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);
739 #ifdef CONFIG_PINCTRL
740 INIT_LIST_HEAD(&gdev->pin_ranges);
744 ret = gpiochip_set_desc_names(gc);
746 goto err_remove_from_list;
748 ret = devprop_gpiochip_set_names(gc);
750 goto err_remove_from_list;
752 ret = gpiochip_alloc_valid_mask(gc);
754 goto err_remove_from_list;
756 ret = of_gpiochip_add(gc);
758 goto err_free_gpiochip_mask;
760 ret = gpiochip_init_valid_mask(gc);
762 goto err_remove_of_chip;
764 for (i = 0; i < gc->ngpio; i++) {
765 struct gpio_desc *desc = &gdev->descs[i];
767 if (gc->get_direction && gpiochip_line_is_valid(gc, i)) {
768 assign_bit(FLAG_IS_OUT,
769 &desc->flags, !gc->get_direction(gc, i));
771 assign_bit(FLAG_IS_OUT,
772 &desc->flags, !gc->direction_input);
776 ret = gpiochip_add_pin_ranges(gc);
778 goto err_remove_of_chip;
780 acpi_gpiochip_add(gc);
782 machine_gpiochip_add(gc);
784 ret = gpiochip_irqchip_init_valid_mask(gc);
786 goto err_remove_acpi_chip;
788 ret = gpiochip_irqchip_init_hw(gc);
790 goto err_remove_acpi_chip;
792 ret = gpiochip_add_irqchip(gc, lock_key, request_key);
794 goto err_remove_irqchip_mask;
797 * By first adding the chardev, and then adding the device,
798 * we get a device node entry in sysfs under
799 * /sys/bus/gpio/devices/gpiochipN/dev that can be used for
800 * coldplug of device nodes and other udev business.
801 * We can do this only if gpiolib has been initialized.
802 * Otherwise, defer until later.
804 if (gpiolib_initialized) {
805 ret = gpiochip_setup_dev(gdev);
807 goto err_remove_irqchip;
812 gpiochip_irqchip_remove(gc);
813 err_remove_irqchip_mask:
814 gpiochip_irqchip_free_valid_mask(gc);
815 err_remove_acpi_chip:
816 acpi_gpiochip_remove(gc);
818 gpiochip_free_hogs(gc);
819 of_gpiochip_remove(gc);
820 err_free_gpiochip_mask:
821 gpiochip_remove_pin_ranges(gc);
822 gpiochip_free_valid_mask(gc);
823 if (gdev->dev.release) {
824 /* release() has been registered by gpiochip_setup_dev() */
825 put_device(&gdev->dev);
826 goto err_print_message;
828 err_remove_from_list:
829 spin_lock_irqsave(&gpio_lock, flags);
830 list_del(&gdev->list);
831 spin_unlock_irqrestore(&gpio_lock, flags);
833 kfree_const(gdev->label);
837 kfree(dev_name(&gdev->dev));
839 ida_free(&gpio_ida, gdev->id);
843 /* failures here can mean systems won't boot... */
844 if (ret != -EPROBE_DEFER) {
845 pr_err("%s: GPIOs %d..%d (%s) failed to register, %d\n", __func__,
846 base, base + (int)ngpios - 1,
847 gc->label ? : "generic", ret);
851 EXPORT_SYMBOL_GPL(gpiochip_add_data_with_key);
854 * gpiochip_get_data() - get per-subdriver data for the chip
858 * The per-subdriver data for the chip.
860 void *gpiochip_get_data(struct gpio_chip *gc)
862 return gc->gpiodev->data;
864 EXPORT_SYMBOL_GPL(gpiochip_get_data);
867 * gpiochip_remove() - unregister a gpio_chip
868 * @gc: the chip to unregister
870 * A gpio_chip with any GPIOs still requested may not be removed.
872 void gpiochip_remove(struct gpio_chip *gc)
874 struct gpio_device *gdev = gc->gpiodev;
878 /* FIXME: should the legacy sysfs handling be moved to gpio_device? */
879 gpiochip_sysfs_unregister(gdev);
880 gpiochip_free_hogs(gc);
881 /* Numb the device, cancelling all outstanding operations */
883 gpiochip_irqchip_remove(gc);
884 acpi_gpiochip_remove(gc);
885 of_gpiochip_remove(gc);
886 gpiochip_remove_pin_ranges(gc);
887 gpiochip_free_valid_mask(gc);
889 * We accept no more calls into the driver from this point, so
890 * NULL the driver data pointer
894 spin_lock_irqsave(&gpio_lock, flags);
895 for (i = 0; i < gdev->ngpio; i++) {
896 if (gpiochip_is_requested(gc, i))
899 spin_unlock_irqrestore(&gpio_lock, flags);
901 if (i != gdev->ngpio)
903 "REMOVING GPIOCHIP WITH GPIOS STILL REQUESTED\n");
906 * The gpiochip side puts its use of the device to rest here:
907 * if there are no userspace clients, the chardev and device will
908 * be removed, else it will be dangling until the last user is
911 gcdev_unregister(gdev);
912 put_device(&gdev->dev);
914 EXPORT_SYMBOL_GPL(gpiochip_remove);
917 * gpiochip_find() - iterator for locating a specific gpio_chip
918 * @data: data to pass to match function
919 * @match: Callback function to check gpio_chip
921 * Similar to bus_find_device. It returns a reference to a gpio_chip as
922 * determined by a user supplied @match callback. The callback should return
923 * 0 if the device doesn't match and non-zero if it does. If the callback is
924 * non-zero, this function will return to the caller and not iterate over any
927 struct gpio_chip *gpiochip_find(void *data,
928 int (*match)(struct gpio_chip *gc,
931 struct gpio_device *gdev;
932 struct gpio_chip *gc = NULL;
935 spin_lock_irqsave(&gpio_lock, flags);
936 list_for_each_entry(gdev, &gpio_devices, list)
937 if (gdev->chip && match(gdev->chip, data)) {
942 spin_unlock_irqrestore(&gpio_lock, flags);
946 EXPORT_SYMBOL_GPL(gpiochip_find);
948 static int gpiochip_match_name(struct gpio_chip *gc, void *data)
950 const char *name = data;
952 return !strcmp(gc->label, name);
955 static struct gpio_chip *find_chip_by_name(const char *name)
957 return gpiochip_find((void *)name, gpiochip_match_name);
960 #ifdef CONFIG_GPIOLIB_IRQCHIP
963 * The following is irqchip helper code for gpiochips.
966 static int gpiochip_irqchip_init_hw(struct gpio_chip *gc)
968 struct gpio_irq_chip *girq = &gc->irq;
973 return girq->init_hw(gc);
976 static int gpiochip_irqchip_init_valid_mask(struct gpio_chip *gc)
978 struct gpio_irq_chip *girq = &gc->irq;
980 if (!girq->init_valid_mask)
983 girq->valid_mask = gpiochip_allocate_mask(gc);
984 if (!girq->valid_mask)
987 girq->init_valid_mask(gc, girq->valid_mask, gc->ngpio);
992 static void gpiochip_irqchip_free_valid_mask(struct gpio_chip *gc)
994 bitmap_free(gc->irq.valid_mask);
995 gc->irq.valid_mask = NULL;
998 bool gpiochip_irqchip_irq_valid(const struct gpio_chip *gc,
1001 if (!gpiochip_line_is_valid(gc, offset))
1003 /* No mask means all valid */
1004 if (likely(!gc->irq.valid_mask))
1006 return test_bit(offset, gc->irq.valid_mask);
1008 EXPORT_SYMBOL_GPL(gpiochip_irqchip_irq_valid);
1010 #ifdef CONFIG_IRQ_DOMAIN_HIERARCHY
1013 * gpiochip_set_hierarchical_irqchip() - connects a hierarchical irqchip
1015 * @gc: the gpiochip to set the irqchip hierarchical handler to
1016 * @irqchip: the irqchip to handle this level of the hierarchy, the interrupt
1017 * will then percolate up to the parent
1019 static void gpiochip_set_hierarchical_irqchip(struct gpio_chip *gc,
1020 struct irq_chip *irqchip)
1022 /* DT will deal with mapping each IRQ as we go along */
1023 if (is_of_node(gc->irq.fwnode))
1027 * This is for legacy and boardfile "irqchip" fwnodes: allocate
1028 * irqs upfront instead of dynamically since we don't have the
1029 * dynamic type of allocation that hardware description languages
1030 * provide. Once all GPIO drivers using board files are gone from
1031 * the kernel we can delete this code, but for a transitional period
1032 * it is necessary to keep this around.
1034 if (is_fwnode_irqchip(gc->irq.fwnode)) {
1038 for (i = 0; i < gc->ngpio; i++) {
1039 struct irq_fwspec fwspec;
1040 unsigned int parent_hwirq;
1041 unsigned int parent_type;
1042 struct gpio_irq_chip *girq = &gc->irq;
1045 * We call the child to parent translation function
1046 * only to check if the child IRQ is valid or not.
1047 * Just pick the rising edge type here as that is what
1048 * we likely need to support.
1050 ret = girq->child_to_parent_hwirq(gc, i,
1051 IRQ_TYPE_EDGE_RISING,
1055 chip_err(gc, "skip set-up on hwirq %d\n",
1060 fwspec.fwnode = gc->irq.fwnode;
1061 /* This is the hwirq for the GPIO line side of things */
1062 fwspec.param[0] = girq->child_offset_to_irq(gc, i);
1063 /* Just pick something */
1064 fwspec.param[1] = IRQ_TYPE_EDGE_RISING;
1065 fwspec.param_count = 2;
1066 ret = __irq_domain_alloc_irqs(gc->irq.domain,
1067 /* just pick something */
1076 "can not allocate irq for GPIO line %d parent hwirq %d in hierarchy domain: %d\n",
1083 chip_err(gc, "%s unknown fwnode type proceed anyway\n", __func__);
1088 static int gpiochip_hierarchy_irq_domain_translate(struct irq_domain *d,
1089 struct irq_fwspec *fwspec,
1090 unsigned long *hwirq,
1093 /* We support standard DT translation */
1094 if (is_of_node(fwspec->fwnode) && fwspec->param_count == 2) {
1095 return irq_domain_translate_twocell(d, fwspec, hwirq, type);
1098 /* This is for board files and others not using DT */
1099 if (is_fwnode_irqchip(fwspec->fwnode)) {
1102 ret = irq_domain_translate_twocell(d, fwspec, hwirq, type);
1105 WARN_ON(*type == IRQ_TYPE_NONE);
1111 static int gpiochip_hierarchy_irq_domain_alloc(struct irq_domain *d,
1113 unsigned int nr_irqs,
1116 struct gpio_chip *gc = d->host_data;
1117 irq_hw_number_t hwirq;
1118 unsigned int type = IRQ_TYPE_NONE;
1119 struct irq_fwspec *fwspec = data;
1120 union gpio_irq_fwspec gpio_parent_fwspec = {};
1121 unsigned int parent_hwirq;
1122 unsigned int parent_type;
1123 struct gpio_irq_chip *girq = &gc->irq;
1127 * The nr_irqs parameter is always one except for PCI multi-MSI
1128 * so this should not happen.
1130 WARN_ON(nr_irqs != 1);
1132 ret = gc->irq.child_irq_domain_ops.translate(d, fwspec, &hwirq, &type);
1136 chip_dbg(gc, "allocate IRQ %d, hwirq %lu\n", irq, hwirq);
1138 ret = girq->child_to_parent_hwirq(gc, hwirq, type,
1139 &parent_hwirq, &parent_type);
1141 chip_err(gc, "can't look up hwirq %lu\n", hwirq);
1144 chip_dbg(gc, "found parent hwirq %u\n", parent_hwirq);
1147 * We set handle_bad_irq because the .set_type() should
1148 * always be invoked and set the right type of handler.
1150 irq_domain_set_info(d,
1159 /* This parent only handles asserted level IRQs */
1160 ret = girq->populate_parent_alloc_arg(gc, &gpio_parent_fwspec,
1161 parent_hwirq, parent_type);
1165 chip_dbg(gc, "alloc_irqs_parent for %d parent hwirq %d\n",
1167 irq_set_lockdep_class(irq, gc->irq.lock_key, gc->irq.request_key);
1168 ret = irq_domain_alloc_irqs_parent(d, irq, 1, &gpio_parent_fwspec);
1170 * If the parent irqdomain is msi, the interrupts have already
1171 * been allocated, so the EEXIST is good.
1173 if (irq_domain_is_msi(d->parent) && (ret == -EEXIST))
1177 "failed to allocate parent hwirq %d for hwirq %lu\n",
1178 parent_hwirq, hwirq);
1183 static unsigned int gpiochip_child_offset_to_irq_noop(struct gpio_chip *gc,
1184 unsigned int offset)
1189 static void gpiochip_hierarchy_setup_domain_ops(struct irq_domain_ops *ops)
1191 ops->activate = gpiochip_irq_domain_activate;
1192 ops->deactivate = gpiochip_irq_domain_deactivate;
1193 ops->alloc = gpiochip_hierarchy_irq_domain_alloc;
1196 * We only allow overriding the translate() and free() functions for
1197 * hierarchical chips, and this should only be done if the user
1198 * really need something other than 1:1 translation for translate()
1199 * callback and free if user wants to free up any resources which
1200 * were allocated during callbacks, for example populate_parent_alloc_arg.
1202 if (!ops->translate)
1203 ops->translate = gpiochip_hierarchy_irq_domain_translate;
1205 ops->free = irq_domain_free_irqs_common;
1208 static int gpiochip_hierarchy_add_domain(struct gpio_chip *gc)
1210 if (!gc->irq.child_to_parent_hwirq ||
1212 chip_err(gc, "missing irqdomain vital data\n");
1216 if (!gc->irq.child_offset_to_irq)
1217 gc->irq.child_offset_to_irq = gpiochip_child_offset_to_irq_noop;
1219 if (!gc->irq.populate_parent_alloc_arg)
1220 gc->irq.populate_parent_alloc_arg =
1221 gpiochip_populate_parent_fwspec_twocell;
1223 gpiochip_hierarchy_setup_domain_ops(&gc->irq.child_irq_domain_ops);
1225 gc->irq.domain = irq_domain_create_hierarchy(
1226 gc->irq.parent_domain,
1230 &gc->irq.child_irq_domain_ops,
1233 if (!gc->irq.domain)
1236 gpiochip_set_hierarchical_irqchip(gc, gc->irq.chip);
1241 static bool gpiochip_hierarchy_is_hierarchical(struct gpio_chip *gc)
1243 return !!gc->irq.parent_domain;
1246 int gpiochip_populate_parent_fwspec_twocell(struct gpio_chip *gc,
1247 union gpio_irq_fwspec *gfwspec,
1248 unsigned int parent_hwirq,
1249 unsigned int parent_type)
1251 struct irq_fwspec *fwspec = &gfwspec->fwspec;
1253 fwspec->fwnode = gc->irq.parent_domain->fwnode;
1254 fwspec->param_count = 2;
1255 fwspec->param[0] = parent_hwirq;
1256 fwspec->param[1] = parent_type;
1260 EXPORT_SYMBOL_GPL(gpiochip_populate_parent_fwspec_twocell);
1262 int gpiochip_populate_parent_fwspec_fourcell(struct gpio_chip *gc,
1263 union gpio_irq_fwspec *gfwspec,
1264 unsigned int parent_hwirq,
1265 unsigned int parent_type)
1267 struct irq_fwspec *fwspec = &gfwspec->fwspec;
1269 fwspec->fwnode = gc->irq.parent_domain->fwnode;
1270 fwspec->param_count = 4;
1271 fwspec->param[0] = 0;
1272 fwspec->param[1] = parent_hwirq;
1273 fwspec->param[2] = 0;
1274 fwspec->param[3] = parent_type;
1278 EXPORT_SYMBOL_GPL(gpiochip_populate_parent_fwspec_fourcell);
1282 static int gpiochip_hierarchy_add_domain(struct gpio_chip *gc)
1287 static bool gpiochip_hierarchy_is_hierarchical(struct gpio_chip *gc)
1292 #endif /* CONFIG_IRQ_DOMAIN_HIERARCHY */
1295 * gpiochip_irq_map() - maps an IRQ into a GPIO irqchip
1296 * @d: the irqdomain used by this irqchip
1297 * @irq: the global irq number used by this GPIO irqchip irq
1298 * @hwirq: the local IRQ/GPIO line offset on this gpiochip
1300 * This function will set up the mapping for a certain IRQ line on a
1301 * gpiochip by assigning the gpiochip as chip data, and using the irqchip
1302 * stored inside the gpiochip.
