1 #include <linux/bitmap.h>
2 #include <linux/kernel.h>
3 #include <linux/module.h>
4 #include <linux/interrupt.h>
6 #include <linux/spinlock.h>
7 #include <linux/list.h>
8 #include <linux/device.h>
10 #include <linux/debugfs.h>
11 #include <linux/seq_file.h>
12 #include <linux/gpio.h>
13 #include <linux/of_gpio.h>
14 #include <linux/idr.h>
15 #include <linux/slab.h>
16 #include <linux/acpi.h>
17 #include <linux/gpio/driver.h>
18 #include <linux/gpio/machine.h>
19 #include <linux/pinctrl/consumer.h>
20 #include <linux/cdev.h>
22 #include <linux/uaccess.h>
23 #include <linux/compat.h>
24 #include <linux/anon_inodes.h>
25 #include <linux/file.h>
26 #include <linux/kfifo.h>
27 #include <linux/poll.h>
28 #include <linux/timekeeping.h>
29 #include <uapi/linux/gpio.h>
33 #define CREATE_TRACE_POINTS
34 #include <trace/events/gpio.h>
36 /* Implementation infrastructure for GPIO interfaces.
38 * The GPIO programming interface allows for inlining speed-critical
39 * get/set operations for common cases, so that access to SOC-integrated
40 * GPIOs can sometimes cost only an instruction or two per bit.
44 /* When debugging, extend minimal trust to callers and platform code.
45 * Also emit diagnostic messages that may help initial bringup, when
46 * board setup or driver bugs are most common.
48 * Otherwise, minimize overhead in what may be bitbanging codepaths.
51 #define extra_checks 1
53 #define extra_checks 0
56 /* Device and char device-related information */
57 static DEFINE_IDA(gpio_ida);
58 static dev_t gpio_devt;
59 #define GPIO_DEV_MAX 256 /* 256 GPIO chip devices supported */
60 static struct bus_type gpio_bus_type = {
65 * Number of GPIOs to use for the fast path in set array
67 #define FASTPATH_NGPIO CONFIG_GPIOLIB_FASTPATH_LIMIT
69 /* gpio_lock prevents conflicts during gpio_desc[] table updates.
70 * While any GPIO is requested, its gpio_chip is not removable;
71 * each GPIO's "requested" flag serves as a lock and refcount.
73 DEFINE_SPINLOCK(gpio_lock);
75 static DEFINE_MUTEX(gpio_lookup_lock);
76 static LIST_HEAD(gpio_lookup_list);
77 LIST_HEAD(gpio_devices);
79 static DEFINE_MUTEX(gpio_machine_hogs_mutex);
80 static LIST_HEAD(gpio_machine_hogs);
82 static void gpiochip_free_hogs(struct gpio_chip *chip);
83 static int gpiochip_add_irqchip(struct gpio_chip *gpiochip,
84 struct lock_class_key *lock_key,
85 struct lock_class_key *request_key);
86 static void gpiochip_irqchip_remove(struct gpio_chip *gpiochip);
87 static int gpiochip_irqchip_init_valid_mask(struct gpio_chip *gpiochip);
88 static void gpiochip_irqchip_free_valid_mask(struct gpio_chip *gpiochip);
90 static bool gpiolib_initialized;
92 static inline void desc_set_label(struct gpio_desc *d, const char *label)
98 * gpio_to_desc - Convert a GPIO number to its descriptor
99 * @gpio: global GPIO number
102 * The GPIO descriptor associated with the given GPIO, or %NULL if no GPIO
103 * with the given number exists in the system.
105 struct gpio_desc *gpio_to_desc(unsigned gpio)
107 struct gpio_device *gdev;
110 spin_lock_irqsave(&gpio_lock, flags);
112 list_for_each_entry(gdev, &gpio_devices, list) {
113 if (gdev->base <= gpio &&
114 gdev->base + gdev->ngpio > gpio) {
115 spin_unlock_irqrestore(&gpio_lock, flags);
116 return &gdev->descs[gpio - gdev->base];
120 spin_unlock_irqrestore(&gpio_lock, flags);
122 if (!gpio_is_valid(gpio))
123 WARN(1, "invalid GPIO %d\n", gpio);
127 EXPORT_SYMBOL_GPL(gpio_to_desc);
130 * gpiochip_get_desc - get the GPIO descriptor corresponding to the given
131 * hardware number for this chip
133 * @hwnum: hardware number of the GPIO for this chip
136 * A pointer to the GPIO descriptor or %ERR_PTR(-EINVAL) if no GPIO exists
137 * in the given chip for the specified hardware number.
139 struct gpio_desc *gpiochip_get_desc(struct gpio_chip *chip,
142 struct gpio_device *gdev = chip->gpiodev;
144 if (hwnum >= gdev->ngpio)
145 return ERR_PTR(-EINVAL);
147 return &gdev->descs[hwnum];
151 * desc_to_gpio - convert a GPIO descriptor to the integer namespace
152 * @desc: GPIO descriptor
154 * This should disappear in the future but is needed since we still
155 * use GPIO numbers for error messages and sysfs nodes.
158 * The global GPIO number for the GPIO specified by its descriptor.
160 int desc_to_gpio(const struct gpio_desc *desc)
162 return desc->gdev->base + (desc - &desc->gdev->descs[0]);
164 EXPORT_SYMBOL_GPL(desc_to_gpio);
168 * gpiod_to_chip - Return the GPIO chip to which a GPIO descriptor belongs
169 * @desc: descriptor to return the chip of
171 struct gpio_chip *gpiod_to_chip(const struct gpio_desc *desc)
173 if (!desc || !desc->gdev)
175 return desc->gdev->chip;
177 EXPORT_SYMBOL_GPL(gpiod_to_chip);
179 /* dynamic allocation of GPIOs, e.g. on a hotplugged device */
180 static int gpiochip_find_base(int ngpio)
182 struct gpio_device *gdev;
183 int base = ARCH_NR_GPIOS - ngpio;
185 list_for_each_entry_reverse(gdev, &gpio_devices, list) {
186 /* found a free space? */
187 if (gdev->base + gdev->ngpio <= base)
190 /* nope, check the space right before the chip */
191 base = gdev->base - ngpio;
194 if (gpio_is_valid(base)) {
195 pr_debug("%s: found new base at %d\n", __func__, base);
198 pr_err("%s: cannot find free range\n", __func__);
204 * gpiod_get_direction - return the current direction of a GPIO
205 * @desc: GPIO to get the direction of
207 * Returns 0 for output, 1 for input, or an error code in case of error.
209 * This function may sleep if gpiod_cansleep() is true.
211 int gpiod_get_direction(struct gpio_desc *desc)
213 struct gpio_chip *chip;
215 int status = -EINVAL;
217 chip = gpiod_to_chip(desc);
218 offset = gpio_chip_hwgpio(desc);
220 if (!chip->get_direction)
223 status = chip->get_direction(chip, offset);
225 /* GPIOF_DIR_IN, or other positive */
227 clear_bit(FLAG_IS_OUT, &desc->flags);
231 set_bit(FLAG_IS_OUT, &desc->flags);
235 EXPORT_SYMBOL_GPL(gpiod_get_direction);
238 * Add a new chip to the global chips list, keeping the list of chips sorted
239 * by range(means [base, base + ngpio - 1]) order.
241 * Return -EBUSY if the new chip overlaps with some other chip's integer
244 static int gpiodev_add_to_list(struct gpio_device *gdev)
246 struct gpio_device *prev, *next;
248 if (list_empty(&gpio_devices)) {
249 /* initial entry in list */
250 list_add_tail(&gdev->list, &gpio_devices);
254 next = list_entry(gpio_devices.next, struct gpio_device, list);
255 if (gdev->base + gdev->ngpio <= next->base) {
256 /* add before first entry */
257 list_add(&gdev->list, &gpio_devices);
261 prev = list_entry(gpio_devices.prev, struct gpio_device, list);
262 if (prev->base + prev->ngpio <= gdev->base) {
263 /* add behind last entry */
264 list_add_tail(&gdev->list, &gpio_devices);
268 list_for_each_entry_safe(prev, next, &gpio_devices, list) {
269 /* at the end of the list */
270 if (&next->list == &gpio_devices)
273 /* add between prev and next */
274 if (prev->base + prev->ngpio <= gdev->base
275 && gdev->base + gdev->ngpio <= next->base) {
276 list_add(&gdev->list, &prev->list);
281 dev_err(&gdev->dev, "GPIO integer space overlap, cannot add chip\n");
286 * Convert a GPIO name to its descriptor
288 static struct gpio_desc *gpio_name_to_desc(const char * const name)
290 struct gpio_device *gdev;
293 spin_lock_irqsave(&gpio_lock, flags);
295 list_for_each_entry(gdev, &gpio_devices, list) {
298 for (i = 0; i != gdev->ngpio; ++i) {
299 struct gpio_desc *desc = &gdev->descs[i];
301 if (!desc->name || !name)
304 if (!strcmp(desc->name, name)) {
305 spin_unlock_irqrestore(&gpio_lock, flags);
311 spin_unlock_irqrestore(&gpio_lock, flags);
317 * Takes the names from gc->names and checks if they are all unique. If they
318 * are, they are assigned to their gpio descriptors.
320 * Warning if one of the names is already used for a different GPIO.
322 static int gpiochip_set_desc_names(struct gpio_chip *gc)
324 struct gpio_device *gdev = gc->gpiodev;
330 /* First check all names if they are unique */
331 for (i = 0; i != gc->ngpio; ++i) {
332 struct gpio_desc *gpio;
334 gpio = gpio_name_to_desc(gc->names[i]);
337 "Detected name collision for GPIO name '%s'\n",
341 /* Then add all names to the GPIO descriptors */
342 for (i = 0; i != gc->ngpio; ++i)
343 gdev->descs[i].name = gc->names[i];
348 static unsigned long *gpiochip_allocate_mask(struct gpio_chip *chip)
352 p = kmalloc_array(BITS_TO_LONGS(chip->ngpio), sizeof(*p), GFP_KERNEL);
356 /* Assume by default all GPIOs are valid */
357 bitmap_fill(p, chip->ngpio);
362 static int gpiochip_init_valid_mask(struct gpio_chip *gpiochip)
364 #ifdef CONFIG_OF_GPIO
366 struct device_node *np = gpiochip->of_node;
368 size = of_property_count_u32_elems(np, "gpio-reserved-ranges");
369 if (size > 0 && size % 2 == 0)
370 gpiochip->need_valid_mask = true;
373 if (!gpiochip->need_valid_mask)
376 gpiochip->valid_mask = gpiochip_allocate_mask(gpiochip);
377 if (!gpiochip->valid_mask)
383 static void gpiochip_free_valid_mask(struct gpio_chip *gpiochip)
385 kfree(gpiochip->valid_mask);
386 gpiochip->valid_mask = NULL;
389 bool gpiochip_line_is_valid(const struct gpio_chip *gpiochip,
392 /* No mask means all valid */
393 if (likely(!gpiochip->valid_mask))
395 return test_bit(offset, gpiochip->valid_mask);
397 EXPORT_SYMBOL_GPL(gpiochip_line_is_valid);
400 * GPIO line handle management
404 * struct linehandle_state - contains the state of a userspace handle
405 * @gdev: the GPIO device the handle pertains to
406 * @label: consumer label used to tag descriptors
407 * @descs: the GPIO descriptors held by this handle
408 * @numdescs: the number of descriptors held in the descs array
410 struct linehandle_state {
411 struct gpio_device *gdev;
413 struct gpio_desc *descs[GPIOHANDLES_MAX];
417 #define GPIOHANDLE_REQUEST_VALID_FLAGS \
418 (GPIOHANDLE_REQUEST_INPUT | \
419 GPIOHANDLE_REQUEST_OUTPUT | \
420 GPIOHANDLE_REQUEST_ACTIVE_LOW | \
421 GPIOHANDLE_REQUEST_OPEN_DRAIN | \
422 GPIOHANDLE_REQUEST_OPEN_SOURCE)
424 static long linehandle_ioctl(struct file *filep, unsigned int cmd,
427 struct linehandle_state *lh = filep->private_data;
428 void __user *ip = (void __user *)arg;
429 struct gpiohandle_data ghd;
430 int vals[GPIOHANDLES_MAX];
433 if (cmd == GPIOHANDLE_GET_LINE_VALUES_IOCTL) {
434 /* TODO: check if descriptors are really input */
435 int ret = gpiod_get_array_value_complex(false,
443 memset(&ghd, 0, sizeof(ghd));
444 for (i = 0; i < lh->numdescs; i++)
445 ghd.values[i] = vals[i];
447 if (copy_to_user(ip, &ghd, sizeof(ghd)))
451 } else if (cmd == GPIOHANDLE_SET_LINE_VALUES_IOCTL) {
452 /* TODO: check if descriptors are really output */
453 if (copy_from_user(&ghd, ip, sizeof(ghd)))
456 /* Clamp all values to [0,1] */
457 for (i = 0; i < lh->numdescs; i++)
458 vals[i] = !!ghd.values[i];
460 /* Reuse the array setting function */
461 return gpiod_set_array_value_complex(false,
471 static long linehandle_ioctl_compat(struct file *filep, unsigned int cmd,
474 return linehandle_ioctl(filep, cmd, (unsigned long)compat_ptr(arg));
478 static int linehandle_release(struct inode *inode, struct file *filep)
480 struct linehandle_state *lh = filep->private_data;
481 struct gpio_device *gdev = lh->gdev;
484 for (i = 0; i < lh->numdescs; i++)
485 gpiod_free(lh->descs[i]);
488 put_device(&gdev->dev);
492 static const struct file_operations linehandle_fileops = {
493 .release = linehandle_release,
494 .owner = THIS_MODULE,
495 .llseek = noop_llseek,
496 .unlocked_ioctl = linehandle_ioctl,
498 .compat_ioctl = linehandle_ioctl_compat,
502 static int linehandle_create(struct gpio_device *gdev, void __user *ip)
504 struct gpiohandle_request handlereq;
505 struct linehandle_state *lh;
507 int fd, i, count = 0, ret;
510 if (copy_from_user(&handlereq, ip, sizeof(handlereq)))
512 if ((handlereq.lines == 0) || (handlereq.lines > GPIOHANDLES_MAX))
515 lflags = handlereq.flags;
517 /* Return an error if an unknown flag is set */
518 if (lflags & ~GPIOHANDLE_REQUEST_VALID_FLAGS)
522 * Do not allow OPEN_SOURCE & OPEN_DRAIN flags in a single request. If
523 * the hardware actually supports enabling both at the same time the
524 * electrical result would be disastrous.
526 if ((lflags & GPIOHANDLE_REQUEST_OPEN_DRAIN) &&
527 (lflags & GPIOHANDLE_REQUEST_OPEN_SOURCE))
530 /* OPEN_DRAIN and OPEN_SOURCE flags only make sense for output mode. */
531 if (!(lflags & GPIOHANDLE_REQUEST_OUTPUT) &&
532 ((lflags & GPIOHANDLE_REQUEST_OPEN_DRAIN) ||
533 (lflags & GPIOHANDLE_REQUEST_OPEN_SOURCE)))
536 lh = kzalloc(sizeof(*lh), GFP_KERNEL);
540 get_device(&gdev->dev);
542 /* Make sure this is terminated */
543 handlereq.consumer_label[sizeof(handlereq.consumer_label)-1] = '\0';
544 if (strlen(handlereq.consumer_label)) {
545 lh->label = kstrdup(handlereq.consumer_label,
553 /* Request each GPIO */
554 for (i = 0; i < handlereq.lines; i++) {
555 u32 offset = handlereq.lineoffsets[i];
556 struct gpio_desc *desc;
558 if (offset >= gdev->ngpio) {
563 desc = &gdev->descs[offset];
564 ret = gpiod_request(desc, lh->label);
570 if (lflags & GPIOHANDLE_REQUEST_ACTIVE_LOW)
571 set_bit(FLAG_ACTIVE_LOW, &desc->flags);
572 if (lflags & GPIOHANDLE_REQUEST_OPEN_DRAIN)
573 set_bit(FLAG_OPEN_DRAIN, &desc->flags);
574 if (lflags & GPIOHANDLE_REQUEST_OPEN_SOURCE)
575 set_bit(FLAG_OPEN_SOURCE, &desc->flags);
577 ret = gpiod_set_transitory(desc, false);
582 * Lines have to be requested explicitly for input
583 * or output, else the line will be treated "as is".
