1 /**
2   ******************************************************************************
3   * @file    stm32f0xx_hal_wwdg.c
4   * @author  MCD Application Team
5   * @brief   WWDG HAL module driver.
6   *          This file provides firmware functions to manage the following
7   *          functionalities of the Window Watchdog (WWDG) peripheral:
8   *           + Initialization and Configuration functions
9   *           + IO operation functions
10   ******************************************************************************
11   * @attention
12   *
13   * Copyright (c) 2016 STMicroelectronics.
14   * All rights reserved.
15   *
16   * This software is licensed under terms that can be found in the LICENSE file
17   * in the root directory of this software component.
18   * If no LICENSE file comes with this software, it is provided AS-IS.
19   *
20   ******************************************************************************
21   @verbatim
22   ==============================================================================
23                       ##### WWDG Specific features #####
24   ==============================================================================
25   [..]
26     Once enabled the WWDG generates a system reset on expiry of a programmed
27     time period, unless the program refreshes the counter (T[6;0] downcounter)
28     before reaching 0x3F value (i.e. a reset is generated when the counter
29     value rolls down from 0x40 to 0x3F).
30 
31     (+) An MCU reset is also generated if the counter value is refreshed
32         before the counter has reached the refresh window value. This
33         implies that the counter must be refreshed in a limited window.
34     (+) Once enabled the WWDG cannot be disabled except by a system reset.
35     (+) If required by application, an Early Wakeup Interrupt can be triggered
36         in order to be warned before WWDG expiration. The Early Wakeup Interrupt
37         (EWI) can be used if specific safety operations or data logging must
38         be performed before the actual reset is generated. When the downcounter
39         reaches 0x40, interrupt occurs. This mechanism requires WWDG interrupt
40         line to be enabled in NVIC. Once enabled, EWI interrupt cannot be
41         disabled except by a system reset.
42     (+) WWDGRST flag in RCC CSR register can be used to inform when a WWDG
43         reset occurs.
44     (+) The WWDG counter input clock is derived from the APB clock divided
45         by a programmable prescaler.
46     (+) WWDG clock (Hz) = PCLK1 / (4096 * Prescaler)
47     (+) WWDG timeout (mS) = 1000 * (T[5;0] + 1) / WWDG clock (Hz)
48         where T[5;0] are the lowest 6 bits of Counter.
49     (+) WWDG Counter refresh is allowed between the following limits :
50         (++) min time (mS) = 1000 * (Counter - Window) / WWDG clock
51         (++) max time (mS) = 1000 * (Counter - 0x40) / WWDG clock
52     (+) Typical values:
53         (++) Counter min (T[5;0] = 0x00) at 48MHz (PCLK1) with zero prescaler:
54              max timeout before reset: approximately 85.3us
55         (++) Counter max (T[5;0] = 0x3F) at 48MHz (PCLK1) with prescaler
56              dividing by 8:
57              max timeout before reset: approximately 43.7ms
58 
59                      ##### How to use this driver #####
60   ==============================================================================
61 
62     *** Common driver usage ***
63     ===========================
64 
65   [..]
66     (+) Enable WWDG APB1 clock using __HAL_RCC_WWDG_CLK_ENABLE().
67     (+) Configure the WWDG prescaler, refresh window value, counter value and early
68         interrupt status using HAL_WWDG_Init() function. This will automatically
69         enable WWDG and start its downcounter. Time reference can be taken from
70         function exit. Care must be taken to provide a counter value
71         greater than 0x40 to prevent generation of immediate reset.
72     (+) If the Early Wakeup Interrupt (EWI) feature is enabled, an interrupt is
73         generated when the counter reaches 0x40. When HAL_WWDG_IRQHandler is
74         triggered by the interrupt service routine, flag will be automatically
75         cleared and HAL_WWDG_WakeupCallback user callback will be executed. User
76         can add his own code by customization of callback HAL_WWDG_WakeupCallback.
77     (+) Then the application program must refresh the WWDG counter at regular
78         intervals during normal operation to prevent an MCU reset, using
79         HAL_WWDG_Refresh() function. This operation must occur only when
80         the counter is lower than the refresh window value already programmed.
81 
82     *** Callback registration ***
83     =============================
84 
85   [..]
86     The compilation define USE_HAL_WWDG_REGISTER_CALLBACKS when set to 1 allows
87     the user to configure dynamically the driver callbacks. Use Functions
88     HAL_WWDG_RegisterCallback() to register a user callback.
89 
90     (+) Function HAL_WWDG_RegisterCallback() allows to register following
91         callbacks:
92         (++) EwiCallback : callback for Early WakeUp Interrupt.
