1 /**
2 ******************************************************************************
3 * @file stm32u0xx_ll_lpuart.c
4 * @author MCD Application Team
5 * @brief LPUART LL module driver.
6 ******************************************************************************
7 * @attention
8 *
9 * Copyright (c) 2023 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 "stm32u0xx_ll_lpuart.h"
22 #include "stm32u0xx_ll_rcc.h"
23 #include "stm32u0xx_ll_bus.h"
24 #ifdef USE_FULL_ASSERT
25 #include "stm32_assert.h"
26 #else
27 #define assert_param(expr) ((void)0U)
28 #endif /* USE_FULL_ASSERT */
29
30 /** @addtogroup STM32U0xx_LL_Driver
31 * @{
32 */
33
34 #if defined (LPUART1) || defined (LPUART2) || defined (LPUART3)
35
36 /** @addtogroup LPUART_LL
37 * @{
38 */
39
40 /* Private types -------------------------------------------------------------*/
41 /* Private variables ---------------------------------------------------------*/
42 /* Private constants ---------------------------------------------------------*/
43 /** @addtogroup LPUART_LL_Private_Constants
44 * @{
45 */
46
47 /* Definition of default baudrate value used for LPUART initialisation */
48 #define LPUART_DEFAULT_BAUDRATE (9600U)
49
50 /**
51 * @}
52 */
53
54
55 /* Private macros ------------------------------------------------------------*/
56 /** @addtogroup LPUART_LL_Private_Macros
57 * @{
58 */
59
60 /* Check of parameters for configuration of LPUART registers */
61
62 #define IS_LL_LPUART_PRESCALER(__VALUE__) (((__VALUE__) == LL_LPUART_PRESCALER_DIV1) \
63 || ((__VALUE__) == LL_LPUART_PRESCALER_DIV2) \
64 || ((__VALUE__) == LL_LPUART_PRESCALER_DIV4) \
65 || ((__VALUE__) == LL_LPUART_PRESCALER_DIV6) \
66 || ((__VALUE__) == LL_LPUART_PRESCALER_DIV8) \
67 || ((__VALUE__) == LL_LPUART_PRESCALER_DIV10) \
68 || ((__VALUE__) == LL_LPUART_PRESCALER_DIV12) \
69 || ((__VALUE__) == LL_LPUART_PRESCALER_DIV16) \
70 || ((__VALUE__) == LL_LPUART_PRESCALER_DIV32) \
71 || ((__VALUE__) == LL_LPUART_PRESCALER_DIV64) \
72 || ((__VALUE__) == LL_LPUART_PRESCALER_DIV128) \
73 || ((__VALUE__) == LL_LPUART_PRESCALER_DIV256))
74
75 /* __BAUDRATE__ Depending on constraints applicable for LPUART BRR register */
76 /* value : */
77 /* - fck must be in the range [3 x baudrate, 4096 x baudrate] */
78 /* - LPUART_BRR register value should be >= 0x300 */
79 /* - LPUART_BRR register value should be <= 0xFFFFF (20 bits) */
80 /* Baudrate specified by the user should belong to [8, 16000000].*/
81 #define IS_LL_LPUART_BAUDRATE(__BAUDRATE__) (((__BAUDRATE__) <= 16000000U) && ((__BAUDRATE__) >= 8U))
82
83 /* __VALUE__ BRR content must be greater than or equal to 0x300. */
84 #define IS_LL_LPUART_BRR_MIN(__VALUE__) ((__VALUE__) >= 0x300U)
85
86 /* __VALUE__ BRR content must be lower than or equal to 0xFFFFF. */
87 #define IS_LL_LPUART_BRR_MAX(__VALUE__) ((__VALUE__) <= 0x000FFFFFU)
