1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Native support for the I/O-Warrior USB devices 4 * 5 * Copyright (c) 2003-2005, 2020 Code Mercenaries GmbH 6 * written by Christian Lucht <lucht@codemercs.com> and 7 * Christoph Jung <jung@codemercs.com> 8 * 9 * based on 10 11 * usb-skeleton.c by Greg Kroah-Hartman <greg@kroah.com> 12 * brlvger.c by Stephane Dalton <sdalton@videotron.ca> 13 * and Stephane Doyon <s.doyon@videotron.ca> 14 * 15 * Released under the GPLv2. 16 */ 17 18 #include <linux/module.h> 19 #include <linux/usb.h> 20 #include <linux/slab.h> 21 #include <linux/sched.h> 22 #include <linux/mutex.h> 23 #include <linux/poll.h> 24 #include <linux/usb/iowarrior.h> 25 26 #define DRIVER_AUTHOR "Christian Lucht <lucht@codemercs.com>" 27 #define DRIVER_DESC "USB IO-Warrior driver" 28 29 #define USB_VENDOR_ID_CODEMERCS 1984 30 /* low speed iowarrior */ 31 #define USB_DEVICE_ID_CODEMERCS_IOW40 0x1500 32 #define USB_DEVICE_ID_CODEMERCS_IOW24 0x1501 33 #define USB_DEVICE_ID_CODEMERCS_IOWPV1 0x1511 34 #define USB_DEVICE_ID_CODEMERCS_IOWPV2 0x1512 35 /* full speed iowarrior */ 36 #define USB_DEVICE_ID_CODEMERCS_IOW56 0x1503 37 /* fuller speed iowarrior */ 38 #define USB_DEVICE_ID_CODEMERCS_IOW28 0x1504 39 #define USB_DEVICE_ID_CODEMERCS_IOW28L 0x1505 40 #define USB_DEVICE_ID_CODEMERCS_IOW100 0x1506 41 42 /* OEMed devices */ 43 #define USB_DEVICE_ID_CODEMERCS_IOW24SAG 0x158a 44 #define USB_DEVICE_ID_CODEMERCS_IOW56AM 0x158b 45 46 /* Get a minor range for your devices from the usb maintainer */ 47 #ifdef CONFIG_USB_DYNAMIC_MINORS 48 #define IOWARRIOR_MINOR_BASE 0 49 #else 50 #define IOWARRIOR_MINOR_BASE 208 // SKELETON_MINOR_BASE 192 + 16, not official yet 51 #endif 52 53 /* interrupt input queue size */ 54 #define MAX_INTERRUPT_BUFFER 16 55 /* 56 maximum number of urbs that are submitted for writes at the same time, 57 this applies to the IOWarrior56 only! 58 IOWarrior24 and IOWarrior40 use synchronous usb_control_msg calls. 59 */ 60 #define MAX_WRITES_IN_FLIGHT 4 61 62 MODULE_AUTHOR(DRIVER_AUTHOR); 63 MODULE_DESCRIPTION(DRIVER_DESC); 64 MODULE_LICENSE("GPL"); 65 66 static struct usb_driver iowarrior_driver; 67 68 /*--------------*/ 69 /* data */ 70 /*--------------*/ 71 72 /* Structure to hold all of our device specific stuff */ 73 struct iowarrior { 74 struct mutex mutex; /* locks this structure */ 75 struct usb_device *udev; /* save off the usb device pointer */ 76 struct usb_interface *interface; /* the interface for this device */ 77 unsigned char minor; /* the starting minor number for this device */ 78 struct usb_endpoint_descriptor *int_out_endpoint; /* endpoint for reading (needed for IOW56 only) */ 79 struct usb_endpoint_descriptor *int_in_endpoint; /* endpoint for reading */ 80 struct urb *int_in_urb; /* the urb for reading data */ 81 unsigned char *int_in_buffer; /* buffer for data to be read */ 82 unsigned char serial_number; /* to detect lost packages */ 83 unsigned char *read_queue; /* size is MAX_INTERRUPT_BUFFER * packet size */ 84 wait_queue_head_t read_wait; 85 wait_queue_head_t write_wait; /* wait-queue for writing to the device */ 86 atomic_t write_busy; /* number of write-urbs submitted */ 87 atomic_t read_idx; 88 atomic_t intr_idx; 89 atomic_t overflow_flag; /* signals an index 'rollover' */ 90 int present; /* this is 1 as long as the device is connected */ 91 int opened; /* this is 1 if the device is currently open */ 92 char chip_serial[9]; /* the serial number string of the chip connected */ 93 int report_size; /* number of bytes in a report */ 94 u16 product_id; 95 struct usb_anchor submitted; 96 }; 97 98 /*--------------*/ 99 /* globals */ 100 /*--------------*/ 101 102 /* 103 * USB spec identifies 5 second timeouts. 