drivers/usb/class/usbtmc.c

   1 /**
   2  * drivers/usb/class/usbtmc.c - USB Test & Measurement 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 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  23
  24 #include <linux/module.h>
  25 #include <linux/kernel.h>
  26 #include <linux/fs.h>
  27 #include <linux/uaccess.h>
  28 #include <linux/kref.h>
  29 #include <linux/slab.h>
  30 #include <linux/poll.h>
  31 #include <linux/mutex.h>
  32 #include <linux/usb.h>
  33 #include <linux/usb/tmc.h>
  34
  35
  36 #define RIGOL                   1
  37 #define USBTMC_HEADER_SIZE      12
  38 #define USBTMC_MINOR_BASE       176
  39
  40 /*
  41  * Size of driver internal IO buffer. Must be multiple of 4 and at least as
  42  * large as wMaxPacketSize (which is usually 512 bytes).
  43  */
  44 #define USBTMC_SIZE_IOBUFFER    2048
  45
  46 /* Default USB timeout (in milliseconds) */
  47 #define USBTMC_TIMEOUT          5000
  48
  49 /*
  50  * Maximum number of read cycles to empty bulk in endpoint during CLEAR and
  51  * ABORT_BULK_IN requests. Ends the loop if (for whatever reason) a short
  52  * packet is never read.
  53  */
  54 #define USBTMC_MAX_READS_TO_CLEAR_BULK_IN       100
  55
  56 static const struct usb_device_id usbtmc_devices[] = {
  57         { USB_INTERFACE_INFO(USB_CLASS_APP_SPEC, 3, 0), },
  58         { USB_INTERFACE_INFO(USB_CLASS_APP_SPEC, 3, 1), },
  59         { 0, } /* terminating entry */
  60 };
  61 MODULE_DEVICE_TABLE(usb, usbtmc_devices);
  62
  63 /*
  64  * This structure is the capabilities for the device
  65  * See section 4.2.1.8 of the USBTMC specification,
  66  * and section 4.2.2 of the USBTMC usb488 subclass
  67  * specification for details.
  68  */
  69 struct usbtmc_dev_capabilities {
  70         __u8 interface_capabilities;
  71         __u8 device_capabilities;
  72         __u8 usb488_interface_capabilities;
  73         __u8 usb488_device_capabilities;
  74 };
  75
  76 /* This structure holds private data for each USBTMC device. One copy is
  77  * allocated for each USBTMC device in the driver's probe function.
  78  */
  79 struct usbtmc_device_data {
  80         const struct usb_device_id *id;
  81         struct usb_device *usb_dev;
  82         struct usb_interface *intf;
  83
  84         unsigned int bulk_in;
  85         unsigned int bulk_out;
  86
  87         u8 bTag;
  88         u8 bTag_last_write;     /* needed for abort */
  89         u8 bTag_last_read;      /* needed for abort */
  90
  91         /* data for interrupt in endpoint handling */
  92         u8             bNotify1;
  93         u8             bNotify2;
  94         u16            ifnum;
  95         u8             iin_bTag;
  96         u8            *iin_buffer;
  97         atomic_t       iin_data_valid;
  98         unsigned int   iin_ep;
  99         int            iin_ep_present;
 100         int            iin_interval;
 101         struct urb    *iin_urb;
 102         u16            iin_wMaxPacketSize;
 103         atomic_t       srq_asserted;
 104
 105         /* coalesced usb488_caps from usbtmc_dev_capabilities */
 106         __u8 usb488_caps;
 107
 108         u8 rigol_quirk;
 109
 110         /* attributes from the USB TMC spec for this device */
 111         u8 TermChar;
 112         bool TermCharEnabled;
 113         bool auto_abort;
 114
 115         bool zombie; /* fd of disconnected device */
 116
 117         struct usbtmc_dev_capabilities  capabilities;
 118         struct kref kref;
 119         struct mutex io_mutex;  /* only one i/o function running at a time */
 120         wait_queue_head_t waitq;
 121         struct fasync_struct *fasync;
 122 };
 123 #define to_usbtmc_data(d) container_of(d, struct usbtmc_device_data, kref)
 124
 125 struct usbtmc_ID_rigol_quirk {
 126         __u16 idVendor;
 127         __u16 idProduct;
 128 };
 129
 130 static const struct usbtmc_ID_rigol_quirk usbtmc_id_quirk[] = {
 131         { 0x1ab1, 0x0588 },
 132         { 0x1ab1, 0x04b0 },
 133         { 0, 0 }
 134 };
 135
 136 /* Forward declarations */
 137 static struct usb_driver usbtmc_driver;
 138
 139 static void usbtmc_delete(struct kref *kref)
 140 {
 141         struct usbtmc_device_data *data = to_usbtmc_data(kref);
 142
 143         usb_put_dev(data->usb_dev);
 144         kfree(data);
 145 }
 146
 147 static int usbtmc_open(struct inode *inode, struct file *filp)
 148 {
 149         struct usb_interface *intf;
 150         struct usbtmc_device_data *data;
 151         int retval = 0;
 152
 153         intf = usb_find_interface(&usbtmc_driver, iminor(inode));
 154         if (!intf) {
 155                 pr_err("can not find device for minor %d", iminor(inode));
 156                 return -ENODEV;
 157         }
 158
 159         data = usb_get_intfdata(intf);
 160         /* Protect reference to data from file structure until release */
 161         kref_get(&data->kref);
 162
 163         /* Store pointer in file structure's private data field */
 164         filp->private_data = data;
 165
 166         return retval;
 167 }
 168
 169 static int usbtmc_release(struct inode *inode, struct file *file)
 170 {
 171         struct usbtmc_device_data *data = file->private_data;
 172
 173         kref_put(&data->kref, usbtmc_delete);
 174         return 0;
 175 }
 176
 177 static int usbtmc_ioctl_abort_bulk_in(struct usbtmc_device_data *data)
 178 {
 179         u8 *buffer;
 180         struct device *dev;
 181         int rv;
 182         int n;
 183         int actual;
 184         struct usb_host_interface *current_setting;
 185         int max_size;
 186
 187         dev = &data->intf->dev;
 188         buffer = kmalloc(USBTMC_SIZE_IOBUFFER, GFP_KERNEL);
 189         if (!buffer)
 190                 return -ENOMEM;
 191
 192         rv = usb_control_msg(data->usb_dev,
 193                              usb_rcvctrlpipe(data->usb_dev, 0),
 194                              USBTMC_REQUEST_INITIATE_ABORT_BULK_IN,
 195                              USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_ENDPOINT,
 196                              data->bTag_last_read, data->bulk_in,
 197                              buffer, 2, USBTMC_TIMEOUT);
 198
 199         if (rv < 0) {
 200                 dev_err(dev, "usb_control_msg returned %d\n", rv);
 201                 goto exit;
 202         }
 203
 204         dev_dbg(dev, "INITIATE_ABORT_BULK_IN returned %x\n", buffer[0]);
 205
 206         if (buffer[0] == USBTMC_STATUS_FAILED) {
 207                 rv = 0;
 208                 goto exit;
 209         }
 210
 211         if (buffer[0] != USBTMC_STATUS_SUCCESS) {
 212                 dev_err(dev, "INITIATE_ABORT_BULK_IN returned %x\n",
 213                         buffer[0]);
 214                 rv = -EPERM;
 215                 goto exit;
 216         }
 217
 218         max_size = 0;
 219         current_setting = data->intf->cur_altsetting;
 220         for (n = 0; n < current_setting->desc.bNumEndpoints; n++)
 221                 if (current_setting->endpoint[n].desc.bEndpointAddress ==
 222                         data->bulk_in)
 223                         max_size = usb_endpoint_maxp(&current_setting->endpoint[n].desc);
 224
 225         if (max_size == 0) {
 226                 dev_err(dev, "Couldn't get wMaxPacketSize\n");
 227                 rv = -EPERM;
 228                 goto exit;
 229         }
 230
 231         dev_dbg(&data->intf->dev, "wMaxPacketSize is %d\n", max_size);
 232
 233         n = 0;
 234
 235         do {
 236                 dev_dbg(dev, "Reading from bulk in EP\n");
 237
 238                 rv = usb_bulk_msg(data->usb_dev,
