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spi-topcliff-pch: add recovery processing in case wait-event timeout
[zen-stable.git] / drivers / usb / misc / ldusb.c
blob5db4ab52061e49d837b7042ebf7f7d9d48d44457
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
25 #include <linux/kernel.h>
26 #include <linux/errno.h>
27 #include <linux/init.h>
28 #include <linux/slab.h>
29 #include <linux/module.h>
30 #include <linux/mutex.h>
31
32 #include <asm/uaccess.h>
33 #include <linux/input.h>
34 #include <linux/usb.h>
35 #include <linux/poll.h>
36
37 /* Define these values to match your devices */
38 #define USB_VENDOR_ID_LD 0x0f11 /* USB Vendor ID of LD Didactic GmbH */
39 #define USB_DEVICE_ID_LD_CASSY 0x1000 /* USB Product ID of CASSY-S modules with 8 bytes endpoint size */
40 #define USB_DEVICE_ID_LD_CASSY2 0x1001 /* USB Product ID of CASSY-S modules with 64 bytes endpoint size */
41 #define USB_DEVICE_ID_LD_POCKETCASSY 0x1010 /* USB Product ID of Pocket-CASSY */
42 #define USB_DEVICE_ID_LD_POCKETCASSY2 0x1011 /* USB Product ID of Pocket-CASSY 2 (reserved) */
43 #define USB_DEVICE_ID_LD_MOBILECASSY 0x1020 /* USB Product ID of Mobile-CASSY */
44 #define USB_DEVICE_ID_LD_MOBILECASSY2 0x1021 /* USB Product ID of Mobile-CASSY 2 (reserved) */
45 #define USB_DEVICE_ID_LD_MICROCASSYVOLTAGE 0x1031 /* USB Product ID of Micro-CASSY Voltage */
46 #define USB_DEVICE_ID_LD_MICROCASSYCURRENT 0x1032 /* USB Product ID of Micro-CASSY Current */
47 #define USB_DEVICE_ID_LD_MICROCASSYTIME 0x1033 /* USB Product ID of Micro-CASSY Time (reserved) */
48 #define USB_DEVICE_ID_LD_MICROCASSYTEMPERATURE 0x1035 /* USB Product ID of Micro-CASSY Temperature */
49 #define USB_DEVICE_ID_LD_MICROCASSYPH 0x1038 /* USB Product ID of Micro-CASSY pH */
50 #define USB_DEVICE_ID_LD_JWM 0x1080 /* USB Product ID of Joule and Wattmeter */
51 #define USB_DEVICE_ID_LD_DMMP 0x1081 /* USB Product ID of Digital Multimeter P (reserved) */
52 #define USB_DEVICE_ID_LD_UMIP 0x1090 /* USB Product ID of UMI P */
53 #define USB_DEVICE_ID_LD_UMIC 0x10A0 /* USB Product ID of UMI C */
54 #define USB_DEVICE_ID_LD_UMIB 0x10B0 /* USB Product ID of UMI B */
55 #define USB_DEVICE_ID_LD_XRAY 0x1100 /* USB Product ID of X-Ray Apparatus 55481 */
56 #define USB_DEVICE_ID_LD_XRAY2 0x1101 /* USB Product ID of X-Ray Apparatus 554800 */
57 #define USB_DEVICE_ID_LD_XRAYCT 0x1110 /* USB Product ID of X-Ray Apparatus CT 554821*/
58 #define USB_DEVICE_ID_LD_VIDEOCOM 0x1200 /* USB Product ID of VideoCom */
59 #define USB_DEVICE_ID_LD_MOTOR 0x1210 /* USB Product ID of Motor (reserved) */
60 #define USB_DEVICE_ID_LD_COM3LAB 0x2000 /* USB Product ID of COM3LAB */
61 #define USB_DEVICE_ID_LD_TELEPORT 0x2010 /* USB Product ID of Terminal Adapter */
62 #define USB_DEVICE_ID_LD_NETWORKANALYSER 0x2020 /* USB Product ID of Network Analyser */
63 #define USB_DEVICE_ID_LD_POWERCONTROL 0x2030 /* USB Product ID of Converter Control Unit */
64 #define USB_DEVICE_ID_LD_MACHINETEST 0x2040 /* USB Product ID of Machine Test System */
65 #define USB_DEVICE_ID_LD_MOSTANALYSER 0x2050 /* USB Product ID of MOST Protocol Analyser */
66 #define USB_DEVICE_ID_LD_MOSTANALYSER2 0x2051 /* USB Product ID of MOST Protocol Analyser 2 */
67 #define USB_DEVICE_ID_LD_ABSESP 0x2060 /* USB Product ID of ABS ESP */
68 #define USB_DEVICE_ID_LD_AUTODATABUS 0x2070 /* USB Product ID of Automotive Data Buses */
69 #define USB_DEVICE_ID_LD_MCT 0x2080 /* USB Product ID of Microcontroller technique */
70 #define USB_DEVICE_ID_LD_HYBRID 0x2090 /* USB Product ID of Automotive Hybrid */
71 #define USB_DEVICE_ID_LD_HEATCONTROL 0x20A0 /* USB Product ID of Heat control */
72
73 #define USB_VENDOR_ID_VERNIER 0x08f7
74 #define USB_DEVICE_ID_VERNIER_GOTEMP 0x0002
75 #define USB_DEVICE_ID_VERNIER_SKIP 0x0003
