[v2,00/21] Add Tegra20 parallel video input capture

  Tegra20 and other Tegra SoCs have a video input (VI) peripheral that can
receive from either MIPI CSI-2 or parallel video (called respectively "CSI"
and "VIP" in the documentation). The kernel currently has a staging driver
for Tegra210 CSI capture. This patch set adds support for Tegra20 VIP
capture.

Unfortunately I had no real documentation available to base this work on.
I only had a working downstream 3.1 kernel, so I started with the driver
found there and heavily reworked it to fit into the mainline tegra-video
driver structure. The existing code appears written with the intent of
being modular and allow adding new input mechanisms and new SoCs while
keeping a unique VI core module. However its modularity and extensibility
was not enough to add Tegra20 VIP support, so I added some hooks to turn
hard-coded behaviour into per-SoC or per-bus customizable code. There are
also a fix, some generic cleanups and DT bindings.

Quick tour of the patches:

 * Device tree bindings and minor DTS improvements

   01. dt-bindings: display: tegra: add Tegra20 VIP
   02. dt-bindings: display: tegra: vi: add 'vip' property and example

 * A fix

   03. staging: media: tegra-video: fix .vidioc_enum_fmt_vid_cap to return all formats

 * Minor improvements to logging, comments, cleanups

   04. staging: media: tegra-video: improve documentation of tegra_video_format fields
   05. staging: media: tegra-video: document tegra_channel_get_remote_source_subdev
   06. staging: media: tegra-video: fix typos in comment
   07. staging: media: tegra-video: improve error messages
   08. staging: media: tegra-video: slightly simplify cleanup on errors
   09. staging: media: tegra-video: move private struct declaration to C file
   10. staging: media: tegra-video: remove unneeded include

 * Preparation to make the VI module generic enough to host Tegra20 and VIP

   11. staging: media: tegra-video: Kconfig: allow TPG only on Tegra210
   12. staging: media: tegra-video: move tegra_channel_fmt_align to a per-soc op
   13. staging: media: tegra-video: move default format to soc-specific data
   14. staging: media: tegra-video: move MIPI calibration calls from VI to CSI
   15. staging: media: tegra-video: add a per-soc enable/disable op
   16. staging: media: tegra-video: move syncpt init/free to a per-soc op
   17. staging: media: tegra-video: add syncpts for Tegra20 to struct tegra_vi
   18. staging: media: tegra-video: add hooks for planar YUV and H/V flip
   19. staging: media: tegra-video: add H/V flip controls

 * Implementation of VIP and Tegra20

   20. staging: media: tegra-video: add support for VIP (parallel video input)
   21. staging: media: tegra-video: add tegra20 variant

Enjoy!

Changed in v2:
- improved dt-bindings patches based on reviews
- removed patches 3 and 4 adding DT labels without a mainline user
- two small fixes to the last patch

[v1] https://lore.kernel.org/linux-tegra/20221124155634.5bc2a423@booty/T/#t

Luca

Luca Ceresoli (21):
  dt-bindings: display: tegra: add Tegra20 VIP
  dt-bindings: display: tegra: vi: add 'vip' property and example
  staging: media: tegra-video: fix .vidioc_enum_fmt_vid_cap to return
    all formats
  staging: media: tegra-video: improve documentation of
    tegra_video_format fields
  staging: media: tegra-video: document
    tegra_channel_get_remote_source_subdev
  staging: media: tegra-video: fix typos in comment
  staging: media: tegra-video: improve error messages
  staging: media: tegra-video: slightly simplify cleanup on errors
  staging: media: tegra-video: move private struct declaration to C file
  staging: media: tegra-video: remove unneeded include
  staging: media: tegra-video: Kconfig: allow TPG only on Tegra210
  staging: media: tegra-video: move tegra_channel_fmt_align to a per-soc
    op
  staging: media: tegra-video: move default format to soc-specific data
  staging: media: tegra-video: move MIPI calibration calls from VI to
    CSI
  staging: media: tegra-video: add a per-soc enable/disable op
  staging: media: tegra-video: move syncpt init/free to a per-soc op
  staging: media: tegra-video: add syncpts for Tegra20 to struct
    tegra_vi
  staging: media: tegra-video: add hooks for planar YUV and H/V flip
  staging: media: tegra-video: add H/V flip controls
  staging: media: tegra-video: add support for VIP (parallel video
    input)
  staging: media: tegra-video: add tegra20 variant

