Re: [PATCH] drm/bridge_connector: enable HPD by default if supported

From: Paul Cercueil
Date: Fri Mar 04 2022 - 15:01:09 EST


Hi Nikita,

Le sam., déc. 25 2021 at 09:31:51 +0300, Nikita Yushchenko <nikita.yoush@xxxxxxxxxxxxxxxxxx> a écrit :
Hotplug events reported by bridge drivers over drm_bridge_hpd_notify()
get ignored unless somebody calls drm_bridge_hpd_enable(). When the
connector for the bridge is bridge_connector, such a call is done from
drm_bridge_connector_enable_hpd().

However drm_bridge_connector_enable_hpd() is never called on init paths,
documentation suggests that it is intended for suspend/resume paths.

In result, once encoders are switched to bridge_connector,
bridge-detected HPD stops working.

This patch adds a call to that API on init path.

This fixes HDMI HPD with rcar-du + adv7513 case when adv7513 reports HPD
events via interrupts.

Fixes: c24110a8fd09 ("drm: rcar-du: Use drm_bridge_connector_init() helper")
Signed-off-by: Nikita Yushchenko <nikita.yoush@xxxxxxxxxxxxxxxxxx>

Merged to drm-misc-next.

Thanks!

Cheers,
-Paul

---
drivers/gpu/drm/drm_bridge_connector.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/drm_bridge_connector.c b/drivers/gpu/drm/drm_bridge_connector.c
index 791379816837..4f20137ef21d 100644
--- a/drivers/gpu/drm/drm_bridge_connector.c
+++ b/drivers/gpu/drm/drm_bridge_connector.c
@@ -369,8 +369,10 @@ struct drm_connector *drm_bridge_connector_init(struct drm_device *drm,
connector_type, ddc);
drm_connector_helper_add(connector, &drm_bridge_connector_helper_funcs);

- if (bridge_connector->bridge_hpd)
+ if (bridge_connector->bridge_hpd) {
connector->polled = DRM_CONNECTOR_POLL_HPD;
+ drm_bridge_connector_enable_hpd(connector);
+ }
else if (bridge_connector->bridge_detect)
connector->polled = DRM_CONNECTOR_POLL_CONNECT
| DRM_CONNECTOR_POLL_DISCONNECT;
--
2.30.2