1 // SPDX-License-Identifier: GPL-2.0
2 #include <linux/bitmap.h>
3 #include <linux/kernel.h>
4 #include <linux/module.h>
5 #include <linux/interrupt.h>
7 #include <linux/spinlock.h>
8 #include <linux/list.h>
9 #include <linux/device.h>
10 #include <linux/err.h>
11 #include <linux/debugfs.h>
12 #include <linux/seq_file.h>
13 #include <linux/gpio.h>
14 #include <linux/idr.h>
15 #include <linux/slab.h>
16 #include <linux/acpi.h>
17 #include <linux/gpio/driver.h>
18 #include <linux/gpio/machine.h>
19 #include <linux/pinctrl/consumer.h>
20 #include <linux/cdev.h>
22 #include <linux/uaccess.h>
23 #include <linux/compat.h>
24 #include <linux/anon_inodes.h>
25 #include <linux/file.h>
26 #include <linux/kfifo.h>
27 #include <linux/poll.h>
28 #include <linux/timekeeping.h>
29 #include <uapi/linux/gpio.h>
32 #include "gpiolib-of.h"
33 #include "gpiolib-acpi.h"
35 #define CREATE_TRACE_POINTS
36 #include <trace/events/gpio.h>
38 /* Implementation infrastructure for GPIO interfaces.
40 * The GPIO programming interface allows for inlining speed-critical
41 * get/set operations for common cases, so that access to SOC-integrated
42 * GPIOs can sometimes cost only an instruction or two per bit.
46 /* When debugging, extend minimal trust to callers and platform code.
47 * Also emit diagnostic messages that may help initial bringup, when
48 * board setup or driver bugs are most common.
50 * Otherwise, minimize overhead in what may be bitbanging codepaths.
53 #define extra_checks 1
55 #define extra_checks 0
58 /* Device and char device-related information */
59 static DEFINE_IDA(gpio_ida);
60 static dev_t gpio_devt;
61 #define GPIO_DEV_MAX 256 /* 256 GPIO chip devices supported */
62 static struct bus_type gpio_bus_type = {
67 * Number of GPIOs to use for the fast path in set array
69 #define FASTPATH_NGPIO CONFIG_GPIOLIB_FASTPATH_LIMIT
71 /* gpio_lock prevents conflicts during gpio_desc[] table updates.
72 * While any GPIO is requested, its gpio_chip is not removable;
73 * each GPIO's "requested" flag serves as a lock and refcount.
75 DEFINE_SPINLOCK(gpio_lock);
77 static DEFINE_MUTEX(gpio_lookup_lock);
78 static LIST_HEAD(gpio_lookup_list);
79 LIST_HEAD(gpio_devices);
81 static DEFINE_MUTEX(gpio_machine_hogs_mutex);
82 static LIST_HEAD(gpio_machine_hogs);
84 static void gpiochip_free_hogs(struct gpio_chip *chip);
85 static int gpiochip_add_irqchip(struct gpio_chip *gpiochip,
86 struct lock_class_key *lock_key,
87 struct lock_class_key *request_key);
88 static void gpiochip_irqchip_remove(struct gpio_chip *gpiochip);
89 static int gpiochip_irqchip_init_hw(struct gpio_chip *gpiochip);
90 static int gpiochip_irqchip_init_valid_mask(struct gpio_chip *gpiochip);
91 static void gpiochip_irqchip_free_valid_mask(struct gpio_chip *gpiochip);
93 static bool gpiolib_initialized;
95 static inline void desc_set_label(struct gpio_desc *d, const char *label)
101 * gpio_to_desc - Convert a GPIO number to its descriptor
102 * @gpio: global GPIO number
105 * The GPIO descriptor associated with the given GPIO, or %NULL if no GPIO
106 * with the given number exists in the system.
108 struct gpio_desc *gpio_to_desc(unsigned gpio)
110 struct gpio_device *gdev;
113 spin_lock_irqsave(&gpio_lock, flags);
115 list_for_each_entry(gdev, &gpio_devices, list) {
116 if (gdev->base <= gpio &&
117 gdev->base + gdev->ngpio > gpio) {
118 spin_unlock_irqrestore(&gpio_lock, flags);
119 return &gdev->descs[gpio - gdev->base];
123 spin_unlock_irqrestore(&gpio_lock, flags);
125 if (!gpio_is_valid(gpio))
126 WARN(1, "invalid GPIO %d\n", gpio);
130 EXPORT_SYMBOL_GPL(gpio_to_desc);
133 * gpiochip_get_desc - get the GPIO descriptor corresponding to the given
134 * hardware number for this chip
136 * @hwnum: hardware number of the GPIO for this chip
139 * A pointer to the GPIO descriptor or %ERR_PTR(-EINVAL) if no GPIO exists
140 * in the given chip for the specified hardware number.
142 struct gpio_desc *gpiochip_get_desc(struct gpio_chip *chip,
145 struct gpio_device *gdev = chip->gpiodev;
147 if (hwnum >= gdev->ngpio)
148 return ERR_PTR(-EINVAL);
150 return &gdev->descs[hwnum];
154 * desc_to_gpio - convert a GPIO descriptor to the integer namespace
155 * @desc: GPIO descriptor
157 * This should disappear in the future but is needed since we still
158 * use GPIO numbers for error messages and sysfs nodes.
161 * The global GPIO number for the GPIO specified by its descriptor.
163 int desc_to_gpio(const struct gpio_desc *desc)
165 return desc->gdev->base + (desc - &desc->gdev->descs[0]);
167 EXPORT_SYMBOL_GPL(desc_to_gpio);
171 * gpiod_to_chip - Return the GPIO chip to which a GPIO descriptor belongs
172 * @desc: descriptor to return the chip of
174 struct gpio_chip *gpiod_to_chip(const struct gpio_desc *desc)
176 if (!desc || !desc->gdev)
178 return desc->gdev->chip;
180 EXPORT_SYMBOL_GPL(gpiod_to_chip);
182 /* dynamic allocation of GPIOs, e.g. on a hotplugged device */
183 static int gpiochip_find_base(int ngpio)
185 struct gpio_device *gdev;
186 int base = ARCH_NR_GPIOS - ngpio;
188 list_for_each_entry_reverse(gdev, &gpio_devices, list) {
189 /* found a free space? */
190 if (gdev->base + gdev->ngpio <= base)
193 /* nope, check the space right before the chip */
194 base = gdev->base - ngpio;
197 if (gpio_is_valid(base)) {
198 pr_debug("%s: found new base at %d\n", __func__, base);
201 pr_err("%s: cannot find free range\n", __func__);
207 * gpiod_get_direction - return the current direction of a GPIO
208 * @desc: GPIO to get the direction of
210 * Returns 0 for output, 1 for input, or an error code in case of error.
212 * This function may sleep if gpiod_cansleep() is true.
214 int gpiod_get_direction(struct gpio_desc *desc)
216 struct gpio_chip *chip;
220 chip = gpiod_to_chip(desc);
221 offset = gpio_chip_hwgpio(desc);
223 if (!chip->get_direction)
226 ret = chip->get_direction(chip, offset);
228 /* GPIOF_DIR_IN, or other positive */
230 clear_bit(FLAG_IS_OUT, &desc->flags);
234 set_bit(FLAG_IS_OUT, &desc->flags);
238 EXPORT_SYMBOL_GPL(gpiod_get_direction);
241 * Add a new chip to the global chips list, keeping the list of chips sorted
242 * by range(means [base, base + ngpio - 1]) order.
244 * Return -EBUSY if the new chip overlaps with some other chip's integer
247 static int gpiodev_add_to_list(struct gpio_device *gdev)
249 struct gpio_device *prev, *next;
251 if (list_empty(&gpio_devices)) {
252 /* initial entry in list */
253 list_add_tail(&gdev->list, &gpio_devices);
257 next = list_entry(gpio_devices.next, struct gpio_device, list);
258 if (gdev->base + gdev->ngpio <= next->base) {
259 /* add before first entry */
260 list_add(&gdev->list, &gpio_devices);
264 prev = list_entry(gpio_devices.prev, struct gpio_device, list);
265 if (prev->base + prev->ngpio <= gdev->base) {
266 /* add behind last entry */
267 list_add_tail(&gdev->list, &gpio_devices);
271 list_for_each_entry_safe(prev, next, &gpio_devices, list) {
272 /* at the end of the list */
273 if (&next->list == &gpio_devices)
276 /* add between prev and next */
277 if (prev->base + prev->ngpio <= gdev->base
278 && gdev->base + gdev->ngpio <= next->base) {
279 list_add(&gdev->list, &prev->list);
284 dev_err(&gdev->dev, "GPIO integer space overlap, cannot add chip\n");
289 * Convert a GPIO name to its descriptor
291 static struct gpio_desc *gpio_name_to_desc(const char * const name)
293 struct gpio_device *gdev;
296 spin_lock_irqsave(&gpio_lock, flags);
298 list_for_each_entry(gdev, &gpio_devices, list) {
301 for (i = 0; i != gdev->ngpio; ++i) {
302 struct gpio_desc *desc = &gdev->descs[i];
304 if (!desc->name || !name)
307 if (!strcmp(desc->name, name)) {
308 spin_unlock_irqrestore(&gpio_lock, flags);
314 spin_unlock_irqrestore(&gpio_lock, flags);
320 * Takes the names from gc->names and checks if they are all unique. If they
321 * are, they are assigned to their gpio descriptors.
323 * Warning if one of the names is already used for a different GPIO.
325 static int gpiochip_set_desc_names(struct gpio_chip *gc)
327 struct gpio_device *gdev = gc->gpiodev;
333 /* First check all names if they are unique */
334 for (i = 0; i != gc->ngpio; ++i) {
335 struct gpio_desc *gpio;
337 gpio = gpio_name_to_desc(gc->names[i]);
340 "Detected name collision for GPIO name '%s'\n",
344 /* Then add all names to the GPIO descriptors */
345 for (i = 0; i != gc->ngpio; ++i)
346 gdev->descs[i].name = gc->names[i];
351 static unsigned long *gpiochip_allocate_mask(struct gpio_chip *chip)
355 p = bitmap_alloc(chip->ngpio, GFP_KERNEL);
359 /* Assume by default all GPIOs are valid */
360 bitmap_fill(p, chip->ngpio);
365 static int gpiochip_alloc_valid_mask(struct gpio_chip *gc)
367 if (!(of_gpio_need_valid_mask(gc) || gc->init_valid_mask))
370 gc->valid_mask = gpiochip_allocate_mask(gc);
377 static int gpiochip_init_valid_mask(struct gpio_chip *gc)
379 if (gc->init_valid_mask)
380 return gc->init_valid_mask(gc,
387 static void gpiochip_free_valid_mask(struct gpio_chip *gpiochip)
389 bitmap_free(gpiochip->valid_mask);
390 gpiochip->valid_mask = NULL;
393 static int gpiochip_add_pin_ranges(struct gpio_chip *gc)
395 if (gc->add_pin_ranges)
396 return gc->add_pin_ranges(gc);
401 bool gpiochip_line_is_valid(const struct gpio_chip *gpiochip,
404 /* No mask means all valid */
405 if (likely(!gpiochip->valid_mask))
407 return test_bit(offset, gpiochip->valid_mask);
409 EXPORT_SYMBOL_GPL(gpiochip_line_is_valid);
412 * GPIO line handle management
416 * struct linehandle_state - contains the state of a userspace handle
417 * @gdev: the GPIO device the handle pertains to
418 * @label: consumer label used to tag descriptors
419 * @descs: the GPIO descriptors held by this handle
420 * @numdescs: the number of descriptors held in the descs array
422 struct linehandle_state {
423 struct gpio_device *gdev;
425 struct gpio_desc *descs[GPIOHANDLES_MAX];
429 #define GPIOHANDLE_REQUEST_VALID_FLAGS \
430 (GPIOHANDLE_REQUEST_INPUT | \
431 GPIOHANDLE_REQUEST_OUTPUT | \
432 GPIOHANDLE_REQUEST_ACTIVE_LOW | \
433 GPIOHANDLE_REQUEST_BIAS_PULL_UP | \
434 GPIOHANDLE_REQUEST_BIAS_PULL_DOWN | \
435 GPIOHANDLE_REQUEST_BIAS_DISABLE | \
436 GPIOHANDLE_REQUEST_OPEN_DRAIN | \
437 GPIOHANDLE_REQUEST_OPEN_SOURCE)
439 static int linehandle_validate_flags(u32 flags)
441 /* Return an error if an unknown flag is set */
442 if (flags & ~GPIOHANDLE_REQUEST_VALID_FLAGS)
446 * Do not allow both INPUT & OUTPUT flags to be set as they are
449 if ((flags & GPIOHANDLE_REQUEST_INPUT) &&
450 (flags & GPIOHANDLE_REQUEST_OUTPUT))
454 * Do not allow OPEN_SOURCE & OPEN_DRAIN flags in a single request. If
455 * the hardware actually supports enabling both at the same time the
456 * electrical result would be disastrous.
458 if ((flags & GPIOHANDLE_REQUEST_OPEN_DRAIN) &&
459 (flags & GPIOHANDLE_REQUEST_OPEN_SOURCE))
462 /* OPEN_DRAIN and OPEN_SOURCE flags only make sense for output mode. */
463 if (!(flags & GPIOHANDLE_REQUEST_OUTPUT) &&
464 ((flags & GPIOHANDLE_REQUEST_OPEN_DRAIN) ||
465 (flags & GPIOHANDLE_REQUEST_OPEN_SOURCE)))
468 /* Bias flags only allowed for input or output mode. */
469 if (!((flags & GPIOHANDLE_REQUEST_INPUT) ||
470 (flags & GPIOHANDLE_REQUEST_OUTPUT)) &&
471 ((flags & GPIOHANDLE_REQUEST_BIAS_DISABLE) ||
472 (flags & GPIOHANDLE_REQUEST_BIAS_PULL_UP) ||
473 (flags & GPIOHANDLE_REQUEST_BIAS_PULL_DOWN)))
476 /* Only one bias flag can be set. */
477 if (((flags & GPIOHANDLE_REQUEST_BIAS_DISABLE) &&
478 (flags & (GPIOHANDLE_REQUEST_BIAS_PULL_DOWN |
479 GPIOHANDLE_REQUEST_BIAS_PULL_UP))) ||
480 ((flags & GPIOHANDLE_REQUEST_BIAS_PULL_DOWN) &&
481 (flags & GPIOHANDLE_REQUEST_BIAS_PULL_UP)))
487 static void linehandle_configure_flag(unsigned long *flagsp,
488 u32 bit, bool active)
491 set_bit(bit, flagsp);
493 clear_bit(bit, flagsp);
496 static long linehandle_set_config(struct linehandle_state *lh,
499 struct gpiohandle_config gcnf;
500 struct gpio_desc *desc;
503 unsigned long *flagsp;
505 if (copy_from_user(&gcnf, ip, sizeof(gcnf)))
509 ret = linehandle_validate_flags(lflags);
513 for (i = 0; i < lh->numdescs; i++) {
515 flagsp = &desc->flags;
517 linehandle_configure_flag(flagsp, FLAG_ACTIVE_LOW,
518 lflags & GPIOHANDLE_REQUEST_ACTIVE_LOW);
520 linehandle_configure_flag(flagsp, FLAG_OPEN_DRAIN,
521 lflags & GPIOHANDLE_REQUEST_OPEN_DRAIN);
523 linehandle_configure_flag(flagsp, FLAG_OPEN_SOURCE,
524 lflags & GPIOHANDLE_REQUEST_OPEN_SOURCE);
526 linehandle_configure_flag(flagsp, FLAG_PULL_UP,
527 lflags & GPIOHANDLE_REQUEST_BIAS_PULL_UP);
529 linehandle_configure_flag(flagsp, FLAG_PULL_DOWN,
530 lflags & GPIOHANDLE_REQUEST_BIAS_PULL_DOWN);
532 linehandle_configure_flag(flagsp, FLAG_BIAS_DISABLE,
533 lflags & GPIOHANDLE_REQUEST_BIAS_DISABLE);
536 * Lines have to be requested explicitly for input
537 * or output, else the line will be treated "as is".
539 if (lflags & GPIOHANDLE_REQUEST_OUTPUT) {
540 int val = !!gcnf.default_values[i];
542 ret = gpiod_direction_output(desc, val);
545 } else if (lflags & GPIOHANDLE_REQUEST_INPUT) {
546 ret = gpiod_direction_input(desc);
554 static long linehandle_ioctl(struct file *filep, unsigned int cmd,
557 struct linehandle_state *lh = filep->private_data;
558 void __user *ip = (void __user *)arg;
559 struct gpiohandle_data ghd;
560 DECLARE_BITMAP(vals, GPIOHANDLES_MAX);
563 if (cmd == GPIOHANDLE_GET_LINE_VALUES_IOCTL) {
564 /* NOTE: It's ok to read values of output lines. */
565 int ret = gpiod_get_array_value_complex(false,
574 memset(&ghd, 0, sizeof(ghd));
575 for (i = 0; i < lh->numdescs; i++)
576 ghd.values[i] = test_bit(i, vals);
578 if (copy_to_user(ip, &ghd, sizeof(ghd)))
582 } else if (cmd == GPIOHANDLE_SET_LINE_VALUES_IOCTL) {
584 * All line descriptors were created at once with the same
585 * flags so just check if the first one is really output.
587 if (!test_bit(FLAG_IS_OUT, &lh->descs[0]->flags))
590 if (copy_from_user(&ghd, ip, sizeof(ghd)))
593 /* Clamp all values to [0,1] */
594 for (i = 0; i < lh->numdescs; i++)
595 __assign_bit(i, vals, ghd.values[i]);
597 /* Reuse the array setting function */
598 return gpiod_set_array_value_complex(false,
604 } else if (cmd == GPIOHANDLE_SET_CONFIG_IOCTL) {
605 return linehandle_set_config(lh, ip);
611 static long linehandle_ioctl_compat(struct file *filep, unsigned int cmd,
614 return linehandle_ioctl(filep, cmd, (unsigned long)compat_ptr(arg));
618 static int linehandle_release(struct inode *inode, struct file *filep)
620 struct linehandle_state *lh = filep->private_data;
621 struct gpio_device *gdev = lh->gdev;
624 for (i = 0; i < lh->numdescs; i++)
625 gpiod_free(lh->descs[i]);
628 put_device(&gdev->dev);
632 static const struct file_operations linehandle_fileops = {
633 .release = linehandle_release,
634 .owner = THIS_MODULE,
635 .llseek = noop_llseek,
636 .unlocked_ioctl = linehandle_ioctl,
638 .compat_ioctl = linehandle_ioctl_compat,
642 static int linehandle_create(struct gpio_device *gdev, void __user *ip)
644 struct gpiohandle_request handlereq;
645 struct linehandle_state *lh;
647 int fd, i, count = 0, ret;
650 if (copy_from_user(&handlereq, ip, sizeof(handlereq)))
652 if ((handlereq.lines == 0) || (handlereq.lines > GPIOHANDLES_MAX))
655 lflags = handlereq.flags;
657 ret = linehandle_validate_flags(lflags);
661 lh = kzalloc(sizeof(*lh), GFP_KERNEL);
665 get_device(&gdev->dev);
667 /* Make sure this is terminated */
668 handlereq.consumer_label[sizeof(handlereq.consumer_label)-1] = '\0';
669 if (strlen(handlereq.consumer_label)) {
670 lh->label = kstrdup(handlereq.consumer_label,
678 /* Request each GPIO */
679 for (i = 0; i < handlereq.lines; i++) {
680 u32 offset = handlereq.lineoffsets[i];
681 struct gpio_desc *desc;
683 if (offset >= gdev->ngpio) {
688 desc = &gdev->descs[offset];
689 ret = gpiod_request(desc, lh->label);
695 if (lflags & GPIOHANDLE_REQUEST_ACTIVE_LOW)
696 set_bit(FLAG_ACTIVE_LOW, &desc->flags);
697 if (lflags & GPIOHANDLE_REQUEST_OPEN_DRAIN)
698 set_bit(FLAG_OPEN_DRAIN, &desc->flags);
699 if (lflags & GPIOHANDLE_REQUEST_OPEN_SOURCE)
700 set_bit(FLAG_OPEN_SOURCE, &desc->flags);
701 if (lflags & GPIOHANDLE_REQUEST_BIAS_DISABLE)
702 set_bit(FLAG_BIAS_DISABLE, &desc->flags);
703 if (lflags & GPIOHANDLE_REQUEST_BIAS_PULL_DOWN)
704 set_bit(FLAG_PULL_DOWN, &desc->flags);
705 if (lflags & GPIOHANDLE_REQUEST_BIAS_PULL_UP)
706 set_bit(FLAG_PULL_UP, &desc->flags);
708 ret = gpiod_set_transitory(desc, false);
713 * Lines have to be requested explicitly for input
714 * or output, else the line will be treated "as is".
