s390/sclp: Use monotonic clock in sclp_sync_wait()

sclp_sync_wait() should use the monotonic clock for the delay loop.
Otherwise the code won't work correctly when the clock is changed.

Signed-off-by: Sven Schnelle <svens@linux.ibm.com>
Reviewed-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>

Author: svens-s390

drivers/s390/char/sclp.c

@@ -720,7 +720,7 @@ sclp_sync_wait(void)
 	timeout = 0;
 	if (timer_pending(&sclp_request_timer)) {
 		/* Get timeout TOD value */
-		timeout = get_tod_clock_fast() +
+		timeout = get_tod_clock_monotonic() +
 			  sclp_tod_from_jiffies(sclp_request_timer.expires -
 						jiffies);
 	}
@@ -740,7 +740,7 @@ sclp_sync_wait(void)
 	/* Loop until driver state indicates finished request */
 	while (sclp_running_state != sclp_running_state_idle) {
 		/* Check for expired request timer */
-		if (get_tod_clock_fast() > timeout && timer_delete(&sclp_request_timer))
+		if (get_tod_clock_monotonic() > timeout && timer_delete(&sclp_request_timer))
 			sclp_request_timer.function(&sclp_request_timer);
 		cpu_relax();
 	}