drivers/usb/misc/iowarrior.c

   1 /*
   2  *  Native support for the I/O-Warrior USB devices
   3  *
   4  *  Copyright (c) 2003-2005, 2020  Code Mercenaries GmbH
   5  *  written by Christian Lucht <lucht@codemercs.com> and
   6  *  Christoph Jung <jung@codemercs.com>
   7  *
   8  *  based on
   9
  10  *  usb-skeleton.c by Greg Kroah-Hartman  <greg@kroah.com>
  11  *  brlvger.c by Stephane Dalton  <sdalton@videotron.ca>
  12  *           and St�hane Doyon   <s.doyon@videotron.ca>
  13  *
  14  *  Released under the GPLv2.
  15  */
  16
  17 #include <linux/module.h>
  18 #include <linux/usb.h>
  19 #include <linux/slab.h>
  20 #include <linux/sched.h>
  21 #include <linux/mutex.h>
  22 #include <linux/poll.h>
  23 #include <linux/usb/iowarrior.h>
  24
  25 #define DRIVER_AUTHOR "Christian Lucht <lucht@codemercs.com>"
  26 #define DRIVER_DESC "USB IO-Warrior driver"
  27
  28 #define USB_VENDOR_ID_CODEMERCS         1984
  29 /* low speed iowarrior */
  30 #define USB_DEVICE_ID_CODEMERCS_IOW40   0x1500
  31 #define USB_DEVICE_ID_CODEMERCS_IOW24   0x1501
  32 #define USB_DEVICE_ID_CODEMERCS_IOWPV1  0x1511
  33 #define USB_DEVICE_ID_CODEMERCS_IOWPV2  0x1512
  34 /* full speed iowarrior */
  35 #define USB_DEVICE_ID_CODEMERCS_IOW56   0x1503
  36 /* fuller speed iowarrior */
  37 #define USB_DEVICE_ID_CODEMERCS_IOW28   0x1504
  38 #define USB_DEVICE_ID_CODEMERCS_IOW28L  0x1505
  39 #define USB_DEVICE_ID_CODEMERCS_IOW100  0x1506
  40
  41 /* OEMed devices */
  42 #define USB_DEVICE_ID_CODEMERCS_IOW24SAG        0x158a
  43 #define USB_DEVICE_ID_CODEMERCS_IOW56AM         0x158b
  44
  45 /* Get a minor range for your devices from the usb maintainer */
  46 #ifdef CONFIG_USB_DYNAMIC_MINORS
  47 #define IOWARRIOR_MINOR_BASE    0
  48 #else
  49 #define IOWARRIOR_MINOR_BASE    208     // SKELETON_MINOR_BASE 192 + 16, not official yet
  50 #endif
  51
  52 /* interrupt input queue size */
  53 #define MAX_INTERRUPT_BUFFER 16
  54 /*
  55    maximum number of urbs that are submitted for writes at the same time,
  56    this applies to the IOWarrior56 only!
  57    IOWarrior24 and IOWarrior40 use synchronous usb_control_msg calls.
  58 */
  59 #define MAX_WRITES_IN_FLIGHT 4
  60
  61 MODULE_AUTHOR(DRIVER_AUTHOR);
  62 MODULE_DESCRIPTION(DRIVER_DESC);
  63 MODULE_LICENSE("GPL");
  64
  65 /* Module parameters */
  66 static DEFINE_MUTEX(iowarrior_mutex);
  67
  68 static struct usb_driver iowarrior_driver;
  69 static DEFINE_MUTEX(iowarrior_open_disc_lock);
  70
  71 /*--------------*/
  72 /*     data     */
  73 /*--------------*/
  74
  75 /* Structure to hold all of our device specific stuff */
  76 struct iowarrior {
  77         struct mutex mutex;                     /* locks this structure */
  78         struct usb_device *udev;                /* save off the usb device pointer */
  79         struct usb_interface *interface;        /* the interface for this device */
  80         unsigned char minor;                    /* the starting minor number for this device */
  81         struct usb_endpoint_descriptor *int_out_endpoint;       /* endpoint for reading (needed for IOW56 only) */
  82         struct usb_endpoint_descriptor *int_in_endpoint;        /* endpoint for reading */
  83         struct urb *int_in_urb;         /* the urb for reading data */
  84         unsigned char *int_in_buffer;   /* buffer for data to be read */
  85         unsigned char serial_number;    /* to detect lost packages */
  86         unsigned char *read_queue;      /* size is MAX_INTERRUPT_BUFFER * packet size */
  87         wait_queue_head_t read_wait;
  88         wait_queue_head_t write_wait;   /* wait-queue for writing to the device */
  89         atomic_t write_busy;            /* number of write-urbs submitted */
  90         atomic_t read_idx;
  91         atomic_t intr_idx;
  92         spinlock_t intr_idx_lock;       /* protects intr_idx */
  93         atomic_t overflow_flag;         /* signals an index 'rollover' */
  94         int present;                    /* this is 1 as long as the device is connected */
  95         int opened;                     /* this is 1 if the device is currently open */
  96         char chip_serial[9];            /* the serial number string of the chip connected */
  97         int report_size;                /* number of bytes in a report */
  98         u16 product_id;
  99         struct usb_anchor submitted;
 100 };
 101
 102 /*--------------*/
 103 /*    globals   */
 104 /*--------------*/
 105
 106 /*
 107  *  USB spec identifies 5 second timeouts.
