USB: serial: add support for multi-interface functions

index 27e3bb58c872..2a38810a3979 100644
@@ -1114,8 +1114,6 @@ int usb_serial_suspend(struct usb_interface *intf, pm_message_t message)
 	struct usb_serial *serial = usb_get_intfdata(intf);
 	int i, r = 0;
 
-	serial->suspending = 1;
-
 	/*
 	 * serial->type->suspend() MUST return 0 in system sleep context,
 	 * otherwise, the resume callback has to recover device from

@@ -1123,10 +1121,8 @@ int usb_serial_suspend(struct usb_interface *intf, pm_message_t message)
 	 */
 	if (serial->type->suspend) {
 		r = serial->type->suspend(serial, message);
-		if (r < 0) {
-			serial->suspending = 0;
+		if (r < 0)
 			goto err_out;
-		}
 	}
 
 	for (i = 0; i < serial->num_ports; ++i)

@@ -1151,7 +1147,6 @@ int usb_serial_resume(struct usb_interface *intf)
 
 	usb_serial_unpoison_port_urbs(serial);
 
-	serial->suspending = 0;
 	if (serial->type->resume)
 		rv = serial->type->resume(serial);
 	else

@@ -1168,7 +1163,6 @@ static int usb_serial_reset_resume(struct usb_interface *intf)
 
 	usb_serial_unpoison_port_urbs(serial);
 
-	serial->suspending = 0;
 	if (serial->type->reset_resume) {
 		rv = serial->type->reset_resume(serial);
 	} else {

index 952272002e48..7efba6caaadc 100644
@@ -146,7 +146,6 @@ struct usb_serial {
 	struct usb_serial_driver	*type;
 	struct usb_interface		*interface;
 	unsigned char			disconnected:1;
-	unsigned char			suspending:1;
 	unsigned char			attached:1;
 	unsigned char			minors_reserved:1;
 	unsigned char			num_ports;

index 2a38810a3979..d981809c4ed3 100644
@@ -711,36 +711,47 @@ static const struct tty_port_operations serial_port_ops = {
 	.shutdown		= serial_port_shutdown,
 };
 
+static void store_endpoint(struct usb_serial *serial,
+					struct usb_serial_endpoints *epds,
+					struct usb_endpoint_descriptor *epd)
+{
+	struct device *dev = &serial->interface->dev;
+	u8 addr = epd->bEndpointAddress;
+
+	if (usb_endpoint_is_bulk_in(epd)) {
+		if (epds->num_bulk_in == ARRAY_SIZE(epds->bulk_in))
+			return;
+		dev_dbg(dev, "found bulk in endpoint %02x\n", addr);
+		epds->bulk_in[epds->num_bulk_in++] = epd;
+	} else if (usb_endpoint_is_bulk_out(epd)) {
+		if (epds->num_bulk_out == ARRAY_SIZE(epds->bulk_out))
+			return;
+		dev_dbg(dev, "found bulk out endpoint %02x\n", addr);
+		epds->bulk_out[epds->num_bulk_out++] = epd;
+	} else if (usb_endpoint_is_int_in(epd)) {
+		if (epds->num_interrupt_in == ARRAY_SIZE(epds->interrupt_in))
+			return;
+		dev_dbg(dev, "found interrupt in endpoint %02x\n", addr);
+		epds->interrupt_in[epds->num_interrupt_in++] = epd;
+	} else if (usb_endpoint_is_int_out(epd)) {
+		if (epds->num_interrupt_out == ARRAY_SIZE(epds->interrupt_out))
+			return;
+		dev_dbg(dev, "found interrupt out endpoint %02x\n", addr);
+		epds->interrupt_out[epds->num_interrupt_out++] = epd;
+	}
+}
+
 static void find_endpoints(struct usb_serial *serial,
 					struct usb_serial_endpoints *epds)
 {
-	struct device *dev = &serial->interface->dev;
 	struct usb_host_interface *iface_desc;
 	struct usb_endpoint_descriptor *epd;
 	unsigned int i;
 
-	BUILD_BUG_ON(ARRAY_SIZE(epds->bulk_in) < USB_MAXENDPOINTS / 2);
-	BUILD_BUG_ON(ARRAY_SIZE(epds->bulk_out) < USB_MAXENDPOINTS / 2);
-	BUILD_BUG_ON(ARRAY_SIZE(epds->interrupt_in) < USB_MAXENDPOINTS / 2);
-	BUILD_BUG_ON(ARRAY_SIZE(epds->interrupt_out) < USB_MAXENDPOINTS / 2);
-
 	iface_desc = serial->interface->cur_altsetting;
 	for (i = 0; i < iface_desc->desc.bNumEndpoints; ++i) {
 		epd = &iface_desc->endpoint[i].desc;
-
-		if (usb_endpoint_is_bulk_in(epd)) {
-			dev_dbg(dev, "found bulk in on endpoint %u\n", i);
-			epds->bulk_in[epds->num_bulk_in++] = epd;
-		} else if (usb_endpoint_is_bulk_out(epd)) {
-			dev_dbg(dev, "found bulk out on endpoint %u\n", i);
-			epds->bulk_out[epds->num_bulk_out++] = epd;
-		} else if (usb_endpoint_is_int_in(epd)) {
-			dev_dbg(dev, "found interrupt in on endpoint %u\n", i);
-			epds->interrupt_in[epds->num_interrupt_in++] = epd;
-		} else if (usb_endpoint_is_int_out(epd)) {
-			dev_dbg(dev, "found interrupt out on endpoint %u\n", i);
-			epds->interrupt_out[epds->num_interrupt_out++] = epd;
-		}
+		store_endpoint(serial, epds, epd);
 	}
 }
 

