power: pm8921-charger: enable external charger
The pmic 8921 charger has a limit of 2Amp of charge current. This limit
makes it inadequate to charge multi-cell batteries.
The pm8921 charger supports a configuration where an external charger
with more current capacity may be used to charge the battery while the
pm8921 itself can charge from a USB source. In such a configuration
the external charger source is connected to the DCIN pins, this makes the
pmic detect insertion and removal of the external charger source. In turn
this enables automatic switching on or off the usb charging path when an
external charger is plugged out or in respectively. The pm8921 charger
driver has to call start and stop on external charger. The internal
FSM and logic correctly indicates that it is charging from a DC source.
The resume charging of a fully charged battery when an external source
is present needs to start charging from an external source. The driver
relies on VBATDET comparator to signal a low.
Change-Id: Iab5439ac2408ab061bce477f4d41d7b6a8de9b38
Signed-off-by: Amir Samuelov <amirs@codeaurora.org>
2 files changed