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_chained_irqchip() - connects a chained irqchip to a gpiochip
1847 * @gpiochip: the gpiochip to set the irqchip chain to
1848 * @irqchip: the irqchip to chain to the gpiochip
1849 * @parent_irq: the irq number corresponding to the parent IRQ for this
1851 * @parent_handler: the parent interrupt handler for the accumulated IRQ
1852 * coming out of the gpiochip.
1854 void gpiochip_set_chained_irqchip(struct gpio_chip *gpiochip,
1855 struct irq_chip *irqchip,
1856 unsigned int parent_irq,
1857 irq_flow_handler_t parent_handler)
1859 if (gpiochip->irq.threaded) {
1860 chip_err(gpiochip, "tried to chain a threaded gpiochip\n");
1864 gpiochip_set_cascaded_irqchip(gpiochip, parent_irq, parent_handler);
1866 EXPORT_SYMBOL_GPL(gpiochip_set_chained_irqchip);
1869 * gpiochip_set_nested_irqchip() - connects a nested irqchip to a gpiochip
1870 * @gpiochip: the gpiochip to set the irqchip nested handler to
1871 * @irqchip: the irqchip to nest to the gpiochip
1872 * @parent_irq: the irq number corresponding to the parent IRQ for this
1875 void gpiochip_set_nested_irqchip(struct gpio_chip *gpiochip,
1876 struct irq_chip *irqchip,
1877 unsigned int parent_irq)
1879 gpiochip_set_cascaded_irqchip(gpiochip, parent_irq, NULL);
1881 EXPORT_SYMBOL_GPL(gpiochip_set_nested_irqchip);
1883 #ifdef CONFIG_IRQ_DOMAIN_HIERARCHY
1886 * gpiochip_set_hierarchical_irqchip() - connects a hierarchical irqchip
1888 * @gc: the gpiochip to set the irqchip hierarchical handler to
1889 * @irqchip: the irqchip to handle this level of the hierarchy, the interrupt
1890 * will then percolate up to the parent
1892 static void gpiochip_set_hierarchical_irqchip(struct gpio_chip *gc,
1893 struct irq_chip *irqchip)
1895 /* DT will deal with mapping each IRQ as we go along */
1896 if (is_of_node(gc->irq.fwnode))
1900 * This is for legacy and boardfile "irqchip" fwnodes: allocate
1901 * irqs upfront instead of dynamically since we don't have the
1902 * dynamic type of allocation that hardware description languages
1903 * provide. Once all GPIO drivers using board files are gone from
1904 * the kernel we can delete this code, but for a transitional period
1905 * it is necessary to keep this around.
1907 if (is_fwnode_irqchip(gc->irq.fwnode)) {
1911 for (i = 0; i < gc->ngpio; i++) {
1912 struct irq_fwspec fwspec;
1913 unsigned int parent_hwirq;
1914 unsigned int parent_type;
1915 struct gpio_irq_chip *girq = &gc->irq;
1918 * We call the child to parent translation function
1919 * only to check if the child IRQ is valid or not.
1920 * Just pick the rising edge type here as that is what
1921 * we likely need to support.
1923 ret = girq->child_to_parent_hwirq(gc, i,
1924 IRQ_TYPE_EDGE_RISING,
1928 chip_err(gc, "skip set-up on hwirq %d\n",
1933 fwspec.fwnode = gc->irq.fwnode;
1934 /* This is the hwirq for the GPIO line side of things */
1935 fwspec.param[0] = girq->child_offset_to_irq(gc, i);
1936 /* Just pick something */
1937 fwspec.param[1] = IRQ_TYPE_EDGE_RISING;
1938 fwspec.param_count = 2;
1939 ret = __irq_domain_alloc_irqs(gc->irq.domain,
1940 /* just pick something */
1949 "can not allocate irq for GPIO line %d parent hwirq %d in hierarchy domain: %d\n",
1956 chip_err(gc, "%s unknown fwnode type proceed anyway\n", __func__);
1961 static int gpiochip_hierarchy_irq_domain_translate(struct irq_domain *d,
1962 struct irq_fwspec *fwspec,
1963 unsigned long *hwirq,
1966 /* We support standard DT translation */
1967 if (is_of_node(fwspec->fwnode) && fwspec->param_count == 2) {
1968 return irq_domain_translate_twocell(d, fwspec, hwirq, type);
1971 /* This is for board files and others not using DT */
1972 if (is_fwnode_irqchip(fwspec->fwnode)) {
1975 ret = irq_domain_translate_twocell(d, fwspec, hwirq, type);
1978 WARN_ON(*type == IRQ_TYPE_NONE);
1984 static int gpiochip_hierarchy_irq_domain_alloc(struct irq_domain *d,
1986 unsigned int nr_irqs,
1989 struct gpio_chip *gc = d->host_data;
1990 irq_hw_number_t hwirq;
1991 unsigned int type = IRQ_TYPE_NONE;
1992 struct irq_fwspec *fwspec = data;
1994 unsigned int parent_hwirq;
1995 unsigned int parent_type;
1996 struct gpio_irq_chip *girq = &gc->irq;
2000 * The nr_irqs parameter is always one except for PCI multi-MSI
2001 * so this should not happen.
2003 WARN_ON(nr_irqs != 1);
2005 ret = gc->irq.child_irq_domain_ops.translate(d, fwspec, &hwirq, &type);
2009 chip_dbg(gc, "allocate IRQ %d, hwirq %lu\n", irq, hwirq);
2011 ret = girq->child_to_parent_hwirq(gc, hwirq, type,
2012 &parent_hwirq, &parent_type);
2014 chip_err(gc, "can't look up hwirq %lu\n", hwirq);
2017 chip_dbg(gc, "found parent hwirq %u\n", parent_hwirq);
2020 * We set handle_bad_irq because the .set_type() should
2021 * always be invoked and set the right type of handler.
2023 irq_domain_set_info(d,
2032 /* This parent only handles asserted level IRQs */
2033 parent_arg = girq->populate_parent_alloc_arg(gc, parent_hwirq, parent_type);
2037 chip_dbg(gc, "alloc_irqs_parent for %d parent hwirq %d\n",
2039 irq_set_lockdep_class(irq, gc->irq.lock_key, gc->irq.request_key);
2040 ret = irq_domain_alloc_irqs_parent(d, irq, 1, parent_arg);
2042 * If the parent irqdomain is msi, the interrupts have already
2043 * been allocated, so the EEXIST is good.
2045 if (irq_domain_is_msi(d->parent) && (ret == -EEXIST))
2049 "failed to allocate parent hwirq %d for hwirq %lu\n",
2050 parent_hwirq, hwirq);
2056 static unsigned int gpiochip_child_offset_to_irq_noop(struct gpio_chip *chip,
2057 unsigned int offset)
2062 static void gpiochip_hierarchy_setup_domain_ops(struct irq_domain_ops *ops)
2064 ops->activate = gpiochip_irq_domain_activate;
2065 ops->deactivate = gpiochip_irq_domain_deactivate;
2066 ops->alloc = gpiochip_hierarchy_irq_domain_alloc;
2067 ops->free = irq_domain_free_irqs_common;
2070 * We only allow overriding the translate() function for
2071 * hierarchical chips, and this should only be done if the user
2072 * really need something other than 1:1 translation.
2074 if (!ops->translate)
2075 ops->translate = gpiochip_hierarchy_irq_domain_translate;
2078 static int gpiochip_hierarchy_add_domain(struct gpio_chip *gc)
2080 if (!gc->irq.child_to_parent_hwirq ||
2082 chip_err(gc, "missing irqdomain vital data\n");
2086 if (!gc->irq.child_offset_to_irq)
2087 gc->irq.child_offset_to_irq = gpiochip_child_offset_to_irq_noop;
2089 if (!gc->irq.populate_parent_alloc_arg)
2090 gc->irq.populate_parent_alloc_arg =
2091 gpiochip_populate_parent_fwspec_twocell;
2093 gpiochip_hierarchy_setup_domain_ops(&gc->irq.child_irq_domain_ops);
2095 gc->irq.domain = irq_domain_create_hierarchy(
2096 gc->irq.parent_domain,
2100 &gc->irq.child_irq_domain_ops,
2103 if (!gc->irq.domain)
2106 gpiochip_set_hierarchical_irqchip(gc, gc->irq.chip);
2111 static bool gpiochip_hierarchy_is_hierarchical(struct gpio_chip *gc)
2113 return !!gc->irq.parent_domain;
2116 void *gpiochip_populate_parent_fwspec_twocell(struct gpio_chip *chip,
2117 unsigned int parent_hwirq,
2118 unsigned int parent_type)
2120 struct irq_fwspec *fwspec;
2122 fwspec = kmalloc(sizeof(*fwspec), GFP_KERNEL);
2126 fwspec->fwnode = chip->irq.parent_domain->fwnode;
2127 fwspec->param_count = 2;
2128 fwspec->param[0] = parent_hwirq;
2129 fwspec->param[1] = parent_type;
2133 EXPORT_SYMBOL_GPL(gpiochip_populate_parent_fwspec_twocell);
2135 void *gpiochip_populate_parent_fwspec_fourcell(struct gpio_chip *chip,
2136 unsigned int parent_hwirq,
2137 unsigned int parent_type)
2139 struct irq_fwspec *fwspec;
2141 fwspec = kmalloc(sizeof(*fwspec), GFP_KERNEL);
2145 fwspec->fwnode = chip->irq.parent_domain->fwnode;
2146 fwspec->param_count = 4;
2147 fwspec->param[0] = 0;
2148 fwspec->param[1] = parent_hwirq;
2149 fwspec->param[2] = 0;
2150 fwspec->param[3] = parent_type;
2154 EXPORT_SYMBOL_GPL(gpiochip_populate_parent_fwspec_fourcell);
2158 static int gpiochip_hierarchy_add_domain(struct gpio_chip *gc)
2163 static bool gpiochip_hierarchy_is_hierarchical(struct gpio_chip *gc)
2168 #endif /* CONFIG_IRQ_DOMAIN_HIERARCHY */
2171 * gpiochip_irq_map() - maps an IRQ into a GPIO irqchip
2172 * @d: the irqdomain used by this irqchip
2173 * @irq: the global irq number used by this GPIO irqchip irq
2174 * @hwirq: the local IRQ/GPIO line offset on this gpiochip
2176 * This function will set up the mapping for a certain IRQ line on a
2177 * gpiochip by assigning the gpiochip as chip data, and using the irqchip
2178 * stored inside the gpiochip.
2180 int gpiochip_irq_map(struct irq_domain *d, unsigned int irq,
2181 irq_hw_number_t hwirq)
2183 struct gpio_chip *chip = d->host_data;
2186 if (!gpiochip_irqchip_irq_valid(chip, hwirq))
2189 irq_set_chip_data(irq, chip);
2191 * This lock class tells lockdep that GPIO irqs are in a different
2192 * category than their parents, so it won't report false recursion.
2194 irq_set_lockdep_class(irq, chip->irq.lock_key, chip->irq.request_key);
2195 irq_set_chip_and_handler(irq, chip->irq.chip, chip->irq.handler);
2196 /* Chips that use nested thread handlers have them marked */
2197 if (chip->irq.threaded)
2198 irq_set_nested_thread(irq, 1);
2199 irq_set_noprobe(irq);
2201 if (chip->irq.num_parents == 1)
2202 ret = irq_set_parent(irq, chip->irq.parents[0]);
2203 else if (chip->irq.map)
2204 ret = irq_set_parent(irq, chip->irq.map[hwirq]);
2210 * No set-up of the hardware will happen if IRQ_TYPE_NONE
2211 * is passed as default type.
2213 if (chip->irq.default_type != IRQ_TYPE_NONE)
2214 irq_set_irq_type(irq, chip->irq.default_type);
2218 EXPORT_SYMBOL_GPL(gpiochip_irq_map);
2220 void gpiochip_irq_unmap(struct irq_domain *d, unsigned int irq)
2222 struct gpio_chip *chip = d->host_data;
2224 if (chip->irq.threaded)
2225 irq_set_nested_thread(irq, 0);
2226 irq_set_chip_and_handler(irq, NULL, NULL);
2227 irq_set_chip_data(irq, NULL);
2229 EXPORT_SYMBOL_GPL(gpiochip_irq_unmap);
2231 static const struct irq_domain_ops gpiochip_domain_ops = {
2232 .map = gpiochip_irq_map,
2233 .unmap = gpiochip_irq_unmap,
2234 /* Virtually all GPIO irqchips are twocell:ed */
2235 .xlate = irq_domain_xlate_twocell,
2239 * TODO: move these activate/deactivate in under the hierarchicial
2240 * irqchip implementation as static once SPMI and SSBI (all external
2241 * users) are phased over.
2244 * gpiochip_irq_domain_activate() - Lock a GPIO to be used as an IRQ
2245 * @domain: The IRQ domain used by this IRQ chip
2246 * @data: Outermost irq_data associated with the IRQ
2247 * @reserve: If set, only reserve an interrupt vector instead of assigning one
2249 * This function is a wrapper that calls gpiochip_lock_as_irq() and is to be
2250 * used as the activate function for the &struct irq_domain_ops. The host_data
2251 * for the IRQ domain must be the &struct gpio_chip.
2253 int gpiochip_irq_domain_activate(struct irq_domain *domain,
2254 struct irq_data *data, bool reserve)
2256 struct gpio_chip *chip = domain->host_data;
2258 return gpiochip_lock_as_irq(chip, data->hwirq);
2260 EXPORT_SYMBOL_GPL(gpiochip_irq_domain_activate);
2263 * gpiochip_irq_domain_deactivate() - Unlock a GPIO used as an IRQ
2264 * @domain: The IRQ domain used by this IRQ chip
2265 * @data: Outermost irq_data associated with the IRQ
2267 * This function is a wrapper that will call gpiochip_unlock_as_irq() and is to
2268 * be used as the deactivate function for the &struct irq_domain_ops. The
2269 * host_data for the IRQ domain must be the &struct gpio_chip.
