1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Native support for the I/O-Warrior USB devices 4 * 5 * Copyright (c) 2003-2005 Code Mercenaries GmbH 6 * written by Christian Lucht <lucht@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 37 /* Get a minor range for your devices from the usb maintainer */ 38 #ifdef CONFIG_USB_DYNAMIC_MINORS 39 #define IOWARRIOR_MINOR_BASE 0 40 #else 41 #define IOWARRIOR_MINOR_BASE 208 // SKELETON_MINOR_BASE 192 + 16, not official yet 42 #endif 43 44 /* interrupt input queue size */ 45 #define MAX_INTERRUPT_BUFFER 16 46 /* 47 maximum number of urbs that are submitted for writes at the same time, 48 this applies to the IOWarrior56 only! 49 IOWarrior24 and IOWarrior40 use synchronous usb_control_msg calls. 50 */ 51 #define MAX_WRITES_IN_FLIGHT 4 52 53 MODULE_AUTHOR(DRIVER_AUTHOR); 54 MODULE_DESCRIPTION(DRIVER_DESC); 55 MODULE_LICENSE("GPL"); 56 57 static struct usb_driver iowarrior_driver; 58 59 /*--------------*/ 60 /* data */ 61 /*--------------*/ 62 63 /* Structure to hold all of our device specific stuff */ 64 struct iowarrior { 65 struct mutex mutex; /* locks this structure */ 66 struct usb_device *udev; /* save off the usb device pointer */ 67 struct usb_interface *interface; /* the interface for this device */ 68 unsigned char minor; /* the starting minor number for this device */ 69 struct usb_endpoint_descriptor *int_out_endpoint; /* endpoint for reading (needed for IOW56 only) */ 70 struct usb_endpoint_descriptor *int_in_endpoint; /* endpoint for reading */ 71 struct urb *int_in_urb; /* the urb for reading data */ 72 unsigned char *int_in_buffer; /* buffer for data to be read */ 73 unsigned char serial_number; /* to detect lost packages */ 74 unsigned char *read_queue; /* size is MAX_INTERRUPT_BUFFER * packet size */ 75 wait_queue_head_t read_wait; 76 wait_queue_head_t write_wait; /* wait-queue for writing to the device */ 77 atomic_t write_busy; /* number of write-urbs submitted */ 78 atomic_t read_idx; 79 atomic_t intr_idx; 80 atomic_t overflow_flag; /* signals an index 'rollover' */ 81 int present; /* this is 1 as long as the device is connected */ 82 int opened; /* this is 1 if the device is currently open */ 83 char chip_serial[9]; /* the serial number string of the chip connected */ 84 int report_size; /* number of bytes in a report */ 85 u16 product_id; 86 struct usb_anchor submitted; 87 }; 88 89 /*--------------*/ 90 /* globals */ 91 /*--------------*/ 92 93 /* 94 * USB spec identifies 5 second timeouts. 95 */ 96 #define GET_TIMEOUT 5 97 #define USB_REQ_GET_REPORT 0x01 98 //#if 0 99 static int usb_get_report(struct usb_device *dev, 100 struct usb_host_interface *inter, unsigned char type, 101 unsigned char id, void *buf, int size) 102 { 103 return usb_control_msg(dev, usb_rcvctrlpipe(dev, 0), 104 USB_REQ_GET_REPORT, 105 USB_DIR_IN | USB_TYPE_CLASS | 106 USB_RECIP_INTERFACE, (type << 8) + id, 107 inter->desc.bInterfaceNumber, buf, size, 108 GET_TIMEOUT*HZ); 109 } 110 //#endif 111 112 #define USB_REQ_SET_REPORT 0x09 113 114 static int usb_set_report(struct usb_interface *intf, unsigned char type, 115 unsigned char id, void *buf, int size) 116 { 117 return usb_control_msg(interface_to_usbdev(intf), 118 