[PATCH v2 3/7] drm/bridge: dw-mipi-dsi: stop using deprecated devm_drm_of_get_bridge()

[Luca Ceresoli]

devm_drm_of_get_bridge() is deprecated, switch to
of_drm_get_bridge_by_endpoint(). As of_drm_get_bridge_by_endpoint() returns
a refcounted bridge, ensure it is put by using bridge.next_bridge.

Fixes build failure when CONFIG_OF is disabled.

Fixes: aa8a8c7e4641 ("drm/bridge: panel: move all code to drm_panel.c")
Reported-by: Arnd Bergmann <arnd at kernel.org>
Closes: https://lore.kernel.org/r/20260928161605.2271412-1-arnd@kernel.org
Reported-by: kernel test robot <lkp at intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202609291109.9RGna4XZ-lkp@intel.com/
Signed-off-by: Luca Ceresoli <luca.ceresoli at bootlin.com>

---

Changes in v2:
- fix bridge reference leak on attach error and detach paths
- mention lkp report
---
 drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c | 11 +++++------
 1 file changed, 5 insertions(+), 6 deletions(-)

diff --git a/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c b/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c
index 5dd475fcaacf..22d1b8cbe1d5 100644
--- a/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c
+++ b/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c
@@ -244,7 +244,6 @@ struct debugfs_entries {
 struct dw_mipi_dsi {
 	struct drm_bridge bridge;
 	struct mipi_dsi_host dsi_host;
-	struct drm_bridge *panel_bridge;
 	struct device *dev;
 	void __iomem *base;
 
@@ -333,12 +332,12 @@ static int dw_mipi_dsi_host_attach(struct mipi_dsi_host *host,
 	dsi->format = device->format;
 	dsi->mode_flags = device->mode_flags;
 
-	bridge = devm_drm_of_get_bridge(dsi->dev, dsi->dev->of_node, 1, 0);
+	bridge = of_drm_get_bridge_by_endpoint(dsi->dev->of_node, 1, 0);
 	if (IS_ERR(bridge))
 		return PTR_ERR(bridge);
 
 	bridge->pre_enable_prev_first = true;
-	dsi->panel_bridge = bridge;
+	dsi->bridge.next_bridge = bridge;
 
 	drm_bridge_add(&dsi->bridge);
 
@@ -352,6 +351,7 @@ static int dw_mipi_dsi_host_attach(struct mipi_dsi_host *host,
 
 err_remove_bridge:
 	drm_bridge_remove(&dsi->bridge);
+	drm_bridge_clear_and_put(&dsi->bridge.next_bridge);
 	return ret;
 }
 
@@ -368,9 +368,8 @@ static int dw_mipi_dsi_host_detach(struct mipi_dsi_host *host,
 			return ret;
 	}
 
-	drm_of_panel_bridge_remove(host->dev->of_node, 1, 0);
-
 	drm_bridge_remove(&dsi->bridge);
+	drm_bridge_clear_and_put(&dsi->bridge.next_bridge);
 
 	return 0;
 }
@@ -1086,7 +1085,7 @@ static int dw_mipi_dsi_bridge_attach(struct drm_bridge *bridge,
 	encoder->encoder_type = DRM_MODE_ENCODER_DSI;
 
 	/* Attach the panel-bridge to the dsi bridge */
-	return drm_bridge_attach(encoder, dsi->panel_bridge, bridge,
+	return drm_bridge_attach(encoder, dsi->bridge.next_bridge, bridge,
 				 flags);
 }
 

-- 
2.55.0