u-boot/arch/nios2/include/asm/gpio.h
Joachim Foerster 03d67e1276 gpio: Add driver for Altera's PIO core
This driver may handle multiple PIO cores and thus needs to be
setup by calling the altera_pio_init() function within the early
board setup routine.

The driver comes with some extras, see below the copyleft header.

Signed-off-by: Joachim Foerster <joachim.foerster@missinglinkelectronics.com>
Tested-by: Thomas Chou <thomas@wytron.com.tw>
Signed-off-by: Thomas Chou <thomas@wytron.com.tw>
2011-10-28 09:50:49 +08:00

79 lines
1.9 KiB
C

/*
* nios2 gpio driver
*
* This gpio core is described in http://nioswiki.com/GPIO
* bit[0] data
* bit[1] output enable
*
* When CONFIG_SYS_GPIO_BASE is not defined, the board may either
* provide its own driver or the altera_pio driver may be used.
*
* Copyright (C) 2010 Thomas Chou <thomas@wytron.com.tw>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#ifndef _ASM_NIOS2_GPIO_H_
#define _ASM_NIOS2_GPIO_H_
#ifdef CONFIG_SYS_GPIO_BASE
#include <asm/io.h>
static inline int gpio_request(unsigned gpio, const char *label)
{
return 0;
}
static inline int gpio_free(unsigned gpio)
{
return 0;
}
static inline int gpio_direction_input(unsigned gpio)
{
writel(1, CONFIG_SYS_GPIO_BASE + (gpio << 2));
return 0;
}
static inline int gpio_direction_output(unsigned gpio, int value)
{
writel(value ? 3 : 2, CONFIG_SYS_GPIO_BASE + (gpio << 2));
return 0;
}
static inline int gpio_get_value(unsigned gpio)
{
return readl(CONFIG_SYS_GPIO_BASE + (gpio << 2));
}
static inline void gpio_set_value(unsigned gpio, int value)
{
writel(value ? 3 : 2, CONFIG_SYS_GPIO_BASE + (gpio << 2));
}
static inline int gpio_is_valid(int number)
{
return ((unsigned)number) < CONFIG_SYS_GPIO_WIDTH;
}
#else
#ifdef CONFIG_ALTERA_PIO
extern int altera_pio_init(u32 base, u8 width, char iot,
u32 rstval, u32 negmask,
const char *label);
extern void altera_pio_info(void);
#define gpio_status() altera_pio_info()
#endif
extern int gpio_request(unsigned gpio, const char *label);
extern int gpio_free(unsigned gpio);
extern int gpio_direction_input(unsigned gpio);
extern int gpio_direction_output(unsigned gpio, int value);
extern int gpio_get_value(unsigned gpio);
extern void gpio_set_value(unsigned gpio, int value);
extern int gpio_is_valid(int number);
#endif /* CONFIG_SYS_GPIO_BASE */
#endif /* _ASM_NIOS2_GPIO_H_ */