ASoC: Add suspend and resume callbacks to Wolfson CODEC drivers

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
diff --git a/sound/soc/codecs/wm8940.c b/sound/soc/codecs/wm8940.c
index b8e17d6..b69210a 100644
--- a/sound/soc/codecs/wm8940.c
+++ b/sound/soc/codecs/wm8940.c
@@ -916,6 +916,21 @@
 	return 0;
 }
 
+#ifdef CONFIG_PM
+static int wm8940_i2c_suspend(struct i2c_client *client, pm_message_t msg)
+{
+	return snd_soc_suspend_device(&client->dev);
+}
+
+static int wm8940_i2c_resume(struct i2c_client *client)
+{
+	return snd_soc_resume_device(&client->dev);
+}
+#else
+#define wm8940_i2c_suspend NULL
+#define wm8940_i2c_resume NULL
+#endif
+
 static const struct i2c_device_id wm8940_i2c_id[] = {
 	{ "wm8940", 0 },
 	{ }
@@ -929,6 +944,8 @@
 	},
 	.probe = wm8940_i2c_probe,
 	.remove = __devexit_p(wm8940_i2c_remove),
+	.suspend = wm8940_i2c_suspend,
+	.resume = wm8940_i2c_resume,
 	.id_table = wm8940_i2c_id,
 };