USB: Make file operations structs in drivers/usb const.
[linux-3.10.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
65
66 #ifdef CONFIG_USB_DYNAMIC_MINORS
67 #define USB_LD_MINOR_BASE       0
68 #else
69 #define USB_LD_MINOR_BASE       176
70 #endif
71
72 /* table of devices that work with this driver */
73 static struct usb_device_id ld_usb_table [] = {
74         { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_CASSY) },
75         { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_POCKETCASSY) },
76         { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_MOBILECASSY) },
77         { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_JWM) },
78         { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_DMMP) },
79         { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_UMIP) },
80         { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_XRAY1) },
81         { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_XRAY2) },
82         { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_VIDEOCOM) },
83         { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_COM3LAB) },
84         { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_TELEPORT) },
85         { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_NETWORKANALYSER) },
86         { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_POWERCONTROL) },
87         { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_MACHINETEST) },
88         { USB_DEVICE(USB_VENDOR_ID_VERNIER, USB_DEVICE_ID_VERNIER_LABPRO) },
89         { USB_DEVICE(USB_VENDOR_ID_VERNIER, USB_DEVICE_ID_VERNIER_GOTEMP) },
90         { USB_DEVICE(USB_VENDOR_ID_VERNIER, USB_DEVICE_ID_VERNIER_SKIP) },
91         { USB_DEVICE(USB_VENDOR_ID_VERNIER, USB_DEVICE_ID_VERNIER_CYCLOPS) },
92         { }                                     /* Terminating entry */
93 };
94 MODULE_DEVICE_TABLE(usb, ld_usb_table);
95 MODULE_VERSION("V0.13");
96 MODULE_AUTHOR("Michael Hund <mhund@ld-didactic.de>");
97 MODULE_DESCRIPTION("LD USB Driver");
98 MODULE_LICENSE("GPL");
99 MODULE_SUPPORTED_DEVICE("LD USB Devices");
100
101 #ifdef CONFIG_USB_DEBUG
102         static int debug = 1;
103 #else
104         static int debug = 0;
105 #endif
106
107 /* Use our own dbg macro */
108 #define dbg_info(dev, format, arg...) do { if (debug) dev_info(dev , format , ## arg); } while (0)
109
110 /* Module parameters */
111 module_param(debug, int, S_IRUGO | S_IWUSR);
112 MODULE_PARM_DESC(debug, "Debug enabled or not");
113
114 /* All interrupt in transfers are collected in a ring buffer to
115  * avoid racing conditions and get better performance of the driver.
116  */
117 static int ring_buffer_size = 128;
118 module_param(ring_buffer_size, int, 0);
119 MODULE_PARM_DESC(ring_buffer_size, "Read ring buffer size in reports");
120
121 /* The write_buffer can contain more than one interrupt out transfer.
122  */
123 static int write_buffer_size = 10;
124 module_param(write_buffer_size, int, 0);
125 MODULE_PARM_DESC(write_buffer_size, "Write buffer size in reports");
126
127 /* As of kernel version 2.6.4 ehci-hcd uses an
128  * "only one interrupt transfer per frame" shortcut
129  * to simplify the scheduling of periodic transfers.
130  * This conflicts with our standard 1ms intervals for in and out URBs.
131  * We use default intervals of 2ms for in and 2ms for out transfers,
132  * which should be fast enough.
133  * Increase the interval to allow more devices that do interrupt transfers,
134  * or set to 1 to use the standard interval from the endpoint descriptors.
