Merge branch 'for-linus' of master.kernel.org:/pub/scm/linux/kernel/git/roland/infiniband
[linux-2.6] / drivers / usb / misc / adutux.c
1 /*
2  * adutux - driver for ADU devices from Ontrak Control Systems
3  * This is an experimental driver. Use at your own risk.
4  * This driver is not supported by Ontrak Control Systems.
5  *
6  * Copyright (c) 2003 John Homppi (SCO, leave this notice here)
7  *
8  * This program is free software; you can redistribute it and/or
9  * modify it under the terms of the GNU General Public License as
10  * published by the Free Software Foundation; either version 2 of
11  * the License, or (at your option) any later version.
12  *
13  * derived from the Lego USB Tower driver 0.56:
14  * Copyright (c) 2003 David Glance <davidgsf@sourceforge.net>
15  *               2001 Juergen Stuber <stuber@loria.fr>
16  * that was derived from USB Skeleton driver - 0.5
17  * Copyright (c) 2001 Greg Kroah-Hartman (greg@kroah.com)
18  *
19  */
20
21 #include <linux/kernel.h>
22 #include <linux/errno.h>
23 #include <linux/init.h>
24 #include <linux/slab.h>
25 #include <linux/module.h>
26 #include <linux/usb.h>
27 #include <asm/uaccess.h>
28
29 #ifdef CONFIG_USB_DEBUG
30 static int debug = 5;
31 #else
32 static int debug = 1;
33 #endif
34
35 /* Use our own dbg macro */
36 #undef dbg
37 #define dbg(lvl, format, arg...)                                        \
38 do {                                                                    \
39         if (debug >= lvl)                                               \
40                 printk(KERN_DEBUG __FILE__ " : " format " \n", ## arg); \
41 } while (0)
42
43
44 /* Version Information */
45 #define DRIVER_VERSION "v0.0.13"
46 #define DRIVER_AUTHOR "John Homppi"
47 #define DRIVER_DESC "adutux (see www.ontrak.net)"
48
49 /* Module parameters */
50 module_param(debug, int, S_IRUGO | S_IWUSR);
51 MODULE_PARM_DESC(debug, "Debug enabled or not");
52
53 /* Define these values to match your device */
54 #define ADU_VENDOR_ID 0x0a07
55 #define ADU_PRODUCT_ID 0x0064
56
57 /* table of devices that work with this driver */
58 static struct usb_device_id device_table [] = {
59         { USB_DEVICE(ADU_VENDOR_ID, ADU_PRODUCT_ID) },          /* ADU100 */
60         { USB_DEVICE(ADU_VENDOR_ID, ADU_PRODUCT_ID+20) },       /* ADU120 */
61         { USB_DEVICE(ADU_VENDOR_ID, ADU_PRODUCT_ID+30) },       /* ADU130 */
62         { USB_DEVICE(ADU_VENDOR_ID, ADU_PRODUCT_ID+100) },      /* ADU200 */
63         { USB_DEVICE(ADU_VENDOR_ID, ADU_PRODUCT_ID+108) },      /* ADU208 */
64         { USB_DEVICE(ADU_VENDOR_ID, ADU_PRODUCT_ID+118) },      /* ADU218 */
65         { }/* Terminating entry */
66 };
67
68 MODULE_DEVICE_TABLE(usb, device_table);
69
70 #ifdef CONFIG_USB_DYNAMIC_MINORS
71 #define ADU_MINOR_BASE  0
72 #else
73 #define ADU_MINOR_BASE  67
74 #endif
75
76 /* we can have up to this number of device plugged in at once */
77 #define MAX_DEVICES     16
78
79 #define COMMAND_TIMEOUT (2*HZ)  /* 60 second timeout for a command */
80
81 /* Structure to hold all of our device specific stuff */
82 struct adu_device {
83         struct semaphore        sem; /* locks this structure */
84         struct usb_device*      udev; /* save off the usb device pointer */
85         struct usb_interface*   interface;
86         unsigned char           minor; /* the starting minor number for this device */
87         char                    serial_number[8];
88
89         int                     open_count; /* number of times this port has been opened */
90
91         char*                   read_buffer_primary;
92         int                     read_buffer_length;
93         char*                   read_buffer_secondary;
94         int                     secondary_head;
95         int                     secondary_tail;
96         spinlock_t              buflock;
97
98         wait_queue_head_t       read_wait;
99         wait_queue_head_t       write_wait;
100
101         char*                   interrupt_in_buffer;
102         struct usb_endpoint_descriptor* interrupt_in_endpoint;
103         struct urb*             interrupt_in_urb;
104         int                     read_urb_finished;
105
106         char*                   interrupt_out_buffer;
107         struct usb_endpoint_descriptor* interrupt_out_endpoint;
108         struct urb*             interrupt_out_urb;
109 };
110
111 /* prevent races between open() and disconnect */
112 static DEFINE_MUTEX(disconnect_mutex);
113 static struct usb_driver adu_driver;
114
115 static void adu_debug_data(int level, const char *function, int size,
116                            const unsigned char *data)
117 {
118         int i;
119
120         if (debug < level)
