USB: replace remaining __FUNCTION__ occurrences
[linux-2.6.git] / drivers / usb / misc / ldusb.c
1 /**
2  * Generic USB driver for report based interrupt in/out devices
3  * like LD Didactic's USB devices. LD Didactic's USB devices are
4  * HID devices which do not use HID report definitons (they use
5  * raw interrupt in and our reports only for communication).
6  *
7  * This driver uses a ring buffer for time critical reading of
8  * interrupt in reports and provides read and write methods for
9  * raw interrupt reports (similar to the Windows HID driver).
10  * Devices based on the book USB COMPLETE by Jan Axelson may need
11  * such a compatibility to the Windows HID driver.
12  *
13  * Copyright (C) 2005 Michael Hund <mhund@ld-didactic.de>
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; either version 2 of
18  *      the License, or (at your option) any later version.
19  *
20  * Derived from Lego USB Tower driver
21  * Copyright (C) 2003 David Glance <advidgsf@sourceforge.net>
22  *               2001-2004 Juergen Stuber <starblue@users.sourceforge.net>
23  *
24  * V0.1  (mh) Initial version
25  * V0.11 (mh) Added raw support for HID 1.0 devices (no interrupt out endpoint)
26  * V0.12 (mh) Added kmalloc check for string buffer
27  * V0.13 (mh) Added support for LD X-Ray and Machine Test System
28  */
29
30 #include <linux/kernel.h>
31 #include <linux/errno.h>
32 #include <linux/init.h>
33 #include <linux/slab.h>
34 #include <linux/module.h>
35 #include <linux/mutex.h>
36
37 #include <asm/uaccess.h>
38 #include <linux/input.h>
39 #include <linux/usb.h>
40 #include <linux/poll.h>
41
42 /* Define these values to match your devices */
43 #define USB_VENDOR_ID_LD                0x0f11  /* USB Vendor ID of LD Didactic GmbH */
44 #define USB_DEVICE_ID_LD_CASSY          0x1000  /* USB Product ID of CASSY-S */
45 #define USB_DEVICE_ID_LD_POCKETCASSY    0x1010  /* USB Product ID of Pocket-CASSY */
46 #define USB_DEVICE_ID_LD_MOBILECASSY    0x1020  /* USB Product ID of Mobile-CASSY */
47 #define USB_DEVICE_ID_LD_JWM            0x1080  /* USB Product ID of Joule and Wattmeter */
48 #define USB_DEVICE_ID_LD_DMMP           0x1081  /* USB Product ID of Digital Multimeter P (reserved) */
49 #define USB_DEVICE_ID_LD_UMIP           0x1090  /* USB Product ID of UMI P */
50 #define USB_DEVICE_ID_LD_XRAY1          0x1100  /* USB Product ID of X-Ray Apparatus */
51 #define USB_DEVICE_ID_LD_XRAY2          0x1101  /* USB Product ID of X-Ray Apparatus */
52 #define USB_DEVICE_ID_LD_VIDEOCOM       0x1200  /* USB Product ID of VideoCom */
53 #define USB_DEVICE_ID_LD_COM3LAB        0x2000  /* USB Product ID of COM3LAB */
54 #define USB_DEVICE_ID_LD_TELEPORT       0x2010  /* USB Product ID of Terminal Adapter */
55 #define USB_DEVICE_ID_LD_NETWORKANALYSER 0x2020 /* USB Product ID of Network Analyser */
56 #define USB_DEVICE_ID_LD_POWERCONTROL   0x2030  /* USB Product ID of Converter Control Unit */
57 #define USB_DEVICE_ID_LD_MACHINETEST    0x2040  /* USB Product ID of Machine Test System */
58
59 #define USB_VENDOR_ID_VERNIER           0x08f7
60 #define USB_DEVICE_ID_VERNIER_LABPRO    0x0001
61 #define USB_DEVICE_ID_VERNIER_GOTEMP    0x0002
62 #define USB_DEVICE_ID_VERNIER_SKIP      0x0003
63 #define USB_DEVICE_ID_VERNIER_CYCLOPS   0x0004
64 #define USB_DEVICE_ID_VERNIER_LCSPEC    0x0006
65
66 #define USB_VENDOR_ID_MICROCHIP         0x04d8
67 #define USB_DEVICE_ID_PICDEM            0x000c
68
69 #ifdef CONFIG_USB_DYNAMIC_MINORS
70 #define USB_LD_MINOR_BASE       0
71 #else
