--- zzzz-none-000/linux-3.10.107/drivers/rtc/rtc-ds3232.c	2017-06-27 09:49:32.000000000 +0000
+++ scorpion-7490-727/linux-3.10.107/drivers/rtc/rtc-ds3232.c	2021-02-04 17:41:59.000000000 +0000
@@ -15,6 +15,8 @@
  * "Sending and receiving", using SMBus level communication is preferred.
  */
 
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
 #include <linux/kernel.h>
 #include <linux/module.h>
 #include <linux/interrupt.h>
@@ -57,6 +59,7 @@
 	 * in the remove function.
 	 */
 	struct mutex mutex;
+	bool suspended;
 	int exiting;
 };
 
@@ -345,7 +348,15 @@
 	struct ds3232 *ds3232 = i2c_get_clientdata(client);
 
 	disable_irq_nosync(irq);
-	schedule_work(&ds3232->work);
+
+	/*
+	 * If rtc as a wakeup source, can't schedule the work
+	 * at system resume flow, because at this time the i2c bus
+	 * has not been resumed.
+	 */
+	if (!ds3232->suspended)
+		schedule_work(&ds3232->work);
+
 	return IRQ_HANDLED;
 }
 
@@ -363,22 +374,26 @@
 
 	if (stat & DS3232_REG_SR_A1F) {
 		control = i2c_smbus_read_byte_data(client, DS3232_REG_CR);
-		if (control < 0)
-			goto out;
-		/* disable alarm1 interrupt */
-		control &= ~(DS3232_REG_CR_A1IE);
-		i2c_smbus_write_byte_data(client, DS3232_REG_CR, control);
+		if (control < 0) {
+			pr_warn("Read Control Register error - Disable IRQ%d\n",
+				client->irq);
+		} else {
+			/* disable alarm1 interrupt */
+			control &= ~(DS3232_REG_CR_A1IE);
+			i2c_smbus_write_byte_data(client, DS3232_REG_CR,
+						control);
+
+			/* clear the alarm pend flag */
+			stat &= ~DS3232_REG_SR_A1F;
+			i2c_smbus_write_byte_data(client, DS3232_REG_SR, stat);
 
-		/* clear the alarm pend flag */
-		stat &= ~DS3232_REG_SR_A1F;
-		i2c_smbus_write_byte_data(client, DS3232_REG_SR, stat);
+			rtc_update_irq(ds3232->rtc, 1, RTC_AF | RTC_IRQF);
 
-		rtc_update_irq(ds3232->rtc, 1, RTC_AF | RTC_IRQF);
+			if (!ds3232->exiting)
+				enable_irq(client->irq);
+		}
 	}
 
-out:
-	if (!ds3232->exiting)
-		enable_irq(client->irq);
 unlock:
 	mutex_unlock(&ds3232->mutex);
 }
@@ -411,30 +426,24 @@
 	if (ret)
 		return ret;
 
-	ds3232->rtc = devm_rtc_device_register(&client->dev, client->name,
-					  &ds3232_rtc_ops, THIS_MODULE);
-	if (IS_ERR(ds3232->rtc)) {
-		dev_err(&client->dev, "unable to register the class device\n");
-		return PTR_ERR(ds3232->rtc);
-	}
-
-	if (client->irq >= 0) {
-		ret = devm_request_irq(&client->dev, client->irq, ds3232_irq, 0,
-				 "ds3232", client);
+	if (client->irq > 0) {
+		ret = devm_request_irq(&client->dev, client->irq, ds3232_irq,
+				       IRQF_SHARED, "ds3232", client);
 		if (ret) {
 			dev_err(&client->dev, "unable to request IRQ\n");
-			return ret;
 		}
+		device_init_wakeup(&client->dev, 1);
 	}
-
-	return 0;
+	ds3232->rtc = devm_rtc_device_register(&client->dev, client->name,
+					  &ds3232_rtc_ops, THIS_MODULE);
+	return PTR_ERR_OR_ZERO(ds3232->rtc);
 }
 
 static int ds3232_remove(struct i2c_client *client)
 {
 	struct ds3232 *ds3232 = i2c_get_clientdata(client);
 
-	if (client->irq >= 0) {
+	if (client->irq > 0) {
 		mutex_lock(&ds3232->mutex);
 		ds3232->exiting = 1;
 		mutex_unlock(&ds3232->mutex);
@@ -446,6 +455,45 @@
 	return 0;
 }
 
+#ifdef CONFIG_PM_SLEEP
+static int ds3232_suspend(struct device *dev)
+{
+	struct ds3232 *ds3232 = dev_get_drvdata(dev);
+	struct i2c_client *client = to_i2c_client(dev);
+
+	if (device_can_wakeup(dev)) {
+		ds3232->suspended = true;
+		if (irq_set_irq_wake(client->irq, 1)) {
+			dev_warn_once(dev, "Cannot set wakeup source\n");
+			ds3232->suspended = false;
+		}
+	}
+
+	return 0;
+}
+
+static int ds3232_resume(struct device *dev)
+{
+	struct ds3232 *ds3232 = dev_get_drvdata(dev);
+	struct i2c_client *client = to_i2c_client(dev);
+
+	if (ds3232->suspended) {
+		ds3232->suspended = false;
+
+		/* Clear the hardware alarm pend flag */
+		schedule_work(&ds3232->work);
+
+		irq_set_irq_wake(client->irq, 0);
+	}
+
+	return 0;
+}
+#endif
+
+static const struct dev_pm_ops ds3232_pm_ops = {
+	SET_SYSTEM_SLEEP_PM_OPS(ds3232_suspend, ds3232_resume)
+};
+
 static const struct i2c_device_id ds3232_id[] = {
 	{ "ds3232", 0 },
 	{ }
@@ -455,7 +503,7 @@
 static struct i2c_driver ds3232_driver = {
 	.driver = {
 		.name = "rtc-ds3232",
-		.owner = THIS_MODULE,
+		.pm	= &ds3232_pm_ops,
 	},
 	.probe = ds3232_probe,
 	.remove = ds3232_remove,