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];
154 * desc_to_gpio - convert a GPIO descriptor to the integer namespace
155 * @desc: GPIO descriptor
157 * This should disappear in the future but is needed since we still
158 * use GPIO numbers for error messages and sysfs nodes.
161 * The global GPIO number for the GPIO specified by its descriptor.
163 int desc_to_gpio(const struct gpio_desc *desc)
165 return desc->gdev->base + (desc - &desc->gdev->descs[0]);
167 EXPORT_SYMBOL_GPL(desc_to_gpio);
171 * gpiod_to_chip - Return the GPIO chip to which a GPIO descriptor belongs
172 * @desc: descriptor to return the chip of
174 struct gpio_chip *gpiod_to_chip(const struct gpio_desc *desc)
176 if (!desc || !desc->gdev)
178 return desc->gdev->chip;
180 EXPORT_SYMBOL_GPL(gpiod_to_chip);
182 /* dynamic allocation of GPIOs, e.g. on a hotplugged device */
183 static int gpiochip_find_base(int ngpio)
185 struct gpio_device *gdev;
186 int base = ARCH_NR_GPIOS - ngpio;
188 list_for_each_entry_reverse(gdev, &gpio_devices, list) {
189 /* found a free space? */
190 if (gdev->base + gdev->ngpio <= base)
193 /* nope, check the space right before the chip */
194 base = gdev->base - ngpio;
197 if (gpio_is_valid(base)) {
198 pr_debug("%s: found new base at %d\n", __func__, base);
201 pr_err("%s: cannot find free range\n", __func__);
207 * gpiod_get_direction - return the current direction of a GPIO
208 * @desc: GPIO to get the direction of
210 * Returns 0 for output, 1 for input, or an error code in case of error.
212 * This function may sleep if gpiod_cansleep() is true.
214 int gpiod_get_direction(struct gpio_desc *desc)
216 struct gpio_chip *chip;
220 chip = gpiod_to_chip(desc);
221 offset = gpio_chip_hwgpio(desc);
224 * Open drain emulation using input mode may incorrectly report
225 * input here, fix that up.
227 if (test_bit(FLAG_OPEN_DRAIN, &desc->flags) &&
228 test_bit(FLAG_IS_OUT, &desc->flags))
231 if (!chip->get_direction)
234 ret = chip->get_direction(chip, offset);
238 /* GPIOF_DIR_IN or other positive, otherwise GPIOF_DIR_OUT */
242 assign_bit(FLAG_IS_OUT, &desc->flags, !ret);
246 EXPORT_SYMBOL_GPL(gpiod_get_direction);
249 * Add a new chip to the global chips list, keeping the list of chips sorted
250 * by range(means [base, base + ngpio - 1]) order.
252 * Return -EBUSY if the new chip overlaps with some other chip's integer
255 static int gpiodev_add_to_list(struct gpio_device *gdev)
257 struct gpio_device *prev, *next;
259 if (list_empty(&gpio_devices)) {
260 /* initial entry in list */
261 list_add_tail(&gdev->list, &gpio_devices);
265 next = list_entry(gpio_devices.next, struct gpio_device, list);
266 if (gdev->base + gdev->ngpio <= next->base) {
267 /* add before first entry */
268 list_add(&gdev->list, &gpio_devices);
272 prev = list_entry(gpio_devices.prev, struct gpio_device, list);
273 if (prev->base + prev->ngpio <= gdev->base) {
274 /* add behind last entry */
275 list_add_tail(&gdev->list, &gpio_devices);
279 list_for_each_entry_safe(prev, next, &gpio_devices, list) {
280 /* at the end of the list */
281 if (&next->list == &gpio_devices)
284 /* add between prev and next */
285 if (prev->base + prev->ngpio <= gdev->base
286 && gdev->base + gdev->ngpio <= next->base) {
287 list_add(&gdev->list, &prev->list);
292 dev_err(&gdev->dev, "GPIO integer space overlap, cannot add chip\n");
297 * Convert a GPIO name to its descriptor
299 static struct gpio_desc *gpio_name_to_desc(const char * const name)
301 struct gpio_device *gdev;
304 spin_lock_irqsave(&gpio_lock, flags);
306 list_for_each_entry(gdev, &gpio_devices, list) {
309 for (i = 0; i != gdev->ngpio; ++i) {
310 struct gpio_desc *desc = &gdev->descs[i];
312 if (!desc->name || !name)
315 if (!strcmp(desc->name, name)) {
316 spin_unlock_irqrestore(&gpio_lock, flags);
322 spin_unlock_irqrestore(&gpio_lock, flags);
328 * Takes the names from gc->names and checks if they are all unique. If they
329 * are, they are assigned to their gpio descriptors.
331 * Warning if one of the names is already used for a different GPIO.
333 static int gpiochip_set_desc_names(struct gpio_chip *gc)
335 struct gpio_device *gdev = gc->gpiodev;
341 /* First check all names if they are unique */
342 for (i = 0; i != gc->ngpio; ++i) {
343 struct gpio_desc *gpio;
345 gpio = gpio_name_to_desc(gc->names[i]);
348 "Detected name collision for GPIO name '%s'\n",
352 /* Then add all names to the GPIO descriptors */
353 for (i = 0; i != gc->ngpio; ++i)
354 gdev->descs[i].name = gc->names[i];
359 static unsigned long *gpiochip_allocate_mask(struct gpio_chip *chip)
363 p = bitmap_alloc(chip->ngpio, GFP_KERNEL);
367 /* Assume by default all GPIOs are valid */
368 bitmap_fill(p, chip->ngpio);
373 static int gpiochip_alloc_valid_mask(struct gpio_chip *gc)
375 if (!(of_gpio_need_valid_mask(gc) || gc->init_valid_mask))
378 gc->valid_mask = gpiochip_allocate_mask(gc);
385 static int gpiochip_init_valid_mask(struct gpio_chip *gc)
387 if (gc->init_valid_mask)
388 return gc->init_valid_mask(gc,
395 static void gpiochip_free_valid_mask(struct gpio_chip *gpiochip)
397 bitmap_free(gpiochip->valid_mask);
398 gpiochip->valid_mask = NULL;
401 static int gpiochip_add_pin_ranges(struct gpio_chip *gc)
403 if (gc->add_pin_ranges)
404 return gc->add_pin_ranges(gc);
409 bool gpiochip_line_is_valid(const struct gpio_chip *gpiochip,
412 /* No mask means all valid */
413 if (likely(!gpiochip->valid_mask))
415 return test_bit(offset, gpiochip->valid_mask);
417 EXPORT_SYMBOL_GPL(gpiochip_line_is_valid);
420 * GPIO line handle management
424 * struct linehandle_state - contains the state of a userspace handle
425 * @gdev: the GPIO device the handle pertains to
426 * @label: consumer label used to tag descriptors
427 * @descs: the GPIO descriptors held by this handle
428 * @numdescs: the number of descriptors held in the descs array
430 struct linehandle_state {
431 struct gpio_device *gdev;
433 struct gpio_desc *descs[GPIOHANDLES_MAX];
437 #define GPIOHANDLE_REQUEST_VALID_FLAGS \
438 (GPIOHANDLE_REQUEST_INPUT | \
439 GPIOHANDLE_REQUEST_OUTPUT | \
440 GPIOHANDLE_REQUEST_ACTIVE_LOW | \
441 GPIOHANDLE_REQUEST_BIAS_PULL_UP | \
442 GPIOHANDLE_REQUEST_BIAS_PULL_DOWN | \
443 GPIOHANDLE_REQUEST_BIAS_DISABLE | \
444 GPIOHANDLE_REQUEST_OPEN_DRAIN | \
445 GPIOHANDLE_REQUEST_OPEN_SOURCE)
447 static int linehandle_validate_flags(u32 flags)
449 /* Return an error if an unknown flag is set */
450 if (flags & ~GPIOHANDLE_REQUEST_VALID_FLAGS)
454 * Do not allow both INPUT & OUTPUT flags to be set as they are
457 if ((flags & GPIOHANDLE_REQUEST_INPUT) &&
458 (flags & GPIOHANDLE_REQUEST_OUTPUT))
462 * Do not allow OPEN_SOURCE & OPEN_DRAIN flags in a single request. If
463 * the hardware actually supports enabling both at the same time the
464 * electrical result would be disastrous.
466 if ((flags & GPIOHANDLE_REQUEST_OPEN_DRAIN) &&
467 (flags & GPIOHANDLE_REQUEST_OPEN_SOURCE))
470 /* OPEN_DRAIN and OPEN_SOURCE flags only make sense for output mode. */
471 if (!(flags & GPIOHANDLE_REQUEST_OUTPUT) &&
472 ((flags & GPIOHANDLE_REQUEST_OPEN_DRAIN) ||
473 (flags & GPIOHANDLE_REQUEST_OPEN_SOURCE)))
476 /* Bias flags only allowed for input or output mode. */
477 if (!((flags & GPIOHANDLE_REQUEST_INPUT) ||
478 (flags & GPIOHANDLE_REQUEST_OUTPUT)) &&
479 ((flags & GPIOHANDLE_REQUEST_BIAS_DISABLE) ||
480 (flags & GPIOHANDLE_REQUEST_BIAS_PULL_UP) ||
481 (flags & GPIOHANDLE_REQUEST_BIAS_PULL_DOWN)))
484 /* Only one bias flag can be set. */
485 if (((flags & GPIOHANDLE_REQUEST_BIAS_DISABLE) &&
486 (flags & (GPIOHANDLE_REQUEST_BIAS_PULL_DOWN |
487 GPIOHANDLE_REQUEST_BIAS_PULL_UP))) ||
488 ((flags & GPIOHANDLE_REQUEST_BIAS_PULL_DOWN) &&
489 (flags & GPIOHANDLE_REQUEST_BIAS_PULL_UP)))
495 static long linehandle_set_config(struct linehandle_state *lh,
498 struct gpiohandle_config gcnf;
499 struct gpio_desc *desc;
502 unsigned long *flagsp;
504 if (copy_from_user(&gcnf, ip, sizeof(gcnf)))
508 ret = linehandle_validate_flags(lflags);
512 for (i = 0; i < lh->numdescs; i++) {
514 flagsp = &desc->flags;
516 assign_bit(FLAG_ACTIVE_LOW, flagsp,
517 lflags & GPIOHANDLE_REQUEST_ACTIVE_LOW);
519 assign_bit(FLAG_OPEN_DRAIN, flagsp,
520 lflags & GPIOHANDLE_REQUEST_OPEN_DRAIN);
522 assign_bit(FLAG_OPEN_SOURCE, flagsp,
523 lflags & GPIOHANDLE_REQUEST_OPEN_SOURCE);
525 assign_bit(FLAG_PULL_UP, flagsp,
526 lflags & GPIOHANDLE_REQUEST_BIAS_PULL_UP);
528 assign_bit(FLAG_PULL_DOWN, flagsp,
529 lflags & GPIOHANDLE_REQUEST_BIAS_PULL_DOWN);
531 assign_bit(FLAG_BIAS_DISABLE, flagsp,
532 lflags & GPIOHANDLE_REQUEST_BIAS_DISABLE);
535 * Lines have to be requested explicitly for input
536 * or output, else the line will be treated "as is".
538 if (lflags & GPIOHANDLE_REQUEST_OUTPUT) {
539 int val = !!gcnf.default_values[i];
541 ret = gpiod_direction_output(desc, val);
544 } else if (lflags & GPIOHANDLE_REQUEST_INPUT) {
545 ret = gpiod_direction_input(desc);
553 static long linehandle_ioctl(struct file *filep, unsigned int cmd,
556 struct linehandle_state *lh = filep->private_data;
557 void __user *ip = (void __user *)arg;
558 struct gpiohandle_data ghd;
559 DECLARE_BITMAP(vals, GPIOHANDLES_MAX);
562 if (cmd == GPIOHANDLE_GET_LINE_VALUES_IOCTL) {
563 /* NOTE: It's ok to read values of output lines. */
564 int ret = gpiod_get_array_value_complex(false,
573 memset(&ghd, 0, sizeof(ghd));
574 for (i = 0; i < lh->numdescs; i++)
575 ghd.values[i] = test_bit(i, vals);
577 if (copy_to_user(ip, &ghd, sizeof(ghd)))
581 } else if (cmd == GPIOHANDLE_SET_LINE_VALUES_IOCTL) {
583 * All line descriptors were created at once with the same
584 * flags so just check if the first one is really output.
586 if (!test_bit(FLAG_IS_OUT, &lh->descs[0]->flags))
589 if (copy_from_user(&ghd, ip, sizeof(ghd)))
592 /* Clamp all values to [0,1] */
593 for (i = 0; i < lh->numdescs; i++)
594 __assign_bit(i, vals, ghd.values[i]);
596 /* Reuse the array setting function */
597 return gpiod_set_array_value_complex(false,
603 } else if (cmd == GPIOHANDLE_SET_CONFIG_IOCTL) {
604 return linehandle_set_config(lh, ip);
610 static long linehandle_ioctl_compat(struct file *filep, unsigned int cmd,
613 return linehandle_ioctl(filep, cmd, (unsigned long)compat_ptr(arg));
617 static int linehandle_release(struct inode *inode, struct file *filep)
619 struct linehandle_state *lh = filep->private_data;
620 struct gpio_device *gdev = lh->gdev;
623 for (i = 0; i < lh->numdescs; i++)
624 gpiod_free(lh->descs[i]);
627 put_device(&gdev->dev);
631 static const struct file_operations linehandle_fileops = {
632 .release = linehandle_release,
633 .owner = THIS_MODULE,
634 .llseek = noop_llseek,
635 .unlocked_ioctl = linehandle_ioctl,
637 .compat_ioctl = linehandle_ioctl_compat,
641 static int linehandle_create(struct gpio_device *gdev, void __user *ip)
643 struct gpiohandle_request handlereq;
644 struct linehandle_state *lh;
646 int fd, i, count = 0, ret;
649 if (copy_from_user(&handlereq, ip, sizeof(handlereq)))
651 if ((handlereq.lines == 0) || (handlereq.lines > GPIOHANDLES_MAX))
654 lflags = handlereq.flags;
656 ret = linehandle_validate_flags(lflags);
660 lh = kzalloc(sizeof(*lh), GFP_KERNEL);
664 get_device(&gdev->dev);
666 /* Make sure this is terminated */
667 handlereq.consumer_label[sizeof(handlereq.consumer_label)-1] = '\0';
668 if (strlen(handlereq.consumer_label)) {
669 lh->label = kstrdup(handlereq.consumer_label,
677 /* Request each GPIO */
678 for (i = 0; i < handlereq.lines; i++) {
679 u32 offset = handlereq.lineoffsets[i];
680 struct gpio_desc *desc = gpiochip_get_desc(gdev->chip, offset);
687 ret = gpiod_request(desc, lh->label);
693 if (lflags & GPIOHANDLE_REQUEST_ACTIVE_LOW)
694 set_bit(FLAG_ACTIVE_LOW, &desc->flags);
695 if (lflags & GPIOHANDLE_REQUEST_OPEN_DRAIN)
696 set_bit(FLAG_OPEN_DRAIN, &desc->flags);
697 if (lflags & GPIOHANDLE_REQUEST_OPEN_SOURCE)
698 set_bit(FLAG_OPEN_SOURCE, &desc->flags);
699 if (lflags & GPIOHANDLE_REQUEST_BIAS_DISABLE)
700 set_bit(FLAG_BIAS_DISABLE, &desc->flags);
701 if (lflags & GPIOHANDLE_REQUEST_BIAS_PULL_DOWN)
702 set_bit(FLAG_PULL_DOWN, &desc->flags);
703 if (lflags & GPIOHANDLE_REQUEST_BIAS_PULL_UP)
704 set_bit(FLAG_PULL_UP, &desc->flags);
706 ret = gpiod_set_transitory(desc, false);
711 * Lines have to be requested explicitly for input
712 * or output, else the line will be treated "as is".
714 if (lflags & GPIOHANDLE_REQUEST_OUTPUT) {
715 int val = !!handlereq.default_values[i];
717 ret = gpiod_direction_output(desc, val);
720 } else if (lflags & GPIOHANDLE_REQUEST_INPUT) {
721 ret = gpiod_direction_input(desc);
725 dev_dbg(&gdev->dev, "registered chardev handle for line %d\n",
728 /* Let i point at the last handle */
730 lh->numdescs = handlereq.lines;
732 fd = get_unused_fd_flags(O_RDONLY | O_CLOEXEC);
738 file = anon_inode_getfile("gpio-linehandle",
741 O_RDONLY | O_CLOEXEC);
744 goto out_put_unused_fd;
748 if (copy_to_user(ip, &handlereq, sizeof(handlereq))) {
750 * fput() will trigger the release() callback, so do not go onto
751 * the regular error cleanup path here.
758 fd_install(fd, file);
760 dev_dbg(&gdev->dev, "registered chardev handle for %d lines\n",
768 for (i = 0; i < count; i++)
769 gpiod_free(lh->descs[i]);
773 put_device(&gdev->dev);
778 * GPIO line event management
782 * struct lineevent_state - contains the state of a userspace event
783 * @gdev: the GPIO device the event pertains to
784 * @label: consumer label used to tag descriptors
785 * @desc: the GPIO descriptor held by this event
786 * @eflags: the event flags this line was requested with
787 * @irq: the interrupt that trigger in response to events on this GPIO
788 * @wait: wait queue that handles blocking reads of events
789 * @events: KFIFO for the GPIO events
790 * @read_lock: mutex lock to protect reads from colliding with adding
791 * new events to the FIFO
792 * @timestamp: cache for the timestamp storing it between hardirq
793 * and IRQ thread, used to bring the timestamp close to the actual
796 struct lineevent_state {
797 struct gpio_device *gdev;
799 struct gpio_desc *desc;
802 wait_queue_head_t wait;
803 DECLARE_KFIFO(events, struct gpioevent_data, 16);
804 struct mutex read_lock;
808 #define GPIOEVENT_REQUEST_VALID_FLAGS \
809 (GPIOEVENT_REQUEST_RISING_EDGE | \
810 GPIOEVENT_REQUEST_FALLING_EDGE)
812 static __poll_t lineevent_poll(struct file *filep,
813 struct poll_table_struct *wait)
815 struct lineevent_state *le = filep->private_data;
818 poll_wait(filep, &le->wait, wait);
820 if (!kfifo_is_empty(&le->events))
821 events = EPOLLIN | EPOLLRDNORM;
827 static ssize_t lineevent_read(struct file *filep,
832 struct lineevent_state *le = filep->private_data;
836 if (count < sizeof(struct gpioevent_data))
840 if (kfifo_is_empty(&le->events)) {
841 if (filep->f_flags & O_NONBLOCK)
844 ret = wait_event_interruptible(le->wait,
845 !kfifo_is_empty(&le->events));
850 if (mutex_lock_interruptible(&le->read_lock))
852 ret = kfifo_to_user(&le->events, buf, count, &copied);
853 mutex_unlock(&le->read_lock);
859 * If we couldn't read anything from the fifo (a different
860 * thread might have been faster) we either return -EAGAIN if
861 * the file descriptor is non-blocking, otherwise we go back to
862 * sleep and wait for more data to arrive.
864 if (copied == 0 && (filep->f_flags & O_NONBLOCK))
867 } while (copied == 0);
872 static int lineevent_release(struct inode *inode, struct file *filep)
874 struct lineevent_state *le = filep->private_data;
875 struct gpio_device *gdev = le->gdev;
877 free_irq(le->irq, le);
878 gpiod_free(le->desc);
881 put_device(&gdev->dev);
885 static long lineevent_ioctl(struct file *filep, unsigned int cmd,
888 struct lineevent_state *le = filep->private_data;
889 void __user *ip = (void __user *)arg;
890 struct gpiohandle_data ghd;
893 * We can get the value for an event line but not set it,
894 * because it is input by definition.
