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USB: usbtmc: Fix short reads in usbtmc_read()
[linux-2.6-block.git] / drivers / usb / class / usbtmc.c
CommitLineData
5b775f67
GKH		 1/**
2 * drivers/usb/class/usbtmc.c - USB Test & Measurment class driver
3 *
4 * Copyright (C) 2007 Stefan Kopp, Gechingen, Germany
5 * Copyright (C) 2008 Novell, Inc.
6 * Copyright (C) 2008 Greg Kroah-Hartman <gregkh@suse.de>
7 *
8 * This program is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU General Public License
10 * as published by the Free Software Foundation; either version 2
11 * of the License, or (at your option) any later version.
12 *
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
17 *
18 * The GNU General Public License is available at
19 * http://www.gnu.org/copyleft/gpl.html.
20 */
21
22#include <linux/init.h>
23#include <linux/module.h>
857cc4df 24#include <linux/kernel.h>
5b775f67
GKH		 25#include <linux/fs.h>
26#include <linux/uaccess.h>
27#include <linux/kref.h>
28#include <linux/mutex.h>
29#include <linux/usb.h>
30#include <linux/usb/tmc.h>
31
32
33#define USBTMC_MINOR_BASE 176
34
35/*
36 * Size of driver internal IO buffer. Must be multiple of 4 and at least as
37 * large as wMaxPacketSize (which is usually 512 bytes).
38 */
39#define USBTMC_SIZE_IOBUFFER 2048
40
41/* Default USB timeout (in milliseconds) */
42#define USBTMC_TIMEOUT 10
43
44/*
45 * Maximum number of read cycles to empty bulk in endpoint during CLEAR and
46 * ABORT_BULK_IN requests. Ends the loop if (for whatever reason) a short
47 * packet is never read.
48 */
49#define USBTMC_MAX_READS_TO_CLEAR_BULK_IN 100
50
51static struct usb_device_id usbtmc_devices[] = {
52 { USB_INTERFACE_INFO(USB_CLASS_APP_SPEC, 3, 0), },
228dd05d 53 { USB_INTERFACE_INFO(USB_CLASS_APP_SPEC, 3, 1), },
5b775f67
GKH		 54 { 0, } /* terminating entry */
55};
5413aa46 56MODULE_DEVICE_TABLE(usb, usbtmc_devices);
5b775f67
GKH		 57
58/*
59 * This structure is the capabilities for the device
60 * See section 4.2.1.8 of the USBTMC specification for details.
61 */
62struct usbtmc_dev_capabilities {
63 __u8 interface_capabilities;
64 __u8 device_capabilities;
65 __u8 usb488_interface_capabilities;
66 __u8 usb488_device_capabilities;
67};
68
69/* This structure holds private data for each USBTMC device. One copy is
70 * allocated for each USBTMC device in the driver's probe function.
71 */
72struct usbtmc_device_data {
73 const struct usb_device_id *id;
74 struct usb_device *usb_dev;
75 struct usb_interface *intf;
76
77 unsigned int bulk_in;
78 unsigned int bulk_out;
79
80 u8 bTag;
81 u8 bTag_last_write; /* needed for abort */
82 u8 bTag_last_read; /* needed for abort */
83
84 /* attributes from the USB TMC spec for this device */
85 u8 TermChar;
86 bool TermCharEnabled;
87 bool auto_abort;
88
86286883
ON		 89 bool zombie; /* fd of disconnected device */
90
5b775f67
GKH		 91 struct usbtmc_dev_capabilities capabilities;
92 struct kref kref;
93 struct mutex io_mutex; /* only one i/o function running at a time */
94};
95#define to_usbtmc_data(d) container_of(d, struct usbtmc_device_data, kref)
96
97/* Forward declarations */
98static struct usb_driver usbtmc_driver;
99
100static void usbtmc_delete(struct kref *kref)
101{
102 struct usbtmc_device_data *data = to_usbtmc_data(kref);
103
104 usb_put_dev(data->usb_dev);
105 kfree(data);
106}
107
108static int usbtmc_open(struct inode *inode, struct file *filp)
109{
110 struct usb_interface *intf;
111 struct usbtmc_device_data *data;
5b10916e 112 int retval = 0;
5b775f67
GKH		 113
114 intf = usb_find_interface(&usbtmc_driver, iminor(inode));
115 if (!intf) {
116 printk(KERN_ERR KBUILD_MODNAME
117 ": can not find device for minor %d", iminor(inode));
5b10916e 118 retval = -ENODEV;
5b775f67
GKH		 119 goto exit;
120 }
121
122 data = usb_get_intfdata(intf);
123 kref_get(&data->kref);
124
125 /* Store pointer in file structure's private data field */
