[PATCH 06/21] usb: chipidea: Initialize and reinitialize phy later

Peter Chen hzpeterchen at gmail.com
Wed Jun 29 18:22:25 PDT 2016


On Wed, Jun 29, 2016 at 06:23:50PM -0700, Stephen Boyd wrote:
> Quoting Peter Chen (2016-06-28 19:30:52)
> > On Sun, Jun 26, 2016 at 12:28:23AM -0700, Stephen Boyd wrote:
> > > The ULPI phy on qcom platforms needs to be initialized and
> > > powered on after a USB reset and before we toggle the run/stop
> > > bit. Otherwise, the phy locks up and doesn't work properly.
> > 
> > This requirement is so strange, try to see if any other initialization
> > sequences.
> 
> I think the problem is that the reset bit also resets the phy because
> the phy is part of the same clock domain as the controller. Just a guess
> though.
> 
> >      
> > Since this driver is multi-platforms, I can't accept this change for
> > common, if you had to do that, would you please move your changes to
> > msm glue layer using CI_HDRC_CONTROLLER_RESET_EVENT and
> > CI_HDRC_CONTROLLER_STOPPED_EVENT? Besides, you need to add one flag
> > at ci_hdrc_platform_data.flags for your case to avoid normal
> > initialization.
> 
> Ok, let me see if I can make this work properly in the glue layer. I
> take it that you want me to add a flag for this specific case so that we
> don't do any phy control in the core and leave it up to the glue layer
> to handle, like CI_HDRC_DISABLE_PHY_CONTROL or something?

Yes

-- 

Best Regards,
Peter Chen



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