Touchpad and mouse become insensitive on Dell Latitude-E5420 in some situation

[James Z]

Ubuntu on Dell Latitude-E5420 works not good, the touchpad and mouse sometimes will become very slow and insensitive. I have met this situation very frequently, and cause lots of time to recover it.

My environment:
Ubuntu 12.04
Laptop Dell Latitude-E5420

Problem:
Touch pad and mouse will become insensitive in some situation.

To reproduce:
1. Start computer and log in Ubuntu, plug out the external power, leave it until it come into sleep or auto shutdown (it is better to use up the battery power, but even with 40% power, it still have the issue).
2. Now plug in power and restart computer, and then you will see the problem quickly, touch pad and mouse will be very slow and insensitive.
3. Plug out external power, then touch pad and mouse works fine.
4. Plug in external power, then a short time (several seconds), the problem will happen again.

In this situation, I have to make sure there are enough battery power, and shutdown computer, restart computer then it may resolved. If there is no enough battery power then it will still have the issue.

[gagan singh (gagansingh1979)]

I am facing similar issue. My environment is similar to the filer of the bug.

Ubuntu 11.10
Dell Latitude-E5520

It was working fine and now touchpad is very unresponsive.

This happens when the power cable is plugged in. Just like the filer mentioned, the moment the power cable is removed touchpad works fine. Not sure about the first step of the filer. I always run with power connected so the battery never went down and there was no autoshutdown. But steps 3 and 4 are very much reproducible in my system as well.

Note that the touchpad works fine in windows on the same machine.

Just a guess - when power is connected to the laptop, there is a bit of static or vibration in the laptop (especially when you touch it the first time). May be some insulation is not perfect in the dell laptop. It is a new laptop. Not sure if this can affect the touchpad in ubuntu.

[Brian Moore (moore-brian-d)]

Ubuntu 12.04
Dell Latitude E5420

With touch pad
With USB optical mouse

I am having the same issue problem.

From what I'm noticing, it seems as if any mouse events become fully blocking. Everything becomes dreadfully slow, including drawing the screen.

When there is no activity with the mouse, everything works fine. Then the moment a mouse event happens, things become blocked again, until they are done being handled.

[Charleseray (charleseray)]

I'm having the same issue on my Dell Inspiron 1501 laptop.

With a fresh install of Ubuntu 12.04 I had problems with the touch pad right away. If you tried moving the cursor it would scroll horizontally a bit but not vertically and would activate the right click on the touch pad without touching it. The problem would manifest itself when the laptop would resume from hibernate.

I installed the system updates on 07/11/2012 and this problem appears to have been resolved as far as recovering from hibernate but now it happens when I plug the power cable into the laptop.