896 if (cmd == GPIOHANDLE_GET_LINE_VALUES_IOCTL) {
899 memset(&ghd, 0, sizeof(ghd));
901 val = gpiod_get_value_cansleep(le->desc);
906 if (copy_to_user(ip, &ghd, sizeof(ghd)))
915 static long lineevent_ioctl_compat(struct file *filep, unsigned int cmd,
918 return lineevent_ioctl(filep, cmd, (unsigned long)compat_ptr(arg));
922 static const struct file_operations lineevent_fileops = {
923 .release = lineevent_release,
924 .read = lineevent_read,
925 .poll = lineevent_poll,
926 .owner = THIS_MODULE,
927 .llseek = noop_llseek,
928 .unlocked_ioctl = lineevent_ioctl,
930 .compat_ioctl = lineevent_ioctl_compat,
934 static irqreturn_t lineevent_irq_thread(int irq, void *p)
936 struct lineevent_state *le = p;
937 struct gpioevent_data ge;
940 /* Do not leak kernel stack to userspace */
941 memset(&ge, 0, sizeof(ge));
944 * We may be running from a nested threaded interrupt in which case
945 * we didn't get the timestamp from lineevent_irq_handler().
948 ge.timestamp = ktime_get_real_ns();
950 ge.timestamp = le->timestamp;
952 if (le->eflags & GPIOEVENT_REQUEST_RISING_EDGE
953 && le->eflags & GPIOEVENT_REQUEST_FALLING_EDGE) {
954 int level = gpiod_get_value_cansleep(le->desc);
956 /* Emit low-to-high event */
957 ge.id = GPIOEVENT_EVENT_RISING_EDGE;
959 /* Emit high-to-low event */
960 ge.id = GPIOEVENT_EVENT_FALLING_EDGE;
961 } else if (le->eflags & GPIOEVENT_REQUEST_RISING_EDGE) {
962 /* Emit low-to-high event */
963 ge.id = GPIOEVENT_EVENT_RISING_EDGE;
964 } else if (le->eflags & GPIOEVENT_REQUEST_FALLING_EDGE) {
965 /* Emit high-to-low event */
966 ge.id = GPIOEVENT_EVENT_FALLING_EDGE;
971 ret = kfifo_put(&le->events, ge);
973 wake_up_poll(&le->wait, EPOLLIN);
978 static irqreturn_t lineevent_irq_handler(int irq, void *p)
980 struct lineevent_state *le = p;
983 * Just store the timestamp in hardirq context so we get it as
984 * close in time as possible to the actual event.
986 le->timestamp = ktime_get_real_ns();
988 return IRQ_WAKE_THREAD;
991 static int lineevent_create(struct gpio_device *gdev, void __user *ip)
993 struct gpioevent_request eventreq;
994 struct lineevent_state *le;
995 struct gpio_desc *desc;
1004 if (copy_from_user(&eventreq, ip, sizeof(eventreq)))
1007 offset = eventreq.lineoffset;
1008 lflags = eventreq.handleflags;
1009 eflags = eventreq.eventflags;
1011 desc = gpiochip_get_desc(gdev->chip, offset);
1013 return PTR_ERR(desc);
1015 /* Return an error if a unknown flag is set */
1016 if ((lflags & ~GPIOHANDLE_REQUEST_VALID_FLAGS) ||
1017 (eflags & ~GPIOEVENT_REQUEST_VALID_FLAGS))
1020 /* This is just wrong: we don't look for events on output lines */
1021 if ((lflags & GPIOHANDLE_REQUEST_OUTPUT) ||
1022 (lflags & GPIOHANDLE_REQUEST_OPEN_DRAIN) ||
1023 (lflags & GPIOHANDLE_REQUEST_OPEN_SOURCE))
1026 /* Only one bias flag can be set. */
1027 if (((lflags & GPIOHANDLE_REQUEST_BIAS_DISABLE) &&
1028 (lflags & (GPIOHANDLE_REQUEST_BIAS_PULL_DOWN |
1029 GPIOHANDLE_REQUEST_BIAS_PULL_UP))) ||
1030 ((lflags & GPIOHANDLE_REQUEST_BIAS_PULL_DOWN) &&
1031 (lflags & GPIOHANDLE_REQUEST_BIAS_PULL_UP)))
1034 le = kzalloc(sizeof(*le), GFP_KERNEL);
1038 get_device(&gdev->dev);
1040 /* Make sure this is terminated */
1041 eventreq.consumer_label[sizeof(eventreq.consumer_label)-1] = '\0';
1042 if (strlen(eventreq.consumer_label)) {
1043 le->label = kstrdup(eventreq.consumer_label,
1051 ret = gpiod_request(desc, le->label);
1053 goto out_free_label;
1055 le->eflags = eflags;
1057 if (lflags & GPIOHANDLE_REQUEST_ACTIVE_LOW)
1058 set_bit(FLAG_ACTIVE_LOW, &desc->flags);
1059 if (lflags & GPIOHANDLE_REQUEST_BIAS_DISABLE)
1060 set_bit(FLAG_BIAS_DISABLE, &desc->flags);
1061 if (lflags & GPIOHANDLE_REQUEST_BIAS_PULL_DOWN)
1062 set_bit(FLAG_PULL_DOWN, &desc->flags);
1063 if (lflags & GPIOHANDLE_REQUEST_BIAS_PULL_UP)
1064 set_bit(FLAG_PULL_UP, &desc->flags);
1066 ret = gpiod_direction_input(desc);
1070 le->irq = gpiod_to_irq(desc);
1076 if (eflags & GPIOEVENT_REQUEST_RISING_EDGE)
1077 irqflags |= test_bit(FLAG_ACTIVE_LOW, &desc->flags) ?
1078 IRQF_TRIGGER_FALLING : IRQF_TRIGGER_RISING;
1079 if (eflags & GPIOEVENT_REQUEST_FALLING_EDGE)
1080 irqflags |= test_bit(FLAG_ACTIVE_LOW, &desc->flags) ?
1081 IRQF_TRIGGER_RISING : IRQF_TRIGGER_FALLING;
1082 irqflags |= IRQF_ONESHOT;
1084 INIT_KFIFO(le->events);
1085 init_waitqueue_head(&le->wait);
1086 mutex_init(&le->read_lock);
1088 /* Request a thread to read the events */
1089 ret = request_threaded_irq(le->irq,
1090 lineevent_irq_handler,
1091 lineevent_irq_thread,
1098 fd = get_unused_fd_flags(O_RDONLY | O_CLOEXEC);
1104 file = anon_inode_getfile("gpio-event",
1107 O_RDONLY | O_CLOEXEC);
1109 ret = PTR_ERR(file);
1110 goto out_put_unused_fd;
1114 if (copy_to_user(ip, &eventreq, sizeof(eventreq))) {
1116 * fput() will trigger the release() callback, so do not go onto
1117 * the regular error cleanup path here.
1124 fd_install(fd, file);
1131 free_irq(le->irq, le);
1133 gpiod_free(le->desc);
1138 put_device(&gdev->dev);
1143 * gpio_ioctl() - ioctl handler for the GPIO chardev
1145 static long gpio_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
1147 struct gpio_device *gdev = filp->private_data;
1148 struct gpio_chip *chip = gdev->chip;
1149 void __user *ip = (void __user *)arg;
1151 /* We fail any subsequent ioctl():s when the chip is gone */
1155 /* Fill in the struct and pass to userspace */
1156 if (cmd == GPIO_GET_CHIPINFO_IOCTL) {
1157 struct gpiochip_info chipinfo;
1159 memset(&chipinfo, 0, sizeof(chipinfo));
1161 strncpy(chipinfo.name, dev_name(&gdev->dev),
1162 sizeof(chipinfo.name));
1163 chipinfo.name[sizeof(chipinfo.name)-1] = '\0';
1164 strncpy(chipinfo.label, gdev->label,
1165 sizeof(chipinfo.label));
1166 chipinfo.label[sizeof(chipinfo.label)-1] = '\0';
1167 chipinfo.lines = gdev->ngpio;
1168 if (copy_to_user(ip, &chipinfo, sizeof(chipinfo)))
1171 } else if (cmd == GPIO_GET_LINEINFO_IOCTL) {
1172 struct gpioline_info lineinfo;
1173 struct gpio_desc *desc;
1175 if (copy_from_user(&lineinfo, ip, sizeof(lineinfo)))
1178 desc = gpiochip_get_desc(chip, lineinfo.line_offset);
1180 return PTR_ERR(desc);
1183 strncpy(lineinfo.name, desc->name,
1184 sizeof(lineinfo.name));
1185 lineinfo.name[sizeof(lineinfo.name)-1] = '\0';
1187 lineinfo.name[0] = '\0';
1190 strncpy(lineinfo.consumer, desc->label,
1191 sizeof(lineinfo.consumer));
1192 lineinfo.consumer[sizeof(lineinfo.consumer)-1] = '\0';
1194 lineinfo.consumer[0] = '\0';
1198 * Userspace only need to know that the kernel is using
1199 * this GPIO so it can't use it.
1202 if (test_bit(FLAG_REQUESTED, &desc->flags) ||
1203 test_bit(FLAG_IS_HOGGED, &desc->flags) ||
1204 test_bit(FLAG_USED_AS_IRQ, &desc->flags) ||
1205 test_bit(FLAG_EXPORT, &desc->flags) ||
1206 test_bit(FLAG_SYSFS, &desc->flags) ||
1207 !pinctrl_gpio_can_use_line(chip->base + lineinfo.line_offset))
1208 lineinfo.flags |= GPIOLINE_FLAG_KERNEL;
1209 if (test_bit(FLAG_IS_OUT, &desc->flags))
1210 lineinfo.flags |= GPIOLINE_FLAG_IS_OUT;
1211 if (test_bit(FLAG_ACTIVE_LOW, &desc->flags))
1212 lineinfo.flags |= GPIOLINE_FLAG_ACTIVE_LOW;
1213 if (test_bit(FLAG_OPEN_DRAIN, &desc->flags))
1214 lineinfo.flags |= (GPIOLINE_FLAG_OPEN_DRAIN |
1215 GPIOLINE_FLAG_IS_OUT);
1216 if (test_bit(FLAG_OPEN_SOURCE, &desc->flags))
1217 lineinfo.flags |= (GPIOLINE_FLAG_OPEN_SOURCE |
1218 GPIOLINE_FLAG_IS_OUT);
1219 if (test_bit(FLAG_BIAS_DISABLE, &desc->flags))
1220 lineinfo.flags |= GPIOLINE_FLAG_BIAS_DISABLE;
1221 if (test_bit(FLAG_PULL_DOWN, &desc->flags))
1222 lineinfo.flags |= GPIOLINE_FLAG_BIAS_PULL_DOWN;
1223 if (test_bit(FLAG_PULL_UP, &desc->flags))
1224 lineinfo.flags |= GPIOLINE_FLAG_BIAS_PULL_UP;
1226 if (copy_to_user(ip, &lineinfo, sizeof(lineinfo)))
1229 } else if (cmd == GPIO_GET_LINEHANDLE_IOCTL) {
1230 return linehandle_create(gdev, ip);
1231 } else if (cmd == GPIO_GET_LINEEVENT_IOCTL) {
1232 return lineevent_create(gdev, ip);
1237 #ifdef CONFIG_COMPAT
1238 static long gpio_ioctl_compat(struct file *filp, unsigned int cmd,
1241 return gpio_ioctl(filp, cmd, (unsigned long)compat_ptr(arg));
1246 * gpio_chrdev_open() - open the chardev for ioctl operations
1247 * @inode: inode for this chardev
1248 * @filp: file struct for storing private data
1249 * Returns 0 on success
1251 static int gpio_chrdev_open(struct inode *inode, struct file *filp)
1253 struct gpio_device *gdev = container_of(inode->i_cdev,
1254 struct gpio_device, chrdev);
1256 /* Fail on open if the backing gpiochip is gone */
1259 get_device(&gdev->dev);
1260 filp->private_data = gdev;
1262 return nonseekable_open(inode, filp);
1266 * gpio_chrdev_release() - close chardev after ioctl operations
1267 * @inode: inode for this chardev
1268 * @filp: file struct for storing private data
1269 * Returns 0 on success
1271 static int gpio_chrdev_release(struct inode *inode, struct file *filp)
1273 struct gpio_device *gdev = container_of(inode->i_cdev,
1274 struct gpio_device, chrdev);
1276 put_device(&gdev->dev);
1281 static const struct file_operations gpio_fileops = {
1282 .release = gpio_chrdev_release,
1283 .open = gpio_chrdev_open,
1284 .owner = THIS_MODULE,
1285 .llseek = no_llseek,
1286 .unlocked_ioctl = gpio_ioctl,
1287 #ifdef CONFIG_COMPAT
1288 .compat_ioctl = gpio_ioctl_compat,
1292 static void gpiodevice_release(struct device *dev)
1294 struct gpio_device *gdev = dev_get_drvdata(dev);
1296 list_del(&gdev->list);
1297 ida_simple_remove(&gpio_ida, gdev->id);
1298 kfree_const(gdev->label);
1303 static int gpiochip_setup_dev(struct gpio_device *gdev)
1307 cdev_init(&gdev->chrdev, &gpio_fileops);
1308 gdev->chrdev.owner = THIS_MODULE;
1309 gdev->dev.devt = MKDEV(MAJOR(gpio_devt), gdev->id);
1311 ret = cdev_device_add(&gdev->chrdev, &gdev->dev);
1315 chip_dbg(gdev->chip, "added GPIO chardev (%d:%d)\n",
1316 MAJOR(gpio_devt), gdev->id);
1318 ret = gpiochip_sysfs_register(gdev);
1320 goto err_remove_device;
1322 /* From this point, the .release() function cleans up gpio_device */
1323 gdev->dev.release = gpiodevice_release;
1324 pr_debug("%s: registered GPIOs %d to %d on device: %s (%s)\n",
1325 __func__, gdev->base, gdev->base + gdev->ngpio - 1,
1326 dev_name(&gdev->dev), gdev->chip->label ? : "generic");
1331 cdev_device_del(&gdev->chrdev, &gdev->dev);
1335 static void gpiochip_machine_hog(struct gpio_chip *chip, struct gpiod_hog *hog)
1337 struct gpio_desc *desc;
1340 desc = gpiochip_get_desc(chip, hog->chip_hwnum);
1342 pr_err("%s: unable to get GPIO desc: %ld\n",
1343 __func__, PTR_ERR(desc));
1347 if (test_bit(FLAG_IS_HOGGED, &desc->flags))
1350 rv = gpiod_hog(desc, hog->line_name, hog->lflags, hog->dflags);
1352 pr_err("%s: unable to hog GPIO line (%s:%u): %d\n",
1353 __func__, chip->label, hog->chip_hwnum, rv);
1356 static void machine_gpiochip_add(struct gpio_chip *chip)
1358 struct gpiod_hog *hog;
1360 mutex_lock(&gpio_machine_hogs_mutex);
1362 list_for_each_entry(hog, &gpio_machine_hogs, list) {
1363 if (!strcmp(chip->label, hog->chip_label))
1364 gpiochip_machine_hog(chip, hog);
1367 mutex_unlock(&gpio_machine_hogs_mutex);
1370 static void gpiochip_setup_devs(void)
1372 struct gpio_device *gdev;
1375 list_for_each_entry(gdev, &gpio_devices, list) {
1376 ret = gpiochip_setup_dev(gdev);
1378 pr_err("%s: Failed to initialize gpio device (%d)\n",
1379 dev_name(&gdev->dev), ret);
1383 int gpiochip_add_data_with_key(struct gpio_chip *chip, void *data,
1384 struct lock_class_key *lock_key,
1385 struct lock_class_key *request_key)
1387 unsigned long flags;
1390 int base = chip->base;
1391 struct gpio_device *gdev;
1394 * First: allocate and populate the internal stat container, and
1395 * set up the struct device.
1397 gdev = kzalloc(sizeof(*gdev), GFP_KERNEL);
1400 gdev->dev.bus = &gpio_bus_type;
1402 chip->gpiodev = gdev;
1404 gdev->dev.parent = chip->parent;
1405 gdev->dev.of_node = chip->parent->of_node;
1408 #ifdef CONFIG_OF_GPIO
1409 /* If the gpiochip has an assigned OF node this takes precedence */
1411 gdev->dev.of_node = chip->of_node;
1413 chip->of_node = gdev->dev.of_node;
1416 gdev->id = ida_simple_get(&gpio_ida, 0, 0, GFP_KERNEL);
1421 dev_set_name(&gdev->dev, GPIOCHIP_NAME "%d", gdev->id);
1422 device_initialize(&gdev->dev);
1423 dev_set_drvdata(&gdev->dev, gdev);
1424 if (chip->parent && chip->parent->driver)
1425 gdev->owner = chip->parent->driver->owner;
1426 else if (chip->owner)
1427 /* TODO: remove chip->owner */
1428 gdev->owner = chip->owner;
1430 gdev->owner = THIS_MODULE;
1432 gdev->descs = kcalloc(chip->ngpio, sizeof(gdev->descs[0]), GFP_KERNEL);
1438 if (chip->ngpio == 0) {
1439 chip_err(chip, "tried to insert a GPIO chip with zero lines\n");
1441 goto err_free_descs;
1444 if (chip->ngpio > FASTPATH_NGPIO)
1445 chip_warn(chip, "line cnt %u is greater than fast path cnt %u\n",
1446 chip->ngpio, FASTPATH_NGPIO);
1448 gdev->label = kstrdup_const(chip->label ?: "unknown", GFP_KERNEL);
1451 goto err_free_descs;
1454 gdev->ngpio = chip->ngpio;
1457 spin_lock_irqsave(&gpio_lock, flags);
1460 * TODO: this allocates a Linux GPIO number base in the global
1461 * GPIO numberspace for this chip. In the long run we want to
1462 * get *rid* of this numberspace and use only descriptors, but
1463 * it may be a pipe dream. It will not happen before we get rid
1464 * of the sysfs interface anyways.
1467 base = gpiochip_find_base(chip->ngpio);
1470 spin_unlock_irqrestore(&gpio_lock, flags);
1471 goto err_free_label;
1474 * TODO: it should not be necessary to reflect the assigned
1475 * base outside of the GPIO subsystem. Go over drivers and
1476 * see if anyone makes use of this, else drop this and assign
1483 ret = gpiodev_add_to_list(gdev);
1485 spin_unlock_irqrestore(&gpio_lock, flags);
1486 goto err_free_label;
1489 for (i = 0; i < chip->ngpio; i++)
1490 gdev->descs[i].gdev = gdev;
1492 spin_unlock_irqrestore(&gpio_lock, flags);
1494 #ifdef CONFIG_PINCTRL
1495 INIT_LIST_HEAD(&gdev->pin_ranges);
1498 ret = gpiochip_set_desc_names(chip);
1500 goto err_remove_from_list;
1502 ret = gpiochip_alloc_valid_mask(chip);
1504 goto err_remove_from_list;
1506 ret = of_gpiochip_add(chip);
1508 goto err_free_gpiochip_mask;
1510 ret = gpiochip_init_valid_mask(chip);
1512 goto err_remove_of_chip;
1514 for (i = 0; i < chip->ngpio; i++) {
1515 struct gpio_desc *desc = &gdev->descs[i];
1517 if (chip->get_direction && gpiochip_line_is_valid(chip, i)) {
1518 assign_bit(FLAG_IS_OUT,
1519 &desc->flags, !chip->get_direction(chip, i));
1521 assign_bit(FLAG_IS_OUT,
1522 &desc->flags, !chip->direction_input);
1526 ret = gpiochip_add_pin_ranges(chip);
1528 goto err_remove_of_chip;
1530 acpi_gpiochip_add(chip);
1532 machine_gpiochip_add(chip);
1534 ret = gpiochip_irqchip_init_valid_mask(chip);
1536 goto err_remove_acpi_chip;
1538 ret = gpiochip_irqchip_init_hw(chip);
1540 goto err_remove_acpi_chip;
1542 ret = gpiochip_add_irqchip(chip, lock_key, request_key);
1544 goto err_remove_irqchip_mask;
1547 * By first adding the chardev, and then adding the device,
1548 * we get a device node entry in sysfs under
1549 * /sys/bus/gpio/devices/gpiochipN/dev that can be used for
1550 * coldplug of device nodes and other udev business.
