nios2 : convert altera_pio to driver model

Convert altera_pio to driver model.

Signed-off-by: Thomas Chou <thomas@wytron.com.tw>
Acked-by: Chin Liang See <clsee@altera.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
diff --git a/arch/nios2/include/asm/gpio.h b/arch/nios2/include/asm/gpio.h
index 908381f..306ab4c 100644
--- a/arch/nios2/include/asm/gpio.h
+++ b/arch/nios2/include/asm/gpio.h
@@ -1,79 +1 @@
-/*
- * 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_ */
+#include <asm-generic/gpio.h>