FreeRTOS/Demo/CORTEX_MPU_M3_NUCLEO_L152RE_GCC/ST_Code/Drivers/STM32L1xx_HAL_Driver/Src/stm32l1xx_hal_gpio.c

/**
  ******************************************************************************
  * @file    stm32l1xx_hal_gpio.c
  * @author  MCD Application Team
  * @brief   GPIO HAL module driver.
  *          This file provides firmware functions to manage the following 
  *          functionalities of the General Purpose Input/Output (GPIO) peripheral:
  *           + Initialization and de-initialization functions
  *           + IO operation functions
  *         
  @verbatim
  ==============================================================================
                    ##### GPIO Peripheral features #####
  ==============================================================================         
  [..] 
  Each port bit of the general-purpose I/O (GPIO) ports can be individually 
  configured by software in several modes:
  (+) Input mode 
  (+) Analog mode
  (+) Output mode
  (+) Alternate function mode
  (+) External interrupt/event lines
 
  [..]  
  During and just after reset, the alternate functions and external interrupt  
  lines are not active and the I/O ports are configured in input floating mode.
  
  [..]   
  All GPIO pins have weak internal pull-up and pull-down resistors, which can be 
  activated or not.

  [..]
  In Output or Alternate mode, each IO can be configured on open-drain or push-pull
  type and the IO speed can be selected depending on the VDD value.
  
  [..]
  The microcontroller IO pins are connected to onboard peripherals/modules through a 
  multiplexer that allows only one peripheral s alternate function (AF) connected 
  to an IO pin at a time. In this way, there can be no conflict between peripherals 
  sharing the same IO pin. 
  
  [..]  
  All ports have external interrupt/event capability. To use external interrupt 
  lines, the port must be configured in input mode. All available GPIO pins are 
  connected to the 16 external interrupt/event lines from EXTI0 to EXTI15.
  
  [..]  
  The external interrupt/event controller consists of up to 28 edge detectors 
  (depending on products 16 lines are connected to GPIO) for generating event/interrupt
  requests (each input line can be independently configured to select the type 
  (interrupt or event) and the corresponding trigger event (rising or falling or both). 
  Each line can also be masked independently. 
   
            ##### How to use this driver #####
  ==============================================================================  
  [..]
   (#) Enable the GPIO AHB clock using the following function : __GPIOx_CLK_ENABLE(). 
                                    
   (#) Configure the GPIO pin(s) using HAL_GPIO_Init().
       (++) Configure the IO mode using "Mode" member from GPIO_InitTypeDef structure
       (++) Activate Pull-up, Pull-down resistor using "Pull" member from GPIO_InitTypeDef 
            structure.
       (++) In case of Output or alternate function mode selection: the speed is 
            configured through "Speed" member from GPIO_InitTypeDef structure, 
            the speed is configurable: Low, Medium and High.
       (++) If alternate mode is selected, the alternate function connected to the IO
            is configured through "Alternate" member from GPIO_InitTypeDef structure
       (++) Analog mode is required when a pin is to be used as ADC channel 
            or DAC output.
       (++) In case of external interrupt/event selection the "Mode" member from 
            GPIO_InitTypeDef structure select the type (interrupt or event) and 
            the corresponding trigger event (rising or falling or both).
  
   (#) In case of external interrupt/event mode selection, configure NVIC IRQ priority 
       mapped to the EXTI line using HAL_NVIC_SetPriority() and enable it using
       HAL_NVIC_EnableIRQ().
  
   (#) HAL_GPIO_DeInit allows to set register values to their reset value. It's also 
       recommended to use it to unconfigure pin which was used as an external interrupt 
       or in event mode. That's the only way to reset corresponding bit in EXTI & SYSCFG 
       registers.
  
   (#) To get the level of a pin configured in input mode use HAL_GPIO_ReadPin().
  
