Re: [PATCH 0/2] musb-fixes for v4.9-rc2

[Tony Lindgren <tony-4v6yS6AI5VpBDgjK7y7TUQ@public.gmane.org>]

* Ladislav Michl <ladis-6z/3iImG2C8G8FEW9MqTrA@public.gmane.org> [161104 02:47]:
> On Fri, Nov 04, 2016 at 10:31:38AM +0200, Felipe Balbi wrote:
> [snip]
> > Sounds like VBUS dropping to me. Remember, MUSB is really anal about
> > VBUS levels. If it drops enough for the PHY to report one of those 4
> > VBUS levels, then MUSB just gives up.
> > 
> > What we used to do back at Nokia was disable reporting of some of those
> > VBUS levels at the PHY driver.

Yeah that seems to be what Ladis is seeing.

> Well, I was getting these even without anything connected to musb:
> [ 1526.594696] musb-hdrc musb-hdrc.0.auto: VBUS_ERROR in a_idle (90, <VBusValid), retry #0, port1 00000104
> [  485.244781] musb-hdrc musb-hdrc.0.auto: VBUS_ERROR in a_idle (90, <VBusValid), retry #0, port1 00000104
> ...and with the hub connected:
> [  562.803833] musb-hdrc musb-hdrc.0.auto: VBUS_ERROR in a_idle (90, <VBusValid), retry #0, port1 00000507
> [   50.068664] musb-hdrc musb-hdrc.0.auto: VBUS_ERROR in a_idle (90, <VBusValid), retry #0, port1 00000507
> And indeed, after these errors musb gives up.
> 
> However these are gone with Tony's last patch. Bisecting now, approx 6 iterations left.

These were caused by devctl session bit taking few seconds to clear
so we have to poll that on disconnect until it clears.

Regards,

Tony
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