126 filp->private_data = data;
127
128exit:
129 return retval;
130}
131
132static int usbtmc_release(struct inode *inode, struct file *file)
133{
134 struct usbtmc_device_data *data = file->private_data;
135
136 kref_put(&data->kref, usbtmc_delete);
137 return 0;
138}
139
140static int usbtmc_ioctl_abort_bulk_in(struct usbtmc_device_data *data)
141{
b361a6e3 142 u8 *buffer;
5b775f67
GKH		 143 struct device *dev;
144 int rv;
145 int n;
146 int actual;
147 struct usb_host_interface *current_setting;
148 int max_size;
149
150 dev = &data->intf->dev;
151 buffer = kmalloc(USBTMC_SIZE_IOBUFFER, GFP_KERNEL);
152 if (!buffer)
153 return -ENOMEM;
154
155 rv = usb_control_msg(data->usb_dev,
156 usb_rcvctrlpipe(data->usb_dev, 0),
157 USBTMC_REQUEST_INITIATE_ABORT_BULK_IN,
158 USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_ENDPOINT,
159 data->bTag_last_read, data->bulk_in,
160 buffer, 2, USBTMC_TIMEOUT);
161
162 if (rv < 0) {
163 dev_err(dev, "usb_control_msg returned %d\n", rv);
164 goto exit;
165 }
166
167 dev_dbg(dev, "INITIATE_ABORT_BULK_IN returned %x\n", buffer[0]);
168
169 if (buffer[0] == USBTMC_STATUS_FAILED) {
170 rv = 0;
171 goto exit;
172 }
173
174 if (buffer[0] != USBTMC_STATUS_SUCCESS) {
175 dev_err(dev, "INITIATE_ABORT_BULK_IN returned %x\n",
176 buffer[0]);
177 rv = -EPERM;
178 goto exit;
179 }
180
181 max_size = 0;
182 current_setting = data->intf->cur_altsetting;
183 for (n = 0; n < current_setting->desc.bNumEndpoints; n++)
184 if (current_setting->endpoint[n].desc.bEndpointAddress ==
185 data->bulk_in)
186 max_size = le16_to_cpu(current_setting->endpoint[n].
187 desc.wMaxPacketSize);
188
189 if (max_size == 0) {
190 dev_err(dev, "Couldn't get wMaxPacketSize\n");
191 rv = -EPERM;
192 goto exit;
193 }
194
195 dev_dbg(&data->intf->dev, "wMaxPacketSize is %d\n", max_size);
196
197 n = 0;
198
199 do {
200 dev_dbg(dev, "Reading from bulk in EP\n");
201
202 rv = usb_bulk_msg(data->usb_dev,
203 usb_rcvbulkpipe(data->usb_dev,
204 data->bulk_in),
205 buffer, USBTMC_SIZE_IOBUFFER,
206 &actual, USBTMC_TIMEOUT);
207
208 n++;
209
210 if (rv < 0) {
211 dev_err(dev, "usb_bulk_msg returned %d\n", rv);
212 goto exit;
213 }
214 } while ((actual == max_size) &&
215 (n < USBTMC_MAX_READS_TO_CLEAR_BULK_IN));
216
217 if (actual == max_size) {
218 dev_err(dev, "Couldn't clear device buffer within %d cycles\n",
219 USBTMC_MAX_READS_TO_CLEAR_BULK_IN);
220 rv = -EPERM;
221 goto exit;
222 }
223
224 n = 0;
225
226usbtmc_abort_bulk_in_status:
227 rv = usb_control_msg(data->usb_dev,
228 usb_rcvctrlpipe(data->usb_dev, 0),
229 USBTMC_REQUEST_CHECK_ABORT_BULK_IN_STATUS,
230 USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_ENDPOINT,
231 0, data->bulk_in, buffer, 0x08,
232 USBTMC_TIMEOUT);
233
234 if (rv < 0) {
235 dev_err(dev, "usb_control_msg returned %d\n", rv);
236 goto exit;
237 }
238
239 dev_dbg(dev, "INITIATE_ABORT_BULK_IN returned %x\n", buffer[0]);
240
241 if (buffer[0] == USBTMC_STATUS_SUCCESS) {
242 rv = 0;
243 goto exit;
244 }
245
246 if (buffer[0] != USBTMC_STATUS_PENDING) {
247 dev_err(dev, "INITIATE_ABORT_BULK_IN returned %x\n", buffer[0]);
248 rv = -EPERM;
249 goto exit;
250 }
251
252 if (buffer[1] == 1)
253 do {
254 dev_dbg(dev, "Reading from bulk in EP\n");
255
256 rv = usb_bulk_msg(data->usb_dev,
257 usb_rcvbulkpipe(data->usb_dev,
258 data->bulk_in),
259 buffer, USBTMC_SIZE_IOBUFFER,
260 &actual, USBTMC_TIMEOUT);
261
262 n++;
263
264 if (rv < 0) {
265 dev_err(dev, "usb_bulk_msg returned %d\n", rv);
266 goto exit;
267 }
268 } while ((actual = max_size) &&
269 (n < USBTMC_MAX_READS_TO_CLEAR_BULK_IN));
270
271 if (actual == max_size) {
272 dev_err(dev, "Couldn't clear device buffer within %d cycles\n",
273 USBTMC_MAX_READS_TO_CLEAR_BULK_IN);
274 rv = -EPERM;
275 goto exit;
276 }
277
278 goto usbtmc_abort_bulk_in_status;
279
280exit:
281 kfree(buffer);
282 return rv;
283
284}
