brya: add control prochot feature

BUG=b:198689488
BRANCH=none
TEST=make -j BOARD=gimble

Signed-off-by: Will Tsai <will_tsai@wistron.corp-partner.google.com>
Change-Id: I4be2dc8505baffaa8b7d0c9b6949711aca370778
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/ec/+/3201831
Tested-by: Scott Chao <scott_chao@wistron.corp-partner.google.com>
Commit-Queue: Boris Mittelberg <bmbm@google.com>
Reviewed-by: Boris Mittelberg <bmbm@google.com>

3 files changed, 264 insertions, 0 deletions

diff --git a/baseboard/brya/baseboard.h b/baseboard/brya/baseboard.h
index 757b504d16..dbee995546 100644
--- a/baseboard/brya/baseboard.h
+++ b/baseboard/brya/baseboard.h
@@ -144,6 +144,16 @@
 
 #define CONFIG_PWM
 
+/* Prochot assertion/deassertion ratios*/
+#define PROCHOT_ADAPTER_WATT_RATIO 97
+#define PROCHOT_ASSERTION_BATTERY_RATIO 95
+#define PROCHOT_DEASSERTION_BATTERY_RATIO 85
+#define PROCHOT_ASSERTION_PD_RATIO 105
+#define PROCHOT_DEASSERTION_PD_BATTERY_RATIO 95
+#define PROCHOT_ASSERTION_ADAPTER_RATIO 105
+#define PROCHOT_DEASSERTION_ADAPTER_RATIO 90
+#define PROCHOT_DEASSERTION_ADAPTER_BATT_RATIO 90
+
 /* Enable I2C Support */
 #define CONFIG_I2C
 #define CONFIG_I2C_CONTROLLER
diff --git a/baseboard/brya/build.mk b/baseboard/brya/build.mk
index ca983f26ac..2ed0186242 100644
--- a/baseboard/brya/build.mk
+++ b/baseboard/brya/build.mk
@@ -10,4 +10,5 @@ baseboard-y=
 baseboard-y+=baseboard.o
 baseboard-y+=battery_presence.o
 baseboard-y+=cbi.o
+baseboard-$(HAS_TASK_PROCHOT)+=prochot.o
 baseboard-y+=usb_pd_policy.o
diff --git a/baseboard/brya/prochot.c b/baseboard/brya/prochot.c
new file mode 100644
index 0000000000..39512cf5c6
--- /dev/null
+++ b/baseboard/brya/prochot.c
@@ -0,0 +1,253 @@
+/* Copyright 2021 The Chromium OS Authors. All rights reserved.
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+#include "adc.h"
+#include "battery.h"
+#include "battery_smart.h"
+#include "charge_manager.h"
+#include "charger.h"
+#include "console.h"
+#include "driver/charger/bq25710.h"
+#include "hooks.h"
+#include "i2c.h"
+#include "math_util.h"
+#include "task.h"
+
+/* Console output macros */
+#define CPRINTS(format, args...) cprints(CC_CHARGER, format, ## args)
+
+#define ADT_RATING_W  (PD_MAX_POWER_MW / 1000)
+#define PROCHOT_EVENT_200MS_TICK    TASK_EVENT_CUSTOM_BIT(0)
+
+struct batt_para {
+	int battery_continuous_discharge_mw;
+	int battery_design_mWh;
+	int flags;
+	int state_of_charge;
+};
+
+struct batt_para batt_params;
+
+static int cal_sys_watt(void)
+{
+	int adapter_voltage_mv;
+	int IDPM;
+	int Vacpacn;
+	int V_iadpt;
+	int W_adpt;
+
+	Vacpacn = adc_read_channel(ADC_IADPT);
+
+	/* the ratio selectable through IADPT_GAIN bit. */
+	V_iadpt = Vacpacn * 1000 / 40;
+
+	IDPM = V_iadpt / CONFIG_CHARGER_SENSE_RESISTOR_AC;
+
+	adapter_voltage_mv = charge_manager_get_charger_voltage();
+
+	W_adpt = IDPM * adapter_voltage_mv / PROCHOT_ADAPTER_WATT_RATIO * 100;
+
+	return W_adpt;
+}
+
