Tx2-4g r32.3.1 dtc error

getting Warning (reg_format): “reg” property in /i2c1/gpio@77 has invalid length (4 bytes) (#address-cells == 2, #size-cells == 1)

what does it mean and why does it show up on some i2c devices and not all.

We moved an gpio expansion from i2c0 to i2c8 on a custom board and the 0x77 is not showing up, and the gpio expansion is not being added to the system.

i2cdetect does not see the 0x77 until we do a i2cget on it and then i2cdetect sees the 0x77, but that is not useful because we need it to be added at boottime so we can use the gpio expansion.


hello terrysu50z,

could you please attach full warning messages from kernel side for reference,

These warning are seen during the dtc of the device tree, there are no messages from the kernel side.

Solution: was using i2c8 instead of i2c@xxxxxxxx in my device tree, which caused the Warnings, after changing to the long name the warnings went away and my expansion gpio was detected. It appears the i2c* in the device tree should not be used when adding to the device tree, only the long names. Remember i2cdectect -l is your friend that gives you the good xxxxxxxx addresses for changing device tree.