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/of_gpio.h>
15 #include <linux/idr.h>
16 #include <linux/slab.h>
17 #include <linux/acpi.h>
18 #include <linux/gpio/driver.h>
19 #include <linux/gpio/machine.h>
20 #include <linux/pinctrl/consumer.h>
21 #include <linux/cdev.h>
23 #include <linux/uaccess.h>
24 #include <linux/compat.h>
25 #include <linux/anon_inodes.h>
26 #include <linux/file.h>
27 #include <linux/kfifo.h>
28 #include <linux/poll.h>
29 #include <linux/timekeeping.h>
30 #include <uapi/linux/gpio.h>
34 #define CREATE_TRACE_POINTS
35 #include <trace/events/gpio.h>
37 /* Implementation infrastructure for GPIO interfaces.
39 * The GPIO programming interface allows for inlining speed-critical
40 * get/set operations for common cases, so that access to SOC-integrated
41 * GPIOs can sometimes cost only an instruction or two per bit.
45 /* When debugging, extend minimal trust to callers and platform code.
46 * Also emit diagnostic messages that may help initial bringup, when
47 * board setup or driver bugs are most common.
49 * Otherwise, minimize overhead in what may be bitbanging codepaths.
52 #define extra_checks 1
54 #define extra_checks 0
57 /* Device and char device-related information */
58 static DEFINE_IDA(gpio_ida);
59 static dev_t gpio_devt;
60 #define GPIO_DEV_MAX 256 /* 256 GPIO chip devices supported */
61 static struct bus_type gpio_bus_type = {
66 * Number of GPIOs to use for the fast path in set array
68 #define FASTPATH_NGPIO CONFIG_GPIOLIB_FASTPATH_LIMIT
70 /* gpio_lock prevents conflicts during gpio_desc[] table updates.
71 * While any GPIO is requested, its gpio_chip is not removable;
72 * each GPIO's "requested" flag serves as a lock and refcount.
74 DEFINE_SPINLOCK(gpio_lock);
76 static DEFINE_MUTEX(gpio_lookup_lock);
77 static LIST_HEAD(gpio_lookup_list);
78 LIST_HEAD(gpio_devices);
80 static DEFINE_MUTEX(gpio_machine_hogs_mutex);
81 static LIST_HEAD(gpio_machine_hogs);
83 static void gpiochip_free_hogs(struct gpio_chip *chip);
84 static int gpiochip_add_irqchip(struct gpio_chip *gpiochip,
85 struct lock_class_key *lock_key,
86 struct lock_class_key *request_key);
87 static void gpiochip_irqchip_remove(struct gpio_chip *gpiochip);
88 static int gpiochip_irqchip_init_valid_mask(struct gpio_chip *gpiochip);
89 static void gpiochip_irqchip_free_valid_mask(struct gpio_chip *gpiochip);
91 static bool gpiolib_initialized;
93 static inline void desc_set_label(struct gpio_desc *d, const char *label)
99 * gpio_to_desc - Convert a GPIO number to its descriptor
100 * @gpio: global GPIO number
103 * The GPIO descriptor associated with the given GPIO, or %NULL if no GPIO
104 * with the given number exists in the system.
106 struct gpio_desc *gpio_to_desc(unsigned gpio)
108 struct gpio_device *gdev;
111 spin_lock_irqsave(&gpio_lock, flags);
113 list_for_each_entry(gdev, &gpio_devices, list) {
114 if (gdev->base <= gpio &&
115 gdev->base + gdev->ngpio > gpio) {
116 spin_unlock_irqrestore(&gpio_lock, flags);
117 return &gdev->descs[gpio - gdev->base];
121 spin_unlock_irqrestore(&gpio_lock, flags);
123 if (!gpio_is_valid(gpio))
124 WARN(1, "invalid GPIO %d\n", gpio);
128 EXPORT_SYMBOL_GPL(gpio_to_desc);
131 * gpiochip_get_desc - get the GPIO descriptor corresponding to the given
132 * hardware number for this chip
134 * @hwnum: hardware number of the GPIO for this chip
137 * A pointer to the GPIO descriptor or %ERR_PTR(-EINVAL) if no GPIO exists
138 * in the given chip for the specified hardware number.
140 struct gpio_desc *gpiochip_get_desc(struct gpio_chip *chip,
143 struct gpio_device *gdev = chip->gpiodev;
145 if (hwnum >= gdev->ngpio)
146 return ERR_PTR(-EINVAL);
148 return &gdev->descs[hwnum];
152 * desc_to_gpio - convert a GPIO descriptor to the integer namespace
153 * @desc: GPIO descriptor
155 * This should disappear in the future but is needed since we still
156 * use GPIO numbers for error messages and sysfs nodes.
159 * The global GPIO number for the GPIO specified by its descriptor.
161 int desc_to_gpio(const struct gpio_desc *desc)
163 return desc->gdev->base + (desc - &desc->gdev->descs[0]);
165 EXPORT_SYMBOL_GPL(desc_to_gpio);
169 * gpiod_to_chip - Return the GPIO chip to which a GPIO descriptor belongs
170 * @desc: descriptor to return the chip of
172 struct gpio_chip *gpiod_to_chip(const struct gpio_desc *desc)
174 if (!desc || !desc->gdev)
176 return desc->gdev->chip;
178 EXPORT_SYMBOL_GPL(gpiod_to_chip);
180 /* dynamic allocation of GPIOs, e.g. on a hotplugged device */
181 static int gpiochip_find_base(int ngpio)
183 struct gpio_device *gdev;
184 int base = ARCH_NR_GPIOS - ngpio;
186 list_for_each_entry_reverse(gdev, &gpio_devices, list) {
187 /* found a free space? */
188 if (gdev->base + gdev->ngpio <= base)
191 /* nope, check the space right before the chip */
192 base = gdev->base - ngpio;
195 if (gpio_is_valid(base)) {
196 pr_debug("%s: found new base at %d\n", __func__, base);
199 pr_err("%s: cannot find free range\n", __func__);
205 * gpiod_get_direction - return the current direction of a GPIO
206 * @desc: GPIO to get the direction of
208 * Returns 0 for output, 1 for input, or an error code in case of error.
210 * This function may sleep if gpiod_cansleep() is true.
212 int gpiod_get_direction(struct gpio_desc *desc)
214 struct gpio_chip *chip;
218 chip = gpiod_to_chip(desc);
219 offset = gpio_chip_hwgpio(desc);
221 if (!chip->get_direction)
224 status = chip->get_direction(chip, offset);
226 /* GPIOF_DIR_IN, or other positive */
228 clear_bit(FLAG_IS_OUT, &desc->flags);
232 set_bit(FLAG_IS_OUT, &desc->flags);
236 EXPORT_SYMBOL_GPL(gpiod_get_direction);
239 * Add a new chip to the global chips list, keeping the list of chips sorted
240 * by range(means [base, base + ngpio - 1]) order.
242 * Return -EBUSY if the new chip overlaps with some other chip's integer
245 static int gpiodev_add_to_list(struct gpio_device *gdev)
247 struct gpio_device *prev, *next;
249 if (list_empty(&gpio_devices)) {
250 /* initial entry in list */
251 list_add_tail(&gdev->list, &gpio_devices);
255 next = list_entry(gpio_devices.next, struct gpio_device, list);
256 if (gdev->base + gdev->ngpio <= next->base) {
257 /* add before first entry */
258 list_add(&gdev->list, &gpio_devices);
262 prev = list_entry(gpio_devices.prev, struct gpio_device, list);
263 if (prev->base + prev->ngpio <= gdev->base) {
264 /* add behind last entry */
265 list_add_tail(&gdev->list, &gpio_devices);
269 list_for_each_entry_safe(prev, next, &gpio_devices, list) {
270 /* at the end of the list */
271 if (&next->list == &gpio_devices)
274 /* add between prev and next */
275 if (prev->base + prev->ngpio <= gdev->base
276 && gdev->base + gdev->ngpio <= next->base) {
277 list_add(&gdev->list, &prev->list);
282 dev_err(&gdev->dev, "GPIO integer space overlap, cannot add chip\n");
287 * Convert a GPIO name to its descriptor
289 static struct gpio_desc *gpio_name_to_desc(const char * const name)
291 struct gpio_device *gdev;
294 spin_lock_irqsave(&gpio_lock, flags);
296 list_for_each_entry(gdev, &gpio_devices, list) {
299 for (i = 0; i != gdev->ngpio; ++i) {
300 struct gpio_desc *desc = &gdev->descs[i];
302 if (!desc->name || !name)
305 if (!strcmp(desc->name, name)) {
306 spin_unlock_irqrestore(&gpio_lock, flags);
312 spin_unlock_irqrestore(&gpio_lock, flags);
318 * Takes the names from gc->names and checks if they are all unique. If they
319 * are, they are assigned to their gpio descriptors.
321 * Warning if one of the names is already used for a different GPIO.
323 static int gpiochip_set_desc_names(struct gpio_chip *gc)
325 struct gpio_device *gdev = gc->gpiodev;
331 /* First check all names if they are unique */
332 for (i = 0; i != gc->ngpio; ++i) {
333 struct gpio_desc *gpio;
335 gpio = gpio_name_to_desc(gc->names[i]);
338 "Detected name collision for GPIO name '%s'\n",
342 /* Then add all names to the GPIO descriptors */
343 for (i = 0; i != gc->ngpio; ++i)
344 gdev->descs[i].name = gc->names[i];
349 static unsigned long *gpiochip_allocate_mask(struct gpio_chip *chip)
353 p = kmalloc_array(BITS_TO_LONGS(chip->ngpio), sizeof(*p), GFP_KERNEL);
357 /* Assume by default all GPIOs are valid */
358 bitmap_fill(p, chip->ngpio);
363 static int gpiochip_alloc_valid_mask(struct gpio_chip *gpiochip)
365 #ifdef CONFIG_OF_GPIO
367 struct device_node *np = gpiochip->of_node;
369 size = of_property_count_u32_elems(np, "gpio-reserved-ranges");
370 if (size > 0 && size % 2 == 0)
371 gpiochip->need_valid_mask = true;
374 if (!gpiochip->need_valid_mask)
377 gpiochip->valid_mask = gpiochip_allocate_mask(gpiochip);
378 if (!gpiochip->valid_mask)
384 static int gpiochip_init_valid_mask(struct gpio_chip *gpiochip)
386 if (gpiochip->init_valid_mask)
387 return gpiochip->init_valid_mask(gpiochip);
392 static void gpiochip_free_valid_mask(struct gpio_chip *gpiochip)
394 kfree(gpiochip->valid_mask);
395 gpiochip->valid_mask = NULL;
398 bool gpiochip_line_is_valid(const struct gpio_chip *gpiochip,
401 /* No mask means all valid */
402 if (likely(!gpiochip->valid_mask))
404 return test_bit(offset, gpiochip->valid_mask);
406 EXPORT_SYMBOL_GPL(gpiochip_line_is_valid);
409 * GPIO line handle management
413 * struct linehandle_state - contains the state of a userspace handle
414 * @gdev: the GPIO device the handle pertains to
415 * @label: consumer label used to tag descriptors
416 * @descs: the GPIO descriptors held by this handle
417 * @numdescs: the number of descriptors held in the descs array
419 struct linehandle_state {
420 struct gpio_device *gdev;
422 struct gpio_desc *descs[GPIOHANDLES_MAX];
426 #define GPIOHANDLE_REQUEST_VALID_FLAGS \
427 (GPIOHANDLE_REQUEST_INPUT | \
428 GPIOHANDLE_REQUEST_OUTPUT | \
429 GPIOHANDLE_REQUEST_ACTIVE_LOW | \
430 GPIOHANDLE_REQUEST_OPEN_DRAIN | \
431 GPIOHANDLE_REQUEST_OPEN_SOURCE)
433 static long linehandle_ioctl(struct file *filep, unsigned int cmd,
436 struct linehandle_state *lh = filep->private_data;
437 void __user *ip = (void __user *)arg;
438 struct gpiohandle_data ghd;
439 DECLARE_BITMAP(vals, GPIOHANDLES_MAX);
442 if (cmd == GPIOHANDLE_GET_LINE_VALUES_IOCTL) {
443 /* NOTE: It's ok to read values of output lines. */
444 int ret = gpiod_get_array_value_complex(false,
453 memset(&ghd, 0, sizeof(ghd));
454 for (i = 0; i < lh->numdescs; i++)
455 ghd.values[i] = test_bit(i, vals);
457 if (copy_to_user(ip, &ghd, sizeof(ghd)))
461 } else if (cmd == GPIOHANDLE_SET_LINE_VALUES_IOCTL) {
463 * All line descriptors were created at once with the same
464 * flags so just check if the first one is really output.
466 if (!test_bit(FLAG_IS_OUT, &lh->descs[0]->flags))
469 if (copy_from_user(&ghd, ip, sizeof(ghd)))
472 /* Clamp all values to [0,1] */
473 for (i = 0; i < lh->numdescs; i++)
474 __assign_bit(i, vals, ghd.values[i]);
476 /* Reuse the array setting function */
477 return gpiod_set_array_value_complex(false,
488 static long linehandle_ioctl_compat(struct file *filep, unsigned int cmd,
491 return linehandle_ioctl(filep, cmd, (unsigned long)compat_ptr(arg));
495 static int linehandle_release(struct inode *inode, struct file *filep)
497 struct linehandle_state *lh = filep->private_data;
498 struct gpio_device *gdev = lh->gdev;
501 for (i = 0; i < lh->numdescs; i++)
502 gpiod_free(lh->descs[i]);
505 put_device(&gdev->dev);
509 static const struct file_operations linehandle_fileops = {
510 .release = linehandle_release,
511 .owner = THIS_MODULE,
512 .llseek = noop_llseek,
513 .unlocked_ioctl = linehandle_ioctl,
515 .compat_ioctl = linehandle_ioctl_compat,
519 static int linehandle_create(struct gpio_device *gdev, void __user *ip)
521 struct gpiohandle_request handlereq;
522 struct linehandle_state *lh;
524 int fd, i, count = 0, ret;
527 if (copy_from_user(&handlereq, ip, sizeof(handlereq)))
529 if ((handlereq.lines == 0) || (handlereq.lines > GPIOHANDLES_MAX))
532 lflags = handlereq.flags;
534 /* Return an error if an unknown flag is set */
535 if (lflags & ~GPIOHANDLE_REQUEST_VALID_FLAGS)
539 * Do not allow both INPUT & OUTPUT flags to be set as they are
542 if ((lflags & GPIOHANDLE_REQUEST_INPUT) &&
543 (lflags & GPIOHANDLE_REQUEST_OUTPUT))
547 * Do not allow OPEN_SOURCE & OPEN_DRAIN flags in a single request. If
548 * the hardware actually supports enabling both at the same time the
549 * electrical result would be disastrous.
551 if ((lflags & GPIOHANDLE_REQUEST_OPEN_DRAIN) &&
552 (lflags & GPIOHANDLE_REQUEST_OPEN_SOURCE))
555 /* OPEN_DRAIN and OPEN_SOURCE flags only make sense for output mode. */
556 if (!(lflags & GPIOHANDLE_REQUEST_OUTPUT) &&
557 ((lflags & GPIOHANDLE_REQUEST_OPEN_DRAIN) ||
558 (lflags & GPIOHANDLE_REQUEST_OPEN_SOURCE)))
561 lh = kzalloc(sizeof(*lh), GFP_KERNEL);
565 get_device(&gdev->dev);
567 /* Make sure this is terminated */
568 handlereq.consumer_label[sizeof(handlereq.consumer_label)-1] = '\0';
569 if (strlen(handlereq.consumer_label)) {
570 lh->label = kstrdup(handlereq.consumer_label,
578 /* Request each GPIO */
579 for (i = 0; i < handlereq.lines; i++) {
580 u32 offset = handlereq.lineoffsets[i];
581 struct gpio_desc *desc;
583 if (offset >= gdev->ngpio) {
588 desc = &gdev->descs[offset];
589 ret = gpiod_request(desc, lh->label);
595 if (lflags & GPIOHANDLE_REQUEST_ACTIVE_LOW)
596 set_bit(FLAG_ACTIVE_LOW, &desc->flags);
597 if (lflags & GPIOHANDLE_REQUEST_OPEN_DRAIN)
598 set_bit(FLAG_OPEN_DRAIN, &desc->flags);
599 if (lflags & GPIOHANDLE_REQUEST_OPEN_SOURCE)
600 set_bit(FLAG_OPEN_SOURCE, &desc->flags);
602 ret = gpiod_set_transitory(desc, false);
607 * Lines have to be requested explicitly for input
608 * or output, else the line will be treated "as is".
610 if (lflags & GPIOHANDLE_REQUEST_OUTPUT) {
611 int val = !!handlereq.default_values[i];
613 ret = gpiod_direction_output(desc, val);
616 } else if (lflags & GPIOHANDLE_REQUEST_INPUT) {
617 ret = gpiod_direction_input(desc);
621 dev_dbg(&gdev->dev, "registered chardev handle for line %d\n",
624 /* Let i point at the last handle */
626 lh->numdescs = handlereq.lines;
628 fd = get_unused_fd_flags(O_RDONLY | O_CLOEXEC);
634 file = anon_inode_getfile("gpio-linehandle",
637 O_RDONLY | O_CLOEXEC);
640 goto out_put_unused_fd;
644 if (copy_to_user(ip, &handlereq, sizeof(handlereq))) {
646 * fput() will trigger the release() callback, so do not go onto
647 * the regular error cleanup path here.
