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