[ALSA] pcxhr - Fix the sample rate changes

Modules: Digigram PCXHR driver

Fix the hardware set up when the sample rate is changed multiple times.
Signed-off-by: Takashi Iwai <tiwai@suse.de>

sound/pci/pcxhr/pcxhr.c

@@ -744,13 +744,14 @@ static int pcxhr_prepare(struct snd_pcm_substream *subs)
 		/* only the first stream can choose the sample rate */
 		/* the further opened streams will be limited to its frequency (see open) */
 		/* set the clock only once (first stream) */
-		if (mgr->sample_rate == 0) {
+		if (mgr->sample_rate != subs->runtime->rate) {
 			err = pcxhr_set_clock(mgr, subs->runtime->rate);
 			if (err)
 				break;
+			if (mgr->sample_rate == 0)
+				/* start the DSP-timer */
+				err = pcxhr_hardware_timer(mgr, 1);
 			mgr->sample_rate = subs->runtime->rate;
-
-			err = pcxhr_hardware_timer(mgr, 1);	/* start the DSP-timer */
 		}
 	} while(0);	/* do only once (so we can use break instead of goto) */