654 fd_install(fd, file);
656 dev_dbg(&gdev->dev, "registered chardev handle for %d lines\n",
664 for (i = 0; i < count; i++)
665 gpiod_free(lh->descs[i]);
669 put_device(&gdev->dev);
674 * GPIO line event management
678 * struct lineevent_state - contains the state of a userspace event
679 * @gdev: the GPIO device the event pertains to
680 * @label: consumer label used to tag descriptors
681 * @desc: the GPIO descriptor held by this event
682 * @eflags: the event flags this line was requested with
683 * @irq: the interrupt that trigger in response to events on this GPIO
684 * @wait: wait queue that handles blocking reads of events
685 * @events: KFIFO for the GPIO events
686 * @read_lock: mutex lock to protect reads from colliding with adding
687 * new events to the FIFO
688 * @timestamp: cache for the timestamp storing it between hardirq
689 * and IRQ thread, used to bring the timestamp close to the actual
692 struct lineevent_state {
693 struct gpio_device *gdev;
695 struct gpio_desc *desc;
698 wait_queue_head_t wait;
699 DECLARE_KFIFO(events, struct gpioevent_data, 16);
700 struct mutex read_lock;
704 #define GPIOEVENT_REQUEST_VALID_FLAGS \
705 (GPIOEVENT_REQUEST_RISING_EDGE | \
706 GPIOEVENT_REQUEST_FALLING_EDGE)
708 static __poll_t lineevent_poll(struct file *filep,
709 struct poll_table_struct *wait)
711 struct lineevent_state *le = filep->private_data;
714 poll_wait(filep, &le->wait, wait);
716 if (!kfifo_is_empty(&le->events))
717 events = EPOLLIN | EPOLLRDNORM;
723 static ssize_t lineevent_read(struct file *filep,
728 struct lineevent_state *le = filep->private_data;
732 if (count < sizeof(struct gpioevent_data))
736 if (kfifo_is_empty(&le->events)) {
737 if (filep->f_flags & O_NONBLOCK)
740 ret = wait_event_interruptible(le->wait,
741 !kfifo_is_empty(&le->events));
746 if (mutex_lock_interruptible(&le->read_lock))
748 ret = kfifo_to_user(&le->events, buf, count, &copied);
749 mutex_unlock(&le->read_lock);
755 * If we couldn't read anything from the fifo (a different
756 * thread might have been faster) we either return -EAGAIN if
757 * the file descriptor is non-blocking, otherwise we go back to
758 * sleep and wait for more data to arrive.
760 if (copied == 0 && (filep->f_flags & O_NONBLOCK))
763 } while (copied == 0);
768 static int lineevent_release(struct inode *inode, struct file *filep)
770 struct lineevent_state *le = filep->private_data;
771 struct gpio_device *gdev = le->gdev;
773 free_irq(le->irq, le);
774 gpiod_free(le->desc);
777 put_device(&gdev->dev);
781 static long lineevent_ioctl(struct file *filep, unsigned int cmd,
784 struct lineevent_state *le = filep->private_data;
785 void __user *ip = (void __user *)arg;
786 struct gpiohandle_data ghd;
789 * We can get the value for an event line but not set it,
790 * because it is input by definition.
792 if (cmd == GPIOHANDLE_GET_LINE_VALUES_IOCTL) {
795 memset(&ghd, 0, sizeof(ghd));
797 val = gpiod_get_value_cansleep(le->desc);
802 if (copy_to_user(ip, &ghd, sizeof(ghd)))
811 static long lineevent_ioctl_compat(struct file *filep, unsigned int cmd,
814 return lineevent_ioctl(filep, cmd, (unsigned long)compat_ptr(arg));
818 static const struct file_operations lineevent_fileops = {
819 .release = lineevent_release,
820 .read = lineevent_read,
821 .poll = lineevent_poll,
822 .owner = THIS_MODULE,
823 .llseek = noop_llseek,
824 .unlocked_ioctl = lineevent_ioctl,
826 .compat_ioctl = lineevent_ioctl_compat,
830 static irqreturn_t lineevent_irq_thread(int irq, void *p)
832 struct lineevent_state *le = p;
833 struct gpioevent_data ge;
836 /* Do not leak kernel stack to userspace */
837 memset(&ge, 0, sizeof(ge));
840 * We may be running from a nested threaded interrupt in which case
841 * we didn't get the timestamp from lineevent_irq_handler().
844 ge.timestamp = ktime_get_real_ns();
846 ge.timestamp = le->timestamp;
848 if (le->eflags & GPIOEVENT_REQUEST_RISING_EDGE
849 && le->eflags & GPIOEVENT_REQUEST_FALLING_EDGE) {
850 int level = gpiod_get_value_cansleep(le->desc);
852 /* Emit low-to-high event */
853 ge.id = GPIOEVENT_EVENT_RISING_EDGE;
855 /* Emit high-to-low event */
856 ge.id = GPIOEVENT_EVENT_FALLING_EDGE;
857 } else if (le->eflags & GPIOEVENT_REQUEST_RISING_EDGE) {
858 /* Emit low-to-high event */
859 ge.id = GPIOEVENT_EVENT_RISING_EDGE;
860 } else if (le->eflags & GPIOEVENT_REQUEST_FALLING_EDGE) {
861 /* Emit high-to-low event */
862 ge.id = GPIOEVENT_EVENT_FALLING_EDGE;
867 ret = kfifo_put(&le->events, ge);
869 wake_up_poll(&le->wait, EPOLLIN);
874 static irqreturn_t lineevent_irq_handler(int irq, void *p)
876 struct lineevent_state *le = p;
879 * Just store the timestamp in hardirq context so we get it as
880 * close in time as possible to the actual event.
882 le->timestamp = ktime_get_real_ns();
884 return IRQ_WAKE_THREAD;
887 static int lineevent_create(struct gpio_device *gdev, void __user *ip)
889 struct gpioevent_request eventreq;
890 struct lineevent_state *le;
891 struct gpio_desc *desc;
900 if (copy_from_user(&eventreq, ip, sizeof(eventreq)))
903 le = kzalloc(sizeof(*le), GFP_KERNEL);
907 get_device(&gdev->dev);
909 /* Make sure this is terminated */
910 eventreq.consumer_label[sizeof(eventreq.consumer_label)-1] = '\0';
911 if (strlen(eventreq.consumer_label)) {
912 le->label = kstrdup(eventreq.consumer_label,
920 offset = eventreq.lineoffset;
921 lflags = eventreq.handleflags;
922 eflags = eventreq.eventflags;
924 if (offset >= gdev->ngpio) {
929 /* Return an error if a unknown flag is set */
930 if ((lflags & ~GPIOHANDLE_REQUEST_VALID_FLAGS) ||
931 (eflags & ~GPIOEVENT_REQUEST_VALID_FLAGS)) {
936 /* This is just wrong: we don't look for events on output lines */
937 if ((lflags & GPIOHANDLE_REQUEST_OUTPUT) ||
938 (lflags & GPIOHANDLE_REQUEST_OPEN_DRAIN) ||
939 (lflags & GPIOHANDLE_REQUEST_OPEN_SOURCE)) {
944 desc = &gdev->descs[offset];
945 ret = gpiod_request(desc, le->label);
951 if (lflags & GPIOHANDLE_REQUEST_ACTIVE_LOW)
952 set_bit(FLAG_ACTIVE_LOW, &desc->flags);
954 ret = gpiod_direction_input(desc);
958 le->irq = gpiod_to_irq(desc);
964 if (eflags & GPIOEVENT_REQUEST_RISING_EDGE)
965 irqflags |= test_bit(FLAG_ACTIVE_LOW, &desc->flags) ?
966 IRQF_TRIGGER_FALLING : IRQF_TRIGGER_RISING;
967 if (eflags & GPIOEVENT_REQUEST_FALLING_EDGE)
968 irqflags |= test_bit(FLAG_ACTIVE_LOW, &desc->flags) ?
969 IRQF_TRIGGER_RISING : IRQF_TRIGGER_FALLING;
970 irqflags |= IRQF_ONESHOT;
972 INIT_KFIFO(le->events);
973 init_waitqueue_head(&le->wait);
974 mutex_init(&le->read_lock);
976 /* Request a thread to read the events */
977 ret = request_threaded_irq(le->irq,
978 lineevent_irq_handler,
979 lineevent_irq_thread,
986 fd = get_unused_fd_flags(O_RDONLY | O_CLOEXEC);
992 file = anon_inode_getfile("gpio-event",
995 O_RDONLY | O_CLOEXEC);
998 goto out_put_unused_fd;
1002 if (copy_to_user(ip, &eventreq, sizeof(eventreq))) {
1004 * fput() will trigger the release() callback, so do not go onto
1005 * the regular error cleanup path here.
1012 fd_install(fd, file);
1019 free_irq(le->irq, le);
1021 gpiod_free(le->desc);
1026 put_device(&gdev->dev);
1031 * gpio_ioctl() - ioctl handler for the GPIO chardev
1033 static long gpio_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
1035 struct gpio_device *gdev = filp->private_data;
1036 struct gpio_chip *chip = gdev->chip;
1037 void __user *ip = (void __user *)arg;
1039 /* We fail any subsequent ioctl():s when the chip is gone */
1043 /* Fill in the struct and pass to userspace */
1044 if (cmd == GPIO_GET_CHIPINFO_IOCTL) {
1045 struct gpiochip_info chipinfo;
1047 memset(&chipinfo, 0, sizeof(chipinfo));
1049 strncpy(chipinfo.name, dev_name(&gdev->dev),
1050 sizeof(chipinfo.name));
1051 chipinfo.name[sizeof(chipinfo.name)-1] = '\0';
1052 strncpy(chipinfo.label, gdev->label,
1053 sizeof(chipinfo.label));
1054 chipinfo.label[sizeof(chipinfo.label)-1] = '\0';
1055 chipinfo.lines = gdev->ngpio;
1056 if (copy_to_user(ip, &chipinfo, sizeof(chipinfo)))
1059 } else if (cmd == GPIO_GET_LINEINFO_IOCTL) {
1060 struct gpioline_info lineinfo;
1061 struct gpio_desc *desc;
1063 if (copy_from_user(&lineinfo, ip, sizeof(lineinfo)))
1065 if (lineinfo.line_offset >= gdev->ngpio)
1068 desc = &gdev->descs[lineinfo.line_offset];
1070 strncpy(lineinfo.name, desc->name,
1071 sizeof(lineinfo.name));
1072 lineinfo.name[sizeof(lineinfo.name)-1] = '\0';
1074 lineinfo.name[0] = '\0';
1077 strncpy(lineinfo.consumer, desc->label,
1078 sizeof(lineinfo.consumer));
1079 lineinfo.consumer[sizeof(lineinfo.consumer)-1] = '\0';
1081 lineinfo.consumer[0] = '\0';
1085 * Userspace only need to know that the kernel is using
1086 * this GPIO so it can't use it.
1089 if (test_bit(FLAG_REQUESTED, &desc->flags) ||
1090 test_bit(FLAG_IS_HOGGED, &desc->flags) ||
1091 test_bit(FLAG_USED_AS_IRQ, &desc->flags) ||
1092 test_bit(FLAG_EXPORT, &desc->flags) ||
1093 test_bit(FLAG_SYSFS, &desc->flags))
1094 lineinfo.flags |= GPIOLINE_FLAG_KERNEL;
1095 if (test_bit(FLAG_IS_OUT, &desc->flags))
1096 lineinfo.flags |= GPIOLINE_FLAG_IS_OUT;
1097 if (test_bit(FLAG_ACTIVE_LOW, &desc->flags))
1098 lineinfo.flags |= GPIOLINE_FLAG_ACTIVE_LOW;
1099 if (test_bit(FLAG_OPEN_DRAIN, &desc->flags))
1100 lineinfo.flags |= (GPIOLINE_FLAG_OPEN_DRAIN |
1101 GPIOLINE_FLAG_IS_OUT);
1102 if (test_bit(FLAG_OPEN_SOURCE, &desc->flags))
1103 lineinfo.flags |= (GPIOLINE_FLAG_OPEN_SOURCE |
1104 GPIOLINE_FLAG_IS_OUT);
1106 if (copy_to_user(ip, &lineinfo, sizeof(lineinfo)))
1109 } else if (cmd == GPIO_GET_LINEHANDLE_IOCTL) {
1110 return linehandle_create(gdev, ip);
1111 } else if (cmd == GPIO_GET_LINEEVENT_IOCTL) {
1112 return lineevent_create(gdev, ip);
1117 #ifdef CONFIG_COMPAT
1118 static long gpio_ioctl_compat(struct file *filp, unsigned int cmd,
1121 return gpio_ioctl(filp, cmd, (unsigned long)compat_ptr(arg));
1126 * gpio_chrdev_open() - open the chardev for ioctl operations
1127 * @inode: inode for this chardev
1128 * @filp: file struct for storing private data
1129 * Returns 0 on success
1131 static int gpio_chrdev_open(struct inode *inode, struct file *filp)
1133 struct gpio_device *gdev = container_of(inode->i_cdev,
1134 struct gpio_device, chrdev);
1136 /* Fail on open if the backing gpiochip is gone */
1139 get_device(&gdev->dev);
1140 filp->private_data = gdev;
1142 return nonseekable_open(inode, filp);
1146 * gpio_chrdev_release() - close chardev after ioctl operations
1147 * @inode: inode for this chardev
1148 * @filp: file struct for storing private data
1149 * Returns 0 on success
1151 static int gpio_chrdev_release(struct inode *inode, struct file *filp)
1153 struct gpio_device *gdev = container_of(inode->i_cdev,
1154 struct gpio_device, chrdev);
1156 put_device(&gdev->dev);
1161 static const struct file_operations gpio_fileops = {
1162 .release = gpio_chrdev_release,
1163 .open = gpio_chrdev_open,
1164 .owner = THIS_MODULE,
1165 .llseek = no_llseek,
1166 .unlocked_ioctl = gpio_ioctl,
1167 #ifdef CONFIG_COMPAT
1168 .compat_ioctl = gpio_ioctl_compat,
1172 static void gpiodevice_release(struct device *dev)
1174 struct gpio_device *gdev = dev_get_drvdata(dev);
1176 list_del(&gdev->list);
1177 ida_simple_remove(&gpio_ida, gdev->id);
1178 kfree_const(gdev->label);
1183 static int gpiochip_setup_dev(struct gpio_device *gdev)
1187 cdev_init(&gdev->chrdev, &gpio_fileops);
1188 gdev->chrdev.owner = THIS_MODULE;
1189 gdev->dev.devt = MKDEV(MAJOR(gpio_devt), gdev->id);
1191 status = cdev_device_add(&gdev->chrdev, &gdev->dev);
1195 chip_dbg(gdev->chip, "added GPIO chardev (%d:%d)\n",
1196 MAJOR(gpio_devt), gdev->id);
1198 status = gpiochip_sysfs_register(gdev);
1200 goto err_remove_device;
1202 /* From this point, the .release() function cleans up gpio_device */
1203 gdev->dev.release = gpiodevice_release;
1204 pr_debug("%s: registered GPIOs %d to %d on device: %s (%s)\n",
1205 __func__, gdev->base, gdev->base + gdev->ngpio - 1,
1206 dev_name(&gdev->dev), gdev->chip->label ? : "generic");
1211 cdev_device_del(&gdev->chrdev, &gdev->dev);
1215 static void gpiochip_machine_hog(struct gpio_chip *chip, struct gpiod_hog *hog)
1217 struct gpio_desc *desc;
1220 desc = gpiochip_get_desc(chip, hog->chip_hwnum);
1222 pr_err("%s: unable to get GPIO desc: %ld\n",
1223 __func__, PTR_ERR(desc));
1227 if (test_bit(FLAG_IS_HOGGED, &desc->flags))
1230 rv = gpiod_hog(desc, hog->line_name, hog->lflags, hog->dflags);
1232 pr_err("%s: unable to hog GPIO line (%s:%u): %d\n",
1233 __func__, chip->label, hog->chip_hwnum, rv);
1236 static void machine_gpiochip_add(struct gpio_chip *chip)
1238 struct gpiod_hog *hog;
1240 mutex_lock(&gpio_machine_hogs_mutex);
1242 list_for_each_entry(hog, &gpio_machine_hogs, list) {
1243 if (!strcmp(chip->label, hog->chip_label))
1244 gpiochip_machine_hog(chip, hog);
1247 mutex_unlock(&gpio_machine_hogs_mutex);
1250 static void gpiochip_setup_devs(void)
1252 struct gpio_device *gdev;
1255 list_for_each_entry(gdev, &gpio_devices, list) {
1256 err = gpiochip_setup_dev(gdev);
1258 pr_err("%s: Failed to initialize gpio device (%d)\n",
1259 dev_name(&gdev->dev), err);
1263 int gpiochip_add_data_with_key(struct gpio_chip *chip, void *data,
1264 struct lock_class_key *lock_key,
1265 struct lock_class_key *request_key)
1267 unsigned long flags;
1270 int base = chip->base;
1271 struct gpio_device *gdev;
1274 * First: allocate and populate the internal stat container, and
1275 * set up the struct device.
1277 gdev = kzalloc(sizeof(*gdev), GFP_KERNEL);
1280 gdev->dev.bus = &gpio_bus_type;
1282 chip->gpiodev = gdev;
1284 gdev->dev.parent = chip->parent;
1285 gdev->dev.of_node = chip->parent->of_node;
1288 #ifdef CONFIG_OF_GPIO
1289 /* If the gpiochip has an assigned OF node this takes precedence */
1291 gdev->dev.of_node = chip->of_node;
1293 chip->of_node = gdev->dev.of_node;
1296 gdev->id = ida_simple_get(&gpio_ida, 0, 0, GFP_KERNEL);
1301 dev_set_name(&gdev->dev, "gpiochip%d", gdev->id);
1302 device_initialize(&gdev->dev);
1303 dev_set_drvdata(&gdev->dev, gdev);
1304 if (chip->parent && chip->parent->driver)
1305 gdev->owner = chip->parent->driver->owner;
1306 else if (chip->owner)
1307 /* TODO: remove chip->owner */
1308 gdev->owner = chip->owner;
1310 gdev->owner = THIS_MODULE;
1312 gdev->descs = kcalloc(chip->ngpio, sizeof(gdev->descs[0]), GFP_KERNEL);
1318 if (chip->ngpio == 0) {
1319 chip_err(chip, "tried to insert a GPIO chip with zero lines\n");
1321 goto err_free_descs;
1324 if (chip->ngpio > FASTPATH_NGPIO)
1325 chip_warn(chip, "line cnt %u is greater than fast path cnt %u\n",
1326 chip->ngpio, FASTPATH_NGPIO);
1328 gdev->label = kstrdup_const(chip->label ?: "unknown", GFP_KERNEL);
1331 goto err_free_descs;
1334 gdev->ngpio = chip->ngpio;
1337 spin_lock_irqsave(&gpio_lock, flags);
1340 * TODO: this allocates a Linux GPIO number base in the global
1341 * GPIO numberspace for this chip. In the long run we want to
1342 * get *rid* of this numberspace and use only descriptors, but
1343 * it may be a pipe dream. It will not happen before we get rid
1344 * of the sysfs interface anyways.
