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spi-topcliff-pch: add recovery processing in case wait-event timeout
[zen-stable.git] / drivers / usb / misc / adutux.c
blob284b85461410a82129ed43d7082953d8cb81849e
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 <linux/mutex.h>
28 #include <asm/uaccess.h>
29
30 #ifdef CONFIG_USB_DEBUG
31 static int debug = 5;
32 #else
33 static int debug = 1;
34 #endif
35
36 /* Use our own dbg macro */
37 #undef dbg
38 #define dbg(lvl, format, arg...) \
39 do { \
40 if (debug >= lvl) \
41 printk(KERN_DEBUG "%s: " format "\n", __FILE__, ##arg); \
42 } while (0)
43
44
45 /* Version Information */
46 #define DRIVER_VERSION "v0.0.13"
47 #define DRIVER_AUTHOR "John Homppi"
48 #define DRIVER_DESC "adutux (see www.ontrak.net)"
49
50 /* Module parameters */
51 module_param(debug, int, S_IRUGO | S_IWUSR);
52 MODULE_PARM_DESC(debug, "Debug enabled or not");
53
54 /* Define these values to match your device */
55 #define ADU_VENDOR_ID 0x0a07
56 #define ADU_PRODUCT_ID 0x0064
57
58 /* table of devices that work with this driver */
59 static const struct usb_device_id device_table[] = {
60 { USB_DEVICE(ADU_VENDOR_ID, ADU_PRODUCT_ID) }, /* ADU100 */
61 { USB_DEVICE(ADU_VENDOR_ID, ADU_PRODUCT_ID+20) }, /* ADU120 */
62 { USB_DEVICE(ADU_VENDOR_ID, ADU_PRODUCT_ID+30) }, /* ADU130 */
63 { USB_DEVICE(ADU_VENDOR_ID, ADU_PRODUCT_ID+100) }, /* ADU200 */
64 { USB_DEVICE(ADU_VENDOR_ID, ADU_PRODUCT_ID+108) }, /* ADU208 */
65 { USB_DEVICE(ADU_VENDOR_ID, ADU_PRODUCT_ID+118) }, /* ADU218 */
66 { }/* Terminating entry */
67 };
68
69 MODULE_DEVICE_TABLE(usb, device_table);
70
71 #ifdef CONFIG_USB_DYNAMIC_MINORS
72 #define ADU_MINOR_BASE 0
73 #else
74 #define ADU_MINOR_BASE 67
75 #endif
76
77 /* we can have up to this number of device plugged in at once */
78 #define MAX_DEVICES 16
79
80 #define COMMAND_TIMEOUT (2*HZ) /* 60 second timeout for a command */
81
82 /*
83 * The locking scheme is a vanilla 3-lock:
84 * adu_device.buflock: A spinlock, covers what IRQs touch.
85 * adutux_mutex: A Static lock to cover open_count. It would also cover
86 * any globals, but we don't have them in 2.6.
87 * adu_device.mtx: A mutex to hold across sleepers like copy_from_user.
88 * It covers all of adu_device, except the open_count
89 * and what .buflock covers.
