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 #define USB_REQ_GET_REPORT 0x01 103 //#if 0 104 static int usb_get_report(struct usb_device *dev, 105 struct usb_host_interface *inter, unsigned char type, 106 unsigned char id, void *buf, int size) 107 { 108 return usb_control_msg(dev, usb_rcvctrlpipe(dev, 0), 109 USB_REQ_GET_REPORT, 110 USB_DIR_IN | USB_TYPE_CLASS | 111 USB_RECIP_INTERFACE, (type << 8) + id, 112 inter->desc.bInterfaceNumber, buf, size, 113 USB_CTRL_GET_TIMEOUT); 114 } 115 //#endif 116 117 #define USB_REQ_SET_REPORT 0x09 118 119 static int usb_set_report(struct usb_interface *intf, unsigned char type, 120 unsigned char id, void *buf, int size) 121 { 122 return usb_control_msg(interface_to_usbdev(intf), 123 usb_sndctrlpipe(interface_to_usbdev(intf), 0), 124 USB_REQ_SET_REPORT, 125 USB_TYPE_CLASS | USB_RECIP_INTERFACE, 126 (type << 8) + id, 127 intf->cur_altsetting->desc.bInterfaceNumber, buf, 128 size, 1000); 129 } 130 131 /*---------------------*/ 132 /* driver registration */ 133 /*---------------------*/ 134 /* table of devices that work with this driver */ 135 static const struct usb_device_id iowarrior_ids[] = { 136 {USB_DEVICE(USB_VENDOR_ID_CODEMERCS, USB_DEVICE_ID_CODEMERCS_IOW40)}, 137 {USB_DEVICE(USB_VENDOR_ID_CODEMERCS, USB_DEVICE_ID_CODEMERCS_IOW24)}, 138 {USB_DEVICE(USB_VENDOR_ID_CODEMERCS, USB_DEVICE_ID_CODEMERCS_IOWPV1)}, 139 {USB_DEVICE(USB_VENDOR_ID_CODEMERCS, USB_DEVICE_ID_CODEMERCS_IOWPV2)}, 140 {USB_DEVICE(USB_VENDOR_ID_CODEMERCS, USB_DEVICE_ID_CODEMERCS_IOW56)}, 141 {USB_DEVICE(USB_VENDOR_ID_CODEMERCS, USB_DEVICE_ID_CODEMERCS_IOW24SAG)}, 142 {USB_DEVICE(USB_VENDOR_ID_CODEMERCS, USB_DEVICE_ID_CODEMERCS_IOW56AM)}, 143 {USB_DEVICE(USB_VENDOR_ID_CODEMERCS, USB_DEVICE_ID_CODEMERCS_IOW28)}, 144 {USB_DEVICE(USB_VENDOR_ID_CODEMERCS, USB_DEVICE_ID_CODEMERCS_IOW28L)}, 145 {USB_DEVICE(USB_VENDOR_ID_CODEMERCS, USB_DEVICE_ID_CODEMERCS_IOW100)}, 146 {} /* Terminating entry */ 147 }; 148 MODULE_DEVICE_TABLE(usb, iowarrior_ids); 149 150 /* 151 * USB callback handler for reading data 152 */ 153 static void iowarrior_callback(struct urb *urb) 154 { 155 struct iowarrior *dev = urb->context; 156 int intr_idx; 157 int read_idx; 158 int aux_idx; 159 int offset; 160 int status = urb->status; 161 int retval; 162 163 switch (status) { 164 case 0: 165 /* success */ 166 break; 167 case -ECONNRESET: 168 case -ENOENT: 169 case -ESHUTDOWN: 170 return; 171 default: 172 goto exit; 173 } 174 175 intr_idx = atomic_read(&dev->intr_idx); 176 /* aux_idx become previous intr_idx */ 177 aux_idx = (intr_idx == 0) ? (MAX_INTERRUPT_BUFFER - 1) : (intr_idx - 1); 178 read_idx = atomic_read(&dev->read_idx); 179 180 /* queue is not empty and it's interface 0 */ 181 if ((intr_idx != read_idx) 182 && (dev->interface->cur_altsetting->desc.bInterfaceNumber == 0)) { 183 /* + 1 for serial number */ 184 offset = aux_idx * (dev->report_size + 1); 185 if (!memcmp 186 (dev->read_queue + offset, urb->transfer_buffer, 187 dev->report_size)) { 188 /* equal values on interface 0 will be ignored */ 189 goto exit; 190 } 191 } 192 193 /* aux_idx become next intr_idx */ 194 aux_idx = (intr_idx == (MAX_INTERRUPT_BUFFER - 1)) ? 