 108  */
 109 #define GET_TIMEOUT 5
 110 #define USB_REQ_GET_REPORT  0x01
 111 //#if 0
 112 static int usb_get_report(struct usb_device *dev,
 113                           struct usb_host_interface *inter, unsigned char type,
 114                           unsigned char id, void *buf, int size)
 115 {
 116         return usb_control_msg(dev, usb_rcvctrlpipe(dev, 0),
 117                                USB_REQ_GET_REPORT,
 118                                USB_DIR_IN | USB_TYPE_CLASS |
 119                                USB_RECIP_INTERFACE, (type << 8) + id,
 120                                inter->desc.bInterfaceNumber, buf, size,
 121                                GET_TIMEOUT*HZ);
 122 }
 123 //#endif
 124
 125 #define USB_REQ_SET_REPORT 0x09
 126
 127 static int usb_set_report(struct usb_interface *intf, unsigned char type,
 128                           unsigned char id, void *buf, int size)
 129 {
 130         return usb_control_msg(interface_to_usbdev(intf),
 131                                usb_sndctrlpipe(interface_to_usbdev(intf), 0),
 132                                USB_REQ_SET_REPORT,
 133                                USB_TYPE_CLASS | USB_RECIP_INTERFACE,
 134                                (type << 8) + id,
 135                                intf->cur_altsetting->desc.bInterfaceNumber, buf,
 136                                size, HZ);
 137 }
 138
 139 /*---------------------*/
 140 /* driver registration */
 141 /*---------------------*/
 142 /* table of devices that work with this driver */
 143 static const struct usb_device_id iowarrior_ids[] = {
 144         {USB_DEVICE(USB_VENDOR_ID_CODEMERCS, USB_DEVICE_ID_CODEMERCS_IOW40)},
 145         {USB_DEVICE(USB_VENDOR_ID_CODEMERCS, USB_DEVICE_ID_CODEMERCS_IOW24)},
 146         {USB_DEVICE(USB_VENDOR_ID_CODEMERCS, USB_DEVICE_ID_CODEMERCS_IOWPV1)},
 147         {USB_DEVICE(USB_VENDOR_ID_CODEMERCS, USB_DEVICE_ID_CODEMERCS_IOWPV2)},
 148         {USB_DEVICE(USB_VENDOR_ID_CODEMERCS, USB_DEVICE_ID_CODEMERCS_IOW56)},
 149         {USB_DEVICE(USB_VENDOR_ID_CODEMERCS, USB_DEVICE_ID_CODEMERCS_IOW24SAG)},
 150         {USB_DEVICE(USB_VENDOR_ID_CODEMERCS, USB_DEVICE_ID_CODEMERCS_IOW56AM)},
 151         {USB_DEVICE(USB_VENDOR_ID_CODEMERCS, USB_DEVICE_ID_CODEMERCS_IOW28)},
 152         {USB_DEVICE(USB_VENDOR_ID_CODEMERCS, USB_DEVICE_ID_CODEMERCS_IOW28L)},
 153         {USB_DEVICE(USB_VENDOR_ID_CODEMERCS, USB_DEVICE_ID_CODEMERCS_IOW100)},
 154         {}                      /* Terminating entry */
 155 };
 156 MODULE_DEVICE_TABLE(usb, iowarrior_ids);
 157
 158 /*
 159  * USB callback handler for reading data
 160  */
 161 static void iowarrior_callback(struct urb *urb)
 162 {
 163         struct iowarrior *dev = urb->context;
 164         int intr_idx;
 165         int read_idx;
 166         int aux_idx;
 167         int offset;
 168         int status = urb->status;
 169         int retval;
 170
 171         switch (status) {
 172         case 0:
 173                 /* success */
 174                 break;
 175         case -ECONNRESET:
 176         case -ENOENT:
 177         case -ESHUTDOWN:
 178                 return;
 179         default:
 180                 goto exit;
 181         }
 182
 183         spin_lock(&dev->intr_idx_lock);
 184         intr_idx = atomic_read(&dev->intr_idx);
 185         /* aux_idx become previous intr_idx */
 186         aux_idx = (intr_idx == 0) ? (MAX_INTERRUPT_BUFFER - 1) : (intr_idx - 1);
 187         read_idx = atomic_read(&dev->read_idx);
 188
 189         /* queue is not empty and it's interface 0 */
 190         if ((intr_idx != read_idx)
 191             && (dev->interface->cur_altsetting->desc.bInterfaceNumber == 0)) {
 192                 /* + 1 for serial number */
 193                 offset = aux_idx * (dev->report_size + 1);
 194                 if (!memcmp
 195                     (dev->read_queue + offset, urb->transfer_buffer,
 196                      dev->report_size)) {
 197                         /* equal values on interface 0 will be ignored */
 198                         spin_unlock(&dev->intr_idx_lock);
 199                         goto exit;
 200                 }
 201         }
 202
 203         /* aux_idx become next intr_idx */
 204         aux_idx = (intr_idx == (MAX_INTERRUPT_BUFFER - 1)) ? 0 : (intr_idx + 1);
 205         if (read_idx == aux_idx) {
 206                 /* queue full, dropping oldest input */
 207                 read_idx = (++read_idx == MAX_INTERRUPT_BUFFER) ? 0 : read_idx;
 208                 atomic_set(&dev->read_idx, read_idx);
 209                 atomic_set(&dev->overflow_flag, 1);
 210         }
 211
 212         /* +1 for serial number */
 213         offset = intr_idx * (dev->report_size + 1);
 214         memcpy(dev->read_queue + offset, urb->transfer_buffer,
