1 #include <linux/kernel.h>
2 #include <linux/module.h>
3 #include <linux/interrupt.h>
5 #include <linux/spinlock.h>
6 #include <linux/list.h>
7 #include <linux/device.h>
9 #include <linux/debugfs.h>
10 #include <linux/seq_file.h>
11 #include <linux/gpio.h>
12 #include <linux/of_gpio.h>
13 #include <linux/idr.h>
14 #include <linux/slab.h>
15 #include <linux/acpi.h>
16 #include <linux/gpio/driver.h>
17 #include <linux/gpio/machine.h>
18 #include <linux/pinctrl/consumer.h>
22 #define CREATE_TRACE_POINTS
23 #include <trace/events/gpio.h>
25 /* Implementation infrastructure for GPIO interfaces.
27 * The GPIO programming interface allows for inlining speed-critical
28 * get/set operations for common cases, so that access to SOC-integrated
29 * GPIOs can sometimes cost only an instruction or two per bit.
33 /* When debugging, extend minimal trust to callers and platform code.
34 * Also emit diagnostic messages that may help initial bringup, when
35 * board setup or driver bugs are most common.
37 * Otherwise, minimize overhead in what may be bitbanging codepaths.
40 #define extra_checks 1
42 #define extra_checks 0
45 /* gpio_lock prevents conflicts during gpio_desc[] table updates.
46 * While any GPIO is requested, its gpio_chip is not removable;
47 * each GPIO's "requested" flag serves as a lock and refcount.
49 DEFINE_SPINLOCK(gpio_lock
);
51 static DEFINE_MUTEX(gpio_lookup_lock
);
52 static LIST_HEAD(gpio_lookup_list
);
53 LIST_HEAD(gpio_chips
);
56 static void gpiochip_free_hogs(struct gpio_chip
*chip
);
57 static void gpiochip_irqchip_remove(struct gpio_chip
*gpiochip
);
60 static inline void desc_set_label(struct gpio_desc
*d
, const char *label
)
66 * Convert a GPIO number to its descriptor
68 struct gpio_desc
*gpio_to_desc(unsigned gpio
)
70 struct gpio_chip
*chip
;
73 spin_lock_irqsave(&gpio_lock
, flags
);
75 list_for_each_entry(chip
, &gpio_chips
, list
) {
76 if (chip
->base
<= gpio
&& chip
->base
+ chip
->ngpio
> gpio
) {
77 spin_unlock_irqrestore(&gpio_lock
, flags
);
78 return &chip
->desc
[gpio
- chip
->base
];
82 spin_unlock_irqrestore(&gpio_lock
, flags
);
84 if (!gpio_is_valid(gpio
))
85 WARN(1, "invalid GPIO %d\n", gpio
);
89 EXPORT_SYMBOL_GPL(gpio_to_desc
);
92 * Get the GPIO descriptor corresponding to the given hw number for this chip.
94 struct gpio_desc
*gpiochip_get_desc(struct gpio_chip
*chip
,
97 if (hwnum
>= chip
->ngpio
)
98 return ERR_PTR(-EINVAL
);
100 return &chip
->desc
[hwnum
];
104 * Convert a GPIO descriptor to the integer namespace.
105 * This should disappear in the future but is needed since we still
106 * use GPIO numbers for error messages and sysfs nodes
108 int desc_to_gpio(const struct gpio_desc
*desc
)
110 return desc
->chip
->base
+ (desc
- &desc
->chip
->desc
[0]);
112 EXPORT_SYMBOL_GPL(desc_to_gpio
);
116 * gpiod_to_chip - Return the GPIO chip to which a GPIO descriptor belongs
117 * @desc: descriptor to return the chip of
119 struct gpio_chip
*gpiod_to_chip(const struct gpio_desc
*desc
)
121 return desc
? desc
->chip
: NULL
;
123 EXPORT_SYMBOL_GPL(gpiod_to_chip
);
125 /* dynamic allocation of GPIOs, e.g. on a hotplugged device */
126 static int gpiochip_find_base(int ngpio
)
128 struct gpio_chip
*chip
;
129 int base
= ARCH_NR_GPIOS
- ngpio
;
131 list_for_each_entry_reverse(chip
, &gpio_chips
, list
) {
132 /* found a free space? */
133 if (chip
->base
+ chip
->ngpio
<= base
)
136 /* nope, check the space right before the chip */
137 base
= chip
->base
- ngpio
;
140 if (gpio_is_valid(base
)) {
141 pr_debug("%s: found new base at %d\n", __func__
, base
);
144 pr_err("%s: cannot find free range\n", __func__
);
150 * gpiod_get_direction - return the current direction of a GPIO
151 * @desc: GPIO to get the direction of
153 * Return GPIOF_DIR_IN or GPIOF_DIR_OUT, or an error code in case of error.
155 * This function may sleep if gpiod_cansleep() is true.
157 int gpiod_get_direction(struct gpio_desc
*desc
)
159 struct gpio_chip
*chip
;
161 int status
= -EINVAL
;
163 chip
= gpiod_to_chip(desc
);
164 offset
= gpio_chip_hwgpio(desc
);
166 if (!chip
->get_direction
)
169 status
= chip
->get_direction(chip
, offset
);
171 /* GPIOF_DIR_IN, or other positive */
173 clear_bit(FLAG_IS_OUT
, &desc
->flags
);
177 set_bit(FLAG_IS_OUT
, &desc
->flags
);
181 EXPORT_SYMBOL_GPL(gpiod_get_direction
);
184 * Add a new chip to the global chips list, keeping the list of chips sorted
187 * Return -EBUSY if the new chip overlaps with some other chip's integer
190 static int gpiochip_add_to_list(struct gpio_chip
*chip
)
192 struct list_head
*pos
;
193 struct gpio_chip
*_chip
;
196 /* find where to insert our chip */
197 list_for_each(pos
, &gpio_chips
) {
198 _chip
= list_entry(pos
, struct gpio_chip
, list
);
199 /* shall we insert before _chip? */
200 if (_chip
->base
>= chip
->base
+ chip
->ngpio
)
204 /* are we stepping on the chip right before? */
205 if (pos
!= &gpio_chips
&& pos
->prev
!= &gpio_chips
) {
206 _chip
= list_entry(pos
->prev
, struct gpio_chip
, list
);
207 if (_chip
->base
+ _chip
->ngpio
> chip
->base
) {
208 dev_err(chip
->parent
,
209 "GPIO integer space overlap, cannot add chip\n");
215 list_add_tail(&chip
->list
, pos
);
221 * Convert a GPIO name to its descriptor
223 static struct gpio_desc
*gpio_name_to_desc(const char * const name
)
225 struct gpio_chip
*chip
;
228 spin_lock_irqsave(&gpio_lock
, flags
);
230 list_for_each_entry(chip
, &gpio_chips
, list
) {
233 for (i
= 0; i
!= chip
->ngpio
; ++i
) {
234 struct gpio_desc
*gpio
= &chip
->desc
[i
];
239 if (!strcmp(gpio
->name
, name
)) {
240 spin_unlock_irqrestore(&gpio_lock
, flags
);
246 spin_unlock_irqrestore(&gpio_lock
, flags
);
252 * Takes the names from gc->names and checks if they are all unique. If they
253 * are, they are assigned to their gpio descriptors.
255 * Returns -EEXIST if one of the names is already used for a different GPIO.
257 static int gpiochip_set_desc_names(struct gpio_chip
*gc
)
264 /* First check all names if they are unique */
265 for (i
= 0; i
!= gc
->ngpio
; ++i
) {
266 struct gpio_desc
*gpio
;
268 gpio
= gpio_name_to_desc(gc
->names
[i
]);
270 dev_warn(gc
->parent
, "Detected name collision for "
275 /* Then add all names to the GPIO descriptors */
276 for (i
= 0; i
!= gc
->ngpio
; ++i
)
277 gc
->desc
[i
].name
= gc
->names
[i
];
283 * gpiochip_add() - register a gpio_chip
284 * @chip: the chip to register, with chip->base initialized
285 * Context: potentially before irqs will work
287 * Returns a negative errno if the chip can't be registered, such as
288 * because the chip->base is invalid or already associated with a
289 * different chip. Otherwise it returns zero as a success code.
291 * When gpiochip_add() is called very early during boot, so that GPIOs
292 * can be freely used, the chip->dev device must be registered before
293 * the gpio framework's arch_initcall(). Otherwise sysfs initialization
294 * for GPIOs will fail rudely.
296 * If chip->base is negative, this requests dynamic assignment of
297 * a range of valid GPIOs.
299 int gpiochip_add(struct gpio_chip
*chip
)
304 int base
= chip
->base
;
305 struct gpio_desc
*descs
;
307 descs
= kcalloc(chip
->ngpio
, sizeof(descs
[0]), GFP_KERNEL
);
311 spin_lock_irqsave(&gpio_lock
, flags
);
314 base
= gpiochip_find_base(chip
->ngpio
);
317 spin_unlock_irqrestore(&gpio_lock
, flags
);
323 status
= gpiochip_add_to_list(chip
);
325 spin_unlock_irqrestore(&gpio_lock
, flags
);
329 for (id
= 0; id
< chip
->ngpio
; id
++) {
330 struct gpio_desc
*desc
= &descs
[id
];
334 /* REVISIT: most hardware initializes GPIOs as inputs (often
335 * with pullups enabled) so power usage is minimized. Linux
336 * code should set the gpio direction first thing; but until
337 * it does, and in case chip->get_direction is not set, we may
338 * expose the wrong direction in sysfs.
