USB: BKL removal: legousbtower
[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / drivers / usb / misc / legousbtower.c
blob3d4378fb441083c7032b0b6567efc482407dd76c
1 /*
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)
15 * History:
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
34 * - changed dbg() to use __func__ rather than deprecated __func__
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>
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
52 * - changed back __func__ to __func__
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
91 static int debug = 4;
92 #else
93 static int debug = 0;
94 #endif
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)
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 */
180 __u8 err_code;
181 __u8 spare;
182 } __attribute__ ((packed));
184 struct 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));
194 /* table of devices that work with this driver */
195 static const 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);
201 static DEFINE_MUTEX(open_disc_mutex);
203 #define LEGO_USB_TOWER_MINOR_BASE 160
206 /* Structure to hold all of our device specific stuff */
207 struct lego_usb_tower {
208 struct mutex lock; /* locks this structure */
209 struct usb_device* udev; /* save off the usb device pointer */
210 unsigned char minor; /* the starting minor number for this device */
212 int open_count; /* number of times this port has been opened */
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;
221 wait_queue_head_t read_wait;
222 wait_queue_head_t write_wait;
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;
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;
240 /* local function prototypes */
241 static ssize_t tower_read (struct file *file, char __user *buffer, size_t count, loff_t *ppos);
242 static ssize_t tower_write (struct file *file, const char __user *buffer, size_t count, loff_t *ppos);
243 static inline void tower_delete (struct lego_usb_tower *dev);
244 static int tower_open (struct inode *inode, struct file *file);
245 static int tower_release (struct inode *inode, struct file *file);
246 static unsigned int tower_poll (struct file *file, poll_table *wait);
247 static loff_t tower_llseek (struct file *file, loff_t off, int whence);
249 static void tower_abort_transfers (struct lego_usb_tower *dev);
250 static void tower_check_for_read_packet (struct lego_usb_tower *dev);
251 static void tower_interrupt_in_callback (struct urb *urb);
252 static void tower_interrupt_out_callback (struct urb *urb);
254 static int tower_probe (struct usb_interface *interface, const struct usb_device_id *id);
255 static void tower_disconnect (struct usb_interface *interface);
258 /* file operations needed when we register this driver */
259 static const struct file_operations tower_fops = {
260 .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,
269 static char *legousbtower_devnode(struct device *dev, mode_t *mode)
271 return kasprintf(GFP_KERNEL, "usb/%s", dev_name(dev));
275 * usb class driver info in order to get a minor number from the usb core,
276 * and to have the device registered with the driver core
278 static struct usb_class_driver tower_class = {
279 .name = "legousbtower%d",
280 .devnode = legousbtower_devnode,
281 .fops = &tower_fops,
282 .minor_base = LEGO_USB_TOWER_MINOR_BASE,
