Just wondering anyone have any experience with using the MPR121 Capacitive touch controller on a NanoPi Neo 2 or any other SBC? I have try the following:
Enable the i2c0 in /boot/armbianEnv.txt
Compile the mpr121 module based on guide found in:
How to Compile Just One Kernel Module
Create this dts in /boot/overlay-user
mpr121…txt (794 Bytes)
Added mpr121 in the /boot/armbianEnv.txt
and the module did load with dmesg:
[ 8.027084] mpr121_touchkey: loading out-of-tree module taints kernel.
[ 8.038693] mpr121_touchkey: module verification failed: signature and/or required key missing - tainting kernel
[ 8.040902] mpr121 0-005a: supply vdd not found, using dummy regulator
and lsmod did show mpr121 and created the device in /proc/bus/input/devices:
I: Bus=0018 Vendor=0000 Product=0000 Version=0000
N: Name=“Freescale MPR121 Touchkey”
H: Handlers=kbd event0
I ran i2cdtetect -y 0 and did show UU at address 0x5a, but when I run evtest on event0 , I got nothing.
I have checked that SDA/SCK/IRQ all have pull ups and the module is working when I tested it on a ESP32 (with pullup remove).
At this point I am a bit lost
If anyone have try this and work, help is very much appreciated.