On Thu, 2012-03-15 at 22:39 +0800, Alex Shi wrote: > > > > This is not a good idea. What happens if some USB-3 controller > > (perhaps a non-xHCI USB-3 controller) doesn't use MSI? > > > > > current usb3 driver just xhci. but sure it need to modify if non-xhci > usb pops up. > > > The right way to avoid registering a legacy interrupt handler is to > > call usb_add_hcd() with irqnum equal to 0. > > > a good trick! will try it tomorrow. Do you mean the following patch? It tested. :) ------------ >From 5ae9a6fe88752495af6da6182cad26620f1ab190 Mon Sep 17 00:00:00 2001 From: Alex Shi <alex.shi@xxxxxxxxx> Date: Thu, 15 Mar 2012 08:12:47 +0800 Subject: [PATCH] usb/core: skip unnecessary line IRQ request for USB3 USB3(only xhci driver) requests line IRQ here but will disable it in later driver->start function and try MSI first: xhci_hcd 0000:02:00.0: irq 18, io mem 0xfe500000 xhci_hcd 0000:02:00.0: irq 45 for MSI/MSI-X xhci_hcd 0000:02:00.0: irq 46 for MSI/MSI-X So it is better to remove the redundant request here. Signed-off-by: Alex Shi <alex.shi@xxxxxxxxx> --- drivers/usb/core/hcd-pci.c | 5 ++++- drivers/usb/host/xhci.c | 3 --- 2 files changed, 4 insertions(+), 4 deletions(-) diff --git a/drivers/usb/core/hcd-pci.c b/drivers/usb/core/hcd-pci.c index 81e2c0d..7b73c74 100644 --- a/drivers/usb/core/hcd-pci.c +++ b/drivers/usb/core/hcd-pci.c @@ -245,7 +245,10 @@ int usb_hcd_pci_probe(struct pci_dev *dev, const struct pci_device_id *id) pci_set_master(dev); - retval = usb_add_hcd(hcd, dev->irq, IRQF_SHARED); + if ((driver->flags & HCD_MASK) != HCD_USB3) + retval = usb_add_hcd(hcd, dev->irq, IRQF_SHARED); + else + retval = usb_add_hcd(hcd, 0, IRQF_SHARED); if (retval != 0) goto unmap_registers; set_hs_companion(dev, hcd); diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c index c939f5f..64979c2 100644 --- a/drivers/usb/host/xhci.c +++ b/drivers/usb/host/xhci.c @@ -338,9 +338,6 @@ static int xhci_try_enable_msi(struct usb_hcd *hcd) if (xhci->quirks & XHCI_BROKEN_MSI) return 0; - /* unregister the legacy interrupt */ - if (hcd->irq) - free_irq(hcd->irq, hcd); hcd->irq = -1; ret = xhci_setup_msix(xhci); -- 1.6.3.3 > > > > > 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
