diff options
Diffstat (limited to 'nuttx/arch/arm/src/stm32/stm32_pmstandby.c')
-rw-r--r-- | nuttx/arch/arm/src/stm32/stm32_pmstandby.c | 109 |
1 files changed, 109 insertions, 0 deletions
diff --git a/nuttx/arch/arm/src/stm32/stm32_pmstandby.c b/nuttx/arch/arm/src/stm32/stm32_pmstandby.c new file mode 100644 index 000000000..467edaec2 --- /dev/null +++ b/nuttx/arch/arm/src/stm32/stm32_pmstandby.c @@ -0,0 +1,109 @@ +/**************************************************************************** + * arch/arm/src/stm32/stm32_pmstandby.c + * + * Copyright (C) 2012 Gregory Nutt. All rights reserved. + * Author: Gregory Nutt <gnutt@nuttx.org> + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in + * the documentation and/or other materials provided with the + * distribution. + * 3. Neither the name NuttX nor the names of its contributors may be + * used to endorse or promote products derived from this software + * without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS + * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE + * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, + * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, + * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS + * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED + * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN + * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE + * POSSIBILITY OF SUCH DAMAGE. + * + ****************************************************************************/ + +/**************************************************************************** + * Included Files + ****************************************************************************/ + +#include <nuttx/config.h> + +#include <stdbool.h> + +#include "up_arch.h" +#include "nvic.h" +#include "stm32_pwr.h" +#include "stm32_pm.h" + +/**************************************************************************** + * Pre-processor Definitions + ****************************************************************************/ + +/**************************************************************************** + * Private Data + ****************************************************************************/ + +/**************************************************************************** + * Private Functions + ****************************************************************************/ + +/**************************************************************************** + * Public Functions + ****************************************************************************/ + +/**************************************************************************** + * Name: stm32_pmstandby + * + * Description: + * Enter STANDBY mode. + * + * Input Parameters: + * None + * + * Returned Value. + * On success, this function will not return (STANDBY mode can only be + * terminated with a reset event). Otherwise, STANDBY mode did not occur + * and a negated errno value is returned to indicate the cause of the + * failure. + * + ****************************************************************************/ + +int stm32_pmstandby(void) +{ + uint32_t regval; + + /* Clear the Wake-Up Flag by setting the CWUF bit in the power control + * register. + */ + + regval = getreg32(STM32_PWR_CR); + regval |= PWR_CR_CWUF; + putreg32(regval, STM32_PWR_CR); + + /* Set the Power Down Deep Sleep (PDDS) bit in the power control register. */ + + regval |= PWR_CR_PDDS; + putreg32(regval, STM32_PWR_CR); + + /* Set SLEEPDEEP bit of Cortex System Control Register */ + + regval = getreg32(NVIC_SYSCON); + regval |= NVIC_SYSCON_SLEEPDEEP; + putreg32(regval, NVIC_SYSCON); + + /* Sleep until the wakeup reset occurs */ + + asm("wfi"); + return OK; /* Won't get here */ +} |