Unverified Commit 9984d666 authored by Maxime Ripard's avatar Maxime Ripard
Browse files

drm/vc4: hdmi: Make sure the controller is powered in detect 



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: 4f6e3d66 ("drm/vc4: Add runtime PM support to the HDMI encoder driver")
Signed-off-by: default avatarMaxime Ripard <maxime@cerno.tech>
Reviewed-by: default avatarDave Stevenson <dave.stevenson@raspberrypi.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210525091059.234116-4-maxime@cerno.tech
parent 411efa18

drivers/gpu/drm/vc4/vc4_hdmi.c

+4 −0
Original line number Diff line number Diff line
@@ -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;

}