1 #include <linux/kernel.h>
2 #include <linux/module.h>
3 #include <linux/interrupt.h>
5 #include <linux/spinlock.h>
6 #include <linux/list.h>
7 #include <linux/device.h>
9 #include <linux/debugfs.h>
10 #include <linux/seq_file.h>
11 #include <linux/gpio.h>
12 #include <linux/of_gpio.h>
13 #include <linux/idr.h>
14 #include <linux/slab.h>
15 #include <linux/acpi.h>
16 #include <linux/gpio/driver.h>
17 #include <linux/gpio/machine.h>
18 #include <linux/pinctrl/consumer.h>
19 #include <linux/cdev.h>
21 #include <linux/uaccess.h>
22 #include <linux/compat.h>
23 #include <linux/anon_inodes.h>
24 #include <linux/kfifo.h>
25 #include <linux/poll.h>
26 #include <linux/timekeeping.h>
27 #include <uapi/linux/gpio.h>
31 #define CREATE_TRACE_POINTS
32 #include <trace/events/gpio.h>
34 /* Implementation infrastructure for GPIO interfaces.
36 * The GPIO programming interface allows for inlining speed-critical
37 * get/set operations for common cases, so that access to SOC-integrated
38 * GPIOs can sometimes cost only an instruction or two per bit.
42 /* When debugging, extend minimal trust to callers and platform code.
43 * Also emit diagnostic messages that may help initial bringup, when
44 * board setup or driver bugs are most common.
46 * Otherwise, minimize overhead in what may be bitbanging codepaths.
49 #define extra_checks 1
51 #define extra_checks 0
54 /* Device and char device-related information */
55 static DEFINE_IDA(gpio_ida);
56 static dev_t gpio_devt;
57 #define GPIO_DEV_MAX 256 /* 256 GPIO chip devices supported */
58 static struct bus_type gpio_bus_type = {
62 /* gpio_lock prevents conflicts during gpio_desc[] table updates.
63 * While any GPIO is requested, its gpio_chip is not removable;
64 * each GPIO's "requested" flag serves as a lock and refcount.
66 DEFINE_SPINLOCK(gpio_lock);
68 static DEFINE_MUTEX(gpio_lookup_lock);
69 static LIST_HEAD(gpio_lookup_list);
70 LIST_HEAD(gpio_devices);
72 static void gpiochip_free_hogs(struct gpio_chip *chip);
73 static void gpiochip_irqchip_remove(struct gpio_chip *gpiochip);
74 static int gpiochip_irqchip_init_valid_mask(struct gpio_chip *gpiochip);
75 static void gpiochip_irqchip_free_valid_mask(struct gpio_chip *gpiochip);
77 static bool gpiolib_initialized;
79 static inline void desc_set_label(struct gpio_desc *d, const char *label)
85 * Convert a GPIO number to its descriptor
87 struct gpio_desc *gpio_to_desc(unsigned gpio)
89 struct gpio_device *gdev;
92 spin_lock_irqsave(&gpio_lock, flags);
94 list_for_each_entry(gdev, &gpio_devices, list) {
95 if (gdev->base <= gpio &&
96 gdev->base + gdev->ngpio > gpio) {
97 spin_unlock_irqrestore(&gpio_lock, flags);
98 return &gdev->descs[gpio - gdev->base];
102 spin_unlock_irqrestore(&gpio_lock, flags);
104 if (!gpio_is_valid(gpio))
105 WARN(1, "invalid GPIO %d\n", gpio);
109 EXPORT_SYMBOL_GPL(gpio_to_desc);
112 * Get the GPIO descriptor corresponding to the given hw number for this chip.
114 struct gpio_desc *gpiochip_get_desc(struct gpio_chip *chip,
117 struct gpio_device *gdev = chip->gpiodev;
119 if (hwnum >= gdev->ngpio)
120 return ERR_PTR(-EINVAL);
122 return &gdev->descs[hwnum];
126 * Convert a GPIO descriptor to the integer namespace.
127 * This should disappear in the future but is needed since we still
128 * use GPIO numbers for error messages and sysfs nodes
130 int desc_to_gpio(const struct gpio_desc *desc)
132 return desc->gdev->base + (desc - &desc->gdev->descs[0]);
134 EXPORT_SYMBOL_GPL(desc_to_gpio);
138 * gpiod_to_chip - Return the GPIO chip to which a GPIO descriptor belongs
139 * @desc: descriptor to return the chip of
141 struct gpio_chip *gpiod_to_chip(const struct gpio_desc *desc)
143 if (!desc || !desc->gdev || !desc->gdev->chip)
145 return desc->gdev->chip;
147 EXPORT_SYMBOL_GPL(gpiod_to_chip);
149 /* dynamic allocation of GPIOs, e.g. on a hotplugged device */
150 static int gpiochip_find_base(int ngpio)
152 struct gpio_device *gdev;
153 int base = ARCH_NR_GPIOS - ngpio;
155 list_for_each_entry_reverse(gdev, &gpio_devices, list) {
156 /* found a free space? */
157 if (gdev->base + gdev->ngpio <= base)
160 /* nope, check the space right before the chip */
161 base = gdev->base - ngpio;
164 if (gpio_is_valid(base)) {
165 pr_debug("%s: found new base at %d\n", __func__, base);
168 pr_err("%s: cannot find free range\n", __func__);
174 * gpiod_get_direction - return the current direction of a GPIO
175 * @desc: GPIO to get the direction of
177 * Return GPIOF_DIR_IN or GPIOF_DIR_OUT, or an error code in case of error.
179 * This function may sleep if gpiod_cansleep() is true.
181 int gpiod_get_direction(struct gpio_desc *desc)
183 struct gpio_chip *chip;
185 int status = -EINVAL;
187 chip = gpiod_to_chip(desc);
188 offset = gpio_chip_hwgpio(desc);
190 if (!chip->get_direction)
193 status = chip->get_direction(chip, offset);
195 /* GPIOF_DIR_IN, or other positive */
197 clear_bit(FLAG_IS_OUT, &desc->flags);
201 set_bit(FLAG_IS_OUT, &desc->flags);
205 EXPORT_SYMBOL_GPL(gpiod_get_direction);
208 * Add a new chip to the global chips list, keeping the list of chips sorted
209 * by range(means [base, base + ngpio - 1]) order.
211 * Return -EBUSY if the new chip overlaps with some other chip's integer
214 static int gpiodev_add_to_list(struct gpio_device *gdev)
216 struct gpio_device *prev, *next;
218 if (list_empty(&gpio_devices)) {
219 /* initial entry in list */
220 list_add_tail(&gdev->list, &gpio_devices);
224 next = list_entry(gpio_devices.next, struct gpio_device, list);
225 if (gdev->base + gdev->ngpio <= next->base) {
226 /* add before first entry */
227 list_add(&gdev->list, &gpio_devices);
231 prev = list_entry(gpio_devices.prev, struct gpio_device, list);
232 if (prev->base + prev->ngpio <= gdev->base) {
233 /* add behind last entry */
234 list_add_tail(&gdev->list, &gpio_devices);
238 list_for_each_entry_safe(prev, next, &gpio_devices, list) {
239 /* at the end of the list */
240 if (&next->list == &gpio_devices)
243 /* add between prev and next */
244 if (prev->base + prev->ngpio <= gdev->base
245 && gdev->base + gdev->ngpio <= next->base) {
246 list_add(&gdev->list, &prev->list);
251 dev_err(&gdev->dev, "GPIO integer space overlap, cannot add chip\n");
256 * Convert a GPIO name to its descriptor
258 static struct gpio_desc *gpio_name_to_desc(const char * const name)
260 struct gpio_device *gdev;
263 spin_lock_irqsave(&gpio_lock, flags);
265 list_for_each_entry(gdev, &gpio_devices, list) {
268 for (i = 0; i != gdev->ngpio; ++i) {
269 struct gpio_desc *desc = &gdev->descs[i];
271 if (!desc->name || !name)
274 if (!strcmp(desc->name, name)) {
275 spin_unlock_irqrestore(&gpio_lock, flags);
281 spin_unlock_irqrestore(&gpio_lock, flags);
287 * Takes the names from gc->names and checks if they are all unique. If they
288 * are, they are assigned to their gpio descriptors.
290 * Warning if one of the names is already used for a different GPIO.
292 static int gpiochip_set_desc_names(struct gpio_chip *gc)
294 struct gpio_device *gdev = gc->gpiodev;
300 /* First check all names if they are unique */
301 for (i = 0; i != gc->ngpio; ++i) {
302 struct gpio_desc *gpio;
304 gpio = gpio_name_to_desc(gc->names[i]);
307 "Detected name collision for GPIO name '%s'\n",
311 /* Then add all names to the GPIO descriptors */
312 for (i = 0; i != gc->ngpio; ++i)
313 gdev->descs[i].name = gc->names[i];
319 * GPIO line handle management
323 * struct linehandle_state - contains the state of a userspace handle
324 * @gdev: the GPIO device the handle pertains to
325 * @label: consumer label used to tag descriptors
326 * @descs: the GPIO descriptors held by this handle
327 * @numdescs: the number of descriptors held in the descs array
329 struct linehandle_state {
330 struct gpio_device *gdev;
332 struct gpio_desc *descs[GPIOHANDLES_MAX];
336 static long linehandle_ioctl(struct file *filep, unsigned int cmd,
339 struct linehandle_state *lh = filep->private_data;
340 void __user *ip = (void __user *)arg;
341 struct gpiohandle_data ghd;
344 if (cmd == GPIOHANDLE_GET_LINE_VALUES_IOCTL) {
347 /* TODO: check if descriptors are really input */
348 for (i = 0; i < lh->numdescs; i++) {
349 val = gpiod_get_value_cansleep(lh->descs[i]);
355 if (copy_to_user(ip, &ghd, sizeof(ghd)))
359 } else if (cmd == GPIOHANDLE_SET_LINE_VALUES_IOCTL) {
360 int vals[GPIOHANDLES_MAX];
362 /* TODO: check if descriptors are really output */
363 if (copy_from_user(&ghd, ip, sizeof(ghd)))
366 /* Clamp all values to [0,1] */
367 for (i = 0; i < lh->numdescs; i++)
368 vals[i] = !!ghd.values[i];
370 /* Reuse the array setting function */
371 gpiod_set_array_value_complex(false,
382 static long linehandle_ioctl_compat(struct file *filep, unsigned int cmd,
385 return linehandle_ioctl(filep, cmd, (unsigned long)compat_ptr(arg));
389 static int linehandle_release(struct inode *inode, struct file *filep)
391 struct linehandle_state *lh = filep->private_data;
392 struct gpio_device *gdev = lh->gdev;
395 for (i = 0; i < lh->numdescs; i++)
396 gpiod_free(lh->descs[i]);
399 put_device(&gdev->dev);
403 static const struct file_operations linehandle_fileops = {
404 .release = linehandle_release,
405 .owner = THIS_MODULE,
406 .llseek = noop_llseek,
407 .unlocked_ioctl = linehandle_ioctl,
409 .compat_ioctl = linehandle_ioctl_compat,
413 static int linehandle_create(struct gpio_device *gdev, void __user *ip)
415 struct gpiohandle_request handlereq;
416 struct linehandle_state *lh;
419 if (copy_from_user(&handlereq, ip, sizeof(handlereq)))
421 if ((handlereq.lines == 0) || (handlereq.lines > GPIOHANDLES_MAX))
424 lh = kzalloc(sizeof(*lh), GFP_KERNEL);
428 get_device(&gdev->dev);
430 /* Make sure this is terminated */
431 handlereq.consumer_label[sizeof(handlereq.consumer_label)-1] = '\0';
432 if (strlen(handlereq.consumer_label)) {
433 lh->label = kstrdup(handlereq.consumer_label,
441 /* Request each GPIO */
442 for (i = 0; i < handlereq.lines; i++) {
443 u32 offset = handlereq.lineoffsets[i];
444 u32 lflags = handlereq.flags;
445 struct gpio_desc *desc;
447 if (offset >= gdev->ngpio) {
452 desc = &gdev->descs[offset];
453 ret = gpiod_request(desc, lh->label);
458 if (lflags & GPIOHANDLE_REQUEST_ACTIVE_LOW)
459 set_bit(FLAG_ACTIVE_LOW, &desc->flags);
460 if (lflags & GPIOHANDLE_REQUEST_OPEN_DRAIN)
461 set_bit(FLAG_OPEN_DRAIN, &desc->flags);
462 if (lflags & GPIOHANDLE_REQUEST_OPEN_SOURCE)
463 set_bit(FLAG_OPEN_SOURCE, &desc->flags);
466 * Lines have to be requested explicitly for input
467 * or output, else the line will be treated "as is".
