[PATCH v2 0/3] phy: hdmi: Add FRL TxFFE level control

[Cristian Ciocaltea]

During HDMI 2.1 Fixed Rate Link training, the source and sink may
negotiate a Transmitter Feed Forward Equalizer (TxFFE) level to
compensate for signal quality degradation on the physical channel.  The
source starts at level 0 and may increment it up to a maximum agreed
upon during LTS3 in response to persistent link failures reported by the
sink.  TxFFE adjustment is optional and entirely independent of the FRL
rate and lane count selection.

Patch 1 extends the HDMI PHY configuration API with two new fields in
the frl sub-struct: ffe_level to carry the requested level, and a
set_ffe_level flag that switches the semantics of a phy_configure() call
to a pure equalizer update, leaving all other fields ignored.

Patch 2 addresses an issue with the PHY/PLL configuration after
reloading the samsung-hdptx kernel module.

Patch 3 implements the new interface in the Rockchip Samsung HDPTX PHY
driver.

Signed-off-by: Cristian Ciocaltea <cristian.ciocaltea@xxxxxxxxxxxxx>
---
Changes in v2:
- Added a new patch to fix samsung-hdptx PHY config after module reload
- Rebased series onto v7.3-rc1 and dropped the dependency on the "Clock
  fixes and API transition cleanups" PHY series which already landed
- Link to v1: https://lore.kernel.org/r/20260328-hdptx-ffe-v1-0-53ebd5dea20a@xxxxxxxxxxxxx

---
Cristian Ciocaltea (3):
      phy: hdmi: Add optional FRL TxFFE config options
      phy: rockchip: samsung-hdptx: Handle PHY config after module reload
      phy: rockchip: samsung-hdptx: Add support for FRL TxFFE level control

 drivers/phy/rockchip/phy-rockchip-samsung-hdptx.c | 80 +++++++++++++++++++++--
 include/linux/phy/phy-hdmi.h                      |  6 ++
 2 files changed, 79 insertions(+), 7 deletions(-)
---
base-commit: cee9395acd8043be0644b25c34bfa86623f2b935
change-id: 20260328-hdptx-ffe-a89c51e66904