   (#) To set/reset the level of a pin configured in output mode use 
       HAL_GPIO_WritePin()/HAL_GPIO_TogglePin().
  
   (#) To lock pin configuration until next reset use HAL_GPIO_LockPin().
  
   (#) During and just after reset, the alternate functions are not 
       active and the GPIO pins are configured in input floating mode (except JTAG
       pins).
  
   (#) The LSE oscillator pins OSC32_IN and OSC32_OUT can be used as general purpose 
       (PC14 and PC15, respectively) when the LSE oscillator is off. The LSE has 
       priority over the GPIO function.
  
   (#) The HSE oscillator pins OSC_IN/OSC_OUT can be used as 
       general purpose PH0 and PH1, respectively, when the HSE oscillator is off. 
       The HSE has priority over the GPIO function.
  
  @endverbatim
  ******************************************************************************
  * @attention
  *
  * <h2><center>&copy; Copyright (c) 2017 STMicroelectronics.
  * All rights reserved.</center></h2>
  *
  * This software component is licensed by ST under BSD 3-Clause license,
  * the "License"; You may not use this file except in compliance with the
  * License. You may obtain a copy of the License at:
  *                        opensource.org/licenses/BSD-3-Clause
  *
  ******************************************************************************  
  */

/* Includes ------------------------------------------------------------------*/
#include "stm32l1xx_hal.h"

/** @addtogroup STM32L1xx_HAL_Driver
  * @{
  */

/** @addtogroup GPIO
  * @brief GPIO HAL module driver
  * @{
  */

#ifdef HAL_GPIO_MODULE_ENABLED

/* Private typedef -----------------------------------------------------------*/
/* Private define ------------------------------------------------------------*/
/** @addtogroup GPIO_Private_Constants
  * @{
  */
#define GPIO_MODE             (0x00000003U)
#define EXTI_MODE             (0x10000000U)
#define GPIO_MODE_IT          (0x00010000U)
#define GPIO_MODE_EVT         (0x00020000U)
#define RISING_EDGE           (0x00100000U)
#define FALLING_EDGE          (0x00200000U)
#define GPIO_OUTPUT_TYPE      (0x00000010U)

#define GPIO_NUMBER           (16U)
 
/**
  * @}
  */
  
/* Private macro -------------------------------------------------------------*/
/* Private variables ---------------------------------------------------------*/
/* Private function prototypes -----------------------------------------------*/
/* Exported functions ---------------------------------------------------------*/

/** @addtogroup GPIO_Exported_Functions
  * @{
  */

/** @addtogroup GPIO_Exported_Functions_Group1
 *  @brief    Initialization and Configuration functions 
 *
@verbatim    
 ===============================================================================
              ##### Initialization and Configuration functions #####
 ===============================================================================
 
@endverbatim
  * @{
  */

/**
  * @brief  Initializes the GPIOx peripheral according to the specified parameters in the GPIO_Init.
  * @param  GPIOx where x can be (A..G depending on device used) to select the GPIO peripheral for STM32L1XX family devices
  * @param  GPIO_Init pointer to a GPIO_InitTypeDef structure that contains
  *         the configuration information for the specified GPIO peripheral.
  * @retval None
  */
void HAL_GPIO_Init(GPIO_TypeDef  *GPIOx, GPIO_InitTypeDef *GPIO_Init)
{ 
  uint32_t position = 0x00;
  uint32_t iocurrent = 0x00;
  uint32_t temp = 0x00;

  /* Check the parameters */
  assert_param(IS_GPIO_ALL_INSTANCE(GPIOx));
  assert_param(IS_GPIO_PIN(GPIO_Init->Pin));
  assert_param(IS_GPIO_MODE(GPIO_Init->Mode));
  assert_param(IS_GPIO_PULL(GPIO_Init->Pull)); 