 215                dev->report_size);
 216         *(dev->read_queue + offset + (dev->report_size)) = dev->serial_number++;
 217
 218         atomic_set(&dev->intr_idx, aux_idx);
 219         spin_unlock(&dev->intr_idx_lock);
 220         /* tell the blocking read about the new data */
 221         wake_up_interruptible(&dev->read_wait);
 222
 223 exit:
 224         retval = usb_submit_urb(urb, GFP_ATOMIC);
 225         if (retval)
 226                 dev_err(&dev->interface->dev, "%s - usb_submit_urb failed with result %d\n",
 227                         __func__, retval);
 228
 229 }
 230
 231 /*
 232  * USB Callback handler for write-ops
 233  */
 234 static void iowarrior_write_callback(struct urb *urb)
 235 {
 236         struct iowarrior *dev;
 237         int status = urb->status;
 238
 239         dev = urb->context;
 240         /* sync/async unlink faults aren't errors */
 241         if (status &&
 242             !(status == -ENOENT ||
 243               status == -ECONNRESET || status == -ESHUTDOWN)) {
 244                 dev_dbg(&dev->interface->dev,
 245                         "nonzero write bulk status received: %d\n", status);
 246         }
 247         /* free up our allocated buffer */
 248         usb_free_coherent(urb->dev, urb->transfer_buffer_length,
 249                           urb->transfer_buffer, urb->transfer_dma);
 250         /* tell a waiting writer the interrupt-out-pipe is available again */
 251         atomic_dec(&dev->write_busy);
 252         wake_up_interruptible(&dev->write_wait);
 253 }
 254
 255 /**
 256  *      iowarrior_delete
 257  */
 258 static inline void iowarrior_delete(struct iowarrior *dev)
 259 {
 260         dev_dbg(&dev->interface->dev, "minor %d\n", dev->minor);
 261         kfree(dev->int_in_buffer);
 262         usb_free_urb(dev->int_in_urb);
 263         kfree(dev->read_queue);
 264         usb_put_intf(dev->interface);
 265         kfree(dev);
 266 }
 267
 268 /*---------------------*/
 269 /* fops implementation */
 270 /*---------------------*/
 271
 272 static int read_index(struct iowarrior *dev)
 273 {
 274         int intr_idx, read_idx;
 275
 276         read_idx = atomic_read(&dev->read_idx);
 277         intr_idx = atomic_read(&dev->intr_idx);
 278
 279         return (read_idx == intr_idx ? -1 : read_idx);
 280 }
 281
 282 /**
 283  *  iowarrior_read
 284  */
 285 static ssize_t iowarrior_read(struct file *file, char __user *buffer,
 286                               size_t count, loff_t *ppos)
 287 {
 288         struct iowarrior *dev;
 289         int read_idx;
 290         int offset;
 291
 292         dev = file->private_data;
 293
 294         /* verify that the device wasn't unplugged */
 295         if (!dev || !dev->present)
 296                 return -ENODEV;
 297
 298         dev_dbg(&dev->interface->dev, "minor %d, count = %zd\n",
 299                 dev->minor, count);
 300
 301         /* read count must be packet size (+ time stamp) */
 302         if ((count != dev->report_size)
 303             && (count != (dev->report_size + 1)))
 304                 return -EINVAL;
 305
 306         /* repeat until no buffer overrun in callback handler occur */
 307         do {
 308                 atomic_set(&dev->overflow_flag, 0);
 309                 if ((read_idx = read_index(dev)) == -1) {
 310                         /* queue empty */
 311                         if (file->f_flags & O_NONBLOCK)
 312                                 return -EAGAIN;
 313                         else {
 314                                 //next line will return when there is either new data, or the device is unplugged
 315                                 int r = wait_event_interruptible(dev->read_wait,
 316                                                                  (!dev->present
 317                                                                   || (read_idx =
 318                                                                       read_index
 319                                                                       (dev)) !=
 320                                                                   -1));
 321                                 if (r) {
 322                                         //we were interrupted by a signal
 323                                         return -ERESTART;
 324                                 }
 325                                 if (!dev->present) {
 326                                         //The device was unplugged
 327                                         return -ENODEV;
 328                                 }
 329                                 if (read_idx == -1) {
 330                                         // Can this happen ???
