Re: USB interrupt URB programming question

Hello Alan!

On Wed, 14 Feb 2007, Sven Anders wrote:
>> After I called
>>         usb_fill_int_urb(dev->urb, udev,
>>                          usb_rcvintpipe(udev, int_in_endpointAddr),
>>                          dev->data, dev->datalen, atp_complete, dev, 1);
>>
>> the driver waits until the USB device (here the touchpad) starts sending
>> data (after I touched it). It does this continuously until I unload the
>> driver.
>
> Isn't that exactly what it's supposed to do?  What good is a driver if it
> doesn't wait for the device to send data?

Right, it waits, but I does not if I want it to wait...

>> If I change the driver to not (re)call the function
>>
>>          usb_submit_urb(dev->urb, GFP_ATOMIC);
>>
>> in the "atp_complete" function, it stops. But it does not wait (as the
>> first time) to restart the transfer. Is it possible to let the USB device
>> restart the transfer after I touched the pad again?
>
> Yes.  :-)
>
> Your question isn't clear.  It looks like you're asking how to restart the
> transfer.  The answer is obvious: Change the driver back so that it _does_
> call usb_submit_urb() inside atp_complete().

Yes will call the 'usb_submit_urb' in each invocation of the 'atp_complete'
function. And if I do this the 'atp_complete' function will be called
continuously.

My problem is: If I decide (upon the data I received from the touchpad), that
there isn't a finger any longer on the pad, I want to stop the calling of the
'atp_complete' function until I'm sure the touchpad is touched again. Then I
want the data again till it's released again.

After I suspend and resume the computer this works. How can I archive this
within the interrupt-handler-code?

Another possibility (for me) would be to make the interval (in the untouched
times)
longer. Is this possible?

Regards
 Sven

-- 
 Sven Anders <[email protected]>                 () Ascii Ribbon Campaign
                                                 /\ Support plain text e-mail
 ANDURAS service solutions AG
 Innstraße 71 - 94036 Passau - Germany
 Web: www.anduras.de - Tel: +49 (0)851-4 90 50-0 - Fax: +49 (0)851-4 90 50-55

Rechtsform: Aktiengesellschaft - Sitz: Passau - Amtsgericht Passau HRB 6032
Mitglieder des Vorstands: Sven Anders, Marcus Junker
Vorsitzender des Aufsichtsrats: Dipl. Kfm. Thomas Träger

-------------------------------------------------------------------------
Take Surveys. Earn Cash. Influence the Future of IT
Join SourceForge.net's Techsay panel and you'll get the chance to share your
opinions on IT & business topics through brief surveys-and earn cash
http://www.techsay.com/default.php?page=join.php&p=sourceforge&CID=DEVDEV
_______________________________________________
[email protected]
To unsubscribe, use the last form field at:
https://lists.sourceforge.net/lists/listinfo/linux-usb-devel