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;
343 /* First check all names if they are unique */
344 for (i = 0; i != gc->ngpio; ++i) {
345 struct gpio_desc *gpio;
347 gpio = gpio_name_to_desc(gc->names[i]);
350 "Detected name collision for GPIO name '%s'\n",
354 /* Then add all names to the GPIO descriptors */
355 for (i = 0; i != gc->ngpio; ++i)
356 gdev->descs[i].name = gc->names[i];
362 * devprop_gpiochip_set_names - Set GPIO line names using device properties
363 * @chip: GPIO chip whose lines should be named, if possible
365 * Looks for device property "gpio-line-names" and if it exists assigns
366 * GPIO line names for the chip. The memory allocated for the assigned
367 * names belong to the underlying firmware node and should not be released
370 static int devprop_gpiochip_set_names(struct gpio_chip *chip)
372 struct gpio_device *gdev = chip->gpiodev;
373 struct fwnode_handle *fwnode = dev_fwnode(&gdev->dev);
378 count = fwnode_property_string_array_count(fwnode, "gpio-line-names");
382 if (count > gdev->ngpio) {
383 dev_warn(&gdev->dev, "gpio-line-names is length %d but should be at most length %d",
388 names = kcalloc(count, sizeof(*names), GFP_KERNEL);
392 ret = fwnode_property_read_string_array(fwnode, "gpio-line-names",
395 dev_warn(&gdev->dev, "failed to read GPIO line names\n");
400 for (i = 0; i < count; i++)
401 gdev->descs[i].name = names[i];
408 static unsigned long *gpiochip_allocate_mask(struct gpio_chip *gc)
412 p = bitmap_alloc(gc->ngpio, GFP_KERNEL);
416 /* Assume by default all GPIOs are valid */
417 bitmap_fill(p, gc->ngpio);
422 static int gpiochip_alloc_valid_mask(struct gpio_chip *gc)
424 if (!(of_gpio_need_valid_mask(gc) || gc->init_valid_mask))
427 gc->valid_mask = gpiochip_allocate_mask(gc);
434 static int gpiochip_init_valid_mask(struct gpio_chip *gc)
436 if (gc->init_valid_mask)
437 return gc->init_valid_mask(gc,
444 static void gpiochip_free_valid_mask(struct gpio_chip *gc)
446 bitmap_free(gc->valid_mask);
447 gc->valid_mask = NULL;
450 static int gpiochip_add_pin_ranges(struct gpio_chip *gc)
452 if (gc->add_pin_ranges)
453 return gc->add_pin_ranges(gc);
458 bool gpiochip_line_is_valid(const struct gpio_chip *gc,
461 /* No mask means all valid */
462 if (likely(!gc->valid_mask))
464 return test_bit(offset, gc->valid_mask);
466 EXPORT_SYMBOL_GPL(gpiochip_line_is_valid);
468 static void gpiodevice_release(struct device *dev)
470 struct gpio_device *gdev = dev_get_drvdata(dev);
473 spin_lock_irqsave(&gpio_lock, flags);
474 list_del(&gdev->list);
475 spin_unlock_irqrestore(&gpio_lock, flags);
477 ida_free(&gpio_ida, gdev->id);
478 kfree_const(gdev->label);
483 #ifdef CONFIG_GPIO_CDEV
484 #define gcdev_register(gdev, devt) gpiolib_cdev_register((gdev), (devt))
485 #define gcdev_unregister(gdev) gpiolib_cdev_unregister((gdev))
488 * gpiolib_cdev_register() indirectly calls device_add(), which is still
489 * required even when cdev is not selected.
491 #define gcdev_register(gdev, devt) device_add(&(gdev)->dev)
492 #define gcdev_unregister(gdev) device_del(&(gdev)->dev)
495 static int gpiochip_setup_dev(struct gpio_device *gdev)
499 ret = gcdev_register(gdev, gpio_devt);
503 ret = gpiochip_sysfs_register(gdev);
505 goto err_remove_device;
507 /* From this point, the .release() function cleans up gpio_device */
508 gdev->dev.release = gpiodevice_release;
509 dev_dbg(&gdev->dev, "registered GPIOs %d to %d on %s\n", gdev->base,
510 gdev->base + gdev->ngpio - 1, gdev->chip->label ? : "generic");
515 gcdev_unregister(gdev);
519 static void gpiochip_machine_hog(struct gpio_chip *gc, struct gpiod_hog *hog)
521 struct gpio_desc *desc;
524 desc = gpiochip_get_desc(gc, hog->chip_hwnum);
526 chip_err(gc, "%s: unable to get GPIO desc: %ld\n", __func__,
531 if (test_bit(FLAG_IS_HOGGED, &desc->flags))
534 rv = gpiod_hog(desc, hog->line_name, hog->lflags, hog->dflags);
536 gpiod_err(desc, "%s: unable to hog GPIO line (%s:%u): %d\n",
537 __func__, gc->label, hog->chip_hwnum, rv);
540 static void machine_gpiochip_add(struct gpio_chip *gc)
542 struct gpiod_hog *hog;
544 mutex_lock(&gpio_machine_hogs_mutex);
546 list_for_each_entry(hog, &gpio_machine_hogs, list) {
547 if (!strcmp(gc->label, hog->chip_label))
548 gpiochip_machine_hog(gc, hog);
551 mutex_unlock(&gpio_machine_hogs_mutex);
554 static void gpiochip_setup_devs(void)
556 struct gpio_device *gdev;
559 list_for_each_entry(gdev, &gpio_devices, list) {
560 ret = gpiochip_setup_dev(gdev);
563 "Failed to initialize gpio device (%d)\n", ret);
567 int gpiochip_add_data_with_key(struct gpio_chip *gc, void *data,
568 struct lock_class_key *lock_key,
569 struct lock_class_key *request_key)
571 struct fwnode_handle *fwnode = gc->parent ? dev_fwnode(gc->parent) : NULL;
576 struct gpio_device *gdev;
579 * First: allocate and populate the internal stat container, and
580 * set up the struct device.
582 gdev = kzalloc(sizeof(*gdev), GFP_KERNEL);
585 gdev->dev.bus = &gpio_bus_type;
589 gdev->dev.parent = gc->parent;
590 gdev->dev.of_node = gc->parent->of_node;
593 #ifdef CONFIG_OF_GPIO
594 /* If the gpiochip has an assigned OF node this takes precedence */
596 gdev->dev.of_node = gc->of_node;
598 gc->of_node = gdev->dev.of_node;
602 * Assign fwnode depending on the result of the previous calls,
603 * if none of them succeed, assign it to the parent's one.
605 gdev->dev.fwnode = dev_fwnode(&gdev->dev) ?: fwnode;
607 gdev->id = ida_alloc(&gpio_ida, GFP_KERNEL);
613 ret = dev_set_name(&gdev->dev, GPIOCHIP_NAME "%d", gdev->id);
617 device_initialize(&gdev->dev);
618 dev_set_drvdata(&gdev->dev, gdev);
619 if (gc->parent && gc->parent->driver)
620 gdev->owner = gc->parent->driver->owner;
622 /* TODO: remove chip->owner */
623 gdev->owner = gc->owner;
625 gdev->owner = THIS_MODULE;
627 gdev->descs = kcalloc(gc->ngpio, sizeof(gdev->descs[0]), GFP_KERNEL);
630 goto err_free_dev_name;
633 if (gc->ngpio == 0) {
634 chip_err(gc, "tried to insert a GPIO chip with zero lines\n");
639 if (gc->ngpio > FASTPATH_NGPIO)
640 chip_warn(gc, "line cnt %u is greater than fast path cnt %u\n",
641 gc->ngpio, FASTPATH_NGPIO);
643 gdev->label = kstrdup_const(gc->label ?: "unknown", GFP_KERNEL);
649 gdev->ngpio = gc->ngpio;
652 spin_lock_irqsave(&gpio_lock, flags);
655 * TODO: this allocates a Linux GPIO number base in the global
656 * GPIO numberspace for this chip. In the long run we want to
657 * get *rid* of this numberspace and use only descriptors, but
658 * it may be a pipe dream. It will not happen before we get rid
659 * of the sysfs interface anyways.
662 base = gpiochip_find_base(gc->ngpio);
665 spin_unlock_irqrestore(&gpio_lock, flags);
669 * TODO: it should not be necessary to reflect the assigned
670 * base outside of the GPIO subsystem. Go over drivers and
671 * see if anyone makes use of this, else drop this and assign
678 ret = gpiodev_add_to_list(gdev);
680 spin_unlock_irqrestore(&gpio_lock, flags);
684 for (i = 0; i < gc->ngpio; i++)
685 gdev->descs[i].gdev = gdev;
687 spin_unlock_irqrestore(&gpio_lock, flags);
689 BLOCKING_INIT_NOTIFIER_HEAD(&gdev->notifier);
691 #ifdef CONFIG_PINCTRL
692 INIT_LIST_HEAD(&gdev->pin_ranges);
696 ret = gpiochip_set_desc_names(gc);
698 ret = devprop_gpiochip_set_names(gc);
700 goto err_remove_from_list;
702 ret = gpiochip_alloc_valid_mask(gc);
704 goto err_remove_from_list;
706 ret = of_gpiochip_add(gc);
708 goto err_free_gpiochip_mask;
710 ret = gpiochip_init_valid_mask(gc);
712 goto err_remove_of_chip;
714 for (i = 0; i < gc->ngpio; i++) {
715 struct gpio_desc *desc = &gdev->descs[i];
717 if (gc->get_direction && gpiochip_line_is_valid(gc, i)) {
718 assign_bit(FLAG_IS_OUT,
719 &desc->flags, !gc->get_direction(gc, i));
721 assign_bit(FLAG_IS_OUT,
722 &desc->flags, !gc->direction_input);
726 ret = gpiochip_add_pin_ranges(gc);
728 goto err_remove_of_chip;
730 acpi_gpiochip_add(gc);
732 machine_gpiochip_add(gc);
734 ret = gpiochip_irqchip_init_valid_mask(gc);
736 goto err_remove_acpi_chip;
738 ret = gpiochip_irqchip_init_hw(gc);
740 goto err_remove_acpi_chip;
742 ret = gpiochip_add_irqchip(gc, lock_key, request_key);
744 goto err_remove_irqchip_mask;
747 * By first adding the chardev, and then adding the device,
748 * we get a device node entry in sysfs under
749 * /sys/bus/gpio/devices/gpiochipN/dev that can be used for
750 * coldplug of device nodes and other udev business.
751 * We can do this only if gpiolib has been initialized.
752 * Otherwise, defer until later.
754 if (gpiolib_initialized) {
755 ret = gpiochip_setup_dev(gdev);
757 goto err_remove_irqchip;
762 gpiochip_irqchip_remove(gc);
763 err_remove_irqchip_mask:
764 gpiochip_irqchip_free_valid_mask(gc);
765 err_remove_acpi_chip:
766 acpi_gpiochip_remove(gc);
768 gpiochip_free_hogs(gc);
769 of_gpiochip_remove(gc);
770 err_free_gpiochip_mask:
771 gpiochip_remove_pin_ranges(gc);
772 gpiochip_free_valid_mask(gc);
773 err_remove_from_list:
774 spin_lock_irqsave(&gpio_lock, flags);
775 list_del(&gdev->list);
776 spin_unlock_irqrestore(&gpio_lock, flags);
778 kfree_const(gdev->label);
782 kfree(dev_name(&gdev->dev));
784 ida_free(&gpio_ida, gdev->id);
786 /* failures here can mean systems won't boot... */
787 pr_err("%s: GPIOs %d..%d (%s) failed to register, %d\n", __func__,
788 gdev->base, gdev->base + gdev->ngpio - 1,
789 gc->label ? : "generic", ret);
793 EXPORT_SYMBOL_GPL(gpiochip_add_data_with_key);
796 * gpiochip_get_data() - get per-subdriver data for the chip
800 * The per-subdriver data for the chip.
802 void *gpiochip_get_data(struct gpio_chip *gc)
804 return gc->gpiodev->data;
806 EXPORT_SYMBOL_GPL(gpiochip_get_data);
809 * gpiochip_remove() - unregister a gpio_chip
810 * @gc: the chip to unregister
812 * A gpio_chip with any GPIOs still requested may not be removed.
814 void gpiochip_remove(struct gpio_chip *gc)
816 struct gpio_device *gdev = gc->gpiodev;
820 /* FIXME: should the legacy sysfs handling be moved to gpio_device? */
821 gpiochip_sysfs_unregister(gdev);
822 gpiochip_free_hogs(gc);
823 /* Numb the device, cancelling all outstanding operations */
825 gpiochip_irqchip_remove(gc);
826 acpi_gpiochip_remove(gc);
827 of_gpiochip_remove(gc);
828 gpiochip_remove_pin_ranges(gc);
829 gpiochip_free_valid_mask(gc);
831 * We accept no more calls into the driver from this point, so
832 * NULL the driver data pointer
836 spin_lock_irqsave(&gpio_lock, flags);
837 for (i = 0; i < gdev->ngpio; i++) {
838 if (gpiochip_is_requested(gc, i))
841 spin_unlock_irqrestore(&gpio_lock, flags);
843 if (i != gdev->ngpio)
845 "REMOVING GPIOCHIP WITH GPIOS STILL REQUESTED\n");
848 * The gpiochip side puts its use of the device to rest here:
849 * if there are no userspace clients, the chardev and device will
850 * be removed, else it will be dangling until the last user is
853 gcdev_unregister(gdev);
854 put_device(&gdev->dev);
856 EXPORT_SYMBOL_GPL(gpiochip_remove);
859 * gpiochip_find() - iterator for locating a specific gpio_chip
860 * @data: data to pass to match function
861 * @match: Callback function to check gpio_chip
863 * Similar to bus_find_device. It returns a reference to a gpio_chip as
864 * determined by a user supplied @match callback. The callback should return
865 * 0 if the device doesn't match and non-zero if it does. If the callback is
866 * non-zero, this function will return to the caller and not iterate over any
869 struct gpio_chip *gpiochip_find(void *data,
870 int (*match)(struct gpio_chip *gc,
873 struct gpio_device *gdev;
874 struct gpio_chip *gc = NULL;
877 spin_lock_irqsave(&gpio_lock, flags);
878 list_for_each_entry(gdev, &gpio_devices, list)
879 if (gdev->chip && match(gdev->chip, data)) {
884 spin_unlock_irqrestore(&gpio_lock, flags);
888 EXPORT_SYMBOL_GPL(gpiochip_find);
890 static int gpiochip_match_name(struct gpio_chip *gc, void *data)
892 const char *name = data;
894 return !strcmp(gc->label, name);
897 static struct gpio_chip *find_chip_by_name(const char *name)
899 return gpiochip_find((void *)name, gpiochip_match_name);
902 #ifdef CONFIG_GPIOLIB_IRQCHIP
905 * The following is irqchip helper code for gpiochips.
908 static int gpiochip_irqchip_init_hw(struct gpio_chip *gc)
910 struct gpio_irq_chip *girq = &gc->irq;
915 return girq->init_hw(gc);
918 static int gpiochip_irqchip_init_valid_mask(struct gpio_chip *gc)
920 struct gpio_irq_chip *girq = &gc->irq;
922 if (!girq->init_valid_mask)
925 girq->valid_mask = gpiochip_allocate_mask(gc);
926 if (!girq->valid_mask)
929 girq->init_valid_mask(gc, girq->valid_mask, gc->ngpio);
934 static void gpiochip_irqchip_free_valid_mask(struct gpio_chip *gc)
936 bitmap_free(gc->irq.valid_mask);
937 gc->irq.valid_mask = NULL;
940 bool gpiochip_irqchip_irq_valid(const struct gpio_chip *gc,
943 if (!gpiochip_line_is_valid(gc, offset))
945 /* No mask means all valid */
946 if (likely(!gc->irq.valid_mask))
948 return test_bit(offset, gc->irq.valid_mask);
950 EXPORT_SYMBOL_GPL(gpiochip_irqchip_irq_valid);
953 * gpiochip_set_cascaded_irqchip() - connects a cascaded irqchip to a gpiochip
954 * @gc: the gpiochip to set the irqchip chain to
955 * @parent_irq: the irq number corresponding to the parent IRQ for this
957 * @parent_handler: the parent interrupt handler for the accumulated IRQ
958 * coming out of the gpiochip. If the interrupt is nested rather than
959 * cascaded, pass NULL in this handler argument
961 static void gpiochip_set_cascaded_irqchip(struct gpio_chip *gc,
962 unsigned int parent_irq,
963 irq_flow_handler_t parent_handler)
965 struct gpio_irq_chip *girq = &gc->irq;
966 struct device *dev = &gc->gpiodev->dev;
969 chip_err(gc, "called %s before setting up irqchip\n",
974 if (parent_handler) {
977 "you cannot have chained interrupts on a chip that may sleep\n");
980 girq->parents = devm_kcalloc(dev, 1,
981 sizeof(*girq->parents),
983 if (!girq->parents) {
984 chip_err(gc, "out of memory allocating parent IRQ\n");
987 girq->parents[0] = parent_irq;
988 girq->num_parents = 1;
990 * The parent irqchip is already using the chip_data for this
991 * irqchip, so our callbacks simply use the handler_data.
