[PATCH RFC v2 01/19] drm: of: move drm_of_find_panel_or_bridge() from drm_of.c to bridge/panel.c
From: Luca Ceresoli
Date: Thu Sep 03 2026 - 04:34:20 EST
We want to move drm_panel.o from the main drm module to a new drm_panel
module, but there is one function in the drm module that calls into
drm_panel.c code:
drm_of_find_panel_or_bridge() (in drm_of.c, drm module)
-> calls of_drm_find_panel (in drm_panel.c, would-be the new drm_panel module)
Avoid this issue by moving drm_of_find_panel_or_bridge() to bridge/panel.c
(which is currently in the drm_kms_helper module).
As a result drm_kms_helper will depend on the new drm_panel module, which
is fine because there is no dependency of drm_panel on drm_kms_helper.
After this change, all drivers using drm_of_find_panel_or_bridge() will
have to select DRM_PANEL_BRIDGE (and DRM_PANEL, recursively). Add that for
affected drivers. While there, also add DRM_PANEL on drivers selecting
DRM_PANEL_BRIDGE.
No functional changes, just moving code around.
[AI used to add 'select DRM_PANEL[_BRIDGE]' for affected drivers]
Assisted-by: opencode:deepseek-v4-flash-0731
Signed-off-by: Luca Ceresoli <luca.ceresoli@xxxxxxxxxxx>
---
drivers/gpu/drm/bridge/Kconfig | 2 ++
drivers/gpu/drm/bridge/analogix/Kconfig | 4 +++
drivers/gpu/drm/bridge/panel.c | 63 +++++++++++++++++++++++++++++++++
drivers/gpu/drm/drm_of.c | 63 ---------------------------------
drivers/gpu/drm/fsl-dcu/Kconfig | 1 +
drivers/gpu/drm/imx/dcss/Kconfig | 2 ++
drivers/gpu/drm/ingenic/Kconfig | 1 +
drivers/gpu/drm/logicvc/Kconfig | 2 ++
drivers/gpu/drm/mcde/Kconfig | 1 +
drivers/gpu/drm/pl111/Kconfig | 1 +
drivers/gpu/drm/renesas/rcar-du/Kconfig | 1 +
drivers/gpu/drm/rockchip/Kconfig | 4 +++
drivers/gpu/drm/stm/Kconfig | 1 +
drivers/gpu/drm/sun4i/Kconfig | 1 +
drivers/gpu/drm/tegra/Kconfig | 1 +
drivers/gpu/drm/tidss/Kconfig | 2 ++
drivers/gpu/drm/tve200/Kconfig | 1 +
include/drm/drm_bridge.h | 12 +++++++
include/drm/drm_of.h | 12 -------
19 files changed, 100 insertions(+), 75 deletions(-)
diff --git a/drivers/gpu/drm/bridge/Kconfig b/drivers/gpu/drm/bridge/Kconfig
index f2db7f60d40f..89e87460aefc 100644
--- a/drivers/gpu/drm/bridge/Kconfig
+++ b/drivers/gpu/drm/bridge/Kconfig
@@ -151,6 +151,7 @@ config DRM_LONTIUM_LT8912B
config DRM_LONTIUM_LT9211
tristate "Lontium LT9211 DSI/LVDS/DPI bridge"
depends on OF
+ select DRM_PANEL
select DRM_PANEL_BRIDGE
select DRM_KMS_HELPER
select DRM_MIPI_DSI
@@ -498,6 +499,7 @@ config DRM_WAVESHARE_BRIDGE
tristate "Waveshare DSI bridge"
depends on OF
depends on BACKLIGHT_CLASS_DEVICE
+ select DRM_PANEL
select DRM_PANEL_BRIDGE
select DRM_KMS_HELPER
select DRM_MIPI_DSI
diff --git a/drivers/gpu/drm/bridge/analogix/Kconfig b/drivers/gpu/drm/bridge/analogix/Kconfig
index 57bb2daa5aaf..d07431788fcb 100644
--- a/drivers/gpu/drm/bridge/analogix/Kconfig
+++ b/drivers/gpu/drm/bridge/analogix/Kconfig
@@ -6,6 +6,8 @@ config DRM_ANALOGIX_ANX6345
select DRM_DISPLAY_DP_HELPER
select DRM_DISPLAY_HELPER
select DRM_KMS_HELPER
+ select DRM_PANEL
+ select DRM_PANEL_BRIDGE
select REGMAP_I2C
help
ANX6345 is an ultra-low power Full-HD DisplayPort/eDP
@@ -32,6 +34,8 @@ config DRM_ANALOGIX_DP
depends on DRM
depends on OF
select DRM_DISPLAY_DP_AUX_BUS
+ select DRM_PANEL
+ select DRM_PANEL_BRIDGE
config DRM_ANALOGIX_ANX7625
tristate "Analogix Anx7625 MIPI to DP interface support"
