Switching Nokia N900 into portrait mode

Currently there is no xrandr software installed on the Maemo plattform. But xrandr library is there so all you need is a little bit of python to take advantage of it. This is slightly based on https://launchpad.net/python-xrandr . If your python software needs xrandr support on N900 I think that library might be handy.

Anyways this is the code I used:

from ctypes import *
import os
import sys
from pprint import pprint

xlib = cdll.LoadLibrary("libX11.so.6")
rr = cdll.LoadLibrary("libXrandr.so.2")


display = xlib.XOpenDisplay(os.getenv("DISPLAY"))
screen = xlib.XDefaultScreen(display)
root = xlib.XDefaultRootWindow(display, screen)

class XRRScreenConfiguration(Structure):
pass
gsi = rr.XRRGetScreenInfo
gsi.restype = POINTER(XRRScreenConfiguration)
config = gsi(display, root)

current_time = c_ulong()
rr.XRRTimes.restpye = c_ulong
timestamp = rr.XRRTimes(display, screen, byref(current_time))

xccr = rr.XRRConfigCurrentRate
xccr.restype = c_int
rate = xccr(config)

rotation = c_ushort()
size = rr.XRRConfigCurrentConfiguration(config, byref(rotation))


rr.XRRSetScreenConfigAndRate(display,config,root,size,int(sys.argv[1]),rate,timestamp)

So copy that into something like rotate.py and run it like this

• for portrait mode "python rotate.py 2"
• for landscape mode "python rotate.py 1"

Portrait mode support is currently lacking but it might have its uses. For example browser currently supports it quite nicely. In the end, I think my Nokia N900 will still be mostly in landscape orientation. Anyways this has been a nice learning experience about python, n900 and xrandr.

Updated daemon version

This will rotate the screen automatically

from ctypes import *
import os
import sys
import time
from math import atan2
from pprint import pprint

xlib = cdll.LoadLibrary("libX11.so.6")
rr = cdll.LoadLibrary("libXrandr.so.2")

def get_rotation():
    f = open("/sys/class/i2c-adapter/i2c-3/3-001d/coord", 'r' )
    coords = [int(w) for w in f.readline().split()]
    f.close()
    return coords

print get_rotation()

def rotate(angle):
    rr.XRRSetScreenConfigAndRate(display,config,root,size,angle,rate,timestamp)

display = xlib.XOpenDisplay(os.getenv("DISPLAY"))
screen = xlib.XDefaultScreen(display)
root = xlib.XDefaultRootWindow(display, screen)

class XRRScreenConfiguration(Structure):
   pass

gsi = rr.XRRGetScreenInfo
gsi.restype = POINTER(XRRScreenConfiguration)
config = gsi(display, root)

current_time = c_ulong()
rr.XRRTimes.restpye = c_ulong
timestamp = rr.XRRTimes(display, screen, byref(current_time))

xccr = rr.XRRConfigCurrentRate
xccr.restype = c_int
rate = xccr(config)

rotation = c_ushort()
size = rr.XRRConfigCurrentConfiguration(config, byref(rotation))

while True:
    [x,y,z] = get_rotation()
    print x,y,z
    if y < -500:
        rotate(1)
    elif y > 500:
        rotate(4)

    elif x < -500:
        rotate(2)
    elif x > 500:
        rotate(8)

    time.sleep(1)

This also has a bug that will reboot the phone in some situations. Probably related to software that will handle screen rotation also..