90 */
91
92 /* Structure to hold all of our device specific stuff */
93 struct adu_device {
94 struct mutex mtx;
95 struct usb_device* udev; /* save off the usb device pointer */
96 struct usb_interface* interface;
97 unsigned int minor; /* the starting minor number for this device */
98 char serial_number[8];
99
100 int open_count; /* number of times this port has been opened */
101
102 char* read_buffer_primary;
103 int read_buffer_length;
104 char* read_buffer_secondary;
105 int secondary_head;
106 int secondary_tail;
107 spinlock_t buflock;
108
109 wait_queue_head_t read_wait;
110 wait_queue_head_t write_wait;
111
112 char* interrupt_in_buffer;
113 struct usb_endpoint_descriptor* interrupt_in_endpoint;
114 struct urb* interrupt_in_urb;
115 int read_urb_finished;
116
117 char* interrupt_out_buffer;
118 struct usb_endpoint_descriptor* interrupt_out_endpoint;
119 struct urb* interrupt_out_urb;
120 int out_urb_finished;
121 };
122
123 static DEFINE_MUTEX(adutux_mutex);
124
125 static struct usb_driver adu_driver;
126
127 static void adu_debug_data(int level, const char *function, int size,
128 const unsigned char *data)
129 {
130 int i;
131
132 if (debug < level)
133 return;
134
135 printk(KERN_DEBUG "%s: %s - length = %d, data = ",
136 __FILE__, function, size);
137 for (i = 0; i < size; ++i)
138 printk("%.2x ", data[i]);
139 printk("\n");
140 }
141
142 /**
143 * adu_abort_transfers
144 * aborts transfers and frees associated data structures
145 */
146 static void adu_abort_transfers(struct adu_device *dev)
147 {
148 unsigned long flags;
149
150 dbg(2," %s : enter", __func__);
151
152 if (dev->udev == NULL) {
153 dbg(1," %s : udev is null", __func__);
154 goto exit;
155 }
156
157 /* shutdown transfer */
158
159 /* XXX Anchor these instead */
160 spin_lock_irqsave(&dev->buflock, flags);
161 if (!dev->read_urb_finished) {
162 spin_unlock_irqrestore(&dev->buflock, flags);
163 usb_kill_urb(dev->interrupt_in_urb);
164 } else
165 spin_unlock_irqrestore(&dev->buflock, flags);
166
167 spin_lock_irqsave(&dev->buflock, flags);
168 if (!dev->out_urb_finished) {
169 spin_unlock_irqrestore(&dev->buflock, flags);
170 usb_kill_urb(dev->interrupt_out_urb);
171 } else
172 spin_unlock_irqrestore(&dev->buflock, flags);
173
174 exit:
175 dbg(2," %s : leave", __func__);
176 }
177
178 static void adu_delete(struct adu_device *dev)
179 {
180 dbg(2, "%s enter", __func__);
181
182 /* free data structures */
183 usb_free_urb(dev->interrupt_in_urb);
184 usb_free_urb(dev->interrupt_out_urb);
185 kfree(dev->read_buffer_primary);
186 kfree(dev->read_buffer_secondary);
187 kfree(dev->interrupt_in_buffer);
188 kfree(dev->interrupt_out_buffer);
189 kfree(dev);
190
191 dbg(2, "%s : leave", __func__);
192 }
193
194 static void adu_interrupt_in_callback(struct urb *urb)
195 {
196 struct adu_device *dev = urb->context;
197 int status = urb->status;
198
199 dbg(4," %s : enter, status %d", __func__, status);
200 adu_debug_data(5, __func__, urb->actual_length,
201 urb->transfer_buffer);
202
203 spin_lock(&dev->buflock);
204
205 if (status != 0) {
206 if ((status != -ENOENT) && (status != -ECONNRESET) &&
207 (status != -ESHUTDOWN)) {
208 dbg(1," %s : nonzero status received: %d",
209 __func__, status);
210 }
211 goto exit;
212 }
213
214 if (urb->actual_length > 0 && dev->interrupt_in_buffer[0] != 0x00) {
215 if (dev->read_buffer_length <
216 (4 * usb_endpoint_maxp(dev->interrupt_in_endpoint)) -
217 (urb->actual_length)) {