 331                                         return 0;
 332                                 }
 333                         }
 334                 }
 335
 336                 offset = read_idx * (dev->report_size + 1);
 337                 if (copy_to_user(buffer, dev->read_queue + offset, count)) {
 338                         return -EFAULT;
 339                 }
 340         } while (atomic_read(&dev->overflow_flag));
 341
 342         read_idx = ++read_idx == MAX_INTERRUPT_BUFFER ? 0 : read_idx;
 343         atomic_set(&dev->read_idx, read_idx);
 344         return count;
 345 }
 346
 347 /*
 348  * iowarrior_write
 349  */
 350 static ssize_t iowarrior_write(struct file *file,
 351                                const char __user *user_buffer,
 352                                size_t count, loff_t *ppos)
 353 {
 354         struct iowarrior *dev;
 355         int retval = 0;
 356         char *buf = NULL;       /* for IOW24 and IOW56 we need a buffer */
 357         struct urb *int_out_urb = NULL;
 358
 359         dev = file->private_data;
 360
 361         mutex_lock(&dev->mutex);
 362         /* verify that the device wasn't unplugged */
 363         if (!dev->present) {
 364                 retval = -ENODEV;
 365                 goto exit;
 366         }
 367         dev_dbg(&dev->interface->dev, "minor %d, count = %zd\n",
 368                 dev->minor, count);
 369         /* if count is 0 we're already done */
 370         if (count == 0) {
 371                 retval = 0;
 372                 goto exit;
 373         }
 374         /* We only accept full reports */
 375         if (count != dev->report_size) {
 376                 retval = -EINVAL;
 377                 goto exit;
 378         }
 379         switch (dev->product_id) {
 380         case USB_DEVICE_ID_CODEMERCS_IOW24:
 381         case USB_DEVICE_ID_CODEMERCS_IOW24SAG:
 382         case USB_DEVICE_ID_CODEMERCS_IOWPV1:
 383         case USB_DEVICE_ID_CODEMERCS_IOWPV2:
 384         case USB_DEVICE_ID_CODEMERCS_IOW40:
 385                 /* IOW24 and IOW40 use a synchronous call */
 386                 buf = memdup_user(user_buffer, count);
 387                 if (IS_ERR(buf)) {
 388                         retval = PTR_ERR(buf);
 389                         goto exit;
 390                 }
 391                 retval = usb_set_report(dev->interface, 2, 0, buf, count);
 392                 kfree(buf);
 393                 goto exit;
 394                 break;
 395         case USB_DEVICE_ID_CODEMERCS_IOW56:
 396         case USB_DEVICE_ID_CODEMERCS_IOW56AM:
 397         case USB_DEVICE_ID_CODEMERCS_IOW28:
 398         case USB_DEVICE_ID_CODEMERCS_IOW28L:
 399         case USB_DEVICE_ID_CODEMERCS_IOW100:
 400                 /* The IOW56 uses asynchronous IO and more urbs */
 401                 if (atomic_read(&dev->write_busy) == MAX_WRITES_IN_FLIGHT) {
 402                         /* Wait until we are below the limit for submitted urbs */
 403                         if (file->f_flags & O_NONBLOCK) {
 404                                 retval = -EAGAIN;
 405                                 goto exit;
 406                         } else {
 407                                 retval = wait_event_interruptible(dev->write_wait,
 408                                                                   (!dev->present || (atomic_read (&dev-> write_busy) < MAX_WRITES_IN_FLIGHT)));
 409                                 if (retval) {
 410                                         /* we were interrupted by a signal */
 411                                         retval = -ERESTART;
 412                                         goto exit;
 413                                 }
 414                                 if (!dev->present) {
 415                                         /* The device was unplugged */
 416                                         retval = -ENODEV;
 417                                         goto exit;
 418                                 }
 419                                 if (!dev->opened) {
 420                                         /* We were closed while waiting for an URB */
 421                                         retval = -ENODEV;
 422                                         goto exit;
 423                                 }
 424                         }
 425                 }
 426                 atomic_inc(&dev->write_busy);
 427                 int_out_urb = usb_alloc_urb(0, GFP_KERNEL);
 428                 if (!int_out_urb) {
 429                         retval = -ENOMEM;
 430                         goto error_no_urb;
 431                 }
 432                 buf = usb_alloc_coherent(dev->udev, dev->report_size,
 433                                          GFP_KERNEL, &int_out_urb->transfer_dma);
 434                 if (!buf) {
 435                         retval = -ENOMEM;
 436                         dev_dbg(&dev->interface->dev,
 437                                 "Unable to allocate buffer\n");
 438                         goto error_no_buffer;
 439                 }
 440                 usb_fill_int_urb(int_out_urb, dev->udev,
 441                                  usb_sndintpipe(dev->udev,
 442                                                 dev->int_out_endpoint->bEndpointAddress),
 443                                  buf, dev->report_size,
 444                                  iowarrior_write_callback, dev,
 445                                  dev->int_out_endpoint->bInterval);
 446                 int_out_urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
 447                 if (copy_from_user(buf, user_buffer, count)) {
 448                         retval = -EFAULT;
 449                         goto error;
