On Thu, Jul 01, 2010 at 06:37:32PM +0200, ext Gadiyar, Anand wrote:
Gupta, Ajay Kumar wrote:
> > >> actualy, should be UHH_SYSCONFIG:SOFTRESET.
> > >
> > >That would reset the controller and so all the register would get
> > >their default values.
> >
> > aa, ok. I mis-read, you want to reset the PHY only. Still, the boards
> > without the reset line, won't work, so a better solution (if any) has to
> > be found.
>
> I agree.
>
> >
> > Maybe driving port reset signal would make PHY act ?
> >
> Do you mean to reset PHY using PHY reset command over ULPI ?
> Anyways would try this.
Soft resetting the PHY also fixes the issue. Here is the version-2 of
This patch.
-Ajay
-------- cut here -------------
Currently devices don't get detected automatically if the ehci
module is inserted 2nd time onward. We need to disconnect and
reconnect the device for it to get detected and enumerated.
Resetting the USB PHY using PHY reset command over ULPI fixes
this issue. Tested on OMAP3EVM.
Ajay,
I don't currently understand why this is needed. I see that this
fixes a problem for you, but I do not understand why it works.
I would like to test this on the other PHYs that could interface
with the OMAP3 before acking this. I don't have access to them
right now, and I'll try and dig up those boards on Monday and give
it a spin.
I don't think there's a problem with this, take a look at Section 3.5
Power on and Reset from ULPI spec:
"After power-up, and when the clock starts toggling, the Link must reset
the PHY by writing to the Reset bit in the Function Control register.
When this bit is set, the transceiver will assert dir and reset the
digital core.
When the reset completes, the PHY de-asserts dir and automatically
clears the Reset bit in the Function Control register. After
de-asserting dir, the PHY must immediately re-assert dir and send an RX
CMD update to the Link."
So, we _do_ need to reset the PHY when probing ehci-hcd, and should
probably assert SUSPENDM when rmmoding it.
--
balbi
DefectiveByDesign.org
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