1 // SPDX-License-Identifier: GPL-2.0
3 #include <linux/bitmap.h>
4 #include <linux/kernel.h>
5 #include <linux/module.h>
6 #include <linux/interrupt.h>
8 #include <linux/spinlock.h>
9 #include <linux/list.h>
10 #include <linux/device.h>
11 #include <linux/err.h>
12 #include <linux/debugfs.h>
13 #include <linux/seq_file.h>
14 #include <linux/gpio.h>
15 #include <linux/idr.h>
16 #include <linux/slab.h>
17 #include <linux/acpi.h>
18 #include <linux/gpio/driver.h>
19 #include <linux/gpio/machine.h>
20 #include <linux/pinctrl/consumer.h>
22 #include <linux/compat.h>
23 #include <linux/file.h>
24 #include <uapi/linux/gpio.h>
27 #include "gpiolib-of.h"
28 #include "gpiolib-acpi.h"
29 #include "gpiolib-cdev.h"
30 #include "gpiolib-sysfs.h"
32 #define CREATE_TRACE_POINTS
33 #include <trace/events/gpio.h>
35 /* Implementation infrastructure for GPIO interfaces.
37 * The GPIO programming interface allows for inlining speed-critical
38 * get/set operations for common cases, so that access to SOC-integrated
39 * GPIOs can sometimes cost only an instruction or two per bit.
43 /* When debugging, extend minimal trust to callers and platform code.
44 * Also emit diagnostic messages that may help initial bringup, when
45 * board setup or driver bugs are most common.
47 * Otherwise, minimize overhead in what may be bitbanging codepaths.
50 #define extra_checks 1
52 #define extra_checks 0
55 /* Device and char device-related information */
56 static DEFINE_IDA(gpio_ida);
57 static dev_t gpio_devt;
58 #define GPIO_DEV_MAX 256 /* 256 GPIO chip devices supported */
59 static int gpio_bus_match(struct device *dev, struct device_driver *drv);
60 static struct bus_type gpio_bus_type = {
62 .match = gpio_bus_match,
66 * Number of GPIOs to use for the fast path in set array
68 #define FASTPATH_NGPIO CONFIG_GPIOLIB_FASTPATH_LIMIT
70 /* gpio_lock prevents conflicts during gpio_desc[] table updates.
71 * While any GPIO is requested, its gpio_chip is not removable;
72 * each GPIO's "requested" flag serves as a lock and refcount.
74 DEFINE_SPINLOCK(gpio_lock);
76 static DEFINE_MUTEX(gpio_lookup_lock);
77 static LIST_HEAD(gpio_lookup_list);
78 LIST_HEAD(gpio_devices);
80 static DEFINE_MUTEX(gpio_machine_hogs_mutex);
81 static LIST_HEAD(gpio_machine_hogs);
83 static void gpiochip_free_hogs(struct gpio_chip *gc);
84 static int gpiochip_add_irqchip(struct gpio_chip *gc,
85 struct lock_class_key *lock_key,
86 struct lock_class_key *request_key);
87 static void gpiochip_irqchip_remove(struct gpio_chip *gc);
88 static int gpiochip_irqchip_init_hw(struct gpio_chip *gc);
89 static int gpiochip_irqchip_init_valid_mask(struct gpio_chip *gc);
90 static void gpiochip_irqchip_free_valid_mask(struct gpio_chip *gc);
92 static bool gpiolib_initialized;
94 static inline void desc_set_label(struct gpio_desc *d, const char *label)
100 * gpio_to_desc - Convert a GPIO number to its descriptor
101 * @gpio: global GPIO number
104 * The GPIO descriptor associated with the given GPIO, or %NULL if no GPIO
105 * with the given number exists in the system.
107 struct gpio_desc *gpio_to_desc(unsigned gpio)
109 struct gpio_device *gdev;
112 spin_lock_irqsave(&gpio_lock, flags);
114 list_for_each_entry(gdev, &gpio_devices, list) {
115 if (gdev->base <= gpio &&
116 gdev->base + gdev->ngpio > gpio) {
117 spin_unlock_irqrestore(&gpio_lock, flags);
118 return &gdev->descs[gpio - gdev->base];
122 spin_unlock_irqrestore(&gpio_lock, flags);
124 if (!gpio_is_valid(gpio))
125 pr_warn("invalid GPIO %d\n", gpio);
129 EXPORT_SYMBOL_GPL(gpio_to_desc);
132 * gpiochip_get_desc - get the GPIO descriptor corresponding to the given
133 * hardware number for this chip
135 * @hwnum: hardware number of the GPIO for this chip
138 * A pointer to the GPIO descriptor or ``ERR_PTR(-EINVAL)`` if no GPIO exists
139 * in the given chip for the specified hardware number.
141 struct gpio_desc *gpiochip_get_desc(struct gpio_chip *gc,
144 struct gpio_device *gdev = gc->gpiodev;
146 if (hwnum >= gdev->ngpio)
147 return ERR_PTR(-EINVAL);
149 return &gdev->descs[hwnum];
151 EXPORT_SYMBOL_GPL(gpiochip_get_desc);
154 * desc_to_gpio - convert a GPIO descriptor to the integer namespace
155 * @desc: GPIO descriptor
157 * This should disappear in the future but is needed since we still
158 * use GPIO numbers for error messages and sysfs nodes.
161 * The global GPIO number for the GPIO specified by its descriptor.
163 int desc_to_gpio(const struct gpio_desc *desc)
165 return desc->gdev->base + (desc - &desc->gdev->descs[0]);
167 EXPORT_SYMBOL_GPL(desc_to_gpio);
171 * gpiod_to_chip - Return the GPIO chip to which a GPIO descriptor belongs
172 * @desc: descriptor to return the chip of
174 struct gpio_chip *gpiod_to_chip(const struct gpio_desc *desc)
176 if (!desc || !desc->gdev)
178 return desc->gdev->chip;
180 EXPORT_SYMBOL_GPL(gpiod_to_chip);
182 /* dynamic allocation of GPIOs, e.g. on a hotplugged device */
183 static int gpiochip_find_base(int ngpio)
185 struct gpio_device *gdev;
186 int base = ARCH_NR_GPIOS - ngpio;
188 list_for_each_entry_reverse(gdev, &gpio_devices, list) {
189 /* found a free space? */
190 if (gdev->base + gdev->ngpio <= base)
192 /* nope, check the space right before the chip */
193 base = gdev->base - ngpio;
196 if (gpio_is_valid(base)) {
197 pr_debug("%s: found new base at %d\n", __func__, base);
200 pr_err("%s: cannot find free range\n", __func__);
206 * gpiod_get_direction - return the current direction of a GPIO
207 * @desc: GPIO to get the direction of
209 * Returns 0 for output, 1 for input, or an error code in case of error.
211 * This function may sleep if gpiod_cansleep() is true.
213 int gpiod_get_direction(struct gpio_desc *desc)
215 struct gpio_chip *gc;
219 gc = gpiod_to_chip(desc);
220 offset = gpio_chip_hwgpio(desc);
223 * Open drain emulation using input mode may incorrectly report
224 * input here, fix that up.
226 if (test_bit(FLAG_OPEN_DRAIN, &desc->flags) &&
227 test_bit(FLAG_IS_OUT, &desc->flags))
230 if (!gc->get_direction)
233 ret = gc->get_direction(gc, offset);
237 /* GPIOF_DIR_IN or other positive, otherwise GPIOF_DIR_OUT */
241 assign_bit(FLAG_IS_OUT, &desc->flags, !ret);
245 EXPORT_SYMBOL_GPL(gpiod_get_direction);
248 * Add a new chip to the global chips list, keeping the list of chips sorted
249 * by range(means [base, base + ngpio - 1]) order.
251 * Return -EBUSY if the new chip overlaps with some other chip's integer
254 static int gpiodev_add_to_list(struct gpio_device *gdev)
256 struct gpio_device *prev, *next;
258 if (list_empty(&gpio_devices)) {
259 /* initial entry in list */
260 list_add_tail(&gdev->list, &gpio_devices);
264 next = list_first_entry(&gpio_devices, struct gpio_device, list);
265 if (gdev->base + gdev->ngpio <= next->base) {
266 /* add before first entry */
267 list_add(&gdev->list, &gpio_devices);
271 prev = list_last_entry(&gpio_devices, struct gpio_device, list);
272 if (prev->base + prev->ngpio <= gdev->base) {
273 /* add behind last entry */
274 list_add_tail(&gdev->list, &gpio_devices);
278 list_for_each_entry_safe(prev, next, &gpio_devices, list) {
279 /* at the end of the list */
280 if (&next->list == &gpio_devices)
283 /* add between prev and next */
284 if (prev->base + prev->ngpio <= gdev->base
285 && gdev->base + gdev->ngpio <= next->base) {
286 list_add(&gdev->list, &prev->list);
295 * Convert a GPIO name to its descriptor
296 * Note that there is no guarantee that GPIO names are globally unique!
297 * Hence this function will return, if it exists, a reference to the first GPIO
298 * line found that matches the given name.
300 static struct gpio_desc *gpio_name_to_desc(const char * const name)
302 struct gpio_device *gdev;
308 spin_lock_irqsave(&gpio_lock, flags);
310 list_for_each_entry(gdev, &gpio_devices, list) {
311 struct gpio_desc *desc;
313 for_each_gpio_desc(gdev->chip, desc) {
314 if (desc->name && !strcmp(desc->name, name)) {
315 spin_unlock_irqrestore(&gpio_lock, flags);
321 spin_unlock_irqrestore(&gpio_lock, flags);
327 * Take the names from gc->names and assign them to their GPIO descriptors.
328 * Warn if a name is already used for a GPIO line on a different GPIO chip.
331 * 1. Non-unique names are still accepted,
332 * 2. Name collisions within the same GPIO chip are not reported.
334 static int gpiochip_set_desc_names(struct gpio_chip *gc)
336 struct gpio_device *gdev = gc->gpiodev;
339 /* First check all names if they are unique */
340 for (i = 0; i != gc->ngpio; ++i) {
341 struct gpio_desc *gpio;
343 gpio = gpio_name_to_desc(gc->names[i]);
346 "Detected name collision for GPIO name '%s'\n",
350 /* Then add all names to the GPIO descriptors */
351 for (i = 0; i != gc->ngpio; ++i)
352 gdev->descs[i].name = gc->names[i];
358 * devprop_gpiochip_set_names - Set GPIO line names using device properties
359 * @chip: GPIO chip whose lines should be named, if possible
361 * Looks for device property "gpio-line-names" and if it exists assigns
362 * GPIO line names for the chip. The memory allocated for the assigned
363 * names belong to the underlying firmware node and should not be released
366 static int devprop_gpiochip_set_names(struct gpio_chip *chip)
368 struct gpio_device *gdev = chip->gpiodev;
369 struct fwnode_handle *fwnode = dev_fwnode(&gdev->dev);
374 count = fwnode_property_string_array_count(fwnode, "gpio-line-names");
379 * When offset is set in the driver side we assume the driver internally
380 * is using more than one gpiochip per the same device. We have to stop
381 * setting friendly names if the specified ones with 'gpio-line-names'
382 * are less than the offset in the device itself. This means all the
383 * lines are not present for every single pin within all the internal
386 if (count <= chip->offset) {
387 dev_warn(&gdev->dev, "gpio-line-names too short (length %d), cannot map names for the gpiochip at offset %u\n",
388 count, chip->offset);
392 names = kcalloc(count, sizeof(*names), GFP_KERNEL);
396 ret = fwnode_property_read_string_array(fwnode, "gpio-line-names",
399 dev_warn(&gdev->dev, "failed to read GPIO line names\n");
405 * When more that one gpiochip per device is used, 'count' can
406 * contain at most number gpiochips x chip->ngpio. We have to
407 * correctly distribute all defined lines taking into account
408 * chip->offset as starting point from where we will assign
409 * the names to pins from the 'names' array. Since property
410 * 'gpio-line-names' cannot contains gaps, we have to be sure
411 * we only assign those pins that really exists since chip->ngpio
412 * can be different of the chip->offset.
414 count = (count > chip->offset) ? count - chip->offset : count;
415 if (count > chip->ngpio)
418 for (i = 0; i < count; i++) {
420 * Allow overriding "fixed" names provided by the GPIO
421 * provider. The "fixed" names are more often than not
422 * generic and less informative than the names given in
425 if (names[chip->offset + i] && names[chip->offset + i][0])
426 gdev->descs[i].name = names[chip->offset + i];
434 static unsigned long *gpiochip_allocate_mask(struct gpio_chip *gc)
438 p = bitmap_alloc(gc->ngpio, GFP_KERNEL);
442 /* Assume by default all GPIOs are valid */
443 bitmap_fill(p, gc->ngpio);
448 static int gpiochip_alloc_valid_mask(struct gpio_chip *gc)
450 if (!(of_gpio_need_valid_mask(gc) || gc->init_valid_mask))
453 gc->valid_mask = gpiochip_allocate_mask(gc);
460 static int gpiochip_init_valid_mask(struct gpio_chip *gc)
462 if (gc->init_valid_mask)
463 return gc->init_valid_mask(gc,
470 static void gpiochip_free_valid_mask(struct gpio_chip *gc)
472 bitmap_free(gc->valid_mask);
473 gc->valid_mask = NULL;
476 static int gpiochip_add_pin_ranges(struct gpio_chip *gc)
478 if (gc->add_pin_ranges)
479 return gc->add_pin_ranges(gc);
484 bool gpiochip_line_is_valid(const struct gpio_chip *gc,
487 /* No mask means all valid */
488 if (likely(!gc->valid_mask))
490 return test_bit(offset, gc->valid_mask);
492 EXPORT_SYMBOL_GPL(gpiochip_line_is_valid);
494 static void gpiodevice_release(struct device *dev)
496 struct gpio_device *gdev = container_of(dev, struct gpio_device, dev);
499 spin_lock_irqsave(&gpio_lock, flags);
500 list_del(&gdev->list);
501 spin_unlock_irqrestore(&gpio_lock, flags);
503 ida_free(&gpio_ida, gdev->id);
504 kfree_const(gdev->label);
509 #ifdef CONFIG_GPIO_CDEV
510 #define gcdev_register(gdev, devt) gpiolib_cdev_register((gdev), (devt))
511 #define gcdev_unregister(gdev) gpiolib_cdev_unregister((gdev))
514 * gpiolib_cdev_register() indirectly calls device_add(), which is still
515 * required even when cdev is not selected.
517 #define gcdev_register(gdev, devt) device_add(&(gdev)->dev)
518 #define gcdev_unregister(gdev) device_del(&(gdev)->dev)
521 static int gpiochip_setup_dev(struct gpio_device *gdev)
525 ret = gcdev_register(gdev, gpio_devt);
529 /* From this point, the .release() function cleans up gpio_device */
530 gdev->dev.release = gpiodevice_release;
532 ret = gpiochip_sysfs_register(gdev);
534 goto err_remove_device;
536 dev_dbg(&gdev->dev, "registered GPIOs %d to %d on %s\n", gdev->base,
537 gdev->base + gdev->ngpio - 1, gdev->chip->label ? : "generic");
542 gcdev_unregister(gdev);
546 static void gpiochip_machine_hog(struct gpio_chip *gc, struct gpiod_hog *hog)
548 struct gpio_desc *desc;
551 desc = gpiochip_get_desc(gc, hog->chip_hwnum);
553 chip_err(gc, "%s: unable to get GPIO desc: %ld\n", __func__,
558 if (test_bit(FLAG_IS_HOGGED, &desc->flags))
561 rv = gpiod_hog(desc, hog->line_name, hog->lflags, hog->dflags);
563 gpiod_err(desc, "%s: unable to hog GPIO line (%s:%u): %d\n",
564 __func__, gc->label, hog->chip_hwnum, rv);
567 static void machine_gpiochip_add(struct gpio_chip *gc)
569 struct gpiod_hog *hog;
571 mutex_lock(&gpio_machine_hogs_mutex);
573 list_for_each_entry(hog, &gpio_machine_hogs, list) {
574 if (!strcmp(gc->label, hog->chip_label))
575 gpiochip_machine_hog(gc, hog);
578 mutex_unlock(&gpio_machine_hogs_mutex);
581 static void gpiochip_setup_devs(void)
583 struct gpio_device *gdev;
586 list_for_each_entry(gdev, &gpio_devices, list) {
587 ret = gpiochip_setup_dev(gdev);
590 "Failed to initialize gpio device (%d)\n", ret);
594 int gpiochip_add_data_with_key(struct gpio_chip *gc, void *data,
595 struct lock_class_key *lock_key,
596 struct lock_class_key *request_key)
598 struct fwnode_handle *fwnode = NULL;
599 struct gpio_device *gdev;
609 fwnode = dev_fwnode(gc->parent);
612 * First: allocate and populate the internal stat container, and
613 * set up the struct device.
615 gdev = kzalloc(sizeof(*gdev), GFP_KERNEL);
618 gdev->dev.bus = &gpio_bus_type;
619 gdev->dev.parent = gc->parent;
623 of_gpio_dev_init(gc, gdev);
624 acpi_gpio_dev_init(gc, gdev);
627 * Assign fwnode depending on the result of the previous calls,
628 * if none of them succeed, assign it to the parent's one.
