On Fri, Oct 21, 2011 at 05:14:45PM +0100, Jonathan Cameron wrote: > On 10/21/11 17:09, Dmitry Torokhov wrote: > > On Fri, Oct 21, 2011 at 12:57:16PM +0100, Jonathan Cameron wrote: > >> This varient was introduced in > >> i2c: boilerplate function for byte swapped smbus_write/read_word_data > >> > >> This also has the side effect of ensuring any errors from the i2c > >> read and no longer mangled. > >> > >> Signed-off-by: Jonathan Cameron <[email protected]> > >> --- > >> V2: include the write function as pointed out by Michael Hennerich. > >> > >> The patch introducing this swapped function is working its way through the > >> i2c > >> tree. > >> > >> drivers/input/touchscreen/ad7879-i2c.c | 4 ++-- > >> 1 files changed, 2 insertions(+), 2 deletions(-) > >> > >> diff --git a/drivers/input/touchscreen/ad7879-i2c.c > >> b/drivers/input/touchscreen/ad7879-i2c.c > >> index 4e4e58c..cc51392 100644 > >> --- a/drivers/input/touchscreen/ad7879-i2c.c > >> +++ b/drivers/input/touchscreen/ad7879-i2c.c > >> @@ -47,7 +47,7 @@ static int ad7879_i2c_read(struct device *dev, u8 reg) > >> { > >> struct i2c_client *client = to_i2c_client(dev); > >> > >> - return swab16(i2c_smbus_read_word_data(client, reg)); > >> + return i2c_smbus_read_word_swapped(client, reg); > > > > This is still not endian-safe. I wonder if introducing > > i2c_smbus_read_word_swapped() just makes the metter worse by hiding > > this... > > > > I'd prefer if we had i2c_smbus_read_be16() instead. > smbus spec says that all transfers must be little endian. > Hence it is type safe because the smbus controllers are guaranteed to have > made > that assumption and converted to cpu endianess. If not they are buggy. > Hence, this is endian safe.
Ah, right... OK then. -- Dmitry -- To unsubscribe from this list: send the line "unsubscribe linux-i2c" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
