--- /dev/null
+/*
+ * 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_ */