diff --git a/drivers/gpu/drm/bridge/panel.c b/drivers/gpu/drm/bridge/panel.c
index 02388a3de626..83be09641582 100644
--- a/drivers/gpu/drm/bridge/panel.c
+++ b/drivers/gpu/drm/bridge/panel.c
@@ -560,4 +560,67 @@ struct drm_bridge *drmm_of_get_bridge(struct drm_device *drm,
}
EXPORT_SYMBOL(drmm_of_get_bridge);
+/**
+ * drm_of_find_panel_or_bridge - return connected panel or bridge device
+ * @np: device tree node containing encoder output ports
+ * @port: port in the device tree node
+ * @endpoint: endpoint in the device tree node
+ * @panel: pointer to hold returned drm_panel, must not be NULL. On success
+ * the caller must call drm_panel_put() when done with the panel
+ * @bridge: pointer to hold returned drm_bridge
+ *
+ * Given a DT node's port and endpoint number, find the connected node and
+ * return either the associated struct drm_panel or drm_bridge device.
+ *
+ * This function is deprecated and should not be used in new drivers. Use
+ * of_drm_get_bridge_by_endpoint() instead when not looking for a panel, or
+ * devm_drm_of_get_bridge() otherwise.
+ *
+ * Returns zero if successful, or one of the standard error codes if it fails.
+ */
+int drm_of_find_panel_or_bridge(const struct device_node *np,
+ int port, int endpoint,
+ struct drm_panel **panel,
+ struct drm_bridge **bridge)
+{
+ if (WARN_ON(!panel))
+ return -EINVAL;
+
+ *panel = NULL;
+ if (bridge)
+ *bridge = NULL;
+
+ /*
+ * of_graph_get_remote_node() produces a noisy error message if port
+ * node isn't found and the absence of the port is a legit case here,
+ * so at first we silently check whether a graph is present in the
+ * device-tree node.
+ */
+ if (!of_graph_is_present(np))
+ return -ENODEV;
+
+ struct device_node *remote __free(device_node) =
+ of_graph_get_remote_node(np, port, endpoint);
+ if (!remote)
+ return -ENODEV;
+
+ *panel = of_drm_find_panel(remote);
+ if (!IS_ERR(*panel))
+ return 0;
+
+ *panel = NULL;
+
+ if (bridge) {
+ /* No panel found yet, check for a bridge next. */
+ *bridge = of_drm_find_bridge(remote);
+ if (*bridge)
+ return 0;
+
+ *bridge = NULL;
+ }
+
+ return -EPROBE_DEFER;
+}
+EXPORT_SYMBOL_GPL(drm_of_find_panel_or_bridge);
+
#endif
diff --git a/drivers/gpu/drm/drm_of.c b/drivers/gpu/drm/drm_of.c
index 2b53124ded68..411f258d9f91 100644
--- a/drivers/gpu/drm/drm_of.c
+++ b/drivers/gpu/drm/drm_of.c
@@ -264,69 +264,6 @@ int drm_of_get_panel_orientation(const struct device_node *np,
}
EXPORT_SYMBOL_GPL(drm_of_get_panel_orientation);
-/**
- * drm_of_find_panel_or_bridge - return connected panel or bridge device
- * @np: device tree node containing encoder output ports
- * @port: port in the device tree node
- * @endpoint: endpoint in the device tree node
- * @panel: pointer to hold returned drm_panel, must not be NULL. On success
- * the caller must call drm_panel_put() when done with the panel
- * @bridge: pointer to hold returned drm_bridge
- *
- * Given a DT node's port and endpoint number, find the connected node and
- * return either the associated struct drm_panel or drm_bridge device.
- *
- * This function is deprecated and should not be used in new drivers. Use
- * of_drm_get_bridge_by_endpoint() instead when not looking for a panel, or
- * devm_drm_of_get_bridge() otherwise.
- *
- * Returns zero if successful, or one of the standard error codes if it fails.