 450                 }
 451                 usb_anchor_urb(int_out_urb, &dev->submitted);
 452                 retval = usb_submit_urb(int_out_urb, GFP_KERNEL);
 453                 if (retval) {
 454                         dev_dbg(&dev->interface->dev,
 455                                 "submit error %d for urb nr.%d\n",
 456                                 retval, atomic_read(&dev->write_busy));
 457                         usb_unanchor_urb(int_out_urb);
 458                         goto error;
 459                 }
 460                 /* submit was ok */
 461                 retval = count;
 462                 usb_free_urb(int_out_urb);
 463                 goto exit;
 464                 break;
 465         default:
 466                 /* what do we have here ? An unsupported Product-ID ? */
 467                 dev_err(&dev->interface->dev, "%s - not supported for product=0x%x\n",
 468                         __func__, dev->product_id);
 469                 retval = -EFAULT;
 470                 goto exit;
 471                 break;
 472         }
 473 error:
 474         usb_free_coherent(dev->udev, dev->report_size, buf,
 475                           int_out_urb->transfer_dma);
 476 error_no_buffer:
 477         usb_free_urb(int_out_urb);
 478 error_no_urb:
 479         atomic_dec(&dev->write_busy);
 480         wake_up_interruptible(&dev->write_wait);
 481 exit:
 482         mutex_unlock(&dev->mutex);
 483         return retval;
 484 }
 485
 486 /**
 487  *      iowarrior_ioctl
 488  */
 489 static long iowarrior_ioctl(struct file *file, unsigned int cmd,
 490                                                         unsigned long arg)
 491 {
 492         struct iowarrior *dev = NULL;
 493         __u8 *buffer;
 494         __u8 __user *user_buffer;
 495         int retval;
 496         int io_res;             /* checks for bytes read/written and copy_to/from_user results */
 497
 498         dev = file->private_data;
 499         if (!dev)
 500                 return -ENODEV;
 501
 502         buffer = kzalloc(dev->report_size, GFP_KERNEL);
 503         if (!buffer)
 504                 return -ENOMEM;
 505
 506         /* lock this object */
 507         mutex_lock(&iowarrior_mutex);
 508         mutex_lock(&dev->mutex);
 509
 510         /* verify that the device wasn't unplugged */
 511         if (!dev->present) {
 512                 retval = -ENODEV;
 513                 goto error_out;
 514         }
 515
 516         dev_dbg(&dev->interface->dev, "minor %d, cmd 0x%.4x, arg %ld\n",
 517                 dev->minor, cmd, arg);
 518
 519         retval = 0;
 520         io_res = 0;
 521         switch (cmd) {
 522         case IOW_WRITE:
 523                 if (dev->product_id == USB_DEVICE_ID_CODEMERCS_IOW24 ||
 524                     dev->product_id == USB_DEVICE_ID_CODEMERCS_IOW24SAG ||
 525                     dev->product_id == USB_DEVICE_ID_CODEMERCS_IOWPV1 ||
 526                     dev->product_id == USB_DEVICE_ID_CODEMERCS_IOWPV2 ||
 527                     dev->product_id == USB_DEVICE_ID_CODEMERCS_IOW40) {
 528                         user_buffer = (__u8 __user *)arg;
 529                         io_res = copy_from_user(buffer, user_buffer,
 530                                                 dev->report_size);
 531                         if (io_res) {
 532                                 retval = -EFAULT;
 533                         } else {
 534                                 io_res = usb_set_report(dev->interface, 2, 0,
 535                                                         buffer,
 536                                                         dev->report_size);
 537                                 if (io_res < 0)
 538                                         retval = io_res;
 539                         }
 540                 } else {
 541                         retval = -EINVAL;
 542                         dev_err(&dev->interface->dev,
 543                                 "ioctl 'IOW_WRITE' is not supported for product=0x%x.\n",
 544                                 dev->product_id);
 545                 }
 546                 break;
 547         case IOW_READ:
 548                 user_buffer = (__u8 __user *)arg;
 549                 io_res = usb_get_report(dev->udev,
 550                                         dev->interface->cur_altsetting, 1, 0,
 551                                         buffer, dev->report_size);
 552                 if (io_res < 0)
 553                         retval = io_res;
 554                 else {
 555                         io_res = copy_to_user(user_buffer, buffer, dev->report_size);
 556                         if (io_res)
 557                                 retval = -EFAULT;
 558                 }
 559                 break;
 560         case IOW_GETINFO:
 561                 {
 562                         /* Report available information for the device */
 563                         struct iowarrior_info info;
 564                         /* needed for power consumption */
 565                         struct usb_config_descriptor *cfg_descriptor = &dev->udev->actconfig->desc;
 566
 567                         memset(&info, 0, sizeof(info));
 568                         /* directly from the descriptor */
 569                         info.vendor = le16_to_cpu(dev->udev->descriptor.idVendor);
 570                         info.product = dev->product_id;
 571                         info.revision = le16_to_cpu(dev->udev->descriptor.bcdDevice);
 572
 573                         /* 0==UNKNOWN, 1==LOW(usb1.1) ,2=FULL(usb1.1), 3=HIGH(usb2.0) */
 574                         info.speed = dev->udev->speed;
 575                         info.if_num = dev->interface->cur_altsetting->desc.bInterfaceNumber;
