ALSA: synth: Use guard() for mutex locks

Replace the manual mutex lock/unlock pairs with guard() for code
simplification.

Only code refactoring, and no behavior change.

Signed-off-by: Takashi Iwai <[e-mail]>
Link: https://patch.msgid.link/[e-mail]

sound/synth/emux/emux_proc.c

···
 	int i;
 
 	emu = entry->private_data;
-	mutex_lock(&emu->register_mutex);
+	guard(mutex)(&emu->register_mutex);
 	if (emu->name)
 		snd_iprintf(buf, "Device: %s\n", emu->name);
 	snd_iprintf(buf, "Ports: %d\n", emu->num_ports);
···
 		snd_iprintf(buf, "Memory Size: 0\n");
 	}
 	if (emu->sflist) {
-		mutex_lock(&emu->sflist->presets_mutex);
+		guard(mutex)(&emu->sflist->presets_mutex);
 		snd_iprintf(buf, "SoundFonts: %d\n", emu->sflist->fonts_size);
 		snd_iprintf(buf, "Instruments: %d\n", emu->sflist->zone_counter);
 		snd_iprintf(buf, "Samples: %d\n", emu->sflist->sample_counter);
 		snd_iprintf(buf, "Locked Instruments: %d\n", emu->sflist->zone_locked);
 		snd_iprintf(buf, "Locked Samples: %d\n", emu->sflist->sample_locked);
-		mutex_unlock(&emu->sflist->presets_mutex);
 	}
 #if 0  /* debug */
 	if (emu->voices[0].state != SNDRV_EMUX_ST_OFF && emu->voices[0].ch >= 0) {
···
 		snd_iprintf(buf, "sample_mode=%x, rate=%x\n", vp->reg.sample_mode, vp->reg.rate_offset);
 	}
 #endif
-	mutex_unlock(&emu->register_mutex);
 }
 
 

sound/synth/emux/emux_seq.c

···
 
 int snd_emux_inc_count(struct snd_emux *emu)
 {
-	int ret;
-
-	mutex_lock(&emu->register_mutex);
-	ret = __snd_emux_inc_count(emu);
-	mutex_unlock(&emu->register_mutex);
-	return ret;
+	guard(mutex)(&emu->register_mutex);
+	return __snd_emux_inc_count(emu);
 }
 
 /*
···
 
 void snd_emux_dec_count(struct snd_emux *emu)
 {
-	mutex_lock(&emu->register_mutex);
+	guard(mutex)(&emu->register_mutex);
 	__snd_emux_dec_count(emu);
-	mutex_unlock(&emu->register_mutex);
 }
 
 /*
···
 	if (snd_BUG_ON(!emu))
 		return -EINVAL;
 
-	mutex_lock(&emu->register_mutex);
+	guard(mutex)(&emu->register_mutex);
 	snd_emux_init_port(p);
 	__snd_emux_inc_count(emu);
-	mutex_unlock(&emu->register_mutex);
 	return 0;
 }
 
···
 	if (snd_BUG_ON(!emu))
 		return -EINVAL;
 
-	mutex_lock(&emu->register_mutex);
+	guard(mutex)(&emu->register_mutex);
 	snd_emux_sounds_off_all(p);
 	__snd_emux_dec_count(emu);
-	mutex_unlock(&emu->register_mutex);
 	return 0;
 }
 

sound/synth/util_mem.c

···
 struct snd_util_memblk *
 snd_util_mem_alloc(struct snd_util_memhdr *hdr, int size)
 {
-	struct snd_util_memblk *blk;
-	mutex_lock(&hdr->block_mutex);
-	blk = __snd_util_mem_alloc(hdr, size);
-	mutex_unlock(&hdr->block_mutex);
-	return blk;
+	guard(mutex)(&hdr->block_mutex);
+	return __snd_util_mem_alloc(hdr, size);
 }
 
 
···
 	if (snd_BUG_ON(!hdr || !blk))
 		return -EINVAL;
 
-	mutex_lock(&hdr->block_mutex);
+	guard(mutex)(&hdr->block_mutex);
 	__snd_util_mem_free(hdr, blk);
-	mutex_unlock(&hdr->block_mutex);
 	return 0;
 }
 
···
  */
 int snd_util_mem_avail(struct snd_util_memhdr *hdr)
 {
-	unsigned int size;
-	mutex_lock(&hdr->block_mutex);
-	size = hdr->size - hdr->used;
-	mutex_unlock(&hdr->block_mutex);
-	return size;
+	guard(mutex)(&hdr->block_mutex);
+	return hdr->size - hdr->used;
 }