1 /**
2 ******************************************************************************
3 * @file stm32l4xx_ll_lpuart.c
4 * @author MCD Application Team
5 * @brief LPUART LL module driver.
6 ******************************************************************************
7 * @attention
8 *
9 * <h2><center>© Copyright (c) 2017 STMicroelectronics.
10 * All rights reserved.</center></h2>
11 *
12 * This software component is licensed by ST under BSD 3-Clause license,
13 * the "License"; You may not use this file except in compliance with the
14 * License. You may obtain a copy of the License at:
15 * opensource.org/licenses/BSD-3-Clause
16 *
17 ******************************************************************************
18 */
19 #if defined(USE_FULL_LL_DRIVER)
20
21 /* Includes ------------------------------------------------------------------*/
22 #include "stm32l4xx_ll_lpuart.h"
23 #include "stm32l4xx_ll_rcc.h"
24 #include "stm32l4xx_ll_bus.h"
25 #ifdef USE_FULL_ASSERT
26 #include "stm32_assert.h"
27 #else
28 #define assert_param(expr) ((void)0U)
29 #endif /* USE_FULL_ASSERT */
30
31 /** @addtogroup STM32L4xx_LL_Driver
32 * @{
33 */
34
35 #if defined (LPUART1)
36
37 /** @addtogroup LPUART_LL
38 * @{
39 */
40
41 /* Private types -------------------------------------------------------------*/
42 /* Private variables ---------------------------------------------------------*/
43 /* Private constants ---------------------------------------------------------*/
44 /** @addtogroup LPUART_LL_Private_Constants
45 * @{
46 */
47
48 /**
49 * @}
50 */
51
52
53 /* Private macros ------------------------------------------------------------*/
54 /** @addtogroup LPUART_LL_Private_Macros
55 * @{
56 */
57
58 /* Check of parameters for configuration of LPUART registers */
59
60 #if defined(USART_PRESC_PRESCALER)
61 #define IS_LL_LPUART_PRESCALER(__VALUE__) (((__VALUE__) == LL_LPUART_PRESCALER_DIV1) \
62 || ((__VALUE__) == LL_LPUART_PRESCALER_DIV2) \
63 || ((__VALUE__) == LL_LPUART_PRESCALER_DIV4) \
64 || ((__VALUE__) == LL_LPUART_PRESCALER_DIV6) \
65 || ((__VALUE__) == LL_LPUART_PRESCALER_DIV8) \
66 || ((__VALUE__) == LL_LPUART_PRESCALER_DIV10) \
67 || ((__VALUE__) == LL_LPUART_PRESCALER_DIV12) \
68 || ((__VALUE__) == LL_LPUART_PRESCALER_DIV16) \
69 || ((__VALUE__) == LL_LPUART_PRESCALER_DIV32) \
70 || ((__VALUE__) == LL_LPUART_PRESCALER_DIV64) \
71 || ((__VALUE__) == LL_LPUART_PRESCALER_DIV128) \
72 || ((__VALUE__) == LL_LPUART_PRESCALER_DIV256))
73
74 #endif /* USART_PRESC_PRESCALER */
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, 40000000].*/
81 #define IS_LL_LPUART_BAUDRATE(__BAUDRATE__) (((__BAUDRATE__) <= 40000000U) && ((__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(USART_TypeDef * LPUARTx)132 ErrorStatus LL_LPUART_DeInit(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_GRP2_ForceReset(LL_APB1_GRP2_PERIPH_LPUART1);
143
144 /* Release reset of LPUART peripheral */
145 LL_APB1_GRP2_ReleaseReset(LL_APB1_GRP2_PERIPH_LPUART1);
146 }
147 else
148 {
149 status = ERROR;
150 }
151
152 return (status);
153 }
154
155 /**
156 * @brief Initialize LPUART registers according to the specified
157 * parameters in LPUART_InitStruct.