340 desc
->flags
= !chip
->direction_input
? (1 << FLAG_IS_OUT
) : 0;
345 spin_unlock_irqrestore(&gpio_lock
, flags
);
347 #ifdef CONFIG_PINCTRL
348 INIT_LIST_HEAD(&chip
->pin_ranges
);
351 if (!chip
->owner
&& chip
->parent
&& chip
->parent
->driver
)
352 chip
->owner
= chip
->parent
->driver
->owner
;
354 status
= gpiochip_set_desc_names(chip
);
356 goto err_remove_from_list
;
358 status
= of_gpiochip_add(chip
);
360 goto err_remove_chip
;
362 acpi_gpiochip_add(chip
);
364 status
= gpiochip_sysfs_register(chip
);
366 goto err_remove_chip
;
368 pr_debug("%s: registered GPIOs %d to %d on device: %s\n", __func__
,
369 chip
->base
, chip
->base
+ chip
->ngpio
- 1,
370 chip
->label
? : "generic");
375 acpi_gpiochip_remove(chip
);
376 gpiochip_free_hogs(chip
);
377 of_gpiochip_remove(chip
);
378 err_remove_from_list
:
379 spin_lock_irqsave(&gpio_lock
, flags
);
380 list_del(&chip
->list
);
381 spin_unlock_irqrestore(&gpio_lock
, flags
);
386 /* failures here can mean systems won't boot... */
387 pr_err("%s: GPIOs %d..%d (%s) failed to register\n", __func__
,
388 chip
->base
, chip
->base
+ chip
->ngpio
- 1,
389 chip
->label
? : "generic");
392 EXPORT_SYMBOL_GPL(gpiochip_add
);
395 * gpiochip_remove() - unregister a gpio_chip
396 * @chip: the chip to unregister
398 * A gpio_chip with any GPIOs still requested may not be removed.
400 void gpiochip_remove(struct gpio_chip
*chip
)
402 struct gpio_desc
*desc
;
405 bool requested
= false;
407 gpiochip_sysfs_unregister(chip
);
409 gpiochip_irqchip_remove(chip
);
411 acpi_gpiochip_remove(chip
);
412 gpiochip_remove_pin_ranges(chip
);
413 gpiochip_free_hogs(chip
);
414 of_gpiochip_remove(chip
);
416 spin_lock_irqsave(&gpio_lock
, flags
);
417 for (id
= 0; id
< chip
->ngpio
; id
++) {
418 desc
= &chip
->desc
[id
];
420 if (test_bit(FLAG_REQUESTED
, &desc
->flags
))
423 list_del(&chip
->list
);
424 spin_unlock_irqrestore(&gpio_lock
, flags
);
427 dev_crit(chip
->parent
,
428 "REMOVING GPIOCHIP WITH GPIOS STILL REQUESTED\n");
433 EXPORT_SYMBOL_GPL(gpiochip_remove
);
436 * gpiochip_find() - iterator for locating a specific gpio_chip
437 * @data: data to pass to match function
438 * @callback: Callback function to check gpio_chip
440 * Similar to bus_find_device. It returns a reference to a gpio_chip as
441 * determined by a user supplied @match callback. The callback should return
442 * 0 if the device doesn't match and non-zero if it does. If the callback is
443 * non-zero, this function will return to the caller and not iterate over any
446 struct gpio_chip
*gpiochip_find(void *data
,
447 int (*match
)(struct gpio_chip
*chip
,
450 struct gpio_chip
*chip
;
453 spin_lock_irqsave(&gpio_lock
, flags
);
454 list_for_each_entry(chip
, &gpio_chips
, list
)
455 if (match(chip
, data
))
459 if (&chip
->list
== &gpio_chips
)
461 spin_unlock_irqrestore(&gpio_lock
, flags
);
465 EXPORT_SYMBOL_GPL(gpiochip_find
);
467 static int gpiochip_match_name(struct gpio_chip
*chip
, void *data
)
469 const char *name
= data
;
471 return !strcmp(chip
->label
, name
);
474 static struct gpio_chip
*find_chip_by_name(const char *name
)
476 return gpiochip_find((void *)name
, gpiochip_match_name
);
479 #ifdef CONFIG_GPIOLIB_IRQCHIP
482 * The following is irqchip helper code for gpiochips.
486 * gpiochip_set_chained_irqchip() - sets a chained irqchip to a gpiochip
487 * @gpiochip: the gpiochip to set the irqchip chain to
488 * @irqchip: the irqchip to chain to the gpiochip
489 * @parent_irq: the irq number corresponding to the parent IRQ for this
491 * @parent_handler: the parent interrupt handler for the accumulated IRQ
492 * coming out of the gpiochip. If the interrupt is nested rather than
493 * cascaded, pass NULL in this handler argument
495 void gpiochip_set_chained_irqchip(struct gpio_chip
*gpiochip
,
496 struct irq_chip
*irqchip
,
498 irq_flow_handler_t parent_handler
)
502 if (!gpiochip
->irqdomain
) {
503 chip_err(gpiochip
, "called %s before setting up irqchip\n",
508 if (parent_handler
) {
509 if (gpiochip
->can_sleep
) {
511 "you cannot have chained interrupts on a "
512 "chip that may sleep\n");
516 * The parent irqchip is already using the chip_data for this
517 * irqchip, so our callbacks simply use the handler_data.
519 irq_set_chained_handler_and_data(parent_irq
, parent_handler
,
522 gpiochip
->irq_parent
= parent_irq
;
525 /* Set the parent IRQ for all affected IRQs */
526 for (offset
= 0; offset
< gpiochip
->ngpio
; offset
++)
527 irq_set_parent(irq_find_mapping(gpiochip
->irqdomain
, offset
),
530 EXPORT_SYMBOL_GPL(gpiochip_set_chained_irqchip
);
533 * gpiochip_irq_map() - maps an IRQ into a GPIO irqchip
534 * @d: the irqdomain used by this irqchip
535 * @irq: the global irq number used by this GPIO irqchip irq
536 * @hwirq: the local IRQ/GPIO line offset on this gpiochip
538 * This function will set up the mapping for a certain IRQ line on a
539 * gpiochip by assigning the gpiochip as chip data, and using the irqchip
540 * stored inside the gpiochip.
542 static int gpiochip_irq_map(struct irq_domain
*d
, unsigned int irq
,
543 irq_hw_number_t hwirq
)
545 struct gpio_chip
*chip
= d
->host_data
;
547 irq_set_chip_data(irq
, chip
);
549 * This lock class tells lockdep that GPIO irqs are in a different
550 * category than their parents, so it won't report false recursion.
552 irq_set_lockdep_class(irq
, chip
->lock_key
);
553 irq_set_chip_and_handler(irq
, chip
->irqchip
, chip
->irq_handler
);
554 /* Chips that can sleep need nested thread handlers */
555 if (chip
->can_sleep
&& !chip
->irq_not_threaded
)
556 irq_set_nested_thread(irq
, 1);
557 irq_set_noprobe(irq
);
560 * No set-up of the hardware will happen if IRQ_TYPE_NONE
561 * is passed as default type.
563 if (chip
->irq_default_type
!= IRQ_TYPE_NONE
)
564 irq_set_irq_type(irq
, chip
->irq_default_type
);
569 static void gpiochip_irq_unmap(struct irq_domain
*d
, unsigned int irq
)
571 struct gpio_chip
*chip
= d
->host_data
;
574 irq_set_nested_thread(irq
, 0);
575 irq_set_chip_and_handler(irq
, NULL
, NULL
);
576 irq_set_chip_data(irq
, NULL
);
579 static const struct irq_domain_ops gpiochip_domain_ops
= {
580 .map
= gpiochip_irq_map
,
581 .unmap
= gpiochip_irq_unmap
,
582 /* Virtually all GPIO irqchips are twocell:ed */
583 .xlate
= irq_domain_xlate_twocell
,
586 static int gpiochip_irq_reqres(struct irq_data
*d
)
588 struct gpio_chip
*chip
= irq_data_get_irq_chip_data(d
);
590 if (!try_module_get(chip
->owner
))
593 if (gpiochip_lock_as_irq(chip
, d
->hwirq
)) {
595 "unable to lock HW IRQ %lu for IRQ\n",
597 module_put(chip
->owner
);
603 static void gpiochip_irq_relres(struct irq_data
*d
)
605 struct gpio_chip
*chip
= irq_data_get_irq_chip_data(d
);
607 gpiochip_unlock_as_irq(chip
, d
->hwirq
);
608 module_put(chip
->owner
);
611 static int gpiochip_to_irq(struct gpio_chip
*chip
, unsigned offset
)
613 return irq_find_mapping(chip
->irqdomain
, offset
);
617 * gpiochip_irqchip_remove() - removes an irqchip added to a gpiochip
618 * @gpiochip: the gpiochip to remove the irqchip from
620 * This is called only from gpiochip_remove()
622 static void gpiochip_irqchip_remove(struct gpio_chip
*gpiochip
)
626 acpi_gpiochip_free_interrupts(gpiochip
);
628 if (gpiochip
->irq_parent
) {
629 irq_set_chained_handler(gpiochip
->irq_parent
, NULL
);
630 irq_set_handler_data(gpiochip
->irq_parent
, NULL
);
633 /* Remove all IRQ mappings and delete the domain */
634 if (gpiochip
->irqdomain
) {
635 for (offset
= 0; offset
< gpiochip
->ngpio
; offset
++)
637 irq_find_mapping(gpiochip
->irqdomain
, offset
));
638 irq_domain_remove(gpiochip
->irqdomain
);
641 if (gpiochip
->irqchip
) {
642 gpiochip
->irqchip
->irq_request_resources
= NULL
;
643 gpiochip
->irqchip
->irq_release_resources
= NULL
;
644 gpiochip
->irqchip
= NULL
;
649 * gpiochip_irqchip_add() - adds an irqchip to a gpiochip
650 * @gpiochip: the gpiochip to add the irqchip to
651 * @irqchip: the irqchip to add to the gpiochip
652 * @first_irq: if not dynamically assigned, the base (first) IRQ to
653 * allocate gpiochip irqs from
654 * @handler: the irq handler to use (often a predefined irq core function)
655 * @type: the default type for IRQs on this irqchip, pass IRQ_TYPE_NONE
656 * to have the core avoid setting up any default type in the hardware.
657 * @lock_key: lockdep class
659 * This function closely associates a certain irqchip with a certain
660 * gpiochip, providing an irq domain to translate the local IRQs to
661 * global irqs in the gpiolib core, and making sure that the gpiochip
662 * is passed as chip data to all related functions. Driver callbacks
663 * need to use container_of() to get their local state containers back
664 * from the gpiochip passed as chip data. An irqdomain will be stored
665 * in the gpiochip that shall be used by the driver to handle IRQ number
666 * translation. The gpiochip will need to be initialized and registered
667 * before calling this function.
669 * This function will handle two cell:ed simple IRQs and assumes all
670 * the pins on the gpiochip can generate a unique IRQ. Everything else
671 * need to be open coded.
