Root AC plugged or USB plugged?

[thangfish]

Our Triumph can somehow recognize a plugged-in charger (not necessarily correctly) as either AC plugged or USB plugged.
I have some of each. I have a 2 amp charger that is always recognized as USB but is recognized as AC on my friends Droidx.

My question:
What is it exactly that allows our device to discriminate, assuming there is no actual computer bus involved?

Is this programmable via the kernel?

Thanks for any insight.

 

[dsmryder]

Our Triumph can somehow recognize a plugged-in charger (not necessarily correctly) as either AC plugged or USB plugged.
I have some of each. I have a 2 amp charger that is always recognized as USB but is recognized as AC on my friends Droidx.

My question:
What is it exactly that allows our device to discriminate, assuming there is no actual computer bus involved?

Is this programmable via the kernel?

Thanks for any insight.

http://www.extremetech.com/computin...ks-or-how-to-avoid-blowing-up-your-smartphone
Good article
I remember mantera talking about the kernel's involvement in the charging process. I think the charge controller is in the phone and controlled by the kernel. I hope someone could elaborate on this more.

 

[thangfish]

I hadn't read that article, but plenty like it.
They left out a specification of USB 2.0 that allows it to output up to 1 amp if requested.

Seems that most manufacturers almost completely ignore USB specs.

I still don't get why my 2a "dumb"charger shows USB plugged, even with different cables that have shown AC plugged with other dumb chargers.

Not sure yet if that means it actually charges at some lower rate or not.

 

[dsmryder]

I hadn't read that article, but plenty like it.
They left out a specification of USB 2.0 that allows it to output up to 1 amp if requested.

Seems that most manufacturers almost completely ignore USB specs.

I still don't get why my 2a "dumb"charger shows USB plugged, even with different cables that have shown AC plugged with other dumb chargers.

Not sure yet if that means it actually charges at some lower rate or not.

I think there is a series of things that need to be done to get things to work. I think one thing says it's a USB port, then the next says it's a downstream port, finally would be the dedicated charging port. If the phone doesn't recognize the port as a dedicated charging port, I think it will default to the USB spec.

Maybe if I get good at reading I'll look at the part of the kernel that relates to that

 

[thangfish]

Maybe if I get good at reading I'll look at the part of the kernel that relates to that

Ha!
Yeah, like you really need something else to study!