text: /*
      smbus.h - SMBus level access helper functions
  
      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.
  */
  
  #ifndef LIB_I2C_SMBUS_H
  #define LIB_I2C_SMBUS_H
  
  #include <linux/types.h>
  #include <linux/i2c.h>
  
  extern __s32 i2c_smbus_access(int file, char read_write, __u8 command,
  			      int size, union i2c_smbus_data *data);
  
  extern __s32 i2c_smbus_write_quick(int file, __u8 value);
  extern __s32 i2c_smbus_read_byte(int file);
  extern __s32 i2c_smbus_write_byte(int file, __u8 value);
  extern __s32 i2c_smbus_read_byte_data(int file, __u8 command);
  extern __s32 i2c_smbus_write_byte_data(int file, __u8 command, __u8 value);
  extern __s32 i2c_smbus_read_word_data(int file, __u8 command);
  extern __s32 i2c_smbus_write_word_data(int file, __u8 command, __u16 value);
  extern __s32 i2c_smbus_process_call(int file, __u8 command, __u16 value);
  
  /* Returns the number of read bytes */
  extern __s32 i2c_smbus_read_block_data(int file, __u8 command, __u8 *values);
  extern __s32 i2c_smbus_write_block_data(int file, __u8 command, __u8 length,
  					const __u8 *values);
  
  /* 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. */
  extern __s32 i2c_smbus_read_i2c_block_data(int file, __u8 command, __u8 length,
  					   __u8 *values);
  extern __s32 i2c_smbus_write_i2c_block_data(int file, __u8 command, __u8 length,
  					    const __u8 *values);
  
  /* Returns the number of read bytes */
  extern __s32 i2c_smbus_block_process_call(int file, __u8 command, __u8 length,
  					  __u8 *values);
  
  #endif /* LIB_I2C_SMBUS_H */
  