Motorola Droid 4 progress, power consumption
Pavel Machek
pavel at ucw.cz
Wed May 2 12:10:49 PDT 2018
Hi!
> > Anyway, >5.5hours of standby with screen off, GSM on is already
> > usable.
>
> Just to rub that in, you do mean GSM usable for voice calls and
> SMS with your unicsy_demo with mainline kernel plus the pending
> LCD related patches, right? :)
Plus some other patches, yes.
> > This is the core of code I'm using.
> >
> > https://github.com/pavelmachek/unicsy_demo
> >
> > Battery graphs are attached. I'm not sure if the battery was really
> > close to empty at that point -- voltage curve should have different
> > shape if that was the case.
>
> Cool. BTW, the value for POWER_SUPPLY_POWER_AVG should be quite
> accurate for the whole device power consumption.
Aha, I was looking in the wrong directory. Yes, these look useful.
> It comes from the shunt resistor measured by the PMIC. Sorry I don't
> remember how often it needs to be polled but I'm guessing polling it
> once a minute or so should be plenty.
Ok. I normally do once in 30 seconds.
> Hmm oh and the POWER_SUPPLY_CHARGE_COUNTER value should be monitored
> by your libbattery and it's low value and high value should be saved
> to a file. Low should be saved when we get the battery low interrupt
> and battery state changes to POWER_SUPPLY_CAPACITY_LEVEL_CRITICAL.
> High value should be saved on POWER_SUPPLY_CAPACITY_LEVEL_FULL.
>
> Then when you know the high value and low value, you can calculate
> the remaining capacity based on the current value and
> POWER_SUPPLY_POWER_AVG.
Ok, more stuff on TODO list. I actually use python hacks, and not
libbattery now.
Is this one correct?
voltage_min_design:3100000
I believe you mentioned flash stops working at 3.3V. What is important
from my point of view is to shut the system down when the battery is
low. I believe that still needs to be implemented.
Is it appropriate to shutdown at POWER_SUPPLY_CAPACITY_LEVEL_CRITICAL?
But then libbattery will race with shutdown to save the thresholds...
I also have some hacks to allow configuration of the full
voltage. Charging to 4.35V is pretty agressive, and I believe baterry
will be damaged less if we only charge to 4.1V.
Best regards,
Pavel
--
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html
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