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 struct usb_endpoint_descriptor *int_out_endpoint; /* endpoint for reading (needed for IOW56 only) */ 78 struct usb_endpoint_descriptor *int_in_endpoint; /* endpoint for reading */ 79 struct urb *int_in_urb; /* the urb for reading data */ 80 unsigned char *int_in_buffer; /* buffer for data to be read */ 81 unsigned char serial_number; /* to detect lost packages */ 82 unsigned char *read_queue; /* size is MAX_INTERRUPT_BUFFER * packet size */ 83 wait_queue_head_t read_wait; 84 wait_queue_head_t write_wait; /* wait-queue for writing to the device */ 85 atomic_t write_busy; /* number of write-urbs submitted */ 86 atomic_t read_idx; 87 atomic_t intr_idx; 88 atomic_t overflow_flag; /* signals an index 'rollover' */ 89 int present; /* this is 1 as long as the device is connected */ 90 int opened; /* this is 1 if the device is currently open */ 91 char chip_serial[9]; /* the serial number string of the chip connected */ 92 int report_size; /* number of bytes in a report */ 93 u16 product_id; 94 struct usb_anchor submitted; 95 }; 96 97 /*--------------*/ 98 /* globals */ 99 /*--------------*/ 100 101 #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 USB_CTRL_GET_TIMEOUT); 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, 1000); 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 {USB_DEVICE(USB_VENDOR_ID_CODEMERCS, USB_DEVICE_ID_CODEMERCS_IOW24SAG)}, 141 {USB_DEVICE(USB_VENDOR_ID_CODEMERCS, USB_DEVICE_ID_CODEMERCS_IOW56AM)}, 142 {USB_DEVICE(USB_VENDOR_ID_CODEMERCS, USB_DEVICE_ID_CODEMERCS_IOW28)}, 143 {USB_DEVICE(USB_VENDOR_ID_CODEMERCS, USB_DEVICE_ID_CODEMERCS_IOW28L)}, 144 {USB_DEVICE(USB_VENDOR_ID_CODEMERCS, USB_DEVICE_ID_CODEMERCS_IOW100)}, 145 {} /* Terminating entry */ 146 }; 147 MODULE_DEVICE_TABLE(usb, iowarrior_ids); 148 149 /* 150 * USB callback handler for reading data 151 */ 152 static void iowarrior_callback(struct urb *urb) 153 { 154 struct iowarrior *dev = urb->context; 155 int intr_idx; 156 int read_idx; 157 int aux_idx; 158 int offset; 159 int status = urb->status; 160 int retval; 161 162 switch (status) { 163 case 0: 164 /* success */ 165 break; 166 case -ECONNRESET: 167 case -ENOENT: 168 case -ESHUTDOWN: 169 return; 170 default: 171 goto exit; 172 } 173 174 intr_idx = atomic_read(&dev->intr_idx); 175 /* aux_idx become previous intr_idx */ 176 aux_idx = (intr_idx == 0) ? (MAX_INTERRUPT_BUFFER - 1) : (intr_idx - 1); 177 read_idx = atomic_read(&dev->read_idx); 178 179 /* queue is not empty and it's interface 0 */ 180 if ((intr_idx != read_idx) 181 && (dev->interface->cur_altsetting->desc.bInterfaceNumber == 0)) { 182 /* + 1 for serial number */ 183 offset = aux_idx * (dev->report_size + 1); 184 if (!memcmp 185 (dev->read_queue + offset, urb->transfer_buffer, 186 dev->report_size)) { 187 /* equal values on interface 0 will be ignored */ 188 goto exit; 189 } 190 } 191 192 /* aux_idx become next intr_idx */ 193 aux_idx = (intr_idx == (MAX_INTERRUPT_BUFFER - 1)) ? 0 : (intr_idx + 1); 194 if (read_idx == aux_idx) { 195 /* queue full, dropping oldest input */ 196 read_idx = (++read_idx == MAX_INTERRUPT_BUFFER) ? 