630 gdev->dev.fwnode = dev_fwnode(&gdev->dev) ?: fwnode;
632 gdev->id = ida_alloc(&gpio_ida, GFP_KERNEL);
638 ret = dev_set_name(&gdev->dev, GPIOCHIP_NAME "%d", gdev->id);
642 device_initialize(&gdev->dev);
643 if (gc->parent && gc->parent->driver)
644 gdev->owner = gc->parent->driver->owner;
646 /* TODO: remove chip->owner */
647 gdev->owner = gc->owner;
649 gdev->owner = THIS_MODULE;
652 * Try the device properties if the driver didn't supply the number
657 ret = device_property_read_u32(&gdev->dev, "ngpios", &ngpios);
660 * -ENODATA means that there is no property found and
661 * we want to issue the error message to the user.
662 * Besides that, we want to return different error code
663 * to state that supplied value is not valid.
667 goto err_free_dev_name;
672 if (gc->ngpio == 0) {
673 chip_err(gc, "tried to insert a GPIO chip with zero lines\n");
675 goto err_free_dev_name;
678 if (gc->ngpio > FASTPATH_NGPIO)
679 chip_warn(gc, "line cnt %u is greater than fast path cnt %u\n",
680 gc->ngpio, FASTPATH_NGPIO);
682 gdev->descs = kcalloc(gc->ngpio, sizeof(*gdev->descs), GFP_KERNEL);
685 goto err_free_dev_name;
688 gdev->label = kstrdup_const(gc->label ?: "unknown", GFP_KERNEL);
694 gdev->ngpio = gc->ngpio;
697 spin_lock_irqsave(&gpio_lock, flags);
700 * TODO: this allocates a Linux GPIO number base in the global
701 * GPIO numberspace for this chip. In the long run we want to
702 * get *rid* of this numberspace and use only descriptors, but
703 * it may be a pipe dream. It will not happen before we get rid
704 * of the sysfs interface anyways.
708 base = gpiochip_find_base(gc->ngpio);
710 spin_unlock_irqrestore(&gpio_lock, flags);
716 * TODO: it should not be necessary to reflect the assigned
717 * base outside of the GPIO subsystem. Go over drivers and
718 * see if anyone makes use of this, else drop this and assign
725 ret = gpiodev_add_to_list(gdev);
727 spin_unlock_irqrestore(&gpio_lock, flags);
728 chip_err(gc, "GPIO integer space overlap, cannot add chip\n");
732 for (i = 0; i < gc->ngpio; i++)
733 gdev->descs[i].gdev = gdev;
735 spin_unlock_irqrestore(&gpio_lock, flags);
737 BLOCKING_INIT_NOTIFIER_HEAD(&gdev->notifier);
738 init_rwsem(&gdev->sem);
740 #ifdef CONFIG_PINCTRL
741 INIT_LIST_HEAD(&gdev->pin_ranges);
745 ret = gpiochip_set_desc_names(gc);
747 goto err_remove_from_list;
749 ret = devprop_gpiochip_set_names(gc);
751 goto err_remove_from_list;
753 ret = gpiochip_alloc_valid_mask(gc);
755 goto err_remove_from_list;
757 ret = of_gpiochip_add(gc);
759 goto err_free_gpiochip_mask;
761 ret = gpiochip_init_valid_mask(gc);
763 goto err_remove_of_chip;
765 for (i = 0; i < gc->ngpio; i++) {
766 struct gpio_desc *desc = &gdev->descs[i];
768 if (gc->get_direction && gpiochip_line_is_valid(gc, i)) {
769 assign_bit(FLAG_IS_OUT,
770 &desc->flags, !gc->get_direction(gc, i));
772 assign_bit(FLAG_IS_OUT,
773 &desc->flags, !gc->direction_input);
777 ret = gpiochip_add_pin_ranges(gc);
779 goto err_remove_of_chip;
781 acpi_gpiochip_add(gc);
783 machine_gpiochip_add(gc);
785 ret = gpiochip_irqchip_init_valid_mask(gc);
787 goto err_remove_acpi_chip;
789 ret = gpiochip_irqchip_init_hw(gc);
791 goto err_remove_acpi_chip;
793 ret = gpiochip_add_irqchip(gc, lock_key, request_key);
795 goto err_remove_irqchip_mask;
798 * By first adding the chardev, and then adding the device,
799 * we get a device node entry in sysfs under
800 * /sys/bus/gpio/devices/gpiochipN/dev that can be used for
801 * coldplug of device nodes and other udev business.
802 * We can do this only if gpiolib has been initialized.
803 * Otherwise, defer until later.
805 if (gpiolib_initialized) {
806 ret = gpiochip_setup_dev(gdev);
808 goto err_remove_irqchip;
813 gpiochip_irqchip_remove(gc);
814 err_remove_irqchip_mask:
815 gpiochip_irqchip_free_valid_mask(gc);
816 err_remove_acpi_chip:
817 acpi_gpiochip_remove(gc);
819 gpiochip_free_hogs(gc);
820 of_gpiochip_remove(gc);
821 err_free_gpiochip_mask:
822 gpiochip_remove_pin_ranges(gc);
823 gpiochip_free_valid_mask(gc);
824 if (gdev->dev.release) {
825 /* release() has been registered by gpiochip_setup_dev() */
826 put_device(&gdev->dev);
827 goto err_print_message;
829 err_remove_from_list:
830 spin_lock_irqsave(&gpio_lock, flags);
831 list_del(&gdev->list);
832 spin_unlock_irqrestore(&gpio_lock, flags);
834 kfree_const(gdev->label);
838 kfree(dev_name(&gdev->dev));
840 ida_free(&gpio_ida, gdev->id);
844 /* failures here can mean systems won't boot... */
845 if (ret != -EPROBE_DEFER) {
846 pr_err("%s: GPIOs %d..%d (%s) failed to register, %d\n", __func__,
847 base, base + (int)ngpios - 1,
848 gc->label ? : "generic", ret);
852 EXPORT_SYMBOL_GPL(gpiochip_add_data_with_key);
855 * gpiochip_get_data() - get per-subdriver data for the chip
859 * The per-subdriver data for the chip.
861 void *gpiochip_get_data(struct gpio_chip *gc)
863 return gc->gpiodev->data;
865 EXPORT_SYMBOL_GPL(gpiochip_get_data);
868 * gpiochip_remove() - unregister a gpio_chip
869 * @gc: the chip to unregister
871 * A gpio_chip with any GPIOs still requested may not be removed.
873 void gpiochip_remove(struct gpio_chip *gc)
875 struct gpio_device *gdev = gc->gpiodev;
879 down_write(&gdev->sem);
881 /* FIXME: should the legacy sysfs handling be moved to gpio_device? */
882 gpiochip_sysfs_unregister(gdev);
883 gpiochip_free_hogs(gc);
884 /* Numb the device, cancelling all outstanding operations */
886 gpiochip_irqchip_remove(gc);
887 acpi_gpiochip_remove(gc);
888 of_gpiochip_remove(gc);
889 gpiochip_remove_pin_ranges(gc);
890 gpiochip_free_valid_mask(gc);
892 * We accept no more calls into the driver from this point, so
893 * NULL the driver data pointer
897 spin_lock_irqsave(&gpio_lock, flags);
898 for (i = 0; i < gdev->ngpio; i++) {
899 if (gpiochip_is_requested(gc, i))
902 spin_unlock_irqrestore(&gpio_lock, flags);
904 if (i != gdev->ngpio)
906 "REMOVING GPIOCHIP WITH GPIOS STILL REQUESTED\n");
909 * The gpiochip side puts its use of the device to rest here:
910 * if there are no userspace clients, the chardev and device will
911 * be removed, else it will be dangling until the last user is
914 gcdev_unregister(gdev);
915 up_write(&gdev->sem);
916 put_device(&gdev->dev);
918 EXPORT_SYMBOL_GPL(gpiochip_remove);
921 * gpiochip_find() - iterator for locating a specific gpio_chip
922 * @data: data to pass to match function
923 * @match: Callback function to check gpio_chip
925 * Similar to bus_find_device. It returns a reference to a gpio_chip as
926 * determined by a user supplied @match callback. The callback should return
927 * 0 if the device doesn't match and non-zero if it does. If the callback is
928 * non-zero, this function will return to the caller and not iterate over any
931 struct gpio_chip *gpiochip_find(void *data,
932 int (*match)(struct gpio_chip *gc,
935 struct gpio_device *gdev;
936 struct gpio_chip *gc = NULL;
939 spin_lock_irqsave(&gpio_lock, flags);
940 list_for_each_entry(gdev, &gpio_devices, list)
941 if (gdev->chip && match(gdev->chip, data)) {
946 spin_unlock_irqrestore(&gpio_lock, flags);
950 EXPORT_SYMBOL_GPL(gpiochip_find);
952 static int gpiochip_match_name(struct gpio_chip *gc, void *data)
954 const char *name = data;
956 return !strcmp(gc->label, name);
959 static struct gpio_chip *find_chip_by_name(const char *name)
961 return gpiochip_find((void *)name, gpiochip_match_name);
964 #ifdef CONFIG_GPIOLIB_IRQCHIP
967 * The following is irqchip helper code for gpiochips.
970 static int gpiochip_irqchip_init_hw(struct gpio_chip *gc)
972 struct gpio_irq_chip *girq = &gc->irq;
977 return girq->init_hw(gc);
980 static int gpiochip_irqchip_init_valid_mask(struct gpio_chip *gc)
982 struct gpio_irq_chip *girq = &gc->irq;
984 if (!girq->init_valid_mask)
987 girq->valid_mask = gpiochip_allocate_mask(gc);
988 if (!girq->valid_mask)
991 girq->init_valid_mask(gc, girq->valid_mask, gc->ngpio);
996 static void gpiochip_irqchip_free_valid_mask(struct gpio_chip *gc)
998 bitmap_free(gc->irq.valid_mask);
999 gc->irq.valid_mask = NULL;
1002 bool gpiochip_irqchip_irq_valid(const struct gpio_chip *gc,
1003 unsigned int offset)
1005 if (!gpiochip_line_is_valid(gc, offset))
1007 /* No mask means all valid */
1008 if (likely(!gc->irq.valid_mask))
1010 return test_bit(offset, gc->irq.valid_mask);
1012 EXPORT_SYMBOL_GPL(gpiochip_irqchip_irq_valid);
1014 #ifdef CONFIG_IRQ_DOMAIN_HIERARCHY
1017 * gpiochip_set_hierarchical_irqchip() - connects a hierarchical irqchip
1019 * @gc: the gpiochip to set the irqchip hierarchical handler to
1020 * @irqchip: the irqchip to handle this level of the hierarchy, the interrupt
1021 * will then percolate up to the parent
1023 static void gpiochip_set_hierarchical_irqchip(struct gpio_chip *gc,
1024 struct irq_chip *irqchip)
1026 /* DT will deal with mapping each IRQ as we go along */
1027 if (is_of_node(gc->irq.fwnode))
1031 * This is for legacy and boardfile "irqchip" fwnodes: allocate
1032 * irqs upfront instead of dynamically since we don't have the
1033 * dynamic type of allocation that hardware description languages
1034 * provide. Once all GPIO drivers using board files are gone from
1035 * the kernel we can delete this code, but for a transitional period
1036 * it is necessary to keep this around.
1038 if (is_fwnode_irqchip(gc->irq.fwnode)) {
1042 for (i = 0; i < gc->ngpio; i++) {
1043 struct irq_fwspec fwspec;
1044 unsigned int parent_hwirq;
1045 unsigned int parent_type;
1046 struct gpio_irq_chip *girq = &gc->irq;
1049 * We call the child to parent translation function
1050 * only to check if the child IRQ is valid or not.
1051 * Just pick the rising edge type here as that is what
1052 * we likely need to support.
1054 ret = girq->child_to_parent_hwirq(gc, i,
1055 IRQ_TYPE_EDGE_RISING,
1059 chip_err(gc, "skip set-up on hwirq %d\n",
1064 fwspec.fwnode = gc->irq.fwnode;
1065 /* This is the hwirq for the GPIO line side of things */
1066 fwspec.param[0] = girq->child_offset_to_irq(gc, i);
1067 /* Just pick something */
1068 fwspec.param[1] = IRQ_TYPE_EDGE_RISING;
1069 fwspec.param_count = 2;
1070 ret = __irq_domain_alloc_irqs(gc->irq.domain,
1071 /* just pick something */
1080 "can not allocate irq for GPIO line %d parent hwirq %d in hierarchy domain: %d\n",
1087 chip_err(gc, "%s unknown fwnode type proceed anyway\n", __func__);
1092 static int gpiochip_hierarchy_irq_domain_translate(struct irq_domain *d,
1093 struct irq_fwspec *fwspec,
1094 unsigned long *hwirq,
1097 /* We support standard DT translation */
1098 if (is_of_node(fwspec->fwnode) && fwspec->param_count == 2) {
1099 return irq_domain_translate_twocell(d, fwspec, hwirq, type);
1102 /* This is for board files and others not using DT */
1103 if (is_fwnode_irqchip(fwspec->fwnode)) {
1106 ret = irq_domain_translate_twocell(d, fwspec, hwirq, type);
1109 WARN_ON(*type == IRQ_TYPE_NONE);
1115 static int gpiochip_hierarchy_irq_domain_alloc(struct irq_domain *d,
1117 unsigned int nr_irqs,
1120 struct gpio_chip *gc = d->host_data;
1121 irq_hw_number_t hwirq;
1122 unsigned int type = IRQ_TYPE_NONE;
1123 struct irq_fwspec *fwspec = data;
1124 union gpio_irq_fwspec gpio_parent_fwspec = {};
1125 unsigned int parent_hwirq;
1126 unsigned int parent_type;
1127 struct gpio_irq_chip *girq = &gc->irq;
1131 * The nr_irqs parameter is always one except for PCI multi-MSI
1132 * so this should not happen.
1134 WARN_ON(nr_irqs != 1);
1136 ret = gc->irq.child_irq_domain_ops.translate(d, fwspec, &hwirq, &type);
1140 chip_dbg(gc, "allocate IRQ %d, hwirq %lu\n", irq, hwirq);
1142 ret = girq->child_to_parent_hwirq(gc, hwirq, type,
1143 &parent_hwirq, &parent_type);
1145 chip_err(gc, "can't look up hwirq %lu\n", hwirq);
1148 chip_dbg(gc, "found parent hwirq %u\n", parent_hwirq);
1151 * We set handle_bad_irq because the .set_type() should
1152 * always be invoked and set the right type of handler.
1154 irq_domain_set_info(d,
1163 /* This parent only handles asserted level IRQs */
1164 ret = girq->populate_parent_alloc_arg(gc, &gpio_parent_fwspec,
1165 parent_hwirq, parent_type);
1169 chip_dbg(gc, "alloc_irqs_parent for %d parent hwirq %d\n",
1171 irq_set_lockdep_class(irq, gc->irq.lock_key, gc->irq.request_key);
1172 ret = irq_domain_alloc_irqs_parent(d, irq, 1, &gpio_parent_fwspec);
1174 * If the parent irqdomain is msi, the interrupts have already
1175 * been allocated, so the EEXIST is good.
1177 if (irq_domain_is_msi(d->parent) && (ret == -EEXIST))
1181 "failed to allocate parent hwirq %d for hwirq %lu\n",
1182 parent_hwirq, hwirq);
1187 static unsigned int gpiochip_child_offset_to_irq_noop(struct gpio_chip *gc,
1188 unsigned int offset)
1193 static void gpiochip_hierarchy_setup_domain_ops(struct irq_domain_ops *ops)
1195 ops->activate = gpiochip_irq_domain_activate;
1196 ops->deactivate = gpiochip_irq_domain_deactivate;
1197 ops->alloc = gpiochip_hierarchy_irq_domain_alloc;
1200 * We only allow overriding the translate() and free() functions for
1201 * hierarchical chips, and this should only be done if the user
1202 * really need something other than 1:1 translation for translate()
1203 * callback and free if user wants to free up any resources which
1204 * were allocated during callbacks, for example populate_parent_alloc_arg.
1206 if (!ops->translate)
1207 ops->translate = gpiochip_hierarchy_irq_domain_translate;
1209 ops->free = irq_domain_free_irqs_common;
1212 static int gpiochip_hierarchy_add_domain(struct gpio_chip *gc)
1214 if (!gc->irq.child_to_parent_hwirq ||
1216 chip_err(gc, "missing irqdomain vital data\n");
1220 if (!gc->irq.child_offset_to_irq)
1221 gc->irq.child_offset_to_irq = gpiochip_child_offset_to_irq_noop;
1223 if (!gc->irq.populate_parent_alloc_arg)
1224 gc->irq.populate_parent_alloc_arg =
1225 gpiochip_populate_parent_fwspec_twocell;
1227 gpiochip_hierarchy_setup_domain_ops(&gc->irq.child_irq_domain_ops);
1229 gc->irq.domain = irq_domain_create_hierarchy(
1230 gc->irq.parent_domain,
1234 &gc->irq.child_irq_domain_ops,
1237 if (!gc->irq.domain)
1240 gpiochip_set_hierarchical_irqchip(gc, gc->irq.chip);
1245 static bool gpiochip_hierarchy_is_hierarchical(struct gpio_chip *gc)
1247 return !!gc->irq.parent_domain;
1250 int gpiochip_populate_parent_fwspec_twocell(struct gpio_chip *gc,
1251 union gpio_irq_fwspec *gfwspec,
1252 unsigned int parent_hwirq,
1253 unsigned int parent_type)
1255 struct irq_fwspec *fwspec = &gfwspec->fwspec;
1257 fwspec->fwnode = gc->irq.parent_domain->fwnode;
1258 fwspec->param_count = 2;
1259 fwspec->param[0] = parent_hwirq;
1260 fwspec->param[1] = parent_type;
1264 EXPORT_SYMBOL_GPL(gpiochip_populate_parent_fwspec_twocell);
1266 int gpiochip_populate_parent_fwspec_fourcell(struct gpio_chip *gc,
1267 union gpio_irq_fwspec *gfwspec,
1268 unsigned int parent_hwirq,
1269 unsigned int parent_type)
1271 struct irq_fwspec *fwspec = &gfwspec->fwspec;
1273 fwspec->fwnode = gc->irq.parent_domain->fwnode;
1274 fwspec->param_count = 4;
1275 fwspec->param[0] = 0;
1276 fwspec->param[1] = parent_hwirq;
1277 fwspec->param[2] = 0;
1278 fwspec->param[3] = parent_type;
1282 EXPORT_SYMBOL_GPL(gpiochip_populate_parent_fwspec_fourcell);
1286 static int gpiochip_hierarchy_add_domain(struct gpio_chip *gc)
1291 static bool gpiochip_hierarchy_is_hierarchical(struct gpio_chip *gc)
1296 #endif /* CONFIG_IRQ_DOMAIN_HIERARCHY */
1299 * gpiochip_irq_map() - maps an IRQ into a GPIO irqchip
1300 * @d: the irqdomain used by this irqchip
1301 * @irq: the global irq number used by this GPIO irqchip irq
1302 * @hwirq: the local IRQ/GPIO line offset on this gpiochip
1304 * This function will set up the mapping for a certain IRQ line on a
1305 * gpiochip by assigning the gpiochip as chip data, and using the irqchip
1306 * stored inside the gpiochip.
