On Saturday 01 July 2006 2:54 pm, Alan Stern wrote: > Here's my perspective on these matters, which is a little different from > David Brownell's.
Actually not that different ... mostly that UHCI doesn't separate the two types of schedule, and doesn't have a way to turn off processing either type without suspending the whole bus. Right? (That's stuff EHCI borrowed from the OHCI design.) For a more-different perspective, you could look at some of the OTG controllers that are built not by combining separate host, peripheral and OTG controllers, but by providing an all-in-one type controller. (These cost fewer transistors...) There a bunch of those around, and most of them don't seem to have been designed with the notion of an _integrated_ DMA engine ... so they're programmed more directly at the level of a FIFO. When the controller is packaged as a discrete chip there may be a way to couple a fifo to a third-party DMA unit through hardware handshake signals. More of the schedule traversal is managed by software than hardware. - Dave 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 _______________________________________________ linux-usb-devel@lists.sourceforge.net To unsubscribe, use the last form field at: https://lists.sourceforge.net/lists/listinfo/linux-usb-devel
