On 18.06.2018 12:28, Heiko Stuebner wrote: > When the panel-driver is build as a module it currently fails hard as the > panel cannot be probed directly: > > dw_mipi_dsi_bind() > __dw_mipi_dsi_probe() > creates dsi bus > creates panel device > triggers panel module load > panel not probed (module not loaded or panel probe slow) > drm_bridge_attach > fails with -EINVAL due to empty panel_bridge > > So emit a -EPROBE_DEFER in that case to give the driver another > chance at getting the display later.
Thats odd (at least for me), if the resource (panel in this case) is not present, bridge should not be attached (drm_bridge_attach should not be called). Ie __dw_mipi_dsi_probe should rather look for the panel and defer if not found. Resource gathering is the task of probe. drm_bridge_attach can be called after probe and it would be difficult for the caller to react properly for -EPROBE_DEFER error. Regards Andrzej > > Signed-off-by: Heiko Stuebner <he...@sntech.de> > --- > drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c | 3 +++ > 1 file changed, 3 insertions(+) > > diff --git a/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c > b/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c > index bb4aeca5c0f9..bd503f000ed5 100644 > --- a/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c > +++ b/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c > @@ -835,6 +835,9 @@ static int dw_mipi_dsi_bridge_attach(struct drm_bridge > *bridge) > return -ENODEV; > } > > + if (!dsi->panel_bridge) > + return -EPROBE_DEFER; > + > /* Set the encoder type as caller does not know it */ > bridge->encoder->encoder_type = DRM_MODE_ENCODER_DSI; > _______________________________________________ dri-devel mailing list dri-devel@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/dri-devel
