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Date: Tue, 14 Jun 2011 17:50:13 +0200
From: Michael Jones <michael.jones@matrix-vision.de>
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CC: Laurent Pinchart <laurent.pinchart@ideasonboard.com>,
	Sakari Ailus <sakari.ailus@maxwell.research.nokia.com>
Subject: buffer index when streaming user-ptr buffers
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In the V4L2 spec, the description for v4l2_buffer.index says "This field
is only used for memory mapping I/O..."

However, in v4l-utils/contrib/capture-example.c, even user-pointer
buffers are indeed given a buf.index before being passed to VIDIOC_QBUF.
 And at least in the OMAP ISP driver, this information is relied upon in
QBUF regardless of V4L2_MEMORY_MMAP/USERPTR.  videobuf-core also uses
v4l2_buffer->index even if b->memory == V4L2_MEMORY_USERPTR.

Is this a bug in the OMAP driver and videobuf-core, and an unnecessary
assignment in capture-example?  Or is the V4L2 spec out of touch/ out of
date?

-Michael

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