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_valid_mask(struct gpio_chip *gpiochip);
90 static void gpiochip_irqchip_free_valid_mask(struct gpio_chip *gpiochip);
92 static bool gpiolib_initialized;
94 static inline void desc_set_label(struct gpio_desc *d, const char *label)
100 * gpio_to_desc - Convert a GPIO number to its descriptor
101 * @gpio: global GPIO number
104 * The GPIO descriptor associated with the given GPIO, or %NULL if no GPIO
105 * with the given number exists in the system.
107 struct gpio_desc *gpio_to_desc(unsigned gpio)
109 struct gpio_device *gdev;
112 spin_lock_irqsave(&gpio_lock, flags);
114 list_for_each_entry(gdev, &gpio_devices, list) {
115 if (gdev->base <= gpio &&
116 gdev->base + gdev->ngpio > gpio) {
117 spin_unlock_irqrestore(&gpio_lock, flags);
118 return &gdev->descs[gpio - gdev->base];
122 spin_unlock_irqrestore(&gpio_lock, flags);
124 if (!gpio_is_valid(gpio))
125 WARN(1, "invalid GPIO %d\n", gpio);
129 EXPORT_SYMBOL_GPL(gpio_to_desc);
132 * gpiochip_get_desc - get the GPIO descriptor corresponding to the given
133 * hardware number for this chip
135 * @hwnum: hardware number of the GPIO for this chip
138 * A pointer to the GPIO descriptor or %ERR_PTR(-EINVAL) if no GPIO exists
139 * in the given chip for the specified hardware number.
141 struct gpio_desc *gpiochip_get_desc(struct gpio_chip *chip,
144 struct gpio_device *gdev = chip->gpiodev;
146 if (hwnum >= gdev->ngpio)
147 return ERR_PTR(-EINVAL);
149 return &gdev->descs[hwnum];
153 * desc_to_gpio - convert a GPIO descriptor to the integer namespace
154 * @desc: GPIO descriptor
156 * This should disappear in the future but is needed since we still
157 * use GPIO numbers for error messages and sysfs nodes.
160 * The global GPIO number for the GPIO specified by its descriptor.
162 int desc_to_gpio(const struct gpio_desc *desc)
164 return desc->gdev->base + (desc - &desc->gdev->descs[0]);
166 EXPORT_SYMBOL_GPL(desc_to_gpio);
170 * gpiod_to_chip - Return the GPIO chip to which a GPIO descriptor belongs
171 * @desc: descriptor to return the chip of
173 struct gpio_chip *gpiod_to_chip(const struct gpio_desc *desc)
175 if (!desc || !desc->gdev)
177 return desc->gdev->chip;
179 EXPORT_SYMBOL_GPL(gpiod_to_chip);
181 /* dynamic allocation of GPIOs, e.g. on a hotplugged device */
182 static int gpiochip_find_base(int ngpio)
184 struct gpio_device *gdev;
185 int base = ARCH_NR_GPIOS - ngpio;
187 list_for_each_entry_reverse(gdev, &gpio_devices, list) {
188 /* found a free space? */
189 if (gdev->base + gdev->ngpio <= base)
192 /* nope, check the space right before the chip */
193 base = gdev->base - ngpio;
196 if (gpio_is_valid(base)) {
197 pr_debug("%s: found new base at %d\n", __func__, base);
200 pr_err("%s: cannot find free range\n", __func__);
206 * gpiod_get_direction - return the current direction of a GPIO
207 * @desc: GPIO to get the direction of
209 * Returns 0 for output, 1 for input, or an error code in case of error.
211 * This function may sleep if gpiod_cansleep() is true.
213 int gpiod_get_direction(struct gpio_desc *desc)
215 struct gpio_chip *chip;
219 chip = gpiod_to_chip(desc);
220 offset = gpio_chip_hwgpio(desc);
222 if (!chip->get_direction)
225 ret = chip->get_direction(chip, offset);
227 /* GPIOF_DIR_IN, or other positive */
229 clear_bit(FLAG_IS_OUT, &desc->flags);
233 set_bit(FLAG_IS_OUT, &desc->flags);
237 EXPORT_SYMBOL_GPL(gpiod_get_direction);
240 * Add a new chip to the global chips list, keeping the list of chips sorted
241 * by range(means [base, base + ngpio - 1]) order.
243 * Return -EBUSY if the new chip overlaps with some other chip's integer
246 static int gpiodev_add_to_list(struct gpio_device *gdev)
248 struct gpio_device *prev, *next;
250 if (list_empty(&gpio_devices)) {
251 /* initial entry in list */
252 list_add_tail(&gdev->list, &gpio_devices);
256 next = list_entry(gpio_devices.next, struct gpio_device, list);
257 if (gdev->base + gdev->ngpio <= next->base) {
258 /* add before first entry */
259 list_add(&gdev->list, &gpio_devices);
263 prev = list_entry(gpio_devices.prev, struct gpio_device, list);
264 if (prev->base + prev->ngpio <= gdev->base) {
265 /* add behind last entry */
266 list_add_tail(&gdev->list, &gpio_devices);
270 list_for_each_entry_safe(prev, next, &gpio_devices, list) {
271 /* at the end of the list */
272 if (&next->list == &gpio_devices)
275 /* add between prev and next */
276 if (prev->base + prev->ngpio <= gdev->base
277 && gdev->base + gdev->ngpio <= next->base) {
278 list_add(&gdev->list, &prev->list);
283 dev_err(&gdev->dev, "GPIO integer space overlap, cannot add chip\n");
288 * Convert a GPIO name to its descriptor
290 static struct gpio_desc *gpio_name_to_desc(const char * const name)
292 struct gpio_device *gdev;
295 spin_lock_irqsave(&gpio_lock, flags);
297 list_for_each_entry(gdev, &gpio_devices, list) {
300 for (i = 0; i != gdev->ngpio; ++i) {
301 struct gpio_desc *desc = &gdev->descs[i];
303 if (!desc->name || !name)
306 if (!strcmp(desc->name, name)) {
307 spin_unlock_irqrestore(&gpio_lock, flags);
313 spin_unlock_irqrestore(&gpio_lock, flags);
319 * Takes the names from gc->names and checks if they are all unique. If they
320 * are, they are assigned to their gpio descriptors.
322 * Warning if one of the names is already used for a different GPIO.
324 static int gpiochip_set_desc_names(struct gpio_chip *gc)
326 struct gpio_device *gdev = gc->gpiodev;
332 /* First check all names if they are unique */
333 for (i = 0; i != gc->ngpio; ++i) {
334 struct gpio_desc *gpio;
336 gpio = gpio_name_to_desc(gc->names[i]);
339 "Detected name collision for GPIO name '%s'\n",
343 /* Then add all names to the GPIO descriptors */
344 for (i = 0; i != gc->ngpio; ++i)
345 gdev->descs[i].name = gc->names[i];
350 static unsigned long *gpiochip_allocate_mask(struct gpio_chip *chip)
354 p = bitmap_alloc(chip->ngpio, GFP_KERNEL);
358 /* Assume by default all GPIOs are valid */
359 bitmap_fill(p, chip->ngpio);
364 static int gpiochip_alloc_valid_mask(struct gpio_chip *gc)
366 if (!(of_gpio_need_valid_mask(gc) || gc->init_valid_mask))
369 gc->valid_mask = gpiochip_allocate_mask(gc);
376 static int gpiochip_init_valid_mask(struct gpio_chip *gc)
378 if (gc->init_valid_mask)
379 return gc->init_valid_mask(gc,
386 static void gpiochip_free_valid_mask(struct gpio_chip *gpiochip)
388 bitmap_free(gpiochip->valid_mask);
389 gpiochip->valid_mask = NULL;
392 bool gpiochip_line_is_valid(const struct gpio_chip *gpiochip,
395 /* No mask means all valid */
396 if (likely(!gpiochip->valid_mask))
398 return test_bit(offset, gpiochip->valid_mask);
400 EXPORT_SYMBOL_GPL(gpiochip_line_is_valid);
403 * GPIO line handle management
407 * struct linehandle_state - contains the state of a userspace handle
408 * @gdev: the GPIO device the handle pertains to
409 * @label: consumer label used to tag descriptors
410 * @descs: the GPIO descriptors held by this handle
411 * @numdescs: the number of descriptors held in the descs array
413 struct linehandle_state {
414 struct gpio_device *gdev;
416 struct gpio_desc *descs[GPIOHANDLES_MAX];
420 #define GPIOHANDLE_REQUEST_VALID_FLAGS \
421 (GPIOHANDLE_REQUEST_INPUT | \
422 GPIOHANDLE_REQUEST_OUTPUT | \
423 GPIOHANDLE_REQUEST_ACTIVE_LOW | \
424 GPIOHANDLE_REQUEST_OPEN_DRAIN | \
425 GPIOHANDLE_REQUEST_OPEN_SOURCE)
427 static long linehandle_ioctl(struct file *filep, unsigned int cmd,
430 struct linehandle_state *lh = filep->private_data;
431 void __user *ip = (void __user *)arg;
432 struct gpiohandle_data ghd;
433 DECLARE_BITMAP(vals, GPIOHANDLES_MAX);
436 if (cmd == GPIOHANDLE_GET_LINE_VALUES_IOCTL) {
437 /* NOTE: It's ok to read values of output lines. */
438 int ret = gpiod_get_array_value_complex(false,
447 memset(&ghd, 0, sizeof(ghd));
448 for (i = 0; i < lh->numdescs; i++)
449 ghd.values[i] = test_bit(i, vals);
451 if (copy_to_user(ip, &ghd, sizeof(ghd)))
455 } else if (cmd == GPIOHANDLE_SET_LINE_VALUES_IOCTL) {
457 * All line descriptors were created at once with the same
458 * flags so just check if the first one is really output.
460 if (!test_bit(FLAG_IS_OUT, &lh->descs[0]->flags))
463 if (copy_from_user(&ghd, ip, sizeof(ghd)))
466 /* Clamp all values to [0,1] */
467 for (i = 0; i < lh->numdescs; i++)
468 __assign_bit(i, vals, ghd.values[i]);
470 /* Reuse the array setting function */
471 return gpiod_set_array_value_complex(false,
482 static long linehandle_ioctl_compat(struct file *filep, unsigned int cmd,
485 return linehandle_ioctl(filep, cmd, (unsigned long)compat_ptr(arg));
489 static int linehandle_release(struct inode *inode, struct file *filep)
491 struct linehandle_state *lh = filep->private_data;
492 struct gpio_device *gdev = lh->gdev;
495 for (i = 0; i < lh->numdescs; i++)
496 gpiod_free(lh->descs[i]);
499 put_device(&gdev->dev);
503 static const struct file_operations linehandle_fileops = {
504 .release = linehandle_release,
505 .owner = THIS_MODULE,
506 .llseek = noop_llseek,
507 .unlocked_ioctl = linehandle_ioctl,
509 .compat_ioctl = linehandle_ioctl_compat,
513 static int linehandle_create(struct gpio_device *gdev, void __user *ip)
515 struct gpiohandle_request handlereq;
516 struct linehandle_state *lh;
518 int fd, i, count = 0, ret;
521 if (copy_from_user(&handlereq, ip, sizeof(handlereq)))
523 if ((handlereq.lines == 0) || (handlereq.lines > GPIOHANDLES_MAX))
526 lflags = handlereq.flags;
528 /* Return an error if an unknown flag is set */
529 if (lflags & ~GPIOHANDLE_REQUEST_VALID_FLAGS)
533 * Do not allow both INPUT & OUTPUT flags to be set as they are
536 if ((lflags & GPIOHANDLE_REQUEST_INPUT) &&
537 (lflags & GPIOHANDLE_REQUEST_OUTPUT))
541 * Do not allow OPEN_SOURCE & OPEN_DRAIN flags in a single request. If
542 * the hardware actually supports enabling both at the same time the
543 * electrical result would be disastrous.
545 if ((lflags & GPIOHANDLE_REQUEST_OPEN_DRAIN) &&
546 (lflags & GPIOHANDLE_REQUEST_OPEN_SOURCE))
549 /* OPEN_DRAIN and OPEN_SOURCE flags only make sense for output mode. */
550 if (!(lflags & GPIOHANDLE_REQUEST_OUTPUT) &&
551 ((lflags & GPIOHANDLE_REQUEST_OPEN_DRAIN) ||
552 (lflags & GPIOHANDLE_REQUEST_OPEN_SOURCE)))
555 lh = kzalloc(sizeof(*lh), GFP_KERNEL);
559 get_device(&gdev->dev);
561 /* Make sure this is terminated */
562 handlereq.consumer_label[sizeof(handlereq.consumer_label)-1] = '\0';
563 if (strlen(handlereq.consumer_label)) {
564 lh->label = kstrdup(handlereq.consumer_label,
572 /* Request each GPIO */
573 for (i = 0; i < handlereq.lines; i++) {
574 u32 offset = handlereq.lineoffsets[i];
575 struct gpio_desc *desc;
577 if (offset >= gdev->ngpio) {
582 desc = &gdev->descs[offset];
583 ret = gpiod_request(desc, lh->label);
589 if (lflags & GPIOHANDLE_REQUEST_ACTIVE_LOW)
590 set_bit(FLAG_ACTIVE_LOW, &desc->flags);
591 if (lflags & GPIOHANDLE_REQUEST_OPEN_DRAIN)
592 set_bit(FLAG_OPEN_DRAIN, &desc->flags);
593 if (lflags & GPIOHANDLE_REQUEST_OPEN_SOURCE)
594 set_bit(FLAG_OPEN_SOURCE, &desc->flags);
596 ret = gpiod_set_transitory(desc, false);
601 * Lines have to be requested explicitly for input
602 * or output, else the line will be treated "as is".
604 if (lflags & GPIOHANDLE_REQUEST_OUTPUT) {
605 int val = !!handlereq.default_values[i];
607 ret = gpiod_direction_output(desc, val);
610 } else if (lflags & GPIOHANDLE_REQUEST_INPUT) {
611 ret = gpiod_direction_input(desc);
615 dev_dbg(&gdev->dev, "registered chardev handle for line %d\n",
618 /* Let i point at the last handle */
620 lh->numdescs = handlereq.lines;
622 fd = get_unused_fd_flags(O_RDONLY | O_CLOEXEC);
628 file = anon_inode_getfile("gpio-linehandle",
631 O_RDONLY | O_CLOEXEC);
634 goto out_put_unused_fd;
638 if (copy_to_user(ip, &handlereq, sizeof(handlereq))) {
640 * fput() will trigger the release() callback, so do not go onto
641 * the regular error cleanup path here.
648 fd_install(fd, file);
650 dev_dbg(&gdev->dev, "registered chardev handle for %d lines\n",
658 for (i = 0; i < count; i++)
659 gpiod_free(lh->descs[i]);
663 put_device(&gdev->dev);
668 * GPIO line event management
672 * struct lineevent_state - contains the state of a userspace event
673 * @gdev: the GPIO device the event pertains to
674 * @label: consumer label used to tag descriptors
675 * @desc: the GPIO descriptor held by this event
676 * @eflags: the event flags this line was requested with
677 * @irq: the interrupt that trigger in response to events on this GPIO
678 * @wait: wait queue that handles blocking reads of events
679 * @events: KFIFO for the GPIO events
680 * @read_lock: mutex lock to protect reads from colliding with adding
681 * new events to the FIFO
682 * @timestamp: cache for the timestamp storing it between hardirq
683 * and IRQ thread, used to bring the timestamp close to the actual
686 struct lineevent_state {
687 struct gpio_device *gdev;
689 struct gpio_desc *desc;
692 wait_queue_head_t wait;
693 DECLARE_KFIFO(events, struct gpioevent_data, 16);
694 struct mutex read_lock;
698 #define GPIOEVENT_REQUEST_VALID_FLAGS \
699 (GPIOEVENT_REQUEST_RISING_EDGE | \
700 GPIOEVENT_REQUEST_FALLING_EDGE)
702 static __poll_t lineevent_poll(struct file *filep,
703 struct poll_table_struct *wait)
705 struct lineevent_state *le = filep->private_data;
708 poll_wait(filep, &le->wait, wait);
710 if (!kfifo_is_empty(&le->events))
711 events = EPOLLIN | EPOLLRDNORM;
717 static ssize_t lineevent_read(struct file *filep,
722 struct lineevent_state *le = filep->private_data;
726 if (count < sizeof(struct gpioevent_data))
730 if (kfifo_is_empty(&le->events)) {
731 if (filep->f_flags & O_NONBLOCK)
734 ret = wait_event_interruptible(le->wait,
735 !kfifo_is_empty(&le->events));
740 if (mutex_lock_interruptible(&le->read_lock))
742 ret = kfifo_to_user(&le->events, buf, count, &copied);
743 mutex_unlock(&le->read_lock);
749 * If we couldn't read anything from the fifo (a different
750 * thread might have been faster) we either return -EAGAIN if
751 * the file descriptor is non-blocking, otherwise we go back to
752 * sleep and wait for more data to arrive.
754 if (copied == 0 && (filep->f_flags & O_NONBLOCK))
757 } while (copied == 0);
762 static int lineevent_release(struct inode *inode, struct file *filep)
764 struct lineevent_state *le = filep->private_data;
765 struct gpio_device *gdev = le->gdev;
767 free_irq(le->irq, le);
768 gpiod_free(le->desc);
771 put_device(&gdev->dev);
775 static long lineevent_ioctl(struct file *filep, unsigned int cmd,
778 struct lineevent_state *le = filep->private_data;
779 void __user *ip = (void __user *)arg;
780 struct gpiohandle_data ghd;
783 * We can get the value for an event line but not set it,
784 * because it is input by definition.
786 if (cmd == GPIOHANDLE_GET_LINE_VALUES_IOCTL) {
789 memset(&ghd, 0, sizeof(ghd));
791 val = gpiod_get_value_cansleep(le->desc);
796 if (copy_to_user(ip, &ghd, sizeof(ghd)))
805 static long lineevent_ioctl_compat(struct file *filep, unsigned int cmd,
808 return lineevent_ioctl(filep, cmd, (unsigned long)compat_ptr(arg));
812 static const struct file_operations lineevent_fileops = {
813 .release = lineevent_release,
814 .read = lineevent_read,
815 .poll = lineevent_poll,
816 .owner = THIS_MODULE,
817 .llseek = noop_llseek,
818 .unlocked_ioctl = lineevent_ioctl,
820 .compat_ioctl = lineevent_ioctl_compat,
824 static irqreturn_t lineevent_irq_thread(int irq, void *p)
826 struct lineevent_state *le = p;
827 struct gpioevent_data ge;
830 /* Do not leak kernel stack to userspace */
831 memset(&ge, 0, sizeof(ge));
834 * We may be running from a nested threaded interrupt in which case
835 * we didn't get the timestamp from lineevent_irq_handler().