index d981809c4ed3..aaae71a0bbff 100644
@@ -121,6 +121,44 @@ static void release_minors(struct usb_serial *serial)
 	serial->minors_reserved = 0;
 }
 
+int usb_serial_claim_interface(struct usb_serial *serial, struct usb_interface *intf)
+{
+	struct usb_driver *driver = serial->type->usb_driver;
+	int ret;
+
+	if (serial->sibling)
+		return -EBUSY;
+
+	ret = usb_driver_claim_interface(driver, intf, serial);
+	if (ret) {
+		dev_err(&serial->interface->dev,
+				"failed to claim sibling interface: %d\n", ret);
+		return ret;
+	}
+
+	serial->sibling = intf;
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(usb_serial_claim_interface);
+
+static void release_sibling(struct usb_serial *serial, struct usb_interface *intf)
+{
+	struct usb_driver *driver = serial->type->usb_driver;
+	struct usb_interface *sibling;
+
+	if (!serial->sibling)
+		return;
+
+	if (intf == serial->sibling)
+		sibling = serial->interface;
+	else
+		sibling = serial->sibling;
+
+	usb_set_intfdata(sibling, NULL);
+	usb_driver_release_interface(driver, sibling);
+}
+
 static void destroy_serial(struct kref *kref)
 {
 	struct usb_serial *serial;

@@ -742,13 +780,14 @@ static void store_endpoint(struct usb_serial *serial,
 }
 
 static void find_endpoints(struct usb_serial *serial,
-					struct usb_serial_endpoints *epds)
+					struct usb_serial_endpoints *epds,
+					struct usb_interface *intf)
 {
 	struct usb_host_interface *iface_desc;
 	struct usb_endpoint_descriptor *epd;
 	unsigned int i;
 
-	iface_desc = serial->interface->cur_altsetting;
+	iface_desc = intf->cur_altsetting;
 	for (i = 0; i < iface_desc->desc.bNumEndpoints; ++i) {
 		epd = &iface_desc->endpoint[i].desc;
 		store_endpoint(serial, epds, epd);

@@ -917,7 +956,7 @@ static int usb_serial_probe(struct usb_interface *interface,
 
 		if (retval) {
 			dev_dbg(ddev, "sub driver rejected device\n");
-			goto err_put_serial;
+			goto err_release_sibling;
 		}
 	}
 

@@ -925,10 +964,12 @@ static int usb_serial_probe(struct usb_interface *interface,
 	epds = kzalloc(sizeof(*epds), GFP_KERNEL);
 	if (!epds) {
 		retval = -ENOMEM;
-		goto err_put_serial;
+		goto err_release_sibling;
 	}
 
-	find_endpoints(serial, epds);
+	find_endpoints(serial, epds, interface);
+	if (serial->sibling)
+		find_endpoints(serial, epds, serial->sibling);
 
 	if (epds->num_bulk_in < type->num_bulk_in ||
 			epds->num_bulk_out < type->num_bulk_out ||

@@ -1076,7 +1117,8 @@ static int usb_serial_probe(struct usb_interface *interface,
 
 err_free_epds:
 	kfree(epds);
-err_put_serial:
+err_release_sibling:
+	release_sibling(serial, interface);
 	usb_serial_put(serial);
 err_put_module:
 	module_put(type->driver.owner);

@@ -1092,6 +1134,10 @@ static void usb_serial_disconnect(struct usb_interface *interface)
 	struct usb_serial_port *port;
 	struct tty_struct *tty;
 
+	/* sibling interface is cleaning up */
+	if (!serial)
+		return;
+
 	usb_serial_console_disconnect(serial);
 
 	mutex_lock(&serial->disc_mutex);

@@ -1115,6 +1161,8 @@ static void usb_serial_disconnect(struct usb_interface *interface)
 	if (serial->type->disconnect)
 		serial->type->disconnect(serial);
 
+	release_sibling(serial, interface);
+
 	/* let the last holder of this object cause it to be cleaned up */
 	usb_serial_put(serial);
 	dev_info(dev, "device disconnected\n");

@@ -1123,7 +1171,11 @@ static void usb_serial_disconnect(struct usb_interface *interface)
 int usb_serial_suspend(struct usb_interface *intf, pm_message_t message)
 {
 	struct usb_serial *serial = usb_get_intfdata(intf);
-	int i, r = 0;
+	int i, r;
+
+	/* suspend when called for first sibling interface */
+	if (serial->suspend_count++)
+		return 0;
 