993 irq_set_chained_handler_and_data(parent_irq, parent_handler,
999 * gpiochip_set_nested_irqchip() - connects a nested irqchip to a gpiochip
1000 * @gc: the gpiochip to set the irqchip nested handler to
1001 * @irqchip: the irqchip to nest to the gpiochip
1002 * @parent_irq: the irq number corresponding to the parent IRQ for this
1005 void gpiochip_set_nested_irqchip(struct gpio_chip *gc,
1006 struct irq_chip *irqchip,
1007 unsigned int parent_irq)
1009 gpiochip_set_cascaded_irqchip(gc, parent_irq, NULL);
1011 EXPORT_SYMBOL_GPL(gpiochip_set_nested_irqchip);
1013 #ifdef CONFIG_IRQ_DOMAIN_HIERARCHY
1016 * gpiochip_set_hierarchical_irqchip() - connects a hierarchical irqchip
1018 * @gc: the gpiochip to set the irqchip hierarchical handler to
1019 * @irqchip: the irqchip to handle this level of the hierarchy, the interrupt
1020 * will then percolate up to the parent
1022 static void gpiochip_set_hierarchical_irqchip(struct gpio_chip *gc,
1023 struct irq_chip *irqchip)
1025 /* DT will deal with mapping each IRQ as we go along */
1026 if (is_of_node(gc->irq.fwnode))
1030 * This is for legacy and boardfile "irqchip" fwnodes: allocate
1031 * irqs upfront instead of dynamically since we don't have the
1032 * dynamic type of allocation that hardware description languages
1033 * provide. Once all GPIO drivers using board files are gone from
1034 * the kernel we can delete this code, but for a transitional period
1035 * it is necessary to keep this around.
1037 if (is_fwnode_irqchip(gc->irq.fwnode)) {
1041 for (i = 0; i < gc->ngpio; i++) {
1042 struct irq_fwspec fwspec;
1043 unsigned int parent_hwirq;
1044 unsigned int parent_type;
1045 struct gpio_irq_chip *girq = &gc->irq;
1048 * We call the child to parent translation function
1049 * only to check if the child IRQ is valid or not.
1050 * Just pick the rising edge type here as that is what
1051 * we likely need to support.
1053 ret = girq->child_to_parent_hwirq(gc, i,
1054 IRQ_TYPE_EDGE_RISING,
1058 chip_err(gc, "skip set-up on hwirq %d\n",
1063 fwspec.fwnode = gc->irq.fwnode;
1064 /* This is the hwirq for the GPIO line side of things */
1065 fwspec.param[0] = girq->child_offset_to_irq(gc, i);
1066 /* Just pick something */
1067 fwspec.param[1] = IRQ_TYPE_EDGE_RISING;
1068 fwspec.param_count = 2;
1069 ret = __irq_domain_alloc_irqs(gc->irq.domain,
1070 /* just pick something */
1079 "can not allocate irq for GPIO line %d parent hwirq %d in hierarchy domain: %d\n",
1086 chip_err(gc, "%s unknown fwnode type proceed anyway\n", __func__);
1091 static int gpiochip_hierarchy_irq_domain_translate(struct irq_domain *d,
1092 struct irq_fwspec *fwspec,
1093 unsigned long *hwirq,
1096 /* We support standard DT translation */
1097 if (is_of_node(fwspec->fwnode) && fwspec->param_count == 2) {
1098 return irq_domain_translate_twocell(d, fwspec, hwirq, type);
1101 /* This is for board files and others not using DT */
1102 if (is_fwnode_irqchip(fwspec->fwnode)) {
1105 ret = irq_domain_translate_twocell(d, fwspec, hwirq, type);
1108 WARN_ON(*type == IRQ_TYPE_NONE);
1114 static int gpiochip_hierarchy_irq_domain_alloc(struct irq_domain *d,
1116 unsigned int nr_irqs,
1119 struct gpio_chip *gc = d->host_data;
1120 irq_hw_number_t hwirq;
1121 unsigned int type = IRQ_TYPE_NONE;
1122 struct irq_fwspec *fwspec = data;
1124 unsigned int parent_hwirq;
1125 unsigned int parent_type;
1126 struct gpio_irq_chip *girq = &gc->irq;
1130 * The nr_irqs parameter is always one except for PCI multi-MSI
1131 * so this should not happen.
1133 WARN_ON(nr_irqs != 1);
1135 ret = gc->irq.child_irq_domain_ops.translate(d, fwspec, &hwirq, &type);
1139 chip_dbg(gc, "allocate IRQ %d, hwirq %lu\n", irq, hwirq);
1141 ret = girq->child_to_parent_hwirq(gc, hwirq, type,
1142 &parent_hwirq, &parent_type);
1144 chip_err(gc, "can't look up hwirq %lu\n", hwirq);
1147 chip_dbg(gc, "found parent hwirq %u\n", parent_hwirq);
1150 * We set handle_bad_irq because the .set_type() should
1151 * always be invoked and set the right type of handler.
1153 irq_domain_set_info(d,
1162 /* This parent only handles asserted level IRQs */
1163 parent_arg = girq->populate_parent_alloc_arg(gc, parent_hwirq, parent_type);
1167 chip_dbg(gc, "alloc_irqs_parent for %d parent hwirq %d\n",
1169 irq_set_lockdep_class(irq, gc->irq.lock_key, gc->irq.request_key);
1170 ret = irq_domain_alloc_irqs_parent(d, irq, 1, parent_arg);
1172 * If the parent irqdomain is msi, the interrupts have already
1173 * been allocated, so the EEXIST is good.
1175 if (irq_domain_is_msi(d->parent) && (ret == -EEXIST))
1179 "failed to allocate parent hwirq %d for hwirq %lu\n",
1180 parent_hwirq, hwirq);
1186 static unsigned int gpiochip_child_offset_to_irq_noop(struct gpio_chip *gc,
1187 unsigned int offset)
1192 static void gpiochip_hierarchy_setup_domain_ops(struct irq_domain_ops *ops)
1194 ops->activate = gpiochip_irq_domain_activate;
1195 ops->deactivate = gpiochip_irq_domain_deactivate;
1196 ops->alloc = gpiochip_hierarchy_irq_domain_alloc;
1197 ops->free = irq_domain_free_irqs_common;
1200 * We only allow overriding the translate() function for
1201 * hierarchical chips, and this should only be done if the user
1202 * really need something other than 1:1 translation.
1204 if (!ops->translate)
1205 ops->translate = gpiochip_hierarchy_irq_domain_translate;
1208 static int gpiochip_hierarchy_add_domain(struct gpio_chip *gc)
1210 if (!gc->irq.child_to_parent_hwirq ||
1212 chip_err(gc, "missing irqdomain vital data\n");
1216 if (!gc->irq.child_offset_to_irq)
1217 gc->irq.child_offset_to_irq = gpiochip_child_offset_to_irq_noop;
1219 if (!gc->irq.populate_parent_alloc_arg)
1220 gc->irq.populate_parent_alloc_arg =
1221 gpiochip_populate_parent_fwspec_twocell;
1223 gpiochip_hierarchy_setup_domain_ops(&gc->irq.child_irq_domain_ops);
1225 gc->irq.domain = irq_domain_create_hierarchy(
1226 gc->irq.parent_domain,
1230 &gc->irq.child_irq_domain_ops,
1233 if (!gc->irq.domain)
1236 gpiochip_set_hierarchical_irqchip(gc, gc->irq.chip);
1241 static bool gpiochip_hierarchy_is_hierarchical(struct gpio_chip *gc)
1243 return !!gc->irq.parent_domain;
1246 void *gpiochip_populate_parent_fwspec_twocell(struct gpio_chip *gc,
1247 unsigned int parent_hwirq,
1248 unsigned int parent_type)
1250 struct irq_fwspec *fwspec;
1252 fwspec = kmalloc(sizeof(*fwspec), GFP_KERNEL);
1256 fwspec->fwnode = gc->irq.parent_domain->fwnode;
1257 fwspec->param_count = 2;
1258 fwspec->param[0] = parent_hwirq;
1259 fwspec->param[1] = parent_type;
1263 EXPORT_SYMBOL_GPL(gpiochip_populate_parent_fwspec_twocell);
1265 void *gpiochip_populate_parent_fwspec_fourcell(struct gpio_chip *gc,
1266 unsigned int parent_hwirq,
1267 unsigned int parent_type)
1269 struct irq_fwspec *fwspec;
1271 fwspec = kmalloc(sizeof(*fwspec), GFP_KERNEL);
1275 fwspec->fwnode = gc->irq.parent_domain->fwnode;
1276 fwspec->param_count = 4;
1277 fwspec->param[0] = 0;
1278 fwspec->param[1] = parent_hwirq;
1279 fwspec->param[2] = 0;
1280 fwspec->param[3] = parent_type;
1284 EXPORT_SYMBOL_GPL(gpiochip_populate_parent_fwspec_fourcell);
1288 static int gpiochip_hierarchy_add_domain(struct gpio_chip *gc)
1293 static bool gpiochip_hierarchy_is_hierarchical(struct gpio_chip *gc)
1298 #endif /* CONFIG_IRQ_DOMAIN_HIERARCHY */
1301 * gpiochip_irq_map() - maps an IRQ into a GPIO irqchip
1302 * @d: the irqdomain used by this irqchip
1303 * @irq: the global irq number used by this GPIO irqchip irq
1304 * @hwirq: the local IRQ/GPIO line offset on this gpiochip
1306 * This function will set up the mapping for a certain IRQ line on a
1307 * gpiochip by assigning the gpiochip as chip data, and using the irqchip
1308 * stored inside the gpiochip.
1310 int gpiochip_irq_map(struct irq_domain *d, unsigned int irq,
1311 irq_hw_number_t hwirq)
1313 struct gpio_chip *gc = d->host_data;
1316 if (!gpiochip_irqchip_irq_valid(gc, hwirq))
1319 irq_set_chip_data(irq, gc);
1321 * This lock class tells lockdep that GPIO irqs are in a different
1322 * category than their parents, so it won't report false recursion.
1324 irq_set_lockdep_class(irq, gc->irq.lock_key, gc->irq.request_key);
1325 irq_set_chip_and_handler(irq, gc->irq.chip, gc->irq.handler);
1326 /* Chips that use nested thread handlers have them marked */
1327 if (gc->irq.threaded)
1328 irq_set_nested_thread(irq, 1);
1329 irq_set_noprobe(irq);
1331 if (gc->irq.num_parents == 1)
1332 ret = irq_set_parent(irq, gc->irq.parents[0]);
1333 else if (gc->irq.map)
1334 ret = irq_set_parent(irq, gc->irq.map[hwirq]);
1340 * No set-up of the hardware will happen if IRQ_TYPE_NONE
1341 * is passed as default type.
1343 if (gc->irq.default_type != IRQ_TYPE_NONE)
1344 irq_set_irq_type(irq, gc->irq.default_type);
1348 EXPORT_SYMBOL_GPL(gpiochip_irq_map);
1350 void gpiochip_irq_unmap(struct irq_domain *d, unsigned int irq)
1352 struct gpio_chip *gc = d->host_data;
1354 if (gc->irq.threaded)
1355 irq_set_nested_thread(irq, 0);
1356 irq_set_chip_and_handler(irq, NULL, NULL);
1357 irq_set_chip_data(irq, NULL);
1359 EXPORT_SYMBOL_GPL(gpiochip_irq_unmap);
1361 static const struct irq_domain_ops gpiochip_domain_ops = {
1362 .map = gpiochip_irq_map,
1363 .unmap = gpiochip_irq_unmap,
1364 /* Virtually all GPIO irqchips are twocell:ed */
1365 .xlate = irq_domain_xlate_twocell,
1369 * TODO: move these activate/deactivate in under the hierarchicial
1370 * irqchip implementation as static once SPMI and SSBI (all external
1371 * users) are phased over.
1374 * gpiochip_irq_domain_activate() - Lock a GPIO to be used as an IRQ
1375 * @domain: The IRQ domain used by this IRQ chip
1376 * @data: Outermost irq_data associated with the IRQ
1377 * @reserve: If set, only reserve an interrupt vector instead of assigning one
1379 * This function is a wrapper that calls gpiochip_lock_as_irq() and is to be
1380 * used as the activate function for the &struct irq_domain_ops. The host_data
1381 * for the IRQ domain must be the &struct gpio_chip.
1383 int gpiochip_irq_domain_activate(struct irq_domain *domain,
1384 struct irq_data *data, bool reserve)
1386 struct gpio_chip *gc = domain->host_data;
1388 return gpiochip_lock_as_irq(gc, data->hwirq);
1390 EXPORT_SYMBOL_GPL(gpiochip_irq_domain_activate);
1393 * gpiochip_irq_domain_deactivate() - Unlock a GPIO used as an IRQ
1394 * @domain: The IRQ domain used by this IRQ chip
1395 * @data: Outermost irq_data associated with the IRQ
1397 * This function is a wrapper that will call gpiochip_unlock_as_irq() and is to
1398 * be used as the deactivate function for the &struct irq_domain_ops. The
1399 * host_data for the IRQ domain must be the &struct gpio_chip.
1401 void gpiochip_irq_domain_deactivate(struct irq_domain *domain,
1402 struct irq_data *data)
1404 struct gpio_chip *gc = domain->host_data;
1406 return gpiochip_unlock_as_irq(gc, data->hwirq);
1408 EXPORT_SYMBOL_GPL(gpiochip_irq_domain_deactivate);
1410 static int gpiochip_to_irq(struct gpio_chip *gc, unsigned offset)
1412 struct irq_domain *domain = gc->irq.domain;
1414 #ifdef CONFIG_GPIOLIB_IRQCHIP
1416 * Avoid race condition with other code, which tries to lookup
1417 * an IRQ before the irqchip has been properly registered,
1418 * i.e. while gpiochip is still being brought up.