 239                                   usb_rcvbulkpipe(data->usb_dev,
 240                                                   data->bulk_in),
 241                                   buffer, USBTMC_SIZE_IOBUFFER,
 242                                   &actual, USBTMC_TIMEOUT);
 243
 244                 n++;
 245
 246                 if (rv < 0) {
 247                         dev_err(dev, "usb_bulk_msg returned %d\n", rv);
 248                         goto exit;
 249                 }
 250         } while ((actual == max_size) &&
 251                  (n < USBTMC_MAX_READS_TO_CLEAR_BULK_IN));
 252
 253         if (actual == max_size) {
 254                 dev_err(dev, "Couldn't clear device buffer within %d cycles\n",
 255                         USBTMC_MAX_READS_TO_CLEAR_BULK_IN);
 256                 rv = -EPERM;
 257                 goto exit;
 258         }
 259
 260         n = 0;
 261
 262 usbtmc_abort_bulk_in_status:
 263         rv = usb_control_msg(data->usb_dev,
 264                              usb_rcvctrlpipe(data->usb_dev, 0),
 265                              USBTMC_REQUEST_CHECK_ABORT_BULK_IN_STATUS,
 266                              USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_ENDPOINT,
 267                              0, data->bulk_in, buffer, 0x08,
 268                              USBTMC_TIMEOUT);
 269
 270         if (rv < 0) {
 271                 dev_err(dev, "usb_control_msg returned %d\n", rv);
 272                 goto exit;
 273         }
 274
 275         dev_dbg(dev, "INITIATE_ABORT_BULK_IN returned %x\n", buffer[0]);
 276
 277         if (buffer[0] == USBTMC_STATUS_SUCCESS) {
 278                 rv = 0;
 279                 goto exit;
 280         }
 281
 282         if (buffer[0] != USBTMC_STATUS_PENDING) {
 283                 dev_err(dev, "INITIATE_ABORT_BULK_IN returned %x\n", buffer[0]);
 284                 rv = -EPERM;
 285                 goto exit;
 286         }
 287
 288         if (buffer[1] == 1)
 289                 do {
 290                         dev_dbg(dev, "Reading from bulk in EP\n");
 291
 292                         rv = usb_bulk_msg(data->usb_dev,
 293                                           usb_rcvbulkpipe(data->usb_dev,
 294                                                           data->bulk_in),
 295                                           buffer, USBTMC_SIZE_IOBUFFER,
 296                                           &actual, USBTMC_TIMEOUT);
 297
 298                         n++;
 299
 300                         if (rv < 0) {
 301                                 dev_err(dev, "usb_bulk_msg returned %d\n", rv);
 302                                 goto exit;
 303                         }
 304                 } while ((actual == max_size) &&
 305                          (n < USBTMC_MAX_READS_TO_CLEAR_BULK_IN));
 306
 307         if (actual == max_size) {
 308                 dev_err(dev, "Couldn't clear device buffer within %d cycles\n",
 309                         USBTMC_MAX_READS_TO_CLEAR_BULK_IN);
 310                 rv = -EPERM;
 311                 goto exit;
 312         }
 313
 314         goto usbtmc_abort_bulk_in_status;
 315
 316 exit:
 317         kfree(buffer);
 318         return rv;
 319
 320 }
 321
 322 static int usbtmc_ioctl_abort_bulk_out(struct usbtmc_device_data *data)
 323 {
 324         struct device *dev;
 325         u8 *buffer;
 326         int rv;
 327         int n;
 328
 329         dev = &data->intf->dev;
 330
 331         buffer = kmalloc(8, GFP_KERNEL);
 332         if (!buffer)
 333                 return -ENOMEM;
 334
 335         rv = usb_control_msg(data->usb_dev,
 336                              usb_rcvctrlpipe(data->usb_dev, 0),
 337                              USBTMC_REQUEST_INITIATE_ABORT_BULK_OUT,
 338                              USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_ENDPOINT,
 339                              data->bTag_last_write, data->bulk_out,
 340                              buffer, 2, USBTMC_TIMEOUT);
 341
 342         if (rv < 0) {
 343                 dev_err(dev, "usb_control_msg returned %d\n", rv);
 344                 goto exit;
 345         }
 346
 347         dev_dbg(dev, "INITIATE_ABORT_BULK_OUT returned %x\n", buffer[0]);
 348
 349         if (buffer[0] != USBTMC_STATUS_SUCCESS) {
 350                 dev_err(dev, "INITIATE_ABORT_BULK_OUT returned %x\n",
 351                         buffer[0]);
 352                 rv = -EPERM;
 353                 goto exit;
 354         }
 355
 356         n = 0;
 357
 358 usbtmc_abort_bulk_out_check_status:
 359         rv = usb_control_msg(data->usb_dev,
 360                              usb_rcvctrlpipe(data->usb_dev, 0),
 361                              USBTMC_REQUEST_CHECK_ABORT_BULK_OUT_STATUS,
 362                              USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_ENDPOINT,
 363                              0, data->bulk_out, buffer, 0x08,
 364                              USBTMC_TIMEOUT);
 365         n++;
 366         if (rv < 0) {
 367                 dev_err(dev, "usb_control_msg returned %d\n", rv);
 368                 goto exit;
 369         }
 370
 371         dev_dbg(dev, "CHECK_ABORT_BULK_OUT returned %x\n", buffer[0]);
 372
 373         if (buffer[0] == USBTMC_STATUS_SUCCESS)
 374                 goto usbtmc_abort_bulk_out_clear_halt;
 375
 376         if ((buffer[0] == USBTMC_STATUS_PENDING) &&
 377             (n < USBTMC_MAX_READS_TO_CLEAR_BULK_IN))
 378                 goto usbtmc_abort_bulk_out_check_status;
 379
 380         rv = -EPERM;
 381         goto exit;
 382
 383 usbtmc_abort_bulk_out_clear_halt:
 384         rv = usb_clear_halt(data->usb_dev,
 385                             usb_sndbulkpipe(data->usb_dev, data->bulk_out));
 386
 387         if (rv < 0) {
 388                 dev_err(dev, "usb_control_msg returned %d\n", rv);
 389                 goto exit;
 390         }
 391         rv = 0;
 392
 393 exit:
 394         kfree(buffer);
 395         return rv;
 396 }
 397
 398 static int usbtmc488_ioctl_read_stb(struct usbtmc_device_data *data,
 399                                 void __user *arg)
 400 {
 401         struct device *dev = &data->intf->dev;
 402         u8 *buffer;
 403         u8 tag;
 404         __u8 stb;
 405         int rv;
 406
 407         dev_dbg(dev, "Enter ioctl_read_stb iin_ep_present: %d\n",
 408                 data->iin_ep_present);
 409
 410         buffer = kmalloc(8, GFP_KERNEL);
 411         if (!buffer)
 412                 return -ENOMEM;
 413
 414         atomic_set(&data->iin_data_valid, 0);
 415
 416         /* must issue read_stb before using poll or select */
 417         atomic_set(&data->srq_asserted, 0);
 418
 419         rv = usb_control_msg(data->usb_dev,
 420                         usb_rcvctrlpipe(data->usb_dev, 0),
 421                         USBTMC488_REQUEST_READ_STATUS_BYTE,
 422                         USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE,
 423                         data->iin_bTag,
 424                         data->ifnum,
 425                         buffer, 0x03, USBTMC_TIMEOUT);
 426         if (rv < 0) {
 427                 dev_err(dev, "stb usb_control_msg returned %d\n", rv);
 428                 goto exit;
 429         }
 430
 431         if (buffer[0] != USBTMC_STATUS_SUCCESS) {
 432                 dev_err(dev, "control status returned %x\n", buffer[0]);
 433                 rv = -EIO;
 434                 goto exit;
 435         }
 436
 437         if (data->iin_ep_present) {
 438                 rv = wait_event_interruptible_timeout(
 439                         data->waitq,
 440                         atomic_read(&data->iin_data_valid) != 0,