76 #define USB_DEVICE_ID_VERNIER_CYCLOPS 0x0004
77 #define USB_DEVICE_ID_VERNIER_LCSPEC 0x0006
78
79 #ifdef CONFIG_USB_DYNAMIC_MINORS
80 #define USB_LD_MINOR_BASE 0
81 #else
82 #define USB_LD_MINOR_BASE 176
83 #endif
84
85 /* table of devices that work with this driver */
86 static const struct usb_device_id ld_usb_table[] = {
87 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_CASSY) },
88 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_CASSY2) },
89 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_POCKETCASSY) },
90 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_POCKETCASSY2) },
91 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_MOBILECASSY) },
92 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_MOBILECASSY2) },
93 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_MICROCASSYVOLTAGE) },
94 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_MICROCASSYCURRENT) },
95 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_MICROCASSYTIME) },
96 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_MICROCASSYTEMPERATURE) },
97 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_MICROCASSYPH) },
98 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_JWM) },
99 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_DMMP) },
100 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_UMIP) },
101 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_UMIC) },
102 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_UMIB) },
103 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_XRAY) },
104 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_XRAY2) },
105 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_VIDEOCOM) },
106 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_MOTOR) },
107 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_COM3LAB) },
108 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_TELEPORT) },
109 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_NETWORKANALYSER) },
110 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_POWERCONTROL) },
111 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_MACHINETEST) },
112 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_MOSTANALYSER) },
113 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_MOSTANALYSER2) },
114 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_ABSESP) },
115 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_AUTODATABUS) },
116 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_MCT) },
117 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_HYBRID) },
118 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_HEATCONTROL) },
119 { USB_DEVICE(USB_VENDOR_ID_VERNIER, USB_DEVICE_ID_VERNIER_GOTEMP) },
120 { USB_DEVICE(USB_VENDOR_ID_VERNIER, USB_DEVICE_ID_VERNIER_SKIP) },
121 { USB_DEVICE(USB_VENDOR_ID_VERNIER, USB_DEVICE_ID_VERNIER_CYCLOPS) },
122 { USB_DEVICE(USB_VENDOR_ID_VERNIER, USB_DEVICE_ID_VERNIER_LCSPEC) },
123 { } /* Terminating entry */
124 };
125 MODULE_DEVICE_TABLE(usb, ld_usb_table);
126 MODULE_VERSION("V0.14");
127 MODULE_AUTHOR("Michael Hund <mhund@ld-didactic.de>");
128 MODULE_DESCRIPTION("LD USB Driver");
129 MODULE_LICENSE("GPL");
130 MODULE_SUPPORTED_DEVICE("LD USB Devices");
131
132 #ifdef CONFIG_USB_DEBUG
133 static int debug = 1;
134 #else
135 static int debug = 0;
136 #endif
137
138 /* Use our own dbg macro */
139 #define dbg_info(dev, format, arg...) do { if (debug) dev_info(dev , format , ## arg); } while (0)
140
141 /* Module parameters */
142 module_param(debug, int, S_IRUGO | S_IWUSR);
143 MODULE_PARM_DESC(debug, "Debug enabled or not");
144
145 /* All interrupt in transfers are collected in a ring buffer to
146 * avoid racing conditions and get better performance of the driver.