2271 void gpiochip_irq_domain_deactivate(struct irq_domain *domain,
2272 struct irq_data *data)
2274 struct gpio_chip *chip = domain->host_data;
2276 return gpiochip_unlock_as_irq(chip, data->hwirq);
2278 EXPORT_SYMBOL_GPL(gpiochip_irq_domain_deactivate);
2280 static int gpiochip_to_irq(struct gpio_chip *chip, unsigned offset)
2282 struct irq_domain *domain = chip->irq.domain;
2284 if (!gpiochip_irqchip_irq_valid(chip, offset))
2287 #ifdef CONFIG_IRQ_DOMAIN_HIERARCHY
2288 if (irq_domain_is_hierarchy(domain)) {
2289 struct irq_fwspec spec;
2291 spec.fwnode = domain->fwnode;
2292 spec.param_count = 2;
2293 spec.param[0] = chip->irq.child_offset_to_irq(chip, offset);
2294 spec.param[1] = IRQ_TYPE_NONE;
2296 return irq_create_fwspec_mapping(&spec);
2300 return irq_create_mapping(domain, offset);
2303 static int gpiochip_irq_reqres(struct irq_data *d)
2305 struct gpio_chip *chip = irq_data_get_irq_chip_data(d);
2307 return gpiochip_reqres_irq(chip, d->hwirq);
2310 static void gpiochip_irq_relres(struct irq_data *d)
2312 struct gpio_chip *chip = irq_data_get_irq_chip_data(d);
2314 gpiochip_relres_irq(chip, d->hwirq);
2317 static void gpiochip_irq_enable(struct irq_data *d)
2319 struct gpio_chip *chip = irq_data_get_irq_chip_data(d);
2321 gpiochip_enable_irq(chip, d->hwirq);
2322 if (chip->irq.irq_enable)
2323 chip->irq.irq_enable(d);
2325 chip->irq.chip->irq_unmask(d);
2328 static void gpiochip_irq_disable(struct irq_data *d)
2330 struct gpio_chip *chip = irq_data_get_irq_chip_data(d);
2332 if (chip->irq.irq_disable)
2333 chip->irq.irq_disable(d);
2335 chip->irq.chip->irq_mask(d);
2336 gpiochip_disable_irq(chip, d->hwirq);
2339 static void gpiochip_set_irq_hooks(struct gpio_chip *gpiochip)
2341 struct irq_chip *irqchip = gpiochip->irq.chip;
2343 if (!irqchip->irq_request_resources &&
2344 !irqchip->irq_release_resources) {
2345 irqchip->irq_request_resources = gpiochip_irq_reqres;
2346 irqchip->irq_release_resources = gpiochip_irq_relres;
2348 if (WARN_ON(gpiochip->irq.irq_enable))
2350 /* Check if the irqchip already has this hook... */
2351 if (irqchip->irq_enable == gpiochip_irq_enable) {
2353 * ...and if so, give a gentle warning that this is bad
2357 "detected irqchip that is shared with multiple gpiochips: please fix the driver.\n");
2360 gpiochip->irq.irq_enable = irqchip->irq_enable;
2361 gpiochip->irq.irq_disable = irqchip->irq_disable;
2362 irqchip->irq_enable = gpiochip_irq_enable;
2363 irqchip->irq_disable = gpiochip_irq_disable;
2367 * gpiochip_add_irqchip() - adds an IRQ chip to a GPIO chip
2368 * @gpiochip: the GPIO chip to add the IRQ chip to
2369 * @lock_key: lockdep class for IRQ lock
2370 * @request_key: lockdep class for IRQ request
2372 static int gpiochip_add_irqchip(struct gpio_chip *gpiochip,
2373 struct lock_class_key *lock_key,
2374 struct lock_class_key *request_key)
2376 struct irq_chip *irqchip = gpiochip->irq.chip;
2377 const struct irq_domain_ops *ops = NULL;
2378 struct device_node *np;
2385 if (gpiochip->irq.parent_handler && gpiochip->can_sleep) {
2386 chip_err(gpiochip, "you cannot have chained interrupts on a chip that may sleep\n");
2390 np = gpiochip->gpiodev->dev.of_node;
2391 type = gpiochip->irq.default_type;
2394 * Specifying a default trigger is a terrible idea if DT or ACPI is
2395 * used to configure the interrupts, as you may end up with
2396 * conflicting triggers. Tell the user, and reset to NONE.
2398 if (WARN(np && type != IRQ_TYPE_NONE,
2399 "%s: Ignoring %u default trigger\n", np->full_name, type))
2400 type = IRQ_TYPE_NONE;
2402 if (has_acpi_companion(gpiochip->parent) && type != IRQ_TYPE_NONE) {
2403 acpi_handle_warn(ACPI_HANDLE(gpiochip->parent),
2404 "Ignoring %u default trigger\n", type);
2405 type = IRQ_TYPE_NONE;
2408 gpiochip->to_irq = gpiochip_to_irq;
2409 gpiochip->irq.default_type = type;
2410 gpiochip->irq.lock_key = lock_key;
2411 gpiochip->irq.request_key = request_key;
2413 /* If a parent irqdomain is provided, let's build a hierarchy */
2414 if (gpiochip_hierarchy_is_hierarchical(gpiochip)) {
2415 int ret = gpiochip_hierarchy_add_domain(gpiochip);
2419 /* Some drivers provide custom irqdomain ops */
2420 if (gpiochip->irq.domain_ops)
2421 ops = gpiochip->irq.domain_ops;
2424 ops = &gpiochip_domain_ops;
2425 gpiochip->irq.domain = irq_domain_add_simple(np,
2427 gpiochip->irq.first,
2429 if (!gpiochip->irq.domain)
2433 if (gpiochip->irq.parent_handler) {
2434 void *data = gpiochip->irq.parent_handler_data ?: gpiochip;
2436 for (i = 0; i < gpiochip->irq.num_parents; i++) {
2438 * The parent IRQ chip is already using the chip_data
2439 * for this IRQ chip, so our callbacks simply use the
2442 irq_set_chained_handler_and_data(gpiochip->irq.parents[i],
2443 gpiochip->irq.parent_handler,
2448 gpiochip_set_irq_hooks(gpiochip);
2450 acpi_gpiochip_request_interrupts(gpiochip);
2456 * gpiochip_irqchip_remove() - removes an irqchip added to a gpiochip
2457 * @gpiochip: the gpiochip to remove the irqchip from
2459 * This is called only from gpiochip_remove()
2461 static void gpiochip_irqchip_remove(struct gpio_chip *gpiochip)
2463 struct irq_chip *irqchip = gpiochip->irq.chip;
2464 unsigned int offset;
2466 acpi_gpiochip_free_interrupts(gpiochip);
2468 if (irqchip && gpiochip->irq.parent_handler) {
2469 struct gpio_irq_chip *irq = &gpiochip->irq;
2472 for (i = 0; i < irq->num_parents; i++)
2473 irq_set_chained_handler_and_data(irq->parents[i],
2477 /* Remove all IRQ mappings and delete the domain */
2478 if (gpiochip->irq.domain) {
2481 for (offset = 0; offset < gpiochip->ngpio; offset++) {
2482 if (!gpiochip_irqchip_irq_valid(gpiochip, offset))
2485 irq = irq_find_mapping(gpiochip->irq.domain, offset);
2486 irq_dispose_mapping(irq);
2489 irq_domain_remove(gpiochip->irq.domain);
2493 if (irqchip->irq_request_resources == gpiochip_irq_reqres) {
2494 irqchip->irq_request_resources = NULL;
2495 irqchip->irq_release_resources = NULL;
2497 if (irqchip->irq_enable == gpiochip_irq_enable) {
2498 irqchip->irq_enable = gpiochip->irq.irq_enable;
2499 irqchip->irq_disable = gpiochip->irq.irq_disable;
2502 gpiochip->irq.irq_enable = NULL;
2503 gpiochip->irq.irq_disable = NULL;
2504 gpiochip->irq.chip = NULL;
2506 gpiochip_irqchip_free_valid_mask(gpiochip);
2510 * gpiochip_irqchip_add_key() - adds an irqchip to a gpiochip
2511 * @gpiochip: the gpiochip to add the irqchip to
2512 * @irqchip: the irqchip to add to the gpiochip
2513 * @first_irq: if not dynamically assigned, the base (first) IRQ to
2514 * allocate gpiochip irqs from
2515 * @handler: the irq handler to use (often a predefined irq core function)
2516 * @type: the default type for IRQs on this irqchip, pass IRQ_TYPE_NONE
2517 * to have the core avoid setting up any default type in the hardware.
2518 * @threaded: whether this irqchip uses a nested thread handler
2519 * @lock_key: lockdep class for IRQ lock
2520 * @request_key: lockdep class for IRQ request
2522 * This function closely associates a certain irqchip with a certain
2523 * gpiochip, providing an irq domain to translate the local IRQs to
2524 * global irqs in the gpiolib core, and making sure that the gpiochip
2525 * is passed as chip data to all related functions. Driver callbacks
2526 * need to use gpiochip_get_data() to get their local state containers back
2527 * from the gpiochip passed as chip data. An irqdomain will be stored
2528 * in the gpiochip that shall be used by the driver to handle IRQ number
2529 * translation. The gpiochip will need to be initialized and registered
2530 * before calling this function.
2532 * This function will handle two cell:ed simple IRQs and assumes all
2533 * the pins on the gpiochip can generate a unique IRQ. Everything else
2534 * need to be open coded.
2536 int gpiochip_irqchip_add_key(struct gpio_chip *gpiochip,
2537 struct irq_chip *irqchip,
2538 unsigned int first_irq,
2539 irq_flow_handler_t handler,
2542 struct lock_class_key *lock_key,
2543 struct lock_class_key *request_key)
2545 struct device_node *of_node;
2547 if (!gpiochip || !irqchip)
2550 if (!gpiochip->parent) {
2551 pr_err("missing gpiochip .dev parent pointer\n");
2554 gpiochip->irq.threaded = threaded;
2555 of_node = gpiochip->parent->of_node;
2556 #ifdef CONFIG_OF_GPIO
2558 * If the gpiochip has an assigned OF node this takes precedence
2559 * FIXME: get rid of this and use gpiochip->parent->of_node
2562 if (gpiochip->of_node)
2563 of_node = gpiochip->of_node;
2566 * Specifying a default trigger is a terrible idea if DT or ACPI is
2567 * used to configure the interrupts, as you may end-up with
2568 * conflicting triggers. Tell the user, and reset to NONE.
2570 if (WARN(of_node && type != IRQ_TYPE_NONE,
2571 "%pOF: Ignoring %d default trigger\n", of_node, type))
2572 type = IRQ_TYPE_NONE;
2573 if (has_acpi_companion(gpiochip->parent) && type != IRQ_TYPE_NONE) {
2574 acpi_handle_warn(ACPI_HANDLE(gpiochip->parent),
2575 "Ignoring %d default trigger\n", type);
2576 type = IRQ_TYPE_NONE;
2579 gpiochip->irq.chip = irqchip;
2580 gpiochip->irq.handler = handler;
2581 gpiochip->irq.default_type = type;
2582 gpiochip->to_irq = gpiochip_to_irq;
2583 gpiochip->irq.lock_key = lock_key;
2584 gpiochip->irq.request_key = request_key;
2585 gpiochip->irq.domain = irq_domain_add_simple(of_node,
2586 gpiochip->ngpio, first_irq,
2587 &gpiochip_domain_ops, gpiochip);
2588 if (!gpiochip->irq.domain) {
2589 gpiochip->irq.chip = NULL;
2593 gpiochip_set_irq_hooks(gpiochip);
2595 acpi_gpiochip_request_interrupts(gpiochip);
2599 EXPORT_SYMBOL_GPL(gpiochip_irqchip_add_key);
2601 #else /* CONFIG_GPIOLIB_IRQCHIP */
2603 static inline int gpiochip_add_irqchip(struct gpio_chip *gpiochip,
2604 struct lock_class_key *lock_key,
2605 struct lock_class_key *request_key)
2609 static void gpiochip_irqchip_remove(struct gpio_chip *gpiochip) {}
2611 static inline int gpiochip_irqchip_init_hw(struct gpio_chip *gpiochip)
2616 static inline int gpiochip_irqchip_init_valid_mask(struct gpio_chip *gpiochip)
2620 static inline void gpiochip_irqchip_free_valid_mask(struct gpio_chip *gpiochip)
2623 #endif /* CONFIG_GPIOLIB_IRQCHIP */
2626 * gpiochip_generic_request() - request the gpio function for a pin
2627 * @chip: the gpiochip owning the GPIO
2628 * @offset: the offset of the GPIO to request for GPIO function
2630 int gpiochip_generic_request(struct gpio_chip *chip, unsigned offset)
2632 return pinctrl_gpio_request(chip->gpiodev->base + offset);
2634 EXPORT_SYMBOL_GPL(gpiochip_generic_request);
2637 * gpiochip_generic_free() - free the gpio function from a pin
2638 * @chip: the gpiochip to request the gpio function for
2639 * @offset: the offset of the GPIO to free from GPIO function
2641 void gpiochip_generic_free(struct gpio_chip *chip, unsigned offset)
2643 pinctrl_gpio_free(chip->gpiodev->base + offset);
2645 EXPORT_SYMBOL_GPL(gpiochip_generic_free);
2648 * gpiochip_generic_config() - apply configuration for a pin
2649 * @chip: the gpiochip owning the GPIO
2650 * @offset: the offset of the GPIO to apply the configuration
2651 * @config: the configuration to be applied
2653 int gpiochip_generic_config(struct gpio_chip *chip, unsigned offset,
2654 unsigned long config)
2656 return pinctrl_gpio_set_config(chip->gpiodev->base + offset, config);
2658 EXPORT_SYMBOL_GPL(gpiochip_generic_config);
2660 #ifdef CONFIG_PINCTRL
2663 * gpiochip_add_pingroup_range() - add a range for GPIO <-> pin mapping
2664 * @chip: the gpiochip to add the range for
2665 * @pctldev: the pin controller to map to
2666 * @gpio_offset: the start offset in the current gpio_chip number space
2667 * @pin_group: name of the pin group inside the pin controller
2669 * Calling this function directly from a DeviceTree-supported
2670 * pinctrl driver is DEPRECATED. Please see Section 2.1 of
2671 * Documentation/devicetree/bindings/gpio/gpio.txt on how to
2672 * bind pinctrl and gpio drivers via the "gpio-ranges" property.
2674 int gpiochip_add_pingroup_range(struct gpio_chip *chip,
2675 struct pinctrl_dev *pctldev,
2676 unsigned int gpio_offset, const char *pin_group)
2678 struct gpio_pin_range *pin_range;
2679 struct gpio_device *gdev = chip->gpiodev;
2682 pin_range = kzalloc(sizeof(*pin_range), GFP_KERNEL);
2684 chip_err(chip, "failed to allocate pin ranges\n");
2688 /* Use local offset as range ID */
2689 pin_range->range.id = gpio_offset;
2690 pin_range->range.gc = chip;
2691 pin_range->range.name = chip->label;
2692 pin_range->range.base = gdev->base + gpio_offset;
2693 pin_range->pctldev = pctldev;
2695 ret = pinctrl_get_group_pins(pctldev, pin_group,
2696 &pin_range->range.pins,
2697 &pin_range->range.npins);
2703 pinctrl_add_gpio_range(pctldev, &pin_range->range);
2705 chip_dbg(chip, "created GPIO range %d->%d ==> %s PINGRP %s\n",
2706 gpio_offset, gpio_offset + pin_range->range.npins - 1,
2707 pinctrl_dev_get_devname(pctldev), pin_group);
2709 list_add_tail(&pin_range->node, &gdev->pin_ranges);
2713 EXPORT_SYMBOL_GPL(gpiochip_add_pingroup_range);
2716 * gpiochip_add_pin_range() - add a range for GPIO <-> pin mapping
2717 * @chip: the gpiochip to add the range for
2718 * @pinctl_name: the dev_name() of the pin controller to map to
2719 * @gpio_offset: the start offset in the current gpio_chip number space
2720 * @pin_offset: the start offset in the pin controller number space
2721 * @npins: the number of pins from the offset of each pin space (GPIO and
2722 * pin controller) to accumulate in this range
2725 * 0 on success, or a negative error-code on failure.
2727 * Calling this function directly from a DeviceTree-supported
2728 * pinctrl driver is DEPRECATED. Please see Section 2.1 of
2729 * Documentation/devicetree/bindings/gpio/gpio.txt on how to
2730 * bind pinctrl and gpio drivers via the "gpio-ranges" property.
2732 int gpiochip_add_pin_range(struct gpio_chip *chip, const char *pinctl_name,
2733 unsigned int gpio_offset, unsigned int pin_offset,
2736 struct gpio_pin_range *pin_range;
2737 struct gpio_device *gdev = chip->gpiodev;
2740 pin_range = kzalloc(sizeof(*pin_range), GFP_KERNEL);
2742 chip_err(chip, "failed to allocate pin ranges\n");
2746 /* Use local offset as range ID */
2747 pin_range->range.id = gpio_offset;
2748 pin_range->range.gc = chip;
2749 pin_range->range.name = chip->label;
2750 pin_range->range.base = gdev->base + gpio_offset;
2751 pin_range->range.pin_base = pin_offset;
2752 pin_range->range.npins = npins;
2753 pin_range->pctldev = pinctrl_find_and_add_gpio_range(pinctl_name,
2755 if (IS_ERR(pin_range->pctldev)) {
2756 ret = PTR_ERR(pin_range->pctldev);
2757 chip_err(chip, "could not create pin range\n");
2761 chip_dbg(chip, "created GPIO range %d->%d ==> %s PIN %d->%d\n",
2762 gpio_offset, gpio_offset + npins - 1,
2764 pin_offset, pin_offset + npins - 1);
2766 list_add_tail(&pin_range->node, &gdev->pin_ranges);
2770 EXPORT_SYMBOL_GPL(gpiochip_add_pin_range);
2773 * gpiochip_remove_pin_ranges() - remove all the GPIO <-> pin mappings
2774 * @chip: the chip to remove all the mappings for
2776 void gpiochip_remove_pin_ranges(struct gpio_chip *chip)
2778 struct gpio_pin_range *pin_range, *tmp;
2779 struct gpio_device *gdev = chip->gpiodev;
2781 list_for_each_entry_safe(pin_range, tmp, &gdev->pin_ranges, node) {
2782 list_del(&pin_range->node);
2783 pinctrl_remove_gpio_range(pin_range->pctldev,
2788 EXPORT_SYMBOL_GPL(gpiochip_remove_pin_ranges);
2790 #endif /* CONFIG_PINCTRL */
2792 /* These "optional" allocation calls help prevent drivers from stomping
2793 * on each other, and help provide better diagnostics in debugfs.
2794 * They're called even less than the "set direction" calls.
2796 static int gpiod_request_commit(struct gpio_desc *desc, const char *label)
2798 struct gpio_chip *chip = desc->gdev->chip;
2800 unsigned long flags;
2804 label = kstrdup_const(label, GFP_KERNEL);
2809 spin_lock_irqsave(&gpio_lock, flags);
2811 /* NOTE: gpio_request() can be called in early boot,
2812 * before IRQs are enabled, for non-sleeping (SOC) GPIOs.
2815 if (test_and_set_bit(FLAG_REQUESTED, &desc->flags) == 0) {
2816 desc_set_label(desc, label ? : "?");
2824 if (chip->request) {
2825 /* chip->request may sleep */
2826 spin_unlock_irqrestore(&gpio_lock, flags);
2827 offset = gpio_chip_hwgpio(desc);
2828 if (gpiochip_line_is_valid(chip, offset))
2829 ret = chip->request(chip, offset);
2832 spin_lock_irqsave(&gpio_lock, flags);
2835 desc_set_label(desc, NULL);
2837 clear_bit(FLAG_REQUESTED, &desc->flags);
2841 if (chip->get_direction) {
2842 /* chip->get_direction may sleep */
2843 spin_unlock_irqrestore(&gpio_lock, flags);
2844 gpiod_get_direction(desc);
2845 spin_lock_irqsave(&gpio_lock, flags);
2848 spin_unlock_irqrestore(&gpio_lock, flags);
2853 * This descriptor validation needs to be inserted verbatim into each
2854 * function taking a descriptor, so we need to use a preprocessor
2855 * macro to avoid endless duplication. If the desc is NULL it is an
2856 * optional GPIO and calls should just bail out.
2858 static int validate_desc(const struct gpio_desc *desc, const char *func)
2863 pr_warn("%s: invalid GPIO (errorpointer)\n", func);
2864 return PTR_ERR(desc);
2867 pr_warn("%s: invalid GPIO (no device)\n", func);
2870 if (!desc->gdev->chip) {
2871 dev_warn(&desc->gdev->dev,
2872 "%s: backing chip is gone\n", func);
2878 #define VALIDATE_DESC(desc) do { \
2879 int __valid = validate_desc(desc, __func__); \
2884 #define VALIDATE_DESC_VOID(desc) do { \
2885 int __valid = validate_desc(desc, __func__); \
2890 int gpiod_request(struct gpio_desc *desc, const char *label)
2892 int ret = -EPROBE_DEFER;
2893 struct gpio_device *gdev;
2895 VALIDATE_DESC(desc);
2898 if (try_module_get(gdev->owner)) {
2899 ret = gpiod_request_commit(desc, label);
2901 module_put(gdev->owner);
2903 get_device(&gdev->dev);
2907 gpiod_dbg(desc, "%s: status %d\n", __func__, ret);
2912 static bool gpiod_free_commit(struct gpio_desc *desc)
2915 unsigned long flags;
2916 struct gpio_chip *chip;
2920 gpiod_unexport(desc);
2922 spin_lock_irqsave(&gpio_lock, flags);
2924 chip = desc->gdev->chip;
2925 if (chip && test_bit(FLAG_REQUESTED, &desc->flags)) {
2927 spin_unlock_irqrestore(&gpio_lock, flags);
2928 might_sleep_if(chip->can_sleep);
2929 chip->free(chip, gpio_chip_hwgpio(desc));
2930 spin_lock_irqsave(&gpio_lock, flags);
2932 kfree_const(desc->label);
2933 desc_set_label(desc, NULL);
2934 clear_bit(FLAG_ACTIVE_LOW, &desc->flags);
2935 clear_bit(FLAG_REQUESTED, &desc->flags);
2936 clear_bit(FLAG_OPEN_DRAIN, &desc->flags);
2937 clear_bit(FLAG_OPEN_SOURCE, &desc->flags);
2938 clear_bit(FLAG_PULL_UP, &desc->flags);
2939 clear_bit(FLAG_PULL_DOWN, &desc->flags);
2940 clear_bit(FLAG_BIAS_DISABLE, &desc->flags);
2941 clear_bit(FLAG_IS_HOGGED, &desc->flags);
2945 spin_unlock_irqrestore(&gpio_lock, flags);
2949 void gpiod_free(struct gpio_desc *desc)
2951 if (desc && desc->gdev && gpiod_free_commit(desc)) {
2952 module_put(desc->gdev->owner);
2953 put_device(&desc->gdev->dev);
2955 WARN_ON(extra_checks);
2960 * gpiochip_is_requested - return string iff signal was requested
2961 * @chip: controller managing the signal
2962 * @offset: of signal within controller's 0..(ngpio - 1) range
2964 * Returns NULL if the GPIO is not currently requested, else a string.
2965 * The string returned is the label passed to gpio_request(); if none has been
2966 * passed it is a meaningless, non-NULL constant.
2968 * This function is for use by GPIO controller drivers. The label can
2969 * help with diagnostics, and knowing that the signal is used as a GPIO
2970 * can help avoid accidentally multiplexing it to another controller.
2972 const char *gpiochip_is_requested(struct gpio_chip *chip, unsigned offset)
2974 struct gpio_desc *desc;
2976 if (offset >= chip->ngpio)
2979 desc = &chip->gpiodev->descs[offset];
2981 if (test_bit(FLAG_REQUESTED, &desc->flags) == 0)
2985 EXPORT_SYMBOL_GPL(gpiochip_is_requested);
2988 * gpiochip_request_own_desc - Allow GPIO chip to request its own descriptor
2990 * @hwnum: hardware number of the GPIO for which to request the descriptor
2991 * @label: label for the GPIO
2992 * @lflags: lookup flags for this GPIO or 0 if default, this can be used to
2993 * specify things like line inversion semantics with the machine flags
2994 * such as GPIO_OUT_LOW
2995 * @dflags: descriptor request flags for this GPIO or 0 if default, this
2996 * can be used to specify consumer semantics such as open drain
2998 * Function allows GPIO chip drivers to request and use their own GPIO
2999 * descriptors via gpiolib API. Difference to gpiod_request() is that this
3000 * function will not increase reference count of the GPIO chip module. This
3001 * allows the GPIO chip module to be unloaded as needed (we assume that the
3002 * GPIO chip driver handles freeing the GPIOs it has requested).
3005 * A pointer to the GPIO descriptor, or an ERR_PTR()-encoded negative error
3008 struct gpio_desc *gpiochip_request_own_desc(struct gpio_chip *chip,
3011 enum gpio_lookup_flags lflags,
3012 enum gpiod_flags dflags)
3014 struct gpio_desc *desc = gpiochip_get_desc(chip, hwnum);
3018 chip_err(chip, "failed to get GPIO descriptor\n");
3022 ret = gpiod_request_commit(desc, label);
3024 return ERR_PTR(ret);
3026 ret = gpiod_configure_flags(desc, label, lflags, dflags);
3028 chip_err(chip, "setup of own GPIO %s failed\n", label);
3029 gpiod_free_commit(desc);
3030 return ERR_PTR(ret);
3035 EXPORT_SYMBOL_GPL(gpiochip_request_own_desc);
3038 * gpiochip_free_own_desc - Free GPIO requested by the chip driver
3039 * @desc: GPIO descriptor to free
3041 * Function frees the given GPIO requested previously with
3042 * gpiochip_request_own_desc().
3044 void gpiochip_free_own_desc(struct gpio_desc *desc)
3047 gpiod_free_commit(desc);
3049 EXPORT_SYMBOL_GPL(gpiochip_free_own_desc);
3052 * Drivers MUST set GPIO direction before making get/set calls. In
3053 * some cases this is done in early boot, before IRQs are enabled.
3055 * As a rule these aren't called more than once (except for drivers
3056 * using the open-drain emulation idiom) so these are natural places
3057 * to accumulate extra debugging checks. Note that we can't (yet)
3058 * rely on gpio_request() having been called beforehand.
3061 static int gpio_set_config(struct gpio_chip *gc, unsigned int offset,
3062 enum pin_config_param mode)
3064 if (!gc->set_config)
3067 return gc->set_config(gc, offset, mode);
3070 static int gpio_set_bias(struct gpio_chip *chip, struct gpio_desc *desc)
3075 if (test_bit(FLAG_BIAS_DISABLE, &desc->flags))
3076 bias = PIN_CONFIG_BIAS_DISABLE;
3077 else if (test_bit(FLAG_PULL_UP, &desc->flags))
3078 bias = PIN_CONFIG_BIAS_PULL_UP;
3079 else if (test_bit(FLAG_PULL_DOWN, &desc->flags))
3080 bias = PIN_CONFIG_BIAS_PULL_DOWN;
3083 ret = gpio_set_config(chip, gpio_chip_hwgpio(desc), bias);
3084 if (ret != -ENOTSUPP)
3091 * gpiod_direction_input - set the GPIO direction to input
3092 * @desc: GPIO to set to input
3094 * Set the direction of the passed GPIO to input, such as gpiod_get_value() can
3095 * be called safely on it.
