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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
31static int debug = 5;
32#else
33static int debug = 1;
34#endif
35
36/* Use our own dbg macro */
37#undef dbg
38#define dbg(lvl, format, arg...) \
39do { \
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 */
51module_param(debug, int, S_IRUGO | S_IWUSR);
52MODULE_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 */
59static 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
69MODULE_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 */
93struct 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
123static DEFINE_MUTEX(adutux_mutex);
124
125static struct usb_driver adu_driver;
126
127static 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 */
146static 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
174exit:
175 dbg(2," %s : leave", __func__);
176}
177
178static 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
194static 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 * le16_to_cpu(dev->interrupt_in_endpoint->wMaxPacketSize)) -
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
230exit:
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
240static 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);
261exit:
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
268static 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 le16_to_cpu(dev->interrupt_in_endpoint->wMaxPacketSize),
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
332exit_no_device:
333 mutex_unlock(&adutux_mutex);
334exit_no_lock:
335 dbg(2,"%s : leave, return value %d ", __func__, retval);
336 return retval;
337}
338
339static 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
354static 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 }
388unlock:
389 mutex_unlock(&adutux_mutex);
390exit:
391 dbg(2," %s : leave, return value %d", __func__, retval);
392 return retval;
393}
394
395static 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 le16_to_cpu(dev->interrupt_in_endpoint->wMaxPacketSize),
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 le16_to_cpu(dev->interrupt_in_endpoint->wMaxPacketSize),
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
550exit:
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
558static 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 = le16_to_cpu(dev->interrupt_out_endpoint->wMaxPacketSize);
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
664exit:
665 mutex_unlock(&dev->mtx);
666exit_nolock:
667 dbg(2," %s : leave, return value %d", __func__, retval);
668 return retval;
669
670exit_onqueue:
671 remove_wait_queue(&dev->write_wait, &waita);
672 return retval;
673}
674
675/* file operations needed when we register this driver */
676static 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 */
689static 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 */
701static 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 = le16_to_cpu(dev->interrupt_in_endpoint->wMaxPacketSize);
756 out_end_size = le16_to_cpu(dev->interrupt_out_endpoint->wMaxPacketSize);
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));
834exit:
835 dbg(2," %s : leave, return value %p (dev)", __func__, dev);
836
837 return retval;
838
839error:
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 */
849static 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 */
881static struct usb_driver adu_driver = {
882 .name = "adutux",
883 .probe = adu_probe,