218 memcpy (dev->read_buffer_primary +
219 dev->read_buffer_length,
220 dev->interrupt_in_buffer, urb->actual_length);
221
222 dev->read_buffer_length += urb->actual_length;
223 dbg(2," %s reading %d ", __func__,
224 urb->actual_length);
225 } else {
226 dbg(1," %s : read_buffer overflow", __func__);
227 }
228 }
229
230 exit:
231 dev->read_urb_finished = 1;
232 spin_unlock(&dev->buflock);
233 /* always wake up so we recover from errors */
234 wake_up_interruptible(&dev->read_wait);
235 adu_debug_data(5, __func__, urb->actual_length,
236 urb->transfer_buffer);
237 dbg(4," %s : leave, status %d", __func__, status);
238 }
239
240 static void adu_interrupt_out_callback(struct urb *urb)
241 {
242 struct adu_device *dev = urb->context;
243 int status = urb->status;
244
245 dbg(4," %s : enter, status %d", __func__, status);
246 adu_debug_data(5,__func__, urb->actual_length, urb->transfer_buffer);
247
248 if (status != 0) {
249 if ((status != -ENOENT) &&
250 (status != -ECONNRESET)) {
251 dbg(1, " %s :nonzero status received: %d",
252 __func__, status);
253 }
254 goto exit;
255 }
256
257 spin_lock(&dev->buflock);
258 dev->out_urb_finished = 1;
259 wake_up(&dev->write_wait);
260 spin_unlock(&dev->buflock);
261 exit:
262
263 adu_debug_data(5, __func__, urb->actual_length,
264 urb->transfer_buffer);
265 dbg(4," %s : leave, status %d", __func__, status);
266 }
267
268 static int adu_open(struct inode *inode, struct file *file)
269 {
270 struct adu_device *dev = NULL;
271 struct usb_interface *interface;
272 int subminor;
273 int retval;
274
275 dbg(2,"%s : enter", __func__);
276
277 subminor = iminor(inode);
278
279 if ((retval = mutex_lock_interruptible(&adutux_mutex))) {
280 dbg(2, "%s : mutex lock failed", __func__);
281 goto exit_no_lock;
282 }
283
284 interface = usb_find_interface(&adu_driver, subminor);
285 if (!interface) {
286 printk(KERN_ERR "adutux: %s - error, can't find device for "
287 "minor %d\n", __func__, subminor);
288 retval = -ENODEV;
289 goto exit_no_device;
290 }
291
292 dev = usb_get_intfdata(interface);
293 if (!dev || !dev->udev) {
294 retval = -ENODEV;
295 goto exit_no_device;
296 }
297
298 /* check that nobody else is using the device */
299 if (dev->open_count) {
300 retval = -EBUSY;
301 goto exit_no_device;
302 }
303
304 ++dev->open_count;
305 dbg(2,"%s : open count %d", __func__, dev->open_count);
306
307 /* save device in the file's private structure */
308 file->private_data = dev;
309
310 /* initialize in direction */
311 dev->read_buffer_length = 0;
312
313 /* fixup first read by having urb waiting for it */
314 usb_fill_int_urb(dev->interrupt_in_urb,dev->udev,
315 usb_rcvintpipe(dev->udev,
316 dev->interrupt_in_endpoint->bEndpointAddress),
317 dev->interrupt_in_buffer,
318 usb_endpoint_maxp(dev->interrupt_in_endpoint),
319 adu_interrupt_in_callback, dev,
320 dev->interrupt_in_endpoint->bInterval);
321 dev->read_urb_finished = 0;
322 if (usb_submit_urb(dev->interrupt_in_urb, GFP_KERNEL))
323 dev->read_urb_finished = 1;
324 /* we ignore failure */
325 /* end of fixup for first read */
326
327 /* initialize out direction */
328 dev->out_urb_finished = 1;
329
330 retval = 0;
331
332 exit_no_device:
333 mutex_unlock(&adutux_mutex);
334 exit_no_lock:
335 dbg(2,"%s : leave, return value %d ", __func__, retval);
336 return retval;
337 }
338
339 static void adu_release_internal(struct adu_device *dev)
340 {
341 dbg(2," %s : enter", __func__);
342
343 /* decrement our usage count for the device */