838 ge.timestamp = ktime_get_real_ns();
840 ge.timestamp = le->timestamp;
842 if (le->eflags & GPIOEVENT_REQUEST_RISING_EDGE
843 && le->eflags & GPIOEVENT_REQUEST_FALLING_EDGE) {
844 int level = gpiod_get_value_cansleep(le->desc);
846 /* Emit low-to-high event */
847 ge.id = GPIOEVENT_EVENT_RISING_EDGE;
849 /* Emit high-to-low event */
850 ge.id = GPIOEVENT_EVENT_FALLING_EDGE;
851 } else if (le->eflags & GPIOEVENT_REQUEST_RISING_EDGE) {
852 /* Emit low-to-high event */
853 ge.id = GPIOEVENT_EVENT_RISING_EDGE;
854 } else if (le->eflags & GPIOEVENT_REQUEST_FALLING_EDGE) {
855 /* Emit high-to-low event */
856 ge.id = GPIOEVENT_EVENT_FALLING_EDGE;
861 ret = kfifo_put(&le->events, ge);
863 wake_up_poll(&le->wait, EPOLLIN);
868 static irqreturn_t lineevent_irq_handler(int irq, void *p)
870 struct lineevent_state *le = p;
873 * Just store the timestamp in hardirq context so we get it as
874 * close in time as possible to the actual event.
876 le->timestamp = ktime_get_real_ns();
878 return IRQ_WAKE_THREAD;
881 static int lineevent_create(struct gpio_device *gdev, void __user *ip)
883 struct gpioevent_request eventreq;
884 struct lineevent_state *le;
885 struct gpio_desc *desc;
894 if (copy_from_user(&eventreq, ip, sizeof(eventreq)))
897 le = kzalloc(sizeof(*le), GFP_KERNEL);
901 get_device(&gdev->dev);
903 /* Make sure this is terminated */
904 eventreq.consumer_label[sizeof(eventreq.consumer_label)-1] = '\0';
905 if (strlen(eventreq.consumer_label)) {
906 le->label = kstrdup(eventreq.consumer_label,
914 offset = eventreq.lineoffset;
915 lflags = eventreq.handleflags;
916 eflags = eventreq.eventflags;
918 if (offset >= gdev->ngpio) {
923 /* Return an error if a unknown flag is set */
924 if ((lflags & ~GPIOHANDLE_REQUEST_VALID_FLAGS) ||
925 (eflags & ~GPIOEVENT_REQUEST_VALID_FLAGS)) {
930 /* This is just wrong: we don't look for events on output lines */
931 if ((lflags & GPIOHANDLE_REQUEST_OUTPUT) ||
932 (lflags & GPIOHANDLE_REQUEST_OPEN_DRAIN) ||
933 (lflags & GPIOHANDLE_REQUEST_OPEN_SOURCE)) {
938 desc = &gdev->descs[offset];
939 ret = gpiod_request(desc, le->label);
945 if (lflags & GPIOHANDLE_REQUEST_ACTIVE_LOW)
946 set_bit(FLAG_ACTIVE_LOW, &desc->flags);
948 ret = gpiod_direction_input(desc);
952 le->irq = gpiod_to_irq(desc);
958 if (eflags & GPIOEVENT_REQUEST_RISING_EDGE)
959 irqflags |= test_bit(FLAG_ACTIVE_LOW, &desc->flags) ?
960 IRQF_TRIGGER_FALLING : IRQF_TRIGGER_RISING;
961 if (eflags & GPIOEVENT_REQUEST_FALLING_EDGE)
962 irqflags |= test_bit(FLAG_ACTIVE_LOW, &desc->flags) ?
963 IRQF_TRIGGER_RISING : IRQF_TRIGGER_FALLING;
964 irqflags |= IRQF_ONESHOT;
966 INIT_KFIFO(le->events);
967 init_waitqueue_head(&le->wait);
968 mutex_init(&le->read_lock);
970 /* Request a thread to read the events */
971 ret = request_threaded_irq(le->irq,
972 lineevent_irq_handler,
973 lineevent_irq_thread,
980 fd = get_unused_fd_flags(O_RDONLY | O_CLOEXEC);
986 file = anon_inode_getfile("gpio-event",
989 O_RDONLY | O_CLOEXEC);
992 goto out_put_unused_fd;
996 if (copy_to_user(ip, &eventreq, sizeof(eventreq))) {
998 * fput() will trigger the release() callback, so do not go onto
999 * the regular error cleanup path here.
1006 fd_install(fd, file);
1013 free_irq(le->irq, le);
1015 gpiod_free(le->desc);
1020 put_device(&gdev->dev);
1025 * gpio_ioctl() - ioctl handler for the GPIO chardev
1027 static long gpio_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
1029 struct gpio_device *gdev = filp->private_data;
1030 struct gpio_chip *chip = gdev->chip;
1031 void __user *ip = (void __user *)arg;
1033 /* We fail any subsequent ioctl():s when the chip is gone */
1037 /* Fill in the struct and pass to userspace */
1038 if (cmd == GPIO_GET_CHIPINFO_IOCTL) {
1039 struct gpiochip_info chipinfo;
1041 memset(&chipinfo, 0, sizeof(chipinfo));
1043 strncpy(chipinfo.name, dev_name(&gdev->dev),
1044 sizeof(chipinfo.name));
1045 chipinfo.name[sizeof(chipinfo.name)-1] = '\0';
1046 strncpy(chipinfo.label, gdev->label,
1047 sizeof(chipinfo.label));
1048 chipinfo.label[sizeof(chipinfo.label)-1] = '\0';
1049 chipinfo.lines = gdev->ngpio;
1050 if (copy_to_user(ip, &chipinfo, sizeof(chipinfo)))
1053 } else if (cmd == GPIO_GET_LINEINFO_IOCTL) {
1054 struct gpioline_info lineinfo;
1055 struct gpio_desc *desc;
1057 if (copy_from_user(&lineinfo, ip, sizeof(lineinfo)))
1059 if (lineinfo.line_offset >= gdev->ngpio)
1062 desc = &gdev->descs[lineinfo.line_offset];
1064 strncpy(lineinfo.name, desc->name,
1065 sizeof(lineinfo.name));
1066 lineinfo.name[sizeof(lineinfo.name)-1] = '\0';
1068 lineinfo.name[0] = '\0';
1071 strncpy(lineinfo.consumer, desc->label,
1072 sizeof(lineinfo.consumer));
1073 lineinfo.consumer[sizeof(lineinfo.consumer)-1] = '\0';
1075 lineinfo.consumer[0] = '\0';
1079 * Userspace only need to know that the kernel is using
1080 * this GPIO so it can't use it.
1083 if (test_bit(FLAG_REQUESTED, &desc->flags) ||
1084 test_bit(FLAG_IS_HOGGED, &desc->flags) ||
1085 test_bit(FLAG_USED_AS_IRQ, &desc->flags) ||
1086 test_bit(FLAG_EXPORT, &desc->flags) ||
1087 test_bit(FLAG_SYSFS, &desc->flags))
1088 lineinfo.flags |= GPIOLINE_FLAG_KERNEL;
1089 if (test_bit(FLAG_IS_OUT, &desc->flags))
1090 lineinfo.flags |= GPIOLINE_FLAG_IS_OUT;
1091 if (test_bit(FLAG_ACTIVE_LOW, &desc->flags))
1092 lineinfo.flags |= GPIOLINE_FLAG_ACTIVE_LOW;
1093 if (test_bit(FLAG_OPEN_DRAIN, &desc->flags))
1094 lineinfo.flags |= (GPIOLINE_FLAG_OPEN_DRAIN |
1095 GPIOLINE_FLAG_IS_OUT);
1096 if (test_bit(FLAG_OPEN_SOURCE, &desc->flags))
1097 lineinfo.flags |= (GPIOLINE_FLAG_OPEN_SOURCE |
1098 GPIOLINE_FLAG_IS_OUT);
1100 if (copy_to_user(ip, &lineinfo, sizeof(lineinfo)))
1103 } else if (cmd == GPIO_GET_LINEHANDLE_IOCTL) {
1104 return linehandle_create(gdev, ip);
1105 } else if (cmd == GPIO_GET_LINEEVENT_IOCTL) {
1106 return lineevent_create(gdev, ip);
1111 #ifdef CONFIG_COMPAT
1112 static long gpio_ioctl_compat(struct file *filp, unsigned int cmd,
1115 return gpio_ioctl(filp, cmd, (unsigned long)compat_ptr(arg));
1120 * gpio_chrdev_open() - open the chardev for ioctl operations
1121 * @inode: inode for this chardev
1122 * @filp: file struct for storing private data
1123 * Returns 0 on success
1125 static int gpio_chrdev_open(struct inode *inode, struct file *filp)
1127 struct gpio_device *gdev = container_of(inode->i_cdev,
1128 struct gpio_device, chrdev);
1130 /* Fail on open if the backing gpiochip is gone */
1133 get_device(&gdev->dev);
1134 filp->private_data = gdev;
1136 return nonseekable_open(inode, filp);
1140 * gpio_chrdev_release() - close chardev after ioctl operations
1141 * @inode: inode for this chardev
1142 * @filp: file struct for storing private data
1143 * Returns 0 on success
1145 static int gpio_chrdev_release(struct inode *inode, struct file *filp)
1147 struct gpio_device *gdev = container_of(inode->i_cdev,
1148 struct gpio_device, chrdev);
1150 put_device(&gdev->dev);
1155 static const struct file_operations gpio_fileops = {
1156 .release = gpio_chrdev_release,
1157 .open = gpio_chrdev_open,
1158 .owner = THIS_MODULE,
1159 .llseek = no_llseek,
1160 .unlocked_ioctl = gpio_ioctl,
1161 #ifdef CONFIG_COMPAT
1162 .compat_ioctl = gpio_ioctl_compat,
1166 static void gpiodevice_release(struct device *dev)
1168 struct gpio_device *gdev = dev_get_drvdata(dev);
1170 list_del(&gdev->list);
1171 ida_simple_remove(&gpio_ida, gdev->id);
1172 kfree_const(gdev->label);
1177 static int gpiochip_setup_dev(struct gpio_device *gdev)
1181 cdev_init(&gdev->chrdev, &gpio_fileops);
1182 gdev->chrdev.owner = THIS_MODULE;
1183 gdev->dev.devt = MKDEV(MAJOR(gpio_devt), gdev->id);
1185 ret = cdev_device_add(&gdev->chrdev, &gdev->dev);
1189 chip_dbg(gdev->chip, "added GPIO chardev (%d:%d)\n",
1190 MAJOR(gpio_devt), gdev->id);
1192 ret = gpiochip_sysfs_register(gdev);
1194 goto err_remove_device;
1196 /* From this point, the .release() function cleans up gpio_device */
1197 gdev->dev.release = gpiodevice_release;
1198 pr_debug("%s: registered GPIOs %d to %d on device: %s (%s)\n",
1199 __func__, gdev->base, gdev->base + gdev->ngpio - 1,
1200 dev_name(&gdev->dev), gdev->chip->label ? : "generic");
1205 cdev_device_del(&gdev->chrdev, &gdev->dev);
1209 static void gpiochip_machine_hog(struct gpio_chip *chip, struct gpiod_hog *hog)
1211 struct gpio_desc *desc;
1214 desc = gpiochip_get_desc(chip, hog->chip_hwnum);
1216 pr_err("%s: unable to get GPIO desc: %ld\n",
1217 __func__, PTR_ERR(desc));
1221 if (test_bit(FLAG_IS_HOGGED, &desc->flags))
1224 rv = gpiod_hog(desc, hog->line_name, hog->lflags, hog->dflags);
1226 pr_err("%s: unable to hog GPIO line (%s:%u): %d\n",
1227 __func__, chip->label, hog->chip_hwnum, rv);
1230 static void machine_gpiochip_add(struct gpio_chip *chip)
1232 struct gpiod_hog *hog;
1234 mutex_lock(&gpio_machine_hogs_mutex);
1236 list_for_each_entry(hog, &gpio_machine_hogs, list) {
1237 if (!strcmp(chip->label, hog->chip_label))
1238 gpiochip_machine_hog(chip, hog);
1241 mutex_unlock(&gpio_machine_hogs_mutex);
1244 static void gpiochip_setup_devs(void)
1246 struct gpio_device *gdev;
1249 list_for_each_entry(gdev, &gpio_devices, list) {
1250 ret = gpiochip_setup_dev(gdev);
1252 pr_err("%s: Failed to initialize gpio device (%d)\n",
1253 dev_name(&gdev->dev), ret);
1257 int gpiochip_add_data_with_key(struct gpio_chip *chip, void *data,
1258 struct lock_class_key *lock_key,
1259 struct lock_class_key *request_key)
1261 unsigned long flags;
1264 int base = chip->base;
1265 struct gpio_device *gdev;
1268 * First: allocate and populate the internal stat container, and
1269 * set up the struct device.
1271 gdev = kzalloc(sizeof(*gdev), GFP_KERNEL);
1274 gdev->dev.bus = &gpio_bus_type;
1276 chip->gpiodev = gdev;
1278 gdev->dev.parent = chip->parent;
1279 gdev->dev.of_node = chip->parent->of_node;
1282 #ifdef CONFIG_OF_GPIO
1283 /* If the gpiochip has an assigned OF node this takes precedence */
1285 gdev->dev.of_node = chip->of_node;
1287 chip->of_node = gdev->dev.of_node;
1290 gdev->id = ida_simple_get(&gpio_ida, 0, 0, GFP_KERNEL);
1295 dev_set_name(&gdev->dev, "gpiochip%d", gdev->id);
1296 device_initialize(&gdev->dev);
1297 dev_set_drvdata(&gdev->dev, gdev);
1298 if (chip->parent && chip->parent->driver)
1299 gdev->owner = chip->parent->driver->owner;
1300 else if (chip->owner)
1301 /* TODO: remove chip->owner */
1302 gdev->owner = chip->owner;
1304 gdev->owner = THIS_MODULE;
1306 gdev->descs = kcalloc(chip->ngpio, sizeof(gdev->descs[0]), GFP_KERNEL);
1312 if (chip->ngpio == 0) {
1313 chip_err(chip, "tried to insert a GPIO chip with zero lines\n");
1315 goto err_free_descs;
1318 if (chip->ngpio > FASTPATH_NGPIO)
1319 chip_warn(chip, "line cnt %u is greater than fast path cnt %u\n",
1320 chip->ngpio, FASTPATH_NGPIO);
1322 gdev->label = kstrdup_const(chip->label ?: "unknown", GFP_KERNEL);
1325 goto err_free_descs;
1328 gdev->ngpio = chip->ngpio;
1331 spin_lock_irqsave(&gpio_lock, flags);
1334 * TODO: this allocates a Linux GPIO number base in the global
1335 * GPIO numberspace for this chip. In the long run we want to
1336 * get *rid* of this numberspace and use only descriptors, but
1337 * it may be a pipe dream. It will not happen before we get rid
1338 * of the sysfs interface anyways.
1341 base = gpiochip_find_base(chip->ngpio);
1344 spin_unlock_irqrestore(&gpio_lock, flags);
1345 goto err_free_label;
1348 * TODO: it should not be necessary to reflect the assigned
1349 * base outside of the GPIO subsystem. Go over drivers and
1350 * see if anyone makes use of this, else drop this and assign
1357 ret = gpiodev_add_to_list(gdev);
1359 spin_unlock_irqrestore(&gpio_lock, flags);
1360 goto err_free_label;
1363 spin_unlock_irqrestore(&gpio_lock, flags);
1365 for (i = 0; i < chip->ngpio; i++)
1366 gdev->descs[i].gdev = gdev;
1368 #ifdef CONFIG_PINCTRL
1369 INIT_LIST_HEAD(&gdev->pin_ranges);
1372 ret = gpiochip_set_desc_names(chip);
1374 goto err_remove_from_list;
1376 ret = gpiochip_alloc_valid_mask(chip);
1378 goto err_remove_from_list;
1380 ret = of_gpiochip_add(chip);
1382 goto err_free_gpiochip_mask;
1384 ret = gpiochip_init_valid_mask(chip);
1386 goto err_remove_of_chip;
1388 for (i = 0; i < chip->ngpio; i++) {
1389 struct gpio_desc *desc = &gdev->descs[i];
1391 if (chip->get_direction && gpiochip_line_is_valid(chip, i)) {
1392 if (!chip->get_direction(chip, i))
1393 set_bit(FLAG_IS_OUT, &desc->flags);
1395 clear_bit(FLAG_IS_OUT, &desc->flags);
1397 if (!chip->direction_input)
1398 set_bit(FLAG_IS_OUT, &desc->flags);
1400 clear_bit(FLAG_IS_OUT, &desc->flags);
1404 acpi_gpiochip_add(chip);
1406 machine_gpiochip_add(chip);
1408 ret = gpiochip_irqchip_init_valid_mask(chip);
1410 goto err_remove_acpi_chip;
1412 ret = gpiochip_add_irqchip(chip, lock_key, request_key);
1414 goto err_remove_irqchip_mask;
1417 * By first adding the chardev, and then adding the device,
1418 * we get a device node entry in sysfs under
1419 * /sys/bus/gpio/devices/gpiochipN/dev that can be used for
1420 * coldplug of device nodes and other udev business.
1421 * We can do this only if gpiolib has been initialized.
1422 * Otherwise, defer until later.
1424 if (gpiolib_initialized) {
1425 ret = gpiochip_setup_dev(gdev);
1427 goto err_remove_irqchip;
1432 gpiochip_irqchip_remove(chip);
1433 err_remove_irqchip_mask:
1434 gpiochip_irqchip_free_valid_mask(chip);
1435 err_remove_acpi_chip:
1436 acpi_gpiochip_remove(chip);
1438 gpiochip_free_hogs(chip);
1439 of_gpiochip_remove(chip);
1440 err_free_gpiochip_mask:
1441 gpiochip_free_valid_mask(chip);
1442 err_remove_from_list:
1443 spin_lock_irqsave(&gpio_lock, flags);
1444 list_del(&gdev->list);
1445 spin_unlock_irqrestore(&gpio_lock, flags);
1447 kfree_const(gdev->label);
1451 ida_simple_remove(&gpio_ida, gdev->id);
1453 /* failures here can mean systems won't boot... */
1454 pr_err("%s: GPIOs %d..%d (%s) failed to register, %d\n", __func__,
1455 gdev->base, gdev->base + gdev->ngpio - 1,
1456 chip->label ? : "generic", ret);
1460 EXPORT_SYMBOL_GPL(gpiochip_add_data_with_key);
1463 * gpiochip_get_data() - get per-subdriver data for the chip
1467 * The per-subdriver data for the chip.
1469 void *gpiochip_get_data(struct gpio_chip *chip)
1471 return chip->gpiodev->data;
1473 EXPORT_SYMBOL_GPL(gpiochip_get_data);
1476 * gpiochip_remove() - unregister a gpio_chip
1477 * @chip: the chip to unregister
1479 * A gpio_chip with any GPIOs still requested may not be removed.