93         (++) MspInitCallback : WWDG MspInit.
94     This function takes as parameters the HAL peripheral handle, the Callback ID
95     and a pointer to the user callback function.
96 
97     (+) Use function HAL_WWDG_UnRegisterCallback() to reset a callback to
98     the default weak (surcharged) function. HAL_WWDG_UnRegisterCallback()
99     takes as parameters the HAL peripheral handle and the Callback ID.
100     This function allows to reset following callbacks:
101         (++) EwiCallback : callback for  Early WakeUp Interrupt.
102         (++) MspInitCallback : WWDG MspInit.
103 
104     [..]
105     When calling HAL_WWDG_Init function, callbacks are reset to the
106     corresponding legacy weak (surcharged) functions:
107     HAL_WWDG_EarlyWakeupCallback() and HAL_WWDG_MspInit() only if they have
108     not been registered before.
109 
110     [..]
111     When compilation define USE_HAL_WWDG_REGISTER_CALLBACKS is set to 0 or
112     not defined, the callback registering feature is not available
113     and weak (surcharged) callbacks are used.
114 
115     *** WWDG HAL driver macros list ***
116     ===================================
117     [..]
118       Below the list of available macros in WWDG HAL driver.
119       (+) __HAL_WWDG_ENABLE: Enable the WWDG peripheral
120       (+) __HAL_WWDG_GET_FLAG: Get the selected WWDG's flag status
121       (+) __HAL_WWDG_CLEAR_FLAG: Clear the WWDG's pending flags
122       (+) __HAL_WWDG_ENABLE_IT: Enable the WWDG early wakeup interrupt
123 
124   @endverbatim
125   ******************************************************************************
126   */
127 
128 /* Includes ------------------------------------------------------------------*/
129 #include "stm32f0xx_hal.h"
130 
131 /** @addtogroup STM32F0xx_HAL_Driver
132   * @{
133   */
134 
135 #ifdef HAL_WWDG_MODULE_ENABLED
136 /** @defgroup WWDG WWDG
137   * @brief WWDG HAL module driver.
138   * @{
139   */
140 
141 /* Private typedef -----------------------------------------------------------*/
142 /* Private define ------------------------------------------------------------*/
143 /* Private macro -------------------------------------------------------------*/
144 /* Private variables ---------------------------------------------------------*/
145 /* Private function prototypes -----------------------------------------------*/
146 /* Exported functions --------------------------------------------------------*/
147 
148 /** @defgroup WWDG_Exported_Functions WWDG Exported Functions
149   * @{
150   */
151 
152 /** @defgroup WWDG_Exported_Functions_Group1 Initialization and Configuration functions
153   *  @brief    Initialization and Configuration functions.
154   *
155 @verbatim
156   ==============================================================================
157           ##### Initialization and Configuration functions #####
158   ==============================================================================
159   [..]
160     This section provides functions allowing to:
161       (+) Initialize and start the WWDG according to the specified parameters
162           in the WWDG_InitTypeDef of associated handle.
163       (+) Initialize the WWDG MSP.
164 
165 @endverbatim
166   * @{
167   */
168 
169 /**
170   * @brief  Initialize the WWDG according to the specified.
171   *         parameters in the WWDG_InitTypeDef of  associated handle.
172   * @param  hwwdg  pointer to a WWDG_HandleTypeDef structure that contains
173   *                the configuration information for the specified WWDG module.
174   * @retval HAL status
175   */
HAL_WWDG_Init(WWDG_HandleTypeDef * hwwdg)176 HAL_StatusTypeDef HAL_WWDG_Init(WWDG_HandleTypeDef *hwwdg)
177 {
178   /* Check the WWDG handle allocation */
179   if (hwwdg == NULL)
180   {
181     return HAL_ERROR;
182   }
183 
184   /* Check the parameters */
185   assert_param(IS_WWDG_ALL_INSTANCE(hwwdg->Instance));
186   assert_param(IS_WWDG_PRESCALER(hwwdg->Init.Prescaler));
187   assert_param(IS_WWDG_WINDOW(hwwdg->Init.Window));
188   assert_param(IS_WWDG_COUNTER(hwwdg->Init.Counter));
189   assert_param(IS_WWDG_EWI_MODE(hwwdg->Init.EWIMode));
190 
191 #if (USE_HAL_WWDG_REGISTER_CALLBACKS == 1)
192   /* Reset Callback pointers */
193   if (hwwdg->EwiCallback == NULL)
194   {
195     hwwdg->EwiCallback = HAL_WWDG_EarlyWakeupCallback;
196   }
197 
198   if (hwwdg->MspInitCallback == NULL)
199   {
200     hwwdg->MspInitCallback = HAL_WWDG_MspInit;
201   }
202 
203   /* Init the low level hardware */
204   hwwdg->MspInitCallback(hwwdg);
205 #else
206   /* Init the low level hardware */
207   HAL_WWDG_MspInit(hwwdg);
208 #endif /* USE_HAL_WWDG_REGISTER_CALLBACKS */
209 
210   /* Set WWDG Counter */
211   WRITE_REG(hwwdg->Instance->CR, (WWDG_CR_WDGA | hwwdg->Init.Counter));
212 
213   /* Set WWDG Prescaler and Window */
214   WRITE_REG(hwwdg->Instance->CFR, (hwwdg->Init.EWIMode | hwwdg->Init.Prescaler | hwwdg->Init.Window));
215 
216   /* Return function status */
217   return HAL_OK;
218 }
219 
220 
221 /**
222   * @brief  Initialize the WWDG MSP.