286 /* usb specific object needed to register this driver with the usb subsystem */
287 static struct usb_driver tower_driver = {
288 .name = "legousbtower",
289 .probe = tower_probe,
290 .disconnect = tower_disconnect,
291 .id_table = tower_table,
296 * lego_usb_tower_debug_data
298 static inline void lego_usb_tower_debug_data (int level, const char *function, int size, const unsigned char *data)
300 int i;
302 if (debug < level)
303 return;
305 printk (KERN_DEBUG __FILE__": %s - length = %d, data = ", function, size);
306 for (i = 0; i < size; ++i) {
307 printk ("%.2x ", data[i]);
309 printk ("\n");
314 * tower_delete
316 static inline void tower_delete (struct lego_usb_tower *dev)
318 dbg(2, "%s: enter", __func__);
320 tower_abort_transfers (dev);
322 /* free data structures */
323 usb_free_urb(dev->interrupt_in_urb);
324 usb_free_urb(dev->interrupt_out_urb);
325 kfree (dev->read_buffer);
326 kfree (dev->interrupt_in_buffer);
327 kfree (dev->interrupt_out_buffer);
328 kfree (dev);
330 dbg(2, "%s: leave", __func__);
335 * tower_open
337 static int tower_open (struct inode *inode, struct file *file)
339 struct lego_usb_tower *dev = NULL;
340 int subminor;
341 int retval = 0;
342 struct usb_interface *interface;
343 struct tower_reset_reply reset_reply;
344 int result;
346 dbg(2, "%s: enter", __func__);
348 nonseekable_open(inode, file);
349 subminor = iminor(inode);
351 interface = usb_find_interface (&tower_driver, subminor);
353 if (!interface) {
354 err ("%s - error, can't find device for minor %d",
355 __func__, subminor);
356 retval = -ENODEV;
357 goto exit;
360 mutex_lock(&open_disc_mutex);
361 dev = usb_get_intfdata(interface);
363 if (!dev) {
364 mutex_unlock(&open_disc_mutex);
365 retval = -ENODEV;
366 goto exit;
369 /* lock this device */
370 if (mutex_lock_interruptible(&dev->lock)) {
371 mutex_unlock(&open_disc_mutex);
372 retval = -ERESTARTSYS;
373 goto exit;
377 /* allow opening only once */
378 if (dev->open_count) {
379 mutex_unlock(&open_disc_mutex);
380 retval = -EBUSY;
381 goto unlock_exit;
383 dev->open_count = 1;
384 mutex_unlock(&open_disc_mutex);
386 /* reset the tower */
387 result = usb_control_msg (dev->udev,
388 usb_rcvctrlpipe(dev->udev, 0),
389 LEGO_USB_TOWER_REQUEST_RESET,
390 USB_TYPE_VENDOR | USB_DIR_IN | USB_RECIP_DEVICE,
393 &reset_reply,
394 sizeof(reset_reply),
395 1000);
396 if (result < 0) {
397 err("LEGO USB Tower reset control request failed");
398 retval = result;
399 goto unlock_exit;
402 /* initialize in direction */
403 dev->read_buffer_length = 0;
404 dev->read_packet_length = 0;
405 usb_fill_int_urb (dev->interrupt_in_urb,
406 dev->udev,
407 usb_rcvintpipe(dev->udev, dev->interrupt_in_endpoint->bEndpointAddress),
408 dev->interrupt_in_buffer,
409 le16_to_cpu(dev->interrupt_in_endpoint->wMaxPacketSize),
410 tower_interrupt_in_callback,
411 dev,
412 dev->interrupt_in_interval);
414 dev->interrupt_in_running = 1;
415 dev->interrupt_in_done = 0;
416 mb();
418 retval = usb_submit_urb (dev->interrupt_in_urb, GFP_KERNEL);
419 if (retval) {
420 err("Couldn't submit interrupt_in_urb %d", retval);
421 dev->interrupt_in_running = 0;
422 dev->open_count = 0;
423 goto unlock_exit;
426 /* save device in the file's private structure */
427 file->private_data = dev;
429 unlock_exit:
430 mutex_unlock(&dev->lock);
432 exit:
433 dbg(2, "%s: leave, return value %d ", __func__, retval);
435 return retval;
439 * tower_release