585 if (lflags & GPIOHANDLE_REQUEST_OUTPUT) {
586 int val = !!handlereq.default_values[i];
588 ret = gpiod_direction_output(desc, val);
591 } else if (lflags & GPIOHANDLE_REQUEST_INPUT) {
592 ret = gpiod_direction_input(desc);
596 dev_dbg(&gdev->dev, "registered chardev handle for line %d\n",
599 /* Let i point at the last handle */
601 lh->numdescs = handlereq.lines;
603 fd = get_unused_fd_flags(O_RDONLY | O_CLOEXEC);
609 file = anon_inode_getfile("gpio-linehandle",
612 O_RDONLY | O_CLOEXEC);
615 goto out_put_unused_fd;
619 if (copy_to_user(ip, &handlereq, sizeof(handlereq))) {
621 * fput() will trigger the release() callback, so do not go onto
622 * the regular error cleanup path here.
629 fd_install(fd, file);
631 dev_dbg(&gdev->dev, "registered chardev handle for %d lines\n",
639 for (i = 0; i < count; i++)
640 gpiod_free(lh->descs[i]);
644 put_device(&gdev->dev);
649 * GPIO line event management
653 * struct lineevent_state - contains the state of a userspace event
654 * @gdev: the GPIO device the event pertains to
655 * @label: consumer label used to tag descriptors
656 * @desc: the GPIO descriptor held by this event
657 * @eflags: the event flags this line was requested with
658 * @irq: the interrupt that trigger in response to events on this GPIO
659 * @wait: wait queue that handles blocking reads of events
660 * @events: KFIFO for the GPIO events
661 * @read_lock: mutex lock to protect reads from colliding with adding
662 * new events to the FIFO
663 * @timestamp: cache for the timestamp storing it between hardirq
664 * and IRQ thread, used to bring the timestamp close to the actual
667 struct lineevent_state {
668 struct gpio_device *gdev;
670 struct gpio_desc *desc;
673 wait_queue_head_t wait;
674 DECLARE_KFIFO(events, struct gpioevent_data, 16);
675 struct mutex read_lock;
679 #define GPIOEVENT_REQUEST_VALID_FLAGS \
680 (GPIOEVENT_REQUEST_RISING_EDGE | \
681 GPIOEVENT_REQUEST_FALLING_EDGE)
683 static __poll_t lineevent_poll(struct file *filep,
684 struct poll_table_struct *wait)
686 struct lineevent_state *le = filep->private_data;
689 poll_wait(filep, &le->wait, wait);
691 if (!kfifo_is_empty(&le->events))
692 events = EPOLLIN | EPOLLRDNORM;
698 static ssize_t lineevent_read(struct file *filep,
703 struct lineevent_state *le = filep->private_data;
707 if (count < sizeof(struct gpioevent_data))
711 if (kfifo_is_empty(&le->events)) {
712 if (filep->f_flags & O_NONBLOCK)
715 ret = wait_event_interruptible(le->wait,
716 !kfifo_is_empty(&le->events));
721 if (mutex_lock_interruptible(&le->read_lock))
723 ret = kfifo_to_user(&le->events, buf, count, &copied);
724 mutex_unlock(&le->read_lock);
730 * If we couldn't read anything from the fifo (a different
731 * thread might have been faster) we either return -EAGAIN if
732 * the file descriptor is non-blocking, otherwise we go back to
733 * sleep and wait for more data to arrive.
735 if (copied == 0 && (filep->f_flags & O_NONBLOCK))
738 } while (copied == 0);
743 static int lineevent_release(struct inode *inode, struct file *filep)
745 struct lineevent_state *le = filep->private_data;
746 struct gpio_device *gdev = le->gdev;
748 free_irq(le->irq, le);
749 gpiod_free(le->desc);
752 put_device(&gdev->dev);
756 static long lineevent_ioctl(struct file *filep, unsigned int cmd,
759 struct lineevent_state *le = filep->private_data;
760 void __user *ip = (void __user *)arg;
761 struct gpiohandle_data ghd;
764 * We can get the value for an event line but not set it,
765 * because it is input by definition.
767 if (cmd == GPIOHANDLE_GET_LINE_VALUES_IOCTL) {
770 memset(&ghd, 0, sizeof(ghd));
772 val = gpiod_get_value_cansleep(le->desc);
777 if (copy_to_user(ip, &ghd, sizeof(ghd)))
786 static long lineevent_ioctl_compat(struct file *filep, unsigned int cmd,
789 return lineevent_ioctl(filep, cmd, (unsigned long)compat_ptr(arg));
793 static const struct file_operations lineevent_fileops = {
794 .release = lineevent_release,
795 .read = lineevent_read,
796 .poll = lineevent_poll,
797 .owner = THIS_MODULE,
798 .llseek = noop_llseek,
799 .unlocked_ioctl = lineevent_ioctl,
801 .compat_ioctl = lineevent_ioctl_compat,
805 static irqreturn_t lineevent_irq_thread(int irq, void *p)
807 struct lineevent_state *le = p;
808 struct gpioevent_data ge;
811 /* Do not leak kernel stack to userspace */
812 memset(&ge, 0, sizeof(ge));
814 ge.timestamp = le->timestamp;
815 level = gpiod_get_value_cansleep(le->desc);
817 if (le->eflags & GPIOEVENT_REQUEST_RISING_EDGE
818 && le->eflags & GPIOEVENT_REQUEST_FALLING_EDGE) {
820 /* Emit low-to-high event */
821 ge.id = GPIOEVENT_EVENT_RISING_EDGE;
823 /* Emit high-to-low event */
824 ge.id = GPIOEVENT_EVENT_FALLING_EDGE;
825 } else if (le->eflags & GPIOEVENT_REQUEST_RISING_EDGE && level) {
826 /* Emit low-to-high event */
827 ge.id = GPIOEVENT_EVENT_RISING_EDGE;
828 } else if (le->eflags & GPIOEVENT_REQUEST_FALLING_EDGE && !level) {
829 /* Emit high-to-low event */
830 ge.id = GPIOEVENT_EVENT_FALLING_EDGE;
835 ret = kfifo_put(&le->events, ge);
837 wake_up_poll(&le->wait, EPOLLIN);
842 static irqreturn_t lineevent_irq_handler(int irq, void *p)
844 struct lineevent_state *le = p;
847 * Just store the timestamp in hardirq context so we get it as
848 * close in time as possible to the actual event.
850 le->timestamp = ktime_get_real_ns();
852 return IRQ_WAKE_THREAD;
855 static int lineevent_create(struct gpio_device *gdev, void __user *ip)
857 struct gpioevent_request eventreq;
858 struct lineevent_state *le;
859 struct gpio_desc *desc;
868 if (copy_from_user(&eventreq, ip, sizeof(eventreq)))
871 le = kzalloc(sizeof(*le), GFP_KERNEL);
875 get_device(&gdev->dev);
877 /* Make sure this is terminated */
878 eventreq.consumer_label[sizeof(eventreq.consumer_label)-1] = '\0';
879 if (strlen(eventreq.consumer_label)) {
880 le->label = kstrdup(eventreq.consumer_label,
888 offset = eventreq.lineoffset;
889 lflags = eventreq.handleflags;
890 eflags = eventreq.eventflags;
892 if (offset >= gdev->ngpio) {
897 /* Return an error if a unknown flag is set */
898 if ((lflags & ~GPIOHANDLE_REQUEST_VALID_FLAGS) ||
899 (eflags & ~GPIOEVENT_REQUEST_VALID_FLAGS)) {
904 /* This is just wrong: we don't look for events on output lines */
905 if (lflags & GPIOHANDLE_REQUEST_OUTPUT) {
910 desc = &gdev->descs[offset];
911 ret = gpiod_request(desc, le->label);
917 if (lflags & GPIOHANDLE_REQUEST_ACTIVE_LOW)
918 set_bit(FLAG_ACTIVE_LOW, &desc->flags);
919 if (lflags & GPIOHANDLE_REQUEST_OPEN_DRAIN)
920 set_bit(FLAG_OPEN_DRAIN, &desc->flags);
921 if (lflags & GPIOHANDLE_REQUEST_OPEN_SOURCE)
922 set_bit(FLAG_OPEN_SOURCE, &desc->flags);
924 ret = gpiod_direction_input(desc);
928 le->irq = gpiod_to_irq(desc);
934 if (eflags & GPIOEVENT_REQUEST_RISING_EDGE)
935 irqflags |= IRQF_TRIGGER_RISING;
936 if (eflags & GPIOEVENT_REQUEST_FALLING_EDGE)
937 irqflags |= IRQF_TRIGGER_FALLING;
938 irqflags |= IRQF_ONESHOT;
939 irqflags |= IRQF_SHARED;
941 INIT_KFIFO(le->events);
942 init_waitqueue_head(&le->wait);
943 mutex_init(&le->read_lock);
945 /* Request a thread to read the events */
946 ret = request_threaded_irq(le->irq,
947 lineevent_irq_handler,
948 lineevent_irq_thread,
955 fd = get_unused_fd_flags(O_RDONLY | O_CLOEXEC);
961 file = anon_inode_getfile("gpio-event",
964 O_RDONLY | O_CLOEXEC);
967 goto out_put_unused_fd;
971 if (copy_to_user(ip, &eventreq, sizeof(eventreq))) {
973 * fput() will trigger the release() callback, so do not go onto
974 * the regular error cleanup path here.
981 fd_install(fd, file);
988 free_irq(le->irq, le);
990 gpiod_free(le->desc);
995 put_device(&gdev->dev);
1000 * gpio_ioctl() - ioctl handler for the GPIO chardev
1002 static long gpio_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
1004 struct gpio_device *gdev = filp->private_data;
1005 struct gpio_chip *chip = gdev->chip;
1006 void __user *ip = (void __user *)arg;
1008 /* We fail any subsequent ioctl():s when the chip is gone */
1012 /* Fill in the struct and pass to userspace */
1013 if (cmd == GPIO_GET_CHIPINFO_IOCTL) {
1014 struct gpiochip_info chipinfo;
1016 memset(&chipinfo, 0, sizeof(chipinfo));
1018 strncpy(chipinfo.name, dev_name(&gdev->dev),
1019 sizeof(chipinfo.name));
1020 chipinfo.name[sizeof(chipinfo.name)-1] = '\0';
1021 strncpy(chipinfo.label, gdev->label,
1022 sizeof(chipinfo.label));
1023 chipinfo.label[sizeof(chipinfo.label)-1] = '\0';
1024 chipinfo.lines = gdev->ngpio;
1025 if (copy_to_user(ip, &chipinfo, sizeof(chipinfo)))
1028 } else if (cmd == GPIO_GET_LINEINFO_IOCTL) {
1029 struct gpioline_info lineinfo;
1030 struct gpio_desc *desc;
1032 if (copy_from_user(&lineinfo, ip, sizeof(lineinfo)))
1034 if (lineinfo.line_offset >= gdev->ngpio)
1037 desc = &gdev->descs[lineinfo.line_offset];
1039 strncpy(lineinfo.name, desc->name,
1040 sizeof(lineinfo.name));
1041 lineinfo.name[sizeof(lineinfo.name)-1] = '\0';
1043 lineinfo.name[0] = '\0';
1046 strncpy(lineinfo.consumer, desc->label,
1047 sizeof(lineinfo.consumer));
1048 lineinfo.consumer[sizeof(lineinfo.consumer)-1] = '\0';
1050 lineinfo.consumer[0] = '\0';
1054 * Userspace only need to know that the kernel is using
1055 * this GPIO so it can't use it.
1058 if (test_bit(FLAG_REQUESTED, &desc->flags) ||
1059 test_bit(FLAG_IS_HOGGED, &desc->flags) ||
1060 test_bit(FLAG_USED_AS_IRQ, &desc->flags) ||
1061 test_bit(FLAG_EXPORT, &desc->flags) ||
1062 test_bit(FLAG_SYSFS, &desc->flags))
1063 lineinfo.flags |= GPIOLINE_FLAG_KERNEL;
1064 if (test_bit(FLAG_IS_OUT, &desc->flags))
1065 lineinfo.flags |= GPIOLINE_FLAG_IS_OUT;
1066 if (test_bit(FLAG_ACTIVE_LOW, &desc->flags))
1067 lineinfo.flags |= GPIOLINE_FLAG_ACTIVE_LOW;
1068 if (test_bit(FLAG_OPEN_DRAIN, &desc->flags))
1069 lineinfo.flags |= GPIOLINE_FLAG_OPEN_DRAIN;
1070 if (test_bit(FLAG_OPEN_SOURCE, &desc->flags))
1071 lineinfo.flags |= GPIOLINE_FLAG_OPEN_SOURCE;
1073 if (copy_to_user(ip, &lineinfo, sizeof(lineinfo)))
1076 } else if (cmd == GPIO_GET_LINEHANDLE_IOCTL) {
1077 return linehandle_create(gdev, ip);
1078 } else if (cmd == GPIO_GET_LINEEVENT_IOCTL) {
1079 return lineevent_create(gdev, ip);
1084 #ifdef CONFIG_COMPAT
1085 static long gpio_ioctl_compat(struct file *filp, unsigned int cmd,
1088 return gpio_ioctl(filp, cmd, (unsigned long)compat_ptr(arg));
1093 * gpio_chrdev_open() - open the chardev for ioctl operations
1094 * @inode: inode for this chardev
1095 * @filp: file struct for storing private data
1096 * Returns 0 on success
1098 static int gpio_chrdev_open(struct inode *inode, struct file *filp)
1100 struct gpio_device *gdev = container_of(inode->i_cdev,
1101 struct gpio_device, chrdev);
1103 /* Fail on open if the backing gpiochip is gone */
1106 get_device(&gdev->dev);
1107 filp->private_data = gdev;
1109 return nonseekable_open(inode, filp);
1113 * gpio_chrdev_release() - close chardev after ioctl operations
1114 * @inode: inode for this chardev
1115 * @filp: file struct for storing private data
1116 * Returns 0 on success
1118 static int gpio_chrdev_release(struct inode *inode, struct file *filp)
1120 struct gpio_device *gdev = container_of(inode->i_cdev,
1121 struct gpio_device, chrdev);
1123 put_device(&gdev->dev);
1128 static const struct file_operations gpio_fileops = {
1129 .release = gpio_chrdev_release,
1130 .open = gpio_chrdev_open,
1131 .owner = THIS_MODULE,
1132 .llseek = no_llseek,
1133 .unlocked_ioctl = gpio_ioctl,
1134 #ifdef CONFIG_COMPAT
1135 .compat_ioctl = gpio_ioctl_compat,
1139 static void gpiodevice_release(struct device *dev)
1141 struct gpio_device *gdev = dev_get_drvdata(dev);
1143 list_del(&gdev->list);
1144 ida_simple_remove(&gpio_ida, gdev->id);
1145 kfree_const(gdev->label);
1150 static int gpiochip_setup_dev(struct gpio_device *gdev)
1154 cdev_init(&gdev->chrdev, &gpio_fileops);
1155 gdev->chrdev.owner = THIS_MODULE;
1156 gdev->dev.devt = MKDEV(MAJOR(gpio_devt), gdev->id);
1158 status = cdev_device_add(&gdev->chrdev, &gdev->dev);
1162 chip_dbg(gdev->chip, "added GPIO chardev (%d:%d)\n",
1163 MAJOR(gpio_devt), gdev->id);
1165 status = gpiochip_sysfs_register(gdev);
1167 goto err_remove_device;
1169 /* From this point, the .release() function cleans up gpio_device */
1170 gdev->dev.release = gpiodevice_release;
1171 pr_debug("%s: registered GPIOs %d to %d on device: %s (%s)\n",
1172 __func__, gdev->base, gdev->base + gdev->ngpio - 1,
1173 dev_name(&gdev->dev), gdev->chip->label ? : "generic");
1178 cdev_device_del(&gdev->chrdev, &gdev->dev);
1182 static void gpiochip_machine_hog(struct gpio_chip *chip, struct gpiod_hog *hog)
1184 struct gpio_desc *desc;
1187 desc = gpiochip_get_desc(chip, hog->chip_hwnum);
1189 pr_err("%s: unable to get GPIO desc: %ld\n",
1190 __func__, PTR_ERR(desc));
1194 if (test_bit(FLAG_IS_HOGGED, &desc->flags))
1197 rv = gpiod_hog(desc, hog->line_name, hog->lflags, hog->dflags);
1199 pr_err("%s: unable to hog GPIO line (%s:%u): %d\n",
1200 __func__, chip->label, hog->chip_hwnum, rv);
1203 static void machine_gpiochip_add(struct gpio_chip *chip)
1205 struct gpiod_hog *hog;
1207 mutex_lock(&gpio_machine_hogs_mutex);
1209 list_for_each_entry(hog, &gpio_machine_hogs, list) {
1210 if (!strcmp(chip->label, hog->chip_label))
1211 gpiochip_machine_hog(chip, hog);
1214 mutex_unlock(&gpio_machine_hogs_mutex);
1217 static void gpiochip_setup_devs(void)
1219 struct gpio_device *gdev;
1222 list_for_each_entry(gdev, &gpio_devices, list) {
1223 err = gpiochip_setup_dev(gdev);
1225 pr_err("%s: Failed to initialize gpio device (%d)\n",
1226 dev_name(&gdev->dev), err);
1230 int gpiochip_add_data_with_key(struct gpio_chip *chip, void *data,
1231 struct lock_class_key *lock_key,
1232 struct lock_class_key *request_key)
1234 unsigned long flags;
1237 int base = chip->base;
1238 struct gpio_device *gdev;
1241 * First: allocate and populate the internal stat container, and
1242 * set up the struct device.
