How does rfkill work?

[Larry Finger <Larry.Finger@lwfinger.net>]

Johannes,

I'm having trouble getting the radio LED to work on b43legacy. When the LED's
are registered, I get LED index 0 registered with names of "b43legacy-phy0::tx"
and "b43legacy-phy0::rx", and LED index 1 with a name as of
"b43legacy-phy0::radio". I placed printk's at the entrance to
b43legacy_led_brightness_set(), which is the callback routine. I see a number of
calls to modify LED index 0, which I assume are due to RX/TX activity, but only
a single call for LED index 1 when the LED's are still being registered. There
are no such calls generated when the radio switch is moved.

I don't see where/how a particular LED is attached to the rfkill event. Could
you point me to some code that does that?

Thanks,

Larry