0 : read_idx; 197 atomic_set(&dev->read_idx, read_idx); 198 atomic_set(&dev->overflow_flag, 1); 199 } 200 201 /* +1 for serial number */ 202 offset = intr_idx * (dev->report_size + 1); 203 memcpy(dev->read_queue + offset, urb->transfer_buffer, 204 dev->report_size); 205 *(dev->read_queue + offset + (dev->report_size)) = dev->serial_number++; 206 207 atomic_set(&dev->intr_idx, aux_idx); 208 /* tell the blocking read about the new data */ 209 wake_up_interruptible(&dev->read_wait); 210 211 exit: 212 retval = usb_submit_urb(urb, GFP_ATOMIC); 213 if (retval) 214 dev_err(&dev->interface->dev, "%s - usb_submit_urb failed with result %d\n", 215 __func__, retval); 216 217 } 218 219 /* 220 * USB Callback handler for write-ops 221 */ 222 static void iowarrior_write_callback(struct urb *urb) 223 { 224 struct iowarrior *dev; 225 int status = urb->status; 226 227 dev = urb->context; 228 /* sync/async unlink faults aren't errors */ 229 if (status && 230 !(status == -ENOENT || 231 status == -ECONNRESET || status == -ESHUTDOWN)) { 232 dev_dbg(&dev->interface->dev, 233 "nonzero write bulk status received: %d\n", status); 234 } 235 /* free up our allocated buffer */ 236 kfree(urb->transfer_buffer); 237 /* tell a waiting writer the interrupt-out-pipe is available again */ 238 atomic_dec(&dev->write_busy); 239 wake_up_interruptible(&dev->write_wait); 240 } 241 242 /* 243 * iowarrior_delete 244 */ 245 static inline void iowarrior_delete(struct iowarrior *dev) 246 { 247 kfree(dev->int_in_buffer); 248 usb_free_urb(dev->int_in_urb); 249 kfree(dev->read_queue); 250 usb_put_intf(dev->interface); 251 kfree(dev); 252 } 253 254 /*---------------------*/ 255 /* fops implementation */ 256 /*---------------------*/ 257 258 static int read_index(struct iowarrior *dev) 259 { 260 int intr_idx, read_idx; 261 262 read_idx = atomic_read(&dev->read_idx); 263 intr_idx = atomic_read(&dev->intr_idx); 264 265 return (read_idx == intr_idx ? -1 : read_idx); 266 } 267 268 /* 269 * iowarrior_read 270 */ 271 static ssize_t iowarrior_read(struct file *file, char __user *buffer, 272 size_t count, loff_t *ppos) 273 { 274 struct iowarrior *dev; 275 int read_idx; 276 int offset; 277 int retval; 278 279 dev = file->private_data; 280 281 if (file->f_flags & O_NONBLOCK) { 282 retval = mutex_trylock(&dev->mutex); 283 if (!retval) 284 return -EAGAIN; 285 } else { 286 retval = mutex_lock_interruptible(&dev->mutex); 287 if (retval) 288 return -ERESTARTSYS; 289 } 290 291 /* verify that the device wasn't unplugged */ 292 if (!dev->present) { 293 retval = -ENODEV; 294 goto exit; 295 } 296 297 /* read count must be packet size (+ time stamp) */ 298 if ((count != dev->report_size) 299 && (count != (dev->report_size + 1))) { 300 retval = -EINVAL; 301 goto exit; 302 } 303 304 /* repeat until no buffer overrun in callback handler occur */ 305 do { 306 atomic_set(&dev->overflow_flag, 0); 307 if ((read_idx = read_index(dev)) == -1) { 308 /* queue empty */ 309 if (file->f_flags & O_NONBLOCK) { 310 retval = -EAGAIN; 311 goto exit; 312 } 313 else { 314 //next line will return when there is either new data, or the device is unplugged 315 int r = wait_event_interruptible(dev->read_wait, 316 (!dev->present 317 || (read_idx = 318 read_index 319 (dev)) != 320 -1)); 321 if (r) { 322 //we were interrupted by a signal 323 retval = -ERESTART; 324 goto exit; 325 } 326 if (!dev->present) { 327 //The device was unplugged 328 retval = -ENODEV; 329 goto exit; 330 } 331 if (read_idx == -1) { 332 // Can this happen ??? 333 retval = 0; 334 goto exit; 335 } 336 } 337 } 338 339 offset = read_idx * (dev->report_size + 1); 340 if (copy_to_user(buffer, dev->read_queue + offset, count)) { 341 retval = -EFAULT; 342 goto exit; 343 } 344 } while (atomic_read(&dev->overflow_flag)); 345 346 read_idx = ++read_idx == MAX_INTERRUPT_BUFFER ? 