1 #include <linux/bitmap.h>
2 #include <linux/kernel.h>
3 #include <linux/module.h>
4 #include <linux/interrupt.h>
6 #include <linux/spinlock.h>
7 #include <linux/list.h>
8 #include <linux/device.h>
10 #include <linux/debugfs.h>
11 #include <linux/seq_file.h>
12 #include <linux/gpio.h>
13 #include <linux/of_gpio.h>
14 #include <linux/idr.h>
15 #include <linux/slab.h>
16 #include <linux/acpi.h>
17 #include <linux/gpio/driver.h>
18 #include <linux/gpio/machine.h>
19 #include <linux/pinctrl/consumer.h>
20 #include <linux/cdev.h>
22 #include <linux/uaccess.h>
23 #include <linux/compat.h>
24 #include <linux/anon_inodes.h>
25 #include <linux/file.h>
26 #include <linux/kfifo.h>
27 #include <linux/poll.h>
28 #include <linux/timekeeping.h>
29 #include <uapi/linux/gpio.h>
33 #define CREATE_TRACE_POINTS
34 #include <trace/events/gpio.h>
36 /* Implementation infrastructure for GPIO interfaces.
38 * The GPIO programming interface allows for inlining speed-critical
39 * get/set operations for common cases, so that access to SOC-integrated
40 * GPIOs can sometimes cost only an instruction or two per bit.
44 /* When debugging, extend minimal trust to callers and platform code.
45 * Also emit diagnostic messages that may help initial bringup, when
46 * board setup or driver bugs are most common.
48 * Otherwise, minimize overhead in what may be bitbanging codepaths.
51 #define extra_checks 1
53 #define extra_checks 0
56 /* Device and char device-related information */
57 static DEFINE_IDA(gpio_ida
);
58 static dev_t gpio_devt
;
59 #define GPIO_DEV_MAX 256 /* 256 GPIO chip devices supported */
60 static struct bus_type gpio_bus_type
= {
64 /* gpio_lock prevents conflicts during gpio_desc[] table updates.
65 * While any GPIO is requested, its gpio_chip is not removable;
66 * each GPIO's "requested" flag serves as a lock and refcount.
68 DEFINE_SPINLOCK(gpio_lock
);
70 static DEFINE_MUTEX(gpio_lookup_lock
);
71 static LIST_HEAD(gpio_lookup_list
);
72 LIST_HEAD(gpio_devices
);
74 static void gpiochip_free_hogs(struct gpio_chip
*chip
);
75 static int gpiochip_add_irqchip(struct gpio_chip
*gpiochip
,
76 struct lock_class_key
*lock_key
,
77 struct lock_class_key
*request_key
);
78 static void gpiochip_irqchip_remove(struct gpio_chip
*gpiochip
);
79 static int gpiochip_irqchip_init_valid_mask(struct gpio_chip
*gpiochip
);
80 static void gpiochip_irqchip_free_valid_mask(struct gpio_chip
*gpiochip
);
82 static bool gpiolib_initialized
;
84 static inline void desc_set_label(struct gpio_desc
*d
, const char *label
)
90 * gpio_to_desc - Convert a GPIO number to its descriptor
91 * @gpio: global GPIO number
94 * The GPIO descriptor associated with the given GPIO, or %NULL if no GPIO
95 * with the given number exists in the system.
97 struct gpio_desc
*gpio_to_desc(unsigned gpio
)
99 struct gpio_device
*gdev
;
102 spin_lock_irqsave(&gpio_lock
, flags
);
104 list_for_each_entry(gdev
, &gpio_devices
, list
) {
105 if (gdev
->base
<= gpio
&&
106 gdev
->base
+ gdev
->ngpio
> gpio
) {
107 spin_unlock_irqrestore(&gpio_lock
, flags
);
108 return &gdev
->descs
[gpio
- gdev
->base
];
112 spin_unlock_irqrestore(&gpio_lock
, flags
);
114 if (!gpio_is_valid(gpio
))
115 WARN(1, "invalid GPIO %d\n", gpio
);
119 EXPORT_SYMBOL_GPL(gpio_to_desc
);
122 * gpiochip_get_desc - get the GPIO descriptor corresponding to the given
123 * hardware number for this chip
125 * @hwnum: hardware number of the GPIO for this chip
128 * A pointer to the GPIO descriptor or %ERR_PTR(-EINVAL) if no GPIO exists
129 * in the given chip for the specified hardware number.
131 struct gpio_desc
*gpiochip_get_desc(struct gpio_chip
*chip
,
134 struct gpio_device
*gdev
= chip
->gpiodev
;
136 if (hwnum
>= gdev
->ngpio
)
137 return ERR_PTR(-EINVAL
);
139 return &gdev
->descs
[hwnum
];
143 * desc_to_gpio - convert a GPIO descriptor to the integer namespace
144 * @desc: GPIO descriptor
146 * This should disappear in the future but is needed since we still
147 * use GPIO numbers for error messages and sysfs nodes.
150 * The global GPIO number for the GPIO specified by its descriptor.
152 int desc_to_gpio(const struct gpio_desc
*desc
)
154 return desc
->gdev
->base
+ (desc
- &desc
->gdev
->descs
[0]);
156 EXPORT_SYMBOL_GPL(desc_to_gpio
);
160 * gpiod_to_chip - Return the GPIO chip to which a GPIO descriptor belongs
161 * @desc: descriptor to return the chip of
163 struct gpio_chip
*gpiod_to_chip(const struct gpio_desc
*desc
)
165 if (!desc
|| !desc
->gdev
|| !desc
->gdev
->chip
)
167 return desc
->gdev
->chip
;
169 EXPORT_SYMBOL_GPL(gpiod_to_chip
);
171 /* dynamic allocation of GPIOs, e.g. on a hotplugged device */
172 static int gpiochip_find_base(int ngpio
)
174 struct gpio_device
*gdev
;
175 int base
= ARCH_NR_GPIOS
- ngpio
;
177 list_for_each_entry_reverse(gdev
, &gpio_devices
, list
) {
178 /* found a free space? */
179 if (gdev
->base
+ gdev
->ngpio
<= base
)
182 /* nope, check the space right before the chip */
183 base
= gdev
->base
- ngpio
;
186 if (gpio_is_valid(base
)) {
187 pr_debug("%s: found new base at %d\n", __func__
, base
);
190 pr_err("%s: cannot find free range\n", __func__
);
196 * gpiod_get_direction - return the current direction of a GPIO
197 * @desc: GPIO to get the direction of
199 * Return GPIOF_DIR_IN or GPIOF_DIR_OUT, or an error code in case of error.
201 * This function may sleep if gpiod_cansleep() is true.
203 int gpiod_get_direction(struct gpio_desc
*desc
)
205 struct gpio_chip
*chip
;
207 int status
= -EINVAL
;
209 chip
= gpiod_to_chip(desc
);
210 offset
= gpio_chip_hwgpio(desc
);
212 if (!chip
->get_direction
)
215 status
= chip
->get_direction(chip
, offset
);
217 /* GPIOF_DIR_IN, or other positive */
219 clear_bit(FLAG_IS_OUT
, &desc
->flags
);
223 set_bit(FLAG_IS_OUT
, &desc
->flags
);
227 EXPORT_SYMBOL_GPL(gpiod_get_direction
);
230 * Add a new chip to the global chips list, keeping the list of chips sorted
231 * by range(means [base, base + ngpio - 1]) order.
233 * Return -EBUSY if the new chip overlaps with some other chip's integer
236 static int gpiodev_add_to_list(struct gpio_device
*gdev
)
238 struct gpio_device
*prev
, *next
;
240 if (list_empty(&gpio_devices
)) {
241 /* initial entry in list */
242 list_add_tail(&gdev
->list
, &gpio_devices
);
246 next
= list_entry(gpio_devices
.next
, struct gpio_device
, list
);
247 if (gdev
->base
+ gdev
->ngpio
<= next
->base
) {
248 /* add before first entry */
249 list_add(&gdev
->list
, &gpio_devices
);
253 prev
= list_entry(gpio_devices
.prev
, struct gpio_device
, list
);
254 if (prev
->base
+ prev
->ngpio
<= gdev
->base
) {
255 /* add behind last entry */
256 list_add_tail(&gdev
->list
, &gpio_devices
);
260 list_for_each_entry_safe(prev
, next
, &gpio_devices
, list
) {
261 /* at the end of the list */
262 if (&next
->list
== &gpio_devices
)
265 /* add between prev and next */
266 if (prev
->base
+ prev
->ngpio
<= gdev
->base
267 && gdev
->base
+ gdev
->ngpio
<= next
->base
) {
268 list_add(&gdev
->list
, &prev
->list
);
273 dev_err(&gdev
->dev
, "GPIO integer space overlap, cannot add chip\n");
278 * Convert a GPIO name to its descriptor
280 static struct gpio_desc
*gpio_name_to_desc(const char * const name
)
282 struct gpio_device
*gdev
;
285 spin_lock_irqsave(&gpio_lock
, flags
);
287 list_for_each_entry(gdev
, &gpio_devices
, list
) {
290 for (i
= 0; i
!= gdev
->ngpio
; ++i
) {
291 struct gpio_desc
*desc
= &gdev
->descs
[i
];
293 if (!desc
->name
|| !name
)
296 if (!strcmp(desc
->name
, name
)) {
297 spin_unlock_irqrestore(&gpio_lock
, flags
);
303 spin_unlock_irqrestore(&gpio_lock
, flags
);
309 * Takes the names from gc->names and checks if they are all unique. If they
310 * are, they are assigned to their gpio descriptors.
312 * Warning if one of the names is already used for a different GPIO.
314 static int gpiochip_set_desc_names(struct gpio_chip
*gc
)
316 struct gpio_device
*gdev
= gc
->gpiodev
;
322 /* First check all names if they are unique */
323 for (i
= 0; i
!= gc
->ngpio
; ++i
) {
324 struct gpio_desc
*gpio
;
326 gpio
= gpio_name_to_desc(gc
->names
[i
]);
329 "Detected name collision for GPIO name '%s'\n",
333 /* Then add all names to the GPIO descriptors */
334 for (i
= 0; i
!= gc
->ngpio
; ++i
)
335 gdev
->descs
[i
].name
= gc
->names
[i
];
341 * GPIO line handle management
345 * struct linehandle_state - contains the state of a userspace handle
346 * @gdev: the GPIO device the handle pertains to
347 * @label: consumer label used to tag descriptors
348 * @descs: the GPIO descriptors held by this handle
349 * @numdescs: the number of descriptors held in the descs array
351 struct linehandle_state
{
352 struct gpio_device
*gdev
;
354 struct gpio_desc
*descs
[GPIOHANDLES_MAX
];
358 #define GPIOHANDLE_REQUEST_VALID_FLAGS \
359 (GPIOHANDLE_REQUEST_INPUT | \
360 GPIOHANDLE_REQUEST_OUTPUT | \
361 GPIOHANDLE_REQUEST_ACTIVE_LOW | \
362 GPIOHANDLE_REQUEST_OPEN_DRAIN | \
363 GPIOHANDLE_REQUEST_OPEN_SOURCE)
365 static long linehandle_ioctl(struct file
*filep
, unsigned int cmd
,
368 struct linehandle_state
*lh
= filep
->private_data
;
369 void __user
*ip
= (void __user
*)arg
;
370 struct gpiohandle_data ghd
;
371 int vals
[GPIOHANDLES_MAX
];
374 if (cmd
== GPIOHANDLE_GET_LINE_VALUES_IOCTL
) {
375 /* TODO: check if descriptors are really input */
376 int ret
= gpiod_get_array_value_complex(false,
384 memset(&ghd
, 0, sizeof(ghd
));
385 for (i
= 0; i
< lh
->numdescs
; i
++)
386 ghd
.values
[i
] = vals
[i
];
388 if (copy_to_user(ip
, &ghd
, sizeof(ghd
)))
392 } else if (cmd
== GPIOHANDLE_SET_LINE_VALUES_IOCTL
) {
393 /* TODO: check if descriptors are really output */
394 if (copy_from_user(&ghd
, ip
, sizeof(ghd
)))
397 /* Clamp all values to [0,1] */
398 for (i
= 0; i
< lh
->numdescs
; i
++)
399 vals
[i
] = !!ghd
.values
[i
];
401 /* Reuse the array setting function */
402 gpiod_set_array_value_complex(false,
413 static long linehandle_ioctl_compat(struct file
*filep
, unsigned int cmd
,
416 return linehandle_ioctl(filep
, cmd
, (unsigned long)compat_ptr(arg
));
420 static int linehandle_release(struct inode
*inode
, struct file
*filep
)
422 struct linehandle_state
*lh
= filep
->private_data
;
423 struct gpio_device
*gdev
= lh
->gdev
;
426 for (i
= 0; i
< lh
->numdescs
; i
++)
427 gpiod_free(lh
->descs
[i
]);
430 put_device(&gdev
->dev
);
434 static const struct file_operations linehandle_fileops
= {
435 .release
= linehandle_release
,
436 .owner
= THIS_MODULE
,
437 .llseek
= noop_llseek
,
438 .unlocked_ioctl
= linehandle_ioctl
,
440 .compat_ioctl
= linehandle_ioctl_compat
,
444 static int linehandle_create(struct gpio_device
*gdev
, void __user
*ip
)
446 struct gpiohandle_request handlereq
;
447 struct linehandle_state
*lh
;
449 int fd
, i
, count
= 0, ret
;
452 if (copy_from_user(&handlereq
, ip
, sizeof(handlereq
)))
454 if ((handlereq
.lines
== 0) || (handlereq
.lines
> GPIOHANDLES_MAX
))
457 lflags
= handlereq
.flags
;
459 /* Return an error if an unknown flag is set */
460 if (lflags
& ~GPIOHANDLE_REQUEST_VALID_FLAGS
)
464 * Do not allow OPEN_SOURCE & OPEN_DRAIN flags in a single request. If
465 * the hardware actually supports enabling both at the same time the
466 * electrical result would be disastrous.
468 if ((lflags
& GPIOHANDLE_REQUEST_OPEN_DRAIN
) &&
469 (lflags
& GPIOHANDLE_REQUEST_OPEN_SOURCE
))
472 /* OPEN_DRAIN and OPEN_SOURCE flags only make sense for output mode. */
473 if (!(lflags
& GPIOHANDLE_REQUEST_OUTPUT
) &&
474 ((lflags
& GPIOHANDLE_REQUEST_OPEN_DRAIN
) ||
475 (lflags
& GPIOHANDLE_REQUEST_OPEN_SOURCE
)))
478 lh
= kzalloc(sizeof(*lh
), GFP_KERNEL
);
482 get_device(&gdev
->dev
);
484 /* Make sure this is terminated */
485 handlereq
.consumer_label
[sizeof(handlereq
.consumer_label
)-1] = '\0';
486 if (strlen(handlereq
.consumer_label
)) {
487 lh
->label
= kstrdup(handlereq
.consumer_label
,
495 /* Request each GPIO */
496 for (i
= 0; i
< handlereq
.lines
; i
++) {
497 u32 offset
= handlereq
.lineoffsets
[i
];
498 struct gpio_desc
*desc
;
500 if (offset
>= gdev
->ngpio
) {
505 desc
= &gdev
->descs
[offset
];
506 ret
= gpiod_request(desc
, lh
->label
);
512 if (lflags
& GPIOHANDLE_REQUEST_ACTIVE_LOW
)
513 set_bit(FLAG_ACTIVE_LOW
, &desc
->flags
);
514 if (lflags
& GPIOHANDLE_REQUEST_OPEN_DRAIN
)
515 set_bit(FLAG_OPEN_DRAIN
, &desc
->flags
);
516 if (lflags
& GPIOHANDLE_REQUEST_OPEN_SOURCE
)
517 set_bit(FLAG_OPEN_SOURCE
, &desc
->flags
);
520 * Lines have to be requested explicitly for input
521 * or output, else the line will be treated "as is".
523 if (lflags
& GPIOHANDLE_REQUEST_OUTPUT
) {
524 int val
= !!handlereq
.default_values
[i
];
526 ret
= gpiod_direction_output(desc
, val
);
529 } else if (lflags
& GPIOHANDLE_REQUEST_INPUT
) {
530 ret
= gpiod_direction_input(desc
);
534 dev_dbg(&gdev
->dev
, "registered chardev handle for line %d\n",
537 /* Let i point at the last handle */
539 lh
->numdescs
= handlereq
.lines
;
541 fd
= get_unused_fd_flags(O_RDONLY
| O_CLOEXEC
);
547 file
= anon_inode_getfile("gpio-linehandle",
550 O_RDONLY
| O_CLOEXEC
);
553 goto out_put_unused_fd
;
557 if (copy_to_user(ip
, &handlereq
, sizeof(handlereq
))) {
559 * fput() will trigger the release() callback, so do not go onto
560 * the regular error cleanup path here.
