[RFKILL]: Add support for hardware-only rfkill buttons

Buttons that work directly on hardware cannot support
the "user_claim" functionality. Add a flag to signal
this and return -EOPNOTSUPP in this case.
b43 is such a device.

Signed-off-by: Michael Buesch <mb@bu3sch.de>
Acked-by: Ivo van Doorn <IvDoorn@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 3 insertions, 0 deletions

diff --git a/include/linux/rfkill.h b/include/linux/rfkill.h
index 26fddea12c25..0ce5e0b52dbd 100644
--- a/include/linux/rfkill.h
+++ b/include/linux/rfkill.h
@@ -52,6 +52,8 @@ enum rfkill_state {
  * @type: Radio type which the button controls, the value stored
  *      here should be a value from enum rfkill_type.
  * @state: State of the switch (on/off).
+ * @user_claim_unsupported: Whether the hardware supports exclusive
+ *      RF-kill control by userspace. Set this before registering.
  * @user_claim: Set when the switch is controlled exlusively by userspace.
  * @mutex: Guards switch state transitions
  * @data: Pointer to the RF button drivers private data which will be
@@ -69,6 +71,7 @@ struct rfkill {
         enum rfkill_type type;
 
         enum rfkill_state state;
+        bool user_claim_unsupported;
         bool user_claim;
 
         struct mutex mutex;