_GPIO
533 /* If the gpiochip has an assigned OF node this takes precedence */
535 gdev->dev.of_node = gc->of_node;
537 gc->of_node = gdev->dev.of_node;
540 gdev->id = ida_simple_get(&gpio_ida, 0, 0, GFP_KERNEL);
545 dev_set_name(&gdev->dev, GPIOCHIP_NAME "%d", gdev->id);
546 device_initialize(&gdev->dev);
547 dev_set_drvdata(&gdev->dev, gdev);
548 if (gc->parent && gc->parent->driver)
549 gdev->owner = gc->parent->driver->owner;
551 /* TODO: remove chip->owner */
552 gdev->owner = gc->owner;
554 gdev->owner = THIS_MODULE;
556 gdev->descs = kcalloc(gc->ngpio, sizeof(gdev->descs[0]), GFP_KERNEL);
562 if (gc->ngpio == 0) {
563 chip_err(gc, "tried to insert a GPIO chip with zero lines\n");
568 if (gc->ngpio > FASTPATH_NGPIO)
569 chip_warn(gc, "line cnt %u is greater than fast path cnt %u\n",
570 gc->ngpio, FASTPATH_NGPIO);
572 gdev->label = kstrdup_const(gc->label ?: "unknown", GFP_KERNEL);
578 gdev->ngpio = gc->ngpio;
581 spin_lock_irqsave(&gpio_lock, flags);
584 * TODO: this allocates a Linux GPIO number base in the global
585 * GPIO numberspace for this chip. In the long run we want to
586 * get *rid* of this numberspace and use only descriptors, but
587 * it may be a pipe dream. It will not happen before we get rid
588 * of the sysfs interface anyways.
591 base = gpiochip_find_base(gc->ngpio);
594 spin_unlock_irqrestore(&gpio_lock, flags);
598 * TODO: it should not be necessary to reflect the assigned
599 * base outside of the GPIO subsystem. Go over drivers and
600 * see if anyone makes use of this, else drop this and assign
607 ret = gpiodev_add_to_list(gdev);
609 spin_unlock_irqrestore(&gpio_lock, flags);
613 for (i = 0; i < gc->ngpio; i++)
614 gdev->descs[i].gdev = gdev;
616 spin_unlock_irqrestore(&gpio_lock, flags);
618 BLOCKING_INIT_NOTIFIER_HEAD(&gdev->notifier);
620 #ifdef CONFIG_PINCTRL
621 INIT_LIST_HEAD(&gdev->pin_ranges);
624 ret = gpiochip_set_desc_names(gc);
626 goto err_remove_from_list;
628 ret = gpiochip_alloc_valid_mask(gc);
630 goto err_remove_from_list;
632 ret = of_gpiochip_add(gc);
634 goto err_free_gpiochip_mask;
636 ret = gpiochip_init_valid_mask(gc);
638 goto err_remove_of_chip;
640 for (i = 0; i < gc->ngpio; i++) {
641 struct gpio_desc *desc = &gdev->descs[i];
643 if (gc->get_direction && gpiochip_line_is_valid(gc, i)) {
644 assign_bit(FLAG_IS_OUT,
645 &desc->flags, !gc->get_direction(gc, i));
647 assign_bit(FLAG_IS_OUT,
648 &desc->flags, !gc->direction_input);
652 ret = gpiochip_add_pin_ranges(gc);
654 goto err_remove_of_chip;
656 acpi_gpiochip_add(gc);
658 machine_gpiochip_add(gc);
660 ret = gpiochip_irqchip_init_valid_mask(gc);
662 goto err_remove_acpi_chip;
664 ret = gpiochip_irqchip_init_hw(gc);
666 goto err_remove_acpi_chip;
668 ret = gpiochip_add_irqchip(gc, lock_key, request_key);
670 goto err_remove_irqchip_mask;
673 * By first adding the chardev, and then adding the device,
674 * we get a device node entry in sysfs under
675 * /sys/bus/gpio/devices/gpiochipN/dev that can be used for
676 * coldplug of device nodes and other udev business.
677 * We can do this only if gpiolib has been initialized.
678 * Otherwise, defer until later.
680 if (gpiolib_initialized) {
681 ret = gpiochip_setup_dev(gdev);
683 goto err_remove_irqchip;
688 gpiochip_irqchip_remove(gc);
689 err_remove_irqchip_mask:
690 gpiochip_irqchip_free_valid_mask(gc);
691 err_remove_acpi_chip:
692 acpi_gpiochip_remove(gc);
694 gpiochip_free_hogs(gc);
695 of_gpiochip_remove(gc);
696 err_free_gpiochip_mask:
697 gpiochip_remove_pin_ranges(gc);
698 gpiochip_free_valid_mask(gc);
699 err_remove_from_list:
700 spin_lock_irqsave(&gpio_lock, flags);
701 list_del(&gdev->list);
702 spin_unlock_irqrestore(&gpio_lock, flags);
704 kfree_const(gdev->label);
708 ida_simple_remove(&gpio_ida, gdev->id);
710 /* failures here can mean systems won't boot... */
711 pr_err("%s: GPIOs %d..%d (%s) failed to register, %d\n", __func__,
712 gdev->base, gdev->base + gdev->ngpio - 1,
713 gc->label ? : "generic", ret);
717 EXPORT_SYMBOL_GPL(gpiochip_add_data_with_key);
720 * gpiochip_get_data() - get per-subdriver data for the chip
724 * The per-subdriver data for the chip.
726 void *gpiochip_get_data(struct gpio_chip *gc)
728 return gc->gpiodev->data;
730 EXPORT_SYMBOL_GPL(gpiochip_get_data);
733 * gpiochip_remove() - unregister a gpio_chip
734 * @gc: the chip to unregister
736 * A gpio_chip with any GPIOs still requested may not be removed.
738 void gpiochip_remove(struct gpio_chip *gc)
740 struct gpio_device *gdev = gc->gpiodev;
744 /* FIXME: should the legacy sysfs handling be moved to gpio_device? */
745 gpiochip_sysfs_unregister(gdev);
746 gpiochip_free_hogs(gc);
747 /* Numb the device, cancelling all outstanding operations */
749 gpiochip_irqchip_remove(gc);
750 acpi_gpiochip_remove(gc);
751 of_gpiochip_remove(gc);
752 gpiochip_remove_pin_ranges(gc);
753 gpiochip_free_valid_mask(gc);
755 * We accept no more calls into the driver from this point, so
756 * NULL the driver data pointer
760 spin_lock_irqsave(&gpio_lock, flags);
761 for (i = 0; i < gdev->ngpio; i++) {
762 if (gpiochip_is_requested(gc, i))
765 spin_unlock_irqrestore(&gpio_lock, flags);
767 if (i != gdev->ngpio)
769 "REMOVING GPIOCHIP WITH GPIOS STILL REQUESTED\n");
772 * The gpiochip side puts its use of the device to rest here:
773 * if there are no userspace clients, the chardev and device will
774 * be removed, else it will be dangling until the last user is
777 gpiolib_cdev_unregister(gdev);
778 put_device(&gdev->dev);
780 EXPORT_SYMBOL_GPL(gpiochip_remove);
783 * gpiochip_find() - iterator for locating a specific gpio_chip
784 * @data: data to pass to match function
785 * @match: Callback function to check gpio_chip
787 * Similar to bus_find_device. It returns a reference to a gpio_chip as
788 * determined by a user supplied @match callback. The callback should return
789 * 0 if the device doesn't match and non-zero if it does. If the callback is
790 * non-zero, this function will return to the caller and not iterate over any
793 struct gpio_chip *gpiochip_find(void *data,
794 int (*match)(struct gpio_chip *gc,
797 struct gpio_device *gdev;
798 struct gpio_chip *gc = NULL;
801 spin_lock_irqsave(&gpio_lock, flags);
802 list_for_each_entry(gdev, &gpio_devices, list)
803 if (gdev->chip && match(gdev->chip, data)) {
808 spin_unlock_irqrestore(&gpio_lock, flags);
812 EXPORT_SYMBOL_GPL(gpiochip_find);
814 static int gpiochip_match_name(struct gpio_chip *gc, void *data)
816 const char *name = data;
818 return !strcmp(gc->label, name);
821 static struct gpio_chip *find_chip_by_name(const char *name)
823 return gpiochip_find((void *)name, gpiochip_match_name);
826 #ifdef CONFIG_GPIOLIB_IRQCHIP
829 * The following is irqchip helper code for gpiochips.
832 static int gpiochip_irqchip_init_hw(struct gpio_chip *gc)
834 struct gpio_irq_chip *girq = &gc->irq;
839 return girq->init_hw(gc);
842 static int gpiochip_irqchip_init_valid_mask(struct gpio_chip *gc)
844 struct gpio_irq_chip *girq = &gc->irq;
846 if (!girq->init_valid_mask)
849 girq->valid_mask = gpiochip_allocate_mask(gc);
850 if (!girq->valid_mask)
853 girq->init_valid_mask(gc, girq->valid_mask, gc->ngpio);
858 static void gpiochip_irqchip_free_valid_mask(struct gpio_chip *gc)
860 bitmap_free(gc->irq.valid_mask);
861 gc->irq.valid_mask = NULL;
864 bool gpiochip_irqchip_irq_valid(const struct gpio_chip *gc,
867 if (!gpiochip_line_is_valid(gc, offset))
869 /* No mask means all valid */
870 if (likely(!gc->irq.valid_mask))
872 return test_bit(offset, gc->irq.valid_mask);
874 EXPORT_SYMBOL_GPL(gpiochip_irqchip_irq_valid);
877 * gpiochip_set_cascaded_irqchip() - connects a cascaded irqchip to a gpiochip
878 * @gc: the gpiochip to set the irqchip chain to
879 * @parent_irq: the irq number corresponding to the parent IRQ for this
881 * @parent_handler: the parent interrupt handler for the accumulated IRQ
882 * coming out of the gpiochip. If the interrupt is nested rather than
883 * cascaded, pass NULL in this handler argument
885 static void gpiochip_set_cascaded_irqchip(struct gpio_chip *gc,
886 unsigned int parent_irq,
887 irq_flow_handler_t parent_handler)
889 struct gpio_irq_chip *girq = &gc->irq;
890 struct device *dev = &gc->gpiodev->dev;
893 chip_err(gc, "called %s before setting up irqchip\n",
898 if (parent_handler) {
901 "you cannot have chained interrupts on a chip that may sleep\n");
904 girq->parents = devm_kcalloc(dev, 1,
905 sizeof(*girq->parents),
907 if (!girq->parents) {
908 chip_err(gc, "out of memory allocating parent IRQ\n");
911 girq->parents[0] = parent_irq;
912 girq->num_parents = 1;
914 * The parent irqchip is already using the chip_data for this
915 * irqchip, so our callbacks simply use the handler_data.
917 irq_set_chained_handler_and_data(parent_irq, parent_handler,
923 * gpiochip_set_nested_irqchip() - connects a nested irqchip to a gpiochip
924 * @gc: the gpiochip to set the irqchip nested handler to
925 * @irqchip: the irqchip to nest to the gpiochip
926 * @parent_irq: the irq number corresponding to the parent IRQ for this
929 void gpiochip_set_nested_irqchip(struct gpio_chip *gc,
930 struct irq_chip *irqchip,
931 unsigned int parent_irq)
933 gpiochip_set_cascaded_irqchip(gc, parent_irq, NULL);
935 EXPORT_SYMBOL_GPL(gpiochip_set_nested_irqchip);
937 #ifdef CONFIG_IRQ_DOMAIN_HIERARCHY
940 * gpiochip_set_hierarchical_irqchip() - connects a hierarchical irqchip
942 * @gc: the gpiochip to set the irqchip hierarchical handler to
943 * @irqchip: the irqchip to handle this level of the hierarchy, the interrupt
944 * will then percolate up to the parent
946 static void gpiochip_set_hierarchical_irqchip(struct gpio_chip *gc,
947 struct irq_chip *irqchip)
949 /* DT will deal with mapping each IRQ as we go along */
950 if (is_of_node(gc->irq.fwnode))
954 * This is for legacy and boardfile "irqchip" fwnodes: allocate
955 * irqs upfront instead of dynamically since we don't have the
956 * dynamic type of allocation that hardware description languages
957 * provide. Once all GPIO drivers using board files are gone from
958 * the kernel we can delete this code, but for a transitional period
959 * it is necessary to keep this around.
961 if (is_fwnode_irqchip(gc->irq.fwnode)) {
965 for (i = 0; i < gc->ngpio; i++) {
966 struct irq_fwspec fwspec;
967 unsigned int parent_hwirq;
968 unsigned int parent_type;
969 struct gpio_irq_chip *girq = &gc->irq;
972 * We call the child to parent translation function
973 * only to check if the child IRQ is valid or not.
974 * Just pick the rising edge type here as that is what
975 * we likely need to support.
977 ret = girq->child_to_parent_hwirq(gc, i,
978 IRQ_TYPE_EDGE_RISING,
982 chip_err(gc, "skip set-up on hwirq %d\n",
987 fwspec.fwnode = gc->irq.fwnode;
988 /* This is the hwirq for the GPIO line side of things */
989 fwspec.param[0] = girq->child_offset_to_irq(gc, i);
990 /* Just pick something */
991 fwspec.param[1] = IRQ_TYPE_EDGE_RISING;
992 fwspec.param_count = 2;
993 ret = __irq_domain_alloc_irqs(gc->irq.domain,
994 /* just pick something */
1003 "can not allocate irq for GPIO line %d parent hwirq %d in hierarchy domain: %d\n",
1010 chip_err(gc, "%s unknown fwnode type proceed anyway\n", __func__);
1015 static int gpiochip_hierarchy_irq_domain_translate(struct irq_domain *d,
1016 struct irq_fwspec *fwspec,
1017 unsigned long *hwirq,
1020 /* We support standard DT translation */
1021 if (is_of_node(fwspec->fwnode) && fwspec->param_count == 2) {
1022 return irq_domain_translate_twocell(d, fwspec, hwirq, type);
1025 /* This is for board files and others not using DT */
1026 if (is_fwnode_irqchip(fwspec->fwnode)) {
1029 ret = irq_domain_translate_twocell(d, fwspec, hwirq, type);
1032 WARN_ON(*type == IRQ_TYPE_NONE);
1038 static int gpiochip_hierarchy_irq_domain_alloc(struct irq_domain *d,
1040 unsigned int nr_irqs,
1043 struct gpio_chip *gc = d->host_data;
1044 irq_hw_number_t hwirq;
1045 unsigned int type = IRQ_TYPE_NONE;
1046 struct irq_fwspec *fwspec = data;
1048 unsigned int parent_hwirq;
1049 unsigned int parent_type;
1050 struct gpio_irq_chip *girq = &gc->irq;
1054 * The nr_irqs parameter is always one except for PCI multi-MSI
1055 * so this should not happen.
1057 WARN_ON(nr_irqs != 1);
1059 ret = gc->irq.child_irq_domain_ops.translate(d, fwspec, &hwirq, &type);
1063 chip_dbg(gc, "allocate IRQ %d, hwirq %lu\n", irq, hwirq);
1065 ret = girq->child_to_parent_hwirq(gc, hwirq, type,
1066 &parent_hwirq, &parent_type);
1068 chip_err(gc, "can't look up hwirq %lu\n", hwirq);
1071 chip_dbg(gc, "found parent hwirq %u\n", parent_hwirq);
1074 * We set handle_bad_irq because the .set_type() should
1075 * always be invoked and set the right type of handler.