673 int _gpiochip_irqchip_add(struct gpio_chip
*gpiochip
,
674 struct irq_chip
*irqchip
,
675 unsigned int first_irq
,
676 irq_flow_handler_t handler
,
678 struct lock_class_key
*lock_key
)
680 struct device_node
*of_node
;
682 unsigned irq_base
= 0;
684 if (!gpiochip
|| !irqchip
)
687 if (!gpiochip
->parent
) {
688 pr_err("missing gpiochip .dev parent pointer\n");
691 of_node
= gpiochip
->parent
->of_node
;
692 #ifdef CONFIG_OF_GPIO
694 * If the gpiochip has an assigned OF node this takes precedence
695 * FIXME: get rid of this and use gpiochip->dev->of_node everywhere
697 if (gpiochip
->of_node
)
698 of_node
= gpiochip
->of_node
;
700 gpiochip
->irqchip
= irqchip
;
701 gpiochip
->irq_handler
= handler
;
702 gpiochip
->irq_default_type
= type
;
703 gpiochip
->to_irq
= gpiochip_to_irq
;
704 gpiochip
->lock_key
= lock_key
;
705 gpiochip
->irqdomain
= irq_domain_add_simple(of_node
,
706 gpiochip
->ngpio
, first_irq
,
707 &gpiochip_domain_ops
, gpiochip
);
708 if (!gpiochip
->irqdomain
) {
709 gpiochip
->irqchip
= NULL
;
714 * It is possible for a driver to override this, but only if the
715 * alternative functions are both implemented.
717 if (!irqchip
->irq_request_resources
&&
718 !irqchip
->irq_release_resources
) {
719 irqchip
->irq_request_resources
= gpiochip_irq_reqres
;
720 irqchip
->irq_release_resources
= gpiochip_irq_relres
;
724 * Prepare the mapping since the irqchip shall be orthogonal to
725 * any gpiochip calls. If the first_irq was zero, this is
726 * necessary to allocate descriptors for all IRQs.
728 for (offset
= 0; offset
< gpiochip
->ngpio
; offset
++) {
729 irq_base
= irq_create_mapping(gpiochip
->irqdomain
, offset
);
732 * Store the base into the gpiochip to be used when
733 * unmapping the irqs.
735 gpiochip
->irq_base
= irq_base
;
738 acpi_gpiochip_request_interrupts(gpiochip
);
742 EXPORT_SYMBOL_GPL(_gpiochip_irqchip_add
);
744 #else /* CONFIG_GPIOLIB_IRQCHIP */
746 static void gpiochip_irqchip_remove(struct gpio_chip
*gpiochip
) {}
748 #endif /* CONFIG_GPIOLIB_IRQCHIP */
751 * gpiochip_generic_request() - request the gpio function for a pin
752 * @chip: the gpiochip owning the GPIO
753 * @offset: the offset of the GPIO to request for GPIO function
755 int gpiochip_generic_request(struct gpio_chip
*chip
, unsigned offset
)
757 return pinctrl_request_gpio(chip
->base
+ offset
);
759 EXPORT_SYMBOL_GPL(gpiochip_generic_request
);
762 * gpiochip_generic_free() - free the gpio function from a pin
763 * @chip: the gpiochip to request the gpio function for
764 * @offset: the offset of the GPIO to free from GPIO function
766 void gpiochip_generic_free(struct gpio_chip
*chip
, unsigned offset
)
768 pinctrl_free_gpio(chip
->base
+ offset
);
770 EXPORT_SYMBOL_GPL(gpiochip_generic_free
);
772 #ifdef CONFIG_PINCTRL
775 * gpiochip_add_pingroup_range() - add a range for GPIO <-> pin mapping
776 * @chip: the gpiochip to add the range for
777 * @pctldev: the pin controller to map to
778 * @gpio_offset: the start offset in the current gpio_chip number space
779 * @pin_group: name of the pin group inside the pin controller
781 int gpiochip_add_pingroup_range(struct gpio_chip
*chip
,
782 struct pinctrl_dev
*pctldev
,
783 unsigned int gpio_offset
, const char *pin_group
)
785 struct gpio_pin_range
*pin_range
;
788 pin_range
= kzalloc(sizeof(*pin_range
), GFP_KERNEL
);
790 chip_err(chip
, "failed to allocate pin ranges\n");
794 /* Use local offset as range ID */
795 pin_range
->range
.id
= gpio_offset
;
796 pin_range
->range
.gc
= chip
;
797 pin_range
->range
.name
= chip
->label
;
798 pin_range
->range
.base
= chip
->base
+ gpio_offset
;
799 pin_range
->pctldev
= pctldev
;
801 ret
= pinctrl_get_group_pins(pctldev
, pin_group
,
802 &pin_range
->range
.pins
,
803 &pin_range
->range
.npins
);
809 pinctrl_add_gpio_range(pctldev
, &pin_range
->range
);
811 chip_dbg(chip
, "created GPIO range %d->%d ==> %s PINGRP %s\n",
812 gpio_offset
, gpio_offset
+ pin_range
->range
.npins
- 1,
813 pinctrl_dev_get_devname(pctldev
), pin_group
);
815 list_add_tail(&pin_range
->node
, &chip
->pin_ranges
);
819 EXPORT_SYMBOL_GPL(gpiochip_add_pingroup_range
);
822 * gpiochip_add_pin_range() - add a range for GPIO <-> pin mapping
823 * @chip: the gpiochip to add the range for
824 * @pinctrl_name: the dev_name() of the pin controller to map to
825 * @gpio_offset: the start offset in the current gpio_chip number space
826 * @pin_offset: the start offset in the pin controller number space
827 * @npins: the number of pins from the offset of each pin space (GPIO and
828 * pin controller) to accumulate in this range
830 int gpiochip_add_pin_range(struct gpio_chip
*chip
, const char *pinctl_name
,
831 unsigned int gpio_offset
, unsigned int pin_offset
,
834 struct gpio_pin_range
*pin_range
;
837 pin_range
= kzalloc(sizeof(*pin_range
), GFP_KERNEL
);
839 chip_err(chip
, "failed to allocate pin ranges\n");
843 /* Use local offset as range ID */
844 pin_range
->range
.id
= gpio_offset
;
845 pin_range
->range
.gc
= chip
;
846 pin_range
->range
.name
= chip
->label
;
847 pin_range
->range
.base
= chip
->base
+ gpio_offset
;
848 pin_range
->range
.pin_base
= pin_offset
;
849 pin_range
->range
.npins
= npins
;
850 pin_range
->pctldev
= pinctrl_find_and_add_gpio_range(pinctl_name
,
852 if (IS_ERR(pin_range
->pctldev
)) {
853 ret
= PTR_ERR(pin_range
->pctldev
);
854 chip_err(chip
, "could not create pin range\n");
858 chip_dbg(chip
, "created GPIO range %d->%d ==> %s PIN %d->%d\n",
859 gpio_offset
, gpio_offset
+ npins
- 1,
861 pin_offset
, pin_offset
+ npins
- 1);
863 list_add_tail(&pin_range
->node
, &chip
->pin_ranges
);
867 EXPORT_SYMBOL_GPL(gpiochip_add_pin_range
);
870 * gpiochip_remove_pin_ranges() - remove all the GPIO <-> pin mappings
871 * @chip: the chip to remove all the mappings for
873 void gpiochip_remove_pin_ranges(struct gpio_chip
*chip
)
875 struct gpio_pin_range
*pin_range
, *tmp
;
877 list_for_each_entry_safe(pin_range
, tmp
, &chip
->pin_ranges
, node
) {
878 list_del(&pin_range
->node
);
879 pinctrl_remove_gpio_range(pin_range
->pctldev
,
884 EXPORT_SYMBOL_GPL(gpiochip_remove_pin_ranges
);
886 #endif /* CONFIG_PINCTRL */
888 /* These "optional" allocation calls help prevent drivers from stomping
889 * on each other, and help provide better diagnostics in debugfs.
890 * They're called even less than the "set direction" calls.
892 static int __gpiod_request(struct gpio_desc
*desc
, const char *label
)
894 struct gpio_chip
*chip
= desc
->chip
;
898 spin_lock_irqsave(&gpio_lock
, flags
);
900 /* NOTE: gpio_request() can be called in early boot,
901 * before IRQs are enabled, for non-sleeping (SOC) GPIOs.
904 if (test_and_set_bit(FLAG_REQUESTED
, &desc
->flags
) == 0) {
905 desc_set_label(desc
, label
? : "?");
913 /* chip->request may sleep */
914 spin_unlock_irqrestore(&gpio_lock
, flags
);
915 status
= chip
->request(chip
, gpio_chip_hwgpio(desc
));
916 spin_lock_irqsave(&gpio_lock
, flags
);
919 desc_set_label(desc
, NULL
);
920 clear_bit(FLAG_REQUESTED
, &desc
->flags
);
924 if (chip
->get_direction
) {
925 /* chip->get_direction may sleep */
926 spin_unlock_irqrestore(&gpio_lock
, flags
);
927 gpiod_get_direction(desc
);
928 spin_lock_irqsave(&gpio_lock
, flags
);
932 /* Clear flags that might have been set by the caller before
933 * requesting the GPIO.
935 clear_bit(FLAG_ACTIVE_LOW
, &desc
->flags
);
936 clear_bit(FLAG_OPEN_DRAIN
, &desc
->flags
);
937 clear_bit(FLAG_OPEN_SOURCE
, &desc
->flags
);
939 spin_unlock_irqrestore(&gpio_lock
, flags
);
943 int gpiod_request(struct gpio_desc
*desc
, const char *label
)
945 int status
= -EPROBE_DEFER
;
946 struct gpio_chip
*chip
;
949 pr_warn("%s: invalid GPIO\n", __func__
);
957 if (try_module_get(chip
->owner
)) {
958 status
= __gpiod_request(desc
, label
);
960 module_put(chip
->owner
);
965 gpiod_dbg(desc
, "%s: status %d\n", __func__
, status
);
970 static bool __gpiod_free(struct gpio_desc
*desc
)
974 struct gpio_chip
*chip
;
978 gpiod_unexport(desc
);
980 spin_lock_irqsave(&gpio_lock
, flags
);
983 if (chip
&& test_bit(FLAG_REQUESTED
, &desc
->flags
)) {
985 spin_unlock_irqrestore(&gpio_lock
, flags
);
986 might_sleep_if(chip
->can_sleep
);
987 chip
->free(chip
, gpio_chip_hwgpio(desc
));
988 spin_lock_irqsave(&gpio_lock
, flags
);
990 desc_set_label(desc
, NULL
);
991 clear_bit(FLAG_ACTIVE_LOW
, &desc
->flags
);
992 clear_bit(FLAG_REQUESTED
, &desc
->flags
);
993 clear_bit(FLAG_OPEN_DRAIN
, &desc
->flags
);
994 clear_bit(FLAG_OPEN_SOURCE
, &desc
->flags
);
995 clear_bit(FLAG_IS_HOGGED
, &desc
->flags
);
999 spin_unlock_irqrestore(&gpio_lock
, flags
);
1003 void gpiod_free(struct gpio_desc
*desc
)
1005 if (desc
&& __gpiod_free(desc
))
1006 module_put(desc
->chip
->owner
);
1008 WARN_ON(extra_checks
);
1012 * gpiochip_is_requested - return string iff signal was requested
1013 * @chip: controller managing the signal
1014 * @offset: of signal within controller's 0..(ngpio - 1) range
1016 * Returns NULL if the GPIO is not currently requested, else a string.