104 */ 105 #define GET_TIMEOUT 5 106 #define USB_REQ_GET_REPORT 0x01 107 //#if 0 108 static int usb_get_report(struct usb_device *dev, 109 struct usb_host_interface *inter, unsigned char type, 110 unsigned char id, void *buf, int size) 111 { 112 return usb_control_msg(dev, usb_rcvctrlpipe(dev, 0), 113 USB_REQ_GET_REPORT, 114 USB_DIR_IN | USB_TYPE_CLASS | 115 USB_RECIP_INTERFACE, (type << 8) + id, 116 inter->desc.bInterfaceNumber, buf, size, 117 GET_TIMEOUT*HZ); 118 } 119 //#endif 120 121 #define USB_REQ_SET_REPORT 0x09 122 123 static int usb_set_report(struct usb_interface *intf, unsigned char type, 124 unsigned char id, void *buf, int size) 125 { 126 return usb_control_msg(interface_to_usbdev(intf), 127 usb_sndctrlpipe(interface_to_usbdev(intf), 0), 128 USB_REQ_SET_REPORT, 129 USB_TYPE_CLASS | USB_RECIP_INTERFACE, 130 (type << 8) + id, 131 intf->cur_altsetting->desc.bInterfaceNumber, buf, 132 size, HZ); 133 } 134 135 /*---------------------*/ 136 /* driver registration */ 137 /*---------------------*/ 138 /* table of devices that work with this driver */ 139 static const struct usb_device_id iowarrior_ids[] = { 140 {USB_DEVICE(USB_VENDOR_ID_CODEMERCS, USB_DEVICE_ID_CODEMERCS_IOW40)}, 141 {USB_DEVICE(USB_VENDOR_ID_CODEMERCS, USB_DEVICE_ID_CODEMERCS_IOW24)}, 142 {USB_DEVICE(USB_VENDOR_ID_CODEMERCS, USB_DEVICE_ID_CODEMERCS_IOWPV1)}, 143 {USB_DEVICE(USB_VENDOR_ID_CODEMERCS, USB_DEVICE_ID_CODEMERCS_IOWPV2)}, 144 {USB_DEVICE(USB_VENDOR_ID_CODEMERCS, USB_DEVICE_ID_CODEMERCS_IOW56)}, 145 {USB_DEVICE(USB_VENDOR_ID_CODEMERCS, USB_DEVICE_ID_CODEMERCS_IOW24SAG)}, 146 {USB_DEVICE(USB_VENDOR_ID_CODEMERCS, USB_DEVICE_ID_CODEMERCS_IOW56AM)}, 147 {USB_DEVICE(USB_VENDOR_ID_CODEMERCS, USB_DEVICE_ID_CODEMERCS_IOW28)}, 148 {USB_DEVICE(USB_VENDOR_ID_CODEMERCS, USB_DEVICE_ID_CODEMERCS_IOW28L)}, 149 {USB_DEVICE(USB_VENDOR_ID_CODEMERCS, USB_DEVICE_ID_CODEMERCS_IOW100)}, 150 {} /* Terminating entry */ 151 }; 152 MODULE_DEVICE_TABLE(usb, iowarrior_ids); 153 154 /* 155 * USB callback handler for reading data 156 */ 157 static void iowarrior_callback(struct urb *urb) 158 { 159 struct iowarrior *dev = urb->context; 160 int intr_idx; 161 int read_idx; 162 int aux_idx; 163 int offset; 164 int status = urb->status; 165 int retval; 166 167 switch (status) { 168 case 0: 169 /* success */ 170 break; 171 case -ECONNRESET: 172 case -ENOENT: 173 case -ESHUTDOWN: 174 return; 175 default: 176 goto exit; 177 } 178 179 intr_idx = atomic_read(&dev->intr_idx); 180 /* aux_idx become previous intr_idx */ 181 aux_idx = (intr_idx == 0) ? (MAX_INTERRUPT_BUFFER - 1) : (intr_idx - 1); 182 read_idx = atomic_read(&dev->read_idx); 183 184 /* queue is not empty and it's interface 0 */ 185 if ((intr_idx != read_idx) 186 && (dev->interface->cur_altsetting->desc.bInterfaceNumber == 0)) { 187 /* + 1 for serial number */ 188 offset = aux_idx * (dev->report_size + 1); 189 if (!memcmp 190 (dev->read_queue + offset, urb->transfer_buffer, 191 dev->report_size)) { 192 /* equal values on interface 0 will be ignored */ 193 goto exit; 194 } 195 } 196 197 /* aux_idx become next intr_idx */ 198 aux_idx = (intr_idx == (MAX_INTERRUPT_BUFFER - 1)) ? 0 : (intr_idx + 1); 199 if (read_idx == aux_idx) { 200 /* queue full, dropping oldest input */ 201 read_idx = (++read_idx == MAX_INTERRUPT_BUFFER) ? 