3097 * Return 0 in case of success, else an error code.
3099 int gpiod_direction_input(struct gpio_desc *desc)
3101 struct gpio_chip *chip;
3104 VALIDATE_DESC(desc);
3105 chip = desc->gdev->chip;
3108 * It is legal to have no .get() and .direction_input() specified if
3109 * the chip is output-only, but you can't specify .direction_input()
3110 * and not support the .get() operation, that doesn't make sense.
3112 if (!chip->get && chip->direction_input) {
3114 "%s: missing get() but have direction_input()\n",
3120 * If we have a .direction_input() callback, things are simple,
3121 * just call it. Else we are some input-only chip so try to check the
3122 * direction (if .get_direction() is supported) else we silently
3123 * assume we are in input mode after this.
3125 if (chip->direction_input) {
3126 ret = chip->direction_input(chip, gpio_chip_hwgpio(desc));
3127 } else if (chip->get_direction &&
3128 (chip->get_direction(chip, gpio_chip_hwgpio(desc)) != 1)) {
3130 "%s: missing direction_input() operation and line is output\n",
3135 clear_bit(FLAG_IS_OUT, &desc->flags);
3136 ret = gpio_set_bias(chip, desc);
3139 trace_gpio_direction(desc_to_gpio(desc), 1, ret);
3143 EXPORT_SYMBOL_GPL(gpiod_direction_input);
3145 static int gpiod_direction_output_raw_commit(struct gpio_desc *desc, int value)
3147 struct gpio_chip *gc = desc->gdev->chip;
3152 * It's OK not to specify .direction_output() if the gpiochip is
3153 * output-only, but if there is then not even a .set() operation it
3154 * is pretty tricky to drive the output line.
3156 if (!gc->set && !gc->direction_output) {
3158 "%s: missing set() and direction_output() operations\n",
3163 if (gc->direction_output) {
3164 ret = gc->direction_output(gc, gpio_chip_hwgpio(desc), val);
3166 /* Check that we are in output mode if we can */
3167 if (gc->get_direction &&
3168 gc->get_direction(gc, gpio_chip_hwgpio(desc))) {
3170 "%s: missing direction_output() operation\n",
3175 * If we can't actively set the direction, we are some
3176 * output-only chip, so just drive the output as desired.
3178 gc->set(gc, gpio_chip_hwgpio(desc), val);
3182 set_bit(FLAG_IS_OUT, &desc->flags);
3183 trace_gpio_value(desc_to_gpio(desc), 0, val);
3184 trace_gpio_direction(desc_to_gpio(desc), 0, ret);
3189 * gpiod_direction_output_raw - set the GPIO direction to output
3190 * @desc: GPIO to set to output
3191 * @value: initial output value of the GPIO
3193 * Set the direction of the passed GPIO to output, such as gpiod_set_value() can
3194 * be called safely on it. The initial value of the output must be specified
3195 * as raw value on the physical line without regard for the ACTIVE_LOW status.
3197 * Return 0 in case of success, else an error code.
3199 int gpiod_direction_output_raw(struct gpio_desc *desc, int value)
3201 VALIDATE_DESC(desc);
3202 return gpiod_direction_output_raw_commit(desc, value);
3204 EXPORT_SYMBOL_GPL(gpiod_direction_output_raw);
3207 * gpiod_direction_output - set the GPIO direction to output
3208 * @desc: GPIO to set to output
3209 * @value: initial output value of the GPIO
3211 * Set the direction of the passed GPIO to output, such as gpiod_set_value() can
3212 * be called safely on it. The initial value of the output must be specified
3213 * as the logical value of the GPIO, i.e. taking its ACTIVE_LOW status into
3216 * Return 0 in case of success, else an error code.
3218 int gpiod_direction_output(struct gpio_desc *desc, int value)
3220 struct gpio_chip *gc;
3223 VALIDATE_DESC(desc);
3224 if (test_bit(FLAG_ACTIVE_LOW, &desc->flags))
3229 /* GPIOs used for enabled IRQs shall not be set as output */
3230 if (test_bit(FLAG_USED_AS_IRQ, &desc->flags) &&
3231 test_bit(FLAG_IRQ_IS_ENABLED, &desc->flags)) {
3233 "%s: tried to set a GPIO tied to an IRQ as output\n",
3238 gc = desc->gdev->chip;
3239 if (test_bit(FLAG_OPEN_DRAIN, &desc->flags)) {
3240 /* First see if we can enable open drain in hardware */
3241 ret = gpio_set_config(gc, gpio_chip_hwgpio(desc),
3242 PIN_CONFIG_DRIVE_OPEN_DRAIN);
3244 goto set_output_value;
3245 /* Emulate open drain by not actively driving the line high */
3247 ret = gpiod_direction_input(desc);
3248 goto set_output_flag;
3251 else if (test_bit(FLAG_OPEN_SOURCE, &desc->flags)) {
3252 ret = gpio_set_config(gc, gpio_chip_hwgpio(desc),
3253 PIN_CONFIG_DRIVE_OPEN_SOURCE);
3255 goto set_output_value;
3256 /* Emulate open source by not actively driving the line low */
3258 ret = gpiod_direction_input(desc);
3259 goto set_output_flag;
3262 gpio_set_config(gc, gpio_chip_hwgpio(desc),
3263 PIN_CONFIG_DRIVE_PUSH_PULL);
3267 ret = gpio_set_bias(gc, desc);
3270 return gpiod_direction_output_raw_commit(desc, value);
3274 * When emulating open-source or open-drain functionalities by not
3275 * actively driving the line (setting mode to input) we still need to
3276 * set the IS_OUT flag or otherwise we won't be able to set the line
3280 set_bit(FLAG_IS_OUT, &desc->flags);
3283 EXPORT_SYMBOL_GPL(gpiod_direction_output);
3286 * gpiod_set_debounce - sets @debounce time for a GPIO
3287 * @desc: descriptor of the GPIO for which to set debounce time
3288 * @debounce: debounce time in microseconds
3291 * 0 on success, %-ENOTSUPP if the controller doesn't support setting the
3294 int gpiod_set_debounce(struct gpio_desc *desc, unsigned debounce)
3296 struct gpio_chip *chip;
3297 unsigned long config;
3299 VALIDATE_DESC(desc);
3300 chip = desc->gdev->chip;
3302 config = pinconf_to_config_packed(PIN_CONFIG_INPUT_DEBOUNCE, debounce);
3303 return gpio_set_config(chip, gpio_chip_hwgpio(desc), config);
3305 EXPORT_SYMBOL_GPL(gpiod_set_debounce);
3308 * gpiod_set_transitory - Lose or retain GPIO state on suspend or reset
3309 * @desc: descriptor of the GPIO for which to configure persistence
3310 * @transitory: True to lose state on suspend or reset, false for persistence
3313 * 0 on success, otherwise a negative error code.
3315 int gpiod_set_transitory(struct gpio_desc *desc, bool transitory)
3317 struct gpio_chip *chip;
3318 unsigned long packed;
3322 VALIDATE_DESC(desc);
3324 * Handle FLAG_TRANSITORY first, enabling queries to gpiolib for
3325 * persistence state.
3327 assign_bit(FLAG_TRANSITORY, &desc->flags, transitory);
3329 /* If the driver supports it, set the persistence state now */
3330 chip = desc->gdev->chip;
3331 if (!chip->set_config)
3334 packed = pinconf_to_config_packed(PIN_CONFIG_PERSIST_STATE,
3336 gpio = gpio_chip_hwgpio(desc);
3337 rc = gpio_set_config(chip, gpio, packed);
3338 if (rc == -ENOTSUPP) {
3339 dev_dbg(&desc->gdev->dev, "Persistence not supported for GPIO %d\n",
3346 EXPORT_SYMBOL_GPL(gpiod_set_transitory);
3349 * gpiod_is_active_low - test whether a GPIO is active-low or not
3350 * @desc: the gpio descriptor to test
3352 * Returns 1 if the GPIO is active-low, 0 otherwise.
3354 int gpiod_is_active_low(const struct gpio_desc *desc)
3356 VALIDATE_DESC(desc);
3357 return test_bit(FLAG_ACTIVE_LOW, &desc->flags);
3359 EXPORT_SYMBOL_GPL(gpiod_is_active_low);
3362 * gpiod_toggle_active_low - toggle whether a GPIO is active-low or not
3363 * @desc: the gpio descriptor to change
3365 void gpiod_toggle_active_low(struct gpio_desc *desc)
3367 VALIDATE_DESC_VOID(desc);
3368 change_bit(FLAG_ACTIVE_LOW, &desc->flags);
3370 EXPORT_SYMBOL_GPL(gpiod_toggle_active_low);
3372 /* I/O calls are only valid after configuration completed; the relevant
3373 * "is this a valid GPIO" error checks should already have been done.
3375 * "Get" operations are often inlinable as reading a pin value register,
3376 * and masking the relevant bit in that register.
3378 * When "set" operations are inlinable, they involve writing that mask to
3379 * one register to set a low value, or a different register to set it high.
3380 * Otherwise locking is needed, so there may be little value to inlining.
3382 *------------------------------------------------------------------------
3384 * IMPORTANT!!! The hot paths -- get/set value -- assume that callers
3385 * have requested the GPIO. That can include implicit requesting by
3386 * a direction setting call. Marking a gpio as requested locks its chip
3387 * in memory, guaranteeing that these table lookups need no more locking
3388 * and that gpiochip_remove() will fail.
3390 * REVISIT when debugging, consider adding some instrumentation to ensure
3391 * that the GPIO was actually requested.
3394 static int gpiod_get_raw_value_commit(const struct gpio_desc *desc)
3396 struct gpio_chip *chip;
3400 chip = desc->gdev->chip;
3401 offset = gpio_chip_hwgpio(desc);
3402 value = chip->get ? chip->get(chip, offset) : -EIO;
3403 value = value < 0 ? value : !!value;
3404 trace_gpio_value(desc_to_gpio(desc), 1, value);
3408 static int gpio_chip_get_multiple(struct gpio_chip *chip,
3409 unsigned long *mask, unsigned long *bits)
3411 if (chip->get_multiple) {
3412 return chip->get_multiple(chip, mask, bits);
3413 } else if (chip->get) {
3416 for_each_set_bit(i, mask, chip->ngpio) {
3417 value = chip->get(chip, i);
3420 __assign_bit(i, bits, value);
3427 int gpiod_get_array_value_complex(bool raw, bool can_sleep,
3428 unsigned int array_size,
3429 struct gpio_desc **desc_array,
3430 struct gpio_array *array_info,
3431 unsigned long *value_bitmap)
3436 * Validate array_info against desc_array and its size.
3437 * It should immediately follow desc_array if both
3438 * have been obtained from the same gpiod_get_array() call.
3440 if (array_info && array_info->desc == desc_array &&
3441 array_size <= array_info->size &&
3442 (void *)array_info == desc_array + array_info->size) {
3444 WARN_ON(array_info->chip->can_sleep);
3446 ret = gpio_chip_get_multiple(array_info->chip,
3447 array_info->get_mask,
3452 if (!raw && !bitmap_empty(array_info->invert_mask, array_size))
3453 bitmap_xor(value_bitmap, value_bitmap,
3454 array_info->invert_mask, array_size);
3456 if (bitmap_full(array_info->get_mask, array_size))
3459 i = find_first_zero_bit(array_info->get_mask, array_size);
3464 while (i < array_size) {
3465 struct gpio_chip *chip = desc_array[i]->gdev->chip;
3466 unsigned long fastpath[2 * BITS_TO_LONGS(FASTPATH_NGPIO)];
3467 unsigned long *mask, *bits;
3470 if (likely(chip->ngpio <= FASTPATH_NGPIO)) {
3473 mask = kmalloc_array(2 * BITS_TO_LONGS(chip->ngpio),
3475 can_sleep ? GFP_KERNEL : GFP_ATOMIC);
3480 bits = mask + BITS_TO_LONGS(chip->ngpio);
3481 bitmap_zero(mask, chip->ngpio);
3484 WARN_ON(chip->can_sleep);
3486 /* collect all inputs belonging to the same chip */
3489 const struct gpio_desc *desc = desc_array[i];
3490 int hwgpio = gpio_chip_hwgpio(desc);
3492 __set_bit(hwgpio, mask);
3496 i = find_next_zero_bit(array_info->get_mask,
3498 } while ((i < array_size) &&
3499 (desc_array[i]->gdev->chip == chip));
3501 ret = gpio_chip_get_multiple(chip, mask, bits);
3503 if (mask != fastpath)
3508 for (j = first; j < i; ) {
3509 const struct gpio_desc *desc = desc_array[j];
3510 int hwgpio = gpio_chip_hwgpio(desc);
3511 int value = test_bit(hwgpio, bits);
3513 if (!raw && test_bit(FLAG_ACTIVE_LOW, &desc->flags))
3515 __assign_bit(j, value_bitmap, value);
3516 trace_gpio_value(desc_to_gpio(desc), 1, value);
3520 j = find_next_zero_bit(array_info->get_mask, i,
3524 if (mask != fastpath)
3531 * gpiod_get_raw_value() - return a gpio's raw value
3532 * @desc: gpio whose value will be returned
3534 * Return the GPIO's raw value, i.e. the value of the physical line disregarding
3535 * its ACTIVE_LOW status, or negative errno on failure.
3537 * This function can be called from contexts where we cannot sleep, and will
3538 * complain if the GPIO chip functions potentially sleep.
3540 int gpiod_get_raw_value(const struct gpio_desc *desc)
3542 VALIDATE_DESC(desc);
3543 /* Should be using gpiod_get_raw_value_cansleep() */
3544 WARN_ON(desc->gdev->chip->can_sleep);
3545 return gpiod_get_raw_value_commit(desc);
3547 EXPORT_SYMBOL_GPL(gpiod_get_raw_value);
3550 * gpiod_get_value() - return a gpio's value
3551 * @desc: gpio whose value will be returned
3553 * Return the GPIO's logical value, i.e. taking the ACTIVE_LOW status into
3554 * account, or negative errno on failure.