1077 irq_domain_set_info(d,
1086 /* This parent only handles asserted level IRQs */
1087 parent_arg = girq->populate_parent_alloc_arg(gc, parent_hwirq, parent_type);
1091 chip_dbg(gc, "alloc_irqs_parent for %d parent hwirq %d\n",
1093 irq_set_lockdep_class(irq, gc->irq.lock_key, gc->irq.request_key);
1094 ret = irq_domain_alloc_irqs_parent(d, irq, 1, parent_arg);
1096 * If the parent irqdomain is msi, the interrupts have already
1097 * been allocated, so the EEXIST is good.
1099 if (irq_domain_is_msi(d->parent) && (ret == -EEXIST))
1103 "failed to allocate parent hwirq %d for hwirq %lu\n",
1104 parent_hwirq, hwirq);
1110 static unsigned int gpiochip_child_offset_to_irq_noop(struct gpio_chip *gc,
1111 unsigned int offset)
1116 static void gpiochip_hierarchy_setup_domain_ops(struct irq_domain_ops *ops)
1118 ops->activate = gpiochip_irq_domain_activate;
1119 ops->deactivate = gpiochip_irq_domain_deactivate;
1120 ops->alloc = gpiochip_hierarchy_irq_domain_alloc;
1121 ops->free = irq_domain_free_irqs_common;
1124 * We only allow overriding the translate() function for
1125 * hierarchical chips, and this should only be done if the user
1126 * really need something other than 1:1 translation.
1128 if (!ops->translate)
1129 ops->translate = gpiochip_hierarchy_irq_domain_translate;
1132 static int gpiochip_hierarchy_add_domain(struct gpio_chip *gc)
1134 if (!gc->irq.child_to_parent_hwirq ||
1136 chip_err(gc, "missing irqdomain vital data\n");
1140 if (!gc->irq.child_offset_to_irq)
1141 gc->irq.child_offset_to_irq = gpiochip_child_offset_to_irq_noop;
1143 if (!gc->irq.populate_parent_alloc_arg)
1144 gc->irq.populate_parent_alloc_arg =
1145 gpiochip_populate_parent_fwspec_twocell;
1147 gpiochip_hierarchy_setup_domain_ops(&gc->irq.child_irq_domain_ops);
1149 gc->irq.domain = irq_domain_create_hierarchy(
1150 gc->irq.parent_domain,
1154 &gc->irq.child_irq_domain_ops,
1157 if (!gc->irq.domain)
1160 gpiochip_set_hierarchical_irqchip(gc, gc->irq.chip);
1165 static bool gpiochip_hierarchy_is_hierarchical(struct gpio_chip *gc)
1167 return !!gc->irq.parent_domain;
1170 void *gpiochip_populate_parent_fwspec_twocell(struct gpio_chip *gc,
1171 unsigned int parent_hwirq,
1172 unsigned int parent_type)
1174 struct irq_fwspec *fwspec;
1176 fwspec = kmalloc(sizeof(*fwspec), GFP_KERNEL);
1180 fwspec->fwnode = gc->irq.parent_domain->fwnode;
1181 fwspec->param_count = 2;
1182 fwspec->param[0] = parent_hwirq;
1183 fwspec->param[1] = parent_type;
1187 EXPORT_SYMBOL_GPL(gpiochip_populate_parent_fwspec_twocell);
1189 void *gpiochip_populate_parent_fwspec_fourcell(struct gpio_chip *gc,
1190 unsigned int parent_hwirq,
1191 unsigned int parent_type)
1193 struct irq_fwspec *fwspec;
1195 fwspec = kmalloc(sizeof(*fwspec), GFP_KERNEL);
1199 fwspec->fwnode = gc->irq.parent_domain->fwnode;
1200 fwspec->param_count = 4;
1201 fwspec->param[0] = 0;
1202 fwspec->param[1] = parent_hwirq;
1203 fwspec->param[2] = 0;
1204 fwspec->param[3] = parent_type;
1208 EXPORT_SYMBOL_GPL(gpiochip_populate_parent_fwspec_fourcell);
1212 static int gpiochip_hierarchy_add_domain(struct gpio_chip *gc)
1217 static bool gpiochip_hierarchy_is_hierarchical(struct gpio_chip *gc)
1222 #endif /* CONFIG_IRQ_DOMAIN_HIERARCHY */
1225 * gpiochip_irq_map() - maps an IRQ into a GPIO irqchip
1226 * @d: the irqdomain used by this irqchip
1227 * @irq: the global irq number used by this GPIO irqchip irq
1228 * @hwirq: the local IRQ/GPIO line offset on this gpiochip
1230 * This function will set up the mapping for a certain IRQ line on a
1231 * gpiochip by assigning the gpiochip as chip data, and using the irqchip
1232 * stored inside the gpiochip.
1234 int gpiochip_irq_map(struct irq_domain *d, unsigned int irq,
1235 irq_hw_number_t hwirq)
1237 struct gpio_chip *gc = d->host_data;
1240 if (!gpiochip_irqchip_irq_valid(gc, hwirq))
1243 irq_set_chip_data(irq, gc);
1245 * This lock class tells lockdep that GPIO irqs are in a different
1246 * category than their parents, so it won't report false recursion.
1248 irq_set_lockdep_class(irq, gc->irq.lock_key, gc->irq.request_key);
1249 irq_set_chip_and_handler(irq, gc->irq.chip, gc->irq.handler);
1250 /* Chips that use nested thread handlers have them marked */
1251 if (gc->irq.threaded)
1252 irq_set_nested_thread(irq, 1);
1253 irq_set_noprobe(irq);
1255 if (gc->irq.num_parents == 1)
1256 ret = irq_set_parent(irq, gc->irq.parents[0]);
1257 else if (gc->irq.map)
1258 ret = irq_set_parent(irq, gc->irq.map[hwirq]);
1264 * No set-up of the hardware will happen if IRQ_TYPE_NONE
1265 * is passed as default type.
1267 if (gc->irq.default_type != IRQ_TYPE_NONE)
1268 irq_set_irq_type(irq, gc->irq.default_type);
1272 EXPORT_SYMBOL_GPL(gpiochip_irq_map);
1274 void gpiochip_irq_unmap(struct irq_domain *d, unsigned int irq)
1276 struct gpio_chip *gc = d->host_data;
1278 if (gc->irq.threaded)
1279 irq_set_nested_thread(irq, 0);
1280 irq_set_chip_and_handler(irq, NULL, NULL);
1281 irq_set_chip_data(irq, NULL);
1283 EXPORT_SYMBOL_GPL(gpiochip_irq_unmap);
1285 static const struct irq_domain_ops gpiochip_domain_ops = {
1286 .map = gpiochip_irq_map,
1287 .unmap = gpiochip_irq_unmap,
1288 /* Virtually all GPIO irqchips are twocell:ed */
1289 .xlate = irq_domain_xlate_twocell,
1293 * TODO: move these activate/deactivate in under the hierarchicial
1294 * irqchip implementation as static once SPMI and SSBI (all external
1295 * users) are phased over.
1298 * gpiochip_irq_domain_activate() - Lock a GPIO to be used as an IRQ
1299 * @domain: The IRQ domain used by this IRQ chip
1300 * @data: Outermost irq_data associated with the IRQ
1301 * @reserve: If set, only reserve an interrupt vector instead of assigning one
1303 * This function is a wrapper that calls gpiochip_lock_as_irq() and is to be
1304 * used as the activate function for the &struct irq_domain_ops. The host_data
1305 * for the IRQ domain must be the &struct gpio_chip.
1307 int gpiochip_irq_domain_activate(struct irq_domain *domain,
1308 struct irq_data *data, bool reserve)
1310 struct gpio_chip *gc = domain->host_data;
1312 return gpiochip_lock_as_irq(gc, data->hwirq);
1314 EXPORT_SYMBOL_GPL(gpiochip_irq_domain_activate);
1317 * gpiochip_irq_domain_deactivate() - Unlock a GPIO used as an IRQ
1318 * @domain: The IRQ domain used by this IRQ chip
1319 * @data: Outermost irq_data associated with the IRQ
1321 * This function is a wrapper that will call gpiochip_unlock_as_irq() and is to
1322 * be used as the deactivate function for the &struct irq_domain_ops. The
1323 * host_data for the IRQ domain must be the &struct gpio_chip.
1325 void gpiochip_irq_domain_deactivate(struct irq_domain *domain,
1326 struct irq_data *data)
1328 struct gpio_chip *gc = domain->host_data;
1330 return gpiochip_unlock_as_irq(gc, data->hwirq);
1332 EXPORT_SYMBOL_GPL(gpiochip_irq_domain_deactivate);
1334 static int gpiochip_to_irq(struct gpio_chip *gc, unsigned offset)
1336 struct irq_domain *domain = gc->irq.domain;
1338 if (!gpiochip_irqchip_irq_valid(gc, offset))
1341 #ifdef CONFIG_IRQ_DOMAIN_HIERARCHY
1342 if (irq_domain_is_hierarchy(domain)) {
1343 struct irq_fwspec spec;
1345 spec.fwnode = domain->fwnode;
1346 spec.param_count = 2;
1347 spec.param[0] = gc->irq.child_offset_to_irq(gc, offset);
1348 spec.param[1] = IRQ_TYPE_NONE;
1350 return irq_create_fwspec_mapping(&spec);
1354 return irq_create_mapping(domain, offset);
1357 static int gpiochip_irq_reqres(struct irq_data *d)
1359 struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
1361 return gpiochip_reqres_irq(gc, d->hwirq);
1364 static void gpiochip_irq_relres(struct irq_data *d)
1366 struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
1368 gpiochip_relres_irq(gc, d->hwirq);
1371 static void gpiochip_irq_mask(struct irq_data *d)
1373 struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
1375 if (gc->irq.irq_mask)
1376 gc->irq.irq_mask(d);
1377 gpiochip_disable_irq(gc, d->hwirq);
1380 static void gpiochip_irq_unmask(struct irq_data *d)
1382 struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
1384 gpiochip_enable_irq(gc, d->hwirq);
1385 if (gc->irq.irq_unmask)
1386 gc->irq.irq_unmask(d);
1389 static void gpiochip_irq_enable(struct irq_data *d)
1391 struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
1393 gpiochip_enable_irq(gc, d->hwirq);
1394 gc->irq.irq_enable(d);
1397 static void gpiochip_irq_disable(struct irq_data *d)
1399 struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
1401 gc->irq.irq_disable(d);
1402 gpiochip_disable_irq(gc, d->hwirq);
1405 static void gpiochip_set_irq_hooks(struct gpio_chip *gc)
1407 struct irq_chip *irqchip = gc->irq.chip;
1409 if (!irqchip->irq_request_resources &&
1410 !irqchip->irq_release_resources) {
1411 irqchip->irq_request_resources = gpiochip_irq_reqres;
1412 irqchip->irq_release_resources = gpiochip_irq_relres;
1414 if (WARN_ON(gc->irq.irq_enable))
1416 /* Check if the irqchip already has this hook... */
1417 if (irqchip->irq_enable == gpiochip_irq_enable) {
1419 * ...and if so, give a gentle warning that this is bad
1423 "detected irqchip that is shared with multiple gpiochips: please fix the driver.\n");
1427 if (irqchip->irq_disable) {
1428 gc->irq.irq_disable = irqchip->irq_disable;
1429 irqchip->irq_disable = gpiochip_irq_disable;
1431 gc->irq.irq_mask = irqchip->irq_mask;
1432 irqchip->irq_mask = gpiochip_irq_mask;
1435 if (irqchip->irq_enable) {
1436 gc->irq.irq_enable = irqchip->irq_enable;
1437 irqchip->irq_enable = gpiochip_irq_enable;
1439 gc->irq.irq_unmask = irqchip->irq_unmask;
1440 irqchip->irq_unmask = gpiochip_irq_unmask;
1445 * gpiochip_add_irqchip() - adds an IRQ chip to a GPIO chip
1446 * @gc: the GPIO chip to add the IRQ chip to
1447 * @lock_key: lockdep class for IRQ lock
1448 * @request_key: lockdep class for IRQ request
1450 static int gpiochip_add_irqchip(struct gpio_chip *gc,
1451 struct lock_class_key *lock_key,
1452 struct lock_class_key *request_key)
1454 struct irq_chip *irqchip = gc->irq.chip;
1455 const struct irq_domain_ops *ops = NULL;
1456 struct device_node *np;
1463 if (gc->irq.parent_handler && gc->can_sleep) {
1464 chip_err(gc, "you cannot have chained interrupts on a chip that may sleep\n");
1468 np = gc->gpiodev->dev.of_node;
1469 type = gc->irq.default_type;
1472 * Specifying a default trigger is a terrible idea if DT or ACPI is
1473 * used to configure the interrupts, as you may end up with
1474 * conflicting triggers. Tell the user, and reset to NONE.
1476 if (WARN(np && type != IRQ_TYPE_NONE,
1477 "%s: Ignoring %u default trigger\n", np->full_name, type))
1478 type = IRQ_TYPE_NONE;
1480 if (has_acpi_companion(gc->parent) && type != IRQ_TYPE_NONE) {
1481 acpi_handle_warn(ACPI_HANDLE(gc->parent),
1482 "Ignoring %u default trigger\n", type);
1483 type = IRQ_TYPE_NONE;
1486 gc->to_irq = gpiochip_to_irq;
1487 gc->irq.default_type = type;
1488 gc->irq.lock_key = lock_key;
1489 gc->irq.request_key = request_key;
1491 /* If a parent irqdomain is provided, let's build a hierarchy */
1492 if (gpiochip_hierarchy_is_hierarchical(gc)) {
1493 int ret = gpiochip_hierarchy_add_domain(gc);
1497 /* Some drivers provide custom irqdomain ops */
1498 if (gc->irq.domain_ops)
1499 ops = gc->irq.domain_ops;
1502 ops = &gpiochip_domain_ops;
1503 gc->irq.domain = irq_domain_add_simple(np,
1507 if (!gc->irq.domain)
1511 if (gc->irq.parent_handler) {
1512 void *data = gc->irq.parent_handler_data ?: gc;
1514 for (i = 0; i < gc->irq.num_parents; i++) {
1516 * The parent IRQ chip is already using the chip_data
1517 * for this IRQ chip, so our callbacks simply use the
1520 irq_set_chained_handler_and_data(gc->irq.parents[i],
1521 gc->irq.parent_handler,
1526 gpiochip_set_irq_hooks(gc);
1528 acpi_gpiochip_request_interrupts(gc);
1534 * gpiochip_irqchip_remove() - removes an irqchip added to a gpiochip
1535 * @gc: the gpiochip to remove the irqchip from
1537 * This is called only from gpiochip_remove()
1539 static void gpiochip_irqchip_remove(struct gpio_chip *gc)
1541 struct irq_chip *irqchip = gc->irq.chip;
1542 unsigned int offset;
1544 acpi_gpiochip_free_interrupts(gc);
1546 if (irqchip && gc->irq.parent_handler) {
1547 struct gpio_irq_chip *irq = &gc->irq;
1550 for (i = 0; i < irq->num_parents; i++)
1551 irq_set_chained_handler_and_data(irq->parents[i],
1555 /* Remove all IRQ mappings and delete the domain */
1556 if (gc->irq.domain) {
1559 for (offset = 0; offset < gc->ngpio; offset++) {
1560 if (!gpiochip_irqchip_irq_valid(gc, offset))
1563 irq = irq_find_mapping(gc->irq.domain, offset);
1564 irq_dispose_mapping(irq);
1567 irq_domain_remove(gc->irq.domain);
1571 if (irqchip->irq_request_resources == gpiochip_irq_reqres) {
1572 irqchip->irq_request_resources = NULL;
1573 irqchip->irq_release_resources = NULL;
1575 if (irqchip->irq_enable == gpiochip_irq_enable) {
1576 irqchip->irq_enable = gc->irq.irq_enable;
1577 irqchip->irq_disable = gc->irq.irq_disable;
1580 gc->irq.irq_enable = NULL;
1581 gc->irq.irq_disable = NULL;
1582 gc->irq.chip = NULL;
1584 gpiochip_irqchip_free_valid_mask(gc);
1588 * gpiochip_irqchip_add_key() - adds an irqchip to a gpiochip
1589 * @gc: the gpiochip to add the irqchip to
1590 * @irqchip: the irqchip to add to the gpiochip
1591 * @first_irq: if not dynamically assigned, the base (first) IRQ to
1592 * allocate gpiochip irqs from
1593 * @handler: the irq handler to use (often a predefined irq core function)
1594 * @type: the default type for IRQs on this irqchip, pass IRQ_TYPE_NONE
1595 * to have the core avoid setting up any default type in the hardware.