441 static int tower_release (struct inode *inode, struct file *file)
443 struct lego_usb_tower *dev;
444 int retval = 0;
446 dbg(2, "%s: enter", __func__);
448 dev = (struct lego_usb_tower *)file->private_data;
450 if (dev == NULL) {
451 dbg(1, "%s: object is NULL", __func__);
452 retval = -ENODEV;
453 goto exit_nolock;
456 mutex_lock(&open_disc_mutex);
457 if (mutex_lock_interruptible(&dev->lock)) {
458 retval = -ERESTARTSYS;
459 goto exit;
462 if (dev->open_count != 1) {
463 dbg(1, "%s: device not opened exactly once", __func__);
464 retval = -ENODEV;
465 goto unlock_exit;
467 if (dev->udev == NULL) {
468 /* the device was unplugged before the file was released */
470 /* unlock here as tower_delete frees dev */
471 mutex_unlock(&dev->lock);
472 tower_delete (dev);
473 goto exit;
476 /* wait until write transfer is finished */
477 if (dev->interrupt_out_busy) {
478 wait_event_interruptible_timeout (dev->write_wait, !dev->interrupt_out_busy, 2 * HZ);
480 tower_abort_transfers (dev);
481 dev->open_count = 0;
483 unlock_exit:
484 mutex_unlock(&dev->lock);
486 exit:
487 mutex_unlock(&open_disc_mutex);
488 exit_nolock:
489 dbg(2, "%s: leave, return value %d", __func__, retval);
490 return retval;
495 * tower_abort_transfers
496 * aborts transfers and frees associated data structures
498 static void tower_abort_transfers (struct lego_usb_tower *dev)
500 dbg(2, "%s: enter", __func__);
502 if (dev == NULL) {
503 dbg(1, "%s: dev is null", __func__);
504 goto exit;
507 /* shutdown transfer */
508 if (dev->interrupt_in_running) {
509 dev->interrupt_in_running = 0;
510 mb();
511 if (dev->udev)
512 usb_kill_urb (dev->interrupt_in_urb);
514 if (dev->interrupt_out_busy && dev->udev)
515 usb_kill_urb(dev->interrupt_out_urb);
517 exit:
518 dbg(2, "%s: leave", __func__);
523 * tower_check_for_read_packet
525 * To get correct semantics for signals and non-blocking I/O
526 * with packetizing we pretend not to see any data in the read buffer
527 * until it has been there unchanged for at least
528 * dev->packet_timeout_jiffies, or until the buffer is full.
530 static void tower_check_for_read_packet (struct lego_usb_tower *dev)
532 spin_lock_irq (&dev->read_buffer_lock);
533 if (!packet_timeout
534 || time_after(jiffies, dev->read_last_arrival + dev->packet_timeout_jiffies)
535 || dev->read_buffer_length == read_buffer_size) {
536 dev->read_packet_length = dev->read_buffer_length;
538 dev->interrupt_in_done = 0;
539 spin_unlock_irq (&dev->read_buffer_lock);
544 * tower_poll
546 static unsigned int tower_poll (struct file *file, poll_table *wait)
548 struct lego_usb_tower *dev;
549 unsigned int mask = 0;
551 dbg(2, "%s: enter", __func__);
553 dev = file->private_data;
555 if (!dev->udev)
556 return POLLERR | POLLHUP;
558 poll_wait(file, &dev->read_wait, wait);
559 poll_wait(file, &dev->write_wait, wait);
561 tower_check_for_read_packet(dev);
562 if (dev->read_packet_length > 0) {
563 mask |= POLLIN | POLLRDNORM;
565 if (!dev->interrupt_out_busy) {
566 mask |= POLLOUT | POLLWRNORM;
569 dbg(2, "%s: leave, mask = %d", __func__, mask);
571 return mask;
576 * tower_llseek
578 static loff_t tower_llseek (struct file *file, loff_t off, int whence)
580 return -ESPIPE; /* unseekable */
585 * tower_read
587 static ssize_t tower_read (struct file *file, char __user *buffer, size_t count, loff_t *ppos)
589 struct lego_usb_tower *dev;
590 size_t bytes_to_read;
