[PATCH 0/2] dts: Add CEC clock to DW HDMI

Jernej Skrabec jernej.skrabec at gmail.com
Fri Nov 19 23:34:46 PST 2021


Experimentation proved that CEC controller in H3-like DW-HDMI core
depends on 32 kHz clock output from RTC. If board has external 32768 Hz
crystal, HDMI CEC always work. However, if external crystal is missing
and 32 kHz clock is generated by internal oscillator, CEC communication
may or may not work, depending on accuracy. Changing internal oscillator
prescaler can make CEC work.

This was totally missed when implementing HDMI support, because user
manual has no CEC information besides the fact that it exists.

Please take a look.

Best regards,
Jernej

Jernej Skrabec (2):
  arm64: dts: allwinner: a64: Add CEC clock to HDMI
  ARM: dts: sunxi: Add CEC clock to DW-HDMI

 arch/arm/boot/dts/sun8i-r40.dtsi              | 4 ++--
 arch/arm/boot/dts/sunxi-h3-h5.dtsi            | 4 ++--
 arch/arm64/boot/dts/allwinner/sun50i-a64.dtsi | 4 ++--
 3 files changed, 6 insertions(+), 6 deletions(-)

-- 
2.34.0




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