[PATCH v3 00/22] Associate ddc adapters with connectors

[Daniel Vetter]

On Fri, Jun 28, 2019 at 06:01:14PM +0200, Andrzej Pietrasiewicz wrote:
> It is difficult for a user to know which of the i2c adapters is for which
> drm connector. This series addresses this problem.
> 
> The idea is to have a symbolic link in connector's sysfs directory, e.g.:
> 
> ls -l /sys/class/drm/card0-HDMI-A-1/ddc
> lrwxrwxrwx 1 root root 0 Jun 24 10:42 /sys/class/drm/card0-HDMI-A-1/ddc \
> 	-> ../../../../soc/13880000.i2c/i2c-2
> 
> The user then knows that their card0-HDMI-A-1 uses i2c-2 and can e.g. run
> ddcutil:
> 
> ddcutil -b 2 getvcp 0x10
> VCP code 0x10 (Brightness                    ): current value =    90, max value =   100
> 
> The first patch in the series adds struct i2c_adapter pointer to struct
> drm_connector. If the field is used by a particular driver, then an
> appropriate symbolic link is created by the generic code, which is also added
> by this patch.
> 
> The second patch is an example of how to convert a driver to this new scheme.
> 
> v1..v2:
> 
> - used fixed name "ddc" for the symbolic link in order to make it easy for
> userspace to find the i2c adapter
> 
> v2..v3:
> 
> - converted as many drivers as possible.
> 
> PATCHES 3/22-22/22 SHOULD BE CONSIDERED RFC!

There's a lot more drivers than this I think (i915 is absent as an
example, but there should be tons more). Why are those not possible?
-Daniel

> 
> Andrzej Pietrasiewicz (22):
>   drm: Include ddc adapter pointer in struct drm_connector
>   drm/exynos: Provide ddc symlink in connector's sysfs
>   drm: rockchip: Provide ddc symlink in rk3066_hdmi sysfs directory
>   drm: rockchip: Provide ddc symlink in inno_hdmi sysfs directory
>   drm/msm/hdmi: Provide ddc symlink in hdmi connector sysfs directory
>   drm/sun4i: hdmi: Provide ddc symlink in sun4i hdmi connector sysfs
>     directory
>   drm/mediatek: Provide ddc symlink in hdmi connector sysfs directory
>   drm/tegra: Provide ddc symlink in output connector sysfs directory
>   drm/imx: imx-ldb: Provide ddc symlink in connector's sysfs
>   drm/imx: imx-tve: Provide ddc symlink in connector's sysfs
>   drm/vc4: Provide ddc symlink in connector sysfs directory
>   drm: zte: Provide ddc symlink in hdmi connector sysfs directory
>   drm: zte: Provide ddc symlink in vga connector sysfs directory
>   drm/tilcdc: Provide ddc symlink in connector sysfs directory
>   drm: sti: Provide ddc symlink in hdmi connector sysfs directory
>   drm/mgag200: Provide ddc symlink in connector sysfs directory
>   drm/ast: Provide ddc symlink in connector sysfs directory
>   drm/bridge: dumb-vga-dac: Provide ddc symlink in connector sysfs
>     directory
>   drm/bridge: dw-hdmi: Provide ddc symlink in connector sysfs directory
>   drm/bridge: ti-tfp410: Provide ddc symlink in connector sysfs
>     directory
>   drm/amdgpu: Provide ddc symlink in connector sysfs directory
>   drm/radeon: Provide ddc symlink in connector sysfs directory
> 
>  .../gpu/drm/amd/amdgpu/amdgpu_connectors.c    | 70 +++++++++++-----
>  drivers/gpu/drm/ast/ast_mode.c                |  1 +
>  drivers/gpu/drm/bridge/dumb-vga-dac.c         | 19 ++---
>  drivers/gpu/drm/bridge/synopsys/dw-hdmi.c     | 40 ++++-----
>  drivers/gpu/drm/bridge/ti-tfp410.c            | 19 ++---
>  drivers/gpu/drm/drm_sysfs.c                   |  7 ++
>  drivers/gpu/drm/exynos/exynos_hdmi.c          | 11 ++-
>  drivers/gpu/drm/imx/imx-ldb.c                 | 13 ++-
>  drivers/gpu/drm/imx/imx-tve.c                 |  8 +-
>  drivers/gpu/drm/mediatek/mtk_hdmi.c           |  9 +-
>  drivers/gpu/drm/mgag200/mgag200_mode.c        |  1 +
>  drivers/gpu/drm/msm/hdmi/hdmi_connector.c     |  1 +
>  drivers/gpu/drm/radeon/radeon_connectors.c    | 82 ++++++++++++++-----
>  drivers/gpu/drm/rockchip/inno_hdmi.c          | 17 ++--
>  drivers/gpu/drm/rockchip/rk3066_hdmi.c        | 17 ++--
>  drivers/gpu/drm/sti/sti_hdmi.c                |  1 +
>  drivers/gpu/drm/sun4i/sun4i_hdmi.h            |  1 -
>  drivers/gpu/drm/sun4i/sun4i_hdmi_enc.c        | 14 ++--
>  drivers/gpu/drm/tegra/drm.h                   |  1 -
>  drivers/gpu/drm/tegra/output.c                | 12 +--
>  drivers/gpu/drm/tegra/sor.c                   |  6 +-
>  drivers/gpu/drm/tilcdc/tilcdc_tfp410.c        |  1 +
>  drivers/gpu/drm/vc4/vc4_hdmi.c                | 16 ++--
>  drivers/gpu/drm/zte/zx_hdmi.c                 | 25 ++----
>  drivers/gpu/drm/zte/zx_vga.c                  | 25 ++----
>  include/drm/drm_connector.h                   | 11 +++
>  26 files changed, 252 insertions(+), 176 deletions(-)
> 
> -- 
> 2.17.1
> 

-- 
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch