Add this as a value for enum_drm_connector_tv_mode, represented
by the string "Mono", to generate video with no colour encoding
or bursts. Define it to have no pedestal (since only NTSC-M calls
for a pedestal).

Change default mode creation to acommodate the new tv_mode value
which comprises both 525-line and 625-line formats.

Acked-by: Daniel Vetter <daniel@ffwll.ch>
Signed-off-by: Nick Hollinghurst <nick.hollinghurst@raspberrypi.com>
Signed-off-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
Signed-off-by: Maxime Ripard <mripard@kernel.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20240216184857.245372-2-dave.stevenson@raspberrypi.com

It looks like the documentation for the HDMI-related fields recently
added to both the drm_connector and drm_connector_state structures
trigger some warnings because of their use of anonymous structures:

  $ scripts/kernel-doc -none include/drm/drm_connector.h
  include/drm/drm_connector.h:1138: warning: Excess struct member 'broadcast_rgb' description in 'drm_connector_state'
  include/drm/drm_connector.h:1138: warning: Excess struct member 'infoframes' description in 'drm_connector_state'
  include/drm/drm_connector.h:1138: warning: Excess struct member 'avi' description in 'drm_connector_state'
  include/drm/drm_connector.h:1138: warning: Excess struct member 'hdr_drm' description in 'drm_connector_state'
  include/drm/drm_connector.h:1138: warning: Excess struct member 'spd' description in 'drm_connector_state'
  include/drm/drm_connector.h:1138: warning: Excess struct member 'vendor' description in 'drm_connector_state'
  include/drm/drm_connector.h:1138: warning: Excess struct member 'is_limited_range' description in 'drm_connector_state'
  include/drm/drm_connector.h:1138: warning: Excess struct member 'output_bpc' description in 'drm_connector_state'
  include/drm/drm_connector.h:1138: warning: Excess struct member 'output_format' description in 'drm_connector_state'
  include/drm/drm_connector.h:1138: warning: Excess struct member 'tmds_char_rate' description in 'drm_connector_state'
  include/drm/drm_connector.h:2112: warning: Excess struct member 'vendor' description in 'drm_connector'
  include/drm/drm_connector.h:2112: warning: Excess struct member 'product' description in 'drm_connector'
  include/drm/drm_connector.h:2112: warning: Excess struct member 'supported_formats' description in 'drm_connector'
  include/drm/drm_connector.h:2112: warning: Excess struct member 'infoframes' description in 'drm_connector'
  include/drm/drm_connector.h:2112: warning: Excess struct member 'lock' description in 'drm_connector'
  include/drm/drm_connector.h:2112: warning: Excess struct member 'audio' description in 'drm_connector'

Create some intermediate structures instead of anonymous ones to silence
the warnings.

Reported-by: Jani Nikula <jani.nikula@linux.intel.com>
Suggested-by: Jani Nikula <jani.nikula@linux.intel.com>
Fixes: 54cb39e2293b ("drm/connector: hdmi: Create an HDMI sub-state")
Fixes: 948f01d5e559 ("drm/connector: hdmi: Add support for output format")
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Signed-off-by: Maxime Ripard <mripard@kernel.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20240610111200.428224-1-mripard@kernel.org

Infoframes in KMS is usually handled by a bunch of low-level helpers
that require quite some boilerplate for drivers. This leads to
discrepancies with how drivers generate them, and which are actually
sent.

Now that we have everything needed to generate them in the HDMI
connector state, we can generate them in our common logic so that
drivers can simply reuse what we precomputed.

Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20240527-kms-hdmi-connector-state-v15-22-c5af16c3aae2@kernel.org
Signed-off-by: Maxime Ripard <mripard@kernel.org>

HDMI controller drivers will need to figure out the RGB range they need
to configure based on a mode and property values. Let's expose that in
the HDMI connector state so drivers can just use that value.

Reviewed-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20240527-kms-hdmi-connector-state-v15-20-c5af16c3aae2@kernel.org
Signed-off-by: Maxime Ripard <mripard@kernel.org>

The i915 driver has a property to force the RGB range of an HDMI output.
The vc4 driver then implemented the same property with the same
semantics. KWin has support for it, and a PR for mutter is also there to
support it.

Both drivers implementing the same property with the same semantics,
plus the userspace having support for it, is proof enough that it's
pretty much a de-facto standard now and we can provide helpers for it.

Let's plumb it into the newly created HDMI connector.

Reviewed-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
Acked-by: Pekka Paalanen <pekka.paalanen@collabora.com>
Reviewed-by: Sebastian Wick <sebastian.wick@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240527-kms-hdmi-connector-state-v15-18-c5af16c3aae2@kernel.org
Signed-off-by: Maxime Ripard <mripard@kernel.org>

Most of the HDMI controllers have an upper TMDS character rate limit
they can't exceed. On "embedded"-grade display controllers, it will
typically be lower than what high-grade monitors can provide these days,
so drivers will filter the TMDS character rate based on the controller
capabilities.

To make that easier to handle for drivers, let's provide an optional
hook to be implemented by drivers so they can tell the HDMI controller
helpers if a given TMDS character rate is reachable for them or not.

This will then be useful to figure out the best format and bpc count for
a given mode.

Reviewed-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20240527-kms-hdmi-connector-state-v15-13-c5af16c3aae2@kernel.org
Signed-off-by: Maxime Ripard <mripard@kernel.org>

Most HDMI drivers have some code to calculate the TMDS character rate,
usually to adjust an internal clock to match what the mode requires.

Since the TMDS character rates mostly depends on the resolution, whether
we need to repeat pixels or not, the bpc count and the format, we can
now derive it from the HDMI connector state that stores all those infos
and remove the duplication from drivers.

Reviewed-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20240527-kms-hdmi-connector-state-v15-11-c5af16c3aae2@kernel.org
Signed-off-by: Maxime Ripard <mripard@kernel.org>

Just like BPC, we'll add support for automatic selection of the output
format for HDMI connectors.

Let's add the needed defaults and fields for now.

Reviewed-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20240527-kms-hdmi-connector-state-v15-7-c5af16c3aae2@kernel.org
Signed-off-by: Maxime Ripard <mripard@kernel.org>

We'll add automatic selection of the output BPC in a following patch,
but let's add it to the HDMI connector state already.

Reviewed-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20240527-kms-hdmi-connector-state-v15-4-c5af16c3aae2@kernel.org
Signed-off-by: Maxime Ripard <mripard@kernel.org>

The next features we will need to share across drivers will need to
store some parameters for drivers to use, such as the selected output
format.

Let's create a new connector sub-state dedicated to HDMI controllers,
that will eventually store everything we need.

Reviewed-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
Reviewed-by: Sui Jingfeng <sui.jingfeng@linux.dev>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20240527-kms-hdmi-connector-state-v15-3-c5af16c3aae2@kernel.org
Signed-off-by: Maxime Ripard <mripard@kernel.org>