- */
-int drm_of_find_panel_or_bridge(const struct device_node *np,
- int port, int endpoint,
- struct drm_panel **panel,
- struct drm_bridge **bridge)
-{
- if (WARN_ON(!panel))
- return -EINVAL;
-
- *panel = NULL;
- if (bridge)
- *bridge = NULL;
-
- /*
- * of_graph_get_remote_node() produces a noisy error message if port
- * node isn't found and the absence of the port is a legit case here,
- * so at first we silently check whether a graph is present in the
- * device-tree node.
- */
- if (!of_graph_is_present(np))
- return -ENODEV;
-
- struct device_node *remote __free(device_node) =
- of_graph_get_remote_node(np, port, endpoint);
- if (!remote)
- return -ENODEV;
-
- *panel = of_drm_find_panel(remote);
- if (!IS_ERR(*panel))
- return 0;
-
- *panel = NULL;
-
- if (bridge) {
- /* No panel found yet, check for a bridge next. */
- *bridge = of_drm_find_bridge(remote);
- if (*bridge)
- return 0;
-
- *bridge = NULL;
- }
-
- return -EPROBE_DEFER;
-}
-EXPORT_SYMBOL_GPL(drm_of_find_panel_or_bridge);
-
enum drm_of_lvds_pixels {
DRM_OF_LVDS_EVEN = BIT(0),
DRM_OF_LVDS_ODD = BIT(1),
diff --git a/drivers/gpu/drm/fsl-dcu/Kconfig b/drivers/gpu/drm/fsl-dcu/Kconfig
index 0e0f910ceb9f..7f0e851e8508 100644
--- a/drivers/gpu/drm/fsl-dcu/Kconfig
+++ b/drivers/gpu/drm/fsl-dcu/Kconfig
@@ -7,6 +7,7 @@ config DRM_FSL_DCU
select DRM_GEM_DMA_HELPER
select DRM_KMS_HELPER
select DRM_PANEL
+ select DRM_PANEL_BRIDGE
select REGMAP_MMIO
select VIDEOMODE_HELPERS
select MFD_SYSCON if SOC_LS1021A
diff --git a/drivers/gpu/drm/imx/dcss/Kconfig b/drivers/gpu/drm/imx/dcss/Kconfig
index e014ed3ae66c..aa2a20ef5910 100644
--- a/drivers/gpu/drm/imx/dcss/Kconfig
+++ b/drivers/gpu/drm/imx/dcss/Kconfig
@@ -6,6 +6,8 @@ config DRM_IMX_DCSS
select DRM_DISPLAY_HELPER
select DRM_BRIDGE_CONNECTOR
select DRM_GEM_DMA_HELPER
+ select DRM_PANEL
+ select DRM_PANEL_BRIDGE
select VIDEOMODE_HELPERS
depends on DRM && ((ARCH_MXC && ARM64) || COMPILE_TEST)
help
diff --git a/drivers/gpu/drm/ingenic/Kconfig b/drivers/gpu/drm/ingenic/Kconfig
index 04ecfb0c5dd6..987ed42f6f7a 100644
--- a/drivers/gpu/drm/ingenic/Kconfig
+++ b/drivers/gpu/drm/ingenic/Kconfig
@@ -7,6 +7,7 @@ config DRM_INGENIC
depends on COMMON_CLK
select DRM_BRIDGE
select DRM_CLIENT_SELECTION
+ select DRM_PANEL
select DRM_PANEL_BRIDGE
select DRM_KMS_HELPER
select DRM_DISPLAY_HELPER
diff --git a/drivers/gpu/drm/logicvc/Kconfig b/drivers/gpu/drm/logicvc/Kconfig
index 579a358ed5cf..7d2c0a460eec 100644
--- a/drivers/gpu/drm/logicvc/Kconfig
+++ b/drivers/gpu/drm/logicvc/Kconfig
@@ -6,6 +6,8 @@ config DRM_LOGICVC
select DRM_KMS_HELPER
select DRM_KMS_DMA_HELPER
select DRM_GEM_DMA_HELPER
+ select DRM_PANEL
+ select DRM_PANEL_BRIDGE
select REGMAP
select REGMAP_MMIO
help
diff --git a/drivers/gpu/drm/mcde/Kconfig b/drivers/gpu/drm/mcde/Kconfig
index 3516c8d2a5d9..6ebfb930cbfa 100644
--- a/drivers/gpu/drm/mcde/Kconfig
+++ b/drivers/gpu/drm/mcde/Kconfig
@@ -9,6 +9,7 @@ config DRM_MCDE
select DRM_CLIENT_SELECTION
select DRM_MIPI_DSI
select DRM_BRIDGE
+ select DRM_PANEL
select DRM_PANEL_BRIDGE
select DRM_KMS_HELPER
select DRM_GEM_DMA_HELPER
diff --git a/drivers/gpu/drm/pl111/Kconfig b/drivers/gpu/drm/pl111/Kconfig
index 82e918820950..20201ec20aa7 100644
--- a/drivers/gpu/drm/pl111/Kconfig
+++ b/drivers/gpu/drm/pl111/Kconfig
@@ -9,6 +9,7 @@ config DRM_PL111
select DRM_KMS_HELPER
select DRM_GEM_DMA_HELPER
select DRM_BRIDGE
+ select DRM_PANEL
select DRM_PANEL_BRIDGE
help
Choose this option for DRM support for the PL111 CLCD controller.
