qmk_firmware_custom/drivers/chibios/i2cslave/I2Cv2/hal_i2c_lld.h

/*
    ChibiOS - Copyright (C) 2006..2015 Giovanni Di Sirio

    Licensed under the Apache License, Version 2.0 (the "License");
    you may not use this file except in compliance with the License.
    You may obtain a copy of the License at

        http://www.apache.org/licenses/LICENSE-2.0

    Unless required by applicable law or agreed to in writing, software
    distributed under the License is distributed on an "AS IS" BASIS,
    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    See the License for the specific language governing permissions and
    limitations under the License.
*/
/*
   Concepts and parts of this file have been contributed by Uladzimir Pylinsky
   aka barthess. I2C Slave API for Chibios V2.x V1 I2C originally contributed 
   by Brent Roman (brent@mbari.org), ported to Chibios V3, V2 I2C by steved
 */

/**
 * @file    STM32/I2Cv2/i2c_lld.h
 * @brief   STM32 I2C subsystem low level driver header.
 *
 * @addtogroup I2C
 * @{
 */

#ifndef _I2C_LLD_H_
#define _I2C_LLD_H_

#if HAL_USE_I2C || defined(__DOXYGEN__)

/*===========================================================================*/
/* Driver constants.                                                         */
/*===========================================================================*/

/**
 * @name    TIMINGR register definitions
 * @{
 */
#define STM32_TIMINGR_PRESC_MASK        (15U << 28)
#define STM32_TIMINGR_PRESC(n)          ((n) << 28)
#define STM32_TIMINGR_SCLDEL_MASK       (15U << 20)
#define STM32_TIMINGR_SCLDEL(n)         ((n) << 20)
#define STM32_TIMINGR_SDADEL_MASK       (15U << 16)
#define STM32_TIMINGR_SDADEL(n)         ((n) << 16)
#define STM32_TIMINGR_SCLH_MASK         (255U << 8)
#define STM32_TIMINGR_SCLH(n)           ((n) << 8)
#define STM32_TIMINGR_SCLL_MASK         (255U << 0)
#define STM32_TIMINGR_SCLL(n)           ((n) << 0)
/** @} */


/**
 *	Driver clears down tidily after a timeout
 */
#define I2C_SUPPORT_BUS_CLEAR TRUE

/**
 * @brief   Invalid I2C bus address
 */
#define i2cInvalidAdr  ((i2caddr_t) -1)

/*===========================================================================*/
/* Driver pre-compile time settings.                                         */
/*===========================================================================*/

/**
 * @name    Configuration options
 * @{
 */
/**
 * @brief   I2C1 driver enable switch.
 * @details If set to @p TRUE the support for I2C1 is included.
 * @note    The default is @p FALSE.
 */
#if !defined(STM32_I2C_USE_I2C1) || defined(__DOXYGEN__)
#define STM32_I2C_USE_I2C1                  FALSE
#endif

/**
 * @brief   I2C2 driver enable switch.
 * @details If set to @p TRUE the support for I2C2 is included.
 * @note    The default is @p FALSE.
 */
#if !defined(STM32_I2C_USE_I2C2) || defined(__DOXYGEN__)
#define STM32_I2C_USE_I2C2                  FALSE
#endif

/**
 * @brief   I2C3 driver enable switch.
 * @details If set to @p TRUE the support for I2C3 is included.
 * @note    The default is @p FALSE.
 */
#if !defined(STM32_I2C_USE_I2C3) || defined(__DOXYGEN__)
#define STM32_I2C_USE_I2C3                  FALSE
#endif

/**
 * @brief   I2C4 driver enable switch.
 * @details If set to @p TRUE the support for I2C4 is included.
 * @note    The default is @p FALSE.
 */
#if !defined(STM32_I2C_USE_I2C4) || defined(__DOXYGEN__)
#define STM32_I2C_USE_I2C4                  FALSE
#endif


/**
 *	@brief	Enables support for I2C slave mode operation
 */
#if !defined(HAL_USE_I2C_SLAVE) || defined(__DOXYGEN__)
#define HAL_USE_I2C_SLAVE					FALSE
#endif