0 : read_idx; 347 atomic_set(&dev->read_idx, read_idx); 348 mutex_unlock(&dev->mutex); 349 return count; 350 351 exit: 352 mutex_unlock(&dev->mutex); 353 return retval; 354 } 355 356 /* 357 * iowarrior_write 358 */ 359 static ssize_t iowarrior_write(struct file *file, 360 const char __user *user_buffer, 361 size_t count, loff_t *ppos) 362 { 363 struct iowarrior *dev; 364 int retval; 365 char *buf = NULL; /* for IOW24 and IOW56 we need a buffer */ 366 struct urb *int_out_urb = NULL; 367 368 dev = file->private_data; 369 370 retval = mutex_lock_interruptible(&dev->mutex); 371 if (retval < 0) 372 return -EINTR; 373 374 /* verify that the device wasn't unplugged */ 375 if (!dev->present) { 376 retval = -ENODEV; 377 goto exit; 378 } 379 /* if count is 0 we're already done */ 380 if (count == 0) { 381 retval = 0; 382 goto exit; 383 } 384 /* We only accept full reports */ 385 if (count != dev->report_size) { 386 retval = -EINVAL; 387 goto exit; 388 } 389 switch (dev->product_id) { 390 case USB_DEVICE_ID_CODEMERCS_IOW24: 391 case USB_DEVICE_ID_CODEMERCS_IOW24SAG: 392 case USB_DEVICE_ID_CODEMERCS_IOWPV1: 393 case USB_DEVICE_ID_CODEMERCS_IOWPV2: 394 case USB_DEVICE_ID_CODEMERCS_IOW40: 395 /* IOW24 and IOW40 use a synchronous call */ 396 buf = memdup_user(user_buffer, count); 397 if (IS_ERR(buf)) { 398 retval = PTR_ERR(buf); 399 goto exit; 400 } 401 retval = usb_set_report(dev->interface, 2, 0, buf, count); 402 kfree(buf); 403 goto exit; 404 case USB_DEVICE_ID_CODEMERCS_IOW56: 405 case USB_DEVICE_ID_CODEMERCS_IOW56AM: 406 case USB_DEVICE_ID_CODEMERCS_IOW28: 407 case USB_DEVICE_ID_CODEMERCS_IOW28L: 408 case USB_DEVICE_ID_CODEMERCS_IOW100: 409 /* The IOW56 uses asynchronous IO and more urbs */ 410 if (atomic_read(&dev->write_busy) == MAX_WRITES_IN_FLIGHT) { 411 /* Wait until we are below the limit for submitted urbs */ 412 if (file->f_flags & O_NONBLOCK) { 413 retval = -EAGAIN; 414 goto exit; 415 } else { 416 retval = wait_event_interruptible(dev->write_wait, 417 (!dev->present || (atomic_read (&dev-> write_busy) < MAX_WRITES_IN_FLIGHT))); 418 if (retval) { 419 /* we were interrupted by a signal */ 420 retval = -ERESTART; 421 goto exit; 422 } 423 if (!dev->present) { 424 /* The device was unplugged */ 425 retval = -ENODEV; 426 goto exit; 427 } 428 if (!dev->opened) { 429 /* We were closed while waiting for an URB */ 430 retval = -ENODEV; 431 goto exit; 432 } 433 } 434 } 435 atomic_inc(&dev->write_busy); 436 int_out_urb = usb_alloc_urb(0, GFP_KERNEL); 437 if (!int_out_urb) { 438 retval = -ENOMEM; 439 goto error_no_urb; 440 } 441 buf = kmalloc(dev->report_size, GFP_KERNEL); 442 if (!buf) { 443 retval = -ENOMEM; 444 dev_dbg(&dev->interface->dev, 445 "Unable to allocate buffer\n"); 446 goto error_no_buffer; 447 } 448 usb_fill_int_urb(int_out_urb, dev->udev, 449 usb_sndintpipe(dev->udev, 450 dev->int_out_endpoint->bEndpointAddress), 451 buf, dev->report_size, 452 iowarrior_write_callback, dev, 453 dev->int_out_endpoint->bInterval); 454 if (copy_from_user(buf, user_buffer, count)) { 455 retval = -EFAULT; 456 goto error; 457 } 458 usb_anchor_urb(int_out_urb, &dev->submitted); 459 retval = usb_submit_urb(int_out_urb, GFP_KERNEL); 460 if (retval) { 461 dev_dbg(&dev->interface->dev, 462 "submit error %d for urb nr.