Un-Initializing I2C/TWI at runtime on nrf5340 with NCS SDK 1.9.1

[sshenoy105]

Hello,

I am in the process of optimizing current consumption before we start production.. most things are where they should be. I would like to explore shutting down I2C/TWI when not needed and enable it only when needed.. I use device_get_binding and do I2C transactions and things work fine.. How do I disable/uninit the same I2C and disconnect the GPIO pins to save whatever little power I could ? is there a Zephyr API for it ? I tried looking around but couldn't find anything obvious.. I did some nrf driver APIs but wasn't sure. can you please recommend the best way to dynamically enable and disable I2C ?

Let's just say every uA counts and hence i do not want to ignore whatever little i can save.. in other words, keeping i2c enabled is not something i would like to do unless you tell me there is no other way

[sshenoy105]

hello, is there anything else I can do/add to get a response ? thank you in advance

[Øivind]

Hi, apologies for the late reply, we are always low on staff during July, so slower response times are expected.

You should be able to add CONFIG_PM_DEVICE=y to your prj.conf and then call the power management api to suspend and resume the i2c:

pm_device_action_run(i2c0, PM_DEVICE_ACTION_SUSPEND);

pm_device_action_run(i2c0, PM_DEVICE_ACTION_RESUME);

Here's some documentation on managing device power during runtime: https://developer.nordicsemi.com/nRF_Connect_SDK/doc/1.9.1/zephyr/guides/pm/device_runtime.html

[sshenoy105]

no worries.. since I didn't get any answer earlier, i had tried the PM APIs (I should have thought of them earlier) and they seem to work as expected.. thank you for confirming..