1 /*
2 * Frontier Designs Alphatrack driver
3 *
4 * Copyright (C) 2007 Michael Taht (m@taht.net)
5 *
6 * Based on the usbled driver and ldusb drivers by
7 *
8 * Copyright (C) 2004 Greg Kroah-Hartman (greg@kroah.com)
9 * Copyright (C) 2005 Michael Hund <mhund@ld-didactic.de>
10 *
11 * The ldusb driver was, in turn, derived from Lego USB Tower driver
12 * Copyright (C) 2003 David Glance <advidgsf@sourceforge.net>
13 * 2001-2004 Juergen Stuber <starblue@users.sourceforge.net>
14 *
15 * This program is free software; you can redistribute it and/or
16 * modify it under the terms of the GNU General Public License as
17 * published by the Free Software Foundation, version 2.
18 *
19 */
20
21 /**
22 * This driver uses a ring buffer for time critical reading of
23 * interrupt in reports and provides read and write methods for
24 * raw interrupt reports.
25 */
26
27 /* Note: this currently uses a dumb ringbuffer for reads and writes.
28 * A more optimal driver would cache and kill off outstanding urbs that are
29 * now invalid, and ignore ones that already were in the queue but valid
30 * as we only have 30 commands for the alphatrack. In particular this is
31 * key for getting lights to flash in time as otherwise many commands
32 * can be buffered up before the light change makes it to the interface.
33 */
34
35 #include <linux/kernel.h>
36 #include <linux/errno.h>
37 #include <linux/init.h>
38 #include <linux/slab.h>
39 #include <linux/module.h>
40 #include <linux/kobject.h>
41 #include <linux/mutex.h>
42
43 #include <linux/uaccess.h>
44 #include <linux/input.h>
45 #include <linux/usb.h>
46 #include <linux/poll.h>
47
48 #include "alphatrack.h"
49
50 #define VENDOR_ID 0x165b
51 #define PRODUCT_ID 0xfad1
52
53 #ifdef CONFIG_USB_DYNAMIC_MINORS
54 #define USB_ALPHATRACK_MINOR_BASE 0
55 #else
56 /* FIXME 176 - is another driver's minor - apply for that */
57 #define USB_ALPHATRACK_MINOR_BASE 176
58 #endif
59
60 /* table of devices that work with this driver */
61 static const struct usb_device_id usb_alphatrack_table[] = {
62 {USB_DEVICE(VENDOR_ID, PRODUCT_ID)},
63 {} /* Terminating entry */
64 };
65
66 MODULE_DEVICE_TABLE(usb, usb_alphatrack_table);
67 MODULE_VERSION("0.41");
68 MODULE_AUTHOR("Mike Taht <m@taht.net>");
69 MODULE_DESCRIPTION("Alphatrack USB Driver");
70 MODULE_LICENSE("GPL");
71 MODULE_SUPPORTED_DEVICE("Frontier Designs Alphatrack Control Surface");
72
73 /* These aren't done yet */
74
75 #define SUPPRESS_EXTRA_ONLINE_EVENTS 0
76 #define BUFFERED_WRITES 0
77 #define SUPPRESS_EXTRA_OFFLINE_EVENTS 0
78 #define COMPRESS_FADER_EVENTS 0
79
80 #define BUFFERED_READS 1
81 #define RING_BUFFER_SIZE 512
82 #define WRITE_BUFFER_SIZE 34
83 #define ALPHATRACK_USB_TIMEOUT 10
84 #define OUTPUT_CMD_SIZE 8
85 #define INPUT_CMD_SIZE 12
86 #define ALPHATRACK_DEBUG 0
87
88 static int debug = ALPHATRACK_DEBUG;
89
90 /* Use our own dbg macro */
91 #define dbg_info(dev, format, arg...) do \
92 { if (debug) dev_info(dev , format , ## arg); } while (0)
93
94 #define alphatrack_ocmd_info(dev, cmd, format, arg...)
95
96 #define alphatrack_icmd_info(dev, cmd, format, arg...)
