Re: [RFC net PATCH v1] net: pcs: pcs-mtk-lynxi: fix bpi-r3 serdes configuration

Vladimir Oltean
2026-04-09T21:55:32Z

On Thu, Apr 09, 2026 at 03:33:42PM +0200, Frank Wunderlich wrote:
> From: Frank Wunderlich <frank-w@public-files.de>
>
> Commit 8871389da151 introduces common pcs dts properties which writes
> rx=normal,tx=normal polarity to register SGMSYS_QPHY_WRAP_CTRL of switch.
> This is initialized with tx-bit set and so change inverts polarity
> compared to before.
>
> It looks like mt7531 has tx polarity inverted in hardware and set tx-bit
> by default to restore the normal polarity.
>
> Till this patch the register write was only called when mediatek,pnswap
> property was set which cannot be done for switch because the fw-node param
> was always NULL from switch driver in the mtk_pcs_lynxi_create call.
>
> Do not configure switch side like it's done before.
>
> Fixes: 8871389da151 ("net: pcs: pcs-mtk-lynxi: deprecate "mediatek,pnswap"")
> Signed-off-by: Frank Wunderlich <frank-w@public-files.de>
> ---

Reviewed-by: Vladimir Oltean <vladimir.oltean@nxp.com>