1 // SPDX-License-Identifier: GPL-2.0
2 #include <linux/bitmap.h>
3 #include <linux/kernel.h>
4 #include <linux/module.h>
5 #include <linux/interrupt.h>
7 #include <linux/spinlock.h>
8 #include <linux/list.h>
9 #include <linux/device.h>
10 #include <linux/err.h>
11 #include <linux/debugfs.h>
12 #include <linux/seq_file.h>
13 #include <linux/gpio.h>
14 #include <linux/of_gpio.h>
15 #include <linux/idr.h>
16 #include <linux/slab.h>
17 #include <linux/acpi.h>
18 #include <linux/gpio/driver.h>
19 #include <linux/gpio/machine.h>
20 #include <linux/pinctrl/consumer.h>
21 #include <linux/cdev.h>
23 #include <linux/uaccess.h>
24 #include <linux/compat.h>
25 #include <linux/anon_inodes.h>
26 #include <linux/file.h>
27 #include <linux/kfifo.h>
28 #include <linux/poll.h>
29 #include <linux/timekeeping.h>
30 #include <uapi/linux/gpio.h>
34 #define CREATE_TRACE_POINTS
35 #include <trace/events/gpio.h>
37 /* Implementation infrastructure for GPIO interfaces.
39 * The GPIO programming interface allows for inlining speed-critical
40 * get/set operations for common cases, so that access to SOC-integrated
41 * GPIOs can sometimes cost only an instruction or two per bit.
45 /* When debugging, extend minimal trust to callers and platform code.
46 * Also emit diagnostic messages that may help initial bringup, when
47 * board setup or driver bugs are most common.
49 * Otherwise, minimize overhead in what may be bitbanging codepaths.
52 #define extra_checks 1
54 #define extra_checks 0
57 /* Device and char device-related information */
58 static DEFINE_IDA(gpio_ida
);
59 static dev_t gpio_devt
;
60 #define GPIO_DEV_MAX 256 /* 256 GPIO chip devices supported */
61 static struct bus_type gpio_bus_type
= {
66 * Number of GPIOs to use for the fast path in set array
68 #define FASTPATH_NGPIO CONFIG_GPIOLIB_FASTPATH_LIMIT
70 /* gpio_lock prevents conflicts during gpio_desc[] table updates.
71 * While any GPIO is requested, its gpio_chip is not removable;
72 * each GPIO's "requested" flag serves as a lock and refcount.
74 DEFINE_SPINLOCK(gpio_lock
);
76 static DEFINE_MUTEX(gpio_lookup_lock
);
77 static LIST_HEAD(gpio_lookup_list
);
78 LIST_HEAD(gpio_devices
);
80 static DEFINE_MUTEX(gpio_machine_hogs_mutex
);
81 static LIST_HEAD(gpio_machine_hogs
);
83 static void gpiochip_free_hogs(struct gpio_chip
*chip
);
84 static int gpiochip_add_irqchip(struct gpio_chip
*gpiochip
,
85 struct lock_class_key
*lock_key
,
86 struct lock_class_key
*request_key
);
87 static void gpiochip_irqchip_remove(struct gpio_chip
*gpiochip
);
88 static int gpiochip_irqchip_init_valid_mask(struct gpio_chip
*gpiochip
);
89 static void gpiochip_irqchip_free_valid_mask(struct gpio_chip
*gpiochip
);
91 static bool gpiolib_initialized
;
93 static inline void desc_set_label(struct gpio_desc
*d
, const char *label
)
99 * gpio_to_desc - Convert a GPIO number to its descriptor
100 * @gpio: global GPIO number
103 * The GPIO descriptor associated with the given GPIO, or %NULL if no GPIO
104 * with the given number exists in the system.
106 struct gpio_desc
*gpio_to_desc(unsigned gpio
)
108 struct gpio_device
*gdev
;
111 spin_lock_irqsave(&gpio_lock
, flags
);
113 list_for_each_entry(gdev
, &gpio_devices
, list
) {
114 if (gdev
->base
<= gpio
&&
115 gdev
->base
+ gdev
->ngpio
> gpio
) {
116 spin_unlock_irqrestore(&gpio_lock
, flags
);
117 return &gdev
->descs
[gpio
- gdev
->base
];
121 spin_unlock_irqrestore(&gpio_lock
, flags
);
123 if (!gpio_is_valid(gpio
))
124 WARN(1, "invalid GPIO %d\n", gpio
);
128 EXPORT_SYMBOL_GPL(gpio_to_desc
);
131 * gpiochip_get_desc - get the GPIO descriptor corresponding to the given
132 * hardware number for this chip
134 * @hwnum: hardware number of the GPIO for this chip
137 * A pointer to the GPIO descriptor or %ERR_PTR(-EINVAL) if no GPIO exists
138 * in the given chip for the specified hardware number.
140 struct gpio_desc
*gpiochip_get_desc(struct gpio_chip
*chip
,
143 struct gpio_device
*gdev
= chip
->gpiodev
;
145 if (hwnum
>= gdev
->ngpio
)
146 return ERR_PTR(-EINVAL
);
148 return &gdev
->descs
[hwnum
];
152 * desc_to_gpio - convert a GPIO descriptor to the integer namespace
153 * @desc: GPIO descriptor
155 * This should disappear in the future but is needed since we still
156 * use GPIO numbers for error messages and sysfs nodes.
159 * The global GPIO number for the GPIO specified by its descriptor.
161 int desc_to_gpio(const struct gpio_desc
*desc
)
163 return desc
->gdev
->base
+ (desc
- &desc
->gdev
->descs
[0]);
165 EXPORT_SYMBOL_GPL(desc_to_gpio
);
169 * gpiod_to_chip - Return the GPIO chip to which a GPIO descriptor belongs
170 * @desc: descriptor to return the chip of
172 struct gpio_chip
*gpiod_to_chip(const struct gpio_desc
*desc
)
174 if (!desc
|| !desc
->gdev
)
176 return desc
->gdev
->chip
;
178 EXPORT_SYMBOL_GPL(gpiod_to_chip
);
180 /* dynamic allocation of GPIOs, e.g. on a hotplugged device */
181 static int gpiochip_find_base(int ngpio
)
183 struct gpio_device
*gdev
;
184 int base
= ARCH_NR_GPIOS
- ngpio
;
186 list_for_each_entry_reverse(gdev
, &gpio_devices
, list
) {
187 /* found a free space? */
188 if (gdev
->base
+ gdev
->ngpio
<= base
)
191 /* nope, check the space right before the chip */
192 base
= gdev
->base
- ngpio
;
195 if (gpio_is_valid(base
)) {
196 pr_debug("%s: found new base at %d\n", __func__
, base
);
199 pr_err("%s: cannot find free range\n", __func__
);
205 * gpiod_get_direction - return the current direction of a GPIO
206 * @desc: GPIO to get the direction of
208 * Returns 0 for output, 1 for input, or an error code in case of error.
210 * This function may sleep if gpiod_cansleep() is true.
212 int gpiod_get_direction(struct gpio_desc
*desc
)
214 struct gpio_chip
*chip
;
218 chip
= gpiod_to_chip(desc
);
219 offset
= gpio_chip_hwgpio(desc
);
221 if (!chip
->get_direction
)
224 status
= chip
->get_direction(chip
, offset
);
226 /* GPIOF_DIR_IN, or other positive */
228 clear_bit(FLAG_IS_OUT
, &desc
->flags
);
232 set_bit(FLAG_IS_OUT
, &desc
->flags
);
236 EXPORT_SYMBOL_GPL(gpiod_get_direction
);
239 * Add a new chip to the global chips list, keeping the list of chips sorted
240 * by range(means [base, base + ngpio - 1]) order.
242 * Return -EBUSY if the new chip overlaps with some other chip's integer
245 static int gpiodev_add_to_list(struct gpio_device
*gdev
)
247 struct gpio_device
*prev
, *next
;
249 if (list_empty(&gpio_devices
)) {
250 /* initial entry in list */
251 list_add_tail(&gdev
->list
, &gpio_devices
);
255 next
= list_entry(gpio_devices
.next
, struct gpio_device
, list
);
256 if (gdev
->base
+ gdev
->ngpio
<= next
->base
) {
257 /* add before first entry */
258 list_add(&gdev
->list
, &gpio_devices
);
262 prev
= list_entry(gpio_devices
.prev
, struct gpio_device
, list
);
263 if (prev
->base
+ prev
->ngpio
<= gdev
->base
) {
264 /* add behind last entry */
265 list_add_tail(&gdev
->list
, &gpio_devices
);
269 list_for_each_entry_safe(prev
, next
, &gpio_devices
, list
) {
270 /* at the end of the list */
271 if (&next
->list
== &gpio_devices
)
274 /* add between prev and next */
275 if (prev
->base
+ prev
->ngpio
<= gdev
->base
276 && gdev
->base
+ gdev
->ngpio
<= next
->base
) {
277 list_add(&gdev
->list
, &prev
->list
);
282 dev_err(&gdev
->dev
, "GPIO integer space overlap, cannot add chip\n");
287 * Convert a GPIO name to its descriptor
289 static struct gpio_desc
*gpio_name_to_desc(const char * const name
)
291 struct gpio_device
*gdev
;
294 spin_lock_irqsave(&gpio_lock
, flags
);
296 list_for_each_entry(gdev
, &gpio_devices
, list
) {
299 for (i
= 0; i
!= gdev
->ngpio
; ++i
) {
300 struct gpio_desc
*desc
= &gdev
->descs
[i
];
302 if (!desc
->name
|| !name
)
305 if (!strcmp(desc
->name
, name
)) {
306 spin_unlock_irqrestore(&gpio_lock
, flags
);
312 spin_unlock_irqrestore(&gpio_lock
, flags
);
318 * Takes the names from gc->names and checks if they are all unique. If they
319 * are, they are assigned to their gpio descriptors.
321 * Warning if one of the names is already used for a different GPIO.
323 static int gpiochip_set_desc_names(struct gpio_chip
*gc
)
325 struct gpio_device
*gdev
= gc
->gpiodev
;
331 /* First check all names if they are unique */
332 for (i
= 0; i
!= gc
->ngpio
; ++i
) {
333 struct gpio_desc
*gpio
;
335 gpio
= gpio_name_to_desc(gc
->names
[i
]);
338 "Detected name collision for GPIO name '%s'\n",
342 /* Then add all names to the GPIO descriptors */
343 for (i
= 0; i
!= gc
->ngpio
; ++i
)
344 gdev
->descs
[i
].name
= gc
->names
[i
];
349 static unsigned long *gpiochip_allocate_mask(struct gpio_chip
*chip
)
353 p
= kmalloc_array(BITS_TO_LONGS(chip
->ngpio
), sizeof(*p
), GFP_KERNEL
);
357 /* Assume by default all GPIOs are valid */
358 bitmap_fill(p
, chip
->ngpio
);
363 static int gpiochip_alloc_valid_mask(struct gpio_chip
*gpiochip
)
365 #ifdef CONFIG_OF_GPIO
367 struct device_node
*np
= gpiochip
->of_node
;
369 size
= of_property_count_u32_elems(np
, "gpio-reserved-ranges");
370 if (size
> 0 && size
% 2 == 0)
371 gpiochip
->need_valid_mask
= true;
374 if (!gpiochip
->need_valid_mask
)
377 gpiochip
->valid_mask
= gpiochip_allocate_mask(gpiochip
);
378 if (!gpiochip
->valid_mask
)
384 static int gpiochip_init_valid_mask(struct gpio_chip
*gpiochip
)
386 if (gpiochip
->init_valid_mask
)
387 return gpiochip
->init_valid_mask(gpiochip
);
392 static void gpiochip_free_valid_mask(struct gpio_chip
*gpiochip
)
394 kfree(gpiochip
->valid_mask
);
395 gpiochip
->valid_mask
= NULL
;
398 bool gpiochip_line_is_valid(const struct gpio_chip
*gpiochip
,
401 /* No mask means all valid */
402 if (likely(!gpiochip
->valid_mask
))
404 return test_bit(offset
, gpiochip
->valid_mask
);
406 EXPORT_SYMBOL_GPL(gpiochip_line_is_valid
);
409 * GPIO line handle management
413 * struct linehandle_state - contains the state of a userspace handle
414 * @gdev: the GPIO device the handle pertains to
415 * @label: consumer label used to tag descriptors
416 * @descs: the GPIO descriptors held by this handle
417 * @numdescs: the number of descriptors held in the descs array
419 struct linehandle_state
{
420 struct gpio_device
*gdev
;
422 struct gpio_desc
*descs
[GPIOHANDLES_MAX
];
426 #define GPIOHANDLE_REQUEST_VALID_FLAGS \
427 (GPIOHANDLE_REQUEST_INPUT | \
428 GPIOHANDLE_REQUEST_OUTPUT | \
429 GPIOHANDLE_REQUEST_ACTIVE_LOW | \
430 GPIOHANDLE_REQUEST_OPEN_DRAIN | \
431 GPIOHANDLE_REQUEST_OPEN_SOURCE)
433 static long linehandle_ioctl(struct file
*filep
, unsigned int cmd
,
436 struct linehandle_state
*lh
= filep
->private_data
;
437 void __user
*ip
= (void __user
*)arg
;
438 struct gpiohandle_data ghd
;
439 DECLARE_BITMAP(vals
, GPIOHANDLES_MAX
);
442 if (cmd
== GPIOHANDLE_GET_LINE_VALUES_IOCTL
) {
443 /* NOTE: It's ok to read values of output lines. */
444 int ret
= gpiod_get_array_value_complex(false,
453 memset(&ghd
, 0, sizeof(ghd
));
454 for (i
= 0; i
< lh
->numdescs
; i
++)
455 ghd
.values
[i
] = test_bit(i
, vals
);
457 if (copy_to_user(ip
, &ghd
, sizeof(ghd
)))
461 } else if (cmd
== GPIOHANDLE_SET_LINE_VALUES_IOCTL
) {
463 * All line descriptors were created at once with the same
464 * flags so just check if the first one is really output.
466 if (!test_bit(FLAG_IS_OUT
, &lh
->descs
[0]->flags
))
469 if (copy_from_user(&ghd
, ip
, sizeof(ghd
)))
472 /* Clamp all values to [0,1] */
473 for (i
= 0; i
< lh
->numdescs
; i
++)
474 __assign_bit(i
, vals
, ghd
.values
[i
]);
476 /* Reuse the array setting function */
477 return gpiod_set_array_value_complex(false,
488 static long linehandle_ioctl_compat(struct file
*filep
, unsigned int cmd
,
491 return linehandle_ioctl(filep
, cmd
, (unsigned long)compat_ptr(arg
));
495 static int linehandle_release(struct inode
*inode
, struct file
*filep
)
497 struct linehandle_state
*lh
= filep
->private_data
;
498 struct gpio_device
*gdev
= lh
->gdev
;
501 for (i
= 0; i
< lh
->numdescs
; i
++)
502 gpiod_free(lh
->descs
[i
]);
505 put_device(&gdev
->dev
);
509 static const struct file_operations linehandle_fileops
= {
510 .release
= linehandle_release
,
511 .owner
= THIS_MODULE
,
512 .llseek
= noop_llseek
,
513 .unlocked_ioctl
= linehandle_ioctl
,
515 .compat_ioctl
= linehandle_ioctl_compat
,
519 static int linehandle_create(struct gpio_device
*gdev
, void __user
*ip
)
521 struct gpiohandle_request handlereq
;
522 struct linehandle_state
*lh
;
524 int fd
, i
, count
= 0, ret
;
527 if (copy_from_user(&handlereq
, ip
, sizeof(handlereq
)))
529 if ((handlereq
.lines
== 0) || (handlereq
.lines
> GPIOHANDLES_MAX
))
532 lflags
= handlereq
.flags
;
534 /* Return an error if an unknown flag is set */
535 if (lflags
& ~GPIOHANDLE_REQUEST_VALID_FLAGS
)
539 * Do not allow OPEN_SOURCE & OPEN_DRAIN flags in a single request. If
540 * the hardware actually supports enabling both at the same time the
541 * electrical result would be disastrous.
543 if ((lflags
& GPIOHANDLE_REQUEST_OPEN_DRAIN
) &&
544 (lflags
& GPIOHANDLE_REQUEST_OPEN_SOURCE
))
547 /* OPEN_DRAIN and OPEN_SOURCE flags only make sense for output mode. */
548 if (!(lflags
& GPIOHANDLE_REQUEST_OUTPUT
) &&
549 ((lflags
& GPIOHANDLE_REQUEST_OPEN_DRAIN
) ||
550 (lflags
& GPIOHANDLE_REQUEST_OPEN_SOURCE
)))
553 lh
= kzalloc(sizeof(*lh
), GFP_KERNEL
);
557 get_device(&gdev
->dev
);
559 /* Make sure this is terminated */
560 handlereq
.consumer_label
[sizeof(handlereq
.consumer_label
)-1] = '\0';
561 if (strlen(handlereq
.consumer_label
)) {
562 lh
->label
= kstrdup(handlereq
.consumer_label
,
570 /* Request each GPIO */
571 for (i
= 0; i
< handlereq
.lines
; i
++) {
572 u32 offset
= handlereq
.lineoffsets
[i
];
573 struct gpio_desc
*desc
;
575 if (offset
>= gdev
->ngpio
) {
580 desc
= &gdev
->descs
[offset
];
581 ret
= gpiod_request(desc
, lh
->label
);
587 if (lflags
& GPIOHANDLE_REQUEST_ACTIVE_LOW
)
588 set_bit(FLAG_ACTIVE_LOW
, &desc
->flags
);
589 if (lflags
& GPIOHANDLE_REQUEST_OPEN_DRAIN
)
590 set_bit(FLAG_OPEN_DRAIN
, &desc
->flags
);
591 if (lflags
& GPIOHANDLE_REQUEST_OPEN_SOURCE
)
592 set_bit(FLAG_OPEN_SOURCE
, &desc
->flags
);
594 ret
= gpiod_set_transitory(desc
, false);
599 * Lines have to be requested explicitly for input
600 * or output, else the line will be treated "as is".
602 if (lflags
& GPIOHANDLE_REQUEST_OUTPUT
) {
603 int val
= !!handlereq
.default_values
[i
];
605 ret
= gpiod_direction_output(desc
, val
);
608 } else if (lflags
& GPIOHANDLE_REQUEST_INPUT
) {
609 ret
= gpiod_direction_input(desc
);
613 dev_dbg(&gdev
->dev
, "registered chardev handle for line %d\n",
616 /* Let i point at the last handle */
618 lh
->numdescs
= handlereq
.lines
;
620 fd
= get_unused_fd_flags(O_RDONLY
| O_CLOEXEC
);
626 file
= anon_inode_getfile("gpio-linehandle",
629 O_RDONLY
| O_CLOEXEC
);
632 goto out_put_unused_fd
;
636 if (copy_to_user(ip
, &handlereq
, sizeof(handlereq
))) {
638 * fput() will trigger the release() callback, so do not go onto
639 * the regular error cleanup path here.
