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
) {
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
->dev
, "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
->dev
&& chip
->dev
->driver
)
352 chip
->owner
= chip
->dev
->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
->dev
, "REMOVING GPIOCHIP WITH GPIOS STILL REQUESTED\n");
432 EXPORT_SYMBOL_GPL(gpiochip_remove
);
435 * gpiochip_find() - iterator for locating a specific gpio_chip
436 * @data: data to pass to match function
437 * @callback: Callback function to check gpio_chip
439 * Similar to bus_find_device. It returns a reference to a gpio_chip as
440 * determined by a user supplied @match callback. The callback should return
441 * 0 if the device doesn't match and non-zero if it does. If the callback is
442 * non-zero, this function will return to the caller and not iterate over any
445 struct gpio_chip
*gpiochip_find(void *data
,
446 int (*match
)(struct gpio_chip
*chip
,
449 struct gpio_chip
*chip
;
452 spin_lock_irqsave(&gpio_lock
, flags
);
453 list_for_each_entry(chip
, &gpio_chips
, list
)
454 if (match(chip
, data
))
458 if (&chip
->list
== &gpio_chips
)
460 spin_unlock_irqrestore(&gpio_lock
, flags
);
464 EXPORT_SYMBOL_GPL(gpiochip_find
);
466 static int gpiochip_match_name(struct gpio_chip
*chip
, void *data
)
468 const char *name
= data
;
470 return !strcmp(chip
->label
, name
);
473 static struct gpio_chip
*find_chip_by_name(const char *name
)
475 return gpiochip_find((void *)name
, gpiochip_match_name
);
478 #ifdef CONFIG_GPIOLIB_IRQCHIP
481 * The following is irqchip helper code for gpiochips.
485 * gpiochip_set_chained_irqchip() - sets a chained irqchip to a gpiochip
486 * @gpiochip: the gpiochip to set the irqchip chain to
487 * @irqchip: the irqchip to chain to the gpiochip
488 * @parent_irq: the irq number corresponding to the parent IRQ for this
490 * @parent_handler: the parent interrupt handler for the accumulated IRQ
491 * coming out of the gpiochip. If the interrupt is nested rather than
492 * cascaded, pass NULL in this handler argument
494 void gpiochip_set_chained_irqchip(struct gpio_chip
*gpiochip
,
495 struct irq_chip
*irqchip
,
497 irq_flow_handler_t parent_handler
)
501 if (!gpiochip
->irqdomain
) {
502 chip_err(gpiochip
, "called %s before setting up irqchip\n",
507 if (parent_handler
) {
508 if (gpiochip
->can_sleep
) {
510 "you cannot have chained interrupts on a "
511 "chip that may sleep\n");
515 * The parent irqchip is already using the chip_data for this
516 * irqchip, so our callbacks simply use the handler_data.
518 irq_set_chained_handler_and_data(parent_irq
, parent_handler
,
521 gpiochip
->irq_parent
= parent_irq
;
524 /* Set the parent IRQ for all affected IRQs */
525 for (offset
= 0; offset
< gpiochip
->ngpio
; offset
++)
526 irq_set_parent(irq_find_mapping(gpiochip
->irqdomain
, offset
),
529 EXPORT_SYMBOL_GPL(gpiochip_set_chained_irqchip
);
532 * gpiochip_irq_map() - maps an IRQ into a GPIO irqchip
533 * @d: the irqdomain used by this irqchip
534 * @irq: the global irq number used by this GPIO irqchip irq
535 * @hwirq: the local IRQ/GPIO line offset on this gpiochip
537 * This function will set up the mapping for a certain IRQ line on a
538 * gpiochip by assigning the gpiochip as chip data, and using the irqchip
539 * stored inside the gpiochip.
541 static int gpiochip_irq_map(struct irq_domain
*d
, unsigned int irq
,
542 irq_hw_number_t hwirq
)
544 struct gpio_chip
*chip
= d
->host_data
;
546 irq_set_chip_data(irq
, chip
);
548 * This lock class tells lockdep that GPIO irqs are in a different
549 * category than their parents, so it won't report false recursion.
551 irq_set_lockdep_class(irq
, chip
->lock_key
);
552 irq_set_chip_and_handler(irq
, chip
->irqchip
, chip
->irq_handler
);
553 /* Chips that can sleep need nested thread handlers */
554 if (chip
->can_sleep
&& !chip
->irq_not_threaded
)
555 irq_set_nested_thread(irq
, 1);
556 irq_set_noprobe(irq
);
559 * No set-up of the hardware will happen if IRQ_TYPE_NONE
560 * is passed as default type.
562 if (chip
->irq_default_type
!= IRQ_TYPE_NONE
)
563 irq_set_irq_type(irq
, chip
->irq_default_type
);
568 static void gpiochip_irq_unmap(struct irq_domain
*d
, unsigned int irq
)
570 struct gpio_chip
*chip
= d
->host_data
;
573 irq_set_nested_thread(irq
, 0);
574 irq_set_chip_and_handler(irq
, NULL
, NULL
);
575 irq_set_chip_data(irq
, NULL
);
578 static const struct irq_domain_ops gpiochip_domain_ops
= {
579 .map
= gpiochip_irq_map
,
580 .unmap
= gpiochip_irq_unmap
,
581 /* Virtually all GPIO irqchips are twocell:ed */
582 .xlate
= irq_domain_xlate_twocell
,
585 static int gpiochip_irq_reqres(struct irq_data
*d
)
587 struct gpio_chip
*chip
= irq_data_get_irq_chip_data(d
);
589 if (!try_module_get(chip
->owner
))
592 if (gpiochip_lock_as_irq(chip
, d
->hwirq
)) {
594 "unable to lock HW IRQ %lu for IRQ\n",
596 module_put(chip
->owner
);
602 static void gpiochip_irq_relres(struct irq_data
*d
)
604 struct gpio_chip
*chip
= irq_data_get_irq_chip_data(d
);
606 gpiochip_unlock_as_irq(chip
, d
->hwirq
);
607 module_put(chip
->owner
);
610 static int gpiochip_to_irq(struct gpio_chip
*chip
, unsigned offset
)
612 return irq_find_mapping(chip
->irqdomain
, offset
);
616 * gpiochip_irqchip_remove() - removes an irqchip added to a gpiochip
617 * @gpiochip: the gpiochip to remove the irqchip from
619 * This is called only from gpiochip_remove()
621 static void gpiochip_irqchip_remove(struct gpio_chip
*gpiochip
)
625 acpi_gpiochip_free_interrupts(gpiochip
);
627 if (gpiochip
->irq_parent
) {
628 irq_set_chained_handler(gpiochip
->irq_parent
, NULL
);
629 irq_set_handler_data(gpiochip
->irq_parent
, NULL
);
632 /* Remove all IRQ mappings and delete the domain */
633 if (gpiochip
->irqdomain
) {
634 for (offset
= 0; offset
< gpiochip
->ngpio
; offset
++)
636 irq_find_mapping(gpiochip
->irqdomain
, offset
));
637 irq_domain_remove(gpiochip
->irqdomain
);
640 if (gpiochip
->irqchip
) {
641 gpiochip
->irqchip
->irq_request_resources
= NULL
;
642 gpiochip
->irqchip
->irq_release_resources
= NULL
;
643 gpiochip
->irqchip
= NULL
;
648 * gpiochip_irqchip_add() - adds an irqchip to a gpiochip
649 * @gpiochip: the gpiochip to add the irqchip to
650 * @irqchip: the irqchip to add to the gpiochip
651 * @first_irq: if not dynamically assigned, the base (first) IRQ to
652 * allocate gpiochip irqs from
653 * @handler: the irq handler to use (often a predefined irq core function)
654 * @type: the default type for IRQs on this irqchip, pass IRQ_TYPE_NONE
655 * to have the core avoid setting up any default type in the hardware.
656 * @lock_key: lockdep class
658 * This function closely associates a certain irqchip with a certain
659 * gpiochip, providing an irq domain to translate the local IRQs to
660 * global irqs in the gpiolib core, and making sure that the gpiochip
661 * is passed as chip data to all related functions. Driver callbacks
662 * need to use container_of() to get their local state containers back
663 * from the gpiochip passed as chip data. An irqdomain will be stored
664 * in the gpiochip that shall be used by the driver to handle IRQ number
665 * translation. The gpiochip will need to be initialized and registered
666 * before calling this function.
668 * This function will handle two cell:ed simple IRQs and assumes all
669 * the pins on the gpiochip can generate a unique IRQ. Everything else
670 * need to be open coded.
