From: Ivan Vecera <ivecera@redhat.com>
Date: Tue, 22 Jan 2008 08:51:03 +0100
Subject: [usb] sierra MC8755: increase HSDPA performance
Message-id: 4795A067.6020509@redhat.com
O-Subject: Re: [RHEL5 PATCH] HSDPA Performance with Sierra MC8755
Bugzilla: 232885

BZ: https://bugzilla.redhat.com/bugzilla/show_bug.cgi?id=232885

Description (customer report):
We have some ThinkPads T60 and X60 with internal MiniPCI UMTS / HSDPA Card.
The Card is a Sierra MC8577 (USB Id 1199:6804). In RHEL5 there is a sierra
Kernel Module which supports this card in general but Lenovo has it's own
Product ID (6804). In Fedora 7 with Kernel vmlinuz-2.6.20-1.2986.fc7 there is a
newer Sierra Module that supports the card fine. Without the sierra Module we
can use the card with the usb-serial Kernel Module but only with about 40 KB/s
in Downlink. With the Sierra Module on Fedora 7 we get 140 - 150 KB/s!

Upstream status:
The patch is partly contained in version 2.6.19.
http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commitdiff;h=033a3fb980b041c5b1c865d3e9dce
9217d1dc94b
Only small portion of patch (device id table entries for product id 0x6804
is missing in upstream)

Testing:
I have built the kernel package with attached patch and sent it to customer to
test it. The customer confirmed that the patch solves its problem.

Regards,
Ivan

=====

diff --git a/drivers/usb/serial/sierra.c b/drivers/usb/serial/sierra.c
index d29638d..6b8501a 100644
--- a/drivers/usb/serial/sierra.c
+++ b/drivers/usb/serial/sierra.c
@@ -1,75 +1,664 @@
 /*
- * Sierra Wireless CDMA Wireless Serial USB driver
- *
- * Current Copy modified by: Kevin Lloyd <linux@sierrawireless.com>
- * Original Copyright (C) 2005-2006 Greg Kroah-Hartman <gregkh@suse.de>
- *
- *	This program is free software; you can redistribute it and/or
- *	modify it under the terms of the GNU General Public License version
- *	2 as published by the Free Software Foundation.
- */
+  USB Driver for Sierra Wireless
+
+  Copyright (C) 2006  Kevin Lloyd <linux@sierrawireless.com>
+
+  IMPORTANT DISCLAIMER: This driver is not commercially supported by
+  Sierra Wireless. Use at your own risk.
+
+  This driver is free software; you can redistribute it and/or modify
+  it under the terms of Version 2 of the GNU General Public License as
+  published by the Free Software Foundation.
+
+  Portions based on the option driver by Matthias Urlichs <smurf@smurf.noris.de>
+  Whom based his on the Keyspan driver by Hugh Blemings <hugh@blemings.org>
+
+  History:
+*/
+
+#define DRIVER_VERSION "v.1.0.5"
+#define DRIVER_AUTHOR "Kevin Lloyd <linux@sierrawireless.com>"
+#define DRIVER_DESC "USB Driver for Sierra Wireless USB modems"
 
 #include <linux/kernel.h>
-#include <linux/init.h>
+#include <linux/jiffies.h>
+#include <linux/errno.h>
 #include <linux/tty.h>
+#include <linux/tty_flip.h>
 #include <linux/module.h>
 #include <linux/usb.h>
 #include <linux/usb/serial.h>
 
