[PATCH v2] drm/bridge: sii902x: Fix HDMI detection with DRM_BRIDGE_ATTACH_NO_CONNECTOR

From: Devarsh Thakkar

Date: Mon Oct 06 2025 - 11:08:20 EST


The SII902x HDMI bridge driver wasn't working properly with drivers that
use the newer bridge connector architecture with the
DRM_BRIDGE_ATTACH_NO_CONNECTOR flag, like TIDSS. This caused HDMI audio to
fail since the driver wasn't properly setting the sink_is_hdmi flag when
the bridge was attached without a connector since .get_modes() is never
called in this case. Fix it by setting sink_is_hdmi flag when reading
the EDID block itself.

Fixes: 3de47e1309c2 ("drm/bridge: sii902x: use display info is_hdmi")
Signed-off-by: Devarsh Thakkar <devarsht@xxxxxx>
---
V2: Use drm_edid_connector_update to detect HDMI as suggested

Link to V1:
https://lore.kernel.org/all/20251003143642.4072918-1-devarsht@xxxxxx/
---
drivers/gpu/drm/bridge/sii902x.c | 7 ++++---
1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/bridge/sii902x.c b/drivers/gpu/drm/bridge/sii902x.c
index d537b1d036fb..d36466d73385 100644
--- a/drivers/gpu/drm/bridge/sii902x.c
+++ b/drivers/gpu/drm/bridge/sii902x.c
@@ -296,6 +296,10 @@ static const struct drm_edid *sii902x_edid_read(struct sii902x *sii902x,
mutex_lock(&sii902x->mutex);

drm_edid = drm_edid_read_ddc(connector, sii902x->i2cmux->adapter[0]);
+ if (drm_edid) {
+ drm_edid_connector_update(connector, drm_edid);
+ sii902x->sink_is_hdmi = connector->display_info.is_hdmi;
+ }

mutex_unlock(&sii902x->mutex);

@@ -309,14 +313,11 @@ static int sii902x_get_modes(struct drm_connector *connector)
int num = 0;

drm_edid = sii902x_edid_read(sii902x, connector);
- drm_edid_connector_update(connector, drm_edid);
if (drm_edid) {
num = drm_edid_connector_add_modes(connector);
drm_edid_free(drm_edid);
}

- sii902x->sink_is_hdmi = connector->display_info.is_hdmi;
-
return num;
}

--
2.39.1