672 int _gpiochip_irqchip_add(struct gpio_chip
*gpiochip
,
673 struct irq_chip
*irqchip
,
674 unsigned int first_irq
,
675 irq_flow_handler_t handler
,
677 struct lock_class_key
*lock_key
)
679 struct device_node
*of_node
;
681 unsigned irq_base
= 0;
683 if (!gpiochip
|| !irqchip
)
686 if (!gpiochip
->dev
) {
687 pr_err("missing gpiochip .dev parent pointer\n");
690 of_node
= gpiochip
->dev
->of_node
;
691 #ifdef CONFIG_OF_GPIO
693 * If the gpiochip has an assigned OF node this takes precedence
694 * FIXME: get rid of this and use gpiochip->dev->of_node everywhere
696 if (gpiochip
->of_node
)
697 of_node
= gpiochip
->of_node
;
699 gpiochip
->irqchip
= irqchip
;
700 gpiochip
->irq_handler
= handler
;
701 gpiochip
->irq_default_type
= type
;
702 gpiochip
->to_irq
= gpiochip_to_irq
;
703 gpiochip
->lock_key
= lock_key
;
704 gpiochip
->irqdomain
= irq_domain_add_simple(of_node
,
705 gpiochip
->ngpio
, first_irq
,
706 &gpiochip_domain_ops
, gpiochip
);
707 if (!gpiochip
->irqdomain
) {
708 gpiochip
->irqchip
= NULL
;
713 * It is possible for a driver to override this, but only if the
714 * alternative functions are both implemented.
716 if (!irqchip
->irq_request_resources
&&
717 !irqchip
->irq_release_resources
) {
718 irqchip
->irq_request_resources
= gpiochip_irq_reqres
;
719 irqchip
->irq_release_resources
= gpiochip_irq_relres
;
723 * Prepare the mapping since the irqchip shall be orthogonal to
724 * any gpiochip calls. If the first_irq was zero, this is
725 * necessary to allocate descriptors for all IRQs.
727 for (offset
= 0; offset
< gpiochip
->ngpio
; offset
++) {
728 irq_base
= irq_create_mapping(gpiochip
->irqdomain
, offset
);
731 * Store the base into the gpiochip to be used when
732 * unmapping the irqs.
734 gpiochip
->irq_base
= irq_base
;
737 acpi_gpiochip_request_interrupts(gpiochip
);
741 EXPORT_SYMBOL_GPL(_gpiochip_irqchip_add
);
743 #else /* CONFIG_GPIOLIB_IRQCHIP */
745 static void gpiochip_irqchip_remove(struct gpio_chip
*gpiochip
) {}
747 #endif /* CONFIG_GPIOLIB_IRQCHIP */
750 * gpiochip_generic_request() - request the gpio function for a pin
751 * @chip: the gpiochip owning the GPIO
752 * @offset: the offset of the GPIO to request for GPIO function
754 int gpiochip_generic_request(struct gpio_chip
*chip
, unsigned offset
)
756 return pinctrl_request_gpio(chip
->base
+ offset
);
758 EXPORT_SYMBOL_GPL(gpiochip_generic_request
);
761 * gpiochip_generic_free() - free the gpio function from a pin
762 * @chip: the gpiochip to request the gpio function for
763 * @offset: the offset of the GPIO to free from GPIO function
765 void gpiochip_generic_free(struct gpio_chip
*chip
, unsigned offset
)
767 pinctrl_free_gpio(chip
->base
+ offset
);
769 EXPORT_SYMBOL_GPL(gpiochip_generic_free
);
771 #ifdef CONFIG_PINCTRL
774 * gpiochip_add_pingroup_range() - add a range for GPIO <-> pin mapping
775 * @chip: the gpiochip to add the range for
776 * @pctldev: the pin controller to map to
777 * @gpio_offset: the start offset in the current gpio_chip number space
778 * @pin_group: name of the pin group inside the pin controller
780 int gpiochip_add_pingroup_range(struct gpio_chip
*chip
,
781 struct pinctrl_dev
*pctldev
,
782 unsigned int gpio_offset
, const char *pin_group
)
784 struct gpio_pin_range
*pin_range
;
787 pin_range
= kzalloc(sizeof(*pin_range
), GFP_KERNEL
);
789 chip_err(chip
, "failed to allocate pin ranges\n");
793 /* Use local offset as range ID */
794 pin_range
->range
.id
= gpio_offset
;
795 pin_range
->range
.gc
= chip
;
796 pin_range
->range
.name
= chip
->label
;
797 pin_range
->range
.base
= chip
->base
+ gpio_offset
;
798 pin_range
->pctldev
= pctldev
;
800 ret
= pinctrl_get_group_pins(pctldev
, pin_group
,
801 &pin_range
->range
.pins
,
802 &pin_range
->range
.npins
);
808 pinctrl_add_gpio_range(pctldev
, &pin_range
->range
);
810 chip_dbg(chip
, "created GPIO range %d->%d ==> %s PINGRP %s\n",
811 gpio_offset
, gpio_offset
+ pin_range
->range
.npins
- 1,
812 pinctrl_dev_get_devname(pctldev
), pin_group
);
814 list_add_tail(&pin_range
->node
, &chip
->pin_ranges
);
818 EXPORT_SYMBOL_GPL(gpiochip_add_pingroup_range
);
821 * gpiochip_add_pin_range() - add a range for GPIO <-> pin mapping
822 * @chip: the gpiochip to add the range for
823 * @pinctrl_name: the dev_name() of the pin controller to map to
824 * @gpio_offset: the start offset in the current gpio_chip number space
825 * @pin_offset: the start offset in the pin controller number space
826 * @npins: the number of pins from the offset of each pin space (GPIO and
827 * pin controller) to accumulate in this range
829 int gpiochip_add_pin_range(struct gpio_chip
*chip
, const char *pinctl_name
,
830 unsigned int gpio_offset
, unsigned int pin_offset
,
833 struct gpio_pin_range
*pin_range
;
836 pin_range
= kzalloc(sizeof(*pin_range
), GFP_KERNEL
);
838 chip_err(chip
, "failed to allocate pin ranges\n");
842 /* Use local offset as range ID */
843 pin_range
->range
.id
= gpio_offset
;
844 pin_range
->range
.gc
= chip
;
845 pin_range
->range
.name
= chip
->label
;
846 pin_range
->range
.base
= chip
->base
+ gpio_offset
;
847 pin_range
->range
.pin_base
= pin_offset
;
848 pin_range
->range
.npins
= npins
;
849 pin_range
->pctldev
= pinctrl_find_and_add_gpio_range(pinctl_name
,
851 if (IS_ERR(pin_range
->pctldev
)) {
852 ret
= PTR_ERR(pin_range
->pctldev
);
853 chip_err(chip
, "could not create pin range\n");
857 chip_dbg(chip
, "created GPIO range %d->%d ==> %s PIN %d->%d\n",
858 gpio_offset
, gpio_offset
+ npins
- 1,
860 pin_offset
, pin_offset
+ npins
- 1);
862 list_add_tail(&pin_range
->node
, &chip
->pin_ranges
);
866 EXPORT_SYMBOL_GPL(gpiochip_add_pin_range
);
869 * gpiochip_remove_pin_ranges() - remove all the GPIO <-> pin mappings
870 * @chip: the chip to remove all the mappings for
872 void gpiochip_remove_pin_ranges(struct gpio_chip
*chip
)
874 struct gpio_pin_range
*pin_range
, *tmp
;
876 list_for_each_entry_safe(pin_range
, tmp
, &chip
->pin_ranges
, node
) {
877 list_del(&pin_range
->node
);
878 pinctrl_remove_gpio_range(pin_range
->pctldev
,
883 EXPORT_SYMBOL_GPL(gpiochip_remove_pin_ranges
);
885 #endif /* CONFIG_PINCTRL */
887 /* These "optional" allocation calls help prevent drivers from stomping
888 * on each other, and help provide better diagnostics in debugfs.
889 * They're called even less than the "set direction" calls.
891 static int __gpiod_request(struct gpio_desc
*desc
, const char *label
)
893 struct gpio_chip
*chip
= desc
->chip
;
897 spin_lock_irqsave(&gpio_lock
, flags
);
899 /* NOTE: gpio_request() can be called in early boot,
900 * before IRQs are enabled, for non-sleeping (SOC) GPIOs.
903 if (test_and_set_bit(FLAG_REQUESTED
, &desc
->flags
) == 0) {
904 desc_set_label(desc
, label
? : "?");
912 /* chip->request may sleep */
913 spin_unlock_irqrestore(&gpio_lock
, flags
);
914 status
= chip
->request(chip
, gpio_chip_hwgpio(desc
));
915 spin_lock_irqsave(&gpio_lock
, flags
);
918 desc_set_label(desc
, NULL
);
919 clear_bit(FLAG_REQUESTED
, &desc
->flags
);
923 if (chip
->get_direction
) {
924 /* chip->get_direction may sleep */
925 spin_unlock_irqrestore(&gpio_lock
, flags
);
926 gpiod_get_direction(desc
);
927 spin_lock_irqsave(&gpio_lock
, flags
);
931 /* Clear flags that might have been set by the caller before
932 * requesting the GPIO.