567 fd_install(fd
, file
);
569 dev_dbg(&gdev
->dev
, "registered chardev handle for %d lines\n",
577 for (i
= 0; i
< count
; i
++)
578 gpiod_free(lh
->descs
[i
]);
582 put_device(&gdev
->dev
);
587 * GPIO line event management
591 * struct lineevent_state - contains the state of a userspace event
592 * @gdev: the GPIO device the event pertains to
593 * @label: consumer label used to tag descriptors
594 * @desc: the GPIO descriptor held by this event
595 * @eflags: the event flags this line was requested with
596 * @irq: the interrupt that trigger in response to events on this GPIO
597 * @wait: wait queue that handles blocking reads of events
598 * @events: KFIFO for the GPIO events
599 * @read_lock: mutex lock to protect reads from colliding with adding
600 * new events to the FIFO
602 struct lineevent_state
{
603 struct gpio_device
*gdev
;
605 struct gpio_desc
*desc
;
608 wait_queue_head_t wait
;
609 DECLARE_KFIFO(events
, struct gpioevent_data
, 16);
610 struct mutex read_lock
;
613 #define GPIOEVENT_REQUEST_VALID_FLAGS \
614 (GPIOEVENT_REQUEST_RISING_EDGE | \
615 GPIOEVENT_REQUEST_FALLING_EDGE)
617 static unsigned int lineevent_poll(struct file
*filep
,
618 struct poll_table_struct
*wait
)
620 struct lineevent_state
*le
= filep
->private_data
;
621 unsigned int events
= 0;
623 poll_wait(filep
, &le
->wait
, wait
);
625 if (!kfifo_is_empty(&le
->events
))
626 events
= POLLIN
| POLLRDNORM
;
632 static ssize_t
lineevent_read(struct file
*filep
,
637 struct lineevent_state
*le
= filep
->private_data
;
641 if (count
< sizeof(struct gpioevent_data
))
645 if (kfifo_is_empty(&le
->events
)) {
646 if (filep
->f_flags
& O_NONBLOCK
)
649 ret
= wait_event_interruptible(le
->wait
,
650 !kfifo_is_empty(&le
->events
));
655 if (mutex_lock_interruptible(&le
->read_lock
))
657 ret
= kfifo_to_user(&le
->events
, buf
, count
, &copied
);
658 mutex_unlock(&le
->read_lock
);
664 * If we couldn't read anything from the fifo (a different
665 * thread might have been faster) we either return -EAGAIN if
666 * the file descriptor is non-blocking, otherwise we go back to
667 * sleep and wait for more data to arrive.
669 if (copied
== 0 && (filep
->f_flags
& O_NONBLOCK
))
672 } while (copied
== 0);
677 static int lineevent_release(struct inode
*inode
, struct file
*filep
)
679 struct lineevent_state
*le
= filep
->private_data
;
680 struct gpio_device
*gdev
= le
->gdev
;
682 free_irq(le
->irq
, le
);
683 gpiod_free(le
->desc
);
686 put_device(&gdev
->dev
);
690 static long lineevent_ioctl(struct file
*filep
, unsigned int cmd
,
693 struct lineevent_state
*le
= filep
->private_data
;
694 void __user
*ip
= (void __user
*)arg
;
695 struct gpiohandle_data ghd
;
698 * We can get the value for an event line but not set it,
699 * because it is input by definition.
701 if (cmd
== GPIOHANDLE_GET_LINE_VALUES_IOCTL
) {
704 memset(&ghd
, 0, sizeof(ghd
));
706 val
= gpiod_get_value_cansleep(le
->desc
);
711 if (copy_to_user(ip
, &ghd
, sizeof(ghd
)))
720 static long lineevent_ioctl_compat(struct file
*filep
, unsigned int cmd
,
723 return lineevent_ioctl(filep
, cmd
, (unsigned long)compat_ptr(arg
));
727 static const struct file_operations lineevent_fileops
= {
728 .release
= lineevent_release
,
729 .read
= lineevent_read
,
730 .poll
= lineevent_poll
,
731 .owner
= THIS_MODULE
,
732 .llseek
= noop_llseek
,
733 .unlocked_ioctl
= lineevent_ioctl
,
735 .compat_ioctl
= lineevent_ioctl_compat
,
739 static irqreturn_t
lineevent_irq_thread(int irq
, void *p
)
741 struct lineevent_state
*le
= p
;
742 struct gpioevent_data ge
;
745 /* Do not leak kernel stack to userspace */
746 memset(&ge
, 0, sizeof(ge
));
748 ge
.timestamp
= ktime_get_real_ns();
749 level
= gpiod_get_value_cansleep(le
->desc
);
751 if (le
->eflags
& GPIOEVENT_REQUEST_RISING_EDGE
752 && le
->eflags
& GPIOEVENT_REQUEST_FALLING_EDGE
) {
754 /* Emit low-to-high event */
755 ge
.id
= GPIOEVENT_EVENT_RISING_EDGE
;
757 /* Emit high-to-low event */
758 ge
.id
= GPIOEVENT_EVENT_FALLING_EDGE
;
759 } else if (le
->eflags
& GPIOEVENT_REQUEST_RISING_EDGE
&& level
) {
760 /* Emit low-to-high event */
761 ge
.id
= GPIOEVENT_EVENT_RISING_EDGE
;
762 } else if (le
->eflags
& GPIOEVENT_REQUEST_FALLING_EDGE
&& !level
) {
763 /* Emit high-to-low event */
764 ge
.id
= GPIOEVENT_EVENT_FALLING_EDGE
;
769 ret
= kfifo_put(&le
->events
, ge
);
771 wake_up_poll(&le
->wait
, POLLIN
);
776 static int lineevent_create(struct gpio_device
*gdev
, void __user
*ip
)
778 struct gpioevent_request eventreq
;
779 struct lineevent_state
*le
;
780 struct gpio_desc
*desc
;
789 if (copy_from_user(&eventreq
, ip
, sizeof(eventreq
)))
792 le
= kzalloc(sizeof(*le
), GFP_KERNEL
);
796 get_device(&gdev
->dev
);
798 /* Make sure this is terminated */
799 eventreq
.consumer_label
[sizeof(eventreq
.consumer_label
)-1] = '\0';
800 if (strlen(eventreq
.consumer_label
)) {
801 le
->label
= kstrdup(eventreq
.consumer_label
,
809 offset
= eventreq
.lineoffset
;
810 lflags
= eventreq
.handleflags
;
811 eflags
= eventreq
.eventflags
;
813 if (offset
>= gdev
->ngpio
) {
818 /* Return an error if a unknown flag is set */
819 if ((lflags
& ~GPIOHANDLE_REQUEST_VALID_FLAGS
) ||
820 (eflags
& ~GPIOEVENT_REQUEST_VALID_FLAGS
)) {
825 /* This is just wrong: we don't look for events on output lines */
826 if (lflags
& GPIOHANDLE_REQUEST_OUTPUT
) {
831 desc
= &gdev
->descs
[offset
];
832 ret
= gpiod_request(desc
, le
->label
);
838 if (lflags
& GPIOHANDLE_REQUEST_ACTIVE_LOW
)
839 set_bit(FLAG_ACTIVE_LOW
, &desc
->flags
);
840 if (lflags
& GPIOHANDLE_REQUEST_OPEN_DRAIN
)
841 set_bit(FLAG_OPEN_DRAIN
, &desc
->flags
);
842 if (lflags
& GPIOHANDLE_REQUEST_OPEN_SOURCE
)
843 set_bit(FLAG_OPEN_SOURCE
, &desc
->flags
);
845 ret
= gpiod_direction_input(desc
);
849 le
->irq
= gpiod_to_irq(desc
);
855 if (eflags
& GPIOEVENT_REQUEST_RISING_EDGE
)
856 irqflags
|= IRQF_TRIGGER_RISING
;
857 if (eflags
& GPIOEVENT_REQUEST_FALLING_EDGE
)
858 irqflags
|= IRQF_TRIGGER_FALLING
;
859 irqflags
|= IRQF_ONESHOT
;
860 irqflags
|= IRQF_SHARED
;
862 INIT_KFIFO(le
->events
);
863 init_waitqueue_head(&le
->wait
);
864 mutex_init(&le
->read_lock
);
866 /* Request a thread to read the events */
867 ret
= request_threaded_irq(le
->irq
,
869 lineevent_irq_thread
,
876 fd
= get_unused_fd_flags(O_RDONLY
| O_CLOEXEC
);
882 file
= anon_inode_getfile("gpio-event",
885 O_RDONLY
| O_CLOEXEC
);
888 goto out_put_unused_fd
;
892 if (copy_to_user(ip
, &eventreq
, sizeof(eventreq
))) {
894 * fput() will trigger the release() callback, so do not go onto
895 * the regular error cleanup path here.
902 fd_install(fd
, file
);
909 free_irq(le
->irq
, le
);
911 gpiod_free(le
->desc
);
916 put_device(&gdev
->dev
);
921 * gpio_ioctl() - ioctl handler for the GPIO chardev
923 static long gpio_ioctl(struct file
*filp
, unsigned int cmd
, unsigned long arg
)
925 struct gpio_device
*gdev
= filp
->private_data
;
926 struct gpio_chip
*chip
= gdev
->chip
;
927 void __user
*ip
= (void __user
*)arg
;
929 /* We fail any subsequent ioctl():s when the chip is gone */
933 /* Fill in the struct and pass to userspace */
934 if (cmd
== GPIO_GET_CHIPINFO_IOCTL
) {
935 struct gpiochip_info chipinfo
;
937 memset(&chipinfo
, 0, sizeof(chipinfo
));
939 strncpy(chipinfo
.name
, dev_name(&gdev
->dev
),
940 sizeof(chipinfo
.name
));
941 chipinfo
.name
[sizeof(chipinfo
.name
)-1] = '\0';
942 strncpy(chipinfo
.label
, gdev
->label
,
943 sizeof(chipinfo
.label
));
944 chipinfo
.label
[sizeof(chipinfo
.label
)-1] = '\0';
945 chipinfo
.lines
= gdev
->ngpio
;
946 if (copy_to_user(ip
, &chipinfo
, sizeof(chipinfo
)))
949 } else if (cmd
== GPIO_GET_LINEINFO_IOCTL
) {
950 struct gpioline_info lineinfo
;
951 struct gpio_desc
*desc
;
953 if (copy_from_user(&lineinfo
, ip
, sizeof(lineinfo
)))
955 if (lineinfo
.line_offset
>= gdev
->ngpio
)
958 desc
= &gdev
->descs
[lineinfo
.line_offset
];
960 strncpy(lineinfo
.name
, desc
->name
,
961 sizeof(lineinfo
.name
));
962 lineinfo
.name
[sizeof(lineinfo
.name
)-1] = '\0';
964 lineinfo
.name
[0] = '\0';
967 strncpy(lineinfo
.consumer
, desc
->label
,
968 sizeof(lineinfo
.consumer
));
969 lineinfo
.consumer
[sizeof(lineinfo
.consumer
)-1] = '\0';
971 lineinfo
.consumer
[0] = '\0';
975 * Userspace only need to know that the kernel is using
976 * this GPIO so it can't use it.
979 if (test_bit(FLAG_REQUESTED
, &desc
->flags
) ||
980 test_bit(FLAG_IS_HOGGED
, &desc
->flags
) ||
981 test_bit(FLAG_USED_AS_IRQ
, &desc
->flags
) ||
982 test_bit(FLAG_EXPORT
, &desc
->flags
) ||
983 test_bit(FLAG_SYSFS
, &desc
->flags
))
984 lineinfo
.flags
|= GPIOLINE_FLAG_KERNEL
;
985 if (test_bit(FLAG_IS_OUT
, &desc
->flags
))
986 lineinfo
.flags
|= GPIOLINE_FLAG_IS_OUT
;
987 if (test_bit(FLAG_ACTIVE_LOW
, &desc
->flags
))
988 lineinfo
.flags
|= GPIOLINE_FLAG_ACTIVE_LOW
;
989 if (test_bit(FLAG_OPEN_DRAIN
, &desc
->flags
))
990 lineinfo
.flags
|= GPIOLINE_FLAG_OPEN_DRAIN
;
991 if (test_bit(FLAG_OPEN_SOURCE
, &desc
->flags
))
992 lineinfo
.flags
|= GPIOLINE_FLAG_OPEN_SOURCE
;
994 if (copy_to_user(ip
, &lineinfo
, sizeof(lineinfo
)))
997 } else if (cmd
== GPIO_GET_LINEHANDLE_IOCTL
) {
998 return linehandle_create(gdev
, ip
);
999 } else if (cmd
== GPIO_GET_LINEEVENT_IOCTL
) {
1000 return lineevent_create(gdev
, ip
);
1005 #ifdef CONFIG_COMPAT
1006 static long gpio_ioctl_compat(struct file
*filp
, unsigned int cmd
,
1009 return gpio_ioctl(filp
, cmd
, (unsigned long)compat_ptr(arg
));
1014 * gpio_chrdev_open() - open the chardev for ioctl operations
1015 * @inode: inode for this chardev
1016 * @filp: file struct for storing private data
1017 * Returns 0 on success
1019 static int gpio_chrdev_open(struct inode
*inode
, struct file
*filp
)
1021 struct gpio_device
*gdev
= container_of(inode
->i_cdev
,
1022 struct gpio_device
, chrdev
);
1024 /* Fail on open if the backing gpiochip is gone */
1027 get_device(&gdev
->dev
);
1028 filp
->private_data
= gdev
;
1030 return nonseekable_open(inode
, filp
);
1034 * gpio_chrdev_release() - close chardev after ioctl operations
1035 * @inode: inode for this chardev
1036 * @filp: file struct for storing private data
1037 * Returns 0 on success
1039 static int gpio_chrdev_release(struct inode
*inode
, struct file
*filp
)
1041 struct gpio_device
*gdev
= container_of(inode
->i_cdev
,
1042 struct gpio_device
, chrdev
);
1044 put_device(&gdev
->dev
);
1049 static const struct file_operations gpio_fileops
= {
1050 .release
= gpio_chrdev_release
,
1051 .open
= gpio_chrdev_open
,
1052 .owner
= THIS_MODULE
,
1053 .llseek
= no_llseek
,
1054 .unlocked_ioctl
= gpio_ioctl
,
1055 #ifdef CONFIG_COMPAT
1056 .compat_ioctl
= gpio_ioctl_compat
,
1060 static void gpiodevice_release(struct device
*dev
)
1062 struct gpio_device
*gdev
= dev_get_drvdata(dev
);
1064 list_del(&gdev
->list
);
1065 ida_simple_remove(&gpio_ida
, gdev
->id
);
1071 static int gpiochip_setup_dev(struct gpio_device
*gdev
)
1075 cdev_init(&gdev
->chrdev
, &gpio_fileops
);
1076 gdev
->chrdev
.owner
= THIS_MODULE
;
1077 gdev
->dev
.devt
= MKDEV(MAJOR(gpio_devt
), gdev
->id
);
1079 status
= cdev_device_add(&gdev
->chrdev
, &gdev
->dev
);
1083 chip_dbg(gdev
->chip
, "added GPIO chardev (%d:%d)\n",
1084 MAJOR(gpio_devt
), gdev
->id
);
1086 status
= gpiochip_sysfs_register(gdev
);
1088 goto err_remove_device
;
1090 /* From this point, the .release() function cleans up gpio_device */
1091 gdev
->dev
.release
= gpiodevice_release
;
1092 pr_debug("%s: registered GPIOs %d to %d on device: %s (%s)\n",
1093 __func__
, gdev
->base
, gdev
->base
+ gdev
->ngpio
- 1,
1094 dev_name(&gdev
->dev
), gdev
->chip
->label
? : "generic");
1099 cdev_device_del(&gdev
->chrdev
, &gdev
->dev
);
1103 static void gpiochip_setup_devs(void)
1105 struct gpio_device
*gdev
;
1108 list_for_each_entry(gdev
, &gpio_devices
, list
) {
1109 err
= gpiochip_setup_dev(gdev
);
1111 pr_err("%s: Failed to initialize gpio device (%d)\n",
1112 dev_name(&gdev
->dev
), err
);
1116 int gpiochip_add_data_with_key(struct gpio_chip
*chip
, void *data
,
1117 struct lock_class_key
*lock_key
,
1118 struct lock_class_key
*request_key
)
1120 unsigned long flags
;
1123 int base
= chip
->base
;
1124 struct gpio_device
*gdev
;
1127 * First: allocate and populate the internal stat container, and
1128 * set up the struct device.