0 : read_idx; 202 atomic_set(&dev->read_idx, read_idx); 203 atomic_set(&dev->overflow_flag, 1); 204 } 205 206 /* +1 for serial number */ 207 offset = intr_idx * (dev->report_size + 1); 208 memcpy(dev->read_queue + offset, urb->transfer_buffer, 209 dev->report_size); 210 *(dev->read_queue + offset + (dev->report_size)) = dev->serial_number++; 211 212 atomic_set(&dev->intr_idx, aux_idx); 213 /* tell the blocking read about the new data */ 214 wake_up_interruptible(&dev->read_wait); 215 216 exit: 217 retval = usb_submit_urb(urb, GFP_ATOMIC); 218 if (retval) 219 dev_err(&dev->interface->dev, "%s - usb_submit_urb failed with result %d\n", 220 __func__, retval); 221 222 } 223 224 /* 225 * USB Callback handler for write-ops 226 */ 227 static void iowarrior_write_callback(struct urb *urb) 228 { 229 struct iowarrior *dev; 230 int status = urb->status; 231 232 dev = urb->context; 233 /* sync/async unlink faults aren't errors */ 234 if (status && 235 !(status == -ENOENT || 236 status == -ECONNRESET || status == -ESHUTDOWN)) { 237 dev_dbg(&dev->interface->dev, 238 "nonzero write bulk status received: %d\n", status); 239 } 240 /* free up our allocated buffer */ 241 usb_free_coherent(urb->dev, urb->transfer_buffer_length, 242 urb->transfer_buffer, urb->transfer_dma); 243 /* tell a waiting writer the interrupt-out-pipe is available again */ 244 atomic_dec(&dev->write_busy); 245 wake_up_interruptible(&dev->write_wait); 246 } 247 248 /* 249 * iowarrior_delete 250 */ 251 static inline void iowarrior_delete(struct iowarrior *dev) 252 { 253 dev_dbg(&dev->interface->dev, "minor %d\n", dev->minor); 254 kfree(dev->int_in_buffer); 255 usb_free_urb(dev->int_in_urb); 256 kfree(dev->read_queue); 257 usb_put_intf(dev->interface); 258 kfree(dev); 259 } 260 261 /*---------------------*/ 262 /* fops implementation */ 263 /*---------------------*/ 264 265 static int read_index(struct iowarrior *dev) 266 { 267 int intr_idx, read_idx; 268 269 read_idx = atomic_read(&dev->read_idx); 270 intr_idx = atomic_read(&dev->intr_idx); 271 272 return (read_idx == intr_idx ? -1 : read_idx); 273 } 274 275 /* 276 * iowarrior_read 277 */ 278 static ssize_t iowarrior_read(struct file *file, char __user *buffer, 279 size_t count, loff_t *ppos) 280 { 281 struct iowarrior *dev; 282 int read_idx; 283 int offset; 284 285 dev = file->private_data; 286 287 /* verify that the device wasn't unplugged */ 288 if (!dev || !dev->present) 289 return -ENODEV; 290 291 dev_dbg(&dev->interface->dev, "minor %d, count = %zd\n", 292 dev->minor, count); 293 294 /* read count must be packet size (+ time stamp) */ 295 if ((count != dev->report_size) 296 && (count != (dev->report_size + 1))) 297 return -EINVAL; 298 299 /* repeat until no buffer overrun in callback handler occur */ 300 do { 301 atomic_set(&dev->overflow_flag, 0); 302 if ((read_idx = read_index(dev)) == -1) { 303 /* queue empty */ 304 if (file->f_flags & O_NONBLOCK) 305 return -EAGAIN; 306 else { 307 //next line will return when there is either new data, or the device is unplugged 308 int r = wait_event_interruptible(dev->read_wait, 309 (!dev->present 310 || (read_idx = 311 read_index 312 (dev)) != 313 -1)); 314 if (r) { 315 //we were interrupted by a signal 316 return -ERESTART; 317 } 318 if (!dev->present) { 319 //The device was unplugged 320 return -ENODEV; 321 } 322 if (read_idx == -1) { 323 // Can this happen ??? 324 return 0; 325 } 326 } 327 } 328 329 offset = read_idx * (dev->report_size + 1); 330 if (copy_to_user(buffer, dev->read_queue + offset, count)) { 331 return -EFAULT; 332 } 333 } while (atomic_read(&dev->overflow_flag)); 334 335 read_idx = ++read_idx == MAX_INTERRUPT_BUFFER ? 