STM32F103xB HAL User Manual
stm32f1xx_ll_spi.c
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00001 /**
00002   ******************************************************************************
00003   * @file    stm32f1xx_ll_spi.c
00004   * @author  MCD Application Team
00005   * @brief   SPI LL module driver.
00006   ******************************************************************************
00007   * @attention
00008   *
00009   * <h2><center>&copy; Copyright (c) 2016 STMicroelectronics.
00010   * All rights reserved.</center></h2>
00011   *
00012   * This software component is licensed by ST under BSD 3-Clause license,
00013   * the "License"; You may not use this file except in compliance with the
00014   * License. You may obtain a copy of the License at:
00015   *                        opensource.org/licenses/BSD-3-Clause
00016   *
00017   ******************************************************************************
00018   */
00019 #if defined(USE_FULL_LL_DRIVER)
00020 
00021 /* Includes ------------------------------------------------------------------*/
00022 #include "stm32f1xx_ll_spi.h"
00023 #include "stm32f1xx_ll_bus.h"
00024 #include "stm32f1xx_ll_rcc.h"
00025 
00026 #ifdef  USE_FULL_ASSERT
00027 #include "stm32_assert.h"
00028 #else
00029 #define assert_param(expr) ((void)0U)
00030 #endif
00031 
00032 /** @addtogroup STM32F1xx_LL_Driver
00033   * @{
00034   */
00035 
00036 #if defined (SPI1) || defined (SPI2) || defined (SPI3)
00037 
00038 /** @addtogroup SPI_LL
00039   * @{
00040   */
00041 
00042 /* Private types -------------------------------------------------------------*/
00043 /* Private variables ---------------------------------------------------------*/
00044 
00045 /* Private constants ---------------------------------------------------------*/
00046 /** @defgroup SPI_LL_Private_Constants SPI Private Constants
00047   * @{
00048   */
00049 /* SPI registers Masks */
00050 #define SPI_CR1_CLEAR_MASK                 (SPI_CR1_CPHA    | SPI_CR1_CPOL     | SPI_CR1_MSTR   | \
00051                                             SPI_CR1_BR      | SPI_CR1_LSBFIRST | SPI_CR1_SSI    | \
00052                                             SPI_CR1_SSM     | SPI_CR1_RXONLY   | SPI_CR1_DFF    | \
00053                                             SPI_CR1_CRCNEXT | SPI_CR1_CRCEN    | SPI_CR1_BIDIOE | \
00054                                             SPI_CR1_BIDIMODE)
00055 /**
00056   * @}
00057   */
00058 
00059 /* Private macros ------------------------------------------------------------*/
00060 /** @defgroup SPI_LL_Private_Macros SPI Private Macros
00061   * @{
00062   */
00063 #define IS_LL_SPI_TRANSFER_DIRECTION(__VALUE__) (((__VALUE__) == LL_SPI_FULL_DUPLEX)       \
00064                                                  || ((__VALUE__) == LL_SPI_SIMPLEX_RX)     \
00065                                                  || ((__VALUE__) == LL_SPI_HALF_DUPLEX_RX) \
00066                                                  || ((__VALUE__) == LL_SPI_HALF_DUPLEX_TX))
00067 
00068 #define IS_LL_SPI_MODE(__VALUE__) (((__VALUE__) == LL_SPI_MODE_MASTER) \
00069                                    || ((__VALUE__) == LL_SPI_MODE_SLAVE))
00070 
00071 #define IS_LL_SPI_DATAWIDTH(__VALUE__) (((__VALUE__) == LL_SPI_DATAWIDTH_8BIT)  \
00072                                         || ((__VALUE__) == LL_SPI_DATAWIDTH_16BIT))
00073 
00074 #define IS_LL_SPI_POLARITY(__VALUE__) (((__VALUE__) == LL_SPI_POLARITY_LOW) \
00075                                        || ((__VALUE__) == LL_SPI_POLARITY_HIGH))
00076 
00077 #define IS_LL_SPI_PHASE(__VALUE__) (((__VALUE__) == LL_SPI_PHASE_1EDGE) \