135  */
136 static int min_interrupt_in_interval = 2;
137 module_param(min_interrupt_in_interval, int, 0);
138 MODULE_PARM_DESC(min_interrupt_in_interval, "Minimum interrupt in interval in ms");
139
140 static int min_interrupt_out_interval = 2;
141 module_param(min_interrupt_out_interval, int, 0);
142 MODULE_PARM_DESC(min_interrupt_out_interval, "Minimum interrupt out interval in ms");
143
144 /* Structure to hold all of our device specific stuff */
145 struct ld_usb {
146         struct semaphore        sem;            /* locks this structure */
147         struct usb_interface*   intf;           /* save off the usb interface pointer */
148
149         int                     open_count;     /* number of times this port has been opened */
150
151         char*                   ring_buffer;
152         unsigned int            ring_head;
153         unsigned int            ring_tail;
154
155         wait_queue_head_t       read_wait;
156         wait_queue_head_t       write_wait;
157
158         char*                   interrupt_in_buffer;
159         struct usb_endpoint_descriptor* interrupt_in_endpoint;
160         struct urb*             interrupt_in_urb;
161         int                     interrupt_in_interval;
162         size_t                  interrupt_in_endpoint_size;
163         int                     interrupt_in_running;
164         int                     interrupt_in_done;
165
166         char*                   interrupt_out_buffer;
167         struct usb_endpoint_descriptor* interrupt_out_endpoint;
168         struct urb*             interrupt_out_urb;
169         int                     interrupt_out_interval;
170         size_t                  interrupt_out_endpoint_size;
171         int                     interrupt_out_busy;
172 };
173
174 /* prevent races between open() and disconnect() */
175 static DEFINE_MUTEX(disconnect_mutex);
176
177 static struct usb_driver ld_usb_driver;
178
179 /**
180  *      ld_usb_abort_transfers
181  *      aborts transfers and frees associated data structures
182  */
183 static void ld_usb_abort_transfers(struct ld_usb *dev)
184 {
185         /* shutdown transfer */
186         if (dev->interrupt_in_running) {
187                 dev->interrupt_in_running = 0;
188                 if (dev->intf)
189                         usb_kill_urb(dev->interrupt_in_urb);
190         }
191         if (dev->interrupt_out_busy)
192                 if (dev->intf)
193                         usb_kill_urb(dev->interrupt_out_urb);
194 }
195
196 /**
197  *      ld_usb_delete
198  */
199 static void ld_usb_delete(struct ld_usb *dev)
200 {
201         ld_usb_abort_transfers(dev);
202
203         /* free data structures */
204         usb_free_urb(dev->interrupt_in_urb);
205         usb_free_urb(dev->interrupt_out_urb);
206         kfree(dev->ring_buffer);
207         kfree(dev->interrupt_in_buffer);
208         kfree(dev->interrupt_out_buffer);
209         kfree(dev);
210 }
211
212 /**
213  *      ld_usb_interrupt_in_callback
214  */
215 static void ld_usb_interrupt_in_callback(struct urb *urb, struct pt_regs *regs)
216 {
217         struct ld_usb *dev = urb->context;
218         size_t *actual_buffer;
219         unsigned int next_ring_head;
220         int retval;
221
222         if (urb->status) {
223                 if (urb->status == -ENOENT ||
224                     urb->status == -ECONNRESET ||
225                     urb->status == -ESHUTDOWN) {
226                         goto exit;
227                 } else {
228                         dbg_info(&dev->intf->dev, "%s: nonzero status received: %d\n",
229                                  __FUNCTION__, urb->status);
230                         goto resubmit; /* maybe we can recover */
231                 }
232         }
233
234         if (urb->actual_length > 0) {
235                 next_ring_head = (dev->ring_head+1) % ring_buffer_size;
236                 if (next_ring_head != dev->ring_tail) {
237                         actual_buffer = (size_t*)(dev->ring_buffer + dev->ring_head*(sizeof(size_t)+dev->interrupt_in_endpoint_size));
238                         /* actual_buffer gets urb->actual_length + interrupt_in_buffer */
239                         *actual_buffer = urb->actual_length;
240                         memcpy(actual_buffer+1, dev->interrupt_in_buffer, urb->actual_length);
241                         dev->ring_head = next_ring_head;