1347 base = gpiochip_find_base(chip->ngpio);
1350 spin_unlock_irqrestore(&gpio_lock, flags);
1351 goto err_free_label;
1354 * TODO: it should not be necessary to reflect the assigned
1355 * base outside of the GPIO subsystem. Go over drivers and
1356 * see if anyone makes use of this, else drop this and assign
1363 status = gpiodev_add_to_list(gdev);
1365 spin_unlock_irqrestore(&gpio_lock, flags);
1366 goto err_free_label;
1369 spin_unlock_irqrestore(&gpio_lock, flags);
1371 for (i = 0; i < chip->ngpio; i++)
1372 gdev->descs[i].gdev = gdev;
1374 #ifdef CONFIG_PINCTRL
1375 INIT_LIST_HEAD(&gdev->pin_ranges);
1378 status = gpiochip_set_desc_names(chip);
1380 goto err_remove_from_list;
1382 status = gpiochip_alloc_valid_mask(chip);
1384 goto err_remove_from_list;
1386 status = of_gpiochip_add(chip);
1388 goto err_free_gpiochip_mask;
1390 status = gpiochip_init_valid_mask(chip);
1392 goto err_remove_of_chip;
1394 for (i = 0; i < chip->ngpio; i++) {
1395 struct gpio_desc *desc = &gdev->descs[i];
1397 if (chip->get_direction && gpiochip_line_is_valid(chip, i)) {
1398 if (!chip->get_direction(chip, i))
1399 set_bit(FLAG_IS_OUT, &desc->flags);
1401 clear_bit(FLAG_IS_OUT, &desc->flags);
1403 if (!chip->direction_input)
1404 set_bit(FLAG_IS_OUT, &desc->flags);
1406 clear_bit(FLAG_IS_OUT, &desc->flags);
1410 acpi_gpiochip_add(chip);
1412 machine_gpiochip_add(chip);
1414 status = gpiochip_irqchip_init_valid_mask(chip);
1416 goto err_remove_acpi_chip;
1418 status = gpiochip_add_irqchip(chip, lock_key, request_key);
1420 goto err_remove_irqchip_mask;
1423 * By first adding the chardev, and then adding the device,
1424 * we get a device node entry in sysfs under
1425 * /sys/bus/gpio/devices/gpiochipN/dev that can be used for
1426 * coldplug of device nodes and other udev business.
1427 * We can do this only if gpiolib has been initialized.
1428 * Otherwise, defer until later.
1430 if (gpiolib_initialized) {
1431 status = gpiochip_setup_dev(gdev);
1433 goto err_remove_irqchip;
1438 gpiochip_irqchip_remove(chip);
1439 err_remove_irqchip_mask:
1440 gpiochip_irqchip_free_valid_mask(chip);
1441 err_remove_acpi_chip:
1442 acpi_gpiochip_remove(chip);
1444 gpiochip_free_hogs(chip);
1445 of_gpiochip_remove(chip);
1446 err_free_gpiochip_mask:
1447 gpiochip_free_valid_mask(chip);
1448 err_remove_from_list:
1449 spin_lock_irqsave(&gpio_lock, flags);
1450 list_del(&gdev->list);
1451 spin_unlock_irqrestore(&gpio_lock, flags);
1453 kfree_const(gdev->label);
1457 ida_simple_remove(&gpio_ida, gdev->id);
1459 /* failures here can mean systems won't boot... */
1460 pr_err("%s: GPIOs %d..%d (%s) failed to register, %d\n", __func__,
1461 gdev->base, gdev->base + gdev->ngpio - 1,
1462 chip->label ? : "generic", status);
1466 EXPORT_SYMBOL_GPL(gpiochip_add_data_with_key);
1469 * gpiochip_get_data() - get per-subdriver data for the chip
1473 * The per-subdriver data for the chip.
1475 void *gpiochip_get_data(struct gpio_chip *chip)
1477 return chip->gpiodev->data;
1479 EXPORT_SYMBOL_GPL(gpiochip_get_data);
1482 * gpiochip_remove() - unregister a gpio_chip
1483 * @chip: the chip to unregister
1485 * A gpio_chip with any GPIOs still requested may not be removed.
1487 void gpiochip_remove(struct gpio_chip *chip)
1489 struct gpio_device *gdev = chip->gpiodev;
1490 struct gpio_desc *desc;
1491 unsigned long flags;
1493 bool requested = false;
1495 /* FIXME: should the legacy sysfs handling be moved to gpio_device? */
1496 gpiochip_sysfs_unregister(gdev);
1497 gpiochip_free_hogs(chip);
1498 /* Numb the device, cancelling all outstanding operations */
1500 gpiochip_irqchip_remove(chip);
1501 acpi_gpiochip_remove(chip);
1502 gpiochip_remove_pin_ranges(chip);
1503 of_gpiochip_remove(chip);
1504 gpiochip_free_valid_mask(chip);
1506 * We accept no more calls into the driver from this point, so
1507 * NULL the driver data pointer
1511 spin_lock_irqsave(&gpio_lock, flags);
1512 for (i = 0; i < gdev->ngpio; i++) {
1513 desc = &gdev->descs[i];
1514 if (test_bit(FLAG_REQUESTED, &desc->flags))
1517 spin_unlock_irqrestore(&gpio_lock, flags);
1520 dev_crit(&gdev->dev,
1521 "REMOVING GPIOCHIP WITH GPIOS STILL REQUESTED\n");
1524 * The gpiochip side puts its use of the device to rest here:
1525 * if there are no userspace clients, the chardev and device will
1526 * be removed, else it will be dangling until the last user is
1529 cdev_device_del(&gdev->chrdev, &gdev->dev);
1530 put_device(&gdev->dev);
1532 EXPORT_SYMBOL_GPL(gpiochip_remove);
1534 static void devm_gpio_chip_release(struct device *dev, void *res)
1536 struct gpio_chip *chip = *(struct gpio_chip **)res;
1538 gpiochip_remove(chip);
1542 * devm_gpiochip_add_data() - Resource manager gpiochip_add_data()
1543 * @dev: pointer to the device that gpio_chip belongs to.
1544 * @chip: the chip to register, with chip->base initialized
1545 * @data: driver-private data associated with this chip
1547 * Context: potentially before irqs will work
1549 * The gpio chip automatically be released when the device is unbound.
1552 * A negative errno if the chip can't be registered, such as because the
1553 * chip->base is invalid or already associated with a different chip.
1554 * Otherwise it returns zero as a success code.
1556 int devm_gpiochip_add_data(struct device *dev, struct gpio_chip *chip,
1559 struct gpio_chip **ptr;
1562 ptr = devres_alloc(devm_gpio_chip_release, sizeof(*ptr),
1567 ret = gpiochip_add_data(chip, data);
1574 devres_add(dev, ptr);
1578 EXPORT_SYMBOL_GPL(devm_gpiochip_add_data);
1581 * gpiochip_find() - iterator for locating a specific gpio_chip
1582 * @data: data to pass to match function
1583 * @match: Callback function to check gpio_chip
1585 * Similar to bus_find_device. It returns a reference to a gpio_chip as
1586 * determined by a user supplied @match callback. The callback should return
1587 * 0 if the device doesn't match and non-zero if it does. If the callback is
1588 * non-zero, this function will return to the caller and not iterate over any
1591 struct gpio_chip *gpiochip_find(void *data,
1592 int (*match)(struct gpio_chip *chip,
1595 struct gpio_device *gdev;
1596 struct gpio_chip *chip = NULL;
1597 unsigned long flags;
1599 spin_lock_irqsave(&gpio_lock, flags);
1600 list_for_each_entry(gdev, &gpio_devices, list)
1601 if (gdev->chip && match(gdev->chip, data)) {
1606 spin_unlock_irqrestore(&gpio_lock, flags);
1610 EXPORT_SYMBOL_GPL(gpiochip_find);
1612 static int gpiochip_match_name(struct gpio_chip *chip, void *data)
1614 const char *name = data;
1616 return !strcmp(chip->label, name);
1619 static struct gpio_chip *find_chip_by_name(const char *name)
1621 return gpiochip_find((void *)name, gpiochip_match_name);
1624 #ifdef CONFIG_GPIOLIB_IRQCHIP
1627 * The following is irqchip helper code for gpiochips.
1630 static int gpiochip_irqchip_init_valid_mask(struct gpio_chip *gpiochip)
1632 if (!gpiochip->irq.need_valid_mask)
1635 gpiochip->irq.valid_mask = gpiochip_allocate_mask(gpiochip);
1636 if (!gpiochip->irq.valid_mask)
1642 static void gpiochip_irqchip_free_valid_mask(struct gpio_chip *gpiochip)
1644 kfree(gpiochip->irq.valid_mask);
1645 gpiochip->irq.valid_mask = NULL;
1648 bool gpiochip_irqchip_irq_valid(const struct gpio_chip *gpiochip,
1649 unsigned int offset)
1651 if (!gpiochip_line_is_valid(gpiochip, offset))
1653 /* No mask means all valid */
1654 if (likely(!gpiochip->irq.valid_mask))
1656 return test_bit(offset, gpiochip->irq.valid_mask);
1658 EXPORT_SYMBOL_GPL(gpiochip_irqchip_irq_valid);
1661 * gpiochip_set_cascaded_irqchip() - connects a cascaded irqchip to a gpiochip
1662 * @gc: the gpiochip to set the irqchip chain to
1663 * @parent_irq: the irq number corresponding to the parent IRQ for this
1665 * @parent_handler: the parent interrupt handler for the accumulated IRQ
1666 * coming out of the gpiochip. If the interrupt is nested rather than
1667 * cascaded, pass NULL in this handler argument
1669 static void gpiochip_set_cascaded_irqchip(struct gpio_chip *gc,
1670 unsigned int parent_irq,
1671 irq_flow_handler_t parent_handler)
1673 struct gpio_irq_chip *girq = &gc->irq;
1674 struct device *dev = &gc->gpiodev->dev;
1676 if (!girq->domain) {
1677 chip_err(gc, "called %s before setting up irqchip\n",
1682 if (parent_handler) {
1683 if (gc->can_sleep) {
1685 "you cannot have chained interrupts on a chip that may sleep\n");
1688 girq->parents = devm_kcalloc(dev, 1,
1689 sizeof(*girq->parents),
1691 if (!girq->parents) {
1692 chip_err(gc, "out of memory allocating parent IRQ\n");
1695 girq->parents[0] = parent_irq;
1696 girq->num_parents = 1;
1698 * The parent irqchip is already using the chip_data for this
1699 * irqchip, so our callbacks simply use the handler_data.
1701 irq_set_chained_handler_and_data(parent_irq, parent_handler,
1707 * gpiochip_set_chained_irqchip() - connects a chained irqchip to a gpiochip
1708 * @gpiochip: the gpiochip to set the irqchip chain to
1709 * @irqchip: the irqchip to chain to the gpiochip
1710 * @parent_irq: the irq number corresponding to the parent IRQ for this
1712 * @parent_handler: the parent interrupt handler for the accumulated IRQ
1713 * coming out of the gpiochip.
1715 void gpiochip_set_chained_irqchip(struct gpio_chip *gpiochip,
1716 struct irq_chip *irqchip,
1717 unsigned int parent_irq,
1718 irq_flow_handler_t parent_handler)
1720 if (gpiochip->irq.threaded) {
1721 chip_err(gpiochip, "tried to chain a threaded gpiochip\n");
1725 gpiochip_set_cascaded_irqchip(gpiochip, parent_irq, parent_handler);
1727 EXPORT_SYMBOL_GPL(gpiochip_set_chained_irqchip);
1730 * gpiochip_set_nested_irqchip() - connects a nested irqchip to a gpiochip
1731 * @gpiochip: the gpiochip to set the irqchip nested handler to
1732 * @irqchip: the irqchip to nest to the gpiochip
1733 * @parent_irq: the irq number corresponding to the parent IRQ for this
1736 void gpiochip_set_nested_irqchip(struct gpio_chip *gpiochip,
1737 struct irq_chip *irqchip,
1738 unsigned int parent_irq)
1740 gpiochip_set_cascaded_irqchip(gpiochip, parent_irq, NULL);
1742 EXPORT_SYMBOL_GPL(gpiochip_set_nested_irqchip);
1745 * gpiochip_irq_map() - maps an IRQ into a GPIO irqchip
1746 * @d: the irqdomain used by this irqchip
1747 * @irq: the global irq number used by this GPIO irqchip irq
1748 * @hwirq: the local IRQ/GPIO line offset on this gpiochip
1750 * This function will set up the mapping for a certain IRQ line on a
1751 * gpiochip by assigning the gpiochip as chip data, and using the irqchip
1752 * stored inside the gpiochip.
1754 int gpiochip_irq_map(struct irq_domain *d, unsigned int irq,
1755 irq_hw_number_t hwirq)
1757 struct gpio_chip *chip = d->host_data;
1760 if (!gpiochip_irqchip_irq_valid(chip, hwirq))
1763 irq_set_chip_data(irq, chip);
1765 * This lock class tells lockdep that GPIO irqs are in a different
1766 * category than their parents, so it won't report false recursion.
1768 irq_set_lockdep_class(irq, chip->irq.lock_key, chip->irq.request_key);
1769 irq_set_chip_and_handler(irq, chip->irq.chip, chip->irq.handler);
1770 /* Chips that use nested thread handlers have them marked */
1771 if (chip->irq.threaded)
1772 irq_set_nested_thread(irq, 1);
1773 irq_set_noprobe(irq);
1775 if (chip->irq.num_parents == 1)
1776 err = irq_set_parent(irq, chip->irq.parents[0]);
1777 else if (chip->irq.map)
1778 err = irq_set_parent(irq, chip->irq.map[hwirq]);
1784 * No set-up of the hardware will happen if IRQ_TYPE_NONE
1785 * is passed as default type.
1787 if (chip->irq.default_type != IRQ_TYPE_NONE)
1788 irq_set_irq_type(irq, chip->irq.default_type);
1792 EXPORT_SYMBOL_GPL(gpiochip_irq_map);
1794 void gpiochip_irq_unmap(struct irq_domain *d, unsigned int irq)
1796 struct gpio_chip *chip = d->host_data;
1798 if (chip->irq.threaded)
1799 irq_set_nested_thread(irq, 0);
1800 irq_set_chip_and_handler(irq, NULL, NULL);
1801 irq_set_chip_data(irq, NULL);
1803 EXPORT_SYMBOL_GPL(gpiochip_irq_unmap);
1805 static const struct irq_domain_ops gpiochip_domain_ops = {
1806 .map = gpiochip_irq_map,
1807 .unmap = gpiochip_irq_unmap,
1808 /* Virtually all GPIO irqchips are twocell:ed */
1809 .xlate = irq_domain_xlate_twocell,
1813 * gpiochip_irq_domain_activate() - Lock a GPIO to be used as an IRQ
1814 * @domain: The IRQ domain used by this IRQ chip
1815 * @data: Outermost irq_data associated with the IRQ
1816 * @reserve: If set, only reserve an interrupt vector instead of assigning one
1818 * This function is a wrapper that calls gpiochip_lock_as_irq() and is to be
1819 * used as the activate function for the &struct irq_domain_ops. The host_data
1820 * for the IRQ domain must be the &struct gpio_chip.
1822 int gpiochip_irq_domain_activate(struct irq_domain *domain,
1823 struct irq_data *data, bool reserve)
1825 struct gpio_chip *chip = domain->host_data;
1827 return gpiochip_lock_as_irq(chip, data->hwirq);
1829 EXPORT_SYMBOL_GPL(gpiochip_irq_domain_activate);
1832 * gpiochip_irq_domain_deactivate() - Unlock a GPIO used as an IRQ
1833 * @domain: The IRQ domain used by this IRQ chip
1834 * @data: Outermost irq_data associated with the IRQ
1836 * This function is a wrapper that will call gpiochip_unlock_as_irq() and is to
1837 * be used as the deactivate function for the &struct irq_domain_ops. The
1838 * host_data for the IRQ domain must be the &struct gpio_chip.
1840 void gpiochip_irq_domain_deactivate(struct irq_domain *domain,
1841 struct irq_data *data)
1843 struct gpio_chip *chip = domain->host_data;
1845 return gpiochip_unlock_as_irq(chip, data->hwirq);
1847 EXPORT_SYMBOL_GPL(gpiochip_irq_domain_deactivate);
1849 static int gpiochip_to_irq(struct gpio_chip *chip, unsigned offset)
1851 if (!gpiochip_irqchip_irq_valid(chip, offset))
1854 return irq_create_mapping(chip->irq.domain, offset);
1857 static int gpiochip_irq_reqres(struct irq_data *d)
1859 struct gpio_chip *chip = irq_data_get_irq_chip_data(d);
1861 return gpiochip_reqres_irq(chip, d->hwirq);
1864 static void gpiochip_irq_relres(struct irq_data *d)
1866 struct gpio_chip *chip = irq_data_get_irq_chip_data(d);
1868 gpiochip_relres_irq(chip, d->hwirq);
1871 static void gpiochip_irq_enable(struct irq_data *d)
1873 struct gpio_chip *chip = irq_data_get_irq_chip_data(d);
1875 gpiochip_enable_irq(chip, d->hwirq);
1876 if (chip->irq.irq_enable)
1877 chip->irq.irq_enable(d);
1879 chip->irq.chip->irq_unmask(d);
1882 static void gpiochip_irq_disable(struct irq_data *d)
1884 struct gpio_chip *chip = irq_data_get_irq_chip_data(d);
1886 if (chip->irq.irq_disable)
1887 chip->irq.irq_disable(d);
1889 chip->irq.chip->irq_mask(d);
1890 gpiochip_disable_irq(chip, d->hwirq);
1893 static void gpiochip_set_irq_hooks(struct gpio_chip *gpiochip)
1895 struct irq_chip *irqchip = gpiochip->irq.chip;
1897 if (!irqchip->irq_request_resources &&
1898 !irqchip->irq_release_resources) {
1899 irqchip->irq_request_resources = gpiochip_irq_reqres;
1900 irqchip->irq_release_resources = gpiochip_irq_relres;
1902 if (WARN_ON(gpiochip->irq.irq_enable))
1904 /* Check if the irqchip already has this hook... */
1905 if (irqchip->irq_enable == gpiochip_irq_enable) {
1907 * ...and if so, give a gentle warning that this is bad
1911 "detected irqchip that is shared with multiple gpiochips: please fix the driver.\n");
1914 gpiochip->irq.irq_enable = irqchip->irq_enable;
1915 gpiochip->irq.irq_disable = irqchip->irq_disable;
1916 irqchip->irq_enable = gpiochip_irq_enable;
1917 irqchip->irq_disable = gpiochip_irq_disable;
1921 * gpiochip_add_irqchip() - adds an IRQ chip to a GPIO chip
1922 * @gpiochip: the GPIO chip to add the IRQ chip to
1923 * @lock_key: lockdep class for IRQ lock
1924 * @request_key: lockdep class for IRQ request
1926 static int gpiochip_add_irqchip(struct gpio_chip *gpiochip,
1927 struct lock_class_key *lock_key,
1928 struct lock_class_key *request_key)
1930 struct irq_chip *irqchip = gpiochip->irq.chip;
1931 const struct irq_domain_ops *ops;
1932 struct device_node *np;
1939 if (gpiochip->irq.parent_handler && gpiochip->can_sleep) {
1940 chip_err(gpiochip, "you cannot have chained interrupts on a chip that may sleep\n");
1944 np = gpiochip->gpiodev->dev.of_node;
1945 type = gpiochip->irq.default_type;
1948 * Specifying a default trigger is a terrible idea if DT or ACPI is
1949 * used to configure the interrupts, as you may end up with
1950 * conflicting triggers. Tell the user, and reset to NONE.
