[LightDM] No Keyboard Touchpad with lightdm Mate / Dell Latitude E6420

[Edouard Guigné]

Hello,

I installed last week a Dell laptop E6420 in centos 7 with Mate desktop.
Installation looked good, I used a remote connexion through ssh and xrdp 
session to configure the laptop ( I installed first "X Window system" 
then "MATE Desktop" and switch to graphical.target)
When I finished it, I wanted to login locally on the laptop ; but I 
faced a strange issue : I cannot use the inputs keyboard and touchpad...
I tried to plug a external usb keyboard and mouse : same issue, cannot 
input.

I noticed that the problem seems to be with lightdm service.
Because when I stop the service # systemctl stop lightdm and I can logon 
through tty with using the laptop keyboard.

With the lightdm logon screen, the keyboard and touchpad are not working...

I am not used to configure keyboard/mouse on linux. Usually It was 
working good on all my centos 7 or fedora xx installations with Mate 
Desktop.
First time I get this issue.

Physically, everything seems to be good :
# cat /proc/bus/input/devices
I: Bus=0019 Vendor=0000 Product=0005 Version=0000
N: Name="Lid Switch"
P: Phys=PNP0C0D/button/input0
S: Sysfs=/devices/LNXSYSTM:00/device:00/PNP0C0D:00/input/input0
U: Uniq=
H: Handlers=event0
B: PROP=0
B: EV=21
B: SW=1

I: Bus=0019 Vendor=0000 Product=0001 Version=0000
N: Name="Power Button"
P: Phys=PNP0C0C/button/input0
S: Sysfs=/devices/LNXSYSTM:00/device:00/PNP0C0C:00/input/input1
U: Uniq=
H: Handlers=kbd event1
B: PROP=0
B: EV=3
B: KEY=10000000000000 0

I: Bus=0019 Vendor=0000 Product=0003 Version=0000
N: Name="Sleep Button"
P: Phys=PNP0C0E/button/input0
S: Sysfs=/devices/LNXSYSTM:00/device:00/PNP0C0E:00/input/input2
U: Uniq=
H: Handlers=kbd event2
B: PROP=0
B: EV=3
B: KEY=4000 0 0

I: Bus=0019 Vendor=0000 Product=0001 Version=0000
N: Name="Power Button"
P: Phys=LNXPWRBN/button/input0
S: Sysfs=/devices/LNXSYSTM:00/LNXPWRBN:00/input/input3
U: Uniq=
H: Handlers=kbd event3
B: PROP=0
B: EV=3
B: KEY=10000000000000 0

I: Bus=0011 Vendor=0001 Product=0001 Version=ab41
N: Name="AT Translated Set 2 keyboard"
P: Phys=isa0060/serio0/input0
S: Sysfs=/devices/platform/i8042/serio0/input/input4
U: Uniq=
H: Handlers=sysrq kbd event4
B: PROP=0
B: EV=120013
B: KEY=1100f02902000 8380307cf910f001 feffffdfffefffff fffffffffffffffe
B: MSC=10
B: LED=7

I: Bus=0019 Vendor=0000 Product=0006 Version=0000
N: Name="Video Bus"
P: Phys=LNXVIDEO/video/input0
S: 
Sysfs=/devices/LNXSYSTM:00/device:00/PNP0A08:00/device:13/LNXVIDEO:00/input/input5
U: Uniq=
H: Handlers=kbd event5
B: PROP=0
B: EV=3
B: KEY=3e000b00000000 0 0 0

I: Bus=0003 Vendor=045e Product=00cb Version=0111
N: Name="Microsoft Microsoft Basic Optical Mouse v2.0 "
P: Phys=usb-0000:00:1d.0-1.2/input0
S: 
Sysfs=/devices/pci0000:00/0000:00:1d.0/usb2/2-1/2-1.2/2-1.2:1.0/input/input6
U: Uniq=
H: Handlers=mouse0 event6
B: PROP=0
B: EV=17
B: KEY=70000 0 0 0 0
B: REL=103
B: MSC=10

