Merge branch 'l4t/l4t-r16-r2' into colibri

Conflicts:
	arch/arm/mach-tegra/tegra3_usb_phy.c
	arch/arm/mach-tegra/usb_phy.c
	drivers/usb/gadget/tegra_udc.c
	drivers/usb/otg/Makefile
	drivers/video/tegra/fb.c
	sound/soc/tegra/tegra_pcm.c

7 files changed, 1445 insertions, 56 deletions

diff --git a/drivers/usb/gadget/Kconfig b/drivers/usb/gadget/Kconfig
index 8e051d72d6aa..e7c6ca49ab8e 100644
--- a/drivers/usb/gadget/Kconfig
+++ b/drivers/usb/gadget/Kconfig
@@ -143,7 +143,7 @@ config USB_FSL_USB2
 	tristate "Freescale Highspeed USB DR Peripheral Controller"
 	depends on FSL_SOC || ARCH_MXC || ARCH_TEGRA
 	select USB_GADGET_DUALSPEED
-	select USB_FSL_MPH_DR_OF if OF
+	select USB_FSL_MPH_DR_OF if OF && FSL_SOC
 	help
 	   Some of Freescale PowerPC processors have a High Speed
 	   Dual-Role(DR) USB controller, which supports device mode.
diff --git a/drivers/usb/gadget/Makefile b/drivers/usb/gadget/Makefile
index c8c7c687010d..13f24548cee1 100644
--- a/drivers/usb/gadget/Makefile
+++ b/drivers/usb/gadget/Makefile
@@ -21,6 +21,7 @@ obj-$(CONFIG_USB_ATMEL_USBA)	+= atmel_usba_udc.o
 obj-$(CONFIG_USB_FSL_USB2)	+= fsl_usb2_udc.o
 fsl_usb2_udc-y			:= fsl_udc_core.o
 fsl_usb2_udc-$(CONFIG_ARCH_MXC)	+= fsl_mxc_udc.o
+CFLAGS_tegra_udc.o		= -Werror
 obj-$(CONFIG_USB_TEGRA)		+= tegra_udc.o
 obj-$(CONFIG_USB_M66592)	+= m66592-udc.o
 obj-$(CONFIG_USB_R8A66597)	+= r8a66597-udc.o
diff --git a/drivers/usb/gadget/android.c b/drivers/usb/gadget/android.c
index dbc22802b43c..9f79c267890e 100644
--- a/drivers/usb/gadget/android.c
+++ b/drivers/usb/gadget/android.c
@@ -45,6 +45,7 @@
 #include "epautoconf.c"
 #include "composite.c"
 
+#include "f_audio_source.c"
 #include "f_mass_storage.c"
 #include "u_serial.c"
 #include "f_acm.c"
@@ -649,6 +650,67 @@ static struct android_usb_function accessory_function = {
 	.ctrlrequest	= accessory_function_ctrlrequest,
 };
 
+static int audio_source_function_init(struct android_usb_function *f,
+			struct usb_composite_dev *cdev)
+{
+	struct audio_source_config *config;
+
+	config = kzalloc(sizeof(struct audio_source_config), GFP_KERNEL);
+	if (!config)
+		return -ENOMEM;
+	config->card = -1;
+	config->device = -1;
+	f->config = config;
+	return 0;
+}
+
+static void audio_source_function_cleanup(struct android_usb_function *f)
+{
+	kfree(f->config);
+}
+
+static int audio_source_function_bind_config(struct android_usb_function *f,
+						struct usb_configuration *c)
+{
+	struct audio_source_config *config = f->config;
+
+	return audio_source_bind_config(c, config);
+}
+
+static void audio_source_function_unbind_config(struct android_usb_function *f,
+						struct usb_configuration *c)
+{
+	struct audio_source_config *config = f->config;
+
+	config->card = -1;
+	config->device = -1;
+}
+
+static ssize_t audio_source_pcm_show(struct device *dev,
+		struct device_attribute *attr, char *buf)
+{
+	struct android_usb_function *f = dev_get_drvdata(dev);
+	struct audio_source_config *config = f->config;
+
+	/* print PCM card and device numbers */
+	return sprintf(buf, "%d %d\n", config->card, config->device);
+}
+
+static DEVICE_ATTR(pcm, S_IRUGO | S_IWUSR, audio_source_pcm_show, NULL);
+
+static struct device_attribute *audio_source_function_attributes[] = {
+	&dev_attr_pcm,
+	NULL
+};
+
+static struct android_usb_function audio_source_function = {
+	.name		= "audio_source",
+	.init		= audio_source_function_init,
+	.cleanup	= audio_source_function_cleanup,
+	.bind_config	= audio_source_function_bind_config,
+	.unbind_config	= audio_source_function_unbind_config,
+	.attributes	= audio_source_function_attributes,
+};
 
 static struct android_usb_function *supported_functions[] = {
 	&adb_function,
@@ -658,6 +720,7 @@ static struct android_usb_function *supported_functions[] = {
 	&rndis_function,
 	&mass_storage_function,
 	&accessory_function,
+	&audio_source_function,
 	NULL
 };
 
@@ -1113,6 +1176,11 @@ static void android_disconnect(struct usb_gadget *gadget)
 	unsigned long flags;
 
 	composite_disconnect(gadget);
+	/* accessory HID support can be active while the
+	   accessory function is not actually enabled,
+	   so we need to inform it when we are disconnected.
+	 */
+	acc_disconnect();
 
 	spin_lock_irqsave(&cdev->lock, flags);
 	dev->connected = 0;
diff --git a/drivers/usb/gadget/f_accessory.c b/drivers/usb/gadget/f_accessory.c
index ae65faaf3d77..d248ef98b532 100644
--- a/drivers/usb/gadget/f_accessory.c
+++ b/drivers/usb/gadget/f_accessory.c
@@ -33,6 +33,8 @@
 #include <linux/device.h>
 #include <linux/miscdevice.h>
 
+#include <linux/hid.h>
+#include <linux/hiddev.h>
 #include <linux/usb.h>
 #include <linux/usb/ch9.h>
 #include <linux/usb/f_accessory.h>
@@ -40,7 +42,7 @@
 #define BULK_BUFFER_SIZE    16384
 #define ACC_STRING_SIZE     256
 
-#define PROTOCOL_VERSION    1
+#define PROTOCOL_VERSION    2
 
 /* String IDs */
 #define INTERFACE_STRING_INDEX	0
@@ -49,6 +51,20 @@
 #define TX_REQ_MAX 4
 #define RX_REQ_MAX 2
 
+struct acc_hid_dev {
+	struct list_head	list;
+	struct hid_device *hid;
+	struct acc_dev *dev;
+	/* accessory defined ID */
+	int id;
+	/* HID report descriptor */
+	u8 *report_desc;
+	/* length of HID report descriptor */
+	int report_desc_len;
+	/* number of bytes of report_desc we have received so far */
+	int report_desc_offset;
+};
+
 struct acc_dev {
 	struct usb_function function;
 	struct usb_composite_dev *cdev;
@@ -78,6 +94,8 @@ struct acc_dev {
 	/* set to 1 if we have a pending start request */
 	int start_requested;
 
+	int audio_mode;
+
 	/* synchronize access to our device file */
 	atomic_t open_excl;
 
@@ -87,7 +105,21 @@ struct acc_dev {
 	wait_queue_head_t write_wq;
 	struct usb_request *rx_req[RX_REQ_MAX];
 	int rx_done;
-	struct delayed_work work;
+
+	/* delayed work for handling ACCESSORY_START */
+	struct delayed_work start_work;
+
+	/* worker for registering and unregistering hid devices */
+	struct work_struct hid_work;
+
+	/* list of active HID devices */
+	struct list_head	hid_list;
+
+	/* list of new HID devices to register */
+	struct list_head	new_hid_list;
+
+	/* list of dead HID devices to unregister */
+	struct list_head	dead_hid_list;
 };
 
 static struct usb_interface_descriptor acc_interface_desc = {
@@ -296,7 +328,161 @@ static void acc_complete_set_string(struct usb_ep *ep, struct usb_request *req)
 	}
 }
 
