I am running the aml-s905x-cc (aka le potato) board on Ubuntu 22.04
Is there any documentation addressing power management ?
→ repartition of power draw by peripheral and how to shut down some peripherals (eg. USB, Sound, Video, IR, I2S …) ?
→ removing unnecessary linux modules ?
→ power impact when switching the CEC/Pin11 jumper ?
You can reference the schematics page to see what devices you can turn off through toggling GPIO controlled regulators for non-mandatory devices. Additionally, there are low power states that you can enter that uses very little power but you can’t do any processing when that happens and rely on select GPIO interrupts to wake the system.
All board systems are controlled via GPIO regulators. The kernel has the necessary framework and will power off the regulators if the devices are not used by software. This topic (power) is too complex to describe simply and you need to have embedded system knowledge. A book on embedded systems and the ability to read schematics is recommended.
My board is using 220mA at idle (100MHz CPU) with just Ethernet, no other devices attached. However if I plug an HDMI cable in then the power consumption goes DOWN to 200mA It doesn’t matter if the monitor is on/off, or what the CEC/GPIO11 jumper setting is. Remove the HDMI cable and the power consumption goes back up!