97
98 /* Module parameters */
99
100 module_param(debug, int, S_IRUGO | S_IWUSR);
101 MODULE_PARM_DESC(debug, "Debug enabled or not");
102
103 /* All interrupt in transfers are collected in a ring buffer to
104 * avoid racing conditions and get better performance of the driver.
105 */
106
107 static int ring_buffer_size = RING_BUFFER_SIZE;
108
109 module_param(ring_buffer_size, int, S_IRUGO);
110 MODULE_PARM_DESC(ring_buffer_size, "Read ring buffer size");
111
112 /* The write_buffer can one day contain more than one interrupt out transfer.
113 */
114
115 static int write_buffer_size = WRITE_BUFFER_SIZE;
116 module_param(write_buffer_size, int, S_IRUGO);
117 MODULE_PARM_DESC(write_buffer_size, "Write buffer size");
118
119 /*
120 * Increase the interval for debugging purposes.
121 * or set to 1 to use the standard interval from the endpoint descriptors.
122 */
123
124 static int min_interrupt_in_interval = ALPHATRACK_USB_TIMEOUT;
125 module_param(min_interrupt_in_interval, int, 0);
126 MODULE_PARM_DESC(min_interrupt_in_interval,
127 "Minimum interrupt in interval in ms");
128
129 static int min_interrupt_out_interval = ALPHATRACK_USB_TIMEOUT;
130 module_param(min_interrupt_out_interval, int, 0);
131 MODULE_PARM_DESC(min_interrupt_out_interval,
132 "Minimum interrupt out interval in ms");
133
134 /* Structure to hold all of our device specific stuff */
135
136 struct usb_alphatrack {
137 struct mutex mtx; /* locks this structure */
138 struct usb_interface *intf; /* save off the usb interface pointer */
139 int open_count; /* number of times this port has been opened */
140
141 /* make gcc happy */
142 struct alphatrack_icmd (*ring_buffer)[RING_BUFFER_SIZE];
143 struct alphatrack_ocmd (*write_buffer)[WRITE_BUFFER_SIZE];
144 unsigned int ring_head;
145 unsigned int ring_tail;
146
147 wait_queue_head_t read_wait;
148 wait_queue_head_t write_wait;
149
150 unsigned char *interrupt_in_buffer;
151 unsigned char *oldi_buffer;
152 struct usb_endpoint_descriptor *interrupt_in_endpoint;
153 struct urb *interrupt_in_urb;
154 int interrupt_in_interval;
155 size_t interrupt_in_endpoint_size;
156 int interrupt_in_running;
157 int interrupt_in_done;
158
159 char *interrupt_out_buffer;
160 struct usb_endpoint_descriptor *interrupt_out_endpoint;
161 struct urb *interrupt_out_urb;
162 int interrupt_out_interval;
163 size_t interrupt_out_endpoint_size;
164 int interrupt_out_busy;
165
166 atomic_t writes_pending;
167 int event; /* alternate interface to events */
168 int fader; /* 10 bits */
169 int lights; /* 23 bits */
170 unsigned char dump_state; /* 0 if disabled 1 if enabled */
171 unsigned char enable; /* 0 if disabled 1 if enabled */
172 unsigned char offline; /* if the device is out of range or asleep */
173 unsigned char verbose; /* be verbose in error reporting */
174 unsigned char last_cmd[OUTPUT_CMD_SIZE];
175 unsigned char screen[32];
176 };
177
178 /* prevent races between open() and disconnect() */
179 static DEFINE_MUTEX(disconnect_mutex);
180
181 /* forward declaration */
182
183 static struct usb_driver usb_alphatrack_driver;
184
185 /**
186 * usb_alphatrack_abort_transfers
187 * aborts transfers and frees associated data structures
188 */
