At first: Thanks for your review! On Monday 25 February 2013 at 05:00:25, Greg KH wrote: > On Tue, Feb 19, 2013 at 03:27:41PM +0100, Lars Poeschel wrote: > > +static int pwmchip_export(struct pwm_chip *chip) > > +{ > > + int status; > > + struct device *dev; > > + > > + mutex_lock(&sysfs_lock); > > + dev = device_create(&pwm_class, chip->dev, MKDEV(0, 0), chip, > > + "pwmchip%d", chip->base); > > + if (!IS_ERR(dev)) > > + status = sysfs_create_group(&dev->kobj, &pwmchip_attr_group); > > + else > > + status = PTR_ERR(dev); > > You can't create sysfs files after the device has been exposed to > userspace. Please use the default group functionality for the class, > which fixes this problem. I don't understand, what is wrong here. This is the same that gpio sysfs does. Could you please be a bit more specific ? I create a new device using device_create and create a new group with it with some attributes. Isn't it exposed to userspace after that ? Or am I not allowed to use pwm_class on device creation ? What to use then ? What do you mean by default group functionality for the class ? I want to use my own "pwm" class ? Don't I ? Regards, Lars -- To unsubscribe from this list: send the line "unsubscribe linux-doc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html