934 clear_bit(FLAG_ACTIVE_LOW
, &desc
->flags
);
935 clear_bit(FLAG_OPEN_DRAIN
, &desc
->flags
);
936 clear_bit(FLAG_OPEN_SOURCE
, &desc
->flags
);
938 spin_unlock_irqrestore(&gpio_lock
, flags
);
942 int gpiod_request(struct gpio_desc
*desc
, const char *label
)
944 int status
= -EPROBE_DEFER
;
945 struct gpio_chip
*chip
;
948 pr_warn("%s: invalid GPIO\n", __func__
);
956 if (try_module_get(chip
->owner
)) {
957 status
= __gpiod_request(desc
, label
);
959 module_put(chip
->owner
);
964 gpiod_dbg(desc
, "%s: status %d\n", __func__
, status
);
969 static bool __gpiod_free(struct gpio_desc
*desc
)
973 struct gpio_chip
*chip
;
977 gpiod_unexport(desc
);
979 spin_lock_irqsave(&gpio_lock
, flags
);
982 if (chip
&& test_bit(FLAG_REQUESTED
, &desc
->flags
)) {
984 spin_unlock_irqrestore(&gpio_lock
, flags
);
985 might_sleep_if(chip
->can_sleep
);
986 chip
->free(chip
, gpio_chip_hwgpio(desc
));
987 spin_lock_irqsave(&gpio_lock
, flags
);
989 desc_set_label(desc
, NULL
);
990 clear_bit(FLAG_ACTIVE_LOW
, &desc
->flags
);
991 clear_bit(FLAG_REQUESTED
, &desc
->flags
);
992 clear_bit(FLAG_OPEN_DRAIN
, &desc
->flags
);
993 clear_bit(FLAG_OPEN_SOURCE
, &desc
->flags
);
994 clear_bit(FLAG_IS_HOGGED
, &desc
->flags
);
998 spin_unlock_irqrestore(&gpio_lock
, flags
);
1002 void gpiod_free(struct gpio_desc
*desc
)
1004 if (desc
&& __gpiod_free(desc
))
1005 module_put(desc
->chip
->owner
);
1007 WARN_ON(extra_checks
);
1011 * gpiochip_is_requested - return string iff signal was requested
1012 * @chip: controller managing the signal
1013 * @offset: of signal within controller's 0..(ngpio - 1) range
1015 * Returns NULL if the GPIO is not currently requested, else a string.
1016 * The string returned is the label passed to gpio_request(); if none has been
1017 * passed it is a meaningless, non-NULL constant.
1019 * This function is for use by GPIO controller drivers. The label can
1020 * help with diagnostics, and knowing that the signal is used as a GPIO
1021 * can help avoid accidentally multiplexing it to another controller.
1023 const char *gpiochip_is_requested(struct gpio_chip
*chip
, unsigned offset
)
1025 struct gpio_desc
*desc
;
1027 if (offset
>= chip
->ngpio
)
1030 desc
= &chip
->desc
[offset
];
1032 if (test_bit(FLAG_REQUESTED
, &desc
->flags
) == 0)
1036 EXPORT_SYMBOL_GPL(gpiochip_is_requested
);
1039 * gpiochip_request_own_desc - Allow GPIO chip to request its own descriptor
1040 * @desc: GPIO descriptor to request
1041 * @label: label for the GPIO
1043 * Function allows GPIO chip drivers to request and use their own GPIO
1044 * descriptors via gpiolib API. Difference to gpiod_request() is that this
1045 * function will not increase reference count of the GPIO chip module. This
1046 * allows the GPIO chip module to be unloaded as needed (we assume that the
1047 * GPIO chip driver handles freeing the GPIOs it has requested).
1049 struct gpio_desc
*gpiochip_request_own_desc(struct gpio_chip
*chip
, u16 hwnum
,
1052 struct gpio_desc
*desc
= gpiochip_get_desc(chip
, hwnum
);
1056 chip_err(chip
, "failed to get GPIO descriptor\n");
1060 err
= __gpiod_request(desc
, label
);
1062 return ERR_PTR(err
);
1066 EXPORT_SYMBOL_GPL(gpiochip_request_own_desc
);
1069 * gpiochip_free_own_desc - Free GPIO requested by the chip driver
1070 * @desc: GPIO descriptor to free
1072 * Function frees the given GPIO requested previously with
1073 * gpiochip_request_own_desc().
1075 void gpiochip_free_own_desc(struct gpio_desc
*desc
)
1080 EXPORT_SYMBOL_GPL(gpiochip_free_own_desc
);
1082 /* Drivers MUST set GPIO direction before making get/set calls. In
1083 * some cases this is done in early boot, before IRQs are enabled.
1085 * As a rule these aren't called more than once (except for drivers
1086 * using the open-drain emulation idiom) so these are natural places
1087 * to accumulate extra debugging checks. Note that we can't (yet)
1088 * rely on gpio_request() having been called beforehand.
1092 * gpiod_direction_input - set the GPIO direction to input
1093 * @desc: GPIO to set to input
1095 * Set the direction of the passed GPIO to input, such as gpiod_get_value() can
1096 * be called safely on it.
1098 * Return 0 in case of success, else an error code.
1100 int gpiod_direction_input(struct gpio_desc
*desc
)
1102 struct gpio_chip
*chip
;
1103 int status
= -EINVAL
;
1105 if (!desc
|| !desc
->chip
) {
1106 pr_warn("%s: invalid GPIO\n", __func__
);
1111 if (!chip
->get
|| !chip
->direction_input
) {
1113 "%s: missing get() or direction_input() operations\n",
1118 status
= chip
->direction_input(chip
, gpio_chip_hwgpio(desc
));
1120 clear_bit(FLAG_IS_OUT
, &desc
->flags
);
1122 trace_gpio_direction(desc_to_gpio(desc
), 1, status
);
1126 EXPORT_SYMBOL_GPL(gpiod_direction_input
);
1128 static int _gpiod_direction_output_raw(struct gpio_desc
*desc
, int value
)
1130 struct gpio_chip
*chip
;
1131 int status
= -EINVAL
;
1133 /* GPIOs used for IRQs shall not be set as output */
1134 if (test_bit(FLAG_USED_AS_IRQ
, &desc
->flags
)) {
1136 "%s: tried to set a GPIO tied to an IRQ as output\n",
1141 /* Open drain pin should not be driven to 1 */
1142 if (value
&& test_bit(FLAG_OPEN_DRAIN
, &desc
->flags
))
1143 return gpiod_direction_input(desc
);
1145 /* Open source pin should not be driven to 0 */
1146 if (!value
&& test_bit(FLAG_OPEN_SOURCE
, &desc
->flags
))
1147 return gpiod_direction_input(desc
);
1150 if (!chip
->set
|| !chip
->direction_output
) {
1152 "%s: missing set() or direction_output() operations\n",
1157 status
= chip
->direction_output(chip
, gpio_chip_hwgpio(desc
), value
);
1159 set_bit(FLAG_IS_OUT
, &desc
->flags
);
1160 trace_gpio_value(desc_to_gpio(desc
), 0, value
);
1161 trace_gpio_direction(desc_to_gpio(desc
), 0, status
);
1166 * gpiod_direction_output_raw - set the GPIO direction to output
1167 * @desc: GPIO to set to output
1168 * @value: initial output value of the GPIO
1170 * Set the direction of the passed GPIO to output, such as gpiod_set_value() can
1171 * be called safely on it. The initial value of the output must be specified
1172 * as raw value on the physical line without regard for the ACTIVE_LOW status.
1174 * Return 0 in case of success, else an error code.
1176 int gpiod_direction_output_raw(struct gpio_desc
*desc
, int value
)
1178 if (!desc
|| !desc
->chip
) {
1179 pr_warn("%s: invalid GPIO\n", __func__
);
1182 return _gpiod_direction_output_raw(desc
, value
);
1184 EXPORT_SYMBOL_GPL(gpiod_direction_output_raw
);
1187 * gpiod_direction_output - set the GPIO direction to output
1188 * @desc: GPIO to set to output
1189 * @value: initial output value of the GPIO
1191 * Set the direction of the passed GPIO to output, such as gpiod_set_value() can
1192 * be called safely on it. The initial value of the output must be specified
1193 * as the logical value of the GPIO, i.e. taking its ACTIVE_LOW status into
1196 * Return 0 in case of success, else an error code.
