drm/bridge: Move legacy bridge driver out of imx directory for multi-platform use

As suggested by Dmitry, the DRM legacy bridge driver can be pulled
out of imx/ subdir for multi-platform use. The driver is also renamed
to make it more generic and suitable for platforms other than i.MX.

Signed-off-by: Damon Ding <damon.ding@rock-chips.com>
Suggested-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>
Reviewed-by: Luca Ceresoli <luca.ceresoli@bootlin.com>
Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Tested-by: Heiko Stuebner <heiko@sntech.de> # rk3588
Link: https://patch.msgid.link/20260409065301.446670-3-damon.ding@rock-chips.com
Signed-off-by: Luca Ceresoli <luca.ceresoli@bootlin.com>

drivers/gpu/drm/bridge/Kconfig

@@ -262,6 +262,16 @@ config DRM_NXP_PTN3460
 	help
 	  NXP PTN3460 eDP-LVDS bridge chip driver.
 
+config DRM_OF_DISPLAY_MODE_BRIDGE
+	tristate
+	depends on DRM_BRIDGE && OF
+	help
+	  This is a DRM bridge implementation that uses of_get_drm_display_mode
+	  to acquire display mode.
+
+	  It exists for compatibility with legacy display mode parsing, in order
+	  to conform to the panel-bridge framework.
+
 config DRM_PARADE_PS8622
 	tristate "Parade eDP/LVDS bridge"
 	depends on OF

drivers/gpu/drm/bridge/Makefile

@@ -22,6 +22,7 @@ obj-$(CONFIG_DRM_LVDS_CODEC) += lvds-codec.o
 obj-$(CONFIG_DRM_MEGACHIPS_STDPXXXX_GE_B850V3_FW) += megachips-stdpxxxx-ge-b850v3-fw.o
 obj-$(CONFIG_DRM_MICROCHIP_LVDS_SERIALIZER) += microchip-lvds.o
 obj-$(CONFIG_DRM_NXP_PTN3460) += nxp-ptn3460.o
+obj-$(CONFIG_DRM_OF_DISPLAY_MODE_BRIDGE) += of-display-mode-bridge.o
 obj-$(CONFIG_DRM_PARADE_PS8622) += parade-ps8622.o
 obj-$(CONFIG_DRM_PARADE_PS8640) += parade-ps8640.o
 obj-$(CONFIG_DRM_SAMSUNG_DSIM) += samsung-dsim.o

drivers/gpu/drm/bridge/imx/Kconfig

@@ -3,16 +3,6 @@ if ARCH_MXC || COMPILE_TEST
 config DRM_IMX_LDB_HELPER
 	tristate
 
-config DRM_IMX_LEGACY_BRIDGE
-	tristate
-	depends on DRM_IMX
-	help
-	  This is a DRM bridge implementation for the DRM i.MX IPUv3 driver,
-	  that uses of_get_drm_display_mode to acquire display mode.
-
-	  Newer designs should not use this bridge and should use proper panel
-	  driver instead.
-
 config DRM_IMX8MP_DW_HDMI_BRIDGE
 	tristate "Freescale i.MX8MP HDMI-TX bridge support"
 	depends on OF

drivers/gpu/drm/bridge/imx/Makefile

@@ -1,5 +1,4 @@
 obj-$(CONFIG_DRM_IMX_LDB_HELPER) += imx-ldb-helper.o
-obj-$(CONFIG_DRM_IMX_LEGACY_BRIDGE) += imx-legacy-bridge.o
 obj-$(CONFIG_DRM_IMX8MP_DW_HDMI_BRIDGE) += imx8mp-hdmi-tx.o
 obj-$(CONFIG_DRM_IMX8MP_HDMI_PAI) += imx8mp-hdmi-pai.o
 obj-$(CONFIG_DRM_IMX8MP_HDMI_PVI) += imx8mp-hdmi-pvi.o

