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
));
832 * We may be running from a nested threaded interrupt in which case
833 * we didn't get the timestamp from lineevent_irq_handler().
836 ge
.timestamp
= ktime_get_real_ns();
838 ge
.timestamp
= le
->timestamp
;
840 if (le
->eflags
& GPIOEVENT_REQUEST_RISING_EDGE
841 && le
->eflags
& GPIOEVENT_REQUEST_FALLING_EDGE
) {
842 int level
= gpiod_get_value_cansleep(le
->desc
);
844 /* Emit low-to-high event */
845 ge
.id
= GPIOEVENT_EVENT_RISING_EDGE
;
847 /* Emit high-to-low event */
848 ge
.id
= GPIOEVENT_EVENT_FALLING_EDGE
;
849 } else if (le
->eflags
& GPIOEVENT_REQUEST_RISING_EDGE
) {
850 /* Emit low-to-high event */
851 ge
.id
= GPIOEVENT_EVENT_RISING_EDGE
;
852 } else if (le
->eflags
& GPIOEVENT_REQUEST_FALLING_EDGE
) {
853 /* Emit high-to-low event */
854 ge
.id
= GPIOEVENT_EVENT_FALLING_EDGE
;
859 ret
= kfifo_put(&le
->events
, ge
);
861 wake_up_poll(&le
->wait
, EPOLLIN
);
866 static irqreturn_t
lineevent_irq_handler(int irq
, void *p
)
868 struct lineevent_state
*le
= p
;
871 * Just store the timestamp in hardirq context so we get it as
872 * close in time as possible to the actual event.
874 le
->timestamp
= ktime_get_real_ns();
876 return IRQ_WAKE_THREAD
;
879 static int lineevent_create(struct gpio_device
*gdev
, void __user
*ip
)
881 struct gpioevent_request eventreq
;
882 struct lineevent_state
*le
;
883 struct gpio_desc
*desc
;
892 if (copy_from_user(&eventreq
, ip
, sizeof(eventreq
)))
895 le
= kzalloc(sizeof(*le
), GFP_KERNEL
);
899 get_device(&gdev
->dev
);
901 /* Make sure this is terminated */
902 eventreq
.consumer_label
[sizeof(eventreq
.consumer_label
)-1] = '\0';
903 if (strlen(eventreq
.consumer_label
)) {
904 le
->label
= kstrdup(eventreq
.consumer_label
,
912 offset
= eventreq
.lineoffset
;
913 lflags
= eventreq
.handleflags
;
914 eflags
= eventreq
.eventflags
;
916 if (offset
>= gdev
->ngpio
) {
921 /* Return an error if a unknown flag is set */
922 if ((lflags
& ~GPIOHANDLE_REQUEST_VALID_FLAGS
) ||
923 (eflags
& ~GPIOEVENT_REQUEST_VALID_FLAGS
)) {
928 /* This is just wrong: we don't look for events on output lines */
929 if (lflags
& GPIOHANDLE_REQUEST_OUTPUT
) {
934 desc
= &gdev
->descs
[offset
];
935 ret
= gpiod_request(desc
, le
->label
);
941 if (lflags
& GPIOHANDLE_REQUEST_ACTIVE_LOW
)
942 set_bit(FLAG_ACTIVE_LOW
, &desc
->flags
);
943 if (lflags
& GPIOHANDLE_REQUEST_OPEN_DRAIN
)
944 set_bit(FLAG_OPEN_DRAIN
, &desc
->flags
);
945 if (lflags
& GPIOHANDLE_REQUEST_OPEN_SOURCE
)
946 set_bit(FLAG_OPEN_SOURCE
, &desc
->flags
);
948 ret
= gpiod_direction_input(desc
);
952 le
->irq
= gpiod_to_irq(desc
);
958 if (eflags
& GPIOEVENT_REQUEST_RISING_EDGE
)
959 irqflags
|= IRQF_TRIGGER_RISING
;
960 if (eflags
& GPIOEVENT_REQUEST_FALLING_EDGE
)
961 irqflags
|= IRQF_TRIGGER_FALLING
;
962 irqflags
|= IRQF_ONESHOT
;
964 INIT_KFIFO(le
->events
);
965 init_waitqueue_head(&le
->wait
);
966 mutex_init(&le
->read_lock
);
968 /* Request a thread to read the events */
969 ret
= request_threaded_irq(le
->irq
,
970 lineevent_irq_handler
,
971 lineevent_irq_thread
,
978 fd
= get_unused_fd_flags(O_RDONLY
| O_CLOEXEC
);
984 file
= anon_inode_getfile("gpio-event",
987 O_RDONLY
| O_CLOEXEC
);
990 goto out_put_unused_fd
;
994 if (copy_to_user(ip
, &eventreq
, sizeof(eventreq
))) {
996 * fput() will trigger the release() callback, so do not go onto
997 * the regular error cleanup path here.
1004 fd_install(fd
, file
);
1011 free_irq(le
->irq
, le
);
1013 gpiod_free(le
->desc
);
1018 put_device(&gdev
->dev
);
1023 * gpio_ioctl() - ioctl handler for the GPIO chardev
1025 static long gpio_ioctl(struct file
*filp
, unsigned int cmd
, unsigned long arg
)
1027 struct gpio_device
*gdev
= filp
->private_data
;
1028 struct gpio_chip
*chip
= gdev
->chip
;
1029 void __user
*ip
= (void __user
*)arg
;
1031 /* We fail any subsequent ioctl():s when the chip is gone */
1035 /* Fill in the struct and pass to userspace */
1036 if (cmd
== GPIO_GET_CHIPINFO_IOCTL
) {
1037 struct gpiochip_info chipinfo
;
1039 memset(&chipinfo
, 0, sizeof(chipinfo
));
1041 strncpy(chipinfo
.name
, dev_name(&gdev
->dev
),
1042 sizeof(chipinfo
.name
));
1043 chipinfo
.name
[sizeof(chipinfo
.name
)-1] = '\0';
1044 strncpy(chipinfo
.label
, gdev
->label
,
1045 sizeof(chipinfo
.label
));
1046 chipinfo
.label
[sizeof(chipinfo
.label
)-1] = '\0';
1047 chipinfo
.lines
= gdev
->ngpio
;
1048 if (copy_to_user(ip
, &chipinfo
, sizeof(chipinfo
)))
1051 } else if (cmd
== GPIO_GET_LINEINFO_IOCTL
) {
1052 struct gpioline_info lineinfo
;
1053 struct gpio_desc
*desc
;
1055 if (copy_from_user(&lineinfo
, ip
, sizeof(lineinfo
)))
1057 if (lineinfo
.line_offset
>= gdev
->ngpio
)
1060 desc
= &gdev
->descs
[lineinfo
.line_offset
];
1062 strncpy(lineinfo
.name
, desc
->name
,
1063 sizeof(lineinfo
.name
));
1064 lineinfo
.name
[sizeof(lineinfo
.name
)-1] = '\0';
1066 lineinfo
.name
[0] = '\0';
1069 strncpy(lineinfo
.consumer
, desc
->label
,
1070 sizeof(lineinfo
.consumer
));
1071 lineinfo
.consumer
[sizeof(lineinfo
.consumer
)-1] = '\0';
1073 lineinfo
.consumer
[0] = '\0';
1077 * Userspace only need to know that the kernel is using
1078 * this GPIO so it can't use it.
1081 if (test_bit(FLAG_REQUESTED
, &desc
->flags
) ||
1082 test_bit(FLAG_IS_HOGGED
, &desc
->flags
) ||
1083 test_bit(FLAG_USED_AS_IRQ
, &desc
->flags
) ||
1084 test_bit(FLAG_EXPORT
, &desc
->flags
) ||
1085 test_bit(FLAG_SYSFS
, &desc
->flags
))
1086 lineinfo
.flags
|= GPIOLINE_FLAG_KERNEL
;
1087 if (test_bit(FLAG_IS_OUT
, &desc
->flags
))
1088 lineinfo
.flags
|= GPIOLINE_FLAG_IS_OUT
;
1089 if (test_bit(FLAG_ACTIVE_LOW
, &desc
->flags
))
1090 lineinfo
.flags
|= GPIOLINE_FLAG_ACTIVE_LOW
;
1091 if (test_bit(FLAG_OPEN_DRAIN
, &desc
->flags
))
1092 lineinfo
.flags
|= GPIOLINE_FLAG_OPEN_DRAIN
;
1093 if (test_bit(FLAG_OPEN_SOURCE
, &desc
->flags
))
1094 lineinfo
.flags
|= GPIOLINE_FLAG_OPEN_SOURCE
;
1096 if (copy_to_user(ip
, &lineinfo
, sizeof(lineinfo
)))
1099 } else if (cmd
== GPIO_GET_LINEHANDLE_IOCTL
) {
1100 return linehandle_create(gdev
, ip
);
1101 } else if (cmd
== GPIO_GET_LINEEVENT_IOCTL
) {
1102 return lineevent_create(gdev
, ip
);
1107 #ifdef CONFIG_COMPAT
1108 static long gpio_ioctl_compat(struct file
*filp
, unsigned int cmd
,
1111 return gpio_ioctl(filp
, cmd
, (unsigned long)compat_ptr(arg
));
1116 * gpio_chrdev_open() - open the chardev for ioctl operations
1117 * @inode: inode for this chardev
1118 * @filp: file struct for storing private data
1119 * Returns 0 on success
1121 static int gpio_chrdev_open(struct inode
*inode
, struct file
*filp
)
1123 struct gpio_device
*gdev
= container_of(inode
->i_cdev
,
1124 struct gpio_device
, chrdev
);
1126 /* Fail on open if the backing gpiochip is gone */
1129 get_device(&gdev
->dev
);
1130 filp
->private_data
= gdev
;
1132 return nonseekable_open(inode
, filp
);
1136 * gpio_chrdev_release() - close chardev after ioctl operations
1137 * @inode: inode for this chardev
1138 * @filp: file struct for storing private data
1139 * Returns 0 on success
1141 static int gpio_chrdev_release(struct inode
*inode
, struct file
*filp
)
1143 struct gpio_device
*gdev
= container_of(inode
->i_cdev
,
1144 struct gpio_device
, chrdev
);
1146 put_device(&gdev
->dev
);
1151 static const struct file_operations gpio_fileops
= {
1152 .release
= gpio_chrdev_release
,
1153 .open
= gpio_chrdev_open
,
1154 .owner
= THIS_MODULE
,
1155 .llseek
= no_llseek
,
1156 .unlocked_ioctl
= gpio_ioctl
,
1157 #ifdef CONFIG_COMPAT
1158 .compat_ioctl
= gpio_ioctl_compat
,
1162 static void gpiodevice_release(struct device
*dev
)
1164 struct gpio_device
*gdev
= dev_get_drvdata(dev
);
1166 list_del(&gdev
->list
);
1167 ida_simple_remove(&gpio_ida
, gdev
->id
);
1168 kfree_const(gdev
->label
);
1173 static int gpiochip_setup_dev(struct gpio_device
*gdev
)
1177 cdev_init(&gdev
->chrdev
, &gpio_fileops
);
1178 gdev
->chrdev
.owner
= THIS_MODULE
;
1179 gdev
->dev
.devt
= MKDEV(MAJOR(gpio_devt
), gdev
->id
);
1181 status
= cdev_device_add(&gdev
->chrdev
, &gdev
->dev
);
1185 chip_dbg(gdev
->chip
, "added GPIO chardev (%d:%d)\n",
1186 MAJOR(gpio_devt
), gdev
->id
);
1188 status
= gpiochip_sysfs_register(gdev
);
1190 goto err_remove_device
;
1192 /* From this point, the .release() function cleans up gpio_device */
1193 gdev
->dev
.release
= gpiodevice_release
;
1194 pr_debug("%s: registered GPIOs %d to %d on device: %s (%s)\n",
1195 __func__
, gdev
->base
, gdev
->base
+ gdev
->ngpio
- 1,
1196 dev_name(&gdev
->dev
), gdev
->chip
->label
? : "generic");
1201 cdev_device_del(&gdev
->chrdev
, &gdev
->dev
);
1205 static void gpiochip_machine_hog(struct gpio_chip
*chip
, struct gpiod_hog
*hog
)
1207 struct gpio_desc
*desc
;
1210 desc
= gpiochip_get_desc(chip
, hog
->chip_hwnum
);
1212 pr_err("%s: unable to get GPIO desc: %ld\n",
1213 __func__
, PTR_ERR(desc
));
1217 if (test_bit(FLAG_IS_HOGGED
, &desc
->flags
))
1220 rv
= gpiod_hog(desc
, hog
->line_name
, hog
->lflags
, hog
->dflags
);
1222 pr_err("%s: unable to hog GPIO line (%s:%u): %d\n",
1223 __func__
, chip
->label
, hog
->chip_hwnum
, rv
);
1226 static void machine_gpiochip_add(struct gpio_chip
*chip
)
1228 struct gpiod_hog
*hog
;
1230 mutex_lock(&gpio_machine_hogs_mutex
);
1232 list_for_each_entry(hog
, &gpio_machine_hogs
, list
) {
1233 if (!strcmp(chip
->label
, hog
->chip_label
))
1234 gpiochip_machine_hog(chip
, hog
);
1237 mutex_unlock(&gpio_machine_hogs_mutex
);
1240 static void gpiochip_setup_devs(void)
1242 struct gpio_device
*gdev
;
1245 list_for_each_entry(gdev
, &gpio_devices
, list
) {
1246 err
= gpiochip_setup_dev(gdev
);
1248 pr_err("%s: Failed to initialize gpio device (%d)\n",
1249 dev_name(&gdev
->dev
), err
);
1253 int gpiochip_add_data_with_key(struct gpio_chip
*chip
, void *data
,
1254 struct lock_class_key
*lock_key
,
1255 struct lock_class_key
*request_key
)
1257 unsigned long flags
;
1260 int base
= chip
->base
;
1261 struct gpio_device
*gdev
;
1264 * First: allocate and populate the internal stat container, and
1265 * set up the struct device.
1267 gdev
= kzalloc(sizeof(*gdev
), GFP_KERNEL
);
1270 gdev
->dev
.bus
= &gpio_bus_type
;
1272 chip
->gpiodev
= gdev
;
1274 gdev
->dev
.parent
= chip
->parent
;
1275 gdev
->dev
.of_node
= chip
->parent
->of_node
;
1278 #ifdef CONFIG_OF_GPIO
1279 /* If the gpiochip has an assigned OF node this takes precedence */
1281 gdev
->dev
.of_node
= chip
->of_node
;
1283 chip
->of_node
= gdev
->dev
.of_node
;
1286 gdev
->id
= ida_simple_get(&gpio_ida
, 0, 0, GFP_KERNEL
);
1291 dev_set_name(&gdev
->dev
, "gpiochip%d", gdev
->id
);
1292 device_initialize(&gdev
->dev
);
1293 dev_set_drvdata(&gdev
->dev
, gdev
);
1294 if (chip
->parent
&& chip
->parent
->driver
)
1295 gdev
->owner
= chip
->parent
->driver
->owner
;
1296 else if (chip
->owner
)
1297 /* TODO: remove chip->owner */
1298 gdev
->owner
= chip
->owner
;
1300 gdev
->owner
= THIS_MODULE
;
1302 gdev
->descs
= kcalloc(chip
->ngpio
, sizeof(gdev
->descs
[0]), GFP_KERNEL
);
1308 if (chip
->ngpio
== 0) {
1309 chip_err(chip
, "tried to insert a GPIO chip with zero lines\n");
1311 goto err_free_descs
;
1314 if (chip
->ngpio
> FASTPATH_NGPIO
)
1315 chip_warn(chip
, "line cnt %u is greater than fast path cnt %u\n",
1316 chip
->ngpio
, FASTPATH_NGPIO
);
1318 gdev
->label
= kstrdup_const(chip
->label
?: "unknown", GFP_KERNEL
);
1321 goto err_free_descs
;
1324 gdev
->ngpio
= chip
->ngpio
;
1327 spin_lock_irqsave(&gpio_lock
, flags
);
1330 * TODO: this allocates a Linux GPIO number base in the global
1331 * GPIO numberspace for this chip. In the long run we want to
1332 * get *rid* of this numberspace and use only descriptors, but
1333 * it may be a pipe dream. It will not happen before we get rid
1334 * of the sysfs interface anyways.
