[PATCH] rtc: hym8563: make the irq optional

["Heiko Stübner" <heiko@sntech.de>]

Sometimes the irq line is not connected to any soc-pin. This does
not hinder basic timekeeping functionality of the rtc, so probe
should not fail in this case.

Signed-off-by: Heiko Stuebner <heiko@sntech.de>
---
 .../devicetree/bindings/rtc/haoyu,hym8563.txt          |  2 +-
 drivers/rtc/rtc-hym8563.c                              | 18 ++++++++++--------
 2 files changed, 11 insertions(+), 9 deletions(-)

diff --git a/Documentation/devicetree/bindings/rtc/haoyu,hym8563.txt b/Documentation/devicetree/bindings/rtc/haoyu,hym8563.txt
index 5c199ee..a8934fe 100644
--- a/Documentation/devicetree/bindings/rtc/haoyu,hym8563.txt
+++ b/Documentation/devicetree/bindings/rtc/haoyu,hym8563.txt
@@ -6,11 +6,11 @@ as well as a clock output of up to 32kHz.
 Required properties:
 - compatible: should be: "haoyu,hym8563"
 - reg: i2c address
-- interrupts: rtc alarm/event interrupt
 - #clock-cells: the value should be 0
 
 Optional properties:
 - clock-output-names: From common clock binding
+- interrupts: rtc alarm/event interrupt
 
 Example:
 
diff --git a/drivers/rtc/rtc-hym8563.c b/drivers/rtc/rtc-hym8563.c
index 0f710e9..e9da795 100644
--- a/drivers/rtc/rtc-hym8563.c
+++ b/drivers/rtc/rtc-hym8563.c
@@ -548,14 +548,16 @@ static int hym8563_probe(struct i2c_client *client,
 		return ret;
 	}
 
-	ret = devm_request_threaded_irq(&client->dev, client->irq,
-					NULL, hym8563_irq,
-					IRQF_TRIGGER_LOW | IRQF_ONESHOT,
-					client->name, hym8563);
-	if (ret < 0) {
-		dev_err(&client->dev, "irq %d request failed, %d\n",
-			client->irq, ret);
-		return ret;
+	if (client->irq > 0) {
+		ret = devm_request_threaded_irq(&client->dev, client->irq,
+						NULL, hym8563_irq,
+						IRQF_TRIGGER_LOW | IRQF_ONESHOT,
+						client->name, hym8563);
+		if (ret < 0) {
+			dev_err(&client->dev, "irq %d request failed, %d\n",
+				client->irq, ret);
+			return ret;
+		}
 	}
 
 	/* check state of calendar information */
-- 
2.1.4