1 files changed, 38 insertions, 0 deletions

diff --git a/drivers/rtc/rtc-abx80x.c b/drivers/rtc/rtc-abx80x.c
index d8e94edcb0ba..4d24f7288ad7 100644
--- a/drivers/rtc/rtc-abx80x.c
+++ b/drivers/rtc/rtc-abx80x.c
@@ -38,6 +38,7 @@
 
 #define ABX8XX_REG_STATUS       0x0f
 #define ABX8XX_STATUS_AF        BIT(2)
+#define ABX8XX_STATUS_BLF       BIT(4)
 #define ABX8XX_STATUS_WDT       BIT(6)
 
 #define ABX8XX_REG_CTRL1        0x10
@@ -507,12 +508,49 @@ static int abx80x_alarm_irq_enable(struct device *dev, unsigned int enabled)
         return err;
 }
 
+static int abx80x_ioctl(struct device *dev, unsigned int cmd, unsigned long arg)
+{
+        struct i2c_client *client = to_i2c_client(dev);
+        int status, tmp;
+
+        switch (cmd) {
+        case RTC_VL_READ:
+                status = i2c_smbus_read_byte_data(client, ABX8XX_REG_STATUS);
+                if (status < 0)
+                        return status;
+
+                tmp = !!(status & ABX8XX_STATUS_BLF);
+
+                if (copy_to_user((void __user *)arg, &tmp, sizeof(int)))
+                        return -EFAULT;
+
+                return 0;
+
+        case RTC_VL_CLR:
+                status = i2c_smbus_read_byte_data(client, ABX8XX_REG_STATUS);
+                if (status < 0)
+                        return status;
+
+                status &= ~ABX8XX_STATUS_BLF;
+
+                tmp = i2c_smbus_write_byte_data(client, ABX8XX_REG_STATUS, 0);
+                if (tmp < 0)
+                        return tmp;
+
+                return 0;
+
+        default:
+                return -ENOIOCTLCMD;
+        }
+}
+
 static const struct rtc_class_ops abx80x_rtc_ops = {
         .read_time      = abx80x_rtc_read_time,
         .set_time       = abx80x_rtc_set_time,
         .read_alarm     = abx80x_read_alarm,
         .set_alarm      = abx80x_set_alarm,
         .alarm_irq_enable = abx80x_alarm_irq_enable,
+        .ioctl          = abx80x_ioctl,
 };
 
 static int abx80x_dt_trickle_cfg(struct device_node *np)