344 --dev->open_count;
345 dbg(2," %s : open count %d", __func__, dev->open_count);
346 if (dev->open_count <= 0) {
347 adu_abort_transfers(dev);
348 dev->open_count = 0;
349 }
350
351 dbg(2," %s : leave", __func__);
352 }
353
354 static int adu_release(struct inode *inode, struct file *file)
355 {
356 struct adu_device *dev;
357 int retval = 0;
358
359 dbg(2," %s : enter", __func__);
360
361 if (file == NULL) {
362 dbg(1," %s : file is NULL", __func__);
363 retval = -ENODEV;
364 goto exit;
365 }
366
367 dev = file->private_data;
368 if (dev == NULL) {
369 dbg(1," %s : object is NULL", __func__);
370 retval = -ENODEV;
371 goto exit;
372 }
373
374 mutex_lock(&adutux_mutex); /* not interruptible */
375
376 if (dev->open_count <= 0) {
377 dbg(1," %s : device not opened", __func__);
378 retval = -ENODEV;
379 goto unlock;
380 }
381
382 adu_release_internal(dev);
383 if (dev->udev == NULL) {
384 /* the device was unplugged before the file was released */
385 if (!dev->open_count) /* ... and we're the last user */
386 adu_delete(dev);
387 }
388 unlock:
389 mutex_unlock(&adutux_mutex);
390 exit:
391 dbg(2," %s : leave, return value %d", __func__, retval);
392 return retval;
393 }
394
395 static ssize_t adu_read(struct file *file, __user char *buffer, size_t count,
396 loff_t *ppos)
397 {
398 struct adu_device *dev;
399 size_t bytes_read = 0;
400 size_t bytes_to_read = count;
401 int i;
402 int retval = 0;
403 int timeout = 0;
404 int should_submit = 0;
405 unsigned long flags;
406 DECLARE_WAITQUEUE(wait, current);
407
408 dbg(2," %s : enter, count = %Zd, file=%p", __func__, count, file);
409
410 dev = file->private_data;
411 dbg(2," %s : dev=%p", __func__, dev);
412
413 if (mutex_lock_interruptible(&dev->mtx))
414 return -ERESTARTSYS;
415
416 /* verify that the device wasn't unplugged */
417 if (dev->udev == NULL) {
418 retval = -ENODEV;
419 printk(KERN_ERR "adutux: No device or device unplugged %d\n",
420 retval);
421 goto exit;
422 }
423
424 /* verify that some data was requested */
425 if (count == 0) {
426 dbg(1," %s : read request of 0 bytes", __func__);
427 goto exit;
428 }
429
430 timeout = COMMAND_TIMEOUT;
431 dbg(2," %s : about to start looping", __func__);
432 while (bytes_to_read) {
433 int data_in_secondary = dev->secondary_tail - dev->secondary_head;
434 dbg(2," %s : while, data_in_secondary=%d, status=%d",
435 __func__, data_in_secondary,
436 dev->interrupt_in_urb->status);
437
438 if (data_in_secondary) {
439 /* drain secondary buffer */
440 int amount = bytes_to_read < data_in_secondary ? bytes_to_read : data_in_secondary;
441 i = copy_to_user(buffer, dev->read_buffer_secondary+dev->secondary_head, amount);
442 if (i) {
443 retval = -EFAULT;
444 goto exit;
445 }
446 dev->secondary_head += (amount - i);
447 bytes_read += (amount - i);
448 bytes_to_read -= (amount - i);
449 if (i) {
450 retval = bytes_read ? bytes_read : -EFAULT;
451 goto exit;
452 }
453 } else {
454 /* we check the primary buffer */
455 spin_lock_irqsave (&dev->buflock, flags);
456 if (dev->read_buffer_length) {
457 /* we secure access to the primary */
458 char *tmp;
459 dbg(2," %s : swap, read_buffer_length = %d",
460 __func__, dev->read_buffer_length);
461 tmp = dev->read_buffer_secondary;
462 dev->read_buffer_secondary = dev->read_buffer_primary;
463 dev->read_buffer_primary = tmp;
464 dev->secondary_head = 0;
465 dev->secondary_tail = dev->read_buffer_length;
466 dev->read_buffer_length = 0;
