of_gpio.h revision 863fbf4966a7ac301a4077e4a04d73e8abfdd7b2 
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/errno.h>
18#include <asm/gpio.h>
19
20#ifdef CONFIG_OF_GPIO
21
22/*
23 * Generic OF GPIO chip
24 */
25struct of_gpio_chip {
26	struct gpio_chip gc;
27	int gpio_cells;
28	int (*xlate)(struct of_gpio_chip *of_gc, struct device_node *np,
29		     const void *gpio_spec);
30};
31
32static inline struct of_gpio_chip *to_of_gpio_chip(struct gpio_chip *gc)
33{
34	return container_of(gc, struct of_gpio_chip, gc);
35}
36
37/*
38 * OF GPIO chip for memory mapped banks
39 */
40struct of_mm_gpio_chip {
41	struct of_gpio_chip of_gc;
42	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{
48	struct of_gpio_chip *of_gc = to_of_gpio_chip(gc);
49
50	return container_of(of_gc, struct of_mm_gpio_chip, of_gc);
51}
52
53extern int of_get_gpio(struct device_node *np, int index);
54extern int of_mm_gpiochip_add(struct device_node *np,
55			      struct of_mm_gpio_chip *mm_gc);
56extern int of_gpio_simple_xlate(struct of_gpio_chip *of_gc,
57				struct device_node *np,
58				const void *gpio_spec);
59#else
60
61/* Drivers may not strictly depend on the GPIO support, so let them link. */
62static inline int of_get_gpio(struct device_node *np, int index)
63{
64	return -ENOSYS;
65}
66
67#endif /* CONFIG_OF_GPIO */
68
69#endif /* __LINUX_OF_GPIO_H */
70