diff --git a/drivers/gpu/drm/renesas/rcar-du/Kconfig b/drivers/gpu/drm/renesas/rcar-du/Kconfig
index 840305fdeb49..051b0967008c 100644
--- a/drivers/gpu/drm/renesas/rcar-du/Kconfig
+++ b/drivers/gpu/drm/renesas/rcar-du/Kconfig
@@ -47,6 +47,7 @@ config DRM_RCAR_LVDS
depends on PM
select DRM_KMS_HELPER
select DRM_PANEL
+ select DRM_PANEL_BRIDGE
select RESET_CONTROLLER
config DRM_RCAR_USE_MIPI_DSI
diff --git a/drivers/gpu/drm/rockchip/Kconfig b/drivers/gpu/drm/rockchip/Kconfig
index e7f49fe845ea..0b20f472dbd1 100644
--- a/drivers/gpu/drm/rockchip/Kconfig
+++ b/drivers/gpu/drm/rockchip/Kconfig
@@ -124,6 +124,8 @@ config ROCKCHIP_LVDS
depends on PINCTRL && OF
select DRM_DISPLAY_HELPER
select DRM_BRIDGE_CONNECTOR
+ select DRM_PANEL
+ select DRM_PANEL_BRIDGE
help
Choose this option to enable support for Rockchip LVDS controllers.
Rockchip rk3288 SoC has LVDS TX Controller can be used, and it
@@ -136,6 +138,8 @@ config ROCKCHIP_RGB
depends on PINCTRL
select DRM_DISPLAY_HELPER
select DRM_BRIDGE_CONNECTOR
+ select DRM_PANEL
+ select DRM_PANEL_BRIDGE
help
Choose this option to enable support for Rockchip RGB output.
Some Rockchip CRTCs, like rv1108, can directly output parallel
diff --git a/drivers/gpu/drm/stm/Kconfig b/drivers/gpu/drm/stm/Kconfig
index 635be0ac00af..1e3205aa2c7e 100644
--- a/drivers/gpu/drm/stm/Kconfig
+++ b/drivers/gpu/drm/stm/Kconfig
@@ -6,6 +6,7 @@ config DRM_STM
select DRM_CLIENT_SELECTION
select DRM_KMS_HELPER
select DRM_GEM_DMA_HELPER
+ select DRM_PANEL
select DRM_PANEL_BRIDGE
select VIDEOMODE_HELPERS
select FB_PROVIDE_GET_FB_UNMAPPED_AREA if FB
diff --git a/drivers/gpu/drm/sun4i/Kconfig b/drivers/gpu/drm/sun4i/Kconfig
index b56ba00aabca..32c30e08cf5c 100644
--- a/drivers/gpu/drm/sun4i/Kconfig
+++ b/drivers/gpu/drm/sun4i/Kconfig
@@ -7,6 +7,7 @@ config DRM_SUN4I
select DRM_GEM_DMA_HELPER
select DRM_KMS_HELPER
select DRM_PANEL
+ select DRM_PANEL_BRIDGE
select REGMAP_MMIO
select VIDEOMODE_HELPERS
help
diff --git a/drivers/gpu/drm/tegra/Kconfig b/drivers/gpu/drm/tegra/Kconfig
index 8a3b16aac5d6..fdcb10a4c7b5 100644
--- a/drivers/gpu/drm/tegra/Kconfig
+++ b/drivers/gpu/drm/tegra/Kconfig
@@ -14,6 +14,7 @@ config DRM_TEGRA
select DRM_KMS_HELPER
select DRM_MIPI_DSI
select DRM_PANEL
+ select DRM_PANEL_BRIDGE
select FB_DMAMEM_HELPERS if DRM_FBDEV_EMULATION
select TEGRA_HOST1X
select INTERCONNECT
diff --git a/drivers/gpu/drm/tidss/Kconfig b/drivers/gpu/drm/tidss/Kconfig
index 31ad582b7602..863930ecda1e 100644
--- a/drivers/gpu/drm/tidss/Kconfig
+++ b/drivers/gpu/drm/tidss/Kconfig
@@ -7,6 +7,8 @@ config DRM_TIDSS
select DRM_DISPLAY_HELPER
select DRM_BRIDGE_CONNECTOR
select DRM_GEM_DMA_HELPER
+ select DRM_PANEL
+ select DRM_PANEL_BRIDGE
help