72 #define USB_LD_MINOR_BASE       176
73 #endif
74
75 /* table of devices that work with this driver */
76 static struct usb_device_id ld_usb_table [] = {
77         { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_CASSY) },
78         { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_POCKETCASSY) },
79         { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_MOBILECASSY) },
80         { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_JWM) },
81         { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_DMMP) },
82         { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_UMIP) },
83         { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_XRAY1) },
84         { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_XRAY2) },
85         { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_VIDEOCOM) },
86         { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_COM3LAB) },
87         { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_TELEPORT) },
88         { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_NETWORKANALYSER) },
89         { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_POWERCONTROL) },
90         { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_MACHINETEST) },
91         { USB_DEVICE(USB_VENDOR_ID_VERNIER, USB_DEVICE_ID_VERNIER_LABPRO) },
92         { USB_DEVICE(USB_VENDOR_ID_VERNIER, USB_DEVICE_ID_VERNIER_GOTEMP) },
93         { USB_DEVICE(USB_VENDOR_ID_VERNIER, USB_DEVICE_ID_VERNIER_SKIP) },
94         { USB_DEVICE(USB_VENDOR_ID_VERNIER, USB_DEVICE_ID_VERNIER_CYCLOPS) },
95         { USB_DEVICE(USB_VENDOR_ID_MICROCHIP, USB_DEVICE_ID_PICDEM) },
96         { USB_DEVICE(USB_VENDOR_ID_VERNIER, USB_DEVICE_ID_VERNIER_LCSPEC) },
97         { }                                     /* Terminating entry */
98 };
99 MODULE_DEVICE_TABLE(usb, ld_usb_table);
100 MODULE_VERSION("V0.13");
101 MODULE_AUTHOR("Michael Hund <mhund@ld-didactic.de>");
102 MODULE_DESCRIPTION("LD USB Driver");
103 MODULE_LICENSE("GPL");
104 MODULE_SUPPORTED_DEVICE("LD USB Devices");
105
106 #ifdef CONFIG_USB_DEBUG
107         static int debug = 1;
108 #else
109         static int debug = 0;
110 #endif
111
112 /* Use our own dbg macro */
113 #define dbg_info(dev, format, arg...) do { if (debug) dev_info(dev , format , ## arg); } while (0)
114
115 /* Module parameters */
116 module_param(debug, int, S_IRUGO | S_IWUSR);
117 MODULE_PARM_DESC(debug, "Debug enabled or not");
118
119 /* All interrupt in transfers are collected in a ring buffer to
120  * avoid racing conditions and get better performance of the driver.
121  */
122 static int ring_buffer_size = 128;
123 module_param(ring_buffer_size, int, 0);
124 MODULE_PARM_DESC(ring_buffer_size, "Read ring buffer size in reports");
125
126 /* The write_buffer can contain more than one interrupt out transfer.
127  */
128 static int write_buffer_size = 10;
129 module_param(write_buffer_size, int, 0);
130 MODULE_PARM_DESC(write_buffer_size, "Write buffer size in reports");
131
132 /* As of kernel version 2.6.4 ehci-hcd uses an
133  * "only one interrupt transfer per frame" shortcut
134  * to simplify the scheduling of periodic transfers.
135  * This conflicts with our standard 1ms intervals for in and out URBs.
136  * We use default intervals of 2ms for in and 2ms for out transfers,
137  * which should be fast enough.
138  * Increase the interval to allow more devices that do interrupt transfers,
139  * or set to 1 to use the standard interval from the endpoint descriptors.