716 if (lflags & GPIOHANDLE_REQUEST_OUTPUT) {
717 int val = !!handlereq.default_values[i];
719 ret = gpiod_direction_output(desc, val);
722 } else if (lflags & GPIOHANDLE_REQUEST_INPUT) {
723 ret = gpiod_direction_input(desc);
727 dev_dbg(&gdev->dev, "registered chardev handle for line %d\n",
730 /* Let i point at the last handle */
732 lh->numdescs = handlereq.lines;
734 fd = get_unused_fd_flags(O_RDONLY | O_CLOEXEC);
740 file = anon_inode_getfile("gpio-linehandle",
743 O_RDONLY | O_CLOEXEC);
746 goto out_put_unused_fd;
750 if (copy_to_user(ip, &handlereq, sizeof(handlereq))) {
752 * fput() will trigger the release() callback, so do not go onto
753 * the regular error cleanup path here.
760 fd_install(fd, file);
762 dev_dbg(&gdev->dev, "registered chardev handle for %d lines\n",
770 for (i = 0; i < count; i++)
771 gpiod_free(lh->descs[i]);
775 put_device(&gdev->dev);
780 * GPIO line event management
784 * struct lineevent_state - contains the state of a userspace event
785 * @gdev: the GPIO device the event pertains to
786 * @label: consumer label used to tag descriptors
787 * @desc: the GPIO descriptor held by this event
788 * @eflags: the event flags this line was requested with
789 * @irq: the interrupt that trigger in response to events on this GPIO
790 * @wait: wait queue that handles blocking reads of events
791 * @events: KFIFO for the GPIO events
792 * @read_lock: mutex lock to protect reads from colliding with adding
793 * new events to the FIFO
794 * @timestamp: cache for the timestamp storing it between hardirq
795 * and IRQ thread, used to bring the timestamp close to the actual
798 struct lineevent_state {
799 struct gpio_device *gdev;
801 struct gpio_desc *desc;
804 wait_queue_head_t wait;
805 DECLARE_KFIFO(events, struct gpioevent_data, 16);
806 struct mutex read_lock;
810 #define GPIOEVENT_REQUEST_VALID_FLAGS \
811 (GPIOEVENT_REQUEST_RISING_EDGE | \
812 GPIOEVENT_REQUEST_FALLING_EDGE)
814 static __poll_t lineevent_poll(struct file *filep,
815 struct poll_table_struct *wait)
817 struct lineevent_state *le = filep->private_data;
820 poll_wait(filep, &le->wait, wait);
822 if (!kfifo_is_empty(&le->events))
823 events = EPOLLIN | EPOLLRDNORM;
829 static ssize_t lineevent_read(struct file *filep,
834 struct lineevent_state *le = filep->private_data;
838 if (count < sizeof(struct gpioevent_data))
842 if (kfifo_is_empty(&le->events)) {
843 if (filep->f_flags & O_NONBLOCK)
846 ret = wait_event_interruptible(le->wait,
847 !kfifo_is_empty(&le->events));
852 if (mutex_lock_interruptible(&le->read_lock))
854 ret = kfifo_to_user(&le->events, buf, count, &copied);
855 mutex_unlock(&le->read_lock);
861 * If we couldn't read anything from the fifo (a different
862 * thread might have been faster) we either return -EAGAIN if
863 * the file descriptor is non-blocking, otherwise we go back to
864 * sleep and wait for more data to arrive.
866 if (copied == 0 && (filep->f_flags & O_NONBLOCK))
869 } while (copied == 0);
874 static int lineevent_release(struct inode *inode, struct file *filep)
876 struct lineevent_state *le = filep->private_data;
877 struct gpio_device *gdev = le->gdev;
879 free_irq(le->irq, le);
880 gpiod_free(le->desc);
883 put_device(&gdev->dev);
887 static long lineevent_ioctl(struct file *filep, unsigned int cmd,
890 struct lineevent_state *le = filep->private_data;
891 void __user *ip = (void __user *)arg;
892 struct gpiohandle_data ghd;
895 * We can get the value for an event line but not set it,
896 * because it is input by definition.
898 if (cmd == GPIOHANDLE_GET_LINE_VALUES_IOCTL) {
901 memset(&ghd, 0, sizeof(ghd));
903 val = gpiod_get_value_cansleep(le->desc);
908 if (copy_to_user(ip, &ghd, sizeof(ghd)))
917 static long lineevent_ioctl_compat(struct file *filep, unsigned int cmd,
920 return lineevent_ioctl(filep, cmd, (unsigned long)compat_ptr(arg));
924 static const struct file_operations lineevent_fileops = {
925 .release = lineevent_release,
926 .read = lineevent_read,
927 .poll = lineevent_poll,
928 .owner = THIS_MODULE,
929 .llseek = noop_llseek,
930 .unlocked_ioctl = lineevent_ioctl,
932 .compat_ioctl = lineevent_ioctl_compat,
936 static irqreturn_t lineevent_irq_thread(int irq, void *p)
938 struct lineevent_state *le = p;
939 struct gpioevent_data ge;
942 /* Do not leak kernel stack to userspace */
943 memset(&ge, 0, sizeof(ge));
946 * We may be running from a nested threaded interrupt in which case
947 * we didn't get the timestamp from lineevent_irq_handler().
950 ge.timestamp = ktime_get_real_ns();
952 ge.timestamp = le->timestamp;
954 if (le->eflags & GPIOEVENT_REQUEST_RISING_EDGE
955 && le->eflags & GPIOEVENT_REQUEST_FALLING_EDGE) {
956 int level = gpiod_get_value_cansleep(le->desc);
958 /* Emit low-to-high event */
959 ge.id = GPIOEVENT_EVENT_RISING_EDGE;
961 /* Emit high-to-low event */
962 ge.id = GPIOEVENT_EVENT_FALLING_EDGE;
963 } else if (le->eflags & GPIOEVENT_REQUEST_RISING_EDGE) {
964 /* Emit low-to-high event */
965 ge.id = GPIOEVENT_EVENT_RISING_EDGE;
966 } else if (le->eflags & GPIOEVENT_REQUEST_FALLING_EDGE) {
967 /* Emit high-to-low event */
968 ge.id = GPIOEVENT_EVENT_FALLING_EDGE;
973 ret = kfifo_put(&le->events, ge);
975 wake_up_poll(&le->wait, EPOLLIN);
980 static irqreturn_t lineevent_irq_handler(int irq, void *p)
982 struct lineevent_state *le = p;
985 * Just store the timestamp in hardirq context so we get it as
986 * close in time as possible to the actual event.
988 le->timestamp = ktime_get_real_ns();
990 return IRQ_WAKE_THREAD;
993 static int lineevent_create(struct gpio_device *gdev, void __user *ip)
995 struct gpioevent_request eventreq;
996 struct lineevent_state *le;
997 struct gpio_desc *desc;
1006 if (copy_from_user(&eventreq, ip, sizeof(eventreq)))
1009 offset = eventreq.lineoffset;
1010 lflags = eventreq.handleflags;
1011 eflags = eventreq.eventflags;
1013 if (offset >= gdev->ngpio)
1016 /* Return an error if a unknown flag is set */
1017 if ((lflags & ~GPIOHANDLE_REQUEST_VALID_FLAGS) ||
1018 (eflags & ~GPIOEVENT_REQUEST_VALID_FLAGS))
1021 /* This is just wrong: we don't look for events on output lines */
1022 if ((lflags & GPIOHANDLE_REQUEST_OUTPUT) ||
1023 (lflags & GPIOHANDLE_REQUEST_OPEN_DRAIN) ||
1024 (lflags & GPIOHANDLE_REQUEST_OPEN_SOURCE))
1027 /* Only one bias flag can be set. */
1028 if (((lflags & GPIOHANDLE_REQUEST_BIAS_DISABLE) &&
1029 (lflags & (GPIOHANDLE_REQUEST_BIAS_PULL_DOWN |
1030 GPIOHANDLE_REQUEST_BIAS_PULL_UP))) ||
1031 ((lflags & GPIOHANDLE_REQUEST_BIAS_PULL_DOWN) &&
1032 (lflags & GPIOHANDLE_REQUEST_BIAS_PULL_UP)))
1035 le = kzalloc(sizeof(*le), GFP_KERNEL);
1039 get_device(&gdev->dev);
1041 /* Make sure this is terminated */
1042 eventreq.consumer_label[sizeof(eventreq.consumer_label)-1] = '\0';
1043 if (strlen(eventreq.consumer_label)) {
1044 le->label = kstrdup(eventreq.consumer_label,
1052 desc = &gdev->descs[offset];
1053 ret = gpiod_request(desc, le->label);
1055 goto out_free_label;
1057 le->eflags = eflags;
1059 if (lflags & GPIOHANDLE_REQUEST_ACTIVE_LOW)
1060 set_bit(FLAG_ACTIVE_LOW, &desc->flags);
1061 if (lflags & GPIOHANDLE_REQUEST_BIAS_DISABLE)
1062 set_bit(FLAG_BIAS_DISABLE, &desc->flags);
1063 if (lflags & GPIOHANDLE_REQUEST_BIAS_PULL_DOWN)
1064 set_bit(FLAG_PULL_DOWN, &desc->flags);
1065 if (lflags & GPIOHANDLE_REQUEST_BIAS_PULL_UP)
1066 set_bit(FLAG_PULL_UP, &desc->flags);
1068 ret = gpiod_direction_input(desc);
1072 le->irq = gpiod_to_irq(desc);
1078 if (eflags & GPIOEVENT_REQUEST_RISING_EDGE)
1079 irqflags |= test_bit(FLAG_ACTIVE_LOW, &desc->flags) ?
1080 IRQF_TRIGGER_FALLING : IRQF_TRIGGER_RISING;
1081 if (eflags & GPIOEVENT_REQUEST_FALLING_EDGE)
1082 irqflags |= test_bit(FLAG_ACTIVE_LOW, &desc->flags) ?
1083 IRQF_TRIGGER_RISING : IRQF_TRIGGER_FALLING;
1084 irqflags |= IRQF_ONESHOT;
1086 INIT_KFIFO(le->events);
1087 init_waitqueue_head(&le->wait);
1088 mutex_init(&le->read_lock);
1090 /* Request a thread to read the events */
1091 ret = request_threaded_irq(le->irq,
1092 lineevent_irq_handler,
1093 lineevent_irq_thread,
1100 fd = get_unused_fd_flags(O_RDONLY | O_CLOEXEC);
1106 file = anon_inode_getfile("gpio-event",
1109 O_RDONLY | O_CLOEXEC);
1111 ret = PTR_ERR(file);
1112 goto out_put_unused_fd;
1116 if (copy_to_user(ip, &eventreq, sizeof(eventreq))) {
1118 * fput() will trigger the release() callback, so do not go onto
1119 * the regular error cleanup path here.
1126 fd_install(fd, file);
1133 free_irq(le->irq, le);
1135 gpiod_free(le->desc);
1140 put_device(&gdev->dev);
1145 * gpio_ioctl() - ioctl handler for the GPIO chardev
1147 static long gpio_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
1149 struct gpio_device *gdev = filp->private_data;
1150 struct gpio_chip *chip = gdev->chip;
1151 void __user *ip = (void __user *)arg;
1153 /* We fail any subsequent ioctl():s when the chip is gone */
1157 /* Fill in the struct and pass to userspace */
1158 if (cmd == GPIO_GET_CHIPINFO_IOCTL) {
1159 struct gpiochip_info chipinfo;
1161 memset(&chipinfo, 0, sizeof(chipinfo));
1163 strncpy(chipinfo.name, dev_name(&gdev->dev),
1164 sizeof(chipinfo.name));
1165 chipinfo.name[sizeof(chipinfo.name)-1] = '\0';
1166 strncpy(chipinfo.label, gdev->label,
1167 sizeof(chipinfo.label));
1168 chipinfo.label[sizeof(chipinfo.label)-1] = '\0';
1169 chipinfo.lines = gdev->ngpio;
1170 if (copy_to_user(ip, &chipinfo, sizeof(chipinfo)))
1173 } else if (cmd == GPIO_GET_LINEINFO_IOCTL) {
1174 struct gpioline_info lineinfo;
1175 struct gpio_desc *desc;
1177 if (copy_from_user(&lineinfo, ip, sizeof(lineinfo)))
1179 if (lineinfo.line_offset >= gdev->ngpio)
1182 desc = &gdev->descs[lineinfo.line_offset];
1184 strncpy(lineinfo.name, desc->name,
1185 sizeof(lineinfo.name));
1186 lineinfo.name[sizeof(lineinfo.name)-1] = '\0';
1188 lineinfo.name[0] = '\0';
1191 strncpy(lineinfo.consumer, desc->label,
1192 sizeof(lineinfo.consumer));
1193 lineinfo.consumer[sizeof(lineinfo.consumer)-1] = '\0';
1195 lineinfo.consumer[0] = '\0';
1199 * Userspace only need to know that the kernel is using
1200 * this GPIO so it can't use it.
1203 if (test_bit(FLAG_REQUESTED, &desc->flags) ||
1204 test_bit(FLAG_IS_HOGGED, &desc->flags) ||
1205 test_bit(FLAG_USED_AS_IRQ, &desc->flags) ||
1206 test_bit(FLAG_EXPORT, &desc->flags) ||
1207 test_bit(FLAG_SYSFS, &desc->flags) ||
1208 !pinctrl_gpio_can_use_line(chip->base + lineinfo.line_offset))
1209 lineinfo.flags |= GPIOLINE_FLAG_KERNEL;
1210 if (test_bit(FLAG_IS_OUT, &desc->flags))
1211 lineinfo.flags |= GPIOLINE_FLAG_IS_OUT;
1212 if (test_bit(FLAG_ACTIVE_LOW, &desc->flags))
1213 lineinfo.flags |= GPIOLINE_FLAG_ACTIVE_LOW;
1214 if (test_bit(FLAG_OPEN_DRAIN, &desc->flags))
1215 lineinfo.flags |= (GPIOLINE_FLAG_OPEN_DRAIN |
1216 GPIOLINE_FLAG_IS_OUT);
1217 if (test_bit(FLAG_OPEN_SOURCE, &desc->flags))
1218 lineinfo.flags |= (GPIOLINE_FLAG_OPEN_SOURCE |
1219 GPIOLINE_FLAG_IS_OUT);
1220 if (test_bit(FLAG_BIAS_DISABLE, &desc->flags))
1221 lineinfo.flags |= GPIOLINE_FLAG_BIAS_DISABLE;
1222 if (test_bit(FLAG_PULL_DOWN, &desc->flags))
1223 lineinfo.flags |= GPIOLINE_FLAG_BIAS_PULL_DOWN;
1224 if (test_bit(FLAG_PULL_UP, &desc->flags))
1225 lineinfo.flags |= GPIOLINE_FLAG_BIAS_PULL_UP;
1227 if (copy_to_user(ip, &lineinfo, sizeof(lineinfo)))
1230 } else if (cmd == GPIO_GET_LINEHANDLE_IOCTL) {
1231 return linehandle_create(gdev, ip);
1232 } else if (cmd == GPIO_GET_LINEEVENT_IOCTL) {
1233 return lineevent_create(gdev, ip);
1238 #ifdef CONFIG_COMPAT
1239 static long gpio_ioctl_compat(struct file *filp, unsigned int cmd,
1242 return gpio_ioctl(filp, cmd, (unsigned long)compat_ptr(arg));
1247 * gpio_chrdev_open() - open the chardev for ioctl operations
1248 * @inode: inode for this chardev
1249 * @filp: file struct for storing private data
1250 * Returns 0 on success
1252 static int gpio_chrdev_open(struct inode *inode, struct file *filp)
1254 struct gpio_device *gdev = container_of(inode->i_cdev,
1255 struct gpio_device, chrdev);
1257 /* Fail on open if the backing gpiochip is gone */
1260 get_device(&gdev->dev);
1261 filp->private_data = gdev;
1263 return nonseekable_open(inode, filp);
1267 * gpio_chrdev_release() - close chardev after ioctl operations
1268 * @inode: inode for this chardev
1269 * @filp: file struct for storing private data
1270 * Returns 0 on success
1272 static int gpio_chrdev_release(struct inode *inode, struct file *filp)
1274 struct gpio_device *gdev = container_of(inode->i_cdev,
1275 struct gpio_device, chrdev);
1277 put_device(&gdev->dev);
1282 static const struct file_operations gpio_fileops = {
1283 .release = gpio_chrdev_release,
1284 .open = gpio_chrdev_open,
1285 .owner = THIS_MODULE,
1286 .llseek = no_llseek,
1287 .unlocked_ioctl = gpio_ioctl,
1288 #ifdef CONFIG_COMPAT
1289 .compat_ioctl = gpio_ioctl_compat,
1293 static void gpiodevice_release(struct device *dev)
1295 struct gpio_device *gdev = dev_get_drvdata(dev);
1297 list_del(&gdev->list);
1298 ida_simple_remove(&gpio_ida, gdev->id);
1299 kfree_const(gdev->label);
1304 static int gpiochip_setup_dev(struct gpio_device *gdev)
1308 cdev_init(&gdev->chrdev, &gpio_fileops);
1309 gdev->chrdev.owner = THIS_MODULE;
1310 gdev->dev.devt = MKDEV(MAJOR(gpio_devt), gdev->id);
1312 ret = cdev_device_add(&gdev->chrdev, &gdev->dev);
1316 chip_dbg(gdev->chip, "added GPIO chardev (%d:%d)\n",
1317 MAJOR(gpio_devt), gdev->id);
1319 ret = gpiochip_sysfs_register(gdev);
1321 goto err_remove_device;
1323 /* From this point, the .release() function cleans up gpio_device */
1324 gdev->dev.release = gpiodevice_release;
1325 pr_debug("%s: registered GPIOs %d to %d on device: %s (%s)\n",
1326 __func__, gdev->base, gdev->base + gdev->ngpio - 1,
1327 dev_name(&gdev->dev), gdev->chip->label ? : "generic");
1332 cdev_device_del(&gdev->chrdev, &gdev->dev);
1336 static void gpiochip_machine_hog(struct gpio_chip *chip, struct gpiod_hog *hog)
1338 struct gpio_desc *desc;
1341 desc = gpiochip_get_desc(chip, hog->chip_hwnum);
1343 pr_err("%s: unable to get GPIO desc: %ld\n",
1344 __func__, PTR_ERR(desc));
1348 if (test_bit(FLAG_IS_HOGGED, &desc->flags))
1351 rv = gpiod_hog(desc, hog->line_name, hog->lflags, hog->dflags);
1353 pr_err("%s: unable to hog GPIO line (%s:%u): %d\n",
1354 __func__, chip->label, hog->chip_hwnum, rv);
1357 static void machine_gpiochip_add(struct gpio_chip *chip)
1359 struct gpiod_hog *hog;
1361 mutex_lock(&gpio_machine_hogs_mutex);
1363 list_for_each_entry(hog, &gpio_machine_hogs, list) {
1364 if (!strcmp(chip->label, hog->chip_label))
1365 gpiochip_machine_hog(chip, hog);
1368 mutex_unlock(&gpio_machine_hogs_mutex);
1371 static void gpiochip_setup_devs(void)
1373 struct gpio_device *gdev;
1376 list_for_each_entry(gdev, &gpio_devices, list) {
1377 ret = gpiochip_setup_dev(gdev);
1379 pr_err("%s: Failed to initialize gpio device (%d)\n",
1380 dev_name(&gdev->dev), ret);
1384 int gpiochip_add_data_with_key(struct gpio_chip *chip, void *data,
1385 struct lock_class_key *lock_key,
1386 struct lock_class_key *request_key)
1388 unsigned long flags;
1391 int base = chip->base;
1392 struct gpio_device *gdev;
1395 * First: allocate and populate the internal stat container, and
1396 * set up the struct device.
