fwk: implement the battery extender feature

The purpose of this function is to automatically drop the battery max
charge voltage if the system is left plugged in to AC for a long time
to preserve battery life.

When the timer is exceeded the battery charge voltage should be reduced
to 4.35V/cell. Two additional days after the timer has exceeded, the
battery charge voltage shall be reduced to 4.3V/cell.

The timer should reset to 0 days any time the system is in S0/S0ix and
not attached to AC for 30 minutes or longer.

BRANCH=marigold
BUG=https://app.clickup.com/t/86eq06zen
TEST=when timer expired, the charge voltage will reduce to 97% and
96% battery maximum charge voltage
TEST=charge voltage will recover when the user unplugs the adapter
for 30 minutes when the system in S0/S0ix.

Signed-off-by: Josh-Tsai <[email protected]>

Author: Josh-Tsai

common/charge_state.c

@@ -479,6 +479,12 @@ int charge_request(bool use_curr, bool is_full)
 #endif
 	}
 
+#ifdef CONFIG_CUSTOMIZED_DESIGN
+	/* Override the voltage if the battery extender is on */
+	if (battery_extender_stage_voltage(battery_get_info()->voltage_max))
+		voltage = battery_extender_stage_voltage(battery_get_info()->voltage_max);
+#endif
+
 	if (curr.ac) {
 		if (prev_volt != voltage || prev_curr != current)
 			CPRINTS("%s(%dmV, %dmA)", __func__, voltage, current);
@@ -1640,6 +1646,15 @@ void charger_task(void *u)
 
 		prev_full = is_full;
 
+#ifdef CONFIG_CUSTOMIZED_DESIGN
+		/**
+		 * Run the battery extender function to check the timer,
+		 * if the timer expired, will override the voltage in the
+		 * charge_request() function.
+		 */
+		battery_extender();
+#endif
+
 		adjust_requested_vi(info, is_full);
 
 		process_preferred_voltage();

include/charge_state.h

@@ -433,6 +433,19 @@ int board_want_charger_change_mode(void);
 #include "charge_state.h"
 
 #ifdef CONFIG_CUSTOMIZED_DESIGN
+/**
+ * Callback for boards to return voltage value.
+ *
+ * @param voltage	battery maximum voltage
+ * @return battery extender stage voltage (stage1: 97% * voltage; stage2: 96% * voltage).
+ */
+int battery_extender_stage_voltage(uint16_t voltage);
+
+/**
+ * Callback for boards to count the battery extender timer.
+ */
+void battery_extender(void);
+
 void battery_customize(struct charge_state_data *curr_batt);
 #endif
 

zephyr/program/framework/CMakeLists.txt

@@ -23,6 +23,9 @@ zephyr_library_sources_ifdef(CONFIG_PLATFORM_EC_LED_COMMON
 zephyr_library_sources_ifdef(CONFIG_PLATFORM_EC_LED_COMMON
 	"src/led.c")
 
+zephyr_library_sources_ifdef(CONFIG_PLATFORM_EC_CHARGE_MANAGER
+	"src/battery_extender.c")
+
 if(DEFINED CONFIG_BOARD_LOTUS)
 	project(lotus)
 	cros_ec_library_include_directories_ifdef(CONFIG_BOARD_LOTUS include)

zephyr/program/framework/include/board_host_command.h

@@ -430,4 +430,29 @@ struct ec_response_get_cutoff_status {
 	uint8_t status;
 } __ec_align1;
 
+/*****************************************************************************/
+/*
+ * Battery extender control
+ */
+#define EC_CMD_BATTERY_EXTENDER	0x3E24
+
+struct ec_params_battery_extender {
+	uint8_t disable;
+	uint8_t days;
+	uint16_t minutes;
+	uint8_t cmd;
+	uint8_t manual;
+} __ec_align1;
+
+struct ec_response_battery_extender {
+	uint8_t current_stage;
+	uint16_t days;
+	uint16_t minutes;
+} __ec_align1;
+
+enum battery_extender_cmd {
+	BATT_EXTENDER_WRITE_CMD,
+	BATT_EXTENDER_READ_CMD,
+};
+
 #endif /* __BOARD_HOST_COMMAND_H */