121                 return;
122
123         printk(KERN_DEBUG __FILE__": %s - length = %d, data = ",
124                function, size);
125         for (i = 0; i < size; ++i)
126                 printk("%.2x ", data[i]);
127         printk("\n");
128 }
129
130 /**
131  * adu_abort_transfers
132  *      aborts transfers and frees associated data structures
133  */
134 static void adu_abort_transfers(struct adu_device *dev)
135 {
136         dbg(2," %s : enter", __FUNCTION__);
137
138         if (dev == NULL) {
139                 dbg(1," %s : dev is null", __FUNCTION__);
140                 goto exit;
141         }
142
143         if (dev->udev == NULL) {
144                 dbg(1," %s : udev is null", __FUNCTION__);
145                 goto exit;
146         }
147
148         dbg(2," %s : udev state %d", __FUNCTION__, dev->udev->state);
149         if (dev->udev->state == USB_STATE_NOTATTACHED) {
150                 dbg(1," %s : udev is not attached", __FUNCTION__);
151                 goto exit;
152         }
153
154         /* shutdown transfer */
155         usb_unlink_urb(dev->interrupt_in_urb);
156         usb_unlink_urb(dev->interrupt_out_urb);
157
158 exit:
159         dbg(2," %s : leave", __FUNCTION__);
160 }
161
162 static void adu_delete(struct adu_device *dev)
163 {
164         dbg(2, "%s enter", __FUNCTION__);
165
166         adu_abort_transfers(dev);
167
168         /* free data structures */
169         usb_free_urb(dev->interrupt_in_urb);
170         usb_free_urb(dev->interrupt_out_urb);
171         kfree(dev->read_buffer_primary);
172         kfree(dev->read_buffer_secondary);
173         kfree(dev->interrupt_in_buffer);
174         kfree(dev->interrupt_out_buffer);
175         kfree(dev);
176
177         dbg(2, "%s : leave", __FUNCTION__);
178 }
179
180 static void adu_interrupt_in_callback(struct urb *urb)
181 {
182         struct adu_device *dev = urb->context;
183
184         dbg(4," %s : enter, status %d", __FUNCTION__, urb->status);
185         adu_debug_data(5, __FUNCTION__, urb->actual_length,
186                        urb->transfer_buffer);
187
188         spin_lock(&dev->buflock);
189
190         if (urb->status != 0) {
191                 if ((urb->status != -ENOENT) && (urb->status != -ECONNRESET)) {
192                         dbg(1," %s : nonzero status received: %d",
193                             __FUNCTION__, urb->status);
194                 }
195                 goto exit;
196         }
197
198         if (urb->actual_length > 0 && dev->interrupt_in_buffer[0] != 0x00) {
199                 if (dev->read_buffer_length <
200                     (4 * le16_to_cpu(dev->interrupt_in_endpoint->wMaxPacketSize)) -
201                      (urb->actual_length)) {
202                         memcpy (dev->read_buffer_primary +
203                                 dev->read_buffer_length,
204                                 dev->interrupt_in_buffer, urb->actual_length);
205
206                         dev->read_buffer_length += urb->actual_length;
207                         dbg(2," %s reading  %d ", __FUNCTION__,
208                             urb->actual_length);
209                 } else {
210                         dbg(1," %s : read_buffer overflow", __FUNCTION__);
211                 }
212         }
213
214 exit:
215         dev->read_urb_finished = 1;
216         spin_unlock(&dev->buflock);
217         /* always wake up so we recover from errors */
218         wake_up_interruptible(&dev->read_wait);
219         adu_debug_data(5, __FUNCTION__, urb->actual_length,
220                        urb->transfer_buffer);
221         dbg(4," %s : leave, status %d", __FUNCTION__, urb->status);
222 }
223
224 static void adu_interrupt_out_callback(struct urb *urb)
225 {
226         struct adu_device *dev = urb->context;
227
228         dbg(4," %s : enter, status %d", __FUNCTION__, urb->status);
229         adu_debug_data(5,__FUNCTION__, urb->actual_length, urb->transfer_buffer);
230
231         if (urb->status != 0) {
232                 if ((urb->status != -ENOENT) &&
233                     (urb->status != -ECONNRESET)) {
234                         dbg(1, " %s :nonzero status received: %d",
235                             __FUNCTION__, urb->status);
236                 }
237                 goto exit;
238         }
239
240         wake_up_interruptible(&dev->write_wait);
241 exit:
242
243         adu_debug_data(5, __FUNCTION__, urb->actual_length,
244                        urb->transfer_buffer);
245         dbg(4," %s : leave, status %d", __FUNCTION__, urb->status);
246 }
247
248 static int adu_open(struct inode *inode, struct file *file)
249 {
250         struct adu_device *dev = NULL;
251         struct usb_interface *interface;