drivers/gpu/drm/bridge/imx/imx-legacy-bridge.c

@@ -1,91 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0+
-/*
- * Freescale i.MX drm driver
- *
- * bridge driver for legacy DT bindings, utilizing display-timings node
- */
-
-#include <linux/export.h>
-
-#include <drm/drm_bridge.h>
-#include <drm/drm_modes.h>
-#include <drm/drm_probe_helper.h>
-#include <drm/bridge/imx.h>
-
-#include <video/of_display_timing.h>
-#include <video/of_videomode.h>
-
-struct imx_legacy_bridge {
-	struct drm_bridge base;
-
-	struct drm_display_mode mode;
-	u32 bus_flags;
-};
-
-#define to_imx_legacy_bridge(bridge)	container_of(bridge, struct imx_legacy_bridge, base)
-
-static int imx_legacy_bridge_attach(struct drm_bridge *bridge,
-				    struct drm_encoder *encoder,
-				    enum drm_bridge_attach_flags flags)
-{
-	if (!(flags & DRM_BRIDGE_ATTACH_NO_CONNECTOR))
-		return -EINVAL;
-
-	return 0;
-}
-
-static int imx_legacy_bridge_get_modes(struct drm_bridge *bridge,
-				       struct drm_connector *connector)
-{
-	struct imx_legacy_bridge *imx_bridge = to_imx_legacy_bridge(bridge);
-	int ret;
-
-	ret = drm_connector_helper_get_modes_fixed(connector, &imx_bridge->mode);
-	if (ret)
-		return ret;
-
-	connector->display_info.bus_flags = imx_bridge->bus_flags;
-
-	return 0;
-}
-
-struct drm_bridge_funcs imx_legacy_bridge_funcs = {
-	.attach = imx_legacy_bridge_attach,
-	.get_modes = imx_legacy_bridge_get_modes,
-};
-
-struct drm_bridge *devm_imx_drm_legacy_bridge(struct device *dev,
-					      struct device_node *np,
-					      int type)
-{
-	struct imx_legacy_bridge *imx_bridge;
-	int ret;
-
-	imx_bridge = devm_drm_bridge_alloc(dev, struct imx_legacy_bridge,
-					   base, &imx_legacy_bridge_funcs);
-	if (IS_ERR(imx_bridge))
-		return ERR_CAST(imx_bridge);
-
-	ret = of_get_drm_display_mode(np,
-				      &imx_bridge->mode,
-				      &imx_bridge->bus_flags,
-				      OF_USE_NATIVE_MODE);
-	if (ret)
-		return ERR_PTR(ret);
-
-	imx_bridge->mode.type |= DRM_MODE_TYPE_DRIVER;
-
-	imx_bridge->base.of_node = np;
-	imx_bridge->base.ops = DRM_BRIDGE_OP_MODES;
-	imx_bridge->base.type = type;
-
-	ret = devm_drm_bridge_add(dev, &imx_bridge->base);
-	if (ret)
-		return ERR_PTR(ret);
-
-	return &imx_bridge->base;
-}
-EXPORT_SYMBOL_GPL(devm_imx_drm_legacy_bridge);
-
-MODULE_LICENSE("GPL");
-MODULE_DESCRIPTION("Freescale i.MX DRM bridge driver for legacy DT bindings");

drivers/gpu/drm/bridge/of-display-mode-bridge.c

@@ -0,0 +1,93 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (C) 2012 Sascha Hauer, Pengutronix
+ *
+ * bridge driver for legacy DT bindings, utilizing display-timings node
+ *
+ * Author: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>
+ */
+
+#include <linux/export.h>
+
+#include <drm/drm_bridge.h>
+#include <drm/drm_modes.h>
+#include <drm/drm_probe_helper.h>
+#include <drm/bridge/of-display-mode-bridge.h>
+
+#include <video/of_display_timing.h>
+#include <video/of_videomode.h>
+
+struct of_display_mode_bridge {
+	struct drm_bridge base;
+
+	struct drm_display_mode mode;
+	u32 bus_flags;
+};
+
+#define to_of_display_mode_bridge(bridge) container_of(bridge, struct of_display_mode_bridge, base)
+
+static int of_display_mode_bridge_attach(struct drm_bridge *bridge,
+					 struct drm_encoder *encoder,
+					 enum drm_bridge_attach_flags flags)
+{
+	if (!(flags & DRM_BRIDGE_ATTACH_NO_CONNECTOR))
+		return -EINVAL;
+
+	return 0;
+}
+
+static int of_display_mode_bridge_get_modes(struct drm_bridge *bridge,
+					    struct drm_connector *connector)
+{
+	struct of_display_mode_bridge *of_bridge = to_of_display_mode_bridge(bridge);
+	int ret;
+
+	ret = drm_connector_helper_get_modes_fixed(connector, &of_bridge->mode);
+	if (ret)
+		return ret;
+
+	connector->display_info.bus_flags = of_bridge->bus_flags;
+
+	return 0;
+}
+
+struct drm_bridge_funcs of_display_mode_bridge_funcs = {
+	.attach = of_display_mode_bridge_attach,
+	.get_modes = of_display_mode_bridge_get_modes,
+};
+
+struct drm_bridge *devm_drm_of_display_mode_bridge(struct device *dev,
+						   struct device_node *np,
+						   int type)
+{
+	struct of_display_mode_bridge *of_bridge;
+	int ret;
+
+	of_bridge = devm_drm_bridge_alloc(dev, struct of_display_mode_bridge,
+					  base, &of_display_mode_bridge_funcs);
+	if (IS_ERR(of_bridge))
+		return ERR_CAST(of_bridge);
+
+	ret = of_get_drm_display_mode(np,
+				      &of_bridge->mode,
+				      &of_bridge->bus_flags,
+				      OF_USE_NATIVE_MODE);
+	if (ret)
+		return ERR_PTR(ret);
+
+	of_bridge->mode.type |= DRM_MODE_TYPE_DRIVER;
+
+	of_bridge->base.of_node = np;
+	of_bridge->base.ops = DRM_BRIDGE_OP_MODES;
+	of_bridge->base.type = type;
+
+	ret = devm_drm_bridge_add(dev, &of_bridge->base);
+	if (ret)
+		return ERR_PTR(ret);
+
+	return &of_bridge->base;
+}
+EXPORT_SYMBOL_GPL(devm_drm_of_display_mode_bridge);
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("DRM bridge driver for legacy DT bindings");

