i2c: core: Remove definition of i2c_smbus_process_call

i2c_smbus_process_call has no users in the kernel, so this can be
removed. Documentation for the same has been updated accordingly.

Fixes following sparse warning.
drivers/i2c/i2c-core.c:1871:5: warning: symbol 'i2c_smbus_process_call'
was not declared. Should it be static?

[wsa: updated the documentation]
Signed-off-by: Tushar Behera <tushar.behera@linaro.org>
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>

Documentation/i2c/smbus-protocol

@@ -137,8 +137,8 @@ available for writes where the two data bytes are the other way
 around (not SMBus compliant, but very popular.)
 
 
-SMBus Process Call:  i2c_smbus_process_call()
-=============================================
+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.

Documentation/i2c/writing-clients

@@ -365,8 +365,6 @@ in terms of it. Never use this function directly!
 	s32 i2c_smbus_read_word_data(struct i2c_client *client, u8 command);
 	s32 i2c_smbus_write_word_data(struct i2c_client *client,
 				      u8 command, u16 value);
-	s32 i2c_smbus_process_call(struct i2c_client *client,
-				   u8 command, u16 value);
 	s32 i2c_smbus_read_block_data(struct i2c_client *client,
 				      u8 command, u8 *values);
 	s32 i2c_smbus_write_block_data(struct i2c_client *client,
@@ -381,6 +379,8 @@ These ones were removed from i2c-core because they had no users, but could
 be added back later if needed:
 
 	s32 i2c_smbus_write_quick(struct i2c_client *client, u8 value);
+	s32 i2c_smbus_process_call(struct i2c_client *client,
+				   u8 command, u16 value);
 	s32 i2c_smbus_block_process_call(struct i2c_client *client,
 					 u8 command, u8 length, u8 *values);
 

drivers/i2c/i2c-core.c

@@ -1865,29 +1865,6 @@ s32 i2c_smbus_write_word_data(const struct i2c_client *client, u8 command,
 }
 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(const 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