[Q] Center touchscreen unresponsive - Can't type

[sombody]

My nexus s at times tends to be unresponsive at the center part of the screen. This problem has actually plague me from since I was in stock 2.3.1 and followed on up to now. From my searches, I know I'm not the only one that has this problem and some speculate that having a screen protector contributes to this problem.

My best bet is that this would be more of a software problem than a hardware side as a quick lock/unlock always fixes this issue. Below is a request by someone in cyanogenmod and I find that his response seems to have some good basis. I was hoping with a better background in developing this stuff could help. Also what to know who else out there is experiencing the same problem.

Recently I've got a Nexus S, and I fount its touchscreen sometimes unresponsive, especially right after unlock. The center of the screen cannot sense tapping, but the edge and corner area works well. The four soft keys always works great, but I think they are controlled by a different cypress chip. I've tried to connect adb and "cat /dev/input/event0" and the result confirms my observation. Searching a Chinese android-lover forum, I found several guys are experiencing similar problem. (Some are running stock, others, including me runs CM-7rc). The problem can be strangely solved by locking and unlocking the phone quickly, and when the touchscreen is working correctly, it's actually very sensitive and responsive.

Suspecting a driver issue, I looked into the source of touchscreen controller (AMTEL MXT224) driver (/driver/input/mxt224.c) by Samsung and compared it to drivers of the same chip by Motorola and HTC. I notice that HTC and Moto's drivers send calibrate signals to the touchscreen controller in there resume method, but samsung's does not. I doubt whether it's the cause of issue. Modifying driver and compiling android kernel are beyond my knowledge, so I'm calling for help.
I know not all nexus s are suffering this, so I'm read to test and provide feedback. Any help would be greatly appreciated!

HTC driver (http://pastebin.com/7BZvp50x, http://pastebin.com/wxMV9ifY)


Moto driver (http://pastebin.com/5jnT8jvv, http://pastebin.com/yNH3nUa5)