usb_alphatrack_abort_transfers(struct usb_alphatrack * dev)189 static void usb_alphatrack_abort_transfers(struct usb_alphatrack *dev)
190 {
191 /* shutdown transfer */
192 if (dev->interrupt_in_running) {
193 dev->interrupt_in_running = 0;
194 if (dev->intf)
195 usb_kill_urb(dev->interrupt_in_urb);
196 }
197 if (dev->interrupt_out_busy)
198 if (dev->intf)
199 usb_kill_urb(dev->interrupt_out_urb);
200 }
201
202 /**
203 * usb_alphatrack_delete
204 */
usb_alphatrack_delete(struct usb_alphatrack * dev)205 static void usb_alphatrack_delete(struct usb_alphatrack *dev)
206 {
207 usb_alphatrack_abort_transfers(dev);
208 usb_free_urb(dev->interrupt_in_urb);
209 usb_free_urb(dev->interrupt_out_urb);
210 kfree(dev->ring_buffer);
211 kfree(dev->interrupt_in_buffer);
212 kfree(dev->interrupt_out_buffer);
213 kfree(dev); /* fixme oldi_buffer */
214 }
215
216 /**
217 * usb_alphatrack_interrupt_in_callback
218 */
219
usb_alphatrack_interrupt_in_callback(struct urb * urb)220 static void usb_alphatrack_interrupt_in_callback(struct urb *urb)
221 {
222 struct usb_alphatrack *dev = urb->context;
223 unsigned int next_ring_head;
224 int retval = -1;
225
226 if (urb->status) {
227 if (urb->status == -ENOENT ||
228 urb->status == -ECONNRESET || urb->status == -ESHUTDOWN) {
229 goto exit;
230 } else {
231 dbg_info(&dev->intf->dev,
232 "%s: nonzero status received: %d\n", __func__,
233 urb->status);
234 goto resubmit; /* maybe we can recover */
235 }
236 }
237
238 if (urb->actual_length != INPUT_CMD_SIZE) {
239 dev_warn(&dev->intf->dev,
240 "Urb length was %d bytes!!"
241 "Do something intelligent\n", urb->actual_length);
242 } else {
243 alphatrack_ocmd_info(&dev->intf->dev,
244 &(*dev->ring_buffer)[dev->ring_tail].cmd,
245 "%s", "bla");
246 if (memcmp
247 (dev->interrupt_in_buffer, dev->oldi_buffer,
248 INPUT_CMD_SIZE) == 0) {
249 goto resubmit;
250 }
251 memcpy(dev->oldi_buffer, dev->interrupt_in_buffer,
252 INPUT_CMD_SIZE);
253
254 #if SUPPRESS_EXTRA_OFFLINE_EVENTS
255 if (dev->offline == 2 && dev->interrupt_in_buffer[1] == 0xff)
256 goto resubmit;
257 if (dev->offline == 1 && dev->interrupt_in_buffer[1] == 0xff) {
258 dev->offline = 2;
259 goto resubmit;
260 }
261 /* Always pass one offline event up the stack */
262 if (dev->offline > 0 && dev->interrupt_in_buffer[1] != 0xff)
263 dev->offline = 0;
264 if (dev->offline == 0 && dev->interrupt_in_buffer[1] == 0xff)
265 dev->offline = 1;
266 #endif
267 dbg_info(&dev->intf->dev, "%s: head, tail are %x, %x\n",
268 __func__, dev->ring_head, dev->ring_tail);
269 next_ring_head = (dev->ring_head + 1) % ring_buffer_size;
270
271 if (next_ring_head != dev->ring_tail) {
272 memcpy(&((*dev->ring_buffer)[dev->ring_head]),
273 dev->interrupt_in_buffer, urb->actual_length);
274 dev->ring_head = next_ring_head;
275 retval = 0;
276 memset(dev->interrupt_in_buffer, 0, urb->actual_length);
277 } else {
278 dev_warn(&dev->intf->dev,
279 "Ring buffer overflow, %d bytes dropped\n",
280 urb->actual_length);
281 memset(dev->interrupt_in_buffer, 0, urb->actual_length);
282 }
283 }
284
285 resubmit:
286 /* resubmit if we're still running */
287 if (dev->interrupt_in_running && dev->intf) {
288 retval = usb_submit_urb(dev->interrupt_in_urb, GFP_ATOMIC);
289 if (retval)
290 dev_err(&dev->intf->dev,
291 "usb_submit_urb failed (%d)\n", retval);
292 }
293
294 exit:
295 dev->interrupt_in_done = 1;
296 wake_up_interruptible(&dev->read_wait);
297 }
298
299 /**
300 * usb_alphatrack_interrupt_out_callback
301 */
usb_alphatrack_interrupt_out_callback(struct urb * urb)302 static void usb_alphatrack_interrupt_out_callback(struct urb *urb)
303 {
304 struct usb_alphatrack *dev = urb->context;
305
306 /* sync/async unlink faults aren't errors */
307 if (urb->status && !(urb->status == -ENOENT ||
308 urb->status == -ECONNRESET ||
309 urb->status == -ESHUTDOWN))
310 dbg_info(&dev->intf->dev,
311 "%s - nonzero write interrupt status received: %d\n",
312 __func__, urb->status);
313 atomic_dec(&dev->writes_pending);
314 dev->interrupt_out_busy = 0;
315 wake_up_interruptible(&dev->write_wait);
316 }
317
318 /**
319 * usb_alphatrack_open
320 */
usb_alphatrack_open(struct inode * inode,struct file * file)321 static int usb_alphatrack_open(struct inode *inode, struct file *file)
322 {
323 struct usb_alphatrack *dev;
324 int subminor;
325 int retval = 0;
326 struct usb_interface *interface;
327
328 nonseekable_open(inode, file);
329 subminor = iminor(inode);
330
331 mutex_lock(&disconnect_mutex);
332
333 interface = usb_find_interface(&usb_alphatrack_driver, subminor);
334
335 if (!interface) {
336 err("%s - error, can't find device for minor %d\n",
337 __func__, subminor);
338 retval = -ENODEV;
339 goto unlock_disconnect_exit;
340 }
341
342 dev = usb_get_intfdata(interface);
343
344 if (!dev) {
345 retval = -ENODEV;
346 goto unlock_disconnect_exit;
347 }
348
349 /* lock this device */
350 if (mutex_lock_interruptible(&dev->mtx)) {
351 retval = -ERESTARTSYS;
352 goto unlock_disconnect_exit;
353 }
354
355 /* allow opening only once */
356 if (dev->open_count) {
357 retval = -EBUSY;
358 goto unlock_exit;
359 }
360 dev->open_count = 1;
361
362 /* initialize in direction */
363 dev->ring_head = 0;
364 dev->ring_tail = 0;
365 usb_fill_int_urb(dev->interrupt_in_urb,
366 interface_to_usbdev(interface),
367 usb_rcvintpipe(interface_to_usbdev(interface),
368 dev->interrupt_in_endpoint->
369 bEndpointAddress),
370 dev->interrupt_in_buffer,
371 dev->interrupt_in_endpoint_size,
372 usb_alphatrack_interrupt_in_callback, dev,
373 dev->interrupt_in_interval);
374
375 dev->interrupt_in_running = 1;
376 dev->interrupt_in_done = 0;
377 dev->enable = 1;
378 dev->offline = 0;
379
380 retval = usb_submit_urb(dev->interrupt_in_urb, GFP_KERNEL);
381 if (retval) {
382 dev_err(&interface->dev,
383 "Couldn't submit interrupt_in_urb %d\n", retval);
384 dev->interrupt_in_running = 0;
385 dev->open_count = 0;
386 goto unlock_exit;
387 }
388
389 /* save device in the file's private structure */
390 file->private_data = dev;
391
392 unlock_exit:
393 mutex_unlock(&dev->mtx);
394
395 unlock_disconnect_exit:
396 mutex_unlock(&disconnect_mutex);
397
398 return retval;
399 }
400
401 /**
402 * usb_alphatrack_release
403 */
usb_alphatrack_release(struct inode * inode,struct file * file)404 static int usb_alphatrack_release(struct inode *inode, struct file *file)
405 {
406 struct usb_alphatrack *dev;
407 int retval = 0;
408
409 dev = file->private_data;
410
411 if (dev == NULL) {
412 retval = -ENODEV;
413 goto exit;
414 }
415
416 if (mutex_lock_interruptible(&dev->mtx)) {
417 retval = -ERESTARTSYS;
418 goto exit;
419 }