1304 int gpiochip_irq_map(struct irq_domain *d, unsigned int irq,
1305 irq_hw_number_t hwirq)
1307 struct gpio_chip *gc = d->host_data;
1310 if (!gpiochip_irqchip_irq_valid(gc, hwirq))
1313 irq_set_chip_data(irq, gc);
1315 * This lock class tells lockdep that GPIO irqs are in a different
1316 * category than their parents, so it won't report false recursion.
1318 irq_set_lockdep_class(irq, gc->irq.lock_key, gc->irq.request_key);
1319 irq_set_chip_and_handler(irq, gc->irq.chip, gc->irq.handler);
1320 /* Chips that use nested thread handlers have them marked */
1321 if (gc->irq.threaded)
1322 irq_set_nested_thread(irq, 1);
1323 irq_set_noprobe(irq);
1325 if (gc->irq.num_parents == 1)
1326 ret = irq_set_parent(irq, gc->irq.parents[0]);
1327 else if (gc->irq.map)
1328 ret = irq_set_parent(irq, gc->irq.map[hwirq]);
1334 * No set-up of the hardware will happen if IRQ_TYPE_NONE
1335 * is passed as default type.
1337 if (gc->irq.default_type != IRQ_TYPE_NONE)
1338 irq_set_irq_type(irq, gc->irq.default_type);
1342 EXPORT_SYMBOL_GPL(gpiochip_irq_map);
1344 void gpiochip_irq_unmap(struct irq_domain *d, unsigned int irq)
1346 struct gpio_chip *gc = d->host_data;
1348 if (gc->irq.threaded)
1349 irq_set_nested_thread(irq, 0);
1350 irq_set_chip_and_handler(irq, NULL, NULL);
1351 irq_set_chip_data(irq, NULL);
1353 EXPORT_SYMBOL_GPL(gpiochip_irq_unmap);
1355 static const struct irq_domain_ops gpiochip_domain_ops = {
1356 .map = gpiochip_irq_map,
1357 .unmap = gpiochip_irq_unmap,
1358 /* Virtually all GPIO irqchips are twocell:ed */
1359 .xlate = irq_domain_xlate_twocell,
1363 * TODO: move these activate/deactivate in under the hierarchicial
1364 * irqchip implementation as static once SPMI and SSBI (all external
1365 * users) are phased over.
1368 * gpiochip_irq_domain_activate() - Lock a GPIO to be used as an IRQ
1369 * @domain: The IRQ domain used by this IRQ chip
1370 * @data: Outermost irq_data associated with the IRQ
1371 * @reserve: If set, only reserve an interrupt vector instead of assigning one
1373 * This function is a wrapper that calls gpiochip_lock_as_irq() and is to be
1374 * used as the activate function for the &struct irq_domain_ops. The host_data
1375 * for the IRQ domain must be the &struct gpio_chip.
1377 int gpiochip_irq_domain_activate(struct irq_domain *domain,
1378 struct irq_data *data, bool reserve)
1380 struct gpio_chip *gc = domain->host_data;
1382 return gpiochip_lock_as_irq(gc, data->hwirq);
1384 EXPORT_SYMBOL_GPL(gpiochip_irq_domain_activate);
1387 * gpiochip_irq_domain_deactivate() - Unlock a GPIO used as an IRQ
1388 * @domain: The IRQ domain used by this IRQ chip
1389 * @data: Outermost irq_data associated with the IRQ
1391 * This function is a wrapper that will call gpiochip_unlock_as_irq() and is to
1392 * be used as the deactivate function for the &struct irq_domain_ops. The
1393 * host_data for the IRQ domain must be the &struct gpio_chip.
1395 void gpiochip_irq_domain_deactivate(struct irq_domain *domain,
1396 struct irq_data *data)
1398 struct gpio_chip *gc = domain->host_data;
1400 return gpiochip_unlock_as_irq(gc, data->hwirq);
1402 EXPORT_SYMBOL_GPL(gpiochip_irq_domain_deactivate);
1404 static int gpiochip_to_irq(struct gpio_chip *gc, unsigned int offset)
1406 struct irq_domain *domain = gc->irq.domain;
1408 #ifdef CONFIG_GPIOLIB_IRQCHIP
1410 * Avoid race condition with other code, which tries to lookup
1411 * an IRQ before the irqchip has been properly registered,
1412 * i.e. while gpiochip is still being brought up.
1414 if (!gc->irq.initialized)
1415 return -EPROBE_DEFER;
1418 if (!gpiochip_irqchip_irq_valid(gc, offset))
1421 #ifdef CONFIG_IRQ_DOMAIN_HIERARCHY
1422 if (irq_domain_is_hierarchy(domain)) {
1423 struct irq_fwspec spec;
1425 spec.fwnode = domain->fwnode;
1426 spec.param_count = 2;
1427 spec.param[0] = gc->irq.child_offset_to_irq(gc, offset);
1428 spec.param[1] = IRQ_TYPE_NONE;
1430 return irq_create_fwspec_mapping(&spec);
1434 return irq_create_mapping(domain, offset);
1437 int gpiochip_irq_reqres(struct irq_data *d)
1439 struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
1441 return gpiochip_reqres_irq(gc, d->hwirq);
1443 EXPORT_SYMBOL(gpiochip_irq_reqres);
1445 void gpiochip_irq_relres(struct irq_data *d)
1447 struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
1449 gpiochip_relres_irq(gc, d->hwirq);
1451 EXPORT_SYMBOL(gpiochip_irq_relres);
1453 static void gpiochip_irq_mask(struct irq_data *d)
1455 struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
1457 if (gc->irq.irq_mask)
1458 gc->irq.irq_mask(d);
1459 gpiochip_disable_irq(gc, d->hwirq);
1462 static void gpiochip_irq_unmask(struct irq_data *d)
1464 struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
1466 gpiochip_enable_irq(gc, d->hwirq);
1467 if (gc->irq.irq_unmask)
1468 gc->irq.irq_unmask(d);
1471 static void gpiochip_irq_enable(struct irq_data *d)
1473 struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
1475 gpiochip_enable_irq(gc, d->hwirq);
1476 gc->irq.irq_enable(d);
1479 static void gpiochip_irq_disable(struct irq_data *d)
1481 struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
1483 gc->irq.irq_disable(d);
1484 gpiochip_disable_irq(gc, d->hwirq);
1487 static void gpiochip_set_irq_hooks(struct gpio_chip *gc)
1489 struct irq_chip *irqchip = gc->irq.chip;
1491 if (irqchip->flags & IRQCHIP_IMMUTABLE)
1494 chip_warn(gc, "not an immutable chip, please consider fixing it!\n");
1496 if (!irqchip->irq_request_resources &&
1497 !irqchip->irq_release_resources) {
1498 irqchip->irq_request_resources = gpiochip_irq_reqres;
1499 irqchip->irq_release_resources = gpiochip_irq_relres;
1501 if (WARN_ON(gc->irq.irq_enable))
1503 /* Check if the irqchip already has this hook... */
1504 if (irqchip->irq_enable == gpiochip_irq_enable ||
1505 irqchip->irq_mask == gpiochip_irq_mask) {
1507 * ...and if so, give a gentle warning that this is bad
1511 "detected irqchip that is shared with multiple gpiochips: please fix the driver.\n");
1515 if (irqchip->irq_disable) {
1516 gc->irq.irq_disable = irqchip->irq_disable;
1517 irqchip->irq_disable = gpiochip_irq_disable;
1519 gc->irq.irq_mask = irqchip->irq_mask;
1520 irqchip->irq_mask = gpiochip_irq_mask;
1523 if (irqchip->irq_enable) {
1524 gc->irq.irq_enable = irqchip->irq_enable;
1525 irqchip->irq_enable = gpiochip_irq_enable;
1527 gc->irq.irq_unmask = irqchip->irq_unmask;
1528 irqchip->irq_unmask = gpiochip_irq_unmask;
1533 * gpiochip_add_irqchip() - adds an IRQ chip to a GPIO chip
1534 * @gc: the GPIO chip to add the IRQ chip to
1535 * @lock_key: lockdep class for IRQ lock
1536 * @request_key: lockdep class for IRQ request
1538 static int gpiochip_add_irqchip(struct gpio_chip *gc,
1539 struct lock_class_key *lock_key,
1540 struct lock_class_key *request_key)
1542 struct fwnode_handle *fwnode = dev_fwnode(&gc->gpiodev->dev);
1543 struct irq_chip *irqchip = gc->irq.chip;
1550 if (gc->irq.parent_handler && gc->can_sleep) {
1551 chip_err(gc, "you cannot have chained interrupts on a chip that may sleep\n");
1555 type = gc->irq.default_type;
1558 * Specifying a default trigger is a terrible idea if DT or ACPI is
1559 * used to configure the interrupts, as you may end up with
1560 * conflicting triggers. Tell the user, and reset to NONE.
1562 if (WARN(fwnode && type != IRQ_TYPE_NONE,
1563 "%pfw: Ignoring %u default trigger\n", fwnode, type))
1564 type = IRQ_TYPE_NONE;
1567 chip_warn(gc, "to_irq is redefined in %s and you shouldn't rely on it\n", __func__);
1569 gc->to_irq = gpiochip_to_irq;
1570 gc->irq.default_type = type;
1571 gc->irq.lock_key = lock_key;
1572 gc->irq.request_key = request_key;
1574 /* If a parent irqdomain is provided, let's build a hierarchy */
1575 if (gpiochip_hierarchy_is_hierarchical(gc)) {
1576 int ret = gpiochip_hierarchy_add_domain(gc);
1580 /* Some drivers provide custom irqdomain ops */
1581 gc->irq.domain = irq_domain_create_simple(fwnode,
1584 gc->irq.domain_ops ?: &gpiochip_domain_ops,
1586 if (!gc->irq.domain)
1590 if (gc->irq.parent_handler) {
1591 for (i = 0; i < gc->irq.num_parents; i++) {
1594 if (gc->irq.per_parent_data)
1595 data = gc->irq.parent_handler_data_array[i];
1597 data = gc->irq.parent_handler_data ?: gc;
1600 * The parent IRQ chip is already using the chip_data
1601 * for this IRQ chip, so our callbacks simply use the
1604 irq_set_chained_handler_and_data(gc->irq.parents[i],
1605 gc->irq.parent_handler,
1610 gpiochip_set_irq_hooks(gc);
1613 * Using barrier() here to prevent compiler from reordering
1614 * gc->irq.initialized before initialization of above
1615 * GPIO chip irq members.
1619 gc->irq.initialized = true;
1621 acpi_gpiochip_request_interrupts(gc);
1627 * gpiochip_irqchip_remove() - removes an irqchip added to a gpiochip
1628 * @gc: the gpiochip to remove the irqchip from
1630 * This is called only from gpiochip_remove()
1632 static void gpiochip_irqchip_remove(struct gpio_chip *gc)
1634 struct irq_chip *irqchip = gc->irq.chip;
1635 unsigned int offset;
1637 acpi_gpiochip_free_interrupts(gc);
1639 if (irqchip && gc->irq.parent_handler) {
1640 struct gpio_irq_chip *irq = &gc->irq;
1643 for (i = 0; i < irq->num_parents; i++)
1644 irq_set_chained_handler_and_data(irq->parents[i],
1648 /* Remove all IRQ mappings and delete the domain */
1649 if (gc->irq.domain) {
1652 for (offset = 0; offset < gc->ngpio; offset++) {
1653 if (!gpiochip_irqchip_irq_valid(gc, offset))
1656 irq = irq_find_mapping(gc->irq.domain, offset);
1657 irq_dispose_mapping(irq);
1660 irq_domain_remove(gc->irq.domain);
1663 if (irqchip && !(irqchip->flags & IRQCHIP_IMMUTABLE)) {
1664 if (irqchip->irq_request_resources == gpiochip_irq_reqres) {
1665 irqchip->irq_request_resources = NULL;
1666 irqchip->irq_release_resources = NULL;
1668 if (irqchip->irq_enable == gpiochip_irq_enable) {
1669 irqchip->irq_enable = gc->irq.irq_enable;
1670 irqchip->irq_disable = gc->irq.irq_disable;
1673 gc->irq.irq_enable = NULL;
1674 gc->irq.irq_disable = NULL;
1675 gc->irq.chip = NULL;
1677 gpiochip_irqchip_free_valid_mask(gc);
1681 * gpiochip_irqchip_add_domain() - adds an irqdomain to a gpiochip
1682 * @gc: the gpiochip to add the irqchip to
1683 * @domain: the irqdomain to add to the gpiochip
1685 * This function adds an IRQ domain to the gpiochip.