147 */
148 static int ring_buffer_size = 128;
149 module_param(ring_buffer_size, int, 0);
150 MODULE_PARM_DESC(ring_buffer_size, "Read ring buffer size in reports");
151
152 /* The write_buffer can contain more than one interrupt out transfer.
153 */
154 static int write_buffer_size = 10;
155 module_param(write_buffer_size, int, 0);
156 MODULE_PARM_DESC(write_buffer_size, "Write buffer size in reports");
157
158 /* As of kernel version 2.6.4 ehci-hcd uses an
159 * "only one interrupt transfer per frame" shortcut
160 * to simplify the scheduling of periodic transfers.
161 * This conflicts with our standard 1ms intervals for in and out URBs.
162 * We use default intervals of 2ms for in and 2ms for out transfers,
163 * which should be fast enough.
164 * Increase the interval to allow more devices that do interrupt transfers,
165 * or set to 1 to use the standard interval from the endpoint descriptors.
166 */
167 static int min_interrupt_in_interval = 2;
168 module_param(min_interrupt_in_interval, int, 0);
169 MODULE_PARM_DESC(min_interrupt_in_interval, "Minimum interrupt in interval in ms");
170
171 static int min_interrupt_out_interval = 2;
172 module_param(min_interrupt_out_interval, int, 0);
173 MODULE_PARM_DESC(min_interrupt_out_interval, "Minimum interrupt out interval in ms");
174
175 /* Structure to hold all of our device specific stuff */
176 struct ld_usb {
177 struct mutex mutex; /* locks this structure */
178 struct usb_interface* intf; /* save off the usb interface pointer */
179
180 int open_count; /* number of times this port has been opened */
181
182 char* ring_buffer;
183 unsigned int ring_head;
184 unsigned int ring_tail;
185
186 wait_queue_head_t read_wait;
187 wait_queue_head_t write_wait;
188
189 char* interrupt_in_buffer;
190 struct usb_endpoint_descriptor* interrupt_in_endpoint;
191 struct urb* interrupt_in_urb;
192 int interrupt_in_interval;
193 size_t interrupt_in_endpoint_size;
194 int interrupt_in_running;
195 int interrupt_in_done;
196 int buffer_overflow;
197 spinlock_t rbsl;
198
199 char* interrupt_out_buffer;
200 struct usb_endpoint_descriptor* interrupt_out_endpoint;
201 struct urb* interrupt_out_urb;
202 int interrupt_out_interval;
203 size_t interrupt_out_endpoint_size;
204 int interrupt_out_busy;
205 };
206
207 static struct usb_driver ld_usb_driver;
208
209 /**
210 * ld_usb_abort_transfers
211 * aborts transfers and frees associated data structures
212 */
213 static void ld_usb_abort_transfers(struct ld_usb *dev)
214 {
215 /* shutdown transfer */
216 if (dev->interrupt_in_running) {
217 dev->interrupt_in_running = 0;
218 if (dev->intf)
219 usb_kill_urb(dev->interrupt_in_urb);
220 }
221 if (dev->interrupt_out_busy)
222 if (dev->intf)
223 usb_kill_urb(dev->interrupt_out_urb);
224 }
225
226 /**
227 * ld_usb_delete
228 */
229 static void ld_usb_delete(struct ld_usb *dev)
230 {
231 ld_usb_abort_transfers(dev);
232
233 /* free data structures */
234 usb_free_urb(dev->interrupt_in_urb);
235 usb_free_urb(dev->interrupt_out_urb);
236 kfree(dev->ring_buffer);
237 kfree(dev->interrupt_in_buffer);
238 kfree(dev->interrupt_out_buffer);
239 kfree(dev);
240 }
241
242 /**
243 * ld_usb_interrupt_in_callback
244 */
245 static void ld_usb_interrupt_in_callback(struct urb *urb)
246 {
247 struct ld_usb *dev = urb->context;
248 size_t *actual_buffer;
