This series is actually food for our meetings at the Media Controller Summit ;)
It contains two patches that allows reusing the current media functions for control pipelines with should have entities, links, pads too, in a similar way to what's done to epresent the data pipeline.
I'm borrowing the ITU-T/IEEE nomenclature to describe the control elements. On ITU-T documents (also used by IETF on several Internet RFCs), there are 3 planes. We're actually using two of them:
- data plane: contains elements, functions and pipelines that handle the data traffic/streams;
- control plane: contains elements, functions and pipelines that handle the control of the elements of some infrastructure.
The approach taken is to add an extra field at the Kernel internal field specifying if an element/pad/link belongs to either data or control plane (or both).
Please notice that this RFC patches don't touch at the userspace API. There are several options that were discussed since December, 2014. Whatever done, we'll need to create support at MC. With this approach, the changes internally will be minimum and independent of whatever API we decide.
Please also notice that this is compile-tested only. Futher tests are needed.
Mauro Carvalho Chehab (2): media: add support for control entities/links/pads at MC media: Allow usage media_entity_graph_walk_next for control elements
drivers/media/media-device.c | 54 ++++++++++++++++--------- drivers/media/media-entity.c | 32 +++++++++++---- drivers/media/platform/exynos4-is/media-dev.c | 4 +- drivers/media/platform/omap3isp/isp.c | 6 +-- drivers/media/platform/omap3isp/ispvideo.c | 2 +- drivers/media/platform/vsp1/vsp1_video.c | 2 +- drivers/media/platform/xilinx/xilinx-dma.c | 2 +- drivers/staging/media/davinci_vpfe/vpfe_video.c | 6 +-- drivers/staging/media/omap4iss/iss.c | 6 +-- drivers/staging/media/omap4iss/iss_video.c | 4 +- include/media/media-entity.h | 54 ++++++++++++++++++++++++- 11 files changed, 130 insertions(+), 42 deletions(-)