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