249 unsigned int next_ring_head;
250 int status = urb->status;
251 int retval;
252
253 if (status) {
254 if (status == -ENOENT ||
255 status == -ECONNRESET ||
256 status == -ESHUTDOWN) {
257 goto exit;
258 } else {
259 dbg_info(&dev->intf->dev, "%s: nonzero status received: %d\n",
260 __func__, status);
261 spin_lock(&dev->rbsl);
262 goto resubmit; /* maybe we can recover */
263 }
264 }
265
266 spin_lock(&dev->rbsl);
267 if (urb->actual_length > 0) {
268 next_ring_head = (dev->ring_head+1) % ring_buffer_size;
269 if (next_ring_head != dev->ring_tail) {
270 actual_buffer = (size_t*)(dev->ring_buffer + dev->ring_head*(sizeof(size_t)+dev->interrupt_in_endpoint_size));
271 /* actual_buffer gets urb->actual_length + interrupt_in_buffer */
272 *actual_buffer = urb->actual_length;
273 memcpy(actual_buffer+1, dev->interrupt_in_buffer, urb->actual_length);
274 dev->ring_head = next_ring_head;
275 dbg_info(&dev->intf->dev, "%s: received %d bytes\n",
276 __func__, urb->actual_length);
277 } else {
278 dev_warn(&dev->intf->dev,
279 "Ring buffer overflow, %d bytes dropped\n",
280 urb->actual_length);
281 dev->buffer_overflow = 1;
282 }
283 }
284
285 resubmit:
286 /* resubmit if we're still running */
287 if (dev->interrupt_in_running && !dev->buffer_overflow && 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 dev->buffer_overflow = 1;
293 }
294 }
295 spin_unlock(&dev->rbsl);
296 exit:
297 dev->interrupt_in_done = 1;
298 wake_up_interruptible(&dev->read_wait);
299 }
300
301 /**
302 * ld_usb_interrupt_out_callback
303 */
304 static void ld_usb_interrupt_out_callback(struct urb *urb)
305 {
306 struct ld_usb *dev = urb->context;
307 int status = urb->status;
308
309 /* sync/async unlink faults aren't errors */
310 if (status && !(status == -ENOENT ||
311 status == -ECONNRESET ||
312 status == -ESHUTDOWN))
313 dbg_info(&dev->intf->dev,
314 "%s - nonzero write interrupt status received: %d\n",
315 __func__, status);
316
317 dev->interrupt_out_busy = 0;
318 wake_up_interruptible(&dev->write_wait);
319 }
320
321 /**
322 * ld_usb_open
323 */
324 static int ld_usb_open(struct inode *inode, struct file *file)
325 {
326 struct ld_usb *dev;
327 int subminor;
328 int retval;
329 struct usb_interface *interface;
330
331 nonseekable_open(inode, file);
332 subminor = iminor(inode);
333
334 interface = usb_find_interface(&ld_usb_driver, subminor);
335
336 if (!interface) {
337 err("%s - error, can't find device for minor %d\n",
338 __func__, subminor);
339 return -ENODEV;
340 }
341
342 dev = usb_get_intfdata(interface);
343
344 if (!dev)
345 return -ENODEV;
346
347 /* lock this device */
348 if (mutex_lock_interruptible(&dev->mutex))
349 return -ERESTARTSYS;
350
351 /* allow opening only once */
352 if (dev->open_count) {
353 retval = -EBUSY;
354 goto unlock_exit;
355 }
356 dev->open_count = 1;
357
358 /* initialize in direction */
359 dev->ring_head = 0;
360 dev->ring_tail = 0;
361 dev->buffer_overflow = 0;
362 usb_fill_int_urb(dev->interrupt_in_urb,
363 interface_to_usbdev(interface),
364 usb_rcvintpipe(interface_to_usbdev(interface),
365 dev->interrupt_in_endpoint->bEndpointAddress),
366 dev->interrupt_in_buffer,
367 dev->interrupt_in_endpoint_size,
368 ld_usb_interrupt_in_callback,
369 dev,
370 dev->interrupt_in_interval);
371
372 dev->interrupt_in_running = 1;