646 fd_install(fd
, file
);
648 dev_dbg(&gdev
->dev
, "registered chardev handle for %d lines\n",
656 for (i
= 0; i
< count
; i
++)
657 gpiod_free(lh
->descs
[i
]);
661 put_device(&gdev
->dev
);
666 * GPIO line event management
670 * struct lineevent_state - contains the state of a userspace event
671 * @gdev: the GPIO device the event pertains to
672 * @label: consumer label used to tag descriptors
673 * @desc: the GPIO descriptor held by this event
674 * @eflags: the event flags this line was requested with
675 * @irq: the interrupt that trigger in response to events on this GPIO
676 * @wait: wait queue that handles blocking reads of events
677 * @events: KFIFO for the GPIO events
678 * @read_lock: mutex lock to protect reads from colliding with adding
679 * new events to the FIFO
680 * @timestamp: cache for the timestamp storing it between hardirq
681 * and IRQ thread, used to bring the timestamp close to the actual
684 struct lineevent_state
{
685 struct gpio_device
*gdev
;
687 struct gpio_desc
*desc
;
690 wait_queue_head_t wait
;
691 DECLARE_KFIFO(events
, struct gpioevent_data
, 16);
692 struct mutex read_lock
;
696 #define GPIOEVENT_REQUEST_VALID_FLAGS \
697 (GPIOEVENT_REQUEST_RISING_EDGE | \
698 GPIOEVENT_REQUEST_FALLING_EDGE)
700 static __poll_t
lineevent_poll(struct file
*filep
,
701 struct poll_table_struct
*wait
)
703 struct lineevent_state
*le
= filep
->private_data
;
706 poll_wait(filep
, &le
->wait
, wait
);
708 if (!kfifo_is_empty(&le
->events
))
709 events
= EPOLLIN
| EPOLLRDNORM
;
715 static ssize_t
lineevent_read(struct file
*filep
,
720 struct lineevent_state
*le
= filep
->private_data
;
724 if (count
< sizeof(struct gpioevent_data
))
728 if (kfifo_is_empty(&le
->events
)) {
729 if (filep
->f_flags
& O_NONBLOCK
)
732 ret
= wait_event_interruptible(le
->wait
,
733 !kfifo_is_empty(&le
->events
));
738 if (mutex_lock_interruptible(&le
->read_lock
))
740 ret
= kfifo_to_user(&le
->events
, buf
, count
, &copied
);
741 mutex_unlock(&le
->read_lock
);
747 * If we couldn't read anything from the fifo (a different
748 * thread might have been faster) we either return -EAGAIN if
749 * the file descriptor is non-blocking, otherwise we go back to
750 * sleep and wait for more data to arrive.
752 if (copied
== 0 && (filep
->f_flags
& O_NONBLOCK
))
755 } while (copied
== 0);
760 static int lineevent_release(struct inode
*inode
, struct file
*filep
)
762 struct lineevent_state
*le
= filep
->private_data
;
763 struct gpio_device
*gdev
= le
->gdev
;
765 free_irq(le
->irq
, le
);
766 gpiod_free(le
->desc
);
769 put_device(&gdev
->dev
);
773 static long lineevent_ioctl(struct file
*filep
, unsigned int cmd
,
776 struct lineevent_state
*le
= filep
->private_data
;
777 void __user
*ip
= (void __user
*)arg
;
778 struct gpiohandle_data ghd
;
781 * We can get the value for an event line but not set it,
782 * because it is input by definition.
784 if (cmd
== GPIOHANDLE_GET_LINE_VALUES_IOCTL
) {
787 memset(&ghd
, 0, sizeof(ghd
));
789 val
= gpiod_get_value_cansleep(le
->desc
);
794 if (copy_to_user(ip
, &ghd
, sizeof(ghd
)))
803 static long lineevent_ioctl_compat(struct file
*filep
, unsigned int cmd
,
806 return lineevent_ioctl(filep
, cmd
, (unsigned long)compat_ptr(arg
));
810 static const struct file_operations lineevent_fileops
= {
811 .release
= lineevent_release
,
812 .read
= lineevent_read
,
813 .poll
= lineevent_poll
,
814 .owner
= THIS_MODULE
,
815 .llseek
= noop_llseek
,
816 .unlocked_ioctl
= lineevent_ioctl
,
818 .compat_ioctl
= lineevent_ioctl_compat
,
822 static irqreturn_t
lineevent_irq_thread(int irq
, void *p
)
824 struct lineevent_state
*le
= p
;
825 struct gpioevent_data ge
;
828 /* Do not leak kernel stack to userspace */
829 memset(&ge
, 0, sizeof(ge
));
831 ge
.timestamp
= le
->timestamp
;
833 if (le
->eflags
& GPIOEVENT_REQUEST_RISING_EDGE
834 && le
->eflags
& GPIOEVENT_REQUEST_FALLING_EDGE
) {
835 int level
= gpiod_get_value_cansleep(le
->desc
);
837 /* Emit low-to-high event */
838 ge
.id
= GPIOEVENT_EVENT_RISING_EDGE
;
840 /* Emit high-to-low event */
841 ge
.id
= GPIOEVENT_EVENT_FALLING_EDGE
;
842 } else if (le
->eflags
& GPIOEVENT_REQUEST_RISING_EDGE
) {
843 /* Emit low-to-high event */
844 ge
.id
= GPIOEVENT_EVENT_RISING_EDGE
;
845 } else if (le
->eflags
& GPIOEVENT_REQUEST_FALLING_EDGE
) {
846 /* Emit high-to-low event */
847 ge
.id
= GPIOEVENT_EVENT_FALLING_EDGE
;
852 ret
= kfifo_put(&le
->events
, ge
);
854 wake_up_poll(&le
->wait
, EPOLLIN
);
859 static irqreturn_t
lineevent_irq_handler(int irq
, void *p
)
861 struct lineevent_state
*le
= p
;
864 * Just store the timestamp in hardirq context so we get it as
865 * close in time as possible to the actual event.
867 le
->timestamp
= ktime_get_real_ns();
869 return IRQ_WAKE_THREAD
;
872 static int lineevent_create(struct gpio_device
*gdev
, void __user
*ip
)
874 struct gpioevent_request eventreq
;
875 struct lineevent_state
*le
;
876 struct gpio_desc
*desc
;
885 if (copy_from_user(&eventreq
, ip
, sizeof(eventreq
)))
888 le
= kzalloc(sizeof(*le
), GFP_KERNEL
);
892 get_device(&gdev
->dev
);
894 /* Make sure this is terminated */
895 eventreq
.consumer_label
[sizeof(eventreq
.consumer_label
)-1] = '\0';
896 if (strlen(eventreq
.consumer_label
)) {
897 le
->label
= kstrdup(eventreq
.consumer_label
,
905 offset
= eventreq
.lineoffset
;
906 lflags
= eventreq
.handleflags
;
907 eflags
= eventreq
.eventflags
;
909 if (offset
>= gdev
->ngpio
) {
914 /* Return an error if a unknown flag is set */
915 if ((lflags
& ~GPIOHANDLE_REQUEST_VALID_FLAGS
) ||
916 (eflags
& ~GPIOEVENT_REQUEST_VALID_FLAGS
)) {
921 /* This is just wrong: we don't look for events on output lines */
922 if (lflags
& GPIOHANDLE_REQUEST_OUTPUT
) {
927 desc
= &gdev
->descs
[offset
];
928 ret
= gpiod_request(desc
, le
->label
);
934 if (lflags
& GPIOHANDLE_REQUEST_ACTIVE_LOW
)
935 set_bit(FLAG_ACTIVE_LOW
, &desc
->flags
);
936 if (lflags
& GPIOHANDLE_REQUEST_OPEN_DRAIN
)
937 set_bit(FLAG_OPEN_DRAIN
, &desc
->flags
);
938 if (lflags
& GPIOHANDLE_REQUEST_OPEN_SOURCE
)
939 set_bit(FLAG_OPEN_SOURCE
, &desc
->flags
);
941 ret
= gpiod_direction_input(desc
);
945 le
->irq
= gpiod_to_irq(desc
);
951 if (eflags
& GPIOEVENT_REQUEST_RISING_EDGE
)
952 irqflags
|= IRQF_TRIGGER_RISING
;
953 if (eflags
& GPIOEVENT_REQUEST_FALLING_EDGE
)
954 irqflags
|= IRQF_TRIGGER_FALLING
;
955 irqflags
|= IRQF_ONESHOT
;
957 INIT_KFIFO(le
->events
);
958 init_waitqueue_head(&le
->wait
);
959 mutex_init(&le
->read_lock
);
961 /* Request a thread to read the events */
962 ret
= request_threaded_irq(le
->irq
,
963 lineevent_irq_handler
,
964 lineevent_irq_thread
,
971 fd
= get_unused_fd_flags(O_RDONLY
| O_CLOEXEC
);
977 file
= anon_inode_getfile("gpio-event",
980 O_RDONLY
| O_CLOEXEC
);
983 goto out_put_unused_fd
;
987 if (copy_to_user(ip
, &eventreq
, sizeof(eventreq
))) {
989 * fput() will trigger the release() callback, so do not go onto
990 * the regular error cleanup path here.
997 fd_install(fd
, file
);
1004 free_irq(le
->irq
, le
);
1006 gpiod_free(le
->desc
);
1011 put_device(&gdev
->dev
);
1016 * gpio_ioctl() - ioctl handler for the GPIO chardev
1018 static long gpio_ioctl(struct file
*filp
, unsigned int cmd
, unsigned long arg
)
1020 struct gpio_device
*gdev
= filp
->private_data
;
1021 struct gpio_chip
*chip
= gdev
->chip
;
1022 void __user
*ip
= (void __user
*)arg
;
1024 /* We fail any subsequent ioctl():s when the chip is gone */
1028 /* Fill in the struct and pass to userspace */
1029 if (cmd
== GPIO_GET_CHIPINFO_IOCTL
) {
1030 struct gpiochip_info chipinfo
;
1032 memset(&chipinfo
, 0, sizeof(chipinfo
));
1034 strncpy(chipinfo
.name
, dev_name(&gdev
->dev
),
1035 sizeof(chipinfo
.name
));
1036 chipinfo
.name
[sizeof(chipinfo
.name
)-1] = '\0';
1037 strncpy(chipinfo
.label
, gdev
->label
,
1038 sizeof(chipinfo
.label
));
1039 chipinfo
.label
[sizeof(chipinfo
.label
)-1] = '\0';
1040 chipinfo
.lines
= gdev
->ngpio
;
1041 if (copy_to_user(ip
, &chipinfo
, sizeof(chipinfo
)))
1044 } else if (cmd
== GPIO_GET_LINEINFO_IOCTL
) {
1045 struct gpioline_info lineinfo
;
1046 struct gpio_desc
*desc
;
1048 if (copy_from_user(&lineinfo
, ip
, sizeof(lineinfo
)))
1050 if (lineinfo
.line_offset
>= gdev
->ngpio
)
1053 desc
= &gdev
->descs
[lineinfo
.line_offset
];
1055 strncpy(lineinfo
.name
, desc
->name
,
1056 sizeof(lineinfo
.name
));
1057 lineinfo
.name
[sizeof(lineinfo
.name
)-1] = '\0';
1059 lineinfo
.name
[0] = '\0';
1062 strncpy(lineinfo
.consumer
, desc
->label
,
1063 sizeof(lineinfo
.consumer
));
1064 lineinfo
.consumer
[sizeof(lineinfo
.consumer
)-1] = '\0';
1066 lineinfo
.consumer
[0] = '\0';
1070 * Userspace only need to know that the kernel is using
1071 * this GPIO so it can't use it.
1074 if (test_bit(FLAG_REQUESTED
, &desc
->flags
) ||
1075 test_bit(FLAG_IS_HOGGED
, &desc
->flags
) ||
1076 test_bit(FLAG_USED_AS_IRQ
, &desc
->flags
) ||
1077 test_bit(FLAG_EXPORT
, &desc
->flags
) ||
1078 test_bit(FLAG_SYSFS
, &desc
->flags
))
1079 lineinfo
.flags
|= GPIOLINE_FLAG_KERNEL
;
1080 if (test_bit(FLAG_IS_OUT
, &desc
->flags
))
1081 lineinfo
.flags
|= GPIOLINE_FLAG_IS_OUT
;
1082 if (test_bit(FLAG_ACTIVE_LOW
, &desc
->flags
))
1083 lineinfo
.flags
|= GPIOLINE_FLAG_ACTIVE_LOW
;
1084 if (test_bit(FLAG_OPEN_DRAIN
, &desc
->flags
))
1085 lineinfo
.flags
|= GPIOLINE_FLAG_OPEN_DRAIN
;
1086 if (test_bit(FLAG_OPEN_SOURCE
, &desc
->flags
))
1087 lineinfo
.flags
|= GPIOLINE_FLAG_OPEN_SOURCE
;
1089 if (copy_to_user(ip
, &lineinfo
, sizeof(lineinfo
)))
1092 } else if (cmd
== GPIO_GET_LINEHANDLE_IOCTL
) {
1093 return linehandle_create(gdev
, ip
);
1094 } else if (cmd
== GPIO_GET_LINEEVENT_IOCTL
) {
1095 return lineevent_create(gdev
, ip
);
1100 #ifdef CONFIG_COMPAT
1101 static long gpio_ioctl_compat(struct file
*filp
, unsigned int cmd
,
1104 return gpio_ioctl(filp
, cmd
, (unsigned long)compat_ptr(arg
));
1109 * gpio_chrdev_open() - open the chardev for ioctl operations
1110 * @inode: inode for this chardev
1111 * @filp: file struct for storing private data
1112 * Returns 0 on success
1114 static int gpio_chrdev_open(struct inode
*inode
, struct file
*filp
)
1116 struct gpio_device
*gdev
= container_of(inode
->i_cdev
,
1117 struct gpio_device
, chrdev
);
1119 /* Fail on open if the backing gpiochip is gone */
1122 get_device(&gdev
->dev
);
1123 filp
->private_data
= gdev
;
1125 return nonseekable_open(inode
, filp
);
1129 * gpio_chrdev_release() - close chardev after ioctl operations
1130 * @inode: inode for this chardev
1131 * @filp: file struct for storing private data
1132 * Returns 0 on success
1134 static int gpio_chrdev_release(struct inode
*inode
, struct file
*filp
)
1136 struct gpio_device
*gdev
= container_of(inode
->i_cdev
,
1137 struct gpio_device
, chrdev
);
1139 put_device(&gdev
->dev
);
1144 static const struct file_operations gpio_fileops
= {
1145 .release
= gpio_chrdev_release
,
1146 .open
= gpio_chrdev_open
,
1147 .owner
= THIS_MODULE
,
1148 .llseek
= no_llseek
,
1149 .unlocked_ioctl
= gpio_ioctl
,
1150 #ifdef CONFIG_COMPAT
1151 .compat_ioctl
= gpio_ioctl_compat
,
1155 static void gpiodevice_release(struct device
*dev
)
1157 struct gpio_device
*gdev
= dev_get_drvdata(dev
);
1159 list_del(&gdev
->list
);
1160 ida_simple_remove(&gpio_ida
, gdev
->id
);
1161 kfree_const(gdev
->label
);
1166 static int gpiochip_setup_dev(struct gpio_device
*gdev
)
1170 cdev_init(&gdev
->chrdev
, &gpio_fileops
);
1171 gdev
->chrdev
.owner
= THIS_MODULE
;
1172 gdev
->dev
.devt
= MKDEV(MAJOR(gpio_devt
), gdev
->id
);
1174 status
= cdev_device_add(&gdev
->chrdev
, &gdev
->dev
);
1178 chip_dbg(gdev
->chip
, "added GPIO chardev (%d:%d)\n",
1179 MAJOR(gpio_devt
), gdev
->id
);
1181 status
= gpiochip_sysfs_register(gdev
);
1183 goto err_remove_device
;
1185 /* From this point, the .release() function cleans up gpio_device */
1186 gdev
->dev
.release
= gpiodevice_release
;
1187 pr_debug("%s: registered GPIOs %d to %d on device: %s (%s)\n",
1188 __func__
, gdev
->base
, gdev
->base
+ gdev
->ngpio
- 1,
1189 dev_name(&gdev
->dev
), gdev
->chip
->label
? : "generic");
1194 cdev_device_del(&gdev
->chrdev
, &gdev
->dev
);
1198 static void gpiochip_machine_hog(struct gpio_chip
*chip
, struct gpiod_hog
*hog
)
1200 struct gpio_desc
*desc
;
1203 desc
= gpiochip_get_desc(chip
, hog
->chip_hwnum
);
1205 pr_err("%s: unable to get GPIO desc: %ld\n",
1206 __func__
, PTR_ERR(desc
));
1210 if (test_bit(FLAG_IS_HOGGED
, &desc
->flags
))
1213 rv
= gpiod_hog(desc
, hog
->line_name
, hog
->lflags
, hog
->dflags
);
1215 pr_err("%s: unable to hog GPIO line (%s:%u): %d\n",
1216 __func__
, chip
->label
, hog
->chip_hwnum
, rv
);
1219 static void machine_gpiochip_add(struct gpio_chip
*chip
)
1221 struct gpiod_hog
*hog
;
1223 mutex_lock(&gpio_machine_hogs_mutex
);
1225 list_for_each_entry(hog
, &gpio_machine_hogs
, list
) {
1226 if (!strcmp(chip
->label
, hog
->chip_label
))
1227 gpiochip_machine_hog(chip
, hog
);
1230 mutex_unlock(&gpio_machine_hogs_mutex
);
1233 static void gpiochip_setup_devs(void)
1235 struct gpio_device
*gdev
;
1238 list_for_each_entry(gdev
, &gpio_devices
, list
) {
1239 err
= gpiochip_setup_dev(gdev
);
1241 pr_err("%s: Failed to initialize gpio device (%d)\n",
1242 dev_name(&gdev
->dev
), err
);
1246 int gpiochip_add_data_with_key(struct gpio_chip
*chip
, void *data
,
1247 struct lock_class_key
*lock_key
,
1248 struct lock_class_key
*request_key
)
1250 unsigned long flags
;
1253 int base
= chip
->base
;
1254 struct gpio_device
*gdev
;
1257 * First: allocate and populate the internal stat container, and
1258 * set up the struct device.
1260 gdev
= kzalloc(sizeof(*gdev
), GFP_KERNEL
);
1263 gdev
->dev
.bus
= &gpio_bus_type
;
1265 chip
->gpiodev
= gdev
;
1267 gdev
->dev
.parent
= chip
->parent
;
1268 gdev
->dev
.of_node
= chip
->parent
->of_node
;
1271 #ifdef CONFIG_OF_GPIO
1272 /* If the gpiochip has an assigned OF node this takes precedence */
1274 gdev
->dev
.of_node
= chip
->of_node
;
1276 chip
->of_node
= gdev
->dev
.of_node
;
1279 gdev
->id
= ida_simple_get(&gpio_ida
, 0, 0, GFP_KERNEL
);
1284 dev_set_name(&gdev
->dev
, "gpiochip%d", gdev
->id
);
1285 device_initialize(&gdev
->dev
);
1286 dev_set_drvdata(&gdev
->dev
, gdev
);
1287 if (chip
->parent
&& chip
->parent
->driver
)
1288 gdev
->owner
= chip
->parent
->driver
->owner
;
1289 else if (chip
->owner
)
1290 /* TODO: remove chip->owner */
1291 gdev
->owner
= chip
->owner
;
1293 gdev
->owner
= THIS_MODULE
;
1295 gdev
->descs
= kcalloc(chip
->ngpio
, sizeof(gdev
->descs
[0]), GFP_KERNEL
);
1301 if (chip
->ngpio
== 0) {
1302 chip_err(chip
, "tried to insert a GPIO chip with zero lines\n");
1304 goto err_free_descs
;
1307 if (chip
->ngpio
> FASTPATH_NGPIO
)
1308 chip_warn(chip
, "line cnt %u is greater than fast path cnt %u\n",
1309 chip
->ngpio
, FASTPATH_NGPIO
);
1311 gdev
->label
= kstrdup_const(chip
->label
?: "unknown", GFP_KERNEL
);
1314 goto err_free_descs
;
1317 gdev
->ngpio
= chip
->ngpio
;
1320 spin_lock_irqsave(&gpio_lock
, flags
);
1323 * TODO: this allocates a Linux GPIO number base in the global
1324 * GPIO numberspace for this chip. In the long run we want to
1325 * get *rid* of this numberspace and use only descriptors, but
1326 * it may be a pipe dream. It will not happen before we get rid
1327 * of the sysfs interface anyways.