420
421 if (dev->open_count != 1) {
422 retval = -ENODEV;
423 goto unlock_exit;
424 }
425
426 if (dev->intf == NULL) {
427 /* the device was unplugged before the file was released */
428 mutex_unlock(&dev->mtx);
429 /* unlock here as usb_alphatrack_delete frees dev */
430 usb_alphatrack_delete(dev);
431 retval = -ENODEV;
432 goto exit;
433 }
434
435 /* wait until write transfer is finished */
436 if (dev->interrupt_out_busy)
437 wait_event_interruptible_timeout(dev->write_wait,
438 !dev->interrupt_out_busy,
439 2 * HZ);
440 usb_alphatrack_abort_transfers(dev);
441 dev->open_count = 0;
442
443 unlock_exit:
444 mutex_unlock(&dev->mtx);
445
446 exit:
447 return retval;
448 }
449
450 /**
451 * usb_alphatrack_poll
452 */
usb_alphatrack_poll(struct file * file,poll_table * wait)453 static unsigned int usb_alphatrack_poll(struct file *file, poll_table *wait)
454 {
455 struct usb_alphatrack *dev;
456 unsigned int mask = 0;
457
458 dev = file->private_data;
459
460 poll_wait(file, &dev->read_wait, wait);
461 poll_wait(file, &dev->write_wait, wait);
462
463 if (dev->ring_head != dev->ring_tail)
464 mask |= POLLIN | POLLRDNORM;
465 if (!dev->interrupt_out_busy)
466 mask |= POLLOUT | POLLWRNORM;
467
468 return mask;
469 }
470
471 /**
472 * usb_alphatrack_read
473 */
usb_alphatrack_read(struct file * file,char __user * buffer,size_t count,loff_t * ppos)474 static ssize_t usb_alphatrack_read(struct file *file, char __user *buffer,
475 size_t count, loff_t *ppos)
476 {
477 struct usb_alphatrack *dev;
478 int retval = 0;
479
480 int c = 0;
481
482 dev = file->private_data;
483
484 /* verify that we actually have some data to read */
485 if (count == 0)
486 goto exit;
487
488 /* lock this object */
489 if (mutex_lock_interruptible(&dev->mtx)) {
490 retval = -ERESTARTSYS;
491 goto exit;
492 }
493
494 /* verify that the device wasn't unplugged */
495 if (dev->intf == NULL) {
496 retval = -ENODEV;
497 err("No device or device unplugged %d\n", retval);
498 goto unlock_exit;
499 }
500
501 while (dev->ring_head == dev->ring_tail) {
502 if (file->f_flags & O_NONBLOCK) {
503 retval = -EAGAIN;
504 goto unlock_exit;
505 }
506 dev->interrupt_in_done = 0;
507 retval =
508 wait_event_interruptible(dev->read_wait,
509 dev->interrupt_in_done);
510 if (retval < 0)
511 goto unlock_exit;
512 }
513
514 alphatrack_ocmd_info(&dev->intf->dev,
515 &(*dev->ring_buffer)[dev->ring_tail].cmd, "%s",
516 ": copying to userspace");
517
518 c = 0;
519 while ((c < count) && (dev->ring_tail != dev->ring_head)) {
520 if (copy_to_user
521 (&buffer[c], &(*dev->ring_buffer)[dev->ring_tail],
522 INPUT_CMD_SIZE)) {
523 retval = -EFAULT;
524 goto unlock_exit;
525 }
526 dev->ring_tail = (dev->ring_tail + 1) % ring_buffer_size;
527 c += INPUT_CMD_SIZE;
528 dbg_info(&dev->intf->dev, "%s: head, tail are %x, %x\n",
529 __func__, dev->ring_head, dev->ring_tail);
530 }
531 retval = c;
532
533 unlock_exit:
534 /* unlock the device */
535 mutex_unlock(&dev->mtx);
536
537 exit:
538 return retval;
539 }
540
541 /**
542 * usb_alphatrack_write
543 */
usb_alphatrack_write(struct file * file,const char __user * buffer,size_t count,loff_t * ppos)544 static ssize_t usb_alphatrack_write(struct file *file,
545 const char __user *buffer, size_t count,
546 loff_t *ppos)
