rtc: ab8500: let the core handle the alarm resolution

Tell the RTC core UIE are not supported because the resolution of the alarm
is a minute.

Note that this is in fact also fixing how the resolution is reported as the
previous test was simply ensuring the alarm was more than a minute in the
future while the register has a minute resolution.
This would be ok if the alarm was a countdown but ab8500_rtc_read_alarm
suggests otherwise and the AB8500 datasheet states that the RTC
documentation is not public.

Finally, the comment is wrong and what makes the UIE emulation work is
uie_unsupported being set.

Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20211107225458.111068-6-alexandre.belloni@bootlin.com
This commit is contained in:
Alexandre Belloni 2021-11-07 23:54:51 +01:00
parent 27f06af753
commit a5f828036c

View File

@ -184,25 +184,9 @@ static int ab8500_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alarm)
{
int retval, i;
unsigned char buf[ARRAY_SIZE(ab8500_rtc_alarm_regs)];
unsigned long mins, secs = 0, cursec = 0;
struct rtc_time curtm;
unsigned long mins;
/* Get the number of seconds since 1970 */
secs = rtc_tm_to_time64(&alarm->time);
/*
* Check whether alarm is set less than 1min.
* Since our RTC doesn't support alarm resolution less than 1min,
* return -EINVAL, so UIE EMUL can take it up, incase of UIE_ON
*/
ab8500_rtc_read_time(dev, &curtm); /* Read current time */
cursec = rtc_tm_to_time64(&curtm);
if ((secs - cursec) < 59) {
dev_dbg(dev, "Alarm less than 1 minute not supported\r\n");
return -EINVAL;
}
mins = secs / 60;
mins = (unsigned long)rtc_tm_to_time64(&alarm->time) / 60;
buf[2] = mins & 0xFF;
buf[1] = (mins >> 8) & 0xFF;
@ -394,7 +378,8 @@ static int ab8500_rtc_probe(struct platform_device *pdev)
dev_pm_set_wake_irq(&pdev->dev, irq);
platform_set_drvdata(pdev, rtc);
rtc->uie_unsupported = 1;
set_bit(RTC_FEATURE_ALARM_RES_MINUTE, rtc->features);
clear_bit(RTC_FEATURE_UPDATE_INTERRUPT, rtc->features);
rtc->range_max = (1ULL << 24) * 60 - 1; // 24-bit minutes + 59 secs
rtc->start_secs = RTC_TIMESTAMP_BEGIN_2000;