[PATCH] rtc: cros-ec: return -ETIME when refused to set alarms in the past

[Jeffy Chen]

We have a check in __rtc_set_alarm() to return -ETIME when the alarm
is in the past.

Since accessing a Chrome OS EC based rtc is a slow operation, we should
do that check again inside of the EC rtc driver's .set_alarm() callback.

Signed-off-by: Jeffy Chen <jeffy.c...@rock-chips.com>
---

 drivers/rtc/rtc-cros-ec.c | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/drivers/rtc/rtc-cros-ec.c b/drivers/rtc/rtc-cros-ec.c
index f0ea6899c731..ee0062e2d222 100644
--- a/drivers/rtc/rtc-cros-ec.c
+++ b/drivers/rtc/rtc-cros-ec.c
@@ -188,6 +188,10 @@ static int cros_ec_rtc_set_alarm(struct device *dev, 
struct rtc_wkalrm *alrm)
        if (alarm_time < 0 || alarm_time > U32_MAX)
                return -EINVAL;
 
+       /* Don't set an alarm in the past. */
+       if ((u32)alarm_time <= current_time)
+               return -ETIME;
+
        if (!alrm->enabled) {
                /*
                 * If the alarm is being disabled, send an alarm
@@ -196,11 +200,7 @@ static int cros_ec_rtc_set_alarm(struct device *dev, 
struct rtc_wkalrm *alrm)
                alarm_offset = EC_RTC_ALARM_CLEAR;
                cros_ec_rtc->saved_alarm = (u32)alarm_time;
        } else {
-               /* Don't set an alarm in the past. */
-               if ((u32)alarm_time < current_time)
-                       alarm_offset = EC_RTC_ALARM_CLEAR;
-               else
-                       alarm_offset = (u32)alarm_time - current_time;
+               alarm_offset = (u32)alarm_time - current_time;
        }
 
        ret = cros_ec_rtc_set(cros_ec, EC_CMD_RTC_SET_ALARM, alarm_offset);
-- 
2.11.0