285
286static int usbtmc_ioctl_abort_bulk_out(struct usbtmc_device_data *data)
287{
288 struct device *dev;
289 u8 *buffer;
290 int rv;
291 int n;
292
293 dev = &data->intf->dev;
294
295 buffer = kmalloc(8, GFP_KERNEL);
296 if (!buffer)
297 return -ENOMEM;
298
299 rv = usb_control_msg(data->usb_dev,
300 usb_rcvctrlpipe(data->usb_dev, 0),
301 USBTMC_REQUEST_INITIATE_ABORT_BULK_OUT,
302 USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_ENDPOINT,
303 data->bTag_last_write, data->bulk_out,
304 buffer, 2, USBTMC_TIMEOUT);
305
306 if (rv < 0) {
307 dev_err(dev, "usb_control_msg returned %d\n", rv);
308 goto exit;
309 }
310
311 dev_dbg(dev, "INITIATE_ABORT_BULK_OUT returned %x\n", buffer[0]);
312
313 if (buffer[0] != USBTMC_STATUS_SUCCESS) {
314 dev_err(dev, "INITIATE_ABORT_BULK_OUT returned %x\n",
315 buffer[0]);
316 rv = -EPERM;
317 goto exit;
318 }
319
320 n = 0;
321
322usbtmc_abort_bulk_out_check_status:
323 rv = usb_control_msg(data->usb_dev,
324 usb_rcvctrlpipe(data->usb_dev, 0),
325 USBTMC_REQUEST_CHECK_ABORT_BULK_OUT_STATUS,
326 USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_ENDPOINT,
327 0, data->bulk_out, buffer, 0x08,
328 USBTMC_TIMEOUT);
329 n++;
330 if (rv < 0) {
331 dev_err(dev, "usb_control_msg returned %d\n", rv);
332 goto exit;
333 }
334
335 dev_dbg(dev, "CHECK_ABORT_BULK_OUT returned %x\n", buffer[0]);
336
337 if (buffer[0] == USBTMC_STATUS_SUCCESS)
338 goto usbtmc_abort_bulk_out_clear_halt;
339
340 if ((buffer[0] == USBTMC_STATUS_PENDING) &&
341 (n < USBTMC_MAX_READS_TO_CLEAR_BULK_IN))
342 goto usbtmc_abort_bulk_out_check_status;
343
344 rv = -EPERM;
345 goto exit;
346
347usbtmc_abort_bulk_out_clear_halt:
348 rv = usb_control_msg(data->usb_dev,
349 usb_sndctrlpipe(data->usb_dev, 0),
350 USB_REQ_CLEAR_FEATURE,
351 USB_DIR_OUT | USB_TYPE_STANDARD |
352 USB_RECIP_ENDPOINT,
353 USB_ENDPOINT_HALT, data->bulk_out, buffer,
354 0, USBTMC_TIMEOUT);
355
356 if (rv < 0) {
357 dev_err(dev, "usb_control_msg returned %d\n", rv);
358 goto exit;
359 }
360 rv = 0;
361
362exit:
363 kfree(buffer);
364 return rv;
365}
366
367static ssize_t usbtmc_read(struct file *filp, char __user *buf,
368 size_t count, loff_t *f_pos)
369{
370 struct usbtmc_device_data *data;
371 struct device *dev;
665d7662 372 u32 n_characters;
5b775f67
GKH		 373 u8 *buffer;
374 int actual;
665d7662
GS		 375 size_t done;
376 size_t remaining;
5b775f67 377 int retval;
665d7662 378 size_t this_part;
5b775f67
GKH		 379
380 /* Get pointer to private data structure */
381 data = filp->private_data;
382 dev = &data->intf->dev;
383
384 buffer = kmalloc(USBTMC_SIZE_IOBUFFER, GFP_KERNEL);
385 if (!buffer)
386 return -ENOMEM;
387
388 mutex_lock(&data->io_mutex);
86286883
ON		 389 if (data->zombie) {
390 retval = -ENODEV;
391 goto exit;
392 }
5b775f67
GKH		 393
394 remaining = count;
395 done = 0;
396
397 while (remaining > 0) {
398 if (remaining > USBTMC_SIZE_IOBUFFER - 12 - 3)
399 this_part = USBTMC_SIZE_IOBUFFER - 12 - 3;
400 else
401 this_part = remaining;
402
403 /* Setup IO buffer for DEV_DEP_MSG_IN message
404 * Refer to class specs for details
405 */
406 buffer[0] = 2;
407 buffer[1] = data->bTag;
408 buffer[2] = ~(data->bTag);
409 buffer[3] = 0; /* Reserved */
c2cd26e1
SH		 410 buffer[4] = (this_part) & 255;
411 buffer[5] = ((this_part) >> 8) & 255;
412 buffer[6] = ((this_part) >> 16) & 255;
413 buffer[7] = ((this_part) >> 24) & 255;
5b775f67
GKH		 414 buffer[8] = data->TermCharEnabled * 2;
415 /* Use term character? */
416 buffer[9] = data->TermChar;
417 buffer[10] = 0; /* Reserved */
418 buffer[11] = 0; /* Reserved */
419
420 /* Send bulk URB */
421 retval = usb_bulk_msg(data->usb_dev,
422 usb_sndbulkpipe(data->usb_dev,
423 data->bulk_out),
424 buffer, 12, &actual, USBTMC_TIMEOUT);
425
426 /* Store bTag (in case we need to abort) */
427 data->bTag_last_write = data->bTag;
428
429 /* Increment bTag -- and increment again if zero */
