drm/bridge: Add encoder parameter to drm_bridge_funcs.attach

The drm_bridge structure contains an encoder pointer that is widely used
by bridge drivers. This pattern is largely documented as deprecated in
other KMS entities for atomic drivers.

However, one of the main use of that pointer is done in attach to just
call drm_bridge_attach on the next bridge to add it to the bridge list.
While this dereferences the bridge->encoder pointer, it's effectively
the same encoder the bridge was being attached to.

We can make it more explicit by adding the encoder the bridge is
attached to to the list of attach parameters. This also removes the need
to dereference bridge->encoder in most drivers.

Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Tested-by: Douglas Anderson <dianders@chromium.org>
Tested-by: Luca Ceresoli <luca.ceresoli@bootlin.com>
Reviewed-by: Luca Ceresoli <luca.ceresoli@bootlin.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20250313-bridge-connector-v6-1-511c54a604fb@kernel.org
Signed-off-by: Maxime Ripard <mripard@kernel.org>

6 files changed, 12 insertions, 6 deletions

diff --git a/drivers/gpu/drm/omapdrm/dss/dpi.c b/drivers/gpu/drm/omapdrm/dss/dpi.c
index b17e77f700dd..6eff97a09160 100644
--- a/drivers/gpu/drm/omapdrm/dss/dpi.c
+++ b/drivers/gpu/drm/omapdrm/dss/dpi.c
@@ -420,6 +420,7 @@ static void dpi_init_pll(struct dpi_data *dpi)
  */
 
 static int dpi_bridge_attach(struct drm_bridge *bridge,
+			     struct drm_encoder *encoder,
 			     enum drm_bridge_attach_flags flags)
 {
 	struct dpi_data *dpi = drm_bridge_to_dpi(bridge);
@@ -429,7 +430,7 @@ static int dpi_bridge_attach(struct drm_bridge *bridge,
 
 	dpi_init_pll(dpi);
 
-	return drm_bridge_attach(bridge->encoder, dpi->output.next_bridge,
+	return drm_bridge_attach(encoder, dpi->output.next_bridge,
 				 bridge, flags);
 }
 
diff --git a/drivers/gpu/drm/omapdrm/dss/dsi.c b/drivers/gpu/drm/omapdrm/dss/dsi.c
index 59d20eb8a7e0..35e3e332bdcf 100644
--- a/drivers/gpu/drm/omapdrm/dss/dsi.c
+++ b/drivers/gpu/drm/omapdrm/dss/dsi.c
@@ -4617,6 +4617,7 @@ static const struct component_ops dsi_component_ops = {
  */
 
 static int dsi_bridge_attach(struct drm_bridge *bridge,
+			     struct drm_encoder *encoder,
 			     enum drm_bridge_attach_flags flags)
 {
 	struct dsi_data *dsi = drm_bridge_to_dsi(bridge);
@@ -4624,7 +4625,7 @@ static int dsi_bridge_attach(struct drm_bridge *bridge,
 	if (!(flags & DRM_BRIDGE_ATTACH_NO_CONNECTOR))
 		return -EINVAL;
 
-	return drm_bridge_attach(bridge->encoder, dsi->output.next_bridge,
+	return drm_bridge_attach(encoder, dsi->output.next_bridge,
 				 bridge, flags);
 }
 
diff --git a/drivers/gpu/drm/omapdrm/dss/hdmi4.c b/drivers/gpu/drm/omapdrm/dss/hdmi4.c
index e1ac447221ee..a3b22952fdc3 100644
--- a/drivers/gpu/drm/omapdrm/dss/hdmi4.c
+++ b/drivers/gpu/drm/omapdrm/dss/hdmi4.c
@@ -314,6 +314,7 @@ void hdmi4_core_disable(struct hdmi_core_data *core)
  */
 
 static int hdmi4_bridge_attach(struct drm_bridge *bridge,
+			       struct drm_encoder *encoder,
 			       enum drm_bridge_attach_flags flags)
 {
 	struct omap_hdmi *hdmi = drm_bridge_to_hdmi(bridge);
@@ -321,7 +322,7 @@ static int hdmi4_bridge_attach(struct drm_bridge *bridge,
 	if (!(flags & DRM_BRIDGE_ATTACH_NO_CONNECTOR))
 		return -EINVAL;
 