242                         dbg_info(&dev->intf->dev, "%s: received %d bytes\n",
243                                  __FUNCTION__, urb->actual_length);
244                 } else
245                         dev_warn(&dev->intf->dev,
246                                  "Ring buffer overflow, %d bytes dropped\n",
247                                  urb->actual_length);
248         }
249
250 resubmit:
251         /* resubmit if we're still running */
252         if (dev->interrupt_in_running && dev->intf) {
253                 retval = usb_submit_urb(dev->interrupt_in_urb, GFP_ATOMIC);
254                 if (retval)
255                         dev_err(&dev->intf->dev,
256                                 "usb_submit_urb failed (%d)\n", retval);
257         }
258
259 exit:
260         dev->interrupt_in_done = 1;
261         wake_up_interruptible(&dev->read_wait);
262 }
263
264 /**
265  *      ld_usb_interrupt_out_callback
266  */
267 static void ld_usb_interrupt_out_callback(struct urb *urb, struct pt_regs *regs)
268 {
269         struct ld_usb *dev = urb->context;
270
271         /* sync/async unlink faults aren't errors */
272         if (urb->status && !(urb->status == -ENOENT ||
273                              urb->status == -ECONNRESET ||
274                              urb->status == -ESHUTDOWN))
275                 dbg_info(&dev->intf->dev,
276                          "%s - nonzero write interrupt status received: %d\n",
277                          __FUNCTION__, urb->status);
278
279         dev->interrupt_out_busy = 0;
280         wake_up_interruptible(&dev->write_wait);
281 }
282
283 /**
284  *      ld_usb_open
285  */
286 static int ld_usb_open(struct inode *inode, struct file *file)
287 {
288         struct ld_usb *dev;
289         int subminor;
290         int retval = 0;
291         struct usb_interface *interface;
292
293         nonseekable_open(inode, file);
294         subminor = iminor(inode);
295
296         mutex_lock(&disconnect_mutex);
297
298         interface = usb_find_interface(&ld_usb_driver, subminor);
299
300         if (!interface) {
301                 err("%s - error, can't find device for minor %d\n",
302                      __FUNCTION__, subminor);
303                 retval = -ENODEV;
304                 goto unlock_disconnect_exit;
305         }
306
307         dev = usb_get_intfdata(interface);
308
309         if (!dev) {
310                 retval = -ENODEV;
311                 goto unlock_disconnect_exit;
312         }
313
314         /* lock this device */
315         if (down_interruptible(&dev->sem)) {
316                 retval = -ERESTARTSYS;
317                 goto unlock_disconnect_exit;
318         }
319
320         /* allow opening only once */
321         if (dev->open_count) {
322                 retval = -EBUSY;
323                 goto unlock_exit;
324         }
325         dev->open_count = 1;
326
327         /* initialize in direction */
328         dev->ring_head = 0;
329         dev->ring_tail = 0;
330         usb_fill_int_urb(dev->interrupt_in_urb,
331                          interface_to_usbdev(interface),
332                          usb_rcvintpipe(interface_to_usbdev(interface),
333                                         dev->interrupt_in_endpoint->bEndpointAddress),
334                          dev->interrupt_in_buffer,
335                          dev->interrupt_in_endpoint_size,
336                          ld_usb_interrupt_in_callback,
337                          dev,
338                          dev->interrupt_in_interval);
339
340         dev->interrupt_in_running = 1;
341         dev->interrupt_in_done = 0;
342
343         retval = usb_submit_urb(dev->interrupt_in_urb, GFP_KERNEL);
344         if (retval) {
345                 dev_err(&interface->dev, "Couldn't submit interrupt_in_urb %d\n", retval);
346                 dev->interrupt_in_running = 0;
347                 dev->open_count = 0;
348                 goto unlock_exit;
349         }
350
351         /* save device in the file's private structure */
352         file->private_data = dev;
353
354 unlock_exit:
355         up(&dev->sem);
356
357 unlock_disconnect_exit:
358         mutex_unlock(&disconnect_mutex);
359
360         return retval;
361 }
362
363 /**
364  *      ld_usb_release
365  */
366 static int ld_usb_release(struct inode *inode, struct file *file)
367 {
368         struct ld_usb *dev;
369         int retval = 0;
370