88
89 #define IS_LL_LPUART_DIRECTION(__VALUE__) (((__VALUE__) == LL_LPUART_DIRECTION_NONE) \
90 || ((__VALUE__) == LL_LPUART_DIRECTION_RX) \
91 || ((__VALUE__) == LL_LPUART_DIRECTION_TX) \
92 || ((__VALUE__) == LL_LPUART_DIRECTION_TX_RX))
93
94 #define IS_LL_LPUART_PARITY(__VALUE__) (((__VALUE__) == LL_LPUART_PARITY_NONE) \
95 || ((__VALUE__) == LL_LPUART_PARITY_EVEN) \
96 || ((__VALUE__) == LL_LPUART_PARITY_ODD))
97
98 #define IS_LL_LPUART_DATAWIDTH(__VALUE__) (((__VALUE__) == LL_LPUART_DATAWIDTH_7B) \
99 || ((__VALUE__) == LL_LPUART_DATAWIDTH_8B) \
100 || ((__VALUE__) == LL_LPUART_DATAWIDTH_9B))
101
102 #define IS_LL_LPUART_STOPBITS(__VALUE__) (((__VALUE__) == LL_LPUART_STOPBITS_1) \
103 || ((__VALUE__) == LL_LPUART_STOPBITS_2))
104
105 #define IS_LL_LPUART_HWCONTROL(__VALUE__) (((__VALUE__) == LL_LPUART_HWCONTROL_NONE) \
106 || ((__VALUE__) == LL_LPUART_HWCONTROL_RTS) \
107 || ((__VALUE__) == LL_LPUART_HWCONTROL_CTS) \
108 || ((__VALUE__) == LL_LPUART_HWCONTROL_RTS_CTS))
109
110 /**
111 * @}
112 */
113
114 /* Private function prototypes -----------------------------------------------*/
115
116 /* Exported functions --------------------------------------------------------*/
117 /** @addtogroup LPUART_LL_Exported_Functions
118 * @{
119 */
120
121 /** @addtogroup LPUART_LL_EF_Init
122 * @{
123 */
124
125 /**
126 * @brief De-initialize LPUART registers (Registers restored to their default values).
127 * @param LPUARTx LPUART Instance
128 * @retval An ErrorStatus enumeration value:
129 * - SUCCESS: LPUART registers are de-initialized
130 * - ERROR: not applicable
131 */
LL_LPUART_DeInit(const USART_TypeDef * LPUARTx)132 ErrorStatus LL_LPUART_DeInit(const USART_TypeDef *LPUARTx)
133 {
134 ErrorStatus status = SUCCESS;
135
136 /* Check the parameters */
137 assert_param(IS_LPUART_INSTANCE(LPUARTx));
138
139 if (LPUARTx == LPUART1)
140 {
141 /* Force reset of LPUART peripheral */
142 LL_APB1_GRP1_ForceReset(LL_APB1_GRP1_PERIPH_LPUART1);
143
144 /* Release reset of LPUART peripheral */
145 LL_APB1_GRP1_ReleaseReset(LL_APB1_GRP1_PERIPH_LPUART1);
146 }
147 else if (LPUARTx == LPUART2)
148 {
149 /* Force reset of LPUART peripheral */
150 LL_APB1_GRP1_ForceReset(LL_APB1_GRP1_PERIPH_LPUART2);
151
152 /* Release reset of LPUART peripheral */
153 LL_APB1_GRP1_ReleaseReset(LL_APB1_GRP1_PERIPH_LPUART2);
154 }
155 #if defined(LPUART3)
156 else if (LPUARTx == LPUART3)
157 {
158 /* Force reset of LPUART peripheral */
159 LL_APB1_GRP1_ForceReset(LL_APB1_GRP1_PERIPH_LPUART3);
160
161 /* Release reset of LPUART peripheral */
162 LL_APB1_GRP1_ReleaseReset(LL_APB1_GRP1_PERIPH_LPUART3);
163 }
164 #endif /* LPUART3 */
165 else
166 {
167 status = ERROR;
168 }
169
170 return (status);
171 }
172
173 /**
174 * @brief Initialize LPUART registers according to the specified
175 * parameters in LPUART_InitStruct.