-	return drm_bridge_attach(bridge->encoder, hdmi->output.next_bridge,
+	return drm_bridge_attach(encoder, hdmi->output.next_bridge,
 				 bridge, flags);
 }
 
diff --git a/drivers/gpu/drm/omapdrm/dss/hdmi5.c b/drivers/gpu/drm/omapdrm/dss/hdmi5.c
index fa9904e4c218..0c98444d39a9 100644
--- a/drivers/gpu/drm/omapdrm/dss/hdmi5.c
+++ b/drivers/gpu/drm/omapdrm/dss/hdmi5.c
@@ -312,6 +312,7 @@ static void hdmi_core_disable(struct omap_hdmi *hdmi)
  */
 
 static int hdmi5_bridge_attach(struct drm_bridge *bridge,
+			       struct drm_encoder *encoder,
 			       enum drm_bridge_attach_flags flags)
 {
 	struct omap_hdmi *hdmi = drm_bridge_to_hdmi(bridge);
@@ -319,7 +320,7 @@ static int hdmi5_bridge_attach(struct drm_bridge *bridge,
 	if (!(flags & DRM_BRIDGE_ATTACH_NO_CONNECTOR))
 		return -EINVAL;
 
-	return drm_bridge_attach(bridge->encoder, hdmi->output.next_bridge,
+	return drm_bridge_attach(encoder, hdmi->output.next_bridge,
 				 bridge, flags);
 }
 
diff --git a/drivers/gpu/drm/omapdrm/dss/sdi.c b/drivers/gpu/drm/omapdrm/dss/sdi.c
index f9ae358e8e52..e78826e4b560 100644
--- a/drivers/gpu/drm/omapdrm/dss/sdi.c
+++ b/drivers/gpu/drm/omapdrm/dss/sdi.c
@@ -128,6 +128,7 @@ static void sdi_config_lcd_manager(struct sdi_device *sdi)
  */
 
 static int sdi_bridge_attach(struct drm_bridge *bridge,
+			     struct drm_encoder *encoder,
 			     enum drm_bridge_attach_flags flags)
 {
 	struct sdi_device *sdi = drm_bridge_to_sdi(bridge);
@@ -135,7 +136,7 @@ static int sdi_bridge_attach(struct drm_bridge *bridge,
 	if (!(flags & DRM_BRIDGE_ATTACH_NO_CONNECTOR))
 		return -EINVAL;
 
-	return drm_bridge_attach(bridge->encoder, sdi->output.next_bridge,
+	return drm_bridge_attach(encoder, sdi->output.next_bridge,
 				 bridge, flags);
 }
 
diff --git a/drivers/gpu/drm/omapdrm/dss/venc.c b/drivers/gpu/drm/omapdrm/dss/venc.c
index aaeef603682c..50349518eda1 100644
--- a/drivers/gpu/drm/omapdrm/dss/venc.c
+++ b/drivers/gpu/drm/omapdrm/dss/venc.c
@@ -538,6 +538,7 @@ static int venc_get_clocks(struct venc_device *venc)
  */
 
 static int venc_bridge_attach(struct drm_bridge *bridge,
+			      struct drm_encoder *encoder,
 			      enum drm_bridge_attach_flags flags)
 {
 	struct venc_device *venc = drm_bridge_to_venc(bridge);
@@ -545,7 +546,7 @@ static int venc_bridge_attach(struct drm_bridge *bridge,
 	if (!(flags & DRM_BRIDGE_ATTACH_NO_CONNECTOR))
 		return -EINVAL;
 
-	return drm_bridge_attach(bridge->encoder, venc->output.next_bridge,
+	return drm_bridge_attach(encoder, venc->output.next_bridge,
 				 bridge, flags);
 }