Re: [PATCH v2 2/2] iio: core: Add optional symbolic label to device attributes

[Jonathan Cameron <jic23@kernel.org>]

On Sat, 5 Oct 2019 15:59:05 +0100
Jonathan Cameron <jic23@kernel.org> wrote:

> On Thu, 19 Sep 2019 22:36:08 +0800
> Phil Reid <preid@electromag.com.au> wrote:
> 
> > If a label is defined in the device tree for this device add that
> > to the device specific attributes. This is useful for userspace to
> > be able to identify an individual device when multiple identical
> > chips are present in the system.
> > 
> > Tested-by: Michal Simek <michal.simek@xilinx.com>
> > Signed-off-by: Phil Reid <preid@electromag.com.au>  
> 
> Glad to see this going in given I thought I'd already applied it
> and told someone they should be using it early today (oops ;)
> 
> Applied to the togreg branch of iio.git and pushed out as testing
> for the autobuilders to play with it.

0-day picked up that there were no docs for this new field.
I've added some and re pushed out.

Thanks,

Jonathan

> 
> Thanks for doing this.
> 
> Jonathan
> 
> > ---
> >  drivers/iio/industrialio-core.c | 17 +++++++++++++++++
> >  include/linux/iio/iio.h         |  1 +
> >  2 files changed, 18 insertions(+)
> > 
> > diff --git a/drivers/iio/industrialio-core.c b/drivers/iio/industrialio-core.c
> > index 524a686077ca..f72c2dc5f703 100644
> > --- a/drivers/iio/industrialio-core.c
> > +++ b/drivers/iio/industrialio-core.c
> > @@ -1238,6 +1238,16 @@ static ssize_t iio_show_dev_name(struct device *dev,
> >  
> >  static DEVICE_ATTR(name, S_IRUGO, iio_show_dev_name, NULL);
> >  
> > +static ssize_t iio_show_dev_label(struct device *dev,
> > +				 struct device_attribute *attr,
> > +				 char *buf)
> > +{
> > +	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
> > +	return snprintf(buf, PAGE_SIZE, "%s\n", indio_dev->label);
> > +}
> > +
> > +static DEVICE_ATTR(label, S_IRUGO, iio_show_dev_label, NULL);
> > +
> >  static ssize_t iio_show_timestamp_clock(struct device *dev,
> >  					struct device_attribute *attr,
> >  					char *buf)
> > @@ -1354,6 +1364,8 @@ static int iio_device_register_sysfs(struct iio_dev *indio_dev)
> >  
> >  	if (indio_dev->name)
> >  		attrcount++;
> > +	if (indio_dev->label)
> > +		attrcount++;
> >  	if (clk)
> >  		attrcount++;
> >  
> > @@ -1376,6 +1388,8 @@ static int iio_device_register_sysfs(struct iio_dev *indio_dev)
> >  		indio_dev->chan_attr_group.attrs[attrn++] = &p->dev_attr.attr;
> >  	if (indio_dev->name)
> >  		indio_dev->chan_attr_group.attrs[attrn++] = &dev_attr_name.attr;
> > +	if (indio_dev->label)
> > +		indio_dev->chan_attr_group.attrs[attrn++] = &dev_attr_label.attr;
> >  	if (clk)
> >  		indio_dev->chan_attr_group.attrs[attrn++] = clk;
> >  
> > @@ -1647,6 +1661,9 @@ int __iio_device_register(struct iio_dev *indio_dev, struct module *this_mod)
> >  	if (!indio_dev->dev.of_node && indio_dev->dev.parent)
> >  		indio_dev->dev.of_node = indio_dev->dev.parent->of_node;
> >  
> > +	indio_dev->label = of_get_property(indio_dev->dev.of_node, "label",
> > +					   NULL);
> > +
> >  	ret = iio_check_unique_scan_index(indio_dev);
> >  	if (ret < 0)
> >  		return ret;
> > diff --git a/include/linux/iio/iio.h b/include/linux/iio/iio.h
> > index 8e132cf819e4..a2527c7ab934 100644
> > --- a/include/linux/iio/iio.h
> > +++ b/include/linux/iio/iio.h
> > @@ -553,6 +553,7 @@ struct iio_dev {
> >  	struct list_head		channel_attr_list;
> >  	struct attribute_group		chan_attr_group;
> >  	const char			*name;
> > +	const char			*label;
> >  	const struct iio_info		*info;
> >  	clockid_t			clock_id;
> >  	struct mutex			info_exist_lock;  
>