1308 int gpiochip_irq_map(struct irq_domain *d, unsigned int irq,
1309 irq_hw_number_t hwirq)
1311 struct gpio_chip *gc = d->host_data;
1314 if (!gpiochip_irqchip_irq_valid(gc, hwirq))
1317 irq_set_chip_data(irq, gc);
1319 * This lock class tells lockdep that GPIO irqs are in a different
1320 * category than their parents, so it won't report false recursion.
1322 irq_set_lockdep_class(irq, gc->irq.lock_key, gc->irq.request_key);
1323 irq_set_chip_and_handler(irq, gc->irq.chip, gc->irq.handler);
1324 /* Chips that use nested thread handlers have them marked */
1325 if (gc->irq.threaded)
1326 irq_set_nested_thread(irq, 1);
1327 irq_set_noprobe(irq);
1329 if (gc->irq.num_parents == 1)
1330 ret = irq_set_parent(irq, gc->irq.parents[0]);
1331 else if (gc->irq.map)
1332 ret = irq_set_parent(irq, gc->irq.map[hwirq]);
1338 * No set-up of the hardware will happen if IRQ_TYPE_NONE
1339 * is passed as default type.
1341 if (gc->irq.default_type != IRQ_TYPE_NONE)
1342 irq_set_irq_type(irq, gc->irq.default_type);
1346 EXPORT_SYMBOL_GPL(gpiochip_irq_map);
1348 void gpiochip_irq_unmap(struct irq_domain *d, unsigned int irq)
1350 struct gpio_chip *gc = d->host_data;
1352 if (gc->irq.threaded)
1353 irq_set_nested_thread(irq, 0);
1354 irq_set_chip_and_handler(irq, NULL, NULL);
1355 irq_set_chip_data(irq, NULL);
1357 EXPORT_SYMBOL_GPL(gpiochip_irq_unmap);
1359 static const struct irq_domain_ops gpiochip_domain_ops = {
1360 .map = gpiochip_irq_map,
1361 .unmap = gpiochip_irq_unmap,
1362 /* Virtually all GPIO irqchips are twocell:ed */
1363 .xlate = irq_domain_xlate_twocell,
1367 * TODO: move these activate/deactivate in under the hierarchicial
1368 * irqchip implementation as static once SPMI and SSBI (all external
1369 * users) are phased over.
1372 * gpiochip_irq_domain_activate() - Lock a GPIO to be used as an IRQ
1373 * @domain: The IRQ domain used by this IRQ chip
1374 * @data: Outermost irq_data associated with the IRQ
1375 * @reserve: If set, only reserve an interrupt vector instead of assigning one
1377 * This function is a wrapper that calls gpiochip_lock_as_irq() and is to be
1378 * used as the activate function for the &struct irq_domain_ops. The host_data
1379 * for the IRQ domain must be the &struct gpio_chip.
1381 int gpiochip_irq_domain_activate(struct irq_domain *domain,
1382 struct irq_data *data, bool reserve)
1384 struct gpio_chip *gc = domain->host_data;
1386 return gpiochip_lock_as_irq(gc, data->hwirq);
1388 EXPORT_SYMBOL_GPL(gpiochip_irq_domain_activate);
1391 * gpiochip_irq_domain_deactivate() - Unlock a GPIO used as an IRQ
1392 * @domain: The IRQ domain used by this IRQ chip
1393 * @data: Outermost irq_data associated with the IRQ
1395 * This function is a wrapper that will call gpiochip_unlock_as_irq() and is to
1396 * be used as the deactivate function for the &struct irq_domain_ops. The
1397 * host_data for the IRQ domain must be the &struct gpio_chip.
1399 void gpiochip_irq_domain_deactivate(struct irq_domain *domain,
1400 struct irq_data *data)
1402 struct gpio_chip *gc = domain->host_data;
1404 return gpiochip_unlock_as_irq(gc, data->hwirq);
1406 EXPORT_SYMBOL_GPL(gpiochip_irq_domain_deactivate);
1408 static int gpiochip_to_irq(struct gpio_chip *gc, unsigned int offset)
1410 struct irq_domain *domain = gc->irq.domain;
1412 #ifdef CONFIG_GPIOLIB_IRQCHIP
1414 * Avoid race condition with other code, which tries to lookup
1415 * an IRQ before the irqchip has been properly registered,
1416 * i.e. while gpiochip is still being brought up.
1418 if (!gc->irq.initialized)
1419 return -EPROBE_DEFER;
1422 if (!gpiochip_irqchip_irq_valid(gc, offset))
1425 #ifdef CONFIG_IRQ_DOMAIN_HIERARCHY
1426 if (irq_domain_is_hierarchy(domain)) {
1427 struct irq_fwspec spec;
1429 spec.fwnode = domain->fwnode;
1430 spec.param_count = 2;
1431 spec.param[0] = gc->irq.child_offset_to_irq(gc, offset);
1432 spec.param[1] = IRQ_TYPE_NONE;
1434 return irq_create_fwspec_mapping(&spec);
1438 return irq_create_mapping(domain, offset);
1441 int gpiochip_irq_reqres(struct irq_data *d)
1443 struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
1445 return gpiochip_reqres_irq(gc, d->hwirq);
1447 EXPORT_SYMBOL(gpiochip_irq_reqres);
1449 void gpiochip_irq_relres(struct irq_data *d)
1451 struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
1453 gpiochip_relres_irq(gc, d->hwirq);
1455 EXPORT_SYMBOL(gpiochip_irq_relres);
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->flags & IRQCHIP_IMMUTABLE)
1498 chip_warn(gc, "not an immutable chip, please consider fixing it!\n");
1500 if (!irqchip->irq_request_resources &&
1501 !irqchip->irq_release_resources) {
1502 irqchip->irq_request_resources = gpiochip_irq_reqres;
1503 irqchip->irq_release_resources = gpiochip_irq_relres;
1505 if (WARN_ON(gc->irq.irq_enable))
1507 /* Check if the irqchip already has this hook... */
1508 if (irqchip->irq_enable == gpiochip_irq_enable ||
1509 irqchip->irq_mask == gpiochip_irq_mask) {
1511 * ...and if so, give a gentle warning that this is bad
1515 "detected irqchip that is shared with multiple gpiochips: please fix the driver.\n");
1519 if (irqchip->irq_disable) {
1520 gc->irq.irq_disable = irqchip->irq_disable;
1521 irqchip->irq_disable = gpiochip_irq_disable;
1523 gc->irq.irq_mask = irqchip->irq_mask;
1524 irqchip->irq_mask = gpiochip_irq_mask;
1527 if (irqchip->irq_enable) {
1528 gc->irq.irq_enable = irqchip->irq_enable;
1529 irqchip->irq_enable = gpiochip_irq_enable;
1531 gc->irq.irq_unmask = irqchip->irq_unmask;
1532 irqchip->irq_unmask = gpiochip_irq_unmask;
1537 * gpiochip_add_irqchip() - adds an IRQ chip to a GPIO chip
1538 * @gc: the GPIO chip to add the IRQ chip to
1539 * @lock_key: lockdep class for IRQ lock
1540 * @request_key: lockdep class for IRQ request
1542 static int gpiochip_add_irqchip(struct gpio_chip *gc,
1543 struct lock_class_key *lock_key,
1544 struct lock_class_key *request_key)
1546 struct fwnode_handle *fwnode = dev_fwnode(&gc->gpiodev->dev);
1547 struct irq_chip *irqchip = gc->irq.chip;
1554 if (gc->irq.parent_handler && gc->can_sleep) {
1555 chip_err(gc, "you cannot have chained interrupts on a chip that may sleep\n");
1559 type = gc->irq.default_type;
1562 * Specifying a default trigger is a terrible idea if DT or ACPI is
1563 * used to configure the interrupts, as you may end up with
1564 * conflicting triggers. Tell the user, and reset to NONE.
1566 if (WARN(fwnode && type != IRQ_TYPE_NONE,
1567 "%pfw: Ignoring %u default trigger\n", fwnode, type))
1568 type = IRQ_TYPE_NONE;
1571 chip_warn(gc, "to_irq is redefined in %s and you shouldn't rely on it\n", __func__);
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 gc->irq.domain = irq_domain_create_simple(fwnode,
1588 gc->irq.domain_ops ?: &gpiochip_domain_ops,
1590 if (!gc->irq.domain)
1594 if (gc->irq.parent_handler) {
1595 for (i = 0; i < gc->irq.num_parents; i++) {
1598 if (gc->irq.per_parent_data)
1599 data = gc->irq.parent_handler_data_array[i];
1601 data = gc->irq.parent_handler_data ?: gc;
1604 * The parent IRQ chip is already using the chip_data
1605 * for this IRQ chip, so our callbacks simply use the
1608 irq_set_chained_handler_and_data(gc->irq.parents[i],
1609 gc->irq.parent_handler,
1614 gpiochip_set_irq_hooks(gc);
1617 * Using barrier() here to prevent compiler from reordering
1618 * gc->irq.initialized before initialization of above
1619 * GPIO chip irq members.
1623 gc->irq.initialized = true;
1625 acpi_gpiochip_request_interrupts(gc);
1631 * gpiochip_irqchip_remove() - removes an irqchip added to a gpiochip
1632 * @gc: the gpiochip to remove the irqchip from
1634 * This is called only from gpiochip_remove()
1636 static void gpiochip_irqchip_remove(struct gpio_chip *gc)
1638 struct irq_chip *irqchip = gc->irq.chip;
1639 unsigned int offset;
1641 acpi_gpiochip_free_interrupts(gc);
1643 if (irqchip && gc->irq.parent_handler) {
1644 struct gpio_irq_chip *irq = &gc->irq;
1647 for (i = 0; i < irq->num_parents; i++)
1648 irq_set_chained_handler_and_data(irq->parents[i],
1652 /* Remove all IRQ mappings and delete the domain */
1653 if (gc->irq.domain) {
1656 for (offset = 0; offset < gc->ngpio; offset++) {
1657 if (!gpiochip_irqchip_irq_valid(gc, offset))
1660 irq = irq_find_mapping(gc->irq.domain, offset);
1661 irq_dispose_mapping(irq);
1664 irq_domain_remove(gc->irq.domain);
1667 if (irqchip && !(irqchip->flags & IRQCHIP_IMMUTABLE)) {
1668 if (irqchip->irq_request_resources == gpiochip_irq_reqres) {
1669 irqchip->irq_request_resources = NULL;
1670 irqchip->irq_release_resources = NULL;
1672 if (irqchip->irq_enable == gpiochip_irq_enable) {
1673 irqchip->irq_enable = gc->irq.irq_enable;
1674 irqchip->irq_disable = gc->irq.irq_disable;
1677 gc->irq.irq_enable = NULL;
1678 gc->irq.irq_disable = NULL;
1679 gc->irq.chip = NULL;
1681 gpiochip_irqchip_free_valid_mask(gc);
1685 * gpiochip_irqchip_add_domain() - adds an irqdomain to a gpiochip
1686 * @gc: the gpiochip to add the irqchip to
1687 * @domain: the irqdomain to add to the gpiochip
1689 * This function adds an IRQ domain to the gpiochip.
1691 int gpiochip_irqchip_add_domain(struct gpio_chip *gc,
1692 struct irq_domain *domain)
1697 gc->to_irq = gpiochip_to_irq;
1698 gc->irq.domain = domain;
1702 EXPORT_SYMBOL_GPL(gpiochip_irqchip_add_domain);
1704 #else /* CONFIG_GPIOLIB_IRQCHIP */
1706 static inline int gpiochip_add_irqchip(struct gpio_chip *gc,
1707 struct lock_class_key *lock_key,
1708 struct lock_class_key *request_key)
1712 static void gpiochip_irqchip_remove(struct gpio_chip *gc) {}
1714 static inline int gpiochip_irqchip_init_hw(struct gpio_chip *gc)
1719 static inline int gpiochip_irqchip_init_valid_mask(struct gpio_chip *gc)
1723 static inline void gpiochip_irqchip_free_valid_mask(struct gpio_chip *gc)
1726 #endif /* CONFIG_GPIOLIB_IRQCHIP */
1729 * gpiochip_generic_request() - request the gpio function for a pin
1730 * @gc: the gpiochip owning the GPIO
1731 * @offset: the offset of the GPIO to request for GPIO function
1733 int gpiochip_generic_request(struct gpio_chip *gc, unsigned int offset)
1735 #ifdef CONFIG_PINCTRL
1736 if (list_empty(&gc->gpiodev->pin_ranges))
1740 return pinctrl_gpio_request(gc->gpiodev->base + offset);
1742 EXPORT_SYMBOL_GPL(gpiochip_generic_request);
1745 * gpiochip_generic_free() - free the gpio function from a pin
1746 * @gc: the gpiochip to request the gpio function for
1747 * @offset: the offset of the GPIO to free from GPIO function
1749 void gpiochip_generic_free(struct gpio_chip *gc, unsigned int offset)
1751 #ifdef CONFIG_PINCTRL
1752 if (list_empty(&gc->gpiodev->pin_ranges))
1756 pinctrl_gpio_free(gc->gpiodev->base + offset);
1758 EXPORT_SYMBOL_GPL(gpiochip_generic_free);
1761 * gpiochip_generic_config() - apply configuration for a pin
1762 * @gc: the gpiochip owning the GPIO
1763 * @offset: the offset of the GPIO to apply the configuration
1764 * @config: the configuration to be applied
1766 int gpiochip_generic_config(struct gpio_chip *gc, unsigned int offset,
1767 unsigned long config)
1769 return pinctrl_gpio_set_config(gc->gpiodev->base + offset, config);
1771 EXPORT_SYMBOL_GPL(gpiochip_generic_config);
1773 #ifdef CONFIG_PINCTRL
1776 * gpiochip_add_pingroup_range() - add a range for GPIO <-> pin mapping
1777 * @gc: the gpiochip to add the range for
1778 * @pctldev: the pin controller to map to
1779 * @gpio_offset: the start offset in the current gpio_chip number space
1780 * @pin_group: name of the pin group inside the pin controller
1782 * Calling this function directly from a DeviceTree-supported
1783 * pinctrl driver is DEPRECATED. Please see Section 2.1 of
1784 * Documentation/devicetree/bindings/gpio/gpio.txt on how to
1785 * bind pinctrl and gpio drivers via the "gpio-ranges" property.
1787 int gpiochip_add_pingroup_range(struct gpio_chip *gc,
1788 struct pinctrl_dev *pctldev,
1789 unsigned int gpio_offset, const char *pin_group)
1791 struct gpio_pin_range *pin_range;
1792 struct gpio_device *gdev = gc->gpiodev;
1795 pin_range = kzalloc(sizeof(*pin_range), GFP_KERNEL);
1797 chip_err(gc, "failed to allocate pin ranges\n");
1801 /* Use local offset as range ID */
1802 pin_range->range.id = gpio_offset;
1803 pin_range->range.gc = gc;
1804 pin_range->range.name = gc->label;
1805 pin_range->range.base = gdev->base + gpio_offset;
1806 pin_range->pctldev = pctldev;
1808 ret = pinctrl_get_group_pins(pctldev, pin_group,
1809 &pin_range->range.pins,
1810 &pin_range->range.npins);
1816 pinctrl_add_gpio_range(pctldev, &pin_range->range);
1818 chip_dbg(gc, "created GPIO range %d->%d ==> %s PINGRP %s\n",
1819 gpio_offset, gpio_offset + pin_range->range.npins - 1,
1820 pinctrl_dev_get_devname(pctldev), pin_group);
1822 list_add_tail(&pin_range->node, &gdev->pin_ranges);
1826 EXPORT_SYMBOL_GPL(gpiochip_add_pingroup_range);
1829 * gpiochip_add_pin_range() - add a range for GPIO <-> pin mapping
1830 * @gc: the gpiochip to add the range for
1831 * @pinctl_name: the dev_name() of the pin controller to map to
1832 * @gpio_offset: the start offset in the current gpio_chip number space
1833 * @pin_offset: the start offset in the pin controller number space
1834 * @npins: the number of pins from the offset of each pin space (GPIO and
1835 * pin controller) to accumulate in this range
1838 * 0 on success, or a negative error-code on failure.