1952 if (WARN(np && type != IRQ_TYPE_NONE,
1953 "%s: Ignoring %u default trigger\n", np->full_name, type))
1954 type = IRQ_TYPE_NONE;
1956 if (has_acpi_companion(gpiochip->parent) && type != IRQ_TYPE_NONE) {
1957 acpi_handle_warn(ACPI_HANDLE(gpiochip->parent),
1958 "Ignoring %u default trigger\n", type);
1959 type = IRQ_TYPE_NONE;
1962 gpiochip->to_irq = gpiochip_to_irq;
1963 gpiochip->irq.default_type = type;
1964 gpiochip->irq.lock_key = lock_key;
1965 gpiochip->irq.request_key = request_key;
1967 if (gpiochip->irq.domain_ops)
1968 ops = gpiochip->irq.domain_ops;
1970 ops = &gpiochip_domain_ops;
1972 gpiochip->irq.domain = irq_domain_add_simple(np, gpiochip->ngpio,
1973 gpiochip->irq.first,
1975 if (!gpiochip->irq.domain)
1978 if (gpiochip->irq.parent_handler) {
1979 void *data = gpiochip->irq.parent_handler_data ?: gpiochip;
1981 for (i = 0; i < gpiochip->irq.num_parents; i++) {
1983 * The parent IRQ chip is already using the chip_data
1984 * for this IRQ chip, so our callbacks simply use the
1987 irq_set_chained_handler_and_data(gpiochip->irq.parents[i],
1988 gpiochip->irq.parent_handler,
1993 gpiochip_set_irq_hooks(gpiochip);
1995 acpi_gpiochip_request_interrupts(gpiochip);
2001 * gpiochip_irqchip_remove() - removes an irqchip added to a gpiochip
2002 * @gpiochip: the gpiochip to remove the irqchip from
2004 * This is called only from gpiochip_remove()
2006 static void gpiochip_irqchip_remove(struct gpio_chip *gpiochip)
2008 struct irq_chip *irqchip = gpiochip->irq.chip;
2009 unsigned int offset;
2011 acpi_gpiochip_free_interrupts(gpiochip);
2013 if (irqchip && gpiochip->irq.parent_handler) {
2014 struct gpio_irq_chip *irq = &gpiochip->irq;
2017 for (i = 0; i < irq->num_parents; i++)
2018 irq_set_chained_handler_and_data(irq->parents[i],
2022 /* Remove all IRQ mappings and delete the domain */
2023 if (gpiochip->irq.domain) {
2026 for (offset = 0; offset < gpiochip->ngpio; offset++) {
2027 if (!gpiochip_irqchip_irq_valid(gpiochip, offset))
2030 irq = irq_find_mapping(gpiochip->irq.domain, offset);
2031 irq_dispose_mapping(irq);
2034 irq_domain_remove(gpiochip->irq.domain);
2038 if (irqchip->irq_request_resources == gpiochip_irq_reqres) {
2039 irqchip->irq_request_resources = NULL;
2040 irqchip->irq_release_resources = NULL;
2042 if (irqchip->irq_enable == gpiochip_irq_enable) {
2043 irqchip->irq_enable = gpiochip->irq.irq_enable;
2044 irqchip->irq_disable = gpiochip->irq.irq_disable;
2047 gpiochip->irq.irq_enable = NULL;
2048 gpiochip->irq.irq_disable = NULL;
2049 gpiochip->irq.chip = NULL;
2051 gpiochip_irqchip_free_valid_mask(gpiochip);
2055 * gpiochip_irqchip_add_key() - adds an irqchip to a gpiochip
2056 * @gpiochip: the gpiochip to add the irqchip to
2057 * @irqchip: the irqchip to add to the gpiochip
2058 * @first_irq: if not dynamically assigned, the base (first) IRQ to
2059 * allocate gpiochip irqs from
2060 * @handler: the irq handler to use (often a predefined irq core function)
2061 * @type: the default type for IRQs on this irqchip, pass IRQ_TYPE_NONE
2062 * to have the core avoid setting up any default type in the hardware.
2063 * @threaded: whether this irqchip uses a nested thread handler
2064 * @lock_key: lockdep class for IRQ lock
2065 * @request_key: lockdep class for IRQ request
2067 * This function closely associates a certain irqchip with a certain
2068 * gpiochip, providing an irq domain to translate the local IRQs to
2069 * global irqs in the gpiolib core, and making sure that the gpiochip
2070 * is passed as chip data to all related functions. Driver callbacks
2071 * need to use gpiochip_get_data() to get their local state containers back
2072 * from the gpiochip passed as chip data. An irqdomain will be stored
2073 * in the gpiochip that shall be used by the driver to handle IRQ number
2074 * translation. The gpiochip will need to be initialized and registered
2075 * before calling this function.
2077 * This function will handle two cell:ed simple IRQs and assumes all
2078 * the pins on the gpiochip can generate a unique IRQ. Everything else
2079 * need to be open coded.
2081 int gpiochip_irqchip_add_key(struct gpio_chip *gpiochip,
2082 struct irq_chip *irqchip,
2083 unsigned int first_irq,
2084 irq_flow_handler_t handler,
2087 struct lock_class_key *lock_key,
2088 struct lock_class_key *request_key)
2090 struct device_node *of_node;
2092 if (!gpiochip || !irqchip)
2095 if (!gpiochip->parent) {
2096 pr_err("missing gpiochip .dev parent pointer\n");
2099 gpiochip->irq.threaded = threaded;
2100 of_node = gpiochip->parent->of_node;
2101 #ifdef CONFIG_OF_GPIO
2103 * If the gpiochip has an assigned OF node this takes precedence
2104 * FIXME: get rid of this and use gpiochip->parent->of_node
2107 if (gpiochip->of_node)
2108 of_node = gpiochip->of_node;
2111 * Specifying a default trigger is a terrible idea if DT or ACPI is
2112 * used to configure the interrupts, as you may end-up with
2113 * conflicting triggers. Tell the user, and reset to NONE.
2115 if (WARN(of_node && type != IRQ_TYPE_NONE,
2116 "%pOF: Ignoring %d default trigger\n", of_node, type))
2117 type = IRQ_TYPE_NONE;
2118 if (has_acpi_companion(gpiochip->parent) && type != IRQ_TYPE_NONE) {
2119 acpi_handle_warn(ACPI_HANDLE(gpiochip->parent),
2120 "Ignoring %d default trigger\n", type);
2121 type = IRQ_TYPE_NONE;
2124 gpiochip->irq.chip = irqchip;
2125 gpiochip->irq.handler = handler;
2126 gpiochip->irq.default_type = type;
2127 gpiochip->to_irq = gpiochip_to_irq;
2128 gpiochip->irq.lock_key = lock_key;
2129 gpiochip->irq.request_key = request_key;
2130 gpiochip->irq.domain = irq_domain_add_simple(of_node,
2131 gpiochip->ngpio, first_irq,
2132 &gpiochip_domain_ops, gpiochip);
2133 if (!gpiochip->irq.domain) {
2134 gpiochip->irq.chip = NULL;
2138 gpiochip_set_irq_hooks(gpiochip);
2140 acpi_gpiochip_request_interrupts(gpiochip);
2144 EXPORT_SYMBOL_GPL(gpiochip_irqchip_add_key);
2146 #else /* CONFIG_GPIOLIB_IRQCHIP */
2148 static inline int gpiochip_add_irqchip(struct gpio_chip *gpiochip,
2149 struct lock_class_key *lock_key,
2150 struct lock_class_key *request_key)
2155 static void gpiochip_irqchip_remove(struct gpio_chip *gpiochip) {}
2156 static inline int gpiochip_irqchip_init_valid_mask(struct gpio_chip *gpiochip)
2160 static inline void gpiochip_irqchip_free_valid_mask(struct gpio_chip *gpiochip)
2163 #endif /* CONFIG_GPIOLIB_IRQCHIP */
2166 * gpiochip_generic_request() - request the gpio function for a pin
2167 * @chip: the gpiochip owning the GPIO
2168 * @offset: the offset of the GPIO to request for GPIO function
2170 int gpiochip_generic_request(struct gpio_chip *chip, unsigned offset)
2172 return pinctrl_gpio_request(chip->gpiodev->base + offset);
2174 EXPORT_SYMBOL_GPL(gpiochip_generic_request);
2177 * gpiochip_generic_free() - free the gpio function from a pin
2178 * @chip: the gpiochip to request the gpio function for
2179 * @offset: the offset of the GPIO to free from GPIO function
2181 void gpiochip_generic_free(struct gpio_chip *chip, unsigned offset)
2183 pinctrl_gpio_free(chip->gpiodev->base + offset);
2185 EXPORT_SYMBOL_GPL(gpiochip_generic_free);
2188 * gpiochip_generic_config() - apply configuration for a pin
2189 * @chip: the gpiochip owning the GPIO
2190 * @offset: the offset of the GPIO to apply the configuration
2191 * @config: the configuration to be applied
2193 int gpiochip_generic_config(struct gpio_chip *chip, unsigned offset,
2194 unsigned long config)
2196 return pinctrl_gpio_set_config(chip->gpiodev->base + offset, config);
2198 EXPORT_SYMBOL_GPL(gpiochip_generic_config);
2200 #ifdef CONFIG_PINCTRL
2203 * gpiochip_add_pingroup_range() - add a range for GPIO <-> pin mapping
2204 * @chip: the gpiochip to add the range for
2205 * @pctldev: the pin controller to map to
2206 * @gpio_offset: the start offset in the current gpio_chip number space
2207 * @pin_group: name of the pin group inside the pin controller
2209 * Calling this function directly from a DeviceTree-supported
2210 * pinctrl driver is DEPRECATED. Please see Section 2.1 of
2211 * Documentation/devicetree/bindings/gpio/gpio.txt on how to
2212 * bind pinctrl and gpio drivers via the "gpio-ranges" property.
2214 int gpiochip_add_pingroup_range(struct gpio_chip *chip,
2215 struct pinctrl_dev *pctldev,
2216 unsigned int gpio_offset, const char *pin_group)
2218 struct gpio_pin_range *pin_range;
2219 struct gpio_device *gdev = chip->gpiodev;
2222 pin_range = kzalloc(sizeof(*pin_range), GFP_KERNEL);
2224 chip_err(chip, "failed to allocate pin ranges\n");
2228 /* Use local offset as range ID */
2229 pin_range->range.id = gpio_offset;
2230 pin_range->range.gc = chip;
2231 pin_range->range.name = chip->label;
2232 pin_range->range.base = gdev->base + gpio_offset;
2233 pin_range->pctldev = pctldev;
2235 ret = pinctrl_get_group_pins(pctldev, pin_group,
2236 &pin_range->range.pins,
2237 &pin_range->range.npins);
2243 pinctrl_add_gpio_range(pctldev, &pin_range->range);
2245 chip_dbg(chip, "created GPIO range %d->%d ==> %s PINGRP %s\n",
2246 gpio_offset, gpio_offset + pin_range->range.npins - 1,
2247 pinctrl_dev_get_devname(pctldev), pin_group);
2249 list_add_tail(&pin_range->node, &gdev->pin_ranges);
2253 EXPORT_SYMBOL_GPL(gpiochip_add_pingroup_range);
2256 * gpiochip_add_pin_range() - add a range for GPIO <-> pin mapping
2257 * @chip: the gpiochip to add the range for
2258 * @pinctl_name: the dev_name() of the pin controller to map to
2259 * @gpio_offset: the start offset in the current gpio_chip number space
2260 * @pin_offset: the start offset in the pin controller number space
2261 * @npins: the number of pins from the offset of each pin space (GPIO and
2262 * pin controller) to accumulate in this range
2265 * 0 on success, or a negative error-code on failure.
2267 * Calling this function directly from a DeviceTree-supported
2268 * pinctrl driver is DEPRECATED. Please see Section 2.1 of
2269 * Documentation/devicetree/bindings/gpio/gpio.txt on how to
2270 * bind pinctrl and gpio drivers via the "gpio-ranges" property.
2272 int gpiochip_add_pin_range(struct gpio_chip *chip, const char *pinctl_name,
2273 unsigned int gpio_offset, unsigned int pin_offset,
2276 struct gpio_pin_range *pin_range;
2277 struct gpio_device *gdev = chip->gpiodev;
2280 pin_range = kzalloc(sizeof(*pin_range), GFP_KERNEL);
2282 chip_err(chip, "failed to allocate pin ranges\n");
2286 /* Use local offset as range ID */
2287 pin_range->range.id = gpio_offset;
2288 pin_range->range.gc = chip;
2289 pin_range->range.name = chip->label;
2290 pin_range->range.base = gdev->base + gpio_offset;
2291 pin_range->range.pin_base = pin_offset;
2292 pin_range->range.npins = npins;
2293 pin_range->pctldev = pinctrl_find_and_add_gpio_range(pinctl_name,
2295 if (IS_ERR(pin_range->pctldev)) {
2296 ret = PTR_ERR(pin_range->pctldev);
2297 chip_err(chip, "could not create pin range\n");
2301 chip_dbg(chip, "created GPIO range %d->%d ==> %s PIN %d->%d\n",
2302 gpio_offset, gpio_offset + npins - 1,
2304 pin_offset, pin_offset + npins - 1);
2306 list_add_tail(&pin_range->node, &gdev->pin_ranges);
2310 EXPORT_SYMBOL_GPL(gpiochip_add_pin_range);
2313 * gpiochip_remove_pin_ranges() - remove all the GPIO <-> pin mappings
2314 * @chip: the chip to remove all the mappings for
2316 void gpiochip_remove_pin_ranges(struct gpio_chip *chip)
2318 struct gpio_pin_range *pin_range, *tmp;
2319 struct gpio_device *gdev = chip->gpiodev;
2321 list_for_each_entry_safe(pin_range, tmp, &gdev->pin_ranges, node) {
2322 list_del(&pin_range->node);
2323 pinctrl_remove_gpio_range(pin_range->pctldev,
2328 EXPORT_SYMBOL_GPL(gpiochip_remove_pin_ranges);
2330 #endif /* CONFIG_PINCTRL */
2332 /* These "optional" allocation calls help prevent drivers from stomping
2333 * on each other, and help provide better diagnostics in debugfs.
2334 * They're called even less than the "set direction" calls.
2336 static int gpiod_request_commit(struct gpio_desc *desc, const char *label)
2338 struct gpio_chip *chip = desc->gdev->chip;
2340 unsigned long flags;
2344 label = kstrdup_const(label, GFP_KERNEL);
2349 spin_lock_irqsave(&gpio_lock, flags);
2351 /* NOTE: gpio_request() can be called in early boot,
2352 * before IRQs are enabled, for non-sleeping (SOC) GPIOs.
2355 if (test_and_set_bit(FLAG_REQUESTED, &desc->flags) == 0) {
2356 desc_set_label(desc, label ? : "?");
2364 if (chip->request) {
2365 /* chip->request may sleep */
2366 spin_unlock_irqrestore(&gpio_lock, flags);
2367 offset = gpio_chip_hwgpio(desc);
2368 if (gpiochip_line_is_valid(chip, offset))
2369 status = chip->request(chip, offset);
2372 spin_lock_irqsave(&gpio_lock, flags);
2375 desc_set_label(desc, NULL);
2377 clear_bit(FLAG_REQUESTED, &desc->flags);
2381 if (chip->get_direction) {
2382 /* chip->get_direction may sleep */
2383 spin_unlock_irqrestore(&gpio_lock, flags);
2384 gpiod_get_direction(desc);
2385 spin_lock_irqsave(&gpio_lock, flags);
2388 spin_unlock_irqrestore(&gpio_lock, flags);
2393 * This descriptor validation needs to be inserted verbatim into each
2394 * function taking a descriptor, so we need to use a preprocessor
2395 * macro to avoid endless duplication. If the desc is NULL it is an
2396 * optional GPIO and calls should just bail out.
2398 static int validate_desc(const struct gpio_desc *desc, const char *func)
2403 pr_warn("%s: invalid GPIO (errorpointer)\n", func);
2404 return PTR_ERR(desc);
2407 pr_warn("%s: invalid GPIO (no device)\n", func);
2410 if (!desc->gdev->chip) {
2411 dev_warn(&desc->gdev->dev,
2412 "%s: backing chip is gone\n", func);
2418 #define VALIDATE_DESC(desc) do { \
2419 int __valid = validate_desc(desc, __func__); \
2424 #define VALIDATE_DESC_VOID(desc) do { \
2425 int __valid = validate_desc(desc, __func__); \
2430 int gpiod_request(struct gpio_desc *desc, const char *label)
2432 int status = -EPROBE_DEFER;
2433 struct gpio_device *gdev;
2435 VALIDATE_DESC(desc);
2438 if (try_module_get(gdev->owner)) {
2439 status = gpiod_request_commit(desc, label);
2441 module_put(gdev->owner);
2443 get_device(&gdev->dev);
2447 gpiod_dbg(desc, "%s: status %d\n", __func__, status);
2452 static bool gpiod_free_commit(struct gpio_desc *desc)
2455 unsigned long flags;
2456 struct gpio_chip *chip;
2460 gpiod_unexport(desc);
2462 spin_lock_irqsave(&gpio_lock, flags);
2464 chip = desc->gdev->chip;
2465 if (chip && test_bit(FLAG_REQUESTED, &desc->flags)) {
2467 spin_unlock_irqrestore(&gpio_lock, flags);
2468 might_sleep_if(chip->can_sleep);
2469 chip->free(chip, gpio_chip_hwgpio(desc));
2470 spin_lock_irqsave(&gpio_lock, flags);
2472 kfree_const(desc->label);
2473 desc_set_label(desc, NULL);
2474 clear_bit(FLAG_ACTIVE_LOW, &desc->flags);
2475 clear_bit(FLAG_REQUESTED, &desc->flags);
2476 clear_bit(FLAG_OPEN_DRAIN, &desc->flags);
2477 clear_bit(FLAG_OPEN_SOURCE, &desc->flags);
2478 clear_bit(FLAG_IS_HOGGED, &desc->flags);
2482 spin_unlock_irqrestore(&gpio_lock, flags);
2486 void gpiod_free(struct gpio_desc *desc)
2488 if (desc && desc->gdev && gpiod_free_commit(desc)) {
2489 module_put(desc->gdev->owner);
2490 put_device(&desc->gdev->dev);
2492 WARN_ON(extra_checks);
2497 * gpiochip_is_requested - return string iff signal was requested
2498 * @chip: controller managing the signal
2499 * @offset: of signal within controller's 0..(ngpio - 1) range
2501 * Returns NULL if the GPIO is not currently requested, else a string.
