drm/rockchip: Add RK3588 DPTX output support

Add driver extension for Synopsys DesignWare DPTX IP used
on Rockchip RK3588 SoC.

Signed-off-by: Andy Yan <andy.yan@rock-chips.com>
Acked-by: Dmitry Baryshkov <lumag@kernel.org>
Tested-by: Nicolas Frattaroli <nicolas.frattaroli@collabora.com>
Reviewed-by: Heiko Stuebner <heiko@sntech.de>
Link: https://lore.kernel.org/r/20250822063959.692098-4-andyshrk@163.com
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>

drivers/gpu/drm/rockchip/Kconfig

@@ -10,6 +10,7 @@ config DRM_ROCKCHIP
 	select VIDEOMODE_HELPERS
 	select DRM_ANALOGIX_DP if ROCKCHIP_ANALOGIX_DP
 	select DRM_DISPLAY_DP_AUX_BUS if ROCKCHIP_ANALOGIX_DP
+	select DRM_DW_DP if ROCKCHIP_DW_DP
 	select DRM_DW_HDMI if ROCKCHIP_DW_HDMI
 	select DRM_DW_HDMI_QP if ROCKCHIP_DW_HDMI_QP
 	select DRM_DW_MIPI_DSI if ROCKCHIP_DW_MIPI_DSI
@@ -60,6 +61,14 @@ config ROCKCHIP_CDN_DP
 	  RK3399 based SoC, you should select this
 	  option.
 
+config ROCKCHIP_DW_DP
+	bool "Rockchip specific extensions for Synopsys DW DP"
+	help
+	  This selects support for Rockchip SoC specific extensions
+	  to enable Synopsys DesignWare Cores based DisplayPort transmit
+	  controller support on Rockchip SoC, If you want to enable DP on
+	  rk3588 based SoC, you should select this option.
+
 config ROCKCHIP_DW_HDMI
 	bool "Rockchip specific extensions for Synopsys DW HDMI"
 	help

drivers/gpu/drm/rockchip/Makefile

@@ -14,6 +14,7 @@ rockchipdrm-$(CONFIG_ROCKCHIP_DW_HDMI) += dw_hdmi-rockchip.o
 rockchipdrm-$(CONFIG_ROCKCHIP_DW_HDMI_QP) += dw_hdmi_qp-rockchip.o
 rockchipdrm-$(CONFIG_ROCKCHIP_DW_MIPI_DSI) += dw-mipi-dsi-rockchip.o
 rockchipdrm-$(CONFIG_ROCKCHIP_DW_MIPI_DSI2) += dw-mipi-dsi2-rockchip.o
+rockchipdrm-$(CONFIG_ROCKCHIP_DW_DP) += dw_dp-rockchip.o
 rockchipdrm-$(CONFIG_ROCKCHIP_INNO_HDMI) += inno_hdmi.o
 rockchipdrm-$(CONFIG_ROCKCHIP_LVDS) += rockchip_lvds.o
 rockchipdrm-$(CONFIG_ROCKCHIP_RGB) += rockchip_rgb.o