1687 int gpiochip_irqchip_add_domain(struct gpio_chip *gc,
1688 struct irq_domain *domain)
1693 gc->to_irq = gpiochip_to_irq;
1694 gc->irq.domain = domain;
1698 EXPORT_SYMBOL_GPL(gpiochip_irqchip_add_domain);
1700 #else /* CONFIG_GPIOLIB_IRQCHIP */
1702 static inline int gpiochip_add_irqchip(struct gpio_chip *gc,
1703 struct lock_class_key *lock_key,
1704 struct lock_class_key *request_key)
1708 static void gpiochip_irqchip_remove(struct gpio_chip *gc) {}
1710 static inline int gpiochip_irqchip_init_hw(struct gpio_chip *gc)
1715 static inline int gpiochip_irqchip_init_valid_mask(struct gpio_chip *gc)
1719 static inline void gpiochip_irqchip_free_valid_mask(struct gpio_chip *gc)
1722 #endif /* CONFIG_GPIOLIB_IRQCHIP */
1725 * gpiochip_generic_request() - request the gpio function for a pin
1726 * @gc: the gpiochip owning the GPIO
1727 * @offset: the offset of the GPIO to request for GPIO function
1729 int gpiochip_generic_request(struct gpio_chip *gc, unsigned int offset)
1731 #ifdef CONFIG_PINCTRL
1732 if (list_empty(&gc->gpiodev->pin_ranges))
1736 return pinctrl_gpio_request(gc->gpiodev->base + offset);
1738 EXPORT_SYMBOL_GPL(gpiochip_generic_request);
1741 * gpiochip_generic_free() - free the gpio function from a pin
1742 * @gc: the gpiochip to request the gpio function for
1743 * @offset: the offset of the GPIO to free from GPIO function
1745 void gpiochip_generic_free(struct gpio_chip *gc, unsigned int offset)
1747 #ifdef CONFIG_PINCTRL
1748 if (list_empty(&gc->gpiodev->pin_ranges))
1752 pinctrl_gpio_free(gc->gpiodev->base + offset);
1754 EXPORT_SYMBOL_GPL(gpiochip_generic_free);
1757 * gpiochip_generic_config() - apply configuration for a pin
1758 * @gc: the gpiochip owning the GPIO
1759 * @offset: the offset of the GPIO to apply the configuration
1760 * @config: the configuration to be applied
1762 int gpiochip_generic_config(struct gpio_chip *gc, unsigned int offset,
1763 unsigned long config)
1765 return pinctrl_gpio_set_config(gc->gpiodev->base + offset, config);
1767 EXPORT_SYMBOL_GPL(gpiochip_generic_config);
1769 #ifdef CONFIG_PINCTRL
1772 * gpiochip_add_pingroup_range() - add a range for GPIO <-> pin mapping
1773 * @gc: the gpiochip to add the range for
1774 * @pctldev: the pin controller to map to
1775 * @gpio_offset: the start offset in the current gpio_chip number space
1776 * @pin_group: name of the pin group inside the pin controller
1778 * Calling this function directly from a DeviceTree-supported
1779 * pinctrl driver is DEPRECATED. Please see Section 2.1 of
1780 * Documentation/devicetree/bindings/gpio/gpio.txt on how to
1781 * bind pinctrl and gpio drivers via the "gpio-ranges" property.
1783 int gpiochip_add_pingroup_range(struct gpio_chip *gc,
1784 struct pinctrl_dev *pctldev,
1785 unsigned int gpio_offset, const char *pin_group)
1787 struct gpio_pin_range *pin_range;
1788 struct gpio_device *gdev = gc->gpiodev;
1791 pin_range = kzalloc(sizeof(*pin_range), GFP_KERNEL);
1793 chip_err(gc, "failed to allocate pin ranges\n");
1797 /* Use local offset as range ID */
1798 pin_range->range.id = gpio_offset;
1799 pin_range->range.gc = gc;
1800 pin_range->range.name = gc->label;
1801 pin_range->range.base = gdev->base + gpio_offset;
1802 pin_range->pctldev = pctldev;
1804 ret = pinctrl_get_group_pins(pctldev, pin_group,
1805 &pin_range->range.pins,
1806 &pin_range->range.npins);
1812 pinctrl_add_gpio_range(pctldev, &pin_range->range);
1814 chip_dbg(gc, "created GPIO range %d->%d ==> %s PINGRP %s\n",
1815 gpio_offset, gpio_offset + pin_range->range.npins - 1,
1816 pinctrl_dev_get_devname(pctldev), pin_group);
1818 list_add_tail(&pin_range->node, &gdev->pin_ranges);
1822 EXPORT_SYMBOL_GPL(gpiochip_add_pingroup_range);
1825 * gpiochip_add_pin_range() - add a range for GPIO <-> pin mapping
1826 * @gc: the gpiochip to add the range for
1827 * @pinctl_name: the dev_name() of the pin controller to map to
1828 * @gpio_offset: the start offset in the current gpio_chip number space
1829 * @pin_offset: the start offset in the pin controller number space
1830 * @npins: the number of pins from the offset of each pin space (GPIO and
1831 * pin controller) to accumulate in this range
1834 * 0 on success, or a negative error-code on failure.
1836 * Calling this function directly from a DeviceTree-supported
1837 * pinctrl driver is DEPRECATED. Please see Section 2.1 of
1838 * Documentation/devicetree/bindings/gpio/gpio.txt on how to
1839 * bind pinctrl and gpio drivers via the "gpio-ranges" property.
1841 int gpiochip_add_pin_range(struct gpio_chip *gc, const char *pinctl_name,
1842 unsigned int gpio_offset, unsigned int pin_offset,
1845 struct gpio_pin_range *pin_range;
1846 struct gpio_device *gdev = gc->gpiodev;
1849 pin_range = kzalloc(sizeof(*pin_range), GFP_KERNEL);
1851 chip_err(gc, "failed to allocate pin ranges\n");
1855 /* Use local offset as range ID */
1856 pin_range->range.id = gpio_offset;
1857 pin_range->range.gc = gc;
1858 pin_range->range.name = gc->label;
1859 pin_range->range.base = gdev->base + gpio_offset;
1860 pin_range->range.pin_base = pin_offset;
1861 pin_range->range.npins = npins;
1862 pin_range->pctldev = pinctrl_find_and_add_gpio_range(pinctl_name,
1864 if (IS_ERR(pin_range->pctldev)) {
1865 ret = PTR_ERR(pin_range->pctldev);
1866 chip_err(gc, "could not create pin range\n");
1870 chip_dbg(gc, "created GPIO range %d->%d ==> %s PIN %d->%d\n",
1871 gpio_offset, gpio_offset + npins - 1,
1873 pin_offset, pin_offset + npins - 1);
1875 list_add_tail(&pin_range->node, &gdev->pin_ranges);
1879 EXPORT_SYMBOL_GPL(gpiochip_add_pin_range);
1882 * gpiochip_remove_pin_ranges() - remove all the GPIO <-> pin mappings
1883 * @gc: the chip to remove all the mappings for
1885 void gpiochip_remove_pin_ranges(struct gpio_chip *gc)
1887 struct gpio_pin_range *pin_range, *tmp;
1888 struct gpio_device *gdev = gc->gpiodev;
1890 list_for_each_entry_safe(pin_range, tmp, &gdev->pin_ranges, node) {
1891 list_del(&pin_range->node);
1892 pinctrl_remove_gpio_range(pin_range->pctldev,
1897 EXPORT_SYMBOL_GPL(gpiochip_remove_pin_ranges);
1899 #endif /* CONFIG_PINCTRL */
1901 /* These "optional" allocation calls help prevent drivers from stomping
1902 * on each other, and help provide better diagnostics in debugfs.
1903 * They're called even less than the "set direction" calls.
1905 static int gpiod_request_commit(struct gpio_desc *desc, const char *label)
1907 struct gpio_chip *gc = desc->gdev->chip;
1909 unsigned long flags;
1913 label = kstrdup_const(label, GFP_KERNEL);
1918 spin_lock_irqsave(&gpio_lock, flags);
1920 /* NOTE: gpio_request() can be called in early boot,
1921 * before IRQs are enabled, for non-sleeping (SOC) GPIOs.
1924 if (test_and_set_bit(FLAG_REQUESTED, &desc->flags) == 0) {
1925 desc_set_label(desc, label ? : "?");
1928 goto out_free_unlock;
1932 /* gc->request may sleep */
1933 spin_unlock_irqrestore(&gpio_lock, flags);
1934 offset = gpio_chip_hwgpio(desc);
1935 if (gpiochip_line_is_valid(gc, offset))
1936 ret = gc->request(gc, offset);
1939 spin_lock_irqsave(&gpio_lock, flags);
1942 desc_set_label(desc, NULL);
1943 clear_bit(FLAG_REQUESTED, &desc->flags);
1944 goto out_free_unlock;
1947 if (gc->get_direction) {
1948 /* gc->get_direction may sleep */
1949 spin_unlock_irqrestore(&gpio_lock, flags);
1950 gpiod_get_direction(desc);
1951 spin_lock_irqsave(&gpio_lock, flags);
1953 spin_unlock_irqrestore(&gpio_lock, flags);
1957 spin_unlock_irqrestore(&gpio_lock, flags);
1963 * This descriptor validation needs to be inserted verbatim into each
1964 * function taking a descriptor, so we need to use a preprocessor
1965 * macro to avoid endless duplication. If the desc is NULL it is an
1966 * optional GPIO and calls should just bail out.
1968 static int validate_desc(const struct gpio_desc *desc, const char *func)
1973 pr_warn("%s: invalid GPIO (errorpointer)\n", func);
1974 return PTR_ERR(desc);
1977 pr_warn("%s: invalid GPIO (no device)\n", func);
1980 if (!desc->gdev->chip) {
1981 dev_warn(&desc->gdev->dev,
1982 "%s: backing chip is gone\n", func);
1988 #define VALIDATE_DESC(desc) do { \
1989 int __valid = validate_desc(desc, __func__); \
1994 #define VALIDATE_DESC_VOID(desc) do { \
1995 int __valid = validate_desc(desc, __func__); \
2000 int gpiod_request(struct gpio_desc *desc, const char *label)
2002 int ret = -EPROBE_DEFER;
2003 struct gpio_device *gdev;
2005 VALIDATE_DESC(desc);
2008 if (try_module_get(gdev->owner)) {
2009 ret = gpiod_request_commit(desc, label);
2011 module_put(gdev->owner);
2013 get_device(&gdev->dev);
2017 gpiod_dbg(desc, "%s: status %d\n", __func__, ret);
2022 static bool gpiod_free_commit(struct gpio_desc *desc)
2025 unsigned long flags;
2026 struct gpio_chip *gc;
2030 gpiod_unexport(desc);
2032 spin_lock_irqsave(&gpio_lock, flags);
2034 gc = desc->gdev->chip;
2035 if (gc && test_bit(FLAG_REQUESTED, &desc->flags)) {
2037 spin_unlock_irqrestore(&gpio_lock, flags);
2038 might_sleep_if(gc->can_sleep);
2039 gc->free(gc, gpio_chip_hwgpio(desc));
2040 spin_lock_irqsave(&gpio_lock, flags);
2042 kfree_const(desc->label);
2043 desc_set_label(desc, NULL);
2044 clear_bit(FLAG_ACTIVE_LOW, &desc->flags);
2045 clear_bit(FLAG_REQUESTED, &desc->flags);
2046 clear_bit(FLAG_OPEN_DRAIN, &desc->flags);
2047 clear_bit(FLAG_OPEN_SOURCE, &desc->flags);
2048 clear_bit(FLAG_PULL_UP, &desc->flags);
2049 clear_bit(FLAG_PULL_DOWN, &desc->flags);
2050 clear_bit(FLAG_BIAS_DISABLE, &desc->flags);
2051 clear_bit(FLAG_EDGE_RISING, &desc->flags);
2052 clear_bit(FLAG_EDGE_FALLING, &desc->flags);
2053 clear_bit(FLAG_IS_HOGGED, &desc->flags);
2054 #ifdef CONFIG_OF_DYNAMIC
2057 #ifdef CONFIG_GPIO_CDEV
2058 WRITE_ONCE(desc->debounce_period_us, 0);
2063 spin_unlock_irqrestore(&gpio_lock, flags);
2064 blocking_notifier_call_chain(&desc->gdev->notifier,
2065 GPIOLINE_CHANGED_RELEASED, desc);
2070 void gpiod_free(struct gpio_desc *desc)
2072 if (desc && desc->gdev && gpiod_free_commit(desc)) {
2073 module_put(desc->gdev->owner);
2074 put_device(&desc->gdev->dev);
2076 WARN_ON(extra_checks);
2081 * gpiochip_is_requested - return string iff signal was requested
2082 * @gc: controller managing the signal
2083 * @offset: of signal within controller's 0..(ngpio - 1) range
2085 * Returns NULL if the GPIO is not currently requested, else a string.
2086 * The string returned is the label passed to gpio_request(); if none has been
2087 * passed it is a meaningless, non-NULL constant.
2089 * This function is for use by GPIO controller drivers. The label can
2090 * help with diagnostics, and knowing that the signal is used as a GPIO
2091 * can help avoid accidentally multiplexing it to another controller.
2093 const char *gpiochip_is_requested(struct gpio_chip *gc, unsigned int offset)
2095 struct gpio_desc *desc;
2097 desc = gpiochip_get_desc(gc, offset);
2101 if (test_bit(FLAG_REQUESTED, &desc->flags) == 0)
2105 EXPORT_SYMBOL_GPL(gpiochip_is_requested);
2108 * gpiochip_request_own_desc - Allow GPIO chip to request its own descriptor
2110 * @hwnum: hardware number of the GPIO for which to request the descriptor
2111 * @label: label for the GPIO
2112 * @lflags: lookup flags for this GPIO or 0 if default, this can be used to
2113 * specify things like line inversion semantics with the machine flags
2114 * such as GPIO_OUT_LOW
2115 * @dflags: descriptor request flags for this GPIO or 0 if default, this
2116 * can be used to specify consumer semantics such as open drain
2118 * Function allows GPIO chip drivers to request and use their own GPIO
2119 * descriptors via gpiolib API. Difference to gpiod_request() is that this
2120 * function will not increase reference count of the GPIO chip module. This
2121 * allows the GPIO chip module to be unloaded as needed (we assume that the
2122 * GPIO chip driver handles freeing the GPIOs it has requested).
2125 * A pointer to the GPIO descriptor, or an ERR_PTR()-encoded negative error
2128 struct gpio_desc *gpiochip_request_own_desc(struct gpio_chip *gc,
2131 enum gpio_lookup_flags lflags,
2132 enum gpiod_flags dflags)
2134 struct gpio_desc *desc = gpiochip_get_desc(gc, hwnum);
2138 chip_err(gc, "failed to get GPIO descriptor\n");
2142 ret = gpiod_request_commit(desc, label);
2144 return ERR_PTR(ret);
2146 ret = gpiod_configure_flags(desc, label, lflags, dflags);
2148 chip_err(gc, "setup of own GPIO %s failed\n", label);
2149 gpiod_free_commit(desc);
2150 return ERR_PTR(ret);
2155 EXPORT_SYMBOL_GPL(gpiochip_request_own_desc);
2158 * gpiochip_free_own_desc - Free GPIO requested by the chip driver
2159 * @desc: GPIO descriptor to free
2161 * Function frees the given GPIO requested previously with
2162 * gpiochip_request_own_desc().
2164 void gpiochip_free_own_desc(struct gpio_desc *desc)
2167 gpiod_free_commit(desc);
2169 EXPORT_SYMBOL_GPL(gpiochip_free_own_desc);
2172 * Drivers MUST set GPIO direction before making get/set calls. In
2173 * some cases this is done in early boot, before IRQs are enabled.
2175 * As a rule these aren't called more than once (except for drivers
2176 * using the open-drain emulation idiom) so these are natural places
2177 * to accumulate extra debugging checks. Note that we can't (yet)
2178 * rely on gpio_request() having been called beforehand.