I: Bus=0011 Vendor=0002 Product=0008 Version=0000
N: Name="DualPoint Stick"
P: Phys=isa0060/serio1/input1
S: Sysfs=/devices/platform/i8042/serio1/input/input7
U: Uniq=
H: Handlers=mouse1 event7
B: PROP=21
B: EV=7
B: KEY=70000 0 0 0 0
B: REL=3

I: Bus=0011 Vendor=0002 Product=0008 Version=0300
N: Name="AlpsPS/2 ALPS DualPoint TouchPad"
P: Phys=isa0060/serio1/input0
S: Sysfs=/devices/platform/i8042/serio1/input/input8
U: Uniq=
H: Handlers=mouse2 event8
B: PROP=9
B: EV=b
B: KEY=e420 70000 0 0 0 0
B: ABS=260800001000003

I: Bus=0010 Vendor=001f Product=0001 Version=0100
N: Name="PC Speaker"
P: Phys=isa0061/input0
S: Sysfs=/devices/platform/pcspkr/input/input9
U: Uniq=
H: Handlers=kbd event9
B: PROP=0
B: EV=40001
B: SND=6

I: Bus=0019 Vendor=0000 Product=0000 Version=0000
N: Name="Dell WMI hotkeys"
P: Phys=wmi/input0
S: Sysfs=/devices/virtual/input/input10
U: Uniq=
H: Handlers=kbd event10
B: PROP=0
B: EV=13
B: KEY=1000b00000400 0 e000000000000 0
B: MSC=10

I: Bus=0000 Vendor=0000 Product=0000 Version=0000
N: Name="HDA Intel PCH Dock Mic"
P: Phys=ALSA
S: Sysfs=/devices/pci0000:00/0000:00:1b.0/sound/card0/input11
U: Uniq=
H: Handlers=event11
B: PROP=0
B: EV=21
B: SW=10

I: Bus=0000 Vendor=0000 Product=0000 Version=0000
N: Name="HDA Intel PCH Mic"
P: Phys=ALSA
S: Sysfs=/devices/pci0000:00/0000:00:1b.0/sound/card0/input12
U: Uniq=
H: Handlers=event12
B: PROP=0
B: EV=21
B: SW=10

I: Bus=0000 Vendor=0000 Product=0000 Version=0000
N: Name="HDA Intel PCH Dock Line Out"
P: Phys=ALSA
S: Sysfs=/devices/pci0000:00/0000:00:1b.0/sound/card0/input13
U: Uniq=
H: Handlers=event13
B: PROP=0
B: EV=21
B: SW=40

I: Bus=0000 Vendor=0000 Product=0000 Version=0000
N: Name="HDA Intel PCH Headphone"
P: Phys=ALSA
S: Sysfs=/devices/pci0000:00/0000:00:1b.0/sound/card0/input14
U: Uniq=
H: Handlers=event14
B: PROP=0
B: EV=21
B: SW=4

I: Bus=0000 Vendor=0000 Product=0000 Version=0000
N: Name="HDA NVidia HDMI/DP,pcm=3"
P: Phys=ALSA
S: Sysfs=/devices/pci0000:00/0000:00:01.0/0000:01:00.1/sound/card1/input15
U: Uniq=
H: Handlers=event15
B: PROP=0
B: EV=21
B: SW=140

I: Bus=0000 Vendor=0000 Product=0000 Version=0000
N: Name="HDA NVidia HDMI/DP,pcm=7"
P: Phys=ALSA
S: Sysfs=/devices/pci0000:00/0000:00:01.0/0000:01:00.1/sound/card1/input16
U: Uniq=
H: Handlers=event16
B: PROP=0
B: EV=21
B: SW=140

I: Bus=0000 Vendor=0000 Product=0000 Version=0000
N: Name="HDA NVidia HDMI/DP,pcm=8"
P: Phys=ALSA
S: Sysfs=/devices/pci0000:00/0000:00:01.0/0000:01:00.1/sound/card1/input17
U: Uniq=
H: Handlers=event17
B: PROP=0
B: EV=21
B: SW=140

Thank for your help.

-- 
Edouard Guigné
LMS - Ecole Polytechnique
PALAISEAU
01.69.33.57.77