ALSA: hrtimer: Use guard() for locking

We can simplify the code gracefully with new guard() macro and co for
automatic cleanup of locks.

Only the code refactoring, and no functional changes.
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Link: https://lore.kernel.org/r/20240227085306.9764-5-tiwai@suse.de

sound/core/hrtimer.c

@@ -35,12 +35,12 @@ static enum hrtimer_restart snd_hrtimer_callback(struct hrtimer *hrt)
 	unsigned long ticks;
 	enum hrtimer_restart ret = HRTIMER_NORESTART;
 
-	spin_lock(&t->lock);
-	if (!t->running)
-		goto out; /* fast path */
-	stime->in_callback = true;
-	ticks = t->sticks;
-	spin_unlock(&t->lock);
+	scoped_guard(spinlock, &t->lock) {
+		if (!t->running)
+			return HRTIMER_NORESTART; /* fast path */
+		stime->in_callback = true;
+		ticks = t->sticks;
+	}
 
 	/* calculate the drift */
 	delta = ktime_sub(hrt->base->get_time(), hrtimer_get_expires(hrt));
@@ -49,15 +49,13 @@ static enum hrtimer_restart snd_hrtimer_callback(struct hrtimer *hrt)
 
 	snd_timer_interrupt(stime->timer, ticks);
 
-	spin_lock(&t->lock);
+	guard(spinlock)(&t->lock);
 	if (t->running) {
 		hrtimer_add_expires_ns(hrt, t->sticks * resolution);
 		ret = HRTIMER_RESTART;
 	}
 
 	stime->in_callback = false;
- out:
-	spin_unlock(&t->lock);
 	return ret;
 }
 
@@ -80,10 +78,10 @@ static int snd_hrtimer_close(struct snd_timer *t)
 	struct snd_hrtimer *stime = t->private_data;
 
 	if (stime) {
-		spin_lock_irq(&t->lock);
-		t->running = 0; /* just to be sure */
-		stime->in_callback = 1; /* skip start/stop */
-		spin_unlock_irq(&t->lock);
+		scoped_guard(spinlock_irq, &t->lock) {
+			t->running = 0; /* just to be sure */
+			stime->in_callback = 1; /* skip start/stop */
+		}
 
 		hrtimer_cancel(&stime->hrt);
 		kfree(stime);