1244 gdev = kzalloc(sizeof(*gdev), GFP_KERNEL);
1247 gdev->dev.bus = &gpio_bus_type;
1249 chip->gpiodev = gdev;
1251 gdev->dev.parent = chip->parent;
1252 gdev->dev.of_node = chip->parent->of_node;
1255 #ifdef CONFIG_OF_GPIO
1256 /* If the gpiochip has an assigned OF node this takes precedence */
1258 gdev->dev.of_node = chip->of_node;
1261 gdev->id = ida_simple_get(&gpio_ida, 0, 0, GFP_KERNEL);
1266 dev_set_name(&gdev->dev, "gpiochip%d", gdev->id);
1267 device_initialize(&gdev->dev);
1268 dev_set_drvdata(&gdev->dev, gdev);
1269 if (chip->parent && chip->parent->driver)
1270 gdev->owner = chip->parent->driver->owner;
1271 else if (chip->owner)
1272 /* TODO: remove chip->owner */
1273 gdev->owner = chip->owner;
1275 gdev->owner = THIS_MODULE;
1277 gdev->descs = kcalloc(chip->ngpio, sizeof(gdev->descs[0]), GFP_KERNEL);
1283 if (chip->ngpio == 0) {
1284 chip_err(chip, "tried to insert a GPIO chip with zero lines\n");
1286 goto err_free_descs;
1289 if (chip->ngpio > FASTPATH_NGPIO)
1290 chip_warn(chip, "line cnt %u is greater than fast path cnt %u\n",
1291 chip->ngpio, FASTPATH_NGPIO);
1293 gdev->label = kstrdup_const(chip->label ?: "unknown", GFP_KERNEL);
1296 goto err_free_descs;
1299 gdev->ngpio = chip->ngpio;
1302 spin_lock_irqsave(&gpio_lock, flags);
1305 * TODO: this allocates a Linux GPIO number base in the global
1306 * GPIO numberspace for this chip. In the long run we want to
1307 * get *rid* of this numberspace and use only descriptors, but
1308 * it may be a pipe dream. It will not happen before we get rid
1309 * of the sysfs interface anyways.
1312 base = gpiochip_find_base(chip->ngpio);
1315 spin_unlock_irqrestore(&gpio_lock, flags);
1316 goto err_free_label;
1319 * TODO: it should not be necessary to reflect the assigned
1320 * base outside of the GPIO subsystem. Go over drivers and
1321 * see if anyone makes use of this, else drop this and assign
1328 status = gpiodev_add_to_list(gdev);
1330 spin_unlock_irqrestore(&gpio_lock, flags);
1331 goto err_free_label;
1334 spin_unlock_irqrestore(&gpio_lock, flags);
1336 for (i = 0; i < chip->ngpio; i++) {
1337 struct gpio_desc *desc = &gdev->descs[i];
1341 /* REVISIT: most hardware initializes GPIOs as inputs (often
1342 * with pullups enabled) so power usage is minimized. Linux
1343 * code should set the gpio direction first thing; but until
1344 * it does, and in case chip->get_direction is not set, we may
1345 * expose the wrong direction in sysfs.
1347 desc->flags = !chip->direction_input ? (1 << FLAG_IS_OUT) : 0;
1350 #ifdef CONFIG_PINCTRL
1351 INIT_LIST_HEAD(&gdev->pin_ranges);
1354 status = gpiochip_set_desc_names(chip);
1356 goto err_remove_from_list;
1358 status = gpiochip_irqchip_init_valid_mask(chip);
1360 goto err_remove_from_list;
1362 status = gpiochip_init_valid_mask(chip);
1364 goto err_remove_irqchip_mask;
1366 status = gpiochip_add_irqchip(chip, lock_key, request_key);
1368 goto err_remove_chip;
1370 status = of_gpiochip_add(chip);
1372 goto err_remove_chip;
1374 acpi_gpiochip_add(chip);
1376 machine_gpiochip_add(chip);
1379 * By first adding the chardev, and then adding the device,
1380 * we get a device node entry in sysfs under
1381 * /sys/bus/gpio/devices/gpiochipN/dev that can be used for
1382 * coldplug of device nodes and other udev business.
1383 * We can do this only if gpiolib has been initialized.
1384 * Otherwise, defer until later.
1386 if (gpiolib_initialized) {
1387 status = gpiochip_setup_dev(gdev);
1389 goto err_remove_chip;
1394 acpi_gpiochip_remove(chip);
1395 gpiochip_free_hogs(chip);
1396 of_gpiochip_remove(chip);
1397 gpiochip_free_valid_mask(chip);
1398 err_remove_irqchip_mask:
1399 gpiochip_irqchip_free_valid_mask(chip);
1400 err_remove_from_list:
1401 spin_lock_irqsave(&gpio_lock, flags);
1402 list_del(&gdev->list);
1403 spin_unlock_irqrestore(&gpio_lock, flags);
1405 kfree_const(gdev->label);
1409 ida_simple_remove(&gpio_ida, gdev->id);
1410 /* failures here can mean systems won't boot... */
1411 pr_err("%s: GPIOs %d..%d (%s) failed to register\n", __func__,
1412 gdev->base, gdev->base + gdev->ngpio - 1,
1413 chip->label ? : "generic");
1417 EXPORT_SYMBOL_GPL(gpiochip_add_data_with_key);
1420 * gpiochip_get_data() - get per-subdriver data for the chip
1424 * The per-subdriver data for the chip.
1426 void *gpiochip_get_data(struct gpio_chip *chip)
1428 return chip->gpiodev->data;
1430 EXPORT_SYMBOL_GPL(gpiochip_get_data);
1433 * gpiochip_remove() - unregister a gpio_chip
1434 * @chip: the chip to unregister
1436 * A gpio_chip with any GPIOs still requested may not be removed.
1438 void gpiochip_remove(struct gpio_chip *chip)
1440 struct gpio_device *gdev = chip->gpiodev;
1441 struct gpio_desc *desc;
1442 unsigned long flags;
1444 bool requested = false;
1446 /* FIXME: should the legacy sysfs handling be moved to gpio_device? */
1447 gpiochip_sysfs_unregister(gdev);
1448 gpiochip_free_hogs(chip);
1449 /* Numb the device, cancelling all outstanding operations */
1451 gpiochip_irqchip_remove(chip);
1452 acpi_gpiochip_remove(chip);
1453 gpiochip_remove_pin_ranges(chip);
1454 of_gpiochip_remove(chip);
1455 gpiochip_free_valid_mask(chip);
1457 * We accept no more calls into the driver from this point, so
1458 * NULL the driver data pointer
1462 spin_lock_irqsave(&gpio_lock, flags);
1463 for (i = 0; i < gdev->ngpio; i++) {
1464 desc = &gdev->descs[i];
1465 if (test_bit(FLAG_REQUESTED, &desc->flags))
1468 spin_unlock_irqrestore(&gpio_lock, flags);
1471 dev_crit(&gdev->dev,
1472 "REMOVING GPIOCHIP WITH GPIOS STILL REQUESTED\n");
1475 * The gpiochip side puts its use of the device to rest here:
1476 * if there are no userspace clients, the chardev and device will
1477 * be removed, else it will be dangling until the last user is
1480 cdev_device_del(&gdev->chrdev, &gdev->dev);
1481 put_device(&gdev->dev);
1483 EXPORT_SYMBOL_GPL(gpiochip_remove);
1485 static void devm_gpio_chip_release(struct device *dev, void *res)
1487 struct gpio_chip *chip = *(struct gpio_chip **)res;
1489 gpiochip_remove(chip);
1492 static int devm_gpio_chip_match(struct device *dev, void *res, void *data)
1495 struct gpio_chip **r = res;
1506 * devm_gpiochip_add_data() - Resource manager gpiochip_add_data()
1507 * @dev: the device pointer on which irq_chip belongs to.
1508 * @chip: the chip to register, with chip->base initialized
1509 * @data: driver-private data associated with this chip
1511 * Context: potentially before irqs will work
1513 * The gpio chip automatically be released when the device is unbound.
1516 * A negative errno if the chip can't be registered, such as because the
1517 * chip->base is invalid or already associated with a different chip.
1518 * Otherwise it returns zero as a success code.
1520 int devm_gpiochip_add_data(struct device *dev, struct gpio_chip *chip,
1523 struct gpio_chip **ptr;
1526 ptr = devres_alloc(devm_gpio_chip_release, sizeof(*ptr),
1531 ret = gpiochip_add_data(chip, data);
1538 devres_add(dev, ptr);
1542 EXPORT_SYMBOL_GPL(devm_gpiochip_add_data);
1545 * devm_gpiochip_remove() - Resource manager of gpiochip_remove()
1546 * @dev: device for which which resource was allocated
1547 * @chip: the chip to remove
1549 * A gpio_chip with any GPIOs still requested may not be removed.
1551 void devm_gpiochip_remove(struct device *dev, struct gpio_chip *chip)
1555 ret = devres_release(dev, devm_gpio_chip_release,
1556 devm_gpio_chip_match, chip);
1559 EXPORT_SYMBOL_GPL(devm_gpiochip_remove);
1562 * gpiochip_find() - iterator for locating a specific gpio_chip
1563 * @data: data to pass to match function
1564 * @match: Callback function to check gpio_chip
1566 * Similar to bus_find_device. It returns a reference to a gpio_chip as
1567 * determined by a user supplied @match callback. The callback should return
1568 * 0 if the device doesn't match and non-zero if it does. If the callback is
1569 * non-zero, this function will return to the caller and not iterate over any
1572 struct gpio_chip *gpiochip_find(void *data,
1573 int (*match)(struct gpio_chip *chip,
1576 struct gpio_device *gdev;
1577 struct gpio_chip *chip = NULL;
1578 unsigned long flags;
1580 spin_lock_irqsave(&gpio_lock, flags);
1581 list_for_each_entry(gdev, &gpio_devices, list)
1582 if (gdev->chip && match(gdev->chip, data)) {
1587 spin_unlock_irqrestore(&gpio_lock, flags);
1591 EXPORT_SYMBOL_GPL(gpiochip_find);
1593 static int gpiochip_match_name(struct gpio_chip *chip, void *data)
1595 const char *name = data;
1597 return !strcmp(chip->label, name);
1600 static struct gpio_chip *find_chip_by_name(const char *name)
1602 return gpiochip_find((void *)name, gpiochip_match_name);
1605 #ifdef CONFIG_GPIOLIB_IRQCHIP
1608 * The following is irqchip helper code for gpiochips.
1611 static int gpiochip_irqchip_init_valid_mask(struct gpio_chip *gpiochip)
1613 if (!gpiochip->irq.need_valid_mask)
1616 gpiochip->irq.valid_mask = gpiochip_allocate_mask(gpiochip);
1617 if (!gpiochip->irq.valid_mask)
1623 static void gpiochip_irqchip_free_valid_mask(struct gpio_chip *gpiochip)
1625 kfree(gpiochip->irq.valid_mask);
1626 gpiochip->irq.valid_mask = NULL;
1629 bool gpiochip_irqchip_irq_valid(const struct gpio_chip *gpiochip,
1630 unsigned int offset)
1632 if (!gpiochip_line_is_valid(gpiochip, offset))
1634 /* No mask means all valid */
1635 if (likely(!gpiochip->irq.valid_mask))
1637 return test_bit(offset, gpiochip->irq.valid_mask);
1639 EXPORT_SYMBOL_GPL(gpiochip_irqchip_irq_valid);
1642 * gpiochip_set_cascaded_irqchip() - connects a cascaded irqchip to a gpiochip
1643 * @gpiochip: the gpiochip to set the irqchip chain to
1644 * @irqchip: the irqchip to chain to the gpiochip
1645 * @parent_irq: the irq number corresponding to the parent IRQ for this
1647 * @parent_handler: the parent interrupt handler for the accumulated IRQ
1648 * coming out of the gpiochip. If the interrupt is nested rather than
1649 * cascaded, pass NULL in this handler argument
1651 static void gpiochip_set_cascaded_irqchip(struct gpio_chip *gpiochip,
1652 struct irq_chip *irqchip,
1653 unsigned int parent_irq,
1654 irq_flow_handler_t parent_handler)
1656 unsigned int offset;
1658 if (!gpiochip->irq.domain) {
1659 chip_err(gpiochip, "called %s before setting up irqchip\n",
1664 if (parent_handler) {
1665 if (gpiochip->can_sleep) {
1667 "you cannot have chained interrupts on a "
1668 "chip that may sleep\n");
1672 * The parent irqchip is already using the chip_data for this
1673 * irqchip, so our callbacks simply use the handler_data.
1675 irq_set_chained_handler_and_data(parent_irq, parent_handler,
1678 gpiochip->irq.parents = &parent_irq;
1679 gpiochip->irq.num_parents = 1;
1682 /* Set the parent IRQ for all affected IRQs */
1683 for (offset = 0; offset < gpiochip->ngpio; offset++) {
1684 if (!gpiochip_irqchip_irq_valid(gpiochip, offset))
1686 irq_set_parent(irq_find_mapping(gpiochip->irq.domain, offset),
1692 * gpiochip_set_chained_irqchip() - connects a chained irqchip to a gpiochip
1693 * @gpiochip: the gpiochip to set the irqchip chain to
1694 * @irqchip: the irqchip to chain to the gpiochip
1695 * @parent_irq: the irq number corresponding to the parent IRQ for this
1697 * @parent_handler: the parent interrupt handler for the accumulated IRQ
1698 * coming out of the gpiochip. If the interrupt is nested rather than
1699 * cascaded, pass NULL in this handler argument
1701 void gpiochip_set_chained_irqchip(struct gpio_chip *gpiochip,
1702 struct irq_chip *irqchip,
1703 unsigned int parent_irq,
1704 irq_flow_handler_t parent_handler)
1706 if (gpiochip->irq.threaded) {
1707 chip_err(gpiochip, "tried to chain a threaded gpiochip\n");
1711 gpiochip_set_cascaded_irqchip(gpiochip, irqchip, parent_irq,
1714 EXPORT_SYMBOL_GPL(gpiochip_set_chained_irqchip);
1717 * gpiochip_set_nested_irqchip() - connects a nested irqchip to a gpiochip
1718 * @gpiochip: the gpiochip to set the irqchip nested handler to
1719 * @irqchip: the irqchip to nest to the gpiochip
1720 * @parent_irq: the irq number corresponding to the parent IRQ for this
1723 void gpiochip_set_nested_irqchip(struct gpio_chip *gpiochip,
1724 struct irq_chip *irqchip,
1725 unsigned int parent_irq)
1727 gpiochip_set_cascaded_irqchip(gpiochip, irqchip, parent_irq,
1730 EXPORT_SYMBOL_GPL(gpiochip_set_nested_irqchip);
1733 * gpiochip_irq_map() - maps an IRQ into a GPIO irqchip
1734 * @d: the irqdomain used by this irqchip
1735 * @irq: the global irq number used by this GPIO irqchip irq
1736 * @hwirq: the local IRQ/GPIO line offset on this gpiochip
1738 * This function will set up the mapping for a certain IRQ line on a
1739 * gpiochip by assigning the gpiochip as chip data, and using the irqchip
1740 * stored inside the gpiochip.
1742 int gpiochip_irq_map(struct irq_domain *d, unsigned int irq,
1743 irq_hw_number_t hwirq)
1745 struct gpio_chip *chip = d->host_data;
1748 if (!gpiochip_irqchip_irq_valid(chip, hwirq))
1751 irq_set_chip_data(irq, chip);
1753 * This lock class tells lockdep that GPIO irqs are in a different
1754 * category than their parents, so it won't report false recursion.