140  */
141 static int min_interrupt_in_interval = 2;
142 module_param(min_interrupt_in_interval, int, 0);
143 MODULE_PARM_DESC(min_interrupt_in_interval, "Minimum interrupt in interval in ms");
144
145 static int min_interrupt_out_interval = 2;
146 module_param(min_interrupt_out_interval, int, 0);
147 MODULE_PARM_DESC(min_interrupt_out_interval, "Minimum interrupt out interval in ms");
148
149 /* Structure to hold all of our device specific stuff */
150 struct ld_usb {
151         struct semaphore        sem;            /* locks this structure */
152         struct usb_interface*   intf;           /* save off the usb interface pointer */
153
154         int                     open_count;     /* number of times this port has been opened */
155
156         char*                   ring_buffer;
157         unsigned int            ring_head;
158         unsigned int            ring_tail;
159
160         wait_queue_head_t       read_wait;
161         wait_queue_head_t       write_wait;
162
163         char*                   interrupt_in_buffer;
164         struct usb_endpoint_descriptor* interrupt_in_endpoint;
165         struct urb*             interrupt_in_urb;
166         int                     interrupt_in_interval;
167         size_t                  interrupt_in_endpoint_size;
168         int                     interrupt_in_running;
169         int                     interrupt_in_done;
170         int                     buffer_overflow;
171         spinlock_t              rbsl;
172
173         char*                   interrupt_out_buffer;
174         struct usb_endpoint_descriptor* interrupt_out_endpoint;
175         struct urb*             interrupt_out_urb;
176         int                     interrupt_out_interval;
177         size_t                  interrupt_out_endpoint_size;
178         int                     interrupt_out_busy;
179 };
180
181 static struct usb_driver ld_usb_driver;
182
183 /**
184  *      ld_usb_abort_transfers
185  *      aborts transfers and frees associated data structures
186  */
187 static void ld_usb_abort_transfers(struct ld_usb *dev)
188 {
189         /* shutdown transfer */
190         if (dev->interrupt_in_running) {
191                 dev->interrupt_in_running = 0;
192                 if (dev->intf)
193                         usb_kill_urb(dev->interrupt_in_urb);
194         }
195         if (dev->interrupt_out_busy)
196                 if (dev->intf)
197                         usb_kill_urb(dev->interrupt_out_urb);
198 }
199
200 /**
201  *      ld_usb_delete
202  */
203 static void ld_usb_delete(struct ld_usb *dev)
204 {
205         ld_usb_abort_transfers(dev);
206
207         /* free data structures */
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);
214 }
215
216 /**
217  *      ld_usb_interrupt_in_callback
218  */
219 static void ld_usb_interrupt_in_callback(struct urb *urb)
220 {
221         struct ld_usb *dev = urb->context;
222         size_t *actual_buffer;
223         unsigned int next_ring_head;
224         int status = urb->status;
225         int retval;
226
227         if (status) {
228                 if (status == -ENOENT ||
229                     status == -ECONNRESET ||
230                     status == -ESHUTDOWN) {
231                         goto exit;
232                 } else {
233                         dbg_info(&dev->intf->dev, "%s: nonzero status received: %d\n",
234                                  __func__, status);
235                         spin_lock(&dev->rbsl);
236                         goto resubmit; /* maybe we can recover */
237                 }
238         }
239
240         spin_lock(&dev->rbsl);
241         if (urb->actual_length > 0) {
242                 next_ring_head = (dev->ring_head+1) % ring_buffer_size;
243                 if (next_ring_head != dev->ring_tail) {
244                         actual_buffer = (size_t*)(dev->ring_buffer + dev->ring_head*(sizeof(size_t)+dev->interrupt_in_endpoint_size));
245                         /* actual_buffer gets urb->actual_length + interrupt_in_buffer */
246                         *actual_buffer = urb->actual_length;
247                         memcpy(actual_buffer+1, dev->interrupt_in_buffer, urb->actual_length);
248                         dev->ring_head = next_ring_head;
249                         dbg_info(&dev->intf->dev, "%s: received %d bytes\n",
250                                  __func__, urb->actual_length);
251                 } else {
252                         dev_warn(&dev->intf->dev,