+/* Function prototypes */
+static int  sierra_open(struct usb_serial_port *port, struct file *filp);
+static void sierra_close(struct usb_serial_port *port, struct file *filp);
+static int  sierra_startup(struct usb_serial *serial);
+static void sierra_shutdown(struct usb_serial *serial);
+static void sierra_rx_throttle(struct usb_serial_port *port);
+static void sierra_rx_unthrottle(struct usb_serial_port *port);
+static int  sierra_write_room(struct usb_serial_port *port);
+
+static void sierra_instat_callback(struct urb *urb, struct pt_regs *regs);
+
+static int sierra_write(struct usb_serial_port *port,
+			const unsigned char *buf, int count);
+
+static int  sierra_chars_in_buffer(struct usb_serial_port *port);
+static int  sierra_ioctl(struct usb_serial_port *port, struct file *file,
+			unsigned int cmd, unsigned long arg);
+static void sierra_set_termios(struct usb_serial_port *port,
+				struct termios *old);
+static void sierra_break_ctl(struct usb_serial_port *port, int break_state);
+static int  sierra_tiocmget(struct usb_serial_port *port, struct file *file);
+static int  sierra_tiocmset(struct usb_serial_port *port, struct file *file,
+				unsigned int set, unsigned int clear);
+static int  sierra_send_setup(struct usb_serial_port *port);
+
+static int sierra_set_power_state(struct usb_device *udev, __u16 swiState)
+{
+	int result;
+	dev_dbg(&udev->dev, "%s", "SET POWER STATE");
+	result = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
+			0x00,			/* __u8 request      */
+			0x40,			/* __u8 request type */
+			swiState,		/* __u16 value       */
+			0,			/* __u16 index       */
+			NULL,			/* void *data        */
+			0,			/* __u16 size 	     */
+			USB_CTRL_SET_TIMEOUT);	/* int timeout 	     */
+	return result;
+}
+
 static struct usb_device_id id_table [] = {
-	{ USB_DEVICE(0x1199, 0x0018) },	/* Sierra Wireless MC5720 */
 	{ USB_DEVICE(0x1199, 0x0020) },	/* Sierra Wireless MC5725 */
-	{ USB_DEVICE(0x1199, 0x0017) },	/* Sierra Wireless EM5625 */
 	{ USB_DEVICE(0x1199, 0x0019) },	/* Sierra Wireless AirCard 595 */
 	{ USB_DEVICE(0x1199, 0x6802) },	/* Sierra Wireless MC8755 */
 	{ USB_DEVICE(0x1199, 0x6803) },	/* Sierra Wireless MC8765 */
+	{ USB_DEVICE(0x1199, 0x6804) }, /* Sierra Wireless MC8755 */
+	{ USB_DEVICE(0x1199, 0x6812) },	/* Sierra Wireless MC8775 */
+	{ USB_DEVICE(0x1199, 0x6813) },	/* Sierra Wireless MC8775 */
+	{ USB_DEVICE(0x1199, 0x6820) },	/* Sierra Wireless AirCard 875 */
+	{ }
+};
+
+static struct usb_device_id id_table_3port [] = {
+	{ USB_DEVICE(0x1199, 0x0020) },	/* Sierra Wireless MC5725 */
+	{ USB_DEVICE(0x1199, 0x0019) },	/* Sierra Wireless AirCard 595 */
+	{ USB_DEVICE(0x1199, 0x6802) },	/* Sierra Wireless MC8755 */
+	{ USB_DEVICE(0x1199, 0x6803) },	/* Sierra Wireless MC8765 */
+	{ USB_DEVICE(0x1199, 0x6804) },	/* Sierra Wireless MC8755 */
 	{ USB_DEVICE(0x1199, 0x6812) },	/* Sierra Wireless MC8775 */
+	{ USB_DEVICE(0x1199, 0x6813) },	/* Sierra Wireless MC8775 */
 	{ USB_DEVICE(0x1199, 0x6820) },	/* Sierra Wireless AirCard 875 */
-	/* Following devices are supported in the airprime.c driver */
-	/* { USB_DEVICE(0x1199, 0x0112) }, */	/* Sierra Wireless AirCard 580 */
-	/* { USB_DEVICE(0x0F3D, 0x0112) }, */	/* AirPrime/Sierra PC 5220 */
 	{ }
 };
+
+
 MODULE_DEVICE_TABLE(usb, id_table);
 
 static struct usb_driver sierra_driver = {
-	.name =		"sierra_wireless",
-	.probe =	usb_serial_probe,
-	.disconnect =	usb_serial_disconnect,
-	.id_table =	id_table,
+	.name       = "sierra",
+	.probe      = usb_serial_probe,
+	.disconnect = usb_serial_disconnect,
+	.id_table   = id_table,
+	.no_dynamic_id = 	1,
 };
 