469 if (lflags & GPIOHANDLE_REQUEST_OUTPUT) {
470 int val = !!handlereq.default_values[i];
472 ret = gpiod_direction_output(desc, val);
475 } else if (lflags & GPIOHANDLE_REQUEST_INPUT) {
476 ret = gpiod_direction_input(desc);
480 dev_dbg(&gdev->dev, "registered chardev handle for line %d\n",
483 /* Let i point at the last handle */
485 lh->numdescs = handlereq.lines;
487 fd = anon_inode_getfd("gpio-linehandle",
490 O_RDONLY | O_CLOEXEC);
497 if (copy_to_user(ip, &handlereq, sizeof(handlereq))) {
502 dev_dbg(&gdev->dev, "registered chardev handle for %d lines\n",
509 gpiod_free(lh->descs[i]);
513 put_device(&gdev->dev);
518 * GPIO line event management
522 * struct lineevent_state - contains the state of a userspace event
523 * @gdev: the GPIO device the event pertains to
524 * @label: consumer label used to tag descriptors
525 * @desc: the GPIO descriptor held by this event
526 * @eflags: the event flags this line was requested with
527 * @irq: the interrupt that trigger in response to events on this GPIO
528 * @wait: wait queue that handles blocking reads of events
529 * @events: KFIFO for the GPIO events
530 * @read_lock: mutex lock to protect reads from colliding with adding
531 * new events to the FIFO
533 struct lineevent_state {
534 struct gpio_device *gdev;
536 struct gpio_desc *desc;
539 wait_queue_head_t wait;
540 DECLARE_KFIFO(events, struct gpioevent_data, 16);
541 struct mutex read_lock;
544 static unsigned int lineevent_poll(struct file *filep,
545 struct poll_table_struct *wait)
547 struct lineevent_state *le = filep->private_data;
548 unsigned int events = 0;
550 poll_wait(filep, &le->wait, wait);
552 if (!kfifo_is_empty(&le->events))
553 events = POLLIN | POLLRDNORM;
559 static ssize_t lineevent_read(struct file *filep,
564 struct lineevent_state *le = filep->private_data;
568 if (count < sizeof(struct gpioevent_data))
572 if (kfifo_is_empty(&le->events)) {
573 if (filep->f_flags & O_NONBLOCK)
576 ret = wait_event_interruptible(le->wait,
577 !kfifo_is_empty(&le->events));
582 if (mutex_lock_interruptible(&le->read_lock))
584 ret = kfifo_to_user(&le->events, buf, count, &copied);
585 mutex_unlock(&le->read_lock);
591 * If we couldn't read anything from the fifo (a different
592 * thread might have been faster) we either return -EAGAIN if
593 * the file descriptor is non-blocking, otherwise we go back to
594 * sleep and wait for more data to arrive.
596 if (copied == 0 && (filep->f_flags & O_NONBLOCK))
599 } while (copied == 0);
604 static int lineevent_release(struct inode *inode, struct file *filep)
606 struct lineevent_state *le = filep->private_data;
607 struct gpio_device *gdev = le->gdev;
609 free_irq(le->irq, le);
610 gpiod_free(le->desc);
613 put_device(&gdev->dev);
617 static long lineevent_ioctl(struct file *filep, unsigned int cmd,
620 struct lineevent_state *le = filep->private_data;
621 void __user *ip = (void __user *)arg;
622 struct gpiohandle_data ghd;
625 * We can get the value for an event line but not set it,
626 * because it is input by definition.
628 if (cmd == GPIOHANDLE_GET_LINE_VALUES_IOCTL) {
631 memset(&ghd, 0, sizeof(ghd));
633 val = gpiod_get_value_cansleep(le->desc);
638 if (copy_to_user(ip, &ghd, sizeof(ghd)))
647 static long lineevent_ioctl_compat(struct file *filep, unsigned int cmd,
650 return lineevent_ioctl(filep, cmd, (unsigned long)compat_ptr(arg));
654 static const struct file_operations lineevent_fileops = {
655 .release = lineevent_release,
656 .read = lineevent_read,
657 .poll = lineevent_poll,
658 .owner = THIS_MODULE,
659 .llseek = noop_llseek,
660 .unlocked_ioctl = lineevent_ioctl,
662 .compat_ioctl = lineevent_ioctl_compat,
666 static irqreturn_t lineevent_irq_thread(int irq, void *p)
668 struct lineevent_state *le = p;
669 struct gpioevent_data ge;
672 ge.timestamp = ktime_get_real_ns();
674 if (le->eflags & GPIOEVENT_REQUEST_BOTH_EDGES) {
675 int level = gpiod_get_value_cansleep(le->desc);
678 /* Emit low-to-high event */
679 ge.id = GPIOEVENT_EVENT_RISING_EDGE;
681 /* Emit high-to-low event */
682 ge.id = GPIOEVENT_EVENT_FALLING_EDGE;
683 } else if (le->eflags & GPIOEVENT_REQUEST_RISING_EDGE) {
684 /* Emit low-to-high event */
685 ge.id = GPIOEVENT_EVENT_RISING_EDGE;
686 } else if (le->eflags & GPIOEVENT_REQUEST_FALLING_EDGE) {
687 /* Emit high-to-low event */
688 ge.id = GPIOEVENT_EVENT_FALLING_EDGE;
693 ret = kfifo_put(&le->events, ge);
695 wake_up_poll(&le->wait, POLLIN);
700 static int lineevent_create(struct gpio_device *gdev, void __user *ip)
702 struct gpioevent_request eventreq;
703 struct lineevent_state *le;
704 struct gpio_desc *desc;
712 if (copy_from_user(&eventreq, ip, sizeof(eventreq)))
715 le = kzalloc(sizeof(*le), GFP_KERNEL);
719 get_device(&gdev->dev);
721 /* Make sure this is terminated */
722 eventreq.consumer_label[sizeof(eventreq.consumer_label)-1] = '\0';
723 if (strlen(eventreq.consumer_label)) {
724 le->label = kstrdup(eventreq.consumer_label,
732 offset = eventreq.lineoffset;
733 lflags = eventreq.handleflags;
734 eflags = eventreq.eventflags;
736 if (offset >= gdev->ngpio) {
741 /* This is just wrong: we don't look for events on output lines */
742 if (lflags & GPIOHANDLE_REQUEST_OUTPUT) {
747 desc = &gdev->descs[offset];
748 ret = gpiod_request(desc, le->label);
754 if (lflags & GPIOHANDLE_REQUEST_ACTIVE_LOW)
755 set_bit(FLAG_ACTIVE_LOW, &desc->flags);
756 if (lflags & GPIOHANDLE_REQUEST_OPEN_DRAIN)
757 set_bit(FLAG_OPEN_DRAIN, &desc->flags);
758 if (lflags & GPIOHANDLE_REQUEST_OPEN_SOURCE)
759 set_bit(FLAG_OPEN_SOURCE, &desc->flags);
761 ret = gpiod_direction_input(desc);
765 le->irq = gpiod_to_irq(desc);
771 if (eflags & GPIOEVENT_REQUEST_RISING_EDGE)
772 irqflags |= IRQF_TRIGGER_RISING;
773 if (eflags & GPIOEVENT_REQUEST_FALLING_EDGE)
774 irqflags |= IRQF_TRIGGER_FALLING;
775 irqflags |= IRQF_ONESHOT;
776 irqflags |= IRQF_SHARED;
778 INIT_KFIFO(le->events);
779 init_waitqueue_head(&le->wait);
780 mutex_init(&le->read_lock);
782 /* Request a thread to read the events */
783 ret = request_threaded_irq(le->irq,
785 lineevent_irq_thread,
792 fd = anon_inode_getfd("gpio-event",
795 O_RDONLY | O_CLOEXEC);
802 if (copy_to_user(ip, &eventreq, sizeof(eventreq))) {
810 free_irq(le->irq, le);
812 gpiod_free(le->desc);
817 put_device(&gdev->dev);
822 * gpio_ioctl() - ioctl handler for the GPIO chardev
824 static long gpio_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
826 struct gpio_device *gdev = filp->private_data;
827 struct gpio_chip *chip = gdev->chip;
828 void __user *ip = (void __user *)arg;
830 /* We fail any subsequent ioctl():s when the chip is gone */
834 /* Fill in the struct and pass to userspace */
835 if (cmd == GPIO_GET_CHIPINFO_IOCTL) {
836 struct gpiochip_info chipinfo;
838 memset(&chipinfo, 0, sizeof(chipinfo));
840 strncpy(chipinfo.name, dev_name(&gdev->dev),
841 sizeof(chipinfo.name));
842 chipinfo.name[sizeof(chipinfo.name)-1] = '\0';
843 strncpy(chipinfo.label, gdev->label,
844 sizeof(chipinfo.label));
845 chipinfo.label[sizeof(chipinfo.label)-1] = '\0';
846 chipinfo.lines = gdev->ngpio;
847 if (copy_to_user(ip, &chipinfo, sizeof(chipinfo)))
850 } else if (cmd == GPIO_GET_LINEINFO_IOCTL) {
851 struct gpioline_info lineinfo;
852 struct gpio_desc *desc;
854 if (copy_from_user(&lineinfo, ip, sizeof(lineinfo)))
856 if (lineinfo.line_offset >= gdev->ngpio)
859 desc = &gdev->descs[lineinfo.line_offset];
861 strncpy(lineinfo.name, desc->name,
862 sizeof(lineinfo.name));
863 lineinfo.name[sizeof(lineinfo.name)-1] = '\0';
865 lineinfo.name[0] = '\0';
868 strncpy(lineinfo.consumer, desc->label,
869 sizeof(lineinfo.consumer));
870 lineinfo.consumer[sizeof(lineinfo.consumer)-1] = '\0';
872 lineinfo.consumer[0] = '\0';
876 * Userspace only need to know that the kernel is using
877 * this GPIO so it can't use it.
880 if (test_bit(FLAG_REQUESTED, &desc->flags) ||
881 test_bit(FLAG_IS_HOGGED, &desc->flags) ||
882 test_bit(FLAG_USED_AS_IRQ, &desc->flags) ||
883 test_bit(FLAG_EXPORT, &desc->flags) ||
884 test_bit(FLAG_SYSFS, &desc->flags))
885 lineinfo.flags |= GPIOLINE_FLAG_KERNEL;
886 if (test_bit(FLAG_IS_OUT, &desc->flags))
887 lineinfo.flags |= GPIOLINE_FLAG_IS_OUT;
888 if (test_bit(FLAG_ACTIVE_LOW, &desc->flags))
889 lineinfo.flags |= GPIOLINE_FLAG_ACTIVE_LOW;
890 if (test_bit(FLAG_OPEN_DRAIN, &desc->flags))
891 lineinfo.flags |= GPIOLINE_FLAG_OPEN_DRAIN;
892 if (test_bit(FLAG_OPEN_SOURCE, &desc->flags))
893 lineinfo.flags |= GPIOLINE_FLAG_OPEN_SOURCE;
895 if (copy_to_user(ip, &lineinfo, sizeof(lineinfo)))
898 } else if (cmd == GPIO_GET_LINEHANDLE_IOCTL) {
899 return linehandle_create(gdev, ip);
900 } else if (cmd == GPIO_GET_LINEEVENT_IOCTL) {
901 return lineevent_create(gdev, ip);
907 static long gpio_ioctl_compat(struct file *filp, unsigned int cmd,
910 return gpio_ioctl(filp, cmd, (unsigned long)compat_ptr(arg));
915 * gpio_chrdev_open() - open the chardev for ioctl operations
916 * @inode: inode for this chardev
917 * @filp: file struct for storing private data
918 * Returns 0 on success
920 static int gpio_chrdev_open(struct inode *inode, struct file *filp)
922 struct gpio_device *gdev = container_of(inode->i_cdev,
923 struct gpio_device, chrdev);
925 /* Fail on open if the backing gpiochip is gone */
926 if (!gdev || !gdev->chip)
928 get_device(&gdev->dev);
929 filp->private_data = gdev;
934 * gpio_chrdev_release() - close chardev after ioctl operations
935 * @inode: inode for this chardev
936 * @filp: file struct for storing private data
937 * Returns 0 on success
939 static int gpio_chrdev_release(struct inode *inode, struct file *filp)
941 struct gpio_device *gdev = container_of(inode->i_cdev,
942 struct gpio_device, chrdev);
946 put_device(&gdev->dev);
951 static const struct file_operations gpio_fileops = {
952 .release = gpio_chrdev_release,
953 .open = gpio_chrdev_open,
954 .owner = THIS_MODULE,
955 .llseek = noop_llseek,
956 .unlocked_ioctl = gpio_ioctl,
958 .compat_ioctl = gpio_ioctl_compat,
962 static void gpiodevice_release(struct device *dev)
964 struct gpio_device *gdev = dev_get_drvdata(dev);
966 list_del(&gdev->list);
967 ida_simple_remove(&gpio_ida, gdev->id);
973 static int gpiochip_setup_dev(struct gpio_device *gdev)
977 cdev_init(&gdev->chrdev, &gpio_fileops);
978 gdev->chrdev.owner = THIS_MODULE;
979 gdev->chrdev.kobj.parent = &gdev->dev.kobj;
980 gdev->dev.devt = MKDEV(MAJOR(gpio_devt), gdev->id);
981 status = cdev_add(&gdev->chrdev, gdev->dev.devt, 1);
983 chip_warn(gdev->chip, "failed to add char device %d:%d\n",
984 MAJOR(gpio_devt), gdev->id);
986 chip_dbg(gdev->chip, "added GPIO chardev (%d:%d)\n",
987 MAJOR(gpio_devt), gdev->id);
988 status = device_add(&gdev->dev);
990 goto err_remove_chardev;
992 status = gpiochip_sysfs_register(gdev);
994 goto err_remove_device;
996 /* From this point, the .release() function cleans up gpio_device */
997 gdev->dev.release = gpiodevice_release;
998 pr_debug("%s: registered GPIOs %d to %d on device: %s (%s)\n",
999 __func__, gdev->base, gdev->base + gdev->ngpio - 1,
1000 dev_name(&gdev->dev), gdev->chip->label ? : "generic");
1005 device_del(&gdev->dev);
1007 cdev_del(&gdev->chrdev);
1011 static void gpiochip_setup_devs(void)
1013 struct gpio_device *gdev;
1016 list_for_each_entry(gdev, &gpio_devices, list) {
1017 err = gpiochip_setup_dev(gdev);
1019 pr_err("%s: Failed to initialize gpio device (%d)\n",
1020 dev_name(&gdev->dev), err);
1025 * gpiochip_add_data() - register a gpio_chip
1026 * @chip: the chip to register, with chip->base initialized
1027 * Context: potentially before irqs will work
1029 * Returns a negative errno if the chip can't be registered, such as
1030 * because the chip->base is invalid or already associated with a
1031 * different chip. Otherwise it returns zero as a success code.