591 int i;
592 int retval = 0;
593 unsigned long timeout = 0;
595 dbg(2, "%s: enter, count = %Zd", __func__, count);
597 dev = (struct lego_usb_tower *)file->private_data;
599 /* lock this object */
600 if (mutex_lock_interruptible(&dev->lock)) {
601 retval = -ERESTARTSYS;
602 goto exit;
605 /* verify that the device wasn't unplugged */
606 if (dev->udev == NULL) {
607 retval = -ENODEV;
608 err("No device or device unplugged %d", retval);
609 goto unlock_exit;
612 /* verify that we actually have some data to read */
613 if (count == 0) {
614 dbg(1, "%s: read request of 0 bytes", __func__);
615 goto unlock_exit;
618 if (read_timeout) {
619 timeout = jiffies + read_timeout * HZ / 1000;
622 /* wait for data */
623 tower_check_for_read_packet (dev);
624 while (dev->read_packet_length == 0) {
625 if (file->f_flags & O_NONBLOCK) {
626 retval = -EAGAIN;
627 goto unlock_exit;
629 retval = wait_event_interruptible_timeout(dev->read_wait, dev->interrupt_in_done, dev->packet_timeout_jiffies);
630 if (retval < 0) {
631 goto unlock_exit;
634 /* reset read timeout during read or write activity */
635 if (read_timeout
636 && (dev->read_buffer_length || dev->interrupt_out_busy)) {
637 timeout = jiffies + read_timeout * HZ / 1000;
639 /* check for read timeout */
640 if (read_timeout && time_after (jiffies, timeout)) {
641 retval = -ETIMEDOUT;
642 goto unlock_exit;
644 tower_check_for_read_packet (dev);
647 /* copy the data from read_buffer into userspace */
648 bytes_to_read = min(count, dev->read_packet_length);
650 if (copy_to_user (buffer, dev->read_buffer, bytes_to_read)) {
651 retval = -EFAULT;
652 goto unlock_exit;
655 spin_lock_irq (&dev->read_buffer_lock);
656 dev->read_buffer_length -= bytes_to_read;
657 dev->read_packet_length -= bytes_to_read;
658 for (i=0; i<dev->read_buffer_length; i++) {
659 dev->read_buffer[i] = dev->read_buffer[i+bytes_to_read];
661 spin_unlock_irq (&dev->read_buffer_lock);
663 retval = bytes_to_read;
665 unlock_exit:
666 /* unlock the device */
667 mutex_unlock(&dev->lock);
669 exit:
670 dbg(2, "%s: leave, return value %d", __func__, retval);
671 return retval;
676 * tower_write
678 static ssize_t tower_write (struct file *file, const char __user *buffer, size_t count, loff_t *ppos)
680 struct lego_usb_tower *dev;
681 size_t bytes_to_write;
682 int retval = 0;
684 dbg(2, "%s: enter, count = %Zd", __func__, count);
686 dev = (struct lego_usb_tower *)file->private_data;
688 /* lock this object */
689 if (mutex_lock_interruptible(&dev->lock)) {
690 retval = -ERESTARTSYS;
691 goto exit;
694 /* verify that the device wasn't unplugged */
695 if (dev->udev == NULL) {
696 retval = -ENODEV;
697 err("No device or device unplugged %d", retval);
698 goto unlock_exit;
701 /* verify that we actually have some data to write */
702 if (count == 0) {
703 dbg(1, "%s: write request of 0 bytes", __func__);
704 goto unlock_exit;
707 /* wait until previous transfer is finished */
708 while (dev->interrupt_out_busy) {
709 if (file->f_flags & O_NONBLOCK) {
710 retval = -EAGAIN;
711 goto unlock_exit;
713 retval = wait_event_interruptible (dev->write_wait, !dev->interrupt_out_busy);
714 if (retval) {
715 goto unlock_exit;
719 /* write the data into interrupt_out_buffer from userspace */
720 bytes_to_write = min_t(int, count, write_buffer_size);
721 dbg(4, "%s: count = %Zd, bytes_to_write = %Zd", __func__, count, bytes_to_write);