1481 void gpiochip_remove(struct gpio_chip *chip)
1483 struct gpio_device *gdev = chip->gpiodev;
1484 struct gpio_desc *desc;
1485 unsigned long flags;
1487 bool requested = false;
1489 /* FIXME: should the legacy sysfs handling be moved to gpio_device? */
1490 gpiochip_sysfs_unregister(gdev);
1491 gpiochip_free_hogs(chip);
1492 /* Numb the device, cancelling all outstanding operations */
1494 gpiochip_irqchip_remove(chip);
1495 acpi_gpiochip_remove(chip);
1496 gpiochip_remove_pin_ranges(chip);
1497 of_gpiochip_remove(chip);
1498 gpiochip_free_valid_mask(chip);
1500 * We accept no more calls into the driver from this point, so
1501 * NULL the driver data pointer
1505 spin_lock_irqsave(&gpio_lock, flags);
1506 for (i = 0; i < gdev->ngpio; i++) {
1507 desc = &gdev->descs[i];
1508 if (test_bit(FLAG_REQUESTED, &desc->flags))
1511 spin_unlock_irqrestore(&gpio_lock, flags);
1514 dev_crit(&gdev->dev,
1515 "REMOVING GPIOCHIP WITH GPIOS STILL REQUESTED\n");
1518 * The gpiochip side puts its use of the device to rest here:
1519 * if there are no userspace clients, the chardev and device will
1520 * be removed, else it will be dangling until the last user is
1523 cdev_device_del(&gdev->chrdev, &gdev->dev);
1524 put_device(&gdev->dev);
1526 EXPORT_SYMBOL_GPL(gpiochip_remove);
1528 static void devm_gpio_chip_release(struct device *dev, void *res)
1530 struct gpio_chip *chip = *(struct gpio_chip **)res;
1532 gpiochip_remove(chip);
1536 * devm_gpiochip_add_data() - Resource manager gpiochip_add_data()
1537 * @dev: pointer to the device that gpio_chip belongs to.
1538 * @chip: the chip to register, with chip->base initialized
1539 * @data: driver-private data associated with this chip
1541 * Context: potentially before irqs will work
1543 * The gpio chip automatically be released when the device is unbound.
1546 * A negative errno if the chip can't be registered, such as because the
1547 * chip->base is invalid or already associated with a different chip.
1548 * Otherwise it returns zero as a success code.
1550 int devm_gpiochip_add_data(struct device *dev, struct gpio_chip *chip,
1553 struct gpio_chip **ptr;
1556 ptr = devres_alloc(devm_gpio_chip_release, sizeof(*ptr),
1561 ret = gpiochip_add_data(chip, data);
1568 devres_add(dev, ptr);
1572 EXPORT_SYMBOL_GPL(devm_gpiochip_add_data);
1575 * gpiochip_find() - iterator for locating a specific gpio_chip
1576 * @data: data to pass to match function
1577 * @match: Callback function to check gpio_chip
1579 * Similar to bus_find_device. It returns a reference to a gpio_chip as
1580 * determined by a user supplied @match callback. The callback should return
1581 * 0 if the device doesn't match and non-zero if it does. If the callback is
1582 * non-zero, this function will return to the caller and not iterate over any
1585 struct gpio_chip *gpiochip_find(void *data,
1586 int (*match)(struct gpio_chip *chip,
1589 struct gpio_device *gdev;
1590 struct gpio_chip *chip = NULL;
1591 unsigned long flags;
1593 spin_lock_irqsave(&gpio_lock, flags);
1594 list_for_each_entry(gdev, &gpio_devices, list)
1595 if (gdev->chip && match(gdev->chip, data)) {
1600 spin_unlock_irqrestore(&gpio_lock, flags);
1604 EXPORT_SYMBOL_GPL(gpiochip_find);
1606 static int gpiochip_match_name(struct gpio_chip *chip, void *data)
1608 const char *name = data;
1610 return !strcmp(chip->label, name);
1613 static struct gpio_chip *find_chip_by_name(const char *name)
1615 return gpiochip_find((void *)name, gpiochip_match_name);
1618 #ifdef CONFIG_GPIOLIB_IRQCHIP
1621 * The following is irqchip helper code for gpiochips.
1624 static int gpiochip_irqchip_init_valid_mask(struct gpio_chip *gc)
1626 struct gpio_irq_chip *girq = &gc->irq;
1628 if (!girq->init_valid_mask)
1631 girq->valid_mask = gpiochip_allocate_mask(gc);
1632 if (!girq->valid_mask)
1635 girq->init_valid_mask(gc, girq->valid_mask, gc->ngpio);
1640 static void gpiochip_irqchip_free_valid_mask(struct gpio_chip *gpiochip)
1642 bitmap_free(gpiochip->irq.valid_mask);
1643 gpiochip->irq.valid_mask = NULL;
1646 bool gpiochip_irqchip_irq_valid(const struct gpio_chip *gpiochip,
1647 unsigned int offset)
1649 if (!gpiochip_line_is_valid(gpiochip, offset))
1651 /* No mask means all valid */
1652 if (likely(!gpiochip->irq.valid_mask))
1654 return test_bit(offset, gpiochip->irq.valid_mask);
1656 EXPORT_SYMBOL_GPL(gpiochip_irqchip_irq_valid);
1659 * gpiochip_set_cascaded_irqchip() - connects a cascaded irqchip to a gpiochip
1660 * @gc: the gpiochip to set the irqchip chain to
1661 * @parent_irq: the irq number corresponding to the parent IRQ for this
1663 * @parent_handler: the parent interrupt handler for the accumulated IRQ
1664 * coming out of the gpiochip. If the interrupt is nested rather than
1665 * cascaded, pass NULL in this handler argument
1667 static void gpiochip_set_cascaded_irqchip(struct gpio_chip *gc,
1668 unsigned int parent_irq,
1669 irq_flow_handler_t parent_handler)
1671 struct gpio_irq_chip *girq = &gc->irq;
1672 struct device *dev = &gc->gpiodev->dev;
1674 if (!girq->domain) {
1675 chip_err(gc, "called %s before setting up irqchip\n",
1680 if (parent_handler) {
1681 if (gc->can_sleep) {
1683 "you cannot have chained interrupts on a chip that may sleep\n");
1686 girq->parents = devm_kcalloc(dev, 1,
1687 sizeof(*girq->parents),
1689 if (!girq->parents) {
1690 chip_err(gc, "out of memory allocating parent IRQ\n");
1693 girq->parents[0] = parent_irq;
1694 girq->num_parents = 1;
1696 * The parent irqchip is already using the chip_data for this
1697 * irqchip, so our callbacks simply use the handler_data.
1699 irq_set_chained_handler_and_data(parent_irq, parent_handler,
1705 * gpiochip_set_chained_irqchip() - connects a chained irqchip to a gpiochip
1706 * @gpiochip: the gpiochip to set the irqchip chain to
1707 * @irqchip: the irqchip to chain to the gpiochip
1708 * @parent_irq: the irq number corresponding to the parent IRQ for this
1710 * @parent_handler: the parent interrupt handler for the accumulated IRQ
1711 * coming out of the gpiochip.
1713 void gpiochip_set_chained_irqchip(struct gpio_chip *gpiochip,
1714 struct irq_chip *irqchip,
1715 unsigned int parent_irq,
1716 irq_flow_handler_t parent_handler)
1718 if (gpiochip->irq.threaded) {
1719 chip_err(gpiochip, "tried to chain a threaded gpiochip\n");
1723 gpiochip_set_cascaded_irqchip(gpiochip, parent_irq, parent_handler);
1725 EXPORT_SYMBOL_GPL(gpiochip_set_chained_irqchip);
1728 * gpiochip_set_nested_irqchip() - connects a nested irqchip to a gpiochip
1729 * @gpiochip: the gpiochip to set the irqchip nested handler to
1730 * @irqchip: the irqchip to nest to the gpiochip
1731 * @parent_irq: the irq number corresponding to the parent IRQ for this
1734 void gpiochip_set_nested_irqchip(struct gpio_chip *gpiochip,
1735 struct irq_chip *irqchip,
1736 unsigned int parent_irq)
1738 gpiochip_set_cascaded_irqchip(gpiochip, parent_irq, NULL);
1740 EXPORT_SYMBOL_GPL(gpiochip_set_nested_irqchip);
1742 #ifdef CONFIG_IRQ_DOMAIN_HIERARCHY
1745 * gpiochip_set_hierarchical_irqchip() - connects a hierarchical irqchip
1747 * @gc: the gpiochip to set the irqchip hierarchical handler to
1748 * @irqchip: the irqchip to handle this level of the hierarchy, the interrupt
1749 * will then percolate up to the parent
1751 static void gpiochip_set_hierarchical_irqchip(struct gpio_chip *gc,
1752 struct irq_chip *irqchip)
1754 /* DT will deal with mapping each IRQ as we go along */
1755 if (is_of_node(gc->irq.fwnode))
1759 * This is for legacy and boardfile "irqchip" fwnodes: allocate
1760 * irqs upfront instead of dynamically since we don't have the
1761 * dynamic type of allocation that hardware description languages
1762 * provide. Once all GPIO drivers using board files are gone from
1763 * the kernel we can delete this code, but for a transitional period
1764 * it is necessary to keep this around.
1766 if (is_fwnode_irqchip(gc->irq.fwnode)) {
1770 for (i = 0; i < gc->ngpio; i++) {
1771 struct irq_fwspec fwspec;
1772 unsigned int parent_hwirq;
1773 unsigned int parent_type;
1774 struct gpio_irq_chip *girq = &gc->irq;
1777 * We call the child to parent translation function
1778 * only to check if the child IRQ is valid or not.
1779 * Just pick the rising edge type here as that is what
1780 * we likely need to support.
1782 ret = girq->child_to_parent_hwirq(gc, i,
1783 IRQ_TYPE_EDGE_RISING,
1787 chip_err(gc, "skip set-up on hwirq %d\n",
1792 fwspec.fwnode = gc->irq.fwnode;
1793 /* This is the hwirq for the GPIO line side of things */
1794 fwspec.param[0] = girq->child_offset_to_irq(gc, i);
1795 /* Just pick something */
1796 fwspec.param[1] = IRQ_TYPE_EDGE_RISING;
1797 fwspec.param_count = 2;
1798 ret = __irq_domain_alloc_irqs(gc->irq.domain,
1799 /* just pick something */
1808 "can not allocate irq for GPIO line %d parent hwirq %d in hierarchy domain: %d\n",
1815 chip_err(gc, "%s unknown fwnode type proceed anyway\n", __func__);
1820 static int gpiochip_hierarchy_irq_domain_translate(struct irq_domain *d,
1821 struct irq_fwspec *fwspec,
1822 unsigned long *hwirq,
1825 /* We support standard DT translation */
1826 if (is_of_node(fwspec->fwnode) && fwspec->param_count == 2) {
1827 return irq_domain_translate_twocell(d, fwspec, hwirq, type);
1830 /* This is for board files and others not using DT */
1831 if (is_fwnode_irqchip(fwspec->fwnode)) {
1834 ret = irq_domain_translate_twocell(d, fwspec, hwirq, type);
1837 WARN_ON(*type == IRQ_TYPE_NONE);
1843 static int gpiochip_hierarchy_irq_domain_alloc(struct irq_domain *d,
1845 unsigned int nr_irqs,
1848 struct gpio_chip *gc = d->host_data;
1849 irq_hw_number_t hwirq;
1850 unsigned int type = IRQ_TYPE_NONE;
1851 struct irq_fwspec *fwspec = data;
1852 struct irq_fwspec parent_fwspec;
1853 unsigned int parent_hwirq;
1854 unsigned int parent_type;
1855 struct gpio_irq_chip *girq = &gc->irq;
1859 * The nr_irqs parameter is always one except for PCI multi-MSI
1860 * so this should not happen.
1862 WARN_ON(nr_irqs != 1);
1864 ret = gc->irq.child_irq_domain_ops.translate(d, fwspec, &hwirq, &type);
1868 chip_info(gc, "allocate IRQ %d, hwirq %lu\n", irq, hwirq);
1870 ret = girq->child_to_parent_hwirq(gc, hwirq, type,
1871 &parent_hwirq, &parent_type);
1873 chip_err(gc, "can't look up hwirq %lu\n", hwirq);
1876 chip_info(gc, "found parent hwirq %u\n", parent_hwirq);
1879 * We set handle_bad_irq because the .set_type() should
1880 * always be invoked and set the right type of handler.
1882 irq_domain_set_info(d,
1892 * Create a IRQ fwspec to send up to the parent irqdomain:
1893 * specify the hwirq we address on the parent and tie it
1894 * all together up the chain.
1896 parent_fwspec.fwnode = d->parent->fwnode;
1897 /* This parent only handles asserted level IRQs */
1898 girq->populate_parent_fwspec(gc, &parent_fwspec, parent_hwirq,
1900 chip_info(gc, "alloc_irqs_parent for %d parent hwirq %d\n",
1902 ret = irq_domain_alloc_irqs_parent(d, irq, 1, &parent_fwspec);
1905 "failed to allocate parent hwirq %d for hwirq %lu\n",
1906 parent_hwirq, hwirq);
1911 static unsigned int gpiochip_child_offset_to_irq_noop(struct gpio_chip *chip,
1912 unsigned int offset)
1917 static void gpiochip_hierarchy_setup_domain_ops(struct irq_domain_ops *ops)
1919 ops->activate = gpiochip_irq_domain_activate;
1920 ops->deactivate = gpiochip_irq_domain_deactivate;
1921 ops->alloc = gpiochip_hierarchy_irq_domain_alloc;
1922 ops->free = irq_domain_free_irqs_common;
1925 * We only allow overriding the translate() function for
1926 * hierarchical chips, and this should only be done if the user
1927 * really need something other than 1:1 translation.
1929 if (!ops->translate)
1930 ops->translate = gpiochip_hierarchy_irq_domain_translate;
1933 static int gpiochip_hierarchy_add_domain(struct gpio_chip *gc)
1935 if (!gc->irq.child_to_parent_hwirq ||
1937 chip_err(gc, "missing irqdomain vital data\n");
1941 if (!gc->irq.child_offset_to_irq)
1942 gc->irq.child_offset_to_irq = gpiochip_child_offset_to_irq_noop;
1944 if (!gc->irq.populate_parent_fwspec)
1945 gc->irq.populate_parent_fwspec =
1946 gpiochip_populate_parent_fwspec_twocell;
1948 gpiochip_hierarchy_setup_domain_ops(&gc->irq.child_irq_domain_ops);
1950 gc->irq.domain = irq_domain_create_hierarchy(
1951 gc->irq.parent_domain,
1955 &gc->irq.child_irq_domain_ops,
1958 if (!gc->irq.domain)
1961 gpiochip_set_hierarchical_irqchip(gc, gc->irq.chip);
1966 static bool gpiochip_hierarchy_is_hierarchical(struct gpio_chip *gc)
1968 return !!gc->irq.parent_domain;
1971 void gpiochip_populate_parent_fwspec_twocell(struct gpio_chip *chip,
1972 struct irq_fwspec *fwspec,
1973 unsigned int parent_hwirq,
1974 unsigned int parent_type)
1976 fwspec->param_count = 2;
1977 fwspec->param[0] = parent_hwirq;
1978 fwspec->param[1] = parent_type;
1980 EXPORT_SYMBOL_GPL(gpiochip_populate_parent_fwspec_twocell);
1982 void gpiochip_populate_parent_fwspec_fourcell(struct gpio_chip *chip,
1983 struct irq_fwspec *fwspec,
1984 unsigned int parent_hwirq,
1985 unsigned int parent_type)
1987 fwspec->param_count = 4;
1988 fwspec->param[0] = 0;
1989 fwspec->param[1] = parent_hwirq;
1990 fwspec->param[2] = 0;
1991 fwspec->param[3] = parent_type;
1993 EXPORT_SYMBOL_GPL(gpiochip_populate_parent_fwspec_fourcell);
1997 static int gpiochip_hierarchy_add_domain(struct gpio_chip *gc)
2002 static bool gpiochip_hierarchy_is_hierarchical(struct gpio_chip *gc)
2007 #endif /* CONFIG_IRQ_DOMAIN_HIERARCHY */
2010 * gpiochip_irq_map() - maps an IRQ into a GPIO irqchip
2011 * @d: the irqdomain used by this irqchip
2012 * @irq: the global irq number used by this GPIO irqchip irq
2013 * @hwirq: the local IRQ/GPIO line offset on this gpiochip
2015 * This function will set up the mapping for a certain IRQ line on a
2016 * gpiochip by assigning the gpiochip as chip data, and using the irqchip
2017 * stored inside the gpiochip.
2019 int gpiochip_irq_map(struct irq_domain *d, unsigned int irq,
2020 irq_hw_number_t hwirq)
2022 struct gpio_chip *chip = d->host_data;
2025 if (!gpiochip_irqchip_irq_valid(chip, hwirq))
2028 irq_set_chip_data(irq, chip);
2030 * This lock class tells lockdep that GPIO irqs are in a different
2031 * category than their parents, so it won't report false recursion.
2033 irq_set_lockdep_class(irq, chip->irq.lock_key, chip->irq.request_key);
2034 irq_set_chip_and_handler(irq, chip->irq.chip, chip->irq.handler);
2035 /* Chips that use nested thread handlers have them marked */
2036 if (chip->irq.threaded)
2037 irq_set_nested_thread(irq, 1);
2038 irq_set_noprobe(irq);
2040 if (chip->irq.num_parents == 1)
2041 ret = irq_set_parent(irq, chip->irq.parents[0]);
2042 else if (chip->irq.map)
2043 ret = irq_set_parent(irq, chip->irq.map[hwirq]);
2049 * No set-up of the hardware will happen if IRQ_TYPE_NONE
2050 * is passed as default type.
2052 if (chip->irq.default_type != IRQ_TYPE_NONE)
2053 irq_set_irq_type(irq, chip->irq.default_type);
2057 EXPORT_SYMBOL_GPL(gpiochip_irq_map);
2059 void gpiochip_irq_unmap(struct irq_domain *d, unsigned int irq)
2061 struct gpio_chip *chip = d->host_data;
2063 if (chip->irq.threaded)
2064 irq_set_nested_thread(irq, 0);
2065 irq_set_chip_and_handler(irq, NULL, NULL);
2066 irq_set_chip_data(irq, NULL);
2068 EXPORT_SYMBOL_GPL(gpiochip_irq_unmap);
2070 static const struct irq_domain_ops gpiochip_domain_ops = {
2071 .map = gpiochip_irq_map,
2072 .unmap = gpiochip_irq_unmap,
2073 /* Virtually all GPIO irqchips are twocell:ed */
2074 .xlate = irq_domain_xlate_twocell,
2078 * TODO: move these activate/deactivate in under the hierarchicial
2079 * irqchip implementation as static once SPMI and SSBI (all external
2080 * users) are phased over.
2083 * gpiochip_irq_domain_activate() - Lock a GPIO to be used as an IRQ
2084 * @domain: The IRQ domain used by this IRQ chip
2085 * @data: Outermost irq_data associated with the IRQ
2086 * @reserve: If set, only reserve an interrupt vector instead of assigning one
2088 * This function is a wrapper that calls gpiochip_lock_as_irq() and is to be
2089 * used as the activate function for the &struct irq_domain_ops. The host_data
2090 * for the IRQ domain must be the &struct gpio_chip.