1337 base
= gpiochip_find_base(chip
->ngpio
);
1340 spin_unlock_irqrestore(&gpio_lock
, flags
);
1341 goto err_free_label
;
1344 * TODO: it should not be necessary to reflect the assigned
1345 * base outside of the GPIO subsystem. Go over drivers and
1346 * see if anyone makes use of this, else drop this and assign
1353 status
= gpiodev_add_to_list(gdev
);
1355 spin_unlock_irqrestore(&gpio_lock
, flags
);
1356 goto err_free_label
;
1359 spin_unlock_irqrestore(&gpio_lock
, flags
);
1361 for (i
= 0; i
< chip
->ngpio
; i
++)
1362 gdev
->descs
[i
].gdev
= gdev
;
1364 #ifdef CONFIG_PINCTRL
1365 INIT_LIST_HEAD(&gdev
->pin_ranges
);
1368 status
= gpiochip_set_desc_names(chip
);
1370 goto err_remove_from_list
;
1372 status
= gpiochip_irqchip_init_valid_mask(chip
);
1374 goto err_remove_from_list
;
1376 status
= gpiochip_alloc_valid_mask(chip
);
1378 goto err_remove_irqchip_mask
;
1380 status
= gpiochip_add_irqchip(chip
, lock_key
, request_key
);
1382 goto err_remove_chip
;
1384 status
= of_gpiochip_add(chip
);
1386 goto err_remove_chip
;
1388 status
= gpiochip_init_valid_mask(chip
);
1390 goto err_remove_chip
;
1392 for (i
= 0; i
< chip
->ngpio
; i
++) {
1393 struct gpio_desc
*desc
= &gdev
->descs
[i
];
1395 if (chip
->get_direction
&& gpiochip_line_is_valid(chip
, i
))
1396 desc
->flags
= !chip
->get_direction(chip
, i
) ?
1397 (1 << FLAG_IS_OUT
) : 0;
1399 desc
->flags
= !chip
->direction_input
?
1400 (1 << FLAG_IS_OUT
) : 0;
1403 acpi_gpiochip_add(chip
);
1405 machine_gpiochip_add(chip
);
1408 * By first adding the chardev, and then adding the device,
1409 * we get a device node entry in sysfs under
1410 * /sys/bus/gpio/devices/gpiochipN/dev that can be used for
1411 * coldplug of device nodes and other udev business.
1412 * We can do this only if gpiolib has been initialized.
1413 * Otherwise, defer until later.
1415 if (gpiolib_initialized
) {
1416 status
= gpiochip_setup_dev(gdev
);
1418 goto err_remove_chip
;
1423 acpi_gpiochip_remove(chip
);
1424 gpiochip_free_hogs(chip
);
1425 of_gpiochip_remove(chip
);
1426 gpiochip_free_valid_mask(chip
);
1427 err_remove_irqchip_mask
:
1428 gpiochip_irqchip_free_valid_mask(chip
);
1429 err_remove_from_list
:
1430 spin_lock_irqsave(&gpio_lock
, flags
);
1431 list_del(&gdev
->list
);
1432 spin_unlock_irqrestore(&gpio_lock
, flags
);
1434 kfree_const(gdev
->label
);
1438 ida_simple_remove(&gpio_ida
, gdev
->id
);
1440 /* failures here can mean systems won't boot... */
1441 pr_err("%s: GPIOs %d..%d (%s) failed to register, %d\n", __func__
,
1442 gdev
->base
, gdev
->base
+ gdev
->ngpio
- 1,
1443 chip
->label
? : "generic", status
);
1447 EXPORT_SYMBOL_GPL(gpiochip_add_data_with_key
);
1450 * gpiochip_get_data() - get per-subdriver data for the chip
1454 * The per-subdriver data for the chip.
1456 void *gpiochip_get_data(struct gpio_chip
*chip
)
1458 return chip
->gpiodev
->data
;
1460 EXPORT_SYMBOL_GPL(gpiochip_get_data
);
1463 * gpiochip_remove() - unregister a gpio_chip
1464 * @chip: the chip to unregister
1466 * A gpio_chip with any GPIOs still requested may not be removed.
1468 void gpiochip_remove(struct gpio_chip
*chip
)
1470 struct gpio_device
*gdev
= chip
->gpiodev
;
1471 struct gpio_desc
*desc
;
1472 unsigned long flags
;
1474 bool requested
= false;
1476 /* FIXME: should the legacy sysfs handling be moved to gpio_device? */
1477 gpiochip_sysfs_unregister(gdev
);
1478 gpiochip_free_hogs(chip
);
1479 /* Numb the device, cancelling all outstanding operations */
1481 gpiochip_irqchip_remove(chip
);
1482 acpi_gpiochip_remove(chip
);
1483 gpiochip_remove_pin_ranges(chip
);
1484 of_gpiochip_remove(chip
);
1485 gpiochip_free_valid_mask(chip
);
1487 * We accept no more calls into the driver from this point, so
1488 * NULL the driver data pointer
1492 spin_lock_irqsave(&gpio_lock
, flags
);
1493 for (i
= 0; i
< gdev
->ngpio
; i
++) {
1494 desc
= &gdev
->descs
[i
];
1495 if (test_bit(FLAG_REQUESTED
, &desc
->flags
))
1498 spin_unlock_irqrestore(&gpio_lock
, flags
);
1501 dev_crit(&gdev
->dev
,
1502 "REMOVING GPIOCHIP WITH GPIOS STILL REQUESTED\n");
1505 * The gpiochip side puts its use of the device to rest here:
1506 * if there are no userspace clients, the chardev and device will
1507 * be removed, else it will be dangling until the last user is
1510 cdev_device_del(&gdev
->chrdev
, &gdev
->dev
);
1511 put_device(&gdev
->dev
);
1513 EXPORT_SYMBOL_GPL(gpiochip_remove
);
1515 static void devm_gpio_chip_release(struct device
*dev
, void *res
)
1517 struct gpio_chip
*chip
= *(struct gpio_chip
**)res
;
1519 gpiochip_remove(chip
);
1523 * devm_gpiochip_add_data() - Resource manager gpiochip_add_data()
1524 * @dev: pointer to the device that gpio_chip belongs to.
1525 * @chip: the chip to register, with chip->base initialized
1526 * @data: driver-private data associated with this chip
1528 * Context: potentially before irqs will work
1530 * The gpio chip automatically be released when the device is unbound.
1533 * A negative errno if the chip can't be registered, such as because the
1534 * chip->base is invalid or already associated with a different chip.
1535 * Otherwise it returns zero as a success code.
1537 int devm_gpiochip_add_data(struct device
*dev
, struct gpio_chip
*chip
,
1540 struct gpio_chip
**ptr
;
1543 ptr
= devres_alloc(devm_gpio_chip_release
, sizeof(*ptr
),
1548 ret
= gpiochip_add_data(chip
, data
);
1555 devres_add(dev
, ptr
);
1559 EXPORT_SYMBOL_GPL(devm_gpiochip_add_data
);
1562 * gpiochip_find() - iterator for locating a specific gpio_chip
1563 * @data: data to pass to match function
1564 * @match: Callback function to check gpio_chip
1566 * Similar to bus_find_device. It returns a reference to a gpio_chip as
1567 * determined by a user supplied @match callback. The callback should return
1568 * 0 if the device doesn't match and non-zero if it does. If the callback is
1569 * non-zero, this function will return to the caller and not iterate over any
1572 struct gpio_chip
*gpiochip_find(void *data
,
1573 int (*match
)(struct gpio_chip
*chip
,
1576 struct gpio_device
*gdev
;
1577 struct gpio_chip
*chip
= NULL
;
1578 unsigned long flags
;
1580 spin_lock_irqsave(&gpio_lock
, flags
);
1581 list_for_each_entry(gdev
, &gpio_devices
, list
)
1582 if (gdev
->chip
&& match(gdev
->chip
, data
)) {
1587 spin_unlock_irqrestore(&gpio_lock
, flags
);
1591 EXPORT_SYMBOL_GPL(gpiochip_find
);
1593 static int gpiochip_match_name(struct gpio_chip
*chip
, void *data
)
1595 const char *name
= data
;
1597 return !strcmp(chip
->label
, name
);
1600 static struct gpio_chip
*find_chip_by_name(const char *name
)
1602 return gpiochip_find((void *)name
, gpiochip_match_name
);
1605 #ifdef CONFIG_GPIOLIB_IRQCHIP
1608 * The following is irqchip helper code for gpiochips.
1611 static int gpiochip_irqchip_init_valid_mask(struct gpio_chip
*gpiochip
)
1613 if (!gpiochip
->irq
.need_valid_mask
)
1616 gpiochip
->irq
.valid_mask
= gpiochip_allocate_mask(gpiochip
);
1617 if (!gpiochip
->irq
.valid_mask
)
1623 static void gpiochip_irqchip_free_valid_mask(struct gpio_chip
*gpiochip
)
1625 kfree(gpiochip
->irq
.valid_mask
);
1626 gpiochip
->irq
.valid_mask
= NULL
;
1629 bool gpiochip_irqchip_irq_valid(const struct gpio_chip
*gpiochip
,
1630 unsigned int offset
)
1632 if (!gpiochip_line_is_valid(gpiochip
, offset
))
1634 /* No mask means all valid */
1635 if (likely(!gpiochip
->irq
.valid_mask
))
1637 return test_bit(offset
, gpiochip
->irq
.valid_mask
);
1639 EXPORT_SYMBOL_GPL(gpiochip_irqchip_irq_valid
);
1642 * gpiochip_set_cascaded_irqchip() - connects a cascaded irqchip to a gpiochip
1643 * @gpiochip: the gpiochip to set the irqchip chain to
1644 * @parent_irq: the irq number corresponding to the parent IRQ for this
1646 * @parent_handler: the parent interrupt handler for the accumulated IRQ
1647 * coming out of the gpiochip. If the interrupt is nested rather than
1648 * cascaded, pass NULL in this handler argument
1650 static void gpiochip_set_cascaded_irqchip(struct gpio_chip
*gpiochip
,
1651 unsigned int parent_irq
,
1652 irq_flow_handler_t parent_handler
)
1654 if (!gpiochip
->irq
.domain
) {
1655 chip_err(gpiochip
, "called %s before setting up irqchip\n",
1660 if (parent_handler
) {
1661 if (gpiochip
->can_sleep
) {
1663 "you cannot have chained interrupts on a chip that may sleep\n");
1667 * The parent irqchip is already using the chip_data for this
1668 * irqchip, so our callbacks simply use the handler_data.
1670 irq_set_chained_handler_and_data(parent_irq
, parent_handler
,
1673 gpiochip
->irq
.parent_irq
= parent_irq
;
1674 gpiochip
->irq
.parents
= &gpiochip
->irq
.parent_irq
;
1675 gpiochip
->irq
.num_parents
= 1;
1680 * gpiochip_set_chained_irqchip() - connects a chained irqchip to a gpiochip
1681 * @gpiochip: the gpiochip to set the irqchip chain to
1682 * @irqchip: the irqchip to chain to the gpiochip
1683 * @parent_irq: the irq number corresponding to the parent IRQ for this
1685 * @parent_handler: the parent interrupt handler for the accumulated IRQ
1686 * coming out of the gpiochip.
1688 void gpiochip_set_chained_irqchip(struct gpio_chip
*gpiochip
,
1689 struct irq_chip
*irqchip
,
1690 unsigned int parent_irq
,
1691 irq_flow_handler_t parent_handler
)
1693 if (gpiochip
->irq
.threaded
) {
1694 chip_err(gpiochip
, "tried to chain a threaded gpiochip\n");
1698 gpiochip_set_cascaded_irqchip(gpiochip
, parent_irq
, parent_handler
);
1700 EXPORT_SYMBOL_GPL(gpiochip_set_chained_irqchip
);
1703 * gpiochip_set_nested_irqchip() - connects a nested irqchip to a gpiochip
1704 * @gpiochip: the gpiochip to set the irqchip nested handler to
1705 * @irqchip: the irqchip to nest to the gpiochip
1706 * @parent_irq: the irq number corresponding to the parent IRQ for this
1709 void gpiochip_set_nested_irqchip(struct gpio_chip
*gpiochip
,
1710 struct irq_chip
*irqchip
,
1711 unsigned int parent_irq
)
1713 gpiochip_set_cascaded_irqchip(gpiochip
, parent_irq
, NULL
);
1715 EXPORT_SYMBOL_GPL(gpiochip_set_nested_irqchip
);
1718 * gpiochip_irq_map() - maps an IRQ into a GPIO irqchip
1719 * @d: the irqdomain used by this irqchip
1720 * @irq: the global irq number used by this GPIO irqchip irq
1721 * @hwirq: the local IRQ/GPIO line offset on this gpiochip
1723 * This function will set up the mapping for a certain IRQ line on a
1724 * gpiochip by assigning the gpiochip as chip data, and using the irqchip
1725 * stored inside the gpiochip.
1727 int gpiochip_irq_map(struct irq_domain
*d
, unsigned int irq
,
1728 irq_hw_number_t hwirq
)
1730 struct gpio_chip
*chip
= d
->host_data
;
1733 if (!gpiochip_irqchip_irq_valid(chip
, hwirq
))
1736 irq_set_chip_data(irq
, chip
);
1738 * This lock class tells lockdep that GPIO irqs are in a different
1739 * category than their parents, so it won't report false recursion.
1741 irq_set_lockdep_class(irq
, chip
->irq
.lock_key
, chip
->irq
.request_key
);
1742 irq_set_chip_and_handler(irq
, chip
->irq
.chip
, chip
->irq
.handler
);
1743 /* Chips that use nested thread handlers have them marked */
1744 if (chip
->irq
.threaded
)
1745 irq_set_nested_thread(irq
, 1);
1746 irq_set_noprobe(irq
);
1748 if (chip
->irq
.num_parents
== 1)
1749 err
= irq_set_parent(irq
, chip
->irq
.parents
[0]);
1750 else if (chip
->irq
.map
)
1751 err
= irq_set_parent(irq
, chip
->irq
.map
[hwirq
]);
1757 * No set-up of the hardware will happen if IRQ_TYPE_NONE
1758 * is passed as default type.
1760 if (chip
->irq
.default_type
!= IRQ_TYPE_NONE
)
1761 irq_set_irq_type(irq
, chip
->irq
.default_type
);
1765 EXPORT_SYMBOL_GPL(gpiochip_irq_map
);
1767 void gpiochip_irq_unmap(struct irq_domain
*d
, unsigned int irq
)
1769 struct gpio_chip
*chip
= d
->host_data
;
1771 if (chip
->irq
.threaded
)
1772 irq_set_nested_thread(irq
, 0);
1773 irq_set_chip_and_handler(irq
, NULL
, NULL
);
1774 irq_set_chip_data(irq
, NULL
);
1776 EXPORT_SYMBOL_GPL(gpiochip_irq_unmap
);
1778 static const struct irq_domain_ops gpiochip_domain_ops
= {
1779 .map
= gpiochip_irq_map
,
1780 .unmap
= gpiochip_irq_unmap
,
1781 /* Virtually all GPIO irqchips are twocell:ed */
1782 .xlate
= irq_domain_xlate_twocell
,
1785 static int gpiochip_to_irq(struct gpio_chip
*chip
, unsigned offset
)
1787 if (!gpiochip_irqchip_irq_valid(chip
, offset
))
1790 return irq_create_mapping(chip
->irq
.domain
, offset
);
1793 static int gpiochip_irq_reqres(struct irq_data
*d
)
1795 struct gpio_chip
*chip
= irq_data_get_irq_chip_data(d
);
1797 return gpiochip_reqres_irq(chip
, d
->hwirq
);
1800 static void gpiochip_irq_relres(struct irq_data
*d
)
1802 struct gpio_chip
*chip
= irq_data_get_irq_chip_data(d
);
1804 gpiochip_relres_irq(chip
, d
->hwirq
);
1807 static void gpiochip_irq_enable(struct irq_data
*d
)
1809 struct gpio_chip
*chip
= irq_data_get_irq_chip_data(d
);
1811 gpiochip_enable_irq(chip
, d
->hwirq
);
1812 if (chip
->irq
.irq_enable
)
1813 chip
->irq
.irq_enable(d
);
1815 chip
->irq
.chip
->irq_unmask(d
);
1818 static void gpiochip_irq_disable(struct irq_data
*d
)
1820 struct gpio_chip
*chip
= irq_data_get_irq_chip_data(d
);
1822 if (chip
->irq
.irq_disable
)
1823 chip
->irq
.irq_disable(d
);
1825 chip
->irq
.chip
->irq_mask(d
);
1826 gpiochip_disable_irq(chip
, d
->hwirq
);
1829 static void gpiochip_set_irq_hooks(struct gpio_chip
*gpiochip
)
1831 struct irq_chip
*irqchip
= gpiochip
->irq
.chip
;
1833 if (!irqchip
->irq_request_resources
&&
1834 !irqchip
->irq_release_resources
) {
1835 irqchip
->irq_request_resources
= gpiochip_irq_reqres
;
1836 irqchip
->irq_release_resources
= gpiochip_irq_relres
;
1838 if (WARN_ON(gpiochip
->irq
.irq_enable
))
1840 /* Check if the irqchip already has this hook... */
1841 if (irqchip
->irq_enable
== gpiochip_irq_enable
) {
1843 * ...and if so, give a gentle warning that this is bad
1847 "detected irqchip that is shared with multiple gpiochips: please fix the driver.\n");
1850 gpiochip
->irq
.irq_enable
= irqchip
->irq_enable
;
1851 gpiochip
->irq
.irq_disable
= irqchip
->irq_disable
;
1852 irqchip
->irq_enable
= gpiochip_irq_enable
;
1853 irqchip
->irq_disable
= gpiochip_irq_disable
;
1857 * gpiochip_add_irqchip() - adds an IRQ chip to a GPIO chip
1858 * @gpiochip: the GPIO chip to add the IRQ chip to
1859 * @lock_key: lockdep class for IRQ lock
1860 * @request_key: lockdep class for IRQ request
1862 static int gpiochip_add_irqchip(struct gpio_chip
*gpiochip
,
1863 struct lock_class_key
*lock_key
,
1864 struct lock_class_key
*request_key
)
1866 struct irq_chip
*irqchip
= gpiochip
->irq
.chip
;
1867 const struct irq_domain_ops
*ops
;
1868 struct device_node
*np
;
1875 if (gpiochip
->irq
.parent_handler
&& gpiochip
->can_sleep
) {
1876 chip_err(gpiochip
, "you cannot have chained interrupts on a chip that may sleep\n");
1880 np
= gpiochip
->gpiodev
->dev
.of_node
;
1881 type
= gpiochip
->irq
.default_type
;
1884 * Specifying a default trigger is a terrible idea if DT or ACPI is
1885 * used to configure the interrupts, as you may end up with
1886 * conflicting triggers. Tell the user, and reset to NONE.
