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; 280 281 dev = file->private_data; 282 283 /* verify that the device wasn't unplugged */ 284 if (!dev || !dev->present) 285 return -ENODEV; 286 287 dev_dbg(&dev->interface->dev, "minor %d, count = %zd\n", 288 dev->minor, count); 289 290 /* read count must be packet size (+ time stamp) */ 291 if ((count != dev->report_size) 292 && (count != (dev->report_size + 1))) 293 return -EINVAL; 294 295 /* repeat until no buffer overrun in callback handler occur */ 296 do { 297 atomic_set(&dev->overflow_flag, 0); 298 if ((read_idx = read_index(dev)) == -1) { 299 /* queue empty */ 300 if (file->f_flags & O_NONBLOCK) 301 return -EAGAIN; 302 else { 303 //next line will return when there is either new data, or the device is unplugged 304 int r = wait_event_interruptible(dev->read_wait, 305 (!dev->present 306 || (read_idx = 307 read_index 308 (dev)) != 309 -1)); 310 if (r) { 311 //we were interrupted by a signal 312 return -ERESTART; 313 } 314 if (!dev->present) { 315 //The device was unplugged 316 return -ENODEV; 317 } 318 if (read_idx == -1) { 319 // Can this happen ??? 320 return 0; 321 } 322 } 323 } 324 325 offset = read_idx * (dev->report_size + 1); 326 if (copy_to_user(buffer, dev->read_queue + offset, count)) { 327 return -EFAULT; 328 } 329 } while (atomic_read(&dev->overflow_flag)); 330 331 read_idx = ++read_idx == MAX_INTERRUPT_BUFFER ? 0 : read_idx; 332 atomic_set(&dev->read_idx, read_idx); 333 return count; 334 } 335 336 /* 337 * iowarrior_write 338 */ 339 static ssize_t iowarrior_write(struct file *file, 340 const char __user *user_buffer, 341 size_t count, loff_t *ppos) 342 { 343 struct iowarrior *dev; 344 int retval = 0; 345 char *buf = NULL; /* for IOW24 and IOW56 we need a buffer */ 346 struct urb *int_out_urb = NULL; 347 348 dev = file->private_data; 349 350 mutex_lock(&dev->mutex); 351 /* verify that the device wasn't unplugged */ 352 if (!dev->present) { 353 retval = -ENODEV; 354 goto exit; 355 } 356 dev_dbg(&dev->interface->dev, "minor %d, count = %zd\n", 357 dev->minor, count); 358 /* if count is 0 we're already done */ 359 if (count == 0) { 360 retval = 0; 361 goto exit; 362 } 363 /* We only accept full reports */ 364 if (count != dev->report_size) { 365 retval = -EINVAL; 366 goto exit; 367 } 368 switch (dev->product_id) { 369 case USB_DEVICE_ID_CODEMERCS_IOW24: 370 case USB_DEVICE_ID_CODEMERCS_IOW24SAG: 371 case USB_DEVICE_ID_CODEMERCS_IOWPV1: 372 case USB_DEVICE_ID_CODEMERCS_IOWPV2: 373 case USB_DEVICE_ID_CODEMERCS_IOW40: 374 /* IOW24 and IOW40 use a synchronous call */ 375 buf = memdup_user(user_buffer, count); 376 if (IS_ERR(buf)) { 377 retval = PTR_ERR(buf); 378 goto exit; 379 } 380 retval = usb_set_report(dev->interface, 2, 0, buf, count); 381 kfree(buf); 382 goto exit; 383 case USB_DEVICE_ID_CODEMERCS_IOW56: 384 case USB_DEVICE_ID_CODEMERCS_IOW56AM: 385 case USB_DEVICE_ID_CODEMERCS_IOW28: 386 case USB_DEVICE_ID_CODEMERCS_IOW28L: 387 case USB_DEVICE_ID_CODEMERCS_IOW100: 388 /* The IOW56 uses asynchronous IO and more urbs */ 389 if (atomic_read(&dev->write_busy) == MAX_WRITES_IN_FLIGHT) { 390 /* Wait until we are below the limit for submitted