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Diffstat (limited to 'include/linux')
| -rw-r--r-- | include/linux/i2c-dev.h | 334 |
1 files changed, 334 insertions, 0 deletions
diff --git a/include/linux/i2c-dev.h b/include/linux/i2c-dev.h new file mode 100644 index 0000000..2caeaac --- /dev/null +++ b/include/linux/i2c-dev.h @@ -0,0 +1,334 @@ +/* + i2c-dev.h - i2c-bus driver, char device interface + + Copyright (C) 1995-97 Simon G. Vogl + Copyright (C) 1998-99 Frodo Looijaard <frodol@dds.nl> + + 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. +*/ + +/* $Id: i2c-dev.h 5361 2008-10-19 09:47:02Z khali $ */ + +#ifndef LIB_I2CDEV_H +#define LIB_I2CDEV_H + +#include <linux/types.h> +#include <sys/ioctl.h> + + +/* -- i2c.h -- */ + + +/* + * 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 +#define I2C_M_IGNORE_NAK 0x1000 +#define I2C_M_NO_RD_ACK 0x0800 + 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_PEC 0x00000008 +#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) + +/* Old name, for compatibility */ +#define I2C_FUNC_SMBUS_HWPEC_CALC I2C_FUNC_SMBUS_PEC + +/* + * Data for SMBus Messages + */ +#define I2C_SMBUS_BLOCK_MAX 32 /* As specified in SMBus standard */ +#define I2C_SMBUS_I2C_BLOCK_MAX 32 /* Not specified but we use same structure */ +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 PEC */ +}; + +/* 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_BROKEN 6 +#define I2C_SMBUS_BLOCK_PROC_CALL 7 /* SMBus 2.0 */ +#define I2C_SMBUS_I2C_BLOCK_DATA 8 + + +/* ----- 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 of 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)*/ +#define I2C_PEC 0x0708 /* != 0 for SMBus PEC */ + +#define I2C_SMBUS 0x0720 /* SMBus-level access */ + +/* -- i2c.h -- */ + + +/* Note: 10-bit addresses are NOT supported! */ + +/* This is the structure as used in the I2C_SMBUS ioctl call */ +struct i2c_smbus_ioctl_data { + char read_write; + __u8 command; + int size; + union i2c_smbus_data *data; +}; + +/* This is the structure as used in the I2C_RDWR ioctl call */ +struct i2c_rdwr_ioctl_data { + struct i2c_msg *msgs; /* pointers to i2c_msgs */ + int nmsgs; /* number of i2c_msgs */ +}; + + +static inline __s32 i2c_smbus_access(int file, char read_write, __u8 command, + int size, union i2c_smbus_data *data) +{ + struct i2c_smbus_ioctl_data args; + + args.read_write = read_write; + args.command = command; + args.size = size; + args.data = data; + return ioctl(file,I2C_SMBUS,&args); +} + + +static inline __s32 i2c_smbus_write_quick(int file, __u8 value) +{ + return i2c_smbus_access(file,value,0,I2C_SMBUS_QUICK,NULL); +} + +static inline __s32 i2c_smbus_read_byte(int file) +{ + union i2c_smbus_data data; + if (i2c_smbus_access(file,I2C_SMBUS_READ,0,I2C_SMBUS_BYTE,&data)) + return -1; + else + return 0x0FF & data.byte; +} + +static inline __s32 i2c_smbus_write_byte(int file, __u8 value) +{ + return i2c_smbus_access(file,I2C_SMBUS_WRITE,value, + I2C_SMBUS_BYTE,NULL); +} + +static inline __s32 i2c_smbus_read_byte_data(int file, __u8 command) +{ + union i2c_smbus_data data; + if (i2c_smbus_access(file,I2C_SMBUS_READ,command, + I2C_SMBUS_BYTE_DATA,&data)) + return -1; + else + return 0x0FF & data.byte; +} + +static inline __s32 i2c_smbus_write_byte_data(int