Adding trickle charging mode to precharge batteries with
voltage lower than minimal design value. This CL adds
control to charger voltage to track battery input current
change.
To prevent battery from deeply discharging, this CL preserves
3% of the design capacity.
Minor bug fixes include error state check and charger control
logic.
Signed-off-by: Rong Chang <rongchang@chromium.org>
BUG=chrome-os-partner:8660,8661
TEST=manual
Plug AC power, the power adapter led should be
'yellow'. On the EC serial console, type 'battery'
and 'charger' commands.
Battery input current should staid close to its
desired current.
A deeply discharged battery (5.5V) should be revived to
a healthy state after 30 minutes ~ 4 hours.
Change-Id: Ibaa2396c6b751639d98db32f5919b1e8ec700e40
23b8885a02