 576                         info.report_size = dev->report_size;
 577
 578                         /* serial number string has been read earlier 8 chars or empty string */
 579                         memcpy(info.serial, dev->chip_serial,
 580                                sizeof(dev->chip_serial));
 581                         if (cfg_descriptor == NULL) {
 582                                 info.power = -1;        /* no information available */
 583                         } else {
 584                                 /* the MaxPower is stored in units of 2mA to make it fit into a byte-value */
 585                                 info.power = cfg_descriptor->bMaxPower * 2;
 586                         }
 587                         io_res = copy_to_user((struct iowarrior_info __user *)arg, &info,
 588                                          sizeof(struct iowarrior_info));
 589                         if (io_res)
 590                                 retval = -EFAULT;
 591                         break;
 592                 }
 593         default:
 594                 /* return that we did not understand this ioctl call */
 595                 retval = -ENOTTY;
 596                 break;
 597         }
 598 error_out:
 599         /* unlock the device */
 600         mutex_unlock(&dev->mutex);
 601         mutex_unlock(&iowarrior_mutex);
 602         kfree(buffer);
 603         return retval;
 604 }
 605
 606 /**
 607  *      iowarrior_open
 608  */
 609 static int iowarrior_open(struct inode *inode, struct file *file)
 610 {
 611         struct iowarrior *dev = NULL;
 612         struct usb_interface *interface;
 613         int subminor;
 614         int retval = 0;
 615
 616         mutex_lock(&iowarrior_mutex);
 617         subminor = iminor(inode);
 618
 619         interface = usb_find_interface(&iowarrior_driver, subminor);
 620         if (!interface) {
 621                 mutex_unlock(&iowarrior_mutex);
 622                 printk(KERN_ERR "%s - error, can't find device for minor %d\n",
 623                        __func__, subminor);
 624                 return -ENODEV;
 625         }
 626
 627         mutex_lock(&iowarrior_open_disc_lock);
 628         dev = usb_get_intfdata(interface);
 629         if (!dev) {
 630                 mutex_unlock(&iowarrior_open_disc_lock);
 631                 mutex_unlock(&iowarrior_mutex);
 632                 return -ENODEV;
 633         }
 634
 635         mutex_lock(&dev->mutex);
 636         mutex_unlock(&iowarrior_open_disc_lock);
 637
 638         /* Only one process can open each device, no sharing. */
 639         if (dev->opened) {
 640                 retval = -EBUSY;
 641                 goto out;
 642         }
 643
 644         /* setup interrupt handler for receiving values */
 645         if ((retval = usb_submit_urb(dev->int_in_urb, GFP_KERNEL)) < 0) {
 646                 dev_err(&interface->dev, "Error %d while submitting URB\n", retval);
 647                 retval = -EFAULT;
 648                 goto out;
 649         }
 650         /* increment our usage count for the driver */
 651         ++dev->opened;
 652         /* save our object in the file's private structure */
 653         file->private_data = dev;
 654         retval = 0;
 655
 656 out:
 657         mutex_unlock(&dev->mutex);
 658         mutex_unlock(&iowarrior_mutex);
 659         return retval;
 660 }
 661
 662 /**
 663  *      iowarrior_release
 664  */
 665 static int iowarrior_release(struct inode *inode, struct file *file)
 666 {
 667         struct iowarrior *dev;
 668         int retval = 0;
 669
 670         dev = file->private_data;
 671         if (!dev)
 672                 return -ENODEV;
 673
 674         dev_dbg(&dev->interface->dev, "minor %d\n", dev->minor);
 675
 676         /* lock our device */
 677         mutex_lock(&dev->mutex);
 678
 679         if (dev->opened <= 0) {
 680                 retval = -ENODEV;       /* close called more than once */
 681                 mutex_unlock(&dev->mutex);
 682         } else {
 683                 dev->opened = 0;        /* we're closing now */
 684                 retval = 0;
 685                 if (dev->present) {
 686                         /*
 687                            The device is still connected so we only shutdown
 688                            pending read-/write-ops.
 689                          */
 690                         usb_kill_urb(dev->int_in_urb);
 691                         wake_up_interruptible(&dev->read_wait);
 692                         wake_up_interruptible(&dev->write_wait);
 693                         mutex_unlock(&dev->mutex);
 694                 } else {
 695                         /* The device was unplugged, cleanup resources */
 696                         mutex_unlock(&dev->mutex);
 697                         iowarrior_delete(dev);
 698                 }
 699         }
 700         return retval;
 701 }
 702
 703 static unsigned iowarrior_poll(struct file *file, poll_table * wait)
 704 {
 705         struct iowarrior *dev = file->private_data;
 706         unsigned int mask = 0;
 707
 708         if (!dev->present)
 709                 return POLLERR | POLLHUP;
 710
 711         poll_wait(file, &dev->read_wait, wait);
 712         poll_wait(file, &dev->write_wait, wait);
 713
 714         if (!dev->present)
 715                 return POLLERR | POLLHUP;
 716
 717         if (read_index(dev) != -1)
 718                 mask |= POLLIN | POLLRDNORM;
 719
 720         if (atomic_read(&dev->write_busy) < MAX_WRITES_IN_FLIGHT)
 721                 mask |= POLLOUT | POLLWRNORM;
 722         return mask;
 723 }
 724
 725 /*
 726  * File operations needed when we register this driver.
