add poll_event*()

@@ -47,4 +47,43 @@ static inline void ssleep(unsigned int s
 	msleep(seconds * 1000);
 }
 
+/*
+ * poll_event* check if an @cond is true every interval milliseconds, up
+ * to a @timeout maximum, if specified.
+ * The *_interruptible versions will sleep in TASK_INTERRUPTIBLE
+ * (instead of TASK_UNINTERRUPTIBLE) and will return early on signals
+ */
+
+#define poll_event(cond, interval)				\
+do {								\
+	while (cond)						\
+		msleep(interval);				\
+} while(0)
+
+#define poll_event_timeout(cond, interval, timeout)			\
+do {									\
+	unsigned long stop = jiffies + msecs_to_jiffies(timeout);	\
+	while (cond && time_before(jiffies, stop))			\
+		msleep(interval);					\
+} while(0)
+
+#define poll_event_interruptible(cond, interval)		\
+do {								\
+	while (cond) {						\
+		msleep_interruptible(interval);			\
+		if (signal_pending(current))			\
+			break;					\
+	}							\
+} while(0);
+
+#define poll_event_interruptible_timeout(cond, interval, timeout)	\
+do {									\
+	unsigned long stop = jiffies + msecs_to_jiffies(timeout);	\
+	while (cond && time_before(jiffies, stop)) {			\
+		msleep_interruptible(interval);				\
+		if (signal_pending(current))				\
+			break;						\
+	}								\
+} while(0);
+
 #endif /* defined(_LINUX_DELAY_H) */