252         int subminor;
253         int retval = 0;
254
255         dbg(2,"%s : enter", __FUNCTION__);
256
257         subminor = iminor(inode);
258
259         mutex_lock(&disconnect_mutex);
260
261         interface = usb_find_interface(&adu_driver, subminor);
262         if (!interface) {
263                 err("%s - error, can't find device for minor %d",
264                     __FUNCTION__, subminor);
265                 retval = -ENODEV;
266                 goto exit_no_device;
267         }
268
269         dev = usb_get_intfdata(interface);
270         if (!dev) {
271                 retval = -ENODEV;
272                 goto exit_no_device;
273         }
274
275         /* lock this device */
276         if ((retval = down_interruptible(&dev->sem))) {
277                 dbg(2, "%s : sem down failed", __FUNCTION__);
278                 goto exit_no_device;
279         }
280
281         /* increment our usage count for the device */
282         ++dev->open_count;
283         dbg(2,"%s : open count %d", __FUNCTION__, dev->open_count);
284
285         /* save device in the file's private structure */
286         file->private_data = dev;
287
288         if (dev->open_count == 1) {
289                 /* initialize in direction */
290                 dev->read_buffer_length = 0;
291
292                 /* fixup first read by having urb waiting for it */
293                 usb_fill_int_urb(dev->interrupt_in_urb,dev->udev,
294                                  usb_rcvintpipe(dev->udev,
295                                                 dev->interrupt_in_endpoint->bEndpointAddress),
296                                  dev->interrupt_in_buffer,
297                                  le16_to_cpu(dev->interrupt_in_endpoint->wMaxPacketSize),
298                                  adu_interrupt_in_callback, dev,
299                                  dev->interrupt_in_endpoint->bInterval);
300                 /* dev->interrupt_in_urb->transfer_flags |= URB_ASYNC_UNLINK; */
301                 dev->read_urb_finished = 0;
302                 retval = usb_submit_urb(dev->interrupt_in_urb, GFP_KERNEL);
303                 if (retval)
304                         --dev->open_count;
305         }
306         up(&dev->sem);
307
308 exit_no_device:
309         mutex_unlock(&disconnect_mutex);
310         dbg(2,"%s : leave, return value %d ", __FUNCTION__, retval);
311
312         return retval;
313 }
314
315 static int adu_release_internal(struct adu_device *dev)
316 {
317         int retval = 0;
318
319         dbg(2," %s : enter", __FUNCTION__);
320
321         if (dev->udev == NULL) {
322                 /* the device was unplugged before the file was released */
323                 adu_delete(dev);
324                 goto exit;
325         }
326
327         /* decrement our usage count for the device */
328         --dev->open_count;
329         dbg(2," %s : open count %d", __FUNCTION__, dev->open_count);
330         if (dev->open_count <= 0) {
331                 adu_abort_transfers(dev);
332                 dev->open_count = 0;
333         }
334
335 exit:
336         dbg(2," %s : leave", __FUNCTION__);
337         return retval;
338 }
339
340 static int adu_release(struct inode *inode, struct file *file)
341 {
342         struct adu_device *dev = NULL;
343         int retval = 0;
344
345         dbg(2," %s : enter", __FUNCTION__);
346
347         if (file == NULL) {
348                 dbg(1," %s : file is NULL", __FUNCTION__);
349                 retval = -ENODEV;
350                 goto exit;
351         }
352
353         dev = file->private_data;
354
355         if (dev == NULL) {
356                 dbg(1," %s : object is NULL", __FUNCTION__);
357                 retval = -ENODEV;
358                 goto exit;
359         }
360
361         /* lock our device */
362         down(&dev->sem); /* not interruptible */
363
364         if (dev->open_count <= 0) {
365                 dbg(1," %s : device not opened", __FUNCTION__);
366                 retval = -ENODEV;
367                 goto exit;
368         }
369
370         /* do the work */
371         retval = adu_release_internal(dev);
372
373 exit:
374         if (dev)
375                 up(&dev->sem);
376         dbg(2," %s : leave, return value %d", __FUNCTION__, retval);
377         return retval;
378 }
379
380 static ssize_t adu_read(struct file *file, __user char *buffer, size_t count,
381                         loff_t *ppos)
382 {
383         struct adu_device *dev;
384         size_t bytes_read = 0;
385         size_t bytes_to_read = count;
386         int i;
387         int retval = 0;
388         int timeout = 0;
389         int should_submit = 0;
