Re: [PATCH v8 05/11] rtc: sun6i: Add support for broken-down alarm registers
From: Jernej Škrabec <jernej.skrabec@gmail.com>
Date: 2021-07-25 06:11:56
Also in:
linux-rtc, linux-sunxi, lkml
Hi Andre! Dne petek, 23. julij 2021 ob 17:38:32 CEST je Andre Przywara napisal(a):
quoted hunk ↗ jump to hunk
Newer versions of the Allwinner RTC, for instance as found in the H616 SoC, not only store the current day as a linear number, but also change the way the alarm is handled: There are now two registers, that explicitly store the wakeup time, in the same format as the current time. Add support for that variant by writing the requested wakeup time directly into the registers, instead of programming the seconds left, as the old SoCs required. Signed-off-by: Andre Przywara <andre.przywara@arm.com> --- drivers/rtc/rtc-sun6i.c | 60 +++++++++++++++++++++++++++++------------ 1 file changed, 43 insertions(+), 17 deletions(-)diff --git a/drivers/rtc/rtc-sun6i.c b/drivers/rtc/rtc-sun6i.c index a02be8bca6f3..f0ee20bfdccb 100644 --- a/drivers/rtc/rtc-sun6i.c +++ b/drivers/rtc/rtc-sun6i.c@@ -48,7 +48,8 @@ /* Alarm 0 (counter) */ #define SUN6I_ALRM_COUNTER 0x0020 -#define SUN6I_ALRM_CUR_VAL 0x0024 +/* This holds the remaining alarm seconds on older SoCs (current value) */ +#define SUN6I_ALRM_COUNTER_HMS 0x0024 #define SUN6I_ALRM_EN 0x0028 #define SUN6I_ALRM_EN_CNT_EN BIT(0) #define SUN6I_ALRM_IRQ_EN 0x002c@@ -523,32 +524,57 @@ static int sun6i_rtc_setalarm(struct device *dev,
struct rtc_wkalrm *wkalrm)
struct sun6i_rtc_dev *chip = dev_get_drvdata(dev);
struct rtc_time *alrm_tm = &wkalrm->time;
struct rtc_time tm_now;
- time64_t time_now, time_set;
+ time64_t time_set;
+ u32 counter_val, counter_val_hms;
int ret;
- ret = sun6i_rtc_gettime(dev, &tm_now);
- if (ret < 0) {
- dev_err(dev, "Error in getting time\n");
- return -EINVAL;
- }
-
time_set = rtc_tm_to_time64(alrm_tm);
- time_now = rtc_tm_to_time64(&tm_now);
- if (time_set <= time_now) {
- dev_err(dev, "Date to set in the past\n");
- return -EINVAL;
- }
- if ((time_set - time_now) > U32_MAX) {
- dev_err(dev, "Date too far in the future\n");
- return -EINVAL;
+ if (chip->flags & RTC_LINEAR_DAY) {
+ time64_t seconds;
+
+ /*
+ * The alarm registers hold the actual alarm time, encoded
+ * in the same way (linear day + HMS) as the current
time.
+ */ + counter_val_hms = SUN6I_TIME_SET_SEC_VALUE(alrm_tm- tm_sec) | +
SUN6I_TIME_SET_MIN_VALUE(alrm_tm->tm_min) |
+
SUN6I_TIME_SET_HOUR_VALUE(alrm_tm->tm_hour);
+ seconds = mktime64(alrm_tm->tm_year + 1900, alrm_tm- tm_mon, + alrm_tm->tm_mday, 0, 0, 0);
While above line should work, it's confusing why you're adding 1900 to years. In my opinion it would be better to use same trick you used in patch 4 - rtc_tm_to_time64() with hours, minutes and seconds set to 0. Or maybe you don't even need to do that, since division by SECS_PER_DAY will round down anyway. In such way you hide RTC internal representation detail which doesn't need to be exposed here. Once fixed: Reviewed by: Jernej Skrabec [off-list ref] Best regards, Jernej
+ counter_val = div_u64(seconds, SECS_PER_DAY);
+ } else {
+ /* The alarm register holds the number of seconds left. */
+ time64_t time_now;
+
+ ret = sun6i_rtc_gettime(dev, &tm_now);
+ if (ret < 0) {
+ dev_err(dev, "Error in getting time\n");
+ return -EINVAL;
+ }
+
+ time_now = rtc_tm_to_time64(&tm_now);
+ if (time_set <= time_now) {
+ dev_err(dev, "Date to set in the past\n");
+ return -EINVAL;
+ }
+ if ((time_set - time_now) > U32_MAX) {
+ dev_err(dev, "Date too far in the future\n");
+ return -EINVAL;
+ }
+
+ counter_val = time_set - time_now;
}
sun6i_rtc_setaie(0, chip);
writel(0, chip->base + SUN6I_ALRM_COUNTER);
+ if (chip->flags & RTC_LINEAR_DAY)
+ writel(0, chip->base + SUN6I_ALRM_COUNTER_HMS);
usleep_range(100, 300);
- writel(time_set - time_now, chip->base + SUN6I_ALRM_COUNTER);
+ writel(counter_val, chip->base + SUN6I_ALRM_COUNTER);
+ if (chip->flags & RTC_LINEAR_DAY)
+ writel(counter_val_hms, chip->base + SUN6I_ALRM_COUNTER_HMS);
chip->alarm = time_set; sun6i_rtc_setaie(wkalrm->enabled, chip); -- 2.17.6
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