176 * @note As some bits in LPUART configuration registers can only be written when
177 * the LPUART is disabled (USART_CR1_UE bit =0),
178 * LPUART Peripheral should be in disabled state prior calling this function.
179 * Otherwise, ERROR result will be returned.
180 * @note Baud rate value stored in LPUART_InitStruct BaudRate field, should be valid (different from 0).
181 * @param LPUARTx LPUART Instance
182 * @param LPUART_InitStruct pointer to a @ref LL_LPUART_InitTypeDef structure
183 * that contains the configuration information for the specified LPUART peripheral.
184 * @retval An ErrorStatus enumeration value:
185 * - SUCCESS: LPUART registers are initialized according to LPUART_InitStruct content
186 * - ERROR: Problem occurred during LPUART Registers initialization
187 */
LL_LPUART_Init(USART_TypeDef * LPUARTx,const LL_LPUART_InitTypeDef * LPUART_InitStruct)188 ErrorStatus LL_LPUART_Init(USART_TypeDef *LPUARTx, const LL_LPUART_InitTypeDef *LPUART_InitStruct)
189 {
190 ErrorStatus status = ERROR;
191 uint32_t periphclk = LL_RCC_PERIPH_FREQUENCY_NO;
192
193 /* Check the parameters */
194 assert_param(IS_LPUART_INSTANCE(LPUARTx));
195 assert_param(IS_LL_LPUART_PRESCALER(LPUART_InitStruct->PrescalerValue));
196 assert_param(IS_LL_LPUART_BAUDRATE(LPUART_InitStruct->BaudRate));
197 assert_param(IS_LL_LPUART_DATAWIDTH(LPUART_InitStruct->DataWidth));
198 assert_param(IS_LL_LPUART_STOPBITS(LPUART_InitStruct->StopBits));
199 assert_param(IS_LL_LPUART_PARITY(LPUART_InitStruct->Parity));
200 assert_param(IS_LL_LPUART_DIRECTION(LPUART_InitStruct->TransferDirection));
201 assert_param(IS_LL_LPUART_HWCONTROL(LPUART_InitStruct->HardwareFlowControl));
202
203 /* LPUART needs to be in disabled state, in order to be able to configure some bits in
204 CRx registers. Otherwise (LPUART not in Disabled state) => return ERROR */
205 if (LL_LPUART_IsEnabled(LPUARTx) == 0U)
206 {
207 /*---------------------------- LPUART CR1 Configuration -----------------------
208 * Configure LPUARTx CR1 (LPUART Word Length, Parity and Transfer Direction bits) with parameters:
209 * - DataWidth: USART_CR1_M bits according to LPUART_InitStruct->DataWidth value
210 * - Parity: USART_CR1_PCE, USART_CR1_PS bits according to LPUART_InitStruct->Parity value
211 * - TransferDirection: USART_CR1_TE, USART_CR1_RE bits according to LPUART_InitStruct->TransferDirection value
212 */
213 MODIFY_REG(LPUARTx->CR1,
214 (USART_CR1_M | USART_CR1_PCE | USART_CR1_PS | USART_CR1_TE | USART_CR1_RE),
215 (LPUART_InitStruct->DataWidth | LPUART_InitStruct->Parity | LPUART_InitStruct->TransferDirection));
216
217 /*---------------------------- LPUART CR2 Configuration -----------------------
218 * Configure LPUARTx CR2 (Stop bits) with parameters:
219 * - Stop Bits: USART_CR2_STOP bits according to LPUART_InitStruct->StopBits value.
220 */
221 LL_LPUART_SetStopBitsLength(LPUARTx, LPUART_InitStruct->StopBits);
222
223 /*---------------------------- LPUART CR3 Configuration -----------------------
224 * Configure LPUARTx CR3 (Hardware Flow Control) with parameters:
225 * - HardwareFlowControl: USART_CR3_RTSE, USART_CR3_CTSE bits according
226 * to LPUART_InitStruct->HardwareFlowControl value.