390         unsigned long flags;
391         DECLARE_WAITQUEUE(wait, current);
392
393         dbg(2," %s : enter, count = %Zd, file=%p", __FUNCTION__, count, file);
394
395         dev = file->private_data;
396         dbg(2," %s : dev=%p", __FUNCTION__, dev);
397         /* lock this object */
398         if (down_interruptible(&dev->sem))
399                 return -ERESTARTSYS;
400
401         /* verify that the device wasn't unplugged */
402         if (dev->udev == NULL || dev->minor == 0) {
403                 retval = -ENODEV;
404                 err("No device or device unplugged %d", retval);
405                 goto exit;
406         }
407
408         /* verify that some data was requested */
409         if (count == 0) {
410                 dbg(1," %s : read request of 0 bytes", __FUNCTION__);
411                 goto exit;
412         }
413
414         timeout = COMMAND_TIMEOUT;
415         dbg(2," %s : about to start looping", __FUNCTION__);
416         while (bytes_to_read) {
417                 int data_in_secondary = dev->secondary_tail - dev->secondary_head;
418                 dbg(2," %s : while, data_in_secondary=%d, status=%d",
419                     __FUNCTION__, data_in_secondary,
420                     dev->interrupt_in_urb->status);
421
422                 if (data_in_secondary) {
423                         /* drain secondary buffer */
424                         int amount = bytes_to_read < data_in_secondary ? bytes_to_read : data_in_secondary;
425                         i = copy_to_user(buffer, dev->read_buffer_secondary+dev->secondary_head, amount);
426                         if (i < 0) {
427                                 retval = -EFAULT;
428                                 goto exit;
429                         }
430                         dev->secondary_head += (amount - i);
431                         bytes_read += (amount - i);
432                         bytes_to_read -= (amount - i);
433                         if (i) {
434                                 retval = bytes_read ? bytes_read : -EFAULT;
435                                 goto exit;
436                         }
437                 } else {
438                         /* we check the primary buffer */
439                         spin_lock_irqsave (&dev->buflock, flags);
440                         if (dev->read_buffer_length) {
441                                 /* we secure access to the primary */
442                                 char *tmp;
443                                 dbg(2," %s : swap, read_buffer_length = %d",
444                                     __FUNCTION__, dev->read_buffer_length);
445                                 tmp = dev->read_buffer_secondary;
446                                 dev->read_buffer_secondary = dev->read_buffer_primary;
447                                 dev->read_buffer_primary = tmp;
448                                 dev->secondary_head = 0;
449                                 dev->secondary_tail = dev->read_buffer_length;
450                                 dev->read_buffer_length = 0;
451                                 spin_unlock_irqrestore(&dev->buflock, flags);
452                                 /* we have a free buffer so use it */
453                                 should_submit = 1;
454                         } else {
455                                 /* even the primary was empty - we may need to do IO */
456                                 if (dev->interrupt_in_urb->status == -EINPROGRESS) {
457                                         /* somebody is doing IO */
458                                         spin_unlock_irqrestore(&dev->buflock, flags);
459                                         dbg(2," %s : submitted already", __FUNCTION__);
460                                 } else {
461                                         /* we must initiate input */
462                                         dbg(2," %s : initiate input", __FUNCTION__);
463                                         dev->read_urb_finished = 0;
464
465                                         usb_fill_int_urb(dev->interrupt_in_urb,dev->udev,
466                                                          usb_rcvintpipe(dev->udev,
467                                                                         dev->interrupt_in_endpoint->bEndpointAddress),
468                                                          dev->interrupt_in_buffer,
469                                                          le16_to_cpu(dev->interrupt_in_endpoint->wMaxPacketSize),
470                                                          adu_interrupt_in_callback,
471                                                          dev,