2502 * The string returned is the label passed to gpio_request(); if none has been
2503 * passed it is a meaningless, non-NULL constant.
2505 * This function is for use by GPIO controller drivers. The label can
2506 * help with diagnostics, and knowing that the signal is used as a GPIO
2507 * can help avoid accidentally multiplexing it to another controller.
2509 const char *gpiochip_is_requested(struct gpio_chip *chip, unsigned offset)
2511 struct gpio_desc *desc;
2513 if (offset >= chip->ngpio)
2516 desc = &chip->gpiodev->descs[offset];
2518 if (test_bit(FLAG_REQUESTED, &desc->flags) == 0)
2522 EXPORT_SYMBOL_GPL(gpiochip_is_requested);
2525 * gpiochip_request_own_desc - Allow GPIO chip to request its own descriptor
2527 * @hwnum: hardware number of the GPIO for which to request the descriptor
2528 * @label: label for the GPIO
2529 * @lflags: lookup flags for this GPIO or 0 if default, this can be used to
2530 * specify things like line inversion semantics with the machine flags
2531 * such as GPIO_OUT_LOW
2532 * @dflags: descriptor request flags for this GPIO or 0 if default, this
2533 * can be used to specify consumer semantics such as open drain
2535 * Function allows GPIO chip drivers to request and use their own GPIO
2536 * descriptors via gpiolib API. Difference to gpiod_request() is that this
2537 * function will not increase reference count of the GPIO chip module. This
2538 * allows the GPIO chip module to be unloaded as needed (we assume that the
2539 * GPIO chip driver handles freeing the GPIOs it has requested).
2542 * A pointer to the GPIO descriptor, or an ERR_PTR()-encoded negative error
2545 struct gpio_desc *gpiochip_request_own_desc(struct gpio_chip *chip, u16 hwnum,
2547 enum gpio_lookup_flags lflags,
2548 enum gpiod_flags dflags)
2550 struct gpio_desc *desc = gpiochip_get_desc(chip, hwnum);
2554 chip_err(chip, "failed to get GPIO descriptor\n");
2558 err = gpiod_request_commit(desc, label);
2560 return ERR_PTR(err);
2562 err = gpiod_configure_flags(desc, label, lflags, dflags);
2564 chip_err(chip, "setup of own GPIO %s failed\n", label);
2565 gpiod_free_commit(desc);
2566 return ERR_PTR(err);
2571 EXPORT_SYMBOL_GPL(gpiochip_request_own_desc);
2574 * gpiochip_free_own_desc - Free GPIO requested by the chip driver
2575 * @desc: GPIO descriptor to free
2577 * Function frees the given GPIO requested previously with
2578 * gpiochip_request_own_desc().
2580 void gpiochip_free_own_desc(struct gpio_desc *desc)
2583 gpiod_free_commit(desc);
2585 EXPORT_SYMBOL_GPL(gpiochip_free_own_desc);
2588 * Drivers MUST set GPIO direction before making get/set calls. In
2589 * some cases this is done in early boot, before IRQs are enabled.
2591 * As a rule these aren't called more than once (except for drivers
2592 * using the open-drain emulation idiom) so these are natural places
2593 * to accumulate extra debugging checks. Note that we can't (yet)
2594 * rely on gpio_request() having been called beforehand.
2597 static int gpio_set_config(struct gpio_chip *gc, unsigned offset,
2598 enum pin_config_param mode)
2600 unsigned long config;
2604 case PIN_CONFIG_BIAS_PULL_DOWN:
2605 case PIN_CONFIG_BIAS_PULL_UP:
2613 config = PIN_CONF_PACKED(mode, arg);
2614 return gc->set_config ? gc->set_config(gc, offset, config) : -ENOTSUPP;
2618 * gpiod_direction_input - set the GPIO direction to input
2619 * @desc: GPIO to set to input
2621 * Set the direction of the passed GPIO to input, such as gpiod_get_value() can
2622 * be called safely on it.
2624 * Return 0 in case of success, else an error code.
2626 int gpiod_direction_input(struct gpio_desc *desc)
2628 struct gpio_chip *chip;
2631 VALIDATE_DESC(desc);
2632 chip = desc->gdev->chip;
2635 * It is legal to have no .get() and .direction_input() specified if
2636 * the chip is output-only, but you can't specify .direction_input()
2637 * and not support the .get() operation, that doesn't make sense.
2639 if (!chip->get && chip->direction_input) {
2641 "%s: missing get() but have direction_input()\n",
2647 * If we have a .direction_input() callback, things are simple,
2648 * just call it. Else we are some input-only chip so try to check the
2649 * direction (if .get_direction() is supported) else we silently
2650 * assume we are in input mode after this.
2652 if (chip->direction_input) {
2653 status = chip->direction_input(chip, gpio_chip_hwgpio(desc));
2654 } else if (chip->get_direction &&
2655 (chip->get_direction(chip, gpio_chip_hwgpio(desc)) != 1)) {
2657 "%s: missing direction_input() operation and line is output\n",
2662 clear_bit(FLAG_IS_OUT, &desc->flags);
2664 if (test_bit(FLAG_PULL_UP, &desc->flags))
2665 gpio_set_config(chip, gpio_chip_hwgpio(desc),
2666 PIN_CONFIG_BIAS_PULL_UP);
2667 else if (test_bit(FLAG_PULL_DOWN, &desc->flags))
2668 gpio_set_config(chip, gpio_chip_hwgpio(desc),
2669 PIN_CONFIG_BIAS_PULL_DOWN);
2671 trace_gpio_direction(desc_to_gpio(desc), 1, status);
2675 EXPORT_SYMBOL_GPL(gpiod_direction_input);
2677 static int gpiod_direction_output_raw_commit(struct gpio_desc *desc, int value)
2679 struct gpio_chip *gc = desc->gdev->chip;
2684 * It's OK not to specify .direction_output() if the gpiochip is
2685 * output-only, but if there is then not even a .set() operation it
2686 * is pretty tricky to drive the output line.
2688 if (!gc->set && !gc->direction_output) {
2690 "%s: missing set() and direction_output() operations\n",
2695 if (gc->direction_output) {
2696 ret = gc->direction_output(gc, gpio_chip_hwgpio(desc), val);
2698 /* Check that we are in output mode if we can */
2699 if (gc->get_direction &&
2700 gc->get_direction(gc, gpio_chip_hwgpio(desc))) {
2702 "%s: missing direction_output() operation\n",
2707 * If we can't actively set the direction, we are some
2708 * output-only chip, so just drive the output as desired.
2710 gc->set(gc, gpio_chip_hwgpio(desc), val);
2714 set_bit(FLAG_IS_OUT, &desc->flags);
2715 trace_gpio_value(desc_to_gpio(desc), 0, val);
2716 trace_gpio_direction(desc_to_gpio(desc), 0, ret);
2721 * gpiod_direction_output_raw - set the GPIO direction to output
2722 * @desc: GPIO to set to output
2723 * @value: initial output value of the GPIO
2725 * Set the direction of the passed GPIO to output, such as gpiod_set_value() can
2726 * be called safely on it. The initial value of the output must be specified
2727 * as raw value on the physical line without regard for the ACTIVE_LOW status.
2729 * Return 0 in case of success, else an error code.
2731 int gpiod_direction_output_raw(struct gpio_desc *desc, int value)
2733 VALIDATE_DESC(desc);
2734 return gpiod_direction_output_raw_commit(desc, value);
2736 EXPORT_SYMBOL_GPL(gpiod_direction_output_raw);
2739 * gpiod_direction_output - set the GPIO direction to output
2740 * @desc: GPIO to set to output
2741 * @value: initial output value of the GPIO
2743 * Set the direction of the passed GPIO to output, such as gpiod_set_value() can
2744 * be called safely on it. The initial value of the output must be specified
2745 * as the logical value of the GPIO, i.e. taking its ACTIVE_LOW status into
2748 * Return 0 in case of success, else an error code.
2750 int gpiod_direction_output(struct gpio_desc *desc, int value)
2752 struct gpio_chip *gc;
2755 VALIDATE_DESC(desc);
2756 if (test_bit(FLAG_ACTIVE_LOW, &desc->flags))
2761 /* GPIOs used for enabled IRQs shall not be set as output */
2762 if (test_bit(FLAG_USED_AS_IRQ, &desc->flags) &&
2763 test_bit(FLAG_IRQ_IS_ENABLED, &desc->flags)) {
2765 "%s: tried to set a GPIO tied to an IRQ as output\n",
2770 gc = desc->gdev->chip;
2771 if (test_bit(FLAG_OPEN_DRAIN, &desc->flags)) {
2772 /* First see if we can enable open drain in hardware */
2773 ret = gpio_set_config(gc, gpio_chip_hwgpio(desc),
2774 PIN_CONFIG_DRIVE_OPEN_DRAIN);
2776 goto set_output_value;
2777 /* Emulate open drain by not actively driving the line high */
2779 return gpiod_direction_input(desc);
2781 else if (test_bit(FLAG_OPEN_SOURCE, &desc->flags)) {
2782 ret = gpio_set_config(gc, gpio_chip_hwgpio(desc),
2783 PIN_CONFIG_DRIVE_OPEN_SOURCE);
2785 goto set_output_value;
2786 /* Emulate open source by not actively driving the line low */
2788 return gpiod_direction_input(desc);
2790 gpio_set_config(gc, gpio_chip_hwgpio(desc),
2791 PIN_CONFIG_DRIVE_PUSH_PULL);
2795 return gpiod_direction_output_raw_commit(desc, value);
2797 EXPORT_SYMBOL_GPL(gpiod_direction_output);
2800 * gpiod_set_debounce - sets @debounce time for a GPIO
2801 * @desc: descriptor of the GPIO for which to set debounce time
2802 * @debounce: debounce time in microseconds
2805 * 0 on success, %-ENOTSUPP if the controller doesn't support setting the
2808 int gpiod_set_debounce(struct gpio_desc *desc, unsigned debounce)
2810 struct gpio_chip *chip;
2811 unsigned long config;
2813 VALIDATE_DESC(desc);
2814 chip = desc->gdev->chip;
2815 if (!chip->set || !chip->set_config) {
2817 "%s: missing set() or set_config() operations\n",
2822 config = pinconf_to_config_packed(PIN_CONFIG_INPUT_DEBOUNCE, debounce);
2823 return chip->set_config(chip, gpio_chip_hwgpio(desc), config);
2825 EXPORT_SYMBOL_GPL(gpiod_set_debounce);
2828 * gpiod_set_transitory - Lose or retain GPIO state on suspend or reset
2829 * @desc: descriptor of the GPIO for which to configure persistence
2830 * @transitory: True to lose state on suspend or reset, false for persistence
2833 * 0 on success, otherwise a negative error code.
2835 int gpiod_set_transitory(struct gpio_desc *desc, bool transitory)
2837 struct gpio_chip *chip;
2838 unsigned long packed;
2842 VALIDATE_DESC(desc);
2844 * Handle FLAG_TRANSITORY first, enabling queries to gpiolib for
2845 * persistence state.
2848 set_bit(FLAG_TRANSITORY, &desc->flags);
2850 clear_bit(FLAG_TRANSITORY, &desc->flags);
2852 /* If the driver supports it, set the persistence state now */
2853 chip = desc->gdev->chip;
2854 if (!chip->set_config)
2857 packed = pinconf_to_config_packed(PIN_CONFIG_PERSIST_STATE,
2859 gpio = gpio_chip_hwgpio(desc);
2860 rc = chip->set_config(chip, gpio, packed);
2861 if (rc == -ENOTSUPP) {
2862 dev_dbg(&desc->gdev->dev, "Persistence not supported for GPIO %d\n",
2869 EXPORT_SYMBOL_GPL(gpiod_set_transitory);
2872 * gpiod_is_active_low - test whether a GPIO is active-low or not
2873 * @desc: the gpio descriptor to test
2875 * Returns 1 if the GPIO is active-low, 0 otherwise.
2877 int gpiod_is_active_low(const struct gpio_desc *desc)
2879 VALIDATE_DESC(desc);
2880 return test_bit(FLAG_ACTIVE_LOW, &desc->flags);
2882 EXPORT_SYMBOL_GPL(gpiod_is_active_low);
2884 /* I/O calls are only valid after configuration completed; the relevant
2885 * "is this a valid GPIO" error checks should already have been done.
2887 * "Get" operations are often inlinable as reading a pin value register,
2888 * and masking the relevant bit in that register.
2890 * When "set" operations are inlinable, they involve writing that mask to
2891 * one register to set a low value, or a different register to set it high.
2892 * Otherwise locking is needed, so there may be little value to inlining.
2894 *------------------------------------------------------------------------
2896 * IMPORTANT!!! The hot paths -- get/set value -- assume that callers
2897 * have requested the GPIO. That can include implicit requesting by
2898 * a direction setting call. Marking a gpio as requested locks its chip
2899 * in memory, guaranteeing that these table lookups need no more locking
2900 * and that gpiochip_remove() will fail.
2902 * REVISIT when debugging, consider adding some instrumentation to ensure
2903 * that the GPIO was actually requested.
2906 static int gpiod_get_raw_value_commit(const struct gpio_desc *desc)
2908 struct gpio_chip *chip;
2912 chip = desc->gdev->chip;
2913 offset = gpio_chip_hwgpio(desc);
2914 value = chip->get ? chip->get(chip, offset) : -EIO;
2915 value = value < 0 ? value : !!value;
2916 trace_gpio_value(desc_to_gpio(desc), 1, value);
2920 static int gpio_chip_get_multiple(struct gpio_chip *chip,
2921 unsigned long *mask, unsigned long *bits)
2923 if (chip->get_multiple) {
2924 return chip->get_multiple(chip, mask, bits);
2925 } else if (chip->get) {
2928 for_each_set_bit(i, mask, chip->ngpio) {
2929 value = chip->get(chip, i);
2932 __assign_bit(i, bits, value);
2939 int gpiod_get_array_value_complex(bool raw, bool can_sleep,
2940 unsigned int array_size,
2941 struct gpio_desc **desc_array,
2942 struct gpio_array *array_info,
2943 unsigned long *value_bitmap)
2948 * Validate array_info against desc_array and its size.
2949 * It should immediately follow desc_array if both
2950 * have been obtained from the same gpiod_get_array() call.
2952 if (array_info && array_info->desc == desc_array &&
2953 array_size <= array_info->size &&
2954 (void *)array_info == desc_array + array_info->size) {
2956 WARN_ON(array_info->chip->can_sleep);
2958 err = gpio_chip_get_multiple(array_info->chip,
2959 array_info->get_mask,
2964 if (!raw && !bitmap_empty(array_info->invert_mask, array_size))
2965 bitmap_xor(value_bitmap, value_bitmap,
2966 array_info->invert_mask, array_size);
2968 if (bitmap_full(array_info->get_mask, array_size))
2971 i = find_first_zero_bit(array_info->get_mask, array_size);
2976 while (i < array_size) {
2977 struct gpio_chip *chip = desc_array[i]->gdev->chip;
2978 unsigned long fastpath[2 * BITS_TO_LONGS(FASTPATH_NGPIO)];
2979 unsigned long *mask, *bits;
2982 if (likely(chip->ngpio <= FASTPATH_NGPIO)) {
2985 mask = kmalloc_array(2 * BITS_TO_LONGS(chip->ngpio),
2987 can_sleep ? GFP_KERNEL : GFP_ATOMIC);
2992 bits = mask + BITS_TO_LONGS(chip->ngpio);
2993 bitmap_zero(mask, chip->ngpio);
2996 WARN_ON(chip->can_sleep);
2998 /* collect all inputs belonging to the same chip */
3001 const struct gpio_desc *desc = desc_array[i];
3002 int hwgpio = gpio_chip_hwgpio(desc);
3004 __set_bit(hwgpio, mask);
3008 i = find_next_zero_bit(array_info->get_mask,
3010 } while ((i < array_size) &&
3011 (desc_array[i]->gdev->chip == chip));
3013 ret = gpio_chip_get_multiple(chip, mask, bits);
3015 if (mask != fastpath)
3020 for (j = first; j < i; ) {
3021 const struct gpio_desc *desc = desc_array[j];
3022 int hwgpio = gpio_chip_hwgpio(desc);
3023 int value = test_bit(hwgpio, bits);
3025 if (!raw && test_bit(FLAG_ACTIVE_LOW, &desc->flags))
3027 __assign_bit(j, value_bitmap, value);
3028 trace_gpio_value(desc_to_gpio(desc), 1, value);
3032 j = find_next_zero_bit(array_info->get_mask, i,
3036 if (mask != fastpath)
3043 * gpiod_get_raw_value() - return a gpio's raw value
3044 * @desc: gpio whose value will be returned
3046 * Return the GPIO's raw value, i.e. the value of the physical line disregarding
3047 * its ACTIVE_LOW status, or negative errno on failure.
3049 * This function can be called from contexts where we cannot sleep, and will
3050 * complain if the GPIO chip functions potentially sleep.
3052 int gpiod_get_raw_value(const struct gpio_desc *desc)
3054 VALIDATE_DESC(desc);
3055 /* Should be using gpiod_get_raw_value_cansleep() */
3056 WARN_ON(desc->gdev->chip->can_sleep);
3057 return gpiod_get_raw_value_commit(desc);
3059 EXPORT_SYMBOL_GPL(gpiod_get_raw_value);
3062 * gpiod_get_value() - return a gpio's value
3063 * @desc: gpio whose value will be returned
3065 * Return the GPIO's logical value, i.e. taking the ACTIVE_LOW status into
3066 * account, or negative errno on failure.
3068 * This function can be called from contexts where we cannot sleep, and will
3069 * complain if the GPIO chip functions potentially sleep.