usb_sndctrlpipe(interface_to_usbdev(intf), 0), 119 USB_REQ_SET_REPORT, 120 USB_TYPE_CLASS | USB_RECIP_INTERFACE, 121 (type << 8) + id, 122 intf->cur_altsetting->desc.bInterfaceNumber, buf, 123 size, HZ); 124 } 125 126 /*---------------------*/ 127 /* driver registration */ 128 /*---------------------*/ 129 /* table of devices that work with this driver */ 130 static const struct usb_device_id iowarrior_ids[] = { 131 {USB_DEVICE(USB_VENDOR_ID_CODEMERCS, USB_DEVICE_ID_CODEMERCS_IOW40)}, 132 {USB_DEVICE(USB_VENDOR_ID_CODEMERCS, USB_DEVICE_ID_CODEMERCS_IOW24)}, 133 {USB_DEVICE(USB_VENDOR_ID_CODEMERCS, USB_DEVICE_ID_CODEMERCS_IOWPV1)}, 134 {USB_DEVICE(USB_VENDOR_ID_CODEMERCS, USB_DEVICE_ID_CODEMERCS_IOWPV2)}, 135 {USB_DEVICE(USB_VENDOR_ID_CODEMERCS, USB_DEVICE_ID_CODEMERCS_IOW56)}, 136 {} /* Terminating entry */ 137 }; 138 MODULE_DEVICE_TABLE(usb, iowarrior_ids); 139 140 /* 141 * USB callback handler for reading data 142 */ 143 static void iowarrior_callback(struct urb *urb) 144 { 145 struct iowarrior *dev = urb->context; 146 int intr_idx; 147 int read_idx; 148 int aux_idx; 149 int offset; 150 int status = urb->status; 151 int retval; 152 153 switch (status) { 154 case 0: 155 /* success */ 156 break; 157 case -ECONNRESET: 158 case -ENOENT: 159 case -ESHUTDOWN: 160 return; 161 default: 162 goto exit; 163 } 164 165 intr_idx = atomic_read(&dev->intr_idx); 166 /* aux_idx become previous intr_idx */ 167 aux_idx = (intr_idx == 0) ? (MAX_INTERRUPT_BUFFER - 1) : (intr_idx - 1); 168 read_idx = atomic_read(&dev->read_idx); 169 170 /* queue is not empty and it's interface 0 */ 171 if ((intr_idx != read_idx) 172 && (dev->interface->cur_altsetting->desc.bInterfaceNumber == 0)) { 173 /* + 1 for serial number */ 174 offset = aux_idx * (dev->report_size + 1); 175 if (!memcmp 176 (dev->read_queue + offset, urb->transfer_buffer, 177 dev->report_size)) { 178 /* equal values on interface 0 will be ignored */ 179 goto exit; 180 } 181 } 182 183 /* aux_idx become next intr_idx */ 184 aux_idx = (intr_idx == (MAX_INTERRUPT_BUFFER - 1)) ? 0 : (intr_idx + 1); 185 if (read_idx == aux_idx) { 186 /* queue full, dropping oldest input */ 187 read_idx = (++read_idx == MAX_INTERRUPT_BUFFER) ? 0 : read_idx; 188 atomic_set(&dev->read_idx, read_idx); 189 atomic_set(&dev->overflow_flag, 1); 190 } 191 192 /* +1 for serial number */ 193 offset = intr_idx * (dev->report_size + 1); 194 memcpy(dev->read_queue + offset, urb->transfer_buffer, 195 dev->report_size); 196 *(dev->read_queue + offset + (dev->report_size)) = dev->serial_number++; 197 198 atomic_set(&dev->intr_idx, aux_idx); 199 /* tell the blocking read about the new data */ 200 wake_up_interruptible(&dev->read_wait); 201 202 exit: 203 retval = usb_submit_urb(urb, GFP_ATOMIC); 204 if (retval) 205 dev_err(&dev->interface->dev, "%s - usb_submit_urb failed with result %d\n", 206 __func__, retval); 207 208 } 209 210 /* 211 * USB Callback handler for write-ops 212 */ 213 static void iowarrior_write_callback(struct urb *urb) 214 { 215 struct iowarrior *dev; 216 int status = urb->status; 217 218 dev = urb->context; 219 /* sync/async unlink faults aren't errors */ 220 if (status && 221 !