1 // SPDX-License-Identifier: GPL-2.0
2 #include <linux/bitmap.h>
3 #include <linux/kernel.h>
4 #include <linux/module.h>
5 #include <linux/interrupt.h>
7 #include <linux/spinlock.h>
8 #include <linux/list.h>
9 #include <linux/device.h>
10 #include <linux/err.h>
11 #include <linux/debugfs.h>
12 #include <linux/seq_file.h>
13 #include <linux/gpio.h>
14 #include <linux/idr.h>
15 #include <linux/slab.h>
16 #include <linux/acpi.h>
17 #include <linux/gpio/driver.h>
18 #include <linux/gpio/machine.h>
19 #include <linux/pinctrl/consumer.h>
20 #include <linux/cdev.h>
22 #include <linux/uaccess.h>
23 #include <linux/compat.h>
24 #include <linux/anon_inodes.h>
25 #include <linux/file.h>
26 #include <linux/kfifo.h>
27 #include <linux/poll.h>
28 #include <linux/timekeeping.h>
29 #include <uapi/linux/gpio.h>
32 #include "gpiolib-of.h"
33 #include "gpiolib-acpi.h"
35 #define CREATE_TRACE_POINTS
36 #include <trace/events/gpio.h>
38 /* Implementation infrastructure for GPIO interfaces.
40 * The GPIO programming interface allows for inlining speed-critical
41 * get/set operations for common cases, so that access to SOC-integrated
42 * GPIOs can sometimes cost only an instruction or two per bit.
46 /* When debugging, extend minimal trust to callers and platform code.
47 * Also emit diagnostic messages that may help initial bringup, when
48 * board setup or driver bugs are most common.
50 * Otherwise, minimize overhead in what may be bitbanging codepaths.
53 #define extra_checks 1
55 #define extra_checks 0
58 /* Device and char device-related information */
59 static DEFINE_IDA(gpio_ida);
60 static dev_t gpio_devt;
61 #define GPIO_DEV_MAX 256 /* 256 GPIO chip devices supported */
62 static struct bus_type gpio_bus_type = {
67 * Number of GPIOs to use for the fast path in set array
69 #define FASTPATH_NGPIO CONFIG_GPIOLIB_FASTPATH_LIMIT
71 /* gpio_lock prevents conflicts during gpio_desc[] table updates.
72 * While any GPIO is requested, its gpio_chip is not removable;
73 * each GPIO's "requested" flag serves as a lock and refcount.
75 DEFINE_SPINLOCK(gpio_lock);
77 static DEFINE_MUTEX(gpio_lookup_lock);
78 static LIST_HEAD(gpio_lookup_list);
79 LIST_HEAD(gpio_devices);
81 static DEFINE_MUTEX(gpio_machine_hogs_mutex);
82 static LIST_HEAD(gpio_machine_hogs);
84 static void gpiochip_free_hogs(struct gpio_chip *chip);
85 static int gpiochip_add_irqchip(struct gpio_chip *gpiochip,
86 struct lock_class_key *lock_key,
87 struct lock_class_key *request_key);
88 static void gpiochip_irqchip_remove(struct gpio_chip *gpiochip);
89 static int gpiochip_irqchip_init_hw(struct gpio_chip *gpiochip);
90 static int gpiochip_irqchip_init_valid_mask(struct gpio_chip *gpiochip);
91 static void gpiochip_irqchip_free_valid_mask(struct gpio_chip *gpiochip);
93 static bool gpiolib_initialized;
95 static inline void desc_set_label(struct gpio_desc *d, const char *label)
101 * gpio_to_desc - Convert a GPIO number to its descriptor
102 * @gpio: global GPIO number
105 * The GPIO descriptor associated with the given GPIO, or %NULL if no GPIO
106 * with the given number exists in the system.
108 struct gpio_desc *gpio_to_desc(unsigned gpio)
110 struct gpio_device *gdev;
113 spin_lock_irqsave(&gpio_lock, flags);
115 list_for_each_entry(gdev, &gpio_devices, list) {
116 if (gdev->base <= gpio &&
117 gdev->base + gdev->ngpio > gpio) {
118 spin_unlock_irqrestore(&gpio_lock, flags);
119 return &gdev->descs[gpio - gdev->base];
123 spin_unlock_irqrestore(&gpio_lock, flags);
125 if (!gpio_is_valid(gpio))
126 WARN(1, "invalid GPIO %d\n", gpio);
130 EXPORT_SYMBOL_GPL(gpio_to_desc);
133 * gpiochip_get_desc - get the GPIO descriptor corresponding to the given
134 * hardware number for this chip
136 * @hwnum: hardware number of the GPIO for this chip
139 * A pointer to the GPIO descriptor or %ERR_PTR(-EINVAL) if no GPIO exists
140 * in the given chip for the specified hardware number.
142 struct gpio_desc *gpiochip_get_desc(struct gpio_chip *chip,
145 struct gpio_device *gdev = chip->gpiodev;
147 if (hwnum >= gdev->ngpio)
148 return ERR_PTR(-EINVAL);
150 return &gdev->descs[hwnum];
152 EXPORT_SYMBOL_GPL(gpiochip_get_desc);
155 * desc_to_gpio - convert a GPIO descriptor to the integer namespace
156 * @desc: GPIO descriptor
158 * This should disappear in the future but is needed since we still
159 * use GPIO numbers for error messages and sysfs nodes.
162 * The global GPIO number for the GPIO specified by its descriptor.
164 int desc_to_gpio(const struct gpio_desc *desc)
166 return desc->gdev->base + (desc - &desc->gdev->descs[0]);
168 EXPORT_SYMBOL_GPL(desc_to_gpio);
172 * gpiod_to_chip - Return the GPIO chip to which a GPIO descriptor belongs
173 * @desc: descriptor to return the chip of
175 struct gpio_chip *gpiod_to_chip(const struct gpio_desc *desc)
177 if (!desc || !desc->gdev)
179 return desc->gdev->chip;
181 EXPORT_SYMBOL_GPL(gpiod_to_chip);
183 /* dynamic allocation of GPIOs, e.g. on a hotplugged device */
184 static int gpiochip_find_base(int ngpio)
186 struct gpio_device *gdev;
187 int base = ARCH_NR_GPIOS - ngpio;
189 list_for_each_entry_reverse(gdev, &gpio_devices, list) {
190 /* found a free space? */
191 if (gdev->base + gdev->ngpio <= base)
194 /* nope, check the space right before the chip */
195 base = gdev->base - ngpio;
198 if (gpio_is_valid(base)) {
199 pr_debug("%s: found new base at %d\n", __func__, base);
202 pr_err("%s: cannot find free range\n", __func__);
208 * gpiod_get_direction - return the current direction of a GPIO
209 * @desc: GPIO to get the direction of
211 * Returns 0 for output, 1 for input, or an error code in case of error.
213 * This function may sleep if gpiod_cansleep() is true.
215 int gpiod_get_direction(struct gpio_desc *desc)
217 struct gpio_chip *chip;
221 chip = gpiod_to_chip(desc);
222 offset = gpio_chip_hwgpio(desc);
225 * Open drain emulation using input mode may incorrectly report
226 * input here, fix that up.
228 if (test_bit(FLAG_OPEN_DRAIN, &desc->flags) &&
229 test_bit(FLAG_IS_OUT, &desc->flags))
232 if (!chip->get_direction)
235 ret = chip->get_direction(chip, offset);
239 /* GPIOF_DIR_IN or other positive, otherwise GPIOF_DIR_OUT */
243 assign_bit(FLAG_IS_OUT, &desc->flags, !ret);
247 EXPORT_SYMBOL_GPL(gpiod_get_direction);
250 * Add a new chip to the global chips list, keeping the list of chips sorted
251 * by range(means [base, base + ngpio - 1]) order.
253 * Return -EBUSY if the new chip overlaps with some other chip's integer
256 static int gpiodev_add_to_list(struct gpio_device *gdev)
258 struct gpio_device *prev, *next;
260 if (list_empty(&gpio_devices)) {
261 /* initial entry in list */
262 list_add_tail(&gdev->list, &gpio_devices);
266 next = list_entry(gpio_devices.next, struct gpio_device, list);
267 if (gdev->base + gdev->ngpio <= next->base) {
268 /* add before first entry */
269 list_add(&gdev->list, &gpio_devices);
273 prev = list_entry(gpio_devices.prev, struct gpio_device, list);
274 if (prev->base + prev->ngpio <= gdev->base) {
275 /* add behind last entry */
276 list_add_tail(&gdev->list, &gpio_devices);
280 list_for_each_entry_safe(prev, next, &gpio_devices, list) {
281 /* at the end of the list */
282 if (&next->list == &gpio_devices)
285 /* add between prev and next */
286 if (prev->base + prev->ngpio <= gdev->base
287 && gdev->base + gdev->ngpio <= next->base) {
288 list_add(&gdev->list, &prev->list);
293 dev_err(&gdev->dev, "GPIO integer space overlap, cannot add chip\n");
298 * Convert a GPIO name to its descriptor
300 static struct gpio_desc *gpio_name_to_desc(const char * const name)
302 struct gpio_device *gdev;
305 spin_lock_irqsave(&gpio_lock, flags);
307 list_for_each_entry(gdev, &gpio_devices, list) {
310 for (i = 0; i != gdev->ngpio; ++i) {
311 struct gpio_desc *desc = &gdev->descs[i];
313 if (!desc->name || !name)
316 if (!strcmp(desc->name, name)) {
317 spin_unlock_irqrestore(&gpio_lock, flags);
323 spin_unlock_irqrestore(&gpio_lock, flags);
329 * Takes the names from gc->names and checks if they are all unique. If they
330 * are, they are assigned to their gpio descriptors.
332 * Warning if one of the names is already used for a different GPIO.
334 static int gpiochip_set_desc_names(struct gpio_chip *gc)
336 struct gpio_device *gdev = gc->gpiodev;
342 /* First check all names if they are unique */
343 for (i = 0; i != gc->ngpio; ++i) {
344 struct gpio_desc *gpio;
346 gpio = gpio_name_to_desc(gc->names[i]);
349 "Detected name collision for GPIO name '%s'\n",
353 /* Then add all names to the GPIO descriptors */
354 for (i = 0; i != gc->ngpio; ++i)
355 gdev->descs[i].name = gc->names[i];
360 static unsigned long *gpiochip_allocate_mask(struct gpio_chip *chip)
364 p = bitmap_alloc(chip->ngpio, GFP_KERNEL);
368 /* Assume by default all GPIOs are valid */
369 bitmap_fill(p, chip->ngpio);
374 static int gpiochip_alloc_valid_mask(struct gpio_chip *gc)
376 if (!(of_gpio_need_valid_mask(gc) || gc->init_valid_mask))
379 gc->valid_mask = gpiochip_allocate_mask(gc);
386 static int gpiochip_init_valid_mask(struct gpio_chip *gc)
388 if (gc->init_valid_mask)
389 return gc->init_valid_mask(gc,
396 static void gpiochip_free_valid_mask(struct gpio_chip *gpiochip)
398 bitmap_free(gpiochip->valid_mask);
399 gpiochip->valid_mask = NULL;
402 static int gpiochip_add_pin_ranges(struct gpio_chip *gc)
404 if (gc->add_pin_ranges)
405 return gc->add_pin_ranges(gc);
410 bool gpiochip_line_is_valid(const struct gpio_chip *gpiochip,
413 /* No mask means all valid */
414 if (likely(!gpiochip->valid_mask))
416 return test_bit(offset, gpiochip->valid_mask);
418 EXPORT_SYMBOL_GPL(gpiochip_line_is_valid);
421 * GPIO line handle management
425 * struct linehandle_state - contains the state of a userspace handle
426 * @gdev: the GPIO device the handle pertains to
427 * @label: consumer label used to tag descriptors
428 * @descs: the GPIO descriptors held by this handle
429 * @numdescs: the number of descriptors held in the descs array
431 struct linehandle_state {
432 struct gpio_device *gdev;
434 struct gpio_desc *descs[GPIOHANDLES_MAX];
438 #define GPIOHANDLE_REQUEST_VALID_FLAGS \
439 (GPIOHANDLE_REQUEST_INPUT | \
440 GPIOHANDLE_REQUEST_OUTPUT | \
441 GPIOHANDLE_REQUEST_ACTIVE_LOW | \
442 GPIOHANDLE_REQUEST_BIAS_PULL_UP | \
443 GPIOHANDLE_REQUEST_BIAS_PULL_DOWN | \
444 GPIOHANDLE_REQUEST_BIAS_DISABLE | \
445 GPIOHANDLE_REQUEST_OPEN_DRAIN | \
446 GPIOHANDLE_REQUEST_OPEN_SOURCE)
448 static int linehandle_validate_flags(u32 flags)
450 /* Return an error if an unknown flag is set */
451 if (flags & ~GPIOHANDLE_REQUEST_VALID_FLAGS)
455 * Do not allow both INPUT & OUTPUT flags to be set as they are
458 if ((flags & GPIOHANDLE_REQUEST_INPUT) &&
459 (flags & GPIOHANDLE_REQUEST_OUTPUT))
463 * Do not allow OPEN_SOURCE & OPEN_DRAIN flags in a single request. If
464 * the hardware actually supports enabling both at the same time the
465 * electrical result would be disastrous.
467 if ((flags & GPIOHANDLE_REQUEST_OPEN_DRAIN) &&
468 (flags & GPIOHANDLE_REQUEST_OPEN_SOURCE))
471 /* OPEN_DRAIN and OPEN_SOURCE flags only make sense for output mode. */
472 if (!(flags & GPIOHANDLE_REQUEST_OUTPUT) &&
473 ((flags & GPIOHANDLE_REQUEST_OPEN_DRAIN) ||
474 (flags & GPIOHANDLE_REQUEST_OPEN_SOURCE)))
477 /* Bias flags only allowed for input or output mode. */
478 if (!((flags & GPIOHANDLE_REQUEST_INPUT) ||
479 (flags & GPIOHANDLE_REQUEST_OUTPUT)) &&
480 ((flags & GPIOHANDLE_REQUEST_BIAS_DISABLE) ||
481 (flags & GPIOHANDLE_REQUEST_BIAS_PULL_UP) ||
482 (flags & GPIOHANDLE_REQUEST_BIAS_PULL_DOWN)))
485 /* Only one bias flag can be set. */
486 if (((flags & GPIOHANDLE_REQUEST_BIAS_DISABLE) &&
487 (flags & (GPIOHANDLE_REQUEST_BIAS_PULL_DOWN |
488 GPIOHANDLE_REQUEST_BIAS_PULL_UP))) ||
489 ((flags & GPIOHANDLE_REQUEST_BIAS_PULL_DOWN) &&
490 (flags & GPIOHANDLE_REQUEST_BIAS_PULL_UP)))
496 static long linehandle_set_config(struct linehandle_state *lh,
499 struct gpiohandle_config gcnf;
500 struct gpio_desc *desc;
503 unsigned long *flagsp;
505 if (copy_from_user(&gcnf, ip, sizeof(gcnf)))
509 ret = linehandle_validate_flags(lflags);
513 for (i = 0; i < lh->numdescs; i++) {
515 flagsp = &desc->flags;
517 assign_bit(FLAG_ACTIVE_LOW, flagsp,
518 lflags & GPIOHANDLE_REQUEST_ACTIVE_LOW);
520 assign_bit(FLAG_OPEN_DRAIN, flagsp,
521 lflags & GPIOHANDLE_REQUEST_OPEN_DRAIN);
523 assign_bit(FLAG_OPEN_SOURCE, flagsp,
524 lflags & GPIOHANDLE_REQUEST_OPEN_SOURCE);
526 assign_bit(FLAG_PULL_UP, flagsp,
527 lflags & GPIOHANDLE_REQUEST_BIAS_PULL_UP);
529 assign_bit(FLAG_PULL_DOWN, flagsp,
530 lflags & GPIOHANDLE_REQUEST_BIAS_PULL_DOWN);
532 assign_bit(FLAG_BIAS_DISABLE, flagsp,
533 lflags & GPIOHANDLE_REQUEST_BIAS_DISABLE);
536 * Lines have to be requested explicitly for input
537 * or output, else the line will be treated "as is".
539 if (lflags & GPIOHANDLE_REQUEST_OUTPUT) {
540 int val = !!gcnf.default_values[i];
542 ret = gpiod_direction_output(desc, val);
545 } else if (lflags & GPIOHANDLE_REQUEST_INPUT) {
546 ret = gpiod_direction_input(desc);
554 static long linehandle_ioctl(struct file *filep, unsigned int cmd,
557 struct linehandle_state *lh = filep->private_data;
558 void __user *ip = (void __user *)arg;
559 struct gpiohandle_data ghd;
560 DECLARE_BITMAP(vals, GPIOHANDLES_MAX);
563 if (cmd == GPIOHANDLE_GET_LINE_VALUES_IOCTL) {
564 /* NOTE: It's ok to read values of output lines. */
565 int ret = gpiod_get_array_value_complex(false,
574 memset(&ghd, 0, sizeof(ghd));
575 for (i = 0; i < lh->numdescs; i++)
576 ghd.values[i] = test_bit(i, vals);
578 if (copy_to_user(ip, &ghd, sizeof(ghd)))
582 } else if (cmd == GPIOHANDLE_SET_LINE_VALUES_IOCTL) {
584 * All line descriptors were created at once with the same
585 * flags so just check if the first one is really output.
587 if (!test_bit(FLAG_IS_OUT, &lh->descs[0]->flags))
590 if (copy_from_user(&ghd, ip, sizeof(ghd)))
593 /* Clamp all values to [0,1] */
594 for (i = 0; i < lh->numdescs; i++)
595 __assign_bit(i, vals, ghd.values[i]);
597 /* Reuse the array setting function */
598 return gpiod_set_array_value_complex(false,
604 } else if (cmd == GPIOHANDLE_SET_CONFIG_IOCTL) {
605 return linehandle_set_config(lh, ip);
611 static long linehandle_ioctl_compat(struct file *filep, unsigned int cmd,
614 return linehandle_ioctl(filep, cmd, (unsigned long)compat_ptr(arg));
618 static int linehandle_release(struct inode *inode, struct file *filep)
620 struct linehandle_state *lh = filep->private_data;
621 struct gpio_device *gdev = lh->gdev;
624 for (i = 0; i < lh->numdescs; i++)
625 gpiod_free(lh->descs[i]);
628 put_device(&gdev->dev);
632 static const struct file_operations linehandle_fileops = {
633 .release = linehandle_release,
634 .owner = THIS_MODULE,
635 .llseek = noop_llseek,
636 .unlocked_ioctl = linehandle_ioctl,
638 .compat_ioctl = linehandle_ioctl_compat,
642 static int linehandle_create(struct gpio_device *gdev, void __user *ip)
644 struct gpiohandle_request handlereq;
645 struct linehandle_state *lh;
647 int fd, i, count = 0, ret;
650 if (copy_from_user(&handlereq, ip, sizeof(handlereq)))
652 if ((handlereq.lines == 0) || (handlereq.lines > GPIOHANDLES_MAX))
655 lflags = handlereq.flags;
657 ret = linehandle_validate_flags(lflags);
661 lh = kzalloc(sizeof(*lh), GFP_KERNEL);
665 get_device(&gdev->dev);
667 /* Make sure this is terminated */
668 handlereq.consumer_label[sizeof(handlereq.consumer_label)-1] = '\0';
669 if (strlen(handlereq.consumer_label)) {
670 lh->label = kstrdup(handlereq.consumer_label,
678 /* Request each GPIO */
679 for (i = 0; i < handlereq.lines; i++) {
680 u32 offset = handlereq.lineoffsets[i];
681 struct gpio_desc *desc = gpiochip_get_desc(gdev->chip, offset);
688 ret = gpiod_request(desc, lh->label);
694 if (lflags & GPIOHANDLE_REQUEST_ACTIVE_LOW)
695 set_bit(FLAG_ACTIVE_LOW, &desc->flags);
696 if (lflags & GPIOHANDLE_REQUEST_OPEN_DRAIN)
697 set_bit(FLAG_OPEN_DRAIN, &desc->flags);
698 if (lflags & GPIOHANDLE_REQUEST_OPEN_SOURCE)
699 set_bit(FLAG_OPEN_SOURCE, &desc->flags);
700 if (lflags & GPIOHANDLE_REQUEST_BIAS_DISABLE)
701 set_bit(FLAG_BIAS_DISABLE, &desc->flags);
702 if (lflags & GPIOHANDLE_REQUEST_BIAS_PULL_DOWN)
703 set_bit(FLAG_PULL_DOWN, &desc->flags);
704 if (lflags & GPIOHANDLE_REQUEST_BIAS_PULL_UP)
705 set_bit(FLAG_PULL_UP, &desc->flags);
707 ret = gpiod_set_transitory(desc, false);
712 * Lines have to be requested explicitly for input
713 * or output, else the line will be treated "as is".
