Re: [PATCH v5] usb: host: xhci-plat: Set XHCI_SKIP_PHY_INIT quirk for DWC3 controller

[Greg Kroah-Hartman <gregkh@linuxfoundation.org>]

On Mon, Jan 24, 2022 at 11:01:07AM +0530, Sandeep Maheswaram wrote:
> Hi Greg,
> 
> On 1/7/2022 10:27 AM, Sandeep Maheswaram wrote:
> > 
> > On 1/6/2022 7:55 PM, Greg Kroah-Hartman wrote:
> > > On Wed, Dec 22, 2021 at 11:39:43AM +0530, Sandeep Maheswaram wrote:
> > > > Set XHCI_SKIP_PHY_INIT quirk to avoid phy initialization twice.
> > > > Runtime suspend of phy drivers was failing from DWC3 driver as runtime
> > > > usage value is 2 because the phy is initialized from DWC3 and HCD core.
> > > > DWC3 manages phy in their core drivers. Set this quirk to avoid phy
> > > > initialization in HCD core.
> > > > 
> > > > Signed-off-by: Sandeep Maheswaram <quic_c_sanm@quicinc.com>
> > > > ---
> > > > v5:
> > > > Added comment to explain the change done.
> > > > v4:
> > > > Changed pdev->dev.parent->of_node to sysdev->of_node
> > > > 
> > > >   drivers/usb/host/xhci-plat.c | 8 ++++++++
> > > >   1 file changed, 8 insertions(+)
> > > > 
> > > > diff --git a/drivers/usb/host/xhci-plat.c
> > > > b/drivers/usb/host/xhci-plat.c
> > > > index c1edcc9..e6014d4 100644
> > > > --- a/drivers/usb/host/xhci-plat.c
> > > > +++ b/drivers/usb/host/xhci-plat.c
> > > > @@ -327,6 +327,14 @@ static int xhci_plat_probe(struct
> > > > platform_device *pdev)
> > > >                        &xhci->imod_interval);
> > > >       }
> > > >   +    /*
> > > > +     * Set XHCI_SKIP_PHY_INIT quirk to avoid phy initialization twice.
> > > > +     * DWC3 manages phy in their core drivers. Set this quirk
> > > > to avoid phy
> > > > +     * initialization in HCD core.
> > > > +     */
> > > > +    if (of_device_is_compatible(sysdev->of_node, "snps,dwc3"))
> > > > +        xhci->quirks |= XHCI_SKIP_PHY_INIT;
> > > > +
> > > Why is this function caring about dwc3 stuff?  Shoudn't this be a
> > > "generic" device property instead of this device-specific one?
> > > 
> > > thanks,
> > > 
> > > greg k-h
> > 
> > This quirk is set only if required for some controllers (eg: dwc3 &
> > cdns3).
> > 
> > Please check below commit.
> > 
> > https://lore.kernel.org/all/20200918131752.16488-5-mathias.nyman@linux.intel.com/
> > 
> > 
> > 
> > Regards
> > 
> > Sandeep
> > 
> > 
> Please let me know if anything more info needed for this patch.

The merge window ended a few hours ago, give me a few days to catch up
with my pending email queue that I have to review:

$ mdfrm -c ~/mail/todo/
2254 messages in /home/gregkh/mail/todo/

thanks,

greg k-h