This is a note to let you know that I've just added the patch titled
drm/vc4: hdmi: Make sure the controller is powered in detect
to the 5.12-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-vc4-hdmi-make-sure-the-controller-is-powered-in-.patch
and it can be found in the queue-5.12 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 955d4445d923c48b8cdd0263a6998f4d767dd84f
Author: Maxime Ripard <maxime@xxxxxxxxxx>
Date: Tue May 25 11:10:59 2021 +0200
drm/vc4: hdmi: Make sure the controller is powered in detect
[ Upstream commit 9984d6664ce9dcbbc713962539eaf7636ea246c2 ]
If the HPD GPIO is not available and drm_probe_ddc fails, we end up
reading the HDMI_HOTPLUG register, but the controller might be powered
off resulting in a CPU hang. Make sure we have the power domain and the
HSM clock powered during the detect cycle to prevent the hang from
happening.
Fixes: 4f6e3d66ac52 ("drm/vc4: Add runtime PM support to the HDMI encoder driver")
Signed-off-by: Maxime Ripard <maxime@xxxxxxxxxx>
Reviewed-by: Dave Stevenson <dave.stevenson@xxxxxxxxxxxxxxx>
Link: https://patchwork.freedesktop.org/patch/msgid/20210525091059.234116-4-maxime@xxxxxxxxxx
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/gpu/drm/vc4/vc4_hdmi.c b/drivers/gpu/drm/vc4/vc4_hdmi.c
index 84e218365045..8106b5634fe1 100644
--- a/drivers/gpu/drm/vc4/vc4_hdmi.c
+++ b/drivers/gpu/drm/vc4/vc4_hdmi.c
@@ -159,6 +159,8 @@ vc4_hdmi_connector_detect(struct drm_connector *connector, bool force)
struct vc4_hdmi *vc4_hdmi = connector_to_vc4_hdmi(connector);
bool connected = false;
+ WARN_ON(pm_runtime_resume_and_get(&vc4_hdmi->pdev->dev));
+
if (vc4_hdmi->hpd_gpio) {
if (gpio_get_value_cansleep(vc4_hdmi->hpd_gpio) ^
vc4_hdmi->hpd_active_low)
@@ -180,10 +182,12 @@ vc4_hdmi_connector_detect(struct drm_connector *connector, bool force)
}
}
+ pm_runtime_put(&vc4_hdmi->pdev->dev);
return connector_status_connected;
}
cec_phys_addr_invalidate(vc4_hdmi->cec_adap);
+ pm_runtime_put(&vc4_hdmi->pdev->dev);
return connector_status_disconnected;
}