2092 int gpiochip_irq_domain_activate(struct irq_domain *domain,
2093 struct irq_data *data, bool reserve)
2095 struct gpio_chip *chip = domain->host_data;
2097 return gpiochip_lock_as_irq(chip, data->hwirq);
2099 EXPORT_SYMBOL_GPL(gpiochip_irq_domain_activate);
2102 * gpiochip_irq_domain_deactivate() - Unlock a GPIO used as an IRQ
2103 * @domain: The IRQ domain used by this IRQ chip
2104 * @data: Outermost irq_data associated with the IRQ
2106 * This function is a wrapper that will call gpiochip_unlock_as_irq() and is to
2107 * be used as the deactivate function for the &struct irq_domain_ops. The
2108 * host_data for the IRQ domain must be the &struct gpio_chip.
2110 void gpiochip_irq_domain_deactivate(struct irq_domain *domain,
2111 struct irq_data *data)
2113 struct gpio_chip *chip = domain->host_data;
2115 return gpiochip_unlock_as_irq(chip, data->hwirq);
2117 EXPORT_SYMBOL_GPL(gpiochip_irq_domain_deactivate);
2119 static int gpiochip_to_irq(struct gpio_chip *chip, unsigned offset)
2121 struct irq_domain *domain = chip->irq.domain;
2123 if (!gpiochip_irqchip_irq_valid(chip, offset))
2126 #ifdef CONFIG_IRQ_DOMAIN_HIERARCHY
2127 if (irq_domain_is_hierarchy(domain)) {
2128 struct irq_fwspec spec;
2130 spec.fwnode = domain->fwnode;
2131 spec.param_count = 2;
2132 spec.param[0] = chip->irq.child_offset_to_irq(chip, offset);
2133 spec.param[1] = IRQ_TYPE_NONE;
2135 return irq_create_fwspec_mapping(&spec);
2139 return irq_create_mapping(domain, offset);
2142 static int gpiochip_irq_reqres(struct irq_data *d)
2144 struct gpio_chip *chip = irq_data_get_irq_chip_data(d);
2146 return gpiochip_reqres_irq(chip, d->hwirq);
2149 static void gpiochip_irq_relres(struct irq_data *d)
2151 struct gpio_chip *chip = irq_data_get_irq_chip_data(d);
2153 gpiochip_relres_irq(chip, d->hwirq);
2156 static void gpiochip_irq_enable(struct irq_data *d)
2158 struct gpio_chip *chip = irq_data_get_irq_chip_data(d);
2160 gpiochip_enable_irq(chip, d->hwirq);
2161 if (chip->irq.irq_enable)
2162 chip->irq.irq_enable(d);
2164 chip->irq.chip->irq_unmask(d);
2167 static void gpiochip_irq_disable(struct irq_data *d)
2169 struct gpio_chip *chip = irq_data_get_irq_chip_data(d);
2171 if (chip->irq.irq_disable)
2172 chip->irq.irq_disable(d);
2174 chip->irq.chip->irq_mask(d);
2175 gpiochip_disable_irq(chip, d->hwirq);
2178 static void gpiochip_set_irq_hooks(struct gpio_chip *gpiochip)
2180 struct irq_chip *irqchip = gpiochip->irq.chip;
2182 if (!irqchip->irq_request_resources &&
2183 !irqchip->irq_release_resources) {
2184 irqchip->irq_request_resources = gpiochip_irq_reqres;
2185 irqchip->irq_release_resources = gpiochip_irq_relres;
2187 if (WARN_ON(gpiochip->irq.irq_enable))
2189 /* Check if the irqchip already has this hook... */
2190 if (irqchip->irq_enable == gpiochip_irq_enable) {
2192 * ...and if so, give a gentle warning that this is bad
2196 "detected irqchip that is shared with multiple gpiochips: please fix the driver.\n");
2199 gpiochip->irq.irq_enable = irqchip->irq_enable;
2200 gpiochip->irq.irq_disable = irqchip->irq_disable;
2201 irqchip->irq_enable = gpiochip_irq_enable;
2202 irqchip->irq_disable = gpiochip_irq_disable;
2206 * gpiochip_add_irqchip() - adds an IRQ chip to a GPIO chip
2207 * @gpiochip: the GPIO chip to add the IRQ chip to
2208 * @lock_key: lockdep class for IRQ lock
2209 * @request_key: lockdep class for IRQ request
2211 static int gpiochip_add_irqchip(struct gpio_chip *gpiochip,
2212 struct lock_class_key *lock_key,
2213 struct lock_class_key *request_key)
2215 struct irq_chip *irqchip = gpiochip->irq.chip;
2216 const struct irq_domain_ops *ops = NULL;
2217 struct device_node *np;
2224 if (gpiochip->irq.parent_handler && gpiochip->can_sleep) {
2225 chip_err(gpiochip, "you cannot have chained interrupts on a chip that may sleep\n");
2229 np = gpiochip->gpiodev->dev.of_node;
2230 type = gpiochip->irq.default_type;
2233 * Specifying a default trigger is a terrible idea if DT or ACPI is
2234 * used to configure the interrupts, as you may end up with
2235 * conflicting triggers. Tell the user, and reset to NONE.
2237 if (WARN(np && type != IRQ_TYPE_NONE,
2238 "%s: Ignoring %u default trigger\n", np->full_name, type))
2239 type = IRQ_TYPE_NONE;
2241 if (has_acpi_companion(gpiochip->parent) && type != IRQ_TYPE_NONE) {
2242 acpi_handle_warn(ACPI_HANDLE(gpiochip->parent),
2243 "Ignoring %u default trigger\n", type);
2244 type = IRQ_TYPE_NONE;
2247 gpiochip->to_irq = gpiochip_to_irq;
2248 gpiochip->irq.default_type = type;
2249 gpiochip->irq.lock_key = lock_key;
2250 gpiochip->irq.request_key = request_key;
2252 /* If a parent irqdomain is provided, let's build a hierarchy */
2253 if (gpiochip_hierarchy_is_hierarchical(gpiochip)) {
2254 int ret = gpiochip_hierarchy_add_domain(gpiochip);
2258 /* Some drivers provide custom irqdomain ops */
2259 if (gpiochip->irq.domain_ops)
2260 ops = gpiochip->irq.domain_ops;
2263 ops = &gpiochip_domain_ops;
2264 gpiochip->irq.domain = irq_domain_add_simple(np,
2266 gpiochip->irq.first,
2268 if (!gpiochip->irq.domain)
2272 if (gpiochip->irq.parent_handler) {
2273 void *data = gpiochip->irq.parent_handler_data ?: gpiochip;
2275 for (i = 0; i < gpiochip->irq.num_parents; i++) {
2277 * The parent IRQ chip is already using the chip_data
2278 * for this IRQ chip, so our callbacks simply use the
2281 irq_set_chained_handler_and_data(gpiochip->irq.parents[i],
2282 gpiochip->irq.parent_handler,
2287 gpiochip_set_irq_hooks(gpiochip);
2289 acpi_gpiochip_request_interrupts(gpiochip);
2295 * gpiochip_irqchip_remove() - removes an irqchip added to a gpiochip
2296 * @gpiochip: the gpiochip to remove the irqchip from
2298 * This is called only from gpiochip_remove()
2300 static void gpiochip_irqchip_remove(struct gpio_chip *gpiochip)
2302 struct irq_chip *irqchip = gpiochip->irq.chip;
2303 unsigned int offset;
2305 acpi_gpiochip_free_interrupts(gpiochip);
2307 if (irqchip && gpiochip->irq.parent_handler) {
2308 struct gpio_irq_chip *irq = &gpiochip->irq;
2311 for (i = 0; i < irq->num_parents; i++)
2312 irq_set_chained_handler_and_data(irq->parents[i],
2316 /* Remove all IRQ mappings and delete the domain */
2317 if (gpiochip->irq.domain) {
2320 for (offset = 0; offset < gpiochip->ngpio; offset++) {
2321 if (!gpiochip_irqchip_irq_valid(gpiochip, offset))
2324 irq = irq_find_mapping(gpiochip->irq.domain, offset);
2325 irq_dispose_mapping(irq);
2328 irq_domain_remove(gpiochip->irq.domain);
2332 if (irqchip->irq_request_resources == gpiochip_irq_reqres) {
2333 irqchip->irq_request_resources = NULL;
2334 irqchip->irq_release_resources = NULL;
2336 if (irqchip->irq_enable == gpiochip_irq_enable) {
2337 irqchip->irq_enable = gpiochip->irq.irq_enable;
2338 irqchip->irq_disable = gpiochip->irq.irq_disable;
2341 gpiochip->irq.irq_enable = NULL;
2342 gpiochip->irq.irq_disable = NULL;
2343 gpiochip->irq.chip = NULL;
2345 gpiochip_irqchip_free_valid_mask(gpiochip);
2349 * gpiochip_irqchip_add_key() - adds an irqchip to a gpiochip
2350 * @gpiochip: the gpiochip to add the irqchip to
2351 * @irqchip: the irqchip to add to the gpiochip
2352 * @first_irq: if not dynamically assigned, the base (first) IRQ to
2353 * allocate gpiochip irqs from
2354 * @handler: the irq handler to use (often a predefined irq core function)
2355 * @type: the default type for IRQs on this irqchip, pass IRQ_TYPE_NONE
2356 * to have the core avoid setting up any default type in the hardware.
2357 * @threaded: whether this irqchip uses a nested thread handler
2358 * @lock_key: lockdep class for IRQ lock
2359 * @request_key: lockdep class for IRQ request
2361 * This function closely associates a certain irqchip with a certain
2362 * gpiochip, providing an irq domain to translate the local IRQs to
2363 * global irqs in the gpiolib core, and making sure that the gpiochip
2364 * is passed as chip data to all related functions. Driver callbacks
2365 * need to use gpiochip_get_data() to get their local state containers back
2366 * from the gpiochip passed as chip data. An irqdomain will be stored
2367 * in the gpiochip that shall be used by the driver to handle IRQ number
2368 * translation. The gpiochip will need to be initialized and registered
2369 * before calling this function.
2371 * This function will handle two cell:ed simple IRQs and assumes all
2372 * the pins on the gpiochip can generate a unique IRQ. Everything else
2373 * need to be open coded.
2375 int gpiochip_irqchip_add_key(struct gpio_chip *gpiochip,
2376 struct irq_chip *irqchip,
2377 unsigned int first_irq,
2378 irq_flow_handler_t handler,
2381 struct lock_class_key *lock_key,
2382 struct lock_class_key *request_key)
2384 struct device_node *of_node;
2386 if (!gpiochip || !irqchip)
2389 if (!gpiochip->parent) {
2390 pr_err("missing gpiochip .dev parent pointer\n");
2393 gpiochip->irq.threaded = threaded;
2394 of_node = gpiochip->parent->of_node;
2395 #ifdef CONFIG_OF_GPIO
2397 * If the gpiochip has an assigned OF node this takes precedence
2398 * FIXME: get rid of this and use gpiochip->parent->of_node
2401 if (gpiochip->of_node)
2402 of_node = gpiochip->of_node;
2405 * Specifying a default trigger is a terrible idea if DT or ACPI is
2406 * used to configure the interrupts, as you may end-up with
2407 * conflicting triggers. Tell the user, and reset to NONE.
2409 if (WARN(of_node && type != IRQ_TYPE_NONE,
2410 "%pOF: Ignoring %d default trigger\n", of_node, type))
2411 type = IRQ_TYPE_NONE;
2412 if (has_acpi_companion(gpiochip->parent) && type != IRQ_TYPE_NONE) {
2413 acpi_handle_warn(ACPI_HANDLE(gpiochip->parent),
2414 "Ignoring %d default trigger\n", type);
2415 type = IRQ_TYPE_NONE;
2418 gpiochip->irq.chip = irqchip;
2419 gpiochip->irq.handler = handler;
2420 gpiochip->irq.default_type = type;
2421 gpiochip->to_irq = gpiochip_to_irq;
2422 gpiochip->irq.lock_key = lock_key;
2423 gpiochip->irq.request_key = request_key;
2424 gpiochip->irq.domain = irq_domain_add_simple(of_node,
2425 gpiochip->ngpio, first_irq,
2426 &gpiochip_domain_ops, gpiochip);
2427 if (!gpiochip->irq.domain) {
2428 gpiochip->irq.chip = NULL;
2432 gpiochip_set_irq_hooks(gpiochip);
2434 acpi_gpiochip_request_interrupts(gpiochip);
2438 EXPORT_SYMBOL_GPL(gpiochip_irqchip_add_key);
2440 #else /* CONFIG_GPIOLIB_IRQCHIP */
2442 static inline int gpiochip_add_irqchip(struct gpio_chip *gpiochip,
2443 struct lock_class_key *lock_key,
2444 struct lock_class_key *request_key)
2449 static void gpiochip_irqchip_remove(struct gpio_chip *gpiochip) {}
2450 static inline int gpiochip_irqchip_init_valid_mask(struct gpio_chip *gpiochip)
2454 static inline void gpiochip_irqchip_free_valid_mask(struct gpio_chip *gpiochip)
2457 #endif /* CONFIG_GPIOLIB_IRQCHIP */
2460 * gpiochip_generic_request() - request the gpio function for a pin
2461 * @chip: the gpiochip owning the GPIO
2462 * @offset: the offset of the GPIO to request for GPIO function
2464 int gpiochip_generic_request(struct gpio_chip *chip, unsigned offset)
2466 return pinctrl_gpio_request(chip->gpiodev->base + offset);
2468 EXPORT_SYMBOL_GPL(gpiochip_generic_request);
2471 * gpiochip_generic_free() - free the gpio function from a pin
2472 * @chip: the gpiochip to request the gpio function for
2473 * @offset: the offset of the GPIO to free from GPIO function
2475 void gpiochip_generic_free(struct gpio_chip *chip, unsigned offset)
2477 pinctrl_gpio_free(chip->gpiodev->base + offset);
2479 EXPORT_SYMBOL_GPL(gpiochip_generic_free);
2482 * gpiochip_generic_config() - apply configuration for a pin
2483 * @chip: the gpiochip owning the GPIO
2484 * @offset: the offset of the GPIO to apply the configuration
2485 * @config: the configuration to be applied
2487 int gpiochip_generic_config(struct gpio_chip *chip, unsigned offset,
2488 unsigned long config)
2490 return pinctrl_gpio_set_config(chip->gpiodev->base + offset, config);
2492 EXPORT_SYMBOL_GPL(gpiochip_generic_config);
2494 #ifdef CONFIG_PINCTRL
2497 * gpiochip_add_pingroup_range() - add a range for GPIO <-> pin mapping
2498 * @chip: the gpiochip to add the range for
2499 * @pctldev: the pin controller to map to
2500 * @gpio_offset: the start offset in the current gpio_chip number space
2501 * @pin_group: name of the pin group inside the pin controller
2503 * Calling this function directly from a DeviceTree-supported
2504 * pinctrl driver is DEPRECATED. Please see Section 2.1 of
2505 * Documentation/devicetree/bindings/gpio/gpio.txt on how to
2506 * bind pinctrl and gpio drivers via the "gpio-ranges" property.
2508 int gpiochip_add_pingroup_range(struct gpio_chip *chip,
2509 struct pinctrl_dev *pctldev,
2510 unsigned int gpio_offset, const char *pin_group)
2512 struct gpio_pin_range *pin_range;
2513 struct gpio_device *gdev = chip->gpiodev;
2516 pin_range = kzalloc(sizeof(*pin_range), GFP_KERNEL);
2518 chip_err(chip, "failed to allocate pin ranges\n");
2522 /* Use local offset as range ID */
2523 pin_range->range.id = gpio_offset;
2524 pin_range->range.gc = chip;
2525 pin_range->range.name = chip->label;
2526 pin_range->range.base = gdev->base + gpio_offset;
2527 pin_range->pctldev = pctldev;
2529 ret = pinctrl_get_group_pins(pctldev, pin_group,
2530 &pin_range->range.pins,
2531 &pin_range->range.npins);
2537 pinctrl_add_gpio_range(pctldev, &pin_range->range);
2539 chip_dbg(chip, "created GPIO range %d->%d ==> %s PINGRP %s\n",
2540 gpio_offset, gpio_offset + pin_range->range.npins - 1,
2541 pinctrl_dev_get_devname(pctldev), pin_group);
2543 list_add_tail(&pin_range->node, &gdev->pin_ranges);
2547 EXPORT_SYMBOL_GPL(gpiochip_add_pingroup_range);
2550 * gpiochip_add_pin_range() - add a range for GPIO <-> pin mapping
2551 * @chip: the gpiochip to add the range for
2552 * @pinctl_name: the dev_name() of the pin controller to map to
2553 * @gpio_offset: the start offset in the current gpio_chip number space
2554 * @pin_offset: the start offset in the pin controller number space
2555 * @npins: the number of pins from the offset of each pin space (GPIO and
2556 * pin controller) to accumulate in this range
2559 * 0 on success, or a negative error-code on failure.
2561 * Calling this function directly from a DeviceTree-supported
2562 * pinctrl driver is DEPRECATED. Please see Section 2.1 of
2563 * Documentation/devicetree/bindings/gpio/gpio.txt on how to
2564 * bind pinctrl and gpio drivers via the "gpio-ranges" property.
2566 int gpiochip_add_pin_range(struct gpio_chip *chip, const char *pinctl_name,
2567 unsigned int gpio_offset, unsigned int pin_offset,
2570 struct gpio_pin_range *pin_range;
2571 struct gpio_device *gdev = chip->gpiodev;
2574 pin_range = kzalloc(sizeof(*pin_range), GFP_KERNEL);
2576 chip_err(chip, "failed to allocate pin ranges\n");
2580 /* Use local offset as range ID */
2581 pin_range->range.id = gpio_offset;
2582 pin_range->range.gc = chip;
2583 pin_range->range.name = chip->label;
2584 pin_range->range.base = gdev->base + gpio_offset;
2585 pin_range->range.pin_base = pin_offset;
2586 pin_range->range.npins = npins;
2587 pin_range->pctldev = pinctrl_find_and_add_gpio_range(pinctl_name,
2589 if (IS_ERR(pin_range->pctldev)) {
2590 ret = PTR_ERR(pin_range->pctldev);
2591 chip_err(chip, "could not create pin range\n");
2595 chip_dbg(chip, "created GPIO range %d->%d ==> %s PIN %d->%d\n",
2596 gpio_offset, gpio_offset + npins - 1,
2598 pin_offset, pin_offset + npins - 1);
2600 list_add_tail(&pin_range->node, &gdev->pin_ranges);
2604 EXPORT_SYMBOL_GPL(gpiochip_add_pin_range);
2607 * gpiochip_remove_pin_ranges() - remove all the GPIO <-> pin mappings
2608 * @chip: the chip to remove all the mappings for
2610 void gpiochip_remove_pin_ranges(struct gpio_chip *chip)
2612 struct gpio_pin_range *pin_range, *tmp;
2613 struct gpio_device *gdev = chip->gpiodev;
2615 list_for_each_entry_safe(pin_range, tmp, &gdev->pin_ranges, node) {
2616 list_del(&pin_range->node);
2617 pinctrl_remove_gpio_range(pin_range->pctldev,
2622 EXPORT_SYMBOL_GPL(gpiochip_remove_pin_ranges);
2624 #endif /* CONFIG_PINCTRL */
2626 /* These "optional" allocation calls help prevent drivers from stomping
2627 * on each other, and help provide better diagnostics in debugfs.