1130 gdev
= kzalloc(sizeof(*gdev
), GFP_KERNEL
);
1133 gdev
->dev
.bus
= &gpio_bus_type
;
1135 chip
->gpiodev
= gdev
;
1137 gdev
->dev
.parent
= chip
->parent
;
1138 gdev
->dev
.of_node
= chip
->parent
->of_node
;
1141 #ifdef CONFIG_OF_GPIO
1142 /* If the gpiochip has an assigned OF node this takes precedence */
1144 gdev
->dev
.of_node
= chip
->of_node
;
1147 gdev
->id
= ida_simple_get(&gpio_ida
, 0, 0, GFP_KERNEL
);
1152 dev_set_name(&gdev
->dev
, "gpiochip%d", gdev
->id
);
1153 device_initialize(&gdev
->dev
);
1154 dev_set_drvdata(&gdev
->dev
, gdev
);
1155 if (chip
->parent
&& chip
->parent
->driver
)
1156 gdev
->owner
= chip
->parent
->driver
->owner
;
1157 else if (chip
->owner
)
1158 /* TODO: remove chip->owner */
1159 gdev
->owner
= chip
->owner
;
1161 gdev
->owner
= THIS_MODULE
;
1163 gdev
->descs
= kcalloc(chip
->ngpio
, sizeof(gdev
->descs
[0]), GFP_KERNEL
);
1169 if (chip
->ngpio
== 0) {
1170 chip_err(chip
, "tried to insert a GPIO chip with zero lines\n");
1172 goto err_free_descs
;
1176 gdev
->label
= kstrdup(chip
->label
, GFP_KERNEL
);
1178 gdev
->label
= kstrdup("unknown", GFP_KERNEL
);
1181 goto err_free_descs
;
1184 gdev
->ngpio
= chip
->ngpio
;
1187 spin_lock_irqsave(&gpio_lock
, flags
);
1190 * TODO: this allocates a Linux GPIO number base in the global
1191 * GPIO numberspace for this chip. In the long run we want to
1192 * get *rid* of this numberspace and use only descriptors, but
1193 * it may be a pipe dream. It will not happen before we get rid
1194 * of the sysfs interface anyways.
1197 base
= gpiochip_find_base(chip
->ngpio
);
1200 spin_unlock_irqrestore(&gpio_lock
, flags
);
1201 goto err_free_label
;
1204 * TODO: it should not be necessary to reflect the assigned
1205 * base outside of the GPIO subsystem. Go over drivers and
1206 * see if anyone makes use of this, else drop this and assign
1213 status
= gpiodev_add_to_list(gdev
);
1215 spin_unlock_irqrestore(&gpio_lock
, flags
);
1216 goto err_free_label
;
1219 spin_unlock_irqrestore(&gpio_lock
, flags
);
1221 for (i
= 0; i
< chip
->ngpio
; i
++) {
1222 struct gpio_desc
*desc
= &gdev
->descs
[i
];
1226 * REVISIT: most hardware initializes GPIOs as inputs
1227 * (often with pullups enabled) so power usage is
1228 * minimized. Linux code should set the gpio direction
1229 * first thing; but until it does, and in case
1230 * chip->get_direction is not set, we may expose the
1231 * wrong direction in sysfs.
1234 if (chip
->get_direction
) {
1236 * If we have .get_direction, set up the initial
1237 * direction flag from the hardware.
1239 int dir
= chip
->get_direction(chip
, i
);
1242 set_bit(FLAG_IS_OUT
, &desc
->flags
);
1243 } else if (!chip
->direction_input
) {
1245 * If the chip lacks the .direction_input callback
1246 * we logically assume all lines are outputs.
1248 set_bit(FLAG_IS_OUT
, &desc
->flags
);
1252 #ifdef CONFIG_PINCTRL
1253 INIT_LIST_HEAD(&gdev
->pin_ranges
);
1256 status
= gpiochip_set_desc_names(chip
);
1258 goto err_remove_from_list
;
1260 status
= gpiochip_irqchip_init_valid_mask(chip
);
1262 goto err_remove_from_list
;
1264 status
= gpiochip_add_irqchip(chip
, lock_key
, request_key
);
1266 goto err_remove_chip
;
1268 status
= of_gpiochip_add(chip
);
1270 goto err_remove_chip
;
1272 acpi_gpiochip_add(chip
);
1275 * By first adding the chardev, and then adding the device,
1276 * we get a device node entry in sysfs under
1277 * /sys/bus/gpio/devices/gpiochipN/dev that can be used for
1278 * coldplug of device nodes and other udev business.
1279 * We can do this only if gpiolib has been initialized.
1280 * Otherwise, defer until later.
1282 if (gpiolib_initialized
) {
1283 status
= gpiochip_setup_dev(gdev
);
1285 goto err_remove_chip
;
1290 acpi_gpiochip_remove(chip
);
1291 gpiochip_free_hogs(chip
);
1292 of_gpiochip_remove(chip
);
1293 gpiochip_irqchip_free_valid_mask(chip
);
1294 err_remove_from_list
:
1295 spin_lock_irqsave(&gpio_lock
, flags
);
1296 list_del(&gdev
->list
);
1297 spin_unlock_irqrestore(&gpio_lock
, flags
);
1303 ida_simple_remove(&gpio_ida
, gdev
->id
);
1304 /* failures here can mean systems won't boot... */
1305 pr_err("%s: GPIOs %d..%d (%s) failed to register\n", __func__
,
1306 gdev
->base
, gdev
->base
+ gdev
->ngpio
- 1,
1307 chip
->label
? : "generic");
1311 EXPORT_SYMBOL_GPL(gpiochip_add_data_with_key
);
1314 * gpiochip_get_data() - get per-subdriver data for the chip
1318 * The per-subdriver data for the chip.
1320 void *gpiochip_get_data(struct gpio_chip
*chip
)
1322 return chip
->gpiodev
->data
;
1324 EXPORT_SYMBOL_GPL(gpiochip_get_data
);
1327 * gpiochip_remove() - unregister a gpio_chip
1328 * @chip: the chip to unregister
1330 * A gpio_chip with any GPIOs still requested may not be removed.
1332 void gpiochip_remove(struct gpio_chip
*chip
)
1334 struct gpio_device
*gdev
= chip
->gpiodev
;
1335 struct gpio_desc
*desc
;
1336 unsigned long flags
;
1338 bool requested
= false;
1340 /* FIXME: should the legacy sysfs handling be moved to gpio_device? */
1341 gpiochip_sysfs_unregister(gdev
);
1342 gpiochip_free_hogs(chip
);
1343 /* Numb the device, cancelling all outstanding operations */
1345 gpiochip_irqchip_remove(chip
);
1346 acpi_gpiochip_remove(chip
);
1347 gpiochip_remove_pin_ranges(chip
);
1348 of_gpiochip_remove(chip
);
1350 * We accept no more calls into the driver from this point, so
1351 * NULL the driver data pointer
1355 spin_lock_irqsave(&gpio_lock
, flags
);
1356 for (i
= 0; i
< gdev
->ngpio
; i
++) {
1357 desc
= &gdev
->descs
[i
];
1358 if (test_bit(FLAG_REQUESTED
, &desc
->flags
))
1361 spin_unlock_irqrestore(&gpio_lock
, flags
);
1364 dev_crit(&gdev
->dev
,
1365 "REMOVING GPIOCHIP WITH GPIOS STILL REQUESTED\n");
1368 * The gpiochip side puts its use of the device to rest here:
1369 * if there are no userspace clients, the chardev and device will
1370 * be removed, else it will be dangling until the last user is
1373 cdev_device_del(&gdev
->chrdev
, &gdev
->dev
);
1374 put_device(&gdev
->dev
);
1376 EXPORT_SYMBOL_GPL(gpiochip_remove
);
1378 static void devm_gpio_chip_release(struct device
*dev
, void *res
)
1380 struct gpio_chip
*chip
= *(struct gpio_chip
**)res
;
1382 gpiochip_remove(chip
);
1385 static int devm_gpio_chip_match(struct device
*dev
, void *res
, void *data
)
1388 struct gpio_chip
**r
= res
;
1399 * devm_gpiochip_add_data() - Resource manager piochip_add_data()
1400 * @dev: the device pointer on which irq_chip belongs to.
1401 * @chip: the chip to register, with chip->base initialized
1402 * @data: driver-private data associated with this chip
1404 * Context: potentially before irqs will work
1406 * The gpio chip automatically be released when the device is unbound.
1409 * A negative errno if the chip can't be registered, such as because the
1410 * chip->base is invalid or already associated with a different chip.
1411 * Otherwise it returns zero as a success code.
1413 int devm_gpiochip_add_data(struct device
*dev
, struct gpio_chip
*chip
,
1416 struct gpio_chip
**ptr
;
1419 ptr
= devres_alloc(devm_gpio_chip_release
, sizeof(*ptr
),
1424 ret
= gpiochip_add_data(chip
, data
);
1431 devres_add(dev
, ptr
);
1435 EXPORT_SYMBOL_GPL(devm_gpiochip_add_data
);
1438 * devm_gpiochip_remove() - Resource manager of gpiochip_remove()
1439 * @dev: device for which which resource was allocated
1440 * @chip: the chip to remove
1442 * A gpio_chip with any GPIOs still requested may not be removed.
1444 void devm_gpiochip_remove(struct device
*dev
, struct gpio_chip
*chip
)
1448 ret
= devres_release(dev
, devm_gpio_chip_release
,
1449 devm_gpio_chip_match
, chip
);
1452 EXPORT_SYMBOL_GPL(devm_gpiochip_remove
);
1455 * gpiochip_find() - iterator for locating a specific gpio_chip
1456 * @data: data to pass to match function
1457 * @match: Callback function to check gpio_chip
1459 * Similar to bus_find_device. It returns a reference to a gpio_chip as
1460 * determined by a user supplied @match callback. The callback should return
1461 * 0 if the device doesn't match and non-zero if it does. If the callback is
1462 * non-zero, this function will return to the caller and not iterate over any
1465 struct gpio_chip
*gpiochip_find(void *data
,
1466 int (*match
)(struct gpio_chip
*chip
,
1469 struct gpio_device
*gdev
;
1470 struct gpio_chip
*chip
= NULL
;
1471 unsigned long flags
;
1473 spin_lock_irqsave(&gpio_lock
, flags
);
1474 list_for_each_entry(gdev
, &gpio_devices
, list
)
1475 if (gdev
->chip
&& match(gdev
->chip
, data
)) {
1480 spin_unlock_irqrestore(&gpio_lock
, flags
);
1484 EXPORT_SYMBOL_GPL(gpiochip_find
);
1486 static int gpiochip_match_name(struct gpio_chip
*chip
, void *data
)
1488 const char *name
= data
;
1490 return !strcmp(chip
->label
, name
);
1493 static struct gpio_chip
*find_chip_by_name(const char *name
)
1495 return gpiochip_find((void *)name
, gpiochip_match_name
);
1498 #ifdef CONFIG_GPIOLIB_IRQCHIP
1501 * The following is irqchip helper code for gpiochips.
1504 static int gpiochip_irqchip_init_valid_mask(struct gpio_chip
*gpiochip
)
1506 if (!gpiochip
->irq
.need_valid_mask
)
1509 gpiochip
->irq
.valid_mask
= kcalloc(BITS_TO_LONGS(gpiochip
->ngpio
),
1510 sizeof(long), GFP_KERNEL
);
1511 if (!gpiochip
->irq
.valid_mask
)
1514 /* Assume by default all GPIOs are valid */
1515 bitmap_fill(gpiochip
->irq
.valid_mask
, gpiochip
->ngpio
);
1520 static void gpiochip_irqchip_free_valid_mask(struct gpio_chip
*gpiochip
)
1522 kfree(gpiochip
->irq
.valid_mask
);
1523 gpiochip
->irq
.valid_mask
= NULL
;
1526 static bool gpiochip_irqchip_irq_valid(const struct gpio_chip
*gpiochip
,
1527 unsigned int offset
)
1529 /* No mask means all valid */
1530 if (likely(!gpiochip
->irq
.valid_mask
))
1532 return test_bit(offset
, gpiochip
->irq
.valid_mask
);
1536 * gpiochip_set_cascaded_irqchip() - connects a cascaded irqchip to a gpiochip
1537 * @gpiochip: the gpiochip to set the irqchip chain to
1538 * @irqchip: the irqchip to chain to the gpiochip
1539 * @parent_irq: the irq number corresponding to the parent IRQ for this
1541 * @parent_handler: the parent interrupt handler for the accumulated IRQ
1542 * coming out of the gpiochip. If the interrupt is nested rather than
1543 * cascaded, pass NULL in this handler argument
1545 static void gpiochip_set_cascaded_irqchip(struct gpio_chip
*gpiochip
,
1546 struct irq_chip
*irqchip
,
1547 unsigned int parent_irq
,
1548 irq_flow_handler_t parent_handler
)
1550 unsigned int offset
;
1552 if (!gpiochip
->irq
.domain
) {
1553 chip_err(gpiochip
, "called %s before setting up irqchip\n",
1558 if (parent_handler
) {
1559 if (gpiochip
->can_sleep
) {
1561 "you cannot have chained interrupts on a "
1562 "chip that may sleep\n");
1566 * The parent irqchip is already using the chip_data for this
1567 * irqchip, so our callbacks simply use the handler_data.
1569 irq_set_chained_handler_and_data(parent_irq
, parent_handler
,
1572 gpiochip
->irq
.parents
= &parent_irq
;
1573 gpiochip
->irq
.num_parents
= 1;
1576 /* Set the parent IRQ for all affected IRQs */
1577 for (offset
= 0; offset
< gpiochip
->ngpio
; offset
++) {
1578 if (!gpiochip_irqchip_irq_valid(gpiochip
, offset
))
1580 irq_set_parent(irq_find_mapping(gpiochip
->irq
.domain
, offset
),
1586 * gpiochip_set_chained_irqchip() - connects a chained irqchip to a gpiochip
1587 * @gpiochip: the gpiochip to set the irqchip chain to
1588 * @irqchip: the irqchip to chain to the gpiochip
1589 * @parent_irq: the irq number corresponding to the parent IRQ for this
1591 * @parent_handler: the parent interrupt handler for the accumulated IRQ
1592 * coming out of the gpiochip. If the interrupt is nested rather than
1593 * cascaded, pass NULL in this handler argument
1595 void gpiochip_set_chained_irqchip(struct gpio_chip
*gpiochip
,
1596 struct irq_chip
*irqchip
,
1597 unsigned int parent_irq
,
1598 irq_flow_handler_t parent_handler
)
1600 if (gpiochip
->irq
.threaded
) {
1601 chip_err(gpiochip
, "tried to chain a threaded gpiochip\n");
1605 gpiochip_set_cascaded_irqchip(gpiochip
, irqchip
, parent_irq
,
1608 EXPORT_SYMBOL_GPL(gpiochip_set_chained_irqchip
);
1611 * gpiochip_set_nested_irqchip() - connects a nested irqchip to a gpiochip
1612 * @gpiochip: the gpiochip to set the irqchip nested handler to
1613 * @irqchip: the irqchip to nest to the gpiochip
1614 * @parent_irq: the irq number corresponding to the parent IRQ for this
1617 void gpiochip_set_nested_irqchip(struct gpio_chip
*gpiochip
,
1618 struct irq_chip
*irqchip
,
1619 unsigned int parent_irq
)
1621 gpiochip_set_cascaded_irqchip(gpiochip
, irqchip
, parent_irq
,
1624 EXPORT_SYMBOL_GPL(gpiochip_set_nested_irqchip
);
1627 * gpiochip_irq_map() - maps an IRQ into a GPIO irqchip
1628 * @d: the irqdomain used by this irqchip
1629 * @irq: the global irq number used by this GPIO irqchip irq
1630 * @hwirq: the local IRQ/GPIO line offset on this gpiochip
1632 * This function will set up the mapping for a certain IRQ line on a
1633 * gpiochip by assigning the gpiochip as chip data, and using the irqchip
1634 * stored inside the gpiochip.
1636 int gpiochip_irq_map(struct irq_domain
*d
, unsigned int irq
,
1637 irq_hw_number_t hwirq
)
1639 struct gpio_chip
*chip
= d
->host_data
;
1642 if (!gpiochip_irqchip_irq_valid(chip
, hwirq
))
1645 irq_set_chip_data(irq
, chip
);
1647 * This lock class tells lockdep that GPIO irqs are in a different
1648 * category than their parents, so it won't report false recursion.
1650 irq_set_lockdep_class(irq
, chip
->irq
.lock_key
, chip
->irq
.request_key
);
1651 irq_set_chip_and_handler(irq
, chip
->irq
.chip
, chip
->irq
.handler
);
1652 /* Chips that use nested thread handlers have them marked */
1653 if (chip
->irq
.threaded
)
1654 irq_set_nested_thread(irq
, 1);
1655 irq_set_noprobe(irq
);
1657 if (chip
->irq
.num_parents
== 1)
1658 err
= irq_set_parent(irq
, chip
->irq
.parents
[0]);
1659 else if (chip
->irq
.map
)
1660 err
= irq_set_parent(irq
, chip
->irq
.map
[hwirq
]);
1666 * No set-up of the hardware will happen if IRQ_TYPE_NONE
1667 * is passed as default type.