884 .disconnect = adu_disconnect,
885 .id_table = device_table,
886};
887
888static int __init adu_init(void)
889{
890 int result;
891
892 dbg(2," %s : enter", __func__);
893
894 /* register this driver with the USB subsystem */
895 result = usb_register(&adu_driver);
896 if (result < 0) {
897 printk(KERN_ERR "usb_register failed for the "__FILE__
898 " driver. Error number %d\n", result);
899 goto exit;
900 }
901
902 printk(KERN_INFO "adutux " DRIVER_DESC " " DRIVER_VERSION "\n");
903 printk(KERN_INFO "adutux is an experimental driver. "
904 "Use at your own risk\n");
905
906exit:
907 dbg(2," %s : leave, return value %d", __func__, result);
908
909 return result;
910}
911
912static void __exit adu_exit(void)
913{
914 dbg(2," %s : enter", __func__);
915 /* deregister this driver with the USB subsystem */
916 usb_deregister(&adu_driver);
917 dbg(2," %s : leave", __func__);
918}
919
920module_init(adu_init);
921module_exit(adu_exit);
922
923MODULE_AUTHOR(DRIVER_AUTHOR);
924MODULE_DESCRIPTION(DRIVER_DESC);
925MODULE_LICENSE("GPL");
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#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
22
23#include <linux/kernel.h>
24#include <linux/errno.h>
25#include <linux/slab.h>
26#include <linux/module.h>
27#include <linux/usb.h>
28#include <linux/mutex.h>
29#include <linux/uaccess.h>
30
31/* Version Information */
32#define DRIVER_VERSION "v0.0.13"
33#define DRIVER_AUTHOR "John Homppi"
34#define DRIVER_DESC "adutux (see www.ontrak.net)"
35
36/* Define these values to match your device */
37#define ADU_VENDOR_ID 0x0a07
38#define ADU_PRODUCT_ID 0x0064
39
40/* table of devices that work with this driver */
41static const struct usb_device_id device_table[] = {
42 { USB_DEVICE(ADU_VENDOR_ID, ADU_PRODUCT_ID) }, /* ADU100 */
43 { USB_DEVICE(ADU_VENDOR_ID, ADU_PRODUCT_ID+20) }, /* ADU120 */
44 { USB_DEVICE(ADU_VENDOR_ID, ADU_PRODUCT_ID+30) }, /* ADU130 */
45 { USB_DEVICE(ADU_VENDOR_ID, ADU_PRODUCT_ID+100) }, /* ADU200 */
46 { USB_DEVICE(ADU_VENDOR_ID, ADU_PRODUCT_ID+108) }, /* ADU208 */
47 { USB_DEVICE(ADU_VENDOR_ID, ADU_PRODUCT_ID+118) }, /* ADU218 */
48 { } /* Terminating entry */
49};
50
51MODULE_DEVICE_TABLE(usb, device_table);
52
53#ifdef CONFIG_USB_DYNAMIC_MINORS
54#define ADU_MINOR_BASE 0
55#else
56#define ADU_MINOR_BASE 67
57#endif
58
59/* we can have up to this number of device plugged in at once */
60#define MAX_DEVICES 16
61
62#define COMMAND_TIMEOUT (2*HZ) /* 60 second timeout for a command */
63
64/*
65 * The locking scheme is a vanilla 3-lock:
66 * adu_device.buflock: A spinlock, covers what IRQs touch.
67 * adutux_mutex: A Static lock to cover open_count. It would also cover
68 * any globals, but we don't have them in 2.6.
69 * adu_device.mtx: A mutex to hold across sleepers like copy_from_user.
70 * It covers all of adu_device, except the open_count
71 * and what .buflock covers.
72 */
73
74/* Structure to hold all of our device specific stuff */
75struct adu_device {
76 struct mutex mtx;
77 struct usb_device *udev; /* save off the usb device pointer */
78 struct usb_interface *interface;
79 unsigned int minor; /* the starting minor number for this device */
80 char serial_number[8];
81
82 int open_count; /* number of times this port has been opened */
83
84 char *read_buffer_primary;
85 int read_buffer_length;
86 char *read_buffer_secondary;
87 int secondary_head;
88 int secondary_tail;
89 spinlock_t buflock;
90
91 wait_queue_head_t read_wait;
92 wait_queue_head_t write_wait;
93