2181 static int gpio_do_set_config(struct gpio_chip *gc, unsigned int offset,
2182 unsigned long config)
2184 if (!gc->set_config)
2187 return gc->set_config(gc, offset, config);
2190 static int gpio_set_config_with_argument(struct gpio_desc *desc,
2191 enum pin_config_param mode,
2194 struct gpio_chip *gc = desc->gdev->chip;
2195 unsigned long config;
2197 config = pinconf_to_config_packed(mode, argument);
2198 return gpio_do_set_config(gc, gpio_chip_hwgpio(desc), config);
2201 static int gpio_set_config_with_argument_optional(struct gpio_desc *desc,
2202 enum pin_config_param mode,
2205 struct device *dev = &desc->gdev->dev;
2206 int gpio = gpio_chip_hwgpio(desc);
2209 ret = gpio_set_config_with_argument(desc, mode, argument);
2210 if (ret != -ENOTSUPP)
2214 case PIN_CONFIG_PERSIST_STATE:
2215 dev_dbg(dev, "Persistence not supported for GPIO %d\n", gpio);
2224 static int gpio_set_config(struct gpio_desc *desc, enum pin_config_param mode)
2226 return gpio_set_config_with_argument(desc, mode, 0);
2229 static int gpio_set_bias(struct gpio_desc *desc)
2231 enum pin_config_param bias;
2234 if (test_bit(FLAG_BIAS_DISABLE, &desc->flags))
2235 bias = PIN_CONFIG_BIAS_DISABLE;
2236 else if (test_bit(FLAG_PULL_UP, &desc->flags))
2237 bias = PIN_CONFIG_BIAS_PULL_UP;
2238 else if (test_bit(FLAG_PULL_DOWN, &desc->flags))
2239 bias = PIN_CONFIG_BIAS_PULL_DOWN;
2244 case PIN_CONFIG_BIAS_PULL_DOWN:
2245 case PIN_CONFIG_BIAS_PULL_UP:
2254 return gpio_set_config_with_argument_optional(desc, bias, arg);
2258 * gpio_set_debounce_timeout() - Set debounce timeout
2259 * @desc: GPIO descriptor to set the debounce timeout
2260 * @debounce: Debounce timeout in microseconds
2262 * The function calls the certain GPIO driver to set debounce timeout
2265 * Returns 0 on success, or negative error code otherwise.
2267 int gpio_set_debounce_timeout(struct gpio_desc *desc, unsigned int debounce)
2269 return gpio_set_config_with_argument_optional(desc,
2270 PIN_CONFIG_INPUT_DEBOUNCE,
2275 * gpiod_direction_input - set the GPIO direction to input
2276 * @desc: GPIO to set to input
2278 * Set the direction of the passed GPIO to input, such as gpiod_get_value() can
2279 * be called safely on it.
2281 * Return 0 in case of success, else an error code.
2283 int gpiod_direction_input(struct gpio_desc *desc)
2285 struct gpio_chip *gc;
2288 VALIDATE_DESC(desc);
2289 gc = desc->gdev->chip;
2292 * It is legal to have no .get() and .direction_input() specified if
2293 * the chip is output-only, but you can't specify .direction_input()
2294 * and not support the .get() operation, that doesn't make sense.
2296 if (!gc->get && gc->direction_input) {
2298 "%s: missing get() but have direction_input()\n",
2304 * If we have a .direction_input() callback, things are simple,
2305 * just call it. Else we are some input-only chip so try to check the
2306 * direction (if .get_direction() is supported) else we silently
2307 * assume we are in input mode after this.
2309 if (gc->direction_input) {
2310 ret = gc->direction_input(gc, gpio_chip_hwgpio(desc));
2311 } else if (gc->get_direction &&
2312 (gc->get_direction(gc, gpio_chip_hwgpio(desc)) != 1)) {
2314 "%s: missing direction_input() operation and line is output\n",
2319 clear_bit(FLAG_IS_OUT, &desc->flags);
2320 ret = gpio_set_bias(desc);
2323 trace_gpio_direction(desc_to_gpio(desc), 1, ret);
2327 EXPORT_SYMBOL_GPL(gpiod_direction_input);
2329 static int gpiod_direction_output_raw_commit(struct gpio_desc *desc, int value)
2331 struct gpio_chip *gc = desc->gdev->chip;
2336 * It's OK not to specify .direction_output() if the gpiochip is
2337 * output-only, but if there is then not even a .set() operation it
2338 * is pretty tricky to drive the output line.
2340 if (!gc->set && !gc->direction_output) {
2342 "%s: missing set() and direction_output() operations\n",
2347 if (gc->direction_output) {
2348 ret = gc->direction_output(gc, gpio_chip_hwgpio(desc), val);
2350 /* Check that we are in output mode if we can */
2351 if (gc->get_direction &&
2352 gc->get_direction(gc, gpio_chip_hwgpio(desc))) {
2354 "%s: missing direction_output() operation\n",
2359 * If we can't actively set the direction, we are some
2360 * output-only chip, so just drive the output as desired.
2362 gc->set(gc, gpio_chip_hwgpio(desc), val);
2366 set_bit(FLAG_IS_OUT, &desc->flags);
2367 trace_gpio_value(desc_to_gpio(desc), 0, val);
2368 trace_gpio_direction(desc_to_gpio(desc), 0, ret);
2373 * gpiod_direction_output_raw - set the GPIO direction to output
2374 * @desc: GPIO to set to output
2375 * @value: initial output value of the GPIO
2377 * Set the direction of the passed GPIO to output, such as gpiod_set_value() can
2378 * be called safely on it. The initial value of the output must be specified
2379 * as raw value on the physical line without regard for the ACTIVE_LOW status.
2381 * Return 0 in case of success, else an error code.
2383 int gpiod_direction_output_raw(struct gpio_desc *desc, int value)
2385 VALIDATE_DESC(desc);
2386 return gpiod_direction_output_raw_commit(desc, value);
2388 EXPORT_SYMBOL_GPL(gpiod_direction_output_raw);
2391 * gpiod_direction_output - set the GPIO direction to output
2392 * @desc: GPIO to set to output
2393 * @value: initial output value of the GPIO
2395 * Set the direction of the passed GPIO to output, such as gpiod_set_value() can
2396 * be called safely on it. The initial value of the output must be specified
2397 * as the logical value of the GPIO, i.e. taking its ACTIVE_LOW status into
2400 * Return 0 in case of success, else an error code.
2402 int gpiod_direction_output(struct gpio_desc *desc, int value)
2406 VALIDATE_DESC(desc);
2407 if (test_bit(FLAG_ACTIVE_LOW, &desc->flags))
2412 /* GPIOs used for enabled IRQs shall not be set as output */
2413 if (test_bit(FLAG_USED_AS_IRQ, &desc->flags) &&
2414 test_bit(FLAG_IRQ_IS_ENABLED, &desc->flags)) {
2416 "%s: tried to set a GPIO tied to an IRQ as output\n",
2421 if (test_bit(FLAG_OPEN_DRAIN, &desc->flags)) {
2422 /* First see if we can enable open drain in hardware */
2423 ret = gpio_set_config(desc, PIN_CONFIG_DRIVE_OPEN_DRAIN);
2425 goto set_output_value;
2426 /* Emulate open drain by not actively driving the line high */
2428 ret = gpiod_direction_input(desc);
2429 goto set_output_flag;
2431 } else if (test_bit(FLAG_OPEN_SOURCE, &desc->flags)) {
2432 ret = gpio_set_config(desc, PIN_CONFIG_DRIVE_OPEN_SOURCE);
2434 goto set_output_value;
2435 /* Emulate open source by not actively driving the line low */
2437 ret = gpiod_direction_input(desc);
2438 goto set_output_flag;
2441 gpio_set_config(desc, PIN_CONFIG_DRIVE_PUSH_PULL);
2445 ret = gpio_set_bias(desc);
2448 return gpiod_direction_output_raw_commit(desc, value);
2452 * When emulating open-source or open-drain functionalities by not
2453 * actively driving the line (setting mode to input) we still need to
2454 * set the IS_OUT flag or otherwise we won't be able to set the line
2458 set_bit(FLAG_IS_OUT, &desc->flags);
2461 EXPORT_SYMBOL_GPL(gpiod_direction_output);
2464 * gpiod_enable_hw_timestamp_ns - Enable hardware timestamp in nanoseconds.
2466 * @desc: GPIO to enable.
2467 * @flags: Flags related to GPIO edge.
2469 * Return 0 in case of success, else negative error code.
2471 int gpiod_enable_hw_timestamp_ns(struct gpio_desc *desc, unsigned long flags)
2474 struct gpio_chip *gc;
2476 VALIDATE_DESC(desc);
2478 gc = desc->gdev->chip;
2479 if (!gc->en_hw_timestamp) {
2480 gpiod_warn(desc, "%s: hw ts not supported\n", __func__);
2484 ret = gc->en_hw_timestamp(gc, gpio_chip_hwgpio(desc), flags);
2486 gpiod_warn(desc, "%s: hw ts request failed\n", __func__);
2490 EXPORT_SYMBOL_GPL(gpiod_enable_hw_timestamp_ns);
2493 * gpiod_disable_hw_timestamp_ns - Disable hardware timestamp.
2495 * @desc: GPIO to disable.
2496 * @flags: Flags related to GPIO edge, same value as used during enable call.
2498 * Return 0 in case of success, else negative error code.
2500 int gpiod_disable_hw_timestamp_ns(struct gpio_desc *desc, unsigned long flags)
2503 struct gpio_chip *gc;
2505 VALIDATE_DESC(desc);
2507 gc = desc->gdev->chip;
2508 if (!gc->dis_hw_timestamp) {
2509 gpiod_warn(desc, "%s: hw ts not supported\n", __func__);
2513 ret = gc->dis_hw_timestamp(gc, gpio_chip_hwgpio(desc), flags);
2515 gpiod_warn(desc, "%s: hw ts release failed\n", __func__);
2519 EXPORT_SYMBOL_GPL(gpiod_disable_hw_timestamp_ns);
2522 * gpiod_set_config - sets @config for a GPIO
2523 * @desc: descriptor of the GPIO for which to set the configuration
2524 * @config: Same packed config format as generic pinconf
2527 * 0 on success, %-ENOTSUPP if the controller doesn't support setting the
2530 int gpiod_set_config(struct gpio_desc *desc, unsigned long config)
2532 struct gpio_chip *gc;
2534 VALIDATE_DESC(desc);
2535 gc = desc->gdev->chip;
2537 return gpio_do_set_config(gc, gpio_chip_hwgpio(desc), config);
2539 EXPORT_SYMBOL_GPL(gpiod_set_config);
2542 * gpiod_set_debounce - sets @debounce time for a GPIO
2543 * @desc: descriptor of the GPIO for which to set debounce time
2544 * @debounce: debounce time in microseconds
2547 * 0 on success, %-ENOTSUPP if the controller doesn't support setting the
2550 int gpiod_set_debounce(struct gpio_desc *desc, unsigned int debounce)
2552 unsigned long config;
2554 config = pinconf_to_config_packed(PIN_CONFIG_INPUT_DEBOUNCE, debounce);
2555 return gpiod_set_config(desc, config);
2557 EXPORT_SYMBOL_GPL(gpiod_set_debounce);
2560 * gpiod_set_transitory - Lose or retain GPIO state on suspend or reset
2561 * @desc: descriptor of the GPIO for which to configure persistence
2562 * @transitory: True to lose state on suspend or reset, false for persistence
2565 * 0 on success, otherwise a negative error code.
2567 int gpiod_set_transitory(struct gpio_desc *desc, bool transitory)
2569 VALIDATE_DESC(desc);
2571 * Handle FLAG_TRANSITORY first, enabling queries to gpiolib for
2572 * persistence state.
2574 assign_bit(FLAG_TRANSITORY, &desc->flags, transitory);
2576 /* If the driver supports it, set the persistence state now */
2577 return gpio_set_config_with_argument_optional(desc,
2578 PIN_CONFIG_PERSIST_STATE,
2581 EXPORT_SYMBOL_GPL(gpiod_set_transitory);
2584 * gpiod_is_active_low - test whether a GPIO is active-low or not
2585 * @desc: the gpio descriptor to test
2587 * Returns 1 if the GPIO is active-low, 0 otherwise.
2589 int gpiod_is_active_low(const struct gpio_desc *desc)
2591 VALIDATE_DESC(desc);
2592 return test_bit(FLAG_ACTIVE_LOW, &desc->flags);
2594 EXPORT_SYMBOL_GPL(gpiod_is_active_low);
2597 * gpiod_toggle_active_low - toggle whether a GPIO is active-low or not
2598 * @desc: the gpio descriptor to change
2600 void gpiod_toggle_active_low(struct gpio_desc *desc)
2602 VALIDATE_DESC_VOID(desc);
2603 change_bit(FLAG_ACTIVE_LOW, &desc->flags);
2605 EXPORT_SYMBOL_GPL(gpiod_toggle_active_low);
2607 static int gpio_chip_get_value(struct gpio_chip *gc, const struct gpio_desc *desc)
2609 return gc->get ? gc->get(gc, gpio_chip_hwgpio(desc)) : -EIO;
2612 /* I/O calls are only valid after configuration completed; the relevant
2613 * "is this a valid GPIO" error checks should already have been done.
2615 * "Get" operations are often inlinable as reading a pin value register,
2616 * and masking the relevant bit in that register.
2618 * When "set" operations are inlinable, they involve writing that mask to
2619 * one register to set a low value, or a different register to set it high.
2620 * Otherwise locking is needed, so there may be little value to inlining.
2622 *------------------------------------------------------------------------
2624 * IMPORTANT!!! The hot paths -- get/set value -- assume that callers
2625 * have requested the GPIO. That can include implicit requesting by
2626 * a direction setting call. Marking a gpio as requested locks its chip
2627 * in memory, guaranteeing that these table lookups need no more locking
2628 * and that gpiochip_remove() will fail.
2630 * REVISIT when debugging, consider adding some instrumentation to ensure
2631 * that the GPIO was actually requested.
2634 static int gpiod_get_raw_value_commit(const struct gpio_desc *desc)
2636 struct gpio_chip *gc;
2639 gc = desc->gdev->chip;
2640 value = gpio_chip_get_value(gc, desc);
2641 value = value < 0 ? value : !!value;
2642 trace_gpio_value(desc_to_gpio(desc), 1, value);
2646 static int gpio_chip_get_multiple(struct gpio_chip *gc,
2647 unsigned long *mask, unsigned long *bits)
2649 if (gc->get_multiple)
2650 return gc->get_multiple(gc, mask, bits);
2654 for_each_set_bit(i, mask, gc->ngpio) {
2655 value = gc->get(gc, i);
2658 __assign_bit(i, bits, value);
2665 int gpiod_get_array_value_complex(bool raw, bool can_sleep,
2666 unsigned int array_size,
2667 struct gpio_desc **desc_array,
2668 struct gpio_array *array_info,
2669 unsigned long *value_bitmap)
2674 * Validate array_info against desc_array and its size.
2675 * It should immediately follow desc_array if both
2676 * have been obtained from the same gpiod_get_array() call.
