1 /**
2   ******************************************************************************
3   * @file    stm32l0xx_ll_lptim.c
4   * @author  MCD Application Team
5   * @brief   LPTIM LL module driver.
6   ******************************************************************************
7   * @attention
8   *
9   * Copyright (c) 2016 STMicroelectronics.
10   * All rights reserved.
11   *
12   * This software is licensed under terms that can be found in the LICENSE file
13   * in the root directory of this software component.
14   * If no LICENSE file comes with this software, it is provided AS-IS.
15   *
16   ******************************************************************************
17   */
18 #if defined(USE_FULL_LL_DRIVER)
19 
20 /* Includes ------------------------------------------------------------------*/
21 #include "stm32l0xx_ll_lptim.h"
22 #include "stm32l0xx_ll_bus.h"
23 #include "stm32l0xx_ll_rcc.h"
24 
25 
26 #ifdef  USE_FULL_ASSERT
27 #include "stm32_assert.h"
28 #else
29 #define assert_param(expr) ((void)0U)
30 #endif /* USE_FULL_ASSERT */
31 
32 /** @addtogroup STM32L0xx_LL_Driver
33   * @{
34   */
35 
36 #if defined (LPTIM1)
37 
38 /** @addtogroup LPTIM_LL
39   * @{
40   */
41 
42 /* Private types -------------------------------------------------------------*/
43 /* Private variables ---------------------------------------------------------*/
44 /* Private constants ---------------------------------------------------------*/
45 /* Private macros ------------------------------------------------------------*/
46 /** @addtogroup LPTIM_LL_Private_Macros
47   * @{
48   */
49 #define IS_LL_LPTIM_CLOCK_SOURCE(__VALUE__) (((__VALUE__) == LL_LPTIM_CLK_SOURCE_INTERNAL) \
50                                              || ((__VALUE__) == LL_LPTIM_CLK_SOURCE_EXTERNAL))
51 
52 #define IS_LL_LPTIM_CLOCK_PRESCALER(__VALUE__) (((__VALUE__) == LL_LPTIM_PRESCALER_DIV1)   \
53                                                 || ((__VALUE__) == LL_LPTIM_PRESCALER_DIV2)   \
54                                                 || ((__VALUE__) == LL_LPTIM_PRESCALER_DIV4)   \
55                                                 || ((__VALUE__) == LL_LPTIM_PRESCALER_DIV8)   \
56                                                 || ((__VALUE__) == LL_LPTIM_PRESCALER_DIV16)  \
57                                                 || ((__VALUE__) == LL_LPTIM_PRESCALER_DIV32)  \
58                                                 || ((__VALUE__) == LL_LPTIM_PRESCALER_DIV64)  \
59                                                 || ((__VALUE__) == LL_LPTIM_PRESCALER_DIV128))
60 
61 #define IS_LL_LPTIM_WAVEFORM(__VALUE__) (((__VALUE__) == LL_LPTIM_OUTPUT_WAVEFORM_PWM) \
62                                          || ((__VALUE__) == LL_LPTIM_OUTPUT_WAVEFORM_SETONCE))
63 
64 #define IS_LL_LPTIM_OUTPUT_POLARITY(__VALUE__) (((__VALUE__) == LL_LPTIM_OUTPUT_POLARITY_REGULAR) \
65                                                 || ((__VALUE__) == LL_LPTIM_OUTPUT_POLARITY_INVERSE))
66 /**
67   * @}
68   */
69 
70 
71 /* Private function prototypes -----------------------------------------------*/
72 /* Private functions ---------------------------------------------------------*/
73 /** @defgroup LPTIM_Private_Functions LPTIM Private Functions
74   * @{
75   */
76 /**
77   * @}
78   */
79 /* Exported functions --------------------------------------------------------*/
80 /** @addtogroup LPTIM_LL_Exported_Functions
81   * @{
82   */
83 
84 /** @addtogroup LPTIM_LL_EF_Init
85   * @{
86   */
87 
88 /**
89   * @brief  Set LPTIMx registers to their reset values.
