1 #include <linux/bitmap.h>
2 #include <linux/kernel.h>
3 #include <linux/module.h>
4 #include <linux/interrupt.h>
6 #include <linux/spinlock.h>
7 #include <linux/list.h>
8 #include <linux/device.h>
10 #include <linux/debugfs.h>
11 #include <linux/seq_file.h>
12 #include <linux/gpio.h>
13 #include <linux/of_gpio.h>
14 #include <linux/idr.h>
15 #include <linux/slab.h>
16 #include <linux/acpi.h>
17 #include <linux/gpio/driver.h>
18 #include <linux/gpio/machine.h>
19 #include <linux/pinctrl/consumer.h>
20 #include <linux/cdev.h>
22 #include <linux/uaccess.h>
23 #include <linux/compat.h>
24 #include <linux/anon_inodes.h>
25 #include <linux/file.h>
26 #include <linux/kfifo.h>
27 #include <linux/poll.h>
28 #include <linux/timekeeping.h>
29 #include <uapi/linux/gpio.h>
33 #define CREATE_TRACE_POINTS
34 #include <trace/events/gpio.h>
36 /* Implementation infrastructure for GPIO interfaces.
38 * The GPIO programming interface allows for inlining speed-critical
39 * get/set operations for common cases, so that access to SOC-integrated
40 * GPIOs can sometimes cost only an instruction or two per bit.
44 /* When debugging, extend minimal trust to callers and platform code.
45 * Also emit diagnostic messages that may help initial bringup, when
46 * board setup or driver bugs are most common.
48 * Otherwise, minimize overhead in what may be bitbanging codepaths.
51 #define extra_checks 1
53 #define extra_checks 0
56 /* Device and char device-related information */
57 static DEFINE_IDA(gpio_ida
);
58 static dev_t gpio_devt
;
59 #define GPIO_DEV_MAX 256 /* 256 GPIO chip devices supported */
60 static struct bus_type gpio_bus_type
= {
64 /* gpio_lock prevents conflicts during gpio_desc[] table updates.
65 * While any GPIO is requested, its gpio_chip is not removable;
66 * each GPIO's "requested" flag serves as a lock and refcount.
68 DEFINE_SPINLOCK(gpio_lock
);
70 static DEFINE_MUTEX(gpio_lookup_lock
);
71 static LIST_HEAD(gpio_lookup_list
);
72 LIST_HEAD(gpio_devices
);
74 static void gpiochip_free_hogs(struct gpio_chip
*chip
);
75 static int gpiochip_add_irqchip(struct gpio_chip
*gpiochip
,
76 struct lock_class_key
*lock_key
,
77 struct lock_class_key
*request_key
);
78 static void gpiochip_irqchip_remove(struct gpio_chip
*gpiochip
);
79 static int gpiochip_irqchip_init_valid_mask(struct gpio_chip
*gpiochip
);
80 static void gpiochip_irqchip_free_valid_mask(struct gpio_chip
*gpiochip
);
82 static bool gpiolib_initialized
;
84 static inline void desc_set_label(struct gpio_desc
*d
, const char *label
)
90 * gpio_to_desc - Convert a GPIO number to its descriptor
91 * @gpio: global GPIO number
94 * The GPIO descriptor associated with the given GPIO, or %NULL if no GPIO
95 * with the given number exists in the system.
97 struct gpio_desc
*gpio_to_desc(unsigned gpio
)
99 struct gpio_device
*gdev
;
102 spin_lock_irqsave(&gpio_lock
, flags
);
104 list_for_each_entry(gdev
, &gpio_devices
, list
) {
105 if (gdev
->base
<= gpio
&&
106 gdev
->base
+ gdev
->ngpio
> gpio
) {
107 spin_unlock_irqrestore(&gpio_lock
, flags
);
108 return &gdev
->descs
[gpio
- gdev
->base
];
112 spin_unlock_irqrestore(&gpio_lock
, flags
);
114 if (!gpio_is_valid(gpio
))
115 WARN(1, "invalid GPIO %d\n", gpio
);
119 EXPORT_SYMBOL_GPL(gpio_to_desc
);
122 * gpiochip_get_desc - get the GPIO descriptor corresponding to the given
123 * hardware number for this chip
125 * @hwnum: hardware number of the GPIO for this chip
128 * A pointer to the GPIO descriptor or %ERR_PTR(-EINVAL) if no GPIO exists
129 * in the given chip for the specified hardware number.
131 struct gpio_desc
*gpiochip_get_desc(struct gpio_chip
*chip
,
134 struct gpio_device
*gdev
= chip
->gpiodev
;
136 if (hwnum
>= gdev
->ngpio
)
137 return ERR_PTR(-EINVAL
);
139 return &gdev
->descs
[hwnum
];
143 * desc_to_gpio - convert a GPIO descriptor to the integer namespace
144 * @desc: GPIO descriptor
146 * This should disappear in the future but is needed since we still
147 * use GPIO numbers for error messages and sysfs nodes.
150 * The global GPIO number for the GPIO specified by its descriptor.
152 int desc_to_gpio(const struct gpio_desc
*desc
)
154 return desc
->gdev
->base
+ (desc
- &desc
->gdev
->descs
[0]);
156 EXPORT_SYMBOL_GPL(desc_to_gpio
);
160 * gpiod_to_chip - Return the GPIO chip to which a GPIO descriptor belongs
161 * @desc: descriptor to return the chip of
163 struct gpio_chip
*gpiod_to_chip(const struct gpio_desc
*desc
)
165 if (!desc
|| !desc
->gdev
|| !desc
->gdev
->chip
)
167 return desc
->gdev
->chip
;
169 EXPORT_SYMBOL_GPL(gpiod_to_chip
);
171 /* dynamic allocation of GPIOs, e.g. on a hotplugged device */
172 static int gpiochip_find_base(int ngpio
)
174 struct gpio_device
*gdev
;
175 int base
= ARCH_NR_GPIOS
- ngpio
;
177 list_for_each_entry_reverse(gdev
, &gpio_devices
, list
) {
178 /* found a free space? */
179 if (gdev
->base
+ gdev
->ngpio
<= base
)
182 /* nope, check the space right before the chip */
183 base
= gdev
->base
- ngpio
;
186 if (gpio_is_valid(base
)) {
187 pr_debug("%s: found new base at %d\n", __func__
, base
);
190 pr_err("%s: cannot find free range\n", __func__
);
196 * gpiod_get_direction - return the current direction of a GPIO
197 * @desc: GPIO to get the direction of
199 * Return GPIOF_DIR_IN or GPIOF_DIR_OUT, or an error code in case of error.
201 * This function may sleep if gpiod_cansleep() is true.
203 int gpiod_get_direction(struct gpio_desc
*desc
)
205 struct gpio_chip
*chip
;
207 int status
= -EINVAL
;
209 chip
= gpiod_to_chip(desc
);
210 offset
= gpio_chip_hwgpio(desc
);
212 if (!chip
->get_direction
)
215 status
= chip
->get_direction(chip
, offset
);
217 /* GPIOF_DIR_IN, or other positive */
219 clear_bit(FLAG_IS_OUT
, &desc
->flags
);
223 set_bit(FLAG_IS_OUT
, &desc
->flags
);
227 EXPORT_SYMBOL_GPL(gpiod_get_direction
);
230 * Add a new chip to the global chips list, keeping the list of chips sorted
231 * by range(means [base, base + ngpio - 1]) order.
233 * Return -EBUSY if the new chip overlaps with some other chip's integer
236 static int gpiodev_add_to_list(struct gpio_device
*gdev
)
238 struct gpio_device
*prev
, *next
;
240 if (list_empty(&gpio_devices
)) {
241 /* initial entry in list */
242 list_add_tail(&gdev
->list
, &gpio_devices
);
246 next
= list_entry(gpio_devices
.next
, struct gpio_device
, list
);
247 if (gdev
->base
+ gdev
->ngpio
<= next
->base
) {
248 /* add before first entry */
249 list_add(&gdev
->list
, &gpio_devices
);
253 prev
= list_entry(gpio_devices
.prev
, struct gpio_device
, list
);
254 if (prev
->base
+ prev
->ngpio
<= gdev
->base
) {
255 /* add behind last entry */
256 list_add_tail(&gdev
->list
, &gpio_devices
);
260 list_for_each_entry_safe(prev
, next
, &gpio_devices
, list
) {
261 /* at the end of the list */
262 if (&next
->list
== &gpio_devices
)
265 /* add between prev and next */
266 if (prev
->base
+ prev
->ngpio
<= gdev
->base
267 && gdev
->base
+ gdev
->ngpio
<= next
->base
) {
268 list_add(&gdev
->list
, &prev
->list
);
273 dev_err(&gdev
->dev
, "GPIO integer space overlap, cannot add chip\n");
278 * Convert a GPIO name to its descriptor
280 static struct gpio_desc
*gpio_name_to_desc(const char * const name
)
282 struct gpio_device
*gdev
;
285 spin_lock_irqsave(&gpio_lock
, flags
);
287 list_for_each_entry(gdev
, &gpio_devices
, list
) {
290 for (i
= 0; i
!= gdev
->ngpio
; ++i
) {
291 struct gpio_desc
*desc
= &gdev
->descs
[i
];
293 if (!desc
->name
|| !name
)
296 if (!strcmp(desc
->name
, name
)) {
297 spin_unlock_irqrestore(&gpio_lock
, flags
);
303 spin_unlock_irqrestore(&gpio_lock
, flags
);
309 * Takes the names from gc->names and checks if they are all unique. If they
310 * are, they are assigned to their gpio descriptors.
312 * Warning if one of the names is already used for a different GPIO.
314 static int gpiochip_set_desc_names(struct gpio_chip
*gc
)
316 struct gpio_device
*gdev
= gc
->gpiodev
;
322 /* First check all names if they are unique */
323 for (i
= 0; i
!= gc
->ngpio
; ++i
) {
324 struct gpio_desc
*gpio
;
326 gpio
= gpio_name_to_desc(gc
->names
[i
]);
329 "Detected name collision for GPIO name '%s'\n",
333 /* Then add all names to the GPIO descriptors */
334 for (i
= 0; i
!= gc
->ngpio
; ++i
)
335 gdev
->descs
[i
].name
= gc
->names
[i
];
341 * GPIO line handle management
345 * struct linehandle_state - contains the state of a userspace handle
346 * @gdev: the GPIO device the handle pertains to
347 * @label: consumer label used to tag descriptors
348 * @descs: the GPIO descriptors held by this handle
349 * @numdescs: the number of descriptors held in the descs array
351 struct linehandle_state
{
352 struct gpio_device
*gdev
;
354 struct gpio_desc
*descs
[GPIOHANDLES_MAX
];
358 #define GPIOHANDLE_REQUEST_VALID_FLAGS \
359 (GPIOHANDLE_REQUEST_INPUT | \
360 GPIOHANDLE_REQUEST_OUTPUT | \
361 GPIOHANDLE_REQUEST_ACTIVE_LOW | \
362 GPIOHANDLE_REQUEST_OPEN_DRAIN | \
363 GPIOHANDLE_REQUEST_OPEN_SOURCE)
365 static long linehandle_ioctl(struct file
*filep
, unsigned int cmd
,
368 struct linehandle_state
*lh
= filep
->private_data
;
369 void __user
*ip
= (void __user
*)arg
;
370 struct gpiohandle_data ghd
;
371 int vals
[GPIOHANDLES_MAX
];
374 if (cmd
== GPIOHANDLE_GET_LINE_VALUES_IOCTL
) {
375 /* TODO: check if descriptors are really input */
376 int ret
= gpiod_get_array_value_complex(false,
384 memset(&ghd
, 0, sizeof(ghd
));
385 for (i
= 0; i
< lh
->numdescs
; i
++)
386 ghd
.values
[i
] = vals
[i
];
388 if (copy_to_user(ip
, &ghd
, sizeof(ghd
)))
392 } else if (cmd
== GPIOHANDLE_SET_LINE_VALUES_IOCTL
) {
393 /* TODO: check if descriptors are really output */
394 if (copy_from_user(&ghd
, ip
, sizeof(ghd
)))
397 /* Clamp all values to [0,1] */
398 for (i
= 0; i
< lh
->numdescs
; i
++)
399 vals
[i
] = !!ghd
.values
[i
];
401 /* Reuse the array setting function */
402 gpiod_set_array_value_complex(false,
413 static long linehandle_ioctl_compat(struct file
*filep
, unsigned int cmd
,
416 return linehandle_ioctl(filep
, cmd
, (unsigned long)compat_ptr(arg
));
420 static int linehandle_release(struct inode
*inode
, struct file
*filep
)
422 struct linehandle_state
*lh
= filep
->private_data
;
423 struct gpio_device
*gdev
= lh
->gdev
;
426 for (i
= 0; i
< lh
->numdescs
; i
++)
427 gpiod_free(lh
->descs
[i
]);
430 put_device(&gdev
->dev
);
434 static const struct file_operations linehandle_fileops
= {
435 .release
= linehandle_release
,
436 .owner
= THIS_MODULE
,
437 .llseek
= noop_llseek
,
438 .unlocked_ioctl
= linehandle_ioctl
,
440 .compat_ioctl
= linehandle_ioctl_compat
,
444 static int linehandle_create(struct gpio_device
*gdev
, void __user
*ip
)
446 struct gpiohandle_request handlereq
;
447 struct linehandle_state
*lh
;
452 if (copy_from_user(&handlereq
, ip
, sizeof(handlereq
)))
454 if ((handlereq
.lines
== 0) || (handlereq
.lines
> GPIOHANDLES_MAX
))
457 lflags
= handlereq
.flags
;
459 /* Return an error if an unknown flag is set */
460 if (lflags
& ~GPIOHANDLE_REQUEST_VALID_FLAGS
)
463 /* OPEN_DRAIN and OPEN_SOURCE flags only make sense for output mode. */
464 if (!(lflags
& GPIOHANDLE_REQUEST_OUTPUT
) &&
465 ((lflags
& GPIOHANDLE_REQUEST_OPEN_DRAIN
) ||
466 (lflags
& GPIOHANDLE_REQUEST_OPEN_SOURCE
)))
469 lh
= kzalloc(sizeof(*lh
), GFP_KERNEL
);
473 get_device(&gdev
->dev
);
475 /* Make sure this is terminated */
476 handlereq
.consumer_label
[sizeof(handlereq
.consumer_label
)-1] = '\0';
477 if (strlen(handlereq
.consumer_label
)) {
478 lh
->label
= kstrdup(handlereq
.consumer_label
,
486 /* Request each GPIO */
487 for (i
= 0; i
< handlereq
.lines
; i
++) {
488 u32 offset
= handlereq
.lineoffsets
[i
];
489 struct gpio_desc
*desc
;
491 if (offset
>= gdev
->ngpio
) {
496 desc
= &gdev
->descs
[offset
];
497 ret
= gpiod_request(desc
, lh
->label
);
502 if (lflags
& GPIOHANDLE_REQUEST_ACTIVE_LOW
)
503 set_bit(FLAG_ACTIVE_LOW
, &desc
->flags
);
504 if (lflags
& GPIOHANDLE_REQUEST_OPEN_DRAIN
)
505 set_bit(FLAG_OPEN_DRAIN
, &desc
->flags
);
506 if (lflags
& GPIOHANDLE_REQUEST_OPEN_SOURCE
)
507 set_bit(FLAG_OPEN_SOURCE
, &desc
->flags
);
510 * Lines have to be requested explicitly for input
511 * or output, else the line will be treated "as is".
513 if (lflags
& GPIOHANDLE_REQUEST_OUTPUT
) {
514 int val
= !!handlereq
.default_values
[i
];
516 ret
= gpiod_direction_output(desc
, val
);
519 } else if (lflags
& GPIOHANDLE_REQUEST_INPUT
) {
520 ret
= gpiod_direction_input(desc
);
524 dev_dbg(&gdev
->dev
, "registered chardev handle for line %d\n",
527 /* Let i point at the last handle */
529 lh
->numdescs
= handlereq
.lines
;
531 fd
= get_unused_fd_flags(O_RDONLY
| O_CLOEXEC
);
537 file
= anon_inode_getfile("gpio-linehandle",
540 O_RDONLY
| O_CLOEXEC
);
543 goto out_put_unused_fd
;
547 if (copy_to_user(ip
, &handlereq
, sizeof(handlereq
))) {
549 * fput() will trigger the release() callback, so do not go onto
550 * the regular error cleanup path here.