1551 * We can do this only if gpiolib has been initialized.
1552 * Otherwise, defer until later.
1554 if (gpiolib_initialized) {
1555 ret = gpiochip_setup_dev(gdev);
1557 goto err_remove_irqchip;
1562 gpiochip_irqchip_remove(chip);
1563 err_remove_irqchip_mask:
1564 gpiochip_irqchip_free_valid_mask(chip);
1565 err_remove_acpi_chip:
1566 acpi_gpiochip_remove(chip);
1568 gpiochip_free_hogs(chip);
1569 of_gpiochip_remove(chip);
1570 err_free_gpiochip_mask:
1571 gpiochip_remove_pin_ranges(chip);
1572 gpiochip_free_valid_mask(chip);
1573 err_remove_from_list:
1574 spin_lock_irqsave(&gpio_lock, flags);
1575 list_del(&gdev->list);
1576 spin_unlock_irqrestore(&gpio_lock, flags);
1578 kfree_const(gdev->label);
1582 ida_simple_remove(&gpio_ida, gdev->id);
1584 /* failures here can mean systems won't boot... */
1585 pr_err("%s: GPIOs %d..%d (%s) failed to register, %d\n", __func__,
1586 gdev->base, gdev->base + gdev->ngpio - 1,
1587 chip->label ? : "generic", ret);
1591 EXPORT_SYMBOL_GPL(gpiochip_add_data_with_key);
1594 * gpiochip_get_data() - get per-subdriver data for the chip
1598 * The per-subdriver data for the chip.
1600 void *gpiochip_get_data(struct gpio_chip *chip)
1602 return chip->gpiodev->data;
1604 EXPORT_SYMBOL_GPL(gpiochip_get_data);
1607 * gpiochip_remove() - unregister a gpio_chip
1608 * @chip: the chip to unregister
1610 * A gpio_chip with any GPIOs still requested may not be removed.
1612 void gpiochip_remove(struct gpio_chip *chip)
1614 struct gpio_device *gdev = chip->gpiodev;
1615 struct gpio_desc *desc;
1616 unsigned long flags;
1618 bool requested = false;
1620 /* FIXME: should the legacy sysfs handling be moved to gpio_device? */
1621 gpiochip_sysfs_unregister(gdev);
1622 gpiochip_free_hogs(chip);
1623 /* Numb the device, cancelling all outstanding operations */
1625 gpiochip_irqchip_remove(chip);
1626 acpi_gpiochip_remove(chip);
1627 of_gpiochip_remove(chip);
1628 gpiochip_remove_pin_ranges(chip);
1629 gpiochip_free_valid_mask(chip);
1631 * We accept no more calls into the driver from this point, so
1632 * NULL the driver data pointer
1636 spin_lock_irqsave(&gpio_lock, flags);
1637 for (i = 0; i < gdev->ngpio; i++) {
1638 desc = &gdev->descs[i];
1639 if (test_bit(FLAG_REQUESTED, &desc->flags))
1642 spin_unlock_irqrestore(&gpio_lock, flags);
1645 dev_crit(&gdev->dev,
1646 "REMOVING GPIOCHIP WITH GPIOS STILL REQUESTED\n");
1649 * The gpiochip side puts its use of the device to rest here:
1650 * if there are no userspace clients, the chardev and device will
1651 * be removed, else it will be dangling until the last user is
1654 cdev_device_del(&gdev->chrdev, &gdev->dev);
1655 put_device(&gdev->dev);
1657 EXPORT_SYMBOL_GPL(gpiochip_remove);
1659 static void devm_gpio_chip_release(struct device *dev, void *res)
1661 struct gpio_chip *chip = *(struct gpio_chip **)res;
1663 gpiochip_remove(chip);
1667 * devm_gpiochip_add_data() - Resource managed gpiochip_add_data()
1668 * @dev: pointer to the device that gpio_chip belongs to.
1669 * @chip: the chip to register, with chip->base initialized
1670 * @data: driver-private data associated with this chip
1672 * Context: potentially before irqs will work
1674 * The gpio chip automatically be released when the device is unbound.
1677 * A negative errno if the chip can't be registered, such as because the
1678 * chip->base is invalid or already associated with a different chip.
1679 * Otherwise it returns zero as a success code.
1681 int devm_gpiochip_add_data(struct device *dev, struct gpio_chip *chip,
1684 struct gpio_chip **ptr;
1687 ptr = devres_alloc(devm_gpio_chip_release, sizeof(*ptr),
1692 ret = gpiochip_add_data(chip, data);
1699 devres_add(dev, ptr);
1703 EXPORT_SYMBOL_GPL(devm_gpiochip_add_data);
1706 * gpiochip_find() - iterator for locating a specific gpio_chip
1707 * @data: data to pass to match function
1708 * @match: Callback function to check gpio_chip
1710 * Similar to bus_find_device. It returns a reference to a gpio_chip as
1711 * determined by a user supplied @match callback. The callback should return
1712 * 0 if the device doesn't match and non-zero if it does. If the callback is
1713 * non-zero, this function will return to the caller and not iterate over any
1716 struct gpio_chip *gpiochip_find(void *data,
1717 int (*match)(struct gpio_chip *chip,
1720 struct gpio_device *gdev;
1721 struct gpio_chip *chip = NULL;
1722 unsigned long flags;
1724 spin_lock_irqsave(&gpio_lock, flags);
1725 list_for_each_entry(gdev, &gpio_devices, list)
1726 if (gdev->chip && match(gdev->chip, data)) {
1731 spin_unlock_irqrestore(&gpio_lock, flags);
1735 EXPORT_SYMBOL_GPL(gpiochip_find);
1737 static int gpiochip_match_name(struct gpio_chip *chip, void *data)
1739 const char *name = data;
1741 return !strcmp(chip->label, name);
1744 static struct gpio_chip *find_chip_by_name(const char *name)
1746 return gpiochip_find((void *)name, gpiochip_match_name);
1749 #ifdef CONFIG_GPIOLIB_IRQCHIP
1752 * The following is irqchip helper code for gpiochips.
1755 static int gpiochip_irqchip_init_hw(struct gpio_chip *gc)
1757 struct gpio_irq_chip *girq = &gc->irq;
1762 return girq->init_hw(gc);
1765 static int gpiochip_irqchip_init_valid_mask(struct gpio_chip *gc)
1767 struct gpio_irq_chip *girq = &gc->irq;
1769 if (!girq->init_valid_mask)
1772 girq->valid_mask = gpiochip_allocate_mask(gc);
1773 if (!girq->valid_mask)
1776 girq->init_valid_mask(gc, girq->valid_mask, gc->ngpio);
1781 static void gpiochip_irqchip_free_valid_mask(struct gpio_chip *gpiochip)
1783 bitmap_free(gpiochip->irq.valid_mask);
1784 gpiochip->irq.valid_mask = NULL;
1787 bool gpiochip_irqchip_irq_valid(const struct gpio_chip *gpiochip,
1788 unsigned int offset)
1790 if (!gpiochip_line_is_valid(gpiochip, offset))
1792 /* No mask means all valid */
1793 if (likely(!gpiochip->irq.valid_mask))
1795 return test_bit(offset, gpiochip->irq.valid_mask);
1797 EXPORT_SYMBOL_GPL(gpiochip_irqchip_irq_valid);
1800 * gpiochip_set_cascaded_irqchip() - connects a cascaded irqchip to a gpiochip
1801 * @gc: the gpiochip to set the irqchip chain to
1802 * @parent_irq: the irq number corresponding to the parent IRQ for this
1804 * @parent_handler: the parent interrupt handler for the accumulated IRQ
1805 * coming out of the gpiochip. If the interrupt is nested rather than
1806 * cascaded, pass NULL in this handler argument
1808 static void gpiochip_set_cascaded_irqchip(struct gpio_chip *gc,
1809 unsigned int parent_irq,
1810 irq_flow_handler_t parent_handler)
1812 struct gpio_irq_chip *girq = &gc->irq;
1813 struct device *dev = &gc->gpiodev->dev;
1815 if (!girq->domain) {
1816 chip_err(gc, "called %s before setting up irqchip\n",
1821 if (parent_handler) {
1822 if (gc->can_sleep) {
1824 "you cannot have chained interrupts on a chip that may sleep\n");
1827 girq->parents = devm_kcalloc(dev, 1,
1828 sizeof(*girq->parents),
1830 if (!girq->parents) {
1831 chip_err(gc, "out of memory allocating parent IRQ\n");
1834 girq->parents[0] = parent_irq;
1835 girq->num_parents = 1;
1837 * The parent irqchip is already using the chip_data for this
1838 * irqchip, so our callbacks simply use the handler_data.
1840 irq_set_chained_handler_and_data(parent_irq, parent_handler,
1846 * gpiochip_set_nested_irqchip() - connects a nested irqchip to a gpiochip
1847 * @gpiochip: the gpiochip to set the irqchip nested handler to
1848 * @irqchip: the irqchip to nest to the gpiochip
1849 * @parent_irq: the irq number corresponding to the parent IRQ for this
1852 void gpiochip_set_nested_irqchip(struct gpio_chip *gpiochip,
1853 struct irq_chip *irqchip,
1854 unsigned int parent_irq)
1856 gpiochip_set_cascaded_irqchip(gpiochip, parent_irq, NULL);
1858 EXPORT_SYMBOL_GPL(gpiochip_set_nested_irqchip);
1860 #ifdef CONFIG_IRQ_DOMAIN_HIERARCHY
1863 * gpiochip_set_hierarchical_irqchip() - connects a hierarchical irqchip
1865 * @gc: the gpiochip to set the irqchip hierarchical handler to
1866 * @irqchip: the irqchip to handle this level of the hierarchy, the interrupt
1867 * will then percolate up to the parent
1869 static void gpiochip_set_hierarchical_irqchip(struct gpio_chip *gc,
1870 struct irq_chip *irqchip)
1872 /* DT will deal with mapping each IRQ as we go along */
1873 if (is_of_node(gc->irq.fwnode))
1877 * This is for legacy and boardfile "irqchip" fwnodes: allocate
1878 * irqs upfront instead of dynamically since we don't have the
1879 * dynamic type of allocation that hardware description languages
1880 * provide. Once all GPIO drivers using board files are gone from
1881 * the kernel we can delete this code, but for a transitional period
1882 * it is necessary to keep this around.
1884 if (is_fwnode_irqchip(gc->irq.fwnode)) {
1888 for (i = 0; i < gc->ngpio; i++) {
1889 struct irq_fwspec fwspec;
1890 unsigned int parent_hwirq;
1891 unsigned int parent_type;
1892 struct gpio_irq_chip *girq = &gc->irq;
1895 * We call the child to parent translation function
1896 * only to check if the child IRQ is valid or not.
1897 * Just pick the rising edge type here as that is what
1898 * we likely need to support.
1900 ret = girq->child_to_parent_hwirq(gc, i,
1901 IRQ_TYPE_EDGE_RISING,
1905 chip_err(gc, "skip set-up on hwirq %d\n",
1910 fwspec.fwnode = gc->irq.fwnode;
1911 /* This is the hwirq for the GPIO line side of things */
1912 fwspec.param[0] = girq->child_offset_to_irq(gc, i);
1913 /* Just pick something */
1914 fwspec.param[1] = IRQ_TYPE_EDGE_RISING;
1915 fwspec.param_count = 2;
1916 ret = __irq_domain_alloc_irqs(gc->irq.domain,
1917 /* just pick something */
1926 "can not allocate irq for GPIO line %d parent hwirq %d in hierarchy domain: %d\n",
1933 chip_err(gc, "%s unknown fwnode type proceed anyway\n", __func__);
1938 static int gpiochip_hierarchy_irq_domain_translate(struct irq_domain *d,
1939 struct irq_fwspec *fwspec,
1940 unsigned long *hwirq,
1943 /* We support standard DT translation */
1944 if (is_of_node(fwspec->fwnode) && fwspec->param_count == 2) {
1945 return irq_domain_translate_twocell(d, fwspec, hwirq, type);
1948 /* This is for board files and others not using DT */
1949 if (is_fwnode_irqchip(fwspec->fwnode)) {
1952 ret = irq_domain_translate_twocell(d, fwspec, hwirq, type);
1955 WARN_ON(*type == IRQ_TYPE_NONE);
1961 static int gpiochip_hierarchy_irq_domain_alloc(struct irq_domain *d,
1963 unsigned int nr_irqs,
1966 struct gpio_chip *gc = d->host_data;
1967 irq_hw_number_t hwirq;
1968 unsigned int type = IRQ_TYPE_NONE;
1969 struct irq_fwspec *fwspec = data;
1971 unsigned int parent_hwirq;
1972 unsigned int parent_type;
1973 struct gpio_irq_chip *girq = &gc->irq;
1977 * The nr_irqs parameter is always one except for PCI multi-MSI
1978 * so this should not happen.
1980 WARN_ON(nr_irqs != 1);
1982 ret = gc->irq.child_irq_domain_ops.translate(d, fwspec, &hwirq, &type);
1986 chip_dbg(gc, "allocate IRQ %d, hwirq %lu\n", irq, hwirq);
1988 ret = girq->child_to_parent_hwirq(gc, hwirq, type,
1989 &parent_hwirq, &parent_type);
1991 chip_err(gc, "can't look up hwirq %lu\n", hwirq);
1994 chip_dbg(gc, "found parent hwirq %u\n", parent_hwirq);
1997 * We set handle_bad_irq because the .set_type() should
1998 * always be invoked and set the right type of handler.
2000 irq_domain_set_info(d,
2009 /* This parent only handles asserted level IRQs */
2010 parent_arg = girq->populate_parent_alloc_arg(gc, parent_hwirq, parent_type);
2014 chip_dbg(gc, "alloc_irqs_parent for %d parent hwirq %d\n",
2016 irq_set_lockdep_class(irq, gc->irq.lock_key, gc->irq.request_key);
2017 ret = irq_domain_alloc_irqs_parent(d, irq, 1, parent_arg);
2019 * If the parent irqdomain is msi, the interrupts have already
2020 * been allocated, so the EEXIST is good.
2022 if (irq_domain_is_msi(d->parent) && (ret == -EEXIST))
2026 "failed to allocate parent hwirq %d for hwirq %lu\n",
2027 parent_hwirq, hwirq);
2033 static unsigned int gpiochip_child_offset_to_irq_noop(struct gpio_chip *chip,
2034 unsigned int offset)
2039 static void gpiochip_hierarchy_setup_domain_ops(struct irq_domain_ops *ops)
2041 ops->activate = gpiochip_irq_domain_activate;
2042 ops->deactivate = gpiochip_irq_domain_deactivate;
2043 ops->alloc = gpiochip_hierarchy_irq_domain_alloc;
2044 ops->free = irq_domain_free_irqs_common;
2047 * We only allow overriding the translate() function for
2048 * hierarchical chips, and this should only be done if the user
2049 * really need something other than 1:1 translation.
2051 if (!ops->translate)
2052 ops->translate = gpiochip_hierarchy_irq_domain_translate;
2055 static int gpiochip_hierarchy_add_domain(struct gpio_chip *gc)
2057 if (!gc->irq.child_to_parent_hwirq ||
2059 chip_err(gc, "missing irqdomain vital data\n");
2063 if (!gc->irq.child_offset_to_irq)
2064 gc->irq.child_offset_to_irq = gpiochip_child_offset_to_irq_noop;
2066 if (!gc->irq.populate_parent_alloc_arg)
2067 gc->irq.populate_parent_alloc_arg =
2068 gpiochip_populate_parent_fwspec_twocell;
2070 gpiochip_hierarchy_setup_domain_ops(&gc->irq.child_irq_domain_ops);
2072 gc->irq.domain = irq_domain_create_hierarchy(
2073 gc->irq.parent_domain,
2077 &gc->irq.child_irq_domain_ops,
2080 if (!gc->irq.domain)
2083 gpiochip_set_hierarchical_irqchip(gc, gc->irq.chip);
2088 static bool gpiochip_hierarchy_is_hierarchical(struct gpio_chip *gc)
2090 return !!gc->irq.parent_domain;
2093 void *gpiochip_populate_parent_fwspec_twocell(struct gpio_chip *chip,
2094 unsigned int parent_hwirq,
2095 unsigned int parent_type)
2097 struct irq_fwspec *fwspec;
2099 fwspec = kmalloc(sizeof(*fwspec), GFP_KERNEL);
2103 fwspec->fwnode = chip->irq.parent_domain->fwnode;
2104 fwspec->param_count = 2;
2105 fwspec->param[0] = parent_hwirq;
2106 fwspec->param[1] = parent_type;
2110 EXPORT_SYMBOL_GPL(gpiochip_populate_parent_fwspec_twocell);
2112 void *gpiochip_populate_parent_fwspec_fourcell(struct gpio_chip *chip,
2113 unsigned int parent_hwirq,
2114 unsigned int parent_type)
2116 struct irq_fwspec *fwspec;
2118 fwspec = kmalloc(sizeof(*fwspec), GFP_KERNEL);
2122 fwspec->fwnode = chip->irq.parent_domain->fwnode;
2123 fwspec->param_count = 4;
2124 fwspec->param[0] = 0;
2125 fwspec->param[1] = parent_hwirq;
2126 fwspec->param[2] = 0;
2127 fwspec->param[3] = parent_type;
2131 EXPORT_SYMBOL_GPL(gpiochip_populate_parent_fwspec_fourcell);
2135 static int gpiochip_hierarchy_add_domain(struct gpio_chip *gc)
2140 static bool gpiochip_hierarchy_is_hierarchical(struct gpio_chip *gc)
2145 #endif /* CONFIG_IRQ_DOMAIN_HIERARCHY */
2148 * gpiochip_irq_map() - maps an IRQ into a GPIO irqchip
2149 * @d: the irqdomain used by this irqchip
2150 * @irq: the global irq number used by this GPIO irqchip irq
2151 * @hwirq: the local IRQ/GPIO line offset on this gpiochip
2153 * This function will set up the mapping for a certain IRQ line on a
2154 * gpiochip by assigning the gpiochip as chip data, and using the irqchip
2155 * stored inside the gpiochip.
2157 int gpiochip_irq_map(struct irq_domain *d, unsigned int irq,
2158 irq_hw_number_t hwirq)
2160 struct gpio_chip *chip = d->host_data;
2163 if (!gpiochip_irqchip_irq_valid(chip, hwirq))
2166 irq_set_chip_data(irq, chip);
2168 * This lock class tells lockdep that GPIO irqs are in a different
2169 * category than their parents, so it won't report false recursion.
2171 irq_set_lockdep_class(irq, chip->irq.lock_key, chip->irq.request_key);
2172 irq_set_chip_and_handler(irq, chip->irq.chip, chip->irq.handler);
2173 /* Chips that use nested thread handlers have them marked */
2174 if (chip->irq.threaded)
2175 irq_set_nested_thread(irq, 1);
2176 irq_set_noprobe(irq);
2178 if (chip->irq.num_parents == 1)
2179 ret = irq_set_parent(irq, chip->irq.parents[0]);
2180 else if (chip->irq.map)
2181 ret = irq_set_parent(irq, chip->irq.map[hwirq]);
2187 * No set-up of the hardware will happen if IRQ_TYPE_NONE
2188 * is passed as default type.
