HID: sony: Fix work queue issues.

Don't initialize force-feedback for devices that don't support it to avoid calls
to schedule_work() with an uninitialized work_struct.

Move the cancel_work_sync() call out of sony_destroy_ff() since the state worker
is used for the LEDs even when force-feedback is disabled.

Remove sony_destroy_ff() to avoid a compiler warning since it is no longer used.

Signed-off-by: Frank Praznik <frank.praznik@oh.rr.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

drivers/hid/hid-sony.c

@@ -42,6 +42,7 @@
 #define DUALSHOCK4_CONTROLLER_BT BIT(6)
 
 #define SONY_LED_SUPPORT (SIXAXIS_CONTROLLER_USB | BUZZ_CONTROLLER | DUALSHOCK4_CONTROLLER_USB)
+#define SONY_FF_SUPPORT (SIXAXIS_CONTROLLER_USB | DUALSHOCK4_CONTROLLER_USB)
 
 #define MAX_LEDS 4
 
@@ -499,6 +500,7 @@ struct sony_sc {
  __u8 right;
 #endif
 
+ __u8 worker_initialized;
  __u8 led_state[MAX_LEDS];
  __u8 led_count;
 };
@@ -993,22 +995,11 @@ static int sony_init_ff(struct hid_device *hdev)
  return input_ff_create_memless(input_dev, NULL, sony_play_effect);
 }
 
-static void sony_destroy_ff(struct hid_device *hdev)
-{
- struct sony_sc *sc = hid_get_drvdata(hdev);
-
- cancel_work_sync(&sc->state_worker);
-}
-
 #else
 static int sony_init_ff(struct hid_device *hdev)
 {
  return 0;
 }
-
-static void sony_destroy_ff(struct hid_device *hdev)
-{
-}
 #endif
 
 static int sony_set_output_report(struct sony_sc *sc, int req_id, int req_size)
@@ -1077,6 +1068,8 @@ static int sony_probe(struct hid_device *hdev, const struct hid_device_id *id)
  if (sc->quirks & SIXAXIS_CONTROLLER_USB) {
  hdev->hid_output_raw_report = sixaxis_usb_output_raw_report;
  ret = sixaxis_set_operational_usb(hdev);
+
+ sc->worker_initialized = 1;
  INIT_WORK(&sc->state_worker, sixaxis_state_worker);
  }
  else if (sc->quirks & SIXAXIS_CONTROLLER_BT)
@@ -1087,6 +1080,7 @@ static int sony_probe(struct hid_device *hdev, const struct hid_device_id *id)
  if (ret < 0)
  goto err_stop;
 
+ sc->worker_initialized = 1;
  INIT_WORK(&sc->state_worker, dualshock4_state_worker);
  } else {
  ret = 0;
@@ -1101,9 +1095,11 @@ static int sony_probe(struct hid_device *hdev, const struct hid_device_id *id)
  goto err_stop;
  }
 
- ret = sony_init_ff(hdev);
- if (ret < 0)
- goto err_stop;
+ if (sc->quirks & SONY_FF_SUPPORT) {
+ ret = sony_init_ff(hdev);
+ if (ret < 0)
+ goto err_stop;
+ }
 
  return 0;
 err_stop:
@@ -1120,7 +1116,8 @@ static void sony_remove(struct hid_device *hdev)
  if (sc->quirks & SONY_LED_SUPPORT)
  sony_leds_remove(hdev);
 
- sony_destroy_ff(hdev);
+ if (sc->worker_initialized)
+ cancel_work_sync(&sc->state_worker);
 
  hid_hw_stop(hdev);
 }