1330 base
= gpiochip_find_base(chip
->ngpio
);
1333 spin_unlock_irqrestore(&gpio_lock
, flags
);
1334 goto err_free_label
;
1337 * TODO: it should not be necessary to reflect the assigned
1338 * base outside of the GPIO subsystem. Go over drivers and
1339 * see if anyone makes use of this, else drop this and assign
1346 status
= gpiodev_add_to_list(gdev
);
1348 spin_unlock_irqrestore(&gpio_lock
, flags
);
1349 goto err_free_label
;
1352 spin_unlock_irqrestore(&gpio_lock
, flags
);
1354 for (i
= 0; i
< chip
->ngpio
; i
++)
1355 gdev
->descs
[i
].gdev
= gdev
;
1357 #ifdef CONFIG_PINCTRL
1358 INIT_LIST_HEAD(&gdev
->pin_ranges
);
1361 status
= gpiochip_set_desc_names(chip
);
1363 goto err_remove_from_list
;
1365 status
= gpiochip_irqchip_init_valid_mask(chip
);
1367 goto err_remove_from_list
;
1369 status
= gpiochip_alloc_valid_mask(chip
);
1371 goto err_remove_irqchip_mask
;
1373 status
= gpiochip_add_irqchip(chip
, lock_key
, request_key
);
1375 goto err_remove_chip
;
1377 status
= of_gpiochip_add(chip
);
1379 goto err_remove_chip
;
1381 status
= gpiochip_init_valid_mask(chip
);
1383 goto err_remove_chip
;
1385 for (i
= 0; i
< chip
->ngpio
; i
++) {
1386 struct gpio_desc
*desc
= &gdev
->descs
[i
];
1388 if (chip
->get_direction
&& gpiochip_line_is_valid(chip
, i
))
1389 desc
->flags
= !chip
->get_direction(chip
, i
) ?
1390 (1 << FLAG_IS_OUT
) : 0;
1392 desc
->flags
= !chip
->direction_input
?
1393 (1 << FLAG_IS_OUT
) : 0;
1396 acpi_gpiochip_add(chip
);
1398 machine_gpiochip_add(chip
);
1401 * By first adding the chardev, and then adding the device,
1402 * we get a device node entry in sysfs under
1403 * /sys/bus/gpio/devices/gpiochipN/dev that can be used for
1404 * coldplug of device nodes and other udev business.
1405 * We can do this only if gpiolib has been initialized.
1406 * Otherwise, defer until later.
1408 if (gpiolib_initialized
) {
1409 status
= gpiochip_setup_dev(gdev
);
1411 goto err_remove_chip
;
1416 acpi_gpiochip_remove(chip
);
1417 gpiochip_free_hogs(chip
);
1418 of_gpiochip_remove(chip
);
1419 gpiochip_free_valid_mask(chip
);
1420 err_remove_irqchip_mask
:
1421 gpiochip_irqchip_free_valid_mask(chip
);
1422 err_remove_from_list
:
1423 spin_lock_irqsave(&gpio_lock
, flags
);
1424 list_del(&gdev
->list
);
1425 spin_unlock_irqrestore(&gpio_lock
, flags
);
1427 kfree_const(gdev
->label
);
1431 ida_simple_remove(&gpio_ida
, gdev
->id
);
1433 /* failures here can mean systems won't boot... */
1434 pr_err("%s: GPIOs %d..%d (%s) failed to register, %d\n", __func__
,
1435 gdev
->base
, gdev
->base
+ gdev
->ngpio
- 1,
1436 chip
->label
? : "generic", status
);
1440 EXPORT_SYMBOL_GPL(gpiochip_add_data_with_key
);
1443 * gpiochip_get_data() - get per-subdriver data for the chip
1447 * The per-subdriver data for the chip.
1449 void *gpiochip_get_data(struct gpio_chip
*chip
)
1451 return chip
->gpiodev
->data
;
1453 EXPORT_SYMBOL_GPL(gpiochip_get_data
);
1456 * gpiochip_remove() - unregister a gpio_chip
1457 * @chip: the chip to unregister
1459 * A gpio_chip with any GPIOs still requested may not be removed.
1461 void gpiochip_remove(struct gpio_chip
*chip
)
1463 struct gpio_device
*gdev
= chip
->gpiodev
;
1464 struct gpio_desc
*desc
;
1465 unsigned long flags
;
1467 bool requested
= false;
1469 /* FIXME: should the legacy sysfs handling be moved to gpio_device? */
1470 gpiochip_sysfs_unregister(gdev
);
1471 gpiochip_free_hogs(chip
);
1472 /* Numb the device, cancelling all outstanding operations */
1474 gpiochip_irqchip_remove(chip
);
1475 acpi_gpiochip_remove(chip
);
1476 gpiochip_remove_pin_ranges(chip
);
1477 of_gpiochip_remove(chip
);
1478 gpiochip_free_valid_mask(chip
);
1480 * We accept no more calls into the driver from this point, so
1481 * NULL the driver data pointer
1485 spin_lock_irqsave(&gpio_lock
, flags
);
1486 for (i
= 0; i
< gdev
->ngpio
; i
++) {
1487 desc
= &gdev
->descs
[i
];
1488 if (test_bit(FLAG_REQUESTED
, &desc
->flags
))
1491 spin_unlock_irqrestore(&gpio_lock
, flags
);
1494 dev_crit(&gdev
->dev
,
1495 "REMOVING GPIOCHIP WITH GPIOS STILL REQUESTED\n");
1498 * The gpiochip side puts its use of the device to rest here:
1499 * if there are no userspace clients, the chardev and device will
1500 * be removed, else it will be dangling until the last user is
1503 cdev_device_del(&gdev
->chrdev
, &gdev
->dev
);
1504 put_device(&gdev
->dev
);
1506 EXPORT_SYMBOL_GPL(gpiochip_remove
);
1508 static void devm_gpio_chip_release(struct device
*dev
, void *res
)
1510 struct gpio_chip
*chip
= *(struct gpio_chip
**)res
;
1512 gpiochip_remove(chip
);
1516 * devm_gpiochip_add_data() - Resource manager gpiochip_add_data()
1517 * @dev: pointer to the device that gpio_chip belongs to.
1518 * @chip: the chip to register, with chip->base initialized
1519 * @data: driver-private data associated with this chip
1521 * Context: potentially before irqs will work
1523 * The gpio chip automatically be released when the device is unbound.
1526 * A negative errno if the chip can't be registered, such as because the
1527 * chip->base is invalid or already associated with a different chip.
1528 * Otherwise it returns zero as a success code.
1530 int devm_gpiochip_add_data(struct device
*dev
, struct gpio_chip
*chip
,
1533 struct gpio_chip
**ptr
;
1536 ptr
= devres_alloc(devm_gpio_chip_release
, sizeof(*ptr
),
1541 ret
= gpiochip_add_data(chip
, data
);
1548 devres_add(dev
, ptr
);
1552 EXPORT_SYMBOL_GPL(devm_gpiochip_add_data
);
1555 * gpiochip_find() - iterator for locating a specific gpio_chip
1556 * @data: data to pass to match function
1557 * @match: Callback function to check gpio_chip
1559 * Similar to bus_find_device. It returns a reference to a gpio_chip as
1560 * determined by a user supplied @match callback. The callback should return
1561 * 0 if the device doesn't match and non-zero if it does. If the callback is
1562 * non-zero, this function will return to the caller and not iterate over any
1565 struct gpio_chip
*gpiochip_find(void *data
,
1566 int (*match
)(struct gpio_chip
*chip
,
1569 struct gpio_device
*gdev
;
1570 struct gpio_chip
*chip
= NULL
;
1571 unsigned long flags
;
1573 spin_lock_irqsave(&gpio_lock
, flags
);
1574 list_for_each_entry(gdev
, &gpio_devices
, list
)
1575 if (gdev
->chip
&& match(gdev
->chip
, data
)) {
1580 spin_unlock_irqrestore(&gpio_lock
, flags
);
1584 EXPORT_SYMBOL_GPL(gpiochip_find
);
1586 static int gpiochip_match_name(struct gpio_chip
*chip
, void *data
)
1588 const char *name
= data
;
1590 return !strcmp(chip
->label
, name
);
1593 static struct gpio_chip
*find_chip_by_name(const char *name
)
1595 return gpiochip_find((void *)name
, gpiochip_match_name
);
1598 #ifdef CONFIG_GPIOLIB_IRQCHIP
1601 * The following is irqchip helper code for gpiochips.
1604 static int gpiochip_irqchip_init_valid_mask(struct gpio_chip
*gpiochip
)
1606 if (!gpiochip
->irq
.need_valid_mask
)
1609 gpiochip
->irq
.valid_mask
= gpiochip_allocate_mask(gpiochip
);
1610 if (!gpiochip
->irq
.valid_mask
)
1616 static void gpiochip_irqchip_free_valid_mask(struct gpio_chip
*gpiochip
)
1618 kfree(gpiochip
->irq
.valid_mask
);
1619 gpiochip
->irq
.valid_mask
= NULL
;
1622 bool gpiochip_irqchip_irq_valid(const struct gpio_chip
*gpiochip
,
1623 unsigned int offset
)
1625 if (!gpiochip_line_is_valid(gpiochip
, offset
))
1627 /* No mask means all valid */
1628 if (likely(!gpiochip
->irq
.valid_mask
))
1630 return test_bit(offset
, gpiochip
->irq
.valid_mask
);
1632 EXPORT_SYMBOL_GPL(gpiochip_irqchip_irq_valid
);
1635 * gpiochip_set_cascaded_irqchip() - connects a cascaded irqchip to a gpiochip
1636 * @gpiochip: the gpiochip to set the irqchip chain to
1637 * @parent_irq: the irq number corresponding to the parent IRQ for this
1639 * @parent_handler: the parent interrupt handler for the accumulated IRQ
1640 * coming out of the gpiochip. If the interrupt is nested rather than
1641 * cascaded, pass NULL in this handler argument
1643 static void gpiochip_set_cascaded_irqchip(struct gpio_chip
*gpiochip
,
1644 unsigned int parent_irq
,
1645 irq_flow_handler_t parent_handler
)
1647 if (!gpiochip
->irq
.domain
) {
1648 chip_err(gpiochip
, "called %s before setting up irqchip\n",
1653 if (parent_handler
) {
1654 if (gpiochip
->can_sleep
) {
1656 "you cannot have chained interrupts on a chip that may sleep\n");
1660 * The parent irqchip is already using the chip_data for this
1661 * irqchip, so our callbacks simply use the handler_data.
1663 irq_set_chained_handler_and_data(parent_irq
, parent_handler
,
1666 gpiochip
->irq
.parent_irq
= parent_irq
;
1667 gpiochip
->irq
.parents
= &gpiochip
->irq
.parent_irq
;
1668 gpiochip
->irq
.num_parents
= 1;
1673 * gpiochip_set_chained_irqchip() - connects a chained irqchip to a gpiochip
1674 * @gpiochip: the gpiochip to set the irqchip chain to
1675 * @irqchip: the irqchip to chain to the gpiochip
1676 * @parent_irq: the irq number corresponding to the parent IRQ for this
1678 * @parent_handler: the parent interrupt handler for the accumulated IRQ
1679 * coming out of the gpiochip.
1681 void gpiochip_set_chained_irqchip(struct gpio_chip
*gpiochip
,
1682 struct irq_chip
*irqchip
,
1683 unsigned int parent_irq
,
1684 irq_flow_handler_t parent_handler
)
1686 if (gpiochip
->irq
.threaded
) {
1687 chip_err(gpiochip
, "tried to chain a threaded gpiochip\n");
1691 gpiochip_set_cascaded_irqchip(gpiochip
, parent_irq
, parent_handler
);
1693 EXPORT_SYMBOL_GPL(gpiochip_set_chained_irqchip
);
1696 * gpiochip_set_nested_irqchip() - connects a nested irqchip to a gpiochip
1697 * @gpiochip: the gpiochip to set the irqchip nested handler to
1698 * @irqchip: the irqchip to nest to the gpiochip
1699 * @parent_irq: the irq number corresponding to the parent IRQ for this
1702 void gpiochip_set_nested_irqchip(struct gpio_chip
*gpiochip
,
1703 struct irq_chip
*irqchip
,
1704 unsigned int parent_irq
)
1706 gpiochip_set_cascaded_irqchip(gpiochip
, parent_irq
, NULL
);
1708 EXPORT_SYMBOL_GPL(gpiochip_set_nested_irqchip
);
1711 * gpiochip_irq_map() - maps an IRQ into a GPIO irqchip
1712 * @d: the irqdomain used by this irqchip
1713 * @irq: the global irq number used by this GPIO irqchip irq
1714 * @hwirq: the local IRQ/GPIO line offset on this gpiochip
1716 * This function will set up the mapping for a certain IRQ line on a
1717 * gpiochip by assigning the gpiochip as chip data, and using the irqchip
1718 * stored inside the gpiochip.
1720 int gpiochip_irq_map(struct irq_domain
*d
, unsigned int irq
,
1721 irq_hw_number_t hwirq
)
1723 struct gpio_chip
*chip
= d
->host_data
;
1726 if (!gpiochip_irqchip_irq_valid(chip
, hwirq
))
1729 irq_set_chip_data(irq
, chip
);
1731 * This lock class tells lockdep that GPIO irqs are in a different
1732 * category than their parents, so it won't report false recursion.
1734 irq_set_lockdep_class(irq
, chip
->irq
.lock_key
, chip
->irq
.request_key
);
1735 irq_set_chip_and_handler(irq
, chip
->irq
.chip
, chip
->irq
.handler
);
1736 /* Chips that use nested thread handlers have them marked */
1737 if (chip
->irq
.threaded
)
1738 irq_set_nested_thread(irq
, 1);
1739 irq_set_noprobe(irq
);
1741 if (chip
->irq
.num_parents
== 1)
1742 err
= irq_set_parent(irq
, chip
->irq
.parents
[0]);
1743 else if (chip
->irq
.map
)
1744 err
= irq_set_parent(irq
, chip
->irq
.map
[hwirq
]);
1750 * No set-up of the hardware will happen if IRQ_TYPE_NONE
1751 * is passed as default type.
1753 if (chip
->irq
.default_type
!= IRQ_TYPE_NONE
)
1754 irq_set_irq_type(irq
, chip
->irq
.default_type
);
1758 EXPORT_SYMBOL_GPL(gpiochip_irq_map
);
1760 void gpiochip_irq_unmap(struct irq_domain
*d
, unsigned int irq
)
1762 struct gpio_chip
*chip
= d
->host_data
;
1764 if (chip
->irq
.threaded
)
1765 irq_set_nested_thread(irq
, 0);
1766 irq_set_chip_and_handler(irq
, NULL
, NULL
);
1767 irq_set_chip_data(irq
, NULL
);
1769 EXPORT_SYMBOL_GPL(gpiochip_irq_unmap
);
1771 static const struct irq_domain_ops gpiochip_domain_ops
= {
1772 .map
= gpiochip_irq_map
,
1773 .unmap
= gpiochip_irq_unmap
,
1774 /* Virtually all GPIO irqchips are twocell:ed */
1775 .xlate
= irq_domain_xlate_twocell
,
1778 static int gpiochip_to_irq(struct gpio_chip
*chip
, unsigned offset
)
1780 if (!gpiochip_irqchip_irq_valid(chip
, offset
))
1783 return irq_create_mapping(chip
->irq
.domain
, offset
);
1786 static int gpiochip_irq_reqres(struct irq_data
*d
)
1788 struct gpio_chip
*chip
= irq_data_get_irq_chip_data(d
);
1790 return gpiochip_reqres_irq(chip
, d
->hwirq
);
1793 static void gpiochip_irq_relres(struct irq_data
*d
)
1795 struct gpio_chip
*chip
= irq_data_get_irq_chip_data(d
);
1797 gpiochip_relres_irq(chip
, d
->hwirq
);
1800 static void gpiochip_irq_enable(struct irq_data
*d
)
1802 struct gpio_chip
*chip
= irq_data_get_irq_chip_data(d
);
1804 gpiochip_enable_irq(chip
, d
->hwirq
);
1805 if (chip
->irq
.irq_enable
)
1806 chip
->irq
.irq_enable(d
);
1808 chip
->irq
.chip
->irq_unmask(d
);
1811 static void gpiochip_irq_disable(struct irq_data
*d
)
1813 struct gpio_chip
*chip
= irq_data_get_irq_chip_data(d
);
1815 if (chip
->irq
.irq_disable
)
1816 chip
->irq
.irq_disable(d
);
1818 chip
->irq
.chip
->irq_mask(d
);
1819 gpiochip_disable_irq(chip
, d
->hwirq
);
1822 static void gpiochip_set_irq_hooks(struct gpio_chip
*gpiochip
)
1824 struct irq_chip
*irqchip
= gpiochip
->irq
.chip
;
1826 if (!irqchip
->irq_request_resources
&&
1827 !irqchip
->irq_release_resources
) {
1828 irqchip
->irq_request_resources
= gpiochip_irq_reqres
;
1829 irqchip
->irq_release_resources
= gpiochip_irq_relres
;
1831 if (WARN_ON(gpiochip
->irq
.irq_enable
))
1833 /* Check if the irqchip already has this hook... */
1834 if (irqchip
->irq_enable
== gpiochip_irq_enable
) {
1836 * ...and if so, give a gentle warning that this is bad
1840 "detected irqchip that is shared with multiple gpiochips: please fix the driver.\n");
1843 gpiochip
->irq
.irq_enable
= irqchip
->irq_enable
;
1844 gpiochip
->irq
.irq_disable
= irqchip
->irq_disable
;
1845 irqchip
->irq_enable
= gpiochip_irq_enable
;
1846 irqchip
->irq_disable
= gpiochip_irq_disable
;
1850 * gpiochip_add_irqchip() - adds an IRQ chip to a GPIO chip
1851 * @gpiochip: the GPIO chip to add the IRQ chip to
1852 * @lock_key: lockdep class for IRQ lock
1853 * @request_key: lockdep class for IRQ request
1855 static int gpiochip_add_irqchip(struct gpio_chip
*gpiochip
,
1856 struct lock_class_key
*lock_key
,
1857 struct lock_class_key
*request_key
)
1859 struct irq_chip
*irqchip
= gpiochip
->irq
.chip
;
1860 const struct irq_domain_ops
*ops
;
1861 struct device_node
*np
;
1868 if (gpiochip
->irq
.parent_handler
&& gpiochip
->can_sleep
) {
1869 chip_err(gpiochip
, "you cannot have chained interrupts on a chip that may sleep\n");
1873 np
= gpiochip
->gpiodev
->dev
.of_node
;
1874 type
= gpiochip
->irq
.default_type
;
1877 * Specifying a default trigger is a terrible idea if DT or ACPI is
1878 * used to configure the interrupts, as you may end up with
1879 * conflicting triggers. Tell the user, and reset to NONE.