1420 if (!gc->irq.initialized)
1421 return -EPROBE_DEFER;
1424 if (!gpiochip_irqchip_irq_valid(gc, offset))
1427 #ifdef CONFIG_IRQ_DOMAIN_HIERARCHY
1428 if (irq_domain_is_hierarchy(domain)) {
1429 struct irq_fwspec spec;
1431 spec.fwnode = domain->fwnode;
1432 spec.param_count = 2;
1433 spec.param[0] = gc->irq.child_offset_to_irq(gc, offset);
1434 spec.param[1] = IRQ_TYPE_NONE;
1436 return irq_create_fwspec_mapping(&spec);
1440 return irq_create_mapping(domain, offset);
1443 static int gpiochip_irq_reqres(struct irq_data *d)
1445 struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
1447 return gpiochip_reqres_irq(gc, d->hwirq);
1450 static void gpiochip_irq_relres(struct irq_data *d)
1452 struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
1454 gpiochip_relres_irq(gc, d->hwirq);
1457 static void gpiochip_irq_mask(struct irq_data *d)
1459 struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
1461 if (gc->irq.irq_mask)
1462 gc->irq.irq_mask(d);
1463 gpiochip_disable_irq(gc, d->hwirq);
1466 static void gpiochip_irq_unmask(struct irq_data *d)
1468 struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
1470 gpiochip_enable_irq(gc, d->hwirq);
1471 if (gc->irq.irq_unmask)
1472 gc->irq.irq_unmask(d);
1475 static void gpiochip_irq_enable(struct irq_data *d)
1477 struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
1479 gpiochip_enable_irq(gc, d->hwirq);
1480 gc->irq.irq_enable(d);
1483 static void gpiochip_irq_disable(struct irq_data *d)
1485 struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
1487 gc->irq.irq_disable(d);
1488 gpiochip_disable_irq(gc, d->hwirq);
1491 static void gpiochip_set_irq_hooks(struct gpio_chip *gc)
1493 struct irq_chip *irqchip = gc->irq.chip;
1495 if (!irqchip->irq_request_resources &&
1496 !irqchip->irq_release_resources) {
1497 irqchip->irq_request_resources = gpiochip_irq_reqres;
1498 irqchip->irq_release_resources = gpiochip_irq_relres;
1500 if (WARN_ON(gc->irq.irq_enable))
1502 /* Check if the irqchip already has this hook... */
1503 if (irqchip->irq_enable == gpiochip_irq_enable ||
1504 irqchip->irq_mask == gpiochip_irq_mask) {
1506 * ...and if so, give a gentle warning that this is bad
1510 "detected irqchip that is shared with multiple gpiochips: please fix the driver.\n");
1514 if (irqchip->irq_disable) {
1515 gc->irq.irq_disable = irqchip->irq_disable;
1516 irqchip->irq_disable = gpiochip_irq_disable;
1518 gc->irq.irq_mask = irqchip->irq_mask;
1519 irqchip->irq_mask = gpiochip_irq_mask;
1522 if (irqchip->irq_enable) {
1523 gc->irq.irq_enable = irqchip->irq_enable;
1524 irqchip->irq_enable = gpiochip_irq_enable;
1526 gc->irq.irq_unmask = irqchip->irq_unmask;
1527 irqchip->irq_unmask = gpiochip_irq_unmask;
1532 * gpiochip_add_irqchip() - adds an IRQ chip to a GPIO chip
1533 * @gc: the GPIO chip to add the IRQ chip to
1534 * @lock_key: lockdep class for IRQ lock
1535 * @request_key: lockdep class for IRQ request
1537 static int gpiochip_add_irqchip(struct gpio_chip *gc,
1538 struct lock_class_key *lock_key,
1539 struct lock_class_key *request_key)
1541 struct irq_chip *irqchip = gc->irq.chip;
1542 const struct irq_domain_ops *ops = NULL;
1543 struct device_node *np;
1550 if (gc->irq.parent_handler && gc->can_sleep) {
1551 chip_err(gc, "you cannot have chained interrupts on a chip that may sleep\n");
1555 np = gc->gpiodev->dev.of_node;
1556 type = gc->irq.default_type;
1559 * Specifying a default trigger is a terrible idea if DT or ACPI is
1560 * used to configure the interrupts, as you may end up with
1561 * conflicting triggers. Tell the user, and reset to NONE.
1563 if (WARN(np && type != IRQ_TYPE_NONE,
1564 "%s: Ignoring %u default trigger\n", np->full_name, type))
1565 type = IRQ_TYPE_NONE;
1567 if (has_acpi_companion(gc->parent) && type != IRQ_TYPE_NONE) {
1568 acpi_handle_warn(ACPI_HANDLE(gc->parent),
1569 "Ignoring %u default trigger\n", type);
1570 type = IRQ_TYPE_NONE;
1573 gc->to_irq = gpiochip_to_irq;
1574 gc->irq.default_type = type;
1575 gc->irq.lock_key = lock_key;
1576 gc->irq.request_key = request_key;
1578 /* If a parent irqdomain is provided, let's build a hierarchy */
1579 if (gpiochip_hierarchy_is_hierarchical(gc)) {
1580 int ret = gpiochip_hierarchy_add_domain(gc);
1584 /* Some drivers provide custom irqdomain ops */
1585 if (gc->irq.domain_ops)
1586 ops = gc->irq.domain_ops;
1589 ops = &gpiochip_domain_ops;
1590 gc->irq.domain = irq_domain_add_simple(np,
1594 if (!gc->irq.domain)
1598 if (gc->irq.parent_handler) {
1599 void *data = gc->irq.parent_handler_data ?: gc;
1601 for (i = 0; i < gc->irq.num_parents; i++) {
1603 * The parent IRQ chip is already using the chip_data
1604 * for this IRQ chip, so our callbacks simply use the
1607 irq_set_chained_handler_and_data(gc->irq.parents[i],
1608 gc->irq.parent_handler,
1613 gpiochip_set_irq_hooks(gc);
1616 * Using barrier() here to prevent compiler from reordering
1617 * gc->irq.initialized before initialization of above
1618 * GPIO chip irq members.
1622 gc->irq.initialized = true;
1624 acpi_gpiochip_request_interrupts(gc);
1630 * gpiochip_irqchip_remove() - removes an irqchip added to a gpiochip
1631 * @gc: the gpiochip to remove the irqchip from
1633 * This is called only from gpiochip_remove()
1635 static void gpiochip_irqchip_remove(struct gpio_chip *gc)
1637 struct irq_chip *irqchip = gc->irq.chip;
1638 unsigned int offset;
1640 acpi_gpiochip_free_interrupts(gc);
1642 if (irqchip && gc->irq.parent_handler) {
1643 struct gpio_irq_chip *irq = &gc->irq;
1646 for (i = 0; i < irq->num_parents; i++)
1647 irq_set_chained_handler_and_data(irq->parents[i],
1651 /* Remove all IRQ mappings and delete the domain */
1652 if (gc->irq.domain) {
1655 for (offset = 0; offset < gc->ngpio; offset++) {
1656 if (!gpiochip_irqchip_irq_valid(gc, offset))
1659 irq = irq_find_mapping(gc->irq.domain, offset);
1660 irq_dispose_mapping(irq);
1663 irq_domain_remove(gc->irq.domain);
1667 if (irqchip->irq_request_resources == gpiochip_irq_reqres) {
1668 irqchip->irq_request_resources = NULL;
1669 irqchip->irq_release_resources = NULL;
1671 if (irqchip->irq_enable == gpiochip_irq_enable) {
1672 irqchip->irq_enable = gc->irq.irq_enable;
1673 irqchip->irq_disable = gc->irq.irq_disable;
1676 gc->irq.irq_enable = NULL;
1677 gc->irq.irq_disable = NULL;
1678 gc->irq.chip = NULL;
1680 gpiochip_irqchip_free_valid_mask(gc);
1684 * gpiochip_irqchip_add_key() - adds an irqchip to a gpiochip
1685 * @gc: the gpiochip to add the irqchip to
1686 * @irqchip: the irqchip to add to the gpiochip
1687 * @first_irq: if not dynamically assigned, the base (first) IRQ to
1688 * allocate gpiochip irqs from
1689 * @handler: the irq handler to use (often a predefined irq core function)
1690 * @type: the default type for IRQs on this irqchip, pass IRQ_TYPE_NONE
1691 * to have the core avoid setting up any default type in the hardware.
1692 * @threaded: whether this irqchip uses a nested thread handler
1693 * @lock_key: lockdep class for IRQ lock
1694 * @request_key: lockdep class for IRQ request
1696 * This function closely associates a certain irqchip with a certain
1697 * gpiochip, providing an irq domain to translate the local IRQs to
1698 * global irqs in the gpiolib core, and making sure that the gpiochip
1699 * is passed as chip data to all related functions. Driver callbacks
1700 * need to use gpiochip_get_data() to get their local state containers back
1701 * from the gpiochip passed as chip data. An irqdomain will be stored
1702 * in the gpiochip that shall be used by the driver to handle IRQ number
1703 * translation. The gpiochip will need to be initialized and registered
1704 * before calling this function.
1706 * This function will handle two cell:ed simple IRQs and assumes all
1707 * the pins on the gpiochip can generate a unique IRQ. Everything else
1708 * need to be open coded.
1710 int gpiochip_irqchip_add_key(struct gpio_chip *gc,
1711 struct irq_chip *irqchip,
1712 unsigned int first_irq,
1713 irq_flow_handler_t handler,
1716 struct lock_class_key *lock_key,
1717 struct lock_class_key *request_key)
1719 struct device_node *of_node;
1721 if (!gc || !irqchip)
1725 chip_err(gc, "missing gpiochip .dev parent pointer\n");
1728 gc->irq.threaded = threaded;
1729 of_node = gc->parent->of_node;
1730 #ifdef CONFIG_OF_GPIO
1732 * If the gpiochip has an assigned OF node this takes precedence
1733 * FIXME: get rid of this and use gc->parent->of_node
1737 of_node = gc->of_node;
1740 * Specifying a default trigger is a terrible idea if DT or ACPI is
1741 * used to configure the interrupts, as you may end-up with
1742 * conflicting triggers. Tell the user, and reset to NONE.
1744 if (WARN(of_node && type != IRQ_TYPE_NONE,
1745 "%pOF: Ignoring %d default trigger\n", of_node, type))
1746 type = IRQ_TYPE_NONE;
1747 if (has_acpi_companion(gc->parent) && type != IRQ_TYPE_NONE) {
1748 acpi_handle_warn(ACPI_HANDLE(gc->parent),
1749 "Ignoring %d default trigger\n", type);
1750 type = IRQ_TYPE_NONE;
1753 gc->irq.chip = irqchip;
1754 gc->irq.handler = handler;
1755 gc->irq.default_type = type;
1756 gc->to_irq = gpiochip_to_irq;
1757 gc->irq.lock_key = lock_key;
1758 gc->irq.request_key = request_key;
1759 gc->irq.domain = irq_domain_add_simple(of_node,
1760 gc->ngpio, first_irq,
1761 &gpiochip_domain_ops, gc);
1762 if (!gc->irq.domain) {
1763 gc->irq.chip = NULL;
1767 gpiochip_set_irq_hooks(gc);
1769 acpi_gpiochip_request_interrupts(gc);
1773 EXPORT_SYMBOL_GPL(gpiochip_irqchip_add_key);
1776 * gpiochip_irqchip_add_domain() - adds an irqdomain to a gpiochip
1777 * @gc: the gpiochip to add the irqchip to
1778 * @domain: the irqdomain to add to the gpiochip
1780 * This function adds an IRQ domain to the gpiochip.
1782 int gpiochip_irqchip_add_domain(struct gpio_chip *gc,
1783 struct irq_domain *domain)
1788 gc->to_irq = gpiochip_to_irq;
1789 gc->irq.domain = domain;
1793 EXPORT_SYMBOL_GPL(gpiochip_irqchip_add_domain);
1795 #else /* CONFIG_GPIOLIB_IRQCHIP */
1797 static inline int gpiochip_add_irqchip(struct gpio_chip *gc,
1798 struct lock_class_key *lock_key,
1799 struct lock_class_key *request_key)
1803 static void gpiochip_irqchip_remove(struct gpio_chip *gc) {}
1805 static inline int gpiochip_irqchip_init_hw(struct gpio_chip *gc)
1810 static inline int gpiochip_irqchip_init_valid_mask(struct gpio_chip *gc)
1814 static inline void gpiochip_irqchip_free_valid_mask(struct gpio_chip *gc)
1817 #endif /* CONFIG_GPIOLIB_IRQCHIP */
1820 * gpiochip_generic_request() - request the gpio function for a pin
1821 * @gc: the gpiochip owning the GPIO
1822 * @offset: the offset of the GPIO to request for GPIO function
1824 int gpiochip_generic_request(struct gpio_chip *gc, unsigned offset)
1826 #ifdef CONFIG_PINCTRL
1827 if (list_empty(&gc->gpiodev->pin_ranges))
1831 return pinctrl_gpio_request(gc->gpiodev->base + offset);
1833 EXPORT_SYMBOL_GPL(gpiochip_generic_request);
1836 * gpiochip_generic_free() - free the gpio function from a pin
1837 * @gc: the gpiochip to request the gpio function for
1838 * @offset: the offset of the GPIO to free from GPIO function
1840 void gpiochip_generic_free(struct gpio_chip *gc, unsigned offset)
1842 #ifdef CONFIG_PINCTRL
1843 if (list_empty(&gc->gpiodev->pin_ranges))
1847 pinctrl_gpio_free(gc->gpiodev->base + offset);
1849 EXPORT_SYMBOL_GPL(gpiochip_generic_free);
1852 * gpiochip_generic_config() - apply configuration for a pin
1853 * @gc: the gpiochip owning the GPIO
1854 * @offset: the offset of the GPIO to apply the configuration
1855 * @config: the configuration to be applied
1857 int gpiochip_generic_config(struct gpio_chip *gc, unsigned offset,
1858 unsigned long config)
1860 return pinctrl_gpio_set_config(gc->gpiodev->base + offset, config);
1862 EXPORT_SYMBOL_GPL(gpiochip_generic_config);
1864 #ifdef CONFIG_PINCTRL
1867 * gpiochip_add_pingroup_range() - add a range for GPIO <-> pin mapping
1868 * @gc: the gpiochip to add the range for
1869 * @pctldev: the pin controller to map to
1870 * @gpio_offset: the start offset in the current gpio_chip number space
1871 * @pin_group: name of the pin group inside the pin controller
1873 * Calling this function directly from a DeviceTree-supported
1874 * pinctrl driver is DEPRECATED. Please see Section 2.1 of
1875 * Documentation/devicetree/bindings/gpio/gpio.txt on how to
1876 * bind pinctrl and gpio drivers via the "gpio-ranges" property.
1878 int gpiochip_add_pingroup_range(struct gpio_chip *gc,
1879 struct pinctrl_dev *pctldev,
1880 unsigned int gpio_offset, const char *pin_group)
1882 struct gpio_pin_range *pin_range;
1883 struct gpio_device *gdev = gc->gpiodev;
1886 pin_range = kzalloc(sizeof(*pin_range), GFP_KERNEL);
1888 chip_err(gc, "failed to allocate pin ranges\n");
1892 /* Use local offset as range ID */
1893 pin_range->range.id = gpio_offset;
1894 pin_range->range.gc = gc;
1895 pin_range->range.name = gc->label;
1896 pin_range->range.base = gdev->base + gpio_offset;
1897 pin_range->pctldev = pctldev;
1899 ret = pinctrl_get_group_pins(pctldev, pin_group,
1900 &pin_range->range.pins,
1901 &pin_range->range.npins);
1907 pinctrl_add_gpio_range(pctldev, &pin_range->range);
1909 chip_dbg(gc, "created GPIO range %d->%d ==> %s PINGRP %s\n",
1910 gpio_offset, gpio_offset + pin_range->range.npins - 1,
1911 pinctrl_dev_get_devname(pctldev), pin_group);
1913 list_add_tail(&pin_range->node, &gdev->pin_ranges);
1917 EXPORT_SYMBOL_GPL(gpiochip_add_pingroup_range);
1920 * gpiochip_add_pin_range() - add a range for GPIO <-> pin mapping
1921 * @gc: the gpiochip to add the range for
1922 * @pinctl_name: the dev_name() of the pin controller to map to
1923 * @gpio_offset: the start offset in the current gpio_chip number space
1924 * @pin_offset: the start offset in the pin controller number space
1925 * @npins: the number of pins from the offset of each pin space (GPIO and
1926 * pin controller) to accumulate in this range
1929 * 0 on success, or a negative error-code on failure.
1931 * Calling this function directly from a DeviceTree-supported
1932 * pinctrl driver is DEPRECATED. Please see Section 2.1 of
1933 * Documentation/devicetree/bindings/gpio/gpio.txt on how to
1934 * bind pinctrl and gpio drivers via the "gpio-ranges" property.
