1 // SPDX-License-Identifier: GPL-2.0
3 #include <linux/acpi.h>
4 #include <linux/bitmap.h>
5 #include <linux/cleanup.h>
6 #include <linux/compat.h>
7 #include <linux/debugfs.h>
8 #include <linux/device.h>
10 #include <linux/errno.h>
11 #include <linux/file.h>
13 #include <linux/idr.h>
14 #include <linux/interrupt.h>
15 #include <linux/irq.h>
16 #include <linux/kernel.h>
17 #include <linux/list.h>
18 #include <linux/lockdep.h>
19 #include <linux/module.h>
21 #include <linux/pinctrl/consumer.h>
22 #include <linux/seq_file.h>
23 #include <linux/slab.h>
24 #include <linux/spinlock.h>
25 #include <linux/srcu.h>
26 #include <linux/string.h>
28 #include <linux/gpio.h>
29 #include <linux/gpio/driver.h>
30 #include <linux/gpio/machine.h>
32 #include <uapi/linux/gpio.h>
34 #include "gpiolib-acpi.h"
35 #include "gpiolib-cdev.h"
36 #include "gpiolib-of.h"
37 #include "gpiolib-swnode.h"
38 #include "gpiolib-sysfs.h"
41 #define CREATE_TRACE_POINTS
42 #include <trace/events/gpio.h>
44 /* Implementation infrastructure for GPIO interfaces.
46 * The GPIO programming interface allows for inlining speed-critical
47 * get/set operations for common cases, so that access to SOC-integrated
48 * GPIOs can sometimes cost only an instruction or two per bit.
51 /* Device and char device-related information */
52 static DEFINE_IDA(gpio_ida);
53 static dev_t gpio_devt;
54 #define GPIO_DEV_MAX 256 /* 256 GPIO chip devices supported */
56 static int gpio_bus_match(struct device *dev, struct device_driver *drv)
58 struct fwnode_handle *fwnode = dev_fwnode(dev);
61 * Only match if the fwnode doesn't already have a proper struct device
64 if (fwnode && fwnode->dev != dev)
69 static const struct bus_type gpio_bus_type = {
71 .match = gpio_bus_match,
75 * Number of GPIOs to use for the fast path in set array
77 #define FASTPATH_NGPIO CONFIG_GPIOLIB_FASTPATH_LIMIT
79 static DEFINE_MUTEX(gpio_lookup_lock);
80 static LIST_HEAD(gpio_lookup_list);
82 static LIST_HEAD(gpio_devices);
83 /* Protects the GPIO device list against concurrent modifications. */
84 static DEFINE_MUTEX(gpio_devices_lock);
85 /* Ensures coherence during read-only accesses to the list of GPIO devices. */
86 DEFINE_STATIC_SRCU(gpio_devices_srcu);
88 static DEFINE_MUTEX(gpio_machine_hogs_mutex);
89 static LIST_HEAD(gpio_machine_hogs);
91 static void gpiochip_free_hogs(struct gpio_chip *gc);
92 static int gpiochip_add_irqchip(struct gpio_chip *gc,
93 struct lock_class_key *lock_key,
94 struct lock_class_key *request_key);
95 static void gpiochip_irqchip_remove(struct gpio_chip *gc);
96 static int gpiochip_irqchip_init_hw(struct gpio_chip *gc);
97 static int gpiochip_irqchip_init_valid_mask(struct gpio_chip *gc);
98 static void gpiochip_irqchip_free_valid_mask(struct gpio_chip *gc);
100 static bool gpiolib_initialized;
102 const char *gpiod_get_label(struct gpio_desc *desc)
104 struct gpio_desc_label *label;
107 flags = READ_ONCE(desc->flags);
108 if (test_bit(FLAG_USED_AS_IRQ, &flags) &&
109 !test_bit(FLAG_REQUESTED, &flags))
112 if (!test_bit(FLAG_REQUESTED, &flags))
115 label = srcu_dereference_check(desc->label, &desc->gdev->desc_srcu,
116 srcu_read_lock_held(&desc->gdev->desc_srcu));
121 static void desc_free_label(struct rcu_head *rh)
123 kfree(container_of(rh, struct gpio_desc_label, rh));
126 static int desc_set_label(struct gpio_desc *desc, const char *label)
128 struct gpio_desc_label *new = NULL, *old;
131 new = kzalloc(struct_size(new, str, strlen(label) + 1),
136 strcpy(new->str, label);
139 old = rcu_replace_pointer(desc->label, new, 1);
141 call_srcu(&desc->gdev->desc_srcu, &old->rh, desc_free_label);
147 * gpio_to_desc - Convert a GPIO number to its descriptor
148 * @gpio: global GPIO number
151 * The GPIO descriptor associated with the given GPIO, or %NULL if no GPIO
152 * with the given number exists in the system.
154 struct gpio_desc *gpio_to_desc(unsigned gpio)
156 struct gpio_device *gdev;
158 scoped_guard(srcu, &gpio_devices_srcu) {
159 list_for_each_entry_srcu(gdev, &gpio_devices, list,
160 srcu_read_lock_held(&gpio_devices_srcu)) {
161 if (gdev->base <= gpio &&
162 gdev->base + gdev->ngpio > gpio)
163 return &gdev->descs[gpio - gdev->base];
167 if (!gpio_is_valid(gpio))
168 pr_warn("invalid GPIO %d\n", gpio);
172 EXPORT_SYMBOL_GPL(gpio_to_desc);
174 /* This function is deprecated and will be removed soon, don't use. */
175 struct gpio_desc *gpiochip_get_desc(struct gpio_chip *gc,
178 return gpio_device_get_desc(gc->gpiodev, hwnum);
180 EXPORT_SYMBOL_GPL(gpiochip_get_desc);
183 * gpio_device_get_desc() - get the GPIO descriptor corresponding to the given
184 * hardware number for this GPIO device
185 * @gdev: GPIO device to get the descriptor from
186 * @hwnum: hardware number of the GPIO for this chip
189 * A pointer to the GPIO descriptor or %EINVAL if no GPIO exists in the given
190 * chip for the specified hardware number or %ENODEV if the underlying chip
193 * The reference count of struct gpio_device is *NOT* increased like when the
194 * GPIO is being requested for exclusive usage. It's up to the caller to make
195 * sure the GPIO device will stay alive together with the descriptor returned
199 gpio_device_get_desc(struct gpio_device *gdev, unsigned int hwnum)
201 if (hwnum >= gdev->ngpio)
202 return ERR_PTR(-EINVAL);
204 return &gdev->descs[hwnum];
206 EXPORT_SYMBOL_GPL(gpio_device_get_desc);
209 * desc_to_gpio - convert a GPIO descriptor to the integer namespace
210 * @desc: GPIO descriptor
212 * This should disappear in the future but is needed since we still
213 * use GPIO numbers for error messages and sysfs nodes.
216 * The global GPIO number for the GPIO specified by its descriptor.
218 int desc_to_gpio(const struct gpio_desc *desc)
220 return desc->gdev->base + (desc - &desc->gdev->descs[0]);
222 EXPORT_SYMBOL_GPL(desc_to_gpio);
226 * gpiod_to_chip - Return the GPIO chip to which a GPIO descriptor belongs
227 * @desc: descriptor to return the chip of
230 * This function is unsafe and should not be used. Using the chip address
231 * without taking the SRCU read lock may result in dereferencing a dangling
234 struct gpio_chip *gpiod_to_chip(const struct gpio_desc *desc)
239 return gpio_device_get_chip(desc->gdev);
241 EXPORT_SYMBOL_GPL(gpiod_to_chip);
244 * gpiod_to_gpio_device() - Return the GPIO device to which this descriptor
246 * @desc: Descriptor for which to return the GPIO device.
248 * This *DOES NOT* increase the reference count of the GPIO device as it's
249 * expected that the descriptor is requested and the users already holds a
250 * reference to the device.
253 * Address of the GPIO device owning this descriptor.
255 struct gpio_device *gpiod_to_gpio_device(struct gpio_desc *desc)
262 EXPORT_SYMBOL_GPL(gpiod_to_gpio_device);
265 * gpio_device_get_base() - Get the base GPIO number allocated by this device
269 * First GPIO number in the global GPIO numberspace for this device.
271 int gpio_device_get_base(struct gpio_device *gdev)
275 EXPORT_SYMBOL_GPL(gpio_device_get_base);
278 * gpio_device_get_label() - Get the label of this GPIO device
282 * Pointer to the string containing the GPIO device label. The string's
283 * lifetime is tied to that of the underlying GPIO device.
285 const char *gpio_device_get_label(struct gpio_device *gdev)
289 EXPORT_SYMBOL(gpio_device_get_label);
292 * gpio_device_get_chip() - Get the gpio_chip implementation of this GPIO device
296 * Address of the GPIO chip backing this device.
299 * Until we can get rid of all non-driver users of struct gpio_chip, we must
300 * provide a way of retrieving the pointer to it from struct gpio_device. This
301 * is *NOT* safe as the GPIO API is considered to be hot-unpluggable and the
302 * chip can dissapear at any moment (unlike reference-counted struct
305 * Use at your own risk.
307 struct gpio_chip *gpio_device_get_chip(struct gpio_device *gdev)
309 return rcu_dereference_check(gdev->chip, 1);
311 EXPORT_SYMBOL_GPL(gpio_device_get_chip);
313 /* dynamic allocation of GPIOs, e.g. on a hotplugged device */
314 static int gpiochip_find_base_unlocked(int ngpio)
316 struct gpio_device *gdev;
317 int base = GPIO_DYNAMIC_BASE;
319 list_for_each_entry_srcu(gdev, &gpio_devices, list,
320 lockdep_is_held(&gpio_devices_lock)) {
321 /* found a free space? */
322 if (gdev->base >= base + ngpio)
324 /* nope, check the space right after the chip */
325 base = gdev->base + gdev->ngpio;
326 if (base < GPIO_DYNAMIC_BASE)
327 base = GPIO_DYNAMIC_BASE;
330 if (gpio_is_valid(base)) {
331 pr_debug("%s: found new base at %d\n", __func__, base);
334 pr_err("%s: cannot find free range\n", __func__);
340 * gpiod_get_direction - return the current direction of a GPIO
341 * @desc: GPIO to get the direction of
343 * Returns 0 for output, 1 for input, or an error code in case of error.
345 * This function may sleep if gpiod_cansleep() is true.
347 int gpiod_get_direction(struct gpio_desc *desc)
354 * We cannot use VALIDATE_DESC() as we must not return 0 for a NULL
355 * descriptor like we usually do.
357 if (!desc || IS_ERR(desc))
360 CLASS(gpio_chip_guard, guard)(desc);
364 offset = gpio_chip_hwgpio(desc);
365 flags = READ_ONCE(desc->flags);
368 * Open drain emulation using input mode may incorrectly report
369 * input here, fix that up.
371 if (test_bit(FLAG_OPEN_DRAIN, &flags) &&
372 test_bit(FLAG_IS_OUT, &flags))
375 if (!guard.gc->get_direction)
378 ret = guard.gc->get_direction(guard.gc, offset);
382 /* GPIOF_DIR_IN or other positive, otherwise GPIOF_DIR_OUT */
386 assign_bit(FLAG_IS_OUT, &flags, !ret);
387 WRITE_ONCE(desc->flags, flags);
391 EXPORT_SYMBOL_GPL(gpiod_get_direction);
394 * Add a new chip to the global chips list, keeping the list of chips sorted
395 * by range(means [base, base + ngpio - 1]) order.
397 * Return -EBUSY if the new chip overlaps with some other chip's integer
400 static int gpiodev_add_to_list_unlocked(struct gpio_device *gdev)
402 struct gpio_device *prev, *next;
404 lockdep_assert_held(&gpio_devices_lock);
406 if (list_empty(&gpio_devices)) {
407 /* initial entry in list */
408 list_add_tail_rcu(&gdev->list, &gpio_devices);
412 next = list_first_entry(&gpio_devices, struct gpio_device, list);
413 if (gdev->base + gdev->ngpio <= next->base) {
414 /* add before first entry */
415 list_add_rcu(&gdev->list, &gpio_devices);
419 prev = list_last_entry(&gpio_devices, struct gpio_device, list);
420 if (prev->base + prev->ngpio <= gdev->base) {
421 /* add behind last entry */
422 list_add_tail_rcu(&gdev->list, &gpio_devices);
426 list_for_each_entry_safe(prev, next, &gpio_devices, list) {
427 /* at the end of the list */
428 if (&next->list == &gpio_devices)
431 /* add between prev and next */
432 if (prev->base + prev->ngpio <= gdev->base
433 && gdev->base + gdev->ngpio <= next->base) {
434 list_add_rcu(&gdev->list, &prev->list);
439 synchronize_srcu(&gpio_devices_srcu);
445 * Convert a GPIO name to its descriptor
446 * Note that there is no guarantee that GPIO names are globally unique!
447 * Hence this function will return, if it exists, a reference to the first GPIO
448 * line found that matches the given name.
450 static struct gpio_desc *gpio_name_to_desc(const char * const name)
452 struct gpio_device *gdev;
453 struct gpio_desc *desc;
454 struct gpio_chip *gc;
459 guard(srcu)(&gpio_devices_srcu);
461 list_for_each_entry_srcu(gdev, &gpio_devices, list,
462 srcu_read_lock_held(&gpio_devices_srcu)) {
463 guard(srcu)(&gdev->srcu);
465 gc = srcu_dereference(gdev->chip, &gdev->srcu);
469 for_each_gpio_desc(gc, desc) {
470 if (desc->name && !strcmp(desc->name, name))
479 * Take the names from gc->names and assign them to their GPIO descriptors.
480 * Warn if a name is already used for a GPIO line on a different GPIO chip.
483 * 1. Non-unique names are still accepted,
484 * 2. Name collisions within the same GPIO chip are not reported.
486 static int gpiochip_set_desc_names(struct gpio_chip *gc)
488 struct gpio_device *gdev = gc->gpiodev;
491 /* First check all names if they are unique */
492 for (i = 0; i != gc->ngpio; ++i) {
493 struct gpio_desc *gpio;
495 gpio = gpio_name_to_desc(gc->names[i]);
498 "Detected name collision for GPIO name '%s'\n",
502 /* Then add all names to the GPIO descriptors */
503 for (i = 0; i != gc->ngpio; ++i)
504 gdev->descs[i].name = gc->names[i];
510 * gpiochip_set_names - Set GPIO line names using device properties
511 * @chip: GPIO chip whose lines should be named, if possible
513 * Looks for device property "gpio-line-names" and if it exists assigns
514 * GPIO line names for the chip. The memory allocated for the assigned
515 * names belong to the underlying firmware node and should not be released
518 static int gpiochip_set_names(struct gpio_chip *chip)
520 struct gpio_device *gdev = chip->gpiodev;
521 struct device *dev = &gdev->dev;
526 count = device_property_string_array_count(dev, "gpio-line-names");
531 * When offset is set in the driver side we assume the driver internally
532 * is using more than one gpiochip per the same device. We have to stop
533 * setting friendly names if the specified ones with 'gpio-line-names'
534 * are less than the offset in the device itself. This means all the
535 * lines are not present for every single pin within all the internal
538 if (count <= chip->offset) {
539 dev_warn(dev, "gpio-line-names too short (length %d), cannot map names for the gpiochip at offset %u\n",
540 count, chip->offset);
544 names = kcalloc(count, sizeof(*names), GFP_KERNEL);
548 ret = device_property_read_string_array(dev, "gpio-line-names",
551 dev_warn(dev, "failed to read GPIO line names\n");
557 * When more that one gpiochip per device is used, 'count' can
558 * contain at most number gpiochips x chip->ngpio. We have to
559 * correctly distribute all defined lines taking into account
560 * chip->offset as starting point from where we will assign
561 * the names to pins from the 'names' array. Since property
562 * 'gpio-line-names' cannot contains gaps, we have to be sure
563 * we only assign those pins that really exists since chip->ngpio
564 * can be different of the chip->offset.
566 count = (count > chip->offset) ? count - chip->offset : count;
567 if (count > chip->ngpio)
570 for (i = 0; i < count; i++) {
572 * Allow overriding "fixed" names provided by the GPIO
573 * provider. The "fixed" names are more often than not
574 * generic and less informative than the names given in
577 if (names[chip->offset + i] && names[chip->offset + i][0])
578 gdev->descs[i].name = names[chip->offset + i];
586 static unsigned long *gpiochip_allocate_mask(struct gpio_chip *gc)
590 p = bitmap_alloc(gc->ngpio, GFP_KERNEL);
594 /* Assume by default all GPIOs are valid */
595 bitmap_fill(p, gc->ngpio);
600 static void gpiochip_free_mask(unsigned long **p)
606 static unsigned int gpiochip_count_reserved_ranges(struct gpio_chip *gc)
608 struct device *dev = &gc->gpiodev->dev;
611 /* Format is "start, count, ..." */
612 size = device_property_count_u32(dev, "gpio-reserved-ranges");
613 if (size > 0 && size % 2 == 0)
619 static int gpiochip_apply_reserved_ranges(struct gpio_chip *gc)
621 struct device *dev = &gc->gpiodev->dev;
626 size = gpiochip_count_reserved_ranges(gc);
630 ranges = kmalloc_array(size, sizeof(*ranges), GFP_KERNEL);
634 ret = device_property_read_u32_array(dev, "gpio-reserved-ranges",
642 u32 count = ranges[--size];
643 u32 start = ranges[--size];
645 if (start >= gc->ngpio || start + count > gc->ngpio)
648 bitmap_clear(gc->valid_mask, start, count);
655 static int gpiochip_init_valid_mask(struct gpio_chip *gc)
659 if (!(gpiochip_count_reserved_ranges(gc) || gc->init_valid_mask))
662 gc->valid_mask = gpiochip_allocate_mask(gc);
666 ret = gpiochip_apply_reserved_ranges(gc);
670 if (gc->init_valid_mask)
671 return gc->init_valid_mask(gc,
678 static void gpiochip_free_valid_mask(struct gpio_chip *gc)
680 gpiochip_free_mask(&gc->valid_mask);
683 static int gpiochip_add_pin_ranges(struct gpio_chip *gc)
686 * Device Tree platforms are supposed to use "gpio-ranges"
687 * property. This check ensures that the ->add_pin_ranges()
688 * won't be called for them.