472                                                          dev->interrupt_in_endpoint->bInterval);
473                                         retval = usb_submit_urb(dev->interrupt_in_urb, GFP_ATOMIC);
474                                         if (!retval) {
475                                                 spin_unlock_irqrestore(&dev->buflock, flags);
476                                                 dbg(2," %s : submitted OK", __FUNCTION__);
477                                         } else {
478                                                 if (retval == -ENOMEM) {
479                                                         retval = bytes_read ? bytes_read : -ENOMEM;
480                                                 }
481                                                 spin_unlock_irqrestore(&dev->buflock, flags);
482                                                 dbg(2," %s : submit failed", __FUNCTION__);
483                                                 goto exit;
484                                         }
485                                 }
486
487                                 /* we wait for I/O to complete */
488                                 set_current_state(TASK_INTERRUPTIBLE);
489                                 add_wait_queue(&dev->read_wait, &wait);
490                                 if (!dev->read_urb_finished)
491                                         timeout = schedule_timeout(COMMAND_TIMEOUT);
492                                 else
493                                         set_current_state(TASK_RUNNING);
494                                 remove_wait_queue(&dev->read_wait, &wait);
495
496                                 if (timeout <= 0) {
497                                         dbg(2," %s : timeout", __FUNCTION__);
498                                         retval = bytes_read ? bytes_read : -ETIMEDOUT;
499                                         goto exit;
500                                 }
501
502                                 if (signal_pending(current)) {
503                                         dbg(2," %s : signal pending", __FUNCTION__);
504                                         retval = bytes_read ? bytes_read : -EINTR;
505                                         goto exit;
506                                 }
507                         }
508                 }
509         }
510
511         retval = bytes_read;
512         /* if the primary buffer is empty then use it */
513         if (should_submit && !dev->interrupt_in_urb->status==-EINPROGRESS) {
514                 usb_fill_int_urb(dev->interrupt_in_urb,dev->udev,
515                                  usb_rcvintpipe(dev->udev,
516                                                 dev->interrupt_in_endpoint->bEndpointAddress),
517                                                 dev->interrupt_in_buffer,
518                                                 le16_to_cpu(dev->interrupt_in_endpoint->wMaxPacketSize),
519                                                 adu_interrupt_in_callback,
520                                                 dev,
521                                                 dev->interrupt_in_endpoint->bInterval);
522                 /* dev->interrupt_in_urb->transfer_flags |= URB_ASYNC_UNLINK; */
523                 dev->read_urb_finished = 0;
524                 usb_submit_urb(dev->interrupt_in_urb, GFP_KERNEL);
525                 /* we ignore failure */
526         }
527
528 exit:
529         /* unlock the device */
530         up(&dev->sem);
531
532         dbg(2," %s : leave, return value %d", __FUNCTION__, retval);
533         return retval;
534 }
535
536 static ssize_t adu_write(struct file *file, const __user char *buffer,
537                          size_t count, loff_t *ppos)
538 {
539         struct adu_device *dev;
540         size_t bytes_written = 0;
541         size_t bytes_to_write;
542         size_t buffer_size;
543         int retval;
544         int timeout = 0;
545
546         dbg(2," %s : enter, count = %Zd", __FUNCTION__, count);
547
548         dev = file->private_data;
549
550         /* lock this object */
551         retval = down_interruptible(&dev->sem);
552         if (retval)
553                 goto exit_nolock;
554
555         /* verify that the device wasn't unplugged */
556         if (dev->udev == NULL || dev->minor == 0) {
557                 retval = -ENODEV;
558                 err("No device or device unplugged %d", retval);
559                 goto exit;
560         }
561
562         /* verify that we actually have some data to write */
563         if (count == 0) {
564                 dbg(1," %s : write request of 0 bytes", __FUNCTION__);
565                 goto exit;