371         dev = file->private_data;
372
373         if (dev == NULL) {
374                 retval = -ENODEV;
375                 goto exit;
376         }
377
378         if (down_interruptible(&dev->sem)) {
379                 retval = -ERESTARTSYS;
380                 goto exit;
381         }
382
383         if (dev->open_count != 1) {
384                 retval = -ENODEV;
385                 goto unlock_exit;
386         }
387         if (dev->intf == NULL) {
388                 /* the device was unplugged before the file was released */
389                 up(&dev->sem);
390                 /* unlock here as ld_usb_delete frees dev */
391                 ld_usb_delete(dev);
392                 goto exit;
393         }
394
395         /* wait until write transfer is finished */
396         if (dev->interrupt_out_busy)
397                 wait_event_interruptible_timeout(dev->write_wait, !dev->interrupt_out_busy, 2 * HZ);
398         ld_usb_abort_transfers(dev);
399         dev->open_count = 0;
400
401 unlock_exit:
402         up(&dev->sem);
403
404 exit:
405         return retval;
406 }
407
408 /**
409  *      ld_usb_poll
410  */
411 static unsigned int ld_usb_poll(struct file *file, poll_table *wait)
412 {
413         struct ld_usb *dev;
414         unsigned int mask = 0;
415
416         dev = file->private_data;
417
418         poll_wait(file, &dev->read_wait, wait);
419         poll_wait(file, &dev->write_wait, wait);
420
421         if (dev->ring_head != dev->ring_tail)
422                 mask |= POLLIN | POLLRDNORM;
423         if (!dev->interrupt_out_busy)
424                 mask |= POLLOUT | POLLWRNORM;
425
426         return mask;
427 }
428
429 /**
430  *      ld_usb_read
431  */
432 static ssize_t ld_usb_read(struct file *file, char __user *buffer, size_t count,
433                            loff_t *ppos)
434 {
435         struct ld_usb *dev;
436         size_t *actual_buffer;
437         size_t bytes_to_read;
438         int retval = 0;
439
440         dev = file->private_data;
441
442         /* verify that we actually have some data to read */
443         if (count == 0)
444                 goto exit;
445
446         /* lock this object */
447         if (down_interruptible(&dev->sem)) {
448                 retval = -ERESTARTSYS;
449                 goto exit;
450         }
451
452         /* verify that the device wasn't unplugged */
453         if (dev->intf == NULL) {
454                 retval = -ENODEV;
455                 err("No device or device unplugged %d\n", retval);
456                 goto unlock_exit;
457         }
458
459         /* wait for data */
460         if (dev->ring_head == dev->ring_tail) {
461                 if (file->f_flags & O_NONBLOCK) {
462                         retval = -EAGAIN;
463                         goto unlock_exit;
464                 }
465                 retval = wait_event_interruptible(dev->read_wait, dev->interrupt_in_done);
466                 if (retval < 0)
467                         goto unlock_exit;
468         }
469
470         /* actual_buffer contains actual_length + interrupt_in_buffer */
471         actual_buffer = (size_t*)(dev->ring_buffer + dev->ring_tail*(sizeof(size_t)+dev->interrupt_in_endpoint_size));
472         bytes_to_read = min(count, *actual_buffer);
473         if (bytes_to_read < *actual_buffer)
474                 dev_warn(&dev->intf->dev, "Read buffer overflow, %zd bytes dropped\n",
475                          *actual_buffer-bytes_to_read);
476
477         /* copy one interrupt_in_buffer from ring_buffer into userspace */
478         if (copy_to_user(buffer, actual_buffer+1, bytes_to_read)) {
479                 retval = -EFAULT;
480                 goto unlock_exit;
481         }
482         dev->ring_tail = (dev->ring_tail+1) % ring_buffer_size;
483
484         retval = bytes_to_read;
485
486 unlock_exit:
487         /* unlock the device */
488         up(&dev->sem);
489
490 exit:
491         return retval;
492 }
493
494 /**
495  *      ld_usb_write
496  */
497 static ssize_t ld_usb_write(struct file *file, const char __user *buffer,
498                             size_t count, loff_t *ppos)
499 {
500         struct ld_usb *dev;
501         size_t bytes_to_write;
502         int retval = 0;
503
504         dev = file->private_data;
505
506         /* verify that we actually have some data to write */
507         if (count == 0)
508                 goto exit;
509