1669 if (chip
->irq
.default_type
!= IRQ_TYPE_NONE
)
1670 irq_set_irq_type(irq
, chip
->irq
.default_type
);
1674 EXPORT_SYMBOL_GPL(gpiochip_irq_map
);
1676 void gpiochip_irq_unmap(struct irq_domain
*d
, unsigned int irq
)
1678 struct gpio_chip
*chip
= d
->host_data
;
1680 if (chip
->irq
.threaded
)
1681 irq_set_nested_thread(irq
, 0);
1682 irq_set_chip_and_handler(irq
, NULL
, NULL
);
1683 irq_set_chip_data(irq
, NULL
);
1685 EXPORT_SYMBOL_GPL(gpiochip_irq_unmap
);
1687 static const struct irq_domain_ops gpiochip_domain_ops
= {
1688 .map
= gpiochip_irq_map
,
1689 .unmap
= gpiochip_irq_unmap
,
1690 /* Virtually all GPIO irqchips are twocell:ed */
1691 .xlate
= irq_domain_xlate_twocell
,
1694 static int gpiochip_irq_reqres(struct irq_data
*d
)
1696 struct gpio_chip
*chip
= irq_data_get_irq_chip_data(d
);
1698 if (!try_module_get(chip
->gpiodev
->owner
))
1701 if (gpiochip_lock_as_irq(chip
, d
->hwirq
)) {
1703 "unable to lock HW IRQ %lu for IRQ\n",
1705 module_put(chip
->gpiodev
->owner
);
1711 static void gpiochip_irq_relres(struct irq_data
*d
)
1713 struct gpio_chip
*chip
= irq_data_get_irq_chip_data(d
);
1715 gpiochip_unlock_as_irq(chip
, d
->hwirq
);
1716 module_put(chip
->gpiodev
->owner
);
1719 static int gpiochip_to_irq(struct gpio_chip
*chip
, unsigned offset
)
1721 if (!gpiochip_irqchip_irq_valid(chip
, offset
))
1724 return irq_create_mapping(chip
->irq
.domain
, offset
);
1728 * gpiochip_add_irqchip() - adds an IRQ chip to a GPIO chip
1729 * @gpiochip: the GPIO chip to add the IRQ chip to
1730 * @lock_key: lockdep class for IRQ lock
1731 * @request_key: lockdep class for IRQ request
1733 static int gpiochip_add_irqchip(struct gpio_chip
*gpiochip
,
1734 struct lock_class_key
*lock_key
,
1735 struct lock_class_key
*request_key
)
1737 struct irq_chip
*irqchip
= gpiochip
->irq
.chip
;
1738 const struct irq_domain_ops
*ops
;
1739 struct device_node
*np
;
1746 if (gpiochip
->irq
.parent_handler
&& gpiochip
->can_sleep
) {
1747 chip_err(gpiochip
, "you cannot have chained interrupts on a "
1748 "chip that may sleep\n");
1752 np
= gpiochip
->gpiodev
->dev
.of_node
;
1753 type
= gpiochip
->irq
.default_type
;
1756 * Specifying a default trigger is a terrible idea if DT or ACPI is
1757 * used to configure the interrupts, as you may end up with
1758 * conflicting triggers. Tell the user, and reset to NONE.
1760 if (WARN(np
&& type
!= IRQ_TYPE_NONE
,
1761 "%s: Ignoring %u default trigger\n", np
->full_name
, type
))
1762 type
= IRQ_TYPE_NONE
;
1764 if (has_acpi_companion(gpiochip
->parent
) && type
!= IRQ_TYPE_NONE
) {
1765 acpi_handle_warn(ACPI_HANDLE(gpiochip
->parent
),
1766 "Ignoring %u default trigger\n", type
);
1767 type
= IRQ_TYPE_NONE
;
1770 gpiochip
->to_irq
= gpiochip_to_irq
;
1771 gpiochip
->irq
.default_type
= type
;
1772 gpiochip
->irq
.lock_key
= lock_key
;
1773 gpiochip
->irq
.request_key
= request_key
;
1775 if (gpiochip
->irq
.domain_ops
)
1776 ops
= gpiochip
->irq
.domain_ops
;
1778 ops
= &gpiochip_domain_ops
;
1780 gpiochip
->irq
.domain
= irq_domain_add_simple(np
, gpiochip
->ngpio
,
1781 gpiochip
->irq
.first
,
1783 if (!gpiochip
->irq
.domain
)
1787 * It is possible for a driver to override this, but only if the
1788 * alternative functions are both implemented.
1790 if (!irqchip
->irq_request_resources
&&
1791 !irqchip
->irq_release_resources
) {
1792 irqchip
->irq_request_resources
= gpiochip_irq_reqres
;
1793 irqchip
->irq_release_resources
= gpiochip_irq_relres
;
1796 if (gpiochip
->irq
.parent_handler
) {
1797 void *data
= gpiochip
->irq
.parent_handler_data
?: gpiochip
;
1799 for (i
= 0; i
< gpiochip
->irq
.num_parents
; i
++) {
1801 * The parent IRQ chip is already using the chip_data
1802 * for this IRQ chip, so our callbacks simply use the
1805 irq_set_chained_handler_and_data(gpiochip
->irq
.parents
[i
],
1806 gpiochip
->irq
.parent_handler
,
1811 acpi_gpiochip_request_interrupts(gpiochip
);
1817 * gpiochip_irqchip_remove() - removes an irqchip added to a gpiochip
1818 * @gpiochip: the gpiochip to remove the irqchip from
1820 * This is called only from gpiochip_remove()
1822 static void gpiochip_irqchip_remove(struct gpio_chip
*gpiochip
)
1824 unsigned int offset
;
1826 acpi_gpiochip_free_interrupts(gpiochip
);
1828 if (gpiochip
->irq
.chip
&& gpiochip
->irq
.parent_handler
) {
1829 struct gpio_irq_chip
*irq
= &gpiochip
->irq
;
1832 for (i
= 0; i
< irq
->num_parents
; i
++)
1833 irq_set_chained_handler_and_data(irq
->parents
[i
],
1837 /* Remove all IRQ mappings and delete the domain */
1838 if (gpiochip
->irq
.domain
) {
1841 for (offset
= 0; offset
< gpiochip
->ngpio
; offset
++) {
1842 if (!gpiochip_irqchip_irq_valid(gpiochip
, offset
))
1845 irq
= irq_find_mapping(gpiochip
->irq
.domain
, offset
);
1846 irq_dispose_mapping(irq
);
1849 irq_domain_remove(gpiochip
->irq
.domain
);
1852 if (gpiochip
->irq
.chip
) {
1853 gpiochip
->irq
.chip
->irq_request_resources
= NULL
;
1854 gpiochip
->irq
.chip
->irq_release_resources
= NULL
;
1855 gpiochip
->irq
.chip
= NULL
;
1858 gpiochip_irqchip_free_valid_mask(gpiochip
);
1862 * gpiochip_irqchip_add_key() - adds an irqchip to a gpiochip
1863 * @gpiochip: the gpiochip to add the irqchip to
1864 * @irqchip: the irqchip to add to the gpiochip
1865 * @first_irq: if not dynamically assigned, the base (first) IRQ to
1866 * allocate gpiochip irqs from
1867 * @handler: the irq handler to use (often a predefined irq core function)
1868 * @type: the default type for IRQs on this irqchip, pass IRQ_TYPE_NONE
1869 * to have the core avoid setting up any default type in the hardware.
1870 * @threaded: whether this irqchip uses a nested thread handler
1871 * @lock_key: lockdep class for IRQ lock
1872 * @request_key: lockdep class for IRQ request
1874 * This function closely associates a certain irqchip with a certain
1875 * gpiochip, providing an irq domain to translate the local IRQs to
1876 * global irqs in the gpiolib core, and making sure that the gpiochip
1877 * is passed as chip data to all related functions. Driver callbacks
1878 * need to use gpiochip_get_data() to get their local state containers back
1879 * from the gpiochip passed as chip data. An irqdomain will be stored
1880 * in the gpiochip that shall be used by the driver to handle IRQ number
1881 * translation. The gpiochip will need to be initialized and registered
1882 * before calling this function.
1884 * This function will handle two cell:ed simple IRQs and assumes all
1885 * the pins on the gpiochip can generate a unique IRQ. Everything else
1886 * need to be open coded.
1888 int gpiochip_irqchip_add_key(struct gpio_chip
*gpiochip
,
1889 struct irq_chip
*irqchip
,
1890 unsigned int first_irq
,
1891 irq_flow_handler_t handler
,
1894 struct lock_class_key
*lock_key
,
1895 struct lock_class_key
*request_key
)
1897 struct device_node
*of_node
;
1899 if (!gpiochip
|| !irqchip
)
1902 if (!gpiochip
->parent
) {
1903 pr_err("missing gpiochip .dev parent pointer\n");
1906 gpiochip
->irq
.threaded
= threaded
;
1907 of_node
= gpiochip
->parent
->of_node
;
1908 #ifdef CONFIG_OF_GPIO
1910 * If the gpiochip has an assigned OF node this takes precedence
1911 * FIXME: get rid of this and use gpiochip->parent->of_node
1914 if (gpiochip
->of_node
)
1915 of_node
= gpiochip
->of_node
;
1918 * Specifying a default trigger is a terrible idea if DT or ACPI is
1919 * used to configure the interrupts, as you may end-up with
1920 * conflicting triggers. Tell the user, and reset to NONE.
1922 if (WARN(of_node
&& type
!= IRQ_TYPE_NONE
,
1923 "%pOF: Ignoring %d default trigger\n", of_node
, type
))
1924 type
= IRQ_TYPE_NONE
;
1925 if (has_acpi_companion(gpiochip
->parent
) && type
!= IRQ_TYPE_NONE
) {
1926 acpi_handle_warn(ACPI_HANDLE(gpiochip
->parent
),
1927 "Ignoring %d default trigger\n", type
);
1928 type
= IRQ_TYPE_NONE
;
1931 gpiochip
->irq
.chip
= irqchip
;
1932 gpiochip
->irq
.handler
= handler
;
1933 gpiochip
->irq
.default_type
= type
;
1934 gpiochip
->to_irq
= gpiochip_to_irq
;
1935 gpiochip
->irq
.lock_key
= lock_key
;
1936 gpiochip
->irq
.request_key
= request_key
;
1937 gpiochip
->irq
.domain
= irq_domain_add_simple(of_node
,
1938 gpiochip
->ngpio
, first_irq
,
1939 &gpiochip_domain_ops
, gpiochip
);
1940 if (!gpiochip
->irq
.domain
) {
1941 gpiochip
->irq
.chip
= NULL
;
1946 * It is possible for a driver to override this, but only if the
1947 * alternative functions are both implemented.
1949 if (!irqchip
->irq_request_resources
&&
1950 !irqchip
->irq_release_resources
) {
1951 irqchip
->irq_request_resources
= gpiochip_irq_reqres
;
1952 irqchip
->irq_release_resources
= gpiochip_irq_relres
;
1955 acpi_gpiochip_request_interrupts(gpiochip
);
1959 EXPORT_SYMBOL_GPL(gpiochip_irqchip_add_key
);
1961 #else /* CONFIG_GPIOLIB_IRQCHIP */
1963 static inline int gpiochip_add_irqchip(struct gpio_chip
*gpiochip
,
1964 struct lock_class_key
*lock_key
,
1965 struct lock_class_key
*request_key
)
1970 static void gpiochip_irqchip_remove(struct gpio_chip
*gpiochip
) {}
1971 static inline int gpiochip_irqchip_init_valid_mask(struct gpio_chip
*gpiochip
)
1975 static inline void gpiochip_irqchip_free_valid_mask(struct gpio_chip
*gpiochip
)
1978 #endif /* CONFIG_GPIOLIB_IRQCHIP */
1981 * gpiochip_generic_request() - request the gpio function for a pin
1982 * @chip: the gpiochip owning the GPIO
1983 * @offset: the offset of the GPIO to request for GPIO function
1985 int gpiochip_generic_request(struct gpio_chip
*chip
, unsigned offset
)
1987 return pinctrl_gpio_request(chip
->gpiodev
->base
+ offset
);
1989 EXPORT_SYMBOL_GPL(gpiochip_generic_request
);
1992 * gpiochip_generic_free() - free the gpio function from a pin
1993 * @chip: the gpiochip to request the gpio function for
1994 * @offset: the offset of the GPIO to free from GPIO function
1996 void gpiochip_generic_free(struct gpio_chip
*chip
, unsigned offset
)
1998 pinctrl_gpio_free(chip
->gpiodev
->base
+ offset
);
2000 EXPORT_SYMBOL_GPL(gpiochip_generic_free
);
2003 * gpiochip_generic_config() - apply configuration for a pin
2004 * @chip: the gpiochip owning the GPIO
2005 * @offset: the offset of the GPIO to apply the configuration
2006 * @config: the configuration to be applied
2008 int gpiochip_generic_config(struct gpio_chip
*chip
, unsigned offset
,
2009 unsigned long config
)
2011 return pinctrl_gpio_set_config(chip
->gpiodev
->base
+ offset
, config
);
2013 EXPORT_SYMBOL_GPL(gpiochip_generic_config
);
2015 #ifdef CONFIG_PINCTRL
2018 * gpiochip_add_pingroup_range() - add a range for GPIO <-> pin mapping
2019 * @chip: the gpiochip to add the range for
2020 * @pctldev: the pin controller to map to
2021 * @gpio_offset: the start offset in the current gpio_chip number space
2022 * @pin_group: name of the pin group inside the pin controller
2024 int gpiochip_add_pingroup_range(struct gpio_chip
*chip
,
2025 struct pinctrl_dev
*pctldev
,
2026 unsigned int gpio_offset
, const char *pin_group
)
2028 struct gpio_pin_range
*pin_range
;
2029 struct gpio_device
*gdev
= chip
->gpiodev
;
2032 pin_range
= kzalloc(sizeof(*pin_range
), GFP_KERNEL
);
2034 chip_err(chip
, "failed to allocate pin ranges\n");
2038 /* Use local offset as range ID */
2039 pin_range
->range
.id
= gpio_offset
;
2040 pin_range
->range
.gc
= chip
;
2041 pin_range
->range
.name
= chip
->label
;
2042 pin_range
->range
.base
= gdev
->base
+ gpio_offset
;
2043 pin_range
->pctldev
= pctldev
;
2045 ret
= pinctrl_get_group_pins(pctldev
, pin_group
,
2046 &pin_range
->range
.pins
,
2047 &pin_range
->range
.npins
);
2053 pinctrl_add_gpio_range(pctldev
, &pin_range
->range
);
2055 chip_dbg(chip
, "created GPIO range %d->%d ==> %s PINGRP %s\n",
2056 gpio_offset
, gpio_offset
+ pin_range
->range
.npins
- 1,
2057 pinctrl_dev_get_devname(pctldev
), pin_group
);
2059 list_add_tail(&pin_range
->node
, &gdev
->pin_ranges
);
2063 EXPORT_SYMBOL_GPL(gpiochip_add_pingroup_range
);
2066 * gpiochip_add_pin_range() - add a range for GPIO <-> pin mapping
2067 * @chip: the gpiochip to add the range for
2068 * @pinctl_name: the dev_name() of the pin controller to map to
2069 * @gpio_offset: the start offset in the current gpio_chip number space
2070 * @pin_offset: the start offset in the pin controller number space
2071 * @npins: the number of pins from the offset of each pin space (GPIO and
2072 * pin controller) to accumulate in this range
2075 * 0 on success, or a negative error-code on failure.
