USB: serial: refactor port endpoint setup

Make the probe callback more readable by refactoring the port
endpoint-resource setup by adding four helper functions.
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Johan Hovold <johan@kernel.org>

drivers/usb/serial/usb-serial.c

@@ -742,6 +742,124 @@ static void find_endpoints(struct usb_serial *serial,
 	}
 }
 
+static int setup_port_bulk_in(struct usb_serial_port *port,
+					struct usb_endpoint_descriptor *epd)
+{
+	struct usb_serial_driver *type = port->serial->type;
+	struct usb_device *udev = port->serial->dev;
+	int buffer_size;
+	int i;
+
+	buffer_size = max_t(int, type->bulk_in_size, usb_endpoint_maxp(epd));
+	port->bulk_in_size = buffer_size;
+	port->bulk_in_endpointAddress = epd->bEndpointAddress;
+
+	for (i = 0; i < ARRAY_SIZE(port->read_urbs); ++i) {
+		set_bit(i, &port->read_urbs_free);
+		port->read_urbs[i] = usb_alloc_urb(0, GFP_KERNEL);
+		if (!port->read_urbs[i])
+			return -ENOMEM;
+		port->bulk_in_buffers[i] = kmalloc(buffer_size, GFP_KERNEL);
+		if (!port->bulk_in_buffers[i])
+			return -ENOMEM;
+		usb_fill_bulk_urb(port->read_urbs[i], udev,
+				usb_rcvbulkpipe(udev, epd->bEndpointAddress),
+				port->bulk_in_buffers[i], buffer_size,
+				type->read_bulk_callback, port);
+	}
+
+	port->read_urb = port->read_urbs[0];
+	port->bulk_in_buffer = port->bulk_in_buffers[0];
+
+	return 0;
+}
+
+static int setup_port_bulk_out(struct usb_serial_port *port,
+					struct usb_endpoint_descriptor *epd)
+{
+	struct usb_serial_driver *type = port->serial->type;
+	struct usb_device *udev = port->serial->dev;
+	int buffer_size;
+	int i;
+
+	if (kfifo_alloc(&port->write_fifo, PAGE_SIZE, GFP_KERNEL))
+		return -ENOMEM;
+	if (type->bulk_out_size)
+		buffer_size = type->bulk_out_size;
+	else
+		buffer_size = usb_endpoint_maxp(epd);
+	port->bulk_out_size = buffer_size;
+	port->bulk_out_endpointAddress = epd->bEndpointAddress;
+
+	for (i = 0; i < ARRAY_SIZE(port->write_urbs); ++i) {
+		set_bit(i, &port->write_urbs_free);
+		port->write_urbs[i] = usb_alloc_urb(0, GFP_KERNEL);
+		if (!port->write_urbs[i])
+			return -ENOMEM;
+		port->bulk_out_buffers[i] = kmalloc(buffer_size, GFP_KERNEL);
+		if (!port->bulk_out_buffers[i])
+			return -ENOMEM;
+		usb_fill_bulk_urb(port->write_urbs[i], udev,
+				usb_sndbulkpipe(udev, epd->bEndpointAddress),
+				port->bulk_out_buffers[i], buffer_size,
+				type->write_bulk_callback, port);
+	}
+
+	port->write_urb = port->write_urbs[0];
+	port->bulk_out_buffer = port->bulk_out_buffers[0];
+
+	return 0;
+}
+
+static int setup_port_interrupt_in(struct usb_serial_port *port,
+					struct usb_endpoint_descriptor *epd)
+{
+	struct usb_serial_driver *type = port->serial->type;
+	struct usb_device *udev = port->serial->dev;
+	int buffer_size;
+
+	port->interrupt_in_urb = usb_alloc_urb(0, GFP_KERNEL);
+	if (!port->interrupt_in_urb)
+		return -ENOMEM;
+	buffer_size = usb_endpoint_maxp(epd);
+	port->interrupt_in_endpointAddress = epd->bEndpointAddress;
+	port->interrupt_in_buffer = kmalloc(buffer_size, GFP_KERNEL);
+	if (!port->interrupt_in_buffer)
+		return -ENOMEM;
+	usb_fill_int_urb(port->interrupt_in_urb, udev,
+			usb_rcvintpipe(udev, epd->bEndpointAddress),
+			port->interrupt_in_buffer, buffer_size,
+			type->read_int_callback, port,
+			epd->bInterval);
+
+	return 0;
+}
+
+static int setup_port_interrupt_out(struct usb_serial_port *port,
+					struct usb_endpoint_descriptor *epd)
+{
+	struct usb_serial_driver *type = port->serial->type;
+	struct usb_device *udev = port->serial->dev;
+	int buffer_size;
+
+	port->interrupt_out_urb = usb_alloc_urb(0, GFP_KERNEL);
+	if (!port->interrupt_out_urb)
+		return -ENOMEM;
+	buffer_size = usb_endpoint_maxp(epd);
+	port->interrupt_out_size = buffer_size;
+	port->interrupt_out_endpointAddress = epd->bEndpointAddress;
+	port->interrupt_out_buffer = kmalloc(buffer_size, GFP_KERNEL);
+	if (!port->interrupt_out_buffer)
+		return -ENOMEM;
+	usb_fill_int_urb(port->interrupt_out_urb, udev,
+			usb_sndintpipe(udev, epd->bEndpointAddress),
+			port->interrupt_out_buffer, buffer_size,
+			type->write_int_callback, port,
+			epd->bInterval);
+
+	return 0;
+}
+
 static int usb_serial_probe(struct usb_interface *interface,
 			       const struct usb_device_id *id)
 {
@@ -749,13 +867,10 @@ static int usb_serial_probe(struct usb_interface *interface,
 	struct usb_device *dev = interface_to_usbdev(interface);
 	struct usb_serial *serial = NULL;
 	struct usb_serial_port *port;
-	struct usb_endpoint_descriptor *endpoint;
 	struct usb_serial_endpoints *epds;
 	struct usb_serial_driver *type = NULL;
 	int retval;
-	int buffer_size;
 	int i;
-	int j;
 	int num_ports = 0;
 	unsigned char max_endpoints;
 
