7" touchscreen on colibri does not work

Hello,

we have a AD7879 touchscreen attached to a Colibri iMX6ULL board. Driver atmel_mxt_ts is loaded and xinput says the device is enabled.

Does anybody has an idea what could be the problem?

Thanks in advance

Hi gringo

Which type of touchscreen are u using? Resistive or Capacitive? Which carrierBoard are u using? The driver atmel_mxt_ts is a capacitive touchscreen driver?

Hello,

As i can see AD7879 is a resistive touch screen driver. see link
How did you exactly connected the touchscreen?

Hi Jaski.tx,

it’s a capacitive touchscreen and with use it on an Aster carrier board.
Afaik atmel_mxt_ts is a capacitive touchscreen driver.

The driver which is actually loaded is an atmel_mxt_ts, which is a capacitive touch driver. I do not have a clue, why the device is identified as AD7879.

The touchscreen is connected via an i2c bus.

The AD7879 is a restive touch controller on the Colibri iMX6ULL module.

The capacitive touch controller is not enabled by default in our device tree. You need to enable the atmel_mxt_ts driver you need to adjust the device tree according to this instructions:
https://developer.toradex.com/knowledge-base/first-steps-with-capacitive-touch-display-7-inch-parallel#Embedded_Linux

I set

fdt_fixup ‘fdt addr ${fdt_addr_r} && fdt set /soc/aips-bus@02100000/i2c@021a0000/atmel_mxt_ts@4a status okay’

in the bootloader parameters, but it doesn’t seem to work.

Can you send a dmesg log? Thanks.