373 dev->interrupt_in_done = 0;
374
375 retval = usb_submit_urb(dev->interrupt_in_urb, GFP_KERNEL);
376 if (retval) {
377 dev_err(&interface->dev, "Couldn't submit interrupt_in_urb %d\n", retval);
378 dev->interrupt_in_running = 0;
379 dev->open_count = 0;
380 goto unlock_exit;
381 }
382
383 /* save device in the file's private structure */
384 file->private_data = dev;
385
386 unlock_exit:
387 mutex_unlock(&dev->mutex);
388
389 return retval;
390 }
391
392 /**
393 * ld_usb_release
394 */
395 static int ld_usb_release(struct inode *inode, struct file *file)
396 {
397 struct ld_usb *dev;
398 int retval = 0;
399
400 dev = file->private_data;
401
402 if (dev == NULL) {
403 retval = -ENODEV;
404 goto exit;
405 }
406
407 if (mutex_lock_interruptible(&dev->mutex)) {
408 retval = -ERESTARTSYS;
409 goto exit;
410 }
411
412 if (dev->open_count != 1) {
413 retval = -ENODEV;
414 goto unlock_exit;
415 }
416 if (dev->intf == NULL) {
417 /* the device was unplugged before the file was released */
418 mutex_unlock(&dev->mutex);
419 /* unlock here as ld_usb_delete frees dev */
420 ld_usb_delete(dev);
421 goto exit;
422 }
423
424 /* wait until write transfer is finished */
425 if (dev->interrupt_out_busy)
426 wait_event_interruptible_timeout(dev->write_wait, !dev->interrupt_out_busy, 2 * HZ);
427 ld_usb_abort_transfers(dev);
428 dev->open_count = 0;
429
430 unlock_exit:
431 mutex_unlock(&dev->mutex);
432
433 exit:
434 return retval;
435 }
436
437 /**
438 * ld_usb_poll
439 */
440 static unsigned int ld_usb_poll(struct file *file, poll_table *wait)
441 {
442 struct ld_usb *dev;
443 unsigned int mask = 0;
444
445 dev = file->private_data;
446
447 if (!dev->intf)
448 return POLLERR | POLLHUP;
449
450 poll_wait(file, &dev->read_wait, wait);
451 poll_wait(file, &dev->write_wait, wait);
452
453 if (dev->ring_head != dev->ring_tail)
454 mask |= POLLIN | POLLRDNORM;
455 if (!dev->interrupt_out_busy)
456 mask |= POLLOUT | POLLWRNORM;
457
458 return mask;
459 }
460
461 /**
462 * ld_usb_read
463 */
464 static ssize_t ld_usb_read(struct file *file, char __user *buffer, size_t count,
465 loff_t *ppos)
466 {
467 struct ld_usb *dev;
468 size_t *actual_buffer;
469 size_t bytes_to_read;
470 int retval = 0;
471 int rv;
472
473 dev = file->private_data;
474
475 /* verify that we actually have some data to read */
476 if (count == 0)
477 goto exit;
478
479 /* lock this object */
480 if (mutex_lock_interruptible(&dev->mutex)) {
481 retval = -ERESTARTSYS;
482 goto exit;
483 }
484
485 /* verify that the device wasn't unplugged */
486 if (dev->intf == NULL) {
487 retval = -ENODEV;
488 err("No device or device unplugged %d\n", retval);
489 goto unlock_exit;
490 }
491
492 /* wait for data */
493 spin_lock_irq(&dev->rbsl);
494 if (dev->ring_head == dev->ring_tail) {
495 dev->interrupt_in_done = 0;
496 spin_unlock_irq(&dev->rbsl);
497 if (file->f_flags & O_NONBLOCK) {
498 retval = -EAGAIN;
499 goto unlock_exit;
500 }
501 retval = wait_event_interruptible(dev->read_wait, dev->interrupt_in_done);
502 if (retval < 0)
503 goto unlock_exit;
504 } else {
505 spin_unlock_irq(&dev->rbsl);
506 }
507
508 /* actual_buffer contains actual_length + interrupt_in_buffer */
509 actual_buffer = (size_t*)(dev->ring_buffer + dev->ring_tail*(sizeof(size_t)+dev->interrupt_in_endpoint_size));
510 bytes_to_read = min(count, *actual_buffer);