1596 * @threaded: whether this irqchip uses a nested thread handler
1597 * @lock_key: lockdep class for IRQ lock
1598 * @request_key: lockdep class for IRQ request
1600 * This function closely associates a certain irqchip with a certain
1601 * gpiochip, providing an irq domain to translate the local IRQs to
1602 * global irqs in the gpiolib core, and making sure that the gpiochip
1603 * is passed as chip data to all related functions. Driver callbacks
1604 * need to use gpiochip_get_data() to get their local state containers back
1605 * from the gpiochip passed as chip data. An irqdomain will be stored
1606 * in the gpiochip that shall be used by the driver to handle IRQ number
1607 * translation. The gpiochip will need to be initialized and registered
1608 * before calling this function.
1610 * This function will handle two cell:ed simple IRQs and assumes all
1611 * the pins on the gpiochip can generate a unique IRQ. Everything else
1612 * need to be open coded.
1614 int gpiochip_irqchip_add_key(struct gpio_chip *gc,
1615 struct irq_chip *irqchip,
1616 unsigned int first_irq,
1617 irq_flow_handler_t handler,
1620 struct lock_class_key *lock_key,
1621 struct lock_class_key *request_key)
1623 struct device_node *of_node;
1625 if (!gc || !irqchip)
1629 chip_err(gc, "missing gpiochip .dev parent pointer\n");
1632 gc->irq.threaded = threaded;
1633 of_node = gc->parent->of_node;
1634 #ifdef CONFIG_OF_GPIO
1636 * If the gpiochip has an assigned OF node this takes precedence
1637 * FIXME: get rid of this and use gc->parent->of_node
1641 of_node = gc->of_node;
1644 * Specifying a default trigger is a terrible idea if DT or ACPI is
1645 * used to configure the interrupts, as you may end-up with
1646 * conflicting triggers. Tell the user, and reset to NONE.
1648 if (WARN(of_node && type != IRQ_TYPE_NONE,
1649 "%pOF: Ignoring %d default trigger\n", of_node, type))
1650 type = IRQ_TYPE_NONE;
1651 if (has_acpi_companion(gc->parent) && type != IRQ_TYPE_NONE) {
1652 acpi_handle_warn(ACPI_HANDLE(gc->parent),
1653 "Ignoring %d default trigger\n", type);
1654 type = IRQ_TYPE_NONE;
1657 gc->irq.chip = irqchip;
1658 gc->irq.handler = handler;
1659 gc->irq.default_type = type;
1660 gc->to_irq = gpiochip_to_irq;
1661 gc->irq.lock_key = lock_key;
1662 gc->irq.request_key = request_key;
1663 gc->irq.domain = irq_domain_add_simple(of_node,
1664 gc->ngpio, first_irq,
1665 &gpiochip_domain_ops, gc);
1666 if (!gc->irq.domain) {
1667 gc->irq.chip = NULL;
1671 gpiochip_set_irq_hooks(gc);
1673 acpi_gpiochip_request_interrupts(gc);
1677 EXPORT_SYMBOL_GPL(gpiochip_irqchip_add_key);
1680 * gpiochip_irqchip_add_domain() - adds an irqdomain to a gpiochip
1681 * @gc: the gpiochip to add the irqchip to
1682 * @domain: the irqdomain to add to the gpiochip
1684 * This function adds an IRQ domain to the gpiochip.
1686 int gpiochip_irqchip_add_domain(struct gpio_chip *gc,
1687 struct irq_domain *domain)
1692 gc->to_irq = gpiochip_to_irq;
1693 gc->irq.domain = domain;
1697 EXPORT_SYMBOL_GPL(gpiochip_irqchip_add_domain);
1699 #else /* CONFIG_GPIOLIB_IRQCHIP */
1701 static inline int gpiochip_add_irqchip(struct gpio_chip *gc,
1702 struct lock_class_key *lock_key,
1703 struct lock_class_key *request_key)
1707 static void gpiochip_irqchip_remove(struct gpio_chip *gc) {}
1709 static inline int gpiochip_irqchip_init_hw(struct gpio_chip *gc)
1714 static inline int gpiochip_irqchip_init_valid_mask(struct gpio_chip *gc)
1718 static inline void gpiochip_irqchip_free_valid_mask(struct gpio_chip *gc)
1721 #endif /* CONFIG_GPIOLIB_IRQCHIP */
1724 * gpiochip_generic_request() - request the gpio function for a pin
1725 * @gc: the gpiochip owning the GPIO
1726 * @offset: the offset of the GPIO to request for GPIO function
1728 int gpiochip_generic_request(struct gpio_chip *gc, unsigned offset)
1730 #ifdef CONFIG_PINCTRL
1731 if (list_empty(&gc->gpiodev->pin_ranges))
1735 return pinctrl_gpio_request(gc->gpiodev->base + offset);
1737 EXPORT_SYMBOL_GPL(gpiochip_generic_request);
1740 * gpiochip_generic_free() - free the gpio function from a pin
1741 * @gc: the gpiochip to request the gpio function for
1742 * @offset: the offset of the GPIO to free from GPIO function
1744 void gpiochip_generic_free(struct gpio_chip *gc, unsigned offset)
1746 pinctrl_gpio_free(gc->gpiodev->base + offset);
1748 EXPORT_SYMBOL_GPL(gpiochip_generic_free);
1751 * gpiochip_generic_config() - apply configuration for a pin
1752 * @gc: the gpiochip owning the GPIO
1753 * @offset: the offset of the GPIO to apply the configuration
1754 * @config: the configuration to be applied
1756 int gpiochip_generic_config(struct gpio_chip *gc, unsigned offset,
1757 unsigned long config)
1759 return pinctrl_gpio_set_config(gc->gpiodev->base + offset, config);
1761 EXPORT_SYMBOL_GPL(gpiochip_generic_config);
1763 #ifdef CONFIG_PINCTRL
1766 * gpiochip_add_pingroup_range() - add a range for GPIO <-> pin mapping
1767 * @gc: the gpiochip to add the range for
1768 * @pctldev: the pin controller to map to
1769 * @gpio_offset: the start offset in the current gpio_chip number space
1770 * @pin_group: name of the pin group inside the pin controller
1772 * Calling this function directly from a DeviceTree-supported
1773 * pinctrl driver is DEPRECATED. Please see Section 2.1 of
1774 * Documentation/devicetree/bindings/gpio/gpio.txt on how to
1775 * bind pinctrl and gpio drivers via the "gpio-ranges" property.
1777 int gpiochip_add_pingroup_range(struct gpio_chip *gc,
1778 struct pinctrl_dev *pctldev,
1779 unsigned int gpio_offset, const char *pin_group)
1781 struct gpio_pin_range *pin_range;
1782 struct gpio_device *gdev = gc->gpiodev;
1785 pin_range = kzalloc(sizeof(*pin_range), GFP_KERNEL);
1787 chip_err(gc, "failed to allocate pin ranges\n");
1791 /* Use local offset as range ID */
1792 pin_range->range.id = gpio_offset;
1793 pin_range->range.gc = gc;
1794 pin_range->range.name = gc->label;
1795 pin_range->range.base = gdev->base + gpio_offset;
1796 pin_range->pctldev = pctldev;
1798 ret = pinctrl_get_group_pins(pctldev, pin_group,
1799 &pin_range->range.pins,
1800 &pin_range->range.npins);
1806 pinctrl_add_gpio_range(pctldev, &pin_range->range);
1808 chip_dbg(gc, "created GPIO range %d->%d ==> %s PINGRP %s\n",
1809 gpio_offset, gpio_offset + pin_range->range.npins - 1,
1810 pinctrl_dev_get_devname(pctldev), pin_group);
1812 list_add_tail(&pin_range->node, &gdev->pin_ranges);
1816 EXPORT_SYMBOL_GPL(gpiochip_add_pingroup_range);
1819 * gpiochip_add_pin_range() - add a range for GPIO <-> pin mapping
1820 * @gc: the gpiochip to add the range for
1821 * @pinctl_name: the dev_name() of the pin controller to map to
1822 * @gpio_offset: the start offset in the current gpio_chip number space
1823 * @pin_offset: the start offset in the pin controller number space
1824 * @npins: the number of pins from the offset of each pin space (GPIO and
1825 * pin controller) to accumulate in this range
1828 * 0 on success, or a negative error-code on failure.
1830 * Calling this function directly from a DeviceTree-supported
1831 * pinctrl driver is DEPRECATED. Please see Section 2.1 of
1832 * Documentation/devicetree/bindings/gpio/gpio.txt on how to
1833 * bind pinctrl and gpio drivers via the "gpio-ranges" property.
1835 int gpiochip_add_pin_range(struct gpio_chip *gc, const char *pinctl_name,
1836 unsigned int gpio_offset, unsigned int pin_offset,
1839 struct gpio_pin_range *pin_range;
1840 struct gpio_device *gdev = gc->gpiodev;
1843 pin_range = kzalloc(sizeof(*pin_range), GFP_KERNEL);
1845 chip_err(gc, "failed to allocate pin ranges\n");
1849 /* Use local offset as range ID */
1850 pin_range->range.id = gpio_offset;
1851 pin_range->range.gc = gc;
1852 pin_range->range.name = gc->label;
1853 pin_range->range.base = gdev->base + gpio_offset;
1854 pin_range->range.pin_base = pin_offset;
1855 pin_range->range.npins = npins;
1856 pin_range->pctldev = pinctrl_find_and_add_gpio_range(pinctl_name,
1858 if (IS_ERR(pin_range->pctldev)) {
1859 ret = PTR_ERR(pin_range->pctldev);
1860 chip_err(gc, "could not create pin range\n");
1864 chip_dbg(gc, "created GPIO range %d->%d ==> %s PIN %d->%d\n",
1865 gpio_offset, gpio_offset + npins - 1,
1867 pin_offset, pin_offset + npins - 1);
1869 list_add_tail(&pin_range->node, &gdev->pin_ranges);
1873 EXPORT_SYMBOL_GPL(gpiochip_add_pin_range);
1876 * gpiochip_remove_pin_ranges() - remove all the GPIO <-> pin mappings
1877 * @gc: the chip to remove all the mappings for
1879 void gpiochip_remove_pin_ranges(struct gpio_chip *gc)
1881 struct gpio_pin_range *pin_range, *tmp;
1882 struct gpio_device *gdev = gc->gpiodev;
1884 list_for_each_entry_safe(pin_range, tmp, &gdev->pin_ranges, node) {
1885 list_del(&pin_range->node);
1886 pinctrl_remove_gpio_range(pin_range->pctldev,
1891 EXPORT_SYMBOL_GPL(gpiochip_remove_pin_ranges);
1893 #endif /* CONFIG_PINCTRL */
1895 /* These "optional" allocation calls help prevent drivers from stomping
1896 * on each other, and help provide better diagnostics in debugfs.
1897 * They're called even less than the "set direction" calls.
1899 static int gpiod_request_commit(struct gpio_desc *desc, const char *label)
1901 struct gpio_chip *gc = desc->gdev->chip;
1903 unsigned long flags;
1907 label = kstrdup_const(label, GFP_KERNEL);
1912 spin_lock_irqsave(&gpio_lock, flags);
1914 /* NOTE: gpio_request() can be called in early boot,
1915 * before IRQs are enabled, for non-sleeping (SOC) GPIOs.
1918 if (test_and_set_bit(FLAG_REQUESTED, &desc->flags) == 0) {
1919 desc_set_label(desc, label ? : "?");
1928 /* gc->request may sleep */
1929 spin_unlock_irqrestore(&gpio_lock, flags);
1930 offset = gpio_chip_hwgpio(desc);
1931 if (gpiochip_line_is_valid(gc, offset))
1932 ret = gc->request(gc, offset);
1935 spin_lock_irqsave(&gpio_lock, flags);
1938 desc_set_label(desc, NULL);
1940 clear_bit(FLAG_REQUESTED, &desc->flags);
1944 if (gc->get_direction) {
1945 /* gc->get_direction may sleep */
1946 spin_unlock_irqrestore(&gpio_lock, flags);
1947 gpiod_get_direction(desc);
1948 spin_lock_irqsave(&gpio_lock, flags);
1951 spin_unlock_irqrestore(&gpio_lock, flags);
1956 * This descriptor validation needs to be inserted verbatim into each
1957 * function taking a descriptor, so we need to use a preprocessor
1958 * macro to avoid endless duplication. If the desc is NULL it is an
1959 * optional GPIO and calls should just bail out.