/**
 *  @brief  Turns on some debugging options
 */
#if !defined(STM32_I2C_DEBUG_ENABLE) || defined(__DOXYGEN__)
#define STM32_I2C_DEBUG_ENABLE                   FALSE
#endif


/**
 * @brief   I2C timeout on busy condition in milliseconds.
 */
#if !defined(STM32_I2C_BUSY_TIMEOUT) || defined(__DOXYGEN__)
#define STM32_I2C_BUSY_TIMEOUT              50
#endif

/**
 * @brief   I2C1 interrupt priority level setting.
 */
#if !defined(STM32_I2C_I2C1_IRQ_PRIORITY) || defined(__DOXYGEN__)
#define STM32_I2C_I2C1_IRQ_PRIORITY         10
#endif

/**
 * @brief   I2C2 interrupt priority level setting.
 */
#if !defined(STM32_I2C_I2C2_IRQ_PRIORITY) || defined(__DOXYGEN__)
#define STM32_I2C_I2C2_IRQ_PRIORITY         10
#endif

/**
 * @brief   I2C3 interrupt priority level setting.
 */
#if !defined(STM32_I2C_I2C3_IRQ_PRIORITY) || defined(__DOXYGEN__)
#define STM32_I2C_I2C3_IRQ_PRIORITY         10
#endif

/**
 * @brief   I2C4 interrupt priority level setting.
 */
#if !defined(STM32_I2C_I2C4_IRQ_PRIORITY) || defined(__DOXYGEN__)
#define STM32_I2C_I2C4_IRQ_PRIORITY         10
#endif

/**
 * @brief   DMA use switch.
 */
#if !defined(STM32_I2C_USE_DMA) || defined(__DOXYGEN__)
#define STM32_I2C_USE_DMA                   TRUE
#endif

/**
 * @brief   I2C1 DMA priority (0..3|lowest..highest).
 * @note    The priority level is used for both the TX and RX DMA streams but
 *          because of the streams ordering the RX stream has always priority
 *          over the TX stream.
 */
#if !defined(STM32_I2C_I2C1_DMA_PRIORITY) || defined(__DOXYGEN__)
#define STM32_I2C_I2C1_DMA_PRIORITY         1
#endif

/**
 * @brief   I2C2 DMA priority (0..3|lowest..highest).
 * @note    The priority level is used for both the TX and RX DMA streams but
 *          because of the streams ordering the RX stream has always priority
 *          over the TX stream.
 */
#if !defined(STM32_I2C_I2C2_DMA_PRIORITY) || defined(__DOXYGEN__)
#define STM32_I2C_I2C2_DMA_PRIORITY         1
#endif

/**
 * @brief   I2C3 DMA priority (0..3|lowest..highest).
 * @note    The priority level is used for both the TX and RX DMA streams but
 *          because of the streams ordering the RX stream has always priority
 *          over the TX stream.
 */
#if !defined(STM32_I2C_I2C3_DMA_PRIORITY) || defined(__DOXYGEN__)
#define STM32_I2C_I2C3_DMA_PRIORITY         1
#endif

/**
 * @brief   I2C4 DMA priority (0..3|lowest..highest).
 * @note    The priority level is used for both the TX and RX DMA streams but
 *          because of the streams ordering the RX stream has always priority
 *          over the TX stream.
 */
#if !defined(STM32_I2C_I2C4_DMA_PRIORITY) || defined(__DOXYGEN__)
#define STM32_I2C_I2C4_DMA_PRIORITY         1
#endif

/**
 * @brief   I2C DMA error hook.
 * @note    The default action for DMA errors is a system halt because DMA
 *          error can only happen because programming errors.
 */
#if !defined(STM32_I2C_DMA_ERROR_HOOK) || defined(__DOXYGEN__)
#define STM32_I2C_DMA_ERROR_HOOK(i2cp)      osalSysHalt("DMA failure")
#endif
/** @} */


/*===========================================================================*/
/* Derived constants and error checks.                                       */
/*===========================================================================*/

/** @brief  error checks */
#if STM32_I2C_USE_I2C1 && !STM32_HAS_I2C1
#error "I2C1 not present in the selected device"
#endif