@@ -867,86 +982,24 @@ static int usb_serial_probe(struct usb_interface *interface,
 
 	/* set up the endpoint information */
 	for (i = 0; i < epds->num_bulk_in; ++i) {
-		endpoint = epds->bulk_in[i];
-		port = serial->port[i];
-		buffer_size = max_t(int, serial->type->bulk_in_size,
-				usb_endpoint_maxp(endpoint));
-		port->bulk_in_size = buffer_size;
-		port->bulk_in_endpointAddress = endpoint->bEndpointAddress;
-
-		for (j = 0; j < ARRAY_SIZE(port->read_urbs); ++j) {
-			set_bit(j, &port->read_urbs_free);
-			port->read_urbs[j] = usb_alloc_urb(0, GFP_KERNEL);
-			if (!port->read_urbs[j])
-				goto probe_error;
-			port->bulk_in_buffers[j] = kmalloc(buffer_size,
-								GFP_KERNEL);
-			if (!port->bulk_in_buffers[j])
-				goto probe_error;
-			usb_fill_bulk_urb(port->read_urbs[j], dev,
-					usb_rcvbulkpipe(dev,
-						endpoint->bEndpointAddress),
-					port->bulk_in_buffers[j], buffer_size,
-					serial->type->read_bulk_callback,
-					port);
-		}
-
-		port->read_urb = port->read_urbs[0];
-		port->bulk_in_buffer = port->bulk_in_buffers[0];
+		retval = setup_port_bulk_in(serial->port[i], epds->bulk_in[i]);
+		if (retval)
+			goto probe_error;
 	}
 