 441                         USBTMC_TIMEOUT);
 442                 if (rv < 0) {
 443                         dev_dbg(dev, "wait interrupted %d\n", rv);
 444                         goto exit;
 445                 }
 446
 447                 if (rv == 0) {
 448                         dev_dbg(dev, "wait timed out\n");
 449                         rv = -ETIME;
 450                         goto exit;
 451                 }
 452
 453                 tag = data->bNotify1 & 0x7f;
 454                 if (tag != data->iin_bTag) {
 455                         dev_err(dev, "expected bTag %x got %x\n",
 456                                 data->iin_bTag, tag);
 457                 }
 458
 459                 stb = data->bNotify2;
 460         } else {
 461                 stb = buffer[2];
 462         }
 463
 464         rv = copy_to_user(arg, &stb, sizeof(stb));
 465         if (rv)
 466                 rv = -EFAULT;
 467
 468  exit:
 469         /* bump interrupt bTag */
 470         data->iin_bTag += 1;
 471         if (data->iin_bTag > 127)
 472                 /* 1 is for SRQ see USBTMC-USB488 subclass spec section 4.3.1 */
 473                 data->iin_bTag = 2;
 474
 475         kfree(buffer);
 476         return rv;
 477 }
 478
 479 static int usbtmc488_ioctl_simple(struct usbtmc_device_data *data,
 480                                 void __user *arg, unsigned int cmd)
 481 {
 482         struct device *dev = &data->intf->dev;
 483         __u8 val;
 484         u8 *buffer;
 485         u16 wValue;
 486         int rv;
 487
 488         if (!(data->usb488_caps & USBTMC488_CAPABILITY_SIMPLE))
 489                 return -EINVAL;
 490
 491         buffer = kmalloc(8, GFP_KERNEL);
 492         if (!buffer)
 493                 return -ENOMEM;
 494
 495         if (cmd == USBTMC488_REQUEST_REN_CONTROL) {
 496                 rv = copy_from_user(&val, arg, sizeof(val));
 497                 if (rv) {
 498                         rv = -EFAULT;
 499                         goto exit;
 500                 }
 501                 wValue = val ? 1 : 0;
 502         } else {
 503                 wValue = 0;
 504         }
 505
 506         rv = usb_control_msg(data->usb_dev,
 507                         usb_rcvctrlpipe(data->usb_dev, 0),
 508                         cmd,
 509                         USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE,
 510                         wValue,
 511                         data->ifnum,
 512                         buffer, 0x01, USBTMC_TIMEOUT);
 513         if (rv < 0) {
 514                 dev_err(dev, "simple usb_control_msg failed %d\n", rv);
 515                 goto exit;
 516         } else if (rv != 1) {
 517                 dev_warn(dev, "simple usb_control_msg returned %d\n", rv);
 518                 rv = -EIO;
 519                 goto exit;
 520         }
 521
 522         if (buffer[0] != USBTMC_STATUS_SUCCESS) {
 523                 dev_err(dev, "simple control status returned %x\n", buffer[0]);
 524                 rv = -EIO;
 525                 goto exit;
 526         }
 527         rv = 0;
 528
 529  exit:
 530         kfree(buffer);
 531         return rv;
 532 }
 533
 534 /*
 535  * Sends a REQUEST_DEV_DEP_MSG_IN message on the Bulk-OUT endpoint.
 536  * @transfer_size: number of bytes to request from the device.
 537  *
 538  * See the USBTMC specification, Table 4.
 539  *
 540  * Also updates bTag_last_write.
 541  */
 542 static int send_request_dev_dep_msg_in(struct usbtmc_device_data *data, size_t transfer_size)
 543 {
 544         int retval;
 545         u8 *buffer;
 546         int actual;
 547
 548         buffer = kmalloc(USBTMC_HEADER_SIZE, GFP_KERNEL);
 549         if (!buffer)
 550                 return -ENOMEM;
 551         /* Setup IO buffer for REQUEST_DEV_DEP_MSG_IN message
 552          * Refer to class specs for details
 553          */
 554         buffer[0] = 2;
 555         buffer[1] = data->bTag;
 556         buffer[2] = ~data->bTag;
 557         buffer[3] = 0; /* Reserved */
 558         buffer[4] = transfer_size >> 0;
 559         buffer[5] = transfer_size >> 8;
 560         buffer[6] = transfer_size >> 16;
 561         buffer[7] = transfer_size >> 24;
 562         buffer[8] = data->TermCharEnabled * 2;
 563         /* Use term character? */
 564         buffer[9] = data->TermChar;
 565         buffer[10] = 0; /* Reserved */
 566         buffer[11] = 0; /* Reserved */
 567
 568         /* Send bulk URB */
 569         retval = usb_bulk_msg(data->usb_dev,
 570                               usb_sndbulkpipe(data->usb_dev,
 571                                               data->bulk_out),
 572                               buffer, USBTMC_HEADER_SIZE, &actual, USBTMC_TIMEOUT);
 573
 574         /* Store bTag (in case we need to abort) */
 575         data->bTag_last_write = data->bTag;
 576
 577         /* Increment bTag -- and increment again if zero */
 578         data->bTag++;
 579         if (!data->bTag)
 580                 data->bTag++;
 581
 582         kfree(buffer);
 583         if (retval < 0) {
 584                 dev_err(&data->intf->dev, "usb_bulk_msg in send_request_dev_dep_msg_in() returned %d\n", retval);
 585                 return retval;
 586         }
 587
 588         return 0;
 589 }
 590
 591 static ssize_t usbtmc_read(struct file *filp, char __user *buf,
 592                            size_t count, loff_t *f_pos)
 593 {
 594         struct usbtmc_device_data *data;
 595         struct device *dev;
 596         u32 n_characters;
 597         u8 *buffer;
 598         int actual;
 599         size_t done;
 600         size_t remaining;
 601         int retval;
 602         size_t this_part;
 603
 604         /* Get pointer to private data structure */
 605         data = filp->private_data;
 606         dev = &data->intf->dev;
 607
 608         buffer = kmalloc(USBTMC_SIZE_IOBUFFER, GFP_KERNEL);
 609         if (!buffer)
 610                 return -ENOMEM;
 611
 612         mutex_lock(&data->io_mutex);
 613         if (data->zombie) {
 614                 retval = -ENODEV;
 615                 goto exit;
 616         }
 617
 618         if (data->rigol_quirk) {
 619                 dev_dbg(dev, "usb_bulk_msg_in: count(%zu)\n", count);
 620
 621                 retval = send_request_dev_dep_msg_in(data, count);
 622
 623                 if (retval < 0) {
 624                         if (data->auto_abort)
 625                                 usbtmc_ioctl_abort_bulk_out(data);
 626                         goto exit;
 627                 }
 628         }
 629
 630         /* Loop until we have fetched everything we requested */
 631         remaining = count;
 632         this_part = remaining;
 633         done = 0;
 634
 635         while (remaining > 0) {
 636                 if (!data->rigol_quirk) {
 637                         dev_dbg(dev, "usb_bulk_msg_in: remaining(%zu), count(%zu)\n", remaining, count);
 638
 639                         if (remaining > USBTMC_SIZE_IOBUFFER - USBTMC_HEADER_SIZE - 3)
 640                                 this_part = USBTMC_SIZE_IOBUFFER - USBTMC_HEADER_SIZE - 3;
 641                         else
 642                                 this_part = remaining;
 643
 644                         retval = send_request_dev_dep_msg_in(data, this_part);
 645                         if (retval < 0) {
 646                         dev_err(dev, "usb_bulk_msg returned %d\n", retval);
 647                                 if (data->auto_abort)
 648                                         usbtmc_ioctl_abort_bulk_out(data);
 649                                 goto exit;
 650                         }
