Messages in this thread | | | Date | Tue, 17 Aug 2021 22:01:23 +0200 | From | Marc Kleine-Budde <> | Subject | Re: [PATCH v5 2/7] can: bittiming: allow TDC{V,O} to be zero and add can_tdc_const::tdc{v,o,f}_min |
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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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