From: Pin-yen Lin treapking@chromium.org
[ Upstream commit e577d4b13064c337b83fe7edecb3f34e87144821 ]
During device boot, the HPD interrupt could be triggered before the DRM subsystem registers it6505 as a DRM bridge. In such cases, the driver tries to access AUX channel and causes NULL pointer dereference. Initializing the AUX channel earlier to prevent such error.
Fixes: b5c84a9edcd4 ("drm/bridge: add it6505 driver") Signed-off-by: Pin-yen Lin treapking@chromium.org Reviewed-by: Robert Foss robert.foss@linaro.org Signed-off-by: Robert Foss robert.foss@linaro.org Link: https://patchwork.freedesktop.org/patch/msgid/20221013110411.1674359-2-treap... Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/gpu/drm/bridge/ite-it6505.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-)
diff --git a/drivers/gpu/drm/bridge/ite-it6505.c b/drivers/gpu/drm/bridge/ite-it6505.c index a09d1a39ab0a..711f403afe7c 100644 --- a/drivers/gpu/drm/bridge/ite-it6505.c +++ b/drivers/gpu/drm/bridge/ite-it6505.c @@ -2854,10 +2854,7 @@ static int it6505_bridge_attach(struct drm_bridge *bridge, }
/* Register aux channel */ - it6505->aux.name = "DP-AUX"; - it6505->aux.dev = dev; it6505->aux.drm_dev = bridge->dev; - it6505->aux.transfer = it6505_aux_transfer;
ret = drm_dp_aux_register(&it6505->aux);
@@ -3310,6 +3307,11 @@ static int it6505_i2c_probe(struct i2c_client *client, DRM_DEV_DEBUG_DRIVER(dev, "it6505 device name: %s", dev_name(dev)); debugfs_init(it6505);
+ it6505->aux.name = "DP-AUX"; + it6505->aux.dev = dev; + it6505->aux.transfer = it6505_aux_transfer; + drm_dp_aux_init(&it6505->aux); + it6505->bridge.funcs = &it6505_bridge_funcs; it6505->bridge.type = DRM_MODE_CONNECTOR_DisplayPort; it6505->bridge.ops = DRM_BRIDGE_OP_DETECT | DRM_BRIDGE_OP_EDID |