00078                                     || ((__VALUE__) == LL_SPI_PHASE_2EDGE))
00079 
00080 #define IS_LL_SPI_NSS(__VALUE__) (((__VALUE__) == LL_SPI_NSS_SOFT)          \
00081                                   || ((__VALUE__) == LL_SPI_NSS_HARD_INPUT) \
00082                                   || ((__VALUE__) == LL_SPI_NSS_HARD_OUTPUT))
00083 
00084 #define IS_LL_SPI_BAUDRATE(__VALUE__) (((__VALUE__) == LL_SPI_BAUDRATEPRESCALER_DIV2)      \
00085                                        || ((__VALUE__) == LL_SPI_BAUDRATEPRESCALER_DIV4)   \
00086                                        || ((__VALUE__) == LL_SPI_BAUDRATEPRESCALER_DIV8)   \
00087                                        || ((__VALUE__) == LL_SPI_BAUDRATEPRESCALER_DIV16)  \
00088                                        || ((__VALUE__) == LL_SPI_BAUDRATEPRESCALER_DIV32)  \
00089                                        || ((__VALUE__) == LL_SPI_BAUDRATEPRESCALER_DIV64)  \
00090                                        || ((__VALUE__) == LL_SPI_BAUDRATEPRESCALER_DIV128) \
00091                                        || ((__VALUE__) == LL_SPI_BAUDRATEPRESCALER_DIV256))
00092 
00093 #define IS_LL_SPI_BITORDER(__VALUE__) (((__VALUE__) == LL_SPI_LSB_FIRST) \
00094                                        || ((__VALUE__) == LL_SPI_MSB_FIRST))
00095 
00096 #define IS_LL_SPI_CRCCALCULATION(__VALUE__) (((__VALUE__) == LL_SPI_CRCCALCULATION_ENABLE) \
00097                                              || ((__VALUE__) == LL_SPI_CRCCALCULATION_DISABLE))
00098 
00099 #define IS_LL_SPI_CRC_POLYNOMIAL(__VALUE__) ((__VALUE__) >= 0x1U)
00100 
00101 /**
00102   * @}
00103   */
00104 
00105 /* Private function prototypes -----------------------------------------------*/
00106 
00107 /* Exported functions --------------------------------------------------------*/
00108 /** @addtogroup SPI_LL_Exported_Functions
00109   * @{
00110   */
00111 
00112 /** @addtogroup SPI_LL_EF_Init
00113   * @{
00114   */
00115 
00116 /**
00117   * @brief  De-initialize the SPI registers to their default reset values.
00118   * @param  SPIx SPI Instance
00119   * @retval An ErrorStatus enumeration value:
00120   *          - SUCCESS: SPI registers are de-initialized
00121   *          - ERROR: SPI registers are not de-initialized
00122   */
00123 ErrorStatus LL_SPI_DeInit(SPI_TypeDef *SPIx)
00124 {
00125   ErrorStatus status = ERROR;
00126 
00127   /* Check the parameters */
00128   assert_param(IS_SPI_ALL_INSTANCE(SPIx));
00129 
00130 #if defined(SPI1)
00131   if (SPIx == SPI1)
00132   {
00133     /* Force reset of SPI clock */
00134     LL_APB2_GRP1_ForceReset(LL_APB2_GRP1_PERIPH_SPI1);
00135 
00136     /* Release reset of SPI clock */
00137     LL_APB2_GRP1_ReleaseReset(LL_APB2_GRP1_PERIPH_SPI1);
00138 
00139     status = SUCCESS;
00140   }
00141 #endif /* SPI1 */
00142 #if defined(SPI2)
00143   if (SPIx == SPI2)
00144   {
00145     /* Force reset of SPI clock */
00146     LL_APB1_GRP1_ForceReset(LL_APB1_GRP1_PERIPH_SPI2);
00147 
00148     /* Release reset of SPI clock */
00149     LL_APB1_GRP1_ReleaseReset(LL_APB1_GRP1_PERIPH_SPI2);
00150 
00151     status = SUCCESS;
00152   }
00153 #endif /* SPI2 */
00154 #if defined(SPI3)
00155   if (SPIx == SPI3)
00156   {
00157     /* Force reset of SPI clock */
00158     LL_APB1_GRP1_ForceReset(LL_APB1_GRP1_PERIPH_SPI3);
00159 
00160     /* Release reset of SPI clock */
00161     LL_APB1_GRP1_ReleaseReset(LL_APB1_GRP1_PERIPH_SPI3);
00162 
00163     status = SUCCESS;
00164   }
00165 #endif /* SPI3 */
00166 
00167   return status;
00168 }
00169 
00170 /**
00171   * @brief  Initialize the SPI registers according to the specified parameters in SPI_InitStruct.
