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Merge branch 'upstream' of git://git.infradead.org/users/pcmoore/audit
[linux-2.6-block.git] / drivers / usb / misc / ldusb.c
CommitLineData
2824bd25
MH		 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>
2824bd25
MH		 23 */
24
2824bd25
MH		 25#include <linux/kernel.h>
26#include <linux/errno.h>
2824bd25
MH		 27#include <linux/slab.h>
28#include <linux/module.h>
4186ecf8 29#include <linux/mutex.h>
2824bd25
MH		 30
31#include <asm/uaccess.h>
32#include <linux/input.h>
33#include <linux/usb.h>
34#include <linux/poll.h>
35
36/* Define these values to match your devices */
37#define USB_VENDOR_ID_LD 0x0f11 /* USB Vendor ID of LD Didactic GmbH */
ce97cac8
MH		 38#define USB_DEVICE_ID_LD_CASSY 0x1000 /* USB Product ID of CASSY-S modules with 8 bytes endpoint size */
39#define USB_DEVICE_ID_LD_CASSY2 0x1001 /* USB Product ID of CASSY-S modules with 64 bytes endpoint size */
ba3e66e9 40#define USB_DEVICE_ID_LD_POCKETCASSY 0x1010 /* USB Product ID of Pocket-CASSY */
ce97cac8 41#define USB_DEVICE_ID_LD_POCKETCASSY2 0x1011 /* USB Product ID of Pocket-CASSY 2 (reserved) */
ba3e66e9 42#define USB_DEVICE_ID_LD_MOBILECASSY 0x1020 /* USB Product ID of Mobile-CASSY */
ce97cac8
MH		 43#define USB_DEVICE_ID_LD_MOBILECASSY2 0x1021 /* USB Product ID of Mobile-CASSY 2 (reserved) */
44#define USB_DEVICE_ID_LD_MICROCASSYVOLTAGE 0x1031 /* USB Product ID of Micro-CASSY Voltage */
45#define USB_DEVICE_ID_LD_MICROCASSYCURRENT 0x1032 /* USB Product ID of Micro-CASSY Current */
46#define USB_DEVICE_ID_LD_MICROCASSYTIME 0x1033 /* USB Product ID of Micro-CASSY Time (reserved) */
47#define USB_DEVICE_ID_LD_MICROCASSYTEMPERATURE 0x1035 /* USB Product ID of Micro-CASSY Temperature */
48#define USB_DEVICE_ID_LD_MICROCASSYPH 0x1038 /* USB Product ID of Micro-CASSY pH */
ba3e66e9
MH		 49#define USB_DEVICE_ID_LD_JWM 0x1080 /* USB Product ID of Joule and Wattmeter */
50#define USB_DEVICE_ID_LD_DMMP 0x1081 /* USB Product ID of Digital Multimeter P (reserved) */
51#define USB_DEVICE_ID_LD_UMIP 0x1090 /* USB Product ID of UMI P */
ce97cac8
MH		 52#define USB_DEVICE_ID_LD_UMIC 0x10A0 /* USB Product ID of UMI C */
53#define USB_DEVICE_ID_LD_UMIB 0x10B0 /* USB Product ID of UMI B */
54#define USB_DEVICE_ID_LD_XRAY 0x1100 /* USB Product ID of X-Ray Apparatus 55481 */
55#define USB_DEVICE_ID_LD_XRAY2 0x1101 /* USB Product ID of X-Ray Apparatus 554800 */
56#define USB_DEVICE_ID_LD_XRAYCT 0x1110 /* USB Product ID of X-Ray Apparatus CT 554821*/
ba3e66e9 57#define USB_DEVICE_ID_LD_VIDEOCOM 0x1200 /* USB Product ID of VideoCom */
ce97cac8 58#define USB_DEVICE_ID_LD_MOTOR 0x1210 /* USB Product ID of Motor (reserved) */
ba3e66e9
MH		 59#define USB_DEVICE_ID_LD_COM3LAB 0x2000 /* USB Product ID of COM3LAB */
60#define USB_DEVICE_ID_LD_TELEPORT 0x2010 /* USB Product ID of Terminal Adapter */
61#define USB_DEVICE_ID_LD_NETWORKANALYSER 0x2020 /* USB Product ID of Network Analyser */
62#define USB_DEVICE_ID_LD_POWERCONTROL 0x2030 /* USB Product ID of Converter Control Unit */
63#define USB_DEVICE_ID_LD_MACHINETEST 0x2040 /* USB Product ID of Machine Test System */
ce97cac8
MH		 64#define USB_DEVICE_ID_LD_MOSTANALYSER 0x2050 /* USB Product ID of MOST Protocol Analyser */
65#define USB_DEVICE_ID_LD_MOSTANALYSER2 0x2051 /* USB Product ID of MOST Protocol Analyser 2 */
66#define USB_DEVICE_ID_LD_ABSESP 0x2060 /* USB Product ID of ABS ESP */
67#define USB_DEVICE_ID_LD_AUTODATABUS 0x2070 /* USB Product ID of Automotive Data Buses */
68#define USB_DEVICE_ID_LD_MCT 0x2080 /* USB Product ID of Microcontroller technique */
69#define USB_DEVICE_ID_LD_HYBRID 0x2090 /* USB Product ID of Automotive Hybrid */
70#define USB_DEVICE_ID_LD_HEATCONTROL 0x20A0 /* USB Product ID of Heat control */
2824bd25
MH		 71
72#define USB_VENDOR_ID_VERNIER 0x08f7
2824bd25
MH		 73#define USB_DEVICE_ID_VERNIER_GOTEMP 0x0002