223   * @param  hwwdg  pointer to a WWDG_HandleTypeDef structure that contains
224   *                the configuration information for the specified WWDG module.
225   * @note   When rewriting this function in user file, mechanism may be added
226   *         to avoid multiple initialize when HAL_WWDG_Init function is called
227   *         again to change parameters.
228   * @retval None
229   */
HAL_WWDG_MspInit(WWDG_HandleTypeDef * hwwdg)230 __weak void HAL_WWDG_MspInit(WWDG_HandleTypeDef *hwwdg)
231 {
232   /* Prevent unused argument(s) compilation warning */
233   UNUSED(hwwdg);
234 
235   /* NOTE: This function should not be modified, when the callback is needed,
236            the HAL_WWDG_MspInit could be implemented in the user file
237    */
238 }
239 
240 
241 #if (USE_HAL_WWDG_REGISTER_CALLBACKS == 1)
242 /**
243   * @brief  Register a User WWDG Callback
244   *         To be used instead of the weak (surcharged) predefined callback
245   * @param  hwwdg WWDG handle
246   * @param  CallbackID ID of the callback to be registered
247   *         This parameter can be one of the following values:
248   *           @arg @ref HAL_WWDG_EWI_CB_ID Early WakeUp Interrupt Callback ID
249   *           @arg @ref HAL_WWDG_MSPINIT_CB_ID MspInit callback ID
250   * @param  pCallback pointer to the Callback function
251   * @retval status
252   */
HAL_WWDG_RegisterCallback(WWDG_HandleTypeDef * hwwdg,HAL_WWDG_CallbackIDTypeDef CallbackID,pWWDG_CallbackTypeDef pCallback)253 HAL_StatusTypeDef HAL_WWDG_RegisterCallback(WWDG_HandleTypeDef *hwwdg, HAL_WWDG_CallbackIDTypeDef CallbackID,
254                                             pWWDG_CallbackTypeDef pCallback)
255 {
256   HAL_StatusTypeDef status = HAL_OK;
257 
258   if (pCallback == NULL)
259   {
260     status = HAL_ERROR;
261   }
262   else
263   {
264     switch (CallbackID)
265     {
266       case HAL_WWDG_EWI_CB_ID:
267         hwwdg->EwiCallback = pCallback;
268         break;
269 
270       case HAL_WWDG_MSPINIT_CB_ID:
271         hwwdg->MspInitCallback = pCallback;
272         break;
273 
274       default:
275         status = HAL_ERROR;
276         break;
277     }
278   }
279 
280   return status;
281 }
282 
283 
284 /**
285   * @brief  Unregister a WWDG Callback
286   *         WWDG Callback is redirected to the weak (surcharged) predefined callback
287   * @param  hwwdg WWDG handle
288   * @param  CallbackID ID of the callback to be registered
289   *         This parameter can be one of the following values:
290   *           @arg @ref HAL_WWDG_EWI_CB_ID Early WakeUp Interrupt Callback ID
291   *           @arg @ref HAL_WWDG_MSPINIT_CB_ID MspInit callback ID
292   * @retval status
293   */
HAL_WWDG_UnRegisterCallback(WWDG_HandleTypeDef * hwwdg,HAL_WWDG_CallbackIDTypeDef CallbackID)294 HAL_StatusTypeDef HAL_WWDG_UnRegisterCallback(WWDG_HandleTypeDef *hwwdg, HAL_WWDG_CallbackIDTypeDef CallbackID)
295 {
296   HAL_StatusTypeDef status = HAL_OK;
297 
298   switch (CallbackID)
299   {
300     case HAL_WWDG_EWI_CB_ID:
301       hwwdg->EwiCallback = HAL_WWDG_EarlyWakeupCallback;
302       break;
303 
304     case HAL_WWDG_MSPINIT_CB_ID:
305       hwwdg->MspInitCallback = HAL_WWDG_MspInit;
306       break;
307 
308     default:
309       status = HAL_ERROR;
310       break;
311   }
312 
313   return status;
314 }
315 #endif /* USE_HAL_WWDG_REGISTER_CALLBACKS */
316 
317 /**
318   * @}
319   */
320 
321 /** @defgroup WWDG_Exported_Functions_Group2 IO operation functions
322   *  @brief    IO operation functions
323   *
324 @verbatim
325   ==============================================================================
326                       ##### IO operation functions #####
327   ==============================================================================
328   [..]