(status == -ENOENT || 222 status == -ECONNRESET || status == -ESHUTDOWN)) { 223 dev_dbg(&dev->interface->dev, 224 "nonzero write bulk status received: %d\n", status); 225 } 226 /* free up our allocated buffer */ 227 usb_free_coherent(urb->dev, urb->transfer_buffer_length, 228 urb->transfer_buffer, urb->transfer_dma); 229 /* tell a waiting writer the interrupt-out-pipe is available again */ 230 atomic_dec(&dev->write_busy); 231 wake_up_interruptible(&dev->write_wait); 232 } 233 234 /** 235 * iowarrior_delete 236 */ 237 static inline void iowarrior_delete(struct iowarrior *dev) 238 { 239 dev_dbg(&dev->interface->dev, "minor %d\n", dev->minor); 240 kfree(dev->int_in_buffer); 241 usb_free_urb(dev->int_in_urb); 242 kfree(dev->read_queue); 243 usb_put_intf(dev->interface); 244 kfree(dev); 245 } 246 247 /*---------------------*/ 248 /* fops implementation */ 249 /*---------------------*/ 250 251 static int read_index(struct iowarrior *dev) 252 { 253 int intr_idx, read_idx; 254 255 read_idx = atomic_read(&dev->read_idx); 256 intr_idx = atomic_read(&dev->intr_idx); 257 258 return (read_idx == intr_idx ? -1 : read_idx); 259 } 260 261 /** 262 * iowarrior_read 263 */ 264 static ssize_t iowarrior_read(struct file *file, char __user *buffer, 265 size_t count, loff_t *ppos) 266 { 267 struct iowarrior *dev; 268 int read_idx; 269 int offset; 270 271 dev = file->private_data; 272 273 /* verify that the device wasn't unplugged */ 274 if (!dev || !dev->present) 275 return -ENODEV; 276 277 dev_dbg(&dev->interface->dev, "minor %d, count = %zd\n", 278 dev->minor, count); 279 280 /* read count must be packet size (+ time stamp) */ 281 if ((count != dev->report_size) 282 && (count != (dev->report_size + 1))) 283 return -EINVAL; 284 285 /* repeat until no buffer overrun in callback handler occur */ 286 do { 287 atomic_set(&dev->overflow_flag, 0); 288 if ((read_idx = read_index(dev)) == -1) { 289 /* queue empty */ 290 if (file->f_flags & O_NONBLOCK) 291 return -EAGAIN; 292 else { 293 //next line will return when there is either new data, or the device is unplugged 294 int r = wait_event_interruptible(dev->read_wait, 295 (!dev->present 296 || (read_idx = 297 read_index 298 (dev)) != 299 -1)); 300 if (r) { 301 //we were interrupted by a signal 302 return -ERESTART; 303 } 304 if (!dev->present) { 305 //The device was unplugged 306 return -ENODEV; 307 } 308 if (read_idx == -1) { 309 // Can this happen ??? 310 return 0; 311 } 312 } 313 } 314 315 offset = read_idx * (dev->report_size + 1); 316 if (copy_to_user(buffer, dev->read_queue + offset, count)) { 317 return -EFAULT; 318 } 319 } while (atomic_read(&dev->overflow_flag)); 320 321 read_idx = ++read_idx == MAX_INTERRUPT_BUFFER ? 0 : read_idx; 322 atomic_set(&dev->read_idx, read_idx); 323 return count; 324 } 325 326 /* 327 * iowarrior_write 328 */ 329 static ssize_t iowarrior_write(struct file *file, 330 const char __user *user_buffer, 331 size_t count, loff_t *ppos) 332 { 333 struct iowarrior *dev; 334 int retval = 0; 335 char *buf = NULL; /* for IOW24 and IOW56 we need a buffer */ 336 struct urb *int_out_urb = NULL; 337 338 dev = file->private_data; 339 340 mutex_lock(&dev->mutex); 341 /* verify that the device wasn't unplugged */ 342 if (!dev->present) { 343 retval = -ENODEV; 344 goto exit; 345 } 346 dev_dbg(&dev->interface->dev, "minor %d, count = %zd\n", 