1 /** 2 * drivers/usb/class/usbtmc.c - USB Test & Measurement class driver 3 * 4 * Copyright (C) 2007 Stefan Kopp, Gechingen, Germany 5 * Copyright (C) 2008 Novell, Inc. 6 * Copyright (C) 2008 Greg Kroah-Hartman <gregkh@suse.de> 7 * 8 * This program is free software; you can redistribute it and/or 9 * modify it under the terms of the GNU General Public License 10 * as published by the Free Software Foundation; either version 2 11 * of the License, or (at your option) any later version. 12 * 13 * This program is distributed in the hope that it will be useful, 14 * but WITHOUT ANY WARRANTY; without even the implied warranty of 15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 16 * GNU General Public License for more details. 17 * 18 * The GNU General Public License is available at 19 * http://www.gnu.org/copyleft/gpl.html. 20 */ 21 22 #include <linux/init.h> 23 #include <linux/module.h> 24 #include <linux/kernel.h> 25 #include <linux/fs.h> 26 #include <linux/uaccess.h> 27 #include <linux/kref.h> 28 #include <linux/slab.h> 29 #include <linux/mutex.h> 30 #include <linux/usb.h> 31 #include <linux/usb/tmc.h> 32 33 34 #define USBTMC_MINOR_BASE 176 35 36 /* 37 * Size of driver internal IO buffer. Must be multiple of 4 and at least as 38 * large as wMaxPacketSize (which is usually 512 bytes). 39 */ 40 #define USBTMC_SIZE_IOBUFFER 2048 41 42 /* Default USB timeout (in milliseconds) */ 43 #define USBTMC_TIMEOUT 5000 44 45 /* 46 * Maximum number of read cycles to empty bulk in endpoint during CLEAR and 47 * ABORT_BULK_IN requests. Ends the loop if (for whatever reason) a short 48 * packet is never read. 49 */ 50 #define USBTMC_MAX_READS_TO_CLEAR_BULK_IN 100 51 52 static const struct usb_device_id usbtmc_devices[] = { 53 { USB_INTERFACE_INFO(USB_CLASS_APP_SPEC, 3, 0), }, 54 { USB_INTERFACE_INFO(USB_CLASS_APP_SPEC, 3, 1), }, 55 { 0, } /* terminating entry */ 56 }; 57 MODULE_DEVICE_TABLE(usb, usbtmc_devices); 58 59 /* 60 * This structure is the capabilities for the device 61 * See section 4.2.1.8 of the USBTMC specification, 62 * and section 4.2.2 of the USBTMC usb488 subclass 63 * specification for details. 64 */ 65 struct usbtmc_dev_capabilities { 66 __u8 interface_capabilities; 67 __u8 device_capabilities; 68 __u8 usb488_interface_capabilities; 69 __u8 usb488_device_capabilities; 70 }; 71 72 /* This structure holds private data for each USBTMC device. One copy is 73 * allocated for each USBTMC device in the driver's probe function. 74 */ 75 struct usbtmc_device_data { 76 const struct usb_device_id *id; 77 struct usb_device *usb_dev; 78 struct usb_interface *intf; 79 80 unsigned int bulk_in; 81 unsigned int bulk_out; 82 83 u8 bTag; 84 u8 bTag_last_write; /* needed for abort */ 85 u8 bTag_last_read; /* needed for abort */ 86 87 /* attributes from the USB TMC spec for this device */ 88 u8 TermChar; 89 bool TermCharEnabled; 90 bool auto_abort; 91 92 bool zombie; /* fd of disconnected device */ 93 94 struct usbtmc_dev_capabilities capabilities; 95 struct kref kref; 96 struct mutex io_mutex; /* only one i/o function running at a time */ 97 }; 98 #define to_usbtmc_data(d) container_of(d, struct usbtmc_device_data, kref) 99 100 /* Forward declarations */ 101 static struct