74#define USB_DEVICE_ID_VERNIER_SKIP 0x0003
75#define USB_DEVICE_ID_VERNIER_CYCLOPS 0x0004
5b0a4d66 76#define USB_DEVICE_ID_VERNIER_LCSPEC 0x0006
2824bd25 77
2824bd25
MH		 78#ifdef CONFIG_USB_DYNAMIC_MINORS
79#define USB_LD_MINOR_BASE 0
80#else
81#define USB_LD_MINOR_BASE 176
82#endif
83
84/* table of devices that work with this driver */
33b9e162 85static const struct usb_device_id ld_usb_table[] = {
ba3e66e9 86 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_CASSY) },
ce97cac8 87 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_CASSY2) },
ba3e66e9 88 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_POCKETCASSY) },
ce97cac8 89 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_POCKETCASSY2) },
ba3e66e9 90 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_MOBILECASSY) },
ce97cac8
MH		 91 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_MOBILECASSY2) },
92 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_MICROCASSYVOLTAGE) },
93 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_MICROCASSYCURRENT) },
94 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_MICROCASSYTIME) },
95 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_MICROCASSYTEMPERATURE) },
96 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_MICROCASSYPH) },
ba3e66e9
MH		 97 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_JWM) },
98 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_DMMP) },
99 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_UMIP) },
ce97cac8
MH		 100 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_UMIC) },
101 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_UMIB) },
102 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_XRAY) },
ba3e66e9
MH		 103 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_XRAY2) },
104 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_VIDEOCOM) },
ce97cac8 105 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_MOTOR) },
ba3e66e9
MH		 106 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_COM3LAB) },
107 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_TELEPORT) },
108 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_NETWORKANALYSER) },
109 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_POWERCONTROL) },
110 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_MACHINETEST) },
ce97cac8
MH		 111 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_MOSTANALYSER) },
112 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_MOSTANALYSER2) },
113 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_ABSESP) },
114 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_AUTODATABUS) },
115 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_MCT) },
116 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_HYBRID) },
117 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_HEATCONTROL) },
2824bd25
MH		 118 { USB_DEVICE(USB_VENDOR_ID_VERNIER, USB_DEVICE_ID_VERNIER_GOTEMP) },
119 { USB_DEVICE(USB_VENDOR_ID_VERNIER, USB_DEVICE_ID_VERNIER_SKIP) },
120 { USB_DEVICE(USB_VENDOR_ID_VERNIER, USB_DEVICE_ID_VERNIER_CYCLOPS) },
5b0a4d66 121 { USB_DEVICE(USB_VENDOR_ID_VERNIER, USB_DEVICE_ID_VERNIER_LCSPEC) },
2824bd25
MH		 122 { } /* Terminating entry */
123};
124MODULE_DEVICE_TABLE(usb, ld_usb_table);
ce97cac8 125MODULE_VERSION("V0.14");
2824bd25
MH		 126MODULE_AUTHOR("Michael Hund <mhund@ld-didactic.de>");
127MODULE_DESCRIPTION("LD USB Driver");
128MODULE_LICENSE("GPL");
129MODULE_SUPPORTED_DEVICE("LD USB Devices");
130
2824bd25
MH		 131/* All interrupt in transfers are collected in a ring buffer to
132 * avoid racing conditions and get better performance of the driver.
133 */
134static int ring_buffer_size = 128;
135module_param(ring_buffer_size, int, 0);
136MODULE_PARM_DESC(ring_buffer_size, "Read ring buffer size in reports");
137
138/* The write_buffer can contain more than one interrupt out transfer.
