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USB: add SPDX identifiers to all remaining files in drivers/usb/
[mirror_ubuntu-jammy-kernel.git] / drivers / usb / misc / ldusb.c
1 // SPDX-License-Identifier: GPL-2.0+
2 /**
3 * Generic USB driver for report based interrupt in/out devices
4 * like LD Didactic's USB devices. LD Didactic's USB devices are
5 * HID devices which do not use HID report definitons (they use
6 * raw interrupt in and our reports only for communication).
7 *
8 * This driver uses a ring buffer for time critical reading of
9 * interrupt in reports and provides read and write methods for
10 * raw interrupt reports (similar to the Windows HID driver).
11 * Devices based on the book USB COMPLETE by Jan Axelson may need
12 * such a compatibility to the Windows HID driver.
13 *
14 * Copyright (C) 2005 Michael Hund <mhund@ld-didactic.de>
15 *
16 * This program is free software; you can redistribute it and/or
17 * modify it under the terms of the GNU General Public License as
18 * published by the Free Software Foundation; either version 2 of
19 * the License, or (at your option) any later version.
20 *
21 * Derived from Lego USB Tower driver
22 * Copyright (C) 2003 David Glance <advidgsf@sourceforge.net>
23 * 2001-2004 Juergen Stuber <starblue@users.sourceforge.net>
24 */
25
26 #include <linux/kernel.h>
27 #include <linux/errno.h>
28 #include <linux/slab.h>
29 #include <linux/module.h>
30 #include <linux/mutex.h>
31
32 #include <linux/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 #ifdef CONFIG_USB_DYNAMIC_MINORS
74 #define USB_LD_MINOR_BASE 0
75 #else
76 #define USB_LD_MINOR_BASE 176
77 #endif
78
79 /* table of devices that work with this driver */
80 static const struct usb_device_id ld_usb_table[] = {
81 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_CASSY) },
82 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_CASSY2) },
83 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_POCKETCASSY) },
84 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_POCKETCASSY2) },
85 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_MOBILECASSY) },
86 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_MOBILECASSY2) },
87 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_MICROCASSYVOLTAGE) },
88 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_MICROCASSYCURRENT) },
89 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_MICROCASSYTIME) },
90 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_MICROCASSYTEMPERATURE) },
91 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_MICROCASSYPH) },
92 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_JWM) },
93 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_DMMP) },
94 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_UMIP) },
95 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_UMIC) },
96 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_UMIB) },
97 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_XRAY) },
98 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_XRAY2) },
99 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_VIDEOCOM) },
100 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_MOTOR) },
101 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_COM3LAB) },
102 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_TELEPORT) },
103 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_NETWORKANALYSER) },
104 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_POWERCONTROL) },
105 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_MACHINETEST) },
106 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_MOSTANALYSER) },
107 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_MOSTANALYSER2) },
108 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_ABSESP) },
109 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_AUTODATABUS) },
110 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_MCT) },
111 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_HYBRID) },
112 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_HEATCONTROL) },
113 { } /* Terminating entry */
114 };
115 MODULE_DEVICE_TABLE(usb, ld_usb_table);
116 MODULE_AUTHOR("Michael Hund <mhund@ld-didactic.de>");
117 MODULE_DESCRIPTION("LD USB Driver");
118 MODULE_LICENSE("GPL");
119 MODULE_SUPPORTED_DEVICE("LD USB Devices");
120
121 /* All interrupt in transfers are collected in a ring buffer to
122 * avoid racing conditions and get better performance of the driver.
123 */
124 static int ring_buffer_size = 128;
125 module_param(ring_buffer_size, int, 0000);
126 MODULE_PARM_DESC(ring_buffer_size, "Read ring buffer size in reports");
127
128 /* The write_buffer can contain more than one interrupt out transfer.
129 */
130 static int write_buffer_size = 10;
131 module_param(write_buffer_size, int, 0000);
132 MODULE_PARM_DESC(write_buffer_size, "Write buffer size in reports");
133
134 /* As of kernel version 2.6.4 ehci-hcd uses an
135 * "only one interrupt transfer per frame" shortcut
136 * to simplify the scheduling of periodic transfers.