usb_driver usbtmc_driver; 102 103 static void usbtmc_delete(struct kref *kref) 104 { 105 struct usbtmc_device_data *data = to_usbtmc_data(kref); 106 107 usb_put_dev(data->usb_dev); 108 kfree(data); 109 } 110 111 static int usbtmc_open(struct inode *inode, struct file *filp) 112 { 113 struct usb_interface *intf; 114 struct usbtmc_device_data *data; 115 int retval = 0; 116 117 intf = usb_find_interface(&usbtmc_driver, iminor(inode)); 118 if (!intf) { 119 printk(KERN_ERR KBUILD_MODNAME 120 ": can not find device for minor %d", iminor(inode)); 121 retval = -ENODEV; 122 goto exit; 123 } 124 125 data = usb_get_intfdata(intf); 126 kref_get(&data->kref); 127 128 /* Store pointer in file structure's private data field */ 129 filp->private_data = data; 130 131 exit: 132 return retval; 133 } 134 135 static int usbtmc_release(struct inode *inode, struct file *file) 136 { 137 struct usbtmc_device_data *data = file->private_data; 138 139 kref_put(&data->kref, usbtmc_delete); 140 return 0; 141 } 142 143 static int usbtmc_ioctl_abort_bulk_in(struct usbtmc_device_data *data) 144 { 145 u8 *buffer; 146 struct device *dev; 147 int rv; 148 int n; 149 int actual; 150 struct usb_host_interface *current_setting; 151 int max_size; 152 153 dev = &data->intf->dev; 154 buffer = kmalloc(USBTMC_SIZE_IOBUFFER, GFP_KERNEL); 155 if (!buffer) 156 return -ENOMEM; 157 158 rv = usb_control_msg(data->usb_dev, 159 usb_rcvctrlpipe(data->usb_dev, 0), 160 USBTMC_REQUEST_INITIATE_ABORT_BULK_IN, 161 USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_ENDPOINT, 162 data->bTag_last_read, data->bulk_in, 163 buffer, 2, USBTMC_TIMEOUT); 164 165 if (rv < 0) { 166 dev_err(dev, "usb_control_msg returned %d\n", rv); 167 goto exit; 168 } 169 170 dev_dbg(dev, "INITIATE_ABORT_BULK_IN returned %x\n", buffer[0]); 171 172 if (buffer[0] == USBTMC_STATUS_FAILED) { 173 rv = 0; 174 goto exit; 175 } 176 177 if (buffer[0] != USBTMC_STATUS_SUCCESS) { 178 dev_err(dev, "INITIATE_ABORT_BULK_IN returned %x\n", 179 buffer[0]); 180 rv = -EPERM; 181 goto exit; 182 } 183 184 max_size = 0; 185 current_setting = data->intf->cur_altsetting; 186 for (n = 0; n < current_setting->desc.bNumEndpoints; n++) 187 if (current_setting->endpoint[n].desc.bEndpointAddress == 188 data->bulk_in) 189 max_size = usb_endpoint_maxp(¤t_setting->endpoint[n].desc); 190 191 if (max_size == 0) { 192 dev_err(dev, "Couldn't get wMaxPacketSize\n"); 193 rv = -EPERM; 194 goto exit; 195 } 196 197 dev_dbg(&data->intf->dev, "wMaxPacketSize is %d\n", max_size); 198 199 n = 0; 200 201 do { 202 dev_dbg(dev, "Reading from bulk in EP\n"); 203 204 rv = usb_bulk_msg(data->usb_dev, 205 usb_rcvbulkpipe(data->usb_dev, 206 data->bulk_in), 207 buffer, USBTMC_SIZE_IOBUFFER, 208 &actual, USBTMC_TIMEOUT); 209 210 n++; 211 212 if (rv < 0) { 213 dev_err(dev, "usb_bulk_msg returned %d\n", rv); 214 goto exit; 215 } 216 } while ((actual == max_size) && 217 (n < USBTMC_MAX_READS_TO_CLEAR_BULK_IN)); 218 219 if (actual == max_size) { 220 dev_err(dev, "Couldn't clear device buffer within %d cycles\n", 221 USBTMC_MAX_READS_TO_CLEAR_BULK_IN); 222 rv = -EPERM; 223 goto exit; 224 } 225 226 n = 0; 227 228 usbtmc_abort_bulk_in_status: 229 rv = usb_control_msg(data->usb_dev, 230 