ALSA: bcd2000: 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 <tiwai@suse.de>
Link: https://patch.msgid.link/20250829150724.6886-9-tiwai@suse.de

diff --git a/sound/usb/bcd2000/bcd2000.c b/sound/usb/bcd2000/bcd2000.c
index 392b4d8e9e7696443c5181ba6098a3da4ab7e456..bebb48cb9abc8c1f0cd254d0ad92a6fc868c37ca 100644 (file)
--- a/sound/usb/bcd2000/bcd2000.c
+++ b/sound/usb/bcd2000/bcd2000.c
@@ -369,23 +369,19 @@ static int bcd2000_probe(struct usb_interface *interface,
        char usb_path[32];
        int err;
 
-       mutex_lock(&devices_mutex);
+       guard(mutex)(&devices_mutex);
 
        for (card_index = 0; card_index < SNDRV_CARDS; ++card_index)
                if (!test_bit(card_index, devices_used))
                        break;
 
-       if (card_index >= SNDRV_CARDS) {
-               mutex_unlock(&devices_mutex);
+       if (card_index >= SNDRV_CARDS)
                return -ENOENT;
-       }
 
        err = snd_card_new(&interface->dev, index[card_index], id[card_index],
                        THIS_MODULE, sizeof(*bcd2k), &card);
-       if (err < 0) {
-               mutex_unlock(&devices_mutex);
+       if (err < 0)
                return err;
-       }
 
        bcd2k = card->private_data;
        bcd2k->dev = interface_to_usbdev(interface);
@@ -413,14 +409,12 @@ static int bcd2000_probe(struct usb_interface *interface,
        usb_set_intfdata(interface, bcd2k);
        set_bit(card_index, devices_used);
 
-       mutex_unlock(&devices_mutex);
        return 0;
 
 probe_error:
        dev_info(&bcd2k->dev->dev, PREFIX "error during probing");
        bcd2000_free_usb_related_resources(bcd2k, interface);
        snd_card_free(card);
-       mutex_unlock(&devices_mutex);
        return err;
 }
 
@@ -431,7 +425,7 @@ static void bcd2000_disconnect(struct usb_interface *interface)
        if (!bcd2k)
                return;
 
-       mutex_lock(&devices_mutex);
+       guard(mutex)(&devices_mutex);
 
        /* make sure that userspace cannot create new requests */
        snd_card_disconnect(bcd2k->card);
@@ -441,8 +435,6 @@ static void bcd2000_disconnect(struct usb_interface *interface)
        clear_bit(bcd2k->card_index, devices_used);
 
        snd_card_free_when_closed(bcd2k->card);
-
-       mutex_unlock(&devices_mutex);
 }
 
 static struct usb_driver bcd2000_driver = {