Hi Alexandre, On 25 October 2018 at 08:34, Alexandre Belloni <alexandre.belloni@xxxxxxxxxxx> wrote: > Hello, > > On 18/10/2018 16:52:30+0800, Baolin Wang wrote: >> When registering one RTC device, it will check to see if there is an >> alarm already set in RTC hardware by reading RTC alarm, at this time >> we should always read the normal alarm put in always-on region by >> checking the rtc->registered flag. >> >> Signed-off-by: Baolin Wang <baolin.wang@xxxxxxxxxx> >> --- >> drivers/rtc/rtc-sc27xx.c | 8 ++++++-- >> 1 file changed, 6 insertions(+), 2 deletions(-) >> >> diff --git a/drivers/rtc/rtc-sc27xx.c b/drivers/rtc/rtc-sc27xx.c >> index 72bb002..b4eb3b3 100644 >> --- a/drivers/rtc/rtc-sc27xx.c >> +++ b/drivers/rtc/rtc-sc27xx.c >> @@ -415,10 +415,14 @@ static int sprd_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm) >> u32 val; >> >> /* >> - * If aie_timer is enabled, we should get the normal alarm time. >> + * Before RTC device is registered, it will check to see if there is an >> + * alarm already set in RTC hardware, and we always read the normal >> + * alarm at this time. >> + * >> + * Or if aie_timer is enabled, we should get the normal alarm time. >> * Otherwise we should get auxiliary alarm time. >> */ >> - if (rtc->rtc && rtc->rtc->aie_timer.enabled == 0) >> + if (rtc->rtc && rtc->rtc->registered && rtc->rtc->aie_timer.enabled == 0) > > Note that the driver should not access rtc->registered and > rtc->aie_timer.enabled and this is a bit fragile. > But, on the other hand, I currently don't have anything better to > suggest. I was also planning to add an in-kernel API for multiple alarms > but I'm not sure it will actually help in your case. Yes, I understand your concern. I will glad to help to test if you introduce new APIs for multiple alarms to see if they can help in our case. Thanks. -- Baolin Wang Best Regards