547 {
548 struct usb_alphatrack *dev;
549 size_t bytes_to_write;
550 int retval = 0;
551
552 dev = file->private_data;
553
554 /* verify that we actually have some data to write */
555 if (count == 0)
556 goto exit;
557
558 /* lock this object */
559 if (mutex_lock_interruptible(&dev->mtx)) {
560 retval = -ERESTARTSYS;
561 goto exit;
562 }
563
564 /* verify that the device wasn't unplugged */
565 if (dev->intf == NULL) {
566 retval = -ENODEV;
567 err("No device or device unplugged %d\n", retval);
568 goto unlock_exit;
569 }
570
571 /* wait until previous transfer is finished */
572 if (dev->interrupt_out_busy) {
573 if (file->f_flags & O_NONBLOCK) {
574 retval = -EAGAIN;
575 goto unlock_exit;
576 }
577 retval =
578 wait_event_interruptible(dev->write_wait,
579 !dev->interrupt_out_busy);
580 if (retval < 0)
581 goto unlock_exit;
582 }
583
584 /* write the data into interrupt_out_buffer from userspace */
585 /* FIXME - if you write more than 12 bytes this breaks */
586 bytes_to_write =
587 min(count, write_buffer_size * dev->interrupt_out_endpoint_size);
588 if (bytes_to_write < count)
589 dev_warn(&dev->intf->dev,
590 "Write buffer overflow, %zd bytes dropped\n",
591 count - bytes_to_write);
592
593 dbg_info(&dev->intf->dev, "%s: count = %zd, bytes_to_write = %zd\n",
594 __func__, count, bytes_to_write);
595
596 if (copy_from_user(dev->interrupt_out_buffer, buffer, bytes_to_write)) {
597 retval = -EFAULT;
598 goto unlock_exit;
599 }
600
601 if (dev->interrupt_out_endpoint == NULL) {
602 err("Endpoint should not be be null!\n");
603 goto unlock_exit;
604 }
605
606 /* send off the urb */
607 usb_fill_int_urb(dev->interrupt_out_urb,
608 interface_to_usbdev(dev->intf),
609 usb_sndintpipe(interface_to_usbdev(dev->intf),
610 dev->interrupt_out_endpoint->
611 bEndpointAddress),
612 dev->interrupt_out_buffer, bytes_to_write,
613 usb_alphatrack_interrupt_out_callback, dev,
614 dev->interrupt_out_interval);
615 dev->interrupt_out_busy = 1;
616 atomic_inc(&dev->writes_pending);
617 wmb();
618
619 retval = usb_submit_urb(dev->interrupt_out_urb, GFP_KERNEL);
620 if (retval) {
621 dev->interrupt_out_busy = 0;
622 err("Couldn't submit interrupt_out_urb %d\n", retval);
623 atomic_dec(&dev->writes_pending);
624 goto unlock_exit;
625 }
626 retval = bytes_to_write;
627
628 unlock_exit:
629 /* unlock the device */
630 mutex_unlock(&dev->mtx);
631
632 exit:
633 return retval;
634 }
635
636 /* file operations needed when we register this driver */
637 static const struct file_operations usb_alphatrack_fops = {
638 .owner = THIS_MODULE,
639 .read = usb_alphatrack_read,
640 .write = usb_alphatrack_write,
641 .open = usb_alphatrack_open,
642 .release = usb_alphatrack_release,
643 .poll = usb_alphatrack_poll,
644 .llseek = no_llseek,
645 };
646
647 /*
648 * usb class driver info in order to get a minor number from the usb core,
649 * and to have the device registered with the driver core
650 */
651
652 static struct usb_class_driver usb_alphatrack_class = {
653 .name = "alphatrack%d",
654 .fops = &usb_alphatrack_fops,
655 .minor_base = USB_ALPHATRACK_MINOR_BASE,
656 };
657
658 /**
659 * usb_alphatrack_probe
660 *
661 * Called by the usb core when a new device is connected that it thinks
662 * this driver might be interested in.