usb_rcvctrlpipe(data->usb_dev, 0), 231 USBTMC_REQUEST_CHECK_ABORT_BULK_IN_STATUS, 232 USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_ENDPOINT, 233 0, data->bulk_in, buffer, 0x08, 234 USBTMC_TIMEOUT); 235 236 if (rv < 0) { 237 dev_err(dev, "usb_control_msg returned %d\n", rv); 238 goto exit; 239 } 240 241 dev_dbg(dev, "INITIATE_ABORT_BULK_IN returned %x\n", buffer[0]); 242 243 if (buffer[0] == USBTMC_STATUS_SUCCESS) { 244 rv = 0; 245 goto exit; 246 } 247 248 if (buffer[0] != USBTMC_STATUS_PENDING) { 249 dev_err(dev, "INITIATE_ABORT_BULK_IN returned %x\n", buffer[0]); 250 rv = -EPERM; 251 goto exit; 252 } 253 254 if (buffer[1] == 1) 255 do { 256 dev_dbg(dev, "Reading from bulk in EP\n"); 257 258 rv = usb_bulk_msg(data->usb_dev, 259 usb_rcvbulkpipe(data->usb_dev, 260 data->bulk_in), 261 buffer, USBTMC_SIZE_IOBUFFER, 262 &actual, USBTMC_TIMEOUT); 263 264 n++; 265 266 if (rv < 0) { 267 dev_err(dev, "usb_bulk_msg returned %d\n", rv); 268 goto exit; 269 } 270 } while ((actual == max_size) && 271 (n < USBTMC_MAX_READS_TO_CLEAR_BULK_IN)); 272 273 if (actual == max_size) { 274 dev_err(dev, "Couldn't clear device buffer within %d cycles\n", 275 USBTMC_MAX_READS_TO_CLEAR_BULK_IN); 276 rv = -EPERM; 277 goto exit; 278 } 279 280 goto usbtmc_abort_bulk_in_status; 281 282 exit: 283 kfree(buffer); 284 return rv; 285 286 } 287 288 static int usbtmc_ioctl_abort_bulk_out(struct usbtmc_device_data *data) 289 { 290 struct device *dev; 291 u8 *buffer; 292 int rv; 293 int n; 294 295 dev = &data->intf->dev; 296 297 buffer = kmalloc(8, GFP_KERNEL); 298 if (!buffer) 299 return -ENOMEM; 300 301 rv = usb_control_msg(data->usb_dev, 302 usb_rcvctrlpipe(data->usb_dev, 0), 303 USBTMC_REQUEST_INITIATE_ABORT_BULK_OUT, 304 USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_ENDPOINT, 305 data->bTag_last_write, data->bulk_out, 306 buffer, 2, USBTMC_TIMEOUT); 307 308 if (rv < 0) { 309 dev_err(dev, "usb_control_msg returned %d\n", rv); 310 goto exit; 311 } 312 313 dev_dbg(dev, "INITIATE_ABORT_BULK_OUT returned %x\n", buffer[0]); 314 315 if (buffer[0] != USBTMC_STATUS_SUCCESS) { 316 dev_err(dev, "INITIATE_ABORT_BULK_OUT returned %x\n", 317 buffer[0]); 318 rv = -EPERM; 319 goto exit; 320 } 321 322 n = 0; 323 324 usbtmc_abort_bulk_out_check_status: 325 rv = usb_control_msg(data->usb_dev, 326 usb_rcvctrlpipe(data->usb_dev, 0), 327 USBTMC_REQUEST_CHECK_ABORT_BULK_OUT_STATUS, 328 USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_ENDPOINT, 329 0, data->bulk_out, buffer, 0x08, 330 USBTMC_TIMEOUT); 331 n++; 332 if (rv < 0) { 333 dev_err(dev, "usb_control_msg returned %d\n", rv); 334 goto exit; 335 } 336 337 dev_dbg(dev, "CHECK_ABORT_BULK_OUT returned %x\n", buffer[0]); 338 339 if (buffer[0] == USBTMC_STATUS_SUCCESS) 340 goto usbtmc_abort_bulk_out_clear_halt; 341 342 if ((buffer[0] == USBTMC_STATUS_PENDING) && 343 (n < USBTMC_MAX_READS_TO_CLEAR_BULK_IN)) 344 goto usbtmc_abort_bulk_out_check_status; 345 346 rv = -EPERM; 347 goto exit; 348 349 usbtmc_abort_bulk_out_clear_halt: 350 rv = usb_clear_halt(data->usb_dev, 351 usb_sndbulkpipe(data->usb_dev, data->bulk_out)); 352 353 if (rv < 0) { 354 dev_err(dev, "usb_control_msg returned %d\n", rv); 355 goto exit; 356 } 357 rv = 0; 358 359 exit: 360 