rtc: cmos: Do not require IRQ if ACPI alarm is used

If the ACPI RTC fixed event is used, a dedicated IRQ is not required
for the CMOS RTC alarm to work, so allow the driver to use the alarm
without a valid IRQ in that case.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Reviewed-by: Mario Limonciello (AMD) <superm1@kernel.org>
Link: https://patch.msgid.link/6168746.MhkbZ0Pkbq@rafael.j.wysocki

diff --git a/drivers/rtc/rtc-cmos.c b/drivers/rtc/rtc-cmos.c
index 221e7525cd3fb49f2ac72581fc283faf41736773..acc064baefcd275ed3ee0cdbfd26e39024513154 100644 (file)
--- a/drivers/rtc/rtc-cmos.c
+++ b/drivers/rtc/rtc-cmos.c
@@ -216,6 +216,11 @@ static inline void cmos_write_bank2(unsigned char val, unsigned char addr)
 
 /*----------------------------------------------------------------*/
 
+static bool cmos_no_alarm(struct cmos_rtc *cmos)
+{
+       return !is_valid_irq(cmos->irq) && !cmos_use_acpi_alarm();
+}
+
 static int cmos_read_time(struct device *dev, struct rtc_time *t)
 {
        int ret;
@@ -287,7 +292,7 @@ static int cmos_read_alarm(struct device *dev, struct rtc_wkalrm *t)
        };
 
        /* This not only a rtc_op, but also called directly */
-       if (!is_valid_irq(cmos->irq))
+       if (cmos_no_alarm(cmos))
                return -ETIMEDOUT;
 
        /* Basic alarms only support hour, minute, and seconds fields.
@@ -520,7 +525,7 @@ static int cmos_set_alarm(struct device *dev, struct rtc_wkalrm *t)
        int ret;
 
        /* This not only a rtc_op, but also called directly */
-       if (!is_valid_irq(cmos->irq))
+       if (cmos_no_alarm(cmos))
                return -EIO;
 
        ret = cmos_validate_alarm(dev, t);
@@ -1096,7 +1101,7 @@ cmos_do_probe(struct device *dev, struct resource *ports, int rtc_irq)
                        dev_dbg(dev, "IRQ %d is already in use\n", rtc_irq);
                        goto cleanup1;
                }
-       } else {
+       } else if (!cmos_use_acpi_alarm()) {
                clear_bit(RTC_FEATURE_ALARM, cmos_rtc.rtc->features);
        }
 
@@ -1121,7 +1126,7 @@ cmos_do_probe(struct device *dev, struct resource *ports, int rtc_irq)
                acpi_rtc_event_setup(dev);
 
        dev_info(dev, "%s%s, %d bytes nvram%s\n",
-                !is_valid_irq(rtc_irq) ? "no alarms" :
+                cmos_no_alarm(&cmos_rtc) ? "no alarms" :
                 cmos_rtc.mon_alrm ? "alarms up to one year" :
                 cmos_rtc.day_alrm ? "alarms up to one month" :
                 "alarms up to one day",
@@ -1147,7 +1152,7 @@ cleanup0:
 static void cmos_do_shutdown(int rtc_irq)
 {
        spin_lock_irq(&rtc_lock);
-       if (is_valid_irq(rtc_irq))
+       if (!cmos_no_alarm(&cmos_rtc))
                cmos_irq_disable(&cmos_rtc, RTC_IRQMASK);
        spin_unlock_irq(&rtc_lock);
 }