ALSA: aloop: Fix random zeros in capture data when using jiffies timer

commit 3e48940 upstream.

In loopback_jiffies_timer_pos_update(), we are getting jiffies twice.
First time for playback, second time for capture. Jiffies can be updated
between these two calls and if the capture jiffies is larger, extra zeros
will be filled in the capture buffer.

Change to get jiffies once and use it for both playback and capture.

Signed-off-by: Pattara Teerapong <pteerapong@chromium.org>
Cc: <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20220901144036.4049060-1-pteerapong@chromium.org
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

sound/drivers/aloop.c

@@ -605,17 +605,18 @@ static unsigned int loopback_jiffies_timer_pos_update
 			cable->streams[SNDRV_PCM_STREAM_PLAYBACK];
 	struct loopback_pcm *dpcm_capt =
 			cable->streams[SNDRV_PCM_STREAM_CAPTURE];
-	unsigned long delta_play = 0, delta_capt = 0;
+	unsigned long delta_play = 0, delta_capt = 0, cur_jiffies;
 	unsigned int running, count1, count2;
 
+	cur_jiffies = jiffies;
 	running = cable->running ^ cable->pause;
 	if (running & (1 << SNDRV_PCM_STREAM_PLAYBACK)) {
-		delta_play = jiffies - dpcm_play->last_jiffies;
+		delta_play = cur_jiffies - dpcm_play->last_jiffies;
 		dpcm_play->last_jiffies += delta_play;
 	}
 
 	if (running & (1 << SNDRV_PCM_STREAM_CAPTURE)) {
-		delta_capt = jiffies - dpcm_capt->last_jiffies;
+		delta_capt = cur_jiffies - dpcm_capt->last_jiffies;
 		dpcm_capt->last_jiffies += delta_capt;
 	}