2 * LEGO USB Tower driver
4 * Copyright (C) 2003 David Glance <davidgsf@sourceforge.net>
5 * 2001-2004 Juergen Stuber <starblue@users.sourceforge.net>
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.
12 * derived from USB Skeleton driver - 0.5
13 * Copyright (C) 2001 Greg Kroah-Hartman (greg@kroah.com)
20 * - simplified buffering, one-shot URBs for writing
22 * - removed IOCTL (setting power/mode is more complicated, postponed)
24 * - added vendor commands for mode of operation and power level in open
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
34 * - changed dbg() to use __func__ rather than deprecated __FUNCTION__
35 * 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>
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
51 * - added nonblocking I/O
52 * - changed back __func__ to __FUNCTION__
53 * - 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
78 #include <linux/kernel.h>
79 #include <linux/errno.h>
80 #include <linux/init.h>
81 #include <linux/slab.h>
82 #include <linux/module.h>
83 #include <linux/completion.h>
84 #include <linux/mutex.h>
85 #include <asm/uaccess.h>
86 #include <linux/usb.h>
87 #include <linux/poll.h>
90 #ifdef CONFIG_USB_DEBUG
96 /* Use our own dbg macro */
98 #define dbg(lvl, format, arg...) do { if (debug >= lvl) printk(KERN_DEBUG __FILE__ ": " format "\n", ## arg); } while (0)
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"
106 /* Module parameters */
107 module_param(debug, int, S_IRUGO | S_IWUSR);
108 MODULE_PARM_DESC(debug, "Debug enabled or not");
110 /* The defaults are chosen to work with the latest versions of leJOS and NQC.
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.
117 static int read_buffer_size = 480;
118 module_param(read_buffer_size, int, 0);
119 MODULE_PARM_DESC(read_buffer_size, "Read buffer size");
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.
127 static int write_buffer_size = 480;
128 module_param(write_buffer_size, int, 0);
129 MODULE_PARM_DESC(write_buffer_size, "Write buffer size");
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.
141 static int packet_timeout = 50;
142 module_param(packet_timeout, int, 0);
143 MODULE_PARM_DESC(packet_timeout, "Packet timeout in ms");
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.
149 static int read_timeout = 200;
150 module_param(read_timeout, int, 0);
151 MODULE_PARM_DESC(read_timeout, "Read timeout in ms");
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.
162 static int interrupt_in_interval = 2;
163 module_param(interrupt_in_interval, int, 0);
164 MODULE_PARM_DESC(interrupt_in_interval, "Interrupt in interval in ms");
166 static int interrupt_out_interval = 8;
167 module_param(interrupt_out_interval, int, 0);
168 MODULE_PARM_DESC(interrupt_out_interval, "Interrupt out interval in ms");
170 /* Define these values to match your device */
171 #define LEGO_USB_TOWER_VENDOR_ID 0x0694
172 #define LEGO_USB_TOWER_PRODUCT_ID 0x0001
174 /* Vendor requests */
175 #define LEGO_USB_TOWER_REQUEST_RESET 0x04
176 #define LEGO_USB_TOWER_REQUEST_GET_VERSION 0xFD
178 struct tower_reset_reply {
179 __le16 size; /* little-endian */
182 } __attribute__ ((packed));
184 struct tower_get_version_reply {
185 __le16 size; /* little-endian */
190 __le16 build_no; /* little-endian */
191 } __attribute__ ((packed));
194 /* table of devices that work with this driver */
195 static struct usb_device_id tower_table [] = {
196 { USB_DEVICE(LEGO_USB_TOWER_VENDOR_ID, LEGO_USB_TOWER_PRODUCT_ID) },
197 { } /* Terminating entry */
200 MODULE_DEVICE_TABLE (usb, tower_table);
