[PATCH] rtc: as3722: check return value of platform_get_irq()

[Akshat Rawat <akshatrawat095@gmail.com>]

In as3722_rtc_probe(), the return value of platform_get_irq() is
assigned to as3722_rtc->alarm_irq without error checking.

If platform_get_irq() fails (such as returning -EPROBE_DEFER when the
parent interrupt controller is not yet ready), the driver logs an
invalid IRQ number in dev_info() and calls devm_request_threaded_irq()
with a negative value. This causes devm_request_threaded_irq() to fail
with -EINVAL and abort probe permanently, breaking deferred probing.

Check the return value of platform_get_irq() and return immediately on
failure to properly propagate errors.

Fixes: b45062619840 ("drivers/rtc/rtc-as3722: add RTC driver")
Cc: stable@vger.kernel.org
Signed-off-by: Akshat Rawat <akshatrawat095@gmail.com>
---
 drivers/rtc/rtc-as3722.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/rtc/rtc-as3722.c b/drivers/rtc/rtc-as3722.c
index 9682d6457b7f..dfa3628ad95b 100644
--- a/drivers/rtc/rtc-as3722.c
+++ b/drivers/rtc/rtc-as3722.c
@@ -198,6 +198,9 @@ static int as3722_rtc_probe(struct platform_device *pdev)
 	}
 
 	as3722_rtc->alarm_irq = platform_get_irq(pdev, 0);
+	if (as3722_rtc->alarm_irq < 0)
+		return as3722_rtc->alarm_irq;
+
 	dev_info(&pdev->dev, "RTC interrupt %d\n", as3722_rtc->alarm_irq);
 
 	ret = devm_request_threaded_irq(&pdev->dev, as3722_rtc->alarm_irq, NULL,
-- 
2.56.0.windows.4