Customizing suspend/resume on Apalis iMX6

Hello,

I am working with the Apalis iMX6Q running TorizonCore. I have been experimenting with the low power modes, and have run into problems with the suspend state.

When I put the module into standby, I am able to bring it back out in its original state using MXM3 pin 37, as described in this tutorial:
https://developer.toradex.com/knowledge-base/suspend-resume-(linux)

However, I would like to use the suspend mode to reduce power consumption further. When I put the module into the suspend state, I am able to bring it out again by driving pin 37 low, but when I do this the module does not seem to restart all of the peripherals that were originally running: the ethernet port does not get re-enabled, and the shell does not re-appear on the LCD screen I have attached.

It also seems possible that the peripherals do power back up but all the processes the CPU had been running never get re-launched, because the power consumption after wakeup is considerably larger than the power consumption prior to entering the suspend mode.

Does anybody have any insight into what is going on here? Is there a way that I can customize which peripherals get powered on/off when suspending and resuming? How are these processes configured? If this is not a power on/off issue and the problem is with Linux, is systemd responsible for restarting processes after exiting suspend mode?

Thanks,

Josh

Greetings @jtrebuchon,

I can confirm that I was able to reproduce this issue on my end. After some digging I believe this is related to this known issue: https://developer.toradex.com/software/linux/linux-software/release-details?view=all&key=ELB-2169

Torizon builds on top of our normal BSP so this seems to be an inherited issue in Torizon. Also the issue currently marks Colibri i.MX6 as the only SoM affected but I believe this is an error on our part.

I believe currently the issue fell into our backlog, but I can check with the team on the status and maybe renewed efforts if possible.

Best Regards,
Jeremias

Hello @jeremias.tx,

I see. For now I can just stick to using standby mode. Thanks for your help!

-Josh

Thanks for your Input. Please check the page above to know when this feature will be implemented.

Best regards,
Jaski