kfree(buffer); 361 return rv; 362 } 363 364 static ssize_t usbtmc_read(struct file *filp, char __user *buf, 365 size_t count, loff_t *f_pos) 366 { 367 struct usbtmc_device_data *data; 368 struct device *dev; 369 u32 n_characters; 370 u8 *buffer; 371 int actual; 372 size_t done; 373 size_t remaining; 374 int retval; 375 size_t this_part; 376 377 /* Get pointer to private data structure */ 378 data = filp->private_data; 379 dev = &data->intf->dev; 380 381 buffer = kmalloc(USBTMC_SIZE_IOBUFFER, GFP_KERNEL); 382 if (!buffer) 383 return -ENOMEM; 384 385 mutex_lock(&data->io_mutex); 386 if (data->zombie) { 387 retval = -ENODEV; 388 goto exit; 389 } 390 391 remaining = count; 392 done = 0; 393 394 while (remaining > 0) { 395 if (remaining > USBTMC_SIZE_IOBUFFER - 12 - 3) 396 this_part = USBTMC_SIZE_IOBUFFER - 12 - 3; 397 else 398 this_part = remaining; 399 400 /* Setup IO buffer for DEV_DEP_MSG_IN message 401 * Refer to class specs for details 402 */ 403 buffer[0] = 2; 404 buffer[1] = data->bTag; 405 buffer[2] = ~(data->bTag); 406 buffer[3] = 0; /* Reserved */ 407 buffer[4] = (this_part) & 255; 408 buffer[5] = ((this_part) >> 8) & 255; 409 buffer[6] = ((this_part) >> 16) & 255; 410 buffer[7] = ((this_part) >> 24) & 255; 411 buffer[8] = data->TermCharEnabled * 2; 412 /* Use term character? */ 413 buffer[9] = data->TermChar; 414 buffer[10] = 0; /* Reserved */ 415 buffer[11] = 0; /* Reserved */ 416 417 /* Send bulk URB */ 418 retval = usb_bulk_msg(data->usb_dev, 419 usb_sndbulkpipe(data->usb_dev, 420 data->bulk_out), 421 buffer, 12, &actual, USBTMC_TIMEOUT); 422 423 /* Store bTag (in case we need to abort) */ 424 data->bTag_last_write = data->bTag; 425 426 /* Increment bTag -- and increment again if zero */ 427 data->bTag++; 428 if (!data->bTag) 429 (data->bTag)++; 430 431 if (retval < 0) { 432 dev_err(dev, "usb_bulk_msg returned %d\n", retval); 433 if (data->auto_abort) 434 usbtmc_ioctl_abort_bulk_out(data); 435 goto exit; 436 } 437 438 /* Send bulk URB */ 439 retval = usb_bulk_msg(data->usb_dev, 440 usb_rcvbulkpipe(data->usb_dev, 441 data->bulk_in), 442 buffer, USBTMC_SIZE_IOBUFFER, &actual, 443 USBTMC_TIMEOUT); 444 445 /* Store bTag (in case we need to abort) */ 446 data->bTag_last_read = data->bTag; 447 448 if (retval < 0) { 449 dev_err(dev, "Unable to read data, error %d\n", retval); 450 if (data->auto_abort) 451 usbtmc_ioctl_abort_bulk_in(data); 452 goto exit; 453 } 454 455 /* How many characters did the instrument send? */ 456 n_characters = buffer[4] + 457 (buffer[5] << 8) + 458 (buffer[6] << 16) + 459 (buffer[7] << 24); 460 461 /* Ensure the instrument doesn't lie about it */ 462 if(n_characters > actual - 12) { 463 dev_err(dev, "Device lies about message size: %u > %d\n", n_characters, actual - 12); 464 n_characters = actual - 12; 465 } 466 467 /* Ensure the instrument doesn't send more back than requested */ 468 if(n_characters > this_part) { 469 dev_err(dev, "Device returns more than requested: %zu > %zu\n", done + n_characters, done + this_part); 470 n_characters = this_part; 471 } 472 473 /* Bound amount of data received by amount of data requested */ 474 if (n_characters > this_part) 475 n_characters = this_part; 476 477 /* Copy buffer to user space */ 