90   * @param  LPTIMx LP Timer instance
91   * @retval An ErrorStatus enumeration value:
92   *          - SUCCESS: LPTIMx registers are de-initialized
93   *          - ERROR: invalid LPTIMx instance
94   */
LL_LPTIM_DeInit(const LPTIM_TypeDef * LPTIMx)95 ErrorStatus LL_LPTIM_DeInit(const LPTIM_TypeDef *LPTIMx)
96 {
97   ErrorStatus result = SUCCESS;
98 
99   /* Check the parameters */
100   assert_param(IS_LPTIM_INSTANCE(LPTIMx));
101 
102   if (LPTIMx == LPTIM1)
103   {
104     LL_APB1_GRP1_ForceReset(LL_APB1_GRP1_PERIPH_LPTIM1);
105     LL_APB1_GRP1_ReleaseReset(LL_APB1_GRP1_PERIPH_LPTIM1);
106   }
107   else
108   {
109     result = ERROR;
110   }
111 
112   return result;
113 }
114 
115 /**
116   * @brief  Set each fields of the LPTIM_InitStruct structure to its default
117   *         value.
118   * @param  LPTIM_InitStruct pointer to a @ref LL_LPTIM_InitTypeDef structure
119   * @retval None
120   */
LL_LPTIM_StructInit(LL_LPTIM_InitTypeDef * LPTIM_InitStruct)121 void LL_LPTIM_StructInit(LL_LPTIM_InitTypeDef *LPTIM_InitStruct)
122 {
123   /* Set the default configuration */
124   LPTIM_InitStruct->ClockSource = LL_LPTIM_CLK_SOURCE_INTERNAL;
125   LPTIM_InitStruct->Prescaler   = LL_LPTIM_PRESCALER_DIV1;
126   LPTIM_InitStruct->Waveform    = LL_LPTIM_OUTPUT_WAVEFORM_PWM;
127   LPTIM_InitStruct->Polarity    = LL_LPTIM_OUTPUT_POLARITY_REGULAR;
128 }
129 
130 /**
131   * @brief  Configure the LPTIMx peripheral according to the specified parameters.
132   * @note LL_LPTIM_Init can only be called when the LPTIM instance is disabled.
133   * @note LPTIMx can be disabled using unitary function @ref LL_LPTIM_Disable().
134   * @param  LPTIMx LP Timer Instance
135   * @param  LPTIM_InitStruct pointer to a @ref LL_LPTIM_InitTypeDef structure
136   * @retval An ErrorStatus enumeration value:
137   *          - SUCCESS: LPTIMx instance has been initialized
138   *          - ERROR: LPTIMx instance hasn't been initialized
139   */
LL_LPTIM_Init(LPTIM_TypeDef * LPTIMx,const LL_LPTIM_InitTypeDef * LPTIM_InitStruct)140 ErrorStatus LL_LPTIM_Init(LPTIM_TypeDef *LPTIMx, const LL_LPTIM_InitTypeDef *LPTIM_InitStruct)
141 {
142   ErrorStatus result = SUCCESS;
143   /* Check the parameters */
144   assert_param(IS_LPTIM_INSTANCE(LPTIMx));
145   assert_param(IS_LL_LPTIM_CLOCK_SOURCE(LPTIM_InitStruct->ClockSource));
146   assert_param(IS_LL_LPTIM_CLOCK_PRESCALER(LPTIM_InitStruct->Prescaler));
147   assert_param(IS_LL_LPTIM_WAVEFORM(LPTIM_InitStruct->Waveform));
148   assert_param(IS_LL_LPTIM_OUTPUT_POLARITY(LPTIM_InitStruct->Polarity));
149 
150   /* The LPTIMx_CFGR register must only be modified when the LPTIM is disabled
151      (ENABLE bit is reset to 0).
152   */
153   if (LL_LPTIM_IsEnabled(LPTIMx) == 1UL)
154   {
155     result = ERROR;
156   }
157   else
158   {
159     /* Set CKSEL bitfield according to ClockSource value */
160     /* Set PRESC bitfield according to Prescaler value */
161     /* Set WAVE bitfield according to Waveform value */
162     /* Set WAVEPOL bitfield according to Polarity value */
163     MODIFY_REG(LPTIMx->CFGR,
164                (LPTIM_CFGR_CKSEL | LPTIM_CFGR_PRESC | LPTIM_CFGR_WAVE | LPTIM_CFGR_WAVPOL),
165                LPTIM_InitStruct->ClockSource | \
166                LPTIM_InitStruct->Prescaler | \
167                LPTIM_InitStruct->Waveform | \
168                LPTIM_InitStruct->Polarity);
169   }
170 
171   return result;
172 }
173 
174 /**
175   * @brief  Disable the LPTIM instance
176   * @rmtoll CR           ENABLE        LL_LPTIM_Disable
177   * @param  LPTIMx Low-Power Timer instance
178   * @note   The following sequence is required to solve LPTIM disable HW limitation.
