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