467 spin_unlock_irqrestore(&dev->buflock, flags);
468 /* we have a free buffer so use it */
469 should_submit = 1;
470 } else {
471 /* even the primary was empty - we may need to do IO */
472 if (!dev->read_urb_finished) {
473 /* somebody is doing IO */
474 spin_unlock_irqrestore(&dev->buflock, flags);
475 dbg(2," %s : submitted already", __func__);
476 } else {
477 /* we must initiate input */
478 dbg(2," %s : initiate input", __func__);
479 dev->read_urb_finished = 0;
480 spin_unlock_irqrestore(&dev->buflock, flags);
481
482 usb_fill_int_urb(dev->interrupt_in_urb,dev->udev,
483 usb_rcvintpipe(dev->udev,
484 dev->interrupt_in_endpoint->bEndpointAddress),
485 dev->interrupt_in_buffer,
486 usb_endpoint_maxp(dev->interrupt_in_endpoint),
487 adu_interrupt_in_callback,
488 dev,
489 dev->interrupt_in_endpoint->bInterval);
490 retval = usb_submit_urb(dev->interrupt_in_urb, GFP_KERNEL);
491 if (retval) {
492 dev->read_urb_finished = 1;
493 if (retval == -ENOMEM) {
494 retval = bytes_read ? bytes_read : -ENOMEM;
495 }
496 dbg(2," %s : submit failed", __func__);
497 goto exit;
498 }
499 }
500
501 /* we wait for I/O to complete */
502 set_current_state(TASK_INTERRUPTIBLE);
503 add_wait_queue(&dev->read_wait, &wait);
504 spin_lock_irqsave(&dev->buflock, flags);
505 if (!dev->read_urb_finished) {
506 spin_unlock_irqrestore(&dev->buflock, flags);
507 timeout = schedule_timeout(COMMAND_TIMEOUT);
508 } else {
509 spin_unlock_irqrestore(&dev->buflock, flags);
510 set_current_state(TASK_RUNNING);
511 }
512 remove_wait_queue(&dev->read_wait, &wait);
513
514 if (timeout <= 0) {
515 dbg(2," %s : timeout", __func__);
516 retval = bytes_read ? bytes_read : -ETIMEDOUT;
517 goto exit;
518 }
519
520 if (signal_pending(current)) {
521 dbg(2," %s : signal pending", __func__);
522 retval = bytes_read ? bytes_read : -EINTR;
523 goto exit;
524 }
525 }
526 }
527 }
528
529 retval = bytes_read;
530 /* if the primary buffer is empty then use it */
531 spin_lock_irqsave(&dev->buflock, flags);
532 if (should_submit && dev->read_urb_finished) {
533 dev->read_urb_finished = 0;
534 spin_unlock_irqrestore(&dev->buflock, flags);
535 usb_fill_int_urb(dev->interrupt_in_urb,dev->udev,
536 usb_rcvintpipe(dev->udev,
537 dev->interrupt_in_endpoint->bEndpointAddress),
538 dev->interrupt_in_buffer,
539 usb_endpoint_maxp(dev->interrupt_in_endpoint),
540 adu_interrupt_in_callback,
541 dev,
542 dev->interrupt_in_endpoint->bInterval);
543 if (usb_submit_urb(dev->interrupt_in_urb, GFP_KERNEL) != 0)
544 dev->read_urb_finished = 1;
545 /* we ignore failure */
546 } else {
547 spin_unlock_irqrestore(&dev->buflock, flags);
548 }
549
550 exit:
551 /* unlock the device */
552 mutex_unlock(&dev->mtx);
553
554 dbg(2," %s : leave, return value %d", __func__, retval);
555 return retval;
556 }
557
558 static ssize_t adu_write(struct file *file, const __user char *buffer,
559 size_t count, loff_t *ppos)
560 {
561 DECLARE_WAITQUEUE(waita, current);
562 struct adu_device *dev;
563 size_t bytes_written = 0;
564 size_t bytes_to_write;
565 size_t buffer_size;
566 unsigned long flags;
567 int retval;
568
569 dbg(2," %s : enter, count = %Zd", __func__, count);
570
571 dev = file->private_data;
572
573 retval = mutex_lock_interruptible(&dev->mtx);
574 if (retval)
575 goto exit_nolock;
576
577 /* verify that the device wasn't unplugged */
578 if (dev->udev == NULL) {
579 retval = -ENODEV;
580 printk(KERN_ERR "adutux: No device or device unplugged %d\n",
581 retval);
582 goto exit;
