[v2] drm/display: hdmi: provide common code to get Audio Clock Recovery params

[PATCH v2 0/3] drm/display: hdmi: provide common code to get Audio Clock Recovery params

Posted by Dmitry Baryshkov 8 months, 2 weeks ago

HDMI standards define a recommended set of values to be used for Audio
Clock Regeneration. Nevertheless, each HDMI driver dealing with audio
implements its own way to determine those values. Implement a common
helper and use it for MSM HDMI (tested), VC4 and DW-HDMI (compile-tested
only) drivers.

Note, this helper simply implements the database for these values (HDMI
Section 7.2). The question of selecting supported formats and rates
should be handled by sound/soc/codecs/hdmi-codec.c (pretty much like it
is handled by sound/pci/hda/patch_hdmi.c).

Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>
---
Changes in v2:
- Added missing EXPORT_SYMBOL(drm_hdmi_acr_get_n_cts) (LKP)
- Extended documentation to explicitly mention L-PCM (Maxime)
- Dropped VC4 and rockchip patchets as I'm not able to test them.
- Link to v1: https://lore.kernel.org/r/20250309-drm-hdmi-acr-v1-0-bb9c242f4d4b@linaro.org

---
Dmitry Baryshkov (3):
      drm/display: hdmi: provide central data authority for ACR params
      drm/msm/hdmi: move msm_hdmi_audio_update() out of msm_hdmi_set_timings()
      drm/msm/hdmi: use new helper for ACR tables

 drivers/gpu/drm/display/drm_hdmi_helper.c | 168 ++++++++++++++++++++++++++++++
 drivers/gpu/drm/msm/hdmi/hdmi_audio.c     | 107 ++-----------------
 drivers/gpu/drm/msm/hdmi/hdmi_bridge.c    |   8 +-
 include/drm/display/drm_hdmi_helper.h     |   6 ++
 4 files changed, 186 insertions(+), 103 deletions(-)
---
base-commit: 2bdde620f7f2bff2ff1cb7dc166859eaa0c78a7c
change-id: 20250308-drm-hdmi-acr-7ad1f0d012df

Best regards,
-- 
Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>

Re: [PATCH v2 0/3] drm/display: hdmi: provide common code to get Audio Clock Recovery params

Posted by Dmitry Baryshkov 7 months, 2 weeks ago

On Tue, 08 Apr 2025 16:54:24 +0300, Dmitry Baryshkov wrote:
> HDMI standards define a recommended set of values to be used for Audio
> Clock Regeneration. Nevertheless, each HDMI driver dealing with audio
> implements its own way to determine those values. Implement a common
> helper and use it for MSM HDMI (tested), VC4 and DW-HDMI (compile-tested
> only) drivers.
> 
> Note, this helper simply implements the database for these values (HDMI
> Section 7.2). The question of selecting supported formats and rates
> should be handled by sound/soc/codecs/hdmi-codec.c (pretty much like it
> is handled by sound/pci/hda/patch_hdmi.c).
> 
> [...]

Applied, thanks!

[2/3] drm/msm/hdmi: move msm_hdmi_audio_update() out of msm_hdmi_set_timings()
      https://gitlab.freedesktop.org/lumag/msm/-/commit/1735917ac44a
[3/3] drm/msm/hdmi: use new helper for ACR tables
      https://gitlab.freedesktop.org/lumag/msm/-/commit/88321e3529f1

Best regards,
-- 
Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>

Re: (subset) [PATCH v2 0/3] drm/display: hdmi: provide common code to get Audio Clock Recovery params

Posted by Dmitry Baryshkov 8 months, 1 week ago

On Tue, 08 Apr 2025 16:54:24 +0300, Dmitry Baryshkov wrote:
> HDMI standards define a recommended set of values to be used for Audio
> Clock Regeneration. Nevertheless, each HDMI driver dealing with audio
> implements its own way to determine those values. Implement a common
> helper and use it for MSM HDMI (tested), VC4 and DW-HDMI (compile-tested
> only) drivers.
> 
> Note, this helper simply implements the database for these values (HDMI
> Section 7.2). The question of selecting supported formats and rates
> should be handled by sound/soc/codecs/hdmi-codec.c (pretty much like it
> is handled by sound/pci/hda/patch_hdmi.c).
> 
> [...]

Applied to drm-misc-next, thanks!

[1/3] drm/display: hdmi: provide central data authority for ACR params
      commit: fec450ca15af63649e219060f37a8ec673333726

Best regards,
-- 
With best wishes
Dmitry