557 fd_install(fd
, file
);
559 dev_dbg(&gdev
->dev
, "registered chardev handle for %d lines\n",
568 gpiod_free(lh
->descs
[i
]);
572 put_device(&gdev
->dev
);
577 * GPIO line event management
581 * struct lineevent_state - contains the state of a userspace event
582 * @gdev: the GPIO device the event pertains to
583 * @label: consumer label used to tag descriptors
584 * @desc: the GPIO descriptor held by this event
585 * @eflags: the event flags this line was requested with
586 * @irq: the interrupt that trigger in response to events on this GPIO
587 * @wait: wait queue that handles blocking reads of events
588 * @events: KFIFO for the GPIO events
589 * @read_lock: mutex lock to protect reads from colliding with adding
590 * new events to the FIFO
592 struct lineevent_state
{
593 struct gpio_device
*gdev
;
595 struct gpio_desc
*desc
;
598 wait_queue_head_t wait
;
599 DECLARE_KFIFO(events
, struct gpioevent_data
, 16);
600 struct mutex read_lock
;
603 #define GPIOEVENT_REQUEST_VALID_FLAGS \
604 (GPIOEVENT_REQUEST_RISING_EDGE | \
605 GPIOEVENT_REQUEST_FALLING_EDGE)
607 static unsigned int lineevent_poll(struct file
*filep
,
608 struct poll_table_struct
*wait
)
610 struct lineevent_state
*le
= filep
->private_data
;
611 unsigned int events
= 0;
613 poll_wait(filep
, &le
->wait
, wait
);
615 if (!kfifo_is_empty(&le
->events
))
616 events
= POLLIN
| POLLRDNORM
;
622 static ssize_t
lineevent_read(struct file
*filep
,
627 struct lineevent_state
*le
= filep
->private_data
;
631 if (count
< sizeof(struct gpioevent_data
))
635 if (kfifo_is_empty(&le
->events
)) {
636 if (filep
->f_flags
& O_NONBLOCK
)
639 ret
= wait_event_interruptible(le
->wait
,
640 !kfifo_is_empty(&le
->events
));
645 if (mutex_lock_interruptible(&le
->read_lock
))
647 ret
= kfifo_to_user(&le
->events
, buf
, count
, &copied
);
648 mutex_unlock(&le
->read_lock
);
654 * If we couldn't read anything from the fifo (a different
655 * thread might have been faster) we either return -EAGAIN if
656 * the file descriptor is non-blocking, otherwise we go back to
657 * sleep and wait for more data to arrive.
659 if (copied
== 0 && (filep
->f_flags
& O_NONBLOCK
))
662 } while (copied
== 0);
667 static int lineevent_release(struct inode
*inode
, struct file
*filep
)
669 struct lineevent_state
*le
= filep
->private_data
;
670 struct gpio_device
*gdev
= le
->gdev
;
672 free_irq(le
->irq
, le
);
673 gpiod_free(le
->desc
);
676 put_device(&gdev
->dev
);
680 static long lineevent_ioctl(struct file
*filep
, unsigned int cmd
,
683 struct lineevent_state
*le
= filep
->private_data
;
684 void __user
*ip
= (void __user
*)arg
;
685 struct gpiohandle_data ghd
;
688 * We can get the value for an event line but not set it,
689 * because it is input by definition.
691 if (cmd
== GPIOHANDLE_GET_LINE_VALUES_IOCTL
) {
694 memset(&ghd
, 0, sizeof(ghd
));
696 val
= gpiod_get_value_cansleep(le
->desc
);
701 if (copy_to_user(ip
, &ghd
, sizeof(ghd
)))
710 static long lineevent_ioctl_compat(struct file
*filep
, unsigned int cmd
,
713 return lineevent_ioctl(filep
, cmd
, (unsigned long)compat_ptr(arg
));
717 static const struct file_operations lineevent_fileops
= {
718 .release
= lineevent_release
,
719 .read
= lineevent_read
,
720 .poll
= lineevent_poll
,
721 .owner
= THIS_MODULE
,
722 .llseek
= noop_llseek
,
723 .unlocked_ioctl
= lineevent_ioctl
,
725 .compat_ioctl
= lineevent_ioctl_compat
,
729 static irqreturn_t
lineevent_irq_thread(int irq
, void *p
)
731 struct lineevent_state
*le
= p
;
732 struct gpioevent_data ge
;
735 ge
.timestamp
= ktime_get_real_ns();
736 level
= gpiod_get_value_cansleep(le
->desc
);
738 if (le
->eflags
& GPIOEVENT_REQUEST_RISING_EDGE
739 && le
->eflags
& GPIOEVENT_REQUEST_FALLING_EDGE
) {
741 /* Emit low-to-high event */
742 ge
.id
= GPIOEVENT_EVENT_RISING_EDGE
;
744 /* Emit high-to-low event */
745 ge
.id
= GPIOEVENT_EVENT_FALLING_EDGE
;
746 } else if (le
->eflags
& GPIOEVENT_REQUEST_RISING_EDGE
&& level
) {
747 /* Emit low-to-high event */
748 ge
.id
= GPIOEVENT_EVENT_RISING_EDGE
;
749 } else if (le
->eflags
& GPIOEVENT_REQUEST_FALLING_EDGE
&& !level
) {
750 /* Emit high-to-low event */
751 ge
.id
= GPIOEVENT_EVENT_FALLING_EDGE
;
756 ret
= kfifo_put(&le
->events
, ge
);
758 wake_up_poll(&le
->wait
, POLLIN
);
763 static int lineevent_create(struct gpio_device
*gdev
, void __user
*ip
)
765 struct gpioevent_request eventreq
;
766 struct lineevent_state
*le
;
767 struct gpio_desc
*desc
;
776 if (copy_from_user(&eventreq
, ip
, sizeof(eventreq
)))
779 le
= kzalloc(sizeof(*le
), GFP_KERNEL
);
783 get_device(&gdev
->dev
);
785 /* Make sure this is terminated */
786 eventreq
.consumer_label
[sizeof(eventreq
.consumer_label
)-1] = '\0';
787 if (strlen(eventreq
.consumer_label
)) {
788 le
->label
= kstrdup(eventreq
.consumer_label
,
796 offset
= eventreq
.lineoffset
;
797 lflags
= eventreq
.handleflags
;
798 eflags
= eventreq
.eventflags
;
800 if (offset
>= gdev
->ngpio
) {
805 /* Return an error if a unknown flag is set */
806 if ((lflags
& ~GPIOHANDLE_REQUEST_VALID_FLAGS
) ||
807 (eflags
& ~GPIOEVENT_REQUEST_VALID_FLAGS
)) {
812 /* This is just wrong: we don't look for events on output lines */
813 if (lflags
& GPIOHANDLE_REQUEST_OUTPUT
) {
818 desc
= &gdev
->descs
[offset
];
819 ret
= gpiod_request(desc
, le
->label
);
825 if (lflags
& GPIOHANDLE_REQUEST_ACTIVE_LOW
)
826 set_bit(FLAG_ACTIVE_LOW
, &desc
->flags
);
827 if (lflags
& GPIOHANDLE_REQUEST_OPEN_DRAIN
)
828 set_bit(FLAG_OPEN_DRAIN
, &desc
->flags
);
829 if (lflags
& GPIOHANDLE_REQUEST_OPEN_SOURCE
)
830 set_bit(FLAG_OPEN_SOURCE
, &desc
->flags
);
832 ret
= gpiod_direction_input(desc
);
836 le
->irq
= gpiod_to_irq(desc
);
842 if (eflags
& GPIOEVENT_REQUEST_RISING_EDGE
)
843 irqflags
|= IRQF_TRIGGER_RISING
;
844 if (eflags
& GPIOEVENT_REQUEST_FALLING_EDGE
)
845 irqflags
|= IRQF_TRIGGER_FALLING
;
846 irqflags
|= IRQF_ONESHOT
;
847 irqflags
|= IRQF_SHARED
;
849 INIT_KFIFO(le
->events
);
850 init_waitqueue_head(&le
->wait
);
851 mutex_init(&le
->read_lock
);
853 /* Request a thread to read the events */
854 ret
= request_threaded_irq(le
->irq
,
856 lineevent_irq_thread
,
863 fd
= get_unused_fd_flags(O_RDONLY
| O_CLOEXEC
);
869 file
= anon_inode_getfile("gpio-event",
872 O_RDONLY
| O_CLOEXEC
);
875 goto out_put_unused_fd
;
879 if (copy_to_user(ip
, &eventreq
, sizeof(eventreq
))) {
881 * fput() will trigger the release() callback, so do not go onto
882 * the regular error cleanup path here.
889 fd_install(fd
, file
);
896 free_irq(le
->irq
, le
);
898 gpiod_free(le
->desc
);
903 put_device(&gdev
->dev
);
908 * gpio_ioctl() - ioctl handler for the GPIO chardev
910 static long gpio_ioctl(struct file
*filp
, unsigned int cmd
, unsigned long arg
)
912 struct gpio_device
*gdev
= filp
->private_data
;
913 struct gpio_chip
*chip
= gdev
->chip
;
914 void __user
*ip
= (void __user
*)arg
;
916 /* We fail any subsequent ioctl():s when the chip is gone */
920 /* Fill in the struct and pass to userspace */
921 if (cmd
== GPIO_GET_CHIPINFO_IOCTL
) {
922 struct gpiochip_info chipinfo
;
924 memset(&chipinfo
, 0, sizeof(chipinfo
));
926 strncpy(chipinfo
.name
, dev_name(&gdev
->dev
),
927 sizeof(chipinfo
.name
));
928 chipinfo
.name
[sizeof(chipinfo
.name
)-1] = '\0';
929 strncpy(chipinfo
.label
, gdev
->label
,
930 sizeof(chipinfo
.label
));
931 chipinfo
.label
[sizeof(chipinfo
.label
)-1] = '\0';
932 chipinfo
.lines
= gdev
->ngpio
;
933 if (copy_to_user(ip
, &chipinfo
, sizeof(chipinfo
)))
936 } else if (cmd
== GPIO_GET_LINEINFO_IOCTL
) {
937 struct gpioline_info lineinfo
;
938 struct gpio_desc
*desc
;
940 if (copy_from_user(&lineinfo
, ip
, sizeof(lineinfo
)))
942 if (lineinfo
.line_offset
>= gdev
->ngpio
)
945 desc
= &gdev
->descs
[lineinfo
.line_offset
];
947 strncpy(lineinfo
.name
, desc
->name
,
948 sizeof(lineinfo
.name
));
949 lineinfo
.name
[sizeof(lineinfo
.name
)-1] = '\0';
951 lineinfo
.name
[0] = '\0';
954 strncpy(lineinfo
.consumer
, desc
->label
,
955 sizeof(lineinfo
.consumer
));
956 lineinfo
.consumer
[sizeof(lineinfo
.consumer
)-1] = '\0';
958 lineinfo
.consumer
[0] = '\0';
962 * Userspace only need to know that the kernel is using
963 * this GPIO so it can't use it.
966 if (test_bit(FLAG_REQUESTED
, &desc
->flags
) ||
967 test_bit(FLAG_IS_HOGGED
, &desc
->flags
) ||
968 test_bit(FLAG_USED_AS_IRQ
, &desc
->flags
) ||
969 test_bit(FLAG_EXPORT
, &desc
->flags
) ||
970 test_bit(FLAG_SYSFS
, &desc
->flags
))
971 lineinfo
.flags
|= GPIOLINE_FLAG_KERNEL
;
972 if (test_bit(FLAG_IS_OUT
, &desc
->flags
))
973 lineinfo
.flags
|= GPIOLINE_FLAG_IS_OUT
;
974 if (test_bit(FLAG_ACTIVE_LOW
, &desc
->flags
))
975 lineinfo
.flags
|= GPIOLINE_FLAG_ACTIVE_LOW
;
976 if (test_bit(FLAG_OPEN_DRAIN
, &desc
->flags
))
977 lineinfo
.flags
|= GPIOLINE_FLAG_OPEN_DRAIN
;
978 if (test_bit(FLAG_OPEN_SOURCE
, &desc
->flags
))
979 lineinfo
.flags
|= GPIOLINE_FLAG_OPEN_SOURCE
;
981 if (copy_to_user(ip
, &lineinfo
, sizeof(lineinfo
)))
984 } else if (cmd
== GPIO_GET_LINEHANDLE_IOCTL
) {
985 return linehandle_create(gdev
, ip
);
986 } else if (cmd
== GPIO_GET_LINEEVENT_IOCTL
) {
987 return lineevent_create(gdev
, ip
);
993 static long gpio_ioctl_compat(struct file
*filp
, unsigned int cmd
,
996 return gpio_ioctl(filp
, cmd
, (unsigned long)compat_ptr(arg
));
1001 * gpio_chrdev_open() - open the chardev for ioctl operations
1002 * @inode: inode for this chardev
1003 * @filp: file struct for storing private data
1004 * Returns 0 on success
1006 static int gpio_chrdev_open(struct inode
*inode
, struct file
*filp
)
1008 struct gpio_device
*gdev
= container_of(inode
->i_cdev
,
1009 struct gpio_device
, chrdev
);
1011 /* Fail on open if the backing gpiochip is gone */
1014 get_device(&gdev
->dev
);
1015 filp
->private_data
= gdev
;
1017 return nonseekable_open(inode
, filp
);
1021 * gpio_chrdev_release() - close chardev after ioctl operations
1022 * @inode: inode for this chardev
1023 * @filp: file struct for storing private data
1024 * Returns 0 on success
1026 static int gpio_chrdev_release(struct inode
*inode
, struct file
*filp
)
1028 struct gpio_device
*gdev
= container_of(inode
->i_cdev
,
1029 struct gpio_device
, chrdev
);
1031 put_device(&gdev
->dev
);
1036 static const struct file_operations gpio_fileops
= {
1037 .release
= gpio_chrdev_release
,
1038 .open
= gpio_chrdev_open
,
1039 .owner
= THIS_MODULE
,
1040 .llseek
= no_llseek
,
1041 .unlocked_ioctl
= gpio_ioctl
,
1042 #ifdef CONFIG_COMPAT
1043 .compat_ioctl
= gpio_ioctl_compat
,
1047 static void gpiodevice_release(struct device
*dev
)
1049 struct gpio_device
*gdev
= dev_get_drvdata(dev
);
1051 list_del(&gdev
->list
);
1052 ida_simple_remove(&gpio_ida
, gdev
->id
);
1058 static int gpiochip_setup_dev(struct gpio_device
*gdev
)
1062 cdev_init(&gdev
->chrdev
, &gpio_fileops
);
1063 gdev
->chrdev
.owner
= THIS_MODULE
;
1064 gdev
->dev
.devt
= MKDEV(MAJOR(gpio_devt
), gdev
->id
);
1066 status
= cdev_device_add(&gdev
->chrdev
, &gdev
->dev
);
1070 chip_dbg(gdev
->chip
, "added GPIO chardev (%d:%d)\n",
1071 MAJOR(gpio_devt
), gdev
->id
);
1073 status
= gpiochip_sysfs_register(gdev
);
1075 goto err_remove_device
;
1077 /* From this point, the .release() function cleans up gpio_device */
1078 gdev
->dev
.release
= gpiodevice_release
;
1079 pr_debug("%s: registered GPIOs %d to %d on device: %s (%s)\n",
1080 __func__
, gdev
->base
, gdev
->base
+ gdev
->ngpio
- 1,
1081 dev_name(&gdev
->dev
), gdev
->chip
->label
? : "generic");
1086 cdev_device_del(&gdev
->chrdev
, &gdev
->dev
);
1090 static void gpiochip_setup_devs(void)
1092 struct gpio_device
*gdev
;
1095 list_for_each_entry(gdev
, &gpio_devices
, list
) {
1096 err
= gpiochip_setup_dev(gdev
);
1098 pr_err("%s: Failed to initialize gpio device (%d)\n",
1099 dev_name(&gdev
->dev
), err
);
1103 int gpiochip_add_data_with_key(struct gpio_chip
*chip
, void *data
,
1104 struct lock_class_key
*lock_key
,
1105 struct lock_class_key
*request_key
)
1107 unsigned long flags
;
1110 int base
= chip
->base
;
1111 struct gpio_device
*gdev
;
1114 * First: allocate and populate the internal stat container, and
1115 * set up the struct device.
