sys/dev/i2c/i2c_io.h

   1 /*      $NetBSD: i2c_io.h,v 1.1.4.3 2004/09/21 13:27:46 skrll Exp $     */
   2
   3 /*
   4  * Copyright (c) 2003 Wasabi Systems, Inc.
   5  * All rights reserved.
   6  *
   7  * Written by Jason R. Thorpe for Wasabi Systems, Inc.
   8  *
   9  * Redistribution and use in source and binary forms, with or without
  10  * modification, are permitted provided that the following conditions
  11  * are met:
  12  * 1. Redistributions of source code must retain the above copyright
  13  *    notice, this list of conditions and the following disclaimer.
  14  * 2. Redistributions in binary form must reproduce the above copyright
  15  *    notice, this list of conditions and the following disclaimer in the
  16  *    documentation and/or other materials provided with the distribution.
  17  * 3. All advertising materials mentioning features or use of this software
  18  *    must display the following acknowledgement:
  19  *      This product includes software developed for the NetBSD Project by
  20  *      Wasabi Systems, Inc.
  21  * 4. The name of Wasabi Systems, Inc. may not be used to endorse
  22  *    or promote products derived from this software without specific prior
  23  *    written permission.
  24  *
  25  * THIS SOFTWARE IS PROVIDED BY WASABI SYSTEMS, INC. ``AS IS'' AND
  26  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
  27  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  28  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL WASABI SYSTEMS, INC
  29  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  30  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  31  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  32  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  33  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  34  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  35  * POSSIBILITY OF SUCH DAMAGE.
  36  */
  37
  38 #ifndef _DEV_I2C_I2C_IO_H_
  39 #define _DEV_I2C_I2C_IO_H_
  40
  41 #include <sys/ioccom.h>
  42
  43 /* I2C bus address. */
  44 typedef uint16_t i2c_addr_t;
  45
  46 /* High-level I2C operations. */
  47 typedef enum {
  48         I2C_OP_READ             = 0,
  49         I2C_OP_READ_WITH_STOP   = 1,
  50         I2C_OP_WRITE            = 2,
  51         I2C_OP_WRITE_WITH_STOP  = 3,
  52 } i2c_op_t;
  53
  54 #define I2C_OP_READ_P(x)        (((int)(x) & 2) == 0)
  55 #define I2C_OP_WRITE_P(x)       (! I2C_OP_READ_P(x))
  56 #define I2C_OP_STOP_P(x)        (((int)(x) & 1) != 0)
  57
  58 /*
  59  * This structure describes a single I2C control script fragment.
  60  *
  61  * Note that use of this scripted API allows for support of automated
  62  * SMBus controllers.  The following table maps SMBus operations to
  63  * script fragment configuration:
  64  *
  65  *      SMBus "write byte":             I2C_OP_WRITE_WITH_STOP
  66  *                                      cmdlen = 1
  67  *
  68  *      SMBus "read byte":              I2C_OP_READ_WITH_STOP
  69  *                                      cmdlen = 1
  70  *
  71  *      SMBus "receive byte":           I2C_OP_READ_WITH_STOP
  72  *                                      cmdlen = 0
  73  *
  74  * Note that while each of these 3 SMBus operations implies a STOP
  75  * (which an automated controller will likely perform automatically),
  76  * non-SMBus clients may continue to function even if they issue
  77  * I2C_OP_WRITE and I2C_OP_READ.
  78  */
  79
  80 /*
  81  * I2C_IOCTL_EXEC:
  82  *
  83  *      User ioctl to execute an i2c operation.
  84  */
  85 typedef struct i2c_ioctl_exec {
  86         i2c_op_t iie_op;                /* operation to perform */
  87         i2c_addr_t iie_addr;            /* address of device */
  88         const void *iie_cmd;            /* pointer to command */
  89         size_t iie_cmdlen;              /* length of command */
  90         void *iie_buf;                  /* pointer to data buffer */
  91         size_t iie_buflen;              /* length of data buffer */
  92 } i2c_ioctl_exec_t;
  93 #define I2C_EXEC_MAX_CMDLEN     32
  94 #define I2C_EXEC_MAX_BUFLEN     32
  95
  96 #define I2C_IOCTL_EXEC           _IOW('I', 0, i2c_ioctl_exec_t)
  97
  98 #endif /* _DEV_I2C_I2C_IO_H_ */