evdevtouch: Could not read from input device (No such device)

chaithubk

I am running a Qt Application on Nitrogen board. I have connected a HDMI supported Multi Touchscreen monitor to the Nitrogen board, and my Qt application is working fine on the touchscreen.

But intermittently am noticing this error on the console

evdevtouch: Could not read from input device (No such device)

... and touch user interaction is not getting recognized at that point.
Any suggestion why this is happening ?

Thanks in advance.

SGaist

Hi,

Do you mean that your application is running fine for some time and then suddenly the input device disappears ?

chaithubk

@SGaist Yes. Some times the input device auto recovers and some times I keep noticing the above error in the console and input device is not responding.

Basically my Qt application contains a ChartView QML item which displays a simple LineSeries and I am trying to add a marker on the ChartView area - which gets displayed when user clicks any point on the graph. When I try to click on a point in the graph area and try to drag the marker I am noticing this error intermittently.

evdevtouch: Could not read from input device (No such device)
No release received for 1 touch points over QQuickMouseArea(0x106da90, parent=0x101dc08, geometry=0,0 1223x659) on touch end.

This error is not occurring all the time. Am worried if I messed up something.

SGaist

Are you disconnecting something when that message occurs ?

chaithubk

@SGaist No, am not disconnecting anything.

SGaist

Looks like there's something happening to your device rather than a problem with your application.

Avtansh Sharma

@chaithubk
Are you reading from your device

continously
or
just reading from it when device notifies you that data has arrived

In the scenario 1 device will misbehave like you have mentioned