1117 gdev
= kzalloc(sizeof(*gdev
), GFP_KERNEL
);
1120 gdev
->dev
.bus
= &gpio_bus_type
;
1122 chip
->gpiodev
= gdev
;
1124 gdev
->dev
.parent
= chip
->parent
;
1125 gdev
->dev
.of_node
= chip
->parent
->of_node
;
1128 #ifdef CONFIG_OF_GPIO
1129 /* If the gpiochip has an assigned OF node this takes precedence */
1131 gdev
->dev
.of_node
= chip
->of_node
;
1134 gdev
->id
= ida_simple_get(&gpio_ida
, 0, 0, GFP_KERNEL
);
1139 dev_set_name(&gdev
->dev
, "gpiochip%d", gdev
->id
);
1140 device_initialize(&gdev
->dev
);
1141 dev_set_drvdata(&gdev
->dev
, gdev
);
1142 if (chip
->parent
&& chip
->parent
->driver
)
1143 gdev
->owner
= chip
->parent
->driver
->owner
;
1144 else if (chip
->owner
)
1145 /* TODO: remove chip->owner */
1146 gdev
->owner
= chip
->owner
;
1148 gdev
->owner
= THIS_MODULE
;
1150 gdev
->descs
= kcalloc(chip
->ngpio
, sizeof(gdev
->descs
[0]), GFP_KERNEL
);
1156 if (chip
->ngpio
== 0) {
1157 chip_err(chip
, "tried to insert a GPIO chip with zero lines\n");
1159 goto err_free_descs
;
1163 gdev
->label
= kstrdup(chip
->label
, GFP_KERNEL
);
1165 gdev
->label
= kstrdup("unknown", GFP_KERNEL
);
1168 goto err_free_descs
;
1171 gdev
->ngpio
= chip
->ngpio
;
1174 spin_lock_irqsave(&gpio_lock
, flags
);
1177 * TODO: this allocates a Linux GPIO number base in the global
1178 * GPIO numberspace for this chip. In the long run we want to
1179 * get *rid* of this numberspace and use only descriptors, but
1180 * it may be a pipe dream. It will not happen before we get rid
1181 * of the sysfs interface anyways.
1184 base
= gpiochip_find_base(chip
->ngpio
);
1187 spin_unlock_irqrestore(&gpio_lock
, flags
);
1188 goto err_free_label
;
1191 * TODO: it should not be necessary to reflect the assigned
1192 * base outside of the GPIO subsystem. Go over drivers and
1193 * see if anyone makes use of this, else drop this and assign
1200 status
= gpiodev_add_to_list(gdev
);
1202 spin_unlock_irqrestore(&gpio_lock
, flags
);
1203 goto err_free_label
;
1206 spin_unlock_irqrestore(&gpio_lock
, flags
);
1208 for (i
= 0; i
< chip
->ngpio
; i
++) {
1209 struct gpio_desc
*desc
= &gdev
->descs
[i
];
1213 * REVISIT: most hardware initializes GPIOs as inputs
1214 * (often with pullups enabled) so power usage is
1215 * minimized. Linux code should set the gpio direction
1216 * first thing; but until it does, and in case
1217 * chip->get_direction is not set, we may expose the
1218 * wrong direction in sysfs.
1221 if (chip
->get_direction
) {
1223 * If we have .get_direction, set up the initial
1224 * direction flag from the hardware.
1226 int dir
= chip
->get_direction(chip
, i
);
1229 set_bit(FLAG_IS_OUT
, &desc
->flags
);
1230 } else if (!chip
->direction_input
) {
1232 * If the chip lacks the .direction_input callback
1233 * we logically assume all lines are outputs.
1235 set_bit(FLAG_IS_OUT
, &desc
->flags
);
1239 #ifdef CONFIG_PINCTRL
1240 INIT_LIST_HEAD(&gdev
->pin_ranges
);
1243 status
= gpiochip_set_desc_names(chip
);
1245 goto err_remove_from_list
;
1247 status
= gpiochip_irqchip_init_valid_mask(chip
);
1249 goto err_remove_from_list
;
1251 status
= gpiochip_add_irqchip(chip
, lock_key
, request_key
);
1253 goto err_remove_chip
;
1255 status
= of_gpiochip_add(chip
);
1257 goto err_remove_chip
;
1259 acpi_gpiochip_add(chip
);
1262 * By first adding the chardev, and then adding the device,
1263 * we get a device node entry in sysfs under
1264 * /sys/bus/gpio/devices/gpiochipN/dev that can be used for
1265 * coldplug of device nodes and other udev business.
1266 * We can do this only if gpiolib has been initialized.
1267 * Otherwise, defer until later.
1269 if (gpiolib_initialized
) {
1270 status
= gpiochip_setup_dev(gdev
);
1272 goto err_remove_chip
;
1277 acpi_gpiochip_remove(chip
);
1278 gpiochip_free_hogs(chip
);
1279 of_gpiochip_remove(chip
);
1280 gpiochip_irqchip_free_valid_mask(chip
);
1281 err_remove_from_list
:
1282 spin_lock_irqsave(&gpio_lock
, flags
);
1283 list_del(&gdev
->list
);
1284 spin_unlock_irqrestore(&gpio_lock
, flags
);
1290 ida_simple_remove(&gpio_ida
, gdev
->id
);
1291 /* failures here can mean systems won't boot... */
1292 pr_err("%s: GPIOs %d..%d (%s) failed to register\n", __func__
,
1293 gdev
->base
, gdev
->base
+ gdev
->ngpio
- 1,
1294 chip
->label
? : "generic");
1298 EXPORT_SYMBOL_GPL(gpiochip_add_data_with_key
);
1301 * gpiochip_get_data() - get per-subdriver data for the chip
1305 * The per-subdriver data for the chip.
1307 void *gpiochip_get_data(struct gpio_chip
*chip
)
1309 return chip
->gpiodev
->data
;
1311 EXPORT_SYMBOL_GPL(gpiochip_get_data
);
1314 * gpiochip_remove() - unregister a gpio_chip
1315 * @chip: the chip to unregister
1317 * A gpio_chip with any GPIOs still requested may not be removed.
1319 void gpiochip_remove(struct gpio_chip
*chip
)
1321 struct gpio_device
*gdev
= chip
->gpiodev
;
1322 struct gpio_desc
*desc
;
1323 unsigned long flags
;
1325 bool requested
= false;
1327 /* FIXME: should the legacy sysfs handling be moved to gpio_device? */
1328 gpiochip_sysfs_unregister(gdev
);
1329 gpiochip_free_hogs(chip
);
1330 /* Numb the device, cancelling all outstanding operations */
1332 gpiochip_irqchip_remove(chip
);
1333 acpi_gpiochip_remove(chip
);
1334 gpiochip_remove_pin_ranges(chip
);
1335 of_gpiochip_remove(chip
);
1337 * We accept no more calls into the driver from this point, so
1338 * NULL the driver data pointer
1342 spin_lock_irqsave(&gpio_lock
, flags
);
1343 for (i
= 0; i
< gdev
->ngpio
; i
++) {
1344 desc
= &gdev
->descs
[i
];
1345 if (test_bit(FLAG_REQUESTED
, &desc
->flags
))
1348 spin_unlock_irqrestore(&gpio_lock
, flags
);
1351 dev_crit(&gdev
->dev
,
1352 "REMOVING GPIOCHIP WITH GPIOS STILL REQUESTED\n");
1355 * The gpiochip side puts its use of the device to rest here:
1356 * if there are no userspace clients, the chardev and device will
1357 * be removed, else it will be dangling until the last user is
1360 cdev_device_del(&gdev
->chrdev
, &gdev
->dev
);
1361 put_device(&gdev
->dev
);
1363 EXPORT_SYMBOL_GPL(gpiochip_remove
);
1365 static void devm_gpio_chip_release(struct device
*dev
, void *res
)
1367 struct gpio_chip
*chip
= *(struct gpio_chip
**)res
;
1369 gpiochip_remove(chip
);
1372 static int devm_gpio_chip_match(struct device
*dev
, void *res
, void *data
)
1375 struct gpio_chip
**r
= res
;
1386 * devm_gpiochip_add_data() - Resource manager piochip_add_data()
1387 * @dev: the device pointer on which irq_chip belongs to.
1388 * @chip: the chip to register, with chip->base initialized
1389 * @data: driver-private data associated with this chip
1391 * Context: potentially before irqs will work
1393 * The gpio chip automatically be released when the device is unbound.
1396 * A negative errno if the chip can't be registered, such as because the
1397 * chip->base is invalid or already associated with a different chip.
1398 * Otherwise it returns zero as a success code.
1400 int devm_gpiochip_add_data(struct device
*dev
, struct gpio_chip
*chip
,
1403 struct gpio_chip
**ptr
;
1406 ptr
= devres_alloc(devm_gpio_chip_release
, sizeof(*ptr
),
1411 ret
= gpiochip_add_data(chip
, data
);
1418 devres_add(dev
, ptr
);
1422 EXPORT_SYMBOL_GPL(devm_gpiochip_add_data
);
1425 * devm_gpiochip_remove() - Resource manager of gpiochip_remove()
1426 * @dev: device for which which resource was allocated
1427 * @chip: the chip to remove
1429 * A gpio_chip with any GPIOs still requested may not be removed.
1431 void devm_gpiochip_remove(struct device
*dev
, struct gpio_chip
*chip
)
1435 ret
= devres_release(dev
, devm_gpio_chip_release
,
1436 devm_gpio_chip_match
, chip
);
1439 EXPORT_SYMBOL_GPL(devm_gpiochip_remove
);
1442 * gpiochip_find() - iterator for locating a specific gpio_chip
1443 * @data: data to pass to match function
1444 * @match: Callback function to check gpio_chip
1446 * Similar to bus_find_device. It returns a reference to a gpio_chip as
1447 * determined by a user supplied @match callback. The callback should return
1448 * 0 if the device doesn't match and non-zero if it does. If the callback is
1449 * non-zero, this function will return to the caller and not iterate over any
1452 struct gpio_chip
*gpiochip_find(void *data
,
1453 int (*match
)(struct gpio_chip
*chip
,
1456 struct gpio_device
*gdev
;
1457 struct gpio_chip
*chip
= NULL
;
1458 unsigned long flags
;
1460 spin_lock_irqsave(&gpio_lock
, flags
);
1461 list_for_each_entry(gdev
, &gpio_devices
, list
)
1462 if (gdev
->chip
&& match(gdev
->chip
, data
)) {
1467 spin_unlock_irqrestore(&gpio_lock
, flags
);
1471 EXPORT_SYMBOL_GPL(gpiochip_find
);
1473 static int gpiochip_match_name(struct gpio_chip
*chip
, void *data
)
1475 const char *name
= data
;
1477 return !strcmp(chip
->label
, name
);
1480 static struct gpio_chip
*find_chip_by_name(const char *name
)
1482 return gpiochip_find((void *)name
, gpiochip_match_name
);
1485 #ifdef CONFIG_GPIOLIB_IRQCHIP
1488 * The following is irqchip helper code for gpiochips.
1491 static int gpiochip_irqchip_init_valid_mask(struct gpio_chip
*gpiochip
)
1493 if (!gpiochip
->irq
.need_valid_mask
)
1496 gpiochip
->irq
.valid_mask
= kcalloc(BITS_TO_LONGS(gpiochip
->ngpio
),
1497 sizeof(long), GFP_KERNEL
);
1498 if (!gpiochip
->irq
.valid_mask
)
1501 /* Assume by default all GPIOs are valid */
1502 bitmap_fill(gpiochip
->irq
.valid_mask
, gpiochip
->ngpio
);
1507 static void gpiochip_irqchip_free_valid_mask(struct gpio_chip
*gpiochip
)
1509 kfree(gpiochip
->irq
.valid_mask
);
1510 gpiochip
->irq
.valid_mask
= NULL
;
1513 static bool gpiochip_irqchip_irq_valid(const struct gpio_chip
*gpiochip
,
1514 unsigned int offset
)
1516 /* No mask means all valid */
1517 if (likely(!gpiochip
->irq
.valid_mask
))
1519 return test_bit(offset
, gpiochip
->irq
.valid_mask
);
1523 * gpiochip_set_cascaded_irqchip() - connects a cascaded irqchip to a gpiochip
1524 * @gpiochip: the gpiochip to set the irqchip chain to
1525 * @irqchip: the irqchip to chain to the gpiochip
1526 * @parent_irq: the irq number corresponding to the parent IRQ for this
1528 * @parent_handler: the parent interrupt handler for the accumulated IRQ
1529 * coming out of the gpiochip. If the interrupt is nested rather than
1530 * cascaded, pass NULL in this handler argument
1532 static void gpiochip_set_cascaded_irqchip(struct gpio_chip
*gpiochip
,
1533 struct irq_chip
*irqchip
,
1534 unsigned int parent_irq
,
1535 irq_flow_handler_t parent_handler
)
1537 unsigned int offset
;
1539 if (!gpiochip
->irq
.domain
) {
1540 chip_err(gpiochip
, "called %s before setting up irqchip\n",
1545 if (parent_handler
) {
1546 if (gpiochip
->can_sleep
) {
1548 "you cannot have chained interrupts on a "
1549 "chip that may sleep\n");
1553 * The parent irqchip is already using the chip_data for this
1554 * irqchip, so our callbacks simply use the handler_data.
1556 irq_set_chained_handler_and_data(parent_irq
, parent_handler
,
1559 gpiochip
->irq
.parents
= &parent_irq
;
1560 gpiochip
->irq
.num_parents
= 1;
1563 /* Set the parent IRQ for all affected IRQs */
1564 for (offset
= 0; offset
< gpiochip
->ngpio
; offset
++) {
1565 if (!gpiochip_irqchip_irq_valid(gpiochip
, offset
))
1567 irq_set_parent(irq_find_mapping(gpiochip
->irq
.domain
, offset
),
1573 * gpiochip_set_chained_irqchip() - connects a chained irqchip to a gpiochip
1574 * @gpiochip: the gpiochip to set the irqchip chain to
1575 * @irqchip: the irqchip to chain to the gpiochip
1576 * @parent_irq: the irq number corresponding to the parent IRQ for this
1578 * @parent_handler: the parent interrupt handler for the accumulated IRQ
1579 * coming out of the gpiochip. If the interrupt is nested rather than
1580 * cascaded, pass NULL in this handler argument
1582 void gpiochip_set_chained_irqchip(struct gpio_chip
*gpiochip
,
1583 struct irq_chip
*irqchip
,
1584 unsigned int parent_irq
,
1585 irq_flow_handler_t parent_handler
)
1587 if (gpiochip
->irq
.threaded
) {
1588 chip_err(gpiochip
, "tried to chain a threaded gpiochip\n");
1592 gpiochip_set_cascaded_irqchip(gpiochip
, irqchip
, parent_irq
,
1595 EXPORT_SYMBOL_GPL(gpiochip_set_chained_irqchip
);
1598 * gpiochip_set_nested_irqchip() - connects a nested irqchip to a gpiochip
1599 * @gpiochip: the gpiochip to set the irqchip nested handler to
1600 * @irqchip: the irqchip to nest to the gpiochip
1601 * @parent_irq: the irq number corresponding to the parent IRQ for this
1604 void gpiochip_set_nested_irqchip(struct gpio_chip
*gpiochip
,
1605 struct irq_chip
*irqchip
,
1606 unsigned int parent_irq
)
1608 gpiochip_set_cascaded_irqchip(gpiochip
, irqchip
, parent_irq
,
1611 EXPORT_SYMBOL_GPL(gpiochip_set_nested_irqchip
);
1614 * gpiochip_irq_map() - maps an IRQ into a GPIO irqchip
1615 * @d: the irqdomain used by this irqchip
1616 * @irq: the global irq number used by this GPIO irqchip irq
1617 * @hwirq: the local IRQ/GPIO line offset on this gpiochip
1619 * This function will set up the mapping for a certain IRQ line on a
1620 * gpiochip by assigning the gpiochip as chip data, and using the irqchip
1621 * stored inside the gpiochip.
1623 int gpiochip_irq_map(struct irq_domain
*d
, unsigned int irq
,
1624 irq_hw_number_t hwirq
)
1626 struct gpio_chip
*chip
= d
->host_data
;
1629 if (!gpiochip_irqchip_irq_valid(chip
, hwirq
))
1632 irq_set_chip_data(irq
, chip
);
1634 * This lock class tells lockdep that GPIO irqs are in a different
1635 * category than their parents, so it won't report false recursion.
1637 irq_set_lockdep_class(irq
, chip
->irq
.lock_key
, chip
->irq
.request_key
);
1638 irq_set_chip_and_handler(irq
, chip
->irq
.chip
, chip
->irq
.handler
);
1639 /* Chips that use nested thread handlers have them marked */
1640 if (chip
->irq
.threaded
)
1641 irq_set_nested_thread(irq
, 1);
1642 irq_set_noprobe(irq
);
1644 if (chip
->irq
.num_parents
== 1)
1645 err
= irq_set_parent(irq
, chip
->irq
.parents
[0]);
1646 else if (chip
->irq
.map
)
1647 err
= irq_set_parent(irq
, chip
->irq
.map
[hwirq
]);
1653 * No set-up of the hardware will happen if IRQ_TYPE_NONE
1654 * is passed as default type.
