ASoC: Add more natural support for no-DMA DAIs

Since we can now support multiple platforms allow machines to not specify
a platform in a DAI link. Since the rest of the code requires that we have
a struct device for all objects we do this by substituting in a dummy
device that we register automatically.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: Jassi Brar <jassisinghbrar@gmail.com>
Acked-by: Liam Girdwood <lrg@ti.com>

1 files changed, 55 insertions, 0 deletions

diff --git a/sound/soc/soc-utils.c b/sound/soc/soc-utils.c
index 3f45e6a439bf..286579140882 100644
--- a/sound/soc/soc-utils.c
+++ b/sound/soc/soc-utils.c
@@ -13,6 +13,7 @@
  *  option) any later version.
  */
 
+#include <linux/platform_device.h>
 #include <sound/core.h>
 #include <sound/pcm.h>
 #include <sound/pcm_params.h>
@@ -55,3 +56,57 @@ int snd_soc_params_to_bclk(struct snd_pcm_hw_params *params)
 		return ret;
 }
 EXPORT_SYMBOL_GPL(snd_soc_params_to_bclk);
+
+static struct snd_soc_platform_driver dummy_platform;
+
+static __devinit int snd_soc_dummy_probe(struct platform_device *pdev)
+{
+	return snd_soc_register_platform(&pdev->dev, &dummy_platform);
+}
+
+static __devexit int snd_soc_dummy_remove(struct platform_device *pdev)
+{
+	snd_soc_unregister_platform(&pdev->dev);
+
+	return 0;
+}
+
+static struct platform_driver soc_dummy_driver = {
+	.driver = {
+		.name = "snd-soc-dummy",
+		.owner = THIS_MODULE,
+	},
+	.probe = snd_soc_dummy_probe,
+	.remove = __devexit_p(snd_soc_dummy_remove),
+};
+
+static struct platform_device *soc_dummy_dev;
+
+static int __init snd_soc_util_init(void)
+{
+	int ret;
+
+	soc_dummy_dev = platform_device_alloc("snd-soc-dummy", -1);
+	if (!soc_dummy_dev)
+		return -ENOMEM;
+
+	ret = platform_device_add(soc_dummy_dev);
+	if (ret != 0) {
+		platform_device_put(soc_dummy_dev);
+		return ret;
+	}
+
+	ret = platform_driver_register(&soc_dummy_driver);
+	if (ret != 0)
+		platform_device_unregister(soc_dummy_dev);
+
+	return ret;
+}
+module_init(snd_soc_util_init);
+
+static void __exit snd_soc_util_exit(void)
+{
+	platform_device_unregister(soc_dummy_dev);
+	platform_driver_unregister(&soc_dummy_driver);
+}
+module_exit(snd_soc_util_exit);