511 if (bytes_to_read < *actual_buffer)
512 dev_warn(&dev->intf->dev, "Read buffer overflow, %zd bytes dropped\n",
513 *actual_buffer-bytes_to_read);
514
515 /* copy one interrupt_in_buffer from ring_buffer into userspace */
516 if (copy_to_user(buffer, actual_buffer+1, bytes_to_read)) {
517 retval = -EFAULT;
518 goto unlock_exit;
519 }
520 dev->ring_tail = (dev->ring_tail+1) % ring_buffer_size;
521
522 retval = bytes_to_read;
523
524 spin_lock_irq(&dev->rbsl);
525 if (dev->buffer_overflow) {
526 dev->buffer_overflow = 0;
527 spin_unlock_irq(&dev->rbsl);
528 rv = usb_submit_urb(dev->interrupt_in_urb, GFP_KERNEL);
529 if (rv < 0)
530 dev->buffer_overflow = 1;
531 } else {
532 spin_unlock_irq(&dev->rbsl);
533 }
534
535 unlock_exit:
536 /* unlock the device */
537 mutex_unlock(&dev->mutex);
538
539 exit:
540 return retval;
541 }
542
543 /**
544 * ld_usb_write
545 */
546 static ssize_t ld_usb_write(struct file *file, const char __user *buffer,
547 size_t count, loff_t *ppos)
548 {
549 struct ld_usb *dev;
550 size_t bytes_to_write;
551 int retval = 0;
552
553 dev = file->private_data;
554
555 /* verify that we actually have some data to write */
556 if (count == 0)
557 goto exit;
558
559 /* lock this object */
560 if (mutex_lock_interruptible(&dev->mutex)) {
561 retval = -ERESTARTSYS;
562 goto exit;
563 }
564
565 /* verify that the device wasn't unplugged */
566 if (dev->intf == NULL) {
567 retval = -ENODEV;
568 err("No device or device unplugged %d\n", retval);
569 goto unlock_exit;
570 }
571
572 /* wait until previous transfer is finished */
573 if (dev->interrupt_out_busy) {
574 if (file->f_flags & O_NONBLOCK) {
575 retval = -EAGAIN;
576 goto unlock_exit;
577 }
578 retval = wait_event_interruptible(dev->write_wait, !dev->interrupt_out_busy);
579 if (retval < 0) {
580 goto unlock_exit;
581 }
582 }
583
584 /* write the data into interrupt_out_buffer from userspace */
585 bytes_to_write = min(count, write_buffer_size*dev->interrupt_out_endpoint_size);
586 if (bytes_to_write < count)
587 dev_warn(&dev->intf->dev, "Write buffer overflow, %zd bytes dropped\n",count-bytes_to_write);
588 dbg_info(&dev->intf->dev, "%s: count = %zd, bytes_to_write = %zd\n", __func__, count, bytes_to_write);
589
590 if (copy_from_user(dev->interrupt_out_buffer, buffer, bytes_to_write)) {
591 retval = -EFAULT;
592 goto unlock_exit;
593 }
594
595 if (dev->interrupt_out_endpoint == NULL) {
596 /* try HID_REQ_SET_REPORT=9 on control_endpoint instead of interrupt_out_endpoint */
597 retval = usb_control_msg(interface_to_usbdev(dev->intf),
598 usb_sndctrlpipe(interface_to_usbdev(dev->intf), 0),
599 9,
600 USB_TYPE_CLASS | USB_RECIP_INTERFACE | USB_DIR_OUT,
601 1 << 8, 0,
602 dev->interrupt_out_buffer,
603 bytes_to_write,
604 USB_CTRL_SET_TIMEOUT * HZ);
605 if (retval < 0)
606 err("Couldn't submit HID_REQ_SET_REPORT %d\n", retval);
607 goto unlock_exit;
608 }
609
610 /* send off the urb */
611 usb_fill_int_urb(dev->interrupt_out_urb,
612 interface_to_usbdev(dev->intf),
613 usb_sndintpipe(interface_to_usbdev(dev->intf),
614 dev->interrupt_out_endpoint->bEndpointAddress),
615 dev->interrupt_out_buffer,
616 bytes_to_write,
617 ld_usb_interrupt_out_callback,
618 dev,
619 dev->interrupt_out_interval);
620
621 dev->interrupt_out_busy = 1;
622 wmb();
623