715 if (lflags & GPIOHANDLE_REQUEST_OUTPUT) {
716 int val = !!handlereq.default_values[i];
718 ret = gpiod_direction_output(desc, val);
721 } else if (lflags & GPIOHANDLE_REQUEST_INPUT) {
722 ret = gpiod_direction_input(desc);
726 dev_dbg(&gdev->dev, "registered chardev handle for line %d\n",
729 /* Let i point at the last handle */
731 lh->numdescs = handlereq.lines;
733 fd = get_unused_fd_flags(O_RDONLY | O_CLOEXEC);
739 file = anon_inode_getfile("gpio-linehandle",
742 O_RDONLY | O_CLOEXEC);
745 goto out_put_unused_fd;
749 if (copy_to_user(ip, &handlereq, sizeof(handlereq))) {
751 * fput() will trigger the release() callback, so do not go onto
752 * the regular error cleanup path here.
759 fd_install(fd, file);
761 dev_dbg(&gdev->dev, "registered chardev handle for %d lines\n",
769 for (i = 0; i < count; i++)
770 gpiod_free(lh->descs[i]);
774 put_device(&gdev->dev);
779 * GPIO line event management
783 * struct lineevent_state - contains the state of a userspace event
784 * @gdev: the GPIO device the event pertains to
785 * @label: consumer label used to tag descriptors
786 * @desc: the GPIO descriptor held by this event
787 * @eflags: the event flags this line was requested with
788 * @irq: the interrupt that trigger in response to events on this GPIO
789 * @wait: wait queue that handles blocking reads of events
790 * @events: KFIFO for the GPIO events
791 * @read_lock: mutex lock to protect reads from colliding with adding
792 * new events to the FIFO
793 * @timestamp: cache for the timestamp storing it between hardirq
794 * and IRQ thread, used to bring the timestamp close to the actual
797 struct lineevent_state {
798 struct gpio_device *gdev;
800 struct gpio_desc *desc;
803 wait_queue_head_t wait;
804 DECLARE_KFIFO(events, struct gpioevent_data, 16);
805 struct mutex read_lock;
809 #define GPIOEVENT_REQUEST_VALID_FLAGS \
810 (GPIOEVENT_REQUEST_RISING_EDGE | \
811 GPIOEVENT_REQUEST_FALLING_EDGE)
813 static __poll_t lineevent_poll(struct file *filep,
814 struct poll_table_struct *wait)
816 struct lineevent_state *le = filep->private_data;
819 poll_wait(filep, &le->wait, wait);
821 if (!kfifo_is_empty(&le->events))
822 events = EPOLLIN | EPOLLRDNORM;
828 static ssize_t lineevent_read(struct file *filep,
833 struct lineevent_state *le = filep->private_data;
837 if (count < sizeof(struct gpioevent_data))
841 if (kfifo_is_empty(&le->events)) {
842 if (filep->f_flags & O_NONBLOCK)
845 ret = wait_event_interruptible(le->wait,
846 !kfifo_is_empty(&le->events));
851 if (mutex_lock_interruptible(&le->read_lock))
853 ret = kfifo_to_user(&le->events, buf, count, &copied);
854 mutex_unlock(&le->read_lock);
860 * If we couldn't read anything from the fifo (a different
861 * thread might have been faster) we either return -EAGAIN if
862 * the file descriptor is non-blocking, otherwise we go back to
863 * sleep and wait for more data to arrive.
865 if (copied == 0 && (filep->f_flags & O_NONBLOCK))
868 } while (copied == 0);
873 static int lineevent_release(struct inode *inode, struct file *filep)
875 struct lineevent_state *le = filep->private_data;
876 struct gpio_device *gdev = le->gdev;
878 free_irq(le->irq, le);
879 gpiod_free(le->desc);
882 put_device(&gdev->dev);
886 static long lineevent_ioctl(struct file *filep, unsigned int cmd,
889 struct lineevent_state *le = filep->private_data;
890 void __user *ip = (void __user *)arg;
891 struct gpiohandle_data ghd;
894 * We can get the value for an event line but not set it,
895 * because it is input by definition.
897 if (cmd == GPIOHANDLE_GET_LINE_VALUES_IOCTL) {
900 memset(&ghd, 0, sizeof(ghd));
902 val = gpiod_get_value_cansleep(le->desc);
907 if (copy_to_user(ip, &ghd, sizeof(ghd)))
916 static long lineevent_ioctl_compat(struct file *filep, unsigned int cmd,
919 return lineevent_ioctl(filep, cmd, (unsigned long)compat_ptr(arg));
923 static const struct file_operations lineevent_fileops = {
924 .release = lineevent_release,
925 .read = lineevent_read,
926 .poll = lineevent_poll,
927 .owner = THIS_MODULE,
928 .llseek = noop_llseek,
929 .unlocked_ioctl = lineevent_ioctl,
931 .compat_ioctl = lineevent_ioctl_compat,
935 static irqreturn_t lineevent_irq_thread(int irq, void *p)
937 struct lineevent_state *le = p;
938 struct gpioevent_data ge;
941 /* Do not leak kernel stack to userspace */
942 memset(&ge, 0, sizeof(ge));
945 * We may be running from a nested threaded interrupt in which case
946 * we didn't get the timestamp from lineevent_irq_handler().
949 ge.timestamp = ktime_get_real_ns();
951 ge.timestamp = le->timestamp;
953 if (le->eflags & GPIOEVENT_REQUEST_RISING_EDGE
954 && le->eflags & GPIOEVENT_REQUEST_FALLING_EDGE) {
955 int level = gpiod_get_value_cansleep(le->desc);
957 /* Emit low-to-high event */
958 ge.id = GPIOEVENT_EVENT_RISING_EDGE;
960 /* Emit high-to-low event */
961 ge.id = GPIOEVENT_EVENT_FALLING_EDGE;
962 } else if (le->eflags & GPIOEVENT_REQUEST_RISING_EDGE) {
963 /* Emit low-to-high event */
964 ge.id = GPIOEVENT_EVENT_RISING_EDGE;
965 } else if (le->eflags & GPIOEVENT_REQUEST_FALLING_EDGE) {
966 /* Emit high-to-low event */
967 ge.id = GPIOEVENT_EVENT_FALLING_EDGE;
972 ret = kfifo_put(&le->events, ge);
974 wake_up_poll(&le->wait, EPOLLIN);
979 static irqreturn_t lineevent_irq_handler(int irq, void *p)
981 struct lineevent_state *le = p;
984 * Just store the timestamp in hardirq context so we get it as
985 * close in time as possible to the actual event.
987 le->timestamp = ktime_get_real_ns();
989 return IRQ_WAKE_THREAD;
992 static int lineevent_create(struct gpio_device *gdev, void __user *ip)
994 struct gpioevent_request eventreq;
995 struct lineevent_state *le;
996 struct gpio_desc *desc;
1005 if (copy_from_user(&eventreq, ip, sizeof(eventreq)))
1008 offset = eventreq.lineoffset;
1009 lflags = eventreq.handleflags;
1010 eflags = eventreq.eventflags;
1012 desc = gpiochip_get_desc(gdev->chip, offset);
1014 return PTR_ERR(desc);
1016 /* Return an error if a unknown flag is set */
1017 if ((lflags & ~GPIOHANDLE_REQUEST_VALID_FLAGS) ||
1018 (eflags & ~GPIOEVENT_REQUEST_VALID_FLAGS))
1021 /* This is just wrong: we don't look for events on output lines */
1022 if ((lflags & GPIOHANDLE_REQUEST_OUTPUT) ||
1023 (lflags & GPIOHANDLE_REQUEST_OPEN_DRAIN) ||
1024 (lflags & GPIOHANDLE_REQUEST_OPEN_SOURCE))
1027 /* Only one bias flag can be set. */
1028 if (((lflags & GPIOHANDLE_REQUEST_BIAS_DISABLE) &&
1029 (lflags & (GPIOHANDLE_REQUEST_BIAS_PULL_DOWN |
1030 GPIOHANDLE_REQUEST_BIAS_PULL_UP))) ||
1031 ((lflags & GPIOHANDLE_REQUEST_BIAS_PULL_DOWN) &&
1032 (lflags & GPIOHANDLE_REQUEST_BIAS_PULL_UP)))
1035 le = kzalloc(sizeof(*le), GFP_KERNEL);
1039 get_device(&gdev->dev);
1041 /* Make sure this is terminated */
1042 eventreq.consumer_label[sizeof(eventreq.consumer_label)-1] = '\0';
1043 if (strlen(eventreq.consumer_label)) {
1044 le->label = kstrdup(eventreq.consumer_label,
1052 ret = gpiod_request(desc, le->label);
1054 goto out_free_label;
1056 le->eflags = eflags;
1058 if (lflags & GPIOHANDLE_REQUEST_ACTIVE_LOW)
1059 set_bit(FLAG_ACTIVE_LOW, &desc->flags);
1060 if (lflags & GPIOHANDLE_REQUEST_BIAS_DISABLE)
1061 set_bit(FLAG_BIAS_DISABLE, &desc->flags);
1062 if (lflags & GPIOHANDLE_REQUEST_BIAS_PULL_DOWN)
1063 set_bit(FLAG_PULL_DOWN, &desc->flags);
1064 if (lflags & GPIOHANDLE_REQUEST_BIAS_PULL_UP)
1065 set_bit(FLAG_PULL_UP, &desc->flags);
1067 ret = gpiod_direction_input(desc);
1071 le->irq = gpiod_to_irq(desc);
1077 if (eflags & GPIOEVENT_REQUEST_RISING_EDGE)
1078 irqflags |= test_bit(FLAG_ACTIVE_LOW, &desc->flags) ?
1079 IRQF_TRIGGER_FALLING : IRQF_TRIGGER_RISING;
1080 if (eflags & GPIOEVENT_REQUEST_FALLING_EDGE)
1081 irqflags |= test_bit(FLAG_ACTIVE_LOW, &desc->flags) ?
1082 IRQF_TRIGGER_RISING : IRQF_TRIGGER_FALLING;
1083 irqflags |= IRQF_ONESHOT;
1085 INIT_KFIFO(le->events);
1086 init_waitqueue_head(&le->wait);
1087 mutex_init(&le->read_lock);
1089 /* Request a thread to read the events */
1090 ret = request_threaded_irq(le->irq,
1091 lineevent_irq_handler,
1092 lineevent_irq_thread,
1099 fd = get_unused_fd_flags(O_RDONLY | O_CLOEXEC);
1105 file = anon_inode_getfile("gpio-event",
1108 O_RDONLY | O_CLOEXEC);
1110 ret = PTR_ERR(file);
1111 goto out_put_unused_fd;
1115 if (copy_to_user(ip, &eventreq, sizeof(eventreq))) {
1117 * fput() will trigger the release() callback, so do not go onto
1118 * the regular error cleanup path here.
1125 fd_install(fd, file);
1132 free_irq(le->irq, le);
1134 gpiod_free(le->desc);
1139 put_device(&gdev->dev);
1144 * gpio_ioctl() - ioctl handler for the GPIO chardev
1146 static long gpio_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
1148 struct gpio_device *gdev = filp->private_data;
1149 struct gpio_chip *chip = gdev->chip;
1150 void __user *ip = (void __user *)arg;
1152 /* We fail any subsequent ioctl():s when the chip is gone */
1156 /* Fill in the struct and pass to userspace */
1157 if (cmd == GPIO_GET_CHIPINFO_IOCTL) {
1158 struct gpiochip_info chipinfo;
1160 memset(&chipinfo, 0, sizeof(chipinfo));
1162 strncpy(chipinfo.name, dev_name(&gdev->dev),
1163 sizeof(chipinfo.name));
1164 chipinfo.name[sizeof(chipinfo.name)-1] = '\0';
1165 strncpy(chipinfo.label, gdev->label,
1166 sizeof(chipinfo.label));
1167 chipinfo.label[sizeof(chipinfo.label)-1] = '\0';
1168 chipinfo.lines = gdev->ngpio;
1169 if (copy_to_user(ip, &chipinfo, sizeof(chipinfo)))
1172 } else if (cmd == GPIO_GET_LINEINFO_IOCTL) {
1173 struct gpioline_info lineinfo;
1174 struct gpio_desc *desc;
1176 if (copy_from_user(&lineinfo, ip, sizeof(lineinfo)))
1179 desc = gpiochip_get_desc(chip, lineinfo.line_offset);
1181 return PTR_ERR(desc);
1184 strncpy(lineinfo.name, desc->name,
1185 sizeof(lineinfo.name));
1186 lineinfo.name[sizeof(lineinfo.name)-1] = '\0';
1188 lineinfo.name[0] = '\0';
1191 strncpy(lineinfo.consumer, desc->label,
1192 sizeof(lineinfo.consumer));
1193 lineinfo.consumer[sizeof(lineinfo.consumer)-1] = '\0';
1195 lineinfo.consumer[0] = '\0';
1199 * Userspace only need to know that the kernel is using
1200 * this GPIO so it can't use it.
1203 if (test_bit(FLAG_REQUESTED, &desc->flags) ||
1204 test_bit(FLAG_IS_HOGGED, &desc->flags) ||
1205 test_bit(FLAG_USED_AS_IRQ, &desc->flags) ||
1206 test_bit(FLAG_EXPORT, &desc->flags) ||
1207 test_bit(FLAG_SYSFS, &desc->flags) ||
1208 !pinctrl_gpio_can_use_line(chip->base + lineinfo.line_offset))
1209 lineinfo.flags |= GPIOLINE_FLAG_KERNEL;
1210 if (test_bit(FLAG_IS_OUT, &desc->flags))
1211 lineinfo.flags |= GPIOLINE_FLAG_IS_OUT;
1212 if (test_bit(FLAG_ACTIVE_LOW, &desc->flags))
1213 lineinfo.flags |= GPIOLINE_FLAG_ACTIVE_LOW;
1214 if (test_bit(FLAG_OPEN_DRAIN, &desc->flags))
1215 lineinfo.flags |= (GPIOLINE_FLAG_OPEN_DRAIN |
1216 GPIOLINE_FLAG_IS_OUT);
1217 if (test_bit(FLAG_OPEN_SOURCE, &desc->flags))
1218 lineinfo.flags |= (GPIOLINE_FLAG_OPEN_SOURCE |
1219 GPIOLINE_FLAG_IS_OUT);
1220 if (test_bit(FLAG_BIAS_DISABLE, &desc->flags))
1221 lineinfo.flags |= GPIOLINE_FLAG_BIAS_DISABLE;
1222 if (test_bit(FLAG_PULL_DOWN, &desc->flags))
1223 lineinfo.flags |= GPIOLINE_FLAG_BIAS_PULL_DOWN;
1224 if (test_bit(FLAG_PULL_UP, &desc->flags))
1225 lineinfo.flags |= GPIOLINE_FLAG_BIAS_PULL_UP;
1227 if (copy_to_user(ip, &lineinfo, sizeof(lineinfo)))
1230 } else if (cmd == GPIO_GET_LINEHANDLE_IOCTL) {
1231 return linehandle_create(gdev, ip);
1232 } else if (cmd == GPIO_GET_LINEEVENT_IOCTL) {
1233 return lineevent_create(gdev, ip);
1238 #ifdef CONFIG_COMPAT
1239 static long gpio_ioctl_compat(struct file *filp, unsigned int cmd,
1242 return gpio_ioctl(filp, cmd, (unsigned long)compat_ptr(arg));
1247 * gpio_chrdev_open() - open the chardev for ioctl operations
1248 * @inode: inode for this chardev
1249 * @filp: file struct for storing private data
1250 * Returns 0 on success
1252 static int gpio_chrdev_open(struct inode *inode, struct file *filp)
1254 struct gpio_device *gdev = container_of(inode->i_cdev,
1255 struct gpio_device, chrdev);
1257 /* Fail on open if the backing gpiochip is gone */
1260 get_device(&gdev->dev);
1261 filp->private_data = gdev;
1263 return nonseekable_open(inode, filp);
1267 * gpio_chrdev_release() - close chardev after ioctl operations
1268 * @inode: inode for this chardev
1269 * @filp: file struct for storing private data
1270 * Returns 0 on success
1272 static int gpio_chrdev_release(struct inode *inode, struct file *filp)
1274 struct gpio_device *gdev = container_of(inode->i_cdev,
1275 struct gpio_device, chrdev);
1277 put_device(&gdev->dev);
1282 static const struct file_operations gpio_fileops = {
1283 .release = gpio_chrdev_release,
1284 .open = gpio_chrdev_open,
1285 .owner = THIS_MODULE,
1286 .llseek = no_llseek,
1287 .unlocked_ioctl = gpio_ioctl,
1288 #ifdef CONFIG_COMPAT
1289 .compat_ioctl = gpio_ioctl_compat,
1293 static void gpiodevice_release(struct device *dev)
1295 struct gpio_device *gdev = dev_get_drvdata(dev);
1297 list_del(&gdev->list);
1298 ida_simple_remove(&gpio_ida, gdev->id);
1299 kfree_const(gdev->label);
1304 static int gpiochip_setup_dev(struct gpio_device *gdev)
1308 cdev_init(&gdev->chrdev, &gpio_fileops);
1309 gdev->chrdev.owner = THIS_MODULE;
1310 gdev->dev.devt = MKDEV(MAJOR(gpio_devt), gdev->id);
1312 ret = cdev_device_add(&gdev->chrdev, &gdev->dev);
1316 chip_dbg(gdev->chip, "added GPIO chardev (%d:%d)\n",
1317 MAJOR(gpio_devt), gdev->id);
1319 ret = gpiochip_sysfs_register(gdev);
1321 goto err_remove_device;
1323 /* From this point, the .release() function cleans up gpio_device */
1324 gdev->dev.release = gpiodevice_release;
1325 pr_debug("%s: registered GPIOs %d to %d on device: %s (%s)\n",
1326 __func__, gdev->base, gdev->base + gdev->ngpio - 1,
1327 dev_name(&gdev->dev), gdev->chip->label ? : "generic");
1332 cdev_device_del(&gdev->chrdev, &gdev->dev);
1336 static void gpiochip_machine_hog(struct gpio_chip *chip, struct gpiod_hog *hog)
1338 struct gpio_desc *desc;
1341 desc = gpiochip_get_desc(chip, hog->chip_hwnum);
1343 pr_err("%s: unable to get GPIO desc: %ld\n",
1344 __func__, PTR_ERR(desc));
1348 if (test_bit(FLAG_IS_HOGGED, &desc->flags))
1351 rv = gpiod_hog(desc, hog->line_name, hog->lflags, hog->dflags);
1353 pr_err("%s: unable to hog GPIO line (%s:%u): %d\n",
1354 __func__, chip->label, hog->chip_hwnum, rv);
1357 static void machine_gpiochip_add(struct gpio_chip *chip)
1359 struct gpiod_hog *hog;
1361 mutex_lock(&gpio_machine_hogs_mutex);
1363 list_for_each_entry(hog, &gpio_machine_hogs, list) {
1364 if (!strcmp(chip->label, hog->chip_label))
1365 gpiochip_machine_hog(chip, hog);
1368 mutex_unlock(&gpio_machine_hogs_mutex);
1371 static void gpiochip_setup_devs(void)
1373 struct gpio_device *gdev;
1376 list_for_each_entry(gdev, &gpio_devices, list) {
1377 ret = gpiochip_setup_dev(gdev);
1379 pr_err("%s: Failed to initialize gpio device (%d)\n",
1380 dev_name(&gdev->dev), ret);
1384 int gpiochip_add_data_with_key(struct gpio_chip *chip, void *data,
1385 struct lock_class_key *lock_key,
1386 struct lock_class_key *request_key)
1388 unsigned long flags;
1391 int base = chip->base;
1392 struct gpio_device *gdev;
1395 * First: allocate and populate the internal stat container, and
1396 * set up the struct device.
