Hi everybody, I'm investigating a hardware issue with a high-speed USB webcam. I would like to hack the EHCI driver to send no more than a single transaction per frame.
If I understand the big picture clearly, request are split into transactions, which are queued on a list accessible by the controller. I suppose that, once the queue is full, further transactions are queued on a software queue, are later copied to the hardware queue in the interrupt handler (or in a kernel thread waken up by the interrupt handler). If that's right, I'd like to hack the driver to queue a single transaction at once (basically assuming the queue length is one transaction), and wait until the next SOF before queuing the next one. Could anyone give me some pointers regarding how to do so ? I don't really care if it makes USB awfully slow, this is just a test. Cheers, Laurent Pinchart ------------------------------------------------------------------------- Using Tomcat but need to do more? Need to support web services, security? Get stuff done quickly with pre-integrated technology to make your job easier Download IBM WebSphere Application Server v.1.0.1 based on Apache Geronimo http://sel.as-us.falkag.net/sel?cmd=lnk&kid=120709&bid=263057&dat=121642 _______________________________________________ [email protected] To unsubscribe, use the last form field at: https://lists.sourceforge.net/lists/listinfo/linux-usb-devel
