[PATCH v3 0/3] Add additional YUV420 bus format check for dw-meson's bridge enable

Adrián Larumbe adrian.larumbe at collabora.com
Sun Jun 25 07:17:14 PDT 2023


This is a belated follow-up on
https://lore.kernel.org/dri-devel/20220515204412.2733803-1-adrian.larumbe@collabora.com

Commit e67f6037ae1be34b2b68 ("drm/meson: split out encoder from meson_dw_hdmi")
broke 4K display modes for me, and I discovered it was because the right
pixel clock wasn't being chosen in dw_hdmi_phy_init. I misinterpreted the
reason as a problem in figuring out whether we want to enforce YUV420 mode,
but it turned out to be a mismatch between what dw-meson code is doing and
the way the bus format is being picked by the dw-hdmi bus output format drm
helper.

I fixed it by bringing back dw-hdmi bus format check in dw-meson.

The second patch makes sure YUV420 bus format is the only one being
returned by dw-hdmi's output format bridge function when that's the only
drm mode allowed.

Changelog:

v3:
        - Change commit message for all three commits to accurately
        reflect the modified files' subsystem.
        - Add v1's Acked-by tags from subsystem maintainer
v2:
        - Add commit message to patch number 3 in the series

Adrián Larumbe (3):
  drm/bridge: dw-hdmi: change YUV420 selection logic at clock setup
  drm/bridge: dw-hdmi: truly enforce 420-only formats when drm mode
    demands it
  drm/bridge: dw-hdmi: remove dead code and fix indentation

 drivers/gpu/drm/bridge/synopsys/dw-hdmi.c | 35 +++++++++--------------
 drivers/gpu/drm/meson/meson_dw_hdmi.c     |  4 +--
 include/drm/bridge/dw_hdmi.h              |  2 ++
 3 files changed, 18 insertions(+), 23 deletions(-)

-- 
2.40.0




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