1033 * When gpiochip_add_data() is called very early during boot, so that GPIOs
1034 * can be freely used, the chip->parent device must be registered before
1035 * the gpio framework's arch_initcall(). Otherwise sysfs initialization
1036 * for GPIOs will fail rudely.
1038 * gpiochip_add_data() must only be called after gpiolib initialization,
1039 * ie after core_initcall().
1041 * If chip->base is negative, this requests dynamic assignment of
1042 * a range of valid GPIOs.
1044 int gpiochip_add_data(struct gpio_chip *chip, void *data)
1046 unsigned long flags;
1049 int base = chip->base;
1050 struct gpio_device *gdev;
1053 * First: allocate and populate the internal stat container, and
1054 * set up the struct device.
1056 gdev = kzalloc(sizeof(*gdev), GFP_KERNEL);
1059 gdev->dev.bus = &gpio_bus_type;
1061 chip->gpiodev = gdev;
1063 gdev->dev.parent = chip->parent;
1064 gdev->dev.of_node = chip->parent->of_node;
1067 #ifdef CONFIG_OF_GPIO
1068 /* If the gpiochip has an assigned OF node this takes precedence */
1070 gdev->dev.of_node = chip->of_node;
1073 gdev->id = ida_simple_get(&gpio_ida, 0, 0, GFP_KERNEL);
1078 dev_set_name(&gdev->dev, "gpiochip%d", gdev->id);
1079 device_initialize(&gdev->dev);
1080 dev_set_drvdata(&gdev->dev, gdev);
1081 if (chip->parent && chip->parent->driver)
1082 gdev->owner = chip->parent->driver->owner;
1083 else if (chip->owner)
1084 /* TODO: remove chip->owner */
1085 gdev->owner = chip->owner;
1087 gdev->owner = THIS_MODULE;
1089 gdev->descs = kcalloc(chip->ngpio, sizeof(gdev->descs[0]), GFP_KERNEL);
1095 if (chip->ngpio == 0) {
1096 chip_err(chip, "tried to insert a GPIO chip with zero lines\n");
1098 goto err_free_descs;
1102 gdev->label = kstrdup(chip->label, GFP_KERNEL);
1104 gdev->label = kstrdup("unknown", GFP_KERNEL);
1107 goto err_free_descs;
1110 gdev->ngpio = chip->ngpio;
1113 spin_lock_irqsave(&gpio_lock, flags);
1116 * TODO: this allocates a Linux GPIO number base in the global
1117 * GPIO numberspace for this chip. In the long run we want to
1118 * get *rid* of this numberspace and use only descriptors, but
1119 * it may be a pipe dream. It will not happen before we get rid
1120 * of the sysfs interface anyways.
1123 base = gpiochip_find_base(chip->ngpio);
1126 spin_unlock_irqrestore(&gpio_lock, flags);
1127 goto err_free_label;
1130 * TODO: it should not be necessary to reflect the assigned
1131 * base outside of the GPIO subsystem. Go over drivers and
1132 * see if anyone makes use of this, else drop this and assign
1139 status = gpiodev_add_to_list(gdev);
1141 spin_unlock_irqrestore(&gpio_lock, flags);
1142 goto err_free_label;
1145 spin_unlock_irqrestore(&gpio_lock, flags);
1147 for (i = 0; i < chip->ngpio; i++) {
1148 struct gpio_desc *desc = &gdev->descs[i];
1152 * REVISIT: most hardware initializes GPIOs as inputs
1153 * (often with pullups enabled) so power usage is
1154 * minimized. Linux code should set the gpio direction
1155 * first thing; but until it does, and in case
1156 * chip->get_direction is not set, we may expose the
1157 * wrong direction in sysfs.
1160 if (chip->get_direction) {
1162 * If we have .get_direction, set up the initial
1163 * direction flag from the hardware.
1165 int dir = chip->get_direction(chip, i);
1168 set_bit(FLAG_IS_OUT, &desc->flags);
1169 } else if (!chip->direction_input) {
1171 * If the chip lacks the .direction_input callback
1172 * we logically assume all lines are outputs.
1174 set_bit(FLAG_IS_OUT, &desc->flags);
1178 #ifdef CONFIG_PINCTRL
1179 INIT_LIST_HEAD(&gdev->pin_ranges);
1182 status = gpiochip_set_desc_names(chip);
1184 goto err_remove_from_list;
1186 status = gpiochip_irqchip_init_valid_mask(chip);
1188 goto err_remove_from_list;
1190 status = of_gpiochip_add(chip);
1192 goto err_remove_chip;
1194 acpi_gpiochip_add(chip);
1197 * By first adding the chardev, and then adding the device,
1198 * we get a device node entry in sysfs under
1199 * /sys/bus/gpio/devices/gpiochipN/dev that can be used for
1200 * coldplug of device nodes and other udev business.
1201 * We can do this only if gpiolib has been initialized.
1202 * Otherwise, defer until later.
1204 if (gpiolib_initialized) {
1205 status = gpiochip_setup_dev(gdev);
1207 goto err_remove_chip;
1212 acpi_gpiochip_remove(chip);
1213 gpiochip_free_hogs(chip);
1214 of_gpiochip_remove(chip);
1215 gpiochip_irqchip_free_valid_mask(chip);
1216 err_remove_from_list:
1217 spin_lock_irqsave(&gpio_lock, flags);
1218 list_del(&gdev->list);
1219 spin_unlock_irqrestore(&gpio_lock, flags);
1225 ida_simple_remove(&gpio_ida, gdev->id);
1226 /* failures here can mean systems won't boot... */
1227 pr_err("%s: GPIOs %d..%d (%s) failed to register\n", __func__,
1228 gdev->base, gdev->base + gdev->ngpio - 1,
1229 chip->label ? : "generic");
1233 EXPORT_SYMBOL_GPL(gpiochip_add_data);
1236 * gpiochip_get_data() - get per-subdriver data for the chip
1238 void *gpiochip_get_data(struct gpio_chip *chip)
1240 return chip->gpiodev->data;
1242 EXPORT_SYMBOL_GPL(gpiochip_get_data);
1245 * gpiochip_remove() - unregister a gpio_chip
1246 * @chip: the chip to unregister
1248 * A gpio_chip with any GPIOs still requested may not be removed.
1250 void gpiochip_remove(struct gpio_chip *chip)
1252 struct gpio_device *gdev = chip->gpiodev;
1253 struct gpio_desc *desc;
1254 unsigned long flags;
1256 bool requested = false;
1258 /* FIXME: should the legacy sysfs handling be moved to gpio_device? */
1259 gpiochip_sysfs_unregister(gdev);
1260 /* Numb the device, cancelling all outstanding operations */
1262 gpiochip_irqchip_remove(chip);
1263 acpi_gpiochip_remove(chip);
1264 gpiochip_remove_pin_ranges(chip);
1265 gpiochip_free_hogs(chip);
1266 of_gpiochip_remove(chip);
1268 * We accept no more calls into the driver from this point, so
1269 * NULL the driver data pointer
1273 spin_lock_irqsave(&gpio_lock, flags);
1274 for (i = 0; i < gdev->ngpio; i++) {
1275 desc = &gdev->descs[i];
1276 if (test_bit(FLAG_REQUESTED, &desc->flags))
1279 spin_unlock_irqrestore(&gpio_lock, flags);
1282 dev_crit(&gdev->dev,
1283 "REMOVING GPIOCHIP WITH GPIOS STILL REQUESTED\n");
1286 * The gpiochip side puts its use of the device to rest here:
1287 * if there are no userspace clients, the chardev and device will
1288 * be removed, else it will be dangling until the last user is
1291 cdev_del(&gdev->chrdev);
1292 device_del(&gdev->dev);
1293 put_device(&gdev->dev);
1295 EXPORT_SYMBOL_GPL(gpiochip_remove);
1297 static void devm_gpio_chip_release(struct device *dev, void *res)
1299 struct gpio_chip *chip = *(struct gpio_chip **)res;
1301 gpiochip_remove(chip);
1304 static int devm_gpio_chip_match(struct device *dev, void *res, void *data)
1307 struct gpio_chip **r = res;
1318 * devm_gpiochip_add_data() - Resource manager piochip_add_data()
1319 * @dev: the device pointer on which irq_chip belongs to.
1320 * @chip: the chip to register, with chip->base initialized
1321 * Context: potentially before irqs will work
1323 * Returns a negative errno if the chip can't be registered, such as
1324 * because the chip->base is invalid or already associated with a
1325 * different chip. Otherwise it returns zero as a success code.
1327 * The gpio chip automatically be released when the device is unbound.
1329 int devm_gpiochip_add_data(struct device *dev, struct gpio_chip *chip,
1332 struct gpio_chip **ptr;
1335 ptr = devres_alloc(devm_gpio_chip_release, sizeof(*ptr),
1340 ret = gpiochip_add_data(chip, data);
1347 devres_add(dev, ptr);
1351 EXPORT_SYMBOL_GPL(devm_gpiochip_add_data);
1354 * devm_gpiochip_remove() - Resource manager of gpiochip_remove()
1355 * @dev: device for which which resource was allocated
1356 * @chip: the chip to remove
1358 * A gpio_chip with any GPIOs still requested may not be removed.
1360 void devm_gpiochip_remove(struct device *dev, struct gpio_chip *chip)
1364 ret = devres_release(dev, devm_gpio_chip_release,
1365 devm_gpio_chip_match, chip);
1369 EXPORT_SYMBOL_GPL(devm_gpiochip_remove);
1372 * gpiochip_find() - iterator for locating a specific gpio_chip
1373 * @data: data to pass to match function
1374 * @callback: Callback function to check gpio_chip
1376 * Similar to bus_find_device. It returns a reference to a gpio_chip as
1377 * determined by a user supplied @match callback. The callback should return
1378 * 0 if the device doesn't match and non-zero if it does. If the callback is
1379 * non-zero, this function will return to the caller and not iterate over any
1382 struct gpio_chip *gpiochip_find(void *data,
1383 int (*match)(struct gpio_chip *chip,
1386 struct gpio_device *gdev;
1387 struct gpio_chip *chip = NULL;
1388 unsigned long flags;
1390 spin_lock_irqsave(&gpio_lock, flags);
1391 list_for_each_entry(gdev, &gpio_devices, list)
1392 if (gdev->chip && match(gdev->chip, data)) {
1397 spin_unlock_irqrestore(&gpio_lock, flags);
1401 EXPORT_SYMBOL_GPL(gpiochip_find);
1403 static int gpiochip_match_name(struct gpio_chip *chip, void *data)
1405 const char *name = data;
1407 return !strcmp(chip->label, name);
1410 static struct gpio_chip *find_chip_by_name(const char *name)
1412 return gpiochip_find((void *)name, gpiochip_match_name);
1415 #ifdef CONFIG_GPIOLIB_IRQCHIP
1418 * The following is irqchip helper code for gpiochips.
1421 static int gpiochip_irqchip_init_valid_mask(struct gpio_chip *gpiochip)
1425 if (!gpiochip->irq_need_valid_mask)
1428 gpiochip->irq_valid_mask = kcalloc(BITS_TO_LONGS(gpiochip->ngpio),
1429 sizeof(long), GFP_KERNEL);
1430 if (!gpiochip->irq_valid_mask)
1433 /* Assume by default all GPIOs are valid */
1434 for (i = 0; i < gpiochip->ngpio; i++)
1435 set_bit(i, gpiochip->irq_valid_mask);
1440 static void gpiochip_irqchip_free_valid_mask(struct gpio_chip *gpiochip)
1442 kfree(gpiochip->irq_valid_mask);
1443 gpiochip->irq_valid_mask = NULL;
1446 static bool gpiochip_irqchip_irq_valid(const struct gpio_chip *gpiochip,
1447 unsigned int offset)
1449 /* No mask means all valid */
1450 if (likely(!gpiochip->irq_valid_mask))
1452 return test_bit(offset, gpiochip->irq_valid_mask);
1456 * gpiochip_set_chained_irqchip() - sets a chained irqchip to a gpiochip
1457 * @gpiochip: the gpiochip to set the irqchip chain to
1458 * @irqchip: the irqchip to chain to the gpiochip
1459 * @parent_irq: the irq number corresponding to the parent IRQ for this
1461 * @parent_handler: the parent interrupt handler for the accumulated IRQ
1462 * coming out of the gpiochip. If the interrupt is nested rather than
1463 * cascaded, pass NULL in this handler argument
1465 void gpiochip_set_chained_irqchip(struct gpio_chip *gpiochip,
1466 struct irq_chip *irqchip,
1468 irq_flow_handler_t parent_handler)
1470 unsigned int offset;
1472 if (!gpiochip->irqdomain) {
1473 chip_err(gpiochip, "called %s before setting up irqchip\n",
1478 if (parent_handler) {
1479 if (gpiochip->can_sleep) {
1481 "you cannot have chained interrupts on a "
1482 "chip that may sleep\n");
1486 * The parent irqchip is already using the chip_data for this
1487 * irqchip, so our callbacks simply use the handler_data.
