[Nexus 7 (2013) General] CTCaer:
Our touchscreen has also a rough calibrate as they are calling it. I don't know if it runs timely by the firmware.

But you can force it with "echo ff > /proc/ektf_dbg"

If done correctly, in the kernel msg log you will find

[ektf3k]:[elan] dump cmd: 54, 29, 00, 01

[ektf3k]:Run command: 0x000000FF result:0

EDIT:

Also you can check your fw version by "cat /sys/devices/i2c-3/3-0010/vendor"

Modified fw will show a version bigger than _A044 to disable flashing of newer one.

Actually Nexus 7 2013 probably doesn't have different touchscreen revisions. Well, anyway, drivers and fw can't distinguish them for sure.

The different firmwares are obtainable by the kernel source. They are basically bugfixing versions. Like let's say android 4.4.1 to 4.4.2.

The problem in our tablets arise firstly from the totally crap ESD (electostatic discharge) protection mechanisms and the huge EMIs (Electromagnetic interference) produced by mainly our LCD's WLED back light driver and also other power components.

You can learn more if you search for touchscreen ESD protection and EMI.

So in most cases in these forums (hovering, ghost touches, unintentional releases, etc ), the problem comes from EMI produced by the things I said above.

So when the interference is strong, when we touch the screen it starts behaving very bad.

Why only when you touch it though? Our devices, have a problem in noise radiating from our fingers. So our body catches the radiated noise from the backlight driver (mainly), fluorescent lamps, charger, or whatever is lower than 1MHz and transmits it to the touchscreen.

This is way problematic because this is the frequency range that touchpanels work. But ours have a crap algorithm and shielding that can't cope with it.

What you can do? 2 things as many said before:

Minimize EMI by covering and protecting touscreen components and EMI radiating power components inside the tablet.

Trying different firmware versions.

Let's see option 2:

All and I mean ALL touchscreen manufacturers have ESD protection algorithms in software/firmware.

Some/Most have also hardware design and mechanisms/shields for ESD protection.

So for all this noise that I said before, the solution is by using frequency hopping and heavy algorithms that identify and eliminate this ghost touches.

So if you checked the fw versions, you will see that they tried/fixed/introduced such mechanisms. Let's check some and take a guess on why:

Improve "under table lamp" performance. //Probably because of EMI from the electronic transformer of a Halogen table lamp

Modify Open/Short Calibration Mechanism for ESD problem //And others for calibration ESD mechanisms, fix for timely(?) calibrations to identify EMI

Fix the Sensitivity Problem That Suspend and Wake up When Charging //They have different protections for EMI based on power source and drainage, like battery, AC charger and slimport hdmi (huge EMI coming from TV).

Noise problem. // That's clear

Add ESD Protection Mechanism //Aha

And well many others that are disguised but are problems coming from EMI noise.

As you see, they try and try and try(some fw have the same bug issue 2 times, that means a fail in previous fix) but the problem is there.

Why? Elan tech has the worst touchscreens and also ASUS was stupid not to check the behavior between the LCD and ELAN tech touchscreen. Ask people with laptops that have ELANtech touchpads. I don't know any of them, that they don't disabled it completely and use a mouse.

So why these firmwares have different results to different nexus 7 2013s?

Because of different algorithms and different calibrations. Also the devices have differences in build (humans assembly them) so different EMI patterns. It seems that A011 (if this is what sfhub calls as a ts-10) has the most heavy heuristic algorithm and the biggest SNR.

So yeah if you have (sporadic) problems that don't fall in extreme cases (non-sporadic or long occurrence), a specific fw may fix it for you.