-static int __init create_bulk_endpoints(struct acc_dev *dev,
+static void acc_complete_set_hid_report_desc(struct usb_ep *ep,
+		struct usb_request *req)
+{
+	struct acc_hid_dev *hid = req->context;
+	struct acc_dev *dev = hid->dev;
+	int length = req->actual;
+
+	if (req->status != 0) {
+		pr_err("acc_complete_set_hid_report_desc, err %d\n",
+			req->status);
+		return;
+	}
+
+	memcpy(hid->report_desc + hid->report_desc_offset, req->buf, length);
+	hid->report_desc_offset += length;
+	if (hid->report_desc_offset == hid->report_desc_len) {
+		/* After we have received the entire report descriptor
+		 * we schedule work to initialize the HID device
+		 */
+		schedule_work(&dev->hid_work);
+	}
+}
+
+static void acc_complete_send_hid_event(struct usb_ep *ep,
+		struct usb_request *req)
+{
+	struct acc_hid_dev *hid = req->context;
+	int length = req->actual;
+
+	if (req->status != 0) {
+		pr_err("acc_complete_send_hid_event, err %d\n", req->status);
+		return;
+	}
+
+	hid_report_raw_event(hid->hid, HID_INPUT_REPORT, req->buf, length, 1);
+}
+
+static int acc_hid_parse(struct hid_device *hid)
+{
+	struct acc_hid_dev *hdev = hid->driver_data;
+
+	hid_parse_report(hid, hdev->report_desc, hdev->report_desc_len);
+	return 0;
+}
+
+static int acc_hid_start(struct hid_device *hid)
+{
+	return 0;
+}
+
+static void acc_hid_stop(struct hid_device *hid)
+{
+}
+
+static int acc_hid_open(struct hid_device *hid)
+{
+	return 0;
+}
+
+static void acc_hid_close(struct hid_device *hid)
+{
+}
+
+static struct hid_ll_driver acc_hid_ll_driver = {
+	.parse = acc_hid_parse,
+	.start = acc_hid_start,
+	.stop = acc_hid_stop,
+	.open = acc_hid_open,
+	.close = acc_hid_close,
+};
+
+static struct acc_hid_dev *acc_hid_new(struct acc_dev *dev,
+		int id, int desc_len)
+{
+	struct acc_hid_dev *hdev;
+
+	hdev = kzalloc(sizeof(*hdev), GFP_ATOMIC);
+	if (!hdev)
+		return NULL;
+	hdev->report_desc = kzalloc(desc_len, GFP_ATOMIC);
+	if (!hdev->report_desc) {
+		kfree(hdev);
+		return NULL;
+	}
+	hdev->dev = dev;
+	hdev->id = id;
+	hdev->report_desc_len = desc_len;
+
+	return hdev;
+}
+
+static struct acc_hid_dev *acc_hid_get(struct list_head *list, int id)
+{
+	struct acc_hid_dev *hid;
+
+	list_for_each_entry(hid, list, list) {
+		if (hid->id == id)
+			return hid;
+	}
+	return NULL;
+}
+
+static int acc_register_hid(struct acc_dev *dev, int id, int desc_length)
+{
+	struct acc_hid_dev *hid;
+	unsigned long flags;
+
+	/* report descriptor length must be > 0 */
+	if (desc_length <= 0)
+		return -EINVAL;
+
+	spin_lock_irqsave(&dev->lock, flags);
+	/* replace HID if one already exists with this ID */
+	hid = acc_hid_get(&dev->hid_list, id);
+	if (!hid)
+		hid = acc_hid_get(&dev->new_hid_list, id);
+	if (hid)
+		list_move(&hid->list, &dev->dead_hid_list);
+
+	hid = acc_hid_new(dev, id, desc_length);
+	if (!hid) {
+		spin_unlock_irqrestore(&dev->lock, flags);
+		return -ENOMEM;
+	}
+
+	list_add(&hid->list, &dev->new_hid_list);
+	spin_unlock_irqrestore(&dev->lock, flags);
+
+	/* schedule work to register the HID device */
+	schedule_work(&dev->hid_work);
+	return 0;
+}
+
+static int acc_unregister_hid(struct acc_dev *dev, int id)
+{
+	struct acc_hid_dev *hid;
+	unsigned long flags;
+
+	spin_lock_irqsave(&dev->lock, flags);
+	hid = acc_hid_get(&dev->hid_list, id);
+	if (!hid)
+		hid = acc_hid_get(&dev->new_hid_list, id);
+	if (!hid) {
+		spin_unlock_irqrestore(&dev->lock, flags);
+		return -EINVAL;
+	}
+
+	list_move(&hid->list, &dev->dead_hid_list);
+	spin_unlock_irqrestore(&dev->lock, flags);
+
+	schedule_work(&dev->hid_work);
+	return 0;
+}
+
+static int create_bulk_endpoints(struct acc_dev *dev,
 				struct usb_endpoint_descriptor *in_desc,
 				struct usb_endpoint_descriptor *out_desc)
 {
@@ -353,7 +539,7 @@ static int __init create_bulk_endpoints(struct acc_dev *dev,
 	return 0;
 
 fail:
-	printk(KERN_ERR "acc_bind() could not allocate requests\n");
+	pr_err("acc_bind() could not allocate requests\n");
 	while ((req = req_get(dev, &dev->tx_idle)))
 		acc_request_free(req, dev->ep_in);
 	for (i = 0; i < RX_REQ_MAX; i++)
@@ -510,6 +696,8 @@ static long acc_ioctl(struct file *fp, unsigned code, unsigned long value)
 		break;
 	case ACCESSORY_IS_START_REQUESTED:
 		return dev->start_requested;
+	case ACCESSORY_GET_AUDIO_MODE:
+		return dev->audio_mode;
 	}
 	if (!src)
 		return -EINVAL;
@@ -540,7 +728,7 @@ static int acc_release(struct inode *ip, struct file *fp)
 	return 0;
 }
 
-/* file operations for /dev/acc_usb */
+/* file operations for /dev/usb_accessory */
 static const struct file_operations acc_fops = {
 	.owner = THIS_MODULE,
 	.read = acc_read,
@@ -550,23 +738,47 @@ static const struct file_operations acc_fops = {
 	.release = acc_release,
 };
 
+static int acc_hid_probe(struct hid_device *hdev,
+		const struct hid_device_id *id)
+{
+	int ret;
+
+	ret = hid_parse(hdev);
+	if (ret)
+		return ret;
+	return hid_hw_start(hdev, HID_CONNECT_DEFAULT);
+}
+
 static struct miscdevice acc_device = {
 	.minor = MISC_DYNAMIC_MINOR,
 	.name = "usb_accessory",
 	.fops = &acc_fops,
 };
 
+static const struct hid_device_id acc_hid_table[] = {
+	{ HID_USB_DEVICE(HID_ANY_ID, HID_ANY_ID) },
+	{ }
+};
+
+static struct hid_driver acc_hid_driver = {
+	.name = "USB accessory",
+	.id_table = acc_hid_table,
+	.probe = acc_hid_probe,
+};
 
 static int acc_ctrlrequest(struct usb_composite_dev *cdev,
 				const struct usb_ctrlrequest *ctrl)
 {
 	struct acc_dev	*dev = _acc_dev;
 	int	value = -EOPNOTSUPP;
+	struct acc_hid_dev *hid;
+	int offset;
 	u8 b_requestType = ctrl->bRequestType;
 	u8 b_request = ctrl->bRequest;
 	u16	w_index = le16_to_cpu(ctrl->wIndex);
 	u16	w_value = le16_to_cpu(ctrl->wValue);
 	u16	w_length = le16_to_cpu(ctrl->wLength);
+	unsigned long flags;
 
 /*
 	printk(KERN_INFO "acc_ctrlrequest "
@@ -579,20 +791,56 @@ static int acc_ctrlrequest(struct usb_composite_dev *cdev,
 		if (b_request == ACCESSORY_START) {
 			dev->start_requested = 1;
 			schedule_delayed_work(
-				&dev->work, msecs_to_jiffies(10));
+				&dev->start_work, msecs_to_jiffies(10));
 			value = 0;
 		} else if (b_request == ACCESSORY_SEND_STRING) {
 			dev->string_index = w_index;
 			cdev->gadget->ep0->driver_data = dev;
 			cdev->req->complete = acc_complete_set_string;
 			value = w_length;
+		} else if (b_request == ACCESSORY_SET_AUDIO_MODE &&
+				w_index == 0 && w_length == 0) {
+			dev->audio_mode = w_value;
+			value = 0;
+		} else if (b_request == ACCESSORY_REGISTER_HID) {
+			value = acc_register_hid(dev, w_value, w_index);
+		} else if (b_request == ACCESSORY_UNREGISTER_HID) {
+			value = acc_unregister_hid(dev, w_value);
+		} else if (b_request == ACCESSORY_SET_HID_REPORT_DESC) {
+			spin_lock_irqsave(&dev->lock, flags);
+			hid = acc_hid_get(&dev->new_hid_list, w_value);
+			spin_unlock_irqrestore(&dev->lock, flags);
+			if (!hid) {
+				value = -EINVAL;
+				goto err;
+			}
+			offset = w_index;
+			if (offset != hid->report_desc_offset
+				|| offset + w_length > hid->report_desc_len) {
+				value = -EINVAL;
+				goto err;
+			}
+			cdev->req->context = hid;
+			cdev->req->complete = acc_complete_set_hid_report_desc;
+			value = w_length;
+		} else if (b_request == ACCESSORY_SEND_HID_EVENT) {
+			spin_lock_irqsave(&dev->lock, flags);
+			hid = acc_hid_get(&dev->hid_list, w_value);
+			spin_unlock_irqrestore(&dev->lock, flags);
+			if (!hid) {
+				value = -EINVAL;
+				goto err;
+			}
+			cdev->req->context = hid;
+			cdev->req->complete = acc_complete_send_hid_event;
+			value = w_length;
 		}
 	} else if (b_requestType == (USB_DIR_IN | USB_TYPE_VENDOR)) {
 		if (b_request == ACCESSORY_GET_PROTOCOL) {
 			*((u16 *)cdev->req->buf) = PROTOCOL_VERSION;
 			value = sizeof(u16);
 
