1 /**
2 ******************************************************************************
3 * @file stm32l4xx_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) 2017 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 56MHz (PCLK1) with zero prescaler:
54 max timeout before reset: approximately 73.14us
55 (++) Counter max (T[5;0] = 0x3F) at 56MHz (PCLK1) with prescaler
56 dividing by 8:
57 max timeout before reset: approximately 599.18ms
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 "stm32l4xx_hal.h"
130
131 /** @addtogroup STM32L4xx_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