1017 * The string returned is the label passed to gpio_request(); if none has been
1018 * passed it is a meaningless, non-NULL constant.
1020 * This function is for use by GPIO controller drivers. The label can
1021 * help with diagnostics, and knowing that the signal is used as a GPIO
1022 * can help avoid accidentally multiplexing it to another controller.
1024 const char *gpiochip_is_requested(struct gpio_chip
*chip
, unsigned offset
)
1026 struct gpio_desc
*desc
;
1028 if (offset
>= chip
->ngpio
)
1031 desc
= &chip
->desc
[offset
];
1033 if (test_bit(FLAG_REQUESTED
, &desc
->flags
) == 0)
1037 EXPORT_SYMBOL_GPL(gpiochip_is_requested
);
1040 * gpiochip_request_own_desc - Allow GPIO chip to request its own descriptor
1041 * @desc: GPIO descriptor to request
1042 * @label: label for the GPIO
1044 * Function allows GPIO chip drivers to request and use their own GPIO
1045 * descriptors via gpiolib API. Difference to gpiod_request() is that this
1046 * function will not increase reference count of the GPIO chip module. This
1047 * allows the GPIO chip module to be unloaded as needed (we assume that the
1048 * GPIO chip driver handles freeing the GPIOs it has requested).
1050 struct gpio_desc
*gpiochip_request_own_desc(struct gpio_chip
*chip
, u16 hwnum
,
1053 struct gpio_desc
*desc
= gpiochip_get_desc(chip
, hwnum
);
1057 chip_err(chip
, "failed to get GPIO descriptor\n");
1061 err
= __gpiod_request(desc
, label
);
1063 return ERR_PTR(err
);
1067 EXPORT_SYMBOL_GPL(gpiochip_request_own_desc
);
1070 * gpiochip_free_own_desc - Free GPIO requested by the chip driver
1071 * @desc: GPIO descriptor to free
1073 * Function frees the given GPIO requested previously with
1074 * gpiochip_request_own_desc().
1076 void gpiochip_free_own_desc(struct gpio_desc
*desc
)
1081 EXPORT_SYMBOL_GPL(gpiochip_free_own_desc
);
1083 /* Drivers MUST set GPIO direction before making get/set calls. In
1084 * some cases this is done in early boot, before IRQs are enabled.
1086 * As a rule these aren't called more than once (except for drivers
1087 * using the open-drain emulation idiom) so these are natural places
1088 * to accumulate extra debugging checks. Note that we can't (yet)
1089 * rely on gpio_request() having been called beforehand.
1093 * gpiod_direction_input - set the GPIO direction to input
1094 * @desc: GPIO to set to input
1096 * Set the direction of the passed GPIO to input, such as gpiod_get_value() can
1097 * be called safely on it.
1099 * Return 0 in case of success, else an error code.
1101 int gpiod_direction_input(struct gpio_desc
*desc
)
1103 struct gpio_chip
*chip
;
1104 int status
= -EINVAL
;
1106 if (!desc
|| !desc
->chip
) {
1107 pr_warn("%s: invalid GPIO\n", __func__
);
1112 if (!chip
->get
|| !chip
->direction_input
) {
1114 "%s: missing get() or direction_input() operations\n",
1119 status
= chip
->direction_input(chip
, gpio_chip_hwgpio(desc
));
1121 clear_bit(FLAG_IS_OUT
, &desc
->flags
);
1123 trace_gpio_direction(desc_to_gpio(desc
), 1, status
);
1127 EXPORT_SYMBOL_GPL(gpiod_direction_input
);
1129 static int _gpiod_direction_output_raw(struct gpio_desc
*desc
, int value
)
1131 struct gpio_chip
*chip
;
1132 int status
= -EINVAL
;
1134 /* GPIOs used for IRQs shall not be set as output */
1135 if (test_bit(FLAG_USED_AS_IRQ
, &desc
->flags
)) {
1137 "%s: tried to set a GPIO tied to an IRQ as output\n",
1142 /* Open drain pin should not be driven to 1 */
1143 if (value
&& test_bit(FLAG_OPEN_DRAIN
, &desc
->flags
))
1144 return gpiod_direction_input(desc
);
1146 /* Open source pin should not be driven to 0 */
1147 if (!value
&& test_bit(FLAG_OPEN_SOURCE
, &desc
->flags
))
1148 return gpiod_direction_input(desc
);
1151 if (!chip
->set
|| !chip
->direction_output
) {
1153 "%s: missing set() or direction_output() operations\n",
1158 status
= chip
->direction_output(chip
, gpio_chip_hwgpio(desc
), value
);
1160 set_bit(FLAG_IS_OUT
, &desc
->flags
);
1161 trace_gpio_value(desc_to_gpio(desc
), 0, value
);
1162 trace_gpio_direction(desc_to_gpio(desc
), 0, status
);
1167 * gpiod_direction_output_raw - set the GPIO direction to output
1168 * @desc: GPIO to set to output
1169 * @value: initial output value of the GPIO
1171 * Set the direction of the passed GPIO to output, such as gpiod_set_value() can
1172 * be called safely on it. The initial value of the output must be specified
1173 * as raw value on the physical line without regard for the ACTIVE_LOW status.
1175 * Return 0 in case of success, else an error code.
1177 int gpiod_direction_output_raw(struct gpio_desc
*desc
, int value
)
1179 if (!desc
|| !desc
->chip
) {
1180 pr_warn("%s: invalid GPIO\n", __func__
);
1183 return _gpiod_direction_output_raw(desc
, value
);
1185 EXPORT_SYMBOL_GPL(gpiod_direction_output_raw
);
1188 * gpiod_direction_output - set the GPIO direction to output
1189 * @desc: GPIO to set to output
1190 * @value: initial output value of the GPIO
1192 * Set the direction of the passed GPIO to output, such as gpiod_set_value() can
1193 * be called safely on it. The initial value of the output must be specified
1194 * as the logical value of the GPIO, i.e. taking its ACTIVE_LOW status into
1197 * Return 0 in case of success, else an error code.
1199 int gpiod_direction_output(struct gpio_desc
*desc
, int value
)
1201 if (!desc
|| !desc
->chip
) {
1202 pr_warn("%s: invalid GPIO\n", __func__
);
1205 if (test_bit(FLAG_ACTIVE_LOW
, &desc
->flags
))
1207 return _gpiod_direction_output_raw(desc
, value
);
1209 EXPORT_SYMBOL_GPL(gpiod_direction_output
);
1212 * gpiod_set_debounce - sets @debounce time for a @gpio
1213 * @gpio: the gpio to set debounce time
1214 * @debounce: debounce time is microseconds
1216 * returns -ENOTSUPP if the controller does not support setting
1219 int gpiod_set_debounce(struct gpio_desc
*desc
, unsigned debounce
)
1221 struct gpio_chip
*chip
;
1223 if (!desc
|| !desc
->chip
) {
1224 pr_warn("%s: invalid GPIO\n", __func__
);
1229 if (!chip
->set
|| !chip
->set_debounce
) {
1231 "%s: missing set() or set_debounce() operations\n",
1236 return chip
->set_debounce(chip
, gpio_chip_hwgpio(desc
), debounce
);
1238 EXPORT_SYMBOL_GPL(gpiod_set_debounce
);
1241 * gpiod_is_active_low - test whether a GPIO is active-low or not
1242 * @desc: the gpio descriptor to test
1244 * Returns 1 if the GPIO is active-low, 0 otherwise.
1246 int gpiod_is_active_low(const struct gpio_desc
*desc
)
1248 return test_bit(FLAG_ACTIVE_LOW
, &desc
->flags
);
1250 EXPORT_SYMBOL_GPL(gpiod_is_active_low
);
1252 /* I/O calls are only valid after configuration completed; the relevant
1253 * "is this a valid GPIO" error checks should already have been done.
1255 * "Get" operations are often inlinable as reading a pin value register,
1256 * and masking the relevant bit in that register.
1258 * When "set" operations are inlinable, they involve writing that mask to
1259 * one register to set a low value, or a different register to set it high.
1260 * Otherwise locking is needed, so there may be little value to inlining.
1262 *------------------------------------------------------------------------
1264 * IMPORTANT!!! The hot paths -- get/set value -- assume that callers
1265 * have requested the GPIO. That can include implicit requesting by
1266 * a direction setting call. Marking a gpio as requested locks its chip
1267 * in memory, guaranteeing that these table lookups need no more locking
1268 * and that gpiochip_remove() will fail.
1270 * REVISIT when debugging, consider adding some instrumentation to ensure
1271 * that the GPIO was actually requested.
1274 static int _gpiod_get_raw_value(const struct gpio_desc
*desc
)
1276 struct gpio_chip
*chip
;
1281 offset
= gpio_chip_hwgpio(desc
);
1282 value
= chip
->get
? chip
->get(chip
, offset
) : -EIO
;
1283 value
= value
< 0 ? value
: !!value
;
1284 trace_gpio_value(desc_to_gpio(desc
), 1, value
);
1289 * gpiod_get_raw_value() - return a gpio's raw value
1290 * @desc: gpio whose value will be returned
1292 * Return the GPIO's raw value, i.e. the value of the physical line disregarding
1293 * its ACTIVE_LOW status, or negative errno on failure.