690 if (device_property_present(&gc->gpiodev->dev, "gpio-ranges"))
693 if (gc->add_pin_ranges)
694 return gc->add_pin_ranges(gc);
699 bool gpiochip_line_is_valid(const struct gpio_chip *gc,
702 /* No mask means all valid */
703 if (likely(!gc->valid_mask))
705 return test_bit(offset, gc->valid_mask);
707 EXPORT_SYMBOL_GPL(gpiochip_line_is_valid);
709 static void gpiodev_release(struct device *dev)
711 struct gpio_device *gdev = to_gpio_device(dev);
713 /* Call pending kfree()s for descriptor labels. */
714 synchronize_srcu(&gdev->desc_srcu);
715 cleanup_srcu_struct(&gdev->desc_srcu);
717 ida_free(&gpio_ida, gdev->id);
718 kfree_const(gdev->label);
720 cleanup_srcu_struct(&gdev->srcu);
724 static const struct device_type gpio_dev_type = {
726 .release = gpiodev_release,
729 #ifdef CONFIG_GPIO_CDEV
730 #define gcdev_register(gdev, devt) gpiolib_cdev_register((gdev), (devt))
731 #define gcdev_unregister(gdev) gpiolib_cdev_unregister((gdev))
734 * gpiolib_cdev_register() indirectly calls device_add(), which is still
735 * required even when cdev is not selected.
737 #define gcdev_register(gdev, devt) device_add(&(gdev)->dev)
738 #define gcdev_unregister(gdev) device_del(&(gdev)->dev)
741 static int gpiochip_setup_dev(struct gpio_device *gdev)
743 struct fwnode_handle *fwnode = dev_fwnode(&gdev->dev);
746 device_initialize(&gdev->dev);
749 * If fwnode doesn't belong to another device, it's safe to clear its
752 if (fwnode && !fwnode->dev)
753 fwnode_dev_initialized(fwnode, false);
755 ret = gcdev_register(gdev, gpio_devt);
759 ret = gpiochip_sysfs_register(gdev);
761 goto err_remove_device;
763 dev_dbg(&gdev->dev, "registered GPIOs %d to %d on %s\n", gdev->base,
764 gdev->base + gdev->ngpio - 1, gdev->label);
769 gcdev_unregister(gdev);
773 static void gpiochip_machine_hog(struct gpio_chip *gc, struct gpiod_hog *hog)
775 struct gpio_desc *desc;
778 desc = gpiochip_get_desc(gc, hog->chip_hwnum);
780 chip_err(gc, "%s: unable to get GPIO desc: %ld\n", __func__,
785 rv = gpiod_hog(desc, hog->line_name, hog->lflags, hog->dflags);
787 gpiod_err(desc, "%s: unable to hog GPIO line (%s:%u): %d\n",
788 __func__, gc->label, hog->chip_hwnum, rv);
791 static void machine_gpiochip_add(struct gpio_chip *gc)
793 struct gpiod_hog *hog;
795 mutex_lock(&gpio_machine_hogs_mutex);
797 list_for_each_entry(hog, &gpio_machine_hogs, list) {
798 if (!strcmp(gc->label, hog->chip_label))
799 gpiochip_machine_hog(gc, hog);
802 mutex_unlock(&gpio_machine_hogs_mutex);
805 static void gpiochip_setup_devs(void)
807 struct gpio_device *gdev;
810 guard(srcu)(&gpio_devices_srcu);
812 list_for_each_entry_srcu(gdev, &gpio_devices, list,
813 srcu_read_lock_held(&gpio_devices_srcu)) {
814 ret = gpiochip_setup_dev(gdev);
817 "Failed to initialize gpio device (%d)\n", ret);
821 static void gpiochip_set_data(struct gpio_chip *gc, void *data)
823 gc->gpiodev->data = data;
827 * gpiochip_get_data() - get per-subdriver data for the chip
831 * The per-subdriver data for the chip.
833 void *gpiochip_get_data(struct gpio_chip *gc)
835 return gc->gpiodev->data;
837 EXPORT_SYMBOL_GPL(gpiochip_get_data);
839 int gpiochip_get_ngpios(struct gpio_chip *gc, struct device *dev)
841 u32 ngpios = gc->ngpio;
845 ret = device_property_read_u32(dev, "ngpios", &ngpios);
848 * -ENODATA means that there is no property found and
849 * we want to issue the error message to the user.
850 * Besides that, we want to return different error code
851 * to state that supplied value is not valid.
860 if (gc->ngpio == 0) {
861 chip_err(gc, "tried to insert a GPIO chip with zero lines\n");
865 if (gc->ngpio > FASTPATH_NGPIO)
866 chip_warn(gc, "line cnt %u is greater than fast path cnt %u\n",
867 gc->ngpio, FASTPATH_NGPIO);
871 EXPORT_SYMBOL_GPL(gpiochip_get_ngpios);
873 int gpiochip_add_data_with_key(struct gpio_chip *gc, void *data,
874 struct lock_class_key *lock_key,
875 struct lock_class_key *request_key)
877 struct gpio_device *gdev;
878 unsigned int desc_index;
883 * First: allocate and populate the internal stat container, and
884 * set up the struct device.
886 gdev = kzalloc(sizeof(*gdev), GFP_KERNEL);
890 gdev->dev.type = &gpio_dev_type;
891 gdev->dev.bus = &gpio_bus_type;
892 gdev->dev.parent = gc->parent;
893 rcu_assign_pointer(gdev->chip, gc);
896 gpiochip_set_data(gc, data);
899 * If the calling driver did not initialize firmware node,
900 * do it here using the parent device, if any.
903 device_set_node(&gdev->dev, gc->fwnode);
905 device_set_node(&gdev->dev, dev_fwnode(gc->parent));
907 gdev->id = ida_alloc(&gpio_ida, GFP_KERNEL);
913 ret = dev_set_name(&gdev->dev, GPIOCHIP_NAME "%d", gdev->id);
917 if (gc->parent && gc->parent->driver)
918 gdev->owner = gc->parent->driver->owner;
920 /* TODO: remove chip->owner */
921 gdev->owner = gc->owner;
923 gdev->owner = THIS_MODULE;
925 ret = gpiochip_get_ngpios(gc, &gdev->dev);
927 goto err_free_dev_name;
929 gdev->descs = kcalloc(gc->ngpio, sizeof(*gdev->descs), GFP_KERNEL);
932 goto err_free_dev_name;
935 gdev->label = kstrdup_const(gc->label ?: "unknown", GFP_KERNEL);
941 gdev->ngpio = gc->ngpio;
942 gdev->can_sleep = gc->can_sleep;
944 scoped_guard(mutex, &gpio_devices_lock) {
946 * TODO: this allocates a Linux GPIO number base in the global
947 * GPIO numberspace for this chip. In the long run we want to
948 * get *rid* of this numberspace and use only descriptors, but
949 * it may be a pipe dream. It will not happen before we get rid
950 * of the sysfs interface anyways.
954 base = gpiochip_find_base_unlocked(gc->ngpio);
962 * TODO: it should not be necessary to reflect the
963 * assigned base outside of the GPIO subsystem. Go over
964 * drivers and see if anyone makes use of this, else
965 * drop this and assign a poison instead.
970 "Static allocation of GPIO base is deprecated, use dynamic allocation.\n");
975 ret = gpiodev_add_to_list_unlocked(gdev);
977 chip_err(gc, "GPIO integer space overlap, cannot add chip\n");
982 for (desc_index = 0; desc_index < gc->ngpio; desc_index++)
983 gdev->descs[desc_index].gdev = gdev;
985 BLOCKING_INIT_NOTIFIER_HEAD(&gdev->line_state_notifier);
986 BLOCKING_INIT_NOTIFIER_HEAD(&gdev->device_notifier);
988 ret = init_srcu_struct(&gdev->srcu);
990 goto err_remove_from_list;
992 ret = init_srcu_struct(&gdev->desc_srcu);
994 goto err_cleanup_gdev_srcu;
996 #ifdef CONFIG_PINCTRL
997 INIT_LIST_HEAD(&gdev->pin_ranges);
1001 ret = gpiochip_set_desc_names(gc);
1003 goto err_cleanup_desc_srcu;
1005 ret = gpiochip_set_names(gc);
1007 goto err_cleanup_desc_srcu;
1009 ret = gpiochip_init_valid_mask(gc);
1011 goto err_cleanup_desc_srcu;
1013 for (desc_index = 0; desc_index < gc->ngpio; desc_index++) {
1014 struct gpio_desc *desc = &gdev->descs[desc_index];
1016 if (gc->get_direction && gpiochip_line_is_valid(gc, desc_index)) {
1017 assign_bit(FLAG_IS_OUT,
1018 &desc->flags, !gc->get_direction(gc, desc_index));
1020 assign_bit(FLAG_IS_OUT,
1021 &desc->flags, !gc->direction_input);
1025 ret = of_gpiochip_add(gc);
1027 goto err_free_valid_mask;
1029 ret = gpiochip_add_pin_ranges(gc);
1031 goto err_remove_of_chip;
1033 acpi_gpiochip_add(gc);
1035 machine_gpiochip_add(gc);
1037 ret = gpiochip_irqchip_init_valid_mask(gc);
1041 ret = gpiochip_irqchip_init_hw(gc);
1043 goto err_remove_irqchip_mask;
1045 ret = gpiochip_add_irqchip(gc, lock_key, request_key);
1047 goto err_remove_irqchip_mask;
1050 * By first adding the chardev, and then adding the device,
1051 * we get a device node entry in sysfs under
1052 * /sys/bus/gpio/devices/gpiochipN/dev that can be used for
1053 * coldplug of device nodes and other udev business.
1054 * We can do this only if gpiolib has been initialized.
1055 * Otherwise, defer until later.
1057 if (gpiolib_initialized) {
1058 ret = gpiochip_setup_dev(gdev);
1060 goto err_remove_irqchip;
1065 gpiochip_irqchip_remove(gc);
1066 err_remove_irqchip_mask:
1067 gpiochip_irqchip_free_valid_mask(gc);
1069 gpiochip_free_hogs(gc);
1070 acpi_gpiochip_remove(gc);
1071 gpiochip_remove_pin_ranges(gc);
1073 of_gpiochip_remove(gc);
1074 err_free_valid_mask:
1075 gpiochip_free_valid_mask(gc);
1076 err_cleanup_desc_srcu:
1077 cleanup_srcu_struct(&gdev->desc_srcu);
1078 err_cleanup_gdev_srcu:
1079 cleanup_srcu_struct(&gdev->srcu);
1080 err_remove_from_list:
1081 scoped_guard(mutex, &gpio_devices_lock)
1082 list_del_rcu(&gdev->list);
1083 synchronize_srcu(&gpio_devices_srcu);
1084 if (gdev->dev.release) {
1085 /* release() has been registered by gpiochip_setup_dev() */
1086 gpio_device_put(gdev);
1087 goto err_print_message;
1090 kfree_const(gdev->label);
1094 kfree(dev_name(&gdev->dev));
1096 ida_free(&gpio_ida, gdev->id);
1100 /* failures here can mean systems won't boot... */
1101 if (ret != -EPROBE_DEFER) {
1102 pr_err("%s: GPIOs %d..%d (%s) failed to register, %d\n", __func__,
1103 base, base + (int)gc->ngpio - 1,
1104 gc->label ? : "generic", ret);
1108 EXPORT_SYMBOL_GPL(gpiochip_add_data_with_key);
1111 * gpiochip_remove() - unregister a gpio_chip
1112 * @gc: the chip to unregister
1114 * A gpio_chip with any GPIOs still requested may not be removed.
1116 void gpiochip_remove(struct gpio_chip *gc)
1118 struct gpio_device *gdev = gc->gpiodev;
1120 /* FIXME: should the legacy sysfs handling be moved to gpio_device? */
1121 gpiochip_sysfs_unregister(gdev);
1122 gpiochip_free_hogs(gc);
1124 scoped_guard(mutex, &gpio_devices_lock)
1125 list_del_rcu(&gdev->list);
1126 synchronize_srcu(&gpio_devices_srcu);
1128 /* Numb the device, cancelling all outstanding operations */
1129 rcu_assign_pointer(gdev->chip, NULL);
1130 synchronize_srcu(&gdev->srcu);
1131 gpiochip_irqchip_remove(gc);
1132 acpi_gpiochip_remove(gc);
1133 of_gpiochip_remove(gc);
1134 gpiochip_remove_pin_ranges(gc);
1135 gpiochip_free_valid_mask(gc);
1137 * We accept no more calls into the driver from this point, so
1138 * NULL the driver data pointer.
1140 gpiochip_set_data(gc, NULL);
1143 * The gpiochip side puts its use of the device to rest here:
1144 * if there are no userspace clients, the chardev and device will
1145 * be removed, else it will be dangling until the last user is
1148 gcdev_unregister(gdev);
1149 gpio_device_put(gdev);
1151 EXPORT_SYMBOL_GPL(gpiochip_remove);
1154 * gpio_device_find() - find a specific GPIO device
1155 * @data: data to pass to match function
1156 * @match: Callback function to check gpio_chip
1159 * New reference to struct gpio_device.
1161 * Similar to bus_find_device(). It returns a reference to a gpio_device as
1162 * determined by a user supplied @match callback. The callback should return
1163 * 0 if the device doesn't match and non-zero if it does. If the callback
1164 * returns non-zero, this function will return to the caller and not iterate
1165 * over any more gpio_devices.
1167 * The callback takes the GPIO chip structure as argument. During the execution
1168 * of the callback function the chip is protected from being freed. TODO: This
1169 * actually has yet to be implemented.
1171 * If the function returns non-NULL, the returned reference must be freed by
1172 * the caller using gpio_device_put().
1174 struct gpio_device *gpio_device_find(const void *data,
1175 int (*match)(struct gpio_chip *gc,
1178 struct gpio_device *gdev;
1179 struct gpio_chip *gc;
1182 * Not yet but in the future the spinlock below will become a mutex.
1183 * Annotate this function before anyone tries to use it in interrupt
1184 * context like it happened with gpiochip_find().
1188 guard(srcu)(&gpio_devices_srcu);
1190 list_for_each_entry_srcu(gdev, &gpio_devices, list,
1191 srcu_read_lock_held(&gpio_devices_srcu)) {
1192 if (!device_is_registered(&gdev->dev))
1195 guard(srcu)(&gdev->srcu);
1197 gc = srcu_dereference(gdev->chip, &gdev->srcu);
1199 if (gc && match(gc, data))
1200 return gpio_device_get(gdev);
1205 EXPORT_SYMBOL_GPL(gpio_device_find);
1207 static int gpio_chip_match_by_label(struct gpio_chip *gc, const void *label)
1209 return gc->label && !strcmp(gc->label, label);
1213 * gpio_device_find_by_label() - wrapper around gpio_device_find() finding the
1214 * GPIO device by its backing chip's label
1215 * @label: Label to lookup
1218 * Reference to the GPIO device or NULL. Reference must be released with
1219 * gpio_device_put().
1221 struct gpio_device *gpio_device_find_by_label(const char *label)
1223 return gpio_device_find((void *)label, gpio_chip_match_by_label);
1225 EXPORT_SYMBOL_GPL(gpio_device_find_by_label);
1227 static int gpio_chip_match_by_fwnode(struct gpio_chip *gc, const void *fwnode)
1229 return device_match_fwnode(&gc->gpiodev->dev, fwnode);
1233 * gpio_device_find_by_fwnode() - wrapper around gpio_device_find() finding
1234 * the GPIO device by its fwnode
1235 * @fwnode: Firmware node to lookup
1238 * Reference to the GPIO device or NULL. Reference must be released with
1239 * gpio_device_put().
1241 struct gpio_device *gpio_device_find_by_fwnode(const struct fwnode_handle *fwnode)
1243 return gpio_device_find((void *)fwnode, gpio_chip_match_by_fwnode);
1245 EXPORT_SYMBOL_GPL(gpio_device_find_by_fwnode);
1248 * gpio_device_get() - Increase the reference count of this GPIO device
1249 * @gdev: GPIO device to increase the refcount for
1254 struct gpio_device *gpio_device_get(struct gpio_device *gdev)
1256 return to_gpio_device(get_device(&gdev->dev));
1258 EXPORT_SYMBOL_GPL(gpio_device_get);
1261 * gpio_device_put() - Decrease the reference count of this GPIO device and
1262 * possibly free all resources associated with it.
1263 * @gdev: GPIO device to decrease the reference count for
1265 void gpio_device_put(struct gpio_device *gdev)
1267 put_device(&gdev->dev);
1269 EXPORT_SYMBOL_GPL(gpio_device_put);
1272 * gpio_device_to_device() - Retrieve the address of the underlying struct
1274 * @gdev: GPIO device for which to return the address.
1276 * This does not increase the reference count of the GPIO device nor the
1277 * underlying struct device.
1280 * Address of struct device backing this GPIO device.
1282 struct device *gpio_device_to_device(struct gpio_device *gdev)
1286 EXPORT_SYMBOL_GPL(gpio_device_to_device);
1288 #ifdef CONFIG_GPIOLIB_IRQCHIP
1291 * The following is irqchip helper code for gpiochips.
1294 static int gpiochip_irqchip_init_hw(struct gpio_chip *gc)
1296 struct gpio_irq_chip *girq = &gc->irq;
1301 return girq->init_hw(gc);
1304 static int gpiochip_irqchip_init_valid_mask(struct gpio_chip *gc)
1306 struct gpio_irq_chip *girq = &gc->irq;
1308 if (!girq->init_valid_mask)
1311 girq->valid_mask = gpiochip_allocate_mask(gc);
1312 if (!girq->valid_mask)
1315 girq->init_valid_mask(gc, girq->valid_mask, gc->ngpio);
1320 static void gpiochip_irqchip_free_valid_mask(struct gpio_chip *gc)
1322 gpiochip_free_mask(&gc->irq.valid_mask);
1325 static bool gpiochip_irqchip_irq_valid(const struct gpio_chip *gc,
1326 unsigned int offset)
1328 if (!gpiochip_line_is_valid(gc, offset))
1330 /* No mask means all valid */
1331 if (likely(!gc->irq.valid_mask))
1333 return test_bit(offset, gc->irq.valid_mask);
1336 #ifdef CONFIG_IRQ_DOMAIN_HIERARCHY
1339 * gpiochip_set_hierarchical_irqchip() - connects a hierarchical irqchip
1341 * @gc: the gpiochip to set the irqchip hierarchical handler to
1342 * @irqchip: the irqchip to handle this level of the hierarchy, the interrupt
1343 * will then percolate up to the parent
1345 static void gpiochip_set_hierarchical_irqchip(struct gpio_chip *gc,
1346 struct irq_chip *irqchip)
1348 /* DT will deal with mapping each IRQ as we go along */
1349 if (is_of_node(gc->irq.fwnode))
1353 * This is for legacy and boardfile "irqchip" fwnodes: allocate
1354 * irqs upfront instead of dynamically since we don't have the
1355 * dynamic type of allocation that hardware description languages
1356 * provide. Once all GPIO drivers using board files are gone from
1357 * the kernel we can delete this code, but for a transitional period
1358 * it is necessary to keep this around.
1360 if (is_fwnode_irqchip(gc->irq.fwnode)) {
1364 for (i = 0; i < gc->ngpio; i++) {
1365 struct irq_fwspec fwspec;
1366 unsigned int parent_hwirq;
1367 unsigned int parent_type;
1368 struct gpio_irq_chip *girq = &gc->irq;
1371 * We call the child to parent translation function
1372 * only to check if the child IRQ is valid or not.
