Re: [PATCH v2 2/7] usb: typec: mux: Add CONFIG guards for functions

[AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>]

Il 09/06/22 20:09, Prashant Malani ha scritto:
> There are some drivers that can use the Type C mux API, but don't have
> to. Introduce CONFIG guards for the mux functions so that drivers can
> include the header file and not run into compilation errors on systems
> which don't have CONFIG_TYPEC enabled. When CONFIG_TYPEC is not enabled,
> the Type C mux functions will be stub versions of the original calls.
> 
> Reported-by: kernel test robot <lkp@intel.com>
> Signed-off-by: Prashant Malani <pmalani@chromium.org>
> ---
> 
> Changes since v1:
> - Added static inline to stub functions.
> - Updated function signature of stub functions from "struct typec_mux"
>    to "struct typec_mux_dev" in accordance with updates from commit
>    713fd49b430c ("usb: typec: mux: Introduce indirection")
> 
>   include/linux/usb/typec_mux.h | 38 +++++++++++++++++++++++++++++++++++
>   1 file changed, 38 insertions(+)
> 
> diff --git a/include/linux/usb/typec_mux.h b/include/linux/usb/typec_mux.h
> index ee57781dcf28..9eda6146fd26 100644
> --- a/include/linux/usb/typec_mux.h
> +++ b/include/linux/usb/typec_mux.h
> @@ -58,6 +58,8 @@ struct typec_mux_desc {
>   	void *drvdata;
>   };
>   
> +#if IS_ENABLED(CONFIG_TYPEC) || IS_MODULE(CONFIG_TYPEC)

IS_ENABLED(x) evaluates to 1 when (x == 'y' || x == 'm')
IS_MODULE(x) evaluates to 1 when              (x == 'm')

....this means that a IS_ENABLED(CONFIG_TYPEC) check is enough, and
the latter is redundant.

Regards,
Angelo