510         /* lock this object */
511         if (down_interruptible(&dev->sem)) {
512                 retval = -ERESTARTSYS;
513                 goto exit;
514         }
515
516         /* verify that the device wasn't unplugged */
517         if (dev->intf == NULL) {
518                 retval = -ENODEV;
519                 err("No device or device unplugged %d\n", retval);
520                 goto unlock_exit;
521         }
522
523         /* wait until previous transfer is finished */
524         if (dev->interrupt_out_busy) {
525                 if (file->f_flags & O_NONBLOCK) {
526                         retval = -EAGAIN;
527                         goto unlock_exit;
528                 }
529                 retval = wait_event_interruptible(dev->write_wait, !dev->interrupt_out_busy);
530                 if (retval < 0) {
531                         goto unlock_exit;
532                 }
533         }
534
535         /* write the data into interrupt_out_buffer from userspace */
536         bytes_to_write = min(count, write_buffer_size*dev->interrupt_out_endpoint_size);
537         if (bytes_to_write < count)
538                 dev_warn(&dev->intf->dev, "Write buffer overflow, %zd bytes dropped\n",count-bytes_to_write);
539         dbg_info(&dev->intf->dev, "%s: count = %zd, bytes_to_write = %zd\n", __FUNCTION__, count, bytes_to_write);
540
541         if (copy_from_user(dev->interrupt_out_buffer, buffer, bytes_to_write)) {
542                 retval = -EFAULT;
543                 goto unlock_exit;
544         }
545
546         if (dev->interrupt_out_endpoint == NULL) {
547                 /* try HID_REQ_SET_REPORT=9 on control_endpoint instead of interrupt_out_endpoint */
548                 retval = usb_control_msg(interface_to_usbdev(dev->intf),
549                                          usb_sndctrlpipe(interface_to_usbdev(dev->intf), 0),
550                                          9,
551                                          USB_TYPE_CLASS | USB_RECIP_INTERFACE | USB_DIR_OUT,
552                                          1 << 8, 0,
553                                          dev->interrupt_out_buffer,
554                                          bytes_to_write,
555                                          USB_CTRL_SET_TIMEOUT * HZ);
556                 if (retval < 0)
557                         err("Couldn't submit HID_REQ_SET_REPORT %d\n", retval);
558                 goto unlock_exit;
559         }
560
561         /* send off the urb */
562         usb_fill_int_urb(dev->interrupt_out_urb,
563                          interface_to_usbdev(dev->intf),
564                          usb_sndintpipe(interface_to_usbdev(dev->intf),
565                                         dev->interrupt_out_endpoint->bEndpointAddress),
566                          dev->interrupt_out_buffer,
567                          bytes_to_write,
568                          ld_usb_interrupt_out_callback,
569                          dev,
570                          dev->interrupt_out_interval);
571
572         dev->interrupt_out_busy = 1;
573         wmb();
574
575         retval = usb_submit_urb(dev->interrupt_out_urb, GFP_KERNEL);
576         if (retval) {
577                 dev->interrupt_out_busy = 0;
578                 err("Couldn't submit interrupt_out_urb %d\n", retval);
579                 goto unlock_exit;
580         }
581         retval = bytes_to_write;
582
583 unlock_exit:
584         /* unlock the device */
585         up(&dev->sem);
586
587 exit:
588         return retval;
589 }
590
591 /* file operations needed when we register this driver */
592 static const struct file_operations ld_usb_fops = {
593         .owner =        THIS_MODULE,
594         .read  =        ld_usb_read,
595         .write =        ld_usb_write,
596         .open =         ld_usb_open,
597         .release =      ld_usb_release,
598         .poll =         ld_usb_poll,
599 };
600
601 /*
602  * usb class driver info in order to get a minor number from the usb core,
603  * and to have the device registered with the driver core
604  */
605 static struct usb_class_driver ld_usb_class = {
606         .name =         "ldusb%d",
607         .fops =         &ld_usb_fops,
608         .minor_base =   USB_LD_MINOR_BASE,
609 };
610
611 /**
612  *      ld_usb_probe
613  *
614  *      Called by the usb core when a new device is connected that it thinks
615  *      this driver might be interested in.