2190 if (chip->irq.default_type != IRQ_TYPE_NONE)
2191 irq_set_irq_type(irq, chip->irq.default_type);
2195 EXPORT_SYMBOL_GPL(gpiochip_irq_map);
2197 void gpiochip_irq_unmap(struct irq_domain *d, unsigned int irq)
2199 struct gpio_chip *chip = d->host_data;
2201 if (chip->irq.threaded)
2202 irq_set_nested_thread(irq, 0);
2203 irq_set_chip_and_handler(irq, NULL, NULL);
2204 irq_set_chip_data(irq, NULL);
2206 EXPORT_SYMBOL_GPL(gpiochip_irq_unmap);
2208 static const struct irq_domain_ops gpiochip_domain_ops = {
2209 .map = gpiochip_irq_map,
2210 .unmap = gpiochip_irq_unmap,
2211 /* Virtually all GPIO irqchips are twocell:ed */
2212 .xlate = irq_domain_xlate_twocell,
2216 * TODO: move these activate/deactivate in under the hierarchicial
2217 * irqchip implementation as static once SPMI and SSBI (all external
2218 * users) are phased over.
2221 * gpiochip_irq_domain_activate() - Lock a GPIO to be used as an IRQ
2222 * @domain: The IRQ domain used by this IRQ chip
2223 * @data: Outermost irq_data associated with the IRQ
2224 * @reserve: If set, only reserve an interrupt vector instead of assigning one
2226 * This function is a wrapper that calls gpiochip_lock_as_irq() and is to be
2227 * used as the activate function for the &struct irq_domain_ops. The host_data
2228 * for the IRQ domain must be the &struct gpio_chip.
2230 int gpiochip_irq_domain_activate(struct irq_domain *domain,
2231 struct irq_data *data, bool reserve)
2233 struct gpio_chip *chip = domain->host_data;
2235 return gpiochip_lock_as_irq(chip, data->hwirq);
2237 EXPORT_SYMBOL_GPL(gpiochip_irq_domain_activate);
2240 * gpiochip_irq_domain_deactivate() - Unlock a GPIO used as an IRQ
2241 * @domain: The IRQ domain used by this IRQ chip
2242 * @data: Outermost irq_data associated with the IRQ
2244 * This function is a wrapper that will call gpiochip_unlock_as_irq() and is to
2245 * be used as the deactivate function for the &struct irq_domain_ops. The
2246 * host_data for the IRQ domain must be the &struct gpio_chip.
2248 void gpiochip_irq_domain_deactivate(struct irq_domain *domain,
2249 struct irq_data *data)
2251 struct gpio_chip *chip = domain->host_data;
2253 return gpiochip_unlock_as_irq(chip, data->hwirq);
2255 EXPORT_SYMBOL_GPL(gpiochip_irq_domain_deactivate);
2257 static int gpiochip_to_irq(struct gpio_chip *chip, unsigned offset)
2259 struct irq_domain *domain = chip->irq.domain;
2261 if (!gpiochip_irqchip_irq_valid(chip, offset))
2264 #ifdef CONFIG_IRQ_DOMAIN_HIERARCHY
2265 if (irq_domain_is_hierarchy(domain)) {
2266 struct irq_fwspec spec;
2268 spec.fwnode = domain->fwnode;
2269 spec.param_count = 2;
2270 spec.param[0] = chip->irq.child_offset_to_irq(chip, offset);
2271 spec.param[1] = IRQ_TYPE_NONE;
2273 return irq_create_fwspec_mapping(&spec);
2277 return irq_create_mapping(domain, offset);
2280 static int gpiochip_irq_reqres(struct irq_data *d)
2282 struct gpio_chip *chip = irq_data_get_irq_chip_data(d);
2284 return gpiochip_reqres_irq(chip, d->hwirq);
2287 static void gpiochip_irq_relres(struct irq_data *d)
2289 struct gpio_chip *chip = irq_data_get_irq_chip_data(d);
2291 gpiochip_relres_irq(chip, d->hwirq);
2294 static void gpiochip_irq_enable(struct irq_data *d)
2296 struct gpio_chip *chip = irq_data_get_irq_chip_data(d);
2298 gpiochip_enable_irq(chip, d->hwirq);
2299 if (chip->irq.irq_enable)
2300 chip->irq.irq_enable(d);
2302 chip->irq.chip->irq_unmask(d);
2305 static void gpiochip_irq_disable(struct irq_data *d)
2307 struct gpio_chip *chip = irq_data_get_irq_chip_data(d);
2309 if (chip->irq.irq_disable)
2310 chip->irq.irq_disable(d);
2312 chip->irq.chip->irq_mask(d);
2313 gpiochip_disable_irq(chip, d->hwirq);
2316 static void gpiochip_set_irq_hooks(struct gpio_chip *gpiochip)
2318 struct irq_chip *irqchip = gpiochip->irq.chip;
2320 if (!irqchip->irq_request_resources &&
2321 !irqchip->irq_release_resources) {
2322 irqchip->irq_request_resources = gpiochip_irq_reqres;
2323 irqchip->irq_release_resources = gpiochip_irq_relres;
2325 if (WARN_ON(gpiochip->irq.irq_enable))
2327 /* Check if the irqchip already has this hook... */
2328 if (irqchip->irq_enable == gpiochip_irq_enable) {
2330 * ...and if so, give a gentle warning that this is bad
2334 "detected irqchip that is shared with multiple gpiochips: please fix the driver.\n");
2337 gpiochip->irq.irq_enable = irqchip->irq_enable;
2338 gpiochip->irq.irq_disable = irqchip->irq_disable;
2339 irqchip->irq_enable = gpiochip_irq_enable;
2340 irqchip->irq_disable = gpiochip_irq_disable;
2344 * gpiochip_add_irqchip() - adds an IRQ chip to a GPIO chip
2345 * @gpiochip: the GPIO chip to add the IRQ chip to
2346 * @lock_key: lockdep class for IRQ lock
2347 * @request_key: lockdep class for IRQ request
2349 static int gpiochip_add_irqchip(struct gpio_chip *gpiochip,
2350 struct lock_class_key *lock_key,
2351 struct lock_class_key *request_key)
2353 struct irq_chip *irqchip = gpiochip->irq.chip;
2354 const struct irq_domain_ops *ops = NULL;
2355 struct device_node *np;
2362 if (gpiochip->irq.parent_handler && gpiochip->can_sleep) {
2363 chip_err(gpiochip, "you cannot have chained interrupts on a chip that may sleep\n");
2367 np = gpiochip->gpiodev->dev.of_node;
2368 type = gpiochip->irq.default_type;
2371 * Specifying a default trigger is a terrible idea if DT or ACPI is
2372 * used to configure the interrupts, as you may end up with
2373 * conflicting triggers. Tell the user, and reset to NONE.
2375 if (WARN(np && type != IRQ_TYPE_NONE,
2376 "%s: Ignoring %u default trigger\n", np->full_name, type))
2377 type = IRQ_TYPE_NONE;
2379 if (has_acpi_companion(gpiochip->parent) && type != IRQ_TYPE_NONE) {
2380 acpi_handle_warn(ACPI_HANDLE(gpiochip->parent),
2381 "Ignoring %u default trigger\n", type);
2382 type = IRQ_TYPE_NONE;
2385 gpiochip->to_irq = gpiochip_to_irq;
2386 gpiochip->irq.default_type = type;
2387 gpiochip->irq.lock_key = lock_key;
2388 gpiochip->irq.request_key = request_key;
2390 /* If a parent irqdomain is provided, let's build a hierarchy */
2391 if (gpiochip_hierarchy_is_hierarchical(gpiochip)) {
2392 int ret = gpiochip_hierarchy_add_domain(gpiochip);
2396 /* Some drivers provide custom irqdomain ops */
2397 if (gpiochip->irq.domain_ops)
2398 ops = gpiochip->irq.domain_ops;
2401 ops = &gpiochip_domain_ops;
2402 gpiochip->irq.domain = irq_domain_add_simple(np,
2404 gpiochip->irq.first,
2406 if (!gpiochip->irq.domain)
2410 if (gpiochip->irq.parent_handler) {
2411 void *data = gpiochip->irq.parent_handler_data ?: gpiochip;
2413 for (i = 0; i < gpiochip->irq.num_parents; i++) {
2415 * The parent IRQ chip is already using the chip_data
2416 * for this IRQ chip, so our callbacks simply use the
2419 irq_set_chained_handler_and_data(gpiochip->irq.parents[i],
2420 gpiochip->irq.parent_handler,
2425 gpiochip_set_irq_hooks(gpiochip);
2427 acpi_gpiochip_request_interrupts(gpiochip);
2433 * gpiochip_irqchip_remove() - removes an irqchip added to a gpiochip
2434 * @gpiochip: the gpiochip to remove the irqchip from
2436 * This is called only from gpiochip_remove()
2438 static void gpiochip_irqchip_remove(struct gpio_chip *gpiochip)
2440 struct irq_chip *irqchip = gpiochip->irq.chip;
2441 unsigned int offset;
2443 acpi_gpiochip_free_interrupts(gpiochip);
2445 if (irqchip && gpiochip->irq.parent_handler) {
2446 struct gpio_irq_chip *irq = &gpiochip->irq;
2449 for (i = 0; i < irq->num_parents; i++)
2450 irq_set_chained_handler_and_data(irq->parents[i],
2454 /* Remove all IRQ mappings and delete the domain */
2455 if (gpiochip->irq.domain) {
2458 for (offset = 0; offset < gpiochip->ngpio; offset++) {
2459 if (!gpiochip_irqchip_irq_valid(gpiochip, offset))
2462 irq = irq_find_mapping(gpiochip->irq.domain, offset);
2463 irq_dispose_mapping(irq);
2466 irq_domain_remove(gpiochip->irq.domain);
2470 if (irqchip->irq_request_resources == gpiochip_irq_reqres) {
2471 irqchip->irq_request_resources = NULL;
2472 irqchip->irq_release_resources = NULL;
2474 if (irqchip->irq_enable == gpiochip_irq_enable) {
2475 irqchip->irq_enable = gpiochip->irq.irq_enable;
2476 irqchip->irq_disable = gpiochip->irq.irq_disable;
2479 gpiochip->irq.irq_enable = NULL;
2480 gpiochip->irq.irq_disable = NULL;
2481 gpiochip->irq.chip = NULL;
2483 gpiochip_irqchip_free_valid_mask(gpiochip);
2487 * gpiochip_irqchip_add_key() - adds an irqchip to a gpiochip
2488 * @gpiochip: the gpiochip to add the irqchip to
2489 * @irqchip: the irqchip to add to the gpiochip
2490 * @first_irq: if not dynamically assigned, the base (first) IRQ to
2491 * allocate gpiochip irqs from
2492 * @handler: the irq handler to use (often a predefined irq core function)
2493 * @type: the default type for IRQs on this irqchip, pass IRQ_TYPE_NONE
2494 * to have the core avoid setting up any default type in the hardware.
2495 * @threaded: whether this irqchip uses a nested thread handler
2496 * @lock_key: lockdep class for IRQ lock
2497 * @request_key: lockdep class for IRQ request
2499 * This function closely associates a certain irqchip with a certain
2500 * gpiochip, providing an irq domain to translate the local IRQs to
2501 * global irqs in the gpiolib core, and making sure that the gpiochip
2502 * is passed as chip data to all related functions. Driver callbacks
2503 * need to use gpiochip_get_data() to get their local state containers back
2504 * from the gpiochip passed as chip data. An irqdomain will be stored
2505 * in the gpiochip that shall be used by the driver to handle IRQ number
2506 * translation. The gpiochip will need to be initialized and registered
2507 * before calling this function.
2509 * This function will handle two cell:ed simple IRQs and assumes all
2510 * the pins on the gpiochip can generate a unique IRQ. Everything else
2511 * need to be open coded.
2513 int gpiochip_irqchip_add_key(struct gpio_chip *gpiochip,
2514 struct irq_chip *irqchip,
2515 unsigned int first_irq,
2516 irq_flow_handler_t handler,
2519 struct lock_class_key *lock_key,
2520 struct lock_class_key *request_key)
2522 struct device_node *of_node;
2524 if (!gpiochip || !irqchip)
2527 if (!gpiochip->parent) {
2528 pr_err("missing gpiochip .dev parent pointer\n");
2531 gpiochip->irq.threaded = threaded;
2532 of_node = gpiochip->parent->of_node;
2533 #ifdef CONFIG_OF_GPIO
2535 * If the gpiochip has an assigned OF node this takes precedence
2536 * FIXME: get rid of this and use gpiochip->parent->of_node
2539 if (gpiochip->of_node)
2540 of_node = gpiochip->of_node;
2543 * Specifying a default trigger is a terrible idea if DT or ACPI is
2544 * used to configure the interrupts, as you may end-up with
2545 * conflicting triggers. Tell the user, and reset to NONE.
2547 if (WARN(of_node && type != IRQ_TYPE_NONE,
2548 "%pOF: Ignoring %d default trigger\n", of_node, type))
2549 type = IRQ_TYPE_NONE;
2550 if (has_acpi_companion(gpiochip->parent) && type != IRQ_TYPE_NONE) {
2551 acpi_handle_warn(ACPI_HANDLE(gpiochip->parent),
2552 "Ignoring %d default trigger\n", type);
2553 type = IRQ_TYPE_NONE;
2556 gpiochip->irq.chip = irqchip;
2557 gpiochip->irq.handler = handler;
2558 gpiochip->irq.default_type = type;
2559 gpiochip->to_irq = gpiochip_to_irq;
2560 gpiochip->irq.lock_key = lock_key;
2561 gpiochip->irq.request_key = request_key;
2562 gpiochip->irq.domain = irq_domain_add_simple(of_node,
2563 gpiochip->ngpio, first_irq,
2564 &gpiochip_domain_ops, gpiochip);
2565 if (!gpiochip->irq.domain) {
2566 gpiochip->irq.chip = NULL;
2570 gpiochip_set_irq_hooks(gpiochip);
2572 acpi_gpiochip_request_interrupts(gpiochip);
2576 EXPORT_SYMBOL_GPL(gpiochip_irqchip_add_key);
2578 #else /* CONFIG_GPIOLIB_IRQCHIP */
2580 static inline int gpiochip_add_irqchip(struct gpio_chip *gpiochip,
2581 struct lock_class_key *lock_key,
2582 struct lock_class_key *request_key)
2586 static void gpiochip_irqchip_remove(struct gpio_chip *gpiochip) {}
2588 static inline int gpiochip_irqchip_init_hw(struct gpio_chip *gpiochip)
2593 static inline int gpiochip_irqchip_init_valid_mask(struct gpio_chip *gpiochip)
2597 static inline void gpiochip_irqchip_free_valid_mask(struct gpio_chip *gpiochip)
2600 #endif /* CONFIG_GPIOLIB_IRQCHIP */
2603 * gpiochip_generic_request() - request the gpio function for a pin
2604 * @chip: the gpiochip owning the GPIO
2605 * @offset: the offset of the GPIO to request for GPIO function
2607 int gpiochip_generic_request(struct gpio_chip *chip, unsigned offset)
2609 return pinctrl_gpio_request(chip->gpiodev->base + offset);
2611 EXPORT_SYMBOL_GPL(gpiochip_generic_request);
2614 * gpiochip_generic_free() - free the gpio function from a pin
2615 * @chip: the gpiochip to request the gpio function for
2616 * @offset: the offset of the GPIO to free from GPIO function
2618 void gpiochip_generic_free(struct gpio_chip *chip, unsigned offset)
2620 pinctrl_gpio_free(chip->gpiodev->base + offset);
2622 EXPORT_SYMBOL_GPL(gpiochip_generic_free);
2625 * gpiochip_generic_config() - apply configuration for a pin
2626 * @chip: the gpiochip owning the GPIO
2627 * @offset: the offset of the GPIO to apply the configuration
2628 * @config: the configuration to be applied
2630 int gpiochip_generic_config(struct gpio_chip *chip, unsigned offset,
2631 unsigned long config)
2633 return pinctrl_gpio_set_config(chip->gpiodev->base + offset, config);
2635 EXPORT_SYMBOL_GPL(gpiochip_generic_config);
2637 #ifdef CONFIG_PINCTRL
2640 * gpiochip_add_pingroup_range() - add a range for GPIO <-> pin mapping
2641 * @chip: the gpiochip to add the range for
2642 * @pctldev: the pin controller to map to
2643 * @gpio_offset: the start offset in the current gpio_chip number space
2644 * @pin_group: name of the pin group inside the pin controller
2646 * Calling this function directly from a DeviceTree-supported
2647 * pinctrl driver is DEPRECATED. Please see Section 2.1 of
2648 * Documentation/devicetree/bindings/gpio/gpio.txt on how to
2649 * bind pinctrl and gpio drivers via the "gpio-ranges" property.
2651 int gpiochip_add_pingroup_range(struct gpio_chip *chip,
2652 struct pinctrl_dev *pctldev,
2653 unsigned int gpio_offset, const char *pin_group)
2655 struct gpio_pin_range *pin_range;
2656 struct gpio_device *gdev = chip->gpiodev;
2659 pin_range = kzalloc(sizeof(*pin_range), GFP_KERNEL);
2661 chip_err(chip, "failed to allocate pin ranges\n");
2665 /* Use local offset as range ID */
2666 pin_range->range.id = gpio_offset;
2667 pin_range->range.gc = chip;
2668 pin_range->range.name = chip->label;
2669 pin_range->range.base = gdev->base + gpio_offset;
2670 pin_range->pctldev = pctldev;
2672 ret = pinctrl_get_group_pins(pctldev, pin_group,
2673 &pin_range->range.pins,
2674 &pin_range->range.npins);
2680 pinctrl_add_gpio_range(pctldev, &pin_range->range);
2682 chip_dbg(chip, "created GPIO range %d->%d ==> %s PINGRP %s\n",
2683 gpio_offset, gpio_offset + pin_range->range.npins - 1,
2684 pinctrl_dev_get_devname(pctldev), pin_group);
2686 list_add_tail(&pin_range->node, &gdev->pin_ranges);
2690 EXPORT_SYMBOL_GPL(gpiochip_add_pingroup_range);
2693 * gpiochip_add_pin_range() - add a range for GPIO <-> pin mapping
2694 * @chip: the gpiochip to add the range for
2695 * @pinctl_name: the dev_name() of the pin controller to map to
2696 * @gpio_offset: the start offset in the current gpio_chip number space
2697 * @pin_offset: the start offset in the pin controller number space
2698 * @npins: the number of pins from the offset of each pin space (GPIO and
2699 * pin controller) to accumulate in this range
2702 * 0 on success, or a negative error-code on failure.
2704 * Calling this function directly from a DeviceTree-supported
2705 * pinctrl driver is DEPRECATED. Please see Section 2.1 of
2706 * Documentation/devicetree/bindings/gpio/gpio.txt on how to
2707 * bind pinctrl and gpio drivers via the "gpio-ranges" property.
