ALSA: virmidi: Allocate resources with device-managed APIs

This patch converts the card object management with devres as a clean
up.  The remove callback gets reduced by that.

This should give no user-visible functional changes.

Link: https://lore.kernel.org/r/20210715075941.23332-74-tiwai@suse.deSigned-off-by: Takashi Iwai <tiwai@suse.de>

sound/drivers/virmidi.c

@@ -75,7 +75,7 @@ static int snd_virmidi_probe(struct platform_device *devptr)
 	int idx, err;
 	int dev = devptr->id;
 
-	err = snd_card_new(&devptr->dev, index[dev], id[dev], THIS_MODULE,
+	err = snd_devm_card_new(&devptr->dev, index[dev], id[dev], THIS_MODULE,
 				sizeof(struct snd_card_virmidi), &card);
 	if (err < 0)
 		return err;
@@ -94,7 +94,7 @@ static int snd_virmidi_probe(struct platform_device *devptr)
 
 		err = snd_virmidi_new(card, idx, &rmidi);
 		if (err < 0)
-			goto __nodev;
+			return err;
 		rdev = rmidi->private_data;
 		vmidi->midi[idx] = rmidi;
 		strcpy(rmidi->name, "Virtual Raw MIDI");
@@ -106,18 +106,10 @@ static int snd_virmidi_probe(struct platform_device *devptr)
 	sprintf(card->longname, "Virtual MIDI Card %i", dev + 1);
 
 	err = snd_card_register(card);
-	if (!err) {
-		platform_set_drvdata(devptr, card);
-		return 0;
-	}
-__nodev:
-	snd_card_free(card);
+	if (err)
 		return err;
-}
 
-static int snd_virmidi_remove(struct platform_device *devptr)
-{
-	snd_card_free(platform_get_drvdata(devptr));
+	platform_set_drvdata(devptr, card);
 	return 0;
 }
 
@@ -125,7 +117,6 @@ static int snd_virmidi_remove(struct platform_device *devptr)
 
 static struct platform_driver snd_virmidi_driver = {
 	.probe		= snd_virmidi_probe,
-	.remove		= snd_virmidi_remove,
 	.driver		= {
 		.name	= SND_VIRMIDI_DRIVER,
 	},