Enable I2C fast mode under Linux on Colibri iMX7

Technical Support
, , ,
1

Hello,

I use the Linux Image V2.6.1 on a Colibri iMX7 SoM and have a 9-DOF motion sensor connected to the I2C bus (/dev/i2c-3). At the moment I am not able to read much more than 64,000 bits per second from the sensor. I assume the I2C bus is running in standard mode at 100 kbit/s. My questions are: 1) How can I detect the speed the I2C bus is actually running at? 2) How can I switch the I2C bus into fast mode (400 kbits/s)?

Thanks for any helpful advice,
Jens

2

I2C bus speed is set in the device tree. See the imx7-colibri device tree file here. One can change the clock-frequency to 400000, compile the device tree and then update the same on the module. Also see the following article.

3

Thanks for the help. Now I can read 96,000 bits per second from the sensor via I2C without problems.