Hello, On Wednesday, October 20, 2010 9:15 AM wrote: > On Wednesday, October 20, 2010 08:41:06 Marek Szyprowski wrote: > > Hello, > > > > As I promissed I continue the development of the VideoBuf2 at Samsung > > until Pawel finds some spare time to help us. This is a third version of > > the framework. Besides the minor bugfixes here and there I've added a > > complete read() callback emulator. This emulator provides 2 types of > > read() operation - 'streaming' and 'one shot'. It is suitable to replace > > both videobuf_read_stream() and videobuf_read_one() methods from the old > > videobuf. > > One thing I never understood: what is the point of supporting 'one shot' read > mode? Why not support just streaming? Does anyone know? I can imagine that some simple cameras that capture pure JPG frames might want to use 'one shot' mode. This enables easier scripting and things like 'cat /dev/video >capture.jpg' working. If you think that 'one shot' mode should be removed - let me know. > Another question: how hard is it to support write mode as well? I think > vb2 should support both. I suspect that once we have a read emulator it isn't > difficult to make a write emulator too. Well, that's possible. If you really think that write() emulator is also required, I can implement both. This shouldn't be much work. > A last remark: the locking has changed recently in videobuf due to the work > done on eliminating the BKL. It's probably a good idea to incorporate those > changes as well in vb2. Yes, I noticed that there are a lot of changes in for-2.6.37 staging tree, I will try to get through them and update relevant parts of vb2. The current version the vb2 patches is based on 2.6.36-rc8. Kernel tree with vb2 patches (and the required multiplane patches) will be available in a few hours on: http://git.infradead.org/users/kmpark/linux-2.6-samsung/shortlog/refs/heads/v4l/vb2 Best regards -- Marek Szyprowski Samsung Poland R&D Center -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
