Re: USB interrupt URB programming question
Sven Anders <[email protected]>
| Newsgroups | gmane.linux.usb.devel |
|---|---|
| Organization | ANDURAS AG |
| Message-ID | <[email protected]> |
Alan Stern schrieb: > On Thu, 15 Feb 2007, Sven Anders wrote: > >> 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. Some idea I had myself. Is it possible to use a mix? My idea is as follows: Variant 1: If the completion handler decides, that there is no finger on the touchpad any more, it does not call usb_submit_urb() again. The completion handler stops. Via an kernel timer I will call the completion handler to test, if there is a finger on the touchpad again. If so, I will restart the interrupt handler and will call usb_submit_urb() until I have no finger on the pad again. Variant 2: If the is no finger on the touchpad, I will make the interval longer until I have a finger on the pad again... For variant 2 I want to know, if it is sufficent to set the 'interval' variable in the urb struct to a new value or do I have to call a function?! Regards Sven -- Sven Anders <[email protected]> () Ascii Ribbon Campaign /\ Support plain text e-mail ANDURAS service solutions AG Innstra?e 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 Tra"ger ------------------------------------------------------------------------- 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