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>

1 files changed, 22 insertions, 0 deletions

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