1881 if (WARN(np
&& type
!= IRQ_TYPE_NONE
,
1882 "%s: Ignoring %u default trigger\n", np
->full_name
, type
))
1883 type
= IRQ_TYPE_NONE
;
1885 if (has_acpi_companion(gpiochip
->parent
) && type
!= IRQ_TYPE_NONE
) {
1886 acpi_handle_warn(ACPI_HANDLE(gpiochip
->parent
),
1887 "Ignoring %u default trigger\n", type
);
1888 type
= IRQ_TYPE_NONE
;
1891 gpiochip
->to_irq
= gpiochip_to_irq
;
1892 gpiochip
->irq
.default_type
= type
;
1893 gpiochip
->irq
.lock_key
= lock_key
;
1894 gpiochip
->irq
.request_key
= request_key
;
1896 if (gpiochip
->irq
.domain_ops
)
1897 ops
= gpiochip
->irq
.domain_ops
;
1899 ops
= &gpiochip_domain_ops
;
1901 gpiochip
->irq
.domain
= irq_domain_add_simple(np
, gpiochip
->ngpio
,
1902 gpiochip
->irq
.first
,
1904 if (!gpiochip
->irq
.domain
)
1907 if (gpiochip
->irq
.parent_handler
) {
1908 void *data
= gpiochip
->irq
.parent_handler_data
?: gpiochip
;
1910 for (i
= 0; i
< gpiochip
->irq
.num_parents
; i
++) {
1912 * The parent IRQ chip is already using the chip_data
1913 * for this IRQ chip, so our callbacks simply use the
1916 irq_set_chained_handler_and_data(gpiochip
->irq
.parents
[i
],
1917 gpiochip
->irq
.parent_handler
,
1922 gpiochip_set_irq_hooks(gpiochip
);
1924 acpi_gpiochip_request_interrupts(gpiochip
);
1930 * gpiochip_irqchip_remove() - removes an irqchip added to a gpiochip
1931 * @gpiochip: the gpiochip to remove the irqchip from
1933 * This is called only from gpiochip_remove()
1935 static void gpiochip_irqchip_remove(struct gpio_chip
*gpiochip
)
1937 struct irq_chip
*irqchip
= gpiochip
->irq
.chip
;
1938 unsigned int offset
;
1940 acpi_gpiochip_free_interrupts(gpiochip
);
1942 if (irqchip
&& gpiochip
->irq
.parent_handler
) {
1943 struct gpio_irq_chip
*irq
= &gpiochip
->irq
;
1946 for (i
= 0; i
< irq
->num_parents
; i
++)
1947 irq_set_chained_handler_and_data(irq
->parents
[i
],
1951 /* Remove all IRQ mappings and delete the domain */
1952 if (gpiochip
->irq
.domain
) {
1955 for (offset
= 0; offset
< gpiochip
->ngpio
; offset
++) {
1956 if (!gpiochip_irqchip_irq_valid(gpiochip
, offset
))
1959 irq
= irq_find_mapping(gpiochip
->irq
.domain
, offset
);
1960 irq_dispose_mapping(irq
);
1963 irq_domain_remove(gpiochip
->irq
.domain
);
1967 if (irqchip
->irq_request_resources
== gpiochip_irq_reqres
) {
1968 irqchip
->irq_request_resources
= NULL
;
1969 irqchip
->irq_release_resources
= NULL
;
1971 if (irqchip
->irq_enable
== gpiochip_irq_enable
) {
1972 irqchip
->irq_enable
= gpiochip
->irq
.irq_enable
;
1973 irqchip
->irq_disable
= gpiochip
->irq
.irq_disable
;
1976 gpiochip
->irq
.irq_enable
= NULL
;
1977 gpiochip
->irq
.irq_disable
= NULL
;
1978 gpiochip
->irq
.chip
= NULL
;
1980 gpiochip_irqchip_free_valid_mask(gpiochip
);
1984 * gpiochip_irqchip_add_key() - adds an irqchip to a gpiochip
1985 * @gpiochip: the gpiochip to add the irqchip to
1986 * @irqchip: the irqchip to add to the gpiochip
1987 * @first_irq: if not dynamically assigned, the base (first) IRQ to
1988 * allocate gpiochip irqs from
1989 * @handler: the irq handler to use (often a predefined irq core function)
1990 * @type: the default type for IRQs on this irqchip, pass IRQ_TYPE_NONE
1991 * to have the core avoid setting up any default type in the hardware.
1992 * @threaded: whether this irqchip uses a nested thread handler
1993 * @lock_key: lockdep class for IRQ lock
1994 * @request_key: lockdep class for IRQ request
1996 * This function closely associates a certain irqchip with a certain
1997 * gpiochip, providing an irq domain to translate the local IRQs to
1998 * global irqs in the gpiolib core, and making sure that the gpiochip
1999 * is passed as chip data to all related functions. Driver callbacks
2000 * need to use gpiochip_get_data() to get their local state containers back
2001 * from the gpiochip passed as chip data. An irqdomain will be stored
2002 * in the gpiochip that shall be used by the driver to handle IRQ number
2003 * translation. The gpiochip will need to be initialized and registered
2004 * before calling this function.
2006 * This function will handle two cell:ed simple IRQs and assumes all
2007 * the pins on the gpiochip can generate a unique IRQ. Everything else
2008 * need to be open coded.
2010 int gpiochip_irqchip_add_key(struct gpio_chip
*gpiochip
,
2011 struct irq_chip
*irqchip
,
2012 unsigned int first_irq
,
2013 irq_flow_handler_t handler
,
2016 struct lock_class_key
*lock_key
,
2017 struct lock_class_key
*request_key
)
2019 struct device_node
*of_node
;
2021 if (!gpiochip
|| !irqchip
)
2024 if (!gpiochip
->parent
) {
2025 pr_err("missing gpiochip .dev parent pointer\n");
2028 gpiochip
->irq
.threaded
= threaded
;
2029 of_node
= gpiochip
->parent
->of_node
;
2030 #ifdef CONFIG_OF_GPIO
2032 * If the gpiochip has an assigned OF node this takes precedence
2033 * FIXME: get rid of this and use gpiochip->parent->of_node
2036 if (gpiochip
->of_node
)
2037 of_node
= gpiochip
->of_node
;
2040 * Specifying a default trigger is a terrible idea if DT or ACPI is
2041 * used to configure the interrupts, as you may end-up with
2042 * conflicting triggers. Tell the user, and reset to NONE.
2044 if (WARN(of_node
&& type
!= IRQ_TYPE_NONE
,
2045 "%pOF: Ignoring %d default trigger\n", of_node
, type
))
2046 type
= IRQ_TYPE_NONE
;
2047 if (has_acpi_companion(gpiochip
->parent
) && type
!= IRQ_TYPE_NONE
) {
2048 acpi_handle_warn(ACPI_HANDLE(gpiochip
->parent
),
2049 "Ignoring %d default trigger\n", type
);
2050 type
= IRQ_TYPE_NONE
;
2053 gpiochip
->irq
.chip
= irqchip
;
2054 gpiochip
->irq
.handler
= handler
;
2055 gpiochip
->irq
.default_type
= type
;
2056 gpiochip
->to_irq
= gpiochip_to_irq
;
2057 gpiochip
->irq
.lock_key
= lock_key
;
2058 gpiochip
->irq
.request_key
= request_key
;
2059 gpiochip
->irq
.domain
= irq_domain_add_simple(of_node
,
2060 gpiochip
->ngpio
, first_irq
,
2061 &gpiochip_domain_ops
, gpiochip
);
2062 if (!gpiochip
->irq
.domain
) {
2063 gpiochip
->irq
.chip
= NULL
;
2067 gpiochip_set_irq_hooks(gpiochip
);
2069 acpi_gpiochip_request_interrupts(gpiochip
);
2073 EXPORT_SYMBOL_GPL(gpiochip_irqchip_add_key
);
2075 #else /* CONFIG_GPIOLIB_IRQCHIP */
2077 static inline int gpiochip_add_irqchip(struct gpio_chip
*gpiochip
,
2078 struct lock_class_key
*lock_key
,
2079 struct lock_class_key
*request_key
)
2084 static void gpiochip_irqchip_remove(struct gpio_chip
*gpiochip
) {}
2085 static inline int gpiochip_irqchip_init_valid_mask(struct gpio_chip
*gpiochip
)
2089 static inline void gpiochip_irqchip_free_valid_mask(struct gpio_chip
*gpiochip
)
2092 #endif /* CONFIG_GPIOLIB_IRQCHIP */
2095 * gpiochip_generic_request() - request the gpio function for a pin
2096 * @chip: the gpiochip owning the GPIO
2097 * @offset: the offset of the GPIO to request for GPIO function
2099 int gpiochip_generic_request(struct gpio_chip
*chip
, unsigned offset
)
2101 return pinctrl_gpio_request(chip
->gpiodev
->base
+ offset
);
2103 EXPORT_SYMBOL_GPL(gpiochip_generic_request
);
2106 * gpiochip_generic_free() - free the gpio function from a pin
2107 * @chip: the gpiochip to request the gpio function for
2108 * @offset: the offset of the GPIO to free from GPIO function
2110 void gpiochip_generic_free(struct gpio_chip
*chip
, unsigned offset
)
2112 pinctrl_gpio_free(chip
->gpiodev
->base
+ offset
);
2114 EXPORT_SYMBOL_GPL(gpiochip_generic_free
);
2117 * gpiochip_generic_config() - apply configuration for a pin
2118 * @chip: the gpiochip owning the GPIO
2119 * @offset: the offset of the GPIO to apply the configuration
2120 * @config: the configuration to be applied
2122 int gpiochip_generic_config(struct gpio_chip
*chip
, unsigned offset
,
2123 unsigned long config
)
2125 return pinctrl_gpio_set_config(chip
->gpiodev
->base
+ offset
, config
);
2127 EXPORT_SYMBOL_GPL(gpiochip_generic_config
);
2129 #ifdef CONFIG_PINCTRL
2132 * gpiochip_add_pingroup_range() - add a range for GPIO <-> pin mapping
2133 * @chip: the gpiochip to add the range for
2134 * @pctldev: the pin controller to map to
2135 * @gpio_offset: the start offset in the current gpio_chip number space
2136 * @pin_group: name of the pin group inside the pin controller
2138 * Calling this function directly from a DeviceTree-supported
2139 * pinctrl driver is DEPRECATED. Please see Section 2.1 of
2140 * Documentation/devicetree/bindings/gpio/gpio.txt on how to
2141 * bind pinctrl and gpio drivers via the "gpio-ranges" property.
2143 int gpiochip_add_pingroup_range(struct gpio_chip
*chip
,
2144 struct pinctrl_dev
*pctldev
,
2145 unsigned int gpio_offset
, const char *pin_group
)
2147 struct gpio_pin_range
*pin_range
;
2148 struct gpio_device
*gdev
= chip
->gpiodev
;
2151 pin_range
= kzalloc(sizeof(*pin_range
), GFP_KERNEL
);
2153 chip_err(chip
, "failed to allocate pin ranges\n");
2157 /* Use local offset as range ID */
2158 pin_range
->range
.id
= gpio_offset
;
2159 pin_range
->range
.gc
= chip
;
2160 pin_range
->range
.name
= chip
->label
;
2161 pin_range
->range
.base
= gdev
->base
+ gpio_offset
;
2162 pin_range
->pctldev
= pctldev
;
2164 ret
= pinctrl_get_group_pins(pctldev
, pin_group
,
2165 &pin_range
->range
.pins
,
2166 &pin_range
->range
.npins
);
2172 pinctrl_add_gpio_range(pctldev
, &pin_range
->range
);
2174 chip_dbg(chip
, "created GPIO range %d->%d ==> %s PINGRP %s\n",
2175 gpio_offset
, gpio_offset
+ pin_range
->range
.npins
- 1,
2176 pinctrl_dev_get_devname(pctldev
), pin_group
);
2178 list_add_tail(&pin_range
->node
, &gdev
->pin_ranges
);
2182 EXPORT_SYMBOL_GPL(gpiochip_add_pingroup_range
);
2185 * gpiochip_add_pin_range() - add a range for GPIO <-> pin mapping
2186 * @chip: the gpiochip to add the range for
2187 * @pinctl_name: the dev_name() of the pin controller to map to
2188 * @gpio_offset: the start offset in the current gpio_chip number space
2189 * @pin_offset: the start offset in the pin controller number space
2190 * @npins: the number of pins from the offset of each pin space (GPIO and
2191 * pin controller) to accumulate in this range
2194 * 0 on success, or a negative error-code on failure.
2196 * Calling this function directly from a DeviceTree-supported
2197 * pinctrl driver is DEPRECATED. Please see Section 2.1 of
2198 * Documentation/devicetree/bindings/gpio/gpio.txt on how to
2199 * bind pinctrl and gpio drivers via the "gpio-ranges" property.
2201 int gpiochip_add_pin_range(struct gpio_chip
*chip
, const char *pinctl_name
,
2202 unsigned int gpio_offset
, unsigned int pin_offset
,
2205 struct gpio_pin_range
*pin_range
;
2206 struct gpio_device
*gdev
= chip
->gpiodev
;
2209 pin_range
= kzalloc(sizeof(*pin_range
), GFP_KERNEL
);
2211 chip_err(chip
, "failed to allocate pin ranges\n");
2215 /* Use local offset as range ID */
2216 pin_range
->range
.id
= gpio_offset
;
2217 pin_range
->range
.gc
= chip
;
2218 pin_range
->range
.name
= chip
->label
;
2219 pin_range
->range
.base
= gdev
->base
+ gpio_offset
;
2220 pin_range
->range
.pin_base
= pin_offset
;
2221 pin_range
->range
.npins
= npins
;
2222 pin_range
->pctldev
= pinctrl_find_and_add_gpio_range(pinctl_name
,
2224 if (IS_ERR(pin_range
->pctldev
)) {
2225 ret
= PTR_ERR(pin_range
->pctldev
);
2226 chip_err(chip
, "could not create pin range\n");
2230 chip_dbg(chip
, "created GPIO range %d->%d ==> %s PIN %d->%d\n",
2231 gpio_offset
, gpio_offset
+ npins
- 1,
2233 pin_offset
, pin_offset
+ npins
- 1);
2235 list_add_tail(&pin_range
->node
, &gdev
->pin_ranges
);
2239 EXPORT_SYMBOL_GPL(gpiochip_add_pin_range
);
2242 * gpiochip_remove_pin_ranges() - remove all the GPIO <-> pin mappings
2243 * @chip: the chip to remove all the mappings for
2245 void gpiochip_remove_pin_ranges(struct gpio_chip
*chip
)
2247 struct gpio_pin_range
*pin_range
, *tmp
;
2248 struct gpio_device
*gdev
= chip
->gpiodev
;
2250 list_for_each_entry_safe(pin_range
, tmp
, &gdev
->pin_ranges
, node
) {
2251 list_del(&pin_range
->node
);
2252 pinctrl_remove_gpio_range(pin_range
->pctldev
,
2257 EXPORT_SYMBOL_GPL(gpiochip_remove_pin_ranges
);
2259 #endif /* CONFIG_PINCTRL */
2261 /* These "optional" allocation calls help prevent drivers from stomping
2262 * on each other, and help provide better diagnostics in debugfs.
2263 * They're called even less than the "set direction" calls.
2265 static int gpiod_request_commit(struct gpio_desc
*desc
, const char *label
)
2267 struct gpio_chip
*chip
= desc
->gdev
->chip
;
2269 unsigned long flags
;
2273 label
= kstrdup_const(label
, GFP_KERNEL
);
2278 spin_lock_irqsave(&gpio_lock
, flags
);
2280 /* NOTE: gpio_request() can be called in early boot,
2281 * before IRQs are enabled, for non-sleeping (SOC) GPIOs.
2284 if (test_and_set_bit(FLAG_REQUESTED
, &desc
->flags
) == 0) {
2285 desc_set_label(desc
, label
? : "?");
2293 if (chip
->request
) {
2294 /* chip->request may sleep */
2295 spin_unlock_irqrestore(&gpio_lock
, flags
);
2296 offset
= gpio_chip_hwgpio(desc
);
2297 if (gpiochip_line_is_valid(chip
, offset
))
2298 status
= chip
->request(chip
, offset
);
2301 spin_lock_irqsave(&gpio_lock
, flags
);
2304 desc_set_label(desc
, NULL
);
2306 clear_bit(FLAG_REQUESTED
, &desc
->flags
);
2310 if (chip
->get_direction
) {
2311 /* chip->get_direction may sleep */
2312 spin_unlock_irqrestore(&gpio_lock
, flags
);
2313 gpiod_get_direction(desc
);
2314 spin_lock_irqsave(&gpio_lock
, flags
);
2317 spin_unlock_irqrestore(&gpio_lock
, flags
);
2322 * This descriptor validation needs to be inserted verbatim into each
2323 * function taking a descriptor, so we need to use a preprocessor
2324 * macro to avoid endless duplication. If the desc is NULL it is an
2325 * optional GPIO and calls should just bail out.
2327 static int validate_desc(const struct gpio_desc
*desc
, const char *func
)
2332 pr_warn("%s: invalid GPIO (errorpointer)\n", func
);
2333 return PTR_ERR(desc
);
2336 pr_warn("%s: invalid GPIO (no device)\n", func
);
2339 if (!desc
->gdev
->chip
) {
2340 dev_warn(&desc
->gdev
->dev
,
2341 "%s: backing chip is gone\n", func
);
2347 #define VALIDATE_DESC(desc) do { \
2348 int __valid = validate_desc(desc, __func__); \
2353 #define VALIDATE_DESC_VOID(desc) do { \
2354 int __valid = validate_desc(desc, __func__); \
2359 int gpiod_request(struct gpio_desc
*desc
, const char *label
)
2361 int status
= -EPROBE_DEFER
;
2362 struct gpio_device
*gdev
;
2364 VALIDATE_DESC(desc
);
2367 if (try_module_get(gdev
->owner
)) {
2368 status
= gpiod_request_commit(desc
, label
);
2370 module_put(gdev
->owner
);
2372 get_device(&gdev
->dev
);
2376 gpiod_dbg(desc
, "%s: status %d\n", __func__
, status
);
2381 static bool gpiod_free_commit(struct gpio_desc
*desc
)
2384 unsigned long flags
;
2385 struct gpio_chip
*chip
;
2389 gpiod_unexport(desc
);
2391 spin_lock_irqsave(&gpio_lock
, flags
);
2393 chip
= desc
->gdev
->chip
;
2394 if (chip
&& test_bit(FLAG_REQUESTED
, &desc
->flags
)) {
2396 spin_unlock_irqrestore(&gpio_lock
, flags
);
2397 might_sleep_if(chip
->can_sleep
);
2398 chip
->free(chip
, gpio_chip_hwgpio(desc
));
2399 spin_lock_irqsave(&gpio_lock
, flags
);
2401 kfree_const(desc
->label
);
2402 desc_set_label(desc
, NULL
);
2403 clear_bit(FLAG_ACTIVE_LOW
, &desc
->flags
);
2404 clear_bit(FLAG_REQUESTED
, &desc
->flags
);
2405 clear_bit(FLAG_OPEN_DRAIN
, &desc
->flags
);
2406 clear_bit(FLAG_OPEN_SOURCE
, &desc
->flags
);
2407 clear_bit(FLAG_IS_HOGGED
, &desc
->flags
);
2411 spin_unlock_irqrestore(&gpio_lock
, flags
);
2415 void gpiod_free(struct gpio_desc
*desc
)
2417 if (desc
&& desc
->gdev
&& gpiod_free_commit(desc
)) {
2418 module_put(desc
->gdev
->owner
);
2419 put_device(&desc
->gdev
->dev
);
2421 WARN_ON(extra_checks
);
2426 * gpiochip_is_requested - return string iff signal was requested
2427 * @chip: controller managing the signal
2428 * @offset: of signal within controller's 0..(ngpio - 1) range
2430 * Returns NULL if the GPIO is not currently requested, else a string.