1888 if (WARN(np
&& type
!= IRQ_TYPE_NONE
,
1889 "%s: Ignoring %u default trigger\n", np
->full_name
, type
))
1890 type
= IRQ_TYPE_NONE
;
1892 if (has_acpi_companion(gpiochip
->parent
) && type
!= IRQ_TYPE_NONE
) {
1893 acpi_handle_warn(ACPI_HANDLE(gpiochip
->parent
),
1894 "Ignoring %u default trigger\n", type
);
1895 type
= IRQ_TYPE_NONE
;
1898 gpiochip
->to_irq
= gpiochip_to_irq
;
1899 gpiochip
->irq
.default_type
= type
;
1900 gpiochip
->irq
.lock_key
= lock_key
;
1901 gpiochip
->irq
.request_key
= request_key
;
1903 if (gpiochip
->irq
.domain_ops
)
1904 ops
= gpiochip
->irq
.domain_ops
;
1906 ops
= &gpiochip_domain_ops
;
1908 gpiochip
->irq
.domain
= irq_domain_add_simple(np
, gpiochip
->ngpio
,
1909 gpiochip
->irq
.first
,
1911 if (!gpiochip
->irq
.domain
)
1914 if (gpiochip
->irq
.parent_handler
) {
1915 void *data
= gpiochip
->irq
.parent_handler_data
?: gpiochip
;
1917 for (i
= 0; i
< gpiochip
->irq
.num_parents
; i
++) {
1919 * The parent IRQ chip is already using the chip_data
1920 * for this IRQ chip, so our callbacks simply use the
1923 irq_set_chained_handler_and_data(gpiochip
->irq
.parents
[i
],
1924 gpiochip
->irq
.parent_handler
,
1929 gpiochip_set_irq_hooks(gpiochip
);
1931 acpi_gpiochip_request_interrupts(gpiochip
);
1937 * gpiochip_irqchip_remove() - removes an irqchip added to a gpiochip
1938 * @gpiochip: the gpiochip to remove the irqchip from
1940 * This is called only from gpiochip_remove()
1942 static void gpiochip_irqchip_remove(struct gpio_chip
*gpiochip
)
1944 struct irq_chip
*irqchip
= gpiochip
->irq
.chip
;
1945 unsigned int offset
;
1947 acpi_gpiochip_free_interrupts(gpiochip
);
1949 if (irqchip
&& gpiochip
->irq
.parent_handler
) {
1950 struct gpio_irq_chip
*irq
= &gpiochip
->irq
;
1953 for (i
= 0; i
< irq
->num_parents
; i
++)
1954 irq_set_chained_handler_and_data(irq
->parents
[i
],
1958 /* Remove all IRQ mappings and delete the domain */
1959 if (gpiochip
->irq
.domain
) {
1962 for (offset
= 0; offset
< gpiochip
->ngpio
; offset
++) {
1963 if (!gpiochip_irqchip_irq_valid(gpiochip
, offset
))
1966 irq
= irq_find_mapping(gpiochip
->irq
.domain
, offset
);
1967 irq_dispose_mapping(irq
);
1970 irq_domain_remove(gpiochip
->irq
.domain
);
1974 if (irqchip
->irq_request_resources
== gpiochip_irq_reqres
) {
1975 irqchip
->irq_request_resources
= NULL
;
1976 irqchip
->irq_release_resources
= NULL
;
1978 if (irqchip
->irq_enable
== gpiochip_irq_enable
) {
1979 irqchip
->irq_enable
= gpiochip
->irq
.irq_enable
;
1980 irqchip
->irq_disable
= gpiochip
->irq
.irq_disable
;
1983 gpiochip
->irq
.irq_enable
= NULL
;
1984 gpiochip
->irq
.irq_disable
= NULL
;
1985 gpiochip
->irq
.chip
= NULL
;
1987 gpiochip_irqchip_free_valid_mask(gpiochip
);
1991 * gpiochip_irqchip_add_key() - adds an irqchip to a gpiochip
1992 * @gpiochip: the gpiochip to add the irqchip to
1993 * @irqchip: the irqchip to add to the gpiochip
1994 * @first_irq: if not dynamically assigned, the base (first) IRQ to
1995 * allocate gpiochip irqs from
1996 * @handler: the irq handler to use (often a predefined irq core function)
1997 * @type: the default type for IRQs on this irqchip, pass IRQ_TYPE_NONE
1998 * to have the core avoid setting up any default type in the hardware.
1999 * @threaded: whether this irqchip uses a nested thread handler
2000 * @lock_key: lockdep class for IRQ lock
2001 * @request_key: lockdep class for IRQ request
2003 * This function closely associates a certain irqchip with a certain
2004 * gpiochip, providing an irq domain to translate the local IRQs to
2005 * global irqs in the gpiolib core, and making sure that the gpiochip
2006 * is passed as chip data to all related functions. Driver callbacks
2007 * need to use gpiochip_get_data() to get their local state containers back
2008 * from the gpiochip passed as chip data. An irqdomain will be stored
2009 * in the gpiochip that shall be used by the driver to handle IRQ number
2010 * translation. The gpiochip will need to be initialized and registered
2011 * before calling this function.
2013 * This function will handle two cell:ed simple IRQs and assumes all
2014 * the pins on the gpiochip can generate a unique IRQ. Everything else
2015 * need to be open coded.
2017 int gpiochip_irqchip_add_key(struct gpio_chip
*gpiochip
,
2018 struct irq_chip
*irqchip
,
2019 unsigned int first_irq
,
2020 irq_flow_handler_t handler
,
2023 struct lock_class_key
*lock_key
,
2024 struct lock_class_key
*request_key
)
2026 struct device_node
*of_node
;
2028 if (!gpiochip
|| !irqchip
)
2031 if (!gpiochip
->parent
) {
2032 pr_err("missing gpiochip .dev parent pointer\n");
2035 gpiochip
->irq
.threaded
= threaded
;
2036 of_node
= gpiochip
->parent
->of_node
;
2037 #ifdef CONFIG_OF_GPIO
2039 * If the gpiochip has an assigned OF node this takes precedence
2040 * FIXME: get rid of this and use gpiochip->parent->of_node
2043 if (gpiochip
->of_node
)
2044 of_node
= gpiochip
->of_node
;
2047 * Specifying a default trigger is a terrible idea if DT or ACPI is
2048 * used to configure the interrupts, as you may end-up with
2049 * conflicting triggers. Tell the user, and reset to NONE.
2051 if (WARN(of_node
&& type
!= IRQ_TYPE_NONE
,
2052 "%pOF: Ignoring %d default trigger\n", of_node
, type
))
2053 type
= IRQ_TYPE_NONE
;
2054 if (has_acpi_companion(gpiochip
->parent
) && type
!= IRQ_TYPE_NONE
) {
2055 acpi_handle_warn(ACPI_HANDLE(gpiochip
->parent
),
2056 "Ignoring %d default trigger\n", type
);
2057 type
= IRQ_TYPE_NONE
;
2060 gpiochip
->irq
.chip
= irqchip
;
2061 gpiochip
->irq
.handler
= handler
;
2062 gpiochip
->irq
.default_type
= type
;
2063 gpiochip
->to_irq
= gpiochip_to_irq
;
2064 gpiochip
->irq
.lock_key
= lock_key
;
2065 gpiochip
->irq
.request_key
= request_key
;
2066 gpiochip
->irq
.domain
= irq_domain_add_simple(of_node
,
2067 gpiochip
->ngpio
, first_irq
,
2068 &gpiochip_domain_ops
, gpiochip
);
2069 if (!gpiochip
->irq
.domain
) {
2070 gpiochip
->irq
.chip
= NULL
;
2074 gpiochip_set_irq_hooks(gpiochip
);
2076 acpi_gpiochip_request_interrupts(gpiochip
);
2080 EXPORT_SYMBOL_GPL(gpiochip_irqchip_add_key
);
2082 #else /* CONFIG_GPIOLIB_IRQCHIP */
2084 static inline int gpiochip_add_irqchip(struct gpio_chip
*gpiochip
,
2085 struct lock_class_key
*lock_key
,
2086 struct lock_class_key
*request_key
)
2091 static void gpiochip_irqchip_remove(struct gpio_chip
*gpiochip
) {}
2092 static inline int gpiochip_irqchip_init_valid_mask(struct gpio_chip
*gpiochip
)
2096 static inline void gpiochip_irqchip_free_valid_mask(struct gpio_chip
*gpiochip
)
2099 #endif /* CONFIG_GPIOLIB_IRQCHIP */
2102 * gpiochip_generic_request() - request the gpio function for a pin
2103 * @chip: the gpiochip owning the GPIO
2104 * @offset: the offset of the GPIO to request for GPIO function
2106 int gpiochip_generic_request(struct gpio_chip
*chip
, unsigned offset
)
2108 return pinctrl_gpio_request(chip
->gpiodev
->base
+ offset
);
2110 EXPORT_SYMBOL_GPL(gpiochip_generic_request
);
2113 * gpiochip_generic_free() - free the gpio function from a pin
2114 * @chip: the gpiochip to request the gpio function for
2115 * @offset: the offset of the GPIO to free from GPIO function
2117 void gpiochip_generic_free(struct gpio_chip
*chip
, unsigned offset
)
2119 pinctrl_gpio_free(chip
->gpiodev
->base
+ offset
);
2121 EXPORT_SYMBOL_GPL(gpiochip_generic_free
);
2124 * gpiochip_generic_config() - apply configuration for a pin
2125 * @chip: the gpiochip owning the GPIO
2126 * @offset: the offset of the GPIO to apply the configuration
2127 * @config: the configuration to be applied
2129 int gpiochip_generic_config(struct gpio_chip
*chip
, unsigned offset
,
2130 unsigned long config
)
2132 return pinctrl_gpio_set_config(chip
->gpiodev
->base
+ offset
, config
);
2134 EXPORT_SYMBOL_GPL(gpiochip_generic_config
);
2136 #ifdef CONFIG_PINCTRL
2139 * gpiochip_add_pingroup_range() - add a range for GPIO <-> pin mapping
2140 * @chip: the gpiochip to add the range for
2141 * @pctldev: the pin controller to map to
2142 * @gpio_offset: the start offset in the current gpio_chip number space
2143 * @pin_group: name of the pin group inside the pin controller
2145 * Calling this function directly from a DeviceTree-supported
2146 * pinctrl driver is DEPRECATED. Please see Section 2.1 of
2147 * Documentation/devicetree/bindings/gpio/gpio.txt on how to
2148 * bind pinctrl and gpio drivers via the "gpio-ranges" property.
2150 int gpiochip_add_pingroup_range(struct gpio_chip
*chip
,
2151 struct pinctrl_dev
*pctldev
,
2152 unsigned int gpio_offset
, const char *pin_group
)
2154 struct gpio_pin_range
*pin_range
;
2155 struct gpio_device
*gdev
= chip
->gpiodev
;
2158 pin_range
= kzalloc(sizeof(*pin_range
), GFP_KERNEL
);
2160 chip_err(chip
, "failed to allocate pin ranges\n");
2164 /* Use local offset as range ID */
2165 pin_range
->range
.id
= gpio_offset
;
2166 pin_range
->range
.gc
= chip
;
2167 pin_range
->range
.name
= chip
->label
;
2168 pin_range
->range
.base
= gdev
->base
+ gpio_offset
;
2169 pin_range
->pctldev
= pctldev
;
2171 ret
= pinctrl_get_group_pins(pctldev
, pin_group
,
2172 &pin_range
->range
.pins
,
2173 &pin_range
->range
.npins
);
2179 pinctrl_add_gpio_range(pctldev
, &pin_range
->range
);
2181 chip_dbg(chip
, "created GPIO range %d->%d ==> %s PINGRP %s\n",
2182 gpio_offset
, gpio_offset
+ pin_range
->range
.npins
- 1,
2183 pinctrl_dev_get_devname(pctldev
), pin_group
);
2185 list_add_tail(&pin_range
->node
, &gdev
->pin_ranges
);
2189 EXPORT_SYMBOL_GPL(gpiochip_add_pingroup_range
);
2192 * gpiochip_add_pin_range() - add a range for GPIO <-> pin mapping
2193 * @chip: the gpiochip to add the range for
2194 * @pinctl_name: the dev_name() of the pin controller to map to
2195 * @gpio_offset: the start offset in the current gpio_chip number space
2196 * @pin_offset: the start offset in the pin controller number space
2197 * @npins: the number of pins from the offset of each pin space (GPIO and
2198 * pin controller) to accumulate in this range
2201 * 0 on success, or a negative error-code on failure.
2203 * Calling this function directly from a DeviceTree-supported
2204 * pinctrl driver is DEPRECATED. Please see Section 2.1 of
2205 * Documentation/devicetree/bindings/gpio/gpio.txt on how to
2206 * bind pinctrl and gpio drivers via the "gpio-ranges" property.
2208 int gpiochip_add_pin_range(struct gpio_chip
*chip
, const char *pinctl_name
,
2209 unsigned int gpio_offset
, unsigned int pin_offset
,
2212 struct gpio_pin_range
*pin_range
;
2213 struct gpio_device
*gdev
= chip
->gpiodev
;
2216 pin_range
= kzalloc(sizeof(*pin_range
), GFP_KERNEL
);
2218 chip_err(chip
, "failed to allocate pin ranges\n");
2222 /* Use local offset as range ID */
2223 pin_range
->range
.id
= gpio_offset
;
2224 pin_range
->range
.gc
= chip
;
2225 pin_range
->range
.name
= chip
->label
;
2226 pin_range
->range
.base
= gdev
->base
+ gpio_offset
;
2227 pin_range
->range
.pin_base
= pin_offset
;
2228 pin_range
->range
.npins
= npins
;
2229 pin_range
->pctldev
= pinctrl_find_and_add_gpio_range(pinctl_name
,
2231 if (IS_ERR(pin_range
->pctldev
)) {
2232 ret
= PTR_ERR(pin_range
->pctldev
);
2233 chip_err(chip
, "could not create pin range\n");
2237 chip_dbg(chip
, "created GPIO range %d->%d ==> %s PIN %d->%d\n",
2238 gpio_offset
, gpio_offset
+ npins
- 1,
2240 pin_offset
, pin_offset
+ npins
- 1);
2242 list_add_tail(&pin_range
->node
, &gdev
->pin_ranges
);
2246 EXPORT_SYMBOL_GPL(gpiochip_add_pin_range
);
2249 * gpiochip_remove_pin_ranges() - remove all the GPIO <-> pin mappings
2250 * @chip: the chip to remove all the mappings for
2252 void gpiochip_remove_pin_ranges(struct gpio_chip
*chip
)
2254 struct gpio_pin_range
*pin_range
, *tmp
;
2255 struct gpio_device
*gdev
= chip
->gpiodev
;
2257 list_for_each_entry_safe(pin_range
, tmp
, &gdev
->pin_ranges
, node
) {
2258 list_del(&pin_range
->node
);
2259 pinctrl_remove_gpio_range(pin_range
->pctldev
,
2264 EXPORT_SYMBOL_GPL(gpiochip_remove_pin_ranges
);
2266 #endif /* CONFIG_PINCTRL */
2268 /* These "optional" allocation calls help prevent drivers from stomping
2269 * on each other, and help provide better diagnostics in debugfs.