00172   * @note   As some bits in SPI configuration registers can only be written when the SPI is disabled (SPI_CR1_SPE bit =0),
00173   *         SPI peripheral should be in disabled state prior calling this function. Otherwise, ERROR result will be returned.
00174   * @param  SPIx SPI Instance
00175   * @param  SPI_InitStruct pointer to a @ref LL_SPI_InitTypeDef structure
00176   * @retval An ErrorStatus enumeration value. (Return always SUCCESS)
00177   */
00178 ErrorStatus LL_SPI_Init(SPI_TypeDef *SPIx, LL_SPI_InitTypeDef *SPI_InitStruct)
00179 {
00180   ErrorStatus status = ERROR;
00181 
00182   /* Check the SPI Instance SPIx*/
00183   assert_param(IS_SPI_ALL_INSTANCE(SPIx));
00184 
00185   /* Check the SPI parameters from SPI_InitStruct*/
00186   assert_param(IS_LL_SPI_TRANSFER_DIRECTION(SPI_InitStruct->TransferDirection));
00187   assert_param(IS_LL_SPI_MODE(SPI_InitStruct->Mode));
00188   assert_param(IS_LL_SPI_DATAWIDTH(SPI_InitStruct->DataWidth));
00189   assert_param(IS_LL_SPI_POLARITY(SPI_InitStruct->ClockPolarity));
00190   assert_param(IS_LL_SPI_PHASE(SPI_InitStruct->ClockPhase));
00191   assert_param(IS_LL_SPI_NSS(SPI_InitStruct->NSS));
00192   assert_param(IS_LL_SPI_BAUDRATE(SPI_InitStruct->BaudRate));
00193   assert_param(IS_LL_SPI_BITORDER(SPI_InitStruct->BitOrder));
00194   assert_param(IS_LL_SPI_CRCCALCULATION(SPI_InitStruct->CRCCalculation));
00195 
00196   if (LL_SPI_IsEnabled(SPIx) == 0x00000000U)
00197   {
00198     /*---------------------------- SPIx CR1 Configuration ------------------------
00199      * Configure SPIx CR1 with parameters:
00200      * - TransferDirection:  SPI_CR1_BIDIMODE, SPI_CR1_BIDIOE and SPI_CR1_RXONLY bits
00201      * - Master/Slave Mode:  SPI_CR1_MSTR bit
00202      * - DataWidth:          SPI_CR1_DFF bit
00203      * - ClockPolarity:      SPI_CR1_CPOL bit
00204      * - ClockPhase:         SPI_CR1_CPHA bit
00205      * - NSS management:     SPI_CR1_SSM bit
00206      * - BaudRate prescaler: SPI_CR1_BR[2:0] bits
00207      * - BitOrder:           SPI_CR1_LSBFIRST bit
00208      * - CRCCalculation:     SPI_CR1_CRCEN bit
00209      */
00210     MODIFY_REG(SPIx->CR1,
00211                SPI_CR1_CLEAR_MASK,
00212                SPI_InitStruct->TransferDirection | SPI_InitStruct->Mode | SPI_InitStruct->DataWidth |
00213                SPI_InitStruct->ClockPolarity | SPI_InitStruct->ClockPhase |
00214                SPI_InitStruct->NSS | SPI_InitStruct->BaudRate |
00215                SPI_InitStruct->BitOrder | SPI_InitStruct->CRCCalculation);
00216 
00217     /*---------------------------- SPIx CR2 Configuration ------------------------
00218      * Configure SPIx CR2 with parameters:
00219      * - NSS management:     SSOE bit
00220      */
00221     MODIFY_REG(SPIx->CR2, SPI_CR2_SSOE, (SPI_InitStruct->NSS >> 16U));
00222 
00223     /*---------------------------- SPIx CRCPR Configuration ----------------------
00224      * Configure SPIx CRCPR with parameters:
00225      * - CRCPoly:            CRCPOLY[15:0] bits
00226      */
00227     if (SPI_InitStruct->CRCCalculation == LL_SPI_CRCCALCULATION_ENABLE)
00228     {
00229       assert_param(IS_LL_SPI_CRC_POLYNOMIAL(SPI_InitStruct->CRCPoly));
00230       LL_SPI_SetCRCPolynomial(SPIx, SPI_InitStruct->CRCPoly);
00231     }
00232     status = SUCCESS;
00233   }
00234 
00235 #if defined (SPI_I2S_SUPPORT)
00236   /* Activate the SPI mode (Reset I2SMOD bit in I2SCFGR register) */
00237   CLEAR_BIT(SPIx->I2SCFGR, SPI_I2SCFGR_I2SMOD);
00238 #endif /* SPI_I2S_SUPPORT */
00239   return status;
00240 }
00241 
00242 /**
00243   * @brief  Set each @ref LL_SPI_InitTypeDef field to default value.
