Re: [PATCH] dvb: Allow MAC addresses to be mapped to stable device names with udev

[David Howells]

Sean Young <sean@xxxxxxxx> wrote:

> > > Devices without a mac address shouldn't have a mac_dvb sysfs attribute,
> > > I think.
> > 
> > I'm not sure that's possible within the core infrastructure.  It's a class
> > attribute set when the class is created; I'm not sure it can be overridden on
> > a per-device basis.
> > 
> > Possibly the file could return "" or "none" in this case?
> 
> That's very ugly. Have a look at, for example, rc-core wakeup filters:
> 
> https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/drivers/media/rc/rc-main.c#n1844

By analogy, then, I think the thing to do is to put something like struct
rc_dev::sysfs_groups[] into struct dvb_device (or maybe struct dvb_adapter)
and then the dvb_mac attribute in there during dvb_register_device() based on
whether or not the MAC address is not all zeros at that point.

David