On Tue, Jun 24, 2014 at 08:51:43AM -0700, Chen, Alvin wrote: > From: Bryan O'Donoghue <bryan.odonoghue@xxxxxxxxx> > > This patch is to enable USB host controller for Intel Quark X1000. Add pci quirks > to adjust the packet buffer in/out threshold value, and ensure EHCI packet buffer > i/o threshold value is reconfigured to half. > > Signed-off-by: Bryan O'Donoghue <bryan.odonoghue@xxxxxxxxx> > Signed-off-by: Alvin (Weike) Chen <alvin.chen@xxxxxxxxx> > --- > drivers/usb/host/ehci-pci.c | 4 ++++ > drivers/usb/host/pci-quirks.c | 42 +++++++++++++++++++++++++++++++++++++++++ > drivers/usb/host/pci-quirks.h | 2 ++ > 3 files changed, 48 insertions(+) > > diff --git a/drivers/usb/host/ehci-pci.c b/drivers/usb/host/ehci-pci.c > index 3e86bf4..33cfa23 100644 > --- a/drivers/usb/host/ehci-pci.c > +++ b/drivers/usb/host/ehci-pci.c > @@ -50,6 +50,10 @@ static int ehci_pci_reinit(struct ehci_hcd *ehci, struct pci_dev *pdev) > if (!retval) > ehci_dbg(ehci, "MWI active\n"); > > + /* Reset the threshold limit */ > + if(unlikely(usb_is_intel_qrk(pdev))) Why unlikely()? Have you measured a speed difference here? And this is a _very_ slow path, what does that speed difference you measured help with? thanks, greg k-h -- 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
