Re: [PATCH] xhci-pci: Enable runtime PM on Alder Lake-N PCH xHCI controller

[Greg KH <gregkh@linuxfoundation.org>]

On Thu, Jul 14, 2022 at 09:06:44AM +0000, Kao, Ben wrote:
> > From: Greg KH <gregkh@linuxfoundation.org>
> > Sent: Tuesday, July 12, 2022 8:45 PM
> > To: Kao, Ben <ben.kao@intel.com>
> > Cc: Nyman, Mathias <mathias.nyman@intel.com>;
> > mathias.nyman@linux.intel.com; linux-usb@vger.kernel.org; linux-
> > kernel@vger.kernel.org
> > Subject: Re: [PATCH] xhci-pci: Enable runtime PM on Alder Lake-N PCH xHCI
> > controller
> > 
> > On Tue, Jul 12, 2022 at 08:24:42PM +0800, Ben Kao wrote:
> > > There are two Alder Lake-N xHCI host controllers with PCI IDs 0x464e
> > > and 0x54ed, now we add the quirk to default enable runtime PM for
> > > 0x54ed.
> > >
> > > Signed-off-by: Ben Kao <ben.kao@intel.com>
> > > ---
> > >  drivers/usb/host/xhci-pci.c | 2 ++
> > >  1 file changed, 2 insertions(+)
> > >
> > > diff --git a/drivers/usb/host/xhci-pci.c b/drivers/usb/host/xhci-pci.c
> > > index dce6c0ec8d34..44486156bd5d 100644
> > > --- a/drivers/usb/host/xhci-pci.c
> > > +++ b/drivers/usb/host/xhci-pci.c
> > > @@ -61,6 +61,7 @@
> > >  #define PCI_DEVICE_ID_INTEL_ALDER_LAKE_XHCI		0x461e
> > >  #define PCI_DEVICE_ID_INTEL_ALDER_LAKE_N_XHCI
> > 	0x464e
> > >  #define PCI_DEVICE_ID_INTEL_ALDER_LAKE_PCH_XHCI	0x51ed
> > > +#define PCI_DEVICE_ID_INTEL_ALDER_LAKE_N_PCH_XHCI	0x54ed
> > 
> > I think we ask this every time, but why don't we enable this for all devices
> > and then only disable it for the tiny number that don't need it?
> Got it, I will provide another patch to enable runtime PM by default for all
> Intel devices if no one has concerns.

Please test to verify that it works on the systems you enable it for and
verify that future devices will also work properly.

thanks,

greg k-h