drivers/gpu/drm/imx/ipuv3/Kconfig

@@ -16,7 +16,7 @@ config DRM_IMX_PARALLEL_DISPLAY
 	select DRM_BRIDGE
 	select DRM_BRIDGE_CONNECTOR
 	select DRM_DISPLAY_HELPER
-	select DRM_IMX_LEGACY_BRIDGE
+	select DRM_OF_DISPLAY_MODE_BRIDGE
 	select DRM_PANEL_BRIDGE
 	select VIDEOMODE_HELPERS
 
@@ -37,7 +37,7 @@ config DRM_IMX_LDB
 	select DRM_BRIDGE
 	select DRM_BRIDGE_CONNECTOR
 	select DRM_PANEL_BRIDGE
-	select DRM_IMX_LEGACY_BRIDGE
+	select DRM_OF_DISPLAY_MODE_BRIDGE
 	help
 	  Choose this to enable the internal LVDS Display Bridge (LDB)
 	  found on i.MX53 and i.MX6 processors.

drivers/gpu/drm/imx/ipuv3/imx-ldb.c

@@ -28,7 +28,7 @@
 #include <drm/drm_print.h>
 #include <drm/drm_probe_helper.h>
 #include <drm/drm_simple_kms_helper.h>
-#include <drm/bridge/imx.h>
+#include <drm/bridge/of-display-mode-bridge.h>
 
 #include "imx-drm.h"
 
@@ -605,8 +605,8 @@ static int imx_ldb_probe(struct platform_device *pdev)
 		 * checking the bus_format property.
 		 */
 		if (!channel->bridge) {
-			channel->bridge = devm_imx_drm_legacy_bridge(dev, child,
+			channel->bridge = devm_drm_of_display_mode_bridge(dev, child,
-								     DRM_MODE_CONNECTOR_LVDS);
+									  DRM_MODE_CONNECTOR_LVDS);
 			if (IS_ERR(channel->bridge)) {
 				ret = PTR_ERR(channel->bridge);
 				goto free_child;

drivers/gpu/drm/imx/ipuv3/parallel-display.c

@@ -19,7 +19,7 @@
 #include <drm/drm_of.h>
 #include <drm/drm_probe_helper.h>
 #include <drm/drm_simple_kms_helper.h>
-#include <drm/bridge/imx.h>
+#include <drm/bridge/of-display-mode-bridge.h>
 
 #include "imx-drm.h"
 
@@ -242,7 +242,8 @@ static int imx_pd_probe(struct platform_device *pdev)
 	/* port@1 is the output port */
 	imxpd->next_bridge = devm_drm_of_get_bridge(dev, np, 1, 0);
 	if (imxpd->next_bridge == ERR_PTR(-ENODEV))
-		imxpd->next_bridge = devm_imx_drm_legacy_bridge(dev, np, DRM_MODE_CONNECTOR_DPI);
+		imxpd->next_bridge = devm_drm_of_display_mode_bridge(dev, np,
+								     DRM_MODE_CONNECTOR_DPI);
 	if (IS_ERR(imxpd->next_bridge)) {
 		ret = PTR_ERR(imxpd->next_bridge);
 		return ret;

include/drm/bridge/imx.h

@@ -1,17 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0+
-/*
- * Copyright (C) 2012 Sascha Hauer, Pengutronix
- */
-
-#ifndef DRM_IMX_BRIDGE_H
-#define DRM_IMX_BRIDGE_H
-
-struct device;
-struct device_node;
-struct drm_bridge;
-
-struct drm_bridge *devm_imx_drm_legacy_bridge(struct device *dev,
-					      struct device_node *np,
-					      int type);
-
-#endif

include/drm/bridge/of-display-mode-bridge.h

@@ -0,0 +1,17 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+/*
+ * Copyright (C) 2012 Sascha Hauer, Pengutronix
+ */
+
+#ifndef DRM_OF_DISPLAY_MODE_BRIDGE_H
+#define DRM_OF_DISPLAY_MODE_BRIDGE_H
+
+struct device;
+struct device_node;
+struct drm_bridge;
+
+struct drm_bridge *devm_drm_of_display_mode_bridge(struct device *dev,
+						   struct device_node *np,
+						   int type);
+
+#endif