158 * @note As some bits in LPUART configuration registers can only be written when the LPUART is disabled (USART_CR1_UE bit =0),
159 * LPUART Peripheral should be in disabled state prior calling this function. Otherwise, ERROR result will be returned.
160 * @note Baud rate value stored in LPUART_InitStruct BaudRate field, should be valid (different from 0).
161 * @param LPUARTx LPUART Instance
162 * @param LPUART_InitStruct pointer to a @ref LL_LPUART_InitTypeDef structure
163 * that contains the configuration information for the specified LPUART peripheral.
164 * @retval An ErrorStatus enumeration value:
165 * - SUCCESS: LPUART registers are initialized according to LPUART_InitStruct content
166 * - ERROR: Problem occurred during LPUART Registers initialization
167 */
LL_LPUART_Init(USART_TypeDef * LPUARTx,LL_LPUART_InitTypeDef * LPUART_InitStruct)168 ErrorStatus LL_LPUART_Init(USART_TypeDef *LPUARTx, LL_LPUART_InitTypeDef *LPUART_InitStruct)
169 {
170 ErrorStatus status = ERROR;
171 uint32_t periphclk;
172
173 /* Check the parameters */
174 assert_param(IS_LPUART_INSTANCE(LPUARTx));
175 #if defined(USART_PRESC_PRESCALER)
176 assert_param(IS_LL_LPUART_PRESCALER(LPUART_InitStruct->PrescalerValue));
177 #endif /* USART_PRESC_PRESCALER */
178 assert_param(IS_LL_LPUART_BAUDRATE(LPUART_InitStruct->BaudRate));
179 assert_param(IS_LL_LPUART_DATAWIDTH(LPUART_InitStruct->DataWidth));
180 assert_param(IS_LL_LPUART_STOPBITS(LPUART_InitStruct->StopBits));
181 assert_param(IS_LL_LPUART_PARITY(LPUART_InitStruct->Parity));
182 assert_param(IS_LL_LPUART_DIRECTION(LPUART_InitStruct->TransferDirection));
183 assert_param(IS_LL_LPUART_HWCONTROL(LPUART_InitStruct->HardwareFlowControl));
184
185 /* LPUART needs to be in disabled state, in order to be able to configure some bits in
186 CRx registers. Otherwise (LPUART not in Disabled state) => return ERROR */
187 if (LL_LPUART_IsEnabled(LPUARTx) == 0U)
188 {
189 /*---------------------------- LPUART CR1 Configuration -----------------------
190 * Configure LPUARTx CR1 (LPUART Word Length, Parity and Transfer Direction bits) with parameters:
191 * - DataWidth: USART_CR1_M bits according to LPUART_InitStruct->DataWidth value
192 * - Parity: USART_CR1_PCE, USART_CR1_PS bits according to LPUART_InitStruct->Parity value
193 * - TransferDirection: USART_CR1_TE, USART_CR1_RE bits according to LPUART_InitStruct->TransferDirection value
194 */
195 MODIFY_REG(LPUARTx->CR1,
196 (USART_CR1_M | USART_CR1_PCE | USART_CR1_PS | USART_CR1_TE | USART_CR1_RE),
197 (LPUART_InitStruct->DataWidth | LPUART_InitStruct->Parity | LPUART_InitStruct->TransferDirection));
198
199 /*---------------------------- LPUART CR2 Configuration -----------------------
200 * Configure LPUARTx CR2 (Stop bits) with parameters:
201 * - Stop Bits: USART_CR2_STOP bits according to LPUART_InitStruct->StopBits value.
202 */
203 LL_LPUART_SetStopBitsLength(LPUARTx, LPUART_InitStruct->StopBits);
204
205 /*---------------------------- LPUART CR3 Configuration -----------------------
206 * Configure LPUARTx CR3 (Hardware Flow Control) with parameters:
207 * - HardwareFlowControl: USART_CR3_RTSE, USART_CR3_CTSE bits according to LPUART_InitStruct->HardwareFlowControl value.