347 dev->minor, count); 348 /* if count is 0 we're already done */ 349 if (count == 0) { 350 retval = 0; 351 goto exit; 352 } 353 /* We only accept full reports */ 354 if (count != dev->report_size) { 355 retval = -EINVAL; 356 goto exit; 357 } 358 switch (dev->product_id) { 359 case USB_DEVICE_ID_CODEMERCS_IOW24: 360 case USB_DEVICE_ID_CODEMERCS_IOWPV1: 361 case USB_DEVICE_ID_CODEMERCS_IOWPV2: 362 case USB_DEVICE_ID_CODEMERCS_IOW40: 363 /* IOW24 and IOW40 use a synchronous call */ 364 buf = memdup_user(user_buffer, count); 365 if (IS_ERR(buf)) { 366 retval = PTR_ERR(buf); 367 goto exit; 368 } 369 retval = usb_set_report(dev->interface, 2, 0, buf, count); 370 kfree(buf); 371 goto exit; 372 break; 373 case USB_DEVICE_ID_CODEMERCS_IOW56: 374 /* The IOW56 uses asynchronous IO and more urbs */ 375 if (atomic_read(&dev->write_busy) == MAX_WRITES_IN_FLIGHT) { 376 /* Wait until we are below the limit for submitted urbs */ 377 if (file->f_flags & O_NONBLOCK) { 378 retval = -EAGAIN; 379 goto exit; 380 } else { 381 retval = wait_event_interruptible(dev->write_wait, 382 (!dev->present || (atomic_read (&dev-> write_busy) < MAX_WRITES_IN_FLIGHT))); 383 if (retval) { 384 /* we were interrupted by a signal */ 385 retval = -ERESTART; 386 goto exit; 387 } 388 if (!dev->present) { 389 /* The device was unplugged */ 390 retval = -ENODEV; 391 goto exit; 392 } 393 if (!dev->opened) { 394 /* We were closed while waiting for an URB */ 395 retval = -ENODEV; 396 goto exit; 397 } 398 } 399 } 400 atomic_inc(&dev->write_busy); 401 int_out_urb = usb_alloc_urb(0, GFP_KERNEL); 402 if (!int_out_urb) { 403 retval = -ENOMEM; 404 goto error_no_urb; 405 } 406 buf = usb_alloc_coherent(dev->udev, dev->report_size, 407 GFP_KERNEL, &int_out_urb->transfer_dma); 408 if (!buf) { 409 retval = -ENOMEM; 410 dev_dbg(&dev->interface->dev, 411 "Unable to allocate buffer\n"); 412 goto error_no_buffer; 413 } 414 usb_fill_int_urb(int_out_urb, dev->udev, 415 usb_sndintpipe(dev->udev, 416 dev->int_out_endpoint->bEndpointAddress), 417 buf, dev->report_size, 418 iowarrior_write_callback, dev, 419 dev->int_out_endpoint->bInterval); 420 int_out_urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP; 421 if (copy_from_user(buf, user_buffer, count)) { 422 retval = -EFAULT; 423 goto error; 424 } 425 usb_anchor_urb(int_out_urb, &dev->submitted); 426 retval = usb_submit_urb(int_out_urb, GFP_KERNEL); 427 if (retval) { 428 dev_dbg(&dev->interface->dev, 429 "submit error %d for urb nr.%d\n", 430 retval, atomic_read(&dev->write_busy)); 431 usb_unanchor_urb(int_out_urb); 432 goto error; 433 } 434 /* submit was ok */ 435 retval = count; 436 usb_free_urb(int_out_urb); 437 goto exit; 438 break; 439 default: 440 /* what do we have here ? An unsupported Product-ID ? */ 441 dev_err(&dev->interface->dev, "%s - not supported for product=0x%x\n", 442 __func__, dev->product_id); 443 retval = -EFAULT; 444 goto exit; 445 break; 446 } 447 error: 448 usb_free_coherent(dev->udev, dev->report_size, buf, 449 int_out_urb->transfer_dma); 450 error_no_buffer: 451 usb_free_urb(int_out_urb); 452 error_no_urb: 453 atomic_dec(&dev->write_busy); 454 wake_up_interruptible(&dev->write_wait); 455 exit: 456 mutex_unlock(&dev->mutex); 457 return retval; 458 } 459 460 /** 461 * iowarrior_ioctl 462 */ 463 static long iowarrior_ioctl(struct file *file, unsigned int cmd, 464 unsigned long arg) 465 { 466 struct iowarrior *dev = NULL; 467 __u8 *buffer; 468 __u8 __user *user_buffer; 469 int retval; 470 int io_res; /* checks for bytes read/written and copy_to/from_user results */ 471 472 dev = file->private_data; 473 if (!dev) 474 return -ENODEV; 475 476 buffer = kzalloc(dev->report_size, GFP_KERNEL); 477 if (!buffer) 478 return -ENOMEM; 479 480 mutex_lock(&dev->mutex); 481 482 /* verify that the device wasn't unplugged */ 483 if (!dev->present) { 484 retval = -ENODEV; 485 goto error_out; 486 } 487 488 dev_dbg(&dev->interface->dev, "minor %d, cmd 0x%.4x, arg %ld\n", 489 dev->minor, cmd, arg); 490 491 retval = 0; 492 io_res = 0; 493 switch (cmd) { 494 case IOW_WRITE: 495 if (dev->product_id == USB_DEVICE_ID_CODEMERCS_IOW24 || 496 dev->product_id == USB_DEVICE_ID_CODEMERCS_IOWPV1 || 497 dev->product_id == USB_DEVICE_ID_CODEMERCS_IOWPV2 || 498 dev->product_id == USB_DEVICE_ID_CODEMERCS_IOW40) { 499 user_buffer = (__u8 __user *)arg; 500 io_res = copy_from_user(buffer, user_buffer, 501 dev->report_size); 502 if (io_res) { 503 retval = -EFAULT; 504 } else { 505 io_res = usb_set_report(dev->interface, 2, 0, 506 buffer, 507 dev->report_size); 508 if (io_res < 0) 509 retval = io_res; 510 } 511 } else { 512 retval = -EINVAL; 513 dev_err(&dev->interface->dev, 514 "ioctl 'IOW_WRITE' is not supported for product=0x%x.\n", 515 dev->product_id); 516 } 517 break; 518 case IOW_READ: 519 user_buffer = (__u8 __user *)arg; 520 io_res = usb_get_report(dev->udev, 521 dev->interface->cur_altsetting, 1, 0, 522 buffer, dev->report_size); 523 if (io_res < 0) 524 retval = io_res; 525 else { 526 io_res = copy_to_user(user_buffer, buffer, dev->report_size); 527 if (io_res) 528 retval = -EFAULT; 529 } 530 break; 531 case IOW_GETINFO: 532 { 533 /* Report available information for the device */ 534 struct iowarrior_info info; 535 /* needed for power consumption */ 536 struct usb_config_descriptor *cfg_descriptor = &dev->udev->actconfig->desc; 537 538 memset(&info, 0, sizeof(info)); 539 /* directly from the descriptor */ 540 info.vendor = le16_to_cpu(dev->udev->descriptor.idVendor); 541 info.product = dev->product_id; 542 info.revision = le16_to_cpu(dev->udev->descriptor.bcdDevice); 543 544 /* 0==UNKNOWN, 1==LOW(usb1.1) ,2=FULL(usb1.1), 3=HIGH(usb2.0) */ 545 info.speed = dev->udev->speed; 546 info.if_num = dev->interface->cur_altsetting->desc.bInterfaceNumber; 547 info.report_size = dev->report_size; 548 549 /* serial number string has been read earlier 8 chars or empty string */ 550 memcpy(info.serial, dev->chip_serial, 551 sizeof(dev->chip_serial)); 552 if (cfg_descriptor == NULL) { 553 info.power = -1; /* no information available */ 554 } else { 555 /* the MaxPower is stored in units of 2mA to make it fit into a byte-value */ 556 info.power = cfg_descriptor->bMaxPower * 2; 557 } 558 io_res = copy_to_user((struct iowarrior_info __user *)arg, &info, 559 sizeof(struct iowarrior_info)); 560 if (io_res) 561 retval = -EFAULT; 562 break; 563 } 564 default: 565 /* return that we did not understand this ioctl call */ 566 retval = -ENOTTY; 567 break; 568 } 569 error_out: 570 /* unlock