3071 int gpiod_get_value(const struct gpio_desc *desc)
3075 VALIDATE_DESC(desc);
3076 /* Should be using gpiod_get_value_cansleep() */
3077 WARN_ON(desc->gdev->chip->can_sleep);
3079 value = gpiod_get_raw_value_commit(desc);
3083 if (test_bit(FLAG_ACTIVE_LOW, &desc->flags))
3088 EXPORT_SYMBOL_GPL(gpiod_get_value);
3091 * gpiod_get_raw_array_value() - read raw values from an array of GPIOs
3092 * @array_size: number of elements in the descriptor array / value bitmap
3093 * @desc_array: array of GPIO descriptors whose values will be read
3094 * @array_info: information on applicability of fast bitmap processing path
3095 * @value_bitmap: bitmap to store the read values
3097 * Read the raw values of the GPIOs, i.e. the values of the physical lines
3098 * without regard for their ACTIVE_LOW status. Return 0 in case of success,
3099 * else an error code.
3101 * This function can be called from contexts where we cannot sleep,
3102 * and it will complain if the GPIO chip functions potentially sleep.
3104 int gpiod_get_raw_array_value(unsigned int array_size,
3105 struct gpio_desc **desc_array,
3106 struct gpio_array *array_info,
3107 unsigned long *value_bitmap)
3111 return gpiod_get_array_value_complex(true, false, array_size,
3112 desc_array, array_info,
3115 EXPORT_SYMBOL_GPL(gpiod_get_raw_array_value);
3118 * gpiod_get_array_value() - read values from an array of GPIOs
3119 * @array_size: number of elements in the descriptor array / value bitmap
3120 * @desc_array: array of GPIO descriptors whose values will be read
3121 * @array_info: information on applicability of fast bitmap processing path
3122 * @value_bitmap: bitmap to store the read values
3124 * Read the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status
3125 * into account. Return 0 in case of success, else an error code.
3127 * This function can be called from contexts where we cannot sleep,
3128 * and it will complain if the GPIO chip functions potentially sleep.
3130 int gpiod_get_array_value(unsigned int array_size,
3131 struct gpio_desc **desc_array,
3132 struct gpio_array *array_info,
3133 unsigned long *value_bitmap)
3137 return gpiod_get_array_value_complex(false, false, array_size,
3138 desc_array, array_info,
3141 EXPORT_SYMBOL_GPL(gpiod_get_array_value);
3144 * gpio_set_open_drain_value_commit() - Set the open drain gpio's value.
3145 * @desc: gpio descriptor whose state need to be set.
3146 * @value: Non-zero for setting it HIGH otherwise it will set to LOW.
3148 static void gpio_set_open_drain_value_commit(struct gpio_desc *desc, bool value)
3151 struct gpio_chip *chip = desc->gdev->chip;
3152 int offset = gpio_chip_hwgpio(desc);
3155 err = chip->direction_input(chip, offset);
3157 clear_bit(FLAG_IS_OUT, &desc->flags);
3159 err = chip->direction_output(chip, offset, 0);
3161 set_bit(FLAG_IS_OUT, &desc->flags);
3163 trace_gpio_direction(desc_to_gpio(desc), value, err);
3166 "%s: Error in set_value for open drain err %d\n",
3171 * _gpio_set_open_source_value() - Set the open source gpio's value.
3172 * @desc: gpio descriptor whose state need to be set.
3173 * @value: Non-zero for setting it HIGH otherwise it will set to LOW.
3175 static void gpio_set_open_source_value_commit(struct gpio_desc *desc, bool value)
3178 struct gpio_chip *chip = desc->gdev->chip;
3179 int offset = gpio_chip_hwgpio(desc);
3182 err = chip->direction_output(chip, offset, 1);
3184 set_bit(FLAG_IS_OUT, &desc->flags);
3186 err = chip->direction_input(chip, offset);
3188 clear_bit(FLAG_IS_OUT, &desc->flags);
3190 trace_gpio_direction(desc_to_gpio(desc), !value, err);
3193 "%s: Error in set_value for open source err %d\n",
3197 static void gpiod_set_raw_value_commit(struct gpio_desc *desc, bool value)
3199 struct gpio_chip *chip;
3201 chip = desc->gdev->chip;
3202 trace_gpio_value(desc_to_gpio(desc), 0, value);
3203 chip->set(chip, gpio_chip_hwgpio(desc), value);
3207 * set multiple outputs on the same chip;
3208 * use the chip's set_multiple function if available;
3209 * otherwise set the outputs sequentially;
3210 * @mask: bit mask array; one bit per output; BITS_PER_LONG bits per word
3211 * defines which outputs are to be changed
3212 * @bits: bit value array; one bit per output; BITS_PER_LONG bits per word
3213 * defines the values the outputs specified by mask are to be set to
3215 static void gpio_chip_set_multiple(struct gpio_chip *chip,
3216 unsigned long *mask, unsigned long *bits)
3218 if (chip->set_multiple) {
3219 chip->set_multiple(chip, mask, bits);
3223 /* set outputs if the corresponding mask bit is set */
3224 for_each_set_bit(i, mask, chip->ngpio)
3225 chip->set(chip, i, test_bit(i, bits));
3229 int gpiod_set_array_value_complex(bool raw, bool can_sleep,
3230 unsigned int array_size,
3231 struct gpio_desc **desc_array,
3232 struct gpio_array *array_info,
3233 unsigned long *value_bitmap)
3238 * Validate array_info against desc_array and its size.
3239 * It should immediately follow desc_array if both
3240 * have been obtained from the same gpiod_get_array() call.
3242 if (array_info && array_info->desc == desc_array &&
3243 array_size <= array_info->size &&
3244 (void *)array_info == desc_array + array_info->size) {
3246 WARN_ON(array_info->chip->can_sleep);
3248 if (!raw && !bitmap_empty(array_info->invert_mask, array_size))
3249 bitmap_xor(value_bitmap, value_bitmap,
3250 array_info->invert_mask, array_size);
3252 gpio_chip_set_multiple(array_info->chip, array_info->set_mask,
3255 if (bitmap_full(array_info->set_mask, array_size))
3258 i = find_first_zero_bit(array_info->set_mask, array_size);
3263 while (i < array_size) {
3264 struct gpio_chip *chip = desc_array[i]->gdev->chip;
3265 unsigned long fastpath[2 * BITS_TO_LONGS(FASTPATH_NGPIO)];
3266 unsigned long *mask, *bits;
3269 if (likely(chip->ngpio <= FASTPATH_NGPIO)) {
3272 mask = kmalloc_array(2 * BITS_TO_LONGS(chip->ngpio),
3274 can_sleep ? GFP_KERNEL : GFP_ATOMIC);
3279 bits = mask + BITS_TO_LONGS(chip->ngpio);
3280 bitmap_zero(mask, chip->ngpio);
3283 WARN_ON(chip->can_sleep);
3286 struct gpio_desc *desc = desc_array[i];
3287 int hwgpio = gpio_chip_hwgpio(desc);
3288 int value = test_bit(i, value_bitmap);
3291 * Pins applicable for fast input but not for
3292 * fast output processing may have been already
3293 * inverted inside the fast path, skip them.
3295 if (!raw && !(array_info &&
3296 test_bit(i, array_info->invert_mask)) &&
3297 test_bit(FLAG_ACTIVE_LOW, &desc->flags))
3299 trace_gpio_value(desc_to_gpio(desc), 0, value);
3301 * collect all normal outputs belonging to the same chip
3302 * open drain and open source outputs are set individually
3304 if (test_bit(FLAG_OPEN_DRAIN, &desc->flags) && !raw) {
3305 gpio_set_open_drain_value_commit(desc, value);
3306 } else if (test_bit(FLAG_OPEN_SOURCE, &desc->flags) && !raw) {
3307 gpio_set_open_source_value_commit(desc, value);
3309 __set_bit(hwgpio, mask);
3311 __set_bit(hwgpio, bits);
3313 __clear_bit(hwgpio, bits);
3319 i = find_next_zero_bit(array_info->set_mask,
3321 } while ((i < array_size) &&
3322 (desc_array[i]->gdev->chip == chip));
3323 /* push collected bits to outputs */
3325 gpio_chip_set_multiple(chip, mask, bits);
3327 if (mask != fastpath)
3334 * gpiod_set_raw_value() - assign a gpio's raw value
3335 * @desc: gpio whose value will be assigned
3336 * @value: value to assign
3338 * Set the raw value of the GPIO, i.e. the value of its physical line without
3339 * regard for its ACTIVE_LOW status.
3341 * This function can be called from contexts where we cannot sleep, and will
3342 * complain if the GPIO chip functions potentially sleep.
3344 void gpiod_set_raw_value(struct gpio_desc *desc, int value)
3346 VALIDATE_DESC_VOID(desc);
3347 /* Should be using gpiod_set_raw_value_cansleep() */
3348 WARN_ON(desc->gdev->chip->can_sleep);
3349 gpiod_set_raw_value_commit(desc, value);
3351 EXPORT_SYMBOL_GPL(gpiod_set_raw_value);
3354 * gpiod_set_value_nocheck() - set a GPIO line value without checking
3355 * @desc: the descriptor to set the value on
3356 * @value: value to set
3358 * This sets the value of a GPIO line backing a descriptor, applying
3359 * different semantic quirks like active low and open drain/source
3362 static void gpiod_set_value_nocheck(struct gpio_desc *desc, int value)
3364 if (test_bit(FLAG_ACTIVE_LOW, &desc->flags))
3366 if (test_bit(FLAG_OPEN_DRAIN, &desc->flags))
3367 gpio_set_open_drain_value_commit(desc, value);
3368 else if (test_bit(FLAG_OPEN_SOURCE, &desc->flags))
3369 gpio_set_open_source_value_commit(desc, value);
3371 gpiod_set_raw_value_commit(desc, value);
3375 * gpiod_set_value() - assign a gpio's value
3376 * @desc: gpio whose value will be assigned
3377 * @value: value to assign
3379 * Set the logical value of the GPIO, i.e. taking its ACTIVE_LOW,
3380 * OPEN_DRAIN and OPEN_SOURCE flags into account.
3382 * This function can be called from contexts where we cannot sleep, and will
3383 * complain if the GPIO chip functions potentially sleep.
3385 void gpiod_set_value(struct gpio_desc *desc, int value)
3387 VALIDATE_DESC_VOID(desc);
3388 /* Should be using gpiod_set_value_cansleep() */
3389 WARN_ON(desc->gdev->chip->can_sleep);
3390 gpiod_set_value_nocheck(desc, value);
3392 EXPORT_SYMBOL_GPL(gpiod_set_value);
3395 * gpiod_set_raw_array_value() - assign values to an array of GPIOs
3396 * @array_size: number of elements in the descriptor array / value bitmap
3397 * @desc_array: array of GPIO descriptors whose values will be assigned
3398 * @array_info: information on applicability of fast bitmap processing path
3399 * @value_bitmap: bitmap of values to assign
3401 * Set the raw values of the GPIOs, i.e. the values of the physical lines
3402 * without regard for their ACTIVE_LOW status.
3404 * This function can be called from contexts where we cannot sleep, and will
3405 * complain if the GPIO chip functions potentially sleep.
3407 int gpiod_set_raw_array_value(unsigned int array_size,
3408 struct gpio_desc **desc_array,
3409 struct gpio_array *array_info,
3410 unsigned long *value_bitmap)
3414 return gpiod_set_array_value_complex(true, false, array_size,
3415 desc_array, array_info, value_bitmap);
3417 EXPORT_SYMBOL_GPL(gpiod_set_raw_array_value);
3420 * gpiod_set_array_value() - assign values to an array of GPIOs
3421 * @array_size: number of elements in the descriptor array / value bitmap
3422 * @desc_array: array of GPIO descriptors whose values will be assigned
3423 * @array_info: information on applicability of fast bitmap processing path
3424 * @value_bitmap: bitmap of values to assign
3426 * Set the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status
3429 * This function can be called from contexts where we cannot sleep, and will
3430 * complain if the GPIO chip functions potentially sleep.
3432 int gpiod_set_array_value(unsigned int array_size,
3433 struct gpio_desc **desc_array,
3434 struct gpio_array *array_info,
3435 unsigned long *value_bitmap)
3439 return gpiod_set_array_value_complex(false, false, array_size,
3440 desc_array, array_info,
3443 EXPORT_SYMBOL_GPL(gpiod_set_array_value);
3446 * gpiod_cansleep() - report whether gpio value access may sleep
3447 * @desc: gpio to check
3450 int gpiod_cansleep(const struct gpio_desc *desc)
3452 VALIDATE_DESC(desc);
3453 return desc->gdev->chip->can_sleep;
3455 EXPORT_SYMBOL_GPL(gpiod_cansleep);
3458 * gpiod_set_consumer_name() - set the consumer name for the descriptor
3459 * @desc: gpio to set the consumer name on
3460 * @name: the new consumer name
3462 int gpiod_set_consumer_name(struct gpio_desc *desc, const char *name)
3464 VALIDATE_DESC(desc);
3466 name = kstrdup_const(name, GFP_KERNEL);
3471 kfree_const(desc->label);
3472 desc_set_label(desc, name);
3476 EXPORT_SYMBOL_GPL(gpiod_set_consumer_name);
3479 * gpiod_to_irq() - return the IRQ corresponding to a GPIO
3480 * @desc: gpio whose IRQ will be returned (already requested)
3482 * Return the IRQ corresponding to the passed GPIO, or an error code in case of
3485 int gpiod_to_irq(const struct gpio_desc *desc)
3487 struct gpio_chip *chip;
3491 * Cannot VALIDATE_DESC() here as gpiod_to_irq() consumer semantics
3492 * requires this function to not return zero on an invalid descriptor
3493 * but rather a negative error number.
3495 if (!desc || IS_ERR(desc) || !desc->gdev || !desc->gdev->chip)
3498 chip = desc->gdev->chip;
3499 offset = gpio_chip_hwgpio(desc);
3501 int retirq = chip->to_irq(chip, offset);
3503 /* Zero means NO_IRQ */
3511 EXPORT_SYMBOL_GPL(gpiod_to_irq);
3514 * gpiochip_lock_as_irq() - lock a GPIO to be used as IRQ
3515 * @chip: the chip the GPIO to lock belongs to
3516 * @offset: the offset of the GPIO to lock as IRQ
3518 * This is used directly by GPIO drivers that want to lock down
3519 * a certain GPIO line to be used for IRQs.
3521 int gpiochip_lock_as_irq(struct gpio_chip *chip, unsigned int offset)
3523 struct gpio_desc *desc;
3525 desc = gpiochip_get_desc(chip, offset);
3527 return PTR_ERR(desc);
3530 * If it's fast: flush the direction setting if something changed
3533 if (!chip->can_sleep && chip->get_direction) {
3534 int dir = gpiod_get_direction(desc);
3537 chip_err(chip, "%s: cannot get GPIO direction\n",
3543 if (test_bit(FLAG_IS_OUT, &desc->flags)) {
3545 "%s: tried to flag a GPIO set as output for IRQ\n",
3550 set_bit(FLAG_USED_AS_IRQ, &desc->flags);
3551 set_bit(FLAG_IRQ_IS_ENABLED, &desc->flags);
3554 * If the consumer has not set up a label (such as when the
3555 * IRQ is referenced from .to_irq()) we set up a label here
3556 * so it is clear this is used as an interrupt.
3559 desc_set_label(desc, "interrupt");
3563 EXPORT_SYMBOL_GPL(gpiochip_lock_as_irq);
3566 * gpiochip_unlock_as_irq() - unlock a GPIO used as IRQ
3567 * @chip: the chip the GPIO to lock belongs to
3568 * @offset: the offset of the GPIO to lock as IRQ
3570 * This is used directly by GPIO drivers that want to indicate
3571 * that a certain GPIO is no longer used exclusively for IRQ.
3573 void gpiochip_unlock_as_irq(struct gpio_chip *chip, unsigned int offset)
3575 struct gpio_desc *desc;
3577 desc = gpiochip_get_desc(chip, offset);
3581 clear_bit(FLAG_USED_AS_IRQ, &desc->flags);
3582 clear_bit(FLAG_IRQ_IS_ENABLED, &desc->flags);
3584 /* If we only had this marking, erase it */
3585 if (desc->label && !strcmp(desc->label, "interrupt"))
3586 desc_set_label(desc, NULL);
3588 EXPORT_SYMBOL_GPL(gpiochip_unlock_as_irq);
3590 void gpiochip_disable_irq(struct gpio_chip *chip, unsigned int offset)
3592 struct gpio_desc *desc = gpiochip_get_desc(chip, offset);
3594 if (!IS_ERR(desc) &&
3595 !WARN_ON(!test_bit(FLAG_USED_AS_IRQ, &desc->flags)))
3596 clear_bit(FLAG_IRQ_IS_ENABLED, &desc->flags);
3598 EXPORT_SYMBOL_GPL(gpiochip_disable_irq);
3600 void gpiochip_enable_irq(struct gpio_chip *chip, unsigned int offset)
3602 struct gpio_desc *desc = gpiochip_get_desc(chip, offset);
3604 if (!IS_ERR(desc) &&
3605 !WARN_ON(!test_bit(FLAG_USED_AS_IRQ, &desc->flags))) {
3606 WARN_ON(test_bit(FLAG_IS_OUT, &desc->flags));
3607 set_bit(FLAG_IRQ_IS_ENABLED, &desc->flags);
3610 EXPORT_SYMBOL_GPL(gpiochip_enable_irq);
3612 bool gpiochip_line_is_irq(struct gpio_chip *chip, unsigned int offset)
3614 if (offset >= chip->ngpio)
3617 return test_bit(FLAG_USED_AS_IRQ, &chip->gpiodev->descs[offset].flags);
3619 EXPORT_SYMBOL_GPL(gpiochip_line_is_irq);
3621 int gpiochip_reqres_irq(struct gpio_chip *chip, unsigned int offset)
3625 if (!try_module_get(chip->gpiodev->owner))
3628 ret = gpiochip_lock_as_irq(chip, offset);
3630 chip_err(chip, "unable to lock HW IRQ %u for IRQ\n", offset);
3631 module_put(chip->gpiodev->owner);
3636 EXPORT_SYMBOL_GPL(gpiochip_reqres_irq);
3638 void gpiochip_relres_irq(struct gpio_chip *chip, unsigned int offset)
3640 gpiochip_unlock_as_irq(chip, offset);
3641 module_put(chip->gpiodev->owner);
3643 EXPORT_SYMBOL_GPL(gpiochip_relres_irq);
3645 bool gpiochip_line_is_open_drain(struct gpio_chip *chip, unsigned int offset)
3647 if (offset >= chip->ngpio)
3650 return test_bit(FLAG_OPEN_DRAIN, &chip->gpiodev->descs[offset].flags);
3652 EXPORT_SYMBOL_GPL(gpiochip_line_is_open_drain);
3654 bool gpiochip_line_is_open_source(struct gpio_chip *chip, unsigned int offset)
3656 if (offset >= chip->ngpio)
3659 return test_bit(FLAG_OPEN_SOURCE, &chip->gpiodev->descs[offset].flags);
3661 EXPORT_SYMBOL_GPL(gpiochip_line_is_open_source);
3663 bool gpiochip_line_is_persistent(struct gpio_chip *chip, unsigned int offset)
3665 if (offset >= chip->ngpio)
3668 return !test_bit(FLAG_TRANSITORY, &chip->gpiodev->descs[offset].flags);
3670 EXPORT_SYMBOL_GPL(gpiochip_line_is_persistent);
3673 * gpiod_get_raw_value_cansleep() - return a gpio's raw value
3674 * @desc: gpio whose value will be returned
3676 * Return the GPIO's raw value, i.e. the value of the physical line disregarding
3677 * its ACTIVE_LOW status, or negative errno on failure.