208 */
209 LL_LPUART_SetHWFlowCtrl(LPUARTx, LPUART_InitStruct->HardwareFlowControl);
210
211 /*---------------------------- LPUART BRR Configuration -----------------------
212 * Retrieve Clock frequency used for LPUART Peripheral
213 */
214 periphclk = LL_RCC_GetLPUARTClockFreq(LL_RCC_LPUART1_CLKSOURCE);
215
216 /* Configure the LPUART Baud Rate :
217 #if defined(USART_PRESC_PRESCALER)
218 - prescaler value is required
219 #endif
220 - valid baud rate value (different from 0) is required
221 - Peripheral clock as returned by RCC service, should be valid (different from 0).
222 */
223 if ((periphclk != LL_RCC_PERIPH_FREQUENCY_NO)
224 && (LPUART_InitStruct->BaudRate != 0U))
225 {
226 status = SUCCESS;
227 LL_LPUART_SetBaudRate(LPUARTx,
228 periphclk,
229 #if defined(USART_PRESC_PRESCALER)
230 LPUART_InitStruct->PrescalerValue,
231 #endif /* USART_PRESC_PRESCALER */
232 LPUART_InitStruct->BaudRate);
233
234 /* Check BRR is greater than or equal to 0x300 */
235 assert_param(IS_LL_LPUART_BRR_MIN(LPUARTx->BRR));
236
237 /* Check BRR is lower than or equal to 0xFFFFF */
238 assert_param(IS_LL_LPUART_BRR_MAX(LPUARTx->BRR));
239 }
240
241 #if defined(USART_PRESC_PRESCALER)
242 /*---------------------------- LPUART PRESC Configuration -----------------------
243 * Configure LPUARTx PRESC (Prescaler) with parameters:
244 * - PrescalerValue: LPUART_PRESC_PRESCALER bits according to LPUART_InitStruct->PrescalerValue value.
245 */
246 LL_LPUART_SetPrescaler(LPUARTx, LPUART_InitStruct->PrescalerValue);
247 #endif /* USART_PRESC_PRESCALER */
248 }
249
250 return (status);
251 }
252
253 /**
254 * @brief Set each @ref LL_LPUART_InitTypeDef field to default value.
255 * @param LPUART_InitStruct pointer to a @ref LL_LPUART_InitTypeDef structure
256 * whose fields will be set to default values.
257 * @retval None
258 */
259
LL_LPUART_StructInit(LL_LPUART_InitTypeDef * LPUART_InitStruct)260 void LL_LPUART_StructInit(LL_LPUART_InitTypeDef *LPUART_InitStruct)
261 {
262 /* Set LPUART_InitStruct fields to default values */
263 #if defined(USART_PRESC_PRESCALER)
264 LPUART_InitStruct->PrescalerValue = LL_LPUART_PRESCALER_DIV1;
265 #endif /* USART_PRESC_PRESCALER */
266 LPUART_InitStruct->BaudRate = 9600U;
267 LPUART_InitStruct->DataWidth = LL_LPUART_DATAWIDTH_8B;
268 LPUART_InitStruct->StopBits = LL_LPUART_STOPBITS_1;
269 LPUART_InitStruct->Parity = LL_LPUART_PARITY_NONE ;
270 LPUART_InitStruct->TransferDirection = LL_LPUART_DIRECTION_TX_RX;
271 LPUART_InitStruct->HardwareFlowControl = LL_LPUART_HWCONTROL_NONE;
272 }
273
274 /**
275 * @}
276 */
277
278 /**
279 * @}
280 */
281
282 /**
283 * @}
284 */
285
286 #endif /* defined (LPUART1) */
287
288 /**
289 * @}
290 */
291
292 #endif /* USE_FULL_LL_DRIVER */
293
294 /************************ (C) COPYRIGHT STMicroelectronics *****END OF FILE****/
295
296