Kobo framebuffer: workaround to support +4.0FW

platform/kobo/koreader.sh

@@ -114,9 +114,20 @@ fi
 # we keep maximum 500K worth of crash log
 cat crash.log 2> /dev/null | tail -c 500000 > crash.log.new
 mv -f crash.log.new crash.log
+
+# TODO: add support for 32bit framebuffer in koreader. This is a workaround
+# to run koreader in 16bpp. Useful since FW 4.0
+FB_BPP=$(cat /sys/class/graphics/fb0/bits_per_pixel)
+[ "$FB_BPP" -gt 16 ] && /usr/sbin/fbset -depth 16
+# fix rotation issues on Kobo Aura HD (dragon) and Kobo Aura H2O (dahlia)
+case "$PRODUCT" in "dragon" | "dahlia" ) cat /sys/class/graphics/fb0/rotate > /sys/class/graphics/fb0/rotate ;; esac
+
 ./reader.lua "${args}" >> crash.log 2>&1
 RESULT=$?
 
+# back to default depth in framebuffer.
+[ "$FB_BPP" -gt 16 ] && /usr/sbin/fbset -depth "$FB_BPP"
+
 if [ "${FROM_NICKEL}" = "true" ] ; then
 	if [ "${FROM_KFMON}" != "true" ] ; then
 		# start kobo software because it was running before koreader