add small sleep before clearing usb halt condition

ChangeLog

@@ -6,6 +6,7 @@
 	- better handling of errors during calibration
 	- cleanup canceling debug messages
 	- remove old cancel() prototype
+	- small sleep before clearing usb halt condition
 
 2009-06-17  Stéphane Voltz <stef.dev at free.fr>
 	* backend/lexmark_low.c: cleanups, better logging in is_home_line()

backend/canon_dr.c

@@ -226,6 +226,7 @@
          - better handling of errors during calibration
          - cleanup canceling debug messages
          - remove old cancel() prototype
+         - small sleep before clearing usb halt condition
 
    SANE FLOW DIAGRAM
 
@@ -5999,6 +6000,8 @@ do_usb_clear(struct scanner *s, int clear, int runRS)
 
     DBG (10, "do_usb_clear: start\n");
 
+    usleep(100000);
+
     if(clear){
       DBG (15, "do_usb_clear: clear halt\n");
       ret = sanei_usb_clear_halt(s->fd);