663 */
usb_alphatrack_probe(struct usb_interface * intf,const struct usb_device_id * id)664 static int usb_alphatrack_probe(struct usb_interface *intf,
665 const struct usb_device_id *id)
666 {
667 struct usb_device *udev = interface_to_usbdev(intf);
668 struct usb_alphatrack *dev = NULL;
669 struct usb_host_interface *iface_desc;
670 struct usb_endpoint_descriptor *endpoint;
671 int i;
672 int true_size;
673 int retval = -ENOMEM;
674
675 /* allocate memory for our device state and initialize it */
676
677 dev = kzalloc(sizeof(*dev), GFP_KERNEL);
678 if (dev == NULL) {
679 dev_err(&intf->dev, "Out of memory\n");
680 goto exit;
681 }
682 mutex_init(&dev->mtx);
683 dev->intf = intf;
684 init_waitqueue_head(&dev->read_wait);
685 init_waitqueue_head(&dev->write_wait);
686
687 iface_desc = intf->cur_altsetting;
688
689 /* set up the endpoint information */
690 for (i = 0; i < iface_desc->desc.bNumEndpoints; ++i) {
691 endpoint = &iface_desc->endpoint[i].desc;
692
693 if (usb_endpoint_is_int_in(endpoint))
694 dev->interrupt_in_endpoint = endpoint;
695
696 if (usb_endpoint_is_int_out(endpoint))
697 dev->interrupt_out_endpoint = endpoint;
698 }
699 if (dev->interrupt_in_endpoint == NULL) {
700 dev_err(&intf->dev, "Interrupt in endpoint not found\n");
701 goto error;
702 }
703 if (dev->interrupt_out_endpoint == NULL)
704 dev_warn(&intf->dev,
705 "Interrupt out endpoint not found"
706 "(using control endpoint instead)\n");
707
708 dev->interrupt_in_endpoint_size =
709 le16_to_cpu(dev->interrupt_in_endpoint->wMaxPacketSize);
710
711 if (dev->interrupt_in_endpoint_size != 64)
712 dev_warn(&intf->dev, "Interrupt in endpoint size is not 64!\n");
713
714 if (ring_buffer_size == 0)
715 ring_buffer_size = RING_BUFFER_SIZE;
716
717 true_size = min(ring_buffer_size, RING_BUFFER_SIZE);
718
719 /* FIXME - there are more usb_alloc routines for dma correctness.
720 Needed? */
721 dev->ring_buffer =
722 kmalloc((true_size * sizeof(struct alphatrack_icmd)), GFP_KERNEL);
723
724 if (!dev->ring_buffer) {
725 dev_err(&intf->dev,
726 "Couldn't allocate input ring_buffer of size %d\n",
727 true_size);
728 goto error;
729 }
730
731 dev->interrupt_in_buffer =
732 kmalloc(dev->interrupt_in_endpoint_size, GFP_KERNEL);
733
734 if (!dev->interrupt_in_buffer) {
735 dev_err(&intf->dev, "Couldn't allocate interrupt_in_buffer\n");
736 goto error;
737 }
738 dev->oldi_buffer = kmalloc(dev->interrupt_in_endpoint_size, GFP_KERNEL);
739 if (!dev->oldi_buffer) {
740 dev_err(&intf->dev, "Couldn't allocate old buffer\n");
741 goto error;
742 }
743 dev->interrupt_in_urb = usb_alloc_urb(0, GFP_KERNEL);
744 if (!dev->interrupt_in_urb) {
745 dev_err(&intf->dev, "Couldn't allocate interrupt_in_urb\n");
746 goto error;
747 }
748
749 dev->interrupt_out_endpoint_size =
750 dev->interrupt_out_endpoint ? le16_to_cpu(dev->
751 interrupt_out_endpoint->
752 wMaxPacketSize) : udev->
753 descriptor.bMaxPacketSize0;
754
755 if (dev->interrupt_out_endpoint_size != 64)
756 dev_warn(&intf->dev,
757 "Interrupt out endpoint size is not 64!)\n");
758
759 if (write_buffer_size == 0)
760 write_buffer_size = WRITE_BUFFER_SIZE;
761 true_size = min(write_buffer_size, WRITE_BUFFER_SIZE);