 	for (i = 0; i < epds->num_bulk_out; ++i) {
-		endpoint = epds->bulk_out[i];
-		port = serial->port[i];
-		if (kfifo_alloc(&port->write_fifo, PAGE_SIZE, GFP_KERNEL))
+		retval = setup_port_bulk_out(serial->port[i],
+				epds->bulk_out[i]);
+		if (retval)
 			goto probe_error;
-		buffer_size = serial->type->bulk_out_size;
-		if (!buffer_size)
-			buffer_size = usb_endpoint_maxp(endpoint);
-		port->bulk_out_size = buffer_size;
-		port->bulk_out_endpointAddress = endpoint->bEndpointAddress;
-
-		for (j = 0; j < ARRAY_SIZE(port->write_urbs); ++j) {
-			set_bit(j, &port->write_urbs_free);
-			port->write_urbs[j] = usb_alloc_urb(0, GFP_KERNEL);
-			if (!port->write_urbs[j])
-				goto probe_error;
-			port->bulk_out_buffers[j] = kmalloc(buffer_size,
-								GFP_KERNEL);
-			if (!port->bulk_out_buffers[j])
-				goto probe_error;
-			usb_fill_bulk_urb(port->write_urbs[j], dev,
-					usb_sndbulkpipe(dev,
-						endpoint->bEndpointAddress),
-					port->bulk_out_buffers[j], buffer_size,
-					serial->type->write_bulk_callback,
-					port);
-		}
-
-		port->write_urb = port->write_urbs[0];
-		port->bulk_out_buffer = port->bulk_out_buffers[0];
 	}
 
 	if (serial->type->read_int_callback) {
 		for (i = 0; i < epds->num_interrupt_in; ++i) {
-			endpoint = epds->interrupt_in[i];
-			port = serial->port[i];
-			port->interrupt_in_urb = usb_alloc_urb(0, GFP_KERNEL);
-			if (!port->interrupt_in_urb)
-				goto probe_error;
-			buffer_size = usb_endpoint_maxp(endpoint);
-			port->interrupt_in_endpointAddress =
-						endpoint->bEndpointAddress;
-			port->interrupt_in_buffer = kmalloc(buffer_size,
-								GFP_KERNEL);
-			if (!port->interrupt_in_buffer)
+			retval = setup_port_interrupt_in(serial->port[i],
+					epds->interrupt_in[i]);
+			if (retval)
 				goto probe_error;
-			usb_fill_int_urb(port->interrupt_in_urb, dev,
-				usb_rcvintpipe(dev,
-						endpoint->bEndpointAddress),
-				port->interrupt_in_buffer, buffer_size,
-				serial->type->read_int_callback, port,
-				endpoint->bInterval);
 		}
 	} else if (epds->num_interrupt_in) {
 		dev_dbg(ddev, "The device claims to support interrupt in transfers, but read_int_callback is not defined\n");
@@ -954,25 +1007,10 @@ static int usb_serial_probe(struct usb_interface *interface,
 
 	if (serial->type->write_int_callback) {
 		for (i = 0; i < epds->num_interrupt_out; ++i) {
-			endpoint = epds->interrupt_out[i];
-			port = serial->port[i];
-			port->interrupt_out_urb = usb_alloc_urb(0, GFP_KERNEL);
-			if (!port->interrupt_out_urb)
-				goto probe_error;
-			buffer_size = usb_endpoint_maxp(endpoint);
-			port->interrupt_out_size = buffer_size;
-			port->interrupt_out_endpointAddress =
-						endpoint->bEndpointAddress;
-			port->interrupt_out_buffer = kmalloc(buffer_size,
-								GFP_KERNEL);
-			if (!port->interrupt_out_buffer)
+			retval = setup_port_interrupt_out(serial->port[i],
+					epds->interrupt_out[i]);
+			if (retval)
 				goto probe_error;
-			usb_fill_int_urb(port->interrupt_out_urb, dev,
-				usb_sndintpipe(dev,
-						  endpoint->bEndpointAddress),
-				port->interrupt_out_buffer, buffer_size,
-				serial->type->write_int_callback, port,
-				endpoint->bInterval);
 		}
 	} else if (epds->num_interrupt_out) {
 		dev_dbg(ddev, "The device claims to support interrupt out transfers, but write_int_callback is not defined\n");