3556 * This function can be called from contexts where we cannot sleep, and will
3557 * complain if the GPIO chip functions potentially sleep.
3559 int gpiod_get_value(const struct gpio_desc *desc)
3563 VALIDATE_DESC(desc);
3564 /* Should be using gpiod_get_value_cansleep() */
3565 WARN_ON(desc->gdev->chip->can_sleep);
3567 value = gpiod_get_raw_value_commit(desc);
3571 if (test_bit(FLAG_ACTIVE_LOW, &desc->flags))
3576 EXPORT_SYMBOL_GPL(gpiod_get_value);
3579 * gpiod_get_raw_array_value() - read raw values from an array of GPIOs
3580 * @array_size: number of elements in the descriptor array / value bitmap
3581 * @desc_array: array of GPIO descriptors whose values will be read
3582 * @array_info: information on applicability of fast bitmap processing path
3583 * @value_bitmap: bitmap to store the read values
3585 * Read the raw values of the GPIOs, i.e. the values of the physical lines
3586 * without regard for their ACTIVE_LOW status. Return 0 in case of success,
3587 * else an error code.
3589 * This function can be called from contexts where we cannot sleep,
3590 * and it will complain if the GPIO chip functions potentially sleep.
3592 int gpiod_get_raw_array_value(unsigned int array_size,
3593 struct gpio_desc **desc_array,
3594 struct gpio_array *array_info,
3595 unsigned long *value_bitmap)
3599 return gpiod_get_array_value_complex(true, false, array_size,
3600 desc_array, array_info,
3603 EXPORT_SYMBOL_GPL(gpiod_get_raw_array_value);
3606 * gpiod_get_array_value() - read values from an array of GPIOs
3607 * @array_size: number of elements in the descriptor array / value bitmap
3608 * @desc_array: array of GPIO descriptors whose values will be read
3609 * @array_info: information on applicability of fast bitmap processing path
3610 * @value_bitmap: bitmap to store the read values
3612 * Read the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status
3613 * into account. Return 0 in case of success, else an error code.
3615 * This function can be called from contexts where we cannot sleep,
3616 * and it will complain if the GPIO chip functions potentially sleep.
3618 int gpiod_get_array_value(unsigned int array_size,
3619 struct gpio_desc **desc_array,
3620 struct gpio_array *array_info,
3621 unsigned long *value_bitmap)
3625 return gpiod_get_array_value_complex(false, false, array_size,
3626 desc_array, array_info,
3629 EXPORT_SYMBOL_GPL(gpiod_get_array_value);
3632 * gpio_set_open_drain_value_commit() - Set the open drain gpio's value.
3633 * @desc: gpio descriptor whose state need to be set.
3634 * @value: Non-zero for setting it HIGH otherwise it will set to LOW.
3636 static void gpio_set_open_drain_value_commit(struct gpio_desc *desc, bool value)
3639 struct gpio_chip *chip = desc->gdev->chip;
3640 int offset = gpio_chip_hwgpio(desc);
3643 ret = chip->direction_input(chip, offset);
3645 ret = chip->direction_output(chip, offset, 0);
3647 set_bit(FLAG_IS_OUT, &desc->flags);
3649 trace_gpio_direction(desc_to_gpio(desc), value, ret);
3652 "%s: Error in set_value for open drain err %d\n",
3657 * _gpio_set_open_source_value() - Set the open source gpio's value.
3658 * @desc: gpio descriptor whose state need to be set.
3659 * @value: Non-zero for setting it HIGH otherwise it will set to LOW.
3661 static void gpio_set_open_source_value_commit(struct gpio_desc *desc, bool value)
3664 struct gpio_chip *chip = desc->gdev->chip;
3665 int offset = gpio_chip_hwgpio(desc);
3668 ret = chip->direction_output(chip, offset, 1);
3670 set_bit(FLAG_IS_OUT, &desc->flags);
3672 ret = chip->direction_input(chip, offset);
3674 trace_gpio_direction(desc_to_gpio(desc), !value, ret);
3677 "%s: Error in set_value for open source err %d\n",
3681 static void gpiod_set_raw_value_commit(struct gpio_desc *desc, bool value)
3683 struct gpio_chip *chip;
3685 chip = desc->gdev->chip;
3686 trace_gpio_value(desc_to_gpio(desc), 0, value);
3687 chip->set(chip, gpio_chip_hwgpio(desc), value);
3691 * set multiple outputs on the same chip;
3692 * use the chip's set_multiple function if available;
3693 * otherwise set the outputs sequentially;
3694 * @mask: bit mask array; one bit per output; BITS_PER_LONG bits per word
3695 * defines which outputs are to be changed
3696 * @bits: bit value array; one bit per output; BITS_PER_LONG bits per word
3697 * defines the values the outputs specified by mask are to be set to
3699 static void gpio_chip_set_multiple(struct gpio_chip *chip,
3700 unsigned long *mask, unsigned long *bits)
3702 if (chip->set_multiple) {
3703 chip->set_multiple(chip, mask, bits);
3707 /* set outputs if the corresponding mask bit is set */
3708 for_each_set_bit(i, mask, chip->ngpio)
3709 chip->set(chip, i, test_bit(i, bits));
3713 int gpiod_set_array_value_complex(bool raw, bool can_sleep,
3714 unsigned int array_size,
3715 struct gpio_desc **desc_array,
3716 struct gpio_array *array_info,
3717 unsigned long *value_bitmap)
3722 * Validate array_info against desc_array and its size.
3723 * It should immediately follow desc_array if both
3724 * have been obtained from the same gpiod_get_array() call.
3726 if (array_info && array_info->desc == desc_array &&
3727 array_size <= array_info->size &&
3728 (void *)array_info == desc_array + array_info->size) {
3730 WARN_ON(array_info->chip->can_sleep);
3732 if (!raw && !bitmap_empty(array_info->invert_mask, array_size))
3733 bitmap_xor(value_bitmap, value_bitmap,
3734 array_info->invert_mask, array_size);
3736 gpio_chip_set_multiple(array_info->chip, array_info->set_mask,
3739 if (bitmap_full(array_info->set_mask, array_size))
3742 i = find_first_zero_bit(array_info->set_mask, array_size);
3747 while (i < array_size) {
3748 struct gpio_chip *chip = desc_array[i]->gdev->chip;
3749 unsigned long fastpath[2 * BITS_TO_LONGS(FASTPATH_NGPIO)];
3750 unsigned long *mask, *bits;
3753 if (likely(chip->ngpio <= FASTPATH_NGPIO)) {
3756 mask = kmalloc_array(2 * BITS_TO_LONGS(chip->ngpio),
3758 can_sleep ? GFP_KERNEL : GFP_ATOMIC);
3763 bits = mask + BITS_TO_LONGS(chip->ngpio);
3764 bitmap_zero(mask, chip->ngpio);
3767 WARN_ON(chip->can_sleep);
3770 struct gpio_desc *desc = desc_array[i];
3771 int hwgpio = gpio_chip_hwgpio(desc);
3772 int value = test_bit(i, value_bitmap);
3775 * Pins applicable for fast input but not for
3776 * fast output processing may have been already
3777 * inverted inside the fast path, skip them.
3779 if (!raw && !(array_info &&
3780 test_bit(i, array_info->invert_mask)) &&
3781 test_bit(FLAG_ACTIVE_LOW, &desc->flags))
3783 trace_gpio_value(desc_to_gpio(desc), 0, value);
3785 * collect all normal outputs belonging to the same chip
3786 * open drain and open source outputs are set individually
3788 if (test_bit(FLAG_OPEN_DRAIN, &desc->flags) && !raw) {
3789 gpio_set_open_drain_value_commit(desc, value);
3790 } else if (test_bit(FLAG_OPEN_SOURCE, &desc->flags) && !raw) {
3791 gpio_set_open_source_value_commit(desc, value);
3793 __set_bit(hwgpio, mask);
3794 __assign_bit(hwgpio, bits, value);
3800 i = find_next_zero_bit(array_info->set_mask,
3802 } while ((i < array_size) &&
3803 (desc_array[i]->gdev->chip == chip));
3804 /* push collected bits to outputs */
3806 gpio_chip_set_multiple(chip, mask, bits);
3808 if (mask != fastpath)
3815 * gpiod_set_raw_value() - assign a gpio's raw value
3816 * @desc: gpio whose value will be assigned
3817 * @value: value to assign
3819 * Set the raw value of the GPIO, i.e. the value of its physical line without
3820 * regard for its ACTIVE_LOW status.
3822 * This function can be called from contexts where we cannot sleep, and will
3823 * complain if the GPIO chip functions potentially sleep.
3825 void gpiod_set_raw_value(struct gpio_desc *desc, int value)
3827 VALIDATE_DESC_VOID(desc);
3828 /* Should be using gpiod_set_raw_value_cansleep() */
3829 WARN_ON(desc->gdev->chip->can_sleep);
3830 gpiod_set_raw_value_commit(desc, value);
3832 EXPORT_SYMBOL_GPL(gpiod_set_raw_value);
3835 * gpiod_set_value_nocheck() - set a GPIO line value without checking
3836 * @desc: the descriptor to set the value on
3837 * @value: value to set
3839 * This sets the value of a GPIO line backing a descriptor, applying
3840 * different semantic quirks like active low and open drain/source
3843 static void gpiod_set_value_nocheck(struct gpio_desc *desc, int value)
3845 if (test_bit(FLAG_ACTIVE_LOW, &desc->flags))
3847 if (test_bit(FLAG_OPEN_DRAIN, &desc->flags))
3848 gpio_set_open_drain_value_commit(desc, value);
3849 else if (test_bit(FLAG_OPEN_SOURCE, &desc->flags))
3850 gpio_set_open_source_value_commit(desc, value);
3852 gpiod_set_raw_value_commit(desc, value);
3856 * gpiod_set_value() - assign a gpio's value
3857 * @desc: gpio whose value will be assigned
3858 * @value: value to assign
3860 * Set the logical value of the GPIO, i.e. taking its ACTIVE_LOW,
3861 * OPEN_DRAIN and OPEN_SOURCE flags into account.
3863 * This function can be called from contexts where we cannot sleep, and will
3864 * complain if the GPIO chip functions potentially sleep.
3866 void gpiod_set_value(struct gpio_desc *desc, int value)
3868 VALIDATE_DESC_VOID(desc);
3869 /* Should be using gpiod_set_value_cansleep() */
3870 WARN_ON(desc->gdev->chip->can_sleep);
3871 gpiod_set_value_nocheck(desc, value);
3873 EXPORT_SYMBOL_GPL(gpiod_set_value);
3876 * gpiod_set_raw_array_value() - assign values to an array of GPIOs
3877 * @array_size: number of elements in the descriptor array / value bitmap
3878 * @desc_array: array of GPIO descriptors whose values will be assigned
3879 * @array_info: information on applicability of fast bitmap processing path
3880 * @value_bitmap: bitmap of values to assign
3882 * Set the raw values of the GPIOs, i.e. the values of the physical lines
3883 * without regard for their ACTIVE_LOW status.
3885 * This function can be called from contexts where we cannot sleep, and will
3886 * complain if the GPIO chip functions potentially sleep.
3888 int gpiod_set_raw_array_value(unsigned int array_size,
3889 struct gpio_desc **desc_array,
3890 struct gpio_array *array_info,
3891 unsigned long *value_bitmap)
3895 return gpiod_set_array_value_complex(true, false, array_size,
3896 desc_array, array_info, value_bitmap);
3898 EXPORT_SYMBOL_GPL(gpiod_set_raw_array_value);
3901 * gpiod_set_array_value() - assign values to an array of GPIOs
3902 * @array_size: number of elements in the descriptor array / value bitmap
3903 * @desc_array: array of GPIO descriptors whose values will be assigned
3904 * @array_info: information on applicability of fast bitmap processing path
3905 * @value_bitmap: bitmap of values to assign
3907 * Set the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status
3910 * This function can be called from contexts where we cannot sleep, and will
3911 * complain if the GPIO chip functions potentially sleep.
3913 int gpiod_set_array_value(unsigned int array_size,
3914 struct gpio_desc **desc_array,
3915 struct gpio_array *array_info,
3916 unsigned long *value_bitmap)
3920 return gpiod_set_array_value_complex(false, false, array_size,
3921 desc_array, array_info,
3924 EXPORT_SYMBOL_GPL(gpiod_set_array_value);
3927 * gpiod_cansleep() - report whether gpio value access may sleep
3928 * @desc: gpio to check
3931 int gpiod_cansleep(const struct gpio_desc *desc)
3933 VALIDATE_DESC(desc);
3934 return desc->gdev->chip->can_sleep;
3936 EXPORT_SYMBOL_GPL(gpiod_cansleep);
3939 * gpiod_set_consumer_name() - set the consumer name for the descriptor
3940 * @desc: gpio to set the consumer name on
3941 * @name: the new consumer name
3943 int gpiod_set_consumer_name(struct gpio_desc *desc, const char *name)
3945 VALIDATE_DESC(desc);
3947 name = kstrdup_const(name, GFP_KERNEL);
3952 kfree_const(desc->label);
3953 desc_set_label(desc, name);
3957 EXPORT_SYMBOL_GPL(gpiod_set_consumer_name);
3960 * gpiod_to_irq() - return the IRQ corresponding to a GPIO
3961 * @desc: gpio whose IRQ will be returned (already requested)
3963 * Return the IRQ corresponding to the passed GPIO, or an error code in case of
3966 int gpiod_to_irq(const struct gpio_desc *desc)
3968 struct gpio_chip *chip;
3972 * Cannot VALIDATE_DESC() here as gpiod_to_irq() consumer semantics
3973 * requires this function to not return zero on an invalid descriptor
3974 * but rather a negative error number.
