#31 BLOC Trial-2: OHM Power Manager for OLPC laptops

[Jim Gettys]

X itself will take care of dealing with the dcon.

All Ohm has to do is ensure the right screen saver parameters get set.
                          - Jim


On Wed, 2007-07-11 at 14:55 +0000, Zarro Boogs per Child wrote:
> #31: OHM Power Manager for OLPC laptops
> -----------------------------+----------------------------------------------
>   Reporter:  jg              |       Owner:  hughsient at gmail.com
>       Type:  task            |      Status:  new                
>   Priority:  blocker         |   Milestone:  Trial-2            
>  Component:  infrastructure  |     Version:                     
> Resolution:                  |    Keywords:  power              
>   Verified:  0               |  
> -----------------------------+----------------------------------------------
> Comment (by cjb):
> 
>  Hi Richard,
> 
>  Replying to [comment:23 hughsient at gmail.com]:
>  > >  * power button support -- we should suspend whenever the power button
>  is pressed
>  >
>  > I'll do this today. I guess it's exposed in HAL as a button of type
>  power.
> 
>  (See below about us probably needing a kernel change here.)
> 
>  > >  * lid event -- we should suspend *and* set the dcon to "sleep" mode
>  via sysfs on lid close
>  >
>  > How to set dcon to sleep and suspend? What's the _exact_ commands on a
>  B3?
> 
>  DCON sleep is:
>  {{{
>  echo 1 > /sys/devices/platform/dcon # sleep
>  echo 0 > /sys/devices/platform/dcon # wake
>  }}}
> 
>  And, CPU suspend is the usual:
>  {{{
>  echo mem > /sys/power/state
>  }}}
> 
>  > >  * ebook event -- we should `xrandr -o left` on ebook=1, `xrandr -o
>  normal` on ebook=0
>  >
>  > What is the ebook event - a HAL button press or dbus api?
> 
>  Lid and ebook are already being broadcast by HAL as the appropriate
>  signals:  if you install the latest build and close/open lid and
>  flip/unflip into ebook, lshal --monitor gives:
> 
>  {{{
>  -bash-3.2# lshal --monitor
> 
>  Start monitoring devicelist:
>  -------------------------------------------------
>  14:56:51.815: computer_logicaldev_input_0 property button.state.value =
>  true
>  14:56:51.822: computer_logicaldev_input_0 condition ButtonPressed = lid
>  14:56:52.389: computer_logicaldev_input_0 property button.state.value =
>  false
>  14:56:52.397: computer_logicaldev_input_0 condition ButtonPressed = lid
>  14:56:56.328: computer_logicaldev_input_1 property button.state.value =
>  true
>  14:56:56.429: computer_logicaldev_input_1 condition ButtonPressed =
>  tablet_mode
>  14:56:57.370: computer_logicaldev_input_1 property button.state.value =
>  false
>  14:56:57.377: computer_logicaldev_input_1 condition ButtonPressed =
>  tablet_mode
>  }}}
> 
>  > Can we do the xranr stuff in c bindings rather than run a command - it
>  would be much faster.
> 
>  That sounds fine, though I don't have sample code for doing it with the
>  bindings, and would be happy with getting the exec going now and
>  optimizing it later given our time constraints.  Whichever you prefer.
> 
>  > > HAL doesn't currently see/broadcast the power button -- maybe that's
>  because X uses the grab ioctl on the pm_inputdev device, which would mean
>  we need to split out the power button into its own (correctly labeled)
>  device like we did with lid and ebook.  That's a simple kernel patch; if
>  we need to do that, I can get it done quickly.
>  >
>  > Yup, it needs to be a separate device, ala ACPI.
> 
>  Yeah, makes sense.  I'll get a kernel RPM with the extra device for the
>  lid switch ready for when you get in tomorrow.
> 
>  > I'll make this stuff priority one this morning.
> 
>  You rock.  :)  Thanks so much!
> 
-- 
Jim Gettys
One Laptop Per Child