1398 gdev = kzalloc(sizeof(*gdev), GFP_KERNEL);
1401 gdev->dev.bus = &gpio_bus_type;
1403 chip->gpiodev = gdev;
1405 gdev->dev.parent = chip->parent;
1406 gdev->dev.of_node = chip->parent->of_node;
1409 #ifdef CONFIG_OF_GPIO
1410 /* If the gpiochip has an assigned OF node this takes precedence */
1412 gdev->dev.of_node = chip->of_node;
1414 chip->of_node = gdev->dev.of_node;
1417 gdev->id = ida_simple_get(&gpio_ida, 0, 0, GFP_KERNEL);
1422 dev_set_name(&gdev->dev, GPIOCHIP_NAME "%d", gdev->id);
1423 device_initialize(&gdev->dev);
1424 dev_set_drvdata(&gdev->dev, gdev);
1425 if (chip->parent && chip->parent->driver)
1426 gdev->owner = chip->parent->driver->owner;
1427 else if (chip->owner)
1428 /* TODO: remove chip->owner */
1429 gdev->owner = chip->owner;
1431 gdev->owner = THIS_MODULE;
1433 gdev->descs = kcalloc(chip->ngpio, sizeof(gdev->descs[0]), GFP_KERNEL);
1439 if (chip->ngpio == 0) {
1440 chip_err(chip, "tried to insert a GPIO chip with zero lines\n");
1442 goto err_free_descs;
1445 if (chip->ngpio > FASTPATH_NGPIO)
1446 chip_warn(chip, "line cnt %u is greater than fast path cnt %u\n",
1447 chip->ngpio, FASTPATH_NGPIO);
1449 gdev->label = kstrdup_const(chip->label ?: "unknown", GFP_KERNEL);
1452 goto err_free_descs;
1455 gdev->ngpio = chip->ngpio;
1458 spin_lock_irqsave(&gpio_lock, flags);
1461 * TODO: this allocates a Linux GPIO number base in the global
1462 * GPIO numberspace for this chip. In the long run we want to
1463 * get *rid* of this numberspace and use only descriptors, but
1464 * it may be a pipe dream. It will not happen before we get rid
1465 * of the sysfs interface anyways.
1468 base = gpiochip_find_base(chip->ngpio);
1471 spin_unlock_irqrestore(&gpio_lock, flags);
1472 goto err_free_label;
1475 * TODO: it should not be necessary to reflect the assigned
1476 * base outside of the GPIO subsystem. Go over drivers and
1477 * see if anyone makes use of this, else drop this and assign
1484 ret = gpiodev_add_to_list(gdev);
1486 spin_unlock_irqrestore(&gpio_lock, flags);
1487 goto err_free_label;
1490 for (i = 0; i < chip->ngpio; i++)
1491 gdev->descs[i].gdev = gdev;
1493 spin_unlock_irqrestore(&gpio_lock, flags);
1495 #ifdef CONFIG_PINCTRL
1496 INIT_LIST_HEAD(&gdev->pin_ranges);
1499 ret = gpiochip_set_desc_names(chip);
1501 goto err_remove_from_list;
1503 ret = gpiochip_alloc_valid_mask(chip);
1505 goto err_remove_from_list;
1507 ret = of_gpiochip_add(chip);
1509 goto err_free_gpiochip_mask;
1511 ret = gpiochip_init_valid_mask(chip);
1513 goto err_remove_of_chip;
1515 for (i = 0; i < chip->ngpio; i++) {
1516 struct gpio_desc *desc = &gdev->descs[i];
1518 if (chip->get_direction && gpiochip_line_is_valid(chip, i)) {
1519 assign_bit(FLAG_IS_OUT,
1520 &desc->flags, !chip->get_direction(chip, i));
1522 assign_bit(FLAG_IS_OUT,
1523 &desc->flags, !chip->direction_input);
1527 ret = gpiochip_add_pin_ranges(chip);
1529 goto err_remove_of_chip;
1531 acpi_gpiochip_add(chip);
1533 machine_gpiochip_add(chip);
1535 ret = gpiochip_irqchip_init_valid_mask(chip);
1537 goto err_remove_acpi_chip;
1539 ret = gpiochip_irqchip_init_hw(chip);
1541 goto err_remove_acpi_chip;
1543 ret = gpiochip_add_irqchip(chip, lock_key, request_key);
1545 goto err_remove_irqchip_mask;
1548 * By first adding the chardev, and then adding the device,
1549 * we get a device node entry in sysfs under
1550 * /sys/bus/gpio/devices/gpiochipN/dev that can be used for
1551 * coldplug of device nodes and other udev business.
1552 * We can do this only if gpiolib has been initialized.
1553 * Otherwise, defer until later.
1555 if (gpiolib_initialized) {
1556 ret = gpiochip_setup_dev(gdev);
1558 goto err_remove_irqchip;
1563 gpiochip_irqchip_remove(chip);
1564 err_remove_irqchip_mask:
1565 gpiochip_irqchip_free_valid_mask(chip);
1566 err_remove_acpi_chip:
1567 acpi_gpiochip_remove(chip);
1569 gpiochip_free_hogs(chip);
1570 of_gpiochip_remove(chip);
1571 err_free_gpiochip_mask:
1572 gpiochip_remove_pin_ranges(chip);
1573 gpiochip_free_valid_mask(chip);
1574 err_remove_from_list:
1575 spin_lock_irqsave(&gpio_lock, flags);
1576 list_del(&gdev->list);
1577 spin_unlock_irqrestore(&gpio_lock, flags);
1579 kfree_const(gdev->label);
1583 ida_simple_remove(&gpio_ida, gdev->id);
1585 /* failures here can mean systems won't boot... */
1586 pr_err("%s: GPIOs %d..%d (%s) failed to register, %d\n", __func__,
1587 gdev->base, gdev->base + gdev->ngpio - 1,
1588 chip->label ? : "generic", ret);
1592 EXPORT_SYMBOL_GPL(gpiochip_add_data_with_key);
1595 * gpiochip_get_data() - get per-subdriver data for the chip
1599 * The per-subdriver data for the chip.
1601 void *gpiochip_get_data(struct gpio_chip *chip)
1603 return chip->gpiodev->data;
1605 EXPORT_SYMBOL_GPL(gpiochip_get_data);
1608 * gpiochip_remove() - unregister a gpio_chip
1609 * @chip: the chip to unregister
1611 * A gpio_chip with any GPIOs still requested may not be removed.
1613 void gpiochip_remove(struct gpio_chip *chip)
1615 struct gpio_device *gdev = chip->gpiodev;
1616 struct gpio_desc *desc;
1617 unsigned long flags;
1619 bool requested = false;
1621 /* FIXME: should the legacy sysfs handling be moved to gpio_device? */
1622 gpiochip_sysfs_unregister(gdev);
1623 gpiochip_free_hogs(chip);
1624 /* Numb the device, cancelling all outstanding operations */
1626 gpiochip_irqchip_remove(chip);
1627 acpi_gpiochip_remove(chip);
1628 of_gpiochip_remove(chip);
1629 gpiochip_remove_pin_ranges(chip);
1630 gpiochip_free_valid_mask(chip);
1632 * We accept no more calls into the driver from this point, so
1633 * NULL the driver data pointer
1637 spin_lock_irqsave(&gpio_lock, flags);
1638 for (i = 0; i < gdev->ngpio; i++) {
1639 desc = &gdev->descs[i];
1640 if (test_bit(FLAG_REQUESTED, &desc->flags))
1643 spin_unlock_irqrestore(&gpio_lock, flags);
1646 dev_crit(&gdev->dev,
1647 "REMOVING GPIOCHIP WITH GPIOS STILL REQUESTED\n");
1650 * The gpiochip side puts its use of the device to rest here:
1651 * if there are no userspace clients, the chardev and device will
1652 * be removed, else it will be dangling until the last user is
1655 cdev_device_del(&gdev->chrdev, &gdev->dev);
1656 put_device(&gdev->dev);
1658 EXPORT_SYMBOL_GPL(gpiochip_remove);
1660 static void devm_gpio_chip_release(struct device *dev, void *res)
1662 struct gpio_chip *chip = *(struct gpio_chip **)res;
1664 gpiochip_remove(chip);
1668 * devm_gpiochip_add_data() - Resource managed gpiochip_add_data()
1669 * @dev: pointer to the device that gpio_chip belongs to.
1670 * @chip: the chip to register, with chip->base initialized
1671 * @data: driver-private data associated with this chip
1673 * Context: potentially before irqs will work
1675 * The gpio chip automatically be released when the device is unbound.
1678 * A negative errno if the chip can't be registered, such as because the
1679 * chip->base is invalid or already associated with a different chip.
1680 * Otherwise it returns zero as a success code.
1682 int devm_gpiochip_add_data(struct device *dev, struct gpio_chip *chip,
1685 struct gpio_chip **ptr;
1688 ptr = devres_alloc(devm_gpio_chip_release, sizeof(*ptr),
1693 ret = gpiochip_add_data(chip, data);
1700 devres_add(dev, ptr);
1704 EXPORT_SYMBOL_GPL(devm_gpiochip_add_data);
1707 * gpiochip_find() - iterator for locating a specific gpio_chip
1708 * @data: data to pass to match function
1709 * @match: Callback function to check gpio_chip
1711 * Similar to bus_find_device. It returns a reference to a gpio_chip as
1712 * determined by a user supplied @match callback. The callback should return
1713 * 0 if the device doesn't match and non-zero if it does. If the callback is
1714 * non-zero, this function will return to the caller and not iterate over any
1717 struct gpio_chip *gpiochip_find(void *data,
1718 int (*match)(struct gpio_chip *chip,
1721 struct gpio_device *gdev;
1722 struct gpio_chip *chip = NULL;
1723 unsigned long flags;
1725 spin_lock_irqsave(&gpio_lock, flags);
1726 list_for_each_entry(gdev, &gpio_devices, list)
1727 if (gdev->chip && match(gdev->chip, data)) {
1732 spin_unlock_irqrestore(&gpio_lock, flags);
1736 EXPORT_SYMBOL_GPL(gpiochip_find);
1738 static int gpiochip_match_name(struct gpio_chip *chip, void *data)
1740 const char *name = data;
1742 return !strcmp(chip->label, name);
1745 static struct gpio_chip *find_chip_by_name(const char *name)
1747 return gpiochip_find((void *)name, gpiochip_match_name);
1750 #ifdef CONFIG_GPIOLIB_IRQCHIP
1753 * The following is irqchip helper code for gpiochips.
1756 static int gpiochip_irqchip_init_hw(struct gpio_chip *gc)
1758 struct gpio_irq_chip *girq = &gc->irq;
1763 return girq->init_hw(gc);
1766 static int gpiochip_irqchip_init_valid_mask(struct gpio_chip *gc)
1768 struct gpio_irq_chip *girq = &gc->irq;
1770 if (!girq->init_valid_mask)
1773 girq->valid_mask = gpiochip_allocate_mask(gc);
1774 if (!girq->valid_mask)
1777 girq->init_valid_mask(gc, girq->valid_mask, gc->ngpio);
1782 static void gpiochip_irqchip_free_valid_mask(struct gpio_chip *gpiochip)
1784 bitmap_free(gpiochip->irq.valid_mask);
1785 gpiochip->irq.valid_mask = NULL;
1788 bool gpiochip_irqchip_irq_valid(const struct gpio_chip *gpiochip,
1789 unsigned int offset)
1791 if (!gpiochip_line_is_valid(gpiochip, offset))
1793 /* No mask means all valid */
1794 if (likely(!gpiochip->irq.valid_mask))
1796 return test_bit(offset, gpiochip->irq.valid_mask);
1798 EXPORT_SYMBOL_GPL(gpiochip_irqchip_irq_valid);
1801 * gpiochip_set_cascaded_irqchip() - connects a cascaded irqchip to a gpiochip
1802 * @gc: the gpiochip to set the irqchip chain to
1803 * @parent_irq: the irq number corresponding to the parent IRQ for this
1805 * @parent_handler: the parent interrupt handler for the accumulated IRQ
1806 * coming out of the gpiochip. If the interrupt is nested rather than
1807 * cascaded, pass NULL in this handler argument
1809 static void gpiochip_set_cascaded_irqchip(struct gpio_chip *gc,
1810 unsigned int parent_irq,
1811 irq_flow_handler_t parent_handler)
1813 struct gpio_irq_chip *girq = &gc->irq;
1814 struct device *dev = &gc->gpiodev->dev;
1816 if (!girq->domain) {
1817 chip_err(gc, "called %s before setting up irqchip\n",
1822 if (parent_handler) {
1823 if (gc->can_sleep) {
1825 "you cannot have chained interrupts on a chip that may sleep\n");
1828 girq->parents = devm_kcalloc(dev, 1,
1829 sizeof(*girq->parents),
1831 if (!girq->parents) {
1832 chip_err(gc, "out of memory allocating parent IRQ\n");
1835 girq->parents[0] = parent_irq;
1836 girq->num_parents = 1;
1838 * The parent irqchip is already using the chip_data for this
1839 * irqchip, so our callbacks simply use the handler_data.
1841 irq_set_chained_handler_and_data(parent_irq, parent_handler,
1847 * gpiochip_set_nested_irqchip() - connects a nested irqchip to a gpiochip
1848 * @gpiochip: the gpiochip to set the irqchip nested handler to
1849 * @irqchip: the irqchip to nest to the gpiochip
1850 * @parent_irq: the irq number corresponding to the parent IRQ for this
1853 void gpiochip_set_nested_irqchip(struct gpio_chip *gpiochip,
1854 struct irq_chip *irqchip,
1855 unsigned int parent_irq)
1857 gpiochip_set_cascaded_irqchip(gpiochip, parent_irq, NULL);
1859 EXPORT_SYMBOL_GPL(gpiochip_set_nested_irqchip);
1861 #ifdef CONFIG_IRQ_DOMAIN_HIERARCHY
1864 * gpiochip_set_hierarchical_irqchip() - connects a hierarchical irqchip
1866 * @gc: the gpiochip to set the irqchip hierarchical handler to
1867 * @irqchip: the irqchip to handle this level of the hierarchy, the interrupt
1868 * will then percolate up to the parent
1870 static void gpiochip_set_hierarchical_irqchip(struct gpio_chip *gc,
1871 struct irq_chip *irqchip)
1873 /* DT will deal with mapping each IRQ as we go along */
1874 if (is_of_node(gc->irq.fwnode))
1878 * This is for legacy and boardfile "irqchip" fwnodes: allocate
1879 * irqs upfront instead of dynamically since we don't have the
1880 * dynamic type of allocation that hardware description languages
1881 * provide. Once all GPIO drivers using board files are gone from
1882 * the kernel we can delete this code, but for a transitional period
1883 * it is necessary to keep this around.
1885 if (is_fwnode_irqchip(gc->irq.fwnode)) {
1889 for (i = 0; i < gc->ngpio; i++) {
1890 struct irq_fwspec fwspec;
1891 unsigned int parent_hwirq;
1892 unsigned int parent_type;
1893 struct gpio_irq_chip *girq = &gc->irq;
1896 * We call the child to parent translation function
1897 * only to check if the child IRQ is valid or not.
1898 * Just pick the rising edge type here as that is what
1899 * we likely need to support.
1901 ret = girq->child_to_parent_hwirq(gc, i,
1902 IRQ_TYPE_EDGE_RISING,
1906 chip_err(gc, "skip set-up on hwirq %d\n",
1911 fwspec.fwnode = gc->irq.fwnode;
1912 /* This is the hwirq for the GPIO line side of things */
1913 fwspec.param[0] = girq->child_offset_to_irq(gc, i);
1914 /* Just pick something */
1915 fwspec.param[1] = IRQ_TYPE_EDGE_RISING;
1916 fwspec.param_count = 2;
1917 ret = __irq_domain_alloc_irqs(gc->irq.domain,
1918 /* just pick something */
1927 "can not allocate irq for GPIO line %d parent hwirq %d in hierarchy domain: %d\n",
1934 chip_err(gc, "%s unknown fwnode type proceed anyway\n", __func__);
1939 static int gpiochip_hierarchy_irq_domain_translate(struct irq_domain *d,
1940 struct irq_fwspec *fwspec,
1941 unsigned long *hwirq,
1944 /* We support standard DT translation */
1945 if (is_of_node(fwspec->fwnode) && fwspec->param_count == 2) {
1946 return irq_domain_translate_twocell(d, fwspec, hwirq, type);
1949 /* This is for board files and others not using DT */
1950 if (is_fwnode_irqchip(fwspec->fwnode)) {
1953 ret = irq_domain_translate_twocell(d, fwspec, hwirq, type);
1956 WARN_ON(*type == IRQ_TYPE_NONE);
1962 static int gpiochip_hierarchy_irq_domain_alloc(struct irq_domain *d,
1964 unsigned int nr_irqs,
1967 struct gpio_chip *gc = d->host_data;
1968 irq_hw_number_t hwirq;
1969 unsigned int type = IRQ_TYPE_NONE;
1970 struct irq_fwspec *fwspec = data;
1972 unsigned int parent_hwirq;
1973 unsigned int parent_type;
1974 struct gpio_irq_chip *girq = &gc->irq;
1978 * The nr_irqs parameter is always one except for PCI multi-MSI
1979 * so this should not happen.
1981 WARN_ON(nr_irqs != 1);
1983 ret = gc->irq.child_irq_domain_ops.translate(d, fwspec, &hwirq, &type);
1987 chip_dbg(gc, "allocate IRQ %d, hwirq %lu\n", irq, hwirq);
1989 ret = girq->child_to_parent_hwirq(gc, hwirq, type,
1990 &parent_hwirq, &parent_type);
1992 chip_err(gc, "can't look up hwirq %lu\n", hwirq);
1995 chip_dbg(gc, "found parent hwirq %u\n", parent_hwirq);
1998 * We set handle_bad_irq because the .set_type() should
1999 * always be invoked and set the right type of handler.
2001 irq_domain_set_info(d,
2010 /* This parent only handles asserted level IRQs */
2011 parent_arg = girq->populate_parent_alloc_arg(gc, parent_hwirq, parent_type);
2015 chip_dbg(gc, "alloc_irqs_parent for %d parent hwirq %d\n",
2017 irq_set_lockdep_class(irq, gc->irq.lock_key, gc->irq.request_key);
2018 ret = irq_domain_alloc_irqs_parent(d, irq, 1, parent_arg);
2020 * If the parent irqdomain is msi, the interrupts have already
2021 * been allocated, so the EEXIST is good.
2023 if (irq_domain_is_msi(d->parent) && (ret == -EEXIST))
2027 "failed to allocate parent hwirq %d for hwirq %lu\n",
2028 parent_hwirq, hwirq);
2034 static unsigned int gpiochip_child_offset_to_irq_noop(struct gpio_chip *chip,
2035 unsigned int offset)
2040 static void gpiochip_hierarchy_setup_domain_ops(struct irq_domain_ops *ops)
2042 ops->activate = gpiochip_irq_domain_activate;
2043 ops->deactivate = gpiochip_irq_domain_deactivate;
2044 ops->alloc = gpiochip_hierarchy_irq_domain_alloc;
2045 ops->free = irq_domain_free_irqs_common;
2048 * We only allow overriding the translate() function for
2049 * hierarchical chips, and this should only be done if the user
2050 * really need something other than 1:1 translation.
