[PATCH 0/2] arm64: dts: rockchip: add USB-C PD and DP altmode to LubanCat 4

[Pufan Jin <cyan2254650260@gmail.com>]

This series enables the front-panel USB Type-C port on the EmbedFire
LubanCat 4 single-board computer, covering USB Power Delivery, dual-role
data/power, and DisplayPort alternate mode.

The port is backed by a Fairchild FUSB302 controller on I2C1 (0x22),
a fixed 5V VBUS regulator enabled by GPIO1_C1 (limited to 2A by an
LPW5209 switch), the RK3588 combo PHY usbdp_phy0, and two DC switches
on GPIO4_B3/B4 for the SBU1/SBU2 lines.

The series is organized into two steps:

1. Basic Type-C and USB PD support:
   Adds the FUSB302 node, VBUS regulator, dual-role power (source 5V/2A,
   sink 5V/1A) and dual-role data connector.  Sets usb_host0_xhci to
   OTG mode with usb-role-switch, wires HS data to the host controller
   and SS data to usbdp_phy0, and adds orientation-switch on the PHY.

2. DisplayPort alternate mode:
   Adds the DisplayPort altmode entry (SVID 0xff01) to the connector,
   wires connector SBU (port@2) to usbdp_phy0 (port@3), and connects
   the display pipeline: VOP2 VP1 -> dp0 -> usbdp_phy0 (port@2).

Validation and hardware test status:
- 'make dtbs' builds cleanly without warnings.
- 'make dtbs_check' against usb-connector, phy-rockchip-usbdp,
  rockchip,dw-dp, and fcs,fusb302 schemas passes with 0 warnings.
- Patch 1 has been verified on a physical LubanCat 4 board:
  * tcpm and fusb302 probe cleanly;
  * Host mode: USB 2.0 and USB 3.0 peripherals enumerate; USB 3.0
    operates at SuperSpeed in normal orientation (reverse-orientation
    SuperSpeed is subject to the known upstream phy-rockchip-usbdp bug);
  * Device mode: ConfigFS CDC ACM serial gadget successfully enumerates
    on a host PC at high-speed with bidirectional data communication;
  * VBUS power switch correctly enables in source mode and remains
    disabled in sink mode with reverse current blocked.
- Patch 2 driver stack registration has been verified on board:
  dw_dp binds to the display subsystem, DRM connector card2-DP-1 is
  registered, usbdp phy-mux and phy-switch are registered, and
  typec_displayport binds to the altmode.  Display output / link
  training is disclosed as pending physical verification due to lack
  of a USB-C to DP monitor/cable at this time.

Pufan Jin (2):
  arm64: dts: rockchip: add USB-C PD support to LubanCat 4
  arm64: dts: rockchip: add USB-C DP altmode support to LubanCat 4

 .../boot/dts/rockchip/rk3588s-lubancat-4.dts  | 172 +++++++++++++++++-
 1 file changed, 171 insertions(+), 1 deletion(-)

-- 
2.56.0