ALSA: rawmidi: Simplify error paths

Apply the standard idiom: rewrite the multiple unlocks in error paths
in the goto-error-and-single-unlock way.

Just a code refactoring, and no functional changes.

Signed-off-by: Takashi Iwai <tiwai@suse.de>

diff --git a/sound/core/rawmidi.c b/sound/core/rawmidi.c
index 14dec13..6b24c2d 100644 (file)
--- a/sound/core/rawmidi.c
+++ b/sound/core/rawmidi.c
@@ -338,22 +338,20 @@ int snd_rawmidi_kernel_open(struct snd_card *card, int device, int subdevice,
                            int mode, struct snd_rawmidi_file *rfile)
 {
        struct snd_rawmidi *rmidi;
-       int err;
+       int err = 0;
 
        if (snd_BUG_ON(!rfile))
                return -EINVAL;
 
        mutex_lock(&register_mutex);
        rmidi = snd_rawmidi_search(card, device);
-       if (rmidi == NULL) {
-               mutex_unlock(&register_mutex);
-               return -ENODEV;
-       }
-       if (!try_module_get(rmidi->card->module)) {
-               mutex_unlock(&register_mutex);
-               return -ENXIO;
-       }
+       if (!rmidi)
+               err = -ENODEV;
+       else if (!try_module_get(rmidi->card->module))
+               err = -ENXIO;
        mutex_unlock(&register_mutex);
+       if (err < 0)
+               return err;
 
        mutex_lock(&rmidi->open_mutex);
        err = rawmidi_open_priv(rmidi, subdevice, mode, rfile);
@@ -1581,26 +1579,25 @@ int snd_rawmidi_new(struct snd_card *card, char *id, int device,
                                           &rmidi->streams[SNDRV_RAWMIDI_STREAM_INPUT],
                                           SNDRV_RAWMIDI_STREAM_INPUT,
                                           input_count);
-       if (err < 0) {
-               snd_rawmidi_free(rmidi);
-               return err;
-       }
+       if (err < 0)
+               goto error;
        err = snd_rawmidi_alloc_substreams(rmidi,
                                           &rmidi->streams[SNDRV_RAWMIDI_STREAM_OUTPUT],
                                           SNDRV_RAWMIDI_STREAM_OUTPUT,
                                           output_count);
-       if (err < 0) {
-               snd_rawmidi_free(rmidi);
-               return err;
-       }
+       if (err < 0)
+               goto error;
        err = snd_device_new(card, SNDRV_DEV_RAWMIDI, rmidi, &ops);
-       if (err < 0) {
-               snd_rawmidi_free(rmidi);
-               return err;
-       }
+       if (err < 0)
+               goto error;
+
        if (rrawmidi)
                *rrawmidi = rmidi;
        return 0;
+
+ error:
+       snd_rawmidi_free(rmidi);
+       return err;
 }
 EXPORT_SYMBOL(snd_rawmidi_new);
 
@@ -1660,30 +1657,27 @@ static int snd_rawmidi_dev_register(struct snd_device *device)
 
        if (rmidi->device >= SNDRV_RAWMIDI_DEVICES)
                return -ENOMEM;
+       err = 0;
        mutex_lock(&register_mutex);
-       if (snd_rawmidi_search(rmidi->card, rmidi->device)) {
-               mutex_unlock(&register_mutex);
-               return -EBUSY;
-       }
-       list_add_tail(&rmidi->list, &snd_rawmidi_devices);
+       if (snd_rawmidi_search(rmidi->card, rmidi->device))
+               err = -EBUSY;
+       else
+               list_add_tail(&rmidi->list, &snd_rawmidi_devices);
        mutex_unlock(&register_mutex);
+       if (err < 0)
+               return err;
+
        err = snd_register_device(SNDRV_DEVICE_TYPE_RAWMIDI,
                                  rmidi->card, rmidi->device,
                                  &snd_rawmidi_f_ops, rmidi, &rmidi->dev);
        if (err < 0) {
                rmidi_err(rmidi, "unable to register\n");
-               mutex_lock(&register_mutex);
-               list_del(&rmidi->list);
-               mutex_unlock(&register_mutex);
-               return err;
+               goto error;
        }
-       if (rmidi->ops && rmidi->ops->dev_register &&
-           (err = rmidi->ops->dev_register(rmidi)) < 0) {
-               snd_unregister_device(&rmidi->dev);
-               mutex_lock(&register_mutex);
-               list_del(&rmidi->list);
-               mutex_unlock(&register_mutex);
-               return err;
+       if (rmidi->ops && rmidi->ops->dev_register) {
+               err = rmidi->ops->dev_register(rmidi);
+               if (err < 0)
+                       goto error_unregister;
        }
 #ifdef CONFIG_SND_OSSEMUL
        rmidi->ossreg = 0;
@@ -1735,6 +1729,14 @@ static int snd_rawmidi_dev_register(struct snd_device *device)
        }
 #endif
        return 0;
+
+ error_unregister:
+       snd_unregister_device(&rmidi->dev);
+ error:
+       mutex_lock(&register_mutex);
+       list_del(&rmidi->list);
+       mutex_unlock(&register_mutex);
+       return err;
 }
 
 static int snd_rawmidi_dev_disconnect(struct snd_device *device)