 .../display/tegra/nvidia,tegra20-vi.yaml      |  68 ++
 .../display/tegra/nvidia,tegra20-vip.yaml     |  63 ++
 MAINTAINERS                                   |  10 +
 drivers/staging/media/tegra-video/Kconfig     |   1 +
 drivers/staging/media/tegra-video/Makefile    |   2 +
 drivers/staging/media/tegra-video/csi.c       |  44 ++
 drivers/staging/media/tegra-video/tegra20.c   | 661 ++++++++++++++++++
 drivers/staging/media/tegra-video/tegra210.c  |  97 ++-
 drivers/staging/media/tegra-video/vi.c        | 321 ++-------
 drivers/staging/media/tegra-video/vi.h        |  76 +-
 drivers/staging/media/tegra-video/video.c     |   5 +
 drivers/staging/media/tegra-video/video.h     |   2 +-
 drivers/staging/media/tegra-video/vip.c       | 298 ++++++++
 drivers/staging/media/tegra-video/vip.h       |  72 ++
 14 files changed, 1434 insertions(+), 286 deletions(-)
 create mode 100644 Documentation/devicetree/bindings/display/tegra/nvidia,tegra20-vip.yaml
 create mode 100644 drivers/staging/media/tegra-video/tegra20.c
 create mode 100644 drivers/staging/media/tegra-video/vip.c
 create mode 100644 drivers/staging/media/tegra-video/vip.h
  

28.11.2022 18:23, Luca Ceresoli пишет:
> Tegra20 and other Tegra SoCs have a video input (VI) peripheral that can
> receive from either MIPI CSI-2 or parallel video (called respectively "CSI"
> and "VIP" in the documentation). The kernel currently has a staging driver
> for Tegra210 CSI capture. This patch set adds support for Tegra20 VIP
> capture.
> 
> Unfortunately I had no real documentation available to base this work on.
> I only had a working downstream 3.1 kernel, so I started with the driver
> found there and heavily reworked it to fit into the mainline tegra-video
> driver structure. The existing code appears written with the intent of
> being modular and allow adding new input mechanisms and new SoCs while
> keeping a unique VI core module. However its modularity and extensibility
> was not enough to add Tegra20 VIP support, so I added some hooks to turn
> hard-coded behaviour into per-SoC or per-bus customizable code. There are
> also a fix, some generic cleanups and DT bindings.
> 
> Quick tour of the patches:
> 
>  * Device tree bindings and minor DTS improvements
> 
>    01. dt-bindings: display: tegra: add Tegra20 VIP
>    02. dt-bindings: display: tegra: vi: add 'vip' property and example

This series adds the new DT node, but there are no board DTs in upstream
that will use VIP? Will we see the board patches?

In any case, given that you're likely the only one here who has access
to hardware with VIP, you should promote yourself to the tegra-video
driver maintainers and confirm that you will be able to maintain and
test this code for years to come.
  

Hello Dmitry,

thanks for your review.

On Tue, 20 Dec 2022 23:21:49 +0300
Dmitry Osipenko <digetx@gmail.com> wrote:

> 28.11.2022 18:23, Luca Ceresoli пишет:
> > Tegra20 and other Tegra SoCs have a video input (VI) peripheral that can
> > receive from either MIPI CSI-2 or parallel video (called respectively "CSI"
> > and "VIP" in the documentation). The kernel currently has a staging driver
> > for Tegra210 CSI capture. This patch set adds support for Tegra20 VIP
> > capture.
> > 
> > Unfortunately I had no real documentation available to base this work on.
> > I only had a working downstream 3.1 kernel, so I started with the driver
> > found there and heavily reworked it to fit into the mainline tegra-video
> > driver structure. The existing code appears written with the intent of
> > being modular and allow adding new input mechanisms and new SoCs while
> > keeping a unique VI core module. However its modularity and extensibility
> > was not enough to add Tegra20 VIP support, so I added some hooks to turn
> > hard-coded behaviour into per-SoC or per-bus customizable code. There are
> > also a fix, some generic cleanups and DT bindings.
> > 
> > Quick tour of the patches:
> > 
> >  * Device tree bindings and minor DTS improvements
> > 
> >    01. dt-bindings: display: tegra: add Tegra20 VIP
> >    02. dt-bindings: display: tegra: vi: add 'vip' property and example  
> 
> This series adds the new DT node, but there are no board DTs in upstream
> that will use VIP? Will we see the board patches?

I'm afraid I have no such plan. I don't have any public hardware with
Tegra20, with or without a parallel sensor. I have a custom board.

> In any case, given that you're likely the only one here who has access
> to hardware with VIP, 

Likely indeed.

> you should promote yourself to the tegra-video
> driver maintainers and confirm that you will be able to maintain and
> test this code for years to come.

I can definitely add myself as a maintainer of this driver and join the
maintenance effort, I'm adding that in v3. I also have a board that I
can permanently use for testing.