139 */
140static int write_buffer_size = 10;
141module_param(write_buffer_size, int, 0);
142MODULE_PARM_DESC(write_buffer_size, "Write buffer size in reports");
143
144/* As of kernel version 2.6.4 ehci-hcd uses an
145 * "only one interrupt transfer per frame" shortcut
146 * to simplify the scheduling of periodic transfers.
147 * This conflicts with our standard 1ms intervals for in and out URBs.
148 * We use default intervals of 2ms for in and 2ms for out transfers,
149 * which should be fast enough.
150 * Increase the interval to allow more devices that do interrupt transfers,
151 * or set to 1 to use the standard interval from the endpoint descriptors.
152 */
153static int min_interrupt_in_interval = 2;
154module_param(min_interrupt_in_interval, int, 0);
155MODULE_PARM_DESC(min_interrupt_in_interval, "Minimum interrupt in interval in ms");
156
157static int min_interrupt_out_interval = 2;
158module_param(min_interrupt_out_interval, int, 0);
159MODULE_PARM_DESC(min_interrupt_out_interval, "Minimum interrupt out interval in ms");
160
161/* Structure to hold all of our device specific stuff */
162struct ld_usb {
ce0d7d3f 163 struct mutex mutex; /* locks this structure */
2824bd25
MH		 164 struct usb_interface* intf; /* save off the usb interface pointer */
165
166 int open_count; /* number of times this port has been opened */
167
168 char* ring_buffer;
169 unsigned int ring_head;
170 unsigned int ring_tail;
171
172 wait_queue_head_t read_wait;
173 wait_queue_head_t write_wait;
174
175 char* interrupt_in_buffer;
176 struct usb_endpoint_descriptor* interrupt_in_endpoint;
177 struct urb* interrupt_in_urb;
178 int interrupt_in_interval;
179 size_t interrupt_in_endpoint_size;
180 int interrupt_in_running;
181 int interrupt_in_done;
9d33efd9
ON		 182 int buffer_overflow;
183 spinlock_t rbsl;
2824bd25
MH		 184
185 char* interrupt_out_buffer;
186 struct usb_endpoint_descriptor* interrupt_out_endpoint;
187 struct urb* interrupt_out_urb;
188 int interrupt_out_interval;
189 size_t interrupt_out_endpoint_size;
190 int interrupt_out_busy;
191};
192
2824bd25
MH		 193static struct usb_driver ld_usb_driver;
194
195/**
196 * ld_usb_abort_transfers
197 * aborts transfers and frees associated data structures
198 */
199static void ld_usb_abort_transfers(struct ld_usb *dev)
200{
201 /* shutdown transfer */
202 if (dev->interrupt_in_running) {
203 dev->interrupt_in_running = 0;
204 if (dev->intf)
205 usb_kill_urb(dev->interrupt_in_urb);
206 }
207 if (dev->interrupt_out_busy)
208 if (dev->intf)
209 usb_kill_urb(dev->interrupt_out_urb);
210}
211
212/**
213 * ld_usb_delete
214 */
215static void ld_usb_delete(struct ld_usb *dev)
216{
217 ld_usb_abort_transfers(dev);
218
219 /* free data structures */
220 usb_free_urb(dev->interrupt_in_urb);
221 usb_free_urb(dev->interrupt_out_urb);
222 kfree(dev->ring_buffer);
223 kfree(dev->interrupt_in_buffer);
224 kfree(dev->interrupt_out_buffer);
225 kfree(dev);
226}
227
228/**
229 * ld_usb_interrupt_in_callback
230 */
7d12e780 231static void ld_usb_interrupt_in_callback(struct urb *urb)
2824bd25
MH		 232{
233 struct ld_usb *dev = urb->context;
234 size_t *actual_buffer;
235 unsigned int next_ring_head;
491c021e 236 int status = urb->status;
2824bd25
MH		 237 int retval;
238
491c021e
GKH		 239 if (status) {
240 if (status == -ENOENT ||
241 status == -ECONNRESET ||
242 status == -ESHUTDOWN) {
2824bd25
MH		 243 goto exit;
244 } else {
457163c4
GKH		 245 dev_dbg(&dev->intf->dev,
246 "%s: nonzero status received: %d\n", __func__,
247 status);
9d33efd9 248 spin_lock(&dev->rbsl);
2824bd25