#if STM32_I2C_USE_I2C2 && !STM32_HAS_I2C2
#error "I2C2 not present in the selected device"
#endif

#if STM32_I2C_USE_I2C3 && !STM32_HAS_I2C3
#error "I2C3 not present in the selected device"
#endif

#if STM32_I2C_USE_I2C4 && !STM32_HAS_I2C4
#error "I2C4 not present in the selected device"
#endif

#if !STM32_I2C_USE_I2C1 && !STM32_I2C_USE_I2C2 && !STM32_I2C_USE_I2C3 &&    \
    !STM32_I2C_USE_I2C4
#error "I2C driver activated but no I2C peripheral assigned"
#endif

#if STM32_I2C_USE_I2C1 &&                                                   \
    !OSAL_IRQ_IS_VALID_PRIORITY(STM32_I2C_I2C1_IRQ_PRIORITY)
#error "Invalid IRQ priority assigned to I2C1"
#endif

#if STM32_I2C_USE_I2C2 &&                                                   \
    !OSAL_IRQ_IS_VALID_PRIORITY(STM32_I2C_I2C2_IRQ_PRIORITY)
#error "Invalid IRQ priority assigned to I2C2"
#endif

#if STM32_I2C_USE_I2C3 &&                                                   \
    !OSAL_IRQ_IS_VALID_PRIORITY(STM32_I2C_I2C3_IRQ_PRIORITY)
#error "Invalid IRQ priority assigned to I2C3"
#endif

#if STM32_I2C_USE_I2C4 &&                                                   \
    !OSAL_IRQ_IS_VALID_PRIORITY(STM32_I2C_I2C4_IRQ_PRIORITY)
#error "Invalid IRQ priority assigned to I2C4"
#endif

#if STM32_I2C_USE_DMA == TRUE
#if STM32_I2C_USE_I2C1 &&                                                   \
    !STM32_DMA_IS_VALID_PRIORITY(STM32_I2C_I2C1_DMA_PRIORITY)
#error "Invalid DMA priority assigned to I2C1"
#endif

#if STM32_I2C_USE_I2C2 &&                                                   \
    !STM32_DMA_IS_VALID_PRIORITY(STM32_I2C_I2C2_DMA_PRIORITY)
#error "Invalid DMA priority assigned to I2C2"
#endif

#if STM32_I2C_USE_I2C3 &&                                                   \
    !STM32_DMA_IS_VALID_PRIORITY(STM32_I2C_I2C3_DMA_PRIORITY)
#error "Invalid DMA priority assigned to I2C3"
#endif

#if STM32_I2C_USE_I2C4 &&                                                   \
    !STM32_DMA_IS_VALID_PRIORITY(STM32_I2C_I2C4_DMA_PRIORITY)
#error "Invalid DMA priority assigned to I2C4"
#endif

/* The following checks are only required when there is a DMA able to
   reassign streams to different channels.*/
#if STM32_ADVANCED_DMA
/* Check on the presence of the DMA streams settings in mcuconf.h.*/
#if STM32_I2C_USE_I2C1 && (!defined(STM32_I2C_I2C1_RX_DMA_STREAM) ||        \
                           !defined(STM32_I2C_I2C1_TX_DMA_STREAM))
#error "I2C1 DMA streams not defined"
#endif

#if STM32_I2C_USE_I2C2 && (!defined(STM32_I2C_I2C2_RX_DMA_STREAM) ||        \
                           !defined(STM32_I2C_I2C2_TX_DMA_STREAM))
#error "I2C2 DMA streams not defined"
#endif

#if STM32_I2C_USE_I2C3 && (!defined(STM32_I2C_I2C3_RX_DMA_STREAM) ||        \
                           !defined(STM32_I2C_I2C3_TX_DMA_STREAM))
#error "I2C3 DMA streams not defined"
#endif

#if STM32_I2C_USE_I2C4 && (!defined(STM32_I2C_I2C4_RX_DMA_STREAM) ||        \
                           !defined(STM32_I2C_I2C4_TX_DMA_STREAM))
#error "I2C4 DMA streams not defined"
#endif

