Hi Andreas, I've just answered your private e-mail, here's a copy for the list.
On Friday 28 May 2010 11:08:19 Andreas Auer wrote: > Hi, > > I'm trying to get user pointer streaming with UVC webcams working. I > already got a patch from Laurent Pinchart (thanks) which enables user > pointer streaming. This patch works if I pass malloc()'d memory to the > driver. > My problem is that I want to use mmap()'d memory (via /dev/mem) and this > type of memory (flags VM_IO and VM_PFNMAP are set) is not supported to > be used with get_user_pages to map the memory to the kernel space. > > So, is there another way to map the pages into the kernel space to be > used for user pointer streaming?? I had a look at kmap (kmap_atomic)... > would this be possible?? PFNMAP memory has no page struct associated with it, it can't be handled the same way as regular main memory in the uvcvideo driver. The DSP driver probably reserves memory at system startup. That memory isn't managed by the Linux kernel memory manager. The uvcvideo driver doesn't support PFNMAP memory at the moment. That shouldn't be too difficult to fix though, but I'm afraid I don't have time to work on it right now. -- Regards, Laurent Pinchart _______________________________________________ Linux-uvc-devel mailing list [email protected] https://lists.berlios.de/mailman/listinfo/linux-uvc-devel