94 char *interrupt_in_buffer;
95 struct usb_endpoint_descriptor *interrupt_in_endpoint;
96 struct urb *interrupt_in_urb;
97 int read_urb_finished;
98
99 char *interrupt_out_buffer;
100 struct usb_endpoint_descriptor *interrupt_out_endpoint;
101 struct urb *interrupt_out_urb;
102 int out_urb_finished;
103};
104
105static DEFINE_MUTEX(adutux_mutex);
106
107static struct usb_driver adu_driver;
108
109static inline void adu_debug_data(struct device *dev, const char *function,
110 int size, const unsigned char *data)
111{
112 dev_dbg(dev, "%s - length = %d, data = %*ph\n",
113 function, size, size, data);
114}
115
116/**
117 * adu_abort_transfers
118 * aborts transfers and frees associated data structures
119 */
120static void adu_abort_transfers(struct adu_device *dev)
121{
122 unsigned long flags;
123
124 if (dev->udev == NULL)
125 return;
126
127 /* shutdown transfer */
128
129 /* XXX Anchor these instead */
130 spin_lock_irqsave(&dev->buflock, flags);
131 if (!dev->read_urb_finished) {
132 spin_unlock_irqrestore(&dev->buflock, flags);
133 usb_kill_urb(dev->interrupt_in_urb);
134 } else
135 spin_unlock_irqrestore(&dev->buflock, flags);
136
137 spin_lock_irqsave(&dev->buflock, flags);
138 if (!dev->out_urb_finished) {
139 spin_unlock_irqrestore(&dev->buflock, flags);
140 usb_kill_urb(dev->interrupt_out_urb);
141 } else
142 spin_unlock_irqrestore(&dev->buflock, flags);
143}
144
145static void adu_delete(struct adu_device *dev)
146{
147 /* free data structures */
148 usb_free_urb(dev->interrupt_in_urb);
149 usb_free_urb(dev->interrupt_out_urb);
150 kfree(dev->read_buffer_primary);
151 kfree(dev->read_buffer_secondary);
152 kfree(dev->interrupt_in_buffer);
153 kfree(dev->interrupt_out_buffer);
154 kfree(dev);
155}
156
157static void adu_interrupt_in_callback(struct urb *urb)
158{
159 struct adu_device *dev = urb->context;
160 int status = urb->status;
161
162 adu_debug_data(&dev->udev->dev, __func__,
163 urb->actual_length, urb->transfer_buffer);
164
165 spin_lock(&dev->buflock);
166
167 if (status != 0) {
168 if ((status != -ENOENT) && (status != -ECONNRESET) &&
169 (status != -ESHUTDOWN)) {
170 dev_dbg(&dev->udev->dev,
171 "%s : nonzero status received: %d\n",
172 __func__, status);
173 }
174 goto exit;
175 }
176
177 if (urb->actual_length > 0 && dev->interrupt_in_buffer[0] != 0x00) {
178 if (dev->read_buffer_length <
179 (4 * usb_endpoint_maxp(dev->interrupt_in_endpoint)) -
180 (urb->actual_length)) {
181 memcpy (dev->read_buffer_primary +
182 dev->read_buffer_length,
183 dev->interrupt_in_buffer, urb->actual_length);
184
185 dev->read_buffer_length += urb->actual_length;
186 dev_dbg(&dev->udev->dev,"%s reading %d\n", __func__,
187 urb->actual_length);
188 } else {
189 dev_dbg(&dev->udev->dev,"%s : read_buffer overflow\n",
190 __func__);
191 }
192 }
193
194exit:
195 dev->read_urb_finished = 1;
196 spin_unlock(&dev->buflock);
197 /* always wake up so we recover from errors */
198 wake_up_interruptible(&dev->read_wait);
199}
200
201static void adu_interrupt_out_callback(struct urb *urb)
202{
203 struct adu_device *dev = urb->context;
204 int status = urb->status;
205
206 adu_debug_data(&dev->udev->dev, __func__,
207 urb->actual_length, urb->transfer_buffer);
208
209 if (status != 0) {
210 if ((status != -ENOENT) &&
211 (status != -ECONNRESET)) {
212 dev_dbg(&dev->udev->dev,
213 "%s :nonzero status received: %d\n", __func__,
214 status);
215 }
216 return;
217 }
218
219 spin_lock(&dev->buflock);
220 dev->out_urb_finished = 1;
