Re: [PATCH net-next 2/3] dt-bindings: net: micrel: Configure latency values and timestamping check for LAN8814 phy

Andrew Lunn
2022-03-12T20:04:49Z

> PTP4l(8) System Manager's Manual PTP4l(8)
>
> NAME
> ptp4l - PTP Boundary/Ordinary/Transparent Clock
>
> ...
>
> egressLatency
> Specifies the difference in nanoseconds between the actual
> transmission time at the reference plane and the reported trans‐
> mit time stamp. This value will be added to egress time stamps
> obtained from the hardware. The default is 0.
>
> ingressLatency
> Specifies the difference in nanoseconds between the reported re‐
> ceive time stamp and the actual reception time at reference
> plane. This value will be subtracted from ingress time stamps
> obtained from the hardware. The default is 0.
>

Hi Richard

Do these get passed to the kernel so the hardware can act on them, or
are they used purely in userspace by ptp4l?

If they has passed to the kernel, could we provide a getter as well as
a setter, so the defaults hard coded in the driver can be read back?

Andrew