1756 irq_set_lockdep_class(irq, chip->irq.lock_key, chip->irq.request_key);
1757 irq_set_chip_and_handler(irq, chip->irq.chip, chip->irq.handler);
1758 /* Chips that use nested thread handlers have them marked */
1759 if (chip->irq.threaded)
1760 irq_set_nested_thread(irq, 1);
1761 irq_set_noprobe(irq);
1763 if (chip->irq.num_parents == 1)
1764 err = irq_set_parent(irq, chip->irq.parents[0]);
1765 else if (chip->irq.map)
1766 err = irq_set_parent(irq, chip->irq.map[hwirq]);
1772 * No set-up of the hardware will happen if IRQ_TYPE_NONE
1773 * is passed as default type.
1775 if (chip->irq.default_type != IRQ_TYPE_NONE)
1776 irq_set_irq_type(irq, chip->irq.default_type);
1780 EXPORT_SYMBOL_GPL(gpiochip_irq_map);
1782 void gpiochip_irq_unmap(struct irq_domain *d, unsigned int irq)
1784 struct gpio_chip *chip = d->host_data;
1786 if (chip->irq.threaded)
1787 irq_set_nested_thread(irq, 0);
1788 irq_set_chip_and_handler(irq, NULL, NULL);
1789 irq_set_chip_data(irq, NULL);
1791 EXPORT_SYMBOL_GPL(gpiochip_irq_unmap);
1793 static const struct irq_domain_ops gpiochip_domain_ops = {
1794 .map = gpiochip_irq_map,
1795 .unmap = gpiochip_irq_unmap,
1796 /* Virtually all GPIO irqchips are twocell:ed */
1797 .xlate = irq_domain_xlate_twocell,
1800 static int gpiochip_irq_reqres(struct irq_data *d)
1802 struct gpio_chip *chip = irq_data_get_irq_chip_data(d);
1804 if (!try_module_get(chip->gpiodev->owner))
1807 if (gpiochip_lock_as_irq(chip, d->hwirq)) {
1809 "unable to lock HW IRQ %lu for IRQ\n",
1811 module_put(chip->gpiodev->owner);
1817 static void gpiochip_irq_relres(struct irq_data *d)
1819 struct gpio_chip *chip = irq_data_get_irq_chip_data(d);
1821 gpiochip_unlock_as_irq(chip, d->hwirq);
1822 module_put(chip->gpiodev->owner);
1825 static int gpiochip_to_irq(struct gpio_chip *chip, unsigned offset)
1827 if (!gpiochip_irqchip_irq_valid(chip, offset))
1830 return irq_create_mapping(chip->irq.domain, offset);
1834 * gpiochip_add_irqchip() - adds an IRQ chip to a GPIO chip
1835 * @gpiochip: the GPIO chip to add the IRQ chip to
1836 * @lock_key: lockdep class for IRQ lock
1837 * @request_key: lockdep class for IRQ request
1839 static int gpiochip_add_irqchip(struct gpio_chip *gpiochip,
1840 struct lock_class_key *lock_key,
1841 struct lock_class_key *request_key)
1843 struct irq_chip *irqchip = gpiochip->irq.chip;
1844 const struct irq_domain_ops *ops;
1845 struct device_node *np;
1852 if (gpiochip->irq.parent_handler && gpiochip->can_sleep) {
1853 chip_err(gpiochip, "you cannot have chained interrupts on a "
1854 "chip that may sleep\n");
1858 np = gpiochip->gpiodev->dev.of_node;
1859 type = gpiochip->irq.default_type;
1862 * Specifying a default trigger is a terrible idea if DT or ACPI is
1863 * used to configure the interrupts, as you may end up with
1864 * conflicting triggers. Tell the user, and reset to NONE.
1866 if (WARN(np && type != IRQ_TYPE_NONE,
1867 "%s: Ignoring %u default trigger\n", np->full_name, type))
1868 type = IRQ_TYPE_NONE;
1870 if (has_acpi_companion(gpiochip->parent) && type != IRQ_TYPE_NONE) {
1871 acpi_handle_warn(ACPI_HANDLE(gpiochip->parent),
1872 "Ignoring %u default trigger\n", type);
1873 type = IRQ_TYPE_NONE;
1876 gpiochip->to_irq = gpiochip_to_irq;
1877 gpiochip->irq.default_type = type;
1878 gpiochip->irq.lock_key = lock_key;
1879 gpiochip->irq.request_key = request_key;
1881 if (gpiochip->irq.domain_ops)
1882 ops = gpiochip->irq.domain_ops;
1884 ops = &gpiochip_domain_ops;
1886 gpiochip->irq.domain = irq_domain_add_simple(np, gpiochip->ngpio,
1887 gpiochip->irq.first,
1889 if (!gpiochip->irq.domain)
1893 * It is possible for a driver to override this, but only if the
1894 * alternative functions are both implemented.
1896 if (!irqchip->irq_request_resources &&
1897 !irqchip->irq_release_resources) {
1898 irqchip->irq_request_resources = gpiochip_irq_reqres;
1899 irqchip->irq_release_resources = gpiochip_irq_relres;
1902 if (gpiochip->irq.parent_handler) {
1903 void *data = gpiochip->irq.parent_handler_data ?: gpiochip;
1905 for (i = 0; i < gpiochip->irq.num_parents; i++) {
1907 * The parent IRQ chip is already using the chip_data
1908 * for this IRQ chip, so our callbacks simply use the
1911 irq_set_chained_handler_and_data(gpiochip->irq.parents[i],
1912 gpiochip->irq.parent_handler,
1917 acpi_gpiochip_request_interrupts(gpiochip);
1923 * gpiochip_irqchip_remove() - removes an irqchip added to a gpiochip
1924 * @gpiochip: the gpiochip to remove the irqchip from
1926 * This is called only from gpiochip_remove()
1928 static void gpiochip_irqchip_remove(struct gpio_chip *gpiochip)
1930 unsigned int offset;
1932 acpi_gpiochip_free_interrupts(gpiochip);
1934 if (gpiochip->irq.chip && gpiochip->irq.parent_handler) {
1935 struct gpio_irq_chip *irq = &gpiochip->irq;
1938 for (i = 0; i < irq->num_parents; i++)
1939 irq_set_chained_handler_and_data(irq->parents[i],
1943 /* Remove all IRQ mappings and delete the domain */
1944 if (gpiochip->irq.domain) {
1947 for (offset = 0; offset < gpiochip->ngpio; offset++) {
1948 if (!gpiochip_irqchip_irq_valid(gpiochip, offset))
1951 irq = irq_find_mapping(gpiochip->irq.domain, offset);
1952 irq_dispose_mapping(irq);
1955 irq_domain_remove(gpiochip->irq.domain);
1958 if (gpiochip->irq.chip) {
1959 gpiochip->irq.chip->irq_request_resources = NULL;
1960 gpiochip->irq.chip->irq_release_resources = NULL;
1961 gpiochip->irq.chip = NULL;
1964 gpiochip_irqchip_free_valid_mask(gpiochip);
1968 * gpiochip_irqchip_add_key() - adds an irqchip to a gpiochip
1969 * @gpiochip: the gpiochip to add the irqchip to
1970 * @irqchip: the irqchip to add to the gpiochip
1971 * @first_irq: if not dynamically assigned, the base (first) IRQ to
1972 * allocate gpiochip irqs from
1973 * @handler: the irq handler to use (often a predefined irq core function)
1974 * @type: the default type for IRQs on this irqchip, pass IRQ_TYPE_NONE
1975 * to have the core avoid setting up any default type in the hardware.
1976 * @threaded: whether this irqchip uses a nested thread handler
1977 * @lock_key: lockdep class for IRQ lock
1978 * @request_key: lockdep class for IRQ request
1980 * This function closely associates a certain irqchip with a certain
1981 * gpiochip, providing an irq domain to translate the local IRQs to
1982 * global irqs in the gpiolib core, and making sure that the gpiochip
1983 * is passed as chip data to all related functions. Driver callbacks
1984 * need to use gpiochip_get_data() to get their local state containers back
1985 * from the gpiochip passed as chip data. An irqdomain will be stored
1986 * in the gpiochip that shall be used by the driver to handle IRQ number
1987 * translation. The gpiochip will need to be initialized and registered
1988 * before calling this function.
1990 * This function will handle two cell:ed simple IRQs and assumes all
1991 * the pins on the gpiochip can generate a unique IRQ. Everything else
1992 * need to be open coded.
1994 int gpiochip_irqchip_add_key(struct gpio_chip *gpiochip,
1995 struct irq_chip *irqchip,
1996 unsigned int first_irq,
1997 irq_flow_handler_t handler,
2000 struct lock_class_key *lock_key,
2001 struct lock_class_key *request_key)
2003 struct device_node *of_node;
2005 if (!gpiochip || !irqchip)
2008 if (!gpiochip->parent) {
2009 pr_err("missing gpiochip .dev parent pointer\n");
2012 gpiochip->irq.threaded = threaded;
2013 of_node = gpiochip->parent->of_node;
2014 #ifdef CONFIG_OF_GPIO
2016 * If the gpiochip has an assigned OF node this takes precedence
2017 * FIXME: get rid of this and use gpiochip->parent->of_node
2020 if (gpiochip->of_node)
2021 of_node = gpiochip->of_node;
2024 * Specifying a default trigger is a terrible idea if DT or ACPI is
2025 * used to configure the interrupts, as you may end-up with
2026 * conflicting triggers. Tell the user, and reset to NONE.
2028 if (WARN(of_node && type != IRQ_TYPE_NONE,
2029 "%pOF: Ignoring %d default trigger\n", of_node, type))
2030 type = IRQ_TYPE_NONE;
2031 if (has_acpi_companion(gpiochip->parent) && type != IRQ_TYPE_NONE) {
2032 acpi_handle_warn(ACPI_HANDLE(gpiochip->parent),
2033 "Ignoring %d default trigger\n", type);
2034 type = IRQ_TYPE_NONE;
2037 gpiochip->irq.chip = irqchip;
2038 gpiochip->irq.handler = handler;
2039 gpiochip->irq.default_type = type;
2040 gpiochip->to_irq = gpiochip_to_irq;
2041 gpiochip->irq.lock_key = lock_key;
2042 gpiochip->irq.request_key = request_key;
2043 gpiochip->irq.domain = irq_domain_add_simple(of_node,
2044 gpiochip->ngpio, first_irq,
2045 &gpiochip_domain_ops, gpiochip);
2046 if (!gpiochip->irq.domain) {
2047 gpiochip->irq.chip = NULL;
2052 * It is possible for a driver to override this, but only if the
2053 * alternative functions are both implemented.
2055 if (!irqchip->irq_request_resources &&
2056 !irqchip->irq_release_resources) {
2057 irqchip->irq_request_resources = gpiochip_irq_reqres;
2058 irqchip->irq_release_resources = gpiochip_irq_relres;
2061 acpi_gpiochip_request_interrupts(gpiochip);
2065 EXPORT_SYMBOL_GPL(gpiochip_irqchip_add_key);
2067 #else /* CONFIG_GPIOLIB_IRQCHIP */
2069 static inline int gpiochip_add_irqchip(struct gpio_chip *gpiochip,
2070 struct lock_class_key *lock_key,
2071 struct lock_class_key *request_key)
2076 static void gpiochip_irqchip_remove(struct gpio_chip *gpiochip) {}
2077 static inline int gpiochip_irqchip_init_valid_mask(struct gpio_chip *gpiochip)
2081 static inline void gpiochip_irqchip_free_valid_mask(struct gpio_chip *gpiochip)
2084 #endif /* CONFIG_GPIOLIB_IRQCHIP */
2087 * gpiochip_generic_request() - request the gpio function for a pin
2088 * @chip: the gpiochip owning the GPIO
2089 * @offset: the offset of the GPIO to request for GPIO function
2091 int gpiochip_generic_request(struct gpio_chip *chip, unsigned offset)
2093 return pinctrl_gpio_request(chip->gpiodev->base + offset);
2095 EXPORT_SYMBOL_GPL(gpiochip_generic_request);
2098 * gpiochip_generic_free() - free the gpio function from a pin
2099 * @chip: the gpiochip to request the gpio function for
2100 * @offset: the offset of the GPIO to free from GPIO function
2102 void gpiochip_generic_free(struct gpio_chip *chip, unsigned offset)
2104 pinctrl_gpio_free(chip->gpiodev->base + offset);
2106 EXPORT_SYMBOL_GPL(gpiochip_generic_free);
2109 * gpiochip_generic_config() - apply configuration for a pin
2110 * @chip: the gpiochip owning the GPIO
2111 * @offset: the offset of the GPIO to apply the configuration
2112 * @config: the configuration to be applied
2114 int gpiochip_generic_config(struct gpio_chip *chip, unsigned offset,
2115 unsigned long config)
2117 return pinctrl_gpio_set_config(chip->gpiodev->base + offset, config);
2119 EXPORT_SYMBOL_GPL(gpiochip_generic_config);
2121 #ifdef CONFIG_PINCTRL
2124 * gpiochip_add_pingroup_range() - add a range for GPIO <-> pin mapping
2125 * @chip: the gpiochip to add the range for
2126 * @pctldev: the pin controller to map to
2127 * @gpio_offset: the start offset in the current gpio_chip number space
2128 * @pin_group: name of the pin group inside the pin controller
2130 * Calling this function directly from a DeviceTree-supported
2131 * pinctrl driver is DEPRECATED. Please see Section 2.1 of
2132 * Documentation/devicetree/bindings/gpio/gpio.txt on how to
2133 * bind pinctrl and gpio drivers via the "gpio-ranges" property.
2135 int gpiochip_add_pingroup_range(struct gpio_chip *chip,
2136 struct pinctrl_dev *pctldev,
2137 unsigned int gpio_offset, const char *pin_group)
2139 struct gpio_pin_range *pin_range;
2140 struct gpio_device *gdev = chip->gpiodev;
2143 pin_range = kzalloc(sizeof(*pin_range), GFP_KERNEL);
2145 chip_err(chip, "failed to allocate pin ranges\n");
2149 /* Use local offset as range ID */
2150 pin_range->range.id = gpio_offset;
2151 pin_range->range.gc = chip;
2152 pin_range->range.name = chip->label;
2153 pin_range->range.base = gdev->base + gpio_offset;
2154 pin_range->pctldev = pctldev;
2156 ret = pinctrl_get_group_pins(pctldev, pin_group,
2157 &pin_range->range.pins,
2158 &pin_range->range.npins);
2164 pinctrl_add_gpio_range(pctldev, &pin_range->range);
2166 chip_dbg(chip, "created GPIO range %d->%d ==> %s PINGRP %s\n",
2167 gpio_offset, gpio_offset + pin_range->range.npins - 1,
2168 pinctrl_dev_get_devname(pctldev), pin_group);
2170 list_add_tail(&pin_range->node, &gdev->pin_ranges);
2174 EXPORT_SYMBOL_GPL(gpiochip_add_pingroup_range);
2177 * gpiochip_add_pin_range() - add a range for GPIO <-> pin mapping
2178 * @chip: the gpiochip to add the range for
2179 * @pinctl_name: the dev_name() of the pin controller to map to
2180 * @gpio_offset: the start offset in the current gpio_chip number space
2181 * @pin_offset: the start offset in the pin controller number space
2182 * @npins: the number of pins from the offset of each pin space (GPIO and
2183 * pin controller) to accumulate in this range
2186 * 0 on success, or a negative error-code on failure.
2188 * Calling this function directly from a DeviceTree-supported
2189 * pinctrl driver is DEPRECATED. Please see Section 2.1 of
2190 * Documentation/devicetree/bindings/gpio/gpio.txt on how to
2191 * bind pinctrl and gpio drivers via the "gpio-ranges" property.
2193 int gpiochip_add_pin_range(struct gpio_chip *chip, const char *pinctl_name,
2194 unsigned int gpio_offset, unsigned int pin_offset,
2197 struct gpio_pin_range *pin_range;
2198 struct gpio_device *gdev = chip->gpiodev;
2201 pin_range = kzalloc(sizeof(*pin_range), GFP_KERNEL);
2203 chip_err(chip, "failed to allocate pin ranges\n");
2207 /* Use local offset as range ID */
2208 pin_range->range.id = gpio_offset;
2209 pin_range->range.gc = chip;
2210 pin_range->range.name = chip->label;
2211 pin_range->range.base = gdev->base + gpio_offset;
2212 pin_range->range.pin_base = pin_offset;
2213 pin_range->range.npins = npins;
2214 pin_range->pctldev = pinctrl_find_and_add_gpio_range(pinctl_name,
2216 if (IS_ERR(pin_range->pctldev)) {
2217 ret = PTR_ERR(pin_range->pctldev);
2218 chip_err(chip, "could not create pin range\n");
2222 chip_dbg(chip, "created GPIO range %d->%d ==> %s PIN %d->%d\n",
2223 gpio_offset, gpio_offset + npins - 1,
2225 pin_offset, pin_offset + npins - 1);
2227 list_add_tail(&pin_range->node, &gdev->pin_ranges);
2231 EXPORT_SYMBOL_GPL(gpiochip_add_pin_range);
2234 * gpiochip_remove_pin_ranges() - remove all the GPIO <-> pin mappings
2235 * @chip: the chip to remove all the mappings for
2237 void gpiochip_remove_pin_ranges(struct gpio_chip *chip)
2239 struct gpio_pin_range *pin_range, *tmp;
2240 struct gpio_device *gdev = chip->gpiodev;
2242 list_for_each_entry_safe(pin_range, tmp, &gdev->pin_ranges, node) {
2243 list_del(&pin_range->node);
2244 pinctrl_remove_gpio_range(pin_range->pctldev,
2249 EXPORT_SYMBOL_GPL(gpiochip_remove_pin_ranges);
2251 #endif /* CONFIG_PINCTRL */
2253 /* These "optional" allocation calls help prevent drivers from stomping
2254 * on each other, and help provide better diagnostics in debugfs.