2431 * The string returned is the label passed to gpio_request(); if none has been
2432 * passed it is a meaningless, non-NULL constant.
2434 * This function is for use by GPIO controller drivers. The label can
2435 * help with diagnostics, and knowing that the signal is used as a GPIO
2436 * can help avoid accidentally multiplexing it to another controller.
2438 const char *gpiochip_is_requested(struct gpio_chip
*chip
, unsigned offset
)
2440 struct gpio_desc
*desc
;
2442 if (offset
>= chip
->ngpio
)
2445 desc
= &chip
->gpiodev
->descs
[offset
];
2447 if (test_bit(FLAG_REQUESTED
, &desc
->flags
) == 0)
2451 EXPORT_SYMBOL_GPL(gpiochip_is_requested
);
2454 * gpiochip_request_own_desc - Allow GPIO chip to request its own descriptor
2456 * @hwnum: hardware number of the GPIO for which to request the descriptor
2457 * @label: label for the GPIO
2458 * @flags: flags for this GPIO or 0 if default
2460 * Function allows GPIO chip drivers to request and use their own GPIO
2461 * descriptors via gpiolib API. Difference to gpiod_request() is that this
2462 * function will not increase reference count of the GPIO chip module. This
2463 * allows the GPIO chip module to be unloaded as needed (we assume that the
2464 * GPIO chip driver handles freeing the GPIOs it has requested).
2467 * A pointer to the GPIO descriptor, or an ERR_PTR()-encoded negative error
2470 struct gpio_desc
*gpiochip_request_own_desc(struct gpio_chip
*chip
, u16 hwnum
,
2472 enum gpiod_flags flags
)
2474 struct gpio_desc
*desc
= gpiochip_get_desc(chip
, hwnum
);
2478 chip_err(chip
, "failed to get GPIO descriptor\n");
2482 err
= gpiod_request_commit(desc
, label
);
2484 return ERR_PTR(err
);
2486 err
= gpiod_configure_flags(desc
, label
, 0, flags
);
2488 chip_err(chip
, "setup of own GPIO %s failed\n", label
);
2489 gpiod_free_commit(desc
);
2490 return ERR_PTR(err
);
2495 EXPORT_SYMBOL_GPL(gpiochip_request_own_desc
);
2498 * gpiochip_free_own_desc - Free GPIO requested by the chip driver
2499 * @desc: GPIO descriptor to free
2501 * Function frees the given GPIO requested previously with
2502 * gpiochip_request_own_desc().
2504 void gpiochip_free_own_desc(struct gpio_desc
*desc
)
2507 gpiod_free_commit(desc
);
2509 EXPORT_SYMBOL_GPL(gpiochip_free_own_desc
);
2512 * Drivers MUST set GPIO direction before making get/set calls. In
2513 * some cases this is done in early boot, before IRQs are enabled.
2515 * As a rule these aren't called more than once (except for drivers
2516 * using the open-drain emulation idiom) so these are natural places
2517 * to accumulate extra debugging checks. Note that we can't (yet)
2518 * rely on gpio_request() having been called beforehand.
2522 * gpiod_direction_input - set the GPIO direction to input
2523 * @desc: GPIO to set to input
2525 * Set the direction of the passed GPIO to input, such as gpiod_get_value() can
2526 * be called safely on it.
2528 * Return 0 in case of success, else an error code.
2530 int gpiod_direction_input(struct gpio_desc
*desc
)
2532 struct gpio_chip
*chip
;
2535 VALIDATE_DESC(desc
);
2536 chip
= desc
->gdev
->chip
;
2539 * It is legal to have no .get() and .direction_input() specified if
2540 * the chip is output-only, but you can't specify .direction_input()
2541 * and not support the .get() operation, that doesn't make sense.
2543 if (!chip
->get
&& chip
->direction_input
) {
2545 "%s: missing get() but have direction_input()\n",
2551 * If we have a .direction_input() callback, things are simple,
2552 * just call it. Else we are some input-only chip so try to check the
2553 * direction (if .get_direction() is supported) else we silently
2554 * assume we are in input mode after this.
2556 if (chip
->direction_input
) {
2557 status
= chip
->direction_input(chip
, gpio_chip_hwgpio(desc
));
2558 } else if (chip
->get_direction
&&
2559 (chip
->get_direction(chip
, gpio_chip_hwgpio(desc
)) != 1)) {
2561 "%s: missing direction_input() operation and line is output\n",
2566 clear_bit(FLAG_IS_OUT
, &desc
->flags
);
2568 trace_gpio_direction(desc_to_gpio(desc
), 1, status
);
2572 EXPORT_SYMBOL_GPL(gpiod_direction_input
);
2574 static int gpio_set_drive_single_ended(struct gpio_chip
*gc
, unsigned offset
,
2575 enum pin_config_param mode
)
2577 unsigned long config
= { PIN_CONF_PACKED(mode
, 0) };
2579 return gc
->set_config
? gc
->set_config(gc
, offset
, config
) : -ENOTSUPP
;
2582 static int gpiod_direction_output_raw_commit(struct gpio_desc
*desc
, int value
)
2584 struct gpio_chip
*gc
= desc
->gdev
->chip
;
2589 * It's OK not to specify .direction_output() if the gpiochip is
2590 * output-only, but if there is then not even a .set() operation it
2591 * is pretty tricky to drive the output line.
2593 if (!gc
->set
&& !gc
->direction_output
) {
2595 "%s: missing set() and direction_output() operations\n",
2600 if (gc
->direction_output
) {
2601 ret
= gc
->direction_output(gc
, gpio_chip_hwgpio(desc
), val
);
2603 /* Check that we are in output mode if we can */
2604 if (gc
->get_direction
&&
2605 gc
->get_direction(gc
, gpio_chip_hwgpio(desc
))) {
2607 "%s: missing direction_output() operation\n",
2612 * If we can't actively set the direction, we are some
2613 * output-only chip, so just drive the output as desired.
2615 gc
->set(gc
, gpio_chip_hwgpio(desc
), val
);
2619 set_bit(FLAG_IS_OUT
, &desc
->flags
);
2620 trace_gpio_value(desc_to_gpio(desc
), 0, val
);
2621 trace_gpio_direction(desc_to_gpio(desc
), 0, ret
);
2626 * gpiod_direction_output_raw - set the GPIO direction to output
2627 * @desc: GPIO to set to output
2628 * @value: initial output value of the GPIO
2630 * Set the direction of the passed GPIO to output, such as gpiod_set_value() can
2631 * be called safely on it. The initial value of the output must be specified
2632 * as raw value on the physical line without regard for the ACTIVE_LOW status.
2634 * Return 0 in case of success, else an error code.
2636 int gpiod_direction_output_raw(struct gpio_desc
*desc
, int value
)
2638 VALIDATE_DESC(desc
);
2639 return gpiod_direction_output_raw_commit(desc
, value
);
2641 EXPORT_SYMBOL_GPL(gpiod_direction_output_raw
);
2644 * gpiod_direction_output - set the GPIO direction to output
2645 * @desc: GPIO to set to output
2646 * @value: initial output value of the GPIO
2648 * Set the direction of the passed GPIO to output, such as gpiod_set_value() can
2649 * be called safely on it. The initial value of the output must be specified
2650 * as the logical value of the GPIO, i.e. taking its ACTIVE_LOW status into
2653 * Return 0 in case of success, else an error code.
2655 int gpiod_direction_output(struct gpio_desc
*desc
, int value
)
2657 struct gpio_chip
*gc
;
2660 VALIDATE_DESC(desc
);
2661 if (test_bit(FLAG_ACTIVE_LOW
, &desc
->flags
))
2666 /* GPIOs used for enabled IRQs shall not be set as output */
2667 if (test_bit(FLAG_USED_AS_IRQ
, &desc
->flags
) &&
2668 test_bit(FLAG_IRQ_IS_ENABLED
, &desc
->flags
)) {
2670 "%s: tried to set a GPIO tied to an IRQ as output\n",
2675 gc
= desc
->gdev
->chip
;
2676 if (test_bit(FLAG_OPEN_DRAIN
, &desc
->flags
)) {
2677 /* First see if we can enable open drain in hardware */
2678 ret
= gpio_set_drive_single_ended(gc
, gpio_chip_hwgpio(desc
),
2679 PIN_CONFIG_DRIVE_OPEN_DRAIN
);
2681 goto set_output_value
;
2682 /* Emulate open drain by not actively driving the line high */
2684 return gpiod_direction_input(desc
);
2686 else if (test_bit(FLAG_OPEN_SOURCE
, &desc
->flags
)) {
2687 ret
= gpio_set_drive_single_ended(gc
, gpio_chip_hwgpio(desc
),
2688 PIN_CONFIG_DRIVE_OPEN_SOURCE
);
2690 goto set_output_value
;
2691 /* Emulate open source by not actively driving the line low */
2693 return gpiod_direction_input(desc
);
2695 gpio_set_drive_single_ended(gc
, gpio_chip_hwgpio(desc
),
2696 PIN_CONFIG_DRIVE_PUSH_PULL
);
2700 return gpiod_direction_output_raw_commit(desc
, value
);
2702 EXPORT_SYMBOL_GPL(gpiod_direction_output
);
2705 * gpiod_set_debounce - sets @debounce time for a GPIO
2706 * @desc: descriptor of the GPIO for which to set debounce time
2707 * @debounce: debounce time in microseconds
2710 * 0 on success, %-ENOTSUPP if the controller doesn't support setting the
2713 int gpiod_set_debounce(struct gpio_desc
*desc
, unsigned debounce
)
2715 struct gpio_chip
*chip
;
2716 unsigned long config
;
2718 VALIDATE_DESC(desc
);
2719 chip
= desc
->gdev
->chip
;
2720 if (!chip
->set
|| !chip
->set_config
) {
2722 "%s: missing set() or set_config() operations\n",
2727 config
= pinconf_to_config_packed(PIN_CONFIG_INPUT_DEBOUNCE
, debounce
);
2728 return chip
->set_config(chip
, gpio_chip_hwgpio(desc
), config
);
2730 EXPORT_SYMBOL_GPL(gpiod_set_debounce
);
2733 * gpiod_set_transitory - Lose or retain GPIO state on suspend or reset
2734 * @desc: descriptor of the GPIO for which to configure persistence
2735 * @transitory: True to lose state on suspend or reset, false for persistence
2738 * 0 on success, otherwise a negative error code.
2740 int gpiod_set_transitory(struct gpio_desc
*desc
, bool transitory
)
2742 struct gpio_chip
*chip
;
2743 unsigned long packed
;
2747 VALIDATE_DESC(desc
);
2749 * Handle FLAG_TRANSITORY first, enabling queries to gpiolib for
2750 * persistence state.
2753 set_bit(FLAG_TRANSITORY
, &desc
->flags
);
2755 clear_bit(FLAG_TRANSITORY
, &desc
->flags
);
2757 /* If the driver supports it, set the persistence state now */
2758 chip
= desc
->gdev
->chip
;
2759 if (!chip
->set_config
)
2762 packed
= pinconf_to_config_packed(PIN_CONFIG_PERSIST_STATE
,
2764 gpio
= gpio_chip_hwgpio(desc
);
2765 rc
= chip
->set_config(chip
, gpio
, packed
);
2766 if (rc
== -ENOTSUPP
) {
2767 dev_dbg(&desc
->gdev
->dev
, "Persistence not supported for GPIO %d\n",
2774 EXPORT_SYMBOL_GPL(gpiod_set_transitory
);
2777 * gpiod_is_active_low - test whether a GPIO is active-low or not
2778 * @desc: the gpio descriptor to test
2780 * Returns 1 if the GPIO is active-low, 0 otherwise.
2782 int gpiod_is_active_low(const struct gpio_desc
*desc
)
2784 VALIDATE_DESC(desc
);
2785 return test_bit(FLAG_ACTIVE_LOW
, &desc
->flags
);
2787 EXPORT_SYMBOL_GPL(gpiod_is_active_low
);
2789 /* I/O calls are only valid after configuration completed; the relevant
2790 * "is this a valid GPIO" error checks should already have been done.
2792 * "Get" operations are often inlinable as reading a pin value register,
2793 * and masking the relevant bit in that register.
2795 * When "set" operations are inlinable, they involve writing that mask to
2796 * one register to set a low value, or a different register to set it high.
2797 * Otherwise locking is needed, so there may be little value to inlining.
2799 *------------------------------------------------------------------------
2801 * IMPORTANT!!! The hot paths -- get/set value -- assume that callers
2802 * have requested the GPIO. That can include implicit requesting by
2803 * a direction setting call. Marking a gpio as requested locks its chip
2804 * in memory, guaranteeing that these table lookups need no more locking
2805 * and that gpiochip_remove() will fail.
2807 * REVISIT when debugging, consider adding some instrumentation to ensure
2808 * that the GPIO was actually requested.
2811 static int gpiod_get_raw_value_commit(const struct gpio_desc
*desc
)
2813 struct gpio_chip
*chip
;
2817 chip
= desc
->gdev
->chip
;
2818 offset
= gpio_chip_hwgpio(desc
);
2819 value
= chip
->get
? chip
->get(chip
, offset
) : -EIO
;
2820 value
= value
< 0 ? value
: !!value
;
2821 trace_gpio_value(desc_to_gpio(desc
), 1, value
);
2825 static int gpio_chip_get_multiple(struct gpio_chip
*chip
,
2826 unsigned long *mask
, unsigned long *bits
)
2828 if (chip
->get_multiple
) {
2829 return chip
->get_multiple(chip
, mask
, bits
);
2830 } else if (chip
->get
) {
2833 for_each_set_bit(i
, mask
, chip
->ngpio
) {
2834 value
= chip
->get(chip
, i
);
2837 __assign_bit(i
, bits
, value
);
2844 int gpiod_get_array_value_complex(bool raw
, bool can_sleep
,
2845 unsigned int array_size
,
2846 struct gpio_desc
**desc_array
,
2847 struct gpio_array
*array_info
,
2848 unsigned long *value_bitmap
)
2853 * Validate array_info against desc_array and its size.
2854 * It should immediately follow desc_array if both
2855 * have been obtained from the same gpiod_get_array() call.
2857 if (array_info
&& array_info
->desc
== desc_array
&&
2858 array_size
<= array_info
->size
&&
2859 (void *)array_info
== desc_array
+ array_info
->size
) {
2861 WARN_ON(array_info
->chip
->can_sleep
);
2863 err
= gpio_chip_get_multiple(array_info
->chip
,
2864 array_info
->get_mask
,
2869 if (!raw
&& !bitmap_empty(array_info
->invert_mask
, array_size
))
2870 bitmap_xor(value_bitmap
, value_bitmap
,
2871 array_info
->invert_mask
, array_size
);
2873 if (bitmap_full(array_info
->get_mask
, array_size
))
2876 i
= find_first_zero_bit(array_info
->get_mask
, array_size
);
2881 while (i
< array_size
) {
2882 struct gpio_chip
*chip
= desc_array
[i
]->gdev
->chip
;
2883 unsigned long fastpath
[2 * BITS_TO_LONGS(FASTPATH_NGPIO
)];
2884 unsigned long *mask
, *bits
;
2887 if (likely(chip
->ngpio
<= FASTPATH_NGPIO
)) {
2890 mask
= kmalloc_array(2 * BITS_TO_LONGS(chip
->ngpio
),
2892 can_sleep
? GFP_KERNEL
: GFP_ATOMIC
);
2897 bits
= mask
+ BITS_TO_LONGS(chip
->ngpio
);
2898 bitmap_zero(mask
, chip
->ngpio
);
2901 WARN_ON(chip
->can_sleep
);
2903 /* collect all inputs belonging to the same chip */
2906 const struct gpio_desc
*desc
= desc_array
[i
];
2907 int hwgpio
= gpio_chip_hwgpio(desc
);
2909 __set_bit(hwgpio
, mask
);
2913 i
= find_next_zero_bit(array_info
->get_mask
,
2915 } while ((i
< array_size
) &&
2916 (desc_array
[i
]->gdev
->chip
== chip
));
2918 ret
= gpio_chip_get_multiple(chip
, mask
, bits
);
2920 if (mask
!= fastpath
)
2925 for (j
= first
; j
< i
; ) {
2926 const struct gpio_desc
*desc
= desc_array
[j
];
2927 int hwgpio
= gpio_chip_hwgpio(desc
);
2928 int value
= test_bit(hwgpio
, bits
);
2930 if (!raw
&& test_bit(FLAG_ACTIVE_LOW
, &desc
->flags
))
2932 __assign_bit(j
, value_bitmap
, value
);
2933 trace_gpio_value(desc_to_gpio(desc
), 1, value
);
2937 j
= find_next_zero_bit(array_info
->get_mask
, i
,
2941 if (mask
!= fastpath
)
2948 * gpiod_get_raw_value() - return a gpio's raw value
2949 * @desc: gpio whose value will be returned
2951 * Return the GPIO's raw value, i.e. the value of the physical line disregarding
2952 * its ACTIVE_LOW status, or negative errno on failure.
2954 * This function should be called from contexts where we cannot sleep, and will
2955 * complain if the GPIO chip functions potentially sleep.
2957 int gpiod_get_raw_value(const struct gpio_desc
*desc
)
2959 VALIDATE_DESC(desc
);
2960 /* Should be using gpio_get_value_cansleep() */
2961 WARN_ON(desc
->gdev
->chip
->can_sleep
);
2962 return gpiod_get_raw_value_commit(desc
);
2964 EXPORT_SYMBOL_GPL(gpiod_get_raw_value
);
2967 * gpiod_get_value() - return a gpio's value
2968 * @desc: gpio whose value will be returned
2970 * Return the GPIO's logical value, i.e. taking the ACTIVE_LOW status into
2971 * account, or negative errno on failure.
2973 * This function should be called from contexts where we cannot sleep, and will
2974 * complain if the GPIO chip functions potentially sleep.
2976 int gpiod_get_value(const struct gpio_desc
*desc
)
2980 VALIDATE_DESC(desc
);
2981 /* Should be using gpio_get_value_cansleep() */
2982 WARN_ON(desc
->gdev
->chip
->can_sleep
);
2984 value
= gpiod_get_raw_value_commit(desc
);
2988 if (test_bit(FLAG_ACTIVE_LOW
, &desc
->flags
))
2993 EXPORT_SYMBOL_GPL(gpiod_get_value
);
2996 * gpiod_get_raw_array_value() - read raw values from an array of GPIOs
2997 * @array_size: number of elements in the descriptor array / value bitmap
2998 * @desc_array: array of GPIO descriptors whose values will be read
2999 * @array_info: information on applicability of fast bitmap processing path
3000 * @value_bitmap: bitmap to store the read values
3002 * Read the raw values of the GPIOs, i.e. the values of the physical lines
3003 * without regard for their ACTIVE_LOW status. Return 0 in case of success,
3004 * else an error code.
3006 * This function should be called from contexts where we cannot sleep,
3007 * and it will complain if the GPIO chip functions potentially sleep.