253                                  "Ring buffer overflow, %d bytes dropped\n",
254                                  urb->actual_length);
255                         dev->buffer_overflow = 1;
256                 }
257         }
258
259 resubmit:
260         /* resubmit if we're still running */
261         if (dev->interrupt_in_running && !dev->buffer_overflow && dev->intf) {
262                 retval = usb_submit_urb(dev->interrupt_in_urb, GFP_ATOMIC);
263                 if (retval) {
264                         dev_err(&dev->intf->dev,
265                                 "usb_submit_urb failed (%d)\n", retval);
266                         dev->buffer_overflow = 1;
267                 }
268         }
269         spin_unlock(&dev->rbsl);
270 exit:
271         dev->interrupt_in_done = 1;
272         wake_up_interruptible(&dev->read_wait);
273 }
274
275 /**
276  *      ld_usb_interrupt_out_callback
277  */
278 static void ld_usb_interrupt_out_callback(struct urb *urb)
279 {
280         struct ld_usb *dev = urb->context;
281         int status = urb->status;
282
283         /* sync/async unlink faults aren't errors */
284         if (status && !(status == -ENOENT ||
285                         status == -ECONNRESET ||
286                         status == -ESHUTDOWN))
287                 dbg_info(&dev->intf->dev,
288                          "%s - nonzero write interrupt status received: %d\n",
289                          __func__, status);
290
291         dev->interrupt_out_busy = 0;
292         wake_up_interruptible(&dev->write_wait);
293 }
294
295 /**
296  *      ld_usb_open
297  */
298 static int ld_usb_open(struct inode *inode, struct file *file)
299 {
300         struct ld_usb *dev;
301         int subminor;
302         int retval;
303         struct usb_interface *interface;
304
305         nonseekable_open(inode, file);
306         subminor = iminor(inode);
307
308         interface = usb_find_interface(&ld_usb_driver, subminor);
309
310         if (!interface) {
311                 err("%s - error, can't find device for minor %d\n",
312                      __func__, subminor);
313                 return -ENODEV;
314         }
315
316         dev = usb_get_intfdata(interface);
317
318         if (!dev)
319                 return -ENODEV;
320
321         /* lock this device */
322         if (down_interruptible(&dev->sem))
323                 return -ERESTARTSYS;
324
325         /* allow opening only once */
326         if (dev->open_count) {
327                 retval = -EBUSY;
328                 goto unlock_exit;
329         }
330         dev->open_count = 1;
331
332         /* initialize in direction */
333         dev->ring_head = 0;
334         dev->ring_tail = 0;
335         dev->buffer_overflow = 0;
336         usb_fill_int_urb(dev->interrupt_in_urb,
337                          interface_to_usbdev(interface),
338                          usb_rcvintpipe(interface_to_usbdev(interface),
339                                         dev->interrupt_in_endpoint->bEndpointAddress),
340                          dev->interrupt_in_buffer,
341                          dev->interrupt_in_endpoint_size,
342                          ld_usb_interrupt_in_callback,
343                          dev,
344                          dev->interrupt_in_interval);
345
346         dev->interrupt_in_running = 1;
347         dev->interrupt_in_done = 0;
348
349         retval = usb_submit_urb(dev->interrupt_in_urb, GFP_KERNEL);
350         if (retval) {
351                 dev_err(&interface->dev, "Couldn't submit interrupt_in_urb %d\n", retval);
352                 dev->interrupt_in_running = 0;
353                 dev->open_count = 0;
354                 goto unlock_exit;
355         }
356
357         /* save device in the file's private structure */
358         file->private_data = dev;
359
360 unlock_exit:
361         up(&dev->sem);
362
363         return retval;
364 }
365
366 /**
367  *      ld_usb_release
368  */
369 static int ld_usb_release(struct inode *inode, struct file *file)
370 {
371         struct ld_usb *dev;
372         int retval = 0;
373
374         dev = file->private_data;
375
376         if (dev == NULL) {
377                 retval = -ENODEV;
378                 goto exit;
379         }
380
381         if (down_interruptible(&dev->sem)) {
382                 retval = -ERESTARTSYS;
383                 goto exit;
384         }
385
386         if (dev->open_count != 1) {
387                 retval = -ENODEV;
388                 goto unlock_exit;
389         }