616  */
617 static int ld_usb_probe(struct usb_interface *intf, const struct usb_device_id *id)
618 {
619         struct usb_device *udev = interface_to_usbdev(intf);
620         struct ld_usb *dev = NULL;
621         struct usb_host_interface *iface_desc;
622         struct usb_endpoint_descriptor *endpoint;
623         char *buffer;
624         int i;
625         int retval = -ENOMEM;
626
627         /* allocate memory for our device state and intialize it */
628
629         dev = kzalloc(sizeof(*dev), GFP_KERNEL);
630         if (dev == NULL) {
631                 dev_err(&intf->dev, "Out of memory\n");
632                 goto exit;
633         }
634         init_MUTEX(&dev->sem);
635         dev->intf = intf;
636         init_waitqueue_head(&dev->read_wait);
637         init_waitqueue_head(&dev->write_wait);
638
639         /* workaround for early firmware versions on fast computers */
640         if ((le16_to_cpu(udev->descriptor.idVendor) == USB_VENDOR_ID_LD) &&
641             ((le16_to_cpu(udev->descriptor.idProduct) == USB_DEVICE_ID_LD_CASSY) ||
642              (le16_to_cpu(udev->descriptor.idProduct) == USB_DEVICE_ID_LD_COM3LAB)) &&
643             (le16_to_cpu(udev->descriptor.bcdDevice) <= 0x103)) {
644                 buffer = kmalloc(256, GFP_KERNEL);
645                 if (buffer == NULL) {
646                         dev_err(&intf->dev, "Couldn't allocate string buffer\n");
647                         goto error;
648                 }
649                 /* usb_string makes SETUP+STALL to leave always ControlReadLoop */
650                 usb_string(udev, 255, buffer, 256);
651                 kfree(buffer);
652         }
653
654         iface_desc = intf->cur_altsetting;
655
656         /* set up the endpoint information */
657         for (i = 0; i < iface_desc->desc.bNumEndpoints; ++i) {
658                 endpoint = &iface_desc->endpoint[i].desc;
659
660                 if (((endpoint->bEndpointAddress & USB_ENDPOINT_DIR_MASK) == USB_DIR_IN) &&
661                     ((endpoint->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK) == USB_ENDPOINT_XFER_INT)) {
662                         dev->interrupt_in_endpoint = endpoint;
663                 }
664
665                 if (((endpoint->bEndpointAddress & USB_ENDPOINT_DIR_MASK) == USB_DIR_OUT) &&
666                     ((endpoint->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK) == USB_ENDPOINT_XFER_INT)) {
667                         dev->interrupt_out_endpoint = endpoint;
668                 }
669         }
670         if (dev->interrupt_in_endpoint == NULL) {
671                 dev_err(&intf->dev, "Interrupt in endpoint not found\n");
672                 goto error;
673         }
674         if (dev->interrupt_out_endpoint == NULL)
675                 dev_warn(&intf->dev, "Interrupt out endpoint not found (using control endpoint instead)\n");
676
677         dev->interrupt_in_endpoint_size = le16_to_cpu(dev->interrupt_in_endpoint->wMaxPacketSize);
678         dev->ring_buffer = kmalloc(ring_buffer_size*(sizeof(size_t)+dev->interrupt_in_endpoint_size), GFP_KERNEL);
679         if (!dev->ring_buffer) {
680                 dev_err(&intf->dev, "Couldn't allocate ring_buffer\n");
681                 goto error;
682         }
683         dev->interrupt_in_buffer = kmalloc(dev->interrupt_in_endpoint_size, GFP_KERNEL);
684         if (!dev->interrupt_in_buffer) {
685                 dev_err(&intf->dev, "Couldn't allocate interrupt_in_buffer\n");
686                 goto error;
687         }
688         dev->interrupt_in_urb = usb_alloc_urb(0, GFP_KERNEL);
689         if (!dev->interrupt_in_urb) {
690                 dev_err(&intf->dev, "Couldn't allocate interrupt_in_urb\n");
691                 goto error;
692         }
693         dev->interrupt_out_endpoint_size = dev->interrupt_out_endpoint ? le16_to_cpu(dev->interrupt_out_endpoint->wMaxPacketSize) :