1295 * This function should be called from contexts where we cannot sleep, and will
1296 * complain if the GPIO chip functions potentially sleep.
1298 int gpiod_get_raw_value(const struct gpio_desc
*desc
)
1302 /* Should be using gpio_get_value_cansleep() */
1303 WARN_ON(desc
->chip
->can_sleep
);
1304 return _gpiod_get_raw_value(desc
);
1306 EXPORT_SYMBOL_GPL(gpiod_get_raw_value
);
1309 * gpiod_get_value() - return a gpio's value
1310 * @desc: gpio whose value will be returned
1312 * Return the GPIO's logical value, i.e. taking the ACTIVE_LOW status into
1313 * account, or negative errno on failure.
1315 * This function should be called from contexts where we cannot sleep, and will
1316 * complain if the GPIO chip functions potentially sleep.
1318 int gpiod_get_value(const struct gpio_desc
*desc
)
1323 /* Should be using gpio_get_value_cansleep() */
1324 WARN_ON(desc
->chip
->can_sleep
);
1326 value
= _gpiod_get_raw_value(desc
);
1330 if (test_bit(FLAG_ACTIVE_LOW
, &desc
->flags
))
1335 EXPORT_SYMBOL_GPL(gpiod_get_value
);
1338 * _gpio_set_open_drain_value() - Set the open drain gpio's value.
1339 * @desc: gpio descriptor whose state need to be set.
1340 * @value: Non-zero for setting it HIGH otherwise it will set to LOW.
1342 static void _gpio_set_open_drain_value(struct gpio_desc
*desc
, bool value
)
1345 struct gpio_chip
*chip
= desc
->chip
;
1346 int offset
= gpio_chip_hwgpio(desc
);
1349 err
= chip
->direction_input(chip
, offset
);
1351 clear_bit(FLAG_IS_OUT
, &desc
->flags
);
1353 err
= chip
->direction_output(chip
, offset
, 0);
1355 set_bit(FLAG_IS_OUT
, &desc
->flags
);
1357 trace_gpio_direction(desc_to_gpio(desc
), value
, err
);
1360 "%s: Error in set_value for open drain err %d\n",
1365 * _gpio_set_open_source_value() - Set the open source gpio's value.
1366 * @desc: gpio descriptor whose state need to be set.
1367 * @value: Non-zero for setting it HIGH otherwise it will set to LOW.
1369 static void _gpio_set_open_source_value(struct gpio_desc
*desc
, bool value
)
1372 struct gpio_chip
*chip
= desc
->chip
;
1373 int offset
= gpio_chip_hwgpio(desc
);
1376 err
= chip
->direction_output(chip
, offset
, 1);
1378 set_bit(FLAG_IS_OUT
, &desc
->flags
);
1380 err
= chip
->direction_input(chip
, offset
);
1382 clear_bit(FLAG_IS_OUT
, &desc
->flags
);
1384 trace_gpio_direction(desc_to_gpio(desc
), !value
, err
);
1387 "%s: Error in set_value for open source err %d\n",
1391 static void _gpiod_set_raw_value(struct gpio_desc
*desc
, bool value
)
1393 struct gpio_chip
*chip
;
1396 trace_gpio_value(desc_to_gpio(desc
), 0, value
);
1397 if (test_bit(FLAG_OPEN_DRAIN
, &desc
->flags
))
1398 _gpio_set_open_drain_value(desc
, value
);
1399 else if (test_bit(FLAG_OPEN_SOURCE
, &desc
->flags
))
1400 _gpio_set_open_source_value(desc
, value
);
1402 chip
->set(chip
, gpio_chip_hwgpio(desc
), value
);
1406 * set multiple outputs on the same chip;
1407 * use the chip's set_multiple function if available;
1408 * otherwise set the outputs sequentially;
1409 * @mask: bit mask array; one bit per output; BITS_PER_LONG bits per word
1410 * defines which outputs are to be changed
1411 * @bits: bit value array; one bit per output; BITS_PER_LONG bits per word
1412 * defines the values the outputs specified by mask are to be set to
1414 static void gpio_chip_set_multiple(struct gpio_chip
*chip
,
1415 unsigned long *mask
, unsigned long *bits
)
1417 if (chip
->set_multiple
) {
1418 chip
->set_multiple(chip
, mask
, bits
);
1421 for (i
= 0; i
< chip
->ngpio
; i
++) {
1422 if (mask
[BIT_WORD(i
)] == 0) {
1423 /* no more set bits in this mask word;
1424 * skip ahead to the next word */
1425 i
= (BIT_WORD(i
) + 1) * BITS_PER_LONG
- 1;
1428 /* set outputs if the corresponding mask bit is set */
1429 if (__test_and_clear_bit(i
, mask
))
1430 chip
->set(chip
, i
, test_bit(i
, bits
));
1435 static void gpiod_set_array_value_priv(bool raw
, bool can_sleep
,
1436 unsigned int array_size
,
1437 struct gpio_desc
**desc_array
,
1442 while (i
< array_size
) {
1443 struct gpio_chip
*chip
= desc_array
[i
]->chip
;
1444 unsigned long mask
[BITS_TO_LONGS(chip
->ngpio
)];
1445 unsigned long bits
[BITS_TO_LONGS(chip
->ngpio
)];
1449 WARN_ON(chip
->can_sleep
);
1451 memset(mask
, 0, sizeof(mask
));
1453 struct gpio_desc
*desc
= desc_array
[i
];
1454 int hwgpio
= gpio_chip_hwgpio(desc
);
1455 int value
= value_array
[i
];
1457 if (!raw
&& test_bit(FLAG_ACTIVE_LOW
, &desc
->flags
))
1459 trace_gpio_value(desc_to_gpio(desc
), 0, value
);
1461 * collect all normal outputs belonging to the same chip
1462 * open drain and open source outputs are set individually
1464 if (test_bit(FLAG_OPEN_DRAIN
, &desc
->flags
)) {
1465 _gpio_set_open_drain_value(desc
, value
);
1466 } else if (test_bit(FLAG_OPEN_SOURCE
, &desc
->flags
)) {
1467 _gpio_set_open_source_value(desc
, value
);
1469 __set_bit(hwgpio
, mask
);
1471 __set_bit(hwgpio
, bits
);
1473 __clear_bit(hwgpio
, bits
);
1477 } while ((i
< array_size
) && (desc_array
[i
]->chip
== chip
));
1478 /* push collected bits to outputs */
1480 gpio_chip_set_multiple(chip
, mask
, bits
);
1485 * gpiod_set_raw_value() - assign a gpio's raw value
1486 * @desc: gpio whose value will be assigned
1487 * @value: value to assign
1489 * Set the raw value of the GPIO, i.e. the value of its physical line without
1490 * regard for its ACTIVE_LOW status.
1492 * This function should be called from contexts where we cannot sleep, and will
1493 * complain if the GPIO chip functions potentially sleep.
1495 void gpiod_set_raw_value(struct gpio_desc
*desc
, int value
)
1499 /* Should be using gpio_set_value_cansleep() */
1500 WARN_ON(desc
->chip
->can_sleep
);
1501 _gpiod_set_raw_value(desc
, value
);
1503 EXPORT_SYMBOL_GPL(gpiod_set_raw_value
);
1506 * gpiod_set_value() - assign a gpio's value
1507 * @desc: gpio whose value will be assigned
1508 * @value: value to assign
1510 * Set the logical value of the GPIO, i.e. taking its ACTIVE_LOW status into
1513 * This function should be called from contexts where we cannot sleep, and will
1514 * complain if the GPIO chip functions potentially sleep.
1516 void gpiod_set_value(struct gpio_desc
*desc
, int value
)
1520 /* Should be using gpio_set_value_cansleep() */
1521 WARN_ON(desc
->chip
->can_sleep
);
1522 if (test_bit(FLAG_ACTIVE_LOW
, &desc
->flags
))
1524 _gpiod_set_raw_value(desc
, value
);
1526 EXPORT_SYMBOL_GPL(gpiod_set_value
);
1529 * gpiod_set_raw_array_value() - assign values to an array of GPIOs
1530 * @array_size: number of elements in the descriptor / value arrays
1531 * @desc_array: array of GPIO descriptors whose values will be assigned
1532 * @value_array: array of values to assign
1534 * Set the raw values of the GPIOs, i.e. the values of the physical lines
1535 * without regard for their ACTIVE_LOW status.
1537 * This function should be called from contexts where we cannot sleep, and will
1538 * complain if the GPIO chip functions potentially sleep.
1540 void gpiod_set_raw_array_value(unsigned int array_size
,
1541 struct gpio_desc
**desc_array
, int *value_array
)
1545 gpiod_set_array_value_priv(true, false, array_size
, desc_array
,
1548 EXPORT_SYMBOL_GPL(gpiod_set_raw_array_value
);
1551 * gpiod_set_array_value() - assign values to an array of GPIOs
1552 * @array_size: number of elements in the descriptor / value arrays
1553 * @desc_array: array of GPIO descriptors whose values will be assigned
1554 * @value_array: array of values to assign
1556 * Set the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status
1559 * This function should be called from contexts where we cannot sleep, and will
1560 * complain if the GPIO chip functions potentially sleep.
1562 void gpiod_set_array_value(unsigned int array_size
,
1563 struct gpio_desc
**desc_array
, int *value_array
)
1567 gpiod_set_array_value_priv(false, false, array_size
, desc_array
,
1570 EXPORT_SYMBOL_GPL(gpiod_set_array_value
);
1573 * gpiod_cansleep() - report whether gpio value access may sleep
1574 * @desc: gpio to check
1577 int gpiod_cansleep(const struct gpio_desc
*desc
)
1581 return desc
->chip
->can_sleep
;
1583 EXPORT_SYMBOL_GPL(gpiod_cansleep
);
1586 * gpiod_to_irq() - return the IRQ corresponding to a GPIO
1587 * @desc: gpio whose IRQ will be returned (already requested)
1589 * Return the IRQ corresponding to the passed GPIO, or an error code in case of
1592 int gpiod_to_irq(const struct gpio_desc
*desc
)
1594 struct gpio_chip
*chip
;
1600 offset
= gpio_chip_hwgpio(desc
);
1601 return chip
->to_irq
? chip
->to_irq(chip
, offset
) : -ENXIO
;
1603 EXPORT_SYMBOL_GPL(gpiod_to_irq
);
1606 * gpiochip_lock_as_irq() - lock a GPIO to be used as IRQ
1607 * @chip: the chip the GPIO to lock belongs to
1608 * @offset: the offset of the GPIO to lock as IRQ
1610 * This is used directly by GPIO drivers that want to lock down
1611 * a certain GPIO line to be used for IRQs.
