blob: ab0f3226158b0d6ed735c041931a6b80ae869afb [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * LEGO USB Tower driver
3 *
4 * Copyright (C) 2003 David Glance <davidgsf@sourceforge.net>
5 * 2001-2004 Juergen Stuber <starblue@users.sourceforge.net>
6 *
7 * This program is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU General Public License as
9 * published by the Free Software Foundation; either version 2 of
10 * the License, or (at your option) any later version.
11 *
12 * derived from USB Skeleton driver - 0.5
13 * Copyright (C) 2001 Greg Kroah-Hartman (greg@kroah.com)
14 *
15 * History:
16 *
17 * 2001-10-13 - 0.1 js
18 * - first version
19 * 2001-11-03 - 0.2 js
20 * - simplified buffering, one-shot URBs for writing
21 * 2001-11-10 - 0.3 js
22 * - removed IOCTL (setting power/mode is more complicated, postponed)
23 * 2001-11-28 - 0.4 js
24 * - added vendor commands for mode of operation and power level in open
25 * 2001-12-04 - 0.5 js
26 * - set IR mode by default (by oversight 0.4 set VLL mode)
27 * 2002-01-11 - 0.5? pcchan
28 * - make read buffer reusable and work around bytes_to_write issue between
29 * uhci and legusbtower
30 * 2002-09-23 - 0.52 david (david@csse.uwa.edu.au)
31 * - imported into lejos project
32 * - changed wake_up to wake_up_interruptible
33 * - changed to use lego0 rather than tower0
Harvey Harrison441b62c2008-03-03 16:08:34 -080034 * - changed dbg() to use __func__ rather than deprecated __func__
Linus Torvalds1da177e2005-04-16 15:20:36 -070035 * 2003-01-12 - 0.53 david (david@csse.uwa.edu.au)
36 * - changed read and write to write everything or
37 * timeout (from a patch by Chris Riesen and Brett Thaeler driver)
38 * - added ioctl functionality to set timeouts
39 * 2003-07-18 - 0.54 davidgsf (david@csse.uwa.edu.au)
40 * - initial import into LegoUSB project
41 * - merge of existing LegoUSB.c driver
42 * 2003-07-18 - 0.56 davidgsf (david@csse.uwa.edu.au)
43 * - port to 2.6 style driver
44 * 2004-02-29 - 0.6 Juergen Stuber <starblue@users.sourceforge.net>
45 * - fix locking
46 * - unlink read URBs which are no longer needed
47 * - allow increased buffer size, eliminates need for timeout on write
48 * - have read URB running continuously
49 * - added poll
50 * - forbid seeking
51 * - added nonblocking I/O
Harvey Harrison441b62c2008-03-03 16:08:34 -080052 * - changed back __func__ to __func__
Linus Torvalds1da177e2005-04-16 15:20:36 -070053 * - read and log tower firmware version
54 * - reset tower on probe, avoids failure of first write
55 * 2004-03-09 - 0.7 Juergen Stuber <starblue@users.sourceforge.net>
56 * - timeout read now only after inactivity, shorten default accordingly
57 * 2004-03-11 - 0.8 Juergen Stuber <starblue@users.sourceforge.net>
58 * - log major, minor instead of possibly confusing device filename
59 * - whitespace cleanup
60 * 2004-03-12 - 0.9 Juergen Stuber <starblue@users.sourceforge.net>
61 * - normalize whitespace in debug messages
62 * - take care about endianness in control message responses
63 * 2004-03-13 - 0.91 Juergen Stuber <starblue@users.sourceforge.net>
64 * - make default intervals longer to accommodate current EHCI driver
65 * 2004-03-19 - 0.92 Juergen Stuber <starblue@users.sourceforge.net>
66 * - replaced atomic_t by memory barriers
67 * 2004-04-21 - 0.93 Juergen Stuber <starblue@users.sourceforge.net>
68 * - wait for completion of write urb in release (needed for remotecontrol)
69 * - corrected poll for write direction (missing negation)
70 * 2004-04-22 - 0.94 Juergen Stuber <starblue@users.sourceforge.net>
71 * - make device locking interruptible
72 * 2004-04-30 - 0.95 Juergen Stuber <starblue@users.sourceforge.net>
73 * - check for valid udev on resubmitting and unlinking urbs
74 * 2004-08-03 - 0.96 Juergen Stuber <starblue@users.sourceforge.net>
75 * - move reset into open to clean out spurious data
76 */
77
Linus Torvalds1da177e2005-04-16 15:20:36 -070078#include <linux/kernel.h>
79#include <linux/errno.h>
80#include <linux/init.h>
81#include <linux/slab.h>
82#include <linux/module.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070083#include <linux/completion.h>
Arjan van de Ven4186ecf2006-01-11 15:55:29 +010084#include <linux/mutex.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070085#include <asm/uaccess.h>
86#include <linux/usb.h>
87#include <linux/poll.h>
88
89
90#ifdef CONFIG_USB_DEBUG
91 static int debug = 4;
92#else
93 static int debug = 0;
94#endif
95
96/* Use our own dbg macro */
97#undef dbg
98#define dbg(lvl, format, arg...) do { if (debug >= lvl) printk(KERN_DEBUG __FILE__ ": " format "\n", ## arg); } while (0)
99
100
101/* Version Information */
102#define DRIVER_VERSION "v0.96"
103#define DRIVER_AUTHOR "Juergen Stuber <starblue@sourceforge.net>"
104#define DRIVER_DESC "LEGO USB Tower Driver"
105
106/* Module parameters */
107module_param(debug, int, S_IRUGO | S_IWUSR);
108MODULE_PARM_DESC(debug, "Debug enabled or not");
109
110/* The defaults are chosen to work with the latest versions of leJOS and NQC.