-static struct usb_serial_driver sierra_device = {
+static struct usb_serial_driver sierra_3port_device = {
 	.driver = {
-	.owner =		THIS_MODULE,
-	.name =			"Sierra_Wireless",
+		.owner =	THIS_MODULE,
+		.name =		"sierra3",
 	},
-	.id_table =		id_table,
-	.num_interrupt_in =	NUM_DONT_CARE,
-	.num_bulk_in =		NUM_DONT_CARE,
-	.num_bulk_out =		NUM_DONT_CARE,
-	.num_ports =		3,
+	.description       = "Sierra USB modem (3 port)",
+	.id_table          = id_table_3port,
+	.num_interrupt_in  = NUM_DONT_CARE,
+	.num_bulk_in       = 3,
+	.num_bulk_out      = 3,
+	.num_ports         = 3,
+	.open              = sierra_open,
+	.close             = sierra_close,
+	.write             = sierra_write,
+	.write_room        = sierra_write_room,
+	.chars_in_buffer   = sierra_chars_in_buffer,
+	.throttle          = sierra_rx_throttle,
+	.unthrottle        = sierra_rx_unthrottle,
+	.ioctl             = sierra_ioctl,
+	.set_termios       = sierra_set_termios,
+	.break_ctl         = sierra_break_ctl,
+	.tiocmget          = sierra_tiocmget,
+	.tiocmset          = sierra_tiocmset,
+	.attach            = sierra_startup,
+	.shutdown          = sierra_shutdown,
+	.read_int_callback = sierra_instat_callback,
+};
+
+#ifdef CONFIG_USB_DEBUG
+static int debug;
+#else
+#define debug 0
+#endif
+
+/* per port private data */
+
+#define N_IN_URB 4
+#define N_OUT_URB 1
+#define IN_BUFLEN 4096
+
+struct sierra_port_private {
+	spinlock_t lock;	/* lock the structure */
+	int outstanding_urbs;	/* number of out urbs in flight */
+
+	/* Input endpoints and buffer for this port */
+	struct urb *in_urbs[N_IN_URB];
+	char in_buffer[N_IN_URB][IN_BUFLEN];
+
+	/* Settings for the port */
+	int rts_state;	/* Handshaking pins (outputs) */
+	int dtr_state;
+	int cts_state;	/* Handshaking pins (inputs) */
+	int dsr_state;
+	int dcd_state;
+	int ri_state;
 };
 
+/* Functions used by new usb-serial code. */
 static int __init sierra_init(void)
 {
 	int retval;
-
-	retval = usb_serial_register(&sierra_device);
+	retval = usb_serial_register(&sierra_3port_device);
 	if (retval)
-		return retval;
+		goto failed_3port_device_register;
+
 	retval = usb_register(&sierra_driver);
 	if (retval)
-		usb_serial_deregister(&sierra_device);
+		goto failed_driver_register;
+
+	info(DRIVER_DESC ": " DRIVER_VERSION);
+
+	return 0;
+
+failed_driver_register:
+	usb_serial_deregister(&sierra_3port_device);
+failed_3port_device_register:
 	return retval;
 }
 
 static void __exit sierra_exit(void)
 {
-	usb_deregister(&sierra_driver);
-	usb_serial_deregister(&sierra_device);
+	usb_deregister (&sierra_driver);
+	usb_serial_deregister(&sierra_3port_device);
 }
 
