usb: gadget: Add Audio Class 2.0 Driver

This is a flexible USB Audio Class 2.0 compliant gadget driver that
implements a simple topology with a virtual sound card exposed at
the function side.

The driver doesn't expect any real audio codec to be present on the
function - the audio streams are simply sinked to and sourced from a
virtual ALSA sound card created. The user-space application may choose
to do whatever it wants with the data received from the USB Host and
choose to provide whatever it wants as audio data to the USB Host.

Capture(USB-Out) and Playback(USB-In) can be run at independent
configurations specified via module parameters while loading the driver.

Make this new version as the default selection by a new Kconfig choice.

Signed-off-by: Yadi Brar <yadi.brar01@gmail.com>
Signed-off-by: Jassi Brar <jaswinder.singh@linaro.org>
Signed-off-by: Felipe Balbi <balbi@ti.com>
diff --git a/drivers/usb/gadget/audio.c b/drivers/usb/gadget/audio.c
index 33e9327..9889924 100644
--- a/drivers/usb/gadget/audio.c
+++ b/drivers/usb/gadget/audio.c
@@ -14,10 +14,8 @@
 #include <linux/kernel.h>
 #include <linux/utsname.h>
 
-#include "u_uac1.h"
-
 #define DRIVER_DESC		"Linux USB Audio Gadget"
-#define DRIVER_VERSION		"Dec 18, 2008"
+#define DRIVER_VERSION		"Feb 2, 2012"
 
 /*-------------------------------------------------------------------------*/
 
@@ -56,8 +54,13 @@
 	NULL,
 };
 
+#ifdef CONFIG_GADGET_UAC1
+#include "u_uac1.h"
 #include "u_uac1.c"
 #include "f_uac1.c"
+#else
+#include "f_uac2.c"
+#endif
 
 /*-------------------------------------------------------------------------*/
 
@@ -77,9 +80,15 @@
 
 	.bcdUSB =		__constant_cpu_to_le16(0x200),
 
+#ifdef CONFIG_GADGET_UAC1
 	.bDeviceClass =		USB_CLASS_PER_INTERFACE,
 	.bDeviceSubClass =	0,
 	.bDeviceProtocol =	0,
+#else
+	.bDeviceClass =		USB_CLASS_MISC,
+	.bDeviceSubClass =	0x02,
+	.bDeviceProtocol =	0x01,
+#endif
 	/* .bMaxPacketSize0 = f(hardware) */
 
 	/* Vendor and product id defaults change according to what configs
@@ -131,6 +140,9 @@
 	.bConfigurationValue	= 1,
 	/* .iConfiguration = DYNAMIC */
 	.bmAttributes		= USB_CONFIG_ATT_SELFPOWER,
+#ifndef CONFIG_GADGET_UAC1
+	.unbind			= uac2_unbind_config,
+#endif
 };
 
 /*-------------------------------------------------------------------------*/
@@ -180,7 +192,9 @@
 
 static int __exit audio_unbind(struct usb_composite_dev *cdev)
 {
+#ifdef CONFIG_GADGET_UAC1
 	gaudio_cleanup();
+#endif
 	return 0;
 }