723 if (copy_from_user (dev->interrupt_out_buffer, buffer, bytes_to_write)) {
724 retval = -EFAULT;
725 goto unlock_exit;
728 /* send off the urb */
729 usb_fill_int_urb(dev->interrupt_out_urb,
730 dev->udev,
731 usb_sndintpipe(dev->udev, dev->interrupt_out_endpoint->bEndpointAddress),
732 dev->interrupt_out_buffer,
733 bytes_to_write,
734 tower_interrupt_out_callback,
735 dev,
736 dev->interrupt_out_interval);
738 dev->interrupt_out_busy = 1;
739 wmb();
741 retval = usb_submit_urb (dev->interrupt_out_urb, GFP_KERNEL);
742 if (retval) {
743 dev->interrupt_out_busy = 0;
744 err("Couldn't submit interrupt_out_urb %d", retval);
745 goto unlock_exit;
747 retval = bytes_to_write;
749 unlock_exit:
750 /* unlock the device */
751 mutex_unlock(&dev->lock);
753 exit:
754 dbg(2, "%s: leave, return value %d", __func__, retval);
756 return retval;
761 * tower_interrupt_in_callback
763 static void tower_interrupt_in_callback (struct urb *urb)
765 struct lego_usb_tower *dev = urb->context;
766 int status = urb->status;
767 int retval;
769 dbg(4, "%s: enter, status %d", __func__, status);
771 lego_usb_tower_debug_data(5, __func__, urb->actual_length, urb->transfer_buffer);
773 if (status) {
774 if (status == -ENOENT ||
775 status == -ECONNRESET ||
776 status == -ESHUTDOWN) {
777 goto exit;
778 } else {
779 dbg(1, "%s: nonzero status received: %d", __func__, status);
780 goto resubmit; /* maybe we can recover */
784 if (urb->actual_length > 0) {
785 spin_lock (&dev->read_buffer_lock);
786 if (dev->read_buffer_length + urb->actual_length < read_buffer_size) {
787 memcpy (dev->read_buffer + dev->read_buffer_length,
788 dev->interrupt_in_buffer,
789 urb->actual_length);
790 dev->read_buffer_length += urb->actual_length;
791 dev->read_last_arrival = jiffies;
792 dbg(3, "%s: received %d bytes", __func__, urb->actual_length);
793 } else {
794 printk(KERN_WARNING "%s: read_buffer overflow, %d bytes dropped", __func__, urb->actual_length);
796 spin_unlock (&dev->read_buffer_lock);
799 resubmit:
800 /* resubmit if we're still running */
801 if (dev->interrupt_in_running && dev->udev) {
802 retval = usb_submit_urb (dev->interrupt_in_urb, GFP_ATOMIC);
803 if (retval) {
804 err("%s: usb_submit_urb failed (%d)", __func__, retval);
808 exit:
809 dev->interrupt_in_done = 1;
810 wake_up_interruptible (&dev->read_wait);
812 lego_usb_tower_debug_data(5, __func__, urb->actual_length, urb->transfer_buffer);
813 dbg(4, "%s: leave, status %d", __func__, status);
818 * tower_interrupt_out_callback
820 static void tower_interrupt_out_callback (struct urb *urb)
822 struct lego_usb_tower *dev = urb->context;
823 int status = urb->status;
825 dbg(4, "%s: enter, status %d", __func__, status);
826 lego_usb_tower_debug_data(5, __func__, urb->actual_length, urb->transfer_buffer);
828 /* sync/async unlink faults aren't errors */
829 if (status && !(status == -ENOENT ||
830 status == -ECONNRESET ||
831 status == -ESHUTDOWN)) {
832 dbg(1, "%s - nonzero write bulk status received: %d",
833 __func__, status);
836 dev->interrupt_out_busy = 0;
837 wake_up_interruptible(&dev->write_wait);
839 lego_usb_tower_debug_data(5, __func__, urb->actual_length, urb->transfer_buffer);
840 dbg(4, "%s: leave, status %d", __func__, status);
845 * tower_probe
847 * Called by the usb core when a new device is connected that it thinks
848 * this driver might be interested in.