+static int get_batt_parameter(void)
+{
+	int battery_voltage;
+	int battery_current;
+	int battery_design_voltage_mv;
+	int battery_design_capacity_mAh;
+	int rv = 0;
+
+	batt_params.flags = 0;
+
+	/* read battery voltage */
+	if (sb_read(SB_VOLTAGE, &battery_voltage))
+		batt_params.flags |= BATT_FLAG_BAD_VOLTAGE;
+
+	/* Battery_current sometimes return a very huge number
+	 * and cause prochot keep toggling so add (int16_t) to guard it.
+	 */
+	if (sb_read(SB_CURRENT, &battery_current))
+		batt_params.flags |= BATT_FLAG_BAD_CURRENT;
+	else
+		battery_current = (int16_t)battery_current;
+
+	/* calculate battery wattage and convert to mW */
+	batt_params.battery_continuous_discharge_mw =
+		(battery_voltage * battery_current) / 1000;
+
+	rv |= sb_read(SB_DESIGN_VOLTAGE, &battery_design_voltage_mv);
+	rv |= sb_read(SB_DESIGN_CAPACITY, &battery_design_capacity_mAh);
+	batt_params.battery_design_mWh = (battery_design_voltage_mv *
+		battery_design_capacity_mAh) / 1000;
+
+	if (sb_read(SB_RELATIVE_STATE_OF_CHARGE, &batt_params.state_of_charge))
+		batt_params.flags |= BATT_FLAG_BAD_STATE_OF_CHARGE;
+
+	return (batt_params.flags || rv);
+}
+
+static int get_chg_watt(void)
+{
+	int adapter_current_ma;
+	int adapter_voltage_mv;
+	int adapter_wattage;
+
+	/* Get adapter wattage */
+	adapter_current_ma = charge_manager_get_charger_current();
+	adapter_voltage_mv = charge_manager_get_charger_voltage();
+	adapter_wattage = adapter_current_ma * adapter_voltage_mv / 1000 / 1000;
+
+	return adapter_wattage;
+}
+
+static int set_register_charge_option(void)
+{
+	int reg;
+	int rv;
+
+	rv = i2c_read16(I2C_PORT_CHARGER, BQ25710_SMBUS_ADDR1_FLAGS,
+		    BQ25710_REG_CHARGE_OPTION_0, &reg);
+	if (rv == EC_SUCCESS) {
+		reg |= BQ25710_CHARGE_OPTION_0_IADP_GAIN;
+		/* if AC only, disable IDPM,
+		 * because it will cause charger keep asserting PROCHOT
+		 */
+		if (!battery_hw_present())
+			reg &= ~BQ25710_CHARGE_OPTION_0_EN_IDPM;
+		else
+			reg |= BQ25710_CHARGE_OPTION_0_EN_IDPM;
+	} else {
+		CPRINTS("Failed to read bq25720");
+		return rv;
+	}
+
+	return i2c_write16(I2C_PORT_CHARGER, BQ25710_SMBUS_ADDR1_FLAGS,
+				BQ25710_REG_CHARGE_OPTION_0, reg);
+}
+
+static void assert_prochot(void)
+{
+	int adapter_wattage;
+	int adpt_mw;
+	int total_W;
+
+	/* Set 0x12 bit4=1 */
+	if (set_register_charge_option()) {
+		CPRINTS("Failed to set bq25720");
+		return;
+	}
+
+	/* Calculate actual system W */
+	adpt_mw = cal_sys_watt();
+
+	/* Read battery info
+	 * if any flag is set, skip this cycle and hope
+	 * the next cycle succeeds
+	 */
+	if (get_batt_parameter())
+		return;
+
+	/* When battery is discharging, the battery current will be negative */
+	if (batt_params.battery_continuous_discharge_mw < 0) {
+		total_W = adpt_mw +
+			ABS(batt_params.battery_continuous_discharge_mw);
+	} else {
+		/* we won't assert prochot when battery is charging. */
+		total_W = adpt_mw;
+	}
+	total_W /= 1000;
+