  /* Configure the port pins */
  while (((GPIO_Init->Pin) >> position) != 0)
  {
    /* Get current io position */
    iocurrent = (GPIO_Init->Pin) & (1U << position);
    
    if(iocurrent)
    {
      /*--------------------- GPIO Mode Configuration ------------------------*/
      /* In case of Alternate function mode selection */
      if((GPIO_Init->Mode == GPIO_MODE_AF_PP) || (GPIO_Init->Mode == GPIO_MODE_AF_OD)) 
      {
        /* Check the Alternate function parameters */
        assert_param(IS_GPIO_AF_INSTANCE(GPIOx));
        assert_param(IS_GPIO_AF(GPIO_Init->Alternate));
        
        /* Configure Alternate function mapped with the current IO */ 
        /* Identify AFRL or AFRH register based on IO position*/
        temp = GPIOx->AFR[position >> 3];
        CLEAR_BIT(temp, 0xFU << ((uint32_t)(position & 0x07U) * 4)) ;      
        SET_BIT(temp, (uint32_t)(GPIO_Init->Alternate) << (((uint32_t)position & 0x07U) * 4));       
        GPIOx->AFR[position >> 3] = temp;
      }

      /* Configure IO Direction mode (Input, Output, Alternate or Analog) */
      temp = GPIOx->MODER;
      CLEAR_BIT(temp, GPIO_MODER_MODER0 << (position * 2));   
      SET_BIT(temp, (GPIO_Init->Mode & GPIO_MODE) << (position * 2));
      GPIOx->MODER = temp;

      /* In case of Output or Alternate function mode selection */
      if ((GPIO_Init->Mode == GPIO_MODE_OUTPUT_PP) || (GPIO_Init->Mode == GPIO_MODE_AF_PP) ||
          (GPIO_Init->Mode == GPIO_MODE_OUTPUT_OD) || (GPIO_Init->Mode == GPIO_MODE_AF_OD))
      {
        /* Check the Speed parameter */
        assert_param(IS_GPIO_SPEED(GPIO_Init->Speed));
        /* Configure the IO Speed */
        temp = GPIOx->OSPEEDR; 
        CLEAR_BIT(temp, GPIO_OSPEEDER_OSPEEDR0 << (position * 2));
        SET_BIT(temp, GPIO_Init->Speed << (position * 2));
        GPIOx->OSPEEDR = temp;

        /* Configure the IO Output Type */
        temp = GPIOx->OTYPER;
        CLEAR_BIT(temp, GPIO_OTYPER_OT_0 << position) ;
        SET_BIT(temp, ((GPIO_Init->Mode & GPIO_OUTPUT_TYPE) >> 4) << position);
        GPIOx->OTYPER = temp;
      }

      /* Activate the Pull-up or Pull down resistor for the current IO */
      temp = GPIOx->PUPDR;
      CLEAR_BIT(temp, GPIO_PUPDR_PUPDR0 << (position * 2));
      SET_BIT(temp, (GPIO_Init->Pull) << (position * 2));
      GPIOx->PUPDR = temp;

      /*--------------------- EXTI Mode Configuration ------------------------*/
      /* Configure the External Interrupt or event for the current IO */
      if((GPIO_Init->Mode & EXTI_MODE) == EXTI_MODE) 
      {
        /* Enable SYSCFG Clock */
        __HAL_RCC_SYSCFG_CLK_ENABLE();
        
        temp = SYSCFG->EXTICR[position >> 2];
        CLEAR_BIT(temp, (0x0FU) << (4 * (position & 0x03)));
        SET_BIT(temp, (GPIO_GET_INDEX(GPIOx)) << (4 * (position & 0x03)));
        SYSCFG->EXTICR[position >> 2] = temp;
                  