1373 * Just pick the rising edge type here as that is what
1374 * we likely need to support.
1376 ret = girq->child_to_parent_hwirq(gc, i,
1377 IRQ_TYPE_EDGE_RISING,
1381 chip_err(gc, "skip set-up on hwirq %d\n",
1386 fwspec.fwnode = gc->irq.fwnode;
1387 /* This is the hwirq for the GPIO line side of things */
1388 fwspec.param[0] = girq->child_offset_to_irq(gc, i);
1389 /* Just pick something */
1390 fwspec.param[1] = IRQ_TYPE_EDGE_RISING;
1391 fwspec.param_count = 2;
1392 ret = irq_domain_alloc_irqs(gc->irq.domain, 1,
1393 NUMA_NO_NODE, &fwspec);
1396 "can not allocate irq for GPIO line %d parent hwirq %d in hierarchy domain: %d\n",
1403 chip_err(gc, "%s unknown fwnode type proceed anyway\n", __func__);
1408 static int gpiochip_hierarchy_irq_domain_translate(struct irq_domain *d,
1409 struct irq_fwspec *fwspec,
1410 unsigned long *hwirq,
1413 /* We support standard DT translation */
1414 if (is_of_node(fwspec->fwnode) && fwspec->param_count == 2) {
1415 return irq_domain_translate_twocell(d, fwspec, hwirq, type);
1418 /* This is for board files and others not using DT */
1419 if (is_fwnode_irqchip(fwspec->fwnode)) {
1422 ret = irq_domain_translate_twocell(d, fwspec, hwirq, type);
1425 WARN_ON(*type == IRQ_TYPE_NONE);
1431 static int gpiochip_hierarchy_irq_domain_alloc(struct irq_domain *d,
1433 unsigned int nr_irqs,
1436 struct gpio_chip *gc = d->host_data;
1437 irq_hw_number_t hwirq;
1438 unsigned int type = IRQ_TYPE_NONE;
1439 struct irq_fwspec *fwspec = data;
1440 union gpio_irq_fwspec gpio_parent_fwspec = {};
1441 unsigned int parent_hwirq;
1442 unsigned int parent_type;
1443 struct gpio_irq_chip *girq = &gc->irq;
1447 * The nr_irqs parameter is always one except for PCI multi-MSI
1448 * so this should not happen.
1450 WARN_ON(nr_irqs != 1);
1452 ret = gc->irq.child_irq_domain_ops.translate(d, fwspec, &hwirq, &type);
1456 chip_dbg(gc, "allocate IRQ %d, hwirq %lu\n", irq, hwirq);
1458 ret = girq->child_to_parent_hwirq(gc, hwirq, type,
1459 &parent_hwirq, &parent_type);
1461 chip_err(gc, "can't look up hwirq %lu\n", hwirq);
1464 chip_dbg(gc, "found parent hwirq %u\n", parent_hwirq);
1467 * We set handle_bad_irq because the .set_type() should
1468 * always be invoked and set the right type of handler.
1470 irq_domain_set_info(d,
1479 /* This parent only handles asserted level IRQs */
1480 ret = girq->populate_parent_alloc_arg(gc, &gpio_parent_fwspec,
1481 parent_hwirq, parent_type);
1485 chip_dbg(gc, "alloc_irqs_parent for %d parent hwirq %d\n",
1487 irq_set_lockdep_class(irq, gc->irq.lock_key, gc->irq.request_key);
1488 ret = irq_domain_alloc_irqs_parent(d, irq, 1, &gpio_parent_fwspec);
1490 * If the parent irqdomain is msi, the interrupts have already
1491 * been allocated, so the EEXIST is good.
1493 if (irq_domain_is_msi(d->parent) && (ret == -EEXIST))
1497 "failed to allocate parent hwirq %d for hwirq %lu\n",
1498 parent_hwirq, hwirq);
1503 static unsigned int gpiochip_child_offset_to_irq_noop(struct gpio_chip *gc,
1504 unsigned int offset)
1510 * gpiochip_irq_domain_activate() - Lock a GPIO to be used as an IRQ
1511 * @domain: The IRQ domain used by this IRQ chip
1512 * @data: Outermost irq_data associated with the IRQ
1513 * @reserve: If set, only reserve an interrupt vector instead of assigning one
1515 * This function is a wrapper that calls gpiochip_lock_as_irq() and is to be
1516 * used as the activate function for the &struct irq_domain_ops. The host_data
1517 * for the IRQ domain must be the &struct gpio_chip.
1519 static int gpiochip_irq_domain_activate(struct irq_domain *domain,
1520 struct irq_data *data, bool reserve)
1522 struct gpio_chip *gc = domain->host_data;
1523 unsigned int hwirq = irqd_to_hwirq(data);
1525 return gpiochip_lock_as_irq(gc, hwirq);
1529 * gpiochip_irq_domain_deactivate() - Unlock a GPIO used as an IRQ
1530 * @domain: The IRQ domain used by this IRQ chip
1531 * @data: Outermost irq_data associated with the IRQ
1533 * This function is a wrapper that will call gpiochip_unlock_as_irq() and is to
1534 * be used as the deactivate function for the &struct irq_domain_ops. The
1535 * host_data for the IRQ domain must be the &struct gpio_chip.
1537 static void gpiochip_irq_domain_deactivate(struct irq_domain *domain,
1538 struct irq_data *data)
1540 struct gpio_chip *gc = domain->host_data;
1541 unsigned int hwirq = irqd_to_hwirq(data);
1543 return gpiochip_unlock_as_irq(gc, hwirq);
1546 static void gpiochip_hierarchy_setup_domain_ops(struct irq_domain_ops *ops)
1548 ops->activate = gpiochip_irq_domain_activate;
1549 ops->deactivate = gpiochip_irq_domain_deactivate;
1550 ops->alloc = gpiochip_hierarchy_irq_domain_alloc;
1553 * We only allow overriding the translate() and free() functions for
1554 * hierarchical chips, and this should only be done if the user
1555 * really need something other than 1:1 translation for translate()
1556 * callback and free if user wants to free up any resources which
1557 * were allocated during callbacks, for example populate_parent_alloc_arg.
1559 if (!ops->translate)
1560 ops->translate = gpiochip_hierarchy_irq_domain_translate;
1562 ops->free = irq_domain_free_irqs_common;
1565 static struct irq_domain *gpiochip_hierarchy_create_domain(struct gpio_chip *gc)
1567 struct irq_domain *domain;
1569 if (!gc->irq.child_to_parent_hwirq ||
1571 chip_err(gc, "missing irqdomain vital data\n");
1572 return ERR_PTR(-EINVAL);
1575 if (!gc->irq.child_offset_to_irq)
1576 gc->irq.child_offset_to_irq = gpiochip_child_offset_to_irq_noop;
1578 if (!gc->irq.populate_parent_alloc_arg)
1579 gc->irq.populate_parent_alloc_arg =
1580 gpiochip_populate_parent_fwspec_twocell;
1582 gpiochip_hierarchy_setup_domain_ops(&gc->irq.child_irq_domain_ops);
1584 domain = irq_domain_create_hierarchy(
1585 gc->irq.parent_domain,
1589 &gc->irq.child_irq_domain_ops,
1593 return ERR_PTR(-ENOMEM);
1595 gpiochip_set_hierarchical_irqchip(gc, gc->irq.chip);
1600 static bool gpiochip_hierarchy_is_hierarchical(struct gpio_chip *gc)
1602 return !!gc->irq.parent_domain;
1605 int gpiochip_populate_parent_fwspec_twocell(struct gpio_chip *gc,
1606 union gpio_irq_fwspec *gfwspec,
1607 unsigned int parent_hwirq,
1608 unsigned int parent_type)
1610 struct irq_fwspec *fwspec = &gfwspec->fwspec;
1612 fwspec->fwnode = gc->irq.parent_domain->fwnode;
1613 fwspec->param_count = 2;
1614 fwspec->param[0] = parent_hwirq;
1615 fwspec->param[1] = parent_type;
1619 EXPORT_SYMBOL_GPL(gpiochip_populate_parent_fwspec_twocell);
1621 int gpiochip_populate_parent_fwspec_fourcell(struct gpio_chip *gc,
1622 union gpio_irq_fwspec *gfwspec,
1623 unsigned int parent_hwirq,
1624 unsigned int parent_type)
1626 struct irq_fwspec *fwspec = &gfwspec->fwspec;
1628 fwspec->fwnode = gc->irq.parent_domain->fwnode;
1629 fwspec->param_count = 4;
1630 fwspec->param[0] = 0;
1631 fwspec->param[1] = parent_hwirq;
1632 fwspec->param[2] = 0;
1633 fwspec->param[3] = parent_type;
1637 EXPORT_SYMBOL_GPL(gpiochip_populate_parent_fwspec_fourcell);
1641 static struct irq_domain *gpiochip_hierarchy_create_domain(struct gpio_chip *gc)
1643 return ERR_PTR(-EINVAL);
1646 static bool gpiochip_hierarchy_is_hierarchical(struct gpio_chip *gc)
1651 #endif /* CONFIG_IRQ_DOMAIN_HIERARCHY */
1654 * gpiochip_irq_map() - maps an IRQ into a GPIO irqchip
1655 * @d: the irqdomain used by this irqchip
1656 * @irq: the global irq number used by this GPIO irqchip irq
1657 * @hwirq: the local IRQ/GPIO line offset on this gpiochip
1659 * This function will set up the mapping for a certain IRQ line on a
1660 * gpiochip by assigning the gpiochip as chip data, and using the irqchip
1661 * stored inside the gpiochip.
1663 static int gpiochip_irq_map(struct irq_domain *d, unsigned int irq,
1664 irq_hw_number_t hwirq)
1666 struct gpio_chip *gc = d->host_data;
1669 if (!gpiochip_irqchip_irq_valid(gc, hwirq))
1672 irq_set_chip_data(irq, gc);
1674 * This lock class tells lockdep that GPIO irqs are in a different
1675 * category than their parents, so it won't report false recursion.
1677 irq_set_lockdep_class(irq, gc->irq.lock_key, gc->irq.request_key);
1678 irq_set_chip_and_handler(irq, gc->irq.chip, gc->irq.handler);
1679 /* Chips that use nested thread handlers have them marked */
1680 if (gc->irq.threaded)
1681 irq_set_nested_thread(irq, 1);
1682 irq_set_noprobe(irq);
1684 if (gc->irq.num_parents == 1)
1685 ret = irq_set_parent(irq, gc->irq.parents[0]);
1686 else if (gc->irq.map)
1687 ret = irq_set_parent(irq, gc->irq.map[hwirq]);
1693 * No set-up of the hardware will happen if IRQ_TYPE_NONE
1694 * is passed as default type.
1696 if (gc->irq.default_type != IRQ_TYPE_NONE)
1697 irq_set_irq_type(irq, gc->irq.default_type);
1702 static void gpiochip_irq_unmap(struct irq_domain *d, unsigned int irq)
1704 struct gpio_chip *gc = d->host_data;
1706 if (gc->irq.threaded)
1707 irq_set_nested_thread(irq, 0);
1708 irq_set_chip_and_handler(irq, NULL, NULL);
1709 irq_set_chip_data(irq, NULL);
1712 static const struct irq_domain_ops gpiochip_domain_ops = {
1713 .map = gpiochip_irq_map,
1714 .unmap = gpiochip_irq_unmap,
1715 /* Virtually all GPIO irqchips are twocell:ed */
1716 .xlate = irq_domain_xlate_twocell,
1719 static struct irq_domain *gpiochip_simple_create_domain(struct gpio_chip *gc)
1721 struct fwnode_handle *fwnode = dev_fwnode(&gc->gpiodev->dev);
1722 struct irq_domain *domain;
1724 domain = irq_domain_create_simple(fwnode, gc->ngpio, gc->irq.first,
1725 &gpiochip_domain_ops, gc);
1727 return ERR_PTR(-EINVAL);
1732 static int gpiochip_to_irq(struct gpio_chip *gc, unsigned int offset)
1734 struct irq_domain *domain = gc->irq.domain;
1736 #ifdef CONFIG_GPIOLIB_IRQCHIP
1738 * Avoid race condition with other code, which tries to lookup
1739 * an IRQ before the irqchip has been properly registered,
1740 * i.e. while gpiochip is still being brought up.
1742 if (!gc->irq.initialized)
1743 return -EPROBE_DEFER;
1746 if (!gpiochip_irqchip_irq_valid(gc, offset))
1749 #ifdef CONFIG_IRQ_DOMAIN_HIERARCHY
1750 if (irq_domain_is_hierarchy(domain)) {
1751 struct irq_fwspec spec;
1753 spec.fwnode = domain->fwnode;
1754 spec.param_count = 2;
1755 spec.param[0] = gc->irq.child_offset_to_irq(gc, offset);
1756 spec.param[1] = IRQ_TYPE_NONE;
1758 return irq_create_fwspec_mapping(&spec);
1762 return irq_create_mapping(domain, offset);
1765 int gpiochip_irq_reqres(struct irq_data *d)
1767 struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
1768 unsigned int hwirq = irqd_to_hwirq(d);
1770 return gpiochip_reqres_irq(gc, hwirq);
1772 EXPORT_SYMBOL(gpiochip_irq_reqres);
1774 void gpiochip_irq_relres(struct irq_data *d)
1776 struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
1777 unsigned int hwirq = irqd_to_hwirq(d);
1779 gpiochip_relres_irq(gc, hwirq);
1781 EXPORT_SYMBOL(gpiochip_irq_relres);
1783 static void gpiochip_irq_mask(struct irq_data *d)
1785 struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
1786 unsigned int hwirq = irqd_to_hwirq(d);
1788 if (gc->irq.irq_mask)
1789 gc->irq.irq_mask(d);
1790 gpiochip_disable_irq(gc, hwirq);
1793 static void gpiochip_irq_unmask(struct irq_data *d)
1795 struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
1796 unsigned int hwirq = irqd_to_hwirq(d);
1798 gpiochip_enable_irq(gc, hwirq);
1799 if (gc->irq.irq_unmask)
1800 gc->irq.irq_unmask(d);
1803 static void gpiochip_irq_enable(struct irq_data *d)
1805 struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
1806 unsigned int hwirq = irqd_to_hwirq(d);
1808 gpiochip_enable_irq(gc, hwirq);
1809 gc->irq.irq_enable(d);
1812 static void gpiochip_irq_disable(struct irq_data *d)
1814 struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
1815 unsigned int hwirq = irqd_to_hwirq(d);
1817 gc->irq.irq_disable(d);
1818 gpiochip_disable_irq(gc, hwirq);
1821 static void gpiochip_set_irq_hooks(struct gpio_chip *gc)
1823 struct irq_chip *irqchip = gc->irq.chip;
1825 if (irqchip->flags & IRQCHIP_IMMUTABLE)
1828 chip_warn(gc, "not an immutable chip, please consider fixing it!\n");
1830 if (!irqchip->irq_request_resources &&
1831 !irqchip->irq_release_resources) {
1832 irqchip->irq_request_resources = gpiochip_irq_reqres;
1833 irqchip->irq_release_resources = gpiochip_irq_relres;
1835 if (WARN_ON(gc->irq.irq_enable))
1837 /* Check if the irqchip already has this hook... */
1838 if (irqchip->irq_enable == gpiochip_irq_enable ||
1839 irqchip->irq_mask == gpiochip_irq_mask) {
1841 * ...and if so, give a gentle warning that this is bad
1845 "detected irqchip that is shared with multiple gpiochips: please fix the driver.\n");
1849 if (irqchip->irq_disable) {
1850 gc->irq.irq_disable = irqchip->irq_disable;
1851 irqchip->irq_disable = gpiochip_irq_disable;
1853 gc->irq.irq_mask = irqchip->irq_mask;
1854 irqchip->irq_mask = gpiochip_irq_mask;
1857 if (irqchip->irq_enable) {
1858 gc->irq.irq_enable = irqchip->irq_enable;
1859 irqchip->irq_enable = gpiochip_irq_enable;
1861 gc->irq.irq_unmask = irqchip->irq_unmask;
1862 irqchip->irq_unmask = gpiochip_irq_unmask;
1866 static int gpiochip_irqchip_add_allocated_domain(struct gpio_chip *gc,
1867 struct irq_domain *domain,
1868 bool allocated_externally)
1874 chip_warn(gc, "to_irq is redefined in %s and you shouldn't rely on it\n", __func__);
1876 gc->to_irq = gpiochip_to_irq;
1877 gc->irq.domain = domain;
1878 gc->irq.domain_is_allocated_externally = allocated_externally;
1881 * Using barrier() here to prevent compiler from reordering
1882 * gc->irq.initialized before adding irqdomain.
1886 gc->irq.initialized = true;
1892 * gpiochip_add_irqchip() - adds an IRQ chip to a GPIO chip
1893 * @gc: the GPIO chip to add the IRQ chip to
1894 * @lock_key: lockdep class for IRQ lock
1895 * @request_key: lockdep class for IRQ request
1897 static int gpiochip_add_irqchip(struct gpio_chip *gc,
1898 struct lock_class_key *lock_key,
1899 struct lock_class_key *request_key)
1901 struct fwnode_handle *fwnode = dev_fwnode(&gc->gpiodev->dev);
1902 struct irq_chip *irqchip = gc->irq.chip;
1903 struct irq_domain *domain;
1911 if (gc->irq.parent_handler && gc->can_sleep) {
1912 chip_err(gc, "you cannot have chained interrupts on a chip that may sleep\n");
1916 type = gc->irq.default_type;
1919 * Specifying a default trigger is a terrible idea if DT or ACPI is
1920 * used to configure the interrupts, as you may end up with
1921 * conflicting triggers. Tell the user, and reset to NONE.