2678 if (array_info && array_info->desc == desc_array &&
2679 array_size <= array_info->size &&
2680 (void *)array_info == desc_array + array_info->size) {
2682 WARN_ON(array_info->chip->can_sleep);
2684 ret = gpio_chip_get_multiple(array_info->chip,
2685 array_info->get_mask,
2690 if (!raw && !bitmap_empty(array_info->invert_mask, array_size))
2691 bitmap_xor(value_bitmap, value_bitmap,
2692 array_info->invert_mask, array_size);
2694 i = find_first_zero_bit(array_info->get_mask, array_size);
2695 if (i == array_size)
2701 while (i < array_size) {
2702 struct gpio_chip *gc = desc_array[i]->gdev->chip;
2703 DECLARE_BITMAP(fastpath_mask, FASTPATH_NGPIO);
2704 DECLARE_BITMAP(fastpath_bits, FASTPATH_NGPIO);
2705 unsigned long *mask, *bits;
2708 if (likely(gc->ngpio <= FASTPATH_NGPIO)) {
2709 mask = fastpath_mask;
2710 bits = fastpath_bits;
2712 gfp_t flags = can_sleep ? GFP_KERNEL : GFP_ATOMIC;
2714 mask = bitmap_alloc(gc->ngpio, flags);
2718 bits = bitmap_alloc(gc->ngpio, flags);
2725 bitmap_zero(mask, gc->ngpio);
2728 WARN_ON(gc->can_sleep);
2730 /* collect all inputs belonging to the same chip */
2733 const struct gpio_desc *desc = desc_array[i];
2734 int hwgpio = gpio_chip_hwgpio(desc);
2736 __set_bit(hwgpio, mask);
2740 i = find_next_zero_bit(array_info->get_mask,
2742 } while ((i < array_size) &&
2743 (desc_array[i]->gdev->chip == gc));
2745 ret = gpio_chip_get_multiple(gc, mask, bits);
2747 if (mask != fastpath_mask)
2749 if (bits != fastpath_bits)
2754 for (j = first; j < i; ) {
2755 const struct gpio_desc *desc = desc_array[j];
2756 int hwgpio = gpio_chip_hwgpio(desc);
2757 int value = test_bit(hwgpio, bits);
2759 if (!raw && test_bit(FLAG_ACTIVE_LOW, &desc->flags))
2761 __assign_bit(j, value_bitmap, value);
2762 trace_gpio_value(desc_to_gpio(desc), 1, value);
2766 j = find_next_zero_bit(array_info->get_mask, i,
2770 if (mask != fastpath_mask)
2772 if (bits != fastpath_bits)
2779 * gpiod_get_raw_value() - return a gpio's raw value
2780 * @desc: gpio whose value will be returned
2782 * Return the GPIO's raw value, i.e. the value of the physical line disregarding
2783 * its ACTIVE_LOW status, or negative errno on failure.
2785 * This function can be called from contexts where we cannot sleep, and will
2786 * complain if the GPIO chip functions potentially sleep.
2788 int gpiod_get_raw_value(const struct gpio_desc *desc)
2790 VALIDATE_DESC(desc);
2791 /* Should be using gpiod_get_raw_value_cansleep() */
2792 WARN_ON(desc->gdev->chip->can_sleep);
2793 return gpiod_get_raw_value_commit(desc);
2795 EXPORT_SYMBOL_GPL(gpiod_get_raw_value);
2798 * gpiod_get_value() - return a gpio's value
2799 * @desc: gpio whose value will be returned
2801 * Return the GPIO's logical value, i.e. taking the ACTIVE_LOW status into
2802 * account, or negative errno on failure.
2804 * This function can be called from contexts where we cannot sleep, and will
2805 * complain if the GPIO chip functions potentially sleep.
2807 int gpiod_get_value(const struct gpio_desc *desc)
2811 VALIDATE_DESC(desc);
2812 /* Should be using gpiod_get_value_cansleep() */
2813 WARN_ON(desc->gdev->chip->can_sleep);
2815 value = gpiod_get_raw_value_commit(desc);
2819 if (test_bit(FLAG_ACTIVE_LOW, &desc->flags))
2824 EXPORT_SYMBOL_GPL(gpiod_get_value);
2827 * gpiod_get_raw_array_value() - read raw values from an array of GPIOs
2828 * @array_size: number of elements in the descriptor array / value bitmap
2829 * @desc_array: array of GPIO descriptors whose values will be read
2830 * @array_info: information on applicability of fast bitmap processing path
2831 * @value_bitmap: bitmap to store the read values
2833 * Read the raw values of the GPIOs, i.e. the values of the physical lines
2834 * without regard for their ACTIVE_LOW status. Return 0 in case of success,
2835 * else an error code.
2837 * This function can be called from contexts where we cannot sleep,
2838 * and it will complain if the GPIO chip functions potentially sleep.
2840 int gpiod_get_raw_array_value(unsigned int array_size,
2841 struct gpio_desc **desc_array,
2842 struct gpio_array *array_info,
2843 unsigned long *value_bitmap)
2847 return gpiod_get_array_value_complex(true, false, array_size,
2848 desc_array, array_info,
2851 EXPORT_SYMBOL_GPL(gpiod_get_raw_array_value);
2854 * gpiod_get_array_value() - read values from an array of GPIOs
2855 * @array_size: number of elements in the descriptor array / value bitmap
2856 * @desc_array: array of GPIO descriptors whose values will be read
2857 * @array_info: information on applicability of fast bitmap processing path
2858 * @value_bitmap: bitmap to store the read values
2860 * Read the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status
2861 * into account. Return 0 in case of success, else an error code.
2863 * This function can be called from contexts where we cannot sleep,
2864 * and it will complain if the GPIO chip functions potentially sleep.
2866 int gpiod_get_array_value(unsigned int array_size,
2867 struct gpio_desc **desc_array,
2868 struct gpio_array *array_info,
2869 unsigned long *value_bitmap)
2873 return gpiod_get_array_value_complex(false, false, array_size,
2874 desc_array, array_info,
2877 EXPORT_SYMBOL_GPL(gpiod_get_array_value);
2880 * gpio_set_open_drain_value_commit() - Set the open drain gpio's value.
2881 * @desc: gpio descriptor whose state need to be set.
2882 * @value: Non-zero for setting it HIGH otherwise it will set to LOW.
2884 static void gpio_set_open_drain_value_commit(struct gpio_desc *desc, bool value)
2887 struct gpio_chip *gc = desc->gdev->chip;
2888 int offset = gpio_chip_hwgpio(desc);
2891 ret = gc->direction_input(gc, offset);
2893 ret = gc->direction_output(gc, offset, 0);
2895 set_bit(FLAG_IS_OUT, &desc->flags);
2897 trace_gpio_direction(desc_to_gpio(desc), value, ret);
2900 "%s: Error in set_value for open drain err %d\n",
2905 * _gpio_set_open_source_value() - Set the open source gpio's value.
2906 * @desc: gpio descriptor whose state need to be set.
2907 * @value: Non-zero for setting it HIGH otherwise it will set to LOW.
2909 static void gpio_set_open_source_value_commit(struct gpio_desc *desc, bool value)
2912 struct gpio_chip *gc = desc->gdev->chip;
2913 int offset = gpio_chip_hwgpio(desc);
2916 ret = gc->direction_output(gc, offset, 1);
2918 set_bit(FLAG_IS_OUT, &desc->flags);
2920 ret = gc->direction_input(gc, offset);
2922 trace_gpio_direction(desc_to_gpio(desc), !value, ret);
2925 "%s: Error in set_value for open source err %d\n",
2929 static void gpiod_set_raw_value_commit(struct gpio_desc *desc, bool value)
2931 struct gpio_chip *gc;
2933 gc = desc->gdev->chip;
2934 trace_gpio_value(desc_to_gpio(desc), 0, value);
2935 gc->set(gc, gpio_chip_hwgpio(desc), value);
2939 * set multiple outputs on the same chip;
2940 * use the chip's set_multiple function if available;
2941 * otherwise set the outputs sequentially;
2942 * @chip: the GPIO chip we operate on
2943 * @mask: bit mask array; one bit per output; BITS_PER_LONG bits per word
2944 * defines which outputs are to be changed
2945 * @bits: bit value array; one bit per output; BITS_PER_LONG bits per word
2946 * defines the values the outputs specified by mask are to be set to
2948 static void gpio_chip_set_multiple(struct gpio_chip *gc,
2949 unsigned long *mask, unsigned long *bits)
2951 if (gc->set_multiple) {
2952 gc->set_multiple(gc, mask, bits);
2956 /* set outputs if the corresponding mask bit is set */
2957 for_each_set_bit(i, mask, gc->ngpio)
2958 gc->set(gc, i, test_bit(i, bits));
2962 int gpiod_set_array_value_complex(bool raw, bool can_sleep,
2963 unsigned int array_size,
2964 struct gpio_desc **desc_array,
2965 struct gpio_array *array_info,
2966 unsigned long *value_bitmap)
2971 * Validate array_info against desc_array and its size.
2972 * It should immediately follow desc_array if both
2973 * have been obtained from the same gpiod_get_array() call.
2975 if (array_info && array_info->desc == desc_array &&
2976 array_size <= array_info->size &&
2977 (void *)array_info == desc_array + array_info->size) {
2979 WARN_ON(array_info->chip->can_sleep);
2981 if (!raw && !bitmap_empty(array_info->invert_mask, array_size))
2982 bitmap_xor(value_bitmap, value_bitmap,
2983 array_info->invert_mask, array_size);
2985 gpio_chip_set_multiple(array_info->chip, array_info->set_mask,
2988 i = find_first_zero_bit(array_info->set_mask, array_size);
2989 if (i == array_size)
2995 while (i < array_size) {
2996 struct gpio_chip *gc = desc_array[i]->gdev->chip;
2997 DECLARE_BITMAP(fastpath_mask, FASTPATH_NGPIO);
2998 DECLARE_BITMAP(fastpath_bits, FASTPATH_NGPIO);
2999 unsigned long *mask, *bits;
3002 if (likely(gc->ngpio <= FASTPATH_NGPIO)) {
3003 mask = fastpath_mask;
3004 bits = fastpath_bits;
3006 gfp_t flags = can_sleep ? GFP_KERNEL : GFP_ATOMIC;
3008 mask = bitmap_alloc(gc->ngpio, flags);
3012 bits = bitmap_alloc(gc->ngpio, flags);
3019 bitmap_zero(mask, gc->ngpio);
3022 WARN_ON(gc->can_sleep);
3025 struct gpio_desc *desc = desc_array[i];
3026 int hwgpio = gpio_chip_hwgpio(desc);
3027 int value = test_bit(i, value_bitmap);
3030 * Pins applicable for fast input but not for
3031 * fast output processing may have been already
3032 * inverted inside the fast path, skip them.
3034 if (!raw && !(array_info &&
3035 test_bit(i, array_info->invert_mask)) &&
3036 test_bit(FLAG_ACTIVE_LOW, &desc->flags))
3038 trace_gpio_value(desc_to_gpio(desc), 0, value);
3040 * collect all normal outputs belonging to the same chip
3041 * open drain and open source outputs are set individually
3043 if (test_bit(FLAG_OPEN_DRAIN, &desc->flags) && !raw) {
3044 gpio_set_open_drain_value_commit(desc, value);
3045 } else if (test_bit(FLAG_OPEN_SOURCE, &desc->flags) && !raw) {
3046 gpio_set_open_source_value_commit(desc, value);
3048 __set_bit(hwgpio, mask);
3049 __assign_bit(hwgpio, bits, value);
3055 i = find_next_zero_bit(array_info->set_mask,
3057 } while ((i < array_size) &&
3058 (desc_array[i]->gdev->chip == gc));
3059 /* push collected bits to outputs */
3061 gpio_chip_set_multiple(gc, mask, bits);
3063 if (mask != fastpath_mask)
3065 if (bits != fastpath_bits)
3072 * gpiod_set_raw_value() - assign a gpio's raw value
3073 * @desc: gpio whose value will be assigned
3074 * @value: value to assign
3076 * Set the raw value of the GPIO, i.e. the value of its physical line without
3077 * regard for its ACTIVE_LOW status.
3079 * This function can be called from contexts where we cannot sleep, and will
3080 * complain if the GPIO chip functions potentially sleep.
3082 void gpiod_set_raw_value(struct gpio_desc *desc, int value)
3084 VALIDATE_DESC_VOID(desc);
3085 /* Should be using gpiod_set_raw_value_cansleep() */
3086 WARN_ON(desc->gdev->chip->can_sleep);
3087 gpiod_set_raw_value_commit(desc, value);
3089 EXPORT_SYMBOL_GPL(gpiod_set_raw_value);
3092 * gpiod_set_value_nocheck() - set a GPIO line value without checking
3093 * @desc: the descriptor to set the value on
3094 * @value: value to set
3096 * This sets the value of a GPIO line backing a descriptor, applying
3097 * different semantic quirks like active low and open drain/source
3100 static void gpiod_set_value_nocheck(struct gpio_desc *desc, int value)
3102 if (test_bit(FLAG_ACTIVE_LOW, &desc->flags))
3104 if (test_bit(FLAG_OPEN_DRAIN, &desc->flags))
3105 gpio_set_open_drain_value_commit(desc, value);
3106 else if (test_bit(FLAG_OPEN_SOURCE, &desc->flags))
3107 gpio_set_open_source_value_commit(desc, value);
3109 gpiod_set_raw_value_commit(desc, value);
3113 * gpiod_set_value() - assign a gpio's value
3114 * @desc: gpio whose value will be assigned
3115 * @value: value to assign
3117 * Set the logical value of the GPIO, i.e. taking its ACTIVE_LOW,
3118 * OPEN_DRAIN and OPEN_SOURCE flags into account.
3120 * This function can be called from contexts where we cannot sleep, and will
3121 * complain if the GPIO chip functions potentially sleep.
3123 void gpiod_set_value(struct gpio_desc *desc, int value)
3125 VALIDATE_DESC_VOID(desc);
3126 /* Should be using gpiod_set_value_cansleep() */
3127 WARN_ON(desc->gdev->chip->can_sleep);
3128 gpiod_set_value_nocheck(desc, value);
3130 EXPORT_SYMBOL_GPL(gpiod_set_value);
3133 * gpiod_set_raw_array_value() - assign values to an array of GPIOs
3134 * @array_size: number of elements in the descriptor array / value bitmap
3135 * @desc_array: array of GPIO descriptors whose values will be assigned
3136 * @array_info: information on applicability of fast bitmap processing path
3137 * @value_bitmap: bitmap of values to assign
3139 * Set the raw values of the GPIOs, i.e. the values of the physical lines
3140 * without regard for their ACTIVE_LOW status.
3142 * This function can be called from contexts where we cannot sleep, and will
3143 * complain if the GPIO chip functions potentially sleep.
3145 int gpiod_set_raw_array_value(unsigned int array_size,
3146 struct gpio_desc **desc_array,
3147 struct gpio_array *array_info,
3148 unsigned long *value_bitmap)
3152 return gpiod_set_array_value_complex(true, false, array_size,
3153 desc_array, array_info, value_bitmap);
3155 EXPORT_SYMBOL_GPL(gpiod_set_raw_array_value);
3158 * gpiod_set_array_value() - assign values to an array of GPIOs
3159 * @array_size: number of elements in the descriptor array / value bitmap
3160 * @desc_array: array of GPIO descriptors whose values will be assigned
3161 * @array_info: information on applicability of fast bitmap processing path
3162 * @value_bitmap: bitmap of values to assign
3164 * Set the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status
3167 * This function can be called from contexts where we cannot sleep, and will
3168 * complain if the GPIO chip functions potentially sleep.
