On Tue, Jan 4, 2022 at 3:30 PM AngeloGioacchino Del Regno <angelogioacchino.delregno@xxxxxxxxxxxxx> wrote: > > DRM bridge drivers are now attaching their DSI device at probe time, > which requires us to register our DSI host in order to let the bridge > to probe: this recently started producing an endless -EPROBE_DEFER > loop on some machines that are using external bridges, like the > parade-ps8640, found on the ACER Chromebook R13. > > Now that the DSI hosts/devices probe sequence is documented, we can > do adjustments to the mtk_dsi driver as to both fix now and make sure > to avoid this situation in the future: for this, following what is > documented in drm_bridge.c, move the mtk_dsi component_add() to the > mtk_dsi_ops.attach callback and delete it in the detach callback; > keeping in mind that we are registering a drm_bridge for our DSI, > which is only used/attached if the DSI Host is bound, it wouldn't > make sense to keep adding our bridge at probe time (as it would > be useless to have it if mtk_dsi_ops.attach() fails!), so also move > that one to the dsi host attach function (and remove it in detach). > > Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@xxxxxxxxxxxxx> > Reviewed-by: Andrzej Hajda <andrzej.hajda@xxxxxxxxx> > --- Eventually I've observed similar issue on other Component based DSI controllers, hence Reviewed-by: Jagan Teki <jagan@xxxxxxxxxxxxxxxxxxxx>
