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