the device */ 571 mutex_unlock(&dev->mutex); 572 kfree(buffer); 573 return retval; 574 } 575 576 /** 577 * iowarrior_open 578 */ 579 static int iowarrior_open(struct inode *inode, struct file *file) 580 { 581 struct iowarrior *dev = NULL; 582 struct usb_interface *interface; 583 int subminor; 584 int retval = 0; 585 586 subminor = iminor(inode); 587 588 interface = usb_find_interface(&iowarrior_driver, subminor); 589 if (!interface) { 590 pr_err("%s - error, can't find device for minor %d\n", 591 __func__, subminor); 592 return -ENODEV; 593 } 594 595 dev = usb_get_intfdata(interface); 596 if (!dev) 597 return -ENODEV; 598 599 mutex_lock(&dev->mutex); 600 601 /* Only one process can open each device, no sharing. */ 602 if (dev->opened) { 603 retval = -EBUSY; 604 goto out; 605 } 606 607 /* setup interrupt handler for receiving values */ 608 if ((retval = usb_submit_urb(dev->int_in_urb, GFP_KERNEL)) < 0) { 609 dev_err(&interface->dev, "Error %d while submitting URB\n", retval); 610 retval = -EFAULT; 611 goto out; 612 } 613 /* increment our usage count for the driver */ 614 ++dev->opened; 615 /* save our object in the file's private structure */ 616 file->private_data = dev; 617 retval = 0; 618 619 out: 620 mutex_unlock(&dev->mutex); 621 return retval; 622 } 623 624 /** 625 * iowarrior_release 626 */ 627 static int iowarrior_release(struct inode *inode, struct file *file) 628 { 629 struct iowarrior *dev; 630 int retval = 0; 631 632 dev = file->private_data; 633 if (!dev) 634 return -ENODEV; 635 636 dev_dbg(&dev->interface->dev, "minor %d\n", dev->minor); 637 638 /* lock our device */ 639 mutex_lock(&dev->mutex); 640 641 if (dev->opened <= 0) { 642 retval = -ENODEV; /* close called more than once */ 643 mutex_unlock(&dev->mutex); 644 } else { 645 dev->opened = 0; /* we're closing now */ 646 retval = 0; 647 if (dev->present) { 648 /* 649 The device is still connected so we only shutdown 650 pending read-/write-ops. 651 */ 652 usb_kill_urb(dev->int_in_urb); 653 wake_up_interruptible(&dev->read_wait); 654 wake_up_interruptible(&dev->write_wait); 655 mutex_unlock(&dev->mutex); 656 } else { 657 /* The device was unplugged, cleanup resources */ 658 mutex_unlock(&dev->mutex); 659 iowarrior_delete(dev); 660 } 661 } 662 return retval; 663 } 664 665 static __poll_t iowarrior_poll(struct file *file, poll_table * wait) 666 { 667 struct iowarrior *dev = file->private_data; 668 __poll_t mask = 0; 669 670 if (!dev->present) 671 return EPOLLERR | EPOLLHUP; 672 673 poll_wait(file, &dev->read_wait, wait); 674 poll_wait(file, &dev->write_wait, wait); 675 676 if (!dev->present) 677 return EPOLLERR | EPOLLHUP; 678 679 if (read_index(dev) != -1) 680 mask |= EPOLLIN | EPOLLRDNORM; 681 682 if (atomic_read(&dev->write_busy) < MAX_WRITES_IN_FLIGHT) 683 mask |= EPOLLOUT | EPOLLWRNORM; 684 return mask; 685 } 686 687 /* 688 * File operations needed when we register this driver. 689 * This assumes that this driver NEEDS file operations, 690 * of course, which means that the driver is expected 691 * to have a node in the /dev directory. If the USB 692 * device were for a network interface then the driver 693 * would use "struct net_driver" instead, and a serial 694 * device would use "struct tty_driver". 