2077 int gpiochip_add_pin_range(struct gpio_chip
*chip
, const char *pinctl_name
,
2078 unsigned int gpio_offset
, unsigned int pin_offset
,
2081 struct gpio_pin_range
*pin_range
;
2082 struct gpio_device
*gdev
= chip
->gpiodev
;
2085 pin_range
= kzalloc(sizeof(*pin_range
), GFP_KERNEL
);
2087 chip_err(chip
, "failed to allocate pin ranges\n");
2091 /* Use local offset as range ID */
2092 pin_range
->range
.id
= gpio_offset
;
2093 pin_range
->range
.gc
= chip
;
2094 pin_range
->range
.name
= chip
->label
;
2095 pin_range
->range
.base
= gdev
->base
+ gpio_offset
;
2096 pin_range
->range
.pin_base
= pin_offset
;
2097 pin_range
->range
.npins
= npins
;
2098 pin_range
->pctldev
= pinctrl_find_and_add_gpio_range(pinctl_name
,
2100 if (IS_ERR(pin_range
->pctldev
)) {
2101 ret
= PTR_ERR(pin_range
->pctldev
);
2102 chip_err(chip
, "could not create pin range\n");
2106 chip_dbg(chip
, "created GPIO range %d->%d ==> %s PIN %d->%d\n",
2107 gpio_offset
, gpio_offset
+ npins
- 1,
2109 pin_offset
, pin_offset
+ npins
- 1);
2111 list_add_tail(&pin_range
->node
, &gdev
->pin_ranges
);
2115 EXPORT_SYMBOL_GPL(gpiochip_add_pin_range
);
2118 * gpiochip_remove_pin_ranges() - remove all the GPIO <-> pin mappings
2119 * @chip: the chip to remove all the mappings for
2121 void gpiochip_remove_pin_ranges(struct gpio_chip
*chip
)
2123 struct gpio_pin_range
*pin_range
, *tmp
;
2124 struct gpio_device
*gdev
= chip
->gpiodev
;
2126 list_for_each_entry_safe(pin_range
, tmp
, &gdev
->pin_ranges
, node
) {
2127 list_del(&pin_range
->node
);
2128 pinctrl_remove_gpio_range(pin_range
->pctldev
,
2133 EXPORT_SYMBOL_GPL(gpiochip_remove_pin_ranges
);
2135 #endif /* CONFIG_PINCTRL */
2137 /* These "optional" allocation calls help prevent drivers from stomping
2138 * on each other, and help provide better diagnostics in debugfs.
2139 * They're called even less than the "set direction" calls.
2141 static int gpiod_request_commit(struct gpio_desc
*desc
, const char *label
)
2143 struct gpio_chip
*chip
= desc
->gdev
->chip
;
2145 unsigned long flags
;
2147 spin_lock_irqsave(&gpio_lock
, flags
);
2149 /* NOTE: gpio_request() can be called in early boot,
2150 * before IRQs are enabled, for non-sleeping (SOC) GPIOs.
2153 if (test_and_set_bit(FLAG_REQUESTED
, &desc
->flags
) == 0) {
2154 desc_set_label(desc
, label
? : "?");
2161 if (chip
->request
) {
2162 /* chip->request may sleep */
2163 spin_unlock_irqrestore(&gpio_lock
, flags
);
2164 status
= chip
->request(chip
, gpio_chip_hwgpio(desc
));
2165 spin_lock_irqsave(&gpio_lock
, flags
);
2168 desc_set_label(desc
, NULL
);
2169 clear_bit(FLAG_REQUESTED
, &desc
->flags
);
2173 if (chip
->get_direction
) {
2174 /* chip->get_direction may sleep */
2175 spin_unlock_irqrestore(&gpio_lock
, flags
);
2176 gpiod_get_direction(desc
);
2177 spin_lock_irqsave(&gpio_lock
, flags
);
2180 spin_unlock_irqrestore(&gpio_lock
, flags
);
2185 * This descriptor validation needs to be inserted verbatim into each
2186 * function taking a descriptor, so we need to use a preprocessor
2187 * macro to avoid endless duplication. If the desc is NULL it is an
2188 * optional GPIO and calls should just bail out.
2190 #define VALIDATE_DESC(desc) do { \
2193 if (IS_ERR(desc)) { \
2194 pr_warn("%s: invalid GPIO (errorpointer)\n", __func__); \
2195 return PTR_ERR(desc); \
2197 if (!desc->gdev) { \
2198 pr_warn("%s: invalid GPIO (no device)\n", __func__); \
2201 if ( !desc->gdev->chip ) { \
2202 dev_warn(&desc->gdev->dev, \
2203 "%s: backing chip is gone\n", __func__); \
2207 #define VALIDATE_DESC_VOID(desc) do { \
2210 if (IS_ERR(desc)) { \
2211 pr_warn("%s: invalid GPIO (errorpointer)\n", __func__); \
2214 if (!desc->gdev) { \
2215 pr_warn("%s: invalid GPIO (no device)\n", __func__); \
2218 if (!desc->gdev->chip) { \
2219 dev_warn(&desc->gdev->dev, \
2220 "%s: backing chip is gone\n", __func__); \
2225 int gpiod_request(struct gpio_desc
*desc
, const char *label
)
2227 int status
= -EPROBE_DEFER
;
2228 struct gpio_device
*gdev
;
2230 VALIDATE_DESC(desc
);
2233 if (try_module_get(gdev
->owner
)) {
2234 status
= gpiod_request_commit(desc
, label
);
2236 module_put(gdev
->owner
);
2238 get_device(&gdev
->dev
);
2242 gpiod_dbg(desc
, "%s: status %d\n", __func__
, status
);
2247 static bool gpiod_free_commit(struct gpio_desc
*desc
)
2250 unsigned long flags
;
2251 struct gpio_chip
*chip
;
2255 gpiod_unexport(desc
);
2257 spin_lock_irqsave(&gpio_lock
, flags
);
2259 chip
= desc
->gdev
->chip
;
2260 if (chip
&& test_bit(FLAG_REQUESTED
, &desc
->flags
)) {
2262 spin_unlock_irqrestore(&gpio_lock
, flags
);
2263 might_sleep_if(chip
->can_sleep
);
2264 chip
->free(chip
, gpio_chip_hwgpio(desc
));
2265 spin_lock_irqsave(&gpio_lock
, flags
);
2267 desc_set_label(desc
, NULL
);
2268 clear_bit(FLAG_ACTIVE_LOW
, &desc
->flags
);
2269 clear_bit(FLAG_REQUESTED
, &desc
->flags
);
2270 clear_bit(FLAG_OPEN_DRAIN
, &desc
->flags
);
2271 clear_bit(FLAG_OPEN_SOURCE
, &desc
->flags
);
2272 clear_bit(FLAG_IS_HOGGED
, &desc
->flags
);
2276 spin_unlock_irqrestore(&gpio_lock
, flags
);
2280 void gpiod_free(struct gpio_desc
*desc
)
2282 if (desc
&& desc
->gdev
&& gpiod_free_commit(desc
)) {
2283 module_put(desc
->gdev
->owner
);
2284 put_device(&desc
->gdev
->dev
);
2286 WARN_ON(extra_checks
);
2291 * gpiochip_is_requested - return string iff signal was requested
2292 * @chip: controller managing the signal
2293 * @offset: of signal within controller's 0..(ngpio - 1) range
2295 * Returns NULL if the GPIO is not currently requested, else a string.
2296 * The string returned is the label passed to gpio_request(); if none has been
2297 * passed it is a meaningless, non-NULL constant.
2299 * This function is for use by GPIO controller drivers. The label can
2300 * help with diagnostics, and knowing that the signal is used as a GPIO
2301 * can help avoid accidentally multiplexing it to another controller.
2303 const char *gpiochip_is_requested(struct gpio_chip
*chip
, unsigned offset
)
2305 struct gpio_desc
*desc
;
2307 if (offset
>= chip
->ngpio
)
2310 desc
= &chip
->gpiodev
->descs
[offset
];
2312 if (test_bit(FLAG_REQUESTED
, &desc
->flags
) == 0)
2316 EXPORT_SYMBOL_GPL(gpiochip_is_requested
);
2319 * gpiochip_request_own_desc - Allow GPIO chip to request its own descriptor
2321 * @hwnum: hardware number of the GPIO for which to request the descriptor
2322 * @label: label for the GPIO
2324 * Function allows GPIO chip drivers to request and use their own GPIO
2325 * descriptors via gpiolib API. Difference to gpiod_request() is that this
2326 * function will not increase reference count of the GPIO chip module. This
2327 * allows the GPIO chip module to be unloaded as needed (we assume that the
2328 * GPIO chip driver handles freeing the GPIOs it has requested).
2331 * A pointer to the GPIO descriptor, or an ERR_PTR()-encoded negative error
2334 struct gpio_desc
*gpiochip_request_own_desc(struct gpio_chip
*chip
, u16 hwnum
,
2337 struct gpio_desc
*desc
= gpiochip_get_desc(chip
, hwnum
);
2341 chip_err(chip
, "failed to get GPIO descriptor\n");
2345 err
= gpiod_request_commit(desc
, label
);
2347 return ERR_PTR(err
);
2351 EXPORT_SYMBOL_GPL(gpiochip_request_own_desc
);
2354 * gpiochip_free_own_desc - Free GPIO requested by the chip driver
2355 * @desc: GPIO descriptor to free
2357 * Function frees the given GPIO requested previously with
2358 * gpiochip_request_own_desc().
2360 void gpiochip_free_own_desc(struct gpio_desc
*desc
)
2363 gpiod_free_commit(desc
);
2365 EXPORT_SYMBOL_GPL(gpiochip_free_own_desc
);
2368 * Drivers MUST set GPIO direction before making get/set calls. In
2369 * some cases this is done in early boot, before IRQs are enabled.
2371 * As a rule these aren't called more than once (except for drivers
2372 * using the open-drain emulation idiom) so these are natural places
2373 * to accumulate extra debugging checks. Note that we can't (yet)
2374 * rely on gpio_request() having been called beforehand.
2378 * gpiod_direction_input - set the GPIO direction to input
2379 * @desc: GPIO to set to input
2381 * Set the direction of the passed GPIO to input, such as gpiod_get_value() can
2382 * be called safely on it.
2384 * Return 0 in case of success, else an error code.
2386 int gpiod_direction_input(struct gpio_desc
*desc
)
2388 struct gpio_chip
*chip
;
2389 int status
= -EINVAL
;
2391 VALIDATE_DESC(desc
);
2392 chip
= desc
->gdev
->chip
;
2394 if (!chip
->get
|| !chip
->direction_input
) {
2396 "%s: missing get() or direction_input() operations\n",
2401 status
= chip
->direction_input(chip
, gpio_chip_hwgpio(desc
));
2403 clear_bit(FLAG_IS_OUT
, &desc
->flags
);
2405 trace_gpio_direction(desc_to_gpio(desc
), 1, status
);
2409 EXPORT_SYMBOL_GPL(gpiod_direction_input
);
2411 static int gpio_set_drive_single_ended(struct gpio_chip
*gc
, unsigned offset
,
2412 enum pin_config_param mode
)
2414 unsigned long config
= { PIN_CONF_PACKED(mode
, 0) };
2416 return gc
->set_config
? gc
->set_config(gc
, offset
, config
) : -ENOTSUPP
;
2419 static int gpiod_direction_output_raw_commit(struct gpio_desc
*desc
, int value
)
2421 struct gpio_chip
*gc
= desc
->gdev
->chip
;
2425 if (!gc
->set
|| !gc
->direction_output
) {
2427 "%s: missing set() or direction_output() operations\n",
2432 ret
= gc
->direction_output(gc
, gpio_chip_hwgpio(desc
), val
);
2434 set_bit(FLAG_IS_OUT
, &desc
->flags
);
2435 trace_gpio_value(desc_to_gpio(desc
), 0, val
);
2436 trace_gpio_direction(desc_to_gpio(desc
), 0, ret
);
2441 * gpiod_direction_output_raw - set the GPIO direction to output
2442 * @desc: GPIO to set to output
2443 * @value: initial output value of the GPIO
2445 * Set the direction of the passed GPIO to output, such as gpiod_set_value() can
2446 * be called safely on it. The initial value of the output must be specified
2447 * as raw value on the physical line without regard for the ACTIVE_LOW status.
2449 * Return 0 in case of success, else an error code.
2451 int gpiod_direction_output_raw(struct gpio_desc
*desc
, int value
)
2453 VALIDATE_DESC(desc
);
2454 return gpiod_direction_output_raw_commit(desc
, value
);
2456 EXPORT_SYMBOL_GPL(gpiod_direction_output_raw
);
2459 * gpiod_direction_output - set the GPIO direction to output
2460 * @desc: GPIO to set to output
2461 * @value: initial output value of the GPIO
2463 * Set the direction of the passed GPIO to output, such as gpiod_set_value() can
2464 * be called safely on it. The initial value of the output must be specified
2465 * as the logical value of the GPIO, i.e. taking its ACTIVE_LOW status into
2468 * Return 0 in case of success, else an error code.
2470 int gpiod_direction_output(struct gpio_desc
*desc
, int value
)
2472 struct gpio_chip
*gc
;
2475 VALIDATE_DESC(desc
);
2476 if (test_bit(FLAG_ACTIVE_LOW
, &desc
->flags
))
2481 /* GPIOs used for IRQs shall not be set as output */
2482 if (test_bit(FLAG_USED_AS_IRQ
, &desc
->flags
)) {
2484 "%s: tried to set a GPIO tied to an IRQ as output\n",
2489 gc
= desc
->gdev
->chip
;
2490 if (test_bit(FLAG_OPEN_DRAIN
, &desc
->flags
)) {
2491 /* First see if we can enable open drain in hardware */
2492 ret
= gpio_set_drive_single_ended(gc
, gpio_chip_hwgpio(desc
),
2493 PIN_CONFIG_DRIVE_OPEN_DRAIN
);
2495 goto set_output_value
;
2496 /* Emulate open drain by not actively driving the line high */
2498 return gpiod_direction_input(desc
);
2500 else if (test_bit(FLAG_OPEN_SOURCE
, &desc
->flags
)) {
2501 ret
= gpio_set_drive_single_ended(gc
, gpio_chip_hwgpio(desc
),
2502 PIN_CONFIG_DRIVE_OPEN_SOURCE
);
2504 goto set_output_value
;
2505 /* Emulate open source by not actively driving the line low */
2507 return gpiod_direction_input(desc
);
2509 gpio_set_drive_single_ended(gc
, gpio_chip_hwgpio(desc
),
2510 PIN_CONFIG_DRIVE_PUSH_PULL
);
2514 return gpiod_direction_output_raw_commit(desc
, value
);
2516 EXPORT_SYMBOL_GPL(gpiod_direction_output
);
2519 * gpiod_set_debounce - sets @debounce time for a GPIO
2520 * @desc: descriptor of the GPIO for which to set debounce time
2521 * @debounce: debounce time in microseconds
2524 * 0 on success, %-ENOTSUPP if the controller doesn't support setting the
2527 int gpiod_set_debounce(struct gpio_desc
*desc
, unsigned debounce
)
2529 struct gpio_chip
*chip
;
2530 unsigned long config
;
2532 VALIDATE_DESC(desc
);
2533 chip
= desc
->gdev
->chip
;
2534 if (!chip
->set
|| !chip
->set_config
) {
2536 "%s: missing set() or set_config() operations\n",
2541 config
= pinconf_to_config_packed(PIN_CONFIG_INPUT_DEBOUNCE
, debounce
);
2542 return chip
->set_config(chip
, gpio_chip_hwgpio(desc
), config
);
2544 EXPORT_SYMBOL_GPL(gpiod_set_debounce
);
2547 * gpiod_is_active_low - test whether a GPIO is active-low or not
2548 * @desc: the gpio descriptor to test
2550 * Returns 1 if the GPIO is active-low, 0 otherwise.
2552 int gpiod_is_active_low(const struct gpio_desc
*desc
)
2554 VALIDATE_DESC(desc
);
2555 return test_bit(FLAG_ACTIVE_LOW
, &desc
->flags
);
2557 EXPORT_SYMBOL_GPL(gpiod_is_active_low
);
2559 /* I/O calls are only valid after configuration completed; the relevant
2560 * "is this a valid GPIO" error checks should already have been done.
2562 * "Get" operations are often inlinable as reading a pin value register,
2563 * and masking the relevant bit in that register.
2565 * When "set" operations are inlinable, they involve writing that mask to
2566 * one register to set a low value, or a different register to set it high.
2567 * Otherwise locking is needed, so there may be little value to inlining.
2569 *------------------------------------------------------------------------
2571 * IMPORTANT!!! The hot paths -- get/set value -- assume that callers
2572 * have requested the GPIO. That can include implicit requesting by
2573 * a direction setting call. Marking a gpio as requested locks its chip
2574 * in memory, guaranteeing that these table lookups need no more locking
2575 * and that gpiochip_remove() will fail.
2577 * REVISIT when debugging, consider adding some instrumentation to ensure
2578 * that the GPIO was actually requested.
