i2c.h

这是linux内核C源代码58的源程序

/* ------------------------------------------------------------------------- */
/* 									     */
/* 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., 675 Mass Ave, Cambridge, MA 02139, USA.		     */
/* ------------------------------------------------------------------------- */

/* With some changes from Ky鰏ti M鋖kki <[e-mail]> and
   Frodo Looijaard <[e-mail]> */

/* $Id: i2c.h,v 1.2 2001/10/31 16:18:26 arjanv Exp $ */

#ifndef I2C_H
#define I2C_H

#include <linux/i2c-id.h>	/* id values of adapters et. al. 	*/
#include <linux/types.h>


struct i2c_msg;




/*
 * I2C Message - used for pure i2c transaction, also from /dev interface
 */
struct i2c_msg {
	__u16 addr;	/* slave address			*/
	unsigned short flags;		
#define I2C_M_TEN	0x10	/* we have a ten bit chip address	*/
#define I2C_M_RD	0x01
#define I2C_M_NOSTART	0x4000
#define I2C_M_REV_DIR_ADDR	0x2000
	short len;		/* msg length				*/
	char *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_{REV_DIR_ADDR,NOSTART} */
#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 /* New I2C-like block */
#define I2C_FUNC_SMBUS_WRITE_I2C_BLOCK	0x08000000 /* transfer */

#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

/* 
 * Data for SMBus Messages 
 */
union i2c_smbus_data {
	__u8 byte;
	__u16 word;
	__u8 block[33]; /* block[0] is used for length */
};

/* smbus_access 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_DATA    6


/* ----- commands for the ioctl like i2c_command call:
 * note that additional calls are defined in the algorithm and hw 
 *	dependent layers - these can be listed here, or see the 
 *	corresponding header files.
 */
				/* -> bit-adapter specific ioctls	*/
#define I2C_RETRIES	0x0701	/* number times a device address should	*/
				/* be polled when not acknowledging 	*/
#define I2C_TIMEOUT	0x0702	/* set timeout - call with int 		*/


/* this is for i2c-dev.c	*/
#define I2C_SLAVE	0x0703	/* Change slave address			*/
				/* Attn.: Slave address is 7 or 10 bits */
#define I2C_SLAVE_FORCE	0x0706	/* Change slave address			*/
				/* Attn.: Slave address is 7 or 10 bits */
				/* This changes the address, even if it */
				/* is already taken!			*/
#define I2C_TENBIT	0x0704	/* 0 for 7 bit addrs, != 0 for 10 bit	*/

#define I2C_FUNCS	0x0705	/* Get the adapter functionality */
#define I2C_RDWR	0x0707	/* Combined R/W transfer (one stop only)*/
#if 0
#define I2C_ACK_TEST	0x0710	/* See if a slave is at a specific address */
#endif

#define I2C_SMBUS	0x0720	/* SMBus-level access */

/* ... algo-bit.c recognizes */
#define I2C_UDELAY	0x0705	/* set delay in microsecs between each	*/
				/* written byte (except address)	*/
#define I2C_MDELAY	0x0706	/* millisec delay between written bytes */

/* ----- I2C-DEV: char device interface stuff ------------------------- */

#define I2C_MAJOR	89		/* Device major number		*/


#endif /* I2C_H */