[U-Boot] [PATCH 2/9 v4] i.MX31: add a simple gpio driver
Anatolij Gustschin
agust at denx.de
Sat Feb 7 01:18:07 CET 2009
From: Guennadi Liakhovetski <lg at denx.de>
This is a minimal driver, so far only managing output. It will
be used by the mxc_spi.c driver.
Signed-off-by: Guennadi Liakhovetski <lg at denx.de>
Signed-off-by: Anatolij Gustschin <agust at denx.de>
---
Changes since v1: alphabetical order, typo in copyright fixed, use
ARRAY_SIZE.
Changes since v2: fixed wrong indentation in int mx31_gpio_direction()
declaration.
Changes since v3: use macros defined in
"mx31: add GPIO registers definitions" patch by Ilya Yanok.
After an ACK from Jean-Christophe I'm going to push it
via video tree.
Anatolij
drivers/gpio/Makefile | 3 +-
drivers/gpio/mx31_gpio.c | 73 ++++++++++++++++++++++++++++++++++++++
include/asm-arm/arch-mx31/mx31.h | 20 ++++++++++
3 files changed, 95 insertions(+), 1 deletions(-)
create mode 100644 drivers/gpio/mx31_gpio.c
diff --git a/drivers/gpio/Makefile b/drivers/gpio/Makefile
index dd618ed..f10144f 100644
--- a/drivers/gpio/Makefile
+++ b/drivers/gpio/Makefile
@@ -25,7 +25,8 @@ include $(TOPDIR)/config.mk
LIB := $(obj)libgpio.a
-COBJS-$(CONFIG_PCA953X) += pca953x.o
+COBJS-$(CONFIG_MX31_GPIO) += mx31_gpio.o
+COBJS-$(CONFIG_PCA953X) += pca953x.o
COBJS := $(COBJS-y)
SRCS := $(COBJS:.o=.c)
diff --git a/drivers/gpio/mx31_gpio.c b/drivers/gpio/mx31_gpio.c
new file mode 100644
index 0000000..737aafa
--- /dev/null
+++ b/drivers/gpio/mx31_gpio.c
@@ -0,0 +1,73 @@
+/*
+ * Copyright (C) 2009
+ * Guennadi Liakhovetski, DENX Software Engineering, <lg at denx.de>
+ *
+ * See file CREDITS for list of people who contributed to this
+ * project.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of
+ * the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
+ * MA 02111-1307 USA
+ */
+#include <common.h>
+#include <asm/arch/mx31.h>
+#include <asm/arch/mx31-regs.h>
+
+/* GPIO port description */
+static unsigned long gpio_ports[] = {
+ [0] = GPIO1_BASE,
+ [1] = GPIO2_BASE,
+ [2] = GPIO3_BASE,
+};
+
+int mx31_gpio_direction(unsigned int gpio, enum mx31_gpio_direction direction)
+{
+ unsigned int port = gpio >> 5;
+ u32 l;
+
+ if (port >= ARRAY_SIZE(gpio_ports))
+ return 1;
+
+ gpio &= 0x1f;
+
+ l = __REG(gpio_ports[port] + GPIO_GDIR);
+ switch (direction) {
+ case MX31_GPIO_DIRECTION_OUT:
+ l |= 1 << gpio;
+ break;
+ case MX31_GPIO_DIRECTION_IN:
+ l &= ~(1 << gpio);
+ }
+ __REG(gpio_ports[port] + GPIO_GDIR) = l;
+
+ return 0;
+}
+
+void mx31_gpio_set(unsigned int gpio, unsigned int value)
+{
+ unsigned int port = gpio >> 5;
+ u32 l;
+
+ if (port >= ARRAY_SIZE(gpio_ports))
+ return;
+
+ gpio &= 0x1f;
+
+ l = __REG(gpio_ports[port] + GPIO_DR);
+ if (value)
+ l |= 1 << gpio;
+ else
+ l &= ~(1 << gpio);
+ __REG(gpio_ports[port] + GPIO_DR) = l;
+}
diff --git a/include/asm-arm/arch-mx31/mx31.h b/include/asm-arm/arch-mx31/mx31.h
index 0552c27..1d475dd 100644
--- a/include/asm-arm/arch-mx31/mx31.h
+++ b/include/asm-arm/arch-mx31/mx31.h
@@ -27,4 +27,24 @@
extern u32 mx31_get_ipg_clk(void);
extern void mx31_gpio_mux(unsigned long mode);
+enum mx31_gpio_direction {
+ MX31_GPIO_DIRECTION_IN,
+ MX31_GPIO_DIRECTION_OUT,
+};
+
+#ifdef CONFIG_MX31_GPIO
+extern int mx31_gpio_direction(unsigned int gpio,
+ enum mx31_gpio_direction direction);
+extern void mx31_gpio_set(unsigned int gpio, unsigned int value);
+#else
+static inline int mx31_gpio_direction(unsigned int gpio,
+ enum mx31_gpio_direction direction)
+{
+ return 1;
+}
+static inline void mx31_gpio_set(unsigned int gpio, unsigned int value)
+{
+}
+#endif
+
#endif /* __ASM_ARCH_MX31_H */
--
1.5.3.3
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