# Kernel cannot detect touchpad

## eugen_mihailescu

Hi,

I am using a Compaq 6820s laptop which comes with a touchpad.

The problem is that the kernel does not detect the touchpad.

The kernel is configured as following:

 *Quote:*   

> CONFIG_INPUT_MOUSEDEV=y
> 
> CONFIG_INPUT_MOUSEDEV_PSAUX=y
> 
> CONFIG_INPUT_EVDEV=y
> ...

 

I am using Gentoo with kernel version: Linux 3.0.6-gentoo SMP x86_64 Intel(R) Core(TM)2 Duo CPU T7250 @ 2.00GHz GenuineIntel GNU/Linux

I should also add that my /etc/make.conf has the following input devices:

 *Quote:*   

> INPUT_DEVICES="keyboard mouse evdev synaptics"

 

I have also the following driver installed:

 *Quote:*   

> x11-drivers/xf86-input-synaptics 1.4.0

 

Is does not matter how is my Xorg configured while kernel cannot detect that touchpad.

The command below:

grep "N: Name=" /proc/bus/input/devices

shows anything else but not the touchpad:

 *Quote:*   

> N: Name="Sleep Button"
> 
> N: Name="Lid Switch"
> 
> N: Name="Power Button"
> ...

 

My /dev/input shows the folowing devices:

 *Quote:*   

> event0
> 
> event1
> 
> event2
> ...

 

I can confirm that mice and mouse0 are pointers to my external USB mouse (I just tested with cat /dev/input/{mouse0,mice}).

Note also that /dev/input/event{0,1,2,3,4} does not responds to mouse events.

I have 

 *Quote:*   

> dmesg|grep -i synap

 

but without results.

I have no ideea what else to check or how to make it works.

Does anyone else had problem with touchpad and found a working solution?

----------

## Telemin

Hi Eugen,

Odds are that since it not being picked by the kernel and getting a device node that you have a USB touchpad but not the kernel drivers for it.

You can confirm by running lsusb, (emerge sys-apps/usbutils) and seeing if it is listed/

Check that you have selected usb HID support in your kernel config.

```

Device Drivers

     ---> HID Devices

         [*] USB Human Interface Device (full HID) support

```

I think this is what I had to do with my recent laptop (although it is currently on loan to a family member so I can't confirm)

-Telemin-

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## eugen_mihailescu

 *Telemin wrote:*   

> Odds are that since it not being picked by the kernel and getting a device node that you have a USB touchpad but not the kernel drivers for it.
> 
> You can confirm by running lsusb, (emerge sys-apps/usbutils) and seeing if it is listed/
> 
> 

 

You said that I have a USB touchpad.  I hope neigher I haven't said that or it could be understand from my post, because I don't have a USB touchpad.

More than that, the "Logitech USB-PS/2 Optical Mouse" shown in the previous post is a physical USB mouse (that I am forced to use it because my touchpad is not recognized by kernel).

Anyway, I have checked the lsusb and how I expected only the USB attached devices were shown (such as external HDD, Logitech external USB mouse, root hubs).

 *Telemin wrote:*   

> 
> 
> Check that you have selected usb HID support in your kernel config.
> 
> ```
> ...

 

I have checked this in the kernel configuration, the "USB Human Interface Device (full HID) support" is/was set so it is included in kernel.

Thanks for your suggestions, I am open to any suggestion because I don't know what to do more than I have already done or checked.

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## roarinelk

post a full dmesg please.  Every touchpad I've come across at least starts up in

a PS/2 compatibility mode which the kernel does have a driver for.

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## eugen_mihailescu

 *roarinelk wrote:*   

> post a full dmesg please.  Every touchpad I've come across at least starts up in
> 
> a PS/2 compatibility mode which the kernel does have a driver for.

 

Hi, thanks for follow-up. My dmesg shows like:

 *Quote:*   

> e calculated using timer frequency.. 3989.91 BogoMIPS (lpj=1994958)
> 
> pid_max: default: 32768 minimum: 301
> 
> Mount-cache hash table entries: 256
> ...

 

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## roarinelk

The PS/2 controller is there, but nothing is detected.  Are you sure it is enabled?  On laptops

the touchpad can be en/disabled via hotkey (and in the BIOS as well).

Also, please remove CONFIG_INPUT_MOUSEDEV from your .config. It's a relic for

compatibility with the old X "input-mouse" driver, which has been superseded by evdev.

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## eugen_mihailescu

 *roarinelk wrote:*   

> The PS/2 controller is there, but nothing is detected.  Are you sure it is enabled?  On laptops
> 
> the touchpad can be en/disabled via hotkey (and in the BIOS as well).

 

It must be enabled because I have no BIOS/hotkey option to do it.

 *roarinelk wrote:*   

> 
> 
> Also, please remove CONFIG_INPUT_MOUSEDEV from your .config. It's a relic for
> 
> compatibility with the old X "input-mouse" driver, which has been superseded by evdev.

 

Thanks for this info. I've changed it, I will recompile the kernel right away.

About my touchpad: I will try to boot a Ubuntu LiveCD and see if my touchpad will be recognized (few months ago I can remember that it works on Ubuntu).

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## MetalGod

I have the same issue but i guess its a kernel problem since on 3.2 works. Gentoo-sources have an Ubuntu patch for alps but it doesnt work for me

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## eugen_mihailescu

 *MetalGod wrote:*   

> I have the same issue but i guess its a kernel problem since on 3.2 works. Gentoo-sources have an Ubuntu patch for alps but it doesnt work for me

 

This is a useful piece of information. I am using kernel 3.0.6 so maybe I have to wait little bit, if there is no other solution at all...

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## roarinelk

 *MetalGod wrote:*   

> I have the same issue but i guess its a kernel problem since on 3.2 works. Gentoo-sources have an Ubuntu patch for alps but it doesnt work for me

 

I have one of these new touchpads; current -git kernel recognizes it as a generic PS/2 mouse.  With input-next applied,

it gets recognized as an ALPS pad.  The point is, if it works it is at least detected as a simple 2-button mouse.

If the kernel doesn't even see that, then it must be disabled (by hardware/bios/acpi).

One thing for the OP to try ist to boot with "acpi=off" and check if it appears then?

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## MetalGod

using git-sources (3.2) my elantech touchpad (samsung laptop) gets recognized as a touchpad and it's confirmed by gnome-control-center 3.2.

Only 3.1.x is giving me problems. I'm not sure if the 3.1.x gentoo-sources that includes the Ubuntu alps patch is broken but at least it doesn't work on my laptop.

I suggest to try 3.0.x or 3.2-rcX. On my laptop fedora 16 (after updates) and ubuntu 11.10 detected the touchpad so it must be something wrong i've been doing.

See https://bbs.archlinux.org/viewtopic.php?id=107581

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## MetalGod

 *MetalGod wrote:*   

> using git-sources (3.2) my elantech touchpad (samsung laptop) gets recognized as a touchpad and it's confirmed by gnome-control-center 3.2.
> 
> Only 3.1.x is giving me problems. I'm not sure if the 3.1.x gentoo-sources that includes the Ubuntu alps patch is broken but at least it doesn't work on my laptop.
> 
> I suggest to try 3.0.x or 3.2-rcX. On my laptop fedora 16 (after updates) and ubuntu 11.10 detected the touchpad so it must be something wrong i've been doing.
> ...

 

funny thing with git-sources 3.2-rc5 works perfectly but after starting gnome 3.2 the mouse stops working. Testing the touchpad with fluxbox or gdm login works ok.

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