1489 irq_set_chained_handler_and_data(parent_irq, parent_handler,
1492 gpiochip->irq_parent = parent_irq;
1495 /* Set the parent IRQ for all affected IRQs */
1496 for (offset = 0; offset < gpiochip->ngpio; offset++) {
1497 if (!gpiochip_irqchip_irq_valid(gpiochip, offset))
1499 irq_set_parent(irq_find_mapping(gpiochip->irqdomain, offset),
1503 EXPORT_SYMBOL_GPL(gpiochip_set_chained_irqchip);
1506 * gpiochip_irq_map() - maps an IRQ into a GPIO irqchip
1507 * @d: the irqdomain used by this irqchip
1508 * @irq: the global irq number used by this GPIO irqchip irq
1509 * @hwirq: the local IRQ/GPIO line offset on this gpiochip
1511 * This function will set up the mapping for a certain IRQ line on a
1512 * gpiochip by assigning the gpiochip as chip data, and using the irqchip
1513 * stored inside the gpiochip.
1515 static int gpiochip_irq_map(struct irq_domain *d, unsigned int irq,
1516 irq_hw_number_t hwirq)
1518 struct gpio_chip *chip = d->host_data;
1520 irq_set_chip_data(irq, chip);
1522 * This lock class tells lockdep that GPIO irqs are in a different
1523 * category than their parents, so it won't report false recursion.
1525 irq_set_lockdep_class(irq, chip->lock_key);
1526 irq_set_chip_and_handler(irq, chip->irqchip, chip->irq_handler);
1527 /* Chips that can sleep need nested thread handlers */
1528 if (chip->can_sleep && !chip->irq_not_threaded)
1529 irq_set_nested_thread(irq, 1);
1530 irq_set_noprobe(irq);
1533 * No set-up of the hardware will happen if IRQ_TYPE_NONE
1534 * is passed as default type.
1536 if (chip->irq_default_type != IRQ_TYPE_NONE)
1537 irq_set_irq_type(irq, chip->irq_default_type);
1542 static void gpiochip_irq_unmap(struct irq_domain *d, unsigned int irq)
1544 struct gpio_chip *chip = d->host_data;
1546 if (chip->can_sleep)
1547 irq_set_nested_thread(irq, 0);
1548 irq_set_chip_and_handler(irq, NULL, NULL);
1549 irq_set_chip_data(irq, NULL);
1552 static const struct irq_domain_ops gpiochip_domain_ops = {
1553 .map = gpiochip_irq_map,
1554 .unmap = gpiochip_irq_unmap,
1555 /* Virtually all GPIO irqchips are twocell:ed */
1556 .xlate = irq_domain_xlate_twocell,
1559 static int gpiochip_irq_reqres(struct irq_data *d)
1561 struct gpio_chip *chip = irq_data_get_irq_chip_data(d);
1563 if (!try_module_get(chip->gpiodev->owner))
1566 if (gpiochip_lock_as_irq(chip, d->hwirq)) {
1568 "unable to lock HW IRQ %lu for IRQ\n",
1570 module_put(chip->gpiodev->owner);
1576 static void gpiochip_irq_relres(struct irq_data *d)
1578 struct gpio_chip *chip = irq_data_get_irq_chip_data(d);
1580 gpiochip_unlock_as_irq(chip, d->hwirq);
1581 module_put(chip->gpiodev->owner);
1584 static int gpiochip_to_irq(struct gpio_chip *chip, unsigned offset)
1586 return irq_find_mapping(chip->irqdomain, offset);
1590 * gpiochip_irqchip_remove() - removes an irqchip added to a gpiochip
1591 * @gpiochip: the gpiochip to remove the irqchip from
1593 * This is called only from gpiochip_remove()
1595 static void gpiochip_irqchip_remove(struct gpio_chip *gpiochip)
1597 unsigned int offset;
1599 acpi_gpiochip_free_interrupts(gpiochip);
1601 if (gpiochip->irq_parent) {
1602 irq_set_chained_handler(gpiochip->irq_parent, NULL);
1603 irq_set_handler_data(gpiochip->irq_parent, NULL);
1606 /* Remove all IRQ mappings and delete the domain */
1607 if (gpiochip->irqdomain) {
1608 for (offset = 0; offset < gpiochip->ngpio; offset++) {
1609 if (!gpiochip_irqchip_irq_valid(gpiochip, offset))
1611 irq_dispose_mapping(
1612 irq_find_mapping(gpiochip->irqdomain, offset));
1614 irq_domain_remove(gpiochip->irqdomain);
1617 if (gpiochip->irqchip) {
1618 gpiochip->irqchip->irq_request_resources = NULL;
1619 gpiochip->irqchip->irq_release_resources = NULL;
1620 gpiochip->irqchip = NULL;
1623 gpiochip_irqchip_free_valid_mask(gpiochip);
1627 * gpiochip_irqchip_add() - adds an irqchip to a gpiochip
1628 * @gpiochip: the gpiochip to add the irqchip to
1629 * @irqchip: the irqchip to add to the gpiochip
1630 * @first_irq: if not dynamically assigned, the base (first) IRQ to
1631 * allocate gpiochip irqs from
1632 * @handler: the irq handler to use (often a predefined irq core function)
1633 * @type: the default type for IRQs on this irqchip, pass IRQ_TYPE_NONE
1634 * to have the core avoid setting up any default type in the hardware.
1635 * @lock_key: lockdep class
1637 * This function closely associates a certain irqchip with a certain
1638 * gpiochip, providing an irq domain to translate the local IRQs to
1639 * global irqs in the gpiolib core, and making sure that the gpiochip
1640 * is passed as chip data to all related functions. Driver callbacks
1641 * need to use gpiochip_get_data() to get their local state containers back
1642 * from the gpiochip passed as chip data. An irqdomain will be stored
1643 * in the gpiochip that shall be used by the driver to handle IRQ number
1644 * translation. The gpiochip will need to be initialized and registered
1645 * before calling this function.
1647 * This function will handle two cell:ed simple IRQs and assumes all
1648 * the pins on the gpiochip can generate a unique IRQ. Everything else
1649 * need to be open coded.
1651 int _gpiochip_irqchip_add(struct gpio_chip *gpiochip,
1652 struct irq_chip *irqchip,
1653 unsigned int first_irq,
1654 irq_flow_handler_t handler,
1656 struct lock_class_key *lock_key)
1658 struct device_node *of_node;
1659 bool irq_base_set = false;
1660 unsigned int offset;
1661 unsigned irq_base = 0;
1663 if (!gpiochip || !irqchip)
1666 if (!gpiochip->parent) {
1667 pr_err("missing gpiochip .dev parent pointer\n");
1670 of_node = gpiochip->parent->of_node;
1671 #ifdef CONFIG_OF_GPIO
1673 * If the gpiochip has an assigned OF node this takes precedence
1674 * FIXME: get rid of this and use gpiochip->parent->of_node
1677 if (gpiochip->of_node)
1678 of_node = gpiochip->of_node;
1681 * Specifying a default trigger is a terrible idea if DT or ACPI is
1682 * used to configure the interrupts, as you may end-up with
1683 * conflicting triggers. Tell the user, and reset to NONE.
1685 if (WARN(of_node && type != IRQ_TYPE_NONE,
1686 "%s: Ignoring %d default trigger\n", of_node->full_name, type))
1687 type = IRQ_TYPE_NONE;
1688 if (has_acpi_companion(gpiochip->parent) && type != IRQ_TYPE_NONE) {
1689 acpi_handle_warn(ACPI_HANDLE(gpiochip->parent),
1690 "Ignoring %d default trigger\n", type);
1691 type = IRQ_TYPE_NONE;
1694 gpiochip->irqchip = irqchip;
1695 gpiochip->irq_handler = handler;
1696 gpiochip->irq_default_type = type;
1697 gpiochip->to_irq = gpiochip_to_irq;
1698 gpiochip->lock_key = lock_key;
1699 gpiochip->irqdomain = irq_domain_add_simple(of_node,
1700 gpiochip->ngpio, first_irq,
1701 &gpiochip_domain_ops, gpiochip);
1702 if (!gpiochip->irqdomain) {
1703 gpiochip->irqchip = NULL;
1708 * It is possible for a driver to override this, but only if the
1709 * alternative functions are both implemented.
1711 if (!irqchip->irq_request_resources &&
1712 !irqchip->irq_release_resources) {
1713 irqchip->irq_request_resources = gpiochip_irq_reqres;
1714 irqchip->irq_release_resources = gpiochip_irq_relres;
1718 * Prepare the mapping since the irqchip shall be orthogonal to
1719 * any gpiochip calls. If the first_irq was zero, this is
1720 * necessary to allocate descriptors for all IRQs.
1722 for (offset = 0; offset < gpiochip->ngpio; offset++) {
1723 if (!gpiochip_irqchip_irq_valid(gpiochip, offset))
1725 irq_base = irq_create_mapping(gpiochip->irqdomain, offset);
1726 if (!irq_base_set) {
1728 * Store the base into the gpiochip to be used when
1729 * unmapping the irqs.
1731 gpiochip->irq_base = irq_base;
1732 irq_base_set = true;
1736 acpi_gpiochip_request_interrupts(gpiochip);
1740 EXPORT_SYMBOL_GPL(_gpiochip_irqchip_add);
1742 #else /* CONFIG_GPIOLIB_IRQCHIP */
1744 static void gpiochip_irqchip_remove(struct gpio_chip *gpiochip) {}
1745 static inline int gpiochip_irqchip_init_valid_mask(struct gpio_chip *gpiochip)
1749 static inline void gpiochip_irqchip_free_valid_mask(struct gpio_chip *gpiochip)
1752 #endif /* CONFIG_GPIOLIB_IRQCHIP */
1755 * gpiochip_generic_request() - request the gpio function for a pin
1756 * @chip: the gpiochip owning the GPIO
1757 * @offset: the offset of the GPIO to request for GPIO function
1759 int gpiochip_generic_request(struct gpio_chip *chip, unsigned offset)
1761 return pinctrl_request_gpio(chip->gpiodev->base + offset);
1763 EXPORT_SYMBOL_GPL(gpiochip_generic_request);
1766 * gpiochip_generic_free() - free the gpio function from a pin
1767 * @chip: the gpiochip to request the gpio function for
1768 * @offset: the offset of the GPIO to free from GPIO function
1770 void gpiochip_generic_free(struct gpio_chip *chip, unsigned offset)
1772 pinctrl_free_gpio(chip->gpiodev->base + offset);
1774 EXPORT_SYMBOL_GPL(gpiochip_generic_free);
1776 #ifdef CONFIG_PINCTRL
1779 * gpiochip_add_pingroup_range() - add a range for GPIO <-> pin mapping
1780 * @chip: the gpiochip to add the range for
1781 * @pctldev: the pin controller to map to
1782 * @gpio_offset: the start offset in the current gpio_chip number space
1783 * @pin_group: name of the pin group inside the pin controller
1785 int gpiochip_add_pingroup_range(struct gpio_chip *chip,
1786 struct pinctrl_dev *pctldev,
1787 unsigned int gpio_offset, const char *pin_group)
1789 struct gpio_pin_range *pin_range;
1790 struct gpio_device *gdev = chip->gpiodev;
1793 pin_range = kzalloc(sizeof(*pin_range), GFP_KERNEL);
1795 chip_err(chip, "failed to allocate pin ranges\n");
1799 /* Use local offset as range ID */
1800 pin_range->range.id = gpio_offset;
1801 pin_range->range.gc = chip;
1802 pin_range->range.name = chip->label;
1803 pin_range->range.base = gdev->base + gpio_offset;
1804 pin_range->pctldev = pctldev;
1806 ret = pinctrl_get_group_pins(pctldev, pin_group,
1807 &pin_range->range.pins,
1808 &pin_range->range.npins);
1814 pinctrl_add_gpio_range(pctldev, &pin_range->range);
1816 chip_dbg(chip, "created GPIO range %d->%d ==> %s PINGRP %s\n",
1817 gpio_offset, gpio_offset + pin_range->range.npins - 1,
1818 pinctrl_dev_get_devname(pctldev), pin_group);
1820 list_add_tail(&pin_range->node, &gdev->pin_ranges);
1824 EXPORT_SYMBOL_GPL(gpiochip_add_pingroup_range);
1827 * gpiochip_add_pin_range() - add a range for GPIO <-> pin mapping
1828 * @chip: the gpiochip to add the range for
1829 * @pinctrl_name: the dev_name() of the pin controller to map to
1830 * @gpio_offset: the start offset in the current gpio_chip number space
1831 * @pin_offset: the start offset in the pin controller number space
1832 * @npins: the number of pins from the offset of each pin space (GPIO and
1833 * pin controller) to accumulate in this range
1835 int gpiochip_add_pin_range(struct gpio_chip *chip, const char *pinctl_name,
1836 unsigned int gpio_offset, unsigned int pin_offset,
1839 struct gpio_pin_range *pin_range;
1840 struct gpio_device *gdev = chip->gpiodev;
1843 pin_range = kzalloc(sizeof(*pin_range), GFP_KERNEL);
1845 chip_err(chip, "failed to allocate pin ranges\n");
1849 /* Use local offset as range ID */
1850 pin_range->range.id = gpio_offset;
1851 pin_range->range.gc = chip;
1852 pin_range->range.name = chip->label;
1853 pin_range->range.base = gdev->base + gpio_offset;
1854 pin_range->range.pin_base = pin_offset;
1855 pin_range->range.npins = npins;
1856 pin_range->pctldev = pinctrl_find_and_add_gpio_range(pinctl_name,
1858 if (IS_ERR(pin_range->pctldev)) {
1859 ret = PTR_ERR(pin_range->pctldev);
1860 chip_err(chip, "could not create pin range\n");
1864 chip_dbg(chip, "created GPIO range %d->%d ==> %s PIN %d->%d\n",
1865 gpio_offset, gpio_offset + npins - 1,
1867 pin_offset, pin_offset + npins - 1);
1869 list_add_tail(&pin_range->node, &gdev->pin_ranges);
1873 EXPORT_SYMBOL_GPL(gpiochip_add_pin_range);
1876 * gpiochip_remove_pin_ranges() - remove all the GPIO <-> pin mappings
1877 * @chip: the chip to remove all the mappings for
1879 void gpiochip_remove_pin_ranges(struct gpio_chip *chip)
1881 struct gpio_pin_range *pin_range, *tmp;
1882 struct gpio_device *gdev = chip->gpiodev;
1884 list_for_each_entry_safe(pin_range, tmp, &gdev->pin_ranges, node) {
1885 list_del(&pin_range->node);
1886 pinctrl_remove_gpio_range(pin_range->pctldev,
1891 EXPORT_SYMBOL_GPL(gpiochip_remove_pin_ranges);
1893 #endif /* CONFIG_PINCTRL */
1895 /* These "optional" allocation calls help prevent drivers from stomping
1896 * on each other, and help provide better diagnostics in debugfs.