202 #define LEGO_USB_TOWER_MINOR_BASE 160
205 /* Structure to hold all of our device specific stuff */
206 struct lego_usb_tower {
207 struct semaphore sem; /* locks this structure */
208 struct usb_device* udev; /* save off the usb device pointer */
209 unsigned char minor; /* the starting minor number for this device */
211 int open_count; /* number of times this port has been opened */
214 size_t read_buffer_length; /* this much came in */
215 size_t read_packet_length; /* this much will be returned on read */
216 spinlock_t read_buffer_lock;
217 int packet_timeout_jiffies;
218 unsigned long read_last_arrival;
220 wait_queue_head_t read_wait;
221 wait_queue_head_t write_wait;
223 char* interrupt_in_buffer;
224 struct usb_endpoint_descriptor* interrupt_in_endpoint;
225 struct urb* interrupt_in_urb;
226 int interrupt_in_interval;
227 int interrupt_in_running;
228 int interrupt_in_done;
230 char* interrupt_out_buffer;
231 struct usb_endpoint_descriptor* interrupt_out_endpoint;
232 struct urb* interrupt_out_urb;
233 int interrupt_out_interval;
234 int interrupt_out_busy;
239 /* local function prototypes */
240 static ssize_t tower_read (struct file *file, char __user *buffer, size_t count, loff_t *ppos);
241 static ssize_t tower_write (struct file *file, const char __user *buffer, size_t count, loff_t *ppos);
242 static inline void tower_delete (struct lego_usb_tower *dev);
243 static int tower_open (struct inode *inode, struct file *file);
244 static int tower_release (struct inode *inode, struct file *file);
245 static unsigned int tower_poll (struct file *file, poll_table *wait);
246 static loff_t tower_llseek (struct file *file, loff_t off, int whence);
248 static void tower_abort_transfers (struct lego_usb_tower *dev);
249 static void tower_check_for_read_packet (struct lego_usb_tower *dev);
250 static void tower_interrupt_in_callback (struct urb *urb);
251 static void tower_interrupt_out_callback (struct urb *urb);
253 static int tower_probe (struct usb_interface *interface, const struct usb_device_id *id);
254 static void tower_disconnect (struct usb_interface *interface);
257 /* prevent races between open() and disconnect */
258 static DEFINE_MUTEX (disconnect_mutex);
260 /* file operations needed when we register this driver */
261 static const struct file_operations tower_fops = {
262 .owner = THIS_MODULE,
264 .write = tower_write,
266 .release = tower_release,
268 .llseek = tower_llseek,
272 * usb class driver info in order to get a minor number from the usb core,
273 * and to have the device registered with the driver core
275 static struct usb_class_driver tower_class = {
276 .name = "legousbtower%d",
278 .minor_base = LEGO_USB_TOWER_MINOR_BASE,
282 /* usb specific object needed to register this driver with the usb subsystem */
283 static struct usb_driver tower_driver = {
284 .name = "legousbtower",
285 .probe = tower_probe,
286 .disconnect = tower_disconnect,
287 .id_table = tower_table,
292 * lego_usb_tower_debug_data
294 static inline void lego_usb_tower_debug_data (int level, const char *function, int size, const unsigned char *data)
301 printk (KERN_DEBUG __FILE__": %s - length = %d, data = ", function, size);
302 for (i = 0; i < size; ++i) {
303 printk ("%.2x ", data[i]);
312 static inline void tower_delete (struct lego_usb_tower *dev)
314 dbg(2, "%s: enter", __FUNCTION__);
316 tower_abort_transfers (dev);
318 /* free data structures */
319 usb_free_urb(dev->interrupt_in_urb);
320 usb_free_urb(dev->interrupt_out_urb);
321 kfree (dev->read_buffer);
322 kfree (dev->interrupt_in_buffer);