695 */ 696 static const struct file_operations iowarrior_fops = { 697 .owner = THIS_MODULE, 698 .write = iowarrior_write, 699 .read = iowarrior_read, 700 .unlocked_ioctl = iowarrior_ioctl, 701 .open = iowarrior_open, 702 .release = iowarrior_release, 703 .poll = iowarrior_poll, 704 .llseek = noop_llseek, 705 }; 706 707 static char *iowarrior_devnode(struct device *dev, umode_t *mode) 708 { 709 return kasprintf(GFP_KERNEL, "usb/%s", dev_name(dev)); 710 } 711 712 /* 713 * usb class driver info in order to get a minor number from the usb core, 714 * and to have the device registered with devfs and the driver core 715 */ 716 static struct usb_class_driver iowarrior_class = { 717 .name = "iowarrior%d", 718 .devnode = iowarrior_devnode, 719 .fops = &iowarrior_fops, 720 .minor_base = IOWARRIOR_MINOR_BASE, 721 }; 722 723 /*---------------------------------*/ 724 /* probe and disconnect functions */ 725 /*---------------------------------*/ 726 /** 727 * iowarrior_probe 728 * 729 * Called by the usb core when a new device is connected that it thinks 730 * this driver might be interested in. 731 */ 732 static int iowarrior_probe(struct usb_interface *interface, 733 const struct usb_device_id *id) 734 { 735 struct usb_device *udev = interface_to_usbdev(interface); 736 struct iowarrior *dev = NULL; 737 struct usb_host_interface *iface_desc; 738 int retval = -ENOMEM; 739 int res; 740 741 /* allocate memory for our device state and initialize it */ 742 dev = kzalloc(sizeof(struct iowarrior), GFP_KERNEL); 743 if (!dev) 744 return retval; 745 746 mutex_init(&dev->mutex); 747 748 atomic_set(&dev->intr_idx, 0); 749 atomic_set(&dev->read_idx, 0); 750 atomic_set(&dev->overflow_flag, 0); 751 init_waitqueue_head(&dev->read_wait); 752 atomic_set(&dev->write_busy, 0); 753 init_waitqueue_head(&dev->write_wait); 754 755 dev->udev = udev; 756 dev->interface = usb_get_intf(interface); 757 758 iface_desc = interface->cur_altsetting; 759 dev->product_id = le16_to_cpu(udev->descriptor.idProduct); 760 761 init_usb_anchor(&dev->submitted); 762 763 res = usb_find_last_int_in_endpoint(iface_desc, &dev->int_in_endpoint); 764 if (res) { 765 dev_err(&interface->dev, "no interrupt-in endpoint found\n"); 766 retval = res; 767 goto error; 768 } 769 770 if (dev->product_id == USB_DEVICE_ID_CODEMERCS_IOW56) { 771 res = usb_find_last_int_out_endpoint(iface_desc, 772 &dev->int_out_endpoint); 773 if (res) { 774 dev_err(&interface->dev, "no interrupt-out endpoint found\n"); 775 retval = res; 776 goto error; 777 } 778 } 779 780 /* we have to check the report_size often, so remember it in the endianness suitable for our machine */ 781 dev->report_size = usb_endpoint_maxp(dev->int_in_endpoint); 782 if ((dev->interface->cur_altsetting->desc.bInterfaceNumber == 0) && 783 (dev->product_id == USB_DEVICE_ID_CODEMERCS_IOW56)) 784 /* IOWarrior56 has wMaxPacketSize different from report size */ 785 dev->report_size = 7; 786 787 /* create the urb and buffer for reading */ 788 dev->int_in_urb = usb_alloc_urb(0, GFP_KERNEL); 789 if (!dev->int_in_urb) 790 goto error; 791 dev->int_in_buffer = kmalloc(dev->report_size, GFP_KERNEL); 792 if (!dev->int_in_buffer) 793 goto error; 794 usb_fill_int_urb(dev->int_in_urb, dev->udev, 795 