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* [patch 0/2] libata: power usage patches
@ 2008-03-25 22:27 Kristen Carlson Accardi
  0 siblings, 0 replies; only message in thread
From: Kristen Carlson Accardi @ 2008-03-25 22:27 UTC (permalink / raw)
  To: jeff; +Cc: linux-ide, arjan

Hi, 
The libata core leaves the phy powered on for unoccupied ports, costing
us about .75 Watts of extra power usage.  If the port is not hotpluggable,
there's no reason to leave the port powered on if there are no devices attached
after initial probe.

As I was investigating this issue I also ran across a bug in the ahci driver -
it sets PxCMD.ST without checking to see if any devices are attached.
thanks,
Kristen

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2008-03-25 22:27 [patch 0/2] libata: power usage patches Kristen Carlson Accardi

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