221 wake_up(&dev->write_wait);
222 spin_unlock(&dev->buflock);
223}
224
225static int adu_open(struct inode *inode, struct file *file)
226{
227 struct adu_device *dev = NULL;
228 struct usb_interface *interface;
229 int subminor;
230 int retval;
231
232 subminor = iminor(inode);
233
234 retval = mutex_lock_interruptible(&adutux_mutex);
235 if (retval)
236 goto exit_no_lock;
237
238 interface = usb_find_interface(&adu_driver, subminor);
239 if (!interface) {
240 pr_err("%s - error, can't find device for minor %d\n",
241 __func__, subminor);
242 retval = -ENODEV;
243 goto exit_no_device;
244 }
245
246 dev = usb_get_intfdata(interface);
247 if (!dev || !dev->udev) {
248 retval = -ENODEV;
249 goto exit_no_device;
250 }
251
252 /* check that nobody else is using the device */
253 if (dev->open_count) {
254 retval = -EBUSY;
255 goto exit_no_device;
256 }
257
258 ++dev->open_count;
259 dev_dbg(&dev->udev->dev, "%s: open count %d\n", __func__,
260 dev->open_count);
261
262 /* save device in the file's private structure */
263 file->private_data = dev;
264
265 /* initialize in direction */
266 dev->read_buffer_length = 0;
267
268 /* fixup first read by having urb waiting for it */
269 usb_fill_int_urb(dev->interrupt_in_urb, dev->udev,
270 usb_rcvintpipe(dev->udev,
271 dev->interrupt_in_endpoint->bEndpointAddress),
272 dev->interrupt_in_buffer,
273 usb_endpoint_maxp(dev->interrupt_in_endpoint),
274 adu_interrupt_in_callback, dev,
275 dev->interrupt_in_endpoint->bInterval);
276 dev->read_urb_finished = 0;
277 if (usb_submit_urb(dev->interrupt_in_urb, GFP_KERNEL))
278 dev->read_urb_finished = 1;
279 /* we ignore failure */
280 /* end of fixup for first read */
281
282 /* initialize out direction */
283 dev->out_urb_finished = 1;
284
285 retval = 0;
286
287exit_no_device:
288 mutex_unlock(&adutux_mutex);
289exit_no_lock:
290 return retval;
291}
292
293static void adu_release_internal(struct adu_device *dev)
294{
295 /* decrement our usage count for the device */
296 --dev->open_count;
297 dev_dbg(&dev->udev->dev, "%s : open count %d\n", __func__,
298 dev->open_count);
299 if (dev->open_count <= 0) {
300 adu_abort_transfers(dev);
301 dev->open_count = 0;
302 }
303}
304
305static int adu_release(struct inode *inode, struct file *file)
306{
307 struct adu_device *dev;
308 int retval = 0;
309
310 if (file == NULL) {
311 retval = -ENODEV;
312 goto exit;
313 }
314
315 dev = file->private_data;
316 if (dev == NULL) {
317 retval = -ENODEV;
318 goto exit;
319 }
320
321 mutex_lock(&adutux_mutex); /* not interruptible */
322
323 if (dev->open_count <= 0) {
324 dev_dbg(&dev->udev->dev, "%s : device not opened\n", __func__);
325 retval = -ENODEV;
326 goto unlock;
327 }
328
329 adu_release_internal(dev);
330 if (dev->udev == NULL) {
331 /* the device was unplugged before the file was released */
332 if (!dev->open_count) /* ... and we're the last user */
333 adu_delete(dev);
334 }
335unlock:
336 mutex_unlock(&adutux_mutex);
337exit:
338 return retval;
339}
340
341static ssize_t adu_read(struct file *file, __user char *buffer, size_t count,
342 loff_t *ppos)
343{
344 struct adu_device *dev;
345 size_t bytes_read = 0;
346 size_t bytes_to_read = count;
347 int i;
348 int retval = 0;
349 int timeout = 0;
350 int should_submit = 0;
351 unsigned long flags;
352 DECLARE_WAITQUEUE(wait, current);
353
354 dev = file->private_data;
355 if (mutex_lock_interruptible(&dev->mtx))
356 return -ERESTARTSYS;
357
358 /* verify that the device wasn't unplugged */
