lkml.org 
[lkml]   [2015]   [Jun]   [29]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
SubjectRe: [PATCH][RFC] usbhid: enable autosuspend for internal devices
From
Date
On Sat, 2015-06-27 at 08:29 +0200, Jiri Kosina wrote:
> On Fri, 26 Jun 2015, Greg Kroah-Hartman wrote:

> Last time we were testing this, autosuspend for USB HID devices was quite
> a disaster.
>
> Do you have any idea whether udev developers tested the "autosuspend on by
> default for USB HID devices" on reasonable set of devices?
>
> The culrpits that I remember from top of my head (it's been long time
> ago):
>
> - the LEDs for suspended device go off. This is very confusing at least on
> keyboards, and brings really bad user experience

That is a bug. hidinput_count_leds() is supposed to prevent that.
What did you test?

> - many keyboards were losing first keystroke when waking up from suspend.
> We've been debugging this with Alan, and never root-caused it to a
> problem in our code, it seems to be the property of the HW

- mice don't wake up from movement alone.

And again I would state that we don't get enough information
from user space. Hardware seems to be designed for sleeping
while a screen saver is on. In kernel space we just get a binary
input desired or not desired from open/close.
That is insufficient.

Regards
Oliver





\
 
 \ /
  Last update: 2015-06-29 12:01    [W:1.017 / U:0.692 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site