1961 static int validate_desc(const struct gpio_desc *desc, const char *func)
1966 pr_warn("%s: invalid GPIO (errorpointer)\n", func);
1967 return PTR_ERR(desc);
1970 pr_warn("%s: invalid GPIO (no device)\n", func);
1973 if (!desc->gdev->chip) {
1974 dev_warn(&desc->gdev->dev,
1975 "%s: backing chip is gone\n", func);
1981 #define VALIDATE_DESC(desc) do { \
1982 int __valid = validate_desc(desc, __func__); \
1987 #define VALIDATE_DESC_VOID(desc) do { \
1988 int __valid = validate_desc(desc, __func__); \
1993 int gpiod_request(struct gpio_desc *desc, const char *label)
1995 int ret = -EPROBE_DEFER;
1996 struct gpio_device *gdev;
1998 VALIDATE_DESC(desc);
2001 if (try_module_get(gdev->owner)) {
2002 ret = gpiod_request_commit(desc, label);
2004 module_put(gdev->owner);
2006 get_device(&gdev->dev);
2010 gpiod_dbg(desc, "%s: status %d\n", __func__, ret);
2015 static bool gpiod_free_commit(struct gpio_desc *desc)
2018 unsigned long flags;
2019 struct gpio_chip *gc;
2023 gpiod_unexport(desc);
2025 spin_lock_irqsave(&gpio_lock, flags);
2027 gc = desc->gdev->chip;
2028 if (gc && test_bit(FLAG_REQUESTED, &desc->flags)) {
2030 spin_unlock_irqrestore(&gpio_lock, flags);
2031 might_sleep_if(gc->can_sleep);
2032 gc->free(gc, gpio_chip_hwgpio(desc));
2033 spin_lock_irqsave(&gpio_lock, flags);
2035 kfree_const(desc->label);
2036 desc_set_label(desc, NULL);
2037 clear_bit(FLAG_ACTIVE_LOW, &desc->flags);
2038 clear_bit(FLAG_REQUESTED, &desc->flags);
2039 clear_bit(FLAG_OPEN_DRAIN, &desc->flags);
2040 clear_bit(FLAG_OPEN_SOURCE, &desc->flags);
2041 clear_bit(FLAG_PULL_UP, &desc->flags);
2042 clear_bit(FLAG_PULL_DOWN, &desc->flags);
2043 clear_bit(FLAG_BIAS_DISABLE, &desc->flags);
2044 clear_bit(FLAG_IS_HOGGED, &desc->flags);
2045 #ifdef CONFIG_OF_DYNAMIC
2051 spin_unlock_irqrestore(&gpio_lock, flags);
2052 blocking_notifier_call_chain(&desc->gdev->notifier,
2053 GPIOLINE_CHANGED_RELEASED, desc);
2058 void gpiod_free(struct gpio_desc *desc)
2060 if (desc && desc->gdev && gpiod_free_commit(desc)) {
2061 module_put(desc->gdev->owner);
2062 put_device(&desc->gdev->dev);
2064 WARN_ON(extra_checks);
2069 * gpiochip_is_requested - return string iff signal was requested
2070 * @gc: controller managing the signal
2071 * @offset: of signal within controller's 0..(ngpio - 1) range
2073 * Returns NULL if the GPIO is not currently requested, else a string.
2074 * The string returned is the label passed to gpio_request(); if none has been
2075 * passed it is a meaningless, non-NULL constant.
2077 * This function is for use by GPIO controller drivers. The label can
2078 * help with diagnostics, and knowing that the signal is used as a GPIO
2079 * can help avoid accidentally multiplexing it to another controller.
2081 const char *gpiochip_is_requested(struct gpio_chip *gc, unsigned offset)
2083 struct gpio_desc *desc;
2085 if (offset >= gc->ngpio)
2088 desc = gpiochip_get_desc(gc, offset);
2092 if (test_bit(FLAG_REQUESTED, &desc->flags) == 0)
2096 EXPORT_SYMBOL_GPL(gpiochip_is_requested);
2099 * gpiochip_request_own_desc - Allow GPIO chip to request its own descriptor
2101 * @hwnum: hardware number of the GPIO for which to request the descriptor
2102 * @label: label for the GPIO
2103 * @lflags: lookup flags for this GPIO or 0 if default, this can be used to
2104 * specify things like line inversion semantics with the machine flags
2105 * such as GPIO_OUT_LOW
2106 * @dflags: descriptor request flags for this GPIO or 0 if default, this
2107 * can be used to specify consumer semantics such as open drain
2109 * Function allows GPIO chip drivers to request and use their own GPIO
2110 * descriptors via gpiolib API. Difference to gpiod_request() is that this
2111 * function will not increase reference count of the GPIO chip module. This
2112 * allows the GPIO chip module to be unloaded as needed (we assume that the
2113 * GPIO chip driver handles freeing the GPIOs it has requested).
2116 * A pointer to the GPIO descriptor, or an ERR_PTR()-encoded negative error
2119 struct gpio_desc *gpiochip_request_own_desc(struct gpio_chip *gc,
2122 enum gpio_lookup_flags lflags,
2123 enum gpiod_flags dflags)
2125 struct gpio_desc *desc = gpiochip_get_desc(gc, hwnum);
2129 chip_err(gc, "failed to get GPIO descriptor\n");
2133 ret = gpiod_request_commit(desc, label);
2135 return ERR_PTR(ret);
2137 ret = gpiod_configure_flags(desc, label, lflags, dflags);
2139 chip_err(gc, "setup of own GPIO %s failed\n", label);
2140 gpiod_free_commit(desc);
2141 return ERR_PTR(ret);
2146 EXPORT_SYMBOL_GPL(gpiochip_request_own_desc);
2149 * gpiochip_free_own_desc - Free GPIO requested by the chip driver
2150 * @desc: GPIO descriptor to free
2152 * Function frees the given GPIO requested previously with
2153 * gpiochip_request_own_desc().
2155 void gpiochip_free_own_desc(struct gpio_desc *desc)
2158 gpiod_free_commit(desc);
2160 EXPORT_SYMBOL_GPL(gpiochip_free_own_desc);
2163 * Drivers MUST set GPIO direction before making get/set calls. In
2164 * some cases this is done in early boot, before IRQs are enabled.
2166 * As a rule these aren't called more than once (except for drivers
2167 * using the open-drain emulation idiom) so these are natural places
2168 * to accumulate extra debugging checks. Note that we can't (yet)
2169 * rely on gpio_request() having been called beforehand.
2172 static int gpio_do_set_config(struct gpio_chip *gc, unsigned int offset,
2173 unsigned long config)
2175 if (!gc->set_config)
2178 return gc->set_config(gc, offset, config);
2181 static int gpio_set_config(struct gpio_desc *desc, enum pin_config_param mode)
2183 struct gpio_chip *gc = desc->gdev->chip;
2184 unsigned long config;
2188 case PIN_CONFIG_BIAS_PULL_DOWN:
2189 case PIN_CONFIG_BIAS_PULL_UP:
2197 config = PIN_CONF_PACKED(mode, arg);
2198 return gpio_do_set_config(gc, gpio_chip_hwgpio(desc), config);
2201 static int gpio_set_bias(struct gpio_desc *desc)
2206 if (test_bit(FLAG_BIAS_DISABLE, &desc->flags))
2207 bias = PIN_CONFIG_BIAS_DISABLE;
2208 else if (test_bit(FLAG_PULL_UP, &desc->flags))
2209 bias = PIN_CONFIG_BIAS_PULL_UP;
2210 else if (test_bit(FLAG_PULL_DOWN, &desc->flags))
2211 bias = PIN_CONFIG_BIAS_PULL_DOWN;
2214 ret = gpio_set_config(desc, bias);
2215 if (ret != -ENOTSUPP)
2222 * gpiod_direction_input - set the GPIO direction to input
2223 * @desc: GPIO to set to input
2225 * Set the direction of the passed GPIO to input, such as gpiod_get_value() can
2226 * be called safely on it.
2228 * Return 0 in case of success, else an error code.
2230 int gpiod_direction_input(struct gpio_desc *desc)
2232 struct gpio_chip *gc;
2235 VALIDATE_DESC(desc);
2236 gc = desc->gdev->chip;
2239 * It is legal to have no .get() and .direction_input() specified if
2240 * the chip is output-only, but you can't specify .direction_input()
2241 * and not support the .get() operation, that doesn't make sense.
2243 if (!gc->get && gc->direction_input) {
2245 "%s: missing get() but have direction_input()\n",
2251 * If we have a .direction_input() callback, things are simple,
2252 * just call it. Else we are some input-only chip so try to check the
2253 * direction (if .get_direction() is supported) else we silently
2254 * assume we are in input mode after this.
2256 if (gc->direction_input) {
2257 ret = gc->direction_input(gc, gpio_chip_hwgpio(desc));
2258 } else if (gc->get_direction &&
2259 (gc->get_direction(gc, gpio_chip_hwgpio(desc)) != 1)) {
2261 "%s: missing direction_input() operation and line is output\n",
2266 clear_bit(FLAG_IS_OUT, &desc->flags);
2267 ret = gpio_set_bias(desc);
2270 trace_gpio_direction(desc_to_gpio(desc), 1, ret);
2274 EXPORT_SYMBOL_GPL(gpiod_direction_input);
2276 static int gpiod_direction_output_raw_commit(struct gpio_desc *desc, int value)
2278 struct gpio_chip *gc = desc->gdev->chip;
2283 * It's OK not to specify .direction_output() if the gpiochip is
2284 * output-only, but if there is then not even a .set() operation it
2285 * is pretty tricky to drive the output line.
2287 if (!gc->set && !gc->direction_output) {
2289 "%s: missing set() and direction_output() operations\n",
2294 if (gc->direction_output) {
2295 ret = gc->direction_output(gc, gpio_chip_hwgpio(desc), val);
2297 /* Check that we are in output mode if we can */
2298 if (gc->get_direction &&
2299 gc->get_direction(gc, gpio_chip_hwgpio(desc))) {
2301 "%s: missing direction_output() operation\n",
2306 * If we can't actively set the direction, we are some
2307 * output-only chip, so just drive the output as desired.
2309 gc->set(gc, gpio_chip_hwgpio(desc), val);
2313 set_bit(FLAG_IS_OUT, &desc->flags);
2314 trace_gpio_value(desc_to_gpio(desc), 0, val);
2315 trace_gpio_direction(desc_to_gpio(desc), 0, ret);
2320 * gpiod_direction_output_raw - set the GPIO direction to output
2321 * @desc: GPIO to set to output
2322 * @value: initial output value of the GPIO
2324 * Set the direction of the passed GPIO to output, such as gpiod_set_value() can
2325 * be called safely on it. The initial value of the output must be specified
2326 * as raw value on the physical line without regard for the ACTIVE_LOW status.
2328 * Return 0 in case of success, else an error code.
2330 int gpiod_direction_output_raw(struct gpio_desc *desc, int value)
2332 VALIDATE_DESC(desc);
2333 return gpiod_direction_output_raw_commit(desc, value);
2335 EXPORT_SYMBOL_GPL(gpiod_direction_output_raw);
2338 * gpiod_direction_output - set the GPIO direction to output
2339 * @desc: GPIO to set to output
2340 * @value: initial output value of the GPIO
2342 * Set the direction of the passed GPIO to output, such as gpiod_set_value() can
2343 * be called safely on it. The initial value of the output must be specified
2344 * as the logical value of the GPIO, i.e. taking its ACTIVE_LOW status into
2347 * Return 0 in case of success, else an error code.
2349 int gpiod_direction_output(struct gpio_desc *desc, int value)
2353 VALIDATE_DESC(desc);
2354 if (test_bit(FLAG_ACTIVE_LOW, &desc->flags))
2359 /* GPIOs used for enabled IRQs shall not be set as output */
2360 if (test_bit(FLAG_USED_AS_IRQ, &desc->flags) &&
2361 test_bit(FLAG_IRQ_IS_ENABLED, &desc->flags)) {
2363 "%s: tried to set a GPIO tied to an IRQ as output\n",
2368 if (test_bit(FLAG_OPEN_DRAIN, &desc->flags)) {
2369 /* First see if we can enable open drain in hardware */
2370 ret = gpio_set_config(desc, PIN_CONFIG_DRIVE_OPEN_DRAIN);
2372 goto set_output_value;
2373 /* Emulate open drain by not actively driving the line high */
2375 ret = gpiod_direction_input(desc);
2376 goto set_output_flag;
2379 else if (test_bit(FLAG_OPEN_SOURCE, &desc->flags)) {
2380 ret = gpio_set_config(desc, PIN_CONFIG_DRIVE_OPEN_SOURCE);
2382 goto set_output_value;
2383 /* Emulate open source by not actively driving the line low */
2385 ret = gpiod_direction_input(desc);
2386 goto set_output_flag;
2389 gpio_set_config(desc, PIN_CONFIG_DRIVE_PUSH_PULL);
2393 ret = gpio_set_bias(desc);
2396 return gpiod_direction_output_raw_commit(desc, value);
2400 * When emulating open-source or open-drain functionalities by not
2401 * actively driving the line (setting mode to input) we still need to
2402 * set the IS_OUT flag or otherwise we won't be able to set the line
2406 set_bit(FLAG_IS_OUT, &desc->flags);
2409 EXPORT_SYMBOL_GPL(gpiod_direction_output);
2412 * gpiod_set_config - sets @config for a GPIO
2413 * @desc: descriptor of the GPIO for which to set the configuration
2414 * @config: Same packed config format as generic pinconf
2417 * 0 on success, %-ENOTSUPP if the controller doesn't support setting the
2420 int gpiod_set_config(struct gpio_desc *desc, unsigned long config)
2422 struct gpio_chip *gc;
2424 VALIDATE_DESC(desc);
2425 gc = desc->gdev->chip;
2427 return gpio_do_set_config(gc, gpio_chip_hwgpio(desc), config);
2429 EXPORT_SYMBOL_GPL(gpiod_set_config);
2432 * gpiod_set_debounce - sets @debounce time for a GPIO
2433 * @desc: descriptor of the GPIO for which to set debounce time
2434 * @debounce: debounce time in microseconds
2437 * 0 on success, %-ENOTSUPP if the controller doesn't support setting the
2440 int gpiod_set_debounce(struct gpio_desc *desc, unsigned debounce)
2442 unsigned long config;
2444 config = pinconf_to_config_packed(PIN_CONFIG_INPUT_DEBOUNCE, debounce);
2445 return gpiod_set_config(desc, config);
2447 EXPORT_SYMBOL_GPL(gpiod_set_debounce);
2450 * gpiod_set_transitory - Lose or retain GPIO state on suspend or reset
2451 * @desc: descriptor of the GPIO for which to configure persistence
2452 * @transitory: True to lose state on suspend or reset, false for persistence
2455 * 0 on success, otherwise a negative error code.
2457 int gpiod_set_transitory(struct gpio_desc *desc, bool transitory)
2459 struct gpio_chip *gc;
2460 unsigned long packed;
2464 VALIDATE_DESC(desc);
2466 * Handle FLAG_TRANSITORY first, enabling queries to gpiolib for
2467 * persistence state.
2469 assign_bit(FLAG_TRANSITORY, &desc->flags, transitory);
2471 /* If the driver supports it, set the persistence state now */
2472 gc = desc->gdev->chip;
2473 if (!gc->set_config)
2476 packed = pinconf_to_config_packed(PIN_CONFIG_PERSIST_STATE,
2478 gpio = gpio_chip_hwgpio(desc);
2479 rc = gpio_do_set_config(gc, gpio, packed);
2480 if (rc == -ENOTSUPP) {
2481 dev_dbg(&desc->gdev->dev, "Persistence not supported for GPIO %d\n",
2488 EXPORT_SYMBOL_GPL(gpiod_set_transitory);
2491 * gpiod_is_active_low - test whether a GPIO is active-low or not
2492 * @desc: the gpio descriptor to test
2494 * Returns 1 if the GPIO is active-low, 0 otherwise.
2496 int gpiod_is_active_low(const struct gpio_desc *desc)
2498 VALIDATE_DESC(desc);
2499 return test_bit(FLAG_ACTIVE_LOW, &desc->flags);
2501 EXPORT_SYMBOL_GPL(gpiod_is_active_low);
2504 * gpiod_toggle_active_low - toggle whether a GPIO is active-low or not
2505 * @desc: the gpio descriptor to change
2507 void gpiod_toggle_active_low(struct gpio_desc *desc)
2509 VALIDATE_DESC_VOID(desc);
2510 change_bit(FLAG_ACTIVE_LOW, &desc->flags);
2512 EXPORT_SYMBOL_GPL(gpiod_toggle_active_low);
2514 /* I/O calls are only valid after configuration completed; the relevant
2515 * "is this a valid GPIO" error checks should already have been done.
2517 * "Get" operations are often inlinable as reading a pin value register,
2518 * and masking the relevant bit in that register.