1897 * They're called even less than the "set direction" calls.
1899 static int __gpiod_request(struct gpio_desc *desc, const char *label)
1901 struct gpio_chip *chip = desc->gdev->chip;
1903 unsigned long flags;
1905 spin_lock_irqsave(&gpio_lock, flags);
1907 /* NOTE: gpio_request() can be called in early boot,
1908 * before IRQs are enabled, for non-sleeping (SOC) GPIOs.
1911 if (test_and_set_bit(FLAG_REQUESTED, &desc->flags) == 0) {
1912 desc_set_label(desc, label ? : "?");
1919 if (chip->request) {
1920 /* chip->request may sleep */
1921 spin_unlock_irqrestore(&gpio_lock, flags);
1922 status = chip->request(chip, gpio_chip_hwgpio(desc));
1923 spin_lock_irqsave(&gpio_lock, flags);
1926 desc_set_label(desc, NULL);
1927 clear_bit(FLAG_REQUESTED, &desc->flags);
1931 if (chip->get_direction) {
1932 /* chip->get_direction may sleep */
1933 spin_unlock_irqrestore(&gpio_lock, flags);
1934 gpiod_get_direction(desc);
1935 spin_lock_irqsave(&gpio_lock, flags);
1938 spin_unlock_irqrestore(&gpio_lock, flags);
1943 * This descriptor validation needs to be inserted verbatim into each
1944 * function taking a descriptor, so we need to use a preprocessor
1945 * macro to avoid endless duplication. If the desc is NULL it is an
1946 * optional GPIO and calls should just bail out.
1948 #define VALIDATE_DESC(desc) do { \
1951 if (IS_ERR(desc)) { \
1952 pr_warn("%s: invalid GPIO (errorpointer)\n", __func__); \
1953 return PTR_ERR(desc); \
1955 if (!desc->gdev) { \
1956 pr_warn("%s: invalid GPIO (no device)\n", __func__); \
1959 if ( !desc->gdev->chip ) { \
1960 dev_warn(&desc->gdev->dev, \
1961 "%s: backing chip is gone\n", __func__); \
1965 #define VALIDATE_DESC_VOID(desc) do { \
1968 if (IS_ERR(desc)) { \
1969 pr_warn("%s: invalid GPIO (errorpointer)\n", __func__); \
1972 if (!desc->gdev) { \
1973 pr_warn("%s: invalid GPIO (no device)\n", __func__); \
1976 if (!desc->gdev->chip) { \
1977 dev_warn(&desc->gdev->dev, \
1978 "%s: backing chip is gone\n", __func__); \
1983 int gpiod_request(struct gpio_desc *desc, const char *label)
1985 int status = -EPROBE_DEFER;
1986 struct gpio_device *gdev;
1988 VALIDATE_DESC(desc);
1991 if (try_module_get(gdev->owner)) {
1992 status = __gpiod_request(desc, label);
1994 module_put(gdev->owner);
1996 get_device(&gdev->dev);
2000 gpiod_dbg(desc, "%s: status %d\n", __func__, status);
2005 static bool __gpiod_free(struct gpio_desc *desc)
2008 unsigned long flags;
2009 struct gpio_chip *chip;
2013 gpiod_unexport(desc);
2015 spin_lock_irqsave(&gpio_lock, flags);
2017 chip = desc->gdev->chip;
2018 if (chip && test_bit(FLAG_REQUESTED, &desc->flags)) {
2020 spin_unlock_irqrestore(&gpio_lock, flags);
2021 might_sleep_if(chip->can_sleep);
2022 chip->free(chip, gpio_chip_hwgpio(desc));
2023 spin_lock_irqsave(&gpio_lock, flags);
2025 desc_set_label(desc, NULL);
2026 clear_bit(FLAG_ACTIVE_LOW, &desc->flags);
2027 clear_bit(FLAG_REQUESTED, &desc->flags);
2028 clear_bit(FLAG_OPEN_DRAIN, &desc->flags);
2029 clear_bit(FLAG_OPEN_SOURCE, &desc->flags);
2030 clear_bit(FLAG_IS_HOGGED, &desc->flags);
2034 spin_unlock_irqrestore(&gpio_lock, flags);
2038 void gpiod_free(struct gpio_desc *desc)
2040 if (desc && desc->gdev && __gpiod_free(desc)) {
2041 module_put(desc->gdev->owner);
2042 put_device(&desc->gdev->dev);
2044 WARN_ON(extra_checks);
2049 * gpiochip_is_requested - return string iff signal was requested
2050 * @chip: controller managing the signal
2051 * @offset: of signal within controller's 0..(ngpio - 1) range
2053 * Returns NULL if the GPIO is not currently requested, else a string.
2054 * The string returned is the label passed to gpio_request(); if none has been
2055 * passed it is a meaningless, non-NULL constant.
2057 * This function is for use by GPIO controller drivers. The label can
2058 * help with diagnostics, and knowing that the signal is used as a GPIO
2059 * can help avoid accidentally multiplexing it to another controller.
2061 const char *gpiochip_is_requested(struct gpio_chip *chip, unsigned offset)
2063 struct gpio_desc *desc;
2065 if (offset >= chip->ngpio)
2068 desc = &chip->gpiodev->descs[offset];
2070 if (test_bit(FLAG_REQUESTED, &desc->flags) == 0)
2074 EXPORT_SYMBOL_GPL(gpiochip_is_requested);
2077 * gpiochip_request_own_desc - Allow GPIO chip to request its own descriptor
2078 * @desc: GPIO descriptor to request
2079 * @label: label for the GPIO
2081 * Function allows GPIO chip drivers to request and use their own GPIO
2082 * descriptors via gpiolib API. Difference to gpiod_request() is that this
2083 * function will not increase reference count of the GPIO chip module. This
2084 * allows the GPIO chip module to be unloaded as needed (we assume that the
2085 * GPIO chip driver handles freeing the GPIOs it has requested).
2087 struct gpio_desc *gpiochip_request_own_desc(struct gpio_chip *chip, u16 hwnum,
2090 struct gpio_desc *desc = gpiochip_get_desc(chip, hwnum);
2094 chip_err(chip, "failed to get GPIO descriptor\n");
2098 err = __gpiod_request(desc, label);
2100 return ERR_PTR(err);
2104 EXPORT_SYMBOL_GPL(gpiochip_request_own_desc);
2107 * gpiochip_free_own_desc - Free GPIO requested by the chip driver
2108 * @desc: GPIO descriptor to free
2110 * Function frees the given GPIO requested previously with
2111 * gpiochip_request_own_desc().
2113 void gpiochip_free_own_desc(struct gpio_desc *desc)
2118 EXPORT_SYMBOL_GPL(gpiochip_free_own_desc);
2121 * Drivers MUST set GPIO direction before making get/set calls. In
2122 * some cases this is done in early boot, before IRQs are enabled.
2124 * As a rule these aren't called more than once (except for drivers
2125 * using the open-drain emulation idiom) so these are natural places
2126 * to accumulate extra debugging checks. Note that we can't (yet)
2127 * rely on gpio_request() having been called beforehand.
2131 * gpiod_direction_input - set the GPIO direction to input
2132 * @desc: GPIO to set to input
2134 * Set the direction of the passed GPIO to input, such as gpiod_get_value() can
2135 * be called safely on it.
2137 * Return 0 in case of success, else an error code.
2139 int gpiod_direction_input(struct gpio_desc *desc)
2141 struct gpio_chip *chip;
2142 int status = -EINVAL;
2144 VALIDATE_DESC(desc);
2145 chip = desc->gdev->chip;
2147 if (!chip->get || !chip->direction_input) {
2149 "%s: missing get() or direction_input() operations\n",
2154 status = chip->direction_input(chip, gpio_chip_hwgpio(desc));
2156 clear_bit(FLAG_IS_OUT, &desc->flags);
2158 trace_gpio_direction(desc_to_gpio(desc), 1, status);
2162 EXPORT_SYMBOL_GPL(gpiod_direction_input);
2164 static int _gpiod_direction_output_raw(struct gpio_desc *desc, int value)
2166 struct gpio_chip *gc = desc->gdev->chip;
2169 /* GPIOs used for IRQs shall not be set as output */
2170 if (test_bit(FLAG_USED_AS_IRQ, &desc->flags)) {
2172 "%s: tried to set a GPIO tied to an IRQ as output\n",
2177 if (test_bit(FLAG_OPEN_DRAIN, &desc->flags)) {
2178 /* First see if we can enable open drain in hardware */
2179 if (gc->set_single_ended) {
2180 ret = gc->set_single_ended(gc, gpio_chip_hwgpio(desc),
2181 LINE_MODE_OPEN_DRAIN);
2183 goto set_output_value;
2185 /* Emulate open drain by not actively driving the line high */
2187 return gpiod_direction_input(desc);
2189 else if (test_bit(FLAG_OPEN_SOURCE, &desc->flags)) {
2190 if (gc->set_single_ended) {
2191 ret = gc->set_single_ended(gc, gpio_chip_hwgpio(desc),
2192 LINE_MODE_OPEN_SOURCE);
2194 goto set_output_value;
2196 /* Emulate open source by not actively driving the line low */
2198 return gpiod_direction_input(desc);
2200 /* Make sure to disable open drain/source hardware, if any */
2201 if (gc->set_single_ended)
2202 gc->set_single_ended(gc,
2203 gpio_chip_hwgpio(desc),
2204 LINE_MODE_PUSH_PULL);
2208 if (!gc->set || !gc->direction_output) {
2210 "%s: missing set() or direction_output() operations\n",
2215 ret = gc->direction_output(gc, gpio_chip_hwgpio(desc), value);
2217 set_bit(FLAG_IS_OUT, &desc->flags);
2218 trace_gpio_value(desc_to_gpio(desc), 0, value);
2219 trace_gpio_direction(desc_to_gpio(desc), 0, ret);
2224 * gpiod_direction_output_raw - set the GPIO direction to output
2225 * @desc: GPIO to set to output
2226 * @value: initial output value of the GPIO
2228 * Set the direction of the passed GPIO to output, such as gpiod_set_value() can
2229 * be called safely on it. The initial value of the output must be specified
2230 * as raw value on the physical line without regard for the ACTIVE_LOW status.
2232 * Return 0 in case of success, else an error code.
2234 int gpiod_direction_output_raw(struct gpio_desc *desc, int value)
2236 VALIDATE_DESC(desc);
2237 return _gpiod_direction_output_raw(desc, value);
2239 EXPORT_SYMBOL_GPL(gpiod_direction_output_raw);
2242 * gpiod_direction_output - set the GPIO direction to output
2243 * @desc: GPIO to set to output
2244 * @value: initial output value of the GPIO
2246 * Set the direction of the passed GPIO to output, such as gpiod_set_value() can
2247 * be called safely on it. The initial value of the output must be specified
2248 * as the logical value of the GPIO, i.e. taking its ACTIVE_LOW status into
2251 * Return 0 in case of success, else an error code.
2253 int gpiod_direction_output(struct gpio_desc *desc, int value)
2255 VALIDATE_DESC(desc);
2256 if (test_bit(FLAG_ACTIVE_LOW, &desc->flags))
2258 return _gpiod_direction_output_raw(desc, value);
2260 EXPORT_SYMBOL_GPL(gpiod_direction_output);
2263 * gpiod_set_debounce - sets @debounce time for a @gpio
2264 * @gpio: the gpio to set debounce time
2265 * @debounce: debounce time is microseconds
2267 * returns -ENOTSUPP if the controller does not support setting
2270 int gpiod_set_debounce(struct gpio_desc *desc, unsigned debounce)
2272 struct gpio_chip *chip;
2274 VALIDATE_DESC(desc);
2275 chip = desc->gdev->chip;
2276 if (!chip->set || !chip->set_debounce) {
2278 "%s: missing set() or set_debounce() operations\n",
2283 return chip->set_debounce(chip, gpio_chip_hwgpio(desc), debounce);
2285 EXPORT_SYMBOL_GPL(gpiod_set_debounce);
2288 * gpiod_is_active_low - test whether a GPIO is active-low or not
2289 * @desc: the gpio descriptor to test
2291 * Returns 1 if the GPIO is active-low, 0 otherwise.
2293 int gpiod_is_active_low(const struct gpio_desc *desc)
2295 VALIDATE_DESC(desc);
2296 return test_bit(FLAG_ACTIVE_LOW, &desc->flags);
2298 EXPORT_SYMBOL_GPL(gpiod_is_active_low);
2300 /* I/O calls are only valid after configuration completed; the relevant
2301 * "is this a valid GPIO" error checks should already have been done.