850 static int tower_probe (struct usb_interface *interface, const struct usb_device_id *id)
852 struct usb_device *udev = interface_to_usbdev(interface);
853 struct lego_usb_tower *dev = NULL;
854 struct usb_host_interface *iface_desc;
855 struct usb_endpoint_descriptor* endpoint;
856 struct tower_get_version_reply get_version_reply;
857 int i;
858 int retval = -ENOMEM;
859 int result;
861 dbg(2, "%s: enter", __func__);
863 if (udev == NULL)
864 dev_info(&interface->dev, "udev is NULL.\n");
866 /* allocate memory for our device state and initialize it */
868 dev = kmalloc (sizeof(struct lego_usb_tower), GFP_KERNEL);
870 if (dev == NULL) {
871 err ("Out of memory");
872 goto exit;
875 mutex_init(&dev->lock);
877 dev->udev = udev;
878 dev->open_count = 0;
880 dev->read_buffer = NULL;
881 dev->read_buffer_length = 0;
882 dev->read_packet_length = 0;
883 spin_lock_init (&dev->read_buffer_lock);
884 dev->packet_timeout_jiffies = packet_timeout * HZ / 1000;
885 dev->read_last_arrival = jiffies;
887 init_waitqueue_head (&dev->read_wait);
888 init_waitqueue_head (&dev->write_wait);
890 dev->interrupt_in_buffer = NULL;
891 dev->interrupt_in_endpoint = NULL;
892 dev->interrupt_in_urb = NULL;
893 dev->interrupt_in_running = 0;
894 dev->interrupt_in_done = 0;
896 dev->interrupt_out_buffer = NULL;
897 dev->interrupt_out_endpoint = NULL;
898 dev->interrupt_out_urb = NULL;
899 dev->interrupt_out_busy = 0;
901 iface_desc = interface->cur_altsetting;
903 /* set up the endpoint information */
904 for (i = 0; i < iface_desc->desc.bNumEndpoints; ++i) {
905 endpoint = &iface_desc->endpoint[i].desc;
907 if (usb_endpoint_xfer_int(endpoint)) {
908 if (usb_endpoint_dir_in(endpoint))
909 dev->interrupt_in_endpoint = endpoint;
910 else
911 dev->interrupt_out_endpoint = endpoint;
914 if(dev->interrupt_in_endpoint == NULL) {
915 err("interrupt in endpoint not found");
916 goto error;
918 if (dev->interrupt_out_endpoint == NULL) {
919 err("interrupt out endpoint not found");
920 goto error;
923 dev->read_buffer = kmalloc (read_buffer_size, GFP_KERNEL);
924 if (!dev->read_buffer) {
925 err("Couldn't allocate read_buffer");
926 goto error;
928 dev->interrupt_in_buffer = kmalloc (le16_to_cpu(dev->interrupt_in_endpoint->wMaxPacketSize), GFP_KERNEL);
929 if (!dev->interrupt_in_buffer) {
930 err("Couldn't allocate interrupt_in_buffer");
931 goto error;
933 dev->interrupt_in_urb = usb_alloc_urb(0, GFP_KERNEL);
934 if (!dev->interrupt_in_urb) {
935 err("Couldn't allocate interrupt_in_urb");
936 goto error;
938 dev->interrupt_out_buffer = kmalloc (write_buffer_size, GFP_KERNEL);
939 if (!dev->interrupt_out_buffer) {
940 err("Couldn't allocate interrupt_out_buffer");
941 goto error;
943 dev->interrupt_out_urb = usb_alloc_urb(0, GFP_KERNEL);
944 if (!dev->interrupt_out_urb) {
945 err("Couldn't allocate interrupt_out_urb");
946 goto error;
948 dev->interrupt_in_interval = interrupt_in_interval ? interrupt_in_interval : dev->interrupt_in_endpoint->bInterval;
949 dev->interrupt_out_interval = interrupt_out_interval ? interrupt_out_interval : dev->interrupt_out_endpoint->bInterval;
951 /* we can register the device now, as it is ready */
952 usb_set_intfdata (interface, dev);
954 retval = usb_register_dev (interface, &tower_class);
