Re: [PATCH v2 01/10] pinctrl: sh-pfc: Validate fixed-size field widths at build time

[Simon Horman <horms@xxxxxxxxxxxx>]

On Fri, Jan 25, 2019 at 05:52:56PM +0100, Geert Uytterhoeven wrote:
> Add a build-time check, to ensure the register and field widths in
> descriptors for config registers with fixed-width fields are sane.
> This helps catching bugs early.
> 
> Signed-off-by: Geert Uytterhoeven <geert+renesas@xxxxxxxxx>
> ---
> v2:
>   - Convert from run-time to build-time check.

Nice :)

Reviewed-by: Simon Horman <horms+renesas@xxxxxxxxxxxx>

> ---
>  drivers/pinctrl/sh-pfc/sh_pfc.h | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/pinctrl/sh-pfc/sh_pfc.h b/drivers/pinctrl/sh-pfc/sh_pfc.h
> index 46d477ff510921f3..56016cb76769c97b 100644
> --- a/drivers/pinctrl/sh-pfc/sh_pfc.h
> +++ b/drivers/pinctrl/sh-pfc/sh_pfc.h
> @@ -126,7 +126,8 @@ struct pinmux_cfg_reg {
>   * one for each possible combination of the register field bit values.
>   */
>  #define PINMUX_CFG_REG(name, r, r_width, f_width) \
> -	.reg = r, .reg_width = r_width, .field_width = f_width,		\
> +	.reg = r, .reg_width = r_width,					\
> +	.field_width = f_width + BUILD_BUG_ON_ZERO(r_width % f_width),	\
>  	.enum_ids = (const u16 [(r_width / f_width) * (1 << f_width)])
>  
>  /*
> -- 
> 2.17.1
>