2628 * They're called even less than the "set direction" calls.
2630 static int gpiod_request_commit(struct gpio_desc *desc, const char *label)
2632 struct gpio_chip *chip = desc->gdev->chip;
2634 unsigned long flags;
2638 label = kstrdup_const(label, GFP_KERNEL);
2643 spin_lock_irqsave(&gpio_lock, flags);
2645 /* NOTE: gpio_request() can be called in early boot,
2646 * before IRQs are enabled, for non-sleeping (SOC) GPIOs.
2649 if (test_and_set_bit(FLAG_REQUESTED, &desc->flags) == 0) {
2650 desc_set_label(desc, label ? : "?");
2658 if (chip->request) {
2659 /* chip->request may sleep */
2660 spin_unlock_irqrestore(&gpio_lock, flags);
2661 offset = gpio_chip_hwgpio(desc);
2662 if (gpiochip_line_is_valid(chip, offset))
2663 ret = chip->request(chip, offset);
2666 spin_lock_irqsave(&gpio_lock, flags);
2669 desc_set_label(desc, NULL);
2671 clear_bit(FLAG_REQUESTED, &desc->flags);
2675 if (chip->get_direction) {
2676 /* chip->get_direction may sleep */
2677 spin_unlock_irqrestore(&gpio_lock, flags);
2678 gpiod_get_direction(desc);
2679 spin_lock_irqsave(&gpio_lock, flags);
2682 spin_unlock_irqrestore(&gpio_lock, flags);
2687 * This descriptor validation needs to be inserted verbatim into each
2688 * function taking a descriptor, so we need to use a preprocessor
2689 * macro to avoid endless duplication. If the desc is NULL it is an
2690 * optional GPIO and calls should just bail out.
2692 static int validate_desc(const struct gpio_desc *desc, const char *func)
2697 pr_warn("%s: invalid GPIO (errorpointer)\n", func);
2698 return PTR_ERR(desc);
2701 pr_warn("%s: invalid GPIO (no device)\n", func);
2704 if (!desc->gdev->chip) {
2705 dev_warn(&desc->gdev->dev,
2706 "%s: backing chip is gone\n", func);
2712 #define VALIDATE_DESC(desc) do { \
2713 int __valid = validate_desc(desc, __func__); \
2718 #define VALIDATE_DESC_VOID(desc) do { \
2719 int __valid = validate_desc(desc, __func__); \
2724 int gpiod_request(struct gpio_desc *desc, const char *label)
2726 int ret = -EPROBE_DEFER;
2727 struct gpio_device *gdev;
2729 VALIDATE_DESC(desc);
2732 if (try_module_get(gdev->owner)) {
2733 ret = gpiod_request_commit(desc, label);
2735 module_put(gdev->owner);
2737 get_device(&gdev->dev);
2741 gpiod_dbg(desc, "%s: status %d\n", __func__, ret);
2746 static bool gpiod_free_commit(struct gpio_desc *desc)
2749 unsigned long flags;
2750 struct gpio_chip *chip;
2754 gpiod_unexport(desc);
2756 spin_lock_irqsave(&gpio_lock, flags);
2758 chip = desc->gdev->chip;
2759 if (chip && test_bit(FLAG_REQUESTED, &desc->flags)) {
2761 spin_unlock_irqrestore(&gpio_lock, flags);
2762 might_sleep_if(chip->can_sleep);
2763 chip->free(chip, gpio_chip_hwgpio(desc));
2764 spin_lock_irqsave(&gpio_lock, flags);
2766 kfree_const(desc->label);
2767 desc_set_label(desc, NULL);
2768 clear_bit(FLAG_ACTIVE_LOW, &desc->flags);
2769 clear_bit(FLAG_REQUESTED, &desc->flags);
2770 clear_bit(FLAG_OPEN_DRAIN, &desc->flags);
2771 clear_bit(FLAG_OPEN_SOURCE, &desc->flags);
2772 clear_bit(FLAG_IS_HOGGED, &desc->flags);
2776 spin_unlock_irqrestore(&gpio_lock, flags);
2780 void gpiod_free(struct gpio_desc *desc)
2782 if (desc && desc->gdev && gpiod_free_commit(desc)) {
2783 module_put(desc->gdev->owner);
2784 put_device(&desc->gdev->dev);
2786 WARN_ON(extra_checks);
2791 * gpiochip_is_requested - return string iff signal was requested
2792 * @chip: controller managing the signal
2793 * @offset: of signal within controller's 0..(ngpio - 1) range
2795 * Returns NULL if the GPIO is not currently requested, else a string.
2796 * The string returned is the label passed to gpio_request(); if none has been
2797 * passed it is a meaningless, non-NULL constant.
2799 * This function is for use by GPIO controller drivers. The label can
2800 * help with diagnostics, and knowing that the signal is used as a GPIO
2801 * can help avoid accidentally multiplexing it to another controller.
2803 const char *gpiochip_is_requested(struct gpio_chip *chip, unsigned offset)
2805 struct gpio_desc *desc;
2807 if (offset >= chip->ngpio)
2810 desc = &chip->gpiodev->descs[offset];
2812 if (test_bit(FLAG_REQUESTED, &desc->flags) == 0)
2816 EXPORT_SYMBOL_GPL(gpiochip_is_requested);
2819 * gpiochip_request_own_desc - Allow GPIO chip to request its own descriptor
2821 * @hwnum: hardware number of the GPIO for which to request the descriptor
2822 * @label: label for the GPIO
2823 * @lflags: lookup flags for this GPIO or 0 if default, this can be used to
2824 * specify things like line inversion semantics with the machine flags
2825 * such as GPIO_OUT_LOW
2826 * @dflags: descriptor request flags for this GPIO or 0 if default, this
2827 * can be used to specify consumer semantics such as open drain
2829 * Function allows GPIO chip drivers to request and use their own GPIO
2830 * descriptors via gpiolib API. Difference to gpiod_request() is that this
2831 * function will not increase reference count of the GPIO chip module. This
2832 * allows the GPIO chip module to be unloaded as needed (we assume that the
2833 * GPIO chip driver handles freeing the GPIOs it has requested).
2836 * A pointer to the GPIO descriptor, or an ERR_PTR()-encoded negative error
2839 struct gpio_desc *gpiochip_request_own_desc(struct gpio_chip *chip, u16 hwnum,
2841 enum gpio_lookup_flags lflags,
2842 enum gpiod_flags dflags)
2844 struct gpio_desc *desc = gpiochip_get_desc(chip, hwnum);
2848 chip_err(chip, "failed to get GPIO descriptor\n");
2852 ret = gpiod_request_commit(desc, label);
2854 return ERR_PTR(ret);
2856 ret = gpiod_configure_flags(desc, label, lflags, dflags);
2858 chip_err(chip, "setup of own GPIO %s failed\n", label);
2859 gpiod_free_commit(desc);
2860 return ERR_PTR(ret);
2865 EXPORT_SYMBOL_GPL(gpiochip_request_own_desc);
2868 * gpiochip_free_own_desc - Free GPIO requested by the chip driver
2869 * @desc: GPIO descriptor to free
2871 * Function frees the given GPIO requested previously with
2872 * gpiochip_request_own_desc().
2874 void gpiochip_free_own_desc(struct gpio_desc *desc)
2877 gpiod_free_commit(desc);
2879 EXPORT_SYMBOL_GPL(gpiochip_free_own_desc);
2882 * Drivers MUST set GPIO direction before making get/set calls. In
2883 * some cases this is done in early boot, before IRQs are enabled.
2885 * As a rule these aren't called more than once (except for drivers
2886 * using the open-drain emulation idiom) so these are natural places
2887 * to accumulate extra debugging checks. Note that we can't (yet)
2888 * rely on gpio_request() having been called beforehand.
2891 static int gpio_set_config(struct gpio_chip *gc, unsigned offset,
2892 enum pin_config_param mode)
2894 unsigned long config;
2898 case PIN_CONFIG_BIAS_PULL_DOWN:
2899 case PIN_CONFIG_BIAS_PULL_UP:
2907 config = PIN_CONF_PACKED(mode, arg);
2908 return gc->set_config ? gc->set_config(gc, offset, config) : -ENOTSUPP;
2912 * gpiod_direction_input - set the GPIO direction to input
2913 * @desc: GPIO to set to input
2915 * Set the direction of the passed GPIO to input, such as gpiod_get_value() can
2916 * be called safely on it.
2918 * Return 0 in case of success, else an error code.
2920 int gpiod_direction_input(struct gpio_desc *desc)
2922 struct gpio_chip *chip;
2925 VALIDATE_DESC(desc);
2926 chip = desc->gdev->chip;
2929 * It is legal to have no .get() and .direction_input() specified if
2930 * the chip is output-only, but you can't specify .direction_input()
2931 * and not support the .get() operation, that doesn't make sense.
2933 if (!chip->get && chip->direction_input) {
2935 "%s: missing get() but have direction_input()\n",
2941 * If we have a .direction_input() callback, things are simple,
2942 * just call it. Else we are some input-only chip so try to check the
2943 * direction (if .get_direction() is supported) else we silently
2944 * assume we are in input mode after this.
2946 if (chip->direction_input) {
2947 ret = chip->direction_input(chip, gpio_chip_hwgpio(desc));
2948 } else if (chip->get_direction &&
2949 (chip->get_direction(chip, gpio_chip_hwgpio(desc)) != 1)) {
2951 "%s: missing direction_input() operation and line is output\n",
2956 clear_bit(FLAG_IS_OUT, &desc->flags);
2958 if (test_bit(FLAG_PULL_UP, &desc->flags))
2959 gpio_set_config(chip, gpio_chip_hwgpio(desc),
2960 PIN_CONFIG_BIAS_PULL_UP);
2961 else if (test_bit(FLAG_PULL_DOWN, &desc->flags))
2962 gpio_set_config(chip, gpio_chip_hwgpio(desc),
2963 PIN_CONFIG_BIAS_PULL_DOWN);
2965 trace_gpio_direction(desc_to_gpio(desc), 1, ret);
2969 EXPORT_SYMBOL_GPL(gpiod_direction_input);
2971 static int gpiod_direction_output_raw_commit(struct gpio_desc *desc, int value)
2973 struct gpio_chip *gc = desc->gdev->chip;
2978 * It's OK not to specify .direction_output() if the gpiochip is
2979 * output-only, but if there is then not even a .set() operation it
2980 * is pretty tricky to drive the output line.
2982 if (!gc->set && !gc->direction_output) {
2984 "%s: missing set() and direction_output() operations\n",
2989 if (gc->direction_output) {
2990 ret = gc->direction_output(gc, gpio_chip_hwgpio(desc), val);
2992 /* Check that we are in output mode if we can */
2993 if (gc->get_direction &&
2994 gc->get_direction(gc, gpio_chip_hwgpio(desc))) {
2996 "%s: missing direction_output() operation\n",
3001 * If we can't actively set the direction, we are some
3002 * output-only chip, so just drive the output as desired.
3004 gc->set(gc, gpio_chip_hwgpio(desc), val);
3008 set_bit(FLAG_IS_OUT, &desc->flags);
3009 trace_gpio_value(desc_to_gpio(desc), 0, val);
3010 trace_gpio_direction(desc_to_gpio(desc), 0, ret);
3015 * gpiod_direction_output_raw - set the GPIO direction to output
3016 * @desc: GPIO to set to output
3017 * @value: initial output value of the GPIO
3019 * Set the direction of the passed GPIO to output, such as gpiod_set_value() can
3020 * be called safely on it. The initial value of the output must be specified
3021 * as raw value on the physical line without regard for the ACTIVE_LOW status.
3023 * Return 0 in case of success, else an error code.
3025 int gpiod_direction_output_raw(struct gpio_desc *desc, int value)
3027 VALIDATE_DESC(desc);
3028 return gpiod_direction_output_raw_commit(desc, value);
3030 EXPORT_SYMBOL_GPL(gpiod_direction_output_raw);
3033 * gpiod_direction_output - set the GPIO direction to output
3034 * @desc: GPIO to set to output
3035 * @value: initial output value of the GPIO
3037 * Set the direction of the passed GPIO to output, such as gpiod_set_value() can
3038 * be called safely on it. The initial value of the output must be specified
3039 * as the logical value of the GPIO, i.e. taking its ACTIVE_LOW status into
3042 * Return 0 in case of success, else an error code.
3044 int gpiod_direction_output(struct gpio_desc *desc, int value)
3046 struct gpio_chip *gc;
3049 VALIDATE_DESC(desc);
3050 if (test_bit(FLAG_ACTIVE_LOW, &desc->flags))
3055 /* GPIOs used for enabled IRQs shall not be set as output */
3056 if (test_bit(FLAG_USED_AS_IRQ, &desc->flags) &&
3057 test_bit(FLAG_IRQ_IS_ENABLED, &desc->flags)) {
3059 "%s: tried to set a GPIO tied to an IRQ as output\n",
3064 gc = desc->gdev->chip;
3065 if (test_bit(FLAG_OPEN_DRAIN, &desc->flags)) {
3066 /* First see if we can enable open drain in hardware */
3067 ret = gpio_set_config(gc, gpio_chip_hwgpio(desc),
3068 PIN_CONFIG_DRIVE_OPEN_DRAIN);
3070 goto set_output_value;
3071 /* Emulate open drain by not actively driving the line high */
3073 return gpiod_direction_input(desc);
3075 else if (test_bit(FLAG_OPEN_SOURCE, &desc->flags)) {
3076 ret = gpio_set_config(gc, gpio_chip_hwgpio(desc),
3077 PIN_CONFIG_DRIVE_OPEN_SOURCE);
3079 goto set_output_value;
3080 /* Emulate open source by not actively driving the line low */
3082 return gpiod_direction_input(desc);
3084 gpio_set_config(gc, gpio_chip_hwgpio(desc),
3085 PIN_CONFIG_DRIVE_PUSH_PULL);
3089 return gpiod_direction_output_raw_commit(desc, value);
3091 EXPORT_SYMBOL_GPL(gpiod_direction_output);
3094 * gpiod_set_debounce - sets @debounce time for a GPIO
3095 * @desc: descriptor of the GPIO for which to set debounce time
3096 * @debounce: debounce time in microseconds
3099 * 0 on success, %-ENOTSUPP if the controller doesn't support setting the
3102 int gpiod_set_debounce(struct gpio_desc *desc, unsigned debounce)
3104 struct gpio_chip *chip;
3105 unsigned long config;
3107 VALIDATE_DESC(desc);
3108 chip = desc->gdev->chip;
3109 if (!chip->set || !chip->set_config) {
3111 "%s: missing set() or set_config() operations\n",
3116 config = pinconf_to_config_packed(PIN_CONFIG_INPUT_DEBOUNCE, debounce);
3117 return chip->set_config(chip, gpio_chip_hwgpio(desc), config);
3119 EXPORT_SYMBOL_GPL(gpiod_set_debounce);
3122 * gpiod_set_transitory - Lose or retain GPIO state on suspend or reset
3123 * @desc: descriptor of the GPIO for which to configure persistence
3124 * @transitory: True to lose state on suspend or reset, false for persistence
3127 * 0 on success, otherwise a negative error code.
3129 int gpiod_set_transitory(struct gpio_desc *desc, bool transitory)
3131 struct gpio_chip *chip;
3132 unsigned long packed;
3136 VALIDATE_DESC(desc);
3138 * Handle FLAG_TRANSITORY first, enabling queries to gpiolib for
3139 * persistence state.
3142 set_bit(FLAG_TRANSITORY, &desc->flags);
3144 clear_bit(FLAG_TRANSITORY, &desc->flags);
3146 /* If the driver supports it, set the persistence state now */
3147 chip = desc->gdev->chip;
3148 if (!chip->set_config)
3151 packed = pinconf_to_config_packed(PIN_CONFIG_PERSIST_STATE,
3153 gpio = gpio_chip_hwgpio(desc);
3154 rc = chip->set_config(chip, gpio, packed);
3155 if (rc == -ENOTSUPP) {
3156 dev_dbg(&desc->gdev->dev, "Persistence not supported for GPIO %d\n",
3163 EXPORT_SYMBOL_GPL(gpiod_set_transitory);
3166 * gpiod_is_active_low - test whether a GPIO is active-low or not
3167 * @desc: the gpio descriptor to test
3169 * Returns 1 if the GPIO is active-low, 0 otherwise.
3171 int gpiod_is_active_low(const struct gpio_desc *desc)
3173 VALIDATE_DESC(desc);
3174 return test_bit(FLAG_ACTIVE_LOW, &desc->flags);
3176 EXPORT_SYMBOL_GPL(gpiod_is_active_low);
3178 /* I/O calls are only valid after configuration completed; the relevant
3179 * "is this a valid GPIO" error checks should already have been done.
3181 * "Get" operations are often inlinable as reading a pin value register,
3182 * and masking the relevant bit in that register.
3184 * When "set" operations are inlinable, they involve writing that mask to
3185 * one register to set a low value, or a different register to set it high.
3186 * Otherwise locking is needed, so there may be little value to inlining.
3188 *------------------------------------------------------------------------
3190 * IMPORTANT!!! The hot paths -- get/set value -- assume that callers
3191 * have requested the GPIO. That can include implicit requesting by
3192 * a direction setting call. Marking a gpio as requested locks its chip
3193 * in memory, guaranteeing that these table lookups need no more locking
3194 * and that gpiochip_remove() will fail.
3196 * REVISIT when debugging, consider adding some instrumentation to ensure
3197 * that the GPIO was actually requested.
3200 static int gpiod_get_raw_value_commit(const struct gpio_desc *desc)
3202 struct gpio_chip *chip;
3206 chip = desc->gdev->chip;
3207 offset = gpio_chip_hwgpio(desc);
3208 value = chip->get ? chip->get(chip, offset) : -EIO;
3209 value = value < 0 ? value : !!value;
3210 trace_gpio_value(desc_to_gpio(desc), 1, value);
3214 static int gpio_chip_get_multiple(struct gpio_chip *chip,
3215 unsigned long *mask, unsigned long *bits)
3217 if (chip->get_multiple) {
3218 return chip->get_multiple(chip, mask, bits);
3219 } else if (chip->get) {
3222 for_each_set_bit(i, mask, chip->ngpio) {
3223 value = chip->get(chip, i);
3226 __assign_bit(i, bits, value);
3233 int gpiod_get_array_value_complex(bool raw, bool can_sleep,
3234 unsigned int array_size,
3235 struct gpio_desc **desc_array,
3236 struct gpio_array *array_info,
3237 unsigned long *value_bitmap)
3242 * Validate array_info against desc_array and its size.
3243 * It should immediately follow desc_array if both
3244 * have been obtained from the same gpiod_get_array() call.