3170 int gpiod_set_array_value(unsigned int array_size,
3171 struct gpio_desc **desc_array,
3172 struct gpio_array *array_info,
3173 unsigned long *value_bitmap)
3177 return gpiod_set_array_value_complex(false, false, array_size,
3178 desc_array, array_info,
3181 EXPORT_SYMBOL_GPL(gpiod_set_array_value);
3184 * gpiod_cansleep() - report whether gpio value access may sleep
3185 * @desc: gpio to check
3188 int gpiod_cansleep(const struct gpio_desc *desc)
3190 VALIDATE_DESC(desc);
3191 return desc->gdev->chip->can_sleep;
3193 EXPORT_SYMBOL_GPL(gpiod_cansleep);
3196 * gpiod_set_consumer_name() - set the consumer name for the descriptor
3197 * @desc: gpio to set the consumer name on
3198 * @name: the new consumer name
3200 int gpiod_set_consumer_name(struct gpio_desc *desc, const char *name)
3202 VALIDATE_DESC(desc);
3204 name = kstrdup_const(name, GFP_KERNEL);
3209 kfree_const(desc->label);
3210 desc_set_label(desc, name);
3214 EXPORT_SYMBOL_GPL(gpiod_set_consumer_name);
3217 * gpiod_to_irq() - return the IRQ corresponding to a GPIO
3218 * @desc: gpio whose IRQ will be returned (already requested)
3220 * Return the IRQ corresponding to the passed GPIO, or an error code in case of
3223 int gpiod_to_irq(const struct gpio_desc *desc)
3225 struct gpio_chip *gc;
3229 * Cannot VALIDATE_DESC() here as gpiod_to_irq() consumer semantics
3230 * requires this function to not return zero on an invalid descriptor
3231 * but rather a negative error number.
3233 if (!desc || IS_ERR(desc) || !desc->gdev || !desc->gdev->chip)
3236 gc = desc->gdev->chip;
3237 offset = gpio_chip_hwgpio(desc);
3239 int retirq = gc->to_irq(gc, offset);
3241 /* Zero means NO_IRQ */
3247 #ifdef CONFIG_GPIOLIB_IRQCHIP
3250 * Avoid race condition with other code, which tries to lookup
3251 * an IRQ before the irqchip has been properly registered,
3252 * i.e. while gpiochip is still being brought up.
3254 return -EPROBE_DEFER;
3259 EXPORT_SYMBOL_GPL(gpiod_to_irq);
3262 * gpiochip_lock_as_irq() - lock a GPIO to be used as IRQ
3263 * @gc: the chip the GPIO to lock belongs to
3264 * @offset: the offset of the GPIO to lock as IRQ
3266 * This is used directly by GPIO drivers that want to lock down
3267 * a certain GPIO line to be used for IRQs.
3269 int gpiochip_lock_as_irq(struct gpio_chip *gc, unsigned int offset)
3271 struct gpio_desc *desc;
3273 desc = gpiochip_get_desc(gc, offset);
3275 return PTR_ERR(desc);
3278 * If it's fast: flush the direction setting if something changed
3281 if (!gc->can_sleep && gc->get_direction) {
3282 int dir = gpiod_get_direction(desc);
3285 chip_err(gc, "%s: cannot get GPIO direction\n",
3291 /* To be valid for IRQ the line needs to be input or open drain */
3292 if (test_bit(FLAG_IS_OUT, &desc->flags) &&
3293 !test_bit(FLAG_OPEN_DRAIN, &desc->flags)) {
3295 "%s: tried to flag a GPIO set as output for IRQ\n",
3300 set_bit(FLAG_USED_AS_IRQ, &desc->flags);
3301 set_bit(FLAG_IRQ_IS_ENABLED, &desc->flags);
3304 * If the consumer has not set up a label (such as when the
3305 * IRQ is referenced from .to_irq()) we set up a label here
3306 * so it is clear this is used as an interrupt.
3309 desc_set_label(desc, "interrupt");
3313 EXPORT_SYMBOL_GPL(gpiochip_lock_as_irq);
3316 * gpiochip_unlock_as_irq() - unlock a GPIO used as IRQ
3317 * @gc: the chip the GPIO to lock belongs to
3318 * @offset: the offset of the GPIO to lock as IRQ
3320 * This is used directly by GPIO drivers that want to indicate
3321 * that a certain GPIO is no longer used exclusively for IRQ.
3323 void gpiochip_unlock_as_irq(struct gpio_chip *gc, unsigned int offset)
3325 struct gpio_desc *desc;
3327 desc = gpiochip_get_desc(gc, offset);
3331 clear_bit(FLAG_USED_AS_IRQ, &desc->flags);
3332 clear_bit(FLAG_IRQ_IS_ENABLED, &desc->flags);
3334 /* If we only had this marking, erase it */
3335 if (desc->label && !strcmp(desc->label, "interrupt"))
3336 desc_set_label(desc, NULL);
3338 EXPORT_SYMBOL_GPL(gpiochip_unlock_as_irq);
3340 void gpiochip_disable_irq(struct gpio_chip *gc, unsigned int offset)
3342 struct gpio_desc *desc = gpiochip_get_desc(gc, offset);
3344 if (!IS_ERR(desc) &&
3345 !WARN_ON(!test_bit(FLAG_USED_AS_IRQ, &desc->flags)))
3346 clear_bit(FLAG_IRQ_IS_ENABLED, &desc->flags);
3348 EXPORT_SYMBOL_GPL(gpiochip_disable_irq);
3350 void gpiochip_enable_irq(struct gpio_chip *gc, unsigned int offset)
3352 struct gpio_desc *desc = gpiochip_get_desc(gc, offset);
3354 if (!IS_ERR(desc) &&
3355 !WARN_ON(!test_bit(FLAG_USED_AS_IRQ, &desc->flags))) {
3357 * We must not be output when using IRQ UNLESS we are
3360 WARN_ON(test_bit(FLAG_IS_OUT, &desc->flags) &&
3361 !test_bit(FLAG_OPEN_DRAIN, &desc->flags));
3362 set_bit(FLAG_IRQ_IS_ENABLED, &desc->flags);
3365 EXPORT_SYMBOL_GPL(gpiochip_enable_irq);
3367 bool gpiochip_line_is_irq(struct gpio_chip *gc, unsigned int offset)
3369 if (offset >= gc->ngpio)
3372 return test_bit(FLAG_USED_AS_IRQ, &gc->gpiodev->descs[offset].flags);
3374 EXPORT_SYMBOL_GPL(gpiochip_line_is_irq);
3376 int gpiochip_reqres_irq(struct gpio_chip *gc, unsigned int offset)
3380 if (!try_module_get(gc->gpiodev->owner))
3383 ret = gpiochip_lock_as_irq(gc, offset);
3385 chip_err(gc, "unable to lock HW IRQ %u for IRQ\n", offset);
3386 module_put(gc->gpiodev->owner);
3391 EXPORT_SYMBOL_GPL(gpiochip_reqres_irq);
3393 void gpiochip_relres_irq(struct gpio_chip *gc, unsigned int offset)
3395 gpiochip_unlock_as_irq(gc, offset);
3396 module_put(gc->gpiodev->owner);
3398 EXPORT_SYMBOL_GPL(gpiochip_relres_irq);
3400 bool gpiochip_line_is_open_drain(struct gpio_chip *gc, unsigned int offset)
3402 if (offset >= gc->ngpio)
3405 return test_bit(FLAG_OPEN_DRAIN, &gc->gpiodev->descs[offset].flags);
3407 EXPORT_SYMBOL_GPL(gpiochip_line_is_open_drain);
3409 bool gpiochip_line_is_open_source(struct gpio_chip *gc, unsigned int offset)
3411 if (offset >= gc->ngpio)
3414 return test_bit(FLAG_OPEN_SOURCE, &gc->gpiodev->descs[offset].flags);
3416 EXPORT_SYMBOL_GPL(gpiochip_line_is_open_source);
3418 bool gpiochip_line_is_persistent(struct gpio_chip *gc, unsigned int offset)
3420 if (offset >= gc->ngpio)
3423 return !test_bit(FLAG_TRANSITORY, &gc->gpiodev->descs[offset].flags);
3425 EXPORT_SYMBOL_GPL(gpiochip_line_is_persistent);
3428 * gpiod_get_raw_value_cansleep() - return a gpio's raw value
3429 * @desc: gpio whose value will be returned
3431 * Return the GPIO's raw value, i.e. the value of the physical line disregarding
3432 * its ACTIVE_LOW status, or negative errno on failure.
3434 * This function is to be called from contexts that can sleep.
3436 int gpiod_get_raw_value_cansleep(const struct gpio_desc *desc)
3438 might_sleep_if(extra_checks);
3439 VALIDATE_DESC(desc);
3440 return gpiod_get_raw_value_commit(desc);
3442 EXPORT_SYMBOL_GPL(gpiod_get_raw_value_cansleep);
3445 * gpiod_get_value_cansleep() - return a gpio's value
3446 * @desc: gpio whose value will be returned
3448 * Return the GPIO's logical value, i.e. taking the ACTIVE_LOW status into
3449 * account, or negative errno on failure.
3451 * This function is to be called from contexts that can sleep.
3453 int gpiod_get_value_cansleep(const struct gpio_desc *desc)
3457 might_sleep_if(extra_checks);
3458 VALIDATE_DESC(desc);
3459 value = gpiod_get_raw_value_commit(desc);
3463 if (test_bit(FLAG_ACTIVE_LOW, &desc->flags))
3468 EXPORT_SYMBOL_GPL(gpiod_get_value_cansleep);
3471 * gpiod_get_raw_array_value_cansleep() - read raw values from an array of GPIOs
3472 * @array_size: number of elements in the descriptor array / value bitmap
3473 * @desc_array: array of GPIO descriptors whose values will be read
3474 * @array_info: information on applicability of fast bitmap processing path
3475 * @value_bitmap: bitmap to store the read values
3477 * Read the raw values of the GPIOs, i.e. the values of the physical lines
3478 * without regard for their ACTIVE_LOW status. Return 0 in case of success,
3479 * else an error code.
3481 * This function is to be called from contexts that can sleep.
3483 int gpiod_get_raw_array_value_cansleep(unsigned int array_size,
3484 struct gpio_desc **desc_array,
3485 struct gpio_array *array_info,
3486 unsigned long *value_bitmap)
3488 might_sleep_if(extra_checks);
3491 return gpiod_get_array_value_complex(true, true, array_size,
3492 desc_array, array_info,
3495 EXPORT_SYMBOL_GPL(gpiod_get_raw_array_value_cansleep);
3498 * gpiod_get_array_value_cansleep() - read values from an array of GPIOs
3499 * @array_size: number of elements in the descriptor array / value bitmap
3500 * @desc_array: array of GPIO descriptors whose values will be read
3501 * @array_info: information on applicability of fast bitmap processing path
3502 * @value_bitmap: bitmap to store the read values
3504 * Read the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status
3505 * into account. Return 0 in case of success, else an error code.
3507 * This function is to be called from contexts that can sleep.
3509 int gpiod_get_array_value_cansleep(unsigned int array_size,
3510 struct gpio_desc **desc_array,
3511 struct gpio_array *array_info,
3512 unsigned long *value_bitmap)
3514 might_sleep_if(extra_checks);
3517 return gpiod_get_array_value_complex(false, true, array_size,
3518 desc_array, array_info,
3521 EXPORT_SYMBOL_GPL(gpiod_get_array_value_cansleep);
3524 * gpiod_set_raw_value_cansleep() - assign a gpio's raw value
3525 * @desc: gpio whose value will be assigned
3526 * @value: value to assign
3528 * Set the raw value of the GPIO, i.e. the value of its physical line without
3529 * regard for its ACTIVE_LOW status.
3531 * This function is to be called from contexts that can sleep.
3533 void gpiod_set_raw_value_cansleep(struct gpio_desc *desc, int value)
3535 might_sleep_if(extra_checks);
3536 VALIDATE_DESC_VOID(desc);
3537 gpiod_set_raw_value_commit(desc, value);
3539 EXPORT_SYMBOL_GPL(gpiod_set_raw_value_cansleep);
3542 * gpiod_set_value_cansleep() - assign a gpio's value
3543 * @desc: gpio whose value will be assigned
3544 * @value: value to assign
3546 * Set the logical value of the GPIO, i.e. taking its ACTIVE_LOW status into
3549 * This function is to be called from contexts that can sleep.
3551 void gpiod_set_value_cansleep(struct gpio_desc *desc, int value)
3553 might_sleep_if(extra_checks);
3554 VALIDATE_DESC_VOID(desc);
3555 gpiod_set_value_nocheck(desc, value);
3557 EXPORT_SYMBOL_GPL(gpiod_set_value_cansleep);
3560 * gpiod_set_raw_array_value_cansleep() - assign values to an array of GPIOs
3561 * @array_size: number of elements in the descriptor array / value bitmap
3562 * @desc_array: array of GPIO descriptors whose values will be assigned
3563 * @array_info: information on applicability of fast bitmap processing path
3564 * @value_bitmap: bitmap of values to assign
3566 * Set the raw values of the GPIOs, i.e. the values of the physical lines
3567 * without regard for their ACTIVE_LOW status.
3569 * This function is to be called from contexts that can sleep.
3571 int gpiod_set_raw_array_value_cansleep(unsigned int array_size,
3572 struct gpio_desc **desc_array,
3573 struct gpio_array *array_info,
3574 unsigned long *value_bitmap)
3576 might_sleep_if(extra_checks);
3579 return gpiod_set_array_value_complex(true, true, array_size, desc_array,
3580 array_info, value_bitmap);
3582 EXPORT_SYMBOL_GPL(gpiod_set_raw_array_value_cansleep);
3585 * gpiod_add_lookup_tables() - register GPIO device consumers
3586 * @tables: list of tables of consumers to register
3587 * @n: number of tables in the list
3589 void gpiod_add_lookup_tables(struct gpiod_lookup_table **tables, size_t n)
3593 mutex_lock(&gpio_lookup_lock);
3595 for (i = 0; i < n; i++)
3596 list_add_tail(&tables[i]->list, &gpio_lookup_list);
3598 mutex_unlock(&gpio_lookup_lock);
3602 * gpiod_set_array_value_cansleep() - assign values to an array of GPIOs
3603 * @array_size: number of elements in the descriptor array / value bitmap
3604 * @desc_array: array of GPIO descriptors whose values will be assigned
3605 * @array_info: information on applicability of fast bitmap processing path
3606 * @value_bitmap: bitmap of values to assign
3608 * Set the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status
3611 * This function is to be called from contexts that can sleep.
3613 int gpiod_set_array_value_cansleep(unsigned int array_size,
3614 struct gpio_desc **desc_array,
3615 struct gpio_array *array_info,
3616 unsigned long *value_bitmap)
3618 might_sleep_if(extra_checks);
3621 return gpiod_set_array_value_complex(false, true, array_size,
3622 desc_array, array_info,
3625 EXPORT_SYMBOL_GPL(gpiod_set_array_value_cansleep);
3628 * gpiod_add_lookup_table() - register GPIO device consumers
3629 * @table: table of consumers to register
3631 void gpiod_add_lookup_table(struct gpiod_lookup_table *table)
3633 gpiod_add_lookup_tables(&table, 1);
3635 EXPORT_SYMBOL_GPL(gpiod_add_lookup_table);
3638 * gpiod_remove_lookup_table() - unregister GPIO device consumers
3639 * @table: table of consumers to unregister
3641 void gpiod_remove_lookup_table(struct gpiod_lookup_table *table)
3643 /* Nothing to remove */
3647 mutex_lock(&gpio_lookup_lock);
3649 list_del(&table->list);
3651 mutex_unlock(&gpio_lookup_lock);
3653 EXPORT_SYMBOL_GPL(gpiod_remove_lookup_table);
3656 * gpiod_add_hogs() - register a set of GPIO hogs from machine code
3657 * @hogs: table of gpio hog entries with a zeroed sentinel at the end
3659 void gpiod_add_hogs(struct gpiod_hog *hogs)
3661 struct gpio_chip *gc;
3662 struct gpiod_hog *hog;
3664 mutex_lock(&gpio_machine_hogs_mutex);
3666 for (hog = &hogs[0]; hog->chip_label; hog++) {
3667 list_add_tail(&hog->list, &gpio_machine_hogs);
3670 * The chip may have been registered earlier, so check if it
3671 * exists and, if so, try to hog the line now.