323 kfree (dev->interrupt_out_buffer);
326 dbg(2, "%s: leave", __FUNCTION__);
333 static int tower_open (struct inode *inode, struct file *file)
335 struct lego_usb_tower *dev = NULL;
338 struct usb_interface *interface;
339 struct tower_reset_reply reset_reply;
342 dbg(2, "%s: enter", __FUNCTION__);
344 nonseekable_open(inode, file);
345 subminor = iminor(inode);
347 mutex_lock (&disconnect_mutex);
349 interface = usb_find_interface (&tower_driver, subminor);
352 err ("%s - error, can't find device for minor %d",
353 __FUNCTION__, subminor);
355 goto unlock_disconnect_exit;
358 dev = usb_get_intfdata(interface);
362 goto unlock_disconnect_exit;
365 /* lock this device */
366 if (down_interruptible (&dev->sem)) {
367 retval = -ERESTARTSYS;
368 goto unlock_disconnect_exit;
371 /* allow opening only once */
372 if (dev->open_count) {
378 /* reset the tower */
379 result = usb_control_msg (dev->udev,
380 usb_rcvctrlpipe(dev->udev, 0),
381 LEGO_USB_TOWER_REQUEST_RESET,
382 USB_TYPE_VENDOR | USB_DIR_IN | USB_RECIP_DEVICE,
389 err("LEGO USB Tower reset control request failed");
394 /* initialize in direction */
395 dev->read_buffer_length = 0;
396 dev->read_packet_length = 0;
397 usb_fill_int_urb (dev->interrupt_in_urb,
399 usb_rcvintpipe(dev->udev, dev->interrupt_in_endpoint->bEndpointAddress),
400 dev->interrupt_in_buffer,
401 le16_to_cpu(dev->interrupt_in_endpoint->wMaxPacketSize),
402 tower_interrupt_in_callback,
404 dev->interrupt_in_interval);
406 dev->interrupt_in_running = 1;
407 dev->interrupt_in_done = 0;
410 retval = usb_submit_urb (dev->interrupt_in_urb, GFP_KERNEL);
412 err("Couldn't submit interrupt_in_urb %d", retval);
413 dev->interrupt_in_running = 0;
418 /* save device in the file's private structure */
419 file->private_data = dev;
424 unlock_disconnect_exit:
425 mutex_unlock (&disconnect_mutex);
427 dbg(2, "%s: leave, return value %d ", __FUNCTION__, retval);
435 static int tower_release (struct inode *inode, struct file *file)
437 struct lego_usb_tower *dev;
440 dbg(2, "%s: enter", __FUNCTION__);
442 dev = (struct lego_usb_tower *)file->private_data;
445 dbg(1, "%s: object is NULL", __FUNCTION__);
450 if (down_interruptible (&dev->sem)) {
451 retval = -ERESTARTSYS;
455 if (dev->open_count != 1) {
456 dbg(1, "%s: device not opened exactly once", __FUNCTION__);
460 if (dev->udev == NULL) {
461 /* the device was unplugged before the file was released */
462 up (&dev->sem); /* unlock here as tower_delete frees dev */
467 /* wait until write transfer is finished */
468 if (dev->interrupt_out_busy) {
469 wait_event_interruptible_timeout (dev->write_wait, !dev->interrupt_out_busy, 2 * HZ);
471 tower_abort_transfers (dev);
478 dbg(2, "%s: leave, return value %d", __FUNCTION__, retval);
484 * tower_abort_transfers
485 * aborts transfers and frees associated data structures
487 static void tower_abort_transfers (struct lego_usb_tower *dev)
489 dbg(2, "%s: enter", __FUNCTION__);
492 dbg(1, "%s: dev is null", __FUNCTION__);
496 /* shutdown transfer */
497 if (dev->interrupt_in_running) {
498 dev->interrupt_in_running = 0;
501 usb_kill_urb (dev->interrupt_in_urb);
503 if (dev->interrupt_out_busy && dev->udev)
504 usb_kill_urb(dev->interrupt_out_urb);
507 dbg(2, "%s: leave", __FUNCTION__);
512 * tower_check_for_read_packet
514 * To get correct semantics for signals and non-blocking I/O
515 * with packetizing we pretend not to see any data in the read buffer
516 * until it has been there unchanged for at least
517 * dev->packet_timeout_jiffies, or until the buffer is full.