0 : read_idx; 336 atomic_set(&dev->read_idx, read_idx); 337 return count; 338 } 339 340 /* 341 * iowarrior_write 342 */ 343 static ssize_t iowarrior_write(struct file *file, 344 const char __user *user_buffer, 345 size_t count, loff_t *ppos) 346 { 347 struct iowarrior *dev; 348 int retval = 0; 349 char *buf = NULL; /* for IOW24 and IOW56 we need a buffer */ 350 struct urb *int_out_urb = NULL; 351 352 dev = file->private_data; 353 354 mutex_lock(&dev->mutex); 355 /* verify that the device wasn't unplugged */ 356 if (!dev->present) { 357 retval = -ENODEV; 358 goto exit; 359 } 360 dev_dbg(&dev->interface->dev, "minor %d, count = %zd\n", 361 dev->minor, count); 362 /* if count is 0 we're already done */ 363 if (count == 0) { 364 retval = 0; 365 goto exit; 366 } 367 /* We only accept full reports */ 368 if (count != dev->report_size) { 369 retval = -EINVAL; 370 goto exit; 371 } 372 switch (dev->product_id) { 373 case USB_DEVICE_ID_CODEMERCS_IOW24: 374 case USB_DEVICE_ID_CODEMERCS_IOW24SAG: 375 case USB_DEVICE_ID_CODEMERCS_IOWPV1: 376 case USB_DEVICE_ID_CODEMERCS_IOWPV2: 377 case USB_DEVICE_ID_CODEMERCS_IOW40: 378 /* IOW24 and IOW40 use a synchronous call */ 379 buf = memdup_user(user_buffer, count); 380 if (IS_ERR(buf)) { 381 retval = PTR_ERR(buf); 382 goto exit; 383 } 384 retval = usb_set_report(dev->interface, 2, 0, buf, count); 385 kfree(buf); 386 goto exit; 387 break; 388 case USB_DEVICE_ID_CODEMERCS_IOW56: 389 case USB_DEVICE_ID_CODEMERCS_IOW56AM: 390 case USB_DEVICE_ID_CODEMERCS_IOW28: 391 case USB_DEVICE_ID_CODEMERCS_IOW28L: 392 case USB_DEVICE_ID_CODEMERCS_IOW100: 393 /* The IOW56 uses asynchronous IO and more urbs */ 394 if (atomic_read(&dev->write_busy) == MAX_WRITES_IN_FLIGHT) { 395 /* Wait until we are below the limit for submitted urbs */ 396 if (file->f_flags & O_NONBLOCK) { 397 retval = -EAGAIN; 398 goto exit; 399 } else { 400 retval = wait_event_interruptible(dev->write_wait, 401 (!dev->present || (atomic_read (&dev-> write_busy) < MAX_WRITES_IN_FLIGHT))); 402 if (retval) { 403 /* we were interrupted by a signal */ 404 retval = -ERESTART; 405 goto exit; 406 } 407 if (!dev->present) { 408 /* The device was unplugged */ 409 retval = -ENODEV; 410 goto exit; 411 } 412 if (!dev->opened) { 413 /* We were closed while waiting for an URB */ 414 retval = -ENODEV; 415 goto exit; 416 } 417 } 418 } 419 atomic_inc(&dev->write_busy); 420 int_out_urb = usb_alloc_urb(0, GFP_KERNEL); 421 if (!int_out_urb) { 422 retval = -ENOMEM; 423 goto error_no_urb; 424 } 425 buf = usb_alloc_coherent(dev->udev, dev->report_size, 426 GFP_KERNEL, &int_out_urb->transfer_dma); 427 if (!buf) { 428 retval = -ENOMEM; 429 dev_dbg(&dev->interface->dev, 430 "Unable to allocate buffer\n"); 431 goto error_no_buffer; 432 } 433 usb_fill_int_urb(int_out_urb, dev->udev, 434 usb_sndintpipe(dev->udev, 435 dev->int_out_endpoint->bEndpointAddress), 436 buf, dev->report_size, 437 iowarrior_write_callback, dev, 438 dev->int_out_endpoint->bInterval); 439 int_out_urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP; 440 if (copy_from_user(buf, user_buffer, count)) { 441 retval = -EFAULT; 442 goto error; 443 } 444 usb_anchor_urb(int_out_urb, &dev->submitted); 445 retval = usb_submit_urb(int_out_urb, GFP_KERNEL); 446 if (retval) { 447 dev_dbg(&dev->interface->dev, 448 "submit error %d for urb nr.