3673 gc = find_chip_by_name(hog->chip_label);
3675 gpiochip_machine_hog(gc, hog);
3678 mutex_unlock(&gpio_machine_hogs_mutex);
3680 EXPORT_SYMBOL_GPL(gpiod_add_hogs);
3682 void gpiod_remove_hogs(struct gpiod_hog *hogs)
3684 struct gpiod_hog *hog;
3686 mutex_lock(&gpio_machine_hogs_mutex);
3687 for (hog = &hogs[0]; hog->chip_label; hog++)
3688 list_del(&hog->list);
3689 mutex_unlock(&gpio_machine_hogs_mutex);
3691 EXPORT_SYMBOL_GPL(gpiod_remove_hogs);
3693 static struct gpiod_lookup_table *gpiod_find_lookup_table(struct device *dev)
3695 const char *dev_id = dev ? dev_name(dev) : NULL;
3696 struct gpiod_lookup_table *table;
3698 mutex_lock(&gpio_lookup_lock);
3700 list_for_each_entry(table, &gpio_lookup_list, list) {
3701 if (table->dev_id && dev_id) {
3703 * Valid strings on both ends, must be identical to have
3706 if (!strcmp(table->dev_id, dev_id))
3710 * One of the pointers is NULL, so both must be to have
3713 if (dev_id == table->dev_id)
3720 mutex_unlock(&gpio_lookup_lock);
3724 static struct gpio_desc *gpiod_find(struct device *dev, const char *con_id,
3725 unsigned int idx, unsigned long *flags)
3727 struct gpio_desc *desc = ERR_PTR(-ENOENT);
3728 struct gpiod_lookup_table *table;
3729 struct gpiod_lookup *p;
3731 table = gpiod_find_lookup_table(dev);
3735 for (p = &table->table[0]; p->key; p++) {
3736 struct gpio_chip *gc;
3738 /* idx must always match exactly */
3742 /* If the lookup entry has a con_id, require exact match */
3743 if (p->con_id && (!con_id || strcmp(p->con_id, con_id)))
3746 if (p->chip_hwnum == U16_MAX) {
3747 desc = gpio_name_to_desc(p->key);
3753 dev_warn(dev, "cannot find GPIO line %s, deferring\n",
3755 return ERR_PTR(-EPROBE_DEFER);
3758 gc = find_chip_by_name(p->key);
3762 * As the lookup table indicates a chip with
3763 * p->key should exist, assume it may
3764 * still appear later and let the interested
3765 * consumer be probed again or let the Deferred
3766 * Probe infrastructure handle the error.
3768 dev_warn(dev, "cannot find GPIO chip %s, deferring\n",
3770 return ERR_PTR(-EPROBE_DEFER);
3773 if (gc->ngpio <= p->chip_hwnum) {
3775 "requested GPIO %u (%u) is out of range [0..%u] for chip %s\n",
3776 idx, p->chip_hwnum, gc->ngpio - 1,
3778 return ERR_PTR(-EINVAL);
3781 desc = gpiochip_get_desc(gc, p->chip_hwnum);
3790 static int platform_gpio_count(struct device *dev, const char *con_id)
3792 struct gpiod_lookup_table *table;
3793 struct gpiod_lookup *p;
3794 unsigned int count = 0;
3796 table = gpiod_find_lookup_table(dev);
3800 for (p = &table->table[0]; p->key; p++) {
3801 if ((con_id && p->con_id && !strcmp(con_id, p->con_id)) ||
3802 (!con_id && !p->con_id))
3812 * fwnode_get_named_gpiod - obtain a GPIO from firmware node
3813 * @fwnode: handle of the firmware node
3814 * @propname: name of the firmware property representing the GPIO
3815 * @index: index of the GPIO to obtain for the consumer
3816 * @dflags: GPIO initialization flags
3817 * @label: label to attach to the requested GPIO
3819 * This function can be used for drivers that get their configuration
3820 * from opaque firmware.
3822 * The function properly finds the corresponding GPIO using whatever is the
3823 * underlying firmware interface and then makes sure that the GPIO
3824 * descriptor is requested before it is returned to the caller.
3827 * On successful request the GPIO pin is configured in accordance with
3830 * In case of error an ERR_PTR() is returned.
3832 static struct gpio_desc *fwnode_get_named_gpiod(struct fwnode_handle *fwnode,
3833 const char *propname, int index,
3834 enum gpiod_flags dflags,
3837 unsigned long lflags = GPIO_LOOKUP_FLAGS_DEFAULT;
3838 struct gpio_desc *desc = ERR_PTR(-ENODEV);
3841 if (is_of_node(fwnode)) {
3842 desc = gpiod_get_from_of_node(to_of_node(fwnode),
3847 } else if (is_acpi_node(fwnode)) {
3848 struct acpi_gpio_info info;
3850 desc = acpi_node_get_gpiod(fwnode, propname, index, &info);
3854 acpi_gpio_update_gpiod_flags(&dflags, &info);
3855 acpi_gpio_update_gpiod_lookup_flags(&lflags, &info);
3857 return ERR_PTR(-EINVAL);
3860 /* Currently only ACPI takes this path */
3861 ret = gpiod_request(desc, label);
3863 return ERR_PTR(ret);
3865 ret = gpiod_configure_flags(desc, propname, lflags, dflags);
3868 return ERR_PTR(ret);
3871 blocking_notifier_call_chain(&desc->gdev->notifier,
3872 GPIOLINE_CHANGED_REQUESTED, desc);
3878 * fwnode_gpiod_get_index - obtain a GPIO from firmware node
3879 * @fwnode: handle of the firmware node
3880 * @con_id: function within the GPIO consumer
3881 * @index: index of the GPIO to obtain for the consumer
3882 * @flags: GPIO initialization flags
3883 * @label: label to attach to the requested GPIO
3885 * This function can be used for drivers that get their configuration
3886 * from opaque firmware.
3888 * The function properly finds the corresponding GPIO using whatever is the
3889 * underlying firmware interface and then makes sure that the GPIO
3890 * descriptor is requested before it is returned to the caller.
3893 * On successful request the GPIO pin is configured in accordance with
3896 * In case of error an ERR_PTR() is returned.
3898 struct gpio_desc *fwnode_gpiod_get_index(struct fwnode_handle *fwnode,
3899 const char *con_id, int index,
3900 enum gpiod_flags flags,
3903 struct gpio_desc *desc;
3904 char prop_name[32]; /* 32 is max size of property name */
3907 for (i = 0; i < ARRAY_SIZE(gpio_suffixes); i++) {
3909 snprintf(prop_name, sizeof(prop_name), "%s-%s",
3910 con_id, gpio_suffixes[i]);
3912 snprintf(prop_name, sizeof(prop_name), "%s",
3915 desc = fwnode_get_named_gpiod(fwnode, prop_name, index, flags,
3917 if (!gpiod_not_found(desc))
3923 EXPORT_SYMBOL_GPL(fwnode_gpiod_get_index);
3926 * gpiod_count - return the number of GPIOs associated with a device / function
3927 * or -ENOENT if no GPIO has been assigned to the requested function
3928 * @dev: GPIO consumer, can be NULL for system-global GPIOs
3929 * @con_id: function within the GPIO consumer
3931 int gpiod_count(struct device *dev, const char *con_id)
3933 const struct fwnode_handle *fwnode = dev ? dev_fwnode(dev) : NULL;
3934 int count = -ENOENT;
3936 if (is_of_node(fwnode))
3937 count = of_gpio_get_count(dev, con_id);
3938 else if (is_acpi_node(fwnode))
3939 count = acpi_gpio_count(dev, con_id);
3942 count = platform_gpio_count(dev, con_id);
3946 EXPORT_SYMBOL_GPL(gpiod_count);
3949 * gpiod_get - obtain a GPIO for a given GPIO function
3950 * @dev: GPIO consumer, can be NULL for system-global GPIOs
3951 * @con_id: function within the GPIO consumer
3952 * @flags: optional GPIO initialization flags
3954 * Return the GPIO descriptor corresponding to the function con_id of device
3955 * dev, -ENOENT if no GPIO has been assigned to the requested function, or
3956 * another IS_ERR() code if an error occurred while trying to acquire the GPIO.
3958 struct gpio_desc *__must_check gpiod_get(struct device *dev, const char *con_id,
3959 enum gpiod_flags flags)
3961 return gpiod_get_index(dev, con_id, 0, flags);
3963 EXPORT_SYMBOL_GPL(gpiod_get);
3966 * gpiod_get_optional - obtain an optional GPIO for a given GPIO function
3967 * @dev: GPIO consumer, can be NULL for system-global GPIOs
3968 * @con_id: function within the GPIO consumer
3969 * @flags: optional GPIO initialization flags
3971 * This is equivalent to gpiod_get(), except that when no GPIO was assigned to
3972 * the requested function it will return NULL. This is convenient for drivers
3973 * that need to handle optional GPIOs.
3975 struct gpio_desc *__must_check gpiod_get_optional(struct device *dev,
3977 enum gpiod_flags flags)
3979 return gpiod_get_index_optional(dev, con_id, 0, flags);
3981 EXPORT_SYMBOL_GPL(gpiod_get_optional);
3985 * gpiod_configure_flags - helper function to configure a given GPIO
3986 * @desc: gpio whose value will be assigned
3987 * @con_id: function within the GPIO consumer
3988 * @lflags: bitmask of gpio_lookup_flags GPIO_* values - returned from
3989 * of_find_gpio() or of_get_gpio_hog()
3990 * @dflags: gpiod_flags - optional GPIO initialization flags
3992 * Return 0 on success, -ENOENT if no GPIO has been assigned to the
3993 * requested function and/or index, or another IS_ERR() code if an error
3994 * occurred while trying to acquire the GPIO.
3996 int gpiod_configure_flags(struct gpio_desc *desc, const char *con_id,
3997 unsigned long lflags, enum gpiod_flags dflags)
4001 if (lflags & GPIO_ACTIVE_LOW)
4002 set_bit(FLAG_ACTIVE_LOW, &desc->flags);
4004 if (lflags & GPIO_OPEN_DRAIN)
4005 set_bit(FLAG_OPEN_DRAIN, &desc->flags);
4006 else if (dflags & GPIOD_FLAGS_BIT_OPEN_DRAIN) {
4008 * This enforces open drain mode from the consumer side.
4009 * This is necessary for some busses like I2C, but the lookup
4010 * should *REALLY* have specified them as open drain in the
4011 * first place, so print a little warning here.
4013 set_bit(FLAG_OPEN_DRAIN, &desc->flags);
4015 "enforced open drain please flag it properly in DT/ACPI DSDT/board file\n");
4018 if (lflags & GPIO_OPEN_SOURCE)
4019 set_bit(FLAG_OPEN_SOURCE, &desc->flags);
4021 if (((lflags & GPIO_PULL_UP) && (lflags & GPIO_PULL_DOWN)) ||
4022 ((lflags & GPIO_PULL_UP) && (lflags & GPIO_PULL_DISABLE)) ||
4023 ((lflags & GPIO_PULL_DOWN) && (lflags & GPIO_PULL_DISABLE))) {
4025 "multiple pull-up, pull-down or pull-disable enabled, invalid configuration\n");
4029 if (lflags & GPIO_PULL_UP)
4030 set_bit(FLAG_PULL_UP, &desc->flags);
4031 else if (lflags & GPIO_PULL_DOWN)
4032 set_bit(FLAG_PULL_DOWN, &desc->flags);
4033 else if (lflags & GPIO_PULL_DISABLE)
4034 set_bit(FLAG_BIAS_DISABLE, &desc->flags);
4036 ret = gpiod_set_transitory(desc, (lflags & GPIO_TRANSITORY));
4040 /* No particular flag request, return here... */
4041 if (!(dflags & GPIOD_FLAGS_BIT_DIR_SET)) {
4042 gpiod_dbg(desc, "no flags found for %s\n", con_id);
4047 if (dflags & GPIOD_FLAGS_BIT_DIR_OUT)
4048 ret = gpiod_direction_output(desc,
4049 !!(dflags & GPIOD_FLAGS_BIT_DIR_VAL));
4051 ret = gpiod_direction_input(desc);
4057 * gpiod_get_index - obtain a GPIO from a multi-index GPIO function
4058 * @dev: GPIO consumer, can be NULL for system-global GPIOs
4059 * @con_id: function within the GPIO consumer
4060 * @idx: index of the GPIO to obtain in the consumer
4061 * @flags: optional GPIO initialization flags
4063 * This variant of gpiod_get() allows to access GPIOs other than the first
4064 * defined one for functions that define several GPIOs.
4066 * Return a valid GPIO descriptor, -ENOENT if no GPIO has been assigned to the
4067 * requested function and/or index, or another IS_ERR() code if an error
4068 * occurred while trying to acquire the GPIO.
4070 struct gpio_desc *__must_check gpiod_get_index(struct device *dev,
4073 enum gpiod_flags flags)
4075 unsigned long lookupflags = GPIO_LOOKUP_FLAGS_DEFAULT;
4076 struct gpio_desc *desc = NULL;
4078 /* Maybe we have a device name, maybe not */
4079 const char *devname = dev ? dev_name(dev) : "?";
4080 const struct fwnode_handle *fwnode = dev ? dev_fwnode(dev) : NULL;
4082 dev_dbg(dev, "GPIO lookup for consumer %s\n", con_id);
4084 /* Using device tree? */
4085 if (is_of_node(fwnode)) {
4086 dev_dbg(dev, "using device tree for GPIO lookup\n");
4087 desc = of_find_gpio(dev, con_id, idx, &lookupflags);
4088 } else if (is_acpi_node(fwnode)) {
4089 dev_dbg(dev, "using ACPI for GPIO lookup\n");
4090 desc = acpi_find_gpio(dev, con_id, idx, &flags, &lookupflags);
4094 * Either we are not using DT or ACPI, or their lookup did not return
4095 * a result. In that case, use platform lookup as a fallback.
4097 if (!desc || gpiod_not_found(desc)) {
4098 dev_dbg(dev, "using lookup tables for GPIO lookup\n");
4099 desc = gpiod_find(dev, con_id, idx, &lookupflags);
4103 dev_dbg(dev, "No GPIO consumer %s found\n", con_id);
4108 * If a connection label was passed use that, else attempt to use
4109 * the device name as label
4111 ret = gpiod_request(desc, con_id ?: devname);
4113 if (!(ret == -EBUSY && flags & GPIOD_FLAGS_BIT_NONEXCLUSIVE))
4114 return ERR_PTR(ret);
4117 * This happens when there are several consumers for
4118 * the same GPIO line: we just return here without
4119 * further initialization. It is a bit of a hack.
