Re: [PATCH] drm: bridge: anx7625: enforce CONFIG_USB_ROLE_SWITCH dependency

[Neil Armstrong <neil.armstrong@linaro.org>]

On 3/4/26 09:35, Arnd Bergmann wrote:
> From: Arnd Bergmann <arnd@arndb.de>
> 
> When CONFIG_TYPEC is enabled, but USB_ROLE_SWITCH=m, the anx7625 driver
> fails to link as built-in:
> 
> aarch64-linux-ld: drivers/gpu/drm/bridge/analogix/anx7625.o: in function `anx7625_i2c_remove':
> anx7625.c:(.text+0x6ec): undefined reference to `usb_role_switch_put'
> aarch64-linux-ld: drivers/gpu/drm/bridge/analogix/anx7625.o: in function `anx7625_typec_set_status':
> anx7625.c:(.text+0x3080): undefined reference to `usb_role_switch_set_role'
> aarch64-linux-ld: drivers/gpu/drm/bridge/analogix/anx7625.o: in function `anx7625_i2c_probe':
> anx7625.c:(.text+0x5368): undefined reference to `fwnode_usb_role_switch_get'
> 
> The problem is that both dependencies are optional in the sense of allowing
> the anx7625 driver to call the exported interfaces to be used from a loadable
> module, but cannot work for built-in drivers. It would be possible to handle
> all nine combinations of the CONFIG_TYPEC and CONFIG_USB_ROLE_SWITCH tristate
> options, but that does add a lot of complexity that seems unnecessary when
> in reality any user of this driver would have both enabled anyway.
> 
> Turn both dependencies into hard 'depends on' here to only allow configurations
> where it's possible to actually use them, and remove the misguided IS_REACHABLE()
> check that did nothing here.
> 
> Fixes: f81455b2d332 ("drm: bridge: anx7625: implement minimal Type-C support")
> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
> ---
>   drivers/gpu/drm/bridge/analogix/Kconfig   |  3 ++-
>   drivers/gpu/drm/bridge/analogix/anx7625.c | 17 -----------------
>   2 files changed, 2 insertions(+), 18 deletions(-)
> 
> diff --git a/drivers/gpu/drm/bridge/analogix/Kconfig b/drivers/gpu/drm/bridge/analogix/Kconfig
> index f3448b0631fe..03dc7ffe824a 100644
> --- a/drivers/gpu/drm/bridge/analogix/Kconfig
> +++ b/drivers/gpu/drm/bridge/analogix/Kconfig
> @@ -34,7 +34,8 @@ config DRM_ANALOGIX_ANX7625
>   	tristate "Analogix Anx7625 MIPI to DP interface support"
>   	depends on DRM
>   	depends on OF
> -	depends on TYPEC || !TYPEC
> +	depends on TYPEC
> +	depends on USB_ROLE_SWITCH
>   	select DRM_DISPLAY_DP_HELPER
>   	select DRM_DISPLAY_HDCP_HELPER
>   	select DRM_DISPLAY_HELPER
> diff --git a/drivers/gpu/drm/bridge/analogix/anx7625.c b/drivers/gpu/drm/bridge/analogix/anx7625.c
> index c43519097a45..ec4b24481987 100644
> --- a/drivers/gpu/drm/bridge/analogix/anx7625.c
> +++ b/drivers/gpu/drm/bridge/analogix/anx7625.c
> @@ -1483,7 +1483,6 @@ static void anx7625_start_dp_work(struct anx7625_data *ctx)
>   	DRM_DEV_DEBUG_DRIVER(dev, "Secure OCM version=%02x\n", ret);
>   }
>   
> -#if IS_REACHABLE(CONFIG_TYPEC)
>   static u8 anx7625_checksum(u8 *buf, u8 len)
>   {
>   	u8 ret = 0;
> @@ -1635,22 +1634,6 @@ static void anx7625_typec_unregister(struct anx7625_data *ctx)
>   	usb_role_switch_put(ctx->role_sw);
>   	typec_unregister_port(ctx->typec_port);
>   }
> -#else
> -static void anx7625_typec_set_status(struct anx7625_data *ctx,
> -				     unsigned int intr_status,
> -				     unsigned int intr_vector)
> -{
> -}
> -
> -static int anx7625_typec_register(struct anx7625_data *ctx)
> -{
> -	return 0;
> -}
> -
> -static void anx7625_typec_unregister(struct anx7625_data *ctx)
> -{
> -}
> -#endif
>   
>   static int anx7625_read_hpd_status_p0(struct anx7625_data *ctx)
>   {

Reviewed-by: Neil Armstrong <neil.armstrong@linaro.org>

Thanks,
Neil