MH		 249 goto resubmit; /* maybe we can recover */
250 }
251 }
252
9d33efd9 253 spin_lock(&dev->rbsl);
2824bd25
MH		 254 if (urb->actual_length > 0) {
255 next_ring_head = (dev->ring_head+1) % ring_buffer_size;
256 if (next_ring_head != dev->ring_tail) {
257 actual_buffer = (size_t*)(dev->ring_buffer + dev->ring_head*(sizeof(size_t)+dev->interrupt_in_endpoint_size));
258 /* actual_buffer gets urb->actual_length + interrupt_in_buffer */
259 *actual_buffer = urb->actual_length;
260 memcpy(actual_buffer+1, dev->interrupt_in_buffer, urb->actual_length);
261 dev->ring_head = next_ring_head;
457163c4
GKH		 262 dev_dbg(&dev->intf->dev, "%s: received %d bytes\n",
263 __func__, urb->actual_length);
9d33efd9 264 } else {
2824bd25
MH		 265 dev_warn(&dev->intf->dev,
266 "Ring buffer overflow, %d bytes dropped\n",
267 urb->actual_length);
9d33efd9
ON		 268 dev->buffer_overflow = 1;
269 }
2824bd25
MH		 270 }
271
272resubmit:
273 /* resubmit if we're still running */
9d33efd9 274 if (dev->interrupt_in_running && !dev->buffer_overflow && dev->intf) {
2824bd25 275 retval = usb_submit_urb(dev->interrupt_in_urb, GFP_ATOMIC);
9d33efd9 276 if (retval) {
2824bd25
MH		 277 dev_err(&dev->intf->dev,
278 "usb_submit_urb failed (%d)\n", retval);
9d33efd9
ON		 279 dev->buffer_overflow = 1;
280 }
2824bd25 281 }
9d33efd9 282 spin_unlock(&dev->rbsl);
2824bd25
MH		 283exit:
284 dev->interrupt_in_done = 1;
285 wake_up_interruptible(&dev->read_wait);
286}
287
288/**
289 * ld_usb_interrupt_out_callback
290 */
7d12e780 291static void ld_usb_interrupt_out_callback(struct urb *urb)
2824bd25
MH		 292{
293 struct ld_usb *dev = urb->context;
491c021e 294 int status = urb->status;
2824bd25
MH		 295
296 /* sync/async unlink faults aren't errors */
491c021e
GKH		 297 if (status && !(status == -ENOENT ||
298 status == -ECONNRESET ||
299 status == -ESHUTDOWN))
457163c4
GKH		 300 dev_dbg(&dev->intf->dev,
301 "%s - nonzero write interrupt status received: %d\n",
302 __func__, status);
2824bd25
MH		 303
304 dev->interrupt_out_busy = 0;
305 wake_up_interruptible(&dev->write_wait);
306}
307
308/**
309 * ld_usb_open
310 */
311static int ld_usb_open(struct inode *inode, struct file *file)
312{
313 struct ld_usb *dev;
314 int subminor;
d4ead16f 315 int retval;
2824bd25
MH		 316 struct usb_interface *interface;
317
318 nonseekable_open(inode, file);
319 subminor = iminor(inode);
320
2824bd25
MH		 321 interface = usb_find_interface(&ld_usb_driver, subminor);
322
323 if (!interface) {
b22862e5
GKH		 324 printk(KERN_ERR "%s - error, can't find device for minor %d\n",
325 __func__, subminor);
d4ead16f 326 return -ENODEV;
2824bd25
MH		 327 }
328
329 dev = usb_get_intfdata(interface);
330
6248c52f 331 if (!dev)
d4ead16f 332 return -ENODEV;
2824bd25
MH		 333
334 /* lock this device */
6248c52f 335 if (mutex_lock_interruptible(&dev->mutex))
d4ead16f 336 return -ERESTARTSYS;
2824bd25
MH		 337
338 /* allow opening only once */
339 if (dev->open_count) {
340 retval = -EBUSY;
341 goto unlock_exit;
342 }
343 dev->open_count = 1;
344
345 /* initialize in direction */
346 dev->ring_head = 0;
347 dev->ring_tail = 0;
9d33efd9 348 dev->buffer_overflow = 0;
2824bd25
MH		 349 usb_fill_int_urb(dev->interrupt_in_urb,
350 interface_to_usbdev(interface),
351 usb_rcvintpipe(interface_to_usbdev(interface),
352 dev->interrupt_in_endpoint->bEndpointAddress),
353 dev->interrupt_in_buffer,
354 dev->interrupt_in_endpoint_size,
355 ld_usb_interrupt_in_callback,
356 dev,
357 dev->interrupt_in_interval);
358
359 dev->interrupt_in_running = 1;
360 dev->interrupt_in_done = 0;
361
