Re: [PATCH] hid: enable hid device to suspend/resume asynchronously

On Thu, 24 Sep 2015, Fu, Zhonghui wrote:

quoted

quoted

Enable hid device to suspend/resume asynchronously. This can improve
system suspend/resume speed.

How well was this tested?

Power management is notorious for not being really in excellent shape on 
many HID devices.

So I'd like to be careful.

I were on leave these days, so sorry for late reply.

This can reduce system suspend/resume time about 20ms, from 1030ms to 
1010ms on ASUS T100TA machine. Although the improvement is not very 
significant, but this can let your parent/child device suspend/resume 
more asynchronously and take advantage of multicore to improve overall 
system suspend/resume speed.

I have resent this patch with updated commit message - "[PATCH v2] hid: 
enable hid device to suspend/resume asynchronously".

Is there any reason why not enable this from userspace via sysfs instead, 
based on whitelist on known-to-be-well-behaved devices, from udev?

I am really careful when it comes to enabling features like this 
(especially given the state of PM support on some low-end devices) 
globally.

Thanks,

-- 
Jiri Kosina
SUSE Labs