2303 * "Get" operations are often inlinable as reading a pin value register,
2304 * and masking the relevant bit in that register.
2306 * When "set" operations are inlinable, they involve writing that mask to
2307 * one register to set a low value, or a different register to set it high.
2308 * Otherwise locking is needed, so there may be little value to inlining.
2310 *------------------------------------------------------------------------
2312 * IMPORTANT!!! The hot paths -- get/set value -- assume that callers
2313 * have requested the GPIO. That can include implicit requesting by
2314 * a direction setting call. Marking a gpio as requested locks its chip
2315 * in memory, guaranteeing that these table lookups need no more locking
2316 * and that gpiochip_remove() will fail.
2318 * REVISIT when debugging, consider adding some instrumentation to ensure
2319 * that the GPIO was actually requested.
2322 static int _gpiod_get_raw_value(const struct gpio_desc *desc)
2324 struct gpio_chip *chip;
2328 chip = desc->gdev->chip;
2329 offset = gpio_chip_hwgpio(desc);
2330 value = chip->get ? chip->get(chip, offset) : -EIO;
2331 value = value < 0 ? value : !!value;
2332 trace_gpio_value(desc_to_gpio(desc), 1, value);
2337 * gpiod_get_raw_value() - return a gpio's raw value
2338 * @desc: gpio whose value will be returned
2340 * Return the GPIO's raw value, i.e. the value of the physical line disregarding
2341 * its ACTIVE_LOW status, or negative errno on failure.
2343 * This function should be called from contexts where we cannot sleep, and will
2344 * complain if the GPIO chip functions potentially sleep.
2346 int gpiod_get_raw_value(const struct gpio_desc *desc)
2348 VALIDATE_DESC(desc);
2349 /* Should be using gpio_get_value_cansleep() */
2350 WARN_ON(desc->gdev->chip->can_sleep);
2351 return _gpiod_get_raw_value(desc);
2353 EXPORT_SYMBOL_GPL(gpiod_get_raw_value);
2356 * gpiod_get_value() - return a gpio's value
2357 * @desc: gpio whose value will be returned
2359 * Return the GPIO's logical value, i.e. taking the ACTIVE_LOW status into
2360 * account, or negative errno on failure.
2362 * This function should be called from contexts where we cannot sleep, and will
2363 * complain if the GPIO chip functions potentially sleep.
2365 int gpiod_get_value(const struct gpio_desc *desc)
2369 VALIDATE_DESC(desc);
2370 /* Should be using gpio_get_value_cansleep() */
2371 WARN_ON(desc->gdev->chip->can_sleep);
2373 value = _gpiod_get_raw_value(desc);
2377 if (test_bit(FLAG_ACTIVE_LOW, &desc->flags))
2382 EXPORT_SYMBOL_GPL(gpiod_get_value);
2385 * _gpio_set_open_drain_value() - Set the open drain gpio's value.
2386 * @desc: gpio descriptor whose state need to be set.
2387 * @value: Non-zero for setting it HIGH otherwise it will set to LOW.
2389 static void _gpio_set_open_drain_value(struct gpio_desc *desc, bool value)
2392 struct gpio_chip *chip = desc->gdev->chip;
2393 int offset = gpio_chip_hwgpio(desc);
2396 err = chip->direction_input(chip, offset);
2398 clear_bit(FLAG_IS_OUT, &desc->flags);
2400 err = chip->direction_output(chip, offset, 0);
2402 set_bit(FLAG_IS_OUT, &desc->flags);
2404 trace_gpio_direction(desc_to_gpio(desc), value, err);
2407 "%s: Error in set_value for open drain err %d\n",
2412 * _gpio_set_open_source_value() - Set the open source gpio's value.
2413 * @desc: gpio descriptor whose state need to be set.
2414 * @value: Non-zero for setting it HIGH otherwise it will set to LOW.
2416 static void _gpio_set_open_source_value(struct gpio_desc *desc, bool value)
2419 struct gpio_chip *chip = desc->gdev->chip;
2420 int offset = gpio_chip_hwgpio(desc);
2423 err = chip->direction_output(chip, offset, 1);
2425 set_bit(FLAG_IS_OUT, &desc->flags);
2427 err = chip->direction_input(chip, offset);
2429 clear_bit(FLAG_IS_OUT, &desc->flags);
2431 trace_gpio_direction(desc_to_gpio(desc), !value, err);
2434 "%s: Error in set_value for open source err %d\n",
2438 static void _gpiod_set_raw_value(struct gpio_desc *desc, bool value)
2440 struct gpio_chip *chip;
2442 chip = desc->gdev->chip;
2443 trace_gpio_value(desc_to_gpio(desc), 0, value);
2444 if (test_bit(FLAG_OPEN_DRAIN, &desc->flags))
2445 _gpio_set_open_drain_value(desc, value);
2446 else if (test_bit(FLAG_OPEN_SOURCE, &desc->flags))
2447 _gpio_set_open_source_value(desc, value);
2449 chip->set(chip, gpio_chip_hwgpio(desc), value);
2453 * set multiple outputs on the same chip;
2454 * use the chip's set_multiple function if available;
2455 * otherwise set the outputs sequentially;
2456 * @mask: bit mask array; one bit per output; BITS_PER_LONG bits per word
2457 * defines which outputs are to be changed
2458 * @bits: bit value array; one bit per output; BITS_PER_LONG bits per word
2459 * defines the values the outputs specified by mask are to be set to
2461 static void gpio_chip_set_multiple(struct gpio_chip *chip,
2462 unsigned long *mask, unsigned long *bits)
2464 if (chip->set_multiple) {
2465 chip->set_multiple(chip, mask, bits);
2468 for (i = 0; i < chip->ngpio; i++) {
2469 if (mask[BIT_WORD(i)] == 0) {
2470 /* no more set bits in this mask word;
2471 * skip ahead to the next word */
2472 i = (BIT_WORD(i) + 1) * BITS_PER_LONG - 1;
2475 /* set outputs if the corresponding mask bit is set */
2476 if (__test_and_clear_bit(i, mask))
2477 chip->set(chip, i, test_bit(i, bits));
2482 void gpiod_set_array_value_complex(bool raw, bool can_sleep,
2483 unsigned int array_size,
2484 struct gpio_desc **desc_array,
2489 while (i < array_size) {
2490 struct gpio_chip *chip = desc_array[i]->gdev->chip;
2491 unsigned long mask[BITS_TO_LONGS(chip->ngpio)];
2492 unsigned long bits[BITS_TO_LONGS(chip->ngpio)];
2496 WARN_ON(chip->can_sleep);
2498 memset(mask, 0, sizeof(mask));
2500 struct gpio_desc *desc = desc_array[i];
2501 int hwgpio = gpio_chip_hwgpio(desc);
2502 int value = value_array[i];
2504 if (!raw && test_bit(FLAG_ACTIVE_LOW, &desc->flags))
2506 trace_gpio_value(desc_to_gpio(desc), 0, value);
2508 * collect all normal outputs belonging to the same chip
2509 * open drain and open source outputs are set individually
2511 if (test_bit(FLAG_OPEN_DRAIN, &desc->flags)) {
2512 _gpio_set_open_drain_value(desc, value);
2513 } else if (test_bit(FLAG_OPEN_SOURCE, &desc->flags)) {
2514 _gpio_set_open_source_value(desc, value);
2516 __set_bit(hwgpio, mask);
2518 __set_bit(hwgpio, bits);
2520 __clear_bit(hwgpio, bits);
2524 } while ((i < array_size) &&
2525 (desc_array[i]->gdev->chip == chip));
2526 /* push collected bits to outputs */
2528 gpio_chip_set_multiple(chip, mask, bits);
2533 * gpiod_set_raw_value() - assign a gpio's raw value
2534 * @desc: gpio whose value will be assigned
2535 * @value: value to assign
2537 * Set the raw value of the GPIO, i.e. the value of its physical line without
2538 * regard for its ACTIVE_LOW status.
2540 * This function should be called from contexts where we cannot sleep, and will
2541 * complain if the GPIO chip functions potentially sleep.
2543 void gpiod_set_raw_value(struct gpio_desc *desc, int value)
2545 VALIDATE_DESC_VOID(desc);
2546 /* Should be using gpiod_set_value_cansleep() */
2547 WARN_ON(desc->gdev->chip->can_sleep);
2548 _gpiod_set_raw_value(desc, value);
2550 EXPORT_SYMBOL_GPL(gpiod_set_raw_value);
2553 * gpiod_set_value() - assign a gpio's value
2554 * @desc: gpio whose value will be assigned
2555 * @value: value to assign
2557 * Set the logical value of the GPIO, i.e. taking its ACTIVE_LOW status into
2560 * This function should be called from contexts where we cannot sleep, and will
2561 * complain if the GPIO chip functions potentially sleep.
2563 void gpiod_set_value(struct gpio_desc *desc, int value)
2565 VALIDATE_DESC_VOID(desc);
2566 /* Should be using gpiod_set_value_cansleep() */
2567 WARN_ON(desc->gdev->chip->can_sleep);
2568 if (test_bit(FLAG_ACTIVE_LOW, &desc->flags))
2570 _gpiod_set_raw_value(desc, value);
2572 EXPORT_SYMBOL_GPL(gpiod_set_value);
2575 * gpiod_set_raw_array_value() - assign values to an array of GPIOs
2576 * @array_size: number of elements in the descriptor / value arrays
2577 * @desc_array: array of GPIO descriptors whose values will be assigned
2578 * @value_array: array of values to assign
2580 * Set the raw values of the GPIOs, i.e. the values of the physical lines
2581 * without regard for their ACTIVE_LOW status.
2583 * This function should be called from contexts where we cannot sleep, and will
2584 * complain if the GPIO chip functions potentially sleep.
2586 void gpiod_set_raw_array_value(unsigned int array_size,
2587 struct gpio_desc **desc_array, int *value_array)
2591 gpiod_set_array_value_complex(true, false, array_size, desc_array,
2594 EXPORT_SYMBOL_GPL(gpiod_set_raw_array_value);
2597 * gpiod_set_array_value() - assign values to an array of GPIOs
2598 * @array_size: number of elements in the descriptor / value arrays
2599 * @desc_array: array of GPIO descriptors whose values will be assigned
2600 * @value_array: array of values to assign
2602 * Set the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status
2605 * This function should be called from contexts where we cannot sleep, and will
2606 * complain if the GPIO chip functions potentially sleep.
2608 void gpiod_set_array_value(unsigned int array_size,
2609 struct gpio_desc **desc_array, int *value_array)
2613 gpiod_set_array_value_complex(false, false, array_size, desc_array,
2616 EXPORT_SYMBOL_GPL(gpiod_set_array_value);
2619 * gpiod_cansleep() - report whether gpio value access may sleep
2620 * @desc: gpio to check
2623 int gpiod_cansleep(const struct gpio_desc *desc)
2625 VALIDATE_DESC(desc);
2626 return desc->gdev->chip->can_sleep;
2628 EXPORT_SYMBOL_GPL(gpiod_cansleep);
2631 * gpiod_to_irq() - return the IRQ corresponding to a GPIO
2632 * @desc: gpio whose IRQ will be returned (already requested)
2634 * Return the IRQ corresponding to the passed GPIO, or an error code in case of
2637 int gpiod_to_irq(const struct gpio_desc *desc)
2639 struct gpio_chip *chip;
2643 * Cannot VALIDATE_DESC() here as gpiod_to_irq() consumer semantics
2644 * requires this function to not return zero on an invalid descriptor
2645 * but rather a negative error number.
2647 if (!desc || IS_ERR(desc) || !desc->gdev || !desc->gdev->chip)
2650 chip = desc->gdev->chip;
2651 offset = gpio_chip_hwgpio(desc);
2653 int retirq = chip->to_irq(chip, offset);
2655 /* Zero means NO_IRQ */
2663 EXPORT_SYMBOL_GPL(gpiod_to_irq);
2666 * gpiochip_lock_as_irq() - lock a GPIO to be used as IRQ
2667 * @chip: the chip the GPIO to lock belongs to
2668 * @offset: the offset of the GPIO to lock as IRQ
2670 * This is used directly by GPIO drivers that want to lock down
2671 * a certain GPIO line to be used for IRQs.
2673 int gpiochip_lock_as_irq(struct gpio_chip *chip, unsigned int offset)
2675 struct gpio_desc *desc;
2677 desc = gpiochip_get_desc(chip, offset);
2679 return PTR_ERR(desc);
2681 /* Flush direction if something changed behind our back */
2682 if (chip->get_direction) {
2683 int dir = chip->get_direction(chip, offset);
2686 clear_bit(FLAG_IS_OUT, &desc->flags);
2688 set_bit(FLAG_IS_OUT, &desc->flags);
2691 if (test_bit(FLAG_IS_OUT, &desc->flags)) {
2693 "%s: tried to flag a GPIO set as output for IRQ\n",
2698 set_bit(FLAG_USED_AS_IRQ, &desc->flags);
2701 EXPORT_SYMBOL_GPL(gpiochip_lock_as_irq);
2704 * gpiochip_unlock_as_irq() - unlock a GPIO used as IRQ
2705 * @chip: the chip the GPIO to lock belongs to
2706 * @offset: the offset of the GPIO to lock as IRQ
2708 * This is used directly by GPIO drivers that want to indicate
2709 * that a certain GPIO is no longer used exclusively for IRQ.
