diff options
| -rw-r--r-- | Documentation/i2c/smbus-protocol | 4 | ||||
| -rw-r--r-- | Documentation/i2c/writing-clients | 4 | ||||
| -rw-r--r-- | drivers/i2c/i2c-core.c | 22 |
3 files changed, 26 insertions, 4 deletions
diff --git a/Documentation/i2c/smbus-protocol b/Documentation/i2c/smbus-protocol index 24bfb65da17d..9df47441f0e7 100644 --- a/Documentation/i2c/smbus-protocol +++ b/Documentation/i2c/smbus-protocol @@ -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. diff --git a/Documentation/i2c/writing-clients b/Documentation/i2c/writing-clients index 6b61b3a2e90b..d73ee117a8ca 100644 --- a/Documentation/i2c/writing-clients +++ b/Documentation/i2c/writing-clients @@ -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) diff --git a/drivers/i2c/i2c-core.c b/drivers/i2c/i2c-core.c index 80ae12048e85..42e852d79ffa 100644 --- a/drivers/i2c/i2c-core.c +++ b/drivers/i2c/i2c-core.c @@ -1688,6 +1688,28 @@ 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 * @command: Byte interpreted by slave |