From: Mirza Krak <>

Add a sanity check to see if chip is present. If we can not communicate
with the chip there is no point in registering a RTC device.

Signed-off-by: Mirza Krak <>
 drivers/rtc/rtc-pcf85063.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/drivers/rtc/rtc-pcf85063.c b/drivers/rtc/rtc-pcf85063.c
index efb0a08..a06dff9 100644
--- a/drivers/rtc/rtc-pcf85063.c
+++ b/drivers/rtc/rtc-pcf85063.c
@@ -191,12 +191,19 @@ static int pcf85063_probe(struct i2c_client *client,
                                const struct i2c_device_id *id)
        struct rtc_device *rtc;
+       int err;
        dev_dbg(&client->dev, "%s\n", __func__);
        if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C))
                return -ENODEV;
+       err = i2c_smbus_read_byte_data(client, PCF85063_REG_CTRL1);
+       if (err < 0) {
+               dev_err(&client->dev, "RTC chip is not present\n");
+               return err;
+       }
        rtc = devm_rtc_device_register(&client->dev,
                                       &pcf85063_rtc_ops, THIS_MODULE);

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