lcdproc does not shutdown imon(0038) lcd-display after system shutdown

Oh yes, version on Mythbuntu is 9.10.

BR
Sami

This is a known issue with ubuntu on many imon LCDs. In my work with lcdproc, I don't think the answer lies there. Starting and stopping the LCDd process from the command line gets the desired behavior, but something in the shutdown process appears to reset the unit, which ends up leaving the backlight on.

Related to bug #186193:
  https://bugs.launchpad.net/ubuntu/+source/linux/+bug/186193

Howdy, and thank you for helping to improve Mythbuntu by opening this ticket. After researching this quite a bit, I'm afraid that there is absolutely nothing that the Mythbuntu team can do about this problem... in fact, the expert on all things lcdproc has this problem and does not know the solution either. Leaving this ticket open would simply mislead people that the Mythbuntu team is working on a fix, when in reality, if a fix is ever found, Mythbuntu will inherit it from lcdproc, or where ever else it is fixed.

See also: http://lcdproc.sourceforge.net/docs/stable-0-5-x-user.html#imonlcd-howto
See also: mailing list thread "[Lcdproc] Onexit=1 not working Ubuntu 9.10" (copied below)

>> Jarod, you've become my source for lirc knowledge (:} )
>> ... do you know if the behaviour described below has been investigated by the lirc team? I'm nearly 100% positive that it's not a problem with lcdproc. (Well, other than the fact that lcdproc relies upon the lirc usb driver...)
>
> I've looked at it a tiny bit, as have a few other folks. My own LCD
> device has this same problem, but the backlight doesn't come back on
> until *after* the machine is powered off, so I'm not quite sure how it
> could be the driver at fault. There's a specific 'shut off the
> display' string sent to the display by the lcdproc driver, iirc, so
> when the LCDd service is stopped on my box, the display goes off, then
> the machine powers off, then the display lights back up a bit later.
> That shut-off string matches what people have snooped under windows,
> so I'm mostly clueless as to what the problem is -- some sort of reset
> of the usb bus that happens when the kernel finally exits?
>
> Sadly, I just don't have time, energy or desire to investigate this
> one more myself right now. But its definitely not an oddity of how
> Ubuntu shuts down, or at least not one specific to Ubuntu, as it
> happens the same way with the distro I run too (Fedora 12, 64-bit).
> Don't see anything at a glance in Fedora's shutdown initscripts I
> could blame.
>
>
>> ----- Original Message ----
>>> Cc: <email address hidden>
>>> Sent: Sat, February 27, 2010 11:22:59 AM
>>> Subject: Re: [Lcdproc] Onexit=1 not working Ubuntu 9.10
>>> ...
>>> > - Are you checking the "OnExit" actions by shutting down the computer
>>> > or by shutting down LCDd? ( "sudo /etc/init.d/LCDd stop" is the
>>> > easiest way to check the exit behavior)
>>> I was checking it by shutting down the computer. When I shutdown the
>>> LCDd down it seems to be working perfectly.
>>>
>>> However when shutting down the computer, it seems that the action OnExit
>>> takes place, but after a second or so the display is kind of reset. For
>>> example, when setting onexit=2 so the LCD is switch off, during the
>>> shutdown process the LCD is shutdown, but as soon as it ends the
>>> backlight is back on.
>>>
>>> I have an Antec Fusion Remote Black. Is this a normal behaviour when
>>> using this case?
>>>
>>
>> From:
>> http://lcdproc.sourceforge.net/docs/stable-0-5-x-user.html#imonlcd-howto
>>
>> "In many systems, the LCD backlight will remain on after the system is shutdow...

I didn’t know for sure if I should respond to this but it’s the only search result I could find.

I had this problem on a new build. The LCD would shut off and a few seconds later the backlight would come back on with no display.

For those that wind up here, it has nothing to do with the way Ubuntu configures it’s drivers. I spent a couple hours on this and using a multimeter discovered after the system halts the USB bus was being reset. As in, the power dropped to 0V for a second then back up to 5V. This resets the iMon display and causes the backlight to turn on with no display.

In the PC BIOS, I had enabled all wake options (from memory, Pcie, USB, lan, keyboard, mouse.)

It turns out enabling the machine to wake from a USB device causes the motherboard to reset all USB devices when the system halts so the attached USB devices can wake the system. On my motherboard, I only had to set the BIOS to wake from keyboard with any key and the iMon device will wake the system - all other options were disabled. After that, the iMon display shut off and stayed off when the system halted.

Hope this helps others.