2255 * They're called even less than the "set direction" calls.
2257 static int gpiod_request_commit(struct gpio_desc *desc, const char *label)
2259 struct gpio_chip *chip = desc->gdev->chip;
2261 unsigned long flags;
2263 spin_lock_irqsave(&gpio_lock, flags);
2265 /* NOTE: gpio_request() can be called in early boot,
2266 * before IRQs are enabled, for non-sleeping (SOC) GPIOs.
2269 if (test_and_set_bit(FLAG_REQUESTED, &desc->flags) == 0) {
2270 desc_set_label(desc, label ? : "?");
2277 if (chip->request) {
2278 /* chip->request may sleep */
2279 spin_unlock_irqrestore(&gpio_lock, flags);
2280 status = chip->request(chip, gpio_chip_hwgpio(desc));
2281 spin_lock_irqsave(&gpio_lock, flags);
2284 desc_set_label(desc, NULL);
2285 clear_bit(FLAG_REQUESTED, &desc->flags);
2289 if (chip->get_direction) {
2290 /* chip->get_direction may sleep */
2291 spin_unlock_irqrestore(&gpio_lock, flags);
2292 gpiod_get_direction(desc);
2293 spin_lock_irqsave(&gpio_lock, flags);
2296 spin_unlock_irqrestore(&gpio_lock, flags);
2301 * This descriptor validation needs to be inserted verbatim into each
2302 * function taking a descriptor, so we need to use a preprocessor
2303 * macro to avoid endless duplication. If the desc is NULL it is an
2304 * optional GPIO and calls should just bail out.
2306 static int validate_desc(const struct gpio_desc *desc, const char *func)
2311 pr_warn("%s: invalid GPIO (errorpointer)\n", func);
2312 return PTR_ERR(desc);
2315 pr_warn("%s: invalid GPIO (no device)\n", func);
2318 if (!desc->gdev->chip) {
2319 dev_warn(&desc->gdev->dev,
2320 "%s: backing chip is gone\n", func);
2326 #define VALIDATE_DESC(desc) do { \
2327 int __valid = validate_desc(desc, __func__); \
2332 #define VALIDATE_DESC_VOID(desc) do { \
2333 int __valid = validate_desc(desc, __func__); \
2338 int gpiod_request(struct gpio_desc *desc, const char *label)
2340 int status = -EPROBE_DEFER;
2341 struct gpio_device *gdev;
2343 VALIDATE_DESC(desc);
2346 if (try_module_get(gdev->owner)) {
2347 status = gpiod_request_commit(desc, label);
2349 module_put(gdev->owner);
2351 get_device(&gdev->dev);
2355 gpiod_dbg(desc, "%s: status %d\n", __func__, status);
2360 static bool gpiod_free_commit(struct gpio_desc *desc)
2363 unsigned long flags;
2364 struct gpio_chip *chip;
2368 gpiod_unexport(desc);
2370 spin_lock_irqsave(&gpio_lock, flags);
2372 chip = desc->gdev->chip;
2373 if (chip && test_bit(FLAG_REQUESTED, &desc->flags)) {
2375 spin_unlock_irqrestore(&gpio_lock, flags);
2376 might_sleep_if(chip->can_sleep);
2377 chip->free(chip, gpio_chip_hwgpio(desc));
2378 spin_lock_irqsave(&gpio_lock, flags);
2380 desc_set_label(desc, NULL);
2381 clear_bit(FLAG_ACTIVE_LOW, &desc->flags);
2382 clear_bit(FLAG_REQUESTED, &desc->flags);
2383 clear_bit(FLAG_OPEN_DRAIN, &desc->flags);
2384 clear_bit(FLAG_OPEN_SOURCE, &desc->flags);
2385 clear_bit(FLAG_IS_HOGGED, &desc->flags);
2389 spin_unlock_irqrestore(&gpio_lock, flags);
2393 void gpiod_free(struct gpio_desc *desc)
2395 if (desc && desc->gdev && gpiod_free_commit(desc)) {
2396 module_put(desc->gdev->owner);
2397 put_device(&desc->gdev->dev);
2399 WARN_ON(extra_checks);
2404 * gpiochip_is_requested - return string iff signal was requested
2405 * @chip: controller managing the signal
2406 * @offset: of signal within controller's 0..(ngpio - 1) range
2408 * Returns NULL if the GPIO is not currently requested, else a string.
2409 * The string returned is the label passed to gpio_request(); if none has been
2410 * passed it is a meaningless, non-NULL constant.
2412 * This function is for use by GPIO controller drivers. The label can
2413 * help with diagnostics, and knowing that the signal is used as a GPIO
2414 * can help avoid accidentally multiplexing it to another controller.
2416 const char *gpiochip_is_requested(struct gpio_chip *chip, unsigned offset)
2418 struct gpio_desc *desc;
2420 if (offset >= chip->ngpio)
2423 desc = &chip->gpiodev->descs[offset];
2425 if (test_bit(FLAG_REQUESTED, &desc->flags) == 0)
2429 EXPORT_SYMBOL_GPL(gpiochip_is_requested);
2432 * gpiochip_request_own_desc - Allow GPIO chip to request its own descriptor
2434 * @hwnum: hardware number of the GPIO for which to request the descriptor
2435 * @label: label for the GPIO
2437 * Function allows GPIO chip drivers to request and use their own GPIO
2438 * descriptors via gpiolib API. Difference to gpiod_request() is that this
2439 * function will not increase reference count of the GPIO chip module. This
2440 * allows the GPIO chip module to be unloaded as needed (we assume that the
2441 * GPIO chip driver handles freeing the GPIOs it has requested).
2444 * A pointer to the GPIO descriptor, or an ERR_PTR()-encoded negative error
2447 struct gpio_desc *gpiochip_request_own_desc(struct gpio_chip *chip, u16 hwnum,
2450 struct gpio_desc *desc = gpiochip_get_desc(chip, hwnum);
2454 chip_err(chip, "failed to get GPIO descriptor\n");
2458 err = gpiod_request_commit(desc, label);
2460 return ERR_PTR(err);
2464 EXPORT_SYMBOL_GPL(gpiochip_request_own_desc);
2467 * gpiochip_free_own_desc - Free GPIO requested by the chip driver
2468 * @desc: GPIO descriptor to free
2470 * Function frees the given GPIO requested previously with
2471 * gpiochip_request_own_desc().
2473 void gpiochip_free_own_desc(struct gpio_desc *desc)
2476 gpiod_free_commit(desc);
2478 EXPORT_SYMBOL_GPL(gpiochip_free_own_desc);
2481 * Drivers MUST set GPIO direction before making get/set calls. In
2482 * some cases this is done in early boot, before IRQs are enabled.
2484 * As a rule these aren't called more than once (except for drivers
2485 * using the open-drain emulation idiom) so these are natural places
2486 * to accumulate extra debugging checks. Note that we can't (yet)
2487 * rely on gpio_request() having been called beforehand.
2491 * gpiod_direction_input - set the GPIO direction to input
2492 * @desc: GPIO to set to input
2494 * Set the direction of the passed GPIO to input, such as gpiod_get_value() can
2495 * be called safely on it.
2497 * Return 0 in case of success, else an error code.
2499 int gpiod_direction_input(struct gpio_desc *desc)
2501 struct gpio_chip *chip;
2502 int status = -EINVAL;
2504 VALIDATE_DESC(desc);
2505 chip = desc->gdev->chip;
2507 if (!chip->get || !chip->direction_input) {
2509 "%s: missing get() or direction_input() operations\n",
2514 status = chip->direction_input(chip, gpio_chip_hwgpio(desc));
2516 clear_bit(FLAG_IS_OUT, &desc->flags);
2518 trace_gpio_direction(desc_to_gpio(desc), 1, status);
2522 EXPORT_SYMBOL_GPL(gpiod_direction_input);
2524 static int gpio_set_drive_single_ended(struct gpio_chip *gc, unsigned offset,
2525 enum pin_config_param mode)
2527 unsigned long config = { PIN_CONF_PACKED(mode, 0) };
2529 return gc->set_config ? gc->set_config(gc, offset, config) : -ENOTSUPP;
2532 static int gpiod_direction_output_raw_commit(struct gpio_desc *desc, int value)
2534 struct gpio_chip *gc = desc->gdev->chip;
2538 if (!gc->set || !gc->direction_output) {
2540 "%s: missing set() or direction_output() operations\n",
2545 ret = gc->direction_output(gc, gpio_chip_hwgpio(desc), val);
2547 set_bit(FLAG_IS_OUT, &desc->flags);
2548 trace_gpio_value(desc_to_gpio(desc), 0, val);
2549 trace_gpio_direction(desc_to_gpio(desc), 0, ret);
2554 * gpiod_direction_output_raw - set the GPIO direction to output
2555 * @desc: GPIO to set to output
2556 * @value: initial output value of the GPIO
2558 * Set the direction of the passed GPIO to output, such as gpiod_set_value() can
2559 * be called safely on it. The initial value of the output must be specified
2560 * as raw value on the physical line without regard for the ACTIVE_LOW status.
2562 * Return 0 in case of success, else an error code.
2564 int gpiod_direction_output_raw(struct gpio_desc *desc, int value)
2566 VALIDATE_DESC(desc);
2567 return gpiod_direction_output_raw_commit(desc, value);
2569 EXPORT_SYMBOL_GPL(gpiod_direction_output_raw);
2572 * gpiod_direction_output - set the GPIO direction to output
2573 * @desc: GPIO to set to output
2574 * @value: initial output value of the GPIO
2576 * Set the direction of the passed GPIO to output, such as gpiod_set_value() can
2577 * be called safely on it. The initial value of the output must be specified
2578 * as the logical value of the GPIO, i.e. taking its ACTIVE_LOW status into
2581 * Return 0 in case of success, else an error code.
2583 int gpiod_direction_output(struct gpio_desc *desc, int value)
2585 struct gpio_chip *gc;
2588 VALIDATE_DESC(desc);
2589 if (test_bit(FLAG_ACTIVE_LOW, &desc->flags))
2594 /* GPIOs used for IRQs shall not be set as output */
2595 if (test_bit(FLAG_USED_AS_IRQ, &desc->flags)) {
2597 "%s: tried to set a GPIO tied to an IRQ as output\n",
2602 gc = desc->gdev->chip;
2603 if (test_bit(FLAG_OPEN_DRAIN, &desc->flags)) {
2604 /* First see if we can enable open drain in hardware */
2605 ret = gpio_set_drive_single_ended(gc, gpio_chip_hwgpio(desc),
2606 PIN_CONFIG_DRIVE_OPEN_DRAIN);
2608 goto set_output_value;
2609 /* Emulate open drain by not actively driving the line high */
2611 return gpiod_direction_input(desc);
2613 else if (test_bit(FLAG_OPEN_SOURCE, &desc->flags)) {
2614 ret = gpio_set_drive_single_ended(gc, gpio_chip_hwgpio(desc),
2615 PIN_CONFIG_DRIVE_OPEN_SOURCE);
2617 goto set_output_value;
2618 /* Emulate open source by not actively driving the line low */
2620 return gpiod_direction_input(desc);
2622 gpio_set_drive_single_ended(gc, gpio_chip_hwgpio(desc),
2623 PIN_CONFIG_DRIVE_PUSH_PULL);
2627 return gpiod_direction_output_raw_commit(desc, value);
2629 EXPORT_SYMBOL_GPL(gpiod_direction_output);
2632 * gpiod_set_debounce - sets @debounce time for a GPIO
2633 * @desc: descriptor of the GPIO for which to set debounce time
2634 * @debounce: debounce time in microseconds
2637 * 0 on success, %-ENOTSUPP if the controller doesn't support setting the
2640 int gpiod_set_debounce(struct gpio_desc *desc, unsigned debounce)
2642 struct gpio_chip *chip;
2643 unsigned long config;
2645 VALIDATE_DESC(desc);
2646 chip = desc->gdev->chip;
2647 if (!chip->set || !chip->set_config) {
2649 "%s: missing set() or set_config() operations\n",
2654 config = pinconf_to_config_packed(PIN_CONFIG_INPUT_DEBOUNCE, debounce);
2655 return chip->set_config(chip, gpio_chip_hwgpio(desc), config);
2657 EXPORT_SYMBOL_GPL(gpiod_set_debounce);
2660 * gpiod_set_transitory - Lose or retain GPIO state on suspend or reset
2661 * @desc: descriptor of the GPIO for which to configure persistence
2662 * @transitory: True to lose state on suspend or reset, false for persistence
2665 * 0 on success, otherwise a negative error code.
2667 int gpiod_set_transitory(struct gpio_desc *desc, bool transitory)
2669 struct gpio_chip *chip;
2670 unsigned long packed;
2674 VALIDATE_DESC(desc);
2676 * Handle FLAG_TRANSITORY first, enabling queries to gpiolib for
2677 * persistence state.
2680 set_bit(FLAG_TRANSITORY, &desc->flags);
2682 clear_bit(FLAG_TRANSITORY, &desc->flags);
2684 /* If the driver supports it, set the persistence state now */
2685 chip = desc->gdev->chip;
2686 if (!chip->set_config)
2689 packed = pinconf_to_config_packed(PIN_CONFIG_PERSIST_STATE,
2691 gpio = gpio_chip_hwgpio(desc);
2692 rc = chip->set_config(chip, gpio, packed);
2693 if (rc == -ENOTSUPP) {
2694 dev_dbg(&desc->gdev->dev, "Persistence not supported for GPIO %d\n",
2701 EXPORT_SYMBOL_GPL(gpiod_set_transitory);
2704 * gpiod_is_active_low - test whether a GPIO is active-low or not
2705 * @desc: the gpio descriptor to test
2707 * Returns 1 if the GPIO is active-low, 0 otherwise.
2709 int gpiod_is_active_low(const struct gpio_desc *desc)
2711 VALIDATE_DESC(desc);
2712 return test_bit(FLAG_ACTIVE_LOW, &desc->flags);
2714 EXPORT_SYMBOL_GPL(gpiod_is_active_low);
2716 /* I/O calls are only valid after configuration completed; the relevant
2717 * "is this a valid GPIO" error checks should already have been done.
2719 * "Get" operations are often inlinable as reading a pin value register,
2720 * and masking the relevant bit in that register.
2722 * When "set" operations are inlinable, they involve writing that mask to
2723 * one register to set a low value, or a different register to set it high.
2724 * Otherwise locking is needed, so there may be little value to inlining.
2726 *------------------------------------------------------------------------
2728 * IMPORTANT!!! The hot paths -- get/set value -- assume that callers
2729 * have requested the GPIO. That can include implicit requesting by
2730 * a direction setting call. Marking a gpio as requested locks its chip
2731 * in memory, guaranteeing that these table lookups need no more locking
2732 * and that gpiochip_remove() will fail.
2734 * REVISIT when debugging, consider adding some instrumentation to ensure
2735 * that the GPIO was actually requested.