0 : (intr_idx + 1); 195 if (read_idx == aux_idx) { 196 /* queue full, dropping oldest input */ 197 read_idx = (++read_idx == MAX_INTERRUPT_BUFFER) ? 0 : read_idx; 198 atomic_set(&dev->read_idx, read_idx); 199 atomic_set(&dev->overflow_flag, 1); 200 } 201 202 /* +1 for serial number */ 203 offset = intr_idx * (dev->report_size + 1); 204 memcpy(dev->read_queue + offset, urb->transfer_buffer, 205 dev->report_size); 206 *(dev->read_queue + offset + (dev->report_size)) = dev->serial_number++; 207 208 atomic_set(&dev->intr_idx, aux_idx); 209 /* tell the blocking read about the new data */ 210 wake_up_interruptible(&dev->read_wait); 211 212 exit: 213 retval = usb_submit_urb(urb, GFP_ATOMIC); 214 if (retval) 215 dev_err(&dev->interface->dev, "%s - usb_submit_urb failed with result %d\n", 216 __func__, retval); 217 218 } 219 220 /* 221 * USB Callback handler for write-ops 222 */ 223 static void iowarrior_write_callback(struct urb *urb) 224 { 225 struct iowarrior *dev; 226 int status = urb->status; 227 228 dev = urb->context; 229 /* sync/async unlink faults aren't errors */ 230 if (status && 231 !(status == -ENOENT || 232 status == -ECONNRESET || status == -ESHUTDOWN)) { 233 dev_dbg(&dev->interface->dev, 234 "nonzero write bulk status received: %d\n", status); 235 } 236 /* free up our allocated buffer */ 237 usb_free_coherent(urb->dev, urb->transfer_buffer_length, 238 urb->transfer_buffer, urb->transfer_dma); 239 /* tell a waiting writer the interrupt-out-pipe is available again */ 240 atomic_dec(&dev->write_busy); 241 wake_up_interruptible(&dev->write_wait); 242 } 243 244 /* 245 * iowarrior_delete 246 */ 247 static inline void iowarrior_delete(struct iowarrior *dev) 248 { 249 dev_dbg(&dev->interface->dev, "minor %d\n", dev->minor); 250 kfree(dev->int_in_buffer); 251 usb_free_urb(dev->int_in_urb); 252 kfree(dev->read_queue); 253 usb_put_intf(dev->interface); 254 kfree(dev); 255 } 256 257 /*---------------------*/ 258 /* fops implementation */ 259 /*---------------------*/ 260 261 static int read_index(struct iowarrior *dev) 262 { 263 int intr_idx, read_idx; 264 265 read_idx = atomic_read(&dev->read_idx); 266 intr_idx = atomic_read(&dev->intr_idx); 267 268 return (read_idx == intr_idx ? -1 : read_idx); 269 } 270 271 /* 272 * iowarrior_read 273 */ 274 static ssize_t iowarrior_read(struct file *file, char __user *buffer, 275 size_t count, loff_t *ppos) 276 { 277 struct iowarrior *dev; 278 int read_idx; 279 int offset; 280 int retval; 281 282 dev = file->private_data; 283 284 if (file->f_flags & O_NONBLOCK) { 285 retval = mutex_trylock(&dev->mutex); 286 if (!retval) 287 return -EAGAIN; 288 } else { 289 retval = mutex_lock_interruptible(&dev->mutex); 290 if (retval) 291 return -ERESTARTSYS; 292 } 293 294 /* verify that the device wasn't unplugged */ 295 if (!dev->present) { 296 retval = -ENODEV; 297 goto exit; 298 } 299 300 dev_dbg(&dev->interface->dev, "minor %d, count = %zd\n", 301 dev->minor, count); 302 303 /* read count must be packet size (+ time stamp) */ 304 if ((count != dev->report_size) 305 && (count != (dev->report_size + 1))) { 306 retval = -EINVAL; 307 goto exit; 308 } 309 310 /* repeat until no buffer overrun in callback handler occur */ 311 do { 312 atomic_set(&dev->overflow_flag, 0); 313 if ((read_idx = read_index(dev)) == -1) { 314 /* queue empty */ 315 if (file->f_flags & O_NONBLOCK) { 316 retval = -EAGAIN; 317 goto exit; 318 } 319 else { 320 //next line will return when there is either new data, or the device is unplugged 321 int r = wait_event_interruptible(dev->read_wait, 322 (!dev->present 323 || (read_idx = 324 read_index 325 (dev)) != 326 -1)); 327 if (r) { 328 //we were interrupted by a signal 329 retval = -ERESTART; 330 goto exit; 331 } 332 if (!dev->present) { 333 //The device was unplugged 334 retval = -ENODEV; 335 goto exit; 336 } 337 if (read_idx == -1) { 338 // Can this happen ??? 339 retval = 0; 340 goto exit; 341 } 342 } 343 } 344 345 offset = read_idx * (dev->report_size + 1); 346 if (copy_to_user(buffer, dev->read_queue + offset, count)) { 347 retval = -EFAULT; 348 goto exit; 349 } 350 } while (atomic_read(&dev->overflow_flag)); 351 352 read_idx = ++read_idx == MAX_INTERRUPT_BUFFER ? 0 : read_idx; 353 atomic_set(&dev->read_idx, read_idx); 354 mutex_unlock(&dev->mutex); 355 return count; 356 357 exit: 358 mutex_unlock(&dev->mutex); 359 return retval; 360 } 361 362 /* 363 * iowarrior_write 364 */ 365 static ssize_t iowarrior_write(struct file *file, 366 const char __user *user_buffer, 367 size_t count, loff_t *ppos) 368 { 369 struct iowarrior *dev; 370 int retval = 0; 371 char *buf = NULL; /* for IOW24 and IOW56 we need a buffer */ 372 struct urb *int_out_urb = NULL; 373 374 dev = file->private_data; 375 376 mutex_lock(&dev->mutex); 377 /* verify that the device wasn't unplugged */ 378 if (!dev->present) { 379 retval = -ENODEV; 380 goto exit; 381 } 382 dev_dbg(&dev->interface->dev, "minor %d, count = %zd\n", 383 dev->minor, count); 384 /* if count is 0 we're already done */ 385 if (count == 0) { 386 retval = 0; 387 goto exit; 388 } 389 /* We only accept full reports */ 390 if (count != dev->report_size) { 391 retval = -EINVAL; 392 goto exit; 393 } 394 switch (dev->product_id) { 395 case USB_DEVICE_ID_CODEMERCS_IOW24: 396 case USB_DEVICE_ID_CODEMERCS_IOW24SAG: 397 case USB_DEVICE_ID_CODEMERCS_IOWPV1: 398 case USB_DEVICE_ID_CODEMERCS_IOWPV2: 399 case USB_DEVICE_ID_CODEMERCS_IOW40: 400 /* IOW24 and IOW40 use a synchronous call */ 401 buf = memdup_user(user_buffer, count); 402 if (IS_ERR(buf)) { 403 retval = PTR_ERR(buf); 404 goto exit; 405 } 406 retval = usb_set_report(dev->interface, 2, 0, buf, count); 407 kfree(buf); 408 goto exit; 409 case USB_DEVICE_ID_CODEMERCS_IOW56: 410 case USB_DEVICE_ID_CODEMERCS_IOW56AM: 411 case USB_DEVICE_ID_CODEMERCS_IOW28: 412 case USB_DEVICE_ID_CODEMERCS_IOW28L: 413 case USB_DEVICE_ID_CODEMERCS_IOW100: 414 /* The IOW56 uses asynchronous IO and more urbs */ 415 if (atomic_read(&dev->write_busy) == MAX_WRITES_IN_FLIGHT) { 416 /* Wait until we are below the limit for submitted urbs */ 417 if (file->f_flags & O_NONBLOCK) { 418 retval = -EAGAIN; 419 goto exit; 420 } else { 421 retval = wait_event_interruptible(dev->write_wait, 