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authorSanjeev Premi <premi@ti.com>2011-09-08 10:47:25 -0400
committerAlbert ARIBAUD <albert.u.boot@aribaud.net>2011-09-13 08:25:15 +0200
commit81bdc155c72ef9e093b388b90c58d8134d870976 (patch)
tree0bec6a9be05cd6067b02a0cc265ebd36a04b45bd
parent205c0658906751f343349f29092385fb45a7d3e8 (diff)
downloadu-boot-linaro-stable-81bdc155c72ef9e093b388b90c58d8134d870976.tar.gz
omap: gpio: Use generic API
Convert all OMAP specific functions to use the common API definitions in include/asm/gpio.h. In the process, made few additional changes: - Use -EINVAL consistently. -1 was used in many places. - Removed one-liner static functions that were used only once. Replaced the content as necessary. - Combines implementation of functions omap_get_gpio_dataout() and omap_get_gpio_datain(). To do so, new static function _get_gpio_direction() was added. Signed-off-by: Sanjeev Premi <premi@ti.com> Signed-off-by: Sandeep Paulraj <s-paulraj@ti.com>
-rw-r--r--arch/arm/cpu/armv7/omap-common/gpio.c113
-rw-r--r--arch/arm/include/asm/omap_gpio.h15
2 files changed, 82 insertions, 46 deletions
diff --git a/arch/arm/cpu/armv7/omap-common/gpio.c b/arch/arm/cpu/armv7/omap-common/gpio.c
index 47495244e..e62c6f4eb 100644
--- a/arch/arm/cpu/armv7/omap-common/gpio.c
+++ b/arch/arm/cpu/armv7/omap-common/gpio.c
@@ -40,6 +40,9 @@
#include <asm/io.h>
#include <asm/errno.h>
+#define OMAP_GPIO_DIR_OUT 0
+#define OMAP_GPIO_DIR_IN 1
+
static inline const struct gpio_bank *get_gpio_bank(int gpio)
{
return &omap_gpio_bank[gpio >> 5];
@@ -53,17 +56,17 @@ static inline int get_gpio_index(int gpio)
static inline int gpio_valid(int gpio)
{
if (gpio < 0)
- return -1;
+ return -EINVAL;
if (gpio < 192)
return 0;
- return -1;
+ return -EINVAL;
}
static int check_gpio(int gpio)
{
if (gpio_valid(gpio) < 0) {
printf("ERROR : check_gpio: invalid GPIO %d\n", gpio);
- return -1;
+ return -EINVAL;
}
return 0;
}
@@ -89,14 +92,29 @@ static void _set_gpio_direction(const struct gpio_bank *bank, int gpio,
__raw_writel(l, reg);
}
-void omap_set_gpio_direction(int gpio, int is_input)
+/**
+ * Get the direction of the GPIO by reading the GPIO_OE register
+ * corresponding to the specified bank.
+ */
+static int _get_gpio_direction(const struct gpio_bank *bank, int gpio)
{
- const struct gpio_bank *bank;
+ void *reg = bank->base;
+ u32 v;
- if (check_gpio(gpio) < 0)
- return;
- bank = get_gpio_bank(gpio);
- _set_gpio_direction(bank, get_gpio_index(gpio), is_input);
+ switch (bank->method) {
+ case METHOD_GPIO_24XX:
+ reg += OMAP_GPIO_OE;
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ v = __raw_readl(reg);
+
+ if (v & (1 << gpio))
+ return OMAP_GPIO_DIR_IN;
+ else
+ return OMAP_GPIO_DIR_OUT;
}
static void _set_gpio_dataout(const struct gpio_bank *bank, int gpio,
@@ -121,20 +139,27 @@ static void _set_gpio_dataout(const struct gpio_bank *bank, int gpio,
__raw_writel(l, reg);
}
-void omap_set_gpio_dataout(int gpio, int enable)
+/**
+ * Set value of the specified gpio
+ */
+void gpio_set_value(int gpio, int value)
{
const struct gpio_bank *bank;
if (check_gpio(gpio) < 0)
return;
bank = get_gpio_bank(gpio);
- _set_gpio_dataout(bank, get_gpio_index(gpio), enable);