-			/* clear any strings left over from a previous session */
+			/* clear strings left over from a previous session */
 			memset(dev->manufacturer, 0, sizeof(dev->manufacturer));
 			memset(dev->model, 0, sizeof(dev->model));
 			memset(dev->description, 0, sizeof(dev->description));
@@ -600,6 +848,7 @@ static int acc_ctrlrequest(struct usb_composite_dev *cdev,
 			memset(dev->uri, 0, sizeof(dev->uri));
 			memset(dev->serial, 0, sizeof(dev->serial));
 			dev->start_requested = 0;
+			dev->audio_mode = 0;
 		}
 	}
 
@@ -612,6 +861,7 @@ static int acc_ctrlrequest(struct usb_composite_dev *cdev,
 				__func__);
 	}
 
+err:
 	if (value == -EOPNOTSUPP)
 		VDBG(cdev,
 			"unknown class-specific control req "
@@ -631,6 +881,10 @@ acc_function_bind(struct usb_configuration *c, struct usb_function *f)
 
 	DBG(cdev, "acc_function_bind dev: %p\n", dev);
 
+	ret = hid_register_driver(&acc_hid_driver);
+	if (ret)
+		return ret;
+
 	dev->start_requested = 0;
 
 	/* allocate interface ID(s) */
@@ -660,6 +914,36 @@ acc_function_bind(struct usb_configuration *c, struct usb_function *f)
 }
 
 static void
+kill_all_hid_devices(struct acc_dev *dev)
+{
+	struct acc_hid_dev *hid;
+	struct list_head *entry, *temp;
+	unsigned long flags;
+
+	spin_lock_irqsave(&dev->lock, flags);
+	list_for_each_safe(entry, temp, &dev->hid_list) {
+		hid = list_entry(entry, struct acc_hid_dev, list);
+		list_del(&hid->list);
+		list_add(&hid->list, &dev->dead_hid_list);
+	}
+	list_for_each_safe(entry, temp, &dev->new_hid_list) {
+		hid = list_entry(entry, struct acc_hid_dev, list);
+		list_del(&hid->list);
+		list_add(&hid->list, &dev->dead_hid_list);
+	}
+	spin_unlock_irqrestore(&dev->lock, flags);
+
+	schedule_work(&dev->hid_work);
+}
+
+static void
+acc_hid_unbind(struct acc_dev *dev)
+{
+	hid_unregister_driver(&acc_hid_driver);
+	kill_all_hid_devices(dev);
+}
+
+static void
 acc_function_unbind(struct usb_configuration *c, struct usb_function *f)
 {
 	struct acc_dev	*dev = func_to_dev(f);
@@ -670,14 +954,104 @@ acc_function_unbind(struct usb_configuration *c, struct usb_function *f)
 		acc_request_free(req, dev->ep_in);
 	for (i = 0; i < RX_REQ_MAX; i++)
 		acc_request_free(dev->rx_req[i], dev->ep_out);
+
+	acc_hid_unbind(dev);
 }
 
-static void acc_work(struct work_struct *data)
+static void acc_start_work(struct work_struct *data)
 {
 	char *envp[2] = { "ACCESSORY=START", NULL };
 	kobject_uevent_env(&acc_device.this_device->kobj, KOBJ_CHANGE, envp);
 }
 
+static int acc_hid_init(struct acc_hid_dev *hdev)
+{
+	struct hid_device *hid;
+	int ret;
+
+	hid = hid_allocate_device();
+	if (IS_ERR(hid))
+		return PTR_ERR(hid);
+
+	hid->ll_driver = &acc_hid_ll_driver;
+	hid->dev.parent = acc_device.this_device;
+
+	hid->bus = BUS_USB;
+	hid->vendor = HID_ANY_ID;
+	hid->product = HID_ANY_ID;
+	hid->driver_data = hdev;
+	ret = hid_add_device(hid);
+	if (ret) {
+		pr_err("can't add hid device: %d\n", ret);
+		hid_destroy_device(hid);
+		return ret;
+	}
+
+	hdev->hid = hid;
+	return 0;
+}
+
+static void acc_hid_delete(struct acc_hid_dev *hid)
+{
+	kfree(hid->report_desc);
+	kfree(hid);
+}
+
+static void acc_hid_work(struct work_struct *data)
+{
+	struct acc_dev *dev = _acc_dev;
+	struct list_head	*entry, *temp;
+	struct acc_hid_dev *hid;
+	struct list_head	new_list, dead_list;
+	unsigned long flags;
+
+	INIT_LIST_HEAD(&new_list);
+
+	spin_lock_irqsave(&dev->lock, flags);
+
+	/* copy hids that are ready for initialization to new_list */
+	list_for_each_safe(entry, temp, &dev->new_hid_list) {
+		hid = list_entry(entry, struct acc_hid_dev, list);
+		if (hid->report_desc_offset == hid->report_desc_len)
+			list_move(&hid->list, &new_list);
+	}
+
+	if (list_empty(&dev->dead_hid_list)) {
+		INIT_LIST_HEAD(&dead_list);
+	} else {
+		/* move all of dev->dead_hid_list to dead_list */
+		dead_list.prev = dev->dead_hid_list.prev;
+		dead_list.next = dev->dead_hid_list.next;
+		dead_list.next->prev = &dead_list;
+		dead_list.prev->next = &dead_list;
+		INIT_LIST_HEAD(&dev->dead_hid_list);
+	}
+
+	spin_unlock_irqrestore(&dev->lock, flags);
+
+	/* register new HID devices */
+	list_for_each_safe(entry, temp, &new_list) {
+		hid = list_entry(entry, struct acc_hid_dev, list);
+		if (acc_hid_init(hid)) {
+			pr_err("can't add HID device %p\n", hid);
+			acc_hid_delete(hid);
+		} else {
+			spin_lock_irqsave(&dev->lock, flags);
+			list_move(&hid->list, &dev->hid_list);
+			spin_unlock_irqrestore(&dev->lock, flags);
+		}
+	}
+
+	/* remove dead HID devices */
+	list_for_each_safe(entry, temp, &dead_list) {
+		hid = list_entry(entry, struct acc_hid_dev, list);
+		list_del(&hid->list);
+		if (hid->hid)
+			hid_destroy_device(hid->hid);
+		acc_hid_delete(hid);
+	}
+}
+
 static int acc_function_set_alt(struct usb_function *f,
 		unsigned intf, unsigned alt)
 {
@@ -763,7 +1137,11 @@ static int acc_setup(void)
 	init_waitqueue_head(&dev->write_wq);
 	atomic_set(&dev->open_excl, 0);
 	INIT_LIST_HEAD(&dev->tx_idle);
-	INIT_DELAYED_WORK(&dev->work, acc_work);
+	INIT_LIST_HEAD(&dev->hid_list);
+	INIT_LIST_HEAD(&dev->new_hid_list);
+	INIT_LIST_HEAD(&dev->dead_hid_list);
+	INIT_DELAYED_WORK(&dev->start_work, acc_start_work);
+	INIT_WORK(&dev->hid_work, acc_hid_work);
 
 	/* _acc_dev must be set before calling usb_gadget_register_driver */
 	_acc_dev = dev;
@@ -776,10 +1154,16 @@ static int acc_setup(void)
 
 err:
 	kfree(dev);
-	printk(KERN_ERR "USB accessory gadget driver failed to initialize\n");
+	pr_err("USB accessory gadget driver failed to initialize\n");
 	return ret;
 }
 