227 */
228 LL_LPUART_SetHWFlowCtrl(LPUARTx, LPUART_InitStruct->HardwareFlowControl);
229
230 /*---------------------------- LPUART BRR Configuration -----------------------
231 * Retrieve Clock frequency used for LPUART Peripheral
232 */
233 if (LPUARTx == LPUART1)
234 {
235 periphclk = LL_RCC_GetLPUARTClockFreq(LL_RCC_LPUART1_CLKSOURCE);
236 }
237 else if (LPUARTx == LPUART2)
238 {
239 periphclk = LL_RCC_GetLPUARTClockFreq(LL_RCC_LPUART2_CLKSOURCE);
240 }
241 #if defined(LPUART3)
242 else if (LPUARTx == LPUART3)
243 {
244 periphclk = LL_RCC_GetLPUARTClockFreq(LL_RCC_LPUART3_CLKSOURCE);
245 }
246 #endif /* LPUART3 */
247 else
248 {
249 /* Nothing to do, as error code is already assigned to ERROR value */
250 }
251
252 /* Configure the LPUART Baud Rate :
253 - prescaler value is required
254 - valid baud rate value (different from 0) is required
255 - Peripheral clock as returned by RCC service, should be valid (different from 0).
256 */
257 if ((periphclk != LL_RCC_PERIPH_FREQUENCY_NO)
258 && (LPUART_InitStruct->BaudRate != 0U))
259 {
260 status = SUCCESS;
261 LL_LPUART_SetBaudRate(LPUARTx,
262 periphclk,
263 LPUART_InitStruct->PrescalerValue,
264 LPUART_InitStruct->BaudRate);
265
266 /* Check BRR is greater than or equal to 0x300 */
267 assert_param(IS_LL_LPUART_BRR_MIN(LPUARTx->BRR));
268
269 /* Check BRR is lower than or equal to 0xFFFFF */
270 assert_param(IS_LL_LPUART_BRR_MAX(LPUARTx->BRR));
271 }
272
273 /*---------------------------- LPUART PRESC Configuration -----------------------
274 * Configure LPUARTx PRESC (Prescaler) with parameters:
275 * - PrescalerValue: LPUART_PRESC_PRESCALER bits according to LPUART_InitStruct->PrescalerValue value.
276 */
277 LL_LPUART_SetPrescaler(LPUARTx, LPUART_InitStruct->PrescalerValue);
278 }
279
280 return (status);
281 }
282
283 /**
284 * @brief Set each @ref LL_LPUART_InitTypeDef field to default value.
285 * @param LPUART_InitStruct pointer to a @ref LL_LPUART_InitTypeDef structure
286 * whose fields will be set to default values.
287 * @retval None
288 */
289
LL_LPUART_StructInit(LL_LPUART_InitTypeDef * LPUART_InitStruct)290 void LL_LPUART_StructInit(LL_LPUART_InitTypeDef *LPUART_InitStruct)
291 {
292 /* Set LPUART_InitStruct fields to default values */
293 LPUART_InitStruct->PrescalerValue = LL_LPUART_PRESCALER_DIV1;
294 LPUART_InitStruct->BaudRate = LPUART_DEFAULT_BAUDRATE;
295 LPUART_InitStruct->DataWidth = LL_LPUART_DATAWIDTH_8B;
296 LPUART_InitStruct->StopBits = LL_LPUART_STOPBITS_1;
297 LPUART_InitStruct->Parity = LL_LPUART_PARITY_NONE ;
298 LPUART_InitStruct->TransferDirection = LL_LPUART_DIRECTION_TX_RX;
299 LPUART_InitStruct->HardwareFlowControl = LL_LPUART_HWCONTROL_NONE;
300 }
301
302 /**
303 * @}
304 */
305
306 /**
307 * @}
308 */
309
310 /**
311 * @}
312 */
313
314 #endif /* LPUART1 || LPUART2 || LPUART3 */
315
316 /**
317 * @}
318 */
319
320 #endif /* USE_FULL_LL_DRIVER */
321
