]> git.proxmox.com Git - mirror_ubuntu-artful-kernel.git/blob - include/linux/of_gpio.h
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/livep...
[mirror_ubuntu-artful-kernel.git] / include / linux / of_gpio.h
1 /*
2 * OF helpers for the GPIO API
3 *
4 * Copyright (c) 2007-2008 MontaVista Software, Inc.
5 *
6 * Author: Anton Vorontsov <avorontsov@ru.mvista.com>
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License as published by
10 * the Free Software Foundation; either version 2 of the License, or
11 * (at your option) any later version.
12 */
13
14 #ifndef __LINUX_OF_GPIO_H
15 #define __LINUX_OF_GPIO_H
16
17 #include <linux/compiler.h>
18 #include <linux/kernel.h>
19 #include <linux/errno.h>
20 #include <linux/gpio.h>
21 #include <linux/of.h>
22
23 struct device_node;
24
25 /*
26 * This is Linux-specific flags. By default controllers' and Linux' mapping
27 * match, but GPIO controllers are free to translate their own flags to
28 * Linux-specific in their .xlate callback. Though, 1:1 mapping is recommended.
29 */
30 enum of_gpio_flags {
31 OF_GPIO_ACTIVE_LOW = 0x1,
32 OF_GPIO_SINGLE_ENDED = 0x2,
33 };
34
35 #ifdef CONFIG_OF_GPIO
36
37 /*
38 * OF GPIO chip for memory mapped banks
39 */
40 struct of_mm_gpio_chip {
41 struct gpio_chip gc;
42 void (*save_regs)(struct of_mm_gpio_chip *mm_gc);
43 void __iomem *regs;
44 };
45
46 static inline struct of_mm_gpio_chip *to_of_mm_gpio_chip(struct gpio_chip *gc)
47 {
48 return container_of(gc, struct of_mm_gpio_chip, gc);
49 }
50
51 extern int of_get_named_gpio_flags(struct device_node *np,
52 const char *list_name, int index, enum of_gpio_flags *flags);
53
54 extern int of_mm_gpiochip_add_data(struct device_node *np,
55 struct of_mm_gpio_chip *mm_gc,
56 void *data);
57 static inline int of_mm_gpiochip_add(struct device_node *np,
58 struct of_mm_gpio_chip *mm_gc)
59 {
60 return of_mm_gpiochip_add_data(np, mm_gc, NULL);
61 }
62 extern void of_mm_gpiochip_remove(struct of_mm_gpio_chip *mm_gc);
63
64 extern int of_gpiochip_add(struct gpio_chip *gc);
65 extern void of_gpiochip_remove(struct gpio_chip *gc);
66 extern int of_gpio_simple_xlate(struct gpio_chip *gc,
67 const struct of_phandle_args *gpiospec,
68 u32 *flags);
69
70 #else /* CONFIG_OF_GPIO */
71
72 /* Drivers may not strictly depend on the GPIO support, so let them link. */
73 static inline int of_get_named_gpio_flags(struct device_node *np,
74 const char *list_name, int index, enum of_gpio_flags *flags)
75 {
76 if (flags)
77 *flags = 0;
78
79 return -ENOSYS;
80 }
81
82 static inline int of_gpio_simple_xlate(struct gpio_chip *gc,
83 const struct of_phandle_args *gpiospec,
84 u32 *flags)
85 {
86 return -ENOSYS;
87 }
88
89 static inline int of_gpiochip_add(struct gpio_chip *gc) { return 0; }
90 static inline void of_gpiochip_remove(struct gpio_chip *gc) { }
91
92 #endif /* CONFIG_OF_GPIO */
93
94 /**
95 * of_gpio_named_count() - Count GPIOs for a device
96 * @np: device node to count GPIOs for
97 * @propname: property name containing gpio specifier(s)
98 *
99 * The function returns the count of GPIOs specified for a node.
100 * Note that the empty GPIO specifiers count too. Returns either
101 * Number of gpios defined in property,
102 * -EINVAL for an incorrectly formed gpios property, or
103 * -ENOENT for a missing gpios property
104 *
105 * Example:
106 * gpios = <0
107 * &gpio1 1 2
108 * 0
109 * &gpio2 3 4>;
110 *
111 * The above example defines four GPIOs, two of which are not specified.
112 * This function will return '4'
113 */
114 static inline int of_gpio_named_count(struct device_node *np, const char* propname)
115 {
116 return of_count_phandle_with_args(np, propname, "#gpio-cells");
117 }
118
119 /**
120 * of_gpio_count() - Count GPIOs for a device
121 * @np: device node to count GPIOs for
122 *
123 * Same as of_gpio_named_count, but hard coded to use the 'gpios' property
124 */
125 static inline int of_gpio_count(struct device_node *np)
126 {
127 return of_gpio_named_count(np, "gpios");
128 }
129
130 static inline int of_get_gpio_flags(struct device_node *np, int index,
131 enum of_gpio_flags *flags)
132 {
133 return of_get_named_gpio_flags(np, "gpios", index, flags);
134 }
135
136 /**
137 * of_get_named_gpio() - Get a GPIO number to use with GPIO API
138 * @np: device node to get GPIO from
139 * @propname: Name of property containing gpio specifier(s)
140 * @index: index of the GPIO
141 *
142 * Returns GPIO number to use with Linux generic GPIO API, or one of the errno
143 * value on the error condition.
144 */
145 static inline int of_get_named_gpio(struct device_node *np,
146 const char *propname, int index)
147 {
148 return of_get_named_gpio_flags(np, propname, index, NULL);
149 }
150
151 /**
152 * of_get_gpio() - Get a GPIO number to use with GPIO API
153 * @np: device node to get GPIO from
154 * @index: index of the GPIO
155 *
156 * Returns GPIO number to use with Linux generic GPIO API, or one of the errno
157 * value on the error condition.
158 */
159 static inline int of_get_gpio(struct device_node *np, int index)
160 {
161 return of_get_gpio_flags(np, index, NULL);
162 }
163
164 #endif /* __LINUX_OF_GPIO_H */