3009 int gpiod_get_raw_array_value(unsigned int array_size
,
3010 struct gpio_desc
**desc_array
,
3011 struct gpio_array
*array_info
,
3012 unsigned long *value_bitmap
)
3016 return gpiod_get_array_value_complex(true, false, array_size
,
3017 desc_array
, array_info
,
3020 EXPORT_SYMBOL_GPL(gpiod_get_raw_array_value
);
3023 * gpiod_get_array_value() - read values from an array of GPIOs
3024 * @array_size: number of elements in the descriptor array / value bitmap
3025 * @desc_array: array of GPIO descriptors whose values will be read
3026 * @array_info: information on applicability of fast bitmap processing path
3027 * @value_bitmap: bitmap to store the read values
3029 * Read the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status
3030 * into account. Return 0 in case of success, else an error code.
3032 * This function should be called from contexts where we cannot sleep,
3033 * and it will complain if the GPIO chip functions potentially sleep.
3035 int gpiod_get_array_value(unsigned int array_size
,
3036 struct gpio_desc
**desc_array
,
3037 struct gpio_array
*array_info
,
3038 unsigned long *value_bitmap
)
3042 return gpiod_get_array_value_complex(false, false, array_size
,
3043 desc_array
, array_info
,
3046 EXPORT_SYMBOL_GPL(gpiod_get_array_value
);
3049 * gpio_set_open_drain_value_commit() - Set the open drain gpio's value.
3050 * @desc: gpio descriptor whose state need to be set.
3051 * @value: Non-zero for setting it HIGH otherwise it will set to LOW.
3053 static void gpio_set_open_drain_value_commit(struct gpio_desc
*desc
, bool value
)
3056 struct gpio_chip
*chip
= desc
->gdev
->chip
;
3057 int offset
= gpio_chip_hwgpio(desc
);
3060 err
= chip
->direction_input(chip
, offset
);
3062 clear_bit(FLAG_IS_OUT
, &desc
->flags
);
3064 err
= chip
->direction_output(chip
, offset
, 0);
3066 set_bit(FLAG_IS_OUT
, &desc
->flags
);
3068 trace_gpio_direction(desc_to_gpio(desc
), value
, err
);
3071 "%s: Error in set_value for open drain err %d\n",
3076 * _gpio_set_open_source_value() - Set the open source gpio's value.
3077 * @desc: gpio descriptor whose state need to be set.
3078 * @value: Non-zero for setting it HIGH otherwise it will set to LOW.
3080 static void gpio_set_open_source_value_commit(struct gpio_desc
*desc
, bool value
)
3083 struct gpio_chip
*chip
= desc
->gdev
->chip
;
3084 int offset
= gpio_chip_hwgpio(desc
);
3087 err
= chip
->direction_output(chip
, offset
, 1);
3089 set_bit(FLAG_IS_OUT
, &desc
->flags
);
3091 err
= chip
->direction_input(chip
, offset
);
3093 clear_bit(FLAG_IS_OUT
, &desc
->flags
);
3095 trace_gpio_direction(desc_to_gpio(desc
), !value
, err
);
3098 "%s: Error in set_value for open source err %d\n",
3102 static void gpiod_set_raw_value_commit(struct gpio_desc
*desc
, bool value
)
3104 struct gpio_chip
*chip
;
3106 chip
= desc
->gdev
->chip
;
3107 trace_gpio_value(desc_to_gpio(desc
), 0, value
);
3108 chip
->set(chip
, gpio_chip_hwgpio(desc
), value
);
3112 * set multiple outputs on the same chip;
3113 * use the chip's set_multiple function if available;
3114 * otherwise set the outputs sequentially;
3115 * @mask: bit mask array; one bit per output; BITS_PER_LONG bits per word
3116 * defines which outputs are to be changed
3117 * @bits: bit value array; one bit per output; BITS_PER_LONG bits per word
3118 * defines the values the outputs specified by mask are to be set to
3120 static void gpio_chip_set_multiple(struct gpio_chip
*chip
,
3121 unsigned long *mask
, unsigned long *bits
)
3123 if (chip
->set_multiple
) {
3124 chip
->set_multiple(chip
, mask
, bits
);
3128 /* set outputs if the corresponding mask bit is set */
3129 for_each_set_bit(i
, mask
, chip
->ngpio
)
3130 chip
->set(chip
, i
, test_bit(i
, bits
));
3134 int gpiod_set_array_value_complex(bool raw
, bool can_sleep
,
3135 unsigned int array_size
,
3136 struct gpio_desc
**desc_array
,
3137 struct gpio_array
*array_info
,
3138 unsigned long *value_bitmap
)
3143 * Validate array_info against desc_array and its size.
3144 * It should immediately follow desc_array if both
3145 * have been obtained from the same gpiod_get_array() call.
3147 if (array_info
&& array_info
->desc
== desc_array
&&
3148 array_size
<= array_info
->size
&&
3149 (void *)array_info
== desc_array
+ array_info
->size
) {
3151 WARN_ON(array_info
->chip
->can_sleep
);
3153 if (!raw
&& !bitmap_empty(array_info
->invert_mask
, array_size
))
3154 bitmap_xor(value_bitmap
, value_bitmap
,
3155 array_info
->invert_mask
, array_size
);
3157 gpio_chip_set_multiple(array_info
->chip
, array_info
->set_mask
,
3160 if (bitmap_full(array_info
->set_mask
, array_size
))
3163 i
= find_first_zero_bit(array_info
->set_mask
, array_size
);
3168 while (i
< array_size
) {
3169 struct gpio_chip
*chip
= desc_array
[i
]->gdev
->chip
;
3170 unsigned long fastpath
[2 * BITS_TO_LONGS(FASTPATH_NGPIO
)];
3171 unsigned long *mask
, *bits
;
3174 if (likely(chip
->ngpio
<= FASTPATH_NGPIO
)) {
3177 mask
= kmalloc_array(2 * BITS_TO_LONGS(chip
->ngpio
),
3179 can_sleep
? GFP_KERNEL
: GFP_ATOMIC
);
3184 bits
= mask
+ BITS_TO_LONGS(chip
->ngpio
);
3185 bitmap_zero(mask
, chip
->ngpio
);
3188 WARN_ON(chip
->can_sleep
);
3191 struct gpio_desc
*desc
= desc_array
[i
];
3192 int hwgpio
= gpio_chip_hwgpio(desc
);
3193 int value
= test_bit(i
, value_bitmap
);
3196 * Pins applicable for fast input but not for
3197 * fast output processing may have been already
3198 * inverted inside the fast path, skip them.
3200 if (!raw
&& !(array_info
&&
3201 test_bit(i
, array_info
->invert_mask
)) &&
3202 test_bit(FLAG_ACTIVE_LOW
, &desc
->flags
))
3204 trace_gpio_value(desc_to_gpio(desc
), 0, value
);
3206 * collect all normal outputs belonging to the same chip
3207 * open drain and open source outputs are set individually
3209 if (test_bit(FLAG_OPEN_DRAIN
, &desc
->flags
) && !raw
) {
3210 gpio_set_open_drain_value_commit(desc
, value
);
3211 } else if (test_bit(FLAG_OPEN_SOURCE
, &desc
->flags
) && !raw
) {
3212 gpio_set_open_source_value_commit(desc
, value
);
3214 __set_bit(hwgpio
, mask
);
3216 __set_bit(hwgpio
, bits
);
3218 __clear_bit(hwgpio
, bits
);
3224 i
= find_next_zero_bit(array_info
->set_mask
,
3226 } while ((i
< array_size
) &&
3227 (desc_array
[i
]->gdev
->chip
== chip
));
3228 /* push collected bits to outputs */
3230 gpio_chip_set_multiple(chip
, mask
, bits
);
3232 if (mask
!= fastpath
)
3239 * gpiod_set_raw_value() - assign a gpio's raw value
3240 * @desc: gpio whose value will be assigned
3241 * @value: value to assign
3243 * Set the raw value of the GPIO, i.e. the value of its physical line without
3244 * regard for its ACTIVE_LOW status.
3246 * This function should be called from contexts where we cannot sleep, and will
3247 * complain if the GPIO chip functions potentially sleep.
3249 void gpiod_set_raw_value(struct gpio_desc
*desc
, int value
)
3251 VALIDATE_DESC_VOID(desc
);
3252 /* Should be using gpiod_set_value_cansleep() */
3253 WARN_ON(desc
->gdev
->chip
->can_sleep
);
3254 gpiod_set_raw_value_commit(desc
, value
);
3256 EXPORT_SYMBOL_GPL(gpiod_set_raw_value
);
3259 * gpiod_set_value_nocheck() - set a GPIO line value without checking
3260 * @desc: the descriptor to set the value on
3261 * @value: value to set
3263 * This sets the value of a GPIO line backing a descriptor, applying
3264 * different semantic quirks like active low and open drain/source
3267 static void gpiod_set_value_nocheck(struct gpio_desc
*desc
, int value
)
3269 if (test_bit(FLAG_ACTIVE_LOW
, &desc
->flags
))
3271 if (test_bit(FLAG_OPEN_DRAIN
, &desc
->flags
))
3272 gpio_set_open_drain_value_commit(desc
, value
);
3273 else if (test_bit(FLAG_OPEN_SOURCE
, &desc
->flags
))
3274 gpio_set_open_source_value_commit(desc
, value
);
3276 gpiod_set_raw_value_commit(desc
, value
);
3280 * gpiod_set_value() - assign a gpio's value
3281 * @desc: gpio whose value will be assigned
3282 * @value: value to assign
3284 * Set the logical value of the GPIO, i.e. taking its ACTIVE_LOW,
3285 * OPEN_DRAIN and OPEN_SOURCE flags into account.
3287 * This function should be called from contexts where we cannot sleep, and will
3288 * complain if the GPIO chip functions potentially sleep.
3290 void gpiod_set_value(struct gpio_desc
*desc
, int value
)
3292 VALIDATE_DESC_VOID(desc
);
3293 WARN_ON(desc
->gdev
->chip
->can_sleep
);
3294 gpiod_set_value_nocheck(desc
, value
);
3296 EXPORT_SYMBOL_GPL(gpiod_set_value
);
3299 * gpiod_set_raw_array_value() - assign values to an array of GPIOs
3300 * @array_size: number of elements in the descriptor array / value bitmap
3301 * @desc_array: array of GPIO descriptors whose values will be assigned
3302 * @array_info: information on applicability of fast bitmap processing path
3303 * @value_bitmap: bitmap of values to assign
3305 * Set the raw values of the GPIOs, i.e. the values of the physical lines
3306 * without regard for their ACTIVE_LOW status.
3308 * This function should be called from contexts where we cannot sleep, and will
3309 * complain if the GPIO chip functions potentially sleep.
3311 int gpiod_set_raw_array_value(unsigned int array_size
,
3312 struct gpio_desc
**desc_array
,
3313 struct gpio_array
*array_info
,
3314 unsigned long *value_bitmap
)
3318 return gpiod_set_array_value_complex(true, false, array_size
,
3319 desc_array
, array_info
, value_bitmap
);
3321 EXPORT_SYMBOL_GPL(gpiod_set_raw_array_value
);
3324 * gpiod_set_array_value() - assign values to an array of GPIOs
3325 * @array_size: number of elements in the descriptor array / value bitmap
3326 * @desc_array: array of GPIO descriptors whose values will be assigned
3327 * @array_info: information on applicability of fast bitmap processing path
3328 * @value_bitmap: bitmap of values to assign
3330 * Set the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status
3333 * This function should be called from contexts where we cannot sleep, and will
3334 * complain if the GPIO chip functions potentially sleep.
3336 int gpiod_set_array_value(unsigned int array_size
,
3337 struct gpio_desc
**desc_array
,
3338 struct gpio_array
*array_info
,
3339 unsigned long *value_bitmap
)
3343 return gpiod_set_array_value_complex(false, false, array_size
,
3344 desc_array
, array_info
,
3347 EXPORT_SYMBOL_GPL(gpiod_set_array_value
);
3350 * gpiod_cansleep() - report whether gpio value access may sleep
3351 * @desc: gpio to check
3354 int gpiod_cansleep(const struct gpio_desc
*desc
)
3356 VALIDATE_DESC(desc
);
3357 return desc
->gdev
->chip
->can_sleep
;
3359 EXPORT_SYMBOL_GPL(gpiod_cansleep
);
3362 * gpiod_set_consumer_name() - set the consumer name for the descriptor
3363 * @desc: gpio to set the consumer name on
3364 * @name: the new consumer name
3366 int gpiod_set_consumer_name(struct gpio_desc
*desc
, const char *name
)
3368 VALIDATE_DESC(desc
);
3370 name
= kstrdup_const(name
, GFP_KERNEL
);
3375 kfree_const(desc
->label
);
3376 desc_set_label(desc
, name
);
3380 EXPORT_SYMBOL_GPL(gpiod_set_consumer_name
);
3383 * gpiod_to_irq() - return the IRQ corresponding to a GPIO
3384 * @desc: gpio whose IRQ will be returned (already requested)
3386 * Return the IRQ corresponding to the passed GPIO, or an error code in case of
3389 int gpiod_to_irq(const struct gpio_desc
*desc
)
3391 struct gpio_chip
*chip
;
3395 * Cannot VALIDATE_DESC() here as gpiod_to_irq() consumer semantics
3396 * requires this function to not return zero on an invalid descriptor
3397 * but rather a negative error number.
3399 if (!desc
|| IS_ERR(desc
) || !desc
->gdev
|| !desc
->gdev
->chip
)
3402 chip
= desc
->gdev
->chip
;
3403 offset
= gpio_chip_hwgpio(desc
);
3405 int retirq
= chip
->to_irq(chip
, offset
);
3407 /* Zero means NO_IRQ */
3415 EXPORT_SYMBOL_GPL(gpiod_to_irq
);
3418 * gpiochip_lock_as_irq() - lock a GPIO to be used as IRQ
3419 * @chip: the chip the GPIO to lock belongs to
3420 * @offset: the offset of the GPIO to lock as IRQ
3422 * This is used directly by GPIO drivers that want to lock down
3423 * a certain GPIO line to be used for IRQs.
3425 int gpiochip_lock_as_irq(struct gpio_chip
*chip
, unsigned int offset
)
3427 struct gpio_desc
*desc
;
3429 desc
= gpiochip_get_desc(chip
, offset
);
3431 return PTR_ERR(desc
);
3434 * If it's fast: flush the direction setting if something changed
3437 if (!chip
->can_sleep
&& chip
->get_direction
) {
3438 int dir
= gpiod_get_direction(desc
);
3441 chip_err(chip
, "%s: cannot get GPIO direction\n",
3447 if (test_bit(FLAG_IS_OUT
, &desc
->flags
)) {
3449 "%s: tried to flag a GPIO set as output for IRQ\n",
3454 set_bit(FLAG_USED_AS_IRQ
, &desc
->flags
);
3455 set_bit(FLAG_IRQ_IS_ENABLED
, &desc
->flags
);
3458 * If the consumer has not set up a label (such as when the
3459 * IRQ is referenced from .to_irq()) we set up a label here
3460 * so it is clear this is used as an interrupt.
3463 desc_set_label(desc
, "interrupt");
3467 EXPORT_SYMBOL_GPL(gpiochip_lock_as_irq
);
3470 * gpiochip_unlock_as_irq() - unlock a GPIO used as IRQ
3471 * @chip: the chip the GPIO to lock belongs to
3472 * @offset: the offset of the GPIO to lock as IRQ
3474 * This is used directly by GPIO drivers that want to indicate
3475 * that a certain GPIO is no longer used exclusively for IRQ.
3477 void gpiochip_unlock_as_irq(struct gpio_chip
*chip
, unsigned int offset
)
3479 struct gpio_desc
*desc
;
3481 desc
= gpiochip_get_desc(chip
, offset
);
3485 clear_bit(FLAG_USED_AS_IRQ
, &desc
->flags
);
3486 clear_bit(FLAG_IRQ_IS_ENABLED
, &desc
->flags
);
3488 /* If we only had this marking, erase it */
3489 if (desc
->label
&& !strcmp(desc
->label
, "interrupt"))
3490 desc_set_label(desc
, NULL
);
3492 EXPORT_SYMBOL_GPL(gpiochip_unlock_as_irq
);
3494 void gpiochip_disable_irq(struct gpio_chip
*chip
, unsigned int offset
)
3496 struct gpio_desc
*desc
= gpiochip_get_desc(chip
, offset
);
3498 if (!IS_ERR(desc
) &&
3499 !WARN_ON(!test_bit(FLAG_USED_AS_IRQ
, &desc
->flags
)))
3500 clear_bit(FLAG_IRQ_IS_ENABLED
, &desc
->flags
);
3502 EXPORT_SYMBOL_GPL(gpiochip_disable_irq
);
3504 void gpiochip_enable_irq(struct gpio_chip
*chip
, unsigned int offset
)
3506 struct gpio_desc
*desc
= gpiochip_get_desc(chip
, offset
);
3508 if (!IS_ERR(desc
) &&
3509 !WARN_ON(!test_bit(FLAG_USED_AS_IRQ
, &desc
->flags
))) {
3510 WARN_ON(test_bit(FLAG_IS_OUT
, &desc
->flags
));
3511 set_bit(FLAG_IRQ_IS_ENABLED
, &desc
->flags
);
3514 EXPORT_SYMBOL_GPL(gpiochip_enable_irq
);
3516 bool gpiochip_line_is_irq(struct gpio_chip
*chip
, unsigned int offset
)
3518 if (offset
>= chip
->ngpio
)
3521 return test_bit(FLAG_USED_AS_IRQ
, &chip
->gpiodev
->descs
[offset
].flags
);
3523 EXPORT_SYMBOL_GPL(gpiochip_line_is_irq
);
3525 int gpiochip_reqres_irq(struct gpio_chip
*chip
, unsigned int offset
)
3529 if (!try_module_get(chip
->gpiodev
->owner
))
3532 ret
= gpiochip_lock_as_irq(chip
, offset
);
3534 chip_err(chip
, "unable to lock HW IRQ %u for IRQ\n", offset
);
3535 module_put(chip
->gpiodev
->owner
);
3540 EXPORT_SYMBOL_GPL(gpiochip_reqres_irq
);
3542 void gpiochip_relres_irq(struct gpio_chip
*chip
, unsigned int offset
)
3544 gpiochip_unlock_as_irq(chip
, offset
);
3545 module_put(chip
->gpiodev
->owner
);
3547 EXPORT_SYMBOL_GPL(gpiochip_relres_irq
);
3549 bool gpiochip_line_is_open_drain(struct gpio_chip
*chip
, unsigned int offset
)
3551 if (offset
>= chip
->ngpio
)
3554 return test_bit(FLAG_OPEN_DRAIN
, &chip
->gpiodev
->descs
[offset
].flags
);
3556 EXPORT_SYMBOL_GPL(gpiochip_line_is_open_drain
);
3558 bool gpiochip_line_is_open_source(struct gpio_chip
*chip
, unsigned int offset
)
3560 if (offset
>= chip
->ngpio
)
3563 return test_bit(FLAG_OPEN_SOURCE
, &chip
->gpiodev
->descs
[offset
].flags
);
3565 EXPORT_SYMBOL_GPL(gpiochip_line_is_open_source
);
3567 bool gpiochip_line_is_persistent(struct gpio_chip
*chip
, unsigned int offset
)
3569 if (offset
>= chip
->ngpio
)
3572 return !test_bit(FLAG_TRANSITORY
, &chip
->gpiodev
->descs
[offset
].flags
);
3574 EXPORT_SYMBOL_GPL(gpiochip_line_is_persistent
);
3577 * gpiod_get_raw_value_cansleep() - return a gpio's raw value
3578 * @desc: gpio whose value will be returned
3580 * Return the GPIO's raw value, i.e. the value of the physical line disregarding
3581 * its ACTIVE_LOW status, or negative errno on failure.
