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