359 if (dev->udev == NULL) {
360 retval = -ENODEV;
361 pr_err("No device or device unplugged %d\n", retval);
362 goto exit;
363 }
364
365 /* verify that some data was requested */
366 if (count == 0) {
367 dev_dbg(&dev->udev->dev, "%s : read request of 0 bytes\n",
368 __func__);
369 goto exit;
370 }
371
372 timeout = COMMAND_TIMEOUT;
373 dev_dbg(&dev->udev->dev, "%s : about to start looping\n", __func__);
374 while (bytes_to_read) {
375 int data_in_secondary = dev->secondary_tail - dev->secondary_head;
376 dev_dbg(&dev->udev->dev,
377 "%s : while, data_in_secondary=%d, status=%d\n",
378 __func__, data_in_secondary,
379 dev->interrupt_in_urb->status);
380
381 if (data_in_secondary) {
382 /* drain secondary buffer */
383 int amount = bytes_to_read < data_in_secondary ? bytes_to_read : data_in_secondary;
384 i = copy_to_user(buffer, dev->read_buffer_secondary+dev->secondary_head, amount);
385 if (i) {
386 retval = -EFAULT;
387 goto exit;
388 }
389 dev->secondary_head += (amount - i);
390 bytes_read += (amount - i);
391 bytes_to_read -= (amount - i);
392 if (i) {
393 retval = bytes_read ? bytes_read : -EFAULT;
394 goto exit;
395 }
396 } else {
397 /* we check the primary buffer */
398 spin_lock_irqsave (&dev->buflock, flags);
399 if (dev->read_buffer_length) {
400 /* we secure access to the primary */
401 char *tmp;
402 dev_dbg(&dev->udev->dev,
403 "%s : swap, read_buffer_length = %d\n",
404 __func__, dev->read_buffer_length);
405 tmp = dev->read_buffer_secondary;
406 dev->read_buffer_secondary = dev->read_buffer_primary;
407 dev->read_buffer_primary = tmp;
408 dev->secondary_head = 0;
409 dev->secondary_tail = dev->read_buffer_length;
410 dev->read_buffer_length = 0;
411 spin_unlock_irqrestore(&dev->buflock, flags);
412 /* we have a free buffer so use it */
413 should_submit = 1;
414 } else {
415 /* even the primary was empty - we may need to do IO */
416 if (!dev->read_urb_finished) {
417 /* somebody is doing IO */
418 spin_unlock_irqrestore(&dev->buflock, flags);
419 dev_dbg(&dev->udev->dev,
420 "%s : submitted already\n",
421 __func__);
422 } else {
423 /* we must initiate input */
424 dev_dbg(&dev->udev->dev,
425 "%s : initiate input\n",
426 __func__);
427 dev->read_urb_finished = 0;
428 spin_unlock_irqrestore(&dev->buflock, flags);
429
430 usb_fill_int_urb(dev->interrupt_in_urb, dev->udev,
431 usb_rcvintpipe(dev->udev,
432 dev->interrupt_in_endpoint->bEndpointAddress),
433 dev->interrupt_in_buffer,
434 usb_endpoint_maxp(dev->interrupt_in_endpoint),
435 adu_interrupt_in_callback,
436 dev,
437 dev->interrupt_in_endpoint->bInterval);
438 retval = usb_submit_urb(dev->interrupt_in_urb, GFP_KERNEL);
439 if (retval) {
440 dev->read_urb_finished = 1;
441 if (retval == -ENOMEM) {
442 retval = bytes_read ? bytes_read : -ENOMEM;
443 }
444 dev_dbg(&dev->udev->dev,
445 "%s : submit failed\n",
446 __func__);
447 goto exit;
448 }
449 }
450
451 /* we wait for I/O to complete */
452 set_current_state(TASK_INTERRUPTIBLE);
453 add_wait_queue(&dev->read_wait, &wait);
454 spin_lock_irqsave(&dev->buflock, flags);
455 if (!dev->read_urb_finished) {
456 spin_unlock_irqrestore(&dev->buflock, flags);
457 timeout = schedule_timeout(COMMAND_TIMEOUT);
458 } else {
459 spin_unlock_irqrestore(&dev->buflock, flags);
460 set_current_state(TASK_RUNNING);
461 }
462 remove_wait_queue(&dev->read_wait, &wait);
463
464 if (timeout <= 0) {
465 dev_dbg(&dev->udev->dev,
466 "%s : timeout\n", __func__);
467 retval = bytes_read ? bytes_read : -ETIMEDOUT;
468 goto exit;