390         if (dev->intf == NULL) {
391                 /* the device was unplugged before the file was released */
392                 up(&dev->sem);
393                 /* unlock here as ld_usb_delete frees dev */
394                 ld_usb_delete(dev);
395                 goto exit;
396         }
397
398         /* wait until write transfer is finished */
399         if (dev->interrupt_out_busy)
400                 wait_event_interruptible_timeout(dev->write_wait, !dev->interrupt_out_busy, 2 * HZ);
401         ld_usb_abort_transfers(dev);
402         dev->open_count = 0;
403
404 unlock_exit:
405         up(&dev->sem);
406
407 exit:
408         return retval;
409 }
410
411 /**
412  *      ld_usb_poll
413  */
414 static unsigned int ld_usb_poll(struct file *file, poll_table *wait)
415 {
416         struct ld_usb *dev;
417         unsigned int mask = 0;
418
419         dev = file->private_data;
420
421         poll_wait(file, &dev->read_wait, wait);
422         poll_wait(file, &dev->write_wait, wait);
423
424         if (dev->ring_head != dev->ring_tail)
425                 mask |= POLLIN | POLLRDNORM;
426         if (!dev->interrupt_out_busy)
427                 mask |= POLLOUT | POLLWRNORM;
428
429         return mask;
430 }
431
432 /**
433  *      ld_usb_read
434  */
435 static ssize_t ld_usb_read(struct file *file, char __user *buffer, size_t count,
436                            loff_t *ppos)
437 {
438         struct ld_usb *dev;
439         size_t *actual_buffer;
440         size_t bytes_to_read;
441         int retval = 0;
442         int rv;
443
444         dev = file->private_data;
445
446         /* verify that we actually have some data to read */
447         if (count == 0)
448                 goto exit;
449
450         /* lock this object */
451         if (down_interruptible(&dev->sem)) {
452                 retval = -ERESTARTSYS;
453                 goto exit;
454         }
455
456         /* verify that the device wasn't unplugged */
457         if (dev->intf == NULL) {
458                 retval = -ENODEV;
459                 err("No device or device unplugged %d\n", retval);
460                 goto unlock_exit;
461         }
462
463         /* wait for data */
464         spin_lock_irq(&dev->rbsl);
465         if (dev->ring_head == dev->ring_tail) {
466                 dev->interrupt_in_done = 0;
467                 spin_unlock_irq(&dev->rbsl);
468                 if (file->f_flags & O_NONBLOCK) {
469                         retval = -EAGAIN;
470                         goto unlock_exit;
471                 }
472                 retval = wait_event_interruptible(dev->read_wait, dev->interrupt_in_done);
473                 if (retval < 0)
474                         goto unlock_exit;
475         } else {
476                 spin_unlock_irq(&dev->rbsl);
477         }
478
479         /* actual_buffer contains actual_length + interrupt_in_buffer */
480         actual_buffer = (size_t*)(dev->ring_buffer + dev->ring_tail*(sizeof(size_t)+dev->interrupt_in_endpoint_size));
481         bytes_to_read = min(count, *actual_buffer);
482         if (bytes_to_read < *actual_buffer)
483                 dev_warn(&dev->intf->dev, "Read buffer overflow, %zd bytes dropped\n",
484                          *actual_buffer-bytes_to_read);
485
486         /* copy one interrupt_in_buffer from ring_buffer into userspace */
487         if (copy_to_user(buffer, actual_buffer+1, bytes_to_read)) {
488                 retval = -EFAULT;
489                 goto unlock_exit;
490         }
491         dev->ring_tail = (dev->ring_tail+1) % ring_buffer_size;
492
493         retval = bytes_to_read;
494
495         spin_lock_irq(&dev->rbsl);
496         if (dev->buffer_overflow) {
497                 dev->buffer_overflow = 0;
498                 spin_unlock_irq(&dev->rbsl);
499                 rv = usb_submit_urb(dev->interrupt_in_urb, GFP_KERNEL);
500                 if (rv < 0)
501                         dev->buffer_overflow = 1;
502         } else {
503                 spin_unlock_irq(&dev->rbsl);
504         }
505
506 unlock_exit:
507         /* unlock the device */
508         up(&dev->sem);
509
510 exit:
511         return retval;
512 }
513
514 /**
515  *      ld_usb_write
516  */
517 static ssize_t ld_usb_write(struct file *file, const char __user *buffer,
518                             size_t count, loff_t *ppos)
519 {
520         struct ld_usb *dev;
521         size_t bytes_to_write;
522         int retval = 0;
523
524         dev = file->private_data;
525
