i2c: Functions for byte-swapped smbus_write/read_word_data

Reimplemented at least 17 times discounting error mangling cases
where it could be used.

Signed-off-by: Jonathan Cameron <jic23@cam.ac.uk>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
diff --git a/Documentation/i2c/smbus-protocol b/Documentation/i2c/smbus-protocol
index 7c19d1a..49f5b68 100644
--- a/Documentation/i2c/smbus-protocol
+++ b/Documentation/i2c/smbus-protocol
@@ -88,6 +88,10 @@
 
 S Addr Wr [A] Comm [A] S Addr Rd [A] [DataLow] A [DataHigh] NA P
 
+Note the convenience function i2c_smbus_read_word_swapped is
+available for reads where the two data bytes are the other way
+around (not SMBus compliant, but very popular.)
+
 
 SMBus Write Byte:  i2c_smbus_write_byte_data()
 ==============================================
@@ -108,6 +112,10 @@
 
 S Addr Wr [A] Comm [A] DataLow [A] DataHigh [A] P
 
+Note the convenience function i2c_smbus_write_word_swapped is
+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()
 =============================================