Re: [PATCH] gpio: mxs: Use set and clear capabilities of the gpiocontroller

From: Shawn Guo
Date: Wed May 01 2013 - 22:45:33 EST


On Mon, Apr 29, 2013 at 04:07:18PM +0200, Maxime Ripard wrote:
> The current driver doesn't use the set and clear registers found on the
> mxs gpio controller.
>
> This leads the generic gpio controller to be using some internal value
> to avoid looking up the value stored in the registers, making it behave
> pretty much like a cache.
>
> This raises some coherency problem when a gpio is not modified by the
> gpio controller, while it can easily be fixed by using the set and clear
> registers.
>
> Signed-off-by: Maxime Ripard <maxime.ripard@xxxxxxxxxxxxxxxxxx>

Acked-by: Shawn Guo <shawn.guo@xxxxxxxxxx>

> ---
> drivers/gpio/gpio-mxs.c | 3 ++-
> 1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/gpio/gpio-mxs.c b/drivers/gpio/gpio-mxs.c
> index 25000b0..f8e6af2 100644
> --- a/drivers/gpio/gpio-mxs.c
> +++ b/drivers/gpio/gpio-mxs.c
> @@ -326,7 +326,8 @@ static int mxs_gpio_probe(struct platform_device *pdev)
>
> err = bgpio_init(&port->bgc, &pdev->dev, 4,
> port->base + PINCTRL_DIN(port),
> - port->base + PINCTRL_DOUT(port), NULL,
> + port->base + PINCTRL_DOUT(port) + MXS_SET,
> + port->base + PINCTRL_DOUT(port) + MXS_CLR,
> port->base + PINCTRL_DOE(port), NULL, 0);
> if (err)
> goto out_irqdesc_free;
> --
> 1.8.1.2
>

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