06-02-2024, 02:03 PM
It looks like none of the Pi Touch specific settings in Peripheral Config work with Bookworm KMS video driver. There are fixes for two of the three settings.
Brightness: Add "dtoverlay=rpi-backlight" to [all] section in config.txt
Rotate screen: Add "video=DSI-1:800x480@60,rotate=180" to end of cmdline.txt
Pixel aspect: No solution. Circles will look oval, squares oblong because square pixels apparently can't be configured in the frame buffer as they could in the old Firmware mode BCM2835 video driver.
It seems every major OS bump causes a lot of configuration issues with these DSI/SPI displays. At this point it's clear that the direction in Bookworm is toward HDMI displays.
I tested the two fixes listed above and they work with the default KMS video driver. There is an option in System Config named "Integrated audio" that allows the old Firmware mode driver to be used instead of the KMS driver but this is meant specifically as a hack for a Headphone-only audio config and not for reverting to the BCM driver for displays which is absolutely not supported!
I'll plan to implement these two fixes and a fix for pixel aspect ratio if one is discovered.
Brightness: Add "dtoverlay=rpi-backlight" to [all] section in config.txt
Rotate screen: Add "video=DSI-1:800x480@60,rotate=180" to end of cmdline.txt
Pixel aspect: No solution. Circles will look oval, squares oblong because square pixels apparently can't be configured in the frame buffer as they could in the old Firmware mode BCM2835 video driver.
It seems every major OS bump causes a lot of configuration issues with these DSI/SPI displays. At this point it's clear that the direction in Bookworm is toward HDMI displays.
I tested the two fixes listed above and they work with the default KMS video driver. There is an option in System Config named "Integrated audio" that allows the old Firmware mode driver to be used instead of the KMS driver but this is meant specifically as a hack for a Headphone-only audio config and not for reverting to the BCM driver for displays which is absolutely not supported!
I'll plan to implement these two fixes and a fix for pixel aspect ratio if one is discovered.