111 */
112
113/* Some legacy software likes to receive packets in one piece.
114 * In this case read_buffer_size should exceed the maximal packet length
115 * (417 for datalog uploads), and packet_timeout should be set.
116 */
117static int read_buffer_size = 480;
118module_param(read_buffer_size, int, 0);
119MODULE_PARM_DESC(read_buffer_size, "Read buffer size");
120
121/* Some legacy software likes to send packets in one piece.
122 * In this case write_buffer_size should exceed the maximal packet length
123 * (417 for firmware and program downloads).
124 * A problem with long writes is that the following read may time out
125 * if the software is not prepared to wait long enough.
126 */
127static int write_buffer_size = 480;
128module_param(write_buffer_size, int, 0);
129MODULE_PARM_DESC(write_buffer_size, "Write buffer size");
130
131/* Some legacy software expects reads to contain whole LASM packets.
132 * To achieve this, characters which arrive before a packet timeout
133 * occurs will be returned in a single read operation.
134 * A problem with long reads is that the software may time out
135 * if it is not prepared to wait long enough.
136 * The packet timeout should be greater than the time between the
137 * reception of subsequent characters, which should arrive about
138 * every 5ms for the standard 2400 baud.
139 * Set it to 0 to disable.
140 */
141static int packet_timeout = 50;
142module_param(packet_timeout, int, 0);
143MODULE_PARM_DESC(packet_timeout, "Packet timeout in ms");
144
145/* Some legacy software expects blocking reads to time out.
146 * Timeout occurs after the specified time of read and write inactivity.
147 * Set it to 0 to disable.
148 */
149static int read_timeout = 200;
150module_param(read_timeout, int, 0);
151MODULE_PARM_DESC(read_timeout, "Read timeout in ms");
152
153/* As of kernel version 2.6.4 ehci-hcd uses an
154 * "only one interrupt transfer per frame" shortcut
155 * to simplify the scheduling of periodic transfers.
156 * This conflicts with our standard 1ms intervals for in and out URBs.
157 * We use default intervals of 2ms for in and 8ms for out transfers,
158 * which is fast enough for 2400 baud and allows a small additional load.
159 * Increase the interval to allow more devices that do interrupt transfers,
160 * or set to 0 to use the standard interval from the endpoint descriptors.
161 */
162static int interrupt_in_interval = 2;
163module_param(interrupt_in_interval, int, 0);
164MODULE_PARM_DESC(interrupt_in_interval, "Interrupt in interval in ms");
165
166static int interrupt_out_interval = 8;
167module_param(interrupt_out_interval, int, 0);
168MODULE_PARM_DESC(interrupt_out_interval, "Interrupt out interval in ms");
169
170/* Define these values to match your device */
171#define LEGO_USB_TOWER_VENDOR_ID 0x0694
172#define LEGO_USB_TOWER_PRODUCT_ID 0x0001
173
174/* Vendor requests */
175#define LEGO_USB_TOWER_REQUEST_RESET 0x04
176#define LEGO_USB_TOWER_REQUEST_GET_VERSION 0xFD
177
178struct tower_reset_reply {
179 __le16 size; /* little-endian */
180 __u8 err_code;
181 __u8 spare;
182} __attribute__ ((packed));
183
184struct tower_get_version_reply {
185 __le16 size; /* little-endian */
186 __u8 err_code;
187 __u8 spare;
188 __u8 major;
189 __u8 minor;
190 __le16 build_no; /* little-endian */
191} __attribute__ ((packed));
192
193
194/* table of devices that work with this driver */
195static struct usb_device_id tower_table [] = {
196 { USB_DEVICE(LEGO_USB_TOWER_VENDOR_ID, LEGO_USB_TOWER_PRODUCT_ID) },
197 { } /* Terminating entry */
198};
199
200MODULE_DEVICE_TABLE (usb, tower_table);
Oliver Neukum78663ec2007-10-25 15:48:39 +0200201static DEFINE_MUTEX(open_disc_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700202
203#define LEGO_USB_TOWER_MINOR_BASE 160
204
205
206/* Structure to hold all of our device specific stuff */
207struct lego_usb_tower {
Daniel Walker18bcbcf2008-01-11 08:45:44 -0800208 struct mutex lock; /* locks this structure */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700209 struct usb_device* udev; /* save off the usb device pointer */
210 unsigned char minor; /* the starting minor number for this device */
211
212 int open_count; /* number of times this port has been opened */
213
214 char* read_buffer;
215 size_t read_buffer_length; /* this much came in */
216 size_t read_packet_length; /* this much will be returned on read */
217 spinlock_t read_buffer_lock;
218 int packet_timeout_jiffies;
219 unsigned long read_last_arrival;
220
221 wait_queue_head_t read_wait;
222 wait_queue_head_t write_wait;
223
224 char* interrupt_in_buffer;
225 struct usb_endpoint_descriptor* interrupt_in_endpoint;
226 struct urb* interrupt_in_urb;
227 int interrupt_in_interval;
228 int interrupt_in_running;
229 int interrupt_in_done;
230
231 char* interrupt_out_buffer;
232 struct usb_endpoint_descriptor* interrupt_out_endpoint;
233 struct urb* interrupt_out_urb;
234 int interrupt_out_interval;
235 int interrupt_out_busy;
236
237};
238
239
240/* local function prototypes */
241static ssize_t tower_read (struct file *file, char __user *buffer, size_t count, loff_t *ppos);
242static ssize_t tower_write (struct file *file, const char __user *buffer, size_t count, loff_t *ppos);
243static inline void tower_delete (struct lego_usb_tower *dev);
244static int tower_open (struct inode *inode, struct file *file);
245static int tower_release (struct inode *inode, struct file *file);
