[ALSA] unregister platform devices

Call platform_device_unregister() for all platform devices that we've
registered.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
diff --git a/sound/isa/gus/gusmax.c b/sound/isa/gus/gusmax.c
index d1b70ee..d4d2b2a 100644
--- a/sound/isa/gus/gusmax.c
+++ b/sound/isa/gus/gusmax.c
@@ -72,6 +72,8 @@
 module_param_array(pcm_channels, int, NULL, 0444);
 MODULE_PARM_DESC(pcm_channels, "Reserved PCM channels for GUS MAX driver.");
 
+static struct platform_device *devices[SNDRV_CARDS];
+
 struct snd_gusmax {
 	int irq;
 	struct snd_card *card;
@@ -364,6 +366,15 @@
 	},
 };
 
+static void __init_or_module snd_gusmax_unregister_all(void)
+{
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(devices); ++i)
+		platform_device_unregister(devices[i]);
+	platform_driver_unregister(&snd_gusmax_driver);
+}
+
 static int __init alsa_card_gusmax_init(void)
 {
 	int i, cards, err;
@@ -381,6 +392,7 @@
 			err = PTR_ERR(device);
 			goto errout;
 		}
+		devices[i] = device;
 		cards++;
 	}
 	if (!cards) {
@@ -393,13 +405,13 @@
 	return 0;
 
  errout:
-	platform_driver_unregister(&snd_gusmax_driver);
+	snd_gusmax_unregister_all();
 	return err;
 }
 
 static void __exit alsa_card_gusmax_exit(void)
 {
-	platform_driver_unregister(&snd_gusmax_driver);
+	snd_gusmax_unregister_all();
 }
 
 module_init(alsa_card_gusmax_init)