Re: [linux-usb-devel] [PATCH] USB BIOS early handoff only when the we the driver is configured

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]


On Tue, 31 Jul 2007, David Engraf wrote:

> 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
Please read the FAQ at

[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]
  Powered by Linux