[PATCH v7 02/10] drm/vc4: hdmi: Fix HPD GPIO detection

Maxime Ripard maxime at cerno.tech
Thu Aug 19 09:51:11 UTC 2021


Prior to commit 6800234ceee0 ("drm/vc4: hdmi: Convert to gpiod"), in the
detect hook, if we had an HPD GPIO we would only rely on it and return
whatever state it was in.

However, that commit changed that by mistake to only consider the case
where we have a GPIO and it returns a logical high, and would fall back
to the other methods otherwise.

Since we can read the EDIDs when the HPD signal is low on some displays,
we changed the detection status from disconnected to connected, and we
would ignore an HPD pulse.

Fixes: 6800234ceee0 ("drm/vc4: hdmi: Convert to gpiod")
Signed-off-by: Maxime Ripard <maxime at cerno.tech>
---
 drivers/gpu/drm/vc4/vc4_hdmi.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/vc4/vc4_hdmi.c b/drivers/gpu/drm/vc4/vc4_hdmi.c
index f9a672a641ab..251dfecf1d4c 100644
--- a/drivers/gpu/drm/vc4/vc4_hdmi.c
+++ b/drivers/gpu/drm/vc4/vc4_hdmi.c
@@ -169,9 +169,9 @@ vc4_hdmi_connector_detect(struct drm_connector *connector, bool force)
 
 	WARN_ON(pm_runtime_resume_and_get(&vc4_hdmi->pdev->dev));
 
-	if (vc4_hdmi->hpd_gpio &&
-	    gpiod_get_value_cansleep(vc4_hdmi->hpd_gpio)) {
-		connected = true;
+	if (vc4_hdmi->hpd_gpio) {
+		if (gpiod_get_value_cansleep(vc4_hdmi->hpd_gpio))
+			connected = true;
 	} else if (HDMI_READ(HDMI_HOTPLUG) & VC4_HDMI_HOTPLUG_CONNECTED) {
 		connected = true;
 	}
-- 
2.31.1



More information about the dri-devel mailing list