phy: rockchip: add usbdp combo phy driver

This adds a new USBDP combo PHY with Samsung IP block driver.

The driver get lane mux and mapping info in 2 ways, supporting
DisplayPort alternate mode or parsing from DT. When parsing from DT,
the property "rockchip,dp-lane-mux" provide the DP mux and mapping info.

When do DP link training, need to set lane number, link rate, swing, and
pre-emphasis via PHY configure interface.

Co-developed-by: Zhang Yubing <yubing.zhang@rock-chips.com>
Signed-off-by: Zhang Yubing <yubing.zhang@rock-chips.com>
Co-developed-by: Frank Wang <frank.wang@rock-chips.com>
Signed-off-by: Frank Wang <frank.wang@rock-chips.com>
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>

drivers/phy/rockchip/Kconfig

@@ -107,3 +107,15 @@ config PHY_ROCKCHIP_USB
 	select GENERIC_PHY
 	help
 	  Enable this to support the Rockchip USB 2.0 PHY.
+
+config PHY_ROCKCHIP_USBDP
+	tristate "Rockchip USBDP COMBO PHY Driver"
+	depends on ARCH_ROCKCHIP && OF
+	select GENERIC_PHY
+	select TYPEC
+	help
+	  Enable this to support the Rockchip USB3.0/DP combo PHY with
+	  Samsung IP block. This is required for USB3 support on RK3588.
+
+	  To compile this driver as a module, choose M here: the module
+	  will be called phy-rockchip-usbdp

drivers/phy/rockchip/Makefile

@@ -11,3 +11,4 @@ obj-$(CONFIG_PHY_ROCKCHIP_PCIE)		+= phy-rockchip-pcie.o
 obj-$(CONFIG_PHY_ROCKCHIP_SNPS_PCIE3)	+= phy-rockchip-snps-pcie3.o
 obj-$(CONFIG_PHY_ROCKCHIP_TYPEC)	+= phy-rockchip-typec.o
 obj-$(CONFIG_PHY_ROCKCHIP_USB)		+= phy-rockchip-usb.o
+obj-$(CONFIG_PHY_ROCKCHIP_USBDP)	+= phy-rockchip-usbdp.o