/* Check on the validity of the assigned DMA channels.*/
#if STM32_I2C_USE_I2C1 &&                                                   \
    !STM32_DMA_IS_VALID_ID(STM32_I2C_I2C1_RX_DMA_STREAM,                    \
                           STM32_I2C1_RX_DMA_MSK)
#error "invalid DMA stream associated to I2C1 RX"
#endif

#if STM32_I2C_USE_I2C1 &&                                                   \
    !STM32_DMA_IS_VALID_ID(STM32_I2C_I2C1_TX_DMA_STREAM,                    \
                           STM32_I2C1_TX_DMA_MSK)
#error "invalid DMA stream associated to I2C1 TX"
#endif

#if STM32_I2C_USE_I2C2 &&                                                   \
    !STM32_DMA_IS_VALID_ID(STM32_I2C_I2C2_RX_DMA_STREAM,                    \
                           STM32_I2C2_RX_DMA_MSK)
#error "invalid DMA stream associated to I2C2 RX"
#endif

#if STM32_I2C_USE_I2C2 &&                                                   \
    !STM32_DMA_IS_VALID_ID(STM32_I2C_I2C2_TX_DMA_STREAM,                    \
                           STM32_I2C2_TX_DMA_MSK)
#error "invalid DMA stream associated to I2C2 TX"
#endif

#if STM32_I2C_USE_I2C3 &&                                                   \
    !STM32_DMA_IS_VALID_ID(STM32_I2C_I2C3_RX_DMA_STREAM,                    \
                           STM32_I2C3_RX_DMA_MSK)
#error "invalid DMA stream associated to I2C3 RX"
#endif

#if STM32_I2C_USE_I2C3 &&                                                   \
    !STM32_DMA_IS_VALID_ID(STM32_I2C_I2C3_TX_DMA_STREAM,                    \
                           STM32_I2C3_TX_DMA_MSK)
#error "invalid DMA stream associated to I2C3 TX"
#endif

#if STM32_I2C_USE_I2C4 &&                                                   \
    !STM32_DMA_IS_VALID_ID(STM32_I2C_I2C4_RX_DMA_STREAM,                    \
                           STM32_I2C4_RX_DMA_MSK)
#error "invalid DMA stream associated to I2C4 RX"
#endif

#if STM32_I2C_USE_I2C4 &&                                                   \
    !STM32_DMA_IS_VALID_ID(STM32_I2C_I2C4_TX_DMA_STREAM,                    \
                           STM32_I2C4_TX_DMA_MSK)
#error "invalid DMA stream associated to I2C4 TX"
#endif
#endif /* STM32_ADVANCED_DMA */

#if !defined(STM32_DMA_REQUIRED)
#define STM32_DMA_REQUIRED
#endif
#endif /* STM32_I2C_USE_DMA == TRUE */



/*===========================================================================*/
/* Driver data structures and types.                                         */
/*===========================================================================*/

/**
 * @brief   Type representing an I2C address.
 * @note	For a 7-bit address, this takes values 0..0x7f, which are then 
 * 				shifted left one and the R/W bit added when required
 */
typedef uint16_t i2caddr_t;

/**
 * @brief   Type of I2C driver condition flags.
 */
typedef uint32_t i2cflags_t;


/**
 * @brief   Type of a structure representing an I2C driver.
 */
typedef struct I2CDriver I2CDriver;


/**
 * @brief   Supported modes for the I2C bus.
 * @note    Currently not used; retained for future enhancements
 */
typedef enum {
  OPMODE_I2C = 1,
  OPMODE_SMBUS_DEVICE = 2,
  OPMODE_SMBUS_HOST = 3,
} i2copmode_t;



/**
 * @brief   Character received I2C notification callback type.
 *
 * @param[in] i2cp      pointer to the @p I2CDriver object
 * @param[in] c         received character
 *
 * @param[out]          Return 0 if transfer to continue. 1 if transfer to be stopped
 *
 * @note        Use only in master mode, to stop a read transaction
 *              once a particular character (or sequence of characters) has been received
 */
typedef uint8_t (*i2cccb_t)(I2CDriver *i2cp, uint16_t c);



