[PATCH v2] drm/bridge: adv7511: make it honour next bridge in DT

[Dmitry Baryshkov]

DT bindings for adv7511 and adv7533 bridges specify HDMI output to be
present at the port at 1. This allows board DT to add e.g. HDMI connector
nodes or any other next chained bridge. Make adv7511 driver discover
that bridge and attach it to the chain.

Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov at linaro.org>
---
Changes in v2:
- Fixed the absent next bridge usecase
- Link to v1: https://lore.kernel.org/r/20240309-adv7511-next-bridge-v1-1-d1ad522ef623@linaro.org
---
 drivers/gpu/drm/bridge/adv7511/adv7511.h     |  1 +
 drivers/gpu/drm/bridge/adv7511/adv7511_drv.c | 12 ++++++++++++
 2 files changed, 13 insertions(+)

diff --git a/drivers/gpu/drm/bridge/adv7511/adv7511.h b/drivers/gpu/drm/bridge/adv7511/adv7511.h
index 39c9ece373b0..ea271f62b214 100644
--- a/drivers/gpu/drm/bridge/adv7511/adv7511.h
+++ b/drivers/gpu/drm/bridge/adv7511/adv7511.h
@@ -356,6 +356,7 @@ struct adv7511 {
 	enum drm_connector_status status;
 	bool powered;
 
+	struct drm_bridge *next_bridge;
 	struct drm_display_mode curr_mode;
 
 	unsigned int f_tmds;
diff --git a/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c b/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c
index b5518ff97165..c50d994a33b5 100644
--- a/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c
+++ b/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c
@@ -17,6 +17,7 @@
 #include <drm/drm_atomic.h>
 #include <drm/drm_atomic_helper.h>
 #include <drm/drm_edid.h>
+#include <drm/drm_of.h>
 #include <drm/drm_print.h>
 #include <drm/drm_probe_helper.h>
 
@@ -946,6 +947,12 @@ static int adv7511_bridge_attach(struct drm_bridge *bridge,
 	struct adv7511 *adv = bridge_to_adv7511(bridge);
 	int ret = 0;
 
+	if (adv->next_bridge) {
+		ret = drm_bridge_attach(bridge->encoder, adv->next_bridge, bridge, flags);
+		if (ret)
+			return ret;
+	}
+
 	if (!(flags & DRM_BRIDGE_ATTACH_NO_CONNECTOR)) {
 		ret = adv7511_connector_init(adv);
 		if (ret < 0)
@@ -1216,6 +1223,11 @@ static int adv7511_probe(struct i2c_client *i2c)
 
 	memset(&link_config, 0, sizeof(link_config));
 
+	ret = drm_of_find_panel_or_bridge(dev->of_node, 1, -1, NULL,
+					  &adv7511->next_bridge);
+	if (ret && ret != -ENODEV)
+		return ret;
+
 	if (adv7511->info->link_config)
 		ret = adv7511_parse_dt(dev->of_node, &link_config);
 	else

---
base-commit: 1843e16d2df9d98427ef8045589571749d627cf7
change-id: 20240309-adv7511-next-bridge-10d8bbe0544e

Best regards,
-- 
Dmitry Baryshkov <dmitry.baryshkov at linaro.org>