> > The doc in patch 1 says : > > > > > + * Link-wide mode: > > > + * - Some PHYs only expose a link-wide aggregate MSE, or cannot map their > > > + * measurement to a specific channel/pair (e.g. 100BASE-TX when MDI/MDI-X > > > + * resolution is unknown). In that case, callers must use the LINK selector. > > > > The way I understand that is that PHYs will report either channel-specific values or > > link-wide values. Is that correct or are both valid ? In BaseT1 this is the same thing, > > but maybe for consistency, we should report either channel values or link-wide values ? > > for 100Base-T1 the LINK and channel-A selectors are effectively the > same, since the PHY only has a single channel. In this case both are > valid, and the driver will return the same answer for either request. > > I decided to expose both for consistency: > - on one side, the driver already reports pair_A information for the > cable test, so it makes sense to allow channel-A here as well; > - on the other side, if a caller such as a generic link-status/health > request asks for LINK, we can also provide that without special > casing. > > So the driver just answers what it can. For this PHY, LINK and > channel-A map to the same hardware register, and all other selectors > return -EOPNOTSUPP. The document you referenced explicitly says it is for 100BASE-T1. Are there other Open Alliance documents which extend the concept to -T2 and -T4 links? Do you have access to -T2 or -T4 PHYs which implement the concept for multiple pairs? I think it is good you are thinking about the API, how it could work with -T2 and -T4, but do we need this complexity now? Andrew