+ _set_gpio_dataout(bank, get_gpio_index(gpio), value);
}
-int omap_get_gpio_datain(int gpio)
+/**
+ * Get value of the specified gpio
+ */
+int gpio_get_value(int gpio)
{
const struct gpio_bank *bank;
void *reg;
+ int input;
if (check_gpio(gpio) < 0)
return -EINVAL;
@@ -142,7 +167,17 @@ int omap_get_gpio_datain(int gpio)
reg = bank->base;
switch (bank->method) {
case METHOD_GPIO_24XX:
- reg += OMAP_GPIO_DATAIN;
+ input = _get_gpio_direction(bank, get_gpio_index(gpio));
+ switch (input) {
+ case OMAP_GPIO_DIR_IN:
+ reg += OMAP_GPIO_DATAIN;
+ break;
+ case OMAP_GPIO_DIR_OUT:
+ reg += OMAP_GPIO_DATAOUT;
+ break;
+ default:
+ return -EINVAL;
+ }
break;
default:
return -EINVAL;
@@ -151,32 +186,45 @@ int omap_get_gpio_datain(int gpio)
& (1 << get_gpio_index(gpio))) != 0;
}
-int omap_get_gpio_dataout(int gpio)
+/**
+ * Set gpio direction as input
+ */
+int gpio_direction_input(unsigned gpio)
{
- struct gpio_bank *bank;
- void *reg;
+ const struct gpio_bank *bank;
if (check_gpio(gpio) < 0)
return -EINVAL;
+
bank = get_gpio_bank(gpio);
- reg = bank->base;
- switch (bank->method) {
- case METHOD_GPIO_24XX:
- reg += OMAP_GPIO_DATAOUT;
- break;
- default:
- return -EINVAL;
- }
- return (__raw_readl(reg)
- & (1 << get_gpio_index(gpio))) != 0;
+ _set_gpio_direction(bank, get_gpio_index(gpio), 1);
+
+ return 0;
}
-static void _reset_gpio(const struct gpio_bank *bank, int gpio)
+/**
+ * Set gpio direction as output
+ */
+int gpio_direction_output(unsigned gpio, int value)
{
- _set_gpio_direction(bank, get_gpio_index(gpio), 1);
+ const struct gpio_bank *bank;
+
+ if (check_gpio(gpio) < 0)
+ return -EINVAL;
+
+ bank = get_gpio_bank(gpio);
+ _set_gpio_dataout(bank, get_gpio_index(gpio), value);
+ _set_gpio_direction(bank, get_gpio_index(gpio), 0);
+
+ return 0;
}
-int omap_request_gpio(int gpio)
+/**
+ * Request a gpio before using it.
+ *
+ * NOTE: Argument 'label' is unused.
+ */
+int gpio_request(int gpio, const char *label)
{
if (check_gpio(gpio) < 0)
return -EINVAL;
@@ -184,7 +232,10 @@ int omap_request_gpio(int gpio)
return 0;
}
-void omap_free_gpio(int gpio)
+/**
+ * Reset and free the gpio after using it.
+ */
+void gpio_free(unsigned gpio)
{
const struct gpio_bank *bank;
@@ -192,5 +243,5 @@ void omap_free_gpio(int gpio)
return;
bank = get_gpio_bank(gpio);
- _reset_gpio(bank, gpio);
+ _set_gpio_direction(bank, get_gpio_index(gpio), 1);
}
diff --git a/arch/arm/include/asm/omap_gpio.h b/arch/arm/include/asm/omap_gpio.h
index 874157250..516cc4260 100644
--- a/arch/arm/include/asm/omap_gpio.h
+++ b/arch/arm/include/asm/omap_gpio.h
@@ -49,19 +49,4 @@ extern const struct gpio_bank *const omap_gpio_bank;
#define METHOD_GPIO_24XX 4
-/* This is the interface */
-
-/* Request a gpio before using it */
-int omap_request_gpio(int gpio);
-/* Reset and free a gpio after using it */
-void omap_free_gpio(int gpio);
-/* Sets the gpio as input or output */
-void omap_set_gpio_direction(int gpio, int is_input);
-/* Set or clear a gpio output */
-void omap_set_gpio_dataout(int gpio, int enable);
-/* Get the value of a gpio input */
-int omap_get_gpio_datain(int gpio);
-/* Get the value of a gpio output */
-int omap_get_gpio_dataout(int gpio);
-
#endif /* _GPIO_H_ */