1923 if (WARN(fwnode && type != IRQ_TYPE_NONE,
1924 "%pfw: Ignoring %u default trigger\n", fwnode, type))
1925 type = IRQ_TYPE_NONE;
1927 gc->irq.default_type = type;
1928 gc->irq.lock_key = lock_key;
1929 gc->irq.request_key = request_key;
1931 /* If a parent irqdomain is provided, let's build a hierarchy */
1932 if (gpiochip_hierarchy_is_hierarchical(gc)) {
1933 domain = gpiochip_hierarchy_create_domain(gc);
1935 domain = gpiochip_simple_create_domain(gc);
1938 return PTR_ERR(domain);
1940 if (gc->irq.parent_handler) {
1941 for (i = 0; i < gc->irq.num_parents; i++) {
1944 if (gc->irq.per_parent_data)
1945 data = gc->irq.parent_handler_data_array[i];
1947 data = gc->irq.parent_handler_data ?: gc;
1950 * The parent IRQ chip is already using the chip_data
1951 * for this IRQ chip, so our callbacks simply use the
1954 irq_set_chained_handler_and_data(gc->irq.parents[i],
1955 gc->irq.parent_handler,
1960 gpiochip_set_irq_hooks(gc);
1962 ret = gpiochip_irqchip_add_allocated_domain(gc, domain, false);
1966 acpi_gpiochip_request_interrupts(gc);
1972 * gpiochip_irqchip_remove() - removes an irqchip added to a gpiochip
1973 * @gc: the gpiochip to remove the irqchip from
1975 * This is called only from gpiochip_remove()
1977 static void gpiochip_irqchip_remove(struct gpio_chip *gc)
1979 struct irq_chip *irqchip = gc->irq.chip;
1980 unsigned int offset;
1982 acpi_gpiochip_free_interrupts(gc);
1984 if (irqchip && gc->irq.parent_handler) {
1985 struct gpio_irq_chip *irq = &gc->irq;
1988 for (i = 0; i < irq->num_parents; i++)
1989 irq_set_chained_handler_and_data(irq->parents[i],
1993 /* Remove all IRQ mappings and delete the domain */
1994 if (!gc->irq.domain_is_allocated_externally && gc->irq.domain) {
1997 for (offset = 0; offset < gc->ngpio; offset++) {
1998 if (!gpiochip_irqchip_irq_valid(gc, offset))
2001 irq = irq_find_mapping(gc->irq.domain, offset);
2002 irq_dispose_mapping(irq);
2005 irq_domain_remove(gc->irq.domain);
2008 if (irqchip && !(irqchip->flags & IRQCHIP_IMMUTABLE)) {
2009 if (irqchip->irq_request_resources == gpiochip_irq_reqres) {
2010 irqchip->irq_request_resources = NULL;
2011 irqchip->irq_release_resources = NULL;
2013 if (irqchip->irq_enable == gpiochip_irq_enable) {
2014 irqchip->irq_enable = gc->irq.irq_enable;
2015 irqchip->irq_disable = gc->irq.irq_disable;
2018 gc->irq.irq_enable = NULL;
2019 gc->irq.irq_disable = NULL;
2020 gc->irq.chip = NULL;
2022 gpiochip_irqchip_free_valid_mask(gc);
2026 * gpiochip_irqchip_add_domain() - adds an irqdomain to a gpiochip
2027 * @gc: the gpiochip to add the irqchip to
2028 * @domain: the irqdomain to add to the gpiochip
2030 * This function adds an IRQ domain to the gpiochip.
2032 int gpiochip_irqchip_add_domain(struct gpio_chip *gc,
2033 struct irq_domain *domain)
2035 return gpiochip_irqchip_add_allocated_domain(gc, domain, true);
2037 EXPORT_SYMBOL_GPL(gpiochip_irqchip_add_domain);
2039 #else /* CONFIG_GPIOLIB_IRQCHIP */
2041 static inline int gpiochip_add_irqchip(struct gpio_chip *gc,
2042 struct lock_class_key *lock_key,
2043 struct lock_class_key *request_key)
2047 static void gpiochip_irqchip_remove(struct gpio_chip *gc) {}
2049 static inline int gpiochip_irqchip_init_hw(struct gpio_chip *gc)
2054 static inline int gpiochip_irqchip_init_valid_mask(struct gpio_chip *gc)
2058 static inline void gpiochip_irqchip_free_valid_mask(struct gpio_chip *gc)
2061 #endif /* CONFIG_GPIOLIB_IRQCHIP */
2064 * gpiochip_generic_request() - request the gpio function for a pin
2065 * @gc: the gpiochip owning the GPIO
2066 * @offset: the offset of the GPIO to request for GPIO function
2068 int gpiochip_generic_request(struct gpio_chip *gc, unsigned int offset)
2070 #ifdef CONFIG_PINCTRL
2071 if (list_empty(&gc->gpiodev->pin_ranges))
2075 return pinctrl_gpio_request(gc, offset);
2077 EXPORT_SYMBOL_GPL(gpiochip_generic_request);
2080 * gpiochip_generic_free() - free the gpio function from a pin
2081 * @gc: the gpiochip to request the gpio function for
2082 * @offset: the offset of the GPIO to free from GPIO function
2084 void gpiochip_generic_free(struct gpio_chip *gc, unsigned int offset)
2086 #ifdef CONFIG_PINCTRL
2087 if (list_empty(&gc->gpiodev->pin_ranges))
2091 pinctrl_gpio_free(gc, offset);
2093 EXPORT_SYMBOL_GPL(gpiochip_generic_free);
2096 * gpiochip_generic_config() - apply configuration for a pin
2097 * @gc: the gpiochip owning the GPIO
2098 * @offset: the offset of the GPIO to apply the configuration
2099 * @config: the configuration to be applied
2101 int gpiochip_generic_config(struct gpio_chip *gc, unsigned int offset,
2102 unsigned long config)
2104 #ifdef CONFIG_PINCTRL
2105 if (list_empty(&gc->gpiodev->pin_ranges))
2109 return pinctrl_gpio_set_config(gc, offset, config);
2111 EXPORT_SYMBOL_GPL(gpiochip_generic_config);
2113 #ifdef CONFIG_PINCTRL
2116 * gpiochip_add_pingroup_range() - add a range for GPIO <-> pin mapping
2117 * @gc: the gpiochip to add the range for
2118 * @pctldev: the pin controller to map to
2119 * @gpio_offset: the start offset in the current gpio_chip number space
2120 * @pin_group: name of the pin group inside the pin controller
2122 * Calling this function directly from a DeviceTree-supported
2123 * pinctrl driver is DEPRECATED. Please see Section 2.1 of
2124 * Documentation/devicetree/bindings/gpio/gpio.txt on how to
2125 * bind pinctrl and gpio drivers via the "gpio-ranges" property.
2127 int gpiochip_add_pingroup_range(struct gpio_chip *gc,
2128 struct pinctrl_dev *pctldev,
2129 unsigned int gpio_offset, const char *pin_group)
2131 struct gpio_pin_range *pin_range;
2132 struct gpio_device *gdev = gc->gpiodev;
2135 pin_range = kzalloc(sizeof(*pin_range), GFP_KERNEL);
2137 chip_err(gc, "failed to allocate pin ranges\n");
2141 /* Use local offset as range ID */
2142 pin_range->range.id = gpio_offset;
2143 pin_range->range.gc = gc;
2144 pin_range->range.name = gc->label;
2145 pin_range->range.base = gdev->base + gpio_offset;
2146 pin_range->pctldev = pctldev;
2148 ret = pinctrl_get_group_pins(pctldev, pin_group,
2149 &pin_range->range.pins,
2150 &pin_range->range.npins);
2156 pinctrl_add_gpio_range(pctldev, &pin_range->range);
2158 chip_dbg(gc, "created GPIO range %d->%d ==> %s PINGRP %s\n",
2159 gpio_offset, gpio_offset + pin_range->range.npins - 1,
2160 pinctrl_dev_get_devname(pctldev), pin_group);
2162 list_add_tail(&pin_range->node, &gdev->pin_ranges);
2166 EXPORT_SYMBOL_GPL(gpiochip_add_pingroup_range);
2169 * gpiochip_add_pin_range() - add a range for GPIO <-> pin mapping
2170 * @gc: the gpiochip to add the range for
2171 * @pinctl_name: the dev_name() of the pin controller to map to
2172 * @gpio_offset: the start offset in the current gpio_chip number space
2173 * @pin_offset: the start offset in the pin controller number space
2174 * @npins: the number of pins from the offset of each pin space (GPIO and
2175 * pin controller) to accumulate in this range
2178 * 0 on success, or a negative error-code on failure.
2180 * Calling this function directly from a DeviceTree-supported
2181 * pinctrl driver is DEPRECATED. Please see Section 2.1 of
2182 * Documentation/devicetree/bindings/gpio/gpio.txt on how to
2183 * bind pinctrl and gpio drivers via the "gpio-ranges" property.
2185 int gpiochip_add_pin_range(struct gpio_chip *gc, const char *pinctl_name,
2186 unsigned int gpio_offset, unsigned int pin_offset,
2189 struct gpio_pin_range *pin_range;
2190 struct gpio_device *gdev = gc->gpiodev;
2193 pin_range = kzalloc(sizeof(*pin_range), GFP_KERNEL);
2195 chip_err(gc, "failed to allocate pin ranges\n");
2199 /* Use local offset as range ID */
2200 pin_range->range.id = gpio_offset;
2201 pin_range->range.gc = gc;
2202 pin_range->range.name = gc->label;
2203 pin_range->range.base = gdev->base + gpio_offset;
2204 pin_range->range.pin_base = pin_offset;
2205 pin_range->range.npins = npins;
2206 pin_range->pctldev = pinctrl_find_and_add_gpio_range(pinctl_name,
2208 if (IS_ERR(pin_range->pctldev)) {
2209 ret = PTR_ERR(pin_range->pctldev);
2210 chip_err(gc, "could not create pin range\n");
2214 chip_dbg(gc, "created GPIO range %d->%d ==> %s PIN %d->%d\n",
2215 gpio_offset, gpio_offset + npins - 1,
2217 pin_offset, pin_offset + npins - 1);
2219 list_add_tail(&pin_range->node, &gdev->pin_ranges);
2223 EXPORT_SYMBOL_GPL(gpiochip_add_pin_range);
2226 * gpiochip_remove_pin_ranges() - remove all the GPIO <-> pin mappings
2227 * @gc: the chip to remove all the mappings for
2229 void gpiochip_remove_pin_ranges(struct gpio_chip *gc)
2231 struct gpio_pin_range *pin_range, *tmp;
2232 struct gpio_device *gdev = gc->gpiodev;
2234 list_for_each_entry_safe(pin_range, tmp, &gdev->pin_ranges, node) {
2235 list_del(&pin_range->node);
2236 pinctrl_remove_gpio_range(pin_range->pctldev,
2241 EXPORT_SYMBOL_GPL(gpiochip_remove_pin_ranges);
2243 #endif /* CONFIG_PINCTRL */
2245 /* These "optional" allocation calls help prevent drivers from stomping
2246 * on each other, and help provide better diagnostics in debugfs.
2247 * They're called even less than the "set direction" calls.
2249 static int gpiod_request_commit(struct gpio_desc *desc, const char *label)
2251 unsigned int offset;
2254 CLASS(gpio_chip_guard, guard)(desc);
2258 if (test_and_set_bit(FLAG_REQUESTED, &desc->flags))
2261 /* NOTE: gpio_request() can be called in early boot,
2262 * before IRQs are enabled, for non-sleeping (SOC) GPIOs.
2265 if (guard.gc->request) {
2266 offset = gpio_chip_hwgpio(desc);
2267 if (gpiochip_line_is_valid(guard.gc, offset))
2268 ret = guard.gc->request(guard.gc, offset);
2275 if (guard.gc->get_direction)
2276 gpiod_get_direction(desc);
2278 ret = desc_set_label(desc, label ? : "?");
2285 clear_bit(FLAG_REQUESTED, &desc->flags);
2290 * This descriptor validation needs to be inserted verbatim into each
2291 * function taking a descriptor, so we need to use a preprocessor
2292 * macro to avoid endless duplication. If the desc is NULL it is an
2293 * optional GPIO and calls should just bail out.
2295 static int validate_desc(const struct gpio_desc *desc, const char *func)
2301 pr_warn("%s: invalid GPIO (errorpointer)\n", func);
2302 return PTR_ERR(desc);
2308 #define VALIDATE_DESC(desc) do { \
2309 int __valid = validate_desc(desc, __func__); \
2314 #define VALIDATE_DESC_VOID(desc) do { \
2315 int __valid = validate_desc(desc, __func__); \
2320 int gpiod_request(struct gpio_desc *desc, const char *label)
2322 int ret = -EPROBE_DEFER;
2324 VALIDATE_DESC(desc);
2326 if (try_module_get(desc->gdev->owner)) {
2327 ret = gpiod_request_commit(desc, label);
2329 module_put(desc->gdev->owner);
2331 gpio_device_get(desc->gdev);
2335 gpiod_dbg(desc, "%s: status %d\n", __func__, ret);
2340 static void gpiod_free_commit(struct gpio_desc *desc)
2342 unsigned long flags;
2346 CLASS(gpio_chip_guard, guard)(desc);
2348 flags = READ_ONCE(desc->flags);
2350 if (guard.gc && test_bit(FLAG_REQUESTED, &flags)) {
2352 guard.gc->free(guard.gc, gpio_chip_hwgpio(desc));
2354 clear_bit(FLAG_ACTIVE_LOW, &flags);
2355 clear_bit(FLAG_REQUESTED, &flags);
2356 clear_bit(FLAG_OPEN_DRAIN, &flags);
2357 clear_bit(FLAG_OPEN_SOURCE, &flags);
2358 clear_bit(FLAG_PULL_UP, &flags);
2359 clear_bit(FLAG_PULL_DOWN, &flags);
2360 clear_bit(FLAG_BIAS_DISABLE, &flags);
2361 clear_bit(FLAG_EDGE_RISING, &flags);
2362 clear_bit(FLAG_EDGE_FALLING, &flags);
2363 clear_bit(FLAG_IS_HOGGED, &flags);
2364 #ifdef CONFIG_OF_DYNAMIC
2365 WRITE_ONCE(desc->hog, NULL);
2367 desc_set_label(desc, NULL);
2368 WRITE_ONCE(desc->flags, flags);
2370 gpiod_line_state_notify(desc, GPIOLINE_CHANGED_RELEASED);
2374 void gpiod_free(struct gpio_desc *desc)
2376 VALIDATE_DESC_VOID(desc);
2378 gpiod_free_commit(desc);
2379 module_put(desc->gdev->owner);
2380 gpio_device_put(desc->gdev);
2384 * gpiochip_dup_line_label - Get a copy of the consumer label.
2385 * @gc: GPIO chip controlling this line.
2386 * @offset: Hardware offset of the line.
2389 * Pointer to a copy of the consumer label if the line is requested or NULL
2390 * if it's not. If a valid pointer was returned, it must be freed using
2391 * kfree(). In case of a memory allocation error, the function returns %ENOMEM.
2393 * Must not be called from atomic context.
2395 char *gpiochip_dup_line_label(struct gpio_chip *gc, unsigned int offset)
2397 struct gpio_desc *desc;
2400 desc = gpiochip_get_desc(gc, offset);
2404 if (!test_bit(FLAG_REQUESTED, &desc->flags))
2407 guard(srcu)(&desc->gdev->desc_srcu);
2409 label = kstrdup(gpiod_get_label(desc), GFP_KERNEL);
2411 return ERR_PTR(-ENOMEM);
2415 EXPORT_SYMBOL_GPL(gpiochip_dup_line_label);
2417 static inline const char *function_name_or_default(const char *con_id)
2419 return con_id ?: "(default)";
2423 * gpiochip_request_own_desc - Allow GPIO chip to request its own descriptor
2425 * @hwnum: hardware number of the GPIO for which to request the descriptor
2426 * @label: label for the GPIO
2427 * @lflags: lookup flags for this GPIO or 0 if default, this can be used to
2428 * specify things like line inversion semantics with the machine flags
2429 * such as GPIO_OUT_LOW
2430 * @dflags: descriptor request flags for this GPIO or 0 if default, this
2431 * can be used to specify consumer semantics such as open drain
2433 * Function allows GPIO chip drivers to request and use their own GPIO
2434 * descriptors via gpiolib API. Difference to gpiod_request() is that this
2435 * function will not increase reference count of the GPIO chip module. This
2436 * allows the GPIO chip module to be unloaded as needed (we assume that the
2437 * GPIO chip driver handles freeing the GPIOs it has requested).
2440 * A pointer to the GPIO descriptor, or an ERR_PTR()-encoded negative error
2443 struct gpio_desc *gpiochip_request_own_desc(struct gpio_chip *gc,
2446 enum gpio_lookup_flags lflags,
2447 enum gpiod_flags dflags)
2449 struct gpio_desc *desc = gpiochip_get_desc(gc, hwnum);
2450 const char *name = function_name_or_default(label);
2454 chip_err(gc, "failed to get GPIO %s descriptor\n", name);
2458 ret = gpiod_request_commit(desc, label);
2460 return ERR_PTR(ret);
2462 ret = gpiod_configure_flags(desc, label, lflags, dflags);
2464 gpiod_free_commit(desc);
2465 chip_err(gc, "setup of own GPIO %s failed\n", name);
2466 return ERR_PTR(ret);
2471 EXPORT_SYMBOL_GPL(gpiochip_request_own_desc);
2474 * gpiochip_free_own_desc - Free GPIO requested by the chip driver
2475 * @desc: GPIO descriptor to free
2477 * Function frees the given GPIO requested previously with
2478 * gpiochip_request_own_desc().
2480 void gpiochip_free_own_desc(struct gpio_desc *desc)
2483 gpiod_free_commit(desc);
2485 EXPORT_SYMBOL_GPL(gpiochip_free_own_desc);
2488 * Drivers MUST set GPIO direction before making get/set calls. In
2489 * some cases this is done in early boot, before IRQs are enabled.
2491 * As a rule these aren't called more than once (except for drivers
2492 * using the open-drain emulation idiom) so these are natural places
2493 * to accumulate extra debugging checks. Note that we can't (yet)
2494 * rely on gpio_request() having been called beforehand.
2497 static int gpio_do_set_config(struct gpio_chip *gc, unsigned int offset,
2498 unsigned long config)
2500 if (!gc->set_config)
2503 return gc->set_config(gc, offset, config);
2506 static int gpio_set_config_with_argument(struct gpio_desc *desc,
2507 enum pin_config_param mode,
2510 unsigned long config;
2512 CLASS(gpio_chip_guard, guard)(desc);
2516 config = pinconf_to_config_packed(mode, argument);
2517 return gpio_do_set_config(guard.gc, gpio_chip_hwgpio(desc), config);
2520 static int gpio_set_config_with_argument_optional(struct gpio_desc *desc,
2521 enum pin_config_param mode,
2524 struct device *dev = &desc->gdev->dev;
2525 int gpio = gpio_chip_hwgpio(desc);
2528 ret = gpio_set_config_with_argument(desc, mode, argument);
2529 if (ret != -ENOTSUPP)
2533 case PIN_CONFIG_PERSIST_STATE:
2534 dev_dbg(dev, "Persistence not supported for GPIO %d\n", gpio);
2543 static int gpio_set_config(struct gpio_desc *desc, enum pin_config_param mode)
2545 return gpio_set_config_with_argument(desc, mode, 0);
2548 static int gpio_set_bias(struct gpio_desc *desc)
2550 enum pin_config_param bias;
2551 unsigned long flags;
2554 flags = READ_ONCE(desc->flags);
2556 if (test_bit(FLAG_BIAS_DISABLE, &flags))
2557 bias = PIN_CONFIG_BIAS_DISABLE;
2558 else if (test_bit(FLAG_PULL_UP, &flags))
2559 bias = PIN_CONFIG_BIAS_PULL_UP;
2560 else if (test_bit(FLAG_PULL_DOWN, &flags))
2561 bias = PIN_CONFIG_BIAS_PULL_DOWN;
2566 case PIN_CONFIG_BIAS_PULL_DOWN:
2567 case PIN_CONFIG_BIAS_PULL_UP:
2576 return gpio_set_config_with_argument_optional(desc, bias, arg);
2580 * gpio_set_debounce_timeout() - Set debounce timeout
2581 * @desc: GPIO descriptor to set the debounce timeout
2582 * @debounce: Debounce timeout in microseconds
2584 * The function calls the certain GPIO driver to set debounce timeout
2587 * Returns 0 on success, or negative error code otherwise.