%d\n", 449 retval, atomic_read(&dev->write_busy)); 450 usb_unanchor_urb(int_out_urb); 451 goto error; 452 } 453 /* submit was ok */ 454 retval = count; 455 usb_free_urb(int_out_urb); 456 goto exit; 457 break; 458 default: 459 /* what do we have here ? An unsupported Product-ID ? */ 460 dev_err(&dev->interface->dev, "%s - not supported for product=0x%x\n", 461 __func__, dev->product_id); 462 retval = -EFAULT; 463 goto exit; 464 break; 465 } 466 error: 467 usb_free_coherent(dev->udev, dev->report_size, buf, 468 int_out_urb->transfer_dma); 469 error_no_buffer: 470 usb_free_urb(int_out_urb); 471 error_no_urb: 472 atomic_dec(&dev->write_busy); 473 wake_up_interruptible(&dev->write_wait); 474 exit: 475 mutex_unlock(&dev->mutex); 476 return retval; 477 } 478 479 /* 480 * iowarrior_ioctl 481 */ 482 static long iowarrior_ioctl(struct file *file, unsigned int cmd, 483 unsigned long arg) 484 { 485 struct iowarrior *dev = NULL; 486 __u8 *buffer; 487 __u8 __user *user_buffer; 488 int retval; 489 int io_res; /* checks for bytes read/written and copy_to/from_user results */ 490 491 dev = file->private_data; 492 if (!dev) 493 return -ENODEV; 494 495 buffer = kzalloc(dev->report_size, GFP_KERNEL); 496 if (!buffer) 497 return -ENOMEM; 498 499 mutex_lock(&dev->mutex); 500 501 /* verify that the device wasn't unplugged */ 502 if (!dev->present) { 503 retval = -ENODEV; 504 goto error_out; 505 } 506 507 dev_dbg(&dev->interface->dev, "minor %d, cmd 0x%.4x, arg %ld\n", 508 dev->minor, cmd, arg); 509 510 retval = 0; 511 io_res = 0; 512 switch (cmd) { 513 case IOW_WRITE: 514 if (dev->product_id == USB_DEVICE_ID_CODEMERCS_IOW24 || 515 dev->product_id == USB_DEVICE_ID_CODEMERCS_IOW24SAG || 516 dev->product_id == USB_DEVICE_ID_CODEMERCS_IOWPV1 || 517 dev->product_id == USB_DEVICE_ID_CODEMERCS_IOWPV2 || 518 dev->product_id == USB_DEVICE_ID_CODEMERCS_IOW40) { 519 user_buffer = (__u8 __user *)arg; 520 io_res = copy_from_user(buffer, user_buffer, 521 dev->report_size); 522 if (io_res) { 523 retval = -EFAULT; 524 } else { 525 io_res = usb_set_report(dev->interface, 2, 0, 526 buffer, 527 dev->report_size); 528 if (io_res < 0) 529 retval = io_res; 530 } 531 } else { 532 retval = -EINVAL; 533 dev_err(&dev->interface->dev, 534 "ioctl 'IOW_WRITE' is not supported for product=0x%x.\n", 535 dev->product_id); 536 } 537 break; 538 case IOW_READ: 539 user_buffer = (__u8 __user *)arg; 540 io_res = usb_get_report(dev->udev, 541 dev->interface->cur_altsetting, 1, 0, 542 buffer, dev->report_size); 543 if (io_res < 0) 544 retval = io_res; 545 else { 546 io_res = copy_to_user(user_buffer, buffer, dev->report_size); 547 if (io_res) 548 retval = -EFAULT; 549 } 550 break; 551 case IOW_GETINFO: 552 { 553 /* Report available information for the device */ 554 struct iowarrior_info info; 555 /* needed for power consumption */ 556 struct usb_config_descriptor *cfg_descriptor = &dev->udev->actconfig->desc; 557 558 memset(&info, 0, sizeof(info)); 559 /* directly from the descriptor */ 560 info.vendor = le16_to_cpu(dev->udev->descriptor.idVendor); 561 info.product = dev->product_id; 562 info.revision = le16_to_cpu(dev->udev->descriptor.bcdDevice); 563 564 /* 0==UNKNOWN, 1==LOW(usb1.1) ,2=FULL(usb1.1), 3=HIGH(usb2.0) */ 565 info.speed = dev->udev->speed; 566 info.if_num = dev->interface->cur_altsetting->desc.bInterfaceNumber; 567 info.report_size = dev->report_size; 568 569 /* serial number string has been read earlier 8 chars or empty string */ 570 memcpy(info.serial, dev->chip_serial, 571 sizeof(dev->chip_serial)); 572 if (cfg_descriptor == NULL) { 573 info.power = -1; /* no information available */ 574 } else { 575 /* the MaxPower is stored in units of 2mA to make it fit into a byte-value */ 576 