 module_init(sierra_init);
 module_exit(sierra_exit);
+
+static void sierra_rx_throttle(struct usb_serial_port *port)
+{
+	dbg("%s", __FUNCTION__);
+}
+
+static void sierra_rx_unthrottle(struct usb_serial_port *port)
+{
+	dbg("%s", __FUNCTION__);
+}
+
+static void sierra_break_ctl(struct usb_serial_port *port, int break_state)
+{
+	/* Unfortunately, I don't know how to send a break */
+	dbg("%s", __FUNCTION__);
+}
+
+static void sierra_set_termios(struct usb_serial_port *port,
+			struct termios *old_termios)
+{
+	dbg("%s", __FUNCTION__);
+
+	sierra_send_setup(port);
+}
+
+static int sierra_tiocmget(struct usb_serial_port *port, struct file *file)
+{
+	unsigned int value;
+	struct sierra_port_private *portdata;
+
+	portdata = usb_get_serial_port_data(port);
+
+	value = ((portdata->rts_state) ? TIOCM_RTS : 0) |
+		((portdata->dtr_state) ? TIOCM_DTR : 0) |
+		((portdata->cts_state) ? TIOCM_CTS : 0) |
+		((portdata->dsr_state) ? TIOCM_DSR : 0) |
+		((portdata->dcd_state) ? TIOCM_CAR : 0) |
+		((portdata->ri_state) ? TIOCM_RNG : 0);
+
+	return value;
+}
+
+static int sierra_tiocmset(struct usb_serial_port *port, struct file *file,
+			unsigned int set, unsigned int clear)
+{
+	struct sierra_port_private *portdata;
+
+	portdata = usb_get_serial_port_data(port);
+
+	if (set & TIOCM_RTS)
+		portdata->rts_state = 1;
+	if (set & TIOCM_DTR)
+		portdata->dtr_state = 1;
+
+	if (clear & TIOCM_RTS)
+		portdata->rts_state = 0;
+	if (clear & TIOCM_DTR)
+		portdata->dtr_state = 0;
+	return sierra_send_setup(port);
+}
+
+static int sierra_ioctl(struct usb_serial_port *port, struct file *file,
+			unsigned int cmd, unsigned long arg)
+{
+	return -ENOIOCTLCMD;
+}
+
+static void sierra_outdat_callback(struct urb *urb, struct pt_regs *regs)
+{
+	struct usb_serial_port *port = urb->context;
+	struct sierra_port_private *portdata = usb_get_serial_port_data(port);
+	int status = urb->status;
+	unsigned long flags;
+
+	dbg("%s - port %d", __FUNCTION__, port->number);
+
+	/* free up the transfer buffer, as usb_free_urb() does not do this */
+	kfree(urb->transfer_buffer);
+
+	if (status)
+		dbg("%s - nonzero write bulk status received: %d",
+		    __FUNCTION__, status);
+
+	spin_lock_irqsave(&portdata->lock, flags);
+	--portdata->outstanding_urbs;
+	spin_unlock_irqrestore(&portdata->lock, flags);
+
+	usb_serial_port_softint(port);
+}
+
+/* Write */
+static int sierra_write(struct usb_serial_port *port,
+			const unsigned char *buf, int count)
+{
+	struct sierra_port_private *portdata = usb_get_serial_port_data(port);
+	struct usb_serial *serial = port->serial;
+	unsigned long flags;
+	unsigned char *buffer;
+	struct urb *urb;
+	int status;
+
+	portdata = usb_get_serial_port_data(port);
+
+	dbg("%s: write (%d chars)", __FUNCTION__, count);
+
+	spin_lock_irqsave(&portdata->lock, flags);
+	if (portdata->outstanding_urbs > N_OUT_URB) {
+		spin_unlock_irqrestore(&portdata->lock, flags);
+		dbg("%s - write limit hit\n", __FUNCTION__);
+		return 0;
+	}
+	portdata->outstanding_urbs++;
+	spin_unlock_irqrestore(&portdata->lock, flags);
