summaryrefslogtreecommitdiff
path: root/include/drm/display/drm_hdmi_helper.h
AgeCommit message (Collapse)Author
2025-04-15drm/display: hdmi: provide central data authority for ACR paramsDmitry Baryshkov
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>
2024-05-28drm/display: hdmi: Add HDMI compute clock helperMaxime Ripard
A lot of HDMI drivers have some variation of the formula to calculate the TMDS character rate from a mode, but few of them actually take all parameters into account. Let's create a helper to provide that rate taking all parameters into account. 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-v15-9-c5af16c3aae2@kernel.org Signed-off-by: Maxime Ripard <mripard@kernel.org>
2022-04-25drm/display: Move HDMI helpers into display-helper moduleThomas Zimmermann
Move DRM's HMDI helpers into the display/ subdirectoy and add it to DRM's display helpers. Update all affected drivers. No functional changes. The HDMI helpers were implemented in the EDID and connector code, but are actually unrelated. With the move to the display-helper library, we can remove the dependency on drm_edid.{c,h} in some driver's HDMI source files. Several of the HDMI helpers remain in EDID code because both share parts of their implementation internally. With better refractoring of the EDID code, those HDMI helpers could be moved into the display-helper library as well. v3: * fix Kconfig dependencies (Javier) v2: * reduce HDMI helpers to avoid exporting functions (Jani) * fix include statements (Jani, Javier) * update Kconfig symbols Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de> Reviewed-by: Javier Martinez Canillas <javierm@redhat.com> Link: https://patchwork.freedesktop.org/patch/msgid/20220421073108.19226-8-tzimmermann@suse.de