478 if (copy_to_user(buf + done, &buffer[12], n_characters)) { 479 /* There must have been an addressing problem */ 480 retval = -EFAULT; 481 goto exit; 482 } 483 484 done += n_characters; 485 /* Terminate if end-of-message bit received from device */ 486 if ((buffer[8] & 0x01) && (actual >= n_characters + 12)) 487 remaining = 0; 488 else 489 remaining -= n_characters; 490 } 491 492 /* Update file position value */ 493 *f_pos = *f_pos + done; 494 retval = done; 495 496 exit: 497 mutex_unlock(&data->io_mutex); 498 kfree(buffer); 499 return retval; 500 } 501 502 static ssize_t usbtmc_write(struct file *filp, const char __user *buf, 503 size_t count, loff_t *f_pos) 504 { 505 struct usbtmc_device_data *data; 506 u8 *buffer; 507 int retval; 508 int actual; 509 unsigned long int n_bytes; 510 int remaining; 511 int done; 512 int this_part; 513 514 data = filp->private_data; 515 516 buffer = kmalloc(USBTMC_SIZE_IOBUFFER, GFP_KERNEL); 517 if (!buffer) 518 return -ENOMEM; 519 520 mutex_lock(&data->io_mutex); 521 if (data->zombie) { 522 retval = -ENODEV; 523 goto exit; 524 } 525 526 remaining = count; 527 done = 0; 528 529 while (remaining > 0) { 530 if (remaining > USBTMC_SIZE_IOBUFFER - 12) { 531 this_part = USBTMC_SIZE_IOBUFFER - 12; 532 buffer[8] = 0; 533 } else { 534 this_part = remaining; 535 buffer[8] = 1; 536 } 537 538 /* Setup IO buffer for DEV_DEP_MSG_OUT message */ 539 buffer[0] = 1; 540 buffer[1] = data->bTag; 541 buffer[2] = ~(data->bTag); 542 buffer[3] = 0; /* Reserved */ 543 buffer[4] = this_part & 255; 544 buffer[5] = (this_part >> 8) & 255; 545 buffer[6] = (this_part >> 16) & 255; 546 buffer[7] = (this_part >> 24) & 255; 547 /* buffer[8] is set above... */ 548 buffer[9] = 0; /* Reserved */ 549 buffer[10] = 0; /* Reserved */ 550 buffer[11] = 0; /* Reserved */ 551 552 if (copy_from_user(&buffer[12], buf + done, this_part)) { 553 retval = -EFAULT; 554 goto exit; 555 } 556 557 n_bytes = roundup(12 + this_part, 4); 558 memset(buffer + 12 + this_part, 0, n_bytes - (12 + this_part)); 559 560 do { 561 retval = usb_bulk_msg(data->usb_dev, 562 usb_sndbulkpipe(data->usb_dev, 563 data->bulk_out), 564 buffer, n_bytes, 565 &actual, USBTMC_TIMEOUT); 566 if (retval != 0) 567 break; 568 n_bytes -= actual; 569 } while (n_bytes); 570 571 data->bTag_last_write = data->bTag; 572 data->bTag++; 573 574 if (!data->bTag) 575 data->bTag++; 576 577 if (retval < 0) { 578 dev_err(&data->intf->dev, 579 "Unable to send data, error %d\n", retval); 580 if (data->auto_abort) 581 usbtmc_ioctl_abort_bulk_out(data); 582 goto exit; 583 } 584 585 remaining -= this_part; 586 done += this_part; 587 } 588 589 retval = count; 590 exit: 591 mutex_unlock(&data->io_mutex); 592 kfree(buffer); 593 return retval; 594 } 595 596 static int usbtmc_ioctl_clear(struct usbtmc_device_data *data) 597 { 598 struct usb_host_interface *current_setting; 599 struct usb_endpoint_descriptor *desc; 600 struct device *dev; 601 u8 *buffer; 602 int rv; 603 int n; 604 int actual; 605 int max_size; 606 607 dev = &data->intf->dev; 608 609 dev_dbg(dev, "Sending INITIATE_CLEAR request\n"); 610 611 buffer = kmalloc(USBTMC_SIZE_IOBUFFER, GFP_KERNEL); 612 if (!buffer) 613 return -ENOMEM; 614 615 rv = usb_control_msg(data->usb_dev, 