430 data->bTag++;
431 if (!data->bTag)
432 (data->bTag)++;
433
434 if (retval < 0) {
435 dev_err(dev, "usb_bulk_msg returned %d\n", retval);
436 if (data->auto_abort)
437 usbtmc_ioctl_abort_bulk_out(data);
438 goto exit;
439 }
440
441 /* Send bulk URB */
442 retval = usb_bulk_msg(data->usb_dev,
443 usb_rcvbulkpipe(data->usb_dev,
444 data->bulk_in),
445 buffer, USBTMC_SIZE_IOBUFFER, &actual,
446 USBTMC_TIMEOUT);
447
448 /* Store bTag (in case we need to abort) */
449 data->bTag_last_read = data->bTag;
450
451 if (retval < 0) {
452 dev_err(dev, "Unable to read data, error %d\n", retval);
453 if (data->auto_abort)
454 usbtmc_ioctl_abort_bulk_in(data);
455 goto exit;
456 }
457
458 /* How many characters did the instrument send? */
459 n_characters = buffer[4] +
460 (buffer[5] << 8) +
461 (buffer[6] << 16) +
462 (buffer[7] << 24);
463
665d7662
GS		 464 /* Ensure the instrument doesn't lie about it */
465 if(n_characters > actual - 12) {
a2fbf10e 466 dev_err(dev, "Device lies about message size: %u > %d\n", n_characters, actual - 12);
665d7662
GS		 467 n_characters = actual - 12;
468 }
469
470 /* Ensure the instrument doesn't send more back than requested */
471 if(n_characters > this_part) {
472 dev_err(dev, "Device returns more than requested: %zu > %zu\n", done + n_characters, done + this_part);
473 n_characters = this_part;
474 }
475
5b775f67
GKH		 476 /* Copy buffer to user space */
477 if (copy_to_user(buf + done, &buffer[12], n_characters)) {
478 /* There must have been an addressing problem */
479 retval = -EFAULT;
480 goto exit;
481 }
482
483 done += n_characters;
484 if (n_characters < USBTMC_SIZE_IOBUFFER)
485 remaining = 0;
665d7662
GS		 486 else
487 remaining -= n_characters;
5b775f67
GKH		 488 }
489
490 /* Update file position value */
491 *f_pos = *f_pos + done;
492 retval = done;
493
494exit:
495 mutex_unlock(&data->io_mutex);
496 kfree(buffer);
497 return retval;
498}
499
500static ssize_t usbtmc_write(struct file *filp, const char __user *buf,
501 size_t count, loff_t *f_pos)
502{
503 struct usbtmc_device_data *data;
504 u8 *buffer;
505 int retval;
506 int actual;
507 unsigned long int n_bytes;
5b775f67
GKH		 508 int remaining;
509 int done;
510 int this_part;
511
512 data = filp->private_data;
513
514 buffer = kmalloc(USBTMC_SIZE_IOBUFFER, GFP_KERNEL);
515 if (!buffer)
516 return -ENOMEM;
517
518 mutex_lock(&data->io_mutex);
86286883
ON		 519 if (data->zombie) {
520 retval = -ENODEV;
521 goto exit;
522 }
5b775f67
GKH		 523
524 remaining = count;
525 done = 0;
526
527 while (remaining > 0) {
528 if (remaining > USBTMC_SIZE_IOBUFFER - 12) {
529 this_part = USBTMC_SIZE_IOBUFFER - 12;
530 buffer[8] = 0;
531 } else {
532 this_part = remaining;
533 buffer[8] = 1;
534 }
535
536 /* Setup IO buffer for DEV_DEP_MSG_OUT message */
537 buffer[0] = 1;
538 buffer[1] = data->bTag;
539 buffer[2] = ~(data->bTag);
540 buffer[3] = 0; /* Reserved */
541 buffer[4] = this_part & 255;
542 buffer[5] = (this_part >> 8) & 255;
543 buffer[6] = (this_part >> 16) & 255;
544 buffer[7] = (this_part >> 24) & 255;
545 /* buffer[8] is set above... */
546 buffer[9] = 0; /* Reserved */
547 buffer[10] = 0; /* Reserved */
548 buffer[11] = 0; /* Reserved */
549
550 if (copy_from_user(&buffer[12], buf + done, this_part)) {
551 retval = -EFAULT;
552 goto exit;
553 }
554
857cc4df
IJ		 555 n_bytes = roundup(12 + this_part, 4);
556 memset(buffer + 12 + this_part, 0, n_bytes - (12 + this_part));
5b775f67
GKH		 557
558 retval = usb_bulk_msg(data->usb_dev,
559 usb_sndbulkpipe(data->usb_dev,
560 data->bulk_out),
561 buffer, n_bytes, &actual, USBTMC_TIMEOUT);
562
563 data->bTag_last_write = data->bTag;
564 data->bTag++;
565
566 if (!data->bTag)
567 data->bTag++;
568
569 if (retval < 0) {
570 dev_err(&data->intf->dev,
571 "Unable to send data, error %d\n", retval);
572 if (data->auto_abort)
573 usbtmc_ioctl_abort_bulk_out(data);
574 goto exit;
