Re: [PATCH net-next v1 1/1] net: phy: dp83tg720: Add cable testing support

[Andrew Lunn]

On Wed, Aug 07, 2024 at 11:32:51AM +0200, Oleksij Rempel wrote:
> Introduce cable testing support for the DP83TG720 PHY. This implementation
> is based on the "DP83TG720S-Q1: Configuring for Open Alliance Specification
> Compliance (Rev. B)" application note.

Does the OA specification describe all these registers? Should we
expect other devices to be identical?

> +/**
> + * dp83tg720_get_fault_type - Convert TDR fault type to ethtool result code.
> + * @fault_type: Fault type value from the PHY.
> + *
> + * Returns: Corresponding ethtool result code.
> + */
> +static int dp83tg720_get_fault_type(int fault_type)
> +{
> +	switch (fault_type) {
> +	case DP83TG720S_TDR_FAULT_TYPE_SHORT:
> +		return ETHTOOL_A_CABLE_RESULT_CODE_SAME_SHORT;
> +	case DP83TG720S_TDR_FAULT_TYPE_OPEN:
> +		return ETHTOOL_A_CABLE_RESULT_CODE_OPEN;
> +	case DP83TG720S_TDR_FAULT_TYPE_NOISE:
> +		return ETHTOOL_A_CABLE_RESULT_CODE_UNSPEC;

You could add a new type for this. I think some implementations will
also re-try a few times to see if a quiet period can be found.

	Andrew