TSC2007: x, y axis changed reaction problem

JongJin Lim

Prodigy 20 points

Part Number: TSC2007

Tool/software:

Dear supporter,

My environment is,

1. Platform : embedded linux(yocto), NXP i.MX8QXP

2. Touch IC & connector : TI-TSC2007, 4wire(X+/-, Y+/-)

3. Screen resolution : 1280x1024

4. Problem :

When I touch the panel on the target board after touch calibration, the upper horizontal axis reacts when the left vertical axis is pressed, and the lower horizontal axis reacts when the right vertical axis is pressed.

I have checked several times that touch panel lines is connected correctly to the tsc2007.

I attached schematic of touch part and device tree, please let me know how I can fix it.

    	tsc2007@48 {
		compatible = "ti,tsc2007";
		gpio-controller;
		#address-cells = <1>;
		#size-cells = <0>;

		reg = <0x48>;   // 0x48 | A0~A2:00
		gpios = <&lsio_gpio1 14 1>;  // 1:active low
		pinctrl-names = "default";
		pinctrl-0 = <&pinctrl_tsc2007>;
		interrupt-parent = <&lsio_gpio1>;
		interrupts = <14 IRQ_TYPE_EDGE_FALLING>; //IMX8QXP_ADC_IN4_LSIO_GPIO1_IO14

        ti,x-plate-ohms = <100>;  
        touchscreen-size-x = <1280>;  
        touchscreen-size-y = <1024>;  
	};

5 months ago

0 Mir Jeffres 4 months ago

TI__Genius 12295 points

Hi,

Have you tried switching the connection of your X1 and Y1 to the board? Otherwise maybe you could fix it in your software solution. This seems like it would be a touch panel issue and not necessarily an issue with the chip. How are you calibrating?

Best,
Mir

0 JongJin Lim 4 months ago in reply to Mir Jeffres

Prodigy 20 points

Hi,

If I physically change x and y, it is properly recognized.

However, the same touch panel was properly recognized on other CPU (cirrus logic EP-9312) with a built-in touch driver.
So I was wondering if TSC-2007 and EP-9312 have different ways of recognizing it.

Please refer to the below image of EP-9312 touch line.

In any case, the program rotated the touch input to be recognized as the desired coordinates as follows.
But I don't know if this could cause other problems.

export QT_QPA_EVDEV_TOUCHSCREEN_PARAMETERS=rotate=270

0 Mir Jeffres 4 months ago in reply to JongJin Lim

TI__Genius 12295 points

Hi,

I think overall this should be fine, if you rotate in software and the system works, then there should not be other problems. There may be an issue with the way the TSC driver interprets the data, but it is no longer being updated so I think this should not change anytime soon.

Best,
Mir

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TSC2007: x, y axis changed reaction problem