RE: [PATCH net v2 1/1] net: fec: fix the PTP periodic output sysfs interface

[Wei Fang]

> > > I don't understand why you think that we should be exposing 4 channels
> > > to the user when they can only use one. And have the user guess which
> > > one should be programmed. Please explain (and Buday will have to update
> > > the commit message), to me v1 looked like a much better fix.
> >
> > As I explained in v1, I think the "channel index" parameter of
> > "/sys/class/ptp/ptp<N>/period" refers to the hardware channel number,
> > rather than the software mapping to the hardware channel.
> 
> Can you cite any documentation or examples?

There is no documentation that explicitly specifies whether it must be
the hardware channel or the software-defined channel. So this leads
to different people having different understandings of it.

> What would be the benefit of exposing the ID within the MAC IP (not
> even the board) to the user?

>From my perspective, I expect the "channel index" to be consistent with
"fsl,pps-channel" property, otherwise this may confuse some users.

Hi Buday,

If you want to revert to the first version, I suggest removing the check.
Because the check in period_store() already guarantees that
req.perout.index must be 0.