tinySA/os/hal/platforms/AT91SAM7/i2c_lld.h

/*
    ChibiOS/RT - Copyright (C) 2006,2007,2008,2009,2010,
                 2011,2012,2013 Giovanni Di Sirio.

    This file is part of ChibiOS/RT.

    ChibiOS/RT is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation; either version 3 of the License, or
    (at your option) any later version.

    ChibiOS/RT is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program.  If not, see <http://www.gnu.org/licenses/>.
*/
/*
   Concepts and parts of this file have been contributed by Uladzimir Pylinsky
   aka barthess.
 */

/**
 * @file    AT91SAM7/i2c_lld.h
 * @brief   AT91SAM7 I2C subsystem low level driver header.
 *
 * @addtogroup I2C
 * @{
 */

#ifndef _I2C_LLD_H_
#define _I2C_LLD_H_

#if HAL_USE_I2C || defined(__DOXYGEN__)

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

/**
 * @brief   Peripheral clock frequency.
 */
#define I2C_CLK_FREQ  ((STM32_PCLK1) / 1000000)

/*===========================================================================*/
/* 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(SAM7_I2C_USE_I2C1) || defined(__DOXYGEN__)
#define SAM7_I2C_USE_I2C1              FALSE
#endif

/**
 * @brief   I2C1 interrupt priority level setting.
 */
#if !defined(SAM7_I2C_I2C1_IRQ_PRIORITY) || defined(__DOXYGEN__)
#define SAM7_I2C_I2C1_IRQ_PRIORITY     (AT91C_AIC_PRIOR_HIGHEST - 2)
#endif

/** @} */

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

/** @brief  error checks */
#if !SAM7_I2C_USE_I2C1
#error "I2C driver activated but no I2C peripheral assigned"
#endif

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

/**
 * @brief   Type representing I2C address.
 */
typedef uint16_t i2caddr_t;

/**
 * @brief   I2C Driver condition flags type.
 */
typedef uint32_t i2cflags_t;

/**
 * @brief Driver configuration structure.
 */
typedef struct {
  /**
   * @brief   CWGR regitster content.
   */
  uint32_t                  cwgr;
} I2CConfig;

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

/**
 * @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;
  /**
   * @brief   Pointer to receive buffer.
   */
  uint8_t                   *rxbuf;
  /**
   * @brief   Pointer to transmit buffer.
   */
  const uint8_t             *txbuf;
  /**
   * @brief   Bytes count to be received.
   */
  size_t                    rxbytes;
  /**
   * @brief   Bytes count to be transmitted.
   */
  size_t                    txbytes;
#if I2C_USE_MUTUAL_EXCLUSION || defined(__DOXYGEN__)
#if CH_USE_MUTEXES || defined(__DOXYGEN__)
  /**
   * @brief   Mutex protecting the bus.
   */
  Mutex                     mutex;
#elif CH_USE_SEMAPHORES
  Semaphore                 semaphore;
#endif
#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                    *thread;
};

/*===========================================================================*/
/* 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)

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

#if !defined(__DOXYGEN__)
#if SAM7_I2C_USE_I2C1
extern I2CDriver I2CD1;
#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);
#ifdef __cplusplus
}
#endif

#endif /* HAL_USE_I2C  */

#endif /* _I2C_LLD_H_ */

/** @} */