246static unsigned int tower_poll (struct file *file, poll_table *wait);
247static loff_t tower_llseek (struct file *file, loff_t off, int whence);
248
249static void tower_abort_transfers (struct lego_usb_tower *dev);
250static void tower_check_for_read_packet (struct lego_usb_tower *dev);
David Howells7d12e782006-10-05 14:55:46 +0100251static void tower_interrupt_in_callback (struct urb *urb);
252static void tower_interrupt_out_callback (struct urb *urb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700253
254static int tower_probe (struct usb_interface *interface, const struct usb_device_id *id);
255static void tower_disconnect (struct usb_interface *interface);
256
257
Linus Torvalds1da177e2005-04-16 15:20:36 -0700258/* file operations needed when we register this driver */
Luiz Fernando N. Capitulino066202d2006-08-05 20:37:11 -0300259static const struct file_operations tower_fops = {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700260 .owner = THIS_MODULE,
261 .read = tower_read,
262 .write = tower_write,
263 .open = tower_open,
264 .release = tower_release,
265 .poll = tower_poll,
266 .llseek = tower_llseek,
267};
268
269/*
270 * usb class driver info in order to get a minor number from the usb core,
Greg Kroah-Hartmand6e5bcf2005-06-20 21:15:16 -0700271 * and to have the device registered with the driver core
Linus Torvalds1da177e2005-04-16 15:20:36 -0700272 */
273static struct usb_class_driver tower_class = {
Greg Kroah-Hartmand6e5bcf2005-06-20 21:15:16 -0700274 .name = "legousbtower%d",
Linus Torvalds1da177e2005-04-16 15:20:36 -0700275 .fops = &tower_fops,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700276 .minor_base = LEGO_USB_TOWER_MINOR_BASE,
277};
278
279
280/* usb specific object needed to register this driver with the usb subsystem */
281static struct usb_driver tower_driver = {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700282 .name = "legousbtower",
283 .probe = tower_probe,
284 .disconnect = tower_disconnect,
285 .id_table = tower_table,
286};
287
288
289/**
290 * lego_usb_tower_debug_data
291 */
292static inline void lego_usb_tower_debug_data (int level, const char *function, int size, const unsigned char *data)
293{
294 int i;
295
296 if (debug < level)
297 return;
298
299 printk (KERN_DEBUG __FILE__": %s - length = %d, data = ", function, size);
300 for (i = 0; i < size; ++i) {
301 printk ("%.2x ", data[i]);
302 }
303 printk ("\n");
304}
305
306
307/**
308 * tower_delete
309 */
310static inline void tower_delete (struct lego_usb_tower *dev)
311{
Harvey Harrison441b62c2008-03-03 16:08:34 -0800312 dbg(2, "%s: enter", __func__);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700313
314 tower_abort_transfers (dev);
315
316 /* free data structures */
Mariusz Kozlowskif53510e2006-11-08 15:36:14 +0100317 usb_free_urb(dev->interrupt_in_urb);
318 usb_free_urb(dev->interrupt_out_urb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700319 kfree (dev->read_buffer);
320 kfree (dev->interrupt_in_buffer);
321 kfree (dev->interrupt_out_buffer);
322 kfree (dev);
323
Harvey Harrison441b62c2008-03-03 16:08:34 -0800324 dbg(2, "%s: leave", __func__);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700325}
326
327
328/**
329 * tower_open
330 */
331static int tower_open (struct inode *inode, struct file *file)
332{
333 struct lego_usb_tower *dev = NULL;
334 int subminor;
335 int retval = 0;
336 struct usb_interface *interface;
337 struct tower_reset_reply reset_reply;
338 int result;
339
Harvey Harrison441b62c2008-03-03 16:08:34 -0800340 dbg(2, "%s: enter", __func__);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700341
342 nonseekable_open(inode, file);
343 subminor = iminor(inode);
344
Linus Torvalds1da177e2005-04-16 15:20:36 -0700345 interface = usb_find_interface (&tower_driver, subminor);
346
347 if (!interface) {
348 err ("%s - error, can't find device for minor %d",
Harvey Harrison441b62c2008-03-03 16:08:34 -0800349 __func__, subminor);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700350 retval = -ENODEV;
Alan Sternd4ead162007-05-22 11:46:41 -0400351 goto exit;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700352 }
353
Oliver Neukum78663ec2007-10-25 15:48:39 +0200354 mutex_lock(&open_disc_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700355 dev = usb_get_intfdata(interface);
356
357 if (!dev) {
Oliver Neukum78663ec2007-10-25 15:48:39 +0200358 mutex_unlock(&open_disc_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700359 retval = -ENODEV;
Alan Sternd4ead162007-05-22 11:46:41 -0400360 goto exit;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700361 }
362
363 /* lock this device */
Daniel Walker18bcbcf2008-01-11 08:45:44 -0800364 if (mutex_lock_interruptible(&dev->lock)) {
Oliver Neukum78663ec2007-10-25 15:48:39 +0200365 mutex_unlock(&open_disc_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700366 retval = -ERESTARTSYS;
Alan Sternd4ead162007-05-22 11:46:41 -0400367 goto exit;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700368 }
369
Oliver Neukum78663ec2007-10-25 15:48:39 +0200370
Linus Torvalds1da177e2005-04-16 15:20:36 -0700371 /* allow opening only once */
372 if (dev->open_count) {
Oliver Neukum78663ec2007-10-25 15:48:39 +0200373 mutex_unlock(&open_disc_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700374 retval = -EBUSY;
375 goto unlock_exit;
376 }
377 dev->open_count = 1;