/**
 * @brief   Type of I2C driver configuration structure.
 */
typedef struct {
  /**
   * @brief   TIMINGR register initialization.
   * @note    Refer to the STM32 reference manual, the values are affected
   *          by the system clock settings in mcuconf.h.
   */
  uint32_t        timingr;
  /**
   * @brief   CR1 register initialization.
   * @note    Leave to zero unless you know what you are doing.
   */
  uint32_t        cr1;
  /**
   * @brief   CR2 register initialization.
   * @note    Leave at zero except in special circumstances - most bits controlled via API
   */
  uint32_t        cr2;
  /**
   * @brief   Character received callback. Return 0 if transfer to continue. 1 if transfer to be stopped
   * @note    Use only in master mode. Set to NULL if not used.
   */
  i2cccb_t        rxchar_cb;
} I2CConfig;





#if HAL_USE_I2C_SLAVE   /* I2C slave mode support */

typedef struct I2CSlaveMsg I2CSlaveMsg;

/*
  returns the current I2C slave message receive configuration
*/
I2CSlaveMsg *i2cSlaveGetReceiveMsg(I2CDriver *i2cp);


/*
  returns the current I2C slave message reply configuration
*/
I2CSlaveMsg *i2cSlaveGetReplyMsg(I2CDriver *i2cp);


/*
  I2C Slave Message Call Back.
  Invoked from interrupt context just after
  the last byte of the message is transferred or slaveAdr is matched.

  Use i2cSlaveReceiveMsg() or i2cSlaveReplyMsg() to access
  the relevant message handling configuration
*/
typedef void I2CSlaveMsgCB(I2CDriver *i2cp);


/*
  I2CSlaveMsg message handling configurations are normally
  stored in read-only memory.
  They describe either a buffer to contain incoming messages from
  a bus master and associated callback functions, or one
  preloaded with an outgoing reply to a read request and its callbacks.
*/

struct I2CSlaveMsg {
  size_t     size;     			/* sizeof(body) -- zero if master must wait */
  uint8_t   *body;     			/* message contents -- or NULL if master must wait */
  I2CSlaveMsgCB *adrMatched;  	/* invoked when slave address matches */
  I2CSlaveMsgCB *processMsg;  	/* invoked after message is transferred */
  I2CSlaveMsgCB *exception;   	/* invoked if error or timeout during transfer */
};


/*
  dummy callback -- placeholder to ignore event
*/
I2CSlaveMsgCB I2CSlaveDummyCB;

  /* lock bus on receive or reply -- force master to wait */
extern const I2CSlaveMsg I2CSlaveLockOnMsg;

#endif  /* HAL_USE_I2C_SLAVE */




/**
 * @brief   Structure representing an I2C driver.
 */
struct I2CDriver {
  /**
   * @brief   Driver state.
   */
  i2cstate_t                state;
  /**
   * @brief   Current configuration data.
   */
  const I2CConfig           *config;
  /**
   * @brief   Error flags.
   */
  i2cflags_t                errors;
#if I2C_USE_MUTUAL_EXCLUSION || defined(__DOXYGEN__)
  mutex_t                   mutex;
#endif /* I2C_USE_MUTUAL_EXCLUSION */
#if defined(I2C_DRIVER_EXT_FIELDS)
  I2C_DRIVER_EXT_FIELDS
#endif
  /* End of the mandatory fields.*/
  /**
   * @brief   Thread waiting for I/O completion.
   */
  thread_reference_t        thread;