00244   * @param  SPI_InitStruct pointer to a @ref LL_SPI_InitTypeDef structure
00245   * whose fields will be set to default values.
00246   * @retval None
00247   */
00248 void LL_SPI_StructInit(LL_SPI_InitTypeDef *SPI_InitStruct)
00249 {
00250   /* Set SPI_InitStruct fields to default values */
00251   SPI_InitStruct->TransferDirection = LL_SPI_FULL_DUPLEX;
00252   SPI_InitStruct->Mode              = LL_SPI_MODE_SLAVE;
00253   SPI_InitStruct->DataWidth         = LL_SPI_DATAWIDTH_8BIT;
00254   SPI_InitStruct->ClockPolarity     = LL_SPI_POLARITY_LOW;
00255   SPI_InitStruct->ClockPhase        = LL_SPI_PHASE_1EDGE;
00256   SPI_InitStruct->NSS               = LL_SPI_NSS_HARD_INPUT;
00257   SPI_InitStruct->BaudRate          = LL_SPI_BAUDRATEPRESCALER_DIV2;
00258   SPI_InitStruct->BitOrder          = LL_SPI_MSB_FIRST;
00259   SPI_InitStruct->CRCCalculation    = LL_SPI_CRCCALCULATION_DISABLE;
00260   SPI_InitStruct->CRCPoly           = 7U;
00261 }
00262 
00263 /**
00264   * @}
00265   */
00266 
00267 /**
00268   * @}
00269   */
00270 
00271 /**
00272   * @}
00273   */
00274 
00275 #if defined(SPI_I2S_SUPPORT)
00276 /** @addtogroup I2S_LL
00277   * @{
00278   */
00279 
00280 /* Private types -------------------------------------------------------------*/
00281 /* Private variables ---------------------------------------------------------*/
00282 /* Private constants ---------------------------------------------------------*/
00283 /** @defgroup I2S_LL_Private_Constants I2S Private Constants
00284   * @{
00285   */
00286 /* I2S registers Masks */
00287 #define I2S_I2SCFGR_CLEAR_MASK             (SPI_I2SCFGR_CHLEN   | SPI_I2SCFGR_DATLEN | \
00288                                             SPI_I2SCFGR_CKPOL   | SPI_I2SCFGR_I2SSTD | \
00289                                             SPI_I2SCFGR_I2SCFG  | SPI_I2SCFGR_I2SMOD )
00290 
00291 #define I2S_I2SPR_CLEAR_MASK               0x0002U
00292 /**
00293   * @}
00294   */
00295 /* Private macros ------------------------------------------------------------*/
00296 /** @defgroup I2S_LL_Private_Macros I2S Private Macros
00297   * @{
00298   */
00299 
00300 #define IS_LL_I2S_DATAFORMAT(__VALUE__)  (((__VALUE__) == LL_I2S_DATAFORMAT_16B)             \
00301                                           || ((__VALUE__) == LL_I2S_DATAFORMAT_16B_EXTENDED) \
00302                                           || ((__VALUE__) == LL_I2S_DATAFORMAT_24B)          \
00303                                           || ((__VALUE__) == LL_I2S_DATAFORMAT_32B))
00304 
00305 #define IS_LL_I2S_CPOL(__VALUE__)        (((__VALUE__) == LL_I2S_POLARITY_LOW)  \
00306                                           || ((__VALUE__) == LL_I2S_POLARITY_HIGH))
00307 