1198 int gpiod_direction_output(struct gpio_desc
*desc
, int value
)
1200 if (!desc
|| !desc
->chip
) {
1201 pr_warn("%s: invalid GPIO\n", __func__
);
1204 if (test_bit(FLAG_ACTIVE_LOW
, &desc
->flags
))
1206 return _gpiod_direction_output_raw(desc
, value
);
1208 EXPORT_SYMBOL_GPL(gpiod_direction_output
);
1211 * gpiod_set_debounce - sets @debounce time for a @gpio
1212 * @gpio: the gpio to set debounce time
1213 * @debounce: debounce time is microseconds
1215 * returns -ENOTSUPP if the controller does not support setting
1218 int gpiod_set_debounce(struct gpio_desc
*desc
, unsigned debounce
)
1220 struct gpio_chip
*chip
;
1222 if (!desc
|| !desc
->chip
) {
1223 pr_warn("%s: invalid GPIO\n", __func__
);
1228 if (!chip
->set
|| !chip
->set_debounce
) {
1230 "%s: missing set() or set_debounce() operations\n",
1235 return chip
->set_debounce(chip
, gpio_chip_hwgpio(desc
), debounce
);
1237 EXPORT_SYMBOL_GPL(gpiod_set_debounce
);
1240 * gpiod_is_active_low - test whether a GPIO is active-low or not
1241 * @desc: the gpio descriptor to test
1243 * Returns 1 if the GPIO is active-low, 0 otherwise.
1245 int gpiod_is_active_low(const struct gpio_desc
*desc
)
1247 return test_bit(FLAG_ACTIVE_LOW
, &desc
->flags
);
1249 EXPORT_SYMBOL_GPL(gpiod_is_active_low
);
1251 /* I/O calls are only valid after configuration completed; the relevant
1252 * "is this a valid GPIO" error checks should already have been done.
1254 * "Get" operations are often inlinable as reading a pin value register,
1255 * and masking the relevant bit in that register.
1257 * When "set" operations are inlinable, they involve writing that mask to
1258 * one register to set a low value, or a different register to set it high.
1259 * Otherwise locking is needed, so there may be little value to inlining.
1261 *------------------------------------------------------------------------
1263 * IMPORTANT!!! The hot paths -- get/set value -- assume that callers
1264 * have requested the GPIO. That can include implicit requesting by
1265 * a direction setting call. Marking a gpio as requested locks its chip
1266 * in memory, guaranteeing that these table lookups need no more locking
1267 * and that gpiochip_remove() will fail.
1269 * REVISIT when debugging, consider adding some instrumentation to ensure
1270 * that the GPIO was actually requested.
1273 static int _gpiod_get_raw_value(const struct gpio_desc
*desc
)
1275 struct gpio_chip
*chip
;
1280 offset
= gpio_chip_hwgpio(desc
);
1281 value
= chip
->get
? chip
->get(chip
, offset
) : -EIO
;
1282 value
= value
< 0 ? value
: !!value
;
1283 trace_gpio_value(desc_to_gpio(desc
), 1, value
);
1288 * gpiod_get_raw_value() - return a gpio's raw value
1289 * @desc: gpio whose value will be returned
1291 * Return the GPIO's raw value, i.e. the value of the physical line disregarding
1292 * its ACTIVE_LOW status, or negative errno on failure.
1294 * This function should be called from contexts where we cannot sleep, and will
1295 * complain if the GPIO chip functions potentially sleep.
1297 int gpiod_get_raw_value(const struct gpio_desc
*desc
)
1301 /* Should be using gpio_get_value_cansleep() */
1302 WARN_ON(desc
->chip
->can_sleep
);
1303 return _gpiod_get_raw_value(desc
);
1305 EXPORT_SYMBOL_GPL(gpiod_get_raw_value
);
1308 * gpiod_get_value() - return a gpio's value
1309 * @desc: gpio whose value will be returned
1311 * Return the GPIO's logical value, i.e. taking the ACTIVE_LOW status into
1312 * account, or negative errno on failure.
1314 * This function should be called from contexts where we cannot sleep, and will
1315 * complain if the GPIO chip functions potentially sleep.
1317 int gpiod_get_value(const struct gpio_desc
*desc
)
1322 /* Should be using gpio_get_value_cansleep() */
1323 WARN_ON(desc
->chip
->can_sleep
);
1325 value
= _gpiod_get_raw_value(desc
);
1329 if (test_bit(FLAG_ACTIVE_LOW
, &desc
->flags
))
1334 EXPORT_SYMBOL_GPL(gpiod_get_value
);
1337 * _gpio_set_open_drain_value() - Set the open drain gpio's value.
1338 * @desc: gpio descriptor whose state need to be set.
1339 * @value: Non-zero for setting it HIGH otherwise it will set to LOW.
1341 static void _gpio_set_open_drain_value(struct gpio_desc
*desc
, bool value
)
1344 struct gpio_chip
*chip
= desc
->chip
;
1345 int offset
= gpio_chip_hwgpio(desc
);
1348 err
= chip
->direction_input(chip
, offset
);
1350 clear_bit(FLAG_IS_OUT
, &desc
->flags
);
1352 err
= chip
->direction_output(chip
, offset
, 0);
1354 set_bit(FLAG_IS_OUT
, &desc
->flags
);
1356 trace_gpio_direction(desc_to_gpio(desc
), value
, err
);
1359 "%s: Error in set_value for open drain err %d\n",
1364 * _gpio_set_open_source_value() - Set the open source gpio's value.
1365 * @desc: gpio descriptor whose state need to be set.
1366 * @value: Non-zero for setting it HIGH otherwise it will set to LOW.
1368 static void _gpio_set_open_source_value(struct gpio_desc
*desc
, bool value
)
1371 struct gpio_chip
*chip
= desc
->chip
;
1372 int offset
= gpio_chip_hwgpio(desc
);
1375 err
= chip
->direction_output(chip
, offset
, 1);
1377 set_bit(FLAG_IS_OUT
, &desc
->flags
);
1379 err
= chip
->direction_input(chip
, offset
);
1381 clear_bit(FLAG_IS_OUT
, &desc
->flags
);
1383 trace_gpio_direction(desc_to_gpio(desc
), !value
, err
);
1386 "%s: Error in set_value for open source err %d\n",
1390 static void _gpiod_set_raw_value(struct gpio_desc
*desc
, bool value
)
1392 struct gpio_chip
*chip
;
1395 trace_gpio_value(desc_to_gpio(desc
), 0, value
);
1396 if (test_bit(FLAG_OPEN_DRAIN
, &desc
->flags
))
1397 _gpio_set_open_drain_value(desc
, value
);
1398 else if (test_bit(FLAG_OPEN_SOURCE
, &desc
->flags
))
1399 _gpio_set_open_source_value(desc
, value
);
1401 chip
->set(chip
, gpio_chip_hwgpio(desc
), value
);
1405 * set multiple outputs on the same chip;
1406 * use the chip's set_multiple function if available;
1407 * otherwise set the outputs sequentially;
1408 * @mask: bit mask array; one bit per output; BITS_PER_LONG bits per word
1409 * defines which outputs are to be changed
1410 * @bits: bit value array; one bit per output; BITS_PER_LONG bits per word
1411 * defines the values the outputs specified by mask are to be set to
1413 static void gpio_chip_set_multiple(struct gpio_chip
*chip
,
1414 unsigned long *mask
, unsigned long *bits
)
1416 if (chip
->set_multiple
) {
1417 chip
->set_multiple(chip
, mask
, bits
);
1420 for (i
= 0; i
< chip
->ngpio
; i
++) {
1421 if (mask
[BIT_WORD(i
)] == 0) {
1422 /* no more set bits in this mask word;
1423 * skip ahead to the next word */
1424 i
= (BIT_WORD(i
) + 1) * BITS_PER_LONG
- 1;
1427 /* set outputs if the corresponding mask bit is set */
1428 if (__test_and_clear_bit(i
, mask
))
1429 chip
->set(chip
, i
, test_bit(i
, bits
));
1434 static void gpiod_set_array_value_priv(bool raw
, bool can_sleep
,
1435 unsigned int array_size
,
1436 struct gpio_desc
**desc_array
,
1441 while (i
< array_size
) {
1442 struct gpio_chip
*chip
= desc_array
[i
]->chip
;
1443 unsigned long mask
[BITS_TO_LONGS(chip
->ngpio
)];
1444 unsigned long bits
[BITS_TO_LONGS(chip
->ngpio
)];
1448 WARN_ON(chip
->can_sleep
);
1450 memset(mask
, 0, sizeof(mask
));
1452 struct gpio_desc
*desc
= desc_array
[i
];
1453 int hwgpio
= gpio_chip_hwgpio(desc
);
1454 int value
= value_array
[i
];
1456 if (!raw
&& test_bit(FLAG_ACTIVE_LOW
, &desc
->flags
))
1458 trace_gpio_value(desc_to_gpio(desc
), 0, value
);
1460 * collect all normal outputs belonging to the same chip
1461 * open drain and open source outputs are set individually
1463 if (test_bit(FLAG_OPEN_DRAIN
, &desc
->flags
)) {
1464 _gpio_set_open_drain_value(desc
, value
);
1465 } else if (test_bit(FLAG_OPEN_SOURCE
, &desc
->flags
)) {
1466 _gpio_set_open_source_value(desc
, value
);
1468 __set_bit(hwgpio
, mask
);
1470 __set_bit(hwgpio
, bits
);
1472 __clear_bit(hwgpio
, bits
);
1476 } while ((i
< array_size
) && (desc_array
[i
]->chip
== chip
));
1477 /* push collected bits to outputs */
1479 gpio_chip_set_multiple(chip
, mask
, bits
);
1484 * gpiod_set_raw_value() - assign a gpio's raw value
1485 * @desc: gpio whose value will be assigned
1486 * @value: value to assign
1488 * Set the raw value of the GPIO, i.e. the value of its physical line without
1489 * regard for its ACTIVE_LOW status.
