Re: USB interrupt URB programming question
Alan Stern <[email protected]>
| Newsgroups | gmane.linux.usb.devel |
|---|---|
| Message-ID | <[email protected]> |
On Thu, 15 Feb 2007, Sven Anders wrote: > It constantly sent data, because the touchpad consist of temperature sensors > and the driver has to constantly save the current value to get precise > readings. I think that is the reason why the device did not stop sending > the data. > I tried to stop resubmitting (by NOT calling "usb_submit_urb" again) and I > hoped the the interrupt handler will continue when the touchpad is pressed > again, but it does not work. > A longer interval would solve it in some way: > I could get constantly new temperature update (each second or more) and if > the touchpad is touch, I can reduce the interval to the normal settings. It sounds like your completion handler should not call usb_submit_urb(). Instead you should use a kernel timer. When the timer expires, its callback routine should call usb_submit_urb(). The callback should also determine whether the touchpad is being pressed, use that information to decide how long the next timer interval will be, and restart the timer. Alan Stern ------------------------------------------------------------------------- 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