Patch "drm/bridge: anx7625: Zero error variable when panel bridge not present" has been added to the 5.19-stable tree

[Sasha Levin <sashal@xxxxxxxxxx>]

This is a note to let you know that I've just added the patch titled

    drm/bridge: anx7625: Zero error variable when panel bridge not present

to the 5.19-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     drm-bridge-anx7625-zero-error-variable-when-panel-br.patch
and it can be found in the queue-5.19 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.



commit e2742e2a5bf765f0168f772b8d31497f19679ca1
Author: Nícolas F. R. A. Prado <nfraprado@xxxxxxxxxxxxx>
Date:   Mon Jun 13 12:37:05 2022 -0400

    drm/bridge: anx7625: Zero error variable when panel bridge not present
    
    [ Upstream commit 3f49f7591e7150c502aa8d04354941ec2394153f ]
    
    While parsing the DT, the anx7625 driver checks for the presence of a
    panel bridge on endpoint 1. If it is missing, pdata->panel_bridge stores
    the error pointer and the function returns successfully without first
    cleaning that variable. This is an issue since other functions later
    check for the presence of a panel bridge by testing the trueness of that
    variable.
    
    In order to ensure proper behavior, zero out pdata->panel_bridge before
    returning when no panel bridge is found.
    
    Fixes: 9e82ea0fb1df ("drm/bridge: anx7625: switch to devm_drm_of_get_bridge")
    Signed-off-by: Nícolas F. R. A. Prado <nfraprado@xxxxxxxxxxxxx>
    Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@xxxxxxxxxxxxx>
    Signed-off-by: Robert Foss <robert.foss@xxxxxxxxxx>
    Link: https://patchwork.freedesktop.org/patch/msgid/20220613163705.1531721-1-nfraprado@xxxxxxxxxxxxx
    Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>

diff --git a/drivers/gpu/drm/bridge/analogix/anx7625.c b/drivers/gpu/drm/bridge/analogix/anx7625.c
index 01f46d9189c1..0117fd8c62ae 100644
--- a/drivers/gpu/drm/bridge/analogix/anx7625.c
+++ b/drivers/gpu/drm/bridge/analogix/anx7625.c
@@ -1657,8 +1657,10 @@ static int anx7625_parse_dt(struct device *dev,
 
 	pdata->panel_bridge = devm_drm_of_get_bridge(dev, np, 1, 0);
 	if (IS_ERR(pdata->panel_bridge)) {
-		if (PTR_ERR(pdata->panel_bridge) == -ENODEV)
+		if (PTR_ERR(pdata->panel_bridge) == -ENODEV) {
+			pdata->panel_bridge = NULL;
 			return 0;
+		}
 
 		return PTR_ERR(pdata->panel_bridge);
 	}