1491 * This function should be called from contexts where we cannot sleep, and will
1492 * complain if the GPIO chip functions potentially sleep.
1494 void gpiod_set_raw_value(struct gpio_desc
*desc
, int value
)
1498 /* Should be using gpio_set_value_cansleep() */
1499 WARN_ON(desc
->chip
->can_sleep
);
1500 _gpiod_set_raw_value(desc
, value
);
1502 EXPORT_SYMBOL_GPL(gpiod_set_raw_value
);
1505 * gpiod_set_value() - assign a gpio's value
1506 * @desc: gpio whose value will be assigned
1507 * @value: value to assign
1509 * Set the logical value of the GPIO, i.e. taking its ACTIVE_LOW status into
1512 * This function should be called from contexts where we cannot sleep, and will
1513 * complain if the GPIO chip functions potentially sleep.
1515 void gpiod_set_value(struct gpio_desc
*desc
, int value
)
1519 /* Should be using gpio_set_value_cansleep() */
1520 WARN_ON(desc
->chip
->can_sleep
);
1521 if (test_bit(FLAG_ACTIVE_LOW
, &desc
->flags
))
1523 _gpiod_set_raw_value(desc
, value
);
1525 EXPORT_SYMBOL_GPL(gpiod_set_value
);
1528 * gpiod_set_raw_array_value() - assign values to an array of GPIOs
1529 * @array_size: number of elements in the descriptor / value arrays
1530 * @desc_array: array of GPIO descriptors whose values will be assigned
1531 * @value_array: array of values to assign
1533 * Set the raw values of the GPIOs, i.e. the values of the physical lines
1534 * without regard for their ACTIVE_LOW status.
1536 * This function should be called from contexts where we cannot sleep, and will
1537 * complain if the GPIO chip functions potentially sleep.
1539 void gpiod_set_raw_array_value(unsigned int array_size
,
1540 struct gpio_desc
**desc_array
, int *value_array
)
1544 gpiod_set_array_value_priv(true, false, array_size
, desc_array
,
1547 EXPORT_SYMBOL_GPL(gpiod_set_raw_array_value
);
1550 * gpiod_set_array_value() - assign values to an array of GPIOs
1551 * @array_size: number of elements in the descriptor / value arrays
1552 * @desc_array: array of GPIO descriptors whose values will be assigned
1553 * @value_array: array of values to assign
1555 * Set the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status
1558 * This function should be called from contexts where we cannot sleep, and will
1559 * complain if the GPIO chip functions potentially sleep.
1561 void gpiod_set_array_value(unsigned int array_size
,
1562 struct gpio_desc
**desc_array
, int *value_array
)
1566 gpiod_set_array_value_priv(false, false, array_size
, desc_array
,
1569 EXPORT_SYMBOL_GPL(gpiod_set_array_value
);
1572 * gpiod_cansleep() - report whether gpio value access may sleep
1573 * @desc: gpio to check
1576 int gpiod_cansleep(const struct gpio_desc
*desc
)
1580 return desc
->chip
->can_sleep
;
1582 EXPORT_SYMBOL_GPL(gpiod_cansleep
);
1585 * gpiod_to_irq() - return the IRQ corresponding to a GPIO
1586 * @desc: gpio whose IRQ will be returned (already requested)
1588 * Return the IRQ corresponding to the passed GPIO, or an error code in case of
1591 int gpiod_to_irq(const struct gpio_desc
*desc
)
1593 struct gpio_chip
*chip
;
1599 offset
= gpio_chip_hwgpio(desc
);
1600 return chip
->to_irq
? chip
->to_irq(chip
, offset
) : -ENXIO
;
1602 EXPORT_SYMBOL_GPL(gpiod_to_irq
);
1605 * gpiochip_lock_as_irq() - lock a GPIO to be used as IRQ
1606 * @chip: the chip the GPIO to lock belongs to
1607 * @offset: the offset of the GPIO to lock as IRQ
1609 * This is used directly by GPIO drivers that want to lock down
1610 * a certain GPIO line to be used for IRQs.
1612 int gpiochip_lock_as_irq(struct gpio_chip
*chip
, unsigned int offset
)
1614 if (offset
>= chip
->ngpio
)
1617 if (test_bit(FLAG_IS_OUT
, &chip
->desc
[offset
].flags
)) {
1619 "%s: tried to flag a GPIO set as output for IRQ\n",
1624 set_bit(FLAG_USED_AS_IRQ
, &chip
->desc
[offset
].flags
);
1627 EXPORT_SYMBOL_GPL(gpiochip_lock_as_irq
);
1630 * gpiochip_unlock_as_irq() - unlock a GPIO used as IRQ
1631 * @chip: the chip the GPIO to lock belongs to
1632 * @offset: the offset of the GPIO to lock as IRQ
1634 * This is used directly by GPIO drivers that want to indicate
1635 * that a certain GPIO is no longer used exclusively for IRQ.
1637 void gpiochip_unlock_as_irq(struct gpio_chip
*chip
, unsigned int offset
)
1639 if (offset
>= chip
->ngpio
)
1642 clear_bit(FLAG_USED_AS_IRQ
, &chip
->desc
[offset
].flags
);
1644 EXPORT_SYMBOL_GPL(gpiochip_unlock_as_irq
);
1647 * gpiod_get_raw_value_cansleep() - return a gpio's raw value
1648 * @desc: gpio whose value will be returned
1650 * Return the GPIO's raw value, i.e. the value of the physical line disregarding
1651 * its ACTIVE_LOW status, or negative errno on failure.
1653 * This function is to be called from contexts that can sleep.
1655 int gpiod_get_raw_value_cansleep(const struct gpio_desc
*desc
)
1657 might_sleep_if(extra_checks
);
1660 return _gpiod_get_raw_value(desc
);
1662 EXPORT_SYMBOL_GPL(gpiod_get_raw_value_cansleep
);
1665 * gpiod_get_value_cansleep() - return a gpio's value
1666 * @desc: gpio whose value will be returned
1668 * Return the GPIO's logical value, i.e. taking the ACTIVE_LOW status into
1669 * account, or negative errno on failure.
1671 * This function is to be called from contexts that can sleep.
1673 int gpiod_get_value_cansleep(const struct gpio_desc
*desc
)
1677 might_sleep_if(extra_checks
);
1681 value
= _gpiod_get_raw_value(desc
);
1685 if (test_bit(FLAG_ACTIVE_LOW
, &desc
->flags
))
1690 EXPORT_SYMBOL_GPL(gpiod_get_value_cansleep
);
1693 * gpiod_set_raw_value_cansleep() - assign a gpio's raw value
1694 * @desc: gpio whose value will be assigned
1695 * @value: value to assign
1697 * Set the raw value of the GPIO, i.e. the value of its physical line without
1698 * regard for its ACTIVE_LOW status.
1700 * This function is to be called from contexts that can sleep.
1702 void gpiod_set_raw_value_cansleep(struct gpio_desc
*desc
, int value
)
1704 might_sleep_if(extra_checks
);
1707 _gpiod_set_raw_value(desc
, value
);
1709 EXPORT_SYMBOL_GPL(gpiod_set_raw_value_cansleep
);
1712 * gpiod_set_value_cansleep() - assign a gpio's value
1713 * @desc: gpio whose value will be assigned
1714 * @value: value to assign
1716 * Set the logical value of the GPIO, i.e. taking its ACTIVE_LOW status into
1719 * This function is to be called from contexts that can sleep.
1721 void gpiod_set_value_cansleep(struct gpio_desc
*desc
, int value
)
1723 might_sleep_if(extra_checks
);
1727 if (test_bit(FLAG_ACTIVE_LOW
, &desc
->flags
))
1729 _gpiod_set_raw_value(desc
, value
);
1731 EXPORT_SYMBOL_GPL(gpiod_set_value_cansleep
);
1734 * gpiod_set_raw_array_value_cansleep() - assign values to an array of GPIOs
1735 * @array_size: number of elements in the descriptor / value arrays
1736 * @desc_array: array of GPIO descriptors whose values will be assigned
1737 * @value_array: array of values to assign
1739 * Set the raw values of the GPIOs, i.e. the values of the physical lines
1740 * without regard for their ACTIVE_LOW status.
