xref: /openbmc/u-boot/arch/nios2/include/asm/gpio.h (revision 15855700)
1 /*
2  * nios2 gpio driver
3  *
4  * This gpio core is described in http://nioswiki.com/GPIO
5  * bit[0] data
6  * bit[1] output enable
7  *
8  * when CONFIG_SYS_GPIO_BASE is not defined, board may provide
9  * its own driver.
10  *
11  * Copyright (C) 2010 Thomas Chou <thomas@wytron.com.tw>
12  *
13  * This program is free software; you can redistribute it and/or modify
14  * it under the terms of the GNU General Public License version 2 as
15  * published by the Free Software Foundation.
16  */
17 
18 #ifndef _ASM_NIOS2_GPIO_H_
19 #define _ASM_NIOS2_GPIO_H_
20 
21 #ifdef CONFIG_SYS_GPIO_BASE
22 #include <asm/io.h>
23 
24 static inline int gpio_direction_input(unsigned gpio)
25 {
26 	writel(1, CONFIG_SYS_GPIO_BASE + (gpio << 2));
27 	return 0;
28 }
29 
30 static inline int gpio_direction_output(unsigned gpio, int value)
31 {
32 	writel(value ? 3 : 2, CONFIG_SYS_GPIO_BASE + (gpio << 2));
33 	return 0;
34 }
35 
36 static inline int gpio_get_value(unsigned gpio)
37 {
38 	return readl(CONFIG_SYS_GPIO_BASE + (gpio << 2));
39 }
40 
41 static inline void gpio_set_value(unsigned gpio, int value)
42 {
43 	writel(value ? 3 : 2, CONFIG_SYS_GPIO_BASE + (gpio << 2));
44 }
45 #else
46 extern int gpio_direction_input(unsigned gpio);
47 extern int gpio_direction_output(unsigned gpio, int value);
48 extern int gpio_get_value(unsigned gpio);
49 extern void gpio_set_value(unsigned gpio, int value);
50 #endif /* CONFIG_SYS_GPIO_BASE */
51 
52 #endif /* _ASM_NIOS2_GPIO_H_ */
53