Re: [PATCH v1 04/12] usb: phy: tegra: Support OTG mode programming

[Michał Mirosław]

On Thu, Jul 01, 2021 at 04:55:03PM +0300, Dmitry Osipenko wrote:
> 01.07.2021 05:23, Dmitry Osipenko пишет:
> >  static int tegra_usb_phy_init(struct usb_phy *u_phy)
> > @@ -967,12 +1057,26 @@ static int tegra_usb_phy_init(struct usb_phy *u_phy)
> >  			goto disable_vbus;
> >  	}
> >  
> > +	err = tegra_usb_phy_configure_pmc(phy);
> > +	if (err)
> > +		goto close_phy;
> > +
> >  	err = tegra_usb_phy_power_on(phy);
> >  	if (err)
> >  		goto close_phy;
> >  
> > +	if (phy->irq > 0) {
> > +		err = request_irq(phy->irq, tegra_usb_phy_isr, IRQF_SHARED,
> > +				  dev_name(phy->u_phy.dev), phy);
> > +		if (err)
> > +			goto pwr_off_phy;
> > +	}
> 
> There were reports that this patch was casing an unhandled USB interrupt
> event on some devices. I thought this problem was fixed already, but
> looking again at the offending kernel log again, it still should be a
> problem.
> 
> The interrupt fires from the usb_add_hcd() of the CI driver before CI
> driver have requested interrupt in ci_hdrc_probe(). So either CI driver
> should request interrupt earlier or Tegra PHY driver should keep shared
> interrupt disabled after requesting it, the latter variant should be
> more robust. I'll improve it in v2.

I'd suggest the first solution, as the latter is a workaround for what
is a normal shared interrupt behaviour. Maybe a controller reset is
needed in CI driver before going on with PHY init?

Best Regards
Michał Mirosław