RE: dwc3 PHY autosuspend feature

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Sorry for replying to myself, but I forgot to answer one question: No,
PHY autosuspend is not an optional feature, every core since 1.94a
has it.

-- 
Paul

> From: Paul Zimmerman
> Sent: Wednesday, March 06, 2013 11:23 AM
> 
> > From: Felipe Balbi [mailto:balbi@xxxxxx]
> > Sent: Wednesday, March 06, 2013 2:36 AM
> >
> > Hi Paul,
> >
> > Kishon has uncovered a possible 'situation' with dwc3 which we need to
> > clear up.
> >
> > According to your commit 802fde98 (usb: dwc3: support new revisions of
> > DWC3 core), we don't need to suspend/resume the PHYs at all with any
> > version > 1.94a, but what we observe is that SUSPHY bits are never set.
> >
> > What does that mean ? Would PHY autosuspend be an optional feature by
> > any chance ? Also, I can't find anywhere in the databook saying that
> > fiddling with SUSPHY should be avoided due to core IP controlling that
> > automatically.
> >
> > Can you enlighten us ?
> 
> You still need to set the SusPHY bits, but you only need to do it once.
> After that, the core will take care of suspending/resuming the PHYs
> at the right time. You will not see the SusPHY bits changing, though.
> 
> Actually, for GUSB2PHYCFG.SusPHY you can't just set it once. You
> need to clear it before any register operation that is marked in the
> databook with the note "If GUSB2PHYCFG[6] is set to '1', it must be
> set to '0' prior to issuing this command and may be set to '1' after
> the command completes". Then when the operation completes
> you can set it back to 1.
> 
> --
> Paul

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