Oliver Neukum78663ec2007-10-25 15:48:39 +0200378 mutex_unlock(&open_disc_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700379
380 /* reset the tower */
381 result = usb_control_msg (dev->udev,
382 usb_rcvctrlpipe(dev->udev, 0),
383 LEGO_USB_TOWER_REQUEST_RESET,
384 USB_TYPE_VENDOR | USB_DIR_IN | USB_RECIP_DEVICE,
385 0,
386 0,
387 &reset_reply,
388 sizeof(reset_reply),
389 1000);
390 if (result < 0) {
391 err("LEGO USB Tower reset control request failed");
392 retval = result;
393 goto unlock_exit;
394 }
395
396 /* initialize in direction */
397 dev->read_buffer_length = 0;
398 dev->read_packet_length = 0;
399 usb_fill_int_urb (dev->interrupt_in_urb,
400 dev->udev,
401 usb_rcvintpipe(dev->udev, dev->interrupt_in_endpoint->bEndpointAddress),
402 dev->interrupt_in_buffer,
403 le16_to_cpu(dev->interrupt_in_endpoint->wMaxPacketSize),
404 tower_interrupt_in_callback,
405 dev,
406 dev->interrupt_in_interval);
407
408 dev->interrupt_in_running = 1;
409 dev->interrupt_in_done = 0;
410 mb();
411
412 retval = usb_submit_urb (dev->interrupt_in_urb, GFP_KERNEL);
413 if (retval) {
414 err("Couldn't submit interrupt_in_urb %d", retval);
415 dev->interrupt_in_running = 0;
416 dev->open_count = 0;
417 goto unlock_exit;
418 }
419
420 /* save device in the file's private structure */
421 file->private_data = dev;
422
423unlock_exit:
Daniel Walker18bcbcf2008-01-11 08:45:44 -0800424 mutex_unlock(&dev->lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700425
Alan Sternd4ead162007-05-22 11:46:41 -0400426exit:
Harvey Harrison441b62c2008-03-03 16:08:34 -0800427 dbg(2, "%s: leave, return value %d ", __func__, retval);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700428
429 return retval;
430}
431
432/**
433 * tower_release
434 */
435static int tower_release (struct inode *inode, struct file *file)
436{
437 struct lego_usb_tower *dev;
438 int retval = 0;
439
Harvey Harrison441b62c2008-03-03 16:08:34 -0800440 dbg(2, "%s: enter", __func__);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700441
442 dev = (struct lego_usb_tower *)file->private_data;
443
444 if (dev == NULL) {
Harvey Harrison441b62c2008-03-03 16:08:34 -0800445 dbg(1, "%s: object is NULL", __func__);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700446 retval = -ENODEV;
Oliver Neukum78663ec2007-10-25 15:48:39 +0200447 goto exit_nolock;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700448 }
449
Oliver Neukum78663ec2007-10-25 15:48:39 +0200450 mutex_lock(&open_disc_mutex);
Daniel Walker18bcbcf2008-01-11 08:45:44 -0800451 if (mutex_lock_interruptible(&dev->lock)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700452 retval = -ERESTARTSYS;
453 goto exit;
454 }
455
456 if (dev->open_count != 1) {
Harvey Harrison441b62c2008-03-03 16:08:34 -0800457 dbg(1, "%s: device not opened exactly once", __func__);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700458 retval = -ENODEV;
459 goto unlock_exit;
460 }
461 if (dev->udev == NULL) {
462 /* the device was unplugged before the file was released */
Daniel Walker18bcbcf2008-01-11 08:45:44 -0800463
464 /* unlock here as tower_delete frees dev */
465 mutex_unlock(&dev->lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700466 tower_delete (dev);
467 goto exit;
468 }
469
470 /* wait until write transfer is finished */
471 if (dev->interrupt_out_busy) {
472 wait_event_interruptible_timeout (dev->write_wait, !dev->interrupt_out_busy, 2 * HZ);
473 }
474 tower_abort_transfers (dev);
475 dev->open_count = 0;
476
477unlock_exit:
Daniel Walker18bcbcf2008-01-11 08:45:44 -0800478 mutex_unlock(&dev->lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700479
480exit:
Oliver Neukum78663ec2007-10-25 15:48:39 +0200481 mutex_unlock(&open_disc_mutex);
482exit_nolock:
Harvey Harrison441b62c2008-03-03 16:08:34 -0800483 dbg(2, "%s: leave, return value %d", __func__, retval);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700484 return retval;
485}
486
487
488/**
489 * tower_abort_transfers
490 * aborts transfers and frees associated data structures
491 */
492static void tower_abort_transfers (struct lego_usb_tower *dev)
493{
Harvey Harrison441b62c2008-03-03 16:08:34 -0800494 dbg(2, "%s: enter", __func__);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700495
496 if (dev == NULL) {
Harvey Harrison441b62c2008-03-03 16:08:34 -0800497 dbg(1, "%s: dev is null", __func__);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700498 goto exit;
499 }
500
501 /* shutdown transfer */
502 if (dev->interrupt_in_running) {
503 dev->interrupt_in_running = 0;
504 mb();
Mariusz Kozlowskif53510e2006-11-08 15:36:14 +0100505 if (dev->udev)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700506 usb_kill_urb (dev->interrupt_in_urb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700507 }
Mariusz Kozlowskif53510e2006-11-08 15:36:14 +0100508 if (dev->interrupt_out_busy && dev->udev)
509 usb_kill_urb(dev->interrupt_out_urb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700510
511exit:
Harvey Harrison441b62c2008-03-03 16:08:34 -0800512 dbg(2, "%s: leave", __func__);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700513}
514
515
516/**
517 * tower_check_for_read_packet
518 *
519 * To get correct semantics for signals and non-blocking I/O
520 * with packetizing we pretend not to see any data in the read buffer
521 * until it has been there unchanged for at least
522 * dev->packet_timeout_jiffies, or until the buffer is full.