+static void acc_disconnect(void)
+{
+	/* unregister all HID devices if USB is disconnected */
+	kill_all_hid_devices(_acc_dev);
+}
+
 static void acc_cleanup(void)
 {
 	misc_deregister(&acc_device);
diff --git a/drivers/usb/gadget/f_audio_source.c b/drivers/usb/gadget/f_audio_source.c
new file mode 100644
index 000000000000..3ba7d7569b12
--- /dev/null
+++ b/drivers/usb/gadget/f_audio_source.c
@@ -0,0 +1,827 @@
+/*
+ * Gadget Function Driver for USB audio source device
+ *
+ * Copyright (C) 2012 Google, Inc.
+ *
+ * This software is licensed under the terms of the GNU General Public
+ * License version 2, as published by the Free Software Foundation, and
+ * may be copied, distributed, and modified under those terms.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ */
+
+#include <linux/device.h>
+#include <linux/usb/audio.h>
+#include <linux/wait.h>
+#include <sound/core.h>
+#include <sound/initval.h>
+#include <sound/pcm.h>
+
+#define SAMPLE_RATE 44100
+/* Each frame is two 16 bit integers (one per channel) */
+#define BYTES_PER_FRAME 4
+#define FRAMES_PER_MSEC (SAMPLE_RATE / 1000)
+
+#define IN_EP_MAX_PACKET_SIZE 256
+
+/* Number of requests to allocate */
+#define IN_EP_REQ_COUNT 4
+
+#define AUDIO_AC_INTERFACE	0
+#define AUDIO_AS_INTERFACE	1
+#define AUDIO_NUM_INTERFACES	2
+
+/* B.3.1  Standard AC Interface Descriptor */
+static struct usb_interface_descriptor ac_interface_desc = {
+	.bLength =		USB_DT_INTERFACE_SIZE,
+	.bDescriptorType =	USB_DT_INTERFACE,
+	.bNumEndpoints =	0,
+	.bInterfaceClass =	USB_CLASS_AUDIO,
+	.bInterfaceSubClass =	USB_SUBCLASS_AUDIOCONTROL,
+};
+
+DECLARE_UAC_AC_HEADER_DESCRIPTOR(2);
+
+#define UAC_DT_AC_HEADER_LENGTH	UAC_DT_AC_HEADER_SIZE(AUDIO_NUM_INTERFACES)
+/* 1 input terminal, 1 output terminal and 1 feature unit */
+#define UAC_DT_TOTAL_LENGTH (UAC_DT_AC_HEADER_LENGTH \
+	+ UAC_DT_INPUT_TERMINAL_SIZE + UAC_DT_OUTPUT_TERMINAL_SIZE \
+	+ UAC_DT_FEATURE_UNIT_SIZE(0))
+/* B.3.2  Class-Specific AC Interface Descriptor */
+static struct uac1_ac_header_descriptor_2 ac_header_desc = {
+	.bLength =		UAC_DT_AC_HEADER_LENGTH,
+	.bDescriptorType =	USB_DT_CS_INTERFACE,
+	.bDescriptorSubtype =	UAC_HEADER,
+	.bcdADC =		__constant_cpu_to_le16(0x0100),
+	.wTotalLength =		__constant_cpu_to_le16(UAC_DT_TOTAL_LENGTH),
+	.bInCollection =	AUDIO_NUM_INTERFACES,
+	.baInterfaceNr = {
+		[0] =		AUDIO_AC_INTERFACE,
+		[1] =		AUDIO_AS_INTERFACE,
+	}
+};
+
+#define INPUT_TERMINAL_ID	1
+static struct uac_input_terminal_descriptor input_terminal_desc = {
+	.bLength =		UAC_DT_INPUT_TERMINAL_SIZE,
+	.bDescriptorType =	USB_DT_CS_INTERFACE,
+	.bDescriptorSubtype =	UAC_INPUT_TERMINAL,
+	.bTerminalID =		INPUT_TERMINAL_ID,
+	.wTerminalType =	UAC_INPUT_TERMINAL_MICROPHONE,
+	.bAssocTerminal =	0,
+	.wChannelConfig =	0x3,
+};
+
+DECLARE_UAC_FEATURE_UNIT_DESCRIPTOR(0);
+
+#define FEATURE_UNIT_ID		2
+static struct uac_feature_unit_descriptor_0 feature_unit_desc = {
+	.bLength		= UAC_DT_FEATURE_UNIT_SIZE(0),
+	.bDescriptorType	= USB_DT_CS_INTERFACE,
+	.bDescriptorSubtype	= UAC_FEATURE_UNIT,
+	.bUnitID		= FEATURE_UNIT_ID,
+	.bSourceID		= INPUT_TERMINAL_ID,
+	.bControlSize		= 2,
+};
+
+#define OUTPUT_TERMINAL_ID	3
+static struct uac1_output_terminal_descriptor output_terminal_desc = {
+	.bLength		= UAC_DT_OUTPUT_TERMINAL_SIZE,
+	.bDescriptorType	= USB_DT_CS_INTERFACE,
+	.bDescriptorSubtype	= UAC_OUTPUT_TERMINAL,
+	.bTerminalID		= OUTPUT_TERMINAL_ID,
+	.wTerminalType		= UAC_TERMINAL_STREAMING,
+	.bAssocTerminal		= FEATURE_UNIT_ID,
+	.bSourceID		= FEATURE_UNIT_ID,
+};
+
+/* B.4.1  Standard AS Interface Descriptor */
+static struct usb_interface_descriptor as_interface_alt_0_desc = {
+	.bLength =		USB_DT_INTERFACE_SIZE,
+	.bDescriptorType =	USB_DT_INTERFACE,
+	.bAlternateSetting =	0,
+	.bNumEndpoints =	0,
+	.bInterfaceClass =	USB_CLASS_AUDIO,
+	.bInterfaceSubClass =	USB_SUBCLASS_AUDIOSTREAMING,
+};
+
+static struct usb_interface_descriptor as_interface_alt_1_desc = {
+	.bLength =		USB_DT_INTERFACE_SIZE,
+	.bDescriptorType =	USB_DT_INTERFACE,
+	.bAlternateSetting =	1,
+	.bNumEndpoints =	1,
+	.bInterfaceClass =	USB_CLASS_AUDIO,
+	.bInterfaceSubClass =	USB_SUBCLASS_AUDIOSTREAMING,
+};
+
+/* B.4.2  Class-Specific AS Interface Descriptor */
+static struct uac1_as_header_descriptor as_header_desc = {
+	.bLength =		UAC_DT_AS_HEADER_SIZE,
+	.bDescriptorType =	USB_DT_CS_INTERFACE,
+	.bDescriptorSubtype =	UAC_AS_GENERAL,
+	.bTerminalLink =	INPUT_TERMINAL_ID,
+	.bDelay =		1,
+	.wFormatTag =		UAC_FORMAT_TYPE_I_PCM,
+};
+
+DECLARE_UAC_FORMAT_TYPE_I_DISCRETE_DESC(1);
+
+static struct uac_format_type_i_discrete_descriptor_1 as_type_i_desc = {
+	.bLength =		UAC_FORMAT_TYPE_I_DISCRETE_DESC_SIZE(1),
+	.bDescriptorType =	USB_DT_CS_INTERFACE,
+	.bDescriptorSubtype =	UAC_FORMAT_TYPE,
+	.bFormatType =		UAC_FORMAT_TYPE_I,
+	.bSubframeSize =	2,
+	.bBitResolution =	16,
+	.bSamFreqType =		1,
+};
+
+/* Standard ISO IN Endpoint Descriptor for highspeed */
+static struct usb_endpoint_descriptor hs_as_in_ep_desc  = {
+	.bLength =		USB_DT_ENDPOINT_AUDIO_SIZE,
+	.bDescriptorType =	USB_DT_ENDPOINT,
+	.bEndpointAddress =	USB_DIR_IN,
+	.bmAttributes =		USB_ENDPOINT_SYNC_SYNC
+				| USB_ENDPOINT_XFER_ISOC,
+	.wMaxPacketSize =	__constant_cpu_to_le16(IN_EP_MAX_PACKET_SIZE),
+	.bInterval =		4, /* poll 1 per millisecond */
+};
+
+/* Standard ISO IN Endpoint Descriptor for highspeed */
+static struct usb_endpoint_descriptor fs_as_in_ep_desc  = {
+	.bLength =		USB_DT_ENDPOINT_AUDIO_SIZE,
+	.bDescriptorType =	USB_DT_ENDPOINT,
+	.bEndpointAddress =	USB_DIR_IN,
+	.bmAttributes =		USB_ENDPOINT_SYNC_SYNC
+				| USB_ENDPOINT_XFER_ISOC,
+	.wMaxPacketSize =	__constant_cpu_to_le16(IN_EP_MAX_PACKET_SIZE),
+	.bInterval =		1, /* poll 1 per millisecond */
+};
+
+/* Class-specific AS ISO OUT Endpoint Descriptor */
+static struct uac_iso_endpoint_descriptor as_iso_in_desc = {
+	.bLength =		UAC_ISO_ENDPOINT_DESC_SIZE,
+	.bDescriptorType =	USB_DT_CS_ENDPOINT,
+	.bDescriptorSubtype =	UAC_EP_GENERAL,
+	.bmAttributes =		1,
+	.bLockDelayUnits =	1,
+	.wLockDelay =		__constant_cpu_to_le16(1),
+};
+
+static struct usb_descriptor_header *hs_audio_desc[] = {
+	(struct usb_descriptor_header *)&ac_interface_desc,
+	(struct usb_descriptor_header *)&ac_header_desc,
+
+	(struct usb_descriptor_header *)&input_terminal_desc,
+	(struct usb_descriptor_header *)&output_terminal_desc,
+	(struct usb_descriptor_header *)&feature_unit_desc,
+
+	(struct usb_descriptor_header *)&as_interface_alt_0_desc,
+	(struct usb_descriptor_header *)&as_interface_alt_1_desc,
+	(struct usb_descriptor_header *)&as_header_desc,
+
+	(struct usb_descriptor_header *)&as_type_i_desc,
+
+	(struct usb_descriptor_header *)&hs_as_in_ep_desc,
+	(struct usb_descriptor_header *)&as_iso_in_desc,
+	NULL,
+};
+
+static struct usb_descriptor_header *fs_audio_desc[] = {
+	(struct usb_descriptor_header *)&ac_interface_desc,
+	(struct usb_descriptor_header *)&ac_header_desc,
+
+	(struct usb_descriptor_header *)&input_terminal_desc,
+	(struct usb_descriptor_header *)&output_terminal_desc,
+	(struct usb_descriptor_header *)&feature_unit_desc,
+
+	(struct usb_descriptor_header *)&as_interface_alt_0_desc,
+	(struct usb_descriptor_header *)&as_interface_alt_1_desc,
+	(struct usb_descriptor_header *)&as_header_desc,
+
+	(struct usb_descriptor_header *)&as_type_i_desc,
+
+	(struct usb_descriptor_header *)&fs_as_in_ep_desc,
+	(struct usb_descriptor_header *)&as_iso_in_desc,
+	NULL,
+};
+
+static struct snd_pcm_hardware audio_hw_info = {
+	.info =			SNDRV_PCM_INFO_MMAP |
+				SNDRV_PCM_INFO_MMAP_VALID |
+				SNDRV_PCM_INFO_BATCH |
+				SNDRV_PCM_INFO_INTERLEAVED |
+				SNDRV_PCM_INFO_BLOCK_TRANSFER,
+
+	.formats		= SNDRV_PCM_FMTBIT_S16_LE,
+	.channels_min		= 2,
+	.channels_max		= 2,
+	.rate_min		= SAMPLE_RATE,
+	.rate_max		= SAMPLE_RATE,
+
+	.buffer_bytes_max =	1024 * 1024,
+	.period_bytes_min =	64,
+	.period_bytes_max =	512 * 1024,
+	.periods_min =		2,
+	.periods_max =		1024,
+};
+
+/*-------------------------------------------------------------------------*/