519 static void tower_check_for_read_packet (struct lego_usb_tower *dev)
521 spin_lock_irq (&dev->read_buffer_lock);
523 || time_after(jiffies, dev->read_last_arrival + dev->packet_timeout_jiffies)
524 || dev->read_buffer_length == read_buffer_size) {
525 dev->read_packet_length = dev->read_buffer_length;
527 dev->interrupt_in_done = 0;
528 spin_unlock_irq (&dev->read_buffer_lock);
535 static unsigned int tower_poll (struct file *file, poll_table *wait)
537 struct lego_usb_tower *dev;
538 unsigned int mask = 0;
540 dbg(2, "%s: enter", __FUNCTION__);
542 dev = file->private_data;
544 poll_wait(file, &dev->read_wait, wait);
545 poll_wait(file, &dev->write_wait, wait);
547 tower_check_for_read_packet(dev);
548 if (dev->read_packet_length > 0) {
549 mask |= POLLIN | POLLRDNORM;
551 if (!dev->interrupt_out_busy) {
552 mask |= POLLOUT | POLLWRNORM;
555 dbg(2, "%s: leave, mask = %d", __FUNCTION__, mask);
564 static loff_t tower_llseek (struct file *file, loff_t off, int whence)
566 return -ESPIPE; /* unseekable */
573 static ssize_t tower_read (struct file *file, char __user *buffer, size_t count, loff_t *ppos)
575 struct lego_usb_tower *dev;
576 size_t bytes_to_read;
579 unsigned long timeout = 0;
581 dbg(2, "%s: enter, count = %Zd", __FUNCTION__, count);
583 dev = (struct lego_usb_tower *)file->private_data;
585 /* lock this object */
586 if (down_interruptible (&dev->sem)) {
587 retval = -ERESTARTSYS;
591 /* verify that the device wasn't unplugged */
592 if (dev->udev == NULL) {
594 err("No device or device unplugged %d", retval);
598 /* verify that we actually have some data to read */
600 dbg(1, "%s: read request of 0 bytes", __FUNCTION__);
605 timeout = jiffies + read_timeout * HZ / 1000;
609 tower_check_for_read_packet (dev);
610 while (dev->read_packet_length == 0) {
611 if (file->f_flags & O_NONBLOCK) {
615 retval = wait_event_interruptible_timeout(dev->read_wait, dev->interrupt_in_done, dev->packet_timeout_jiffies);
620 /* reset read timeout during read or write activity */
622 && (dev->read_buffer_length || dev->interrupt_out_busy)) {
623 timeout = jiffies + read_timeout * HZ / 1000;
625 /* check for read timeout */
626 if (read_timeout && time_after (jiffies, timeout)) {
630 tower_check_for_read_packet (dev);
633 /* copy the data from read_buffer into userspace */
634 bytes_to_read = min(count, dev->read_packet_length);
636 if (copy_to_user (buffer, dev->read_buffer, bytes_to_read)) {
641 spin_lock_irq (&dev->read_buffer_lock);
642 dev->read_buffer_length -= bytes_to_read;
643 dev->read_packet_length -= bytes_to_read;
644 for (i=0; i<dev->read_buffer_length; i++) {
645 dev->read_buffer[i] = dev->read_buffer[i+bytes_to_read];
647 spin_unlock_irq (&dev->read_buffer_lock);
649 retval = bytes_to_read;
652 /* unlock the device */
656 dbg(2, "%s: leave, return value %d", __FUNCTION__, retval);
664 static ssize_t tower_write (struct file *file, const char __user *buffer, size_t count, loff_t *ppos)
666 struct lego_usb_tower *dev;
667 size_t bytes_to_write;
670 dbg(2, "%s: enter, count = %Zd", __FUNCTION__, count);
672 dev = (struct lego_usb_tower *)file->private_data;
674 /* lock this object */
675 if (down_interruptible (&dev->sem)) {
676 retval = -ERESTARTSYS;
680 /* verify that the device wasn't unplugged */
681 if (dev->udev == NULL) {
683 err("No device or device unplugged %d", retval);
687 /* verify that we actually have some data to write */
689 dbg(1, "%s: write request of 0 bytes", __FUNCTION__);
693 /* wait until previous transfer is finished */