3976 if (!desc || IS_ERR(desc) || !desc->gdev || !desc->gdev->chip)
3979 chip = desc->gdev->chip;
3980 offset = gpio_chip_hwgpio(desc);
3982 int retirq = chip->to_irq(chip, offset);
3984 /* Zero means NO_IRQ */
3992 EXPORT_SYMBOL_GPL(gpiod_to_irq);
3995 * gpiochip_lock_as_irq() - lock a GPIO to be used as IRQ
3996 * @chip: the chip the GPIO to lock belongs to
3997 * @offset: the offset of the GPIO to lock as IRQ
3999 * This is used directly by GPIO drivers that want to lock down
4000 * a certain GPIO line to be used for IRQs.
4002 int gpiochip_lock_as_irq(struct gpio_chip *chip, unsigned int offset)
4004 struct gpio_desc *desc;
4006 desc = gpiochip_get_desc(chip, offset);
4008 return PTR_ERR(desc);
4011 * If it's fast: flush the direction setting if something changed
4014 if (!chip->can_sleep && chip->get_direction) {
4015 int dir = gpiod_get_direction(desc);
4018 chip_err(chip, "%s: cannot get GPIO direction\n",
4024 if (test_bit(FLAG_IS_OUT, &desc->flags)) {
4026 "%s: tried to flag a GPIO set as output for IRQ\n",
4031 set_bit(FLAG_USED_AS_IRQ, &desc->flags);
4032 set_bit(FLAG_IRQ_IS_ENABLED, &desc->flags);
4035 * If the consumer has not set up a label (such as when the
4036 * IRQ is referenced from .to_irq()) we set up a label here
4037 * so it is clear this is used as an interrupt.
4040 desc_set_label(desc, "interrupt");
4044 EXPORT_SYMBOL_GPL(gpiochip_lock_as_irq);
4047 * gpiochip_unlock_as_irq() - unlock a GPIO used as IRQ
4048 * @chip: the chip the GPIO to lock belongs to
4049 * @offset: the offset of the GPIO to lock as IRQ
4051 * This is used directly by GPIO drivers that want to indicate
4052 * that a certain GPIO is no longer used exclusively for IRQ.
4054 void gpiochip_unlock_as_irq(struct gpio_chip *chip, unsigned int offset)
4056 struct gpio_desc *desc;
4058 desc = gpiochip_get_desc(chip, offset);
4062 clear_bit(FLAG_USED_AS_IRQ, &desc->flags);
4063 clear_bit(FLAG_IRQ_IS_ENABLED, &desc->flags);
4065 /* If we only had this marking, erase it */
4066 if (desc->label && !strcmp(desc->label, "interrupt"))
4067 desc_set_label(desc, NULL);
4069 EXPORT_SYMBOL_GPL(gpiochip_unlock_as_irq);
4071 void gpiochip_disable_irq(struct gpio_chip *chip, unsigned int offset)
4073 struct gpio_desc *desc = gpiochip_get_desc(chip, offset);
4075 if (!IS_ERR(desc) &&
4076 !WARN_ON(!test_bit(FLAG_USED_AS_IRQ, &desc->flags)))
4077 clear_bit(FLAG_IRQ_IS_ENABLED, &desc->flags);
4079 EXPORT_SYMBOL_GPL(gpiochip_disable_irq);
4081 void gpiochip_enable_irq(struct gpio_chip *chip, unsigned int offset)
4083 struct gpio_desc *desc = gpiochip_get_desc(chip, offset);
4085 if (!IS_ERR(desc) &&
4086 !WARN_ON(!test_bit(FLAG_USED_AS_IRQ, &desc->flags))) {
4087 WARN_ON(test_bit(FLAG_IS_OUT, &desc->flags));
4088 set_bit(FLAG_IRQ_IS_ENABLED, &desc->flags);
4091 EXPORT_SYMBOL_GPL(gpiochip_enable_irq);
4093 bool gpiochip_line_is_irq(struct gpio_chip *chip, unsigned int offset)
4095 if (offset >= chip->ngpio)
4098 return test_bit(FLAG_USED_AS_IRQ, &chip->gpiodev->descs[offset].flags);
4100 EXPORT_SYMBOL_GPL(gpiochip_line_is_irq);
4102 int gpiochip_reqres_irq(struct gpio_chip *chip, unsigned int offset)
4106 if (!try_module_get(chip->gpiodev->owner))
4109 ret = gpiochip_lock_as_irq(chip, offset);
4111 chip_err(chip, "unable to lock HW IRQ %u for IRQ\n", offset);
4112 module_put(chip->gpiodev->owner);
4117 EXPORT_SYMBOL_GPL(gpiochip_reqres_irq);
4119 void gpiochip_relres_irq(struct gpio_chip *chip, unsigned int offset)
4121 gpiochip_unlock_as_irq(chip, offset);
4122 module_put(chip->gpiodev->owner);
4124 EXPORT_SYMBOL_GPL(gpiochip_relres_irq);
4126 bool gpiochip_line_is_open_drain(struct gpio_chip *chip, unsigned int offset)
4128 if (offset >= chip->ngpio)
4131 return test_bit(FLAG_OPEN_DRAIN, &chip->gpiodev->descs[offset].flags);
4133 EXPORT_SYMBOL_GPL(gpiochip_line_is_open_drain);
4135 bool gpiochip_line_is_open_source(struct gpio_chip *chip, unsigned int offset)
4137 if (offset >= chip->ngpio)
4140 return test_bit(FLAG_OPEN_SOURCE, &chip->gpiodev->descs[offset].flags);
4142 EXPORT_SYMBOL_GPL(gpiochip_line_is_open_source);
4144 bool gpiochip_line_is_persistent(struct gpio_chip *chip, unsigned int offset)
4146 if (offset >= chip->ngpio)
4149 return !test_bit(FLAG_TRANSITORY, &chip->gpiodev->descs[offset].flags);
4151 EXPORT_SYMBOL_GPL(gpiochip_line_is_persistent);
4154 * gpiod_get_raw_value_cansleep() - return a gpio's raw value
4155 * @desc: gpio whose value will be returned
4157 * Return the GPIO's raw value, i.e. the value of the physical line disregarding
4158 * its ACTIVE_LOW status, or negative errno on failure.
4160 * This function is to be called from contexts that can sleep.
4162 int gpiod_get_raw_value_cansleep(const struct gpio_desc *desc)
4164 might_sleep_if(extra_checks);
4165 VALIDATE_DESC(desc);
4166 return gpiod_get_raw_value_commit(desc);
4168 EXPORT_SYMBOL_GPL(gpiod_get_raw_value_cansleep);
4171 * gpiod_get_value_cansleep() - return a gpio's value
4172 * @desc: gpio whose value will be returned
4174 * Return the GPIO's logical value, i.e. taking the ACTIVE_LOW status into
4175 * account, or negative errno on failure.
4177 * This function is to be called from contexts that can sleep.
4179 int gpiod_get_value_cansleep(const struct gpio_desc *desc)
4183 might_sleep_if(extra_checks);
4184 VALIDATE_DESC(desc);
4185 value = gpiod_get_raw_value_commit(desc);
4189 if (test_bit(FLAG_ACTIVE_LOW, &desc->flags))
4194 EXPORT_SYMBOL_GPL(gpiod_get_value_cansleep);
4197 * gpiod_get_raw_array_value_cansleep() - read raw values from an array of GPIOs
4198 * @array_size: number of elements in the descriptor array / value bitmap
4199 * @desc_array: array of GPIO descriptors whose values will be read
4200 * @array_info: information on applicability of fast bitmap processing path
4201 * @value_bitmap: bitmap to store the read values
4203 * Read the raw values of the GPIOs, i.e. the values of the physical lines
4204 * without regard for their ACTIVE_LOW status. Return 0 in case of success,
4205 * else an error code.
4207 * This function is to be called from contexts that can sleep.
4209 int gpiod_get_raw_array_value_cansleep(unsigned int array_size,
4210 struct gpio_desc **desc_array,
4211 struct gpio_array *array_info,
4212 unsigned long *value_bitmap)
4214 might_sleep_if(extra_checks);
4217 return gpiod_get_array_value_complex(true, true, array_size,
4218 desc_array, array_info,
4221 EXPORT_SYMBOL_GPL(gpiod_get_raw_array_value_cansleep);
4224 * gpiod_get_array_value_cansleep() - read values from an array of GPIOs
4225 * @array_size: number of elements in the descriptor array / value bitmap
4226 * @desc_array: array of GPIO descriptors whose values will be read
4227 * @array_info: information on applicability of fast bitmap processing path
4228 * @value_bitmap: bitmap to store the read values
4230 * Read the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status
4231 * into account. Return 0 in case of success, else an error code.
4233 * This function is to be called from contexts that can sleep.
4235 int gpiod_get_array_value_cansleep(unsigned int array_size,
4236 struct gpio_desc **desc_array,
4237 struct gpio_array *array_info,
4238 unsigned long *value_bitmap)
4240 might_sleep_if(extra_checks);
4243 return gpiod_get_array_value_complex(false, true, array_size,
4244 desc_array, array_info,
4247 EXPORT_SYMBOL_GPL(gpiod_get_array_value_cansleep);
4250 * gpiod_set_raw_value_cansleep() - assign a gpio's raw value
4251 * @desc: gpio whose value will be assigned
4252 * @value: value to assign
4254 * Set the raw value of the GPIO, i.e. the value of its physical line without
4255 * regard for its ACTIVE_LOW status.
4257 * This function is to be called from contexts that can sleep.
4259 void gpiod_set_raw_value_cansleep(struct gpio_desc *desc, int value)
4261 might_sleep_if(extra_checks);
4262 VALIDATE_DESC_VOID(desc);
4263 gpiod_set_raw_value_commit(desc, value);
4265 EXPORT_SYMBOL_GPL(gpiod_set_raw_value_cansleep);
4268 * gpiod_set_value_cansleep() - assign a gpio's value
4269 * @desc: gpio whose value will be assigned
4270 * @value: value to assign
4272 * Set the logical value of the GPIO, i.e. taking its ACTIVE_LOW status into
4275 * This function is to be called from contexts that can sleep.
4277 void gpiod_set_value_cansleep(struct gpio_desc *desc, int value)
4279 might_sleep_if(extra_checks);
4280 VALIDATE_DESC_VOID(desc);
4281 gpiod_set_value_nocheck(desc, value);
4283 EXPORT_SYMBOL_GPL(gpiod_set_value_cansleep);
4286 * gpiod_set_raw_array_value_cansleep() - assign values to an array of GPIOs
4287 * @array_size: number of elements in the descriptor array / value bitmap
4288 * @desc_array: array of GPIO descriptors whose values will be assigned
4289 * @array_info: information on applicability of fast bitmap processing path
4290 * @value_bitmap: bitmap of values to assign
4292 * Set the raw values of the GPIOs, i.e. the values of the physical lines
4293 * without regard for their ACTIVE_LOW status.
4295 * This function is to be called from contexts that can sleep.
4297 int gpiod_set_raw_array_value_cansleep(unsigned int array_size,
4298 struct gpio_desc **desc_array,
4299 struct gpio_array *array_info,
4300 unsigned long *value_bitmap)
4302 might_sleep_if(extra_checks);
4305 return gpiod_set_array_value_complex(true, true, array_size, desc_array,
4306 array_info, value_bitmap);
4308 EXPORT_SYMBOL_GPL(gpiod_set_raw_array_value_cansleep);
4311 * gpiod_add_lookup_tables() - register GPIO device consumers
4312 * @tables: list of tables of consumers to register
4313 * @n: number of tables in the list
4315 void gpiod_add_lookup_tables(struct gpiod_lookup_table **tables, size_t n)
4319 mutex_lock(&gpio_lookup_lock);
4321 for (i = 0; i < n; i++)
4322 list_add_tail(&tables[i]->list, &gpio_lookup_list);
4324 mutex_unlock(&gpio_lookup_lock);
4328 * gpiod_set_array_value_cansleep() - assign values to an array of GPIOs
4329 * @array_size: number of elements in the descriptor array / value bitmap
4330 * @desc_array: array of GPIO descriptors whose values will be assigned
4331 * @array_info: information on applicability of fast bitmap processing path
4332 * @value_bitmap: bitmap of values to assign
4334 * Set the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status
4337 * This function is to be called from contexts that can sleep.
4339 int gpiod_set_array_value_cansleep(unsigned int array_size,
4340 struct gpio_desc **desc_array,
4341 struct gpio_array *array_info,
4342 unsigned long *value_bitmap)
4344 might_sleep_if(extra_checks);
4347 return gpiod_set_array_value_complex(false, true, array_size,
4348 desc_array, array_info,
4351 EXPORT_SYMBOL_GPL(gpiod_set_array_value_cansleep);
4354 * gpiod_add_lookup_table() - register GPIO device consumers
4355 * @table: table of consumers to register
4357 void gpiod_add_lookup_table(struct gpiod_lookup_table *table)
4359 mutex_lock(&gpio_lookup_lock);
4361 list_add_tail(&table->list, &gpio_lookup_list);
4363 mutex_unlock(&gpio_lookup_lock);
4365 EXPORT_SYMBOL_GPL(gpiod_add_lookup_table);
4368 * gpiod_remove_lookup_table() - unregister GPIO device consumers
4369 * @table: table of consumers to unregister
4371 void gpiod_remove_lookup_table(struct gpiod_lookup_table *table)
4373 mutex_lock(&gpio_lookup_lock);
4375 list_del(&table->list);
4377 mutex_unlock(&gpio_lookup_lock);
4379 EXPORT_SYMBOL_GPL(gpiod_remove_lookup_table);
4382 * gpiod_add_hogs() - register a set of GPIO hogs from machine code
4383 * @hogs: table of gpio hog entries with a zeroed sentinel at the end
4385 void gpiod_add_hogs(struct gpiod_hog *hogs)
4387 struct gpio_chip *chip;
4388 struct gpiod_hog *hog;
4390 mutex_lock(&gpio_machine_hogs_mutex);
4392 for (hog = &hogs[0]; hog->chip_label; hog++) {
4393 list_add_tail(&hog->list, &gpio_machine_hogs);
4396 * The chip may have been registered earlier, so check if it
4397 * exists and, if so, try to hog the line now.
