From: Nícolas F. R. A. Prado nfraprado@collabora.com
[ 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@collabora.com Reviewed-by: AngeloGioacchino Del Regno angelogioacchino.delregno@collabora.com Signed-off-by: Robert Foss robert.foss@linaro.org Link: https://patchwork.freedesktop.org/patch/msgid/20220613163705.1531721-1-nfrap... Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/gpu/drm/bridge/analogix/anx7625.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-)
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); }