battery_fuel_gauge: Make the default battery type customizable

Currently the default battery type is a constant.

There is a need that a board can support both 2S and 3S batteries,
according to its SKU ID. For example, a SKU which uses 2S battery
will use a 2-to-1 switching capacitor to regulate the output
voltage. A SKU which uses 3S battery will use a 3-to-1 switching
capacitor.

If the battery is not attached, the default battery is selected to
configure the charger. A wrong battery configuration may be
selected. For example, the charger may output a 2S voltage but the
switching capacitor uses the 3-to-1 ratio.

This change enables the board to customize the default battery
type. It helps fixing the above issue.

BRANCH=Trogdor
BUG=b:175625362
TEST=Build the Lazor image and use it on the board with 3S battery
but the battery is not attached.

Signed-off-by: Wai-Hong Tam <waihong@google.com>
Change-Id: I76bf50c7226c4ec9f633d4b7f6025dc9ab464b49
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/ec/+/2597801
Reviewed-by: Diana Z <dzigterman@chromium.org>

2 files changed, 13 insertions, 1 deletions

diff --git a/common/battery_fuel_gauge.c b/common/battery_fuel_gauge.c
index 444144dfeb..4a989a0db4 100644
--- a/common/battery_fuel_gauge.c
+++ b/common/battery_fuel_gauge.c
@@ -64,6 +64,11 @@ static int get_battery_type(void)
 	return battery_type;
 }
 
+__overridable int board_get_default_battery_type(void)
+{
+	return DEFAULT_BATTERY_TYPE;
+}
+
 /*
  * Initialize the battery type for the board.
  *
@@ -82,7 +87,7 @@ static inline const struct board_batt_params *get_batt_params(void)
 	int type = get_battery_type();
 
 	return &board_battery_info[type == BATTERY_TYPE_COUNT ?
-		DEFAULT_BATTERY_TYPE : type];
+		board_get_default_battery_type() : type];
 }
 
 const struct battery_info *battery_get_info(void)
diff --git a/include/battery_fuel_gauge.h b/include/battery_fuel_gauge.h
index 8b1b7106bd..36da40b274 100644
--- a/include/battery_fuel_gauge.h
+++ b/include/battery_fuel_gauge.h
@@ -71,6 +71,13 @@ int battery_bq4050_imbalance_mv(void);
 #endif
 
 /**
+ * Return the board-specific default battery type.
+ *
+ * @return a value of `enum battery_type`.
+ */
+__override_proto int board_get_default_battery_type(void);
+
+/**
  * Return 1 if CFET is disabled, 0 if enabled. -1 if an error was encountered.
  * If the CFET mask is not defined, it will return 0.
  */