pps: timestamp is always passed to dcd_change()

Remove the code that gatheres timestamp in pps_tty_dcd_change() in case
passed ts parameter is NULL because it never happens in the current code.
Fix comments as well.

Signed-off-by: Alexander Gordeev <lasaine@lvk.cs.msu.su>
Acked-by: Rodolfo Giometti <giometti@linux.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Documentation/serial/tty.txt

@@ -107,7 +107,7 @@ write_wakeup()	-	May be called at any point between open and close.
 
 dcd_change()	-	Report to the tty line the current DCD pin status
 			changes and the relative timestamp. The timestamp
-			can be NULL.
+			cannot be NULL.
 
 
 Driver Access

drivers/pps/clients/pps-ldisc.c

@@ -32,14 +32,6 @@ static void pps_tty_dcd_change(struct tty_struct *tty, unsigned int status,
 				struct pps_event_time *ts)
 {
 	struct pps_device *pps = (struct pps_device *)tty->disc_data;
-	struct pps_event_time __ts;
-
-	/* First of all we get the time stamp... */
-	pps_get_ts(&__ts);
-
-	/* Does caller give us a timestamp? */
-	if (!ts)	/* No. Do it ourself! */
-		ts = &__ts;
 
 	BUG_ON(pps == NULL);
 

include/linux/tty_ldisc.h

@@ -104,7 +104,7 @@
  *			struct pps_event_time *ts)
  *
  *	Tells the discipline that the DCD pin has changed its status and
- *	the relative timestamp. Pointer ts can be NULL.
+ *	the relative timestamp. Pointer ts cannot be NULL.
  */
 
 #include <linux/fs.h>