        /* Clear EXTI line configuration */
        temp = EXTI->IMR;
        CLEAR_BIT(temp, (uint32_t)iocurrent);
        if((GPIO_Init->Mode & GPIO_MODE_IT) == GPIO_MODE_IT)
        {
          SET_BIT(temp, iocurrent); 
        }
        EXTI->IMR = temp;

        temp = EXTI->EMR;
        CLEAR_BIT(temp, (uint32_t)iocurrent);      
        if((GPIO_Init->Mode & GPIO_MODE_EVT) == GPIO_MODE_EVT)
        {
          SET_BIT(temp, iocurrent); 
        }
        EXTI->EMR = temp;
  
        /* Clear Rising Falling edge configuration */
        temp = EXTI->RTSR;
        CLEAR_BIT(temp, (uint32_t)iocurrent); 
        if((GPIO_Init->Mode & RISING_EDGE) == RISING_EDGE)
        {
          SET_BIT(temp, iocurrent); 
        }
        EXTI->RTSR = temp;

        temp = EXTI->FTSR;
        CLEAR_BIT(temp, (uint32_t)iocurrent); 
        if((GPIO_Init->Mode & FALLING_EDGE) == FALLING_EDGE)
        {
          SET_BIT(temp, iocurrent); 
        }
        EXTI->FTSR = temp;
      }
    }
    
    position++;
  } 
}

/**
  * @brief  De-initializes the GPIOx peripheral registers to their default reset values.
  * @param  GPIOx where x can be (A..G depending on device used) to select the GPIO peripheral for STM32L1XX family devices
  * @param  GPIO_Pin specifies the port bit to be written.
  *         This parameter can be one of GPIO_PIN_x where x can be (0..15).
  * @retval None
  */
void HAL_GPIO_DeInit(GPIO_TypeDef  *GPIOx, uint32_t GPIO_Pin)
{
  uint32_t position = 0x00;
  uint32_t iocurrent = 0x00;
  uint32_t tmp = 0x00;

  /* Check the parameters */
  assert_param(IS_GPIO_ALL_INSTANCE(GPIOx));
  assert_param(IS_GPIO_PIN(GPIO_Pin));

  /* Configure the port pins */
  while ((GPIO_Pin >> position) != 0)
  {
    /* Get current io position */
    iocurrent = (GPIO_Pin) & (1U << position);

    if (iocurrent)
    {
      /*------------------------- EXTI Mode Configuration --------------------*/
      /* Clear the External Interrupt or Event for the current IO */
      
      tmp = SYSCFG->EXTICR[position >> 2];
      tmp &= ((0x0FU) << (4 * (position & 0x03)));
      if(tmp == (GPIO_GET_INDEX(GPIOx) << (4 * (position & 0x03))))
      {
        tmp = (0x0FU) << (4 * (position & 0x03));
        CLEAR_BIT(SYSCFG->EXTICR[position >> 2], tmp);
        
        /* Clear EXTI line configuration */
        CLEAR_BIT(EXTI->IMR, (uint32_t)iocurrent);
        CLEAR_BIT(EXTI->EMR, (uint32_t)iocurrent);
        
        /* Clear Rising Falling edge configuration */
        CLEAR_BIT(EXTI->RTSR, (uint32_t)iocurrent);
        CLEAR_BIT(EXTI->FTSR, (uint32_t)iocurrent);
      }

      /*------------------------- GPIO Mode Configuration --------------------*/
      /* Configure IO Direction in Input Floting Mode */
      CLEAR_BIT(GPIOx->MODER, GPIO_MODER_MODER0 << (position * 2)); 
  
      /* Configure the default Alternate Function in current IO */ 
      CLEAR_BIT(GPIOx->AFR[position >> 3], 0xFU << ((uint32_t)(position & 0x07U) * 4)) ;
  
      /* Configure the default value for IO Speed */
      CLEAR_BIT(GPIOx->OSPEEDR, GPIO_OSPEEDER_OSPEEDR0 << (position * 2));
                  
      /* Configure the default value IO Output Type */
      CLEAR_BIT(GPIOx->OTYPER, GPIO_OTYPER_OT_0 << position) ;
  
