V4L/DVB (9804): cx18: Avoid making firmware API calls with the queue lock held

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cx18: Avoid making firmware API calls with the queue lock held.  The source
of MPEG strem corruption when not holding the queue lock was found to be that
the MPEG buffer could be retrieved by the user app before it was sync'ed for
the host cpu.  Incoming buffers are now sync'ed before being put on q_full and
releasing the queue lock.  We can thus avoid the sometimes lengthy call to
the firmware for CPU_DE_SET_MDL while holding the queue lock, so we can get
better performance.

Signed-off-by: Andy Walls <awalls@radix.net>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

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This commit is contained in:

Andy Walls 2008-12-12 15:50:27 -03:00 • committed by Mauro Carvalho Chehab

parent 765f6f612e

commit abb096de82

4 changed files with 30 additions and 37 deletions

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15

drivers/media/video/cx18/cx18-mailbox.c

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13

drivers/media/video/cx18/cx18-queue.c

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35

drivers/media/video/cx18/cx18-streams.c

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2

drivers/media/video/cx18/cx18-streams.h

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