526         /* verify that we actually have some data to write */
527         if (count == 0)
528                 goto exit;
529
530         /* lock this object */
531         if (down_interruptible(&dev->sem)) {
532                 retval = -ERESTARTSYS;
533                 goto exit;
534         }
535
536         /* verify that the device wasn't unplugged */
537         if (dev->intf == NULL) {
538                 retval = -ENODEV;
539                 err("No device or device unplugged %d\n", retval);
540                 goto unlock_exit;
541         }
542
543         /* wait until previous transfer is finished */
544         if (dev->interrupt_out_busy) {
545                 if (file->f_flags & O_NONBLOCK) {
546                         retval = -EAGAIN;
547                         goto unlock_exit;
548                 }
549                 retval = wait_event_interruptible(dev->write_wait, !dev->interrupt_out_busy);
550                 if (retval < 0) {
551                         goto unlock_exit;
552                 }
553         }
554
555         /* write the data into interrupt_out_buffer from userspace */
556         bytes_to_write = min(count, write_buffer_size*dev->interrupt_out_endpoint_size);
557         if (bytes_to_write < count)
558                 dev_warn(&dev->intf->dev, "Write buffer overflow, %zd bytes dropped\n",count-bytes_to_write);
559         dbg_info(&dev->intf->dev, "%s: count = %zd, bytes_to_write = %zd\n", __func__, count, bytes_to_write);
560
561         if (copy_from_user(dev->interrupt_out_buffer, buffer, bytes_to_write)) {
562                 retval = -EFAULT;
563                 goto unlock_exit;
564         }
565
566         if (dev->interrupt_out_endpoint == NULL) {
567                 /* try HID_REQ_SET_REPORT=9 on control_endpoint instead of interrupt_out_endpoint */
568                 retval = usb_control_msg(interface_to_usbdev(dev->intf),
569                                          usb_sndctrlpipe(interface_to_usbdev(dev->intf), 0),
570                                          9,
571                                          USB_TYPE_CLASS | USB_RECIP_INTERFACE | USB_DIR_OUT,
572                                          1 << 8, 0,
573                                          dev->interrupt_out_buffer,
574                                          bytes_to_write,
575                                          USB_CTRL_SET_TIMEOUT * HZ);
576                 if (retval < 0)
577                         err("Couldn't submit HID_REQ_SET_REPORT %d\n", retval);
578                 goto unlock_exit;
579         }
580
581         /* send off the urb */
582         usb_fill_int_urb(dev->interrupt_out_urb,
583                          interface_to_usbdev(dev->intf),
584                          usb_sndintpipe(interface_to_usbdev(dev->intf),
585                                         dev->interrupt_out_endpoint->bEndpointAddress),
586                          dev->interrupt_out_buffer,
587                          bytes_to_write,
588                          ld_usb_interrupt_out_callback,
589                          dev,
590                          dev->interrupt_out_interval);
591
592         dev->interrupt_out_busy = 1;
593         wmb();
594
595         retval = usb_submit_urb(dev->interrupt_out_urb, GFP_KERNEL);
596         if (retval) {
597                 dev->interrupt_out_busy = 0;
598                 err("Couldn't submit interrupt_out_urb %d\n", retval);
599                 goto unlock_exit;
600         }
601         retval = bytes_to_write;
602
603 unlock_exit:
604         /* unlock the device */
605         up(&dev->sem);
606
607 exit:
608         return retval;
609 }
610
611 /* file operations needed when we register this driver */
612 static const struct file_operations ld_usb_fops = {
613         .owner =        THIS_MODULE,
614         .read  =        ld_usb_read,
615         .write =        ld_usb_write,
616         .open =         ld_usb_open,
617         .release =      ld_usb_release,
618         .poll =         ld_usb_poll,
619 };
620
621 /*
622  * usb class driver info in order to get a minor number from the usb core,
623  * and to have the device registered with the driver core
624  */
625 static struct usb_class_driver ld_usb_class = {
626         .name =         "ldusb%d",
627         .fops =         &ld_usb_fops,
628         .minor_base =   USB_LD_MINOR_BASE,
629 };
630
631 /**
632  *      ld_usb_probe
633  *
634  *      Called by the usb core when a new device is connected that it thinks
635  *      this driver might be interested in.
