diff options
Diffstat (limited to 'include/linux/i2c.h')
| -rw-r--r-- | include/linux/i2c.h | 102 |
1 files changed, 49 insertions, 53 deletions
diff --git a/include/linux/i2c.h b/include/linux/i2c.h index 2a32f2fd940..8033e6b3327 100644 --- a/include/linux/i2c.h +++ b/include/linux/i2c.h @@ -35,8 +35,6 @@ #include <linux/sched.h> /* for completion */ #include <linux/mutex.h> -extern struct bus_type i2c_bus_type; - /* --- General options ------------------------------------------------ */ struct i2c_msg; @@ -292,9 +290,6 @@ struct i2c_algorithm { unsigned short flags, char read_write, u8 command, int size, union i2c_smbus_data * data); - /* --- ioctl like call to set div. parameters. */ - int (*algo_control)(struct i2c_adapter *, unsigned int, unsigned long); - /* To determine what the adapter supports */ u32 (*functionality) (struct i2c_adapter *); }; @@ -342,9 +337,10 @@ static inline void i2c_set_adapdata (struct i2c_adapter *dev, void *data) } /*flags for the client struct: */ -#define I2C_CLIENT_PEC 0x04 /* Use Packet Error Checking */ -#define I2C_CLIENT_TEN 0x10 /* we have a ten bit chip address */ - /* Must equal I2C_M_TEN below */ +#define I2C_CLIENT_PEC 0x04 /* Use Packet Error Checking */ +#define I2C_CLIENT_TEN 0x10 /* we have a ten bit chip address */ + /* Must equal I2C_M_TEN below */ +#define I2C_CLIENT_WAKE 0x80 /* for board_info; true iff can wake */ /* i2c adapter classes (bitmask) */ #define I2C_CLASS_HWMON (1<<0) /* lm_sensors, ... */ @@ -417,10 +413,6 @@ extern int i2c_probe(struct i2c_adapter *adapter, struct i2c_client_address_data *address_data, int (*found_proc) (struct i2c_adapter *, int, int)); -/* An ioctl like call to set div. parameters of the adapter. - */ -extern int i2c_control(struct i2c_client *,unsigned int, unsigned long); - extern struct i2c_adapter* i2c_get_adapter(int id); extern void i2c_put_adapter(struct i2c_adapter *adap); @@ -444,19 +436,52 @@ static inline int i2c_adapter_id(struct i2c_adapter *adap) } #endif /* __KERNEL__ */ -/* - * I2C Message - used for pure i2c transaction, also from /dev interface +/** + * 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 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 -#define I2C_M_RECV_LEN 0x0400 /* length will be first received byte */ +#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_NOSTART 0x4000 /* if I2C_FUNC_PROTOCOL_MANGLING */ +#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 */ }; @@ -466,7 +491,7 @@ struct i2c_msg { #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_HWPEC_CALC 0x00000008 /* SMBus 2.0 */ +#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 @@ -502,7 +527,8 @@ struct i2c_msg { I2C_FUNC_SMBUS_WORD_DATA | \ I2C_FUNC_SMBUS_PROC_CALL | \ I2C_FUNC_SMBUS_WRITE_BLOCK_DATA | \ - I2C_FUNC_SMBUS_I2C_BLOCK) + I2C_FUNC_SMBUS_I2C_BLOCK | \ + I2C_FUNC_SMBUS_PEC) /* * Data for SMBus Messages @@ -532,38 +558,8 @@ union i2c_smbus_data { #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-DEV: char device interface stuff ------------------------- */ #ifdef __KERNEL__ -#define I2C_MAJOR 89 /* Device major number */ - /* These defines are used for probing i2c client addresses */ /* The length of the option lists */ #define I2C_CLIENT_MAX_OPTS 48 |