 651                 }
 652
 653                 /* Send bulk URB */
 654                 retval = usb_bulk_msg(data->usb_dev,
 655                                       usb_rcvbulkpipe(data->usb_dev,
 656                                                       data->bulk_in),
 657                                       buffer, USBTMC_SIZE_IOBUFFER, &actual,
 658                                       USBTMC_TIMEOUT);
 659
 660                 dev_dbg(dev, "usb_bulk_msg: retval(%u), done(%zu), remaining(%zu), actual(%d)\n", retval, done, remaining, actual);
 661
 662                 /* Store bTag (in case we need to abort) */
 663                 data->bTag_last_read = data->bTag;
 664
 665                 if (retval < 0) {
 666                         dev_dbg(dev, "Unable to read data, error %d\n", retval);
 667                         if (data->auto_abort)
 668                                 usbtmc_ioctl_abort_bulk_in(data);
 669                         goto exit;
 670                 }
 671
 672                 /* Parse header in first packet */
 673                 if ((done == 0) || !data->rigol_quirk) {
 674                         /* Sanity checks for the header */
 675                         if (actual < USBTMC_HEADER_SIZE) {
 676                                 dev_err(dev, "Device sent too small first packet: %u < %u\n", actual, USBTMC_HEADER_SIZE);
 677                                 if (data->auto_abort)
 678                                         usbtmc_ioctl_abort_bulk_in(data);
 679                                 goto exit;
 680                         }
 681
 682                         if (buffer[0] != 2) {
 683                                 dev_err(dev, "Device sent reply with wrong MsgID: %u != 2\n", buffer[0]);
 684                                 if (data->auto_abort)
 685                                         usbtmc_ioctl_abort_bulk_in(data);
 686                                 goto exit;
 687                         }
 688
 689                         if (buffer[1] != data->bTag_last_write) {
 690                                 dev_err(dev, "Device sent reply with wrong bTag: %u != %u\n", buffer[1], data->bTag_last_write);
 691                                 if (data->auto_abort)
 692                                         usbtmc_ioctl_abort_bulk_in(data);
 693                                 goto exit;
 694                         }
 695
 696                         /* How many characters did the instrument send? */
 697                         n_characters = buffer[4] +
 698                                        (buffer[5] << 8) +
 699                                        (buffer[6] << 16) +
 700                                        (buffer[7] << 24);
 701
 702                         if (n_characters > this_part) {
 703                                 dev_err(dev, "Device wants to return more data than requested: %u > %zu\n", n_characters, count);
 704                                 if (data->auto_abort)
 705                                         usbtmc_ioctl_abort_bulk_in(data);
 706                                 goto exit;
 707                         }
 708
 709                         /* Remove the USBTMC header */
 710                         actual -= USBTMC_HEADER_SIZE;
 711
 712                         /* Check if the message is smaller than requested */
 713                         if (data->rigol_quirk) {
 714                                 if (remaining > n_characters)
 715                                         remaining = n_characters;
 716                                 /* Remove padding if it exists */
 717                                 if (actual > remaining)
 718                                         actual = remaining;
 719                         }
 720                         else {
 721                                 if (this_part > n_characters)
 722                                         this_part = n_characters;
 723                                 /* Remove padding if it exists */
 724                                 if (actual > this_part)
 725                                         actual = this_part;
 726                         }
 727
 728                         dev_dbg(dev, "Bulk-IN header: N_characters(%u), bTransAttr(%u)\n", n_characters, buffer[8]);
 729
 730                         remaining -= actual;
 731
 732                         /* Terminate if end-of-message bit received from device */
 733                         if ((buffer[8] & 0x01) && (actual >= n_characters))
 734                                 remaining = 0;
 735
 736                         dev_dbg(dev, "Bulk-IN header: remaining(%zu), buf(%p), buffer(%p) done(%zu)\n", remaining,buf,buffer,done);
 737
 738
 739                         /* Copy buffer to user space */
 740                         if (copy_to_user(buf + done, &buffer[USBTMC_HEADER_SIZE], actual)) {
 741                                 /* There must have been an addressing problem */
 742                                 retval = -EFAULT;
 743                                 goto exit;
 744                         }
 745                         done += actual;
 746                 }
 747                 else  {
 748                         if (actual > remaining)
 749                                 actual = remaining;
 750
 751                         remaining -= actual;
 752
 753                         dev_dbg(dev, "Bulk-IN header cont: actual(%u), done(%zu), remaining(%zu), buf(%p), buffer(%p)\n", actual, done, remaining,buf,buffer);
 754
 755                         /* Copy buffer to user space */
 756                         if (copy_to_user(buf + done, buffer, actual)) {
 757                                 /* There must have been an addressing problem */
 758                                 retval = -EFAULT;
 759                                 goto exit;
 760                         }
 761                         done += actual;
 762                 }
 763         }
 764
 765         /* Update file position value */
 766         *f_pos = *f_pos + done;
 767         retval = done;
 768
 769 exit:
 770         mutex_unlock(&data->io_mutex);
 771         kfree(buffer);
 772         return retval;
 773 }
 774
 775 static ssize_t usbtmc_write(struct file *filp, const char __user *buf,
 776                             size_t count, loff_t *f_pos)
 777 {
 778         struct usbtmc_device_data *data;
 779         u8 *buffer;
 780         int retval;
 781         int actual;
 782         unsigned long int n_bytes;
 783         int remaining;
 784         int done;
 785         int this_part;
 786
 787         data = filp->private_data;
 788
 789         buffer = kmalloc(USBTMC_SIZE_IOBUFFER, GFP_KERNEL);
 790         if (!buffer)
 791                 return -ENOMEM;
 792
 793         mutex_lock(&data->io_mutex);
 794         if (data->zombie) {
 795                 retval = -ENODEV;
 796                 goto exit;
 797         }
 798
 799         remaining = count;
 800         done = 0;
 801
 802         while (remaining > 0) {
 803                 if (remaining > USBTMC_SIZE_IOBUFFER - USBTMC_HEADER_SIZE) {
 804                         this_part = USBTMC_SIZE_IOBUFFER - USBTMC_HEADER_SIZE;
 805                         buffer[8] = 0;
 806                 } else {
 807                         this_part = remaining;
 808                         buffer[8] = 1;
 809                 }
 810
 811                 /* Setup IO buffer for DEV_DEP_MSG_OUT message */
 812                 buffer[0] = 1;
 813                 buffer[1] = data->bTag;
 814                 buffer[2] = ~data->bTag;
 815                 buffer[3] = 0; /* Reserved */