422 (!dev->present || (atomic_read (&dev-> write_busy) < MAX_WRITES_IN_FLIGHT))); 423 if (retval) { 424 /* we were interrupted by a signal */ 425 retval = -ERESTART; 426 goto exit; 427 } 428 if (!dev->present) { 429 /* The device was unplugged */ 430 retval = -ENODEV; 431 goto exit; 432 } 433 if (!dev->opened) { 434 /* We were closed while waiting for an URB */ 435 retval = -ENODEV; 436 goto exit; 437 } 438 } 439 } 440 atomic_inc(&dev->write_busy); 441 int_out_urb = usb_alloc_urb(0, GFP_KERNEL); 442 if (!int_out_urb) { 443 retval = -ENOMEM; 444 goto error_no_urb; 445 } 446 buf = usb_alloc_coherent(dev->udev, dev->report_size, 447 GFP_KERNEL, &int_out_urb->transfer_dma); 448 if (!buf) { 449 retval = -ENOMEM; 450 dev_dbg(&dev->interface->dev, 451 "Unable to allocate buffer\n"); 452 goto error_no_buffer; 453 } 454 usb_fill_int_urb(int_out_urb, dev->udev, 455 usb_sndintpipe(dev->udev, 456 dev->int_out_endpoint->bEndpointAddress), 457 buf, dev->report_size, 458 iowarrior_write_callback, dev, 459 dev->int_out_endpoint->bInterval); 460 int_out_urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP; 461 if (copy_from_user(buf, user_buffer, count)) { 462 retval = -EFAULT; 463 goto error; 464 } 465 usb_anchor_urb(int_out_urb, &dev->submitted); 466 retval = usb_submit_urb(int_out_urb, GFP_KERNEL); 467 if (retval) { 468 dev_dbg(&dev->interface->dev, 469 "submit error %d for urb nr.%d\n", 470 retval, atomic_read(&dev->write_busy)); 471 usb_unanchor_urb(int_out_urb); 472 goto error; 473 } 474 /* submit was ok */ 475 retval = count; 476 usb_free_urb(int_out_urb); 477 goto exit; 478 default: 479 /* what do we have here ? An unsupported Product-ID ? */ 480 dev_err(&dev->interface->dev, "%s - not supported for product=0x%x\n", 481 __func__, dev->product_id); 482 retval = -EFAULT; 483 goto exit; 484 } 485 error: 486 usb_free_coherent(dev->udev, dev->report_size, buf, 487 int_out_urb->transfer_dma); 488 error_no_buffer: 489 usb_free_urb(int_out_urb); 490 error_no_urb: 491 atomic_dec(&dev->write_busy); 492 wake_up_interruptible(&dev->write_wait); 493 exit: 494 mutex_unlock(&dev->mutex); 495 return retval; 496 } 497 498 /* 499 * iowarrior_ioctl 500 */ 501 static long iowarrior_ioctl(struct file *file, unsigned int cmd, 502 unsigned long arg) 503 { 504 struct iowarrior *dev = NULL; 505 __u8 *buffer; 506 __u8 __user *user_buffer; 507 int retval; 508 int io_res; /* checks for bytes read/written and copy_to/from_user results */ 509 510 dev = file->private_data; 511 if (!dev) 512 return -ENODEV; 513 514 buffer = kzalloc(dev->report_size, GFP_KERNEL); 515 if (!buffer) 516 return -ENOMEM; 517 518 mutex_lock(&dev->mutex); 519 520 /* verify that the device wasn't unplugged */ 521 if (!dev->present) { 522 retval = -ENODEV; 523 goto error_out; 524 } 525 526 dev_dbg(&dev->interface->dev, "minor %d, cmd 0x%.4x, arg %ld\n", 527 dev->minor, cmd, arg); 528 529 retval = 0; 530 switch (cmd) { 531 case IOW_WRITE: 532 if (dev->product_id == USB_DEVICE_ID_CODEMERCS_IOW24 || 533 dev->product_id == USB_DEVICE_ID_CODEMERCS_IOW24SAG || 534 dev->product_id == USB_DEVICE_ID_CODEMERCS_IOWPV1 || 535 dev->product_id == USB_DEVICE_ID_CODEMERCS_IOWPV2 || 536 dev->product_id == USB_DEVICE_ID_CODEMERCS_IOW40) { 537 user_buffer = (__u8 __user *)arg; 538 io_res = copy_from_user(buffer, user_buffer, 539 dev->report_size); 540 if (io_res) { 541 retval = -EFAULT; 542 } else { 543 io_res = usb_set_report(dev->interface, 2, 0, 544 buffer, 545 dev->report_size); 546 if (io_res < 0) 547 retval = io_res; 548 } 549 } else { 550 retval = -EINVAL; 551 dev_err(&dev->interface->dev, 552 "ioctl 'IOW_WRITE' is not supported for product=0x%x.\n", 553 dev->product_id); 554 } 555 break; 556 case IOW_READ: 557 user_buffer = (__u8 __user *)arg; 558 io_res = usb_get_report(dev->udev, 559 dev->interface->cur_altsetting, 1, 0, 560 buffer, dev->report_size); 561 if (io_res < 0) 562 retval = io_res; 563 else { 564 io_res = copy_to_user(user_buffer, buffer, dev->report_size); 565 if (io_res) 566 retval = -EFAULT; 567 } 568 break; 569 case IOW_GETINFO: 570 { 571 /* Report available information for the device */ 572 struct iowarrior_info info; 573 /* needed for power consumption */ 574 struct usb_config_descriptor *cfg_descriptor = &dev->udev->actconfig->desc; 575 576 memset(&info, 0, sizeof(info)); 577 /* directly from the descriptor */ 578 info.vendor = le16_to_cpu(dev->udev->descriptor.idVendor); 579 info.product = dev->product_id; 580 info.revision = le16_to_cpu(dev->udev->descriptor.bcdDevice); 581 582 /* 0==UNKNOWN, 1==LOW(usb1.1) ,2=FULL(usb1.1), 3=HIGH(usb2.0) */ 583 info.speed = dev->udev->speed; 584 info.if_num = dev->interface->cur_altsetting->desc.bInterfaceNumber; 585 info.report_size = dev->report_size; 586 587 /* serial number string has been read earlier 8 chars or empty string */ 588 memcpy(info.serial, dev->chip_serial, 589 sizeof(dev->chip_serial)); 590 if (cfg_descriptor == NULL) { 591 info.power = -1; /* no information available */ 592 } else { 593 /* the MaxPower is stored in units of 2mA to make it fit into a byte-value */ 594 info.power = cfg_descriptor->bMaxPower * 2; 595 } 596 io_res = copy_to_user((struct iowarrior_info __user *)arg, &info, 597 sizeof(struct iowarrior_info)); 598 if (io_res) 599 retval = -EFAULT; 600 break; 601 } 602 default: 603 /* return that we did not understand this ioctl call */ 604 retval = -ENOTTY; 605 break; 606 } 607 error_out: 608 /* unlock the device */ 609 mutex_unlock(&dev->mutex); 610 kfree(buffer); 611 return retval; 612 } 613 614 /* 615 * iowarrior_open 616 */ 617 static int iowarrior_open(struct inode *inode, struct file *file) 618 { 619 struct iowarrior *dev = NULL; 620 struct usb_interface *interface; 621 int subminor; 622 int retval = 0; 623 624 subminor = iminor(inode); 625 626 interface = usb_find_interface(&iowarrior_driver, subminor); 627 if (!interface) { 628 pr_err("%s - error, can't find device for minor %d\n", 629 __func__, subminor); 630 return -ENODEV; 631 } 632 633 dev = usb_get_intfdata(interface); 634 if (!dev) 635 return -ENODEV; 636 637 mutex_lock(&dev->mutex); 638 639 /* Only one process can open each device, no sharing. */ 640 if (dev->opened) { 641 retval = -EBUSY; 642 goto out; 643 } 644 