cjc.im / posts / Nokia N900, PostMarketOS and automatically turning off the screen

The Nokia N900[1] has to be my favorite handheld device of all time, even more so than the Nintendo Gameboy ;)

I recently discovered PostmarketOS[2], based on Alpine Linux[3] that intends to be a replacement phone OS with a 10 year lifespan. This also led me to discover that the N900 has mostly mainline Linux Kernel Support.

The one thing I wanted to happen was that the screen powers off when the keyboard slides closed. Which is done by editing /etc/acpi/handler.sh as such:

KP_SLIDE_OPEN)
    adjust_keypad_bl 255    
    echo 0 > /sys/devices/platform/omapdrm.0/graphics/fb0/blank
    ;;
KP_SLIDE_CLOSE)
    adjust_keypad_bl 0
    echo 1 > /sys/devices/platform/omapdrm.0/graphics/fb0/blank

This looks like it would also be the place to do things with the other hardware buttons on the device. More to come on this device!

[1] https://en.wikipedia.org/wiki/Nokia_N900 [2] https://www.postmarketos.org/ [3] https://alpinelinux.org/

Tags: development infosec