i2c: Restore i2c_smbus_process_call function

Restore the i2c_smbus_process_call() as one driver (for the
Micronas MAP5401) will need it soon.

[JD: Update documentation accordingly.]

Signed-off-by: Prakash Mortha <pmortha@escient.com>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
This commit is contained in:
Prakash Mortha 2008-10-14 17:30:06 +02:00 committed by Jean Delvare
parent a10f9e7caf
commit 596c88f460
3 changed files with 26 additions and 4 deletions

View file

@ -109,8 +109,8 @@ specified through the Comm byte.
S Addr Wr [A] Comm [A] DataLow [A] DataHigh [A] P
SMBus Process Call
==================
SMBus Process Call: i2c_smbus_process_call()
=============================================
This command selects a device register (through the Comm byte), sends
16 bits of data to it, and reads 16 bits of data in return.

View file

@ -606,6 +606,8 @@ SMBus communication
extern s32 i2c_smbus_read_word_data(struct i2c_client * client, u8 command);
extern s32 i2c_smbus_write_word_data(struct i2c_client * client,
u8 command, u16 value);
extern s32 i2c_smbus_process_call(struct i2c_client *client,
u8 command, u16 value);
extern s32 i2c_smbus_read_block_data(struct i2c_client * client,
u8 command, u8 *values);
extern s32 i2c_smbus_write_block_data(struct i2c_client * client,
@ -621,8 +623,6 @@ These ones were removed from i2c-core because they had no users, but could
be added back later if needed:
extern s32 i2c_smbus_write_quick(struct i2c_client * client, u8 value);
extern s32 i2c_smbus_process_call(struct i2c_client * client,
u8 command, u16 value);
extern s32 i2c_smbus_block_process_call(struct i2c_client *client,
u8 command, u8 length,
u8 *values)

View file

@ -1687,6 +1687,28 @@ s32 i2c_smbus_write_word_data(struct i2c_client *client, u8 command, u16 value)
}
EXPORT_SYMBOL(i2c_smbus_write_word_data);
/**
* i2c_smbus_process_call - SMBus "process call" protocol
* @client: Handle to slave device
* @command: Byte interpreted by slave
* @value: 16-bit "word" being written
*
* This executes the SMBus "process call" protocol, returning negative errno
* else a 16-bit unsigned "word" received from the device.
*/
s32 i2c_smbus_process_call(struct i2c_client *client, u8 command, u16 value)
{
union i2c_smbus_data data;
int status;
data.word = value;
status = i2c_smbus_xfer(client->adapter, client->addr, client->flags,
I2C_SMBUS_WRITE, command,
I2C_SMBUS_PROC_CALL, &data);
return (status < 0) ? status : data.word;
}
EXPORT_SYMBOL(i2c_smbus_process_call);
/**
* i2c_smbus_read_block_data - SMBus "block read" protocol
* @client: Handle to slave device