2270 * They're called even less than the "set direction" calls.
2272 static int gpiod_request_commit(struct gpio_desc
*desc
, const char *label
)
2274 struct gpio_chip
*chip
= desc
->gdev
->chip
;
2276 unsigned long flags
;
2280 label
= kstrdup_const(label
, GFP_KERNEL
);
2285 spin_lock_irqsave(&gpio_lock
, flags
);
2287 /* NOTE: gpio_request() can be called in early boot,
2288 * before IRQs are enabled, for non-sleeping (SOC) GPIOs.
2291 if (test_and_set_bit(FLAG_REQUESTED
, &desc
->flags
) == 0) {
2292 desc_set_label(desc
, label
? : "?");
2300 if (chip
->request
) {
2301 /* chip->request may sleep */
2302 spin_unlock_irqrestore(&gpio_lock
, flags
);
2303 offset
= gpio_chip_hwgpio(desc
);
2304 if (gpiochip_line_is_valid(chip
, offset
))
2305 status
= chip
->request(chip
, offset
);
2308 spin_lock_irqsave(&gpio_lock
, flags
);
2311 desc_set_label(desc
, NULL
);
2313 clear_bit(FLAG_REQUESTED
, &desc
->flags
);
2317 if (chip
->get_direction
) {
2318 /* chip->get_direction may sleep */
2319 spin_unlock_irqrestore(&gpio_lock
, flags
);
2320 gpiod_get_direction(desc
);
2321 spin_lock_irqsave(&gpio_lock
, flags
);
2324 spin_unlock_irqrestore(&gpio_lock
, flags
);
2329 * This descriptor validation needs to be inserted verbatim into each
2330 * function taking a descriptor, so we need to use a preprocessor
2331 * macro to avoid endless duplication. If the desc is NULL it is an
2332 * optional GPIO and calls should just bail out.
2334 static int validate_desc(const struct gpio_desc
*desc
, const char *func
)
2339 pr_warn("%s: invalid GPIO (errorpointer)\n", func
);
2340 return PTR_ERR(desc
);
2343 pr_warn("%s: invalid GPIO (no device)\n", func
);
2346 if (!desc
->gdev
->chip
) {
2347 dev_warn(&desc
->gdev
->dev
,
2348 "%s: backing chip is gone\n", func
);
2354 #define VALIDATE_DESC(desc) do { \
2355 int __valid = validate_desc(desc, __func__); \
2360 #define VALIDATE_DESC_VOID(desc) do { \
2361 int __valid = validate_desc(desc, __func__); \
2366 int gpiod_request(struct gpio_desc
*desc
, const char *label
)
2368 int status
= -EPROBE_DEFER
;
2369 struct gpio_device
*gdev
;
2371 VALIDATE_DESC(desc
);
2374 if (try_module_get(gdev
->owner
)) {
2375 status
= gpiod_request_commit(desc
, label
);
2377 module_put(gdev
->owner
);
2379 get_device(&gdev
->dev
);
2383 gpiod_dbg(desc
, "%s: status %d\n", __func__
, status
);
2388 static bool gpiod_free_commit(struct gpio_desc
*desc
)
2391 unsigned long flags
;
2392 struct gpio_chip
*chip
;
2396 gpiod_unexport(desc
);
2398 spin_lock_irqsave(&gpio_lock
, flags
);
2400 chip
= desc
->gdev
->chip
;
2401 if (chip
&& test_bit(FLAG_REQUESTED
, &desc
->flags
)) {
2403 spin_unlock_irqrestore(&gpio_lock
, flags
);
2404 might_sleep_if(chip
->can_sleep
);
2405 chip
->free(chip
, gpio_chip_hwgpio(desc
));
2406 spin_lock_irqsave(&gpio_lock
, flags
);
2408 kfree_const(desc
->label
);
2409 desc_set_label(desc
, NULL
);
2410 clear_bit(FLAG_ACTIVE_LOW
, &desc
->flags
);
2411 clear_bit(FLAG_REQUESTED
, &desc
->flags
);
2412 clear_bit(FLAG_OPEN_DRAIN
, &desc
->flags
);
2413 clear_bit(FLAG_OPEN_SOURCE
, &desc
->flags
);
2414 clear_bit(FLAG_IS_HOGGED
, &desc
->flags
);
2418 spin_unlock_irqrestore(&gpio_lock
, flags
);
2422 void gpiod_free(struct gpio_desc
*desc
)
2424 if (desc
&& desc
->gdev
&& gpiod_free_commit(desc
)) {
2425 module_put(desc
->gdev
->owner
);
2426 put_device(&desc
->gdev
->dev
);
2428 WARN_ON(extra_checks
);
2433 * gpiochip_is_requested - return string iff signal was requested
2434 * @chip: controller managing the signal
2435 * @offset: of signal within controller's 0..(ngpio - 1) range
2437 * Returns NULL if the GPIO is not currently requested, else a string.
2438 * The string returned is the label passed to gpio_request(); if none has been
2439 * passed it is a meaningless, non-NULL constant.
2441 * This function is for use by GPIO controller drivers. The label can
2442 * help with diagnostics, and knowing that the signal is used as a GPIO
2443 * can help avoid accidentally multiplexing it to another controller.
2445 const char *gpiochip_is_requested(struct gpio_chip
*chip
, unsigned offset
)
2447 struct gpio_desc
*desc
;
2449 if (offset
>= chip
->ngpio
)
2452 desc
= &chip
->gpiodev
->descs
[offset
];
2454 if (test_bit(FLAG_REQUESTED
, &desc
->flags
) == 0)
2458 EXPORT_SYMBOL_GPL(gpiochip_is_requested
);
2461 * gpiochip_request_own_desc - Allow GPIO chip to request its own descriptor
2463 * @hwnum: hardware number of the GPIO for which to request the descriptor
2464 * @label: label for the GPIO
2465 * @flags: flags for this GPIO or 0 if default
2467 * Function allows GPIO chip drivers to request and use their own GPIO
2468 * descriptors via gpiolib API. Difference to gpiod_request() is that this
2469 * function will not increase reference count of the GPIO chip module. This
2470 * allows the GPIO chip module to be unloaded as needed (we assume that the
2471 * GPIO chip driver handles freeing the GPIOs it has requested).
2474 * A pointer to the GPIO descriptor, or an ERR_PTR()-encoded negative error
2477 struct gpio_desc
*gpiochip_request_own_desc(struct gpio_chip
*chip
, u16 hwnum
,
2479 enum gpiod_flags flags
)
2481 struct gpio_desc
*desc
= gpiochip_get_desc(chip
, hwnum
);
2485 chip_err(chip
, "failed to get GPIO descriptor\n");
2489 err
= gpiod_request_commit(desc
, label
);
2491 return ERR_PTR(err
);
2493 err
= gpiod_configure_flags(desc
, label
, 0, flags
);
2495 chip_err(chip
, "setup of own GPIO %s failed\n", label
);
2496 gpiod_free_commit(desc
);
2497 return ERR_PTR(err
);
2502 EXPORT_SYMBOL_GPL(gpiochip_request_own_desc
);
2505 * gpiochip_free_own_desc - Free GPIO requested by the chip driver
2506 * @desc: GPIO descriptor to free
2508 * Function frees the given GPIO requested previously with
2509 * gpiochip_request_own_desc().
2511 void gpiochip_free_own_desc(struct gpio_desc
*desc
)
2514 gpiod_free_commit(desc
);
2516 EXPORT_SYMBOL_GPL(gpiochip_free_own_desc
);
2519 * Drivers MUST set GPIO direction before making get/set calls. In
2520 * some cases this is done in early boot, before IRQs are enabled.
2522 * As a rule these aren't called more than once (except for drivers
2523 * using the open-drain emulation idiom) so these are natural places
2524 * to accumulate extra debugging checks. Note that we can't (yet)
2525 * rely on gpio_request() having been called beforehand.
2529 * gpiod_direction_input - set the GPIO direction to input
2530 * @desc: GPIO to set to input
2532 * Set the direction of the passed GPIO to input, such as gpiod_get_value() can
2533 * be called safely on it.
2535 * Return 0 in case of success, else an error code.
2537 int gpiod_direction_input(struct gpio_desc
*desc
)
2539 struct gpio_chip
*chip
;
2542 VALIDATE_DESC(desc
);
2543 chip
= desc
->gdev
->chip
;
2546 * It is legal to have no .get() and .direction_input() specified if
2547 * the chip is output-only, but you can't specify .direction_input()
2548 * and not support the .get() operation, that doesn't make sense.
2550 if (!chip
->get
&& chip
->direction_input
) {
2552 "%s: missing get() but have direction_input()\n",
2558 * If we have a .direction_input() callback, things are simple,
2559 * just call it. Else we are some input-only chip so try to check the
2560 * direction (if .get_direction() is supported) else we silently
2561 * assume we are in input mode after this.
2563 if (chip
->direction_input
) {
2564 status
= chip
->direction_input(chip
, gpio_chip_hwgpio(desc
));
2565 } else if (chip
->get_direction
&&
2566 (chip
->get_direction(chip
, gpio_chip_hwgpio(desc
)) != 1)) {
2568 "%s: missing direction_input() operation and line is output\n",
2573 clear_bit(FLAG_IS_OUT
, &desc
->flags
);
2575 trace_gpio_direction(desc_to_gpio(desc
), 1, status
);
2579 EXPORT_SYMBOL_GPL(gpiod_direction_input
);
2581 static int gpio_set_drive_single_ended(struct gpio_chip
*gc
, unsigned offset
,
2582 enum pin_config_param mode
)
2584 unsigned long config
= { PIN_CONF_PACKED(mode
, 0) };
2586 return gc
->set_config
? gc
->set_config(gc
, offset
, config
) : -ENOTSUPP
;
2589 static int gpiod_direction_output_raw_commit(struct gpio_desc
*desc
, int value
)
2591 struct gpio_chip
*gc
= desc
->gdev
->chip
;
2596 * It's OK not to specify .direction_output() if the gpiochip is
2597 * output-only, but if there is then not even a .set() operation it
2598 * is pretty tricky to drive the output line.
2600 if (!gc
->set
&& !gc
->direction_output
) {
2602 "%s: missing set() and direction_output() operations\n",
2607 if (gc
->direction_output
) {
2608 ret
= gc
->direction_output(gc
, gpio_chip_hwgpio(desc
), val
);
2610 /* Check that we are in output mode if we can */
2611 if (gc
->get_direction
&&
2612 gc
->get_direction(gc
, gpio_chip_hwgpio(desc
))) {
2614 "%s: missing direction_output() operation\n",
2619 * If we can't actively set the direction, we are some
2620 * output-only chip, so just drive the output as desired.
2622 gc
->set(gc
, gpio_chip_hwgpio(desc
), val
);
2626 set_bit(FLAG_IS_OUT
, &desc
->flags
);
2627 trace_gpio_value(desc_to_gpio(desc
), 0, val
);
2628 trace_gpio_direction(desc_to_gpio(desc
), 0, ret
);
2633 * gpiod_direction_output_raw - set the GPIO direction to output
2634 * @desc: GPIO to set to output
2635 * @value: initial output value of the GPIO
2637 * Set the direction of the passed GPIO to output, such as gpiod_set_value() can
2638 * be called safely on it. The initial value of the output must be specified
2639 * as raw value on the physical line without regard for the ACTIVE_LOW status.
2641 * Return 0 in case of success, else an error code.
2643 int gpiod_direction_output_raw(struct gpio_desc
*desc
, int value
)
2645 VALIDATE_DESC(desc
);
2646 return gpiod_direction_output_raw_commit(desc
, value
);
2648 EXPORT_SYMBOL_GPL(gpiod_direction_output_raw
);
2651 * gpiod_direction_output - set the GPIO direction to output
2652 * @desc: GPIO to set to output
2653 * @value: initial output value of the GPIO
2655 * Set the direction of the passed GPIO to output, such as gpiod_set_value() can
2656 * be called safely on it. The initial value of the output must be specified
2657 * as the logical value of the GPIO, i.e. taking its ACTIVE_LOW status into
2660 * Return 0 in case of success, else an error code.
2662 int gpiod_direction_output(struct gpio_desc
*desc
, int value
)
2664 struct gpio_chip
*gc
;
2667 VALIDATE_DESC(desc
);
2668 if (test_bit(FLAG_ACTIVE_LOW
, &desc
->flags
))
2673 /* GPIOs used for enabled IRQs shall not be set as output */
2674 if (test_bit(FLAG_USED_AS_IRQ
, &desc
->flags
) &&
2675 test_bit(FLAG_IRQ_IS_ENABLED
, &desc
->flags
)) {
2677 "%s: tried to set a GPIO tied to an IRQ as output\n",
2682 gc
= desc
->gdev
->chip
;
2683 if (test_bit(FLAG_OPEN_DRAIN
, &desc
->flags
)) {
2684 /* First see if we can enable open drain in hardware */
2685 ret
= gpio_set_drive_single_ended(gc
, gpio_chip_hwgpio(desc
),
2686 PIN_CONFIG_DRIVE_OPEN_DRAIN
);
2688 goto set_output_value
;
2689 /* Emulate open drain by not actively driving the line high */
2691 return gpiod_direction_input(desc
);
2693 else if (test_bit(FLAG_OPEN_SOURCE
, &desc
->flags
)) {
2694 ret
= gpio_set_drive_single_ended(gc
, gpio_chip_hwgpio(desc
),
2695 PIN_CONFIG_DRIVE_OPEN_SOURCE
);
2697 goto set_output_value
;
2698 /* Emulate open source by not actively driving the line low */
2700 return gpiod_direction_input(desc
);
2702 gpio_set_drive_single_ended(gc
, gpio_chip_hwgpio(desc
),
2703 PIN_CONFIG_DRIVE_PUSH_PULL
);
2707 return gpiod_direction_output_raw_commit(desc
, value
);
2709 EXPORT_SYMBOL_GPL(gpiod_direction_output
);
2712 * gpiod_set_debounce - sets @debounce time for a GPIO
2713 * @desc: descriptor of the GPIO for which to set debounce time
2714 * @debounce: debounce time in microseconds
2717 * 0 on success, %-ENOTSUPP if the controller doesn't support setting the
2720 int gpiod_set_debounce(struct gpio_desc
*desc
, unsigned debounce
)
2722 struct gpio_chip
*chip
;
2723 unsigned long config
;
2725 VALIDATE_DESC(desc
);
2726 chip
= desc
->gdev
->chip
;
2727 if (!chip
->set
|| !chip
->set_config
) {
2729 "%s: missing set() or set_config() operations\n",
2734 config
= pinconf_to_config_packed(PIN_CONFIG_INPUT_DEBOUNCE
, debounce
);
2735 return chip
->set_config(chip
, gpio_chip_hwgpio(desc
), config
);
2737 EXPORT_SYMBOL_GPL(gpiod_set_debounce
);
2740 * gpiod_set_transitory - Lose or retain GPIO state on suspend or reset
2741 * @desc: descriptor of the GPIO for which to configure persistence
2742 * @transitory: True to lose state on suspend or reset, false for persistence
2745 * 0 on success, otherwise a negative error code.
2747 int gpiod_set_transitory(struct gpio_desc
*desc
, bool transitory
)
2749 struct gpio_chip
*chip
;
2750 unsigned long packed
;
2754 VALIDATE_DESC(desc
);
2756 * Handle FLAG_TRANSITORY first, enabling queries to gpiolib for
2757 * persistence state.
2760 set_bit(FLAG_TRANSITORY
, &desc
->flags
);
2762 clear_bit(FLAG_TRANSITORY
, &desc
->flags
);
2764 /* If the driver supports it, set the persistence state now */
2765 chip
= desc
->gdev
->chip
;
2766 if (!chip
->set_config
)
2769 packed
= pinconf_to_config_packed(PIN_CONFIG_PERSIST_STATE
,
2771 gpio
= gpio_chip_hwgpio(desc
);
2772 rc
= chip
->set_config(chip
, gpio
, packed
);
2773 if (rc
== -ENOTSUPP
) {
2774 dev_dbg(&desc
->gdev
->dev
, "Persistence not supported for GPIO %d\n",
2781 EXPORT_SYMBOL_GPL(gpiod_set_transitory
);
2784 * gpiod_is_active_low - test whether a GPIO is active-low or not
2785 * @desc: the gpio descriptor to test
2787 * Returns 1 if the GPIO is active-low, 0 otherwise.
