[v4,00/23] Associate ddc adapters with connectors

Message

Andrzej Pietrasiewicz July 11, 2019, 11:26 a.m. UTC

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 next 22 patches 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.

v3..v4:

- added Reviewed-by for patch 01/23
- moved "ddc" field assignment to before drm_connector_init() is called
in msm, vc4, sti, mgag200, ast, amdgpu, radeon
- simplified the code in amdgpu and radeon at the expense of some lines
exceeding 80 characters as per Alex Deucher's suggestion
- added i915

TODO: nouveau, gma500, omapdrm, panel-simple - if applicable.
Other drivers are either already converted or don't mention neither
"ddc" nor "i2c_adapter".

Andrzej Pietrasiewicz (23):
  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
  drm/i915: Provide ddc symlink in hdmi connector sysfs directory

 .../gpu/drm/amd/amdgpu/amdgpu_connectors.c    | 56 ++++++++-----
 drivers/gpu/drm/ast/ast_mode.c                |  9 ++-
 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/i915/display/intel_hdmi.c     |  5 +-
 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        |  9 ++-
 drivers/gpu/drm/msm/hdmi/hdmi_connector.c     |  1 +
 drivers/gpu/drm/radeon/radeon_connectors.c    | 80 ++++++++++++-------
 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                | 21 ++---
 drivers/gpu/drm/zte/zx_hdmi.c                 | 25 +++---
 drivers/gpu/drm/zte/zx_vga.c                  | 25 +++---
 include/drm/drm_connector.h                   | 11 +++
 27 files changed, 240 insertions(+), 198 deletions(-)

Comments

Sam Ravnborg July 23, 2019, 9:09 a.m. UTC | #1

Hi Andrzej.

On Thu, Jul 11, 2019 at 01:26:44PM +0200, Andrzej Pietrasiewicz wrote:
> Use the ddc pointer provided by the generic connector.
> 
> Signed-off-by: Andrzej Pietrasiewicz <[e-mail]>
> ---
>  drivers/gpu/drm/ast/ast_mode.c | 9 +++++----
>  1 file changed, 5 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/gpu/drm/ast/ast_mode.c b/drivers/gpu/drm/ast/ast_mode.c
> index ffccbef962a4..1ca9bc4aa3bb 100644
> --- a/drivers/gpu/drm/ast/ast_mode.c
> +++ b/drivers/gpu/drm/ast/ast_mode.c
> @@ -890,6 +890,11 @@ static int ast_connector_init(struct drm_device *dev)
>  		return -ENOMEM;
>  
>  	connector = &ast_connector->base;
> +	ast_connector->i2c = ast_i2c_create(dev);
> +	if (!ast_connector->i2c)
> +		DRM_ERROR("failed to add ddc bus for connector\n");
> +
> +	connector->ddc = &ast_connector->i2c->adapter;
>  	drm_connector_init(dev, connector, &ast_connector_funcs, DRM_MODE_CONNECTOR_VGA);
>  
>  	drm_connector_helper_add(connector, &ast_connector_helper_funcs);
Again, assigning before drm_connector_init().
I did not audit the remaining patches - you got the idea.

	Sam