2709 int gpiochip_add_pin_range(struct gpio_chip *chip, const char *pinctl_name,
2710 unsigned int gpio_offset, unsigned int pin_offset,
2713 struct gpio_pin_range *pin_range;
2714 struct gpio_device *gdev = chip->gpiodev;
2717 pin_range = kzalloc(sizeof(*pin_range), GFP_KERNEL);
2719 chip_err(chip, "failed to allocate pin ranges\n");
2723 /* Use local offset as range ID */
2724 pin_range->range.id = gpio_offset;
2725 pin_range->range.gc = chip;
2726 pin_range->range.name = chip->label;
2727 pin_range->range.base = gdev->base + gpio_offset;
2728 pin_range->range.pin_base = pin_offset;
2729 pin_range->range.npins = npins;
2730 pin_range->pctldev = pinctrl_find_and_add_gpio_range(pinctl_name,
2732 if (IS_ERR(pin_range->pctldev)) {
2733 ret = PTR_ERR(pin_range->pctldev);
2734 chip_err(chip, "could not create pin range\n");
2738 chip_dbg(chip, "created GPIO range %d->%d ==> %s PIN %d->%d\n",
2739 gpio_offset, gpio_offset + npins - 1,
2741 pin_offset, pin_offset + npins - 1);
2743 list_add_tail(&pin_range->node, &gdev->pin_ranges);
2747 EXPORT_SYMBOL_GPL(gpiochip_add_pin_range);
2750 * gpiochip_remove_pin_ranges() - remove all the GPIO <-> pin mappings
2751 * @chip: the chip to remove all the mappings for
2753 void gpiochip_remove_pin_ranges(struct gpio_chip *chip)
2755 struct gpio_pin_range *pin_range, *tmp;
2756 struct gpio_device *gdev = chip->gpiodev;
2758 list_for_each_entry_safe(pin_range, tmp, &gdev->pin_ranges, node) {
2759 list_del(&pin_range->node);
2760 pinctrl_remove_gpio_range(pin_range->pctldev,
2765 EXPORT_SYMBOL_GPL(gpiochip_remove_pin_ranges);
2767 #endif /* CONFIG_PINCTRL */
2769 /* These "optional" allocation calls help prevent drivers from stomping
2770 * on each other, and help provide better diagnostics in debugfs.
2771 * They're called even less than the "set direction" calls.
2773 static int gpiod_request_commit(struct gpio_desc *desc, const char *label)
2775 struct gpio_chip *chip = desc->gdev->chip;
2777 unsigned long flags;
2781 label = kstrdup_const(label, GFP_KERNEL);
2786 spin_lock_irqsave(&gpio_lock, flags);
2788 /* NOTE: gpio_request() can be called in early boot,
2789 * before IRQs are enabled, for non-sleeping (SOC) GPIOs.
2792 if (test_and_set_bit(FLAG_REQUESTED, &desc->flags) == 0) {
2793 desc_set_label(desc, label ? : "?");
2801 if (chip->request) {
2802 /* chip->request may sleep */
2803 spin_unlock_irqrestore(&gpio_lock, flags);
2804 offset = gpio_chip_hwgpio(desc);
2805 if (gpiochip_line_is_valid(chip, offset))
2806 ret = chip->request(chip, offset);
2809 spin_lock_irqsave(&gpio_lock, flags);
2812 desc_set_label(desc, NULL);
2814 clear_bit(FLAG_REQUESTED, &desc->flags);
2818 if (chip->get_direction) {
2819 /* chip->get_direction may sleep */
2820 spin_unlock_irqrestore(&gpio_lock, flags);
2821 gpiod_get_direction(desc);
2822 spin_lock_irqsave(&gpio_lock, flags);
2825 spin_unlock_irqrestore(&gpio_lock, flags);
2830 * This descriptor validation needs to be inserted verbatim into each
2831 * function taking a descriptor, so we need to use a preprocessor
2832 * macro to avoid endless duplication. If the desc is NULL it is an
2833 * optional GPIO and calls should just bail out.
2835 static int validate_desc(const struct gpio_desc *desc, const char *func)
2840 pr_warn("%s: invalid GPIO (errorpointer)\n", func);
2841 return PTR_ERR(desc);
2844 pr_warn("%s: invalid GPIO (no device)\n", func);
2847 if (!desc->gdev->chip) {
2848 dev_warn(&desc->gdev->dev,
2849 "%s: backing chip is gone\n", func);
2855 #define VALIDATE_DESC(desc) do { \
2856 int __valid = validate_desc(desc, __func__); \
2861 #define VALIDATE_DESC_VOID(desc) do { \
2862 int __valid = validate_desc(desc, __func__); \
2867 int gpiod_request(struct gpio_desc *desc, const char *label)
2869 int ret = -EPROBE_DEFER;
2870 struct gpio_device *gdev;
2872 VALIDATE_DESC(desc);
2875 if (try_module_get(gdev->owner)) {
2876 ret = gpiod_request_commit(desc, label);
2878 module_put(gdev->owner);
2880 get_device(&gdev->dev);
2884 gpiod_dbg(desc, "%s: status %d\n", __func__, ret);
2889 static bool gpiod_free_commit(struct gpio_desc *desc)
2892 unsigned long flags;
2893 struct gpio_chip *chip;
2897 gpiod_unexport(desc);
2899 spin_lock_irqsave(&gpio_lock, flags);
2901 chip = desc->gdev->chip;
2902 if (chip && test_bit(FLAG_REQUESTED, &desc->flags)) {
2904 spin_unlock_irqrestore(&gpio_lock, flags);
2905 might_sleep_if(chip->can_sleep);
2906 chip->free(chip, gpio_chip_hwgpio(desc));
2907 spin_lock_irqsave(&gpio_lock, flags);
2909 kfree_const(desc->label);
2910 desc_set_label(desc, NULL);
2911 clear_bit(FLAG_ACTIVE_LOW, &desc->flags);
2912 clear_bit(FLAG_REQUESTED, &desc->flags);
2913 clear_bit(FLAG_OPEN_DRAIN, &desc->flags);
2914 clear_bit(FLAG_OPEN_SOURCE, &desc->flags);
2915 clear_bit(FLAG_PULL_UP, &desc->flags);
2916 clear_bit(FLAG_PULL_DOWN, &desc->flags);
2917 clear_bit(FLAG_BIAS_DISABLE, &desc->flags);
2918 clear_bit(FLAG_IS_HOGGED, &desc->flags);
2922 spin_unlock_irqrestore(&gpio_lock, flags);
2926 void gpiod_free(struct gpio_desc *desc)
2928 if (desc && desc->gdev && gpiod_free_commit(desc)) {
2929 module_put(desc->gdev->owner);
2930 put_device(&desc->gdev->dev);
2932 WARN_ON(extra_checks);
2937 * gpiochip_is_requested - return string iff signal was requested
2938 * @chip: controller managing the signal
2939 * @offset: of signal within controller's 0..(ngpio - 1) range
2941 * Returns NULL if the GPIO is not currently requested, else a string.
2942 * The string returned is the label passed to gpio_request(); if none has been
2943 * passed it is a meaningless, non-NULL constant.
2945 * This function is for use by GPIO controller drivers. The label can
2946 * help with diagnostics, and knowing that the signal is used as a GPIO
2947 * can help avoid accidentally multiplexing it to another controller.
2949 const char *gpiochip_is_requested(struct gpio_chip *chip, unsigned offset)
2951 struct gpio_desc *desc;
2953 if (offset >= chip->ngpio)
2956 desc = &chip->gpiodev->descs[offset];
2958 if (test_bit(FLAG_REQUESTED, &desc->flags) == 0)
2962 EXPORT_SYMBOL_GPL(gpiochip_is_requested);
2965 * gpiochip_request_own_desc - Allow GPIO chip to request its own descriptor
2967 * @hwnum: hardware number of the GPIO for which to request the descriptor
2968 * @label: label for the GPIO
2969 * @lflags: lookup flags for this GPIO or 0 if default, this can be used to
2970 * specify things like line inversion semantics with the machine flags
2971 * such as GPIO_OUT_LOW
2972 * @dflags: descriptor request flags for this GPIO or 0 if default, this
2973 * can be used to specify consumer semantics such as open drain
2975 * Function allows GPIO chip drivers to request and use their own GPIO
2976 * descriptors via gpiolib API. Difference to gpiod_request() is that this
2977 * function will not increase reference count of the GPIO chip module. This
2978 * allows the GPIO chip module to be unloaded as needed (we assume that the
2979 * GPIO chip driver handles freeing the GPIOs it has requested).
2982 * A pointer to the GPIO descriptor, or an ERR_PTR()-encoded negative error
2985 struct gpio_desc *gpiochip_request_own_desc(struct gpio_chip *chip,
2988 enum gpio_lookup_flags lflags,
2989 enum gpiod_flags dflags)
2991 struct gpio_desc *desc = gpiochip_get_desc(chip, hwnum);
2995 chip_err(chip, "failed to get GPIO descriptor\n");
2999 ret = gpiod_request_commit(desc, label);
3001 return ERR_PTR(ret);
3003 ret = gpiod_configure_flags(desc, label, lflags, dflags);
3005 chip_err(chip, "setup of own GPIO %s failed\n", label);
3006 gpiod_free_commit(desc);
3007 return ERR_PTR(ret);
3012 EXPORT_SYMBOL_GPL(gpiochip_request_own_desc);
3015 * gpiochip_free_own_desc - Free GPIO requested by the chip driver
3016 * @desc: GPIO descriptor to free
3018 * Function frees the given GPIO requested previously with
3019 * gpiochip_request_own_desc().
3021 void gpiochip_free_own_desc(struct gpio_desc *desc)
3024 gpiod_free_commit(desc);
3026 EXPORT_SYMBOL_GPL(gpiochip_free_own_desc);
3029 * Drivers MUST set GPIO direction before making get/set calls. In
3030 * some cases this is done in early boot, before IRQs are enabled.
3032 * As a rule these aren't called more than once (except for drivers
3033 * using the open-drain emulation idiom) so these are natural places
3034 * to accumulate extra debugging checks. Note that we can't (yet)
3035 * rely on gpio_request() having been called beforehand.
3038 static int gpio_set_config(struct gpio_chip *gc, unsigned int offset,
3039 enum pin_config_param mode)
3041 if (!gc->set_config)
3044 return gc->set_config(gc, offset, mode);
3047 static int gpio_set_bias(struct gpio_chip *chip, struct gpio_desc *desc)
3052 if (test_bit(FLAG_BIAS_DISABLE, &desc->flags))
3053 bias = PIN_CONFIG_BIAS_DISABLE;
3054 else if (test_bit(FLAG_PULL_UP, &desc->flags))
3055 bias = PIN_CONFIG_BIAS_PULL_UP;
3056 else if (test_bit(FLAG_PULL_DOWN, &desc->flags))
3057 bias = PIN_CONFIG_BIAS_PULL_DOWN;
3060 ret = gpio_set_config(chip, gpio_chip_hwgpio(desc), bias);
3061 if (ret != -ENOTSUPP)
3068 * gpiod_direction_input - set the GPIO direction to input
3069 * @desc: GPIO to set to input
3071 * Set the direction of the passed GPIO to input, such as gpiod_get_value() can
3072 * be called safely on it.
3074 * Return 0 in case of success, else an error code.
3076 int gpiod_direction_input(struct gpio_desc *desc)
3078 struct gpio_chip *chip;
3081 VALIDATE_DESC(desc);
3082 chip = desc->gdev->chip;
3085 * It is legal to have no .get() and .direction_input() specified if
3086 * the chip is output-only, but you can't specify .direction_input()
3087 * and not support the .get() operation, that doesn't make sense.
3089 if (!chip->get && chip->direction_input) {
3091 "%s: missing get() but have direction_input()\n",
3097 * If we have a .direction_input() callback, things are simple,
3098 * just call it. Else we are some input-only chip so try to check the
3099 * direction (if .get_direction() is supported) else we silently
3100 * assume we are in input mode after this.
3102 if (chip->direction_input) {
3103 ret = chip->direction_input(chip, gpio_chip_hwgpio(desc));
3104 } else if (chip->get_direction &&
3105 (chip->get_direction(chip, gpio_chip_hwgpio(desc)) != 1)) {
3107 "%s: missing direction_input() operation and line is output\n",
3112 clear_bit(FLAG_IS_OUT, &desc->flags);
3113 ret = gpio_set_bias(chip, desc);
3116 trace_gpio_direction(desc_to_gpio(desc), 1, ret);
3120 EXPORT_SYMBOL_GPL(gpiod_direction_input);
3122 static int gpiod_direction_output_raw_commit(struct gpio_desc *desc, int value)
3124 struct gpio_chip *gc = desc->gdev->chip;
3129 * It's OK not to specify .direction_output() if the gpiochip is
3130 * output-only, but if there is then not even a .set() operation it
3131 * is pretty tricky to drive the output line.
3133 if (!gc->set && !gc->direction_output) {
3135 "%s: missing set() and direction_output() operations\n",
3140 if (gc->direction_output) {
3141 ret = gc->direction_output(gc, gpio_chip_hwgpio(desc), val);
3143 /* Check that we are in output mode if we can */
3144 if (gc->get_direction &&
3145 gc->get_direction(gc, gpio_chip_hwgpio(desc))) {
3147 "%s: missing direction_output() operation\n",
3152 * If we can't actively set the direction, we are some
3153 * output-only chip, so just drive the output as desired.
3155 gc->set(gc, gpio_chip_hwgpio(desc), val);
3159 set_bit(FLAG_IS_OUT, &desc->flags);
3160 trace_gpio_value(desc_to_gpio(desc), 0, val);
3161 trace_gpio_direction(desc_to_gpio(desc), 0, ret);
3166 * gpiod_direction_output_raw - set the GPIO direction to output
3167 * @desc: GPIO to set to output
3168 * @value: initial output value of the GPIO
3170 * Set the direction of the passed GPIO to output, such as gpiod_set_value() can
3171 * be called safely on it. The initial value of the output must be specified
3172 * as raw value on the physical line without regard for the ACTIVE_LOW status.
3174 * Return 0 in case of success, else an error code.
3176 int gpiod_direction_output_raw(struct gpio_desc *desc, int value)
3178 VALIDATE_DESC(desc);
3179 return gpiod_direction_output_raw_commit(desc, value);
3181 EXPORT_SYMBOL_GPL(gpiod_direction_output_raw);
3184 * gpiod_direction_output - set the GPIO direction to output
3185 * @desc: GPIO to set to output
3186 * @value: initial output value of the GPIO
3188 * Set the direction of the passed GPIO to output, such as gpiod_set_value() can
3189 * be called safely on it. The initial value of the output must be specified
3190 * as the logical value of the GPIO, i.e. taking its ACTIVE_LOW status into
3193 * Return 0 in case of success, else an error code.
3195 int gpiod_direction_output(struct gpio_desc *desc, int value)
3197 struct gpio_chip *gc;
3200 VALIDATE_DESC(desc);
3201 if (test_bit(FLAG_ACTIVE_LOW, &desc->flags))
3206 /* GPIOs used for enabled IRQs shall not be set as output */
3207 if (test_bit(FLAG_USED_AS_IRQ, &desc->flags) &&
3208 test_bit(FLAG_IRQ_IS_ENABLED, &desc->flags)) {
3210 "%s: tried to set a GPIO tied to an IRQ as output\n",
3215 gc = desc->gdev->chip;
3216 if (test_bit(FLAG_OPEN_DRAIN, &desc->flags)) {
3217 /* First see if we can enable open drain in hardware */
3218 ret = gpio_set_config(gc, gpio_chip_hwgpio(desc),
3219 PIN_CONFIG_DRIVE_OPEN_DRAIN);
3221 goto set_output_value;
3222 /* Emulate open drain by not actively driving the line high */
3224 ret = gpiod_direction_input(desc);
3225 goto set_output_flag;
3228 else if (test_bit(FLAG_OPEN_SOURCE, &desc->flags)) {
3229 ret = gpio_set_config(gc, gpio_chip_hwgpio(desc),
3230 PIN_CONFIG_DRIVE_OPEN_SOURCE);
3232 goto set_output_value;
3233 /* Emulate open source by not actively driving the line low */
3235 ret = gpiod_direction_input(desc);
3236 goto set_output_flag;
3239 gpio_set_config(gc, gpio_chip_hwgpio(desc),
3240 PIN_CONFIG_DRIVE_PUSH_PULL);
3244 ret = gpio_set_bias(gc, desc);
3247 return gpiod_direction_output_raw_commit(desc, value);
3251 * When emulating open-source or open-drain functionalities by not
3252 * actively driving the line (setting mode to input) we still need to
3253 * set the IS_OUT flag or otherwise we won't be able to set the line
3257 set_bit(FLAG_IS_OUT, &desc->flags);
3260 EXPORT_SYMBOL_GPL(gpiod_direction_output);
3263 * gpiod_set_debounce - sets @debounce time for a GPIO
3264 * @desc: descriptor of the GPIO for which to set debounce time
3265 * @debounce: debounce time in microseconds
3268 * 0 on success, %-ENOTSUPP if the controller doesn't support setting the
3271 int gpiod_set_debounce(struct gpio_desc *desc, unsigned debounce)
3273 struct gpio_chip *chip;
3274 unsigned long config;
3276 VALIDATE_DESC(desc);
3277 chip = desc->gdev->chip;
3279 config = pinconf_to_config_packed(PIN_CONFIG_INPUT_DEBOUNCE, debounce);
3280 return gpio_set_config(chip, gpio_chip_hwgpio(desc), config);
3282 EXPORT_SYMBOL_GPL(gpiod_set_debounce);
3285 * gpiod_set_transitory - Lose or retain GPIO state on suspend or reset
3286 * @desc: descriptor of the GPIO for which to configure persistence
3287 * @transitory: True to lose state on suspend or reset, false for persistence
3290 * 0 on success, otherwise a negative error code.
3292 int gpiod_set_transitory(struct gpio_desc *desc, bool transitory)
3294 struct gpio_chip *chip;
3295 unsigned long packed;
3299 VALIDATE_DESC(desc);
3301 * Handle FLAG_TRANSITORY first, enabling queries to gpiolib for
3302 * persistence state.
3304 assign_bit(FLAG_TRANSITORY, &desc->flags, transitory);
3306 /* If the driver supports it, set the persistence state now */
3307 chip = desc->gdev->chip;
3308 if (!chip->set_config)
3311 packed = pinconf_to_config_packed(PIN_CONFIG_PERSIST_STATE,
3313 gpio = gpio_chip_hwgpio(desc);
3314 rc = gpio_set_config(chip, gpio, packed);
3315 if (rc == -ENOTSUPP) {
3316 dev_dbg(&desc->gdev->dev, "Persistence not supported for GPIO %d\n",
3323 EXPORT_SYMBOL_GPL(gpiod_set_transitory);
3326 * gpiod_is_active_low - test whether a GPIO is active-low or not
3327 * @desc: the gpio descriptor to test
3329 * Returns 1 if the GPIO is active-low, 0 otherwise.
3331 int gpiod_is_active_low(const struct gpio_desc *desc)
3333 VALIDATE_DESC(desc);
3334 return test_bit(FLAG_ACTIVE_LOW, &desc->flags);
3336 EXPORT_SYMBOL_GPL(gpiod_is_active_low);
3339 * gpiod_toggle_active_low - toggle whether a GPIO is active-low or not
3340 * @desc: the gpio descriptor to change
3342 void gpiod_toggle_active_low(struct gpio_desc *desc)
3344 VALIDATE_DESC_VOID(desc);
3345 change_bit(FLAG_ACTIVE_LOW, &desc->flags);
3347 EXPORT_SYMBOL_GPL(gpiod_toggle_active_low);
3349 /* I/O calls are only valid after configuration completed; the relevant
3350 * "is this a valid GPIO" error checks should already have been done.
3352 * "Get" operations are often inlinable as reading a pin value register,
3353 * and masking the relevant bit in that register.
3355 * When "set" operations are inlinable, they involve writing that mask to
3356 * one register to set a low value, or a different register to set it high.
3357 * Otherwise locking is needed, so there may be little value to inlining.
3359 *------------------------------------------------------------------------
3361 * IMPORTANT!!! The hot paths -- get/set value -- assume that callers
3362 * have requested the GPIO. That can include implicit requesting by
3363 * a direction setting call. Marking a gpio as requested locks its chip
3364 * in memory, guaranteeing that these table lookups need no more locking
3365 * and that gpiochip_remove() will fail.
3367 * REVISIT when debugging, consider adding some instrumentation to ensure
3368 * that the GPIO was actually requested.
3371 static int gpiod_get_raw_value_commit(const struct gpio_desc *desc)
3373 struct gpio_chip *chip;
3377 chip = desc->gdev->chip;
3378 offset = gpio_chip_hwgpio(desc);
3379 value = chip->get ? chip->get(chip, offset) : -EIO;
3380 value = value < 0 ? value : !!value;
3381 trace_gpio_value(desc_to_gpio(desc), 1, value);
3385 static int gpio_chip_get_multiple(struct gpio_chip *chip,
3386 unsigned long *mask, unsigned long *bits)
3388 if (chip->get_multiple) {
3389 return chip->get_multiple(chip, mask, bits);
3390 } else if (chip->get) {
3393 for_each_set_bit(i, mask, chip->ngpio) {
3394 value = chip->get(chip, i);
3397 __assign_bit(i, bits, value);
3404 int gpiod_get_array_value_complex(bool raw, bool can_sleep,
3405 unsigned int array_size,
3406 struct gpio_desc **desc_array,
3407 struct gpio_array *array_info,
3408 unsigned long *value_bitmap)
3413 * Validate array_info against desc_array and its size.
3414 * It should immediately follow desc_array if both
3415 * have been obtained from the same gpiod_get_array() call.
3417 if (array_info && array_info->desc == desc_array &&
3418 array_size <= array_info->size &&
3419 (void *)array_info == desc_array + array_info->size) {
3421 WARN_ON(array_info->chip->can_sleep);
3423 ret = gpio_chip_get_multiple(array_info->chip,
3424 array_info->get_mask,
3429 if (!raw && !bitmap_empty(array_info->invert_mask, array_size))
3430 bitmap_xor(value_bitmap, value_bitmap,
3431 array_info->invert_mask, array_size);
3433 if (bitmap_full(array_info->get_mask, array_size))
3436 i = find_first_zero_bit(array_info->get_mask, array_size);
3441 while (i < array_size) {
3442 struct gpio_chip *chip = desc_array[i]->gdev->chip;
3443 unsigned long fastpath[2 * BITS_TO_LONGS(FASTPATH_NGPIO)];
3444 unsigned long *mask, *bits;
3447 if (likely(chip->ngpio <= FASTPATH_NGPIO)) {
3450 mask = kmalloc_array(2 * BITS_TO_LONGS(chip->ngpio),
3452 can_sleep ? GFP_KERNEL : GFP_ATOMIC);
3457 bits = mask + BITS_TO_LONGS(chip->ngpio);
3458 bitmap_zero(mask, chip->ngpio);
3461 WARN_ON(chip->can_sleep);
3463 /* collect all inputs belonging to the same chip */
3466 const struct gpio_desc *desc = desc_array[i];
3467 int hwgpio = gpio_chip_hwgpio(desc);
3469 __set_bit(hwgpio, mask);
3473 i = find_next_zero_bit(array_info->get_mask,
3475 } while ((i < array_size) &&
3476 (desc_array[i]->gdev->chip == chip));
3478 ret = gpio_chip_get_multiple(chip, mask, bits);
3480 if (mask != fastpath)
3485 for (j = first; j < i; ) {
3486 const struct gpio_desc *desc = desc_array[j];
3487 int hwgpio = gpio_chip_hwgpio(desc);
3488 int value = test_bit(hwgpio, bits);
3490 if (!raw && test_bit(FLAG_ACTIVE_LOW, &desc->flags))
3492 __assign_bit(j, value_bitmap, value);
3493 trace_gpio_value(desc_to_gpio(desc), 1, value);
3497 j = find_next_zero_bit(array_info->get_mask, i,
3501 if (mask != fastpath)
3508 * gpiod_get_raw_value() - return a gpio's raw value
3509 * @desc: gpio whose value will be returned
3511 * Return the GPIO's raw value, i.e. the value of the physical line disregarding
3512 * its ACTIVE_LOW status, or negative errno on failure.
3514 * This function can be called from contexts where we cannot sleep, and will
3515 * complain if the GPIO chip functions potentially sleep.
3517 int gpiod_get_raw_value(const struct gpio_desc *desc)
3519 VALIDATE_DESC(desc);
3520 /* Should be using gpiod_get_raw_value_cansleep() */
3521 WARN_ON(desc->gdev->chip->can_sleep);
3522 return gpiod_get_raw_value_commit(desc);
3524 EXPORT_SYMBOL_GPL(gpiod_get_raw_value);
3527 * gpiod_get_value() - return a gpio's value
3528 * @desc: gpio whose value will be returned
3530 * Return the GPIO's logical value, i.e. taking the ACTIVE_LOW status into
3531 * account, or negative errno on failure.
3533 * This function can be called from contexts where we cannot sleep, and will
3534 * complain if the GPIO chip functions potentially sleep.
3536 int gpiod_get_value(const struct gpio_desc *desc)
3540 VALIDATE_DESC(desc);
3541 /* Should be using gpiod_get_value_cansleep() */
3542 WARN_ON(desc->gdev->chip->can_sleep);
3544 value = gpiod_get_raw_value_commit(desc);
3548 if (test_bit(FLAG_ACTIVE_LOW, &desc->flags))
3553 EXPORT_SYMBOL_GPL(gpiod_get_value);
3556 * gpiod_get_raw_array_value() - read raw values from an array of GPIOs
3557 * @array_size: number of elements in the descriptor array / value bitmap
3558 * @desc_array: array of GPIO descriptors whose values will be read
3559 * @array_info: information on applicability of fast bitmap processing path
3560 * @value_bitmap: bitmap to store the read values
3562 * Read the raw values of the GPIOs, i.e. the values of the physical lines
3563 * without regard for their ACTIVE_LOW status. Return 0 in case of success,
3564 * else an error code.
3566 * This function can be called from contexts where we cannot sleep,
3567 * and it will complain if the GPIO chip functions potentially sleep.
3569 int gpiod_get_raw_array_value(unsigned int array_size,
3570 struct gpio_desc **desc_array,
3571 struct gpio_array *array_info,
3572 unsigned long *value_bitmap)
3576 return gpiod_get_array_value_complex(true, false, array_size,
3577 desc_array, array_info,
3580 EXPORT_SYMBOL_GPL(gpiod_get_raw_array_value);
3583 * gpiod_get_array_value() - read values from an array of GPIOs
3584 * @array_size: number of elements in the descriptor array / value bitmap
3585 * @desc_array: array of GPIO descriptors whose values will be read
3586 * @array_info: information on applicability of fast bitmap processing path
3587 * @value_bitmap: bitmap to store the read values
3589 * Read the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status
3590 * into account. Return 0 in case of success, else an error code.
3592 * This function can be called from contexts where we cannot sleep,
3593 * and it will complain if the GPIO chip functions potentially sleep.
3595 int gpiod_get_array_value(unsigned int array_size,
3596 struct gpio_desc **desc_array,
3597 struct gpio_array *array_info,
3598 unsigned long *value_bitmap)
3602 return gpiod_get_array_value_complex(false, false, array_size,
3603 desc_array, array_info,
3606 EXPORT_SYMBOL_GPL(gpiod_get_array_value);
3609 * gpio_set_open_drain_value_commit() - Set the open drain gpio's value.
3610 * @desc: gpio descriptor whose state need to be set.
3611 * @value: Non-zero for setting it HIGH otherwise it will set to LOW.
3613 static void gpio_set_open_drain_value_commit(struct gpio_desc *desc, bool value)
3616 struct gpio_chip *chip = desc->gdev->chip;
3617 int offset = gpio_chip_hwgpio(desc);
3620 ret = chip->direction_input(chip, offset);
3622 ret = chip->direction_output(chip, offset, 0);
3624 set_bit(FLAG_IS_OUT, &desc->flags);
3626 trace_gpio_direction(desc_to_gpio(desc), value, ret);
3629 "%s: Error in set_value for open drain err %d\n",
3634 * _gpio_set_open_source_value() - Set the open source gpio's value.
3635 * @desc: gpio descriptor whose state need to be set.
3636 * @value: Non-zero for setting it HIGH otherwise it will set to LOW.
3638 static void gpio_set_open_source_value_commit(struct gpio_desc *desc, bool value)
3641 struct gpio_chip *chip = desc->gdev->chip;
3642 int offset = gpio_chip_hwgpio(desc);
3645 ret = chip->direction_output(chip, offset, 1);
3647 set_bit(FLAG_IS_OUT, &desc->flags);
3649 ret = chip->direction_input(chip, offset);
3651 trace_gpio_direction(desc_to_gpio(desc), !value, ret);
3654 "%s: Error in set_value for open source err %d\n",
3658 static void gpiod_set_raw_value_commit(struct gpio_desc *desc, bool value)
3660 struct gpio_chip *chip;
3662 chip = desc->gdev->chip;
3663 trace_gpio_value(desc_to_gpio(desc), 0, value);
3664 chip->set(chip, gpio_chip_hwgpio(desc), value);
3668 * set multiple outputs on the same chip;
3669 * use the chip's set_multiple function if available;
3670 * otherwise set the outputs sequentially;
3671 * @mask: bit mask array; one bit per output; BITS_PER_LONG bits per word
3672 * defines which outputs are to be changed
3673 * @bits: bit value array; one bit per output; BITS_PER_LONG bits per word
3674 * defines the values the outputs specified by mask are to be set to
3676 static void gpio_chip_set_multiple(struct gpio_chip *chip,
3677 unsigned long *mask, unsigned long *bits)
3679 if (chip->set_multiple) {
3680 chip->set_multiple(chip, mask, bits);
3684 /* set outputs if the corresponding mask bit is set */
3685 for_each_set_bit(i, mask, chip->ngpio)
3686 chip->set(chip, i, test_bit(i, bits));
3690 int gpiod_set_array_value_complex(bool raw, bool can_sleep,
3691 unsigned int array_size,
3692 struct gpio_desc **desc_array,
3693 struct gpio_array *array_info,
3694 unsigned long *value_bitmap)
3699 * Validate array_info against desc_array and its size.
3700 * It should immediately follow desc_array if both
3701 * have been obtained from the same gpiod_get_array() call.
3703 if (array_info && array_info->desc == desc_array &&
3704 array_size <= array_info->size &&
3705 (void *)array_info == desc_array + array_info->size) {
3707 WARN_ON(array_info->chip->can_sleep);
3709 if (!raw && !bitmap_empty(array_info->invert_mask, array_size))
3710 bitmap_xor(value_bitmap, value_bitmap,
3711 array_info->invert_mask, array_size);
3713 gpio_chip_set_multiple(array_info->chip, array_info->set_mask,
3716 if (bitmap_full(array_info->set_mask, array_size))
3719 i = find_first_zero_bit(array_info->set_mask, array_size);
3724 while (i < array_size) {
3725 struct gpio_chip *chip = desc_array[i]->gdev->chip;
3726 unsigned long fastpath[2 * BITS_TO_LONGS(FASTPATH_NGPIO)];
3727 unsigned long *mask, *bits;
3730 if (likely(chip->ngpio <= FASTPATH_NGPIO)) {
3733 mask = kmalloc_array(2 * BITS_TO_LONGS(chip->ngpio),
3735 can_sleep ? GFP_KERNEL : GFP_ATOMIC);
3740 bits = mask + BITS_TO_LONGS(chip->ngpio);
3741 bitmap_zero(mask, chip->ngpio);
3744 WARN_ON(chip->can_sleep);
3747 struct gpio_desc *desc = desc_array[i];
3748 int hwgpio = gpio_chip_hwgpio(desc);
3749 int value = test_bit(i, value_bitmap);
3752 * Pins applicable for fast input but not for
3753 * fast output processing may have been already
3754 * inverted inside the fast path, skip them.
3756 if (!raw && !(array_info &&
3757 test_bit(i, array_info->invert_mask)) &&
3758 test_bit(FLAG_ACTIVE_LOW, &desc->flags))
3760 trace_gpio_value(desc_to_gpio(desc), 0, value);
3762 * collect all normal outputs belonging to the same chip
3763 * open drain and open source outputs are set individually
3765 if (test_bit(FLAG_OPEN_DRAIN, &desc->flags) && !raw) {
3766 gpio_set_open_drain_value_commit(desc, value);
3767 } else if (test_bit(FLAG_OPEN_SOURCE, &desc->flags) && !raw) {
3768 gpio_set_open_source_value_commit(desc, value);
3770 __set_bit(hwgpio, mask);
3771 __assign_bit(hwgpio, bits, value);
3777 i = find_next_zero_bit(array_info->set_mask,
3779 } while ((i < array_size) &&
3780 (desc_array[i]->gdev->chip == chip));
3781 /* push collected bits to outputs */
3783 gpio_chip_set_multiple(chip, mask, bits);
3785 if (mask != fastpath)
3792 * gpiod_set_raw_value() - assign a gpio's raw value
3793 * @desc: gpio whose value will be assigned
3794 * @value: value to assign
3796 * Set the raw value of the GPIO, i.e. the value of its physical line without
3797 * regard for its ACTIVE_LOW status.
3799 * This function can be called from contexts where we cannot sleep, and will
3800 * complain if the GPIO chip functions potentially sleep.
3802 void gpiod_set_raw_value(struct gpio_desc *desc, int value)
3804 VALIDATE_DESC_VOID(desc);
3805 /* Should be using gpiod_set_raw_value_cansleep() */
3806 WARN_ON(desc->gdev->chip->can_sleep);
3807 gpiod_set_raw_value_commit(desc, value);
3809 EXPORT_SYMBOL_GPL(gpiod_set_raw_value);
3812 * gpiod_set_value_nocheck() - set a GPIO line value without checking
3813 * @desc: the descriptor to set the value on
3814 * @value: value to set
3816 * This sets the value of a GPIO line backing a descriptor, applying
3817 * different semantic quirks like active low and open drain/source
3820 static void gpiod_set_value_nocheck(struct gpio_desc *desc, int value)
3822 if (test_bit(FLAG_ACTIVE_LOW, &desc->flags))
3824 if (test_bit(FLAG_OPEN_DRAIN, &desc->flags))
3825 gpio_set_open_drain_value_commit(desc, value);
3826 else if (test_bit(FLAG_OPEN_SOURCE, &desc->flags))
3827 gpio_set_open_source_value_commit(desc, value);
3829 gpiod_set_raw_value_commit(desc, value);
3833 * gpiod_set_value() - assign a gpio's value
3834 * @desc: gpio whose value will be assigned
3835 * @value: value to assign
3837 * Set the logical value of the GPIO, i.e. taking its ACTIVE_LOW,
3838 * OPEN_DRAIN and OPEN_SOURCE flags into account.
3840 * This function can be called from contexts where we cannot sleep, and will
3841 * complain if the GPIO chip functions potentially sleep.
3843 void gpiod_set_value(struct gpio_desc *desc, int value)
3845 VALIDATE_DESC_VOID(desc);
3846 /* Should be using gpiod_set_value_cansleep() */
3847 WARN_ON(desc->gdev->chip->can_sleep);
3848 gpiod_set_value_nocheck(desc, value);
3850 EXPORT_SYMBOL_GPL(gpiod_set_value);
3853 * gpiod_set_raw_array_value() - assign values to an array of GPIOs
3854 * @array_size: number of elements in the descriptor array / value bitmap
3855 * @desc_array: array of GPIO descriptors whose values will be assigned
3856 * @array_info: information on applicability of fast bitmap processing path
3857 * @value_bitmap: bitmap of values to assign
3859 * Set the raw values of the GPIOs, i.e. the values of the physical lines
3860 * without regard for their ACTIVE_LOW status.
3862 * This function can be called from contexts where we cannot sleep, and will
3863 * complain if the GPIO chip functions potentially sleep.
3865 int gpiod_set_raw_array_value(unsigned int array_size,
3866 struct gpio_desc **desc_array,
3867 struct gpio_array *array_info,
3868 unsigned long *value_bitmap)
3872 return gpiod_set_array_value_complex(true, false, array_size,
3873 desc_array, array_info, value_bitmap);
3875 EXPORT_SYMBOL_GPL(gpiod_set_raw_array_value);
3878 * gpiod_set_array_value() - assign values to an array of GPIOs
3879 * @array_size: number of elements in the descriptor array / value bitmap
3880 * @desc_array: array of GPIO descriptors whose values will be assigned
3881 * @array_info: information on applicability of fast bitmap processing path
3882 * @value_bitmap: bitmap of values to assign
3884 * Set the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status
3887 * This function can be called from contexts where we cannot sleep, and will
3888 * complain if the GPIO chip functions potentially sleep.
3890 int gpiod_set_array_value(unsigned int array_size,
3891 struct gpio_desc **desc_array,
3892 struct gpio_array *array_info,
3893 unsigned long *value_bitmap)
3897 return gpiod_set_array_value_complex(false, false, array_size,
3898 desc_array, array_info,
3901 EXPORT_SYMBOL_GPL(gpiod_set_array_value);
3904 * gpiod_cansleep() - report whether gpio value access may sleep
3905 * @desc: gpio to check
3908 int gpiod_cansleep(const struct gpio_desc *desc)
3910 VALIDATE_DESC(desc);
3911 return desc->gdev->chip->can_sleep;
3913 EXPORT_SYMBOL_GPL(gpiod_cansleep);
3916 * gpiod_set_consumer_name() - set the consumer name for the descriptor
3917 * @desc: gpio to set the consumer name on
3918 * @name: the new consumer name
3920 int gpiod_set_consumer_name(struct gpio_desc *desc, const char *name)
3922 VALIDATE_DESC(desc);
3924 name = kstrdup_const(name, GFP_KERNEL);
3929 kfree_const(desc->label);
3930 desc_set_label(desc, name);
3934 EXPORT_SYMBOL_GPL(gpiod_set_consumer_name);
3937 * gpiod_to_irq() - return the IRQ corresponding to a GPIO
3938 * @desc: gpio whose IRQ will be returned (already requested)
3940 * Return the IRQ corresponding to the passed GPIO, or an error code in case of
3943 int gpiod_to_irq(const struct gpio_desc *desc)
3945 struct gpio_chip *chip;
3949 * Cannot VALIDATE_DESC() here as gpiod_to_irq() consumer semantics
3950 * requires this function to not return zero on an invalid descriptor
3951 * but rather a negative error number.
3953 if (!desc || IS_ERR(desc) || !desc->gdev || !desc->gdev->chip)
3956 chip = desc->gdev->chip;
3957 offset = gpio_chip_hwgpio(desc);
3959 int retirq = chip->to_irq(chip, offset);
3961 /* Zero means NO_IRQ */
3969 EXPORT_SYMBOL_GPL(gpiod_to_irq);
3972 * gpiochip_lock_as_irq() - lock a GPIO to be used as IRQ
3973 * @chip: the chip the GPIO to lock belongs to
3974 * @offset: the offset of the GPIO to lock as IRQ
3976 * This is used directly by GPIO drivers that want to lock down
3977 * a certain GPIO line to be used for IRQs.
3979 int gpiochip_lock_as_irq(struct gpio_chip *chip, unsigned int offset)
3981 struct gpio_desc *desc;
3983 desc = gpiochip_get_desc(chip, offset);
3985 return PTR_ERR(desc);
3988 * If it's fast: flush the direction setting if something changed
3991 if (!chip->can_sleep && chip->get_direction) {
3992 int dir = gpiod_get_direction(desc);
3995 chip_err(chip, "%s: cannot get GPIO direction\n",
4001 if (test_bit(FLAG_IS_OUT, &desc->flags)) {
4003 "%s: tried to flag a GPIO set as output for IRQ\n",
4008 set_bit(FLAG_USED_AS_IRQ, &desc->flags);
4009 set_bit(FLAG_IRQ_IS_ENABLED, &desc->flags);
4012 * If the consumer has not set up a label (such as when the
4013 * IRQ is referenced from .to_irq()) we set up a label here
4014 * so it is clear this is used as an interrupt.
4017 desc_set_label(desc, "interrupt");
4021 EXPORT_SYMBOL_GPL(gpiochip_lock_as_irq);
4024 * gpiochip_unlock_as_irq() - unlock a GPIO used as IRQ
4025 * @chip: the chip the GPIO to lock belongs to
4026 * @offset: the offset of the GPIO to lock as IRQ
4028 * This is used directly by GPIO drivers that want to indicate
4029 * that a certain GPIO is no longer used exclusively for IRQ.
