Vibrator: clarify the API
Put stronger requirements on the vibrator API:
- vibratorOn must not be called if the vibrator is already called (requirement
on the caller);
- vibratorOff must cancel any ongoing vibration (requirement on the callee).
Change-Id: Ic2fcd29903bf5a11a19c731de355d19c06c4e0e2
Signed-off-by: David Wagner <david.wagner@intel.com>
diff --git a/include/hardware/vibrator.h b/include/hardware/vibrator.h
index 795d23e..d1a300a 100644
--- a/include/hardware/vibrator.h
+++ b/include/hardware/vibrator.h
@@ -39,8 +39,8 @@
/** Turn on vibrator
*
- * What happens when this function is called while the the timeout of a
- * previous call has not expired is implementation dependent.
+ * This function must only be called after the previous timeout has expired or
+ * was canceled (through vibrator_off()).
*
* @param timeout_ms number of milliseconds to vibrate
*
@@ -50,8 +50,7 @@
/** Turn off vibrator
*
- * It is not guaranteed that the vibrator will be immediately stopped: the
- * behaviour is implementation dependent.
+ * Cancel a previously-started vibration, if any.
*
* @return 0 in case of success, negative errno code else
*/