2052 if (!ops->translate)
2053 ops->translate = gpiochip_hierarchy_irq_domain_translate;
2056 static int gpiochip_hierarchy_add_domain(struct gpio_chip *gc)
2058 if (!gc->irq.child_to_parent_hwirq ||
2060 chip_err(gc, "missing irqdomain vital data\n");
2064 if (!gc->irq.child_offset_to_irq)
2065 gc->irq.child_offset_to_irq = gpiochip_child_offset_to_irq_noop;
2067 if (!gc->irq.populate_parent_alloc_arg)
2068 gc->irq.populate_parent_alloc_arg =
2069 gpiochip_populate_parent_fwspec_twocell;
2071 gpiochip_hierarchy_setup_domain_ops(&gc->irq.child_irq_domain_ops);
2073 gc->irq.domain = irq_domain_create_hierarchy(
2074 gc->irq.parent_domain,
2078 &gc->irq.child_irq_domain_ops,
2081 if (!gc->irq.domain)
2084 gpiochip_set_hierarchical_irqchip(gc, gc->irq.chip);
2089 static bool gpiochip_hierarchy_is_hierarchical(struct gpio_chip *gc)
2091 return !!gc->irq.parent_domain;
2094 void *gpiochip_populate_parent_fwspec_twocell(struct gpio_chip *chip,
2095 unsigned int parent_hwirq,
2096 unsigned int parent_type)
2098 struct irq_fwspec *fwspec;
2100 fwspec = kmalloc(sizeof(*fwspec), GFP_KERNEL);
2104 fwspec->fwnode = chip->irq.parent_domain->fwnode;
2105 fwspec->param_count = 2;
2106 fwspec->param[0] = parent_hwirq;
2107 fwspec->param[1] = parent_type;
2111 EXPORT_SYMBOL_GPL(gpiochip_populate_parent_fwspec_twocell);
2113 void *gpiochip_populate_parent_fwspec_fourcell(struct gpio_chip *chip,
2114 unsigned int parent_hwirq,
2115 unsigned int parent_type)
2117 struct irq_fwspec *fwspec;
2119 fwspec = kmalloc(sizeof(*fwspec), GFP_KERNEL);
2123 fwspec->fwnode = chip->irq.parent_domain->fwnode;
2124 fwspec->param_count = 4;
2125 fwspec->param[0] = 0;
2126 fwspec->param[1] = parent_hwirq;
2127 fwspec->param[2] = 0;
2128 fwspec->param[3] = parent_type;
2132 EXPORT_SYMBOL_GPL(gpiochip_populate_parent_fwspec_fourcell);
2136 static int gpiochip_hierarchy_add_domain(struct gpio_chip *gc)
2141 static bool gpiochip_hierarchy_is_hierarchical(struct gpio_chip *gc)
2146 #endif /* CONFIG_IRQ_DOMAIN_HIERARCHY */
2149 * gpiochip_irq_map() - maps an IRQ into a GPIO irqchip
2150 * @d: the irqdomain used by this irqchip
2151 * @irq: the global irq number used by this GPIO irqchip irq
2152 * @hwirq: the local IRQ/GPIO line offset on this gpiochip
2154 * This function will set up the mapping for a certain IRQ line on a
2155 * gpiochip by assigning the gpiochip as chip data, and using the irqchip
2156 * stored inside the gpiochip.
2158 int gpiochip_irq_map(struct irq_domain *d, unsigned int irq,
2159 irq_hw_number_t hwirq)
2161 struct gpio_chip *chip = d->host_data;
2164 if (!gpiochip_irqchip_irq_valid(chip, hwirq))
2167 irq_set_chip_data(irq, chip);
2169 * This lock class tells lockdep that GPIO irqs are in a different
2170 * category than their parents, so it won't report false recursion.
2172 irq_set_lockdep_class(irq, chip->irq.lock_key, chip->irq.request_key);
2173 irq_set_chip_and_handler(irq, chip->irq.chip, chip->irq.handler);
2174 /* Chips that use nested thread handlers have them marked */
2175 if (chip->irq.threaded)
2176 irq_set_nested_thread(irq, 1);
2177 irq_set_noprobe(irq);
2179 if (chip->irq.num_parents == 1)
2180 ret = irq_set_parent(irq, chip->irq.parents[0]);
2181 else if (chip->irq.map)
2182 ret = irq_set_parent(irq, chip->irq.map[hwirq]);
2188 * No set-up of the hardware will happen if IRQ_TYPE_NONE
2189 * is passed as default type.
2191 if (chip->irq.default_type != IRQ_TYPE_NONE)
2192 irq_set_irq_type(irq, chip->irq.default_type);
2196 EXPORT_SYMBOL_GPL(gpiochip_irq_map);
2198 void gpiochip_irq_unmap(struct irq_domain *d, unsigned int irq)
2200 struct gpio_chip *chip = d->host_data;
2202 if (chip->irq.threaded)
2203 irq_set_nested_thread(irq, 0);
2204 irq_set_chip_and_handler(irq, NULL, NULL);
2205 irq_set_chip_data(irq, NULL);
2207 EXPORT_SYMBOL_GPL(gpiochip_irq_unmap);
2209 static const struct irq_domain_ops gpiochip_domain_ops = {
2210 .map = gpiochip_irq_map,
2211 .unmap = gpiochip_irq_unmap,
2212 /* Virtually all GPIO irqchips are twocell:ed */
2213 .xlate = irq_domain_xlate_twocell,
2217 * TODO: move these activate/deactivate in under the hierarchicial
2218 * irqchip implementation as static once SPMI and SSBI (all external
2219 * users) are phased over.
2222 * gpiochip_irq_domain_activate() - Lock a GPIO to be used as an IRQ
2223 * @domain: The IRQ domain used by this IRQ chip
2224 * @data: Outermost irq_data associated with the IRQ
2225 * @reserve: If set, only reserve an interrupt vector instead of assigning one
2227 * This function is a wrapper that calls gpiochip_lock_as_irq() and is to be
2228 * used as the activate function for the &struct irq_domain_ops. The host_data
2229 * for the IRQ domain must be the &struct gpio_chip.
2231 int gpiochip_irq_domain_activate(struct irq_domain *domain,
2232 struct irq_data *data, bool reserve)
2234 struct gpio_chip *chip = domain->host_data;
2236 return gpiochip_lock_as_irq(chip, data->hwirq);
2238 EXPORT_SYMBOL_GPL(gpiochip_irq_domain_activate);
2241 * gpiochip_irq_domain_deactivate() - Unlock a GPIO used as an IRQ
2242 * @domain: The IRQ domain used by this IRQ chip
2243 * @data: Outermost irq_data associated with the IRQ
2245 * This function is a wrapper that will call gpiochip_unlock_as_irq() and is to
2246 * be used as the deactivate function for the &struct irq_domain_ops. The
2247 * host_data for the IRQ domain must be the &struct gpio_chip.
2249 void gpiochip_irq_domain_deactivate(struct irq_domain *domain,
2250 struct irq_data *data)
2252 struct gpio_chip *chip = domain->host_data;
2254 return gpiochip_unlock_as_irq(chip, data->hwirq);
2256 EXPORT_SYMBOL_GPL(gpiochip_irq_domain_deactivate);
2258 static int gpiochip_to_irq(struct gpio_chip *chip, unsigned offset)
2260 struct irq_domain *domain = chip->irq.domain;
2262 if (!gpiochip_irqchip_irq_valid(chip, offset))
2265 #ifdef CONFIG_IRQ_DOMAIN_HIERARCHY
2266 if (irq_domain_is_hierarchy(domain)) {
2267 struct irq_fwspec spec;
2269 spec.fwnode = domain->fwnode;
2270 spec.param_count = 2;
2271 spec.param[0] = chip->irq.child_offset_to_irq(chip, offset);
2272 spec.param[1] = IRQ_TYPE_NONE;
2274 return irq_create_fwspec_mapping(&spec);
2278 return irq_create_mapping(domain, offset);
2281 static int gpiochip_irq_reqres(struct irq_data *d)
2283 struct gpio_chip *chip = irq_data_get_irq_chip_data(d);
2285 return gpiochip_reqres_irq(chip, d->hwirq);
2288 static void gpiochip_irq_relres(struct irq_data *d)
2290 struct gpio_chip *chip = irq_data_get_irq_chip_data(d);
2292 gpiochip_relres_irq(chip, d->hwirq);
2295 static void gpiochip_irq_enable(struct irq_data *d)
2297 struct gpio_chip *chip = irq_data_get_irq_chip_data(d);
2299 gpiochip_enable_irq(chip, d->hwirq);
2300 if (chip->irq.irq_enable)
2301 chip->irq.irq_enable(d);
2303 chip->irq.chip->irq_unmask(d);
2306 static void gpiochip_irq_disable(struct irq_data *d)
2308 struct gpio_chip *chip = irq_data_get_irq_chip_data(d);
2311 * Since we override .irq_disable() we need to mimic the
2312 * behaviour of __irq_disable() in irq/chip.c.
2313 * First call .irq_disable() if it exists, else mimic the
2314 * behaviour of mask_irq() which calls .irq_mask() if
2317 if (chip->irq.irq_disable)
2318 chip->irq.irq_disable(d);
2319 else if (chip->irq.chip->irq_mask)
2320 chip->irq.chip->irq_mask(d);
2321 gpiochip_disable_irq(chip, d->hwirq);
2324 static void gpiochip_set_irq_hooks(struct gpio_chip *gpiochip)
2326 struct irq_chip *irqchip = gpiochip->irq.chip;
2328 if (!irqchip->irq_request_resources &&
2329 !irqchip->irq_release_resources) {
2330 irqchip->irq_request_resources = gpiochip_irq_reqres;
2331 irqchip->irq_release_resources = gpiochip_irq_relres;
2333 if (WARN_ON(gpiochip->irq.irq_enable))
2335 /* Check if the irqchip already has this hook... */
2336 if (irqchip->irq_enable == gpiochip_irq_enable) {
2338 * ...and if so, give a gentle warning that this is bad
2342 "detected irqchip that is shared with multiple gpiochips: please fix the driver.\n");
2345 gpiochip->irq.irq_enable = irqchip->irq_enable;
2346 gpiochip->irq.irq_disable = irqchip->irq_disable;
2347 irqchip->irq_enable = gpiochip_irq_enable;
2348 irqchip->irq_disable = gpiochip_irq_disable;
2352 * gpiochip_add_irqchip() - adds an IRQ chip to a GPIO chip
2353 * @gpiochip: the GPIO chip to add the IRQ chip to
2354 * @lock_key: lockdep class for IRQ lock
2355 * @request_key: lockdep class for IRQ request
2357 static int gpiochip_add_irqchip(struct gpio_chip *gpiochip,
2358 struct lock_class_key *lock_key,
2359 struct lock_class_key *request_key)
2361 struct irq_chip *irqchip = gpiochip->irq.chip;
2362 const struct irq_domain_ops *ops = NULL;
2363 struct device_node *np;
2370 if (gpiochip->irq.parent_handler && gpiochip->can_sleep) {
2371 chip_err(gpiochip, "you cannot have chained interrupts on a chip that may sleep\n");
2375 np = gpiochip->gpiodev->dev.of_node;
2376 type = gpiochip->irq.default_type;
2379 * Specifying a default trigger is a terrible idea if DT or ACPI is
2380 * used to configure the interrupts, as you may end up with
2381 * conflicting triggers. Tell the user, and reset to NONE.
2383 if (WARN(np && type != IRQ_TYPE_NONE,
2384 "%s: Ignoring %u default trigger\n", np->full_name, type))
2385 type = IRQ_TYPE_NONE;
2387 if (has_acpi_companion(gpiochip->parent) && type != IRQ_TYPE_NONE) {
2388 acpi_handle_warn(ACPI_HANDLE(gpiochip->parent),
2389 "Ignoring %u default trigger\n", type);
2390 type = IRQ_TYPE_NONE;
2393 gpiochip->to_irq = gpiochip_to_irq;
2394 gpiochip->irq.default_type = type;
2395 gpiochip->irq.lock_key = lock_key;
2396 gpiochip->irq.request_key = request_key;
2398 /* If a parent irqdomain is provided, let's build a hierarchy */
2399 if (gpiochip_hierarchy_is_hierarchical(gpiochip)) {
2400 int ret = gpiochip_hierarchy_add_domain(gpiochip);
2404 /* Some drivers provide custom irqdomain ops */
2405 if (gpiochip->irq.domain_ops)
2406 ops = gpiochip->irq.domain_ops;
2409 ops = &gpiochip_domain_ops;
2410 gpiochip->irq.domain = irq_domain_add_simple(np,
2412 gpiochip->irq.first,
2414 if (!gpiochip->irq.domain)
2418 if (gpiochip->irq.parent_handler) {
2419 void *data = gpiochip->irq.parent_handler_data ?: gpiochip;
2421 for (i = 0; i < gpiochip->irq.num_parents; i++) {
2423 * The parent IRQ chip is already using the chip_data
2424 * for this IRQ chip, so our callbacks simply use the
2427 irq_set_chained_handler_and_data(gpiochip->irq.parents[i],
2428 gpiochip->irq.parent_handler,
2433 gpiochip_set_irq_hooks(gpiochip);
2435 acpi_gpiochip_request_interrupts(gpiochip);
2441 * gpiochip_irqchip_remove() - removes an irqchip added to a gpiochip
2442 * @gpiochip: the gpiochip to remove the irqchip from
2444 * This is called only from gpiochip_remove()
2446 static void gpiochip_irqchip_remove(struct gpio_chip *gpiochip)
2448 struct irq_chip *irqchip = gpiochip->irq.chip;
2449 unsigned int offset;
2451 acpi_gpiochip_free_interrupts(gpiochip);
2453 if (irqchip && gpiochip->irq.parent_handler) {
2454 struct gpio_irq_chip *irq = &gpiochip->irq;
2457 for (i = 0; i < irq->num_parents; i++)
2458 irq_set_chained_handler_and_data(irq->parents[i],
2462 /* Remove all IRQ mappings and delete the domain */
2463 if (gpiochip->irq.domain) {
2466 for (offset = 0; offset < gpiochip->ngpio; offset++) {
2467 if (!gpiochip_irqchip_irq_valid(gpiochip, offset))
2470 irq = irq_find_mapping(gpiochip->irq.domain, offset);
2471 irq_dispose_mapping(irq);
2474 irq_domain_remove(gpiochip->irq.domain);
2478 if (irqchip->irq_request_resources == gpiochip_irq_reqres) {
2479 irqchip->irq_request_resources = NULL;
2480 irqchip->irq_release_resources = NULL;
2482 if (irqchip->irq_enable == gpiochip_irq_enable) {
2483 irqchip->irq_enable = gpiochip->irq.irq_enable;
2484 irqchip->irq_disable = gpiochip->irq.irq_disable;
2487 gpiochip->irq.irq_enable = NULL;
2488 gpiochip->irq.irq_disable = NULL;
2489 gpiochip->irq.chip = NULL;
2491 gpiochip_irqchip_free_valid_mask(gpiochip);
2495 * gpiochip_irqchip_add_key() - adds an irqchip to a gpiochip
2496 * @gpiochip: the gpiochip to add the irqchip to
2497 * @irqchip: the irqchip to add to the gpiochip
2498 * @first_irq: if not dynamically assigned, the base (first) IRQ to
2499 * allocate gpiochip irqs from
2500 * @handler: the irq handler to use (often a predefined irq core function)
2501 * @type: the default type for IRQs on this irqchip, pass IRQ_TYPE_NONE
2502 * to have the core avoid setting up any default type in the hardware.
2503 * @threaded: whether this irqchip uses a nested thread handler
2504 * @lock_key: lockdep class for IRQ lock
2505 * @request_key: lockdep class for IRQ request
2507 * This function closely associates a certain irqchip with a certain
2508 * gpiochip, providing an irq domain to translate the local IRQs to
2509 * global irqs in the gpiolib core, and making sure that the gpiochip
2510 * is passed as chip data to all related functions. Driver callbacks
2511 * need to use gpiochip_get_data() to get their local state containers back
2512 * from the gpiochip passed as chip data. An irqdomain will be stored
2513 * in the gpiochip that shall be used by the driver to handle IRQ number
2514 * translation. The gpiochip will need to be initialized and registered
2515 * before calling this function.
2517 * This function will handle two cell:ed simple IRQs and assumes all
2518 * the pins on the gpiochip can generate a unique IRQ. Everything else
2519 * need to be open coded.
2521 int gpiochip_irqchip_add_key(struct gpio_chip *gpiochip,
2522 struct irq_chip *irqchip,
2523 unsigned int first_irq,
2524 irq_flow_handler_t handler,
2527 struct lock_class_key *lock_key,
2528 struct lock_class_key *request_key)
2530 struct device_node *of_node;
2532 if (!gpiochip || !irqchip)
2535 if (!gpiochip->parent) {
2536 pr_err("missing gpiochip .dev parent pointer\n");
2539 gpiochip->irq.threaded = threaded;
2540 of_node = gpiochip->parent->of_node;
2541 #ifdef CONFIG_OF_GPIO
2543 * If the gpiochip has an assigned OF node this takes precedence
2544 * FIXME: get rid of this and use gpiochip->parent->of_node
2547 if (gpiochip->of_node)
2548 of_node = gpiochip->of_node;
2551 * Specifying a default trigger is a terrible idea if DT or ACPI is
2552 * used to configure the interrupts, as you may end-up with
2553 * conflicting triggers. Tell the user, and reset to NONE.
2555 if (WARN(of_node && type != IRQ_TYPE_NONE,
2556 "%pOF: Ignoring %d default trigger\n", of_node, type))
2557 type = IRQ_TYPE_NONE;
2558 if (has_acpi_companion(gpiochip->parent) && type != IRQ_TYPE_NONE) {
2559 acpi_handle_warn(ACPI_HANDLE(gpiochip->parent),
2560 "Ignoring %d default trigger\n", type);
2561 type = IRQ_TYPE_NONE;
2564 gpiochip->irq.chip = irqchip;
2565 gpiochip->irq.handler = handler;
2566 gpiochip->irq.default_type = type;
2567 gpiochip->to_irq = gpiochip_to_irq;
2568 gpiochip->irq.lock_key = lock_key;
2569 gpiochip->irq.request_key = request_key;
2570 gpiochip->irq.domain = irq_domain_add_simple(of_node,
2571 gpiochip->ngpio, first_irq,
2572 &gpiochip_domain_ops, gpiochip);
2573 if (!gpiochip->irq.domain) {
2574 gpiochip->irq.chip = NULL;
2578 gpiochip_set_irq_hooks(gpiochip);
2580 acpi_gpiochip_request_interrupts(gpiochip);
2584 EXPORT_SYMBOL_GPL(gpiochip_irqchip_add_key);
2586 #else /* CONFIG_GPIOLIB_IRQCHIP */
2588 static inline int gpiochip_add_irqchip(struct gpio_chip *gpiochip,
2589 struct lock_class_key *lock_key,
2590 struct lock_class_key *request_key)
2594 static void gpiochip_irqchip_remove(struct gpio_chip *gpiochip) {}
2596 static inline int gpiochip_irqchip_init_hw(struct gpio_chip *gpiochip)
2601 static inline int gpiochip_irqchip_init_valid_mask(struct gpio_chip *gpiochip)
2605 static inline void gpiochip_irqchip_free_valid_mask(struct gpio_chip *gpiochip)
2608 #endif /* CONFIG_GPIOLIB_IRQCHIP */
2611 * gpiochip_generic_request() - request the gpio function for a pin
2612 * @chip: the gpiochip owning the GPIO
2613 * @offset: the offset of the GPIO to request for GPIO function
2615 int gpiochip_generic_request(struct gpio_chip *chip, unsigned offset)
2617 return pinctrl_gpio_request(chip->gpiodev->base + offset);
2619 EXPORT_SYMBOL_GPL(gpiochip_generic_request);
2622 * gpiochip_generic_free() - free the gpio function from a pin
2623 * @chip: the gpiochip to request the gpio function for
2624 * @offset: the offset of the GPIO to free from GPIO function
2626 void gpiochip_generic_free(struct gpio_chip *chip, unsigned offset)
2628 pinctrl_gpio_free(chip->gpiodev->base + offset);
2630 EXPORT_SYMBOL_GPL(gpiochip_generic_free);
2633 * gpiochip_generic_config() - apply configuration for a pin
2634 * @chip: the gpiochip owning the GPIO
2635 * @offset: the offset of the GPIO to apply the configuration
2636 * @config: the configuration to be applied
2638 int gpiochip_generic_config(struct gpio_chip *chip, unsigned offset,
2639 unsigned long config)
2641 return pinctrl_gpio_set_config(chip->gpiodev->base + offset, config);
2643 EXPORT_SYMBOL_GPL(gpiochip_generic_config);
2645 #ifdef CONFIG_PINCTRL
2648 * gpiochip_add_pingroup_range() - add a range for GPIO <-> pin mapping
2649 * @chip: the gpiochip to add the range for
2650 * @pctldev: the pin controller to map to
2651 * @gpio_offset: the start offset in the current gpio_chip number space
2652 * @pin_group: name of the pin group inside the pin controller
2654 * Calling this function directly from a DeviceTree-supported
2655 * pinctrl driver is DEPRECATED. Please see Section 2.1 of
2656 * Documentation/devicetree/bindings/gpio/gpio.txt on how to
2657 * bind pinctrl and gpio drivers via the "gpio-ranges" property.