137 * This conflicts with our standard 1ms intervals for in and out URBs.
138 * We use default intervals of 2ms for in and 2ms for out transfers,
139 * which should be fast enough.
140 * Increase the interval to allow more devices that do interrupt transfers,
141 * or set to 1 to use the standard interval from the endpoint descriptors.
142 */
143 static int min_interrupt_in_interval = 2;
144 module_param(min_interrupt_in_interval, int, 0000);
145 MODULE_PARM_DESC(min_interrupt_in_interval, "Minimum interrupt in interval in ms");
146
147 static int min_interrupt_out_interval = 2;
148 module_param(min_interrupt_out_interval, int, 0000);
149 MODULE_PARM_DESC(min_interrupt_out_interval, "Minimum interrupt out interval in ms");
150
151 /* Structure to hold all of our device specific stuff */
152 struct ld_usb {
153 struct mutex mutex; /* locks this structure */
154 struct usb_interface *intf; /* save off the usb interface pointer */
155
156 int open_count; /* number of times this port has been opened */
157
158 char *ring_buffer;
159 unsigned int ring_head;
160 unsigned int ring_tail;
161
162 wait_queue_head_t read_wait;
163 wait_queue_head_t write_wait;
164
165 char *interrupt_in_buffer;
166 struct usb_endpoint_descriptor *interrupt_in_endpoint;
167 struct urb *interrupt_in_urb;
168 int interrupt_in_interval;
169 size_t interrupt_in_endpoint_size;
170 int interrupt_in_running;
171 int interrupt_in_done;
172 int buffer_overflow;
173 spinlock_t rbsl;
174
175 char *interrupt_out_buffer;
176 struct usb_endpoint_descriptor *interrupt_out_endpoint;
177 struct urb *interrupt_out_urb;
178 int interrupt_out_interval;
179 size_t interrupt_out_endpoint_size;
180 int interrupt_out_busy;
181 };
182
183 static struct usb_driver ld_usb_driver;
184
185 /**
186 * ld_usb_abort_transfers
187 * aborts transfers and frees associated data structures
188 */
189 static void ld_usb_abort_transfers(struct ld_usb *dev)
190 {
191 /* shutdown transfer */
192 if (dev->interrupt_in_running) {
193 dev->interrupt_in_running = 0;
194 if (dev->intf)
195 usb_kill_urb(dev->interrupt_in_urb);
196 }
197 if (dev->interrupt_out_busy)
198 if (dev->intf)
199 usb_kill_urb(dev->interrupt_out_urb);
200 }
201
202 /**
203 * ld_usb_delete
204 */
205 static void ld_usb_delete(struct ld_usb *dev)
206 {
207 ld_usb_abort_transfers(dev);
208
209 /* free data structures */
210 usb_free_urb(dev->interrupt_in_urb);
211 usb_free_urb(dev->interrupt_out_urb);
212 kfree(dev->ring_buffer);
213 kfree(dev->interrupt_in_buffer);
214 kfree(dev->interrupt_out_buffer);
215 kfree(dev);
216 }
217
218 /**
219 * ld_usb_interrupt_in_callback
220 */
221 static void ld_usb_interrupt_in_callback(struct urb *urb)
222 {
223 struct ld_usb *dev = urb->context;
224 size_t *actual_buffer;
225 unsigned int next_ring_head;
226 int status = urb->status;
227 int retval;
228
229 if (status) {
230 if (status == -ENOENT ||
231 status == -ECONNRESET ||
232 status == -ESHUTDOWN) {
233 goto exit;
234 } else {
235 dev_dbg(&dev->intf->dev,
236 "%s: nonzero status received: %d\n", __func__,
237 status);
238 spin_lock(&dev->rbsl);
239 goto resubmit; /* maybe we can recover */
240 }