1398 gdev = kzalloc(sizeof(*gdev), GFP_KERNEL);
1401 gdev->dev.bus = &gpio_bus_type;
1403 chip->gpiodev = gdev;
1405 gdev->dev.parent = chip->parent;
1406 gdev->dev.of_node = chip->parent->of_node;
1409 #ifdef CONFIG_OF_GPIO
1410 /* If the gpiochip has an assigned OF node this takes precedence */
1412 gdev->dev.of_node = chip->of_node;
1414 chip->of_node = gdev->dev.of_node;
1417 gdev->id = ida_simple_get(&gpio_ida, 0, 0, GFP_KERNEL);
1422 dev_set_name(&gdev->dev, "gpiochip%d", gdev->id);
1423 device_initialize(&gdev->dev);
1424 dev_set_drvdata(&gdev->dev, gdev);
1425 if (chip->parent && chip->parent->driver)
1426 gdev->owner = chip->parent->driver->owner;
1427 else if (chip->owner)
1428 /* TODO: remove chip->owner */
1429 gdev->owner = chip->owner;
1431 gdev->owner = THIS_MODULE;
1433 gdev->descs = kcalloc(chip->ngpio, sizeof(gdev->descs[0]), GFP_KERNEL);
1439 if (chip->ngpio == 0) {
1440 chip_err(chip, "tried to insert a GPIO chip with zero lines\n");
1442 goto err_free_descs;
1445 if (chip->ngpio > FASTPATH_NGPIO)
1446 chip_warn(chip, "line cnt %u is greater than fast path cnt %u\n",
1447 chip->ngpio, FASTPATH_NGPIO);
1449 gdev->label = kstrdup_const(chip->label ?: "unknown", GFP_KERNEL);
1452 goto err_free_descs;
1455 gdev->ngpio = chip->ngpio;
1458 spin_lock_irqsave(&gpio_lock, flags);
1461 * TODO: this allocates a Linux GPIO number base in the global
1462 * GPIO numberspace for this chip. In the long run we want to
1463 * get *rid* of this numberspace and use only descriptors, but
1464 * it may be a pipe dream. It will not happen before we get rid
1465 * of the sysfs interface anyways.
1468 base = gpiochip_find_base(chip->ngpio);
1471 spin_unlock_irqrestore(&gpio_lock, flags);
1472 goto err_free_label;
1475 * TODO: it should not be necessary to reflect the assigned
1476 * base outside of the GPIO subsystem. Go over drivers and
1477 * see if anyone makes use of this, else drop this and assign
1484 ret = gpiodev_add_to_list(gdev);
1486 spin_unlock_irqrestore(&gpio_lock, flags);
1487 goto err_free_label;
1490 spin_unlock_irqrestore(&gpio_lock, flags);
1492 for (i = 0; i < chip->ngpio; i++)
1493 gdev->descs[i].gdev = gdev;
1495 #ifdef CONFIG_PINCTRL
1496 INIT_LIST_HEAD(&gdev->pin_ranges);
1499 ret = gpiochip_set_desc_names(chip);
1501 goto err_remove_from_list;
1503 ret = gpiochip_alloc_valid_mask(chip);
1505 goto err_remove_from_list;
1507 ret = of_gpiochip_add(chip);
1509 goto err_free_gpiochip_mask;
1511 ret = gpiochip_init_valid_mask(chip);
1513 goto err_remove_of_chip;
1515 for (i = 0; i < chip->ngpio; i++) {
1516 struct gpio_desc *desc = &gdev->descs[i];
1518 if (chip->get_direction && gpiochip_line_is_valid(chip, i)) {
1519 if (!chip->get_direction(chip, i))
1520 set_bit(FLAG_IS_OUT, &desc->flags);
1522 clear_bit(FLAG_IS_OUT, &desc->flags);
1524 if (!chip->direction_input)
1525 set_bit(FLAG_IS_OUT, &desc->flags);
1527 clear_bit(FLAG_IS_OUT, &desc->flags);
1531 ret = gpiochip_add_pin_ranges(chip);
1533 goto err_remove_of_chip;
1535 acpi_gpiochip_add(chip);
1537 machine_gpiochip_add(chip);
1539 ret = gpiochip_irqchip_init_valid_mask(chip);
1541 goto err_remove_acpi_chip;
1543 ret = gpiochip_irqchip_init_hw(chip);
1545 goto err_remove_acpi_chip;
1547 ret = gpiochip_add_irqchip(chip, lock_key, request_key);
1549 goto err_remove_irqchip_mask;
1552 * By first adding the chardev, and then adding the device,
1553 * we get a device node entry in sysfs under
1554 * /sys/bus/gpio/devices/gpiochipN/dev that can be used for
1555 * coldplug of device nodes and other udev business.
1556 * We can do this only if gpiolib has been initialized.
1557 * Otherwise, defer until later.
1559 if (gpiolib_initialized) {
1560 ret = gpiochip_setup_dev(gdev);
1562 goto err_remove_irqchip;
1567 gpiochip_irqchip_remove(chip);
1568 err_remove_irqchip_mask:
1569 gpiochip_irqchip_free_valid_mask(chip);
1570 err_remove_acpi_chip:
1571 acpi_gpiochip_remove(chip);
1573 gpiochip_free_hogs(chip);
1574 of_gpiochip_remove(chip);
1575 err_free_gpiochip_mask:
1576 gpiochip_remove_pin_ranges(chip);
1577 gpiochip_free_valid_mask(chip);
1578 err_remove_from_list:
1579 spin_lock_irqsave(&gpio_lock, flags);
1580 list_del(&gdev->list);
1581 spin_unlock_irqrestore(&gpio_lock, flags);
1583 kfree_const(gdev->label);
1587 ida_simple_remove(&gpio_ida, gdev->id);
1589 /* failures here can mean systems won't boot... */
1590 pr_err("%s: GPIOs %d..%d (%s) failed to register, %d\n", __func__,
1591 gdev->base, gdev->base + gdev->ngpio - 1,
1592 chip->label ? : "generic", ret);
1596 EXPORT_SYMBOL_GPL(gpiochip_add_data_with_key);
1599 * gpiochip_get_data() - get per-subdriver data for the chip
1603 * The per-subdriver data for the chip.
1605 void *gpiochip_get_data(struct gpio_chip *chip)
1607 return chip->gpiodev->data;
1609 EXPORT_SYMBOL_GPL(gpiochip_get_data);
1612 * gpiochip_remove() - unregister a gpio_chip
1613 * @chip: the chip to unregister
1615 * A gpio_chip with any GPIOs still requested may not be removed.
1617 void gpiochip_remove(struct gpio_chip *chip)
1619 struct gpio_device *gdev = chip->gpiodev;
1620 struct gpio_desc *desc;
1621 unsigned long flags;
1623 bool requested = false;
1625 /* FIXME: should the legacy sysfs handling be moved to gpio_device? */
1626 gpiochip_sysfs_unregister(gdev);
1627 gpiochip_free_hogs(chip);
1628 /* Numb the device, cancelling all outstanding operations */
1630 gpiochip_irqchip_remove(chip);
1631 acpi_gpiochip_remove(chip);
1632 of_gpiochip_remove(chip);
1633 gpiochip_remove_pin_ranges(chip);
1634 gpiochip_free_valid_mask(chip);
1636 * We accept no more calls into the driver from this point, so
1637 * NULL the driver data pointer
1641 spin_lock_irqsave(&gpio_lock, flags);
1642 for (i = 0; i < gdev->ngpio; i++) {
1643 desc = &gdev->descs[i];
1644 if (test_bit(FLAG_REQUESTED, &desc->flags))
1647 spin_unlock_irqrestore(&gpio_lock, flags);
1650 dev_crit(&gdev->dev,
1651 "REMOVING GPIOCHIP WITH GPIOS STILL REQUESTED\n");
1654 * The gpiochip side puts its use of the device to rest here:
1655 * if there are no userspace clients, the chardev and device will
1656 * be removed, else it will be dangling until the last user is
1659 cdev_device_del(&gdev->chrdev, &gdev->dev);
1660 put_device(&gdev->dev);
1662 EXPORT_SYMBOL_GPL(gpiochip_remove);
1664 static void devm_gpio_chip_release(struct device *dev, void *res)
1666 struct gpio_chip *chip = *(struct gpio_chip **)res;
1668 gpiochip_remove(chip);
1672 * devm_gpiochip_add_data() - Resource manager gpiochip_add_data()
1673 * @dev: pointer to the device that gpio_chip belongs to.
1674 * @chip: the chip to register, with chip->base initialized
1675 * @data: driver-private data associated with this chip
1677 * Context: potentially before irqs will work
1679 * The gpio chip automatically be released when the device is unbound.
1682 * A negative errno if the chip can't be registered, such as because the
1683 * chip->base is invalid or already associated with a different chip.
1684 * Otherwise it returns zero as a success code.
1686 int devm_gpiochip_add_data(struct device *dev, struct gpio_chip *chip,
1689 struct gpio_chip **ptr;
1692 ptr = devres_alloc(devm_gpio_chip_release, sizeof(*ptr),
1697 ret = gpiochip_add_data(chip, data);
1704 devres_add(dev, ptr);
1708 EXPORT_SYMBOL_GPL(devm_gpiochip_add_data);
1711 * gpiochip_find() - iterator for locating a specific gpio_chip
1712 * @data: data to pass to match function
1713 * @match: Callback function to check gpio_chip
1715 * Similar to bus_find_device. It returns a reference to a gpio_chip as
1716 * determined by a user supplied @match callback. The callback should return
1717 * 0 if the device doesn't match and non-zero if it does. If the callback is
1718 * non-zero, this function will return to the caller and not iterate over any
1721 struct gpio_chip *gpiochip_find(void *data,
1722 int (*match)(struct gpio_chip *chip,
1725 struct gpio_device *gdev;
1726 struct gpio_chip *chip = NULL;
1727 unsigned long flags;
1729 spin_lock_irqsave(&gpio_lock, flags);
1730 list_for_each_entry(gdev, &gpio_devices, list)
1731 if (gdev->chip && match(gdev->chip, data)) {
1736 spin_unlock_irqrestore(&gpio_lock, flags);
1740 EXPORT_SYMBOL_GPL(gpiochip_find);
1742 static int gpiochip_match_name(struct gpio_chip *chip, void *data)
1744 const char *name = data;
1746 return !strcmp(chip->label, name);
1749 static struct gpio_chip *find_chip_by_name(const char *name)
1751 return gpiochip_find((void *)name, gpiochip_match_name);
1754 #ifdef CONFIG_GPIOLIB_IRQCHIP
1757 * The following is irqchip helper code for gpiochips.
1760 static int gpiochip_irqchip_init_hw(struct gpio_chip *gc)
1762 struct gpio_irq_chip *girq = &gc->irq;
1767 return girq->init_hw(gc);
1770 static int gpiochip_irqchip_init_valid_mask(struct gpio_chip *gc)
1772 struct gpio_irq_chip *girq = &gc->irq;
1774 if (!girq->init_valid_mask)
1777 girq->valid_mask = gpiochip_allocate_mask(gc);
1778 if (!girq->valid_mask)
1781 girq->init_valid_mask(gc, girq->valid_mask, gc->ngpio);
1786 static void gpiochip_irqchip_free_valid_mask(struct gpio_chip *gpiochip)
1788 bitmap_free(gpiochip->irq.valid_mask);
1789 gpiochip->irq.valid_mask = NULL;
1792 bool gpiochip_irqchip_irq_valid(const struct gpio_chip *gpiochip,
1793 unsigned int offset)
1795 if (!gpiochip_line_is_valid(gpiochip, offset))
1797 /* No mask means all valid */
1798 if (likely(!gpiochip->irq.valid_mask))
1800 return test_bit(offset, gpiochip->irq.valid_mask);
1802 EXPORT_SYMBOL_GPL(gpiochip_irqchip_irq_valid);
1805 * gpiochip_set_cascaded_irqchip() - connects a cascaded irqchip to a gpiochip
1806 * @gc: the gpiochip to set the irqchip chain to
1807 * @parent_irq: the irq number corresponding to the parent IRQ for this
1809 * @parent_handler: the parent interrupt handler for the accumulated IRQ
1810 * coming out of the gpiochip. If the interrupt is nested rather than
1811 * cascaded, pass NULL in this handler argument
1813 static void gpiochip_set_cascaded_irqchip(struct gpio_chip *gc,
1814 unsigned int parent_irq,
1815 irq_flow_handler_t parent_handler)
1817 struct gpio_irq_chip *girq = &gc->irq;
1818 struct device *dev = &gc->gpiodev->dev;
1820 if (!girq->domain) {
1821 chip_err(gc, "called %s before setting up irqchip\n",
1826 if (parent_handler) {
1827 if (gc->can_sleep) {
1829 "you cannot have chained interrupts on a chip that may sleep\n");
1832 girq->parents = devm_kcalloc(dev, 1,
1833 sizeof(*girq->parents),
1835 if (!girq->parents) {
1836 chip_err(gc, "out of memory allocating parent IRQ\n");
1839 girq->parents[0] = parent_irq;
1840 girq->num_parents = 1;
1842 * The parent irqchip is already using the chip_data for this
1843 * irqchip, so our callbacks simply use the handler_data.
1845 irq_set_chained_handler_and_data(parent_irq, parent_handler,
1851 * gpiochip_set_chained_irqchip() - connects a chained irqchip to a gpiochip
1852 * @gpiochip: the gpiochip to set the irqchip chain to
1853 * @irqchip: the irqchip to chain to the gpiochip
1854 * @parent_irq: the irq number corresponding to the parent IRQ for this
1856 * @parent_handler: the parent interrupt handler for the accumulated IRQ
1857 * coming out of the gpiochip.
1859 void gpiochip_set_chained_irqchip(struct gpio_chip *gpiochip,
1860 struct irq_chip *irqchip,
1861 unsigned int parent_irq,
1862 irq_flow_handler_t parent_handler)
1864 if (gpiochip->irq.threaded) {
1865 chip_err(gpiochip, "tried to chain a threaded gpiochip\n");
1869 gpiochip_set_cascaded_irqchip(gpiochip, parent_irq, parent_handler);
1871 EXPORT_SYMBOL_GPL(gpiochip_set_chained_irqchip);
1874 * gpiochip_set_nested_irqchip() - connects a nested irqchip to a gpiochip
1875 * @gpiochip: the gpiochip to set the irqchip nested handler to
1876 * @irqchip: the irqchip to nest to the gpiochip
1877 * @parent_irq: the irq number corresponding to the parent IRQ for this
1880 void gpiochip_set_nested_irqchip(struct gpio_chip *gpiochip,
1881 struct irq_chip *irqchip,
1882 unsigned int parent_irq)
1884 gpiochip_set_cascaded_irqchip(gpiochip, parent_irq, NULL);
1886 EXPORT_SYMBOL_GPL(gpiochip_set_nested_irqchip);
1888 #ifdef CONFIG_IRQ_DOMAIN_HIERARCHY
1891 * gpiochip_set_hierarchical_irqchip() - connects a hierarchical irqchip
1893 * @gc: the gpiochip to set the irqchip hierarchical handler to
1894 * @irqchip: the irqchip to handle this level of the hierarchy, the interrupt
1895 * will then percolate up to the parent
1897 static void gpiochip_set_hierarchical_irqchip(struct gpio_chip *gc,
1898 struct irq_chip *irqchip)
1900 /* DT will deal with mapping each IRQ as we go along */
1901 if (is_of_node(gc->irq.fwnode))
1905 * This is for legacy and boardfile "irqchip" fwnodes: allocate
1906 * irqs upfront instead of dynamically since we don't have the
1907 * dynamic type of allocation that hardware description languages
1908 * provide. Once all GPIO drivers using board files are gone from
1909 * the kernel we can delete this code, but for a transitional period
1910 * it is necessary to keep this around.
1912 if (is_fwnode_irqchip(gc->irq.fwnode)) {
1916 for (i = 0; i < gc->ngpio; i++) {
1917 struct irq_fwspec fwspec;
1918 unsigned int parent_hwirq;
1919 unsigned int parent_type;
1920 struct gpio_irq_chip *girq = &gc->irq;
1923 * We call the child to parent translation function
1924 * only to check if the child IRQ is valid or not.
1925 * Just pick the rising edge type here as that is what
1926 * we likely need to support.
1928 ret = girq->child_to_parent_hwirq(gc, i,
1929 IRQ_TYPE_EDGE_RISING,
1933 chip_err(gc, "skip set-up on hwirq %d\n",
1938 fwspec.fwnode = gc->irq.fwnode;
1939 /* This is the hwirq for the GPIO line side of things */
1940 fwspec.param[0] = girq->child_offset_to_irq(gc, i);
1941 /* Just pick something */
1942 fwspec.param[1] = IRQ_TYPE_EDGE_RISING;
1943 fwspec.param_count = 2;
1944 ret = __irq_domain_alloc_irqs(gc->irq.domain,
1945 /* just pick something */
1954 "can not allocate irq for GPIO line %d parent hwirq %d in hierarchy domain: %d\n",
1961 chip_err(gc, "%s unknown fwnode type proceed anyway\n", __func__);
1966 static int gpiochip_hierarchy_irq_domain_translate(struct irq_domain *d,
1967 struct irq_fwspec *fwspec,
1968 unsigned long *hwirq,
1971 /* We support standard DT translation */
1972 if (is_of_node(fwspec->fwnode) && fwspec->param_count == 2) {
1973 return irq_domain_translate_twocell(d, fwspec, hwirq, type);
1976 /* This is for board files and others not using DT */
1977 if (is_fwnode_irqchip(fwspec->fwnode)) {
1980 ret = irq_domain_translate_twocell(d, fwspec, hwirq, type);
1983 WARN_ON(*type == IRQ_TYPE_NONE);
1989 static int gpiochip_hierarchy_irq_domain_alloc(struct irq_domain *d,
1991 unsigned int nr_irqs,
1994 struct gpio_chip *gc = d->host_data;
1995 irq_hw_number_t hwirq;
1996 unsigned int type = IRQ_TYPE_NONE;
1997 struct irq_fwspec *fwspec = data;
1998 struct irq_fwspec parent_fwspec;
1999 unsigned int parent_hwirq;
2000 unsigned int parent_type;
2001 struct gpio_irq_chip *girq = &gc->irq;
2005 * The nr_irqs parameter is always one except for PCI multi-MSI
2006 * so this should not happen.
2008 WARN_ON(nr_irqs != 1);
2010 ret = gc->irq.child_irq_domain_ops.translate(d, fwspec, &hwirq, &type);
2014 chip_info(gc, "allocate IRQ %d, hwirq %lu\n", irq, hwirq);
2016 ret = girq->child_to_parent_hwirq(gc, hwirq, type,
2017 &parent_hwirq, &parent_type);
2019 chip_err(gc, "can't look up hwirq %lu\n", hwirq);
2022 chip_info(gc, "found parent hwirq %u\n", parent_hwirq);
2025 * We set handle_bad_irq because the .set_type() should
2026 * always be invoked and set the right type of handler.
2028 irq_domain_set_info(d,
2038 * Create a IRQ fwspec to send up to the parent irqdomain:
2039 * specify the hwirq we address on the parent and tie it
2040 * all together up the chain.
2042 parent_fwspec.fwnode = d->parent->fwnode;
2043 /* This parent only handles asserted level IRQs */
2044 girq->populate_parent_fwspec(gc, &parent_fwspec, parent_hwirq,
2046 chip_info(gc, "alloc_irqs_parent for %d parent hwirq %d\n",
2048 ret = irq_domain_alloc_irqs_parent(d, irq, 1, &parent_fwspec);
2051 "failed to allocate parent hwirq %d for hwirq %lu\n",
2052 parent_hwirq, hwirq);
2057 static unsigned int gpiochip_child_offset_to_irq_noop(struct gpio_chip *chip,
2058 unsigned int offset)
2063 static void gpiochip_hierarchy_setup_domain_ops(struct irq_domain_ops *ops)
2065 ops->activate = gpiochip_irq_domain_activate;
2066 ops->deactivate = gpiochip_irq_domain_deactivate;
2067 ops->alloc = gpiochip_hierarchy_irq_domain_alloc;
2068 ops->free = irq_domain_free_irqs_common;
2071 * We only allow overriding the translate() function for
2072 * hierarchical chips, and this should only be done if the user
2073 * really need something other than 1:1 translation.