+
+	buffer = kmalloc(count, GFP_ATOMIC);
+	if (!buffer) {
+		dev_err(&port->dev, "out of memory\n");
+		count = -ENOMEM;
+		goto error_no_buffer;
+	}
+
+	urb = usb_alloc_urb(0, GFP_ATOMIC);
+	if (!urb) {
+		dev_err(&port->dev, "no more free urbs\n");
+		count = -ENOMEM;
+		goto error_no_urb;
+	}
+
+	memcpy(buffer, buf, count);
+
+	usb_serial_debug_data(debug, &port->dev, __FUNCTION__, count, buffer);
+
+	usb_fill_bulk_urb(urb, serial->dev,
+			  usb_sndbulkpipe(serial->dev,
+					  port->bulk_out_endpointAddress),
+			  buffer, count, sierra_outdat_callback, port);
+
+	/* send it down the pipe */
+	status = usb_submit_urb(urb, GFP_ATOMIC);
+	if (status) {
+		dev_err(&port->dev, "%s - usb_submit_urb(write bulk) failed "
+			"with status = %d\n", __FUNCTION__, status);
+		count = status;
+		goto error;
+	}
+
+	/* we are done with this urb, so let the host driver
+	 * really free it when it is finished with it */
+	usb_free_urb(urb);
+
+	return count;
+error:
+	usb_free_urb(urb);
+error_no_urb:
+	kfree(buffer);
+error_no_buffer:
+	spin_lock_irqsave(&portdata->lock, flags);
+	--portdata->outstanding_urbs;
+	spin_unlock_irqrestore(&portdata->lock, flags);
+	return count;
+}
+
+static void sierra_indat_callback(struct urb *urb, struct pt_regs *regs)
+{
+	int err;
+	int endpoint;
+	struct usb_serial_port *port;
+	struct tty_struct *tty;
+	unsigned char *data = urb->transfer_buffer;
+
+	dbg("%s: %p", __FUNCTION__, urb);
+
+	endpoint = usb_pipeendpoint(urb->pipe);
+	port = (struct usb_serial_port *) urb->context;
+
+	if (urb->status) {
+		dbg("%s: nonzero status: %d on endpoint %02x.",
+		    __FUNCTION__, urb->status, endpoint);
+	} else {
+		tty = port->tty;
+		if (tty && urb->actual_length) {
+			tty_buffer_request_room(tty, urb->actual_length);
+			tty_insert_flip_string(tty, data, urb->actual_length);
+			tty_flip_buffer_push(tty);
+		} else {
+			dbg("%s: empty read urb received", __FUNCTION__);
+		}
+
+		/* Resubmit urb so we continue receiving */
+		if (port->open_count && urb->status != -ESHUTDOWN) {
+			err = usb_submit_urb(urb, GFP_ATOMIC);
+			if (err)
+				dev_err(&port->dev, "resubmit read urb failed."
+					"(%d)", err);
+		}
+	}
+	return;
+}
+
+static void sierra_instat_callback(struct urb *urb, struct pt_regs *regs)
+{
+	int err;
+	struct usb_serial_port *port = (struct usb_serial_port *) urb->context;
+	struct sierra_port_private *portdata = usb_get_serial_port_data(port);
+	struct usb_serial *serial = port->serial;
+
+	dbg("%s", __FUNCTION__);
+	dbg("%s: urb %p port %p has data %p", __FUNCTION__,urb,port,portdata);
+
+	if (urb->status == 0) {
+		struct usb_ctrlrequest *req_pkt =
+				(struct usb_ctrlrequest *)urb->transfer_buffer;
+
+		if (!req_pkt) {
+			dbg("%s: NULL req_pkt\n", __FUNCTION__);
+			return;
+		}
+		if ((req_pkt->bRequestType == 0xA1) &&
+				(req_pkt->bRequest == 0x20)) {
+			int old_dcd_state;
+			unsigned char signals = *((unsigned char *)
+					urb->transfer_buffer +
+					sizeof(struct usb_ctrlrequest));
+
+			dbg("%s: signal x%x", __FUNCTION__, signals);