241 }
242
243 spin_lock(&dev->rbsl);
244 if (urb->actual_length > 0) {
245 next_ring_head = (dev->ring_head+1) % ring_buffer_size;
246 if (next_ring_head != dev->ring_tail) {
247 actual_buffer = (size_t *)(dev->ring_buffer + dev->ring_head * (sizeof(size_t)+dev->interrupt_in_endpoint_size));
248 /* actual_buffer gets urb->actual_length + interrupt_in_buffer */
249 *actual_buffer = urb->actual_length;
250 memcpy(actual_buffer+1, dev->interrupt_in_buffer, urb->actual_length);
251 dev->ring_head = next_ring_head;
252 dev_dbg(&dev->intf->dev, "%s: received %d bytes\n",
253 __func__, urb->actual_length);
254 } else {
255 dev_warn(&dev->intf->dev,
256 "Ring buffer overflow, %d bytes dropped\n",
257 urb->actual_length);
258 dev->buffer_overflow = 1;
259 }
260 }
261
262 resubmit:
263 /* resubmit if we're still running */
264 if (dev->interrupt_in_running && !dev->buffer_overflow && dev->intf) {
265 retval = usb_submit_urb(dev->interrupt_in_urb, GFP_ATOMIC);
266 if (retval) {
267 dev_err(&dev->intf->dev,
268 "usb_submit_urb failed (%d)\n", retval);
269 dev->buffer_overflow = 1;
270 }
271 }
272 spin_unlock(&dev->rbsl);
273 exit:
274 dev->interrupt_in_done = 1;
275 wake_up_interruptible(&dev->read_wait);
276 }
277
278 /**
279 * ld_usb_interrupt_out_callback
280 */
281 static void ld_usb_interrupt_out_callback(struct urb *urb)
282 {
283 struct ld_usb *dev = urb->context;
284 int status = urb->status;
285
286 /* sync/async unlink faults aren't errors */
287 if (status && !(status == -ENOENT ||
288 status == -ECONNRESET ||
289 status == -ESHUTDOWN))
290 dev_dbg(&dev->intf->dev,
291 "%s - nonzero write interrupt status received: %d\n",
292 __func__, status);
293
294 dev->interrupt_out_busy = 0;
295 wake_up_interruptible(&dev->write_wait);
296 }
297
298 /**
299 * ld_usb_open
300 */
301 static int ld_usb_open(struct inode *inode, struct file *file)
302 {
303 struct ld_usb *dev;
304 int subminor;
305 int retval;
306 struct usb_interface *interface;
307
308 nonseekable_open(inode, file);
309 subminor = iminor(inode);
310
311 interface = usb_find_interface(&ld_usb_driver, subminor);
312
313 if (!interface) {
314 printk(KERN_ERR "%s - error, can't find device for minor %d\n",
315 __func__, subminor);
316 return -ENODEV;
317 }
318
319 dev = usb_get_intfdata(interface);
320
321 if (!dev)
322 return -ENODEV;
323
324 /* lock this device */
325 if (mutex_lock_interruptible(&dev->mutex))
326 return -ERESTARTSYS;
327
328 /* allow opening only once */
329 if (dev->open_count) {
330 retval = -EBUSY;
331 goto unlock_exit;
332 }
333 dev->open_count = 1;
334
335 /* initialize in direction */
336 dev->ring_head = 0;
337 dev->ring_tail = 0;
338 dev->buffer_overflow = 0;
339 usb_fill_int_urb(dev->interrupt_in_urb,
340 interface_to_usbdev(interface),
341 usb_rcvintpipe(interface_to_usbdev(interface),
342 dev->interrupt_in_endpoint->bEndpointAddress),
343 dev->interrupt_in_buffer,
344 dev->interrupt_in_endpoint_size,
345 ld_usb_interrupt_in_callback,
346 dev,
347 dev->interrupt_in_interval);
348
349 dev->interrupt_in_running = 1;
350 dev->interrupt_in_done = 0;
351
352 retval = usb_submit_urb(dev->interrupt_in_urb, GFP_KERNEL);
