On 17.08.2021 00:49:35, Vincent MAILHOL wrote:
> > We have 4 operations:
> > - tdc-mode off                  switch off tdc altogether
> > - tdc-mode manual tdco X tdcv Y configure X and Y for tdco and tdcv
> > - tdc-mode auto tdco X          configure X tdco and
> >                                 controller measures tdcv automatically
> > - /* nothing */                 configure default value for tdco
> >                                 controller measures tdcv automatically
> 
> The "nothing" does one more thing: it decides whether TDC should
> be activated or not.
> 
> > The /* nothing */ operation is what the old "ip" tool does, so we're
> > backwards compatible here (using the old "ip" tool on an updated
> > kernel/driver).
> 
> That's true but this isn't the real intent. By doing this design,
> I wanted the user to be able to transparently use TDC while
> continuing to use the exact same ip commands she or he is used
> to using.

Backwards compatibility using an old ip tool on a new kernel/driver must
work. In case of the mcp251xfd the tdc mode must be activated and tdcv
set to the automatic calculated value and tdco automatically measured.

Marc

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