i2c.h

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/* ------------------------------------------------------------------------- */
/*                                       */
/* i2c.h - definitions for the i2c-bus interface                 */
/*                                       */
/* ------------------------------------------------------------------------- */
/*   Copyright (C) 1995-2000 Simon G. Vogl

    This program 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 2 of the License, or
    (at your option) any later version.

    This program 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, write to the Free Software
    Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
    MA 02110-1301 USA.                               */
/* ------------------------------------------------------------------------- */

/* With some changes from Kyösti Mälkki <[email protected]> and
   Frodo Looijaard <[email protected]> */

#ifndef _UAPI_LINUX_I2C_H
#define _UAPI_LINUX_I2C_H

#include <linux/types.h>

struct i2c_msg {
    __u16 addr; /* slave address            */
    __u16 flags;
#define I2C_M_TEN       0x0010  /* this is a ten bit chip address */
#define I2C_M_RD        0x0001  /* read data, from slave to master */
#define I2C_M_STOP      0x8000  /* if I2C_FUNC_PROTOCOL_MANGLING */
#define I2C_M_NOSTART       0x4000  /* if I2C_FUNC_NOSTART */
#define I2C_M_REV_DIR_ADDR  0x2000  /* if I2C_FUNC_PROTOCOL_MANGLING */
#define I2C_M_IGNORE_NAK    0x1000  /* if I2C_FUNC_PROTOCOL_MANGLING */
#define I2C_M_NO_RD_ACK     0x0800  /* if I2C_FUNC_PROTOCOL_MANGLING */
#define I2C_M_RECV_LEN      0x0400  /* length will be first received byte */
    __u16 len;      /* msg length               */
    __u8 *buf;      /* pointer to msg data          */
};

/* To determine what functionality is present */

#define I2C_FUNC_I2C            0x00000001
#define I2C_FUNC_10BIT_ADDR     0x00000002
#define I2C_FUNC_PROTOCOL_MANGLING  0x00000004 /* I2C_M_IGNORE_NAK etc. */
#define I2C_FUNC_SMBUS_PEC      0x00000008
#define I2C_FUNC_NOSTART        0x00000010 /* I2C_M_NOSTART */
#define I2C_FUNC_SMBUS_BLOCK_PROC_CALL  0x00008000 /* SMBus 2.0 */
#define I2C_FUNC_SMBUS_QUICK        0x00010000
#define I2C_FUNC_SMBUS_READ_BYTE    0x00020000
#define I2C_FUNC_SMBUS_WRITE_BYTE   0x00040000
#define I2C_FUNC_SMBUS_READ_BYTE_DATA   0x00080000
#define I2C_FUNC_SMBUS_WRITE_BYTE_DATA  0x00100000
#define I2C_FUNC_SMBUS_READ_WORD_DATA   0x00200000
#define I2C_FUNC_SMBUS_WRITE_WORD_DATA  0x00400000
#define I2C_FUNC_SMBUS_PROC_CALL    0x00800000
#define I2C_FUNC_SMBUS_READ_BLOCK_DATA  0x01000000
#define I2C_FUNC_SMBUS_WRITE_BLOCK_DATA 0x02000000
#define I2C_FUNC_SMBUS_READ_I2C_BLOCK   0x04000000 /* I2C-like block xfer  */
#define I2C_FUNC_SMBUS_WRITE_I2C_BLOCK  0x08000000 /* w/ 1-byte reg. addr. */

#define I2C_FUNC_SMBUS_BYTE     (I2C_FUNC_SMBUS_READ_BYTE | \
                     I2C_FUNC_SMBUS_WRITE_BYTE)
#define I2C_FUNC_SMBUS_BYTE_DATA    (I2C_FUNC_SMBUS_READ_BYTE_DATA | \
                     I2C_FUNC_SMBUS_WRITE_BYTE_DATA)
#define I2C_FUNC_SMBUS_WORD_DATA    (I2C_FUNC_SMBUS_READ_WORD_DATA | \
                     I2C_FUNC_SMBUS_WRITE_WORD_DATA)
#define I2C_FUNC_SMBUS_BLOCK_DATA   (I2C_FUNC_SMBUS_READ_BLOCK_DATA | \
                     I2C_FUNC_SMBUS_WRITE_BLOCK_DATA)
#define I2C_FUNC_SMBUS_I2C_BLOCK    (I2C_FUNC_SMBUS_READ_I2C_BLOCK | \
                     I2C_FUNC_SMBUS_WRITE_I2C_BLOCK)

#define I2C_FUNC_SMBUS_EMUL     (I2C_FUNC_SMBUS_QUICK | \
                     I2C_FUNC_SMBUS_BYTE | \
                     I2C_FUNC_SMBUS_BYTE_DATA | \
                     I2C_FUNC_SMBUS_WORD_DATA | \
                     I2C_FUNC_SMBUS_PROC_CALL | \
                     I2C_FUNC_SMBUS_WRITE_BLOCK_DATA | \
                     I2C_FUNC_SMBUS_I2C_BLOCK | \
                     I2C_FUNC_SMBUS_PEC)

/*
 * Data for SMBus Messages
 */
#define I2C_SMBUS_BLOCK_MAX 32  /* As specified in SMBus standard */
union i2c_smbus_data {
    __u8 byte;
    __u16 word;
    __u8 block[I2C_SMBUS_BLOCK_MAX + 2]; /* block[0] is used for length */
                   /* and one more for user-space compatibility */
};

/* i2c_smbus_xfer read or write markers */
#define I2C_SMBUS_READ  1
#define I2C_SMBUS_WRITE 0

/* SMBus transaction types (size parameter in the above functions)
   Note: these no longer correspond to the (arbitrary) PIIX4 internal codes! */
#define I2C_SMBUS_QUICK         0
#define I2C_SMBUS_BYTE          1
#define I2C_SMBUS_BYTE_DATA     2
#define I2C_SMBUS_WORD_DATA     3
#define I2C_SMBUS_PROC_CALL     4
#define I2C_SMBUS_BLOCK_DATA        5
#define I2C_SMBUS_I2C_BLOCK_BROKEN  6
#define I2C_SMBUS_BLOCK_PROC_CALL   7       /* SMBus 2.0 */
#define I2C_SMBUS_I2C_BLOCK_DATA    8

#endif /* _UAPI_LINUX_I2C_H */