2520 * When "set" operations are inlinable, they involve writing that mask to
2521 * one register to set a low value, or a different register to set it high.
2522 * Otherwise locking is needed, so there may be little value to inlining.
2524 *------------------------------------------------------------------------
2526 * IMPORTANT!!! The hot paths -- get/set value -- assume that callers
2527 * have requested the GPIO. That can include implicit requesting by
2528 * a direction setting call. Marking a gpio as requested locks its chip
2529 * in memory, guaranteeing that these table lookups need no more locking
2530 * and that gpiochip_remove() will fail.
2532 * REVISIT when debugging, consider adding some instrumentation to ensure
2533 * that the GPIO was actually requested.
2536 static int gpiod_get_raw_value_commit(const struct gpio_desc *desc)
2538 struct gpio_chip *gc;
2542 gc = desc->gdev->chip;
2543 offset = gpio_chip_hwgpio(desc);
2544 value = gc->get ? gc->get(gc, offset) : -EIO;
2545 value = value < 0 ? value : !!value;
2546 trace_gpio_value(desc_to_gpio(desc), 1, value);
2550 static int gpio_chip_get_multiple(struct gpio_chip *gc,
2551 unsigned long *mask, unsigned long *bits)
2553 if (gc->get_multiple) {
2554 return gc->get_multiple(gc, mask, bits);
2555 } else if (gc->get) {
2558 for_each_set_bit(i, mask, gc->ngpio) {
2559 value = gc->get(gc, i);
2562 __assign_bit(i, bits, value);
2569 int gpiod_get_array_value_complex(bool raw, bool can_sleep,
2570 unsigned int array_size,
2571 struct gpio_desc **desc_array,
2572 struct gpio_array *array_info,
2573 unsigned long *value_bitmap)
2578 * Validate array_info against desc_array and its size.
2579 * It should immediately follow desc_array if both
2580 * have been obtained from the same gpiod_get_array() call.
2582 if (array_info && array_info->desc == desc_array &&
2583 array_size <= array_info->size &&
2584 (void *)array_info == desc_array + array_info->size) {
2586 WARN_ON(array_info->chip->can_sleep);
2588 ret = gpio_chip_get_multiple(array_info->chip,
2589 array_info->get_mask,
2594 if (!raw && !bitmap_empty(array_info->invert_mask, array_size))
2595 bitmap_xor(value_bitmap, value_bitmap,
2596 array_info->invert_mask, array_size);
2598 i = find_first_zero_bit(array_info->get_mask, array_size);
2599 if (i == array_size)
2605 while (i < array_size) {
2606 struct gpio_chip *gc = desc_array[i]->gdev->chip;
2607 unsigned long fastpath[2 * BITS_TO_LONGS(FASTPATH_NGPIO)];
2608 unsigned long *mask, *bits;
2611 if (likely(gc->ngpio <= FASTPATH_NGPIO)) {
2614 mask = kmalloc_array(2 * BITS_TO_LONGS(gc->ngpio),
2616 can_sleep ? GFP_KERNEL : GFP_ATOMIC);
2621 bits = mask + BITS_TO_LONGS(gc->ngpio);
2622 bitmap_zero(mask, gc->ngpio);
2625 WARN_ON(gc->can_sleep);
2627 /* collect all inputs belonging to the same chip */
2630 const struct gpio_desc *desc = desc_array[i];
2631 int hwgpio = gpio_chip_hwgpio(desc);
2633 __set_bit(hwgpio, mask);
2637 i = find_next_zero_bit(array_info->get_mask,
2639 } while ((i < array_size) &&
2640 (desc_array[i]->gdev->chip == gc));
2642 ret = gpio_chip_get_multiple(gc, mask, bits);
2644 if (mask != fastpath)
2649 for (j = first; j < i; ) {
2650 const struct gpio_desc *desc = desc_array[j];
2651 int hwgpio = gpio_chip_hwgpio(desc);
2652 int value = test_bit(hwgpio, bits);
2654 if (!raw && test_bit(FLAG_ACTIVE_LOW, &desc->flags))
2656 __assign_bit(j, value_bitmap, value);
2657 trace_gpio_value(desc_to_gpio(desc), 1, value);
2661 j = find_next_zero_bit(array_info->get_mask, i,
2665 if (mask != fastpath)
2672 * gpiod_get_raw_value() - return a gpio's raw value
2673 * @desc: gpio whose value will be returned
2675 * Return the GPIO's raw value, i.e. the value of the physical line disregarding
2676 * its ACTIVE_LOW status, or negative errno on failure.
2678 * This function can be called from contexts where we cannot sleep, and will
2679 * complain if the GPIO chip functions potentially sleep.
2681 int gpiod_get_raw_value(const struct gpio_desc *desc)
2683 VALIDATE_DESC(desc);
2684 /* Should be using gpiod_get_raw_value_cansleep() */
2685 WARN_ON(desc->gdev->chip->can_sleep);
2686 return gpiod_get_raw_value_commit(desc);
2688 EXPORT_SYMBOL_GPL(gpiod_get_raw_value);
2691 * gpiod_get_value() - return a gpio's value
2692 * @desc: gpio whose value will be returned
2694 * Return the GPIO's logical value, i.e. taking the ACTIVE_LOW status into
2695 * account, or negative errno on failure.
2697 * This function can be called from contexts where we cannot sleep, and will
2698 * complain if the GPIO chip functions potentially sleep.
2700 int gpiod_get_value(const struct gpio_desc *desc)
2704 VALIDATE_DESC(desc);
2705 /* Should be using gpiod_get_value_cansleep() */
2706 WARN_ON(desc->gdev->chip->can_sleep);
2708 value = gpiod_get_raw_value_commit(desc);
2712 if (test_bit(FLAG_ACTIVE_LOW, &desc->flags))
2717 EXPORT_SYMBOL_GPL(gpiod_get_value);
2720 * gpiod_get_raw_array_value() - read raw values from an array of GPIOs
2721 * @array_size: number of elements in the descriptor array / value bitmap
2722 * @desc_array: array of GPIO descriptors whose values will be read
2723 * @array_info: information on applicability of fast bitmap processing path
2724 * @value_bitmap: bitmap to store the read values
2726 * Read the raw values of the GPIOs, i.e. the values of the physical lines
2727 * without regard for their ACTIVE_LOW status. Return 0 in case of success,
2728 * else an error code.
2730 * This function can be called from contexts where we cannot sleep,
2731 * and it will complain if the GPIO chip functions potentially sleep.
2733 int gpiod_get_raw_array_value(unsigned int array_size,
2734 struct gpio_desc **desc_array,
2735 struct gpio_array *array_info,
2736 unsigned long *value_bitmap)
2740 return gpiod_get_array_value_complex(true, false, array_size,
2741 desc_array, array_info,
2744 EXPORT_SYMBOL_GPL(gpiod_get_raw_array_value);
2747 * gpiod_get_array_value() - read values from an array of GPIOs
2748 * @array_size: number of elements in the descriptor array / value bitmap
2749 * @desc_array: array of GPIO descriptors whose values will be read
2750 * @array_info: information on applicability of fast bitmap processing path
2751 * @value_bitmap: bitmap to store the read values
2753 * Read the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status
2754 * into account. Return 0 in case of success, else an error code.
2756 * This function can be called from contexts where we cannot sleep,
2757 * and it will complain if the GPIO chip functions potentially sleep.
2759 int gpiod_get_array_value(unsigned int array_size,
2760 struct gpio_desc **desc_array,
2761 struct gpio_array *array_info,
2762 unsigned long *value_bitmap)
2766 return gpiod_get_array_value_complex(false, false, array_size,
2767 desc_array, array_info,
2770 EXPORT_SYMBOL_GPL(gpiod_get_array_value);
2773 * gpio_set_open_drain_value_commit() - Set the open drain gpio's value.
2774 * @desc: gpio descriptor whose state need to be set.
2775 * @value: Non-zero for setting it HIGH otherwise it will set to LOW.
2777 static void gpio_set_open_drain_value_commit(struct gpio_desc *desc, bool value)
2780 struct gpio_chip *gc = desc->gdev->chip;
2781 int offset = gpio_chip_hwgpio(desc);
2784 ret = gc->direction_input(gc, offset);
2786 ret = gc->direction_output(gc, offset, 0);
2788 set_bit(FLAG_IS_OUT, &desc->flags);
2790 trace_gpio_direction(desc_to_gpio(desc), value, ret);
2793 "%s: Error in set_value for open drain err %d\n",
2798 * _gpio_set_open_source_value() - Set the open source gpio's value.
2799 * @desc: gpio descriptor whose state need to be set.
2800 * @value: Non-zero for setting it HIGH otherwise it will set to LOW.
2802 static void gpio_set_open_source_value_commit(struct gpio_desc *desc, bool value)
2805 struct gpio_chip *gc = desc->gdev->chip;
2806 int offset = gpio_chip_hwgpio(desc);
2809 ret = gc->direction_output(gc, offset, 1);
2811 set_bit(FLAG_IS_OUT, &desc->flags);
2813 ret = gc->direction_input(gc, offset);
2815 trace_gpio_direction(desc_to_gpio(desc), !value, ret);
2818 "%s: Error in set_value for open source err %d\n",
2822 static void gpiod_set_raw_value_commit(struct gpio_desc *desc, bool value)
2824 struct gpio_chip *gc;
2826 gc = desc->gdev->chip;
2827 trace_gpio_value(desc_to_gpio(desc), 0, value);
2828 gc->set(gc, gpio_chip_hwgpio(desc), value);
2832 * set multiple outputs on the same chip;
2833 * use the chip's set_multiple function if available;
2834 * otherwise set the outputs sequentially;
2835 * @chip: the GPIO chip we operate on
2836 * @mask: bit mask array; one bit per output; BITS_PER_LONG bits per word
2837 * defines which outputs are to be changed
2838 * @bits: bit value array; one bit per output; BITS_PER_LONG bits per word
2839 * defines the values the outputs specified by mask are to be set to
2841 static void gpio_chip_set_multiple(struct gpio_chip *gc,
2842 unsigned long *mask, unsigned long *bits)
2844 if (gc->set_multiple) {
2845 gc->set_multiple(gc, mask, bits);
2849 /* set outputs if the corresponding mask bit is set */
2850 for_each_set_bit(i, mask, gc->ngpio)
2851 gc->set(gc, i, test_bit(i, bits));
2855 int gpiod_set_array_value_complex(bool raw, bool can_sleep,
2856 unsigned int array_size,
2857 struct gpio_desc **desc_array,
2858 struct gpio_array *array_info,
2859 unsigned long *value_bitmap)
2864 * Validate array_info against desc_array and its size.
2865 * It should immediately follow desc_array if both
2866 * have been obtained from the same gpiod_get_array() call.
2868 if (array_info && array_info->desc == desc_array &&
2869 array_size <= array_info->size &&
2870 (void *)array_info == desc_array + array_info->size) {
2872 WARN_ON(array_info->chip->can_sleep);
2874 if (!raw && !bitmap_empty(array_info->invert_mask, array_size))
2875 bitmap_xor(value_bitmap, value_bitmap,
2876 array_info->invert_mask, array_size);
2878 gpio_chip_set_multiple(array_info->chip, array_info->set_mask,
2881 i = find_first_zero_bit(array_info->set_mask, array_size);
2882 if (i == array_size)
2888 while (i < array_size) {
2889 struct gpio_chip *gc = desc_array[i]->gdev->chip;
2890 unsigned long fastpath[2 * BITS_TO_LONGS(FASTPATH_NGPIO)];
2891 unsigned long *mask, *bits;
2894 if (likely(gc->ngpio <= FASTPATH_NGPIO)) {
2897 mask = kmalloc_array(2 * BITS_TO_LONGS(gc->ngpio),
2899 can_sleep ? GFP_KERNEL : GFP_ATOMIC);
2904 bits = mask + BITS_TO_LONGS(gc->ngpio);
2905 bitmap_zero(mask, gc->ngpio);
2908 WARN_ON(gc->can_sleep);
2911 struct gpio_desc *desc = desc_array[i];
2912 int hwgpio = gpio_chip_hwgpio(desc);
2913 int value = test_bit(i, value_bitmap);
2916 * Pins applicable for fast input but not for
2917 * fast output processing may have been already
2918 * inverted inside the fast path, skip them.
2920 if (!raw && !(array_info &&
2921 test_bit(i, array_info->invert_mask)) &&
2922 test_bit(FLAG_ACTIVE_LOW, &desc->flags))
2924 trace_gpio_value(desc_to_gpio(desc), 0, value);
2926 * collect all normal outputs belonging to the same chip
2927 * open drain and open source outputs are set individually
2929 if (test_bit(FLAG_OPEN_DRAIN, &desc->flags) && !raw) {
2930 gpio_set_open_drain_value_commit(desc, value);
2931 } else if (test_bit(FLAG_OPEN_SOURCE, &desc->flags) && !raw) {
2932 gpio_set_open_source_value_commit(desc, value);
2934 __set_bit(hwgpio, mask);
2935 __assign_bit(hwgpio, bits, value);
2941 i = find_next_zero_bit(array_info->set_mask,
2943 } while ((i < array_size) &&
2944 (desc_array[i]->gdev->chip == gc));
2945 /* push collected bits to outputs */
2947 gpio_chip_set_multiple(gc, mask, bits);
2949 if (mask != fastpath)
2956 * gpiod_set_raw_value() - assign a gpio's raw value
2957 * @desc: gpio whose value will be assigned
2958 * @value: value to assign
2960 * Set the raw value of the GPIO, i.e. the value of its physical line without
2961 * regard for its ACTIVE_LOW status.
2963 * This function can be called from contexts where we cannot sleep, and will
2964 * complain if the GPIO chip functions potentially sleep.
2966 void gpiod_set_raw_value(struct gpio_desc *desc, int value)
2968 VALIDATE_DESC_VOID(desc);
2969 /* Should be using gpiod_set_raw_value_cansleep() */
2970 WARN_ON(desc->gdev->chip->can_sleep);
2971 gpiod_set_raw_value_commit(desc, value);
2973 EXPORT_SYMBOL_GPL(gpiod_set_raw_value);
2976 * gpiod_set_value_nocheck() - set a GPIO line value without checking
2977 * @desc: the descriptor to set the value on
2978 * @value: value to set
2980 * This sets the value of a GPIO line backing a descriptor, applying
2981 * different semantic quirks like active low and open drain/source
2984 static void gpiod_set_value_nocheck(struct gpio_desc *desc, int value)
2986 if (test_bit(FLAG_ACTIVE_LOW, &desc->flags))
2988 if (test_bit(FLAG_OPEN_DRAIN, &desc->flags))
2989 gpio_set_open_drain_value_commit(desc, value);
2990 else if (test_bit(FLAG_OPEN_SOURCE, &desc->flags))
2991 gpio_set_open_source_value_commit(desc, value);
2993 gpiod_set_raw_value_commit(desc, value);
2997 * gpiod_set_value() - assign a gpio's value
2998 * @desc: gpio whose value will be assigned
2999 * @value: value to assign
3001 * Set the logical value of the GPIO, i.e. taking its ACTIVE_LOW,
3002 * OPEN_DRAIN and OPEN_SOURCE flags into account.
3004 * This function can be called from contexts where we cannot sleep, and will
3005 * complain if the GPIO chip functions potentially sleep.