1613 int gpiochip_lock_as_irq(struct gpio_chip
*chip
, unsigned int offset
)
1615 if (offset
>= chip
->ngpio
)
1618 if (test_bit(FLAG_IS_OUT
, &chip
->desc
[offset
].flags
)) {
1620 "%s: tried to flag a GPIO set as output for IRQ\n",
1625 set_bit(FLAG_USED_AS_IRQ
, &chip
->desc
[offset
].flags
);
1628 EXPORT_SYMBOL_GPL(gpiochip_lock_as_irq
);
1631 * gpiochip_unlock_as_irq() - unlock a GPIO used as IRQ
1632 * @chip: the chip the GPIO to lock belongs to
1633 * @offset: the offset of the GPIO to lock as IRQ
1635 * This is used directly by GPIO drivers that want to indicate
1636 * that a certain GPIO is no longer used exclusively for IRQ.
1638 void gpiochip_unlock_as_irq(struct gpio_chip
*chip
, unsigned int offset
)
1640 if (offset
>= chip
->ngpio
)
1643 clear_bit(FLAG_USED_AS_IRQ
, &chip
->desc
[offset
].flags
);
1645 EXPORT_SYMBOL_GPL(gpiochip_unlock_as_irq
);
1648 * gpiod_get_raw_value_cansleep() - return a gpio's raw value
1649 * @desc: gpio whose value will be returned
1651 * Return the GPIO's raw value, i.e. the value of the physical line disregarding
1652 * its ACTIVE_LOW status, or negative errno on failure.
1654 * This function is to be called from contexts that can sleep.
1656 int gpiod_get_raw_value_cansleep(const struct gpio_desc
*desc
)
1658 might_sleep_if(extra_checks
);
1661 return _gpiod_get_raw_value(desc
);
1663 EXPORT_SYMBOL_GPL(gpiod_get_raw_value_cansleep
);
1666 * gpiod_get_value_cansleep() - return a gpio's value
1667 * @desc: gpio whose value will be returned
1669 * Return the GPIO's logical value, i.e. taking the ACTIVE_LOW status into
1670 * account, or negative errno on failure.
1672 * This function is to be called from contexts that can sleep.
1674 int gpiod_get_value_cansleep(const struct gpio_desc
*desc
)
1678 might_sleep_if(extra_checks
);
1682 value
= _gpiod_get_raw_value(desc
);
1686 if (test_bit(FLAG_ACTIVE_LOW
, &desc
->flags
))
1691 EXPORT_SYMBOL_GPL(gpiod_get_value_cansleep
);
1694 * gpiod_set_raw_value_cansleep() - assign a gpio's raw value
1695 * @desc: gpio whose value will be assigned
1696 * @value: value to assign
1698 * Set the raw value of the GPIO, i.e. the value of its physical line without
1699 * regard for its ACTIVE_LOW status.
1701 * This function is to be called from contexts that can sleep.
1703 void gpiod_set_raw_value_cansleep(struct gpio_desc
*desc
, int value
)
1705 might_sleep_if(extra_checks
);
1708 _gpiod_set_raw_value(desc
, value
);
1710 EXPORT_SYMBOL_GPL(gpiod_set_raw_value_cansleep
);
1713 * gpiod_set_value_cansleep() - assign a gpio's value
1714 * @desc: gpio whose value will be assigned
1715 * @value: value to assign
1717 * Set the logical value of the GPIO, i.e. taking its ACTIVE_LOW status into
1720 * This function is to be called from contexts that can sleep.
1722 void gpiod_set_value_cansleep(struct gpio_desc
*desc
, int value
)
1724 might_sleep_if(extra_checks
);
1728 if (test_bit(FLAG_ACTIVE_LOW
, &desc
->flags
))
1730 _gpiod_set_raw_value(desc
, value
);
1732 EXPORT_SYMBOL_GPL(gpiod_set_value_cansleep
);
1735 * gpiod_set_raw_array_value_cansleep() - assign values to an array of GPIOs
1736 * @array_size: number of elements in the descriptor / value arrays
1737 * @desc_array: array of GPIO descriptors whose values will be assigned
1738 * @value_array: array of values to assign
1740 * Set the raw values of the GPIOs, i.e. the values of the physical lines
1741 * without regard for their ACTIVE_LOW status.
1743 * This function is to be called from contexts that can sleep.
1745 void gpiod_set_raw_array_value_cansleep(unsigned int array_size
,
1746 struct gpio_desc
**desc_array
,
1749 might_sleep_if(extra_checks
);
1752 gpiod_set_array_value_priv(true, true, array_size
, desc_array
,
1755 EXPORT_SYMBOL_GPL(gpiod_set_raw_array_value_cansleep
);
1758 * gpiod_set_array_value_cansleep() - assign values to an array of GPIOs
1759 * @array_size: number of elements in the descriptor / value arrays
1760 * @desc_array: array of GPIO descriptors whose values will be assigned
1761 * @value_array: array of values to assign
1763 * Set the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status
1766 * This function is to be called from contexts that can sleep.
1768 void gpiod_set_array_value_cansleep(unsigned int array_size
,
1769 struct gpio_desc
**desc_array
,
1772 might_sleep_if(extra_checks
);
1775 gpiod_set_array_value_priv(false, true, array_size
, desc_array
,
1778 EXPORT_SYMBOL_GPL(gpiod_set_array_value_cansleep
);
1781 * gpiod_add_lookup_table() - register GPIO device consumers
1782 * @table: table of consumers to register
1784 void gpiod_add_lookup_table(struct gpiod_lookup_table
*table
)
1786 mutex_lock(&gpio_lookup_lock
);
1788 list_add_tail(&table
->list
, &gpio_lookup_list
);
1790 mutex_unlock(&gpio_lookup_lock
);
1794 * gpiod_remove_lookup_table() - unregister GPIO device consumers
1795 * @table: table of consumers to unregister
1797 void gpiod_remove_lookup_table(struct gpiod_lookup_table
*table
)
1799 mutex_lock(&gpio_lookup_lock
);
1801 list_del(&table
->list
);
1803 mutex_unlock(&gpio_lookup_lock
);
1806 static struct gpio_desc
*of_find_gpio(struct device
*dev
, const char *con_id
,
1808 enum gpio_lookup_flags
*flags
)
1810 char prop_name
[32]; /* 32 is max size of property name */
1811 enum of_gpio_flags of_flags
;
1812 struct gpio_desc
*desc
;
1815 for (i
= 0; i
< ARRAY_SIZE(gpio_suffixes
); i
++) {
1817 snprintf(prop_name
, sizeof(prop_name
), "%s-%s", con_id
,
1820 snprintf(prop_name
, sizeof(prop_name
), "%s",
1823 desc
= of_get_named_gpiod_flags(dev
->of_node
, prop_name
, idx
,
1825 if (!IS_ERR(desc
) || (PTR_ERR(desc
) == -EPROBE_DEFER
))
1832 if (of_flags
& OF_GPIO_ACTIVE_LOW
)
1833 *flags
|= GPIO_ACTIVE_LOW
;
1835 if (of_flags
& OF_GPIO_SINGLE_ENDED
) {
1836 if (of_flags
& OF_GPIO_ACTIVE_LOW
)
1837 *flags
|= GPIO_OPEN_DRAIN
;
1839 *flags
|= GPIO_OPEN_SOURCE
;
1845 static struct gpio_desc
*acpi_find_gpio(struct device
*dev
, const char *con_id
,
1847 enum gpio_lookup_flags
*flags
)
1849 struct acpi_device
*adev
= ACPI_COMPANION(dev
);
1850 struct acpi_gpio_info info
;
1851 struct gpio_desc
*desc
;
1855 /* Try first from _DSD */
1856 for (i
= 0; i
< ARRAY_SIZE(gpio_suffixes
); i
++) {
1857 if (con_id
&& strcmp(con_id
, "gpios")) {
1858 snprintf(propname
, sizeof(propname
), "%s-%s",
1859 con_id
, gpio_suffixes
[i
]);
1861 snprintf(propname
, sizeof(propname
), "%s",
1865 desc
= acpi_get_gpiod_by_index(adev
, propname
, idx
, &info
);
1866 if (!IS_ERR(desc
) || (PTR_ERR(desc
) == -EPROBE_DEFER
))
1870 /* Then from plain _CRS GPIOs */
1872 desc
= acpi_get_gpiod_by_index(adev
, NULL
, idx
, &info
);
1877 if (info
.active_low
)
1878 *flags
|= GPIO_ACTIVE_LOW
;
1883 static struct gpiod_lookup_table
*gpiod_find_lookup_table(struct device
*dev
)
1885 const char *dev_id
= dev
? dev_name(dev
) : NULL
;
1886 struct gpiod_lookup_table
*table
;
1888 mutex_lock(&gpio_lookup_lock
);
1890 list_for_each_entry(table
, &gpio_lookup_list
, list
) {
1891 if (table
->dev_id
&& dev_id
) {
1893 * Valid strings on both ends, must be identical to have
1896 if (!strcmp(table
->dev_id
, dev_id
))
1900 * One of the pointers is NULL, so both must be to have
1903 if (dev_id
== table
->dev_id
)
1910 mutex_unlock(&gpio_lookup_lock
);
1914 static struct gpio_desc
*gpiod_find(struct device
*dev
, const char *con_id
,
1916 enum gpio_lookup_flags
*flags
)
1918 struct gpio_desc
*desc
= ERR_PTR(-ENOENT
);
1919 struct gpiod_lookup_table
*table
;
1920 struct gpiod_lookup
*p
;
1922 table
= gpiod_find_lookup_table(dev
);
1926 for (p
= &table
->table
[0]; p
->chip_label
; p
++) {
1927 struct gpio_chip
*chip
;
1929 /* idx must always match exactly */
1933 /* If the lookup entry has a con_id, require exact match */
1934 if (p
->con_id
&& (!con_id
|| strcmp(p
->con_id
, con_id
)))
1937 chip
= find_chip_by_name(p
->chip_label
);
1940 dev_err(dev
, "cannot find GPIO chip %s\n",
1942 return ERR_PTR(-ENODEV
);
1945 if (chip
->ngpio
<= p
->chip_hwnum
) {
1947 "requested GPIO %d is out of range [0..%d] for chip %s\n",
1948 idx
, chip
->ngpio
, chip
->label
);
1949 return ERR_PTR(-EINVAL
);
1952 desc
= gpiochip_get_desc(chip
, p
->chip_hwnum
);
1961 static int dt_gpio_count(struct device
*dev
, const char *con_id
)
1967 for (i
= 0; i
< ARRAY_SIZE(gpio_suffixes
); i
++) {
1969 snprintf(propname
, sizeof(propname
), "%s-%s",
1970 con_id
, gpio_suffixes
[i
]);
1972 snprintf(propname
, sizeof(propname
), "%s",
1975 ret
= of_gpio_named_count(dev
->of_node
, propname
);
1982 static int platform_gpio_count(struct device
*dev
, const char *con_id
)
1984 struct gpiod_lookup_table
*table
;
1985 struct gpiod_lookup
*p
;
1986 unsigned int count
= 0;
1988 table
= gpiod_find_lookup_table(dev
);
1992 for (p
= &table
->table
[0]; p
->chip_label
; p
++) {
1993 if ((con_id
&& p
->con_id
&& !strcmp(con_id
, p
->con_id
)) ||
1994 (!con_id
&& !p
->con_id
))
2004 * gpiod_count - return the number of GPIOs associated with a device / function
2005 * or -ENOENT if no GPIO has been assigned to the requested function
2006 * @dev: GPIO consumer, can be NULL for system-global GPIOs
2007 * @con_id: function within the GPIO consumer
2009 int gpiod_count(struct device
*dev
, const char *con_id
)
2011 int count
= -ENOENT
;
2013 if (IS_ENABLED(CONFIG_OF
) && dev
&& dev
->of_node
)
2014 count
= dt_gpio_count(dev
, con_id
);
2015 else if (IS_ENABLED(CONFIG_ACPI
) && dev
&& ACPI_HANDLE(dev
))
2016 count
= acpi_gpio_count(dev
, con_id
);
2019 count
= platform_gpio_count(dev
, con_id
);
2023 EXPORT_SYMBOL_GPL(gpiod_count
);
2026 * gpiod_get - obtain a GPIO for a given GPIO function
2027 * @dev: GPIO consumer, can be NULL for system-global GPIOs
2028 * @con_id: function within the GPIO consumer
2029 * @flags: optional GPIO initialization flags
2031 * Return the GPIO descriptor corresponding to the function con_id of device
2032 * dev, -ENOENT if no GPIO has been assigned to the requested function, or
2033 * another IS_ERR() code if an error occurred while trying to acquire the GPIO.
