Re: [9fans] new usb stack and implicit timeouts

[Gorka Guardiola <paurea@gmail.com>]

On Sun, Jul 19, 2009 at 5:58 PM, Francisco J Ballesteros<nemo@lsub.org> wrote:
> On Sun, Jul 19, 2009 at 5:46 PM, <cinap_lenrek@gmx.de> wrote:
>> http://www.beyondlogic.org/usbnutshell/usb6.htm#SetupPacket
>>
>
> IIRC, I think the host controller is responsible for timing out
> requests sent to the device (I refer to setup packets), but my uchi
> does not. In any case, I don't think anyone wants to remove timeouts
> from ctl requests.
>
>

I am unsure I would remove timeouts even from bulk endpoints.
It is true that some devices (the usb/serial for example) need to
read for an undefined time waiting for data, but I don't think that is
an issue as long
as the timeouts are long enough, doing polling is quite easy. There is
polling in the
lower levels anyway.

On the other hand, I think smart card readers go for
lunch on a read and may never come
back if there is no timeout. Of course alarm() can be used, but
a timeout makes it simpler. I prefer having to poll on some
cases than having to use signals on others.

--
- curiosity sKilled the cat