[PATCH v2 00/13] drm: Add generic helpers for HDMI scrambling

[Daniel Vetter]

On Thu, Nov 18, 2021 at 11:38:01AM +0100, Maxime Ripard wrote:
> Hi,
> 
> This is a follow-up of the work to support the interactions between the hotplug
> and the scrambling support for vc4:
> 
> https://lore.kernel.org/dri-devel/20210507150515.257424-11-maxime@cerno.tech/
> https://lore.kernel.org/dri-devel/20211025152903.1088803-10-maxime@cerno.tech/
> 
> Ville feedback was that the same discussion happened some time ago for i915,
> and resulted in a function to do an full disable/enable cycle on reconnection
> to avoid breaking the HDMI 2.0 spec.
> 
> This series improves the current scrambling support by adding generic helpers
> for usual scrambling-related operations, and builds upon them to provide a
> generic alternative to intel_hdmi_reset_link.

Out of curiosity, can we rebuild intel_hdmi_reset_link on top of these?
Always better to have two drivers to actually show the helpers help, than
just one.
-Daniel

> 
> Let me know what you think,
> Maxime
> 
> Changes from v1:
>   - Dropped the 340MHz define
>   - Make drm_mode_hdmi_requires_scrambling use the bpc
>   - Make more drm_display_mode const in vc4
>   - Dropped the tegra conversion
>   - Added more comments
> 
> Maxime Ripard (13):
>   drm/connector: Add helper to check if a mode requires scrambling
>   drm/atomic: Add HDMI scrambler state helper
>   drm/atomic: Add HDMI reset link helper
>   drm/scdc: Document hotplug gotchas
>   drm/vc4: hdmi: Constify drm_display_mode
>   drm/vc4: hdmi: Remove unused argument in vc4_hdmi_supports_scrambling
>   drm/vc4: hdmi: Remove mutex in detect
>   drm/vc4: hdmi: Remove HDMI flag from encoder
>   drm/vc4: hdmi: Simplify the hotplug handling
>   drm/vc4: hdmi: Simplify the connector state retrieval
>   drm/vc4: hdmi: Switch to detect_ctx
>   drm/vc4: hdmi: Leverage new SCDC atomic_check
>   drm/vc4: hdmi: Reset link on hotplug
> 
>  drivers/gpu/drm/drm_atomic_helper.c       | 109 +++++++++
>  drivers/gpu/drm/drm_atomic_state_helper.c |  58 +++++
>  drivers/gpu/drm/drm_scdc_helper.c         |  13 ++
>  drivers/gpu/drm/vc4/vc4_hdmi.c            | 257 ++++++++++------------
>  drivers/gpu/drm/vc4/vc4_hdmi.h            |  19 +-
>  include/drm/drm_atomic_helper.h           |   3 +
>  include/drm/drm_atomic_state_helper.h     |   3 +
>  include/drm/drm_connector.h               |  25 +++
>  include/drm/drm_modes.h                   |  20 ++
>  9 files changed, 353 insertions(+), 154 deletions(-)
> 
> -- 
> 2.33.1
> 

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