1936 int gpiochip_add_pin_range(struct gpio_chip *gc, const char *pinctl_name,
1937 unsigned int gpio_offset, unsigned int pin_offset,
1940 struct gpio_pin_range *pin_range;
1941 struct gpio_device *gdev = gc->gpiodev;
1944 pin_range = kzalloc(sizeof(*pin_range), GFP_KERNEL);
1946 chip_err(gc, "failed to allocate pin ranges\n");
1950 /* Use local offset as range ID */
1951 pin_range->range.id = gpio_offset;
1952 pin_range->range.gc = gc;
1953 pin_range->range.name = gc->label;
1954 pin_range->range.base = gdev->base + gpio_offset;
1955 pin_range->range.pin_base = pin_offset;
1956 pin_range->range.npins = npins;
1957 pin_range->pctldev = pinctrl_find_and_add_gpio_range(pinctl_name,
1959 if (IS_ERR(pin_range->pctldev)) {
1960 ret = PTR_ERR(pin_range->pctldev);
1961 chip_err(gc, "could not create pin range\n");
1965 chip_dbg(gc, "created GPIO range %d->%d ==> %s PIN %d->%d\n",
1966 gpio_offset, gpio_offset + npins - 1,
1968 pin_offset, pin_offset + npins - 1);
1970 list_add_tail(&pin_range->node, &gdev->pin_ranges);
1974 EXPORT_SYMBOL_GPL(gpiochip_add_pin_range);
1977 * gpiochip_remove_pin_ranges() - remove all the GPIO <-> pin mappings
1978 * @gc: the chip to remove all the mappings for
1980 void gpiochip_remove_pin_ranges(struct gpio_chip *gc)
1982 struct gpio_pin_range *pin_range, *tmp;
1983 struct gpio_device *gdev = gc->gpiodev;
1985 list_for_each_entry_safe(pin_range, tmp, &gdev->pin_ranges, node) {
1986 list_del(&pin_range->node);
1987 pinctrl_remove_gpio_range(pin_range->pctldev,
1992 EXPORT_SYMBOL_GPL(gpiochip_remove_pin_ranges);
1994 #endif /* CONFIG_PINCTRL */
1996 /* These "optional" allocation calls help prevent drivers from stomping
1997 * on each other, and help provide better diagnostics in debugfs.
1998 * They're called even less than the "set direction" calls.
2000 static int gpiod_request_commit(struct gpio_desc *desc, const char *label)
2002 struct gpio_chip *gc = desc->gdev->chip;
2004 unsigned long flags;
2008 label = kstrdup_const(label, GFP_KERNEL);
2013 spin_lock_irqsave(&gpio_lock, flags);
2015 /* NOTE: gpio_request() can be called in early boot,
2016 * before IRQs are enabled, for non-sleeping (SOC) GPIOs.
2019 if (test_and_set_bit(FLAG_REQUESTED, &desc->flags) == 0) {
2020 desc_set_label(desc, label ? : "?");
2029 /* gc->request may sleep */
2030 spin_unlock_irqrestore(&gpio_lock, flags);
2031 offset = gpio_chip_hwgpio(desc);
2032 if (gpiochip_line_is_valid(gc, offset))
2033 ret = gc->request(gc, offset);
2036 spin_lock_irqsave(&gpio_lock, flags);
2039 desc_set_label(desc, NULL);
2041 clear_bit(FLAG_REQUESTED, &desc->flags);
2045 if (gc->get_direction) {
2046 /* gc->get_direction may sleep */
2047 spin_unlock_irqrestore(&gpio_lock, flags);
2048 gpiod_get_direction(desc);
2049 spin_lock_irqsave(&gpio_lock, flags);
2052 spin_unlock_irqrestore(&gpio_lock, flags);
2057 * This descriptor validation needs to be inserted verbatim into each
2058 * function taking a descriptor, so we need to use a preprocessor
2059 * macro to avoid endless duplication. If the desc is NULL it is an
2060 * optional GPIO and calls should just bail out.
2062 static int validate_desc(const struct gpio_desc *desc, const char *func)
2067 pr_warn("%s: invalid GPIO (errorpointer)\n", func);
2068 return PTR_ERR(desc);
2071 pr_warn("%s: invalid GPIO (no device)\n", func);
2074 if (!desc->gdev->chip) {
2075 dev_warn(&desc->gdev->dev,
2076 "%s: backing chip is gone\n", func);
2082 #define VALIDATE_DESC(desc) do { \
2083 int __valid = validate_desc(desc, __func__); \
2088 #define VALIDATE_DESC_VOID(desc) do { \
2089 int __valid = validate_desc(desc, __func__); \
2094 int gpiod_request(struct gpio_desc *desc, const char *label)
2096 int ret = -EPROBE_DEFER;
2097 struct gpio_device *gdev;
2099 VALIDATE_DESC(desc);
2102 if (try_module_get(gdev->owner)) {
2103 ret = gpiod_request_commit(desc, label);
2105 module_put(gdev->owner);
2107 get_device(&gdev->dev);
2111 gpiod_dbg(desc, "%s: status %d\n", __func__, ret);
2116 static bool gpiod_free_commit(struct gpio_desc *desc)
2119 unsigned long flags;
2120 struct gpio_chip *gc;
2124 gpiod_unexport(desc);
2126 spin_lock_irqsave(&gpio_lock, flags);
2128 gc = desc->gdev->chip;
2129 if (gc && test_bit(FLAG_REQUESTED, &desc->flags)) {
2131 spin_unlock_irqrestore(&gpio_lock, flags);
2132 might_sleep_if(gc->can_sleep);
2133 gc->free(gc, gpio_chip_hwgpio(desc));
2134 spin_lock_irqsave(&gpio_lock, flags);
2136 kfree_const(desc->label);
2137 desc_set_label(desc, NULL);
2138 clear_bit(FLAG_ACTIVE_LOW, &desc->flags);
2139 clear_bit(FLAG_REQUESTED, &desc->flags);
2140 clear_bit(FLAG_OPEN_DRAIN, &desc->flags);
2141 clear_bit(FLAG_OPEN_SOURCE, &desc->flags);
2142 clear_bit(FLAG_PULL_UP, &desc->flags);
2143 clear_bit(FLAG_PULL_DOWN, &desc->flags);
2144 clear_bit(FLAG_BIAS_DISABLE, &desc->flags);
2145 clear_bit(FLAG_EDGE_RISING, &desc->flags);
2146 clear_bit(FLAG_EDGE_FALLING, &desc->flags);
2147 clear_bit(FLAG_IS_HOGGED, &desc->flags);
2148 #ifdef CONFIG_OF_DYNAMIC
2151 #ifdef CONFIG_GPIO_CDEV
2152 WRITE_ONCE(desc->debounce_period_us, 0);
2157 spin_unlock_irqrestore(&gpio_lock, flags);
2158 blocking_notifier_call_chain(&desc->gdev->notifier,
2159 GPIOLINE_CHANGED_RELEASED, desc);
2164 void gpiod_free(struct gpio_desc *desc)
2166 if (desc && desc->gdev && gpiod_free_commit(desc)) {
2167 module_put(desc->gdev->owner);
2168 put_device(&desc->gdev->dev);
2170 WARN_ON(extra_checks);
2175 * gpiochip_is_requested - return string iff signal was requested
2176 * @gc: controller managing the signal
2177 * @offset: of signal within controller's 0..(ngpio - 1) range
2179 * Returns NULL if the GPIO is not currently requested, else a string.
2180 * The string returned is the label passed to gpio_request(); if none has been
2181 * passed it is a meaningless, non-NULL constant.
2183 * This function is for use by GPIO controller drivers. The label can
2184 * help with diagnostics, and knowing that the signal is used as a GPIO
2185 * can help avoid accidentally multiplexing it to another controller.
2187 const char *gpiochip_is_requested(struct gpio_chip *gc, unsigned offset)
2189 struct gpio_desc *desc;
2191 if (offset >= gc->ngpio)
2194 desc = gpiochip_get_desc(gc, offset);
2198 if (test_bit(FLAG_REQUESTED, &desc->flags) == 0)
2202 EXPORT_SYMBOL_GPL(gpiochip_is_requested);
2205 * gpiochip_request_own_desc - Allow GPIO chip to request its own descriptor
2207 * @hwnum: hardware number of the GPIO for which to request the descriptor
2208 * @label: label for the GPIO
2209 * @lflags: lookup flags for this GPIO or 0 if default, this can be used to
2210 * specify things like line inversion semantics with the machine flags
2211 * such as GPIO_OUT_LOW
2212 * @dflags: descriptor request flags for this GPIO or 0 if default, this
2213 * can be used to specify consumer semantics such as open drain
2215 * Function allows GPIO chip drivers to request and use their own GPIO
2216 * descriptors via gpiolib API. Difference to gpiod_request() is that this
2217 * function will not increase reference count of the GPIO chip module. This
2218 * allows the GPIO chip module to be unloaded as needed (we assume that the
2219 * GPIO chip driver handles freeing the GPIOs it has requested).
2222 * A pointer to the GPIO descriptor, or an ERR_PTR()-encoded negative error
2225 struct gpio_desc *gpiochip_request_own_desc(struct gpio_chip *gc,
2228 enum gpio_lookup_flags lflags,
2229 enum gpiod_flags dflags)
2231 struct gpio_desc *desc = gpiochip_get_desc(gc, hwnum);
2235 chip_err(gc, "failed to get GPIO descriptor\n");
2239 ret = gpiod_request_commit(desc, label);
2241 return ERR_PTR(ret);
2243 ret = gpiod_configure_flags(desc, label, lflags, dflags);
2245 chip_err(gc, "setup of own GPIO %s failed\n", label);
2246 gpiod_free_commit(desc);
2247 return ERR_PTR(ret);
2252 EXPORT_SYMBOL_GPL(gpiochip_request_own_desc);
2255 * gpiochip_free_own_desc - Free GPIO requested by the chip driver
2256 * @desc: GPIO descriptor to free
2258 * Function frees the given GPIO requested previously with
2259 * gpiochip_request_own_desc().
2261 void gpiochip_free_own_desc(struct gpio_desc *desc)
2264 gpiod_free_commit(desc);
2266 EXPORT_SYMBOL_GPL(gpiochip_free_own_desc);
2269 * Drivers MUST set GPIO direction before making get/set calls. In
2270 * some cases this is done in early boot, before IRQs are enabled.
2272 * As a rule these aren't called more than once (except for drivers
2273 * using the open-drain emulation idiom) so these are natural places
2274 * to accumulate extra debugging checks. Note that we can't (yet)
2275 * rely on gpio_request() having been called beforehand.
2278 static int gpio_do_set_config(struct gpio_chip *gc, unsigned int offset,
2279 unsigned long config)
2281 if (!gc->set_config)
2284 return gc->set_config(gc, offset, config);
2287 static int gpio_set_config(struct gpio_desc *desc, enum pin_config_param mode)
2289 struct gpio_chip *gc = desc->gdev->chip;
2290 unsigned long config;
2294 case PIN_CONFIG_BIAS_PULL_DOWN:
2295 case PIN_CONFIG_BIAS_PULL_UP:
2303 config = PIN_CONF_PACKED(mode, arg);
2304 return gpio_do_set_config(gc, gpio_chip_hwgpio(desc), config);
2307 static int gpio_set_bias(struct gpio_desc *desc)
2312 if (test_bit(FLAG_BIAS_DISABLE, &desc->flags))
2313 bias = PIN_CONFIG_BIAS_DISABLE;
2314 else if (test_bit(FLAG_PULL_UP, &desc->flags))
2315 bias = PIN_CONFIG_BIAS_PULL_UP;
2316 else if (test_bit(FLAG_PULL_DOWN, &desc->flags))
2317 bias = PIN_CONFIG_BIAS_PULL_DOWN;
2320 ret = gpio_set_config(desc, bias);
2321 if (ret != -ENOTSUPP)
2328 * gpiod_direction_input - set the GPIO direction to input
2329 * @desc: GPIO to set to input
2331 * Set the direction of the passed GPIO to input, such as gpiod_get_value() can
2332 * be called safely on it.
2334 * Return 0 in case of success, else an error code.
2336 int gpiod_direction_input(struct gpio_desc *desc)
2338 struct gpio_chip *gc;
2341 VALIDATE_DESC(desc);
2342 gc = desc->gdev->chip;
2345 * It is legal to have no .get() and .direction_input() specified if
2346 * the chip is output-only, but you can't specify .direction_input()
2347 * and not support the .get() operation, that doesn't make sense.
2349 if (!gc->get && gc->direction_input) {
2351 "%s: missing get() but have direction_input()\n",
2357 * If we have a .direction_input() callback, things are simple,
2358 * just call it. Else we are some input-only chip so try to check the
2359 * direction (if .get_direction() is supported) else we silently
2360 * assume we are in input mode after this.
2362 if (gc->direction_input) {
2363 ret = gc->direction_input(gc, gpio_chip_hwgpio(desc));
2364 } else if (gc->get_direction &&
2365 (gc->get_direction(gc, gpio_chip_hwgpio(desc)) != 1)) {
2367 "%s: missing direction_input() operation and line is output\n",
2372 clear_bit(FLAG_IS_OUT, &desc->flags);
2373 ret = gpio_set_bias(desc);
2376 trace_gpio_direction(desc_to_gpio(desc), 1, ret);
2380 EXPORT_SYMBOL_GPL(gpiod_direction_input);
2382 static int gpiod_direction_output_raw_commit(struct gpio_desc *desc, int value)
2384 struct gpio_chip *gc = desc->gdev->chip;
2389 * It's OK not to specify .direction_output() if the gpiochip is
2390 * output-only, but if there is then not even a .set() operation it
2391 * is pretty tricky to drive the output line.
2393 if (!gc->set && !gc->direction_output) {
2395 "%s: missing set() and direction_output() operations\n",
2400 if (gc->direction_output) {
2401 ret = gc->direction_output(gc, gpio_chip_hwgpio(desc), val);
2403 /* Check that we are in output mode if we can */
2404 if (gc->get_direction &&
2405 gc->get_direction(gc, gpio_chip_hwgpio(desc))) {
2407 "%s: missing direction_output() operation\n",
2412 * If we can't actively set the direction, we are some
2413 * output-only chip, so just drive the output as desired.
2415 gc->set(gc, gpio_chip_hwgpio(desc), val);
2419 set_bit(FLAG_IS_OUT, &desc->flags);
2420 trace_gpio_value(desc_to_gpio(desc), 0, val);
2421 trace_gpio_direction(desc_to_gpio(desc), 0, ret);
2426 * gpiod_direction_output_raw - set the GPIO direction to output
2427 * @desc: GPIO to set to output
2428 * @value: initial output value of the GPIO
2430 * Set the direction of the passed GPIO to output, such as gpiod_set_value() can
2431 * be called safely on it. The initial value of the output must be specified
2432 * as raw value on the physical line without regard for the ACTIVE_LOW status.
2434 * Return 0 in case of success, else an error code.
2436 int gpiod_direction_output_raw(struct gpio_desc *desc, int value)
2438 VALIDATE_DESC(desc);
2439 return gpiod_direction_output_raw_commit(desc, value);
2441 EXPORT_SYMBOL_GPL(gpiod_direction_output_raw);
2444 * gpiod_direction_output - set the GPIO direction to output
2445 * @desc: GPIO to set to output
2446 * @value: initial output value of the GPIO
2448 * Set the direction of the passed GPIO to output, such as gpiod_set_value() can
2449 * be called safely on it. The initial value of the output must be specified
2450 * as the logical value of the GPIO, i.e. taking its ACTIVE_LOW status into
2453 * Return 0 in case of success, else an error code.
