#2765 BLOC Update.: Need programmable delay to turn off DCON chip. (was: EC needs programmable delay to turn off DCON chip.)

[Zarro Boogs per Child]

#2765: Need programmable delay to turn off DCON chip.
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  Reporter:  jg                   |       Owner:  rsmith  
      Type:  defect               |      Status:  new     
  Priority:  blocker              |   Milestone:  Update.1
 Component:  power manager (OHM)  |     Version:          
Resolution:                       |    Keywords:  power   
  Verified:  0                    |  
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Changes (by jg):

 * cc: dilinger (added)
  * component:  embedded controller => power manager (OHM)


Old description:

> While the DCON can power down the LCD on its own after a programmable
> delay (already being used by the DPMS code in the X server, I believe),
> the DCON itself consumes lots of power (several hundred
> millwatts).  We need to get it off when not in use.
>
> Rather than waking up the system (in ebook mode, in particular) just to
> turn off the DCON, I'd like to be able to set a timeout to turn off the
> DCON as well, complimentary to the DCON's control of the LCD panel.

New description:

 While the DCON can power down the LCD on its own after a programmable
 delay (already being used by the DPMS code in the X server, I believe),
 the DCON itself consumes lots of power (several hundred
 millwatts).  We need to get it off when not in use after a second delay.
 I'm concerned about a child reading a book and forgetting
 to get the screen completely off.

 We need to be able to set a timeout to turn off the DCON as well,
 complimentary to the DCON's control of the LCD panel.

--

Comment:

 not even clear it should be in the kernel... It may be something we do in
 ohm, by waking up completely...

 let's see where the OHM path leads, before we presume we have to hack the
 kernel or EC...

-- 
Ticket URL: <https://dev.laptop.org/ticket/2765#comment:8>
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