575 }
576
577 remaining -= this_part;
578 done += this_part;
579 }
580
581 retval = count;
582exit:
583 mutex_unlock(&data->io_mutex);
584 kfree(buffer);
585 return retval;
586}
587
588static int usbtmc_ioctl_clear(struct usbtmc_device_data *data)
589{
590 struct usb_host_interface *current_setting;
591 struct usb_endpoint_descriptor *desc;
592 struct device *dev;
593 u8 *buffer;
594 int rv;
595 int n;
596 int actual;
597 int max_size;
598
599 dev = &data->intf->dev;
600
601 dev_dbg(dev, "Sending INITIATE_CLEAR request\n");
602
603 buffer = kmalloc(USBTMC_SIZE_IOBUFFER, GFP_KERNEL);
604 if (!buffer)
605 return -ENOMEM;
606
607 rv = usb_control_msg(data->usb_dev,
608 usb_rcvctrlpipe(data->usb_dev, 0),
609 USBTMC_REQUEST_INITIATE_CLEAR,
610 USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE,
611 0, 0, buffer, 1, USBTMC_TIMEOUT);
612 if (rv < 0) {
613 dev_err(dev, "usb_control_msg returned %d\n", rv);
614 goto exit;
615 }
616
617 dev_dbg(dev, "INITIATE_CLEAR returned %x\n", buffer[0]);
618
619 if (buffer[0] != USBTMC_STATUS_SUCCESS) {
620 dev_err(dev, "INITIATE_CLEAR returned %x\n", buffer[0]);
621 rv = -EPERM;
622 goto exit;
623 }
624
625 max_size = 0;
626 current_setting = data->intf->cur_altsetting;
627 for (n = 0; n < current_setting->desc.bNumEndpoints; n++) {
628 desc = &current_setting->endpoint[n].desc;
629 if (desc->bEndpointAddress == data->bulk_in)
630 max_size = le16_to_cpu(desc->wMaxPacketSize);
631 }
632
633 if (max_size == 0) {
634 dev_err(dev, "Couldn't get wMaxPacketSize\n");
635 rv = -EPERM;
636 goto exit;
637 }
638
639 dev_dbg(dev, "wMaxPacketSize is %d\n", max_size);
640
641 n = 0;
642
643usbtmc_clear_check_status:
644
645 dev_dbg(dev, "Sending CHECK_CLEAR_STATUS request\n");
646
647 rv = usb_control_msg(data->usb_dev,
648 usb_rcvctrlpipe(data->usb_dev, 0),
649 USBTMC_REQUEST_CHECK_CLEAR_STATUS,
650 USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE,
651 0, 0, buffer, 2, USBTMC_TIMEOUT);
652 if (rv < 0) {
653 dev_err(dev, "usb_control_msg returned %d\n", rv);
654 goto exit;
655 }
656
657 dev_dbg(dev, "CHECK_CLEAR_STATUS returned %x\n", buffer[0]);
658
659 if (buffer[0] == USBTMC_STATUS_SUCCESS)
660 goto usbtmc_clear_bulk_out_halt;
661
662 if (buffer[0] != USBTMC_STATUS_PENDING) {
663 dev_err(dev, "CHECK_CLEAR_STATUS returned %x\n", buffer[0]);
664 rv = -EPERM;
665 goto exit;
666 }
667
668 if (buffer[1] == 1)
669 do {
670 dev_dbg(dev, "Reading from bulk in EP\n");
671
672 rv = usb_bulk_msg(data->usb_dev,
673 usb_rcvbulkpipe(data->usb_dev,
674 data->bulk_in),
675 buffer, USBTMC_SIZE_IOBUFFER,
676 &actual, USBTMC_TIMEOUT);
677 n++;
678
679 if (rv < 0) {
680 dev_err(dev, "usb_control_msg returned %d\n",
681 rv);
682 goto exit;
683 }
684 } while ((actual == max_size) &&
685 (n < USBTMC_MAX_READS_TO_CLEAR_BULK_IN));
686
687 if (actual == max_size) {
688 dev_err(dev, "Couldn't clear device buffer within %d cycles\n",
689 USBTMC_MAX_READS_TO_CLEAR_BULK_IN);
690 rv = -EPERM;
691 goto exit;
692 }
693
694 goto usbtmc_clear_check_status;
695
696usbtmc_clear_bulk_out_halt:
697
698 rv = usb_control_msg(data->usb_dev,
699 usb_sndctrlpipe(data->usb_dev, 0),
700 USB_REQ_CLEAR_FEATURE,
701 USB_DIR_OUT | USB_TYPE_STANDARD |
702 USB_RECIP_ENDPOINT,
703 USB_ENDPOINT_HALT,
704 data->bulk_out, buffer, 0,
705 USBTMC_TIMEOUT);
706 if (rv < 0) {
707 dev_err(dev, "usb_control_msg returned %d\n", rv);
708 goto exit;
709 }
710 rv = 0;
711
712exit:
713 kfree(buffer);
714 return rv;
715}
716
717static int usbtmc_ioctl_clear_out_halt(struct usbtmc_device_data *data)
718{
719 u8 *buffer;
720 int rv;
721
722 buffer = kmalloc(2, GFP_KERNEL);
723 if (!buffer)
724 return -ENOMEM;
725
726 rv = usb_control_msg(data->usb_dev,
727 usb_sndctrlpipe(data->usb_dev, 0),
728 USB_REQ_CLEAR_FEATURE,
729 USB_DIR_OUT | USB_TYPE_STANDARD |
730 USB_RECIP_ENDPOINT,
731 USB_ENDPOINT_HALT, data->bulk_out,
732 buffer, 0, USBTMC_TIMEOUT);