523 */
524static void tower_check_for_read_packet (struct lego_usb_tower *dev)
525{
526 spin_lock_irq (&dev->read_buffer_lock);
527 if (!packet_timeout
528 || time_after(jiffies, dev->read_last_arrival + dev->packet_timeout_jiffies)
529 || dev->read_buffer_length == read_buffer_size) {
530 dev->read_packet_length = dev->read_buffer_length;
531 }
532 dev->interrupt_in_done = 0;
533 spin_unlock_irq (&dev->read_buffer_lock);
534}
535
536
537/**
538 * tower_poll
539 */
540static unsigned int tower_poll (struct file *file, poll_table *wait)
541{
542 struct lego_usb_tower *dev;
543 unsigned int mask = 0;
544
Harvey Harrison441b62c2008-03-03 16:08:34 -0800545 dbg(2, "%s: enter", __func__);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700546
547 dev = file->private_data;
548
549 poll_wait(file, &dev->read_wait, wait);
550 poll_wait(file, &dev->write_wait, wait);
551
552 tower_check_for_read_packet(dev);
553 if (dev->read_packet_length > 0) {
554 mask |= POLLIN | POLLRDNORM;
555 }
556 if (!dev->interrupt_out_busy) {
557 mask |= POLLOUT | POLLWRNORM;
558 }
559
Harvey Harrison441b62c2008-03-03 16:08:34 -0800560 dbg(2, "%s: leave, mask = %d", __func__, mask);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700561
562 return mask;
563}
564
565
566/**
567 * tower_llseek
568 */
569static loff_t tower_llseek (struct file *file, loff_t off, int whence)
570{
571 return -ESPIPE; /* unseekable */
572}
573
574
575/**
576 * tower_read
577 */
578static ssize_t tower_read (struct file *file, char __user *buffer, size_t count, loff_t *ppos)
579{
580 struct lego_usb_tower *dev;
581 size_t bytes_to_read;
582 int i;
583 int retval = 0;
584 unsigned long timeout = 0;
585
Harvey Harrison441b62c2008-03-03 16:08:34 -0800586 dbg(2, "%s: enter, count = %Zd", __func__, count);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700587
588 dev = (struct lego_usb_tower *)file->private_data;
589
590 /* lock this object */
Daniel Walker18bcbcf2008-01-11 08:45:44 -0800591 if (mutex_lock_interruptible(&dev->lock)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700592 retval = -ERESTARTSYS;
593 goto exit;
594 }
595
596 /* verify that the device wasn't unplugged */
597 if (dev->udev == NULL) {
598 retval = -ENODEV;
599 err("No device or device unplugged %d", retval);
600 goto unlock_exit;
601 }
602
603 /* verify that we actually have some data to read */
604 if (count == 0) {
Harvey Harrison441b62c2008-03-03 16:08:34 -0800605 dbg(1, "%s: read request of 0 bytes", __func__);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700606 goto unlock_exit;
607 }
608
609 if (read_timeout) {
610 timeout = jiffies + read_timeout * HZ / 1000;
611 }
612
613 /* wait for data */
614 tower_check_for_read_packet (dev);
615 while (dev->read_packet_length == 0) {
616 if (file->f_flags & O_NONBLOCK) {
617 retval = -EAGAIN;
618 goto unlock_exit;
619 }
620 retval = wait_event_interruptible_timeout(dev->read_wait, dev->interrupt_in_done, dev->packet_timeout_jiffies);
621 if (retval < 0) {
622 goto unlock_exit;
623 }
624
625 /* reset read timeout during read or write activity */
626 if (read_timeout
627 && (dev->read_buffer_length || dev->interrupt_out_busy)) {
628 timeout = jiffies + read_timeout * HZ / 1000;
629 }
630 /* check for read timeout */
631 if (read_timeout && time_after (jiffies, timeout)) {
632 retval = -ETIMEDOUT;
633 goto unlock_exit;
634 }
635 tower_check_for_read_packet (dev);
636 }
637
638 /* copy the data from read_buffer into userspace */
639 bytes_to_read = min(count, dev->read_packet_length);
640
641 if (copy_to_user (buffer, dev->read_buffer, bytes_to_read)) {
642 retval = -EFAULT;
643 goto unlock_exit;
644 }
645
646 spin_lock_irq (&dev->read_buffer_lock);
647 dev->read_buffer_length -= bytes_to_read;
648 dev->read_packet_length -= bytes_to_read;
649 for (i=0; i<dev->read_buffer_length; i++) {
650 dev->read_buffer[i] = dev->read_buffer[i+bytes_to_read];
651 }
652 spin_unlock_irq (&dev->read_buffer_lock);
653
654 retval = bytes_to_read;
655
656unlock_exit:
657 /* unlock the device */
Daniel Walker18bcbcf2008-01-11 08:45:44 -0800658 mutex_unlock(&dev->lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700659
660exit:
Harvey Harrison441b62c2008-03-03 16:08:34 -0800661 dbg(2, "%s: leave, return value %d", __func__, retval);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700662 return retval;
663}
664
665
666/**
667 * tower_write
668 */
669static ssize_t tower_write (struct file *file, const char __user *buffer, size_t count, loff_t *ppos)
670{
671 struct lego_usb_tower *dev;
672 size_t bytes_to_write;
673 int retval = 0;
674
Harvey Harrison441b62c2008-03-03 16:08:34 -0800675 dbg(2, "%s: enter, count = %Zd", __func__, count);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700676
677 dev = (struct lego_usb_tower *)file->private_data;
678
679 /* lock this object */
Daniel Walker18bcbcf2008-01-11 08:45:44 -0800680 if (mutex_lock_interruptible(&dev->lock)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700681 retval = -ERESTARTSYS;
682 goto exit;
683 }
684
685 /* verify that the device wasn't unplugged */
686 if (dev->udev == NULL) {
687 retval = -ENODEV;
688 err("No device or device unplugged %d", retval);
689 goto unlock_exit;
690 }
691
692 /* verify that we actually have some data to write */
693 if (count == 0) {
Harvey Harrison441b62c2008-03-03 16:08:34 -0800694 dbg(1, "%s: write request of 0 bytes", __func__);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700695 goto unlock_exit;
696 }
697
698 /* wait until previous transfer is finished */
699 while (dev->interrupt_out_busy) {
700 if (file->f_flags & O_NONBLOCK) {
701 retval = -EAGAIN;
702 goto unlock_exit;
703 }
704 retval = wait_event_interruptible (dev->write_wait, !dev->interrupt_out_busy);
705 if (retval) {
706 goto unlock_exit;
707 }
708 }
709