4399 chip = find_chip_by_name(hog->chip_label);
4401 gpiochip_machine_hog(chip, hog);
4404 mutex_unlock(&gpio_machine_hogs_mutex);
4406 EXPORT_SYMBOL_GPL(gpiod_add_hogs);
4408 static struct gpiod_lookup_table *gpiod_find_lookup_table(struct device *dev)
4410 const char *dev_id = dev ? dev_name(dev) : NULL;
4411 struct gpiod_lookup_table *table;
4413 mutex_lock(&gpio_lookup_lock);
4415 list_for_each_entry(table, &gpio_lookup_list, list) {
4416 if (table->dev_id && dev_id) {
4418 * Valid strings on both ends, must be identical to have
4421 if (!strcmp(table->dev_id, dev_id))
4425 * One of the pointers is NULL, so both must be to have
4428 if (dev_id == table->dev_id)
4435 mutex_unlock(&gpio_lookup_lock);
4439 static struct gpio_desc *gpiod_find(struct device *dev, const char *con_id,
4440 unsigned int idx, unsigned long *flags)
4442 struct gpio_desc *desc = ERR_PTR(-ENOENT);
4443 struct gpiod_lookup_table *table;
4444 struct gpiod_lookup *p;
4446 table = gpiod_find_lookup_table(dev);
4450 for (p = &table->table[0]; p->chip_label; p++) {
4451 struct gpio_chip *chip;
4453 /* idx must always match exactly */
4457 /* If the lookup entry has a con_id, require exact match */
4458 if (p->con_id && (!con_id || strcmp(p->con_id, con_id)))
4461 chip = find_chip_by_name(p->chip_label);
4465 * As the lookup table indicates a chip with
4466 * p->chip_label should exist, assume it may
4467 * still appear later and let the interested
4468 * consumer be probed again or let the Deferred
4469 * Probe infrastructure handle the error.
4471 dev_warn(dev, "cannot find GPIO chip %s, deferring\n",
4473 return ERR_PTR(-EPROBE_DEFER);
4476 if (chip->ngpio <= p->chip_hwnum) {
4478 "requested GPIO %u (%u) is out of range [0..%u] for chip %s\n",
4479 idx, p->chip_hwnum, chip->ngpio - 1,
4481 return ERR_PTR(-EINVAL);
4484 desc = gpiochip_get_desc(chip, p->chip_hwnum);
4493 static int platform_gpio_count(struct device *dev, const char *con_id)
4495 struct gpiod_lookup_table *table;
4496 struct gpiod_lookup *p;
4497 unsigned int count = 0;
4499 table = gpiod_find_lookup_table(dev);
4503 for (p = &table->table[0]; p->chip_label; p++) {
4504 if ((con_id && p->con_id && !strcmp(con_id, p->con_id)) ||
4505 (!con_id && !p->con_id))
4515 * fwnode_gpiod_get_index - obtain a GPIO from firmware node
4516 * @fwnode: handle of the firmware node
4517 * @con_id: function within the GPIO consumer
4518 * @index: index of the GPIO to obtain for the consumer
4519 * @flags: GPIO initialization flags
4520 * @label: label to attach to the requested GPIO
4522 * This function can be used for drivers that get their configuration
4523 * from opaque firmware.
4525 * The function properly finds the corresponding GPIO using whatever is the
4526 * underlying firmware interface and then makes sure that the GPIO
4527 * descriptor is requested before it is returned to the caller.
4530 * On successful request the GPIO pin is configured in accordance with
4533 * In case of error an ERR_PTR() is returned.
4535 struct gpio_desc *fwnode_gpiod_get_index(struct fwnode_handle *fwnode,
4536 const char *con_id, int index,
4537 enum gpiod_flags flags,
4540 struct gpio_desc *desc;
4541 char prop_name[32]; /* 32 is max size of property name */
4544 for (i = 0; i < ARRAY_SIZE(gpio_suffixes); i++) {
4546 snprintf(prop_name, sizeof(prop_name), "%s-%s",
4547 con_id, gpio_suffixes[i]);
4549 snprintf(prop_name, sizeof(prop_name), "%s",
4552 desc = fwnode_get_named_gpiod(fwnode, prop_name, index, flags,
4554 if (!IS_ERR(desc) || (PTR_ERR(desc) != -ENOENT))
4560 EXPORT_SYMBOL_GPL(fwnode_gpiod_get_index);
4563 * gpiod_count - return the number of GPIOs associated with a device / function
4564 * or -ENOENT if no GPIO has been assigned to the requested function
4565 * @dev: GPIO consumer, can be NULL for system-global GPIOs
4566 * @con_id: function within the GPIO consumer
4568 int gpiod_count(struct device *dev, const char *con_id)
4570 int count = -ENOENT;
4572 if (IS_ENABLED(CONFIG_OF) && dev && dev->of_node)
4573 count = of_gpio_get_count(dev, con_id);
4574 else if (IS_ENABLED(CONFIG_ACPI) && dev && ACPI_HANDLE(dev))
4575 count = acpi_gpio_count(dev, con_id);
4578 count = platform_gpio_count(dev, con_id);
4582 EXPORT_SYMBOL_GPL(gpiod_count);
4585 * gpiod_get - obtain a GPIO for a given GPIO function
4586 * @dev: GPIO consumer, can be NULL for system-global GPIOs
4587 * @con_id: function within the GPIO consumer
4588 * @flags: optional GPIO initialization flags
4590 * Return the GPIO descriptor corresponding to the function con_id of device
4591 * dev, -ENOENT if no GPIO has been assigned to the requested function, or
4592 * another IS_ERR() code if an error occurred while trying to acquire the GPIO.
4594 struct gpio_desc *__must_check gpiod_get(struct device *dev, const char *con_id,
4595 enum gpiod_flags flags)
4597 return gpiod_get_index(dev, con_id, 0, flags);
4599 EXPORT_SYMBOL_GPL(gpiod_get);
4602 * gpiod_get_optional - obtain an optional GPIO for a given GPIO function
4603 * @dev: GPIO consumer, can be NULL for system-global GPIOs
4604 * @con_id: function within the GPIO consumer
4605 * @flags: optional GPIO initialization flags
4607 * This is equivalent to gpiod_get(), except that when no GPIO was assigned to
4608 * the requested function it will return NULL. This is convenient for drivers
4609 * that need to handle optional GPIOs.
4611 struct gpio_desc *__must_check gpiod_get_optional(struct device *dev,
4613 enum gpiod_flags flags)
4615 return gpiod_get_index_optional(dev, con_id, 0, flags);
4617 EXPORT_SYMBOL_GPL(gpiod_get_optional);
4621 * gpiod_configure_flags - helper function to configure a given GPIO
4622 * @desc: gpio whose value will be assigned
4623 * @con_id: function within the GPIO consumer
4624 * @lflags: bitmask of gpio_lookup_flags GPIO_* values - returned from
4625 * of_find_gpio() or of_get_gpio_hog()
4626 * @dflags: gpiod_flags - optional GPIO initialization flags
4628 * Return 0 on success, -ENOENT if no GPIO has been assigned to the
4629 * requested function and/or index, or another IS_ERR() code if an error
4630 * occurred while trying to acquire the GPIO.
4632 int gpiod_configure_flags(struct gpio_desc *desc, const char *con_id,
4633 unsigned long lflags, enum gpiod_flags dflags)
4637 if (lflags & GPIO_ACTIVE_LOW)
4638 set_bit(FLAG_ACTIVE_LOW, &desc->flags);
4640 if (lflags & GPIO_OPEN_DRAIN)
4641 set_bit(FLAG_OPEN_DRAIN, &desc->flags);
4642 else if (dflags & GPIOD_FLAGS_BIT_OPEN_DRAIN) {
4644 * This enforces open drain mode from the consumer side.
4645 * This is necessary for some busses like I2C, but the lookup
4646 * should *REALLY* have specified them as open drain in the
4647 * first place, so print a little warning here.
4649 set_bit(FLAG_OPEN_DRAIN, &desc->flags);
4651 "enforced open drain please flag it properly in DT/ACPI DSDT/board file\n");
4654 if (lflags & GPIO_OPEN_SOURCE)
4655 set_bit(FLAG_OPEN_SOURCE, &desc->flags);
4657 if ((lflags & GPIO_PULL_UP) && (lflags & GPIO_PULL_DOWN)) {
4659 "both pull-up and pull-down enabled, invalid configuration\n");
4663 if (lflags & GPIO_PULL_UP)
4664 set_bit(FLAG_PULL_UP, &desc->flags);
4665 else if (lflags & GPIO_PULL_DOWN)
4666 set_bit(FLAG_PULL_DOWN, &desc->flags);
4668 ret = gpiod_set_transitory(desc, (lflags & GPIO_TRANSITORY));
4672 /* No particular flag request, return here... */
4673 if (!(dflags & GPIOD_FLAGS_BIT_DIR_SET)) {
4674 pr_debug("no flags found for %s\n", con_id);
4679 if (dflags & GPIOD_FLAGS_BIT_DIR_OUT)
4680 ret = gpiod_direction_output(desc,
4681 !!(dflags & GPIOD_FLAGS_BIT_DIR_VAL));
4683 ret = gpiod_direction_input(desc);
4689 * gpiod_get_index - obtain a GPIO from a multi-index GPIO function
4690 * @dev: GPIO consumer, can be NULL for system-global GPIOs
4691 * @con_id: function within the GPIO consumer
4692 * @idx: index of the GPIO to obtain in the consumer
4693 * @flags: optional GPIO initialization flags
4695 * This variant of gpiod_get() allows to access GPIOs other than the first
4696 * defined one for functions that define several GPIOs.
4698 * Return a valid GPIO descriptor, -ENOENT if no GPIO has been assigned to the
4699 * requested function and/or index, or another IS_ERR() code if an error
4700 * occurred while trying to acquire the GPIO.
4702 struct gpio_desc *__must_check gpiod_get_index(struct device *dev,
4705 enum gpiod_flags flags)
4707 unsigned long lookupflags = GPIO_LOOKUP_FLAGS_DEFAULT;
4708 struct gpio_desc *desc = NULL;
4710 /* Maybe we have a device name, maybe not */
4711 const char *devname = dev ? dev_name(dev) : "?";
4713 dev_dbg(dev, "GPIO lookup for consumer %s\n", con_id);
4716 /* Using device tree? */
4717 if (IS_ENABLED(CONFIG_OF) && dev->of_node) {
4718 dev_dbg(dev, "using device tree for GPIO lookup\n");
4719 desc = of_find_gpio(dev, con_id, idx, &lookupflags);
4720 } else if (ACPI_COMPANION(dev)) {
4721 dev_dbg(dev, "using ACPI for GPIO lookup\n");
4722 desc = acpi_find_gpio(dev, con_id, idx, &flags, &lookupflags);
4727 * Either we are not using DT or ACPI, or their lookup did not return
4728 * a result. In that case, use platform lookup as a fallback.
4730 if (!desc || desc == ERR_PTR(-ENOENT)) {
4731 dev_dbg(dev, "using lookup tables for GPIO lookup\n");
4732 desc = gpiod_find(dev, con_id, idx, &lookupflags);
4736 dev_dbg(dev, "No GPIO consumer %s found\n", con_id);
4741 * If a connection label was passed use that, else attempt to use
4742 * the device name as label
4744 ret = gpiod_request(desc, con_id ? con_id : devname);
4746 if (ret == -EBUSY && flags & GPIOD_FLAGS_BIT_NONEXCLUSIVE) {
4748 * This happens when there are several consumers for
4749 * the same GPIO line: we just return here without
4750 * further initialization. It is a bit if a hack.
4751 * This is necessary to support fixed regulators.
4753 * FIXME: Make this more sane and safe.
4755 dev_info(dev, "nonexclusive access to GPIO for %s\n",
4756 con_id ? con_id : devname);
4759 return ERR_PTR(ret);
4763 ret = gpiod_configure_flags(desc, con_id, lookupflags, flags);
4765 dev_dbg(dev, "setup of GPIO %s failed\n", con_id);
4767 return ERR_PTR(ret);
4772 EXPORT_SYMBOL_GPL(gpiod_get_index);
4775 * fwnode_get_named_gpiod - obtain a GPIO from firmware node
4776 * @fwnode: handle of the firmware node
4777 * @propname: name of the firmware property representing the GPIO
4778 * @index: index of the GPIO to obtain for the consumer
4779 * @dflags: GPIO initialization flags
4780 * @label: label to attach to the requested GPIO
4782 * This function can be used for drivers that get their configuration
4783 * from opaque firmware.
4785 * The function properly finds the corresponding GPIO using whatever is the
4786 * underlying firmware interface and then makes sure that the GPIO
4787 * descriptor is requested before it is returned to the caller.
4790 * On successful request the GPIO pin is configured in accordance with
4793 * In case of error an ERR_PTR() is returned.
4795 struct gpio_desc *fwnode_get_named_gpiod(struct fwnode_handle *fwnode,
4796 const char *propname, int index,
4797 enum gpiod_flags dflags,
4800 unsigned long lflags = GPIO_LOOKUP_FLAGS_DEFAULT;
4801 struct gpio_desc *desc = ERR_PTR(-ENODEV);
4805 return ERR_PTR(-EINVAL);
4807 if (is_of_node(fwnode)) {
4808 desc = gpiod_get_from_of_node(to_of_node(fwnode),
4813 } else if (is_acpi_node(fwnode)) {
4814 struct acpi_gpio_info info;
4816 desc = acpi_node_get_gpiod(fwnode, propname, index, &info);
4820 acpi_gpio_update_gpiod_flags(&dflags, &info);
4821 acpi_gpio_update_gpiod_lookup_flags(&lflags, &info);
4824 /* Currently only ACPI takes this path */
4825 ret = gpiod_request(desc, label);
4827 return ERR_PTR(ret);
4829 ret = gpiod_configure_flags(desc, propname, lflags, dflags);
4832 return ERR_PTR(ret);
4837 EXPORT_SYMBOL_GPL(fwnode_get_named_gpiod);
4840 * gpiod_get_index_optional - obtain an optional GPIO from a multi-index GPIO
4842 * @dev: GPIO consumer, can be NULL for system-global GPIOs
4843 * @con_id: function within the GPIO consumer
4844 * @index: index of the GPIO to obtain in the consumer
4845 * @flags: optional GPIO initialization flags
4847 * This is equivalent to gpiod_get_index(), except that when no GPIO with the
4848 * specified index was assigned to the requested function it will return NULL.
