Re: [Libusb-devel] Patch: libusb/os/linux_usbfs.c: Distingush between usbfs and other kernel mode drivers

[Xiaofan C. <xia...@gm...>]

On Wed, Oct 6, 2010 at 4:31 PM, Peter Stuge <pe...@st...> wrote:
>> Still I am not that convinced that "usbfs" is really a kernel driver,
>
> What would convince you?

If the Linux kernel USB developer like Alan Stern or Greg KH
say so, I would be convinced.

If there is a kernel driver attached to the USB device (an interface),
then libusb_claim_interface() should fail. And this is consistent
with my view that "usbfs" is not a kernel driver in the context
of libusb.

>> at least not in the typically meaning of "driver", rather it is
>> part of the USB core which is exposed to the user space.
>
> It *is* a separate driver. Sure it's not like the others in some
> ways, because it can be bound to any interface, and because it offers
> ioctls on the device files to userspace, but inside it uses exactly
> the same URB calls as kernel USB device drivers.
>
> It is really analogous to libusb0.sys in Windows.
>

Totally different. If I need to use libusb0.sys, then I need to
attach it to the device (as a device driver or a filter).

-- 
Xiaofan