Re: [RFC PATCH 3/5] hwmon: (ds1621) Convert to use hwmon_device_register_groups

[Jean Delvare <khali@linux-fr.org>]

On Sat, 6 Jul 2013 10:57:47 -0700, Greg Kroah-Hartman wrote:
> On Sat, Jul 06, 2013 at 10:24:53AM -0700, Guenter Roeck wrote:
> > Signed-off-by: Guenter Roeck <linux@roeck-us.net>
> > ---
> >  drivers/hwmon/ds1621.c |   25 +++++++++----------------
> >  1 file changed, 9 insertions(+), 16 deletions(-)
> > 
> > diff --git a/drivers/hwmon/ds1621.c b/drivers/hwmon/ds1621.c
> > index a26ba7a..f1d0fa0 100644
> > --- a/drivers/hwmon/ds1621.c
> > +++ b/drivers/hwmon/ds1621.c
> > @@ -358,11 +358,15 @@ static const struct attribute_group ds1621_group = {
> >  	.is_visible = ds1621_attribute_visible
> >  };
> >  
> > +static const struct attribute_group *ds1621_groups[] = {
> > +	&ds1621_group,
> > +	NULL
> > +};
> > +
> >  static int ds1621_probe(struct i2c_client *client,
> >  			const struct i2c_device_id *id)
> >  {
> >  	struct ds1621_data *data;
> > -	int err;
> >  
> >  	data = devm_kzalloc(&client->dev, sizeof(struct ds1621_data),
> >  			    GFP_KERNEL);
> > @@ -377,22 +381,12 @@ static int ds1621_probe(struct i2c_client *client,
> >  	/* Initialize the DS1621 chip */
> >  	ds1621_init_client(client);
> >  
> > -	/* Register sysfs hooks */
> > -	err = sysfs_create_group(&client->dev.kobj, &ds1621_group);
> > -	if (err)
> > -		return err;
> > -
> > -	data->hwmon_dev = hwmon_device_register(&client->dev);
> > -	if (IS_ERR(data->hwmon_dev)) {
> > -		err = PTR_ERR(data->hwmon_dev);
> > -		goto exit_remove_files;
> > -	}
> > +	data->hwmon_dev = hwmon_device_register_groups(&client->dev, data,
> > +						       ds1621_groups);
> > +	if (IS_ERR(data->hwmon_dev))
> > +		return PTR_ERR(data->hwmon_dev);
> >  
> >  	return 0;
> > -
> > - exit_remove_files:
> > -	sysfs_remove_group(&client->dev.kobj, &ds1621_group);
> > -	return err;
> 
> Aren't your sysfs files now being created attached to a different device
> than they originally were?  Before this patch, they were being attached
> to the parent device of the hwmon device being created with the call to
> hwmon_device_register(), and now they are attached to the device created
> with that call.
> 
> Is that what you really want?  Can userspace handle this movement of
> files?

libsensors supports both, as well as pwmconfig/fancontrol. Some drivers
are already doing that so every application dealing with hwmon devices
should handle it already.

-- 
Jean Delvare