usb_rcvintpipe(dev->udev, 796 dev->int_in_endpoint->bEndpointAddress), 797 dev->int_in_buffer, dev->report_size, 798 iowarrior_callback, dev, 799 dev->int_in_endpoint->bInterval); 800 /* create an internal buffer for interrupt data from the device */ 801 dev->read_queue = 802 kmalloc_array(dev->report_size + 1, MAX_INTERRUPT_BUFFER, 803 GFP_KERNEL); 804 if (!dev->read_queue) 805 goto error; 806 /* Get the serial-number of the chip */ 807 memset(dev->chip_serial, 0x00, sizeof(dev->chip_serial)); 808 usb_string(udev, udev->descriptor.iSerialNumber, dev->chip_serial, 809 sizeof(dev->chip_serial)); 810 if (strlen(dev->chip_serial) != 8) 811 memset(dev->chip_serial, 0x00, sizeof(dev->chip_serial)); 812 813 /* Set the idle timeout to 0, if this is interface 0 */ 814 if (dev->interface->cur_altsetting->desc.bInterfaceNumber == 0) { 815 usb_control_msg(udev, usb_sndctrlpipe(udev, 0), 816 0x0A, 817 USB_TYPE_CLASS | USB_RECIP_INTERFACE, 0, 818 0, NULL, 0, USB_CTRL_SET_TIMEOUT); 819 } 820 /* allow device read and ioctl */ 821 dev->present = 1; 822 823 /* we can register the device now, as it is ready */ 824 usb_set_intfdata(interface, dev); 825 826 retval = usb_register_dev(interface, &iowarrior_class); 827 if (retval) { 828 /* something prevented us from registering this driver */ 829 dev_err(&interface->dev, "Not able to get a minor for this device.\n"); 830 goto error; 831 } 832 833 dev->minor = interface->minor; 834 835 /* let the user know what node this device is now attached to */ 836 dev_info(&interface->dev, "IOWarrior product=0x%x, serial=%s interface=%d " 837 "now attached to iowarrior%d\n", dev->product_id, dev->chip_serial, 838 iface_desc->desc.bInterfaceNumber, dev->minor - IOWARRIOR_MINOR_BASE); 839 return retval; 840 841 error: 842 iowarrior_delete(dev); 843 return retval; 844 } 845 846 /** 847 * iowarrior_disconnect 848 * 849 * Called by the usb core when the device is removed from the system. 850 */ 851 static void iowarrior_disconnect(struct usb_interface *interface) 852 { 853 struct iowarrior *dev = usb_get_intfdata(interface); 854 int minor = dev->minor; 855 856 usb_deregister_dev(interface, &iowarrior_class); 857 858 mutex_lock(&dev->mutex); 859 860 /* prevent device read, write and ioctl */ 861 dev->present = 0; 862 863 if (dev->opened) { 864 /* There is a process that holds a filedescriptor to the device , 865 so we only shutdown read-/write-ops going on. 866 Deleting the device is postponed until close() was called. 867 */ 868 usb_kill_urb(dev->int_in_urb); 869 usb_kill_anchored_urbs(&dev->submitted); 870 wake_up_interruptible(&dev->read_wait); 871 wake_up_interruptible(&dev->write_wait); 872 mutex_unlock(&dev->mutex); 873 } else { 874 /* no process is using the device, cleanup now */ 875 mutex_unlock(&dev->mutex); 876 iowarrior_delete(dev); 877 } 878 879 dev_info(&interface->dev, "I/O-Warror #%d now disconnected\n", 880 minor - IOWARRIOR_MINOR_BASE); 881 } 882 883 /* usb specific object needed to register this driver with the usb subsystem */ 884 static struct usb_driver iowarrior_driver = { 885 .name = "iowarrior", 886 .probe = iowarrior_probe, 887 .disconnect = iowarrior_disconnect, 888 .id_table = iowarrior_ids, 889 }; 890 891 module_usb_driver(iowarrior_driver); 892