From f6cee36f897dac2264b4bbee042117861c3391c5 Mon Sep 17 00:00:00 2001
From: Mike Lockwood <lockwood@android.com>
Date: Wed, 9 Feb 2011 09:38:26 -0500
Subject: [PATCH] USB: gadget: android: Support switching vendor ID when
 configuration changes

Based on the list of enabled USB functions, we can now switch the vendor ID
as well as the product ID.

Signed-off-by: Mike Lockwood <lockwood@android.com>
---
 drivers/usb/gadget/android.c          | 32 +++++++++++++++++++++++++-------
 include/linux/usb/android_composite.h |  7 ++++++-
 2 files changed, 31 insertions(+), 8 deletions(-)

diff --git a/drivers/usb/gadget/android.c b/drivers/usb/gadget/android.c
index 3d3fc79..e49ef2c 100644
--- a/drivers/usb/gadget/android.c
+++ b/drivers/usb/gadget/android.c
@@ -65,6 +65,7 @@ struct android_dev {
 	int num_functions;
 	char **functions;
 
+	int vendor_id;
 	int product_id;
 	int version;
 };
@@ -254,6 +255,22 @@ static int product_matches_functions(struct android_usb_product *p)
 	return 1;
 }
 
+static int get_vendor_id(struct android_dev *dev)
+{
+	struct android_usb_product *p = dev->products;
+	int count = dev->num_products;
+	int i;
+
+	if (p) {
+		for (i = 0; i < count; i++, p++) {
+			if (p->vendor_id && product_matches_functions(p))
+				return p->vendor_id;
+		}
+	}
+	/* use default vendor ID */
+	return dev->vendor_id;
+}
+
 static int get_product_id(struct android_dev *dev)
 {
 	struct android_usb_product *p = dev->products;
@@ -274,7 +291,7 @@ static int android_bind(struct usb_composite_dev *cdev)
 {
 	struct android_dev *dev = _android_dev;
 	struct usb_gadget	*gadget = cdev->gadget;
-	int			gcnum, id, product_id, ret;
+	int			gcnum, id, ret;
 
 	printk(KERN_INFO "android_bind\n");
 
@@ -324,8 +341,8 @@ static int android_bind(struct usb_composite_dev *cdev)
 
 	usb_gadget_set_selfpowered(gadget);
 	dev->cdev = cdev;
-	product_id = get_product_id(dev);
-	device_desc.idProduct = __constant_cpu_to_le16(product_id);
+	device_desc.idVendor = __constant_cpu_to_le16(get_vendor_id(dev));
+	device_desc.idProduct = __constant_cpu_to_le16(get_product_id(dev));
 	cdev->desc.idProduct = device_desc.idProduct;
 
 	return 0;
@@ -394,7 +411,6 @@ void android_enable_function(struct usb_function *f, int enable)
 {
 	struct android_dev *dev = _android_dev;
 	int disable = !enable;
-	int product_id;
 
 	if (!!f->disabled != disable) {
 		usb_function_set_enabled(f, !disable);
@@ -416,8 +432,8 @@ void android_enable_function(struct usb_function *f, int enable)
 
 		update_dev_desc(dev);
 
-		product_id = get_product_id(dev);
-		device_desc.idProduct = __constant_cpu_to_le16(product_id);
+		device_desc.idVendor = __constant_cpu_to_le16(get_vendor_id(dev));
+		device_desc.idProduct = __constant_cpu_to_le16(get_product_id(dev));
 		if (dev->cdev)
 			dev->cdev->desc.idProduct = device_desc.idProduct;
 		usb_composite_force_reset(dev->cdev);
@@ -436,9 +452,11 @@ static int android_probe(struct platform_device *pdev)
 		dev->num_products = pdata->num_products;
 		dev->functions = pdata->functions;
 		dev->num_functions = pdata->num_functions;
-		if (pdata->vendor_id)
+		if (pdata->vendor_id) {
+			dev->vendor_id = pdata->vendor_id;
 			device_desc.idVendor =
 				__constant_cpu_to_le16(pdata->vendor_id);
+		}
 		if (pdata->product_id) {
 			dev->product_id = pdata->product_id;
 			device_desc.idProduct =
diff --git a/include/linux/usb/android_composite.h b/include/linux/usb/android_composite.h
index 62e72e3..7f90007 100644
--- a/include/linux/usb/android_composite.h
+++ b/include/linux/usb/android_composite.h
@@ -27,7 +27,12 @@ struct android_usb_function {
 };
 
 struct android_usb_product {
-	/* Default product ID. */
+	/* Vendor ID for this set of functions.
+	 * Default vendor_id in platform data will be used if this is zero.
+	 */
+	__u16 vendor_id;
+
+	/* Product ID for this set of functions. */
 	__u16 product_id;
 
 	/* List of function names associated with this product.
-- 
2.7.4