[U-Boot] [PATCH] mxc: Make gpio_get_value() use PSR

[Stefano Babic]

On 20/08/2012 22:55, Benoît Thébaudeau wrote:
> gpio_get_value() should use PSR like Linux, not DR, because DR does not always
> reflect the pin state, while PSR does. This is especially useful to detect a
> short circuit on a GPIO pin configured as output, or to read the level of a pin
> controlled by a non-GPIO IOMUX function.
> 
> Signed-off-by: Benoît Thébaudeau <benoit.thebaudeau at advansee.com>
> Cc: Stefano Babic <sbabic at denx.de>
> ---
> This patch depends on http://patchwork.ozlabs.org/patch/178694/ .
> 
>  .../drivers/gpio/mxc_gpio.c                        |    2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git u-boot-imx-84ab1cb.orig/drivers/gpio/mxc_gpio.c u-boot-imx-84ab1cb/drivers/gpio/mxc_gpio.c
> index 6615535..e9bf278 100644
> --- u-boot-imx-84ab1cb.orig/drivers/gpio/mxc_gpio.c
> +++ u-boot-imx-84ab1cb/drivers/gpio/mxc_gpio.c
> @@ -116,7 +116,7 @@ int gpio_get_value(unsigned gpio)
>  
>  	regs = (struct gpio_regs *)gpio_ports[port];
>  
> -	val = (readl(&regs->gpio_dr) >> gpio) & 0x01;
> +	val = (readl(&regs->gpio_psr) >> gpio) & 0x01;
>  
>  	return val;
>  }
> 

Kernel does the same.

Acked-by: Stefano Babic <sbabic at denx.de>

Best regards,
Stefano Babic

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