1840 * Calling this function directly from a DeviceTree-supported
1841 * pinctrl driver is DEPRECATED. Please see Section 2.1 of
1842 * Documentation/devicetree/bindings/gpio/gpio.txt on how to
1843 * bind pinctrl and gpio drivers via the "gpio-ranges" property.
1845 int gpiochip_add_pin_range(struct gpio_chip *gc, const char *pinctl_name,
1846 unsigned int gpio_offset, unsigned int pin_offset,
1849 struct gpio_pin_range *pin_range;
1850 struct gpio_device *gdev = gc->gpiodev;
1853 pin_range = kzalloc(sizeof(*pin_range), GFP_KERNEL);
1855 chip_err(gc, "failed to allocate pin ranges\n");
1859 /* Use local offset as range ID */
1860 pin_range->range.id = gpio_offset;
1861 pin_range->range.gc = gc;
1862 pin_range->range.name = gc->label;
1863 pin_range->range.base = gdev->base + gpio_offset;
1864 pin_range->range.pin_base = pin_offset;
1865 pin_range->range.npins = npins;
1866 pin_range->pctldev = pinctrl_find_and_add_gpio_range(pinctl_name,
1868 if (IS_ERR(pin_range->pctldev)) {
1869 ret = PTR_ERR(pin_range->pctldev);
1870 chip_err(gc, "could not create pin range\n");
1874 chip_dbg(gc, "created GPIO range %d->%d ==> %s PIN %d->%d\n",
1875 gpio_offset, gpio_offset + npins - 1,
1877 pin_offset, pin_offset + npins - 1);
1879 list_add_tail(&pin_range->node, &gdev->pin_ranges);
1883 EXPORT_SYMBOL_GPL(gpiochip_add_pin_range);
1886 * gpiochip_remove_pin_ranges() - remove all the GPIO <-> pin mappings
1887 * @gc: the chip to remove all the mappings for
1889 void gpiochip_remove_pin_ranges(struct gpio_chip *gc)
1891 struct gpio_pin_range *pin_range, *tmp;
1892 struct gpio_device *gdev = gc->gpiodev;
1894 list_for_each_entry_safe(pin_range, tmp, &gdev->pin_ranges, node) {
1895 list_del(&pin_range->node);
1896 pinctrl_remove_gpio_range(pin_range->pctldev,
1901 EXPORT_SYMBOL_GPL(gpiochip_remove_pin_ranges);
1903 #endif /* CONFIG_PINCTRL */
1905 /* These "optional" allocation calls help prevent drivers from stomping
1906 * on each other, and help provide better diagnostics in debugfs.
1907 * They're called even less than the "set direction" calls.
1909 static int gpiod_request_commit(struct gpio_desc *desc, const char *label)
1911 struct gpio_chip *gc = desc->gdev->chip;
1913 unsigned long flags;
1917 label = kstrdup_const(label, GFP_KERNEL);
1922 spin_lock_irqsave(&gpio_lock, flags);
1924 /* NOTE: gpio_request() can be called in early boot,
1925 * before IRQs are enabled, for non-sleeping (SOC) GPIOs.
1928 if (test_and_set_bit(FLAG_REQUESTED, &desc->flags) == 0) {
1929 desc_set_label(desc, label ? : "?");
1932 goto out_free_unlock;
1936 /* gc->request may sleep */
1937 spin_unlock_irqrestore(&gpio_lock, flags);
1938 offset = gpio_chip_hwgpio(desc);
1939 if (gpiochip_line_is_valid(gc, offset))
1940 ret = gc->request(gc, offset);
1943 spin_lock_irqsave(&gpio_lock, flags);
1946 desc_set_label(desc, NULL);
1947 clear_bit(FLAG_REQUESTED, &desc->flags);
1948 goto out_free_unlock;
1951 if (gc->get_direction) {
1952 /* gc->get_direction may sleep */
1953 spin_unlock_irqrestore(&gpio_lock, flags);
1954 gpiod_get_direction(desc);
1955 spin_lock_irqsave(&gpio_lock, flags);
1957 spin_unlock_irqrestore(&gpio_lock, flags);
1961 spin_unlock_irqrestore(&gpio_lock, flags);
1967 * This descriptor validation needs to be inserted verbatim into each
1968 * function taking a descriptor, so we need to use a preprocessor
1969 * macro to avoid endless duplication. If the desc is NULL it is an
1970 * optional GPIO and calls should just bail out.
1972 static int validate_desc(const struct gpio_desc *desc, const char *func)
1977 pr_warn("%s: invalid GPIO (errorpointer)\n", func);
1978 return PTR_ERR(desc);
1981 pr_warn("%s: invalid GPIO (no device)\n", func);
1984 if (!desc->gdev->chip) {
1985 dev_warn(&desc->gdev->dev,
1986 "%s: backing chip is gone\n", func);
1992 #define VALIDATE_DESC(desc) do { \
1993 int __valid = validate_desc(desc, __func__); \
1998 #define VALIDATE_DESC_VOID(desc) do { \
1999 int __valid = validate_desc(desc, __func__); \
2004 int gpiod_request(struct gpio_desc *desc, const char *label)
2006 int ret = -EPROBE_DEFER;
2007 struct gpio_device *gdev;
2009 VALIDATE_DESC(desc);
2012 if (try_module_get(gdev->owner)) {
2013 ret = gpiod_request_commit(desc, label);
2015 module_put(gdev->owner);
2017 get_device(&gdev->dev);
2021 gpiod_dbg(desc, "%s: status %d\n", __func__, ret);
2026 static bool gpiod_free_commit(struct gpio_desc *desc)
2029 unsigned long flags;
2030 struct gpio_chip *gc;
2034 gpiod_unexport(desc);
2036 spin_lock_irqsave(&gpio_lock, flags);
2038 gc = desc->gdev->chip;
2039 if (gc && test_bit(FLAG_REQUESTED, &desc->flags)) {
2041 spin_unlock_irqrestore(&gpio_lock, flags);
2042 might_sleep_if(gc->can_sleep);
2043 gc->free(gc, gpio_chip_hwgpio(desc));
2044 spin_lock_irqsave(&gpio_lock, flags);
2046 kfree_const(desc->label);
2047 desc_set_label(desc, NULL);
2048 clear_bit(FLAG_ACTIVE_LOW, &desc->flags);
2049 clear_bit(FLAG_REQUESTED, &desc->flags);
2050 clear_bit(FLAG_OPEN_DRAIN, &desc->flags);
2051 clear_bit(FLAG_OPEN_SOURCE, &desc->flags);
2052 clear_bit(FLAG_PULL_UP, &desc->flags);
2053 clear_bit(FLAG_PULL_DOWN, &desc->flags);
2054 clear_bit(FLAG_BIAS_DISABLE, &desc->flags);
2055 clear_bit(FLAG_EDGE_RISING, &desc->flags);
2056 clear_bit(FLAG_EDGE_FALLING, &desc->flags);
2057 clear_bit(FLAG_IS_HOGGED, &desc->flags);
2058 #ifdef CONFIG_OF_DYNAMIC
2061 #ifdef CONFIG_GPIO_CDEV
2062 WRITE_ONCE(desc->debounce_period_us, 0);
2067 spin_unlock_irqrestore(&gpio_lock, flags);
2068 blocking_notifier_call_chain(&desc->gdev->notifier,
2069 GPIOLINE_CHANGED_RELEASED, desc);
2074 void gpiod_free(struct gpio_desc *desc)
2076 if (desc && desc->gdev && gpiod_free_commit(desc)) {
2077 module_put(desc->gdev->owner);
2078 put_device(&desc->gdev->dev);
2080 WARN_ON(extra_checks);
2085 * gpiochip_is_requested - return string iff signal was requested
2086 * @gc: controller managing the signal
2087 * @offset: of signal within controller's 0..(ngpio - 1) range
2089 * Returns NULL if the GPIO is not currently requested, else a string.
2090 * The string returned is the label passed to gpio_request(); if none has been
2091 * passed it is a meaningless, non-NULL constant.
2093 * This function is for use by GPIO controller drivers. The label can
2094 * help with diagnostics, and knowing that the signal is used as a GPIO
2095 * can help avoid accidentally multiplexing it to another controller.
2097 const char *gpiochip_is_requested(struct gpio_chip *gc, unsigned int offset)
2099 struct gpio_desc *desc;
2101 desc = gpiochip_get_desc(gc, offset);
2105 if (test_bit(FLAG_REQUESTED, &desc->flags) == 0)
2109 EXPORT_SYMBOL_GPL(gpiochip_is_requested);
2112 * gpiochip_request_own_desc - Allow GPIO chip to request its own descriptor
2114 * @hwnum: hardware number of the GPIO for which to request the descriptor
2115 * @label: label for the GPIO
2116 * @lflags: lookup flags for this GPIO or 0 if default, this can be used to
2117 * specify things like line inversion semantics with the machine flags
2118 * such as GPIO_OUT_LOW
2119 * @dflags: descriptor request flags for this GPIO or 0 if default, this
2120 * can be used to specify consumer semantics such as open drain
2122 * Function allows GPIO chip drivers to request and use their own GPIO
2123 * descriptors via gpiolib API. Difference to gpiod_request() is that this
2124 * function will not increase reference count of the GPIO chip module. This
2125 * allows the GPIO chip module to be unloaded as needed (we assume that the
2126 * GPIO chip driver handles freeing the GPIOs it has requested).
2129 * A pointer to the GPIO descriptor, or an ERR_PTR()-encoded negative error
2132 struct gpio_desc *gpiochip_request_own_desc(struct gpio_chip *gc,
2135 enum gpio_lookup_flags lflags,
2136 enum gpiod_flags dflags)
2138 struct gpio_desc *desc = gpiochip_get_desc(gc, hwnum);
2142 chip_err(gc, "failed to get GPIO descriptor\n");
2146 ret = gpiod_request_commit(desc, label);
2148 return ERR_PTR(ret);
2150 ret = gpiod_configure_flags(desc, label, lflags, dflags);
2152 chip_err(gc, "setup of own GPIO %s failed\n", label);
2153 gpiod_free_commit(desc);
2154 return ERR_PTR(ret);
2159 EXPORT_SYMBOL_GPL(gpiochip_request_own_desc);
2162 * gpiochip_free_own_desc - Free GPIO requested by the chip driver
2163 * @desc: GPIO descriptor to free
2165 * Function frees the given GPIO requested previously with
2166 * gpiochip_request_own_desc().
2168 void gpiochip_free_own_desc(struct gpio_desc *desc)
2171 gpiod_free_commit(desc);
2173 EXPORT_SYMBOL_GPL(gpiochip_free_own_desc);
2176 * Drivers MUST set GPIO direction before making get/set calls. In
2177 * some cases this is done in early boot, before IRQs are enabled.
2179 * As a rule these aren't called more than once (except for drivers
2180 * using the open-drain emulation idiom) so these are natural places
2181 * to accumulate extra debugging checks. Note that we can't (yet)
2182 * rely on gpio_request() having been called beforehand.
2185 static int gpio_do_set_config(struct gpio_chip *gc, unsigned int offset,
2186 unsigned long config)
2188 if (!gc->set_config)
2191 return gc->set_config(gc, offset, config);
2194 static int gpio_set_config_with_argument(struct gpio_desc *desc,
2195 enum pin_config_param mode,
2198 struct gpio_chip *gc = desc->gdev->chip;
2199 unsigned long config;
2201 config = pinconf_to_config_packed(mode, argument);
2202 return gpio_do_set_config(gc, gpio_chip_hwgpio(desc), config);
2205 static int gpio_set_config_with_argument_optional(struct gpio_desc *desc,
2206 enum pin_config_param mode,
2209 struct device *dev = &desc->gdev->dev;
2210 int gpio = gpio_chip_hwgpio(desc);
2213 ret = gpio_set_config_with_argument(desc, mode, argument);
2214 if (ret != -ENOTSUPP)
2218 case PIN_CONFIG_PERSIST_STATE:
2219 dev_dbg(dev, "Persistence not supported for GPIO %d\n", gpio);
2228 static int gpio_set_config(struct gpio_desc *desc, enum pin_config_param mode)
2230 return gpio_set_config_with_argument(desc, mode, 0);
2233 static int gpio_set_bias(struct gpio_desc *desc)
2235 enum pin_config_param bias;
2238 if (test_bit(FLAG_BIAS_DISABLE, &desc->flags))
2239 bias = PIN_CONFIG_BIAS_DISABLE;
2240 else if (test_bit(FLAG_PULL_UP, &desc->flags))
2241 bias = PIN_CONFIG_BIAS_PULL_UP;
2242 else if (test_bit(FLAG_PULL_DOWN, &desc->flags))
2243 bias = PIN_CONFIG_BIAS_PULL_DOWN;
2248 case PIN_CONFIG_BIAS_PULL_DOWN:
2249 case PIN_CONFIG_BIAS_PULL_UP:
2258 return gpio_set_config_with_argument_optional(desc, bias, arg);
2262 * gpio_set_debounce_timeout() - Set debounce timeout
2263 * @desc: GPIO descriptor to set the debounce timeout
2264 * @debounce: Debounce timeout in microseconds
2266 * The function calls the certain GPIO driver to set debounce timeout
2269 * Returns 0 on success, or negative error code otherwise.
2271 int gpio_set_debounce_timeout(struct gpio_desc *desc, unsigned int debounce)
2273 return gpio_set_config_with_argument_optional(desc,
2274 PIN_CONFIG_INPUT_DEBOUNCE,
2279 * gpiod_direction_input - set the GPIO direction to input
2280 * @desc: GPIO to set to input
2282 * Set the direction of the passed GPIO to input, such as gpiod_get_value() can
2283 * be called safely on it.
2285 * Return 0 in case of success, else an error code.
2287 int gpiod_direction_input(struct gpio_desc *desc)
2289 struct gpio_chip *gc;
2292 VALIDATE_DESC(desc);
2293 gc = desc->gdev->chip;
2296 * It is legal to have no .get() and .direction_input() specified if
2297 * the chip is output-only, but you can't specify .direction_input()
2298 * and not support the .get() operation, that doesn't make sense.
2300 if (!gc->get && gc->direction_input) {
2302 "%s: missing get() but have direction_input()\n",
2308 * If we have a .direction_input() callback, things are simple,
2309 * just call it. Else we are some input-only chip so try to check the
2310 * direction (if .get_direction() is supported) else we silently
2311 * assume we are in input mode after this.
2313 if (gc->direction_input) {
2314 ret = gc->direction_input(gc, gpio_chip_hwgpio(desc));
2315 } else if (gc->get_direction &&
2316 (gc->get_direction(gc, gpio_chip_hwgpio(desc)) != 1)) {
2318 "%s: missing direction_input() operation and line is output\n",
2323 clear_bit(FLAG_IS_OUT, &desc->flags);
2324 ret = gpio_set_bias(desc);
2327 trace_gpio_direction(desc_to_gpio(desc), 1, ret);
2331 EXPORT_SYMBOL_GPL(gpiod_direction_input);
2333 static int gpiod_direction_output_raw_commit(struct gpio_desc *desc, int value)
2335 struct gpio_chip *gc = desc->gdev->chip;
2340 * It's OK not to specify .direction_output() if the gpiochip is
2341 * output-only, but if there is then not even a .set() operation it
2342 * is pretty tricky to drive the output line.
2344 if (!gc->set && !gc->direction_output) {
2346 "%s: missing set() and direction_output() operations\n",
2351 if (gc->direction_output) {
2352 ret = gc->direction_output(gc, gpio_chip_hwgpio(desc), val);
2354 /* Check that we are in output mode if we can */
2355 if (gc->get_direction &&
2356 gc->get_direction(gc, gpio_chip_hwgpio(desc))) {
2358 "%s: missing direction_output() operation\n",
2363 * If we can't actively set the direction, we are some
2364 * output-only chip, so just drive the output as desired.
2366 gc->set(gc, gpio_chip_hwgpio(desc), val);
2370 set_bit(FLAG_IS_OUT, &desc->flags);
2371 trace_gpio_value(desc_to_gpio(desc), 0, val);
2372 trace_gpio_direction(desc_to_gpio(desc), 0, ret);
2377 * gpiod_direction_output_raw - set the GPIO direction to output
2378 * @desc: GPIO to set to output
2379 * @value: initial output value of the GPIO
2381 * Set the direction of the passed GPIO to output, such as gpiod_set_value() can
2382 * be called safely on it. The initial value of the output must be specified
2383 * as raw value on the physical line without regard for the ACTIVE_LOW status.
2385 * Return 0 in case of success, else an error code.
2387 int gpiod_direction_output_raw(struct gpio_desc *desc, int value)
2389 VALIDATE_DESC(desc);
2390 return gpiod_direction_output_raw_commit(desc, value);
2392 EXPORT_SYMBOL_GPL(gpiod_direction_output_raw);
2395 * gpiod_direction_output - set the GPIO direction to output
2396 * @desc: GPIO to set to output
2397 * @value: initial output value of the GPIO
2399 * Set the direction of the passed GPIO to output, such as gpiod_set_value() can
2400 * be called safely on it. The initial value of the output must be specified
2401 * as the logical value of the GPIO, i.e. taking its ACTIVE_LOW status into
2404 * Return 0 in case of success, else an error code.
