usb_pwr.c

/**
  ******************************************************************************
  * @file    usb_pwr.c
  * @author  MCD Application Team
  * @version V1.1.0
  * @date    20-September-2012
  * @brief   AConnection/disconnection & power management
  ******************************************************************************
  * @attention
  *
  * <h2><center>&copy; COPYRIGHT 2012 STMicroelectronics</center></h2>
  *
  * Licensed under MCD-ST Liberty SW License Agreement V2, (the "License");
  * You may not use this file except in compliance with the License.
  * You may obtain a copy of the License at:
  *
  *        http://www.st.com/software_license_agreement_liberty_v2
  *
  * Unless required by applicable law or agreed to in writing, software 
  * distributed under the License is distributed on an "AS IS" BASIS, 
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
  * limitations under the License.
  *
  ******************************************************************************
  */
/* Includes ------------------------------------------------------------------*/
#include "stm32f30x.h"
#include "usb_lib.h"
#include "usb_conf.h"
#include "usb_pwr.h"
#include "usb.h"

/** @addtogroup STM32F3-Discovery_Demo
  * @{
  */
  
/* Private typedef -----------------------------------------------------------*/
/* Private define ------------------------------------------------------------*/
/* Private macro -------------------------------------------------------------*/
/* Private variables ---------------------------------------------------------*/
__IO uint32_t bDeviceState = UNCONNECTED; /* USB device status */
__IO bool fSuspendEnabled = TRUE;  /* true when suspend is possible */

struct
{
  __IO RESUME_STATE eState;
  __IO uint8_t bESOFcnt;
}
ResumeS;

/* Extern variables ----------------------------------------------------------*/
/* Private function prototypes -----------------------------------------------*/
/* Extern function prototypes ------------------------------------------------*/
/* Private functions ---------------------------------------------------------*/

/**
  * @brief  PowerOn
  * @param  None.
  * @retval USB_SUCCESS. 
  */
RESULT PowerOn(void)
{
  uint16_t wRegVal;

  /*** cable plugged-in ? ***/
  USB_Cable_Config(ENABLE);

  /*** CNTR_PWDN = 0 ***/
  wRegVal = CNTR_FRES;
  _SetCNTR(wRegVal);

  /*** CNTR_FRES = 0 ***/
  wInterrupt_Mask = 0;
  _SetCNTR(wInterrupt_Mask);
  /*** Clear pending interrupts ***/
  _SetISTR(0);
  /*** Set interrupt mask ***/
  wInterrupt_Mask = CNTR_RESETM | CNTR_SUSPM | CNTR_WKUPM;
  _SetCNTR(wInterrupt_Mask);

  return USB_SUCCESS;
}

/**
  * @brief  handles switch-off conditions
  * @param  None.
  * @retval USB_SUCCESS. 
  */
RESULT PowerOff()
{
  /* disable all interrupts and force USB reset */
  _SetCNTR(CNTR_FRES);
  /* clear interrupt status register */
  _SetISTR(0);
  /* Disable the Pull-Up*/
  USB_Cable_Config(DISABLE);
  /* switch-off device */
  _SetCNTR(CNTR_FRES + CNTR_PDWN);
  /* sw variables reset */
  /* ... */

  return USB_SUCCESS;
}

/**
  * @brief  Sets suspend mode operating conditions
  * @param  None.
  * @retval USB_SUCCESS. 
  */
void Suspend(void)
{
  uint16_t wCNTR;
  /* suspend preparation */
  /* ... */

  /* macrocell enters suspend mode */
  wCNTR = _GetCNTR();
  wCNTR |= CNTR_FSUSP;
  _SetCNTR(wCNTR);

  /* ------------------ ONLY WITH BUS-POWERED DEVICES ---------------------- */
  /* power reduction */
  /* ... on connected devices */


  /* force low-power mode in the macrocell */
  wCNTR = _GetCNTR();
  wCNTR |= CNTR_LPMODE;
  _SetCNTR(wCNTR);

  /* switch-off the clocks */
  /* ... */
  Enter_LowPowerMode();

}

/**
  * @brief  Handles wake-up restoring normal operations
  * @param  None.
  * @retval USB_SUCCESS. 
  */
void Resume_Init(void)
{
  uint16_t wCNTR;

  /* ------------------ ONLY WITH BUS-POWERED DEVICES ---------------------- */
  /* restart the clocks */
  /* ...  */

  /* CNTR_LPMODE = 0 */
  wCNTR = _GetCNTR();
  wCNTR &= (~CNTR_LPMODE);
  _SetCNTR(wCNTR);
    
  
  /* restore full power */
  /* ... on connected devices */
  Leave_LowPowerMode();

  /* reset FSUSP bit */
  _SetCNTR(IMR_MSK);

  /* reverse suspend preparation */
  /* ... */ 

}

/**
  * @brief  This is the state machine handling resume operations and timing sequence.
  *         The control is based on the Resume structure variables and on the ESOF 
  *         interrupt calling this subroutine without changing machine state.
  * @param  eResumeSetVal: a state machine value (RESUME_STATE) RESUME_ESOF doesn't 
  *                        change ResumeS.eState allowing decrementing of the ESOF 
  *                        counter in different states.
  * @retval None. 
  */
void Resume(RESUME_STATE eResumeSetVal)
{
  uint16_t wCNTR;

  if (eResumeSetVal != RESUME_ESOF)
    ResumeS.eState = eResumeSetVal;

  switch (ResumeS.eState)
  {
    case RESUME_EXTERNAL:
      Resume_Init();
      ResumeS.eState = RESUME_OFF;
      break;
    case RESUME_INTERNAL:
      Resume_Init();
      ResumeS.eState = RESUME_START;
      break;
    case RESUME_LATER:
      ResumeS.bESOFcnt = 2;
      ResumeS.eState = RESUME_WAIT;
      break;
    case RESUME_WAIT:
      ResumeS.bESOFcnt--;
      if (ResumeS.bESOFcnt == 0)
        ResumeS.eState = RESUME_START;
      break;
    case RESUME_START:

      wCNTR = _GetCNTR();
      wCNTR |= CNTR_RESUME;
      _SetCNTR(wCNTR);
      ResumeS.eState = RESUME_ON;
      ResumeS.bESOFcnt = 10;
      break;
    case RESUME_ON:
      ResumeS.bESOFcnt--;
      if (ResumeS.bESOFcnt == 0)
      {
        wCNTR = _GetCNTR();
        wCNTR &= (~CNTR_RESUME);
        _SetCNTR(wCNTR);
        ResumeS.eState = RESUME_OFF;
      }
      break;
    case RESUME_OFF:
    case RESUME_ESOF:
    default:
      ResumeS.eState = RESUME_OFF;
      break;
  }
}

/**
  * @}
  */ 

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