 816                 buffer[4] = this_part >> 0;
 817                 buffer[5] = this_part >> 8;
 818                 buffer[6] = this_part >> 16;
 819                 buffer[7] = this_part >> 24;
 820                 /* buffer[8] is set above... */
 821                 buffer[9] = 0; /* Reserved */
 822                 buffer[10] = 0; /* Reserved */
 823                 buffer[11] = 0; /* Reserved */
 824
 825                 if (copy_from_user(&buffer[USBTMC_HEADER_SIZE], buf + done, this_part)) {
 826                         retval = -EFAULT;
 827                         goto exit;
 828                 }
 829
 830                 n_bytes = roundup(USBTMC_HEADER_SIZE + this_part, 4);
 831                 memset(buffer + USBTMC_HEADER_SIZE + this_part, 0, n_bytes - (USBTMC_HEADER_SIZE + this_part));
 832
 833                 do {
 834                         retval = usb_bulk_msg(data->usb_dev,
 835                                               usb_sndbulkpipe(data->usb_dev,
 836                                                               data->bulk_out),
 837                                               buffer, n_bytes,
 838                                               &actual, USBTMC_TIMEOUT);
 839                         if (retval != 0)
 840                                 break;
 841                         n_bytes -= actual;
 842                 } while (n_bytes);
 843
 844                 data->bTag_last_write = data->bTag;
 845                 data->bTag++;
 846
 847                 if (!data->bTag)
 848                         data->bTag++;
 849
 850                 if (retval < 0) {
 851                         dev_err(&data->intf->dev,
 852                                 "Unable to send data, error %d\n", retval);
 853                         if (data->auto_abort)
 854                                 usbtmc_ioctl_abort_bulk_out(data);
 855                         goto exit;
 856                 }
 857
 858                 remaining -= this_part;
 859                 done += this_part;
 860         }
 861
 862         retval = count;
 863 exit:
 864         mutex_unlock(&data->io_mutex);
 865         kfree(buffer);
 866         return retval;
 867 }
 868
 869 static int usbtmc_ioctl_clear(struct usbtmc_device_data *data)
 870 {
 871         struct usb_host_interface *current_setting;
 872         struct usb_endpoint_descriptor *desc;
 873         struct device *dev;
 874         u8 *buffer;
 875         int rv;
 876         int n;
 877         int actual = 0;
 878         int max_size;
 879
 880         dev = &data->intf->dev;
 881
 882         dev_dbg(dev, "Sending INITIATE_CLEAR request\n");
 883
 884         buffer = kmalloc(USBTMC_SIZE_IOBUFFER, GFP_KERNEL);
 885         if (!buffer)
 886                 return -ENOMEM;
 887
 888         rv = usb_control_msg(data->usb_dev,
 889                              usb_rcvctrlpipe(data->usb_dev, 0),
 890                              USBTMC_REQUEST_INITIATE_CLEAR,
 891                              USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE,
 892                              0, 0, buffer, 1, USBTMC_TIMEOUT);
 893         if (rv < 0) {
 894                 dev_err(dev, "usb_control_msg returned %d\n", rv);
 895                 goto exit;
 896         }
 897
 898         dev_dbg(dev, "INITIATE_CLEAR returned %x\n", buffer[0]);
 899
 900         if (buffer[0] != USBTMC_STATUS_SUCCESS) {
 901                 dev_err(dev, "INITIATE_CLEAR returned %x\n", buffer[0]);
 902                 rv = -EPERM;
 903                 goto exit;
 904         }
 905
 906         max_size = 0;
 907         current_setting = data->intf->cur_altsetting;
 908         for (n = 0; n < current_setting->desc.bNumEndpoints; n++) {
 909                 desc = &current_setting->endpoint[n].desc;
 910                 if (desc->bEndpointAddress == data->bulk_in)
 911                         max_size = usb_endpoint_maxp(desc);
 912         }
 913
 914         if (max_size == 0) {
 915                 dev_err(dev, "Couldn't get wMaxPacketSize\n");
 916                 rv = -EPERM;
 917                 goto exit;
 918         }
 919
 920         dev_dbg(dev, "wMaxPacketSize is %d\n", max_size);
 921
 922         n = 0;
 923
 924 usbtmc_clear_check_status:
 925
 926         dev_dbg(dev, "Sending CHECK_CLEAR_STATUS request\n");
 927
 928         rv = usb_control_msg(data->usb_dev,
 929                              usb_rcvctrlpipe(data->usb_dev, 0),
 930                              USBTMC_REQUEST_CHECK_CLEAR_STATUS,
 931                              USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE,
 932                              0, 0, buffer, 2, USBTMC_TIMEOUT);
 933         if (rv < 0) {
 934                 dev_err(dev, "usb_control_msg returned %d\n", rv);
 935                 goto exit;
 936         }
 937
 938         dev_dbg(dev, "CHECK_CLEAR_STATUS returned %x\n", buffer[0]);
 939
 940         if (buffer[0] == USBTMC_STATUS_SUCCESS)
 941                 goto usbtmc_clear_bulk_out_halt;
 942
 943         if (buffer[0] != USBTMC_STATUS_PENDING) {
 944                 dev_err(dev, "CHECK_CLEAR_STATUS returned %x\n", buffer[0]);
 945                 rv = -EPERM;
 946                 goto exit;
 947         }
 948
 949         if (buffer[1] == 1)
 950                 do {
 951                         dev_dbg(dev, "Reading from bulk in EP\n");
 952
 953                         rv = usb_bulk_msg(data->usb_dev,
 954                                           usb_rcvbulkpipe(data->usb_dev,
 955                                                           data->bulk_in),
 956                                           buffer, USBTMC_SIZE_IOBUFFER,
 957                                           &actual, USBTMC_TIMEOUT);
 958                         n++;
 959
 960                         if (rv < 0) {
 961                                 dev_err(dev, "usb_control_msg returned %d\n",
 962                                         rv);
 963                                 goto exit;
 964                         }
 965                 } while ((actual == max_size) &&
 966                           (n < USBTMC_MAX_READS_TO_CLEAR_BULK_IN));
 967
 968         if (actual == max_size) {
 969                 dev_err(dev, "Couldn't clear device buffer within %d cycles\n",
 970                         USBTMC_MAX_READS_TO_CLEAR_BULK_IN);
 971                 rv = -EPERM;
 972                 goto exit;
 973         }
 974
 975         goto usbtmc_clear_check_status;
 976
 977 usbtmc_clear_bulk_out_halt:
 978
 979         rv = usb_clear_halt(data->usb_dev,
 980                             usb_sndbulkpipe(data->usb_dev, data->bulk_out));
 981         if (rv < 0) {
 982                 dev_err(dev, "usb_control_msg returned %d\n", rv);
 983                 goto exit;
 984         }
 985         rv = 0;
 986
 987 exit:
 988         kfree(buffer);
 989         return rv;
 990 }
 991
 992 static int usbtmc_ioctl_clear_out_halt(struct usbtmc_device_data *data)
 993 {
 994         int rv;
 995
 996         rv = usb_clear_halt(data->usb_dev,
 997                             usb_sndbulkpipe(data->usb_dev, data->bulk_out));
 998
 999         if (rv < 0) {
1000                 dev_err(&data->usb_dev->dev, "usb_control_msg returned %d\n",
1001                         rv);
1002                 return rv;
1003         }
1004         return 0;
1005 }
1006
1007 static int usbtmc_ioctl_clear_in_halt(struct usbtmc_device_data *data)
1008 {
1009         int rv;
1010
1011         rv = usb_clear_halt(data->usb_dev,
1012                             usb_rcvbulkpipe(data->usb_dev, data->bulk_in));
1013
1014         if (rv < 0) {
