mirror of
https://github.com/edk2-porting/linux-next.git
synced 2024-12-30 16:13:54 +08:00
749820928a
This function is used to count how many GPIOs are specified for a device node. Signed-off-by: Anton Vorontsov <avorontsov@ru.mvista.com> Signed-off-by: Paul Mackerras <paulus@samba.org>
106 lines
2.7 KiB
C
106 lines
2.7 KiB
C
/*
|
|
* OF helpers for the GPIO API
|
|
*
|
|
* Copyright (c) 2007-2008 MontaVista Software, Inc.
|
|
*
|
|
* Author: Anton Vorontsov <avorontsov@ru.mvista.com>
|
|
*
|
|
* This program is free software; you can redistribute it and/or modify
|
|
* it under the terms of the GNU General Public License as published by
|
|
* the Free Software Foundation; either version 2 of the License, or
|
|
* (at your option) any later version.
|
|
*/
|
|
|
|
#ifndef __LINUX_OF_GPIO_H
|
|
#define __LINUX_OF_GPIO_H
|
|
|
|
#include <linux/compiler.h>
|
|
#include <linux/kernel.h>
|
|
#include <linux/errno.h>
|
|
#include <linux/gpio.h>
|
|
|
|
struct device_node;
|
|
|
|
/*
|
|
* 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
|
|
|
|
/*
|
|
* Generic OF GPIO chip
|
|
*/
|
|
struct of_gpio_chip {
|
|
struct gpio_chip gc;
|
|
int gpio_cells;
|
|
int (*xlate)(struct of_gpio_chip *of_gc, struct device_node *np,
|
|
const void *gpio_spec, enum of_gpio_flags *flags);
|
|
};
|
|
|
|
static inline struct of_gpio_chip *to_of_gpio_chip(struct gpio_chip *gc)
|
|
{
|
|
return container_of(gc, struct of_gpio_chip, gc);
|
|
}
|
|
|
|
/*
|
|
* OF GPIO chip for memory mapped banks
|
|
*/
|
|
struct of_mm_gpio_chip {
|
|
struct of_gpio_chip of_gc;
|
|
void (*save_regs)(struct of_mm_gpio_chip *mm_gc);
|
|
void __iomem *regs;
|
|
};
|
|
|
|
static inline struct of_mm_gpio_chip *to_of_mm_gpio_chip(struct gpio_chip *gc)
|
|
{
|
|
struct of_gpio_chip *of_gc = to_of_gpio_chip(gc);
|
|
|
|
return container_of(of_gc, struct of_mm_gpio_chip, of_gc);
|
|
}
|
|
|
|
extern int of_get_gpio_flags(struct device_node *np, int index,
|
|
enum of_gpio_flags *flags);
|
|
extern unsigned int of_gpio_count(struct device_node *np);
|
|
|
|
extern int of_mm_gpiochip_add(struct device_node *np,
|
|
struct of_mm_gpio_chip *mm_gc);
|
|
extern int of_gpio_simple_xlate(struct of_gpio_chip *of_gc,
|
|
struct device_node *np,
|
|
const void *gpio_spec,
|
|
enum of_gpio_flags *flags);
|
|
#else
|
|
|
|
/* Drivers may not strictly depend on the GPIO support, so let them link. */
|
|
static inline int of_get_gpio_flags(struct device_node *np, int index,
|
|
enum of_gpio_flags *flags)
|
|
{
|
|
return -ENOSYS;
|
|
}
|
|
|
|
static inline unsigned int of_gpio_count(struct device_node *np)
|
|
{
|
|
return 0;
|
|
}
|
|
|
|
#endif /* CONFIG_OF_GPIO */
|
|
|
|
/**
|
|
* 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 /* __LINUX_OF_GPIO_H */
|