2581 static int gpiod_get_raw_value_commit(const struct gpio_desc
*desc
)
2583 struct gpio_chip
*chip
;
2587 chip
= desc
->gdev
->chip
;
2588 offset
= gpio_chip_hwgpio(desc
);
2589 value
= chip
->get
? chip
->get(chip
, offset
) : -EIO
;
2590 value
= value
< 0 ? value
: !!value
;
2591 trace_gpio_value(desc_to_gpio(desc
), 1, value
);
2595 static int gpio_chip_get_multiple(struct gpio_chip
*chip
,
2596 unsigned long *mask
, unsigned long *bits
)
2598 if (chip
->get_multiple
) {
2599 return chip
->get_multiple(chip
, mask
, bits
);
2600 } else if (chip
->get
) {
2603 for_each_set_bit(i
, mask
, chip
->ngpio
) {
2604 value
= chip
->get(chip
, i
);
2607 __assign_bit(i
, bits
, value
);
2614 int gpiod_get_array_value_complex(bool raw
, bool can_sleep
,
2615 unsigned int array_size
,
2616 struct gpio_desc
**desc_array
,
2621 while (i
< array_size
) {
2622 struct gpio_chip
*chip
= desc_array
[i
]->gdev
->chip
;
2623 unsigned long mask
[BITS_TO_LONGS(chip
->ngpio
)];
2624 unsigned long bits
[BITS_TO_LONGS(chip
->ngpio
)];
2628 WARN_ON(chip
->can_sleep
);
2630 /* collect all inputs belonging to the same chip */
2632 memset(mask
, 0, sizeof(mask
));
2634 const struct gpio_desc
*desc
= desc_array
[i
];
2635 int hwgpio
= gpio_chip_hwgpio(desc
);
2637 __set_bit(hwgpio
, mask
);
2639 } while ((i
< array_size
) &&
2640 (desc_array
[i
]->gdev
->chip
== chip
));
2642 ret
= gpio_chip_get_multiple(chip
, mask
, bits
);
2646 for (j
= first
; j
< i
; j
++) {
2647 const struct gpio_desc
*desc
= desc_array
[j
];
2648 int hwgpio
= gpio_chip_hwgpio(desc
);
2649 int value
= test_bit(hwgpio
, bits
);
2651 if (!raw
&& test_bit(FLAG_ACTIVE_LOW
, &desc
->flags
))
2653 value_array
[j
] = value
;
2654 trace_gpio_value(desc_to_gpio(desc
), 1, value
);
2661 * gpiod_get_raw_value() - return a gpio's raw value
2662 * @desc: gpio whose value will be returned
2664 * Return the GPIO's raw value, i.e. the value of the physical line disregarding
2665 * its ACTIVE_LOW status, or negative errno on failure.
2667 * This function should be called from contexts where we cannot sleep, and will
2668 * complain if the GPIO chip functions potentially sleep.
2670 int gpiod_get_raw_value(const struct gpio_desc
*desc
)
2672 VALIDATE_DESC(desc
);
2673 /* Should be using gpio_get_value_cansleep() */
2674 WARN_ON(desc
->gdev
->chip
->can_sleep
);
2675 return gpiod_get_raw_value_commit(desc
);
2677 EXPORT_SYMBOL_GPL(gpiod_get_raw_value
);
2680 * gpiod_get_value() - return a gpio's value
2681 * @desc: gpio whose value will be returned
2683 * Return the GPIO's logical value, i.e. taking the ACTIVE_LOW status into
2684 * account, or negative errno on failure.
2686 * This function should be called from contexts where we cannot sleep, and will
2687 * complain if the GPIO chip functions potentially sleep.
2689 int gpiod_get_value(const struct gpio_desc
*desc
)
2693 VALIDATE_DESC(desc
);
2694 /* Should be using gpio_get_value_cansleep() */
2695 WARN_ON(desc
->gdev
->chip
->can_sleep
);
2697 value
= gpiod_get_raw_value_commit(desc
);
2701 if (test_bit(FLAG_ACTIVE_LOW
, &desc
->flags
))
2706 EXPORT_SYMBOL_GPL(gpiod_get_value
);
2709 * gpiod_get_raw_array_value() - read raw values from an array of GPIOs
2710 * @array_size: number of elements in the descriptor / value arrays
2711 * @desc_array: array of GPIO descriptors whose values will be read
2712 * @value_array: array to store the read values
2714 * Read the raw values of the GPIOs, i.e. the values of the physical lines
2715 * without regard for their ACTIVE_LOW status. Return 0 in case of success,
2716 * else an error code.
2718 * This function should be called from contexts where we cannot sleep,
2719 * and it will complain if the GPIO chip functions potentially sleep.
2721 int gpiod_get_raw_array_value(unsigned int array_size
,
2722 struct gpio_desc
**desc_array
, int *value_array
)
2726 return gpiod_get_array_value_complex(true, false, array_size
,
2727 desc_array
, value_array
);
2729 EXPORT_SYMBOL_GPL(gpiod_get_raw_array_value
);
2732 * gpiod_get_array_value() - read values from an array of GPIOs
2733 * @array_size: number of elements in the descriptor / value arrays
2734 * @desc_array: array of GPIO descriptors whose values will be read
2735 * @value_array: array to store the read values
2737 * Read the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status
2738 * into account. Return 0 in case of success, else an error code.
2740 * This function should be called from contexts where we cannot sleep,
2741 * and it will complain if the GPIO chip functions potentially sleep.
2743 int gpiod_get_array_value(unsigned int array_size
,
2744 struct gpio_desc
**desc_array
, int *value_array
)
2748 return gpiod_get_array_value_complex(false, false, array_size
,
2749 desc_array
, value_array
);
2751 EXPORT_SYMBOL_GPL(gpiod_get_array_value
);
2754 * gpio_set_open_drain_value_commit() - Set the open drain gpio's value.
2755 * @desc: gpio descriptor whose state need to be set.
2756 * @value: Non-zero for setting it HIGH otherwise it will set to LOW.
2758 static void gpio_set_open_drain_value_commit(struct gpio_desc
*desc
, bool value
)
2761 struct gpio_chip
*chip
= desc
->gdev
->chip
;
2762 int offset
= gpio_chip_hwgpio(desc
);
2765 err
= chip
->direction_input(chip
, offset
);
2767 clear_bit(FLAG_IS_OUT
, &desc
->flags
);
2769 err
= chip
->direction_output(chip
, offset
, 0);
2771 set_bit(FLAG_IS_OUT
, &desc
->flags
);
2773 trace_gpio_direction(desc_to_gpio(desc
), value
, err
);
2776 "%s: Error in set_value for open drain err %d\n",
2781 * _gpio_set_open_source_value() - Set the open source gpio's value.
2782 * @desc: gpio descriptor whose state need to be set.
2783 * @value: Non-zero for setting it HIGH otherwise it will set to LOW.
2785 static void gpio_set_open_source_value_commit(struct gpio_desc
*desc
, bool value
)
2788 struct gpio_chip
*chip
= desc
->gdev
->chip
;
2789 int offset
= gpio_chip_hwgpio(desc
);
2792 err
= chip
->direction_output(chip
, offset
, 1);
2794 set_bit(FLAG_IS_OUT
, &desc
->flags
);
2796 err
= chip
->direction_input(chip
, offset
);
2798 clear_bit(FLAG_IS_OUT
, &desc
->flags
);
2800 trace_gpio_direction(desc_to_gpio(desc
), !value
, err
);
2803 "%s: Error in set_value for open source err %d\n",
2807 static void gpiod_set_raw_value_commit(struct gpio_desc
*desc
, bool value
)
2809 struct gpio_chip
*chip
;
2811 chip
= desc
->gdev
->chip
;
2812 trace_gpio_value(desc_to_gpio(desc
), 0, value
);
2813 chip
->set(chip
, gpio_chip_hwgpio(desc
), value
);
2817 * set multiple outputs on the same chip;
2818 * use the chip's set_multiple function if available;
2819 * otherwise set the outputs sequentially;
2820 * @mask: bit mask array; one bit per output; BITS_PER_LONG bits per word
2821 * defines which outputs are to be changed
2822 * @bits: bit value array; one bit per output; BITS_PER_LONG bits per word
2823 * defines the values the outputs specified by mask are to be set to
2825 static void gpio_chip_set_multiple(struct gpio_chip
*chip
,
2826 unsigned long *mask
, unsigned long *bits
)
2828 if (chip
->set_multiple
) {
2829 chip
->set_multiple(chip
, mask
, bits
);
2833 /* set outputs if the corresponding mask bit is set */
2834 for_each_set_bit(i
, mask
, chip
->ngpio
)
2835 chip
->set(chip
, i
, test_bit(i
, bits
));
2839 void gpiod_set_array_value_complex(bool raw
, bool can_sleep
,
2840 unsigned int array_size
,
2841 struct gpio_desc
**desc_array
,
2846 while (i
< array_size
) {
2847 struct gpio_chip
*chip
= desc_array
[i
]->gdev
->chip
;
2848 unsigned long mask
[BITS_TO_LONGS(chip
->ngpio
)];
2849 unsigned long bits
[BITS_TO_LONGS(chip
->ngpio
)];
2853 WARN_ON(chip
->can_sleep
);
2855 memset(mask
, 0, sizeof(mask
));
2857 struct gpio_desc
*desc
= desc_array
[i
];
2858 int hwgpio
= gpio_chip_hwgpio(desc
);
2859 int value
= value_array
[i
];
2861 if (!raw
&& test_bit(FLAG_ACTIVE_LOW
, &desc
->flags
))
2863 trace_gpio_value(desc_to_gpio(desc
), 0, value
);
2865 * collect all normal outputs belonging to the same chip
2866 * open drain and open source outputs are set individually
2868 if (test_bit(FLAG_OPEN_DRAIN
, &desc
->flags
) && !raw
) {
2869 gpio_set_open_drain_value_commit(desc
, value
);
2870 } else if (test_bit(FLAG_OPEN_SOURCE
, &desc
->flags
) && !raw
) {
2871 gpio_set_open_source_value_commit(desc
, value
);
2873 __set_bit(hwgpio
, mask
);
2875 __set_bit(hwgpio
, bits
);
2877 __clear_bit(hwgpio
, bits
);
2881 } while ((i
< array_size
) &&
2882 (desc_array
[i
]->gdev
->chip
== chip
));
2883 /* push collected bits to outputs */
2885 gpio_chip_set_multiple(chip
, mask
, bits
);
2890 * gpiod_set_raw_value() - assign a gpio's raw value
2891 * @desc: gpio whose value will be assigned
2892 * @value: value to assign
2894 * Set the raw value of the GPIO, i.e. the value of its physical line without
2895 * regard for its ACTIVE_LOW status.
2897 * This function should be called from contexts where we cannot sleep, and will
2898 * complain if the GPIO chip functions potentially sleep.
2900 void gpiod_set_raw_value(struct gpio_desc
*desc
, int value
)
2902 VALIDATE_DESC_VOID(desc
);
2903 /* Should be using gpiod_set_value_cansleep() */
2904 WARN_ON(desc
->gdev
->chip
->can_sleep
);
2905 gpiod_set_raw_value_commit(desc
, value
);
2907 EXPORT_SYMBOL_GPL(gpiod_set_raw_value
);
2910 * gpiod_set_value_nocheck() - set a GPIO line value without checking
2911 * @desc: the descriptor to set the value on
2912 * @value: value to set
2914 * This sets the value of a GPIO line backing a descriptor, applying
2915 * different semantic quirks like active low and open drain/source
2918 static void gpiod_set_value_nocheck(struct gpio_desc
*desc
, int value
)
2920 if (test_bit(FLAG_ACTIVE_LOW
, &desc
->flags
))
2922 if (test_bit(FLAG_OPEN_DRAIN
, &desc
->flags
))
2923 gpio_set_open_drain_value_commit(desc
, value
);
2924 else if (test_bit(FLAG_OPEN_SOURCE
, &desc
->flags
))
2925 gpio_set_open_source_value_commit(desc
, value
);
2927 gpiod_set_raw_value_commit(desc
, value
);
2931 * gpiod_set_value() - assign a gpio's value
2932 * @desc: gpio whose value will be assigned
2933 * @value: value to assign
2935 * Set the logical value of the GPIO, i.e. taking its ACTIVE_LOW,
2936 * OPEN_DRAIN and OPEN_SOURCE flags into account.
2938 * This function should be called from contexts where we cannot sleep, and will
2939 * complain if the GPIO chip functions potentially sleep.
2941 void gpiod_set_value(struct gpio_desc
*desc
, int value
)
2943 VALIDATE_DESC_VOID(desc
);
2944 WARN_ON(desc
->gdev
->chip
->can_sleep
);
2945 gpiod_set_value_nocheck(desc
, value
);
2947 EXPORT_SYMBOL_GPL(gpiod_set_value
);
2950 * gpiod_set_raw_array_value() - assign values to an array of GPIOs
2951 * @array_size: number of elements in the descriptor / value arrays
2952 * @desc_array: array of GPIO descriptors whose values will be assigned
2953 * @value_array: array of values to assign
2955 * Set the raw values of the GPIOs, i.e. the values of the physical lines
2956 * without regard for their ACTIVE_LOW status.
2958 * This function should be called from contexts where we cannot sleep, and will
2959 * complain if the GPIO chip functions potentially sleep.
2961 void gpiod_set_raw_array_value(unsigned int array_size
,
2962 struct gpio_desc
**desc_array
, int *value_array
)
2966 gpiod_set_array_value_complex(true, false, array_size
, desc_array
,
2969 EXPORT_SYMBOL_GPL(gpiod_set_raw_array_value
);
2972 * gpiod_set_array_value() - assign values to an array of GPIOs
2973 * @array_size: number of elements in the descriptor / value arrays
2974 * @desc_array: array of GPIO descriptors whose values will be assigned
2975 * @value_array: array of values to assign
2977 * Set the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status
2980 * This function should be called from contexts where we cannot sleep, and will
2981 * complain if the GPIO chip functions potentially sleep.
2983 void gpiod_set_array_value(unsigned int array_size
,
2984 struct gpio_desc
**desc_array
, int *value_array
)
2988 gpiod_set_array_value_complex(false, false, array_size
, desc_array
,
2991 EXPORT_SYMBOL_GPL(gpiod_set_array_value
);
2994 * gpiod_cansleep() - report whether gpio value access may sleep
2995 * @desc: gpio to check
2998 int gpiod_cansleep(const struct gpio_desc
*desc
)
3000 VALIDATE_DESC(desc
);
3001 return desc
->gdev
->chip
->can_sleep
;
3003 EXPORT_SYMBOL_GPL(gpiod_cansleep
);
3006 * gpiod_to_irq() - return the IRQ corresponding to a GPIO
3007 * @desc: gpio whose IRQ will be returned (already requested)
3009 * Return the IRQ corresponding to the passed GPIO, or an error code in case of
3012 int gpiod_to_irq(const struct gpio_desc
*desc
)
3014 struct gpio_chip
*chip
;
3018 * Cannot VALIDATE_DESC() here as gpiod_to_irq() consumer semantics
3019 * requires this function to not return zero on an invalid descriptor
3020 * but rather a negative error number.
3022 if (!desc
|| IS_ERR(desc
) || !desc
->gdev
|| !desc
->gdev
->chip
)
3025 chip
= desc
->gdev
->chip
;
3026 offset
= gpio_chip_hwgpio(desc
);
3028 int retirq
= chip
->to_irq(chip
, offset
);
3030 /* Zero means NO_IRQ */
3038 EXPORT_SYMBOL_GPL(gpiod_to_irq
);
3041 * gpiochip_lock_as_irq() - lock a GPIO to be used as IRQ
3042 * @chip: the chip the GPIO to lock belongs to
3043 * @offset: the offset of the GPIO to lock as IRQ
3045 * This is used directly by GPIO drivers that want to lock down
3046 * a certain GPIO line to be used for IRQs.
3048 int gpiochip_lock_as_irq(struct gpio_chip
*chip
, unsigned int offset
)
3050 struct gpio_desc
*desc
;
3052 desc
= gpiochip_get_desc(chip
, offset
);
3054 return PTR_ERR(desc
);
3057 * If it's fast: flush the direction setting if something changed
3060 if (!chip
->can_sleep
&& chip
->get_direction
) {
3061 int dir
= chip
->get_direction(chip
, offset
);
3064 clear_bit(FLAG_IS_OUT
, &desc
->flags
);
3066 set_bit(FLAG_IS_OUT
, &desc
->flags
);
3069 if (test_bit(FLAG_IS_OUT
, &desc
->flags
)) {
3071 "%s: tried to flag a GPIO set as output for IRQ\n",
3076 set_bit(FLAG_USED_AS_IRQ
, &desc
->flags
);
3079 * If the consumer has not set up a label (such as when the
3080 * IRQ is referenced from .to_irq()) we set up a label here
3081 * so it is clear this is used as an interrupt.
3084 desc_set_label(desc
, "interrupt");
3088 EXPORT_SYMBOL_GPL(gpiochip_lock_as_irq
);
3091 * gpiochip_unlock_as_irq() - unlock a GPIO used as IRQ
3092 * @chip: the chip the GPIO to lock belongs to
3093 * @offset: the offset of the GPIO to lock as IRQ
3095 * This is used directly by GPIO drivers that want to indicate
3096 * that a certain GPIO is no longer used exclusively for IRQ.
