[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/gusextreme.c b/sound/isa/gus/gusextreme.c
index 6fad973..239f16e 100644
--- a/sound/isa/gus/gusextreme.c
+++ b/sound/isa/gus/gusextreme.c
@@ -87,6 +87,8 @@
 module_param_array(pcm_channels, int, NULL, 0444);
 MODULE_PARM_DESC(pcm_channels, "Reserved PCM channels for GUS Extreme driver.");
 
+struct platform_device *devices[SNDRV_CARDS];
+
 
 #define PFX	"gusextreme: "
 
@@ -337,6 +339,15 @@
 	},
 };
 
+static void __init_or_module snd_gusextreme_unregister_all(void)
+{
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(devices); ++i)
+		platform_device_unregister(devices[i]);
+	platform_driver_unregister(&snd_gusextreme_driver);
+}
+
 static int __init alsa_card_gusextreme_init(void)
 {
 	int i, cards, err;
@@ -354,6 +365,7 @@
 			err = PTR_ERR(device);
 			goto errout;
 		}
+		devices[i] = device;
 		cards++;
 	}
 	if (!cards) {
@@ -366,13 +378,13 @@
 	return 0;
 
  errout:
-	platform_driver_unregister(&snd_gusextreme_driver);
+	snd_gusextreme_unregister_all();
 	return err;
 }
 
 static void __exit alsa_card_gusextreme_exit(void)
 {
-	platform_driver_unregister(&snd_gusextreme_driver);
+	snd_gusextreme_unregister_all();
 }
 
 module_init(alsa_card_gusextreme_init)