566         }
567
568
569         while (count > 0) {
570                 if (dev->interrupt_out_urb->status == -EINPROGRESS) {
571                         timeout = COMMAND_TIMEOUT;
572
573                         while (timeout > 0) {
574                                 if (signal_pending(current)) {
575                                 dbg(1," %s : interrupted", __FUNCTION__);
576                                 retval = -EINTR;
577                                 goto exit;
578                         }
579                         up(&dev->sem);
580                         timeout = interruptible_sleep_on_timeout(&dev->write_wait, timeout);
581                         retval = down_interruptible(&dev->sem);
582                         if (retval) {
583                                 retval = bytes_written ? bytes_written : retval;
584                                 goto exit_nolock;
585                         }
586                         if (timeout > 0) {
587                                 break;
588                         }
589                         dbg(1," %s : interrupted timeout: %d", __FUNCTION__, timeout);
590                 }
591
592
593                 dbg(1," %s : final timeout: %d", __FUNCTION__, timeout);
594
595                 if (timeout == 0) {
596                         dbg(1, "%s - command timed out.", __FUNCTION__);
597                         retval = -ETIMEDOUT;
598                         goto exit;
599                 }
600
601                 dbg(4," %s : in progress, count = %Zd", __FUNCTION__, count);
602
603                 } else {
604                         dbg(4," %s : sending, count = %Zd", __FUNCTION__, count);
605
606                         /* write the data into interrupt_out_buffer from userspace */
607                         buffer_size = le16_to_cpu(dev->interrupt_out_endpoint->wMaxPacketSize);
608                         bytes_to_write = count > buffer_size ? buffer_size : count;
609                         dbg(4," %s : buffer_size = %Zd, count = %Zd, bytes_to_write = %Zd",
610                             __FUNCTION__, buffer_size, count, bytes_to_write);
611
612                         if (copy_from_user(dev->interrupt_out_buffer, buffer, bytes_to_write) != 0) {
613                                 retval = -EFAULT;
614                                 goto exit;
615                         }
616
617                         /* send off the urb */
618                         usb_fill_int_urb(
619                                 dev->interrupt_out_urb,
620                                 dev->udev,
621                                 usb_sndintpipe(dev->udev, dev->interrupt_out_endpoint->bEndpointAddress),
622                                 dev->interrupt_out_buffer,
623                                 bytes_to_write,
624                                 adu_interrupt_out_callback,
625                                 dev,
626                                 dev->interrupt_in_endpoint->bInterval);
627                         /* dev->interrupt_in_urb->transfer_flags |= URB_ASYNC_UNLINK; */
628                         dev->interrupt_out_urb->actual_length = bytes_to_write;
629                         retval = usb_submit_urb(dev->interrupt_out_urb, GFP_KERNEL);
630                         if (retval < 0) {
631                                 err("Couldn't submit interrupt_out_urb %d", retval);
632                                 goto exit;
633                         }
634
635                         buffer += bytes_to_write;
636                         count -= bytes_to_write;
637
638                         bytes_written += bytes_to_write;
639                 }
640         }
641
642         retval = bytes_written;
643
644 exit:
645         /* unlock the device */
646         up(&dev->sem);
647 exit_nolock:
648
649         dbg(2," %s : leave, return value %d", __FUNCTION__, retval);
650
651         return retval;
652 }
653
654 /* file operations needed when we register this driver */
655 static const struct file_operations adu_fops = {
656         .owner = THIS_MODULE,
657         .read  = adu_read,
658         .write = adu_write,
659         .open = adu_open,
660         .release = adu_release,
661 };
662
663 /*
664  * usb class driver info in order to get a minor number from the usb core,
665  * and to have the device registered with devfs and the driver core
666  */
667 static struct usb_class_driver adu_class = {
668         .name = "usb/adutux%d",
669         .fops = &adu_fops,
670         .minor_base = ADU_MINOR_BASE,
671 };
672
673 /**
674  * adu_probe
675  *
676  * Called by the usb core when a new device is connected that it thinks
677  * this driver might be interested in.
