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Anton Vorontsov863fbf42008-04-11 23:06:45 +10001/*
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
Anton Vorontsovb908b532008-12-01 06:30:04 +000017#include <linux/compiler.h>
18#include <linux/kernel.h>
Anton Vorontsov863fbf42008-04-11 23:06:45 +100019#include <linux/errno.h>
Wolfgang Grandegger18ad7a62008-05-30 22:51:33 +100020#include <linux/gpio.h>
Grant Likely15c9a0a2011-12-12 09:25:57 -070021#include <linux/of.h>
Stephen Rothwell335d7a7d2013-10-29 20:10:13 +110022#include <linux/gpio/consumer.h>
Anton Vorontsov863fbf42008-04-11 23:06:45 +100023
Anton Vorontsovb908b532008-12-01 06:30:04 +000024struct device_node;
25
26/*
27 * This is Linux-specific flags. By default controllers' and Linux' mapping
28 * match, but GPIO controllers are free to translate their own flags to
29 * Linux-specific in their .xlate callback. Though, 1:1 mapping is recommended.
30 */
31enum of_gpio_flags {
32 OF_GPIO_ACTIVE_LOW = 0x1,
33};
34
Anton Vorontsov863fbf42008-04-11 23:06:45 +100035#ifdef CONFIG_OF_GPIO
36
37/*
Anton Vorontsov863fbf42008-04-11 23:06:45 +100038 * OF GPIO chip for memory mapped banks
39 */
40struct of_mm_gpio_chip {
Anton Vorontsova19e3da2010-06-08 07:48:16 -060041 struct gpio_chip gc;
Anton Vorontsov863fbf42008-04-11 23:06:45 +100042 void (*save_regs)(struct of_mm_gpio_chip *mm_gc);
43 void __iomem *regs;
44};
45
46static inline struct of_mm_gpio_chip *to_of_mm_gpio_chip(struct gpio_chip *gc)
47{
Anton Vorontsova19e3da2010-06-08 07:48:16 -060048 return container_of(gc, struct of_mm_gpio_chip, gc);
Anton Vorontsov863fbf42008-04-11 23:06:45 +100049}
50
Alexandre Courbotaf8b6372013-10-17 10:21:37 -070051extern struct gpio_desc *of_get_named_gpiod_flags(struct device_node *np,
John Bonesioa6b09192011-06-27 16:49:57 -070052 const char *list_name, int index, enum of_gpio_flags *flags);
53
Anton Vorontsov863fbf42008-04-11 23:06:45 +100054extern int of_mm_gpiochip_add(struct device_node *np,
55 struct of_mm_gpio_chip *mm_gc);
Grant Likely594fa262010-06-08 07:48:16 -060056
Anton Vorontsov391c9702010-06-08 07:48:17 -060057extern void of_gpiochip_add(struct gpio_chip *gc);
58extern void of_gpiochip_remove(struct gpio_chip *gc);
Grant Likely15c9a0a2011-12-12 09:25:57 -070059extern int of_gpio_simple_xlate(struct gpio_chip *gc,
60 const struct of_phandle_args *gpiospec,
61 u32 *flags);
Grant Likely594fa262010-06-08 07:48:16 -060062
Anton Vorontsova19e3da2010-06-08 07:48:16 -060063#else /* CONFIG_OF_GPIO */
Anton Vorontsov863fbf42008-04-11 23:06:45 +100064
65/* Drivers may not strictly depend on the GPIO support, so let them link. */
Alexandre Courbotaf8b6372013-10-17 10:21:37 -070066static inline struct gpio_desc *of_get_named_gpiod_flags(struct device_node *np,
John Bonesioa6b09192011-06-27 16:49:57 -070067 const char *list_name, int index, enum of_gpio_flags *flags)
Anton Vorontsov863fbf42008-04-11 23:06:45 +100068{
Alexandre Courbotaf8b6372013-10-17 10:21:37 -070069 return ERR_PTR(-ENOSYS);
Anton Vorontsov863fbf42008-04-11 23:06:45 +100070}
71
Jamie Iles3038bbd2011-07-28 16:25:41 +010072static inline int of_gpio_simple_xlate(struct gpio_chip *gc,
Grant Likely15c9a0a2011-12-12 09:25:57 -070073 const struct of_phandle_args *gpiospec,
74 u32 *flags)
Jamie Iles3038bbd2011-07-28 16:25:41 +010075{
76 return -ENOSYS;
77}
78
Anton Vorontsov391c9702010-06-08 07:48:17 -060079static inline void of_gpiochip_add(struct gpio_chip *gc) { }
80static inline void of_gpiochip_remove(struct gpio_chip *gc) { }
81
Anton Vorontsov863fbf42008-04-11 23:06:45 +100082#endif /* CONFIG_OF_GPIO */
83
Alexandre Courbotaf8b6372013-10-17 10:21:37 -070084static inline int of_get_named_gpio_flags(struct device_node *np,
85 const char *list_name, int index, enum of_gpio_flags *flags)
86{
87 struct gpio_desc *desc;
88 desc = of_get_named_gpiod_flags(np, list_name, index, flags);
89
90 if (IS_ERR(desc))
91 return PTR_ERR(desc);
92 else
93 return desc_to_gpio(desc);
94}
95
Anton Vorontsovb908b532008-12-01 06:30:04 +000096/**
Grant Likelye80beb22013-02-12 17:48:37 +000097 * of_gpio_named_count() - Count GPIOs for a device
Jean-Christophe PLAGNIOL-VILLARDff64abe2012-02-02 16:20:01 +010098 * @np: device node to count GPIOs for
Grant Likelye80beb22013-02-12 17:48:37 +000099 * @propname: property name containing gpio specifier(s)
Jean-Christophe PLAGNIOL-VILLARDff64abe2012-02-02 16:20:01 +0100100 *
101 * The function returns the count of GPIOs specified for a node.