00308 #define IS_LL_I2S_STANDARD(__VALUE__)    (((__VALUE__) == LL_I2S_STANDARD_PHILIPS)      \
00309                                           || ((__VALUE__) == LL_I2S_STANDARD_MSB)       \
00310                                           || ((__VALUE__) == LL_I2S_STANDARD_LSB)       \
00311                                           || ((__VALUE__) == LL_I2S_STANDARD_PCM_SHORT) \
00312                                           || ((__VALUE__) == LL_I2S_STANDARD_PCM_LONG))
00313 
00314 #define IS_LL_I2S_MODE(__VALUE__)        (((__VALUE__) == LL_I2S_MODE_SLAVE_TX)     \
00315                                           || ((__VALUE__) == LL_I2S_MODE_SLAVE_RX)  \
00316                                           || ((__VALUE__) == LL_I2S_MODE_MASTER_TX) \
00317                                           || ((__VALUE__) == LL_I2S_MODE_MASTER_RX))
00318 
00319 #define IS_LL_I2S_MCLK_OUTPUT(__VALUE__) (((__VALUE__) == LL_I2S_MCLK_OUTPUT_ENABLE) \
00320                                           || ((__VALUE__) == LL_I2S_MCLK_OUTPUT_DISABLE))
00321 
00322 #define IS_LL_I2S_AUDIO_FREQ(__VALUE__) ((((__VALUE__) >= LL_I2S_AUDIOFREQ_8K)       \
00323                                           && ((__VALUE__) <= LL_I2S_AUDIOFREQ_192K)) \
00324                                          || ((__VALUE__) == LL_I2S_AUDIOFREQ_DEFAULT))
00325 
00326 #define IS_LL_I2S_PRESCALER_LINEAR(__VALUE__)  ((__VALUE__) >= 0x2U)
00327 
00328 #define IS_LL_I2S_PRESCALER_PARITY(__VALUE__) (((__VALUE__) == LL_I2S_PRESCALER_PARITY_EVEN) \
00329                                                || ((__VALUE__) == LL_I2S_PRESCALER_PARITY_ODD))
00330 /**
00331   * @}
00332   */
00333 
00334 /* Private function prototypes -----------------------------------------------*/
00335 
00336 /* Exported functions --------------------------------------------------------*/
00337 /** @addtogroup I2S_LL_Exported_Functions
00338   * @{
00339   */
00340 
00341 /** @addtogroup I2S_LL_EF_Init
00342   * @{
00343   */
00344 
00345 /**
00346   * @brief  De-initialize the SPI/I2S registers to their default reset values.
00347   * @param  SPIx SPI Instance
00348   * @retval An ErrorStatus enumeration value:
00349   *          - SUCCESS: SPI registers are de-initialized
00350   *          - ERROR: SPI registers are not de-initialized
00351   */
00352 ErrorStatus LL_I2S_DeInit(SPI_TypeDef *SPIx)
00353 {
00354   return LL_SPI_DeInit(SPIx);
00355 }
00356 
00357 /**
00358   * @brief  Initializes the SPI/I2S registers according to the specified parameters in I2S_InitStruct.
00359   * @note   As some bits in SPI configuration registers can only be written when the SPI is disabled (SPI_CR1_SPE bit =0),
00360   *         SPI peripheral should be in disabled state prior calling this function. Otherwise, ERROR result will be returned.