2075 if (!ops->translate)
2076 ops->translate = gpiochip_hierarchy_irq_domain_translate;
2079 static int gpiochip_hierarchy_add_domain(struct gpio_chip *gc)
2081 if (!gc->irq.child_to_parent_hwirq ||
2083 chip_err(gc, "missing irqdomain vital data\n");
2087 if (!gc->irq.child_offset_to_irq)
2088 gc->irq.child_offset_to_irq = gpiochip_child_offset_to_irq_noop;
2090 if (!gc->irq.populate_parent_fwspec)
2091 gc->irq.populate_parent_fwspec =
2092 gpiochip_populate_parent_fwspec_twocell;
2094 gpiochip_hierarchy_setup_domain_ops(&gc->irq.child_irq_domain_ops);
2096 gc->irq.domain = irq_domain_create_hierarchy(
2097 gc->irq.parent_domain,
2101 &gc->irq.child_irq_domain_ops,
2104 if (!gc->irq.domain)
2107 gpiochip_set_hierarchical_irqchip(gc, gc->irq.chip);
2112 static bool gpiochip_hierarchy_is_hierarchical(struct gpio_chip *gc)
2114 return !!gc->irq.parent_domain;
2117 void gpiochip_populate_parent_fwspec_twocell(struct gpio_chip *chip,
2118 struct irq_fwspec *fwspec,
2119 unsigned int parent_hwirq,
2120 unsigned int parent_type)
2122 fwspec->param_count = 2;
2123 fwspec->param[0] = parent_hwirq;
2124 fwspec->param[1] = parent_type;
2126 EXPORT_SYMBOL_GPL(gpiochip_populate_parent_fwspec_twocell);
2128 void gpiochip_populate_parent_fwspec_fourcell(struct gpio_chip *chip,
2129 struct irq_fwspec *fwspec,
2130 unsigned int parent_hwirq,
2131 unsigned int parent_type)
2133 fwspec->param_count = 4;
2134 fwspec->param[0] = 0;
2135 fwspec->param[1] = parent_hwirq;
2136 fwspec->param[2] = 0;
2137 fwspec->param[3] = parent_type;
2139 EXPORT_SYMBOL_GPL(gpiochip_populate_parent_fwspec_fourcell);
2143 static int gpiochip_hierarchy_add_domain(struct gpio_chip *gc)
2148 static bool gpiochip_hierarchy_is_hierarchical(struct gpio_chip *gc)
2153 #endif /* CONFIG_IRQ_DOMAIN_HIERARCHY */
2156 * gpiochip_irq_map() - maps an IRQ into a GPIO irqchip
2157 * @d: the irqdomain used by this irqchip
2158 * @irq: the global irq number used by this GPIO irqchip irq
2159 * @hwirq: the local IRQ/GPIO line offset on this gpiochip
2161 * This function will set up the mapping for a certain IRQ line on a
2162 * gpiochip by assigning the gpiochip as chip data, and using the irqchip
2163 * stored inside the gpiochip.
2165 int gpiochip_irq_map(struct irq_domain *d, unsigned int irq,
2166 irq_hw_number_t hwirq)
2168 struct gpio_chip *chip = d->host_data;
2171 if (!gpiochip_irqchip_irq_valid(chip, hwirq))
2174 irq_set_chip_data(irq, chip);
2176 * This lock class tells lockdep that GPIO irqs are in a different
2177 * category than their parents, so it won't report false recursion.
2179 irq_set_lockdep_class(irq, chip->irq.lock_key, chip->irq.request_key);
2180 irq_set_chip_and_handler(irq, chip->irq.chip, chip->irq.handler);
2181 /* Chips that use nested thread handlers have them marked */
2182 if (chip->irq.threaded)
2183 irq_set_nested_thread(irq, 1);
2184 irq_set_noprobe(irq);
2186 if (chip->irq.num_parents == 1)
2187 ret = irq_set_parent(irq, chip->irq.parents[0]);
2188 else if (chip->irq.map)
2189 ret = irq_set_parent(irq, chip->irq.map[hwirq]);
2195 * No set-up of the hardware will happen if IRQ_TYPE_NONE
2196 * is passed as default type.
2198 if (chip->irq.default_type != IRQ_TYPE_NONE)
2199 irq_set_irq_type(irq, chip->irq.default_type);
2203 EXPORT_SYMBOL_GPL(gpiochip_irq_map);
2205 void gpiochip_irq_unmap(struct irq_domain *d, unsigned int irq)
2207 struct gpio_chip *chip = d->host_data;
2209 if (chip->irq.threaded)
2210 irq_set_nested_thread(irq, 0);
2211 irq_set_chip_and_handler(irq, NULL, NULL);
2212 irq_set_chip_data(irq, NULL);
2214 EXPORT_SYMBOL_GPL(gpiochip_irq_unmap);
2216 static const struct irq_domain_ops gpiochip_domain_ops = {
2217 .map = gpiochip_irq_map,
2218 .unmap = gpiochip_irq_unmap,
2219 /* Virtually all GPIO irqchips are twocell:ed */
2220 .xlate = irq_domain_xlate_twocell,
2224 * TODO: move these activate/deactivate in under the hierarchicial
2225 * irqchip implementation as static once SPMI and SSBI (all external
2226 * users) are phased over.
2229 * gpiochip_irq_domain_activate() - Lock a GPIO to be used as an IRQ
2230 * @domain: The IRQ domain used by this IRQ chip
2231 * @data: Outermost irq_data associated with the IRQ
2232 * @reserve: If set, only reserve an interrupt vector instead of assigning one
2234 * This function is a wrapper that calls gpiochip_lock_as_irq() and is to be
2235 * used as the activate function for the &struct irq_domain_ops. The host_data
2236 * for the IRQ domain must be the &struct gpio_chip.
2238 int gpiochip_irq_domain_activate(struct irq_domain *domain,
2239 struct irq_data *data, bool reserve)
2241 struct gpio_chip *chip = domain->host_data;
2243 return gpiochip_lock_as_irq(chip, data->hwirq);
2245 EXPORT_SYMBOL_GPL(gpiochip_irq_domain_activate);
2248 * gpiochip_irq_domain_deactivate() - Unlock a GPIO used as an IRQ
2249 * @domain: The IRQ domain used by this IRQ chip
2250 * @data: Outermost irq_data associated with the IRQ
2252 * This function is a wrapper that will call gpiochip_unlock_as_irq() and is to
2253 * be used as the deactivate function for the &struct irq_domain_ops. The
2254 * host_data for the IRQ domain must be the &struct gpio_chip.
2256 void gpiochip_irq_domain_deactivate(struct irq_domain *domain,
2257 struct irq_data *data)
2259 struct gpio_chip *chip = domain->host_data;
2261 return gpiochip_unlock_as_irq(chip, data->hwirq);
2263 EXPORT_SYMBOL_GPL(gpiochip_irq_domain_deactivate);
2265 static int gpiochip_to_irq(struct gpio_chip *chip, unsigned offset)
2267 struct irq_domain *domain = chip->irq.domain;
2269 if (!gpiochip_irqchip_irq_valid(chip, offset))
2272 #ifdef CONFIG_IRQ_DOMAIN_HIERARCHY
2273 if (irq_domain_is_hierarchy(domain)) {
2274 struct irq_fwspec spec;
2276 spec.fwnode = domain->fwnode;
2277 spec.param_count = 2;
2278 spec.param[0] = chip->irq.child_offset_to_irq(chip, offset);
2279 spec.param[1] = IRQ_TYPE_NONE;
2281 return irq_create_fwspec_mapping(&spec);
2285 return irq_create_mapping(domain, offset);
2288 static int gpiochip_irq_reqres(struct irq_data *d)
2290 struct gpio_chip *chip = irq_data_get_irq_chip_data(d);
2292 return gpiochip_reqres_irq(chip, d->hwirq);
2295 static void gpiochip_irq_relres(struct irq_data *d)
2297 struct gpio_chip *chip = irq_data_get_irq_chip_data(d);
2299 gpiochip_relres_irq(chip, d->hwirq);
2302 static void gpiochip_irq_enable(struct irq_data *d)
2304 struct gpio_chip *chip = irq_data_get_irq_chip_data(d);
2306 gpiochip_enable_irq(chip, d->hwirq);
2307 if (chip->irq.irq_enable)
2308 chip->irq.irq_enable(d);
2310 chip->irq.chip->irq_unmask(d);
2313 static void gpiochip_irq_disable(struct irq_data *d)
2315 struct gpio_chip *chip = irq_data_get_irq_chip_data(d);
2317 if (chip->irq.irq_disable)
2318 chip->irq.irq_disable(d);
2320 chip->irq.chip->irq_mask(d);
2321 gpiochip_disable_irq(chip, d->hwirq);
2324 static void gpiochip_set_irq_hooks(struct gpio_chip *gpiochip)
2326 struct irq_chip *irqchip = gpiochip->irq.chip;
2328 if (!irqchip->irq_request_resources &&
2329 !irqchip->irq_release_resources) {
2330 irqchip->irq_request_resources = gpiochip_irq_reqres;
2331 irqchip->irq_release_resources = gpiochip_irq_relres;
2333 if (WARN_ON(gpiochip->irq.irq_enable))
2335 /* Check if the irqchip already has this hook... */
2336 if (irqchip->irq_enable == gpiochip_irq_enable) {
2338 * ...and if so, give a gentle warning that this is bad
2342 "detected irqchip that is shared with multiple gpiochips: please fix the driver.\n");
2345 gpiochip->irq.irq_enable = irqchip->irq_enable;
2346 gpiochip->irq.irq_disable = irqchip->irq_disable;
2347 irqchip->irq_enable = gpiochip_irq_enable;
2348 irqchip->irq_disable = gpiochip_irq_disable;
2352 * gpiochip_add_irqchip() - adds an IRQ chip to a GPIO chip
2353 * @gpiochip: the GPIO chip to add the IRQ chip to
2354 * @lock_key: lockdep class for IRQ lock
2355 * @request_key: lockdep class for IRQ request
2357 static int gpiochip_add_irqchip(struct gpio_chip *gpiochip,
2358 struct lock_class_key *lock_key,
2359 struct lock_class_key *request_key)
2361 struct irq_chip *irqchip = gpiochip->irq.chip;
2362 const struct irq_domain_ops *ops = NULL;
2363 struct device_node *np;
2370 if (gpiochip->irq.parent_handler && gpiochip->can_sleep) {
2371 chip_err(gpiochip, "you cannot have chained interrupts on a chip that may sleep\n");
2375 np = gpiochip->gpiodev->dev.of_node;
2376 type = gpiochip->irq.default_type;
2379 * Specifying a default trigger is a terrible idea if DT or ACPI is
2380 * used to configure the interrupts, as you may end up with
2381 * conflicting triggers. Tell the user, and reset to NONE.
2383 if (WARN(np && type != IRQ_TYPE_NONE,
2384 "%s: Ignoring %u default trigger\n", np->full_name, type))
2385 type = IRQ_TYPE_NONE;
2387 if (has_acpi_companion(gpiochip->parent) && type != IRQ_TYPE_NONE) {
2388 acpi_handle_warn(ACPI_HANDLE(gpiochip->parent),
2389 "Ignoring %u default trigger\n", type);
2390 type = IRQ_TYPE_NONE;
2393 gpiochip->to_irq = gpiochip_to_irq;
2394 gpiochip->irq.default_type = type;
2395 gpiochip->irq.lock_key = lock_key;
2396 gpiochip->irq.request_key = request_key;
2398 /* If a parent irqdomain is provided, let's build a hierarchy */
2399 if (gpiochip_hierarchy_is_hierarchical(gpiochip)) {
2400 int ret = gpiochip_hierarchy_add_domain(gpiochip);
2404 /* Some drivers provide custom irqdomain ops */
2405 if (gpiochip->irq.domain_ops)
2406 ops = gpiochip->irq.domain_ops;
2409 ops = &gpiochip_domain_ops;
2410 gpiochip->irq.domain = irq_domain_add_simple(np,
2412 gpiochip->irq.first,
2414 if (!gpiochip->irq.domain)
2418 if (gpiochip->irq.parent_handler) {
2419 void *data = gpiochip->irq.parent_handler_data ?: gpiochip;
2421 for (i = 0; i < gpiochip->irq.num_parents; i++) {
2423 * The parent IRQ chip is already using the chip_data
2424 * for this IRQ chip, so our callbacks simply use the
2427 irq_set_chained_handler_and_data(gpiochip->irq.parents[i],
2428 gpiochip->irq.parent_handler,
2433 gpiochip_set_irq_hooks(gpiochip);
2435 acpi_gpiochip_request_interrupts(gpiochip);
2441 * gpiochip_irqchip_remove() - removes an irqchip added to a gpiochip
2442 * @gpiochip: the gpiochip to remove the irqchip from
2444 * This is called only from gpiochip_remove()
2446 static void gpiochip_irqchip_remove(struct gpio_chip *gpiochip)
2448 struct irq_chip *irqchip = gpiochip->irq.chip;
2449 unsigned int offset;
2451 acpi_gpiochip_free_interrupts(gpiochip);
2453 if (irqchip && gpiochip->irq.parent_handler) {
2454 struct gpio_irq_chip *irq = &gpiochip->irq;
2457 for (i = 0; i < irq->num_parents; i++)
2458 irq_set_chained_handler_and_data(irq->parents[i],
2462 /* Remove all IRQ mappings and delete the domain */
2463 if (gpiochip->irq.domain) {
2466 for (offset = 0; offset < gpiochip->ngpio; offset++) {
2467 if (!gpiochip_irqchip_irq_valid(gpiochip, offset))
2470 irq = irq_find_mapping(gpiochip->irq.domain, offset);
2471 irq_dispose_mapping(irq);
2474 irq_domain_remove(gpiochip->irq.domain);
2478 if (irqchip->irq_request_resources == gpiochip_irq_reqres) {
2479 irqchip->irq_request_resources = NULL;
2480 irqchip->irq_release_resources = NULL;
2482 if (irqchip->irq_enable == gpiochip_irq_enable) {
2483 irqchip->irq_enable = gpiochip->irq.irq_enable;
2484 irqchip->irq_disable = gpiochip->irq.irq_disable;
2487 gpiochip->irq.irq_enable = NULL;
2488 gpiochip->irq.irq_disable = NULL;
2489 gpiochip->irq.chip = NULL;
2491 gpiochip_irqchip_free_valid_mask(gpiochip);
2495 * gpiochip_irqchip_add_key() - adds an irqchip to a gpiochip
2496 * @gpiochip: the gpiochip to add the irqchip to
2497 * @irqchip: the irqchip to add to the gpiochip
2498 * @first_irq: if not dynamically assigned, the base (first) IRQ to
2499 * allocate gpiochip irqs from
2500 * @handler: the irq handler to use (often a predefined irq core function)
2501 * @type: the default type for IRQs on this irqchip, pass IRQ_TYPE_NONE
2502 * to have the core avoid setting up any default type in the hardware.
2503 * @threaded: whether this irqchip uses a nested thread handler
2504 * @lock_key: lockdep class for IRQ lock
2505 * @request_key: lockdep class for IRQ request
2507 * This function closely associates a certain irqchip with a certain
2508 * gpiochip, providing an irq domain to translate the local IRQs to
2509 * global irqs in the gpiolib core, and making sure that the gpiochip
2510 * is passed as chip data to all related functions. Driver callbacks
2511 * need to use gpiochip_get_data() to get their local state containers back
2512 * from the gpiochip passed as chip data. An irqdomain will be stored
2513 * in the gpiochip that shall be used by the driver to handle IRQ number
2514 * translation. The gpiochip will need to be initialized and registered
2515 * before calling this function.
2517 * This function will handle two cell:ed simple IRQs and assumes all
2518 * the pins on the gpiochip can generate a unique IRQ. Everything else
2519 * need to be open coded.
2521 int gpiochip_irqchip_add_key(struct gpio_chip *gpiochip,
2522 struct irq_chip *irqchip,
2523 unsigned int first_irq,
2524 irq_flow_handler_t handler,
2527 struct lock_class_key *lock_key,
2528 struct lock_class_key *request_key)
2530 struct device_node *of_node;
2532 if (!gpiochip || !irqchip)
2535 if (!gpiochip->parent) {
2536 pr_err("missing gpiochip .dev parent pointer\n");
2539 gpiochip->irq.threaded = threaded;
2540 of_node = gpiochip->parent->of_node;
2541 #ifdef CONFIG_OF_GPIO
2543 * If the gpiochip has an assigned OF node this takes precedence
2544 * FIXME: get rid of this and use gpiochip->parent->of_node
2547 if (gpiochip->of_node)
2548 of_node = gpiochip->of_node;
2551 * Specifying a default trigger is a terrible idea if DT or ACPI is
2552 * used to configure the interrupts, as you may end-up with
2553 * conflicting triggers. Tell the user, and reset to NONE.
2555 if (WARN(of_node && type != IRQ_TYPE_NONE,
2556 "%pOF: Ignoring %d default trigger\n", of_node, type))
2557 type = IRQ_TYPE_NONE;
2558 if (has_acpi_companion(gpiochip->parent) && type != IRQ_TYPE_NONE) {
2559 acpi_handle_warn(ACPI_HANDLE(gpiochip->parent),
2560 "Ignoring %d default trigger\n", type);
2561 type = IRQ_TYPE_NONE;
2564 gpiochip->irq.chip = irqchip;
2565 gpiochip->irq.handler = handler;
2566 gpiochip->irq.default_type = type;
2567 gpiochip->to_irq = gpiochip_to_irq;
2568 gpiochip->irq.lock_key = lock_key;
2569 gpiochip->irq.request_key = request_key;
2570 gpiochip->irq.domain = irq_domain_add_simple(of_node,
2571 gpiochip->ngpio, first_irq,
2572 &gpiochip_domain_ops, gpiochip);
2573 if (!gpiochip->irq.domain) {
2574 gpiochip->irq.chip = NULL;
2578 gpiochip_set_irq_hooks(gpiochip);
2580 acpi_gpiochip_request_interrupts(gpiochip);
2584 EXPORT_SYMBOL_GPL(gpiochip_irqchip_add_key);
2586 #else /* CONFIG_GPIOLIB_IRQCHIP */
2588 static inline int gpiochip_add_irqchip(struct gpio_chip *gpiochip,
2589 struct lock_class_key *lock_key,
2590 struct lock_class_key *request_key)
2594 static void gpiochip_irqchip_remove(struct gpio_chip *gpiochip) {}
2596 static inline int gpiochip_irqchip_init_hw(struct gpio_chip *gpiochip)
2601 static inline int gpiochip_irqchip_init_valid_mask(struct gpio_chip *gpiochip)
2605 static inline void gpiochip_irqchip_free_valid_mask(struct gpio_chip *gpiochip)
2608 #endif /* CONFIG_GPIOLIB_IRQCHIP */
2611 * gpiochip_generic_request() - request the gpio function for a pin
2612 * @chip: the gpiochip owning the GPIO
2613 * @offset: the offset of the GPIO to request for GPIO function
2615 int gpiochip_generic_request(struct gpio_chip *chip, unsigned offset)
2617 return pinctrl_gpio_request(chip->gpiodev->base + offset);
2619 EXPORT_SYMBOL_GPL(gpiochip_generic_request);
2622 * gpiochip_generic_free() - free the gpio function from a pin
2623 * @chip: the gpiochip to request the gpio function for
2624 * @offset: the offset of the GPIO to free from GPIO function
2626 void gpiochip_generic_free(struct gpio_chip *chip, unsigned offset)
2628 pinctrl_gpio_free(chip->gpiodev->base + offset);
2630 EXPORT_SYMBOL_GPL(gpiochip_generic_free);
2633 * gpiochip_generic_config() - apply configuration for a pin
2634 * @chip: the gpiochip owning the GPIO
2635 * @offset: the offset of the GPIO to apply the configuration
2636 * @config: the configuration to be applied
2638 int gpiochip_generic_config(struct gpio_chip *chip, unsigned offset,
2639 unsigned long config)
2641 return pinctrl_gpio_set_config(chip->gpiodev->base + offset, config);
2643 EXPORT_SYMBOL_GPL(gpiochip_generic_config);
2645 #ifdef CONFIG_PINCTRL
2648 * gpiochip_add_pingroup_range() - add a range for GPIO <-> pin mapping
2649 * @chip: the gpiochip to add the range for
2650 * @pctldev: the pin controller to map to
2651 * @gpio_offset: the start offset in the current gpio_chip number space
2652 * @pin_group: name of the pin group inside the pin controller
2654 * Calling this function directly from a DeviceTree-supported
2655 * pinctrl driver is DEPRECATED. Please see Section 2.1 of
2656 * Documentation/devicetree/bindings/gpio/gpio.txt on how to
2657 * bind pinctrl and gpio drivers via the "gpio-ranges" property.
