diff options
Diffstat (limited to 'include/linux/rtc.h')
| -rw-r--r-- | include/linux/rtc.h | 109 |
1 files changed, 56 insertions, 53 deletions
diff --git a/include/linux/rtc.h b/include/linux/rtc.h index 22d1575e4991..95da051fb155 100644 --- a/include/linux/rtc.h +++ b/include/linux/rtc.h @@ -42,7 +42,7 @@ static inline time64_t rtc_tm_sub(struct rtc_time *lhs, struct rtc_time *rhs) #include <linux/timerqueue.h> #include <linux/workqueue.h> -extern struct class *rtc_class; +extern const struct class rtc_class; /* * For these RTC methods the device parameter is the physical device @@ -66,6 +66,8 @@ struct rtc_class_ops { int (*alarm_irq_enable)(struct device *, unsigned int enabled); int (*read_offset)(struct device *, long *offset); int (*set_offset)(struct device *, long offset); + int (*param_get)(struct device *, struct rtc_param *param); + int (*param_set)(struct device *, struct rtc_param *param); }; struct rtc_device; @@ -80,6 +82,7 @@ struct rtc_timer { /* flags */ #define RTC_DEV_BUSY 0 +#define RTC_NO_CDEV 1 struct rtc_device { struct device dev; @@ -107,25 +110,43 @@ struct rtc_device { struct hrtimer pie_timer; /* sub second exp, so needs hrtimer */ int pie_enabled; struct work_struct irqwork; - /* Some hardware can't support UIE mode */ - int uie_unsupported; - - /* Number of nsec it takes to set the RTC clock. This influences when - * the set ops are called. An offset: - * - of 0.5 s will call RTC set for wall clock time 10.0 s at 9.5 s - * - of 1.5 s will call RTC set for wall clock time 10.0 s at 8.5 s - * - of -0.5 s will call RTC set for wall clock time 10.0 s at 10.5 s - */ - long set_offset_nsec; - bool registered; + /* + * This offset specifies the update timing of the RTC. + * + * tsched t1 write(t2.tv_sec - 1sec)) t2 RTC increments seconds + * + * The offset defines how tsched is computed so that the write to + * the RTC (t2.tv_sec - 1sec) is correct versus the time required + * for the transport of the write and the time which the RTC needs + * to increment seconds the first time after the write (t2). + * + * For direct accessible RTCs tsched ~= t1 because the write time + * is negligible. For RTCs behind slow busses the transport time is + * significant and has to be taken into account. + * + * The time between the write (t1) and the first increment after + * the write (t2) is RTC specific. For a MC146818 RTC it's 500ms, + * for many others it's exactly 1 second. Consult the datasheet. + * + * The value of this offset is also used to calculate the to be + * written value (t2.tv_sec - 1sec) at tsched. + * + * The default value for this is NSEC_PER_SEC + 10 msec default + * transport time. The offset can be adjusted by drivers so the + * calculation for the to be written value at tsched becomes + * correct: + * + * newval = tsched + set_offset_nsec - NSEC_PER_SEC + * and (tsched + set_offset_nsec) % NSEC_PER_SEC == 0 + */ + unsigned long set_offset_nsec; - /* Old ABI support */ - bool nvram_old_abi; - struct bin_attribute *nvram; + unsigned long features[BITS_TO_LONGS(RTC_FEATURE_CNT)]; time64_t range_min; timeu64_t range_max; + timeu64_t alarm_offset_max; time64_t start_secs; time64_t offset_secs; bool set_start_time; @@ -149,6 +170,7 @@ struct rtc_device { /* useful timestamps */ #define RTC_TIMESTAMP_BEGIN_0000 -62167219200ULL /* 0000-01-01 00:00:00 */ #define RTC_TIMESTAMP_BEGIN_1900 -2208988800LL /* 1900-01-01 00:00:00 */ +#define RTC_TIMESTAMP_EPOCH_GPS 315964800LL /* 