+
+			old_dcd_state = portdata->dcd_state;
+			portdata->cts_state = 1;
+			portdata->dcd_state = ((signals & 0x01) ? 1 : 0);
+			portdata->dsr_state = ((signals & 0x02) ? 1 : 0);
+			portdata->ri_state = ((signals & 0x08) ? 1 : 0);
+
+			if (port->tty && !C_CLOCAL(port->tty) &&
+					old_dcd_state && !portdata->dcd_state)
+				tty_hangup(port->tty);
+		} else {
+			dbg("%s: type %x req %x", __FUNCTION__,
+				req_pkt->bRequestType,req_pkt->bRequest);
+		}
+	} else
+		dbg("%s: error %d", __FUNCTION__, urb->status);
+
+	/* Resubmit urb so we continue receiving IRQ data */
+	if (urb->status != -ESHUTDOWN) {
+		urb->dev = serial->dev;
+		err = usb_submit_urb(urb, GFP_ATOMIC);
+		if (err)
+			dbg("%s: resubmit intr urb failed. (%d)",
+				__FUNCTION__, err);
+	}
+}
+
+static int sierra_write_room(struct usb_serial_port *port)
+{
+	struct sierra_port_private *portdata = usb_get_serial_port_data(port);
+	unsigned long flags;
+
+	dbg("%s - port %d", __FUNCTION__, port->number);
+
+	/* try to give a good number back based on if we have any free urbs at
+	 * this point in time */
+	spin_lock_irqsave(&portdata->lock, flags);
+	if (portdata->outstanding_urbs > N_OUT_URB * 2 / 3) {
+		spin_unlock_irqrestore(&portdata->lock, flags);
+		dbg("%s - write limit hit\n", __FUNCTION__);
+		return 0;
+	}
+	spin_unlock_irqrestore(&portdata->lock, flags);
+
+	return 2048;
+}
+
+static int sierra_chars_in_buffer(struct usb_serial_port *port)
+{
+	dbg("%s - port %d", __FUNCTION__, port->number);
+
+	/*
+	 * We can't really account for how much data we
+	 * have sent out, but hasn't made it through to the
+	 * device as we can't see the backend here, so just
+	 * tell the tty layer that everything is flushed.
+	 */
+	return 0;
+}
+
+static int sierra_open(struct usb_serial_port *port, struct file *filp)
+{
+	struct sierra_port_private *portdata;
+	struct usb_serial *serial = port->serial;
+	int i;
+	struct urb *urb;
+	int result;
+
+	portdata = usb_get_serial_port_data(port);
+
+	dbg("%s", __FUNCTION__);
+
+	/* Set some sane defaults */
+	portdata->rts_state = 1;
+	portdata->dtr_state = 1;
+
+	/* Reset low level data toggle and start reading from endpoints */
+	for (i = 0; i < N_IN_URB; i++) {
+		urb = portdata->in_urbs[i];
+		if (!urb)
+			continue;
+		if (urb->dev != serial->dev) {
+			dbg("%s: dev %p != %p", __FUNCTION__,
+				urb->dev, serial->dev);
+			continue;
+		}
+
+		/*
+		 * make sure endpoint data toggle is synchronized with the
+		 * device
+		 */
+		usb_clear_halt(urb->dev, urb->pipe);
+
+		result = usb_submit_urb(urb, GFP_KERNEL);
+		if (result) {
+			dev_err(&port->dev, "submit urb %d failed (%d) %d",
+				i, result, urb->transfer_buffer_length);
+		}
+	}
+
+	port->tty->low_latency = 1;
+
+	sierra_send_setup(port);
+
+	/* start up the interrupt endpoint if we have one */
+	if (port->interrupt_in_urb) {
+		result = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
+		if (result)
+			dev_err(&port->dev, "submit irq_in urb failed %d",
+				result);
+	}
+	return 0;
+}