469 }
470
471 if (signal_pending(current)) {
472 dev_dbg(&dev->udev->dev,
473 "%s : signal pending\n",
474 __func__);
475 retval = bytes_read ? bytes_read : -EINTR;
476 goto exit;
477 }
478 }
479 }
480 }
481
482 retval = bytes_read;
483 /* if the primary buffer is empty then use it */
484 spin_lock_irqsave(&dev->buflock, flags);
485 if (should_submit && dev->read_urb_finished) {
486 dev->read_urb_finished = 0;
487 spin_unlock_irqrestore(&dev->buflock, flags);
488 usb_fill_int_urb(dev->interrupt_in_urb, dev->udev,
489 usb_rcvintpipe(dev->udev,
490 dev->interrupt_in_endpoint->bEndpointAddress),
491 dev->interrupt_in_buffer,
492 usb_endpoint_maxp(dev->interrupt_in_endpoint),
493 adu_interrupt_in_callback,
494 dev,
495 dev->interrupt_in_endpoint->bInterval);
496 if (usb_submit_urb(dev->interrupt_in_urb, GFP_KERNEL) != 0)
497 dev->read_urb_finished = 1;
498 /* we ignore failure */
499 } else {
500 spin_unlock_irqrestore(&dev->buflock, flags);
501 }
502
503exit:
504 /* unlock the device */
505 mutex_unlock(&dev->mtx);
506
507 return retval;
508}
509
510static ssize_t adu_write(struct file *file, const __user char *buffer,
511 size_t count, loff_t *ppos)
512{
513 DECLARE_WAITQUEUE(waita, current);
514 struct adu_device *dev;
515 size_t bytes_written = 0;
516 size_t bytes_to_write;
517 size_t buffer_size;
518 unsigned long flags;
519 int retval;
520
521 dev = file->private_data;
522
523 retval = mutex_lock_interruptible(&dev->mtx);
524 if (retval)
525 goto exit_nolock;
526
527 /* verify that the device wasn't unplugged */
528 if (dev->udev == NULL) {
529 retval = -ENODEV;
530 pr_err("No device or device unplugged %d\n", retval);
531 goto exit;
532 }
533
534 /* verify that we actually have some data to write */
535 if (count == 0) {
536 dev_dbg(&dev->udev->dev, "%s : write request of 0 bytes\n",
537 __func__);
538 goto exit;
539 }
540
541 while (count > 0) {
542 add_wait_queue(&dev->write_wait, &waita);
543 set_current_state(TASK_INTERRUPTIBLE);
544 spin_lock_irqsave(&dev->buflock, flags);
545 if (!dev->out_urb_finished) {
546 spin_unlock_irqrestore(&dev->buflock, flags);
547
548 mutex_unlock(&dev->mtx);
549 if (signal_pending(current)) {
550 dev_dbg(&dev->udev->dev, "%s : interrupted\n",
551 __func__);
552 set_current_state(TASK_RUNNING);
553 retval = -EINTR;
554 goto exit_onqueue;
555 }
556 if (schedule_timeout(COMMAND_TIMEOUT) == 0) {
557 dev_dbg(&dev->udev->dev,
558 "%s - command timed out.\n", __func__);
559 retval = -ETIMEDOUT;
560 goto exit_onqueue;
561 }
562 remove_wait_queue(&dev->write_wait, &waita);
563 retval = mutex_lock_interruptible(&dev->mtx);
564 if (retval) {
565 retval = bytes_written ? bytes_written : retval;
566 goto exit_nolock;
567 }
568
569 dev_dbg(&dev->udev->dev,
570 "%s : in progress, count = %Zd\n",
571 __func__, count);
572 } else {
573 spin_unlock_irqrestore(&dev->buflock, flags);
574 set_current_state(TASK_RUNNING);
575 remove_wait_queue(&dev->write_wait, &waita);
576 dev_dbg(&dev->udev->dev, "%s : sending, count = %Zd\n",
577 __func__, count);
578
579 /* write the data into interrupt_out_buffer from userspace */
580 buffer_size = usb_endpoint_maxp(dev->interrupt_out_endpoint);
581 bytes_to_write = count > buffer_size ? buffer_size : count;
582 dev_dbg(&dev->udev->dev,
583 "%s : buffer_size = %Zd, count = %Zd, bytes_to_write = %Zd\n",
584 __func__, buffer_size, count, bytes_to_write);
585
586 if (copy_from_user(dev->interrupt_out_buffer, buffer, bytes_to_write) != 0) {
587 retval = -EFAULT;