694 while (dev->interrupt_out_busy) {
695 if (file->f_flags & O_NONBLOCK) {
699 retval = wait_event_interruptible (dev->write_wait, !dev->interrupt_out_busy);
705 /* write the data into interrupt_out_buffer from userspace */
706 bytes_to_write = min_t(int, count, write_buffer_size);
707 dbg(4, "%s: count = %Zd, bytes_to_write = %Zd", __FUNCTION__, count, bytes_to_write);
709 if (copy_from_user (dev->interrupt_out_buffer, buffer, bytes_to_write)) {
714 /* send off the urb */
715 usb_fill_int_urb(dev->interrupt_out_urb,
717 usb_sndintpipe(dev->udev, dev->interrupt_out_endpoint->bEndpointAddress),
718 dev->interrupt_out_buffer,
720 tower_interrupt_out_callback,
722 dev->interrupt_out_interval);
724 dev->interrupt_out_busy = 1;
727 retval = usb_submit_urb (dev->interrupt_out_urb, GFP_KERNEL);
729 dev->interrupt_out_busy = 0;
730 err("Couldn't submit interrupt_out_urb %d", retval);
733 retval = bytes_to_write;
736 /* unlock the device */
740 dbg(2, "%s: leave, return value %d", __FUNCTION__, retval);
747 * tower_interrupt_in_callback
749 static void tower_interrupt_in_callback (struct urb *urb)
751 struct lego_usb_tower *dev = (struct lego_usb_tower *)urb->context;
754 dbg(4, "%s: enter, status %d", __FUNCTION__, urb->status);
756 lego_usb_tower_debug_data(5, __FUNCTION__, urb->actual_length, urb->transfer_buffer);
759 if (urb->status == -ENOENT ||
760 urb->status == -ECONNRESET ||
761 urb->status == -ESHUTDOWN) {
764 dbg(1, "%s: nonzero status received: %d", __FUNCTION__, urb->status);
765 goto resubmit; /* maybe we can recover */
769 if (urb->actual_length > 0) {
770 spin_lock (&dev->read_buffer_lock);
771 if (dev->read_buffer_length + urb->actual_length < read_buffer_size) {
772 memcpy (dev->read_buffer + dev->read_buffer_length,
773 dev->interrupt_in_buffer,
775 dev->read_buffer_length += urb->actual_length;
776 dev->read_last_arrival = jiffies;
777 dbg(3, "%s: received %d bytes", __FUNCTION__, urb->actual_length);
779 printk(KERN_WARNING "%s: read_buffer overflow, %d bytes dropped", __FUNCTION__, urb->actual_length);
781 spin_unlock (&dev->read_buffer_lock);
785 /* resubmit if we're still running */
786 if (dev->interrupt_in_running && dev->udev) {
787 retval = usb_submit_urb (dev->interrupt_in_urb, GFP_ATOMIC);
789 err("%s: usb_submit_urb failed (%d)", __FUNCTION__, retval);
794 dev->interrupt_in_done = 1;
795 wake_up_interruptible (&dev->read_wait);
797 lego_usb_tower_debug_data(5, __FUNCTION__, urb->actual_length, urb->transfer_buffer);
798 dbg(4, "%s: leave, status %d", __FUNCTION__, urb->status);
803 * tower_interrupt_out_callback
805 static void tower_interrupt_out_callback (struct urb *urb)
807 struct lego_usb_tower *dev = (struct lego_usb_tower *)urb->context;
809 dbg(4, "%s: enter, status %d", __FUNCTION__, urb->status);
810 lego_usb_tower_debug_data(5, __FUNCTION__, urb->actual_length, urb->transfer_buffer);
812 /* sync/async unlink faults aren't errors */
813 if (urb->status && !(urb->status == -ENOENT ||
814 urb->status == -ECONNRESET ||
815 urb->status == -ESHUTDOWN)) {
816 dbg(1, "%s - nonzero write bulk status received: %d",
817 __FUNCTION__, urb->status);
820 dev->interrupt_out_busy = 0;
821 wake_up_interruptible(&dev->write_wait);
823 lego_usb_tower_debug_data(5, __FUNCTION__, urb->actual_length, urb->transfer_buffer);
824 dbg(4, "%s: leave, status %d", __FUNCTION__, urb->status);
831 * Called by the usb core when a new device is connected that it thinks
832 * this driver might be interested in.