583 }
584
585 /* verify that we actually have some data to write */
586 if (count == 0) {
587 dbg(1," %s : write request of 0 bytes", __func__);
588 goto exit;
589 }
590
591 while (count > 0) {
592 add_wait_queue(&dev->write_wait, &waita);
593 set_current_state(TASK_INTERRUPTIBLE);
594 spin_lock_irqsave(&dev->buflock, flags);
595 if (!dev->out_urb_finished) {
596 spin_unlock_irqrestore(&dev->buflock, flags);
597
598 mutex_unlock(&dev->mtx);
599 if (signal_pending(current)) {
600 dbg(1," %s : interrupted", __func__);
601 set_current_state(TASK_RUNNING);
602 retval = -EINTR;
603 goto exit_onqueue;
604 }
605 if (schedule_timeout(COMMAND_TIMEOUT) == 0) {
606 dbg(1, "%s - command timed out.", __func__);
607 retval = -ETIMEDOUT;
608 goto exit_onqueue;
609 }
610 remove_wait_queue(&dev->write_wait, &waita);
611 retval = mutex_lock_interruptible(&dev->mtx);
612 if (retval) {
613 retval = bytes_written ? bytes_written : retval;
614 goto exit_nolock;
615 }
616
617 dbg(4," %s : in progress, count = %Zd", __func__, count);
618 } else {
619 spin_unlock_irqrestore(&dev->buflock, flags);
620 set_current_state(TASK_RUNNING);
621 remove_wait_queue(&dev->write_wait, &waita);
622 dbg(4," %s : sending, count = %Zd", __func__, count);
623
624 /* write the data into interrupt_out_buffer from userspace */
625 buffer_size = usb_endpoint_maxp(dev->interrupt_out_endpoint);
626 bytes_to_write = count > buffer_size ? buffer_size : count;
627 dbg(4," %s : buffer_size = %Zd, count = %Zd, bytes_to_write = %Zd",
628 __func__, buffer_size, count, bytes_to_write);
629
630 if (copy_from_user(dev->interrupt_out_buffer, buffer, bytes_to_write) != 0) {
631 retval = -EFAULT;
632 goto exit;
633 }
634
635 /* send off the urb */
636 usb_fill_int_urb(
637 dev->interrupt_out_urb,
638 dev->udev,
639 usb_sndintpipe(dev->udev, dev->interrupt_out_endpoint->bEndpointAddress),
640 dev->interrupt_out_buffer,
641 bytes_to_write,
642 adu_interrupt_out_callback,
643 dev,
644 dev->interrupt_out_endpoint->bInterval);
645 dev->interrupt_out_urb->actual_length = bytes_to_write;
646 dev->out_urb_finished = 0;
647 retval = usb_submit_urb(dev->interrupt_out_urb, GFP_KERNEL);
648 if (retval < 0) {
649 dev->out_urb_finished = 1;
650 dev_err(&dev->udev->dev, "Couldn't submit "
651 "interrupt_out_urb %d\n", retval);
652 goto exit;
653 }
654
655 buffer += bytes_to_write;
656 count -= bytes_to_write;
657
658 bytes_written += bytes_to_write;
659 }
660 }
661 mutex_unlock(&dev->mtx);
662 return bytes_written;
663
664 exit:
665 mutex_unlock(&dev->mtx);
666 exit_nolock:
667 dbg(2," %s : leave, return value %d", __func__, retval);
668 return retval;
669
670 exit_onqueue:
671 remove_wait_queue(&dev->write_wait, &waita);
672 return retval;
673 }
674
675 /* file operations needed when we register this driver */
676 static const struct file_operations adu_fops = {
677 .owner = THIS_MODULE,
678 .read = adu_read,
679 .write = adu_write,
680 .open = adu_open,
681 .release = adu_release,
682 .llseek = noop_llseek,
683 };
684
685 /*
686 * usb class driver info in order to get a minor number from the usb core,
687 * and to have the device registered with devfs and the driver core
688 */
689 static struct usb_class_driver adu_class = {
690 .name = "usb/adutux%d",
691 .fops = &adu_fops,
692 .minor_base = ADU_MINOR_BASE,
693 };
694
695 /**
696 * adu_probe
697 *
698 * Called by the usb core when a new device is connected that it thinks
699 * this driver might be interested in.