1742 * This function is to be called from contexts that can sleep.
1744 void gpiod_set_raw_array_value_cansleep(unsigned int array_size
,
1745 struct gpio_desc
**desc_array
,
1748 might_sleep_if(extra_checks
);
1751 gpiod_set_array_value_priv(true, true, array_size
, desc_array
,
1754 EXPORT_SYMBOL_GPL(gpiod_set_raw_array_value_cansleep
);
1757 * gpiod_set_array_value_cansleep() - assign values to an array of GPIOs
1758 * @array_size: number of elements in the descriptor / value arrays
1759 * @desc_array: array of GPIO descriptors whose values will be assigned
1760 * @value_array: array of values to assign
1762 * Set the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status
1765 * This function is to be called from contexts that can sleep.
1767 void gpiod_set_array_value_cansleep(unsigned int array_size
,
1768 struct gpio_desc
**desc_array
,
1771 might_sleep_if(extra_checks
);
1774 gpiod_set_array_value_priv(false, true, array_size
, desc_array
,
1777 EXPORT_SYMBOL_GPL(gpiod_set_array_value_cansleep
);
1780 * gpiod_add_lookup_table() - register GPIO device consumers
1781 * @table: table of consumers to register
1783 void gpiod_add_lookup_table(struct gpiod_lookup_table
*table
)
1785 mutex_lock(&gpio_lookup_lock
);
1787 list_add_tail(&table
->list
, &gpio_lookup_list
);
1789 mutex_unlock(&gpio_lookup_lock
);
1793 * gpiod_remove_lookup_table() - unregister GPIO device consumers
1794 * @table: table of consumers to unregister
1796 void gpiod_remove_lookup_table(struct gpiod_lookup_table
*table
)
1798 mutex_lock(&gpio_lookup_lock
);
1800 list_del(&table
->list
);
1802 mutex_unlock(&gpio_lookup_lock
);
1805 static struct gpio_desc
*of_find_gpio(struct device
*dev
, const char *con_id
,
1807 enum gpio_lookup_flags
*flags
)
1809 char prop_name
[32]; /* 32 is max size of property name */
1810 enum of_gpio_flags of_flags
;
1811 struct gpio_desc
*desc
;
1814 for (i
= 0; i
< ARRAY_SIZE(gpio_suffixes
); i
++) {
1816 snprintf(prop_name
, sizeof(prop_name
), "%s-%s", con_id
,
1819 snprintf(prop_name
, sizeof(prop_name
), "%s",
1822 desc
= of_get_named_gpiod_flags(dev
->of_node
, prop_name
, idx
,
1824 if (!IS_ERR(desc
) || (PTR_ERR(desc
) == -EPROBE_DEFER
))
1831 if (of_flags
& OF_GPIO_ACTIVE_LOW
)
1832 *flags
|= GPIO_ACTIVE_LOW
;
1834 if (of_flags
& OF_GPIO_SINGLE_ENDED
) {
1835 if (of_flags
& OF_GPIO_ACTIVE_LOW
)
1836 *flags
|= GPIO_OPEN_DRAIN
;
1838 *flags
|= GPIO_OPEN_SOURCE
;
1844 static struct gpio_desc
*acpi_find_gpio(struct device
*dev
, const char *con_id
,
1846 enum gpio_lookup_flags
*flags
)
1848 struct acpi_device
*adev
= ACPI_COMPANION(dev
);
1849 struct acpi_gpio_info info
;
1850 struct gpio_desc
*desc
;
1854 /* Try first from _DSD */
1855 for (i
= 0; i
< ARRAY_SIZE(gpio_suffixes
); i
++) {
1856 if (con_id
&& strcmp(con_id
, "gpios")) {
1857 snprintf(propname
, sizeof(propname
), "%s-%s",
1858 con_id
, gpio_suffixes
[i
]);
1860 snprintf(propname
, sizeof(propname
), "%s",
1864 desc
= acpi_get_gpiod_by_index(adev
, propname
, idx
, &info
);
1865 if (!IS_ERR(desc
) || (PTR_ERR(desc
) == -EPROBE_DEFER
))
1869 /* Then from plain _CRS GPIOs */
1871 desc
= acpi_get_gpiod_by_index(adev
, NULL
, idx
, &info
);
1876 if (info
.active_low
)
1877 *flags
|= GPIO_ACTIVE_LOW
;
1882 static struct gpiod_lookup_table
*gpiod_find_lookup_table(struct device
*dev
)
1884 const char *dev_id
= dev
? dev_name(dev
) : NULL
;
1885 struct gpiod_lookup_table
*table
;
1887 mutex_lock(&gpio_lookup_lock
);
1889 list_for_each_entry(table
, &gpio_lookup_list
, list
) {
1890 if (table
->dev_id
&& dev_id
) {
1892 * Valid strings on both ends, must be identical to have
1895 if (!strcmp(table
->dev_id
, dev_id
))
1899 * One of the pointers is NULL, so both must be to have
1902 if (dev_id
== table
->dev_id
)
1909 mutex_unlock(&gpio_lookup_lock
);
1913 static struct gpio_desc
*gpiod_find(struct device
*dev
, const char *con_id
,
1915 enum gpio_lookup_flags
*flags
)
1917 struct gpio_desc
*desc
= ERR_PTR(-ENOENT
);
1918 struct gpiod_lookup_table
*table
;
1919 struct gpiod_lookup
*p
;
1921 table
= gpiod_find_lookup_table(dev
);
1925 for (p
= &table
->table
[0]; p
->chip_label
; p
++) {
1926 struct gpio_chip
*chip
;
1928 /* idx must always match exactly */
1932 /* If the lookup entry has a con_id, require exact match */
1933 if (p
->con_id
&& (!con_id
|| strcmp(p
->con_id
, con_id
)))
1936 chip
= find_chip_by_name(p
->chip_label
);
1939 dev_err(dev
, "cannot find GPIO chip %s\n",
1941 return ERR_PTR(-ENODEV
);
1944 if (chip
->ngpio
<= p
->chip_hwnum
) {
1946 "requested GPIO %d is out of range [0..%d] for chip %s\n",
1947 idx
, chip
->ngpio
, chip
->label
);
1948 return ERR_PTR(-EINVAL
);
1951 desc
= gpiochip_get_desc(chip
, p
->chip_hwnum
);
1960 static int dt_gpio_count(struct device
*dev
, const char *con_id
)
1966 for (i
= 0; i
< ARRAY_SIZE(gpio_suffixes
); i
++) {
1968 snprintf(propname
, sizeof(propname
), "%s-%s",
1969 con_id
, gpio_suffixes
[i
]);
1971 snprintf(propname
, sizeof(propname
), "%s",
1974 ret
= of_gpio_named_count(dev
->of_node
, propname
);
1981 static int platform_gpio_count(struct device
*dev
, const char *con_id
)
1983 struct gpiod_lookup_table
*table
;
1984 struct gpiod_lookup
*p
;
1985 unsigned int count
= 0;
1987 table
= gpiod_find_lookup_table(dev
);
1991 for (p
= &table
->table
[0]; p
->chip_label
; p
++) {
1992 if ((con_id
&& p
->con_id
&& !strcmp(con_id
, p
->con_id
)) ||
1993 (!con_id
&& !p
->con_id
))
2003 * gpiod_count - return the number of GPIOs associated with a device / function
2004 * or -ENOENT if no GPIO has been assigned to the requested function
2005 * @dev: GPIO consumer, can be NULL for system-global GPIOs
2006 * @con_id: function within the GPIO consumer
2008 int gpiod_count(struct device
*dev
, const char *con_id
)
2010 int count
= -ENOENT
;
2012 if (IS_ENABLED(CONFIG_OF
) && dev
&& dev
->of_node
)
2013 count
= dt_gpio_count(dev
, con_id
);
2014 else if (IS_ENABLED(CONFIG_ACPI
) && dev
&& ACPI_HANDLE(dev
))
2015 count
= acpi_gpio_count(dev
, con_id
);
2018 count
= platform_gpio_count(dev
, con_id
);
2022 EXPORT_SYMBOL_GPL(gpiod_count
);
2025 * gpiod_get - obtain a GPIO for a given GPIO function
2026 * @dev: GPIO consumer, can be NULL for system-global GPIOs
2027 * @con_id: function within the GPIO consumer
2028 * @flags: optional GPIO initialization flags
2030 * Return the GPIO descriptor corresponding to the function con_id of device
2031 * dev, -ENOENT if no GPIO has been assigned to the requested function, or
2032 * another IS_ERR() code if an error occurred while trying to acquire the GPIO.