2659 int gpiochip_add_pingroup_range(struct gpio_chip *chip,
2660 struct pinctrl_dev *pctldev,
2661 unsigned int gpio_offset, const char *pin_group)
2663 struct gpio_pin_range *pin_range;
2664 struct gpio_device *gdev = chip->gpiodev;
2667 pin_range = kzalloc(sizeof(*pin_range), GFP_KERNEL);
2669 chip_err(chip, "failed to allocate pin ranges\n");
2673 /* Use local offset as range ID */
2674 pin_range->range.id = gpio_offset;
2675 pin_range->range.gc = chip;
2676 pin_range->range.name = chip->label;
2677 pin_range->range.base = gdev->base + gpio_offset;
2678 pin_range->pctldev = pctldev;
2680 ret = pinctrl_get_group_pins(pctldev, pin_group,
2681 &pin_range->range.pins,
2682 &pin_range->range.npins);
2688 pinctrl_add_gpio_range(pctldev, &pin_range->range);
2690 chip_dbg(chip, "created GPIO range %d->%d ==> %s PINGRP %s\n",
2691 gpio_offset, gpio_offset + pin_range->range.npins - 1,
2692 pinctrl_dev_get_devname(pctldev), pin_group);
2694 list_add_tail(&pin_range->node, &gdev->pin_ranges);
2698 EXPORT_SYMBOL_GPL(gpiochip_add_pingroup_range);
2701 * gpiochip_add_pin_range() - add a range for GPIO <-> pin mapping
2702 * @chip: the gpiochip to add the range for
2703 * @pinctl_name: the dev_name() of the pin controller to map to
2704 * @gpio_offset: the start offset in the current gpio_chip number space
2705 * @pin_offset: the start offset in the pin controller number space
2706 * @npins: the number of pins from the offset of each pin space (GPIO and
2707 * pin controller) to accumulate in this range
2710 * 0 on success, or a negative error-code on failure.
2712 * Calling this function directly from a DeviceTree-supported
2713 * pinctrl driver is DEPRECATED. Please see Section 2.1 of
2714 * Documentation/devicetree/bindings/gpio/gpio.txt on how to
2715 * bind pinctrl and gpio drivers via the "gpio-ranges" property.
2717 int gpiochip_add_pin_range(struct gpio_chip *chip, const char *pinctl_name,
2718 unsigned int gpio_offset, unsigned int pin_offset,
2721 struct gpio_pin_range *pin_range;
2722 struct gpio_device *gdev = chip->gpiodev;
2725 pin_range = kzalloc(sizeof(*pin_range), GFP_KERNEL);
2727 chip_err(chip, "failed to allocate pin ranges\n");
2731 /* Use local offset as range ID */
2732 pin_range->range.id = gpio_offset;
2733 pin_range->range.gc = chip;
2734 pin_range->range.name = chip->label;
2735 pin_range->range.base = gdev->base + gpio_offset;
2736 pin_range->range.pin_base = pin_offset;
2737 pin_range->range.npins = npins;
2738 pin_range->pctldev = pinctrl_find_and_add_gpio_range(pinctl_name,
2740 if (IS_ERR(pin_range->pctldev)) {
2741 ret = PTR_ERR(pin_range->pctldev);
2742 chip_err(chip, "could not create pin range\n");
2746 chip_dbg(chip, "created GPIO range %d->%d ==> %s PIN %d->%d\n",
2747 gpio_offset, gpio_offset + npins - 1,
2749 pin_offset, pin_offset + npins - 1);
2751 list_add_tail(&pin_range->node, &gdev->pin_ranges);
2755 EXPORT_SYMBOL_GPL(gpiochip_add_pin_range);
2758 * gpiochip_remove_pin_ranges() - remove all the GPIO <-> pin mappings
2759 * @chip: the chip to remove all the mappings for
2761 void gpiochip_remove_pin_ranges(struct gpio_chip *chip)
2763 struct gpio_pin_range *pin_range, *tmp;
2764 struct gpio_device *gdev = chip->gpiodev;
2766 list_for_each_entry_safe(pin_range, tmp, &gdev->pin_ranges, node) {
2767 list_del(&pin_range->node);
2768 pinctrl_remove_gpio_range(pin_range->pctldev,
2773 EXPORT_SYMBOL_GPL(gpiochip_remove_pin_ranges);
2775 #endif /* CONFIG_PINCTRL */
2777 /* These "optional" allocation calls help prevent drivers from stomping
2778 * on each other, and help provide better diagnostics in debugfs.
2779 * They're called even less than the "set direction" calls.
2781 static int gpiod_request_commit(struct gpio_desc *desc, const char *label)
2783 struct gpio_chip *chip = desc->gdev->chip;
2785 unsigned long flags;
2789 label = kstrdup_const(label, GFP_KERNEL);
2794 spin_lock_irqsave(&gpio_lock, flags);
2796 /* NOTE: gpio_request() can be called in early boot,
2797 * before IRQs are enabled, for non-sleeping (SOC) GPIOs.
2800 if (test_and_set_bit(FLAG_REQUESTED, &desc->flags) == 0) {
2801 desc_set_label(desc, label ? : "?");
2809 if (chip->request) {
2810 /* chip->request may sleep */
2811 spin_unlock_irqrestore(&gpio_lock, flags);
2812 offset = gpio_chip_hwgpio(desc);
2813 if (gpiochip_line_is_valid(chip, offset))
2814 ret = chip->request(chip, offset);
2817 spin_lock_irqsave(&gpio_lock, flags);
2820 desc_set_label(desc, NULL);
2822 clear_bit(FLAG_REQUESTED, &desc->flags);
2826 if (chip->get_direction) {
2827 /* chip->get_direction may sleep */
2828 spin_unlock_irqrestore(&gpio_lock, flags);
2829 gpiod_get_direction(desc);
2830 spin_lock_irqsave(&gpio_lock, flags);
2833 spin_unlock_irqrestore(&gpio_lock, flags);
2838 * This descriptor validation needs to be inserted verbatim into each
2839 * function taking a descriptor, so we need to use a preprocessor
2840 * macro to avoid endless duplication. If the desc is NULL it is an
2841 * optional GPIO and calls should just bail out.
2843 static int validate_desc(const struct gpio_desc *desc, const char *func)
2848 pr_warn("%s: invalid GPIO (errorpointer)\n", func);
2849 return PTR_ERR(desc);
2852 pr_warn("%s: invalid GPIO (no device)\n", func);
2855 if (!desc->gdev->chip) {
2856 dev_warn(&desc->gdev->dev,
2857 "%s: backing chip is gone\n", func);
2863 #define VALIDATE_DESC(desc) do { \
2864 int __valid = validate_desc(desc, __func__); \
2869 #define VALIDATE_DESC_VOID(desc) do { \
2870 int __valid = validate_desc(desc, __func__); \
2875 int gpiod_request(struct gpio_desc *desc, const char *label)
2877 int ret = -EPROBE_DEFER;
2878 struct gpio_device *gdev;
2880 VALIDATE_DESC(desc);
2883 if (try_module_get(gdev->owner)) {
2884 ret = gpiod_request_commit(desc, label);
2886 module_put(gdev->owner);
2888 get_device(&gdev->dev);
2892 gpiod_dbg(desc, "%s: status %d\n", __func__, ret);
2897 static bool gpiod_free_commit(struct gpio_desc *desc)
2900 unsigned long flags;
2901 struct gpio_chip *chip;
2905 gpiod_unexport(desc);
2907 spin_lock_irqsave(&gpio_lock, flags);
2909 chip = desc->gdev->chip;
2910 if (chip && test_bit(FLAG_REQUESTED, &desc->flags)) {
2912 spin_unlock_irqrestore(&gpio_lock, flags);
2913 might_sleep_if(chip->can_sleep);
2914 chip->free(chip, gpio_chip_hwgpio(desc));
2915 spin_lock_irqsave(&gpio_lock, flags);
2917 kfree_const(desc->label);
2918 desc_set_label(desc, NULL);
2919 clear_bit(FLAG_ACTIVE_LOW, &desc->flags);
2920 clear_bit(FLAG_REQUESTED, &desc->flags);
2921 clear_bit(FLAG_OPEN_DRAIN, &desc->flags);
2922 clear_bit(FLAG_OPEN_SOURCE, &desc->flags);
2923 clear_bit(FLAG_PULL_UP, &desc->flags);
2924 clear_bit(FLAG_PULL_DOWN, &desc->flags);
2925 clear_bit(FLAG_BIAS_DISABLE, &desc->flags);
2926 clear_bit(FLAG_IS_HOGGED, &desc->flags);
2930 spin_unlock_irqrestore(&gpio_lock, flags);
2934 void gpiod_free(struct gpio_desc *desc)
2936 if (desc && desc->gdev && gpiod_free_commit(desc)) {
2937 module_put(desc->gdev->owner);
2938 put_device(&desc->gdev->dev);
2940 WARN_ON(extra_checks);
2945 * gpiochip_is_requested - return string iff signal was requested
2946 * @chip: controller managing the signal
2947 * @offset: of signal within controller's 0..(ngpio - 1) range
2949 * Returns NULL if the GPIO is not currently requested, else a string.
2950 * The string returned is the label passed to gpio_request(); if none has been
2951 * passed it is a meaningless, non-NULL constant.
2953 * This function is for use by GPIO controller drivers. The label can
2954 * help with diagnostics, and knowing that the signal is used as a GPIO
2955 * can help avoid accidentally multiplexing it to another controller.
2957 const char *gpiochip_is_requested(struct gpio_chip *chip, unsigned offset)
2959 struct gpio_desc *desc;
2961 if (offset >= chip->ngpio)
2964 desc = &chip->gpiodev->descs[offset];
2966 if (test_bit(FLAG_REQUESTED, &desc->flags) == 0)
2970 EXPORT_SYMBOL_GPL(gpiochip_is_requested);
2973 * gpiochip_request_own_desc - Allow GPIO chip to request its own descriptor
2975 * @hwnum: hardware number of the GPIO for which to request the descriptor
2976 * @label: label for the GPIO
2977 * @lflags: lookup flags for this GPIO or 0 if default, this can be used to
2978 * specify things like line inversion semantics with the machine flags
2979 * such as GPIO_OUT_LOW
2980 * @dflags: descriptor request flags for this GPIO or 0 if default, this
2981 * can be used to specify consumer semantics such as open drain
2983 * Function allows GPIO chip drivers to request and use their own GPIO
2984 * descriptors via gpiolib API. Difference to gpiod_request() is that this
2985 * function will not increase reference count of the GPIO chip module. This
2986 * allows the GPIO chip module to be unloaded as needed (we assume that the
2987 * GPIO chip driver handles freeing the GPIOs it has requested).
2990 * A pointer to the GPIO descriptor, or an ERR_PTR()-encoded negative error
2993 struct gpio_desc *gpiochip_request_own_desc(struct gpio_chip *chip, u16 hwnum,
2995 enum gpio_lookup_flags lflags,
2996 enum gpiod_flags dflags)
2998 struct gpio_desc *desc = gpiochip_get_desc(chip, hwnum);
3002 chip_err(chip, "failed to get GPIO descriptor\n");
3006 ret = gpiod_request_commit(desc, label);
3008 return ERR_PTR(ret);
3010 ret = gpiod_configure_flags(desc, label, lflags, dflags);
3012 chip_err(chip, "setup of own GPIO %s failed\n", label);
3013 gpiod_free_commit(desc);
3014 return ERR_PTR(ret);
3019 EXPORT_SYMBOL_GPL(gpiochip_request_own_desc);
3022 * gpiochip_free_own_desc - Free GPIO requested by the chip driver
3023 * @desc: GPIO descriptor to free
3025 * Function frees the given GPIO requested previously with
3026 * gpiochip_request_own_desc().
3028 void gpiochip_free_own_desc(struct gpio_desc *desc)
3031 gpiod_free_commit(desc);
3033 EXPORT_SYMBOL_GPL(gpiochip_free_own_desc);
3036 * Drivers MUST set GPIO direction before making get/set calls. In
3037 * some cases this is done in early boot, before IRQs are enabled.
3039 * As a rule these aren't called more than once (except for drivers
3040 * using the open-drain emulation idiom) so these are natural places
3041 * to accumulate extra debugging checks. Note that we can't (yet)
3042 * rely on gpio_request() having been called beforehand.
3045 static int gpio_set_config(struct gpio_chip *gc, unsigned offset,
3046 enum pin_config_param mode)
3048 unsigned long config;
3052 case PIN_CONFIG_BIAS_DISABLE:
3053 case PIN_CONFIG_BIAS_PULL_DOWN:
3054 case PIN_CONFIG_BIAS_PULL_UP:
3062 config = PIN_CONF_PACKED(mode, arg);
3063 return gc->set_config ? gc->set_config(gc, offset, config) : -ENOTSUPP;
3066 static int gpio_set_bias(struct gpio_chip *chip, struct gpio_desc *desc)
3071 if (test_bit(FLAG_BIAS_DISABLE, &desc->flags))
3072 bias = PIN_CONFIG_BIAS_DISABLE;
3073 else if (test_bit(FLAG_PULL_UP, &desc->flags))
3074 bias = PIN_CONFIG_BIAS_PULL_UP;
3075 else if (test_bit(FLAG_PULL_DOWN, &desc->flags))
3076 bias = PIN_CONFIG_BIAS_PULL_DOWN;
3079 ret = gpio_set_config(chip, gpio_chip_hwgpio(desc), bias);
3080 if (ret != -ENOTSUPP)
3087 * gpiod_direction_input - set the GPIO direction to input
3088 * @desc: GPIO to set to input
3090 * Set the direction of the passed GPIO to input, such as gpiod_get_value() can
3091 * be called safely on it.
3093 * Return 0 in case of success, else an error code.
3095 int gpiod_direction_input(struct gpio_desc *desc)
3097 struct gpio_chip *chip;
3100 VALIDATE_DESC(desc);
3101 chip = desc->gdev->chip;
3104 * It is legal to have no .get() and .direction_input() specified if
3105 * the chip is output-only, but you can't specify .direction_input()
3106 * and not support the .get() operation, that doesn't make sense.
3108 if (!chip->get && chip->direction_input) {
3110 "%s: missing get() but have direction_input()\n",
3116 * If we have a .direction_input() callback, things are simple,
3117 * just call it. Else we are some input-only chip so try to check the
3118 * direction (if .get_direction() is supported) else we silently
3119 * assume we are in input mode after this.
3121 if (chip->direction_input) {
3122 ret = chip->direction_input(chip, gpio_chip_hwgpio(desc));
3123 } else if (chip->get_direction &&
3124 (chip->get_direction(chip, gpio_chip_hwgpio(desc)) != 1)) {
3126 "%s: missing direction_input() operation and line is output\n",
3131 clear_bit(FLAG_IS_OUT, &desc->flags);
3132 ret = gpio_set_bias(chip, desc);
3135 trace_gpio_direction(desc_to_gpio(desc), 1, ret);
3139 EXPORT_SYMBOL_GPL(gpiod_direction_input);
3141 static int gpiod_direction_output_raw_commit(struct gpio_desc *desc, int value)
3143 struct gpio_chip *gc = desc->gdev->chip;
3148 * It's OK not to specify .direction_output() if the gpiochip is
3149 * output-only, but if there is then not even a .set() operation it
3150 * is pretty tricky to drive the output line.
3152 if (!gc->set && !gc->direction_output) {
3154 "%s: missing set() and direction_output() operations\n",
3159 if (gc->direction_output) {
3160 ret = gc->direction_output(gc, gpio_chip_hwgpio(desc), val);
3162 /* Check that we are in output mode if we can */
3163 if (gc->get_direction &&
3164 gc->get_direction(gc, gpio_chip_hwgpio(desc))) {
3166 "%s: missing direction_output() operation\n",
3171 * If we can't actively set the direction, we are some
3172 * output-only chip, so just drive the output as desired.
3174 gc->set(gc, gpio_chip_hwgpio(desc), val);
3178 set_bit(FLAG_IS_OUT, &desc->flags);
3179 trace_gpio_value(desc_to_gpio(desc), 0, val);
3180 trace_gpio_direction(desc_to_gpio(desc), 0, ret);
3185 * gpiod_direction_output_raw - set the GPIO direction to output
3186 * @desc: GPIO to set to output
3187 * @value: initial output value of the GPIO
3189 * Set the direction of the passed GPIO to output, such as gpiod_set_value() can
3190 * be called safely on it. The initial value of the output must be specified
3191 * as raw value on the physical line without regard for the ACTIVE_LOW status.
3193 * Return 0 in case of success, else an error code.
3195 int gpiod_direction_output_raw(struct gpio_desc *desc, int value)
3197 VALIDATE_DESC(desc);
3198 return gpiod_direction_output_raw_commit(desc, value);
3200 EXPORT_SYMBOL_GPL(gpiod_direction_output_raw);
3203 * gpiod_direction_output - set the GPIO direction to output
3204 * @desc: GPIO to set to output
3205 * @value: initial output value of the GPIO
3207 * Set the direction of the passed GPIO to output, such as gpiod_set_value() can
3208 * be called safely on it. The initial value of the output must be specified
3209 * as the logical value of the GPIO, i.e. taking its ACTIVE_LOW status into
3212 * Return 0 in case of success, else an error code.
3214 int gpiod_direction_output(struct gpio_desc *desc, int value)
3216 struct gpio_chip *gc;
3219 VALIDATE_DESC(desc);
3220 if (test_bit(FLAG_ACTIVE_LOW, &desc->flags))
3225 /* GPIOs used for enabled IRQs shall not be set as output */
3226 if (test_bit(FLAG_USED_AS_IRQ, &desc->flags) &&
3227 test_bit(FLAG_IRQ_IS_ENABLED, &desc->flags)) {
3229 "%s: tried to set a GPIO tied to an IRQ as output\n",
3234 gc = desc->gdev->chip;
3235 if (test_bit(FLAG_OPEN_DRAIN, &desc->flags)) {
3236 /* First see if we can enable open drain in hardware */
3237 ret = gpio_set_config(gc, gpio_chip_hwgpio(desc),
3238 PIN_CONFIG_DRIVE_OPEN_DRAIN);
3240 goto set_output_value;
3241 /* Emulate open drain by not actively driving the line high */
3243 ret = gpiod_direction_input(desc);
3244 goto set_output_flag;
3247 else if (test_bit(FLAG_OPEN_SOURCE, &desc->flags)) {
3248 ret = gpio_set_config(gc, gpio_chip_hwgpio(desc),
3249 PIN_CONFIG_DRIVE_OPEN_SOURCE);
3251 goto set_output_value;
3252 /* Emulate open source by not actively driving the line low */
3254 ret = gpiod_direction_input(desc);
3255 goto set_output_flag;
3258 gpio_set_config(gc, gpio_chip_hwgpio(desc),
3259 PIN_CONFIG_DRIVE_PUSH_PULL);
3263 ret = gpio_set_bias(gc, desc);
3266 return gpiod_direction_output_raw_commit(desc, value);
3270 * When emulating open-source or open-drain functionalities by not
3271 * actively driving the line (setting mode to input) we still need to
3272 * set the IS_OUT flag or otherwise we won't be able to set the line
3276 set_bit(FLAG_IS_OUT, &desc->flags);
3279 EXPORT_SYMBOL_GPL(gpiod_direction_output);
3282 * gpiod_set_debounce - sets @debounce time for a GPIO
3283 * @desc: descriptor of the GPIO for which to set debounce time
3284 * @debounce: debounce time in microseconds
3287 * 0 on success, %-ENOTSUPP if the controller doesn't support setting the
3290 int gpiod_set_debounce(struct gpio_desc *desc, unsigned debounce)
3292 struct gpio_chip *chip;
3293 unsigned long config;
3295 VALIDATE_DESC(desc);
3296 chip = desc->gdev->chip;
3297 if (!chip->set || !chip->set_config) {
3299 "%s: missing set() or set_config() operations\n",
3304 config = pinconf_to_config_packed(PIN_CONFIG_INPUT_DEBOUNCE, debounce);
3305 return chip->set_config(chip, gpio_chip_hwgpio(desc), config);
3307 EXPORT_SYMBOL_GPL(gpiod_set_debounce);
3310 * gpiod_set_transitory - Lose or retain GPIO state on suspend or reset
3311 * @desc: descriptor of the GPIO for which to configure persistence
3312 * @transitory: True to lose state on suspend or reset, false for persistence
3315 * 0 on success, otherwise a negative error code.
3317 int gpiod_set_transitory(struct gpio_desc *desc, bool transitory)
3319 struct gpio_chip *chip;
3320 unsigned long packed;
3324 VALIDATE_DESC(desc);
3326 * Handle FLAG_TRANSITORY first, enabling queries to gpiolib for
3327 * persistence state.