2789 int gpiod_is_active_low(const struct gpio_desc
*desc
)
2791 VALIDATE_DESC(desc
);
2792 return test_bit(FLAG_ACTIVE_LOW
, &desc
->flags
);
2794 EXPORT_SYMBOL_GPL(gpiod_is_active_low
);
2796 /* I/O calls are only valid after configuration completed; the relevant
2797 * "is this a valid GPIO" error checks should already have been done.
2799 * "Get" operations are often inlinable as reading a pin value register,
2800 * and masking the relevant bit in that register.
2802 * When "set" operations are inlinable, they involve writing that mask to
2803 * one register to set a low value, or a different register to set it high.
2804 * Otherwise locking is needed, so there may be little value to inlining.
2806 *------------------------------------------------------------------------
2808 * IMPORTANT!!! The hot paths -- get/set value -- assume that callers
2809 * have requested the GPIO. That can include implicit requesting by
2810 * a direction setting call. Marking a gpio as requested locks its chip
2811 * in memory, guaranteeing that these table lookups need no more locking
2812 * and that gpiochip_remove() will fail.
2814 * REVISIT when debugging, consider adding some instrumentation to ensure
2815 * that the GPIO was actually requested.
2818 static int gpiod_get_raw_value_commit(const struct gpio_desc
*desc
)
2820 struct gpio_chip
*chip
;
2824 chip
= desc
->gdev
->chip
;
2825 offset
= gpio_chip_hwgpio(desc
);
2826 value
= chip
->get
? chip
->get(chip
, offset
) : -EIO
;
2827 value
= value
< 0 ? value
: !!value
;
2828 trace_gpio_value(desc_to_gpio(desc
), 1, value
);
2832 static int gpio_chip_get_multiple(struct gpio_chip
*chip
,
2833 unsigned long *mask
, unsigned long *bits
)
2835 if (chip
->get_multiple
) {
2836 return chip
->get_multiple(chip
, mask
, bits
);
2837 } else if (chip
->get
) {
2840 for_each_set_bit(i
, mask
, chip
->ngpio
) {
2841 value
= chip
->get(chip
, i
);
2844 __assign_bit(i
, bits
, value
);
2851 int gpiod_get_array_value_complex(bool raw
, bool can_sleep
,
2852 unsigned int array_size
,
2853 struct gpio_desc
**desc_array
,
2854 struct gpio_array
*array_info
,
2855 unsigned long *value_bitmap
)
2860 * Validate array_info against desc_array and its size.
2861 * It should immediately follow desc_array if both
2862 * have been obtained from the same gpiod_get_array() call.
2864 if (array_info
&& array_info
->desc
== desc_array
&&
2865 array_size
<= array_info
->size
&&
2866 (void *)array_info
== desc_array
+ array_info
->size
) {
2868 WARN_ON(array_info
->chip
->can_sleep
);
2870 err
= gpio_chip_get_multiple(array_info
->chip
,
2871 array_info
->get_mask
,
2876 if (!raw
&& !bitmap_empty(array_info
->invert_mask
, array_size
))
2877 bitmap_xor(value_bitmap
, value_bitmap
,
2878 array_info
->invert_mask
, array_size
);
2880 if (bitmap_full(array_info
->get_mask
, array_size
))
2883 i
= find_first_zero_bit(array_info
->get_mask
, array_size
);
2888 while (i
< array_size
) {
2889 struct gpio_chip
*chip
= desc_array
[i
]->gdev
->chip
;
2890 unsigned long fastpath
[2 * BITS_TO_LONGS(FASTPATH_NGPIO
)];
2891 unsigned long *mask
, *bits
;
2894 if (likely(chip
->ngpio
<= FASTPATH_NGPIO
)) {
2897 mask
= kmalloc_array(2 * BITS_TO_LONGS(chip
->ngpio
),
2899 can_sleep
? GFP_KERNEL
: GFP_ATOMIC
);
2904 bits
= mask
+ BITS_TO_LONGS(chip
->ngpio
);
2905 bitmap_zero(mask
, chip
->ngpio
);
2908 WARN_ON(chip
->can_sleep
);
2910 /* collect all inputs belonging to the same chip */
2913 const struct gpio_desc
*desc
= desc_array
[i
];
2914 int hwgpio
= gpio_chip_hwgpio(desc
);
2916 __set_bit(hwgpio
, mask
);
2920 i
= find_next_zero_bit(array_info
->get_mask
,
2922 } while ((i
< array_size
) &&
2923 (desc_array
[i
]->gdev
->chip
== chip
));
2925 ret
= gpio_chip_get_multiple(chip
, mask
, bits
);
2927 if (mask
!= fastpath
)
2932 for (j
= first
; j
< i
; ) {
2933 const struct gpio_desc
*desc
= desc_array
[j
];
2934 int hwgpio
= gpio_chip_hwgpio(desc
);
2935 int value
= test_bit(hwgpio
, bits
);
2937 if (!raw
&& test_bit(FLAG_ACTIVE_LOW
, &desc
->flags
))
2939 __assign_bit(j
, value_bitmap
, value
);
2940 trace_gpio_value(desc_to_gpio(desc
), 1, value
);
2944 j
= find_next_zero_bit(array_info
->get_mask
, i
,
2948 if (mask
!= fastpath
)
2955 * gpiod_get_raw_value() - return a gpio's raw value
2956 * @desc: gpio whose value will be returned
2958 * Return the GPIO's raw value, i.e. the value of the physical line disregarding
2959 * its ACTIVE_LOW status, or negative errno on failure.
2961 * This function should be called from contexts where we cannot sleep, and will
2962 * complain if the GPIO chip functions potentially sleep.
2964 int gpiod_get_raw_value(const struct gpio_desc
*desc
)
2966 VALIDATE_DESC(desc
);
2967 /* Should be using gpio_get_value_cansleep() */
2968 WARN_ON(desc
->gdev
->chip
->can_sleep
);
2969 return gpiod_get_raw_value_commit(desc
);
2971 EXPORT_SYMBOL_GPL(gpiod_get_raw_value
);
2974 * gpiod_get_value() - return a gpio's value
2975 * @desc: gpio whose value will be returned
2977 * Return the GPIO's logical value, i.e. taking the ACTIVE_LOW status into
2978 * account, or negative errno on failure.
2980 * This function should be called from contexts where we cannot sleep, and will
2981 * complain if the GPIO chip functions potentially sleep.
2983 int gpiod_get_value(const struct gpio_desc
*desc
)
2987 VALIDATE_DESC(desc
);
2988 /* Should be using gpio_get_value_cansleep() */
2989 WARN_ON(desc
->gdev
->chip
->can_sleep
);
2991 value
= gpiod_get_raw_value_commit(desc
);
2995 if (test_bit(FLAG_ACTIVE_LOW
, &desc
->flags
))
3000 EXPORT_SYMBOL_GPL(gpiod_get_value
);
3003 * gpiod_get_raw_array_value() - read raw values from an array of GPIOs
3004 * @array_size: number of elements in the descriptor array / value bitmap
3005 * @desc_array: array of GPIO descriptors whose values will be read
3006 * @array_info: information on applicability of fast bitmap processing path
3007 * @value_bitmap: bitmap to store the read values
3009 * Read the raw values of the GPIOs, i.e. the values of the physical lines
3010 * without regard for their ACTIVE_LOW status. Return 0 in case of success,
3011 * else an error code.
3013 * This function should be called from contexts where we cannot sleep,
3014 * and it will complain if the GPIO chip functions potentially sleep.
3016 int gpiod_get_raw_array_value(unsigned int array_size
,
3017 struct gpio_desc
**desc_array
,
3018 struct gpio_array
*array_info
,
3019 unsigned long *value_bitmap
)
3023 return gpiod_get_array_value_complex(true, false, array_size
,
3024 desc_array
, array_info
,
3027 EXPORT_SYMBOL_GPL(gpiod_get_raw_array_value
);
3030 * gpiod_get_array_value() - read values from an array of GPIOs
3031 * @array_size: number of elements in the descriptor array / value bitmap
3032 * @desc_array: array of GPIO descriptors whose values will be read
3033 * @array_info: information on applicability of fast bitmap processing path
3034 * @value_bitmap: bitmap to store the read values
3036 * Read the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status
3037 * into account. Return 0 in case of success, else an error code.
3039 * This function should be called from contexts where we cannot sleep,
3040 * and it will complain if the GPIO chip functions potentially sleep.
3042 int gpiod_get_array_value(unsigned int array_size
,
3043 struct gpio_desc
**desc_array
,
3044 struct gpio_array
*array_info
,
3045 unsigned long *value_bitmap
)
3049 return gpiod_get_array_value_complex(false, false, array_size
,
3050 desc_array
, array_info
,
3053 EXPORT_SYMBOL_GPL(gpiod_get_array_value
);
3056 * gpio_set_open_drain_value_commit() - Set the open drain gpio's value.
3057 * @desc: gpio descriptor whose state need to be set.
3058 * @value: Non-zero for setting it HIGH otherwise it will set to LOW.
3060 static void gpio_set_open_drain_value_commit(struct gpio_desc
*desc
, bool value
)
3063 struct gpio_chip
*chip
= desc
->gdev
->chip
;
3064 int offset
= gpio_chip_hwgpio(desc
);
3067 err
= chip
->direction_input(chip
, offset
);
3069 clear_bit(FLAG_IS_OUT
, &desc
->flags
);
3071 err
= chip
->direction_output(chip
, offset
, 0);
3073 set_bit(FLAG_IS_OUT
, &desc
->flags
);
3075 trace_gpio_direction(desc_to_gpio(desc
), value
, err
);
3078 "%s: Error in set_value for open drain err %d\n",
3083 * _gpio_set_open_source_value() - Set the open source gpio's value.
3084 * @desc: gpio descriptor whose state need to be set.
3085 * @value: Non-zero for setting it HIGH otherwise it will set to LOW.
3087 static void gpio_set_open_source_value_commit(struct gpio_desc
*desc
, bool value
)
3090 struct gpio_chip
*chip
= desc
->gdev
->chip
;
3091 int offset
= gpio_chip_hwgpio(desc
);
3094 err
= chip
->direction_output(chip
, offset
, 1);
3096 set_bit(FLAG_IS_OUT
, &desc
->flags
);
3098 err
= chip
->direction_input(chip
, offset
);
3100 clear_bit(FLAG_IS_OUT
, &desc
->flags
);
3102 trace_gpio_direction(desc_to_gpio(desc
), !value
, err
);
3105 "%s: Error in set_value for open source err %d\n",
3109 static void gpiod_set_raw_value_commit(struct gpio_desc
*desc
, bool value
)
3111 struct gpio_chip
*chip
;
3113 chip
= desc
->gdev
->chip
;
3114 trace_gpio_value(desc_to_gpio(desc
), 0, value
);
3115 chip
->set(chip
, gpio_chip_hwgpio(desc
), value
);
3119 * set multiple outputs on the same chip;
3120 * use the chip's set_multiple function if available;
3121 * otherwise set the outputs sequentially;
3122 * @mask: bit mask array; one bit per output; BITS_PER_LONG bits per word
3123 * defines which outputs are to be changed
3124 * @bits: bit value array; one bit per output; BITS_PER_LONG bits per word
3125 * defines the values the outputs specified by mask are to be set to
3127 static void gpio_chip_set_multiple(struct gpio_chip
*chip
,
3128 unsigned long *mask
, unsigned long *bits
)
3130 if (chip
->set_multiple
) {
3131 chip
->set_multiple(chip
, mask
, bits
);
3135 /* set outputs if the corresponding mask bit is set */
3136 for_each_set_bit(i
, mask
, chip
->ngpio
)
3137 chip
->set(chip
, i
, test_bit(i
, bits
));
3141 int gpiod_set_array_value_complex(bool raw
, bool can_sleep
,
3142 unsigned int array_size
,
3143 struct gpio_desc
**desc_array
,
3144 struct gpio_array
*array_info
,
3145 unsigned long *value_bitmap
)
3150 * Validate array_info against desc_array and its size.
3151 * It should immediately follow desc_array if both
3152 * have been obtained from the same gpiod_get_array() call.
3154 if (array_info
&& array_info
->desc
== desc_array
&&
3155 array_size
<= array_info
->size
&&
3156 (void *)array_info
== desc_array
+ array_info
->size
) {
3158 WARN_ON(array_info
->chip
->can_sleep
);
3160 if (!raw
&& !bitmap_empty(array_info
->invert_mask
, array_size
))
3161 bitmap_xor(value_bitmap
, value_bitmap
,
3162 array_info
->invert_mask
, array_size
);
3164 gpio_chip_set_multiple(array_info
->chip
, array_info
->set_mask
,
3167 if (bitmap_full(array_info
->set_mask
, array_size
))
3170 i
= find_first_zero_bit(array_info
->set_mask
, array_size
);
3175 while (i
< array_size
) {
3176 struct gpio_chip
*chip
= desc_array
[i
]->gdev
->chip
;
3177 unsigned long fastpath
[2 * BITS_TO_LONGS(FASTPATH_NGPIO
)];
3178 unsigned long *mask
, *bits
;
3181 if (likely(chip
->ngpio
<= FASTPATH_NGPIO
)) {
3184 mask
= kmalloc_array(2 * BITS_TO_LONGS(chip
->ngpio
),
3186 can_sleep
? GFP_KERNEL
: GFP_ATOMIC
);
3191 bits
= mask
+ BITS_TO_LONGS(chip
->ngpio
);
3192 bitmap_zero(mask
, chip
->ngpio
);
3195 WARN_ON(chip
->can_sleep
);
3198 struct gpio_desc
*desc
= desc_array
[i
];
3199 int hwgpio
= gpio_chip_hwgpio(desc
);
3200 int value
= test_bit(i
, value_bitmap
);
3203 * Pins applicable for fast input but not for
3204 * fast output processing may have been already
3205 * inverted inside the fast path, skip them.
3207 if (!raw
&& !(array_info
&&
3208 test_bit(i
, array_info
->invert_mask
)) &&
3209 test_bit(FLAG_ACTIVE_LOW
, &desc
->flags
))
3211 trace_gpio_value(desc_to_gpio(desc
), 0, value
);
3213 * collect all normal outputs belonging to the same chip
3214 * open drain and open source outputs are set individually
3216 if (test_bit(FLAG_OPEN_DRAIN
, &desc
->flags
) && !raw
) {
3217 gpio_set_open_drain_value_commit(desc
, value
);
3218 } else if (test_bit(FLAG_OPEN_SOURCE
, &desc
->flags
) && !raw
) {
3219 gpio_set_open_source_value_commit(desc
, value
);
3221 __set_bit(hwgpio
, mask
);
3223 __set_bit(hwgpio
, bits
);
3225 __clear_bit(hwgpio
, bits
);
3231 i
= find_next_zero_bit(array_info
->set_mask
,
3233 } while ((i
< array_size
) &&
3234 (desc_array
[i
]->gdev
->chip
== chip
));
3235 /* push collected bits to outputs */
3237 gpio_chip_set_multiple(chip
, mask
, bits
);
3239 if (mask
!= fastpath
)
3246 * gpiod_set_raw_value() - assign a gpio's raw value
3247 * @desc: gpio whose value will be assigned
3248 * @value: value to assign
3250 * Set the raw value of the GPIO, i.e. the value of its physical line without
3251 * regard for its ACTIVE_LOW status.
3253 * This function should be called from contexts where we cannot sleep, and will
3254 * complain if the GPIO chip functions potentially sleep.
3256 void gpiod_set_raw_value(struct gpio_desc
*desc
, int value
)
3258 VALIDATE_DESC_VOID(desc
);
3259 /* Should be using gpiod_set_value_cansleep() */
3260 WARN_ON(desc
->gdev
->chip
->can_sleep
);
3261 gpiod_set_raw_value_commit(desc
, value
);
3263 EXPORT_SYMBOL_GPL(gpiod_set_raw_value
);
3266 * gpiod_set_value_nocheck() - set a GPIO line value without checking
3267 * @desc: the descriptor to set the value on
3268 * @value: value to set
3270 * This sets the value of a GPIO line backing a descriptor, applying
3271 * different semantic quirks like active low and open drain/source
3274 static void gpiod_set_value_nocheck(struct gpio_desc
*desc
, int value
)
3276 if (test_bit(FLAG_ACTIVE_LOW
, &desc
->flags
))
3278 if (test_bit(FLAG_OPEN_DRAIN
, &desc
->flags
))
3279 gpio_set_open_drain_value_commit(desc
, value
);
3280 else if (test_bit(FLAG_OPEN_SOURCE
, &desc
->flags
))
3281 gpio_set_open_source_value_commit(desc
, value
);
3283 gpiod_set_raw_value_commit(desc
, value
);
3287 * gpiod_set_value() - assign a gpio's value
3288 * @desc: gpio whose value will be assigned
3289 * @value: value to assign
3291 * Set the logical value of the GPIO, i.e. taking its ACTIVE_LOW,
3292 * OPEN_DRAIN and OPEN_SOURCE flags into account.