drivers/gpu/drm/rockchip/dw_dp-rockchip.c

@@ -0,0 +1,150 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2020 Rockchip Electronics Co., Ltd.
+ *
+ * Author: Zhang Yubing <yubing.zhang@rock-chips.com>
+ * Author: Andy Yan <andy.yan@rock-chips.com>
+ */
+
+#include <linux/component.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <drm/bridge/dw_dp.h>
+#include <drm/drm_atomic_helper.h>
+#include <drm/drm_bridge.h>
+#include <drm/drm_bridge_connector.h>
+#include <drm/drm_of.h>
+#include <drm/drm_print.h>
+#include <drm/drm_probe_helper.h>
+#include <drm/drm_simple_kms_helper.h>
+
+#include <linux/media-bus-format.h>
+#include <linux/videodev2.h>
+
+#include "rockchip_drm_drv.h"
+#include "rockchip_drm_vop.h"
+
+struct rockchip_dw_dp {
+	struct dw_dp *base;
+	struct device *dev;
+	struct rockchip_encoder encoder;
+};
+
+static int dw_dp_encoder_atomic_check(struct drm_encoder *encoder,
+				      struct drm_crtc_state *crtc_state,
+				      struct drm_connector_state *conn_state)
+{
+	struct rockchip_crtc_state *s = to_rockchip_crtc_state(crtc_state);
+	struct drm_atomic_state *state = conn_state->state;
+	struct drm_display_info *di = &conn_state->connector->display_info;
+	struct drm_bridge *bridge  = drm_bridge_chain_get_first_bridge(encoder);
+	struct drm_bridge_state *bridge_state = drm_atomic_get_new_bridge_state(state, bridge);
+	u32 bus_format = bridge_state->input_bus_cfg.format;
+
+	switch (bus_format) {
+	case MEDIA_BUS_FMT_UYYVYY10_0_5X30:
+	case MEDIA_BUS_FMT_UYYVYY8_0_5X24:
+		s->output_mode = ROCKCHIP_OUT_MODE_YUV420;
+		break;
+	case MEDIA_BUS_FMT_YUYV10_1X20:
+	case MEDIA_BUS_FMT_YUYV8_1X16:
+		s->output_mode = ROCKCHIP_OUT_MODE_S888_DUMMY;
+		break;
+	case MEDIA_BUS_FMT_RGB101010_1X30:
+	case MEDIA_BUS_FMT_RGB888_1X24:
+	case MEDIA_BUS_FMT_RGB666_1X24_CPADHI:
+	case MEDIA_BUS_FMT_YUV10_1X30:
+	case MEDIA_BUS_FMT_YUV8_1X24:
+	default:
+		s->output_mode = ROCKCHIP_OUT_MODE_AAAA;
+		break;
+	}
+
+	s->output_type = DRM_MODE_CONNECTOR_DisplayPort;
+	s->bus_format = bus_format;
+	s->bus_flags = di->bus_flags;
+	s->color_space = V4L2_COLORSPACE_DEFAULT;
+
+	return 0;
+}
+
+static const struct drm_encoder_helper_funcs dw_dp_encoder_helper_funcs = {
+	.atomic_check		= dw_dp_encoder_atomic_check,
+};
+
+static int dw_dp_rockchip_bind(struct device *dev, struct device *master, void *data)
+{
+	struct platform_device *pdev = to_platform_device(dev);
+	struct dw_dp_plat_data plat_data;
+	struct drm_device *drm_dev = data;
+	struct rockchip_dw_dp *dp;
+	struct drm_encoder *encoder;
+	struct drm_connector *connector;
+	int ret;
+
+	dp = devm_kzalloc(dev, sizeof(*dp), GFP_KERNEL);
+	if (!dp)
+		return -ENOMEM;
+
+	dp->dev = dev;
+	platform_set_drvdata(pdev, dp);
+
+	plat_data.max_link_rate = 810000;
+	encoder = &dp->encoder.encoder;
+	encoder->possible_crtcs = drm_of_find_possible_crtcs(drm_dev, dev->of_node);
+	rockchip_drm_encoder_set_crtc_endpoint_id(&dp->encoder, dev->of_node, 0, 0);
+
+	ret = drmm_encoder_init(drm_dev, encoder, NULL, DRM_MODE_ENCODER_TMDS, NULL);
+	if (ret)
+		return ret;
+	drm_encoder_helper_add(encoder, &dw_dp_encoder_helper_funcs);
+
+	dp->base = dw_dp_bind(dev, encoder, &plat_data);
+	if (IS_ERR(dp->base)) {
+		ret = PTR_ERR(dp->base);
+		return ret;
+	}
+
+	connector = drm_bridge_connector_init(drm_dev, encoder);
+	if (IS_ERR(connector)) {
+		ret = PTR_ERR(connector);
+		return dev_err_probe(dev, ret, "Failed to init bridge connector");
+	}
+
+	drm_connector_attach_encoder(connector, encoder);
+
+	return 0;
+}
+
+static const struct component_ops dw_dp_rockchip_component_ops = {
+	.bind = dw_dp_rockchip_bind,
+};
+
+static int dw_dp_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+
+	return component_add(dev, &dw_dp_rockchip_component_ops);
+}
+
+static void dw_dp_remove(struct platform_device *pdev)
+{
+	struct rockchip_dw_dp *dp = platform_get_drvdata(pdev);
+
+	component_del(dp->dev, &dw_dp_rockchip_component_ops);
+}
+
+static const struct of_device_id dw_dp_of_match[] = {
+	{ .compatible = "rockchip,rk3588-dp", },
+	{}
+};
+MODULE_DEVICE_TABLE(of, dw_dp_of_match);
+
+struct platform_driver dw_dp_driver = {
+	.probe	= dw_dp_probe,
+	.remove = dw_dp_remove,
+	.driver = {
+		.name = "dw-dp",
+		.of_match_table = dw_dp_of_match,
+	},
+};

drivers/gpu/drm/rockchip/rockchip_drm_drv.c

@@ -529,6 +529,7 @@ static int __init rockchip_drm_init(void)
 	ADD_ROCKCHIP_SUB_DRIVER(rockchip_dp_driver,
 				CONFIG_ROCKCHIP_ANALOGIX_DP);
 	ADD_ROCKCHIP_SUB_DRIVER(cdn_dp_driver, CONFIG_ROCKCHIP_CDN_DP);
+	ADD_ROCKCHIP_SUB_DRIVER(dw_dp_driver, CONFIG_ROCKCHIP_DW_DP);
 	ADD_ROCKCHIP_SUB_DRIVER(dw_hdmi_rockchip_pltfm_driver,
 				CONFIG_ROCKCHIP_DW_HDMI);
 	ADD_ROCKCHIP_SUB_DRIVER(dw_hdmi_qp_rockchip_pltfm_driver,

drivers/gpu/drm/rockchip/rockchip_drm_drv.h

@@ -87,6 +87,7 @@ int rockchip_drm_encoder_set_crtc_endpoint_id(struct rockchip_encoder *rencoder,
 					      struct device_node *np, int port, int reg);
 int rockchip_drm_endpoint_is_subdriver(struct device_node *ep);
 extern struct platform_driver cdn_dp_driver;
+extern struct platform_driver dw_dp_driver;
 extern struct platform_driver dw_hdmi_rockchip_pltfm_driver;
 extern struct platform_driver dw_hdmi_qp_rockchip_pltfm_driver;
 extern struct platform_driver dw_mipi_dsi_rockchip_driver;