rfkill: protect suspended rfkill controllers

Guard rfkill controllers attached to a rfkill class against state changes
after class suspend has been issued.

Signed-off-by: Henrique de Moraes Holschuh <hmh@hmh.eng.br>
Acked-by: Ivo van Doorn <IvDoorn@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/Documentation/rfkill.txt b/Documentation/rfkill.txt
index 28b6ec8..6fcb306 100644
--- a/Documentation/rfkill.txt
+++ b/Documentation/rfkill.txt
@@ -363,6 +363,11 @@
 when possible) the overall transmitter rfkill state, not of a particular rfkill
 line.
 
+5. During suspend, the rfkill class will attempt to soft-block the radio
+through a call to rfkill->toggle_radio, and will try to restore its previous
+state during resume.  After a rfkill class is suspended, it will *not* call
+rfkill->toggle_radio until it is resumed.
+
 Example of a WLAN wireless driver connected to the rfkill subsystem:
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