Disconnect USB device (or disable USB) before shut down/power off
I'm completely new to Ubuntu/Linux, but after using XP (workstation), Vista (business notebook) and Mac OS X (private notebook) I thought it would be nice to have a media center PC with Ubuntu/XBMC
So I bought a Antec Case with integrated Soundgraph iMON LCD/IR device, an nVidia ION 330 mb, a harddrive and some memory and started to install Ubuntu 9.04 Desktop with XBMC-standalone.
After I spend the weekend with the terminal window, my big three problems (alsa, lirc, lcdproc) a solved - except one issue:
The Soundgraph LCD is connected directly to the computers power supply (to turn it on via IR, i think) which means the backlight is also on when the computer is turned off.
When you use the iMON Software under Windows, the software will switch off the backlight before windows is shutting down. It stays off until you power on the computer again.
So I tried the same with the LCD server... you have the option to turn the backlight off when LCDd is not running - and this works. So if I use "/etc/init.d/lcdd stop" the backlight switches off. The same will happen when you shut down the computer - BUT: approx. 1 second before the computer is powering down, the backlight will be switched on. I figured out that this will not occur when I unplug the USB cable after the backlight has been switched off - and it will not turn on again if I plug it in again (until I start the computer - which is good!)
I think it could be a possible solution to disconnect the USB LCD device in ubuntu right after the LCDd has been killed by /etc/init.d/lcdd stop command. Or, if this does not work, to disable the USB (ports) completly when shutting down (and enabling it again when booting).
If this would be possible it could be easily added to the stop script (I think...). Any suggestions?
And in addition (or as a workaround):
Is it possible to stop LCDd for suspend/hibernation? (As the LCD will have the backlight on in this modes - because LCDd is not stopped)
Of course LCDd has then to be started again when the computer is powered on.
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