3679 * This function is to be called from contexts that can sleep.
3681 int gpiod_get_raw_value_cansleep(const struct gpio_desc *desc)
3683 might_sleep_if(extra_checks);
3684 VALIDATE_DESC(desc);
3685 return gpiod_get_raw_value_commit(desc);
3687 EXPORT_SYMBOL_GPL(gpiod_get_raw_value_cansleep);
3690 * gpiod_get_value_cansleep() - return a gpio's value
3691 * @desc: gpio whose value will be returned
3693 * Return the GPIO's logical value, i.e. taking the ACTIVE_LOW status into
3694 * account, or negative errno on failure.
3696 * This function is to be called from contexts that can sleep.
3698 int gpiod_get_value_cansleep(const struct gpio_desc *desc)
3702 might_sleep_if(extra_checks);
3703 VALIDATE_DESC(desc);
3704 value = gpiod_get_raw_value_commit(desc);
3708 if (test_bit(FLAG_ACTIVE_LOW, &desc->flags))
3713 EXPORT_SYMBOL_GPL(gpiod_get_value_cansleep);
3716 * gpiod_get_raw_array_value_cansleep() - read raw values from an array of GPIOs
3717 * @array_size: number of elements in the descriptor array / value bitmap
3718 * @desc_array: array of GPIO descriptors whose values will be read
3719 * @array_info: information on applicability of fast bitmap processing path
3720 * @value_bitmap: bitmap to store the read values
3722 * Read the raw values of the GPIOs, i.e. the values of the physical lines
3723 * without regard for their ACTIVE_LOW status. Return 0 in case of success,
3724 * else an error code.
3726 * This function is to be called from contexts that can sleep.
3728 int gpiod_get_raw_array_value_cansleep(unsigned int array_size,
3729 struct gpio_desc **desc_array,
3730 struct gpio_array *array_info,
3731 unsigned long *value_bitmap)
3733 might_sleep_if(extra_checks);
3736 return gpiod_get_array_value_complex(true, true, array_size,
3737 desc_array, array_info,
3740 EXPORT_SYMBOL_GPL(gpiod_get_raw_array_value_cansleep);
3743 * gpiod_get_array_value_cansleep() - read values from an array of GPIOs
3744 * @array_size: number of elements in the descriptor array / value bitmap
3745 * @desc_array: array of GPIO descriptors whose values will be read
3746 * @array_info: information on applicability of fast bitmap processing path
3747 * @value_bitmap: bitmap to store the read values
3749 * Read the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status
3750 * into account. Return 0 in case of success, else an error code.
3752 * This function is to be called from contexts that can sleep.
3754 int gpiod_get_array_value_cansleep(unsigned int array_size,
3755 struct gpio_desc **desc_array,
3756 struct gpio_array *array_info,
3757 unsigned long *value_bitmap)
3759 might_sleep_if(extra_checks);
3762 return gpiod_get_array_value_complex(false, true, array_size,
3763 desc_array, array_info,
3766 EXPORT_SYMBOL_GPL(gpiod_get_array_value_cansleep);
3769 * gpiod_set_raw_value_cansleep() - assign a gpio's raw value
3770 * @desc: gpio whose value will be assigned
3771 * @value: value to assign
3773 * Set the raw value of the GPIO, i.e. the value of its physical line without
3774 * regard for its ACTIVE_LOW status.
3776 * This function is to be called from contexts that can sleep.
3778 void gpiod_set_raw_value_cansleep(struct gpio_desc *desc, int value)
3780 might_sleep_if(extra_checks);
3781 VALIDATE_DESC_VOID(desc);
3782 gpiod_set_raw_value_commit(desc, value);
3784 EXPORT_SYMBOL_GPL(gpiod_set_raw_value_cansleep);
3787 * gpiod_set_value_cansleep() - assign a gpio's value
3788 * @desc: gpio whose value will be assigned
3789 * @value: value to assign
3791 * Set the logical value of the GPIO, i.e. taking its ACTIVE_LOW status into
3794 * This function is to be called from contexts that can sleep.
3796 void gpiod_set_value_cansleep(struct gpio_desc *desc, int value)
3798 might_sleep_if(extra_checks);
3799 VALIDATE_DESC_VOID(desc);
3800 gpiod_set_value_nocheck(desc, value);
3802 EXPORT_SYMBOL_GPL(gpiod_set_value_cansleep);
3805 * gpiod_set_raw_array_value_cansleep() - assign values to an array of GPIOs
3806 * @array_size: number of elements in the descriptor array / value bitmap
3807 * @desc_array: array of GPIO descriptors whose values will be assigned
3808 * @array_info: information on applicability of fast bitmap processing path
3809 * @value_bitmap: bitmap of values to assign
3811 * Set the raw values of the GPIOs, i.e. the values of the physical lines
3812 * without regard for their ACTIVE_LOW status.
3814 * This function is to be called from contexts that can sleep.
3816 int gpiod_set_raw_array_value_cansleep(unsigned int array_size,
3817 struct gpio_desc **desc_array,
3818 struct gpio_array *array_info,
3819 unsigned long *value_bitmap)
3821 might_sleep_if(extra_checks);
3824 return gpiod_set_array_value_complex(true, true, array_size, desc_array,
3825 array_info, value_bitmap);
3827 EXPORT_SYMBOL_GPL(gpiod_set_raw_array_value_cansleep);
3830 * gpiod_add_lookup_tables() - register GPIO device consumers
3831 * @tables: list of tables of consumers to register
3832 * @n: number of tables in the list
3834 void gpiod_add_lookup_tables(struct gpiod_lookup_table **tables, size_t n)
3838 mutex_lock(&gpio_lookup_lock);
3840 for (i = 0; i < n; i++)
3841 list_add_tail(&tables[i]->list, &gpio_lookup_list);
3843 mutex_unlock(&gpio_lookup_lock);
3847 * gpiod_set_array_value_cansleep() - assign values to an array of GPIOs
3848 * @array_size: number of elements in the descriptor array / value bitmap
3849 * @desc_array: array of GPIO descriptors whose values will be assigned
3850 * @array_info: information on applicability of fast bitmap processing path
3851 * @value_bitmap: bitmap of values to assign
3853 * Set the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status
3856 * This function is to be called from contexts that can sleep.
3858 int gpiod_set_array_value_cansleep(unsigned int array_size,
3859 struct gpio_desc **desc_array,
3860 struct gpio_array *array_info,
3861 unsigned long *value_bitmap)
3863 might_sleep_if(extra_checks);
3866 return gpiod_set_array_value_complex(false, true, array_size,
3867 desc_array, array_info,
3870 EXPORT_SYMBOL_GPL(gpiod_set_array_value_cansleep);
3873 * gpiod_add_lookup_table() - register GPIO device consumers
3874 * @table: table of consumers to register
3876 void gpiod_add_lookup_table(struct gpiod_lookup_table *table)
3878 mutex_lock(&gpio_lookup_lock);
3880 list_add_tail(&table->list, &gpio_lookup_list);
3882 mutex_unlock(&gpio_lookup_lock);
3884 EXPORT_SYMBOL_GPL(gpiod_add_lookup_table);
3887 * gpiod_remove_lookup_table() - unregister GPIO device consumers
3888 * @table: table of consumers to unregister
3890 void gpiod_remove_lookup_table(struct gpiod_lookup_table *table)
3892 mutex_lock(&gpio_lookup_lock);
3894 list_del(&table->list);
3896 mutex_unlock(&gpio_lookup_lock);
3898 EXPORT_SYMBOL_GPL(gpiod_remove_lookup_table);
3901 * gpiod_add_hogs() - register a set of GPIO hogs from machine code
3902 * @hogs: table of gpio hog entries with a zeroed sentinel at the end
3904 void gpiod_add_hogs(struct gpiod_hog *hogs)
3906 struct gpio_chip *chip;
3907 struct gpiod_hog *hog;
3909 mutex_lock(&gpio_machine_hogs_mutex);
3911 for (hog = &hogs[0]; hog->chip_label; hog++) {
3912 list_add_tail(&hog->list, &gpio_machine_hogs);
3915 * The chip may have been registered earlier, so check if it
3916 * exists and, if so, try to hog the line now.
3918 chip = find_chip_by_name(hog->chip_label);
3920 gpiochip_machine_hog(chip, hog);
3923 mutex_unlock(&gpio_machine_hogs_mutex);
3925 EXPORT_SYMBOL_GPL(gpiod_add_hogs);
3927 static struct gpiod_lookup_table *gpiod_find_lookup_table(struct device *dev)
3929 const char *dev_id = dev ? dev_name(dev) : NULL;
3930 struct gpiod_lookup_table *table;
3932 mutex_lock(&gpio_lookup_lock);
3934 list_for_each_entry(table, &gpio_lookup_list, list) {
3935 if (table->dev_id && dev_id) {
3937 * Valid strings on both ends, must be identical to have
3940 if (!strcmp(table->dev_id, dev_id))
3944 * One of the pointers is NULL, so both must be to have
3947 if (dev_id == table->dev_id)
3954 mutex_unlock(&gpio_lookup_lock);
3958 static struct gpio_desc *gpiod_find(struct device *dev, const char *con_id,
3959 unsigned int idx, unsigned long *flags)
3961 struct gpio_desc *desc = ERR_PTR(-ENOENT);
3962 struct gpiod_lookup_table *table;
3963 struct gpiod_lookup *p;
3965 table = gpiod_find_lookup_table(dev);
3969 for (p = &table->table[0]; p->chip_label; p++) {
3970 struct gpio_chip *chip;
3972 /* idx must always match exactly */
3976 /* If the lookup entry has a con_id, require exact match */
3977 if (p->con_id && (!con_id || strcmp(p->con_id, con_id)))
3980 chip = find_chip_by_name(p->chip_label);
3984 * As the lookup table indicates a chip with
3985 * p->chip_label should exist, assume it may
3986 * still appear later and let the interested
3987 * consumer be probed again or let the Deferred
3988 * Probe infrastructure handle the error.
3990 dev_warn(dev, "cannot find GPIO chip %s, deferring\n",
3992 return ERR_PTR(-EPROBE_DEFER);
3995 if (chip->ngpio <= p->chip_hwnum) {
3997 "requested GPIO %d is out of range [0..%d] for chip %s\n",
3998 idx, chip->ngpio, chip->label);
3999 return ERR_PTR(-EINVAL);
4002 desc = gpiochip_get_desc(chip, p->chip_hwnum);
4011 static int dt_gpio_count(struct device *dev, const char *con_id)
4017 for (i = 0; i < ARRAY_SIZE(gpio_suffixes); i++) {
4019 snprintf(propname, sizeof(propname), "%s-%s",
4020 con_id, gpio_suffixes[i]);
4022 snprintf(propname, sizeof(propname), "%s",
4025 ret = of_gpio_named_count(dev->of_node, propname);
4029 return ret ? ret : -ENOENT;
4032 static int platform_gpio_count(struct device *dev, const char *con_id)
4034 struct gpiod_lookup_table *table;
4035 struct gpiod_lookup *p;
4036 unsigned int count = 0;
4038 table = gpiod_find_lookup_table(dev);
4042 for (p = &table->table[0]; p->chip_label; p++) {
4043 if ((con_id && p->con_id && !strcmp(con_id, p->con_id)) ||
4044 (!con_id && !p->con_id))
4054 * gpiod_count - return the number of GPIOs associated with a device / function
4055 * or -ENOENT if no GPIO has been assigned to the requested function
4056 * @dev: GPIO consumer, can be NULL for system-global GPIOs
4057 * @con_id: function within the GPIO consumer
4059 int gpiod_count(struct device *dev, const char *con_id)
4061 int count = -ENOENT;
4063 if (IS_ENABLED(CONFIG_OF) && dev && dev->of_node)
4064 count = dt_gpio_count(dev, con_id);
4065 else if (IS_ENABLED(CONFIG_ACPI) && dev && ACPI_HANDLE(dev))
4066 count = acpi_gpio_count(dev, con_id);
4069 count = platform_gpio_count(dev, con_id);
4073 EXPORT_SYMBOL_GPL(gpiod_count);
4076 * gpiod_get - obtain a GPIO for a given GPIO function
4077 * @dev: GPIO consumer, can be NULL for system-global GPIOs
4078 * @con_id: function within the GPIO consumer
4079 * @flags: optional GPIO initialization flags
4081 * Return the GPIO descriptor corresponding to the function con_id of device
4082 * dev, -ENOENT if no GPIO has been assigned to the requested function, or
4083 * another IS_ERR() code if an error occurred while trying to acquire the GPIO.
4085 struct gpio_desc *__must_check gpiod_get(struct device *dev, const char *con_id,
4086 enum gpiod_flags flags)
4088 return gpiod_get_index(dev, con_id, 0, flags);
4090 EXPORT_SYMBOL_GPL(gpiod_get);
4093 * gpiod_get_optional - obtain an optional GPIO for a given GPIO function
4094 * @dev: GPIO consumer, can be NULL for system-global GPIOs
4095 * @con_id: function within the GPIO consumer
4096 * @flags: optional GPIO initialization flags
4098 * This is equivalent to gpiod_get(), except that when no GPIO was assigned to
4099 * the requested function it will return NULL. This is convenient for drivers
4100 * that need to handle optional GPIOs.
4102 struct gpio_desc *__must_check gpiod_get_optional(struct device *dev,
4104 enum gpiod_flags flags)
4106 return gpiod_get_index_optional(dev, con_id, 0, flags);
4108 EXPORT_SYMBOL_GPL(gpiod_get_optional);
4112 * gpiod_configure_flags - helper function to configure a given GPIO
4113 * @desc: gpio whose value will be assigned
4114 * @con_id: function within the GPIO consumer
4115 * @lflags: bitmask of gpio_lookup_flags GPIO_* values - returned from
4116 * of_find_gpio() or of_get_gpio_hog()
4117 * @dflags: gpiod_flags - optional GPIO initialization flags
4119 * Return 0 on success, -ENOENT if no GPIO has been assigned to the
4120 * requested function and/or index, or another IS_ERR() code if an error
4121 * occurred while trying to acquire the GPIO.
4123 int gpiod_configure_flags(struct gpio_desc *desc, const char *con_id,
4124 unsigned long lflags, enum gpiod_flags dflags)
4128 if (lflags & GPIO_ACTIVE_LOW)
4129 set_bit(FLAG_ACTIVE_LOW, &desc->flags);
4131 if (lflags & GPIO_OPEN_DRAIN)
4132 set_bit(FLAG_OPEN_DRAIN, &desc->flags);
4133 else if (dflags & GPIOD_FLAGS_BIT_OPEN_DRAIN) {
4135 * This enforces open drain mode from the consumer side.
4136 * This is necessary for some busses like I2C, but the lookup
4137 * should *REALLY* have specified them as open drain in the
4138 * first place, so print a little warning here.
4140 set_bit(FLAG_OPEN_DRAIN, &desc->flags);
4142 "enforced open drain please flag it properly in DT/ACPI DSDT/board file\n");
4145 if (lflags & GPIO_OPEN_SOURCE)
4146 set_bit(FLAG_OPEN_SOURCE, &desc->flags);
4148 if ((lflags & GPIO_PULL_UP) && (lflags & GPIO_PULL_DOWN)) {
4150 "both pull-up and pull-down enabled, invalid configuration\n");
4154 if (lflags & GPIO_PULL_UP)
4155 set_bit(FLAG_PULL_UP, &desc->flags);
4156 else if (lflags & GPIO_PULL_DOWN)
4157 set_bit(FLAG_PULL_DOWN, &desc->flags);
4159 status = gpiod_set_transitory(desc, (lflags & GPIO_TRANSITORY));
4163 /* No particular flag request, return here... */
4164 if (!(dflags & GPIOD_FLAGS_BIT_DIR_SET)) {
4165 pr_debug("no flags found for %s\n", con_id);
4170 if (dflags & GPIOD_FLAGS_BIT_DIR_OUT)
4171 status = gpiod_direction_output(desc,
4172 !!(dflags & GPIOD_FLAGS_BIT_DIR_VAL));
4174 status = gpiod_direction_input(desc);
4180 * gpiod_get_index - obtain a GPIO from a multi-index GPIO function
4181 * @dev: GPIO consumer, can be NULL for system-global GPIOs
4182 * @con_id: function within the GPIO consumer
4183 * @idx: index of the GPIO to obtain in the consumer
4184 * @flags: optional GPIO initialization flags
4186 * This variant of gpiod_get() allows to access GPIOs other than the first
4187 * defined one for functions that define several GPIOs.
4189 * Return a valid GPIO descriptor, -ENOENT if no GPIO has been assigned to the
4190 * requested function and/or index, or another IS_ERR() code if an error
4191 * occurred while trying to acquire the GPIO.
4193 struct gpio_desc *__must_check gpiod_get_index(struct device *dev,
4196 enum gpiod_flags flags)
4198 unsigned long lookupflags = GPIO_LOOKUP_FLAGS_DEFAULT;
4199 struct gpio_desc *desc = NULL;
4201 /* Maybe we have a device name, maybe not */
4202 const char *devname = dev ? dev_name(dev) : "?";
4204 dev_dbg(dev, "GPIO lookup for consumer %s\n", con_id);
4207 /* Using device tree? */
4208 if (IS_ENABLED(CONFIG_OF) && dev->of_node) {
4209 dev_dbg(dev, "using device tree for GPIO lookup\n");
4210 desc = of_find_gpio(dev, con_id, idx, &lookupflags);
4211 } else if (ACPI_COMPANION(dev)) {
4212 dev_dbg(dev, "using ACPI for GPIO lookup\n");
4213 desc = acpi_find_gpio(dev, con_id, idx, &flags, &lookupflags);
4218 * Either we are not using DT or ACPI, or their lookup did not return
4219 * a result. In that case, use platform lookup as a fallback.