4031 void gpiochip_unlock_as_irq(struct gpio_chip *chip, unsigned int offset)
4033 struct gpio_desc *desc;
4035 desc = gpiochip_get_desc(chip, offset);
4039 clear_bit(FLAG_USED_AS_IRQ, &desc->flags);
4040 clear_bit(FLAG_IRQ_IS_ENABLED, &desc->flags);
4042 /* If we only had this marking, erase it */
4043 if (desc->label && !strcmp(desc->label, "interrupt"))
4044 desc_set_label(desc, NULL);
4046 EXPORT_SYMBOL_GPL(gpiochip_unlock_as_irq);
4048 void gpiochip_disable_irq(struct gpio_chip *chip, unsigned int offset)
4050 struct gpio_desc *desc = gpiochip_get_desc(chip, offset);
4052 if (!IS_ERR(desc) &&
4053 !WARN_ON(!test_bit(FLAG_USED_AS_IRQ, &desc->flags)))
4054 clear_bit(FLAG_IRQ_IS_ENABLED, &desc->flags);
4056 EXPORT_SYMBOL_GPL(gpiochip_disable_irq);
4058 void gpiochip_enable_irq(struct gpio_chip *chip, unsigned int offset)
4060 struct gpio_desc *desc = gpiochip_get_desc(chip, offset);
4062 if (!IS_ERR(desc) &&
4063 !WARN_ON(!test_bit(FLAG_USED_AS_IRQ, &desc->flags))) {
4064 WARN_ON(test_bit(FLAG_IS_OUT, &desc->flags));
4065 set_bit(FLAG_IRQ_IS_ENABLED, &desc->flags);
4068 EXPORT_SYMBOL_GPL(gpiochip_enable_irq);
4070 bool gpiochip_line_is_irq(struct gpio_chip *chip, unsigned int offset)
4072 if (offset >= chip->ngpio)
4075 return test_bit(FLAG_USED_AS_IRQ, &chip->gpiodev->descs[offset].flags);
4077 EXPORT_SYMBOL_GPL(gpiochip_line_is_irq);
4079 int gpiochip_reqres_irq(struct gpio_chip *chip, unsigned int offset)
4083 if (!try_module_get(chip->gpiodev->owner))
4086 ret = gpiochip_lock_as_irq(chip, offset);
4088 chip_err(chip, "unable to lock HW IRQ %u for IRQ\n", offset);
4089 module_put(chip->gpiodev->owner);
4094 EXPORT_SYMBOL_GPL(gpiochip_reqres_irq);
4096 void gpiochip_relres_irq(struct gpio_chip *chip, unsigned int offset)
4098 gpiochip_unlock_as_irq(chip, offset);
4099 module_put(chip->gpiodev->owner);
4101 EXPORT_SYMBOL_GPL(gpiochip_relres_irq);
4103 bool gpiochip_line_is_open_drain(struct gpio_chip *chip, unsigned int offset)
4105 if (offset >= chip->ngpio)
4108 return test_bit(FLAG_OPEN_DRAIN, &chip->gpiodev->descs[offset].flags);
4110 EXPORT_SYMBOL_GPL(gpiochip_line_is_open_drain);
4112 bool gpiochip_line_is_open_source(struct gpio_chip *chip, unsigned int offset)
4114 if (offset >= chip->ngpio)
4117 return test_bit(FLAG_OPEN_SOURCE, &chip->gpiodev->descs[offset].flags);
4119 EXPORT_SYMBOL_GPL(gpiochip_line_is_open_source);
4121 bool gpiochip_line_is_persistent(struct gpio_chip *chip, unsigned int offset)
4123 if (offset >= chip->ngpio)
4126 return !test_bit(FLAG_TRANSITORY, &chip->gpiodev->descs[offset].flags);
4128 EXPORT_SYMBOL_GPL(gpiochip_line_is_persistent);
4131 * gpiod_get_raw_value_cansleep() - return a gpio's raw value
4132 * @desc: gpio whose value will be returned
4134 * Return the GPIO's raw value, i.e. the value of the physical line disregarding
4135 * its ACTIVE_LOW status, or negative errno on failure.
4137 * This function is to be called from contexts that can sleep.
4139 int gpiod_get_raw_value_cansleep(const struct gpio_desc *desc)
4141 might_sleep_if(extra_checks);
4142 VALIDATE_DESC(desc);
4143 return gpiod_get_raw_value_commit(desc);
4145 EXPORT_SYMBOL_GPL(gpiod_get_raw_value_cansleep);
4148 * gpiod_get_value_cansleep() - return a gpio's value
4149 * @desc: gpio whose value will be returned
4151 * Return the GPIO's logical value, i.e. taking the ACTIVE_LOW status into
4152 * account, or negative errno on failure.
4154 * This function is to be called from contexts that can sleep.
4156 int gpiod_get_value_cansleep(const struct gpio_desc *desc)
4160 might_sleep_if(extra_checks);
4161 VALIDATE_DESC(desc);
4162 value = gpiod_get_raw_value_commit(desc);
4166 if (test_bit(FLAG_ACTIVE_LOW, &desc->flags))
4171 EXPORT_SYMBOL_GPL(gpiod_get_value_cansleep);
4174 * gpiod_get_raw_array_value_cansleep() - read raw values from an array of GPIOs
4175 * @array_size: number of elements in the descriptor array / value bitmap
4176 * @desc_array: array of GPIO descriptors whose values will be read
4177 * @array_info: information on applicability of fast bitmap processing path
4178 * @value_bitmap: bitmap to store the read values
4180 * Read the raw values of the GPIOs, i.e. the values of the physical lines
4181 * without regard for their ACTIVE_LOW status. Return 0 in case of success,
4182 * else an error code.
4184 * This function is to be called from contexts that can sleep.
4186 int gpiod_get_raw_array_value_cansleep(unsigned int array_size,
4187 struct gpio_desc **desc_array,
4188 struct gpio_array *array_info,
4189 unsigned long *value_bitmap)
4191 might_sleep_if(extra_checks);
4194 return gpiod_get_array_value_complex(true, true, array_size,
4195 desc_array, array_info,
4198 EXPORT_SYMBOL_GPL(gpiod_get_raw_array_value_cansleep);
4201 * gpiod_get_array_value_cansleep() - read values from an array of GPIOs
4202 * @array_size: number of elements in the descriptor array / value bitmap
4203 * @desc_array: array of GPIO descriptors whose values will be read
4204 * @array_info: information on applicability of fast bitmap processing path
4205 * @value_bitmap: bitmap to store the read values
4207 * Read the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status
4208 * into account. Return 0 in case of success, else an error code.
4210 * This function is to be called from contexts that can sleep.
4212 int gpiod_get_array_value_cansleep(unsigned int array_size,
4213 struct gpio_desc **desc_array,
4214 struct gpio_array *array_info,
4215 unsigned long *value_bitmap)
4217 might_sleep_if(extra_checks);
4220 return gpiod_get_array_value_complex(false, true, array_size,
4221 desc_array, array_info,
4224 EXPORT_SYMBOL_GPL(gpiod_get_array_value_cansleep);
4227 * gpiod_set_raw_value_cansleep() - assign a gpio's raw value
4228 * @desc: gpio whose value will be assigned
4229 * @value: value to assign
4231 * Set the raw value of the GPIO, i.e. the value of its physical line without
4232 * regard for its ACTIVE_LOW status.
4234 * This function is to be called from contexts that can sleep.
4236 void gpiod_set_raw_value_cansleep(struct gpio_desc *desc, int value)
4238 might_sleep_if(extra_checks);
4239 VALIDATE_DESC_VOID(desc);
4240 gpiod_set_raw_value_commit(desc, value);
4242 EXPORT_SYMBOL_GPL(gpiod_set_raw_value_cansleep);
4245 * gpiod_set_value_cansleep() - assign a gpio's value
4246 * @desc: gpio whose value will be assigned
4247 * @value: value to assign
4249 * Set the logical value of the GPIO, i.e. taking its ACTIVE_LOW status into
4252 * This function is to be called from contexts that can sleep.
4254 void gpiod_set_value_cansleep(struct gpio_desc *desc, int value)
4256 might_sleep_if(extra_checks);
4257 VALIDATE_DESC_VOID(desc);
4258 gpiod_set_value_nocheck(desc, value);
4260 EXPORT_SYMBOL_GPL(gpiod_set_value_cansleep);
4263 * gpiod_set_raw_array_value_cansleep() - assign values to an array of GPIOs
4264 * @array_size: number of elements in the descriptor array / value bitmap
4265 * @desc_array: array of GPIO descriptors whose values will be assigned
4266 * @array_info: information on applicability of fast bitmap processing path
4267 * @value_bitmap: bitmap of values to assign
4269 * Set the raw values of the GPIOs, i.e. the values of the physical lines
4270 * without regard for their ACTIVE_LOW status.
4272 * This function is to be called from contexts that can sleep.
4274 int gpiod_set_raw_array_value_cansleep(unsigned int array_size,
4275 struct gpio_desc **desc_array,
4276 struct gpio_array *array_info,
4277 unsigned long *value_bitmap)
4279 might_sleep_if(extra_checks);
4282 return gpiod_set_array_value_complex(true, true, array_size, desc_array,
4283 array_info, value_bitmap);
4285 EXPORT_SYMBOL_GPL(gpiod_set_raw_array_value_cansleep);
4288 * gpiod_add_lookup_tables() - register GPIO device consumers
4289 * @tables: list of tables of consumers to register
4290 * @n: number of tables in the list
4292 void gpiod_add_lookup_tables(struct gpiod_lookup_table **tables, size_t n)
4296 mutex_lock(&gpio_lookup_lock);
4298 for (i = 0; i < n; i++)
4299 list_add_tail(&tables[i]->list, &gpio_lookup_list);
4301 mutex_unlock(&gpio_lookup_lock);
4305 * gpiod_set_array_value_cansleep() - assign values to an array of GPIOs
4306 * @array_size: number of elements in the descriptor array / value bitmap
4307 * @desc_array: array of GPIO descriptors whose values will be assigned
4308 * @array_info: information on applicability of fast bitmap processing path
4309 * @value_bitmap: bitmap of values to assign
4311 * Set the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status
4314 * This function is to be called from contexts that can sleep.
4316 int gpiod_set_array_value_cansleep(unsigned int array_size,
4317 struct gpio_desc **desc_array,
4318 struct gpio_array *array_info,
4319 unsigned long *value_bitmap)
4321 might_sleep_if(extra_checks);
4324 return gpiod_set_array_value_complex(false, true, array_size,
4325 desc_array, array_info,
4328 EXPORT_SYMBOL_GPL(gpiod_set_array_value_cansleep);
4331 * gpiod_add_lookup_table() - register GPIO device consumers
4332 * @table: table of consumers to register
4334 void gpiod_add_lookup_table(struct gpiod_lookup_table *table)
4336 mutex_lock(&gpio_lookup_lock);
4338 list_add_tail(&table->list, &gpio_lookup_list);
4340 mutex_unlock(&gpio_lookup_lock);
4342 EXPORT_SYMBOL_GPL(gpiod_add_lookup_table);
4345 * gpiod_remove_lookup_table() - unregister GPIO device consumers
4346 * @table: table of consumers to unregister
4348 void gpiod_remove_lookup_table(struct gpiod_lookup_table *table)
4350 mutex_lock(&gpio_lookup_lock);
4352 list_del(&table->list);
4354 mutex_unlock(&gpio_lookup_lock);
4356 EXPORT_SYMBOL_GPL(gpiod_remove_lookup_table);
4359 * gpiod_add_hogs() - register a set of GPIO hogs from machine code
4360 * @hogs: table of gpio hog entries with a zeroed sentinel at the end
4362 void gpiod_add_hogs(struct gpiod_hog *hogs)
4364 struct gpio_chip *chip;
4365 struct gpiod_hog *hog;
4367 mutex_lock(&gpio_machine_hogs_mutex);
4369 for (hog = &hogs[0]; hog->chip_label; hog++) {
4370 list_add_tail(&hog->list, &gpio_machine_hogs);
4373 * The chip may have been registered earlier, so check if it
4374 * exists and, if so, try to hog the line now.
4376 chip = find_chip_by_name(hog->chip_label);
4378 gpiochip_machine_hog(chip, hog);
4381 mutex_unlock(&gpio_machine_hogs_mutex);
4383 EXPORT_SYMBOL_GPL(gpiod_add_hogs);
4385 static struct gpiod_lookup_table *gpiod_find_lookup_table(struct device *dev)
4387 const char *dev_id = dev ? dev_name(dev) : NULL;
4388 struct gpiod_lookup_table *table;
4390 mutex_lock(&gpio_lookup_lock);
4392 list_for_each_entry(table, &gpio_lookup_list, list) {
4393 if (table->dev_id && dev_id) {
4395 * Valid strings on both ends, must be identical to have
4398 if (!strcmp(table->dev_id, dev_id))
4402 * One of the pointers is NULL, so both must be to have
4405 if (dev_id == table->dev_id)
4412 mutex_unlock(&gpio_lookup_lock);
4416 static struct gpio_desc *gpiod_find(struct device *dev, const char *con_id,
4417 unsigned int idx, unsigned long *flags)
4419 struct gpio_desc *desc = ERR_PTR(-ENOENT);
4420 struct gpiod_lookup_table *table;
4421 struct gpiod_lookup *p;
4423 table = gpiod_find_lookup_table(dev);
4427 for (p = &table->table[0]; p->chip_label; p++) {
4428 struct gpio_chip *chip;
4430 /* idx must always match exactly */
4434 /* If the lookup entry has a con_id, require exact match */
4435 if (p->con_id && (!con_id || strcmp(p->con_id, con_id)))
4438 chip = find_chip_by_name(p->chip_label);
4442 * As the lookup table indicates a chip with
4443 * p->chip_label should exist, assume it may
4444 * still appear later and let the interested
4445 * consumer be probed again or let the Deferred
4446 * Probe infrastructure handle the error.
4448 dev_warn(dev, "cannot find GPIO chip %s, deferring\n",
4450 return ERR_PTR(-EPROBE_DEFER);
4453 if (chip->ngpio <= p->chip_hwnum) {
4455 "requested GPIO %u (%u) is out of range [0..%u] for chip %s\n",
4456 idx, p->chip_hwnum, chip->ngpio - 1,
4458 return ERR_PTR(-EINVAL);
4461 desc = gpiochip_get_desc(chip, p->chip_hwnum);
4470 static int platform_gpio_count(struct device *dev, const char *con_id)
4472 struct gpiod_lookup_table *table;
4473 struct gpiod_lookup *p;
4474 unsigned int count = 0;
4476 table = gpiod_find_lookup_table(dev);
4480 for (p = &table->table[0]; p->chip_label; p++) {
4481 if ((con_id && p->con_id && !strcmp(con_id, p->con_id)) ||
4482 (!con_id && !p->con_id))
4492 * fwnode_gpiod_get_index - obtain a GPIO from firmware node
4493 * @fwnode: handle of the firmware node
4494 * @con_id: function within the GPIO consumer
4495 * @index: index of the GPIO to obtain for the consumer
4496 * @flags: GPIO initialization flags
4497 * @label: label to attach to the requested GPIO
4499 * This function can be used for drivers that get their configuration
4500 * from opaque firmware.
4502 * The function properly finds the corresponding GPIO using whatever is the
4503 * underlying firmware interface and then makes sure that the GPIO
4504 * descriptor is requested before it is returned to the caller.
4507 * On successful request the GPIO pin is configured in accordance with
4510 * In case of error an ERR_PTR() is returned.
4512 struct gpio_desc *fwnode_gpiod_get_index(struct fwnode_handle *fwnode,
4513 const char *con_id, int index,
4514 enum gpiod_flags flags,
4517 struct gpio_desc *desc;
4518 char prop_name[32]; /* 32 is max size of property name */
4521 for (i = 0; i < ARRAY_SIZE(gpio_suffixes); i++) {
4523 snprintf(prop_name, sizeof(prop_name), "%s-%s",
4524 con_id, gpio_suffixes[i]);
4526 snprintf(prop_name, sizeof(prop_name), "%s",
4529 desc = fwnode_get_named_gpiod(fwnode, prop_name, index, flags,
4531 if (!IS_ERR(desc) || (PTR_ERR(desc) != -ENOENT))
4537 EXPORT_SYMBOL_GPL(fwnode_gpiod_get_index);
4540 * gpiod_count - return the number of GPIOs associated with a device / function
4541 * or -ENOENT if no GPIO has been assigned to the requested function
4542 * @dev: GPIO consumer, can be NULL for system-global GPIOs
4543 * @con_id: function within the GPIO consumer
4545 int gpiod_count(struct device *dev, const char *con_id)
4547 int count = -ENOENT;
4549 if (IS_ENABLED(CONFIG_OF) && dev && dev->of_node)
4550 count = of_gpio_get_count(dev, con_id);
4551 else if (IS_ENABLED(CONFIG_ACPI) && dev && ACPI_HANDLE(dev))
4552 count = acpi_gpio_count(dev, con_id);
4555 count = platform_gpio_count(dev, con_id);
4559 EXPORT_SYMBOL_GPL(gpiod_count);
4562 * gpiod_get - obtain a GPIO for a given GPIO function
4563 * @dev: GPIO consumer, can be NULL for system-global GPIOs
4564 * @con_id: function within the GPIO consumer
4565 * @flags: optional GPIO initialization flags
4567 * Return the GPIO descriptor corresponding to the function con_id of device
4568 * dev, -ENOENT if no GPIO has been assigned to the requested function, or
4569 * another IS_ERR() code if an error occurred while trying to acquire the GPIO.
4571 struct gpio_desc *__must_check gpiod_get(struct device *dev, const char *con_id,
4572 enum gpiod_flags flags)
4574 return gpiod_get_index(dev, con_id, 0, flags);
4576 EXPORT_SYMBOL_GPL(gpiod_get);
4579 * gpiod_get_optional - obtain an optional GPIO for a given GPIO function
4580 * @dev: GPIO consumer, can be NULL for system-global GPIOs
4581 * @con_id: function within the GPIO consumer
4582 * @flags: optional GPIO initialization flags
4584 * This is equivalent to gpiod_get(), except that when no GPIO was assigned to
4585 * the requested function it will return NULL. This is convenient for drivers
4586 * that need to handle optional GPIOs.
4588 struct gpio_desc *__must_check gpiod_get_optional(struct device *dev,
4590 enum gpiod_flags flags)
4592 return gpiod_get_index_optional(dev, con_id, 0, flags);
4594 EXPORT_SYMBOL_GPL(gpiod_get_optional);
4598 * gpiod_configure_flags - helper function to configure a given GPIO
4599 * @desc: gpio whose value will be assigned
4600 * @con_id: function within the GPIO consumer
4601 * @lflags: bitmask of gpio_lookup_flags GPIO_* values - returned from
4602 * of_find_gpio() or of_get_gpio_hog()
4603 * @dflags: gpiod_flags - optional GPIO initialization flags
4605 * Return 0 on success, -ENOENT if no GPIO has been assigned to the
4606 * requested function and/or index, or another IS_ERR() code if an error
4607 * occurred while trying to acquire the GPIO.
4609 int gpiod_configure_flags(struct gpio_desc *desc, const char *con_id,
4610 unsigned long lflags, enum gpiod_flags dflags)
4614 if (lflags & GPIO_ACTIVE_LOW)
4615 set_bit(FLAG_ACTIVE_LOW, &desc->flags);
4617 if (lflags & GPIO_OPEN_DRAIN)
4618 set_bit(FLAG_OPEN_DRAIN, &desc->flags);
4619 else if (dflags & GPIOD_FLAGS_BIT_OPEN_DRAIN) {
4621 * This enforces open drain mode from the consumer side.