2455 int gpiod_direction_output(struct gpio_desc *desc, int value)
2459 VALIDATE_DESC(desc);
2460 if (test_bit(FLAG_ACTIVE_LOW, &desc->flags))
2465 /* GPIOs used for enabled IRQs shall not be set as output */
2466 if (test_bit(FLAG_USED_AS_IRQ, &desc->flags) &&
2467 test_bit(FLAG_IRQ_IS_ENABLED, &desc->flags)) {
2469 "%s: tried to set a GPIO tied to an IRQ as output\n",
2474 if (test_bit(FLAG_OPEN_DRAIN, &desc->flags)) {
2475 /* First see if we can enable open drain in hardware */
2476 ret = gpio_set_config(desc, PIN_CONFIG_DRIVE_OPEN_DRAIN);
2478 goto set_output_value;
2479 /* Emulate open drain by not actively driving the line high */
2481 ret = gpiod_direction_input(desc);
2482 goto set_output_flag;
2485 else if (test_bit(FLAG_OPEN_SOURCE, &desc->flags)) {
2486 ret = gpio_set_config(desc, PIN_CONFIG_DRIVE_OPEN_SOURCE);
2488 goto set_output_value;
2489 /* Emulate open source by not actively driving the line low */
2491 ret = gpiod_direction_input(desc);
2492 goto set_output_flag;
2495 gpio_set_config(desc, PIN_CONFIG_DRIVE_PUSH_PULL);
2499 ret = gpio_set_bias(desc);
2502 return gpiod_direction_output_raw_commit(desc, value);
2506 * When emulating open-source or open-drain functionalities by not
2507 * actively driving the line (setting mode to input) we still need to
2508 * set the IS_OUT flag or otherwise we won't be able to set the line
2512 set_bit(FLAG_IS_OUT, &desc->flags);
2515 EXPORT_SYMBOL_GPL(gpiod_direction_output);
2518 * gpiod_set_config - sets @config for a GPIO
2519 * @desc: descriptor of the GPIO for which to set the configuration
2520 * @config: Same packed config format as generic pinconf
2523 * 0 on success, %-ENOTSUPP if the controller doesn't support setting the
2526 int gpiod_set_config(struct gpio_desc *desc, unsigned long config)
2528 struct gpio_chip *gc;
2530 VALIDATE_DESC(desc);
2531 gc = desc->gdev->chip;
2533 return gpio_do_set_config(gc, gpio_chip_hwgpio(desc), config);
2535 EXPORT_SYMBOL_GPL(gpiod_set_config);
2538 * gpiod_set_debounce - sets @debounce time for a GPIO
2539 * @desc: descriptor of the GPIO for which to set debounce time
2540 * @debounce: debounce time in microseconds
2543 * 0 on success, %-ENOTSUPP if the controller doesn't support setting the
2546 int gpiod_set_debounce(struct gpio_desc *desc, unsigned debounce)
2548 unsigned long config;
2550 config = pinconf_to_config_packed(PIN_CONFIG_INPUT_DEBOUNCE, debounce);
2551 return gpiod_set_config(desc, config);
2553 EXPORT_SYMBOL_GPL(gpiod_set_debounce);
2556 * gpiod_set_transitory - Lose or retain GPIO state on suspend or reset
2557 * @desc: descriptor of the GPIO for which to configure persistence
2558 * @transitory: True to lose state on suspend or reset, false for persistence
2561 * 0 on success, otherwise a negative error code.
2563 int gpiod_set_transitory(struct gpio_desc *desc, bool transitory)
2565 struct gpio_chip *gc;
2566 unsigned long packed;
2570 VALIDATE_DESC(desc);
2572 * Handle FLAG_TRANSITORY first, enabling queries to gpiolib for
2573 * persistence state.
2575 assign_bit(FLAG_TRANSITORY, &desc->flags, transitory);
2577 /* If the driver supports it, set the persistence state now */
2578 gc = desc->gdev->chip;
2579 if (!gc->set_config)
2582 packed = pinconf_to_config_packed(PIN_CONFIG_PERSIST_STATE,
2584 gpio = gpio_chip_hwgpio(desc);
2585 rc = gpio_do_set_config(gc, gpio, packed);
2586 if (rc == -ENOTSUPP) {
2587 dev_dbg(&desc->gdev->dev, "Persistence not supported for GPIO %d\n",
2594 EXPORT_SYMBOL_GPL(gpiod_set_transitory);
2597 * gpiod_is_active_low - test whether a GPIO is active-low or not
2598 * @desc: the gpio descriptor to test
2600 * Returns 1 if the GPIO is active-low, 0 otherwise.
2602 int gpiod_is_active_low(const struct gpio_desc *desc)
2604 VALIDATE_DESC(desc);
2605 return test_bit(FLAG_ACTIVE_LOW, &desc->flags);
2607 EXPORT_SYMBOL_GPL(gpiod_is_active_low);
2610 * gpiod_toggle_active_low - toggle whether a GPIO is active-low or not
2611 * @desc: the gpio descriptor to change
2613 void gpiod_toggle_active_low(struct gpio_desc *desc)
2615 VALIDATE_DESC_VOID(desc);
2616 change_bit(FLAG_ACTIVE_LOW, &desc->flags);
2618 EXPORT_SYMBOL_GPL(gpiod_toggle_active_low);
2620 /* I/O calls are only valid after configuration completed; the relevant
2621 * "is this a valid GPIO" error checks should already have been done.
2623 * "Get" operations are often inlinable as reading a pin value register,
2624 * and masking the relevant bit in that register.
2626 * When "set" operations are inlinable, they involve writing that mask to
2627 * one register to set a low value, or a different register to set it high.
2628 * Otherwise locking is needed, so there may be little value to inlining.
2630 *------------------------------------------------------------------------
2632 * IMPORTANT!!! The hot paths -- get/set value -- assume that callers
2633 * have requested the GPIO. That can include implicit requesting by
2634 * a direction setting call. Marking a gpio as requested locks its chip
2635 * in memory, guaranteeing that these table lookups need no more locking
2636 * and that gpiochip_remove() will fail.
2638 * REVISIT when debugging, consider adding some instrumentation to ensure
2639 * that the GPIO was actually requested.
2642 static int gpiod_get_raw_value_commit(const struct gpio_desc *desc)
2644 struct gpio_chip *gc;
2648 gc = desc->gdev->chip;
2649 offset = gpio_chip_hwgpio(desc);
2650 value = gc->get ? gc->get(gc, offset) : -EIO;
2651 value = value < 0 ? value : !!value;
2652 trace_gpio_value(desc_to_gpio(desc), 1, value);
2656 static int gpio_chip_get_multiple(struct gpio_chip *gc,
2657 unsigned long *mask, unsigned long *bits)
2659 if (gc->get_multiple) {
2660 return gc->get_multiple(gc, mask, bits);
2661 } else if (gc->get) {
2664 for_each_set_bit(i, mask, gc->ngpio) {
2665 value = gc->get(gc, i);
2668 __assign_bit(i, bits, value);
2675 int gpiod_get_array_value_complex(bool raw, bool can_sleep,
2676 unsigned int array_size,
2677 struct gpio_desc **desc_array,
2678 struct gpio_array *array_info,
2679 unsigned long *value_bitmap)
2684 * Validate array_info against desc_array and its size.
2685 * It should immediately follow desc_array if both
2686 * have been obtained from the same gpiod_get_array() call.
2688 if (array_info && array_info->desc == desc_array &&
2689 array_size <= array_info->size &&
2690 (void *)array_info == desc_array + array_info->size) {
2692 WARN_ON(array_info->chip->can_sleep);
2694 ret = gpio_chip_get_multiple(array_info->chip,
2695 array_info->get_mask,
2700 if (!raw && !bitmap_empty(array_info->invert_mask, array_size))
2701 bitmap_xor(value_bitmap, value_bitmap,
2702 array_info->invert_mask, array_size);
2704 i = find_first_zero_bit(array_info->get_mask, array_size);
2705 if (i == array_size)
2711 while (i < array_size) {
2712 struct gpio_chip *gc = desc_array[i]->gdev->chip;
2713 unsigned long fastpath[2 * BITS_TO_LONGS(FASTPATH_NGPIO)];
2714 unsigned long *mask, *bits;
2717 if (likely(gc->ngpio <= FASTPATH_NGPIO)) {
2720 mask = kmalloc_array(2 * BITS_TO_LONGS(gc->ngpio),
2722 can_sleep ? GFP_KERNEL : GFP_ATOMIC);
2727 bits = mask + BITS_TO_LONGS(gc->ngpio);
2728 bitmap_zero(mask, gc->ngpio);
2731 WARN_ON(gc->can_sleep);
2733 /* collect all inputs belonging to the same chip */
2736 const struct gpio_desc *desc = desc_array[i];
2737 int hwgpio = gpio_chip_hwgpio(desc);
2739 __set_bit(hwgpio, mask);
2743 i = find_next_zero_bit(array_info->get_mask,
2745 } while ((i < array_size) &&
2746 (desc_array[i]->gdev->chip == gc));
2748 ret = gpio_chip_get_multiple(gc, mask, bits);
2750 if (mask != fastpath)
2755 for (j = first; j < i; ) {
2756 const struct gpio_desc *desc = desc_array[j];
2757 int hwgpio = gpio_chip_hwgpio(desc);
2758 int value = test_bit(hwgpio, bits);
2760 if (!raw && test_bit(FLAG_ACTIVE_LOW, &desc->flags))
2762 __assign_bit(j, value_bitmap, value);
2763 trace_gpio_value(desc_to_gpio(desc), 1, value);
2767 j = find_next_zero_bit(array_info->get_mask, i,
2771 if (mask != fastpath)
2778 * gpiod_get_raw_value() - return a gpio's raw value
2779 * @desc: gpio whose value will be returned
2781 * Return the GPIO's raw value, i.e. the value of the physical line disregarding
2782 * its ACTIVE_LOW status, or negative errno on failure.
2784 * This function can be called from contexts where we cannot sleep, and will
2785 * complain if the GPIO chip functions potentially sleep.
2787 int gpiod_get_raw_value(const struct gpio_desc *desc)
2789 VALIDATE_DESC(desc);
2790 /* Should be using gpiod_get_raw_value_cansleep() */
2791 WARN_ON(desc->gdev->chip->can_sleep);
2792 return gpiod_get_raw_value_commit(desc);
2794 EXPORT_SYMBOL_GPL(gpiod_get_raw_value);
2797 * gpiod_get_value() - return a gpio's value
2798 * @desc: gpio whose value will be returned
2800 * Return the GPIO's logical value, i.e. taking the ACTIVE_LOW status into
2801 * account, or negative errno on failure.
2803 * This function can be called from contexts where we cannot sleep, and will
2804 * complain if the GPIO chip functions potentially sleep.
2806 int gpiod_get_value(const struct gpio_desc *desc)
2810 VALIDATE_DESC(desc);
2811 /* Should be using gpiod_get_value_cansleep() */
2812 WARN_ON(desc->gdev->chip->can_sleep);
2814 value = gpiod_get_raw_value_commit(desc);
2818 if (test_bit(FLAG_ACTIVE_LOW, &desc->flags))
2823 EXPORT_SYMBOL_GPL(gpiod_get_value);
2826 * gpiod_get_raw_array_value() - read raw values from an array of GPIOs
2827 * @array_size: number of elements in the descriptor array / value bitmap
2828 * @desc_array: array of GPIO descriptors whose values will be read
2829 * @array_info: information on applicability of fast bitmap processing path
2830 * @value_bitmap: bitmap to store the read values
2832 * Read the raw values of the GPIOs, i.e. the values of the physical lines
2833 * without regard for their ACTIVE_LOW status. Return 0 in case of success,
2834 * else an error code.
2836 * This function can be called from contexts where we cannot sleep,
2837 * and it will complain if the GPIO chip functions potentially sleep.
2839 int gpiod_get_raw_array_value(unsigned int array_size,
2840 struct gpio_desc **desc_array,
2841 struct gpio_array *array_info,
2842 unsigned long *value_bitmap)
2846 return gpiod_get_array_value_complex(true, false, array_size,
2847 desc_array, array_info,
2850 EXPORT_SYMBOL_GPL(gpiod_get_raw_array_value);
2853 * gpiod_get_array_value() - read values from an array of GPIOs
2854 * @array_size: number of elements in the descriptor array / value bitmap
2855 * @desc_array: array of GPIO descriptors whose values will be read
2856 * @array_info: information on applicability of fast bitmap processing path
2857 * @value_bitmap: bitmap to store the read values
2859 * Read the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status
2860 * into account. Return 0 in case of success, else an error code.
2862 * This function can be called from contexts where we cannot sleep,
2863 * and it will complain if the GPIO chip functions potentially sleep.
2865 int gpiod_get_array_value(unsigned int array_size,
2866 struct gpio_desc **desc_array,
2867 struct gpio_array *array_info,
2868 unsigned long *value_bitmap)
2872 return gpiod_get_array_value_complex(false, false, array_size,
2873 desc_array, array_info,
2876 EXPORT_SYMBOL_GPL(gpiod_get_array_value);
2879 * gpio_set_open_drain_value_commit() - Set the open drain gpio's value.
2880 * @desc: gpio descriptor whose state need to be set.
2881 * @value: Non-zero for setting it HIGH otherwise it will set to LOW.
2883 static void gpio_set_open_drain_value_commit(struct gpio_desc *desc, bool value)
2886 struct gpio_chip *gc = desc->gdev->chip;
2887 int offset = gpio_chip_hwgpio(desc);
2890 ret = gc->direction_input(gc, offset);
2892 ret = gc->direction_output(gc, offset, 0);
2894 set_bit(FLAG_IS_OUT, &desc->flags);
2896 trace_gpio_direction(desc_to_gpio(desc), value, ret);
2899 "%s: Error in set_value for open drain err %d\n",
2904 * _gpio_set_open_source_value() - Set the open source gpio's value.
2905 * @desc: gpio descriptor whose state need to be set.
2906 * @value: Non-zero for setting it HIGH otherwise it will set to LOW.
2908 static void gpio_set_open_source_value_commit(struct gpio_desc *desc, bool value)
2911 struct gpio_chip *gc = desc->gdev->chip;
2912 int offset = gpio_chip_hwgpio(desc);
2915 ret = gc->direction_output(gc, offset, 1);
2917 set_bit(FLAG_IS_OUT, &desc->flags);
2919 ret = gc->direction_input(gc, offset);
2921 trace_gpio_direction(desc_to_gpio(desc), !value, ret);
2924 "%s: Error in set_value for open source err %d\n",
2928 static void gpiod_set_raw_value_commit(struct gpio_desc *desc, bool value)
2930 struct gpio_chip *gc;
2932 gc = desc->gdev->chip;
2933 trace_gpio_value(desc_to_gpio(desc), 0, value);
2934 gc->set(gc, gpio_chip_hwgpio(desc), value);
2938 * set multiple outputs on the same chip;
2939 * use the chip's set_multiple function if available;
2940 * otherwise set the outputs sequentially;
2941 * @chip: the GPIO chip we operate on
2942 * @mask: bit mask array; one bit per output; BITS_PER_LONG bits per word
2943 * defines which outputs are to be changed
2944 * @bits: bit value array; one bit per output; BITS_PER_LONG bits per word
2945 * defines the values the outputs specified by mask are to be set to
2947 static void gpio_chip_set_multiple(struct gpio_chip *gc,
2948 unsigned long *mask, unsigned long *bits)
2950 if (gc->set_multiple) {
2951 gc->set_multiple(gc, mask, bits);
2955 /* set outputs if the corresponding mask bit is set */
2956 for_each_set_bit(i, mask, gc->ngpio)
2957 gc->set(gc, i, test_bit(i, bits));
2961 int gpiod_set_array_value_complex(bool raw, bool can_sleep,
2962 unsigned int array_size,
2963 struct gpio_desc **desc_array,
2964 struct gpio_array *array_info,
2965 unsigned long *value_bitmap)
2970 * Validate array_info against desc_array and its size.
2971 * It should immediately follow desc_array if both
2972 * have been obtained from the same gpiod_get_array() call.
2974 if (array_info && array_info->desc == desc_array &&
2975 array_size <= array_info->size &&
2976 (void *)array_info == desc_array + array_info->size) {
2978 WARN_ON(array_info->chip->can_sleep);
2980 if (!raw && !bitmap_empty(array_info->invert_mask, array_size))
2981 bitmap_xor(value_bitmap, value_bitmap,
2982 array_info->invert_mask, array_size);
2984 gpio_chip_set_multiple(array_info->chip, array_info->set_mask,
2987 i = find_first_zero_bit(array_info->set_mask, array_size);
2988 if (i == array_size)
2994 while (i < array_size) {
2995 struct gpio_chip *gc = desc_array[i]->gdev->chip;
2996 unsigned long fastpath[2 * BITS_TO_LONGS(FASTPATH_NGPIO)];
2997 unsigned long *mask, *bits;
3000 if (likely(gc->ngpio <= FASTPATH_NGPIO)) {
3003 mask = kmalloc_array(2 * BITS_TO_LONGS(gc->ngpio),
3005 can_sleep ? GFP_KERNEL : GFP_ATOMIC);
3010 bits = mask + BITS_TO_LONGS(gc->ngpio);
3011 bitmap_zero(mask, gc->ngpio);
3014 WARN_ON(gc->can_sleep);
3017 struct gpio_desc *desc = desc_array[i];
3018 int hwgpio = gpio_chip_hwgpio(desc);
3019 int value = test_bit(i, value_bitmap);
3022 * Pins applicable for fast input but not for
3023 * fast output processing may have been already
3024 * inverted inside the fast path, skip them.
