Re: [PATCH v2 2/2] PCI: Override Synopsys USB 3.x HAPS device class

[Trent Piepho <tpiepho@impinj.com>]

On Mon, 2019-02-04 at 23:18 +0000, Thinh Nguyen wrote:
> Trent Piepho wrote:
> > On Mon, 2018-12-10 at 14:08 -0800, Thinh Nguyen wrote:
> > > Synopsys USB 3.x host HAPS platform has a class code of
> > > PCI_CLASS_SERIAL_USB_XHCI, and xhci driver can claim it. However, these
> > > devices should use dwc3-haps driver. Change these devices' class code to
> > > PCI_CLASS_SERIAL_USB_DEVICE to prevent the xhci-pci driver from claiming
> > > them.
> > > 
> > This change breaks my IMX7d based device.  This SoC has a PCIe bus
> > based on the Synopsys Designware host controller.  This has a root
> >                                                  
> > 
> Right. Lukas also reported this. It appears that there's a duplicate VID
> PID used for the USB controller on HAPS platform. You can review the
> discussion subject "Linux Kernel Regression: HAPS quirk breaks PCIe on
> i.MX6QP".
> 
> -DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_SYNOPSYS, PCI_ANY_ID,
> -                        quirk_synopsys_haps);
> +DECLARE_PCI_FIXUP_CLASS_HEADER(PCI_VENDOR_ID_SYNOPSYS, PCI_ANY_ID,
> +               PCI_CLASS_SERIAL_USB_XHCI, 0, quirk_synopsys_haps);

Thanks for the quick response.  Tested this on imx7d, and as expected,
it fixes the problem.  The host bridge has class PCI_CLASS_BRIDGE_PCI
like it should and the quirk no longer matches.