3330 set_bit(FLAG_TRANSITORY, &desc->flags);
3332 clear_bit(FLAG_TRANSITORY, &desc->flags);
3334 /* If the driver supports it, set the persistence state now */
3335 chip = desc->gdev->chip;
3336 if (!chip->set_config)
3339 packed = pinconf_to_config_packed(PIN_CONFIG_PERSIST_STATE,
3341 gpio = gpio_chip_hwgpio(desc);
3342 rc = chip->set_config(chip, gpio, packed);
3343 if (rc == -ENOTSUPP) {
3344 dev_dbg(&desc->gdev->dev, "Persistence not supported for GPIO %d\n",
3351 EXPORT_SYMBOL_GPL(gpiod_set_transitory);
3354 * gpiod_is_active_low - test whether a GPIO is active-low or not
3355 * @desc: the gpio descriptor to test
3357 * Returns 1 if the GPIO is active-low, 0 otherwise.
3359 int gpiod_is_active_low(const struct gpio_desc *desc)
3361 VALIDATE_DESC(desc);
3362 return test_bit(FLAG_ACTIVE_LOW, &desc->flags);
3364 EXPORT_SYMBOL_GPL(gpiod_is_active_low);
3366 /* I/O calls are only valid after configuration completed; the relevant
3367 * "is this a valid GPIO" error checks should already have been done.
3369 * "Get" operations are often inlinable as reading a pin value register,
3370 * and masking the relevant bit in that register.
3372 * When "set" operations are inlinable, they involve writing that mask to
3373 * one register to set a low value, or a different register to set it high.
3374 * Otherwise locking is needed, so there may be little value to inlining.
3376 *------------------------------------------------------------------------
3378 * IMPORTANT!!! The hot paths -- get/set value -- assume that callers
3379 * have requested the GPIO. That can include implicit requesting by
3380 * a direction setting call. Marking a gpio as requested locks its chip
3381 * in memory, guaranteeing that these table lookups need no more locking
3382 * and that gpiochip_remove() will fail.
3384 * REVISIT when debugging, consider adding some instrumentation to ensure
3385 * that the GPIO was actually requested.
3388 static int gpiod_get_raw_value_commit(const struct gpio_desc *desc)
3390 struct gpio_chip *chip;
3394 chip = desc->gdev->chip;
3395 offset = gpio_chip_hwgpio(desc);
3396 value = chip->get ? chip->get(chip, offset) : -EIO;
3397 value = value < 0 ? value : !!value;
3398 trace_gpio_value(desc_to_gpio(desc), 1, value);
3402 static int gpio_chip_get_multiple(struct gpio_chip *chip,
3403 unsigned long *mask, unsigned long *bits)
3405 if (chip->get_multiple) {
3406 return chip->get_multiple(chip, mask, bits);
3407 } else if (chip->get) {
3410 for_each_set_bit(i, mask, chip->ngpio) {
3411 value = chip->get(chip, i);
3414 __assign_bit(i, bits, value);
3421 int gpiod_get_array_value_complex(bool raw, bool can_sleep,
3422 unsigned int array_size,
3423 struct gpio_desc **desc_array,
3424 struct gpio_array *array_info,
3425 unsigned long *value_bitmap)
3430 * Validate array_info against desc_array and its size.
3431 * It should immediately follow desc_array if both
3432 * have been obtained from the same gpiod_get_array() call.
3434 if (array_info && array_info->desc == desc_array &&
3435 array_size <= array_info->size &&
3436 (void *)array_info == desc_array + array_info->size) {
3438 WARN_ON(array_info->chip->can_sleep);
3440 ret = gpio_chip_get_multiple(array_info->chip,
3441 array_info->get_mask,
3446 if (!raw && !bitmap_empty(array_info->invert_mask, array_size))
3447 bitmap_xor(value_bitmap, value_bitmap,
3448 array_info->invert_mask, array_size);
3450 if (bitmap_full(array_info->get_mask, array_size))
3453 i = find_first_zero_bit(array_info->get_mask, array_size);
3458 while (i < array_size) {
3459 struct gpio_chip *chip = desc_array[i]->gdev->chip;
3460 unsigned long fastpath[2 * BITS_TO_LONGS(FASTPATH_NGPIO)];
3461 unsigned long *mask, *bits;
3464 if (likely(chip->ngpio <= FASTPATH_NGPIO)) {
3467 mask = kmalloc_array(2 * BITS_TO_LONGS(chip->ngpio),
3469 can_sleep ? GFP_KERNEL : GFP_ATOMIC);
3474 bits = mask + BITS_TO_LONGS(chip->ngpio);
3475 bitmap_zero(mask, chip->ngpio);
3478 WARN_ON(chip->can_sleep);
3480 /* collect all inputs belonging to the same chip */
3483 const struct gpio_desc *desc = desc_array[i];
3484 int hwgpio = gpio_chip_hwgpio(desc);
3486 __set_bit(hwgpio, mask);
3490 i = find_next_zero_bit(array_info->get_mask,
3492 } while ((i < array_size) &&
3493 (desc_array[i]->gdev->chip == chip));
3495 ret = gpio_chip_get_multiple(chip, mask, bits);
3497 if (mask != fastpath)
3502 for (j = first; j < i; ) {
3503 const struct gpio_desc *desc = desc_array[j];
3504 int hwgpio = gpio_chip_hwgpio(desc);
3505 int value = test_bit(hwgpio, bits);
3507 if (!raw && test_bit(FLAG_ACTIVE_LOW, &desc->flags))
3509 __assign_bit(j, value_bitmap, value);
3510 trace_gpio_value(desc_to_gpio(desc), 1, value);
3514 j = find_next_zero_bit(array_info->get_mask, i,
3518 if (mask != fastpath)
3525 * gpiod_get_raw_value() - return a gpio's raw value
3526 * @desc: gpio whose value will be returned
3528 * Return the GPIO's raw value, i.e. the value of the physical line disregarding
3529 * its ACTIVE_LOW status, or negative errno on failure.
3531 * This function can be called from contexts where we cannot sleep, and will
3532 * complain if the GPIO chip functions potentially sleep.
3534 int gpiod_get_raw_value(const struct gpio_desc *desc)
3536 VALIDATE_DESC(desc);
3537 /* Should be using gpiod_get_raw_value_cansleep() */
3538 WARN_ON(desc->gdev->chip->can_sleep);
3539 return gpiod_get_raw_value_commit(desc);
3541 EXPORT_SYMBOL_GPL(gpiod_get_raw_value);
3544 * gpiod_get_value() - return a gpio's value
3545 * @desc: gpio whose value will be returned
3547 * Return the GPIO's logical value, i.e. taking the ACTIVE_LOW status into
3548 * account, or negative errno on failure.
3550 * This function can be called from contexts where we cannot sleep, and will
3551 * complain if the GPIO chip functions potentially sleep.
3553 int gpiod_get_value(const struct gpio_desc *desc)
3557 VALIDATE_DESC(desc);
3558 /* Should be using gpiod_get_value_cansleep() */
3559 WARN_ON(desc->gdev->chip->can_sleep);
3561 value = gpiod_get_raw_value_commit(desc);
3565 if (test_bit(FLAG_ACTIVE_LOW, &desc->flags))
3570 EXPORT_SYMBOL_GPL(gpiod_get_value);
3573 * gpiod_get_raw_array_value() - read raw values from an array of GPIOs
3574 * @array_size: number of elements in the descriptor array / value bitmap
3575 * @desc_array: array of GPIO descriptors whose values will be read
3576 * @array_info: information on applicability of fast bitmap processing path
3577 * @value_bitmap: bitmap to store the read values
3579 * Read the raw values of the GPIOs, i.e. the values of the physical lines
3580 * without regard for their ACTIVE_LOW status. Return 0 in case of success,
3581 * else an error code.
3583 * This function can be called from contexts where we cannot sleep,
3584 * and it will complain if the GPIO chip functions potentially sleep.
3586 int gpiod_get_raw_array_value(unsigned int array_size,
3587 struct gpio_desc **desc_array,
3588 struct gpio_array *array_info,
3589 unsigned long *value_bitmap)
3593 return gpiod_get_array_value_complex(true, false, array_size,
3594 desc_array, array_info,
3597 EXPORT_SYMBOL_GPL(gpiod_get_raw_array_value);
3600 * gpiod_get_array_value() - read values from an array of GPIOs
3601 * @array_size: number of elements in the descriptor array / value bitmap
3602 * @desc_array: array of GPIO descriptors whose values will be read
3603 * @array_info: information on applicability of fast bitmap processing path
3604 * @value_bitmap: bitmap to store the read values
3606 * Read the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status
3607 * into account. Return 0 in case of success, else an error code.
3609 * This function can be called from contexts where we cannot sleep,
3610 * and it will complain if the GPIO chip functions potentially sleep.
3612 int gpiod_get_array_value(unsigned int array_size,
3613 struct gpio_desc **desc_array,
3614 struct gpio_array *array_info,
3615 unsigned long *value_bitmap)
3619 return gpiod_get_array_value_complex(false, false, array_size,
3620 desc_array, array_info,
3623 EXPORT_SYMBOL_GPL(gpiod_get_array_value);
3626 * gpio_set_open_drain_value_commit() - Set the open drain gpio's value.
3627 * @desc: gpio descriptor whose state need to be set.
3628 * @value: Non-zero for setting it HIGH otherwise it will set to LOW.
3630 static void gpio_set_open_drain_value_commit(struct gpio_desc *desc, bool value)
3633 struct gpio_chip *chip = desc->gdev->chip;
3634 int offset = gpio_chip_hwgpio(desc);
3637 ret = chip->direction_input(chip, offset);
3639 ret = chip->direction_output(chip, offset, 0);
3641 set_bit(FLAG_IS_OUT, &desc->flags);
3643 trace_gpio_direction(desc_to_gpio(desc), value, ret);
3646 "%s: Error in set_value for open drain err %d\n",
3651 * _gpio_set_open_source_value() - Set the open source gpio's value.
3652 * @desc: gpio descriptor whose state need to be set.
3653 * @value: Non-zero for setting it HIGH otherwise it will set to LOW.
3655 static void gpio_set_open_source_value_commit(struct gpio_desc *desc, bool value)
3658 struct gpio_chip *chip = desc->gdev->chip;
3659 int offset = gpio_chip_hwgpio(desc);
3662 ret = chip->direction_output(chip, offset, 1);
3664 set_bit(FLAG_IS_OUT, &desc->flags);
3666 ret = chip->direction_input(chip, offset);
3668 trace_gpio_direction(desc_to_gpio(desc), !value, ret);
3671 "%s: Error in set_value for open source err %d\n",
3675 static void gpiod_set_raw_value_commit(struct gpio_desc *desc, bool value)
3677 struct gpio_chip *chip;
3679 chip = desc->gdev->chip;
3680 trace_gpio_value(desc_to_gpio(desc), 0, value);
3681 chip->set(chip, gpio_chip_hwgpio(desc), value);
3685 * set multiple outputs on the same chip;
3686 * use the chip's set_multiple function if available;
3687 * otherwise set the outputs sequentially;
3688 * @mask: bit mask array; one bit per output; BITS_PER_LONG bits per word
3689 * defines which outputs are to be changed
3690 * @bits: bit value array; one bit per output; BITS_PER_LONG bits per word
3691 * defines the values the outputs specified by mask are to be set to
3693 static void gpio_chip_set_multiple(struct gpio_chip *chip,
3694 unsigned long *mask, unsigned long *bits)
3696 if (chip->set_multiple) {
3697 chip->set_multiple(chip, mask, bits);
3701 /* set outputs if the corresponding mask bit is set */
3702 for_each_set_bit(i, mask, chip->ngpio)
3703 chip->set(chip, i, test_bit(i, bits));
3707 int gpiod_set_array_value_complex(bool raw, bool can_sleep,
3708 unsigned int array_size,
3709 struct gpio_desc **desc_array,
3710 struct gpio_array *array_info,
3711 unsigned long *value_bitmap)
3716 * Validate array_info against desc_array and its size.
3717 * It should immediately follow desc_array if both
3718 * have been obtained from the same gpiod_get_array() call.
3720 if (array_info && array_info->desc == desc_array &&
3721 array_size <= array_info->size &&
3722 (void *)array_info == desc_array + array_info->size) {
3724 WARN_ON(array_info->chip->can_sleep);
3726 if (!raw && !bitmap_empty(array_info->invert_mask, array_size))
3727 bitmap_xor(value_bitmap, value_bitmap,
3728 array_info->invert_mask, array_size);
3730 gpio_chip_set_multiple(array_info->chip, array_info->set_mask,
3733 if (bitmap_full(array_info->set_mask, array_size))
3736 i = find_first_zero_bit(array_info->set_mask, array_size);
3741 while (i < array_size) {
3742 struct gpio_chip *chip = desc_array[i]->gdev->chip;
3743 unsigned long fastpath[2 * BITS_TO_LONGS(FASTPATH_NGPIO)];
3744 unsigned long *mask, *bits;
3747 if (likely(chip->ngpio <= FASTPATH_NGPIO)) {
3750 mask = kmalloc_array(2 * BITS_TO_LONGS(chip->ngpio),
3752 can_sleep ? GFP_KERNEL : GFP_ATOMIC);
3757 bits = mask + BITS_TO_LONGS(chip->ngpio);
3758 bitmap_zero(mask, chip->ngpio);
3761 WARN_ON(chip->can_sleep);
3764 struct gpio_desc *desc = desc_array[i];
3765 int hwgpio = gpio_chip_hwgpio(desc);
3766 int value = test_bit(i, value_bitmap);
3769 * Pins applicable for fast input but not for
3770 * fast output processing may have been already
3771 * inverted inside the fast path, skip them.
3773 if (!raw && !(array_info &&
3774 test_bit(i, array_info->invert_mask)) &&
3775 test_bit(FLAG_ACTIVE_LOW, &desc->flags))
3777 trace_gpio_value(desc_to_gpio(desc), 0, value);
3779 * collect all normal outputs belonging to the same chip
3780 * open drain and open source outputs are set individually
3782 if (test_bit(FLAG_OPEN_DRAIN, &desc->flags) && !raw) {
3783 gpio_set_open_drain_value_commit(desc, value);
3784 } else if (test_bit(FLAG_OPEN_SOURCE, &desc->flags) && !raw) {
3785 gpio_set_open_source_value_commit(desc, value);
3787 __set_bit(hwgpio, mask);
3789 __set_bit(hwgpio, bits);
3791 __clear_bit(hwgpio, bits);
3797 i = find_next_zero_bit(array_info->set_mask,
3799 } while ((i < array_size) &&
3800 (desc_array[i]->gdev->chip == chip));
3801 /* push collected bits to outputs */
3803 gpio_chip_set_multiple(chip, mask, bits);
3805 if (mask != fastpath)
3812 * gpiod_set_raw_value() - assign a gpio's raw value
3813 * @desc: gpio whose value will be assigned
3814 * @value: value to assign
3816 * Set the raw value of the GPIO, i.e. the value of its physical line without
3817 * regard for its ACTIVE_LOW status.
3819 * This function can be called from contexts where we cannot sleep, and will
3820 * complain if the GPIO chip functions potentially sleep.
3822 void gpiod_set_raw_value(struct gpio_desc *desc, int value)
3824 VALIDATE_DESC_VOID(desc);
3825 /* Should be using gpiod_set_raw_value_cansleep() */
3826 WARN_ON(desc->gdev->chip->can_sleep);
3827 gpiod_set_raw_value_commit(desc, value);
3829 EXPORT_SYMBOL_GPL(gpiod_set_raw_value);
3832 * gpiod_set_value_nocheck() - set a GPIO line value without checking
3833 * @desc: the descriptor to set the value on
3834 * @value: value to set
3836 * This sets the value of a GPIO line backing a descriptor, applying
3837 * different semantic quirks like active low and open drain/source
3840 static void gpiod_set_value_nocheck(struct gpio_desc *desc, int value)
3842 if (test_bit(FLAG_ACTIVE_LOW, &desc->flags))
3844 if (test_bit(FLAG_OPEN_DRAIN, &desc->flags))
3845 gpio_set_open_drain_value_commit(desc, value);
3846 else if (test_bit(FLAG_OPEN_SOURCE, &desc->flags))
3847 gpio_set_open_source_value_commit(desc, value);
3849 gpiod_set_raw_value_commit(desc, value);
3853 * gpiod_set_value() - assign a gpio's value
3854 * @desc: gpio whose value will be assigned
3855 * @value: value to assign
3857 * Set the logical value of the GPIO, i.e. taking its ACTIVE_LOW,
3858 * OPEN_DRAIN and OPEN_SOURCE flags into account.
3860 * This function can be called from contexts where we cannot sleep, and will
3861 * complain if the GPIO chip functions potentially sleep.
3863 void gpiod_set_value(struct gpio_desc *desc, int value)
3865 VALIDATE_DESC_VOID(desc);
3866 /* Should be using gpiod_set_value_cansleep() */
3867 WARN_ON(desc->gdev->chip->can_sleep);
3868 gpiod_set_value_nocheck(desc, value);
3870 EXPORT_SYMBOL_GPL(gpiod_set_value);
3873 * gpiod_set_raw_array_value() - assign values to an array of GPIOs
3874 * @array_size: number of elements in the descriptor array / value bitmap
3875 * @desc_array: array of GPIO descriptors whose values will be assigned
3876 * @array_info: information on applicability of fast bitmap processing path
3877 * @value_bitmap: bitmap of values to assign
3879 * Set the raw values of the GPIOs, i.e. the values of the physical lines
3880 * without regard for their ACTIVE_LOW status.
3882 * This function can be called from contexts where we cannot sleep, and will
3883 * complain if the GPIO chip functions potentially sleep.
3885 int gpiod_set_raw_array_value(unsigned int array_size,
3886 struct gpio_desc **desc_array,
3887 struct gpio_array *array_info,
3888 unsigned long *value_bitmap)
3892 return gpiod_set_array_value_complex(true, false, array_size,
3893 desc_array, array_info, value_bitmap);
3895 EXPORT_SYMBOL_GPL(gpiod_set_raw_array_value);
3898 * gpiod_set_array_value() - assign values to an array of GPIOs
3899 * @array_size: number of elements in the descriptor array / value bitmap
3900 * @desc_array: array of GPIO descriptors whose values will be assigned
3901 * @array_info: information on applicability of fast bitmap processing path
3902 * @value_bitmap: bitmap of values to assign
3904 * Set the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status
3907 * This function can be called from contexts where we cannot sleep, and will
3908 * complain if the GPIO chip functions potentially sleep.
3910 int gpiod_set_array_value(unsigned int array_size,
3911 struct gpio_desc **desc_array,
3912 struct gpio_array *array_info,
3913 unsigned long *value_bitmap)
3917 return gpiod_set_array_value_complex(false, false, array_size,
3918 desc_array, array_info,
3921 EXPORT_SYMBOL_GPL(gpiod_set_array_value);
3924 * gpiod_cansleep() - report whether gpio value access may sleep
3925 * @desc: gpio to check
3928 int gpiod_cansleep(const struct gpio_desc *desc)
3930 VALIDATE_DESC(desc);
3931 return desc->gdev->chip->can_sleep;
3933 EXPORT_SYMBOL_GPL(gpiod_cansleep);
3936 * gpiod_set_consumer_name() - set the consumer name for the descriptor
3937 * @desc: gpio to set the consumer name on
3938 * @name: the new consumer name
3940 int gpiod_set_consumer_name(struct gpio_desc *desc, const char *name)
3942 VALIDATE_DESC(desc);
3944 name = kstrdup_const(name, GFP_KERNEL);
3949 kfree_const(desc->label);
3950 desc_set_label(desc, name);
3954 EXPORT_SYMBOL_GPL(gpiod_set_consumer_name);
3957 * gpiod_to_irq() - return the IRQ corresponding to a GPIO
3958 * @desc: gpio whose IRQ will be returned (already requested)
3960 * Return the IRQ corresponding to the passed GPIO, or an error code in case of
3963 int gpiod_to_irq(const struct gpio_desc *desc)
3965 struct gpio_chip *chip;
3969 * Cannot VALIDATE_DESC() here as gpiod_to_irq() consumer semantics
3970 * requires this function to not return zero on an invalid descriptor
3971 * but rather a negative error number.
3973 if (!desc || IS_ERR(desc) || !desc->gdev || !desc->gdev->chip)
3976 chip = desc->gdev->chip;
3977 offset = gpio_chip_hwgpio(desc);
3979 int retirq = chip->to_irq(chip, offset);
3981 /* Zero means NO_IRQ */
3989 EXPORT_SYMBOL_GPL(gpiod_to_irq);
3992 * gpiochip_lock_as_irq() - lock a GPIO to be used as IRQ
3993 * @chip: the chip the GPIO to lock belongs to
3994 * @offset: the offset of the GPIO to lock as IRQ
3996 * This is used directly by GPIO drivers that want to lock down
3997 * a certain GPIO line to be used for IRQs.