636  */
637 static int ld_usb_probe(struct usb_interface *intf, const struct usb_device_id *id)
638 {
639         struct usb_device *udev = interface_to_usbdev(intf);
640         struct ld_usb *dev = NULL;
641         struct usb_host_interface *iface_desc;
642         struct usb_endpoint_descriptor *endpoint;
643         char *buffer;
644         int i;
645         int retval = -ENOMEM;
646
647         /* allocate memory for our device state and intialize it */
648
649         dev = kzalloc(sizeof(*dev), GFP_KERNEL);
650         if (dev == NULL) {
651                 dev_err(&intf->dev, "Out of memory\n");
652                 goto exit;
653         }
654         init_MUTEX(&dev->sem);
655         spin_lock_init(&dev->rbsl);
656         dev->intf = intf;
657         init_waitqueue_head(&dev->read_wait);
658         init_waitqueue_head(&dev->write_wait);
659
660         /* workaround for early firmware versions on fast computers */
661         if ((le16_to_cpu(udev->descriptor.idVendor) == USB_VENDOR_ID_LD) &&
662             ((le16_to_cpu(udev->descriptor.idProduct) == USB_DEVICE_ID_LD_CASSY) ||
663              (le16_to_cpu(udev->descriptor.idProduct) == USB_DEVICE_ID_LD_COM3LAB)) &&
664             (le16_to_cpu(udev->descriptor.bcdDevice) <= 0x103)) {
665                 buffer = kmalloc(256, GFP_KERNEL);
666                 if (buffer == NULL) {
667                         dev_err(&intf->dev, "Couldn't allocate string buffer\n");
668                         goto error;
669                 }
670                 /* usb_string makes SETUP+STALL to leave always ControlReadLoop */
671                 usb_string(udev, 255, buffer, 256);
672                 kfree(buffer);
673         }
674
675         iface_desc = intf->cur_altsetting;
676
677         /* set up the endpoint information */
678         for (i = 0; i < iface_desc->desc.bNumEndpoints; ++i) {
679                 endpoint = &iface_desc->endpoint[i].desc;
680
681                 if (usb_endpoint_is_int_in(endpoint))
682                         dev->interrupt_in_endpoint = endpoint;
683
684                 if (usb_endpoint_is_int_out(endpoint))
685                         dev->interrupt_out_endpoint = endpoint;
686         }
687         if (dev->interrupt_in_endpoint == NULL) {
688                 dev_err(&intf->dev, "Interrupt in endpoint not found\n");
689                 goto error;
690         }
691         if (dev->interrupt_out_endpoint == NULL)
692                 dev_warn(&intf->dev, "Interrupt out endpoint not found (using control endpoint instead)\n");
693
694         dev->interrupt_in_endpoint_size = le16_to_cpu(dev->interrupt_in_endpoint->wMaxPacketSize);
695         dev->ring_buffer = kmalloc(ring_buffer_size*(sizeof(size_t)+dev->interrupt_in_endpoint_size), GFP_KERNEL);
696         if (!dev->ring_buffer) {
697                 dev_err(&intf->dev, "Couldn't allocate ring_buffer\n");
698                 goto error;
699         }
700         dev->interrupt_in_buffer = kmalloc(dev->interrupt_in_endpoint_size, GFP_KERNEL);
701         if (!dev->interrupt_in_buffer) {
702                 dev_err(&intf->dev, "Couldn't allocate interrupt_in_buffer\n");
703                 goto error;
704         }
705         dev->interrupt_in_urb = usb_alloc_urb(0, GFP_KERNEL);
706         if (!dev->interrupt_in_urb) {
707                 dev_err(&intf->dev, "Couldn't allocate interrupt_in_urb\n");
708                 goto error;
709         }
710         dev->interrupt_out_endpoint_size = dev->interrupt_out_endpoint ? le16_to_cpu(dev->interrupt_out_endpoint->wMaxPacketSize) :
711                                                                          udev->descriptor.bMaxPacketSize0;