4849 * This is convenient for drivers that need to handle optional GPIOs.
4851 struct gpio_desc *__must_check gpiod_get_index_optional(struct device *dev,
4854 enum gpiod_flags flags)
4856 struct gpio_desc *desc;
4858 desc = gpiod_get_index(dev, con_id, index, flags);
4860 if (PTR_ERR(desc) == -ENOENT)
4866 EXPORT_SYMBOL_GPL(gpiod_get_index_optional);
4869 * gpiod_hog - Hog the specified GPIO desc given the provided flags
4870 * @desc: gpio whose value will be assigned
4871 * @name: gpio line name
4872 * @lflags: bitmask of gpio_lookup_flags GPIO_* values - returned from
4873 * of_find_gpio() or of_get_gpio_hog()
4874 * @dflags: gpiod_flags - optional GPIO initialization flags
4876 int gpiod_hog(struct gpio_desc *desc, const char *name,
4877 unsigned long lflags, enum gpiod_flags dflags)
4879 struct gpio_chip *chip;
4880 struct gpio_desc *local_desc;
4884 chip = gpiod_to_chip(desc);
4885 hwnum = gpio_chip_hwgpio(desc);
4887 local_desc = gpiochip_request_own_desc(chip, hwnum, name,
4889 if (IS_ERR(local_desc)) {
4890 ret = PTR_ERR(local_desc);
4891 pr_err("requesting hog GPIO %s (chip %s, offset %d) failed, %d\n",
4892 name, chip->label, hwnum, ret);
4896 /* Mark GPIO as hogged so it can be identified and removed later */
4897 set_bit(FLAG_IS_HOGGED, &desc->flags);
4899 pr_info("GPIO line %d (%s) hogged as %s%s\n",
4900 desc_to_gpio(desc), name,
4901 (dflags & GPIOD_FLAGS_BIT_DIR_OUT) ? "output" : "input",
4902 (dflags & GPIOD_FLAGS_BIT_DIR_OUT) ?
4903 (dflags & GPIOD_FLAGS_BIT_DIR_VAL) ? "/high" : "/low" : "");
4909 * gpiochip_free_hogs - Scan gpio-controller chip and release GPIO hog
4910 * @chip: gpio chip to act on
4912 static void gpiochip_free_hogs(struct gpio_chip *chip)
4916 for (id = 0; id < chip->ngpio; id++) {
4917 if (test_bit(FLAG_IS_HOGGED, &chip->gpiodev->descs[id].flags))
4918 gpiochip_free_own_desc(&chip->gpiodev->descs[id]);
4923 * gpiod_get_array - obtain multiple GPIOs from a multi-index GPIO function
4924 * @dev: GPIO consumer, can be NULL for system-global GPIOs
4925 * @con_id: function within the GPIO consumer
4926 * @flags: optional GPIO initialization flags
4928 * This function acquires all the GPIOs defined under a given function.
4930 * Return a struct gpio_descs containing an array of descriptors, -ENOENT if
4931 * no GPIO has been assigned to the requested function, or another IS_ERR()
4932 * code if an error occurred while trying to acquire the GPIOs.
4934 struct gpio_descs *__must_check gpiod_get_array(struct device *dev,
4936 enum gpiod_flags flags)
4938 struct gpio_desc *desc;
4939 struct gpio_descs *descs;
4940 struct gpio_array *array_info = NULL;
4941 struct gpio_chip *chip;
4942 int count, bitmap_size;
4944 count = gpiod_count(dev, con_id);
4946 return ERR_PTR(count);
4948 descs = kzalloc(struct_size(descs, desc, count), GFP_KERNEL);
4950 return ERR_PTR(-ENOMEM);
4952 for (descs->ndescs = 0; descs->ndescs < count; ) {
4953 desc = gpiod_get_index(dev, con_id, descs->ndescs, flags);
4955 gpiod_put_array(descs);
4956 return ERR_CAST(desc);
4959 descs->desc[descs->ndescs] = desc;
4961 chip = gpiod_to_chip(desc);
4963 * If pin hardware number of array member 0 is also 0, select
4964 * its chip as a candidate for fast bitmap processing path.
4966 if (descs->ndescs == 0 && gpio_chip_hwgpio(desc) == 0) {
4967 struct gpio_descs *array;
4969 bitmap_size = BITS_TO_LONGS(chip->ngpio > count ?
4970 chip->ngpio : count);
4972 array = kzalloc(struct_size(descs, desc, count) +
4973 struct_size(array_info, invert_mask,
4974 3 * bitmap_size), GFP_KERNEL);
4976 gpiod_put_array(descs);
4977 return ERR_PTR(-ENOMEM);
4980 memcpy(array, descs,
4981 struct_size(descs, desc, descs->ndescs + 1));
4985 array_info = (void *)(descs->desc + count);
4986 array_info->get_mask = array_info->invert_mask +
4988 array_info->set_mask = array_info->get_mask +
4991 array_info->desc = descs->desc;
4992 array_info->size = count;
4993 array_info->chip = chip;
4994 bitmap_set(array_info->get_mask, descs->ndescs,
4995 count - descs->ndescs);
4996 bitmap_set(array_info->set_mask, descs->ndescs,
4997 count - descs->ndescs);
4998 descs->info = array_info;
5000 /* Unmark array members which don't belong to the 'fast' chip */
5001 if (array_info && array_info->chip != chip) {
5002 __clear_bit(descs->ndescs, array_info->get_mask);
5003 __clear_bit(descs->ndescs, array_info->set_mask);
5006 * Detect array members which belong to the 'fast' chip
5007 * but their pins are not in hardware order.
5009 else if (array_info &&
5010 gpio_chip_hwgpio(desc) != descs->ndescs) {
5012 * Don't use fast path if all array members processed so
5013 * far belong to the same chip as this one but its pin
5014 * hardware number is different from its array index.
5016 if (bitmap_full(array_info->get_mask, descs->ndescs)) {
5019 __clear_bit(descs->ndescs,
5020 array_info->get_mask);
5021 __clear_bit(descs->ndescs,
5022 array_info->set_mask);
5024 } else if (array_info) {
5025 /* Exclude open drain or open source from fast output */
5026 if (gpiochip_line_is_open_drain(chip, descs->ndescs) ||
5027 gpiochip_line_is_open_source(chip, descs->ndescs))
5028 __clear_bit(descs->ndescs,
5029 array_info->set_mask);
5030 /* Identify 'fast' pins which require invertion */
5031 if (gpiod_is_active_low(desc))
5032 __set_bit(descs->ndescs,
5033 array_info->invert_mask);
5040 "GPIO array info: chip=%s, size=%d, get_mask=%lx, set_mask=%lx, invert_mask=%lx\n",
5041 array_info->chip->label, array_info->size,
5042 *array_info->get_mask, *array_info->set_mask,
5043 *array_info->invert_mask);
5046 EXPORT_SYMBOL_GPL(gpiod_get_array);
5049 * gpiod_get_array_optional - obtain multiple GPIOs from a multi-index GPIO
5051 * @dev: GPIO consumer, can be NULL for system-global GPIOs
5052 * @con_id: function within the GPIO consumer
5053 * @flags: optional GPIO initialization flags
5055 * This is equivalent to gpiod_get_array(), except that when no GPIO was
5056 * assigned to the requested function it will return NULL.
5058 struct gpio_descs *__must_check gpiod_get_array_optional(struct device *dev,
5060 enum gpiod_flags flags)
5062 struct gpio_descs *descs;
5064 descs = gpiod_get_array(dev, con_id, flags);
5065 if (IS_ERR(descs) && (PTR_ERR(descs) == -ENOENT))
5070 EXPORT_SYMBOL_GPL(gpiod_get_array_optional);
5073 * gpiod_put - dispose of a GPIO descriptor
5074 * @desc: GPIO descriptor to dispose of
5076 * No descriptor can be used after gpiod_put() has been called on it.
5078 void gpiod_put(struct gpio_desc *desc)
5083 EXPORT_SYMBOL_GPL(gpiod_put);
5086 * gpiod_put_array - dispose of multiple GPIO descriptors
5087 * @descs: struct gpio_descs containing an array of descriptors
5089 void gpiod_put_array(struct gpio_descs *descs)
5093 for (i = 0; i < descs->ndescs; i++)
5094 gpiod_put(descs->desc[i]);
5098 EXPORT_SYMBOL_GPL(gpiod_put_array);
5100 static int __init gpiolib_dev_init(void)
5104 /* Register GPIO sysfs bus */
5105 ret = bus_register(&gpio_bus_type);
5107 pr_err("gpiolib: could not register GPIO bus type\n");
5111 ret = alloc_chrdev_region(&gpio_devt, 0, GPIO_DEV_MAX, GPIOCHIP_NAME);
5113 pr_err("gpiolib: failed to allocate char dev region\n");
5114 bus_unregister(&gpio_bus_type);
5116 gpiolib_initialized = true;
5117 gpiochip_setup_devs();
5121 core_initcall(gpiolib_dev_init);
5123 #ifdef CONFIG_DEBUG_FS
5125 static void gpiolib_dbg_show(struct seq_file *s, struct gpio_device *gdev)
5128 struct gpio_chip *chip = gdev->chip;
5129 unsigned gpio = gdev->base;
5130 struct gpio_desc *gdesc = &gdev->descs[0];
5135 for (i = 0; i < gdev->ngpio; i++, gpio++, gdesc++) {
5136 if (!test_bit(FLAG_REQUESTED, &gdesc->flags)) {
5138 seq_printf(s, " gpio-%-3d (%-20.20s)\n",
5144 gpiod_get_direction(gdesc);
5145 is_out = test_bit(FLAG_IS_OUT, &gdesc->flags);
5146 is_irq = test_bit(FLAG_USED_AS_IRQ, &gdesc->flags);
5147 active_low = test_bit(FLAG_ACTIVE_LOW, &gdesc->flags);
5148 seq_printf(s, " gpio-%-3d (%-20.20s|%-20.20s) %s %s %s%s",
5149 gpio, gdesc->name ? gdesc->name : "", gdesc->label,
5150 is_out ? "out" : "in ",
5151 chip->get ? (chip->get(chip, i) ? "hi" : "lo") : "? ",
5152 is_irq ? "IRQ " : "",
5153 active_low ? "ACTIVE LOW" : "");
5154 seq_printf(s, "\n");
5158 static void *gpiolib_seq_start(struct seq_file *s, loff_t *pos)
5160 unsigned long flags;
5161 struct gpio_device *gdev = NULL;
5162 loff_t index = *pos;
5166 spin_lock_irqsave(&gpio_lock, flags);
5167 list_for_each_entry(gdev, &gpio_devices, list)
5169 spin_unlock_irqrestore(&gpio_lock, flags);
5172 spin_unlock_irqrestore(&gpio_lock, flags);
5177 static void *gpiolib_seq_next(struct seq_file *s, void *v, loff_t *pos)
5179 unsigned long flags;
5180 struct gpio_device *gdev = v;
5183 spin_lock_irqsave(&gpio_lock, flags);
5184 if (list_is_last(&gdev->list, &gpio_devices))
5187 ret = list_entry(gdev->list.next, struct gpio_device, list);
5188 spin_unlock_irqrestore(&gpio_lock, flags);
5196 static void gpiolib_seq_stop(struct seq_file *s, void *v)
5200 static int gpiolib_seq_show(struct seq_file *s, void *v)
5202 struct gpio_device *gdev = v;
5203 struct gpio_chip *chip = gdev->chip;
5204 struct device *parent;
5207 seq_printf(s, "%s%s: (dangling chip)", (char *)s->private,
5208 dev_name(&gdev->dev));
5212 seq_printf(s, "%s%s: GPIOs %d-%d", (char *)s->private,
5213 dev_name(&gdev->dev),
5214 gdev->base, gdev->base + gdev->ngpio - 1);
5215 parent = chip->parent;
5217 seq_printf(s, ", parent: %s/%s",
5218 parent->bus ? parent->bus->name : "no-bus",
5221 seq_printf(s, ", %s", chip->label);
5222 if (chip->can_sleep)
5223 seq_printf(s, ", can sleep");
5224 seq_printf(s, ":\n");
5227 chip->dbg_show(s, chip);
5229 gpiolib_dbg_show(s, gdev);
5234 static const struct seq_operations gpiolib_seq_ops = {
5235 .start = gpiolib_seq_start,
5236 .next = gpiolib_seq_next,
5237 .stop = gpiolib_seq_stop,
5238 .show = gpiolib_seq_show,
5241 static int gpiolib_open(struct inode *inode, struct file *file)
5243 return seq_open(file, &gpiolib_seq_ops);
5246 static const struct file_operations gpiolib_operations = {
5247 .owner = THIS_MODULE,
5248 .open = gpiolib_open,
5250 .llseek = seq_lseek,
5251 .release = seq_release,
5254 static int __init gpiolib_debugfs_init(void)
5256 /* /sys/kernel/debug/gpio */
5257 debugfs_create_file("gpio", S_IFREG | S_IRUGO, NULL, NULL,
5258 &gpiolib_operations);
5261 subsys_initcall(gpiolib_debugfs_init);
5263 #endif /* DEBUG_FS */