733
734 if (rv < 0) {
735 dev_err(&data->usb_dev->dev, "usb_control_msg returned %d\n",
736 rv);
737 goto exit;
738 }
739 rv = 0;
740
741exit:
742 kfree(buffer);
743 return rv;
744}
745
746static int usbtmc_ioctl_clear_in_halt(struct usbtmc_device_data *data)
747{
748 u8 *buffer;
749 int rv;
750
751 buffer = kmalloc(2, GFP_KERNEL);
752 if (!buffer)
753 return -ENOMEM;
754
755 rv = usb_control_msg(data->usb_dev, usb_sndctrlpipe(data->usb_dev, 0),
756 USB_REQ_CLEAR_FEATURE,
757 USB_DIR_OUT | USB_TYPE_STANDARD |
758 USB_RECIP_ENDPOINT,
759 USB_ENDPOINT_HALT, data->bulk_in, buffer, 0,
760 USBTMC_TIMEOUT);
761
762 if (rv < 0) {
763 dev_err(&data->usb_dev->dev, "usb_control_msg returned %d\n",
764 rv);
765 goto exit;
766 }
767 rv = 0;
768
769exit:
770 kfree(buffer);
771 return rv;
772}
773
774static int get_capabilities(struct usbtmc_device_data *data)
775{
776 struct device *dev = &data->usb_dev->dev;
777 char *buffer;
ca157c4a 778 int rv = 0;
5b775f67
GKH		 779
780 buffer = kmalloc(0x18, GFP_KERNEL);
781 if (!buffer)
782 return -ENOMEM;
783
784 rv = usb_control_msg(data->usb_dev, usb_rcvctrlpipe(data->usb_dev, 0),
785 USBTMC_REQUEST_GET_CAPABILITIES,
786 USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE,
787 0, 0, buffer, 0x18, USBTMC_TIMEOUT);
788 if (rv < 0) {
789 dev_err(dev, "usb_control_msg returned %d\n", rv);
ca157c4a 790 goto err_out;
5b775f67
GKH		 791 }
792
793 dev_dbg(dev, "GET_CAPABILITIES returned %x\n", buffer[0]);
794 dev_dbg(dev, "Interface capabilities are %x\n", buffer[4]);
795 dev_dbg(dev, "Device capabilities are %x\n", buffer[5]);
796 dev_dbg(dev, "USB488 interface capabilities are %x\n", buffer[14]);
797 dev_dbg(dev, "USB488 device capabilities are %x\n", buffer[15]);
798 if (buffer[0] != USBTMC_STATUS_SUCCESS) {
799 dev_err(dev, "GET_CAPABILITIES returned %x\n", buffer[0]);
ca157c4a
ON		 800 rv = -EPERM;
801 goto err_out;
5b775f67
GKH		 802 }
803
804 data->capabilities.interface_capabilities = buffer[4];
805 data->capabilities.device_capabilities = buffer[5];
806 data->capabilities.usb488_interface_capabilities = buffer[14];
807 data->capabilities.usb488_device_capabilities = buffer[15];
808
ca157c4a 809err_out:
5b775f67 810 kfree(buffer);
ca157c4a 811 return rv;
5b775f67
GKH		 812}
813
814#define capability_attribute(name) \
815static ssize_t show_##name(struct device *dev, \
816 struct device_attribute *attr, char *buf) \
817{ \
818 struct usb_interface *intf = to_usb_interface(dev); \
819 struct usbtmc_device_data *data = usb_get_intfdata(intf); \
820 \
821 return sprintf(buf, "%d\n", data->capabilities.name); \
822} \
823static DEVICE_ATTR(name, S_IRUGO, show_##name, NULL)
824
825capability_attribute(interface_capabilities);
826capability_attribute(device_capabilities);
827capability_attribute(usb488_interface_capabilities);
828capability_attribute(usb488_device_capabilities);
829
830static struct attribute *capability_attrs[] = {
831 &dev_attr_interface_capabilities.attr,
832 &dev_attr_device_capabilities.attr,
833 &dev_attr_usb488_interface_capabilities.attr,
834 &dev_attr_usb488_device_capabilities.attr,
835 NULL,
836};
837
838static struct attribute_group capability_attr_grp = {
839 .attrs = capability_attrs,
840};
841
842static ssize_t show_TermChar(struct device *dev,
843 struct device_attribute *attr, char *buf)
844{
845 struct usb_interface *intf = to_usb_interface(dev);
846 struct usbtmc_device_data *data = usb_get_intfdata(intf);
847
848 return sprintf(buf, "%c\n", data->TermChar);
849}
850
851static ssize_t store_TermChar(struct device *dev,
852 struct device_attribute *attr,
853 const char *buf, size_t count)
854{
855 struct usb_interface *intf = to_usb_interface(dev);
856 struct usbtmc_device_data *data = usb_get_intfdata(intf);
857
858 if (count < 1)
859 return -EINVAL;
860 data->TermChar = buf[0];
861 return count;
862}