3246 if (array_info && array_info->desc == desc_array &&
3247 array_size <= array_info->size &&
3248 (void *)array_info == desc_array + array_info->size) {
3250 WARN_ON(array_info->chip->can_sleep);
3252 ret = gpio_chip_get_multiple(array_info->chip,
3253 array_info->get_mask,
3258 if (!raw && !bitmap_empty(array_info->invert_mask, array_size))
3259 bitmap_xor(value_bitmap, value_bitmap,
3260 array_info->invert_mask, array_size);
3262 if (bitmap_full(array_info->get_mask, array_size))
3265 i = find_first_zero_bit(array_info->get_mask, array_size);
3270 while (i < array_size) {
3271 struct gpio_chip *chip = desc_array[i]->gdev->chip;
3272 unsigned long fastpath[2 * BITS_TO_LONGS(FASTPATH_NGPIO)];
3273 unsigned long *mask, *bits;
3276 if (likely(chip->ngpio <= FASTPATH_NGPIO)) {
3279 mask = kmalloc_array(2 * BITS_TO_LONGS(chip->ngpio),
3281 can_sleep ? GFP_KERNEL : GFP_ATOMIC);
3286 bits = mask + BITS_TO_LONGS(chip->ngpio);
3287 bitmap_zero(mask, chip->ngpio);
3290 WARN_ON(chip->can_sleep);
3292 /* collect all inputs belonging to the same chip */
3295 const struct gpio_desc *desc = desc_array[i];
3296 int hwgpio = gpio_chip_hwgpio(desc);
3298 __set_bit(hwgpio, mask);
3302 i = find_next_zero_bit(array_info->get_mask,
3304 } while ((i < array_size) &&
3305 (desc_array[i]->gdev->chip == chip));
3307 ret = gpio_chip_get_multiple(chip, mask, bits);
3309 if (mask != fastpath)
3314 for (j = first; j < i; ) {
3315 const struct gpio_desc *desc = desc_array[j];
3316 int hwgpio = gpio_chip_hwgpio(desc);
3317 int value = test_bit(hwgpio, bits);
3319 if (!raw && test_bit(FLAG_ACTIVE_LOW, &desc->flags))
3321 __assign_bit(j, value_bitmap, value);
3322 trace_gpio_value(desc_to_gpio(desc), 1, value);
3326 j = find_next_zero_bit(array_info->get_mask, i,
3330 if (mask != fastpath)
3337 * gpiod_get_raw_value() - return a gpio's raw value
3338 * @desc: gpio whose value will be returned
3340 * Return the GPIO's raw value, i.e. the value of the physical line disregarding
3341 * its ACTIVE_LOW status, or negative errno on failure.
3343 * This function can be called from contexts where we cannot sleep, and will
3344 * complain if the GPIO chip functions potentially sleep.
3346 int gpiod_get_raw_value(const struct gpio_desc *desc)
3348 VALIDATE_DESC(desc);
3349 /* Should be using gpiod_get_raw_value_cansleep() */
3350 WARN_ON(desc->gdev->chip->can_sleep);
3351 return gpiod_get_raw_value_commit(desc);
3353 EXPORT_SYMBOL_GPL(gpiod_get_raw_value);
3356 * gpiod_get_value() - return a gpio's value
3357 * @desc: gpio whose value will be returned
3359 * Return the GPIO's logical value, i.e. taking the ACTIVE_LOW status into
3360 * account, or negative errno on failure.
3362 * This function can be called from contexts where we cannot sleep, and will
3363 * complain if the GPIO chip functions potentially sleep.
3365 int gpiod_get_value(const struct gpio_desc *desc)
3369 VALIDATE_DESC(desc);
3370 /* Should be using gpiod_get_value_cansleep() */
3371 WARN_ON(desc->gdev->chip->can_sleep);
3373 value = gpiod_get_raw_value_commit(desc);
3377 if (test_bit(FLAG_ACTIVE_LOW, &desc->flags))
3382 EXPORT_SYMBOL_GPL(gpiod_get_value);
3385 * gpiod_get_raw_array_value() - read raw values from an array of GPIOs
3386 * @array_size: number of elements in the descriptor array / value bitmap
3387 * @desc_array: array of GPIO descriptors whose values will be read
3388 * @array_info: information on applicability of fast bitmap processing path
3389 * @value_bitmap: bitmap to store the read values
3391 * Read the raw values of the GPIOs, i.e. the values of the physical lines
3392 * without regard for their ACTIVE_LOW status. Return 0 in case of success,
3393 * else an error code.
3395 * This function can be called from contexts where we cannot sleep,
3396 * and it will complain if the GPIO chip functions potentially sleep.
3398 int gpiod_get_raw_array_value(unsigned int array_size,
3399 struct gpio_desc **desc_array,
3400 struct gpio_array *array_info,
3401 unsigned long *value_bitmap)
3405 return gpiod_get_array_value_complex(true, false, array_size,
3406 desc_array, array_info,
3409 EXPORT_SYMBOL_GPL(gpiod_get_raw_array_value);
3412 * gpiod_get_array_value() - read values from an array of GPIOs
3413 * @array_size: number of elements in the descriptor array / value bitmap
3414 * @desc_array: array of GPIO descriptors whose values will be read
3415 * @array_info: information on applicability of fast bitmap processing path
3416 * @value_bitmap: bitmap to store the read values
3418 * Read the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status
3419 * into account. Return 0 in case of success, else an error code.
3421 * This function can be called from contexts where we cannot sleep,
3422 * and it will complain if the GPIO chip functions potentially sleep.
3424 int gpiod_get_array_value(unsigned int array_size,
3425 struct gpio_desc **desc_array,
3426 struct gpio_array *array_info,
3427 unsigned long *value_bitmap)
3431 return gpiod_get_array_value_complex(false, false, array_size,
3432 desc_array, array_info,
3435 EXPORT_SYMBOL_GPL(gpiod_get_array_value);
3438 * gpio_set_open_drain_value_commit() - Set the open drain gpio's value.
3439 * @desc: gpio descriptor whose state need to be set.
3440 * @value: Non-zero for setting it HIGH otherwise it will set to LOW.
3442 static void gpio_set_open_drain_value_commit(struct gpio_desc *desc, bool value)
3445 struct gpio_chip *chip = desc->gdev->chip;
3446 int offset = gpio_chip_hwgpio(desc);
3449 ret = chip->direction_input(chip, offset);
3451 clear_bit(FLAG_IS_OUT, &desc->flags);
3453 ret = chip->direction_output(chip, offset, 0);
3455 set_bit(FLAG_IS_OUT, &desc->flags);
3457 trace_gpio_direction(desc_to_gpio(desc), value, ret);
3460 "%s: Error in set_value for open drain err %d\n",
3465 * _gpio_set_open_source_value() - Set the open source gpio's value.
3466 * @desc: gpio descriptor whose state need to be set.
3467 * @value: Non-zero for setting it HIGH otherwise it will set to LOW.
3469 static void gpio_set_open_source_value_commit(struct gpio_desc *desc, bool value)
3472 struct gpio_chip *chip = desc->gdev->chip;
3473 int offset = gpio_chip_hwgpio(desc);
3476 ret = chip->direction_output(chip, offset, 1);
3478 set_bit(FLAG_IS_OUT, &desc->flags);
3480 ret = chip->direction_input(chip, offset);
3482 clear_bit(FLAG_IS_OUT, &desc->flags);
3484 trace_gpio_direction(desc_to_gpio(desc), !value, ret);
3487 "%s: Error in set_value for open source err %d\n",
3491 static void gpiod_set_raw_value_commit(struct gpio_desc *desc, bool value)
3493 struct gpio_chip *chip;
3495 chip = desc->gdev->chip;
3496 trace_gpio_value(desc_to_gpio(desc), 0, value);
3497 chip->set(chip, gpio_chip_hwgpio(desc), value);
3501 * set multiple outputs on the same chip;
3502 * use the chip's set_multiple function if available;
3503 * otherwise set the outputs sequentially;
3504 * @mask: bit mask array; one bit per output; BITS_PER_LONG bits per word
3505 * defines which outputs are to be changed
3506 * @bits: bit value array; one bit per output; BITS_PER_LONG bits per word
3507 * defines the values the outputs specified by mask are to be set to
3509 static void gpio_chip_set_multiple(struct gpio_chip *chip,
3510 unsigned long *mask, unsigned long *bits)
3512 if (chip->set_multiple) {
3513 chip->set_multiple(chip, mask, bits);
3517 /* set outputs if the corresponding mask bit is set */
3518 for_each_set_bit(i, mask, chip->ngpio)
3519 chip->set(chip, i, test_bit(i, bits));
3523 int gpiod_set_array_value_complex(bool raw, bool can_sleep,
3524 unsigned int array_size,
3525 struct gpio_desc **desc_array,
3526 struct gpio_array *array_info,
3527 unsigned long *value_bitmap)
3532 * Validate array_info against desc_array and its size.
3533 * It should immediately follow desc_array if both
3534 * have been obtained from the same gpiod_get_array() call.
3536 if (array_info && array_info->desc == desc_array &&
3537 array_size <= array_info->size &&
3538 (void *)array_info == desc_array + array_info->size) {
3540 WARN_ON(array_info->chip->can_sleep);
3542 if (!raw && !bitmap_empty(array_info->invert_mask, array_size))
3543 bitmap_xor(value_bitmap, value_bitmap,
3544 array_info->invert_mask, array_size);
3546 gpio_chip_set_multiple(array_info->chip, array_info->set_mask,
3549 if (bitmap_full(array_info->set_mask, array_size))
3552 i = find_first_zero_bit(array_info->set_mask, array_size);
3557 while (i < array_size) {
3558 struct gpio_chip *chip = desc_array[i]->gdev->chip;
3559 unsigned long fastpath[2 * BITS_TO_LONGS(FASTPATH_NGPIO)];
3560 unsigned long *mask, *bits;
3563 if (likely(chip->ngpio <= FASTPATH_NGPIO)) {
3566 mask = kmalloc_array(2 * BITS_TO_LONGS(chip->ngpio),
3568 can_sleep ? GFP_KERNEL : GFP_ATOMIC);
3573 bits = mask + BITS_TO_LONGS(chip->ngpio);
3574 bitmap_zero(mask, chip->ngpio);
3577 WARN_ON(chip->can_sleep);
3580 struct gpio_desc *desc = desc_array[i];
3581 int hwgpio = gpio_chip_hwgpio(desc);
3582 int value = test_bit(i, value_bitmap);
3585 * Pins applicable for fast input but not for
3586 * fast output processing may have been already
3587 * inverted inside the fast path, skip them.
3589 if (!raw && !(array_info &&
3590 test_bit(i, array_info->invert_mask)) &&
3591 test_bit(FLAG_ACTIVE_LOW, &desc->flags))
3593 trace_gpio_value(desc_to_gpio(desc), 0, value);
3595 * collect all normal outputs belonging to the same chip
3596 * open drain and open source outputs are set individually
3598 if (test_bit(FLAG_OPEN_DRAIN, &desc->flags) && !raw) {
3599 gpio_set_open_drain_value_commit(desc, value);
3600 } else if (test_bit(FLAG_OPEN_SOURCE, &desc->flags) && !raw) {
3601 gpio_set_open_source_value_commit(desc, value);
3603 __set_bit(hwgpio, mask);
3605 __set_bit(hwgpio, bits);
3607 __clear_bit(hwgpio, bits);
3613 i = find_next_zero_bit(array_info->set_mask,
3615 } while ((i < array_size) &&
3616 (desc_array[i]->gdev->chip == chip));
3617 /* push collected bits to outputs */
3619 gpio_chip_set_multiple(chip, mask, bits);
3621 if (mask != fastpath)
3628 * gpiod_set_raw_value() - assign a gpio's raw value
3629 * @desc: gpio whose value will be assigned
3630 * @value: value to assign
3632 * Set the raw value of the GPIO, i.e. the value of its physical line without
3633 * regard for its ACTIVE_LOW status.
3635 * This function can be called from contexts where we cannot sleep, and will
3636 * complain if the GPIO chip functions potentially sleep.
3638 void gpiod_set_raw_value(struct gpio_desc *desc, int value)
3640 VALIDATE_DESC_VOID(desc);
3641 /* Should be using gpiod_set_raw_value_cansleep() */
3642 WARN_ON(desc->gdev->chip->can_sleep);
3643 gpiod_set_raw_value_commit(desc, value);
3645 EXPORT_SYMBOL_GPL(gpiod_set_raw_value);
3648 * gpiod_set_value_nocheck() - set a GPIO line value without checking
3649 * @desc: the descriptor to set the value on
3650 * @value: value to set
3652 * This sets the value of a GPIO line backing a descriptor, applying
3653 * different semantic quirks like active low and open drain/source
3656 static void gpiod_set_value_nocheck(struct gpio_desc *desc, int value)
3658 if (test_bit(FLAG_ACTIVE_LOW, &desc->flags))
3660 if (test_bit(FLAG_OPEN_DRAIN, &desc->flags))
3661 gpio_set_open_drain_value_commit(desc, value);
3662 else if (test_bit(FLAG_OPEN_SOURCE, &desc->flags))
3663 gpio_set_open_source_value_commit(desc, value);
3665 gpiod_set_raw_value_commit(desc, value);
3669 * gpiod_set_value() - assign a gpio's value
3670 * @desc: gpio whose value will be assigned
3671 * @value: value to assign
3673 * Set the logical value of the GPIO, i.e. taking its ACTIVE_LOW,
3674 * OPEN_DRAIN and OPEN_SOURCE flags into account.
3676 * This function can be called from contexts where we cannot sleep, and will
3677 * complain if the GPIO chip functions potentially sleep.
3679 void gpiod_set_value(struct gpio_desc *desc, int value)
3681 VALIDATE_DESC_VOID(desc);
3682 /* Should be using gpiod_set_value_cansleep() */
3683 WARN_ON(desc->gdev->chip->can_sleep);
3684 gpiod_set_value_nocheck(desc, value);
3686 EXPORT_SYMBOL_GPL(gpiod_set_value);
3689 * gpiod_set_raw_array_value() - assign values to an array of GPIOs
3690 * @array_size: number of elements in the descriptor array / value bitmap
3691 * @desc_array: array of GPIO descriptors whose values will be assigned
3692 * @array_info: information on applicability of fast bitmap processing path
3693 * @value_bitmap: bitmap of values to assign
3695 * Set the raw values of the GPIOs, i.e. the values of the physical lines
3696 * without regard for their ACTIVE_LOW status.
3698 * This function can be called from contexts where we cannot sleep, and will
3699 * complain if the GPIO chip functions potentially sleep.
3701 int gpiod_set_raw_array_value(unsigned int array_size,
3702 struct gpio_desc **desc_array,
3703 struct gpio_array *array_info,
3704 unsigned long *value_bitmap)
3708 return gpiod_set_array_value_complex(true, false, array_size,
3709 desc_array, array_info, value_bitmap);
3711 EXPORT_SYMBOL_GPL(gpiod_set_raw_array_value);
3714 * gpiod_set_array_value() - assign values to an array of GPIOs
3715 * @array_size: number of elements in the descriptor array / value bitmap
3716 * @desc_array: array of GPIO descriptors whose values will be assigned
3717 * @array_info: information on applicability of fast bitmap processing path
3718 * @value_bitmap: bitmap of values to assign
3720 * Set the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status
3723 * This function can be called from contexts where we cannot sleep, and will
3724 * complain if the GPIO chip functions potentially sleep.
3726 int gpiod_set_array_value(unsigned int array_size,
3727 struct gpio_desc **desc_array,
3728 struct gpio_array *array_info,
3729 unsigned long *value_bitmap)
3733 return gpiod_set_array_value_complex(false, false, array_size,
3734 desc_array, array_info,
3737 EXPORT_SYMBOL_GPL(gpiod_set_array_value);
3740 * gpiod_cansleep() - report whether gpio value access may sleep
3741 * @desc: gpio to check
3744 int gpiod_cansleep(const struct gpio_desc *desc)
3746 VALIDATE_DESC(desc);
3747 return desc->gdev->chip->can_sleep;
3749 EXPORT_SYMBOL_GPL(gpiod_cansleep);
3752 * gpiod_set_consumer_name() - set the consumer name for the descriptor
3753 * @desc: gpio to set the consumer name on
3754 * @name: the new consumer name
3756 int gpiod_set_consumer_name(struct gpio_desc *desc, const char *name)
3758 VALIDATE_DESC(desc);
3760 name = kstrdup_const(name, GFP_KERNEL);
3765 kfree_const(desc->label);
3766 desc_set_label(desc, name);
3770 EXPORT_SYMBOL_GPL(gpiod_set_consumer_name);
3773 * gpiod_to_irq() - return the IRQ corresponding to a GPIO
3774 * @desc: gpio whose IRQ will be returned (already requested)
3776 * Return the IRQ corresponding to the passed GPIO, or an error code in case of
3779 int gpiod_to_irq(const struct gpio_desc *desc)
3781 struct gpio_chip *chip;
3785 * Cannot VALIDATE_DESC() here as gpiod_to_irq() consumer semantics
3786 * requires this function to not return zero on an invalid descriptor
3787 * but rather a negative error number.
3789 if (!desc || IS_ERR(desc) || !desc->gdev || !desc->gdev->chip)
3792 chip = desc->gdev->chip;
3793 offset = gpio_chip_hwgpio(desc);
3795 int retirq = chip->to_irq(chip, offset);
3797 /* Zero means NO_IRQ */
3805 EXPORT_SYMBOL_GPL(gpiod_to_irq);
3808 * gpiochip_lock_as_irq() - lock a GPIO to be used as IRQ
3809 * @chip: the chip the GPIO to lock belongs to
3810 * @offset: the offset of the GPIO to lock as IRQ
3812 * This is used directly by GPIO drivers that want to lock down
3813 * a certain GPIO line to be used for IRQs.
3815 int gpiochip_lock_as_irq(struct gpio_chip *chip, unsigned int offset)
3817 struct gpio_desc *desc;
3819 desc = gpiochip_get_desc(chip, offset);
3821 return PTR_ERR(desc);
3824 * If it's fast: flush the direction setting if something changed
3827 if (!chip->can_sleep && chip->get_direction) {
3828 int dir = gpiod_get_direction(desc);
3831 chip_err(chip, "%s: cannot get GPIO direction\n",
3837 if (test_bit(FLAG_IS_OUT, &desc->flags)) {
3839 "%s: tried to flag a GPIO set as output for IRQ\n",
3844 set_bit(FLAG_USED_AS_IRQ, &desc->flags);
3845 set_bit(FLAG_IRQ_IS_ENABLED, &desc->flags);
3848 * If the consumer has not set up a label (such as when the
3849 * IRQ is referenced from .to_irq()) we set up a label here
3850 * so it is clear this is used as an interrupt.
3853 desc_set_label(desc, "interrupt");
3857 EXPORT_SYMBOL_GPL(gpiochip_lock_as_irq);
3860 * gpiochip_unlock_as_irq() - unlock a GPIO used as IRQ
3861 * @chip: the chip the GPIO to lock belongs to
3862 * @offset: the offset of the GPIO to lock as IRQ
3864 * This is used directly by GPIO drivers that want to indicate
3865 * that a certain GPIO is no longer used exclusively for IRQ.
