rtc: rv8803: return meaningful value for RTC_VL_READ

RV8803_FLAG_V1F means the voltage is too low to keep the temperature
compensation running and the accuracy of the RTC is affected.

RV8803_FLAG_V2F means the voltage dropped so low that data is now invalid.

Link: https://lore.kernel.org/r/20191214220259.621996-16-alexandre.belloni@bootlin.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

diff --git a/drivers/rtc/rtc-rv8803.c b/drivers/rtc/rtc-rv8803.c
index ed92116..93c3a6b 100644 (file)
--- a/drivers/rtc/rtc-rv8803.c
+++ b/drivers/rtc/rtc-rv8803.c
@@ -411,6 +411,7 @@ static int rv8803_ioctl(struct device *dev, unsigned int cmd, unsigned long arg)
 {
        struct i2c_client *client = to_i2c_client(dev);
        struct rv8803_data *rv8803 = dev_get_drvdata(dev);
+       unsigned int vl = 0;
        int flags, ret = 0;
 
        switch (cmd) {
@@ -419,18 +420,15 @@ static int rv8803_ioctl(struct device *dev, unsigned int cmd, unsigned long arg)
                if (flags < 0)
                        return flags;
 
-               if (flags & RV8803_FLAG_V1F)
+               if (flags & RV8803_FLAG_V1F) {
                        dev_warn(&client->dev, "Voltage low, temperature compensation stopped.\n");
+                       vl = RTC_VL_ACCURACY_LOW;
+               }
 
                if (flags & RV8803_FLAG_V2F)
-                       dev_warn(&client->dev, "Voltage low, data loss detected.\n");
-
-               flags &= RV8803_FLAG_V1F | RV8803_FLAG_V2F;
+                       vl |= RTC_VL_DATA_INVALID;
 
-               if (copy_to_user((void __user *)arg, &flags, sizeof(int)))
-                       return -EFAULT;
-
-               return 0;
+               return put_user(vl, (unsigned int __user *)arg);
 
        case RTC_VL_CLR:
                mutex_lock(&rv8803->flags_lock);