362 retval = usb_submit_urb(dev->interrupt_in_urb, GFP_KERNEL);
363 if (retval) {
364 dev_err(&interface->dev, "Couldn't submit interrupt_in_urb %d\n", retval);
365 dev->interrupt_in_running = 0;
366 dev->open_count = 0;
367 goto unlock_exit;
368 }
369
370 /* save device in the file's private structure */
371 file->private_data = dev;
372
373unlock_exit:
ce0d7d3f 374 mutex_unlock(&dev->mutex);
2824bd25 375
2824bd25
MH		 376 return retval;
377}
378
379/**
380 * ld_usb_release
381 */
382static int ld_usb_release(struct inode *inode, struct file *file)
383{
384 struct ld_usb *dev;
385 int retval = 0;
386
387 dev = file->private_data;
388
389 if (dev == NULL) {
390 retval = -ENODEV;
391 goto exit;
392 }
393
ce0d7d3f 394 if (mutex_lock_interruptible(&dev->mutex)) {
2824bd25
MH		 395 retval = -ERESTARTSYS;
396 goto exit;
397 }
398
399 if (dev->open_count != 1) {
400 retval = -ENODEV;
401 goto unlock_exit;
402 }
403 if (dev->intf == NULL) {
404 /* the device was unplugged before the file was released */
ce0d7d3f 405 mutex_unlock(&dev->mutex);
2824bd25
MH		 406 /* unlock here as ld_usb_delete frees dev */
407 ld_usb_delete(dev);
408 goto exit;
409 }
410
411 /* wait until write transfer is finished */
412 if (dev->interrupt_out_busy)
413 wait_event_interruptible_timeout(dev->write_wait, !dev->interrupt_out_busy, 2 * HZ);
414 ld_usb_abort_transfers(dev);
415 dev->open_count = 0;
416
417unlock_exit:
ce0d7d3f 418 mutex_unlock(&dev->mutex);
2824bd25
MH		 419
420exit:
421 return retval;
422}
423
424/**
425 * ld_usb_poll
426 */
427static unsigned int ld_usb_poll(struct file *file, poll_table *wait)
428{
429 struct ld_usb *dev;
430 unsigned int mask = 0;
431
432 dev = file->private_data;
433
d12b85e7
ON		 434 if (!dev->intf)
435 return POLLERR | POLLHUP;
436
2824bd25
MH		 437 poll_wait(file, &dev->read_wait, wait);
438 poll_wait(file, &dev->write_wait, wait);
439
440 if (dev->ring_head != dev->ring_tail)
441 mask |= POLLIN | POLLRDNORM;
442 if (!dev->interrupt_out_busy)
443 mask |= POLLOUT | POLLWRNORM;
444
445 return mask;
446}
447
448/**
449 * ld_usb_read
450 */
451static ssize_t ld_usb_read(struct file *file, char __user *buffer, size_t count,
452 loff_t *ppos)
453{
454 struct ld_usb *dev;
455 size_t *actual_buffer;
456 size_t bytes_to_read;
457 int retval = 0;
9d33efd9 458 int rv;
2824bd25
MH		 459
460 dev = file->private_data;
461
462 /* verify that we actually have some data to read */
463 if (count == 0)
464 goto exit;
465
466 /* lock this object */
ce0d7d3f 467 if (mutex_lock_interruptible(&dev->mutex)) {
2824bd25
MH		 468 retval = -ERESTARTSYS;
469 goto exit;
470 }
471
472 /* verify that the device wasn't unplugged */
473 if (dev->intf == NULL) {
474 retval = -ENODEV;
b22862e5 475 printk(KERN_ERR "ldusb: No device or device unplugged %d\n", retval);
2824bd25
MH		 476 goto unlock_exit;
477 }
478
479 /* wait for data */
9d33efd9 480 spin_lock_irq(&dev->rbsl);
2824bd25 481 if (dev->ring_head == dev->ring_tail) {
9d33efd9
ON		 482 dev->interrupt_in_done = 0;
483 spin_unlock_irq(&dev->rbsl);
2824bd25
MH		 484 if (file->f_flags & O_NONBLOCK) {
485 retval = -EAGAIN;
486 goto unlock_exit;
487 }
488 retval = wait_event_interruptible(dev->read_wait, dev->interrupt_in_done);
489 if (retval < 0)
490 goto unlock_exit;
9d33efd9
ON		 491 } else {
492 spin_unlock_irq(&dev->rbsl);
2824bd25
MH		 493 }
494
495 /* actual_buffer contains actual_length + interrupt_in_buffer */
496 actual_buffer = (size_t*)(dev->ring_buffer + dev->ring_tail*(sizeof(size_t)+dev->interrupt_in_endpoint_size));
497 bytes_to_read = min(count, *actual_buffer);