 727  * This assumes that this driver NEEDS file operations,
 728  * of course, which means that the driver is expected
 729  * to have a node in the /dev directory. If the USB
 730  * device were for a network interface then the driver
 731  * would use "struct net_driver" instead, and a serial
 732  * device would use "struct tty_driver".
 733  */
 734 static const struct file_operations iowarrior_fops = {
 735         .owner = THIS_MODULE,
 736         .write = iowarrior_write,
 737         .read = iowarrior_read,
 738         .unlocked_ioctl = iowarrior_ioctl,
 739         .open = iowarrior_open,
 740         .release = iowarrior_release,
 741         .poll = iowarrior_poll,
 742         .llseek = noop_llseek,
 743 };
 744
 745 static char *iowarrior_devnode(struct device *dev, umode_t *mode)
 746 {
 747         return kasprintf(GFP_KERNEL, "usb/%s", dev_name(dev));
 748 }
 749
 750 /*
 751  * usb class driver info in order to get a minor number from the usb core,
 752  * and to have the device registered with devfs and the driver core
 753  */
 754 static struct usb_class_driver iowarrior_class = {
 755         .name = "iowarrior%d",
 756         .devnode = iowarrior_devnode,
 757         .fops = &iowarrior_fops,
 758         .minor_base = IOWARRIOR_MINOR_BASE,
 759 };
 760
 761 /*---------------------------------*/
 762 /*  probe and disconnect functions */
 763 /*---------------------------------*/
 764 /**
 765  *      iowarrior_probe
 766  *
 767  *      Called by the usb core when a new device is connected that it thinks
 768  *      this driver might be interested in.
 769  */
 770 static int iowarrior_probe(struct usb_interface *interface,
 771                            const struct usb_device_id *id)
 772 {
 773         struct usb_device *udev = interface_to_usbdev(interface);
 774         struct iowarrior *dev = NULL;
 775         struct usb_host_interface *iface_desc;
 776         int retval = -ENOMEM;
 777         int res;
 778
 779         /* allocate memory for our device state and initialize it */
 780         dev = kzalloc(sizeof(struct iowarrior), GFP_KERNEL);
 781         if (!dev)
 782                 return retval;
 783
 784         mutex_init(&dev->mutex);
 785
 786         atomic_set(&dev->intr_idx, 0);
 787         atomic_set(&dev->read_idx, 0);
 788         spin_lock_init(&dev->intr_idx_lock);
 789         atomic_set(&dev->overflow_flag, 0);
 790         init_waitqueue_head(&dev->read_wait);
 791         atomic_set(&dev->write_busy, 0);
 792         init_waitqueue_head(&dev->write_wait);
 793
 794         dev->udev = udev;
 795         dev->interface = usb_get_intf(interface);
 796
 797         iface_desc = interface->cur_altsetting;
 798         dev->product_id = le16_to_cpu(udev->descriptor.idProduct);
 799
 800         init_usb_anchor(&dev->submitted);
 801
 802         res = usb_find_last_int_in_endpoint(iface_desc, &dev->int_in_endpoint);
 803         if (res) {
 804                 dev_err(&interface->dev, "no interrupt-in endpoint found\n");
 805                 retval = res;
 806                 goto error;
 807         }
 808
 809         if ((dev->product_id == USB_DEVICE_ID_CODEMERCS_IOW56) ||
 810             (dev->product_id == USB_DEVICE_ID_CODEMERCS_IOW56AM) ||
 811             (dev->product_id == USB_DEVICE_ID_CODEMERCS_IOW28) ||
 812             (dev->product_id == USB_DEVICE_ID_CODEMERCS_IOW28L) ||
 813             (dev->product_id == USB_DEVICE_ID_CODEMERCS_IOW100)) {
 814                 res = usb_find_last_int_out_endpoint(iface_desc,
 815                                 &dev->int_out_endpoint);
 816                 if (res) {
 817                         dev_err(&interface->dev, "no interrupt-out endpoint found\n");
 818                         retval = res;
 819                         goto error;
 820                 }
 821         }
 822
 823         /* we have to check the report_size often, so remember it in the endianness suitable for our machine */
 824         dev->report_size = usb_endpoint_maxp(dev->int_in_endpoint);
 825
 826         /*
 827          * Some devices need the report size to be different than the
 828          * endpoint size.