1656 if (chip
->irq
.default_type
!= IRQ_TYPE_NONE
)
1657 irq_set_irq_type(irq
, chip
->irq
.default_type
);
1661 EXPORT_SYMBOL_GPL(gpiochip_irq_map
);
1663 void gpiochip_irq_unmap(struct irq_domain
*d
, unsigned int irq
)
1665 struct gpio_chip
*chip
= d
->host_data
;
1667 if (chip
->irq
.threaded
)
1668 irq_set_nested_thread(irq
, 0);
1669 irq_set_chip_and_handler(irq
, NULL
, NULL
);
1670 irq_set_chip_data(irq
, NULL
);
1672 EXPORT_SYMBOL_GPL(gpiochip_irq_unmap
);
1674 static const struct irq_domain_ops gpiochip_domain_ops
= {
1675 .map
= gpiochip_irq_map
,
1676 .unmap
= gpiochip_irq_unmap
,
1677 /* Virtually all GPIO irqchips are twocell:ed */
1678 .xlate
= irq_domain_xlate_twocell
,
1681 static int gpiochip_irq_reqres(struct irq_data
*d
)
1683 struct gpio_chip
*chip
= irq_data_get_irq_chip_data(d
);
1685 if (!try_module_get(chip
->gpiodev
->owner
))
1688 if (gpiochip_lock_as_irq(chip
, d
->hwirq
)) {
1690 "unable to lock HW IRQ %lu for IRQ\n",
1692 module_put(chip
->gpiodev
->owner
);
1698 static void gpiochip_irq_relres(struct irq_data
*d
)
1700 struct gpio_chip
*chip
= irq_data_get_irq_chip_data(d
);
1702 gpiochip_unlock_as_irq(chip
, d
->hwirq
);
1703 module_put(chip
->gpiodev
->owner
);
1706 static int gpiochip_to_irq(struct gpio_chip
*chip
, unsigned offset
)
1708 if (!gpiochip_irqchip_irq_valid(chip
, offset
))
1711 return irq_create_mapping(chip
->irq
.domain
, offset
);
1715 * gpiochip_add_irqchip() - adds an IRQ chip to a GPIO chip
1716 * @gpiochip: the GPIO chip to add the IRQ chip to
1717 * @lock_key: lockdep class for IRQ lock
1718 * @request_key: lockdep class for IRQ request
1720 static int gpiochip_add_irqchip(struct gpio_chip
*gpiochip
,
1721 struct lock_class_key
*lock_key
,
1722 struct lock_class_key
*request_key
)
1724 struct irq_chip
*irqchip
= gpiochip
->irq
.chip
;
1725 const struct irq_domain_ops
*ops
;
1726 struct device_node
*np
;
1733 if (gpiochip
->irq
.parent_handler
&& gpiochip
->can_sleep
) {
1734 chip_err(gpiochip
, "you cannot have chained interrupts on a "
1735 "chip that may sleep\n");
1739 np
= gpiochip
->gpiodev
->dev
.of_node
;
1740 type
= gpiochip
->irq
.default_type
;
1743 * Specifying a default trigger is a terrible idea if DT or ACPI is
1744 * used to configure the interrupts, as you may end up with
1745 * conflicting triggers. Tell the user, and reset to NONE.
1747 if (WARN(np
&& type
!= IRQ_TYPE_NONE
,
1748 "%s: Ignoring %u default trigger\n", np
->full_name
, type
))
1749 type
= IRQ_TYPE_NONE
;
1751 if (has_acpi_companion(gpiochip
->parent
) && type
!= IRQ_TYPE_NONE
) {
1752 acpi_handle_warn(ACPI_HANDLE(gpiochip
->parent
),
1753 "Ignoring %u default trigger\n", type
);
1754 type
= IRQ_TYPE_NONE
;
1757 gpiochip
->to_irq
= gpiochip_to_irq
;
1758 gpiochip
->irq
.default_type
= type
;
1759 gpiochip
->irq
.lock_key
= lock_key
;
1760 gpiochip
->irq
.request_key
= request_key
;
1762 if (gpiochip
->irq
.domain_ops
)
1763 ops
= gpiochip
->irq
.domain_ops
;
1765 ops
= &gpiochip_domain_ops
;
1767 gpiochip
->irq
.domain
= irq_domain_add_simple(np
, gpiochip
->ngpio
,
1768 gpiochip
->irq
.first
,
1770 if (!gpiochip
->irq
.domain
)
1774 * It is possible for a driver to override this, but only if the
1775 * alternative functions are both implemented.
1777 if (!irqchip
->irq_request_resources
&&
1778 !irqchip
->irq_release_resources
) {
1779 irqchip
->irq_request_resources
= gpiochip_irq_reqres
;
1780 irqchip
->irq_release_resources
= gpiochip_irq_relres
;
1783 if (gpiochip
->irq
.parent_handler
) {
1784 void *data
= gpiochip
->irq
.parent_handler_data
?: gpiochip
;
1786 for (i
= 0; i
< gpiochip
->irq
.num_parents
; i
++) {
1788 * The parent IRQ chip is already using the chip_data
1789 * for this IRQ chip, so our callbacks simply use the
1792 irq_set_chained_handler_and_data(gpiochip
->irq
.parents
[i
],
1793 gpiochip
->irq
.parent_handler
,
1798 acpi_gpiochip_request_interrupts(gpiochip
);
1804 * gpiochip_irqchip_remove() - removes an irqchip added to a gpiochip
1805 * @gpiochip: the gpiochip to remove the irqchip from
1807 * This is called only from gpiochip_remove()
1809 static void gpiochip_irqchip_remove(struct gpio_chip
*gpiochip
)
1811 unsigned int offset
;
1813 acpi_gpiochip_free_interrupts(gpiochip
);
1815 if (gpiochip
->irq
.chip
&& gpiochip
->irq
.parent_handler
) {
1816 struct gpio_irq_chip
*irq
= &gpiochip
->irq
;
1819 for (i
= 0; i
< irq
->num_parents
; i
++)
1820 irq_set_chained_handler_and_data(irq
->parents
[i
],
1824 /* Remove all IRQ mappings and delete the domain */
1825 if (gpiochip
->irq
.domain
) {
1828 for (offset
= 0; offset
< gpiochip
->ngpio
; offset
++) {
1829 if (!gpiochip_irqchip_irq_valid(gpiochip
, offset
))
1832 irq
= irq_find_mapping(gpiochip
->irq
.domain
, offset
);
1833 irq_dispose_mapping(irq
);
1836 irq_domain_remove(gpiochip
->irq
.domain
);
1839 if (gpiochip
->irq
.chip
) {
1840 gpiochip
->irq
.chip
->irq_request_resources
= NULL
;
1841 gpiochip
->irq
.chip
->irq_release_resources
= NULL
;
1842 gpiochip
->irq
.chip
= NULL
;
1845 gpiochip_irqchip_free_valid_mask(gpiochip
);
1849 * gpiochip_irqchip_add_key() - adds an irqchip to a gpiochip
1850 * @gpiochip: the gpiochip to add the irqchip to
1851 * @irqchip: the irqchip to add to the gpiochip
1852 * @first_irq: if not dynamically assigned, the base (first) IRQ to
1853 * allocate gpiochip irqs from
1854 * @handler: the irq handler to use (often a predefined irq core function)
1855 * @type: the default type for IRQs on this irqchip, pass IRQ_TYPE_NONE
1856 * to have the core avoid setting up any default type in the hardware.
1857 * @threaded: whether this irqchip uses a nested thread handler
1858 * @lock_key: lockdep class for IRQ lock
1859 * @request_key: lockdep class for IRQ request
1861 * This function closely associates a certain irqchip with a certain
1862 * gpiochip, providing an irq domain to translate the local IRQs to
1863 * global irqs in the gpiolib core, and making sure that the gpiochip
1864 * is passed as chip data to all related functions. Driver callbacks
1865 * need to use gpiochip_get_data() to get their local state containers back
1866 * from the gpiochip passed as chip data. An irqdomain will be stored
1867 * in the gpiochip that shall be used by the driver to handle IRQ number
1868 * translation. The gpiochip will need to be initialized and registered
1869 * before calling this function.
1871 * This function will handle two cell:ed simple IRQs and assumes all
1872 * the pins on the gpiochip can generate a unique IRQ. Everything else
1873 * need to be open coded.
1875 int gpiochip_irqchip_add_key(struct gpio_chip
*gpiochip
,
1876 struct irq_chip
*irqchip
,
1877 unsigned int first_irq
,
1878 irq_flow_handler_t handler
,
1881 struct lock_class_key
*lock_key
,
1882 struct lock_class_key
*request_key
)
1884 struct device_node
*of_node
;
1886 if (!gpiochip
|| !irqchip
)
1889 if (!gpiochip
->parent
) {
1890 pr_err("missing gpiochip .dev parent pointer\n");
1893 gpiochip
->irq
.threaded
= threaded
;
1894 of_node
= gpiochip
->parent
->of_node
;
1895 #ifdef CONFIG_OF_GPIO
1897 * If the gpiochip has an assigned OF node this takes precedence
1898 * FIXME: get rid of this and use gpiochip->parent->of_node
1901 if (gpiochip
->of_node
)
1902 of_node
= gpiochip
->of_node
;
1905 * Specifying a default trigger is a terrible idea if DT or ACPI is
1906 * used to configure the interrupts, as you may end-up with
1907 * conflicting triggers. Tell the user, and reset to NONE.
1909 if (WARN(of_node
&& type
!= IRQ_TYPE_NONE
,
1910 "%pOF: Ignoring %d default trigger\n", of_node
, type
))
1911 type
= IRQ_TYPE_NONE
;
1912 if (has_acpi_companion(gpiochip
->parent
) && type
!= IRQ_TYPE_NONE
) {
1913 acpi_handle_warn(ACPI_HANDLE(gpiochip
->parent
),
1914 "Ignoring %d default trigger\n", type
);
1915 type
= IRQ_TYPE_NONE
;
1918 gpiochip
->irq
.chip
= irqchip
;
1919 gpiochip
->irq
.handler
= handler
;
1920 gpiochip
->irq
.default_type
= type
;
1921 gpiochip
->to_irq
= gpiochip_to_irq
;
1922 gpiochip
->irq
.lock_key
= lock_key
;
1923 gpiochip
->irq
.request_key
= request_key
;
1924 gpiochip
->irq
.domain
= irq_domain_add_simple(of_node
,
1925 gpiochip
->ngpio
, first_irq
,
1926 &gpiochip_domain_ops
, gpiochip
);
1927 if (!gpiochip
->irq
.domain
) {
1928 gpiochip
->irq
.chip
= NULL
;
1933 * It is possible for a driver to override this, but only if the
1934 * alternative functions are both implemented.
1936 if (!irqchip
->irq_request_resources
&&
1937 !irqchip
->irq_release_resources
) {
1938 irqchip
->irq_request_resources
= gpiochip_irq_reqres
;
1939 irqchip
->irq_release_resources
= gpiochip_irq_relres
;
1942 acpi_gpiochip_request_interrupts(gpiochip
);
1946 EXPORT_SYMBOL_GPL(gpiochip_irqchip_add_key
);
1948 #else /* CONFIG_GPIOLIB_IRQCHIP */
1950 static inline int gpiochip_add_irqchip(struct gpio_chip
*gpiochip
,
1951 struct lock_class_key
*lock_key
,
1952 struct lock_class_key
*request_key
)
1957 static void gpiochip_irqchip_remove(struct gpio_chip
*gpiochip
) {}
1958 static inline int gpiochip_irqchip_init_valid_mask(struct gpio_chip
*gpiochip
)
1962 static inline void gpiochip_irqchip_free_valid_mask(struct gpio_chip
*gpiochip
)
1965 #endif /* CONFIG_GPIOLIB_IRQCHIP */
1968 * gpiochip_generic_request() - request the gpio function for a pin
1969 * @chip: the gpiochip owning the GPIO
1970 * @offset: the offset of the GPIO to request for GPIO function
1972 int gpiochip_generic_request(struct gpio_chip
*chip
, unsigned offset
)
1974 return pinctrl_gpio_request(chip
->gpiodev
->base
+ offset
);
1976 EXPORT_SYMBOL_GPL(gpiochip_generic_request
);
1979 * gpiochip_generic_free() - free the gpio function from a pin
1980 * @chip: the gpiochip to request the gpio function for
1981 * @offset: the offset of the GPIO to free from GPIO function
1983 void gpiochip_generic_free(struct gpio_chip
*chip
, unsigned offset
)
1985 pinctrl_gpio_free(chip
->gpiodev
->base
+ offset
);
1987 EXPORT_SYMBOL_GPL(gpiochip_generic_free
);
1990 * gpiochip_generic_config() - apply configuration for a pin
1991 * @chip: the gpiochip owning the GPIO
1992 * @offset: the offset of the GPIO to apply the configuration
1993 * @config: the configuration to be applied
1995 int gpiochip_generic_config(struct gpio_chip
*chip
, unsigned offset
,
1996 unsigned long config
)
1998 return pinctrl_gpio_set_config(chip
->gpiodev
->base
+ offset
, config
);
2000 EXPORT_SYMBOL_GPL(gpiochip_generic_config
);
2002 #ifdef CONFIG_PINCTRL
2005 * gpiochip_add_pingroup_range() - add a range for GPIO <-> pin mapping
2006 * @chip: the gpiochip to add the range for
2007 * @pctldev: the pin controller to map to
2008 * @gpio_offset: the start offset in the current gpio_chip number space
2009 * @pin_group: name of the pin group inside the pin controller
2011 int gpiochip_add_pingroup_range(struct gpio_chip
*chip
,
2012 struct pinctrl_dev
*pctldev
,
2013 unsigned int gpio_offset
, const char *pin_group
)
2015 struct gpio_pin_range
*pin_range
;
2016 struct gpio_device
*gdev
= chip
->gpiodev
;
2019 pin_range
= kzalloc(sizeof(*pin_range
), GFP_KERNEL
);
2021 chip_err(chip
, "failed to allocate pin ranges\n");
2025 /* Use local offset as range ID */
2026 pin_range
->range
.id
= gpio_offset
;
2027 pin_range
->range
.gc
= chip
;
2028 pin_range
->range
.name
= chip
->label
;
2029 pin_range
->range
.base
= gdev
->base
+ gpio_offset
;
2030 pin_range
->pctldev
= pctldev
;
2032 ret
= pinctrl_get_group_pins(pctldev
, pin_group
,
2033 &pin_range
->range
.pins
,
2034 &pin_range
->range
.npins
);
2040 pinctrl_add_gpio_range(pctldev
, &pin_range
->range
);
2042 chip_dbg(chip
, "created GPIO range %d->%d ==> %s PINGRP %s\n",
2043 gpio_offset
, gpio_offset
+ pin_range
->range
.npins
- 1,
2044 pinctrl_dev_get_devname(pctldev
), pin_group
);
2046 list_add_tail(&pin_range
->node
, &gdev
->pin_ranges
);
2050 EXPORT_SYMBOL_GPL(gpiochip_add_pingroup_range
);
2053 * gpiochip_add_pin_range() - add a range for GPIO <-> pin mapping
2054 * @chip: the gpiochip to add the range for
2055 * @pinctl_name: the dev_name() of the pin controller to map to
2056 * @gpio_offset: the start offset in the current gpio_chip number space
2057 * @pin_offset: the start offset in the pin controller number space
2058 * @npins: the number of pins from the offset of each pin space (GPIO and
2059 * pin controller) to accumulate in this range
2062 * 0 on success, or a negative error-code on failure.