498 if (bytes_to_read < *actual_buffer)
dd7d5008 499 dev_warn(&dev->intf->dev, "Read buffer overflow, %zd bytes dropped\n",
2824bd25
MH		 500 *actual_buffer-bytes_to_read);
501
502 /* copy one interrupt_in_buffer from ring_buffer into userspace */
503 if (copy_to_user(buffer, actual_buffer+1, bytes_to_read)) {
504 retval = -EFAULT;
505 goto unlock_exit;
506 }
507 dev->ring_tail = (dev->ring_tail+1) % ring_buffer_size;
508
509 retval = bytes_to_read;
510
9d33efd9
ON		 511 spin_lock_irq(&dev->rbsl);
512 if (dev->buffer_overflow) {
513 dev->buffer_overflow = 0;
514 spin_unlock_irq(&dev->rbsl);
515 rv = usb_submit_urb(dev->interrupt_in_urb, GFP_KERNEL);
516 if (rv < 0)
517 dev->buffer_overflow = 1;
518 } else {
519 spin_unlock_irq(&dev->rbsl);
520 }
521
2824bd25
MH		 522unlock_exit:
523 /* unlock the device */
ce0d7d3f 524 mutex_unlock(&dev->mutex);
2824bd25
MH		 525
526exit:
527 return retval;
528}
529
530/**
531 * ld_usb_write
532 */
533static ssize_t ld_usb_write(struct file *file, const char __user *buffer,
534 size_t count, loff_t *ppos)
535{
536 struct ld_usb *dev;
537 size_t bytes_to_write;
538 int retval = 0;
539
540 dev = file->private_data;
541
542 /* verify that we actually have some data to write */
543 if (count == 0)
544 goto exit;
545
546 /* lock this object */
ce0d7d3f 547 if (mutex_lock_interruptible(&dev->mutex)) {
2824bd25
MH		 548 retval = -ERESTARTSYS;
549 goto exit;
550 }
551
552 /* verify that the device wasn't unplugged */
553 if (dev->intf == NULL) {
554 retval = -ENODEV;
b22862e5 555 printk(KERN_ERR "ldusb: No device or device unplugged %d\n", retval);
2824bd25
MH		 556 goto unlock_exit;
557 }
558
559 /* wait until previous transfer is finished */
560 if (dev->interrupt_out_busy) {
561 if (file->f_flags & O_NONBLOCK) {
562 retval = -EAGAIN;
563 goto unlock_exit;
564 }
565 retval = wait_event_interruptible(dev->write_wait, !dev->interrupt_out_busy);
566 if (retval < 0) {
567 goto unlock_exit;
568 }
569 }
570
571 /* write the data into interrupt_out_buffer from userspace */
572 bytes_to_write = min(count, write_buffer_size*dev->interrupt_out_endpoint_size);
573 if (bytes_to_write < count)
dd7d5008 574 dev_warn(&dev->intf->dev, "Write buffer overflow, %zd bytes dropped\n",count-bytes_to_write);
457163c4
GKH		 575 dev_dbg(&dev->intf->dev, "%s: count = %zd, bytes_to_write = %zd\n",
576 __func__, count, bytes_to_write);
2824bd25
MH		 577
578 if (copy_from_user(dev->interrupt_out_buffer, buffer, bytes_to_write)) {
579 retval = -EFAULT;
580 goto unlock_exit;
581 }
582
583 if (dev->interrupt_out_endpoint == NULL) {
584 /* try HID_REQ_SET_REPORT=9 on control_endpoint instead of interrupt_out_endpoint */
585 retval = usb_control_msg(interface_to_usbdev(dev->intf),
586 usb_sndctrlpipe(interface_to_usbdev(dev->intf), 0),
587 9,
588 USB_TYPE_CLASS | USB_RECIP_INTERFACE | USB_DIR_OUT,
589 1 << 8, 0,
590 dev->interrupt_out_buffer,
591 bytes_to_write,
592 USB_CTRL_SET_TIMEOUT * HZ);
593 if (retval < 0)
b22862e5
GKH		 594 dev_err(&dev->intf->dev,
595 "Couldn't submit HID_REQ_SET_REPORT %d\n",
596 retval);
2824bd25
MH		 597 goto unlock_exit;
598 }
599
600 /* send off the urb */
601 usb_fill_int_urb(dev->interrupt_out_urb,
602 interface_to_usbdev(dev->intf),
603 usb_sndintpipe(interface_to_usbdev(dev->intf),
604 dev->interrupt_out_endpoint->bEndpointAddress),
605 dev->interrupt_out_buffer,
606 bytes_to_write,
607 ld_usb_interrupt_out_callback,
608 dev,
609 dev->interrupt_out_interval);
610
611 dev->interrupt_out_busy = 1;
612 wmb();
613
614 retval = usb_submit_urb(dev->interrupt_out_urb, GFP_KERNEL);
615 if (retval) {