678  */
679 static int adu_probe(struct usb_interface *interface,
680                      const struct usb_device_id *id)
681 {
682         struct usb_device *udev = interface_to_usbdev(interface);
683         struct adu_device *dev = NULL;
684         struct usb_host_interface *iface_desc;
685         struct usb_endpoint_descriptor *endpoint;
686         int retval = -ENODEV;
687         int in_end_size;
688         int out_end_size;
689         int i;
690
691         dbg(2," %s : enter", __FUNCTION__);
692
693         if (udev == NULL) {
694                 dev_err(&interface->dev, "udev is NULL.\n");
695                 goto exit;
696         }
697
698         /* allocate memory for our device state and intialize it */
699         dev = kzalloc(sizeof(struct adu_device), GFP_KERNEL);
700         if (dev == NULL) {
701                 dev_err(&interface->dev, "Out of memory\n");
702                 retval = -ENOMEM;
703                 goto exit;
704         }
705
706         init_MUTEX(&dev->sem);
707         spin_lock_init(&dev->buflock);
708         dev->udev = udev;
709         init_waitqueue_head(&dev->read_wait);
710         init_waitqueue_head(&dev->write_wait);
711
712         iface_desc = &interface->altsetting[0];
713
714         /* set up the endpoint information */
715         for (i = 0; i < iface_desc->desc.bNumEndpoints; ++i) {
716                 endpoint = &iface_desc->endpoint[i].desc;
717
718                 if (usb_endpoint_is_int_in(endpoint))
719                         dev->interrupt_in_endpoint = endpoint;
720
721                 if (usb_endpoint_is_int_out(endpoint))
722                         dev->interrupt_out_endpoint = endpoint;
723         }
724         if (dev->interrupt_in_endpoint == NULL) {
725                 dev_err(&interface->dev, "interrupt in endpoint not found\n");
726                 goto error;
727         }
728         if (dev->interrupt_out_endpoint == NULL) {
729                 dev_err(&interface->dev, "interrupt out endpoint not found\n");
730                 goto error;
731         }
732
733         in_end_size = le16_to_cpu(dev->interrupt_in_endpoint->wMaxPacketSize);
734         out_end_size = le16_to_cpu(dev->interrupt_out_endpoint->wMaxPacketSize);
735
736         dev->read_buffer_primary = kmalloc((4 * in_end_size), GFP_KERNEL);
737         if (!dev->read_buffer_primary) {
738                 dev_err(&interface->dev, "Couldn't allocate read_buffer_primary\n");
739                 retval = -ENOMEM;
740                 goto error;
741         }
742
743         /* debug code prime the buffer */
744         memset(dev->read_buffer_primary, 'a', in_end_size);
745         memset(dev->read_buffer_primary + in_end_size, 'b', in_end_size);
746         memset(dev->read_buffer_primary + (2 * in_end_size), 'c', in_end_size);
747         memset(dev->read_buffer_primary + (3 * in_end_size), 'd', in_end_size);
748
749         dev->read_buffer_secondary = kmalloc((4 * in_end_size), GFP_KERNEL);
750         if (!dev->read_buffer_secondary) {
751                 dev_err(&interface->dev, "Couldn't allocate read_buffer_secondary\n");
752                 retval = -ENOMEM;
753                 goto error;
754         }
755
756         /* debug code prime the buffer */
757         memset(dev->read_buffer_secondary, 'e', in_end_size);
758         memset(dev->read_buffer_secondary + in_end_size, 'f', in_end_size);
759         memset(dev->read_buffer_secondary + (2 * in_end_size), 'g', in_end_size);
760         memset(dev->read_buffer_secondary + (3 * in_end_size), 'h', in_end_size);
761
762         dev->interrupt_in_buffer = kmalloc(in_end_size, GFP_KERNEL);
763         if (!dev->interrupt_in_buffer) {
764                 dev_err(&interface->dev, "Couldn't allocate interrupt_in_buffer\n");
765                 goto error;
766         }
767
768         /* debug code prime the buffer */
769         memset(dev->interrupt_in_buffer, 'i', in_end_size);
770
771         dev->interrupt_in_urb = usb_alloc_urb(0, GFP_KERNEL);
772         if (!dev->interrupt_in_urb) {
773                 dev_err(&interface->dev, "Couldn't allocate interrupt_in_urb\n");
774                 goto error;
775         }
776         dev->interrupt_out_buffer = kmalloc(out_end_size, GFP_KERNEL);
777         if (!dev->interrupt_out_buffer) {
778                 dev_err(&interface->dev, "Couldn't allocate interrupt_out_buffer\n");