%d\n", 463 retval, atomic_read(&dev->write_busy)); 464 usb_unanchor_urb(int_out_urb); 465 goto error; 466 } 467 /* submit was ok */ 468 retval = count; 469 usb_free_urb(int_out_urb); 470 goto exit; 471 default: 472 /* what do we have here ? An unsupported Product-ID ? */ 473 dev_err(&dev->interface->dev, "%s - not supported for product=0x%x\n", 474 __func__, dev->product_id); 475 retval = -EFAULT; 476 goto exit; 477 } 478 error: 479 kfree(buf); 480 error_no_buffer: 481 usb_free_urb(int_out_urb); 482 error_no_urb: 483 atomic_dec(&dev->write_busy); 484 wake_up_interruptible(&dev->write_wait); 485 exit: 486 mutex_unlock(&dev->mutex); 487 return retval; 488 } 489 490 /* 491 * iowarrior_ioctl 492 */ 493 static long iowarrior_ioctl(struct file *file, unsigned int cmd, 494 unsigned long arg) 495 { 496 struct iowarrior *dev = NULL; 497 __u8 *buffer; 498 __u8 __user *user_buffer; 499 int retval; 500 int io_res; /* checks for bytes read/written and copy_to/from_user results */ 501 502 dev = file->private_data; 503 if (!dev) 504 return -ENODEV; 505 506 buffer = kzalloc(dev->report_size, GFP_KERNEL); 507 if (!buffer) 508 return -ENOMEM; 509 510 mutex_lock(&dev->mutex); 511 512 /* verify that the device wasn't unplugged */ 513 if (!dev->present) { 514 retval = -ENODEV; 515 goto error_out; 516 } 517 518 retval = 0; 519 switch (cmd) { 520 case IOW_WRITE: 521 if (dev->product_id == USB_DEVICE_ID_CODEMERCS_IOW24 || 522 dev->product_id == USB_DEVICE_ID_CODEMERCS_IOW24SAG || 523 dev->product_id == USB_DEVICE_ID_CODEMERCS_IOWPV1 || 524 dev->product_id == USB_DEVICE_ID_CODEMERCS_IOWPV2 || 525 dev->product_id == USB_DEVICE_ID_CODEMERCS_IOW40) { 526 user_buffer = (__u8 __user *)arg; 527 io_res = copy_from_user(buffer, user_buffer, 528 dev->report_size); 529 if (io_res) { 530 retval = -EFAULT; 531 } else { 532 io_res = usb_set_report(dev->interface, 2, 0, 533 buffer, 534 dev->report_size); 535 if (io_res < 0) 536 retval = io_res; 537 } 538 } else { 539 retval = -EINVAL; 540 dev_err(&dev->interface->dev, 541 "ioctl 'IOW_WRITE' is not supported for product=0x%x.\n", 542 dev->product_id); 543 } 544 break; 545 case IOW_READ: 546 user_buffer = (__u8 __user *)arg; 547 io_res = usb_get_report(dev->udev, 548 dev->interface->cur_altsetting, 1, 0, 549 buffer, dev->report_size); 550 if (io_res < 0) 551 retval = io_res; 552 else { 553 io_res = copy_to_user(user_buffer, buffer, dev->report_size); 554 if (io_res) 555 retval = -EFAULT; 556 } 557 break; 558 case IOW_GETINFO: 559 { 560 /* Report available information for the device */ 561 struct iowarrior_info info; 562 /* needed for power consumption */ 563 struct usb_config_descriptor *cfg_descriptor = &dev->udev->actconfig->desc; 564 565 memset(&info, 0, sizeof(info)); 566 /* directly from the descriptor */ 567 info.vendor = le16_to_cpu(dev->udev->descriptor.idVendor); 568 info.product = dev->product_id; 569 info.revision = le16_to_cpu(dev->udev->descriptor.bcdDevice); 570 571 /* 0==UNKNOWN, 1==LOW(usb1.1) ,2=FULL(usb1.1), 3=HIGH(usb2.0) */ 572 info.speed = dev->udev->speed; 573 info.if_num = dev->interface->cur_altsetting->desc.bInterfaceNumber; 574 info.report_size = dev->report_size; 575 576 /* serial number string has been read earlier 8 chars or empty string */ 577 memcpy(info.serial, dev->chip_serial, 578 sizeof(dev->chip_serial)); 579 if (cfg_descriptor == NULL) { 580 info.power = -1; /* no information available */ 581 } else { 582 /* the MaxPower is stored in units of 2mA to make it fit into a byte-value */ 583 info.power = cfg_descriptor->bMaxPower * 2; 584 } 585 io_res = copy_to_user((struct