rtc: hym8563: enable wakeup when applicable

Enable wakeup in the hym8563 driver if the IRQ was successfully
requested or if wakeup-source is set in the devicetree.

As per the description of device_init_wakeup(), it should be enabled
for "devices that everyone expects to be wakeup sources".  One would
expect this to be the case with a real-time clock.

Tested on rk3288-rock2-square, which has an IRQ configured for the
RTC.  As a result, wakeup was enabled during driver initialisation.

Fixes: dcaf0384 ("rtc: add hym8563 rtc-driver")
Reported-by: kernelci.org bot <bot@kernelci.org>
Signed-off-by: Guillaume Tucker <guillaume.tucker@collabora.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lore.kernel.org/r/1ea023e2ba50a4dab6e39be93d7de3146af71a60.1604653374.git.guillaume.tucker@collabora.com

drivers/rtc/rtc-hym8563.c

@@ -527,8 +527,6 @@ static int hym8563_probe(struct i2c_client *client,
 	hym8563->client = client;
 	i2c_set_clientdata(client, hym8563);
 
-	device_set_wakeup_capable(&client->dev, true);
-
 	ret = hym8563_init_device(client);
 	if (ret) {
 		dev_err(&client->dev, "could not init device, %d\n", ret);
@@ -547,6 +545,11 @@ static int hym8563_probe(struct i2c_client *client,
 		}
 	}
 
+	if (client->irq > 0 ||
+	    device_property_read_bool(&client->dev, "wakeup-source")) {
+		device_init_wakeup(&client->dev, true);
+	}
+
 	/* check state of calendar information */
 	ret = i2c_smbus_read_byte_data(client, HYM8563_SEC);
 	if (ret < 0)