I am using IMX7 Dual SABRE Board. I've built the Yocto project and booted through the SD card. The board has booted fine and everything is working as expected. I want to interface an I2C device with a slave address 0x60. I connected SDA, SCL, GND, and VCC (tried both 3.3V and 5V) to mikroBus pins on the IMX7Dual Evaluation board (SCH-28590 REV D1). But I am unable to communicate with the I2C slave device.
Upon analyzing using i2c-tools I found that there is a device showing up on I2C-2 address 0x60 always even when nothing is connected on the mikroBus pins.
root@imx7dsabresd:~/i2c# ./i2cdetect -y 2
0 1 2 3 4 5 6 7 8 9 a b c d e f
00: -- -- -- -- -- -- -- -- -- -- -- -- --
10: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
20: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
30: -- -- -- -- -- -- -- -- -- UU -- -- -- -- -- --
40: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
50: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
60: 60 -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
70: -- -- -- -- -- -- -- --
The I2C slave dev board I am connecting has three I2C slave chips (0x50, 0x60 and 0x64). So after connecting it to the mikroBus port I run the i2cdetect again,
root@imx7dsabresd:~/i2c# ./i2cdetect -y 2
0 1 2 3 4 5 6 7 8 9 a b c d e f
00: -- -- -- -- -- -- -- -- -- -- -- -- --
10: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
20: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
30: -- -- -- -- -- -- -- -- -- UU -- -- -- -- -- --
40: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
50: 50 -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
60: 60 -- -- -- 64 -- -- -- -- -- -- -- -- -- -- --
70: -- -- -- -- -- -- -- --
As you can see slave 0x50 and 0x64 are showing up now. 0x60 was there before connecting itself. I can talk to the slaves at 0x50 and 0x64 successfully but not able to communicate at 0x60. I tried the slave 0x60 on RPi it worked fine. So the problem is on the IMX7 side.
Upon investigation, I found MPL3115A2 (I2C precision pressure sensor) is at 0x60 on I2C-2 Bus. I tried to remove it and recompile the code as well.
#CONFIG_MPL3115=y
#CONFIG_INPUT_MPL3115=y
Just to be on the safer side I removed below lines from arch/arm/boot/dts/imx7d-sdb.dts as well.
- mpl3115@60 {- compatible = "fsl,mpl3115";- reg = <0x70>; //0x60 is used by microchip ECC608. - };
Even after recompiling the linux kernel and dts files, I am seeing the i2c device emulated
at 0x60 on I2C-2 Bus.
Can somebody please help me resolve the issue?
Are there any I2C device internally connected on the IMX7 Dual Sabre board?