710 /* write the data into interrupt_out_buffer from userspace */
711 bytes_to_write = min_t(int, count, write_buffer_size);
Harvey Harrison441b62c2008-03-03 16:08:34 -0800712 dbg(4, "%s: count = %Zd, bytes_to_write = %Zd", __func__, count, bytes_to_write);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700713
714 if (copy_from_user (dev->interrupt_out_buffer, buffer, bytes_to_write)) {
715 retval = -EFAULT;
716 goto unlock_exit;
717 }
718
719 /* send off the urb */
720 usb_fill_int_urb(dev->interrupt_out_urb,
721 dev->udev,
722 usb_sndintpipe(dev->udev, dev->interrupt_out_endpoint->bEndpointAddress),
723 dev->interrupt_out_buffer,
724 bytes_to_write,
725 tower_interrupt_out_callback,
726 dev,
727 dev->interrupt_out_interval);
728
729 dev->interrupt_out_busy = 1;
730 wmb();
731
732 retval = usb_submit_urb (dev->interrupt_out_urb, GFP_KERNEL);
733 if (retval) {
734 dev->interrupt_out_busy = 0;
735 err("Couldn't submit interrupt_out_urb %d", retval);
736 goto unlock_exit;
737 }
738 retval = bytes_to_write;
739
740unlock_exit:
741 /* unlock the device */
Daniel Walker18bcbcf2008-01-11 08:45:44 -0800742 mutex_unlock(&dev->lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700743
744exit:
Harvey Harrison441b62c2008-03-03 16:08:34 -0800745 dbg(2, "%s: leave, return value %d", __func__, retval);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700746
747 return retval;
748}
749
750
751/**
752 * tower_interrupt_in_callback
753 */
David Howells7d12e782006-10-05 14:55:46 +0100754static void tower_interrupt_in_callback (struct urb *urb)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700755{
Ming Leicdc97792008-02-24 18:41:47 +0800756 struct lego_usb_tower *dev = urb->context;
Greg Kroah-Hartman64771a02007-07-18 10:58:02 -0700757 int status = urb->status;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700758 int retval;
759
Harvey Harrison441b62c2008-03-03 16:08:34 -0800760 dbg(4, "%s: enter, status %d", __func__, status);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700761
Harvey Harrison441b62c2008-03-03 16:08:34 -0800762 lego_usb_tower_debug_data(5, __func__, urb->actual_length, urb->transfer_buffer);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700763
Greg Kroah-Hartman64771a02007-07-18 10:58:02 -0700764 if (status) {
765 if (status == -ENOENT ||
766 status == -ECONNRESET ||
767 status == -ESHUTDOWN) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700768 goto exit;
769 } else {
Harvey Harrison441b62c2008-03-03 16:08:34 -0800770 dbg(1, "%s: nonzero status received: %d", __func__, status);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700771 goto resubmit; /* maybe we can recover */
772 }
773 }
774
775 if (urb->actual_length > 0) {
776 spin_lock (&dev->read_buffer_lock);
777 if (dev->read_buffer_length + urb->actual_length < read_buffer_size) {
778 memcpy (dev->read_buffer + dev->read_buffer_length,
779 dev->interrupt_in_buffer,
780 urb->actual_length);
781 dev->read_buffer_length += urb->actual_length;
782 dev->read_last_arrival = jiffies;
Harvey Harrison441b62c2008-03-03 16:08:34 -0800783 dbg(3, "%s: received %d bytes", __func__, urb->actual_length);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700784 } else {
Harvey Harrison441b62c2008-03-03 16:08:34 -0800785 printk(KERN_WARNING "%s: read_buffer overflow, %d bytes dropped", __func__, urb->actual_length);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700786 }
787 spin_unlock (&dev->read_buffer_lock);
788 }
789
790resubmit:
791 /* resubmit if we're still running */
792 if (dev->interrupt_in_running && dev->udev) {
793 retval = usb_submit_urb (dev->interrupt_in_urb, GFP_ATOMIC);
794 if (retval) {
Harvey Harrison441b62c2008-03-03 16:08:34 -0800795 err("%s: usb_submit_urb failed (%d)", __func__, retval);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700796 }
797 }
798
799exit:
800 dev->interrupt_in_done = 1;
801 wake_up_interruptible (&dev->read_wait);
802
Harvey Harrison441b62c2008-03-03 16:08:34 -0800803 lego_usb_tower_debug_data(5, __func__, urb->actual_length, urb->transfer_buffer);
804 dbg(4, "%s: leave, status %d", __func__, status);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700805}
806
807
808/**
809 * tower_interrupt_out_callback
810 */
David Howells7d12e782006-10-05 14:55:46 +0100811static void tower_interrupt_out_callback (struct urb *urb)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700812{
Ming Leicdc97792008-02-24 18:41:47 +0800813 struct lego_usb_tower *dev = urb->context;
Greg Kroah-Hartman64771a02007-07-18 10:58:02 -0700814 int status = urb->status;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700815
Harvey Harrison441b62c2008-03-03 16:08:34 -0800816 dbg(4, "%s: enter, status %d", __func__, status);
817 lego_usb_tower_debug_data(5, __func__, urb->actual_length, urb->transfer_buffer);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700818
819 /* sync/async unlink faults aren't errors */
Greg Kroah-Hartman64771a02007-07-18 10:58:02 -0700820 if (status && !(status == -ENOENT ||
821 status == -ECONNRESET ||
822 status == -ESHUTDOWN)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700823 dbg(1, "%s - nonzero write bulk status received: %d",
Harvey Harrison441b62c2008-03-03 16:08:34 -0800824 __func__, status);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700825 }
826
827 dev->interrupt_out_busy = 0;
828 wake_up_interruptible(&dev->write_wait);
829
Harvey Harrison441b62c2008-03-03 16:08:34 -0800830 lego_usb_tower_debug_data(5, __func__, urb->actual_length, urb->transfer_buffer);
831 dbg(4, "%s: leave, status %d", __func__, status);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700832}
833
834
835/**
836 * tower_probe
837 *
838 * Called by the usb core when a new device is connected that it thinks
839 * this driver might be interested in.
