1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
|
/* SPDX-License-Identifier: GPL-2.0-or-later */
/*
* OF helpers for the GPIO API
*
* based on Linux OF_GPIO API
*/
#ifndef __OF_GPIO_H
#define __OF_GPIO_H
/*
* This is Linux-specific flags. By default controllers' and Linux' mapping
* match, but GPIO controllers are free to translate their own flags to
* Linux-specific in their .xlate callback. Though, 1:1 mapping is recommended.
*/
enum of_gpio_flags {
OF_GPIO_ACTIVE_LOW = 0x1,
};
#ifdef CONFIG_OF_GPIO
extern int of_get_named_gpio_flags(struct device_node *np,
const char *list_name, int index, enum of_gpio_flags *flags);
#else /* CONFIG_OF_GPIO */
static inline int of_get_named_gpio_flags(struct device_node *np,
const char *list_name, int index, enum of_gpio_flags *flags)
{
return -ENOSYS;
}
#endif /* CONFIG_OF_GPIO */
/**
* of_gpio_named_count() - Count GPIOs for a device
* @np: device node to count GPIOs for
* @propname: property name containing gpio specifier(s)
*
* The function returns the count of GPIOs specified for a node.
* Note that the empty GPIO specifiers count too. Returns either
* Number of gpios defined in property,
* -EINVAL for an incorrectly formed gpios property, or
* -ENOENT for a missing gpios property
*
* Example:
* gpios = <0
* &gpio1 1 2
* 0
* &gpio2 3 4>;
*
* The above example defines four GPIOs, two of which are not specified.
* This function will return '4'
*/
static inline int of_gpio_named_count(struct device_node *np, const char* propname)
{
return of_count_phandle_with_args(np, propname, "#gpio-cells");
}
/**
* of_gpio_count() - Count GPIOs for a device
* @np: device node to count GPIOs for
*
* Same as of_gpio_named_count, but hard coded to use the 'gpios' property
*/
static inline int of_gpio_count(struct device_node *np)
{
return of_gpio_named_count(np, "gpios");
}
static inline int of_get_gpio_flags(struct device_node *np, int index,
enum of_gpio_flags *flags)
{
return of_get_named_gpio_flags(np, "gpios", index, flags);
}
static inline int of_get_named_gpio(struct device_node *np,
const char *list_name, int index)
{
return of_get_named_gpio_flags(np, list_name, index, NULL);
}
/**
* of_get_gpio() - Get a GPIO number to use with GPIO API
* @np: device node to get GPIO from
* @index: index of the GPIO
*
* Returns GPIO number to use with Linux generic GPIO API, or one of the errno
* value on the error condition.
*/
static inline int of_get_gpio(struct device_node *np, int index)
{
return of_get_gpio_flags(np, index, NULL);
}
#endif
|