3007 void gpiod_set_value(struct gpio_desc *desc, int value)
3009 VALIDATE_DESC_VOID(desc);
3010 /* Should be using gpiod_set_value_cansleep() */
3011 WARN_ON(desc->gdev->chip->can_sleep);
3012 gpiod_set_value_nocheck(desc, value);
3014 EXPORT_SYMBOL_GPL(gpiod_set_value);
3017 * gpiod_set_raw_array_value() - assign values to an array of GPIOs
3018 * @array_size: number of elements in the descriptor array / value bitmap
3019 * @desc_array: array of GPIO descriptors whose values will be assigned
3020 * @array_info: information on applicability of fast bitmap processing path
3021 * @value_bitmap: bitmap of values to assign
3023 * Set the raw values of the GPIOs, i.e. the values of the physical lines
3024 * without regard for their ACTIVE_LOW status.
3026 * This function can be called from contexts where we cannot sleep, and will
3027 * complain if the GPIO chip functions potentially sleep.
3029 int gpiod_set_raw_array_value(unsigned int array_size,
3030 struct gpio_desc **desc_array,
3031 struct gpio_array *array_info,
3032 unsigned long *value_bitmap)
3036 return gpiod_set_array_value_complex(true, false, array_size,
3037 desc_array, array_info, value_bitmap);
3039 EXPORT_SYMBOL_GPL(gpiod_set_raw_array_value);
3042 * gpiod_set_array_value() - assign values to an array of GPIOs
3043 * @array_size: number of elements in the descriptor array / value bitmap
3044 * @desc_array: array of GPIO descriptors whose values will be assigned
3045 * @array_info: information on applicability of fast bitmap processing path
3046 * @value_bitmap: bitmap of values to assign
3048 * Set the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status
3051 * This function can be called from contexts where we cannot sleep, and will
3052 * complain if the GPIO chip functions potentially sleep.
3054 int gpiod_set_array_value(unsigned int array_size,
3055 struct gpio_desc **desc_array,
3056 struct gpio_array *array_info,
3057 unsigned long *value_bitmap)
3061 return gpiod_set_array_value_complex(false, false, array_size,
3062 desc_array, array_info,
3065 EXPORT_SYMBOL_GPL(gpiod_set_array_value);
3068 * gpiod_cansleep() - report whether gpio value access may sleep
3069 * @desc: gpio to check
3072 int gpiod_cansleep(const struct gpio_desc *desc)
3074 VALIDATE_DESC(desc);
3075 return desc->gdev->chip->can_sleep;
3077 EXPORT_SYMBOL_GPL(gpiod_cansleep);
3080 * gpiod_set_consumer_name() - set the consumer name for the descriptor
3081 * @desc: gpio to set the consumer name on
3082 * @name: the new consumer name
3084 int gpiod_set_consumer_name(struct gpio_desc *desc, const char *name)
3086 VALIDATE_DESC(desc);
3088 name = kstrdup_const(name, GFP_KERNEL);
3093 kfree_const(desc->label);
3094 desc_set_label(desc, name);
3098 EXPORT_SYMBOL_GPL(gpiod_set_consumer_name);
3101 * gpiod_to_irq() - return the IRQ corresponding to a GPIO
3102 * @desc: gpio whose IRQ will be returned (already requested)
3104 * Return the IRQ corresponding to the passed GPIO, or an error code in case of
3107 int gpiod_to_irq(const struct gpio_desc *desc)
3109 struct gpio_chip *gc;
3113 * Cannot VALIDATE_DESC() here as gpiod_to_irq() consumer semantics
3114 * requires this function to not return zero on an invalid descriptor
3115 * but rather a negative error number.
3117 if (!desc || IS_ERR(desc) || !desc->gdev || !desc->gdev->chip)
3120 gc = desc->gdev->chip;
3121 offset = gpio_chip_hwgpio(desc);
3123 int retirq = gc->to_irq(gc, offset);
3125 /* Zero means NO_IRQ */
3133 EXPORT_SYMBOL_GPL(gpiod_to_irq);
3136 * gpiochip_lock_as_irq() - lock a GPIO to be used as IRQ
3137 * @gc: the chip the GPIO to lock belongs to
3138 * @offset: the offset of the GPIO to lock as IRQ
3140 * This is used directly by GPIO drivers that want to lock down
3141 * a certain GPIO line to be used for IRQs.
3143 int gpiochip_lock_as_irq(struct gpio_chip *gc, unsigned int offset)
3145 struct gpio_desc *desc;
3147 desc = gpiochip_get_desc(gc, offset);
3149 return PTR_ERR(desc);
3152 * If it's fast: flush the direction setting if something changed
3155 if (!gc->can_sleep && gc->get_direction) {
3156 int dir = gpiod_get_direction(desc);
3159 chip_err(gc, "%s: cannot get GPIO direction\n",
3165 /* To be valid for IRQ the line needs to be input or open drain */
3166 if (test_bit(FLAG_IS_OUT, &desc->flags) &&
3167 !test_bit(FLAG_OPEN_DRAIN, &desc->flags)) {
3169 "%s: tried to flag a GPIO set as output for IRQ\n",
3174 set_bit(FLAG_USED_AS_IRQ, &desc->flags);
3175 set_bit(FLAG_IRQ_IS_ENABLED, &desc->flags);
3178 * If the consumer has not set up a label (such as when the
3179 * IRQ is referenced from .to_irq()) we set up a label here
3180 * so it is clear this is used as an interrupt.
3183 desc_set_label(desc, "interrupt");
3187 EXPORT_SYMBOL_GPL(gpiochip_lock_as_irq);
3190 * gpiochip_unlock_as_irq() - unlock a GPIO used as IRQ
3191 * @gc: the chip the GPIO to lock belongs to
3192 * @offset: the offset of the GPIO to lock as IRQ
3194 * This is used directly by GPIO drivers that want to indicate
3195 * that a certain GPIO is no longer used exclusively for IRQ.
3197 void gpiochip_unlock_as_irq(struct gpio_chip *gc, unsigned int offset)
3199 struct gpio_desc *desc;
3201 desc = gpiochip_get_desc(gc, offset);
3205 clear_bit(FLAG_USED_AS_IRQ, &desc->flags);
3206 clear_bit(FLAG_IRQ_IS_ENABLED, &desc->flags);
3208 /* If we only had this marking, erase it */
3209 if (desc->label && !strcmp(desc->label, "interrupt"))
3210 desc_set_label(desc, NULL);
3212 EXPORT_SYMBOL_GPL(gpiochip_unlock_as_irq);
3214 void gpiochip_disable_irq(struct gpio_chip *gc, unsigned int offset)
3216 struct gpio_desc *desc = gpiochip_get_desc(gc, offset);
3218 if (!IS_ERR(desc) &&
3219 !WARN_ON(!test_bit(FLAG_USED_AS_IRQ, &desc->flags)))
3220 clear_bit(FLAG_IRQ_IS_ENABLED, &desc->flags);
3222 EXPORT_SYMBOL_GPL(gpiochip_disable_irq);
3224 void gpiochip_enable_irq(struct gpio_chip *gc, unsigned int offset)
3226 struct gpio_desc *desc = gpiochip_get_desc(gc, offset);
3228 if (!IS_ERR(desc) &&
3229 !WARN_ON(!test_bit(FLAG_USED_AS_IRQ, &desc->flags))) {
3231 * We must not be output when using IRQ UNLESS we are
3234 WARN_ON(test_bit(FLAG_IS_OUT, &desc->flags) &&
3235 !test_bit(FLAG_OPEN_DRAIN, &desc->flags));
3236 set_bit(FLAG_IRQ_IS_ENABLED, &desc->flags);
3239 EXPORT_SYMBOL_GPL(gpiochip_enable_irq);
3241 bool gpiochip_line_is_irq(struct gpio_chip *gc, unsigned int offset)
3243 if (offset >= gc->ngpio)
3246 return test_bit(FLAG_USED_AS_IRQ, &gc->gpiodev->descs[offset].flags);
3248 EXPORT_SYMBOL_GPL(gpiochip_line_is_irq);
3250 int gpiochip_reqres_irq(struct gpio_chip *gc, unsigned int offset)
3254 if (!try_module_get(gc->gpiodev->owner))
3257 ret = gpiochip_lock_as_irq(gc, offset);
3259 chip_err(gc, "unable to lock HW IRQ %u for IRQ\n", offset);
3260 module_put(gc->gpiodev->owner);
3265 EXPORT_SYMBOL_GPL(gpiochip_reqres_irq);
3267 void gpiochip_relres_irq(struct gpio_chip *gc, unsigned int offset)
3269 gpiochip_unlock_as_irq(gc, offset);
3270 module_put(gc->gpiodev->owner);
3272 EXPORT_SYMBOL_GPL(gpiochip_relres_irq);
3274 bool gpiochip_line_is_open_drain(struct gpio_chip *gc, unsigned int offset)
3276 if (offset >= gc->ngpio)
3279 return test_bit(FLAG_OPEN_DRAIN, &gc->gpiodev->descs[offset].flags);
3281 EXPORT_SYMBOL_GPL(gpiochip_line_is_open_drain);
3283 bool gpiochip_line_is_open_source(struct gpio_chip *gc, unsigned int offset)
3285 if (offset >= gc->ngpio)
3288 return test_bit(FLAG_OPEN_SOURCE, &gc->gpiodev->descs[offset].flags);
3290 EXPORT_SYMBOL_GPL(gpiochip_line_is_open_source);
3292 bool gpiochip_line_is_persistent(struct gpio_chip *gc, unsigned int offset)
3294 if (offset >= gc->ngpio)
3297 return !test_bit(FLAG_TRANSITORY, &gc->gpiodev->descs[offset].flags);
3299 EXPORT_SYMBOL_GPL(gpiochip_line_is_persistent);
3302 * gpiod_get_raw_value_cansleep() - return a gpio's raw value
3303 * @desc: gpio whose value will be returned
3305 * Return the GPIO's raw value, i.e. the value of the physical line disregarding
3306 * its ACTIVE_LOW status, or negative errno on failure.
3308 * This function is to be called from contexts that can sleep.
3310 int gpiod_get_raw_value_cansleep(const struct gpio_desc *desc)
3312 might_sleep_if(extra_checks);
3313 VALIDATE_DESC(desc);
3314 return gpiod_get_raw_value_commit(desc);
3316 EXPORT_SYMBOL_GPL(gpiod_get_raw_value_cansleep);
3319 * gpiod_get_value_cansleep() - return a gpio's value
3320 * @desc: gpio whose value will be returned
3322 * Return the GPIO's logical value, i.e. taking the ACTIVE_LOW status into
3323 * account, or negative errno on failure.
3325 * This function is to be called from contexts that can sleep.
3327 int gpiod_get_value_cansleep(const struct gpio_desc *desc)
3331 might_sleep_if(extra_checks);
3332 VALIDATE_DESC(desc);
3333 value = gpiod_get_raw_value_commit(desc);
3337 if (test_bit(FLAG_ACTIVE_LOW, &desc->flags))
3342 EXPORT_SYMBOL_GPL(gpiod_get_value_cansleep);
3345 * gpiod_get_raw_array_value_cansleep() - read raw values from an array of GPIOs
3346 * @array_size: number of elements in the descriptor array / value bitmap
3347 * @desc_array: array of GPIO descriptors whose values will be read
3348 * @array_info: information on applicability of fast bitmap processing path
3349 * @value_bitmap: bitmap to store the read values
3351 * Read the raw values of the GPIOs, i.e. the values of the physical lines
3352 * without regard for their ACTIVE_LOW status. Return 0 in case of success,
3353 * else an error code.
3355 * This function is to be called from contexts that can sleep.
3357 int gpiod_get_raw_array_value_cansleep(unsigned int array_size,
3358 struct gpio_desc **desc_array,
3359 struct gpio_array *array_info,
3360 unsigned long *value_bitmap)
3362 might_sleep_if(extra_checks);
3365 return gpiod_get_array_value_complex(true, true, array_size,
3366 desc_array, array_info,
3369 EXPORT_SYMBOL_GPL(gpiod_get_raw_array_value_cansleep);
3372 * gpiod_get_array_value_cansleep() - read values from an array of GPIOs
3373 * @array_size: number of elements in the descriptor array / value bitmap
3374 * @desc_array: array of GPIO descriptors whose values will be read
3375 * @array_info: information on applicability of fast bitmap processing path
3376 * @value_bitmap: bitmap to store the read values
3378 * Read the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status
3379 * into account. Return 0 in case of success, else an error code.
3381 * This function is to be called from contexts that can sleep.
3383 int gpiod_get_array_value_cansleep(unsigned int array_size,
3384 struct gpio_desc **desc_array,
3385 struct gpio_array *array_info,
3386 unsigned long *value_bitmap)
3388 might_sleep_if(extra_checks);
3391 return gpiod_get_array_value_complex(false, true, array_size,
3392 desc_array, array_info,
3395 EXPORT_SYMBOL_GPL(gpiod_get_array_value_cansleep);
3398 * gpiod_set_raw_value_cansleep() - assign a gpio's raw value
3399 * @desc: gpio whose value will be assigned
3400 * @value: value to assign
3402 * Set the raw value of the GPIO, i.e. the value of its physical line without
3403 * regard for its ACTIVE_LOW status.
3405 * This function is to be called from contexts that can sleep.
3407 void gpiod_set_raw_value_cansleep(struct gpio_desc *desc, int value)
3409 might_sleep_if(extra_checks);
3410 VALIDATE_DESC_VOID(desc);
3411 gpiod_set_raw_value_commit(desc, value);
3413 EXPORT_SYMBOL_GPL(gpiod_set_raw_value_cansleep);
3416 * gpiod_set_value_cansleep() - assign a gpio's value
3417 * @desc: gpio whose value will be assigned
3418 * @value: value to assign
3420 * Set the logical value of the GPIO, i.e. taking its ACTIVE_LOW status into
3423 * This function is to be called from contexts that can sleep.
3425 void gpiod_set_value_cansleep(struct gpio_desc *desc, int value)
3427 might_sleep_if(extra_checks);
3428 VALIDATE_DESC_VOID(desc);
3429 gpiod_set_value_nocheck(desc, value);
3431 EXPORT_SYMBOL_GPL(gpiod_set_value_cansleep);
3434 * gpiod_set_raw_array_value_cansleep() - assign values to an array of GPIOs
3435 * @array_size: number of elements in the descriptor array / value bitmap
3436 * @desc_array: array of GPIO descriptors whose values will be assigned
3437 * @array_info: information on applicability of fast bitmap processing path
3438 * @value_bitmap: bitmap of values to assign
3440 * Set the raw values of the GPIOs, i.e. the values of the physical lines
3441 * without regard for their ACTIVE_LOW status.
3443 * This function is to be called from contexts that can sleep.
3445 int gpiod_set_raw_array_value_cansleep(unsigned int array_size,
3446 struct gpio_desc **desc_array,
3447 struct gpio_array *array_info,
3448 unsigned long *value_bitmap)
3450 might_sleep_if(extra_checks);
3453 return gpiod_set_array_value_complex(true, true, array_size, desc_array,
3454 array_info, value_bitmap);
3456 EXPORT_SYMBOL_GPL(gpiod_set_raw_array_value_cansleep);
3459 * gpiod_add_lookup_tables() - register GPIO device consumers
3460 * @tables: list of tables of consumers to register
3461 * @n: number of tables in the list
3463 void gpiod_add_lookup_tables(struct gpiod_lookup_table **tables, size_t n)
3467 mutex_lock(&gpio_lookup_lock);
3469 for (i = 0; i < n; i++)
3470 list_add_tail(&tables[i]->list, &gpio_lookup_list);
3472 mutex_unlock(&gpio_lookup_lock);
3476 * gpiod_set_array_value_cansleep() - assign values to an array of GPIOs
3477 * @array_size: number of elements in the descriptor array / value bitmap
3478 * @desc_array: array of GPIO descriptors whose values will be assigned
3479 * @array_info: information on applicability of fast bitmap processing path
3480 * @value_bitmap: bitmap of values to assign
3482 * Set the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status
3485 * This function is to be called from contexts that can sleep.