2406 int gpiod_direction_output(struct gpio_desc *desc, int value)
2410 VALIDATE_DESC(desc);
2411 if (test_bit(FLAG_ACTIVE_LOW, &desc->flags))
2416 /* GPIOs used for enabled IRQs shall not be set as output */
2417 if (test_bit(FLAG_USED_AS_IRQ, &desc->flags) &&
2418 test_bit(FLAG_IRQ_IS_ENABLED, &desc->flags)) {
2420 "%s: tried to set a GPIO tied to an IRQ as output\n",
2425 if (test_bit(FLAG_OPEN_DRAIN, &desc->flags)) {
2426 /* First see if we can enable open drain in hardware */
2427 ret = gpio_set_config(desc, PIN_CONFIG_DRIVE_OPEN_DRAIN);
2429 goto set_output_value;
2430 /* Emulate open drain by not actively driving the line high */
2432 ret = gpiod_direction_input(desc);
2433 goto set_output_flag;
2435 } else if (test_bit(FLAG_OPEN_SOURCE, &desc->flags)) {
2436 ret = gpio_set_config(desc, PIN_CONFIG_DRIVE_OPEN_SOURCE);
2438 goto set_output_value;
2439 /* Emulate open source by not actively driving the line low */
2441 ret = gpiod_direction_input(desc);
2442 goto set_output_flag;
2445 gpio_set_config(desc, PIN_CONFIG_DRIVE_PUSH_PULL);
2449 ret = gpio_set_bias(desc);
2452 return gpiod_direction_output_raw_commit(desc, value);
2456 * When emulating open-source or open-drain functionalities by not
2457 * actively driving the line (setting mode to input) we still need to
2458 * set the IS_OUT flag or otherwise we won't be able to set the line
2462 set_bit(FLAG_IS_OUT, &desc->flags);
2465 EXPORT_SYMBOL_GPL(gpiod_direction_output);
2468 * gpiod_enable_hw_timestamp_ns - Enable hardware timestamp in nanoseconds.
2470 * @desc: GPIO to enable.
2471 * @flags: Flags related to GPIO edge.
2473 * Return 0 in case of success, else negative error code.
2475 int gpiod_enable_hw_timestamp_ns(struct gpio_desc *desc, unsigned long flags)
2478 struct gpio_chip *gc;
2480 VALIDATE_DESC(desc);
2482 gc = desc->gdev->chip;
2483 if (!gc->en_hw_timestamp) {
2484 gpiod_warn(desc, "%s: hw ts not supported\n", __func__);
2488 ret = gc->en_hw_timestamp(gc, gpio_chip_hwgpio(desc), flags);
2490 gpiod_warn(desc, "%s: hw ts request failed\n", __func__);
2494 EXPORT_SYMBOL_GPL(gpiod_enable_hw_timestamp_ns);
2497 * gpiod_disable_hw_timestamp_ns - Disable hardware timestamp.
2499 * @desc: GPIO to disable.
2500 * @flags: Flags related to GPIO edge, same value as used during enable call.
2502 * Return 0 in case of success, else negative error code.
2504 int gpiod_disable_hw_timestamp_ns(struct gpio_desc *desc, unsigned long flags)
2507 struct gpio_chip *gc;
2509 VALIDATE_DESC(desc);
2511 gc = desc->gdev->chip;
2512 if (!gc->dis_hw_timestamp) {
2513 gpiod_warn(desc, "%s: hw ts not supported\n", __func__);
2517 ret = gc->dis_hw_timestamp(gc, gpio_chip_hwgpio(desc), flags);
2519 gpiod_warn(desc, "%s: hw ts release failed\n", __func__);
2523 EXPORT_SYMBOL_GPL(gpiod_disable_hw_timestamp_ns);
2526 * gpiod_set_config - sets @config for a GPIO
2527 * @desc: descriptor of the GPIO for which to set the configuration
2528 * @config: Same packed config format as generic pinconf
2531 * 0 on success, %-ENOTSUPP if the controller doesn't support setting the
2534 int gpiod_set_config(struct gpio_desc *desc, unsigned long config)
2536 struct gpio_chip *gc;
2538 VALIDATE_DESC(desc);
2539 gc = desc->gdev->chip;
2541 return gpio_do_set_config(gc, gpio_chip_hwgpio(desc), config);
2543 EXPORT_SYMBOL_GPL(gpiod_set_config);
2546 * gpiod_set_debounce - sets @debounce time for a GPIO
2547 * @desc: descriptor of the GPIO for which to set debounce time
2548 * @debounce: debounce time in microseconds
2551 * 0 on success, %-ENOTSUPP if the controller doesn't support setting the
2554 int gpiod_set_debounce(struct gpio_desc *desc, unsigned int debounce)
2556 unsigned long config;
2558 config = pinconf_to_config_packed(PIN_CONFIG_INPUT_DEBOUNCE, debounce);
2559 return gpiod_set_config(desc, config);
2561 EXPORT_SYMBOL_GPL(gpiod_set_debounce);
2564 * gpiod_set_transitory - Lose or retain GPIO state on suspend or reset
2565 * @desc: descriptor of the GPIO for which to configure persistence
2566 * @transitory: True to lose state on suspend or reset, false for persistence
2569 * 0 on success, otherwise a negative error code.
2571 int gpiod_set_transitory(struct gpio_desc *desc, bool transitory)
2573 VALIDATE_DESC(desc);
2575 * Handle FLAG_TRANSITORY first, enabling queries to gpiolib for
2576 * persistence state.
2578 assign_bit(FLAG_TRANSITORY, &desc->flags, transitory);
2580 /* If the driver supports it, set the persistence state now */
2581 return gpio_set_config_with_argument_optional(desc,
2582 PIN_CONFIG_PERSIST_STATE,
2585 EXPORT_SYMBOL_GPL(gpiod_set_transitory);
2588 * gpiod_is_active_low - test whether a GPIO is active-low or not
2589 * @desc: the gpio descriptor to test
2591 * Returns 1 if the GPIO is active-low, 0 otherwise.
2593 int gpiod_is_active_low(const struct gpio_desc *desc)
2595 VALIDATE_DESC(desc);
2596 return test_bit(FLAG_ACTIVE_LOW, &desc->flags);
2598 EXPORT_SYMBOL_GPL(gpiod_is_active_low);
2601 * gpiod_toggle_active_low - toggle whether a GPIO is active-low or not
2602 * @desc: the gpio descriptor to change
2604 void gpiod_toggle_active_low(struct gpio_desc *desc)
2606 VALIDATE_DESC_VOID(desc);
2607 change_bit(FLAG_ACTIVE_LOW, &desc->flags);
2609 EXPORT_SYMBOL_GPL(gpiod_toggle_active_low);
2611 static int gpio_chip_get_value(struct gpio_chip *gc, const struct gpio_desc *desc)
2613 return gc->get ? gc->get(gc, gpio_chip_hwgpio(desc)) : -EIO;
2616 /* I/O calls are only valid after configuration completed; the relevant
2617 * "is this a valid GPIO" error checks should already have been done.
2619 * "Get" operations are often inlinable as reading a pin value register,
2620 * and masking the relevant bit in that register.
2622 * When "set" operations are inlinable, they involve writing that mask to
2623 * one register to set a low value, or a different register to set it high.
2624 * Otherwise locking is needed, so there may be little value to inlining.
2626 *------------------------------------------------------------------------
2628 * IMPORTANT!!! The hot paths -- get/set value -- assume that callers
2629 * have requested the GPIO. That can include implicit requesting by
2630 * a direction setting call. Marking a gpio as requested locks its chip
2631 * in memory, guaranteeing that these table lookups need no more locking
2632 * and that gpiochip_remove() will fail.
2634 * REVISIT when debugging, consider adding some instrumentation to ensure
2635 * that the GPIO was actually requested.
2638 static int gpiod_get_raw_value_commit(const struct gpio_desc *desc)
2640 struct gpio_chip *gc;
2643 gc = desc->gdev->chip;
2644 value = gpio_chip_get_value(gc, desc);
2645 value = value < 0 ? value : !!value;
2646 trace_gpio_value(desc_to_gpio(desc), 1, value);
2650 static int gpio_chip_get_multiple(struct gpio_chip *gc,
2651 unsigned long *mask, unsigned long *bits)
2653 if (gc->get_multiple)
2654 return gc->get_multiple(gc, mask, bits);
2658 for_each_set_bit(i, mask, gc->ngpio) {
2659 value = gc->get(gc, i);
2662 __assign_bit(i, bits, value);
2669 int gpiod_get_array_value_complex(bool raw, bool can_sleep,
2670 unsigned int array_size,
2671 struct gpio_desc **desc_array,
2672 struct gpio_array *array_info,
2673 unsigned long *value_bitmap)
2678 * Validate array_info against desc_array and its size.
2679 * It should immediately follow desc_array if both
2680 * have been obtained from the same gpiod_get_array() call.
2682 if (array_info && array_info->desc == desc_array &&
2683 array_size <= array_info->size &&
2684 (void *)array_info == desc_array + array_info->size) {
2686 WARN_ON(array_info->chip->can_sleep);
2688 ret = gpio_chip_get_multiple(array_info->chip,
2689 array_info->get_mask,
2694 if (!raw && !bitmap_empty(array_info->invert_mask, array_size))
2695 bitmap_xor(value_bitmap, value_bitmap,
2696 array_info->invert_mask, array_size);
2698 i = find_first_zero_bit(array_info->get_mask, array_size);
2699 if (i == array_size)
2705 while (i < array_size) {
2706 struct gpio_chip *gc = desc_array[i]->gdev->chip;
2707 DECLARE_BITMAP(fastpath_mask, FASTPATH_NGPIO);
2708 DECLARE_BITMAP(fastpath_bits, FASTPATH_NGPIO);
2709 unsigned long *mask, *bits;
2712 if (likely(gc->ngpio <= FASTPATH_NGPIO)) {
2713 mask = fastpath_mask;
2714 bits = fastpath_bits;
2716 gfp_t flags = can_sleep ? GFP_KERNEL : GFP_ATOMIC;
2718 mask = bitmap_alloc(gc->ngpio, flags);
2722 bits = bitmap_alloc(gc->ngpio, flags);
2729 bitmap_zero(mask, gc->ngpio);
2732 WARN_ON(gc->can_sleep);
2734 /* collect all inputs belonging to the same chip */
2737 const struct gpio_desc *desc = desc_array[i];
2738 int hwgpio = gpio_chip_hwgpio(desc);
2740 __set_bit(hwgpio, mask);
2744 i = find_next_zero_bit(array_info->get_mask,
2746 } while ((i < array_size) &&
2747 (desc_array[i]->gdev->chip == gc));
2749 ret = gpio_chip_get_multiple(gc, mask, bits);
2751 if (mask != fastpath_mask)
2753 if (bits != fastpath_bits)
2758 for (j = first; j < i; ) {
2759 const struct gpio_desc *desc = desc_array[j];
2760 int hwgpio = gpio_chip_hwgpio(desc);
2761 int value = test_bit(hwgpio, bits);
2763 if (!raw && test_bit(FLAG_ACTIVE_LOW, &desc->flags))
2765 __assign_bit(j, value_bitmap, value);
2766 trace_gpio_value(desc_to_gpio(desc), 1, value);
2770 j = find_next_zero_bit(array_info->get_mask, i,
2774 if (mask != fastpath_mask)
2776 if (bits != fastpath_bits)
2783 * gpiod_get_raw_value() - return a gpio's raw value
2784 * @desc: gpio whose value will be returned
2786 * Return the GPIO's raw value, i.e. the value of the physical line disregarding
2787 * its ACTIVE_LOW status, or negative errno on failure.
2789 * This function can be called from contexts where we cannot sleep, and will
2790 * complain if the GPIO chip functions potentially sleep.
2792 int gpiod_get_raw_value(const struct gpio_desc *desc)
2794 VALIDATE_DESC(desc);
2795 /* Should be using gpiod_get_raw_value_cansleep() */
2796 WARN_ON(desc->gdev->chip->can_sleep);
2797 return gpiod_get_raw_value_commit(desc);
2799 EXPORT_SYMBOL_GPL(gpiod_get_raw_value);
2802 * gpiod_get_value() - return a gpio's value
2803 * @desc: gpio whose value will be returned
2805 * Return the GPIO's logical value, i.e. taking the ACTIVE_LOW status into
2806 * account, or negative errno on failure.
2808 * This function can be called from contexts where we cannot sleep, and will
2809 * complain if the GPIO chip functions potentially sleep.
2811 int gpiod_get_value(const struct gpio_desc *desc)
2815 VALIDATE_DESC(desc);
2816 /* Should be using gpiod_get_value_cansleep() */
2817 WARN_ON(desc->gdev->chip->can_sleep);
2819 value = gpiod_get_raw_value_commit(desc);
2823 if (test_bit(FLAG_ACTIVE_LOW, &desc->flags))
2828 EXPORT_SYMBOL_GPL(gpiod_get_value);
2831 * gpiod_get_raw_array_value() - read raw values from an array of GPIOs
2832 * @array_size: number of elements in the descriptor array / value bitmap
2833 * @desc_array: array of GPIO descriptors whose values will be read
2834 * @array_info: information on applicability of fast bitmap processing path
2835 * @value_bitmap: bitmap to store the read values
2837 * Read the raw values of the GPIOs, i.e. the values of the physical lines
2838 * without regard for their ACTIVE_LOW status. Return 0 in case of success,
2839 * else an error code.
2841 * This function can be called from contexts where we cannot sleep,
2842 * and it will complain if the GPIO chip functions potentially sleep.
2844 int gpiod_get_raw_array_value(unsigned int array_size,
2845 struct gpio_desc **desc_array,
2846 struct gpio_array *array_info,
2847 unsigned long *value_bitmap)
2851 return gpiod_get_array_value_complex(true, false, array_size,
2852 desc_array, array_info,
2855 EXPORT_SYMBOL_GPL(gpiod_get_raw_array_value);
2858 * gpiod_get_array_value() - read values from an array of GPIOs
2859 * @array_size: number of elements in the descriptor array / value bitmap
2860 * @desc_array: array of GPIO descriptors whose values will be read
2861 * @array_info: information on applicability of fast bitmap processing path
2862 * @value_bitmap: bitmap to store the read values
2864 * Read the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status
2865 * into account. Return 0 in case of success, else an error code.
2867 * This function can be called from contexts where we cannot sleep,
2868 * and it will complain if the GPIO chip functions potentially sleep.
2870 int gpiod_get_array_value(unsigned int array_size,
2871 struct gpio_desc **desc_array,
2872 struct gpio_array *array_info,
2873 unsigned long *value_bitmap)
2877 return gpiod_get_array_value_complex(false, false, array_size,
2878 desc_array, array_info,
2881 EXPORT_SYMBOL_GPL(gpiod_get_array_value);
2884 * gpio_set_open_drain_value_commit() - Set the open drain gpio's value.
2885 * @desc: gpio descriptor whose state need to be set.
2886 * @value: Non-zero for setting it HIGH otherwise it will set to LOW.
2888 static void gpio_set_open_drain_value_commit(struct gpio_desc *desc, bool value)
2891 struct gpio_chip *gc = desc->gdev->chip;
2892 int offset = gpio_chip_hwgpio(desc);
2895 ret = gc->direction_input(gc, offset);
2897 ret = gc->direction_output(gc, offset, 0);
2899 set_bit(FLAG_IS_OUT, &desc->flags);
2901 trace_gpio_direction(desc_to_gpio(desc), value, ret);
2904 "%s: Error in set_value for open drain err %d\n",
2909 * _gpio_set_open_source_value() - Set the open source gpio's value.
2910 * @desc: gpio descriptor whose state need to be set.
2911 * @value: Non-zero for setting it HIGH otherwise it will set to LOW.
2913 static void gpio_set_open_source_value_commit(struct gpio_desc *desc, bool value)
2916 struct gpio_chip *gc = desc->gdev->chip;
2917 int offset = gpio_chip_hwgpio(desc);
2920 ret = gc->direction_output(gc, offset, 1);
2922 set_bit(FLAG_IS_OUT, &desc->flags);
2924 ret = gc->direction_input(gc, offset);
2926 trace_gpio_direction(desc_to_gpio(desc), !value, ret);
2929 "%s: Error in set_value for open source err %d\n",
2933 static void gpiod_set_raw_value_commit(struct gpio_desc *desc, bool value)
2935 struct gpio_chip *gc;
2937 gc = desc->gdev->chip;
2938 trace_gpio_value(desc_to_gpio(desc), 0, value);
2939 gc->set(gc, gpio_chip_hwgpio(desc), value);
2943 * set multiple outputs on the same chip;
2944 * use the chip's set_multiple function if available;
2945 * otherwise set the outputs sequentially;
2946 * @chip: the GPIO chip we operate on
2947 * @mask: bit mask array; one bit per output; BITS_PER_LONG bits per word
2948 * defines which outputs are to be changed
2949 * @bits: bit value array; one bit per output; BITS_PER_LONG bits per word
2950 * defines the values the outputs specified by mask are to be set to
2952 static void gpio_chip_set_multiple(struct gpio_chip *gc,
2953 unsigned long *mask, unsigned long *bits)
2955 if (gc->set_multiple) {
2956 gc->set_multiple(gc, mask, bits);
2960 /* set outputs if the corresponding mask bit is set */
2961 for_each_set_bit(i, mask, gc->ngpio)
2962 gc->set(gc, i, test_bit(i, bits));
2966 int gpiod_set_array_value_complex(bool raw, bool can_sleep,
2967 unsigned int array_size,
2968 struct gpio_desc **desc_array,
2969 struct gpio_array *array_info,
2970 unsigned long *value_bitmap)
2975 * Validate array_info against desc_array and its size.
2976 * It should immediately follow desc_array if both
2977 * have been obtained from the same gpiod_get_array() call.
