rtc: pcf85063: do not register a RTC device if chip is not present
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 <mirza.krak@hostmobility.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
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_driver.driver.name,
&pcf85063_rtc_ops, THIS_MODULE);