Merge branch 'next' into for-linus

Prepare input updates for 5.3 merge window.

1 files changed, 45 insertions, 16 deletions

diff --git a/drivers/rtc/rtc-pcf8523.c b/drivers/rtc/rtc-pcf8523.c
index 453615f8ac9a..b5c61a70b5df 100644
--- a/drivers/rtc/rtc-pcf8523.c
+++ b/drivers/rtc/rtc-pcf8523.c
@@ -85,23 +85,46 @@ static int pcf8523_write(struct i2c_client *client, u8 reg, u8 value)
 	return 0;
 }
 
-static int pcf8523_select_capacitance(struct i2c_client *client, bool high)
+static int pcf8523_voltage_low(struct i2c_client *client)
 {
 	u8 value;
 	int err;
 
+	err = pcf8523_read(client, REG_CONTROL3, &value);
+	if (err < 0)
+		return err;
+
+	return !!(value & REG_CONTROL3_BLF);
+}
+
+static int pcf8523_load_capacitance(struct i2c_client *client)
+{
+	u32 load;
+	u8 value;
+	int err;
+
 	err = pcf8523_read(client, REG_CONTROL1, &value);
 	if (err < 0)
 		return err;
 
-	if (!high)
-		value &= ~REG_CONTROL1_CAP_SEL;
-	else
+	load = 12500;
+	of_property_read_u32(client->dev.of_node, "quartz-load-femtofarads",
+			     &load);
+
+	switch (load) {
+	default:
+		dev_warn(&client->dev, "Unknown quartz-load-femtofarads value: %d. Assuming 12500",
+			 load);
+		/* fall through */
+	case 12500:
 		value |= REG_CONTROL1_CAP_SEL;
+		break;
+	case 7000:
+		value &= ~REG_CONTROL1_CAP_SEL;
+		break;
+	}
 
 	err = pcf8523_write(client, REG_CONTROL1, value);
-	if (err < 0)
-		return err;
 
 	return err;
 }
@@ -167,6 +190,14 @@ static int pcf8523_rtc_read_time(struct device *dev, struct rtc_time *tm)
 	struct i2c_msg msgs[2];
 	int err;
 
+	err = pcf8523_voltage_low(client);
+	if (err < 0) {
+		return err;
+	} else if (err > 0) {
+		dev_err(dev, "low voltage detected, time is unreliable\n");
+		return -EINVAL;
+	}
+
 	msgs[0].addr = client->addr;
 	msgs[0].flags = 0;
 	msgs[0].len = 1;
@@ -251,17 +282,13 @@ static int pcf8523_rtc_ioctl(struct device *dev, unsigned int cmd,
 			     unsigned long arg)
 {
 	struct i2c_client *client = to_i2c_client(dev);
-	u8 value;
-	int ret = 0, err;
+	int ret;
 
 	switch (cmd) {
 	case RTC_VL_READ:
-		err = pcf8523_read(client, REG_CONTROL3, &value);
-		if (err < 0)
-			return err;
-
-		if (value & REG_CONTROL3_BLF)
-			ret = 1;
+		ret = pcf8523_voltage_low(client);
+		if (ret < 0)
+			return ret;
 
 		if (copy_to_user((void __user *)arg, &ret, sizeof(int)))
 			return -EFAULT;
@@ -331,9 +358,10 @@ static int pcf8523_probe(struct i2c_client *client,
 	if (!pcf)
 		return -ENOMEM;
 
-	err = pcf8523_select_capacitance(client, true);
+	err = pcf8523_load_capacitance(client);
 	if (err < 0)
-		return err;
+		dev_warn(&client->dev, "failed to set xtal load capacitance: %d",
+			 err);
 
 	err = pcf8523_set_pm(client, 0);
 	if (err < 0)
@@ -358,6 +386,7 @@ MODULE_DEVICE_TABLE(i2c, pcf8523_id);
 #ifdef CONFIG_OF
 static const struct of_device_id pcf8523_of_match[] = {
 	{ .compatible = "nxp,pcf8523" },
+	{ .compatible = "microcrystal,rv8523" },
 	{ }
 };
 MODULE_DEVICE_TABLE(of, pcf8523_of_match);