2711 void gpiochip_unlock_as_irq(struct gpio_chip *chip, unsigned int offset)
2713 if (offset >= chip->ngpio)
2716 clear_bit(FLAG_USED_AS_IRQ, &chip->gpiodev->descs[offset].flags);
2718 EXPORT_SYMBOL_GPL(gpiochip_unlock_as_irq);
2720 bool gpiochip_line_is_irq(struct gpio_chip *chip, unsigned int offset)
2722 if (offset >= chip->ngpio)
2725 return test_bit(FLAG_USED_AS_IRQ, &chip->gpiodev->descs[offset].flags);
2727 EXPORT_SYMBOL_GPL(gpiochip_line_is_irq);
2729 bool gpiochip_line_is_open_drain(struct gpio_chip *chip, unsigned int offset)
2731 if (offset >= chip->ngpio)
2734 return test_bit(FLAG_OPEN_DRAIN, &chip->gpiodev->descs[offset].flags);
2736 EXPORT_SYMBOL_GPL(gpiochip_line_is_open_drain);
2738 bool gpiochip_line_is_open_source(struct gpio_chip *chip, unsigned int offset)
2740 if (offset >= chip->ngpio)
2743 return test_bit(FLAG_OPEN_SOURCE, &chip->gpiodev->descs[offset].flags);
2745 EXPORT_SYMBOL_GPL(gpiochip_line_is_open_source);
2748 * gpiod_get_raw_value_cansleep() - return a gpio's raw value
2749 * @desc: gpio whose value will be returned
2751 * Return the GPIO's raw value, i.e. the value of the physical line disregarding
2752 * its ACTIVE_LOW status, or negative errno on failure.
2754 * This function is to be called from contexts that can sleep.
2756 int gpiod_get_raw_value_cansleep(const struct gpio_desc *desc)
2758 might_sleep_if(extra_checks);
2759 VALIDATE_DESC(desc);
2760 return _gpiod_get_raw_value(desc);
2762 EXPORT_SYMBOL_GPL(gpiod_get_raw_value_cansleep);
2765 * gpiod_get_value_cansleep() - return a gpio's value
2766 * @desc: gpio whose value will be returned
2768 * Return the GPIO's logical value, i.e. taking the ACTIVE_LOW status into
2769 * account, or negative errno on failure.
2771 * This function is to be called from contexts that can sleep.
2773 int gpiod_get_value_cansleep(const struct gpio_desc *desc)
2777 might_sleep_if(extra_checks);
2778 VALIDATE_DESC(desc);
2779 value = _gpiod_get_raw_value(desc);
2783 if (test_bit(FLAG_ACTIVE_LOW, &desc->flags))
2788 EXPORT_SYMBOL_GPL(gpiod_get_value_cansleep);
2791 * gpiod_set_raw_value_cansleep() - assign a gpio's raw value
2792 * @desc: gpio whose value will be assigned
2793 * @value: value to assign
2795 * Set the raw value of the GPIO, i.e. the value of its physical line without
2796 * regard for its ACTIVE_LOW status.
2798 * This function is to be called from contexts that can sleep.
2800 void gpiod_set_raw_value_cansleep(struct gpio_desc *desc, int value)
2802 might_sleep_if(extra_checks);
2803 VALIDATE_DESC_VOID(desc);
2804 _gpiod_set_raw_value(desc, value);
2806 EXPORT_SYMBOL_GPL(gpiod_set_raw_value_cansleep);
2809 * gpiod_set_value_cansleep() - assign a gpio's value
2810 * @desc: gpio whose value will be assigned
2811 * @value: value to assign
2813 * Set the logical value of the GPIO, i.e. taking its ACTIVE_LOW status into
2816 * This function is to be called from contexts that can sleep.
2818 void gpiod_set_value_cansleep(struct gpio_desc *desc, int value)
2820 might_sleep_if(extra_checks);
2821 VALIDATE_DESC_VOID(desc);
2822 if (test_bit(FLAG_ACTIVE_LOW, &desc->flags))
2824 _gpiod_set_raw_value(desc, value);
2826 EXPORT_SYMBOL_GPL(gpiod_set_value_cansleep);
2829 * gpiod_set_raw_array_value_cansleep() - assign values to an array of GPIOs
2830 * @array_size: number of elements in the descriptor / value arrays
2831 * @desc_array: array of GPIO descriptors whose values will be assigned
2832 * @value_array: array of values to assign
2834 * Set the raw values of the GPIOs, i.e. the values of the physical lines
2835 * without regard for their ACTIVE_LOW status.
2837 * This function is to be called from contexts that can sleep.
2839 void gpiod_set_raw_array_value_cansleep(unsigned int array_size,
2840 struct gpio_desc **desc_array,
2843 might_sleep_if(extra_checks);
2846 gpiod_set_array_value_complex(true, true, array_size, desc_array,
2849 EXPORT_SYMBOL_GPL(gpiod_set_raw_array_value_cansleep);
2852 * gpiod_set_array_value_cansleep() - assign values to an array of GPIOs
2853 * @array_size: number of elements in the descriptor / value arrays
2854 * @desc_array: array of GPIO descriptors whose values will be assigned
2855 * @value_array: array of values to assign
2857 * Set the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status
2860 * This function is to be called from contexts that can sleep.
2862 void gpiod_set_array_value_cansleep(unsigned int array_size,
2863 struct gpio_desc **desc_array,
2866 might_sleep_if(extra_checks);
2869 gpiod_set_array_value_complex(false, true, array_size, desc_array,
2872 EXPORT_SYMBOL_GPL(gpiod_set_array_value_cansleep);
2875 * gpiod_add_lookup_table() - register GPIO device consumers
2876 * @table: table of consumers to register
2878 void gpiod_add_lookup_table(struct gpiod_lookup_table *table)
2880 mutex_lock(&gpio_lookup_lock);
2882 list_add_tail(&table->list, &gpio_lookup_list);
2884 mutex_unlock(&gpio_lookup_lock);
2888 * gpiod_remove_lookup_table() - unregister GPIO device consumers
2889 * @table: table of consumers to unregister
2891 void gpiod_remove_lookup_table(struct gpiod_lookup_table *table)
2893 mutex_lock(&gpio_lookup_lock);
2895 list_del(&table->list);
2897 mutex_unlock(&gpio_lookup_lock);
2900 static struct gpiod_lookup_table *gpiod_find_lookup_table(struct device *dev)
2902 const char *dev_id = dev ? dev_name(dev) : NULL;
2903 struct gpiod_lookup_table *table;
2905 mutex_lock(&gpio_lookup_lock);
2907 list_for_each_entry(table, &gpio_lookup_list, list) {
2908 if (table->dev_id && dev_id) {
2910 * Valid strings on both ends, must be identical to have
2913 if (!strcmp(table->dev_id, dev_id))
2917 * One of the pointers is NULL, so both must be to have
2920 if (dev_id == table->dev_id)
2927 mutex_unlock(&gpio_lookup_lock);
2931 static struct gpio_desc *gpiod_find(struct device *dev, const char *con_id,
2933 enum gpio_lookup_flags *flags)
2935 struct gpio_desc *desc = ERR_PTR(-ENOENT);
2936 struct gpiod_lookup_table *table;
2937 struct gpiod_lookup *p;
2939 table = gpiod_find_lookup_table(dev);
2943 for (p = &table->table[0]; p->chip_label; p++) {
2944 struct gpio_chip *chip;
2946 /* idx must always match exactly */
2950 /* If the lookup entry has a con_id, require exact match */
2951 if (p->con_id && (!con_id || strcmp(p->con_id, con_id)))
2954 chip = find_chip_by_name(p->chip_label);
2957 dev_err(dev, "cannot find GPIO chip %s\n",
2959 return ERR_PTR(-ENODEV);
2962 if (chip->ngpio <= p->chip_hwnum) {
2964 "requested GPIO %d is out of range [0..%d] for chip %s\n",
2965 idx, chip->ngpio, chip->label);
2966 return ERR_PTR(-EINVAL);
2969 desc = gpiochip_get_desc(chip, p->chip_hwnum);
2978 static int dt_gpio_count(struct device *dev, const char *con_id)
2984 for (i = 0; i < ARRAY_SIZE(gpio_suffixes); i++) {
2986 snprintf(propname, sizeof(propname), "%s-%s",
2987 con_id, gpio_suffixes[i]);
2989 snprintf(propname, sizeof(propname), "%s",
2992 ret = of_gpio_named_count(dev->of_node, propname);
2999 static int platform_gpio_count(struct device *dev, const char *con_id)
3001 struct gpiod_lookup_table *table;
3002 struct gpiod_lookup *p;
3003 unsigned int count = 0;
3005 table = gpiod_find_lookup_table(dev);
3009 for (p = &table->table[0]; p->chip_label; p++) {
3010 if ((con_id && p->con_id && !strcmp(con_id, p->con_id)) ||
3011 (!con_id && !p->con_id))
3021 * gpiod_count - return the number of GPIOs associated with a device / function
3022 * or -ENOENT if no GPIO has been assigned to the requested function
3023 * @dev: GPIO consumer, can be NULL for system-global GPIOs
3024 * @con_id: function within the GPIO consumer
3026 int gpiod_count(struct device *dev, const char *con_id)
3028 int count = -ENOENT;
3030 if (IS_ENABLED(CONFIG_OF) && dev && dev->of_node)
3031 count = dt_gpio_count(dev, con_id);
3032 else if (IS_ENABLED(CONFIG_ACPI) && dev && ACPI_HANDLE(dev))
3033 count = acpi_gpio_count(dev, con_id);
3036 count = platform_gpio_count(dev, con_id);
3040 EXPORT_SYMBOL_GPL(gpiod_count);
3043 * gpiod_get - obtain a GPIO for a given GPIO function
3044 * @dev: GPIO consumer, can be NULL for system-global GPIOs
3045 * @con_id: function within the GPIO consumer
3046 * @flags: optional GPIO initialization flags
3048 * Return the GPIO descriptor corresponding to the function con_id of device
3049 * dev, -ENOENT if no GPIO has been assigned to the requested function, or
3050 * another IS_ERR() code if an error occurred while trying to acquire the GPIO.
3052 struct gpio_desc *__must_check gpiod_get(struct device *dev, const char *con_id,
3053 enum gpiod_flags flags)
3055 return gpiod_get_index(dev, con_id, 0, flags);
3057 EXPORT_SYMBOL_GPL(gpiod_get);
3060 * gpiod_get_optional - obtain an optional GPIO for a given GPIO function
3061 * @dev: GPIO consumer, can be NULL for system-global GPIOs
3062 * @con_id: function within the GPIO consumer
3063 * @flags: optional GPIO initialization flags
3065 * This is equivalent to gpiod_get(), except that when no GPIO was assigned to
3066 * the requested function it will return NULL. This is convenient for drivers
3067 * that need to handle optional GPIOs.
3069 struct gpio_desc *__must_check gpiod_get_optional(struct device *dev,
3071 enum gpiod_flags flags)
3073 return gpiod_get_index_optional(dev, con_id, 0, flags);
3075 EXPORT_SYMBOL_GPL(gpiod_get_optional);
3079 * gpiod_configure_flags - helper function to configure a given GPIO
3080 * @desc: gpio whose value will be assigned
3081 * @con_id: function within the GPIO consumer
3082 * @lflags: gpio_lookup_flags - returned from of_find_gpio() or
3084 * @dflags: gpiod_flags - optional GPIO initialization flags
3086 * Return 0 on success, -ENOENT if no GPIO has been assigned to the
3087 * requested function and/or index, or another IS_ERR() code if an error
3088 * occurred while trying to acquire the GPIO.
3090 static int gpiod_configure_flags(struct gpio_desc *desc, const char *con_id,
3091 unsigned long lflags, enum gpiod_flags dflags)
3095 if (lflags & GPIO_ACTIVE_LOW)
3096 set_bit(FLAG_ACTIVE_LOW, &desc->flags);
3097 if (lflags & GPIO_OPEN_DRAIN)
3098 set_bit(FLAG_OPEN_DRAIN, &desc->flags);
3099 if (lflags & GPIO_OPEN_SOURCE)
3100 set_bit(FLAG_OPEN_SOURCE, &desc->flags);
3102 /* No particular flag request, return here... */
3103 if (!(dflags & GPIOD_FLAGS_BIT_DIR_SET)) {
3104 pr_debug("no flags found for %s\n", con_id);
3109 if (dflags & GPIOD_FLAGS_BIT_DIR_OUT)
3110 status = gpiod_direction_output(desc,
3111 dflags & GPIOD_FLAGS_BIT_DIR_VAL);
3113 status = gpiod_direction_input(desc);
3119 * gpiod_get_index - obtain a GPIO from a multi-index GPIO function
3120 * @dev: GPIO consumer, can be NULL for system-global GPIOs
3121 * @con_id: function within the GPIO consumer
3122 * @idx: index of the GPIO to obtain in the consumer
3123 * @flags: optional GPIO initialization flags
3125 * This variant of gpiod_get() allows to access GPIOs other than the first
3126 * defined one for functions that define several GPIOs.
3128 * Return a valid GPIO descriptor, -ENOENT if no GPIO has been assigned to the
3129 * requested function and/or index, or another IS_ERR() code if an error
3130 * occurred while trying to acquire the GPIO.
3132 struct gpio_desc *__must_check gpiod_get_index(struct device *dev,
3135 enum gpiod_flags flags)
3137 struct gpio_desc *desc = NULL;
3139 enum gpio_lookup_flags lookupflags = 0;
3141 dev_dbg(dev, "GPIO lookup for consumer %s\n", con_id);
3144 /* Using device tree? */
3145 if (IS_ENABLED(CONFIG_OF) && dev->of_node) {
3146 dev_dbg(dev, "using device tree for GPIO lookup\n");
3147 desc = of_find_gpio(dev, con_id, idx, &lookupflags);
3148 } else if (ACPI_COMPANION(dev)) {
3149 dev_dbg(dev, "using ACPI for GPIO lookup\n");
3150 desc = acpi_find_gpio(dev, con_id, idx, flags, &lookupflags);
3155 * Either we are not using DT or ACPI, or their lookup did not return
3156 * a result. In that case, use platform lookup as a fallback.
