drivers/media/dvb-frontends/drx39xyj/bsp_i2c.h

   1 /*
   2   Copyright (c), 2004-2005,2007-2010 Trident Microsystems, Inc.
   3   All rights reserved.
   4
   5   Redistribution and use in source and binary forms, with or without
   6   modification, are permitted provided that the following conditions are met:
   7
   8   * Redistributions of source code must retain the above copyright notice,
   9     this list of conditions and the following disclaimer.
  10   * Redistributions in binary form must reproduce the above copyright notice,
  11     this list of conditions and the following disclaimer in the documentation
  12         and/or other materials provided with the distribution.
  13   * Neither the name of Trident Microsystems nor Hauppauge Computer Works
  14     nor the names of its contributors may be used to endorse or promote
  15         products derived from this software without specific prior written
  16         permission.
  17
  18   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
  19   AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  20   IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  21   ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
  22   LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  23   CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  24   SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  25   INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  26   CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  27   ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  28   POSSIBILITY OF SUCH DAMAGE.
  29 */
  30
  31 /**
  32 * \file $Id: bsp_i2c.h,v 1.5 2009/07/07 14:20:30 justin Exp $
  33 *
  34 * \brief I2C API, implementation depends on board specifics
  35 *
  36 * This module encapsulates I2C access.In some applications several devices
  37 * share one I2C bus. If these devices have the same I2C address some kind
  38 * off "switch" must be implemented to ensure error free communication with
  39 * one device.  In case such a "switch" is used, the device ID can be used
  40 * to implement control over this "switch".
  41 *
  42 *
  43 */
  44
  45 #ifndef __BSPI2C_H__
  46 #define __BSPI2C_H__
  47
  48 #include "bsp_types.h"
  49
  50 /*
  51  * This structure contains the I2C address, the device ID and a userData pointer.
  52  * The userData pointer can be used for application specific purposes.
  53  */
  54 struct i2c_device_addr {
  55         u16 i2cAddr;            /* The I2C address of the device. */
  56         u16 i2cDevId;           /* The device identifier. */
  57         void *userData;         /* User data pointer */
  58 };
  59
  60
  61 /**
  62 * \def IS_I2C_10BIT( addr )
  63 * \brief Determine if I2C address 'addr' is a 10 bits address or not.
  64 * \param addr The I2C address.
  65 * \return int.
  66 * \retval 0 if address is not a 10 bits I2C address.
  67 * \retval 1 if address is a 10 bits I2C address.
  68 */
  69 #define IS_I2C_10BIT(addr) \
  70          (((addr) & 0xF8) == 0xF0)
  71
  72 /*------------------------------------------------------------------------------
  73 Exported FUNCTIONS
  74 ------------------------------------------------------------------------------*/
  75
  76 /**
  77 * \fn DRXBSP_I2C_Init()
  78 * \brief Initialize I2C communication module.
  79 * \return DRXStatus_t Return status.
  80 * \retval DRX_STS_OK Initialization successful.
  81 * \retval DRX_STS_ERROR Initialization failed.
  82 */
  83         DRXStatus_t DRXBSP_I2C_Init(void);
  84
  85 /**
  86 * \fn DRXBSP_I2C_Term()
  87 * \brief Terminate I2C communication module.
  88 * \return DRXStatus_t Return status.
  89 * \retval DRX_STS_OK Termination successful.
  90 * \retval DRX_STS_ERROR Termination failed.
  91 */
  92         DRXStatus_t DRXBSP_I2C_Term(void);
  93
  94 /**
  95 * \fn DRXStatus_t DRXBSP_I2C_WriteRead( struct i2c_device_addr *wDevAddr,
  96 *                                       u16 wCount,
  97 *                                       u8 *wData,
  98 *                                       struct i2c_device_addr *rDevAddr,
  99 *                                       u16 rCount,
 100 *                                       u8 *rData)
 101 * \brief Read and/or write count bytes from I2C bus, store them in data[].
 102 * \param wDevAddr The device i2c address and the device ID to write to
 103 * \param wCount   The number of bytes to write
 104 * \param wData    The array to write the data to
 105 * \param rDevAddr The device i2c address and the device ID to read from
 106 * \param rCount   The number of bytes to read
 107 * \param rData    The array to read the data from
 108 * \return DRXStatus_t Return status.
 109 * \retval DRX_STS_OK Succes.
 110 * \retval DRX_STS_ERROR Failure.
 111 * \retval DRX_STS_INVALID_ARG Parameter 'wcount' is not zero but parameter
 112 *                                       'wdata' contains NULL.
 113 *                                       Idem for 'rcount' and 'rdata'.
 114 *                                       Both wDevAddr and rDevAddr are NULL.
 115 *
 116 * This function must implement an atomic write and/or read action on the I2C bus
 117 * No other process may use the I2C bus when this function is executing.
 118 * The critical section of this function runs from and including the I2C
 119 * write, up to and including the I2C read action.
 120 *
 121 * The device ID can be useful if several devices share an I2C address.
 122 * It can be used to control a "switch" on the I2C bus to the correct device.
 123 */
 124         DRXStatus_t DRXBSP_I2C_WriteRead(struct i2c_device_addr *wDevAddr,
 125                                          u16 wCount,
 126                                          u8 *wData,
 127                                          struct i2c_device_addr *rDevAddr,
 128                                          u16 rCount, u8 *rData);
 129
 130 /**
 131 * \fn DRXBSP_I2C_ErrorText()
 132 * \brief Returns a human readable error.
 133 * Counter part of numerical DRX_I2C_Error_g.
 134 *
 135 * \return char* Pointer to human readable error text.
 136 */
 137         char *DRXBSP_I2C_ErrorText(void);
 138
 139 /**
 140 * \var DRX_I2C_Error_g;
 141 * \brief I2C specific error codes, platform dependent.
 142 */
 143         extern int DRX_I2C_Error_g;
 144
 145 #endif                          /* __BSPI2C_H__ */