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I have a phone attached to my laptop using an USB so that it shares the internet connection over the wire without using Wi-Fi hotspot (it draws a lot of power). But it draws a lot of power from the laptop battery by an undesired charging.
I'd like to find out a way to let the kernel tell the USB chip to restrict the amperage towards the connected device so that the phone doesn't draw any power at all, but solely communicate the internet connection.
I've read the docs about USB power management, but unfortunately found nothing I can use.
Is it even possible? If not, than what is the catch?