2979 if (array_info && array_info->desc == desc_array &&
2980 array_size <= array_info->size &&
2981 (void *)array_info == desc_array + array_info->size) {
2983 WARN_ON(array_info->chip->can_sleep);
2985 if (!raw && !bitmap_empty(array_info->invert_mask, array_size))
2986 bitmap_xor(value_bitmap, value_bitmap,
2987 array_info->invert_mask, array_size);
2989 gpio_chip_set_multiple(array_info->chip, array_info->set_mask,
2992 i = find_first_zero_bit(array_info->set_mask, array_size);
2993 if (i == array_size)
2999 while (i < array_size) {
3000 struct gpio_chip *gc = desc_array[i]->gdev->chip;
3001 DECLARE_BITMAP(fastpath_mask, FASTPATH_NGPIO);
3002 DECLARE_BITMAP(fastpath_bits, FASTPATH_NGPIO);
3003 unsigned long *mask, *bits;
3006 if (likely(gc->ngpio <= FASTPATH_NGPIO)) {
3007 mask = fastpath_mask;
3008 bits = fastpath_bits;
3010 gfp_t flags = can_sleep ? GFP_KERNEL : GFP_ATOMIC;
3012 mask = bitmap_alloc(gc->ngpio, flags);
3016 bits = bitmap_alloc(gc->ngpio, flags);
3023 bitmap_zero(mask, gc->ngpio);
3026 WARN_ON(gc->can_sleep);
3029 struct gpio_desc *desc = desc_array[i];
3030 int hwgpio = gpio_chip_hwgpio(desc);
3031 int value = test_bit(i, value_bitmap);
3034 * Pins applicable for fast input but not for
3035 * fast output processing may have been already
3036 * inverted inside the fast path, skip them.
3038 if (!raw && !(array_info &&
3039 test_bit(i, array_info->invert_mask)) &&
3040 test_bit(FLAG_ACTIVE_LOW, &desc->flags))
3042 trace_gpio_value(desc_to_gpio(desc), 0, value);
3044 * collect all normal outputs belonging to the same chip
3045 * open drain and open source outputs are set individually
3047 if (test_bit(FLAG_OPEN_DRAIN, &desc->flags) && !raw) {
3048 gpio_set_open_drain_value_commit(desc, value);
3049 } else if (test_bit(FLAG_OPEN_SOURCE, &desc->flags) && !raw) {
3050 gpio_set_open_source_value_commit(desc, value);
3052 __set_bit(hwgpio, mask);
3053 __assign_bit(hwgpio, bits, value);
3059 i = find_next_zero_bit(array_info->set_mask,
3061 } while ((i < array_size) &&
3062 (desc_array[i]->gdev->chip == gc));
3063 /* push collected bits to outputs */
3065 gpio_chip_set_multiple(gc, mask, bits);
3067 if (mask != fastpath_mask)
3069 if (bits != fastpath_bits)
3076 * gpiod_set_raw_value() - assign a gpio's raw value
3077 * @desc: gpio whose value will be assigned
3078 * @value: value to assign
3080 * Set the raw value of the GPIO, i.e. the value of its physical line without
3081 * regard for its ACTIVE_LOW status.
3083 * This function can be called from contexts where we cannot sleep, and will
3084 * complain if the GPIO chip functions potentially sleep.
3086 void gpiod_set_raw_value(struct gpio_desc *desc, int value)
3088 VALIDATE_DESC_VOID(desc);
3089 /* Should be using gpiod_set_raw_value_cansleep() */
3090 WARN_ON(desc->gdev->chip->can_sleep);
3091 gpiod_set_raw_value_commit(desc, value);
3093 EXPORT_SYMBOL_GPL(gpiod_set_raw_value);
3096 * gpiod_set_value_nocheck() - set a GPIO line value without checking
3097 * @desc: the descriptor to set the value on
3098 * @value: value to set
3100 * This sets the value of a GPIO line backing a descriptor, applying
3101 * different semantic quirks like active low and open drain/source
3104 static void gpiod_set_value_nocheck(struct gpio_desc *desc, int value)
3106 if (test_bit(FLAG_ACTIVE_LOW, &desc->flags))
3108 if (test_bit(FLAG_OPEN_DRAIN, &desc->flags))
3109 gpio_set_open_drain_value_commit(desc, value);
3110 else if (test_bit(FLAG_OPEN_SOURCE, &desc->flags))
3111 gpio_set_open_source_value_commit(desc, value);
3113 gpiod_set_raw_value_commit(desc, value);
3117 * gpiod_set_value() - assign a gpio's value
3118 * @desc: gpio whose value will be assigned
3119 * @value: value to assign
3121 * Set the logical value of the GPIO, i.e. taking its ACTIVE_LOW,
3122 * OPEN_DRAIN and OPEN_SOURCE flags into account.
3124 * This function can be called from contexts where we cannot sleep, and will
3125 * complain if the GPIO chip functions potentially sleep.
3127 void gpiod_set_value(struct gpio_desc *desc, int value)
3129 VALIDATE_DESC_VOID(desc);
3130 /* Should be using gpiod_set_value_cansleep() */
3131 WARN_ON(desc->gdev->chip->can_sleep);
3132 gpiod_set_value_nocheck(desc, value);
3134 EXPORT_SYMBOL_GPL(gpiod_set_value);
3137 * gpiod_set_raw_array_value() - assign values to an array of GPIOs
3138 * @array_size: number of elements in the descriptor array / value bitmap
3139 * @desc_array: array of GPIO descriptors whose values will be assigned
3140 * @array_info: information on applicability of fast bitmap processing path
3141 * @value_bitmap: bitmap of values to assign
3143 * Set the raw values of the GPIOs, i.e. the values of the physical lines
3144 * without regard for their ACTIVE_LOW status.
3146 * This function can be called from contexts where we cannot sleep, and will
3147 * complain if the GPIO chip functions potentially sleep.
3149 int gpiod_set_raw_array_value(unsigned int array_size,
3150 struct gpio_desc **desc_array,
3151 struct gpio_array *array_info,
3152 unsigned long *value_bitmap)
3156 return gpiod_set_array_value_complex(true, false, array_size,
3157 desc_array, array_info, value_bitmap);
3159 EXPORT_SYMBOL_GPL(gpiod_set_raw_array_value);
3162 * gpiod_set_array_value() - assign values to an array of GPIOs
3163 * @array_size: number of elements in the descriptor array / value bitmap
3164 * @desc_array: array of GPIO descriptors whose values will be assigned
3165 * @array_info: information on applicability of fast bitmap processing path
3166 * @value_bitmap: bitmap of values to assign
3168 * Set the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status
3171 * This function can be called from contexts where we cannot sleep, and will
3172 * complain if the GPIO chip functions potentially sleep.
3174 int gpiod_set_array_value(unsigned int array_size,
3175 struct gpio_desc **desc_array,
3176 struct gpio_array *array_info,
3177 unsigned long *value_bitmap)
3181 return gpiod_set_array_value_complex(false, false, array_size,
3182 desc_array, array_info,
3185 EXPORT_SYMBOL_GPL(gpiod_set_array_value);
3188 * gpiod_cansleep() - report whether gpio value access may sleep
3189 * @desc: gpio to check
3192 int gpiod_cansleep(const struct gpio_desc *desc)
3194 VALIDATE_DESC(desc);
3195 return desc->gdev->chip->can_sleep;
3197 EXPORT_SYMBOL_GPL(gpiod_cansleep);
3200 * gpiod_set_consumer_name() - set the consumer name for the descriptor
3201 * @desc: gpio to set the consumer name on
3202 * @name: the new consumer name
3204 int gpiod_set_consumer_name(struct gpio_desc *desc, const char *name)
3206 VALIDATE_DESC(desc);
3208 name = kstrdup_const(name, GFP_KERNEL);
3213 kfree_const(desc->label);
3214 desc_set_label(desc, name);
3218 EXPORT_SYMBOL_GPL(gpiod_set_consumer_name);
3221 * gpiod_to_irq() - return the IRQ corresponding to a GPIO
3222 * @desc: gpio whose IRQ will be returned (already requested)
3224 * Return the IRQ corresponding to the passed GPIO, or an error code in case of
3227 int gpiod_to_irq(const struct gpio_desc *desc)
3229 struct gpio_chip *gc;
3233 * Cannot VALIDATE_DESC() here as gpiod_to_irq() consumer semantics
3234 * requires this function to not return zero on an invalid descriptor
3235 * but rather a negative error number.
3237 if (!desc || IS_ERR(desc) || !desc->gdev || !desc->gdev->chip)
3240 gc = desc->gdev->chip;
3241 offset = gpio_chip_hwgpio(desc);
3243 int retirq = gc->to_irq(gc, offset);
3245 /* Zero means NO_IRQ */
3251 #ifdef CONFIG_GPIOLIB_IRQCHIP
3254 * Avoid race condition with other code, which tries to lookup
3255 * an IRQ before the irqchip has been properly registered,
3256 * i.e. while gpiochip is still being brought up.
3258 return -EPROBE_DEFER;
3263 EXPORT_SYMBOL_GPL(gpiod_to_irq);
3266 * gpiochip_lock_as_irq() - lock a GPIO to be used as IRQ
3267 * @gc: the chip the GPIO to lock belongs to
3268 * @offset: the offset of the GPIO to lock as IRQ
3270 * This is used directly by GPIO drivers that want to lock down
3271 * a certain GPIO line to be used for IRQs.
3273 int gpiochip_lock_as_irq(struct gpio_chip *gc, unsigned int offset)
3275 struct gpio_desc *desc;
3277 desc = gpiochip_get_desc(gc, offset);
3279 return PTR_ERR(desc);
3282 * If it's fast: flush the direction setting if something changed
3285 if (!gc->can_sleep && gc->get_direction) {
3286 int dir = gpiod_get_direction(desc);
3289 chip_err(gc, "%s: cannot get GPIO direction\n",
3295 /* To be valid for IRQ the line needs to be input or open drain */
3296 if (test_bit(FLAG_IS_OUT, &desc->flags) &&
3297 !test_bit(FLAG_OPEN_DRAIN, &desc->flags)) {
3299 "%s: tried to flag a GPIO set as output for IRQ\n",
3304 set_bit(FLAG_USED_AS_IRQ, &desc->flags);
3305 set_bit(FLAG_IRQ_IS_ENABLED, &desc->flags);
3308 * If the consumer has not set up a label (such as when the
3309 * IRQ is referenced from .to_irq()) we set up a label here
3310 * so it is clear this is used as an interrupt.
3313 desc_set_label(desc, "interrupt");
3317 EXPORT_SYMBOL_GPL(gpiochip_lock_as_irq);
3320 * gpiochip_unlock_as_irq() - unlock a GPIO used as IRQ
3321 * @gc: the chip the GPIO to lock belongs to
3322 * @offset: the offset of the GPIO to lock as IRQ
3324 * This is used directly by GPIO drivers that want to indicate
3325 * that a certain GPIO is no longer used exclusively for IRQ.
3327 void gpiochip_unlock_as_irq(struct gpio_chip *gc, unsigned int offset)
3329 struct gpio_desc *desc;
3331 desc = gpiochip_get_desc(gc, offset);
3335 clear_bit(FLAG_USED_AS_IRQ, &desc->flags);
3336 clear_bit(FLAG_IRQ_IS_ENABLED, &desc->flags);
3338 /* If we only had this marking, erase it */
3339 if (desc->label && !strcmp(desc->label, "interrupt"))
3340 desc_set_label(desc, NULL);
3342 EXPORT_SYMBOL_GPL(gpiochip_unlock_as_irq);
3344 void gpiochip_disable_irq(struct gpio_chip *gc, unsigned int offset)
3346 struct gpio_desc *desc = gpiochip_get_desc(gc, offset);
3348 if (!IS_ERR(desc) &&
3349 !WARN_ON(!test_bit(FLAG_USED_AS_IRQ, &desc->flags)))
3350 clear_bit(FLAG_IRQ_IS_ENABLED, &desc->flags);
3352 EXPORT_SYMBOL_GPL(gpiochip_disable_irq);
3354 void gpiochip_enable_irq(struct gpio_chip *gc, unsigned int offset)
3356 struct gpio_desc *desc = gpiochip_get_desc(gc, offset);
3358 if (!IS_ERR(desc) &&
3359 !WARN_ON(!test_bit(FLAG_USED_AS_IRQ, &desc->flags))) {
3361 * We must not be output when using IRQ UNLESS we are
3364 WARN_ON(test_bit(FLAG_IS_OUT, &desc->flags) &&
3365 !test_bit(FLAG_OPEN_DRAIN, &desc->flags));
3366 set_bit(FLAG_IRQ_IS_ENABLED, &desc->flags);
3369 EXPORT_SYMBOL_GPL(gpiochip_enable_irq);
3371 bool gpiochip_line_is_irq(struct gpio_chip *gc, unsigned int offset)
3373 if (offset >= gc->ngpio)
3376 return test_bit(FLAG_USED_AS_IRQ, &gc->gpiodev->descs[offset].flags);
3378 EXPORT_SYMBOL_GPL(gpiochip_line_is_irq);
3380 int gpiochip_reqres_irq(struct gpio_chip *gc, unsigned int offset)
3384 if (!try_module_get(gc->gpiodev->owner))
3387 ret = gpiochip_lock_as_irq(gc, offset);
3389 chip_err(gc, "unable to lock HW IRQ %u for IRQ\n", offset);
3390 module_put(gc->gpiodev->owner);
3395 EXPORT_SYMBOL_GPL(gpiochip_reqres_irq);
3397 void gpiochip_relres_irq(struct gpio_chip *gc, unsigned int offset)
3399 gpiochip_unlock_as_irq(gc, offset);
3400 module_put(gc->gpiodev->owner);
3402 EXPORT_SYMBOL_GPL(gpiochip_relres_irq);
3404 bool gpiochip_line_is_open_drain(struct gpio_chip *gc, unsigned int offset)
3406 if (offset >= gc->ngpio)
3409 return test_bit(FLAG_OPEN_DRAIN, &gc->gpiodev->descs[offset].flags);
3411 EXPORT_SYMBOL_GPL(gpiochip_line_is_open_drain);
3413 bool gpiochip_line_is_open_source(struct gpio_chip *gc, unsigned int offset)
3415 if (offset >= gc->ngpio)
3418 return test_bit(FLAG_OPEN_SOURCE, &gc->gpiodev->descs[offset].flags);
3420 EXPORT_SYMBOL_GPL(gpiochip_line_is_open_source);
3422 bool gpiochip_line_is_persistent(struct gpio_chip *gc, unsigned int offset)
3424 if (offset >= gc->ngpio)
3427 return !test_bit(FLAG_TRANSITORY, &gc->gpiodev->descs[offset].flags);
3429 EXPORT_SYMBOL_GPL(gpiochip_line_is_persistent);
3432 * gpiod_get_raw_value_cansleep() - return a gpio's raw value
3433 * @desc: gpio whose value will be returned
3435 * Return the GPIO's raw value, i.e. the value of the physical line disregarding
3436 * its ACTIVE_LOW status, or negative errno on failure.
3438 * This function is to be called from contexts that can sleep.
3440 int gpiod_get_raw_value_cansleep(const struct gpio_desc *desc)
3442 might_sleep_if(extra_checks);
3443 VALIDATE_DESC(desc);
3444 return gpiod_get_raw_value_commit(desc);
3446 EXPORT_SYMBOL_GPL(gpiod_get_raw_value_cansleep);
3449 * gpiod_get_value_cansleep() - return a gpio's value
3450 * @desc: gpio whose value will be returned
3452 * Return the GPIO's logical value, i.e. taking the ACTIVE_LOW status into
3453 * account, or negative errno on failure.
3455 * This function is to be called from contexts that can sleep.
3457 int gpiod_get_value_cansleep(const struct gpio_desc *desc)
3461 might_sleep_if(extra_checks);
3462 VALIDATE_DESC(desc);
3463 value = gpiod_get_raw_value_commit(desc);
3467 if (test_bit(FLAG_ACTIVE_LOW, &desc->flags))
3472 EXPORT_SYMBOL_GPL(gpiod_get_value_cansleep);
3475 * gpiod_get_raw_array_value_cansleep() - read raw values from an array of GPIOs
3476 * @array_size: number of elements in the descriptor array / value bitmap
3477 * @desc_array: array of GPIO descriptors whose values will be read
3478 * @array_info: information on applicability of fast bitmap processing path
3479 * @value_bitmap: bitmap to store the read values
3481 * Read the raw values of the GPIOs, i.e. the values of the physical lines
3482 * without regard for their ACTIVE_LOW status. Return 0 in case of success,
3483 * else an error code.
3485 * This function is to be called from contexts that can sleep.
3487 int gpiod_get_raw_array_value_cansleep(unsigned int array_size,
3488 struct gpio_desc **desc_array,
3489 struct gpio_array *array_info,
3490 unsigned long *value_bitmap)
3492 might_sleep_if(extra_checks);
3495 return gpiod_get_array_value_complex(true, true, array_size,
3496 desc_array, array_info,
3499 EXPORT_SYMBOL_GPL(gpiod_get_raw_array_value_cansleep);
3502 * gpiod_get_array_value_cansleep() - read values from an array of GPIOs
3503 * @array_size: number of elements in the descriptor array / value bitmap
3504 * @desc_array: array of GPIO descriptors whose values will be read
3505 * @array_info: information on applicability of fast bitmap processing path
3506 * @value_bitmap: bitmap to store the read values
3508 * Read the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status
3509 * into account. Return 0 in case of success, else an error code.
3511 * This function is to be called from contexts that can sleep.
