1 files changed, 2 insertions, 0 deletions

diff --git a/include/linux/i2c.h b/include/linux/i2c.h
index 526ddc8eecfb..eb0628a7ecc6 100644
--- a/include/linux/i2c.h
+++ b/include/linux/i2c.h
@@ -193,6 +193,8 @@ struct i2c_algorithm {
            to NULL. If an adapter algorithm can do SMBus access, set 
            smbus_xfer. If set to NULL, the SMBus protocol is simulated
            using common I2C messages */
+        /* master_xfer should return the number of messages successfully
+           processed, or a negative value on error */
         int (*master_xfer)(struct i2c_adapter *adap,struct i2c_msg *msgs, 
                            int num);
         int (*smbus_xfer) (struct i2c_adapter *adap, u16 addr,