 	/*
 	 * serial->type->suspend() MUST return 0 in system sleep context,

@@ -1132,14 +1184,16 @@ int usb_serial_suspend(struct usb_interface *intf, pm_message_t message)
 	 */
 	if (serial->type->suspend) {
 		r = serial->type->suspend(serial, message);
-		if (r < 0)
-			goto err_out;
+		if (r < 0) {
+			serial->suspend_count--;
+			return r;
+		}
 	}
 
 	for (i = 0; i < serial->num_ports; ++i)
 		usb_serial_port_poison_urbs(serial->port[i]);
-err_out:
-	return r;
+
+	return 0;
 }
 EXPORT_SYMBOL(usb_serial_suspend);
 

@@ -1156,6 +1210,10 @@ int usb_serial_resume(struct usb_interface *intf)
 	struct usb_serial *serial = usb_get_intfdata(intf);
 	int rv;
 
+	/* resume when called for last sibling interface */
+	if (--serial->suspend_count)
+		return 0;
+
 	usb_serial_unpoison_port_urbs(serial);
 
 	if (serial->type->resume)

@@ -1172,6 +1230,10 @@ static int usb_serial_reset_resume(struct usb_interface *intf)
 	struct usb_serial *serial = usb_get_intfdata(intf);
 	int rv;
 
+	/* resume when called for last sibling interface */
+	if (--serial->suspend_count)
+		return 0;
+
 	usb_serial_unpoison_port_urbs(serial);
 
 	if (serial->type->reset_resume) {

index 7efba6caaadc..e9b90577f50b 100644
@@ -130,6 +130,8 @@ static inline void usb_set_serial_port_data(struct usb_serial_port *port,
  * @dev: pointer to the struct usb_device for this device
  * @type: pointer to the struct usb_serial_driver for this device
  * @interface: pointer to the struct usb_interface for this device
+ * @sibling: pointer to the struct usb_interface of any sibling interface
+ * @suspend_count: number of suspended (sibling) interfaces
  * @num_ports: the number of ports this device has
  * @num_interrupt_in: number of interrupt in endpoints we have
  * @num_interrupt_out: number of interrupt out endpoints we have

@@ -145,6 +147,8 @@ struct usb_serial {
 	struct usb_device		*dev;
 	struct usb_serial_driver	*type;
 	struct usb_interface		*interface;
+	struct usb_interface		*sibling;
+	unsigned int			suspend_count;
 	unsigned char			disconnected:1;
 	unsigned char			attached:1;
 	unsigned char			minors_reserved:1;

@@ -334,6 +338,9 @@ static inline void usb_serial_console_disconnect(struct usb_serial *serial) {}
 /* Functions needed by other parts of the usbserial core */
 struct usb_serial_port *usb_serial_port_get_by_minor(unsigned int minor);
 void usb_serial_put(struct usb_serial *serial);
+
+int usb_serial_claim_interface(struct usb_serial *serial, struct usb_interface *intf);
+
 int usb_serial_generic_open(struct tty_struct *tty, struct usb_serial_port *port);
 int usb_serial_generic_write_start(struct usb_serial_port *port, gfp_t mem_flags);
 int usb_serial_generic_write(struct tty_struct *tty, struct usb_serial_port *port,

index c59c8b47a120..88c73f88cb26 100644
@@ -16,6 +16,7 @@
 #include <linux/slab.h>
 #include <linux/tty.h>
 #include <linux/usb.h>
+#include <linux/usb/cdc.h>
 #include <linux/usb/serial.h>
 
 struct xr_txrx_clk_mask {

@@ -550,15 +551,34 @@ static void xr_close(struct usb_serial_port *port)
 
 static int xr_probe(struct usb_serial *serial, const struct usb_device_id *id)
 {
-	/* Don't bind to control interface */
-	if (serial->interface->cur_altsetting->desc.bInterfaceNumber == 0)
+	struct usb_interface *control = serial->interface;
+	struct usb_host_interface *alt = control->cur_altsetting;
+	struct usb_cdc_parsed_header hdrs;
+	struct usb_cdc_union_desc *desc;
+	struct usb_interface *data;
+	int ret;
+
+	ret = cdc_parse_cdc_header(&hdrs, control, alt->extra, alt->extralen);
+	if (ret < 0)
 		return -ENODEV;
 
+	desc = hdrs.usb_cdc_union_desc;
+	if (!desc)
+		return -ENODEV;
+
+	data = usb_ifnum_to_if(serial->dev, desc->bSlaveInterface0);
+	if (!data)
+		return -ENODEV;
+
+	ret = usb_serial_claim_interface(serial, data);
+	if (ret)
+		return ret;
+
 	return 0;
 }
 
 static const struct usb_device_id id_table[] = {
-	{ USB_DEVICE(0x04e2, 0x1410) }, /* XR21V141X */
+	{ USB_DEVICE_INTERFACE_CLASS(0x04e2, 0x1410, USB_CLASS_COMM) }, /* XR21V141X */
 	{ }
 };
 MODULE_DEVICE_TABLE(usb, id_table);