2589 int gpio_set_debounce_timeout(struct gpio_desc *desc, unsigned int debounce)
2591 return gpio_set_config_with_argument_optional(desc,
2592 PIN_CONFIG_INPUT_DEBOUNCE,
2597 * gpiod_direction_input - set the GPIO direction to input
2598 * @desc: GPIO to set to input
2600 * Set the direction of the passed GPIO to input, such as gpiod_get_value() can
2601 * be called safely on it.
2603 * Return 0 in case of success, else an error code.
2605 int gpiod_direction_input(struct gpio_desc *desc)
2609 VALIDATE_DESC(desc);
2611 CLASS(gpio_chip_guard, guard)(desc);
2616 * It is legal to have no .get() and .direction_input() specified if
2617 * the chip is output-only, but you can't specify .direction_input()
2618 * and not support the .get() operation, that doesn't make sense.
2620 if (!guard.gc->get && guard.gc->direction_input) {
2622 "%s: missing get() but have direction_input()\n",
2628 * If we have a .direction_input() callback, things are simple,
2629 * just call it. Else we are some input-only chip so try to check the
2630 * direction (if .get_direction() is supported) else we silently
2631 * assume we are in input mode after this.
2633 if (guard.gc->direction_input) {
2634 ret = guard.gc->direction_input(guard.gc,
2635 gpio_chip_hwgpio(desc));
2636 } else if (guard.gc->get_direction &&
2637 (guard.gc->get_direction(guard.gc,
2638 gpio_chip_hwgpio(desc)) != 1)) {
2640 "%s: missing direction_input() operation and line is output\n",
2645 clear_bit(FLAG_IS_OUT, &desc->flags);
2646 ret = gpio_set_bias(desc);
2649 trace_gpio_direction(desc_to_gpio(desc), 1, ret);
2653 EXPORT_SYMBOL_GPL(gpiod_direction_input);
2655 static int gpiod_direction_output_raw_commit(struct gpio_desc *desc, int value)
2657 int val = !!value, ret = 0;
2659 CLASS(gpio_chip_guard, guard)(desc);
2664 * It's OK not to specify .direction_output() if the gpiochip is
2665 * output-only, but if there is then not even a .set() operation it
2666 * is pretty tricky to drive the output line.
2668 if (!guard.gc->set && !guard.gc->direction_output) {
2670 "%s: missing set() and direction_output() operations\n",
2675 if (guard.gc->direction_output) {
2676 ret = guard.gc->direction_output(guard.gc,
2677 gpio_chip_hwgpio(desc), val);
2679 /* Check that we are in output mode if we can */
2680 if (guard.gc->get_direction &&
2681 guard.gc->get_direction(guard.gc, gpio_chip_hwgpio(desc))) {
2683 "%s: missing direction_output() operation\n",
2688 * If we can't actively set the direction, we are some
2689 * output-only chip, so just drive the output as desired.
2691 guard.gc->set(guard.gc, gpio_chip_hwgpio(desc), val);
2695 set_bit(FLAG_IS_OUT, &desc->flags);
2696 trace_gpio_value(desc_to_gpio(desc), 0, val);
2697 trace_gpio_direction(desc_to_gpio(desc), 0, ret);
2702 * gpiod_direction_output_raw - set the GPIO direction to output
2703 * @desc: GPIO to set to output
2704 * @value: initial output value of the GPIO
2706 * Set the direction of the passed GPIO to output, such as gpiod_set_value() can
2707 * be called safely on it. The initial value of the output must be specified
2708 * as raw value on the physical line without regard for the ACTIVE_LOW status.
2710 * Return 0 in case of success, else an error code.
2712 int gpiod_direction_output_raw(struct gpio_desc *desc, int value)
2714 VALIDATE_DESC(desc);
2715 return gpiod_direction_output_raw_commit(desc, value);
2717 EXPORT_SYMBOL_GPL(gpiod_direction_output_raw);
2720 * gpiod_direction_output - set the GPIO direction to output
2721 * @desc: GPIO to set to output
2722 * @value: initial output value of the GPIO
2724 * Set the direction of the passed GPIO to output, such as gpiod_set_value() can
2725 * be called safely on it. The initial value of the output must be specified
2726 * as the logical value of the GPIO, i.e. taking its ACTIVE_LOW status into
2729 * Return 0 in case of success, else an error code.
2731 int gpiod_direction_output(struct gpio_desc *desc, int value)
2733 unsigned long flags;
2736 VALIDATE_DESC(desc);
2738 flags = READ_ONCE(desc->flags);
2740 if (test_bit(FLAG_ACTIVE_LOW, &flags))
2745 /* GPIOs used for enabled IRQs shall not be set as output */
2746 if (test_bit(FLAG_USED_AS_IRQ, &flags) &&
2747 test_bit(FLAG_IRQ_IS_ENABLED, &flags)) {
2749 "%s: tried to set a GPIO tied to an IRQ as output\n",
2754 if (test_bit(FLAG_OPEN_DRAIN, &flags)) {
2755 /* First see if we can enable open drain in hardware */
2756 ret = gpio_set_config(desc, PIN_CONFIG_DRIVE_OPEN_DRAIN);
2758 goto set_output_value;
2759 /* Emulate open drain by not actively driving the line high */
2761 ret = gpiod_direction_input(desc);
2762 goto set_output_flag;
2764 } else if (test_bit(FLAG_OPEN_SOURCE, &flags)) {
2765 ret = gpio_set_config(desc, PIN_CONFIG_DRIVE_OPEN_SOURCE);
2767 goto set_output_value;
2768 /* Emulate open source by not actively driving the line low */
2770 ret = gpiod_direction_input(desc);
2771 goto set_output_flag;
2774 gpio_set_config(desc, PIN_CONFIG_DRIVE_PUSH_PULL);
2778 ret = gpio_set_bias(desc);
2781 return gpiod_direction_output_raw_commit(desc, value);
2785 * When emulating open-source or open-drain functionalities by not
2786 * actively driving the line (setting mode to input) we still need to
2787 * set the IS_OUT flag or otherwise we won't be able to set the line
2791 set_bit(FLAG_IS_OUT, &desc->flags);
2794 EXPORT_SYMBOL_GPL(gpiod_direction_output);
2797 * gpiod_enable_hw_timestamp_ns - Enable hardware timestamp in nanoseconds.
2799 * @desc: GPIO to enable.
2800 * @flags: Flags related to GPIO edge.
2802 * Return 0 in case of success, else negative error code.
2804 int gpiod_enable_hw_timestamp_ns(struct gpio_desc *desc, unsigned long flags)
2808 VALIDATE_DESC(desc);
2810 CLASS(gpio_chip_guard, guard)(desc);
2814 if (!guard.gc->en_hw_timestamp) {
2815 gpiod_warn(desc, "%s: hw ts not supported\n", __func__);
2819 ret = guard.gc->en_hw_timestamp(guard.gc,
2820 gpio_chip_hwgpio(desc), flags);
2822 gpiod_warn(desc, "%s: hw ts request failed\n", __func__);
2826 EXPORT_SYMBOL_GPL(gpiod_enable_hw_timestamp_ns);
2829 * gpiod_disable_hw_timestamp_ns - Disable hardware timestamp.
2831 * @desc: GPIO to disable.
2832 * @flags: Flags related to GPIO edge, same value as used during enable call.
2834 * Return 0 in case of success, else negative error code.
2836 int gpiod_disable_hw_timestamp_ns(struct gpio_desc *desc, unsigned long flags)
2840 VALIDATE_DESC(desc);
2842 CLASS(gpio_chip_guard, guard)(desc);
2846 if (!guard.gc->dis_hw_timestamp) {
2847 gpiod_warn(desc, "%s: hw ts not supported\n", __func__);
2851 ret = guard.gc->dis_hw_timestamp(guard.gc, gpio_chip_hwgpio(desc),
2854 gpiod_warn(desc, "%s: hw ts release failed\n", __func__);
2858 EXPORT_SYMBOL_GPL(gpiod_disable_hw_timestamp_ns);
2861 * gpiod_set_config - sets @config for a GPIO
2862 * @desc: descriptor of the GPIO for which to set the configuration
2863 * @config: Same packed config format as generic pinconf
2866 * 0 on success, %-ENOTSUPP if the controller doesn't support setting the
2869 int gpiod_set_config(struct gpio_desc *desc, unsigned long config)
2871 VALIDATE_DESC(desc);
2873 CLASS(gpio_chip_guard, guard)(desc);
2877 return gpio_do_set_config(guard.gc, gpio_chip_hwgpio(desc), config);
2879 EXPORT_SYMBOL_GPL(gpiod_set_config);
2882 * gpiod_set_debounce - sets @debounce time for a GPIO
2883 * @desc: descriptor of the GPIO for which to set debounce time
2884 * @debounce: debounce time in microseconds
2887 * 0 on success, %-ENOTSUPP if the controller doesn't support setting the
2890 int gpiod_set_debounce(struct gpio_desc *desc, unsigned int debounce)
2892 unsigned long config;
2894 config = pinconf_to_config_packed(PIN_CONFIG_INPUT_DEBOUNCE, debounce);
2895 return gpiod_set_config(desc, config);
2897 EXPORT_SYMBOL_GPL(gpiod_set_debounce);
2900 * gpiod_set_transitory - Lose or retain GPIO state on suspend or reset
2901 * @desc: descriptor of the GPIO for which to configure persistence
2902 * @transitory: True to lose state on suspend or reset, false for persistence
2905 * 0 on success, otherwise a negative error code.
2907 int gpiod_set_transitory(struct gpio_desc *desc, bool transitory)
2909 VALIDATE_DESC(desc);
2911 * Handle FLAG_TRANSITORY first, enabling queries to gpiolib for
2912 * persistence state.
2914 assign_bit(FLAG_TRANSITORY, &desc->flags, transitory);
2916 /* If the driver supports it, set the persistence state now */
2917 return gpio_set_config_with_argument_optional(desc,
2918 PIN_CONFIG_PERSIST_STATE,
2923 * gpiod_is_active_low - test whether a GPIO is active-low or not
2924 * @desc: the gpio descriptor to test
2926 * Returns 1 if the GPIO is active-low, 0 otherwise.
2928 int gpiod_is_active_low(const struct gpio_desc *desc)
2930 VALIDATE_DESC(desc);
2931 return test_bit(FLAG_ACTIVE_LOW, &desc->flags);
2933 EXPORT_SYMBOL_GPL(gpiod_is_active_low);
2936 * gpiod_toggle_active_low - toggle whether a GPIO is active-low or not
2937 * @desc: the gpio descriptor to change
2939 void gpiod_toggle_active_low(struct gpio_desc *desc)
2941 VALIDATE_DESC_VOID(desc);
2942 change_bit(FLAG_ACTIVE_LOW, &desc->flags);
2944 EXPORT_SYMBOL_GPL(gpiod_toggle_active_low);
2946 static int gpio_chip_get_value(struct gpio_chip *gc, const struct gpio_desc *desc)
2948 return gc->get ? gc->get(gc, gpio_chip_hwgpio(desc)) : -EIO;
2951 /* I/O calls are only valid after configuration completed; the relevant
2952 * "is this a valid GPIO" error checks should already have been done.
2954 * "Get" operations are often inlinable as reading a pin value register,
2955 * and masking the relevant bit in that register.
2957 * When "set" operations are inlinable, they involve writing that mask to
2958 * one register to set a low value, or a different register to set it high.
2959 * Otherwise locking is needed, so there may be little value to inlining.
2961 *------------------------------------------------------------------------
2963 * IMPORTANT!!! The hot paths -- get/set value -- assume that callers
2964 * have requested the GPIO. That can include implicit requesting by
2965 * a direction setting call. Marking a gpio as requested locks its chip
2966 * in memory, guaranteeing that these table lookups need no more locking
2967 * and that gpiochip_remove() will fail.
2969 * REVISIT when debugging, consider adding some instrumentation to ensure
2970 * that the GPIO was actually requested.
2973 static int gpiod_get_raw_value_commit(const struct gpio_desc *desc)
2975 struct gpio_device *gdev;
2976 struct gpio_chip *gc;
2979 /* FIXME Unable to use gpio_chip_guard due to const desc. */
2982 guard(srcu)(&gdev->srcu);
2984 gc = srcu_dereference(gdev->chip, &gdev->srcu);
2988 value = gpio_chip_get_value(gc, desc);
2989 value = value < 0 ? value : !!value;
2990 trace_gpio_value(desc_to_gpio(desc), 1, value);
2994 static int gpio_chip_get_multiple(struct gpio_chip *gc,
2995 unsigned long *mask, unsigned long *bits)
2997 if (gc->get_multiple)
2998 return gc->get_multiple(gc, mask, bits);
3002 for_each_set_bit(i, mask, gc->ngpio) {
3003 value = gc->get(gc, i);
3006 __assign_bit(i, bits, value);
3013 /* The 'other' chip must be protected with its GPIO device's SRCU. */
3014 static bool gpio_device_chip_cmp(struct gpio_device *gdev, struct gpio_chip *gc)
3016 guard(srcu)(&gdev->srcu);
3018 return gc == srcu_dereference(gdev->chip, &gdev->srcu);
3021 int gpiod_get_array_value_complex(bool raw, bool can_sleep,
3022 unsigned int array_size,
3023 struct gpio_desc **desc_array,
3024 struct gpio_array *array_info,
3025 unsigned long *value_bitmap)
3030 * Validate array_info against desc_array and its size.
3031 * It should immediately follow desc_array if both
3032 * have been obtained from the same gpiod_get_array() call.
3034 if (array_info && array_info->desc == desc_array &&
3035 array_size <= array_info->size &&
3036 (void *)array_info == desc_array + array_info->size) {
3038 WARN_ON(array_info->chip->can_sleep);
3040 ret = gpio_chip_get_multiple(array_info->chip,
3041 array_info->get_mask,
3046 if (!raw && !bitmap_empty(array_info->invert_mask, array_size))
3047 bitmap_xor(value_bitmap, value_bitmap,
3048 array_info->invert_mask, array_size);
3050 i = find_first_zero_bit(array_info->get_mask, array_size);
3051 if (i == array_size)
3057 while (i < array_size) {
3058 DECLARE_BITMAP(fastpath_mask, FASTPATH_NGPIO);
3059 DECLARE_BITMAP(fastpath_bits, FASTPATH_NGPIO);
3060 unsigned long *mask, *bits;
3063 CLASS(gpio_chip_guard, guard)(desc_array[i]);
3067 if (likely(guard.gc->ngpio <= FASTPATH_NGPIO)) {
3068 mask = fastpath_mask;
3069 bits = fastpath_bits;
3071 gfp_t flags = can_sleep ? GFP_KERNEL : GFP_ATOMIC;
3073 mask = bitmap_alloc(guard.gc->ngpio, flags);
3077 bits = bitmap_alloc(guard.gc->ngpio, flags);
3084 bitmap_zero(mask, guard.gc->ngpio);
3087 WARN_ON(guard.gc->can_sleep);
3089 /* collect all inputs belonging to the same chip */
3092 const struct gpio_desc *desc = desc_array[i];
3093 int hwgpio = gpio_chip_hwgpio(desc);
3095 __set_bit(hwgpio, mask);
3099 i = find_next_zero_bit(array_info->get_mask,
3101 } while ((i < array_size) &&
3102 gpio_device_chip_cmp(desc_array[i]->gdev, guard.gc));
3104 ret = gpio_chip_get_multiple(guard.gc, mask, bits);
3106 if (mask != fastpath_mask)
3108 if (bits != fastpath_bits)
3113 for (j = first; j < i; ) {
3114 const struct gpio_desc *desc = desc_array[j];
3115 int hwgpio = gpio_chip_hwgpio(desc);
3116 int value = test_bit(hwgpio, bits);
3118 if (!raw && test_bit(FLAG_ACTIVE_LOW, &desc->flags))
3120 __assign_bit(j, value_bitmap, value);
3121 trace_gpio_value(desc_to_gpio(desc), 1, value);
3125 j = find_next_zero_bit(array_info->get_mask, i,
3129 if (mask != fastpath_mask)
3131 if (bits != fastpath_bits)
3138 * gpiod_get_raw_value() - return a gpio's raw value
3139 * @desc: gpio whose value will be returned
3141 * Return the GPIO's raw value, i.e. the value of the physical line disregarding
3142 * its ACTIVE_LOW status, or negative errno on failure.
3144 * This function can be called from contexts where we cannot sleep, and will
3145 * complain if the GPIO chip functions potentially sleep.
3147 int gpiod_get_raw_value(const struct gpio_desc *desc)
3149 VALIDATE_DESC(desc);
3150 /* Should be using gpiod_get_raw_value_cansleep() */
3151 WARN_ON(desc->gdev->can_sleep);
3152 return gpiod_get_raw_value_commit(desc);
3154 EXPORT_SYMBOL_GPL(gpiod_get_raw_value);
3157 * gpiod_get_value() - return a gpio's value
3158 * @desc: gpio whose value will be returned
3160 * Return the GPIO's logical value, i.e. taking the ACTIVE_LOW status into
3161 * account, or negative errno on failure.
3163 * This function can be called from contexts where we cannot sleep, and will
3164 * complain if the GPIO chip functions potentially sleep.
3166 int gpiod_get_value(const struct gpio_desc *desc)
3170 VALIDATE_DESC(desc);
3171 /* Should be using gpiod_get_value_cansleep() */
3172 WARN_ON(desc->gdev->can_sleep);
3174 value = gpiod_get_raw_value_commit(desc);
3178 if (test_bit(FLAG_ACTIVE_LOW, &desc->flags))
3183 EXPORT_SYMBOL_GPL(gpiod_get_value);
3186 * gpiod_get_raw_array_value() - read raw values from an array of GPIOs
3187 * @array_size: number of elements in the descriptor array / value bitmap
3188 * @desc_array: array of GPIO descriptors whose values will be read
3189 * @array_info: information on applicability of fast bitmap processing path
3190 * @value_bitmap: bitmap to store the read values
3192 * Read the raw values of the GPIOs, i.e. the values of the physical lines
3193 * without regard for their ACTIVE_LOW status. Return 0 in case of success,
3194 * else an error code.