2064 int gpiochip_add_pin_range(struct gpio_chip
*chip
, const char *pinctl_name
,
2065 unsigned int gpio_offset
, unsigned int pin_offset
,
2068 struct gpio_pin_range
*pin_range
;
2069 struct gpio_device
*gdev
= chip
->gpiodev
;
2072 pin_range
= kzalloc(sizeof(*pin_range
), GFP_KERNEL
);
2074 chip_err(chip
, "failed to allocate pin ranges\n");
2078 /* Use local offset as range ID */
2079 pin_range
->range
.id
= gpio_offset
;
2080 pin_range
->range
.gc
= chip
;
2081 pin_range
->range
.name
= chip
->label
;
2082 pin_range
->range
.base
= gdev
->base
+ gpio_offset
;
2083 pin_range
->range
.pin_base
= pin_offset
;
2084 pin_range
->range
.npins
= npins
;
2085 pin_range
->pctldev
= pinctrl_find_and_add_gpio_range(pinctl_name
,
2087 if (IS_ERR(pin_range
->pctldev
)) {
2088 ret
= PTR_ERR(pin_range
->pctldev
);
2089 chip_err(chip
, "could not create pin range\n");
2093 chip_dbg(chip
, "created GPIO range %d->%d ==> %s PIN %d->%d\n",
2094 gpio_offset
, gpio_offset
+ npins
- 1,
2096 pin_offset
, pin_offset
+ npins
- 1);
2098 list_add_tail(&pin_range
->node
, &gdev
->pin_ranges
);
2102 EXPORT_SYMBOL_GPL(gpiochip_add_pin_range
);
2105 * gpiochip_remove_pin_ranges() - remove all the GPIO <-> pin mappings
2106 * @chip: the chip to remove all the mappings for
2108 void gpiochip_remove_pin_ranges(struct gpio_chip
*chip
)
2110 struct gpio_pin_range
*pin_range
, *tmp
;
2111 struct gpio_device
*gdev
= chip
->gpiodev
;
2113 list_for_each_entry_safe(pin_range
, tmp
, &gdev
->pin_ranges
, node
) {
2114 list_del(&pin_range
->node
);
2115 pinctrl_remove_gpio_range(pin_range
->pctldev
,
2120 EXPORT_SYMBOL_GPL(gpiochip_remove_pin_ranges
);
2122 #endif /* CONFIG_PINCTRL */
2124 /* These "optional" allocation calls help prevent drivers from stomping
2125 * on each other, and help provide better diagnostics in debugfs.
2126 * They're called even less than the "set direction" calls.
2128 static int gpiod_request_commit(struct gpio_desc
*desc
, const char *label
)
2130 struct gpio_chip
*chip
= desc
->gdev
->chip
;
2132 unsigned long flags
;
2134 spin_lock_irqsave(&gpio_lock
, flags
);
2136 /* NOTE: gpio_request() can be called in early boot,
2137 * before IRQs are enabled, for non-sleeping (SOC) GPIOs.
2140 if (test_and_set_bit(FLAG_REQUESTED
, &desc
->flags
) == 0) {
2141 desc_set_label(desc
, label
? : "?");
2148 if (chip
->request
) {
2149 /* chip->request may sleep */
2150 spin_unlock_irqrestore(&gpio_lock
, flags
);
2151 status
= chip
->request(chip
, gpio_chip_hwgpio(desc
));
2152 spin_lock_irqsave(&gpio_lock
, flags
);
2155 desc_set_label(desc
, NULL
);
2156 clear_bit(FLAG_REQUESTED
, &desc
->flags
);
2160 if (chip
->get_direction
) {
2161 /* chip->get_direction may sleep */
2162 spin_unlock_irqrestore(&gpio_lock
, flags
);
2163 gpiod_get_direction(desc
);
2164 spin_lock_irqsave(&gpio_lock
, flags
);
2167 spin_unlock_irqrestore(&gpio_lock
, flags
);
2172 * This descriptor validation needs to be inserted verbatim into each
2173 * function taking a descriptor, so we need to use a preprocessor
2174 * macro to avoid endless duplication. If the desc is NULL it is an
2175 * optional GPIO and calls should just bail out.
2177 #define VALIDATE_DESC(desc) do { \
2180 if (IS_ERR(desc)) { \
2181 pr_warn("%s: invalid GPIO (errorpointer)\n", __func__); \
2182 return PTR_ERR(desc); \
2184 if (!desc->gdev) { \
2185 pr_warn("%s: invalid GPIO (no device)\n", __func__); \
2188 if ( !desc->gdev->chip ) { \
2189 dev_warn(&desc->gdev->dev, \
2190 "%s: backing chip is gone\n", __func__); \
2194 #define VALIDATE_DESC_VOID(desc) do { \
2197 if (IS_ERR(desc)) { \
2198 pr_warn("%s: invalid GPIO (errorpointer)\n", __func__); \
2201 if (!desc->gdev) { \
2202 pr_warn("%s: invalid GPIO (no device)\n", __func__); \
2205 if (!desc->gdev->chip) { \
2206 dev_warn(&desc->gdev->dev, \
2207 "%s: backing chip is gone\n", __func__); \
2212 int gpiod_request(struct gpio_desc
*desc
, const char *label
)
2214 int status
= -EPROBE_DEFER
;
2215 struct gpio_device
*gdev
;
2217 VALIDATE_DESC(desc
);
2220 if (try_module_get(gdev
->owner
)) {
2221 status
= gpiod_request_commit(desc
, label
);
2223 module_put(gdev
->owner
);
2225 get_device(&gdev
->dev
);
2229 gpiod_dbg(desc
, "%s: status %d\n", __func__
, status
);
2234 static bool gpiod_free_commit(struct gpio_desc
*desc
)
2237 unsigned long flags
;
2238 struct gpio_chip
*chip
;
2242 gpiod_unexport(desc
);
2244 spin_lock_irqsave(&gpio_lock
, flags
);
2246 chip
= desc
->gdev
->chip
;
2247 if (chip
&& test_bit(FLAG_REQUESTED
, &desc
->flags
)) {
2249 spin_unlock_irqrestore(&gpio_lock
, flags
);
2250 might_sleep_if(chip
->can_sleep
);
2251 chip
->free(chip
, gpio_chip_hwgpio(desc
));
2252 spin_lock_irqsave(&gpio_lock
, flags
);
2254 desc_set_label(desc
, NULL
);
2255 clear_bit(FLAG_ACTIVE_LOW
, &desc
->flags
);
2256 clear_bit(FLAG_REQUESTED
, &desc
->flags
);
2257 clear_bit(FLAG_OPEN_DRAIN
, &desc
->flags
);
2258 clear_bit(FLAG_OPEN_SOURCE
, &desc
->flags
);
2259 clear_bit(FLAG_IS_HOGGED
, &desc
->flags
);
2263 spin_unlock_irqrestore(&gpio_lock
, flags
);
2267 void gpiod_free(struct gpio_desc
*desc
)
2269 if (desc
&& desc
->gdev
&& gpiod_free_commit(desc
)) {
2270 module_put(desc
->gdev
->owner
);
2271 put_device(&desc
->gdev
->dev
);
2273 WARN_ON(extra_checks
);
2278 * gpiochip_is_requested - return string iff signal was requested
2279 * @chip: controller managing the signal
2280 * @offset: of signal within controller's 0..(ngpio - 1) range
2282 * Returns NULL if the GPIO is not currently requested, else a string.
2283 * The string returned is the label passed to gpio_request(); if none has been
2284 * passed it is a meaningless, non-NULL constant.
2286 * This function is for use by GPIO controller drivers. The label can
2287 * help with diagnostics, and knowing that the signal is used as a GPIO
2288 * can help avoid accidentally multiplexing it to another controller.
2290 const char *gpiochip_is_requested(struct gpio_chip
*chip
, unsigned offset
)
2292 struct gpio_desc
*desc
;
2294 if (offset
>= chip
->ngpio
)
2297 desc
= &chip
->gpiodev
->descs
[offset
];
2299 if (test_bit(FLAG_REQUESTED
, &desc
->flags
) == 0)
2303 EXPORT_SYMBOL_GPL(gpiochip_is_requested
);
2306 * gpiochip_request_own_desc - Allow GPIO chip to request its own descriptor
2308 * @hwnum: hardware number of the GPIO for which to request the descriptor
2309 * @label: label for the GPIO
2311 * Function allows GPIO chip drivers to request and use their own GPIO
2312 * descriptors via gpiolib API. Difference to gpiod_request() is that this
2313 * function will not increase reference count of the GPIO chip module. This
2314 * allows the GPIO chip module to be unloaded as needed (we assume that the
2315 * GPIO chip driver handles freeing the GPIOs it has requested).
2318 * A pointer to the GPIO descriptor, or an ERR_PTR()-encoded negative error
2321 struct gpio_desc
*gpiochip_request_own_desc(struct gpio_chip
*chip
, u16 hwnum
,
2324 struct gpio_desc
*desc
= gpiochip_get_desc(chip
, hwnum
);
2328 chip_err(chip
, "failed to get GPIO descriptor\n");
2332 err
= gpiod_request_commit(desc
, label
);
2334 return ERR_PTR(err
);
2338 EXPORT_SYMBOL_GPL(gpiochip_request_own_desc
);
2341 * gpiochip_free_own_desc - Free GPIO requested by the chip driver
2342 * @desc: GPIO descriptor to free
2344 * Function frees the given GPIO requested previously with
2345 * gpiochip_request_own_desc().
2347 void gpiochip_free_own_desc(struct gpio_desc
*desc
)
2350 gpiod_free_commit(desc
);
2352 EXPORT_SYMBOL_GPL(gpiochip_free_own_desc
);
2355 * Drivers MUST set GPIO direction before making get/set calls. In
2356 * some cases this is done in early boot, before IRQs are enabled.
2358 * As a rule these aren't called more than once (except for drivers
2359 * using the open-drain emulation idiom) so these are natural places
2360 * to accumulate extra debugging checks. Note that we can't (yet)
2361 * rely on gpio_request() having been called beforehand.
2365 * gpiod_direction_input - set the GPIO direction to input
2366 * @desc: GPIO to set to input
2368 * Set the direction of the passed GPIO to input, such as gpiod_get_value() can
2369 * be called safely on it.
2371 * Return 0 in case of success, else an error code.
2373 int gpiod_direction_input(struct gpio_desc
*desc
)
2375 struct gpio_chip
*chip
;
2376 int status
= -EINVAL
;
2378 VALIDATE_DESC(desc
);
2379 chip
= desc
->gdev
->chip
;
2381 if (!chip
->get
|| !chip
->direction_input
) {
2383 "%s: missing get() or direction_input() operations\n",
2388 status
= chip
->direction_input(chip
, gpio_chip_hwgpio(desc
));
2390 clear_bit(FLAG_IS_OUT
, &desc
->flags
);
2392 trace_gpio_direction(desc_to_gpio(desc
), 1, status
);
2396 EXPORT_SYMBOL_GPL(gpiod_direction_input
);
2398 static int gpio_set_drive_single_ended(struct gpio_chip
*gc
, unsigned offset
,
2399 enum pin_config_param mode
)
2401 unsigned long config
= { PIN_CONF_PACKED(mode
, 0) };
2403 return gc
->set_config
? gc
->set_config(gc
, offset
, config
) : -ENOTSUPP
;
2406 static int gpiod_direction_output_raw_commit(struct gpio_desc
*desc
, int value
)
2408 struct gpio_chip
*gc
= desc
->gdev
->chip
;
2412 if (!gc
->set
|| !gc
->direction_output
) {
2414 "%s: missing set() or direction_output() operations\n",
2419 ret
= gc
->direction_output(gc
, gpio_chip_hwgpio(desc
), val
);
2421 set_bit(FLAG_IS_OUT
, &desc
->flags
);
2422 trace_gpio_value(desc_to_gpio(desc
), 0, val
);
2423 trace_gpio_direction(desc_to_gpio(desc
), 0, ret
);
2428 * gpiod_direction_output_raw - set the GPIO direction to output
2429 * @desc: GPIO to set to output
2430 * @value: initial output value of the GPIO
2432 * Set the direction of the passed GPIO to output, such as gpiod_set_value() can
2433 * be called safely on it. The initial value of the output must be specified
2434 * as raw value on the physical line without regard for the ACTIVE_LOW status.
2436 * Return 0 in case of success, else an error code.
2438 int gpiod_direction_output_raw(struct gpio_desc
*desc
, int value
)
2440 VALIDATE_DESC(desc
);
2441 return gpiod_direction_output_raw_commit(desc
, value
);
2443 EXPORT_SYMBOL_GPL(gpiod_direction_output_raw
);
2446 * gpiod_direction_output - set the GPIO direction to output
2447 * @desc: GPIO to set to output
2448 * @value: initial output value of the GPIO
2450 * Set the direction of the passed GPIO to output, such as gpiod_set_value() can
2451 * be called safely on it. The initial value of the output must be specified
2452 * as the logical value of the GPIO, i.e. taking its ACTIVE_LOW status into
2455 * Return 0 in case of success, else an error code.
2457 int gpiod_direction_output(struct gpio_desc
*desc
, int value
)
2459 struct gpio_chip
*gc
= desc
->gdev
->chip
;
2462 VALIDATE_DESC(desc
);
2463 if (test_bit(FLAG_ACTIVE_LOW
, &desc
->flags
))
2468 /* GPIOs used for IRQs shall not be set as output */
2469 if (test_bit(FLAG_USED_AS_IRQ
, &desc
->flags
)) {
2471 "%s: tried to set a GPIO tied to an IRQ as output\n",
2476 if (test_bit(FLAG_OPEN_DRAIN
, &desc
->flags
)) {
2477 /* First see if we can enable open drain in hardware */
2478 ret
= gpio_set_drive_single_ended(gc
, gpio_chip_hwgpio(desc
),
2479 PIN_CONFIG_DRIVE_OPEN_DRAIN
);
2481 goto set_output_value
;
2482 /* Emulate open drain by not actively driving the line high */
2484 return gpiod_direction_input(desc
);
2486 else if (test_bit(FLAG_OPEN_SOURCE
, &desc
->flags
)) {
2487 ret
= gpio_set_drive_single_ended(gc
, gpio_chip_hwgpio(desc
),
2488 PIN_CONFIG_DRIVE_OPEN_SOURCE
);
2490 goto set_output_value
;
2491 /* Emulate open source by not actively driving the line low */
2493 return gpiod_direction_input(desc
);
2495 gpio_set_drive_single_ended(gc
, gpio_chip_hwgpio(desc
),
2496 PIN_CONFIG_DRIVE_PUSH_PULL
);
2500 return gpiod_direction_output_raw_commit(desc
, value
);
2502 EXPORT_SYMBOL_GPL(gpiod_direction_output
);
2505 * gpiod_set_debounce - sets @debounce time for a GPIO
2506 * @desc: descriptor of the GPIO for which to set debounce time
2507 * @debounce: debounce time in microseconds
2510 * 0 on success, %-ENOTSUPP if the controller doesn't support setting the
2513 int gpiod_set_debounce(struct gpio_desc
*desc
, unsigned debounce
)
2515 struct gpio_chip
*chip
;
2516 unsigned long config
;
2518 VALIDATE_DESC(desc
);
2519 chip
= desc
->gdev
->chip
;
2520 if (!chip
->set
|| !chip
->set_config
) {
2522 "%s: missing set() or set_config() operations\n",
2527 config
= pinconf_to_config_packed(PIN_CONFIG_INPUT_DEBOUNCE
, debounce
);
2528 return chip
->set_config(chip
, gpio_chip_hwgpio(desc
), config
);
2530 EXPORT_SYMBOL_GPL(gpiod_set_debounce
);
2533 * gpiod_is_active_low - test whether a GPIO is active-low or not
2534 * @desc: the gpio descriptor to test
2536 * Returns 1 if the GPIO is active-low, 0 otherwise.
2538 int gpiod_is_active_low(const struct gpio_desc
*desc
)
2540 VALIDATE_DESC(desc
);
2541 return test_bit(FLAG_ACTIVE_LOW
, &desc
->flags
);
2543 EXPORT_SYMBOL_GPL(gpiod_is_active_low
);
2545 /* I/O calls are only valid after configuration completed; the relevant
2546 * "is this a valid GPIO" error checks should already have been done.
2548 * "Get" operations are often inlinable as reading a pin value register,
2549 * and masking the relevant bit in that register.
2551 * When "set" operations are inlinable, they involve writing that mask to
2552 * one register to set a low value, or a different register to set it high.
2553 * Otherwise locking is needed, so there may be little value to inlining.
2555 *------------------------------------------------------------------------
2557 * IMPORTANT!!! The hot paths -- get/set value -- assume that callers
2558 * have requested the GPIO. That can include implicit requesting by
2559 * a direction setting call. Marking a gpio as requested locks its chip
2560 * in memory, guaranteeing that these table lookups need no more locking
2561 * and that gpiochip_remove() will fail.
2563 * REVISIT when debugging, consider adding some instrumentation to ensure
2564 * that the GPIO was actually requested.