info.power = cfg_descriptor->bMaxPower * 2; 577 } 578 io_res = copy_to_user((struct iowarrior_info __user *)arg, &info, 579 sizeof(struct iowarrior_info)); 580 if (io_res) 581 retval = -EFAULT; 582 break; 583 } 584 default: 585 /* return that we did not understand this ioctl call */ 586 retval = -ENOTTY; 587 break; 588 } 589 error_out: 590 /* unlock the device */ 591 mutex_unlock(&dev->mutex); 592 kfree(buffer); 593 return retval; 594 } 595 596 /* 597 * iowarrior_open 598 */ 599 static int iowarrior_open(struct inode *inode, struct file *file) 600 { 601 struct iowarrior *dev = NULL; 602 struct usb_interface *interface; 603 int subminor; 604 int retval = 0; 605 606 subminor = iminor(inode); 607 608 interface = usb_find_interface(&iowarrior_driver, subminor); 609 if (!interface) { 610 pr_err("%s - error, can't find device for minor %d\n", 611 __func__, subminor); 612 return -ENODEV; 613 } 614 615 dev = usb_get_intfdata(interface); 616 if (!dev) 617 return -ENODEV; 618 619 mutex_lock(&dev->mutex); 620 621 /* Only one process can open each device, no sharing. */ 622 if (dev->opened) { 623 retval = -EBUSY; 624 goto out; 625 } 626 627 /* setup interrupt handler for receiving values */ 628 if ((retval = usb_submit_urb(dev->int_in_urb, GFP_KERNEL)) < 0) { 629 dev_err(&interface->dev, "Error %d while submitting URB\n", retval); 630 retval = -EFAULT; 631 goto out; 632 } 633 /* increment our usage count for the driver */ 634 ++dev->opened; 635 /* save our object in the file's private structure */ 636 file->private_data = dev; 637 retval = 0; 638 639 out: 640 mutex_unlock(&dev->mutex); 641 return retval; 642 } 643 644 /* 645 * iowarrior_release 646 */ 647 static int iowarrior_release(struct inode *inode, struct file *file) 648 { 649 struct iowarrior *dev; 650 int retval = 0; 651 652 dev = file->private_data; 653 if (!dev) 654 return -ENODEV; 655 656 dev_dbg(&dev->interface->dev, "minor %d\n", dev->minor); 657 658 /* lock our device */ 659 mutex_lock(&dev->mutex); 660 661 if (dev->opened <= 0) { 662 retval = -ENODEV; /* close called more than once */ 663 mutex_unlock(&dev->mutex); 664 } else { 665 dev->opened = 0; /* we're closing now */ 666 retval = 0; 667 if (dev->present) { 668 /* 669 The device is still connected so we only shutdown 670 pending read-/write-ops. 671 */ 672 usb_kill_urb(dev->int_in_urb); 673 wake_up_interruptible(&dev->read_wait); 674 wake_up_interruptible(&dev->write_wait); 675 mutex_unlock(&dev->mutex); 676 } else { 677 /* The device was unplugged, cleanup resources */ 678 mutex_unlock(&dev->mutex); 679 iowarrior_delete(dev); 680 } 681 } 682 return retval; 683 } 684 685 static __poll_t iowarrior_poll(struct file *file, poll_table * wait) 686 { 687 struct iowarrior *dev = file->private_data; 688 __poll_t mask = 0; 689 690 if (!dev->present) 691 return EPOLLERR | EPOLLHUP; 692 693 poll_wait(file, &dev->read_wait, wait); 694 poll_wait(file, &dev->write_wait, wait); 695 696 if (!dev->present) 697 return EPOLLERR | EPOLLHUP; 698 699 if (read_index(dev) != -1) 700 mask |= EPOLLIN | EPOLLRDNORM; 701 702 if (atomic_read(&dev->write_busy) < MAX_WRITES_IN_FLIGHT) 703 mask |= EPOLLOUT | EPOLLWRNORM; 704 return mask; 705 } 706 707 /* 708 * File operations needed when we register this driver. 709 * This assumes that this driver NEEDS file operations, 710 * of course, which means that the driver is expected 711 * to have a node in the /dev directory. If the USB 712 * device were for a network interface then the driver 713 * would use "struct net_driver" instead, and a serial 714 * device would use "struct tty_driver". 