usb: gadget: printer: allocate and init otg descriptor by otg capabilities

Allocate and initialize usb otg descriptor according to gadget otg
capabilities, add it for each usb configurations. If otg capability
is not defined, keep its original otg descriptor unchanged.
Reviewed-by: Roger Quadros <rogerq@ti.com>
Signed-off-by: Li Jun <jun.li@freescale.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>

drivers/usb/gadget/legacy/printer.c

@@ -82,16 +82,7 @@ static struct usb_device_descriptor device_desc = {
 	.bNumConfigurations =	1
 };
 
-static struct usb_otg_descriptor otg_descriptor = {
-	.bLength =              sizeof otg_descriptor,
-	.bDescriptorType =      USB_DT_OTG,
-	.bmAttributes =         USB_OTG_SRP,
-};
-
-static const struct usb_descriptor_header *otg_desc[] = {
-	(struct usb_descriptor_header *) &otg_descriptor,
-	NULL,
-};
+static const struct usb_descriptor_header *otg_desc[2];
 
 /*-------------------------------------------------------------------------*/
 
@@ -136,7 +127,6 @@ static int printer_do_config(struct usb_configuration *c)
 	usb_gadget_set_selfpowered(gadget);
 
 	if (gadget_is_otg(gadget)) {
-		otg_descriptor.bmAttributes |= USB_OTG_HNP;
 		printer_cfg_driver.descriptors = otg_desc;
 		printer_cfg_driver.bmAttributes |= USB_CONFIG_ATT_WAKEUP;
 	}
@@ -174,21 +164,39 @@ static int printer_bind(struct usb_composite_dev *cdev)
 	opts->q_len = QLEN;
 
 	ret = usb_string_ids_tab(cdev, strings);
-	if (ret < 0) {
-		usb_put_function_instance(fi_printer);
-		return ret;
-	}
+	if (ret < 0)
+		goto fail_put_func_inst;
+
 	device_desc.iManufacturer = strings[USB_GADGET_MANUFACTURER_IDX].id;
 	device_desc.iProduct = strings[USB_GADGET_PRODUCT_IDX].id;
 	device_desc.iSerialNumber = strings[USB_GADGET_SERIAL_IDX].id;
 
-	ret = usb_add_config(cdev, &printer_cfg_driver, printer_do_config);
-	if (ret) {
-		usb_put_function_instance(fi_printer);
-		return ret;
+	if (gadget_is_otg(cdev->gadget) && !otg_desc[0]) {
+		struct usb_descriptor_header *usb_desc;
+
+		usb_desc = usb_otg_descriptor_alloc(cdev->gadget);
+		if (!usb_desc) {
+			ret = -ENOMEM;
+			goto fail_put_func_inst;
+		}
+		usb_otg_descriptor_init(cdev->gadget, usb_desc);
+		otg_desc[0] = usb_desc;
+		otg_desc[1] = NULL;
 	}
+
+	ret = usb_add_config(cdev, &printer_cfg_driver, printer_do_config);
+	if (ret)
+		goto fail_free_otg_desc;
+
 	usb_composite_overwrite_options(cdev, &coverwrite);
 	return ret;
+
+fail_free_otg_desc:
+	kfree(otg_desc[0]);
+	otg_desc[0] = NULL;
+fail_put_func_inst:
+	usb_put_function_instance(fi_printer);
+	return ret;
 }
 
 static int printer_unbind(struct usb_composite_dev *cdev)
@@ -196,6 +204,9 @@ static int printer_unbind(struct usb_composite_dev *cdev)
 	usb_put_function(f_printer);
 	usb_put_function_instance(fi_printer);
 
+	kfree(otg_desc[0]);
+	otg_desc[0] = NULL;
+
 	return 0;
 }