3026 if (!raw && !(array_info &&
3027 test_bit(i, array_info->invert_mask)) &&
3028 test_bit(FLAG_ACTIVE_LOW, &desc->flags))
3030 trace_gpio_value(desc_to_gpio(desc), 0, value);
3032 * collect all normal outputs belonging to the same chip
3033 * open drain and open source outputs are set individually
3035 if (test_bit(FLAG_OPEN_DRAIN, &desc->flags) && !raw) {
3036 gpio_set_open_drain_value_commit(desc, value);
3037 } else if (test_bit(FLAG_OPEN_SOURCE, &desc->flags) && !raw) {
3038 gpio_set_open_source_value_commit(desc, value);
3040 __set_bit(hwgpio, mask);
3041 __assign_bit(hwgpio, bits, value);
3047 i = find_next_zero_bit(array_info->set_mask,
3049 } while ((i < array_size) &&
3050 (desc_array[i]->gdev->chip == gc));
3051 /* push collected bits to outputs */
3053 gpio_chip_set_multiple(gc, mask, bits);
3055 if (mask != fastpath)
3062 * gpiod_set_raw_value() - assign a gpio's raw value
3063 * @desc: gpio whose value will be assigned
3064 * @value: value to assign
3066 * Set the raw value of the GPIO, i.e. the value of its physical line without
3067 * regard for its ACTIVE_LOW status.
3069 * This function can be called from contexts where we cannot sleep, and will
3070 * complain if the GPIO chip functions potentially sleep.
3072 void gpiod_set_raw_value(struct gpio_desc *desc, int value)
3074 VALIDATE_DESC_VOID(desc);
3075 /* Should be using gpiod_set_raw_value_cansleep() */
3076 WARN_ON(desc->gdev->chip->can_sleep);
3077 gpiod_set_raw_value_commit(desc, value);
3079 EXPORT_SYMBOL_GPL(gpiod_set_raw_value);
3082 * gpiod_set_value_nocheck() - set a GPIO line value without checking
3083 * @desc: the descriptor to set the value on
3084 * @value: value to set
3086 * This sets the value of a GPIO line backing a descriptor, applying
3087 * different semantic quirks like active low and open drain/source
3090 static void gpiod_set_value_nocheck(struct gpio_desc *desc, int value)
3092 if (test_bit(FLAG_ACTIVE_LOW, &desc->flags))
3094 if (test_bit(FLAG_OPEN_DRAIN, &desc->flags))
3095 gpio_set_open_drain_value_commit(desc, value);
3096 else if (test_bit(FLAG_OPEN_SOURCE, &desc->flags))
3097 gpio_set_open_source_value_commit(desc, value);
3099 gpiod_set_raw_value_commit(desc, value);
3103 * gpiod_set_value() - assign a gpio's value
3104 * @desc: gpio whose value will be assigned
3105 * @value: value to assign
3107 * Set the logical value of the GPIO, i.e. taking its ACTIVE_LOW,
3108 * OPEN_DRAIN and OPEN_SOURCE flags into account.
3110 * This function can be called from contexts where we cannot sleep, and will
3111 * complain if the GPIO chip functions potentially sleep.
3113 void gpiod_set_value(struct gpio_desc *desc, int value)
3115 VALIDATE_DESC_VOID(desc);
3116 /* Should be using gpiod_set_value_cansleep() */
3117 WARN_ON(desc->gdev->chip->can_sleep);
3118 gpiod_set_value_nocheck(desc, value);
3120 EXPORT_SYMBOL_GPL(gpiod_set_value);
3123 * gpiod_set_raw_array_value() - assign values to an array of GPIOs
3124 * @array_size: number of elements in the descriptor array / value bitmap
3125 * @desc_array: array of GPIO descriptors whose values will be assigned
3126 * @array_info: information on applicability of fast bitmap processing path
3127 * @value_bitmap: bitmap of values to assign
3129 * Set the raw values of the GPIOs, i.e. the values of the physical lines
3130 * without regard for their ACTIVE_LOW status.
3132 * This function can be called from contexts where we cannot sleep, and will
3133 * complain if the GPIO chip functions potentially sleep.
3135 int gpiod_set_raw_array_value(unsigned int array_size,
3136 struct gpio_desc **desc_array,
3137 struct gpio_array *array_info,
3138 unsigned long *value_bitmap)
3142 return gpiod_set_array_value_complex(true, false, array_size,
3143 desc_array, array_info, value_bitmap);
3145 EXPORT_SYMBOL_GPL(gpiod_set_raw_array_value);
3148 * gpiod_set_array_value() - assign values to an array of GPIOs
3149 * @array_size: number of elements in the descriptor array / value bitmap
3150 * @desc_array: array of GPIO descriptors whose values will be assigned
3151 * @array_info: information on applicability of fast bitmap processing path
3152 * @value_bitmap: bitmap of values to assign
3154 * Set the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status
3157 * This function can be called from contexts where we cannot sleep, and will
3158 * complain if the GPIO chip functions potentially sleep.
3160 int gpiod_set_array_value(unsigned int array_size,
3161 struct gpio_desc **desc_array,
3162 struct gpio_array *array_info,
3163 unsigned long *value_bitmap)
3167 return gpiod_set_array_value_complex(false, false, array_size,
3168 desc_array, array_info,
3171 EXPORT_SYMBOL_GPL(gpiod_set_array_value);
3174 * gpiod_cansleep() - report whether gpio value access may sleep
3175 * @desc: gpio to check
3178 int gpiod_cansleep(const struct gpio_desc *desc)
3180 VALIDATE_DESC(desc);
3181 return desc->gdev->chip->can_sleep;
3183 EXPORT_SYMBOL_GPL(gpiod_cansleep);
3186 * gpiod_set_consumer_name() - set the consumer name for the descriptor
3187 * @desc: gpio to set the consumer name on
3188 * @name: the new consumer name
3190 int gpiod_set_consumer_name(struct gpio_desc *desc, const char *name)
3192 VALIDATE_DESC(desc);
3194 name = kstrdup_const(name, GFP_KERNEL);
3199 kfree_const(desc->label);
3200 desc_set_label(desc, name);
3204 EXPORT_SYMBOL_GPL(gpiod_set_consumer_name);
3207 * gpiod_to_irq() - return the IRQ corresponding to a GPIO
3208 * @desc: gpio whose IRQ will be returned (already requested)
3210 * Return the IRQ corresponding to the passed GPIO, or an error code in case of
3213 int gpiod_to_irq(const struct gpio_desc *desc)
3215 struct gpio_chip *gc;
3219 * Cannot VALIDATE_DESC() here as gpiod_to_irq() consumer semantics
3220 * requires this function to not return zero on an invalid descriptor
3221 * but rather a negative error number.
3223 if (!desc || IS_ERR(desc) || !desc->gdev || !desc->gdev->chip)
3226 gc = desc->gdev->chip;
3227 offset = gpio_chip_hwgpio(desc);
3229 int retirq = gc->to_irq(gc, offset);
3231 /* Zero means NO_IRQ */
3237 #ifdef CONFIG_GPIOLIB_IRQCHIP
3240 * Avoid race condition with other code, which tries to lookup
3241 * an IRQ before the irqchip has been properly registered,
3242 * i.e. while gpiochip is still being brought up.
3244 return -EPROBE_DEFER;
3249 EXPORT_SYMBOL_GPL(gpiod_to_irq);
3252 * gpiochip_lock_as_irq() - lock a GPIO to be used as IRQ
3253 * @gc: the chip the GPIO to lock belongs to
3254 * @offset: the offset of the GPIO to lock as IRQ
3256 * This is used directly by GPIO drivers that want to lock down
3257 * a certain GPIO line to be used for IRQs.
3259 int gpiochip_lock_as_irq(struct gpio_chip *gc, unsigned int offset)
3261 struct gpio_desc *desc;
3263 desc = gpiochip_get_desc(gc, offset);
3265 return PTR_ERR(desc);
3268 * If it's fast: flush the direction setting if something changed
3271 if (!gc->can_sleep && gc->get_direction) {
3272 int dir = gpiod_get_direction(desc);
3275 chip_err(gc, "%s: cannot get GPIO direction\n",
3281 /* To be valid for IRQ the line needs to be input or open drain */
3282 if (test_bit(FLAG_IS_OUT, &desc->flags) &&
3283 !test_bit(FLAG_OPEN_DRAIN, &desc->flags)) {
3285 "%s: tried to flag a GPIO set as output for IRQ\n",
3290 set_bit(FLAG_USED_AS_IRQ, &desc->flags);
3291 set_bit(FLAG_IRQ_IS_ENABLED, &desc->flags);
3294 * If the consumer has not set up a label (such as when the
3295 * IRQ is referenced from .to_irq()) we set up a label here
3296 * so it is clear this is used as an interrupt.
3299 desc_set_label(desc, "interrupt");
3303 EXPORT_SYMBOL_GPL(gpiochip_lock_as_irq);
3306 * gpiochip_unlock_as_irq() - unlock a GPIO used as IRQ
3307 * @gc: the chip the GPIO to lock belongs to
3308 * @offset: the offset of the GPIO to lock as IRQ
3310 * This is used directly by GPIO drivers that want to indicate
3311 * that a certain GPIO is no longer used exclusively for IRQ.
3313 void gpiochip_unlock_as_irq(struct gpio_chip *gc, unsigned int offset)
3315 struct gpio_desc *desc;
3317 desc = gpiochip_get_desc(gc, offset);
3321 clear_bit(FLAG_USED_AS_IRQ, &desc->flags);
3322 clear_bit(FLAG_IRQ_IS_ENABLED, &desc->flags);
3324 /* If we only had this marking, erase it */
3325 if (desc->label && !strcmp(desc->label, "interrupt"))
3326 desc_set_label(desc, NULL);
3328 EXPORT_SYMBOL_GPL(gpiochip_unlock_as_irq);
3330 void gpiochip_disable_irq(struct gpio_chip *gc, unsigned int offset)
3332 struct gpio_desc *desc = gpiochip_get_desc(gc, offset);
3334 if (!IS_ERR(desc) &&
3335 !WARN_ON(!test_bit(FLAG_USED_AS_IRQ, &desc->flags)))
3336 clear_bit(FLAG_IRQ_IS_ENABLED, &desc->flags);
3338 EXPORT_SYMBOL_GPL(gpiochip_disable_irq);
3340 void gpiochip_enable_irq(struct gpio_chip *gc, unsigned int offset)
3342 struct gpio_desc *desc = gpiochip_get_desc(gc, offset);
3344 if (!IS_ERR(desc) &&
3345 !WARN_ON(!test_bit(FLAG_USED_AS_IRQ, &desc->flags))) {
3347 * We must not be output when using IRQ UNLESS we are
3350 WARN_ON(test_bit(FLAG_IS_OUT, &desc->flags) &&
3351 !test_bit(FLAG_OPEN_DRAIN, &desc->flags));
3352 set_bit(FLAG_IRQ_IS_ENABLED, &desc->flags);
3355 EXPORT_SYMBOL_GPL(gpiochip_enable_irq);
3357 bool gpiochip_line_is_irq(struct gpio_chip *gc, unsigned int offset)
3359 if (offset >= gc->ngpio)
3362 return test_bit(FLAG_USED_AS_IRQ, &gc->gpiodev->descs[offset].flags);
3364 EXPORT_SYMBOL_GPL(gpiochip_line_is_irq);
3366 int gpiochip_reqres_irq(struct gpio_chip *gc, unsigned int offset)
3370 if (!try_module_get(gc->gpiodev->owner))
3373 ret = gpiochip_lock_as_irq(gc, offset);
3375 chip_err(gc, "unable to lock HW IRQ %u for IRQ\n", offset);
3376 module_put(gc->gpiodev->owner);
3381 EXPORT_SYMBOL_GPL(gpiochip_reqres_irq);
3383 void gpiochip_relres_irq(struct gpio_chip *gc, unsigned int offset)
3385 gpiochip_unlock_as_irq(gc, offset);
3386 module_put(gc->gpiodev->owner);
3388 EXPORT_SYMBOL_GPL(gpiochip_relres_irq);
3390 bool gpiochip_line_is_open_drain(struct gpio_chip *gc, unsigned int offset)
3392 if (offset >= gc->ngpio)
3395 return test_bit(FLAG_OPEN_DRAIN, &gc->gpiodev->descs[offset].flags);
3397 EXPORT_SYMBOL_GPL(gpiochip_line_is_open_drain);
3399 bool gpiochip_line_is_open_source(struct gpio_chip *gc, unsigned int offset)
3401 if (offset >= gc->ngpio)
3404 return test_bit(FLAG_OPEN_SOURCE, &gc->gpiodev->descs[offset].flags);
3406 EXPORT_SYMBOL_GPL(gpiochip_line_is_open_source);
3408 bool gpiochip_line_is_persistent(struct gpio_chip *gc, unsigned int offset)
3410 if (offset >= gc->ngpio)
3413 return !test_bit(FLAG_TRANSITORY, &gc->gpiodev->descs[offset].flags);
3415 EXPORT_SYMBOL_GPL(gpiochip_line_is_persistent);
3418 * gpiod_get_raw_value_cansleep() - return a gpio's raw value
3419 * @desc: gpio whose value will be returned
3421 * Return the GPIO's raw value, i.e. the value of the physical line disregarding
3422 * its ACTIVE_LOW status, or negative errno on failure.
3424 * This function is to be called from contexts that can sleep.
3426 int gpiod_get_raw_value_cansleep(const struct gpio_desc *desc)
3428 might_sleep_if(extra_checks);
3429 VALIDATE_DESC(desc);
3430 return gpiod_get_raw_value_commit(desc);
3432 EXPORT_SYMBOL_GPL(gpiod_get_raw_value_cansleep);
3435 * gpiod_get_value_cansleep() - return a gpio's value
3436 * @desc: gpio whose value will be returned
3438 * Return the GPIO's logical value, i.e. taking the ACTIVE_LOW status into
3439 * account, or negative errno on failure.
3441 * This function is to be called from contexts that can sleep.
3443 int gpiod_get_value_cansleep(const struct gpio_desc *desc)
3447 might_sleep_if(extra_checks);
3448 VALIDATE_DESC(desc);
3449 value = gpiod_get_raw_value_commit(desc);
3453 if (test_bit(FLAG_ACTIVE_LOW, &desc->flags))
3458 EXPORT_SYMBOL_GPL(gpiod_get_value_cansleep);
3461 * gpiod_get_raw_array_value_cansleep() - read raw values from an array of GPIOs
3462 * @array_size: number of elements in the descriptor array / value bitmap
3463 * @desc_array: array of GPIO descriptors whose values will be read
3464 * @array_info: information on applicability of fast bitmap processing path
3465 * @value_bitmap: bitmap to store the read values
3467 * Read the raw values of the GPIOs, i.e. the values of the physical lines
3468 * without regard for their ACTIVE_LOW status. Return 0 in case of success,
3469 * else an error code.
3471 * This function is to be called from contexts that can sleep.
3473 int gpiod_get_raw_array_value_cansleep(unsigned int array_size,
3474 struct gpio_desc **desc_array,
3475 struct gpio_array *array_info,
3476 unsigned long *value_bitmap)
3478 might_sleep_if(extra_checks);
3481 return gpiod_get_array_value_complex(true, true, array_size,
3482 desc_array, array_info,
3485 EXPORT_SYMBOL_GPL(gpiod_get_raw_array_value_cansleep);
3488 * gpiod_get_array_value_cansleep() - read values from an array of GPIOs
3489 * @array_size: number of elements in the descriptor array / value bitmap
3490 * @desc_array: array of GPIO descriptors whose values will be read
3491 * @array_info: information on applicability of fast bitmap processing path
3492 * @value_bitmap: bitmap to store the read values
3494 * Read the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status
3495 * into account. Return 0 in case of success, else an error code.
3497 * This function is to be called from contexts that can sleep.
3499 int gpiod_get_array_value_cansleep(unsigned int array_size,
3500 struct gpio_desc **desc_array,
3501 struct gpio_array *array_info,
3502 unsigned long *value_bitmap)
3504 might_sleep_if(extra_checks);
3507 return gpiod_get_array_value_complex(false, true, array_size,
3508 desc_array, array_info,
3511 EXPORT_SYMBOL_GPL(gpiod_get_array_value_cansleep);
3514 * gpiod_set_raw_value_cansleep() - assign a gpio's raw value
3515 * @desc: gpio whose value will be assigned
3516 * @value: value to assign
3518 * Set the raw value of the GPIO, i.e. the value of its physical line without
3519 * regard for its ACTIVE_LOW status.
3521 * This function is to be called from contexts that can sleep.
