[PATCH 0/3] usb: dwc3: support two connectors sharing one HS data bus

[Qianhui Xu]

From: Xu Qianhui <xiaqinghuan@xxxxxxxxxxxxxxxx>

Some boards wire the High Speed data lines of a single DWC3 controller to
two receptacles and select between them with a GPIO, while the SuperSpeed
lanes stay per connector.  This series makes such a design usable:

  - patch 1 documents "usb-psy-name", a property the dwc3 glue drivers
    already parse but which the bindings never described;

  - patch 2 describes the two-connector HS data path: "port-select-gpios"
    plus a "ports" node whose connector endpoints carry "mux-state" (the
    logical port-select level of that connector) and "usb-role-switch";

  - patch 3 adds the driver side: one role switch per connector, mutual
    arbitration between them, and a data-path switch performed after the
    previous host/gadget instance has been torn down.

Single-connector designs are unaffected: the mux path is only taken when
"port-select-gpios" is present.

This work was developed on the Qualcomm SM8750 (Lenovo TB322FC) tablet;
the board device tree is not upstream yet, so no in-tree user is switched
over by this series.

Xu Qianhui (3):
  dt-bindings: usb: snps,dwc3: document usb-psy-name
  dt-bindings: usb: snps,dwc3: describe the two-connector HS data path
  usb: dwc3: support two connectors sharing one HS data bus

 .../bindings/usb/snps,dwc3-common.yaml        |  65 ++++++-
 drivers/usb/dwc3/core.c                       |  30 ++-
 drivers/usb/dwc3/core.h                       |  22 +++
 drivers/usb/dwc3/debugfs.c                    |   4 +
 drivers/usb/dwc3/drd.c                        | 177 +++++++++++++++++-
 5 files changed, 294 insertions(+), 4 deletions(-)