topic Re: Qt-embedded Touch screen problem on IMX53 (SABRE tablet) in i.MX Processors

Qt-embedded Touch screen problem on IMX53 (SABRE tablet)

winstonrodrigue — Wed, 16 Jan 2013 12:02:19 GMT

Dear All,

I have been working on a project based on QT-embedded on linux on imx53 sabre platform.

So far i have installed qt-embedded on target,
installed Qt cross compiler on host
compiled an app which runs on imx53.

But the problem is qt app does not recognize the touch.... But the touch screen driver is installed

I verified it by doing

export TSLIB_TSDEVICE=/dev/input/ts0

export TSLIB_CALIBFILE=/etc/pointercal

export TSLIB_CONFFILE=/usr/etc/ts.conf

cat /dev/innput/event2 | hexdump

When i do that and touch the screen i get the hex output..... So touch screen is detected by linux.

I have configured the qt-embedded as following.....

./configure -embedded arm -xplatform linux-mxc-g++ -release -prefix /usr/local/Trolltech/Qt-4.6.0/ -no-opengl -glib -qt-gfx-linuxfb -qt-kbd-tty -qt-kbd-linuxinput -qt-mouse-linuxinput -qt-mouse-tslib -little-endian -qt-gfx-linuxfb -host-little-endian -v -opensource -confirm-license -force-pkg-config -no-phonon

so tslib is included.

so how can i make my application get the touch input.. ??

Thanks and regards,

Winston Rodrigues,

Schiller Healthcare

Bangalore

Re: Qt-embedded Touch screen problem on IMX53 (SABRE tablet)

Yuri — Thu, 07 Feb 2013 10:52:09 GMT

The enclosed general considerations may be helpful

Re: Qt-embedded Touch screen problem on IMX53 (SABRE tablet)

LeonardoSandova — Thu, 07 Feb 2013 18:08:29 GMT

Hi Winston,

It may be the case that the GUI does not know how to interpret the touches. Can you check if the touchscreen driver can be configured/compiled to support SINGLE TOUCH?

Also, Freescale is working on YOCTO, the next BSP builder so I strongly suggest you to try it. It has QT, and the only thing you may need to do is to add a recipe with your custom application. Please take a look at his page to start using it.

i.MX Yocto FAQ

Re: Qt-embedded Touch screen problem on IMX53 (SABRE tablet)

winstonrodrigue — Tue, 12 Feb 2013 10:36:15 GMT

Dear Yuri Muhin,

I have successfully compiled tslib. and I have set the

environmental variables properly. when I run ./ts_calibrate I can see

"TSLIB calibration Utility" screen on my board. and one crosshair on

top left corner. But when i touch it Nothing happens.

I tried to do a little debugging by using printf statements in

ts_calibrate.c file just to know where exactly is the problem. It gets

struck in the function getxy();

when i see the code of getxy() in tests/testutils.c , it gets

struck at this point :

do {

printf("Inside do-getxy\n");

if (ts_read_raw(ts, &samp[0], 1) < 0) {

printf("Inside if-getxy\n");

perror("ts_read");

close_framebuffer ();

exit(1);

}

} while (samp[0].pressure == 0);

here it never comes out of the do-while loop. so i guess there is a

problem in ts_read_raw() function.

when i run ./ts_print_raw it gives me:

root@freescale /mnt/buha/bin$ ./ts_print_raw

14224.983211: 22304 24288 0

14224.987890: 22304 24288 0

14224.992615: 22304 24288 0

14224.997350: 22304 24288 0

14225.002073: 22304 24288 0

14225.006804: 22304 24288 0

14225.011538: 22304 24288 0

14225.016271: 22304 24288 0

14225.020993: 22336 24272 0

14225.042071: 22432 24272 0

14225.043366: 22432 24272 0

14226.641742: 22544 23968 0

14226.646461: 22544 23968 0

14226.651188: 22544 23968 0

14226.655925: 22544 23968 0

14226.660646: 22544 23968 0

14226.665375: 22544 23968 0

So i guess there is no problem with the touch screen driver.

It uses egalax capacitive touch screen.

Thanks and Regards,

Winston Rodrigues,

Re: Qt-embedded Touch screen problem on IMX53 (SABRE tablet)

winstonrodrigue — Tue, 12 Feb 2013 10:39:25 GMT

Dear Leonardo...

I dont know exactly how to enable single touch support...

And YOCTO is replacement for LTIB ?

Where can i download the source ?

Thanks,.,.

Winston