Input: walkera0701 - fix crash on startup

The driver's timer must be set up before enabling IRQ handler, otherwise
bad things may happen.

Reported-and-tested-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Peter Popovec <popovec@fei.tuke.sk>
CC: stable@vger.kernel.org
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

1 files changed, 4 insertions, 3 deletions

diff --git a/drivers/input/joystick/walkera0701.c b/drivers/input/joystick/walkera0701.c
index 4dfa1eed4b7..f8f892b076e 100644
--- a/drivers/input/joystick/walkera0701.c
+++ b/drivers/input/joystick/walkera0701.c
@@ -196,6 +196,7 @@ static void walkera0701_close(struct input_dev *dev)
         struct walkera_dev *w = input_get_drvdata(dev);
 
         parport_disable_irq(w->parport);
+        hrtimer_cancel(&w->timer);
 }
 
 static int walkera0701_connect(struct walkera_dev *w, int parport)
@@ -224,6 +225,9 @@ static int walkera0701_connect(struct walkera_dev *w, int parport)
         if (parport_claim(w->pardevice))
                 goto init_err1;
 
+        hrtimer_init(&w->timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
+        w->timer.function = timer_handler;
+
         w->input_dev = input_allocate_device();
         if (!w->input_dev)
                 goto init_err2;
@@ -254,8 +258,6 @@ static int walkera0701_connect(struct walkera_dev *w, int parport)
         if (err)
                 goto init_err3;
 
-        hrtimer_init(&w->timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
-        w->timer.function = timer_handler;
         return 0;
 
  init_err3:
@@ -271,7 +273,6 @@ static int walkera0701_connect(struct walkera_dev *w, int parport)
 
 static void walkera0701_disconnect(struct walkera_dev *w)
 {
-        hrtimer_cancel(&w->timer);
         input_unregister_device(w->input_dev);
         parport_release(w->pardevice);
         parport_unregister_device(w->pardevice);