topic Imx6 touchscreen calibration in i.MX Processors

Imx6 touchscreen calibration

emmanuelperea — Fri, 04 Oct 2019 14:12:57 GMT

Hello,

I am working with a imx6 digi board, OS linux, kernel version 4.9 builded with yocto 2.4.

I need to calibrate touch screen because, when I touch near to display's border theres is a difference between the cursor and the point touched (uncalibrated).

First, I used xinput_calibrator, changing transformation matrix but i tried differents parameters configurations and I couldn't improved the function as I needed.

Then, I used tslib with ts_calibrate and when I run ts_test the touchscreen is calibrated but when I close ts_test the touchscreen is uncalibrated. It seems like the touchscreen doesn't loaded the calibration.

I have setted the following environment variables :

 export TSLIB_TSDEVICE=/dev/input/toucscreen0  export TSLIB_TSEVENTTYPE=INPUT  export TSLIB_CONFFILE=/etc/ts.conf  export TSLIB_CALIBFILE=/etc/pointercal

I believe that ts_test can read the calibration configuration parameters from pointercal file but when I close ts_test the system It cannot.

I attached two pictures, one running ts_test and another with the system running.

Someone can hellp me with this issue?

Thanks

Re: Imx6 touchscreen calibration

igorpadykov — Fri, 04 Oct 2019 23:39:45 GMT

Hi Emmanuel

one can look at boundary devices touchscreens overview which may help

https://boundarydevices.com/tag/touch-screen/

GitHub - boundarydevices/linux-imx6 at boundary-imx_4.9.x_2.0.0_ga

Best regards
igor
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Re: Imx6 touchscreen calibration

emmanuelperea — Fri, 11 Oct 2019 19:32:14 GMT

Hi Igor, thanks for response.

I take a look to the links that you shared me, and unfortunately I didn't find any help.

I will give a little more of information, maybe someone can help me.

In my linux system that I builded run matchbox-window-manager, I don't know if that maybe do a configuration o something to display.

I could run ts_test and show of same time the system coursor, so I have tslib coursor and system coursor. Tslib coursor shows in the same place that I touch the screen but system coursor It doesn't.

In this link someone had the same problem touch screen touch not working properly even after calibration using ts_calibrate - Stack Overflow

There said that maybe my destop or the app doesn't implement and use the same API that tslib offers. It recommend us ts_uinput but I had an error when I tried to use it.