3523 void gpiod_set_raw_value_cansleep(struct gpio_desc *desc, int value)
3525 might_sleep_if(extra_checks);
3526 VALIDATE_DESC_VOID(desc);
3527 gpiod_set_raw_value_commit(desc, value);
3529 EXPORT_SYMBOL_GPL(gpiod_set_raw_value_cansleep);
3532 * gpiod_set_value_cansleep() - assign a gpio's value
3533 * @desc: gpio whose value will be assigned
3534 * @value: value to assign
3536 * Set the logical value of the GPIO, i.e. taking its ACTIVE_LOW status into
3539 * This function is to be called from contexts that can sleep.
3541 void gpiod_set_value_cansleep(struct gpio_desc *desc, int value)
3543 might_sleep_if(extra_checks);
3544 VALIDATE_DESC_VOID(desc);
3545 gpiod_set_value_nocheck(desc, value);
3547 EXPORT_SYMBOL_GPL(gpiod_set_value_cansleep);
3550 * gpiod_set_raw_array_value_cansleep() - assign values to an array of GPIOs
3551 * @array_size: number of elements in the descriptor array / value bitmap
3552 * @desc_array: array of GPIO descriptors whose values will be assigned
3553 * @array_info: information on applicability of fast bitmap processing path
3554 * @value_bitmap: bitmap of values to assign
3556 * Set the raw values of the GPIOs, i.e. the values of the physical lines
3557 * without regard for their ACTIVE_LOW status.
3559 * This function is to be called from contexts that can sleep.
3561 int gpiod_set_raw_array_value_cansleep(unsigned int array_size,
3562 struct gpio_desc **desc_array,
3563 struct gpio_array *array_info,
3564 unsigned long *value_bitmap)
3566 might_sleep_if(extra_checks);
3569 return gpiod_set_array_value_complex(true, true, array_size, desc_array,
3570 array_info, value_bitmap);
3572 EXPORT_SYMBOL_GPL(gpiod_set_raw_array_value_cansleep);
3575 * gpiod_add_lookup_tables() - register GPIO device consumers
3576 * @tables: list of tables of consumers to register
3577 * @n: number of tables in the list
3579 void gpiod_add_lookup_tables(struct gpiod_lookup_table **tables, size_t n)
3583 mutex_lock(&gpio_lookup_lock);
3585 for (i = 0; i < n; i++)
3586 list_add_tail(&tables[i]->list, &gpio_lookup_list);
3588 mutex_unlock(&gpio_lookup_lock);
3592 * gpiod_set_array_value_cansleep() - assign values to an array of GPIOs
3593 * @array_size: number of elements in the descriptor array / value bitmap
3594 * @desc_array: array of GPIO descriptors whose values will be assigned
3595 * @array_info: information on applicability of fast bitmap processing path
3596 * @value_bitmap: bitmap of values to assign
3598 * Set the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status
3601 * This function is to be called from contexts that can sleep.
3603 int gpiod_set_array_value_cansleep(unsigned int array_size,
3604 struct gpio_desc **desc_array,
3605 struct gpio_array *array_info,
3606 unsigned long *value_bitmap)
3608 might_sleep_if(extra_checks);
3611 return gpiod_set_array_value_complex(false, true, array_size,
3612 desc_array, array_info,
3615 EXPORT_SYMBOL_GPL(gpiod_set_array_value_cansleep);
3618 * gpiod_add_lookup_table() - register GPIO device consumers
3619 * @table: table of consumers to register
3621 void gpiod_add_lookup_table(struct gpiod_lookup_table *table)
3623 mutex_lock(&gpio_lookup_lock);
3625 list_add_tail(&table->list, &gpio_lookup_list);
3627 mutex_unlock(&gpio_lookup_lock);
3629 EXPORT_SYMBOL_GPL(gpiod_add_lookup_table);
3632 * gpiod_remove_lookup_table() - unregister GPIO device consumers
3633 * @table: table of consumers to unregister
3635 void gpiod_remove_lookup_table(struct gpiod_lookup_table *table)
3637 mutex_lock(&gpio_lookup_lock);
3639 list_del(&table->list);
3641 mutex_unlock(&gpio_lookup_lock);
3643 EXPORT_SYMBOL_GPL(gpiod_remove_lookup_table);
3646 * gpiod_add_hogs() - register a set of GPIO hogs from machine code
3647 * @hogs: table of gpio hog entries with a zeroed sentinel at the end
3649 void gpiod_add_hogs(struct gpiod_hog *hogs)
3651 struct gpio_chip *gc;
3652 struct gpiod_hog *hog;
3654 mutex_lock(&gpio_machine_hogs_mutex);
3656 for (hog = &hogs[0]; hog->chip_label; hog++) {
3657 list_add_tail(&hog->list, &gpio_machine_hogs);
3660 * The chip may have been registered earlier, so check if it
3661 * exists and, if so, try to hog the line now.
3663 gc = find_chip_by_name(hog->chip_label);
3665 gpiochip_machine_hog(gc, hog);
3668 mutex_unlock(&gpio_machine_hogs_mutex);
3670 EXPORT_SYMBOL_GPL(gpiod_add_hogs);
3672 static struct gpiod_lookup_table *gpiod_find_lookup_table(struct device *dev)
3674 const char *dev_id = dev ? dev_name(dev) : NULL;
3675 struct gpiod_lookup_table *table;
3677 mutex_lock(&gpio_lookup_lock);
3679 list_for_each_entry(table, &gpio_lookup_list, list) {
3680 if (table->dev_id && dev_id) {
3682 * Valid strings on both ends, must be identical to have
3685 if (!strcmp(table->dev_id, dev_id))
3689 * One of the pointers is NULL, so both must be to have
3692 if (dev_id == table->dev_id)
3699 mutex_unlock(&gpio_lookup_lock);
3703 static struct gpio_desc *gpiod_find(struct device *dev, const char *con_id,
3704 unsigned int idx, unsigned long *flags)
3706 struct gpio_desc *desc = ERR_PTR(-ENOENT);
3707 struct gpiod_lookup_table *table;
3708 struct gpiod_lookup *p;
3710 table = gpiod_find_lookup_table(dev);
3714 for (p = &table->table[0]; p->key; p++) {
3715 struct gpio_chip *gc;
3717 /* idx must always match exactly */
3721 /* If the lookup entry has a con_id, require exact match */
3722 if (p->con_id && (!con_id || strcmp(p->con_id, con_id)))
3725 if (p->chip_hwnum == U16_MAX) {
3726 desc = gpio_name_to_desc(p->key);
3732 dev_warn(dev, "cannot find GPIO line %s, deferring\n",
3734 return ERR_PTR(-EPROBE_DEFER);
3737 gc = find_chip_by_name(p->key);
3741 * As the lookup table indicates a chip with
3742 * p->key should exist, assume it may
3743 * still appear later and let the interested
3744 * consumer be probed again or let the Deferred
3745 * Probe infrastructure handle the error.
3747 dev_warn(dev, "cannot find GPIO chip %s, deferring\n",
3749 return ERR_PTR(-EPROBE_DEFER);
3752 if (gc->ngpio <= p->chip_hwnum) {
3754 "requested GPIO %u (%u) is out of range [0..%u] for chip %s\n",
3755 idx, p->chip_hwnum, gc->ngpio - 1,
3757 return ERR_PTR(-EINVAL);
3760 desc = gpiochip_get_desc(gc, p->chip_hwnum);
3769 static int platform_gpio_count(struct device *dev, const char *con_id)
3771 struct gpiod_lookup_table *table;
3772 struct gpiod_lookup *p;
3773 unsigned int count = 0;
3775 table = gpiod_find_lookup_table(dev);
3779 for (p = &table->table[0]; p->key; p++) {
3780 if ((con_id && p->con_id && !strcmp(con_id, p->con_id)) ||
3781 (!con_id && !p->con_id))
3791 * fwnode_gpiod_get_index - obtain a GPIO from firmware node
3792 * @fwnode: handle of the firmware node
3793 * @con_id: function within the GPIO consumer
3794 * @index: index of the GPIO to obtain for the consumer
3795 * @flags: GPIO initialization flags
3796 * @label: label to attach to the requested GPIO
3798 * This function can be used for drivers that get their configuration
3799 * from opaque firmware.
3801 * The function properly finds the corresponding GPIO using whatever is the
3802 * underlying firmware interface and then makes sure that the GPIO
3803 * descriptor is requested before it is returned to the caller.
3806 * On successful request the GPIO pin is configured in accordance with
3809 * In case of error an ERR_PTR() is returned.
3811 struct gpio_desc *fwnode_gpiod_get_index(struct fwnode_handle *fwnode,
3812 const char *con_id, int index,
3813 enum gpiod_flags flags,
3816 struct gpio_desc *desc;
3817 char prop_name[32]; /* 32 is max size of property name */
3820 for (i = 0; i < ARRAY_SIZE(gpio_suffixes); i++) {
3822 snprintf(prop_name, sizeof(prop_name), "%s-%s",
3823 con_id, gpio_suffixes[i]);
3825 snprintf(prop_name, sizeof(prop_name), "%s",
3828 desc = fwnode_get_named_gpiod(fwnode, prop_name, index, flags,
3830 if (!IS_ERR(desc) || (PTR_ERR(desc) != -ENOENT))
3836 EXPORT_SYMBOL_GPL(fwnode_gpiod_get_index);
3839 * gpiod_count - return the number of GPIOs associated with a device / function
3840 * or -ENOENT if no GPIO has been assigned to the requested function
3841 * @dev: GPIO consumer, can be NULL for system-global GPIOs
3842 * @con_id: function within the GPIO consumer
3844 int gpiod_count(struct device *dev, const char *con_id)
3846 int count = -ENOENT;
3848 if (IS_ENABLED(CONFIG_OF) && dev && dev->of_node)
3849 count = of_gpio_get_count(dev, con_id);
3850 else if (IS_ENABLED(CONFIG_ACPI) && dev && ACPI_HANDLE(dev))
3851 count = acpi_gpio_count(dev, con_id);
3854 count = platform_gpio_count(dev, con_id);
3858 EXPORT_SYMBOL_GPL(gpiod_count);
3861 * gpiod_get - obtain a GPIO for a given GPIO function
3862 * @dev: GPIO consumer, can be NULL for system-global GPIOs
3863 * @con_id: function within the GPIO consumer
3864 * @flags: optional GPIO initialization flags
3866 * Return the GPIO descriptor corresponding to the function con_id of device
3867 * dev, -ENOENT if no GPIO has been assigned to the requested function, or
3868 * another IS_ERR() code if an error occurred while trying to acquire the GPIO.
3870 struct gpio_desc *__must_check gpiod_get(struct device *dev, const char *con_id,
3871 enum gpiod_flags flags)
3873 return gpiod_get_index(dev, con_id, 0, flags);
3875 EXPORT_SYMBOL_GPL(gpiod_get);
3878 * gpiod_get_optional - obtain an optional GPIO for a given GPIO function
3879 * @dev: GPIO consumer, can be NULL for system-global GPIOs
3880 * @con_id: function within the GPIO consumer
3881 * @flags: optional GPIO initialization flags
3883 * This is equivalent to gpiod_get(), except that when no GPIO was assigned to
3884 * the requested function it will return NULL. This is convenient for drivers
3885 * that need to handle optional GPIOs.
3887 struct gpio_desc *__must_check gpiod_get_optional(struct device *dev,
3889 enum gpiod_flags flags)
3891 return gpiod_get_index_optional(dev, con_id, 0, flags);
3893 EXPORT_SYMBOL_GPL(gpiod_get_optional);
3897 * gpiod_configure_flags - helper function to configure a given GPIO
3898 * @desc: gpio whose value will be assigned
3899 * @con_id: function within the GPIO consumer
3900 * @lflags: bitmask of gpio_lookup_flags GPIO_* values - returned from
3901 * of_find_gpio() or of_get_gpio_hog()
3902 * @dflags: gpiod_flags - optional GPIO initialization flags
3904 * Return 0 on success, -ENOENT if no GPIO has been assigned to the
3905 * requested function and/or index, or another IS_ERR() code if an error
3906 * occurred while trying to acquire the GPIO.
3908 int gpiod_configure_flags(struct gpio_desc *desc, const char *con_id,
3909 unsigned long lflags, enum gpiod_flags dflags)
3913 if (lflags & GPIO_ACTIVE_LOW)
3914 set_bit(FLAG_ACTIVE_LOW, &desc->flags);
3916 if (lflags & GPIO_OPEN_DRAIN)
3917 set_bit(FLAG_OPEN_DRAIN, &desc->flags);
3918 else if (dflags & GPIOD_FLAGS_BIT_OPEN_DRAIN) {
3920 * This enforces open drain mode from the consumer side.
3921 * This is necessary for some busses like I2C, but the lookup
3922 * should *REALLY* have specified them as open drain in the
3923 * first place, so print a little warning here.
3925 set_bit(FLAG_OPEN_DRAIN, &desc->flags);
3927 "enforced open drain please flag it properly in DT/ACPI DSDT/board file\n");
3930 if (lflags & GPIO_OPEN_SOURCE)
3931 set_bit(FLAG_OPEN_SOURCE, &desc->flags);
3933 if ((lflags & GPIO_PULL_UP) && (lflags & GPIO_PULL_DOWN)) {
3935 "both pull-up and pull-down enabled, invalid configuration\n");
3939 if (lflags & GPIO_PULL_UP)
3940 set_bit(FLAG_PULL_UP, &desc->flags);
3941 else if (lflags & GPIO_PULL_DOWN)
3942 set_bit(FLAG_PULL_DOWN, &desc->flags);
3944 ret = gpiod_set_transitory(desc, (lflags & GPIO_TRANSITORY));
3948 /* No particular flag request, return here... */
3949 if (!(dflags & GPIOD_FLAGS_BIT_DIR_SET)) {
3950 gpiod_dbg(desc, "no flags found for %s\n", con_id);
3955 if (dflags & GPIOD_FLAGS_BIT_DIR_OUT)
3956 ret = gpiod_direction_output(desc,
3957 !!(dflags & GPIOD_FLAGS_BIT_DIR_VAL));
3959 ret = gpiod_direction_input(desc);
3965 * gpiod_get_index - obtain a GPIO from a multi-index GPIO function
3966 * @dev: GPIO consumer, can be NULL for system-global GPIOs
3967 * @con_id: function within the GPIO consumer
3968 * @idx: index of the GPIO to obtain in the consumer
3969 * @flags: optional GPIO initialization flags
3971 * This variant of gpiod_get() allows to access GPIOs other than the first
3972 * defined one for functions that define several GPIOs.
3974 * Return a valid GPIO descriptor, -ENOENT if no GPIO has been assigned to the
3975 * requested function and/or index, or another IS_ERR() code if an error
3976 * occurred while trying to acquire the GPIO.
3978 struct gpio_desc *__must_check gpiod_get_index(struct device *dev,
3981 enum gpiod_flags flags)
3983 unsigned long lookupflags = GPIO_LOOKUP_FLAGS_DEFAULT;
3984 struct gpio_desc *desc = NULL;
3986 /* Maybe we have a device name, maybe not */
3987 const char *devname = dev ? dev_name(dev) : "?";
3989 dev_dbg(dev, "GPIO lookup for consumer %s\n", con_id);
3992 /* Using device tree? */
3993 if (IS_ENABLED(CONFIG_OF) && dev->of_node) {
3994 dev_dbg(dev, "using device tree for GPIO lookup\n");
3995 desc = of_find_gpio(dev, con_id, idx, &lookupflags);
3996 } else if (ACPI_COMPANION(dev)) {
3997 dev_dbg(dev, "using ACPI for GPIO lookup\n");
3998 desc = acpi_find_gpio(dev, con_id, idx, &flags, &lookupflags);
4003 * Either we are not using DT or ACPI, or their lookup did not return
4004 * a result. In that case, use platform lookup as a fallback.
4006 if (!desc || desc == ERR_PTR(-ENOENT)) {
4007 dev_dbg(dev, "using lookup tables for GPIO lookup\n");
4008 desc = gpiod_find(dev, con_id, idx, &lookupflags);
4012 dev_dbg(dev, "No GPIO consumer %s found\n", con_id);
4017 * If a connection label was passed use that, else attempt to use
4018 * the device name as label
4020 ret = gpiod_request(desc, con_id ? con_id : devname);
4022 if (ret == -EBUSY && flags & GPIOD_FLAGS_BIT_NONEXCLUSIVE) {
4024 * This happens when there are several consumers for
4025 * the same GPIO line: we just return here without
4026 * further initialization. It is a bit if a hack.