3487 int gpiod_set_array_value_cansleep(unsigned int array_size,
3488 struct gpio_desc **desc_array,
3489 struct gpio_array *array_info,
3490 unsigned long *value_bitmap)
3492 might_sleep_if(extra_checks);
3495 return gpiod_set_array_value_complex(false, true, array_size,
3496 desc_array, array_info,
3499 EXPORT_SYMBOL_GPL(gpiod_set_array_value_cansleep);
3502 * gpiod_add_lookup_table() - register GPIO device consumers
3503 * @table: table of consumers to register
3505 void gpiod_add_lookup_table(struct gpiod_lookup_table *table)
3507 mutex_lock(&gpio_lookup_lock);
3509 list_add_tail(&table->list, &gpio_lookup_list);
3511 mutex_unlock(&gpio_lookup_lock);
3513 EXPORT_SYMBOL_GPL(gpiod_add_lookup_table);
3516 * gpiod_remove_lookup_table() - unregister GPIO device consumers
3517 * @table: table of consumers to unregister
3519 void gpiod_remove_lookup_table(struct gpiod_lookup_table *table)
3521 mutex_lock(&gpio_lookup_lock);
3523 list_del(&table->list);
3525 mutex_unlock(&gpio_lookup_lock);
3527 EXPORT_SYMBOL_GPL(gpiod_remove_lookup_table);
3530 * gpiod_add_hogs() - register a set of GPIO hogs from machine code
3531 * @hogs: table of gpio hog entries with a zeroed sentinel at the end
3533 void gpiod_add_hogs(struct gpiod_hog *hogs)
3535 struct gpio_chip *gc;
3536 struct gpiod_hog *hog;
3538 mutex_lock(&gpio_machine_hogs_mutex);
3540 for (hog = &hogs[0]; hog->chip_label; hog++) {
3541 list_add_tail(&hog->list, &gpio_machine_hogs);
3544 * The chip may have been registered earlier, so check if it
3545 * exists and, if so, try to hog the line now.
3547 gc = find_chip_by_name(hog->chip_label);
3549 gpiochip_machine_hog(gc, hog);
3552 mutex_unlock(&gpio_machine_hogs_mutex);
3554 EXPORT_SYMBOL_GPL(gpiod_add_hogs);
3556 static struct gpiod_lookup_table *gpiod_find_lookup_table(struct device *dev)
3558 const char *dev_id = dev ? dev_name(dev) : NULL;
3559 struct gpiod_lookup_table *table;
3561 mutex_lock(&gpio_lookup_lock);
3563 list_for_each_entry(table, &gpio_lookup_list, list) {
3564 if (table->dev_id && dev_id) {
3566 * Valid strings on both ends, must be identical to have
3569 if (!strcmp(table->dev_id, dev_id))
3573 * One of the pointers is NULL, so both must be to have
3576 if (dev_id == table->dev_id)
3583 mutex_unlock(&gpio_lookup_lock);
3587 static struct gpio_desc *gpiod_find(struct device *dev, const char *con_id,
3588 unsigned int idx, unsigned long *flags)
3590 struct gpio_desc *desc = ERR_PTR(-ENOENT);
3591 struct gpiod_lookup_table *table;
3592 struct gpiod_lookup *p;
3594 table = gpiod_find_lookup_table(dev);
3598 for (p = &table->table[0]; p->key; p++) {
3599 struct gpio_chip *gc;
3601 /* idx must always match exactly */
3605 /* If the lookup entry has a con_id, require exact match */
3606 if (p->con_id && (!con_id || strcmp(p->con_id, con_id)))
3609 if (p->chip_hwnum == U16_MAX) {
3610 desc = gpio_name_to_desc(p->key);
3616 dev_warn(dev, "cannot find GPIO line %s, deferring\n",
3618 return ERR_PTR(-EPROBE_DEFER);
3621 gc = find_chip_by_name(p->key);
3625 * As the lookup table indicates a chip with
3626 * p->key should exist, assume it may
3627 * still appear later and let the interested
3628 * consumer be probed again or let the Deferred
3629 * Probe infrastructure handle the error.
3631 dev_warn(dev, "cannot find GPIO chip %s, deferring\n",
3633 return ERR_PTR(-EPROBE_DEFER);
3636 if (gc->ngpio <= p->chip_hwnum) {
3638 "requested GPIO %u (%u) is out of range [0..%u] for chip %s\n",
3639 idx, p->chip_hwnum, gc->ngpio - 1,
3641 return ERR_PTR(-EINVAL);
3644 desc = gpiochip_get_desc(gc, p->chip_hwnum);
3653 static int platform_gpio_count(struct device *dev, const char *con_id)
3655 struct gpiod_lookup_table *table;
3656 struct gpiod_lookup *p;
3657 unsigned int count = 0;
3659 table = gpiod_find_lookup_table(dev);
3663 for (p = &table->table[0]; p->key; p++) {
3664 if ((con_id && p->con_id && !strcmp(con_id, p->con_id)) ||
3665 (!con_id && !p->con_id))
3675 * fwnode_gpiod_get_index - obtain a GPIO from firmware node
3676 * @fwnode: handle of the firmware node
3677 * @con_id: function within the GPIO consumer
3678 * @index: index of the GPIO to obtain for the consumer
3679 * @flags: GPIO initialization flags
3680 * @label: label to attach to the requested GPIO
3682 * This function can be used for drivers that get their configuration
3683 * from opaque firmware.
3685 * The function properly finds the corresponding GPIO using whatever is the
3686 * underlying firmware interface and then makes sure that the GPIO
3687 * descriptor is requested before it is returned to the caller.
3690 * On successful request the GPIO pin is configured in accordance with
3693 * In case of error an ERR_PTR() is returned.
3695 struct gpio_desc *fwnode_gpiod_get_index(struct fwnode_handle *fwnode,
3696 const char *con_id, int index,
3697 enum gpiod_flags flags,
3700 struct gpio_desc *desc;
3701 char prop_name[32]; /* 32 is max size of property name */
3704 for (i = 0; i < ARRAY_SIZE(gpio_suffixes); i++) {
3706 snprintf(prop_name, sizeof(prop_name), "%s-%s",
3707 con_id, gpio_suffixes[i]);
3709 snprintf(prop_name, sizeof(prop_name), "%s",
3712 desc = fwnode_get_named_gpiod(fwnode, prop_name, index, flags,
3714 if (!IS_ERR(desc) || (PTR_ERR(desc) != -ENOENT))
3720 EXPORT_SYMBOL_GPL(fwnode_gpiod_get_index);
3723 * gpiod_count - return the number of GPIOs associated with a device / function
3724 * or -ENOENT if no GPIO has been assigned to the requested function
3725 * @dev: GPIO consumer, can be NULL for system-global GPIOs
3726 * @con_id: function within the GPIO consumer
3728 int gpiod_count(struct device *dev, const char *con_id)
3730 int count = -ENOENT;
3732 if (IS_ENABLED(CONFIG_OF) && dev && dev->of_node)
3733 count = of_gpio_get_count(dev, con_id);
3734 else if (IS_ENABLED(CONFIG_ACPI) && dev && ACPI_HANDLE(dev))
3735 count = acpi_gpio_count(dev, con_id);
3738 count = platform_gpio_count(dev, con_id);
3742 EXPORT_SYMBOL_GPL(gpiod_count);
3745 * gpiod_get - obtain a GPIO for a given GPIO function
3746 * @dev: GPIO consumer, can be NULL for system-global GPIOs
3747 * @con_id: function within the GPIO consumer
3748 * @flags: optional GPIO initialization flags
3750 * Return the GPIO descriptor corresponding to the function con_id of device
3751 * dev, -ENOENT if no GPIO has been assigned to the requested function, or
3752 * another IS_ERR() code if an error occurred while trying to acquire the GPIO.
3754 struct gpio_desc *__must_check gpiod_get(struct device *dev, const char *con_id,
3755 enum gpiod_flags flags)
3757 return gpiod_get_index(dev, con_id, 0, flags);
3759 EXPORT_SYMBOL_GPL(gpiod_get);
3762 * gpiod_get_optional - obtain an optional GPIO for a given GPIO function
3763 * @dev: GPIO consumer, can be NULL for system-global GPIOs
3764 * @con_id: function within the GPIO consumer
3765 * @flags: optional GPIO initialization flags
3767 * This is equivalent to gpiod_get(), except that when no GPIO was assigned to
3768 * the requested function it will return NULL. This is convenient for drivers
3769 * that need to handle optional GPIOs.
3771 struct gpio_desc *__must_check gpiod_get_optional(struct device *dev,
3773 enum gpiod_flags flags)
3775 return gpiod_get_index_optional(dev, con_id, 0, flags);
3777 EXPORT_SYMBOL_GPL(gpiod_get_optional);
3781 * gpiod_configure_flags - helper function to configure a given GPIO
3782 * @desc: gpio whose value will be assigned
3783 * @con_id: function within the GPIO consumer
3784 * @lflags: bitmask of gpio_lookup_flags GPIO_* values - returned from
3785 * of_find_gpio() or of_get_gpio_hog()
3786 * @dflags: gpiod_flags - optional GPIO initialization flags
3788 * Return 0 on success, -ENOENT if no GPIO has been assigned to the
3789 * requested function and/or index, or another IS_ERR() code if an error
3790 * occurred while trying to acquire the GPIO.
3792 int gpiod_configure_flags(struct gpio_desc *desc, const char *con_id,
3793 unsigned long lflags, enum gpiod_flags dflags)
3797 if (lflags & GPIO_ACTIVE_LOW)
3798 set_bit(FLAG_ACTIVE_LOW, &desc->flags);
3800 if (lflags & GPIO_OPEN_DRAIN)
3801 set_bit(FLAG_OPEN_DRAIN, &desc->flags);
3802 else if (dflags & GPIOD_FLAGS_BIT_OPEN_DRAIN) {
3804 * This enforces open drain mode from the consumer side.
3805 * This is necessary for some busses like I2C, but the lookup
3806 * should *REALLY* have specified them as open drain in the
3807 * first place, so print a little warning here.
3809 set_bit(FLAG_OPEN_DRAIN, &desc->flags);
3811 "enforced open drain please flag it properly in DT/ACPI DSDT/board file\n");
3814 if (lflags & GPIO_OPEN_SOURCE)
3815 set_bit(FLAG_OPEN_SOURCE, &desc->flags);
3817 if ((lflags & GPIO_PULL_UP) && (lflags & GPIO_PULL_DOWN)) {
3819 "both pull-up and pull-down enabled, invalid configuration\n");
3823 if (lflags & GPIO_PULL_UP)
3824 set_bit(FLAG_PULL_UP, &desc->flags);
3825 else if (lflags & GPIO_PULL_DOWN)
3826 set_bit(FLAG_PULL_DOWN, &desc->flags);
3828 ret = gpiod_set_transitory(desc, (lflags & GPIO_TRANSITORY));
3832 /* No particular flag request, return here... */
3833 if (!(dflags & GPIOD_FLAGS_BIT_DIR_SET)) {
3834 gpiod_dbg(desc, "no flags found for %s\n", con_id);
3839 if (dflags & GPIOD_FLAGS_BIT_DIR_OUT)
3840 ret = gpiod_direction_output(desc,
3841 !!(dflags & GPIOD_FLAGS_BIT_DIR_VAL));
3843 ret = gpiod_direction_input(desc);
3849 * gpiod_get_index - obtain a GPIO from a multi-index GPIO function
3850 * @dev: GPIO consumer, can be NULL for system-global GPIOs
3851 * @con_id: function within the GPIO consumer
3852 * @idx: index of the GPIO to obtain in the consumer
3853 * @flags: optional GPIO initialization flags
3855 * This variant of gpiod_get() allows to access GPIOs other than the first
3856 * defined one for functions that define several GPIOs.
3858 * Return a valid GPIO descriptor, -ENOENT if no GPIO has been assigned to the
3859 * requested function and/or index, or another IS_ERR() code if an error
3860 * occurred while trying to acquire the GPIO.
3862 struct gpio_desc *__must_check gpiod_get_index(struct device *dev,
3865 enum gpiod_flags flags)
3867 unsigned long lookupflags = GPIO_LOOKUP_FLAGS_DEFAULT;
3868 struct gpio_desc *desc = NULL;
3870 /* Maybe we have a device name, maybe not */
3871 const char *devname = dev ? dev_name(dev) : "?";
3873 dev_dbg(dev, "GPIO lookup for consumer %s\n", con_id);
3876 /* Using device tree? */
3877 if (IS_ENABLED(CONFIG_OF) && dev->of_node) {
3878 dev_dbg(dev, "using device tree for GPIO lookup\n");
3879 desc = of_find_gpio(dev, con_id, idx, &lookupflags);
3880 } else if (ACPI_COMPANION(dev)) {
3881 dev_dbg(dev, "using ACPI for GPIO lookup\n");
3882 desc = acpi_find_gpio(dev, con_id, idx, &flags, &lookupflags);
3887 * Either we are not using DT or ACPI, or their lookup did not return
3888 * a result. In that case, use platform lookup as a fallback.
3890 if (!desc || desc == ERR_PTR(-ENOENT)) {
3891 dev_dbg(dev, "using lookup tables for GPIO lookup\n");
3892 desc = gpiod_find(dev, con_id, idx, &lookupflags);
3896 dev_dbg(dev, "No GPIO consumer %s found\n", con_id);
3901 * If a connection label was passed use that, else attempt to use
3902 * the device name as label
3904 ret = gpiod_request(desc, con_id ? con_id : devname);
3906 if (ret == -EBUSY && flags & GPIOD_FLAGS_BIT_NONEXCLUSIVE) {
3908 * This happens when there are several consumers for
3909 * the same GPIO line: we just return here without
3910 * further initialization. It is a bit if a hack.
3911 * This is necessary to support fixed regulators.
3913 * FIXME: Make this more sane and safe.
3915 dev_info(dev, "nonexclusive access to GPIO for %s\n",
3916 con_id ? con_id : devname);
3919 return ERR_PTR(ret);
3923 ret = gpiod_configure_flags(desc, con_id, lookupflags, flags);
3925 dev_dbg(dev, "setup of GPIO %s failed\n", con_id);
3927 return ERR_PTR(ret);
3930 blocking_notifier_call_chain(&desc->gdev->notifier,
3931 GPIOLINE_CHANGED_REQUESTED, desc);
3935 EXPORT_SYMBOL_GPL(gpiod_get_index);
3938 * fwnode_get_named_gpiod - obtain a GPIO from firmware node
3939 * @fwnode: handle of the firmware node
3940 * @propname: name of the firmware property representing the GPIO
3941 * @index: index of the GPIO to obtain for the consumer
3942 * @dflags: GPIO initialization flags
3943 * @label: label to attach to the requested GPIO
3945 * This function can be used for drivers that get their configuration
3946 * from opaque firmware.
