[sane-devel] usb_clear_halt() in sanei_usb_read_int(), correct?

Rene Rebe rene at exactcode.de
Wed May 24 17:46:04 UTC 2006


On Wednesday 24 May 2006 02:24, Wittawat Yamwong wrote:
> Hi,
>
> Why is usb_clear_halt() called unconditionally when usb_interrupt_read()
> returns an error? A possible error can be -ETIMEDOUT for example and in
> this case there is no need to call usb_clear_halt(). I've a problem that
> interrupt packets get lost from time to time because of usb_clear_halt().
>
> I did a grep and it seems that only avision backend currently uses
> sanei_usb_read_int(). Will the backend still work if I modify the function
> so that it calls usb_clear_halt() if and only if a halt condition really
> occurred? (usb_interrupt_read() returns -EPIPE)

I think so (in fact I do not remeber I added the usb_clear_halt there -
cvs annotate or so could tell you).

Of hand I would say it is ok for the avision backend to wipe the call.

Yours,

-- 
René Rebe - Rubensstr. 64 - 12157 Berlin (Europe / Germany)
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