4027 * This is necessary to support fixed regulators.
4029 * FIXME: Make this more sane and safe.
4031 dev_info(dev, "nonexclusive access to GPIO for %s\n",
4032 con_id ? con_id : devname);
4035 return ERR_PTR(ret);
4039 ret = gpiod_configure_flags(desc, con_id, lookupflags, flags);
4041 dev_dbg(dev, "setup of GPIO %s failed\n", con_id);
4043 return ERR_PTR(ret);
4046 blocking_notifier_call_chain(&desc->gdev->notifier,
4047 GPIOLINE_CHANGED_REQUESTED, desc);
4051 EXPORT_SYMBOL_GPL(gpiod_get_index);
4054 * fwnode_get_named_gpiod - obtain a GPIO from firmware node
4055 * @fwnode: handle of the firmware node
4056 * @propname: name of the firmware property representing the GPIO
4057 * @index: index of the GPIO to obtain for the consumer
4058 * @dflags: GPIO initialization flags
4059 * @label: label to attach to the requested GPIO
4061 * This function can be used for drivers that get their configuration
4062 * from opaque firmware.
4064 * The function properly finds the corresponding GPIO using whatever is the
4065 * underlying firmware interface and then makes sure that the GPIO
4066 * descriptor is requested before it is returned to the caller.
4069 * On successful request the GPIO pin is configured in accordance with
4072 * In case of error an ERR_PTR() is returned.
4074 struct gpio_desc *fwnode_get_named_gpiod(struct fwnode_handle *fwnode,
4075 const char *propname, int index,
4076 enum gpiod_flags dflags,
4079 unsigned long lflags = GPIO_LOOKUP_FLAGS_DEFAULT;
4080 struct gpio_desc *desc = ERR_PTR(-ENODEV);
4084 return ERR_PTR(-EINVAL);
4086 if (is_of_node(fwnode)) {
4087 desc = gpiod_get_from_of_node(to_of_node(fwnode),
4092 } else if (is_acpi_node(fwnode)) {
4093 struct acpi_gpio_info info;
4095 desc = acpi_node_get_gpiod(fwnode, propname, index, &info);
4099 acpi_gpio_update_gpiod_flags(&dflags, &info);
4100 acpi_gpio_update_gpiod_lookup_flags(&lflags, &info);
4103 /* Currently only ACPI takes this path */
4104 ret = gpiod_request(desc, label);
4106 return ERR_PTR(ret);
4108 ret = gpiod_configure_flags(desc, propname, lflags, dflags);
4111 return ERR_PTR(ret);
4114 blocking_notifier_call_chain(&desc->gdev->notifier,
4115 GPIOLINE_CHANGED_REQUESTED, desc);
4119 EXPORT_SYMBOL_GPL(fwnode_get_named_gpiod);
4122 * gpiod_get_index_optional - obtain an optional GPIO from a multi-index GPIO
4124 * @dev: GPIO consumer, can be NULL for system-global GPIOs
4125 * @con_id: function within the GPIO consumer
4126 * @index: index of the GPIO to obtain in the consumer
4127 * @flags: optional GPIO initialization flags
4129 * This is equivalent to gpiod_get_index(), except that when no GPIO with the
4130 * specified index was assigned to the requested function it will return NULL.
4131 * This is convenient for drivers that need to handle optional GPIOs.
4133 struct gpio_desc *__must_check gpiod_get_index_optional(struct device *dev,
4136 enum gpiod_flags flags)
4138 struct gpio_desc *desc;
4140 desc = gpiod_get_index(dev, con_id, index, flags);
4142 if (PTR_ERR(desc) == -ENOENT)
4148 EXPORT_SYMBOL_GPL(gpiod_get_index_optional);
4151 * gpiod_hog - Hog the specified GPIO desc given the provided flags
4152 * @desc: gpio whose value will be assigned
4153 * @name: gpio line name
4154 * @lflags: bitmask of gpio_lookup_flags GPIO_* values - returned from
4155 * of_find_gpio() or of_get_gpio_hog()
4156 * @dflags: gpiod_flags - optional GPIO initialization flags
4158 int gpiod_hog(struct gpio_desc *desc, const char *name,
4159 unsigned long lflags, enum gpiod_flags dflags)
4161 struct gpio_chip *gc;
4162 struct gpio_desc *local_desc;
4166 gc = gpiod_to_chip(desc);
4167 hwnum = gpio_chip_hwgpio(desc);
4169 local_desc = gpiochip_request_own_desc(gc, hwnum, name,
4171 if (IS_ERR(local_desc)) {
4172 ret = PTR_ERR(local_desc);
4173 pr_err("requesting hog GPIO %s (chip %s, offset %d) failed, %d\n",
4174 name, gc->label, hwnum, ret);
4178 /* Mark GPIO as hogged so it can be identified and removed later */
4179 set_bit(FLAG_IS_HOGGED, &desc->flags);
4181 gpiod_info(desc, "hogged as %s%s\n",
4182 (dflags & GPIOD_FLAGS_BIT_DIR_OUT) ? "output" : "input",
4183 (dflags & GPIOD_FLAGS_BIT_DIR_OUT) ?
4184 (dflags & GPIOD_FLAGS_BIT_DIR_VAL) ? "/high" : "/low" : "");
4190 * gpiochip_free_hogs - Scan gpio-controller chip and release GPIO hog
4191 * @gc: gpio chip to act on
4193 static void gpiochip_free_hogs(struct gpio_chip *gc)
4197 for (id = 0; id < gc->ngpio; id++) {
4198 if (test_bit(FLAG_IS_HOGGED, &gc->gpiodev->descs[id].flags))
4199 gpiochip_free_own_desc(&gc->gpiodev->descs[id]);
4204 * gpiod_get_array - obtain multiple GPIOs from a multi-index GPIO function
4205 * @dev: GPIO consumer, can be NULL for system-global GPIOs
4206 * @con_id: function within the GPIO consumer
4207 * @flags: optional GPIO initialization flags
4209 * This function acquires all the GPIOs defined under a given function.
4211 * Return a struct gpio_descs containing an array of descriptors, -ENOENT if
4212 * no GPIO has been assigned to the requested function, or another IS_ERR()
4213 * code if an error occurred while trying to acquire the GPIOs.
4215 struct gpio_descs *__must_check gpiod_get_array(struct device *dev,
4217 enum gpiod_flags flags)
4219 struct gpio_desc *desc;
4220 struct gpio_descs *descs;
4221 struct gpio_array *array_info = NULL;
4222 struct gpio_chip *gc;
4223 int count, bitmap_size;
4225 count = gpiod_count(dev, con_id);
4227 return ERR_PTR(count);
4229 descs = kzalloc(struct_size(descs, desc, count), GFP_KERNEL);
4231 return ERR_PTR(-ENOMEM);
4233 for (descs->ndescs = 0; descs->ndescs < count; ) {
4234 desc = gpiod_get_index(dev, con_id, descs->ndescs, flags);
4236 gpiod_put_array(descs);
4237 return ERR_CAST(desc);
4240 descs->desc[descs->ndescs] = desc;
4242 gc = gpiod_to_chip(desc);
4244 * If pin hardware number of array member 0 is also 0, select
4245 * its chip as a candidate for fast bitmap processing path.
4247 if (descs->ndescs == 0 && gpio_chip_hwgpio(desc) == 0) {
4248 struct gpio_descs *array;
4250 bitmap_size = BITS_TO_LONGS(gc->ngpio > count ?
4253 array = kzalloc(struct_size(descs, desc, count) +
4254 struct_size(array_info, invert_mask,
4255 3 * bitmap_size), GFP_KERNEL);
4257 gpiod_put_array(descs);
4258 return ERR_PTR(-ENOMEM);
4261 memcpy(array, descs,
4262 struct_size(descs, desc, descs->ndescs + 1));
4266 array_info = (void *)(descs->desc + count);
4267 array_info->get_mask = array_info->invert_mask +
4269 array_info->set_mask = array_info->get_mask +
4272 array_info->desc = descs->desc;
4273 array_info->size = count;
4274 array_info->chip = gc;
4275 bitmap_set(array_info->get_mask, descs->ndescs,
4276 count - descs->ndescs);
4277 bitmap_set(array_info->set_mask, descs->ndescs,
4278 count - descs->ndescs);
4279 descs->info = array_info;
4281 /* Unmark array members which don't belong to the 'fast' chip */
4282 if (array_info && array_info->chip != gc) {
4283 __clear_bit(descs->ndescs, array_info->get_mask);
4284 __clear_bit(descs->ndescs, array_info->set_mask);
4287 * Detect array members which belong to the 'fast' chip
4288 * but their pins are not in hardware order.
4290 else if (array_info &&
4291 gpio_chip_hwgpio(desc) != descs->ndescs) {
4293 * Don't use fast path if all array members processed so
4294 * far belong to the same chip as this one but its pin
4295 * hardware number is different from its array index.
4297 if (bitmap_full(array_info->get_mask, descs->ndescs)) {
4300 __clear_bit(descs->ndescs,
4301 array_info->get_mask);
4302 __clear_bit(descs->ndescs,
4303 array_info->set_mask);
4305 } else if (array_info) {
4306 /* Exclude open drain or open source from fast output */
4307 if (gpiochip_line_is_open_drain(gc, descs->ndescs) ||
4308 gpiochip_line_is_open_source(gc, descs->ndescs))
4309 __clear_bit(descs->ndescs,
4310 array_info->set_mask);
4311 /* Identify 'fast' pins which require invertion */
4312 if (gpiod_is_active_low(desc))
4313 __set_bit(descs->ndescs,
4314 array_info->invert_mask);
4321 "GPIO array info: chip=%s, size=%d, get_mask=%lx, set_mask=%lx, invert_mask=%lx\n",
4322 array_info->chip->label, array_info->size,
4323 *array_info->get_mask, *array_info->set_mask,
4324 *array_info->invert_mask);
4327 EXPORT_SYMBOL_GPL(gpiod_get_array);
4330 * gpiod_get_array_optional - obtain multiple GPIOs from a multi-index GPIO
4332 * @dev: GPIO consumer, can be NULL for system-global GPIOs
4333 * @con_id: function within the GPIO consumer
4334 * @flags: optional GPIO initialization flags
4336 * This is equivalent to gpiod_get_array(), except that when no GPIO was
4337 * assigned to the requested function it will return NULL.
4339 struct gpio_descs *__must_check gpiod_get_array_optional(struct device *dev,
4341 enum gpiod_flags flags)
4343 struct gpio_descs *descs;
4345 descs = gpiod_get_array(dev, con_id, flags);
4346 if (PTR_ERR(descs) == -ENOENT)
4351 EXPORT_SYMBOL_GPL(gpiod_get_array_optional);
4354 * gpiod_put - dispose of a GPIO descriptor
4355 * @desc: GPIO descriptor to dispose of
4357 * No descriptor can be used after gpiod_put() has been called on it.
4359 void gpiod_put(struct gpio_desc *desc)
4364 EXPORT_SYMBOL_GPL(gpiod_put);
4367 * gpiod_put_array - dispose of multiple GPIO descriptors
4368 * @descs: struct gpio_descs containing an array of descriptors
4370 void gpiod_put_array(struct gpio_descs *descs)
4374 for (i = 0; i < descs->ndescs; i++)
4375 gpiod_put(descs->desc[i]);
4379 EXPORT_SYMBOL_GPL(gpiod_put_array);
4381 static int __init gpiolib_dev_init(void)
4385 /* Register GPIO sysfs bus */
4386 ret = bus_register(&gpio_bus_type);
4388 pr_err("gpiolib: could not register GPIO bus type\n");
4392 ret = alloc_chrdev_region(&gpio_devt, 0, GPIO_DEV_MAX, GPIOCHIP_NAME);
4394 pr_err("gpiolib: failed to allocate char dev region\n");
4395 bus_unregister(&gpio_bus_type);
4399 gpiolib_initialized = true;
4400 gpiochip_setup_devs();
4402 #if IS_ENABLED(CONFIG_OF_DYNAMIC) && IS_ENABLED(CONFIG_OF_GPIO)
4403 WARN_ON(of_reconfig_notifier_register(&gpio_of_notifier));
4404 #endif /* CONFIG_OF_DYNAMIC && CONFIG_OF_GPIO */
4408 core_initcall(gpiolib_dev_init);
4410 #ifdef CONFIG_DEBUG_FS
4412 static void gpiolib_dbg_show(struct seq_file *s, struct gpio_device *gdev)
4415 struct gpio_chip *gc = gdev->chip;
4416 unsigned gpio = gdev->base;
4417 struct gpio_desc *gdesc = &gdev->descs[0];
4422 for (i = 0; i < gdev->ngpio; i++, gpio++, gdesc++) {
4423 if (!test_bit(FLAG_REQUESTED, &gdesc->flags)) {
4425 seq_printf(s, " gpio-%-3d (%-20.20s)\n",
4431 gpiod_get_direction(gdesc);
4432 is_out = test_bit(FLAG_IS_OUT, &gdesc->flags);
4433 is_irq = test_bit(FLAG_USED_AS_IRQ, &gdesc->flags);
4434 active_low = test_bit(FLAG_ACTIVE_LOW, &gdesc->flags);
4435 seq_printf(s, " gpio-%-3d (%-20.20s|%-20.20s) %s %s %s%s",
4436 gpio, gdesc->name ? gdesc->name : "", gdesc->label,
4437 is_out ? "out" : "in ",
4438 gc->get ? (gc->get(gc, i) ? "hi" : "lo") : "? ",
4439 is_irq ? "IRQ " : "",
4440 active_low ? "ACTIVE LOW" : "");
4441 seq_printf(s, "\n");
4445 static void *gpiolib_seq_start(struct seq_file *s, loff_t *pos)
4447 unsigned long flags;
4448 struct gpio_device *gdev = NULL;
4449 loff_t index = *pos;
4453 spin_lock_irqsave(&gpio_lock, flags);
4454 list_for_each_entry(gdev, &gpio_devices, list)
4456 spin_unlock_irqrestore(&gpio_lock, flags);
4459 spin_unlock_irqrestore(&gpio_lock, flags);
4464 static void *gpiolib_seq_next(struct seq_file *s, void *v, loff_t *pos)
4466 unsigned long flags;
4467 struct gpio_device *gdev = v;
4470 spin_lock_irqsave(&gpio_lock, flags);
4471 if (list_is_last(&gdev->list, &gpio_devices))
4474 ret = list_entry(gdev->list.next, struct gpio_device, list);
4475 spin_unlock_irqrestore(&gpio_lock, flags);
4483 static void gpiolib_seq_stop(struct seq_file *s, void *v)
4487 static int gpiolib_seq_show(struct seq_file *s, void *v)
4489 struct gpio_device *gdev = v;
4490 struct gpio_chip *gc = gdev->chip;
4491 struct device *parent;
4494 seq_printf(s, "%s%s: (dangling chip)", (char *)s->private,
4495 dev_name(&gdev->dev));
4499 seq_printf(s, "%s%s: GPIOs %d-%d", (char *)s->private,
4500 dev_name(&gdev->dev),
4501 gdev->base, gdev->base + gdev->ngpio - 1);
4502 parent = gc->parent;
4504 seq_printf(s, ", parent: %s/%s",
4505 parent->bus ? parent->bus->name : "no-bus",
4508 seq_printf(s, ", %s", gc->label);
4510 seq_printf(s, ", can sleep");
4511 seq_printf(s, ":\n");
4514 gc->dbg_show(s, gc);
4516 gpiolib_dbg_show(s, gdev);
4521 static const struct seq_operations gpiolib_sops = {
4522 .start = gpiolib_seq_start,
4523 .next = gpiolib_seq_next,
4524 .stop = gpiolib_seq_stop,
4525 .show = gpiolib_seq_show,
4527 DEFINE_SEQ_ATTRIBUTE(gpiolib);
4529 static int __init gpiolib_debugfs_init(void)
4531 /* /sys/kernel/debug/gpio */
4532 debugfs_create_file("gpio", 0444, NULL, NULL, &gpiolib_fops);
4535 subsys_initcall(gpiolib_debugfs_init);
4537 #endif /* DEBUG_FS */