1980-01-06 00:00:00 */ #define RTC_TIMESTAMP_BEGIN_2000 946684800LL /* 2000-01-01 00:00:00 */ #define RTC_TIMESTAMP_END_2063 2966371199LL /* 2063-12-31 23:59:59 */ #define RTC_TIMESTAMP_END_2079 3471292799LL /* 2079-12-31 23:59:59 */ @@ -161,11 +183,10 @@ extern struct rtc_device *devm_rtc_device_register(struct device *dev, const struct rtc_class_ops *ops, struct module *owner); struct rtc_device *devm_rtc_allocate_device(struct device *dev); -int __rtc_register_device(struct module *owner, struct rtc_device *rtc); +int __devm_rtc_register_device(struct module *owner, struct rtc_device *rtc); extern int rtc_read_time(struct rtc_device *rtc, struct rtc_time *tm); extern int rtc_set_time(struct rtc_device *rtc, struct rtc_time *tm); -extern int rtc_set_ntp_time(struct timespec64 now, unsigned long *target_nsec); int __rtc_read_alarm(struct rtc_device *rtc, struct rtc_wkalrm *alarm); extern int rtc_read_alarm(struct rtc_device *rtc, struct rtc_wkalrm *alrm); @@ -205,41 +226,25 @@ static inline bool is_leap_year(unsigned int year) return (!(year % 4) && (year % 100)) || !(year % 400); } -/* Determine if we can call to driver to set the time. Drivers can only be - * called to set a second aligned time value, and the field set_offset_nsec - * specifies how far away from the second aligned time to call the driver. - * - * This also computes 'to_set' which is the time we are trying to set, and has - * a zero in tv_nsecs, such that: - * to_set - set_delay_nsec == now +/- FUZZ +/** + * rtc_bound_alarmtime() - Return alarm time bound by rtc limit + * @rtc: Pointer to rtc device structure + * @requested: Requested alarm timeout * + * Return: Alarm timeout bound by maximum alarm time supported by rtc. */ -static inline bool rtc_tv_nsec_ok(s64 set_offset_nsec, - struct timespec64 *to_set, - const struct timespec64 *now) +static inline ktime_t rtc_bound_alarmtime(struct rtc_device *rtc, + ktime_t requested) { - /* Allowed error in tv_nsec, arbitarily set to 5 jiffies in ns. */ - const unsigned long TIME_SET_NSEC_FUZZ = TICK_NSEC * 5; - struct timespec64 delay = {.tv_sec = 0, - .tv_nsec = set_offset_nsec}; - - *to_set = timespec64_add(*now, delay); - - if (to_set->tv_nsec < TIME_SET_NSEC_FUZZ) { - to_set->tv_nsec = 0; - return true; - } - - if (to_set->tv_nsec > NSEC_PER_SEC - TIME_SET_NSEC_FUZZ) { - to_set->tv_sec++; - to_set->tv_nsec = 0; - return true; - } - return false; + if (rtc->alarm_offset_max && + rtc->alarm_offset_max * MSEC_PER_SEC < ktime_to_ms(requested)) + return ms_to_ktime(rtc->alarm_offset_max * MSEC_PER_SEC); + + return requested; } -#define rtc_register_device(device) \ - __rtc_register_device(THIS_MODULE, device) +#define devm_rtc_register_device(device) \ + __devm_rtc_register_device(THIS_MODULE, device) #ifdef CONFIG_RTC_HCTOSYS_DEVICE extern int rtc_hctosys_ret; @@ -248,16 +253,14 @@ extern int rtc_hctosys_ret; #endif #ifdef CONFIG_RTC_NVMEM -int rtc_nvmem_register(struct rtc_device *rtc, - struct nvmem_config *nvmem_config); -void rtc_nvmem_unregister(struct rtc_device *rtc); +int devm_rtc_nvmem_register(struct rtc_device *rtc, + struct nvmem_config *nvmem_config); #else -static inline int rtc_nvmem_register(struct rtc_device *rtc, - struct nvmem_config *nvmem_config) +static inline int devm_rtc_nvmem_register(struct rtc_device *rtc, + struct nvmem_config *nvmem_config) { return 0; } -static inline void rtc_nvmem_unregister(struct rtc_device *rtc) {} #endif #ifdef CONFIG_RTC_INTF_SYSFS |