rfkill: preserve state across suspend

The rfkill class API requires that the driver connected to a class
call rfkill_force_state() on resume to update the real state of the
rfkill controller, OR that it provides a get_state() hook.

This means there is potentially a hidden call in the resume code flow
that changes rfkill->state (i.e. rfkill_force_state()), so the
previous state of the transmitter was being lost.

The simplest and most future-proof way to fix this is to explicitly
store the pre-sleep state on the rfkill structure, and restore from
that on resume.

Signed-off-by: Henrique de Moraes Holschuh <hmh@hmh.eng.br>
Acked-by: Ivo van Doorn <IvDoorn@gmail.com>
Cc: Matthew Garrett <mjg59@srcf.ucam.org>
Cc: Alan Jenkins <alan-jenkins@tuffmail.co.uk>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 1 insertions, 0 deletions

diff --git a/include/linux/rfkill.h b/include/linux/rfkill.h
index 4cd64b0d9825..f376a93927f7 100644
--- a/include/linux/rfkill.h
+++ b/include/linux/rfkill.h
@@ -108,6 +108,7 @@ struct rfkill {
 
         struct device dev;
         struct list_head node;
+        enum rfkill_state state_for_resume;
 };
 #define to_rfkill(d)    container_of(d, struct rfkill, dev)