#if (STM32_I2C_USE_DMA == TRUE) || defined(__DOXYGEN__)
  /**
   * @brief RX DMA mode bit mask.
   */
  uint32_t                  rxdmamode;
  /**
   * @brief TX DMA mode bit mask.
   */
  uint32_t                  txdmamode;
  /**
   * @brief     Receive DMA channel.
   */
  const stm32_dma_stream_t  *dmarx;
  /**
   * @brief     Transmit DMA channel.
   */
  const stm32_dma_stream_t  *dmatx;
#else /* STM32_I2C_USE_DMA == FALSE */
  /**
   * @brief     Pointer to the next TX buffer location.
   */
  const uint8_t             *txptr;
  /**
   * @brief     Number of bytes in TX phase.
   */
  size_t                    txbytes;
#endif /* STM32_I2C_USE_DMA == FALSE */
  /**
   * @brief     Pointer to the next RX buffer location.
   */
  uint8_t                   *rxptr;
  /**
   * @brief     Number of bytes in RX phase.
   */
  size_t                    rxbytes;
  /**
   * @brief     Pointer to the I2Cx registers block.
   */
  I2C_TypeDef               *i2c;
  
  
  /**
   * @brief     low level I2C interface / protocol state
   */
  enum i2cMode {
    i2cStopped = 0,		/* Port not initialised, or not started */
    i2cIdle=1,          /* awaiting address or inactive */
    i2cSlaveRxing,      /* receiving message */
    i2cLockedRxing,     /* stretching clock before receiving message - Rx buffer might be full */
    i2cSlaveReplying,   /* replying to query (transmitting, slave mode) */
    i2cLockedReplying,  /* stretching clock before replying to query (no response available from main code) */

    i2cIsMaster=0x11,   /* sent start bit (mastering bus) */
    i2cMasterStarted,   /* repeated start after write */
    i2cMasterSelecting, /* sending slave address */
    i2cMasterRxing,     /* receiving reply from slave */
    i2cMasterTxing      /* sending message to slave */
    }  mode;

#if HAL_USE_I2C_LOCK || HAL_USE_I2C_SLAVE
  /**
   * @brief     I2C transaction timer
   * @note      USed for slave mode, lock
   */
  virtual_timer_t           timer;
#endif
#if HAL_USE_I2C_LOCK
  /**
   * @brief     I2C bus lock duration
   */
  systime_t                 lockDuration;
#endif
#if HAL_USE_I2C_SLAVE
  /* additional fields to support I2C slave transactions */

  /**
   * @brief     slave address of message being processed
   */
  i2caddr_t                 targetAdr;
  /**
   * @brief     Error Mask for last slave message
   */
  i2cflags_t                slaveErrors;
  /**
   * @brief     Length of most recently transferred slave message
   */
  size_t                  slaveBytes;
  /**
   * @brief     Maximum # of ticks slave may stretch the I2C clock
   */
  systime_t                 slaveTimeout;
  /**
   * @brief     Pointer to slave message reception handler
   */
  const I2CSlaveMsg         *slaveRx;
  /**
   * @brief     Pointer to slave message Reply (transmit) handler
   *
   * @note		This is the currently active/just completed reply
   */
  const I2CSlaveMsg         *slaveReply;
  /**
   * @brief     Pointer to handler for next slave received message
   */
  const I2CSlaveMsg         *slaveNextRx;
  /**
   * @brief     Pointer to handler for next slave reply (transmit) message
   *
   * @note		This is used for a reply if no message received first
   */
  const I2CSlaveMsg         *slaveNextReply;
#endif
};

/*===========================================================================*/
/* Driver macros.                                                            */
/*===========================================================================*/

/**
 * @brief   Get errors from I2C driver.
 *
 * @param[in] i2cp      pointer to the @p I2CDriver object
 *
 * @notapi
 */
#define i2c_lld_get_errors(i2cp) ((i2cp)->errors)



#if HAL_USE_I2C_LOCK
/**
 * @brief   Unlock I2C bus after the end of the next transaction
 *
 * @param[in] i2cp      pointer to the @p I2CDriver object
 *
 * @notapi
 **/
#define i2c_lld_unlock(i2cp) (i2cp->lockDuration = TIME_IMMEDIATE)
#endif


#if HAL_USE_I2C_SLAVE   /* I2C slave mode support */
/**
 * @brief   Get slave errors from I2C driver.
 *
 * @param[in] i2cp      pointer to the @p I2CDriver object
 *
 * @notapi
 */
#define i2c_lld_get_slaveErrors(i2cp) ((i2cp)->slaveErrors)