2738 static int gpiod_get_raw_value_commit(const struct gpio_desc *desc)
2740 struct gpio_chip *chip;
2744 chip = desc->gdev->chip;
2745 offset = gpio_chip_hwgpio(desc);
2746 value = chip->get ? chip->get(chip, offset) : -EIO;
2747 value = value < 0 ? value : !!value;
2748 trace_gpio_value(desc_to_gpio(desc), 1, value);
2752 static int gpio_chip_get_multiple(struct gpio_chip *chip,
2753 unsigned long *mask, unsigned long *bits)
2755 if (chip->get_multiple) {
2756 return chip->get_multiple(chip, mask, bits);
2757 } else if (chip->get) {
2760 for_each_set_bit(i, mask, chip->ngpio) {
2761 value = chip->get(chip, i);
2764 __assign_bit(i, bits, value);
2771 int gpiod_get_array_value_complex(bool raw, bool can_sleep,
2772 unsigned int array_size,
2773 struct gpio_desc **desc_array,
2778 while (i < array_size) {
2779 struct gpio_chip *chip = desc_array[i]->gdev->chip;
2780 unsigned long fastpath[2 * BITS_TO_LONGS(FASTPATH_NGPIO)];
2781 unsigned long *mask, *bits;
2784 if (likely(chip->ngpio <= FASTPATH_NGPIO)) {
2787 mask = kmalloc_array(2 * BITS_TO_LONGS(chip->ngpio),
2789 can_sleep ? GFP_KERNEL : GFP_ATOMIC);
2794 bits = mask + BITS_TO_LONGS(chip->ngpio);
2795 bitmap_zero(mask, chip->ngpio);
2798 WARN_ON(chip->can_sleep);
2800 /* collect all inputs belonging to the same chip */
2803 const struct gpio_desc *desc = desc_array[i];
2804 int hwgpio = gpio_chip_hwgpio(desc);
2806 __set_bit(hwgpio, mask);
2808 } while ((i < array_size) &&
2809 (desc_array[i]->gdev->chip == chip));
2811 ret = gpio_chip_get_multiple(chip, mask, bits);
2813 if (mask != fastpath)
2818 for (j = first; j < i; j++) {
2819 const struct gpio_desc *desc = desc_array[j];
2820 int hwgpio = gpio_chip_hwgpio(desc);
2821 int value = test_bit(hwgpio, bits);
2823 if (!raw && test_bit(FLAG_ACTIVE_LOW, &desc->flags))
2825 value_array[j] = value;
2826 trace_gpio_value(desc_to_gpio(desc), 1, value);
2829 if (mask != fastpath)
2836 * gpiod_get_raw_value() - return a gpio's raw value
2837 * @desc: gpio whose value will be returned
2839 * Return the GPIO's raw value, i.e. the value of the physical line disregarding
2840 * its ACTIVE_LOW status, or negative errno on failure.
2842 * This function should be called from contexts where we cannot sleep, and will
2843 * complain if the GPIO chip functions potentially sleep.
2845 int gpiod_get_raw_value(const struct gpio_desc *desc)
2847 VALIDATE_DESC(desc);
2848 /* Should be using gpio_get_value_cansleep() */
2849 WARN_ON(desc->gdev->chip->can_sleep);
2850 return gpiod_get_raw_value_commit(desc);
2852 EXPORT_SYMBOL_GPL(gpiod_get_raw_value);
2855 * gpiod_get_value() - return a gpio's value
2856 * @desc: gpio whose value will be returned
2858 * Return the GPIO's logical value, i.e. taking the ACTIVE_LOW status into
2859 * account, or negative errno on failure.
2861 * This function should be called from contexts where we cannot sleep, and will
2862 * complain if the GPIO chip functions potentially sleep.
2864 int gpiod_get_value(const struct gpio_desc *desc)
2868 VALIDATE_DESC(desc);
2869 /* Should be using gpio_get_value_cansleep() */
2870 WARN_ON(desc->gdev->chip->can_sleep);
2872 value = gpiod_get_raw_value_commit(desc);
2876 if (test_bit(FLAG_ACTIVE_LOW, &desc->flags))
2881 EXPORT_SYMBOL_GPL(gpiod_get_value);
2884 * gpiod_get_raw_array_value() - read raw values from an array of GPIOs
2885 * @array_size: number of elements in the descriptor / value arrays
2886 * @desc_array: array of GPIO descriptors whose values will be read
2887 * @value_array: array to store the read values
2889 * Read the raw values of the GPIOs, i.e. the values of the physical lines
2890 * without regard for their ACTIVE_LOW status. Return 0 in case of success,
2891 * else an error code.
2893 * This function should be called from contexts where we cannot sleep,
2894 * and it will complain if the GPIO chip functions potentially sleep.
2896 int gpiod_get_raw_array_value(unsigned int array_size,
2897 struct gpio_desc **desc_array, int *value_array)
2901 return gpiod_get_array_value_complex(true, false, array_size,
2902 desc_array, value_array);
2904 EXPORT_SYMBOL_GPL(gpiod_get_raw_array_value);
2907 * gpiod_get_array_value() - read values from an array of GPIOs
2908 * @array_size: number of elements in the descriptor / value arrays
2909 * @desc_array: array of GPIO descriptors whose values will be read
2910 * @value_array: array to store the read values
2912 * Read the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status
2913 * into account. Return 0 in case of success, else an error code.
2915 * This function should be called from contexts where we cannot sleep,
2916 * and it will complain if the GPIO chip functions potentially sleep.
2918 int gpiod_get_array_value(unsigned int array_size,
2919 struct gpio_desc **desc_array, int *value_array)
2923 return gpiod_get_array_value_complex(false, false, array_size,
2924 desc_array, value_array);
2926 EXPORT_SYMBOL_GPL(gpiod_get_array_value);
2929 * gpio_set_open_drain_value_commit() - Set the open drain gpio's value.
2930 * @desc: gpio descriptor whose state need to be set.
2931 * @value: Non-zero for setting it HIGH otherwise it will set to LOW.
2933 static void gpio_set_open_drain_value_commit(struct gpio_desc *desc, bool value)
2936 struct gpio_chip *chip = desc->gdev->chip;
2937 int offset = gpio_chip_hwgpio(desc);
2940 err = chip->direction_input(chip, offset);
2942 clear_bit(FLAG_IS_OUT, &desc->flags);
2944 err = chip->direction_output(chip, offset, 0);
2946 set_bit(FLAG_IS_OUT, &desc->flags);
2948 trace_gpio_direction(desc_to_gpio(desc), value, err);
2951 "%s: Error in set_value for open drain err %d\n",
2956 * _gpio_set_open_source_value() - Set the open source gpio's value.
2957 * @desc: gpio descriptor whose state need to be set.
2958 * @value: Non-zero for setting it HIGH otherwise it will set to LOW.
2960 static void gpio_set_open_source_value_commit(struct gpio_desc *desc, bool value)
2963 struct gpio_chip *chip = desc->gdev->chip;
2964 int offset = gpio_chip_hwgpio(desc);
2967 err = chip->direction_output(chip, offset, 1);
2969 set_bit(FLAG_IS_OUT, &desc->flags);
2971 err = chip->direction_input(chip, offset);
2973 clear_bit(FLAG_IS_OUT, &desc->flags);
2975 trace_gpio_direction(desc_to_gpio(desc), !value, err);
2978 "%s: Error in set_value for open source err %d\n",
2982 static void gpiod_set_raw_value_commit(struct gpio_desc *desc, bool value)
2984 struct gpio_chip *chip;
2986 chip = desc->gdev->chip;
2987 trace_gpio_value(desc_to_gpio(desc), 0, value);
2988 chip->set(chip, gpio_chip_hwgpio(desc), value);
2992 * set multiple outputs on the same chip;
2993 * use the chip's set_multiple function if available;
2994 * otherwise set the outputs sequentially;
2995 * @mask: bit mask array; one bit per output; BITS_PER_LONG bits per word
2996 * defines which outputs are to be changed
2997 * @bits: bit value array; one bit per output; BITS_PER_LONG bits per word
2998 * defines the values the outputs specified by mask are to be set to
3000 static void gpio_chip_set_multiple(struct gpio_chip *chip,
3001 unsigned long *mask, unsigned long *bits)
3003 if (chip->set_multiple) {
3004 chip->set_multiple(chip, mask, bits);
3008 /* set outputs if the corresponding mask bit is set */
3009 for_each_set_bit(i, mask, chip->ngpio)
3010 chip->set(chip, i, test_bit(i, bits));
3014 int gpiod_set_array_value_complex(bool raw, bool can_sleep,
3015 unsigned int array_size,
3016 struct gpio_desc **desc_array,
3021 while (i < array_size) {
3022 struct gpio_chip *chip = desc_array[i]->gdev->chip;
3023 unsigned long fastpath[2 * BITS_TO_LONGS(FASTPATH_NGPIO)];
3024 unsigned long *mask, *bits;
3027 if (likely(chip->ngpio <= FASTPATH_NGPIO)) {
3030 mask = kmalloc_array(2 * BITS_TO_LONGS(chip->ngpio),
3032 can_sleep ? GFP_KERNEL : GFP_ATOMIC);
3037 bits = mask + BITS_TO_LONGS(chip->ngpio);
3038 bitmap_zero(mask, chip->ngpio);
3041 WARN_ON(chip->can_sleep);
3044 struct gpio_desc *desc = desc_array[i];
3045 int hwgpio = gpio_chip_hwgpio(desc);
3046 int value = value_array[i];
3048 if (!raw && test_bit(FLAG_ACTIVE_LOW, &desc->flags))
3050 trace_gpio_value(desc_to_gpio(desc), 0, value);
3052 * collect all normal outputs belonging to the same chip
3053 * open drain and open source outputs are set individually
3055 if (test_bit(FLAG_OPEN_DRAIN, &desc->flags) && !raw) {
3056 gpio_set_open_drain_value_commit(desc, value);
3057 } else if (test_bit(FLAG_OPEN_SOURCE, &desc->flags) && !raw) {
3058 gpio_set_open_source_value_commit(desc, value);
3060 __set_bit(hwgpio, mask);
3062 __set_bit(hwgpio, bits);
3064 __clear_bit(hwgpio, bits);
3068 } while ((i < array_size) &&
3069 (desc_array[i]->gdev->chip == chip));
3070 /* push collected bits to outputs */
3072 gpio_chip_set_multiple(chip, mask, bits);
3074 if (mask != fastpath)
3081 * gpiod_set_raw_value() - assign a gpio's raw value
3082 * @desc: gpio whose value will be assigned
3083 * @value: value to assign
3085 * Set the raw value of the GPIO, i.e. the value of its physical line without
3086 * regard for its ACTIVE_LOW status.
3088 * This function should be called from contexts where we cannot sleep, and will
3089 * complain if the GPIO chip functions potentially sleep.
3091 void gpiod_set_raw_value(struct gpio_desc *desc, int value)
3093 VALIDATE_DESC_VOID(desc);
3094 /* Should be using gpiod_set_value_cansleep() */
3095 WARN_ON(desc->gdev->chip->can_sleep);
3096 gpiod_set_raw_value_commit(desc, value);
3098 EXPORT_SYMBOL_GPL(gpiod_set_raw_value);
3101 * gpiod_set_value_nocheck() - set a GPIO line value without checking
3102 * @desc: the descriptor to set the value on
3103 * @value: value to set
3105 * This sets the value of a GPIO line backing a descriptor, applying
3106 * different semantic quirks like active low and open drain/source
3109 static void gpiod_set_value_nocheck(struct gpio_desc *desc, int value)
3111 if (test_bit(FLAG_ACTIVE_LOW, &desc->flags))
3113 if (test_bit(FLAG_OPEN_DRAIN, &desc->flags))
3114 gpio_set_open_drain_value_commit(desc, value);
3115 else if (test_bit(FLAG_OPEN_SOURCE, &desc->flags))
3116 gpio_set_open_source_value_commit(desc, value);
3118 gpiod_set_raw_value_commit(desc, value);
3122 * gpiod_set_value() - assign a gpio's value
3123 * @desc: gpio whose value will be assigned
3124 * @value: value to assign
3126 * Set the logical value of the GPIO, i.e. taking its ACTIVE_LOW,
3127 * OPEN_DRAIN and OPEN_SOURCE flags into account.
3129 * This function should be called from contexts where we cannot sleep, and will
3130 * complain if the GPIO chip functions potentially sleep.
3132 void gpiod_set_value(struct gpio_desc *desc, int value)
3134 VALIDATE_DESC_VOID(desc);
3135 WARN_ON(desc->gdev->chip->can_sleep);
3136 gpiod_set_value_nocheck(desc, value);
3138 EXPORT_SYMBOL_GPL(gpiod_set_value);
3141 * gpiod_set_raw_array_value() - assign values to an array of GPIOs
3142 * @array_size: number of elements in the descriptor / value arrays
3143 * @desc_array: array of GPIO descriptors whose values will be assigned
3144 * @value_array: array of values to assign
3146 * Set the raw values of the GPIOs, i.e. the values of the physical lines
3147 * without regard for their ACTIVE_LOW status.
3149 * This function should be called from contexts where we cannot sleep, and will
3150 * complain if the GPIO chip functions potentially sleep.
3152 int gpiod_set_raw_array_value(unsigned int array_size,
3153 struct gpio_desc **desc_array, int *value_array)
3157 return gpiod_set_array_value_complex(true, false, array_size,
3158 desc_array, value_array);
3160 EXPORT_SYMBOL_GPL(gpiod_set_raw_array_value);
3163 * gpiod_set_array_value() - assign values to an array of GPIOs
3164 * @array_size: number of elements in the descriptor / value arrays
3165 * @desc_array: array of GPIO descriptors whose values will be assigned
3166 * @value_array: array of values to assign
3168 * Set the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status
3171 * This function should be called from contexts where we cannot sleep, and will
3172 * complain if the GPIO chip functions potentially sleep.
3174 void gpiod_set_array_value(unsigned int array_size,
3175 struct gpio_desc **desc_array, int *value_array)
3179 gpiod_set_array_value_complex(false, false, array_size, desc_array,
3182 EXPORT_SYMBOL_GPL(gpiod_set_array_value);
3185 * gpiod_cansleep() - report whether gpio value access may sleep
3186 * @desc: gpio to check
3189 int gpiod_cansleep(const struct gpio_desc *desc)
3191 VALIDATE_DESC(desc);
3192 return desc->gdev->chip->can_sleep;
3194 EXPORT_SYMBOL_GPL(gpiod_cansleep);
3197 * gpiod_to_irq() - return the IRQ corresponding to a GPIO
3198 * @desc: gpio whose IRQ will be returned (already requested)
3200 * Return the IRQ corresponding to the passed GPIO, or an error code in case of
3203 int gpiod_to_irq(const struct gpio_desc *desc)
3205 struct gpio_chip *chip;
3209 * Cannot VALIDATE_DESC() here as gpiod_to_irq() consumer semantics
3210 * requires this function to not return zero on an invalid descriptor
3211 * but rather a negative error number.
3213 if (!desc || IS_ERR(desc) || !desc->gdev || !desc->gdev->chip)
3216 chip = desc->gdev->chip;
3217 offset = gpio_chip_hwgpio(desc);
3219 int retirq = chip->to_irq(chip, offset);
3221 /* Zero means NO_IRQ */
3229 EXPORT_SYMBOL_GPL(gpiod_to_irq);
3232 * gpiochip_lock_as_irq() - lock a GPIO to be used as IRQ
3233 * @chip: the chip the GPIO to lock belongs to
3234 * @offset: the offset of the GPIO to lock as IRQ
3236 * This is used directly by GPIO drivers that want to lock down
3237 * a certain GPIO line to be used for IRQs.
3239 int gpiochip_lock_as_irq(struct gpio_chip *chip, unsigned int offset)
3241 struct gpio_desc *desc;
3243 desc = gpiochip_get_desc(chip, offset);
3245 return PTR_ERR(desc);
3248 * If it's fast: flush the direction setting if something changed
3251 if (!chip->can_sleep && chip->get_direction) {
3252 int dir = chip->get_direction(chip, offset);
3255 clear_bit(FLAG_IS_OUT, &desc->flags);
3257 set_bit(FLAG_IS_OUT, &desc->flags);
3260 if (test_bit(FLAG_IS_OUT, &desc->flags)) {
3262 "%s: tried to flag a GPIO set as output for IRQ\n",
3267 set_bit(FLAG_USED_AS_IRQ, &desc->flags);
3270 * If the consumer has not set up a label (such as when the
3271 * IRQ is referenced from .to_irq()) we set up a label here
3272 * so it is clear this is used as an interrupt.
3275 desc_set_label(desc, "interrupt");
3279 EXPORT_SYMBOL_GPL(gpiochip_lock_as_irq);
3282 * gpiochip_unlock_as_irq() - unlock a GPIO used as IRQ
3283 * @chip: the chip the GPIO to lock belongs to
3284 * @offset: the offset of the GPIO to lock as IRQ
3286 * This is used directly by GPIO drivers that want to indicate
3287 * that a certain GPIO is no longer used exclusively for IRQ.