3583 * This function is to be called from contexts that can sleep.
3585 int gpiod_get_raw_value_cansleep(const struct gpio_desc
*desc
)
3587 might_sleep_if(extra_checks
);
3588 VALIDATE_DESC(desc
);
3589 return gpiod_get_raw_value_commit(desc
);
3591 EXPORT_SYMBOL_GPL(gpiod_get_raw_value_cansleep
);
3594 * gpiod_get_value_cansleep() - return a gpio's value
3595 * @desc: gpio whose value will be returned
3597 * Return the GPIO's logical value, i.e. taking the ACTIVE_LOW status into
3598 * account, or negative errno on failure.
3600 * This function is to be called from contexts that can sleep.
3602 int gpiod_get_value_cansleep(const struct gpio_desc
*desc
)
3606 might_sleep_if(extra_checks
);
3607 VALIDATE_DESC(desc
);
3608 value
= gpiod_get_raw_value_commit(desc
);
3612 if (test_bit(FLAG_ACTIVE_LOW
, &desc
->flags
))
3617 EXPORT_SYMBOL_GPL(gpiod_get_value_cansleep
);
3620 * gpiod_get_raw_array_value_cansleep() - read raw values from an array of GPIOs
3621 * @array_size: number of elements in the descriptor array / value bitmap
3622 * @desc_array: array of GPIO descriptors whose values will be read
3623 * @array_info: information on applicability of fast bitmap processing path
3624 * @value_bitmap: bitmap to store the read values
3626 * Read the raw values of the GPIOs, i.e. the values of the physical lines
3627 * without regard for their ACTIVE_LOW status. Return 0 in case of success,
3628 * else an error code.
3630 * This function is to be called from contexts that can sleep.
3632 int gpiod_get_raw_array_value_cansleep(unsigned int array_size
,
3633 struct gpio_desc
**desc_array
,
3634 struct gpio_array
*array_info
,
3635 unsigned long *value_bitmap
)
3637 might_sleep_if(extra_checks
);
3640 return gpiod_get_array_value_complex(true, true, array_size
,
3641 desc_array
, array_info
,
3644 EXPORT_SYMBOL_GPL(gpiod_get_raw_array_value_cansleep
);
3647 * gpiod_get_array_value_cansleep() - read values from an array of GPIOs
3648 * @array_size: number of elements in the descriptor array / value bitmap
3649 * @desc_array: array of GPIO descriptors whose values will be read
3650 * @array_info: information on applicability of fast bitmap processing path
3651 * @value_bitmap: bitmap to store the read values
3653 * Read the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status
3654 * into account. Return 0 in case of success, else an error code.
3656 * This function is to be called from contexts that can sleep.
3658 int gpiod_get_array_value_cansleep(unsigned int array_size
,
3659 struct gpio_desc
**desc_array
,
3660 struct gpio_array
*array_info
,
3661 unsigned long *value_bitmap
)
3663 might_sleep_if(extra_checks
);
3666 return gpiod_get_array_value_complex(false, true, array_size
,
3667 desc_array
, array_info
,
3670 EXPORT_SYMBOL_GPL(gpiod_get_array_value_cansleep
);
3673 * gpiod_set_raw_value_cansleep() - assign a gpio's raw value
3674 * @desc: gpio whose value will be assigned
3675 * @value: value to assign
3677 * Set the raw value of the GPIO, i.e. the value of its physical line without
3678 * regard for its ACTIVE_LOW status.
3680 * This function is to be called from contexts that can sleep.
3682 void gpiod_set_raw_value_cansleep(struct gpio_desc
*desc
, int value
)
3684 might_sleep_if(extra_checks
);
3685 VALIDATE_DESC_VOID(desc
);
3686 gpiod_set_raw_value_commit(desc
, value
);
3688 EXPORT_SYMBOL_GPL(gpiod_set_raw_value_cansleep
);
3691 * gpiod_set_value_cansleep() - assign a gpio's value
3692 * @desc: gpio whose value will be assigned
3693 * @value: value to assign
3695 * Set the logical value of the GPIO, i.e. taking its ACTIVE_LOW status into
3698 * This function is to be called from contexts that can sleep.
3700 void gpiod_set_value_cansleep(struct gpio_desc
*desc
, int value
)
3702 might_sleep_if(extra_checks
);
3703 VALIDATE_DESC_VOID(desc
);
3704 gpiod_set_value_nocheck(desc
, value
);
3706 EXPORT_SYMBOL_GPL(gpiod_set_value_cansleep
);
3709 * gpiod_set_raw_array_value_cansleep() - assign values to an array of GPIOs
3710 * @array_size: number of elements in the descriptor array / value bitmap
3711 * @desc_array: array of GPIO descriptors whose values will be assigned
3712 * @array_info: information on applicability of fast bitmap processing path
3713 * @value_bitmap: bitmap of values to assign
3715 * Set the raw values of the GPIOs, i.e. the values of the physical lines
3716 * without regard for their ACTIVE_LOW status.
3718 * This function is to be called from contexts that can sleep.
3720 int gpiod_set_raw_array_value_cansleep(unsigned int array_size
,
3721 struct gpio_desc
**desc_array
,
3722 struct gpio_array
*array_info
,
3723 unsigned long *value_bitmap
)
3725 might_sleep_if(extra_checks
);
3728 return gpiod_set_array_value_complex(true, true, array_size
, desc_array
,
3729 array_info
, value_bitmap
);
3731 EXPORT_SYMBOL_GPL(gpiod_set_raw_array_value_cansleep
);
3734 * gpiod_add_lookup_tables() - register GPIO device consumers
3735 * @tables: list of tables of consumers to register
3736 * @n: number of tables in the list
3738 void gpiod_add_lookup_tables(struct gpiod_lookup_table
**tables
, size_t n
)
3742 mutex_lock(&gpio_lookup_lock
);
3744 for (i
= 0; i
< n
; i
++)
3745 list_add_tail(&tables
[i
]->list
, &gpio_lookup_list
);
3747 mutex_unlock(&gpio_lookup_lock
);
3751 * gpiod_set_array_value_cansleep() - assign values to an array of GPIOs
3752 * @array_size: number of elements in the descriptor array / value bitmap
3753 * @desc_array: array of GPIO descriptors whose values will be assigned
3754 * @array_info: information on applicability of fast bitmap processing path
3755 * @value_bitmap: bitmap of values to assign
3757 * Set the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status
3760 * This function is to be called from contexts that can sleep.
3762 int gpiod_set_array_value_cansleep(unsigned int array_size
,
3763 struct gpio_desc
**desc_array
,
3764 struct gpio_array
*array_info
,
3765 unsigned long *value_bitmap
)
3767 might_sleep_if(extra_checks
);
3770 return gpiod_set_array_value_complex(false, true, array_size
,
3771 desc_array
, array_info
,
3774 EXPORT_SYMBOL_GPL(gpiod_set_array_value_cansleep
);
3777 * gpiod_add_lookup_table() - register GPIO device consumers
3778 * @table: table of consumers to register
3780 void gpiod_add_lookup_table(struct gpiod_lookup_table
*table
)
3782 mutex_lock(&gpio_lookup_lock
);
3784 list_add_tail(&table
->list
, &gpio_lookup_list
);
3786 mutex_unlock(&gpio_lookup_lock
);
3788 EXPORT_SYMBOL_GPL(gpiod_add_lookup_table
);
3791 * gpiod_remove_lookup_table() - unregister GPIO device consumers
3792 * @table: table of consumers to unregister
3794 void gpiod_remove_lookup_table(struct gpiod_lookup_table
*table
)
3796 mutex_lock(&gpio_lookup_lock
);
3798 list_del(&table
->list
);
3800 mutex_unlock(&gpio_lookup_lock
);
3802 EXPORT_SYMBOL_GPL(gpiod_remove_lookup_table
);
3805 * gpiod_add_hogs() - register a set of GPIO hogs from machine code
3806 * @hogs: table of gpio hog entries with a zeroed sentinel at the end
3808 void gpiod_add_hogs(struct gpiod_hog
*hogs
)
3810 struct gpio_chip
*chip
;
3811 struct gpiod_hog
*hog
;
3813 mutex_lock(&gpio_machine_hogs_mutex
);
3815 for (hog
= &hogs
[0]; hog
->chip_label
; hog
++) {
3816 list_add_tail(&hog
->list
, &gpio_machine_hogs
);
3819 * The chip may have been registered earlier, so check if it
3820 * exists and, if so, try to hog the line now.
3822 chip
= find_chip_by_name(hog
->chip_label
);
3824 gpiochip_machine_hog(chip
, hog
);
3827 mutex_unlock(&gpio_machine_hogs_mutex
);
3829 EXPORT_SYMBOL_GPL(gpiod_add_hogs
);
3831 static struct gpiod_lookup_table
*gpiod_find_lookup_table(struct device
*dev
)
3833 const char *dev_id
= dev
? dev_name(dev
) : NULL
;
3834 struct gpiod_lookup_table
*table
;
3836 mutex_lock(&gpio_lookup_lock
);
3838 list_for_each_entry(table
, &gpio_lookup_list
, list
) {
3839 if (table
->dev_id
&& dev_id
) {
3841 * Valid strings on both ends, must be identical to have
3844 if (!strcmp(table
->dev_id
, dev_id
))
3848 * One of the pointers is NULL, so both must be to have
3851 if (dev_id
== table
->dev_id
)
3858 mutex_unlock(&gpio_lookup_lock
);
3862 static struct gpio_desc
*gpiod_find(struct device
*dev
, const char *con_id
,
3864 enum gpio_lookup_flags
*flags
)
3866 struct gpio_desc
*desc
= ERR_PTR(-ENOENT
);
3867 struct gpiod_lookup_table
*table
;
3868 struct gpiod_lookup
*p
;
3870 table
= gpiod_find_lookup_table(dev
);
3874 for (p
= &table
->table
[0]; p
->chip_label
; p
++) {
3875 struct gpio_chip
*chip
;
3877 /* idx must always match exactly */
3881 /* If the lookup entry has a con_id, require exact match */
3882 if (p
->con_id
&& (!con_id
|| strcmp(p
->con_id
, con_id
)))
3885 chip
= find_chip_by_name(p
->chip_label
);
3889 * As the lookup table indicates a chip with
3890 * p->chip_label should exist, assume it may
3891 * still appear later and let the interested
3892 * consumer be probed again or let the Deferred
3893 * Probe infrastructure handle the error.
3895 dev_warn(dev
, "cannot find GPIO chip %s, deferring\n",
3897 return ERR_PTR(-EPROBE_DEFER
);
3900 if (chip
->ngpio
<= p
->chip_hwnum
) {
3902 "requested GPIO %d is out of range [0..%d] for chip %s\n",
3903 idx
, chip
->ngpio
, chip
->label
);
3904 return ERR_PTR(-EINVAL
);
3907 desc
= gpiochip_get_desc(chip
, p
->chip_hwnum
);
3916 static int dt_gpio_count(struct device
*dev
, const char *con_id
)
3922 for (i
= 0; i
< ARRAY_SIZE(gpio_suffixes
); i
++) {
3924 snprintf(propname
, sizeof(propname
), "%s-%s",
3925 con_id
, gpio_suffixes
[i
]);
3927 snprintf(propname
, sizeof(propname
), "%s",
3930 ret
= of_gpio_named_count(dev
->of_node
, propname
);
3934 return ret
? ret
: -ENOENT
;
3937 static int platform_gpio_count(struct device
*dev
, const char *con_id
)
3939 struct gpiod_lookup_table
*table
;
3940 struct gpiod_lookup
*p
;
3941 unsigned int count
= 0;
3943 table
= gpiod_find_lookup_table(dev
);
3947 for (p
= &table
->table
[0]; p
->chip_label
; p
++) {
3948 if ((con_id
&& p
->con_id
&& !strcmp(con_id
, p
->con_id
)) ||
3949 (!con_id
&& !p
->con_id
))
3959 * gpiod_count - return the number of GPIOs associated with a device / function
3960 * or -ENOENT if no GPIO has been assigned to the requested function
3961 * @dev: GPIO consumer, can be NULL for system-global GPIOs
3962 * @con_id: function within the GPIO consumer
3964 int gpiod_count(struct device
*dev
, const char *con_id
)
3966 int count
= -ENOENT
;
3968 if (IS_ENABLED(CONFIG_OF
) && dev
&& dev
->of_node
)
3969 count
= dt_gpio_count(dev
, con_id
);
3970 else if (IS_ENABLED(CONFIG_ACPI
) && dev
&& ACPI_HANDLE(dev
))
3971 count
= acpi_gpio_count(dev
, con_id
);
3974 count
= platform_gpio_count(dev
, con_id
);
3978 EXPORT_SYMBOL_GPL(gpiod_count
);
3981 * gpiod_get - obtain a GPIO for a given GPIO function
3982 * @dev: GPIO consumer, can be NULL for system-global GPIOs
3983 * @con_id: function within the GPIO consumer
3984 * @flags: optional GPIO initialization flags
3986 * Return the GPIO descriptor corresponding to the function con_id of device
3987 * dev, -ENOENT if no GPIO has been assigned to the requested function, or
3988 * another IS_ERR() code if an error occurred while trying to acquire the GPIO.
3990 struct gpio_desc
*__must_check
gpiod_get(struct device
*dev
, const char *con_id
,
3991 enum gpiod_flags flags
)
3993 return gpiod_get_index(dev
, con_id
, 0, flags
);
3995 EXPORT_SYMBOL_GPL(gpiod_get
);
3998 * gpiod_get_optional - obtain an optional GPIO for a given GPIO function
3999 * @dev: GPIO consumer, can be NULL for system-global GPIOs
4000 * @con_id: function within the GPIO consumer
4001 * @flags: optional GPIO initialization flags
4003 * This is equivalent to gpiod_get(), except that when no GPIO was assigned to
4004 * the requested function it will return NULL. This is convenient for drivers
4005 * that need to handle optional GPIOs.
4007 struct gpio_desc
*__must_check
gpiod_get_optional(struct device
*dev
,
4009 enum gpiod_flags flags
)
4011 return gpiod_get_index_optional(dev
, con_id
, 0, flags
);
4013 EXPORT_SYMBOL_GPL(gpiod_get_optional
);
4017 * gpiod_configure_flags - helper function to configure a given GPIO
4018 * @desc: gpio whose value will be assigned
4019 * @con_id: function within the GPIO consumer
4020 * @lflags: gpio_lookup_flags - returned from of_find_gpio() or
4022 * @dflags: gpiod_flags - optional GPIO initialization flags
4024 * Return 0 on success, -ENOENT if no GPIO has been assigned to the
4025 * requested function and/or index, or another IS_ERR() code if an error
4026 * occurred while trying to acquire the GPIO.
4028 int gpiod_configure_flags(struct gpio_desc
*desc
, const char *con_id
,
4029 unsigned long lflags
, enum gpiod_flags dflags
)
4033 if (lflags
& GPIO_ACTIVE_LOW
)
4034 set_bit(FLAG_ACTIVE_LOW
, &desc
->flags
);
4036 if (lflags
& GPIO_OPEN_DRAIN
)
4037 set_bit(FLAG_OPEN_DRAIN
, &desc
->flags
);
4038 else if (dflags
& GPIOD_FLAGS_BIT_OPEN_DRAIN
) {
4040 * This enforces open drain mode from the consumer side.
4041 * This is necessary for some busses like I2C, but the lookup
4042 * should *REALLY* have specified them as open drain in the
4043 * first place, so print a little warning here.
4045 set_bit(FLAG_OPEN_DRAIN
, &desc
->flags
);
4047 "enforced open drain please flag it properly in DT/ACPI DSDT/board file\n");
4050 if (lflags
& GPIO_OPEN_SOURCE
)
4051 set_bit(FLAG_OPEN_SOURCE
, &desc
->flags
);
4053 status
= gpiod_set_transitory(desc
, (lflags
& GPIO_TRANSITORY
));
4057 /* No particular flag request, return here... */
4058 if (!(dflags
& GPIOD_FLAGS_BIT_DIR_SET
)) {
4059 pr_debug("no flags found for %s\n", con_id
);
4064 if (dflags
& GPIOD_FLAGS_BIT_DIR_OUT
)
4065 status
= gpiod_direction_output(desc
,
4066 !!(dflags
& GPIOD_FLAGS_BIT_DIR_VAL
));
4068 status
= gpiod_direction_input(desc
);
4074 * gpiod_get_index - obtain a GPIO from a multi-index GPIO function
4075 * @dev: GPIO consumer, can be NULL for system-global GPIOs
4076 * @con_id: function within the GPIO consumer
4077 * @idx: index of the GPIO to obtain in the consumer
4078 * @flags: optional GPIO initialization flags
4080 * This variant of gpiod_get() allows to access GPIOs other than the first
4081 * defined one for functions that define several GPIOs.
4083 * Return a valid GPIO descriptor, -ENOENT if no GPIO has been assigned to the
4084 * requested function and/or index, or another IS_ERR() code if an error
4085 * occurred while trying to acquire the GPIO.
4087 struct gpio_desc
*__must_check
gpiod_get_index(struct device
*dev
,
4090 enum gpiod_flags flags
)
4092 struct gpio_desc
*desc
= NULL
;
4094 enum gpio_lookup_flags lookupflags
= 0;
4095 /* Maybe we have a device name, maybe not */
4096 const char *devname
= dev
? dev_name(dev
) : "?";
4098 dev_dbg(dev
, "GPIO lookup for consumer %s\n", con_id
);
4101 /* Using device tree? */
4102 if (IS_ENABLED(CONFIG_OF
) && dev
->of_node
) {
4103 dev_dbg(dev
, "using device tree for GPIO lookup\n");
4104 desc
= of_find_gpio(dev
, con_id
, idx
, &lookupflags
);
4105 } else if (ACPI_COMPANION(dev
)) {
4106 dev_dbg(dev
, "using ACPI for GPIO lookup\n");
4107 desc
= acpi_find_gpio(dev
, con_id
, idx
, &flags
, &lookupflags
);
4112 * Either we are not using DT or ACPI, or their lookup did not return
4113 * a result. In that case, use platform lookup as a fallback.
4115 if (!desc
|| desc
== ERR_PTR(-ENOENT
)) {
4116 dev_dbg(dev
, "using lookup tables for GPIO lookup\n");
4117 desc
= gpiod_find(dev
, con_id
, idx
, &lookupflags
);
4121 dev_dbg(dev
, "No GPIO consumer %s found\n", con_id
);
4126 * If a connection label was passed use that, else attempt to use
4127 * the device name as label
4129 status
= gpiod_request(desc
, con_id
? con_id
: devname
);
4131 if (status
== -EBUSY
&& flags
& GPIOD_FLAGS_BIT_NONEXCLUSIVE
) {
4133 * This happens when there are several consumers for
4134 * the same GPIO line: we just return here without
4135 * further initialization. It is a bit if a hack.
4136 * This is necessary to support fixed regulators.
4138 * FIXME: Make this more sane and safe.
