1 /**
2 ******************************************************************************
3 * @file stm32l0xx_ll_lpuart.c
4 * @author MCD Application Team
5 * @brief LPUART 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_lpuart.h"
22 #include "stm32l0xx_ll_rcc.h"
23 #include "stm32l0xx_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 STM32L0xx_LL_Driver
31 * @{
32 */
33
34 #if defined (LPUART1)
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 /* __BAUDRATE__ Depending on constraints applicable for LPUART BRR register */
63 /* value : */
64 /* - fck must be in the range [3 x baudrate, 4096 x baudrate] */
65 /* - LPUART_BRR register value should be >= 0x300 */
66 /* - LPUART_BRR register value should be <= 0xFFFFF (20 bits) */
67 /* Baudrate specified by the user should belong to [8, 10600000].*/
68 #define IS_LL_LPUART_BAUDRATE(__BAUDRATE__) (((__BAUDRATE__) <= 10600000U) && ((__BAUDRATE__) >= 8U))
69
70 /* __VALUE__ BRR content must be greater than or equal to 0x300. */
71 #define IS_LL_LPUART_BRR_MIN(__VALUE__) ((__VALUE__) >= 0x300U)
72
73 /* __VALUE__ BRR content must be lower than or equal to 0xFFFFF. */
74 #define IS_LL_LPUART_BRR_MAX(__VALUE__) ((__VALUE__) <= 0x000FFFFFU)
75
76 #define IS_LL_LPUART_DIRECTION(__VALUE__) (((__VALUE__) == LL_LPUART_DIRECTION_NONE) \
77 || ((__VALUE__) == LL_LPUART_DIRECTION_RX) \
78 || ((__VALUE__) == LL_LPUART_DIRECTION_TX) \
79 || ((__VALUE__) == LL_LPUART_DIRECTION_TX_RX))
80
81 #define IS_LL_LPUART_PARITY(__VALUE__) (((__VALUE__) == LL_LPUART_PARITY_NONE) \
82 || ((__VALUE__) == LL_LPUART_PARITY_EVEN) \
83 || ((__VALUE__) == LL_LPUART_PARITY_ODD))
84
85 #define IS_LL_LPUART_DATAWIDTH(__VALUE__) (((__VALUE__) == LL_LPUART_DATAWIDTH_7B) \
86 || ((__VALUE__) == LL_LPUART_DATAWIDTH_8B) \
87 || ((__VALUE__) == LL_LPUART_DATAWIDTH_9B))
88
89 #define IS_LL_LPUART_STOPBITS(__VALUE__) (((__VALUE__) == LL_LPUART_STOPBITS_1) \
90 || ((__VALUE__) == LL_LPUART_STOPBITS_2))
91
92 #define IS_LL_LPUART_HWCONTROL(__VALUE__) (((__VALUE__) == LL_LPUART_HWCONTROL_NONE) \
93 || ((__VALUE__) == LL_LPUART_HWCONTROL_RTS) \
94 || ((__VALUE__) == LL_LPUART_HWCONTROL_CTS) \
95 || ((__VALUE__) == LL_LPUART_HWCONTROL_RTS_CTS))
96
97 /**
98 * @}
99 */
100
101 /* Private function prototypes -----------------------------------------------*/
102
103 /* Exported functions --------------------------------------------------------*/
104 /** @addtogroup LPUART_LL_Exported_Functions
105 * @{
106 */
107
108 /** @addtogroup LPUART_LL_EF_Init
109 * @{
110 */
111
112 /**
113 * @brief De-initialize LPUART registers (Registers restored to their default values).
114 * @param LPUARTx LPUART Instance
115 * @retval An ErrorStatus enumeration value:
116 * - SUCCESS: LPUART registers are de-initialized
117 * - ERROR: not applicable
118 */
LL_LPUART_DeInit(const USART_TypeDef * LPUARTx)119 ErrorStatus LL_LPUART_DeInit(const USART_TypeDef *LPUARTx)
120 {
121 ErrorStatus status = SUCCESS;
122
123 /* Check the parameters */
124 assert_param(IS_LPUART_INSTANCE(LPUARTx));
125
126 if (LPUARTx == LPUART1)
127 {
128 /* Force reset of LPUART peripheral */
129 LL_APB1_GRP1_ForceReset(LL_APB1_GRP1_PERIPH_LPUART1);
130
131 /* Release reset of LPUART peripheral */
132 LL_APB1_GRP1_ReleaseReset(LL_APB1_GRP1_PERIPH_LPUART1);
133 }
134 else
135 {
136 status = ERROR;
137 }
138
139 return (status);
140 }
141
142 /**
143 * @brief Initialize LPUART registers according to the specified
144 * parameters in LPUART_InitStruct.
145 * @note As some bits in LPUART configuration registers can only be written when
146 * the LPUART is disabled (USART_CR1_UE bit =0),
147 * LPUART Peripheral should be in disabled state prior calling this function.
148 * Otherwise, ERROR result will be returned.
149 * @note Baud rate value stored in LPUART_InitStruct BaudRate field, should be valid (different from 0).
150 * @param LPUARTx LPUART Instance
151 * @param LPUART_InitStruct pointer to a @ref LL_LPUART_InitTypeDef structure
152 * that contains the configuration information for the specified LPUART peripheral.