353 if (retval) {
354 dev_err(&interface->dev, "Couldn't submit interrupt_in_urb %d\n", retval);
355 dev->interrupt_in_running = 0;
356 dev->open_count = 0;
357 goto unlock_exit;
358 }
359
360 /* save device in the file's private structure */
361 file->private_data = dev;
362
363 unlock_exit:
364 mutex_unlock(&dev->mutex);
365
366 return retval;
367 }
368
369 /**
370 * ld_usb_release
371 */
372 static int ld_usb_release(struct inode *inode, struct file *file)
373 {
374 struct ld_usb *dev;
375 int retval = 0;
376
377 dev = file->private_data;
378
379 if (dev == NULL) {
380 retval = -ENODEV;
381 goto exit;
382 }
383
384 if (mutex_lock_interruptible(&dev->mutex)) {
385 retval = -ERESTARTSYS;
386 goto exit;
387 }
388
389 if (dev->open_count != 1) {
390 retval = -ENODEV;
391 goto unlock_exit;
392 }
393 if (dev->intf == NULL) {
394 /* the device was unplugged before the file was released */
395 mutex_unlock(&dev->mutex);
396 /* unlock here as ld_usb_delete frees dev */
397 ld_usb_delete(dev);
398 goto exit;
399 }
400
401 /* wait until write transfer is finished */
402 if (dev->interrupt_out_busy)
403 wait_event_interruptible_timeout(dev->write_wait, !dev->interrupt_out_busy, 2 * HZ);
404 ld_usb_abort_transfers(dev);
405 dev->open_count = 0;
406
407 unlock_exit:
408 mutex_unlock(&dev->mutex);
409
410 exit:
411 return retval;
412 }
413
414 /**
415 * ld_usb_poll
416 */
417 static unsigned int ld_usb_poll(struct file *file, poll_table *wait)
418 {
419 struct ld_usb *dev;
420 unsigned int mask = 0;
421
422 dev = file->private_data;
423
424 if (!dev->intf)
425 return POLLERR | POLLHUP;
426
427 poll_wait(file, &dev->read_wait, wait);
428 poll_wait(file, &dev->write_wait, wait);
429
430 if (dev->ring_head != dev->ring_tail)
431 mask |= POLLIN | POLLRDNORM;
432 if (!dev->interrupt_out_busy)
433 mask |= POLLOUT | POLLWRNORM;
434
435 return mask;
436 }
437
438 /**
439 * ld_usb_read
440 */
441 static ssize_t ld_usb_read(struct file *file, char __user *buffer, size_t count,
442 loff_t *ppos)
443 {
444 struct ld_usb *dev;
445 size_t *actual_buffer;
446 size_t bytes_to_read;
447 int retval = 0;
448 int rv;
449
450 dev = file->private_data;
451
452 /* verify that we actually have some data to read */
453 if (count == 0)
454 goto exit;
455
456 /* lock this object */
457 if (mutex_lock_interruptible(&dev->mutex)) {
458 retval = -ERESTARTSYS;
459 goto exit;
460 }
461
462 /* verify that the device wasn't unplugged */
463 if (dev->intf == NULL) {
464 retval = -ENODEV;
465 printk(KERN_ERR "ldusb: No device or device unplugged %d\n", retval);
466 goto unlock_exit;
467 }
468
469 /* wait for data */
470 spin_lock_irq(&dev->rbsl);
471 if (dev->ring_head == dev->ring_tail) {
472 dev->interrupt_in_done = 0;
473 spin_unlock_irq(&dev->rbsl);
474 if (file->f_flags & O_NONBLOCK) {
475 retval = -EAGAIN;
476 goto unlock_exit;
477 }
478 retval = wait_event_interruptible(dev->read_wait, dev->interrupt_in_done);
479 if (retval < 0)
480 goto unlock_exit;
481 } else {
482 spin_unlock_irq(&dev->rbsl);
483 }
484
485 /* actual_buffer contains actual_length + interrupt_in_buffer */