3867 void gpiochip_unlock_as_irq(struct gpio_chip *chip, unsigned int offset)
3869 struct gpio_desc *desc;
3871 desc = gpiochip_get_desc(chip, offset);
3875 clear_bit(FLAG_USED_AS_IRQ, &desc->flags);
3876 clear_bit(FLAG_IRQ_IS_ENABLED, &desc->flags);
3878 /* If we only had this marking, erase it */
3879 if (desc->label && !strcmp(desc->label, "interrupt"))
3880 desc_set_label(desc, NULL);
3882 EXPORT_SYMBOL_GPL(gpiochip_unlock_as_irq);
3884 void gpiochip_disable_irq(struct gpio_chip *chip, unsigned int offset)
3886 struct gpio_desc *desc = gpiochip_get_desc(chip, offset);
3888 if (!IS_ERR(desc) &&
3889 !WARN_ON(!test_bit(FLAG_USED_AS_IRQ, &desc->flags)))
3890 clear_bit(FLAG_IRQ_IS_ENABLED, &desc->flags);
3892 EXPORT_SYMBOL_GPL(gpiochip_disable_irq);
3894 void gpiochip_enable_irq(struct gpio_chip *chip, unsigned int offset)
3896 struct gpio_desc *desc = gpiochip_get_desc(chip, offset);
3898 if (!IS_ERR(desc) &&
3899 !WARN_ON(!test_bit(FLAG_USED_AS_IRQ, &desc->flags))) {
3900 WARN_ON(test_bit(FLAG_IS_OUT, &desc->flags));
3901 set_bit(FLAG_IRQ_IS_ENABLED, &desc->flags);
3904 EXPORT_SYMBOL_GPL(gpiochip_enable_irq);
3906 bool gpiochip_line_is_irq(struct gpio_chip *chip, unsigned int offset)
3908 if (offset >= chip->ngpio)
3911 return test_bit(FLAG_USED_AS_IRQ, &chip->gpiodev->descs[offset].flags);
3913 EXPORT_SYMBOL_GPL(gpiochip_line_is_irq);
3915 int gpiochip_reqres_irq(struct gpio_chip *chip, unsigned int offset)
3919 if (!try_module_get(chip->gpiodev->owner))
3922 ret = gpiochip_lock_as_irq(chip, offset);
3924 chip_err(chip, "unable to lock HW IRQ %u for IRQ\n", offset);
3925 module_put(chip->gpiodev->owner);
3930 EXPORT_SYMBOL_GPL(gpiochip_reqres_irq);
3932 void gpiochip_relres_irq(struct gpio_chip *chip, unsigned int offset)
3934 gpiochip_unlock_as_irq(chip, offset);
3935 module_put(chip->gpiodev->owner);
3937 EXPORT_SYMBOL_GPL(gpiochip_relres_irq);
3939 bool gpiochip_line_is_open_drain(struct gpio_chip *chip, unsigned int offset)
3941 if (offset >= chip->ngpio)
3944 return test_bit(FLAG_OPEN_DRAIN, &chip->gpiodev->descs[offset].flags);
3946 EXPORT_SYMBOL_GPL(gpiochip_line_is_open_drain);
3948 bool gpiochip_line_is_open_source(struct gpio_chip *chip, unsigned int offset)
3950 if (offset >= chip->ngpio)
3953 return test_bit(FLAG_OPEN_SOURCE, &chip->gpiodev->descs[offset].flags);
3955 EXPORT_SYMBOL_GPL(gpiochip_line_is_open_source);
3957 bool gpiochip_line_is_persistent(struct gpio_chip *chip, unsigned int offset)
3959 if (offset >= chip->ngpio)
3962 return !test_bit(FLAG_TRANSITORY, &chip->gpiodev->descs[offset].flags);
3964 EXPORT_SYMBOL_GPL(gpiochip_line_is_persistent);
3967 * gpiod_get_raw_value_cansleep() - return a gpio's raw value
3968 * @desc: gpio whose value will be returned
3970 * Return the GPIO's raw value, i.e. the value of the physical line disregarding
3971 * its ACTIVE_LOW status, or negative errno on failure.
3973 * This function is to be called from contexts that can sleep.
3975 int gpiod_get_raw_value_cansleep(const struct gpio_desc *desc)
3977 might_sleep_if(extra_checks);
3978 VALIDATE_DESC(desc);
3979 return gpiod_get_raw_value_commit(desc);
3981 EXPORT_SYMBOL_GPL(gpiod_get_raw_value_cansleep);
3984 * gpiod_get_value_cansleep() - return a gpio's value
3985 * @desc: gpio whose value will be returned
3987 * Return the GPIO's logical value, i.e. taking the ACTIVE_LOW status into
3988 * account, or negative errno on failure.
3990 * This function is to be called from contexts that can sleep.
3992 int gpiod_get_value_cansleep(const struct gpio_desc *desc)
3996 might_sleep_if(extra_checks);
3997 VALIDATE_DESC(desc);
3998 value = gpiod_get_raw_value_commit(desc);
4002 if (test_bit(FLAG_ACTIVE_LOW, &desc->flags))
4007 EXPORT_SYMBOL_GPL(gpiod_get_value_cansleep);
4010 * gpiod_get_raw_array_value_cansleep() - read raw values from an array of GPIOs
4011 * @array_size: number of elements in the descriptor array / value bitmap
4012 * @desc_array: array of GPIO descriptors whose values will be read
4013 * @array_info: information on applicability of fast bitmap processing path
4014 * @value_bitmap: bitmap to store the read values
4016 * Read the raw values of the GPIOs, i.e. the values of the physical lines
4017 * without regard for their ACTIVE_LOW status. Return 0 in case of success,
4018 * else an error code.
4020 * This function is to be called from contexts that can sleep.
4022 int gpiod_get_raw_array_value_cansleep(unsigned int array_size,
4023 struct gpio_desc **desc_array,
4024 struct gpio_array *array_info,
4025 unsigned long *value_bitmap)
4027 might_sleep_if(extra_checks);
4030 return gpiod_get_array_value_complex(true, true, array_size,
4031 desc_array, array_info,
4034 EXPORT_SYMBOL_GPL(gpiod_get_raw_array_value_cansleep);
4037 * gpiod_get_array_value_cansleep() - read values from an array of GPIOs
4038 * @array_size: number of elements in the descriptor array / value bitmap
4039 * @desc_array: array of GPIO descriptors whose values will be read
4040 * @array_info: information on applicability of fast bitmap processing path
4041 * @value_bitmap: bitmap to store the read values
4043 * Read the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status
4044 * into account. Return 0 in case of success, else an error code.
4046 * This function is to be called from contexts that can sleep.
4048 int gpiod_get_array_value_cansleep(unsigned int array_size,
4049 struct gpio_desc **desc_array,
4050 struct gpio_array *array_info,
4051 unsigned long *value_bitmap)
4053 might_sleep_if(extra_checks);
4056 return gpiod_get_array_value_complex(false, true, array_size,
4057 desc_array, array_info,
4060 EXPORT_SYMBOL_GPL(gpiod_get_array_value_cansleep);
4063 * gpiod_set_raw_value_cansleep() - assign a gpio's raw value
4064 * @desc: gpio whose value will be assigned
4065 * @value: value to assign
4067 * Set the raw value of the GPIO, i.e. the value of its physical line without
4068 * regard for its ACTIVE_LOW status.
4070 * This function is to be called from contexts that can sleep.
4072 void gpiod_set_raw_value_cansleep(struct gpio_desc *desc, int value)
4074 might_sleep_if(extra_checks);
4075 VALIDATE_DESC_VOID(desc);
4076 gpiod_set_raw_value_commit(desc, value);
4078 EXPORT_SYMBOL_GPL(gpiod_set_raw_value_cansleep);
4081 * gpiod_set_value_cansleep() - assign a gpio's value
4082 * @desc: gpio whose value will be assigned
4083 * @value: value to assign
4085 * Set the logical value of the GPIO, i.e. taking its ACTIVE_LOW status into
4088 * This function is to be called from contexts that can sleep.
4090 void gpiod_set_value_cansleep(struct gpio_desc *desc, int value)
4092 might_sleep_if(extra_checks);
4093 VALIDATE_DESC_VOID(desc);
4094 gpiod_set_value_nocheck(desc, value);
4096 EXPORT_SYMBOL_GPL(gpiod_set_value_cansleep);
4099 * gpiod_set_raw_array_value_cansleep() - assign values to an array of GPIOs
4100 * @array_size: number of elements in the descriptor array / value bitmap
4101 * @desc_array: array of GPIO descriptors whose values will be assigned
4102 * @array_info: information on applicability of fast bitmap processing path
4103 * @value_bitmap: bitmap of values to assign
4105 * Set the raw values of the GPIOs, i.e. the values of the physical lines
4106 * without regard for their ACTIVE_LOW status.
4108 * This function is to be called from contexts that can sleep.
4110 int gpiod_set_raw_array_value_cansleep(unsigned int array_size,
4111 struct gpio_desc **desc_array,
4112 struct gpio_array *array_info,
4113 unsigned long *value_bitmap)
4115 might_sleep_if(extra_checks);
4118 return gpiod_set_array_value_complex(true, true, array_size, desc_array,
4119 array_info, value_bitmap);
4121 EXPORT_SYMBOL_GPL(gpiod_set_raw_array_value_cansleep);
4124 * gpiod_add_lookup_tables() - register GPIO device consumers
4125 * @tables: list of tables of consumers to register
4126 * @n: number of tables in the list
4128 void gpiod_add_lookup_tables(struct gpiod_lookup_table **tables, size_t n)
4132 mutex_lock(&gpio_lookup_lock);
4134 for (i = 0; i < n; i++)
4135 list_add_tail(&tables[i]->list, &gpio_lookup_list);
4137 mutex_unlock(&gpio_lookup_lock);
4141 * gpiod_set_array_value_cansleep() - assign values to an array of GPIOs
4142 * @array_size: number of elements in the descriptor array / value bitmap
4143 * @desc_array: array of GPIO descriptors whose values will be assigned
4144 * @array_info: information on applicability of fast bitmap processing path
4145 * @value_bitmap: bitmap of values to assign
4147 * Set the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status
4150 * This function is to be called from contexts that can sleep.
4152 int gpiod_set_array_value_cansleep(unsigned int array_size,
4153 struct gpio_desc **desc_array,
4154 struct gpio_array *array_info,
4155 unsigned long *value_bitmap)
4157 might_sleep_if(extra_checks);
4160 return gpiod_set_array_value_complex(false, true, array_size,
4161 desc_array, array_info,
4164 EXPORT_SYMBOL_GPL(gpiod_set_array_value_cansleep);
4167 * gpiod_add_lookup_table() - register GPIO device consumers
4168 * @table: table of consumers to register
4170 void gpiod_add_lookup_table(struct gpiod_lookup_table *table)
4172 mutex_lock(&gpio_lookup_lock);
4174 list_add_tail(&table->list, &gpio_lookup_list);
4176 mutex_unlock(&gpio_lookup_lock);
4178 EXPORT_SYMBOL_GPL(gpiod_add_lookup_table);
4181 * gpiod_remove_lookup_table() - unregister GPIO device consumers
4182 * @table: table of consumers to unregister
4184 void gpiod_remove_lookup_table(struct gpiod_lookup_table *table)
4186 mutex_lock(&gpio_lookup_lock);
4188 list_del(&table->list);
4190 mutex_unlock(&gpio_lookup_lock);
4192 EXPORT_SYMBOL_GPL(gpiod_remove_lookup_table);
4195 * gpiod_add_hogs() - register a set of GPIO hogs from machine code
4196 * @hogs: table of gpio hog entries with a zeroed sentinel at the end
4198 void gpiod_add_hogs(struct gpiod_hog *hogs)
4200 struct gpio_chip *chip;
4201 struct gpiod_hog *hog;
4203 mutex_lock(&gpio_machine_hogs_mutex);
4205 for (hog = &hogs[0]; hog->chip_label; hog++) {
4206 list_add_tail(&hog->list, &gpio_machine_hogs);
4209 * The chip may have been registered earlier, so check if it
4210 * exists and, if so, try to hog the line now.
4212 chip = find_chip_by_name(hog->chip_label);
4214 gpiochip_machine_hog(chip, hog);
4217 mutex_unlock(&gpio_machine_hogs_mutex);
4219 EXPORT_SYMBOL_GPL(gpiod_add_hogs);
4221 static struct gpiod_lookup_table *gpiod_find_lookup_table(struct device *dev)
4223 const char *dev_id = dev ? dev_name(dev) : NULL;
4224 struct gpiod_lookup_table *table;
4226 mutex_lock(&gpio_lookup_lock);
4228 list_for_each_entry(table, &gpio_lookup_list, list) {
4229 if (table->dev_id && dev_id) {
4231 * Valid strings on both ends, must be identical to have
4234 if (!strcmp(table->dev_id, dev_id))
4238 * One of the pointers is NULL, so both must be to have
4241 if (dev_id == table->dev_id)
4248 mutex_unlock(&gpio_lookup_lock);
4252 static struct gpio_desc *gpiod_find(struct device *dev, const char *con_id,
4253 unsigned int idx, unsigned long *flags)
4255 struct gpio_desc *desc = ERR_PTR(-ENOENT);
4256 struct gpiod_lookup_table *table;
4257 struct gpiod_lookup *p;
4259 table = gpiod_find_lookup_table(dev);
4263 for (p = &table->table[0]; p->chip_label; p++) {
4264 struct gpio_chip *chip;
4266 /* idx must always match exactly */
4270 /* If the lookup entry has a con_id, require exact match */
4271 if (p->con_id && (!con_id || strcmp(p->con_id, con_id)))
4274 chip = find_chip_by_name(p->chip_label);
4278 * As the lookup table indicates a chip with
4279 * p->chip_label should exist, assume it may
4280 * still appear later and let the interested
4281 * consumer be probed again or let the Deferred
4282 * Probe infrastructure handle the error.
4284 dev_warn(dev, "cannot find GPIO chip %s, deferring\n",
4286 return ERR_PTR(-EPROBE_DEFER);
4289 if (chip->ngpio <= p->chip_hwnum) {
4291 "requested GPIO %d is out of range [0..%d] for chip %s\n",
4292 idx, chip->ngpio, chip->label);
4293 return ERR_PTR(-EINVAL);
4296 desc = gpiochip_get_desc(chip, p->chip_hwnum);
4305 static int platform_gpio_count(struct device *dev, const char *con_id)
4307 struct gpiod_lookup_table *table;
4308 struct gpiod_lookup *p;
4309 unsigned int count = 0;
4311 table = gpiod_find_lookup_table(dev);
4315 for (p = &table->table[0]; p->chip_label; p++) {
4316 if ((con_id && p->con_id && !strcmp(con_id, p->con_id)) ||
4317 (!con_id && !p->con_id))
4327 * gpiod_count - return the number of GPIOs associated with a device / function
4328 * or -ENOENT if no GPIO has been assigned to the requested function
4329 * @dev: GPIO consumer, can be NULL for system-global GPIOs
4330 * @con_id: function within the GPIO consumer
4332 int gpiod_count(struct device *dev, const char *con_id)
4334 int count = -ENOENT;
4336 if (IS_ENABLED(CONFIG_OF) && dev && dev->of_node)
4337 count = of_gpio_get_count(dev, con_id);
4338 else if (IS_ENABLED(CONFIG_ACPI) && dev && ACPI_HANDLE(dev))
4339 count = acpi_gpio_count(dev, con_id);
4342 count = platform_gpio_count(dev, con_id);
4346 EXPORT_SYMBOL_GPL(gpiod_count);
4349 * gpiod_get - obtain a GPIO for a given GPIO function
4350 * @dev: GPIO consumer, can be NULL for system-global GPIOs
4351 * @con_id: function within the GPIO consumer
4352 * @flags: optional GPIO initialization flags
4354 * Return the GPIO descriptor corresponding to the function con_id of device
4355 * dev, -ENOENT if no GPIO has been assigned to the requested function, or
4356 * another IS_ERR() code if an error occurred while trying to acquire the GPIO.
4358 struct gpio_desc *__must_check gpiod_get(struct device *dev, const char *con_id,
4359 enum gpiod_flags flags)
4361 return gpiod_get_index(dev, con_id, 0, flags);
4363 EXPORT_SYMBOL_GPL(gpiod_get);
4366 * gpiod_get_optional - obtain an optional GPIO for a given GPIO function
4367 * @dev: GPIO consumer, can be NULL for system-global GPIOs
4368 * @con_id: function within the GPIO consumer
4369 * @flags: optional GPIO initialization flags
4371 * This is equivalent to gpiod_get(), except that when no GPIO was assigned to
4372 * the requested function it will return NULL. This is convenient for drivers
4373 * that need to handle optional GPIOs.
4375 struct gpio_desc *__must_check gpiod_get_optional(struct device *dev,
4377 enum gpiod_flags flags)
4379 return gpiod_get_index_optional(dev, con_id, 0, flags);
4381 EXPORT_SYMBOL_GPL(gpiod_get_optional);
4385 * gpiod_configure_flags - helper function to configure a given GPIO
4386 * @desc: gpio whose value will be assigned
4387 * @con_id: function within the GPIO consumer
4388 * @lflags: bitmask of gpio_lookup_flags GPIO_* values - returned from
4389 * of_find_gpio() or of_get_gpio_hog()
4390 * @dflags: gpiod_flags - optional GPIO initialization flags
4392 * Return 0 on success, -ENOENT if no GPIO has been assigned to the
4393 * requested function and/or index, or another IS_ERR() code if an error
4394 * occurred while trying to acquire the GPIO.
4396 int gpiod_configure_flags(struct gpio_desc *desc, const char *con_id,
4397 unsigned long lflags, enum gpiod_flags dflags)
4401 if (lflags & GPIO_ACTIVE_LOW)
4402 set_bit(FLAG_ACTIVE_LOW, &desc->flags);
4404 if (lflags & GPIO_OPEN_DRAIN)
4405 set_bit(FLAG_OPEN_DRAIN, &desc->flags);
4406 else if (dflags & GPIOD_FLAGS_BIT_OPEN_DRAIN) {
4408 * This enforces open drain mode from the consumer side.
4409 * This is necessary for some busses like I2C, but the lookup
4410 * should *REALLY* have specified them as open drain in the
4411 * first place, so print a little warning here.
