V2: Jean's suggestions: 1) Documentation as comments on the smbus_write_word_data and smbus_read_word_data entries in Documetation/i2c/smbus-protocol 2) /* for swab 16 comment */ 3) shorter names for the two functions (drop the _data part as it doesn't tell us anything anyway). V1: Hi All, Quite a number of devices rather unhelpfully handle smbus read/write word commands but return the result byte swapped. Hence drivers swap it back again. Examples based on quick grep or read users that byte swap(write is completely trivial) drivers/hwmon/ad7418.c - no error handling so trivial drivers/hwmon/ads1015.c - correct drivers/hwmon/asb100.c - no error handling so trivial drivers/hwmon/ds1621.c - correct drivers/hwmon/ds620.c - no error handling so trivial drivers/hwmon/gl518sm.c - no error handling so trivial drivers/hwmon/gl520sm.c - no error handling so trivial drivers/hwmon/jc42.c - correct drivers/hwmon/lm73.c - no error handling drivers/hwmon/lm75.c - correct drivers/hwmon/lm92.c - some are byte swapped. Implementation doesn't handle errors drivers/hwmon/tmp102.c - correct drivers/hwmon/w83781.c - no error handling. drivers/input/touchscreen/ad7879-i2c.c - no error handling drivers/media/video/mt9m001.c - correct drivers/media/video/mt9m111.c - no error handling drivers/media/video/mt9t031.c - correct drivers/media/video/mt9v022.c - correct drivers/media/video/mt9v032.c - correct drivers/media/video/vpx3220.c - correct drivers/staging/iio/adc/ad7150.c - correct drivers/staging/iio/adc/ad7152.c - correct drivers/staging/iio/adc/ad7291.c - correct drivers/staging/iio/adc/ad7746.c - correct drivers/staging/iio/adc/ad799x_core.c - correct drivers/staging/iio/adc/adt7410.c - correct drivers/staging/iio/adc/adt75.c - correct 'correct' are those that need handle or at least pass on the error code without mangling it. The others typically just shove an error into some local cache without taking any notice. Just for the curious this is based on greping for i2c_smbus_write_word_data and looking to see if the read does the swab16 as well. Anyhow, so to the proposal. Introduce a couple of inline static functions into i2c.h. My only use examples done so far are on top of unpublished iio changes, so I'll leave the reader to take a look and decided whether or not this is interesting enough to do. Even if the driver uses equivalent functions we are saving about 6 lines per user. I'm happy to do a series converting the easy ones from the above if people don't mind the patch. Jonathan Cameron (1): i2c: boilerplate function for byte swapped smbus_write/read_word_data Documentation/i2c/smbus-protocol | 8 ++++++++ include/linux/i2c.h | 17 +++++++++++++++++ 2 files changed, 25 insertions(+), 0 deletions(-) -- 1.7.3.4 -- To unsubscribe from this list: send the line "unsubscribe linux-i2c" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
