Chipidea usb otg support for IMX/MXS (device functionality)

[Chen Peter-B29397]

> -----Original Message-----
> From: Marek Vasut [mailto:marex at denx.de]
> Sent: Sunday, July 07, 2013 9:10 AM
> To: Chen Peter-B29397
> Cc: shawn.guo at linaro.org; Michael Grzeschik; maxime.ripard at free-
> electrons.com; Hector Palacios; linux-usb at vger.kernel.org;
> s.hauer at pengutronix.de; alexander.shishkin at linux.intel.com; Estevam
> Fabio-R49496; Marc Kleine-Budde; m.grzeschik at pengutronix.de; linux-arm-
> kernel at lists.infradead.org
> Subject: Re: Chipidea usb otg support for IMX/MXS (device functionality)
> 
> Hi Peter,
> 
> > > Where can I measure this?
> > >
> > > > Two possible reasons:
> > > >
> > > > 1. You have not gpio control for vbus toggle when role switches.
> > >
> > > This works well.
> > >
> > > > 2. Your hardware has some problems that the vbus can't lower than
> 0.8v.
> > >
> > > How can I check that?
> >
> > Just measure the voltage of your otg vbus pin.
> 
> It's 2.5 volt for me. What am I supposed to observe happening there?
> 

http://marc.info/?l=linux-usb&m=137242465920952&w=2


Best regards,
Peter