+
+struct audio_source_config {
+	int	card;
+	int	device;
+};
+
+struct audio_dev {
+	struct usb_function		func;
+	struct snd_card			*card;
+	struct snd_pcm			*pcm;
+	struct snd_pcm_substream *substream;
+
+	struct list_head		idle_reqs;
+	struct usb_ep			*in_ep;
+	struct usb_endpoint_descriptor	*in_desc;
+
+	spinlock_t			lock;
+
+	/* beginning, end and current position in our buffer */
+	void				*buffer_start;
+	void				*buffer_end;
+	void				*buffer_pos;
+
+	/* byte size of a "period" */
+	unsigned int			period;
+	/* bytes sent since last call to snd_pcm_period_elapsed */
+	unsigned int			period_offset;
+	/* time we started playing */
+	ktime_t				start_time;
+	/* number of frames sent since start_time */
+	s64				frames_sent;
+};
+
+static inline struct audio_dev *func_to_audio(struct usb_function *f)
+{
+	return container_of(f, struct audio_dev, func);
+}
+
+/*-------------------------------------------------------------------------*/
+
+static struct usb_request *audio_request_new(struct usb_ep *ep, int buffer_size)
+{
+	struct usb_request *req = usb_ep_alloc_request(ep, GFP_KERNEL);
+	if (!req)
+		return NULL;
+
+	req->buf = kmalloc(buffer_size, GFP_KERNEL);
+	if (!req->buf) {
+		usb_ep_free_request(ep, req);
+		return NULL;
+	}
+	req->length = buffer_size;
+	return req;
+}
+
+static void audio_request_free(struct usb_request *req, struct usb_ep *ep)
+{
+	if (req) {
+		kfree(req->buf);
+		usb_ep_free_request(ep, req);
+	}
+}
+
+static void audio_req_put(struct audio_dev *audio, struct usb_request *req)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&audio->lock, flags);
+	list_add_tail(&req->list, &audio->idle_reqs);
+	spin_unlock_irqrestore(&audio->lock, flags);
+}
+
+static struct usb_request *audio_req_get(struct audio_dev *audio)
+{
+	unsigned long flags;
+	struct usb_request *req;
+
+	spin_lock_irqsave(&audio->lock, flags);
+	if (list_empty(&audio->idle_reqs)) {
+		req = 0;
+	} else {
+		req = list_first_entry(&audio->idle_reqs, struct usb_request,
+				list);
+		list_del(&req->list);
+	}
+	spin_unlock_irqrestore(&audio->lock, flags);
+	return req;
+}
+
+/* send the appropriate number of packets to match our bitrate */
+static void audio_send(struct audio_dev *audio)
+{
+	struct snd_pcm_runtime *runtime;
+	struct usb_request *req;
+	int length, length1, length2, ret;
+	s64 msecs;
+	s64 frames;
+	ktime_t now;
+
+	/* audio->substream will be null if we have been closed */
+	if (!audio->substream)
+		return;
+	/* audio->buffer_pos will be null if we have been stopped */
+	if (!audio->buffer_pos)
+		return;
+
+	runtime = audio->substream->runtime;
+
+	/* compute number of frames to send */
+	now = ktime_get();
+	msecs = ktime_to_ns(now) - ktime_to_ns(audio->start_time);
+	do_div(msecs, 1000000);
+	frames = msecs * SAMPLE_RATE;
+	do_div(frames, 1000);
+
+	/* Readjust our frames_sent if we fall too far behind.
+	 * If we get too far behind it is better to drop some frames than
+	 * to keep sending data too fast in an attempt to catch up.
+	 */
+	if (frames - audio->frames_sent > 10 * FRAMES_PER_MSEC)
+		audio->frames_sent = frames - FRAMES_PER_MSEC;
+
+	frames -= audio->frames_sent;
+
+	/* We need to send something to keep the pipeline going */
+	if (frames <= 0)
+		frames = FRAMES_PER_MSEC;
+
+	while (frames > 0) {
+		req = audio_req_get(audio);
+		if (!req)
+			break;
+
+		length = frames_to_bytes(runtime, frames);
+		if (length > IN_EP_MAX_PACKET_SIZE)
+			length = IN_EP_MAX_PACKET_SIZE;
+
+		if (audio->buffer_pos + length > audio->buffer_end)
+			length1 = audio->buffer_end - audio->buffer_pos;
+		else
+			length1 = length;
+		memcpy(req->buf, audio->buffer_pos, length1);
+		if (length1 < length) {
+			/* Wrap around and copy remaining length
+			 * at beginning of buffer.
+			 */
+			length2 = length - length1;
+			memcpy(req->buf + length1, audio->buffer_start,
+					length2);
+			audio->buffer_pos = audio->buffer_start + length2;
+		} else {
+			audio->buffer_pos += length1;
+			if (audio->buffer_pos >= audio->buffer_end)
+				audio->buffer_pos = audio->buffer_start;
+		}
+
+		req->length = length;
+		ret = usb_ep_queue(audio->in_ep, req, GFP_ATOMIC);
+		if (ret < 0) {
+			pr_err("usb_ep_queue failed ret: %d\n", ret);
+			audio_req_put(audio, req);
+			break;
+		}
+
+		frames -= bytes_to_frames(runtime, length);
+		audio->frames_sent += bytes_to_frames(runtime, length);
+	}
+}
+
+static void audio_control_complete(struct usb_ep *ep, struct usb_request *req)
+{
+	/* nothing to do here */
+}
+
+static void audio_data_complete(struct usb_ep *ep, struct usb_request *req)
+{
+	struct audio_dev *audio = req->context;
+
+	pr_debug("audio_data_complete req->status %d req->actual %d\n",
+		req->status, req->actual);
+
+	audio_req_put(audio, req);
+
+	if (!audio->buffer_start)
+		return;
+
+	audio->period_offset += req->actual;
+	if (audio->period_offset >= audio->period) {
+		snd_pcm_period_elapsed(audio->substream);
+		audio->period_offset = 0;
+	}
+	audio_send(audio);
+}
+
+static int audio_set_endpoint_req(struct usb_function *f,
+		const struct usb_ctrlrequest *ctrl)
+{
+	int value = -EOPNOTSUPP;
+	u16 ep = le16_to_cpu(ctrl->wIndex);
+	u16 len = le16_to_cpu(ctrl->wLength);
+	u16 w_value = le16_to_cpu(ctrl->wValue);
+
+	pr_debug("bRequest 0x%x, w_value 0x%04x, len %d, endpoint %d\n",
+			ctrl->bRequest, w_value, len, ep);
+
+	switch (ctrl->bRequest) {
+	case UAC_SET_CUR:
+	case UAC_SET_MIN:
+	case UAC_SET_MAX:
+	case UAC_SET_RES:
+		value = len;
+		break;
+	default:
+		break;
+	}
+
+	return value;
+}
+
+static int audio_get_endpoint_req(struct usb_function *f,
+		const struct usb_ctrlrequest *ctrl)
+{
+	struct usb_composite_dev *cdev = f->config->cdev;
+	int value = -EOPNOTSUPP;
+	u8 ep = ((le16_to_cpu(ctrl->wIndex) >> 8) & 0xFF);
+	u16 len = le16_to_cpu(ctrl->wLength);
+	u16 w_value = le16_to_cpu(ctrl->wValue);
+	u8 *buf = cdev->req->buf;
+
+	pr_debug("bRequest 0x%x, w_value 0x%04x, len %d, endpoint %d\n",
+			ctrl->bRequest, w_value, len, ep);
+
+	if (w_value == UAC_EP_CS_ATTR_SAMPLE_RATE << 8) {
+		switch (ctrl->bRequest) {
+		case UAC_GET_CUR:
+		case UAC_GET_MIN:
+		case UAC_GET_MAX:
+		case UAC_GET_RES:
+			/* return our sample rate */
+			buf[0] = (u8)SAMPLE_RATE;
+			buf[1] = (u8)(SAMPLE_RATE >> 8);
+			buf[2] = (u8)(SAMPLE_RATE >> 16);
+			value = 3;
+			break;
+		default:
+			break;
+		}
+	}
+
+	return value;
+}
+
+static int
+audio_setup(struct usb_function *f, const struct usb_ctrlrequest *ctrl)
+{
+	struct usb_composite_dev *cdev = f->config->cdev;
+	struct usb_request *req = cdev->req;
+	int value = -EOPNOTSUPP;
+	u16 w_index = le16_to_cpu(ctrl->wIndex);
+	u16 w_value = le16_to_cpu(ctrl->wValue);
+	u16 w_length = le16_to_cpu(ctrl->wLength);
+
+	/* composite driver infrastructure handles everything; interface
+	 * activation uses set_alt().
+	 */
+	switch (ctrl->bRequestType) {
+	case USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_ENDPOINT:
+		value = audio_set_endpoint_req(f, ctrl);
+		break;
+
+	case USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_ENDPOINT:
+		value = audio_get_endpoint_req(f, ctrl);
+		break;
+	}
+
+	/* respond with data transfer or status phase? */
+	if (value >= 0) {
+		pr_debug("audio req%02x.%02x v%04x i%04x l%d\n",
+			ctrl->bRequestType, ctrl->bRequest,
+			w_value, w_index, w_length);
+		req->zero = 0;
+		req->length = value;
+		req->complete = audio_control_complete;
+		value = usb_ep_queue(cdev->gadget->ep0, req, GFP_ATOMIC);
+		if (value < 0)
+			pr_err("audio response on err %d\n", value);
+	}
+
+	/* device either stalls (value < 0) or reports success */
+	return value;
+}
+
+static int audio_set_alt(struct usb_function *f, unsigned intf, unsigned alt)
+{
+	struct audio_dev *audio = func_to_audio(f);
+	struct usb_composite_dev *cdev = f->config->cdev;
+
+	pr_debug("audio_set_alt intf %d, alt %d\n", intf, alt);
+	config_ep_by_speed(cdev->gadget, f, audio->in_ep);
+	usb_ep_enable(audio->in_ep);
+	return 0;
+}
