Re: [PATCH v6 2/3] gpio: pca953x: define masks for addressing common and extended registers

From: Andy Shevchenko
Date: Wed May 16 2018 - 15:18:23 EST


On Wed, May 16, 2018 at 8:01 PM, H. Nikolaus Schaller <hns@xxxxxxxxxxxxx> wrote:
> These mask bits are to be used to map the extended register
> addreseses (which are defined for an unsupported 8-bit pcal chip)
> to 16 and 24 bit chips (pcal6524).
>
> Reviewed-by: Andy Shevchenko <andy.shevchenko@xxxxxxxxx>
> Signed-off-by: H. Nikolaus Schaller <hns@xxxxxxxxxxxxx>
> ---
> drivers/gpio/gpio-pca953x.c | 4 ++++
> 1 file changed, 4 insertions(+)
>
> diff --git a/drivers/gpio/gpio-pca953x.c b/drivers/gpio/gpio-pca953x.c
> index 2b667166e855..c0eb679e60d4 100644
> --- a/drivers/gpio/gpio-pca953x.c
> +++ b/drivers/gpio/gpio-pca953x.c
> @@ -56,6 +56,10 @@
> #define PCAL6524_DEBOUNCE 0x2d
>
> #define PCA_GPIO_MASK 0x00FF
> +
> +#define PCAL_GPIO_MASK GENMASK(4, 0)
> +#define PCAL_PINCTRL_MASK (~PCAL_GPIO_MASK)
> +

I give second thought about it, and think
either plain values, or second converted to its own explicit GENMASK
would be better.

(most confusing part to me is unknowness of the side of PINCTRL part
in the mask)


> #define PCA_INT 0x0100
> #define PCA_PCAL 0x0200
> #define PCA_LATCH_INT (PCA_PCAL | PCA_INT)
> --
> 2.12.2
>



--
With Best Regards,
Andy Shevchenko