863static DEVICE_ATTR(TermChar, S_IRUGO, show_TermChar, store_TermChar);
864
865#define data_attribute(name) \
866static ssize_t show_##name(struct device *dev, \
867 struct device_attribute *attr, char *buf) \
868{ \
869 struct usb_interface *intf = to_usb_interface(dev); \
870 struct usbtmc_device_data *data = usb_get_intfdata(intf); \
871 \
872 return sprintf(buf, "%d\n", data->name); \
873} \
874static ssize_t store_##name(struct device *dev, \
875 struct device_attribute *attr, \
876 const char *buf, size_t count) \
877{ \
878 struct usb_interface *intf = to_usb_interface(dev); \
879 struct usbtmc_device_data *data = usb_get_intfdata(intf); \
880 ssize_t result; \
881 unsigned val; \
882 \
883 result = sscanf(buf, "%u\n", &val); \
884 if (result != 1) \
885 result = -EINVAL; \
886 data->name = val; \
887 if (result < 0) \
888 return result; \
889 else \
890 return count; \
891} \
892static DEVICE_ATTR(name, S_IRUGO, show_##name, store_##name)
893
894data_attribute(TermCharEnabled);
895data_attribute(auto_abort);
896
897static struct attribute *data_attrs[] = {
898 &dev_attr_TermChar.attr,
899 &dev_attr_TermCharEnabled.attr,
900 &dev_attr_auto_abort.attr,
901 NULL,
902};
903
904static struct attribute_group data_attr_grp = {
905 .attrs = data_attrs,
906};
907
908static int usbtmc_ioctl_indicator_pulse(struct usbtmc_device_data *data)
909{
910 struct device *dev;
911 u8 *buffer;
912 int rv;
913
914 dev = &data->intf->dev;
915
916 buffer = kmalloc(2, GFP_KERNEL);
917 if (!buffer)
918 return -ENOMEM;
919
920 rv = usb_control_msg(data->usb_dev,
921 usb_rcvctrlpipe(data->usb_dev, 0),
922 USBTMC_REQUEST_INDICATOR_PULSE,
923 USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE,
924 0, 0, buffer, 0x01, USBTMC_TIMEOUT);
925
926 if (rv < 0) {
927 dev_err(dev, "usb_control_msg returned %d\n", rv);
928 goto exit;
929 }
930
931 dev_dbg(dev, "INDICATOR_PULSE returned %x\n", buffer[0]);
932
933 if (buffer[0] != USBTMC_STATUS_SUCCESS) {
934 dev_err(dev, "INDICATOR_PULSE returned %x\n", buffer[0]);
935 rv = -EPERM;
936 goto exit;
937 }
938 rv = 0;
939
940exit:
941 kfree(buffer);
942 return rv;
943}
944
945static long usbtmc_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
946{
947 struct usbtmc_device_data *data;
948 int retval = -EBADRQC;
949
950 data = file->private_data;
951 mutex_lock(&data->io_mutex);
86286883
ON		 952 if (data->zombie) {
953 retval = -ENODEV;
954 goto skip_io_on_zombie;
955 }
5b775f67
GKH		 956
957 switch (cmd) {
958 case USBTMC_IOCTL_CLEAR_OUT_HALT:
959 retval = usbtmc_ioctl_clear_out_halt(data);
a92b63e7 960 break;
5b775f67
GKH		 961
962 case USBTMC_IOCTL_CLEAR_IN_HALT:
963 retval = usbtmc_ioctl_clear_in_halt(data);
a92b63e7 964 break;
5b775f67
GKH		 965
966 case USBTMC_IOCTL_INDICATOR_PULSE:
967 retval = usbtmc_ioctl_indicator_pulse(data);
a92b63e7 968 break;
5b775f67
GKH		 969
970 case USBTMC_IOCTL_CLEAR:
971 retval = usbtmc_ioctl_clear(data);
a92b63e7 972 break;
5b775f67
GKH		 973
974 case USBTMC_IOCTL_ABORT_BULK_OUT:
975 retval = usbtmc_ioctl_abort_bulk_out(data);
a92b63e7 976 break;
5b775f67
GKH		 977
978 case USBTMC_IOCTL_ABORT_BULK_IN:
979 retval = usbtmc_ioctl_abort_bulk_in(data);
a92b63e7 980 break;
5b775f67
GKH		 981 }
982
86286883 983skip_io_on_zombie:
5b775f67
GKH		 984 mutex_unlock(&data->io_mutex);
985 return retval;
986}
987
988static struct file_operations fops = {
989 .owner = THIS_MODULE,
990 .read = usbtmc_read,
991 .write = usbtmc_write,
992 .open = usbtmc_open,
993 .release = usbtmc_release,
994 .unlocked_ioctl = usbtmc_ioctl,
995};
996
997static struct usb_class_driver usbtmc_class = {
998 .name = "usbtmc%d",
999 .fops = &fops,
1000 .minor_base = USBTMC_MINOR_BASE,
1001};
1002
1003
1004static int usbtmc_probe(struct usb_interface *intf,
1005 const struct usb_device_id *id)
1006{
1007 struct usbtmc_device_data *data;
1008 struct usb_host_interface *iface_desc;
1009 struct usb_endpoint_descriptor *endpoint;