3294 * This function should be called from contexts where we cannot sleep, and will
3295 * complain if the GPIO chip functions potentially sleep.
3297 void gpiod_set_value(struct gpio_desc
*desc
, int value
)
3299 VALIDATE_DESC_VOID(desc
);
3300 WARN_ON(desc
->gdev
->chip
->can_sleep
);
3301 gpiod_set_value_nocheck(desc
, value
);
3303 EXPORT_SYMBOL_GPL(gpiod_set_value
);
3306 * gpiod_set_raw_array_value() - assign values to an array of GPIOs
3307 * @array_size: number of elements in the descriptor array / value bitmap
3308 * @desc_array: array of GPIO descriptors whose values will be assigned
3309 * @array_info: information on applicability of fast bitmap processing path
3310 * @value_bitmap: bitmap of values to assign
3312 * Set the raw values of the GPIOs, i.e. the values of the physical lines
3313 * without regard for their ACTIVE_LOW status.
3315 * This function should be called from contexts where we cannot sleep, and will
3316 * complain if the GPIO chip functions potentially sleep.
3318 int gpiod_set_raw_array_value(unsigned int array_size
,
3319 struct gpio_desc
**desc_array
,
3320 struct gpio_array
*array_info
,
3321 unsigned long *value_bitmap
)
3325 return gpiod_set_array_value_complex(true, false, array_size
,
3326 desc_array
, array_info
, value_bitmap
);
3328 EXPORT_SYMBOL_GPL(gpiod_set_raw_array_value
);
3331 * gpiod_set_array_value() - assign values to an array of GPIOs
3332 * @array_size: number of elements in the descriptor array / value bitmap
3333 * @desc_array: array of GPIO descriptors whose values will be assigned
3334 * @array_info: information on applicability of fast bitmap processing path
3335 * @value_bitmap: bitmap of values to assign
3337 * Set the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status
3340 * This function should be called from contexts where we cannot sleep, and will
3341 * complain if the GPIO chip functions potentially sleep.
3343 int gpiod_set_array_value(unsigned int array_size
,
3344 struct gpio_desc
**desc_array
,
3345 struct gpio_array
*array_info
,
3346 unsigned long *value_bitmap
)
3350 return gpiod_set_array_value_complex(false, false, array_size
,
3351 desc_array
, array_info
,
3354 EXPORT_SYMBOL_GPL(gpiod_set_array_value
);
3357 * gpiod_cansleep() - report whether gpio value access may sleep
3358 * @desc: gpio to check
3361 int gpiod_cansleep(const struct gpio_desc
*desc
)
3363 VALIDATE_DESC(desc
);
3364 return desc
->gdev
->chip
->can_sleep
;
3366 EXPORT_SYMBOL_GPL(gpiod_cansleep
);
3369 * gpiod_set_consumer_name() - set the consumer name for the descriptor
3370 * @desc: gpio to set the consumer name on
3371 * @name: the new consumer name
3373 int gpiod_set_consumer_name(struct gpio_desc
*desc
, const char *name
)
3375 VALIDATE_DESC(desc
);
3377 name
= kstrdup_const(name
, GFP_KERNEL
);
3382 kfree_const(desc
->label
);
3383 desc_set_label(desc
, name
);
3387 EXPORT_SYMBOL_GPL(gpiod_set_consumer_name
);
3390 * gpiod_to_irq() - return the IRQ corresponding to a GPIO
3391 * @desc: gpio whose IRQ will be returned (already requested)
3393 * Return the IRQ corresponding to the passed GPIO, or an error code in case of
3396 int gpiod_to_irq(const struct gpio_desc
*desc
)
3398 struct gpio_chip
*chip
;
3402 * Cannot VALIDATE_DESC() here as gpiod_to_irq() consumer semantics
3403 * requires this function to not return zero on an invalid descriptor
3404 * but rather a negative error number.
3406 if (!desc
|| IS_ERR(desc
) || !desc
->gdev
|| !desc
->gdev
->chip
)
3409 chip
= desc
->gdev
->chip
;
3410 offset
= gpio_chip_hwgpio(desc
);
3412 int retirq
= chip
->to_irq(chip
, offset
);
3414 /* Zero means NO_IRQ */
3422 EXPORT_SYMBOL_GPL(gpiod_to_irq
);
3425 * gpiochip_lock_as_irq() - lock a GPIO to be used as IRQ
3426 * @chip: the chip the GPIO to lock belongs to
3427 * @offset: the offset of the GPIO to lock as IRQ
3429 * This is used directly by GPIO drivers that want to lock down
3430 * a certain GPIO line to be used for IRQs.
3432 int gpiochip_lock_as_irq(struct gpio_chip
*chip
, unsigned int offset
)
3434 struct gpio_desc
*desc
;
3436 desc
= gpiochip_get_desc(chip
, offset
);
3438 return PTR_ERR(desc
);
3441 * If it's fast: flush the direction setting if something changed
3444 if (!chip
->can_sleep
&& chip
->get_direction
) {
3445 int dir
= gpiod_get_direction(desc
);
3448 chip_err(chip
, "%s: cannot get GPIO direction\n",
3454 if (test_bit(FLAG_IS_OUT
, &desc
->flags
)) {
3456 "%s: tried to flag a GPIO set as output for IRQ\n",
3461 set_bit(FLAG_USED_AS_IRQ
, &desc
->flags
);
3462 set_bit(FLAG_IRQ_IS_ENABLED
, &desc
->flags
);
3465 * If the consumer has not set up a label (such as when the
3466 * IRQ is referenced from .to_irq()) we set up a label here
3467 * so it is clear this is used as an interrupt.
3470 desc_set_label(desc
, "interrupt");
3474 EXPORT_SYMBOL_GPL(gpiochip_lock_as_irq
);
3477 * gpiochip_unlock_as_irq() - unlock a GPIO used as IRQ
3478 * @chip: the chip the GPIO to lock belongs to
3479 * @offset: the offset of the GPIO to lock as IRQ
3481 * This is used directly by GPIO drivers that want to indicate
3482 * that a certain GPIO is no longer used exclusively for IRQ.
3484 void gpiochip_unlock_as_irq(struct gpio_chip
*chip
, unsigned int offset
)
3486 struct gpio_desc
*desc
;
3488 desc
= gpiochip_get_desc(chip
, offset
);
3492 clear_bit(FLAG_USED_AS_IRQ
, &desc
->flags
);
3493 clear_bit(FLAG_IRQ_IS_ENABLED
, &desc
->flags
);
3495 /* If we only had this marking, erase it */
3496 if (desc
->label
&& !strcmp(desc
->label
, "interrupt"))
3497 desc_set_label(desc
, NULL
);
3499 EXPORT_SYMBOL_GPL(gpiochip_unlock_as_irq
);
3501 void gpiochip_disable_irq(struct gpio_chip
*chip
, unsigned int offset
)
3503 struct gpio_desc
*desc
= gpiochip_get_desc(chip
, offset
);
3505 if (!IS_ERR(desc
) &&
3506 !WARN_ON(!test_bit(FLAG_USED_AS_IRQ
, &desc
->flags
)))
3507 clear_bit(FLAG_IRQ_IS_ENABLED
, &desc
->flags
);
3509 EXPORT_SYMBOL_GPL(gpiochip_disable_irq
);
3511 void gpiochip_enable_irq(struct gpio_chip
*chip
, unsigned int offset
)
3513 struct gpio_desc
*desc
= gpiochip_get_desc(chip
, offset
);
3515 if (!IS_ERR(desc
) &&
3516 !WARN_ON(!test_bit(FLAG_USED_AS_IRQ
, &desc
->flags
))) {
3517 WARN_ON(test_bit(FLAG_IS_OUT
, &desc
->flags
));
3518 set_bit(FLAG_IRQ_IS_ENABLED
, &desc
->flags
);
3521 EXPORT_SYMBOL_GPL(gpiochip_enable_irq
);
3523 bool gpiochip_line_is_irq(struct gpio_chip
*chip
, unsigned int offset
)
3525 if (offset
>= chip
->ngpio
)
3528 return test_bit(FLAG_USED_AS_IRQ
, &chip
->gpiodev
->descs
[offset
].flags
);
3530 EXPORT_SYMBOL_GPL(gpiochip_line_is_irq
);
3532 int gpiochip_reqres_irq(struct gpio_chip
*chip
, unsigned int offset
)
3536 if (!try_module_get(chip
->gpiodev
->owner
))
3539 ret
= gpiochip_lock_as_irq(chip
, offset
);
3541 chip_err(chip
, "unable to lock HW IRQ %u for IRQ\n", offset
);
3542 module_put(chip
->gpiodev
->owner
);
3547 EXPORT_SYMBOL_GPL(gpiochip_reqres_irq
);
3549 void gpiochip_relres_irq(struct gpio_chip
*chip
, unsigned int offset
)
3551 gpiochip_unlock_as_irq(chip
, offset
);
3552 module_put(chip
->gpiodev
->owner
);
3554 EXPORT_SYMBOL_GPL(gpiochip_relres_irq
);
3556 bool gpiochip_line_is_open_drain(struct gpio_chip
*chip
, unsigned int offset
)
3558 if (offset
>= chip
->ngpio
)
3561 return test_bit(FLAG_OPEN_DRAIN
, &chip
->gpiodev
->descs
[offset
].flags
);
3563 EXPORT_SYMBOL_GPL(gpiochip_line_is_open_drain
);
3565 bool gpiochip_line_is_open_source(struct gpio_chip
*chip
, unsigned int offset
)
3567 if (offset
>= chip
->ngpio
)
3570 return test_bit(FLAG_OPEN_SOURCE
, &chip
->gpiodev
->descs
[offset
].flags
);
3572 EXPORT_SYMBOL_GPL(gpiochip_line_is_open_source
);
3574 bool gpiochip_line_is_persistent(struct gpio_chip
*chip
, unsigned int offset
)
3576 if (offset
>= chip
->ngpio
)
3579 return !test_bit(FLAG_TRANSITORY
, &chip
->gpiodev
->descs
[offset
].flags
);
3581 EXPORT_SYMBOL_GPL(gpiochip_line_is_persistent
);
3584 * gpiod_get_raw_value_cansleep() - return a gpio's raw value
3585 * @desc: gpio whose value will be returned
3587 * Return the GPIO's raw value, i.e. the value of the physical line disregarding
3588 * its ACTIVE_LOW status, or negative errno on failure.
3590 * This function is to be called from contexts that can sleep.
3592 int gpiod_get_raw_value_cansleep(const struct gpio_desc
*desc
)
3594 might_sleep_if(extra_checks
);
3595 VALIDATE_DESC(desc
);
3596 return gpiod_get_raw_value_commit(desc
);
3598 EXPORT_SYMBOL_GPL(gpiod_get_raw_value_cansleep
);
3601 * gpiod_get_value_cansleep() - return a gpio's value
3602 * @desc: gpio whose value will be returned
3604 * Return the GPIO's logical value, i.e. taking the ACTIVE_LOW status into
3605 * account, or negative errno on failure.
3607 * This function is to be called from contexts that can sleep.
3609 int gpiod_get_value_cansleep(const struct gpio_desc
*desc
)
3613 might_sleep_if(extra_checks
);
3614 VALIDATE_DESC(desc
);
3615 value
= gpiod_get_raw_value_commit(desc
);
3619 if (test_bit(FLAG_ACTIVE_LOW
, &desc
->flags
))
3624 EXPORT_SYMBOL_GPL(gpiod_get_value_cansleep
);
3627 * gpiod_get_raw_array_value_cansleep() - read raw values from an array of GPIOs
3628 * @array_size: number of elements in the descriptor array / value bitmap
3629 * @desc_array: array of GPIO descriptors whose values will be read
3630 * @array_info: information on applicability of fast bitmap processing path
3631 * @value_bitmap: bitmap to store the read values
3633 * Read the raw values of the GPIOs, i.e. the values of the physical lines
3634 * without regard for their ACTIVE_LOW status. Return 0 in case of success,
3635 * else an error code.
3637 * This function is to be called from contexts that can sleep.
3639 int gpiod_get_raw_array_value_cansleep(unsigned int array_size
,
3640 struct gpio_desc
**desc_array
,
3641 struct gpio_array
*array_info
,
3642 unsigned long *value_bitmap
)
3644 might_sleep_if(extra_checks
);
3647 return gpiod_get_array_value_complex(true, true, array_size
,
3648 desc_array
, array_info
,
3651 EXPORT_SYMBOL_GPL(gpiod_get_raw_array_value_cansleep
);
3654 * gpiod_get_array_value_cansleep() - read values from an array of GPIOs
3655 * @array_size: number of elements in the descriptor array / value bitmap
3656 * @desc_array: array of GPIO descriptors whose values will be read
3657 * @array_info: information on applicability of fast bitmap processing path
3658 * @value_bitmap: bitmap to store the read values
3660 * Read the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status
3661 * into account. Return 0 in case of success, else an error code.
3663 * This function is to be called from contexts that can sleep.
3665 int gpiod_get_array_value_cansleep(unsigned int array_size
,
3666 struct gpio_desc
**desc_array
,
3667 struct gpio_array
*array_info
,
3668 unsigned long *value_bitmap
)
3670 might_sleep_if(extra_checks
);
3673 return gpiod_get_array_value_complex(false, true, array_size
,
3674 desc_array
, array_info
,
3677 EXPORT_SYMBOL_GPL(gpiod_get_array_value_cansleep
);
3680 * gpiod_set_raw_value_cansleep() - assign a gpio's raw value
3681 * @desc: gpio whose value will be assigned
3682 * @value: value to assign
3684 * Set the raw value of the GPIO, i.e. the value of its physical line without
3685 * regard for its ACTIVE_LOW status.
3687 * This function is to be called from contexts that can sleep.
3689 void gpiod_set_raw_value_cansleep(struct gpio_desc
*desc
, int value
)
3691 might_sleep_if(extra_checks
);
3692 VALIDATE_DESC_VOID(desc
);
3693 gpiod_set_raw_value_commit(desc
, value
);
3695 EXPORT_SYMBOL_GPL(gpiod_set_raw_value_cansleep
);
3698 * gpiod_set_value_cansleep() - assign a gpio's value
3699 * @desc: gpio whose value will be assigned
3700 * @value: value to assign
3702 * Set the logical value of the GPIO, i.e. taking its ACTIVE_LOW status into
3705 * This function is to be called from contexts that can sleep.
3707 void gpiod_set_value_cansleep(struct gpio_desc
*desc
, int value
)
3709 might_sleep_if(extra_checks
);
3710 VALIDATE_DESC_VOID(desc
);
3711 gpiod_set_value_nocheck(desc
, value
);
3713 EXPORT_SYMBOL_GPL(gpiod_set_value_cansleep
);
3716 * gpiod_set_raw_array_value_cansleep() - assign values to an array of GPIOs
3717 * @array_size: number of elements in the descriptor array / value bitmap
3718 * @desc_array: array of GPIO descriptors whose values will be assigned
3719 * @array_info: information on applicability of fast bitmap processing path
3720 * @value_bitmap: bitmap of values to assign
3722 * Set the raw values of the GPIOs, i.e. the values of the physical lines
3723 * without regard for their ACTIVE_LOW status.
3725 * This function is to be called from contexts that can sleep.
3727 int gpiod_set_raw_array_value_cansleep(unsigned int array_size
,
3728 struct gpio_desc
**desc_array
,
3729 struct gpio_array
*array_info
,
3730 unsigned long *value_bitmap
)
3732 might_sleep_if(extra_checks
);
3735 return gpiod_set_array_value_complex(true, true, array_size
, desc_array
,
3736 array_info
, value_bitmap
);
3738 EXPORT_SYMBOL_GPL(gpiod_set_raw_array_value_cansleep
);
3741 * gpiod_add_lookup_tables() - register GPIO device consumers
3742 * @tables: list of tables of consumers to register
3743 * @n: number of tables in the list
3745 void gpiod_add_lookup_tables(struct gpiod_lookup_table
**tables
, size_t n
)
3749 mutex_lock(&gpio_lookup_lock
);
3751 for (i
= 0; i
< n
; i
++)
3752 list_add_tail(&tables
[i
]->list
, &gpio_lookup_list
);
3754 mutex_unlock(&gpio_lookup_lock
);
3758 * gpiod_set_array_value_cansleep() - assign values to an array of GPIOs
3759 * @array_size: number of elements in the descriptor array / value bitmap
3760 * @desc_array: array of GPIO descriptors whose values will be assigned
3761 * @array_info: information on applicability of fast bitmap processing path
3762 * @value_bitmap: bitmap of values to assign
3764 * Set the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status
3767 * This function is to be called from contexts that can sleep.