urbs */ 391 if (file->f_flags & O_NONBLOCK) { 392 retval = -EAGAIN; 393 goto exit; 394 } else { 395 retval = wait_event_interruptible(dev->write_wait, 396 (!dev->present || (atomic_read (&dev-> write_busy) < MAX_WRITES_IN_FLIGHT))); 397 if (retval) { 398 /* we were interrupted by a signal */ 399 retval = -ERESTART; 400 goto exit; 401 } 402 if (!dev->present) { 403 /* The device was unplugged */ 404 retval = -ENODEV; 405 goto exit; 406 } 407 if (!dev->opened) { 408 /* We were closed while waiting for an URB */ 409 retval = -ENODEV; 410 goto exit; 411 } 412 } 413 } 414 atomic_inc(&dev->write_busy); 415 int_out_urb = usb_alloc_urb(0, GFP_KERNEL); 416 if (!int_out_urb) { 417 retval = -ENOMEM; 418 goto error_no_urb; 419 } 420 buf = usb_alloc_coherent(dev->udev, dev->report_size, 421 GFP_KERNEL, &int_out_urb->transfer_dma); 422 if (!buf) { 423 retval = -ENOMEM; 424 dev_dbg(&dev->interface->dev, 425 "Unable to allocate buffer\n"); 426 goto error_no_buffer; 427 } 428 usb_fill_int_urb(int_out_urb, dev->udev, 429 usb_sndintpipe(dev->udev, 430 dev->int_out_endpoint->bEndpointAddress), 431 buf, dev->report_size, 432 iowarrior_write_callback, dev, 433 dev->int_out_endpoint->bInterval); 434 int_out_urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP; 435 if (copy_from_user(buf, user_buffer, count)) { 436 retval = -EFAULT; 437 goto error; 438 } 439 usb_anchor_urb(int_out_urb, &dev->submitted); 440 retval = usb_submit_urb(int_out_urb, GFP_KERNEL); 441 if (retval) { 442 dev_dbg(&dev->interface->dev, 443 "submit error %d for urb nr.%d\n", 444 retval, atomic_read(&dev->write_busy)); 445 usb_unanchor_urb(int_out_urb); 446 goto error; 447 } 448 /* submit was ok */ 449 retval = count; 450 usb_free_urb(int_out_urb); 451 goto exit; 452 default: 453 /* what do we have here ? An unsupported Product-ID ? */ 454 dev_err(&dev->interface->dev, "%s - not supported for product=0x%x\n", 455 __func__, dev->product_id); 456 retval = -EFAULT; 457 goto exit; 458 } 459 error: 460 usb_free_coherent(dev->udev, dev->report_size, buf, 461 int_out_urb->transfer_dma); 462 error_no_buffer: 463 usb_free_urb(int_out_urb); 464 error_no_urb: 465 atomic_dec(&dev->write_busy); 466 wake_up_interruptible(&dev->write_wait); 467 exit: 468 mutex_unlock(&dev->mutex); 469 return retval; 470 } 471 472 /* 473 * iowarrior_ioctl 474 */ 475 static long iowarrior_ioctl(struct file *file, unsigned int cmd, 476 unsigned long arg) 477 { 478 struct iowarrior *dev = NULL; 479 __u8 *buffer; 480 __u8 __user *user_buffer; 481 int retval; 482 int io_res; /* checks for bytes read/written and copy_to/from_user results */ 483 484 dev = file->private_data; 485 if (!dev) 486 return -ENODEV; 487 488 buffer = kzalloc(dev->report_size, GFP_KERNEL); 489 if (!buffer) 490 return -ENOMEM; 491 492 mutex_lock(&dev->mutex); 493 494 /* verify that the device wasn't unplugged */ 495 if (!dev->present) { 496 retval = -ENODEV; 497 goto error_out; 498 } 499 500 dev_dbg(&dev->interface->dev, "minor %d, cmd 0x%.4x, arg %ld\n", 501 dev->minor, cmd, arg); 502 503 retval = 0; 504 io_res = 0; 505 switch (cmd) { 506 case IOW_WRITE: 507 if (dev->product_id == USB_DEVICE_ID_CODEMERCS_IOW24 || 508 dev->product_id == USB_DEVICE_ID_CODEMERCS_IOW24SAG || 509 dev->product_id == USB_DEVICE_ID_CODEMERCS_IOWPV1 || 510 dev->product_id == USB_DEVICE_ID_CODEMERCS_IOWPV2 || 511 dev->product_id == USB_DEVICE_ID_CODEMERCS_IOW40) { 512 user_buffer = (__u8 __user *)arg; 513 io_res = copy_from_user(buffer, user_buffer, 514 dev->report_size); 515 if (io_res) { 516 retval = -EFAULT; 517 } else { 518 io_res = usb_set_report(dev->interface, 2, 0, 519 buffer, 520 dev->report_size); 521 if (io_res < 0) 522 retval = io_res; 523 } 524 } else { 525 retval = -EINVAL; 526 dev_err(&dev->interface->dev, 527 "ioctl 'IOW_WRITE' is not supported for product=0x%x.\n", 528 dev->product_id); 529 } 530 break; 531 case IOW_READ: 532 user_buffer = (__u8 __user *)arg; 533 io_res = usb_get_report(dev->udev, 534 dev->interface->cur_altsetting, 1, 0, 535 buffer, dev->report_size); 536 if (io_res < 0) 537 retval = io_res; 538 else { 539 io_res = copy_to_user(user_buffer, buffer, dev->report_size); 540 if (io_res) 541 retval = -EFAULT; 542 } 543 break; 544 case IOW_GETINFO: 545 { 546 /* Report available information for the device */ 547 struct iowarrior_info info; 548 /* needed for power consumption */ 549 struct usb_config_descriptor *cfg_descriptor = &dev->udev->actconfig->desc; 550 551 memset(&info, 0, sizeof(info)); 552 /* directly from the descriptor */ 553 info.vendor = le16_to_cpu(dev->udev->descriptor.idVendor); 554 info.product = dev->product_id; 555 info.revision = le16_to_cpu(dev->udev->descriptor.bcdDevice); 556 557 /* 0==UNKNOWN, 1==LOW(usb1.1) ,2=FULL(usb1.1), 3=HIGH(usb2.0) */ 558 info.speed = dev->udev->speed; 559 info.if_num = dev->interface->cur_altsetting->desc.bInterfaceNumber; 560 info.report_size = dev->report_size; 561 562 /* serial number string has been read earlier 8 chars or empty string */ 563 memcpy(info.serial, dev->chip_serial, 564 sizeof(dev->chip_serial)); 565 if (cfg_descriptor == NULL) { 566 info.power = -1; /* no information available */ 567 } else { 568 /* the MaxPower is stored in units of 2mA to make it fit into a byte-value */ 569 info.power = cfg_descriptor->bMaxPower * 2; 570 } 571 io_res = copy_to_user((struct iowarrior_info __user *)arg, &info, 572 sizeof(struct iowarrior_info)); 573 if (io_res) 574 retval = -EFAULT; 575 break; 576 } 577 default: 578 /* return that we did not understand this ioctl call */ 579 retval = -ENOTTY; 580 break; 581 } 582 error_out: 583 /* unlock the device */ 584 mutex_unlock(&dev->mutex); 585 kfree(buffer); 586 return retval; 587 } 588 589 /* 590 * iowarrior_open 591 */ 592 static int iowarrior_open(struct inode *inode, struct file *file) 593 { 594 struct iowarrior *dev = NULL; 595 struct usb_interface *interface; 596 int subminor; 597 int retval = 0; 598 599 subminor = iminor(inode); 600 601 interface = usb_find_interface(&iowarrior_driver, subminor); 602 if (!interface) { 603 pr_err("%s - error, can't find device for minor %d\n", 604 __func__, subminor); 605 return -ENODEV; 606 } 607 608 dev = usb_get_intfdata(interface); 609 if (!dev) 610 return -ENODEV; 611 612 mutex_lock(&dev->mutex); 613 614 /* Only one process can open each device, no sharing. */ 615 if (dev->opened) { 616 