153 * @retval An ErrorStatus enumeration value:
154 * - SUCCESS: LPUART registers are initialized according to LPUART_InitStruct content
155 * - ERROR: Problem occurred during LPUART Registers initialization
156 */
LL_LPUART_Init(USART_TypeDef * LPUARTx,const LL_LPUART_InitTypeDef * LPUART_InitStruct)157 ErrorStatus LL_LPUART_Init(USART_TypeDef *LPUARTx, const LL_LPUART_InitTypeDef *LPUART_InitStruct)
158 {
159 ErrorStatus status = ERROR;
160 uint32_t periphclk;
161
162 /* Check the parameters */
163 assert_param(IS_LPUART_INSTANCE(LPUARTx));
164 assert_param(IS_LL_LPUART_BAUDRATE(LPUART_InitStruct->BaudRate));
165 assert_param(IS_LL_LPUART_DATAWIDTH(LPUART_InitStruct->DataWidth));
166 assert_param(IS_LL_LPUART_STOPBITS(LPUART_InitStruct->StopBits));
167 assert_param(IS_LL_LPUART_PARITY(LPUART_InitStruct->Parity));
168 assert_param(IS_LL_LPUART_DIRECTION(LPUART_InitStruct->TransferDirection));
169 assert_param(IS_LL_LPUART_HWCONTROL(LPUART_InitStruct->HardwareFlowControl));
170
171 /* LPUART needs to be in disabled state, in order to be able to configure some bits in
172 CRx registers. Otherwise (LPUART not in Disabled state) => return ERROR */
173 if (LL_LPUART_IsEnabled(LPUARTx) == 0U)
174 {
175 /*---------------------------- LPUART CR1 Configuration -----------------------
176 * Configure LPUARTx CR1 (LPUART Word Length, Parity and Transfer Direction bits) with parameters:
177 * - DataWidth: USART_CR1_M bits according to LPUART_InitStruct->DataWidth value
178 * - Parity: USART_CR1_PCE, USART_CR1_PS bits according to LPUART_InitStruct->Parity value
179 * - TransferDirection: USART_CR1_TE, USART_CR1_RE bits according to LPUART_InitStruct->TransferDirection value
180 */
181 MODIFY_REG(LPUARTx->CR1,
182 (USART_CR1_M | USART_CR1_PCE | USART_CR1_PS | USART_CR1_TE | USART_CR1_RE),
183 (LPUART_InitStruct->DataWidth | LPUART_InitStruct->Parity | LPUART_InitStruct->TransferDirection));
184
185 /*---------------------------- LPUART CR2 Configuration -----------------------
186 * Configure LPUARTx CR2 (Stop bits) with parameters:
187 * - Stop Bits: USART_CR2_STOP bits according to LPUART_InitStruct->StopBits value.
188 */
189 LL_LPUART_SetStopBitsLength(LPUARTx, LPUART_InitStruct->StopBits);
190
191 /*---------------------------- LPUART CR3 Configuration -----------------------
192 * Configure LPUARTx CR3 (Hardware Flow Control) with parameters:
193 * - HardwareFlowControl: USART_CR3_RTSE, USART_CR3_CTSE bits according
194 * to LPUART_InitStruct->HardwareFlowControl value.
195 */
196 LL_LPUART_SetHWFlowCtrl(LPUARTx, LPUART_InitStruct->HardwareFlowControl);
197
198 /*---------------------------- LPUART BRR Configuration -----------------------
199 * Retrieve Clock frequency used for LPUART Peripheral
200 */
201 periphclk = LL_RCC_GetLPUARTClockFreq(LL_RCC_LPUART1_CLKSOURCE);
202
203 /* Configure the LPUART Baud Rate :
204 - valid baud rate value (different from 0) is required
205 - Peripheral clock as returned by RCC service, should be valid (different from 0).
206 */
207 if ((periphclk != LL_RCC_PERIPH_FREQUENCY_NO)
208 && (LPUART_InitStruct->BaudRate != 0U))
209 {
210 status = SUCCESS;
211 LL_LPUART_SetBaudRate(LPUARTx,
212 periphclk,
213 LPUART_InitStruct->BaudRate);
214
215 /* Check BRR is greater than or equal to 0x300 */
216 assert_param(IS_LL_LPUART_BRR_MIN(LPUARTx->BRR));
217
218 /* Check BRR is lower than or equal to 0xFFFFF */
219 assert_param(IS_LL_LPUART_BRR_MAX(LPUARTx->BRR));
220 }
221
222 }
223
224 return (status);
225 }
226
227 /**
228 * @brief Set each @ref LL_LPUART_InitTypeDef field to default value.
229 * @param LPUART_InitStruct pointer to a @ref LL_LPUART_InitTypeDef structure
230 * whose fields will be set to default values.
231 * @retval None
232 */
233
LL_LPUART_StructInit(LL_LPUART_InitTypeDef * LPUART_InitStruct)234 void LL_LPUART_StructInit(LL_LPUART_InitTypeDef *LPUART_InitStruct)
235 {
236 /* Set LPUART_InitStruct fields to default values */
237 LPUART_InitStruct->BaudRate = LPUART_DEFAULT_BAUDRATE;
238 LPUART_InitStruct->DataWidth = LL_LPUART_DATAWIDTH_8B;
239 LPUART_InitStruct->StopBits = LL_LPUART_STOPBITS_1;
240 LPUART_InitStruct->Parity = LL_LPUART_PARITY_NONE ;
241 LPUART_InitStruct->TransferDirection = LL_LPUART_DIRECTION_TX_RX;
242 LPUART_InitStruct->HardwareFlowControl = LL_LPUART_HWCONTROL_NONE;
243 }
244
245 /**
246 * @}
247 */
248
249 /**
250 * @}
251 */
252
253 /**
254 * @}
255 */
256
257 #endif /* LPUART1 */
258
259 /**
260 * @}
261 */
262
263 #endif /* USE_FULL_LL_DRIVER */
264