iowarrior_info __user *)arg, &info, 586 sizeof(struct iowarrior_info)); 587 if (io_res) 588 retval = -EFAULT; 589 break; 590 } 591 default: 592 /* return that we did not understand this ioctl call */ 593 retval = -ENOTTY; 594 break; 595 } 596 error_out: 597 /* unlock the device */ 598 mutex_unlock(&dev->mutex); 599 kfree(buffer); 600 return retval; 601 } 602 603 /* 604 * iowarrior_open 605 */ 606 static int iowarrior_open(struct inode *inode, struct file *file) 607 { 608 struct iowarrior *dev = NULL; 609 struct usb_interface *interface; 610 int subminor; 611 int retval = 0; 612 613 subminor = iminor(inode); 614 615 interface = usb_find_interface(&iowarrior_driver, subminor); 616 if (!interface) { 617 pr_err("%s - error, can't find device for minor %d\n", 618 __func__, subminor); 619 return -ENODEV; 620 } 621 622 dev = usb_get_intfdata(interface); 623 if (!dev) 624 return -ENODEV; 625 626 mutex_lock(&dev->mutex); 627 628 /* Only one process can open each device, no sharing. */ 629 if (dev->opened) { 630 retval = -EBUSY; 631 goto out; 632 } 633 634 /* setup interrupt handler for receiving values */ 635 if ((retval = usb_submit_urb(dev->int_in_urb, GFP_KERNEL)) < 0) { 636 dev_err(&interface->dev, "Error %d while submitting URB\n", retval); 637 retval = -EFAULT; 638 goto out; 639 } 640 /* increment our usage count for the driver */ 641 ++dev->opened; 642 /* save our object in the file's private structure */ 643 file->private_data = dev; 644 retval = 0; 645 646 out: 647 mutex_unlock(&dev->mutex); 648 return retval; 649 } 650 651 /* 652 * iowarrior_release 653 */ 654 static int iowarrior_release(struct inode *inode, struct file *file) 655 { 656 struct iowarrior *dev; 657 int retval = 0; 658 659 dev = file->private_data; 660 if (!dev) 661 return -ENODEV; 662 663 /* lock our device */ 664 mutex_lock(&dev->mutex); 665 666 if (dev->opened <= 0) { 667 retval = -ENODEV; /* close called more than once */ 668 mutex_unlock(&dev->mutex); 669 } else { 670 dev->opened = 0; /* we're closing now */ 671 retval = 0; 672 if (dev->present) { 673 /* 674 The device is still connected so we only shutdown 675 pending read-/write-ops. 676 */ 677 usb_kill_urb(dev->int_in_urb); 678 wake_up_interruptible(&dev->read_wait); 679 wake_up_interruptible(&dev->write_wait); 680 mutex_unlock(&dev->mutex); 681 } else { 682 /* The device was unplugged, cleanup resources */ 683 mutex_unlock(&dev->mutex); 684 iowarrior_delete(dev); 685 } 686 } 687 return retval; 688 } 689 690 static __poll_t iowarrior_poll(struct file *file, poll_table * wait) 691 { 692 struct iowarrior *dev = file->private_data; 693 __poll_t mask = 0; 694 695 if (!dev->present) 696 return EPOLLERR | EPOLLHUP; 697 698 poll_wait(file, &dev->read_wait, wait); 699 poll_wait(file, &dev->write_wait, wait); 700 701 if (!dev->present) 702 return EPOLLERR | EPOLLHUP; 703 704 if (read_index(dev) != -1) 705 mask |= EPOLLIN | EPOLLRDNORM; 706 707 if (atomic_read(&dev->write_busy) < MAX_WRITES_IN_FLIGHT) 708 mask |= EPOLLOUT | EPOLLWRNORM; 709 return mask; 710 } 711 712 /* 713 * File operations needed when we register this driver. 714 * This assumes that this driver NEEDS file operations, 715 * of course, which means that the driver is expected 716 * to have a node in the /dev directory. If the USB 717 * device were for a network interface then the driver 718 * would use "struct net_driver" instead, and a serial 719 * device would use "struct tty_driver". 