834 static int tower_probe (struct usb_interface *interface, const struct usb_device_id *id)
836 struct usb_device *udev = interface_to_usbdev(interface);
837 struct lego_usb_tower *dev = NULL;
838 struct usb_host_interface *iface_desc;
839 struct usb_endpoint_descriptor* endpoint;
840 struct tower_get_version_reply get_version_reply;
842 int retval = -ENOMEM;
845 dbg(2, "%s: enter", __FUNCTION__);
848 info ("udev is NULL.");
851 /* allocate memory for our device state and initialize it */
853 dev = kmalloc (sizeof(struct lego_usb_tower), GFP_KERNEL);
856 err ("Out of memory");
860 init_MUTEX (&dev->sem);
865 dev->read_buffer = NULL;
866 dev->read_buffer_length = 0;
867 dev->read_packet_length = 0;
868 spin_lock_init (&dev->read_buffer_lock);
869 dev->packet_timeout_jiffies = packet_timeout * HZ / 1000;
870 dev->read_last_arrival = jiffies;
872 init_waitqueue_head (&dev->read_wait);
873 init_waitqueue_head (&dev->write_wait);
875 dev->interrupt_in_buffer = NULL;
876 dev->interrupt_in_endpoint = NULL;
877 dev->interrupt_in_urb = NULL;
878 dev->interrupt_in_running = 0;
879 dev->interrupt_in_done = 0;
881 dev->interrupt_out_buffer = NULL;
882 dev->interrupt_out_endpoint = NULL;
883 dev->interrupt_out_urb = NULL;
884 dev->interrupt_out_busy = 0;
886 iface_desc = interface->cur_altsetting;
888 /* set up the endpoint information */
889 for (i = 0; i < iface_desc->desc.bNumEndpoints; ++i) {
890 endpoint = &iface_desc->endpoint[i].desc;
892 if (usb_endpoint_xfer_int(endpoint)) {
893 if (usb_endpoint_dir_in(endpoint))
894 dev->interrupt_in_endpoint = endpoint;
896 dev->interrupt_out_endpoint = endpoint;
899 if(dev->interrupt_in_endpoint == NULL) {
900 err("interrupt in endpoint not found");
903 if (dev->interrupt_out_endpoint == NULL) {
904 err("interrupt out endpoint not found");
908 dev->read_buffer = kmalloc (read_buffer_size, GFP_KERNEL);
909 if (!dev->read_buffer) {
910 err("Couldn't allocate read_buffer");
913 dev->interrupt_in_buffer = kmalloc (le16_to_cpu(dev->interrupt_in_endpoint->wMaxPacketSize), GFP_KERNEL);
914 if (!dev->interrupt_in_buffer) {
915 err("Couldn't allocate interrupt_in_buffer");
918 dev->interrupt_in_urb = usb_alloc_urb(0, GFP_KERNEL);
919 if (!dev->interrupt_in_urb) {
920 err("Couldn't allocate interrupt_in_urb");
923 dev->interrupt_out_buffer = kmalloc (write_buffer_size, GFP_KERNEL);
924 if (!dev->interrupt_out_buffer) {
925 err("Couldn't allocate interrupt_out_buffer");
928 dev->interrupt_out_urb = usb_alloc_urb(0, GFP_KERNEL);
929 if (!dev->interrupt_out_urb) {
930 err("Couldn't allocate interrupt_out_urb");
933 dev->interrupt_in_interval = interrupt_in_interval ? interrupt_in_interval : dev->interrupt_in_endpoint->bInterval;
