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stm32/powerctrl: Disable RTC write protection before changing flags.

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iabdalkader 2020-12-02 23:35:58 +02:00 committed by Damien George
parent 463a275bc4
commit 8add94e94e
1 changed files with 7 additions and 0 deletions
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7
ports/stm32/powerctrl.c
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@ -689,6 +689,10 @@ void powerctrl_enter_standby_mode(void) {
// save RTC interrupts // save RTC interrupts
uint32_t save_irq_bits = RTC->CR & CR_BITS; uint32_t save_irq_bits = RTC->CR & CR_BITS;
// disable register write protection
RTC->WPR = 0xca;
RTC->WPR = 0x53;
// disable RTC interrupts // disable RTC interrupts
RTC->CR &= ~CR_BITS; RTC->CR &= ~CR_BITS;
@ -714,6 +718,9 @@ void powerctrl_enter_standby_mode(void) {
// enable previously-enabled RTC interrupts // enable previously-enabled RTC interrupts
RTC->CR |= save_irq_bits; RTC->CR |= save_irq_bits;
// enable register write protection
RTC->WPR = 0xff;
#if defined(STM32F7) #if defined(STM32F7)
// Enable the internal (eg RTC) wakeup sources // Enable the internal (eg RTC) wakeup sources
// See Errata 2.2.2 "Wakeup from Standby mode when the back-up SRAM regulator is enabled" // See Errata 2.2.2 "Wakeup from Standby mode when the back-up SRAM regulator is enabled"