486 actual_buffer = (size_t *)(dev->ring_buffer + dev->ring_tail * (sizeof(size_t)+dev->interrupt_in_endpoint_size));
487 bytes_to_read = min(count, *actual_buffer);
488 if (bytes_to_read < *actual_buffer)
489 dev_warn(&dev->intf->dev, "Read buffer overflow, %zd bytes dropped\n",
490 *actual_buffer-bytes_to_read);
491
492 /* copy one interrupt_in_buffer from ring_buffer into userspace */
493 if (copy_to_user(buffer, actual_buffer+1, bytes_to_read)) {
494 retval = -EFAULT;
495 goto unlock_exit;
496 }
497 dev->ring_tail = (dev->ring_tail+1) % ring_buffer_size;
498
499 retval = bytes_to_read;
500
501 spin_lock_irq(&dev->rbsl);
502 if (dev->buffer_overflow) {
503 dev->buffer_overflow = 0;
504 spin_unlock_irq(&dev->rbsl);
505 rv = usb_submit_urb(dev->interrupt_in_urb, GFP_KERNEL);
506 if (rv < 0)
507 dev->buffer_overflow = 1;
508 } else {
509 spin_unlock_irq(&dev->rbsl);
510 }
511
512 unlock_exit:
513 /* unlock the device */
514 mutex_unlock(&dev->mutex);
515
516 exit:
517 return retval;
518 }
519
520 /**
521 * ld_usb_write
522 */
523 static ssize_t ld_usb_write(struct file *file, const char __user *buffer,
524 size_t count, loff_t *ppos)
525 {
526 struct ld_usb *dev;
527 size_t bytes_to_write;
528 int retval = 0;
529
530 dev = file->private_data;
531
532 /* verify that we actually have some data to write */
533 if (count == 0)
534 goto exit;
535
536 /* lock this object */
537 if (mutex_lock_interruptible(&dev->mutex)) {
538 retval = -ERESTARTSYS;
539 goto exit;
540 }
541
542 /* verify that the device wasn't unplugged */
543 if (dev->intf == NULL) {
544 retval = -ENODEV;
545 printk(KERN_ERR "ldusb: No device or device unplugged %d\n", retval);
546 goto unlock_exit;
547 }
548
549 /* wait until previous transfer is finished */
550 if (dev->interrupt_out_busy) {
551 if (file->f_flags & O_NONBLOCK) {
552 retval = -EAGAIN;
553 goto unlock_exit;
554 }
555 retval = wait_event_interruptible(dev->write_wait, !dev->interrupt_out_busy);
556 if (retval < 0) {
557 goto unlock_exit;
558 }
559 }
560
561 /* write the data into interrupt_out_buffer from userspace */
562 bytes_to_write = min(count, write_buffer_size*dev->interrupt_out_endpoint_size);
563 if (bytes_to_write < count)
564 dev_warn(&dev->intf->dev, "Write buffer overflow, %zd bytes dropped\n", count-bytes_to_write);
565 dev_dbg(&dev->intf->dev, "%s: count = %zd, bytes_to_write = %zd\n",
566 __func__, count, bytes_to_write);
567
568 if (copy_from_user(dev->interrupt_out_buffer, buffer, bytes_to_write)) {
569 retval = -EFAULT;
570 goto unlock_exit;
571 }
572
573 if (dev->interrupt_out_endpoint == NULL) {
574 /* try HID_REQ_SET_REPORT=9 on control_endpoint instead of interrupt_out_endpoint */
575 retval = usb_control_msg(interface_to_usbdev(dev->intf),
576 usb_sndctrlpipe(interface_to_usbdev(dev->intf), 0),
577 9,
578 USB_TYPE_CLASS | USB_RECIP_INTERFACE | USB_DIR_OUT,
579 1 << 8, 0,
580 dev->interrupt_out_buffer,
581 bytes_to_write,
582 USB_CTRL_SET_TIMEOUT * HZ);
583 if (retval < 0)
584 dev_err(&dev->intf->dev,
585 "Couldn't submit HID_REQ_SET_REPORT %d\n",
586 retval);
587 goto unlock_exit;
588 }
589
590 /* send off the urb */
591 usb_fill_int_urb(dev->interrupt_out_urb,
