linux_dsm_epyc7002/include/linux/of_gpio.h
Grant Likely 15c9a0acc3 of: create of_phandle_args to simplify return of phandle parsing data
of_parse_phandle_with_args() needs to return quite a bit of data.  Rather
than making each datum a separate **out_ argument, this patch creates
struct of_phandle_args to contain all the returned data and reworks the
user of the function.  This patch also enables of_parse_phandle_with_args()
to return the device node pointer for the phandle node.

This patch also ends up being fairly major surgery to
of_parse_handle_with_args().  The existing structure didn't work well
when extending to use of_phandle_args, and I discovered bugs during testing.
I also took the opportunity to rename the function to be like the
existing of_parse_phandle().

v2: - moved declaration of of_phandle_args to fix compile on non-DT builds
    - fixed incorrect index in example usage
    - fixed incorrect return code handling for empty entries

Reviewed-by: Shawn Guo <shawn.guo@freescale.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2011-12-12 13:40:16 -07:00

136 lines
3.8 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>
#include <linux/of.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
/*
* OF GPIO chip for memory mapped banks
*/
struct of_mm_gpio_chip {
struct gpio_chip 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)
{
return container_of(gc, struct of_mm_gpio_chip, gc);
}
extern int of_get_named_gpio_flags(struct device_node *np,
const char *list_name, 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 void of_gpiochip_add(struct gpio_chip *gc);
extern void of_gpiochip_remove(struct gpio_chip *gc);
extern struct gpio_chip *of_node_to_gpiochip(struct device_node *np);
extern int of_gpio_simple_xlate(struct gpio_chip *gc,
const struct of_phandle_args *gpiospec,
u32 *flags);
#else /* CONFIG_OF_GPIO */
/* Drivers may not strictly depend on the GPIO support, so let them link. */
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;
}
static inline unsigned int of_gpio_count(struct device_node *np)
{
return 0;
}
static inline int of_gpio_simple_xlate(struct gpio_chip *gc,
const struct of_phandle_args *gpiospec,
u32 *flags)
{
return -ENOSYS;
}
static inline void of_gpiochip_add(struct gpio_chip *gc) { }
static inline void of_gpiochip_remove(struct gpio_chip *gc) { }
#endif /* CONFIG_OF_GPIO */
/**
* of_get_gpio_flags() - Get a GPIO number and flags to use with GPIO API
* @np: device node to get GPIO from
* @index: index of the GPIO
* @flags: a flags pointer to fill in
*
* Returns GPIO number to use with Linux generic GPIO API, or one of the errno
* value on the error condition. If @flags is not NULL the function also fills
* in flags for the GPIO.
*/
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);
}
/**
* of_get_named_gpio() - Get a GPIO number to use with GPIO API
* @np: device node to get GPIO from
* @propname: Name of property containing gpio specifier(s)
* @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_named_gpio(struct device_node *np,
const char *propname, int index)
{
return of_get_named_gpio_flags(np, propname, 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 /* __LINUX_OF_GPIO_H */