1015                 dev_err(&data->usb_dev->dev, "usb_control_msg returned %d\n",
1016                         rv);
1017                 return rv;
1018         }
1019         return 0;
1020 }
1021
1022 static int get_capabilities(struct usbtmc_device_data *data)
1023 {
1024         struct device *dev = &data->usb_dev->dev;
1025         char *buffer;
1026         int rv = 0;
1027
1028         buffer = kmalloc(0x18, GFP_KERNEL);
1029         if (!buffer)
1030                 return -ENOMEM;
1031
1032         rv = usb_control_msg(data->usb_dev, usb_rcvctrlpipe(data->usb_dev, 0),
1033                              USBTMC_REQUEST_GET_CAPABILITIES,
1034                              USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE,
1035                              0, 0, buffer, 0x18, USBTMC_TIMEOUT);
1036         if (rv < 0) {
1037                 dev_err(dev, "usb_control_msg returned %d\n", rv);
1038                 goto err_out;
1039         }
1040
1041         dev_dbg(dev, "GET_CAPABILITIES returned %x\n", buffer[0]);
1042         if (buffer[0] != USBTMC_STATUS_SUCCESS) {
1043                 dev_err(dev, "GET_CAPABILITIES returned %x\n", buffer[0]);
1044                 rv = -EPERM;
1045                 goto err_out;
1046         }
1047         dev_dbg(dev, "Interface capabilities are %x\n", buffer[4]);
1048         dev_dbg(dev, "Device capabilities are %x\n", buffer[5]);
1049         dev_dbg(dev, "USB488 interface capabilities are %x\n", buffer[14]);
1050         dev_dbg(dev, "USB488 device capabilities are %x\n", buffer[15]);
1051
1052         data->capabilities.interface_capabilities = buffer[4];
1053         data->capabilities.device_capabilities = buffer[5];
1054         data->capabilities.usb488_interface_capabilities = buffer[14];
1055         data->capabilities.usb488_device_capabilities = buffer[15];
1056         data->usb488_caps = (buffer[14] & 0x07) | ((buffer[15] & 0x0f) << 4);
1057         rv = 0;
1058
1059 err_out:
1060         kfree(buffer);
1061         return rv;
1062 }
1063
1064 #define capability_attribute(name)                                      \
1065 static ssize_t name##_show(struct device *dev,                          \
1066                            struct device_attribute *attr, char *buf)    \
1067 {                                                                       \
1068         struct usb_interface *intf = to_usb_interface(dev);             \
1069         struct usbtmc_device_data *data = usb_get_intfdata(intf);       \
1070                                                                         \
1071         return sprintf(buf, "%d\n", data->capabilities.name);           \
1072 }                                                                       \
1073 static DEVICE_ATTR_RO(name)
1074
1075 capability_attribute(interface_capabilities);
1076 capability_attribute(device_capabilities);
1077 capability_attribute(usb488_interface_capabilities);
1078 capability_attribute(usb488_device_capabilities);
1079
1080 static struct attribute *capability_attrs[] = {
1081         &dev_attr_interface_capabilities.attr,
1082         &dev_attr_device_capabilities.attr,
1083         &dev_attr_usb488_interface_capabilities.attr,
1084         &dev_attr_usb488_device_capabilities.attr,
1085         NULL,
1086 };
1087
1088 static struct attribute_group capability_attr_grp = {
1089         .attrs = capability_attrs,
1090 };
1091
1092 static ssize_t TermChar_show(struct device *dev,
1093                              struct device_attribute *attr, char *buf)
1094 {
1095         struct usb_interface *intf = to_usb_interface(dev);
1096         struct usbtmc_device_data *data = usb_get_intfdata(intf);
1097
1098         return sprintf(buf, "%c\n", data->TermChar);
1099 }
1100
1101 static ssize_t TermChar_store(struct device *dev,
1102                               struct device_attribute *attr,
1103                               const char *buf, size_t count)
1104 {
1105         struct usb_interface *intf = to_usb_interface(dev);
1106         struct usbtmc_device_data *data = usb_get_intfdata(intf);
1107
1108         if (count < 1)
1109                 return -EINVAL;
1110         data->TermChar = buf[0];
1111         return count;
1112 }
1113 static DEVICE_ATTR_RW(TermChar);
1114
1115 #define data_attribute(name)                                            \
1116 static ssize_t name##_show(struct device *dev,                          \
1117                            struct device_attribute *attr, char *buf)    \
1118 {                                                                       \
1119         struct usb_interface *intf = to_usb_interface(dev);             \
1120         struct usbtmc_device_data *data = usb_get_intfdata(intf);       \
1121                                                                         \
1122         return sprintf(buf, "%d\n", data->name);                        \
1123 }                                                                       \
1124 static ssize_t name##_store(struct device *dev,                         \
1125                             struct device_attribute *attr,              \
1126                             const char *buf, size_t count)              \
1127 {                                                                       \
1128         struct usb_interface *intf = to_usb_interface(dev);             \
1129         struct usbtmc_device_data *data = usb_get_intfdata(intf);       \
1130         ssize_t result;                                                 \
1131         unsigned val;                                                   \
1132                                                                         \
1133         result = sscanf(buf, "%u\n", &val);                             \
1134         if (result != 1)                                                \
1135                 result = -EINVAL;                                       \
1136         data->name = val;                                               \
1137         if (result < 0)                                                 \
1138                 return result;                                          \
1139         else                                                            \
1140                 return count;                                           \
1141 }                                                                       \
1142 static DEVICE_ATTR_RW(name)
1143
1144 data_attribute(TermCharEnabled);
1145 data_attribute(auto_abort);
1146
1147 static struct attribute *data_attrs[] = {
1148         &dev_attr_TermChar.attr,
1149         &dev_attr_TermCharEnabled.attr,
1150         &dev_attr_auto_abort.attr,
1151         NULL,
1152 };
1153
1154 static struct attribute_group data_attr_grp = {
1155         .attrs = data_attrs,
1156 };
1157
1158 static int usbtmc_ioctl_indicator_pulse(struct usbtmc_device_data *data)
1159 {
1160         struct device *dev;
1161         u8 *buffer;
1162         int rv;
1163
1164         dev = &data->intf->dev;
1165
1166         buffer = kmalloc(2, GFP_KERNEL);
1167         if (!buffer)
1168                 return -ENOMEM;
1169
1170         rv = usb_control_msg(data->usb_dev,
1171                              usb_rcvctrlpipe(data->usb_dev, 0),
1172                              USBTMC_REQUEST_INDICATOR_PULSE,
1173                              USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE,
1174                              0, 0, buffer, 0x01, USBTMC_TIMEOUT);
1175
1176         if (rv < 0) {
1177                 dev_err(dev, "usb_control_msg returned %d\n", rv);
1178                 goto exit;
1179         }
1180