700 */
701 static int adu_probe(struct usb_interface *interface,
702 const struct usb_device_id *id)
703 {
704 struct usb_device *udev = interface_to_usbdev(interface);
705 struct adu_device *dev = NULL;
706 struct usb_host_interface *iface_desc;
707 struct usb_endpoint_descriptor *endpoint;
708 int retval = -ENODEV;
709 int in_end_size;
710 int out_end_size;
711 int i;
712
713 dbg(2," %s : enter", __func__);
714
715 if (udev == NULL) {
716 dev_err(&interface->dev, "udev is NULL.\n");
717 goto exit;
718 }
719
720 /* allocate memory for our device state and initialize it */
721 dev = kzalloc(sizeof(struct adu_device), GFP_KERNEL);
722 if (dev == NULL) {
723 dev_err(&interface->dev, "Out of memory\n");
724 retval = -ENOMEM;
725 goto exit;
726 }
727
728 mutex_init(&dev->mtx);
729 spin_lock_init(&dev->buflock);
730 dev->udev = udev;
731 init_waitqueue_head(&dev->read_wait);
732 init_waitqueue_head(&dev->write_wait);
733
734 iface_desc = &interface->altsetting[0];
735
736 /* set up the endpoint information */
737 for (i = 0; i < iface_desc->desc.bNumEndpoints; ++i) {
738 endpoint = &iface_desc->endpoint[i].desc;
739
740 if (usb_endpoint_is_int_in(endpoint))
741 dev->interrupt_in_endpoint = endpoint;
742
743 if (usb_endpoint_is_int_out(endpoint))
744 dev->interrupt_out_endpoint = endpoint;
745 }
746 if (dev->interrupt_in_endpoint == NULL) {
747 dev_err(&interface->dev, "interrupt in endpoint not found\n");
748 goto error;
749 }
750 if (dev->interrupt_out_endpoint == NULL) {
751 dev_err(&interface->dev, "interrupt out endpoint not found\n");
752 goto error;
753 }
754
755 in_end_size = usb_endpoint_maxp(dev->interrupt_in_endpoint);
756 out_end_size = usb_endpoint_maxp(dev->interrupt_out_endpoint);
757
758 dev->read_buffer_primary = kmalloc((4 * in_end_size), GFP_KERNEL);
759 if (!dev->read_buffer_primary) {
760 dev_err(&interface->dev, "Couldn't allocate read_buffer_primary\n");
761 retval = -ENOMEM;
762 goto error;
763 }
764
765 /* debug code prime the buffer */
766 memset(dev->read_buffer_primary, 'a', in_end_size);
767 memset(dev->read_buffer_primary + in_end_size, 'b', in_end_size);
768 memset(dev->read_buffer_primary + (2 * in_end_size), 'c', in_end_size);
769 memset(dev->read_buffer_primary + (3 * in_end_size), 'd', in_end_size);
770
771 dev->read_buffer_secondary = kmalloc((4 * in_end_size), GFP_KERNEL);
772 if (!dev->read_buffer_secondary) {
773 dev_err(&interface->dev, "Couldn't allocate read_buffer_secondary\n");
774 retval = -ENOMEM;
775 goto error;
776 }
777
778 /* debug code prime the buffer */
779 memset(dev->read_buffer_secondary, 'e', in_end_size);
780 memset(dev->read_buffer_secondary + in_end_size, 'f', in_end_size);
781 memset(dev->read_buffer_secondary + (2 * in_end_size), 'g', in_end_size);
782 memset(dev->read_buffer_secondary + (3 * in_end_size), 'h', in_end_size);
783
784 dev->interrupt_in_buffer = kmalloc(in_end_size, GFP_KERNEL);
785 if (!dev->interrupt_in_buffer) {
786 dev_err(&interface->dev, "Couldn't allocate interrupt_in_buffer\n");
787 goto error;
788 }
789
790 /* debug code prime the buffer */
