diff options
| author |   Brian Norris <briannorris@chromium.org> | 2022-03-01 18:11:38 -0800 |
|---|---|---|
| committer |   Douglas Anderson <dianders@chromium.org> | 2022-03-09 08:00:39 -0800 |
| commit | 8fb6c44fe8468f92ac7b8bbfcca4404a4e88645f (patch) | |
| tree | dc86069e4d0dedbc3723b9b01a938400592ff201 | |
| parent | drm/bridge: Add myself as a reviewer for the Parade PS8640 bridge chip (diff) | |
| download | linux-dev-8fb6c44fe8468f92ac7b8bbfcca4404a4e88645f.tar.xz linux-dev-8fb6c44fe8468f92ac7b8bbfcca4404a4e88645f.zip | |
drm/bridge: analogix_dp: Grab runtime PM reference for DP-AUX
If the display is not enable()d, then we aren't holding a runtime PM
reference here. Thus, it's easy to accidentally cause a hang, if user
space is poking around at /dev/drm_dp_aux0 at the "wrong" time.
Let's get a runtime PM reference, and check that we "see" the panel.
Don't force any panel power-up, etc., because that can be intrusive, and
that's not what other drivers do (see
drivers/gpu/drm/bridge/ti-sn65dsi86.c and
drivers/gpu/drm/bridge/parade-ps8640.c.)
Fixes: 0d97ad03f422 ("drm/bridge: analogix_dp: Remove duplicated code")
Cc: <stable@vger.kernel.org>
Cc: Tomeu Vizoso <tomeu.vizoso@collabora.com>
Signed-off-by: Brian Norris <briannorris@chromium.org>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20220301181107.v4.1.I773a08785666ebb236917b0c8e6c05e3de471e75@changeid
| -rw-r--r-- | drivers/gpu/drm/bridge/analogix/analogix_dp_core.c | 13 |
1 files changed, 12 insertions, 1 deletions
diff --git a/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c b/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c index eb590fb8e8d0..d45931913dfc 100644 --- a/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c +++ b/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c @@ -1632,8 +1632,19 @@ static ssize_t analogix_dpaux_transfer(struct drm_dp_aux *aux, struct drm_dp_aux_msg *msg) { struct analogix_dp_device *dp = to_dp(aux); + int ret; + + pm_runtime_get_sync(dp->dev); + + ret = analogix_dp_detect_hpd(dp); + if (ret) + goto out; - return analogix_dp_transfer(dp, msg); + ret = analogix_dp_transfer(dp, msg); +out: + pm_runtime_put(dp->dev); + + return ret; } struct analogix_dp_device * |