rtc: max77686: Properly handle regmap_irq_get_virq() error code

[ Upstream commit fb166ba1d7f0a662f7332f4ff660a0d6f4d76915 ]

The regmap_irq_get_virq() can return 0 or -EINVAL in error conditions
but driver checked only for value of 0.

This could lead to a cast of -EINVAL to an unsigned int used as a
interrupt number for devm_request_threaded_irq(). Although this is not
yet fatal (devm_request_threaded_irq() will just fail with -EINVAL) but
might be a misleading when diagnosing errors.

Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Fixes: 6f1c1e71d933 ("mfd: max77686: Convert to use regmap_irq")
Reviewed-by: Javier Martinez Canillas <javier@osg.samsung.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>

diff --git a/drivers/rtc/rtc-max77686.c b/drivers/rtc/rtc-max77686.c
index 7632a87..d42cef0 100644 (file)
--- a/drivers/rtc/rtc-max77686.c
+++ b/drivers/rtc/rtc-max77686.c
@@ -465,7 +465,7 @@ static int max77686_rtc_probe(struct platform_device *pdev)
 
        info->virq = regmap_irq_get_virq(max77686->rtc_irq_data,
                                         MAX77686_RTCIRQ_RTCA1);
-       if (!info->virq) {
+       if (info->virq <= 0) {
                ret = -ENXIO;
                goto err_rtc;
        }