3196 * This function can be called from contexts where we cannot sleep,
3197 * and it will complain if the GPIO chip functions potentially sleep.
3199 int gpiod_get_raw_array_value(unsigned int array_size,
3200 struct gpio_desc **desc_array,
3201 struct gpio_array *array_info,
3202 unsigned long *value_bitmap)
3206 return gpiod_get_array_value_complex(true, false, array_size,
3207 desc_array, array_info,
3210 EXPORT_SYMBOL_GPL(gpiod_get_raw_array_value);
3213 * gpiod_get_array_value() - read values from an array of GPIOs
3214 * @array_size: number of elements in the descriptor array / value bitmap
3215 * @desc_array: array of GPIO descriptors whose values will be read
3216 * @array_info: information on applicability of fast bitmap processing path
3217 * @value_bitmap: bitmap to store the read values
3219 * Read the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status
3220 * into account. Return 0 in case of success, else an error code.
3222 * This function can be called from contexts where we cannot sleep,
3223 * and it will complain if the GPIO chip functions potentially sleep.
3225 int gpiod_get_array_value(unsigned int array_size,
3226 struct gpio_desc **desc_array,
3227 struct gpio_array *array_info,
3228 unsigned long *value_bitmap)
3232 return gpiod_get_array_value_complex(false, false, array_size,
3233 desc_array, array_info,
3236 EXPORT_SYMBOL_GPL(gpiod_get_array_value);
3239 * gpio_set_open_drain_value_commit() - Set the open drain gpio's value.
3240 * @desc: gpio descriptor whose state need to be set.
3241 * @value: Non-zero for setting it HIGH otherwise it will set to LOW.
3243 static void gpio_set_open_drain_value_commit(struct gpio_desc *desc, bool value)
3245 int ret = 0, offset = gpio_chip_hwgpio(desc);
3247 CLASS(gpio_chip_guard, guard)(desc);
3252 ret = guard.gc->direction_input(guard.gc, offset);
3254 ret = guard.gc->direction_output(guard.gc, offset, 0);
3256 set_bit(FLAG_IS_OUT, &desc->flags);
3258 trace_gpio_direction(desc_to_gpio(desc), value, ret);
3261 "%s: Error in set_value for open drain err %d\n",
3266 * _gpio_set_open_source_value() - Set the open source gpio's value.
3267 * @desc: gpio descriptor whose state need to be set.
3268 * @value: Non-zero for setting it HIGH otherwise it will set to LOW.
3270 static void gpio_set_open_source_value_commit(struct gpio_desc *desc, bool value)
3272 int ret = 0, offset = gpio_chip_hwgpio(desc);
3274 CLASS(gpio_chip_guard, guard)(desc);
3279 ret = guard.gc->direction_output(guard.gc, offset, 1);
3281 set_bit(FLAG_IS_OUT, &desc->flags);
3283 ret = guard.gc->direction_input(guard.gc, offset);
3285 trace_gpio_direction(desc_to_gpio(desc), !value, ret);
3288 "%s: Error in set_value for open source err %d\n",
3292 static void gpiod_set_raw_value_commit(struct gpio_desc *desc, bool value)
3294 CLASS(gpio_chip_guard, guard)(desc);
3298 trace_gpio_value(desc_to_gpio(desc), 0, value);
3299 guard.gc->set(guard.gc, gpio_chip_hwgpio(desc), value);
3303 * set multiple outputs on the same chip;
3304 * use the chip's set_multiple function if available;
3305 * otherwise set the outputs sequentially;
3306 * @chip: the GPIO chip we operate on
3307 * @mask: bit mask array; one bit per output; BITS_PER_LONG bits per word
3308 * defines which outputs are to be changed
3309 * @bits: bit value array; one bit per output; BITS_PER_LONG bits per word
3310 * defines the values the outputs specified by mask are to be set to
3312 static void gpio_chip_set_multiple(struct gpio_chip *gc,
3313 unsigned long *mask, unsigned long *bits)
3315 if (gc->set_multiple) {
3316 gc->set_multiple(gc, mask, bits);
3320 /* set outputs if the corresponding mask bit is set */
3321 for_each_set_bit(i, mask, gc->ngpio)
3322 gc->set(gc, i, test_bit(i, bits));
3326 int gpiod_set_array_value_complex(bool raw, bool can_sleep,
3327 unsigned int array_size,
3328 struct gpio_desc **desc_array,
3329 struct gpio_array *array_info,
3330 unsigned long *value_bitmap)
3335 * Validate array_info against desc_array and its size.
3336 * It should immediately follow desc_array if both
3337 * have been obtained from the same gpiod_get_array() call.
3339 if (array_info && array_info->desc == desc_array &&
3340 array_size <= array_info->size &&
3341 (void *)array_info == desc_array + array_info->size) {
3343 WARN_ON(array_info->chip->can_sleep);
3345 if (!raw && !bitmap_empty(array_info->invert_mask, array_size))
3346 bitmap_xor(value_bitmap, value_bitmap,
3347 array_info->invert_mask, array_size);
3349 gpio_chip_set_multiple(array_info->chip, array_info->set_mask,
3352 i = find_first_zero_bit(array_info->set_mask, array_size);
3353 if (i == array_size)
3359 while (i < array_size) {
3360 DECLARE_BITMAP(fastpath_mask, FASTPATH_NGPIO);
3361 DECLARE_BITMAP(fastpath_bits, FASTPATH_NGPIO);
3362 unsigned long *mask, *bits;
3365 CLASS(gpio_chip_guard, guard)(desc_array[i]);
3369 if (likely(guard.gc->ngpio <= FASTPATH_NGPIO)) {
3370 mask = fastpath_mask;
3371 bits = fastpath_bits;
3373 gfp_t flags = can_sleep ? GFP_KERNEL : GFP_ATOMIC;
3375 mask = bitmap_alloc(guard.gc->ngpio, flags);
3379 bits = bitmap_alloc(guard.gc->ngpio, flags);
3386 bitmap_zero(mask, guard.gc->ngpio);
3389 WARN_ON(guard.gc->can_sleep);
3392 struct gpio_desc *desc = desc_array[i];
3393 int hwgpio = gpio_chip_hwgpio(desc);
3394 int value = test_bit(i, value_bitmap);
3397 * Pins applicable for fast input but not for
3398 * fast output processing may have been already
3399 * inverted inside the fast path, skip them.
3401 if (!raw && !(array_info &&
3402 test_bit(i, array_info->invert_mask)) &&
3403 test_bit(FLAG_ACTIVE_LOW, &desc->flags))
3405 trace_gpio_value(desc_to_gpio(desc), 0, value);
3407 * collect all normal outputs belonging to the same chip
3408 * open drain and open source outputs are set individually
3410 if (test_bit(FLAG_OPEN_DRAIN, &desc->flags) && !raw) {
3411 gpio_set_open_drain_value_commit(desc, value);
3412 } else if (test_bit(FLAG_OPEN_SOURCE, &desc->flags) && !raw) {
3413 gpio_set_open_source_value_commit(desc, value);
3415 __set_bit(hwgpio, mask);
3416 __assign_bit(hwgpio, bits, value);
3422 i = find_next_zero_bit(array_info->set_mask,
3424 } while ((i < array_size) &&
3425 gpio_device_chip_cmp(desc_array[i]->gdev, guard.gc));
3426 /* push collected bits to outputs */
3428 gpio_chip_set_multiple(guard.gc, mask, bits);
3430 if (mask != fastpath_mask)
3432 if (bits != fastpath_bits)
3439 * gpiod_set_raw_value() - assign a gpio's raw value
3440 * @desc: gpio whose value will be assigned
3441 * @value: value to assign
3443 * Set the raw value of the GPIO, i.e. the value of its physical line without
3444 * regard for its ACTIVE_LOW status.
3446 * This function can be called from contexts where we cannot sleep, and will
3447 * complain if the GPIO chip functions potentially sleep.
3449 void gpiod_set_raw_value(struct gpio_desc *desc, int value)
3451 VALIDATE_DESC_VOID(desc);
3452 /* Should be using gpiod_set_raw_value_cansleep() */
3453 WARN_ON(desc->gdev->can_sleep);
3454 gpiod_set_raw_value_commit(desc, value);
3456 EXPORT_SYMBOL_GPL(gpiod_set_raw_value);
3459 * gpiod_set_value_nocheck() - set a GPIO line value without checking
3460 * @desc: the descriptor to set the value on
3461 * @value: value to set
3463 * This sets the value of a GPIO line backing a descriptor, applying
3464 * different semantic quirks like active low and open drain/source
3467 static void gpiod_set_value_nocheck(struct gpio_desc *desc, int value)
3469 if (test_bit(FLAG_ACTIVE_LOW, &desc->flags))
3471 if (test_bit(FLAG_OPEN_DRAIN, &desc->flags))
3472 gpio_set_open_drain_value_commit(desc, value);
3473 else if (test_bit(FLAG_OPEN_SOURCE, &desc->flags))
3474 gpio_set_open_source_value_commit(desc, value);
3476 gpiod_set_raw_value_commit(desc, value);
3480 * gpiod_set_value() - assign a gpio's value
3481 * @desc: gpio whose value will be assigned
3482 * @value: value to assign
3484 * Set the logical value of the GPIO, i.e. taking its ACTIVE_LOW,
3485 * OPEN_DRAIN and OPEN_SOURCE flags into account.
3487 * This function can be called from contexts where we cannot sleep, and will
3488 * complain if the GPIO chip functions potentially sleep.
3490 void gpiod_set_value(struct gpio_desc *desc, int value)
3492 VALIDATE_DESC_VOID(desc);
3493 /* Should be using gpiod_set_value_cansleep() */
3494 WARN_ON(desc->gdev->can_sleep);
3495 gpiod_set_value_nocheck(desc, value);
3497 EXPORT_SYMBOL_GPL(gpiod_set_value);
3500 * gpiod_set_raw_array_value() - assign values to an array of GPIOs
3501 * @array_size: number of elements in the descriptor array / value bitmap
3502 * @desc_array: array of GPIO descriptors whose values will be assigned
3503 * @array_info: information on applicability of fast bitmap processing path
3504 * @value_bitmap: bitmap of values to assign
3506 * Set the raw values of the GPIOs, i.e. the values of the physical lines
3507 * without regard for their ACTIVE_LOW status.
3509 * This function can be called from contexts where we cannot sleep, and will
3510 * complain if the GPIO chip functions potentially sleep.
3512 int gpiod_set_raw_array_value(unsigned int array_size,
3513 struct gpio_desc **desc_array,
3514 struct gpio_array *array_info,
3515 unsigned long *value_bitmap)
3519 return gpiod_set_array_value_complex(true, false, array_size,
3520 desc_array, array_info, value_bitmap);
3522 EXPORT_SYMBOL_GPL(gpiod_set_raw_array_value);
3525 * gpiod_set_array_value() - assign values to an array of GPIOs
3526 * @array_size: number of elements in the descriptor array / value bitmap
3527 * @desc_array: array of GPIO descriptors whose values will be assigned
3528 * @array_info: information on applicability of fast bitmap processing path
3529 * @value_bitmap: bitmap of values to assign
3531 * Set the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status
3534 * This function can be called from contexts where we cannot sleep, and will
3535 * complain if the GPIO chip functions potentially sleep.
3537 int gpiod_set_array_value(unsigned int array_size,
3538 struct gpio_desc **desc_array,
3539 struct gpio_array *array_info,
3540 unsigned long *value_bitmap)
3544 return gpiod_set_array_value_complex(false, false, array_size,
3545 desc_array, array_info,
3548 EXPORT_SYMBOL_GPL(gpiod_set_array_value);
3551 * gpiod_cansleep() - report whether gpio value access may sleep
3552 * @desc: gpio to check
3555 int gpiod_cansleep(const struct gpio_desc *desc)
3557 VALIDATE_DESC(desc);
3558 return desc->gdev->can_sleep;
3560 EXPORT_SYMBOL_GPL(gpiod_cansleep);
3563 * gpiod_set_consumer_name() - set the consumer name for the descriptor
3564 * @desc: gpio to set the consumer name on
3565 * @name: the new consumer name
3567 int gpiod_set_consumer_name(struct gpio_desc *desc, const char *name)
3569 VALIDATE_DESC(desc);
3571 return desc_set_label(desc, name);
3573 EXPORT_SYMBOL_GPL(gpiod_set_consumer_name);
3576 * gpiod_to_irq() - return the IRQ corresponding to a GPIO
3577 * @desc: gpio whose IRQ will be returned (already requested)
3579 * Return the IRQ corresponding to the passed GPIO, or an error code in case of
3582 int gpiod_to_irq(const struct gpio_desc *desc)
3584 struct gpio_device *gdev;
3585 struct gpio_chip *gc;
3589 * Cannot VALIDATE_DESC() here as gpiod_to_irq() consumer semantics
3590 * requires this function to not return zero on an invalid descriptor
3591 * but rather a negative error number.
3593 if (!desc || IS_ERR(desc))
3597 /* FIXME Cannot use gpio_chip_guard due to const desc. */
3598 guard(srcu)(&gdev->srcu);
3599 gc = srcu_dereference(gdev->chip, &gdev->srcu);
3603 offset = gpio_chip_hwgpio(desc);
3605 int retirq = gc->to_irq(gc, offset);
3607 /* Zero means NO_IRQ */
3613 #ifdef CONFIG_GPIOLIB_IRQCHIP
3616 * Avoid race condition with other code, which tries to lookup
3617 * an IRQ before the irqchip has been properly registered,
3618 * i.e. while gpiochip is still being brought up.
3620 return -EPROBE_DEFER;
3625 EXPORT_SYMBOL_GPL(gpiod_to_irq);
3628 * gpiochip_lock_as_irq() - lock a GPIO to be used as IRQ
3629 * @gc: the chip the GPIO to lock belongs to
3630 * @offset: the offset of the GPIO to lock as IRQ
3632 * This is used directly by GPIO drivers that want to lock down
3633 * a certain GPIO line to be used for IRQs.
3635 int gpiochip_lock_as_irq(struct gpio_chip *gc, unsigned int offset)
3637 struct gpio_desc *desc;
3639 desc = gpiochip_get_desc(gc, offset);
3641 return PTR_ERR(desc);
3644 * If it's fast: flush the direction setting if something changed
3647 if (!gc->can_sleep && gc->get_direction) {
3648 int dir = gpiod_get_direction(desc);
3651 chip_err(gc, "%s: cannot get GPIO direction\n",
3657 /* To be valid for IRQ the line needs to be input or open drain */
3658 if (test_bit(FLAG_IS_OUT, &desc->flags) &&
3659 !test_bit(FLAG_OPEN_DRAIN, &desc->flags)) {
3661 "%s: tried to flag a GPIO set as output for IRQ\n",
3666 set_bit(FLAG_USED_AS_IRQ, &desc->flags);
3667 set_bit(FLAG_IRQ_IS_ENABLED, &desc->flags);
3671 EXPORT_SYMBOL_GPL(gpiochip_lock_as_irq);
3674 * gpiochip_unlock_as_irq() - unlock a GPIO used as IRQ
3675 * @gc: the chip the GPIO to lock belongs to
3676 * @offset: the offset of the GPIO to lock as IRQ
3678 * This is used directly by GPIO drivers that want to indicate
3679 * that a certain GPIO is no longer used exclusively for IRQ.
3681 void gpiochip_unlock_as_irq(struct gpio_chip *gc, unsigned int offset)
3683 struct gpio_desc *desc;
3685 desc = gpiochip_get_desc(gc, offset);
3689 clear_bit(FLAG_USED_AS_IRQ, &desc->flags);
3690 clear_bit(FLAG_IRQ_IS_ENABLED, &desc->flags);
3692 EXPORT_SYMBOL_GPL(gpiochip_unlock_as_irq);
3694 void gpiochip_disable_irq(struct gpio_chip *gc, unsigned int offset)
3696 struct gpio_desc *desc = gpiochip_get_desc(gc, offset);
3698 if (!IS_ERR(desc) &&
3699 !WARN_ON(!test_bit(FLAG_USED_AS_IRQ, &desc->flags)))
3700 clear_bit(FLAG_IRQ_IS_ENABLED, &desc->flags);
3702 EXPORT_SYMBOL_GPL(gpiochip_disable_irq);
3704 void gpiochip_enable_irq(struct gpio_chip *gc, unsigned int offset)
3706 struct gpio_desc *desc = gpiochip_get_desc(gc, offset);
3708 if (!IS_ERR(desc) &&
3709 !WARN_ON(!test_bit(FLAG_USED_AS_IRQ, &desc->flags))) {
3711 * We must not be output when using IRQ UNLESS we are
3714 WARN_ON(test_bit(FLAG_IS_OUT, &desc->flags) &&
3715 !test_bit(FLAG_OPEN_DRAIN, &desc->flags));
3716 set_bit(FLAG_IRQ_IS_ENABLED, &desc->flags);
3719 EXPORT_SYMBOL_GPL(gpiochip_enable_irq);
3721 bool gpiochip_line_is_irq(struct gpio_chip *gc, unsigned int offset)
3723 if (offset >= gc->ngpio)
3726 return test_bit(FLAG_USED_AS_IRQ, &gc->gpiodev->descs[offset].flags);
3728 EXPORT_SYMBOL_GPL(gpiochip_line_is_irq);
3730 int gpiochip_reqres_irq(struct gpio_chip *gc, unsigned int offset)
3734 if (!try_module_get(gc->gpiodev->owner))
3737 ret = gpiochip_lock_as_irq(gc, offset);
3739 chip_err(gc, "unable to lock HW IRQ %u for IRQ\n", offset);
3740 module_put(gc->gpiodev->owner);
3745 EXPORT_SYMBOL_GPL(gpiochip_reqres_irq);
3747 void gpiochip_relres_irq(struct gpio_chip *gc, unsigned int offset)
3749 gpiochip_unlock_as_irq(gc, offset);
3750 module_put(gc->gpiodev->owner);
3752 EXPORT_SYMBOL_GPL(gpiochip_relres_irq);
3754 bool gpiochip_line_is_open_drain(struct gpio_chip *gc, unsigned int offset)
3756 if (offset >= gc->ngpio)
3759 return test_bit(FLAG_OPEN_DRAIN, &gc->gpiodev->descs[offset].flags);
3761 EXPORT_SYMBOL_GPL(gpiochip_line_is_open_drain);
3763 bool gpiochip_line_is_open_source(struct gpio_chip *gc, unsigned int offset)
3765 if (offset >= gc->ngpio)
3768 return test_bit(FLAG_OPEN_SOURCE, &gc->gpiodev->descs[offset].flags);
3770 EXPORT_SYMBOL_GPL(gpiochip_line_is_open_source);
3772 bool gpiochip_line_is_persistent(struct gpio_chip *gc, unsigned int offset)
3774 if (offset >= gc->ngpio)
3777 return !test_bit(FLAG_TRANSITORY, &gc->gpiodev->descs[offset].flags);
3779 EXPORT_SYMBOL_GPL(gpiochip_line_is_persistent);
3782 * gpiod_get_raw_value_cansleep() - return a gpio's raw value
3783 * @desc: gpio whose value will be returned
3785 * Return the GPIO's raw value, i.e. the value of the physical line disregarding
3786 * its ACTIVE_LOW status, or negative errno on failure.