2659 int gpiochip_add_pingroup_range(struct gpio_chip *chip,
2660 struct pinctrl_dev *pctldev,
2661 unsigned int gpio_offset, const char *pin_group)
2663 struct gpio_pin_range *pin_range;
2664 struct gpio_device *gdev = chip->gpiodev;
2667 pin_range = kzalloc(sizeof(*pin_range), GFP_KERNEL);
2669 chip_err(chip, "failed to allocate pin ranges\n");
2673 /* Use local offset as range ID */
2674 pin_range->range.id = gpio_offset;
2675 pin_range->range.gc = chip;
2676 pin_range->range.name = chip->label;
2677 pin_range->range.base = gdev->base + gpio_offset;
2678 pin_range->pctldev = pctldev;
2680 ret = pinctrl_get_group_pins(pctldev, pin_group,
2681 &pin_range->range.pins,
2682 &pin_range->range.npins);
2688 pinctrl_add_gpio_range(pctldev, &pin_range->range);
2690 chip_dbg(chip, "created GPIO range %d->%d ==> %s PINGRP %s\n",
2691 gpio_offset, gpio_offset + pin_range->range.npins - 1,
2692 pinctrl_dev_get_devname(pctldev), pin_group);
2694 list_add_tail(&pin_range->node, &gdev->pin_ranges);
2698 EXPORT_SYMBOL_GPL(gpiochip_add_pingroup_range);
2701 * gpiochip_add_pin_range() - add a range for GPIO <-> pin mapping
2702 * @chip: the gpiochip to add the range for
2703 * @pinctl_name: the dev_name() of the pin controller to map to
2704 * @gpio_offset: the start offset in the current gpio_chip number space
2705 * @pin_offset: the start offset in the pin controller number space
2706 * @npins: the number of pins from the offset of each pin space (GPIO and
2707 * pin controller) to accumulate in this range
2710 * 0 on success, or a negative error-code on failure.
2712 * Calling this function directly from a DeviceTree-supported
2713 * pinctrl driver is DEPRECATED. Please see Section 2.1 of
2714 * Documentation/devicetree/bindings/gpio/gpio.txt on how to
2715 * bind pinctrl and gpio drivers via the "gpio-ranges" property.
2717 int gpiochip_add_pin_range(struct gpio_chip *chip, const char *pinctl_name,
2718 unsigned int gpio_offset, unsigned int pin_offset,
2721 struct gpio_pin_range *pin_range;
2722 struct gpio_device *gdev = chip->gpiodev;
2725 pin_range = kzalloc(sizeof(*pin_range), GFP_KERNEL);
2727 chip_err(chip, "failed to allocate pin ranges\n");
2731 /* Use local offset as range ID */
2732 pin_range->range.id = gpio_offset;
2733 pin_range->range.gc = chip;
2734 pin_range->range.name = chip->label;
2735 pin_range->range.base = gdev->base + gpio_offset;
2736 pin_range->range.pin_base = pin_offset;
2737 pin_range->range.npins = npins;
2738 pin_range->pctldev = pinctrl_find_and_add_gpio_range(pinctl_name,
2740 if (IS_ERR(pin_range->pctldev)) {
2741 ret = PTR_ERR(pin_range->pctldev);
2742 chip_err(chip, "could not create pin range\n");
2746 chip_dbg(chip, "created GPIO range %d->%d ==> %s PIN %d->%d\n",
2747 gpio_offset, gpio_offset + npins - 1,
2749 pin_offset, pin_offset + npins - 1);
2751 list_add_tail(&pin_range->node, &gdev->pin_ranges);
2755 EXPORT_SYMBOL_GPL(gpiochip_add_pin_range);
2758 * gpiochip_remove_pin_ranges() - remove all the GPIO <-> pin mappings
2759 * @chip: the chip to remove all the mappings for
2761 void gpiochip_remove_pin_ranges(struct gpio_chip *chip)
2763 struct gpio_pin_range *pin_range, *tmp;
2764 struct gpio_device *gdev = chip->gpiodev;
2766 list_for_each_entry_safe(pin_range, tmp, &gdev->pin_ranges, node) {
2767 list_del(&pin_range->node);
2768 pinctrl_remove_gpio_range(pin_range->pctldev,
2773 EXPORT_SYMBOL_GPL(gpiochip_remove_pin_ranges);
2775 #endif /* CONFIG_PINCTRL */
2777 /* These "optional" allocation calls help prevent drivers from stomping
2778 * on each other, and help provide better diagnostics in debugfs.
2779 * They're called even less than the "set direction" calls.
2781 static int gpiod_request_commit(struct gpio_desc *desc, const char *label)
2783 struct gpio_chip *chip = desc->gdev->chip;
2785 unsigned long flags;
2789 label = kstrdup_const(label, GFP_KERNEL);
2794 spin_lock_irqsave(&gpio_lock, flags);
2796 /* NOTE: gpio_request() can be called in early boot,
2797 * before IRQs are enabled, for non-sleeping (SOC) GPIOs.
2800 if (test_and_set_bit(FLAG_REQUESTED, &desc->flags) == 0) {
2801 desc_set_label(desc, label ? : "?");
2809 if (chip->request) {
2810 /* chip->request may sleep */
2811 spin_unlock_irqrestore(&gpio_lock, flags);
2812 offset = gpio_chip_hwgpio(desc);
2813 if (gpiochip_line_is_valid(chip, offset))
2814 ret = chip->request(chip, offset);
2817 spin_lock_irqsave(&gpio_lock, flags);
2820 desc_set_label(desc, NULL);
2822 clear_bit(FLAG_REQUESTED, &desc->flags);
2826 if (chip->get_direction) {
2827 /* chip->get_direction may sleep */
2828 spin_unlock_irqrestore(&gpio_lock, flags);
2829 gpiod_get_direction(desc);
2830 spin_lock_irqsave(&gpio_lock, flags);
2833 spin_unlock_irqrestore(&gpio_lock, flags);
2838 * This descriptor validation needs to be inserted verbatim into each
2839 * function taking a descriptor, so we need to use a preprocessor
2840 * macro to avoid endless duplication. If the desc is NULL it is an
2841 * optional GPIO and calls should just bail out.
2843 static int validate_desc(const struct gpio_desc *desc, const char *func)
2848 pr_warn("%s: invalid GPIO (errorpointer)\n", func);
2849 return PTR_ERR(desc);
2852 pr_warn("%s: invalid GPIO (no device)\n", func);
2855 if (!desc->gdev->chip) {
2856 dev_warn(&desc->gdev->dev,
2857 "%s: backing chip is gone\n", func);
2863 #define VALIDATE_DESC(desc) do { \
2864 int __valid = validate_desc(desc, __func__); \
2869 #define VALIDATE_DESC_VOID(desc) do { \
2870 int __valid = validate_desc(desc, __func__); \
2875 int gpiod_request(struct gpio_desc *desc, const char *label)
2877 int ret = -EPROBE_DEFER;
2878 struct gpio_device *gdev;
2880 VALIDATE_DESC(desc);
2883 if (try_module_get(gdev->owner)) {
2884 ret = gpiod_request_commit(desc, label);
2886 module_put(gdev->owner);
2888 get_device(&gdev->dev);
2892 gpiod_dbg(desc, "%s: status %d\n", __func__, ret);
2897 static bool gpiod_free_commit(struct gpio_desc *desc)
2900 unsigned long flags;
2901 struct gpio_chip *chip;
2905 gpiod_unexport(desc);
2907 spin_lock_irqsave(&gpio_lock, flags);
2909 chip = desc->gdev->chip;
2910 if (chip && test_bit(FLAG_REQUESTED, &desc->flags)) {
2912 spin_unlock_irqrestore(&gpio_lock, flags);
2913 might_sleep_if(chip->can_sleep);
2914 chip->free(chip, gpio_chip_hwgpio(desc));
2915 spin_lock_irqsave(&gpio_lock, flags);
2917 kfree_const(desc->label);
2918 desc_set_label(desc, NULL);
2919 clear_bit(FLAG_ACTIVE_LOW, &desc->flags);
2920 clear_bit(FLAG_REQUESTED, &desc->flags);
2921 clear_bit(FLAG_OPEN_DRAIN, &desc->flags);
2922 clear_bit(FLAG_OPEN_SOURCE, &desc->flags);
2923 clear_bit(FLAG_PULL_UP, &desc->flags);
2924 clear_bit(FLAG_PULL_DOWN, &desc->flags);
2925 clear_bit(FLAG_BIAS_DISABLE, &desc->flags);
2926 clear_bit(FLAG_IS_HOGGED, &desc->flags);
2930 spin_unlock_irqrestore(&gpio_lock, flags);
2934 void gpiod_free(struct gpio_desc *desc)
2936 if (desc && desc->gdev && gpiod_free_commit(desc)) {
2937 module_put(desc->gdev->owner);
2938 put_device(&desc->gdev->dev);
2940 WARN_ON(extra_checks);
2945 * gpiochip_is_requested - return string iff signal was requested
2946 * @chip: controller managing the signal
2947 * @offset: of signal within controller's 0..(ngpio - 1) range
2949 * Returns NULL if the GPIO is not currently requested, else a string.
2950 * The string returned is the label passed to gpio_request(); if none has been
2951 * passed it is a meaningless, non-NULL constant.
2953 * This function is for use by GPIO controller drivers. The label can
2954 * help with diagnostics, and knowing that the signal is used as a GPIO
2955 * can help avoid accidentally multiplexing it to another controller.
2957 const char *gpiochip_is_requested(struct gpio_chip *chip, unsigned offset)
2959 struct gpio_desc *desc;
2961 if (offset >= chip->ngpio)
2964 desc = &chip->gpiodev->descs[offset];
2966 if (test_bit(FLAG_REQUESTED, &desc->flags) == 0)
2970 EXPORT_SYMBOL_GPL(gpiochip_is_requested);
2973 * gpiochip_request_own_desc - Allow GPIO chip to request its own descriptor
2975 * @hwnum: hardware number of the GPIO for which to request the descriptor
2976 * @label: label for the GPIO
2977 * @lflags: lookup flags for this GPIO or 0 if default, this can be used to
2978 * specify things like line inversion semantics with the machine flags
2979 * such as GPIO_OUT_LOW
2980 * @dflags: descriptor request flags for this GPIO or 0 if default, this
2981 * can be used to specify consumer semantics such as open drain
2983 * Function allows GPIO chip drivers to request and use their own GPIO
2984 * descriptors via gpiolib API. Difference to gpiod_request() is that this
2985 * function will not increase reference count of the GPIO chip module. This
2986 * allows the GPIO chip module to be unloaded as needed (we assume that the
2987 * GPIO chip driver handles freeing the GPIOs it has requested).
2990 * A pointer to the GPIO descriptor, or an ERR_PTR()-encoded negative error
2993 struct gpio_desc *gpiochip_request_own_desc(struct gpio_chip *chip,
2996 enum gpio_lookup_flags lflags,
2997 enum gpiod_flags dflags)
2999 struct gpio_desc *desc = gpiochip_get_desc(chip, hwnum);
3003 chip_err(chip, "failed to get GPIO descriptor\n");
3007 ret = gpiod_request_commit(desc, label);
3009 return ERR_PTR(ret);
3011 ret = gpiod_configure_flags(desc, label, lflags, dflags);
3013 chip_err(chip, "setup of own GPIO %s failed\n", label);
3014 gpiod_free_commit(desc);
3015 return ERR_PTR(ret);
3020 EXPORT_SYMBOL_GPL(gpiochip_request_own_desc);
3023 * gpiochip_free_own_desc - Free GPIO requested by the chip driver
3024 * @desc: GPIO descriptor to free
3026 * Function frees the given GPIO requested previously with
3027 * gpiochip_request_own_desc().
3029 void gpiochip_free_own_desc(struct gpio_desc *desc)
3032 gpiod_free_commit(desc);
3034 EXPORT_SYMBOL_GPL(gpiochip_free_own_desc);
3037 * Drivers MUST set GPIO direction before making get/set calls. In
3038 * some cases this is done in early boot, before IRQs are enabled.
3040 * As a rule these aren't called more than once (except for drivers
3041 * using the open-drain emulation idiom) so these are natural places
3042 * to accumulate extra debugging checks. Note that we can't (yet)
3043 * rely on gpio_request() having been called beforehand.
3046 static int gpio_do_set_config(struct gpio_chip *gc, unsigned int offset,
3047 unsigned long config)
3049 if (!gc->set_config)
3052 return gc->set_config(gc, offset, config);
3055 static int gpio_set_config(struct gpio_chip *gc, unsigned int offset,
3056 enum pin_config_param mode)
3058 unsigned long config;
3062 case PIN_CONFIG_BIAS_PULL_DOWN:
3063 case PIN_CONFIG_BIAS_PULL_UP:
3071 config = PIN_CONF_PACKED(mode, arg);
3072 return gpio_do_set_config(gc, offset, config);
3075 static int gpio_set_bias(struct gpio_chip *chip, struct gpio_desc *desc)
3080 if (test_bit(FLAG_BIAS_DISABLE, &desc->flags))
3081 bias = PIN_CONFIG_BIAS_DISABLE;
3082 else if (test_bit(FLAG_PULL_UP, &desc->flags))
3083 bias = PIN_CONFIG_BIAS_PULL_UP;
3084 else if (test_bit(FLAG_PULL_DOWN, &desc->flags))
3085 bias = PIN_CONFIG_BIAS_PULL_DOWN;
3088 ret = gpio_set_config(chip, gpio_chip_hwgpio(desc), bias);
3089 if (ret != -ENOTSUPP)
3096 * gpiod_direction_input - set the GPIO direction to input
3097 * @desc: GPIO to set to input
3099 * Set the direction of the passed GPIO to input, such as gpiod_get_value() can
3100 * be called safely on it.
3102 * Return 0 in case of success, else an error code.
3104 int gpiod_direction_input(struct gpio_desc *desc)
3106 struct gpio_chip *chip;
3109 VALIDATE_DESC(desc);
3110 chip = desc->gdev->chip;
3113 * It is legal to have no .get() and .direction_input() specified if
3114 * the chip is output-only, but you can't specify .direction_input()
3115 * and not support the .get() operation, that doesn't make sense.
3117 if (!chip->get && chip->direction_input) {
3119 "%s: missing get() but have direction_input()\n",
3125 * If we have a .direction_input() callback, things are simple,
3126 * just call it. Else we are some input-only chip so try to check the
3127 * direction (if .get_direction() is supported) else we silently
3128 * assume we are in input mode after this.
3130 if (chip->direction_input) {
3131 ret = chip->direction_input(chip, gpio_chip_hwgpio(desc));
3132 } else if (chip->get_direction &&
3133 (chip->get_direction(chip, gpio_chip_hwgpio(desc)) != 1)) {
3135 "%s: missing direction_input() operation and line is output\n",
3140 clear_bit(FLAG_IS_OUT, &desc->flags);
3141 ret = gpio_set_bias(chip, desc);
3144 trace_gpio_direction(desc_to_gpio(desc), 1, ret);
3148 EXPORT_SYMBOL_GPL(gpiod_direction_input);
3150 static int gpiod_direction_output_raw_commit(struct gpio_desc *desc, int value)
3152 struct gpio_chip *gc = desc->gdev->chip;
3157 * It's OK not to specify .direction_output() if the gpiochip is
3158 * output-only, but if there is then not even a .set() operation it
3159 * is pretty tricky to drive the output line.
3161 if (!gc->set && !gc->direction_output) {
3163 "%s: missing set() and direction_output() operations\n",
3168 if (gc->direction_output) {
3169 ret = gc->direction_output(gc, gpio_chip_hwgpio(desc), val);
3171 /* Check that we are in output mode if we can */
3172 if (gc->get_direction &&
3173 gc->get_direction(gc, gpio_chip_hwgpio(desc))) {
3175 "%s: missing direction_output() operation\n",
3180 * If we can't actively set the direction, we are some
3181 * output-only chip, so just drive the output as desired.
3183 gc->set(gc, gpio_chip_hwgpio(desc), val);
3187 set_bit(FLAG_IS_OUT, &desc->flags);
3188 trace_gpio_value(desc_to_gpio(desc), 0, val);
3189 trace_gpio_direction(desc_to_gpio(desc), 0, ret);
3194 * gpiod_direction_output_raw - set the GPIO direction to output
3195 * @desc: GPIO to set to output
3196 * @value: initial output value of the GPIO
3198 * Set the direction of the passed GPIO to output, such as gpiod_set_value() can
3199 * be called safely on it. The initial value of the output must be specified
3200 * as raw value on the physical line without regard for the ACTIVE_LOW status.
3202 * Return 0 in case of success, else an error code.
3204 int gpiod_direction_output_raw(struct gpio_desc *desc, int value)
3206 VALIDATE_DESC(desc);
3207 return gpiod_direction_output_raw_commit(desc, value);
3209 EXPORT_SYMBOL_GPL(gpiod_direction_output_raw);
3212 * gpiod_direction_output - set the GPIO direction to output
3213 * @desc: GPIO to set to output
3214 * @value: initial output value of the GPIO
3216 * Set the direction of the passed GPIO to output, such as gpiod_set_value() can
3217 * be called safely on it. The initial value of the output must be specified
3218 * as the logical value of the GPIO, i.e. taking its ACTIVE_LOW status into
3221 * Return 0 in case of success, else an error code.
3223 int gpiod_direction_output(struct gpio_desc *desc, int value)
3225 struct gpio_chip *gc;
3228 VALIDATE_DESC(desc);
3229 if (test_bit(FLAG_ACTIVE_LOW, &desc->flags))
3234 /* GPIOs used for enabled IRQs shall not be set as output */
3235 if (test_bit(FLAG_USED_AS_IRQ, &desc->flags) &&
3236 test_bit(FLAG_IRQ_IS_ENABLED, &desc->flags)) {
3238 "%s: tried to set a GPIO tied to an IRQ as output\n",
3243 gc = desc->gdev->chip;
3244 if (test_bit(FLAG_OPEN_DRAIN, &desc->flags)) {
3245 /* First see if we can enable open drain in hardware */
3246 ret = gpio_set_config(gc, gpio_chip_hwgpio(desc),
3247 PIN_CONFIG_DRIVE_OPEN_DRAIN);
3249 goto set_output_value;
3250 /* Emulate open drain by not actively driving the line high */
3252 ret = gpiod_direction_input(desc);
3253 goto set_output_flag;
3256 else if (test_bit(FLAG_OPEN_SOURCE, &desc->flags)) {
3257 ret = gpio_set_config(gc, gpio_chip_hwgpio(desc),
3258 PIN_CONFIG_DRIVE_OPEN_SOURCE);
3260 goto set_output_value;
3261 /* Emulate open source by not actively driving the line low */
3263 ret = gpiod_direction_input(desc);
3264 goto set_output_flag;
3267 gpio_set_config(gc, gpio_chip_hwgpio(desc),
3268 PIN_CONFIG_DRIVE_PUSH_PULL);
3272 ret = gpio_set_bias(gc, desc);
3275 return gpiod_direction_output_raw_commit(desc, value);
3279 * When emulating open-source or open-drain functionalities by not
3280 * actively driving the line (setting mode to input) we still need to
3281 * set the IS_OUT flag or otherwise we won't be able to set the line
3285 set_bit(FLAG_IS_OUT, &desc->flags);
3288 EXPORT_SYMBOL_GPL(gpiod_direction_output);
3291 * gpiod_set_debounce - sets @debounce time for a GPIO
3292 * @desc: descriptor of the GPIO for which to set debounce time
3293 * @debounce: debounce time in microseconds
3296 * 0 on success, %-ENOTSUPP if the controller doesn't support setting the
3299 int gpiod_set_debounce(struct gpio_desc *desc, unsigned debounce)
3301 struct gpio_chip *chip;
3302 unsigned long config;
3304 VALIDATE_DESC(desc);
3305 chip = desc->gdev->chip;
3307 config = pinconf_to_config_packed(PIN_CONFIG_INPUT_DEBOUNCE, debounce);
3308 return gpio_do_set_config(chip, gpio_chip_hwgpio(desc), config);
3310 EXPORT_SYMBOL_GPL(gpiod_set_debounce);
3313 * gpiod_set_transitory - Lose or retain GPIO state on suspend or reset
3314 * @desc: descriptor of the GPIO for which to configure persistence
3315 * @transitory: True to lose state on suspend or reset, false for persistence
3318 * 0 on success, otherwise a negative error code.
3320 int gpiod_set_transitory(struct gpio_desc *desc, bool transitory)
3322 struct gpio_chip *chip;
3323 unsigned long packed;
3327 VALIDATE_DESC(desc);
3329 * Handle FLAG_TRANSITORY first, enabling queries to gpiolib for
3330 * persistence state.
3332 assign_bit(FLAG_TRANSITORY, &desc->flags, transitory);
3334 /* If the driver supports it, set the persistence state now */
3335 chip = desc->gdev->chip;
3336 if (!chip->set_config)
3339 packed = pinconf_to_config_packed(PIN_CONFIG_PERSIST_STATE,
3341 gpio = gpio_chip_hwgpio(desc);
3342 rc = gpio_do_set_config(chip, gpio, packed);
3343 if (rc == -ENOTSUPP) {
3344 dev_dbg(&desc->gdev->dev, "Persistence not supported for GPIO %d\n",
3351 EXPORT_SYMBOL_GPL(gpiod_set_transitory);
3354 * gpiod_is_active_low - test whether a GPIO is active-low or not
3355 * @desc: the gpio descriptor to test
3357 * Returns 1 if the GPIO is active-low, 0 otherwise.