file, __u8 command, + __u8 value) +{ + union i2c_smbus_data data; + data.byte = value; + return i2c_smbus_access(file,I2C_SMBUS_WRITE,command, + I2C_SMBUS_BYTE_DATA, &data); +} + +static inline __s32 i2c_smbus_read_word_data(int file, __u8 command) +{ + union i2c_smbus_data data; + if (i2c_smbus_access(file,I2C_SMBUS_READ,command, + I2C_SMBUS_WORD_DATA,&data)) + return -1; + else + return 0x0FFFF & data.word; +} + +static inline __s32 i2c_smbus_write_word_data(int file, __u8 command, + __u16 value) +{ + union i2c_smbus_data data; + data.word = value; + return i2c_smbus_access(file,I2C_SMBUS_WRITE,command, + I2C_SMBUS_WORD_DATA, &data); +} + +static inline __s32 i2c_smbus_process_call(int file, __u8 command, __u16 value) +{ + union i2c_smbus_data data; + data.word = value; + if (i2c_smbus_access(file,I2C_SMBUS_WRITE,command, + I2C_SMBUS_PROC_CALL,&data)) + return -1; + else + return 0x0FFFF & data.word; +} + + +/* Returns the number of read bytes */ +static inline __s32 i2c_smbus_read_block_data(int file, __u8 command, + __u8 *values) +{ + union i2c_smbus_data data; + int i; + if (i2c_smbus_access(file,I2C_SMBUS_READ,command, + I2C_SMBUS_BLOCK_DATA,&data)) + return -1; + else { + for (i = 1; i <= data.block[0]; i++) + values[i-1] = data.block[i]; + return data.block[0]; + } +} + +static inline __s32 i2c_smbus_write_block_data(int file, __u8 command, + __u8 length, __u8 *values) +{ + union i2c_smbus_data data; + int i; + if (length > 32) + length = 32; + for (i = 1; i <= length; i++) + data.block[i] = values[i-1]; + data.block[0] = length; + return i2c_smbus_access(file,I2C_SMBUS_WRITE,command, + I2C_SMBUS_BLOCK_DATA, &data); +} + +/* Returns the number of read bytes */ +/* Until kernel 2.6.22, the length is hardcoded to 32 bytes. If you + ask for less than 32 bytes, your code will only work with kernels + 2.6.23 and later. */ +static inline __s32 i2c_smbus_read_i2c_block_data(int file, __u8 command, + __u8 length, __u8 *values) +{ + union i2c_smbus_data data; + int i; + + if (length > 32) + length = 32; + data.block[0] = length; + if (i2c_smbus_access(file,I2C_SMBUS_READ,command, + length == 32 ? I2C_SMBUS_I2C_BLOCK_BROKEN : + I2C_SMBUS_I2C_BLOCK_DATA,&data)) + return -1; + else { + for (i = 1; i <= data.block[0]; i++) + values[i-1] = data.block[i]; + return data.block[0]; + } +} + +static inline __s32 i2c_smbus_write_i2c_block_data(int file, __u8 command, + __u8 length, __u8 *values) +{ + union i2c_smbus_data data; + int i; + if (length > 32) + length = 32; + for (i = 1; i <= length; i++) + data.block[i] = values[i-1]; + data.block[0] = length; + return i2c_smbus_access(file,I2C_SMBUS_WRITE,command, + I2C_SMBUS_I2C_BLOCK_BROKEN, &data); +} + +/* Returns the number of read bytes */ +static inline __s32 i2c_smbus_block_process_call(int file, __u8 command, + __u8 length, __u8 *values) +{ + union i2c_smbus_data data; + int i; + if (length > 32) + length = 32; + for (i = 1; i <= length; i++) + data.block[i] = values[i-1]; + data.block[0] = length; + if (i2c_smbus_access(file,I2C_SMBUS_WRITE,command, + I2C_SMBUS_BLOCK_PROC_CALL,&data)) + return -1; + else { + for (i = 1; i <= data.block[0]; i++) + values[i-1] = data.block[i]; + return data.block[0]; + } +} + + +#endif /* LIB_I2CDEV_H */ |