Commit a5f82803 authored by Alexandre Belloni's avatar Alexandre Belloni
Browse files

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: default avatarAlexandre Belloni <alexandre.belloni@bootlin.com>
Acked-by: default avatarLinus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20211107225458.111068-6-alexandre.belloni@bootlin.com
parent 27f06af7

drivers/rtc/rtc-ab8500.c

+4 −19
Original line number Diff line number Diff line
@@ -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;