4622 * This is necessary for some busses like I2C, but the lookup
4623 * should *REALLY* have specified them as open drain in the
4624 * first place, so print a little warning here.
4626 set_bit(FLAG_OPEN_DRAIN, &desc->flags);
4628 "enforced open drain please flag it properly in DT/ACPI DSDT/board file\n");
4631 if (lflags & GPIO_OPEN_SOURCE)
4632 set_bit(FLAG_OPEN_SOURCE, &desc->flags);
4634 if ((lflags & GPIO_PULL_UP) && (lflags & GPIO_PULL_DOWN)) {
4636 "both pull-up and pull-down enabled, invalid configuration\n");
4640 if (lflags & GPIO_PULL_UP)
4641 set_bit(FLAG_PULL_UP, &desc->flags);
4642 else if (lflags & GPIO_PULL_DOWN)
4643 set_bit(FLAG_PULL_DOWN, &desc->flags);
4645 ret = gpiod_set_transitory(desc, (lflags & GPIO_TRANSITORY));
4649 /* No particular flag request, return here... */
4650 if (!(dflags & GPIOD_FLAGS_BIT_DIR_SET)) {
4651 pr_debug("no flags found for %s\n", con_id);
4656 if (dflags & GPIOD_FLAGS_BIT_DIR_OUT)
4657 ret = gpiod_direction_output(desc,
4658 !!(dflags & GPIOD_FLAGS_BIT_DIR_VAL));
4660 ret = gpiod_direction_input(desc);
4666 * gpiod_get_index - obtain a GPIO from a multi-index GPIO function
4667 * @dev: GPIO consumer, can be NULL for system-global GPIOs
4668 * @con_id: function within the GPIO consumer
4669 * @idx: index of the GPIO to obtain in the consumer
4670 * @flags: optional GPIO initialization flags
4672 * This variant of gpiod_get() allows to access GPIOs other than the first
4673 * defined one for functions that define several GPIOs.
4675 * Return a valid GPIO descriptor, -ENOENT if no GPIO has been assigned to the
4676 * requested function and/or index, or another IS_ERR() code if an error
4677 * occurred while trying to acquire the GPIO.
4679 struct gpio_desc *__must_check gpiod_get_index(struct device *dev,
4682 enum gpiod_flags flags)
4684 unsigned long lookupflags = GPIO_LOOKUP_FLAGS_DEFAULT;
4685 struct gpio_desc *desc = NULL;
4687 /* Maybe we have a device name, maybe not */
4688 const char *devname = dev ? dev_name(dev) : "?";
4690 dev_dbg(dev, "GPIO lookup for consumer %s\n", con_id);
4693 /* Using device tree? */
4694 if (IS_ENABLED(CONFIG_OF) && dev->of_node) {
4695 dev_dbg(dev, "using device tree for GPIO lookup\n");
4696 desc = of_find_gpio(dev, con_id, idx, &lookupflags);
4697 } else if (ACPI_COMPANION(dev)) {
4698 dev_dbg(dev, "using ACPI for GPIO lookup\n");
4699 desc = acpi_find_gpio(dev, con_id, idx, &flags, &lookupflags);
4704 * Either we are not using DT or ACPI, or their lookup did not return
4705 * a result. In that case, use platform lookup as a fallback.
4707 if (!desc || desc == ERR_PTR(-ENOENT)) {
4708 dev_dbg(dev, "using lookup tables for GPIO lookup\n");
4709 desc = gpiod_find(dev, con_id, idx, &lookupflags);
4713 dev_dbg(dev, "No GPIO consumer %s found\n", con_id);
4718 * If a connection label was passed use that, else attempt to use
4719 * the device name as label
4721 ret = gpiod_request(desc, con_id ? con_id : devname);
4723 if (ret == -EBUSY && flags & GPIOD_FLAGS_BIT_NONEXCLUSIVE) {
4725 * This happens when there are several consumers for
4726 * the same GPIO line: we just return here without
4727 * further initialization. It is a bit if a hack.
4728 * This is necessary to support fixed regulators.
4730 * FIXME: Make this more sane and safe.
4732 dev_info(dev, "nonexclusive access to GPIO for %s\n",
4733 con_id ? con_id : devname);
4736 return ERR_PTR(ret);
4740 ret = gpiod_configure_flags(desc, con_id, lookupflags, flags);
4742 dev_dbg(dev, "setup of GPIO %s failed\n", con_id);
4744 return ERR_PTR(ret);
4749 EXPORT_SYMBOL_GPL(gpiod_get_index);
4752 * fwnode_get_named_gpiod - obtain a GPIO from firmware node
4753 * @fwnode: handle of the firmware node
4754 * @propname: name of the firmware property representing the GPIO
4755 * @index: index of the GPIO to obtain for the consumer
4756 * @dflags: GPIO initialization flags
4757 * @label: label to attach to the requested GPIO
4759 * This function can be used for drivers that get their configuration
4760 * from opaque firmware.
4762 * The function properly finds the corresponding GPIO using whatever is the
4763 * underlying firmware interface and then makes sure that the GPIO
4764 * descriptor is requested before it is returned to the caller.
4767 * On successful request the GPIO pin is configured in accordance with
4770 * In case of error an ERR_PTR() is returned.
4772 struct gpio_desc *fwnode_get_named_gpiod(struct fwnode_handle *fwnode,
4773 const char *propname, int index,
4774 enum gpiod_flags dflags,
4777 unsigned long lflags = GPIO_LOOKUP_FLAGS_DEFAULT;
4778 struct gpio_desc *desc = ERR_PTR(-ENODEV);
4782 return ERR_PTR(-EINVAL);
4784 if (is_of_node(fwnode)) {
4785 desc = gpiod_get_from_of_node(to_of_node(fwnode),
4790 } else if (is_acpi_node(fwnode)) {
4791 struct acpi_gpio_info info;
4793 desc = acpi_node_get_gpiod(fwnode, propname, index, &info);
4797 acpi_gpio_update_gpiod_flags(&dflags, &info);
4798 acpi_gpio_update_gpiod_lookup_flags(&lflags, &info);
4801 /* Currently only ACPI takes this path */
4802 ret = gpiod_request(desc, label);
4804 return ERR_PTR(ret);
4806 ret = gpiod_configure_flags(desc, propname, lflags, dflags);
4809 return ERR_PTR(ret);
4814 EXPORT_SYMBOL_GPL(fwnode_get_named_gpiod);
4817 * gpiod_get_index_optional - obtain an optional GPIO from a multi-index GPIO
4819 * @dev: GPIO consumer, can be NULL for system-global GPIOs
4820 * @con_id: function within the GPIO consumer
4821 * @index: index of the GPIO to obtain in the consumer
4822 * @flags: optional GPIO initialization flags
4824 * This is equivalent to gpiod_get_index(), except that when no GPIO with the
4825 * specified index was assigned to the requested function it will return NULL.
4826 * This is convenient for drivers that need to handle optional GPIOs.
4828 struct gpio_desc *__must_check gpiod_get_index_optional(struct device *dev,
4831 enum gpiod_flags flags)
4833 struct gpio_desc *desc;
4835 desc = gpiod_get_index(dev, con_id, index, flags);
4837 if (PTR_ERR(desc) == -ENOENT)
4843 EXPORT_SYMBOL_GPL(gpiod_get_index_optional);
4846 * gpiod_hog - Hog the specified GPIO desc given the provided flags
4847 * @desc: gpio whose value will be assigned
4848 * @name: gpio line name
4849 * @lflags: bitmask of gpio_lookup_flags GPIO_* values - returned from
4850 * of_find_gpio() or of_get_gpio_hog()
4851 * @dflags: gpiod_flags - optional GPIO initialization flags
4853 int gpiod_hog(struct gpio_desc *desc, const char *name,
4854 unsigned long lflags, enum gpiod_flags dflags)
4856 struct gpio_chip *chip;
4857 struct gpio_desc *local_desc;
4861 chip = gpiod_to_chip(desc);
4862 hwnum = gpio_chip_hwgpio(desc);
4864 local_desc = gpiochip_request_own_desc(chip, hwnum, name,
4866 if (IS_ERR(local_desc)) {
4867 ret = PTR_ERR(local_desc);
4868 pr_err("requesting hog GPIO %s (chip %s, offset %d) failed, %d\n",
4869 name, chip->label, hwnum, ret);
4873 /* Mark GPIO as hogged so it can be identified and removed later */
4874 set_bit(FLAG_IS_HOGGED, &desc->flags);
4876 pr_info("GPIO line %d (%s) hogged as %s%s\n",
4877 desc_to_gpio(desc), name,
4878 (dflags & GPIOD_FLAGS_BIT_DIR_OUT) ? "output" : "input",
4879 (dflags & GPIOD_FLAGS_BIT_DIR_OUT) ?
4880 (dflags & GPIOD_FLAGS_BIT_DIR_VAL) ? "/high" : "/low" : "");
4886 * gpiochip_free_hogs - Scan gpio-controller chip and release GPIO hog
4887 * @chip: gpio chip to act on
4889 static void gpiochip_free_hogs(struct gpio_chip *chip)
4893 for (id = 0; id < chip->ngpio; id++) {
4894 if (test_bit(FLAG_IS_HOGGED, &chip->gpiodev->descs[id].flags))
4895 gpiochip_free_own_desc(&chip->gpiodev->descs[id]);
4900 * gpiod_get_array - obtain multiple GPIOs from a multi-index GPIO function
4901 * @dev: GPIO consumer, can be NULL for system-global GPIOs
4902 * @con_id: function within the GPIO consumer
4903 * @flags: optional GPIO initialization flags
4905 * This function acquires all the GPIOs defined under a given function.
4907 * Return a struct gpio_descs containing an array of descriptors, -ENOENT if
4908 * no GPIO has been assigned to the requested function, or another IS_ERR()
4909 * code if an error occurred while trying to acquire the GPIOs.
4911 struct gpio_descs *__must_check gpiod_get_array(struct device *dev,
4913 enum gpiod_flags flags)
4915 struct gpio_desc *desc;
4916 struct gpio_descs *descs;
4917 struct gpio_array *array_info = NULL;
4918 struct gpio_chip *chip;
4919 int count, bitmap_size;
4921 count = gpiod_count(dev, con_id);
4923 return ERR_PTR(count);
4925 descs = kzalloc(struct_size(descs, desc, count), GFP_KERNEL);
4927 return ERR_PTR(-ENOMEM);
4929 for (descs->ndescs = 0; descs->ndescs < count; ) {
4930 desc = gpiod_get_index(dev, con_id, descs->ndescs, flags);
4932 gpiod_put_array(descs);
4933 return ERR_CAST(desc);
4936 descs->desc[descs->ndescs] = desc;
4938 chip = gpiod_to_chip(desc);
4940 * If pin hardware number of array member 0 is also 0, select
4941 * its chip as a candidate for fast bitmap processing path.
4943 if (descs->ndescs == 0 && gpio_chip_hwgpio(desc) == 0) {
4944 struct gpio_descs *array;
4946 bitmap_size = BITS_TO_LONGS(chip->ngpio > count ?
4947 chip->ngpio : count);
4949 array = kzalloc(struct_size(descs, desc, count) +
4950 struct_size(array_info, invert_mask,
4951 3 * bitmap_size), GFP_KERNEL);
4953 gpiod_put_array(descs);
4954 return ERR_PTR(-ENOMEM);
4957 memcpy(array, descs,
4958 struct_size(descs, desc, descs->ndescs + 1));
4962 array_info = (void *)(descs->desc + count);
4963 array_info->get_mask = array_info->invert_mask +
4965 array_info->set_mask = array_info->get_mask +
4968 array_info->desc = descs->desc;
4969 array_info->size = count;
4970 array_info->chip = chip;
4971 bitmap_set(array_info->get_mask, descs->ndescs,
4972 count - descs->ndescs);
4973 bitmap_set(array_info->set_mask, descs->ndescs,
4974 count - descs->ndescs);
4975 descs->info = array_info;
4977 /* Unmark array members which don't belong to the 'fast' chip */
4978 if (array_info && array_info->chip != chip) {
4979 __clear_bit(descs->ndescs, array_info->get_mask);
4980 __clear_bit(descs->ndescs, array_info->set_mask);
4983 * Detect array members which belong to the 'fast' chip
4984 * but their pins are not in hardware order.
4986 else if (array_info &&
4987 gpio_chip_hwgpio(desc) != descs->ndescs) {
4989 * Don't use fast path if all array members processed so
4990 * far belong to the same chip as this one but its pin
4991 * hardware number is different from its array index.
4993 if (bitmap_full(array_info->get_mask, descs->ndescs)) {
4996 __clear_bit(descs->ndescs,
4997 array_info->get_mask);
4998 __clear_bit(descs->ndescs,
4999 array_info->set_mask);
5001 } else if (array_info) {
5002 /* Exclude open drain or open source from fast output */
5003 if (gpiochip_line_is_open_drain(chip, descs->ndescs) ||
5004 gpiochip_line_is_open_source(chip, descs->ndescs))
5005 __clear_bit(descs->ndescs,
5006 array_info->set_mask);
5007 /* Identify 'fast' pins which require invertion */
5008 if (gpiod_is_active_low(desc))
5009 __set_bit(descs->ndescs,
5010 array_info->invert_mask);
5017 "GPIO array info: chip=%s, size=%d, get_mask=%lx, set_mask=%lx, invert_mask=%lx\n",
5018 array_info->chip->label, array_info->size,
5019 *array_info->get_mask, *array_info->set_mask,
5020 *array_info->invert_mask);
5023 EXPORT_SYMBOL_GPL(gpiod_get_array);
5026 * gpiod_get_array_optional - obtain multiple GPIOs from a multi-index GPIO
5028 * @dev: GPIO consumer, can be NULL for system-global GPIOs
5029 * @con_id: function within the GPIO consumer
5030 * @flags: optional GPIO initialization flags
5032 * This is equivalent to gpiod_get_array(), except that when no GPIO was
5033 * assigned to the requested function it will return NULL.
5035 struct gpio_descs *__must_check gpiod_get_array_optional(struct device *dev,
5037 enum gpiod_flags flags)
5039 struct gpio_descs *descs;
5041 descs = gpiod_get_array(dev, con_id, flags);
5042 if (PTR_ERR(descs) == -ENOENT)
5047 EXPORT_SYMBOL_GPL(gpiod_get_array_optional);
5050 * gpiod_put - dispose of a GPIO descriptor
5051 * @desc: GPIO descriptor to dispose of
5053 * No descriptor can be used after gpiod_put() has been called on it.
5055 void gpiod_put(struct gpio_desc *desc)
5060 EXPORT_SYMBOL_GPL(gpiod_put);
5063 * gpiod_put_array - dispose of multiple GPIO descriptors
5064 * @descs: struct gpio_descs containing an array of descriptors
5066 void gpiod_put_array(struct gpio_descs *descs)
5070 for (i = 0; i < descs->ndescs; i++)
5071 gpiod_put(descs->desc[i]);
5075 EXPORT_SYMBOL_GPL(gpiod_put_array);
5077 static int __init gpiolib_dev_init(void)
5081 /* Register GPIO sysfs bus */
5082 ret = bus_register(&gpio_bus_type);
5084 pr_err("gpiolib: could not register GPIO bus type\n");
5088 ret = alloc_chrdev_region(&gpio_devt, 0, GPIO_DEV_MAX, GPIOCHIP_NAME);
5090 pr_err("gpiolib: failed to allocate char dev region\n");
5091 bus_unregister(&gpio_bus_type);
5093 gpiolib_initialized = true;
5094 gpiochip_setup_devs();
5098 core_initcall(gpiolib_dev_init);
5100 #ifdef CONFIG_DEBUG_FS
5102 static void gpiolib_dbg_show(struct seq_file *s, struct gpio_device *gdev)
5105 struct gpio_chip *chip = gdev->chip;
5106 unsigned gpio = gdev->base;
5107 struct gpio_desc *gdesc = &gdev->descs[0];
5112 for (i = 0; i < gdev->ngpio; i++, gpio++, gdesc++) {
5113 if (!test_bit(FLAG_REQUESTED, &gdesc->flags)) {
5115 seq_printf(s, " gpio-%-3d (%-20.20s)\n",
5121 gpiod_get_direction(gdesc);
5122 is_out = test_bit(FLAG_IS_OUT, &gdesc->flags);
5123 is_irq = test_bit(FLAG_USED_AS_IRQ, &gdesc->flags);
5124 active_low = test_bit(FLAG_ACTIVE_LOW, &gdesc->flags);
5125 seq_printf(s, " gpio-%-3d (%-20.20s|%-20.20s) %s %s %s%s",
5126 gpio, gdesc->name ? gdesc->name : "", gdesc->label,
5127 is_out ? "out" : "in ",
5128 chip->get ? (chip->get(chip, i) ? "hi" : "lo") : "? ",
5129 is_irq ? "IRQ " : "",
5130 active_low ? "ACTIVE LOW" : "");
5131 seq_printf(s, "\n");
5135 static void *gpiolib_seq_start(struct seq_file *s, loff_t *pos)
5137 unsigned long flags;
5138 struct gpio_device *gdev = NULL;
5139 loff_t index = *pos;
5143 spin_lock_irqsave(&gpio_lock, flags);
5144 list_for_each_entry(gdev, &gpio_devices, list)
5146 spin_unlock_irqrestore(&gpio_lock, flags);
5149 spin_unlock_irqrestore(&gpio_lock, flags);
5154 static void *gpiolib_seq_next(struct seq_file *s, void *v, loff_t *pos)
5156 unsigned long flags;
5157 struct gpio_device *gdev = v;
5160 spin_lock_irqsave(&gpio_lock, flags);
5161 if (list_is_last(&gdev->list, &gpio_devices))
5164 ret = list_entry(gdev->list.next, struct gpio_device, list);
5165 spin_unlock_irqrestore(&gpio_lock, flags);
5173 static void gpiolib_seq_stop(struct seq_file *s, void *v)
5177 static int gpiolib_seq_show(struct seq_file *s, void *v)
5179 struct gpio_device *gdev = v;
5180 struct gpio_chip *chip = gdev->chip;
5181 struct device *parent;
5184 seq_printf(s, "%s%s: (dangling chip)", (char *)s->private,
5185 dev_name(&gdev->dev));
5189 seq_printf(s, "%s%s: GPIOs %d-%d", (char *)s->private,
5190 dev_name(&gdev->dev),
5191 gdev->base, gdev->base + gdev->ngpio - 1);
5192 parent = chip->parent;
5194 seq_printf(s, ", parent: %s/%s",
5195 parent->bus ? parent->bus->name : "no-bus",
5198 seq_printf(s, ", %s", chip->label);
5199 if (chip->can_sleep)
5200 seq_printf(s, ", can sleep");
5201 seq_printf(s, ":\n");
5204 chip->dbg_show(s, chip);
5206 gpiolib_dbg_show(s, gdev);
5211 static const struct seq_operations gpiolib_seq_ops = {
5212 .start = gpiolib_seq_start,
5213 .next = gpiolib_seq_next,
5214 .stop = gpiolib_seq_stop,
5215 .show = gpiolib_seq_show,
5218 static int gpiolib_open(struct inode *inode, struct file *file)
5220 return seq_open(file, &gpiolib_seq_ops);
5223 static const struct file_operations gpiolib_operations = {
5224 .owner = THIS_MODULE,
5225 .open = gpiolib_open,
5227 .llseek = seq_lseek,
5228 .release = seq_release,
5231 static int __init gpiolib_debugfs_init(void)
5233 /* /sys/kernel/debug/gpio */
5234 debugfs_create_file("gpio", S_IFREG | S_IRUGO, NULL, NULL,
5235 &gpiolib_operations);
5238 subsys_initcall(gpiolib_debugfs_init);
5240 #endif /* DEBUG_FS */