624 retval = usb_submit_urb(dev->interrupt_out_urb, GFP_KERNEL);
625 if (retval) {
626 dev->interrupt_out_busy = 0;
627 err("Couldn't submit interrupt_out_urb %d\n", retval);
628 goto unlock_exit;
629 }
630 retval = bytes_to_write;
631
632 unlock_exit:
633 /* unlock the device */
634 mutex_unlock(&dev->mutex);
635
636 exit:
637 return retval;
638 }
639
640 /* file operations needed when we register this driver */
641 static const struct file_operations ld_usb_fops = {
642 .owner = THIS_MODULE,
643 .read = ld_usb_read,
644 .write = ld_usb_write,
645 .open = ld_usb_open,
646 .release = ld_usb_release,
647 .poll = ld_usb_poll,
648 .llseek = no_llseek,
649 };
650
651 /*
652 * usb class driver info in order to get a minor number from the usb core,
653 * and to have the device registered with the driver core
654 */
655 static struct usb_class_driver ld_usb_class = {
656 .name = "ldusb%d",
657 .fops = &ld_usb_fops,
658 .minor_base = USB_LD_MINOR_BASE,
659 };
660
661 /**
662 * ld_usb_probe
663 *
664 * Called by the usb core when a new device is connected that it thinks
665 * this driver might be interested in.
666 */
667 static int ld_usb_probe(struct usb_interface *intf, const struct usb_device_id *id)
668 {
669 struct usb_device *udev = interface_to_usbdev(intf);
670 struct ld_usb *dev = NULL;
671 struct usb_host_interface *iface_desc;
672 struct usb_endpoint_descriptor *endpoint;
673 char *buffer;
674 int i;
675 int retval = -ENOMEM;
676
677 /* allocate memory for our device state and initialize it */
678
679 dev = kzalloc(sizeof(*dev), GFP_KERNEL);
680 if (dev == NULL) {
681 dev_err(&intf->dev, "Out of memory\n");
682 goto exit;
683 }
684 mutex_init(&dev->mutex);
685 spin_lock_init(&dev->rbsl);
686 dev->intf = intf;
687 init_waitqueue_head(&dev->read_wait);
688 init_waitqueue_head(&dev->write_wait);
689
690 /* workaround for early firmware versions on fast computers */
691 if ((le16_to_cpu(udev->descriptor.idVendor) == USB_VENDOR_ID_LD) &&
692 ((le16_to_cpu(udev->descriptor.idProduct) == USB_DEVICE_ID_LD_CASSY) ||
693 (le16_to_cpu(udev->descriptor.idProduct) == USB_DEVICE_ID_LD_COM3LAB)) &&
694 (le16_to_cpu(udev->descriptor.bcdDevice) <= 0x103)) {
695 buffer = kmalloc(256, GFP_KERNEL);
696 if (buffer == NULL) {
697 dev_err(&intf->dev, "Couldn't allocate string buffer\n");
698 goto error;
699 }
700 /* usb_string makes SETUP+STALL to leave always ControlReadLoop */
701 usb_string(udev, 255, buffer, 256);
702 kfree(buffer);
703 }
704
705 iface_desc = intf->cur_altsetting;
706
707 /* set up the endpoint information */
708 for (i = 0; i < iface_desc->desc.bNumEndpoints; ++i) {
709 endpoint = &iface_desc->endpoint[i].desc;
710
711 if (usb_endpoint_is_int_in(endpoint))
712 dev->interrupt_in_endpoint = endpoint;
713
714 if (usb_endpoint_is_int_out(endpoint))
715 dev->interrupt_out_endpoint = endpoint;
716 }
717 if (dev->interrupt_in_endpoint == NULL) {
718 dev_err(&intf->dev, "Interrupt in endpoint not found\n");
719 goto error;
720 }
721 if (dev->interrupt_out_endpoint == NULL)
722 dev_warn(&intf->dev, "Interrupt out endpoint not found (using control endpoint instead)\n");
723
724 dev->interrupt_in_endpoint_size = usb_endpoint_maxp(dev->interrupt_in_endpoint);
725 dev->ring_buffer = kmalloc(ring_buffer_size*(sizeof(size_t)+dev->interrupt_in_endpoint_size), GFP_KERNEL);
726 if (!dev->ring_buffer) {