762
763 dev->interrupt_out_buffer =
764 kmalloc(true_size * dev->interrupt_out_endpoint_size, GFP_KERNEL);
765
766 if (!dev->interrupt_out_buffer) {
767 dev_err(&intf->dev, "Couldn't allocate interrupt_out_buffer\n");
768 goto error;
769 }
770
771 dev->write_buffer =
772 kmalloc(true_size * sizeof(struct alphatrack_ocmd), GFP_KERNEL);
773
774 if (!dev->write_buffer) {
775 dev_err(&intf->dev, "Couldn't allocate write_buffer\n");
776 goto error;
777 }
778
779 dev->interrupt_out_urb = usb_alloc_urb(0, GFP_KERNEL);
780 if (!dev->interrupt_out_urb) {
781 dev_err(&intf->dev, "Couldn't allocate interrupt_out_urb\n");
782 goto error;
783 }
784 dev->interrupt_in_interval =
785 min_interrupt_in_interval >
786 dev->interrupt_in_endpoint->
787 bInterval ? min_interrupt_in_interval : dev->interrupt_in_endpoint->
788 bInterval;
789 if (dev->interrupt_out_endpoint)
790 dev->interrupt_out_interval =
791 min_interrupt_out_interval >
792 dev->interrupt_out_endpoint->
793 bInterval ? min_interrupt_out_interval : dev->
794 interrupt_out_endpoint->bInterval;
795
796 /* we can register the device now, as it is ready */
797 usb_set_intfdata(intf, dev);
798
799 atomic_set(&dev->writes_pending, 0);
800 retval = usb_register_dev(intf, &usb_alphatrack_class);
801 if (retval) {
802 /* something prevented us from registering this driver */
803 dev_err(&intf->dev,
804 "Not able to get a minor for this device.\n");
805 usb_set_intfdata(intf, NULL);
806 goto error;
807 }
808
809 /* let the user know what node this device is now attached to */
810 dev_info(&intf->dev,
811 "Alphatrack Device #%d now attached to major %d minor %d\n",
812 (intf->minor - USB_ALPHATRACK_MINOR_BASE), USB_MAJOR,
813 intf->minor);
814
815 exit:
816 return retval;
817
818 error:
819 usb_alphatrack_delete(dev);
820
821 return retval;
822 }
823
824 /**
825 * usb_alphatrack_disconnect
826 *
827 * Called by the usb core when the device is removed from the system.
828 */
usb_alphatrack_disconnect(struct usb_interface * intf)829 static void usb_alphatrack_disconnect(struct usb_interface *intf)
830 {
831 struct usb_alphatrack *dev;
832 int minor;
833
834 mutex_lock(&disconnect_mutex);
835
836 dev = usb_get_intfdata(intf);
837 usb_set_intfdata(intf, NULL);
838
839 mutex_lock(&dev->mtx);
840
841 minor = intf->minor;
842
843 /* give back our minor */
844 usb_deregister_dev(intf, &usb_alphatrack_class);
845
846 /* if the device is not opened, then we clean up right now */
847 if (!dev->open_count) {
848 mutex_unlock(&dev->mtx);
849 usb_alphatrack_delete(dev);
850 } else {
851 dev->intf = NULL;
852 mutex_unlock(&dev->mtx);
853 }
854
855 atomic_set(&dev->writes_pending, 0);
856 mutex_unlock(&disconnect_mutex);
857
858 dev_info(&intf->dev, "Alphatrack Surface #%d now disconnected\n",
859 (minor - USB_ALPHATRACK_MINOR_BASE));
860 }
861
862 /* usb specific object needed to register this driver with the usb subsystem */
863 static struct usb_driver usb_alphatrack_driver = {
864 .name = "alphatrack",
865 .probe = usb_alphatrack_probe,
866 .disconnect = usb_alphatrack_disconnect,
867 .id_table = usb_alphatrack_table,
868 };
869
870 module_usb_driver(usb_alphatrack_driver);
871