From deae1e6365cd5b32415dc5b4f8ee22f7c0fa4ae3 Mon Sep 17 00:00:00 2001 From: Imre Deak Date: Mon, 1 Feb 2021 14:01:42 +0200 Subject: [PATCH] drm/dp_mst: Don't report ports connected if nothing is attached to them commit 873e5bb9fbd99e4a26c448b5c7af942a6d7aa60d upstream. Reporting a port as connected if nothing is attached to them leads to any i2c transactions on this port trying to use an uninitialized i2c adapter, fix this. Let's account for this case even if branch devices have no good reason to report a port as plugged with their peer device type set to 'none'. Fixes: db1a07956968 ("drm/dp_mst: Handle SST-only branch device case") References: https://gitlab.freedesktop.org/drm/intel/-/issues/2987 References: https://gitlab.freedesktop.org/drm/intel/-/issues/1963 Cc: Wayne Lin Cc: Lyude Paul Cc: # v5.5+ Cc: intel-gfx@lists.freedesktop.org Signed-off-by: Imre Deak Reviewed-by: Lyude Paul Reported-by: Thiago Macieira Link: https://patchwork.freedesktop.org/patch/msgid/20210201120145.350258-1-imre.deak@intel.com Signed-off-by: Greg Kroah-Hartman --- drivers/gpu/drm/drm_dp_mst_topology.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/gpu/drm/drm_dp_mst_topology.c b/drivers/gpu/drm/drm_dp_mst_topology.c index 7749b0ceabba9..17bdad95978a1 100644 --- a/drivers/gpu/drm/drm_dp_mst_topology.c +++ b/drivers/gpu/drm/drm_dp_mst_topology.c @@ -4224,6 +4224,7 @@ drm_dp_mst_detect_port(struct drm_connector *connector, switch (port->pdt) { case DP_PEER_DEVICE_NONE: + break; case DP_PEER_DEVICE_MST_BRANCHING: if (!port->mcs) ret = connector_status_connected;