00361   * @param  SPIx SPI Instance
00362   * @param  I2S_InitStruct pointer to a @ref LL_I2S_InitTypeDef structure
00363   * @retval An ErrorStatus enumeration value:
00364   *          - SUCCESS: SPI registers are Initialized
00365   *          - ERROR: SPI registers are not Initialized
00366   */
00367 ErrorStatus LL_I2S_Init(SPI_TypeDef *SPIx, LL_I2S_InitTypeDef *I2S_InitStruct)
00368 {
00369   uint32_t i2sdiv = 2U;
00370   uint32_t i2sodd = 0U;
00371   uint32_t packetlength = 1U;
00372   uint32_t tmp;
00373   LL_RCC_ClocksTypeDef rcc_clocks;
00374   uint32_t sourceclock;
00375   ErrorStatus status = ERROR;
00376 
00377   /* Check the I2S parameters */
00378   assert_param(IS_I2S_ALL_INSTANCE(SPIx));
00379   assert_param(IS_LL_I2S_MODE(I2S_InitStruct->Mode));
00380   assert_param(IS_LL_I2S_STANDARD(I2S_InitStruct->Standard));
00381   assert_param(IS_LL_I2S_DATAFORMAT(I2S_InitStruct->DataFormat));
00382   assert_param(IS_LL_I2S_MCLK_OUTPUT(I2S_InitStruct->MCLKOutput));
00383   assert_param(IS_LL_I2S_AUDIO_FREQ(I2S_InitStruct->AudioFreq));
00384   assert_param(IS_LL_I2S_CPOL(I2S_InitStruct->ClockPolarity));
00385 
00386   if (LL_I2S_IsEnabled(SPIx) == 0x00000000U)
00387   {
00388     /*---------------------------- SPIx I2SCFGR Configuration --------------------
00389      * Configure SPIx I2SCFGR with parameters:
00390      * - Mode:          SPI_I2SCFGR_I2SCFG[1:0] bit
00391      * - Standard:      SPI_I2SCFGR_I2SSTD[1:0] and SPI_I2SCFGR_PCMSYNC bits
00392      * - DataFormat:    SPI_I2SCFGR_CHLEN and SPI_I2SCFGR_DATLEN bits
00393      * - ClockPolarity: SPI_I2SCFGR_CKPOL bit
00394      */
00395 
00396     /* Write to SPIx I2SCFGR */
00397     MODIFY_REG(SPIx->I2SCFGR,
00398                I2S_I2SCFGR_CLEAR_MASK,
00399                I2S_InitStruct->Mode | I2S_InitStruct->Standard |
00400                I2S_InitStruct->DataFormat | I2S_InitStruct->ClockPolarity |
00401                SPI_I2SCFGR_I2SMOD);
00402 
00403     /*---------------------------- SPIx I2SPR Configuration ----------------------
00404      * Configure SPIx I2SPR with parameters:
00405      * - MCLKOutput:    SPI_I2SPR_MCKOE bit
00406      * - AudioFreq:     SPI_I2SPR_I2SDIV[7:0] and SPI_I2SPR_ODD bits
00407      */
00408 
00409     /* If the requested audio frequency is not the default, compute the prescaler (i2sodd, i2sdiv)
00410      * else, default values are used:  i2sodd = 0U, i2sdiv = 2U.
00411      */
00412     if (I2S_InitStruct->AudioFreq != LL_I2S_AUDIOFREQ_DEFAULT)
00413     {
00414       /* Check the frame length (For the Prescaler computing)
00415        * Default value: LL_I2S_DATAFORMAT_16B (packetlength = 1U).
00416        */
00417       if (I2S_InitStruct->DataFormat != LL_I2S_DATAFORMAT_16B)
00418       {
00419         /* Packet length is 32 bits */
00420         packetlength = 2U;
00421       }
00422 
00423       /* I2S Clock source is System clock: Get System Clock frequency */
00424       LL_RCC_GetSystemClocksFreq(&rcc_clocks);
00425 
00426       /* Get the source clock value: based on System Clock value */
00427       sourceclock = rcc_clocks.SYSCLK_Frequency;
00428 
00429       /* Compute the Real divider depending on the MCLK output state with a floating point */
00430       if (I2S_InitStruct->MCLKOutput == LL_I2S_MCLK_OUTPUT_ENABLE)
00431       {
00432         /* MCLK output is enabled */
00433         tmp = (((((sourceclock / 256U) * 10U) / I2S_InitStruct->AudioFreq)) + 5U);
00434       }
00435       else
00436       {
00437         /* MCLK output is disabled */
00438         tmp = (((((sourceclock / (32U * packetlength)) * 10U) / I2S_InitStruct->AudioFreq)) + 5U);
00439       }
00440 
00441       /* Remove the floating point */
00442       tmp = tmp / 10U;
00443 
00444       /* Check the parity of the divider */
00445       i2sodd = (tmp & (uint16_t)0x0001U);
00446 
00447       /* Compute the i2sdiv prescaler */
00448       i2sdiv = ((tmp - i2sodd) / 2U);
00449 
00450       /* Get the Mask for the Odd bit (SPI_I2SPR[8]) register */
00451       i2sodd = (i2sodd << 8U);
00452     }
00453 
00454     /* Test if the divider is 1 or 0 or greater than 0xFF */
00455     if ((i2sdiv < 2U) || (i2sdiv > 0xFFU))
00456     {
00457       /* Set the default values */
00458       i2sdiv = 2U;
00459       i2sodd = 0U;
00460     }
00461 
00462     /* Write to SPIx I2SPR register the computed value */
00463     WRITE_REG(SPIx->I2SPR, i2sdiv | i2sodd | I2S_InitStruct->MCLKOutput);
00464 
00465     status = SUCCESS;
00466   }
00467   return status;
00468 }
00469 
00470 /**
00471   * @brief  Set each @ref LL_I2S_InitTypeDef field to default value.