3948 * The function properly finds the corresponding GPIO using whatever is the
3949 * underlying firmware interface and then makes sure that the GPIO
3950 * descriptor is requested before it is returned to the caller.
3953 * On successful request the GPIO pin is configured in accordance with
3956 * In case of error an ERR_PTR() is returned.
3958 struct gpio_desc *fwnode_get_named_gpiod(struct fwnode_handle *fwnode,
3959 const char *propname, int index,
3960 enum gpiod_flags dflags,
3963 unsigned long lflags = GPIO_LOOKUP_FLAGS_DEFAULT;
3964 struct gpio_desc *desc = ERR_PTR(-ENODEV);
3968 return ERR_PTR(-EINVAL);
3970 if (is_of_node(fwnode)) {
3971 desc = gpiod_get_from_of_node(to_of_node(fwnode),
3976 } else if (is_acpi_node(fwnode)) {
3977 struct acpi_gpio_info info;
3979 desc = acpi_node_get_gpiod(fwnode, propname, index, &info);
3983 acpi_gpio_update_gpiod_flags(&dflags, &info);
3984 acpi_gpio_update_gpiod_lookup_flags(&lflags, &info);
3987 /* Currently only ACPI takes this path */
3988 ret = gpiod_request(desc, label);
3990 return ERR_PTR(ret);
3992 ret = gpiod_configure_flags(desc, propname, lflags, dflags);
3995 return ERR_PTR(ret);
3998 blocking_notifier_call_chain(&desc->gdev->notifier,
3999 GPIOLINE_CHANGED_REQUESTED, desc);
4003 EXPORT_SYMBOL_GPL(fwnode_get_named_gpiod);
4006 * gpiod_get_index_optional - obtain an optional GPIO from a multi-index GPIO
4008 * @dev: GPIO consumer, can be NULL for system-global GPIOs
4009 * @con_id: function within the GPIO consumer
4010 * @index: index of the GPIO to obtain in the consumer
4011 * @flags: optional GPIO initialization flags
4013 * This is equivalent to gpiod_get_index(), except that when no GPIO with the
4014 * specified index was assigned to the requested function it will return NULL.
4015 * This is convenient for drivers that need to handle optional GPIOs.
4017 struct gpio_desc *__must_check gpiod_get_index_optional(struct device *dev,
4020 enum gpiod_flags flags)
4022 struct gpio_desc *desc;
4024 desc = gpiod_get_index(dev, con_id, index, flags);
4026 if (PTR_ERR(desc) == -ENOENT)
4032 EXPORT_SYMBOL_GPL(gpiod_get_index_optional);
4035 * gpiod_hog - Hog the specified GPIO desc given the provided flags
4036 * @desc: gpio whose value will be assigned
4037 * @name: gpio line name
4038 * @lflags: bitmask of gpio_lookup_flags GPIO_* values - returned from
4039 * of_find_gpio() or of_get_gpio_hog()
4040 * @dflags: gpiod_flags - optional GPIO initialization flags
4042 int gpiod_hog(struct gpio_desc *desc, const char *name,
4043 unsigned long lflags, enum gpiod_flags dflags)
4045 struct gpio_chip *gc;
4046 struct gpio_desc *local_desc;
4050 gc = gpiod_to_chip(desc);
4051 hwnum = gpio_chip_hwgpio(desc);
4053 local_desc = gpiochip_request_own_desc(gc, hwnum, name,
4055 if (IS_ERR(local_desc)) {
4056 ret = PTR_ERR(local_desc);
4057 pr_err("requesting hog GPIO %s (chip %s, offset %d) failed, %d\n",
4058 name, gc->label, hwnum, ret);
4062 /* Mark GPIO as hogged so it can be identified and removed later */
4063 set_bit(FLAG_IS_HOGGED, &desc->flags);
4065 gpiod_info(desc, "hogged as %s%s\n",
4066 (dflags & GPIOD_FLAGS_BIT_DIR_OUT) ? "output" : "input",
4067 (dflags & GPIOD_FLAGS_BIT_DIR_OUT) ?
4068 (dflags & GPIOD_FLAGS_BIT_DIR_VAL) ? "/high" : "/low" : "");
4074 * gpiochip_free_hogs - Scan gpio-controller chip and release GPIO hog
4075 * @gc: gpio chip to act on
4077 static void gpiochip_free_hogs(struct gpio_chip *gc)
4081 for (id = 0; id < gc->ngpio; id++) {
4082 if (test_bit(FLAG_IS_HOGGED, &gc->gpiodev->descs[id].flags))
4083 gpiochip_free_own_desc(&gc->gpiodev->descs[id]);
4088 * gpiod_get_array - obtain multiple GPIOs from a multi-index GPIO function
4089 * @dev: GPIO consumer, can be NULL for system-global GPIOs
4090 * @con_id: function within the GPIO consumer
4091 * @flags: optional GPIO initialization flags
4093 * This function acquires all the GPIOs defined under a given function.
4095 * Return a struct gpio_descs containing an array of descriptors, -ENOENT if
4096 * no GPIO has been assigned to the requested function, or another IS_ERR()
4097 * code if an error occurred while trying to acquire the GPIOs.
4099 struct gpio_descs *__must_check gpiod_get_array(struct device *dev,
4101 enum gpiod_flags flags)
4103 struct gpio_desc *desc;
4104 struct gpio_descs *descs;
4105 struct gpio_array *array_info = NULL;
4106 struct gpio_chip *gc;
4107 int count, bitmap_size;
4109 count = gpiod_count(dev, con_id);
4111 return ERR_PTR(count);
4113 descs = kzalloc(struct_size(descs, desc, count), GFP_KERNEL);
4115 return ERR_PTR(-ENOMEM);
4117 for (descs->ndescs = 0; descs->ndescs < count; ) {
4118 desc = gpiod_get_index(dev, con_id, descs->ndescs, flags);
4120 gpiod_put_array(descs);
4121 return ERR_CAST(desc);
4124 descs->desc[descs->ndescs] = desc;
4126 gc = gpiod_to_chip(desc);
4128 * If pin hardware number of array member 0 is also 0, select
4129 * its chip as a candidate for fast bitmap processing path.
4131 if (descs->ndescs == 0 && gpio_chip_hwgpio(desc) == 0) {
4132 struct gpio_descs *array;
4134 bitmap_size = BITS_TO_LONGS(gc->ngpio > count ?
4137 array = kzalloc(struct_size(descs, desc, count) +
4138 struct_size(array_info, invert_mask,
4139 3 * bitmap_size), GFP_KERNEL);
4141 gpiod_put_array(descs);
4142 return ERR_PTR(-ENOMEM);
4145 memcpy(array, descs,
4146 struct_size(descs, desc, descs->ndescs + 1));
4150 array_info = (void *)(descs->desc + count);
4151 array_info->get_mask = array_info->invert_mask +
4153 array_info->set_mask = array_info->get_mask +
4156 array_info->desc = descs->desc;
4157 array_info->size = count;
4158 array_info->chip = gc;
4159 bitmap_set(array_info->get_mask, descs->ndescs,
4160 count - descs->ndescs);
4161 bitmap_set(array_info->set_mask, descs->ndescs,
4162 count - descs->ndescs);
4163 descs->info = array_info;
4165 /* Unmark array members which don't belong to the 'fast' chip */
4166 if (array_info && array_info->chip != gc) {
4167 __clear_bit(descs->ndescs, array_info->get_mask);
4168 __clear_bit(descs->ndescs, array_info->set_mask);
4171 * Detect array members which belong to the 'fast' chip
4172 * but their pins are not in hardware order.
4174 else if (array_info &&
4175 gpio_chip_hwgpio(desc) != descs->ndescs) {
4177 * Don't use fast path if all array members processed so
4178 * far belong to the same chip as this one but its pin
4179 * hardware number is different from its array index.
4181 if (bitmap_full(array_info->get_mask, descs->ndescs)) {
4184 __clear_bit(descs->ndescs,
4185 array_info->get_mask);
4186 __clear_bit(descs->ndescs,
4187 array_info->set_mask);
4189 } else if (array_info) {
4190 /* Exclude open drain or open source from fast output */
4191 if (gpiochip_line_is_open_drain(gc, descs->ndescs) ||
4192 gpiochip_line_is_open_source(gc, descs->ndescs))
4193 __clear_bit(descs->ndescs,
4194 array_info->set_mask);
4195 /* Identify 'fast' pins which require invertion */
4196 if (gpiod_is_active_low(desc))
4197 __set_bit(descs->ndescs,
4198 array_info->invert_mask);
4205 "GPIO array info: chip=%s, size=%d, get_mask=%lx, set_mask=%lx, invert_mask=%lx\n",
4206 array_info->chip->label, array_info->size,
4207 *array_info->get_mask, *array_info->set_mask,
4208 *array_info->invert_mask);
4211 EXPORT_SYMBOL_GPL(gpiod_get_array);
4214 * gpiod_get_array_optional - obtain multiple GPIOs from a multi-index GPIO
4216 * @dev: GPIO consumer, can be NULL for system-global GPIOs
4217 * @con_id: function within the GPIO consumer
4218 * @flags: optional GPIO initialization flags
4220 * This is equivalent to gpiod_get_array(), except that when no GPIO was
4221 * assigned to the requested function it will return NULL.
4223 struct gpio_descs *__must_check gpiod_get_array_optional(struct device *dev,
4225 enum gpiod_flags flags)
4227 struct gpio_descs *descs;
4229 descs = gpiod_get_array(dev, con_id, flags);
4230 if (PTR_ERR(descs) == -ENOENT)
4235 EXPORT_SYMBOL_GPL(gpiod_get_array_optional);
4238 * gpiod_put - dispose of a GPIO descriptor
4239 * @desc: GPIO descriptor to dispose of
4241 * No descriptor can be used after gpiod_put() has been called on it.
4243 void gpiod_put(struct gpio_desc *desc)
4248 EXPORT_SYMBOL_GPL(gpiod_put);
4251 * gpiod_put_array - dispose of multiple GPIO descriptors
4252 * @descs: struct gpio_descs containing an array of descriptors
4254 void gpiod_put_array(struct gpio_descs *descs)
4258 for (i = 0; i < descs->ndescs; i++)
4259 gpiod_put(descs->desc[i]);
4263 EXPORT_SYMBOL_GPL(gpiod_put_array);
4265 static int __init gpiolib_dev_init(void)
4269 /* Register GPIO sysfs bus */
4270 ret = bus_register(&gpio_bus_type);
4272 pr_err("gpiolib: could not register GPIO bus type\n");
4276 ret = alloc_chrdev_region(&gpio_devt, 0, GPIO_DEV_MAX, GPIOCHIP_NAME);
4278 pr_err("gpiolib: failed to allocate char dev region\n");
4279 bus_unregister(&gpio_bus_type);
4283 gpiolib_initialized = true;
4284 gpiochip_setup_devs();
4286 #if IS_ENABLED(CONFIG_OF_DYNAMIC) && IS_ENABLED(CONFIG_OF_GPIO)
4287 WARN_ON(of_reconfig_notifier_register(&gpio_of_notifier));
4288 #endif /* CONFIG_OF_DYNAMIC && CONFIG_OF_GPIO */
4292 core_initcall(gpiolib_dev_init);
4294 #ifdef CONFIG_DEBUG_FS
4296 static void gpiolib_dbg_show(struct seq_file *s, struct gpio_device *gdev)
4299 struct gpio_chip *gc = gdev->chip;
4300 unsigned gpio = gdev->base;
4301 struct gpio_desc *gdesc = &gdev->descs[0];
4306 for (i = 0; i < gdev->ngpio; i++, gpio++, gdesc++) {
4307 if (!test_bit(FLAG_REQUESTED, &gdesc->flags)) {
4309 seq_printf(s, " gpio-%-3d (%-20.20s)\n",
4315 gpiod_get_direction(gdesc);
4316 is_out = test_bit(FLAG_IS_OUT, &gdesc->flags);
4317 is_irq = test_bit(FLAG_USED_AS_IRQ, &gdesc->flags);
4318 active_low = test_bit(FLAG_ACTIVE_LOW, &gdesc->flags);
4319 seq_printf(s, " gpio-%-3d (%-20.20s|%-20.20s) %s %s %s%s",
4320 gpio, gdesc->name ? gdesc->name : "", gdesc->label,
4321 is_out ? "out" : "in ",
4322 gc->get ? (gc->get(gc, i) ? "hi" : "lo") : "? ",
4323 is_irq ? "IRQ " : "",
4324 active_low ? "ACTIVE LOW" : "");
4325 seq_printf(s, "\n");
4329 static void *gpiolib_seq_start(struct seq_file *s, loff_t *pos)
4331 unsigned long flags;
4332 struct gpio_device *gdev = NULL;
4333 loff_t index = *pos;
4337 spin_lock_irqsave(&gpio_lock, flags);
4338 list_for_each_entry(gdev, &gpio_devices, list)
4340 spin_unlock_irqrestore(&gpio_lock, flags);
4343 spin_unlock_irqrestore(&gpio_lock, flags);
4348 static void *gpiolib_seq_next(struct seq_file *s, void *v, loff_t *pos)
4350 unsigned long flags;
4351 struct gpio_device *gdev = v;
4354 spin_lock_irqsave(&gpio_lock, flags);
4355 if (list_is_last(&gdev->list, &gpio_devices))
4358 ret = list_entry(gdev->list.next, struct gpio_device, list);
4359 spin_unlock_irqrestore(&gpio_lock, flags);
4367 static void gpiolib_seq_stop(struct seq_file *s, void *v)
4371 static int gpiolib_seq_show(struct seq_file *s, void *v)
4373 struct gpio_device *gdev = v;
4374 struct gpio_chip *gc = gdev->chip;
4375 struct device *parent;
4378 seq_printf(s, "%s%s: (dangling chip)", (char *)s->private,
4379 dev_name(&gdev->dev));
4383 seq_printf(s, "%s%s: GPIOs %d-%d", (char *)s->private,
4384 dev_name(&gdev->dev),
4385 gdev->base, gdev->base + gdev->ngpio - 1);
4386 parent = gc->parent;
4388 seq_printf(s, ", parent: %s/%s",
4389 parent->bus ? parent->bus->name : "no-bus",
4392 seq_printf(s, ", %s", gc->label);
4394 seq_printf(s, ", can sleep");
4395 seq_printf(s, ":\n");
4398 gc->dbg_show(s, gc);
4400 gpiolib_dbg_show(s, gdev);
4405 static const struct seq_operations gpiolib_seq_ops = {
4406 .start = gpiolib_seq_start,
4407 .next = gpiolib_seq_next,
4408 .stop = gpiolib_seq_stop,
4409 .show = gpiolib_seq_show,
4412 static int gpiolib_open(struct inode *inode, struct file *file)
4414 return seq_open(file, &gpiolib_seq_ops);
4417 static const struct file_operations gpiolib_operations = {
4418 .owner = THIS_MODULE,
4419 .open = gpiolib_open,
4421 .llseek = seq_lseek,
4422 .release = seq_release,
4425 static int __init gpiolib_debugfs_init(void)
4427 /* /sys/kernel/debug/gpio */
4428 debugfs_create_file("gpio", S_IFREG | S_IRUGO, NULL, NULL,
4429 &gpiolib_operations);
4432 subsys_initcall(gpiolib_debugfs_init);
4434 #endif /* DEBUG_FS */