2034 struct gpio_desc
*__must_check
gpiod_get(struct device
*dev
, const char *con_id
,
2035 enum gpiod_flags flags
)
2037 return gpiod_get_index(dev
, con_id
, 0, flags
);
2039 EXPORT_SYMBOL_GPL(gpiod_get
);
2042 * gpiod_get_optional - obtain an optional GPIO for a given GPIO function
2043 * @dev: GPIO consumer, can be NULL for system-global GPIOs
2044 * @con_id: function within the GPIO consumer
2045 * @flags: optional GPIO initialization flags
2047 * This is equivalent to gpiod_get(), except that when no GPIO was assigned to
2048 * the requested function it will return NULL. This is convenient for drivers
2049 * that need to handle optional GPIOs.
2051 struct gpio_desc
*__must_check
gpiod_get_optional(struct device
*dev
,
2053 enum gpiod_flags flags
)
2055 return gpiod_get_index_optional(dev
, con_id
, 0, flags
);
2057 EXPORT_SYMBOL_GPL(gpiod_get_optional
);
2060 * gpiod_parse_flags - helper function to parse GPIO lookup flags
2061 * @desc: gpio to be setup
2062 * @lflags: gpio_lookup_flags - returned from of_find_gpio() or
2065 * Set the GPIO descriptor flags based on the given GPIO lookup flags.
2067 static void gpiod_parse_flags(struct gpio_desc
*desc
, unsigned long lflags
)
2069 if (lflags
& GPIO_ACTIVE_LOW
)
2070 set_bit(FLAG_ACTIVE_LOW
, &desc
->flags
);
2071 if (lflags
& GPIO_OPEN_DRAIN
)
2072 set_bit(FLAG_OPEN_DRAIN
, &desc
->flags
);
2073 if (lflags
& GPIO_OPEN_SOURCE
)
2074 set_bit(FLAG_OPEN_SOURCE
, &desc
->flags
);
2078 * gpiod_configure_flags - helper function to configure a given GPIO
2079 * @desc: gpio whose value will be assigned
2080 * @con_id: function within the GPIO consumer
2081 * @dflags: gpiod_flags - optional GPIO initialization flags
2083 * Return 0 on success, -ENOENT if no GPIO has been assigned to the
2084 * requested function and/or index, or another IS_ERR() code if an error
2085 * occurred while trying to acquire the GPIO.
2087 static int gpiod_configure_flags(struct gpio_desc
*desc
, const char *con_id
,
2088 enum gpiod_flags dflags
)
2092 /* No particular flag request, return here... */
2093 if (!(dflags
& GPIOD_FLAGS_BIT_DIR_SET
)) {
2094 pr_debug("no flags found for %s\n", con_id
);
2099 if (dflags
& GPIOD_FLAGS_BIT_DIR_OUT
)
2100 status
= gpiod_direction_output(desc
,
2101 dflags
& GPIOD_FLAGS_BIT_DIR_VAL
);
2103 status
= gpiod_direction_input(desc
);
2109 * gpiod_get_index - obtain a GPIO from a multi-index GPIO function
2110 * @dev: GPIO consumer, can be NULL for system-global GPIOs
2111 * @con_id: function within the GPIO consumer
2112 * @idx: index of the GPIO to obtain in the consumer
2113 * @flags: optional GPIO initialization flags
2115 * This variant of gpiod_get() allows to access GPIOs other than the first
2116 * defined one for functions that define several GPIOs.
2118 * Return a valid GPIO descriptor, -ENOENT if no GPIO has been assigned to the
2119 * requested function and/or index, or another IS_ERR() code if an error
2120 * occurred while trying to acquire the GPIO.
2122 struct gpio_desc
*__must_check
gpiod_get_index(struct device
*dev
,
2125 enum gpiod_flags flags
)
2127 struct gpio_desc
*desc
= NULL
;
2129 enum gpio_lookup_flags lookupflags
= 0;
2131 dev_dbg(dev
, "GPIO lookup for consumer %s\n", con_id
);
2134 /* Using device tree? */
2135 if (IS_ENABLED(CONFIG_OF
) && dev
->of_node
) {
2136 dev_dbg(dev
, "using device tree for GPIO lookup\n");
2137 desc
= of_find_gpio(dev
, con_id
, idx
, &lookupflags
);
2138 } else if (ACPI_COMPANION(dev
)) {
2139 dev_dbg(dev
, "using ACPI for GPIO lookup\n");
2140 desc
= acpi_find_gpio(dev
, con_id
, idx
, &lookupflags
);
2145 * Either we are not using DT or ACPI, or their lookup did not return
2146 * a result. In that case, use platform lookup as a fallback.
2148 if (!desc
|| desc
== ERR_PTR(-ENOENT
)) {
2149 dev_dbg(dev
, "using lookup tables for GPIO lookup\n");
2150 desc
= gpiod_find(dev
, con_id
, idx
, &lookupflags
);
2154 dev_dbg(dev
, "lookup for GPIO %s failed\n", con_id
);
2158 gpiod_parse_flags(desc
, lookupflags
);
2160 status
= gpiod_request(desc
, con_id
);
2162 return ERR_PTR(status
);
2164 status
= gpiod_configure_flags(desc
, con_id
, flags
);
2166 dev_dbg(dev
, "setup of GPIO %s failed\n", con_id
);
2168 return ERR_PTR(status
);
2173 EXPORT_SYMBOL_GPL(gpiod_get_index
);
2176 * fwnode_get_named_gpiod - obtain a GPIO from firmware node
2177 * @fwnode: handle of the firmware node
2178 * @propname: name of the firmware property representing the GPIO
2180 * This function can be used for drivers that get their configuration
2183 * Function properly finds the corresponding GPIO using whatever is the
2184 * underlying firmware interface and then makes sure that the GPIO
2185 * descriptor is requested before it is returned to the caller.
2187 * In case of error an ERR_PTR() is returned.
2189 struct gpio_desc
*fwnode_get_named_gpiod(struct fwnode_handle
*fwnode
,
2190 const char *propname
)
2192 struct gpio_desc
*desc
= ERR_PTR(-ENODEV
);
2193 bool active_low
= false;
2194 bool single_ended
= false;
2198 return ERR_PTR(-EINVAL
);
2200 if (is_of_node(fwnode
)) {
2201 enum of_gpio_flags flags
;
2203 desc
= of_get_named_gpiod_flags(to_of_node(fwnode
), propname
, 0,
2205 if (!IS_ERR(desc
)) {
2206 active_low
= flags
& OF_GPIO_ACTIVE_LOW
;
2207 single_ended
= flags
& OF_GPIO_SINGLE_ENDED
;
2209 } else if (is_acpi_node(fwnode
)) {
2210 struct acpi_gpio_info info
;
2212 desc
= acpi_node_get_gpiod(fwnode
, propname
, 0, &info
);
2214 active_low
= info
.active_low
;
2221 set_bit(FLAG_ACTIVE_LOW
, &desc
->flags
);
2225 set_bit(FLAG_OPEN_DRAIN
, &desc
->flags
);
2227 set_bit(FLAG_OPEN_SOURCE
, &desc
->flags
);
2230 ret
= gpiod_request(desc
, NULL
);
2232 return ERR_PTR(ret
);
2236 EXPORT_SYMBOL_GPL(fwnode_get_named_gpiod
);
2239 * gpiod_get_index_optional - obtain an optional GPIO from a multi-index GPIO
2241 * @dev: GPIO consumer, can be NULL for system-global GPIOs
2242 * @con_id: function within the GPIO consumer
2243 * @index: index of the GPIO to obtain in the consumer
2244 * @flags: optional GPIO initialization flags
2246 * This is equivalent to gpiod_get_index(), except that when no GPIO with the
2247 * specified index was assigned to the requested function it will return NULL.
2248 * This is convenient for drivers that need to handle optional GPIOs.
2250 struct gpio_desc
*__must_check
gpiod_get_index_optional(struct device
*dev
,
2253 enum gpiod_flags flags
)
2255 struct gpio_desc
*desc
;
2257 desc
= gpiod_get_index(dev
, con_id
, index
, flags
);
2259 if (PTR_ERR(desc
) == -ENOENT
)
2265 EXPORT_SYMBOL_GPL(gpiod_get_index_optional
);
2268 * gpiod_hog - Hog the specified GPIO desc given the provided flags
2269 * @desc: gpio whose value will be assigned
2270 * @name: gpio line name
2271 * @lflags: gpio_lookup_flags - returned from of_find_gpio() or
2273 * @dflags: gpiod_flags - optional GPIO initialization flags
2275 int gpiod_hog(struct gpio_desc
*desc
, const char *name
,
2276 unsigned long lflags
, enum gpiod_flags dflags
)
2278 struct gpio_chip
*chip
;
2279 struct gpio_desc
*local_desc
;
2283 chip
= gpiod_to_chip(desc
);
2284 hwnum
= gpio_chip_hwgpio(desc
);
2286 gpiod_parse_flags(desc
, lflags
);
2288 local_desc
= gpiochip_request_own_desc(chip
, hwnum
, name
);
2289 if (IS_ERR(local_desc
)) {
2290 pr_err("requesting hog GPIO %s (chip %s, offset %d) failed\n",
2291 name
, chip
->label
, hwnum
);
2292 return PTR_ERR(local_desc
);
2295 status
= gpiod_configure_flags(desc
, name
, dflags
);
2297 pr_err("setup of hog GPIO %s (chip %s, offset %d) failed\n",
2298 name
, chip
->label
, hwnum
);
2299 gpiochip_free_own_desc(desc
);
2303 /* Mark GPIO as hogged so it can be identified and removed later */
2304 set_bit(FLAG_IS_HOGGED
, &desc
->flags
);
2306 pr_info("GPIO line %d (%s) hogged as %s%s\n",
2307 desc_to_gpio(desc
), name
,
2308 (dflags
&GPIOD_FLAGS_BIT_DIR_OUT
) ? "output" : "input",
2309 (dflags
&GPIOD_FLAGS_BIT_DIR_OUT
) ?
