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SubjectRe: [GIT PATCH] USB autosuspend fixes for 2.6.23-rc6
On Thu, 13 Sep 2007, Alan Stern wrote:

> > Btw, this is in no way just an AUTOSUSPEND issue. The USB layer has a
> > *lot* of these quirks. They are often called "UNUSUAL_DEV()", but the
> > thing is, some of those things seem to be so usual that the naming is
> > dubious, and thus calling it a "quirk" or "unusual" is pretty dubious
> > too.
> You have concentrated your attention on the list for usb-storage,
> but the usbhid driver also has an impressively long quirks list.

This is true. First, there are HID_QUIRK_RDESC_* quirks, which we use to
fix up badly broken report descriptor of certain devices before it enters
the HID parser. There is nothing much we can do about them - these are
just workarounds for really broken devices that don't follow the HID
specification, but we can easily fix the things on the fly. Usually, these
devices are handled in Windows by specialized driver, but if we fix the
descriptor, we can use usbhid to handle them.

For the rest of the HID quirks -- most of them are also workarounds for
broken classess of devices. Usually, they claim to be HID-compliant device
in their file descriptor, but they do not follow the spec (they send
inverted axes values, send usage codes that violate the specification,
etc), but we can easily work around these bugs by a few lines of code and
let the devices to be handled by usbhid flawlessly. I guess this is worth
it.

Probably the only quirk entry that might be considered to be removed is
HID_QUIRK_NOGET, I'd say.

Thanks,

--
Jiri Kosina
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