+
+static void audio_disable(struct usb_function *f)
+{
+	struct audio_dev	*audio = func_to_audio(f);
+
+	pr_debug("audio_disable\n");
+	usb_ep_disable(audio->in_ep);
+}
+
+/*-------------------------------------------------------------------------*/
+
+static void audio_build_desc(struct audio_dev *audio)
+{
+	u8 *sam_freq;
+	int rate;
+
+	/* Set channel numbers */
+	input_terminal_desc.bNrChannels = 2;
+	as_type_i_desc.bNrChannels = 2;
+
+	/* Set sample rates */
+	rate = SAMPLE_RATE;
+	sam_freq = as_type_i_desc.tSamFreq[0];
+	memcpy(sam_freq, &rate, 3);
+}
+
+/* audio function driver setup/binding */
+static int
+audio_bind(struct usb_configuration *c, struct usb_function *f)
+{
+	struct usb_composite_dev *cdev = c->cdev;
+	struct audio_dev *audio = func_to_audio(f);
+	int status;
+	struct usb_ep *ep;
+	struct usb_request *req;
+	int i;
+
+	audio_build_desc(audio);
+
+	/* allocate instance-specific interface IDs, and patch descriptors */
+	status = usb_interface_id(c, f);
+	if (status < 0)
+		goto fail;
+	ac_interface_desc.bInterfaceNumber = status;
+
+	status = usb_interface_id(c, f);
+	if (status < 0)
+		goto fail;
+	as_interface_alt_0_desc.bInterfaceNumber = status;
+	as_interface_alt_1_desc.bInterfaceNumber = status;
+
+	status = -ENODEV;
+
+	/* allocate our endpoint */
+	ep = usb_ep_autoconfig(cdev->gadget, &fs_as_in_ep_desc);
+	if (!ep)
+		goto fail;
+	audio->in_ep = ep;
+	ep->driver_data = audio; /* claim */
+
+	if (gadget_is_dualspeed(c->cdev->gadget))
+		hs_as_in_ep_desc.bEndpointAddress =
+			fs_as_in_ep_desc.bEndpointAddress;
+
+	f->descriptors = fs_audio_desc;
+	f->hs_descriptors = hs_audio_desc;
+
+	for (i = 0, status = 0; i < IN_EP_REQ_COUNT && status == 0; i++) {
+		req = audio_request_new(ep, IN_EP_MAX_PACKET_SIZE);
+		if (req) {
+			req->context = audio;
+			req->complete = audio_data_complete;
+			audio_req_put(audio, req);
+		} else
+			status = -ENOMEM;
+	}
+
+fail:
+	return status;
+}
+
+static void
+audio_unbind(struct usb_configuration *c, struct usb_function *f)
+{
+	struct audio_dev *audio = func_to_audio(f);
+	struct usb_request *req;
+
+	while ((req = audio_req_get(audio)))
+		audio_request_free(req, audio->in_ep);
+
+	snd_card_free_when_closed(audio->card);
+	kfree(audio);
+}
+
+static void audio_pcm_playback_start(struct audio_dev *audio)
+{
+	audio->start_time = ktime_get();
+	audio->frames_sent = 0;
+	audio_send(audio);
+}
+
+static void audio_pcm_playback_stop(struct audio_dev *audio)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&audio->lock, flags);
+	audio->buffer_start = 0;
+	audio->buffer_end = 0;
+	audio->buffer_pos = 0;
+	spin_unlock_irqrestore(&audio->lock, flags);
+}
+
+static int audio_pcm_open(struct snd_pcm_substream *substream)
+{
+	struct snd_pcm_runtime *runtime = substream->runtime;
+	struct audio_dev *audio = substream->private_data;
+
+	runtime->private_data = audio;
+	runtime->hw = audio_hw_info;
+	snd_pcm_limit_hw_rates(runtime);
+	runtime->hw.channels_max = 2;
+
+	audio->substream = substream;
+	return 0;
+}
+
+static int audio_pcm_close(struct snd_pcm_substream *substream)
+{
+	struct audio_dev *audio = substream->private_data;
+	unsigned long flags;
+
+	spin_lock_irqsave(&audio->lock, flags);
+	audio->substream = NULL;
+	spin_unlock_irqrestore(&audio->lock, flags);
+
+	return 0;
+}
+
+static int audio_pcm_hw_params(struct snd_pcm_substream *substream,
+				struct snd_pcm_hw_params *params)
+{
+	unsigned int channels = params_channels(params);
+	unsigned int rate = params_rate(params);
+
+	if (rate != SAMPLE_RATE)
+		return -EINVAL;
+	if (channels != 2)
+		return -EINVAL;
+
+	return snd_pcm_lib_alloc_vmalloc_buffer(substream,
+		params_buffer_bytes(params));
+}
+
+static int audio_pcm_hw_free(struct snd_pcm_substream *substream)
+{
+	return snd_pcm_lib_free_vmalloc_buffer(substream);
+}
+
+static int audio_pcm_prepare(struct snd_pcm_substream *substream)
+{
+	struct snd_pcm_runtime *runtime = substream->runtime;
+	struct audio_dev *audio = runtime->private_data;
+
+	audio->period = snd_pcm_lib_period_bytes(substream);
+	audio->period_offset = 0;
+	audio->buffer_start = runtime->dma_area;
+	audio->buffer_end = audio->buffer_start
+		+ snd_pcm_lib_buffer_bytes(substream);
+	audio->buffer_pos = audio->buffer_start;
+
+	return 0;
+}
+
+static snd_pcm_uframes_t audio_pcm_pointer(struct snd_pcm_substream *substream)
+{
+	struct snd_pcm_runtime *runtime = substream->runtime;
+	struct audio_dev *audio = runtime->private_data;
+	ssize_t bytes = audio->buffer_pos - audio->buffer_start;
+
+	/* return offset of next frame to fill in our buffer */
+	return bytes_to_frames(runtime, bytes);
+}
+
+static int audio_pcm_playback_trigger(struct snd_pcm_substream *substream,
+					int cmd)
+{
+	struct audio_dev *audio = substream->runtime->private_data;
+	int ret = 0;
+
+	switch (cmd) {
+	case SNDRV_PCM_TRIGGER_START:
+	case SNDRV_PCM_TRIGGER_RESUME:
+		audio_pcm_playback_start(audio);
+		break;
+
+	case SNDRV_PCM_TRIGGER_STOP:
+	case SNDRV_PCM_TRIGGER_SUSPEND:
+		audio_pcm_playback_stop(audio);
+		break;
+
+	default:
+		ret = -EINVAL;
+	}
+
+	return ret;
+}
+
+static struct snd_pcm_ops audio_playback_ops = {
+	.open		= audio_pcm_open,
+	.close		= audio_pcm_close,
+	.ioctl		= snd_pcm_lib_ioctl,
+	.hw_params	= audio_pcm_hw_params,
+	.hw_free	= audio_pcm_hw_free,
+	.prepare	= audio_pcm_prepare,
+	.trigger	= audio_pcm_playback_trigger,
+	.pointer	= audio_pcm_pointer,
+};
+
+int audio_source_bind_config(struct usb_configuration *c,
+		struct audio_source_config *config)
+{
+	struct audio_dev *audio;
+	struct snd_card *card;
+	struct snd_pcm *pcm;
+	int err;
+
+	config->card = -1;
+	config->device = -1;
+
+	audio = kzalloc(sizeof *audio, GFP_KERNEL);
+	if (!audio)
+		return -ENOMEM;
+
+	audio->func.name = "audio_source";
+
+	spin_lock_init(&audio->lock);
+
+	audio->func.bind = audio_bind;
+	audio->func.unbind = audio_unbind;
+	audio->func.set_alt = audio_set_alt;
+	audio->func.setup = audio_setup;
+	audio->func.disable = audio_disable;
+	audio->in_desc = &fs_as_in_ep_desc;
+
+	INIT_LIST_HEAD(&audio->idle_reqs);
+
+	err = snd_card_create(SNDRV_DEFAULT_IDX1, SNDRV_DEFAULT_STR1,
+			THIS_MODULE, 0, &card);
+	if (err)
+		goto snd_card_fail;
+
+	snd_card_set_dev(card, &c->cdev->gadget->dev);
+
+	err = snd_pcm_new(card, "USB audio source", 0, 1, 0, &pcm);
+	if (err)
+		goto pcm_fail;
+	pcm->private_data = audio;
+	pcm->info_flags = 0;
+	audio->pcm = pcm;
+
+	strlcpy(pcm->name, "USB gadget audio", sizeof(pcm->name));
+
+	snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_PLAYBACK, &audio_playback_ops);
+	snd_pcm_lib_preallocate_pages_for_all(pcm, SNDRV_DMA_TYPE_DEV,
+				NULL, 0, 64 * 1024);
+
+	strlcpy(card->driver, "audio_source", sizeof(card->driver));
+	strlcpy(card->shortname, card->driver, sizeof(card->shortname));
+	strlcpy(card->longname, "USB accessory audio source",
+		sizeof(card->longname));
+
+	err = snd_card_register(card);
+	if (err)
+		goto register_fail;
+
+	err = usb_add_function(c, &audio->func);
+	if (err)
+		goto add_fail;
+
+	config->card = pcm->card->number;
+	config->device = pcm->device;
+	audio->card = card;
+	return 0;
+
+add_fail:
+register_fail:
+pcm_fail:
+	snd_card_free(audio->card);
+snd_card_fail:
+	kfree(audio);
+	return err;
+}
diff --git a/drivers/usb/gadget/tegra_udc.c b/drivers/usb/gadget/tegra_udc.c
index aad99a6cd66e..ddf9c602dc89 100644
--- a/drivers/usb/gadget/tegra_udc.c
+++ b/drivers/usb/gadget/tegra_udc.c
@@ -129,8 +129,9 @@ static void done(struct tegra_ep *ep, struct tegra_req *req, int status)
 {
 	struct tegra_udc *udc = NULL;
 	unsigned char stopped = ep->stopped;
-	struct ep_td_struct *curr_td, *next_td;
+	struct ep_td_struct *curr_td, *next_td = 0;
 	int j;
+	int count;
 	BUG_ON(!(in_irq() || irqs_disabled()));
 	udc = (struct tegra_udc *)ep->udc;
 	/* Removed the req from tegra_ep->queue */
@@ -143,12 +144,19 @@ static void done(struct tegra_ep *ep, struct tegra_req *req, int status)
 		status = req->req.status;
 