1010 int n;
1011 int retcode;
1012
1013 dev_dbg(&intf->dev, "%s called\n", __func__);
1014
1015 data = kmalloc(sizeof(struct usbtmc_device_data), GFP_KERNEL);
1016 if (!data) {
1017 dev_err(&intf->dev, "Unable to allocate kernel memory\n");
1018 return -ENOMEM;
1019 }
1020
1021 data->intf = intf;
1022 data->id = id;
1023 data->usb_dev = usb_get_dev(interface_to_usbdev(intf));
1024 usb_set_intfdata(intf, data);
1025 kref_init(&data->kref);
1026 mutex_init(&data->io_mutex);
86286883 1027 data->zombie = 0;
5b775f67
GKH		 1028
1029 /* Initialize USBTMC bTag and other fields */
1030 data->bTag = 1;
1031 data->TermCharEnabled = 0;
1032 data->TermChar = '\n';
1033
1034 /* USBTMC devices have only one setting, so use that */
1035 iface_desc = data->intf->cur_altsetting;
1036
1037 /* Find bulk in endpoint */
1038 for (n = 0; n < iface_desc->desc.bNumEndpoints; n++) {
1039 endpoint = &iface_desc->endpoint[n].desc;
1040
1041 if (usb_endpoint_is_bulk_in(endpoint)) {
1042 data->bulk_in = endpoint->bEndpointAddress;
1043 dev_dbg(&intf->dev, "Found bulk in endpoint at %u\n",
1044 data->bulk_in);
1045 break;
1046 }
1047 }
1048
1049 /* Find bulk out endpoint */
1050 for (n = 0; n < iface_desc->desc.bNumEndpoints; n++) {
1051 endpoint = &iface_desc->endpoint[n].desc;
1052
1053 if (usb_endpoint_is_bulk_out(endpoint)) {
1054 data->bulk_out = endpoint->bEndpointAddress;
1055 dev_dbg(&intf->dev, "Found Bulk out endpoint at %u\n",
1056 data->bulk_out);
1057 break;
1058 }
1059 }
1060
1061 retcode = get_capabilities(data);
1062 if (retcode)
1063 dev_err(&intf->dev, "can't read capabilities\n");
1064 else
1065 retcode = sysfs_create_group(&intf->dev.kobj,
1066 &capability_attr_grp);
1067
1068 retcode = sysfs_create_group(&intf->dev.kobj, &data_attr_grp);
1069
1070 retcode = usb_register_dev(intf, &usbtmc_class);
1071 if (retcode) {
1072 dev_err(&intf->dev, "Not able to get a minor"
1073 " (base %u, slice default): %d\n", USBTMC_MINOR_BASE,
1074 retcode);
1075 goto error_register;
1076 }
1077 dev_dbg(&intf->dev, "Using minor number %d\n", intf->minor);
1078
1079 return 0;
1080
1081error_register:
1082 sysfs_remove_group(&intf->dev.kobj, &capability_attr_grp);
1083 sysfs_remove_group(&intf->dev.kobj, &data_attr_grp);
1084 kref_put(&data->kref, usbtmc_delete);
1085 return retcode;
1086}
1087
1088static void usbtmc_disconnect(struct usb_interface *intf)
1089{
1090 struct usbtmc_device_data *data;
1091
1092 dev_dbg(&intf->dev, "usbtmc_disconnect called\n");
1093
1094 data = usb_get_intfdata(intf);
1095 usb_deregister_dev(intf, &usbtmc_class);
1096 sysfs_remove_group(&intf->dev.kobj, &capability_attr_grp);
1097 sysfs_remove_group(&intf->dev.kobj, &data_attr_grp);
86286883
ON		 1098 mutex_lock(&data->io_mutex);
1099 data->zombie = 1;
1100 mutex_unlock(&data->io_mutex);
5b775f67
GKH		 1101 kref_put(&data->kref, usbtmc_delete);
1102}
1103
a4708103
ON		 1104static int usbtmc_suspend (struct usb_interface *intf, pm_message_t message)
1105{
1106 /* this driver does not have pending URBs */
1107 return 0;
1108}
1109
1110static int usbtmc_resume (struct usb_interface *intf)
1111{
1112 return 0;
1113}
1114
5b775f67
GKH		 1115static struct usb_driver usbtmc_driver = {
1116 .name = "usbtmc",
1117 .id_table = usbtmc_devices,
1118 .probe = usbtmc_probe,
a4708103
ON		 1119 .disconnect = usbtmc_disconnect,
1120 .suspend = usbtmc_suspend,
1121 .resume = usbtmc_resume,
5b775f67
GKH		 1122};
1123
1124static int __init usbtmc_init(void)
1125{
1126 int retcode;
1127
1128 retcode = usb_register(&usbtmc_driver);
1129 if (retcode)
1130 printk(KERN_ERR KBUILD_MODNAME": Unable to register driver\n");
1131 return retcode;
1132}
1133module_init(usbtmc_init);
1134
1135static void __exit usbtmc_exit(void)
1136{
1137 usb_deregister(&usbtmc_driver);
1138}
1139module_exit(usbtmc_exit);
1140
1141MODULE_LICENSE("GPL");
Linux 6.x block layer and io_uring tree(s)