3769 int gpiod_set_array_value_cansleep(unsigned int array_size
,
3770 struct gpio_desc
**desc_array
,
3771 struct gpio_array
*array_info
,
3772 unsigned long *value_bitmap
)
3774 might_sleep_if(extra_checks
);
3777 return gpiod_set_array_value_complex(false, true, array_size
,
3778 desc_array
, array_info
,
3781 EXPORT_SYMBOL_GPL(gpiod_set_array_value_cansleep
);
3784 * gpiod_add_lookup_table() - register GPIO device consumers
3785 * @table: table of consumers to register
3787 void gpiod_add_lookup_table(struct gpiod_lookup_table
*table
)
3789 mutex_lock(&gpio_lookup_lock
);
3791 list_add_tail(&table
->list
, &gpio_lookup_list
);
3793 mutex_unlock(&gpio_lookup_lock
);
3795 EXPORT_SYMBOL_GPL(gpiod_add_lookup_table
);
3798 * gpiod_remove_lookup_table() - unregister GPIO device consumers
3799 * @table: table of consumers to unregister
3801 void gpiod_remove_lookup_table(struct gpiod_lookup_table
*table
)
3803 mutex_lock(&gpio_lookup_lock
);
3805 list_del(&table
->list
);
3807 mutex_unlock(&gpio_lookup_lock
);
3809 EXPORT_SYMBOL_GPL(gpiod_remove_lookup_table
);
3812 * gpiod_add_hogs() - register a set of GPIO hogs from machine code
3813 * @hogs: table of gpio hog entries with a zeroed sentinel at the end
3815 void gpiod_add_hogs(struct gpiod_hog
*hogs
)
3817 struct gpio_chip
*chip
;
3818 struct gpiod_hog
*hog
;
3820 mutex_lock(&gpio_machine_hogs_mutex
);
3822 for (hog
= &hogs
[0]; hog
->chip_label
; hog
++) {
3823 list_add_tail(&hog
->list
, &gpio_machine_hogs
);
3826 * The chip may have been registered earlier, so check if it
3827 * exists and, if so, try to hog the line now.
3829 chip
= find_chip_by_name(hog
->chip_label
);
3831 gpiochip_machine_hog(chip
, hog
);
3834 mutex_unlock(&gpio_machine_hogs_mutex
);
3836 EXPORT_SYMBOL_GPL(gpiod_add_hogs
);
3838 static struct gpiod_lookup_table
*gpiod_find_lookup_table(struct device
*dev
)
3840 const char *dev_id
= dev
? dev_name(dev
) : NULL
;
3841 struct gpiod_lookup_table
*table
;
3843 mutex_lock(&gpio_lookup_lock
);
3845 list_for_each_entry(table
, &gpio_lookup_list
, list
) {
3846 if (table
->dev_id
&& dev_id
) {
3848 * Valid strings on both ends, must be identical to have
3851 if (!strcmp(table
->dev_id
, dev_id
))
3855 * One of the pointers is NULL, so both must be to have
3858 if (dev_id
== table
->dev_id
)
3865 mutex_unlock(&gpio_lookup_lock
);
3869 static struct gpio_desc
*gpiod_find(struct device
*dev
, const char *con_id
,
3871 enum gpio_lookup_flags
*flags
)
3873 struct gpio_desc
*desc
= ERR_PTR(-ENOENT
);
3874 struct gpiod_lookup_table
*table
;
3875 struct gpiod_lookup
*p
;
3877 table
= gpiod_find_lookup_table(dev
);
3881 for (p
= &table
->table
[0]; p
->chip_label
; p
++) {
3882 struct gpio_chip
*chip
;
3884 /* idx must always match exactly */
3888 /* If the lookup entry has a con_id, require exact match */
3889 if (p
->con_id
&& (!con_id
|| strcmp(p
->con_id
, con_id
)))
3892 chip
= find_chip_by_name(p
->chip_label
);
3896 * As the lookup table indicates a chip with
3897 * p->chip_label should exist, assume it may
3898 * still appear later and let the interested
3899 * consumer be probed again or let the Deferred
3900 * Probe infrastructure handle the error.
3902 dev_warn(dev
, "cannot find GPIO chip %s, deferring\n",
3904 return ERR_PTR(-EPROBE_DEFER
);
3907 if (chip
->ngpio
<= p
->chip_hwnum
) {
3909 "requested GPIO %d is out of range [0..%d] for chip %s\n",
3910 idx
, chip
->ngpio
, chip
->label
);
3911 return ERR_PTR(-EINVAL
);
3914 desc
= gpiochip_get_desc(chip
, p
->chip_hwnum
);
3923 static int dt_gpio_count(struct device
*dev
, const char *con_id
)
3929 for (i
= 0; i
< ARRAY_SIZE(gpio_suffixes
); i
++) {
3931 snprintf(propname
, sizeof(propname
), "%s-%s",
3932 con_id
, gpio_suffixes
[i
]);
3934 snprintf(propname
, sizeof(propname
), "%s",
3937 ret
= of_gpio_named_count(dev
->of_node
, propname
);
3941 return ret
? ret
: -ENOENT
;
3944 static int platform_gpio_count(struct device
*dev
, const char *con_id
)
3946 struct gpiod_lookup_table
*table
;
3947 struct gpiod_lookup
*p
;
3948 unsigned int count
= 0;
3950 table
= gpiod_find_lookup_table(dev
);
3954 for (p
= &table
->table
[0]; p
->chip_label
; p
++) {
3955 if ((con_id
&& p
->con_id
&& !strcmp(con_id
, p
->con_id
)) ||
3956 (!con_id
&& !p
->con_id
))
3966 * gpiod_count - return the number of GPIOs associated with a device / function
3967 * or -ENOENT if no GPIO has been assigned to the requested function
3968 * @dev: GPIO consumer, can be NULL for system-global GPIOs
3969 * @con_id: function within the GPIO consumer
3971 int gpiod_count(struct device
*dev
, const char *con_id
)
3973 int count
= -ENOENT
;
3975 if (IS_ENABLED(CONFIG_OF
) && dev
&& dev
->of_node
)
3976 count
= dt_gpio_count(dev
, con_id
);
3977 else if (IS_ENABLED(CONFIG_ACPI
) && dev
&& ACPI_HANDLE(dev
))
3978 count
= acpi_gpio_count(dev
, con_id
);
3981 count
= platform_gpio_count(dev
, con_id
);
3985 EXPORT_SYMBOL_GPL(gpiod_count
);
3988 * gpiod_get - obtain a GPIO for a given GPIO function
3989 * @dev: GPIO consumer, can be NULL for system-global GPIOs
3990 * @con_id: function within the GPIO consumer
3991 * @flags: optional GPIO initialization flags
3993 * Return the GPIO descriptor corresponding to the function con_id of device
3994 * dev, -ENOENT if no GPIO has been assigned to the requested function, or
3995 * another IS_ERR() code if an error occurred while trying to acquire the GPIO.
3997 struct gpio_desc
*__must_check
gpiod_get(struct device
*dev
, const char *con_id
,
3998 enum gpiod_flags flags
)
4000 return gpiod_get_index(dev
, con_id
, 0, flags
);
4002 EXPORT_SYMBOL_GPL(gpiod_get
);
4005 * gpiod_get_optional - obtain an optional GPIO for a given GPIO function
4006 * @dev: GPIO consumer, can be NULL for system-global GPIOs
4007 * @con_id: function within the GPIO consumer
4008 * @flags: optional GPIO initialization flags
4010 * This is equivalent to gpiod_get(), except that when no GPIO was assigned to
4011 * the requested function it will return NULL. This is convenient for drivers
4012 * that need to handle optional GPIOs.
4014 struct gpio_desc
*__must_check
gpiod_get_optional(struct device
*dev
,
4016 enum gpiod_flags flags
)
4018 return gpiod_get_index_optional(dev
, con_id
, 0, flags
);
4020 EXPORT_SYMBOL_GPL(gpiod_get_optional
);
4024 * gpiod_configure_flags - helper function to configure a given GPIO
4025 * @desc: gpio whose value will be assigned
4026 * @con_id: function within the GPIO consumer
4027 * @lflags: gpio_lookup_flags - returned from of_find_gpio() or
4029 * @dflags: gpiod_flags - optional GPIO initialization flags
4031 * Return 0 on success, -ENOENT if no GPIO has been assigned to the
4032 * requested function and/or index, or another IS_ERR() code if an error
4033 * occurred while trying to acquire the GPIO.
4035 int gpiod_configure_flags(struct gpio_desc
*desc
, const char *con_id
,
4036 unsigned long lflags
, enum gpiod_flags dflags
)
4040 if (lflags
& GPIO_ACTIVE_LOW
)
4041 set_bit(FLAG_ACTIVE_LOW
, &desc
->flags
);
4043 if (lflags
& GPIO_OPEN_DRAIN
)
4044 set_bit(FLAG_OPEN_DRAIN
, &desc
->flags
);
4045 else if (dflags
& GPIOD_FLAGS_BIT_OPEN_DRAIN
) {
4047 * This enforces open drain mode from the consumer side.
4048 * This is necessary for some busses like I2C, but the lookup
4049 * should *REALLY* have specified them as open drain in the
4050 * first place, so print a little warning here.
4052 set_bit(FLAG_OPEN_DRAIN
, &desc
->flags
);
4054 "enforced open drain please flag it properly in DT/ACPI DSDT/board file\n");
4057 if (lflags
& GPIO_OPEN_SOURCE
)
4058 set_bit(FLAG_OPEN_SOURCE
, &desc
->flags
);
4060 status
= gpiod_set_transitory(desc
, (lflags
& GPIO_TRANSITORY
));
4064 /* No particular flag request, return here... */
4065 if (!(dflags
& GPIOD_FLAGS_BIT_DIR_SET
)) {
4066 pr_debug("no flags found for %s\n", con_id
);
4071 if (dflags
& GPIOD_FLAGS_BIT_DIR_OUT
)
4072 status
= gpiod_direction_output(desc
,
4073 !!(dflags
& GPIOD_FLAGS_BIT_DIR_VAL
));
4075 status
= gpiod_direction_input(desc
);
4081 * gpiod_get_index - obtain a GPIO from a multi-index GPIO function
4082 * @dev: GPIO consumer, can be NULL for system-global GPIOs
4083 * @con_id: function within the GPIO consumer
4084 * @idx: index of the GPIO to obtain in the consumer
4085 * @flags: optional GPIO initialization flags
4087 * This variant of gpiod_get() allows to access GPIOs other than the first
4088 * defined one for functions that define several GPIOs.
4090 * Return a valid GPIO descriptor, -ENOENT if no GPIO has been assigned to the
4091 * requested function and/or index, or another IS_ERR() code if an error
4092 * occurred while trying to acquire the GPIO.
4094 struct gpio_desc
*__must_check
gpiod_get_index(struct device
*dev
,
4097 enum gpiod_flags flags
)
4099 struct gpio_desc
*desc
= NULL
;
4101 enum gpio_lookup_flags lookupflags
= 0;
4102 /* Maybe we have a device name, maybe not */
4103 const char *devname
= dev
? dev_name(dev
) : "?";
4105 dev_dbg(dev
, "GPIO lookup for consumer %s\n", con_id
);
4108 /* Using device tree? */
4109 if (IS_ENABLED(CONFIG_OF
) && dev
->of_node
) {
4110 dev_dbg(dev
, "using device tree for GPIO lookup\n");
4111 desc
= of_find_gpio(dev
, con_id
, idx
, &lookupflags
);
4112 } else if (ACPI_COMPANION(dev
)) {
4113 dev_dbg(dev
, "using ACPI for GPIO lookup\n");
4114 desc
= acpi_find_gpio(dev
, con_id
, idx
, &flags
, &lookupflags
);
4119 * Either we are not using DT or ACPI, or their lookup did not return
4120 * a result. In that case, use platform lookup as a fallback.
4122 if (!desc
|| desc
== ERR_PTR(-ENOENT
)) {
4123 dev_dbg(dev
, "using lookup tables for GPIO lookup\n");
4124 desc
= gpiod_find(dev
, con_id
, idx
, &lookupflags
);
4128 dev_dbg(dev
, "No GPIO consumer %s found\n", con_id
);
4133 * If a connection label was passed use that, else attempt to use
4134 * the device name as label
4136 status
= gpiod_request(desc
, con_id
? con_id
: devname
);
4138 if (status
== -EBUSY
&& flags
& GPIOD_FLAGS_BIT_NONEXCLUSIVE
) {
4140 * This happens when there are several consumers for
4141 * the same GPIO line: we just return here without
4142 * further initialization. It is a bit if a hack.
4143 * This is necessary to support fixed regulators.
4145 * FIXME: Make this more sane and safe.
4147 dev_info(dev
, "nonexclusive access to GPIO for %s\n",
4148 con_id
? con_id
: devname
);
4151 return ERR_PTR(status
);
4155 status
= gpiod_configure_flags(desc
, con_id
, lookupflags
, flags
);
4157 dev_dbg(dev
, "setup of GPIO %s failed\n", con_id
);
4159 return ERR_PTR(status
);
4164 EXPORT_SYMBOL_GPL(gpiod_get_index
);
4167 * gpiod_get_from_of_node() - obtain a GPIO from an OF node
4168 * @node: handle of the OF node
4169 * @propname: name of the DT property representing the GPIO
4170 * @index: index of the GPIO to obtain for the consumer
4171 * @dflags: GPIO initialization flags
4172 * @label: label to attach to the requested GPIO
4175 * On successful request the GPIO pin is configured in accordance with
4176 * provided @dflags. If the node does not have the requested GPIO
4177 * property, NULL is returned.
4179 * In case of error an ERR_PTR() is returned.
4181 struct gpio_desc
*gpiod_get_from_of_node(struct device_node
*node
,
4182 const char *propname
, int index
,
4183 enum gpiod_flags dflags
,
4186 struct gpio_desc
*desc
;
4187 unsigned long lflags
= 0;
4188 enum of_gpio_flags flags
;
4189 bool active_low
= false;
4190 bool single_ended
= false;
4191 bool open_drain
= false;
4192 bool transitory
= false;
4195 desc
= of_get_named_gpiod_flags(node
, propname
,
4198 if (!desc
|| IS_ERR(desc
)) {
4199 /* If it is not there, just return NULL */
4200 if (PTR_ERR(desc
) == -ENOENT
)
4205 active_low
= flags
& OF_GPIO_ACTIVE_LOW
;
4206 single_ended
= flags
& OF_GPIO_SINGLE_ENDED
;
4207 open_drain
= flags
& OF_GPIO_OPEN_DRAIN
;
4208 transitory
= flags
& OF_GPIO_TRANSITORY
;
4210 ret
= gpiod_request(desc
, label
);
4211 if (ret
== -EBUSY
&& (flags
& GPIOD_FLAGS_BIT_NONEXCLUSIVE
))
4214 return ERR_PTR(ret
);
4217 lflags
|= GPIO_ACTIVE_LOW
;
4221 lflags
|= GPIO_OPEN_DRAIN
;
4223 lflags
|= GPIO_OPEN_SOURCE
;
4227 lflags
|= GPIO_TRANSITORY
;
4229 ret
= gpiod_configure_flags(desc
, propname
, lflags
, dflags
);
4232 return ERR_PTR(ret
);
4237 EXPORT_SYMBOL(gpiod_get_from_of_node
);
4240 * fwnode_get_named_gpiod - obtain a GPIO from firmware node
4241 * @fwnode: handle of the firmware node
4242 * @propname: name of the firmware property representing the GPIO
4243 * @index: index of the GPIO to obtain for the consumer
4244 * @dflags: GPIO initialization flags
4245 * @label: label to attach to the requested GPIO
4247 * This function can be used for drivers that get their configuration
4248 * from opaque firmware.
4250 * The function properly finds the corresponding GPIO using whatever is the
4251 * underlying firmware interface and then makes sure that the GPIO
4252 * descriptor is requested before it is returned to the caller.