592 interface_to_usbdev(dev->intf),
593 usb_sndintpipe(interface_to_usbdev(dev->intf),
594 dev->interrupt_out_endpoint->bEndpointAddress),
595 dev->interrupt_out_buffer,
596 bytes_to_write,
597 ld_usb_interrupt_out_callback,
598 dev,
599 dev->interrupt_out_interval);
600
601 dev->interrupt_out_busy = 1;
602 wmb();
603
604 retval = usb_submit_urb(dev->interrupt_out_urb, GFP_KERNEL);
605 if (retval) {
606 dev->interrupt_out_busy = 0;
607 dev_err(&dev->intf->dev,
608 "Couldn't submit interrupt_out_urb %d\n", retval);
609 goto unlock_exit;
610 }
611 retval = bytes_to_write;
612
613 unlock_exit:
614 /* unlock the device */
615 mutex_unlock(&dev->mutex);
616
617 exit:
618 return retval;
619 }
620
621 /* file operations needed when we register this driver */
622 static const struct file_operations ld_usb_fops = {
623 .owner = THIS_MODULE,
624 .read = ld_usb_read,
625 .write = ld_usb_write,
626 .open = ld_usb_open,
627 .release = ld_usb_release,
628 .poll = ld_usb_poll,
629 .llseek = no_llseek,
630 };
631
632 /*
633 * usb class driver info in order to get a minor number from the usb core,
634 * and to have the device registered with the driver core
635 */
636 static struct usb_class_driver ld_usb_class = {
637 .name = "ldusb%d",
638 .fops = &ld_usb_fops,
639 .minor_base = USB_LD_MINOR_BASE,
640 };
641
642 /**
643 * ld_usb_probe
644 *
645 * Called by the usb core when a new device is connected that it thinks
646 * this driver might be interested in.
647 */
648 static int ld_usb_probe(struct usb_interface *intf, const struct usb_device_id *id)
649 {
650 struct usb_device *udev = interface_to_usbdev(intf);
651 struct ld_usb *dev = NULL;
652 struct usb_host_interface *iface_desc;
653 char *buffer;
654 int retval = -ENOMEM;
655 int res;
656
657 /* allocate memory for our device state and initialize it */
658
659 dev = kzalloc(sizeof(*dev), GFP_KERNEL);
660 if (!dev)
661 goto exit;
662 mutex_init(&dev->mutex);
663 spin_lock_init(&dev->rbsl);
664 dev->intf = intf;
665 init_waitqueue_head(&dev->read_wait);
666 init_waitqueue_head(&dev->write_wait);
667
668 /* workaround for early firmware versions on fast computers */
669 if ((le16_to_cpu(udev->descriptor.idVendor) == USB_VENDOR_ID_LD) &&
670 ((le16_to_cpu(udev->descriptor.idProduct) == USB_DEVICE_ID_LD_CASSY) ||
671 (le16_to_cpu(udev->descriptor.idProduct) == USB_DEVICE_ID_LD_COM3LAB)) &&
672 (le16_to_cpu(udev->descriptor.bcdDevice) <= 0x103)) {
673 buffer = kmalloc(256, GFP_KERNEL);
674 if (!buffer)
675 goto error;
676 /* usb_string makes SETUP+STALL to leave always ControlReadLoop */
677 usb_string(udev, 255, buffer, 256);
678 kfree(buffer);
679 }
680
681 iface_desc = intf->cur_altsetting;
682
683 res = usb_find_last_int_in_endpoint(iface_desc,
684 &dev->interrupt_in_endpoint);
685 if (res) {
686 dev_err(&intf->dev, "Interrupt in endpoint not found\n");
687 retval = res;
688 goto error;
689 }
690
691 res = usb_find_last_int_out_endpoint(iface_desc,
692 &dev->interrupt_out_endpoint);
693 if (res)
694 dev_warn(&intf->dev, "Interrupt out endpoint not found (using control endpoint instead)\n");
695
696 dev->interrupt_in_endpoint_size = usb_endpoint_maxp(dev->interrupt_in_endpoint);