840 */
841static int tower_probe (struct usb_interface *interface, const struct usb_device_id *id)
842{
843 struct usb_device *udev = interface_to_usbdev(interface);
844 struct lego_usb_tower *dev = NULL;
845 struct usb_host_interface *iface_desc;
846 struct usb_endpoint_descriptor* endpoint;
847 struct tower_get_version_reply get_version_reply;
848 int i;
849 int retval = -ENOMEM;
850 int result;
851
Harvey Harrison441b62c2008-03-03 16:08:34 -0800852 dbg(2, "%s: enter", __func__);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700853
Greg Kroah-Hartman1b29a372008-08-18 13:21:04 -0700854 if (udev == NULL)
855 dev_info(&interface->dev, "udev is NULL.\n");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700856
Steven Cole093cf722005-05-03 19:07:24 -0600857 /* allocate memory for our device state and initialize it */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700858
859 dev = kmalloc (sizeof(struct lego_usb_tower), GFP_KERNEL);
860
861 if (dev == NULL) {
862 err ("Out of memory");
863 goto exit;
864 }
865
Daniel Walker18bcbcf2008-01-11 08:45:44 -0800866 mutex_init(&dev->lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700867
868 dev->udev = udev;
869 dev->open_count = 0;
870
871 dev->read_buffer = NULL;
872 dev->read_buffer_length = 0;
873 dev->read_packet_length = 0;
874 spin_lock_init (&dev->read_buffer_lock);
875 dev->packet_timeout_jiffies = packet_timeout * HZ / 1000;
876 dev->read_last_arrival = jiffies;
877
878 init_waitqueue_head (&dev->read_wait);
879 init_waitqueue_head (&dev->write_wait);
880
881 dev->interrupt_in_buffer = NULL;
882 dev->interrupt_in_endpoint = NULL;
883 dev->interrupt_in_urb = NULL;
884 dev->interrupt_in_running = 0;
885 dev->interrupt_in_done = 0;
886
887 dev->interrupt_out_buffer = NULL;
888 dev->interrupt_out_endpoint = NULL;
889 dev->interrupt_out_urb = NULL;
890 dev->interrupt_out_busy = 0;
891
892 iface_desc = interface->cur_altsetting;
893
894 /* set up the endpoint information */
895 for (i = 0; i < iface_desc->desc.bNumEndpoints; ++i) {
896 endpoint = &iface_desc->endpoint[i].desc;
897
Luiz Fernando N. Capitulino240661c2006-10-26 13:02:54 -0300898 if (usb_endpoint_xfer_int(endpoint)) {
899 if (usb_endpoint_dir_in(endpoint))
900 dev->interrupt_in_endpoint = endpoint;
901 else
902 dev->interrupt_out_endpoint = endpoint;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700903 }
904 }
905 if(dev->interrupt_in_endpoint == NULL) {
906 err("interrupt in endpoint not found");
907 goto error;
908 }
909 if (dev->interrupt_out_endpoint == NULL) {
910 err("interrupt out endpoint not found");
911 goto error;
912 }
913
914 dev->read_buffer = kmalloc (read_buffer_size, GFP_KERNEL);
915 if (!dev->read_buffer) {
916 err("Couldn't allocate read_buffer");
917 goto error;
918 }
919 dev->interrupt_in_buffer = kmalloc (le16_to_cpu(dev->interrupt_in_endpoint->wMaxPacketSize), GFP_KERNEL);
920 if (!dev->interrupt_in_buffer) {
921 err("Couldn't allocate interrupt_in_buffer");
922 goto error;
923 }
924 dev->interrupt_in_urb = usb_alloc_urb(0, GFP_KERNEL);
925 if (!dev->interrupt_in_urb) {
926 err("Couldn't allocate interrupt_in_urb");
927 goto error;
928 }
929 dev->interrupt_out_buffer = kmalloc (write_buffer_size, GFP_KERNEL);
930 if (!dev->interrupt_out_buffer) {
931 err("Couldn't allocate interrupt_out_buffer");
932 goto error;
933 }
934 dev->interrupt_out_urb = usb_alloc_urb(0, GFP_KERNEL);
935 if (!dev->interrupt_out_urb) {
936 err("Couldn't allocate interrupt_out_urb");
937 goto error;
938 }
939 dev->interrupt_in_interval = interrupt_in_interval ? interrupt_in_interval : dev->interrupt_in_endpoint->bInterval;
940 dev->interrupt_out_interval = interrupt_out_interval ? interrupt_out_interval : dev->interrupt_out_endpoint->bInterval;
941
942 /* we can register the device now, as it is ready */
943 usb_set_intfdata (interface, dev);
944
945 retval = usb_register_dev (interface, &tower_class);
946
947 if (retval) {
948 /* something prevented us from registering this driver */
949 err ("Not able to get a minor for this device.");
950 usb_set_intfdata (interface, NULL);
951 goto error;
952 }
953 dev->minor = interface->minor;
954
955 /* let the user know what node this device is now attached to */
Greg Kroah-Hartman1b29a372008-08-18 13:21:04 -0700956 dev_info(&interface->dev, "LEGO USB Tower #%d now attached to major "
957 "%d minor %d\n", (dev->minor - LEGO_USB_TOWER_MINOR_BASE),
958 USB_MAJOR, dev->minor);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700959