4255 * On successful request the GPIO pin is configured in accordance with
4258 * In case of error an ERR_PTR() is returned.
4260 struct gpio_desc
*fwnode_get_named_gpiod(struct fwnode_handle
*fwnode
,
4261 const char *propname
, int index
,
4262 enum gpiod_flags dflags
,
4265 struct gpio_desc
*desc
= ERR_PTR(-ENODEV
);
4266 unsigned long lflags
= 0;
4270 return ERR_PTR(-EINVAL
);
4272 if (is_of_node(fwnode
)) {
4273 desc
= gpiod_get_from_of_node(to_of_node(fwnode
),
4278 } else if (is_acpi_node(fwnode
)) {
4279 struct acpi_gpio_info info
;
4281 desc
= acpi_node_get_gpiod(fwnode
, propname
, index
, &info
);
4285 acpi_gpio_update_gpiod_flags(&dflags
, &info
);
4287 if (info
.polarity
== GPIO_ACTIVE_LOW
)
4288 lflags
|= GPIO_ACTIVE_LOW
;
4291 /* Currently only ACPI takes this path */
4292 ret
= gpiod_request(desc
, label
);
4294 return ERR_PTR(ret
);
4296 ret
= gpiod_configure_flags(desc
, propname
, lflags
, dflags
);
4299 return ERR_PTR(ret
);
4304 EXPORT_SYMBOL_GPL(fwnode_get_named_gpiod
);
4307 * gpiod_get_index_optional - obtain an optional GPIO from a multi-index GPIO
4309 * @dev: GPIO consumer, can be NULL for system-global GPIOs
4310 * @con_id: function within the GPIO consumer
4311 * @index: index of the GPIO to obtain in the consumer
4312 * @flags: optional GPIO initialization flags
4314 * This is equivalent to gpiod_get_index(), except that when no GPIO with the
4315 * specified index was assigned to the requested function it will return NULL.
4316 * This is convenient for drivers that need to handle optional GPIOs.
4318 struct gpio_desc
*__must_check
gpiod_get_index_optional(struct device
*dev
,
4321 enum gpiod_flags flags
)
4323 struct gpio_desc
*desc
;
4325 desc
= gpiod_get_index(dev
, con_id
, index
, flags
);
4327 if (PTR_ERR(desc
) == -ENOENT
)
4333 EXPORT_SYMBOL_GPL(gpiod_get_index_optional
);
4336 * gpiod_hog - Hog the specified GPIO desc given the provided flags
4337 * @desc: gpio whose value will be assigned
4338 * @name: gpio line name
4339 * @lflags: gpio_lookup_flags - returned from of_find_gpio() or
4341 * @dflags: gpiod_flags - optional GPIO initialization flags
4343 int gpiod_hog(struct gpio_desc
*desc
, const char *name
,
4344 unsigned long lflags
, enum gpiod_flags dflags
)
4346 struct gpio_chip
*chip
;
4347 struct gpio_desc
*local_desc
;
4351 chip
= gpiod_to_chip(desc
);
4352 hwnum
= gpio_chip_hwgpio(desc
);
4355 * FIXME: not very elegant that we call gpiod_configure_flags()
4356 * twice here (once inside gpiochip_request_own_desc() and
4357 * again here), but the gpiochip_request_own_desc() is external
4358 * and cannot really pass the lflags so this is the lesser evil
4359 * at the moment. Pass zero as dflags on this first call so we
4360 * don't screw anything up.
4362 local_desc
= gpiochip_request_own_desc(chip
, hwnum
, name
, 0);
4363 if (IS_ERR(local_desc
)) {
4364 status
= PTR_ERR(local_desc
);
4365 pr_err("requesting hog GPIO %s (chip %s, offset %d) failed, %d\n",
4366 name
, chip
->label
, hwnum
, status
);
4370 status
= gpiod_configure_flags(desc
, name
, lflags
, dflags
);
4372 pr_err("setup of hog GPIO %s (chip %s, offset %d) failed, %d\n",
4373 name
, chip
->label
, hwnum
, status
);
4374 gpiochip_free_own_desc(desc
);
4378 /* Mark GPIO as hogged so it can be identified and removed later */
4379 set_bit(FLAG_IS_HOGGED
, &desc
->flags
);
4381 pr_info("GPIO line %d (%s) hogged as %s%s\n",
4382 desc_to_gpio(desc
), name
,
4383 (dflags
&GPIOD_FLAGS_BIT_DIR_OUT
) ? "output" : "input",
4384 (dflags
&GPIOD_FLAGS_BIT_DIR_OUT
) ?
4385 (dflags
&GPIOD_FLAGS_BIT_DIR_VAL
) ? "/high" : "/low":"");
4391 * gpiochip_free_hogs - Scan gpio-controller chip and release GPIO hog
4392 * @chip: gpio chip to act on
4394 * This is only used by of_gpiochip_remove to free hogged gpios
4396 static void gpiochip_free_hogs(struct gpio_chip
*chip
)
4400 for (id
= 0; id
< chip
->ngpio
; id
++) {
4401 if (test_bit(FLAG_IS_HOGGED
, &chip
->gpiodev
->descs
[id
].flags
))
4402 gpiochip_free_own_desc(&chip
->gpiodev
->descs
[id
]);
4407 * gpiod_get_array - obtain multiple GPIOs from a multi-index GPIO function
4408 * @dev: GPIO consumer, can be NULL for system-global GPIOs
4409 * @con_id: function within the GPIO consumer
4410 * @flags: optional GPIO initialization flags
4412 * This function acquires all the GPIOs defined under a given function.
4414 * Return a struct gpio_descs containing an array of descriptors, -ENOENT if
4415 * no GPIO has been assigned to the requested function, or another IS_ERR()
4416 * code if an error occurred while trying to acquire the GPIOs.
4418 struct gpio_descs
*__must_check
gpiod_get_array(struct device
*dev
,
4420 enum gpiod_flags flags
)
4422 struct gpio_desc
*desc
;
4423 struct gpio_descs
*descs
;
4424 struct gpio_array
*array_info
= NULL
;
4425 struct gpio_chip
*chip
;
4426 int count
, bitmap_size
;
4428 count
= gpiod_count(dev
, con_id
);
4430 return ERR_PTR(count
);
4432 descs
= kzalloc(struct_size(descs
, desc
, count
), GFP_KERNEL
);
4434 return ERR_PTR(-ENOMEM
);
4436 for (descs
->ndescs
= 0; descs
->ndescs
< count
; ) {
4437 desc
= gpiod_get_index(dev
, con_id
, descs
->ndescs
, flags
);
4439 gpiod_put_array(descs
);
4440 return ERR_CAST(desc
);
4443 descs
->desc
[descs
->ndescs
] = desc
;
4445 chip
= gpiod_to_chip(desc
);
4447 * If pin hardware number of array member 0 is also 0, select
4448 * its chip as a candidate for fast bitmap processing path.
4450 if (descs
->ndescs
== 0 && gpio_chip_hwgpio(desc
) == 0) {
4451 struct gpio_descs
*array
;
4453 bitmap_size
= BITS_TO_LONGS(chip
->ngpio
> count
?
4454 chip
->ngpio
: count
);
4456 array
= kzalloc(struct_size(descs
, desc
, count
) +
4457 struct_size(array_info
, invert_mask
,
4458 3 * bitmap_size
), GFP_KERNEL
);
4460 gpiod_put_array(descs
);
4461 return ERR_PTR(-ENOMEM
);
4464 memcpy(array
, descs
,
4465 struct_size(descs
, desc
, descs
->ndescs
+ 1));
4469 array_info
= (void *)(descs
->desc
+ count
);
4470 array_info
->get_mask
= array_info
->invert_mask
+
4472 array_info
->set_mask
= array_info
->get_mask
+
4475 array_info
->desc
= descs
->desc
;
4476 array_info
->size
= count
;
4477 array_info
->chip
= chip
;
4478 bitmap_set(array_info
->get_mask
, descs
->ndescs
,
4479 count
- descs
->ndescs
);
4480 bitmap_set(array_info
->set_mask
, descs
->ndescs
,
4481 count
- descs
->ndescs
);
4482 descs
->info
= array_info
;
4484 /* Unmark array members which don't belong to the 'fast' chip */
4485 if (array_info
&& array_info
->chip
!= chip
) {
4486 __clear_bit(descs
->ndescs
, array_info
->get_mask
);
4487 __clear_bit(descs
->ndescs
, array_info
->set_mask
);
4490 * Detect array members which belong to the 'fast' chip
4491 * but their pins are not in hardware order.
4493 else if (array_info
&&
4494 gpio_chip_hwgpio(desc
) != descs
->ndescs
) {
4496 * Don't use fast path if all array members processed so
4497 * far belong to the same chip as this one but its pin
4498 * hardware number is different from its array index.
4500 if (bitmap_full(array_info
->get_mask
, descs
->ndescs
)) {
4503 __clear_bit(descs
->ndescs
,
4504 array_info
->get_mask
);
4505 __clear_bit(descs
->ndescs
,
4506 array_info
->set_mask
);
4508 } else if (array_info
) {
4509 /* Exclude open drain or open source from fast output */
4510 if (gpiochip_line_is_open_drain(chip
, descs
->ndescs
) ||
4511 gpiochip_line_is_open_source(chip
, descs
->ndescs
))
4512 __clear_bit(descs
->ndescs
,
4513 array_info
->set_mask
);
4514 /* Identify 'fast' pins which require invertion */
4515 if (gpiod_is_active_low(desc
))
4516 __set_bit(descs
->ndescs
,
4517 array_info
->invert_mask
);
4524 "GPIO array info: chip=%s, size=%d, get_mask=%lx, set_mask=%lx, invert_mask=%lx\n",
4525 array_info
->chip
->label
, array_info
->size
,
4526 *array_info
->get_mask
, *array_info
->set_mask
,
4527 *array_info
->invert_mask
);
4530 EXPORT_SYMBOL_GPL(gpiod_get_array
);
4533 * gpiod_get_array_optional - obtain multiple GPIOs from a multi-index GPIO
4535 * @dev: GPIO consumer, can be NULL for system-global GPIOs
4536 * @con_id: function within the GPIO consumer
4537 * @flags: optional GPIO initialization flags
4539 * This is equivalent to gpiod_get_array(), except that when no GPIO was
4540 * assigned to the requested function it will return NULL.
4542 struct gpio_descs
*__must_check
gpiod_get_array_optional(struct device
*dev
,
4544 enum gpiod_flags flags
)
4546 struct gpio_descs
*descs
;
4548 descs
= gpiod_get_array(dev
, con_id
, flags
);
4549 if (IS_ERR(descs
) && (PTR_ERR(descs
) == -ENOENT
))
4554 EXPORT_SYMBOL_GPL(gpiod_get_array_optional
);
4557 * gpiod_put - dispose of a GPIO descriptor
4558 * @desc: GPIO descriptor to dispose of
4560 * No descriptor can be used after gpiod_put() has been called on it.
4562 void gpiod_put(struct gpio_desc
*desc
)
4566 EXPORT_SYMBOL_GPL(gpiod_put
);
4569 * gpiod_put_array - dispose of multiple GPIO descriptors
4570 * @descs: struct gpio_descs containing an array of descriptors
4572 void gpiod_put_array(struct gpio_descs
*descs
)
4576 for (i
= 0; i
< descs
->ndescs
; i
++)
4577 gpiod_put(descs
->desc
[i
]);
4581 EXPORT_SYMBOL_GPL(gpiod_put_array
);
4583 static int __init
gpiolib_dev_init(void)
4587 /* Register GPIO sysfs bus */
4588 ret
= bus_register(&gpio_bus_type
);
4590 pr_err("gpiolib: could not register GPIO bus type\n");
4594 ret
= alloc_chrdev_region(&gpio_devt
, 0, GPIO_DEV_MAX
, "gpiochip");
4596 pr_err("gpiolib: failed to allocate char dev region\n");
4597 bus_unregister(&gpio_bus_type
);
4599 gpiolib_initialized
= true;
4600 gpiochip_setup_devs();
4604 core_initcall(gpiolib_dev_init
);
4606 #ifdef CONFIG_DEBUG_FS
4608 static void gpiolib_dbg_show(struct seq_file
*s
, struct gpio_device
*gdev
)
4611 struct gpio_chip
*chip
= gdev
->chip
;
4612 unsigned gpio
= gdev
->base
;
4613 struct gpio_desc
*gdesc
= &gdev
->descs
[0];
4618 for (i
= 0; i
< gdev
->ngpio
; i
++, gpio
++, gdesc
++) {
4619 if (!test_bit(FLAG_REQUESTED
, &gdesc
->flags
)) {
4621 seq_printf(s
, " gpio-%-3d (%-20.20s)\n",
4627 gpiod_get_direction(gdesc
);
4628 is_out
= test_bit(FLAG_IS_OUT
, &gdesc
->flags
);
4629 is_irq
= test_bit(FLAG_USED_AS_IRQ
, &gdesc
->flags
);
4630 active_low
= test_bit(FLAG_ACTIVE_LOW
, &gdesc
->flags
);
4631 seq_printf(s
, " gpio-%-3d (%-20.20s|%-20.20s) %s %s %s%s",
4632 gpio
, gdesc
->name
? gdesc
->name
: "", gdesc
->label
,
4633 is_out
? "out" : "in ",
4634 chip
->get
? (chip
->get(chip
, i
) ? "hi" : "lo") : "? ",
4635 is_irq
? "IRQ " : "",
4636 active_low
? "ACTIVE LOW" : "");
4637 seq_printf(s
, "\n");
4641 static void *gpiolib_seq_start(struct seq_file
*s
, loff_t
*pos
)
4643 unsigned long flags
;
4644 struct gpio_device
*gdev
= NULL
;
4645 loff_t index
= *pos
;
4649 spin_lock_irqsave(&gpio_lock
, flags
);
4650 list_for_each_entry(gdev
, &gpio_devices
, list
)
4652 spin_unlock_irqrestore(&gpio_lock
, flags
);
4655 spin_unlock_irqrestore(&gpio_lock
, flags
);
4660 static void *gpiolib_seq_next(struct seq_file
*s
, void *v
, loff_t
*pos
)
4662 unsigned long flags
;
4663 struct gpio_device
*gdev
= v
;
4666 spin_lock_irqsave(&gpio_lock
, flags
);
4667 if (list_is_last(&gdev
->list
, &gpio_devices
))
4670 ret
= list_entry(gdev
->list
.next
, struct gpio_device
, list
);
4671 spin_unlock_irqrestore(&gpio_lock
, flags
);
4679 static void gpiolib_seq_stop(struct seq_file
*s
, void *v
)
4683 static int gpiolib_seq_show(struct seq_file
*s
, void *v
)
4685 struct gpio_device
*gdev
= v
;
4686 struct gpio_chip
*chip
= gdev
->chip
;
4687 struct device
*parent
;
4690 seq_printf(s
, "%s%s: (dangling chip)", (char *)s
->private,
4691 dev_name(&gdev
->dev
));
4695 seq_printf(s
, "%s%s: GPIOs %d-%d", (char *)s
->private,
4696 dev_name(&gdev
->dev
),
4697 gdev
->base
, gdev
->base
+ gdev
->ngpio
- 1);
4698 parent
= chip
->parent
;
4700 seq_printf(s
, ", parent: %s/%s",
4701 parent
->bus
? parent
->bus
->name
: "no-bus",
4704 seq_printf(s
, ", %s", chip
->label
);
4705 if (chip
->can_sleep
)
4706 seq_printf(s
, ", can sleep");
4707 seq_printf(s
, ":\n");
4710 chip
->dbg_show(s
, chip
);
4712 gpiolib_dbg_show(s
, gdev
);
4717 static const struct seq_operations gpiolib_seq_ops
= {
4718 .start
= gpiolib_seq_start
,
4719 .next
= gpiolib_seq_next
,
4720 .stop
= gpiolib_seq_stop
,
4721 .show
= gpiolib_seq_show
,
4724 static int gpiolib_open(struct inode
*inode
, struct file
*file
)
4726 return seq_open(file
, &gpiolib_seq_ops
);
4729 static const struct file_operations gpiolib_operations
= {
4730 .owner
= THIS_MODULE
,
4731 .open
= gpiolib_open
,
4733 .llseek
= seq_lseek
,
4734 .release
= seq_release
,
4737 static int __init
gpiolib_debugfs_init(void)
4739 /* /sys/kernel/debug/gpio */
4740 (void) debugfs_create_file("gpio", S_IFREG
| S_IRUGO
,
4741 NULL
, NULL
, &gpiolib_operations
);
4744 subsys_initcall(gpiolib_debugfs_init
);
4746 #endif /* DEBUG_FS */