[PATCH 07/11] drm/bridge: waveshare-dsi: don't create a panel_bridge

From: Luca Ceresoli

Date: Fri Aug 14 2026 - 10:08:32 EST


Now a panel_bridge is automatically created for every drm_panel, so this
panel-only call to drm_of_find_panel_or_bridge() would lead to creating a
second panel_bridge for the same panel.

Fix and simplify the code by just getting a reference to the
already-existing panel_bridge using of_drm_get_bridge_by_endpoint().

As of_drm_get_bridge_by_endpoint() returns a refcouncted bridge, take care
of putting the bridge reference by using bridge->next_bridge.

Signed-off-by: Luca Ceresoli <luca.ceresoli@xxxxxxxxxxx>
---
drivers/gpu/drm/bridge/waveshare-dsi.c | 16 +++++-----------
1 file changed, 5 insertions(+), 11 deletions(-)

diff --git a/drivers/gpu/drm/bridge/waveshare-dsi.c b/drivers/gpu/drm/bridge/waveshare-dsi.c
index 420f3b870a74..b79a1d32e679 100644
--- a/drivers/gpu/drm/bridge/waveshare-dsi.c
+++ b/drivers/gpu/drm/bridge/waveshare-dsi.c
@@ -20,7 +20,6 @@

struct ws_bridge {
struct drm_bridge bridge;
- struct drm_bridge *next_bridge;
struct backlight_device *backlight;
struct device *dev;
struct regmap *reg_map;
@@ -89,7 +88,7 @@ static int ws_bridge_bridge_attach(struct drm_bridge *bridge,
{
struct ws_bridge *ws = bridge_to_ws_bridge(bridge);

- return drm_bridge_attach(encoder, ws->next_bridge,
+ return drm_bridge_attach(encoder, ws->bridge.next_bridge,
&ws->bridge, flags);
}

@@ -150,7 +149,6 @@ static struct backlight_device *ws_bridge_create_backlight(struct ws_bridge *ws)
static int ws_bridge_probe(struct i2c_client *i2c)
{
struct device *dev = &i2c->dev;
- struct drm_panel *panel;
struct ws_bridge *ws;
int ret;

@@ -164,14 +162,10 @@ static int ws_bridge_probe(struct i2c_client *i2c)
if (IS_ERR(ws->reg_map))
return dev_err_probe(dev, PTR_ERR(ws->reg_map), "Failed to allocate regmap\n");

- ret = drm_of_find_panel_or_bridge(dev->of_node, 1, -1, &panel, NULL);
- if (ret)
- return dev_err_probe(dev, ret, "Failed to find remote panel\n");
-
- ws->next_bridge = devm_drm_panel_bridge_add(dev, panel);
- drm_panel_put(panel);
- if (IS_ERR(ws->next_bridge))
- return PTR_ERR(ws->next_bridge);
+ ws->bridge.next_bridge = of_drm_get_bridge_by_endpoint(dev->of_node, 1, -1);
+ if (IS_ERR(ws->bridge.next_bridge))
+ return dev_err_probe(dev, PTR_ERR(ws->bridge.next_bridge),
+ "Failed to find remote panel\n");

ws->backlight = ws_bridge_create_backlight(ws);
if (IS_ERR(ws->backlight)) {

--
2.55.0