2567 static int gpiod_get_raw_value_commit(const struct gpio_desc
*desc
)
2569 struct gpio_chip
*chip
;
2573 chip
= desc
->gdev
->chip
;
2574 offset
= gpio_chip_hwgpio(desc
);
2575 value
= chip
->get
? chip
->get(chip
, offset
) : -EIO
;
2576 value
= value
< 0 ? value
: !!value
;
2577 trace_gpio_value(desc_to_gpio(desc
), 1, value
);
2581 static int gpio_chip_get_multiple(struct gpio_chip
*chip
,
2582 unsigned long *mask
, unsigned long *bits
)
2584 if (chip
->get_multiple
) {
2585 return chip
->get_multiple(chip
, mask
, bits
);
2586 } else if (chip
->get
) {
2589 for_each_set_bit(i
, mask
, chip
->ngpio
) {
2590 value
= chip
->get(chip
, i
);
2593 __assign_bit(i
, bits
, value
);
2600 int gpiod_get_array_value_complex(bool raw
, bool can_sleep
,
2601 unsigned int array_size
,
2602 struct gpio_desc
**desc_array
,
2607 while (i
< array_size
) {
2608 struct gpio_chip
*chip
= desc_array
[i
]->gdev
->chip
;
2609 unsigned long mask
[BITS_TO_LONGS(chip
->ngpio
)];
2610 unsigned long bits
[BITS_TO_LONGS(chip
->ngpio
)];
2614 WARN_ON(chip
->can_sleep
);
2616 /* collect all inputs belonging to the same chip */
2618 memset(mask
, 0, sizeof(mask
));
2620 const struct gpio_desc
*desc
= desc_array
[i
];
2621 int hwgpio
= gpio_chip_hwgpio(desc
);
2623 __set_bit(hwgpio
, mask
);
2625 } while ((i
< array_size
) &&
2626 (desc_array
[i
]->gdev
->chip
== chip
));
2628 ret
= gpio_chip_get_multiple(chip
, mask
, bits
);
2632 for (j
= first
; j
< i
; j
++) {
2633 const struct gpio_desc
*desc
= desc_array
[j
];
2634 int hwgpio
= gpio_chip_hwgpio(desc
);
2635 int value
= test_bit(hwgpio
, bits
);
2637 if (!raw
&& test_bit(FLAG_ACTIVE_LOW
, &desc
->flags
))
2639 value_array
[j
] = value
;
2640 trace_gpio_value(desc_to_gpio(desc
), 1, value
);
2647 * gpiod_get_raw_value() - return a gpio's raw value
2648 * @desc: gpio whose value will be returned
2650 * Return the GPIO's raw value, i.e. the value of the physical line disregarding
2651 * its ACTIVE_LOW status, or negative errno on failure.
2653 * This function should be called from contexts where we cannot sleep, and will
2654 * complain if the GPIO chip functions potentially sleep.
2656 int gpiod_get_raw_value(const struct gpio_desc
*desc
)
2658 VALIDATE_DESC(desc
);
2659 /* Should be using gpio_get_value_cansleep() */
2660 WARN_ON(desc
->gdev
->chip
->can_sleep
);
2661 return gpiod_get_raw_value_commit(desc
);
2663 EXPORT_SYMBOL_GPL(gpiod_get_raw_value
);
2666 * gpiod_get_value() - return a gpio's value
2667 * @desc: gpio whose value will be returned
2669 * Return the GPIO's logical value, i.e. taking the ACTIVE_LOW status into
2670 * account, or negative errno on failure.
2672 * This function should be called from contexts where we cannot sleep, and will
2673 * complain if the GPIO chip functions potentially sleep.
2675 int gpiod_get_value(const struct gpio_desc
*desc
)
2679 VALIDATE_DESC(desc
);
2680 /* Should be using gpio_get_value_cansleep() */
2681 WARN_ON(desc
->gdev
->chip
->can_sleep
);
2683 value
= gpiod_get_raw_value_commit(desc
);
2687 if (test_bit(FLAG_ACTIVE_LOW
, &desc
->flags
))
2692 EXPORT_SYMBOL_GPL(gpiod_get_value
);
2695 * gpiod_get_raw_array_value() - read raw values from an array of GPIOs
2696 * @array_size: number of elements in the descriptor / value arrays
2697 * @desc_array: array of GPIO descriptors whose values will be read
2698 * @value_array: array to store the read values
2700 * Read the raw values of the GPIOs, i.e. the values of the physical lines
2701 * without regard for their ACTIVE_LOW status. Return 0 in case of success,
2702 * else an error code.
2704 * This function should be called from contexts where we cannot sleep,
2705 * and it will complain if the GPIO chip functions potentially sleep.
2707 int gpiod_get_raw_array_value(unsigned int array_size
,
2708 struct gpio_desc
**desc_array
, int *value_array
)
2712 return gpiod_get_array_value_complex(true, false, array_size
,
2713 desc_array
, value_array
);
2715 EXPORT_SYMBOL_GPL(gpiod_get_raw_array_value
);
2718 * gpiod_get_array_value() - read values from an array of GPIOs
2719 * @array_size: number of elements in the descriptor / value arrays
2720 * @desc_array: array of GPIO descriptors whose values will be read
2721 * @value_array: array to store the read values
2723 * Read the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status
2724 * into account. Return 0 in case of success, else an error code.
2726 * This function should be called from contexts where we cannot sleep,
2727 * and it will complain if the GPIO chip functions potentially sleep.
2729 int gpiod_get_array_value(unsigned int array_size
,
2730 struct gpio_desc
**desc_array
, int *value_array
)
2734 return gpiod_get_array_value_complex(false, false, array_size
,
2735 desc_array
, value_array
);
2737 EXPORT_SYMBOL_GPL(gpiod_get_array_value
);
2740 * gpio_set_open_drain_value_commit() - Set the open drain gpio's value.
2741 * @desc: gpio descriptor whose state need to be set.
2742 * @value: Non-zero for setting it HIGH otherwise it will set to LOW.
2744 static void gpio_set_open_drain_value_commit(struct gpio_desc
*desc
, bool value
)
2747 struct gpio_chip
*chip
= desc
->gdev
->chip
;
2748 int offset
= gpio_chip_hwgpio(desc
);
2751 err
= chip
->direction_input(chip
, offset
);
2753 clear_bit(FLAG_IS_OUT
, &desc
->flags
);
2755 err
= chip
->direction_output(chip
, offset
, 0);
2757 set_bit(FLAG_IS_OUT
, &desc
->flags
);
2759 trace_gpio_direction(desc_to_gpio(desc
), value
, err
);
2762 "%s: Error in set_value for open drain err %d\n",
2767 * _gpio_set_open_source_value() - Set the open source gpio's value.
2768 * @desc: gpio descriptor whose state need to be set.
2769 * @value: Non-zero for setting it HIGH otherwise it will set to LOW.
2771 static void gpio_set_open_source_value_commit(struct gpio_desc
*desc
, bool value
)
2774 struct gpio_chip
*chip
= desc
->gdev
->chip
;
2775 int offset
= gpio_chip_hwgpio(desc
);
2778 err
= chip
->direction_output(chip
, offset
, 1);
2780 set_bit(FLAG_IS_OUT
, &desc
->flags
);
2782 err
= chip
->direction_input(chip
, offset
);
2784 clear_bit(FLAG_IS_OUT
, &desc
->flags
);
2786 trace_gpio_direction(desc_to_gpio(desc
), !value
, err
);
2789 "%s: Error in set_value for open source err %d\n",
2793 static void gpiod_set_raw_value_commit(struct gpio_desc
*desc
, bool value
)
2795 struct gpio_chip
*chip
;
2797 chip
= desc
->gdev
->chip
;
2798 trace_gpio_value(desc_to_gpio(desc
), 0, value
);
2799 chip
->set(chip
, gpio_chip_hwgpio(desc
), value
);
2803 * set multiple outputs on the same chip;
2804 * use the chip's set_multiple function if available;
2805 * otherwise set the outputs sequentially;
2806 * @mask: bit mask array; one bit per output; BITS_PER_LONG bits per word
2807 * defines which outputs are to be changed
2808 * @bits: bit value array; one bit per output; BITS_PER_LONG bits per word
2809 * defines the values the outputs specified by mask are to be set to
2811 static void gpio_chip_set_multiple(struct gpio_chip
*chip
,
2812 unsigned long *mask
, unsigned long *bits
)
2814 if (chip
->set_multiple
) {
2815 chip
->set_multiple(chip
, mask
, bits
);
2819 /* set outputs if the corresponding mask bit is set */
2820 for_each_set_bit(i
, mask
, chip
->ngpio
)
2821 chip
->set(chip
, i
, test_bit(i
, bits
));
2825 void gpiod_set_array_value_complex(bool raw
, bool can_sleep
,
2826 unsigned int array_size
,
2827 struct gpio_desc
**desc_array
,
2832 while (i
< array_size
) {
2833 struct gpio_chip
*chip
= desc_array
[i
]->gdev
->chip
;
2834 unsigned long mask
[BITS_TO_LONGS(chip
->ngpio
)];
2835 unsigned long bits
[BITS_TO_LONGS(chip
->ngpio
)];
2839 WARN_ON(chip
->can_sleep
);
2841 memset(mask
, 0, sizeof(mask
));
2843 struct gpio_desc
*desc
= desc_array
[i
];
2844 int hwgpio
= gpio_chip_hwgpio(desc
);
2845 int value
= value_array
[i
];
2847 if (!raw
&& test_bit(FLAG_ACTIVE_LOW
, &desc
->flags
))
2849 trace_gpio_value(desc_to_gpio(desc
), 0, value
);
2851 * collect all normal outputs belonging to the same chip
2852 * open drain and open source outputs are set individually
2854 if (test_bit(FLAG_OPEN_DRAIN
, &desc
->flags
) && !raw
) {
2855 gpio_set_open_drain_value_commit(desc
, value
);
2856 } else if (test_bit(FLAG_OPEN_SOURCE
, &desc
->flags
) && !raw
) {
2857 gpio_set_open_source_value_commit(desc
, value
);
2859 __set_bit(hwgpio
, mask
);
2861 __set_bit(hwgpio
, bits
);
2863 __clear_bit(hwgpio
, bits
);
2867 } while ((i
< array_size
) &&
2868 (desc_array
[i
]->gdev
->chip
== chip
));
2869 /* push collected bits to outputs */
2871 gpio_chip_set_multiple(chip
, mask
, bits
);
2876 * gpiod_set_raw_value() - assign a gpio's raw value
2877 * @desc: gpio whose value will be assigned
2878 * @value: value to assign
2880 * Set the raw value of the GPIO, i.e. the value of its physical line without
2881 * regard for its ACTIVE_LOW status.
2883 * This function should be called from contexts where we cannot sleep, and will
2884 * complain if the GPIO chip functions potentially sleep.
2886 void gpiod_set_raw_value(struct gpio_desc
*desc
, int value
)
2888 VALIDATE_DESC_VOID(desc
);
2889 /* Should be using gpiod_set_value_cansleep() */
2890 WARN_ON(desc
->gdev
->chip
->can_sleep
);
2891 gpiod_set_raw_value_commit(desc
, value
);
2893 EXPORT_SYMBOL_GPL(gpiod_set_raw_value
);
2896 * gpiod_set_value() - assign a gpio's value
2897 * @desc: gpio whose value will be assigned
2898 * @value: value to assign
2900 * Set the logical value of the GPIO, i.e. taking its ACTIVE_LOW,
2901 * OPEN_DRAIN and OPEN_SOURCE flags into account.
2903 * This function should be called from contexts where we cannot sleep, and will
2904 * complain if the GPIO chip functions potentially sleep.
2906 void gpiod_set_value(struct gpio_desc
*desc
, int value
)
2908 VALIDATE_DESC_VOID(desc
);
2909 /* Should be using gpiod_set_value_cansleep() */
2910 WARN_ON(desc
->gdev
->chip
->can_sleep
);
2911 if (test_bit(FLAG_ACTIVE_LOW
, &desc
->flags
))
2913 if (test_bit(FLAG_OPEN_DRAIN
, &desc
->flags
))
2914 gpio_set_open_drain_value_commit(desc
, value
);
2915 else if (test_bit(FLAG_OPEN_SOURCE
, &desc
->flags
))
2916 gpio_set_open_source_value_commit(desc
, value
);
2918 gpiod_set_raw_value_commit(desc
, value
);
2920 EXPORT_SYMBOL_GPL(gpiod_set_value
);
2923 * gpiod_set_raw_array_value() - assign values to an array of GPIOs
2924 * @array_size: number of elements in the descriptor / value arrays
2925 * @desc_array: array of GPIO descriptors whose values will be assigned
2926 * @value_array: array of values to assign
2928 * Set the raw values of the GPIOs, i.e. the values of the physical lines
2929 * without regard for their ACTIVE_LOW status.
2931 * This function should be called from contexts where we cannot sleep, and will
2932 * complain if the GPIO chip functions potentially sleep.
2934 void gpiod_set_raw_array_value(unsigned int array_size
,
2935 struct gpio_desc
**desc_array
, int *value_array
)
2939 gpiod_set_array_value_complex(true, false, array_size
, desc_array
,
2942 EXPORT_SYMBOL_GPL(gpiod_set_raw_array_value
);
2945 * gpiod_set_array_value() - assign values to an array of GPIOs
2946 * @array_size: number of elements in the descriptor / value arrays
2947 * @desc_array: array of GPIO descriptors whose values will be assigned
2948 * @value_array: array of values to assign
2950 * Set the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status
2953 * This function should be called from contexts where we cannot sleep, and will
2954 * complain if the GPIO chip functions potentially sleep.
2956 void gpiod_set_array_value(unsigned int array_size
,
2957 struct gpio_desc
**desc_array
, int *value_array
)
2961 gpiod_set_array_value_complex(false, false, array_size
, desc_array
,
2964 EXPORT_SYMBOL_GPL(gpiod_set_array_value
);
2967 * gpiod_cansleep() - report whether gpio value access may sleep
2968 * @desc: gpio to check
2971 int gpiod_cansleep(const struct gpio_desc
*desc
)
2973 VALIDATE_DESC(desc
);
2974 return desc
->gdev
->chip
->can_sleep
;
2976 EXPORT_SYMBOL_GPL(gpiod_cansleep
);
2979 * gpiod_to_irq() - return the IRQ corresponding to a GPIO
2980 * @desc: gpio whose IRQ will be returned (already requested)
2982 * Return the IRQ corresponding to the passed GPIO, or an error code in case of
2985 int gpiod_to_irq(const struct gpio_desc
*desc
)
2987 struct gpio_chip
*chip
;
2991 * Cannot VALIDATE_DESC() here as gpiod_to_irq() consumer semantics
2992 * requires this function to not return zero on an invalid descriptor
2993 * but rather a negative error number.
2995 if (!desc
|| IS_ERR(desc
) || !desc
->gdev
|| !desc
->gdev
->chip
)
2998 chip
= desc
->gdev
->chip
;
2999 offset
= gpio_chip_hwgpio(desc
);
3001 int retirq
= chip
->to_irq(chip
, offset
);
3003 /* Zero means NO_IRQ */
3011 EXPORT_SYMBOL_GPL(gpiod_to_irq
);
3014 * gpiochip_lock_as_irq() - lock a GPIO to be used as IRQ
3015 * @chip: the chip the GPIO to lock belongs to
3016 * @offset: the offset of the GPIO to lock as IRQ
3018 * This is used directly by GPIO drivers that want to lock down
3019 * a certain GPIO line to be used for IRQs.
3021 int gpiochip_lock_as_irq(struct gpio_chip
*chip
, unsigned int offset
)
3023 struct gpio_desc
*desc
;
3025 desc
= gpiochip_get_desc(chip
, offset
);
3027 return PTR_ERR(desc
);
3030 * If it's fast: flush the direction setting if something changed
3033 if (!chip
->can_sleep
&& chip
->get_direction
) {
3034 int dir
= chip
->get_direction(chip
, offset
);
3037 clear_bit(FLAG_IS_OUT
, &desc
->flags
);
3039 set_bit(FLAG_IS_OUT
, &desc
->flags
);
3042 if (test_bit(FLAG_IS_OUT
, &desc
->flags
)) {
3044 "%s: tried to flag a GPIO set as output for IRQ\n",
3049 set_bit(FLAG_USED_AS_IRQ
, &desc
->flags
);
3052 * If the consumer has not set up a label (such as when the
3053 * IRQ is referenced from .to_irq()) we set up a label here
3054 * so it is clear this is used as an interrupt.
3057 desc_set_label(desc
, "interrupt");
3061 EXPORT_SYMBOL_GPL(gpiochip_lock_as_irq
);
3064 * gpiochip_unlock_as_irq() - unlock a GPIO used as IRQ
3065 * @chip: the chip the GPIO to lock belongs to
3066 * @offset: the offset of the GPIO to lock as IRQ
3068 * This is used directly by GPIO drivers that want to indicate
3069 * that a certain GPIO is no longer used exclusively for IRQ.