720 */ 721 static const struct file_operations iowarrior_fops = { 722 .owner = THIS_MODULE, 723 .write = iowarrior_write, 724 .read = iowarrior_read, 725 .unlocked_ioctl = iowarrior_ioctl, 726 .open = iowarrior_open, 727 .release = iowarrior_release, 728 .poll = iowarrior_poll, 729 .llseek = noop_llseek, 730 }; 731 732 static char *iowarrior_devnode(const struct device *dev, umode_t *mode) 733 { 734 return kasprintf(GFP_KERNEL, "usb/%s", dev_name(dev)); 735 } 736 737 /* 738 * usb class driver info in order to get a minor number from the usb core, 739 * and to have the device registered with devfs and the driver core 740 */ 741 static struct usb_class_driver iowarrior_class = { 742 .name = "iowarrior%d", 743 .devnode = iowarrior_devnode, 744 .fops = &iowarrior_fops, 745 .minor_base = IOWARRIOR_MINOR_BASE, 746 }; 747 748 /*---------------------------------*/ 749 /* probe and disconnect functions */ 750 /*---------------------------------*/ 751 /* 752 * iowarrior_probe 753 * 754 * Called by the usb core when a new device is connected that it thinks 755 * this driver might be interested in. 756 */ 757 static int iowarrior_probe(struct usb_interface *interface, 758 const struct usb_device_id *id) 759 { 760 struct usb_device *udev = interface_to_usbdev(interface); 761 struct iowarrior *dev = NULL; 762 struct usb_host_interface *iface_desc; 763 int retval = -ENOMEM; 764 int res; 765 int minor; 766 767 /* allocate memory for our device state and initialize it */ 768 dev = kzalloc_obj(struct iowarrior); 769 if (!dev) 770 return retval; 771 772 mutex_init(&dev->mutex); 773 774 atomic_set(&dev->intr_idx, 0); 775 atomic_set(&dev->read_idx, 0); 776 atomic_set(&dev->overflow_flag, 0); 777 init_waitqueue_head(&dev->read_wait); 778 atomic_set(&dev->write_busy, 0); 779 init_waitqueue_head(&dev->write_wait); 780 781 dev->udev = udev; 782 dev->interface = usb_get_intf(interface); 783 784 iface_desc = interface->cur_altsetting; 785 dev->product_id = le16_to_cpu(udev->descriptor.idProduct); 786 787 init_usb_anchor(&dev->submitted); 788 789 res = usb_find_last_int_in_endpoint(iface_desc, &dev->int_in_endpoint); 790 if (res) { 791 dev_err(&interface->dev, "no interrupt-in endpoint found\n"); 792 retval = res; 793 goto error; 794 } 795 796 if ((dev->product_id == USB_DEVICE_ID_CODEMERCS_IOW56) || 797 (dev->product_id == USB_DEVICE_ID_CODEMERCS_IOW56AM) || 798 (dev->product_id == USB_DEVICE_ID_CODEMERCS_IOW28) || 799 (dev->product_id == USB_DEVICE_ID_CODEMERCS_IOW28L) || 800 (dev->product_id == USB_DEVICE_ID_CODEMERCS_IOW100)) { 801 res = usb_find_last_int_out_endpoint(iface_desc, 802 &dev->int_out_endpoint); 803 if (res) { 804 dev_err(&interface->dev, "no interrupt-out endpoint found\n"); 805 retval = res; 806 goto error; 807 } 808 } 809 810 /* we have to check the report_size often, so remember it in the endianness suitable for our machine */ 811 dev->report_size = usb_endpoint_maxp(dev->int_in_endpoint); 812 813 /* 814 * Some devices need the report size to be different than the 815 * endpoint size. 816 */ 817 if (dev->interface->cur_altsetting->desc.bInterfaceNumber == 0) { 818 switch (dev->product_id) { 819 case USB_DEVICE_ID_CODEMERCS_IOW56: 820 case USB_DEVICE_ID_CODEMERCS_IOW56AM: 821 dev->report_size = 7; 822 break; 823 824 case USB_DEVICE_ID_CODEMERCS_IOW28: 825 case USB_DEVICE_ID_CODEMERCS_IOW28L: 826 dev->report_size = 4; 827 break; 828 829 case USB_DEVICE_ID_CODEMERCS_IOW100: 830 dev->report_size = 12; 831 break; 832 } 833 } 834 835 /* create the urb and buffer for reading */ 836 dev->int_in_urb = usb_alloc_urb(0, GFP_KERNEL); 837 if (!dev->int_in_urb) 838 goto error; 839 dev->int_in_buffer = kmalloc(dev->report_size, GFP_KERNEL); 840 if (!dev->int_in_buffer) 841 goto error; 842 usb_fill_int_urb(dev->int_in_urb, dev->udev, 843 usb_rcvintpipe(dev->udev, 844 dev->int_in_endpoint->bEndpointAddress), 845 dev->int_in_buffer, dev->report_size, 846 iowarrior_callback, dev, 847 dev->int_in_endpoint->bInterval); 848 /* create an internal buffer for interrupt data from the device */ 849 dev->read_queue = 850 kmalloc_array(dev->report_size + 1, MAX_INTERRUPT_BUFFER, 851 GFP_KERNEL); 852 if (!dev->read_queue) 853 goto error; 854 /* Get the serial-number of the chip */ 855 memset(dev->chip_serial, 0x00, sizeof(dev->chip_serial)); 856 usb_string(udev, udev->descriptor.iSerialNumber, dev->chip_serial, 857 sizeof(dev->chip_serial)); 858 if (strlen(dev->chip_serial) != 8) 859 memset(dev->chip_serial, 0x00, sizeof(dev->chip_serial)); 860 861 /* Set the idle timeout to 0, if this is interface 0 */ 862 if (dev->interface->cur_altsetting->desc.bInterfaceNumber == 0) { 863 usb_control_msg(udev, usb_sndctrlpipe(udev, 0), 864 0x0A, 865 USB_TYPE_CLASS | USB_RECIP_INTERFACE, 0, 866 0, NULL, 0, USB_CTRL_SET_TIMEOUT); 867 } 868 /* allow device read and ioctl */ 869 dev->present = 1; 870 871 /* we can register the device now, as it is ready */ 872 usb_set_intfdata(interface, dev); 873 874 retval = usb_register_dev(interface, &iowarrior_class); 875 if (retval) { 876 /* something prevented us from registering this driver */ 877 dev_err(&interface->dev, "Not able to get a minor for this device.\n"); 878 goto error; 879 } 880 881 minor = interface->minor; 882 883 /* let the user know what node this device is now attached to */ 884 dev_info(&interface->dev, "IOWarrior product=0x%x, serial=%s interface=%d " 885 "now attached to iowarrior%d\n", dev->product_id, dev->chip_serial, 886 iface_desc->desc.bInterfaceNumber, minor - IOWARRIOR_MINOR_BASE); 887 return retval; 888 889 error: 890 iowarrior_delete(dev); 891 return retval; 892 } 893 894 /* 895 * iowarrior_disconnect 896 * 897 * Called by the usb core when the device is removed from the system. 898 */ 899 static void iowarrior_disconnect(struct usb_interface *interface) 900 { 901 struct iowarrior *dev = usb_get_intfdata(interface); 902 903 usb_deregister_dev(interface, &iowarrior_class); 904 905 mutex_lock(&dev->mutex); 906 907 /* prevent device read, write and ioctl */ 908 dev->present = 0; 909 910 if (dev->opened) { 911 /* There is a process that holds a filedescriptor to the device , 912 so we only shutdown read-/write-ops going on. 913 Deleting the device is postponed until close() was called. 914 */ 915 usb_kill_urb(dev->int_in_urb); 916 usb_kill_anchored_urbs(&dev->submitted); 917 wake_up_interruptible(&dev->read_wait); 918 wake_up_interruptible(&dev->write_wait); 919 mutex_unlock(&dev->mutex); 920 } else { 921 /* no process is using the device, cleanup now */ 922 mutex_unlock(&dev->mutex); 923 iowarrior_delete(dev); 924 } 925 } 926 927 /* usb specific object needed to register this driver with the usb subsystem */ 928 static struct usb_driver iowarrior_driver = { 929 .name = "iowarrior", 930 .probe = iowarrior_probe, 931 .disconnect = iowarrior_disconnect, 932 .id_table = iowarrior_ids, 933 }; 934 935 module_usb_driver(iowarrior_driver); 936