697 dev->ring_buffer = kmalloc(ring_buffer_size*(sizeof(size_t)+dev->interrupt_in_endpoint_size), GFP_KERNEL);
698 if (!dev->ring_buffer)
699 goto error;
700 dev->interrupt_in_buffer = kmalloc(dev->interrupt_in_endpoint_size, GFP_KERNEL);
701 if (!dev->interrupt_in_buffer)
702 goto error;
703 dev->interrupt_in_urb = usb_alloc_urb(0, GFP_KERNEL);
704 if (!dev->interrupt_in_urb)
705 goto error;
706 dev->interrupt_out_endpoint_size = dev->interrupt_out_endpoint ? usb_endpoint_maxp(dev->interrupt_out_endpoint) :
707 udev->descriptor.bMaxPacketSize0;
708 dev->interrupt_out_buffer = kmalloc(write_buffer_size*dev->interrupt_out_endpoint_size, GFP_KERNEL);
709 if (!dev->interrupt_out_buffer)
710 goto error;
711 dev->interrupt_out_urb = usb_alloc_urb(0, GFP_KERNEL);
712 if (!dev->interrupt_out_urb)
713 goto error;
714 dev->interrupt_in_interval = min_interrupt_in_interval > dev->interrupt_in_endpoint->bInterval ? min_interrupt_in_interval : dev->interrupt_in_endpoint->bInterval;
715 if (dev->interrupt_out_endpoint)
716 dev->interrupt_out_interval = min_interrupt_out_interval > dev->interrupt_out_endpoint->bInterval ? min_interrupt_out_interval : dev->interrupt_out_endpoint->bInterval;
717
718 /* we can register the device now, as it is ready */
719 usb_set_intfdata(intf, dev);
720
721 retval = usb_register_dev(intf, &ld_usb_class);
722 if (retval) {
723 /* something prevented us from registering this driver */
724 dev_err(&intf->dev, "Not able to get a minor for this device.\n");
725 usb_set_intfdata(intf, NULL);
726 goto error;
727 }
728
729 /* let the user know what node this device is now attached to */
730 dev_info(&intf->dev, "LD USB Device #%d now attached to major %d minor %d\n",
731 (intf->minor - USB_LD_MINOR_BASE), USB_MAJOR, intf->minor);
732
733 exit:
734 return retval;
735
736 error:
737 ld_usb_delete(dev);
738
739 return retval;
740 }
741
742 /**
743 * ld_usb_disconnect
744 *
745 * Called by the usb core when the device is removed from the system.
746 */
747 static void ld_usb_disconnect(struct usb_interface *intf)
748 {
749 struct ld_usb *dev;
750 int minor;
751
752 dev = usb_get_intfdata(intf);
753 usb_set_intfdata(intf, NULL);
754
755 minor = intf->minor;
756
757 /* give back our minor */
758 usb_deregister_dev(intf, &ld_usb_class);
759
760 mutex_lock(&dev->mutex);
761
762 /* if the device is not opened, then we clean up right now */
763 if (!dev->open_count) {
764 mutex_unlock(&dev->mutex);
765 ld_usb_delete(dev);
766 } else {
767 dev->intf = NULL;
768 /* wake up pollers */
769 wake_up_interruptible_all(&dev->read_wait);
770 wake_up_interruptible_all(&dev->write_wait);
771 mutex_unlock(&dev->mutex);
772 }
773
774 dev_info(&intf->dev, "LD USB Device #%d now disconnected\n",
775 (minor - USB_LD_MINOR_BASE));
776 }
777
778 /* usb specific object needed to register this driver with the usb subsystem */
779 static struct usb_driver ld_usb_driver = {
780 .name = "ldusb",
781 .probe = ld_usb_probe,
782 .disconnect = ld_usb_disconnect,
783 .id_table = ld_usb_table,
784 };
785
786 module_usb_driver(ld_usb_driver);
787
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