On Fri, Oct 18, 2024 at 03:08:45PM +0000, Arnd Bergmann wrote:
> From: Arnd Bergmann <arnd@xxxxxxxx>
>
> The imx display drivers use the new bridge connector helpers but don't
> explicitly select CONFIG_DRM_DISPLAY_HELPER, leading to a link failure
> in rare configurations:
>
> ld.lld-20: error: undefined symbol: drm_bridge_connector_init
> >>> referenced by imx-ldb.c
> >>> drivers/gpu/drm/imx/ipuv3/imx-ldb.o:(imx_ldb_bind) in archive vmlinux.a
> >>> referenced by parallel-display.c
> >>> drivers/gpu/drm/imx/ipuv3/parallel-display.o:(imx_pd_bind) in archive vmlinux.a
>
> Move DRM_BRIDGE_CONNECTOR out of the DRM_DISPLAY_HELPER block and
> instead select that symbol indirectly.
>
> Fixes: f94b9707a1c9 ("drm/imx: parallel-display: switch to imx_legacy_bridge / drm_bridge_connector")
> Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>
I think a correct fix is to select DRM_DISPLAY_HELPER instead.
> ---
> drivers/gpu/drm/display/Kconfig | 5 +++--
> 1 file changed, 3 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/gpu/drm/display/Kconfig b/drivers/gpu/drm/display/Kconfig
> index 0f07cf1483ff..beb05d9bab50 100644
> --- a/drivers/gpu/drm/display/Kconfig
> +++ b/drivers/gpu/drm/display/Kconfig
> @@ -11,14 +11,15 @@ config DRM_DISPLAY_HELPER
> help
> DRM helpers for display adapters.
>
> -if DRM_DISPLAY_HELPER
> -
> config DRM_BRIDGE_CONNECTOR
> bool
> select DRM_DISPLAY_HDMI_STATE_HELPER
> + select DRM_DISPLAY_HELPER
> help
> DRM connector implementation terminating DRM bridge chains.
>
> +if DRM_DISPLAY_HELPER
> +
> config DRM_DISPLAY_DP_AUX_CEC
> bool "Enable DisplayPort CEC-Tunneling-over-AUX HDMI support"
> select DRM_DISPLAY_DP_HELPER
> --
> 2.39.5
>
--
With best wishes
Dmitry
