em28xx: fix buffer underrun handling

This patch fixes three related issues and a fourth trivial one:

- Use buffers even if no-one's currently waiting for them (fixes
underrun issues);

- Don't return incomplete/mangled frames at the start of streaming and
in the case of buffer underruns;

- Fix an issue which could cause the driver to write to a buffer that's
been freed after videobuf_queue_cancel is called (exposed by the
previous two fixes - for some reason, ignoring buffers that weren't
being waited on worked around the issue);

- Fix a bug which could cause only one field to be filled in the first
buffer (or first few buffers) after streaming is started.

Signed-Off-By: Aidan Thornton <makosoft@googlemail.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>

0 files changed, 0 insertions, 0 deletions