Node             SN                   Model                                    
Namespace Usage                      Format           FW Rev  
---------------- -------------------- ---------------------------------------- 
--------- -------------------------- ---------------- --------
/dev/nvme0n1     182940620027         PC SN720 NVMe WDC 256GB                  
1         256.06  GB / 256.06  GB    512   B +  0 B   10101012

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https://bugs.launchpad.net/bugs/1805775

Title:
  PC SN720 NVMe WDC 256GB consumes more power in S2Idle than long idle

Status in HWE Next:
  New
Status in linux-oem package in Ubuntu:
  In Progress

Bug description:
  [Impact]
  On new systems that facilitate s2idle, we observed the power consumption 
raises higher than long idle does during s2idle with Western Digital PC SN720 
NVMe SSD SDAPNTW-256G.

  Short idle: 5.3
  Long idle: 3.0
  S2I: 5.07

  [Fix]
  Windows doesn't put nvme to D3 in modern standby, and uses its own APST 
feature to do the power management. To leverage its APST feature during s2idle, 
we can't disable nvme device while suspending, too.
  So, here is what we did on the driver, 1. prevent nvme from entering D3, 2. 
prevent nvme from being disabled when suspending.

  [Test]
  Verified on the WD NVMe, it fixes the power consumption issue with no 
regression. And the power consumption decreases to 1.66W during s2idle.

  [Regression Potential]
  Low, the patches only applied to specific nvme module, and from our test, the 
system is still stable.

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