[PATCH 0/2] phy: amlogic: meson-g12a-usb2: add S4 support

[christian . koever-draxl]

From: Christian Stefan Kövér-Draxl <ckoever@xxxxxxxxxx>

The S4 USB2 PHY is the A1 design with different analog trims and an
extra disconnect threshold; without its PMA update bit the host sees no
root ports. Add a compatible and the S4 settings from the vendor driver.

Tested: both host ports enumerate keyboards, mice, hubs and storage.

Tool use (Documentation/process/generated-content.rst):
This work was done with the help of an AI coding assistant, Claude
(Anthropic), used through Claude Code over many sessions. It did a large
part of the hands-on work: it read the vendor kernel and the firmware
interfaces, probed registers on the board, drafted the code and the
changelogs, and ran the builds, checkpatch, dt_binding_check and the
tests on the hardware. I directed the work, reviewed every change and
the final patches, and take responsibility for them. There is no single
prompt to quote; the sessions were of the form "find out why X fails on
this board, fix it, test it on the box".

Tested on an Amediatech X98Q TV box (Amlogic S905W2, S4 family, 2 GiB),
vendor U-Boot and BL31/OP-TEE, Linux 7.3 plus this work.

Christian Stefan Kövér-Draxl (2):
  dt-bindings: phy: amlogic,g12a-usb2-phy: add S4 compatible
  phy: amlogic: meson-g12a-usb2: add S4 support

 .../bindings/phy/amlogic,g12a-usb2-phy.yaml   |  1 +
 drivers/phy/amlogic/phy-meson-g12a-usb2.c     | 65 ++++++++++++++-----
 2 files changed, 49 insertions(+), 17 deletions(-)


base-commit: 7be4bc52fd9e0e55dc9a2e0232b89427d2c4b614
-- 
2.56.0