linux-kernel - [PATCH V1 3/3] power: supply: sbs-battery: Add optional status monitoring

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Message-ID: <20251229085636.4082852-3-Qing-wu.Li@leica-geosystems.com.cn>
Date: Mon, 29 Dec 2025 08:56:36 +0000
From: LI Qingwu <Qing-wu.Li@...ca-geosystems.com.cn>
To: sre@...nel.org,
	robh@...nel.org,
	krzk+dt@...nel.org,
	conor+dt@...nel.org,
	linux-pm@...r.kernel.org,
	devicetree@...r.kernel.org,
	linux-kernel@...r.kernel.org
Cc: bsp-development.geo@...ca-geosystems.com,
	LI Qingwu <Qing-wu.Li@...ca-geosystems.com.cn>
Subject: [PATCH V1 3/3] power: supply: sbs-battery: Add optional status monitoring

Some systems do not have GPIO interrupt support for battery detection.
Without GPIO IRQ or SMBus Alert, the driver cannot proactively report
battery status changes.

Add an optional "sbs,monitoring-interval-ms" device property to enable
periodic status checks. When set, the driver polls the SBS status
register at the given interval and calls power_supply_changed() if the
battery state changes.

If a GPIO IRQ is successfully registered, monitoring is automatically
disabled since interrupt-based detection is preferred.

Signed-off-by: LI Qingwu <Qing-wu.Li@...ca-geosystems.com.cn>
---
 drivers/power/supply/sbs-battery.c | 50 ++++++++++++++++++++++--------
 1 file changed, 37 insertions(+), 13 deletions(-)

diff --git a/drivers/power/supply/sbs-battery.c b/drivers/power/supply/sbs-battery.c
index 9537b692f9fd..2874a741c809 100644
--- a/drivers/power/supply/sbs-battery.c
+++ b/drivers/power/supply/sbs-battery.c
@@ -214,6 +214,7 @@ struct sbs_info {
 	u32				poll_retry_count;
 	struct delayed_work		work;
 	struct mutex			mode_lock;
+	u32				monitoring_interval_ms;
 	u32				flags;
 	int				technology;
 	char				strings[NR_STRING_BUFFERS][I2C_SMBUS_BLOCK_MAX + 1];
@@ -1089,21 +1090,27 @@ static void sbs_delayed_work(struct work_struct *work)
 	/* if the read failed, give up on this work */
 	if (ret < 0) {
 		chip->poll_time = 0;
-		return;
-	}
-
-	if (ret & BATTERY_FULL_CHARGED)
-		ret = POWER_SUPPLY_STATUS_FULL;
-	else if (ret & BATTERY_DISCHARGING)
-		ret = POWER_SUPPLY_STATUS_DISCHARGING;
-	else
-		ret = POWER_SUPPLY_STATUS_CHARGING;
+		if (!chip->monitoring_interval_ms)
+			return;
+	} else {
+		if (ret & BATTERY_FULL_CHARGED)
+			ret = POWER_SUPPLY_STATUS_FULL;
+		else if (ret & BATTERY_DISCHARGING)
+			ret = POWER_SUPPLY_STATUS_DISCHARGING;
+		else
+			ret = POWER_SUPPLY_STATUS_CHARGING;
 
-	sbs_status_correct(chip->client, &ret);
+		sbs_status_correct(chip->client, &ret);
 
-	if (chip->last_state != ret) {
-		chip->poll_time = 0;
-		power_supply_changed(chip->power_supply);
+		if (chip->last_state != ret) {
+			chip->poll_time = 0;
+			power_supply_changed(chip->power_supply);
+		}
+	}
+	if (chip->monitoring_interval_ms) {
+		schedule_delayed_work(
+			&chip->work,
+			msecs_to_jiffies(chip->monitoring_interval_ms));
 		return;
 	}
 	if (chip->poll_time > 0) {
@@ -1171,6 +1178,13 @@ static int sbs_probe(struct i2c_client *client)
 	}
 	chip->i2c_retry_count = chip->i2c_retry_count + 1;
 
+	rc = device_property_read_u32(&client->dev, "sbs,monitoring-interval-ms",
+				      &chip->monitoring_interval_ms);
+	if (rc)
+		chip->monitoring_interval_ms = 0;
+	if (chip->monitoring_interval_ms)
+		force_load = true;
+
 	chip->charger_broadcasts = !device_property_read_bool(&client->dev,
 					"sbs,disable-charger-broadcasts");
 
@@ -1198,6 +1212,11 @@ static int sbs_probe(struct i2c_client *client)
 		dev_warn(&client->dev, "Failed to request irq: %d\n", rc);
 		goto skip_gpio;
 	}
+	if (chip->monitoring_interval_ms) {
+		dev_info(&client->dev,
+			 "GPIO IRQ registered, monitoring disabled\n");
+		chip->monitoring_interval_ms = 0;
+	}
 
 skip_gpio:
 	/*
@@ -1228,6 +1247,11 @@ static int sbs_probe(struct i2c_client *client)
 	dev_info(&client->dev,
 		"%s: battery gas gauge device registered\n", client->name);
 
+	if (chip->monitoring_interval_ms > 0)
+		schedule_delayed_work(
+			&chip->work,
+			msecs_to_jiffies(chip->monitoring_interval_ms));
+
 	return 0;
 }
 
-- 
2.43.0