3788 * This function is to be called from contexts that can sleep.
3790 int gpiod_get_raw_value_cansleep(const struct gpio_desc *desc)
3793 VALIDATE_DESC(desc);
3794 return gpiod_get_raw_value_commit(desc);
3796 EXPORT_SYMBOL_GPL(gpiod_get_raw_value_cansleep);
3799 * gpiod_get_value_cansleep() - return a gpio's value
3800 * @desc: gpio whose value will be returned
3802 * Return the GPIO's logical value, i.e. taking the ACTIVE_LOW status into
3803 * account, or negative errno on failure.
3805 * This function is to be called from contexts that can sleep.
3807 int gpiod_get_value_cansleep(const struct gpio_desc *desc)
3812 VALIDATE_DESC(desc);
3813 value = gpiod_get_raw_value_commit(desc);
3817 if (test_bit(FLAG_ACTIVE_LOW, &desc->flags))
3822 EXPORT_SYMBOL_GPL(gpiod_get_value_cansleep);
3825 * gpiod_get_raw_array_value_cansleep() - read raw values from an array of GPIOs
3826 * @array_size: number of elements in the descriptor array / value bitmap
3827 * @desc_array: array of GPIO descriptors whose values will be read
3828 * @array_info: information on applicability of fast bitmap processing path
3829 * @value_bitmap: bitmap to store the read values
3831 * Read the raw values of the GPIOs, i.e. the values of the physical lines
3832 * without regard for their ACTIVE_LOW status. Return 0 in case of success,
3833 * else an error code.
3835 * This function is to be called from contexts that can sleep.
3837 int gpiod_get_raw_array_value_cansleep(unsigned int array_size,
3838 struct gpio_desc **desc_array,
3839 struct gpio_array *array_info,
3840 unsigned long *value_bitmap)
3845 return gpiod_get_array_value_complex(true, true, array_size,
3846 desc_array, array_info,
3849 EXPORT_SYMBOL_GPL(gpiod_get_raw_array_value_cansleep);
3852 * gpiod_get_array_value_cansleep() - read values from an array of GPIOs
3853 * @array_size: number of elements in the descriptor array / value bitmap
3854 * @desc_array: array of GPIO descriptors whose values will be read
3855 * @array_info: information on applicability of fast bitmap processing path
3856 * @value_bitmap: bitmap to store the read values
3858 * Read the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status
3859 * into account. Return 0 in case of success, else an error code.
3861 * This function is to be called from contexts that can sleep.
3863 int gpiod_get_array_value_cansleep(unsigned int array_size,
3864 struct gpio_desc **desc_array,
3865 struct gpio_array *array_info,
3866 unsigned long *value_bitmap)
3871 return gpiod_get_array_value_complex(false, true, array_size,
3872 desc_array, array_info,
3875 EXPORT_SYMBOL_GPL(gpiod_get_array_value_cansleep);
3878 * gpiod_set_raw_value_cansleep() - assign a gpio's raw value
3879 * @desc: gpio whose value will be assigned
3880 * @value: value to assign
3882 * Set the raw value of the GPIO, i.e. the value of its physical line without
3883 * regard for its ACTIVE_LOW status.
3885 * This function is to be called from contexts that can sleep.
3887 void gpiod_set_raw_value_cansleep(struct gpio_desc *desc, int value)
3890 VALIDATE_DESC_VOID(desc);
3891 gpiod_set_raw_value_commit(desc, value);
3893 EXPORT_SYMBOL_GPL(gpiod_set_raw_value_cansleep);
3896 * gpiod_set_value_cansleep() - assign a gpio's value
3897 * @desc: gpio whose value will be assigned
3898 * @value: value to assign
3900 * Set the logical value of the GPIO, i.e. taking its ACTIVE_LOW status into
3903 * This function is to be called from contexts that can sleep.
3905 void gpiod_set_value_cansleep(struct gpio_desc *desc, int value)
3908 VALIDATE_DESC_VOID(desc);
3909 gpiod_set_value_nocheck(desc, value);
3911 EXPORT_SYMBOL_GPL(gpiod_set_value_cansleep);
3914 * gpiod_set_raw_array_value_cansleep() - assign values to an array of GPIOs
3915 * @array_size: number of elements in the descriptor array / value bitmap
3916 * @desc_array: array of GPIO descriptors whose values will be assigned
3917 * @array_info: information on applicability of fast bitmap processing path
3918 * @value_bitmap: bitmap of values to assign
3920 * Set the raw values of the GPIOs, i.e. the values of the physical lines
3921 * without regard for their ACTIVE_LOW status.
3923 * This function is to be called from contexts that can sleep.
3925 int gpiod_set_raw_array_value_cansleep(unsigned int array_size,
3926 struct gpio_desc **desc_array,
3927 struct gpio_array *array_info,
3928 unsigned long *value_bitmap)
3933 return gpiod_set_array_value_complex(true, true, array_size, desc_array,
3934 array_info, value_bitmap);
3936 EXPORT_SYMBOL_GPL(gpiod_set_raw_array_value_cansleep);
3939 * gpiod_add_lookup_tables() - register GPIO device consumers
3940 * @tables: list of tables of consumers to register
3941 * @n: number of tables in the list
3943 void gpiod_add_lookup_tables(struct gpiod_lookup_table **tables, size_t n)
3947 mutex_lock(&gpio_lookup_lock);
3949 for (i = 0; i < n; i++)
3950 list_add_tail(&tables[i]->list, &gpio_lookup_list);
3952 mutex_unlock(&gpio_lookup_lock);
3956 * gpiod_set_array_value_cansleep() - assign values to an array of GPIOs
3957 * @array_size: number of elements in the descriptor array / value bitmap
3958 * @desc_array: array of GPIO descriptors whose values will be assigned
3959 * @array_info: information on applicability of fast bitmap processing path
3960 * @value_bitmap: bitmap of values to assign
3962 * Set the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status
3965 * This function is to be called from contexts that can sleep.
3967 int gpiod_set_array_value_cansleep(unsigned int array_size,
3968 struct gpio_desc **desc_array,
3969 struct gpio_array *array_info,
3970 unsigned long *value_bitmap)
3975 return gpiod_set_array_value_complex(false, true, array_size,
3976 desc_array, array_info,
3979 EXPORT_SYMBOL_GPL(gpiod_set_array_value_cansleep);
3981 void gpiod_line_state_notify(struct gpio_desc *desc, unsigned long action)
3983 blocking_notifier_call_chain(&desc->gdev->line_state_notifier,
3988 * gpiod_add_lookup_table() - register GPIO device consumers
3989 * @table: table of consumers to register
3991 void gpiod_add_lookup_table(struct gpiod_lookup_table *table)
3993 gpiod_add_lookup_tables(&table, 1);
3995 EXPORT_SYMBOL_GPL(gpiod_add_lookup_table);
3998 * gpiod_remove_lookup_table() - unregister GPIO device consumers
3999 * @table: table of consumers to unregister
4001 void gpiod_remove_lookup_table(struct gpiod_lookup_table *table)
4003 /* Nothing to remove */
4007 mutex_lock(&gpio_lookup_lock);
4009 list_del(&table->list);
4011 mutex_unlock(&gpio_lookup_lock);
4013 EXPORT_SYMBOL_GPL(gpiod_remove_lookup_table);
4016 * gpiod_add_hogs() - register a set of GPIO hogs from machine code
4017 * @hogs: table of gpio hog entries with a zeroed sentinel at the end
4019 void gpiod_add_hogs(struct gpiod_hog *hogs)
4021 struct gpiod_hog *hog;
4023 mutex_lock(&gpio_machine_hogs_mutex);
4025 for (hog = &hogs[0]; hog->chip_label; hog++) {
4026 list_add_tail(&hog->list, &gpio_machine_hogs);
4029 * The chip may have been registered earlier, so check if it
4030 * exists and, if so, try to hog the line now.
4032 struct gpio_device *gdev __free(gpio_device_put) =
4033 gpio_device_find_by_label(hog->chip_label);
4035 gpiochip_machine_hog(gpio_device_get_chip(gdev), hog);
4038 mutex_unlock(&gpio_machine_hogs_mutex);
4040 EXPORT_SYMBOL_GPL(gpiod_add_hogs);
4042 void gpiod_remove_hogs(struct gpiod_hog *hogs)
4044 struct gpiod_hog *hog;
4046 mutex_lock(&gpio_machine_hogs_mutex);
4047 for (hog = &hogs[0]; hog->chip_label; hog++)
4048 list_del(&hog->list);
4049 mutex_unlock(&gpio_machine_hogs_mutex);
4051 EXPORT_SYMBOL_GPL(gpiod_remove_hogs);
4053 static struct gpiod_lookup_table *gpiod_find_lookup_table(struct device *dev)
4055 const char *dev_id = dev ? dev_name(dev) : NULL;
4056 struct gpiod_lookup_table *table;
4058 list_for_each_entry(table, &gpio_lookup_list, list) {
4059 if (table->dev_id && dev_id) {
4061 * Valid strings on both ends, must be identical to have
4064 if (!strcmp(table->dev_id, dev_id))
4068 * One of the pointers is NULL, so both must be to have
4071 if (dev_id == table->dev_id)
4079 static struct gpio_desc *gpiod_find(struct device *dev, const char *con_id,
4080 unsigned int idx, unsigned long *flags)
4082 struct gpio_desc *desc = ERR_PTR(-ENOENT);
4083 struct gpiod_lookup_table *table;
4084 struct gpiod_lookup *p;
4085 struct gpio_chip *gc;
4087 guard(mutex)(&gpio_lookup_lock);
4089 table = gpiod_find_lookup_table(dev);
4093 for (p = &table->table[0]; p->key; p++) {
4094 /* idx must always match exactly */
4098 /* If the lookup entry has a con_id, require exact match */
4099 if (p->con_id && (!con_id || strcmp(p->con_id, con_id)))
4102 if (p->chip_hwnum == U16_MAX) {
4103 desc = gpio_name_to_desc(p->key);
4109 dev_warn(dev, "cannot find GPIO line %s, deferring\n",
4111 return ERR_PTR(-EPROBE_DEFER);
4114 struct gpio_device *gdev __free(gpio_device_put) =
4115 gpio_device_find_by_label(p->key);
4118 * As the lookup table indicates a chip with
4119 * p->key should exist, assume it may
4120 * still appear later and let the interested
4121 * consumer be probed again or let the Deferred
4122 * Probe infrastructure handle the error.
4124 dev_warn(dev, "cannot find GPIO chip %s, deferring\n",
4126 return ERR_PTR(-EPROBE_DEFER);
4129 gc = gpio_device_get_chip(gdev);
4131 if (gc->ngpio <= p->chip_hwnum) {
4133 "requested GPIO %u (%u) is out of range [0..%u] for chip %s\n",
4134 idx, p->chip_hwnum, gc->ngpio - 1,
4136 return ERR_PTR(-EINVAL);
4139 desc = gpio_device_get_desc(gdev, p->chip_hwnum);
4148 static int platform_gpio_count(struct device *dev, const char *con_id)
4150 struct gpiod_lookup_table *table;
4151 struct gpiod_lookup *p;
4152 unsigned int count = 0;
4154 scoped_guard(mutex, &gpio_lookup_lock) {
4155 table = gpiod_find_lookup_table(dev);
4159 for (p = &table->table[0]; p->key; p++) {
4160 if ((con_id && p->con_id && !strcmp(con_id, p->con_id)) ||
4161 (!con_id && !p->con_id))
4172 static struct gpio_desc *gpiod_find_by_fwnode(struct fwnode_handle *fwnode,
4173 struct device *consumer,
4176 enum gpiod_flags *flags,
4177 unsigned long *lookupflags)
4179 const char *name = function_name_or_default(con_id);
4180 struct gpio_desc *desc = ERR_PTR(-ENOENT);
4182 if (is_of_node(fwnode)) {
4183 dev_dbg(consumer, "using DT '%pfw' for '%s' GPIO lookup\n", fwnode, name);
4184 desc = of_find_gpio(to_of_node(fwnode), con_id, idx, lookupflags);
4185 } else if (is_acpi_node(fwnode)) {
4186 dev_dbg(consumer, "using ACPI '%pfw' for '%s' GPIO lookup\n", fwnode, name);
4187 desc = acpi_find_gpio(fwnode, con_id, idx, flags, lookupflags);
4188 } else if (is_software_node(fwnode)) {
4189 dev_dbg(consumer, "using swnode '%pfw' for '%s' GPIO lookup\n", fwnode, name);
4190 desc = swnode_find_gpio(fwnode, con_id, idx, lookupflags);
4196 struct gpio_desc *gpiod_find_and_request(struct device *consumer,
4197 struct fwnode_handle *fwnode,
4200 enum gpiod_flags flags,
4202 bool platform_lookup_allowed)
4204 unsigned long lookupflags = GPIO_LOOKUP_FLAGS_DEFAULT;
4205 const char *name = function_name_or_default(con_id);
4207 * scoped_guard() is implemented as a for loop, meaning static
4208 * analyzers will complain about these two not being initialized.
4210 struct gpio_desc *desc = NULL;
4213 scoped_guard(srcu, &gpio_devices_srcu) {
4214 desc = gpiod_find_by_fwnode(fwnode, consumer, con_id, idx,
4215 &flags, &lookupflags);
4216 if (gpiod_not_found(desc) && platform_lookup_allowed) {
4218 * Either we are not using DT or ACPI, or their lookup
4219 * did not return a result. In that case, use platform
4220 * lookup as a fallback.
4223 "using lookup tables for GPIO lookup\n");
4224 desc = gpiod_find(consumer, con_id, idx, &lookupflags);
4228 dev_dbg(consumer, "No GPIO consumer %s found\n", name);
4233 * If a connection label was passed use that, else attempt to use
4234 * the device name as label
4236 ret = gpiod_request(desc, label);
4239 if (!(ret == -EBUSY && flags & GPIOD_FLAGS_BIT_NONEXCLUSIVE))
4240 return ERR_PTR(ret);
4243 * This happens when there are several consumers for
4244 * the same GPIO line: we just return here without
4245 * further initialization. It is a bit of a hack.
4246 * This is necessary to support fixed regulators.
4248 * FIXME: Make this more sane and safe.
4250 dev_info(consumer, "nonexclusive access to GPIO for %s\n", name);
4254 ret = gpiod_configure_flags(desc, con_id, lookupflags, flags);
4257 dev_dbg(consumer, "setup of GPIO %s failed\n", name);
4258 return ERR_PTR(ret);
4261 gpiod_line_state_notify(desc, GPIOLINE_CHANGED_REQUESTED);
4267 * fwnode_gpiod_get_index - obtain a GPIO from firmware node
4268 * @fwnode: handle of the firmware node
4269 * @con_id: function within the GPIO consumer
4270 * @index: index of the GPIO to obtain for the consumer
4271 * @flags: GPIO initialization flags
4272 * @label: label to attach to the requested GPIO
4274 * This function can be used for drivers that get their configuration
4275 * from opaque firmware.
4277 * The function properly finds the corresponding GPIO using whatever is the
4278 * underlying firmware interface and then makes sure that the GPIO
4279 * descriptor is requested before it is returned to the caller.
4282 * On successful request the GPIO pin is configured in accordance with
4285 * In case of error an ERR_PTR() is returned.
4287 struct gpio_desc *fwnode_gpiod_get_index(struct fwnode_handle *fwnode,
4290 enum gpiod_flags flags,
4293 return gpiod_find_and_request(NULL, fwnode, con_id, index, flags, label, false);
4295 EXPORT_SYMBOL_GPL(fwnode_gpiod_get_index);
4298 * gpiod_count - return the number of GPIOs associated with a device / function
4299 * or -ENOENT if no GPIO has been assigned to the requested function
4300 * @dev: GPIO consumer, can be NULL for system-global GPIOs
4301 * @con_id: function within the GPIO consumer
4303 int gpiod_count(struct device *dev, const char *con_id)
4305 const struct fwnode_handle *fwnode = dev ? dev_fwnode(dev) : NULL;
4306 int count = -ENOENT;
4308 if (is_of_node(fwnode))
4309 count = of_gpio_count(fwnode, con_id);
4310 else if (is_acpi_node(fwnode))
4311 count = acpi_gpio_count(fwnode, con_id);
4312 else if (is_software_node(fwnode))
4313 count = swnode_gpio_count(fwnode, con_id);
4316 count = platform_gpio_count(dev, con_id);
4320 EXPORT_SYMBOL_GPL(gpiod_count);
4323 * gpiod_get - obtain a GPIO for a given GPIO function
4324 * @dev: GPIO consumer, can be NULL for system-global GPIOs
4325 * @con_id: function within the GPIO consumer
4326 * @flags: optional GPIO initialization flags
4328 * Return the GPIO descriptor corresponding to the function con_id of device
4329 * dev, -ENOENT if no GPIO has been assigned to the requested function, or
4330 * another IS_ERR() code if an error occurred while trying to acquire the GPIO.
4332 struct gpio_desc *__must_check gpiod_get(struct device *dev, const char *con_id,
4333 enum gpiod_flags flags)
4335 return gpiod_get_index(dev, con_id, 0, flags);
4337 EXPORT_SYMBOL_GPL(gpiod_get);
4340 * gpiod_get_optional - obtain an optional GPIO for a given GPIO function
4341 * @dev: GPIO consumer, can be NULL for system-global GPIOs
4342 * @con_id: function within the GPIO consumer
4343 * @flags: optional GPIO initialization flags
4345 * This is equivalent to gpiod_get(), except that when no GPIO was assigned to
4346 * the requested function it will return NULL. This is convenient for drivers
4347 * that need to handle optional GPIOs.
4349 struct gpio_desc *__must_check gpiod_get_optional(struct device *dev,
4351 enum gpiod_flags flags)
4353 return gpiod_get_index_optional(dev, con_id, 0, flags);
4355 EXPORT_SYMBOL_GPL(gpiod_get_optional);
4359 * gpiod_configure_flags - helper function to configure a given GPIO
4360 * @desc: gpio whose value will be assigned
4361 * @con_id: function within the GPIO consumer
4362 * @lflags: bitmask of gpio_lookup_flags GPIO_* values - returned from
4363 * of_find_gpio() or of_get_gpio_hog()
4364 * @dflags: gpiod_flags - optional GPIO initialization flags
4366 * Return 0 on success, -ENOENT if no GPIO has been assigned to the
4367 * requested function and/or index, or another IS_ERR() code if an error
4368 * occurred while trying to acquire the GPIO.