4120 * This is necessary to support fixed regulators.
4122 * FIXME: Make this more sane and safe.
4124 dev_info(dev, "nonexclusive access to GPIO for %s\n", con_id ?: devname);
4128 ret = gpiod_configure_flags(desc, con_id, lookupflags, flags);
4130 dev_dbg(dev, "setup of GPIO %s failed\n", con_id);
4132 return ERR_PTR(ret);
4135 blocking_notifier_call_chain(&desc->gdev->notifier,
4136 GPIOLINE_CHANGED_REQUESTED, desc);
4140 EXPORT_SYMBOL_GPL(gpiod_get_index);
4143 * gpiod_get_index_optional - obtain an optional GPIO from a multi-index GPIO
4145 * @dev: GPIO consumer, can be NULL for system-global GPIOs
4146 * @con_id: function within the GPIO consumer
4147 * @index: index of the GPIO to obtain in the consumer
4148 * @flags: optional GPIO initialization flags
4150 * This is equivalent to gpiod_get_index(), except that when no GPIO with the
4151 * specified index was assigned to the requested function it will return NULL.
4152 * This is convenient for drivers that need to handle optional GPIOs.
4154 struct gpio_desc *__must_check gpiod_get_index_optional(struct device *dev,
4157 enum gpiod_flags flags)
4159 struct gpio_desc *desc;
4161 desc = gpiod_get_index(dev, con_id, index, flags);
4162 if (gpiod_not_found(desc))
4167 EXPORT_SYMBOL_GPL(gpiod_get_index_optional);
4170 * gpiod_hog - Hog the specified GPIO desc given the provided flags
4171 * @desc: gpio whose value will be assigned
4172 * @name: gpio line name
4173 * @lflags: bitmask of gpio_lookup_flags GPIO_* values - returned from
4174 * of_find_gpio() or of_get_gpio_hog()
4175 * @dflags: gpiod_flags - optional GPIO initialization flags
4177 int gpiod_hog(struct gpio_desc *desc, const char *name,
4178 unsigned long lflags, enum gpiod_flags dflags)
4180 struct gpio_chip *gc;
4181 struct gpio_desc *local_desc;
4185 gc = gpiod_to_chip(desc);
4186 hwnum = gpio_chip_hwgpio(desc);
4188 local_desc = gpiochip_request_own_desc(gc, hwnum, name,
4190 if (IS_ERR(local_desc)) {
4191 ret = PTR_ERR(local_desc);
4192 pr_err("requesting hog GPIO %s (chip %s, offset %d) failed, %d\n",
4193 name, gc->label, hwnum, ret);
4197 /* Mark GPIO as hogged so it can be identified and removed later */
4198 set_bit(FLAG_IS_HOGGED, &desc->flags);
4200 gpiod_info(desc, "hogged as %s%s\n",
4201 (dflags & GPIOD_FLAGS_BIT_DIR_OUT) ? "output" : "input",
4202 (dflags & GPIOD_FLAGS_BIT_DIR_OUT) ?
4203 (dflags & GPIOD_FLAGS_BIT_DIR_VAL) ? "/high" : "/low" : "");
4209 * gpiochip_free_hogs - Scan gpio-controller chip and release GPIO hog
4210 * @gc: gpio chip to act on
4212 static void gpiochip_free_hogs(struct gpio_chip *gc)
4214 struct gpio_desc *desc;
4216 for_each_gpio_desc_with_flag(gc, desc, FLAG_IS_HOGGED)
4217 gpiochip_free_own_desc(desc);
4221 * gpiod_get_array - obtain multiple GPIOs from a multi-index GPIO function
4222 * @dev: GPIO consumer, can be NULL for system-global GPIOs
4223 * @con_id: function within the GPIO consumer
4224 * @flags: optional GPIO initialization flags
4226 * This function acquires all the GPIOs defined under a given function.
4228 * Return a struct gpio_descs containing an array of descriptors, -ENOENT if
4229 * no GPIO has been assigned to the requested function, or another IS_ERR()
4230 * code if an error occurred while trying to acquire the GPIOs.
4232 struct gpio_descs *__must_check gpiod_get_array(struct device *dev,
4234 enum gpiod_flags flags)
4236 struct gpio_desc *desc;
4237 struct gpio_descs *descs;
4238 struct gpio_array *array_info = NULL;
4239 struct gpio_chip *gc;
4240 int count, bitmap_size;
4242 count = gpiod_count(dev, con_id);
4244 return ERR_PTR(count);
4246 descs = kzalloc(struct_size(descs, desc, count), GFP_KERNEL);
4248 return ERR_PTR(-ENOMEM);
4250 for (descs->ndescs = 0; descs->ndescs < count; ) {
4251 desc = gpiod_get_index(dev, con_id, descs->ndescs, flags);
4253 gpiod_put_array(descs);
4254 return ERR_CAST(desc);
4257 descs->desc[descs->ndescs] = desc;
4259 gc = gpiod_to_chip(desc);
4261 * If pin hardware number of array member 0 is also 0, select
4262 * its chip as a candidate for fast bitmap processing path.
4264 if (descs->ndescs == 0 && gpio_chip_hwgpio(desc) == 0) {
4265 struct gpio_descs *array;
4267 bitmap_size = BITS_TO_LONGS(gc->ngpio > count ?
4270 array = kzalloc(struct_size(descs, desc, count) +
4271 struct_size(array_info, invert_mask,
4272 3 * bitmap_size), GFP_KERNEL);
4274 gpiod_put_array(descs);
4275 return ERR_PTR(-ENOMEM);
4278 memcpy(array, descs,
4279 struct_size(descs, desc, descs->ndescs + 1));
4283 array_info = (void *)(descs->desc + count);
4284 array_info->get_mask = array_info->invert_mask +
4286 array_info->set_mask = array_info->get_mask +
4289 array_info->desc = descs->desc;
4290 array_info->size = count;
4291 array_info->chip = gc;
4292 bitmap_set(array_info->get_mask, descs->ndescs,
4293 count - descs->ndescs);
4294 bitmap_set(array_info->set_mask, descs->ndescs,
4295 count - descs->ndescs);
4296 descs->info = array_info;
4298 /* Unmark array members which don't belong to the 'fast' chip */
4299 if (array_info && array_info->chip != gc) {
4300 __clear_bit(descs->ndescs, array_info->get_mask);
4301 __clear_bit(descs->ndescs, array_info->set_mask);
4304 * Detect array members which belong to the 'fast' chip
4305 * but their pins are not in hardware order.
4307 else if (array_info &&
4308 gpio_chip_hwgpio(desc) != descs->ndescs) {
4310 * Don't use fast path if all array members processed so
4311 * far belong to the same chip as this one but its pin
4312 * hardware number is different from its array index.
4314 if (bitmap_full(array_info->get_mask, descs->ndescs)) {
4317 __clear_bit(descs->ndescs,
4318 array_info->get_mask);
4319 __clear_bit(descs->ndescs,
4320 array_info->set_mask);
4322 } else if (array_info) {
4323 /* Exclude open drain or open source from fast output */
4324 if (gpiochip_line_is_open_drain(gc, descs->ndescs) ||
4325 gpiochip_line_is_open_source(gc, descs->ndescs))
4326 __clear_bit(descs->ndescs,
4327 array_info->set_mask);
4328 /* Identify 'fast' pins which require invertion */
4329 if (gpiod_is_active_low(desc))
4330 __set_bit(descs->ndescs,
4331 array_info->invert_mask);
4338 "GPIO array info: chip=%s, size=%d, get_mask=%lx, set_mask=%lx, invert_mask=%lx\n",
4339 array_info->chip->label, array_info->size,
4340 *array_info->get_mask, *array_info->set_mask,
4341 *array_info->invert_mask);
4344 EXPORT_SYMBOL_GPL(gpiod_get_array);
4347 * gpiod_get_array_optional - obtain multiple GPIOs from a multi-index GPIO
4349 * @dev: GPIO consumer, can be NULL for system-global GPIOs
4350 * @con_id: function within the GPIO consumer
4351 * @flags: optional GPIO initialization flags
4353 * This is equivalent to gpiod_get_array(), except that when no GPIO was
4354 * assigned to the requested function it will return NULL.
4356 struct gpio_descs *__must_check gpiod_get_array_optional(struct device *dev,
4358 enum gpiod_flags flags)
4360 struct gpio_descs *descs;
4362 descs = gpiod_get_array(dev, con_id, flags);
4363 if (gpiod_not_found(descs))
4368 EXPORT_SYMBOL_GPL(gpiod_get_array_optional);
4371 * gpiod_put - dispose of a GPIO descriptor
4372 * @desc: GPIO descriptor to dispose of
4374 * No descriptor can be used after gpiod_put() has been called on it.
4376 void gpiod_put(struct gpio_desc *desc)
4381 EXPORT_SYMBOL_GPL(gpiod_put);
4384 * gpiod_put_array - dispose of multiple GPIO descriptors
4385 * @descs: struct gpio_descs containing an array of descriptors
4387 void gpiod_put_array(struct gpio_descs *descs)
4391 for (i = 0; i < descs->ndescs; i++)
4392 gpiod_put(descs->desc[i]);
4396 EXPORT_SYMBOL_GPL(gpiod_put_array);
4399 static int gpio_bus_match(struct device *dev, struct device_driver *drv)
4401 struct fwnode_handle *fwnode = dev_fwnode(dev);
4404 * Only match if the fwnode doesn't already have a proper struct device
4407 if (fwnode && fwnode->dev != dev)
4412 static int gpio_stub_drv_probe(struct device *dev)
4415 * The DT node of some GPIO chips have a "compatible" property, but
4416 * never have a struct device added and probed by a driver to register
4417 * the GPIO chip with gpiolib. In such cases, fw_devlink=on will cause
4418 * the consumers of the GPIO chip to get probe deferred forever because
4419 * they will be waiting for a device associated with the GPIO chip
4420 * firmware node to get added and bound to a driver.
4422 * To allow these consumers to probe, we associate the struct
4423 * gpio_device of the GPIO chip with the firmware node and then simply
4424 * bind it to this stub driver.
4429 static struct device_driver gpio_stub_drv = {
4430 .name = "gpio_stub_drv",
4431 .bus = &gpio_bus_type,
4432 .probe = gpio_stub_drv_probe,
4435 static int __init gpiolib_dev_init(void)
4439 /* Register GPIO sysfs bus */
4440 ret = bus_register(&gpio_bus_type);
4442 pr_err("gpiolib: could not register GPIO bus type\n");
4446 ret = driver_register(&gpio_stub_drv);
4448 pr_err("gpiolib: could not register GPIO stub driver\n");
4449 bus_unregister(&gpio_bus_type);
4453 ret = alloc_chrdev_region(&gpio_devt, 0, GPIO_DEV_MAX, GPIOCHIP_NAME);
4455 pr_err("gpiolib: failed to allocate char dev region\n");
4456 driver_unregister(&gpio_stub_drv);
4457 bus_unregister(&gpio_bus_type);
4461 gpiolib_initialized = true;
4462 gpiochip_setup_devs();
4464 #if IS_ENABLED(CONFIG_OF_DYNAMIC) && IS_ENABLED(CONFIG_OF_GPIO)
4465 WARN_ON(of_reconfig_notifier_register(&gpio_of_notifier));
4466 #endif /* CONFIG_OF_DYNAMIC && CONFIG_OF_GPIO */
4470 core_initcall(gpiolib_dev_init);
4472 #ifdef CONFIG_DEBUG_FS
4474 static void gpiolib_dbg_show(struct seq_file *s, struct gpio_device *gdev)
4476 struct gpio_chip *gc = gdev->chip;
4477 struct gpio_desc *desc;
4478 unsigned gpio = gdev->base;
4484 for_each_gpio_desc(gc, desc) {
4485 if (test_bit(FLAG_REQUESTED, &desc->flags)) {
4486 gpiod_get_direction(desc);
4487 is_out = test_bit(FLAG_IS_OUT, &desc->flags);
4488 value = gpio_chip_get_value(gc, desc);
4489 is_irq = test_bit(FLAG_USED_AS_IRQ, &desc->flags);
4490 active_low = test_bit(FLAG_ACTIVE_LOW, &desc->flags);
4491 seq_printf(s, " gpio-%-3d (%-20.20s|%-20.20s) %s %s %s%s\n",
4492 gpio, desc->name ?: "", desc->label,
4493 is_out ? "out" : "in ",
4494 value >= 0 ? (value ? "hi" : "lo") : "? ",
4495 is_irq ? "IRQ " : "",
4496 active_low ? "ACTIVE LOW" : "");
4497 } else if (desc->name) {
4498 seq_printf(s, " gpio-%-3d (%-20.20s)\n", gpio, desc->name);
4505 static void *gpiolib_seq_start(struct seq_file *s, loff_t *pos)
4507 unsigned long flags;
4508 struct gpio_device *gdev = NULL;
4509 loff_t index = *pos;
4513 spin_lock_irqsave(&gpio_lock, flags);
4514 list_for_each_entry(gdev, &gpio_devices, list)
4516 spin_unlock_irqrestore(&gpio_lock, flags);
4519 spin_unlock_irqrestore(&gpio_lock, flags);
4524 static void *gpiolib_seq_next(struct seq_file *s, void *v, loff_t *pos)
4526 unsigned long flags;
4527 struct gpio_device *gdev = v;
4530 spin_lock_irqsave(&gpio_lock, flags);
4531 if (list_is_last(&gdev->list, &gpio_devices))
4534 ret = list_first_entry(&gdev->list, struct gpio_device, list);
4535 spin_unlock_irqrestore(&gpio_lock, flags);
4543 static void gpiolib_seq_stop(struct seq_file *s, void *v)
4547 static int gpiolib_seq_show(struct seq_file *s, void *v)
4549 struct gpio_device *gdev = v;
4550 struct gpio_chip *gc = gdev->chip;
4551 struct device *parent;
4554 seq_printf(s, "%s%s: (dangling chip)", (char *)s->private,
4555 dev_name(&gdev->dev));
4559 seq_printf(s, "%s%s: GPIOs %d-%d", (char *)s->private,
4560 dev_name(&gdev->dev),
4561 gdev->base, gdev->base + gdev->ngpio - 1);
4562 parent = gc->parent;
4564 seq_printf(s, ", parent: %s/%s",
4565 parent->bus ? parent->bus->name : "no-bus",
4568 seq_printf(s, ", %s", gc->label);
4570 seq_printf(s, ", can sleep");
4571 seq_printf(s, ":\n");
4574 gc->dbg_show(s, gc);
4576 gpiolib_dbg_show(s, gdev);
4581 static const struct seq_operations gpiolib_sops = {
4582 .start = gpiolib_seq_start,
4583 .next = gpiolib_seq_next,
4584 .stop = gpiolib_seq_stop,
4585 .show = gpiolib_seq_show,
4587 DEFINE_SEQ_ATTRIBUTE(gpiolib);
4589 static int __init gpiolib_debugfs_init(void)
4591 /* /sys/kernel/debug/gpio */
4592 debugfs_create_file("gpio", 0444, NULL, NULL, &gpiolib_fops);
4595 subsys_initcall(gpiolib_debugfs_init);
4597 #endif /* DEBUG_FS */