3071 void gpiochip_unlock_as_irq(struct gpio_chip
*chip
, unsigned int offset
)
3073 struct gpio_desc
*desc
;
3075 desc
= gpiochip_get_desc(chip
, offset
);
3079 clear_bit(FLAG_USED_AS_IRQ
, &desc
->flags
);
3081 /* If we only had this marking, erase it */
3082 if (desc
->label
&& !strcmp(desc
->label
, "interrupt"))
3083 desc_set_label(desc
, NULL
);
3085 EXPORT_SYMBOL_GPL(gpiochip_unlock_as_irq
);
3087 bool gpiochip_line_is_irq(struct gpio_chip
*chip
, unsigned int offset
)
3089 if (offset
>= chip
->ngpio
)
3092 return test_bit(FLAG_USED_AS_IRQ
, &chip
->gpiodev
->descs
[offset
].flags
);
3094 EXPORT_SYMBOL_GPL(gpiochip_line_is_irq
);
3096 bool gpiochip_line_is_open_drain(struct gpio_chip
*chip
, unsigned int offset
)
3098 if (offset
>= chip
->ngpio
)
3101 return test_bit(FLAG_OPEN_DRAIN
, &chip
->gpiodev
->descs
[offset
].flags
);
3103 EXPORT_SYMBOL_GPL(gpiochip_line_is_open_drain
);
3105 bool gpiochip_line_is_open_source(struct gpio_chip
*chip
, unsigned int offset
)
3107 if (offset
>= chip
->ngpio
)
3110 return test_bit(FLAG_OPEN_SOURCE
, &chip
->gpiodev
->descs
[offset
].flags
);
3112 EXPORT_SYMBOL_GPL(gpiochip_line_is_open_source
);
3114 bool gpiochip_line_is_persistent(struct gpio_chip
*chip
, unsigned int offset
)
3116 if (offset
>= chip
->ngpio
)
3119 return !test_bit(FLAG_SLEEP_MAY_LOSE_VALUE
,
3120 &chip
->gpiodev
->descs
[offset
].flags
);
3122 EXPORT_SYMBOL_GPL(gpiochip_line_is_persistent
);
3125 * gpiod_get_raw_value_cansleep() - return a gpio's raw value
3126 * @desc: gpio whose value will be returned
3128 * Return the GPIO's raw value, i.e. the value of the physical line disregarding
3129 * its ACTIVE_LOW status, or negative errno on failure.
3131 * This function is to be called from contexts that can sleep.
3133 int gpiod_get_raw_value_cansleep(const struct gpio_desc
*desc
)
3135 might_sleep_if(extra_checks
);
3136 VALIDATE_DESC(desc
);
3137 return gpiod_get_raw_value_commit(desc
);
3139 EXPORT_SYMBOL_GPL(gpiod_get_raw_value_cansleep
);
3142 * gpiod_get_value_cansleep() - return a gpio's value
3143 * @desc: gpio whose value will be returned
3145 * Return the GPIO's logical value, i.e. taking the ACTIVE_LOW status into
3146 * account, or negative errno on failure.
3148 * This function is to be called from contexts that can sleep.
3150 int gpiod_get_value_cansleep(const struct gpio_desc
*desc
)
3154 might_sleep_if(extra_checks
);
3155 VALIDATE_DESC(desc
);
3156 value
= gpiod_get_raw_value_commit(desc
);
3160 if (test_bit(FLAG_ACTIVE_LOW
, &desc
->flags
))
3165 EXPORT_SYMBOL_GPL(gpiod_get_value_cansleep
);
3168 * gpiod_get_raw_array_value_cansleep() - read raw values from an array of GPIOs
3169 * @array_size: number of elements in the descriptor / value arrays
3170 * @desc_array: array of GPIO descriptors whose values will be read
3171 * @value_array: array to store the read values
3173 * Read the raw values of the GPIOs, i.e. the values of the physical lines
3174 * without regard for their ACTIVE_LOW status. Return 0 in case of success,
3175 * else an error code.
3177 * This function is to be called from contexts that can sleep.
3179 int gpiod_get_raw_array_value_cansleep(unsigned int array_size
,
3180 struct gpio_desc
**desc_array
,
3183 might_sleep_if(extra_checks
);
3186 return gpiod_get_array_value_complex(true, true, array_size
,
3187 desc_array
, value_array
);
3189 EXPORT_SYMBOL_GPL(gpiod_get_raw_array_value_cansleep
);
3192 * gpiod_get_array_value_cansleep() - read values from an array of GPIOs
3193 * @array_size: number of elements in the descriptor / value arrays
3194 * @desc_array: array of GPIO descriptors whose values will be read
3195 * @value_array: array to store the read values
3197 * Read the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status
3198 * into account. Return 0 in case of success, else an error code.
3200 * This function is to be called from contexts that can sleep.
3202 int gpiod_get_array_value_cansleep(unsigned int array_size
,
3203 struct gpio_desc
**desc_array
,
3206 might_sleep_if(extra_checks
);
3209 return gpiod_get_array_value_complex(false, true, array_size
,
3210 desc_array
, value_array
);
3212 EXPORT_SYMBOL_GPL(gpiod_get_array_value_cansleep
);
3215 * gpiod_set_raw_value_cansleep() - assign a gpio's raw value
3216 * @desc: gpio whose value will be assigned
3217 * @value: value to assign
3219 * Set the raw value of the GPIO, i.e. the value of its physical line without
3220 * regard for its ACTIVE_LOW status.
3222 * This function is to be called from contexts that can sleep.
3224 void gpiod_set_raw_value_cansleep(struct gpio_desc
*desc
, int value
)
3226 might_sleep_if(extra_checks
);
3227 VALIDATE_DESC_VOID(desc
);
3228 gpiod_set_raw_value_commit(desc
, value
);
3230 EXPORT_SYMBOL_GPL(gpiod_set_raw_value_cansleep
);
3233 * gpiod_set_value_cansleep() - assign a gpio's value
3234 * @desc: gpio whose value will be assigned
3235 * @value: value to assign
3237 * Set the logical value of the GPIO, i.e. taking its ACTIVE_LOW status into
3240 * This function is to be called from contexts that can sleep.
3242 void gpiod_set_value_cansleep(struct gpio_desc
*desc
, int value
)
3244 might_sleep_if(extra_checks
);
3245 VALIDATE_DESC_VOID(desc
);
3246 if (test_bit(FLAG_ACTIVE_LOW
, &desc
->flags
))
3248 gpiod_set_raw_value_commit(desc
, value
);
3250 EXPORT_SYMBOL_GPL(gpiod_set_value_cansleep
);
3253 * gpiod_set_raw_array_value_cansleep() - assign values to an array of GPIOs
3254 * @array_size: number of elements in the descriptor / value arrays
3255 * @desc_array: array of GPIO descriptors whose values will be assigned
3256 * @value_array: array of values to assign
3258 * Set the raw values of the GPIOs, i.e. the values of the physical lines
3259 * without regard for their ACTIVE_LOW status.
3261 * This function is to be called from contexts that can sleep.
3263 void gpiod_set_raw_array_value_cansleep(unsigned int array_size
,
3264 struct gpio_desc
**desc_array
,
3267 might_sleep_if(extra_checks
);
3270 gpiod_set_array_value_complex(true, true, array_size
, desc_array
,
3273 EXPORT_SYMBOL_GPL(gpiod_set_raw_array_value_cansleep
);
3276 * gpiod_add_lookup_tables() - register GPIO device consumers
3277 * @tables: list of tables of consumers to register
3278 * @n: number of tables in the list
3280 void gpiod_add_lookup_tables(struct gpiod_lookup_table
**tables
, size_t n
)
3284 mutex_lock(&gpio_lookup_lock
);
3286 for (i
= 0; i
< n
; i
++)
3287 list_add_tail(&tables
[i
]->list
, &gpio_lookup_list
);
3289 mutex_unlock(&gpio_lookup_lock
);
3293 * gpiod_set_array_value_cansleep() - assign values to an array of GPIOs
3294 * @array_size: number of elements in the descriptor / value arrays
3295 * @desc_array: array of GPIO descriptors whose values will be assigned
3296 * @value_array: array of values to assign
3298 * Set the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status
3301 * This function is to be called from contexts that can sleep.
3303 void gpiod_set_array_value_cansleep(unsigned int array_size
,
3304 struct gpio_desc
**desc_array
,
3307 might_sleep_if(extra_checks
);
3310 gpiod_set_array_value_complex(false, true, array_size
, desc_array
,
3313 EXPORT_SYMBOL_GPL(gpiod_set_array_value_cansleep
);
3316 * gpiod_add_lookup_table() - register GPIO device consumers
3317 * @table: table of consumers to register
3319 void gpiod_add_lookup_table(struct gpiod_lookup_table
*table
)
3321 mutex_lock(&gpio_lookup_lock
);
3323 list_add_tail(&table
->list
, &gpio_lookup_list
);
3325 mutex_unlock(&gpio_lookup_lock
);
3327 EXPORT_SYMBOL_GPL(gpiod_add_lookup_table
);
3330 * gpiod_remove_lookup_table() - unregister GPIO device consumers
3331 * @table: table of consumers to unregister
3333 void gpiod_remove_lookup_table(struct gpiod_lookup_table
*table
)
3335 mutex_lock(&gpio_lookup_lock
);
3337 list_del(&table
->list
);
3339 mutex_unlock(&gpio_lookup_lock
);
3341 EXPORT_SYMBOL_GPL(gpiod_remove_lookup_table
);
3343 static struct gpiod_lookup_table
*gpiod_find_lookup_table(struct device
*dev
)
3345 const char *dev_id
= dev
? dev_name(dev
) : NULL
;
3346 struct gpiod_lookup_table
*table
;
3348 mutex_lock(&gpio_lookup_lock
);
3350 list_for_each_entry(table
, &gpio_lookup_list
, list
) {
3351 if (table
->dev_id
&& dev_id
) {
3353 * Valid strings on both ends, must be identical to have
3356 if (!strcmp(table
->dev_id
, dev_id
))
3360 * One of the pointers is NULL, so both must be to have
3363 if (dev_id
== table
->dev_id
)
3370 mutex_unlock(&gpio_lookup_lock
);
3374 static struct gpio_desc
*gpiod_find(struct device
*dev
, const char *con_id
,
3376 enum gpio_lookup_flags
*flags
)
3378 struct gpio_desc
*desc
= ERR_PTR(-ENOENT
);
3379 struct gpiod_lookup_table
*table
;
3380 struct gpiod_lookup
*p
;
3382 table
= gpiod_find_lookup_table(dev
);
3386 for (p
= &table
->table
[0]; p
->chip_label
; p
++) {
3387 struct gpio_chip
*chip
;
3389 /* idx must always match exactly */
3393 /* If the lookup entry has a con_id, require exact match */
3394 if (p
->con_id
&& (!con_id
|| strcmp(p
->con_id
, con_id
)))
3397 chip
= find_chip_by_name(p
->chip_label
);
3400 dev_err(dev
, "cannot find GPIO chip %s\n",
3402 return ERR_PTR(-ENODEV
);
3405 if (chip
->ngpio
<= p
->chip_hwnum
) {
3407 "requested GPIO %d is out of range [0..%d] for chip %s\n",
3408 idx
, chip
->ngpio
, chip
->label
);
3409 return ERR_PTR(-EINVAL
);
3412 desc
= gpiochip_get_desc(chip
, p
->chip_hwnum
);
3421 static int dt_gpio_count(struct device
*dev
, const char *con_id
)
3427 for (i
= 0; i
< ARRAY_SIZE(gpio_suffixes
); i
++) {
3429 snprintf(propname
, sizeof(propname
), "%s-%s",
3430 con_id
, gpio_suffixes
[i
]);
3432 snprintf(propname
, sizeof(propname
), "%s",
3435 ret
= of_gpio_named_count(dev
->of_node
, propname
);
3439 return ret
? ret
: -ENOENT
;
3442 static int platform_gpio_count(struct device
*dev
, const char *con_id
)
3444 struct gpiod_lookup_table
*table
;
3445 struct gpiod_lookup
*p
;
3446 unsigned int count
= 0;
3448 table
= gpiod_find_lookup_table(dev
);
3452 for (p
= &table
->table
[0]; p
->chip_label
; p
++) {
3453 if ((con_id
&& p
->con_id
&& !strcmp(con_id
, p
->con_id
)) ||
3454 (!con_id
&& !p
->con_id
))
3464 * gpiod_count - return the number of GPIOs associated with a device / function
3465 * or -ENOENT if no GPIO has been assigned to the requested function
3466 * @dev: GPIO consumer, can be NULL for system-global GPIOs
3467 * @con_id: function within the GPIO consumer
3469 int gpiod_count(struct device
*dev
, const char *con_id
)
3471 int count
= -ENOENT
;
3473 if (IS_ENABLED(CONFIG_OF
) && dev
&& dev
->of_node
)
3474 count
= dt_gpio_count(dev
, con_id
);
3475 else if (IS_ENABLED(CONFIG_ACPI
) && dev
&& ACPI_HANDLE(dev
))
3476 count
= acpi_gpio_count(dev
, con_id
);
3479 count
= platform_gpio_count(dev
, con_id
);
3483 EXPORT_SYMBOL_GPL(gpiod_count
);
3486 * gpiod_get - obtain a GPIO for a given GPIO function
3487 * @dev: GPIO consumer, can be NULL for system-global GPIOs
3488 * @con_id: function within the GPIO consumer
3489 * @flags: optional GPIO initialization flags
3491 * Return the GPIO descriptor corresponding to the function con_id of device
3492 * dev, -ENOENT if no GPIO has been assigned to the requested function, or
3493 * another IS_ERR() code if an error occurred while trying to acquire the GPIO.
3495 struct gpio_desc
*__must_check
gpiod_get(struct device
*dev
, const char *con_id
,
3496 enum gpiod_flags flags
)
3498 return gpiod_get_index(dev
, con_id
, 0, flags
);
3500 EXPORT_SYMBOL_GPL(gpiod_get
);
3503 * gpiod_get_optional - obtain an optional GPIO for a given GPIO function
3504 * @dev: GPIO consumer, can be NULL for system-global GPIOs
3505 * @con_id: function within the GPIO consumer
3506 * @flags: optional GPIO initialization flags
3508 * This is equivalent to gpiod_get(), except that when no GPIO was assigned to
3509 * the requested function it will return NULL. This is convenient for drivers
3510 * that need to handle optional GPIOs.
3512 struct gpio_desc
*__must_check
gpiod_get_optional(struct device
*dev
,
3514 enum gpiod_flags flags
)
3516 return gpiod_get_index_optional(dev
, con_id
, 0, flags
);
3518 EXPORT_SYMBOL_GPL(gpiod_get_optional
);
3522 * gpiod_configure_flags - helper function to configure a given GPIO
3523 * @desc: gpio whose value will be assigned
3524 * @con_id: function within the GPIO consumer
3525 * @lflags: gpio_lookup_flags - returned from of_find_gpio() or
3527 * @dflags: gpiod_flags - optional GPIO initialization flags
3529 * Return 0 on success, -ENOENT if no GPIO has been assigned to the
3530 * requested function and/or index, or another IS_ERR() code if an error
3531 * occurred while trying to acquire the GPIO.
3533 int gpiod_configure_flags(struct gpio_desc
*desc
, const char *con_id
,
3534 unsigned long lflags
, enum gpiod_flags dflags
)
3538 if (lflags
& GPIO_ACTIVE_LOW
)
3539 set_bit(FLAG_ACTIVE_LOW
, &desc
->flags
);
3541 if (lflags
& GPIO_OPEN_DRAIN
)
3542 set_bit(FLAG_OPEN_DRAIN
, &desc
->flags
);
3543 else if (dflags
& GPIOD_FLAGS_BIT_OPEN_DRAIN
) {
3545 * This enforces open drain mode from the consumer side.
3546 * This is necessary for some busses like I2C, but the lookup
3547 * should *REALLY* have specified them as open drain in the
3548 * first place, so print a little warning here.
3550 set_bit(FLAG_OPEN_DRAIN
, &desc
->flags
);
3552 "enforced open drain please flag it properly in DT/ACPI DSDT/board file\n");
3555 if (lflags
& GPIO_OPEN_SOURCE
)
3556 set_bit(FLAG_OPEN_SOURCE
, &desc
->flags
);
3557 if (lflags
& GPIO_SLEEP_MAY_LOSE_VALUE
)
3558 set_bit(FLAG_SLEEP_MAY_LOSE_VALUE
, &desc
->flags
);
3560 /* No particular flag request, return here... */
3561 if (!(dflags
& GPIOD_FLAGS_BIT_DIR_SET
)) {
3562 pr_debug("no flags found for %s\n", con_id
);
3567 if (dflags
& GPIOD_FLAGS_BIT_DIR_OUT
)
3568 status
= gpiod_direction_output(desc
,
3569 !!(dflags
& GPIOD_FLAGS_BIT_DIR_VAL
));
3571 status
= gpiod_direction_input(desc
);
3577 * gpiod_get_index - obtain a GPIO from a multi-index GPIO function
3578 * @dev: GPIO consumer, can be NULL for system-global GPIOs
3579 * @con_id: function within the GPIO consumer
3580 * @idx: index of the GPIO to obtain in the consumer
3581 * @flags: optional GPIO initialization flags
3583 * This variant of gpiod_get() allows to access GPIOs other than the first
3584 * defined one for functions that define several GPIOs.
