On Sat, 2021-03-20 at 13:52 +0100, Lars-Peter Clausen wrote: > On 3/20/21 12:01 PM, Joe Perches wrote: > > On Sat, 2021-03-20 at 08:14 +0100, Lars-Peter Clausen wrote: > > > Update DAC drivers powerdown attribute show callback to use the new > > > sysfs_emit() function. > > > > > > sysfs_emit() is preferred over raw s*printf() for sysfs attributes since it > > > knows about the sysfs buffer specifics and has some built-in sanity checks. > > Thanks. > > > > unrelated trivia: > > > > > diff --git a/drivers/iio/dac/ad5360.c b/drivers/iio/dac/ad5360.c > > [] > > > @@ -255,7 +255,7 @@ static ssize_t ad5360_read_dac_powerdown(struct device *dev, > > > struct iio_dev *indio_dev = dev_to_iio_dev(dev); > > > struct ad5360_state *st = iio_priv(indio_dev); > > > > > > > > > - return sprintf(buf, "%d\n", (bool)(st->ctrl & AD5360_SF_CTRL_PWR_DOWN)); > > > + return sysfs_emit(buf, "%d\n", (bool)(st->ctrl & AD5360_SF_CTRL_PWR_DOWN)); > > rather than cast to bool, perhaps standardize to use !!(val & test) > I very much prefer the cast to bool since it semantically stronger. You > don't have to know that the !! idiom is used to cast an int to bool. Using !! does not cast to bool, it's an int. casting to bool and using %d in a printf equivalent ends up with an integer promotion/implicit type conversion from bool to int. Anyway, it's not my code so it's author's choice, but similar code using different styles is, at a minimum, inconsistent.
