include/asm-cris/etraxi2c.h

   1 /* $Id: etraxi2c.h,v 1.1 2001/01/18 15:49:57 bjornw Exp $ */
   2
   3 #ifndef _LINUX_ETRAXI2C_H
   4 #define _LINUX_ETRAXI2C_H
   5
   6 /* etraxi2c _IOC_TYPE, bits 8 to 15 in ioctl cmd */
   7
   8 #define ETRAXI2C_IOCTYPE 44
   9
  10 /* supported ioctl _IOC_NR's */
  11
  12 /* in write operations, the argument contains both i2c
  13  * slave, register and value.
  14  */
  15
  16 #define I2C_WRITEARG(slave, reg, value) (((slave) << 16) | ((reg) << 8) | (value))
  17 #define I2C_READARG(slave, reg) (((slave) << 16) | ((reg) << 8))
  18
  19 #define I2C_ARGSLAVE(arg) ((arg) >> 16)
  20 #define I2C_ARGREG(arg) (((arg) >> 8) & 0xff)
  21 #define I2C_ARGVALUE(arg) ((arg) & 0xff)
  22
  23 #define I2C_WRITEREG 0x1   /* write to an i2c register */
  24 #define I2C_READREG  0x2   /* read from an i2c register */
  25
  26 /*
  27 EXAMPLE usage:
  28
  29     i2c_arg = I2C_WRITEARG(STA013_WRITE_ADDR, reg, val);
  30     ioctl(fd, _IO(ETRAXI2C_IOCTYPE, I2C_WRITEREG), i2c_arg);
  31
  32     i2c_arg = I2C_READARG(STA013_READ_ADDR, reg);
  33     val = ioctl(fd, _IO(ETRAXI2C_IOCTYPE, I2C_READREG), i2c_arg);
  34
  35 */
  36 #endif