Re: [Intel-gfx] [PATCH] Revert "drm/i915/mst: Populate connector->ddc"

[Jani Nikula <jani.nikula@linux.intel.com>]

On Tue, 19 Sep 2023, Ville Syrjala <ville.syrjala@linux.intel.com> wrote:
> From: Ville Syrjälä <ville.syrjala@linux.intel.com>
>
> This reverts commit 959fb1a686528df1b8fb0cc7bec8ff851b1594a5.
>
> Looks like the core MST code might not call i2c_adapter() for us
> in time, and thus creating the ddc symlink will fail. This will
> in fact fail the entire connector registration, but the MST code
> doesn't really seem to care about that and blindly plows ahead.
> All we may get in the logs is a nearly back to back
> register+unregister debug messages:
>  [drm:drm_dp_mst_connector_late_register [drm_display_helper]] registering DPMST remote bus for card0-DP-7
>  [drm:intel_dp_hpd_pulse [i915]] DPRX ESI: 42 00 00 02
>  [drm:drm_dp_mst_connector_early_unregister [drm_display_helper]] unregistering DPMST remote bus for card0-DP-7
>
> Untangling the initialization order may take some real work,
> so let's just revert the ddc symlink addition for now...
>
> Closes: https://gitlab.freedesktop.org/drm/intel/-/issues/9357
> Fixes: 959fb1a68652 ("drm/i915/mst: Populate connector->ddc")
> Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>

Acked-by: Jani Nikula <jani.nikula@intel.com>

> ---
>  drivers/gpu/drm/i915/display/intel_dp_mst.c | 6 ++----
>  1 file changed, 2 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/display/intel_dp_mst.c b/drivers/gpu/drm/i915/display/intel_dp_mst.c
> index 80411ce85fc0..ff3accebf0a8 100644
> --- a/drivers/gpu/drm/i915/display/intel_dp_mst.c
> +++ b/drivers/gpu/drm/i915/display/intel_dp_mst.c
> @@ -1110,10 +1110,8 @@ static struct drm_connector *intel_dp_add_mst_connector(struct drm_dp_mst_topolo
>  	drm_dp_mst_get_port_malloc(port);
>  
>  	connector = &intel_connector->base;
> -	ret = drm_connector_init_with_ddc(dev, connector,
> -					  &intel_dp_mst_connector_funcs,
> -					  DRM_MODE_CONNECTOR_DisplayPort,
> -					  &port->aux.ddc);
> +	ret = drm_connector_init(dev, connector, &intel_dp_mst_connector_funcs,
> +				 DRM_MODE_CONNECTOR_DisplayPort);
>  	if (ret) {
>  		drm_dp_mst_put_port_malloc(port);
>  		intel_connector_free(intel_connector);

-- 
Jani Nikula, Intel