3098 void gpiochip_unlock_as_irq(struct gpio_chip
*chip
, unsigned int offset
)
3100 struct gpio_desc
*desc
;
3102 desc
= gpiochip_get_desc(chip
, offset
);
3106 clear_bit(FLAG_USED_AS_IRQ
, &desc
->flags
);
3108 /* If we only had this marking, erase it */
3109 if (desc
->label
&& !strcmp(desc
->label
, "interrupt"))
3110 desc_set_label(desc
, NULL
);
3112 EXPORT_SYMBOL_GPL(gpiochip_unlock_as_irq
);
3114 bool gpiochip_line_is_irq(struct gpio_chip
*chip
, unsigned int offset
)
3116 if (offset
>= chip
->ngpio
)
3119 return test_bit(FLAG_USED_AS_IRQ
, &chip
->gpiodev
->descs
[offset
].flags
);
3121 EXPORT_SYMBOL_GPL(gpiochip_line_is_irq
);
3123 bool gpiochip_line_is_open_drain(struct gpio_chip
*chip
, unsigned int offset
)
3125 if (offset
>= chip
->ngpio
)
3128 return test_bit(FLAG_OPEN_DRAIN
, &chip
->gpiodev
->descs
[offset
].flags
);
3130 EXPORT_SYMBOL_GPL(gpiochip_line_is_open_drain
);
3132 bool gpiochip_line_is_open_source(struct gpio_chip
*chip
, unsigned int offset
)
3134 if (offset
>= chip
->ngpio
)
3137 return test_bit(FLAG_OPEN_SOURCE
, &chip
->gpiodev
->descs
[offset
].flags
);
3139 EXPORT_SYMBOL_GPL(gpiochip_line_is_open_source
);
3141 bool gpiochip_line_is_persistent(struct gpio_chip
*chip
, unsigned int offset
)
3143 if (offset
>= chip
->ngpio
)
3146 return !test_bit(FLAG_SLEEP_MAY_LOSE_VALUE
,
3147 &chip
->gpiodev
->descs
[offset
].flags
);
3149 EXPORT_SYMBOL_GPL(gpiochip_line_is_persistent
);
3152 * gpiod_get_raw_value_cansleep() - return a gpio's raw value
3153 * @desc: gpio whose value will be returned
3155 * Return the GPIO's raw value, i.e. the value of the physical line disregarding
3156 * its ACTIVE_LOW status, or negative errno on failure.
3158 * This function is to be called from contexts that can sleep.
3160 int gpiod_get_raw_value_cansleep(const struct gpio_desc
*desc
)
3162 might_sleep_if(extra_checks
);
3163 VALIDATE_DESC(desc
);
3164 return gpiod_get_raw_value_commit(desc
);
3166 EXPORT_SYMBOL_GPL(gpiod_get_raw_value_cansleep
);
3169 * gpiod_get_value_cansleep() - return a gpio's value
3170 * @desc: gpio whose value will be returned
3172 * Return the GPIO's logical value, i.e. taking the ACTIVE_LOW status into
3173 * account, or negative errno on failure.
3175 * This function is to be called from contexts that can sleep.
3177 int gpiod_get_value_cansleep(const struct gpio_desc
*desc
)
3181 might_sleep_if(extra_checks
);
3182 VALIDATE_DESC(desc
);
3183 value
= gpiod_get_raw_value_commit(desc
);
3187 if (test_bit(FLAG_ACTIVE_LOW
, &desc
->flags
))
3192 EXPORT_SYMBOL_GPL(gpiod_get_value_cansleep
);
3195 * gpiod_get_raw_array_value_cansleep() - read raw values from an array of GPIOs
3196 * @array_size: number of elements in the descriptor / value arrays
3197 * @desc_array: array of GPIO descriptors whose values will be read
3198 * @value_array: array to store the read values
3200 * Read the raw values of the GPIOs, i.e. the values of the physical lines
3201 * without regard for their ACTIVE_LOW status. Return 0 in case of success,
3202 * else an error code.
3204 * This function is to be called from contexts that can sleep.
3206 int gpiod_get_raw_array_value_cansleep(unsigned int array_size
,
3207 struct gpio_desc
**desc_array
,
3210 might_sleep_if(extra_checks
);
3213 return gpiod_get_array_value_complex(true, true, array_size
,
3214 desc_array
, value_array
);
3216 EXPORT_SYMBOL_GPL(gpiod_get_raw_array_value_cansleep
);
3219 * gpiod_get_array_value_cansleep() - read values from an array of GPIOs
3220 * @array_size: number of elements in the descriptor / value arrays
3221 * @desc_array: array of GPIO descriptors whose values will be read
3222 * @value_array: array to store the read values
3224 * Read the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status
3225 * into account. Return 0 in case of success, else an error code.
3227 * This function is to be called from contexts that can sleep.
3229 int gpiod_get_array_value_cansleep(unsigned int array_size
,
3230 struct gpio_desc
**desc_array
,
3233 might_sleep_if(extra_checks
);
3236 return gpiod_get_array_value_complex(false, true, array_size
,
3237 desc_array
, value_array
);
3239 EXPORT_SYMBOL_GPL(gpiod_get_array_value_cansleep
);
3242 * gpiod_set_raw_value_cansleep() - assign a gpio's raw value
3243 * @desc: gpio whose value will be assigned
3244 * @value: value to assign
3246 * Set the raw value of the GPIO, i.e. the value of its physical line without
3247 * regard for its ACTIVE_LOW status.
3249 * This function is to be called from contexts that can sleep.
3251 void gpiod_set_raw_value_cansleep(struct gpio_desc
*desc
, int value
)
3253 might_sleep_if(extra_checks
);
3254 VALIDATE_DESC_VOID(desc
);
3255 gpiod_set_raw_value_commit(desc
, value
);
3257 EXPORT_SYMBOL_GPL(gpiod_set_raw_value_cansleep
);
3260 * gpiod_set_value_cansleep() - assign a gpio's value
3261 * @desc: gpio whose value will be assigned
3262 * @value: value to assign
3264 * Set the logical value of the GPIO, i.e. taking its ACTIVE_LOW status into
3267 * This function is to be called from contexts that can sleep.
3269 void gpiod_set_value_cansleep(struct gpio_desc
*desc
, int value
)
3271 might_sleep_if(extra_checks
);
3272 VALIDATE_DESC_VOID(desc
);
3273 gpiod_set_value_nocheck(desc
, value
);
3275 EXPORT_SYMBOL_GPL(gpiod_set_value_cansleep
);
3278 * gpiod_set_raw_array_value_cansleep() - assign values to an array of GPIOs
3279 * @array_size: number of elements in the descriptor / value arrays
3280 * @desc_array: array of GPIO descriptors whose values will be assigned
3281 * @value_array: array of values to assign
3283 * Set the raw values of the GPIOs, i.e. the values of the physical lines
3284 * without regard for their ACTIVE_LOW status.
3286 * This function is to be called from contexts that can sleep.
3288 void gpiod_set_raw_array_value_cansleep(unsigned int array_size
,
3289 struct gpio_desc
**desc_array
,
3292 might_sleep_if(extra_checks
);
3295 gpiod_set_array_value_complex(true, true, array_size
, desc_array
,
3298 EXPORT_SYMBOL_GPL(gpiod_set_raw_array_value_cansleep
);
3301 * gpiod_add_lookup_tables() - register GPIO device consumers
3302 * @tables: list of tables of consumers to register
3303 * @n: number of tables in the list
3305 void gpiod_add_lookup_tables(struct gpiod_lookup_table
**tables
, size_t n
)
3309 mutex_lock(&gpio_lookup_lock
);
3311 for (i
= 0; i
< n
; i
++)
3312 list_add_tail(&tables
[i
]->list
, &gpio_lookup_list
);
3314 mutex_unlock(&gpio_lookup_lock
);
3318 * gpiod_set_array_value_cansleep() - assign values to an array of GPIOs
3319 * @array_size: number of elements in the descriptor / value arrays
3320 * @desc_array: array of GPIO descriptors whose values will be assigned
3321 * @value_array: array of values to assign
3323 * Set the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status
3326 * This function is to be called from contexts that can sleep.
3328 void gpiod_set_array_value_cansleep(unsigned int array_size
,
3329 struct gpio_desc
**desc_array
,
3332 might_sleep_if(extra_checks
);
3335 gpiod_set_array_value_complex(false, true, array_size
, desc_array
,
3338 EXPORT_SYMBOL_GPL(gpiod_set_array_value_cansleep
);
3341 * gpiod_add_lookup_table() - register GPIO device consumers
3342 * @table: table of consumers to register
3344 void gpiod_add_lookup_table(struct gpiod_lookup_table
*table
)
3346 mutex_lock(&gpio_lookup_lock
);
3348 list_add_tail(&table
->list
, &gpio_lookup_list
);
3350 mutex_unlock(&gpio_lookup_lock
);
3352 EXPORT_SYMBOL_GPL(gpiod_add_lookup_table
);
3355 * gpiod_remove_lookup_table() - unregister GPIO device consumers
3356 * @table: table of consumers to unregister
3358 void gpiod_remove_lookup_table(struct gpiod_lookup_table
*table
)
3360 mutex_lock(&gpio_lookup_lock
);
3362 list_del(&table
->list
);
3364 mutex_unlock(&gpio_lookup_lock
);
3366 EXPORT_SYMBOL_GPL(gpiod_remove_lookup_table
);
3368 static struct gpiod_lookup_table
*gpiod_find_lookup_table(struct device
*dev
)
3370 const char *dev_id
= dev
? dev_name(dev
) : NULL
;
3371 struct gpiod_lookup_table
*table
;
3373 mutex_lock(&gpio_lookup_lock
);
3375 list_for_each_entry(table
, &gpio_lookup_list
, list
) {
3376 if (table
->dev_id
&& dev_id
) {
3378 * Valid strings on both ends, must be identical to have
3381 if (!strcmp(table
->dev_id
, dev_id
))
3385 * One of the pointers is NULL, so both must be to have
3388 if (dev_id
== table
->dev_id
)
3395 mutex_unlock(&gpio_lookup_lock
);
3399 static struct gpio_desc
*gpiod_find(struct device
*dev
, const char *con_id
,
3401 enum gpio_lookup_flags
*flags
)
3403 struct gpio_desc
*desc
= ERR_PTR(-ENOENT
);
3404 struct gpiod_lookup_table
*table
;
3405 struct gpiod_lookup
*p
;
3407 table
= gpiod_find_lookup_table(dev
);
3411 for (p
= &table
->table
[0]; p
->chip_label
; p
++) {
3412 struct gpio_chip
*chip
;
3414 /* idx must always match exactly */
3418 /* If the lookup entry has a con_id, require exact match */
3419 if (p
->con_id
&& (!con_id
|| strcmp(p
->con_id
, con_id
)))
3422 chip
= find_chip_by_name(p
->chip_label
);
3425 dev_err(dev
, "cannot find GPIO chip %s\n",
3427 return ERR_PTR(-ENODEV
);
3430 if (chip
->ngpio
<= p
->chip_hwnum
) {
3432 "requested GPIO %d is out of range [0..%d] for chip %s\n",
3433 idx
, chip
->ngpio
, chip
->label
);
3434 return ERR_PTR(-EINVAL
);
3437 desc
= gpiochip_get_desc(chip
, p
->chip_hwnum
);
3446 static int dt_gpio_count(struct device
*dev
, const char *con_id
)
3452 for (i
= 0; i
< ARRAY_SIZE(gpio_suffixes
); i
++) {
3454 snprintf(propname
, sizeof(propname
), "%s-%s",
3455 con_id
, gpio_suffixes
[i
]);
3457 snprintf(propname
, sizeof(propname
), "%s",
3460 ret
= of_gpio_named_count(dev
->of_node
, propname
);
3464 return ret
? ret
: -ENOENT
;
3467 static int platform_gpio_count(struct device
*dev
, const char *con_id
)
3469 struct gpiod_lookup_table
*table
;
3470 struct gpiod_lookup
*p
;
3471 unsigned int count
= 0;
3473 table
= gpiod_find_lookup_table(dev
);
3477 for (p
= &table
->table
[0]; p
->chip_label
; p
++) {
3478 if ((con_id
&& p
->con_id
&& !strcmp(con_id
, p
->con_id
)) ||
3479 (!con_id
&& !p
->con_id
))
3489 * gpiod_count - return the number of GPIOs associated with a device / function
3490 * or -ENOENT if no GPIO has been assigned to the requested function
3491 * @dev: GPIO consumer, can be NULL for system-global GPIOs
3492 * @con_id: function within the GPIO consumer
3494 int gpiod_count(struct device
*dev
, const char *con_id
)
3496 int count
= -ENOENT
;
3498 if (IS_ENABLED(CONFIG_OF
) && dev
&& dev
->of_node
)
3499 count
= dt_gpio_count(dev
, con_id
);
3500 else if (IS_ENABLED(CONFIG_ACPI
) && dev
&& ACPI_HANDLE(dev
))
3501 count
= acpi_gpio_count(dev
, con_id
);
3504 count
= platform_gpio_count(dev
, con_id
);
3508 EXPORT_SYMBOL_GPL(gpiod_count
);
3511 * gpiod_get - obtain a GPIO for a given GPIO function
3512 * @dev: GPIO consumer, can be NULL for system-global GPIOs
3513 * @con_id: function within the GPIO consumer
3514 * @flags: optional GPIO initialization flags
3516 * Return the GPIO descriptor corresponding to the function con_id of device
3517 * dev, -ENOENT if no GPIO has been assigned to the requested function, or
3518 * another IS_ERR() code if an error occurred while trying to acquire the GPIO.
3520 struct gpio_desc
*__must_check
gpiod_get(struct device
*dev
, const char *con_id
,
3521 enum gpiod_flags flags
)
3523 return gpiod_get_index(dev
, con_id
, 0, flags
);
3525 EXPORT_SYMBOL_GPL(gpiod_get
);
3528 * gpiod_get_optional - obtain an optional GPIO for a given GPIO function
3529 * @dev: GPIO consumer, can be NULL for system-global GPIOs
3530 * @con_id: function within the GPIO consumer
3531 * @flags: optional GPIO initialization flags
3533 * This is equivalent to gpiod_get(), except that when no GPIO was assigned to
3534 * the requested function it will return NULL. This is convenient for drivers
3535 * that need to handle optional GPIOs.
3537 struct gpio_desc
*__must_check
gpiod_get_optional(struct device
*dev
,
3539 enum gpiod_flags flags
)
3541 return gpiod_get_index_optional(dev
, con_id
, 0, flags
);
3543 EXPORT_SYMBOL_GPL(gpiod_get_optional
);
3547 * gpiod_configure_flags - helper function to configure a given GPIO
3548 * @desc: gpio whose value will be assigned
3549 * @con_id: function within the GPIO consumer
3550 * @lflags: gpio_lookup_flags - returned from of_find_gpio() or
3552 * @dflags: gpiod_flags - optional GPIO initialization flags
3554 * Return 0 on success, -ENOENT if no GPIO has been assigned to the
3555 * requested function and/or index, or another IS_ERR() code if an error
3556 * occurred while trying to acquire the GPIO.
3558 int gpiod_configure_flags(struct gpio_desc
*desc
, const char *con_id
,
3559 unsigned long lflags
, enum gpiod_flags dflags
)
3563 if (lflags
& GPIO_ACTIVE_LOW
)
3564 set_bit(FLAG_ACTIVE_LOW
, &desc
->flags
);
3566 if (lflags
& GPIO_OPEN_DRAIN
)
3567 set_bit(FLAG_OPEN_DRAIN
, &desc
->flags
);
3568 else if (dflags
& GPIOD_FLAGS_BIT_OPEN_DRAIN
) {
3570 * This enforces open drain mode from the consumer side.
3571 * This is necessary for some busses like I2C, but the lookup
3572 * should *REALLY* have specified them as open drain in the
3573 * first place, so print a little warning here.
3575 set_bit(FLAG_OPEN_DRAIN
, &desc
->flags
);
3577 "enforced open drain please flag it properly in DT/ACPI DSDT/board file\n");
3580 if (lflags
& GPIO_OPEN_SOURCE
)
3581 set_bit(FLAG_OPEN_SOURCE
, &desc
->flags
);
3582 if (lflags
& GPIO_SLEEP_MAY_LOSE_VALUE
)
3583 set_bit(FLAG_SLEEP_MAY_LOSE_VALUE
, &desc
->flags
);
3585 /* No particular flag request, return here... */
3586 if (!(dflags
& GPIOD_FLAGS_BIT_DIR_SET
)) {
3587 pr_debug("no flags found for %s\n", con_id
);
3592 if (dflags
& GPIOD_FLAGS_BIT_DIR_OUT
)
3593 status
= gpiod_direction_output(desc
,
3594 !!(dflags
& GPIOD_FLAGS_BIT_DIR_VAL
));
3596 status
= gpiod_direction_input(desc
);
3602 * gpiod_get_index - obtain a GPIO from a multi-index GPIO function
3603 * @dev: GPIO consumer, can be NULL for system-global GPIOs
3604 * @con_id: function within the GPIO consumer
3605 * @idx: index of the GPIO to obtain in the consumer
3606 * @flags: optional GPIO initialization flags
3608 * This variant of gpiod_get() allows to access GPIOs other than the first
3609 * defined one for functions that define several GPIOs.