3359 int gpiod_is_active_low(const struct gpio_desc *desc)
3361 VALIDATE_DESC(desc);
3362 return test_bit(FLAG_ACTIVE_LOW, &desc->flags);
3364 EXPORT_SYMBOL_GPL(gpiod_is_active_low);
3367 * gpiod_toggle_active_low - toggle whether a GPIO is active-low or not
3368 * @desc: the gpio descriptor to change
3370 void gpiod_toggle_active_low(struct gpio_desc *desc)
3372 VALIDATE_DESC_VOID(desc);
3373 change_bit(FLAG_ACTIVE_LOW, &desc->flags);
3375 EXPORT_SYMBOL_GPL(gpiod_toggle_active_low);
3377 /* I/O calls are only valid after configuration completed; the relevant
3378 * "is this a valid GPIO" error checks should already have been done.
3380 * "Get" operations are often inlinable as reading a pin value register,
3381 * and masking the relevant bit in that register.
3383 * When "set" operations are inlinable, they involve writing that mask to
3384 * one register to set a low value, or a different register to set it high.
3385 * Otherwise locking is needed, so there may be little value to inlining.
3387 *------------------------------------------------------------------------
3389 * IMPORTANT!!! The hot paths -- get/set value -- assume that callers
3390 * have requested the GPIO. That can include implicit requesting by
3391 * a direction setting call. Marking a gpio as requested locks its chip
3392 * in memory, guaranteeing that these table lookups need no more locking
3393 * and that gpiochip_remove() will fail.
3395 * REVISIT when debugging, consider adding some instrumentation to ensure
3396 * that the GPIO was actually requested.
3399 static int gpiod_get_raw_value_commit(const struct gpio_desc *desc)
3401 struct gpio_chip *chip;
3405 chip = desc->gdev->chip;
3406 offset = gpio_chip_hwgpio(desc);
3407 value = chip->get ? chip->get(chip, offset) : -EIO;
3408 value = value < 0 ? value : !!value;
3409 trace_gpio_value(desc_to_gpio(desc), 1, value);
3413 static int gpio_chip_get_multiple(struct gpio_chip *chip,
3414 unsigned long *mask, unsigned long *bits)
3416 if (chip->get_multiple) {
3417 return chip->get_multiple(chip, mask, bits);
3418 } else if (chip->get) {
3421 for_each_set_bit(i, mask, chip->ngpio) {
3422 value = chip->get(chip, i);
3425 __assign_bit(i, bits, value);
3432 int gpiod_get_array_value_complex(bool raw, bool can_sleep,
3433 unsigned int array_size,
3434 struct gpio_desc **desc_array,
3435 struct gpio_array *array_info,
3436 unsigned long *value_bitmap)
3441 * Validate array_info against desc_array and its size.
3442 * It should immediately follow desc_array if both
3443 * have been obtained from the same gpiod_get_array() call.
3445 if (array_info && array_info->desc == desc_array &&
3446 array_size <= array_info->size &&
3447 (void *)array_info == desc_array + array_info->size) {
3449 WARN_ON(array_info->chip->can_sleep);
3451 ret = gpio_chip_get_multiple(array_info->chip,
3452 array_info->get_mask,
3457 if (!raw && !bitmap_empty(array_info->invert_mask, array_size))
3458 bitmap_xor(value_bitmap, value_bitmap,
3459 array_info->invert_mask, array_size);
3461 if (bitmap_full(array_info->get_mask, array_size))
3464 i = find_first_zero_bit(array_info->get_mask, array_size);
3469 while (i < array_size) {
3470 struct gpio_chip *chip = desc_array[i]->gdev->chip;
3471 unsigned long fastpath[2 * BITS_TO_LONGS(FASTPATH_NGPIO)];
3472 unsigned long *mask, *bits;
3475 if (likely(chip->ngpio <= FASTPATH_NGPIO)) {
3478 mask = kmalloc_array(2 * BITS_TO_LONGS(chip->ngpio),
3480 can_sleep ? GFP_KERNEL : GFP_ATOMIC);
3485 bits = mask + BITS_TO_LONGS(chip->ngpio);
3486 bitmap_zero(mask, chip->ngpio);
3489 WARN_ON(chip->can_sleep);
3491 /* collect all inputs belonging to the same chip */
3494 const struct gpio_desc *desc = desc_array[i];
3495 int hwgpio = gpio_chip_hwgpio(desc);
3497 __set_bit(hwgpio, mask);
3501 i = find_next_zero_bit(array_info->get_mask,
3503 } while ((i < array_size) &&
3504 (desc_array[i]->gdev->chip == chip));
3506 ret = gpio_chip_get_multiple(chip, mask, bits);
3508 if (mask != fastpath)
3513 for (j = first; j < i; ) {
3514 const struct gpio_desc *desc = desc_array[j];
3515 int hwgpio = gpio_chip_hwgpio(desc);
3516 int value = test_bit(hwgpio, bits);
3518 if (!raw && test_bit(FLAG_ACTIVE_LOW, &desc->flags))
3520 __assign_bit(j, value_bitmap, value);
3521 trace_gpio_value(desc_to_gpio(desc), 1, value);
3525 j = find_next_zero_bit(array_info->get_mask, i,
3529 if (mask != fastpath)
3536 * gpiod_get_raw_value() - return a gpio's raw value
3537 * @desc: gpio whose value will be returned
3539 * Return the GPIO's raw value, i.e. the value of the physical line disregarding
3540 * its ACTIVE_LOW status, or negative errno on failure.
3542 * This function can be called from contexts where we cannot sleep, and will
3543 * complain if the GPIO chip functions potentially sleep.
3545 int gpiod_get_raw_value(const struct gpio_desc *desc)
3547 VALIDATE_DESC(desc);
3548 /* Should be using gpiod_get_raw_value_cansleep() */
3549 WARN_ON(desc->gdev->chip->can_sleep);
3550 return gpiod_get_raw_value_commit(desc);
3552 EXPORT_SYMBOL_GPL(gpiod_get_raw_value);
3555 * gpiod_get_value() - return a gpio's value
3556 * @desc: gpio whose value will be returned
3558 * Return the GPIO's logical value, i.e. taking the ACTIVE_LOW status into
3559 * account, or negative errno on failure.
3561 * This function can be called from contexts where we cannot sleep, and will
3562 * complain if the GPIO chip functions potentially sleep.
3564 int gpiod_get_value(const struct gpio_desc *desc)
3568 VALIDATE_DESC(desc);
3569 /* Should be using gpiod_get_value_cansleep() */
3570 WARN_ON(desc->gdev->chip->can_sleep);
3572 value = gpiod_get_raw_value_commit(desc);
3576 if (test_bit(FLAG_ACTIVE_LOW, &desc->flags))
3581 EXPORT_SYMBOL_GPL(gpiod_get_value);
3584 * gpiod_get_raw_array_value() - read raw values from an array of GPIOs
3585 * @array_size: number of elements in the descriptor array / value bitmap
3586 * @desc_array: array of GPIO descriptors whose values will be read
3587 * @array_info: information on applicability of fast bitmap processing path
3588 * @value_bitmap: bitmap to store the read values
3590 * Read the raw values of the GPIOs, i.e. the values of the physical lines
3591 * without regard for their ACTIVE_LOW status. Return 0 in case of success,
3592 * else an error code.
3594 * This function can be called from contexts where we cannot sleep,
3595 * and it will complain if the GPIO chip functions potentially sleep.
3597 int gpiod_get_raw_array_value(unsigned int array_size,
3598 struct gpio_desc **desc_array,
3599 struct gpio_array *array_info,
3600 unsigned long *value_bitmap)
3604 return gpiod_get_array_value_complex(true, false, array_size,
3605 desc_array, array_info,
3608 EXPORT_SYMBOL_GPL(gpiod_get_raw_array_value);
3611 * gpiod_get_array_value() - read values from an array of GPIOs
3612 * @array_size: number of elements in the descriptor array / value bitmap
3613 * @desc_array: array of GPIO descriptors whose values will be read
3614 * @array_info: information on applicability of fast bitmap processing path
3615 * @value_bitmap: bitmap to store the read values
3617 * Read the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status
3618 * into account. Return 0 in case of success, else an error code.
3620 * This function can be called from contexts where we cannot sleep,
3621 * and it will complain if the GPIO chip functions potentially sleep.
3623 int gpiod_get_array_value(unsigned int array_size,
3624 struct gpio_desc **desc_array,
3625 struct gpio_array *array_info,
3626 unsigned long *value_bitmap)
3630 return gpiod_get_array_value_complex(false, false, array_size,
3631 desc_array, array_info,
3634 EXPORT_SYMBOL_GPL(gpiod_get_array_value);
3637 * gpio_set_open_drain_value_commit() - Set the open drain gpio's value.
3638 * @desc: gpio descriptor whose state need to be set.
3639 * @value: Non-zero for setting it HIGH otherwise it will set to LOW.
3641 static void gpio_set_open_drain_value_commit(struct gpio_desc *desc, bool value)
3644 struct gpio_chip *chip = desc->gdev->chip;
3645 int offset = gpio_chip_hwgpio(desc);
3648 ret = chip->direction_input(chip, offset);
3650 ret = chip->direction_output(chip, offset, 0);
3652 set_bit(FLAG_IS_OUT, &desc->flags);
3654 trace_gpio_direction(desc_to_gpio(desc), value, ret);
3657 "%s: Error in set_value for open drain err %d\n",
3662 * _gpio_set_open_source_value() - Set the open source gpio's value.
3663 * @desc: gpio descriptor whose state need to be set.
3664 * @value: Non-zero for setting it HIGH otherwise it will set to LOW.
3666 static void gpio_set_open_source_value_commit(struct gpio_desc *desc, bool value)
3669 struct gpio_chip *chip = desc->gdev->chip;
3670 int offset = gpio_chip_hwgpio(desc);
3673 ret = chip->direction_output(chip, offset, 1);
3675 set_bit(FLAG_IS_OUT, &desc->flags);
3677 ret = chip->direction_input(chip, offset);
3679 trace_gpio_direction(desc_to_gpio(desc), !value, ret);
3682 "%s: Error in set_value for open source err %d\n",
3686 static void gpiod_set_raw_value_commit(struct gpio_desc *desc, bool value)
3688 struct gpio_chip *chip;
3690 chip = desc->gdev->chip;
3691 trace_gpio_value(desc_to_gpio(desc), 0, value);
3692 chip->set(chip, gpio_chip_hwgpio(desc), value);
3696 * set multiple outputs on the same chip;
3697 * use the chip's set_multiple function if available;
3698 * otherwise set the outputs sequentially;
3699 * @mask: bit mask array; one bit per output; BITS_PER_LONG bits per word
3700 * defines which outputs are to be changed
3701 * @bits: bit value array; one bit per output; BITS_PER_LONG bits per word
3702 * defines the values the outputs specified by mask are to be set to
3704 static void gpio_chip_set_multiple(struct gpio_chip *chip,
3705 unsigned long *mask, unsigned long *bits)
3707 if (chip->set_multiple) {
3708 chip->set_multiple(chip, mask, bits);
3712 /* set outputs if the corresponding mask bit is set */
3713 for_each_set_bit(i, mask, chip->ngpio)
3714 chip->set(chip, i, test_bit(i, bits));
3718 int gpiod_set_array_value_complex(bool raw, bool can_sleep,
3719 unsigned int array_size,
3720 struct gpio_desc **desc_array,
3721 struct gpio_array *array_info,
3722 unsigned long *value_bitmap)
3727 * Validate array_info against desc_array and its size.
3728 * It should immediately follow desc_array if both
3729 * have been obtained from the same gpiod_get_array() call.
3731 if (array_info && array_info->desc == desc_array &&
3732 array_size <= array_info->size &&
3733 (void *)array_info == desc_array + array_info->size) {
3735 WARN_ON(array_info->chip->can_sleep);
3737 if (!raw && !bitmap_empty(array_info->invert_mask, array_size))
3738 bitmap_xor(value_bitmap, value_bitmap,
3739 array_info->invert_mask, array_size);
3741 gpio_chip_set_multiple(array_info->chip, array_info->set_mask,
3744 if (bitmap_full(array_info->set_mask, array_size))
3747 i = find_first_zero_bit(array_info->set_mask, array_size);
3752 while (i < array_size) {
3753 struct gpio_chip *chip = desc_array[i]->gdev->chip;
3754 unsigned long fastpath[2 * BITS_TO_LONGS(FASTPATH_NGPIO)];
3755 unsigned long *mask, *bits;
3758 if (likely(chip->ngpio <= FASTPATH_NGPIO)) {
3761 mask = kmalloc_array(2 * BITS_TO_LONGS(chip->ngpio),
3763 can_sleep ? GFP_KERNEL : GFP_ATOMIC);
3768 bits = mask + BITS_TO_LONGS(chip->ngpio);
3769 bitmap_zero(mask, chip->ngpio);
3772 WARN_ON(chip->can_sleep);
3775 struct gpio_desc *desc = desc_array[i];
3776 int hwgpio = gpio_chip_hwgpio(desc);
3777 int value = test_bit(i, value_bitmap);
3780 * Pins applicable for fast input but not for
3781 * fast output processing may have been already
3782 * inverted inside the fast path, skip them.
3784 if (!raw && !(array_info &&
3785 test_bit(i, array_info->invert_mask)) &&
3786 test_bit(FLAG_ACTIVE_LOW, &desc->flags))
3788 trace_gpio_value(desc_to_gpio(desc), 0, value);
3790 * collect all normal outputs belonging to the same chip
3791 * open drain and open source outputs are set individually
3793 if (test_bit(FLAG_OPEN_DRAIN, &desc->flags) && !raw) {
3794 gpio_set_open_drain_value_commit(desc, value);
3795 } else if (test_bit(FLAG_OPEN_SOURCE, &desc->flags) && !raw) {
3796 gpio_set_open_source_value_commit(desc, value);
3798 __set_bit(hwgpio, mask);
3799 __assign_bit(hwgpio, bits, value);
3805 i = find_next_zero_bit(array_info->set_mask,
3807 } while ((i < array_size) &&
3808 (desc_array[i]->gdev->chip == chip));
3809 /* push collected bits to outputs */
3811 gpio_chip_set_multiple(chip, mask, bits);
3813 if (mask != fastpath)
3820 * gpiod_set_raw_value() - assign a gpio's raw value
3821 * @desc: gpio whose value will be assigned
3822 * @value: value to assign
3824 * Set the raw value of the GPIO, i.e. the value of its physical line without
3825 * regard for its ACTIVE_LOW status.
3827 * This function can be called from contexts where we cannot sleep, and will
3828 * complain if the GPIO chip functions potentially sleep.
3830 void gpiod_set_raw_value(struct gpio_desc *desc, int value)
3832 VALIDATE_DESC_VOID(desc);
3833 /* Should be using gpiod_set_raw_value_cansleep() */
3834 WARN_ON(desc->gdev->chip->can_sleep);
3835 gpiod_set_raw_value_commit(desc, value);
3837 EXPORT_SYMBOL_GPL(gpiod_set_raw_value);
3840 * gpiod_set_value_nocheck() - set a GPIO line value without checking
3841 * @desc: the descriptor to set the value on
3842 * @value: value to set
3844 * This sets the value of a GPIO line backing a descriptor, applying
3845 * different semantic quirks like active low and open drain/source
3848 static void gpiod_set_value_nocheck(struct gpio_desc *desc, int value)
3850 if (test_bit(FLAG_ACTIVE_LOW, &desc->flags))
3852 if (test_bit(FLAG_OPEN_DRAIN, &desc->flags))
3853 gpio_set_open_drain_value_commit(desc, value);
3854 else if (test_bit(FLAG_OPEN_SOURCE, &desc->flags))
3855 gpio_set_open_source_value_commit(desc, value);
3857 gpiod_set_raw_value_commit(desc, value);
3861 * gpiod_set_value() - assign a gpio's value
3862 * @desc: gpio whose value will be assigned
3863 * @value: value to assign
3865 * Set the logical value of the GPIO, i.e. taking its ACTIVE_LOW,
3866 * OPEN_DRAIN and OPEN_SOURCE flags into account.
3868 * This function can be called from contexts where we cannot sleep, and will
3869 * complain if the GPIO chip functions potentially sleep.
3871 void gpiod_set_value(struct gpio_desc *desc, int value)
3873 VALIDATE_DESC_VOID(desc);
3874 /* Should be using gpiod_set_value_cansleep() */
3875 WARN_ON(desc->gdev->chip->can_sleep);
3876 gpiod_set_value_nocheck(desc, value);
3878 EXPORT_SYMBOL_GPL(gpiod_set_value);
3881 * gpiod_set_raw_array_value() - assign values to an array of GPIOs
3882 * @array_size: number of elements in the descriptor array / value bitmap
3883 * @desc_array: array of GPIO descriptors whose values will be assigned
3884 * @array_info: information on applicability of fast bitmap processing path
3885 * @value_bitmap: bitmap of values to assign
3887 * Set the raw values of the GPIOs, i.e. the values of the physical lines
3888 * without regard for their ACTIVE_LOW status.
3890 * This function can be called from contexts where we cannot sleep, and will
3891 * complain if the GPIO chip functions potentially sleep.
3893 int gpiod_set_raw_array_value(unsigned int array_size,
3894 struct gpio_desc **desc_array,
3895 struct gpio_array *array_info,
3896 unsigned long *value_bitmap)
3900 return gpiod_set_array_value_complex(true, false, array_size,
3901 desc_array, array_info, value_bitmap);
3903 EXPORT_SYMBOL_GPL(gpiod_set_raw_array_value);
3906 * gpiod_set_array_value() - assign values to an array of GPIOs
3907 * @array_size: number of elements in the descriptor array / value bitmap
3908 * @desc_array: array of GPIO descriptors whose values will be assigned
3909 * @array_info: information on applicability of fast bitmap processing path
3910 * @value_bitmap: bitmap of values to assign
3912 * Set the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status
3915 * This function can be called from contexts where we cannot sleep, and will
3916 * complain if the GPIO chip functions potentially sleep.
3918 int gpiod_set_array_value(unsigned int array_size,
3919 struct gpio_desc **desc_array,
3920 struct gpio_array *array_info,
3921 unsigned long *value_bitmap)
3925 return gpiod_set_array_value_complex(false, false, array_size,
3926 desc_array, array_info,
3929 EXPORT_SYMBOL_GPL(gpiod_set_array_value);
3932 * gpiod_cansleep() - report whether gpio value access may sleep
3933 * @desc: gpio to check
3936 int gpiod_cansleep(const struct gpio_desc *desc)
3938 VALIDATE_DESC(desc);
3939 return desc->gdev->chip->can_sleep;
3941 EXPORT_SYMBOL_GPL(gpiod_cansleep);
3944 * gpiod_set_consumer_name() - set the consumer name for the descriptor
3945 * @desc: gpio to set the consumer name on
3946 * @name: the new consumer name
3948 int gpiod_set_consumer_name(struct gpio_desc *desc, const char *name)
3950 VALIDATE_DESC(desc);
3952 name = kstrdup_const(name, GFP_KERNEL);
3957 kfree_const(desc->label);
3958 desc_set_label(desc, name);
3962 EXPORT_SYMBOL_GPL(gpiod_set_consumer_name);
3965 * gpiod_to_irq() - return the IRQ corresponding to a GPIO
3966 * @desc: gpio whose IRQ will be returned (already requested)
3968 * Return the IRQ corresponding to the passed GPIO, or an error code in case of
3971 int gpiod_to_irq(const struct gpio_desc *desc)
3973 struct gpio_chip *chip;
3977 * Cannot VALIDATE_DESC() here as gpiod_to_irq() consumer semantics
3978 * requires this function to not return zero on an invalid descriptor
3979 * but rather a negative error number.
3981 if (!desc || IS_ERR(desc) || !desc->gdev || !desc->gdev->chip)
3984 chip = desc->gdev->chip;
3985 offset = gpio_chip_hwgpio(desc);
3987 int retirq = chip->to_irq(chip, offset);
3989 /* Zero means NO_IRQ */
3997 EXPORT_SYMBOL_GPL(gpiod_to_irq);
4000 * gpiochip_lock_as_irq() - lock a GPIO to be used as IRQ
4001 * @chip: the chip the GPIO to lock belongs to
4002 * @offset: the offset of the GPIO to lock as IRQ
4004 * This is used directly by GPIO drivers that want to lock down
4005 * a certain GPIO line to be used for IRQs.