 	/* Free dtd for the request */
-	next_td = req->head;
-	for (j = 0; j < req->dtd_count; j++) {
+	count = 0;
+	if (ep->last_td) {
+		next_td = ep->last_td;
+		count = ep->last_dtd_count;
+	}
+	ep->last_td = req->head;
+	ep->last_dtd_count = req->dtd_count;
+
+	for (j = 0; j < count; j++) {
 		curr_td = next_td;
-		if (j != req->dtd_count - 1)
+		if (j != count - 1) {
 			next_td = curr_td->next_td_virt;
-
+		}
 		dma_pool_free(udc->td_pool, curr_td, curr_td->td_dma);
 	}
 
@@ -568,6 +576,8 @@ static int tegra_ep_enable(struct usb_ep *_ep,
 	ep->ep.maxpacket = max;
 	ep->desc = desc;
 	ep->stopped = 0;
+	ep->last_td = 0;
+	ep->last_dtd_count = 0;
 
 	/* Controller related setup
 	 * Init EPx Queue Head (Ep Capabilites field in QH
@@ -610,6 +620,8 @@ static int tegra_ep_disable(struct usb_ep *_ep)
 	unsigned long flags = 0;
 	u32 epctrl;
 	int ep_num;
+	struct ep_td_struct *curr_td, *next_td;
+	int j;
 
 	ep = container_of(_ep, struct tegra_ep, ep);
 	if (!_ep || !ep->desc) {
@@ -638,6 +650,18 @@ static int tegra_ep_disable(struct usb_ep *_ep)
 
 	ep->desc = NULL;
 	ep->stopped = 1;
+	if (ep->last_td) {
+		next_td = ep->last_td;
+		for (j = 0; j < ep->last_dtd_count; j++) {
+			curr_td = next_td;
+			dma_pool_free(udc->td_pool, curr_td, curr_td->td_dma);
+			if (j != ep->last_dtd_count - 1) {
+				next_td = curr_td->next_td_virt;
+			}
+		}
+	}
+	ep->last_td =0;
+	ep->last_dtd_count = 0;
 	spin_unlock_irqrestore(&udc->lock, flags);
 
 	VDBG("disabled %s OK", _ep->name);
@@ -1216,6 +1240,76 @@ static int tegra_set_selfpowered(struct usb_gadget *gadget, int is_on)
 	return 0;
 }
 
+static int tegra_usb_set_charging_current(struct tegra_udc *udc)
+{
+	int max_ua;
+
+	if (NULL == udc->vbus_reg)
+		return 0;
+
+	switch (udc->connect_type) {
+	case CONNECT_TYPE_NONE:
+		pr_debug("detected USB charging is disabled");
+		max_ua = 0;
+		break;
+	case CONNECT_TYPE_SDP:
+		pr_debug("detected SDP port");
+		max_ua = USB_CHARGING_SDP_CURRENT_LIMIT_UA;
+		break;
+	case CONNECT_TYPE_DCP:
+		pr_debug("detected DCP port(wall charger)");
+		max_ua = USB_CHARGING_DCP_CURRENT_LIMIT_UA;
+		break;
+	case CONNECT_TYPE_CDP:
+		pr_debug("detected CDP port(1A USB port)");
+		max_ua = USB_CHARGING_CDP_CURRENT_LIMIT_UA;
+		break;
+	case CONNECT_TYPE_NON_STANDARD_CHARGER:
+		pr_debug("detected non-standard charging port");
+		max_ua = USB_CHARGING_NON_STANDARD_CHARGER_CURRENT_LIMIT_UA;
+		break;
+	default:
+		pr_debug("detected USB charging type is unknown");
+		max_ua = 0;
+	}
+
+	return regulator_set_current_limit(udc->vbus_reg, 0, max_ua);
+}
+
+static void tegra_detect_charging_type_is_cdp_or_dcp(struct tegra_udc *udc)
+{
+	u32 portsc;
+	u32 temp;
+	unsigned long flags;
+
+	/* use spinlock to prevent kernel preemption here */
+	spin_lock_irqsave(&udc->lock, flags);
+
+	/* set controller to run which cause D+ pull high */
+	temp = udc_readl(udc, USB_CMD_REG_OFFSET);
+	temp |= USB_CMD_RUN_STOP;
+	udc_writel(udc, temp, USB_CMD_REG_OFFSET);
+
+	udelay(10);
+
+	/* use D+ and D- status to check it is CDP or DCP */
+	portsc = udc_readl(udc, PORTSCX_REG_OFFSET) & PORTSCX_LINE_STATUS_BITS;
+	if (portsc == (PORTSCX_LINE_STATUS_DP_BIT | PORTSCX_LINE_STATUS_DM_BIT))
+		udc->connect_type = CONNECT_TYPE_DCP;
+	else if (portsc == PORTSCX_LINE_STATUS_DP_BIT)
+		udc->connect_type = CONNECT_TYPE_CDP;
+	else
+		/*
+		 * If it take more 100mS between D+ pull high and read Line
+		 * Status, host might initiate the RESET, then we see both
+		 * line status as 0 (SE0). This really should not happen as we
+		 * disabled the kernel preemption before reaching here.
+		 */
+		BUG();
+
+	spin_unlock_irqrestore(&udc->lock, flags);
+}
+
 /**
  * Notify controller that VBUS is powered, called by whatever
  * detects VBUS sessions
@@ -1238,13 +1332,10 @@ static int tegra_vbus_session(struct usb_gadget *gadget, int is_active)
 		dr_controller_reset(udc);
 		udc->vbus_active = 0;
 		udc->usb_state = USB_STATE_DEFAULT;
+		udc->connect_type = CONNECT_TYPE_NONE;
 		spin_unlock_irqrestore(&udc->lock,flags);
 		tegra_usb_phy_power_off(udc->phy);
-		if (udc->vbus_reg) {
-			/* set the current limit to 0mA */
-			regulator_set_current_limit(
-				udc->vbus_reg, 0, 0);
-		}
+		tegra_usb_set_charging_current(udc);
 	} else if (!udc->vbus_active && is_active) {
 		tegra_usb_phy_power_on(udc->phy);
 		/* setup the controller in the device mode */
@@ -1256,18 +1347,23 @@ static int tegra_vbus_session(struct usb_gadget *gadget, int is_active)
 		udc->ep0_state = WAIT_FOR_SETUP;
 		udc->ep0_dir = 0;
 		udc->vbus_active = 1;
+		if (tegra_usb_phy_charger_detected(udc->phy)) {
+			tegra_detect_charging_type_is_cdp_or_dcp(udc);
+		} else {
+			udc->connect_type = CONNECT_TYPE_SDP;
+			/*
+			 * Schedule work to wait for 1000 msec and check for
+			 * a non-standard charger if setup packet is not
+			 * received.
+			 */
+			schedule_delayed_work(&udc->work, msecs_to_jiffies(
+					USB_CHARGER_DETECTION_WAIT_TIME_MS));
+		}
 		/* start the controller */
 		dr_controller_run(udc);
-		if (udc->vbus_reg) {
-			/* set the current limit to 100mA */
-			regulator_set_current_limit(
-				udc->vbus_reg, 0, 100);
-		}
-		/* Schedule work to wait for 1000 msec and check for
-		 * charger if setup packet is not received */
-		schedule_delayed_work(&udc->work,
-			USB_CHARGER_DETECTION_WAIT_TIME_MS);
+		tegra_usb_set_charging_current(udc);
 	}
+
 	return 0;
 }
 