1181         dev_dbg(dev, "INDICATOR_PULSE returned %x\n", buffer[0]);
1182
1183         if (buffer[0] != USBTMC_STATUS_SUCCESS) {
1184                 dev_err(dev, "INDICATOR_PULSE returned %x\n", buffer[0]);
1185                 rv = -EPERM;
1186                 goto exit;
1187         }
1188         rv = 0;
1189
1190 exit:
1191         kfree(buffer);
1192         return rv;
1193 }
1194
1195 static long usbtmc_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
1196 {
1197         struct usbtmc_device_data *data;
1198         int retval = -EBADRQC;
1199
1200         data = file->private_data;
1201         mutex_lock(&data->io_mutex);
1202         if (data->zombie) {
1203                 retval = -ENODEV;
1204                 goto skip_io_on_zombie;
1205         }
1206
1207         switch (cmd) {
1208         case USBTMC_IOCTL_CLEAR_OUT_HALT:
1209                 retval = usbtmc_ioctl_clear_out_halt(data);
1210                 break;
1211
1212         case USBTMC_IOCTL_CLEAR_IN_HALT:
1213                 retval = usbtmc_ioctl_clear_in_halt(data);
1214                 break;
1215
1216         case USBTMC_IOCTL_INDICATOR_PULSE:
1217                 retval = usbtmc_ioctl_indicator_pulse(data);
1218                 break;
1219
1220         case USBTMC_IOCTL_CLEAR:
1221                 retval = usbtmc_ioctl_clear(data);
1222                 break;
1223
1224         case USBTMC_IOCTL_ABORT_BULK_OUT:
1225                 retval = usbtmc_ioctl_abort_bulk_out(data);
1226                 break;
1227
1228         case USBTMC_IOCTL_ABORT_BULK_IN:
1229                 retval = usbtmc_ioctl_abort_bulk_in(data);
1230                 break;
1231
1232         case USBTMC488_IOCTL_GET_CAPS:
1233                 retval = copy_to_user((void __user *)arg,
1234                                 &data->usb488_caps,
1235                                 sizeof(data->usb488_caps));
1236                 if (retval)
1237                         retval = -EFAULT;
1238                 break;
1239
1240         case USBTMC488_IOCTL_READ_STB:
1241                 retval = usbtmc488_ioctl_read_stb(data, (void __user *)arg);
1242                 break;
1243
1244         case USBTMC488_IOCTL_REN_CONTROL:
1245                 retval = usbtmc488_ioctl_simple(data, (void __user *)arg,
1246                                                 USBTMC488_REQUEST_REN_CONTROL);
1247                 break;
1248
1249         case USBTMC488_IOCTL_GOTO_LOCAL:
1250                 retval = usbtmc488_ioctl_simple(data, (void __user *)arg,
1251                                                 USBTMC488_REQUEST_GOTO_LOCAL);
1252                 break;
1253
1254         case USBTMC488_IOCTL_LOCAL_LOCKOUT:
1255                 retval = usbtmc488_ioctl_simple(data, (void __user *)arg,
1256                                                 USBTMC488_REQUEST_LOCAL_LOCKOUT);
1257                 break;
1258         }
1259
1260 skip_io_on_zombie:
1261         mutex_unlock(&data->io_mutex);
1262         return retval;
1263 }
1264
1265 static int usbtmc_fasync(int fd, struct file *file, int on)
1266 {
1267         struct usbtmc_device_data *data = file->private_data;
1268
1269         return fasync_helper(fd, file, on, &data->fasync);
1270 }
1271
1272 static unsigned int usbtmc_poll(struct file *file, poll_table *wait)
1273 {
1274         struct usbtmc_device_data *data = file->private_data;
1275         unsigned int mask;
1276
1277         mutex_lock(&data->io_mutex);
1278
1279         if (data->zombie) {
1280                 mask = POLLHUP | POLLERR;
1281                 goto no_poll;
1282         }
1283
1284         poll_wait(file, &data->waitq, wait);
1285
1286         mask = (atomic_read(&data->srq_asserted)) ? POLLIN | POLLRDNORM : 0;
1287
1288 no_poll:
1289         mutex_unlock(&data->io_mutex);
1290         return mask;
1291 }
1292
1293 static const struct file_operations fops = {
1294         .owner          = THIS_MODULE,
1295         .read           = usbtmc_read,
1296         .write          = usbtmc_write,
1297         .open           = usbtmc_open,
1298         .release        = usbtmc_release,
1299         .unlocked_ioctl = usbtmc_ioctl,
1300         .fasync         = usbtmc_fasync,
1301         .poll           = usbtmc_poll,
1302         .llseek         = default_llseek,
1303 };
1304
1305 static struct usb_class_driver usbtmc_class = {
1306         .name =         "usbtmc%d",
1307         .fops =         &fops,
1308         .minor_base =   USBTMC_MINOR_BASE,
1309 };
1310
1311 static void usbtmc_interrupt(struct urb *urb)
1312 {
1313         struct usbtmc_device_data *data = urb->context;
1314         struct device *dev = &data->intf->dev;
1315         int status = urb->status;
1316         int rv;
1317
1318         dev_dbg(&data->intf->dev, "int status: %d len %d\n",
1319                 status, urb->actual_length);
1320
1321         switch (status) {
1322         case 0: /* SUCCESS */
1323                 /* check for valid STB notification */
1324                 if (data->iin_buffer[0] > 0x81) {
1325                         data->bNotify1 = data->iin_buffer[0];
1326                         data->bNotify2 = data->iin_buffer[1];
1327                         atomic_set(&data->iin_data_valid, 1);
1328                         wake_up_interruptible(&data->waitq);
1329                         goto exit;
1330                 }
1331                 /* check for SRQ notification */
1332                 if (data->iin_buffer[0] == 0x81) {
1333                         if (data->fasync)
1334                                 kill_fasync(&data->fasync,
1335                                         SIGIO, POLL_IN);
1336
1337                         atomic_set(&data->srq_asserted, 1);
1338                         wake_up_interruptible(&data->waitq);
1339                         goto exit;
1340                 }
1341                 dev_warn(dev, "invalid notification: %x\n", data->iin_buffer[0]);
1342                 break;
1343         case -EOVERFLOW:
1344                 dev_err(dev, "overflow with length %d, actual length is %d\n",
1345                         data->iin_wMaxPacketSize, urb->actual_length);
1346         case -ECONNRESET:
1347         case -ENOENT:
1348         case -ESHUTDOWN:
1349         case -EILSEQ:
1350         case -ETIME:
1351                 /* urb terminated, clean up */
1352                 dev_dbg(dev, "urb terminated, status: %d\n", status);
1353                 return;
1354         default:
1355                 dev_err(dev, "unknown status received: %d\n", status);
1356         }
1357 exit:
1358         rv = usb_submit_urb(urb, GFP_ATOMIC);
1359         if (rv)
1360                 dev_err(dev, "usb_submit_urb failed: %d\n", rv);
1361 }
1362
1363 static void usbtmc_free_int(struct usbtmc_device_data *data)
1364 {
1365         if (!data->iin_ep_present || !data->iin_urb)
1366                 return;
1367         usb_kill_urb(data->iin_urb);
1368         kfree(data->iin_buffer);
1369         usb_free_urb(data->iin_urb);
1370         kref_put(&data->kref, usbtmc_delete);
1371 }
1372
1373 static int usbtmc_probe(struct usb_interface *intf,
1374                         const struct usb_device_id *id)
1375 {
1376         struct usbtmc_device_data *data;
1377         struct usb_host_interface *iface_desc;
1378         struct usb_endpoint_descriptor *endpoint;
1379         int n;
1380         int retcode;
1381
1382         dev_dbg(&intf->dev, "%s called\n", __func__);
1383
1384         data = kzalloc(sizeof(*data), GFP_KERNEL);
1385         if (!data)
1386                 return -ENOMEM;
1387
1388         data->intf = intf;
1389         data->id = id;
1390         data->usb_dev = usb_get_dev(interface_to_usbdev(intf));
