Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef __LINUX_GPIO_MACHINE_H
3#define __LINUX_GPIO_MACHINE_H
4
5#include <linux/types.h>
6
7enum gpio_lookup_flags {
8 GPIO_ACTIVE_HIGH = (0 << 0),
9 GPIO_ACTIVE_LOW = (1 << 0),
10 GPIO_OPEN_DRAIN = (1 << 1),
11 GPIO_OPEN_SOURCE = (1 << 2),
12 GPIO_PERSISTENT = (0 << 3),
13 GPIO_TRANSITORY = (1 << 3),
14 GPIO_PULL_UP = (1 << 4),
15 GPIO_PULL_DOWN = (1 << 5),
16 GPIO_PULL_DISABLE = (1 << 6),
17
18 GPIO_LOOKUP_FLAGS_DEFAULT = GPIO_ACTIVE_HIGH | GPIO_PERSISTENT,
19};
20
21/**
22 * struct gpiod_lookup - lookup table
23 * @key: either the name of the chip the GPIO belongs to, or the GPIO line name
24 * Note that GPIO line names are not guaranteed to be globally unique,
25 * so this will use the first match found!
26 * @chip_hwnum: hardware number (i.e. relative to the chip) of the GPIO, or
27 * U16_MAX to indicate that @key is a GPIO line name
28 * @con_id: name of the GPIO from the device's point of view
29 * @idx: index of the GPIO in case several GPIOs share the same name
30 * @flags: bitmask of gpio_lookup_flags GPIO_* values
31 *
32 * gpiod_lookup is a lookup table for associating GPIOs to specific devices and
33 * functions using platform data.
34 */
35struct gpiod_lookup {
36 const char *key;
37 u16 chip_hwnum;
38 const char *con_id;
39 unsigned int idx;
40 unsigned long flags;
41};
42
43struct gpiod_lookup_table {
44 struct list_head list;
45 const char *dev_id;
46 struct gpiod_lookup table[];
47};
48
49/*
50 * Helper for lookup tables with just one single lookup for a device.
51 */
52#define GPIO_LOOKUP_SINGLE(_name, _dev_id, _key, _chip_hwnum, _con_id, _flags) \
53static struct gpiod_lookup_table _name = { \
54 .dev_id = _dev_id, \
55 .table = { \
56 GPIO_LOOKUP(_key, _chip_hwnum, _con_id, _flags), \
57 {}, \
58 }, \
59}
60
61/*
62 * Simple definition of a single GPIO under a con_id
63 */
64#define GPIO_LOOKUP(_key, _chip_hwnum, _con_id, _flags) \
65 GPIO_LOOKUP_IDX(_key, _chip_hwnum, _con_id, 0, _flags)
66
67/*
68 * Use this macro if you need to have several GPIOs under the same con_id.
69 * Each GPIO needs to use a different index and can be accessed using
70 * gpiod_get_index()
71 */
72#define GPIO_LOOKUP_IDX(_key, _chip_hwnum, _con_id, _idx, _flags) \
73(struct gpiod_lookup) { \
74 .key = _key, \
75 .chip_hwnum = _chip_hwnum, \
76 .con_id = _con_id, \
77 .idx = _idx, \
78 .flags = _flags, \
79}
80
81#ifdef CONFIG_GPIOLIB
82void gpiod_add_lookup_table(struct gpiod_lookup_table *table);
83void gpiod_add_lookup_tables(struct gpiod_lookup_table **tables, size_t n);
84void gpiod_remove_lookup_table(struct gpiod_lookup_table *table);
85#else /* ! CONFIG_GPIOLIB */
86static inline
87void gpiod_add_lookup_table(struct gpiod_lookup_table *table) {}
88static inline
89void gpiod_add_lookup_tables(struct gpiod_lookup_table **tables, size_t n) {}
90static inline
91void gpiod_remove_lookup_table(struct gpiod_lookup_table *table) {}
92#endif /* CONFIG_GPIOLIB */
93
94#endif /* __LINUX_GPIO_MACHINE_H */