[PATCH v2 0/3] phy: hdmi: Add FRL TxFFE level control
From: Cristian Ciocaltea <hidden>
Date: 2026-09-01 19:57:42
Also in:
linux-phy, linux-rockchip, lkml
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 <redacted> --- 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@collabora.com (local) --- 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