3999 int gpiochip_lock_as_irq(struct gpio_chip *chip, unsigned int offset)
4001 struct gpio_desc *desc;
4003 desc = gpiochip_get_desc(chip, offset);
4005 return PTR_ERR(desc);
4008 * If it's fast: flush the direction setting if something changed
4011 if (!chip->can_sleep && chip->get_direction) {
4012 int dir = gpiod_get_direction(desc);
4015 chip_err(chip, "%s: cannot get GPIO direction\n",
4021 if (test_bit(FLAG_IS_OUT, &desc->flags)) {
4023 "%s: tried to flag a GPIO set as output for IRQ\n",
4028 set_bit(FLAG_USED_AS_IRQ, &desc->flags);
4029 set_bit(FLAG_IRQ_IS_ENABLED, &desc->flags);
4032 * If the consumer has not set up a label (such as when the
4033 * IRQ is referenced from .to_irq()) we set up a label here
4034 * so it is clear this is used as an interrupt.
4037 desc_set_label(desc, "interrupt");
4041 EXPORT_SYMBOL_GPL(gpiochip_lock_as_irq);
4044 * gpiochip_unlock_as_irq() - unlock a GPIO used as IRQ
4045 * @chip: the chip the GPIO to lock belongs to
4046 * @offset: the offset of the GPIO to lock as IRQ
4048 * This is used directly by GPIO drivers that want to indicate
4049 * that a certain GPIO is no longer used exclusively for IRQ.
4051 void gpiochip_unlock_as_irq(struct gpio_chip *chip, unsigned int offset)
4053 struct gpio_desc *desc;
4055 desc = gpiochip_get_desc(chip, offset);
4059 clear_bit(FLAG_USED_AS_IRQ, &desc->flags);
4060 clear_bit(FLAG_IRQ_IS_ENABLED, &desc->flags);
4062 /* If we only had this marking, erase it */
4063 if (desc->label && !strcmp(desc->label, "interrupt"))
4064 desc_set_label(desc, NULL);
4066 EXPORT_SYMBOL_GPL(gpiochip_unlock_as_irq);
4068 void gpiochip_disable_irq(struct gpio_chip *chip, unsigned int offset)
4070 struct gpio_desc *desc = gpiochip_get_desc(chip, offset);
4072 if (!IS_ERR(desc) &&
4073 !WARN_ON(!test_bit(FLAG_USED_AS_IRQ, &desc->flags)))
4074 clear_bit(FLAG_IRQ_IS_ENABLED, &desc->flags);
4076 EXPORT_SYMBOL_GPL(gpiochip_disable_irq);
4078 void gpiochip_enable_irq(struct gpio_chip *chip, unsigned int offset)
4080 struct gpio_desc *desc = gpiochip_get_desc(chip, offset);
4082 if (!IS_ERR(desc) &&
4083 !WARN_ON(!test_bit(FLAG_USED_AS_IRQ, &desc->flags))) {
4084 WARN_ON(test_bit(FLAG_IS_OUT, &desc->flags));
4085 set_bit(FLAG_IRQ_IS_ENABLED, &desc->flags);
4088 EXPORT_SYMBOL_GPL(gpiochip_enable_irq);
4090 bool gpiochip_line_is_irq(struct gpio_chip *chip, unsigned int offset)
4092 if (offset >= chip->ngpio)
4095 return test_bit(FLAG_USED_AS_IRQ, &chip->gpiodev->descs[offset].flags);
4097 EXPORT_SYMBOL_GPL(gpiochip_line_is_irq);
4099 int gpiochip_reqres_irq(struct gpio_chip *chip, unsigned int offset)
4103 if (!try_module_get(chip->gpiodev->owner))
4106 ret = gpiochip_lock_as_irq(chip, offset);
4108 chip_err(chip, "unable to lock HW IRQ %u for IRQ\n", offset);
4109 module_put(chip->gpiodev->owner);
4114 EXPORT_SYMBOL_GPL(gpiochip_reqres_irq);
4116 void gpiochip_relres_irq(struct gpio_chip *chip, unsigned int offset)
4118 gpiochip_unlock_as_irq(chip, offset);
4119 module_put(chip->gpiodev->owner);
4121 EXPORT_SYMBOL_GPL(gpiochip_relres_irq);
4123 bool gpiochip_line_is_open_drain(struct gpio_chip *chip, unsigned int offset)
4125 if (offset >= chip->ngpio)
4128 return test_bit(FLAG_OPEN_DRAIN, &chip->gpiodev->descs[offset].flags);
4130 EXPORT_SYMBOL_GPL(gpiochip_line_is_open_drain);
4132 bool gpiochip_line_is_open_source(struct gpio_chip *chip, unsigned int offset)
4134 if (offset >= chip->ngpio)
4137 return test_bit(FLAG_OPEN_SOURCE, &chip->gpiodev->descs[offset].flags);
4139 EXPORT_SYMBOL_GPL(gpiochip_line_is_open_source);
4141 bool gpiochip_line_is_persistent(struct gpio_chip *chip, unsigned int offset)
4143 if (offset >= chip->ngpio)
4146 return !test_bit(FLAG_TRANSITORY, &chip->gpiodev->descs[offset].flags);
4148 EXPORT_SYMBOL_GPL(gpiochip_line_is_persistent);
4151 * gpiod_get_raw_value_cansleep() - return a gpio's raw value
4152 * @desc: gpio whose value will be returned
4154 * Return the GPIO's raw value, i.e. the value of the physical line disregarding
4155 * its ACTIVE_LOW status, or negative errno on failure.
4157 * This function is to be called from contexts that can sleep.
4159 int gpiod_get_raw_value_cansleep(const struct gpio_desc *desc)
4161 might_sleep_if(extra_checks);
4162 VALIDATE_DESC(desc);
4163 return gpiod_get_raw_value_commit(desc);
4165 EXPORT_SYMBOL_GPL(gpiod_get_raw_value_cansleep);
4168 * gpiod_get_value_cansleep() - return a gpio's value
4169 * @desc: gpio whose value will be returned
4171 * Return the GPIO's logical value, i.e. taking the ACTIVE_LOW status into
4172 * account, or negative errno on failure.
4174 * This function is to be called from contexts that can sleep.
4176 int gpiod_get_value_cansleep(const struct gpio_desc *desc)
4180 might_sleep_if(extra_checks);
4181 VALIDATE_DESC(desc);
4182 value = gpiod_get_raw_value_commit(desc);
4186 if (test_bit(FLAG_ACTIVE_LOW, &desc->flags))
4191 EXPORT_SYMBOL_GPL(gpiod_get_value_cansleep);
4194 * gpiod_get_raw_array_value_cansleep() - read raw values from an array of GPIOs
4195 * @array_size: number of elements in the descriptor array / value bitmap
4196 * @desc_array: array of GPIO descriptors whose values will be read
4197 * @array_info: information on applicability of fast bitmap processing path
4198 * @value_bitmap: bitmap to store the read values
4200 * Read the raw values of the GPIOs, i.e. the values of the physical lines
4201 * without regard for their ACTIVE_LOW status. Return 0 in case of success,
4202 * else an error code.
4204 * This function is to be called from contexts that can sleep.
4206 int gpiod_get_raw_array_value_cansleep(unsigned int array_size,
4207 struct gpio_desc **desc_array,
4208 struct gpio_array *array_info,
4209 unsigned long *value_bitmap)
4211 might_sleep_if(extra_checks);
4214 return gpiod_get_array_value_complex(true, true, array_size,
4215 desc_array, array_info,
4218 EXPORT_SYMBOL_GPL(gpiod_get_raw_array_value_cansleep);
4221 * gpiod_get_array_value_cansleep() - read values from an array of GPIOs
4222 * @array_size: number of elements in the descriptor array / value bitmap
4223 * @desc_array: array of GPIO descriptors whose values will be read
4224 * @array_info: information on applicability of fast bitmap processing path
4225 * @value_bitmap: bitmap to store the read values
4227 * Read the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status
4228 * into account. Return 0 in case of success, else an error code.
4230 * This function is to be called from contexts that can sleep.
4232 int gpiod_get_array_value_cansleep(unsigned int array_size,
4233 struct gpio_desc **desc_array,
4234 struct gpio_array *array_info,
4235 unsigned long *value_bitmap)
4237 might_sleep_if(extra_checks);
4240 return gpiod_get_array_value_complex(false, true, array_size,
4241 desc_array, array_info,
4244 EXPORT_SYMBOL_GPL(gpiod_get_array_value_cansleep);
4247 * gpiod_set_raw_value_cansleep() - assign a gpio's raw value
4248 * @desc: gpio whose value will be assigned
4249 * @value: value to assign
4251 * Set the raw value of the GPIO, i.e. the value of its physical line without
4252 * regard for its ACTIVE_LOW status.
4254 * This function is to be called from contexts that can sleep.
4256 void gpiod_set_raw_value_cansleep(struct gpio_desc *desc, int value)
4258 might_sleep_if(extra_checks);
4259 VALIDATE_DESC_VOID(desc);
4260 gpiod_set_raw_value_commit(desc, value);
4262 EXPORT_SYMBOL_GPL(gpiod_set_raw_value_cansleep);
4265 * gpiod_set_value_cansleep() - assign a gpio's value
4266 * @desc: gpio whose value will be assigned
4267 * @value: value to assign
4269 * Set the logical value of the GPIO, i.e. taking its ACTIVE_LOW status into
4272 * This function is to be called from contexts that can sleep.
4274 void gpiod_set_value_cansleep(struct gpio_desc *desc, int value)
4276 might_sleep_if(extra_checks);
4277 VALIDATE_DESC_VOID(desc);
4278 gpiod_set_value_nocheck(desc, value);
4280 EXPORT_SYMBOL_GPL(gpiod_set_value_cansleep);
4283 * gpiod_set_raw_array_value_cansleep() - assign values to an array of GPIOs
4284 * @array_size: number of elements in the descriptor array / value bitmap
4285 * @desc_array: array of GPIO descriptors whose values will be assigned
4286 * @array_info: information on applicability of fast bitmap processing path
4287 * @value_bitmap: bitmap of values to assign
4289 * Set the raw values of the GPIOs, i.e. the values of the physical lines
4290 * without regard for their ACTIVE_LOW status.
4292 * This function is to be called from contexts that can sleep.
4294 int gpiod_set_raw_array_value_cansleep(unsigned int array_size,
4295 struct gpio_desc **desc_array,
4296 struct gpio_array *array_info,
4297 unsigned long *value_bitmap)
4299 might_sleep_if(extra_checks);
4302 return gpiod_set_array_value_complex(true, true, array_size, desc_array,
4303 array_info, value_bitmap);
4305 EXPORT_SYMBOL_GPL(gpiod_set_raw_array_value_cansleep);
4308 * gpiod_add_lookup_tables() - register GPIO device consumers
4309 * @tables: list of tables of consumers to register
4310 * @n: number of tables in the list
4312 void gpiod_add_lookup_tables(struct gpiod_lookup_table **tables, size_t n)
4316 mutex_lock(&gpio_lookup_lock);
4318 for (i = 0; i < n; i++)
4319 list_add_tail(&tables[i]->list, &gpio_lookup_list);
4321 mutex_unlock(&gpio_lookup_lock);
4325 * gpiod_set_array_value_cansleep() - assign values to an array of GPIOs
4326 * @array_size: number of elements in the descriptor array / value bitmap
4327 * @desc_array: array of GPIO descriptors whose values will be assigned
4328 * @array_info: information on applicability of fast bitmap processing path
4329 * @value_bitmap: bitmap of values to assign
4331 * Set the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status
4334 * This function is to be called from contexts that can sleep.
4336 int gpiod_set_array_value_cansleep(unsigned int array_size,
4337 struct gpio_desc **desc_array,
4338 struct gpio_array *array_info,
4339 unsigned long *value_bitmap)
4341 might_sleep_if(extra_checks);
4344 return gpiod_set_array_value_complex(false, true, array_size,
4345 desc_array, array_info,
4348 EXPORT_SYMBOL_GPL(gpiod_set_array_value_cansleep);
4351 * gpiod_add_lookup_table() - register GPIO device consumers
4352 * @table: table of consumers to register
4354 void gpiod_add_lookup_table(struct gpiod_lookup_table *table)
4356 mutex_lock(&gpio_lookup_lock);
4358 list_add_tail(&table->list, &gpio_lookup_list);
4360 mutex_unlock(&gpio_lookup_lock);
4362 EXPORT_SYMBOL_GPL(gpiod_add_lookup_table);
4365 * gpiod_remove_lookup_table() - unregister GPIO device consumers
4366 * @table: table of consumers to unregister
4368 void gpiod_remove_lookup_table(struct gpiod_lookup_table *table)
4370 mutex_lock(&gpio_lookup_lock);
4372 list_del(&table->list);
4374 mutex_unlock(&gpio_lookup_lock);
4376 EXPORT_SYMBOL_GPL(gpiod_remove_lookup_table);
4379 * gpiod_add_hogs() - register a set of GPIO hogs from machine code
4380 * @hogs: table of gpio hog entries with a zeroed sentinel at the end
4382 void gpiod_add_hogs(struct gpiod_hog *hogs)
4384 struct gpio_chip *chip;
4385 struct gpiod_hog *hog;
4387 mutex_lock(&gpio_machine_hogs_mutex);
4389 for (hog = &hogs[0]; hog->chip_label; hog++) {
4390 list_add_tail(&hog->list, &gpio_machine_hogs);
4393 * The chip may have been registered earlier, so check if it
4394 * exists and, if so, try to hog the line now.
4396 chip = find_chip_by_name(hog->chip_label);
4398 gpiochip_machine_hog(chip, hog);
4401 mutex_unlock(&gpio_machine_hogs_mutex);
4403 EXPORT_SYMBOL_GPL(gpiod_add_hogs);
4405 static struct gpiod_lookup_table *gpiod_find_lookup_table(struct device *dev)
4407 const char *dev_id = dev ? dev_name(dev) : NULL;
4408 struct gpiod_lookup_table *table;
4410 mutex_lock(&gpio_lookup_lock);
4412 list_for_each_entry(table, &gpio_lookup_list, list) {
4413 if (table->dev_id && dev_id) {
4415 * Valid strings on both ends, must be identical to have
4418 if (!strcmp(table->dev_id, dev_id))
4422 * One of the pointers is NULL, so both must be to have
4425 if (dev_id == table->dev_id)
4432 mutex_unlock(&gpio_lookup_lock);
4436 static struct gpio_desc *gpiod_find(struct device *dev, const char *con_id,
4437 unsigned int idx, unsigned long *flags)
4439 struct gpio_desc *desc = ERR_PTR(-ENOENT);
4440 struct gpiod_lookup_table *table;
4441 struct gpiod_lookup *p;
4443 table = gpiod_find_lookup_table(dev);
4447 for (p = &table->table[0]; p->chip_label; p++) {
4448 struct gpio_chip *chip;
4450 /* idx must always match exactly */
4454 /* If the lookup entry has a con_id, require exact match */
4455 if (p->con_id && (!con_id || strcmp(p->con_id, con_id)))
4458 chip = find_chip_by_name(p->chip_label);
4462 * As the lookup table indicates a chip with
4463 * p->chip_label should exist, assume it may
4464 * still appear later and let the interested
4465 * consumer be probed again or let the Deferred
4466 * Probe infrastructure handle the error.
4468 dev_warn(dev, "cannot find GPIO chip %s, deferring\n",
4470 return ERR_PTR(-EPROBE_DEFER);
4473 if (chip->ngpio <= p->chip_hwnum) {
4475 "requested GPIO %d is out of range [0..%d] for chip %s\n",
4476 idx, chip->ngpio, chip->label);
4477 return ERR_PTR(-EINVAL);
4480 desc = gpiochip_get_desc(chip, p->chip_hwnum);
4489 static int platform_gpio_count(struct device *dev, const char *con_id)
4491 struct gpiod_lookup_table *table;
4492 struct gpiod_lookup *p;
4493 unsigned int count = 0;
4495 table = gpiod_find_lookup_table(dev);
4499 for (p = &table->table[0]; p->chip_label; p++) {
4500 if ((con_id && p->con_id && !strcmp(con_id, p->con_id)) ||
4501 (!con_id && !p->con_id))
4511 * fwnode_gpiod_get_index - obtain a GPIO from firmware node
4512 * @fwnode: handle of the firmware node
4513 * @con_id: function within the GPIO consumer
4514 * @index: index of the GPIO to obtain for the consumer
4515 * @flags: GPIO initialization flags
4516 * @label: label to attach to the requested GPIO
4518 * This function can be used for drivers that get their configuration
4519 * from opaque firmware.
4521 * The function properly finds the corresponding GPIO using whatever is the
4522 * underlying firmware interface and then makes sure that the GPIO
4523 * descriptor is requested before it is returned to the caller.
4526 * On successful request the GPIO pin is configured in accordance with
4529 * In case of error an ERR_PTR() is returned.
4531 struct gpio_desc *fwnode_gpiod_get_index(struct fwnode_handle *fwnode,
4532 const char *con_id, int index,
4533 enum gpiod_flags flags,
4536 struct gpio_desc *desc;
4537 char prop_name[32]; /* 32 is max size of property name */
4540 for (i = 0; i < ARRAY_SIZE(gpio_suffixes); i++) {
4542 snprintf(prop_name, sizeof(prop_name), "%s-%s",
4543 con_id, gpio_suffixes[i]);
4545 snprintf(prop_name, sizeof(prop_name), "%s",
4548 desc = fwnode_get_named_gpiod(fwnode, prop_name, index, flags,
4550 if (!IS_ERR(desc) || (PTR_ERR(desc) != -ENOENT))
4556 EXPORT_SYMBOL_GPL(fwnode_gpiod_get_index);
4559 * gpiod_count - return the number of GPIOs associated with a device / function
4560 * or -ENOENT if no GPIO has been assigned to the requested function
4561 * @dev: GPIO consumer, can be NULL for system-global GPIOs
4562 * @con_id: function within the GPIO consumer
4564 int gpiod_count(struct device *dev, const char *con_id)
4566 int count = -ENOENT;
4568 if (IS_ENABLED(CONFIG_OF) && dev && dev->of_node)
4569 count = of_gpio_get_count(dev, con_id);
4570 else if (IS_ENABLED(CONFIG_ACPI) && dev && ACPI_HANDLE(dev))
4571 count = acpi_gpio_count(dev, con_id);
4574 count = platform_gpio_count(dev, con_id);
4578 EXPORT_SYMBOL_GPL(gpiod_count);
4581 * gpiod_get - obtain a GPIO for a given GPIO function
4582 * @dev: GPIO consumer, can be NULL for system-global GPIOs
4583 * @con_id: function within the GPIO consumer
4584 * @flags: optional GPIO initialization flags
4586 * Return the GPIO descriptor corresponding to the function con_id of device
4587 * dev, -ENOENT if no GPIO has been assigned to the requested function, or
4588 * another IS_ERR() code if an error occurred while trying to acquire the GPIO.
4590 struct gpio_desc *__must_check gpiod_get(struct device *dev, const char *con_id,
4591 enum gpiod_flags flags)
4593 return gpiod_get_index(dev, con_id, 0, flags);
4595 EXPORT_SYMBOL_GPL(gpiod_get);
4598 * gpiod_get_optional - obtain an optional GPIO for a given GPIO function
4599 * @dev: GPIO consumer, can be NULL for system-global GPIOs
4600 * @con_id: function within the GPIO consumer
4601 * @flags: optional GPIO initialization flags
4603 * This is equivalent to gpiod_get(), except that when no GPIO was assigned to
4604 * the requested function it will return NULL. This is convenient for drivers
4605 * that need to handle optional GPIOs.
4607 struct gpio_desc *__must_check gpiod_get_optional(struct device *dev,
4609 enum gpiod_flags flags)
4611 return gpiod_get_index_optional(dev, con_id, 0, flags);
4613 EXPORT_SYMBOL_GPL(gpiod_get_optional);
4617 * gpiod_configure_flags - helper function to configure a given GPIO
4618 * @desc: gpio whose value will be assigned
4619 * @con_id: function within the GPIO consumer
4620 * @lflags: bitmask of gpio_lookup_flags GPIO_* values - returned from
4621 * of_find_gpio() or of_get_gpio_hog()
4622 * @dflags: gpiod_flags - optional GPIO initialization flags
4624 * Return 0 on success, -ENOENT if no GPIO has been assigned to the
4625 * requested function and/or index, or another IS_ERR() code if an error
4626 * occurred while trying to acquire the GPIO.
