[Trac #1433] Backlight can't be turned down well enough

[Zarro Boogs per Child]

#1433: Backlight can't be turned down well enough
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 Reporter:  gnu     |        Owner:  blizzard 
     Type:  defect  |       Status:  new      
 Priority:  normal  |    Milestone:  Untriaged
Component:  distro  |   Resolution:           
 Keywords:          |  
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Comment (by gnu):

 With further experimentation, I was able to turn down the backlight by
 using a text console and echoing values to /sys/class/backlight/dcon-
 bl/brightness.

 However, that was a very non-deterministic process.  The actual_brightness
 value would vary
 widely from the one that I had set.  The lowest one set by the keyboard
 keys had an actual_brightness of 5.  Setting brightness to 1 did enable a
 lower brightness Sugar interface, which was still usable in the dark.

 But setting it to 4 and then to 1 produced an actual brightness of zero,
 and indeed no light.  There's some odd nonlinearity, or dependency on
 previous values, that shouldn't be there in the kernel interface.  Setting
 brightness to 1 should always set it to 1 (duh).

-- 
Ticket URL: <http://dev.laptop.org/ticket/1433#comment:1>
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