00472   * @param  I2S_InitStruct pointer to a @ref LL_I2S_InitTypeDef structure
00473   *         whose fields will be set to default values.
00474   * @retval None
00475   */
00476 void LL_I2S_StructInit(LL_I2S_InitTypeDef *I2S_InitStruct)
00477 {
00478   /*--------------- Reset I2S init structure parameters values -----------------*/
00479   I2S_InitStruct->Mode              = LL_I2S_MODE_SLAVE_TX;
00480   I2S_InitStruct->Standard          = LL_I2S_STANDARD_PHILIPS;
00481   I2S_InitStruct->DataFormat        = LL_I2S_DATAFORMAT_16B;
00482   I2S_InitStruct->MCLKOutput        = LL_I2S_MCLK_OUTPUT_DISABLE;
00483   I2S_InitStruct->AudioFreq         = LL_I2S_AUDIOFREQ_DEFAULT;
00484   I2S_InitStruct->ClockPolarity     = LL_I2S_POLARITY_LOW;
00485 }
00486 
00487 /**
00488   * @brief  Set linear and parity prescaler.
00489   * @note   To calculate value of PrescalerLinear(I2SDIV[7:0] bits) and PrescalerParity(ODD bit)\n
00490   *         Check Audio frequency table and formulas inside Reference Manual (SPI/I2S).
00491   * @param  SPIx SPI Instance
00492   * @param  PrescalerLinear value Min_Data=0x02 and Max_Data=0xFF.
00493   * @param  PrescalerParity This parameter can be one of the following values:
00494   *         @arg @ref LL_I2S_PRESCALER_PARITY_EVEN
00495   *         @arg @ref LL_I2S_PRESCALER_PARITY_ODD
00496   * @retval None
00497   */
00498 void LL_I2S_ConfigPrescaler(SPI_TypeDef *SPIx, uint32_t PrescalerLinear, uint32_t PrescalerParity)
00499 {
00500   /* Check the I2S parameters */
00501   assert_param(IS_I2S_ALL_INSTANCE(SPIx));
00502   assert_param(IS_LL_I2S_PRESCALER_LINEAR(PrescalerLinear));
00503   assert_param(IS_LL_I2S_PRESCALER_PARITY(PrescalerParity));
00504 
00505   /* Write to SPIx I2SPR */
00506   MODIFY_REG(SPIx->I2SPR, SPI_I2SPR_I2SDIV | SPI_I2SPR_ODD, PrescalerLinear | (PrescalerParity << 8U));
00507 }
00508 
00509 /**
00510   * @}
00511   */
00512 
00513 /**
00514   * @}
00515   */
00516 
00517 /**
00518   * @}
00519   */
00520 #endif /* SPI_I2S_SUPPORT */
00521 
00522 #endif /* defined (SPI1) || defined (SPI2) || defined (SPI3) */
00523 
00524 /**
00525   * @}
00526   */
00527 
00528 #endif /* USE_FULL_LL_DRIVER */
00529 
00530 /************************ (C) COPYRIGHT STMicroelectronics *****END OF FILE****/