question

Kevin Windrem avatar image
Kevin Windrem asked

Bug report: Brightness maximum being set incorrectly on Raspberry PI

/Settings/Gui/Brightness is being set to a max of 100 when Venus OS boots.

The maximum value of the Raspberry PI 7" touchscreen is 255 so the maximum brightness available is about 40%.

You can set the brightness to a higher value in the Display menu but it is set back to 100 after boot. dbus-spy will only allow values up to 100 as well.

Restarting the gui (killall gui) resets the max to 100.

Venus OSRaspberry Pi
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jeroen avatar image jeroen ♦ commented ·

Hello @Kevin Windrem, can you check what /sys/class/backlight/backlight/max_brightness contains for this backlight driver.

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Kevin Windrem avatar image Kevin Windrem jeroen ♦ commented ·
It's 255.

FYI, this value propagates to the veplatform values used in the Display menu. So I think the issue is just the /Settings value that's reset each time the GUI boots.

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jeroen avatar image jeroen ♦ Kevin Windrem commented ·

Ah indeed, the backlight has a max of 100 at the moment. That shouldn't be hard to fix.


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1 Answer
Kevin Windrem avatar image
Kevin Windrem answered ·

My RpiDisplaySetup now resets the max brightness value every time the GUI starts up. This is a messy way to solve the problem but it appears to work.

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