2035 struct gpio_desc
*__must_check
gpiod_get(struct device
*dev
, const char *con_id
,
2036 enum gpiod_flags flags
)
2038 return gpiod_get_index(dev
, con_id
, 0, flags
);
2040 EXPORT_SYMBOL_GPL(gpiod_get
);
2043 * gpiod_get_optional - obtain an optional GPIO for a given GPIO function
2044 * @dev: GPIO consumer, can be NULL for system-global GPIOs
2045 * @con_id: function within the GPIO consumer
2046 * @flags: optional GPIO initialization flags
2048 * This is equivalent to gpiod_get(), except that when no GPIO was assigned to
2049 * the requested function it will return NULL. This is convenient for drivers
2050 * that need to handle optional GPIOs.
2052 struct gpio_desc
*__must_check
gpiod_get_optional(struct device
*dev
,
2054 enum gpiod_flags flags
)
2056 return gpiod_get_index_optional(dev
, con_id
, 0, flags
);
2058 EXPORT_SYMBOL_GPL(gpiod_get_optional
);
2061 * gpiod_parse_flags - helper function to parse GPIO lookup flags
2062 * @desc: gpio to be setup
2063 * @lflags: gpio_lookup_flags - returned from of_find_gpio() or
2066 * Set the GPIO descriptor flags based on the given GPIO lookup flags.
2068 static void gpiod_parse_flags(struct gpio_desc
*desc
, unsigned long lflags
)
2070 if (lflags
& GPIO_ACTIVE_LOW
)
2071 set_bit(FLAG_ACTIVE_LOW
, &desc
->flags
);
2072 if (lflags
& GPIO_OPEN_DRAIN
)
2073 set_bit(FLAG_OPEN_DRAIN
, &desc
->flags
);
2074 if (lflags
& GPIO_OPEN_SOURCE
)
2075 set_bit(FLAG_OPEN_SOURCE
, &desc
->flags
);
2079 * gpiod_configure_flags - helper function to configure a given GPIO
2080 * @desc: gpio whose value will be assigned
2081 * @con_id: function within the GPIO consumer
2082 * @dflags: gpiod_flags - optional GPIO initialization flags
2084 * Return 0 on success, -ENOENT if no GPIO has been assigned to the
2085 * requested function and/or index, or another IS_ERR() code if an error
2086 * occurred while trying to acquire the GPIO.
2088 static int gpiod_configure_flags(struct gpio_desc
*desc
, const char *con_id
,
2089 enum gpiod_flags dflags
)
2093 /* No particular flag request, return here... */
2094 if (!(dflags
& GPIOD_FLAGS_BIT_DIR_SET
)) {
2095 pr_debug("no flags found for %s\n", con_id
);
2100 if (dflags
& GPIOD_FLAGS_BIT_DIR_OUT
)
2101 status
= gpiod_direction_output(desc
,
2102 dflags
& GPIOD_FLAGS_BIT_DIR_VAL
);
2104 status
= gpiod_direction_input(desc
);
2110 * gpiod_get_index - obtain a GPIO from a multi-index GPIO function
2111 * @dev: GPIO consumer, can be NULL for system-global GPIOs
2112 * @con_id: function within the GPIO consumer
2113 * @idx: index of the GPIO to obtain in the consumer
2114 * @flags: optional GPIO initialization flags
2116 * This variant of gpiod_get() allows to access GPIOs other than the first
2117 * defined one for functions that define several GPIOs.
2119 * Return a valid GPIO descriptor, -ENOENT if no GPIO has been assigned to the
2120 * requested function and/or index, or another IS_ERR() code if an error
2121 * occurred while trying to acquire the GPIO.
2123 struct gpio_desc
*__must_check
gpiod_get_index(struct device
*dev
,
2126 enum gpiod_flags flags
)
2128 struct gpio_desc
*desc
= NULL
;
2130 enum gpio_lookup_flags lookupflags
= 0;
2132 dev_dbg(dev
, "GPIO lookup for consumer %s\n", con_id
);
2135 /* Using device tree? */
2136 if (IS_ENABLED(CONFIG_OF
) && dev
->of_node
) {
2137 dev_dbg(dev
, "using device tree for GPIO lookup\n");
2138 desc
= of_find_gpio(dev
, con_id
, idx
, &lookupflags
);
2139 } else if (ACPI_COMPANION(dev
)) {
2140 dev_dbg(dev
, "using ACPI for GPIO lookup\n");
2141 desc
= acpi_find_gpio(dev
, con_id
, idx
, &lookupflags
);
2146 * Either we are not using DT or ACPI, or their lookup did not return
2147 * a result. In that case, use platform lookup as a fallback.
2149 if (!desc
|| desc
== ERR_PTR(-ENOENT
)) {
2150 dev_dbg(dev
, "using lookup tables for GPIO lookup\n");
2151 desc
= gpiod_find(dev
, con_id
, idx
, &lookupflags
);
2155 dev_dbg(dev
, "lookup for GPIO %s failed\n", con_id
);
2159 gpiod_parse_flags(desc
, lookupflags
);
2161 status
= gpiod_request(desc
, con_id
);
2163 return ERR_PTR(status
);
2165 status
= gpiod_configure_flags(desc
, con_id
, flags
);
2167 dev_dbg(dev
, "setup of GPIO %s failed\n", con_id
);
2169 return ERR_PTR(status
);
2174 EXPORT_SYMBOL_GPL(gpiod_get_index
);
2177 * fwnode_get_named_gpiod - obtain a GPIO from firmware node
2178 * @fwnode: handle of the firmware node
2179 * @propname: name of the firmware property representing the GPIO
2181 * This function can be used for drivers that get their configuration
2184 * Function properly finds the corresponding GPIO using whatever is the
2185 * underlying firmware interface and then makes sure that the GPIO
2186 * descriptor is requested before it is returned to the caller.
2188 * In case of error an ERR_PTR() is returned.
2190 struct gpio_desc
*fwnode_get_named_gpiod(struct fwnode_handle
*fwnode
,
2191 const char *propname
)
2193 struct gpio_desc
*desc
= ERR_PTR(-ENODEV
);
2194 bool active_low
= false;
2195 bool single_ended
= false;
2199 return ERR_PTR(-EINVAL
);
2201 if (is_of_node(fwnode
)) {
2202 enum of_gpio_flags flags
;
2204 desc
= of_get_named_gpiod_flags(to_of_node(fwnode
), propname
, 0,
2206 if (!IS_ERR(desc
)) {
2207 active_low
= flags
& OF_GPIO_ACTIVE_LOW
;
2208 single_ended
= flags
& OF_GPIO_SINGLE_ENDED
;
2210 } else if (is_acpi_node(fwnode
)) {
2211 struct acpi_gpio_info info
;
2213 desc
= acpi_node_get_gpiod(fwnode
, propname
, 0, &info
);
2215 active_low
= info
.active_low
;
2222 set_bit(FLAG_ACTIVE_LOW
, &desc
->flags
);
2226 set_bit(FLAG_OPEN_DRAIN
, &desc
->flags
);
2228 set_bit(FLAG_OPEN_SOURCE
, &desc
->flags
);
2231 ret
= gpiod_request(desc
, NULL
);
2233 return ERR_PTR(ret
);
2237 EXPORT_SYMBOL_GPL(fwnode_get_named_gpiod
);
2240 * gpiod_get_index_optional - obtain an optional GPIO from a multi-index GPIO
2242 * @dev: GPIO consumer, can be NULL for system-global GPIOs
2243 * @con_id: function within the GPIO consumer
2244 * @index: index of the GPIO to obtain in the consumer
2245 * @flags: optional GPIO initialization flags
2247 * This is equivalent to gpiod_get_index(), except that when no GPIO with the
2248 * specified index was assigned to the requested function it will return NULL.