715 */ 716 static const struct file_operations iowarrior_fops = { 717 .owner = THIS_MODULE, 718 .write = iowarrior_write, 719 .read = iowarrior_read, 720 .unlocked_ioctl = iowarrior_ioctl, 721 .open = iowarrior_open, 722 .release = iowarrior_release, 723 .poll = iowarrior_poll, 724 .llseek = noop_llseek, 725 }; 726 727 static char *iowarrior_devnode(struct device *dev, umode_t *mode) 728 { 729 return kasprintf(GFP_KERNEL, "usb/%s", dev_name(dev)); 730 } 731 732 /* 733 * usb class driver info in order to get a minor number from the usb core, 734 * and to have the device registered with devfs and the driver core 735 */ 736 static struct usb_class_driver iowarrior_class = { 737 .name = "iowarrior%d", 738 .devnode = iowarrior_devnode, 739 .fops = &iowarrior_fops, 740 .minor_base = IOWARRIOR_MINOR_BASE, 741 }; 742 743 /*---------------------------------*/ 744 /* probe and disconnect functions */ 745 /*---------------------------------*/ 746 /* 747 * iowarrior_probe 748 * 749 * Called by the usb core when a new device is connected that it thinks 750 * this driver might be interested in. 751 */ 752 static int iowarrior_probe(struct usb_interface *interface, 753 const struct usb_device_id *id) 754 { 755 struct usb_device *udev = interface_to_usbdev(interface); 756 struct iowarrior *dev = NULL; 757 struct usb_host_interface *iface_desc; 758 int retval = -ENOMEM; 759 int res; 760 761 /* allocate memory for our device state and initialize it */ 762 dev = kzalloc(sizeof(struct iowarrior), GFP_KERNEL); 763 if (!dev) 764 return retval; 765 766 mutex_init(&dev->mutex); 767 768 atomic_set(&dev->intr_idx, 0); 769 atomic_set(&dev->read_idx, 0); 770 atomic_set(&dev->overflow_flag, 0); 771 init_waitqueue_head(&dev->read_wait); 772 atomic_set(&dev->write_busy, 0); 773 init_waitqueue_head(&dev->write_wait); 774 775 dev->udev = udev; 776 dev->interface = usb_get_intf(interface); 777 778 iface_desc = interface->cur_altsetting; 779 dev->product_id = le16_to_cpu(udev->descriptor.idProduct); 780 781 init_usb_anchor(&dev->submitted); 782 783 res = usb_find_last_int_in_endpoint(iface_desc, &dev->int_in_endpoint); 784 if (res) { 785 dev_err(&interface->dev, "no interrupt-in endpoint found\n"); 786 retval = res; 787 goto error; 788 } 789 790 if ((dev->product_id == USB_DEVICE_ID_CODEMERCS_IOW56) || 791 (dev->product_id == USB_DEVICE_ID_CODEMERCS_IOW56AM) || 792 (dev->product_id == USB_DEVICE_ID_CODEMERCS_IOW28) || 793 (dev->product_id == USB_DEVICE_ID_CODEMERCS_IOW28L) || 794 (dev->product_id == USB_DEVICE_ID_CODEMERCS_IOW100)) { 795 res = usb_find_last_int_out_endpoint(iface_desc, 796 &dev->int_out_endpoint); 797 if (res) { 798 dev_err(&interface->dev, "no interrupt-out endpoint found\n"); 799 retval = res; 800 goto error; 801 } 802 } 803 804 /* we have to check the report_size often, so remember it in the endianness suitable for our machine */ 805 dev->report_size = usb_endpoint_maxp(dev->int_in_endpoint); 806 807 /* 808 * Some devices need the report size to be different than the 809 * endpoint size. 810 */ 811 if (dev->interface->cur_altsetting->desc.bInterfaceNumber == 0) { 812 switch (dev->product_id) { 813 case USB_DEVICE_ID_CODEMERCS_IOW56: 814 case USB_DEVICE_ID_CODEMERCS_IOW56AM: 815 dev->report_size = 7; 816 break; 817 818 case USB_DEVICE_ID_CODEMERCS_IOW28: 819 case USB_DEVICE_ID_CODEMERCS_IOW28L: 820 dev->report_size = 4; 821 break; 822 823 case USB_DEVICE_ID_CODEMERCS_IOW100: 824 dev->report_size = 13; 825 break; 826 } 827 } 828 829 /* create