645 /* setup interrupt handler for receiving values */ 646 if ((retval = usb_submit_urb(dev->int_in_urb, GFP_KERNEL)) < 0) { 647 dev_err(&interface->dev, "Error %d while submitting URB\n", retval); 648 retval = -EFAULT; 649 goto out; 650 } 651 /* increment our usage count for the driver */ 652 ++dev->opened; 653 /* save our object in the file's private structure */ 654 file->private_data = dev; 655 retval = 0; 656 657 out: 658 mutex_unlock(&dev->mutex); 659 return retval; 660 } 661 662 /* 663 * iowarrior_release 664 */ 665 static int iowarrior_release(struct inode *inode, struct file *file) 666 { 667 struct iowarrior *dev; 668 int retval = 0; 669 670 dev = file->private_data; 671 if (!dev) 672 return -ENODEV; 673 674 dev_dbg(&dev->interface->dev, "minor %d\n", dev->minor); 675 676 /* lock our device */ 677 mutex_lock(&dev->mutex); 678 679 if (dev->opened <= 0) { 680 retval = -ENODEV; /* close called more than once */ 681 mutex_unlock(&dev->mutex); 682 } else { 683 dev->opened = 0; /* we're closing now */ 684 retval = 0; 685 if (dev->present) { 686 /* 687 The device is still connected so we only shutdown 688 pending read-/write-ops. 689 */ 690 usb_kill_urb(dev->int_in_urb); 691 wake_up_interruptible(&dev->read_wait); 692 wake_up_interruptible(&dev->write_wait); 693 mutex_unlock(&dev->mutex); 694 } else { 695 /* The device was unplugged, cleanup resources */ 696 mutex_unlock(&dev->mutex); 697 iowarrior_delete(dev); 698 } 699 } 700 return retval; 701 } 702 703 static __poll_t iowarrior_poll(struct file *file, poll_table * wait) 704 { 705 struct iowarrior *dev = file->private_data; 706 __poll_t mask = 0; 707 708 if (!dev->present) 709 return EPOLLERR | EPOLLHUP; 710 711 poll_wait(file, &dev->read_wait, wait); 712 poll_wait(file, &dev->write_wait, wait); 713 714 if (!dev->present) 715 return EPOLLERR | EPOLLHUP; 716 717 if (read_index(dev) != -1) 718 mask |= EPOLLIN | EPOLLRDNORM; 719 720 if (atomic_read(&dev->write_busy) < MAX_WRITES_IN_FLIGHT) 721 mask |= EPOLLOUT | EPOLLWRNORM; 722 return mask; 723 } 724 725 /* 726 * File operations needed when we register this driver. 727 * This assumes that this driver NEEDS file operations, 728 * of course, which means that the driver is expected 729 * to have a node in the /dev directory. If the USB 730 * device were for a network interface then the driver 731 * would use "struct net_driver" instead, and a serial 732 * device would use "struct tty_driver". 733 */ 734 static const struct file_operations iowarrior_fops = { 735 .owner = THIS_MODULE, 736 .write = iowarrior_write, 737 .read = iowarrior_read, 738 .unlocked_ioctl = iowarrior_ioctl, 739 .open = iowarrior_open, 740 .release = iowarrior_release, 741 .poll = iowarrior_poll, 742 .llseek = noop_llseek, 743 }; 744 745 static char *iowarrior_devnode(const struct device *dev, umode_t *mode) 746 { 747 return kasprintf(GFP_KERNEL, "usb/%s", dev_name(dev)); 748 } 749 750 /* 751 * usb class driver info in order to get a minor number from the usb core, 752 * and to have the device registered with devfs and the driver core 753 */ 754 static struct usb_class_driver