On Mon, 29 Feb 2016, Robert Dobrowolski wrote: > On BXT platform Host Controller and Device Controller figure as > same PCI device but with different device function. HCD should not > pass data to Device Controller. Checking if companion device is > Device Controller and omitting it. > > Signed-off-by: Robert Dobrowolski <robert.dobrowolski@xxxxxxxxx> > --- > drivers/usb/core/hcd-pci.c | 10 ++++++++++ > 1 file changed, 10 insertions(+) > > diff --git a/drivers/usb/core/hcd-pci.c b/drivers/usb/core/hcd-pci.c > index 9eb1cff..ae977d7 100644 > --- a/drivers/usb/core/hcd-pci.c > +++ b/drivers/usb/core/hcd-pci.c > @@ -74,6 +74,16 @@ static void for_each_companion(struct pci_dev *pdev, struct usb_hcd *hcd, > if (companion->bus != pdev->bus || > PCI_SLOT(companion->devfn) != slot) > continue; > + > + /* > + * On certain platforms Host Controller and Device Controller > + * figure as same device with different device function. HCD > + * should not pass data to Device Controller. Checking if > + * companion device is Device Controller and omitting it. > + */ > + if (companion->class == ((PCI_CLASS_SERIAL_USB << 8) | 0xfe)) > + continue; > + > companion_hcd = pci_get_drvdata(companion); > if (!companion_hcd || !companion_hcd->self.root_hub) > continue; This cries out for a #define. Besides, wouldn't it be safer to check that the class _is_ equal to CL_UHCI, CL_OHCI, or CL_EHCI instead of checking what the class _isn't_ equal to? What if somebody puts a non-USB function in the same slot? Alan Stern -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