      /* Deactivate the Pull-up oand Pull-down resistor for the current IO */
      CLEAR_BIT(GPIOx->PUPDR, GPIO_PUPDR_PUPDR0 << (position * 2));
    }

    position++;
  }
}

/**
  * @}
  */

/** @addtogroup GPIO_Exported_Functions_Group2
 *  @brief GPIO Read, Write, Toggle, Lock and EXTI management functions.
 *
@verbatim   
 ===============================================================================
                       ##### IO operation functions #####
 ===============================================================================  

@endverbatim
  * @{
  */

/**
  * @brief  Reads the specified input port pin.
  * @param  GPIOx where x can be (A..G depending on device used) to select the GPIO peripheral for STM32L1XX family devices 
  * @param  GPIO_Pin specifies the port bit to read.
  *         This parameter can be GPIO_PIN_x where x can be (0..15).
  * @retval The input port pin value.
  */
GPIO_PinState HAL_GPIO_ReadPin(GPIO_TypeDef* GPIOx, uint16_t GPIO_Pin)
{
  GPIO_PinState bitstatus;

  /* Check the parameters */
  assert_param(IS_GPIO_PIN(GPIO_Pin));

  if ((GPIOx->IDR & GPIO_Pin) != (uint32_t)GPIO_PIN_RESET)
  {
    bitstatus = GPIO_PIN_SET;
  }
  else
  {
    bitstatus = GPIO_PIN_RESET;
  }
  return bitstatus;
}

/**
  * @brief  Sets or clears the selected data port bit.
  * @note   This function uses GPIOx_BSRR register to allow atomic read/modify 
  *         accesses. In this way, there is no risk of an IRQ occurring between
  *         the read and the modify access.
  * @param  GPIOx where x can be (A..G depending on device used) to select the GPIO peripheral for STM32L1XX family devices
  * @param  GPIO_Pin specifies the port bit to be written.
  *          This parameter can be one of GPIO_PIN_x where x can be (0..15).
  * @param  PinState specifies the value to be written to the selected bit.
  *          This parameter can be one of the GPIO_PinState enum values:
  *            @arg GPIO_PIN_RESET: to clear the port pin
  *            @arg GPIO_PIN_SET: to set the port pin
  * @retval None
  */
void HAL_GPIO_WritePin(GPIO_TypeDef* GPIOx, uint16_t GPIO_Pin, GPIO_PinState PinState)
{
  /* Check the parameters */
  assert_param(IS_GPIO_PIN(GPIO_Pin));
  assert_param(IS_GPIO_PIN_ACTION(PinState));

  if (PinState != GPIO_PIN_RESET)
  {
    GPIOx->BSRR = (uint32_t)GPIO_Pin;
  }
  else
  {
    GPIOx->BSRR = (uint32_t)GPIO_Pin << 16 ;
  }
}
  
/**
  * @brief  Toggles the specified GPIO pin
  * @param  GPIOx where x can be (A..G depending on device used) to select the GPIO peripheral for STM32L1XX family devices 
  * @param  GPIO_Pin specifies the pins to be toggled.
  * @retval None
  */
void HAL_GPIO_TogglePin(GPIO_TypeDef* GPIOx, uint16_t GPIO_Pin)
{
  /* Check the parameters */
  assert_param(IS_GPIO_PIN(GPIO_Pin));

  if ((GPIOx->ODR & GPIO_Pin) != 0x00u)
  {
    GPIOx->BSRR = (uint32_t)GPIO_Pin << GPIO_NUMBER;
  }
  else
  {
    GPIOx->BSRR = (uint32_t)GPIO_Pin;
  }
}