+
+static void sierra_close(struct usb_serial_port *port, struct file *filp)
+{
+	int i;
+	struct usb_serial *serial = port->serial;
+	struct sierra_port_private *portdata;
+
+	dbg("%s", __FUNCTION__);
+	portdata = usb_get_serial_port_data(port);
+
+	portdata->rts_state = 0;
+	portdata->dtr_state = 0;
+
+	if (serial->dev) {
+		sierra_send_setup(port);
+
+		/* Stop reading/writing urbs */
+		for (i = 0; i < N_IN_URB; i++)
+			usb_kill_urb(portdata->in_urbs[i]);
+	}
+
+	usb_kill_urb(port->interrupt_in_urb);
+
+	port->tty = NULL;
+}
+
+static int sierra_send_setup(struct usb_serial_port *port)
+{
+	struct usb_serial *serial = port->serial;
+	struct sierra_port_private *portdata;
+
+	dbg("%s", __FUNCTION__);
+
+	portdata = usb_get_serial_port_data(port);
+
+	if (port->tty) {
+		int val = 0;
+		if (portdata->dtr_state)
+			val |= 0x01;
+		if (portdata->rts_state)
+			val |= 0x02;
+
+		return usb_control_msg(serial->dev,
+				usb_rcvctrlpipe(serial->dev, 0),
+				0x22,0x21,val,0,NULL,0,USB_CTRL_SET_TIMEOUT);
+	}
+
+	return 0;
+}
+
+static int sierra_startup(struct usb_serial *serial)
+{
+	struct usb_serial_port *port;
+	struct sierra_port_private *portdata;
+	struct urb *urb;
+	int i;
+	int j;
+
+	dbg("%s", __FUNCTION__);
+
+	/*Set Device mode to D0 */
+	sierra_set_power_state(serial->dev, 0x0000);
+
+	/* Now setup per port private data */
+	for (i = 0; i < serial->num_ports; i++) {
+		port = serial->port[i];
+		portdata = kzalloc(sizeof(*portdata), GFP_KERNEL);
+		if (!portdata) {
+			dbg("%s: kmalloc for sierra_port_private (%d) failed!.",
+					__FUNCTION__, i);
+			return -ENOMEM;
+		}
+		spin_lock_init(&portdata->lock);
+
+		usb_set_serial_port_data(port, portdata);
+
+		/* initialize the in urbs */
+		for (j = 0; j < N_IN_URB; ++j) {
+			urb = usb_alloc_urb(0, GFP_KERNEL);
+			if (urb == NULL) {
+				dbg("%s: alloc for in port failed.",
+				    __FUNCTION__);
+				continue;
+			}
+			/* Fill URB using supplied data. */
+			usb_fill_bulk_urb(urb, serial->dev,
+					  usb_rcvbulkpipe(serial->dev,
+						port->bulk_in_endpointAddress),
+					  portdata->in_buffer[j], IN_BUFLEN,
+					  sierra_indat_callback, port);
+			portdata->in_urbs[j] = urb;
+		}
+	}
+
+	return 0;
+}
+
+static void sierra_shutdown(struct usb_serial *serial)
+{
+	int i, j;
+	struct usb_serial_port *port;
+	struct sierra_port_private *portdata;
+
+	dbg("%s", __FUNCTION__);
+
+	for (i = 0; i < serial->num_ports; ++i) {
+		port = serial->port[i];
+		if (!port)
+			continue;
+		portdata = usb_get_serial_port_data(port);
+		if (!portdata)
+			continue;
+
+		for (j = 0; j < N_IN_URB; j++) {
+			usb_kill_urb(portdata->in_urbs[j]);
+			usb_free_urb(portdata->in_urbs[j]);
+			portdata->in_urbs[j] = NULL;
+		}
+		kfree(portdata);
+		usb_set_serial_port_data(port, NULL);
+	}
+}
+
+MODULE_AUTHOR(DRIVER_AUTHOR);
+MODULE_DESCRIPTION(DRIVER_DESC);
+MODULE_VERSION(DRIVER_VERSION);
 MODULE_LICENSE("GPL");
+
+#ifdef CONFIG_USB_DEBUG
+module_param(debug, bool, S_IRUGO | S_IWUSR);
+MODULE_PARM_DESC(debug, "Debug messages");
+#endif
+