3289 void gpiochip_unlock_as_irq(struct gpio_chip *chip, unsigned int offset)
3291 struct gpio_desc *desc;
3293 desc = gpiochip_get_desc(chip, offset);
3297 clear_bit(FLAG_USED_AS_IRQ, &desc->flags);
3299 /* If we only had this marking, erase it */
3300 if (desc->label && !strcmp(desc->label, "interrupt"))
3301 desc_set_label(desc, NULL);
3303 EXPORT_SYMBOL_GPL(gpiochip_unlock_as_irq);
3305 bool gpiochip_line_is_irq(struct gpio_chip *chip, unsigned int offset)
3307 if (offset >= chip->ngpio)
3310 return test_bit(FLAG_USED_AS_IRQ, &chip->gpiodev->descs[offset].flags);
3312 EXPORT_SYMBOL_GPL(gpiochip_line_is_irq);
3314 bool gpiochip_line_is_open_drain(struct gpio_chip *chip, unsigned int offset)
3316 if (offset >= chip->ngpio)
3319 return test_bit(FLAG_OPEN_DRAIN, &chip->gpiodev->descs[offset].flags);
3321 EXPORT_SYMBOL_GPL(gpiochip_line_is_open_drain);
3323 bool gpiochip_line_is_open_source(struct gpio_chip *chip, unsigned int offset)
3325 if (offset >= chip->ngpio)
3328 return test_bit(FLAG_OPEN_SOURCE, &chip->gpiodev->descs[offset].flags);
3330 EXPORT_SYMBOL_GPL(gpiochip_line_is_open_source);
3332 bool gpiochip_line_is_persistent(struct gpio_chip *chip, unsigned int offset)
3334 if (offset >= chip->ngpio)
3337 return !test_bit(FLAG_TRANSITORY, &chip->gpiodev->descs[offset].flags);
3339 EXPORT_SYMBOL_GPL(gpiochip_line_is_persistent);
3342 * gpiod_get_raw_value_cansleep() - return a gpio's raw value
3343 * @desc: gpio whose value will be returned
3345 * Return the GPIO's raw value, i.e. the value of the physical line disregarding
3346 * its ACTIVE_LOW status, or negative errno on failure.
3348 * This function is to be called from contexts that can sleep.
3350 int gpiod_get_raw_value_cansleep(const struct gpio_desc *desc)
3352 might_sleep_if(extra_checks);
3353 VALIDATE_DESC(desc);
3354 return gpiod_get_raw_value_commit(desc);
3356 EXPORT_SYMBOL_GPL(gpiod_get_raw_value_cansleep);
3359 * gpiod_get_value_cansleep() - return a gpio's value
3360 * @desc: gpio whose value will be returned
3362 * Return the GPIO's logical value, i.e. taking the ACTIVE_LOW status into
3363 * account, or negative errno on failure.
3365 * This function is to be called from contexts that can sleep.
3367 int gpiod_get_value_cansleep(const struct gpio_desc *desc)
3371 might_sleep_if(extra_checks);
3372 VALIDATE_DESC(desc);
3373 value = gpiod_get_raw_value_commit(desc);
3377 if (test_bit(FLAG_ACTIVE_LOW, &desc->flags))
3382 EXPORT_SYMBOL_GPL(gpiod_get_value_cansleep);
3385 * gpiod_get_raw_array_value_cansleep() - read raw values from an array of GPIOs
3386 * @array_size: number of elements in the descriptor / value arrays
3387 * @desc_array: array of GPIO descriptors whose values will be read
3388 * @value_array: array to store the read values
3390 * Read the raw values of the GPIOs, i.e. the values of the physical lines
3391 * without regard for their ACTIVE_LOW status. Return 0 in case of success,
3392 * else an error code.
3394 * This function is to be called from contexts that can sleep.
3396 int gpiod_get_raw_array_value_cansleep(unsigned int array_size,
3397 struct gpio_desc **desc_array,
3400 might_sleep_if(extra_checks);
3403 return gpiod_get_array_value_complex(true, true, array_size,
3404 desc_array, value_array);
3406 EXPORT_SYMBOL_GPL(gpiod_get_raw_array_value_cansleep);
3409 * gpiod_get_array_value_cansleep() - read values from an array of GPIOs
3410 * @array_size: number of elements in the descriptor / value arrays
3411 * @desc_array: array of GPIO descriptors whose values will be read
3412 * @value_array: array to store the read values
3414 * Read the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status
3415 * into account. Return 0 in case of success, else an error code.
3417 * This function is to be called from contexts that can sleep.
3419 int gpiod_get_array_value_cansleep(unsigned int array_size,
3420 struct gpio_desc **desc_array,
3423 might_sleep_if(extra_checks);
3426 return gpiod_get_array_value_complex(false, true, array_size,
3427 desc_array, value_array);
3429 EXPORT_SYMBOL_GPL(gpiod_get_array_value_cansleep);
3432 * gpiod_set_raw_value_cansleep() - assign a gpio's raw value
3433 * @desc: gpio whose value will be assigned
3434 * @value: value to assign
3436 * Set the raw value of the GPIO, i.e. the value of its physical line without
3437 * regard for its ACTIVE_LOW status.
3439 * This function is to be called from contexts that can sleep.
3441 void gpiod_set_raw_value_cansleep(struct gpio_desc *desc, int value)
3443 might_sleep_if(extra_checks);
3444 VALIDATE_DESC_VOID(desc);
3445 gpiod_set_raw_value_commit(desc, value);
3447 EXPORT_SYMBOL_GPL(gpiod_set_raw_value_cansleep);
3450 * gpiod_set_value_cansleep() - assign a gpio's value
3451 * @desc: gpio whose value will be assigned
3452 * @value: value to assign
3454 * Set the logical value of the GPIO, i.e. taking its ACTIVE_LOW status into
3457 * This function is to be called from contexts that can sleep.
3459 void gpiod_set_value_cansleep(struct gpio_desc *desc, int value)
3461 might_sleep_if(extra_checks);
3462 VALIDATE_DESC_VOID(desc);
3463 gpiod_set_value_nocheck(desc, value);
3465 EXPORT_SYMBOL_GPL(gpiod_set_value_cansleep);
3468 * gpiod_set_raw_array_value_cansleep() - assign values to an array of GPIOs
3469 * @array_size: number of elements in the descriptor / value arrays
3470 * @desc_array: array of GPIO descriptors whose values will be assigned
3471 * @value_array: array of values to assign
3473 * Set the raw values of the GPIOs, i.e. the values of the physical lines
3474 * without regard for their ACTIVE_LOW status.
3476 * This function is to be called from contexts that can sleep.
3478 int gpiod_set_raw_array_value_cansleep(unsigned int array_size,
3479 struct gpio_desc **desc_array,
3482 might_sleep_if(extra_checks);
3485 return gpiod_set_array_value_complex(true, true, array_size, desc_array,
3488 EXPORT_SYMBOL_GPL(gpiod_set_raw_array_value_cansleep);
3491 * gpiod_add_lookup_tables() - register GPIO device consumers
3492 * @tables: list of tables of consumers to register
3493 * @n: number of tables in the list
3495 void gpiod_add_lookup_tables(struct gpiod_lookup_table **tables, size_t n)
3499 mutex_lock(&gpio_lookup_lock);
3501 for (i = 0; i < n; i++)
3502 list_add_tail(&tables[i]->list, &gpio_lookup_list);
3504 mutex_unlock(&gpio_lookup_lock);
3508 * gpiod_set_array_value_cansleep() - assign values to an array of GPIOs
3509 * @array_size: number of elements in the descriptor / value arrays
3510 * @desc_array: array of GPIO descriptors whose values will be assigned
3511 * @value_array: array of values to assign
3513 * Set the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status
3516 * This function is to be called from contexts that can sleep.
3518 void gpiod_set_array_value_cansleep(unsigned int array_size,
3519 struct gpio_desc **desc_array,
3522 might_sleep_if(extra_checks);
3525 gpiod_set_array_value_complex(false, true, array_size, desc_array,
3528 EXPORT_SYMBOL_GPL(gpiod_set_array_value_cansleep);
3531 * gpiod_add_lookup_table() - register GPIO device consumers
3532 * @table: table of consumers to register
3534 void gpiod_add_lookup_table(struct gpiod_lookup_table *table)
3536 mutex_lock(&gpio_lookup_lock);
3538 list_add_tail(&table->list, &gpio_lookup_list);
3540 mutex_unlock(&gpio_lookup_lock);
3542 EXPORT_SYMBOL_GPL(gpiod_add_lookup_table);
3545 * gpiod_remove_lookup_table() - unregister GPIO device consumers
3546 * @table: table of consumers to unregister
3548 void gpiod_remove_lookup_table(struct gpiod_lookup_table *table)
3550 mutex_lock(&gpio_lookup_lock);
3552 list_del(&table->list);
3554 mutex_unlock(&gpio_lookup_lock);
3556 EXPORT_SYMBOL_GPL(gpiod_remove_lookup_table);
3559 * gpiod_add_hogs() - register a set of GPIO hogs from machine code
3560 * @hogs: table of gpio hog entries with a zeroed sentinel at the end
3562 void gpiod_add_hogs(struct gpiod_hog *hogs)
3564 struct gpio_chip *chip;
3565 struct gpiod_hog *hog;
3567 mutex_lock(&gpio_machine_hogs_mutex);
3569 for (hog = &hogs[0]; hog->chip_label; hog++) {
3570 list_add_tail(&hog->list, &gpio_machine_hogs);
3573 * The chip may have been registered earlier, so check if it
3574 * exists and, if so, try to hog the line now.
3576 chip = find_chip_by_name(hog->chip_label);
3578 gpiochip_machine_hog(chip, hog);
3581 mutex_unlock(&gpio_machine_hogs_mutex);
3583 EXPORT_SYMBOL_GPL(gpiod_add_hogs);
3585 static struct gpiod_lookup_table *gpiod_find_lookup_table(struct device *dev)
3587 const char *dev_id = dev ? dev_name(dev) : NULL;
3588 struct gpiod_lookup_table *table;
3590 mutex_lock(&gpio_lookup_lock);
3592 list_for_each_entry(table, &gpio_lookup_list, list) {
3593 if (table->dev_id && dev_id) {
3595 * Valid strings on both ends, must be identical to have
3598 if (!strcmp(table->dev_id, dev_id))
3602 * One of the pointers is NULL, so both must be to have
3605 if (dev_id == table->dev_id)
3612 mutex_unlock(&gpio_lookup_lock);
3616 static struct gpio_desc *gpiod_find(struct device *dev, const char *con_id,
3618 enum gpio_lookup_flags *flags)
3620 struct gpio_desc *desc = ERR_PTR(-ENOENT);
3621 struct gpiod_lookup_table *table;
3622 struct gpiod_lookup *p;
3624 table = gpiod_find_lookup_table(dev);
3628 for (p = &table->table[0]; p->chip_label; p++) {
3629 struct gpio_chip *chip;
3631 /* idx must always match exactly */
3635 /* If the lookup entry has a con_id, require exact match */
3636 if (p->con_id && (!con_id || strcmp(p->con_id, con_id)))
3639 chip = find_chip_by_name(p->chip_label);
3642 dev_err(dev, "cannot find GPIO chip %s\n",
3644 return ERR_PTR(-ENODEV);
3647 if (chip->ngpio <= p->chip_hwnum) {
3649 "requested GPIO %d is out of range [0..%d] for chip %s\n",
3650 idx, chip->ngpio, chip->label);
3651 return ERR_PTR(-EINVAL);
3654 desc = gpiochip_get_desc(chip, p->chip_hwnum);
3663 static int dt_gpio_count(struct device *dev, const char *con_id)
3669 for (i = 0; i < ARRAY_SIZE(gpio_suffixes); i++) {
3671 snprintf(propname, sizeof(propname), "%s-%s",
3672 con_id, gpio_suffixes[i]);
3674 snprintf(propname, sizeof(propname), "%s",
3677 ret = of_gpio_named_count(dev->of_node, propname);
3681 return ret ? ret : -ENOENT;
3684 static int platform_gpio_count(struct device *dev, const char *con_id)
3686 struct gpiod_lookup_table *table;
3687 struct gpiod_lookup *p;
3688 unsigned int count = 0;
3690 table = gpiod_find_lookup_table(dev);
3694 for (p = &table->table[0]; p->chip_label; p++) {
3695 if ((con_id && p->con_id && !strcmp(con_id, p->con_id)) ||
3696 (!con_id && !p->con_id))
3706 * gpiod_count - return the number of GPIOs associated with a device / function
3707 * or -ENOENT if no GPIO has been assigned to the requested function
3708 * @dev: GPIO consumer, can be NULL for system-global GPIOs
3709 * @con_id: function within the GPIO consumer
3711 int gpiod_count(struct device *dev, const char *con_id)
3713 int count = -ENOENT;
3715 if (IS_ENABLED(CONFIG_OF) && dev && dev->of_node)
3716 count = dt_gpio_count(dev, con_id);
3717 else if (IS_ENABLED(CONFIG_ACPI) && dev && ACPI_HANDLE(dev))
3718 count = acpi_gpio_count(dev, con_id);
3721 count = platform_gpio_count(dev, con_id);
3725 EXPORT_SYMBOL_GPL(gpiod_count);
3728 * gpiod_get - obtain a GPIO for a given GPIO function
3729 * @dev: GPIO consumer, can be NULL for system-global GPIOs
3730 * @con_id: function within the GPIO consumer
3731 * @flags: optional GPIO initialization flags
3733 * Return the GPIO descriptor corresponding to the function con_id of device
3734 * dev, -ENOENT if no GPIO has been assigned to the requested function, or
3735 * another IS_ERR() code if an error occurred while trying to acquire the GPIO.
3737 struct gpio_desc *__must_check gpiod_get(struct device *dev, const char *con_id,
3738 enum gpiod_flags flags)
3740 return gpiod_get_index(dev, con_id, 0, flags);
3742 EXPORT_SYMBOL_GPL(gpiod_get);
3745 * gpiod_get_optional - obtain an optional GPIO for a given GPIO function
3746 * @dev: GPIO consumer, can be NULL for system-global GPIOs
3747 * @con_id: function within the GPIO consumer
3748 * @flags: optional GPIO initialization flags
3750 * This is equivalent to gpiod_get(), except that when no GPIO was assigned to
3751 * the requested function it will return NULL. This is convenient for drivers
3752 * that need to handle optional GPIOs.
3754 struct gpio_desc *__must_check gpiod_get_optional(struct device *dev,
3756 enum gpiod_flags flags)
3758 return gpiod_get_index_optional(dev, con_id, 0, flags);
3760 EXPORT_SYMBOL_GPL(gpiod_get_optional);
3764 * gpiod_configure_flags - helper function to configure a given GPIO
3765 * @desc: gpio whose value will be assigned
3766 * @con_id: function within the GPIO consumer
3767 * @lflags: gpio_lookup_flags - returned from of_find_gpio() or
3769 * @dflags: gpiod_flags - optional GPIO initialization flags
3771 * Return 0 on success, -ENOENT if no GPIO has been assigned to the
3772 * requested function and/or index, or another IS_ERR() code if an error
3773 * occurred while trying to acquire the GPIO.
3775 int gpiod_configure_flags(struct gpio_desc *desc, const char *con_id,
3776 unsigned long lflags, enum gpiod_flags dflags)
3780 if (lflags & GPIO_ACTIVE_LOW)
3781 set_bit(FLAG_ACTIVE_LOW, &desc->flags);
3783 if (lflags & GPIO_OPEN_DRAIN)
3784 set_bit(FLAG_OPEN_DRAIN, &desc->flags);
3785 else if (dflags & GPIOD_FLAGS_BIT_OPEN_DRAIN) {
3787 * This enforces open drain mode from the consumer side.
3788 * This is necessary for some busses like I2C, but the lookup
3789 * should *REALLY* have specified them as open drain in the
3790 * first place, so print a little warning here.
3792 set_bit(FLAG_OPEN_DRAIN, &desc->flags);
3794 "enforced open drain please flag it properly in DT/ACPI DSDT/board file\n");
3797 if (lflags & GPIO_OPEN_SOURCE)
3798 set_bit(FLAG_OPEN_SOURCE, &desc->flags);
3800 status = gpiod_set_transitory(desc, (lflags & GPIO_TRANSITORY));
3804 /* No particular flag request, return here... */
3805 if (!(dflags & GPIOD_FLAGS_BIT_DIR_SET)) {
3806 pr_debug("no flags found for %s\n", con_id);
3811 if (dflags & GPIOD_FLAGS_BIT_DIR_OUT)
3812 status = gpiod_direction_output(desc,
3813 !!(dflags & GPIOD_FLAGS_BIT_DIR_VAL));
3815 status = gpiod_direction_input(desc);
3821 * gpiod_get_index - obtain a GPIO from a multi-index GPIO function
3822 * @dev: GPIO consumer, can be NULL for system-global GPIOs
3823 * @con_id: function within the GPIO consumer
3824 * @idx: index of the GPIO to obtain in the consumer
3825 * @flags: optional GPIO initialization flags
3827 * This variant of gpiod_get() allows to access GPIOs other than the first
3828 * defined one for functions that define several GPIOs.
