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

[Zarro Boogs per Child]

#31: OHM Power Manager for OLPC laptops
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  Reporter:  jg              |       Owner:  hughsient at gmail.com
      Type:  task            |      Status:  new                
  Priority:  blocker         |   Milestone:  Trial-2            
 Component:  infrastructure  |     Version:                     
Resolution:                  |    Keywords:  power              
  Verified:  0               |  
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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!

-- 
Ticket URL: <http://dev.laptop.org/ticket/31#comment:24>
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