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authorThomas Chou <thomas@wytron.com.tw>2010-04-30 11:34:13 +0800
committerScott McNutt <smcnutt@psyent.com>2010-05-28 10:56:03 -0400
commitcedd341d551b6b705e97ab1953a87575b9ff9ef9 (patch)
tree3ab675b58aed1dd5a80f09c16a7a03198fdbe560 /arch/nios2
parent01f03bda5b22e5aeae5f02fd537da97a41485c73 (diff)
downloadu-boot-linaro-stable-cedd341d551b6b705e97ab1953a87575b9ff9ef9.tar.gz
nios2: add gpio support
This patch adds driver for a trivial gpio core, which is described in http://nioswiki.com/GPIO. It is used for gpio led and nand flash interface in u-boot. When CONFIG_SYS_GPIO_BASE is not defined, board may provide its own driver. Signed-off-by: Thomas Chou <thomas@wytron.com.tw> Tested-by: Ian Abbott <abbotti@mev.co.uk> Signed-off-by: Scott McNutt <smcnutt@psyent.com>
Diffstat (limited to 'arch/nios2')
-rw-r--r--arch/nios2/include/asm/gpio.h52
1 files changed, 52 insertions, 0 deletions
diff --git a/arch/nios2/include/asm/gpio.h b/arch/nios2/include/asm/gpio.h
new file mode 100644
index 000000000..76c425e68
--- /dev/null
+++ b/arch/nios2/include/asm/gpio.h
@@ -0,0 +1,52 @@
+/*
+ * 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, board may provide
+ * its own driver.
+ *
+ * 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_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));
+}
+#else
+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);
+#endif /* CONFIG_SYS_GPIO_BASE */
+
+#endif /* _ASM_NIOS2_GPIO_H_ */