329     This section provides functions allowing to:
330     (+) Refresh the WWDG.
331     (+) Handle WWDG interrupt request and associated function callback.
332 
333 @endverbatim
334   * @{
335   */
336 
337 /**
338   * @brief  Refresh the WWDG.
339   * @param  hwwdg  pointer to a WWDG_HandleTypeDef structure that contains
340   *                the configuration information for the specified WWDG module.
341   * @retval HAL status
342   */
HAL_WWDG_Refresh(WWDG_HandleTypeDef * hwwdg)343 HAL_StatusTypeDef HAL_WWDG_Refresh(WWDG_HandleTypeDef *hwwdg)
344 {
345   /* Write to WWDG CR the WWDG Counter value to refresh with */
346   WRITE_REG(hwwdg->Instance->CR, (hwwdg->Init.Counter));
347 
348   /* Return function status */
349   return HAL_OK;
350 }
351 
352 /**
353   * @brief  Handle WWDG interrupt request.
354   * @note   The Early Wakeup Interrupt (EWI) can be used if specific safety operations
355   *         or data logging must be performed before the actual reset is generated.
356   *         The EWI interrupt is enabled by calling HAL_WWDG_Init function with
357   *         EWIMode set to WWDG_EWI_ENABLE.
358   *         When the downcounter reaches the value 0x40, and EWI interrupt is
359   *         generated and the corresponding Interrupt Service Routine (ISR) can
360   *         be used to trigger specific actions (such as communications or data
361   *         logging), before resetting the device.
362   * @param  hwwdg  pointer to a WWDG_HandleTypeDef structure that contains
363   *                the configuration information for the specified WWDG module.
364   * @retval None
365   */
HAL_WWDG_IRQHandler(WWDG_HandleTypeDef * hwwdg)366 void HAL_WWDG_IRQHandler(WWDG_HandleTypeDef *hwwdg)
367 {
368   /* Check if Early Wakeup Interrupt is enable */
369   if (__HAL_WWDG_GET_IT_SOURCE(hwwdg, WWDG_IT_EWI) != RESET)
370   {
371     /* Check if WWDG Early Wakeup Interrupt occurred */
372     if (__HAL_WWDG_GET_FLAG(hwwdg, WWDG_FLAG_EWIF) != RESET)
373     {
374       /* Clear the WWDG Early Wakeup flag */
375       __HAL_WWDG_CLEAR_FLAG(hwwdg, WWDG_FLAG_EWIF);
376 
377 #if (USE_HAL_WWDG_REGISTER_CALLBACKS == 1)
378       /* Early Wakeup registered callback */
379       hwwdg->EwiCallback(hwwdg);
380 #else
381       /* Early Wakeup callback */
382       HAL_WWDG_EarlyWakeupCallback(hwwdg);
383 #endif /* USE_HAL_WWDG_REGISTER_CALLBACKS */
384     }
385   }
386 }
387 
388 
389 /**
390   * @brief  WWDG Early Wakeup callback.
391   * @param  hwwdg  pointer to a WWDG_HandleTypeDef structure that contains
392   *                the configuration information for the specified WWDG module.
393   * @retval None
394   */
HAL_WWDG_EarlyWakeupCallback(WWDG_HandleTypeDef * hwwdg)395 __weak void HAL_WWDG_EarlyWakeupCallback(WWDG_HandleTypeDef *hwwdg)
396 {
397   /* Prevent unused argument(s) compilation warning */
398   UNUSED(hwwdg);
399 
400   /* NOTE: This function should not be modified, when the callback is needed,
401            the HAL_WWDG_EarlyWakeupCallback could be implemented in the user file
402    */
403 }
404 
405 /**
406   * @}
407   */
408 
409 /**
410   * @}
411   */
412 
413 #endif /* HAL_WWDG_MODULE_ENABLED */
414 /**
415   * @}
416   */
417 
418 /**
419   * @}
420   */
421