779                 goto error;
780         }
781         dev->interrupt_out_urb = usb_alloc_urb(0, GFP_KERNEL);
782         if (!dev->interrupt_out_urb) {
783                 dev_err(&interface->dev, "Couldn't allocate interrupt_out_urb\n");
784                 goto error;
785         }
786
787         if (!usb_string(udev, udev->descriptor.iSerialNumber, dev->serial_number,
788                         sizeof(dev->serial_number))) {
789                 dev_err(&interface->dev, "Could not retrieve serial number\n");
790                 goto error;
791         }
792         dbg(2," %s : serial_number=%s", __FUNCTION__, dev->serial_number);
793
794         /* we can register the device now, as it is ready */
795         usb_set_intfdata(interface, dev);
796
797         retval = usb_register_dev(interface, &adu_class);
798
799         if (retval) {
800                 /* something prevented us from registering this driver */
801                 dev_err(&interface->dev, "Not able to get a minor for this device.\n");
802                 usb_set_intfdata(interface, NULL);
803                 goto error;
804         }
805
806         dev->minor = interface->minor;
807
808         /* let the user know what node this device is now attached to */
809         dev_info(&interface->dev, "ADU%d %s now attached to /dev/usb/adutux%d",
810                  udev->descriptor.idProduct, dev->serial_number,
811                  (dev->minor - ADU_MINOR_BASE));
812 exit:
813         dbg(2," %s : leave, return value %p (dev)", __FUNCTION__, dev);
814
815         return retval;
816
817 error:
818         adu_delete(dev);
819         return retval;
820 }
821
822 /**
823  * adu_disconnect
824  *
825  * Called by the usb core when the device is removed from the system.
826  */
827 static void adu_disconnect(struct usb_interface *interface)
828 {
829         struct adu_device *dev;
830         int minor;
831
832         dbg(2," %s : enter", __FUNCTION__);
833
834         mutex_lock(&disconnect_mutex); /* not interruptible */
835
836         dev = usb_get_intfdata(interface);
837         usb_set_intfdata(interface, NULL);
838
839         down(&dev->sem); /* not interruptible */
840
841         minor = dev->minor;
842
843         /* give back our minor */
844         usb_deregister_dev(interface, &adu_class);
845         dev->minor = 0;
846
847         /* if the device is not opened, then we clean up right now */
848         dbg(2," %s : open count %d", __FUNCTION__, dev->open_count);
849         if (!dev->open_count) {
850                 up(&dev->sem);
851                 adu_delete(dev);
852         } else {
853                 dev->udev = NULL;
854                 up(&dev->sem);
855         }
856
857         mutex_unlock(&disconnect_mutex);
858
859         dev_info(&interface->dev, "ADU device adutux%d now disconnected",
860                  (minor - ADU_MINOR_BASE));
861
862         dbg(2," %s : leave", __FUNCTION__);
863 }
864
865 /* usb specific object needed to register this driver with the usb subsystem */
866 static struct usb_driver adu_driver = {
867         .name = "adutux",
868         .probe = adu_probe,
869         .disconnect = adu_disconnect,
870         .id_table = device_table,
871 };
872
873 static int __init adu_init(void)
874 {
875         int result;
876
877         dbg(2," %s : enter", __FUNCTION__);
878
879         /* register this driver with the USB subsystem */
880         result = usb_register(&adu_driver);
881         if (result < 0) {
882                 err("usb_register failed for the "__FILE__" driver. "
883                     "Error number %d", result);
884                 goto exit;
885         }
886
887         info("adutux " DRIVER_DESC " " DRIVER_VERSION);
888         info("adutux is an experimental driver. Use at your own risk");
889
890 exit:
891         dbg(2," %s : leave, return value %d", __FUNCTION__, result);
892
893         return result;
894 }
895
896 static void __exit adu_exit(void)
897 {
898         dbg(2," %s : enter", __FUNCTION__);
899         /* deregister this driver with the USB subsystem */
900         usb_deregister(&adu_driver);
901         dbg(2," %s : leave", __FUNCTION__);
902 }
903
904 module_init(adu_init);
905 module_exit(adu_exit);
906
907 MODULE_AUTHOR(DRIVER_AUTHOR);
908 MODULE_DESCRIPTION(DRIVER_DESC);
909 MODULE_LICENSE("GPL");