The TI Keystone family SoCs introduced a new generation of
Display SubSystem. There is currently three Keystone family
diff --git a/drivers/gpu/drm/tve200/Kconfig b/drivers/gpu/drm/tve200/Kconfig
index a9d6fe535d88..c0746ae8f703 100644
--- a/drivers/gpu/drm/tve200/Kconfig
+++ b/drivers/gpu/drm/tve200/Kconfig
@@ -7,6 +7,7 @@ config DRM_TVE200
depends on OF
select DRM_BRIDGE
select DRM_CLIENT_SELECTION
+ select DRM_PANEL
select DRM_PANEL_BRIDGE
select DRM_KMS_HELPER
select DRM_GEM_DMA_HELPER
diff --git a/include/drm/drm_bridge.h b/include/drm/drm_bridge.h
index 58fff047f43b..c5b82e6946f5 100644
--- a/include/drm/drm_bridge.h
+++ b/include/drm/drm_bridge.h
@@ -1507,6 +1507,10 @@ struct drm_bridge *devm_drm_of_get_bridge(struct device *dev, struct device_node
u32 port, u32 endpoint);
struct drm_bridge *drmm_of_get_bridge(struct drm_device *drm, struct device_node *node,
u32 port, u32 endpoint);
+int drm_of_find_panel_or_bridge(const struct device_node *np,
+ int port, int endpoint,
+ struct drm_panel **panel,
+ struct drm_bridge **bridge);
#else
static inline struct drm_bridge *devm_drm_of_get_bridge(struct device *dev,
struct device_node *node,
@@ -1523,6 +1527,14 @@ static inline struct drm_bridge *drmm_of_get_bridge(struct drm_device *drm,
{
return ERR_PTR(-ENODEV);
}
+
+static inline int drm_of_find_panel_or_bridge(const struct device_node *np,
+ int port, int endpoint,
+ struct drm_panel **panel,
+ struct drm_bridge **bridge)
+{
+ return -EINVAL;
+}
#endif
void devm_drm_put_bridge(struct device *dev, struct drm_bridge *bridge);
diff --git a/include/drm/drm_of.h b/include/drm/drm_of.h
index ebebed14c611..402f5db11e47 100644
--- a/include/drm/drm_of.h
+++ b/include/drm/drm_of.h
@@ -51,10 +51,6 @@ int drm_of_encoder_active_endpoint(struct device_node *node,
struct of_endpoint *endpoint);
int drm_of_get_panel_orientation(const struct device_node *np,
enum drm_panel_orientation *orientation);
-int drm_of_find_panel_or_bridge(const struct device_node *np,
- int port, int endpoint,
- struct drm_panel **panel,
- struct drm_bridge **bridge);
int drm_of_lvds_get_dual_link_pixel_order(const struct device_node *port1,
const struct device_node *port2);
int drm_of_lvds_get_dual_link_pixel_order_sink(struct device_node *port1,
@@ -112,14 +108,6 @@ static inline int drm_of_get_panel_orientation(const struct device_node *np,
return -EINVAL;
}
-static inline int drm_of_find_panel_or_bridge(const struct device_node *np,
- int port, int endpoint,
- struct drm_panel **panel,
- struct drm_bridge **bridge)
-{
- return -EINVAL;
-}
-
static inline int
drm_of_lvds_get_dual_link_pixel_order(const struct device_node *port1,
const struct device_node *port2)
--
2.55.0