pda_power: implement polling

Signed-off-by: Anton Vorontsov <cbou@mail.ru>
diff --git a/include/linux/pda_power.h b/include/linux/pda_power.h
index 1375f15..225beb1 100644
--- a/include/linux/pda_power.h
+++ b/include/linux/pda_power.h
@@ -26,6 +26,7 @@
 
 	unsigned int wait_for_status; /* msecs, default is 500 */
 	unsigned int wait_for_charger; /* msecs, default is 500 */
+	unsigned int polling_interval; /* msecs, default is 2000 */
 };
 
 #endif /* __PDA_POWER_H__ */