ASoC: Add ADAU1977 CODEC driver

This patch adds support for the ADAU1977, ADAU1978 and ADAU1979 audio CODEC
devices. They are a family of 4-channel differential input audio ADC devices.
They can be connected to either a SPI or I2C bus. The driver is implemented in
three modules, one main module (adau1977.ko) which implements the device logic
and one module each for SPI (adau1977-spi.ko) and I2C (adau1977-i2c.ko) bus
access.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Mark Brown <broonie@linaro.org>

sound/soc/codecs/adau1977-i2c.c

@@ -0,0 +1,59 @@
+/*
+ * ADAU1977/ADAU1978/ADAU1979 driver
+ *
+ * Copyright 2014 Analog Devices Inc.
+ *  Author: Lars-Peter Clausen <lars@metafoo.de>
+ *
+ * Licensed under the GPL-2.
+ */
+
+#include <linux/i2c.h>
+#include <linux/mod_devicetable.h>
+#include <linux/module.h>
+#include <linux/regmap.h>
+#include <sound/soc.h>
+
+#include "adau1977.h"
+
+static int adau1977_i2c_probe(struct i2c_client *client,
+	const struct i2c_device_id *id)
+{
+	struct regmap_config config;
+
+	config = adau1977_regmap_config;
+	config.val_bits = 8;
+	config.reg_bits = 8;
+
+	return adau1977_probe(&client->dev,
+		devm_regmap_init_i2c(client, &config),
+		id->driver_data, NULL);
+}
+
+static int adau1977_i2c_remove(struct i2c_client *client)
+{
+	snd_soc_unregister_codec(&client->dev);
+	return 0;
+}
+
+static const struct i2c_device_id adau1977_i2c_ids[] = {
+	{ "adau1977", ADAU1977 },
+	{ "adau1978", ADAU1978 },
+	{ "adau1979", ADAU1978 },
+	{ }
+};
+MODULE_DEVICE_TABLE(i2c, adau1977_i2c_ids);
+
+static struct i2c_driver adau1977_i2c_driver = {
+	.driver = {
+		.name = "adau1977",
+		.owner = THIS_MODULE,
+	},
+	.probe = adau1977_i2c_probe,
+	.remove = adau1977_i2c_remove,
+	.id_table = adau1977_i2c_ids,
+};
+module_i2c_driver(adau1977_i2c_driver);
+
+MODULE_DESCRIPTION("ASoC ADAU1977/ADAU1978/ADAU1979 driver");
+MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>");
+MODULE_LICENSE("GPL");