I am unaware as to who sets clock speed on the i2c bus and specifically on the /dev/i2c-2 which is exposed on the board so as to drive external equipment.
I am looking into the linux-boundary kernel files in yocto (dylan) build dir, but I cannot figure out where that is set.
To be honest I don't even know if i'll find that info there, but it seems like the right place to start (after googling about it of course).
So who determined the speed (standard mode, fast mode, etc) for the external i2c? if it is a driver , which one should I be looking for?
The reason is I am trying to drive some TMC222 low-power stepper motor control ICs, but they do not respond.
Note I have successfully connected a number of other i2c ICs (among others the pca9505x).
An answer is not necessary. Any pointers as to how to go about it , so I can learn about this is more than welcome.
Thank you for your help.