Re: [PATCH] staging: comedi: register sysfs device attributes with driver core

[Dan Carpenter <dan.carpenter@oracle.com>]

On Fri, May 11, 2012 at 02:14:02PM +0100, Ian Abbott wrote:
> On 2012-05-11 07:16, Dan Carpenter wrote:
> >On Thu, May 10, 2012 at 06:05:28PM -0700, H Hartley Sweeten wrote:
> >>-static const struct attribute_group comedi_sysfs_files = {
> >>-	.attrs	= comedi_attrs,
> >>+static struct device_attribute comedi_dev_attrs[] = {
> >>+	__ATTR(max_read_buffer_kb, S_IRUGO | S_IWUSR,
> >>+		show_max_read_buffer_kb, store_max_read_buffer_kb),
> >>+	__ATTR(read_buffer_kb, S_IRUGO | S_IWUSR | S_IWGRP,
> >>+		show_read_buffer_kb, store_read_buffer_kb),
> >>+	__ATTR(max_write_buffer_kb, S_IRUGO | S_IWUSR,
> >>+		show_max_write_buffer_kb, store_max_write_buffer_kb),
> >>+	__ATTR(write_buffer_kb, S_IRUGO | S_IWUSR | S_IWGRP,
> >>+		show_write_buffer_kb, store_write_buffer_kb),
> >>+	__ATTR_NULL
> >
> >Some of these are group writable and some are only user writable so
> >it's not consistent.  Probably just make them user writeable.
> >
> >I guess this was in the original code too, but it's just more
> >obvious now that they're grouped together.
> 
> Is it possible to change (group) ownership of these attribute files
> using udev rules?  Ideally, users in the group that has group
> ownership on the /dev/comedi* files should be able to modify the
> read_buffer_kb and write_buffer_kb attribute files as well, but only
> super-users should be able to modify the max_read_buffer_kb and
> max_write_buffer_kb files.
> 

Oh.  Ok that's fine then.  I didn't understand what was going on.

regards,
dan carpenter