Re: [U-Boot] [PATCH v2] gpio: spear_gpio: Fix gpio_set_value() implementation
Hi Axel,
On Mon, 16 Sep 2013 08:35:41 +0800, Axel Lin axel@ingics.com
wrote:
In current gpio_set_value() implementation, it always sets the gpio control
bit
no matter the value argument is 0 or 1. Thus the GPIOs never set to low.
This patch fixes this bug.
The address bus is used as a mask on read/write operations, so that
independent
software drivers can set their GPIO bits without affecting any other pins in a
single write operation. Thus we don't need a read-modify-write to update the
register.
Signed-off-by: Axel Lin axel@ingics.com
Acked-by: Stefan Roese s...@denx.de
Reviewed-by: Vipin Kumar vipin.ku...@st.com
Reviewed-by: Michael Trimarchi mich...@amarulasolutions.com
---
v2: Update commit log to explain why a read-modify-write is not necessary
for clearing specific GPIO bit.
Also added Michael Trimarchi's reviewed-by tag since he does review the
patch and said the patch is fine.
drivers/gpio/spear_gpio.c | 5 -
1 file changed, 4 insertions(+), 1 deletion(-)
diff --git a/drivers/gpio/spear_gpio.c b/drivers/gpio/spear_gpio.c
index 367b670..6fb4117 100644
--- a/drivers/gpio/spear_gpio.c
+++ b/drivers/gpio/spear_gpio.c
@@ -36,7 +36,10 @@ int gpio_set_value(unsigned gpio, int value)
{
struct gpio_regs *regs = (struct gpio_regs *)CONFIG_GPIO_BASE;
- writel(1 gpio, regs-gpiodata[DATA_REG_ADDR(gpio)]);
+ if (value)
+ writel(1 gpio, regs-gpiodata[DATA_REG_ADDR(gpio)]);
+ else
+ writel(0, regs-gpiodata[DATA_REG_ADDR(gpio)]);
return 0;
}
Applied to u-boot-arm/master, thanks!
Amicalement,
--
Albert.
___
U-Boot mailing list
U-Boot@lists.denx.de
http://lists.denx.de/mailman/listinfo/u-boot
[U-Boot] [PATCH v2] gpio: spear_gpio: Fix gpio_set_value() implementation
In current gpio_set_value() implementation, it always sets the gpio control bit
no matter the value argument is 0 or 1. Thus the GPIOs never set to low.
This patch fixes this bug.
The address bus is used as a mask on read/write operations, so that independent
software drivers can set their GPIO bits without affecting any other pins in a
single write operation. Thus we don't need a read-modify-write to update the
register.
Signed-off-by: Axel Lin axel@ingics.com
Acked-by: Stefan Roese s...@denx.de
Reviewed-by: Vipin Kumar vipin.ku...@st.com
Reviewed-by: Michael Trimarchi mich...@amarulasolutions.com
---
v2: Update commit log to explain why a read-modify-write is not necessary
for clearing specific GPIO bit.
Also added Michael Trimarchi's reviewed-by tag since he does review the
patch and said the patch is fine.
drivers/gpio/spear_gpio.c | 5 -
1 file changed, 4 insertions(+), 1 deletion(-)
diff --git a/drivers/gpio/spear_gpio.c b/drivers/gpio/spear_gpio.c
index 367b670..6fb4117 100644
--- a/drivers/gpio/spear_gpio.c
+++ b/drivers/gpio/spear_gpio.c
@@ -36,7 +36,10 @@ int gpio_set_value(unsigned gpio, int value)
{
struct gpio_regs *regs = (struct gpio_regs *)CONFIG_GPIO_BASE;
- writel(1 gpio, regs-gpiodata[DATA_REG_ADDR(gpio)]);
+ if (value)
+ writel(1 gpio, regs-gpiodata[DATA_REG_ADDR(gpio)]);
+ else
+ writel(0, regs-gpiodata[DATA_REG_ADDR(gpio)]);
return 0;
}
--
1.8.1.2
___
U-Boot mailing list
U-Boot@lists.denx.de
http://lists.denx.de/mailman/listinfo/u-boot
