[PATCH] regulator: ltc3589: Make IRQ optional

[Bernhard Walle <bernhard@bwalle.de>]

It's perfectly valid to use the LTC3589 without an interrupt pin
connected to it. Currently, the driver probing fails when client->irq
is 0 (which means "no interrupt"). Don't register the interrupt
handler in that case but successfully finish the device probing instead.

Signed-off-by: Bernhard Walle <bernhard@bwalle.de>
---
 drivers/regulator/ltc3589.c | 14 ++++++++------
 1 file changed, 8 insertions(+), 6 deletions(-)

diff --git a/drivers/regulator/ltc3589.c b/drivers/regulator/ltc3589.c
index 972c386..f2149d07 100644
--- a/drivers/regulator/ltc3589.c
+++ b/drivers/regulator/ltc3589.c
@@ -520,12 +520,14 @@ static int ltc3589_probe(struct i2c_client *client,
 		}
 	}
 
-	ret = devm_request_threaded_irq(dev, client->irq, NULL, ltc3589_isr,
-					IRQF_TRIGGER_LOW | IRQF_ONESHOT,
-					client->name, ltc3589);
-	if (ret) {
-		dev_err(dev, "Failed to request IRQ: %d\n", ret);
-		return ret;
+	if (client->irq != 0) {
+		ret = devm_request_threaded_irq(dev, client->irq, NULL, ltc3589_isr,
+						IRQF_TRIGGER_LOW | IRQF_ONESHOT,
+						client->name, ltc3589);
+		if (ret) {
+			dev_err(dev, "Failed to request IRQ %d: %d\n", client->irq, ret);
+			return ret;
+		}
 	}
 
 	return 0;
-- 
2.7.1