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