]> git.ipfire.org Git - thirdparty/linux.git/commit
drm/display: hdmi: provide central data authority for ACR params
authorDmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>
Tue, 8 Apr 2025 13:54:25 +0000 (16:54 +0300)
committerDmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>
Tue, 15 Apr 2025 11:05:14 +0000 (14:05 +0300)
commitfec450ca15af63649e219060f37a8ec673333726
treef9d5988e63671cdf3b58833d3d054cfdb20b4cb9
parentf8cc87024d1a1261f71dd2413951b87875b3422f
drm/display: hdmi: provide central data authority for ACR params

HDMI standard defines recommended N and CTS values for Audio Clock
Regeneration. Currently each driver implements those, frequently in
somewhat unique way. Provide a generic helper for getting those values
to be used by the HDMI drivers.

The helper is added to drm_hdmi_helper.c rather than drm_hdmi_audio.c
since HDMI drivers can be using this helper function even without
switching to DRM HDMI Audio helpers.

Note: currently this only handles the values per HDMI 1.4b Section 7.2
and HDMI 2.0 Section 9.2.1. Later the table can be expanded to
accommodate for Deep Color TMDS char rates per HDMI 1.4 Appendix D
and/or HDMI 2.0 / 2.1 Appendix C).

Reviewed-by: Maxime Ripard <mripard@kernel.org>
Link: https://lore.kernel.org/r/20250408-drm-hdmi-acr-v2-1-dee7298ab1af@oss.qualcomm.com
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>
drivers/gpu/drm/display/drm_hdmi_helper.c
include/drm/display/drm_hdmi_helper.h