3611 * Return a valid GPIO descriptor, -ENOENT if no GPIO has been assigned to the
3612 * requested function and/or index, or another IS_ERR() code if an error
3613 * occurred while trying to acquire the GPIO.
3615 struct gpio_desc
*__must_check
gpiod_get_index(struct device
*dev
,
3618 enum gpiod_flags flags
)
3620 struct gpio_desc
*desc
= NULL
;
3622 enum gpio_lookup_flags lookupflags
= 0;
3623 /* Maybe we have a device name, maybe not */
3624 const char *devname
= dev
? dev_name(dev
) : "?";
3626 dev_dbg(dev
, "GPIO lookup for consumer %s\n", con_id
);
3629 /* Using device tree? */
3630 if (IS_ENABLED(CONFIG_OF
) && dev
->of_node
) {
3631 dev_dbg(dev
, "using device tree for GPIO lookup\n");
3632 desc
= of_find_gpio(dev
, con_id
, idx
, &lookupflags
);
3633 } else if (ACPI_COMPANION(dev
)) {
3634 dev_dbg(dev
, "using ACPI for GPIO lookup\n");
3635 desc
= acpi_find_gpio(dev
, con_id
, idx
, &flags
, &lookupflags
);
3640 * Either we are not using DT or ACPI, or their lookup did not return
3641 * a result. In that case, use platform lookup as a fallback.
3643 if (!desc
|| desc
== ERR_PTR(-ENOENT
)) {
3644 dev_dbg(dev
, "using lookup tables for GPIO lookup\n");
3645 desc
= gpiod_find(dev
, con_id
, idx
, &lookupflags
);
3649 dev_dbg(dev
, "lookup for GPIO %s failed\n", con_id
);
3654 * If a connection label was passed use that, else attempt to use
3655 * the device name as label
3657 status
= gpiod_request(desc
, con_id
? con_id
: devname
);
3659 return ERR_PTR(status
);
3661 status
= gpiod_configure_flags(desc
, con_id
, lookupflags
, flags
);
3663 dev_dbg(dev
, "setup of GPIO %s failed\n", con_id
);
3665 return ERR_PTR(status
);
3670 EXPORT_SYMBOL_GPL(gpiod_get_index
);
3673 * fwnode_get_named_gpiod - obtain a GPIO from firmware node
3674 * @fwnode: handle of the firmware node
3675 * @propname: name of the firmware property representing the GPIO
3676 * @index: index of the GPIO to obtain in the consumer
3677 * @dflags: GPIO initialization flags
3678 * @label: label to attach to the requested GPIO
3680 * This function can be used for drivers that get their configuration
3683 * Function properly finds the corresponding GPIO using whatever is the
3684 * underlying firmware interface and then makes sure that the GPIO
3685 * descriptor is requested before it is returned to the caller.
3688 * On successful request the GPIO pin is configured in accordance with
3691 * In case of error an ERR_PTR() is returned.
3693 struct gpio_desc
*fwnode_get_named_gpiod(struct fwnode_handle
*fwnode
,
3694 const char *propname
, int index
,
3695 enum gpiod_flags dflags
,
3698 struct gpio_desc
*desc
= ERR_PTR(-ENODEV
);
3699 unsigned long lflags
= 0;
3700 bool active_low
= false;
3701 bool single_ended
= false;
3702 bool open_drain
= false;
3706 return ERR_PTR(-EINVAL
);
3708 if (is_of_node(fwnode
)) {
3709 enum of_gpio_flags flags
;
3711 desc
= of_get_named_gpiod_flags(to_of_node(fwnode
), propname
,
3713 if (!IS_ERR(desc
)) {
3714 active_low
= flags
& OF_GPIO_ACTIVE_LOW
;
3715 single_ended
= flags
& OF_GPIO_SINGLE_ENDED
;
3716 open_drain
= flags
& OF_GPIO_OPEN_DRAIN
;
3718 } else if (is_acpi_node(fwnode
)) {
3719 struct acpi_gpio_info info
;
3721 desc
= acpi_node_get_gpiod(fwnode
, propname
, index
, &info
);
3722 if (!IS_ERR(desc
)) {
3723 active_low
= info
.polarity
== GPIO_ACTIVE_LOW
;
3724 ret
= acpi_gpio_update_gpiod_flags(&dflags
, info
.flags
);
3726 pr_debug("Override GPIO initialization flags\n");
3733 ret
= gpiod_request(desc
, label
);
3735 return ERR_PTR(ret
);
3738 lflags
|= GPIO_ACTIVE_LOW
;
3742 lflags
|= GPIO_OPEN_DRAIN
;
3744 lflags
|= GPIO_OPEN_SOURCE
;
3747 ret
= gpiod_configure_flags(desc
, propname
, lflags
, dflags
);
3750 return ERR_PTR(ret
);
3755 EXPORT_SYMBOL_GPL(fwnode_get_named_gpiod
);
3758 * gpiod_get_index_optional - obtain an optional GPIO from a multi-index GPIO
3760 * @dev: GPIO consumer, can be NULL for system-global GPIOs
3761 * @con_id: function within the GPIO consumer
3762 * @index: index of the GPIO to obtain in the consumer
3763 * @flags: optional GPIO initialization flags
3765 * This is equivalent to gpiod_get_index(), except that when no GPIO with the
3766 * specified index was assigned to the requested function it will return NULL.
3767 * This is convenient for drivers that need to handle optional GPIOs.
3769 struct gpio_desc
*__must_check
gpiod_get_index_optional(struct device
*dev
,
3772 enum gpiod_flags flags
)
3774 struct gpio_desc
*desc
;
3776 desc
= gpiod_get_index(dev
, con_id
, index
, flags
);
3778 if (PTR_ERR(desc
) == -ENOENT
)
3784 EXPORT_SYMBOL_GPL(gpiod_get_index_optional
);
3787 * gpiod_hog - Hog the specified GPIO desc given the provided flags
3788 * @desc: gpio whose value will be assigned
3789 * @name: gpio line name
3790 * @lflags: gpio_lookup_flags - returned from of_find_gpio() or
3792 * @dflags: gpiod_flags - optional GPIO initialization flags
3794 int gpiod_hog(struct gpio_desc
*desc
, const char *name
,
3795 unsigned long lflags
, enum gpiod_flags dflags
)
3797 struct gpio_chip
*chip
;
3798 struct gpio_desc
*local_desc
;
3802 chip
= gpiod_to_chip(desc
);
3803 hwnum
= gpio_chip_hwgpio(desc
);
3805 local_desc
= gpiochip_request_own_desc(chip
, hwnum
, name
);
3806 if (IS_ERR(local_desc
)) {
3807 status
= PTR_ERR(local_desc
);
3808 pr_err("requesting hog GPIO %s (chip %s, offset %d) failed, %d\n",
3809 name
, chip
->label
, hwnum
, status
);
3813 status
= gpiod_configure_flags(desc
, name
, lflags
, dflags
);
3815 pr_err("setup of hog GPIO %s (chip %s, offset %d) failed, %d\n",
3816 name
, chip
->label
, hwnum
, status
);
3817 gpiochip_free_own_desc(desc
);
3821 /* Mark GPIO as hogged so it can be identified and removed later */
3822 set_bit(FLAG_IS_HOGGED
, &desc
->flags
);
3824 pr_info("GPIO line %d (%s) hogged as %s%s\n",
3825 desc_to_gpio(desc
), name
,
3826 (dflags
&GPIOD_FLAGS_BIT_DIR_OUT
) ? "output" : "input",
3827 (dflags
&GPIOD_FLAGS_BIT_DIR_OUT
) ?
3828 (dflags
&GPIOD_FLAGS_BIT_DIR_VAL
) ? "/high" : "/low":"");
3834 * gpiochip_free_hogs - Scan gpio-controller chip and release GPIO hog
3835 * @chip: gpio chip to act on
3837 * This is only used by of_gpiochip_remove to free hogged gpios
3839 static void gpiochip_free_hogs(struct gpio_chip
*chip
)
3843 for (id
= 0; id
< chip
->ngpio
; id
++) {
3844 if (test_bit(FLAG_IS_HOGGED
, &chip
->gpiodev
->descs
[id
].flags
))
3845 gpiochip_free_own_desc(&chip
->gpiodev
->descs
[id
]);
3850 * gpiod_get_array - obtain multiple GPIOs from a multi-index GPIO function
3851 * @dev: GPIO consumer, can be NULL for system-global GPIOs
3852 * @con_id: function within the GPIO consumer
3853 * @flags: optional GPIO initialization flags
3855 * This function acquires all the GPIOs defined under a given function.
3857 * Return a struct gpio_descs containing an array of descriptors, -ENOENT if
3858 * no GPIO has been assigned to the requested function, or another IS_ERR()
3859 * code if an error occurred while trying to acquire the GPIOs.
3861 struct gpio_descs
*__must_check
gpiod_get_array(struct device
*dev
,
3863 enum gpiod_flags flags
)
3865 struct gpio_desc
*desc
;
3866 struct gpio_descs
*descs
;
3869 count
= gpiod_count(dev
, con_id
);
3871 return ERR_PTR(count
);
3873 descs
= kzalloc(sizeof(*descs
) + sizeof(descs
->desc
[0]) * count
,
3876 return ERR_PTR(-ENOMEM
);
3878 for (descs
->ndescs
= 0; descs
->ndescs
< count
; ) {
3879 desc
= gpiod_get_index(dev
, con_id
, descs
->ndescs
, flags
);
3881 gpiod_put_array(descs
);
3882 return ERR_CAST(desc
);
3884 descs
->desc
[descs
->ndescs
] = desc
;
3889 EXPORT_SYMBOL_GPL(gpiod_get_array
);
3892 * gpiod_get_array_optional - obtain multiple GPIOs from a multi-index GPIO
3894 * @dev: GPIO consumer, can be NULL for system-global GPIOs
3895 * @con_id: function within the GPIO consumer
3896 * @flags: optional GPIO initialization flags
3898 * This is equivalent to gpiod_get_array(), except that when no GPIO was
3899 * assigned to the requested function it will return NULL.
3901 struct gpio_descs
*__must_check
gpiod_get_array_optional(struct device
*dev
,
3903 enum gpiod_flags flags
)
3905 struct gpio_descs
*descs
;
3907 descs
= gpiod_get_array(dev
, con_id
, flags
);
3908 if (IS_ERR(descs
) && (PTR_ERR(descs
) == -ENOENT
))
3913 EXPORT_SYMBOL_GPL(gpiod_get_array_optional
);
3916 * gpiod_put - dispose of a GPIO descriptor
3917 * @desc: GPIO descriptor to dispose of
3919 * No descriptor can be used after gpiod_put() has been called on it.
3921 void gpiod_put(struct gpio_desc
*desc
)
3925 EXPORT_SYMBOL_GPL(gpiod_put
);
3928 * gpiod_put_array - dispose of multiple GPIO descriptors
3929 * @descs: struct gpio_descs containing an array of descriptors
3931 void gpiod_put_array(struct gpio_descs
*descs
)
3935 for (i
= 0; i
< descs
->ndescs
; i
++)
3936 gpiod_put(descs
->desc
[i
]);
3940 EXPORT_SYMBOL_GPL(gpiod_put_array
);
3942 static int __init
gpiolib_dev_init(void)
3946 /* Register GPIO sysfs bus */
3947 ret
= bus_register(&gpio_bus_type
);
3949 pr_err("gpiolib: could not register GPIO bus type\n");
3953 ret
= alloc_chrdev_region(&gpio_devt
, 0, GPIO_DEV_MAX
, "gpiochip");
3955 pr_err("gpiolib: failed to allocate char dev region\n");
3956 bus_unregister(&gpio_bus_type
);
3958 gpiolib_initialized
= true;
3959 gpiochip_setup_devs();
3963 core_initcall(gpiolib_dev_init
);
3965 #ifdef CONFIG_DEBUG_FS
3967 static void gpiolib_dbg_show(struct seq_file
*s
, struct gpio_device
*gdev
)
3970 struct gpio_chip
*chip
= gdev
->chip
;
3971 unsigned gpio
= gdev
->base
;
3972 struct gpio_desc
*gdesc
= &gdev
->descs
[0];
3976 for (i
= 0; i
< gdev
->ngpio
; i
++, gpio
++, gdesc
++) {
3977 if (!test_bit(FLAG_REQUESTED
, &gdesc
->flags
)) {
3979 seq_printf(s
, " gpio-%-3d (%-20.20s)\n",
3985 gpiod_get_direction(gdesc
);
3986 is_out
= test_bit(FLAG_IS_OUT
, &gdesc
->flags
);
3987 is_irq
= test_bit(FLAG_USED_AS_IRQ
, &gdesc
->flags
);
3988 seq_printf(s
, " gpio-%-3d (%-20.20s|%-20.20s) %s %s %s",
3989 gpio
, gdesc
->name
? gdesc
->name
: "", gdesc
->label
,
3990 is_out
? "out" : "in ",
3992 ? (chip
->get(chip
, i
) ? "hi" : "lo")
3994 is_irq
? "IRQ" : " ");
3995 seq_printf(s
, "\n");
3999 static void *gpiolib_seq_start(struct seq_file
*s
, loff_t
*pos
)
4001 unsigned long flags
;
4002 struct gpio_device
*gdev
= NULL
;
4003 loff_t index
= *pos
;
4007 spin_lock_irqsave(&gpio_lock
, flags
);
4008 list_for_each_entry(gdev
, &gpio_devices
, list
)
4010 spin_unlock_irqrestore(&gpio_lock
, flags
);
4013 spin_unlock_irqrestore(&gpio_lock
, flags
);
4018 static void *gpiolib_seq_next(struct seq_file
*s
, void *v
, loff_t
*pos
)
4020 unsigned long flags
;
4021 struct gpio_device
*gdev
= v
;
4024 spin_lock_irqsave(&gpio_lock
, flags
);
4025 if (list_is_last(&gdev
->list
, &gpio_devices
))
4028 ret
= list_entry(gdev
->list
.next
, struct gpio_device
, list
);
4029 spin_unlock_irqrestore(&gpio_lock
, flags
);
4037 static void gpiolib_seq_stop(struct seq_file
*s
, void *v
)
4041 static int gpiolib_seq_show(struct seq_file
*s
, void *v
)
4043 struct gpio_device
*gdev
= v
;
4044 struct gpio_chip
*chip
= gdev
->chip
;
4045 struct device
*parent
;
4048 seq_printf(s
, "%s%s: (dangling chip)", (char *)s
->private,
4049 dev_name(&gdev
->dev
));
4053 seq_printf(s
, "%s%s: GPIOs %d-%d", (char *)s
->private,
4054 dev_name(&gdev
->dev
),
4055 gdev
->base
, gdev
->base
+ gdev
->ngpio
- 1);
4056 parent
= chip
->parent
;
4058 seq_printf(s
, ", parent: %s/%s",
4059 parent
->bus
? parent
->bus
->name
: "no-bus",
4062 seq_printf(s
, ", %s", chip
->label
);
4063 if (chip
->can_sleep
)
4064 seq_printf(s
, ", can sleep");
4065 seq_printf(s
, ":\n");
4068 chip
->dbg_show(s
, chip
);
4070 gpiolib_dbg_show(s
, gdev
);
4075 static const struct seq_operations gpiolib_seq_ops
= {
4076 .start
= gpiolib_seq_start
,
4077 .next
= gpiolib_seq_next
,
4078 .stop
= gpiolib_seq_stop
,
4079 .show
= gpiolib_seq_show
,
4082 static int gpiolib_open(struct inode
*inode
, struct file
*file
)
4084 return seq_open(file
, &gpiolib_seq_ops
);
4087 static const struct file_operations gpiolib_operations
= {
4088 .owner
= THIS_MODULE
,
4089 .open
= gpiolib_open
,
4091 .llseek
= seq_lseek
,
4092 .release
= seq_release
,
4095 static int __init
gpiolib_debugfs_init(void)
4097 /* /sys/kernel/debug/gpio */
4098 (void) debugfs_create_file("gpio", S_IFREG
| S_IRUGO
,
4099 NULL
, NULL
, &gpiolib_operations
);
4102 subsys_initcall(gpiolib_debugfs_init
);
4104 #endif /* DEBUG_FS */