the urb and buffer for reading */ 830 dev->int_in_urb = usb_alloc_urb(0, GFP_KERNEL); 831 if (!dev->int_in_urb) 832 goto error; 833 dev->int_in_buffer = kmalloc(dev->report_size, GFP_KERNEL); 834 if (!dev->int_in_buffer) 835 goto error; 836 usb_fill_int_urb(dev->int_in_urb, dev->udev, 837 usb_rcvintpipe(dev->udev, 838 dev->int_in_endpoint->bEndpointAddress), 839 dev->int_in_buffer, dev->report_size, 840 iowarrior_callback, dev, 841 dev->int_in_endpoint->bInterval); 842 /* create an internal buffer for interrupt data from the device */ 843 dev->read_queue = 844 kmalloc_array(dev->report_size + 1, MAX_INTERRUPT_BUFFER, 845 GFP_KERNEL); 846 if (!dev->read_queue) 847 goto error; 848 /* Get the serial-number of the chip */ 849 memset(dev->chip_serial, 0x00, sizeof(dev->chip_serial)); 850 usb_string(udev, udev->descriptor.iSerialNumber, dev->chip_serial, 851 sizeof(dev->chip_serial)); 852 if (strlen(dev->chip_serial) != 8) 853 memset(dev->chip_serial, 0x00, sizeof(dev->chip_serial)); 854 855 /* Set the idle timeout to 0, if this is interface 0 */ 856 if (dev->interface->cur_altsetting->desc.bInterfaceNumber == 0) { 857 usb_control_msg(udev, usb_sndctrlpipe(udev, 0), 858 0x0A, 859 USB_TYPE_CLASS | USB_RECIP_INTERFACE, 0, 860 0, NULL, 0, USB_CTRL_SET_TIMEOUT); 861 } 862 /* allow device read and ioctl */ 863 dev->present = 1; 864 865 /* we can register the device now, as it is ready */ 866 usb_set_intfdata(interface, dev); 867 868 retval = usb_register_dev(interface, &iowarrior_class); 869 if (retval) { 870 /* something prevented us from registering this driver */ 871 dev_err(&interface->dev, "Not able to get a minor for this device.\n"); 872 goto error; 873 } 874 875 dev->minor = interface->minor; 876 877 /* let the user know what node this device is now attached to */ 878 dev_info(&interface->dev, "IOWarrior product=0x%x, serial=%s interface=%d " 879 "now attached to iowarrior%d\n", dev->product_id, dev->chip_serial, 880 iface_desc->desc.bInterfaceNumber, dev->minor - IOWARRIOR_MINOR_BASE); 881 return retval; 882 883 error: 884 iowarrior_delete(dev); 885 return retval; 886 } 887 888 /* 889 * iowarrior_disconnect 890 * 891 * Called by the usb core when the device is removed from the system. 892 */ 893 static void iowarrior_disconnect(struct usb_interface *interface) 894 { 895 struct iowarrior *dev = usb_get_intfdata(interface); 896 int minor = dev->minor; 897 898 usb_deregister_dev(interface, &iowarrior_class); 899 900 mutex_lock(&dev->mutex); 901 902 /* prevent device read, write and ioctl */ 903 dev->present = 0; 904 905 if (dev->opened) { 906 /* There is a process that holds a filedescriptor to the device , 907 so we only shutdown read-/write-ops going on. 908 Deleting the device is postponed until close() was called. 909 */ 910 usb_kill_urb(dev->int_in_urb); 911 usb_kill_anchored_urbs(&dev->submitted); 912 wake_up_interruptible(&dev->read_wait); 913 wake_up_interruptible(&dev->write_wait); 914 mutex_unlock(&dev->mutex); 915 } else { 916 /* no process is using the device, cleanup now */ 917 mutex_unlock(&dev->mutex); 918 iowarrior_delete(dev); 919 } 920 921 dev_info(&interface->dev, "I/O-Warror #%d now disconnected\n", 922 minor - IOWARRIOR_MINOR_BASE); 923 } 924 925 /* usb specific object needed to register this driver with the usb subsystem */ 926 static struct usb_driver iowarrior_driver = { 927 .name = "iowarrior", 928 .probe = iowarrior_probe, 929 .disconnect = iowarrior_disconnect, 930 .id_table = iowarrior_ids, 931 }; 932 933 module_usb_driver(iowarrior_driver); 934