[RFC,0/2] media: platform: Add Aspeed Video Engine driver

Message

Eddie James Aug. 16, 2018, 7:43 p.m. UTC

The Video Engine (VE) embedded in the Aspeed AST2400 and AST2500 SOCs
can capture and compress video data from digital or analog sources. With
the Aspeed chip acting as a service processor, the Video Engine can
capture the host processor graphics output.

This series adds a V4L2 driver for the VE, providing a read() interface
only. The driver triggers the hardware to capture the host graphics output
and compress it to JPEG format.

Testing on an AST2500 determined that the videobuf/streaming/mmap interface
was significantly slower than the simple read() interface, so I have not
included the streaming part.

It's also possible to use an automatic mode for the VE such that
re-triggering the HW every frame isn't necessary. However this wasn't
reliable on the AST2400, and probably used more CPU anyway due to excessive
interrupts. It was approximately 15% faster.

Eddie James (2):
  dt-bindings: media: Add Aspeed Video Engine binding documentation
  media: platform: Add Aspeed Video Engine driver

 .../devicetree/bindings/media/aspeed-video.txt     |   25 +
 drivers/media/platform/Kconfig                     |    8 +
 drivers/media/platform/Makefile                    |    1 +
 drivers/media/platform/aspeed-video.c              | 1307 ++++++++++++++++++++
 4 files changed, 1341 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/media/aspeed-video.txt
 create mode 100644 drivers/media/platform/aspeed-video.c