4413 set_bit(FLAG_OPEN_DRAIN, &desc->flags);
4415 "enforced open drain please flag it properly in DT/ACPI DSDT/board file\n");
4418 if (lflags & GPIO_OPEN_SOURCE)
4419 set_bit(FLAG_OPEN_SOURCE, &desc->flags);
4421 if ((lflags & GPIO_PULL_UP) && (lflags & GPIO_PULL_DOWN)) {
4423 "both pull-up and pull-down enabled, invalid configuration\n");
4427 if (lflags & GPIO_PULL_UP)
4428 set_bit(FLAG_PULL_UP, &desc->flags);
4429 else if (lflags & GPIO_PULL_DOWN)
4430 set_bit(FLAG_PULL_DOWN, &desc->flags);
4432 ret = gpiod_set_transitory(desc, (lflags & GPIO_TRANSITORY));
4436 /* No particular flag request, return here... */
4437 if (!(dflags & GPIOD_FLAGS_BIT_DIR_SET)) {
4438 pr_debug("no flags found for %s\n", con_id);
4443 if (dflags & GPIOD_FLAGS_BIT_DIR_OUT)
4444 ret = gpiod_direction_output(desc,
4445 !!(dflags & GPIOD_FLAGS_BIT_DIR_VAL));
4447 ret = gpiod_direction_input(desc);
4453 * gpiod_get_index - obtain a GPIO from a multi-index GPIO function
4454 * @dev: GPIO consumer, can be NULL for system-global GPIOs
4455 * @con_id: function within the GPIO consumer
4456 * @idx: index of the GPIO to obtain in the consumer
4457 * @flags: optional GPIO initialization flags
4459 * This variant of gpiod_get() allows to access GPIOs other than the first
4460 * defined one for functions that define several GPIOs.
4462 * Return a valid GPIO descriptor, -ENOENT if no GPIO has been assigned to the
4463 * requested function and/or index, or another IS_ERR() code if an error
4464 * occurred while trying to acquire the GPIO.
4466 struct gpio_desc *__must_check gpiod_get_index(struct device *dev,
4469 enum gpiod_flags flags)
4471 unsigned long lookupflags = GPIO_LOOKUP_FLAGS_DEFAULT;
4472 struct gpio_desc *desc = NULL;
4474 /* Maybe we have a device name, maybe not */
4475 const char *devname = dev ? dev_name(dev) : "?";
4477 dev_dbg(dev, "GPIO lookup for consumer %s\n", con_id);
4480 /* Using device tree? */
4481 if (IS_ENABLED(CONFIG_OF) && dev->of_node) {
4482 dev_dbg(dev, "using device tree for GPIO lookup\n");
4483 desc = of_find_gpio(dev, con_id, idx, &lookupflags);
4484 } else if (ACPI_COMPANION(dev)) {
4485 dev_dbg(dev, "using ACPI for GPIO lookup\n");
4486 desc = acpi_find_gpio(dev, con_id, idx, &flags, &lookupflags);
4491 * Either we are not using DT or ACPI, or their lookup did not return
4492 * a result. In that case, use platform lookup as a fallback.
4494 if (!desc || desc == ERR_PTR(-ENOENT)) {
4495 dev_dbg(dev, "using lookup tables for GPIO lookup\n");
4496 desc = gpiod_find(dev, con_id, idx, &lookupflags);
4500 dev_dbg(dev, "No GPIO consumer %s found\n", con_id);
4505 * If a connection label was passed use that, else attempt to use
4506 * the device name as label
4508 ret = gpiod_request(desc, con_id ? con_id : devname);
4510 if (ret == -EBUSY && flags & GPIOD_FLAGS_BIT_NONEXCLUSIVE) {
4512 * This happens when there are several consumers for
4513 * the same GPIO line: we just return here without
4514 * further initialization. It is a bit if a hack.
4515 * This is necessary to support fixed regulators.
4517 * FIXME: Make this more sane and safe.
4519 dev_info(dev, "nonexclusive access to GPIO for %s\n",
4520 con_id ? con_id : devname);
4523 return ERR_PTR(ret);
4527 ret = gpiod_configure_flags(desc, con_id, lookupflags, flags);
4529 dev_dbg(dev, "setup of GPIO %s failed\n", con_id);
4531 return ERR_PTR(ret);
4536 EXPORT_SYMBOL_GPL(gpiod_get_index);
4539 * fwnode_get_named_gpiod - obtain a GPIO from firmware node
4540 * @fwnode: handle of the firmware node
4541 * @propname: name of the firmware property representing the GPIO
4542 * @index: index of the GPIO to obtain for the consumer
4543 * @dflags: GPIO initialization flags
4544 * @label: label to attach to the requested GPIO
4546 * This function can be used for drivers that get their configuration
4547 * from opaque firmware.
4549 * The function properly finds the corresponding GPIO using whatever is the
4550 * underlying firmware interface and then makes sure that the GPIO
4551 * descriptor is requested before it is returned to the caller.
4554 * On successful request the GPIO pin is configured in accordance with
4557 * In case of error an ERR_PTR() is returned.
4559 struct gpio_desc *fwnode_get_named_gpiod(struct fwnode_handle *fwnode,
4560 const char *propname, int index,
4561 enum gpiod_flags dflags,
4564 unsigned long lflags = GPIO_LOOKUP_FLAGS_DEFAULT;
4565 struct gpio_desc *desc = ERR_PTR(-ENODEV);
4569 return ERR_PTR(-EINVAL);
4571 if (is_of_node(fwnode)) {
4572 desc = gpiod_get_from_of_node(to_of_node(fwnode),
4577 } else if (is_acpi_node(fwnode)) {
4578 struct acpi_gpio_info info;
4580 desc = acpi_node_get_gpiod(fwnode, propname, index, &info);
4584 acpi_gpio_update_gpiod_flags(&dflags, &info);
4585 acpi_gpio_update_gpiod_lookup_flags(&lflags, &info);
4588 /* Currently only ACPI takes this path */
4589 ret = gpiod_request(desc, label);
4591 return ERR_PTR(ret);
4593 ret = gpiod_configure_flags(desc, propname, lflags, dflags);
4596 return ERR_PTR(ret);
4601 EXPORT_SYMBOL_GPL(fwnode_get_named_gpiod);
4604 * gpiod_get_index_optional - obtain an optional GPIO from a multi-index GPIO
4606 * @dev: GPIO consumer, can be NULL for system-global GPIOs
4607 * @con_id: function within the GPIO consumer
4608 * @index: index of the GPIO to obtain in the consumer
4609 * @flags: optional GPIO initialization flags
4611 * This is equivalent to gpiod_get_index(), except that when no GPIO with the
4612 * specified index was assigned to the requested function it will return NULL.
4613 * This is convenient for drivers that need to handle optional GPIOs.
4615 struct gpio_desc *__must_check gpiod_get_index_optional(struct device *dev,
4618 enum gpiod_flags flags)
4620 struct gpio_desc *desc;
4622 desc = gpiod_get_index(dev, con_id, index, flags);
4624 if (PTR_ERR(desc) == -ENOENT)
4630 EXPORT_SYMBOL_GPL(gpiod_get_index_optional);
4633 * gpiod_hog - Hog the specified GPIO desc given the provided flags
4634 * @desc: gpio whose value will be assigned
4635 * @name: gpio line name
4636 * @lflags: bitmask of gpio_lookup_flags GPIO_* values - returned from
4637 * of_find_gpio() or of_get_gpio_hog()
4638 * @dflags: gpiod_flags - optional GPIO initialization flags
4640 int gpiod_hog(struct gpio_desc *desc, const char *name,
4641 unsigned long lflags, enum gpiod_flags dflags)
4643 struct gpio_chip *chip;
4644 struct gpio_desc *local_desc;
4648 chip = gpiod_to_chip(desc);
4649 hwnum = gpio_chip_hwgpio(desc);
4651 local_desc = gpiochip_request_own_desc(chip, hwnum, name,
4653 if (IS_ERR(local_desc)) {
4654 ret = PTR_ERR(local_desc);
4655 pr_err("requesting hog GPIO %s (chip %s, offset %d) failed, %d\n",
4656 name, chip->label, hwnum, ret);
4660 /* Mark GPIO as hogged so it can be identified and removed later */
4661 set_bit(FLAG_IS_HOGGED, &desc->flags);
4663 pr_info("GPIO line %d (%s) hogged as %s%s\n",
4664 desc_to_gpio(desc), name,
4665 (dflags&GPIOD_FLAGS_BIT_DIR_OUT) ? "output" : "input",
4666 (dflags&GPIOD_FLAGS_BIT_DIR_OUT) ?
4667 (dflags&GPIOD_FLAGS_BIT_DIR_VAL) ? "/high" : "/low":"");
4673 * gpiochip_free_hogs - Scan gpio-controller chip and release GPIO hog
4674 * @chip: gpio chip to act on
4676 static void gpiochip_free_hogs(struct gpio_chip *chip)
4680 for (id = 0; id < chip->ngpio; id++) {
4681 if (test_bit(FLAG_IS_HOGGED, &chip->gpiodev->descs[id].flags))
4682 gpiochip_free_own_desc(&chip->gpiodev->descs[id]);
4687 * gpiod_get_array - obtain multiple GPIOs from a multi-index GPIO function
4688 * @dev: GPIO consumer, can be NULL for system-global GPIOs
4689 * @con_id: function within the GPIO consumer
4690 * @flags: optional GPIO initialization flags
4692 * This function acquires all the GPIOs defined under a given function.
4694 * Return a struct gpio_descs containing an array of descriptors, -ENOENT if
4695 * no GPIO has been assigned to the requested function, or another IS_ERR()
4696 * code if an error occurred while trying to acquire the GPIOs.
4698 struct gpio_descs *__must_check gpiod_get_array(struct device *dev,
4700 enum gpiod_flags flags)
4702 struct gpio_desc *desc;
4703 struct gpio_descs *descs;
4704 struct gpio_array *array_info = NULL;
4705 struct gpio_chip *chip;
4706 int count, bitmap_size;
4708 count = gpiod_count(dev, con_id);
4710 return ERR_PTR(count);
4712 descs = kzalloc(struct_size(descs, desc, count), GFP_KERNEL);
4714 return ERR_PTR(-ENOMEM);
4716 for (descs->ndescs = 0; descs->ndescs < count; ) {
4717 desc = gpiod_get_index(dev, con_id, descs->ndescs, flags);
4719 gpiod_put_array(descs);
4720 return ERR_CAST(desc);
4723 descs->desc[descs->ndescs] = desc;
4725 chip = gpiod_to_chip(desc);
4727 * If pin hardware number of array member 0 is also 0, select
4728 * its chip as a candidate for fast bitmap processing path.
4730 if (descs->ndescs == 0 && gpio_chip_hwgpio(desc) == 0) {
4731 struct gpio_descs *array;
4733 bitmap_size = BITS_TO_LONGS(chip->ngpio > count ?
4734 chip->ngpio : count);
4736 array = kzalloc(struct_size(descs, desc, count) +
4737 struct_size(array_info, invert_mask,
4738 3 * bitmap_size), GFP_KERNEL);
4740 gpiod_put_array(descs);
4741 return ERR_PTR(-ENOMEM);
4744 memcpy(array, descs,
4745 struct_size(descs, desc, descs->ndescs + 1));
4749 array_info = (void *)(descs->desc + count);
4750 array_info->get_mask = array_info->invert_mask +
4752 array_info->set_mask = array_info->get_mask +
4755 array_info->desc = descs->desc;
4756 array_info->size = count;
4757 array_info->chip = chip;
4758 bitmap_set(array_info->get_mask, descs->ndescs,
4759 count - descs->ndescs);
4760 bitmap_set(array_info->set_mask, descs->ndescs,
4761 count - descs->ndescs);
4762 descs->info = array_info;
4764 /* Unmark array members which don't belong to the 'fast' chip */
4765 if (array_info && array_info->chip != chip) {
4766 __clear_bit(descs->ndescs, array_info->get_mask);
4767 __clear_bit(descs->ndescs, array_info->set_mask);
4770 * Detect array members which belong to the 'fast' chip
4771 * but their pins are not in hardware order.
4773 else if (array_info &&
4774 gpio_chip_hwgpio(desc) != descs->ndescs) {
4776 * Don't use fast path if all array members processed so
4777 * far belong to the same chip as this one but its pin
4778 * hardware number is different from its array index.
4780 if (bitmap_full(array_info->get_mask, descs->ndescs)) {
4783 __clear_bit(descs->ndescs,
4784 array_info->get_mask);
4785 __clear_bit(descs->ndescs,
4786 array_info->set_mask);
4788 } else if (array_info) {
4789 /* Exclude open drain or open source from fast output */
4790 if (gpiochip_line_is_open_drain(chip, descs->ndescs) ||
4791 gpiochip_line_is_open_source(chip, descs->ndescs))
4792 __clear_bit(descs->ndescs,
4793 array_info->set_mask);
4794 /* Identify 'fast' pins which require invertion */
4795 if (gpiod_is_active_low(desc))
4796 __set_bit(descs->ndescs,
4797 array_info->invert_mask);
4804 "GPIO array info: chip=%s, size=%d, get_mask=%lx, set_mask=%lx, invert_mask=%lx\n",
4805 array_info->chip->label, array_info->size,
4806 *array_info->get_mask, *array_info->set_mask,
4807 *array_info->invert_mask);
4810 EXPORT_SYMBOL_GPL(gpiod_get_array);
4813 * gpiod_get_array_optional - obtain multiple GPIOs from a multi-index GPIO
4815 * @dev: GPIO consumer, can be NULL for system-global GPIOs
4816 * @con_id: function within the GPIO consumer
4817 * @flags: optional GPIO initialization flags
4819 * This is equivalent to gpiod_get_array(), except that when no GPIO was
4820 * assigned to the requested function it will return NULL.
4822 struct gpio_descs *__must_check gpiod_get_array_optional(struct device *dev,
4824 enum gpiod_flags flags)
4826 struct gpio_descs *descs;
4828 descs = gpiod_get_array(dev, con_id, flags);
4829 if (IS_ERR(descs) && (PTR_ERR(descs) == -ENOENT))
4834 EXPORT_SYMBOL_GPL(gpiod_get_array_optional);
4837 * gpiod_put - dispose of a GPIO descriptor
4838 * @desc: GPIO descriptor to dispose of
4840 * No descriptor can be used after gpiod_put() has been called on it.
4842 void gpiod_put(struct gpio_desc *desc)
4847 EXPORT_SYMBOL_GPL(gpiod_put);
4850 * gpiod_put_array - dispose of multiple GPIO descriptors
4851 * @descs: struct gpio_descs containing an array of descriptors
4853 void gpiod_put_array(struct gpio_descs *descs)
4857 for (i = 0; i < descs->ndescs; i++)
4858 gpiod_put(descs->desc[i]);
4862 EXPORT_SYMBOL_GPL(gpiod_put_array);
4864 static int __init gpiolib_dev_init(void)
4868 /* Register GPIO sysfs bus */
4869 ret = bus_register(&gpio_bus_type);
4871 pr_err("gpiolib: could not register GPIO bus type\n");
4875 ret = alloc_chrdev_region(&gpio_devt, 0, GPIO_DEV_MAX, "gpiochip");
4877 pr_err("gpiolib: failed to allocate char dev region\n");
4878 bus_unregister(&gpio_bus_type);
4880 gpiolib_initialized = true;
4881 gpiochip_setup_devs();
4885 core_initcall(gpiolib_dev_init);
4887 #ifdef CONFIG_DEBUG_FS
4889 static void gpiolib_dbg_show(struct seq_file *s, struct gpio_device *gdev)
4892 struct gpio_chip *chip = gdev->chip;
4893 unsigned gpio = gdev->base;
4894 struct gpio_desc *gdesc = &gdev->descs[0];
4899 for (i = 0; i < gdev->ngpio; i++, gpio++, gdesc++) {
4900 if (!test_bit(FLAG_REQUESTED, &gdesc->flags)) {
4902 seq_printf(s, " gpio-%-3d (%-20.20s)\n",
4908 gpiod_get_direction(gdesc);
4909 is_out = test_bit(FLAG_IS_OUT, &gdesc->flags);
4910 is_irq = test_bit(FLAG_USED_AS_IRQ, &gdesc->flags);
4911 active_low = test_bit(FLAG_ACTIVE_LOW, &gdesc->flags);
4912 seq_printf(s, " gpio-%-3d (%-20.20s|%-20.20s) %s %s %s%s",
4913 gpio, gdesc->name ? gdesc->name : "", gdesc->label,
4914 is_out ? "out" : "in ",
4915 chip->get ? (chip->get(chip, i) ? "hi" : "lo") : "? ",
4916 is_irq ? "IRQ " : "",
4917 active_low ? "ACTIVE LOW" : "");
4918 seq_printf(s, "\n");
4922 static void *gpiolib_seq_start(struct seq_file *s, loff_t *pos)
4924 unsigned long flags;
4925 struct gpio_device *gdev = NULL;
4926 loff_t index = *pos;
4930 spin_lock_irqsave(&gpio_lock, flags);
4931 list_for_each_entry(gdev, &gpio_devices, list)
4933 spin_unlock_irqrestore(&gpio_lock, flags);
4936 spin_unlock_irqrestore(&gpio_lock, flags);
4941 static void *gpiolib_seq_next(struct seq_file *s, void *v, loff_t *pos)
4943 unsigned long flags;
4944 struct gpio_device *gdev = v;
4947 spin_lock_irqsave(&gpio_lock, flags);
4948 if (list_is_last(&gdev->list, &gpio_devices))
4951 ret = list_entry(gdev->list.next, struct gpio_device, list);
4952 spin_unlock_irqrestore(&gpio_lock, flags);
4960 static void gpiolib_seq_stop(struct seq_file *s, void *v)
4964 static int gpiolib_seq_show(struct seq_file *s, void *v)
4966 struct gpio_device *gdev = v;
4967 struct gpio_chip *chip = gdev->chip;
4968 struct device *parent;
4971 seq_printf(s, "%s%s: (dangling chip)", (char *)s->private,
4972 dev_name(&gdev->dev));
4976 seq_printf(s, "%s%s: GPIOs %d-%d", (char *)s->private,
4977 dev_name(&gdev->dev),
4978 gdev->base, gdev->base + gdev->ngpio - 1);
4979 parent = chip->parent;
4981 seq_printf(s, ", parent: %s/%s",
4982 parent->bus ? parent->bus->name : "no-bus",
4985 seq_printf(s, ", %s", chip->label);
4986 if (chip->can_sleep)
4987 seq_printf(s, ", can sleep");
4988 seq_printf(s, ":\n");
4991 chip->dbg_show(s, chip);
4993 gpiolib_dbg_show(s, gdev);
4998 static const struct seq_operations gpiolib_seq_ops = {
4999 .start = gpiolib_seq_start,
5000 .next = gpiolib_seq_next,
5001 .stop = gpiolib_seq_stop,
5002 .show = gpiolib_seq_show,
5005 static int gpiolib_open(struct inode *inode, struct file *file)
5007 return seq_open(file, &gpiolib_seq_ops);
5010 static const struct file_operations gpiolib_operations = {
5011 .owner = THIS_MODULE,
5012 .open = gpiolib_open,
5014 .llseek = seq_lseek,
5015 .release = seq_release,
5018 static int __init gpiolib_debugfs_init(void)
5020 /* /sys/kernel/debug/gpio */
5021 debugfs_create_file("gpio", S_IFREG | S_IRUGO, NULL, NULL,
5022 &gpiolib_operations);
5025 subsys_initcall(gpiolib_debugfs_init);
5027 #endif /* DEBUG_FS */