NAK[E]/Cmnt: [SRU][PATCH][eoan] Fix additional ~5 watt power consumption after S3

[Kleber Souza]

On 24.02.20 20:23, Alex Hung wrote:
> BugLink: http://bugs.launchpad.net/bugs/1864527
> 
> [Impact]
> 
> CPU0 (and sometimes other cores too) is not entering C10 half of time
> when system is idle. "top" shows a touchpad driver takes 5%~6% of CPU
> usage, and "/proc/interrupts" reveals considerable interrupts.
> 
> [Fix]
> 
> This bug is fixed by reset touchpad during resuming.
> 
> [Test Case]
> 
> Applied the patch, suspended/resumed, and checked "top",
> "/proc/interrupts" and "powertop" 5 times to verify it worked as
> expected. Before the patch, the failure rate is 100% when not using the
> touchpad.
> 
> [Regression Risk]
> 
> Low, the patch is cherry-picked from upstream kernel. It is also
> included in bionic and focal kernels.
> 
> Kai-Heng Feng (1):
>   HID: i2c-hid: Reset ALPS touchpads on resume
> 
>  drivers/hid/i2c-hid/i2c-hid-core.c | 12 +++++++++++-
>  1 file changed, 11 insertions(+), 1 deletion(-)
> 


This fix (HID: i2c-hid: Reset ALPS touchpads on resume) has already been applied to
eoan/linux as part of Eoan upstream stable patchset:

https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1861710


Thanks,
Kleber