3158 if (!desc || desc == ERR_PTR(-ENOENT)) {
3159 dev_dbg(dev, "using lookup tables for GPIO lookup\n");
3160 desc = gpiod_find(dev, con_id, idx, &lookupflags);
3164 dev_dbg(dev, "lookup for GPIO %s failed\n", con_id);
3168 status = gpiod_request(desc, con_id);
3170 return ERR_PTR(status);
3172 status = gpiod_configure_flags(desc, con_id, lookupflags, flags);
3174 dev_dbg(dev, "setup of GPIO %s failed\n", con_id);
3176 return ERR_PTR(status);
3181 EXPORT_SYMBOL_GPL(gpiod_get_index);
3184 * fwnode_get_named_gpiod - obtain a GPIO from firmware node
3185 * @fwnode: handle of the firmware node
3186 * @propname: name of the firmware property representing the GPIO
3188 * This function can be used for drivers that get their configuration
3191 * Function properly finds the corresponding GPIO using whatever is the
3192 * underlying firmware interface and then makes sure that the GPIO
3193 * descriptor is requested before it is returned to the caller.
3195 * In case of error an ERR_PTR() is returned.
3197 struct gpio_desc *fwnode_get_named_gpiod(struct fwnode_handle *fwnode,
3198 const char *propname)
3200 struct gpio_desc *desc = ERR_PTR(-ENODEV);
3201 bool active_low = false;
3202 bool single_ended = false;
3206 return ERR_PTR(-EINVAL);
3208 if (is_of_node(fwnode)) {
3209 enum of_gpio_flags flags;
3211 desc = of_get_named_gpiod_flags(to_of_node(fwnode), propname, 0,
3213 if (!IS_ERR(desc)) {
3214 active_low = flags & OF_GPIO_ACTIVE_LOW;
3215 single_ended = flags & OF_GPIO_SINGLE_ENDED;
3217 } else if (is_acpi_node(fwnode)) {
3218 struct acpi_gpio_info info;
3220 desc = acpi_node_get_gpiod(fwnode, propname, 0, &info);
3222 active_low = info.polarity == GPIO_ACTIVE_LOW;
3228 ret = gpiod_request(desc, NULL);
3230 return ERR_PTR(ret);
3233 set_bit(FLAG_ACTIVE_LOW, &desc->flags);
3237 set_bit(FLAG_OPEN_DRAIN, &desc->flags);
3239 set_bit(FLAG_OPEN_SOURCE, &desc->flags);
3244 EXPORT_SYMBOL_GPL(fwnode_get_named_gpiod);
3247 * gpiod_get_index_optional - obtain an optional GPIO from a multi-index GPIO
3249 * @dev: GPIO consumer, can be NULL for system-global GPIOs
3250 * @con_id: function within the GPIO consumer
3251 * @index: index of the GPIO to obtain in the consumer
3252 * @flags: optional GPIO initialization flags
3254 * This is equivalent to gpiod_get_index(), except that when no GPIO with the
3255 * specified index was assigned to the requested function it will return NULL.
3256 * This is convenient for drivers that need to handle optional GPIOs.
3258 struct gpio_desc *__must_check gpiod_get_index_optional(struct device *dev,
3261 enum gpiod_flags flags)
3263 struct gpio_desc *desc;
3265 desc = gpiod_get_index(dev, con_id, index, flags);
3267 if (PTR_ERR(desc) == -ENOENT)
3273 EXPORT_SYMBOL_GPL(gpiod_get_index_optional);
3276 * gpiod_hog - Hog the specified GPIO desc given the provided flags
3277 * @desc: gpio whose value will be assigned
3278 * @name: gpio line name
3279 * @lflags: gpio_lookup_flags - returned from of_find_gpio() or
3281 * @dflags: gpiod_flags - optional GPIO initialization flags
3283 int gpiod_hog(struct gpio_desc *desc, const char *name,
3284 unsigned long lflags, enum gpiod_flags dflags)
3286 struct gpio_chip *chip;
3287 struct gpio_desc *local_desc;
3291 chip = gpiod_to_chip(desc);
3292 hwnum = gpio_chip_hwgpio(desc);
3294 local_desc = gpiochip_request_own_desc(chip, hwnum, name);
3295 if (IS_ERR(local_desc)) {
3296 status = PTR_ERR(local_desc);
3297 pr_err("requesting hog GPIO %s (chip %s, offset %d) failed, %d\n",
3298 name, chip->label, hwnum, status);
3302 status = gpiod_configure_flags(desc, name, lflags, dflags);
3304 pr_err("setup of hog GPIO %s (chip %s, offset %d) failed, %d\n",
3305 name, chip->label, hwnum, status);
3306 gpiochip_free_own_desc(desc);
3310 /* Mark GPIO as hogged so it can be identified and removed later */
3311 set_bit(FLAG_IS_HOGGED, &desc->flags);
3313 pr_info("GPIO line %d (%s) hogged as %s%s\n",
3314 desc_to_gpio(desc), name,
3315 (dflags&GPIOD_FLAGS_BIT_DIR_OUT) ? "output" : "input",
3316 (dflags&GPIOD_FLAGS_BIT_DIR_OUT) ?
3317 (dflags&GPIOD_FLAGS_BIT_DIR_VAL) ? "/high" : "/low":"");
3323 * gpiochip_free_hogs - Scan gpio-controller chip and release GPIO hog
3324 * @chip: gpio chip to act on
3326 * This is only used by of_gpiochip_remove to free hogged gpios
3328 static void gpiochip_free_hogs(struct gpio_chip *chip)
3332 for (id = 0; id < chip->ngpio; id++) {
3333 if (test_bit(FLAG_IS_HOGGED, &chip->gpiodev->descs[id].flags))
3334 gpiochip_free_own_desc(&chip->gpiodev->descs[id]);
3339 * gpiod_get_array - obtain multiple GPIOs from a multi-index GPIO function
3340 * @dev: GPIO consumer, can be NULL for system-global GPIOs
3341 * @con_id: function within the GPIO consumer
3342 * @flags: optional GPIO initialization flags
3344 * This function acquires all the GPIOs defined under a given function.
3346 * Return a struct gpio_descs containing an array of descriptors, -ENOENT if
3347 * no GPIO has been assigned to the requested function, or another IS_ERR()
3348 * code if an error occurred while trying to acquire the GPIOs.
3350 struct gpio_descs *__must_check gpiod_get_array(struct device *dev,
3352 enum gpiod_flags flags)
3354 struct gpio_desc *desc;
3355 struct gpio_descs *descs;
3358 count = gpiod_count(dev, con_id);
3360 return ERR_PTR(count);
3362 descs = kzalloc(sizeof(*descs) + sizeof(descs->desc[0]) * count,
3365 return ERR_PTR(-ENOMEM);
3367 for (descs->ndescs = 0; descs->ndescs < count; ) {
3368 desc = gpiod_get_index(dev, con_id, descs->ndescs, flags);
3370 gpiod_put_array(descs);
3371 return ERR_CAST(desc);
3373 descs->desc[descs->ndescs] = desc;
3378 EXPORT_SYMBOL_GPL(gpiod_get_array);
3381 * gpiod_get_array_optional - obtain multiple GPIOs from a multi-index GPIO
3383 * @dev: GPIO consumer, can be NULL for system-global GPIOs
3384 * @con_id: function within the GPIO consumer
3385 * @flags: optional GPIO initialization flags
3387 * This is equivalent to gpiod_get_array(), except that when no GPIO was
3388 * assigned to the requested function it will return NULL.
3390 struct gpio_descs *__must_check gpiod_get_array_optional(struct device *dev,
3392 enum gpiod_flags flags)
3394 struct gpio_descs *descs;
3396 descs = gpiod_get_array(dev, con_id, flags);
3397 if (IS_ERR(descs) && (PTR_ERR(descs) == -ENOENT))
3402 EXPORT_SYMBOL_GPL(gpiod_get_array_optional);
3405 * gpiod_put - dispose of a GPIO descriptor
3406 * @desc: GPIO descriptor to dispose of
3408 * No descriptor can be used after gpiod_put() has been called on it.
3410 void gpiod_put(struct gpio_desc *desc)
3414 EXPORT_SYMBOL_GPL(gpiod_put);
3417 * gpiod_put_array - dispose of multiple GPIO descriptors
3418 * @descs: struct gpio_descs containing an array of descriptors
3420 void gpiod_put_array(struct gpio_descs *descs)
3424 for (i = 0; i < descs->ndescs; i++)
3425 gpiod_put(descs->desc[i]);
3429 EXPORT_SYMBOL_GPL(gpiod_put_array);
3431 static int __init gpiolib_dev_init(void)
3435 /* Register GPIO sysfs bus */
3436 ret = bus_register(&gpio_bus_type);
3438 pr_err("gpiolib: could not register GPIO bus type\n");
3442 ret = alloc_chrdev_region(&gpio_devt, 0, GPIO_DEV_MAX, "gpiochip");
3444 pr_err("gpiolib: failed to allocate char dev region\n");
3445 bus_unregister(&gpio_bus_type);
3447 gpiolib_initialized = true;
3448 gpiochip_setup_devs();
3452 core_initcall(gpiolib_dev_init);
3454 #ifdef CONFIG_DEBUG_FS
3456 static void gpiolib_dbg_show(struct seq_file *s, struct gpio_device *gdev)
3459 struct gpio_chip *chip = gdev->chip;
3460 unsigned gpio = gdev->base;
3461 struct gpio_desc *gdesc = &gdev->descs[0];
3465 for (i = 0; i < gdev->ngpio; i++, gpio++, gdesc++) {
3466 if (!test_bit(FLAG_REQUESTED, &gdesc->flags)) {
3468 seq_printf(s, " gpio-%-3d (%-20.20s)\n",
3474 gpiod_get_direction(gdesc);
3475 is_out = test_bit(FLAG_IS_OUT, &gdesc->flags);
3476 is_irq = test_bit(FLAG_USED_AS_IRQ, &gdesc->flags);
3477 seq_printf(s, " gpio-%-3d (%-20.20s|%-20.20s) %s %s %s",
3478 gpio, gdesc->name ? gdesc->name : "", gdesc->label,
3479 is_out ? "out" : "in ",
3481 ? (chip->get(chip, i) ? "hi" : "lo")
3483 is_irq ? "IRQ" : " ");
3484 seq_printf(s, "\n");
3488 static void *gpiolib_seq_start(struct seq_file *s, loff_t *pos)
3490 unsigned long flags;
3491 struct gpio_device *gdev = NULL;
3492 loff_t index = *pos;
3496 spin_lock_irqsave(&gpio_lock, flags);
3497 list_for_each_entry(gdev, &gpio_devices, list)
3499 spin_unlock_irqrestore(&gpio_lock, flags);
3502 spin_unlock_irqrestore(&gpio_lock, flags);
3507 static void *gpiolib_seq_next(struct seq_file *s, void *v, loff_t *pos)
3509 unsigned long flags;
3510 struct gpio_device *gdev = v;
3513 spin_lock_irqsave(&gpio_lock, flags);
3514 if (list_is_last(&gdev->list, &gpio_devices))
3517 ret = list_entry(gdev->list.next, struct gpio_device, list);
3518 spin_unlock_irqrestore(&gpio_lock, flags);
3526 static void gpiolib_seq_stop(struct seq_file *s, void *v)
3530 static int gpiolib_seq_show(struct seq_file *s, void *v)
3532 struct gpio_device *gdev = v;
3533 struct gpio_chip *chip = gdev->chip;
3534 struct device *parent;
3537 seq_printf(s, "%s%s: (dangling chip)", (char *)s->private,
3538 dev_name(&gdev->dev));
3542 seq_printf(s, "%s%s: GPIOs %d-%d", (char *)s->private,
3543 dev_name(&gdev->dev),
3544 gdev->base, gdev->base + gdev->ngpio - 1);
3545 parent = chip->parent;
3547 seq_printf(s, ", parent: %s/%s",
3548 parent->bus ? parent->bus->name : "no-bus",
3551 seq_printf(s, ", %s", chip->label);
3552 if (chip->can_sleep)
3553 seq_printf(s, ", can sleep");
3554 seq_printf(s, ":\n");
3557 chip->dbg_show(s, chip);
3559 gpiolib_dbg_show(s, gdev);
3564 static const struct seq_operations gpiolib_seq_ops = {
3565 .start = gpiolib_seq_start,
3566 .next = gpiolib_seq_next,
3567 .stop = gpiolib_seq_stop,
3568 .show = gpiolib_seq_show,
3571 static int gpiolib_open(struct inode *inode, struct file *file)
3573 return seq_open(file, &gpiolib_seq_ops);
3576 static const struct file_operations gpiolib_operations = {
3577 .owner = THIS_MODULE,
3578 .open = gpiolib_open,
3580 .llseek = seq_lseek,
3581 .release = seq_release,
3584 static int __init gpiolib_debugfs_init(void)
3586 /* /sys/kernel/debug/gpio */
3587 (void) debugfs_create_file("gpio", S_IFREG | S_IRUGO,
3588 NULL, NULL, &gpiolib_operations);
3591 subsys_initcall(gpiolib_debugfs_init);
3593 #endif /* DEBUG_FS */