iowarrior_class = { 755 .name = "iowarrior%d", 756 .devnode = iowarrior_devnode, 757 .fops = &iowarrior_fops, 758 .minor_base = IOWARRIOR_MINOR_BASE, 759 }; 760 761 /*---------------------------------*/ 762 /* probe and disconnect functions */ 763 /*---------------------------------*/ 764 /* 765 * iowarrior_probe 766 * 767 * Called by the usb core when a new device is connected that it thinks 768 * this driver might be interested in. 769 */ 770 static int iowarrior_probe(struct usb_interface *interface, 771 const struct usb_device_id *id) 772 { 773 struct usb_device *udev = interface_to_usbdev(interface); 774 struct iowarrior *dev = NULL; 775 struct usb_host_interface *iface_desc; 776 int retval = -ENOMEM; 777 int res; 778 779 /* allocate memory for our device state and initialize it */ 780 dev = kzalloc(sizeof(struct iowarrior), GFP_KERNEL); 781 if (!dev) 782 return retval; 783 784 mutex_init(&dev->mutex); 785 786 atomic_set(&dev->intr_idx, 0); 787 atomic_set(&dev->read_idx, 0); 788 atomic_set(&dev->overflow_flag, 0); 789 init_waitqueue_head(&dev->read_wait); 790 atomic_set(&dev->write_busy, 0); 791 init_waitqueue_head(&dev->write_wait); 792 793 dev->udev = udev; 794 dev->interface = usb_get_intf(interface); 795 796 iface_desc = interface->cur_altsetting; 797 dev->product_id = le16_to_cpu(udev->descriptor.idProduct); 798 799 init_usb_anchor(&dev->submitted); 800 801 res = usb_find_last_int_in_endpoint(iface_desc, &dev->int_in_endpoint); 802 if (res) { 803 dev_err(&interface->dev, "no interrupt-in endpoint found\n"); 804 retval = res; 805 goto error; 806 } 807 808 if ((dev->product_id == USB_DEVICE_ID_CODEMERCS_IOW56) || 809 (dev->product_id == USB_DEVICE_ID_CODEMERCS_IOW56AM) || 810 (dev->product_id == USB_DEVICE_ID_CODEMERCS_IOW28) || 811 (dev->product_id == USB_DEVICE_ID_CODEMERCS_IOW28L) || 812 (dev->product_id == USB_DEVICE_ID_CODEMERCS_IOW100)) { 813 res = usb_find_last_int_out_endpoint(iface_desc, 814 &dev->int_out_endpoint); 815 if (res) { 816 dev_err(&interface->dev, "no interrupt-out endpoint found\n"); 817 retval = res; 818 goto error; 819 } 820 } 821 822 /* we have to check the report_size often, so remember it in the endianness suitable for our machine */ 823 dev->report_size = usb_endpoint_maxp(dev->int_in_endpoint); 824 825 /* 826 * Some devices need the report size to be different than the 827 * endpoint size. 828 */ 829 if (dev->interface->cur_altsetting->desc.bInterfaceNumber == 0) { 830 switch (dev->product_id) { 831 case USB_DEVICE_ID_CODEMERCS_IOW56: 832 case USB_DEVICE_ID_CODEMERCS_IOW56AM: 833 dev->report_size = 7; 834 break; 835 836 case USB_DEVICE_ID_CODEMERCS_IOW28: 837 case USB_DEVICE_ID_CODEMERCS_IOW28L: 838 dev->report_size = 4; 839 break; 840 841 case USB_DEVICE_ID_CODEMERCS_IOW100: 842 dev->report_size = 12; 843 break; 844 } 845 } 846 847 /* create the urb and buffer for reading */ 848 dev->int_in_urb = usb_alloc_urb(0, GFP_KERNEL); 849 if (!dev->int_in_urb) 850 goto error; 851 dev->int_in_buffer = kmalloc(dev->report_size, GFP_KERNEL); 852 if (!dev->int_in_buffer) 853 goto error; 854 usb_fill_int_urb(dev->int_in_urb, dev->udev, 