retval = -EBUSY; 617 goto out; 618 } 619 620 /* setup interrupt handler for receiving values */ 621 if ((retval = usb_submit_urb(dev->int_in_urb, GFP_KERNEL)) < 0) { 622 dev_err(&interface->dev, "Error %d while submitting URB\n", retval); 623 retval = -EFAULT; 624 goto out; 625 } 626 /* increment our usage count for the driver */ 627 ++dev->opened; 628 /* save our object in the file's private structure */ 629 file->private_data = dev; 630 retval = 0; 631 632 out: 633 mutex_unlock(&dev->mutex); 634 return retval; 635 } 636 637 /* 638 * iowarrior_release 639 */ 640 static int iowarrior_release(struct inode *inode, struct file *file) 641 { 642 struct iowarrior *dev; 643 int retval = 0; 644 645 dev = file->private_data; 646 if (!dev) 647 return -ENODEV; 648 649 dev_dbg(&dev->interface->dev, "minor %d\n", dev->minor); 650 651 /* lock our device */ 652 mutex_lock(&dev->mutex); 653 654 if (dev->opened <= 0) { 655 retval = -ENODEV; /* close called more than once */ 656 mutex_unlock(&dev->mutex); 657 } else { 658 dev->opened = 0; /* we're closing now */ 659 retval = 0; 660 if (dev->present) { 661 /* 662 The device is still connected so we only shutdown 663 pending read-/write-ops. 664 */ 665 usb_kill_urb(dev->int_in_urb); 666 wake_up_interruptible(&dev->read_wait); 667 wake_up_interruptible(&dev->write_wait); 668 mutex_unlock(&dev->mutex); 669 } else { 670 /* The device was unplugged, cleanup resources */ 671 mutex_unlock(&dev->mutex); 672 iowarrior_delete(dev); 673 } 674 } 675 return retval; 676 } 677 678 static __poll_t iowarrior_poll(struct file *file, poll_table * wait) 679 { 680 struct iowarrior *dev = file->private_data; 681 __poll_t mask = 0; 682 683 if (!dev->present) 684 return EPOLLERR | EPOLLHUP; 685 686 poll_wait(file, &dev->read_wait, wait); 687 poll_wait(file, &dev->write_wait, wait); 688 689 if (!dev->present) 690 return EPOLLERR | EPOLLHUP; 691 692 if (read_index(dev) != -1) 693 mask |= EPOLLIN | EPOLLRDNORM; 694 695 if (atomic_read(&dev->write_busy) < MAX_WRITES_IN_FLIGHT) 696 mask |= EPOLLOUT | EPOLLWRNORM; 697 return mask; 698 } 699 700 /* 701 * File operations needed when we register this driver. 702 * This assumes that this driver NEEDS file operations, 703 * of course, which means that the driver is expected 704 * to have a node in the /dev directory. If the USB 705 * device were for a network interface then the driver 706 * would use "struct net_driver" instead, and a serial 707 * device would use "struct tty_driver". 708 */ 709 static const struct file_operations iowarrior_fops = { 710 .owner = THIS_MODULE, 711 .write = iowarrior_write, 712 .read = iowarrior_read, 713 .unlocked_ioctl = iowarrior_ioctl, 714 .open = iowarrior_open, 715 .release = iowarrior_release, 716 .poll = iowarrior_poll, 717 .llseek = noop_llseek, 718 }; 719 720 static char *iowarrior_devnode(struct device *dev, umode_t *mode) 721 { 722 return kasprintf(GFP_KERNEL, "usb/%s", dev_name(dev)); 723 } 724 725 /* 726 * usb class driver info in order to get a minor number from the usb core, 727 * and to have the device registered with devfs and the driver core 728 */ 729 static struct usb_class_driver iowarrior_class = { 730 .name = "iowarrior%d", 731 .devnode = iowarrior_devnode, 732 .fops = &iowarrior_fops, 733 .minor_base = IOWARRIOR_MINOR_BASE, 734 }; 735 736 /*---------------------------------*/ 737 /* probe and disconnect functions */ 738 /*---------------------------------*/ 739 /* 740 * iowarrior_probe 741 * 742 * Called by the usb core when a new device is connected that it thinks 743 * this driver might be interested in. 744 */ 745 static int iowarrior_probe(struct usb_interface *interface, 746 const struct usb_device_id *id) 747 { 748 struct usb_device *udev = interface_to_usbdev(interface); 749 struct iowarrior *dev = NULL; 750 struct usb_host_interface *iface_desc; 751 int retval = -ENOMEM; 752 int res; 753 754 /* allocate memory for our device state and initialize it */ 755 dev = kzalloc(sizeof(struct iowarrior), GFP_KERNEL); 756 if (!dev) 757 return retval; 758 759 mutex_init(&dev->mutex); 760 761 atomic_set(&dev->intr_idx, 0); 762 atomic_set(&dev->read_idx, 0); 763 atomic_set(&dev->overflow_flag, 0); 764 init_waitqueue_head(&dev->read_wait); 765 atomic_set(&dev->write_busy, 0); 766 init_waitqueue_head(&dev->write_wait); 767 768 dev->udev = udev; 769 dev->interface = usb_get_intf(interface); 770 771 iface_desc = interface->cur_altsetting; 772 dev->product_id = le16_to_cpu(udev->descriptor.idProduct); 773 774 init_usb_anchor(&dev->submitted); 775 776 res = usb_find_last_int_in_endpoint(iface_desc, &dev->int_in_endpoint); 777 if (res) { 778 dev_err(&interface->dev, "no interrupt-in endpoint found\n"); 779 retval = res; 780 goto error; 781 } 782 783 if ((dev->product_id == USB_DEVICE_ID_CODEMERCS_IOW56) || 784 (dev->product_id == USB_DEVICE_ID_CODEMERCS_IOW56AM) || 785 (dev->product_id == USB_DEVICE_ID_CODEMERCS_IOW28) || 786 (dev->product_id == USB_DEVICE_ID_CODEMERCS_IOW28L) || 787 (dev->product_id == USB_DEVICE_ID_CODEMERCS_IOW100)) { 788 res = usb_find_last_int_out_endpoint(iface_desc, 789 &dev->int_out_endpoint); 790 if (res) { 791 dev_err(&interface->dev, "no interrupt-out endpoint found\n"); 792 retval = res; 793 goto error; 794 } 795 } 796 797 /* we have to check the report_size often, so remember it in the endianness suitable for our machine */ 798 dev->report_size = usb_endpoint_maxp(dev->int_in_endpoint); 799 800 /* 801 * Some devices need the report size to be different than the 802 * endpoint size. 803 */ 804 if (dev->interface->cur_altsetting->desc.bInterfaceNumber == 0) { 805 switch (dev->product_id) { 806 case USB_DEVICE_ID_CODEMERCS_IOW56: 807 case USB_DEVICE_ID_CODEMERCS_IOW56AM: 808 dev->report_size = 7; 809 break; 810 811 case USB_DEVICE_ID_CODEMERCS_IOW28: 812 case USB_DEVICE_ID_CODEMERCS_IOW28L: 813 dev->report_size = 4; 814 break; 815 816 case USB_DEVICE_ID_CODEMERCS_IOW100: 817 dev->report_size = 13; 818 break; 819 } 820 } 821 822 /* create the urb and buffer for reading */ 823 dev->int_in_urb = usb_alloc_urb(0, GFP_KERNEL); 824 if (!dev->int_in_urb) 825 goto error; 826 dev->int_in_buffer = kmalloc(dev->report_size, GFP_KERNEL); 827 if (!dev->int_in_buffer) 828 goto error; 829 usb_fill_int_urb(dev->int_in_urb, dev->udev, 830 usb_rcvintpipe(dev->udev, 831 dev->int_in_endpoint->bEndpointAddress), 832 