956 if (retval) {
957 /* something prevented us from registering this driver */
958 err ("Not able to get a minor for this device.");
959 usb_set_intfdata (interface, NULL);
960 goto error;
962 dev->minor = interface->minor;
964 /* let the user know what node this device is now attached to */
965 dev_info(&interface->dev, "LEGO USB Tower #%d now attached to major "
966 "%d minor %d\n", (dev->minor - LEGO_USB_TOWER_MINOR_BASE),
967 USB_MAJOR, dev->minor);
969 /* get the firmware version and log it */
970 result = usb_control_msg (udev,
971 usb_rcvctrlpipe(udev, 0),
972 LEGO_USB_TOWER_REQUEST_GET_VERSION,
973 USB_TYPE_VENDOR | USB_DIR_IN | USB_RECIP_DEVICE,
976 &get_version_reply,
977 sizeof(get_version_reply),
978 1000);
979 if (result < 0) {
980 err("LEGO USB Tower get version control request failed");
981 retval = result;
982 goto error;
984 dev_info(&interface->dev, "LEGO USB Tower firmware version is %d.%d "
985 "build %d\n", get_version_reply.major,
986 get_version_reply.minor,
987 le16_to_cpu(get_version_reply.build_no));
990 exit:
991 dbg(2, "%s: leave, return value 0x%.8lx (dev)", __func__, (long) dev);
993 return retval;
995 error:
996 tower_delete(dev);
997 return retval;
1002 * tower_disconnect
1004 * Called by the usb core when the device is removed from the system.
1006 static void tower_disconnect (struct usb_interface *interface)
1008 struct lego_usb_tower *dev;
1009 int minor;
1011 dbg(2, "%s: enter", __func__);
1013 dev = usb_get_intfdata (interface);
1014 mutex_lock(&open_disc_mutex);
1015 usb_set_intfdata (interface, NULL);
1017 minor = dev->minor;
1019 /* give back our minor */
1020 usb_deregister_dev (interface, &tower_class);
1022 mutex_lock(&dev->lock);
1023 mutex_unlock(&open_disc_mutex);
1025 /* if the device is not opened, then we clean up right now */
1026 if (!dev->open_count) {
1027 mutex_unlock(&dev->lock);
1028 tower_delete (dev);
1029 } else {
1030 dev->udev = NULL;
1031 /* wake up pollers */
1032 wake_up_interruptible_all(&dev->read_wait);
1033 wake_up_interruptible_all(&dev->write_wait);
1034 mutex_unlock(&dev->lock);
1037 dev_info(&interface->dev, "LEGO USB Tower #%d now disconnected\n",
1038 (minor - LEGO_USB_TOWER_MINOR_BASE));
1040 dbg(2, "%s: leave", __func__);
1046 * lego_usb_tower_init
1048 static int __init lego_usb_tower_init(void)
1050 int result;
1051 int retval = 0;
1053 dbg(2, "%s: enter", __func__);
1055 /* register this driver with the USB subsystem */
1056 result = usb_register(&tower_driver);
1057 if (result < 0) {
1058 err("usb_register failed for the "__FILE__" driver. Error number %d", result);
1059 retval = -1;
1060 goto exit;
1063 printk(KERN_INFO KBUILD_MODNAME ": " DRIVER_VERSION ":"
1064 DRIVER_DESC "\n");
1066 exit:
1067 dbg(2, "%s: leave, return value %d", __func__, retval);
1069 return retval;
1074 * lego_usb_tower_exit
1076 static void __exit lego_usb_tower_exit(void)
1078 dbg(2, "%s: enter", __func__);
1080 /* deregister this driver with the USB subsystem */
1081 usb_deregister (&tower_driver);
1083 dbg(2, "%s: leave", __func__);
1086 module_init (lego_usb_tower_init);
1087 module_exit (lego_usb_tower_exit);
1089 MODULE_AUTHOR(DRIVER_AUTHOR);
1090 MODULE_DESCRIPTION(DRIVER_DESC);
1091 #ifdef MODULE_LICENSE
1092 MODULE_LICENSE("GPL");
1093 #endif