+	/* Get adapter wattage */
+	adapter_wattage = get_chg_watt();
+
+	/*
+	 * no AC, don't assert PROCHOT.
+	 * If AC exists, PROCHOT will only be asserted when the battery
+	 * is physical present and the battery wattage is over 95% of
+	 * the max continue discharge current of battery spec.
+	 * When the battery wattage is lower than 85% of the max
+	 * continue discharge current of battery spec, PROCHOT will be
+	 * deasserted.
+	 */
+	if (!extpower_is_present()) {
+		if (!battery_hw_present()) {
+			gpio_set_level(GPIO_EC_PROCHOT_ODL, 1);
+		} else {
+			batt_params.battery_continuous_discharge_mw =
+			ABS(batt_params.battery_continuous_discharge_mw);
+			if ((batt_params.battery_continuous_discharge_mw /
+			 1000) > BATT_MAX_CONTINUE_DISCHARGE_WATT *
+			 PROCHOT_ASSERTION_BATTERY_RATIO / 100)
+				gpio_set_level(GPIO_EC_PROCHOT_ODL, 0);
+			else if ((batt_params.battery_continuous_discharge_mw
+			 / 1000) < BATT_MAX_CONTINUE_DISCHARGE_WATT *
+			 PROCHOT_DEASSERTION_BATTERY_RATIO / 100)
+				gpio_set_level(GPIO_EC_PROCHOT_ODL, 1);
+		}
+		return;
+	}
+
+	if (adapter_wattage >= ADT_RATING_W) {
+		/* if adapter >= 60W */
+		/* if no battery or battery < 10% */
+		if (!battery_hw_present() ||
+		batt_params.state_of_charge <= 10) {
+			if (total_W > ADT_RATING_W *
+			PROCHOT_ASSERTION_PD_RATIO / 100)
+				gpio_set_level(GPIO_EC_PROCHOT_ODL, 0);
+			else if (total_W <= ADT_RATING_W)
+				gpio_set_level(GPIO_EC_PROCHOT_ODL, 1);
+		} else {
+			/* AC + battery */
+			if (total_W > (ADT_RATING_W +
+			BATT_MAX_CONTINUE_DISCHARGE_WATT))
+				gpio_set_level(GPIO_EC_PROCHOT_ODL, 0);
+			else if (total_W < (ADT_RATING_W +
+			BATT_MAX_CONTINUE_DISCHARGE_WATT) *
+			PROCHOT_DEASSERTION_PD_BATTERY_RATIO / 100)
+				gpio_set_level(GPIO_EC_PROCHOT_ODL, 1);
+		}
+	} else {
+		/* if adapter < 60W */
+		/* if no battery or battery < 10% */
+		if (!battery_hw_present() ||
+		batt_params.state_of_charge <= 10) {
+			if (total_W > (adapter_wattage *
+			PROCHOT_ASSERTION_ADAPTER_RATIO / 100))
+				gpio_set_level(GPIO_EC_PROCHOT_ODL, 0);
+			else if (total_W <= (adapter_wattage *
+			PROCHOT_DEASSERTION_ADAPTER_RATIO / 100))
+				gpio_set_level(GPIO_EC_PROCHOT_ODL, 1);
+		} else {
+			/* AC + battery */
+			if (total_W > (adapter_wattage +
+				BATT_MAX_CONTINUE_DISCHARGE_WATT))
+				gpio_set_level(GPIO_EC_PROCHOT_ODL, 0);
+			else if (total_W < (adapter_wattage +
+				(BATT_MAX_CONTINUE_DISCHARGE_WATT *
+				PROCHOT_DEASSERTION_ADAPTER_BATT_RATIO / 100)))
+				gpio_set_level(GPIO_EC_PROCHOT_ODL, 1);
+		}
+	}
+}
+
+/* Called by hook task every 200 ms */
+static void control_prochot_tick(void)
+{
+	task_set_event(TASK_ID_PROCHOT, PROCHOT_EVENT_200MS_TICK);
+}
+DECLARE_HOOK(HOOK_TICK, control_prochot_tick, HOOK_PRIO_DEFAULT);
+
+void prochot_task(void *u)
+{
+	uint32_t evt;
+
+	while (1) {
+		evt = task_wait_event(-1);
+
+		if (evt & PROCHOT_EVENT_200MS_TICK)
+			assert_prochot();
+	}
+}