616 dev->interrupt_out_busy = 0;
b22862e5
GKH		 617 dev_err(&dev->intf->dev,
618 "Couldn't submit interrupt_out_urb %d\n", retval);
2824bd25
MH		 619 goto unlock_exit;
620 }
621 retval = bytes_to_write;
622
623unlock_exit:
624 /* unlock the device */
ce0d7d3f 625 mutex_unlock(&dev->mutex);
2824bd25
MH		 626
627exit:
628 return retval;
629}
630
631/* file operations needed when we register this driver */
066202dd 632static const struct file_operations ld_usb_fops = {
2824bd25
MH		 633 .owner = THIS_MODULE,
634 .read = ld_usb_read,
635 .write = ld_usb_write,
636 .open = ld_usb_open,
637 .release = ld_usb_release,
638 .poll = ld_usb_poll,
6038f373 639 .llseek = no_llseek,
2824bd25
MH		 640};
641
642/*
643 * usb class driver info in order to get a minor number from the usb core,
595b14cb 644 * and to have the device registered with the driver core
2824bd25
MH		 645 */
646static struct usb_class_driver ld_usb_class = {
647 .name = "ldusb%d",
648 .fops = &ld_usb_fops,
649 .minor_base = USB_LD_MINOR_BASE,
650};
651
652/**
653 * ld_usb_probe
654 *
655 * Called by the usb core when a new device is connected that it thinks
656 * this driver might be interested in.
657 */
658static int ld_usb_probe(struct usb_interface *intf, const struct usb_device_id *id)
659{
660 struct usb_device *udev = interface_to_usbdev(intf);
661 struct ld_usb *dev = NULL;
662 struct usb_host_interface *iface_desc;
663 struct usb_endpoint_descriptor *endpoint;
664 char *buffer;
665 int i;
666 int retval = -ENOMEM;
667
b595076a 668 /* allocate memory for our device state and initialize it */
2824bd25 669
1144cf7a 670 dev = kzalloc(sizeof(*dev), GFP_KERNEL);
2824bd25
MH		 671 if (dev == NULL) {
672 dev_err(&intf->dev, "Out of memory\n");
673 goto exit;
674 }
ce0d7d3f 675 mutex_init(&dev->mutex);
9d33efd9 676 spin_lock_init(&dev->rbsl);
2824bd25
MH		 677 dev->intf = intf;
678 init_waitqueue_head(&dev->read_wait);
679 init_waitqueue_head(&dev->write_wait);
680
681 /* workaround for early firmware versions on fast computers */
682 if ((le16_to_cpu(udev->descriptor.idVendor) == USB_VENDOR_ID_LD) &&
ba3e66e9
MH		 683 ((le16_to_cpu(udev->descriptor.idProduct) == USB_DEVICE_ID_LD_CASSY) ||
684 (le16_to_cpu(udev->descriptor.idProduct) == USB_DEVICE_ID_LD_COM3LAB)) &&
2824bd25
MH		 685 (le16_to_cpu(udev->descriptor.bcdDevice) <= 0x103)) {
686 buffer = kmalloc(256, GFP_KERNEL);
a6db592e
MH		 687 if (buffer == NULL) {
688 dev_err(&intf->dev, "Couldn't allocate string buffer\n");
689 goto error;
690 }
2824bd25
MH		 691 /* usb_string makes SETUP+STALL to leave always ControlReadLoop */
692 usb_string(udev, 255, buffer, 256);
693 kfree(buffer);
694 }
695
696 iface_desc = intf->cur_altsetting;
697
698 /* set up the endpoint information */
699 for (i = 0; i < iface_desc->desc.bNumEndpoints; ++i) {
700 endpoint = &iface_desc->endpoint[i].desc;
701
5482687b 702 if (usb_endpoint_is_int_in(endpoint))
2824bd25 703 dev->interrupt_in_endpoint = endpoint;
2824bd25 704
5482687b 705 if (usb_endpoint_is_int_out(endpoint))
2824bd25 706 dev->interrupt_out_endpoint = endpoint;
2824bd25
MH		 707 }
708 if (dev->interrupt_in_endpoint == NULL) {
709 dev_err(&intf->dev, "Interrupt in endpoint not found\n");
710 goto error;
711 }
712 if (dev->interrupt_out_endpoint == NULL)
713 dev_warn(&intf->dev, "Interrupt out endpoint not found (using control endpoint instead)\n");
714
29cc8897 715 dev->interrupt_in_endpoint_size = usb_endpoint_maxp(dev->interrupt_in_endpoint);
2824bd25
MH		 716 dev->ring_buffer = kmalloc(ring_buffer_size*(sizeof(size_t)+dev->interrupt_in_endpoint_size), GFP_KERNEL);
