On Wed, 30 Mar 2016, Rafael J. Wysocki wrote:

On Tuesday, March 29, 2016 11:56:45 PM Pavel Machek wrote:

quoted

On Tue 2016-03-29 23:46:23, Rafael J. Wysocki wrote:

quoted

On Tuesday, March 29, 2016 04:24:05 PM Pavel Machek wrote:

quoted

On Tue 2016-03-29 15:06:36, Rafael J. Wysocki wrote:

quoted

On Monday, March 28, 2016 11:20:12 PM Pavel Machek wrote:

quoted

Hi!

Few releases ago, I could wake up PC from S3 sleep by hitting any
key. That ceased to work some time before, keyboard would just light a
NUM lock LED when I hit a key (4.5). Now PC seems to be sleeping (in
S3) with NUM lock LED on (4.6-rc0).

Any idea what is going on there? Does it happen for you, too? What is
the expected behaviour?

Debian 8.3, with MATE desktop, I just hit the "moon" key to make it
sleep. Keyboard is on USB.

That's rather important.

Clearly, something in the USB HID land has changed lately.

The expected behavior depends on whether or not the keyboard itself and the
USB controller are both enabled to wake up.  If they are, I'd expect any
key press to generate a wakeup event.

Is there anything in /sys I should check?

Generally, power/wakeup files under the involved devices (ie. if they are
present and what's in them if so).

/sys/class/input43 and 44 (corresponding to USB keyboard) has no such
files.

pavel@amd:/sys/devices/pci0000:00$ lsusb
Bus 001 Device 008: ID 046d:c05a Logitech, Inc. M90/M100 Optical Mouse
Bus 001 Device 064: ID 04f2:0111 Chicony Electronics Co., Ltd KU-9908
Keyboard
Bus 001 Device 005: ID 1a40:0101 Terminus Technology Inc. 4-Port HUB
Bus 001 Device 006: ID 0557:2008 ATEN International Co., Ltd UC-232A
Serial Port [pl2303]
Bus 001 Device 004: ID 058f:6254 Alcor Micro Corp. USB Hub
Bus 001 Device 071: ID 1004:618e LG Electronics, Inc. Ally/Optimus
One/Vortex (debug mode)
Bus 001 Device 002: ID 058f:6362 Alcor Micro Corp. Flash Card
Reader/Writer
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 005 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 004 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 003 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 002 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub

There are rather a lot of wakeup files here:

pavel@amd:/sys/devices/pci0000:00$ find . -name "wakeup"
./0000:00:01.0/power/wakeup
./0000:00:1b.0/power/wakeup
./0000:00:1c.0/power/wakeup
./0000:00:1c.1/power/wakeup
./0000:00:1c.1/0000:03:00.0/power/wakeup
./0000:00:1d.0/usb2/power/wakeup
./0000:00:1d.0/power/wakeup
./0000:00:1d.1/usb3/power/wakeup
./0000:00:1d.1/power/wakeup
./0000:00:1d.2/usb4/power/wakeup
./0000:00:1d.2/power/wakeup
./0000:00:1d.3/usb5/power/wakeup
./0000:00:1d.3/power/wakeup
./0000:00:1d.7/usb1/1-5/power/wakeup
./0000:00:1d.7/usb1/1-6/1-6.2/power/wakeup
./0000:00:1d.7/usb1/1-6/power/wakeup
./0000:00:1d.7/usb1/1-7/1-7.1/power/wakeup
./0000:00:1d.7/usb1/1-7/1-7.2/power/wakeup
./0000:00:1d.7/usb1/1-7/power/wakeup
./0000:00:1d.7/usb1/power/wakeup
./0000:00:1d.7/power/wakeup
./0000:00:1e.0/power/wakeup
./0000:00:1f.2/power/wakeup
pavel@amd:/sys/devices/pci0000:00$

root@amd:/sys/devices/pci0000:00# for a in `find . -name "wakeup"`; do
echo $a `cat $a`; done
./0000:00:01.0/power/wakeup disabled
./0000:00:1b.0/power/wakeup disabled
./0000:00:1c.0/power/wakeup disabled
./0000:00:1c.1/power/wakeup disabled
./0000:00:1c.1/0000:03:00.0/power/wakeup enabled
./0000:00:1d.0/usb2/power/wakeup disabled
./0000:00:1d.0/power/wakeup enabled
./0000:00:1d.1/usb3/power/wakeup disabled
./0000:00:1d.1/power/wakeup enabled
./0000:00:1d.2/usb4/power/wakeup disabled
./0000:00:1d.2/power/wakeup enabled
./0000:00:1d.3/usb5/power/wakeup disabled
./0000:00:1d.3/power/wakeup enabled
./0000:00:1d.7/usb1/1-5/power/wakeup disabled
./0000:00:1d.7/usb1/1-6/1-6.2/power/wakeup disabled
./0000:00:1d.7/usb1/1-6/power/wakeup disabled
./0000:00:1d.7/usb1/1-7/1-7.1/power/wakeup enabled
./0000:00:1d.7/usb1/1-7/1-7.2/power/wakeup disabled
./0000:00:1d.7/usb1/1-7/power/wakeup disabled
./0000:00:1d.7/usb1/power/wakeup disabled
./0000:00:1d.7/power/wakeup enabled
./0000:00:1e.0/power/wakeup disabled
./0000:00:1f.2/power/wakeup disabled
root@amd:/sys/devices/pci0000:00#

And the defaults are interesting, to say. But with:

for a in `find . -name "wakeup"`; do echo enabled > $a; done

It seems to wake up when I hit a key. So next question is... what
should be the default behaviour?

That's rather hard to answer.

Ideally, "enabled", but then some of those things generate spurious wakeup
events and the owners of these prefer "disabled".

Unforunately, lsusb does not print out the port number information
needed to match its output against the sysfs files.  (Not to mention
that the lsusb output shows 7 non-root-hub devices on bus 1 but the
sysfs listing shows only 6!)  I'd guess that the keyboard is
0000:00:1d.7/usb1/1-7/1-7.1/ because it's the only entry with wakeup
enabled.  What do 0000:00:1d.7/usb1/1-7/1-7.1/{product,vendor} contain?

If so, the missing ingredient may be that you need to enable
0000:00:1d.7/usb1/1-7/power/wakeup, because that's the keyboard's
parent hub.  The USB spec says that hubs are required always to relay
wakeup requests from their children to their parents, but not all hubs
do this.

The disadvantage of enabling wakeup on a hub is that it will then 
generate a wakeup request whenever a device is plugged in or unplugged.  
That's why hubs default to disabled.

On the other hand, if this used to work okay then it's unlikely that
the hub is at fault.  It's more likely that something has changed in
PCI or ACPI, so that the wakeup signal from 0000:00:1d.7 isn't sending
the computer back to S0.  But that doesn't explain why writing
"enabled" to all the power/wakeup files would make things start
working again.

Alan Stern