Stm32 rtc small patches
* RTC: canceling an alarm marks it as inactive
* STM32L4, STM32F4, STM32F7 RTC: fix reading alarm value that is more than 24h in future
* STM32F0 RTC: fix backup register count in stm32_rtcc.h
All other STM32: SHIFTR_SUBFS_MASK was correct in STM32F0 only
* STM32L1: use correct EXTI line definitions
Approved-by: Gregory Nutt <gnutt@nuttx.org>
STM32L4 small fixes to RTC
* STM32L4 RTC: init mode was never exited because nested locking in rtc_synchwait() disabled backup domain access
* STM32L4 RTC: use backup register magic value instead of INITS bit
The INITS (bit 4) of RTC_ISR register cannot be used to reliably
detect backup domain reset. This is because we can operate our
device without ever initializing the year field in the RTC calendar
if our application does not care about correct date being set.
Hardware also clears the bit when RTC date is set back to year 2000:
nsh> date -s "Jan 01 00:00:00 2001"
rtc_dumptime: Setting time:
rtc_dumptime: tm: 2001-01-01 00:00:00
rtc_dumpregs: New time setting:
rtc_dumpregs: TR: 00000000
rtc_dumpregs: DR: 00012101
rtc_dumpregs: CR: 00000000
rtc_dumpregs: ISR: 00000037
...
nsh> date -s "Jan 01 00:00:00 2000"
rtc_dumptime: Setting time:
rtc_dumptime: tm: 2000-01-01 00:00:00
rtc_dumpregs: New time setting:
rtc_dumpregs: TR: 00000000
rtc_dumpregs: DR: 0000c101
rtc_dumpregs: CR: 00000000
rtc_dumpregs: ISR: 00000027 <--- Bit 4 went missing!
...
This patch allows us to do:
stm32l4_pmstop(true);
/* Stop mode disables HSE/HSI/PLL and wake happens with default system
* clock. So reconfigure clocks early on Stop mode return.
*/
stm32l4_clockconfig();
without stm32l4_clockconfig() doing spurious and harmful backup domain
reset in rcc_resetbkp().
* STM32L4 RTC: put back the SSR race condition workaround
ST has confirmed that the issue has not been fixed, and that it applies
to STM32L4 too (was not in errata sheets due to documentation bug)
See discussion:
https://community.st.com/thread/43710-issue-with-rtc-maximum-time-resolution
* STM32F4, STM32L4, STM32F7 RTC: add more CONFIG_RTC_NALARMS > 1 to reduce code size
* STM32L4: rename stm32l4_rtcc.c to stm32l4_rtc.c to better match STM32F7
Cosmetic changes to comments
* STM32, STM32L4, STM32F7 RTC: stray comment and typos in chip/stm32_rtcc.h
* STM32L4 RTC: change maximum alarm time from 24h to one month
Approved-by: Gregory Nutt <gnutt@nuttx.org>
Add clock_resynchronize for better synchronization of CLOCK_REALTIME and CLOCK_MONOTONIC to match RTC after resume from low-power state.
Add up_rtc_getdatetime_with_subseconds under CONFIG_ARCH_HAVE_RTC_SUBSECONDS to allow initializing (and resynchronizing) system clock with subseconds accuracy RTC.
New interface allows checking if RTC time has been set. This allows to application to detect if RTC has valid time (after
reset) or should application attempt to get real time by other means (for example, by launching ntpclient or GPS).
Remove proxy #defines
Ensure the LSE(ON) etal are set and remembered in
a) A cold start (RTC_MAGIC invalid) of the RTC
b) A warm start (RTC_MAGIC valid) of the RTC but a clock change.
The change was needed because in bench testing a merge of the latest's STM32 53ec3ca (and friends) it became apparent that the
Sequence of operation is wrong in the reset of the Backup Domain in the RCC code. PWR is required before the Backup Domain
can be futzed with. !!!This Code should be tested on STM32 and if needed rippled to the STM32 families