694                                                                          udev->descriptor.bMaxPacketSize0;
695         dev->interrupt_out_buffer = kmalloc(write_buffer_size*dev->interrupt_out_endpoint_size, GFP_KERNEL);
696         if (!dev->interrupt_out_buffer) {
697                 dev_err(&intf->dev, "Couldn't allocate interrupt_out_buffer\n");
698                 goto error;
699         }
700         dev->interrupt_out_urb = usb_alloc_urb(0, GFP_KERNEL);
701         if (!dev->interrupt_out_urb) {
702                 dev_err(&intf->dev, "Couldn't allocate interrupt_out_urb\n");
703                 goto error;
704         }
705         dev->interrupt_in_interval = min_interrupt_in_interval > dev->interrupt_in_endpoint->bInterval ? min_interrupt_in_interval : dev->interrupt_in_endpoint->bInterval;
706         if (dev->interrupt_out_endpoint)
707                 dev->interrupt_out_interval = min_interrupt_out_interval > dev->interrupt_out_endpoint->bInterval ? min_interrupt_out_interval : dev->interrupt_out_endpoint->bInterval;
708
709         /* we can register the device now, as it is ready */
710         usb_set_intfdata(intf, dev);
711
712         retval = usb_register_dev(intf, &ld_usb_class);
713         if (retval) {
714                 /* something prevented us from registering this driver */
715                 dev_err(&intf->dev, "Not able to get a minor for this device.\n");
716                 usb_set_intfdata(intf, NULL);
717                 goto error;
718         }
719
720         /* let the user know what node this device is now attached to */
721         dev_info(&intf->dev, "LD USB Device #%d now attached to major %d minor %d\n",
722                 (intf->minor - USB_LD_MINOR_BASE), USB_MAJOR, intf->minor);
723
724 exit:
725         return retval;
726
727 error:
728         ld_usb_delete(dev);
729
730         return retval;
731 }
732
733 /**
734  *      ld_usb_disconnect
735  *
736  *      Called by the usb core when the device is removed from the system.
737  */
738 static void ld_usb_disconnect(struct usb_interface *intf)
739 {
740         struct ld_usb *dev;
741         int minor;
742
743         mutex_lock(&disconnect_mutex);
744
745         dev = usb_get_intfdata(intf);
746         usb_set_intfdata(intf, NULL);
747
748         down(&dev->sem);
749
750         minor = intf->minor;
751
752         /* give back our minor */
753         usb_deregister_dev(intf, &ld_usb_class);
754
755         /* if the device is not opened, then we clean up right now */
756         if (!dev->open_count) {
757                 up(&dev->sem);
758                 ld_usb_delete(dev);
759         } else {
760                 dev->intf = NULL;
761                 up(&dev->sem);
762         }
763
764         mutex_unlock(&disconnect_mutex);
765
766         dev_info(&intf->dev, "LD USB Device #%d now disconnected\n",
767                  (minor - USB_LD_MINOR_BASE));
768 }
769
770 /* usb specific object needed to register this driver with the usb subsystem */
771 static struct usb_driver ld_usb_driver = {
772         .name =         "ldusb",
773         .probe =        ld_usb_probe,
774         .disconnect =   ld_usb_disconnect,
775         .id_table =     ld_usb_table,
776 };
777
778 /**
779  *      ld_usb_init
780  */
781 static int __init ld_usb_init(void)
782 {
783         int retval;
784
785         /* register this driver with the USB subsystem */
786         retval = usb_register(&ld_usb_driver);
787         if (retval)
788                 err("usb_register failed for the "__FILE__" driver. Error number %d\n", retval);
789
790         return retval;
791 }
792
793 /**
794  *      ld_usb_exit
795  */
796 static void __exit ld_usb_exit(void)
797 {
798         /* deregister this driver with the USB subsystem */
799         usb_deregister(&ld_usb_driver);
800 }
801
802 module_init(ld_usb_init);
803 module_exit(ld_usb_exit);
804