On Mon June 4 2012 23:58:07 Hans Verkuil wrote: > Hi Rebecca, > > On Mon June 4 2012 21:34:23 Rebecca Schultz Zavin wrote: > > I have a system where the data is planar, but the kernel drivers > > expect to get one allocation with offsets for the planes. I can't > > figure out how to do that with the current dma_buf implementation. I > > thought I could pass the same dma_buf several times and use the > > data_offset field of the v4l2_plane struct but it looks like that's > > only for output. Am I missing something? Is this supported? > > v4l2_plane is typically used if the planes are allocated separately. > If you allocate it in one go, aren't the planes then at well-defined > offsets from the start? If so, then it is either one of the already > pre-defined planar formats found here: > > http://hverkuil.home.xs4all.nl/spec/media.html#yuv-formats > > or you define a pixelformat specific to your own hardware that identifies > that particular format. > > If it is one allocation, but there is no clear calculation based on width > and height that gives you the start of each plane, then we do not support > that at the moment. I believe I had a discussion about something similar > with people from Qualcomm, but that never came to anything. It took some digging, but this was the enhancement proposed for a Qualcomm problem: http://www.spinics.net/lists/linux-media/msg40376.html This may or may not be what you are looking for. Regards, Hans > > That would be something to discuss on the linux-media mailinglist. > > Regards, > > Hans > > _______________________________________________ > Linaro-mm-sig mailing list > Linaro-mm-sig@xxxxxxxxxxxxxxxx > http://lists.linaro.org/mailman/listinfo/linaro-mm-sig > -- 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
