Merge tag 'rtc-5.16' of git://git.kernel.org/pub/scm/linux/kernel/git/abelloni/linux

Pull RTC updates from Alexandre Belloni:
 "This includes new ioctls to get and set parameters and in particular
  the backup switch mode that is needed for some RTCs to actually enable
  the backup voltage (and have a useful RTC).

  The same interface can also be used to get the actual features
  supported by the RTC so userspace has a better way than trying and
  failing.

  Summary:

  Subsystem:
   - Add new ioctl to get and set extra RTC parameters, this includes
     backup switch mode
   - Expose available features to userspace, in particular, when alarmas
     have a resolution of one minute instead of a second.
   - Let the core handle those alarms with a minute resolution

  New driver:
   - MSTAR MSC313 RTC

  Drivers:
   - Add SPI ID table where necessary
   - Add BSM support for rv3028, rv3032 and pcf8523
   - s3c: set RTC range
   - rx8025: set range, implement .set_offset and .read_offset"

* tag 'rtc-5.16' of git://git.kernel.org/pub/scm/linux/kernel/git/abelloni/linux: (50 commits)
  rtc: rx8025: use .set_offset/.read_offset
  rtc: rx8025: use rtc_add_group
  rtc: rx8025: clear RTC_FEATURE_ALARM when alarm are not supported
  rtc: rx8025: set range
  rtc: rx8025: let the core handle the alarm resolution
  rtc: rx8025: switch to devm_rtc_allocate_device
  rtc: ab8500: let the core handle the alarm resolution
  rtc: ab-eoz9: support UIE when available
  rtc: ab-eoz9: use RTC_FEATURE_UPDATE_INTERRUPT
  rtc: rv3032: let the core handle the alarm resolution
  rtc: s35390a: let the core handle the alarm resolution
  rtc: handle alarms with a minute resolution
  rtc: pcf85063: silence cppcheck warning
  rtc: rv8803: fix writing back ctrl in flag register
  rtc: s3c: Add time range
  rtc: s3c: Extract read/write IO into separate functions
  rtc: s3c: Remove usage of devm_rtc_device_register()
  rtc: tps80031: Remove driver
  rtc: sun6i: Allow probing without an early clock provider
  rtc: pcf8523: add BSM support
  ...

1 files changed, 13 insertions, 2 deletions

diff --git a/drivers/rtc/interface.c b/drivers/rtc/interface.c
index 9a2bd4947007..d8e835798153 100644
--- a/drivers/rtc/interface.c
+++ b/drivers/rtc/interface.c
@@ -423,6 +423,7 @@ static int __rtc_set_alarm(struct rtc_device *rtc, struct rtc_wkalrm *alarm)
 	if (err)
 		return err;
 	now = rtc_tm_to_time64(&tm);
+
 	if (scheduled <= now)
 		return -ETIME;
 	/*
@@ -447,6 +448,7 @@ static int __rtc_set_alarm(struct rtc_device *rtc, struct rtc_wkalrm *alarm)
 
 int rtc_set_alarm(struct rtc_device *rtc, struct rtc_wkalrm *alarm)
 {
+	ktime_t alarm_time;
 	int err;
 
 	if (!rtc->ops)
@@ -468,7 +470,15 @@ int rtc_set_alarm(struct rtc_device *rtc, struct rtc_wkalrm *alarm)
 	if (rtc->aie_timer.enabled)
 		rtc_timer_remove(rtc, &rtc->aie_timer);
 
-	rtc->aie_timer.node.expires = rtc_tm_to_ktime(alarm->time);
+	alarm_time = rtc_tm_to_ktime(alarm->time);
+	/*
+	 * Round down so we never miss a deadline, checking for past deadline is
+	 * done in __rtc_set_alarm
+	 */
+	if (test_bit(RTC_FEATURE_ALARM_RES_MINUTE, rtc->features))
+		alarm_time = ktime_sub_ns(alarm_time, (u64)alarm->time.tm_sec * NSEC_PER_SEC);
+
+	rtc->aie_timer.node.expires = alarm_time;
 	rtc->aie_timer.period = 0;
 	if (alarm->enabled)
 		err = rtc_timer_enqueue(rtc, &rtc->aie_timer);
@@ -561,7 +571,8 @@ int rtc_update_irq_enable(struct rtc_device *rtc, unsigned int enabled)
 	if (rtc->uie_rtctimer.enabled == enabled)
 		goto out;
 
-	if (rtc->uie_unsupported || !test_bit(RTC_FEATURE_ALARM, rtc->features)) {
+	if (!test_bit(RTC_FEATURE_UPDATE_INTERRUPT, rtc->features) ||
+	    !test_bit(RTC_FEATURE_ALARM, rtc->features)) {
 		mutex_unlock(&rtc->ops_lock);
 #ifdef CONFIG_RTC_INTF_DEV_UIE_EMUL
 		return rtc_dev_update_irq_enable_emul(rtc, enabled);