2310 (dflags
&GPIOD_FLAGS_BIT_DIR_VAL
) ? "/high" : "/low":"");
2316 * gpiochip_free_hogs - Scan gpio-controller chip and release GPIO hog
2317 * @chip: gpio chip to act on
2319 * This is only used by of_gpiochip_remove to free hogged gpios
2321 static void gpiochip_free_hogs(struct gpio_chip
*chip
)
2325 for (id
= 0; id
< chip
->ngpio
; id
++) {
2326 if (test_bit(FLAG_IS_HOGGED
, &chip
->desc
[id
].flags
))
2327 gpiochip_free_own_desc(&chip
->desc
[id
]);
2332 * gpiod_get_array - obtain multiple GPIOs from a multi-index GPIO function
2333 * @dev: GPIO consumer, can be NULL for system-global GPIOs
2334 * @con_id: function within the GPIO consumer
2335 * @flags: optional GPIO initialization flags
2337 * This function acquires all the GPIOs defined under a given function.
2339 * Return a struct gpio_descs containing an array of descriptors, -ENOENT if
2340 * no GPIO has been assigned to the requested function, or another IS_ERR()
2341 * code if an error occurred while trying to acquire the GPIOs.
2343 struct gpio_descs
*__must_check
gpiod_get_array(struct device
*dev
,
2345 enum gpiod_flags flags
)
2347 struct gpio_desc
*desc
;
2348 struct gpio_descs
*descs
;
2351 count
= gpiod_count(dev
, con_id
);
2353 return ERR_PTR(count
);
2355 descs
= kzalloc(sizeof(*descs
) + sizeof(descs
->desc
[0]) * count
,
2358 return ERR_PTR(-ENOMEM
);
2360 for (descs
->ndescs
= 0; descs
->ndescs
< count
; ) {
2361 desc
= gpiod_get_index(dev
, con_id
, descs
->ndescs
, flags
);
2363 gpiod_put_array(descs
);
2364 return ERR_CAST(desc
);
2366 descs
->desc
[descs
->ndescs
] = desc
;
2371 EXPORT_SYMBOL_GPL(gpiod_get_array
);
2374 * gpiod_get_array_optional - obtain multiple GPIOs from a multi-index GPIO
2376 * @dev: GPIO consumer, can be NULL for system-global GPIOs
2377 * @con_id: function within the GPIO consumer
2378 * @flags: optional GPIO initialization flags
2380 * This is equivalent to gpiod_get_array(), except that when no GPIO was
2381 * assigned to the requested function it will return NULL.
2383 struct gpio_descs
*__must_check
gpiod_get_array_optional(struct device
*dev
,
2385 enum gpiod_flags flags
)
2387 struct gpio_descs
*descs
;
2389 descs
= gpiod_get_array(dev
, con_id
, flags
);
2390 if (IS_ERR(descs
) && (PTR_ERR(descs
) == -ENOENT
))
2395 EXPORT_SYMBOL_GPL(gpiod_get_array_optional
);
2398 * gpiod_put - dispose of a GPIO descriptor
2399 * @desc: GPIO descriptor to dispose of
2401 * No descriptor can be used after gpiod_put() has been called on it.
2403 void gpiod_put(struct gpio_desc
*desc
)
2407 EXPORT_SYMBOL_GPL(gpiod_put
);
2410 * gpiod_put_array - dispose of multiple GPIO descriptors
2411 * @descs: struct gpio_descs containing an array of descriptors
2413 void gpiod_put_array(struct gpio_descs
*descs
)
2417 for (i
= 0; i
< descs
->ndescs
; i
++)
2418 gpiod_put(descs
->desc
[i
]);
2422 EXPORT_SYMBOL_GPL(gpiod_put_array
);
2424 #ifdef CONFIG_DEBUG_FS
2426 static void gpiolib_dbg_show(struct seq_file
*s
, struct gpio_chip
*chip
)
2429 unsigned gpio
= chip
->base
;
2430 struct gpio_desc
*gdesc
= &chip
->desc
[0];
2434 for (i
= 0; i
< chip
->ngpio
; i
++, gpio
++, gdesc
++) {
2435 if (!test_bit(FLAG_REQUESTED
, &gdesc
->flags
)) {
2437 seq_printf(s
, " gpio-%-3d (%-20.20s)\n",
2443 gpiod_get_direction(gdesc
);
2444 is_out
= test_bit(FLAG_IS_OUT
, &gdesc
->flags
);
2445 is_irq
= test_bit(FLAG_USED_AS_IRQ
, &gdesc
->flags
);
2446 seq_printf(s
, " gpio-%-3d (%-20.20s|%-20.20s) %s %s %s",
2447 gpio
, gdesc
->name
? gdesc
->name
: "", gdesc
->label
,
2448 is_out
? "out" : "in ",
2450 ? (chip
->get(chip
, i
) ? "hi" : "lo")
2452 is_irq
? "IRQ" : " ");
2453 seq_printf(s
, "\n");
2457 static void *gpiolib_seq_start(struct seq_file
*s
, loff_t
*pos
)
2459 unsigned long flags
;
2460 struct gpio_chip
*chip
= NULL
;
2461 loff_t index
= *pos
;
2465 spin_lock_irqsave(&gpio_lock
, flags
);
2466 list_for_each_entry(chip
, &gpio_chips
, list
)
2468 spin_unlock_irqrestore(&gpio_lock
, flags
);
2471 spin_unlock_irqrestore(&gpio_lock
, flags
);
2476 static void *gpiolib_seq_next(struct seq_file
*s
, void *v
, loff_t
*pos
)
2478 unsigned long flags
;
2479 struct gpio_chip
*chip
= v
;
2482 spin_lock_irqsave(&gpio_lock
, flags
);
2483 if (list_is_last(&chip
->list
, &gpio_chips
))
2486 ret
= list_entry(chip
->list
.next
, struct gpio_chip
, list
);
2487 spin_unlock_irqrestore(&gpio_lock
, flags
);
2495 static void gpiolib_seq_stop(struct seq_file
*s
, void *v
)
2499 static int gpiolib_seq_show(struct seq_file
*s
, void *v
)
2501 struct gpio_chip
*chip
= v
;
2504 seq_printf(s
, "%sGPIOs %d-%d", (char *)s
->private,
2505 chip
->base
, chip
->base
+ chip
->ngpio
- 1);
2508 seq_printf(s
, ", %s/%s", dev
->bus
? dev
->bus
->name
: "no-bus",
2511 seq_printf(s
, ", %s", chip
->label
);
2512 if (chip
->can_sleep
)
2513 seq_printf(s
, ", can sleep");
2514 seq_printf(s
, ":\n");
2517 chip
->dbg_show(s
, chip
);
2519 gpiolib_dbg_show(s
, chip
);
2524 static const struct seq_operations gpiolib_seq_ops
= {
2525 .start
= gpiolib_seq_start
,
2526 .next
= gpiolib_seq_next
,
2527 .stop
= gpiolib_seq_stop
,
2528 .show
= gpiolib_seq_show
,
2531 static int gpiolib_open(struct inode
*inode
, struct file
*file
)
2533 return seq_open(file
, &gpiolib_seq_ops
);
2536 static const struct file_operations gpiolib_operations
= {
2537 .owner
= THIS_MODULE
,
2538 .open
= gpiolib_open
,
2540 .llseek
= seq_lseek
,
2541 .release
= seq_release
,
2544 static int __init
gpiolib_debugfs_init(void)
2546 /* /sys/kernel/debug/gpio */
2547 (void) debugfs_create_file("gpio", S_IFREG
| S_IRUGO
,
2548 NULL
, NULL
, &gpiolib_operations
);
2551 subsys_initcall(gpiolib_debugfs_init
);
2553 #endif /* DEBUG_FS */