[PATCH v6 0/8] Add multiport support for DWC3 controllers

[Krishna Kurapati]

Currently the DWC3 driver supports only single port controller which
requires at most two PHYs ie HS and SS PHYs. There are SoCs that has
DWC3 controller with multiple ports that can operate in host mode.
Some of the port supports both SS+HS and other port supports only HS
mode.

This change primarily refactors the Phy logic in core driver to allow
multiport support with Generic Phy's.

Chananges have been tested on  QCOM SoC SA8295P which has 4 ports (2
are HS+SS capable and 2 are HS only capable).

Changes in v6:
Updated comments in code after.
Updated variables names appropriately as per review comments.
Updated commit text in patch-2 and added additional info as per review
comments.
The patch header in v5 doesn't have "PATHCH v5" notation present. Corrected
it in this version.

Changes in v5:
Added DT support for first port of Teritiary USB controller on SA8540-Ride
Added support for reading port info from XHCI Extended Params registers.

Changes in RFC v4:
Added DT support for SA8295p.

Changes in RFC v3:
Incase any PHY init fails, then clear/exit the PHYs that
are already initialized.

Changes in RFC v2:
Changed dwc3_count_phys to return the number of PHY Phandles in the node.
This will be used now in dwc3_extract_num_phys to increment num_usb2_phy 
and num_usb3_phy.

Added new parameter "ss_idx" in dwc3_core_get_phy_ny_node and changed its
structure such that the first half is for HS-PHY and second half is for
SS-PHY.

In dwc3_core_get_phy, for multiport controller, only if SS-PHY phandle is
present, pass proper SS_IDX else pass -1.

Link to v5: https://lore.kernel.org/all/20230310163420.7582-1-quic_kriskura@xxxxxxxxxxx/
Link to RFC v4: https://lore.kernel.org/all/20230115114146.12628-1-quic_kriskura@xxxxxxxxxxx/
Link to RFC v3: https://lore.kernel.org/all/1654709787-23686-1-git-send-email-quic_harshq@xxxxxxxxxxx/#r
Link to RFC v2: https://lore.kernel.org/all/1653560029-6937-1-git-send-email-quic_harshq@xxxxxxxxxxx/#r

Krishna Kurapati (8):
  dt-bindings: usb: Add bindings for multiport properties on DWC3
    controller
  usb: dwc3: core: Access XHCI address space temporarily to read port
    info
  usb: dwc3: core: Skip setting event buffers for host only controllers
  usb: dwc3: core: Refactor PHY logic to support Multiport Controller
  usb: dwc3: qcom: Add multiport controller support for qcom wrapper
  arm64: dts: qcom: sc8280xp: Add multiport controller node for SC8280
  arm64: dts: qcom: sa8295p: Enable tertiary controller and its 4 USB
    ports
  arm64: dts: qcom: sa8540-ride: Enable first port of tertiary usb
    controller

 .../devicetree/bindings/usb/snps,dwc3.yaml    |  13 +-
 arch/arm64/boot/dts/qcom/sa8295p-adp.dts      |  47 +++
 arch/arm64/boot/dts/qcom/sa8540p-ride.dts     |  22 ++
 arch/arm64/boot/dts/qcom/sc8280xp.dtsi        |  58 +++
 drivers/usb/dwc3/core.c                       | 373 ++++++++++++++----
 drivers/usb/dwc3/core.h                       |  71 +++-
 drivers/usb/dwc3/drd.c                        |  13 +-
 drivers/usb/dwc3/dwc3-qcom.c                  |  28 +-
 8 files changed, 523 insertions(+), 102 deletions(-)

-- 
2.40.0