4140 dev_info(dev
, "nonexclusive access to GPIO for %s\n",
4141 con_id
? con_id
: devname
);
4144 return ERR_PTR(status
);
4148 status
= gpiod_configure_flags(desc
, con_id
, lookupflags
, flags
);
4150 dev_dbg(dev
, "setup of GPIO %s failed\n", con_id
);
4152 return ERR_PTR(status
);
4157 EXPORT_SYMBOL_GPL(gpiod_get_index
);
4160 * gpiod_get_from_of_node() - obtain a GPIO from an OF node
4161 * @node: handle of the OF node
4162 * @propname: name of the DT property representing the GPIO
4163 * @index: index of the GPIO to obtain for the consumer
4164 * @dflags: GPIO initialization flags
4165 * @label: label to attach to the requested GPIO
4168 * On successful request the GPIO pin is configured in accordance with
4169 * provided @dflags. If the node does not have the requested GPIO
4170 * property, NULL is returned.
4172 * In case of error an ERR_PTR() is returned.
4174 struct gpio_desc
*gpiod_get_from_of_node(struct device_node
*node
,
4175 const char *propname
, int index
,
4176 enum gpiod_flags dflags
,
4179 struct gpio_desc
*desc
;
4180 unsigned long lflags
= 0;
4181 enum of_gpio_flags flags
;
4182 bool active_low
= false;
4183 bool single_ended
= false;
4184 bool open_drain
= false;
4185 bool transitory
= false;
4188 desc
= of_get_named_gpiod_flags(node
, propname
,
4191 if (!desc
|| IS_ERR(desc
)) {
4192 /* If it is not there, just return NULL */
4193 if (PTR_ERR(desc
) == -ENOENT
)
4198 active_low
= flags
& OF_GPIO_ACTIVE_LOW
;
4199 single_ended
= flags
& OF_GPIO_SINGLE_ENDED
;
4200 open_drain
= flags
& OF_GPIO_OPEN_DRAIN
;
4201 transitory
= flags
& OF_GPIO_TRANSITORY
;
4203 ret
= gpiod_request(desc
, label
);
4204 if (ret
== -EBUSY
&& (flags
& GPIOD_FLAGS_BIT_NONEXCLUSIVE
))
4207 return ERR_PTR(ret
);
4210 lflags
|= GPIO_ACTIVE_LOW
;
4214 lflags
|= GPIO_OPEN_DRAIN
;
4216 lflags
|= GPIO_OPEN_SOURCE
;
4220 lflags
|= GPIO_TRANSITORY
;
4222 ret
= gpiod_configure_flags(desc
, propname
, lflags
, dflags
);
4225 return ERR_PTR(ret
);
4230 EXPORT_SYMBOL(gpiod_get_from_of_node
);
4233 * fwnode_get_named_gpiod - obtain a GPIO from firmware node
4234 * @fwnode: handle of the firmware node
4235 * @propname: name of the firmware property representing the GPIO
4236 * @index: index of the GPIO to obtain for the consumer
4237 * @dflags: GPIO initialization flags
4238 * @label: label to attach to the requested GPIO
4240 * This function can be used for drivers that get their configuration
4241 * from opaque firmware.
4243 * The function properly finds the corresponding GPIO using whatever is the
4244 * underlying firmware interface and then makes sure that the GPIO
4245 * descriptor is requested before it is returned to the caller.
4248 * On successful request the GPIO pin is configured in accordance with
4251 * In case of error an ERR_PTR() is returned.
4253 struct gpio_desc
*fwnode_get_named_gpiod(struct fwnode_handle
*fwnode
,
4254 const char *propname
, int index
,
4255 enum gpiod_flags dflags
,
4258 struct gpio_desc
*desc
= ERR_PTR(-ENODEV
);
4259 unsigned long lflags
= 0;
4263 return ERR_PTR(-EINVAL
);
4265 if (is_of_node(fwnode
)) {
4266 desc
= gpiod_get_from_of_node(to_of_node(fwnode
),
4271 } else if (is_acpi_node(fwnode
)) {
4272 struct acpi_gpio_info info
;
4274 desc
= acpi_node_get_gpiod(fwnode
, propname
, index
, &info
);
4278 acpi_gpio_update_gpiod_flags(&dflags
, &info
);
4280 if (info
.polarity
== GPIO_ACTIVE_LOW
)
4281 lflags
|= GPIO_ACTIVE_LOW
;
4284 /* Currently only ACPI takes this path */
4285 ret
= gpiod_request(desc
, label
);
4287 return ERR_PTR(ret
);
4289 ret
= gpiod_configure_flags(desc
, propname
, lflags
, dflags
);
4292 return ERR_PTR(ret
);
4297 EXPORT_SYMBOL_GPL(fwnode_get_named_gpiod
);
4300 * gpiod_get_index_optional - obtain an optional GPIO from a multi-index GPIO
4302 * @dev: GPIO consumer, can be NULL for system-global GPIOs
4303 * @con_id: function within the GPIO consumer
4304 * @index: index of the GPIO to obtain in the consumer
4305 * @flags: optional GPIO initialization flags
4307 * This is equivalent to gpiod_get_index(), except that when no GPIO with the
4308 * specified index was assigned to the requested function it will return NULL.
4309 * This is convenient for drivers that need to handle optional GPIOs.
4311 struct gpio_desc
*__must_check
gpiod_get_index_optional(struct device
*dev
,
4314 enum gpiod_flags flags
)
4316 struct gpio_desc
*desc
;
4318 desc
= gpiod_get_index(dev
, con_id
, index
, flags
);
4320 if (PTR_ERR(desc
) == -ENOENT
)
4326 EXPORT_SYMBOL_GPL(gpiod_get_index_optional
);
4329 * gpiod_hog - Hog the specified GPIO desc given the provided flags
4330 * @desc: gpio whose value will be assigned
4331 * @name: gpio line name
4332 * @lflags: gpio_lookup_flags - returned from of_find_gpio() or
4334 * @dflags: gpiod_flags - optional GPIO initialization flags
4336 int gpiod_hog(struct gpio_desc
*desc
, const char *name
,
4337 unsigned long lflags
, enum gpiod_flags dflags
)
4339 struct gpio_chip
*chip
;
4340 struct gpio_desc
*local_desc
;
4344 chip
= gpiod_to_chip(desc
);
4345 hwnum
= gpio_chip_hwgpio(desc
);
4348 * FIXME: not very elegant that we call gpiod_configure_flags()
4349 * twice here (once inside gpiochip_request_own_desc() and
4350 * again here), but the gpiochip_request_own_desc() is external
4351 * and cannot really pass the lflags so this is the lesser evil
4352 * at the moment. Pass zero as dflags on this first call so we
4353 * don't screw anything up.
4355 local_desc
= gpiochip_request_own_desc(chip
, hwnum
, name
, 0);
4356 if (IS_ERR(local_desc
)) {
4357 status
= PTR_ERR(local_desc
);
4358 pr_err("requesting hog GPIO %s (chip %s, offset %d) failed, %d\n",
4359 name
, chip
->label
, hwnum
, status
);
4363 status
= gpiod_configure_flags(desc
, name
, lflags
, dflags
);
4365 pr_err("setup of hog GPIO %s (chip %s, offset %d) failed, %d\n",
4366 name
, chip
->label
, hwnum
, status
);
4367 gpiochip_free_own_desc(desc
);
4371 /* Mark GPIO as hogged so it can be identified and removed later */
4372 set_bit(FLAG_IS_HOGGED
, &desc
->flags
);
4374 pr_info("GPIO line %d (%s) hogged as %s%s\n",
4375 desc_to_gpio(desc
), name
,
4376 (dflags
&GPIOD_FLAGS_BIT_DIR_OUT
) ? "output" : "input",
4377 (dflags
&GPIOD_FLAGS_BIT_DIR_OUT
) ?
4378 (dflags
&GPIOD_FLAGS_BIT_DIR_VAL
) ? "/high" : "/low":"");
4384 * gpiochip_free_hogs - Scan gpio-controller chip and release GPIO hog
4385 * @chip: gpio chip to act on
4387 * This is only used by of_gpiochip_remove to free hogged gpios
4389 static void gpiochip_free_hogs(struct gpio_chip
*chip
)
4393 for (id
= 0; id
< chip
->ngpio
; id
++) {
4394 if (test_bit(FLAG_IS_HOGGED
, &chip
->gpiodev
->descs
[id
].flags
))
4395 gpiochip_free_own_desc(&chip
->gpiodev
->descs
[id
]);
4400 * gpiod_get_array - obtain multiple GPIOs from a multi-index GPIO function
4401 * @dev: GPIO consumer, can be NULL for system-global GPIOs
4402 * @con_id: function within the GPIO consumer
4403 * @flags: optional GPIO initialization flags
4405 * This function acquires all the GPIOs defined under a given function.
4407 * Return a struct gpio_descs containing an array of descriptors, -ENOENT if
4408 * no GPIO has been assigned to the requested function, or another IS_ERR()
4409 * code if an error occurred while trying to acquire the GPIOs.
4411 struct gpio_descs
*__must_check
gpiod_get_array(struct device
*dev
,
4413 enum gpiod_flags flags
)
4415 struct gpio_desc
*desc
;
4416 struct gpio_descs
*descs
;
4417 struct gpio_array
*array_info
= NULL
;
4418 struct gpio_chip
*chip
;
4419 int count
, bitmap_size
;
4421 count
= gpiod_count(dev
, con_id
);
4423 return ERR_PTR(count
);
4425 descs
= kzalloc(struct_size(descs
, desc
, count
), GFP_KERNEL
);
4427 return ERR_PTR(-ENOMEM
);
4429 for (descs
->ndescs
= 0; descs
->ndescs
< count
; ) {
4430 desc
= gpiod_get_index(dev
, con_id
, descs
->ndescs
, flags
);
4432 gpiod_put_array(descs
);
4433 return ERR_CAST(desc
);
4436 descs
->desc
[descs
->ndescs
] = desc
;
4438 chip
= gpiod_to_chip(desc
);
4440 * If pin hardware number of array member 0 is also 0, select
4441 * its chip as a candidate for fast bitmap processing path.
4443 if (descs
->ndescs
== 0 && gpio_chip_hwgpio(desc
) == 0) {
4444 struct gpio_descs
*array
;
4446 bitmap_size
= BITS_TO_LONGS(chip
->ngpio
> count
?
4447 chip
->ngpio
: count
);
4449 array
= kzalloc(struct_size(descs
, desc
, count
) +
4450 struct_size(array_info
, invert_mask
,
4451 3 * bitmap_size
), GFP_KERNEL
);
4453 gpiod_put_array(descs
);
4454 return ERR_PTR(-ENOMEM
);
4457 memcpy(array
, descs
,
4458 struct_size(descs
, desc
, descs
->ndescs
+ 1));
4462 array_info
= (void *)(descs
->desc
+ count
);
4463 array_info
->get_mask
= array_info
->invert_mask
+
4465 array_info
->set_mask
= array_info
->get_mask
+
4468 array_info
->desc
= descs
->desc
;
4469 array_info
->size
= count
;
4470 array_info
->chip
= chip
;
4471 bitmap_set(array_info
->get_mask
, descs
->ndescs
,
4472 count
- descs
->ndescs
);
4473 bitmap_set(array_info
->set_mask
, descs
->ndescs
,
4474 count
- descs
->ndescs
);
4475 descs
->info
= array_info
;
4477 /* Unmark array members which don't belong to the 'fast' chip */
4478 if (array_info
&& array_info
->chip
!= chip
) {
4479 __clear_bit(descs
->ndescs
, array_info
->get_mask
);
4480 __clear_bit(descs
->ndescs
, array_info
->set_mask
);
4483 * Detect array members which belong to the 'fast' chip
4484 * but their pins are not in hardware order.
4486 else if (array_info
&&
4487 gpio_chip_hwgpio(desc
) != descs
->ndescs
) {
4489 * Don't use fast path if all array members processed so
4490 * far belong to the same chip as this one but its pin
4491 * hardware number is different from its array index.
4493 if (bitmap_full(array_info
->get_mask
, descs
->ndescs
)) {
4496 __clear_bit(descs
->ndescs
,
4497 array_info
->get_mask
);
4498 __clear_bit(descs
->ndescs
,
4499 array_info
->set_mask
);
4501 } else if (array_info
) {
4502 /* Exclude open drain or open source from fast output */
4503 if (gpiochip_line_is_open_drain(chip
, descs
->ndescs
) ||
4504 gpiochip_line_is_open_source(chip
, descs
->ndescs
))
4505 __clear_bit(descs
->ndescs
,
4506 array_info
->set_mask
);
4507 /* Identify 'fast' pins which require invertion */
4508 if (gpiod_is_active_low(desc
))
4509 __set_bit(descs
->ndescs
,
4510 array_info
->invert_mask
);
4517 "GPIO array info: chip=%s, size=%d, get_mask=%lx, set_mask=%lx, invert_mask=%lx\n",
4518 array_info
->chip
->label
, array_info
->size
,
4519 *array_info
->get_mask
, *array_info
->set_mask
,
4520 *array_info
->invert_mask
);
4523 EXPORT_SYMBOL_GPL(gpiod_get_array
);
4526 * gpiod_get_array_optional - obtain multiple GPIOs from a multi-index GPIO
4528 * @dev: GPIO consumer, can be NULL for system-global GPIOs
4529 * @con_id: function within the GPIO consumer
4530 * @flags: optional GPIO initialization flags
4532 * This is equivalent to gpiod_get_array(), except that when no GPIO was
4533 * assigned to the requested function it will return NULL.
4535 struct gpio_descs
*__must_check
gpiod_get_array_optional(struct device
*dev
,
4537 enum gpiod_flags flags
)
4539 struct gpio_descs
*descs
;
4541 descs
= gpiod_get_array(dev
, con_id
, flags
);
4542 if (IS_ERR(descs
) && (PTR_ERR(descs
) == -ENOENT
))
4547 EXPORT_SYMBOL_GPL(gpiod_get_array_optional
);
4550 * gpiod_put - dispose of a GPIO descriptor
4551 * @desc: GPIO descriptor to dispose of
4553 * No descriptor can be used after gpiod_put() has been called on it.
4555 void gpiod_put(struct gpio_desc
*desc
)
4559 EXPORT_SYMBOL_GPL(gpiod_put
);
4562 * gpiod_put_array - dispose of multiple GPIO descriptors
4563 * @descs: struct gpio_descs containing an array of descriptors
4565 void gpiod_put_array(struct gpio_descs
*descs
)
4569 for (i
= 0; i
< descs
->ndescs
; i
++)
4570 gpiod_put(descs
->desc
[i
]);
4574 EXPORT_SYMBOL_GPL(gpiod_put_array
);
4576 static int __init
gpiolib_dev_init(void)
4580 /* Register GPIO sysfs bus */
4581 ret
= bus_register(&gpio_bus_type
);
4583 pr_err("gpiolib: could not register GPIO bus type\n");
4587 ret
= alloc_chrdev_region(&gpio_devt
, 0, GPIO_DEV_MAX
, "gpiochip");
4589 pr_err("gpiolib: failed to allocate char dev region\n");
4590 bus_unregister(&gpio_bus_type
);
4592 gpiolib_initialized
= true;
4593 gpiochip_setup_devs();
4597 core_initcall(gpiolib_dev_init
);
4599 #ifdef CONFIG_DEBUG_FS
4601 static void gpiolib_dbg_show(struct seq_file
*s
, struct gpio_device
*gdev
)
4604 struct gpio_chip
*chip
= gdev
->chip
;
4605 unsigned gpio
= gdev
->base
;
4606 struct gpio_desc
*gdesc
= &gdev
->descs
[0];
4611 for (i
= 0; i
< gdev
->ngpio
; i
++, gpio
++, gdesc
++) {
4612 if (!test_bit(FLAG_REQUESTED
, &gdesc
->flags
)) {
4614 seq_printf(s
, " gpio-%-3d (%-20.20s)\n",
4620 gpiod_get_direction(gdesc
);
4621 is_out
= test_bit(FLAG_IS_OUT
, &gdesc
->flags
);
4622 is_irq
= test_bit(FLAG_USED_AS_IRQ
, &gdesc
->flags
);
4623 active_low
= test_bit(FLAG_ACTIVE_LOW
, &gdesc
->flags
);
4624 seq_printf(s
, " gpio-%-3d (%-20.20s|%-20.20s) %s %s %s%s",
4625 gpio
, gdesc
->name
? gdesc
->name
: "", gdesc
->label
,
4626 is_out
? "out" : "in ",
4627 chip
->get
? (chip
->get(chip
, i
) ? "hi" : "lo") : "? ",
4628 is_irq
? "IRQ " : "",
4629 active_low
? "ACTIVE LOW" : "");
4630 seq_printf(s
, "\n");
4634 static void *gpiolib_seq_start(struct seq_file
*s
, loff_t
*pos
)
4636 unsigned long flags
;
4637 struct gpio_device
*gdev
= NULL
;
4638 loff_t index
= *pos
;
4642 spin_lock_irqsave(&gpio_lock
, flags
);
4643 list_for_each_entry(gdev
, &gpio_devices
, list
)
4645 spin_unlock_irqrestore(&gpio_lock
, flags
);
4648 spin_unlock_irqrestore(&gpio_lock
, flags
);
4653 static void *gpiolib_seq_next(struct seq_file
*s
, void *v
, loff_t
*pos
)
4655 unsigned long flags
;
4656 struct gpio_device
*gdev
= v
;
4659 spin_lock_irqsave(&gpio_lock
, flags
);
4660 if (list_is_last(&gdev
->list
, &gpio_devices
))
4663 ret
= list_entry(gdev
->list
.next
, struct gpio_device
, list
);
4664 spin_unlock_irqrestore(&gpio_lock
, flags
);
4672 static void gpiolib_seq_stop(struct seq_file
*s
, void *v
)
4676 static int gpiolib_seq_show(struct seq_file
*s
, void *v
)
4678 struct gpio_device
*gdev
= v
;
4679 struct gpio_chip
*chip
= gdev
->chip
;
4680 struct device
*parent
;
4683 seq_printf(s
, "%s%s: (dangling chip)", (char *)s
->private,
4684 dev_name(&gdev
->dev
));
4688 seq_printf(s
, "%s%s: GPIOs %d-%d", (char *)s
->private,
4689 dev_name(&gdev
->dev
),
4690 gdev
->base
, gdev
->base
+ gdev
->ngpio
- 1);
4691 parent
= chip
->parent
;
4693 seq_printf(s
, ", parent: %s/%s",
4694 parent
->bus
? parent
->bus
->name
: "no-bus",
4697 seq_printf(s
, ", %s", chip
->label
);
4698 if (chip
->can_sleep
)
4699 seq_printf(s
, ", can sleep");
4700 seq_printf(s
, ":\n");
4703 chip
->dbg_show(s
, chip
);
4705 gpiolib_dbg_show(s
, gdev
);
4710 static const struct seq_operations gpiolib_seq_ops
= {
4711 .start
= gpiolib_seq_start
,
4712 .next
= gpiolib_seq_next
,
4713 .stop
= gpiolib_seq_stop
,
4714 .show
= gpiolib_seq_show
,
4717 static int gpiolib_open(struct inode
*inode
, struct file
*file
)
4719 return seq_open(file
, &gpiolib_seq_ops
);
4722 static const struct file_operations gpiolib_operations
= {
4723 .owner
= THIS_MODULE
,
4724 .open
= gpiolib_open
,
4726 .llseek
= seq_lseek
,
4727 .release
= seq_release
,
4730 static int __init
gpiolib_debugfs_init(void)
4732 /* /sys/kernel/debug/gpio */
4733 (void) debugfs_create_file("gpio", S_IFREG
| S_IRUGO
,
4734 NULL
, NULL
, &gpiolib_operations
);
4737 subsys_initcall(gpiolib_debugfs_init
);
4739 #endif /* DEBUG_FS */