4007 int gpiochip_lock_as_irq(struct gpio_chip *chip, unsigned int offset)
4009 struct gpio_desc *desc;
4011 desc = gpiochip_get_desc(chip, offset);
4013 return PTR_ERR(desc);
4016 * If it's fast: flush the direction setting if something changed
4019 if (!chip->can_sleep && chip->get_direction) {
4020 int dir = gpiod_get_direction(desc);
4023 chip_err(chip, "%s: cannot get GPIO direction\n",
4029 if (test_bit(FLAG_IS_OUT, &desc->flags)) {
4031 "%s: tried to flag a GPIO set as output for IRQ\n",
4036 set_bit(FLAG_USED_AS_IRQ, &desc->flags);
4037 set_bit(FLAG_IRQ_IS_ENABLED, &desc->flags);
4040 * If the consumer has not set up a label (such as when the
4041 * IRQ is referenced from .to_irq()) we set up a label here
4042 * so it is clear this is used as an interrupt.
4045 desc_set_label(desc, "interrupt");
4049 EXPORT_SYMBOL_GPL(gpiochip_lock_as_irq);
4052 * gpiochip_unlock_as_irq() - unlock a GPIO used as IRQ
4053 * @chip: the chip the GPIO to lock belongs to
4054 * @offset: the offset of the GPIO to lock as IRQ
4056 * This is used directly by GPIO drivers that want to indicate
4057 * that a certain GPIO is no longer used exclusively for IRQ.
4059 void gpiochip_unlock_as_irq(struct gpio_chip *chip, unsigned int offset)
4061 struct gpio_desc *desc;
4063 desc = gpiochip_get_desc(chip, offset);
4067 clear_bit(FLAG_USED_AS_IRQ, &desc->flags);
4068 clear_bit(FLAG_IRQ_IS_ENABLED, &desc->flags);
4070 /* If we only had this marking, erase it */
4071 if (desc->label && !strcmp(desc->label, "interrupt"))
4072 desc_set_label(desc, NULL);
4074 EXPORT_SYMBOL_GPL(gpiochip_unlock_as_irq);
4076 void gpiochip_disable_irq(struct gpio_chip *chip, unsigned int offset)
4078 struct gpio_desc *desc = gpiochip_get_desc(chip, offset);
4080 if (!IS_ERR(desc) &&
4081 !WARN_ON(!test_bit(FLAG_USED_AS_IRQ, &desc->flags)))
4082 clear_bit(FLAG_IRQ_IS_ENABLED, &desc->flags);
4084 EXPORT_SYMBOL_GPL(gpiochip_disable_irq);
4086 void gpiochip_enable_irq(struct gpio_chip *chip, unsigned int offset)
4088 struct gpio_desc *desc = gpiochip_get_desc(chip, offset);
4090 if (!IS_ERR(desc) &&
4091 !WARN_ON(!test_bit(FLAG_USED_AS_IRQ, &desc->flags))) {
4092 WARN_ON(test_bit(FLAG_IS_OUT, &desc->flags));
4093 set_bit(FLAG_IRQ_IS_ENABLED, &desc->flags);
4096 EXPORT_SYMBOL_GPL(gpiochip_enable_irq);
4098 bool gpiochip_line_is_irq(struct gpio_chip *chip, unsigned int offset)
4100 if (offset >= chip->ngpio)
4103 return test_bit(FLAG_USED_AS_IRQ, &chip->gpiodev->descs[offset].flags);
4105 EXPORT_SYMBOL_GPL(gpiochip_line_is_irq);
4107 int gpiochip_reqres_irq(struct gpio_chip *chip, unsigned int offset)
4111 if (!try_module_get(chip->gpiodev->owner))
4114 ret = gpiochip_lock_as_irq(chip, offset);
4116 chip_err(chip, "unable to lock HW IRQ %u for IRQ\n", offset);
4117 module_put(chip->gpiodev->owner);
4122 EXPORT_SYMBOL_GPL(gpiochip_reqres_irq);
4124 void gpiochip_relres_irq(struct gpio_chip *chip, unsigned int offset)
4126 gpiochip_unlock_as_irq(chip, offset);
4127 module_put(chip->gpiodev->owner);
4129 EXPORT_SYMBOL_GPL(gpiochip_relres_irq);
4131 bool gpiochip_line_is_open_drain(struct gpio_chip *chip, unsigned int offset)
4133 if (offset >= chip->ngpio)
4136 return test_bit(FLAG_OPEN_DRAIN, &chip->gpiodev->descs[offset].flags);
4138 EXPORT_SYMBOL_GPL(gpiochip_line_is_open_drain);
4140 bool gpiochip_line_is_open_source(struct gpio_chip *chip, unsigned int offset)
4142 if (offset >= chip->ngpio)
4145 return test_bit(FLAG_OPEN_SOURCE, &chip->gpiodev->descs[offset].flags);
4147 EXPORT_SYMBOL_GPL(gpiochip_line_is_open_source);
4149 bool gpiochip_line_is_persistent(struct gpio_chip *chip, unsigned int offset)
4151 if (offset >= chip->ngpio)
4154 return !test_bit(FLAG_TRANSITORY, &chip->gpiodev->descs[offset].flags);
4156 EXPORT_SYMBOL_GPL(gpiochip_line_is_persistent);
4159 * gpiod_get_raw_value_cansleep() - return a gpio's raw value
4160 * @desc: gpio whose value will be returned
4162 * Return the GPIO's raw value, i.e. the value of the physical line disregarding
4163 * its ACTIVE_LOW status, or negative errno on failure.
4165 * This function is to be called from contexts that can sleep.
4167 int gpiod_get_raw_value_cansleep(const struct gpio_desc *desc)
4169 might_sleep_if(extra_checks);
4170 VALIDATE_DESC(desc);
4171 return gpiod_get_raw_value_commit(desc);
4173 EXPORT_SYMBOL_GPL(gpiod_get_raw_value_cansleep);
4176 * gpiod_get_value_cansleep() - return a gpio's value
4177 * @desc: gpio whose value will be returned
4179 * Return the GPIO's logical value, i.e. taking the ACTIVE_LOW status into
4180 * account, or negative errno on failure.
4182 * This function is to be called from contexts that can sleep.
4184 int gpiod_get_value_cansleep(const struct gpio_desc *desc)
4188 might_sleep_if(extra_checks);
4189 VALIDATE_DESC(desc);
4190 value = gpiod_get_raw_value_commit(desc);
4194 if (test_bit(FLAG_ACTIVE_LOW, &desc->flags))
4199 EXPORT_SYMBOL_GPL(gpiod_get_value_cansleep);
4202 * gpiod_get_raw_array_value_cansleep() - read raw values from an array of GPIOs
4203 * @array_size: number of elements in the descriptor array / value bitmap
4204 * @desc_array: array of GPIO descriptors whose values will be read
4205 * @array_info: information on applicability of fast bitmap processing path
4206 * @value_bitmap: bitmap to store the read values
4208 * Read the raw values of the GPIOs, i.e. the values of the physical lines
4209 * without regard for their ACTIVE_LOW status. Return 0 in case of success,
4210 * else an error code.
4212 * This function is to be called from contexts that can sleep.
4214 int gpiod_get_raw_array_value_cansleep(unsigned int array_size,
4215 struct gpio_desc **desc_array,
4216 struct gpio_array *array_info,
4217 unsigned long *value_bitmap)
4219 might_sleep_if(extra_checks);
4222 return gpiod_get_array_value_complex(true, true, array_size,
4223 desc_array, array_info,
4226 EXPORT_SYMBOL_GPL(gpiod_get_raw_array_value_cansleep);
4229 * gpiod_get_array_value_cansleep() - read values from an array of GPIOs
4230 * @array_size: number of elements in the descriptor array / value bitmap
4231 * @desc_array: array of GPIO descriptors whose values will be read
4232 * @array_info: information on applicability of fast bitmap processing path
4233 * @value_bitmap: bitmap to store the read values
4235 * Read the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status
4236 * into account. Return 0 in case of success, else an error code.
4238 * This function is to be called from contexts that can sleep.
4240 int gpiod_get_array_value_cansleep(unsigned int array_size,
4241 struct gpio_desc **desc_array,
4242 struct gpio_array *array_info,
4243 unsigned long *value_bitmap)
4245 might_sleep_if(extra_checks);
4248 return gpiod_get_array_value_complex(false, true, array_size,
4249 desc_array, array_info,
4252 EXPORT_SYMBOL_GPL(gpiod_get_array_value_cansleep);
4255 * gpiod_set_raw_value_cansleep() - assign a gpio's raw value
4256 * @desc: gpio whose value will be assigned
4257 * @value: value to assign
4259 * Set the raw value of the GPIO, i.e. the value of its physical line without
4260 * regard for its ACTIVE_LOW status.
4262 * This function is to be called from contexts that can sleep.
4264 void gpiod_set_raw_value_cansleep(struct gpio_desc *desc, int value)
4266 might_sleep_if(extra_checks);
4267 VALIDATE_DESC_VOID(desc);
4268 gpiod_set_raw_value_commit(desc, value);
4270 EXPORT_SYMBOL_GPL(gpiod_set_raw_value_cansleep);
4273 * gpiod_set_value_cansleep() - assign a gpio's value
4274 * @desc: gpio whose value will be assigned
4275 * @value: value to assign
4277 * Set the logical value of the GPIO, i.e. taking its ACTIVE_LOW status into
4280 * This function is to be called from contexts that can sleep.
4282 void gpiod_set_value_cansleep(struct gpio_desc *desc, int value)
4284 might_sleep_if(extra_checks);
4285 VALIDATE_DESC_VOID(desc);
4286 gpiod_set_value_nocheck(desc, value);
4288 EXPORT_SYMBOL_GPL(gpiod_set_value_cansleep);
4291 * gpiod_set_raw_array_value_cansleep() - assign values to an array of GPIOs
4292 * @array_size: number of elements in the descriptor array / value bitmap
4293 * @desc_array: array of GPIO descriptors whose values will be assigned
4294 * @array_info: information on applicability of fast bitmap processing path
4295 * @value_bitmap: bitmap of values to assign
4297 * Set the raw values of the GPIOs, i.e. the values of the physical lines
4298 * without regard for their ACTIVE_LOW status.
4300 * This function is to be called from contexts that can sleep.
4302 int gpiod_set_raw_array_value_cansleep(unsigned int array_size,
4303 struct gpio_desc **desc_array,
4304 struct gpio_array *array_info,
4305 unsigned long *value_bitmap)
4307 might_sleep_if(extra_checks);
4310 return gpiod_set_array_value_complex(true, true, array_size, desc_array,
4311 array_info, value_bitmap);
4313 EXPORT_SYMBOL_GPL(gpiod_set_raw_array_value_cansleep);
4316 * gpiod_add_lookup_tables() - register GPIO device consumers
4317 * @tables: list of tables of consumers to register
4318 * @n: number of tables in the list
4320 void gpiod_add_lookup_tables(struct gpiod_lookup_table **tables, size_t n)
4324 mutex_lock(&gpio_lookup_lock);
4326 for (i = 0; i < n; i++)
4327 list_add_tail(&tables[i]->list, &gpio_lookup_list);
4329 mutex_unlock(&gpio_lookup_lock);
4333 * gpiod_set_array_value_cansleep() - assign values to an array of GPIOs
4334 * @array_size: number of elements in the descriptor array / value bitmap
4335 * @desc_array: array of GPIO descriptors whose values will be assigned
4336 * @array_info: information on applicability of fast bitmap processing path
4337 * @value_bitmap: bitmap of values to assign
4339 * Set the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status
4342 * This function is to be called from contexts that can sleep.
4344 int gpiod_set_array_value_cansleep(unsigned int array_size,
4345 struct gpio_desc **desc_array,
4346 struct gpio_array *array_info,
4347 unsigned long *value_bitmap)
4349 might_sleep_if(extra_checks);
4352 return gpiod_set_array_value_complex(false, true, array_size,
4353 desc_array, array_info,
4356 EXPORT_SYMBOL_GPL(gpiod_set_array_value_cansleep);
4359 * gpiod_add_lookup_table() - register GPIO device consumers
4360 * @table: table of consumers to register
4362 void gpiod_add_lookup_table(struct gpiod_lookup_table *table)
4364 mutex_lock(&gpio_lookup_lock);
4366 list_add_tail(&table->list, &gpio_lookup_list);
4368 mutex_unlock(&gpio_lookup_lock);
4370 EXPORT_SYMBOL_GPL(gpiod_add_lookup_table);
4373 * gpiod_remove_lookup_table() - unregister GPIO device consumers
4374 * @table: table of consumers to unregister
4376 void gpiod_remove_lookup_table(struct gpiod_lookup_table *table)
4378 mutex_lock(&gpio_lookup_lock);
4380 list_del(&table->list);
4382 mutex_unlock(&gpio_lookup_lock);
4384 EXPORT_SYMBOL_GPL(gpiod_remove_lookup_table);
4387 * gpiod_add_hogs() - register a set of GPIO hogs from machine code
4388 * @hogs: table of gpio hog entries with a zeroed sentinel at the end
4390 void gpiod_add_hogs(struct gpiod_hog *hogs)
4392 struct gpio_chip *chip;
4393 struct gpiod_hog *hog;
4395 mutex_lock(&gpio_machine_hogs_mutex);
4397 for (hog = &hogs[0]; hog->chip_label; hog++) {
4398 list_add_tail(&hog->list, &gpio_machine_hogs);
4401 * The chip may have been registered earlier, so check if it
4402 * exists and, if so, try to hog the line now.
4404 chip = find_chip_by_name(hog->chip_label);
4406 gpiochip_machine_hog(chip, hog);
4409 mutex_unlock(&gpio_machine_hogs_mutex);
4411 EXPORT_SYMBOL_GPL(gpiod_add_hogs);
4413 static struct gpiod_lookup_table *gpiod_find_lookup_table(struct device *dev)
4415 const char *dev_id = dev ? dev_name(dev) : NULL;
4416 struct gpiod_lookup_table *table;
4418 mutex_lock(&gpio_lookup_lock);
4420 list_for_each_entry(table, &gpio_lookup_list, list) {
4421 if (table->dev_id && dev_id) {
4423 * Valid strings on both ends, must be identical to have
4426 if (!strcmp(table->dev_id, dev_id))
4430 * One of the pointers is NULL, so both must be to have
4433 if (dev_id == table->dev_id)
4440 mutex_unlock(&gpio_lookup_lock);
4444 static struct gpio_desc *gpiod_find(struct device *dev, const char *con_id,
4445 unsigned int idx, unsigned long *flags)
4447 struct gpio_desc *desc = ERR_PTR(-ENOENT);
4448 struct gpiod_lookup_table *table;
4449 struct gpiod_lookup *p;
4451 table = gpiod_find_lookup_table(dev);
4455 for (p = &table->table[0]; p->chip_label; p++) {
4456 struct gpio_chip *chip;
4458 /* idx must always match exactly */
4462 /* If the lookup entry has a con_id, require exact match */
4463 if (p->con_id && (!con_id || strcmp(p->con_id, con_id)))
4466 chip = find_chip_by_name(p->chip_label);
4470 * As the lookup table indicates a chip with
4471 * p->chip_label should exist, assume it may
4472 * still appear later and let the interested
4473 * consumer be probed again or let the Deferred
4474 * Probe infrastructure handle the error.
4476 dev_warn(dev, "cannot find GPIO chip %s, deferring\n",
4478 return ERR_PTR(-EPROBE_DEFER);
4481 if (chip->ngpio <= p->chip_hwnum) {
4483 "requested GPIO %u (%u) is out of range [0..%u] for chip %s\n",
4484 idx, p->chip_hwnum, chip->ngpio - 1,
4486 return ERR_PTR(-EINVAL);
4489 desc = gpiochip_get_desc(chip, p->chip_hwnum);
4498 static int platform_gpio_count(struct device *dev, const char *con_id)
4500 struct gpiod_lookup_table *table;
4501 struct gpiod_lookup *p;
4502 unsigned int count = 0;
4504 table = gpiod_find_lookup_table(dev);
4508 for (p = &table->table[0]; p->chip_label; p++) {
4509 if ((con_id && p->con_id && !strcmp(con_id, p->con_id)) ||
4510 (!con_id && !p->con_id))
4520 * fwnode_gpiod_get_index - obtain a GPIO from firmware node
4521 * @fwnode: handle of the firmware node
4522 * @con_id: function within the GPIO consumer
4523 * @index: index of the GPIO to obtain for the consumer
4524 * @flags: GPIO initialization flags
4525 * @label: label to attach to the requested GPIO
4527 * This function can be used for drivers that get their configuration
4528 * from opaque firmware.
4530 * The function properly finds the corresponding GPIO using whatever is the
4531 * underlying firmware interface and then makes sure that the GPIO
4532 * descriptor is requested before it is returned to the caller.
4535 * On successful request the GPIO pin is configured in accordance with
4538 * In case of error an ERR_PTR() is returned.
4540 struct gpio_desc *fwnode_gpiod_get_index(struct fwnode_handle *fwnode,
4541 const char *con_id, int index,
4542 enum gpiod_flags flags,
4545 struct gpio_desc *desc;
4546 char prop_name[32]; /* 32 is max size of property name */
4549 for (i = 0; i < ARRAY_SIZE(gpio_suffixes); i++) {
4551 snprintf(prop_name, sizeof(prop_name), "%s-%s",
4552 con_id, gpio_suffixes[i]);
4554 snprintf(prop_name, sizeof(prop_name), "%s",
4557 desc = fwnode_get_named_gpiod(fwnode, prop_name, index, flags,
4559 if (!IS_ERR(desc) || (PTR_ERR(desc) != -ENOENT))
4565 EXPORT_SYMBOL_GPL(fwnode_gpiod_get_index);
4568 * gpiod_count - return the number of GPIOs associated with a device / function
4569 * or -ENOENT if no GPIO has been assigned to the requested function
4570 * @dev: GPIO consumer, can be NULL for system-global GPIOs
4571 * @con_id: function within the GPIO consumer
4573 int gpiod_count(struct device *dev, const char *con_id)
4575 int count = -ENOENT;
4577 if (IS_ENABLED(CONFIG_OF) && dev && dev->of_node)
4578 count = of_gpio_get_count(dev, con_id);
4579 else if (IS_ENABLED(CONFIG_ACPI) && dev && ACPI_HANDLE(dev))
4580 count = acpi_gpio_count(dev, con_id);
4583 count = platform_gpio_count(dev, con_id);
4587 EXPORT_SYMBOL_GPL(gpiod_count);
4590 * gpiod_get - obtain a GPIO for a given GPIO function
4591 * @dev: GPIO consumer, can be NULL for system-global GPIOs
4592 * @con_id: function within the GPIO consumer
4593 * @flags: optional GPIO initialization flags
4595 * Return the GPIO descriptor corresponding to the function con_id of device
4596 * dev, -ENOENT if no GPIO has been assigned to the requested function, or
4597 * another IS_ERR() code if an error occurred while trying to acquire the GPIO.
4599 struct gpio_desc *__must_check gpiod_get(struct device *dev, const char *con_id,
4600 enum gpiod_flags flags)
4602 return gpiod_get_index(dev, con_id, 0, flags);
4604 EXPORT_SYMBOL_GPL(gpiod_get);
4607 * gpiod_get_optional - obtain an optional GPIO for a given GPIO function
4608 * @dev: GPIO consumer, can be NULL for system-global GPIOs
4609 * @con_id: function within the GPIO consumer
4610 * @flags: optional GPIO initialization flags
4612 * This is equivalent to gpiod_get(), except that when no GPIO was assigned to
4613 * the requested function it will return NULL. This is convenient for drivers
4614 * that need to handle optional GPIOs.
4616 struct gpio_desc *__must_check gpiod_get_optional(struct device *dev,
4618 enum gpiod_flags flags)
4620 return gpiod_get_index_optional(dev, con_id, 0, flags);
4622 EXPORT_SYMBOL_GPL(gpiod_get_optional);
4626 * gpiod_configure_flags - helper function to configure a given GPIO
4627 * @desc: gpio whose value will be assigned
4628 * @con_id: function within the GPIO consumer
4629 * @lflags: bitmask of gpio_lookup_flags GPIO_* values - returned from
4630 * of_find_gpio() or of_get_gpio_hog()
4631 * @dflags: gpiod_flags - optional GPIO initialization flags
4633 * Return 0 on success, -ENOENT if no GPIO has been assigned to the
4634 * requested function and/or index, or another IS_ERR() code if an error
4635 * occurred while trying to acquire the GPIO.