/**
 * @brief   Get slave message bytes transferred from I2C driver.
 *
 * @param[in] i2cp      pointer to the @p I2CDriver object
 *
 * @notapi
 */
#define i2c_lld_get_slaveBytes(i2cp) ((i2cp)->slaveBytes)


/**
 * @brief   Get slave timeout in ticks from I2C driver.
 *
 * @param[in] i2cp      pointer to the @p I2CDriver object
 *
 * @notapi
 */
#define i2c_lld_get_slaveTimeout(i2cp) ((i2cp)->slaveTimeout)

/**
 * @brief   Set slave timeout in ticks for I2C driver.
 *
 * @param[in] i2cp      pointer to the @p I2CDriver object
 *
 * @notapi
 */
#define i2c_lld_set_slaveTimeout(i2cp,ticks) ((i2cp)->slaveTimeout=(ticks))

/**
 * @brief   Get slave target address from I2C driver.
 *
 * @param[in] i2cp      pointer to the @p I2CDriver object
 *
 * @notapi
 */
#define i2c_lld_get_slaveTargetAdr(i2cp) ((i2cp)->targetAdr)

/**
 * @brief   Get slave receive message descriptor from I2C driver.
 *
 * @param[in] i2cp      pointer to the @p I2CDriver object
 *
 * @notapi
 */
#define i2c_lld_get_slaveReceive(i2cp) ((i2cp)->slaveNextRx)

/**
 * @brief   Get slave reply message descriptor from I2C driver.
 *
 * @param[in] i2cp      pointer to the @p I2CDriver object
 *
 * @notapi
 */
#define i2c_lld_get_slaveReply(i2cp) ((i2cp)->slaveNextReply)


#endif


/*===========================================================================*/
/* External declarations.                                                    */
/*===========================================================================*/

#if !defined(__DOXYGEN__)
#if STM32_I2C_USE_I2C1
extern I2CDriver I2CD1;
#endif

#if STM32_I2C_USE_I2C2
extern I2CDriver I2CD2;
#endif

#if STM32_I2C_USE_I2C3
extern I2CDriver I2CD3;
#endif

#if STM32_I2C_USE_I2C4
extern I2CDriver I2CD4;
#endif

#endif /* !defined(__DOXYGEN__) */

#ifdef __cplusplus
extern "C" {
#endif
  void i2c_lld_init(void);
  void i2c_lld_start(I2CDriver *i2cp);
  void i2c_lld_stop(I2CDriver *i2cp);
  msg_t i2c_lld_master_transmit_timeout(I2CDriver *i2cp, i2caddr_t addr,
                                        const uint8_t *txbuf, size_t txbytes,
                                        uint8_t *rxbuf, size_t rxbytes,
                                        systime_t timeout);
  msg_t i2c_lld_master_receive_timeout(I2CDriver *i2cp, i2caddr_t addr,
                                       uint8_t *rxbuf, size_t rxbytes,
                                       systime_t timeout);

#if HAL_USE_I2C_LOCK    /* I2C slave mode support */
  void i2c_lld_lock(I2CDriver *i2cp, systime_t lockDuration);
#endif
#if HAL_USE_I2C_SLAVE   /* I2C slave mode support */
  msg_t i2c_lld_matchAddress(I2CDriver *i2cp, i2caddr_t  i2cadr);
  void  i2c_lld_unmatchAddress(I2CDriver *i2cp, i2caddr_t  i2cadr);
  void  i2c_lld_unmatchAll(I2CDriver *i2cp);
  void  i2c_lld_slaveReceive(I2CDriver *i2cp, const I2CSlaveMsg *rxMsg);
  void  i2c_lld_slaveReply(I2CDriver *i2cp, const I2CSlaveMsg *replyMsg);

#if STM32_I2C_DEBUG_ENABLE
  void i2cPrintQ(BaseSequentialStream *chp);            // Debugging routine
#endif          /* STM32_I2C_DEBUG_ENABLE */

#endif /* HAL_USE_I2C_SLAVE */

#ifdef __cplusplus
}
#endif

#endif /* HAL_USE_I2C  */

#endif /* _I2C_LLD_H_ */

/** @} */