588 goto exit;
589 }
590
591 /* send off the urb */
592 usb_fill_int_urb(
593 dev->interrupt_out_urb,
594 dev->udev,
595 usb_sndintpipe(dev->udev, dev->interrupt_out_endpoint->bEndpointAddress),
596 dev->interrupt_out_buffer,
597 bytes_to_write,
598 adu_interrupt_out_callback,
599 dev,
600 dev->interrupt_out_endpoint->bInterval);
601 dev->interrupt_out_urb->actual_length = bytes_to_write;
602 dev->out_urb_finished = 0;
603 retval = usb_submit_urb(dev->interrupt_out_urb, GFP_KERNEL);
604 if (retval < 0) {
605 dev->out_urb_finished = 1;
606 dev_err(&dev->udev->dev, "Couldn't submit "
607 "interrupt_out_urb %d\n", retval);
608 goto exit;
609 }
610
611 buffer += bytes_to_write;
612 count -= bytes_to_write;
613
614 bytes_written += bytes_to_write;
615 }
616 }
617 mutex_unlock(&dev->mtx);
618 return bytes_written;
619
620exit:
621 mutex_unlock(&dev->mtx);
622exit_nolock:
623 return retval;
624
625exit_onqueue:
626 remove_wait_queue(&dev->write_wait, &waita);
627 return retval;
628}
629
630/* file operations needed when we register this driver */
631static const struct file_operations adu_fops = {
632 .owner = THIS_MODULE,
633 .read = adu_read,
634 .write = adu_write,
635 .open = adu_open,
636 .release = adu_release,
637 .llseek = noop_llseek,
638};
639
640/*
641 * usb class driver info in order to get a minor number from the usb core,
642 * and to have the device registered with devfs and the driver core
643 */
644static struct usb_class_driver adu_class = {
645 .name = "usb/adutux%d",
646 .fops = &adu_fops,
647 .minor_base = ADU_MINOR_BASE,
648};
649
650/**
651 * adu_probe
652 *
653 * Called by the usb core when a new device is connected that it thinks
654 * this driver might be interested in.
655 */
656static int adu_probe(struct usb_interface *interface,
657 const struct usb_device_id *id)
658{
659 struct usb_device *udev = interface_to_usbdev(interface);
660 struct adu_device *dev = NULL;
661 struct usb_host_interface *iface_desc;
662 struct usb_endpoint_descriptor *endpoint;
663 int retval = -ENODEV;
664 int in_end_size;
665 int out_end_size;
666 int i;
667
668 if (udev == NULL) {
669 dev_err(&interface->dev, "udev is NULL.\n");
670 goto exit;
671 }
672
673 /* allocate memory for our device state and initialize it */
674 dev = kzalloc(sizeof(struct adu_device), GFP_KERNEL);
675 if (!dev) {
676 retval = -ENOMEM;
677 goto exit;
678 }
679
680 mutex_init(&dev->mtx);
681 spin_lock_init(&dev->buflock);
682 dev->udev = udev;
683 init_waitqueue_head(&dev->read_wait);
684 init_waitqueue_head(&dev->write_wait);
685
686 iface_desc = &interface->altsetting[0];
687
688 /* set up the endpoint information */
689 for (i = 0; i < iface_desc->desc.bNumEndpoints; ++i) {
690 endpoint = &iface_desc->endpoint[i].desc;
691
692 if (usb_endpoint_is_int_in(endpoint))
693 dev->interrupt_in_endpoint = endpoint;
694
695 if (usb_endpoint_is_int_out(endpoint))
696 dev->interrupt_out_endpoint = endpoint;
697 }
698 if (dev->interrupt_in_endpoint == NULL) {
699 dev_err(&interface->dev, "interrupt in endpoint not found\n");
700 goto error;
701 }
702 if (dev->interrupt_out_endpoint == NULL) {
703 dev_err(&interface->dev, "interrupt out endpoint not found\n");
704 goto error;
705 }
706
707 in_end_size = usb_endpoint_maxp(dev->interrupt_in_endpoint);
708 out_end_size = usb_endpoint_maxp(dev->interrupt_out_endpoint);
709
710 dev->read_buffer_primary = kmalloc((4 * in_end_size), GFP_KERNEL);
711 if (!dev->read_buffer_primary) {
712 retval = -ENOMEM;
713 goto error;
