/* ------------------------------------------------------------------------- *//*									     *//* 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 <kmalkki@cc.hut.fi> and   Frodo Looijaard <frodol@dds.nl> */ #ifndef _UAPI_LINUX_I2C_H#define _UAPI_LINUX_I2C_H #include <linux/types.h> /** * struct i2c_msg - an I2C transaction segment beginning with START * @addr: Slave address, either seven or ten bits.  When this is a ten *	bit address, I2C_M_TEN must be set in @flags and the adapter *	must support I2C_FUNC_10BIT_ADDR. * @flags: I2C_M_RD is handled by all adapters.  No other flags may be *	provided unless the adapter exported the relevant I2C_FUNC_* *	flags through i2c_check_functionality(). * @len: Number of data bytes in @buf being read from or written to the *	I2C slave address.  For read transactions where I2C_M_RECV_LEN *	is set, the caller guarantees that this buffer can hold up to *	32 bytes in addition to the initial length byte sent by the *	slave (plus, if used, the SMBus PEC); and this value will be *	incremented by the number of block data bytes received. * @buf: The buffer into which data is read, or from which it's written. * * An i2c_msg is the low level representation of one segment of an I2C * transaction.  It is visible to drivers in the @i2c_transfer() procedure, * to userspace from i2c-dev, and to I2C adapter drivers through the * @i2c_adapter.@master_xfer() method. * * Except when I2C "protocol mangling" is used, all I2C adapters implement * the standard rules for I2C transactions.  Each transaction begins with a * START.  That is followed by the slave address, and a bit encoding read * versus write.  Then follow all the data bytes, possibly including a byte * with SMBus PEC.  The transfer terminates with a NAK, or when all those * bytes have been transferred and ACKed.  If this is the last message in a * group, it is followed by a STOP.  Otherwise it is followed by the next * @i2c_msg transaction segment, beginning with a (repeated) START. * * Alternatively, when the adapter supports I2C_FUNC_PROTOCOL_MANGLING then * passing certain @flags may have changed those standard protocol behaviors. * Those flags are only for use with broken/nonconforming slaves, and with * adapters which are known to support the specific mangling options they * need (one or more of IGNORE_NAK, NO_RD_ACK, NOSTART, and REV_DIR_ADDR). */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 */