3513 int gpiod_get_array_value_cansleep(unsigned int array_size,
3514 struct gpio_desc **desc_array,
3515 struct gpio_array *array_info,
3516 unsigned long *value_bitmap)
3518 might_sleep_if(extra_checks);
3521 return gpiod_get_array_value_complex(false, true, array_size,
3522 desc_array, array_info,
3525 EXPORT_SYMBOL_GPL(gpiod_get_array_value_cansleep);
3528 * gpiod_set_raw_value_cansleep() - assign a gpio's raw value
3529 * @desc: gpio whose value will be assigned
3530 * @value: value to assign
3532 * Set the raw value of the GPIO, i.e. the value of its physical line without
3533 * regard for its ACTIVE_LOW status.
3535 * This function is to be called from contexts that can sleep.
3537 void gpiod_set_raw_value_cansleep(struct gpio_desc *desc, int value)
3539 might_sleep_if(extra_checks);
3540 VALIDATE_DESC_VOID(desc);
3541 gpiod_set_raw_value_commit(desc, value);
3543 EXPORT_SYMBOL_GPL(gpiod_set_raw_value_cansleep);
3546 * gpiod_set_value_cansleep() - assign a gpio's value
3547 * @desc: gpio whose value will be assigned
3548 * @value: value to assign
3550 * Set the logical value of the GPIO, i.e. taking its ACTIVE_LOW status into
3553 * This function is to be called from contexts that can sleep.
3555 void gpiod_set_value_cansleep(struct gpio_desc *desc, int value)
3557 might_sleep_if(extra_checks);
3558 VALIDATE_DESC_VOID(desc);
3559 gpiod_set_value_nocheck(desc, value);
3561 EXPORT_SYMBOL_GPL(gpiod_set_value_cansleep);
3564 * gpiod_set_raw_array_value_cansleep() - assign values to an array of GPIOs
3565 * @array_size: number of elements in the descriptor array / value bitmap
3566 * @desc_array: array of GPIO descriptors whose values will be assigned
3567 * @array_info: information on applicability of fast bitmap processing path
3568 * @value_bitmap: bitmap of values to assign
3570 * Set the raw values of the GPIOs, i.e. the values of the physical lines
3571 * without regard for their ACTIVE_LOW status.
3573 * This function is to be called from contexts that can sleep.
3575 int gpiod_set_raw_array_value_cansleep(unsigned int array_size,
3576 struct gpio_desc **desc_array,
3577 struct gpio_array *array_info,
3578 unsigned long *value_bitmap)
3580 might_sleep_if(extra_checks);
3583 return gpiod_set_array_value_complex(true, true, array_size, desc_array,
3584 array_info, value_bitmap);
3586 EXPORT_SYMBOL_GPL(gpiod_set_raw_array_value_cansleep);
3589 * gpiod_add_lookup_tables() - register GPIO device consumers
3590 * @tables: list of tables of consumers to register
3591 * @n: number of tables in the list
3593 void gpiod_add_lookup_tables(struct gpiod_lookup_table **tables, size_t n)
3597 mutex_lock(&gpio_lookup_lock);
3599 for (i = 0; i < n; i++)
3600 list_add_tail(&tables[i]->list, &gpio_lookup_list);
3602 mutex_unlock(&gpio_lookup_lock);
3606 * gpiod_set_array_value_cansleep() - assign values to an array of GPIOs
3607 * @array_size: number of elements in the descriptor array / value bitmap
3608 * @desc_array: array of GPIO descriptors whose values will be assigned
3609 * @array_info: information on applicability of fast bitmap processing path
3610 * @value_bitmap: bitmap of values to assign
3612 * Set the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status
3615 * This function is to be called from contexts that can sleep.
3617 int gpiod_set_array_value_cansleep(unsigned int array_size,
3618 struct gpio_desc **desc_array,
3619 struct gpio_array *array_info,
3620 unsigned long *value_bitmap)
3622 might_sleep_if(extra_checks);
3625 return gpiod_set_array_value_complex(false, true, array_size,
3626 desc_array, array_info,
3629 EXPORT_SYMBOL_GPL(gpiod_set_array_value_cansleep);
3632 * gpiod_add_lookup_table() - register GPIO device consumers
3633 * @table: table of consumers to register
3635 void gpiod_add_lookup_table(struct gpiod_lookup_table *table)
3637 gpiod_add_lookup_tables(&table, 1);
3639 EXPORT_SYMBOL_GPL(gpiod_add_lookup_table);
3642 * gpiod_remove_lookup_table() - unregister GPIO device consumers
3643 * @table: table of consumers to unregister
3645 void gpiod_remove_lookup_table(struct gpiod_lookup_table *table)
3647 /* Nothing to remove */
3651 mutex_lock(&gpio_lookup_lock);
3653 list_del(&table->list);
3655 mutex_unlock(&gpio_lookup_lock);
3657 EXPORT_SYMBOL_GPL(gpiod_remove_lookup_table);
3660 * gpiod_add_hogs() - register a set of GPIO hogs from machine code
3661 * @hogs: table of gpio hog entries with a zeroed sentinel at the end
3663 void gpiod_add_hogs(struct gpiod_hog *hogs)
3665 struct gpio_chip *gc;
3666 struct gpiod_hog *hog;
3668 mutex_lock(&gpio_machine_hogs_mutex);
3670 for (hog = &hogs[0]; hog->chip_label; hog++) {
3671 list_add_tail(&hog->list, &gpio_machine_hogs);
3674 * The chip may have been registered earlier, so check if it
3675 * exists and, if so, try to hog the line now.
3677 gc = find_chip_by_name(hog->chip_label);
3679 gpiochip_machine_hog(gc, hog);
3682 mutex_unlock(&gpio_machine_hogs_mutex);
3684 EXPORT_SYMBOL_GPL(gpiod_add_hogs);
3686 void gpiod_remove_hogs(struct gpiod_hog *hogs)
3688 struct gpiod_hog *hog;
3690 mutex_lock(&gpio_machine_hogs_mutex);
3691 for (hog = &hogs[0]; hog->chip_label; hog++)
3692 list_del(&hog->list);
3693 mutex_unlock(&gpio_machine_hogs_mutex);
3695 EXPORT_SYMBOL_GPL(gpiod_remove_hogs);
3697 static struct gpiod_lookup_table *gpiod_find_lookup_table(struct device *dev)
3699 const char *dev_id = dev ? dev_name(dev) : NULL;
3700 struct gpiod_lookup_table *table;
3702 mutex_lock(&gpio_lookup_lock);
3704 list_for_each_entry(table, &gpio_lookup_list, list) {
3705 if (table->dev_id && dev_id) {
3707 * Valid strings on both ends, must be identical to have
3710 if (!strcmp(table->dev_id, dev_id))
3714 * One of the pointers is NULL, so both must be to have
3717 if (dev_id == table->dev_id)
3724 mutex_unlock(&gpio_lookup_lock);
3728 static struct gpio_desc *gpiod_find(struct device *dev, const char *con_id,
3729 unsigned int idx, unsigned long *flags)
3731 struct gpio_desc *desc = ERR_PTR(-ENOENT);
3732 struct gpiod_lookup_table *table;
3733 struct gpiod_lookup *p;
3735 table = gpiod_find_lookup_table(dev);
3739 for (p = &table->table[0]; p->key; p++) {
3740 struct gpio_chip *gc;
3742 /* idx must always match exactly */
3746 /* If the lookup entry has a con_id, require exact match */
3747 if (p->con_id && (!con_id || strcmp(p->con_id, con_id)))
3750 if (p->chip_hwnum == U16_MAX) {
3751 desc = gpio_name_to_desc(p->key);
3757 dev_warn(dev, "cannot find GPIO line %s, deferring\n",
3759 return ERR_PTR(-EPROBE_DEFER);
3762 gc = find_chip_by_name(p->key);
3766 * As the lookup table indicates a chip with
3767 * p->key should exist, assume it may
3768 * still appear later and let the interested
3769 * consumer be probed again or let the Deferred
3770 * Probe infrastructure handle the error.
3772 dev_warn(dev, "cannot find GPIO chip %s, deferring\n",
3774 return ERR_PTR(-EPROBE_DEFER);
3777 if (gc->ngpio <= p->chip_hwnum) {
3779 "requested GPIO %u (%u) is out of range [0..%u] for chip %s\n",
3780 idx, p->chip_hwnum, gc->ngpio - 1,
3782 return ERR_PTR(-EINVAL);
3785 desc = gpiochip_get_desc(gc, p->chip_hwnum);
3794 static int platform_gpio_count(struct device *dev, const char *con_id)
3796 struct gpiod_lookup_table *table;
3797 struct gpiod_lookup *p;
3798 unsigned int count = 0;
3800 table = gpiod_find_lookup_table(dev);
3804 for (p = &table->table[0]; p->key; p++) {
3805 if ((con_id && p->con_id && !strcmp(con_id, p->con_id)) ||
3806 (!con_id && !p->con_id))
3816 * fwnode_get_named_gpiod - obtain a GPIO from firmware node
3817 * @fwnode: handle of the firmware node
3818 * @propname: name of the firmware property representing the GPIO
3819 * @index: index of the GPIO to obtain for the consumer
3820 * @dflags: GPIO initialization flags
3821 * @label: label to attach to the requested GPIO
3823 * This function can be used for drivers that get their configuration
3824 * from opaque firmware.
3826 * The function properly finds the corresponding GPIO using whatever is the
3827 * underlying firmware interface and then makes sure that the GPIO
3828 * descriptor is requested before it is returned to the caller.
3831 * On successful request the GPIO pin is configured in accordance with
3834 * In case of error an ERR_PTR() is returned.
3836 static struct gpio_desc *fwnode_get_named_gpiod(struct fwnode_handle *fwnode,
3837 const char *propname, int index,
3838 enum gpiod_flags dflags,
3841 unsigned long lflags = GPIO_LOOKUP_FLAGS_DEFAULT;
3842 struct gpio_desc *desc = ERR_PTR(-ENODEV);
3845 if (is_of_node(fwnode)) {
3846 desc = gpiod_get_from_of_node(to_of_node(fwnode),
3851 } else if (is_acpi_node(fwnode)) {
3852 struct acpi_gpio_info info;
3854 desc = acpi_node_get_gpiod(fwnode, propname, index, &info);
3858 acpi_gpio_update_gpiod_flags(&dflags, &info);
3859 acpi_gpio_update_gpiod_lookup_flags(&lflags, &info);
3861 return ERR_PTR(-EINVAL);
3864 /* Currently only ACPI takes this path */
3865 ret = gpiod_request(desc, label);
3867 return ERR_PTR(ret);
3869 ret = gpiod_configure_flags(desc, propname, lflags, dflags);
3872 return ERR_PTR(ret);
3875 blocking_notifier_call_chain(&desc->gdev->notifier,
3876 GPIOLINE_CHANGED_REQUESTED, desc);
3882 * fwnode_gpiod_get_index - obtain a GPIO from firmware node
3883 * @fwnode: handle of the firmware node
3884 * @con_id: function within the GPIO consumer
3885 * @index: index of the GPIO to obtain for the consumer
3886 * @flags: GPIO initialization flags
3887 * @label: label to attach to the requested GPIO
3889 * This function can be used for drivers that get their configuration
3890 * from opaque firmware.
3892 * The function properly finds the corresponding GPIO using whatever is the
3893 * underlying firmware interface and then makes sure that the GPIO
3894 * descriptor is requested before it is returned to the caller.
3897 * On successful request the GPIO pin is configured in accordance with
3900 * In case of error an ERR_PTR() is returned.
3902 struct gpio_desc *fwnode_gpiod_get_index(struct fwnode_handle *fwnode,
3903 const char *con_id, int index,
3904 enum gpiod_flags flags,
3907 struct gpio_desc *desc;
3908 char prop_name[32]; /* 32 is max size of property name */
3911 for (i = 0; i < ARRAY_SIZE(gpio_suffixes); i++) {
3913 snprintf(prop_name, sizeof(prop_name), "%s-%s",
3914 con_id, gpio_suffixes[i]);
3916 snprintf(prop_name, sizeof(prop_name), "%s",
3919 desc = fwnode_get_named_gpiod(fwnode, prop_name, index, flags,
3921 if (!gpiod_not_found(desc))
3927 EXPORT_SYMBOL_GPL(fwnode_gpiod_get_index);
3930 * gpiod_count - return the number of GPIOs associated with a device / function
3931 * or -ENOENT if no GPIO has been assigned to the requested function
3932 * @dev: GPIO consumer, can be NULL for system-global GPIOs
3933 * @con_id: function within the GPIO consumer
3935 int gpiod_count(struct device *dev, const char *con_id)
3937 const struct fwnode_handle *fwnode = dev ? dev_fwnode(dev) : NULL;
3938 int count = -ENOENT;
3940 if (is_of_node(fwnode))
3941 count = of_gpio_get_count(dev, con_id);
3942 else if (is_acpi_node(fwnode))
3943 count = acpi_gpio_count(dev, con_id);
3946 count = platform_gpio_count(dev, con_id);
3950 EXPORT_SYMBOL_GPL(gpiod_count);
3953 * gpiod_get - obtain a GPIO for a given GPIO function
3954 * @dev: GPIO consumer, can be NULL for system-global GPIOs
3955 * @con_id: function within the GPIO consumer
3956 * @flags: optional GPIO initialization flags
3958 * Return the GPIO descriptor corresponding to the function con_id of device
3959 * dev, -ENOENT if no GPIO has been assigned to the requested function, or
3960 * another IS_ERR() code if an error occurred while trying to acquire the GPIO.
3962 struct gpio_desc *__must_check gpiod_get(struct device *dev, const char *con_id,
3963 enum gpiod_flags flags)
3965 return gpiod_get_index(dev, con_id, 0, flags);
3967 EXPORT_SYMBOL_GPL(gpiod_get);
3970 * gpiod_get_optional - obtain an optional GPIO for a given GPIO function
3971 * @dev: GPIO consumer, can be NULL for system-global GPIOs
3972 * @con_id: function within the GPIO consumer
3973 * @flags: optional GPIO initialization flags
3975 * This is equivalent to gpiod_get(), except that when no GPIO was assigned to
3976 * the requested function it will return NULL. This is convenient for drivers
3977 * that need to handle optional GPIOs.
3979 struct gpio_desc *__must_check gpiod_get_optional(struct device *dev,
3981 enum gpiod_flags flags)
3983 return gpiod_get_index_optional(dev, con_id, 0, flags);
3985 EXPORT_SYMBOL_GPL(gpiod_get_optional);
3989 * gpiod_configure_flags - helper function to configure a given GPIO
3990 * @desc: gpio whose value will be assigned
3991 * @con_id: function within the GPIO consumer
3992 * @lflags: bitmask of gpio_lookup_flags GPIO_* values - returned from
3993 * of_find_gpio() or of_get_gpio_hog()
3994 * @dflags: gpiod_flags - optional GPIO initialization flags
3996 * Return 0 on success, -ENOENT if no GPIO has been assigned to the
3997 * requested function and/or index, or another IS_ERR() code if an error
3998 * occurred while trying to acquire the GPIO.
4000 int gpiod_configure_flags(struct gpio_desc *desc, const char *con_id,
4001 unsigned long lflags, enum gpiod_flags dflags)
4005 if (lflags & GPIO_ACTIVE_LOW)
4006 set_bit(FLAG_ACTIVE_LOW, &desc->flags);
4008 if (lflags & GPIO_OPEN_DRAIN)
4009 set_bit(FLAG_OPEN_DRAIN, &desc->flags);
4010 else if (dflags & GPIOD_FLAGS_BIT_OPEN_DRAIN) {
4012 * This enforces open drain mode from the consumer side.
4013 * This is necessary for some busses like I2C, but the lookup
4014 * should *REALLY* have specified them as open drain in the
4015 * first place, so print a little warning here.
4017 set_bit(FLAG_OPEN_DRAIN, &desc->flags);
4019 "enforced open drain please flag it properly in DT/ACPI DSDT/board file\n");
4022 if (lflags & GPIO_OPEN_SOURCE)
4023 set_bit(FLAG_OPEN_SOURCE, &desc->flags);
4025 if (((lflags & GPIO_PULL_UP) && (lflags & GPIO_PULL_DOWN)) ||
4026 ((lflags & GPIO_PULL_UP) && (lflags & GPIO_PULL_DISABLE)) ||
4027 ((lflags & GPIO_PULL_DOWN) && (lflags & GPIO_PULL_DISABLE))) {
4029 "multiple pull-up, pull-down or pull-disable enabled, invalid configuration\n");
4033 if (lflags & GPIO_PULL_UP)
4034 set_bit(FLAG_PULL_UP, &desc->flags);
4035 else if (lflags & GPIO_PULL_DOWN)
4036 set_bit(FLAG_PULL_DOWN, &desc->flags);
4037 else if (lflags & GPIO_PULL_DISABLE)
4038 set_bit(FLAG_BIAS_DISABLE, &desc->flags);
4040 ret = gpiod_set_transitory(desc, (lflags & GPIO_TRANSITORY));
4044 /* No particular flag request, return here... */
4045 if (!(dflags & GPIOD_FLAGS_BIT_DIR_SET)) {
4046 gpiod_dbg(desc, "no flags found for %s\n", con_id);
4051 if (dflags & GPIOD_FLAGS_BIT_DIR_OUT)
4052 ret = gpiod_direction_output(desc,
4053 !!(dflags & GPIOD_FLAGS_BIT_DIR_VAL));
4055 ret = gpiod_direction_input(desc);
4061 * gpiod_get_index - obtain a GPIO from a multi-index GPIO function
4062 * @dev: GPIO consumer, can be NULL for system-global GPIOs
4063 * @con_id: function within the GPIO consumer
4064 * @idx: index of the GPIO to obtain in the consumer
4065 * @flags: optional GPIO initialization flags
4067 * This variant of gpiod_get() allows to access GPIOs other than the first
4068 * defined one for functions that define several GPIOs.