179   *         Please check Errata Sheet ES0335 for more details under "MCU may remain
180   *         stuck in LPTIM interrupt when entering Stop mode" section.
181   * @retval None
182   */
LL_LPTIM_Disable(LPTIM_TypeDef * LPTIMx)183 void LL_LPTIM_Disable(LPTIM_TypeDef *LPTIMx)
184 {
185   LL_RCC_ClocksTypeDef rcc_clock;
186   uint32_t tmpclksource = 0;
187   uint32_t tmpIER;
188   uint32_t tmpCFGR;
189   uint32_t tmpCMP;
190   uint32_t tmpARR;
191   uint32_t primask_bit;
192 
193   /* Check the parameters */
194   assert_param(IS_LPTIM_INSTANCE(LPTIMx));
195 
196   /* Enter critical section */
197   primask_bit = __get_PRIMASK();
198   __set_PRIMASK(1) ;
199 
200   /********** Save LPTIM Config *********/
201   /* Save LPTIM source clock */
202   switch ((uint32_t)LPTIMx)
203   {
204     case LPTIM1_BASE:
205       tmpclksource = LL_RCC_GetLPTIMClockSource(LL_RCC_LPTIM1_CLKSOURCE);
206       break;
207     default:
208       break;
209   }
210 
211   /* Save LPTIM configuration registers */
212   tmpIER = LPTIMx->IER;
213   tmpCFGR = LPTIMx->CFGR;
214   tmpCMP = LPTIMx->CMP;
215   tmpARR = LPTIMx->ARR;
216 
217   /************* Reset LPTIM ************/
218   (void)LL_LPTIM_DeInit(LPTIMx);
219 
220   /********* Restore LPTIM Config *******/
221   LL_RCC_GetSystemClocksFreq(&rcc_clock);
222 
223   if ((tmpCMP != 0UL) || (tmpARR != 0UL))
224   {
225     /* Force LPTIM source kernel clock from APB */
226     switch ((uint32_t)LPTIMx)
227     {
228       case LPTIM1_BASE:
229         LL_RCC_SetLPTIMClockSource(LL_RCC_LPTIM1_CLKSOURCE_PCLK1);
230         break;
231       default:
232         break;
233     }
234 
235     if (tmpCMP != 0UL)
236     {
237       /* Restore CMP and ARR registers (LPTIM should be enabled first) */
238       LPTIMx->CR |= LPTIM_CR_ENABLE;
239       LPTIMx->CMP = tmpCMP;
240 
241       /* Polling on CMP write ok status after above restore operation */
242       do
243       {
244         rcc_clock.SYSCLK_Frequency--; /* Used for timeout */
245       } while (((LL_LPTIM_IsActiveFlag_CMPOK(LPTIMx) != 1UL)) && ((rcc_clock.SYSCLK_Frequency) > 0UL));
246 
247       LL_LPTIM_ClearFlag_CMPOK(LPTIMx);
248     }
249 
250     if (tmpARR != 0UL)
251     {
252       LPTIMx->CR |= LPTIM_CR_ENABLE;
253       LPTIMx->ARR = tmpARR;
254 
255       LL_RCC_GetSystemClocksFreq(&rcc_clock);
256       /* Polling on ARR write ok status after above restore operation */
257       do
258       {
259         rcc_clock.SYSCLK_Frequency--; /* Used for timeout */
260       } while (((LL_LPTIM_IsActiveFlag_ARROK(LPTIMx) != 1UL)) && ((rcc_clock.SYSCLK_Frequency) > 0UL));
261 
262       LL_LPTIM_ClearFlag_ARROK(LPTIMx);
263     }
264 
265 
266     /* Restore LPTIM source kernel clock */
267     LL_RCC_SetLPTIMClockSource(tmpclksource);
268   }
269 
270   /* Restore configuration registers (LPTIM should be disabled first) */
271   LPTIMx->CR &= ~(LPTIM_CR_ENABLE);
272   LPTIMx->IER = tmpIER;
273   LPTIMx->CFGR = tmpCFGR;
274 
275   /* Exit critical section: restore previous priority mask */
276   __set_PRIMASK(primask_bit);
277 }
278 
279 /**
280   * @}
281   */
282 
283 /**
284   * @}
285   */
286 
287 /**
288   * @}
289   */
290 
291 #endif /* LPTIM1 */
292 
293 /**
294   * @}
295   */
296 
297 #endif /* USE_FULL_LL_DRIVER */
298