On 2023-01-18 16:19:20, Jonathan Cameron wrote: > On Mon, 16 Jan 2023 23:09:05 +0100 > Marijn Suijten <marijn.suijten@xxxxxxxxxxxxxx> wrote: > > > As mentioned and discussed in [1] extend_name should not be used for > > full channel labels (and most drivers seem to only use it to express a > > short type of a channel) as this affects sysfs filenames, while the > > label name is supposed to be extracted from the *_label sysfs file > > instead. This appears to have been unclear to some drivers as > > extend_name is also used when read_label is unset, achieving an initial > > goal of providing sensible names in *_label sysfs files without noticing > > that sysfs filenames are (negatively and likely unintentionally) > > affected as well. > > > > Point readers of iio_chan_spec::extend_name to iio_info::read_label by > > mentioning deprecation and side-effects of this field. > > > > [1]: https://lore.kernel.org/linux-arm-msm/20221221223432.si2aasbleiicayfl@xxxxxxxxxxxxxx/ > > > > Suggested-by: Jonathan Cameron <jic23@xxxxxxxxxx> > > Signed-off-by: Marijn Suijten <marijn.suijten@xxxxxxxxxxxxxx> > > --- > > include/linux/iio/iio.h | 3 +++ > > 1 file changed, 3 insertions(+) > > > > diff --git a/include/linux/iio/iio.h b/include/linux/iio/iio.h > > index 81413cd3a3e7..36c89f238fb9 100644 > > --- a/include/linux/iio/iio.h > > +++ b/include/linux/iio/iio.h > > @@ -221,6 +221,9 @@ struct iio_event_spec { > > * @extend_name: Allows labeling of channel attributes with an > > * informative name. Note this has no effect codes etc, > > * unlike modifiers. > > + * This field is deprecated in favour of overriding read_label > > + * in iio_info, which unlike @extend_name does not affect sysfs > > + * filenames. > Perhaps reword as > > This field is deprecated in favour of overriding the default label > by providing a read_label() callback in iio_info, which unlike > @extend_name does not affect sysfs filenames. > ? Agreed, explicitly stating "the default label by" makes this much more clear. Though, maybe swap that around into "in favour of providing read_label() in iio_info to override the label"? Otherwise this could be interpreted as "overriding the default label" is preferred to setting extend_name... which one would do to override the default label. I can queue this up for v3 unless you'll fix it up while applying, presuming no other changes have to be made (aside from dropping patch 3/5). Will read_label() turn into a link? And is the @extend_name reference proper? Is there something to link to iio_info, perhaps a hashtag - or maybe fully qualify `#iio_info::read_label()` for linking purposes? /me jumps over to kerneldoc documentation :) - Marijn > > * @datasheet_name: A name used in in-kernel mapping of channels. It should > > * correspond to the first name that the channel is referred > > * to by in the datasheet (e.g. IND), or the nearest >