717 if (!dev->ring_buffer) {
718 dev_err(&intf->dev, "Couldn't allocate ring_buffer\n");
719 goto error;
720 }
721 dev->interrupt_in_buffer = kmalloc(dev->interrupt_in_endpoint_size, GFP_KERNEL);
722 if (!dev->interrupt_in_buffer) {
723 dev_err(&intf->dev, "Couldn't allocate interrupt_in_buffer\n");
724 goto error;
725 }
726 dev->interrupt_in_urb = usb_alloc_urb(0, GFP_KERNEL);
727 if (!dev->interrupt_in_urb) {
728 dev_err(&intf->dev, "Couldn't allocate interrupt_in_urb\n");
729 goto error;
730 }
29cc8897 731 dev->interrupt_out_endpoint_size = dev->interrupt_out_endpoint ? usb_endpoint_maxp(dev->interrupt_out_endpoint) :
2824bd25
MH		 732 udev->descriptor.bMaxPacketSize0;
733 dev->interrupt_out_buffer = kmalloc(write_buffer_size*dev->interrupt_out_endpoint_size, GFP_KERNEL);
734 if (!dev->interrupt_out_buffer) {
735 dev_err(&intf->dev, "Couldn't allocate interrupt_out_buffer\n");
736 goto error;
737 }
738 dev->interrupt_out_urb = usb_alloc_urb(0, GFP_KERNEL);
739 if (!dev->interrupt_out_urb) {
740 dev_err(&intf->dev, "Couldn't allocate interrupt_out_urb\n");
741 goto error;
742 }
743 dev->interrupt_in_interval = min_interrupt_in_interval > dev->interrupt_in_endpoint->bInterval ? min_interrupt_in_interval : dev->interrupt_in_endpoint->bInterval;
744 if (dev->interrupt_out_endpoint)
745 dev->interrupt_out_interval = min_interrupt_out_interval > dev->interrupt_out_endpoint->bInterval ? min_interrupt_out_interval : dev->interrupt_out_endpoint->bInterval;
746
747 /* we can register the device now, as it is ready */
748 usb_set_intfdata(intf, dev);
749
750 retval = usb_register_dev(intf, &ld_usb_class);
751 if (retval) {
752 /* something prevented us from registering this driver */
753 dev_err(&intf->dev, "Not able to get a minor for this device.\n");
754 usb_set_intfdata(intf, NULL);
755 goto error;
756 }
757
758 /* let the user know what node this device is now attached to */
759 dev_info(&intf->dev, "LD USB Device #%d now attached to major %d minor %d\n",
760 (intf->minor - USB_LD_MINOR_BASE), USB_MAJOR, intf->minor);
761
762exit:
763 return retval;
764
765error:
766 ld_usb_delete(dev);
767
768 return retval;
769}
770
771/**
772 * ld_usb_disconnect
773 *
774 * Called by the usb core when the device is removed from the system.
775 */
776static void ld_usb_disconnect(struct usb_interface *intf)
777{
778 struct ld_usb *dev;
779 int minor;
780
2824bd25
MH		 781 dev = usb_get_intfdata(intf);
782 usb_set_intfdata(intf, NULL);
783
2824bd25
MH		 784 minor = intf->minor;
785
786 /* give back our minor */
787 usb_deregister_dev(intf, &ld_usb_class);
788
ce0d7d3f 789 mutex_lock(&dev->mutex);
d4ead16f 790
2824bd25
MH		 791 /* if the device is not opened, then we clean up right now */
792 if (!dev->open_count) {
ce0d7d3f 793 mutex_unlock(&dev->mutex);
2824bd25
MH		 794 ld_usb_delete(dev);
795 } else {
796 dev->intf = NULL;
d12b85e7
ON		 797 /* wake up pollers */
798 wake_up_interruptible_all(&dev->read_wait);
799 wake_up_interruptible_all(&dev->write_wait);
ce0d7d3f 800 mutex_unlock(&dev->mutex);
2824bd25
MH		 801 }
802
2824bd25
MH		 803 dev_info(&intf->dev, "LD USB Device #%d now disconnected\n",
804 (minor - USB_LD_MINOR_BASE));
805}
806
807/* usb specific object needed to register this driver with the usb subsystem */
808static struct usb_driver ld_usb_driver = {
2824bd25
MH		 809 .name = "ldusb",
810 .probe = ld_usb_probe,
811 .disconnect = ld_usb_disconnect,
812 .id_table = ld_usb_table,
813};
814
65db4305 815module_usb_driver(ld_usb_driver);
2824bd25 816
Linux 6.x block layer and io_uring tree(s)