From: Axel Lin Date: Sun, 25 May 2014 02:31:18 +0000 (+0800) Subject: gpio: spear_gpio: Fix gpio_set_value() implementation X-Git-Tag: v2014.07~66 X-Git-Url: https://git.kernelconcepts.de/?p=karo-tx-uboot.git;a=commitdiff_plain;h=c0c374024dbd38b1045784cb2880ba21db552c54 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 Acked-by: Stefan Roese Reviewed-by: Vipin Kumar Reviewed-by: Michael Trimarchi --- diff --git a/drivers/gpio/spear_gpio.c b/drivers/gpio/spear_gpio.c index 367b670166..6fb4117dbe 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, ®s->gpiodata[DATA_REG_ADDR(gpio)]); + if (value) + writel(1 << gpio, ®s->gpiodata[DATA_REG_ADDR(gpio)]); + else + writel(0, ®s->gpiodata[DATA_REG_ADDR(gpio)]); return 0; }