1391         usb_set_intfdata(intf, data);
1392         kref_init(&data->kref);
1393         mutex_init(&data->io_mutex);
1394         init_waitqueue_head(&data->waitq);
1395         atomic_set(&data->iin_data_valid, 0);
1396         atomic_set(&data->srq_asserted, 0);
1397         data->zombie = 0;
1398
1399         /* Determine if it is a Rigol or not */
1400         data->rigol_quirk = 0;
1401         dev_dbg(&intf->dev, "Trying to find if device Vendor 0x%04X Product 0x%04X has the RIGOL quirk\n",
1402                 le16_to_cpu(data->usb_dev->descriptor.idVendor),
1403                 le16_to_cpu(data->usb_dev->descriptor.idProduct));
1404         for(n = 0; usbtmc_id_quirk[n].idVendor > 0; n++) {
1405                 if ((usbtmc_id_quirk[n].idVendor == le16_to_cpu(data->usb_dev->descriptor.idVendor)) &&
1406                     (usbtmc_id_quirk[n].idProduct == le16_to_cpu(data->usb_dev->descriptor.idProduct))) {
1407                         dev_dbg(&intf->dev, "Setting this device as having the RIGOL quirk\n");
1408                         data->rigol_quirk = 1;
1409                         break;
1410                 }
1411         }
1412
1413         /* Initialize USBTMC bTag and other fields */
1414         data->bTag      = 1;
1415         data->TermCharEnabled = 0;
1416         data->TermChar = '\n';
1417         /*  2 <= bTag <= 127   USBTMC-USB488 subclass specification 4.3.1 */
1418         data->iin_bTag = 2;
1419
1420         /* USBTMC devices have only one setting, so use that */
1421         iface_desc = data->intf->cur_altsetting;
1422         data->ifnum = iface_desc->desc.bInterfaceNumber;
1423
1424         /* Find bulk in endpoint */
1425         for (n = 0; n < iface_desc->desc.bNumEndpoints; n++) {
1426                 endpoint = &iface_desc->endpoint[n].desc;
1427
1428                 if (usb_endpoint_is_bulk_in(endpoint)) {
1429                         data->bulk_in = endpoint->bEndpointAddress;
1430                         dev_dbg(&intf->dev, "Found bulk in endpoint at %u\n",
1431                                 data->bulk_in);
1432                         break;
1433                 }
1434         }
1435
1436         /* Find bulk out endpoint */
1437         for (n = 0; n < iface_desc->desc.bNumEndpoints; n++) {
1438                 endpoint = &iface_desc->endpoint[n].desc;
1439
1440                 if (usb_endpoint_is_bulk_out(endpoint)) {
1441                         data->bulk_out = endpoint->bEndpointAddress;
1442                         dev_dbg(&intf->dev, "Found Bulk out endpoint at %u\n",
1443                                 data->bulk_out);
1444                         break;
1445                 }
1446         }
1447
1448         if (!data->bulk_out || !data->bulk_in) {
1449                 dev_err(&intf->dev, "bulk endpoints not found\n");
1450                 retcode = -ENODEV;
1451                 goto err_put;
1452         }
1453
1454         /* Find int endpoint */
1455         for (n = 0; n < iface_desc->desc.bNumEndpoints; n++) {
1456                 endpoint = &iface_desc->endpoint[n].desc;
1457
1458                 if (usb_endpoint_is_int_in(endpoint)) {
1459                         data->iin_ep_present = 1;
1460                         data->iin_ep = endpoint->bEndpointAddress;
1461                         data->iin_wMaxPacketSize = usb_endpoint_maxp(endpoint);
1462                         data->iin_interval = endpoint->bInterval;
1463                         dev_dbg(&intf->dev, "Found Int in endpoint at %u\n",
1464                                 data->iin_ep);
1465                         break;
1466                 }
1467         }
1468
1469         retcode = get_capabilities(data);
1470         if (retcode)
1471                 dev_err(&intf->dev, "can't read capabilities\n");
1472         else
1473                 retcode = sysfs_create_group(&intf->dev.kobj,
1474                                              &capability_attr_grp);
1475
1476         if (data->iin_ep_present) {
1477                 /* allocate int urb */
1478                 data->iin_urb = usb_alloc_urb(0, GFP_KERNEL);
1479                 if (!data->iin_urb) {
1480                         retcode = -ENOMEM;
1481                         goto error_register;
1482                 }
1483
1484                 /* Protect interrupt in endpoint data until iin_urb is freed */
1485                 kref_get(&data->kref);
1486
1487                 /* allocate buffer for interrupt in */
1488                 data->iin_buffer = kmalloc(data->iin_wMaxPacketSize,
1489                                         GFP_KERNEL);
1490                 if (!data->iin_buffer) {
1491                         retcode = -ENOMEM;
1492                         goto error_register;
1493                 }
1494
1495                 /* fill interrupt urb */
1496                 usb_fill_int_urb(data->iin_urb, data->usb_dev,
1497                                 usb_rcvintpipe(data->usb_dev, data->iin_ep),
1498                                 data->iin_buffer, data->iin_wMaxPacketSize,
1499                                 usbtmc_interrupt,
1500                                 data, data->iin_interval);
1501
1502                 retcode = usb_submit_urb(data->iin_urb, GFP_KERNEL);
1503                 if (retcode) {
1504                         dev_err(&intf->dev, "Failed to submit iin_urb\n");
1505                         goto error_register;
1506                 }
1507         }
1508
1509         retcode = sysfs_create_group(&intf->dev.kobj, &data_attr_grp);
1510
1511         retcode = usb_register_dev(intf, &usbtmc_class);
1512         if (retcode) {
1513                 dev_err(&intf->dev, "Not able to get a minor"
1514                         " (base %u, slice default): %d\n", USBTMC_MINOR_BASE,
1515                         retcode);
1516                 goto error_register;
1517         }
1518         dev_dbg(&intf->dev, "Using minor number %d\n", intf->minor);
1519
1520         return 0;
1521
1522 error_register:
1523         sysfs_remove_group(&intf->dev.kobj, &capability_attr_grp);
1524         sysfs_remove_group(&intf->dev.kobj, &data_attr_grp);
1525         usbtmc_free_int(data);
1526 err_put:
1527         kref_put(&data->kref, usbtmc_delete);
1528         return retcode;
1529 }
1530
1531 static void usbtmc_disconnect(struct usb_interface *intf)
1532 {
1533         struct usbtmc_device_data *data;
1534
1535         dev_dbg(&intf->dev, "usbtmc_disconnect called\n");
1536
1537         data = usb_get_intfdata(intf);
1538         usb_deregister_dev(intf, &usbtmc_class);
1539         sysfs_remove_group(&intf->dev.kobj, &capability_attr_grp);
1540         sysfs_remove_group(&intf->dev.kobj, &data_attr_grp);
1541         mutex_lock(&data->io_mutex);
1542         data->zombie = 1;
1543         wake_up_all(&data->waitq);
1544         mutex_unlock(&data->io_mutex);
1545         usbtmc_free_int(data);
1546         kref_put(&data->kref, usbtmc_delete);
1547 }
1548
1549 static int usbtmc_suspend(struct usb_interface *intf, pm_message_t message)
1550 {
1551         /* this driver does not have pending URBs */
1552         return 0;
1553 }
1554
1555 static int usbtmc_resume(struct usb_interface *intf)
1556 {
1557         return 0;
1558 }
1559
1560 static struct usb_driver usbtmc_driver = {
1561         .name           = "usbtmc",
1562         .id_table       = usbtmc_devices,
1563         .probe          = usbtmc_probe,
1564         .disconnect     = usbtmc_disconnect,
1565         .suspend        = usbtmc_suspend,
1566         .resume         = usbtmc_resume,
1567 };
1568
1569 module_usb_driver(usbtmc_driver);
1570
1571 MODULE_LICENSE("GPL");