rtc: ab8500: let the core handle range

Let the core handle offsetting and windowing the RTC range.
The RTC has a 24 bit counter for minutes plus a seconds counter.
Keep the epoch at the beginning of 2000.

Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
This commit is contained in:
Alexandre Belloni 2018-09-24 16:49:01 +02:00
parent b56295dd33
commit 38ab97aebe

View File

@ -46,7 +46,6 @@
#define RTC_STATUS_DATA 0x01
#define COUNTS_PER_SEC (0xF000 / 60)
#define AB8500_RTC_EPOCH 2000
static const u8 ab8500_rtc_time_regs[] = {
AB8500_RTC_WATCH_TMIN_HI_REG, AB8500_RTC_WATCH_TMIN_MID_REG,
@ -59,23 +58,6 @@ static const u8 ab8500_rtc_alarm_regs[] = {
AB8500_RTC_ALRM_MIN_LOW_REG
};
/* Calculate the seconds from 1970 to 01-01-2000 00:00:00 */
static unsigned long get_elapsed_seconds(int year)
{
unsigned long secs;
struct rtc_time tm = {
.tm_year = year - 1900,
.tm_mday = 1,
};
/*
* This function calculates secs from 1970 and not from
* 1900, even if we supply the offset from year 1900.
*/
rtc_tm_to_time(&tm, &secs);
return secs;
}
static int ab8500_rtc_read_time(struct device *dev, struct rtc_time *tm)
{
unsigned long timeout = jiffies + HZ;
@ -118,9 +100,6 @@ static int ab8500_rtc_read_time(struct device *dev, struct rtc_time *tm)
secs = secs / COUNTS_PER_SEC;
secs = secs + (mins * 60);
/* Add back the initially subtracted number of seconds */
secs += get_elapsed_seconds(AB8500_RTC_EPOCH);
rtc_time_to_tm(secs, tm);
return 0;
}
@ -131,21 +110,8 @@ static int ab8500_rtc_set_time(struct device *dev, struct rtc_time *tm)
unsigned char buf[ARRAY_SIZE(ab8500_rtc_time_regs)];
unsigned long no_secs, no_mins, secs = 0;
if (tm->tm_year < (AB8500_RTC_EPOCH - 1900)) {
dev_dbg(dev, "year should be equal to or greater than %d\n",
AB8500_RTC_EPOCH);
return -EINVAL;
}
/* Get the number of seconds since 1970 */
rtc_tm_to_time(tm, &secs);
/*
* Convert it to the number of seconds since 01-01-2000 00:00:00, since
* we only have a small counter in the RTC.
*/
secs -= get_elapsed_seconds(AB8500_RTC_EPOCH);
no_mins = secs / 60;
no_secs = secs % 60;
@ -202,9 +168,6 @@ static int ab8500_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alarm)
mins = (buf[0] << 16) | (buf[1] << 8) | (buf[2]);
secs = mins * 60;
/* Add back the initially subtracted number of seconds */
secs += get_elapsed_seconds(AB8500_RTC_EPOCH);
rtc_time_to_tm(secs, &alarm->time);
return rtc_valid_tm(&alarm->time);
@ -224,12 +187,6 @@ static int ab8500_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alarm)
unsigned long mins, secs = 0, cursec = 0;
struct rtc_time curtm;
if (alarm->time.tm_year < (AB8500_RTC_EPOCH - 1900)) {
dev_dbg(dev, "year should be equal to or greater than %d\n",
AB8500_RTC_EPOCH);
return -EINVAL;
}
/* Get the number of seconds since 1970 */
rtc_tm_to_time(&alarm->time, &secs);
@ -245,12 +202,6 @@ static int ab8500_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alarm)
return -EINVAL;
}
/*
* Convert it to the number of seconds since 01-01-2000 00:00:00, since
* we only have a small counter in the RTC.
*/
secs -= get_elapsed_seconds(AB8500_RTC_EPOCH);
mins = secs / 60;
buf[2] = mins & 0xFF;
@ -445,6 +396,10 @@ static int ab8500_rtc_probe(struct platform_device *pdev)
rtc->uie_unsupported = 1;
rtc->range_max = (1ULL << 24) * 60 - 1; // 24-bit minutes + 59 secs
rtc->start_secs = RTC_TIMESTAMP_BEGIN_2000;
rtc->set_start_time = true;
err = rtc_add_group(rtc, &ab8500_rtc_sysfs_files);
if (err)
return err;