791 memset(dev->interrupt_in_buffer, 'i', in_end_size);
792
793 dev->interrupt_in_urb = usb_alloc_urb(0, GFP_KERNEL);
794 if (!dev->interrupt_in_urb) {
795 dev_err(&interface->dev, "Couldn't allocate interrupt_in_urb\n");
796 goto error;
797 }
798 dev->interrupt_out_buffer = kmalloc(out_end_size, GFP_KERNEL);
799 if (!dev->interrupt_out_buffer) {
800 dev_err(&interface->dev, "Couldn't allocate interrupt_out_buffer\n");
801 goto error;
802 }
803 dev->interrupt_out_urb = usb_alloc_urb(0, GFP_KERNEL);
804 if (!dev->interrupt_out_urb) {
805 dev_err(&interface->dev, "Couldn't allocate interrupt_out_urb\n");
806 goto error;
807 }
808
809 if (!usb_string(udev, udev->descriptor.iSerialNumber, dev->serial_number,
810 sizeof(dev->serial_number))) {
811 dev_err(&interface->dev, "Could not retrieve serial number\n");
812 goto error;
813 }
814 dbg(2," %s : serial_number=%s", __func__, dev->serial_number);
815
816 /* we can register the device now, as it is ready */
817 usb_set_intfdata(interface, dev);
818
819 retval = usb_register_dev(interface, &adu_class);
820
821 if (retval) {
822 /* something prevented us from registering this driver */
823 dev_err(&interface->dev, "Not able to get a minor for this device.\n");
824 usb_set_intfdata(interface, NULL);
825 goto error;
826 }
827
828 dev->minor = interface->minor;
829
830 /* let the user know what node this device is now attached to */
831 dev_info(&interface->dev, "ADU%d %s now attached to /dev/usb/adutux%d\n",
832 udev->descriptor.idProduct, dev->serial_number,
833 (dev->minor - ADU_MINOR_BASE));
834 exit:
835 dbg(2," %s : leave, return value %p (dev)", __func__, dev);
836
837 return retval;
838
839 error:
840 adu_delete(dev);
841 return retval;
842 }
843
844 /**
845 * adu_disconnect
846 *
847 * Called by the usb core when the device is removed from the system.
848 */
849 static void adu_disconnect(struct usb_interface *interface)
850 {
851 struct adu_device *dev;
852 int minor;
853
854 dbg(2," %s : enter", __func__);
855
856 dev = usb_get_intfdata(interface);
857
858 mutex_lock(&dev->mtx); /* not interruptible */
859 dev->udev = NULL; /* poison */
860 minor = dev->minor;
861 usb_deregister_dev(interface, &adu_class);
862 mutex_unlock(&dev->mtx);
863
864 mutex_lock(&adutux_mutex);
865 usb_set_intfdata(interface, NULL);
866
867 /* if the device is not opened, then we clean up right now */
868 dbg(2," %s : open count %d", __func__, dev->open_count);
869 if (!dev->open_count)
870 adu_delete(dev);
871
872 mutex_unlock(&adutux_mutex);
873
874 dev_info(&interface->dev, "ADU device adutux%d now disconnected\n",
875 (minor - ADU_MINOR_BASE));
876
877 dbg(2," %s : leave", __func__);
878 }
879
880 /* usb specific object needed to register this driver with the usb subsystem */
881 static struct usb_driver adu_driver = {
882 .name = "adutux",
883 .probe = adu_probe,
884 .disconnect = adu_disconnect,
885 .id_table = device_table,
886 };
887
888 module_usb_driver(adu_driver);
889
890 MODULE_AUTHOR(DRIVER_AUTHOR);
891 MODULE_DESCRIPTION(DRIVER_DESC);
892 MODULE_LICENSE("GPL");