855 usb_rcvintpipe(dev->udev, 856 dev->int_in_endpoint->bEndpointAddress), 857 dev->int_in_buffer, dev->report_size, 858 iowarrior_callback, dev, 859 dev->int_in_endpoint->bInterval); 860 /* create an internal buffer for interrupt data from the device */ 861 dev->read_queue = 862 kmalloc_array(dev->report_size + 1, MAX_INTERRUPT_BUFFER, 863 GFP_KERNEL); 864 if (!dev->read_queue) 865 goto error; 866 /* Get the serial-number of the chip */ 867 memset(dev->chip_serial, 0x00, sizeof(dev->chip_serial)); 868 usb_string(udev, udev->descriptor.iSerialNumber, dev->chip_serial, 869 sizeof(dev->chip_serial)); 870 if (strlen(dev->chip_serial) != 8) 871 memset(dev->chip_serial, 0x00, sizeof(dev->chip_serial)); 872 873 /* Set the idle timeout to 0, if this is interface 0 */ 874 if (dev->interface->cur_altsetting->desc.bInterfaceNumber == 0) { 875 usb_control_msg(udev, usb_sndctrlpipe(udev, 0), 876 0x0A, 877 USB_TYPE_CLASS | USB_RECIP_INTERFACE, 0, 878 0, NULL, 0, USB_CTRL_SET_TIMEOUT); 879 } 880 /* allow device read and ioctl */ 881 dev->present = 1; 882 883 /* we can register the device now, as it is ready */ 884 usb_set_intfdata(interface, dev); 885 886 retval = usb_register_dev(interface, &iowarrior_class); 887 if (retval) { 888 /* something prevented us from registering this driver */ 889 dev_err(&interface->dev, "Not able to get a minor for this device.\n"); 890 goto error; 891 } 892 893 dev->minor = interface->minor; 894 895 /* let the user know what node this device is now attached to */ 896 dev_info(&interface->dev, "IOWarrior product=0x%x, serial=%s interface=%d " 897 "now attached to iowarrior%d\n", dev->product_id, dev->chip_serial, 898 iface_desc->desc.bInterfaceNumber, dev->minor - IOWARRIOR_MINOR_BASE); 899 return retval; 900 901 error: 902 iowarrior_delete(dev); 903 return retval; 904 } 905 906 /* 907 * iowarrior_disconnect 908 * 909 * Called by the usb core when the device is removed from the system. 910 */ 911 static void iowarrior_disconnect(struct usb_interface *interface) 912 { 913 struct iowarrior *dev = usb_get_intfdata(interface); 914 915 usb_deregister_dev(interface, &iowarrior_class); 916 917 mutex_lock(&dev->mutex); 918 919 /* prevent device read, write and ioctl */ 920 dev->present = 0; 921 922 if (dev->opened) { 923 /* There is a process that holds a filedescriptor to the device , 924 so we only shutdown read-/write-ops going on. 925 Deleting the device is postponed until close() was called. 926 */ 927 usb_kill_urb(dev->int_in_urb); 928 usb_kill_anchored_urbs(&dev->submitted); 929 wake_up_interruptible(&dev->read_wait); 930 wake_up_interruptible(&dev->write_wait); 931 mutex_unlock(&dev->mutex); 932 } else { 933 /* no process is using the device, cleanup now */ 934 mutex_unlock(&dev->mutex); 935 iowarrior_delete(dev); 936 } 937 } 938 939 /* usb specific object needed to register this driver with the usb subsystem */ 940 static struct usb_driver iowarrior_driver = { 941 .name = "iowarrior", 942 .probe = iowarrior_probe, 943 .disconnect = iowarrior_disconnect, 944 .id_table = iowarrior_ids, 945 }; 946 947 module_usb_driver(iowarrior_driver); 948