4221 if (!desc || desc == ERR_PTR(-ENOENT)) {
4222 dev_dbg(dev, "using lookup tables for GPIO lookup\n");
4223 desc = gpiod_find(dev, con_id, idx, &lookupflags);
4227 dev_dbg(dev, "No GPIO consumer %s found\n", con_id);
4232 * If a connection label was passed use that, else attempt to use
4233 * the device name as label
4235 status = gpiod_request(desc, con_id ? con_id : devname);
4237 if (status == -EBUSY && flags & GPIOD_FLAGS_BIT_NONEXCLUSIVE) {
4239 * This happens when there are several consumers for
4240 * the same GPIO line: we just return here without
4241 * further initialization. It is a bit if a hack.
4242 * This is necessary to support fixed regulators.
4244 * FIXME: Make this more sane and safe.
4246 dev_info(dev, "nonexclusive access to GPIO for %s\n",
4247 con_id ? con_id : devname);
4250 return ERR_PTR(status);
4254 status = gpiod_configure_flags(desc, con_id, lookupflags, flags);
4256 dev_dbg(dev, "setup of GPIO %s failed\n", con_id);
4258 return ERR_PTR(status);
4263 EXPORT_SYMBOL_GPL(gpiod_get_index);
4266 * gpiod_get_from_of_node() - obtain a GPIO from an OF node
4267 * @node: handle of the OF node
4268 * @propname: name of the DT property representing the GPIO
4269 * @index: index of the GPIO to obtain for the consumer
4270 * @dflags: GPIO initialization flags
4271 * @label: label to attach to the requested GPIO
4274 * On successful request the GPIO pin is configured in accordance with
4277 * In case of error an ERR_PTR() is returned.
4279 struct gpio_desc *gpiod_get_from_of_node(struct device_node *node,
4280 const char *propname, int index,
4281 enum gpiod_flags dflags,
4284 unsigned long lflags = GPIO_LOOKUP_FLAGS_DEFAULT;
4285 struct gpio_desc *desc;
4286 enum of_gpio_flags flags;
4287 bool active_low = false;
4288 bool single_ended = false;
4289 bool open_drain = false;
4290 bool transitory = false;
4293 desc = of_get_named_gpiod_flags(node, propname,
4296 if (!desc || IS_ERR(desc)) {
4300 active_low = flags & OF_GPIO_ACTIVE_LOW;
4301 single_ended = flags & OF_GPIO_SINGLE_ENDED;
4302 open_drain = flags & OF_GPIO_OPEN_DRAIN;
4303 transitory = flags & OF_GPIO_TRANSITORY;
4305 ret = gpiod_request(desc, label);
4306 if (ret == -EBUSY && (flags & GPIOD_FLAGS_BIT_NONEXCLUSIVE))
4309 return ERR_PTR(ret);
4312 lflags |= GPIO_ACTIVE_LOW;
4316 lflags |= GPIO_OPEN_DRAIN;
4318 lflags |= GPIO_OPEN_SOURCE;
4322 lflags |= GPIO_TRANSITORY;
4324 ret = gpiod_configure_flags(desc, propname, lflags, dflags);
4327 return ERR_PTR(ret);
4332 EXPORT_SYMBOL(gpiod_get_from_of_node);
4335 * fwnode_get_named_gpiod - obtain a GPIO from firmware node
4336 * @fwnode: handle of the firmware node
4337 * @propname: name of the firmware property representing the GPIO
4338 * @index: index of the GPIO to obtain for the consumer
4339 * @dflags: GPIO initialization flags
4340 * @label: label to attach to the requested GPIO
4342 * This function can be used for drivers that get their configuration
4343 * from opaque firmware.
4345 * The function properly finds the corresponding GPIO using whatever is the
4346 * underlying firmware interface and then makes sure that the GPIO
4347 * descriptor is requested before it is returned to the caller.
4350 * On successful request the GPIO pin is configured in accordance with
4353 * In case of error an ERR_PTR() is returned.
4355 struct gpio_desc *fwnode_get_named_gpiod(struct fwnode_handle *fwnode,
4356 const char *propname, int index,
4357 enum gpiod_flags dflags,
4360 unsigned long lflags = GPIO_LOOKUP_FLAGS_DEFAULT;
4361 struct gpio_desc *desc = ERR_PTR(-ENODEV);
4365 return ERR_PTR(-EINVAL);
4367 if (is_of_node(fwnode)) {
4368 desc = gpiod_get_from_of_node(to_of_node(fwnode),
4373 } else if (is_acpi_node(fwnode)) {
4374 struct acpi_gpio_info info;
4376 desc = acpi_node_get_gpiod(fwnode, propname, index, &info);
4380 acpi_gpio_update_gpiod_flags(&dflags, &info);
4381 acpi_gpio_update_gpiod_lookup_flags(&lflags, &info);
4384 /* Currently only ACPI takes this path */
4385 ret = gpiod_request(desc, label);
4387 return ERR_PTR(ret);
4389 ret = gpiod_configure_flags(desc, propname, lflags, dflags);
4392 return ERR_PTR(ret);
4397 EXPORT_SYMBOL_GPL(fwnode_get_named_gpiod);
4400 * gpiod_get_index_optional - obtain an optional GPIO from a multi-index GPIO
4402 * @dev: GPIO consumer, can be NULL for system-global GPIOs
4403 * @con_id: function within the GPIO consumer
4404 * @index: index of the GPIO to obtain in the consumer
4405 * @flags: optional GPIO initialization flags
4407 * This is equivalent to gpiod_get_index(), except that when no GPIO with the
4408 * specified index was assigned to the requested function it will return NULL.
4409 * This is convenient for drivers that need to handle optional GPIOs.
4411 struct gpio_desc *__must_check gpiod_get_index_optional(struct device *dev,
4414 enum gpiod_flags flags)
4416 struct gpio_desc *desc;
4418 desc = gpiod_get_index(dev, con_id, index, flags);
4420 if (PTR_ERR(desc) == -ENOENT)
4426 EXPORT_SYMBOL_GPL(gpiod_get_index_optional);
4429 * gpiod_hog - Hog the specified GPIO desc given the provided flags
4430 * @desc: gpio whose value will be assigned
4431 * @name: gpio line name
4432 * @lflags: bitmask of gpio_lookup_flags GPIO_* values - returned from
4433 * of_find_gpio() or of_get_gpio_hog()
4434 * @dflags: gpiod_flags - optional GPIO initialization flags
4436 int gpiod_hog(struct gpio_desc *desc, const char *name,
4437 unsigned long lflags, enum gpiod_flags dflags)
4439 struct gpio_chip *chip;
4440 struct gpio_desc *local_desc;
4444 chip = gpiod_to_chip(desc);
4445 hwnum = gpio_chip_hwgpio(desc);
4447 local_desc = gpiochip_request_own_desc(chip, hwnum, name,
4449 if (IS_ERR(local_desc)) {
4450 status = PTR_ERR(local_desc);
4451 pr_err("requesting hog GPIO %s (chip %s, offset %d) failed, %d\n",
4452 name, chip->label, hwnum, status);
4456 /* Mark GPIO as hogged so it can be identified and removed later */
4457 set_bit(FLAG_IS_HOGGED, &desc->flags);
4459 pr_info("GPIO line %d (%s) hogged as %s%s\n",
4460 desc_to_gpio(desc), name,
4461 (dflags&GPIOD_FLAGS_BIT_DIR_OUT) ? "output" : "input",
4462 (dflags&GPIOD_FLAGS_BIT_DIR_OUT) ?
4463 (dflags&GPIOD_FLAGS_BIT_DIR_VAL) ? "/high" : "/low":"");
4469 * gpiochip_free_hogs - Scan gpio-controller chip and release GPIO hog
4470 * @chip: gpio chip to act on
4472 static void gpiochip_free_hogs(struct gpio_chip *chip)
4476 for (id = 0; id < chip->ngpio; id++) {
4477 if (test_bit(FLAG_IS_HOGGED, &chip->gpiodev->descs[id].flags))
4478 gpiochip_free_own_desc(&chip->gpiodev->descs[id]);
4483 * gpiod_get_array - obtain multiple GPIOs from a multi-index GPIO function
4484 * @dev: GPIO consumer, can be NULL for system-global GPIOs
4485 * @con_id: function within the GPIO consumer
4486 * @flags: optional GPIO initialization flags
4488 * This function acquires all the GPIOs defined under a given function.
4490 * Return a struct gpio_descs containing an array of descriptors, -ENOENT if
4491 * no GPIO has been assigned to the requested function, or another IS_ERR()
4492 * code if an error occurred while trying to acquire the GPIOs.
4494 struct gpio_descs *__must_check gpiod_get_array(struct device *dev,
4496 enum gpiod_flags flags)
4498 struct gpio_desc *desc;
4499 struct gpio_descs *descs;
4500 struct gpio_array *array_info = NULL;
4501 struct gpio_chip *chip;
4502 int count, bitmap_size;
4504 count = gpiod_count(dev, con_id);
4506 return ERR_PTR(count);
4508 descs = kzalloc(struct_size(descs, desc, count), GFP_KERNEL);
4510 return ERR_PTR(-ENOMEM);
4512 for (descs->ndescs = 0; descs->ndescs < count; ) {
4513 desc = gpiod_get_index(dev, con_id, descs->ndescs, flags);
4515 gpiod_put_array(descs);
4516 return ERR_CAST(desc);
4519 descs->desc[descs->ndescs] = desc;
4521 chip = gpiod_to_chip(desc);
4523 * If pin hardware number of array member 0 is also 0, select
4524 * its chip as a candidate for fast bitmap processing path.
4526 if (descs->ndescs == 0 && gpio_chip_hwgpio(desc) == 0) {
4527 struct gpio_descs *array;
4529 bitmap_size = BITS_TO_LONGS(chip->ngpio > count ?
4530 chip->ngpio : count);
4532 array = kzalloc(struct_size(descs, desc, count) +
4533 struct_size(array_info, invert_mask,
4534 3 * bitmap_size), GFP_KERNEL);
4536 gpiod_put_array(descs);
4537 return ERR_PTR(-ENOMEM);
4540 memcpy(array, descs,
4541 struct_size(descs, desc, descs->ndescs + 1));
4545 array_info = (void *)(descs->desc + count);
4546 array_info->get_mask = array_info->invert_mask +
4548 array_info->set_mask = array_info->get_mask +
4551 array_info->desc = descs->desc;
4552 array_info->size = count;
4553 array_info->chip = chip;
4554 bitmap_set(array_info->get_mask, descs->ndescs,
4555 count - descs->ndescs);
4556 bitmap_set(array_info->set_mask, descs->ndescs,
4557 count - descs->ndescs);
4558 descs->info = array_info;
4560 /* Unmark array members which don't belong to the 'fast' chip */
4561 if (array_info && array_info->chip != chip) {
4562 __clear_bit(descs->ndescs, array_info->get_mask);
4563 __clear_bit(descs->ndescs, array_info->set_mask);
4566 * Detect array members which belong to the 'fast' chip
4567 * but their pins are not in hardware order.
4569 else if (array_info &&
4570 gpio_chip_hwgpio(desc) != descs->ndescs) {
4572 * Don't use fast path if all array members processed so
4573 * far belong to the same chip as this one but its pin
4574 * hardware number is different from its array index.
4576 if (bitmap_full(array_info->get_mask, descs->ndescs)) {
4579 __clear_bit(descs->ndescs,
4580 array_info->get_mask);
4581 __clear_bit(descs->ndescs,
4582 array_info->set_mask);
4584 } else if (array_info) {
4585 /* Exclude open drain or open source from fast output */
4586 if (gpiochip_line_is_open_drain(chip, descs->ndescs) ||
4587 gpiochip_line_is_open_source(chip, descs->ndescs))
4588 __clear_bit(descs->ndescs,
4589 array_info->set_mask);
4590 /* Identify 'fast' pins which require invertion */
4591 if (gpiod_is_active_low(desc))
4592 __set_bit(descs->ndescs,
4593 array_info->invert_mask);
4600 "GPIO array info: chip=%s, size=%d, get_mask=%lx, set_mask=%lx, invert_mask=%lx\n",
4601 array_info->chip->label, array_info->size,
4602 *array_info->get_mask, *array_info->set_mask,
4603 *array_info->invert_mask);
4606 EXPORT_SYMBOL_GPL(gpiod_get_array);
4609 * gpiod_get_array_optional - obtain multiple GPIOs from a multi-index GPIO
4611 * @dev: GPIO consumer, can be NULL for system-global GPIOs
4612 * @con_id: function within the GPIO consumer
4613 * @flags: optional GPIO initialization flags
4615 * This is equivalent to gpiod_get_array(), except that when no GPIO was
4616 * assigned to the requested function it will return NULL.
4618 struct gpio_descs *__must_check gpiod_get_array_optional(struct device *dev,
4620 enum gpiod_flags flags)
4622 struct gpio_descs *descs;
4624 descs = gpiod_get_array(dev, con_id, flags);
4625 if (IS_ERR(descs) && (PTR_ERR(descs) == -ENOENT))
4630 EXPORT_SYMBOL_GPL(gpiod_get_array_optional);
4633 * gpiod_put - dispose of a GPIO descriptor
4634 * @desc: GPIO descriptor to dispose of
4636 * No descriptor can be used after gpiod_put() has been called on it.
4638 void gpiod_put(struct gpio_desc *desc)
4643 EXPORT_SYMBOL_GPL(gpiod_put);
4646 * gpiod_put_array - dispose of multiple GPIO descriptors
4647 * @descs: struct gpio_descs containing an array of descriptors
4649 void gpiod_put_array(struct gpio_descs *descs)
4653 for (i = 0; i < descs->ndescs; i++)
4654 gpiod_put(descs->desc[i]);
4658 EXPORT_SYMBOL_GPL(gpiod_put_array);
4660 static int __init gpiolib_dev_init(void)
4664 /* Register GPIO sysfs bus */
4665 ret = bus_register(&gpio_bus_type);
4667 pr_err("gpiolib: could not register GPIO bus type\n");
4671 ret = alloc_chrdev_region(&gpio_devt, 0, GPIO_DEV_MAX, "gpiochip");
4673 pr_err("gpiolib: failed to allocate char dev region\n");
4674 bus_unregister(&gpio_bus_type);
4676 gpiolib_initialized = true;
4677 gpiochip_setup_devs();
4681 core_initcall(gpiolib_dev_init);
4683 #ifdef CONFIG_DEBUG_FS
4685 static void gpiolib_dbg_show(struct seq_file *s, struct gpio_device *gdev)
4688 struct gpio_chip *chip = gdev->chip;
4689 unsigned gpio = gdev->base;
4690 struct gpio_desc *gdesc = &gdev->descs[0];
4695 for (i = 0; i < gdev->ngpio; i++, gpio++, gdesc++) {
4696 if (!test_bit(FLAG_REQUESTED, &gdesc->flags)) {
4698 seq_printf(s, " gpio-%-3d (%-20.20s)\n",
4704 gpiod_get_direction(gdesc);
4705 is_out = test_bit(FLAG_IS_OUT, &gdesc->flags);
4706 is_irq = test_bit(FLAG_USED_AS_IRQ, &gdesc->flags);
4707 active_low = test_bit(FLAG_ACTIVE_LOW, &gdesc->flags);
4708 seq_printf(s, " gpio-%-3d (%-20.20s|%-20.20s) %s %s %s%s",
4709 gpio, gdesc->name ? gdesc->name : "", gdesc->label,
4710 is_out ? "out" : "in ",
4711 chip->get ? (chip->get(chip, i) ? "hi" : "lo") : "? ",
4712 is_irq ? "IRQ " : "",
4713 active_low ? "ACTIVE LOW" : "");
4714 seq_printf(s, "\n");
4718 static void *gpiolib_seq_start(struct seq_file *s, loff_t *pos)
4720 unsigned long flags;
4721 struct gpio_device *gdev = NULL;
4722 loff_t index = *pos;
4726 spin_lock_irqsave(&gpio_lock, flags);
4727 list_for_each_entry(gdev, &gpio_devices, list)
4729 spin_unlock_irqrestore(&gpio_lock, flags);
4732 spin_unlock_irqrestore(&gpio_lock, flags);
4737 static void *gpiolib_seq_next(struct seq_file *s, void *v, loff_t *pos)
4739 unsigned long flags;
4740 struct gpio_device *gdev = v;
4743 spin_lock_irqsave(&gpio_lock, flags);
4744 if (list_is_last(&gdev->list, &gpio_devices))
4747 ret = list_entry(gdev->list.next, struct gpio_device, list);
4748 spin_unlock_irqrestore(&gpio_lock, flags);
4756 static void gpiolib_seq_stop(struct seq_file *s, void *v)
4760 static int gpiolib_seq_show(struct seq_file *s, void *v)
4762 struct gpio_device *gdev = v;
4763 struct gpio_chip *chip = gdev->chip;
4764 struct device *parent;
4767 seq_printf(s, "%s%s: (dangling chip)", (char *)s->private,
4768 dev_name(&gdev->dev));
4772 seq_printf(s, "%s%s: GPIOs %d-%d", (char *)s->private,
4773 dev_name(&gdev->dev),
4774 gdev->base, gdev->base + gdev->ngpio - 1);
4775 parent = chip->parent;
4777 seq_printf(s, ", parent: %s/%s",
4778 parent->bus ? parent->bus->name : "no-bus",
4781 seq_printf(s, ", %s", chip->label);
4782 if (chip->can_sleep)
4783 seq_printf(s, ", can sleep");
4784 seq_printf(s, ":\n");
4787 chip->dbg_show(s, chip);
4789 gpiolib_dbg_show(s, gdev);
4794 static const struct seq_operations gpiolib_seq_ops = {
4795 .start = gpiolib_seq_start,
4796 .next = gpiolib_seq_next,
4797 .stop = gpiolib_seq_stop,
4798 .show = gpiolib_seq_show,
4801 static int gpiolib_open(struct inode *inode, struct file *file)
4803 return seq_open(file, &gpiolib_seq_ops);
4806 static const struct file_operations gpiolib_operations = {
4807 .owner = THIS_MODULE,
4808 .open = gpiolib_open,
4810 .llseek = seq_lseek,
4811 .release = seq_release,
4814 static int __init gpiolib_debugfs_init(void)
4816 /* /sys/kernel/debug/gpio */
4817 debugfs_create_file("gpio", S_IFREG | S_IRUGO, NULL, NULL,
4818 &gpiolib_operations);
4821 subsys_initcall(gpiolib_debugfs_init);
4823 #endif /* DEBUG_FS */