727 dev_err(&intf->dev, "Couldn't allocate ring_buffer\n");
728 goto error;
729 }
730 dev->interrupt_in_buffer = kmalloc(dev->interrupt_in_endpoint_size, GFP_KERNEL);
731 if (!dev->interrupt_in_buffer) {
732 dev_err(&intf->dev, "Couldn't allocate interrupt_in_buffer\n");
733 goto error;
734 }
735 dev->interrupt_in_urb = usb_alloc_urb(0, GFP_KERNEL);
736 if (!dev->interrupt_in_urb) {
737 dev_err(&intf->dev, "Couldn't allocate interrupt_in_urb\n");
738 goto error;
739 }
740 dev->interrupt_out_endpoint_size = dev->interrupt_out_endpoint ? usb_endpoint_maxp(dev->interrupt_out_endpoint) :
741 udev->descriptor.bMaxPacketSize0;
742 dev->interrupt_out_buffer = kmalloc(write_buffer_size*dev->interrupt_out_endpoint_size, GFP_KERNEL);
743 if (!dev->interrupt_out_buffer) {
744 dev_err(&intf->dev, "Couldn't allocate interrupt_out_buffer\n");
745 goto error;
746 }
747 dev->interrupt_out_urb = usb_alloc_urb(0, GFP_KERNEL);
748 if (!dev->interrupt_out_urb) {
749 dev_err(&intf->dev, "Couldn't allocate interrupt_out_urb\n");
750 goto error;
751 }
752 dev->interrupt_in_interval = min_interrupt_in_interval > dev->interrupt_in_endpoint->bInterval ? min_interrupt_in_interval : dev->interrupt_in_endpoint->bInterval;
753 if (dev->interrupt_out_endpoint)
754 dev->interrupt_out_interval = min_interrupt_out_interval > dev->interrupt_out_endpoint->bInterval ? min_interrupt_out_interval : dev->interrupt_out_endpoint->bInterval;
755
756 /* we can register the device now, as it is ready */
757 usb_set_intfdata(intf, dev);
758
759 retval = usb_register_dev(intf, &ld_usb_class);
760 if (retval) {
761 /* something prevented us from registering this driver */
762 dev_err(&intf->dev, "Not able to get a minor for this device.\n");
763 usb_set_intfdata(intf, NULL);
764 goto error;
765 }
766
767 /* let the user know what node this device is now attached to */
768 dev_info(&intf->dev, "LD USB Device #%d now attached to major %d minor %d\n",
769 (intf->minor - USB_LD_MINOR_BASE), USB_MAJOR, intf->minor);
770
771 exit:
772 return retval;
773
774 error:
775 ld_usb_delete(dev);
776
777 return retval;
778 }
779
780 /**
781 * ld_usb_disconnect
782 *
783 * Called by the usb core when the device is removed from the system.
784 */
785 static void ld_usb_disconnect(struct usb_interface *intf)
786 {
787 struct ld_usb *dev;
788 int minor;
789
790 dev = usb_get_intfdata(intf);
791 usb_set_intfdata(intf, NULL);
792
793 minor = intf->minor;
794
795 /* give back our minor */
796 usb_deregister_dev(intf, &ld_usb_class);
797
798 mutex_lock(&dev->mutex);
799
800 /* if the device is not opened, then we clean up right now */
801 if (!dev->open_count) {
802 mutex_unlock(&dev->mutex);
803 ld_usb_delete(dev);
804 } else {
805 dev->intf = NULL;
806 /* wake up pollers */
807 wake_up_interruptible_all(&dev->read_wait);
808 wake_up_interruptible_all(&dev->write_wait);
809 mutex_unlock(&dev->mutex);
810 }
811
812 dev_info(&intf->dev, "LD USB Device #%d now disconnected\n",
813 (minor - USB_LD_MINOR_BASE));
814 }
815
816 /* usb specific object needed to register this driver with the usb subsystem */
817 static struct usb_driver ld_usb_driver = {
818 .name = "ldusb",
819 .probe = ld_usb_probe,
820 .disconnect = ld_usb_disconnect,
821 .id_table = ld_usb_table,
822 };
823
824 module_usb_driver(ld_usb_driver);
825