712         dev->interrupt_out_buffer = kmalloc(write_buffer_size*dev->interrupt_out_endpoint_size, GFP_KERNEL);
713         if (!dev->interrupt_out_buffer) {
714                 dev_err(&intf->dev, "Couldn't allocate interrupt_out_buffer\n");
715                 goto error;
716         }
717         dev->interrupt_out_urb = usb_alloc_urb(0, GFP_KERNEL);
718         if (!dev->interrupt_out_urb) {
719                 dev_err(&intf->dev, "Couldn't allocate interrupt_out_urb\n");
720                 goto error;
721         }
722         dev->interrupt_in_interval = min_interrupt_in_interval > dev->interrupt_in_endpoint->bInterval ? min_interrupt_in_interval : dev->interrupt_in_endpoint->bInterval;
723         if (dev->interrupt_out_endpoint)
724                 dev->interrupt_out_interval = min_interrupt_out_interval > dev->interrupt_out_endpoint->bInterval ? min_interrupt_out_interval : dev->interrupt_out_endpoint->bInterval;
725
726         /* we can register the device now, as it is ready */
727         usb_set_intfdata(intf, dev);
728
729         retval = usb_register_dev(intf, &ld_usb_class);
730         if (retval) {
731                 /* something prevented us from registering this driver */
732                 dev_err(&intf->dev, "Not able to get a minor for this device.\n");
733                 usb_set_intfdata(intf, NULL);
734                 goto error;
735         }
736
737         /* let the user know what node this device is now attached to */
738         dev_info(&intf->dev, "LD USB Device #%d now attached to major %d minor %d\n",
739                 (intf->minor - USB_LD_MINOR_BASE), USB_MAJOR, intf->minor);
740
741 exit:
742         return retval;
743
744 error:
745         ld_usb_delete(dev);
746
747         return retval;
748 }
749
750 /**
751  *      ld_usb_disconnect
752  *
753  *      Called by the usb core when the device is removed from the system.
754  */
755 static void ld_usb_disconnect(struct usb_interface *intf)
756 {
757         struct ld_usb *dev;
758         int minor;
759
760         dev = usb_get_intfdata(intf);
761         usb_set_intfdata(intf, NULL);
762
763         minor = intf->minor;
764
765         /* give back our minor */
766         usb_deregister_dev(intf, &ld_usb_class);
767
768         down(&dev->sem);
769
770         /* if the device is not opened, then we clean up right now */
771         if (!dev->open_count) {
772                 up(&dev->sem);
773                 ld_usb_delete(dev);
774         } else {
775                 dev->intf = NULL;
776                 up(&dev->sem);
777         }
778
779         dev_info(&intf->dev, "LD USB Device #%d now disconnected\n",
780                  (minor - USB_LD_MINOR_BASE));
781 }
782
783 /* usb specific object needed to register this driver with the usb subsystem */
784 static struct usb_driver ld_usb_driver = {
785         .name =         "ldusb",
786         .probe =        ld_usb_probe,
787         .disconnect =   ld_usb_disconnect,
788         .id_table =     ld_usb_table,
789 };
790
791 /**
792  *      ld_usb_init
793  */
794 static int __init ld_usb_init(void)
795 {
796         int retval;
797
798         /* register this driver with the USB subsystem */
799         retval = usb_register(&ld_usb_driver);
800         if (retval)
801                 err("usb_register failed for the "__FILE__" driver. Error number %d\n", retval);
802
803         return retval;
804 }
805
806 /**
807  *      ld_usb_exit
808  */
809 static void __exit ld_usb_exit(void)
810 {
811         /* deregister this driver with the USB subsystem */
812         usb_deregister(&ld_usb_driver);
813 }
814
815 module_init(ld_usb_init);
816 module_exit(ld_usb_exit);
817