 829          */
 830         if (dev->interface->cur_altsetting->desc.bInterfaceNumber == 0) {
 831                 switch (dev->product_id) {
 832                 case USB_DEVICE_ID_CODEMERCS_IOW56:
 833                 case USB_DEVICE_ID_CODEMERCS_IOW56AM:
 834                         dev->report_size = 7;
 835                         break;
 836
 837                 case USB_DEVICE_ID_CODEMERCS_IOW28:
 838                 case USB_DEVICE_ID_CODEMERCS_IOW28L:
 839                         dev->report_size = 4;
 840                         break;
 841
 842                 case USB_DEVICE_ID_CODEMERCS_IOW100:
 843                         dev->report_size = 13;
 844                         break;
 845                 }
 846         }
 847
 848         /* create the urb and buffer for reading */
 849         dev->int_in_urb = usb_alloc_urb(0, GFP_KERNEL);
 850         if (!dev->int_in_urb)
 851                 goto error;
 852         dev->int_in_buffer = kmalloc(dev->report_size, GFP_KERNEL);
 853         if (!dev->int_in_buffer)
 854                 goto error;
 855         usb_fill_int_urb(dev->int_in_urb, dev->udev,
 856                          usb_rcvintpipe(dev->udev,
 857                                         dev->int_in_endpoint->bEndpointAddress),
 858                          dev->int_in_buffer, dev->report_size,
 859                          iowarrior_callback, dev,
 860                          dev->int_in_endpoint->bInterval);
 861         /* create an internal buffer for interrupt data from the device */
 862         dev->read_queue =
 863             kmalloc(((dev->report_size + 1) * MAX_INTERRUPT_BUFFER),
 864                     GFP_KERNEL);
 865         if (!dev->read_queue)
 866                 goto error;
 867         /* Get the serial-number of the chip */
 868         memset(dev->chip_serial, 0x00, sizeof(dev->chip_serial));
 869         usb_string(udev, udev->descriptor.iSerialNumber, dev->chip_serial,
 870                    sizeof(dev->chip_serial));
 871         if (strlen(dev->chip_serial) != 8)
 872                 memset(dev->chip_serial, 0x00, sizeof(dev->chip_serial));
 873
 874         /* Set the idle timeout to 0, if this is interface 0 */
 875         if (dev->interface->cur_altsetting->desc.bInterfaceNumber == 0) {
 876             usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
 877                             0x0A,
 878                             USB_TYPE_CLASS | USB_RECIP_INTERFACE, 0,
 879                             0, NULL, 0, USB_CTRL_SET_TIMEOUT);
 880         }
 881         /* allow device read and ioctl */
 882         dev->present = 1;
 883
 884         /* we can register the device now, as it is ready */
 885         usb_set_intfdata(interface, dev);
 886
 887         retval = usb_register_dev(interface, &iowarrior_class);
 888         if (retval) {
 889                 /* something prevented us from registering this driver */
 890                 dev_err(&interface->dev, "Not able to get a minor for this device.\n");
 891                 usb_set_intfdata(interface, NULL);
 892                 goto error;
 893         }
 894
 895         dev->minor = interface->minor;
 896
 897         /* let the user know what node this device is now attached to */
 898         dev_info(&interface->dev, "IOWarrior product=0x%x, serial=%s interface=%d "
 899                  "now attached to iowarrior%d\n", dev->product_id, dev->chip_serial,
 900                  iface_desc->desc.bInterfaceNumber, dev->minor - IOWARRIOR_MINOR_BASE);
 901         return retval;
 902
 903 error:
 904         iowarrior_delete(dev);
 905         return retval;
 906 }
 907
 908 /**
 909  *      iowarrior_disconnect
 910  *
 911  *      Called by the usb core when the device is removed from the system.
 912  */
 913 static void iowarrior_disconnect(struct usb_interface *interface)
 914 {
 915         struct iowarrior *dev;
 916         int minor;
 917
 918         dev = usb_get_intfdata(interface);
 919         mutex_lock(&iowarrior_open_disc_lock);
 920         usb_set_intfdata(interface, NULL);
 921
 922         minor = dev->minor;
 923         mutex_unlock(&iowarrior_open_disc_lock);
 924         /* give back our minor - this will call close() locks need to be dropped at this point*/
 925
 926         usb_deregister_dev(interface, &iowarrior_class);
 927
 928         mutex_lock(&dev->mutex);
 929
 930         /* prevent device read, write and ioctl */
 931         dev->present = 0;
 932
 933         if (dev->opened) {
 934                 /* There is a process that holds a filedescriptor to the device ,
 935                    so we only shutdown read-/write-ops going on.
 936                    Deleting the device is postponed until close() was called.
 937                  */
 938                 usb_kill_urb(dev->int_in_urb);
 939                 usb_kill_anchored_urbs(&dev->submitted);
 940                 wake_up_interruptible(&dev->read_wait);
 941                 wake_up_interruptible(&dev->write_wait);
 942                 mutex_unlock(&dev->mutex);
 943         } else {
 944                 /* no process is using the device, cleanup now */
 945                 mutex_unlock(&dev->mutex);
 946                 iowarrior_delete(dev);
 947         }
 948
 949         dev_info(&interface->dev, "I/O-Warror #%d now disconnected\n",
 950                  minor - IOWARRIOR_MINOR_BASE);
 951 }
 952
 953 /* usb specific object needed to register this driver with the usb subsystem */
 954 static struct usb_driver iowarrior_driver = {
 955         .name = "iowarrior",
 956         .probe = iowarrior_probe,
 957         .disconnect = iowarrior_disconnect,
 958         .id_table = iowarrior_ids,
 959 };
 960
 961 module_usb_driver(iowarrior_driver);