@@ -2095,26 +2191,18 @@ static void tegra_udc_irq_work(struct work_struct *irq_work)
 	DBG("%s(%d) END\n", __func__, __LINE__);
 }
 
-/**
- * If VBUS is detected and setup packet is not received in 100ms then
- * work thread starts and checks for the USB charger detection.
+/*
+ * When VBUS is detected we already know it is DCP/SDP/CDP devices if it is a
+ * standard device; If we did not receive EP0 setup packet, we can assuming it
+ * is a charger capable of 1.8A charging.
  */
 static void tegra_udc_charger_detect_work(struct work_struct *work)
 {
 	struct tegra_udc *udc = container_of(work, struct tegra_udc, work.work);
 	DBG("%s(%d) BEGIN\n", __func__, __LINE__);
 
-	/* check for the platform charger detection */
-	if (tegra_usb_phy_charger_detected(udc->phy)) {
-		printk(KERN_INFO "USB compliant charger detected\n");
-		/* check udc regulator is available for drawing vbus current*/
-		if (udc->vbus_reg) {
-			/* set the current limit in uA */
-			regulator_set_current_limit(
-				udc->vbus_reg, 0,
-				USB_CHARGING_CURRENT_LIMIT_MA*1000);
-		}
-	}
+	udc->connect_type = CONNECT_TYPE_NON_STANDARD_CHARGER;
+	tegra_usb_set_charging_current(udc);
 
 	DBG("%s(%d) END\n", __func__, __LINE__);
 }
@@ -2159,10 +2247,8 @@ static irqreturn_t tegra_udc_irq(int irq, void *_udc)
 	}
 
 	/* Disable ISR for OTG host mode */
-	if (udc->stopped) {
-		spin_unlock_irqrestore(&udc->lock, flags);
-		return status;
-	}
+	if (udc->stopped)
+		goto done;
 
 	/* Fence read for coherency of AHB master intiated writes */
 	readb(IO_ADDRESS(IO_PPCS_PHYS + USB1_PREFETCH_ID));
@@ -2170,6 +2256,9 @@ static irqreturn_t tegra_udc_irq(int irq, void *_udc)
 	irq_src = udc_readl(udc, USB_STS_REG_OFFSET) &
 				udc_readl(udc, USB_INTR_REG_OFFSET);
 
+	if (irq_src == 0)
+		goto done;
+
 	/* Clear notification bits */
 	udc_writel(udc, irq_src, USB_STS_REG_OFFSET);
 
@@ -2226,6 +2315,7 @@ static irqreturn_t tegra_udc_irq(int irq, void *_udc)
 	if (irq_src & (USB_STS_ERR | USB_STS_SYS_ERR))
 		VDBG("Error IRQ %x", irq_src);
 
+done:
 	spin_unlock_irqrestore(&udc->lock, flags);
 	return status;
 }
@@ -2274,11 +2364,13 @@ static int tegra_udc_start(struct usb_gadget_driver *driver,
 
 
 	/* Enable DR IRQ reg and Set usbcmd reg  Run bit */
-	dr_controller_run(udc);
-	udc->usb_state = USB_STATE_ATTACHED;
-	udc->ep0_state = WAIT_FOR_SETUP;
-	udc->ep0_dir = 0;
-	udc->vbus_active = vbus_enabled(udc);
+	if (vbus_enabled(udc)) {
+		dr_controller_run(udc);
+		udc->usb_state = USB_STATE_ATTACHED;
+		udc->ep0_state = WAIT_FOR_SETUP;
+		udc->ep0_dir = 0;
+		udc->vbus_active = vbus_enabled(udc);
+	}
 
 	printk(KERN_INFO "%s: bind to driver %s\n",
 			udc->gadget.name, driver->driver.name);
@@ -2632,7 +2724,7 @@ static int __init tegra_udc_probe(struct platform_device *pdev)
 	}
 #else
 	/* Power down the phy if cable is not connected */
-	if (!vbus_enabled())
+	if (!vbus_enabled(udc))
 		tegra_usb_phy_power_off(udc->phy);
 #endif
 
diff --git a/drivers/usb/gadget/tegra_udc.h b/drivers/usb/gadget/tegra_udc.h
index e94543fd98e3..094e3eb0e458 100644
--- a/drivers/usb/gadget/tegra_udc.h
+++ b/drivers/usb/gadget/tegra_udc.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2011 NVIDIA Corporation
+ * Copyright (c) 2012, NVIDIA CORPORATION.  All rights reserved.
  *
  * Description:
  * High-speed USB device controller driver.
@@ -38,7 +38,11 @@
 #define USB_MAX_CTRL_PAYLOAD		64
 
  /* Charger current limit=1800mA, as per the USB charger spec */
-#define USB_CHARGING_CURRENT_LIMIT_MA 1800
+#define USB_CHARGING_DCP_CURRENT_LIMIT_UA 1800000
+#define USB_CHARGING_CDP_CURRENT_LIMIT_UA 900000
+#define USB_CHARGING_SDP_CURRENT_LIMIT_UA 100000
+#define USB_CHARGING_NON_STANDARD_CHARGER_CURRENT_LIMIT_UA 1800000
+
  /* 1 sec wait time for charger detection after vbus is detected */
 #define USB_CHARGER_DETECTION_WAIT_TIME_MS 1000
 #define BOOST_TRIGGER_SIZE 4096
@@ -156,6 +160,8 @@
 #define  PORTSCX_PORT_SUSPEND                 0x00000080
 #define  PORTSCX_PORT_RESET                   0x00000100
 #define  PORTSCX_LINE_STATUS_BITS             0x00000C00
+#define  PORTSCX_LINE_STATUS_DP_BIT           0x00000800
+#define  PORTSCX_LINE_STATUS_DM_BIT           0x00000400
 #define  PORTSCX_PORT_POWER                   0x00001000
 #define  PORTSCX_PORT_INDICTOR_CTRL           0x0000C000
 #define  PORTSCX_PORT_TEST_CTRL               0x000F0000
@@ -390,11 +396,21 @@ struct tegra_ep {
 	struct ep_queue_head *qh;
 	const struct usb_endpoint_descriptor *desc;
 	struct usb_gadget *gadget;
+	struct ep_td_struct *last_td;
+	int last_dtd_count;
 
 	char name[14];
 	unsigned stopped:1;
 };
 
+enum tegra_connect_type {
+	CONNECT_TYPE_NONE,
+	CONNECT_TYPE_SDP,
+	CONNECT_TYPE_DCP,
+	CONNECT_TYPE_CDP,
+	CONNECT_TYPE_NON_STANDARD_CHARGER
+};
+
 struct tegra_udc {
 	struct usb_gadget gadget;
 	struct usb_gadget_driver *driver;
@@ -415,6 +431,7 @@ struct tegra_udc {
 	struct work_struct boost_cpufreq_work;
 	/* irq work for controlling the usb power */
 	struct work_struct irq_work;
+	enum tegra_connect_type connect_type;
 	void __iomem *regs;
 	size_t ep_qh_size;		/* size after alignment adjustment*/
 	dma_addr_t ep_qh_dma;		/* dma address of QH */