xref: /linux-6.15/include/linux/gpio/machine.h (revision 228cd2db)
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 #include <linux/list.h>
7 
8 enum gpio_lookup_flags {
9 	GPIO_ACTIVE_HIGH = (0 << 0),
10 	GPIO_ACTIVE_LOW = (1 << 0),
11 	GPIO_OPEN_DRAIN = (1 << 1),
12 	GPIO_OPEN_SOURCE = (1 << 2),
13 	GPIO_PERSISTENT = (0 << 3),
14 	GPIO_TRANSITORY = (1 << 3),
15 	GPIO_PULL_UP = (1 << 4),
16 	GPIO_PULL_DOWN = (1 << 5),
17 };
18 
19 /**
20  * struct gpiod_lookup - lookup table
21  * @chip_label: name of the chip the GPIO belongs to
22  * @chip_hwnum: hardware number (i.e. relative to the chip) of the GPIO
23  * @con_id: name of the GPIO from the device's point of view
24  * @idx: index of the GPIO in case several GPIOs share the same name
25  * @flags: mask of GPIO_* values
26  *
27  * gpiod_lookup is a lookup table for associating GPIOs to specific devices and
28  * functions using platform data.
29  */
30 struct gpiod_lookup {
31 	const char *chip_label;
32 	u16 chip_hwnum;
33 	const char *con_id;
34 	unsigned int idx;
35 	enum gpio_lookup_flags flags;
36 };
37 
38 struct gpiod_lookup_table {
39 	struct list_head list;
40 	const char *dev_id;
41 	struct gpiod_lookup table[];
42 };
43 
44 /**
45  * struct gpiod_hog - GPIO line hog table
46  * @chip_label: name of the chip the GPIO belongs to
47  * @chip_hwnum: hardware number (i.e. relative to the chip) of the GPIO
48  * @line_name: consumer name for the hogged line
49  * @lflags: mask of GPIO lookup flags
50  * @dflags: GPIO flags used to specify the direction and value
51  */
52 struct gpiod_hog {
53 	struct list_head list;
54 	const char *chip_label;
55 	u16 chip_hwnum;
56 	const char *line_name;
57 	enum gpio_lookup_flags lflags;
58 	int dflags;
59 };
60 
61 /*
62  * Simple definition of a single GPIO under a con_id
63  */
64 #define GPIO_LOOKUP(_chip_label, _chip_hwnum, _con_id, _flags) \
65 	GPIO_LOOKUP_IDX(_chip_label, _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(_chip_label, _chip_hwnum, _con_id, _idx, _flags)  \
73 {                                                                         \
74 	.chip_label = _chip_label,                                        \
75 	.chip_hwnum = _chip_hwnum,                                        \
76 	.con_id = _con_id,                                                \
77 	.idx = _idx,                                                      \
78 	.flags = _flags,                                                  \
79 }
80 
81 /*
82  * Simple definition of a single GPIO hog in an array.
83  */
84 #define GPIO_HOG(_chip_label, _chip_hwnum, _line_name, _lflags, _dflags)  \
85 {                                                                         \
86 	.chip_label = _chip_label,                                        \
87 	.chip_hwnum = _chip_hwnum,                                        \
88 	.line_name = _line_name,                                          \
89 	.lflags = _lflags,                                                \
90 	.dflags = _dflags,                                                \
91 }
92 
93 #ifdef CONFIG_GPIOLIB
94 void gpiod_add_lookup_table(struct gpiod_lookup_table *table);
95 void gpiod_add_lookup_tables(struct gpiod_lookup_table **tables, size_t n);
96 void gpiod_remove_lookup_table(struct gpiod_lookup_table *table);
97 void gpiod_add_hogs(struct gpiod_hog *hogs);
98 #else
99 static inline
100 void gpiod_add_lookup_table(struct gpiod_lookup_table *table) {}
101 static inline
102 void gpiod_add_lookup_tables(struct gpiod_lookup_table **tables, size_t n) {}
103 static inline
104 void gpiod_remove_lookup_table(struct gpiod_lookup_table *table) {}
105 static inline void gpiod_add_hogs(struct gpiod_hog *hogs) {}
106 #endif
107 
108 #endif /* __LINUX_GPIO_MACHINE_H */
109