Re: [PATCH net-next v4 1/2] net: phy: phy-c45: add SQI and SQI+ support for OATC14 10Base-T1S PHYs

[Andrew Lunn <andrew@lunn.ch>]

On Mon, Dec 01, 2025 at 08:53:45AM +0530, Parthiban Veerasooran wrote:
> Add support for reading Signal Quality Indicator (SQI) and enhanced SQI+
> from OATC14 10Base-T1S PHYs.
> 
> - Introduce MDIO register definitions for DCQ_SQI and DCQ_SQIPLUS.
> - Add `genphy_c45_oatc14_get_sqi_max()` to return the maximum supported
>   SQI/SQI+ level.
> - Add `genphy_c45_oatc14_get_sqi()` to return the current SQI or SQI+
>   value.
> - Update `include/linux/phy.h` to expose the new APIs.
> 
> SQI+ capability is read from the Advanced Diagnostic Features Capability
> register (ADFCAP). If SQI+ is supported, the driver calculates the value
> from the MSBs of the DCQ_SQIPLUS register; otherwise, it falls back to
> basic SQI (0-7 levels). This enables ethtool to report the SQI value for
> OATC14 10Base-T1S PHYs.
> 
> Open Alliance TC14 10BASE-T1S Advanced Diagnostic PHY Features
> Specification ref:
> https://opensig.org/wp-content/uploads/2025/06/OPEN_Alliance_10BASE-T1S_Advanced_PHY_features_for-automotive_Ethernet_V2.1b.pdf
> 
> Signed-off-by: Parthiban Veerasooran <parthiban.veerasooran@microchip.com>

Reviewed-by: Andrew Lunn <andrew@lunn.ch>

    Andrew