4628 int gpiod_configure_flags(struct gpio_desc *desc, const char *con_id,
4629 unsigned long lflags, enum gpiod_flags dflags)
4633 if (lflags & GPIO_ACTIVE_LOW)
4634 set_bit(FLAG_ACTIVE_LOW, &desc->flags);
4636 if (lflags & GPIO_OPEN_DRAIN)
4637 set_bit(FLAG_OPEN_DRAIN, &desc->flags);
4638 else if (dflags & GPIOD_FLAGS_BIT_OPEN_DRAIN) {
4640 * This enforces open drain mode from the consumer side.
4641 * This is necessary for some busses like I2C, but the lookup
4642 * should *REALLY* have specified them as open drain in the
4643 * first place, so print a little warning here.
4645 set_bit(FLAG_OPEN_DRAIN, &desc->flags);
4647 "enforced open drain please flag it properly in DT/ACPI DSDT/board file\n");
4650 if (lflags & GPIO_OPEN_SOURCE)
4651 set_bit(FLAG_OPEN_SOURCE, &desc->flags);
4653 if ((lflags & GPIO_PULL_UP) && (lflags & GPIO_PULL_DOWN)) {
4655 "both pull-up and pull-down enabled, invalid configuration\n");
4659 if (lflags & GPIO_PULL_UP)
4660 set_bit(FLAG_PULL_UP, &desc->flags);
4661 else if (lflags & GPIO_PULL_DOWN)
4662 set_bit(FLAG_PULL_DOWN, &desc->flags);
4664 ret = gpiod_set_transitory(desc, (lflags & GPIO_TRANSITORY));
4668 /* No particular flag request, return here... */
4669 if (!(dflags & GPIOD_FLAGS_BIT_DIR_SET)) {
4670 pr_debug("no flags found for %s\n", con_id);
4675 if (dflags & GPIOD_FLAGS_BIT_DIR_OUT)
4676 ret = gpiod_direction_output(desc,
4677 !!(dflags & GPIOD_FLAGS_BIT_DIR_VAL));
4679 ret = gpiod_direction_input(desc);
4685 * gpiod_get_index - obtain a GPIO from a multi-index GPIO function
4686 * @dev: GPIO consumer, can be NULL for system-global GPIOs
4687 * @con_id: function within the GPIO consumer
4688 * @idx: index of the GPIO to obtain in the consumer
4689 * @flags: optional GPIO initialization flags
4691 * This variant of gpiod_get() allows to access GPIOs other than the first
4692 * defined one for functions that define several GPIOs.
4694 * Return a valid GPIO descriptor, -ENOENT if no GPIO has been assigned to the
4695 * requested function and/or index, or another IS_ERR() code if an error
4696 * occurred while trying to acquire the GPIO.
4698 struct gpio_desc *__must_check gpiod_get_index(struct device *dev,
4701 enum gpiod_flags flags)
4703 unsigned long lookupflags = GPIO_LOOKUP_FLAGS_DEFAULT;
4704 struct gpio_desc *desc = NULL;
4706 /* Maybe we have a device name, maybe not */
4707 const char *devname = dev ? dev_name(dev) : "?";
4709 dev_dbg(dev, "GPIO lookup for consumer %s\n", con_id);
4712 /* Using device tree? */
4713 if (IS_ENABLED(CONFIG_OF) && dev->of_node) {
4714 dev_dbg(dev, "using device tree for GPIO lookup\n");
4715 desc = of_find_gpio(dev, con_id, idx, &lookupflags);
4716 } else if (ACPI_COMPANION(dev)) {
4717 dev_dbg(dev, "using ACPI for GPIO lookup\n");
4718 desc = acpi_find_gpio(dev, con_id, idx, &flags, &lookupflags);
4723 * Either we are not using DT or ACPI, or their lookup did not return
4724 * a result. In that case, use platform lookup as a fallback.
4726 if (!desc || desc == ERR_PTR(-ENOENT)) {
4727 dev_dbg(dev, "using lookup tables for GPIO lookup\n");
4728 desc = gpiod_find(dev, con_id, idx, &lookupflags);
4732 dev_dbg(dev, "No GPIO consumer %s found\n", con_id);
4737 * If a connection label was passed use that, else attempt to use
4738 * the device name as label
4740 ret = gpiod_request(desc, con_id ? con_id : devname);
4742 if (ret == -EBUSY && flags & GPIOD_FLAGS_BIT_NONEXCLUSIVE) {
4744 * This happens when there are several consumers for
4745 * the same GPIO line: we just return here without
4746 * further initialization. It is a bit if a hack.
4747 * This is necessary to support fixed regulators.
4749 * FIXME: Make this more sane and safe.
4751 dev_info(dev, "nonexclusive access to GPIO for %s\n",
4752 con_id ? con_id : devname);
4755 return ERR_PTR(ret);
4759 ret = gpiod_configure_flags(desc, con_id, lookupflags, flags);
4761 dev_dbg(dev, "setup of GPIO %s failed\n", con_id);
4763 return ERR_PTR(ret);
4768 EXPORT_SYMBOL_GPL(gpiod_get_index);
4771 * fwnode_get_named_gpiod - obtain a GPIO from firmware node
4772 * @fwnode: handle of the firmware node
4773 * @propname: name of the firmware property representing the GPIO
4774 * @index: index of the GPIO to obtain for the consumer
4775 * @dflags: GPIO initialization flags
4776 * @label: label to attach to the requested GPIO
4778 * This function can be used for drivers that get their configuration
4779 * from opaque firmware.
4781 * The function properly finds the corresponding GPIO using whatever is the
4782 * underlying firmware interface and then makes sure that the GPIO
4783 * descriptor is requested before it is returned to the caller.
4786 * On successful request the GPIO pin is configured in accordance with
4789 * In case of error an ERR_PTR() is returned.
4791 struct gpio_desc *fwnode_get_named_gpiod(struct fwnode_handle *fwnode,
4792 const char *propname, int index,
4793 enum gpiod_flags dflags,
4796 unsigned long lflags = GPIO_LOOKUP_FLAGS_DEFAULT;
4797 struct gpio_desc *desc = ERR_PTR(-ENODEV);
4801 return ERR_PTR(-EINVAL);
4803 if (is_of_node(fwnode)) {
4804 desc = gpiod_get_from_of_node(to_of_node(fwnode),
4809 } else if (is_acpi_node(fwnode)) {
4810 struct acpi_gpio_info info;
4812 desc = acpi_node_get_gpiod(fwnode, propname, index, &info);
4816 acpi_gpio_update_gpiod_flags(&dflags, &info);
4817 acpi_gpio_update_gpiod_lookup_flags(&lflags, &info);
4820 /* Currently only ACPI takes this path */
4821 ret = gpiod_request(desc, label);
4823 return ERR_PTR(ret);
4825 ret = gpiod_configure_flags(desc, propname, lflags, dflags);
4828 return ERR_PTR(ret);
4833 EXPORT_SYMBOL_GPL(fwnode_get_named_gpiod);
4836 * gpiod_get_index_optional - obtain an optional GPIO from a multi-index GPIO
4838 * @dev: GPIO consumer, can be NULL for system-global GPIOs
4839 * @con_id: function within the GPIO consumer
4840 * @index: index of the GPIO to obtain in the consumer
4841 * @flags: optional GPIO initialization flags
4843 * This is equivalent to gpiod_get_index(), except that when no GPIO with the
4844 * specified index was assigned to the requested function it will return NULL.
4845 * This is convenient for drivers that need to handle optional GPIOs.
4847 struct gpio_desc *__must_check gpiod_get_index_optional(struct device *dev,
4850 enum gpiod_flags flags)
4852 struct gpio_desc *desc;
4854 desc = gpiod_get_index(dev, con_id, index, flags);
4856 if (PTR_ERR(desc) == -ENOENT)
4862 EXPORT_SYMBOL_GPL(gpiod_get_index_optional);
4865 * gpiod_hog - Hog the specified GPIO desc given the provided flags
4866 * @desc: gpio whose value will be assigned
4867 * @name: gpio line name
4868 * @lflags: bitmask of gpio_lookup_flags GPIO_* values - returned from
4869 * of_find_gpio() or of_get_gpio_hog()
4870 * @dflags: gpiod_flags - optional GPIO initialization flags
4872 int gpiod_hog(struct gpio_desc *desc, const char *name,
4873 unsigned long lflags, enum gpiod_flags dflags)
4875 struct gpio_chip *chip;
4876 struct gpio_desc *local_desc;
4880 chip = gpiod_to_chip(desc);
4881 hwnum = gpio_chip_hwgpio(desc);
4883 local_desc = gpiochip_request_own_desc(chip, hwnum, name,
4885 if (IS_ERR(local_desc)) {
4886 ret = PTR_ERR(local_desc);
4887 pr_err("requesting hog GPIO %s (chip %s, offset %d) failed, %d\n",
4888 name, chip->label, hwnum, ret);
4892 /* Mark GPIO as hogged so it can be identified and removed later */
4893 set_bit(FLAG_IS_HOGGED, &desc->flags);
4895 pr_info("GPIO line %d (%s) hogged as %s%s\n",
4896 desc_to_gpio(desc), name,
4897 (dflags&GPIOD_FLAGS_BIT_DIR_OUT) ? "output" : "input",
4898 (dflags&GPIOD_FLAGS_BIT_DIR_OUT) ?
4899 (dflags&GPIOD_FLAGS_BIT_DIR_VAL) ? "/high" : "/low":"");
4905 * gpiochip_free_hogs - Scan gpio-controller chip and release GPIO hog
4906 * @chip: gpio chip to act on
4908 static void gpiochip_free_hogs(struct gpio_chip *chip)
4912 for (id = 0; id < chip->ngpio; id++) {
4913 if (test_bit(FLAG_IS_HOGGED, &chip->gpiodev->descs[id].flags))
4914 gpiochip_free_own_desc(&chip->gpiodev->descs[id]);
4919 * gpiod_get_array - obtain multiple GPIOs from a multi-index GPIO function
4920 * @dev: GPIO consumer, can be NULL for system-global GPIOs
4921 * @con_id: function within the GPIO consumer
4922 * @flags: optional GPIO initialization flags
4924 * This function acquires all the GPIOs defined under a given function.
4926 * Return a struct gpio_descs containing an array of descriptors, -ENOENT if
4927 * no GPIO has been assigned to the requested function, or another IS_ERR()
4928 * code if an error occurred while trying to acquire the GPIOs.
4930 struct gpio_descs *__must_check gpiod_get_array(struct device *dev,
4932 enum gpiod_flags flags)
4934 struct gpio_desc *desc;
4935 struct gpio_descs *descs;
4936 struct gpio_array *array_info = NULL;
4937 struct gpio_chip *chip;
4938 int count, bitmap_size;
4940 count = gpiod_count(dev, con_id);
4942 return ERR_PTR(count);
4944 descs = kzalloc(struct_size(descs, desc, count), GFP_KERNEL);
4946 return ERR_PTR(-ENOMEM);
4948 for (descs->ndescs = 0; descs->ndescs < count; ) {
4949 desc = gpiod_get_index(dev, con_id, descs->ndescs, flags);
4951 gpiod_put_array(descs);
4952 return ERR_CAST(desc);
4955 descs->desc[descs->ndescs] = desc;
4957 chip = gpiod_to_chip(desc);
4959 * If pin hardware number of array member 0 is also 0, select
4960 * its chip as a candidate for fast bitmap processing path.
4962 if (descs->ndescs == 0 && gpio_chip_hwgpio(desc) == 0) {
4963 struct gpio_descs *array;
4965 bitmap_size = BITS_TO_LONGS(chip->ngpio > count ?
4966 chip->ngpio : count);
4968 array = kzalloc(struct_size(descs, desc, count) +
4969 struct_size(array_info, invert_mask,
4970 3 * bitmap_size), GFP_KERNEL);
4972 gpiod_put_array(descs);
4973 return ERR_PTR(-ENOMEM);
4976 memcpy(array, descs,
4977 struct_size(descs, desc, descs->ndescs + 1));
4981 array_info = (void *)(descs->desc + count);
4982 array_info->get_mask = array_info->invert_mask +
4984 array_info->set_mask = array_info->get_mask +
4987 array_info->desc = descs->desc;
4988 array_info->size = count;
4989 array_info->chip = chip;
4990 bitmap_set(array_info->get_mask, descs->ndescs,
4991 count - descs->ndescs);
4992 bitmap_set(array_info->set_mask, descs->ndescs,
4993 count - descs->ndescs);
4994 descs->info = array_info;
4996 /* Unmark array members which don't belong to the 'fast' chip */
4997 if (array_info && array_info->chip != chip) {
4998 __clear_bit(descs->ndescs, array_info->get_mask);
4999 __clear_bit(descs->ndescs, array_info->set_mask);
5002 * Detect array members which belong to the 'fast' chip
5003 * but their pins are not in hardware order.
5005 else if (array_info &&
5006 gpio_chip_hwgpio(desc) != descs->ndescs) {
5008 * Don't use fast path if all array members processed so
5009 * far belong to the same chip as this one but its pin
5010 * hardware number is different from its array index.
5012 if (bitmap_full(array_info->get_mask, descs->ndescs)) {
5015 __clear_bit(descs->ndescs,
5016 array_info->get_mask);
5017 __clear_bit(descs->ndescs,
5018 array_info->set_mask);
5020 } else if (array_info) {
5021 /* Exclude open drain or open source from fast output */
5022 if (gpiochip_line_is_open_drain(chip, descs->ndescs) ||
5023 gpiochip_line_is_open_source(chip, descs->ndescs))
5024 __clear_bit(descs->ndescs,
5025 array_info->set_mask);
5026 /* Identify 'fast' pins which require invertion */
5027 if (gpiod_is_active_low(desc))
5028 __set_bit(descs->ndescs,
5029 array_info->invert_mask);
5036 "GPIO array info: chip=%s, size=%d, get_mask=%lx, set_mask=%lx, invert_mask=%lx\n",
5037 array_info->chip->label, array_info->size,
5038 *array_info->get_mask, *array_info->set_mask,
5039 *array_info->invert_mask);
5042 EXPORT_SYMBOL_GPL(gpiod_get_array);
5045 * gpiod_get_array_optional - obtain multiple GPIOs from a multi-index GPIO
5047 * @dev: GPIO consumer, can be NULL for system-global GPIOs
5048 * @con_id: function within the GPIO consumer
5049 * @flags: optional GPIO initialization flags
5051 * This is equivalent to gpiod_get_array(), except that when no GPIO was
5052 * assigned to the requested function it will return NULL.
5054 struct gpio_descs *__must_check gpiod_get_array_optional(struct device *dev,
5056 enum gpiod_flags flags)
5058 struct gpio_descs *descs;
5060 descs = gpiod_get_array(dev, con_id, flags);
5061 if (IS_ERR(descs) && (PTR_ERR(descs) == -ENOENT))
5066 EXPORT_SYMBOL_GPL(gpiod_get_array_optional);
5069 * gpiod_put - dispose of a GPIO descriptor
5070 * @desc: GPIO descriptor to dispose of
5072 * No descriptor can be used after gpiod_put() has been called on it.
5074 void gpiod_put(struct gpio_desc *desc)
5079 EXPORT_SYMBOL_GPL(gpiod_put);
5082 * gpiod_put_array - dispose of multiple GPIO descriptors
5083 * @descs: struct gpio_descs containing an array of descriptors
5085 void gpiod_put_array(struct gpio_descs *descs)
5089 for (i = 0; i < descs->ndescs; i++)
5090 gpiod_put(descs->desc[i]);
5094 EXPORT_SYMBOL_GPL(gpiod_put_array);
5096 static int __init gpiolib_dev_init(void)
5100 /* Register GPIO sysfs bus */
5101 ret = bus_register(&gpio_bus_type);
5103 pr_err("gpiolib: could not register GPIO bus type\n");
5107 ret = alloc_chrdev_region(&gpio_devt, 0, GPIO_DEV_MAX, "gpiochip");
5109 pr_err("gpiolib: failed to allocate char dev region\n");
5110 bus_unregister(&gpio_bus_type);
5112 gpiolib_initialized = true;
5113 gpiochip_setup_devs();
5117 core_initcall(gpiolib_dev_init);
5119 #ifdef CONFIG_DEBUG_FS
5121 static void gpiolib_dbg_show(struct seq_file *s, struct gpio_device *gdev)
5124 struct gpio_chip *chip = gdev->chip;
5125 unsigned gpio = gdev->base;
5126 struct gpio_desc *gdesc = &gdev->descs[0];
5131 for (i = 0; i < gdev->ngpio; i++, gpio++, gdesc++) {
5132 if (!test_bit(FLAG_REQUESTED, &gdesc->flags)) {
5134 seq_printf(s, " gpio-%-3d (%-20.20s)\n",
5140 gpiod_get_direction(gdesc);
5141 is_out = test_bit(FLAG_IS_OUT, &gdesc->flags);
5142 is_irq = test_bit(FLAG_USED_AS_IRQ, &gdesc->flags);
5143 active_low = test_bit(FLAG_ACTIVE_LOW, &gdesc->flags);
5144 seq_printf(s, " gpio-%-3d (%-20.20s|%-20.20s) %s %s %s%s",
5145 gpio, gdesc->name ? gdesc->name : "", gdesc->label,
5146 is_out ? "out" : "in ",
5147 chip->get ? (chip->get(chip, i) ? "hi" : "lo") : "? ",
5148 is_irq ? "IRQ " : "",
5149 active_low ? "ACTIVE LOW" : "");
5150 seq_printf(s, "\n");
5154 static void *gpiolib_seq_start(struct seq_file *s, loff_t *pos)
5156 unsigned long flags;
5157 struct gpio_device *gdev = NULL;
5158 loff_t index = *pos;
5162 spin_lock_irqsave(&gpio_lock, flags);
5163 list_for_each_entry(gdev, &gpio_devices, list)
5165 spin_unlock_irqrestore(&gpio_lock, flags);
5168 spin_unlock_irqrestore(&gpio_lock, flags);
5173 static void *gpiolib_seq_next(struct seq_file *s, void *v, loff_t *pos)
5175 unsigned long flags;
5176 struct gpio_device *gdev = v;
5179 spin_lock_irqsave(&gpio_lock, flags);
5180 if (list_is_last(&gdev->list, &gpio_devices))
5183 ret = list_entry(gdev->list.next, struct gpio_device, list);
5184 spin_unlock_irqrestore(&gpio_lock, flags);
5192 static void gpiolib_seq_stop(struct seq_file *s, void *v)
5196 static int gpiolib_seq_show(struct seq_file *s, void *v)
5198 struct gpio_device *gdev = v;
5199 struct gpio_chip *chip = gdev->chip;
5200 struct device *parent;
5203 seq_printf(s, "%s%s: (dangling chip)", (char *)s->private,
5204 dev_name(&gdev->dev));
5208 seq_printf(s, "%s%s: GPIOs %d-%d", (char *)s->private,
5209 dev_name(&gdev->dev),
5210 gdev->base, gdev->base + gdev->ngpio - 1);
5211 parent = chip->parent;
5213 seq_printf(s, ", parent: %s/%s",
5214 parent->bus ? parent->bus->name : "no-bus",
5217 seq_printf(s, ", %s", chip->label);
5218 if (chip->can_sleep)
5219 seq_printf(s, ", can sleep");
5220 seq_printf(s, ":\n");
5223 chip->dbg_show(s, chip);
5225 gpiolib_dbg_show(s, gdev);
5230 static const struct seq_operations gpiolib_seq_ops = {
5231 .start = gpiolib_seq_start,
5232 .next = gpiolib_seq_next,
5233 .stop = gpiolib_seq_stop,
5234 .show = gpiolib_seq_show,
5237 static int gpiolib_open(struct inode *inode, struct file *file)
5239 return seq_open(file, &gpiolib_seq_ops);
5242 static const struct file_operations gpiolib_operations = {
5243 .owner = THIS_MODULE,
5244 .open = gpiolib_open,
5246 .llseek = seq_lseek,
5247 .release = seq_release,
5250 static int __init gpiolib_debugfs_init(void)
5252 /* /sys/kernel/debug/gpio */
5253 debugfs_create_file("gpio", S_IFREG | S_IRUGO, NULL, NULL,
5254 &gpiolib_operations);
5257 subsys_initcall(gpiolib_debugfs_init);
5259 #endif /* DEBUG_FS */