/**
* @brief  Locks GPIO Pins configuration registers.
* @note   The locked registers are GPIOx_MODER, GPIOx_OTYPER, GPIOx_OSPEEDR,
*         GPIOx_PUPDR, GPIOx_AFRL and GPIOx_AFRH.
* @note   The configuration of the locked GPIO pins can no longer be modified
*         until the next reset.
* @note   Limitation concerning GPIOx_OTYPER: Locking of GPIOx_OTYPER[i] with i = 15..8
*         depends from setting of GPIOx_LCKR[i-8] and not from GPIOx_LCKR[i].
*         GPIOx_LCKR[i-8] is locking GPIOx_OTYPER[i] together with GPIOx_OTYPER[i-8].
*         It is not possible to lock GPIOx_OTYPER[i] with i = 15..8, without locking also
*         GPIOx_OTYPER[i-8].
*         Workaround: When calling HAL_GPIO_LockPin with GPIO_Pin from GPIO_PIN_8 to GPIO_PIN_15,
*         you must call also HAL_GPIO_LockPin with GPIO_Pin - 8. 
*         (When locking a pin from GPIO_PIN_8 to GPIO_PIN_15, you must lock also the corresponding 
*         GPIO_PIN_0 to GPIO_PIN_7).
* @param  GPIOx where x can be (A..G depending on device used) to select the GPIO peripheral for STM32L1XX family devices 
* @param  GPIO_Pin Specifies the port bit to be locked.
*         This parameter can be any combination of GPIO_Pin_x where x can be (0..15).
* @retval None
*/
HAL_StatusTypeDef HAL_GPIO_LockPin(GPIO_TypeDef* GPIOx, uint16_t GPIO_Pin)
{
  __IO uint32_t tmp = GPIO_LCKR_LCKK;

  /* Check the parameters */
  assert_param(IS_GPIO_LOCK_INSTANCE(GPIOx));
  assert_param(IS_GPIO_PIN(GPIO_Pin));

  /* Apply lock key write sequence */
  SET_BIT(tmp, GPIO_Pin);
  /* Set LCKx bit(s): LCKK='1' + LCK[15-0] */
  GPIOx->LCKR = tmp;
  /* Reset LCKx bit(s): LCKK='0' + LCK[15-0] */
  GPIOx->LCKR = GPIO_Pin;
  /* Set LCKx bit(s): LCKK='1' + LCK[15-0] */
  GPIOx->LCKR = tmp;
  /* Read LCKK register. This read is mandatory to complete key lock sequence */
  tmp = GPIOx->LCKR;

  /* Read again in order to confirm lock is active */
  if((GPIOx->LCKR & GPIO_LCKR_LCKK) != RESET)
  {
    return HAL_OK;
  }
  else
  {
    return HAL_ERROR;
  }
}

/**
  * @brief  This function handles EXTI interrupt request.
  * @param  GPIO_Pin Specifies the port pin connected to corresponding EXTI line.
  * @retval None
  */
void HAL_GPIO_EXTI_IRQHandler(uint16_t GPIO_Pin)
{
  /* EXTI line interrupt detected */
  if(__HAL_GPIO_EXTI_GET_IT(GPIO_Pin) != RESET) 
  { 
    __HAL_GPIO_EXTI_CLEAR_IT(GPIO_Pin);
    HAL_GPIO_EXTI_Callback(GPIO_Pin);
  }
}

/**
  * @brief  EXTI line detection callbacks.
  * @param  GPIO_Pin Specifies the port pin connected to corresponding EXTI line.
  * @retval None
  */
__weak void HAL_GPIO_EXTI_Callback(uint16_t GPIO_Pin)
{
  /* Prevent unused argument(s) compilation warning */
  UNUSED(GPIO_Pin);

  /* NOTE : This function Should not be modified, when the callback is needed,
            the HAL_GPIO_EXTI_Callback could be implemented in the user file
   */ 
}

/**
  * @}
  */


/**
  * @}
  */

#endif /* HAL_GPIO_MODULE_ENABLED */
/**
  * @}
  */

/**
  * @}
  */

/************************ (C) COPYRIGHT STMicroelectronics *****END OF FILE****/