4637 int gpiod_configure_flags(struct gpio_desc *desc, const char *con_id,
4638 unsigned long lflags, enum gpiod_flags dflags)
4642 if (lflags & GPIO_ACTIVE_LOW)
4643 set_bit(FLAG_ACTIVE_LOW, &desc->flags);
4645 if (lflags & GPIO_OPEN_DRAIN)
4646 set_bit(FLAG_OPEN_DRAIN, &desc->flags);
4647 else if (dflags & GPIOD_FLAGS_BIT_OPEN_DRAIN) {
4649 * This enforces open drain mode from the consumer side.
4650 * This is necessary for some busses like I2C, but the lookup
4651 * should *REALLY* have specified them as open drain in the
4652 * first place, so print a little warning here.
4654 set_bit(FLAG_OPEN_DRAIN, &desc->flags);
4656 "enforced open drain please flag it properly in DT/ACPI DSDT/board file\n");
4659 if (lflags & GPIO_OPEN_SOURCE)
4660 set_bit(FLAG_OPEN_SOURCE, &desc->flags);
4662 if ((lflags & GPIO_PULL_UP) && (lflags & GPIO_PULL_DOWN)) {
4664 "both pull-up and pull-down enabled, invalid configuration\n");
4668 if (lflags & GPIO_PULL_UP)
4669 set_bit(FLAG_PULL_UP, &desc->flags);
4670 else if (lflags & GPIO_PULL_DOWN)
4671 set_bit(FLAG_PULL_DOWN, &desc->flags);
4673 ret = gpiod_set_transitory(desc, (lflags & GPIO_TRANSITORY));
4677 /* No particular flag request, return here... */
4678 if (!(dflags & GPIOD_FLAGS_BIT_DIR_SET)) {
4679 pr_debug("no flags found for %s\n", con_id);
4684 if (dflags & GPIOD_FLAGS_BIT_DIR_OUT)
4685 ret = gpiod_direction_output(desc,
4686 !!(dflags & GPIOD_FLAGS_BIT_DIR_VAL));
4688 ret = gpiod_direction_input(desc);
4694 * gpiod_get_index - obtain a GPIO from a multi-index GPIO function
4695 * @dev: GPIO consumer, can be NULL for system-global GPIOs
4696 * @con_id: function within the GPIO consumer
4697 * @idx: index of the GPIO to obtain in the consumer
4698 * @flags: optional GPIO initialization flags
4700 * This variant of gpiod_get() allows to access GPIOs other than the first
4701 * defined one for functions that define several GPIOs.
4703 * Return a valid GPIO descriptor, -ENOENT if no GPIO has been assigned to the
4704 * requested function and/or index, or another IS_ERR() code if an error
4705 * occurred while trying to acquire the GPIO.
4707 struct gpio_desc *__must_check gpiod_get_index(struct device *dev,
4710 enum gpiod_flags flags)
4712 unsigned long lookupflags = GPIO_LOOKUP_FLAGS_DEFAULT;
4713 struct gpio_desc *desc = NULL;
4715 /* Maybe we have a device name, maybe not */
4716 const char *devname = dev ? dev_name(dev) : "?";
4718 dev_dbg(dev, "GPIO lookup for consumer %s\n", con_id);
4721 /* Using device tree? */
4722 if (IS_ENABLED(CONFIG_OF) && dev->of_node) {
4723 dev_dbg(dev, "using device tree for GPIO lookup\n");
4724 desc = of_find_gpio(dev, con_id, idx, &lookupflags);
4725 } else if (ACPI_COMPANION(dev)) {
4726 dev_dbg(dev, "using ACPI for GPIO lookup\n");
4727 desc = acpi_find_gpio(dev, con_id, idx, &flags, &lookupflags);
4732 * Either we are not using DT or ACPI, or their lookup did not return
4733 * a result. In that case, use platform lookup as a fallback.
4735 if (!desc || desc == ERR_PTR(-ENOENT)) {
4736 dev_dbg(dev, "using lookup tables for GPIO lookup\n");
4737 desc = gpiod_find(dev, con_id, idx, &lookupflags);
4741 dev_dbg(dev, "No GPIO consumer %s found\n", con_id);
4746 * If a connection label was passed use that, else attempt to use
4747 * the device name as label
4749 ret = gpiod_request(desc, con_id ? con_id : devname);
4751 if (ret == -EBUSY && flags & GPIOD_FLAGS_BIT_NONEXCLUSIVE) {
4753 * This happens when there are several consumers for
4754 * the same GPIO line: we just return here without
4755 * further initialization. It is a bit if a hack.
4756 * This is necessary to support fixed regulators.
4758 * FIXME: Make this more sane and safe.
4760 dev_info(dev, "nonexclusive access to GPIO for %s\n",
4761 con_id ? con_id : devname);
4764 return ERR_PTR(ret);
4768 ret = gpiod_configure_flags(desc, con_id, lookupflags, flags);
4770 dev_dbg(dev, "setup of GPIO %s failed\n", con_id);
4772 return ERR_PTR(ret);
4777 EXPORT_SYMBOL_GPL(gpiod_get_index);
4780 * fwnode_get_named_gpiod - obtain a GPIO from firmware node
4781 * @fwnode: handle of the firmware node
4782 * @propname: name of the firmware property representing the GPIO
4783 * @index: index of the GPIO to obtain for the consumer
4784 * @dflags: GPIO initialization flags
4785 * @label: label to attach to the requested GPIO
4787 * This function can be used for drivers that get their configuration
4788 * from opaque firmware.
4790 * The function properly finds the corresponding GPIO using whatever is the
4791 * underlying firmware interface and then makes sure that the GPIO
4792 * descriptor is requested before it is returned to the caller.
4795 * On successful request the GPIO pin is configured in accordance with
4798 * In case of error an ERR_PTR() is returned.
4800 struct gpio_desc *fwnode_get_named_gpiod(struct fwnode_handle *fwnode,
4801 const char *propname, int index,
4802 enum gpiod_flags dflags,
4805 unsigned long lflags = GPIO_LOOKUP_FLAGS_DEFAULT;
4806 struct gpio_desc *desc = ERR_PTR(-ENODEV);
4810 return ERR_PTR(-EINVAL);
4812 if (is_of_node(fwnode)) {
4813 desc = gpiod_get_from_of_node(to_of_node(fwnode),
4818 } else if (is_acpi_node(fwnode)) {
4819 struct acpi_gpio_info info;
4821 desc = acpi_node_get_gpiod(fwnode, propname, index, &info);
4825 acpi_gpio_update_gpiod_flags(&dflags, &info);
4826 acpi_gpio_update_gpiod_lookup_flags(&lflags, &info);
4829 /* Currently only ACPI takes this path */
4830 ret = gpiod_request(desc, label);
4832 return ERR_PTR(ret);
4834 ret = gpiod_configure_flags(desc, propname, lflags, dflags);
4837 return ERR_PTR(ret);
4842 EXPORT_SYMBOL_GPL(fwnode_get_named_gpiod);
4845 * gpiod_get_index_optional - obtain an optional GPIO from a multi-index GPIO
4847 * @dev: GPIO consumer, can be NULL for system-global GPIOs
4848 * @con_id: function within the GPIO consumer
4849 * @index: index of the GPIO to obtain in the consumer
4850 * @flags: optional GPIO initialization flags
4852 * This is equivalent to gpiod_get_index(), except that when no GPIO with the
4853 * specified index was assigned to the requested function it will return NULL.
4854 * This is convenient for drivers that need to handle optional GPIOs.
4856 struct gpio_desc *__must_check gpiod_get_index_optional(struct device *dev,
4859 enum gpiod_flags flags)
4861 struct gpio_desc *desc;
4863 desc = gpiod_get_index(dev, con_id, index, flags);
4865 if (PTR_ERR(desc) == -ENOENT)
4871 EXPORT_SYMBOL_GPL(gpiod_get_index_optional);
4874 * gpiod_hog - Hog the specified GPIO desc given the provided flags
4875 * @desc: gpio whose value will be assigned
4876 * @name: gpio line name
4877 * @lflags: bitmask of gpio_lookup_flags GPIO_* values - returned from
4878 * of_find_gpio() or of_get_gpio_hog()
4879 * @dflags: gpiod_flags - optional GPIO initialization flags
4881 int gpiod_hog(struct gpio_desc *desc, const char *name,
4882 unsigned long lflags, enum gpiod_flags dflags)
4884 struct gpio_chip *chip;
4885 struct gpio_desc *local_desc;
4889 chip = gpiod_to_chip(desc);
4890 hwnum = gpio_chip_hwgpio(desc);
4892 local_desc = gpiochip_request_own_desc(chip, hwnum, name,
4894 if (IS_ERR(local_desc)) {
4895 ret = PTR_ERR(local_desc);
4896 pr_err("requesting hog GPIO %s (chip %s, offset %d) failed, %d\n",
4897 name, chip->label, hwnum, ret);
4901 /* Mark GPIO as hogged so it can be identified and removed later */
4902 set_bit(FLAG_IS_HOGGED, &desc->flags);
4904 pr_info("GPIO line %d (%s) hogged as %s%s\n",
4905 desc_to_gpio(desc), name,
4906 (dflags & GPIOD_FLAGS_BIT_DIR_OUT) ? "output" : "input",
4907 (dflags & GPIOD_FLAGS_BIT_DIR_OUT) ?
4908 (dflags & GPIOD_FLAGS_BIT_DIR_VAL) ? "/high" : "/low" : "");
4914 * gpiochip_free_hogs - Scan gpio-controller chip and release GPIO hog
4915 * @chip: gpio chip to act on
4917 static void gpiochip_free_hogs(struct gpio_chip *chip)
4921 for (id = 0; id < chip->ngpio; id++) {
4922 if (test_bit(FLAG_IS_HOGGED, &chip->gpiodev->descs[id].flags))
4923 gpiochip_free_own_desc(&chip->gpiodev->descs[id]);
4928 * gpiod_get_array - obtain multiple GPIOs from a multi-index GPIO function
4929 * @dev: GPIO consumer, can be NULL for system-global GPIOs
4930 * @con_id: function within the GPIO consumer
4931 * @flags: optional GPIO initialization flags
4933 * This function acquires all the GPIOs defined under a given function.
4935 * Return a struct gpio_descs containing an array of descriptors, -ENOENT if
4936 * no GPIO has been assigned to the requested function, or another IS_ERR()
4937 * code if an error occurred while trying to acquire the GPIOs.
4939 struct gpio_descs *__must_check gpiod_get_array(struct device *dev,
4941 enum gpiod_flags flags)
4943 struct gpio_desc *desc;
4944 struct gpio_descs *descs;
4945 struct gpio_array *array_info = NULL;
4946 struct gpio_chip *chip;
4947 int count, bitmap_size;
4949 count = gpiod_count(dev, con_id);
4951 return ERR_PTR(count);
4953 descs = kzalloc(struct_size(descs, desc, count), GFP_KERNEL);
4955 return ERR_PTR(-ENOMEM);
4957 for (descs->ndescs = 0; descs->ndescs < count; ) {
4958 desc = gpiod_get_index(dev, con_id, descs->ndescs, flags);
4960 gpiod_put_array(descs);
4961 return ERR_CAST(desc);
4964 descs->desc[descs->ndescs] = desc;
4966 chip = gpiod_to_chip(desc);
4968 * If pin hardware number of array member 0 is also 0, select
4969 * its chip as a candidate for fast bitmap processing path.
4971 if (descs->ndescs == 0 && gpio_chip_hwgpio(desc) == 0) {
4972 struct gpio_descs *array;
4974 bitmap_size = BITS_TO_LONGS(chip->ngpio > count ?
4975 chip->ngpio : count);
4977 array = kzalloc(struct_size(descs, desc, count) +
4978 struct_size(array_info, invert_mask,
4979 3 * bitmap_size), GFP_KERNEL);
4981 gpiod_put_array(descs);
4982 return ERR_PTR(-ENOMEM);
4985 memcpy(array, descs,
4986 struct_size(descs, desc, descs->ndescs + 1));
4990 array_info = (void *)(descs->desc + count);
4991 array_info->get_mask = array_info->invert_mask +
4993 array_info->set_mask = array_info->get_mask +
4996 array_info->desc = descs->desc;
4997 array_info->size = count;
4998 array_info->chip = chip;
4999 bitmap_set(array_info->get_mask, descs->ndescs,
5000 count - descs->ndescs);
5001 bitmap_set(array_info->set_mask, descs->ndescs,
5002 count - descs->ndescs);
5003 descs->info = array_info;
5005 /* Unmark array members which don't belong to the 'fast' chip */
5006 if (array_info && array_info->chip != chip) {
5007 __clear_bit(descs->ndescs, array_info->get_mask);
5008 __clear_bit(descs->ndescs, array_info->set_mask);
5011 * Detect array members which belong to the 'fast' chip
5012 * but their pins are not in hardware order.
5014 else if (array_info &&
5015 gpio_chip_hwgpio(desc) != descs->ndescs) {
5017 * Don't use fast path if all array members processed so
5018 * far belong to the same chip as this one but its pin
5019 * hardware number is different from its array index.
5021 if (bitmap_full(array_info->get_mask, descs->ndescs)) {
5024 __clear_bit(descs->ndescs,
5025 array_info->get_mask);
5026 __clear_bit(descs->ndescs,
5027 array_info->set_mask);
5029 } else if (array_info) {
5030 /* Exclude open drain or open source from fast output */
5031 if (gpiochip_line_is_open_drain(chip, descs->ndescs) ||
5032 gpiochip_line_is_open_source(chip, descs->ndescs))
5033 __clear_bit(descs->ndescs,
5034 array_info->set_mask);
5035 /* Identify 'fast' pins which require invertion */
5036 if (gpiod_is_active_low(desc))
5037 __set_bit(descs->ndescs,
5038 array_info->invert_mask);
5045 "GPIO array info: chip=%s, size=%d, get_mask=%lx, set_mask=%lx, invert_mask=%lx\n",
5046 array_info->chip->label, array_info->size,
5047 *array_info->get_mask, *array_info->set_mask,
5048 *array_info->invert_mask);
5051 EXPORT_SYMBOL_GPL(gpiod_get_array);
5054 * gpiod_get_array_optional - obtain multiple GPIOs from a multi-index GPIO
5056 * @dev: GPIO consumer, can be NULL for system-global GPIOs
5057 * @con_id: function within the GPIO consumer
5058 * @flags: optional GPIO initialization flags
5060 * This is equivalent to gpiod_get_array(), except that when no GPIO was
5061 * assigned to the requested function it will return NULL.
5063 struct gpio_descs *__must_check gpiod_get_array_optional(struct device *dev,
5065 enum gpiod_flags flags)
5067 struct gpio_descs *descs;
5069 descs = gpiod_get_array(dev, con_id, flags);
5070 if (PTR_ERR(descs) == -ENOENT)
5075 EXPORT_SYMBOL_GPL(gpiod_get_array_optional);
5078 * gpiod_put - dispose of a GPIO descriptor
5079 * @desc: GPIO descriptor to dispose of
5081 * No descriptor can be used after gpiod_put() has been called on it.
5083 void gpiod_put(struct gpio_desc *desc)
5088 EXPORT_SYMBOL_GPL(gpiod_put);
5091 * gpiod_put_array - dispose of multiple GPIO descriptors
5092 * @descs: struct gpio_descs containing an array of descriptors
5094 void gpiod_put_array(struct gpio_descs *descs)
5098 for (i = 0; i < descs->ndescs; i++)
5099 gpiod_put(descs->desc[i]);
5103 EXPORT_SYMBOL_GPL(gpiod_put_array);
5105 static int __init gpiolib_dev_init(void)
5109 /* Register GPIO sysfs bus */
5110 ret = bus_register(&gpio_bus_type);
5112 pr_err("gpiolib: could not register GPIO bus type\n");
5116 ret = alloc_chrdev_region(&gpio_devt, 0, GPIO_DEV_MAX, GPIOCHIP_NAME);
5118 pr_err("gpiolib: failed to allocate char dev region\n");
5119 bus_unregister(&gpio_bus_type);
5121 gpiolib_initialized = true;
5122 gpiochip_setup_devs();
5126 core_initcall(gpiolib_dev_init);
5128 #ifdef CONFIG_DEBUG_FS
5130 static void gpiolib_dbg_show(struct seq_file *s, struct gpio_device *gdev)
5133 struct gpio_chip *chip = gdev->chip;
5134 unsigned gpio = gdev->base;
5135 struct gpio_desc *gdesc = &gdev->descs[0];
5140 for (i = 0; i < gdev->ngpio; i++, gpio++, gdesc++) {
5141 if (!test_bit(FLAG_REQUESTED, &gdesc->flags)) {
5143 seq_printf(s, " gpio-%-3d (%-20.20s)\n",
5149 gpiod_get_direction(gdesc);
5150 is_out = test_bit(FLAG_IS_OUT, &gdesc->flags);
5151 is_irq = test_bit(FLAG_USED_AS_IRQ, &gdesc->flags);
5152 active_low = test_bit(FLAG_ACTIVE_LOW, &gdesc->flags);
5153 seq_printf(s, " gpio-%-3d (%-20.20s|%-20.20s) %s %s %s%s",
5154 gpio, gdesc->name ? gdesc->name : "", gdesc->label,
5155 is_out ? "out" : "in ",
5156 chip->get ? (chip->get(chip, i) ? "hi" : "lo") : "? ",
5157 is_irq ? "IRQ " : "",
5158 active_low ? "ACTIVE LOW" : "");
5159 seq_printf(s, "\n");
5163 static void *gpiolib_seq_start(struct seq_file *s, loff_t *pos)
5165 unsigned long flags;
5166 struct gpio_device *gdev = NULL;
5167 loff_t index = *pos;
5171 spin_lock_irqsave(&gpio_lock, flags);
5172 list_for_each_entry(gdev, &gpio_devices, list)
5174 spin_unlock_irqrestore(&gpio_lock, flags);
5177 spin_unlock_irqrestore(&gpio_lock, flags);
5182 static void *gpiolib_seq_next(struct seq_file *s, void *v, loff_t *pos)
5184 unsigned long flags;
5185 struct gpio_device *gdev = v;
5188 spin_lock_irqsave(&gpio_lock, flags);
5189 if (list_is_last(&gdev->list, &gpio_devices))
5192 ret = list_entry(gdev->list.next, struct gpio_device, list);
5193 spin_unlock_irqrestore(&gpio_lock, flags);
5201 static void gpiolib_seq_stop(struct seq_file *s, void *v)
5205 static int gpiolib_seq_show(struct seq_file *s, void *v)
5207 struct gpio_device *gdev = v;
5208 struct gpio_chip *chip = gdev->chip;
5209 struct device *parent;
5212 seq_printf(s, "%s%s: (dangling chip)", (char *)s->private,
5213 dev_name(&gdev->dev));
5217 seq_printf(s, "%s%s: GPIOs %d-%d", (char *)s->private,
5218 dev_name(&gdev->dev),
5219 gdev->base, gdev->base + gdev->ngpio - 1);
5220 parent = chip->parent;
5222 seq_printf(s, ", parent: %s/%s",
5223 parent->bus ? parent->bus->name : "no-bus",
5226 seq_printf(s, ", %s", chip->label);
5227 if (chip->can_sleep)
5228 seq_printf(s, ", can sleep");
5229 seq_printf(s, ":\n");
5232 chip->dbg_show(s, chip);
5234 gpiolib_dbg_show(s, gdev);
5239 static const struct seq_operations gpiolib_seq_ops = {
5240 .start = gpiolib_seq_start,
5241 .next = gpiolib_seq_next,
5242 .stop = gpiolib_seq_stop,
5243 .show = gpiolib_seq_show,
5246 static int gpiolib_open(struct inode *inode, struct file *file)
5248 return seq_open(file, &gpiolib_seq_ops);
5251 static const struct file_operations gpiolib_operations = {
5252 .owner = THIS_MODULE,
5253 .open = gpiolib_open,
5255 .llseek = seq_lseek,
5256 .release = seq_release,
5259 static int __init gpiolib_debugfs_init(void)
5261 /* /sys/kernel/debug/gpio */
5262 debugfs_create_file("gpio", S_IFREG | S_IRUGO, NULL, NULL,
5263 &gpiolib_operations);
5266 subsys_initcall(gpiolib_debugfs_init);
5268 #endif /* DEBUG_FS */