Reported by Nikolaus Schaller, Apr 9, 2016
The Pyra has a bq27621 fuel gauge chip. This assumes a nominal capacity by design of 2450 mAh. The Pyra battery has 6000 mAh which should be defined in the device tree node of the bq27621 chip (or a battery subnode). To fix the calculations of empty/full battery the driver http://lxr.free-electrons.com/source/drivers/power/bq27xxx_battery.c should reprogram the bq27621 chip during probing (or if it finds a mismatch of registers 0x3C and 0x3D). The procedure to update the DESIGN_CAPACITY register is described here: http://www.ti.com/lit/ug/sluuad4c/sluuad4c.pdf see section "3.1 Data Memory Parameter Update Example" on page 12. A good solution appears to be to patch http://lxr.free-electrons.com/source/drivers/power/bq27xxx_battery.c# L714 by adding a check if the design capacity matches a DT node entry and try a reprogram on mismatch.
Comment 1 by Nikolaus Schaller, Apr 9, 2016
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