diff --git a/drivers/rtc/rtc-m41t80.c b/drivers/rtc/rtc-m41t80.c
index f963b76e5fc0..85bde7130a4d 100644
--- a/drivers/rtc/rtc-m41t80.c
+++ b/drivers/rtc/rtc-m41t80.c
@@ -44,12 +44,17 @@
 #define M41T80_REG_ALARM_MIN	0x0d
 #define M41T80_REG_ALARM_SEC	0x0e
 #define M41T80_REG_FLAGS	0x0f
+#define M41T80_REG_AC		0x12
 #define M41T80_REG_SQW		0x13
 
 #define M41T80_DATETIME_REG_SIZE	(M41T80_REG_YEAR + 1)
 #define M41T80_ALARM_REG_SIZE	\
 	(M41T80_REG_ALARM_SEC + 1 - M41T80_REG_ALARM_MON)
 
+#define M41T80_AC_MIN		 3500
+#define M41T80_AC_MAX		17375
+#define M41T80_AC_DEFAULT	12500
+
 #define M41T80_SQW_MAX_FREQ	32768
 
 #define M41T80_SEC_ST		BIT(7)	/* ST: Stop Bit */
@@ -68,6 +73,7 @@
 #define M41T80_FEATURE_SQ	BIT(2)	/* Squarewave feature */
 #define M41T80_FEATURE_WD	BIT(3)	/* Extra watchdog resolution */
 #define M41T80_FEATURE_SQ_ALT	BIT(4)	/* RSx bits are in reg 4 */
+#define M41T80_FEATURE_AC	BIT(5) /* Analog calibration */
 
 static const struct i2c_device_id m41t80_id[] = {
 	{ "m41t62", M41T80_FEATURE_SQ | M41T80_FEATURE_SQ_ALT },
@@ -75,8 +81,10 @@ static const struct i2c_device_id m41t80_id[] = {
 	{ "m41t80", M41T80_FEATURE_SQ },
 	{ "m41t81", M41T80_FEATURE_HT | M41T80_FEATURE_SQ},
 	{ "m41t81s", M41T80_FEATURE_HT | M41T80_FEATURE_BL | M41T80_FEATURE_SQ },
-	{ "m41t82", M41T80_FEATURE_HT | M41T80_FEATURE_BL | M41T80_FEATURE_SQ },
-	{ "m41t83", M41T80_FEATURE_HT | M41T80_FEATURE_BL | M41T80_FEATURE_SQ },
+	{ "m41t82", M41T80_FEATURE_HT | M41T80_FEATURE_BL | M41T80_FEATURE_SQ
+		    | M41T80_FEATURE_AC },
+	{ "m41t83", M41T80_FEATURE_HT | M41T80_FEATURE_BL | M41T80_FEATURE_SQ
+		    | M41T80_FEATURE_AC },
 	{ "m41st84", M41T80_FEATURE_HT | M41T80_FEATURE_BL | M41T80_FEATURE_SQ },
 	{ "m41st85", M41T80_FEATURE_HT | M41T80_FEATURE_BL | M41T80_FEATURE_SQ },
 	{ "m41st87", M41T80_FEATURE_HT | M41T80_FEATURE_BL | M41T80_FEATURE_SQ },
@@ -108,11 +116,13 @@ static const __maybe_unused struct of_device_id m41t80_of_match[] = {
 	},
 	{
 		.compatible = "st,m41t82",
-		.data = (void *)(M41T80_FEATURE_HT | M41T80_FEATURE_BL | M41T80_FEATURE_SQ)
+		.data = (void *)(M41T80_FEATURE_HT | M41T80_FEATURE_BL | M41T80_FEATURE_SQ
+				 | M41T80_FEATURE_AC)
 	},
 	{
 		.compatible = "st,m41t83",
-		.data = (void *)(M41T80_FEATURE_HT | M41T80_FEATURE_BL | M41T80_FEATURE_SQ)
+		.data = (void *)(M41T80_FEATURE_HT | M41T80_FEATURE_BL | M41T80_FEATURE_SQ
+				 | M41T80_FEATURE_AC)
 	},
 	{
 		.compatible = "st,m41t84",
@@ -405,6 +415,54 @@ static const struct rtc_class_ops m41t80_rtc_ops = {
 	.alarm_irq_enable = m41t80_alarm_irq_enable,
 };
 
+static u8 to_sign_magnitude_u8(int n)
+{
+	if (n < 0)
+		return 0x80 | -n;
+	return n;
+}
+
+static int m41t80_encode_ac(int quartz_load)
+{
+	if (quartz_load < M41T80_AC_MIN || quartz_load > M41T80_AC_MAX)
+		return -EINVAL;
+
+	/*
+	 * register representation is the per-capacitor offset from its default
+	 * value in units of 1/4 pF, in sign-magnitude form.
+	 */
+	return to_sign_magnitude_u8((quartz_load - M41T80_AC_DEFAULT) / 125);
+}
+
+static int m41t80_set_ac(struct m41t80_data *m41t80_data, int quartz_load)
+{
+	struct i2c_client *client = m41t80_data->client;
+	struct device *dev = &client->dev;
+	int ret;
+	int ac;
+
+	if (!(m41t80_data->features & M41T80_FEATURE_AC)) {
+		dev_err(dev, "analog calibration requested but not supported\n");
+		return -EOPNOTSUPP;
+	}
+
+	ac = m41t80_encode_ac(quartz_load);
+	if (ac < 0) {
+		dev_err(dev, "quartz load %d fF out of range\n",
+			quartz_load);
+		return ac;
+	}
+
+	ret = i2c_smbus_write_byte_data(client, M41T80_REG_AC, ac);
+	if (ret < 0) {
+		dev_err(dev, "Can't set AC register\n");
+		return ret;
+	}
+
+	dev_info(dev, "quartz load set to %d fF (AC=0x%x)\n", quartz_load, ac);
+	return 0;
+}
+
 #ifdef CONFIG_PM_SLEEP
 static int m41t80_suspend(struct device *dev)
 {
@@ -883,6 +941,7 @@ static int m41t80_probe(struct i2c_client *client)
 	struct rtc_time tm;
 	struct m41t80_data *m41t80_data = NULL;
 	bool wakeup_source = false;
+	u32 quartz_load = M41T80_AC_DEFAULT;
 
 	if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_I2C_BLOCK |
 				     I2C_FUNC_SMBUS_BYTE_DATA)) {
@@ -912,6 +971,14 @@ static int m41t80_probe(struct i2c_client *client)
 	if (IS_ENABLED(CONFIG_OF)) {
 		wakeup_source = of_property_read_bool(client->dev.of_node,
 						      "wakeup-source");
+
+		rc = of_property_read_u32(client->dev.of_node,
+					  "quartz-load-femtofarads",
+					  &quartz_load);
+		if (!rc)
+			m41t80_set_ac(m41t80_data, quartz_load);
+		else if (rc != -EINVAL)
+			dev_err(&client->dev, "quartz-load-femtofarads property value is missing or invalid\n");
 	}
 
 	if (client->irq > 0) {