934 dev->interrupt_out_interval = interrupt_out_interval ? interrupt_out_interval : dev->interrupt_out_endpoint->bInterval;
936 /* we can register the device now, as it is ready */
937 usb_set_intfdata (interface, dev);
939 retval = usb_register_dev (interface, &tower_class);
942 /* something prevented us from registering this driver */
943 err ("Not able to get a minor for this device.");
944 usb_set_intfdata (interface, NULL);
947 dev->minor = interface->minor;
949 /* let the user know what node this device is now attached to */
950 info ("LEGO USB Tower #%d now attached to major %d minor %d", (dev->minor - LEGO_USB_TOWER_MINOR_BASE), USB_MAJOR, dev->minor);
952 /* get the firmware version and log it */
953 result = usb_control_msg (udev,
954 usb_rcvctrlpipe(udev, 0),
955 LEGO_USB_TOWER_REQUEST_GET_VERSION,
956 USB_TYPE_VENDOR | USB_DIR_IN | USB_RECIP_DEVICE,
960 sizeof(get_version_reply),
963 err("LEGO USB Tower get version control request failed");
967 info("LEGO USB Tower firmware version is %d.%d build %d",
968 get_version_reply.major,
969 get_version_reply.minor,
970 le16_to_cpu(get_version_reply.build_no));
974 dbg(2, "%s: leave, return value 0x%.8lx (dev)", __FUNCTION__, (long) dev);
987 * Called by the usb core when the device is removed from the system.
989 static void tower_disconnect (struct usb_interface *interface)
991 struct lego_usb_tower *dev;
994 dbg(2, "%s: enter", __FUNCTION__);
996 mutex_lock (&disconnect_mutex);
998 dev = usb_get_intfdata (interface);
999 usb_set_intfdata (interface, NULL);
1006 /* give back our minor */
1007 usb_deregister_dev (interface, &tower_class);
1009 /* if the device is not opened, then we clean up right now */
1010 if (!dev->open_count) {
1018 mutex_unlock (&disconnect_mutex);
1020 info("LEGO USB Tower #%d now disconnected", (minor - LEGO_USB_TOWER_MINOR_BASE));
1022 dbg(2, "%s: leave", __FUNCTION__);
1028 * lego_usb_tower_init
1030 static int __init lego_usb_tower_init(void)
1035 dbg(2, "%s: enter", __FUNCTION__);
1037 /* register this driver with the USB subsystem */
1038 result = usb_register(&tower_driver);
1040 err("usb_register failed for the "__FILE__" driver. Error number %d", result);
1045 info(DRIVER_DESC " " DRIVER_VERSION);
1048 dbg(2, "%s: leave, return value %d", __FUNCTION__, retval);
1055 * lego_usb_tower_exit
1057 static void __exit lego_usb_tower_exit(void)
1059 dbg(2, "%s: enter", __FUNCTION__);
1061 /* deregister this driver with the USB subsystem */
1062 usb_deregister (&tower_driver);
1064 dbg(2, "%s: leave", __FUNCTION__);
1067 module_init (lego_usb_tower_init);
1068 module_exit (lego_usb_tower_exit);
1070 MODULE_AUTHOR(DRIVER_AUTHOR);
1071 MODULE_DESCRIPTION(DRIVER_DESC);
1072 #ifdef MODULE_LICENSE
1073 MODULE_LICENSE("GPL");