960 /* get the firmware version and log it */
961 result = usb_control_msg (udev,
962 usb_rcvctrlpipe(udev, 0),
963 LEGO_USB_TOWER_REQUEST_GET_VERSION,
964 USB_TYPE_VENDOR | USB_DIR_IN | USB_RECIP_DEVICE,
965 0,
966 0,
967 &get_version_reply,
968 sizeof(get_version_reply),
969 1000);
970 if (result < 0) {
971 err("LEGO USB Tower get version control request failed");
972 retval = result;
973 goto error;
974 }
Greg Kroah-Hartman1b29a372008-08-18 13:21:04 -0700975 dev_info(&interface->dev, "LEGO USB Tower firmware version is %d.%d "
976 "build %d\n", get_version_reply.major,
977 get_version_reply.minor,
978 le16_to_cpu(get_version_reply.build_no));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700979
980
981exit:
Harvey Harrison441b62c2008-03-03 16:08:34 -0800982 dbg(2, "%s: leave, return value 0x%.8lx (dev)", __func__, (long) dev);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700983
984 return retval;
985
986error:
987 tower_delete(dev);
988 return retval;
989}
990
991
992/**
993 * tower_disconnect
994 *
995 * Called by the usb core when the device is removed from the system.
996 */
997static void tower_disconnect (struct usb_interface *interface)
998{
999 struct lego_usb_tower *dev;
1000 int minor;
1001
Harvey Harrison441b62c2008-03-03 16:08:34 -08001002 dbg(2, "%s: enter", __func__);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001003
Linus Torvalds1da177e2005-04-16 15:20:36 -07001004 dev = usb_get_intfdata (interface);
Oliver Neukum78663ec2007-10-25 15:48:39 +02001005 mutex_lock(&open_disc_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001006 usb_set_intfdata (interface, NULL);
1007
Linus Torvalds1da177e2005-04-16 15:20:36 -07001008 minor = dev->minor;
1009
1010 /* give back our minor */
1011 usb_deregister_dev (interface, &tower_class);
1012
Daniel Walker18bcbcf2008-01-11 08:45:44 -08001013 mutex_lock(&dev->lock);
Oliver Neukum78663ec2007-10-25 15:48:39 +02001014 mutex_unlock(&open_disc_mutex);
Alan Sternd4ead162007-05-22 11:46:41 -04001015
Linus Torvalds1da177e2005-04-16 15:20:36 -07001016 /* if the device is not opened, then we clean up right now */
1017 if (!dev->open_count) {
Daniel Walker18bcbcf2008-01-11 08:45:44 -08001018 mutex_unlock(&dev->lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001019 tower_delete (dev);
1020 } else {
1021 dev->udev = NULL;
Daniel Walker18bcbcf2008-01-11 08:45:44 -08001022 mutex_unlock(&dev->lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001023 }
1024
Greg Kroah-Hartman1b29a372008-08-18 13:21:04 -07001025 dev_info(&interface->dev, "LEGO USB Tower #%d now disconnected\n",
1026 (minor - LEGO_USB_TOWER_MINOR_BASE));
Linus Torvalds1da177e2005-04-16 15:20:36 -07001027
Harvey Harrison441b62c2008-03-03 16:08:34 -08001028 dbg(2, "%s: leave", __func__);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001029}
1030
1031
1032
1033/**
1034 * lego_usb_tower_init
1035 */
1036static int __init lego_usb_tower_init(void)
1037{
1038 int result;
1039 int retval = 0;
1040
Harvey Harrison441b62c2008-03-03 16:08:34 -08001041 dbg(2, "%s: enter", __func__);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001042
1043 /* register this driver with the USB subsystem */
1044 result = usb_register(&tower_driver);
1045 if (result < 0) {
1046 err("usb_register failed for the "__FILE__" driver. Error number %d", result);
1047 retval = -1;
1048 goto exit;
1049 }
1050
Greg Kroah-Hartman1b29a372008-08-18 13:21:04 -07001051 printk(KERN_INFO KBUILD_MODNAME ": " DRIVER_VERSION ":"
1052 DRIVER_DESC "\n");
Linus Torvalds1da177e2005-04-16 15:20:36 -07001053
1054exit:
Harvey Harrison441b62c2008-03-03 16:08:34 -08001055 dbg(2, "%s: leave, return value %d", __func__, retval);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001056
1057 return retval;
1058}
1059
1060
1061/**
1062 * lego_usb_tower_exit
1063 */
1064static void __exit lego_usb_tower_exit(void)
1065{
Harvey Harrison441b62c2008-03-03 16:08:34 -08001066 dbg(2, "%s: enter", __func__);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001067
1068 /* deregister this driver with the USB subsystem */
1069 usb_deregister (&tower_driver);
1070
Harvey Harrison441b62c2008-03-03 16:08:34 -08001071 dbg(2, "%s: leave", __func__);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001072}
1073
1074module_init (lego_usb_tower_init);
1075module_exit (lego_usb_tower_exit);
1076
1077MODULE_AUTHOR(DRIVER_AUTHOR);
1078MODULE_DESCRIPTION(DRIVER_DESC);
1079#ifdef MODULE_LICENSE
1080MODULE_LICENSE("GPL");
1081#endif