4070 * Return a valid GPIO descriptor, -ENOENT if no GPIO has been assigned to the
4071 * requested function and/or index, or another IS_ERR() code if an error
4072 * occurred while trying to acquire the GPIO.
4074 struct gpio_desc *__must_check gpiod_get_index(struct device *dev,
4077 enum gpiod_flags flags)
4079 unsigned long lookupflags = GPIO_LOOKUP_FLAGS_DEFAULT;
4080 struct gpio_desc *desc = NULL;
4082 /* Maybe we have a device name, maybe not */
4083 const char *devname = dev ? dev_name(dev) : "?";
4084 const struct fwnode_handle *fwnode = dev ? dev_fwnode(dev) : NULL;
4086 dev_dbg(dev, "GPIO lookup for consumer %s\n", con_id);
4088 /* Using device tree? */
4089 if (is_of_node(fwnode)) {
4090 dev_dbg(dev, "using device tree for GPIO lookup\n");
4091 desc = of_find_gpio(dev, con_id, idx, &lookupflags);
4092 } else if (is_acpi_node(fwnode)) {
4093 dev_dbg(dev, "using ACPI for GPIO lookup\n");
4094 desc = acpi_find_gpio(dev, con_id, idx, &flags, &lookupflags);
4098 * Either we are not using DT or ACPI, or their lookup did not return
4099 * a result. In that case, use platform lookup as a fallback.
4101 if (!desc || gpiod_not_found(desc)) {
4102 dev_dbg(dev, "using lookup tables for GPIO lookup\n");
4103 desc = gpiod_find(dev, con_id, idx, &lookupflags);
4107 dev_dbg(dev, "No GPIO consumer %s found\n", con_id);
4112 * If a connection label was passed use that, else attempt to use
4113 * the device name as label
4115 ret = gpiod_request(desc, con_id ?: devname);
4117 if (!(ret == -EBUSY && flags & GPIOD_FLAGS_BIT_NONEXCLUSIVE))
4118 return ERR_PTR(ret);
4121 * This happens when there are several consumers for
4122 * the same GPIO line: we just return here without
4123 * further initialization. It is a bit of a hack.
4124 * This is necessary to support fixed regulators.
4126 * FIXME: Make this more sane and safe.
4128 dev_info(dev, "nonexclusive access to GPIO for %s\n", con_id ?: devname);
4132 ret = gpiod_configure_flags(desc, con_id, lookupflags, flags);
4134 dev_dbg(dev, "setup of GPIO %s failed\n", con_id);
4136 return ERR_PTR(ret);
4139 blocking_notifier_call_chain(&desc->gdev->notifier,
4140 GPIOLINE_CHANGED_REQUESTED, desc);
4144 EXPORT_SYMBOL_GPL(gpiod_get_index);
4147 * gpiod_get_index_optional - obtain an optional GPIO from a multi-index GPIO
4149 * @dev: GPIO consumer, can be NULL for system-global GPIOs
4150 * @con_id: function within the GPIO consumer
4151 * @index: index of the GPIO to obtain in the consumer
4152 * @flags: optional GPIO initialization flags
4154 * This is equivalent to gpiod_get_index(), except that when no GPIO with the
4155 * specified index was assigned to the requested function it will return NULL.
4156 * This is convenient for drivers that need to handle optional GPIOs.
4158 struct gpio_desc *__must_check gpiod_get_index_optional(struct device *dev,
4161 enum gpiod_flags flags)
4163 struct gpio_desc *desc;
4165 desc = gpiod_get_index(dev, con_id, index, flags);
4166 if (gpiod_not_found(desc))
4171 EXPORT_SYMBOL_GPL(gpiod_get_index_optional);
4174 * gpiod_hog - Hog the specified GPIO desc given the provided flags
4175 * @desc: gpio whose value will be assigned
4176 * @name: gpio line name
4177 * @lflags: bitmask of gpio_lookup_flags GPIO_* values - returned from
4178 * of_find_gpio() or of_get_gpio_hog()
4179 * @dflags: gpiod_flags - optional GPIO initialization flags
4181 int gpiod_hog(struct gpio_desc *desc, const char *name,
4182 unsigned long lflags, enum gpiod_flags dflags)
4184 struct gpio_chip *gc;
4185 struct gpio_desc *local_desc;
4189 gc = gpiod_to_chip(desc);
4190 hwnum = gpio_chip_hwgpio(desc);
4192 local_desc = gpiochip_request_own_desc(gc, hwnum, name,
4194 if (IS_ERR(local_desc)) {
4195 ret = PTR_ERR(local_desc);
4196 pr_err("requesting hog GPIO %s (chip %s, offset %d) failed, %d\n",
4197 name, gc->label, hwnum, ret);
4201 /* Mark GPIO as hogged so it can be identified and removed later */
4202 set_bit(FLAG_IS_HOGGED, &desc->flags);
4204 gpiod_info(desc, "hogged as %s%s\n",
4205 (dflags & GPIOD_FLAGS_BIT_DIR_OUT) ? "output" : "input",
4206 (dflags & GPIOD_FLAGS_BIT_DIR_OUT) ?
4207 (dflags & GPIOD_FLAGS_BIT_DIR_VAL) ? "/high" : "/low" : "");
4213 * gpiochip_free_hogs - Scan gpio-controller chip and release GPIO hog
4214 * @gc: gpio chip to act on
4216 static void gpiochip_free_hogs(struct gpio_chip *gc)
4218 struct gpio_desc *desc;
4220 for_each_gpio_desc_with_flag(gc, desc, FLAG_IS_HOGGED)
4221 gpiochip_free_own_desc(desc);
4225 * gpiod_get_array - obtain multiple GPIOs from a multi-index GPIO function
4226 * @dev: GPIO consumer, can be NULL for system-global GPIOs
4227 * @con_id: function within the GPIO consumer
4228 * @flags: optional GPIO initialization flags
4230 * This function acquires all the GPIOs defined under a given function.
4232 * Return a struct gpio_descs containing an array of descriptors, -ENOENT if
4233 * no GPIO has been assigned to the requested function, or another IS_ERR()
4234 * code if an error occurred while trying to acquire the GPIOs.
4236 struct gpio_descs *__must_check gpiod_get_array(struct device *dev,
4238 enum gpiod_flags flags)
4240 struct gpio_desc *desc;
4241 struct gpio_descs *descs;
4242 struct gpio_array *array_info = NULL;
4243 struct gpio_chip *gc;
4244 int count, bitmap_size;
4246 count = gpiod_count(dev, con_id);
4248 return ERR_PTR(count);
4250 descs = kzalloc(struct_size(descs, desc, count), GFP_KERNEL);
4252 return ERR_PTR(-ENOMEM);
4254 for (descs->ndescs = 0; descs->ndescs < count; ) {
4255 desc = gpiod_get_index(dev, con_id, descs->ndescs, flags);
4257 gpiod_put_array(descs);
4258 return ERR_CAST(desc);
4261 descs->desc[descs->ndescs] = desc;
4263 gc = gpiod_to_chip(desc);
4265 * If pin hardware number of array member 0 is also 0, select
4266 * its chip as a candidate for fast bitmap processing path.
4268 if (descs->ndescs == 0 && gpio_chip_hwgpio(desc) == 0) {
4269 struct gpio_descs *array;
4271 bitmap_size = BITS_TO_LONGS(gc->ngpio > count ?
4274 array = kzalloc(struct_size(descs, desc, count) +
4275 struct_size(array_info, invert_mask,
4276 3 * bitmap_size), GFP_KERNEL);
4278 gpiod_put_array(descs);
4279 return ERR_PTR(-ENOMEM);
4282 memcpy(array, descs,
4283 struct_size(descs, desc, descs->ndescs + 1));
4287 array_info = (void *)(descs->desc + count);
4288 array_info->get_mask = array_info->invert_mask +
4290 array_info->set_mask = array_info->get_mask +
4293 array_info->desc = descs->desc;
4294 array_info->size = count;
4295 array_info->chip = gc;
4296 bitmap_set(array_info->get_mask, descs->ndescs,
4297 count - descs->ndescs);
4298 bitmap_set(array_info->set_mask, descs->ndescs,
4299 count - descs->ndescs);
4300 descs->info = array_info;
4302 /* Unmark array members which don't belong to the 'fast' chip */
4303 if (array_info && array_info->chip != gc) {
4304 __clear_bit(descs->ndescs, array_info->get_mask);
4305 __clear_bit(descs->ndescs, array_info->set_mask);
4308 * Detect array members which belong to the 'fast' chip
4309 * but their pins are not in hardware order.
4311 else if (array_info &&
4312 gpio_chip_hwgpio(desc) != descs->ndescs) {
4314 * Don't use fast path if all array members processed so
4315 * far belong to the same chip as this one but its pin
4316 * hardware number is different from its array index.
4318 if (bitmap_full(array_info->get_mask, descs->ndescs)) {
4321 __clear_bit(descs->ndescs,
4322 array_info->get_mask);
4323 __clear_bit(descs->ndescs,
4324 array_info->set_mask);
4326 } else if (array_info) {
4327 /* Exclude open drain or open source from fast output */
4328 if (gpiochip_line_is_open_drain(gc, descs->ndescs) ||
4329 gpiochip_line_is_open_source(gc, descs->ndescs))
4330 __clear_bit(descs->ndescs,
4331 array_info->set_mask);
4332 /* Identify 'fast' pins which require invertion */
4333 if (gpiod_is_active_low(desc))
4334 __set_bit(descs->ndescs,
4335 array_info->invert_mask);
4342 "GPIO array info: chip=%s, size=%d, get_mask=%lx, set_mask=%lx, invert_mask=%lx\n",
4343 array_info->chip->label, array_info->size,
4344 *array_info->get_mask, *array_info->set_mask,
4345 *array_info->invert_mask);
4348 EXPORT_SYMBOL_GPL(gpiod_get_array);
4351 * gpiod_get_array_optional - obtain multiple GPIOs from a multi-index GPIO
4353 * @dev: GPIO consumer, can be NULL for system-global GPIOs
4354 * @con_id: function within the GPIO consumer
4355 * @flags: optional GPIO initialization flags
4357 * This is equivalent to gpiod_get_array(), except that when no GPIO was
4358 * assigned to the requested function it will return NULL.
4360 struct gpio_descs *__must_check gpiod_get_array_optional(struct device *dev,
4362 enum gpiod_flags flags)
4364 struct gpio_descs *descs;
4366 descs = gpiod_get_array(dev, con_id, flags);
4367 if (gpiod_not_found(descs))
4372 EXPORT_SYMBOL_GPL(gpiod_get_array_optional);
4375 * gpiod_put - dispose of a GPIO descriptor
4376 * @desc: GPIO descriptor to dispose of
4378 * No descriptor can be used after gpiod_put() has been called on it.
4380 void gpiod_put(struct gpio_desc *desc)
4385 EXPORT_SYMBOL_GPL(gpiod_put);
4388 * gpiod_put_array - dispose of multiple GPIO descriptors
4389 * @descs: struct gpio_descs containing an array of descriptors
4391 void gpiod_put_array(struct gpio_descs *descs)
4395 for (i = 0; i < descs->ndescs; i++)
4396 gpiod_put(descs->desc[i]);
4400 EXPORT_SYMBOL_GPL(gpiod_put_array);
4403 static int gpio_bus_match(struct device *dev, struct device_driver *drv)
4405 struct fwnode_handle *fwnode = dev_fwnode(dev);
4408 * Only match if the fwnode doesn't already have a proper struct device
4411 if (fwnode && fwnode->dev != dev)
4416 static int gpio_stub_drv_probe(struct device *dev)
4419 * The DT node of some GPIO chips have a "compatible" property, but
4420 * never have a struct device added and probed by a driver to register
4421 * the GPIO chip with gpiolib. In such cases, fw_devlink=on will cause
4422 * the consumers of the GPIO chip to get probe deferred forever because
4423 * they will be waiting for a device associated with the GPIO chip
4424 * firmware node to get added and bound to a driver.
4426 * To allow these consumers to probe, we associate the struct
4427 * gpio_device of the GPIO chip with the firmware node and then simply
4428 * bind it to this stub driver.
4433 static struct device_driver gpio_stub_drv = {
4434 .name = "gpio_stub_drv",
4435 .bus = &gpio_bus_type,
4436 .probe = gpio_stub_drv_probe,
4439 static int __init gpiolib_dev_init(void)
4443 /* Register GPIO sysfs bus */
4444 ret = bus_register(&gpio_bus_type);
4446 pr_err("gpiolib: could not register GPIO bus type\n");
4450 ret = driver_register(&gpio_stub_drv);
4452 pr_err("gpiolib: could not register GPIO stub driver\n");
4453 bus_unregister(&gpio_bus_type);
4457 ret = alloc_chrdev_region(&gpio_devt, 0, GPIO_DEV_MAX, GPIOCHIP_NAME);
4459 pr_err("gpiolib: failed to allocate char dev region\n");
4460 driver_unregister(&gpio_stub_drv);
4461 bus_unregister(&gpio_bus_type);
4465 gpiolib_initialized = true;
4466 gpiochip_setup_devs();
4468 #if IS_ENABLED(CONFIG_OF_DYNAMIC) && IS_ENABLED(CONFIG_OF_GPIO)
4469 WARN_ON(of_reconfig_notifier_register(&gpio_of_notifier));
4470 #endif /* CONFIG_OF_DYNAMIC && CONFIG_OF_GPIO */
4474 core_initcall(gpiolib_dev_init);
4476 #ifdef CONFIG_DEBUG_FS
4478 static void gpiolib_dbg_show(struct seq_file *s, struct gpio_device *gdev)
4480 struct gpio_chip *gc = gdev->chip;
4481 struct gpio_desc *desc;
4482 unsigned gpio = gdev->base;
4488 for_each_gpio_desc(gc, desc) {
4489 if (test_bit(FLAG_REQUESTED, &desc->flags)) {
4490 gpiod_get_direction(desc);
4491 is_out = test_bit(FLAG_IS_OUT, &desc->flags);
4492 value = gpio_chip_get_value(gc, desc);
4493 is_irq = test_bit(FLAG_USED_AS_IRQ, &desc->flags);
4494 active_low = test_bit(FLAG_ACTIVE_LOW, &desc->flags);
4495 seq_printf(s, " gpio-%-3d (%-20.20s|%-20.20s) %s %s %s%s\n",
4496 gpio, desc->name ?: "", desc->label,
4497 is_out ? "out" : "in ",
4498 value >= 0 ? (value ? "hi" : "lo") : "? ",
4499 is_irq ? "IRQ " : "",
4500 active_low ? "ACTIVE LOW" : "");
4501 } else if (desc->name) {
4502 seq_printf(s, " gpio-%-3d (%-20.20s)\n", gpio, desc->name);
4509 static void *gpiolib_seq_start(struct seq_file *s, loff_t *pos)
4511 unsigned long flags;
4512 struct gpio_device *gdev = NULL;
4513 loff_t index = *pos;
4517 spin_lock_irqsave(&gpio_lock, flags);
4518 list_for_each_entry(gdev, &gpio_devices, list)
4520 spin_unlock_irqrestore(&gpio_lock, flags);
4523 spin_unlock_irqrestore(&gpio_lock, flags);
4528 static void *gpiolib_seq_next(struct seq_file *s, void *v, loff_t *pos)
4530 unsigned long flags;
4531 struct gpio_device *gdev = v;
4534 spin_lock_irqsave(&gpio_lock, flags);
4535 if (list_is_last(&gdev->list, &gpio_devices))
4538 ret = list_first_entry(&gdev->list, struct gpio_device, list);
4539 spin_unlock_irqrestore(&gpio_lock, flags);
4547 static void gpiolib_seq_stop(struct seq_file *s, void *v)
4551 static int gpiolib_seq_show(struct seq_file *s, void *v)
4553 struct gpio_device *gdev = v;
4554 struct gpio_chip *gc = gdev->chip;
4555 struct device *parent;
4558 seq_printf(s, "%s%s: (dangling chip)", (char *)s->private,
4559 dev_name(&gdev->dev));
4563 seq_printf(s, "%s%s: GPIOs %d-%d", (char *)s->private,
4564 dev_name(&gdev->dev),
4565 gdev->base, gdev->base + gdev->ngpio - 1);
4566 parent = gc->parent;
4568 seq_printf(s, ", parent: %s/%s",
4569 parent->bus ? parent->bus->name : "no-bus",
4572 seq_printf(s, ", %s", gc->label);
4574 seq_printf(s, ", can sleep");
4575 seq_printf(s, ":\n");
4578 gc->dbg_show(s, gc);
4580 gpiolib_dbg_show(s, gdev);
4585 static const struct seq_operations gpiolib_sops = {
4586 .start = gpiolib_seq_start,
4587 .next = gpiolib_seq_next,
4588 .stop = gpiolib_seq_stop,
4589 .show = gpiolib_seq_show,
4591 DEFINE_SEQ_ATTRIBUTE(gpiolib);
4593 static int __init gpiolib_debugfs_init(void)
4595 /* /sys/kernel/debug/gpio */
4596 debugfs_create_file("gpio", 0444, NULL, NULL, &gpiolib_fops);
4599 subsys_initcall(gpiolib_debugfs_init);
4601 #endif /* DEBUG_FS */