rtc: s5m: signal the core when alarm are not available

Clear the RTC_FEATURE_ALARM bit to signal to the core when alarms are not
available to ensure the alarm callbacks are never called and userspace is
aware alarms are not supported.

Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
Link: https://lore.kernel.org/r/20210804104133.5158-2-alexandre.belloni@bootlin.com

diff --git a/drivers/rtc/rtc-s5m.c b/drivers/rtc/rtc-s5m.c
index 4c1596c55de89c5d0add1b38f872c76323fb7aa2..ee195697e6c6db7f1b2bda3650bcb53a402323da 100644 (file)
--- a/drivers/rtc/rtc-s5m.c
+++ b/drivers/rtc/rtc-s5m.c
@@ -794,25 +794,20 @@ static int s5m_rtc_probe(struct platform_device *pdev)
 
        info->rtc_dev->ops = &s5m_rtc_ops;
 
-       err = devm_rtc_register_device(info->rtc_dev);
-       if (err)
-               return err;
-
        if (!info->irq) {
-               dev_info(&pdev->dev, "Alarm IRQ not available\n");
-               return 0;
-       }
-
-       ret = devm_request_threaded_irq(&pdev->dev, info->irq, NULL,
-                                       s5m_rtc_alarm_irq, 0, "rtc-alarm0",
-                                       info);
-       if (ret < 0) {
-               dev_err(&pdev->dev, "Failed to request alarm IRQ: %d: %d\n",
-                       info->irq, ret);
-               return ret;
+               clear_bit(RTC_FEATURE_ALARM, info->rtc_dev->features);
+       } else {
+               ret = devm_request_threaded_irq(&pdev->dev, info->irq, NULL,
+                                               s5m_rtc_alarm_irq, 0, "rtc-alarm0",
+                                               info);
+               if (ret < 0) {
+                       dev_err(&pdev->dev, "Failed to request alarm IRQ: %d: %d\n",
+                               info->irq, ret);
+                       return ret;
+               }
        }
 
-       return 0;
+       return devm_rtc_register_device(info->rtc_dev);
 }
 
 #ifdef CONFIG_PM_SLEEP