By default the display pixel clock needs to be evenly divide
down from the video_pll_out clock which rules out a significant
number of resolution and refresh rates.
The current clock tree looks something like:
video_pll 594000000
video_pll_bypass 594000000
video_pll_out 594000000
disp_pixel 148500000
disp_pixel_clk 148500000
Now that composite-8m supports determine_rate, we can allow
disp_pixel to set the parent rate which then switches
every clock in the chain to a new frequency when disp_pixel
cannot evenly divide from video_pll_out.
Signed-off-by: Adam Ford <aford173@gmail.com>
Reviewed-by: Fabio Estevam <festevam@gmail.com>
Signed-off-by: Abel Vesa <abel.vesa@linaro.org>
Link: https://lore.kernel.org/r/20230323230127.120883-5-aford173@gmail.com
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