4370 int gpiod_configure_flags(struct gpio_desc *desc, const char *con_id,
4371 unsigned long lflags, enum gpiod_flags dflags)
4373 const char *name = function_name_or_default(con_id);
4376 if (lflags & GPIO_ACTIVE_LOW)
4377 set_bit(FLAG_ACTIVE_LOW, &desc->flags);
4379 if (lflags & GPIO_OPEN_DRAIN)
4380 set_bit(FLAG_OPEN_DRAIN, &desc->flags);
4381 else if (dflags & GPIOD_FLAGS_BIT_OPEN_DRAIN) {
4383 * This enforces open drain mode from the consumer side.
4384 * This is necessary for some busses like I2C, but the lookup
4385 * should *REALLY* have specified them as open drain in the
4386 * first place, so print a little warning here.
4388 set_bit(FLAG_OPEN_DRAIN, &desc->flags);
4390 "enforced open drain please flag it properly in DT/ACPI DSDT/board file\n");
4393 if (lflags & GPIO_OPEN_SOURCE)
4394 set_bit(FLAG_OPEN_SOURCE, &desc->flags);
4396 if (((lflags & GPIO_PULL_UP) && (lflags & GPIO_PULL_DOWN)) ||
4397 ((lflags & GPIO_PULL_UP) && (lflags & GPIO_PULL_DISABLE)) ||
4398 ((lflags & GPIO_PULL_DOWN) && (lflags & GPIO_PULL_DISABLE))) {
4400 "multiple pull-up, pull-down or pull-disable enabled, invalid configuration\n");
4404 if (lflags & GPIO_PULL_UP)
4405 set_bit(FLAG_PULL_UP, &desc->flags);
4406 else if (lflags & GPIO_PULL_DOWN)
4407 set_bit(FLAG_PULL_DOWN, &desc->flags);
4408 else if (lflags & GPIO_PULL_DISABLE)
4409 set_bit(FLAG_BIAS_DISABLE, &desc->flags);
4411 ret = gpiod_set_transitory(desc, (lflags & GPIO_TRANSITORY));
4415 /* No particular flag request, return here... */
4416 if (!(dflags & GPIOD_FLAGS_BIT_DIR_SET)) {
4417 gpiod_dbg(desc, "no flags found for GPIO %s\n", name);
4422 if (dflags & GPIOD_FLAGS_BIT_DIR_OUT)
4423 ret = gpiod_direction_output(desc,
4424 !!(dflags & GPIOD_FLAGS_BIT_DIR_VAL));
4426 ret = gpiod_direction_input(desc);
4432 * gpiod_get_index - obtain a GPIO from a multi-index GPIO function
4433 * @dev: GPIO consumer, can be NULL for system-global GPIOs
4434 * @con_id: function within the GPIO consumer
4435 * @idx: index of the GPIO to obtain in the consumer
4436 * @flags: optional GPIO initialization flags
4438 * This variant of gpiod_get() allows to access GPIOs other than the first
4439 * defined one for functions that define several GPIOs.
4441 * Return a valid GPIO descriptor, -ENOENT if no GPIO has been assigned to the
4442 * requested function and/or index, or another IS_ERR() code if an error
4443 * occurred while trying to acquire the GPIO.
4445 struct gpio_desc *__must_check gpiod_get_index(struct device *dev,
4448 enum gpiod_flags flags)
4450 struct fwnode_handle *fwnode = dev ? dev_fwnode(dev) : NULL;
4451 const char *devname = dev ? dev_name(dev) : "?";
4452 const char *label = con_id ?: devname;
4454 return gpiod_find_and_request(dev, fwnode, con_id, idx, flags, label, true);
4456 EXPORT_SYMBOL_GPL(gpiod_get_index);
4459 * gpiod_get_index_optional - obtain an optional GPIO from a multi-index GPIO
4461 * @dev: GPIO consumer, can be NULL for system-global GPIOs
4462 * @con_id: function within the GPIO consumer
4463 * @index: index of the GPIO to obtain in the consumer
4464 * @flags: optional GPIO initialization flags
4466 * This is equivalent to gpiod_get_index(), except that when no GPIO with the
4467 * specified index was assigned to the requested function it will return NULL.
4468 * This is convenient for drivers that need to handle optional GPIOs.
4470 struct gpio_desc *__must_check gpiod_get_index_optional(struct device *dev,
4473 enum gpiod_flags flags)
4475 struct gpio_desc *desc;
4477 desc = gpiod_get_index(dev, con_id, index, flags);
4478 if (gpiod_not_found(desc))
4483 EXPORT_SYMBOL_GPL(gpiod_get_index_optional);
4486 * gpiod_hog - Hog the specified GPIO desc given the provided flags
4487 * @desc: gpio whose value will be assigned
4488 * @name: gpio line name
4489 * @lflags: bitmask of gpio_lookup_flags GPIO_* values - returned from
4490 * of_find_gpio() or of_get_gpio_hog()
4491 * @dflags: gpiod_flags - optional GPIO initialization flags
4493 int gpiod_hog(struct gpio_desc *desc, const char *name,
4494 unsigned long lflags, enum gpiod_flags dflags)
4496 struct gpio_device *gdev = desc->gdev;
4497 struct gpio_desc *local_desc;
4501 CLASS(gpio_chip_guard, guard)(desc);
4505 if (test_and_set_bit(FLAG_IS_HOGGED, &desc->flags))
4508 hwnum = gpio_chip_hwgpio(desc);
4510 local_desc = gpiochip_request_own_desc(guard.gc, hwnum, name,
4512 if (IS_ERR(local_desc)) {
4513 clear_bit(FLAG_IS_HOGGED, &desc->flags);
4514 ret = PTR_ERR(local_desc);
4515 pr_err("requesting hog GPIO %s (chip %s, offset %d) failed, %d\n",
4516 name, gdev->label, hwnum, ret);
4520 gpiod_dbg(desc, "hogged as %s%s\n",
4521 (dflags & GPIOD_FLAGS_BIT_DIR_OUT) ? "output" : "input",
4522 (dflags & GPIOD_FLAGS_BIT_DIR_OUT) ?
4523 (dflags & GPIOD_FLAGS_BIT_DIR_VAL) ? "/high" : "/low" : "");
4529 * gpiochip_free_hogs - Scan gpio-controller chip and release GPIO hog
4530 * @gc: gpio chip to act on
4532 static void gpiochip_free_hogs(struct gpio_chip *gc)
4534 struct gpio_desc *desc;
4536 for_each_gpio_desc_with_flag(gc, desc, FLAG_IS_HOGGED)
4537 gpiochip_free_own_desc(desc);
4541 * gpiod_get_array - obtain multiple GPIOs from a multi-index GPIO function
4542 * @dev: GPIO consumer, can be NULL for system-global GPIOs
4543 * @con_id: function within the GPIO consumer
4544 * @flags: optional GPIO initialization flags
4546 * This function acquires all the GPIOs defined under a given function.
4548 * Return a struct gpio_descs containing an array of descriptors, -ENOENT if
4549 * no GPIO has been assigned to the requested function, or another IS_ERR()
4550 * code if an error occurred while trying to acquire the GPIOs.
4552 struct gpio_descs *__must_check gpiod_get_array(struct device *dev,
4554 enum gpiod_flags flags)
4556 struct gpio_desc *desc;
4557 struct gpio_descs *descs;
4558 struct gpio_array *array_info = NULL;
4559 struct gpio_chip *gc;
4560 int count, bitmap_size;
4563 count = gpiod_count(dev, con_id);
4565 return ERR_PTR(count);
4567 descs_size = struct_size(descs, desc, count);
4568 descs = kzalloc(descs_size, GFP_KERNEL);
4570 return ERR_PTR(-ENOMEM);
4572 for (descs->ndescs = 0; descs->ndescs < count; descs->ndescs++) {
4573 desc = gpiod_get_index(dev, con_id, descs->ndescs, flags);
4575 gpiod_put_array(descs);
4576 return ERR_CAST(desc);
4579 descs->desc[descs->ndescs] = desc;
4581 gc = gpiod_to_chip(desc);
4583 * If pin hardware number of array member 0 is also 0, select
4584 * its chip as a candidate for fast bitmap processing path.
4586 if (descs->ndescs == 0 && gpio_chip_hwgpio(desc) == 0) {
4587 struct gpio_descs *array;
4589 bitmap_size = BITS_TO_LONGS(gc->ngpio > count ?
4592 array = krealloc(descs, descs_size +
4593 struct_size(array_info, invert_mask, 3 * bitmap_size),
4594 GFP_KERNEL | __GFP_ZERO);
4596 gpiod_put_array(descs);
4597 return ERR_PTR(-ENOMEM);
4602 array_info = (void *)descs + descs_size;
4603 array_info->get_mask = array_info->invert_mask +
4605 array_info->set_mask = array_info->get_mask +
4608 array_info->desc = descs->desc;
4609 array_info->size = count;
4610 array_info->chip = gc;
4611 bitmap_set(array_info->get_mask, descs->ndescs,
4612 count - descs->ndescs);
4613 bitmap_set(array_info->set_mask, descs->ndescs,
4614 count - descs->ndescs);
4615 descs->info = array_info;
4618 /* If there is no cache for fast bitmap processing path, continue */
4622 /* Unmark array members which don't belong to the 'fast' chip */
4623 if (array_info->chip != gc) {
4624 __clear_bit(descs->ndescs, array_info->get_mask);
4625 __clear_bit(descs->ndescs, array_info->set_mask);
4628 * Detect array members which belong to the 'fast' chip
4629 * but their pins are not in hardware order.
4631 else if (gpio_chip_hwgpio(desc) != descs->ndescs) {
4633 * Don't use fast path if all array members processed so
4634 * far belong to the same chip as this one but its pin
4635 * hardware number is different from its array index.
4637 if (bitmap_full(array_info->get_mask, descs->ndescs)) {
4640 __clear_bit(descs->ndescs,
4641 array_info->get_mask);
4642 __clear_bit(descs->ndescs,
4643 array_info->set_mask);
4646 /* Exclude open drain or open source from fast output */
4647 if (gpiochip_line_is_open_drain(gc, descs->ndescs) ||
4648 gpiochip_line_is_open_source(gc, descs->ndescs))
4649 __clear_bit(descs->ndescs,
4650 array_info->set_mask);
4651 /* Identify 'fast' pins which require invertion */
4652 if (gpiod_is_active_low(desc))
4653 __set_bit(descs->ndescs,
4654 array_info->invert_mask);
4659 "GPIO array info: chip=%s, size=%d, get_mask=%lx, set_mask=%lx, invert_mask=%lx\n",
4660 array_info->chip->label, array_info->size,
4661 *array_info->get_mask, *array_info->set_mask,
4662 *array_info->invert_mask);
4665 EXPORT_SYMBOL_GPL(gpiod_get_array);
4668 * gpiod_get_array_optional - obtain multiple GPIOs from a multi-index GPIO
4670 * @dev: GPIO consumer, can be NULL for system-global GPIOs
4671 * @con_id: function within the GPIO consumer
4672 * @flags: optional GPIO initialization flags
4674 * This is equivalent to gpiod_get_array(), except that when no GPIO was
4675 * assigned to the requested function it will return NULL.
4677 struct gpio_descs *__must_check gpiod_get_array_optional(struct device *dev,
4679 enum gpiod_flags flags)
4681 struct gpio_descs *descs;
4683 descs = gpiod_get_array(dev, con_id, flags);
4684 if (gpiod_not_found(descs))
4689 EXPORT_SYMBOL_GPL(gpiod_get_array_optional);
4692 * gpiod_put - dispose of a GPIO descriptor
4693 * @desc: GPIO descriptor to dispose of
4695 * No descriptor can be used after gpiod_put() has been called on it.
4697 void gpiod_put(struct gpio_desc *desc)
4702 EXPORT_SYMBOL_GPL(gpiod_put);
4705 * gpiod_put_array - dispose of multiple GPIO descriptors
4706 * @descs: struct gpio_descs containing an array of descriptors
4708 void gpiod_put_array(struct gpio_descs *descs)
4712 for (i = 0; i < descs->ndescs; i++)
4713 gpiod_put(descs->desc[i]);
4717 EXPORT_SYMBOL_GPL(gpiod_put_array);
4719 static int gpio_stub_drv_probe(struct device *dev)
4722 * The DT node of some GPIO chips have a "compatible" property, but
4723 * never have a struct device added and probed by a driver to register
4724 * the GPIO chip with gpiolib. In such cases, fw_devlink=on will cause
4725 * the consumers of the GPIO chip to get probe deferred forever because
4726 * they will be waiting for a device associated with the GPIO chip
4727 * firmware node to get added and bound to a driver.
4729 * To allow these consumers to probe, we associate the struct
4730 * gpio_device of the GPIO chip with the firmware node and then simply
4731 * bind it to this stub driver.
4736 static struct device_driver gpio_stub_drv = {
4737 .name = "gpio_stub_drv",
4738 .bus = &gpio_bus_type,
4739 .probe = gpio_stub_drv_probe,
4742 static int __init gpiolib_dev_init(void)
4746 /* Register GPIO sysfs bus */
4747 ret = bus_register(&gpio_bus_type);
4749 pr_err("gpiolib: could not register GPIO bus type\n");
4753 ret = driver_register(&gpio_stub_drv);
4755 pr_err("gpiolib: could not register GPIO stub driver\n");
4756 bus_unregister(&gpio_bus_type);
4760 ret = alloc_chrdev_region(&gpio_devt, 0, GPIO_DEV_MAX, GPIOCHIP_NAME);
4762 pr_err("gpiolib: failed to allocate char dev region\n");
4763 driver_unregister(&gpio_stub_drv);
4764 bus_unregister(&gpio_bus_type);
4768 gpiolib_initialized = true;
4769 gpiochip_setup_devs();
4771 #if IS_ENABLED(CONFIG_OF_DYNAMIC) && IS_ENABLED(CONFIG_OF_GPIO)
4772 WARN_ON(of_reconfig_notifier_register(&gpio_of_notifier));
4773 #endif /* CONFIG_OF_DYNAMIC && CONFIG_OF_GPIO */
4777 core_initcall(gpiolib_dev_init);
4779 #ifdef CONFIG_DEBUG_FS
4781 static void gpiolib_dbg_show(struct seq_file *s, struct gpio_device *gdev)
4783 bool active_low, is_irq, is_out;
4784 unsigned int gpio = gdev->base;
4785 struct gpio_desc *desc;
4786 struct gpio_chip *gc;
4789 guard(srcu)(&gdev->srcu);
4791 gc = srcu_dereference(gdev->chip, &gdev->srcu);
4793 seq_puts(s, "Underlying GPIO chip is gone\n");
4797 for_each_gpio_desc(gc, desc) {
4798 guard(srcu)(&desc->gdev->desc_srcu);
4799 if (test_bit(FLAG_REQUESTED, &desc->flags)) {
4800 gpiod_get_direction(desc);
4801 is_out = test_bit(FLAG_IS_OUT, &desc->flags);
4802 value = gpio_chip_get_value(gc, desc);
4803 is_irq = test_bit(FLAG_USED_AS_IRQ, &desc->flags);
4804 active_low = test_bit(FLAG_ACTIVE_LOW, &desc->flags);
4805 seq_printf(s, " gpio-%-3d (%-20.20s|%-20.20s) %s %s %s%s\n",
4806 gpio, desc->name ?: "", gpiod_get_label(desc),
4807 is_out ? "out" : "in ",
4808 value >= 0 ? (value ? "hi" : "lo") : "? ",
4809 is_irq ? "IRQ " : "",
4810 active_low ? "ACTIVE LOW" : "");
4811 } else if (desc->name) {
4812 seq_printf(s, " gpio-%-3d (%-20.20s)\n", gpio, desc->name);
4819 struct gpiolib_seq_priv {
4824 static void *gpiolib_seq_start(struct seq_file *s, loff_t *pos)
4826 struct gpiolib_seq_priv *priv;
4827 struct gpio_device *gdev;
4828 loff_t index = *pos;
4830 priv = kzalloc(sizeof(*priv), GFP_KERNEL);
4835 priv->idx = srcu_read_lock(&gpio_devices_srcu);
4837 list_for_each_entry_srcu(gdev, &gpio_devices, list,
4838 srcu_read_lock_held(&gpio_devices_srcu)) {
4846 static void *gpiolib_seq_next(struct seq_file *s, void *v, loff_t *pos)
4848 struct gpiolib_seq_priv *priv = s->private;
4849 struct gpio_device *gdev = v, *next;
4851 next = list_entry_rcu(gdev->list.next, struct gpio_device, list);
4852 gdev = &next->list == &gpio_devices ? NULL : next;
4853 priv->newline = true;
4859 static void gpiolib_seq_stop(struct seq_file *s, void *v)
4861 struct gpiolib_seq_priv *priv = s->private;
4863 srcu_read_unlock(&gpio_devices_srcu, priv->idx);
4867 static int gpiolib_seq_show(struct seq_file *s, void *v)
4869 struct gpiolib_seq_priv *priv = s->private;
4870 struct gpio_device *gdev = v;
4871 struct gpio_chip *gc;
4872 struct device *parent;
4874 guard(srcu)(&gdev->srcu);
4876 gc = srcu_dereference(gdev->chip, &gdev->srcu);
4878 seq_printf(s, "%s%s: (dangling chip)",
4879 priv->newline ? "\n" : "",
4880 dev_name(&gdev->dev));
4884 seq_printf(s, "%s%s: GPIOs %d-%d", priv->newline ? "\n" : "",
4885 dev_name(&gdev->dev),
4886 gdev->base, gdev->base + gdev->ngpio - 1);
4887 parent = gc->parent;
4889 seq_printf(s, ", parent: %s/%s",
4890 parent->bus ? parent->bus->name : "no-bus",
4893 seq_printf(s, ", %s", gc->label);
4895 seq_printf(s, ", can sleep");
4896 seq_printf(s, ":\n");
4899 gc->dbg_show(s, gc);
4901 gpiolib_dbg_show(s, gdev);
4906 static const struct seq_operations gpiolib_sops = {
4907 .start = gpiolib_seq_start,
4908 .next = gpiolib_seq_next,
4909 .stop = gpiolib_seq_stop,
4910 .show = gpiolib_seq_show,
4912 DEFINE_SEQ_ATTRIBUTE(gpiolib);
4914 static int __init gpiolib_debugfs_init(void)
4916 /* /sys/kernel/debug/gpio */
4917 debugfs_create_file("gpio", 0444, NULL, NULL, &gpiolib_fops);
4920 subsys_initcall(gpiolib_debugfs_init);
4922 #endif /* DEBUG_FS */