On Tue, 21 Jun 2011 18:07:03 +0200 Marek Szyprowski <m.szyprowski@xxxxxxxxxxx> wrote: > I have an idea to introduce a new flags to let device driver tell vb2 > weather it supports 'streaming without buffers' or not. This way the > order of operations in vb2_streamon() function can be switched and vb2 > can also return an error if one will try to enable streaming on device > that cannot do it without buffers pre-queued. Do you really need a flag? If a driver absolutely cannot stream without buffers queued (and can't be fixed to start streaming for real when the buffers show up) it should just return -EINVAL from start_streaming() or some such. The driver must be aware of its limitations regardless, but there's no need to push that awareness into vb2 as well. (FWIW, I wouldn't switch the order of operations in vb2_streamon(); I would just take out the "if (q->streaming)" test at the end of vb2_qbuf() and pass the buffers through directly. But maybe that's just me.) Thanks, jon -- 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