dev->int_in_buffer, dev->report_size, 833 iowarrior_callback, dev, 834 dev->int_in_endpoint->bInterval); 835 /* create an internal buffer for interrupt data from the device */ 836 dev->read_queue = 837 kmalloc_array(dev->report_size + 1, MAX_INTERRUPT_BUFFER, 838 GFP_KERNEL); 839 if (!dev->read_queue) 840 goto error; 841 /* Get the serial-number of the chip */ 842 memset(dev->chip_serial, 0x00, sizeof(dev->chip_serial)); 843 usb_string(udev, udev->descriptor.iSerialNumber, dev->chip_serial, 844 sizeof(dev->chip_serial)); 845 if (strlen(dev->chip_serial) != 8) 846 memset(dev->chip_serial, 0x00, sizeof(dev->chip_serial)); 847 848 /* Set the idle timeout to 0, if this is interface 0 */ 849 if (dev->interface->cur_altsetting->desc.bInterfaceNumber == 0) { 850 usb_control_msg(udev, usb_sndctrlpipe(udev, 0), 851 0x0A, 852 USB_TYPE_CLASS | USB_RECIP_INTERFACE, 0, 853 0, NULL, 0, USB_CTRL_SET_TIMEOUT); 854 } 855 /* allow device read and ioctl */ 856 dev->present = 1; 857 858 /* we can register the device now, as it is ready */ 859 usb_set_intfdata(interface, dev); 860 861 retval = usb_register_dev(interface, &iowarrior_class); 862 if (retval) { 863 /* something prevented us from registering this driver */ 864 dev_err(&interface->dev, "Not able to get a minor for this device.\n"); 865 goto error; 866 } 867 868 dev->minor = interface->minor; 869 870 /* let the user know what node this device is now attached to */ 871 dev_info(&interface->dev, "IOWarrior product=0x%x, serial=%s interface=%d " 872 "now attached to iowarrior%d\n", dev->product_id, dev->chip_serial, 873 iface_desc->desc.bInterfaceNumber, dev->minor - IOWARRIOR_MINOR_BASE); 874 return retval; 875 876 error: 877 iowarrior_delete(dev); 878 return retval; 879 } 880 881 /* 882 * iowarrior_disconnect 883 * 884 * Called by the usb core when the device is removed from the system. 885 */ 886 static void iowarrior_disconnect(struct usb_interface *interface) 887 { 888 struct iowarrior *dev = usb_get_intfdata(interface); 889 int minor = dev->minor; 890 891 usb_deregister_dev(interface, &iowarrior_class); 892 893 mutex_lock(&dev->mutex); 894 895 /* prevent device read, write and ioctl */ 896 dev->present = 0; 897 898 if (dev->opened) { 899 /* There is a process that holds a filedescriptor to the device , 900 so we only shutdown read-/write-ops going on. 901 Deleting the device is postponed until close() was called. 902 */ 903 usb_kill_urb(dev->int_in_urb); 904 usb_kill_anchored_urbs(&dev->submitted); 905 wake_up_interruptible(&dev->read_wait); 906 wake_up_interruptible(&dev->write_wait); 907 mutex_unlock(&dev->mutex); 908 } else { 909 /* no process is using the device, cleanup now */ 910 mutex_unlock(&dev->mutex); 911 iowarrior_delete(dev); 912 } 913 914 dev_info(&interface->dev, "I/O-Warror #%d now disconnected\n", 915 minor - IOWARRIOR_MINOR_BASE); 916 } 917 918 /* usb specific object needed to register this driver with the usb subsystem */ 919 static struct usb_driver iowarrior_driver = { 920 .name = "iowarrior", 921 .probe = iowarrior_probe, 922 .disconnect = iowarrior_disconnect, 923 .id_table = iowarrior_ids, 924 }; 925 926 module_usb_driver(iowarrior_driver); 927