# [SOLVED]Kernel does not recognize touchpad

## potuz

Hi there, I have a Samsung series 5 Ultrabook, running the freshly built kernel

```
# uname -a

Linux localhost 3.8.13-gentoo #2 SMP Sat Jun 29 20:48:12 BRT 2013 x86_64 Intel(R) Core(TM) i7-3517U CPU @ 1.90GHz GenuineIntel GNU/Linux
```

My Kernel recognizes my touchpad as a generic PS/2 mouse:

```
# grep "N: Name" /proc/bus/input/devices

N: Name="Lid Switch"

N: Name="Power Button"

N: Name="Power Button"

N: Name="Video Bus"

N: Name="AT Translated Set 2 keyboard"

N: Name="PS/2 Logitech Wheel Mouse"
```

The relevant line in dmesg:

```
dmesg | grep PS/2

[    1.161854] i8042: PNP: PS/2 Controller [PNP0303:PS2K,PNP0f13:EPAD] at 0x60,0x64 irq 1,12

[    1.171176] mousedev: PS/2 mouse device common for all mice

[    1.963106] input: PS/2 Logitech Wheel Mouse as /devices/platform/i8042/serio1/input/input5
```

no matches on synaptics. The relevant part of the config is

```
# grep -i mouse /usr/src/linux/.config

CONFIG_MAC_EMUMOUSEBTN=y

CONFIG_INPUT_MOUSEDEV=y

# CONFIG_INPUT_MOUSEDEV_PSAUX is not set

CONFIG_INPUT_MOUSEDEV_SCREEN_X=1024

CONFIG_INPUT_MOUSEDEV_SCREEN_Y=768

CONFIG_INPUT_MOUSE=y

CONFIG_MOUSE_PS2=y

CONFIG_MOUSE_PS2_ALPS=y

CONFIG_MOUSE_PS2_LOGIPS2PP=y

CONFIG_MOUSE_PS2_SYNAPTICS=y

CONFIG_MOUSE_PS2_LIFEBOOK=y

CONFIG_MOUSE_PS2_TRACKPOINT=y

# CONFIG_MOUSE_PS2_ELANTECH is not set

# CONFIG_MOUSE_PS2_SENTELIC is not set

# CONFIG_MOUSE_PS2_TOUCHKIT is not set

# CONFIG_MOUSE_SERIAL is not set

# CONFIG_MOUSE_APPLETOUCH is not set

# CONFIG_MOUSE_BCM5974 is not set

# CONFIG_MOUSE_VSXXXAA is not set

# CONFIG_MOUSE_SYNAPTICS_I2C is not set

# CONFIG_MOUSE_SYNAPTICS_USB is not set

# CONFIG_USB_IDMOUSE is not set
```

And of course the settings in Xorg.conf are irrelevant since the kernel can't find the device. I can check that the device files at /dev/input/event5 (as per dmesg) responds to movement on the touchpad. So does /dev/input/mouse0.  lspci also does not show anything relevant:

```
# lspci

00:00.0 Host bridge: Intel Corporation 3rd Gen Core processor DRAM Controller (rev 09)

00:02.0 VGA compatible controller: Intel Corporation 3rd Gen Core processor Graphics Controller (rev 09)

00:14.0 USB controller: Intel Corporation 7 Series/C210 Series Chipset Family USB xHCI Host Controller (rev 04)

00:16.0 Communication controller: Intel Corporation 7 Series/C210 Series Chipset Family MEI Controller #1 (rev 04)

00:1a.0 USB controller: Intel Corporation 7 Series/C210 Series Chipset Family USB Enhanced Host Controller #2 (rev 04)

00:1b.0 Audio device: Intel Corporation 7 Series/C210 Series Chipset Family High Definition Audio Controller (rev 04)

00:1c.0 PCI bridge: Intel Corporation 7 Series/C210 Series Chipset Family PCI Express Root Port 1 (rev c4)

00:1c.3 PCI bridge: Intel Corporation 7 Series/C210 Series Chipset Family PCI Express Root Port 4 (rev c4)

00:1d.0 USB controller: Intel Corporation 7 Series/C210 Series Chipset Family USB Enhanced Host Controller #1 (rev 04)

00:1f.0 ISA bridge: Intel Corporation HM76 Express Chipset LPC Controller (rev 04)

00:1f.2 SATA controller: Intel Corporation 7 Series Chipset Family 6-port SATA Controller [AHCI mode] (rev 04)

00:1f.3 SMBus: Intel Corporation 7 Series/C210 Series Chipset Family SMBus Controller (rev 04)

01:00.0 Network controller: Intel Corporation Centrino Advanced-N 6235 (rev 24)

02:00.0 Ethernet controller: Realtek Semiconductor Co., Ltd. RTL8111/8168 PCI Express Gigabit Ethernet controller (rev 06)
```

I have seen reports on a very much quoted Arch thread https://bbs.archlinux.org/viewtopic.php?id=117109 about the same phenomenon on ALPS touchpads so my first question would be how to find out if my touchpad is an ALPS or synaptics. According to the Samsung wiki page, the pad is controlled by synaptics but it appears as "partially supported"  on a very similar machine http://wiki.gentoo.org/wiki/Samsung_Series_5_Ultra_530U3C-A02PT. In any case I'm running a newer kernel so it should be patched against the ALPS issue. Hence my second question: how do I get the kernel to recognize the touchpad? Booting with an Ubuntu live I obtain the same issue.Last edited by potuz on Wed Jul 17, 2013 7:57 pm; edited 1 time in total

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## potuz

Solved the problem, found a similar board with an elantech touchpad so the relevant line in the config was 

```
CONFIG_MOUSE_PS2_ELANTECH is not set 
```

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## kilua

Setting CONFIG_MOUSE_PS2_ELANTECH in kernel (gentoo-sources-3.8.13) .config also works for Dell's Inspiron 15R SE (7520). Thanks!

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