Grant Likelye80beb22013-02-12 17:48:37 +0000102 * Note that the empty GPIO specifiers count too. Returns either
103 * Number of gpios defined in property,
104 * -EINVAL for an incorrectly formed gpios property, or
105 * -ENOENT for a missing gpios property
Jean-Christophe PLAGNIOL-VILLARDff64abe2012-02-02 16:20:01 +0100106 *
Grant Likelye80beb22013-02-12 17:48:37 +0000107 * Example:
Jean-Christophe PLAGNIOL-VILLARDff64abe2012-02-02 16:20:01 +0100108 * gpios = <0
Grant Likelye80beb22013-02-12 17:48:37 +0000109 * &gpio1 1 2
Jean-Christophe PLAGNIOL-VILLARDff64abe2012-02-02 16:20:01 +0100110 * 0
Grant Likelye80beb22013-02-12 17:48:37 +0000111 * &gpio2 3 4>;
Jean-Christophe PLAGNIOL-VILLARDff64abe2012-02-02 16:20:01 +0100112 *
Grant Likelye80beb22013-02-12 17:48:37 +0000113 * The above example defines four GPIOs, two of which are not specified.
114 * This function will return '4'
Jean-Christophe PLAGNIOL-VILLARDff64abe2012-02-02 16:20:01 +0100115 */
Grant Likelye80beb22013-02-12 17:48:37 +0000116static inline int of_gpio_named_count(struct device_node *np, const char* propname)
117{
118 return of_count_phandle_with_args(np, propname, "#gpio-cells");
119}
120
121/**
122 * of_gpio_count() - Count GPIOs for a device
123 * @np: device node to count GPIOs for
124 *
125 * Same as of_gpio_named_count, but hard coded to use the 'gpios' property
126 */
127static inline int of_gpio_count(struct device_node *np)
Jean-Christophe PLAGNIOL-VILLARDff64abe2012-02-02 16:20:01 +0100128{
129 return of_gpio_named_count(np, "gpios");
130}
131
132/**
Alexandre Courbotaf8b6372013-10-17 10:21:37 -0700133 * of_get_gpiod_flags() - Get a GPIO descriptor and flags to use with GPIO API
John Bonesioa6b09192011-06-27 16:49:57 -0700134 * @np: device node to get GPIO from
135 * @index: index of the GPIO
136 * @flags: a flags pointer to fill in
137 *
Alexandre Courbotaf8b6372013-10-17 10:21:37 -0700138 * Returns GPIO descriptor to use with Linux generic GPIO API, or a errno
John Bonesioa6b09192011-06-27 16:49:57 -0700139 * value on the error condition. If @flags is not NULL the function also fills
140 * in flags for the GPIO.
141 */
Alexandre Courbotaf8b6372013-10-17 10:21:37 -0700142static inline struct gpio_desc *of_get_gpiod_flags(struct device_node *np,
143 int index, enum of_gpio_flags *flags)
144{
145 return of_get_named_gpiod_flags(np, "gpios", index, flags);
146}
147
John Bonesioa6b09192011-06-27 16:49:57 -0700148static inline int of_get_gpio_flags(struct device_node *np, int index,
149 enum of_gpio_flags *flags)
150{
151 return of_get_named_gpio_flags(np, "gpios", index, flags);
152}
153
154/**
155 * of_get_named_gpio() - Get a GPIO number to use with GPIO API
156 * @np: device node to get GPIO from
157 * @propname: Name of property containing gpio specifier(s)
158 * @index: index of the GPIO
159 *
160 * Returns GPIO number to use with Linux generic GPIO API, or one of the errno
161 * value on the error condition.
162 */
163static inline int of_get_named_gpio(struct device_node *np,
164 const char *propname, int index)
165{
166 return of_get_named_gpio_flags(np, propname, index, NULL);
167}
168
169/**
170 * of_get_gpio() - Get a GPIO number to use with GPIO API
Anton Vorontsovb908b532008-12-01 06:30:04 +0000171 * @np: device node to get GPIO from
172 * @index: index of the GPIO
173 *
174 * Returns GPIO number to use with Linux generic GPIO API, or one of the errno
175 * value on the error condition.
176 */
177static inline int of_get_gpio(struct device_node *np, int index)
178{
179 return of_get_gpio_flags(np, index, NULL);
180}
181
Anton Vorontsov863fbf42008-04-11 23:06:45 +1000182#endif /* __LINUX_OF_GPIO_H */