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 Or is the V4L2 spec out of touch/ out of date?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 MATRIX VISION GmbH, Talstrasse 16, DE-71570 Oppenweiler Registergericht: Amtsgericht Stuttgart, HRB 271090 Geschaeftsfuehrer: Gerhard Thullner, Werner Armingeon, Uwe Furtner -- 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