3586 * Return a valid GPIO descriptor, -ENOENT if no GPIO has been assigned to the
3587 * requested function and/or index, or another IS_ERR() code if an error
3588 * occurred while trying to acquire the GPIO.
3590 struct gpio_desc
*__must_check
gpiod_get_index(struct device
*dev
,
3593 enum gpiod_flags flags
)
3595 struct gpio_desc
*desc
= NULL
;
3597 enum gpio_lookup_flags lookupflags
= 0;
3599 dev_dbg(dev
, "GPIO lookup for consumer %s\n", con_id
);
3602 /* Using device tree? */
3603 if (IS_ENABLED(CONFIG_OF
) && dev
->of_node
) {
3604 dev_dbg(dev
, "using device tree for GPIO lookup\n");
3605 desc
= of_find_gpio(dev
, con_id
, idx
, &lookupflags
);
3606 } else if (ACPI_COMPANION(dev
)) {
3607 dev_dbg(dev
, "using ACPI for GPIO lookup\n");
3608 desc
= acpi_find_gpio(dev
, con_id
, idx
, &flags
, &lookupflags
);
3613 * Either we are not using DT or ACPI, or their lookup did not return
3614 * a result. In that case, use platform lookup as a fallback.
3616 if (!desc
|| desc
== ERR_PTR(-ENOENT
)) {
3617 dev_dbg(dev
, "using lookup tables for GPIO lookup\n");
3618 desc
= gpiod_find(dev
, con_id
, idx
, &lookupflags
);
3622 dev_dbg(dev
, "lookup for GPIO %s failed\n", con_id
);
3626 status
= gpiod_request(desc
, con_id
);
3628 return ERR_PTR(status
);
3630 status
= gpiod_configure_flags(desc
, con_id
, lookupflags
, flags
);
3632 dev_dbg(dev
, "setup of GPIO %s failed\n", con_id
);
3634 return ERR_PTR(status
);
3639 EXPORT_SYMBOL_GPL(gpiod_get_index
);
3642 * fwnode_get_named_gpiod - obtain a GPIO from firmware node
3643 * @fwnode: handle of the firmware node
3644 * @propname: name of the firmware property representing the GPIO
3645 * @index: index of the GPIO to obtain in the consumer
3646 * @dflags: GPIO initialization flags
3647 * @label: label to attach to the requested GPIO
3649 * This function can be used for drivers that get their configuration
3652 * Function properly finds the corresponding GPIO using whatever is the
3653 * underlying firmware interface and then makes sure that the GPIO
3654 * descriptor is requested before it is returned to the caller.
3657 * On successful request the GPIO pin is configured in accordance with
3660 * In case of error an ERR_PTR() is returned.
3662 struct gpio_desc
*fwnode_get_named_gpiod(struct fwnode_handle
*fwnode
,
3663 const char *propname
, int index
,
3664 enum gpiod_flags dflags
,
3667 struct gpio_desc
*desc
= ERR_PTR(-ENODEV
);
3668 unsigned long lflags
= 0;
3669 bool active_low
= false;
3670 bool single_ended
= false;
3671 bool open_drain
= false;
3675 return ERR_PTR(-EINVAL
);
3677 if (is_of_node(fwnode
)) {
3678 enum of_gpio_flags flags
;
3680 desc
= of_get_named_gpiod_flags(to_of_node(fwnode
), propname
,
3682 if (!IS_ERR(desc
)) {
3683 active_low
= flags
& OF_GPIO_ACTIVE_LOW
;
3684 single_ended
= flags
& OF_GPIO_SINGLE_ENDED
;
3685 open_drain
= flags
& OF_GPIO_OPEN_DRAIN
;
3687 } else if (is_acpi_node(fwnode
)) {
3688 struct acpi_gpio_info info
;
3690 desc
= acpi_node_get_gpiod(fwnode
, propname
, index
, &info
);
3691 if (!IS_ERR(desc
)) {
3692 active_low
= info
.polarity
== GPIO_ACTIVE_LOW
;
3693 ret
= acpi_gpio_update_gpiod_flags(&dflags
, info
.flags
);
3695 pr_debug("Override GPIO initialization flags\n");
3702 ret
= gpiod_request(desc
, label
);
3704 return ERR_PTR(ret
);
3707 lflags
|= GPIO_ACTIVE_LOW
;
3711 lflags
|= GPIO_OPEN_DRAIN
;
3713 lflags
|= GPIO_OPEN_SOURCE
;
3716 ret
= gpiod_configure_flags(desc
, propname
, lflags
, dflags
);
3719 return ERR_PTR(ret
);
3724 EXPORT_SYMBOL_GPL(fwnode_get_named_gpiod
);
3727 * gpiod_get_index_optional - obtain an optional GPIO from a multi-index GPIO
3729 * @dev: GPIO consumer, can be NULL for system-global GPIOs
3730 * @con_id: function within the GPIO consumer
3731 * @index: index of the GPIO to obtain in the consumer
3732 * @flags: optional GPIO initialization flags
3734 * This is equivalent to gpiod_get_index(), except that when no GPIO with the
3735 * specified index was assigned to the requested function it will return NULL.
3736 * This is convenient for drivers that need to handle optional GPIOs.
3738 struct gpio_desc
*__must_check
gpiod_get_index_optional(struct device
*dev
,
3741 enum gpiod_flags flags
)
3743 struct gpio_desc
*desc
;
3745 desc
= gpiod_get_index(dev
, con_id
, index
, flags
);
3747 if (PTR_ERR(desc
) == -ENOENT
)
3753 EXPORT_SYMBOL_GPL(gpiod_get_index_optional
);
3756 * gpiod_hog - Hog the specified GPIO desc given the provided flags
3757 * @desc: gpio whose value will be assigned
3758 * @name: gpio line name
3759 * @lflags: gpio_lookup_flags - returned from of_find_gpio() or
3761 * @dflags: gpiod_flags - optional GPIO initialization flags
3763 int gpiod_hog(struct gpio_desc
*desc
, const char *name
,
3764 unsigned long lflags
, enum gpiod_flags dflags
)
3766 struct gpio_chip
*chip
;
3767 struct gpio_desc
*local_desc
;
3771 chip
= gpiod_to_chip(desc
);
3772 hwnum
= gpio_chip_hwgpio(desc
);
3774 local_desc
= gpiochip_request_own_desc(chip
, hwnum
, name
);
3775 if (IS_ERR(local_desc
)) {
3776 status
= PTR_ERR(local_desc
);
3777 pr_err("requesting hog GPIO %s (chip %s, offset %d) failed, %d\n",
3778 name
, chip
->label
, hwnum
, status
);
3782 status
= gpiod_configure_flags(desc
, name
, lflags
, dflags
);
3784 pr_err("setup of hog GPIO %s (chip %s, offset %d) failed, %d\n",
3785 name
, chip
->label
, hwnum
, status
);
3786 gpiochip_free_own_desc(desc
);
3790 /* Mark GPIO as hogged so it can be identified and removed later */
3791 set_bit(FLAG_IS_HOGGED
, &desc
->flags
);
3793 pr_info("GPIO line %d (%s) hogged as %s%s\n",
3794 desc_to_gpio(desc
), name
,
3795 (dflags
&GPIOD_FLAGS_BIT_DIR_OUT
) ? "output" : "input",
3796 (dflags
&GPIOD_FLAGS_BIT_DIR_OUT
) ?
3797 (dflags
&GPIOD_FLAGS_BIT_DIR_VAL
) ? "/high" : "/low":"");
3803 * gpiochip_free_hogs - Scan gpio-controller chip and release GPIO hog
3804 * @chip: gpio chip to act on
3806 * This is only used by of_gpiochip_remove to free hogged gpios
3808 static void gpiochip_free_hogs(struct gpio_chip
*chip
)
3812 for (id
= 0; id
< chip
->ngpio
; id
++) {
3813 if (test_bit(FLAG_IS_HOGGED
, &chip
->gpiodev
->descs
[id
].flags
))
3814 gpiochip_free_own_desc(&chip
->gpiodev
->descs
[id
]);
3819 * gpiod_get_array - obtain multiple GPIOs from a multi-index GPIO function
3820 * @dev: GPIO consumer, can be NULL for system-global GPIOs
3821 * @con_id: function within the GPIO consumer
3822 * @flags: optional GPIO initialization flags
3824 * This function acquires all the GPIOs defined under a given function.
3826 * Return a struct gpio_descs containing an array of descriptors, -ENOENT if
3827 * no GPIO has been assigned to the requested function, or another IS_ERR()
3828 * code if an error occurred while trying to acquire the GPIOs.
3830 struct gpio_descs
*__must_check
gpiod_get_array(struct device
*dev
,
3832 enum gpiod_flags flags
)
3834 struct gpio_desc
*desc
;
3835 struct gpio_descs
*descs
;
3838 count
= gpiod_count(dev
, con_id
);
3840 return ERR_PTR(count
);
3842 descs
= kzalloc(sizeof(*descs
) + sizeof(descs
->desc
[0]) * count
,
3845 return ERR_PTR(-ENOMEM
);
3847 for (descs
->ndescs
= 0; descs
->ndescs
< count
; ) {
3848 desc
= gpiod_get_index(dev
, con_id
, descs
->ndescs
, flags
);
3850 gpiod_put_array(descs
);
3851 return ERR_CAST(desc
);
3853 descs
->desc
[descs
->ndescs
] = desc
;
3858 EXPORT_SYMBOL_GPL(gpiod_get_array
);
3861 * gpiod_get_array_optional - obtain multiple GPIOs from a multi-index GPIO
3863 * @dev: GPIO consumer, can be NULL for system-global GPIOs
3864 * @con_id: function within the GPIO consumer
3865 * @flags: optional GPIO initialization flags
3867 * This is equivalent to gpiod_get_array(), except that when no GPIO was
3868 * assigned to the requested function it will return NULL.
3870 struct gpio_descs
*__must_check
gpiod_get_array_optional(struct device
*dev
,
3872 enum gpiod_flags flags
)
3874 struct gpio_descs
*descs
;
3876 descs
= gpiod_get_array(dev
, con_id
, flags
);
3877 if (IS_ERR(descs
) && (PTR_ERR(descs
) == -ENOENT
))
3882 EXPORT_SYMBOL_GPL(gpiod_get_array_optional
);
3885 * gpiod_put - dispose of a GPIO descriptor
3886 * @desc: GPIO descriptor to dispose of
3888 * No descriptor can be used after gpiod_put() has been called on it.
3890 void gpiod_put(struct gpio_desc
*desc
)
3894 EXPORT_SYMBOL_GPL(gpiod_put
);
3897 * gpiod_put_array - dispose of multiple GPIO descriptors
3898 * @descs: struct gpio_descs containing an array of descriptors
3900 void gpiod_put_array(struct gpio_descs
*descs
)
3904 for (i
= 0; i
< descs
->ndescs
; i
++)
3905 gpiod_put(descs
->desc
[i
]);
3909 EXPORT_SYMBOL_GPL(gpiod_put_array
);
3911 static int __init
gpiolib_dev_init(void)
3915 /* Register GPIO sysfs bus */
3916 ret
= bus_register(&gpio_bus_type
);
3918 pr_err("gpiolib: could not register GPIO bus type\n");
3922 ret
= alloc_chrdev_region(&gpio_devt
, 0, GPIO_DEV_MAX
, "gpiochip");
3924 pr_err("gpiolib: failed to allocate char dev region\n");
3925 bus_unregister(&gpio_bus_type
);
3927 gpiolib_initialized
= true;
3928 gpiochip_setup_devs();
3932 core_initcall(gpiolib_dev_init
);
3934 #ifdef CONFIG_DEBUG_FS
3936 static void gpiolib_dbg_show(struct seq_file
*s
, struct gpio_device
*gdev
)
3939 struct gpio_chip
*chip
= gdev
->chip
;
3940 unsigned gpio
= gdev
->base
;
3941 struct gpio_desc
*gdesc
= &gdev
->descs
[0];
3945 for (i
= 0; i
< gdev
->ngpio
; i
++, gpio
++, gdesc
++) {
3946 if (!test_bit(FLAG_REQUESTED
, &gdesc
->flags
)) {
3948 seq_printf(s
, " gpio-%-3d (%-20.20s)\n",
3954 gpiod_get_direction(gdesc
);
3955 is_out
= test_bit(FLAG_IS_OUT
, &gdesc
->flags
);
3956 is_irq
= test_bit(FLAG_USED_AS_IRQ
, &gdesc
->flags
);
3957 seq_printf(s
, " gpio-%-3d (%-20.20s|%-20.20s) %s %s %s",
3958 gpio
, gdesc
->name
? gdesc
->name
: "", gdesc
->label
,
3959 is_out
? "out" : "in ",
3961 ? (chip
->get(chip
, i
) ? "hi" : "lo")
3963 is_irq
? "IRQ" : " ");
3964 seq_printf(s
, "\n");
3968 static void *gpiolib_seq_start(struct seq_file
*s
, loff_t
*pos
)
3970 unsigned long flags
;
3971 struct gpio_device
*gdev
= NULL
;
3972 loff_t index
= *pos
;
3976 spin_lock_irqsave(&gpio_lock
, flags
);
3977 list_for_each_entry(gdev
, &gpio_devices
, list
)
3979 spin_unlock_irqrestore(&gpio_lock
, flags
);
3982 spin_unlock_irqrestore(&gpio_lock
, flags
);
3987 static void *gpiolib_seq_next(struct seq_file
*s
, void *v
, loff_t
*pos
)
3989 unsigned long flags
;
3990 struct gpio_device
*gdev
= v
;
3993 spin_lock_irqsave(&gpio_lock
, flags
);
3994 if (list_is_last(&gdev
->list
, &gpio_devices
))
3997 ret
= list_entry(gdev
->list
.next
, struct gpio_device
, list
);
3998 spin_unlock_irqrestore(&gpio_lock
, flags
);
4006 static void gpiolib_seq_stop(struct seq_file
*s
, void *v
)
4010 static int gpiolib_seq_show(struct seq_file
*s
, void *v
)
4012 struct gpio_device
*gdev
= v
;
4013 struct gpio_chip
*chip
= gdev
->chip
;
4014 struct device
*parent
;
4017 seq_printf(s
, "%s%s: (dangling chip)", (char *)s
->private,
4018 dev_name(&gdev
->dev
));
4022 seq_printf(s
, "%s%s: GPIOs %d-%d", (char *)s
->private,
4023 dev_name(&gdev
->dev
),
4024 gdev
->base
, gdev
->base
+ gdev
->ngpio
- 1);
4025 parent
= chip
->parent
;
4027 seq_printf(s
, ", parent: %s/%s",
4028 parent
->bus
? parent
->bus
->name
: "no-bus",
4031 seq_printf(s
, ", %s", chip
->label
);
4032 if (chip
->can_sleep
)
4033 seq_printf(s
, ", can sleep");
4034 seq_printf(s
, ":\n");
4037 chip
->dbg_show(s
, chip
);
4039 gpiolib_dbg_show(s
, gdev
);
4044 static const struct seq_operations gpiolib_seq_ops
= {
4045 .start
= gpiolib_seq_start
,
4046 .next
= gpiolib_seq_next
,
4047 .stop
= gpiolib_seq_stop
,
4048 .show
= gpiolib_seq_show
,
4051 static int gpiolib_open(struct inode
*inode
, struct file
*file
)
4053 return seq_open(file
, &gpiolib_seq_ops
);
4056 static const struct file_operations gpiolib_operations
= {
4057 .owner
= THIS_MODULE
,
4058 .open
= gpiolib_open
,
4060 .llseek
= seq_lseek
,
4061 .release
= seq_release
,
4064 static int __init
gpiolib_debugfs_init(void)
4066 /* /sys/kernel/debug/gpio */
4067 (void) debugfs_create_file("gpio", S_IFREG
| S_IRUGO
,
4068 NULL
, NULL
, &gpiolib_operations
);
4071 subsys_initcall(gpiolib_debugfs_init
);
4073 #endif /* DEBUG_FS */