2249 * This is convenient for drivers that need to handle optional GPIOs.
2251 struct gpio_desc
*__must_check
gpiod_get_index_optional(struct device
*dev
,
2254 enum gpiod_flags flags
)
2256 struct gpio_desc
*desc
;
2258 desc
= gpiod_get_index(dev
, con_id
, index
, flags
);
2260 if (PTR_ERR(desc
) == -ENOENT
)
2266 EXPORT_SYMBOL_GPL(gpiod_get_index_optional
);
2269 * gpiod_hog - Hog the specified GPIO desc given the provided flags
2270 * @desc: gpio whose value will be assigned
2271 * @name: gpio line name
2272 * @lflags: gpio_lookup_flags - returned from of_find_gpio() or
2274 * @dflags: gpiod_flags - optional GPIO initialization flags
2276 int gpiod_hog(struct gpio_desc
*desc
, const char *name
,
2277 unsigned long lflags
, enum gpiod_flags dflags
)
2279 struct gpio_chip
*chip
;
2280 struct gpio_desc
*local_desc
;
2284 chip
= gpiod_to_chip(desc
);
2285 hwnum
= gpio_chip_hwgpio(desc
);
2287 gpiod_parse_flags(desc
, lflags
);
2289 local_desc
= gpiochip_request_own_desc(chip
, hwnum
, name
);
2290 if (IS_ERR(local_desc
)) {
2291 pr_err("requesting hog GPIO %s (chip %s, offset %d) failed\n",
2292 name
, chip
->label
, hwnum
);
2293 return PTR_ERR(local_desc
);
2296 status
= gpiod_configure_flags(desc
, name
, dflags
);
2298 pr_err("setup of hog GPIO %s (chip %s, offset %d) failed\n",
2299 name
, chip
->label
, hwnum
);
2300 gpiochip_free_own_desc(desc
);
2304 /* Mark GPIO as hogged so it can be identified and removed later */
2305 set_bit(FLAG_IS_HOGGED
, &desc
->flags
);
2307 pr_info("GPIO line %d (%s) hogged as %s%s\n",
2308 desc_to_gpio(desc
), name
,
2309 (dflags
&GPIOD_FLAGS_BIT_DIR_OUT
) ? "output" : "input",
2310 (dflags
&GPIOD_FLAGS_BIT_DIR_OUT
) ?
2311 (dflags
&GPIOD_FLAGS_BIT_DIR_VAL
) ? "/high" : "/low":"");
2317 * gpiochip_free_hogs - Scan gpio-controller chip and release GPIO hog
2318 * @chip: gpio chip to act on
2320 * This is only used by of_gpiochip_remove to free hogged gpios
2322 static void gpiochip_free_hogs(struct gpio_chip
*chip
)
2326 for (id
= 0; id
< chip
->ngpio
; id
++) {
2327 if (test_bit(FLAG_IS_HOGGED
, &chip
->desc
[id
].flags
))
2328 gpiochip_free_own_desc(&chip
->desc
[id
]);
2333 * gpiod_get_array - obtain multiple GPIOs from a multi-index GPIO function
2334 * @dev: GPIO consumer, can be NULL for system-global GPIOs
2335 * @con_id: function within the GPIO consumer
2336 * @flags: optional GPIO initialization flags
2338 * This function acquires all the GPIOs defined under a given function.
2340 * Return a struct gpio_descs containing an array of descriptors, -ENOENT if
2341 * no GPIO has been assigned to the requested function, or another IS_ERR()
2342 * code if an error occurred while trying to acquire the GPIOs.
2344 struct gpio_descs
*__must_check
gpiod_get_array(struct device
*dev
,
2346 enum gpiod_flags flags
)
2348 struct gpio_desc
*desc
;
2349 struct gpio_descs
*descs
;
2352 count
= gpiod_count(dev
, con_id
);
2354 return ERR_PTR(count
);
2356 descs
= kzalloc(sizeof(*descs
) + sizeof(descs
->desc
[0]) * count
,
2359 return ERR_PTR(-ENOMEM
);
2361 for (descs
->ndescs
= 0; descs
->ndescs
< count
; ) {
2362 desc
= gpiod_get_index(dev
, con_id
, descs
->ndescs
, flags
);
2364 gpiod_put_array(descs
);
2365 return ERR_CAST(desc
);
2367 descs
->desc
[descs
->ndescs
] = desc
;
2372 EXPORT_SYMBOL_GPL(gpiod_get_array
);
2375 * gpiod_get_array_optional - obtain multiple GPIOs from a multi-index GPIO
2377 * @dev: GPIO consumer, can be NULL for system-global GPIOs
2378 * @con_id: function within the GPIO consumer
2379 * @flags: optional GPIO initialization flags
2381 * This is equivalent to gpiod_get_array(), except that when no GPIO was
2382 * assigned to the requested function it will return NULL.
2384 struct gpio_descs
*__must_check
gpiod_get_array_optional(struct device
*dev
,
2386 enum gpiod_flags flags
)
2388 struct gpio_descs
*descs
;
2390 descs
= gpiod_get_array(dev
, con_id
, flags
);
2391 if (IS_ERR(descs
) && (PTR_ERR(descs
) == -ENOENT
))
2396 EXPORT_SYMBOL_GPL(gpiod_get_array_optional
);
2399 * gpiod_put - dispose of a GPIO descriptor
2400 * @desc: GPIO descriptor to dispose of
2402 * No descriptor can be used after gpiod_put() has been called on it.
2404 void gpiod_put(struct gpio_desc
*desc
)
2408 EXPORT_SYMBOL_GPL(gpiod_put
);
2411 * gpiod_put_array - dispose of multiple GPIO descriptors
2412 * @descs: struct gpio_descs containing an array of descriptors
2414 void gpiod_put_array(struct gpio_descs
*descs
)
2418 for (i
= 0; i
< descs
->ndescs
; i
++)
2419 gpiod_put(descs
->desc
[i
]);
2423 EXPORT_SYMBOL_GPL(gpiod_put_array
);
2425 #ifdef CONFIG_DEBUG_FS
2427 static void gpiolib_dbg_show(struct seq_file
*s
, struct gpio_chip
*chip
)
2430 unsigned gpio
= chip
->base
;
2431 struct gpio_desc
*gdesc
= &chip
->desc
[0];
2435 for (i
= 0; i
< chip
->ngpio
; i
++, gpio
++, gdesc
++) {
2436 if (!test_bit(FLAG_REQUESTED
, &gdesc
->flags
)) {
2438 seq_printf(s
, " gpio-%-3d (%-20.20s)\n",
2444 gpiod_get_direction(gdesc
);
2445 is_out
= test_bit(FLAG_IS_OUT
, &gdesc
->flags
);
2446 is_irq
= test_bit(FLAG_USED_AS_IRQ
, &gdesc
->flags
);
2447 seq_printf(s
, " gpio-%-3d (%-20.20s|%-20.20s) %s %s %s",
2448 gpio
, gdesc
->name
? gdesc
->name
: "", gdesc
->label
,
2449 is_out
? "out" : "in ",
2451 ? (chip
->get(chip
, i
) ? "hi" : "lo")
2453 is_irq
? "IRQ" : " ");
2454 seq_printf(s
, "\n");
2458 static void *gpiolib_seq_start(struct seq_file
*s
, loff_t
*pos
)
2460 unsigned long flags
;
2461 struct gpio_chip
*chip
= NULL
;
2462 loff_t index
= *pos
;
2466 spin_lock_irqsave(&gpio_lock
, flags
);
2467 list_for_each_entry(chip
, &gpio_chips
, list
)
2469 spin_unlock_irqrestore(&gpio_lock
, flags
);
2472 spin_unlock_irqrestore(&gpio_lock
, flags
);
2477 static void *gpiolib_seq_next(struct seq_file
*s
, void *v
, loff_t
*pos
)
2479 unsigned long flags
;
2480 struct gpio_chip
*chip
= v
;
2483 spin_lock_irqsave(&gpio_lock
, flags
);
2484 if (list_is_last(&chip
->list
, &gpio_chips
))
2487 ret
= list_entry(chip
->list
.next
, struct gpio_chip
, list
);
2488 spin_unlock_irqrestore(&gpio_lock
, flags
);
2496 static void gpiolib_seq_stop(struct seq_file
*s
, void *v
)
2500 static int gpiolib_seq_show(struct seq_file
*s
, void *v
)
2502 struct gpio_chip
*chip
= v
;
2505 seq_printf(s
, "%sGPIOs %d-%d", (char *)s
->private,
2506 chip
->base
, chip
->base
+ chip
->ngpio
- 1);
2509 seq_printf(s
, ", %s/%s", dev
->bus
? dev
->bus
->name
: "no-bus",
2512 seq_printf(s
, ", %s", chip
->label
);
2513 if (chip
->can_sleep
)
2514 seq_printf(s
, ", can sleep");
2515 seq_printf(s
, ":\n");
2518 chip
->dbg_show(s
, chip
);
2520 gpiolib_dbg_show(s
, chip
);
2525 static const struct seq_operations gpiolib_seq_ops
= {
2526 .start
= gpiolib_seq_start
,
2527 .next
= gpiolib_seq_next
,
2528 .stop
= gpiolib_seq_stop
,
2529 .show
= gpiolib_seq_show
,
2532 static int gpiolib_open(struct inode
*inode
, struct file
*file
)
2534 return seq_open(file
, &gpiolib_seq_ops
);
2537 static const struct file_operations gpiolib_operations
= {
2538 .owner
= THIS_MODULE
,
2539 .open
= gpiolib_open
,
2541 .llseek
= seq_lseek
,
2542 .release
= seq_release
,
2545 static int __init
gpiolib_debugfs_init(void)
2547 /* /sys/kernel/debug/gpio */
2548 (void) debugfs_create_file("gpio", S_IFREG
| S_IRUGO
,
2549 NULL
, NULL
, &gpiolib_operations
);
2552 subsys_initcall(gpiolib_debugfs_init
);
2554 #endif /* DEBUG_FS */