On Tue, 31 Jul 2007, David Engraf wrote:
> When CONFIG_USB_UHCI_HCD, CONFIG_USB_OHCI_HCD or CONFIG_USB_EHCI_HCD is
> not configured we don't need to call the quirk_usb_handoff_xxxx function
> in driver/usb/host/pci_quiks.c.
>
> I think the kernel shouldn't take the control over the usb controller
> when we don't have the driver for it,
> so with this patch the kernel takes the control only when the driver is
> configured.
Have you found a system where this really improves behavior or is it
just theoretical?
There _is_ a theoretical reason for running the handoff routines even
when the corresponding driver isn't configured. Namely, at startup the
controller will be in some undetermined state as a result of usage by
the firmware. Resetting it to a known idle state is a good idea.
Bear in mind that on some systems, not performing the handoff has
caused interrupt storms during startup.
Alan Stern
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [email protected]
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
[Index of Archives]
[Kernel Newbies]
[Netfilter]
[Bugtraq]
[Photo]
[Stuff]
[Gimp]
[Yosemite News]
[MIPS Linux]
[ARM Linux]
[Linux Security]
[Linux RAID]
[Video 4 Linux]
[Linux for the blind]
[Linux Resources]