3830 * Return a valid GPIO descriptor, -ENOENT if no GPIO has been assigned to the
3831 * requested function and/or index, or another IS_ERR() code if an error
3832 * occurred while trying to acquire the GPIO.
3834 struct gpio_desc *__must_check gpiod_get_index(struct device *dev,
3837 enum gpiod_flags flags)
3839 struct gpio_desc *desc = NULL;
3841 enum gpio_lookup_flags lookupflags = 0;
3842 /* Maybe we have a device name, maybe not */
3843 const char *devname = dev ? dev_name(dev) : "?";
3845 dev_dbg(dev, "GPIO lookup for consumer %s\n", con_id);
3848 /* Using device tree? */
3849 if (IS_ENABLED(CONFIG_OF) && dev->of_node) {
3850 dev_dbg(dev, "using device tree for GPIO lookup\n");
3851 desc = of_find_gpio(dev, con_id, idx, &lookupflags);
3852 } else if (ACPI_COMPANION(dev)) {
3853 dev_dbg(dev, "using ACPI for GPIO lookup\n");
3854 desc = acpi_find_gpio(dev, con_id, idx, &flags, &lookupflags);
3859 * Either we are not using DT or ACPI, or their lookup did not return
3860 * a result. In that case, use platform lookup as a fallback.
3862 if (!desc || desc == ERR_PTR(-ENOENT)) {
3863 dev_dbg(dev, "using lookup tables for GPIO lookup\n");
3864 desc = gpiod_find(dev, con_id, idx, &lookupflags);
3868 dev_dbg(dev, "No GPIO consumer %s found\n", con_id);
3873 * If a connection label was passed use that, else attempt to use
3874 * the device name as label
3876 status = gpiod_request(desc, con_id ? con_id : devname);
3878 return ERR_PTR(status);
3880 status = gpiod_configure_flags(desc, con_id, lookupflags, flags);
3882 dev_dbg(dev, "setup of GPIO %s failed\n", con_id);
3884 return ERR_PTR(status);
3889 EXPORT_SYMBOL_GPL(gpiod_get_index);
3892 * gpiod_get_from_of_node() - obtain a GPIO from an OF node
3893 * @node: handle of the OF node
3894 * @propname: name of the DT property representing the GPIO
3895 * @index: index of the GPIO to obtain for the consumer
3896 * @dflags: GPIO initialization flags
3897 * @label: label to attach to the requested GPIO
3900 * On successful request the GPIO pin is configured in accordance with
3901 * provided @dflags. If the node does not have the requested GPIO
3902 * property, NULL is returned.
3904 * In case of error an ERR_PTR() is returned.
3906 struct gpio_desc *gpiod_get_from_of_node(struct device_node *node,
3907 const char *propname, int index,
3908 enum gpiod_flags dflags,
3911 struct gpio_desc *desc;
3912 unsigned long lflags = 0;
3913 enum of_gpio_flags flags;
3914 bool active_low = false;
3915 bool single_ended = false;
3916 bool open_drain = false;
3917 bool transitory = false;
3920 desc = of_get_named_gpiod_flags(node, propname,
3923 if (!desc || IS_ERR(desc)) {
3924 /* If it is not there, just return NULL */
3925 if (PTR_ERR(desc) == -ENOENT)
3930 active_low = flags & OF_GPIO_ACTIVE_LOW;
3931 single_ended = flags & OF_GPIO_SINGLE_ENDED;
3932 open_drain = flags & OF_GPIO_OPEN_DRAIN;
3933 transitory = flags & OF_GPIO_TRANSITORY;
3935 ret = gpiod_request(desc, label);
3937 return ERR_PTR(ret);
3940 lflags |= GPIO_ACTIVE_LOW;
3944 lflags |= GPIO_OPEN_DRAIN;
3946 lflags |= GPIO_OPEN_SOURCE;
3950 lflags |= GPIO_TRANSITORY;
3952 ret = gpiod_configure_flags(desc, propname, lflags, dflags);
3955 return ERR_PTR(ret);
3960 EXPORT_SYMBOL(gpiod_get_from_of_node);
3963 * fwnode_get_named_gpiod - obtain a GPIO from firmware node
3964 * @fwnode: handle of the firmware node
3965 * @propname: name of the firmware property representing the GPIO
3966 * @index: index of the GPIO to obtain for the consumer
3967 * @dflags: GPIO initialization flags
3968 * @label: label to attach to the requested GPIO
3970 * This function can be used for drivers that get their configuration
3971 * from opaque firmware.
3973 * The function properly finds the corresponding GPIO using whatever is the
3974 * underlying firmware interface and then makes sure that the GPIO
3975 * descriptor is requested before it is returned to the caller.
3978 * On successful request the GPIO pin is configured in accordance with
3981 * In case of error an ERR_PTR() is returned.
3983 struct gpio_desc *fwnode_get_named_gpiod(struct fwnode_handle *fwnode,
3984 const char *propname, int index,
3985 enum gpiod_flags dflags,
3988 struct gpio_desc *desc = ERR_PTR(-ENODEV);
3989 unsigned long lflags = 0;
3993 return ERR_PTR(-EINVAL);
3995 if (is_of_node(fwnode)) {
3996 desc = gpiod_get_from_of_node(to_of_node(fwnode),
4001 } else if (is_acpi_node(fwnode)) {
4002 struct acpi_gpio_info info;
4004 desc = acpi_node_get_gpiod(fwnode, propname, index, &info);
4008 acpi_gpio_update_gpiod_flags(&dflags, &info);
4010 if (info.polarity == GPIO_ACTIVE_LOW)
4011 lflags |= GPIO_ACTIVE_LOW;
4014 /* Currently only ACPI takes this path */
4015 ret = gpiod_request(desc, label);
4017 return ERR_PTR(ret);
4019 ret = gpiod_configure_flags(desc, propname, lflags, dflags);
4022 return ERR_PTR(ret);
4027 EXPORT_SYMBOL_GPL(fwnode_get_named_gpiod);
4030 * gpiod_get_index_optional - obtain an optional GPIO from a multi-index GPIO
4032 * @dev: GPIO consumer, can be NULL for system-global GPIOs
4033 * @con_id: function within the GPIO consumer
4034 * @index: index of the GPIO to obtain in the consumer
4035 * @flags: optional GPIO initialization flags
4037 * This is equivalent to gpiod_get_index(), except that when no GPIO with the
4038 * specified index was assigned to the requested function it will return NULL.
4039 * This is convenient for drivers that need to handle optional GPIOs.
4041 struct gpio_desc *__must_check gpiod_get_index_optional(struct device *dev,
4044 enum gpiod_flags flags)
4046 struct gpio_desc *desc;
4048 desc = gpiod_get_index(dev, con_id, index, flags);
4050 if (PTR_ERR(desc) == -ENOENT)
4056 EXPORT_SYMBOL_GPL(gpiod_get_index_optional);
4059 * gpiod_hog - Hog the specified GPIO desc given the provided flags
4060 * @desc: gpio whose value will be assigned
4061 * @name: gpio line name
4062 * @lflags: gpio_lookup_flags - returned from of_find_gpio() or
4064 * @dflags: gpiod_flags - optional GPIO initialization flags
4066 int gpiod_hog(struct gpio_desc *desc, const char *name,
4067 unsigned long lflags, enum gpiod_flags dflags)
4069 struct gpio_chip *chip;
4070 struct gpio_desc *local_desc;
4074 chip = gpiod_to_chip(desc);
4075 hwnum = gpio_chip_hwgpio(desc);
4077 local_desc = gpiochip_request_own_desc(chip, hwnum, name);
4078 if (IS_ERR(local_desc)) {
4079 status = PTR_ERR(local_desc);
4080 pr_err("requesting hog GPIO %s (chip %s, offset %d) failed, %d\n",
4081 name, chip->label, hwnum, status);
4085 status = gpiod_configure_flags(desc, name, lflags, dflags);
4087 pr_err("setup of hog GPIO %s (chip %s, offset %d) failed, %d\n",
4088 name, chip->label, hwnum, status);
4089 gpiochip_free_own_desc(desc);
4093 /* Mark GPIO as hogged so it can be identified and removed later */
4094 set_bit(FLAG_IS_HOGGED, &desc->flags);
4096 pr_info("GPIO line %d (%s) hogged as %s%s\n",
4097 desc_to_gpio(desc), name,
4098 (dflags&GPIOD_FLAGS_BIT_DIR_OUT) ? "output" : "input",
4099 (dflags&GPIOD_FLAGS_BIT_DIR_OUT) ?
4100 (dflags&GPIOD_FLAGS_BIT_DIR_VAL) ? "/high" : "/low":"");
4106 * gpiochip_free_hogs - Scan gpio-controller chip and release GPIO hog
4107 * @chip: gpio chip to act on
4109 * This is only used by of_gpiochip_remove to free hogged gpios
4111 static void gpiochip_free_hogs(struct gpio_chip *chip)
4115 for (id = 0; id < chip->ngpio; id++) {
4116 if (test_bit(FLAG_IS_HOGGED, &chip->gpiodev->descs[id].flags))
4117 gpiochip_free_own_desc(&chip->gpiodev->descs[id]);
4122 * gpiod_get_array - obtain multiple GPIOs from a multi-index GPIO function
4123 * @dev: GPIO consumer, can be NULL for system-global GPIOs
4124 * @con_id: function within the GPIO consumer
4125 * @flags: optional GPIO initialization flags
4127 * This function acquires all the GPIOs defined under a given function.
4129 * Return a struct gpio_descs containing an array of descriptors, -ENOENT if
4130 * no GPIO has been assigned to the requested function, or another IS_ERR()
4131 * code if an error occurred while trying to acquire the GPIOs.
4133 struct gpio_descs *__must_check gpiod_get_array(struct device *dev,
4135 enum gpiod_flags flags)
4137 struct gpio_desc *desc;
4138 struct gpio_descs *descs;
4141 count = gpiod_count(dev, con_id);
4143 return ERR_PTR(count);
4145 descs = kzalloc(struct_size(descs, desc, count), GFP_KERNEL);
4147 return ERR_PTR(-ENOMEM);
4149 for (descs->ndescs = 0; descs->ndescs < count; ) {
4150 desc = gpiod_get_index(dev, con_id, descs->ndescs, flags);
4152 gpiod_put_array(descs);
4153 return ERR_CAST(desc);
4155 descs->desc[descs->ndescs] = desc;
4160 EXPORT_SYMBOL_GPL(gpiod_get_array);
4163 * gpiod_get_array_optional - obtain multiple GPIOs from a multi-index GPIO
4165 * @dev: GPIO consumer, can be NULL for system-global GPIOs
4166 * @con_id: function within the GPIO consumer
4167 * @flags: optional GPIO initialization flags
4169 * This is equivalent to gpiod_get_array(), except that when no GPIO was
4170 * assigned to the requested function it will return NULL.
4172 struct gpio_descs *__must_check gpiod_get_array_optional(struct device *dev,
4174 enum gpiod_flags flags)
4176 struct gpio_descs *descs;
4178 descs = gpiod_get_array(dev, con_id, flags);
4179 if (IS_ERR(descs) && (PTR_ERR(descs) == -ENOENT))
4184 EXPORT_SYMBOL_GPL(gpiod_get_array_optional);
4187 * gpiod_put - dispose of a GPIO descriptor
4188 * @desc: GPIO descriptor to dispose of
4190 * No descriptor can be used after gpiod_put() has been called on it.
4192 void gpiod_put(struct gpio_desc *desc)
4196 EXPORT_SYMBOL_GPL(gpiod_put);
4199 * gpiod_put_array - dispose of multiple GPIO descriptors
4200 * @descs: struct gpio_descs containing an array of descriptors
4202 void gpiod_put_array(struct gpio_descs *descs)
4206 for (i = 0; i < descs->ndescs; i++)
4207 gpiod_put(descs->desc[i]);
4211 EXPORT_SYMBOL_GPL(gpiod_put_array);
4213 static int __init gpiolib_dev_init(void)
4217 /* Register GPIO sysfs bus */
4218 ret = bus_register(&gpio_bus_type);
4220 pr_err("gpiolib: could not register GPIO bus type\n");
4224 ret = alloc_chrdev_region(&gpio_devt, 0, GPIO_DEV_MAX, "gpiochip");
4226 pr_err("gpiolib: failed to allocate char dev region\n");
4227 bus_unregister(&gpio_bus_type);
4229 gpiolib_initialized = true;
4230 gpiochip_setup_devs();
4234 core_initcall(gpiolib_dev_init);
4236 #ifdef CONFIG_DEBUG_FS
4238 static void gpiolib_dbg_show(struct seq_file *s, struct gpio_device *gdev)
4241 struct gpio_chip *chip = gdev->chip;
4242 unsigned gpio = gdev->base;
4243 struct gpio_desc *gdesc = &gdev->descs[0];
4247 for (i = 0; i < gdev->ngpio; i++, gpio++, gdesc++) {
4248 if (!test_bit(FLAG_REQUESTED, &gdesc->flags)) {
4250 seq_printf(s, " gpio-%-3d (%-20.20s)\n",
4256 gpiod_get_direction(gdesc);
4257 is_out = test_bit(FLAG_IS_OUT, &gdesc->flags);
4258 is_irq = test_bit(FLAG_USED_AS_IRQ, &gdesc->flags);
4259 seq_printf(s, " gpio-%-3d (%-20.20s|%-20.20s) %s %s %s",
4260 gpio, gdesc->name ? gdesc->name : "", gdesc->label,
4261 is_out ? "out" : "in ",
4263 ? (chip->get(chip, i) ? "hi" : "lo")
4265 is_irq ? "IRQ" : " ");
4266 seq_printf(s, "\n");
4270 static void *gpiolib_seq_start(struct seq_file *s, loff_t *pos)
4272 unsigned long flags;
4273 struct gpio_device *gdev = NULL;
4274 loff_t index = *pos;
4278 spin_lock_irqsave(&gpio_lock, flags);
4279 list_for_each_entry(gdev, &gpio_devices, list)
4281 spin_unlock_irqrestore(&gpio_lock, flags);
4284 spin_unlock_irqrestore(&gpio_lock, flags);
4289 static void *gpiolib_seq_next(struct seq_file *s, void *v, loff_t *pos)
4291 unsigned long flags;
4292 struct gpio_device *gdev = v;
4295 spin_lock_irqsave(&gpio_lock, flags);
4296 if (list_is_last(&gdev->list, &gpio_devices))
4299 ret = list_entry(gdev->list.next, struct gpio_device, list);
4300 spin_unlock_irqrestore(&gpio_lock, flags);
4308 static void gpiolib_seq_stop(struct seq_file *s, void *v)
4312 static int gpiolib_seq_show(struct seq_file *s, void *v)
4314 struct gpio_device *gdev = v;
4315 struct gpio_chip *chip = gdev->chip;
4316 struct device *parent;
4319 seq_printf(s, "%s%s: (dangling chip)", (char *)s->private,
4320 dev_name(&gdev->dev));
4324 seq_printf(s, "%s%s: GPIOs %d-%d", (char *)s->private,
4325 dev_name(&gdev->dev),
4326 gdev->base, gdev->base + gdev->ngpio - 1);
4327 parent = chip->parent;
4329 seq_printf(s, ", parent: %s/%s",
4330 parent->bus ? parent->bus->name : "no-bus",
4333 seq_printf(s, ", %s", chip->label);
4334 if (chip->can_sleep)
4335 seq_printf(s, ", can sleep");
4336 seq_printf(s, ":\n");
4339 chip->dbg_show(s, chip);
4341 gpiolib_dbg_show(s, gdev);
4346 static const struct seq_operations gpiolib_seq_ops = {
4347 .start = gpiolib_seq_start,
4348 .next = gpiolib_seq_next,
4349 .stop = gpiolib_seq_stop,
4350 .show = gpiolib_seq_show,
4353 static int gpiolib_open(struct inode *inode, struct file *file)
4355 return seq_open(file, &gpiolib_seq_ops);
4358 static const struct file_operations gpiolib_operations = {
4359 .owner = THIS_MODULE,
4360 .open = gpiolib_open,
4362 .llseek = seq_lseek,
4363 .release = seq_release,
4366 static int __init gpiolib_debugfs_init(void)
4368 /* /sys/kernel/debug/gpio */
4369 (void) debugfs_create_file("gpio", S_IFREG | S_IRUGO,
4370 NULL, NULL, &gpiolib_operations);
4373 subsys_initcall(gpiolib_debugfs_init);
4375 #endif /* DEBUG_FS */