714 }
715
716 /* debug code prime the buffer */
717 memset(dev->read_buffer_primary, 'a', in_end_size);
718 memset(dev->read_buffer_primary + in_end_size, 'b', in_end_size);
719 memset(dev->read_buffer_primary + (2 * in_end_size), 'c', in_end_size);
720 memset(dev->read_buffer_primary + (3 * in_end_size), 'd', in_end_size);
721
722 dev->read_buffer_secondary = kmalloc((4 * in_end_size), GFP_KERNEL);
723 if (!dev->read_buffer_secondary) {
724 retval = -ENOMEM;
725 goto error;
726 }
727
728 /* debug code prime the buffer */
729 memset(dev->read_buffer_secondary, 'e', in_end_size);
730 memset(dev->read_buffer_secondary + in_end_size, 'f', in_end_size);
731 memset(dev->read_buffer_secondary + (2 * in_end_size), 'g', in_end_size);
732 memset(dev->read_buffer_secondary + (3 * in_end_size), 'h', in_end_size);
733
734 dev->interrupt_in_buffer = kmalloc(in_end_size, GFP_KERNEL);
735 if (!dev->interrupt_in_buffer)
736 goto error;
737
738 /* debug code prime the buffer */
739 memset(dev->interrupt_in_buffer, 'i', in_end_size);
740
741 dev->interrupt_in_urb = usb_alloc_urb(0, GFP_KERNEL);
742 if (!dev->interrupt_in_urb)
743 goto error;
744 dev->interrupt_out_buffer = kmalloc(out_end_size, GFP_KERNEL);
745 if (!dev->interrupt_out_buffer)
746 goto error;
747 dev->interrupt_out_urb = usb_alloc_urb(0, GFP_KERNEL);
748 if (!dev->interrupt_out_urb)
749 goto error;
750
751 if (!usb_string(udev, udev->descriptor.iSerialNumber, dev->serial_number,
752 sizeof(dev->serial_number))) {
753 dev_err(&interface->dev, "Could not retrieve serial number\n");
754 goto error;
755 }
756 dev_dbg(&interface->dev,"serial_number=%s", dev->serial_number);
757
758 /* we can register the device now, as it is ready */
759 usb_set_intfdata(interface, dev);
760
761 retval = usb_register_dev(interface, &adu_class);
762
763 if (retval) {
764 /* something prevented us from registering this driver */
765 dev_err(&interface->dev, "Not able to get a minor for this device.\n");
766 usb_set_intfdata(interface, NULL);
767 goto error;
768 }
769
770 dev->minor = interface->minor;
771
772 /* let the user know what node this device is now attached to */
773 dev_info(&interface->dev, "ADU%d %s now attached to /dev/usb/adutux%d\n",
774 le16_to_cpu(udev->descriptor.idProduct), dev->serial_number,
775 (dev->minor - ADU_MINOR_BASE));
776exit:
777 return retval;
778
779error:
780 adu_delete(dev);
781 return retval;
782}
783
784/**
785 * adu_disconnect
786 *
787 * Called by the usb core when the device is removed from the system.
788 */
789static void adu_disconnect(struct usb_interface *interface)
790{
791 struct adu_device *dev;
792 int minor;
793
794 dev = usb_get_intfdata(interface);
795
796 mutex_lock(&dev->mtx); /* not interruptible */
797 dev->udev = NULL; /* poison */
798 minor = dev->minor;
799 usb_deregister_dev(interface, &adu_class);
800 mutex_unlock(&dev->mtx);
801
802 mutex_lock(&adutux_mutex);
803 usb_set_intfdata(interface, NULL);
804
805 /* if the device is not opened, then we clean up right now */
806 if (!dev->open_count)
807 adu_delete(dev);
808
809 mutex_unlock(&adutux_mutex);
810}
811
812/* usb specific object needed to register this driver with the usb subsystem */
813static struct usb_driver adu_driver = {
814 .name = "adutux",
815 .probe = adu_probe,
816 .disconnect = adu_disconnect,
817 .id_table = device_table,
818};
819
820module_usb_driver(adu_driver);
821
822MODULE_AUTHOR(DRIVER_AUTHOR);
823MODULE_DESCRIPTION(DRIVER_DESC);
824MODULE_LICENSE("GPL");