Re: [U-Boot] gpio: Question about gpio_set_value() implementation in spear_gpio.c

On 6/19/2013 7:14 PM, Axel Lin wrote:

Current code looks strange because no matter the value argument is 0 or 1 it always calls writel(1<< gpio,&regs->gpiodata[DATA_REG_ADDR(gpio)]);

And then gpio_get_value() always return 1.

I'm wondering if it needs to be fixed, something like below change:

diff --git a/drivers/gpio/spear_gpio.c b/drivers/gpio/spear_gpio.c index d3c728e..8878608 100644 --- a/drivers/gpio/spear_gpio.c +++ b/drivers/gpio/spear_gpio.c @@ -52,7 +52,10 @@ 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)]);
  
  

Yes, this is the right way. It was a blunder. I am wondering no one ever tried to set a ZERO on any GPIO..

Thanks for pointing out

Regards Vipin

return 0; }