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