616 usb_rcvctrlpipe(data->usb_dev, 0), 617 USBTMC_REQUEST_INITIATE_CLEAR, 618 USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE, 619 0, 0, buffer, 1, USBTMC_TIMEOUT); 620 if (rv < 0) { 621 dev_err(dev, "usb_control_msg returned %d\n", rv); 622 goto exit; 623 } 624 625 dev_dbg(dev, "INITIATE_CLEAR returned %x\n", buffer[0]); 626 627 if (buffer[0] != USBTMC_STATUS_SUCCESS) { 628 dev_err(dev, "INITIATE_CLEAR returned %x\n", buffer[0]); 629 rv = -EPERM; 630 goto exit; 631 } 632 633 max_size = 0; 634 current_setting = data->intf->cur_altsetting; 635 for (n = 0; n < current_setting->desc.bNumEndpoints; n++) { 636 desc = ¤t_setting->endpoint[n].desc; 637 if (desc->bEndpointAddress == data->bulk_in) 638 max_size = usb_endpoint_maxp(desc); 639 } 640 641 if (max_size == 0) { 642 dev_err(dev, "Couldn't get wMaxPacketSize\n"); 643 rv = -EPERM; 644 goto exit; 645 } 646 647 dev_dbg(dev, "wMaxPacketSize is %d\n", max_size); 648 649 n = 0; 650 651 usbtmc_clear_check_status: 652 653 dev_dbg(dev, "Sending CHECK_CLEAR_STATUS request\n"); 654 655 rv = usb_control_msg(data->usb_dev, 656 usb_rcvctrlpipe(data->usb_dev, 0), 657 USBTMC_REQUEST_CHECK_CLEAR_STATUS, 658 USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE, 659 0, 0, buffer, 2, USBTMC_TIMEOUT); 660 if (rv < 0) { 661 dev_err(dev, "usb_control_msg returned %d\n", rv); 662 goto exit; 663 } 664 665 dev_dbg(dev, "CHECK_CLEAR_STATUS returned %x\n", buffer[0]); 666 667 if (buffer[0] == USBTMC_STATUS_SUCCESS) 668 goto usbtmc_clear_bulk_out_halt; 669 670 if (buffer[0] != USBTMC_STATUS_PENDING) { 671 dev_err(dev, "CHECK_CLEAR_STATUS returned %x\n", buffer[0]); 672 rv = -EPERM; 673 goto exit; 674 } 675 676 if (buffer[1] == 1) 677 do { 678 dev_dbg(dev, "Reading from bulk in EP\n"); 679 680 rv = usb_bulk_msg(data->usb_dev, 681 usb_rcvbulkpipe(data->usb_dev, 682 data->bulk_in), 683 buffer, USBTMC_SIZE_IOBUFFER, 684 &actual, USBTMC_TIMEOUT); 685 n++; 686 687 if (rv < 0) { 688 dev_err(dev, "usb_control_msg returned %d\n", 689 rv); 690 goto exit; 691 } 692 } while ((actual == max_size) && 693 (n < USBTMC_MAX_READS_TO_CLEAR_BULK_IN)); 694 695 if (actual == max_size) { 696 dev_err(dev, "Couldn't clear device buffer within %d cycles\n", 697 USBTMC_MAX_READS_TO_CLEAR_BULK_IN); 698 rv = -EPERM; 699 goto exit; 700 } 701 702 goto usbtmc_clear_check_status; 703 704 usbtmc_clear_bulk_out_halt: 705 706 rv = usb_clear_halt(data->usb_dev, 707 usb_sndbulkpipe(data->usb_dev, data->bulk_out)); 708 if (rv < 0) { 709 dev_err(dev, "usb_control_msg returned %d\n", rv); 710 goto exit; 711 } 712 rv = 0; 713 714 exit: 715 kfree(buffer); 716 return rv; 717 } 718 719 static int usbtmc_ioctl_clear_out_halt(struct usbtmc_device_data *data) 720 { 721 u8 *buffer; 722 int rv; 723 724 buffer = kmalloc(2, GFP_KERNEL); 725 if (!buffer) 726 return -ENOMEM; 727 728 rv = usb_clear_halt(data->usb_dev, 729 usb_sndbulkpipe(data->usb_dev, data->bulk_out)); 730 731 if (rv < 0) { 732 dev_err(&data->usb_dev->dev, "usb_control_msg returned %d\n", 733 rv); 734 goto exit; 735 } 736 rv = 0; 737 738 exit: 739 kfree(buffer); 740 return rv; 741 } 742 743 static int usbtmc_ioctl_clear_in_halt(struct usbtmc_device_data *data) 744 { 745 u8 *buffer; 746 int rv; 747 748 buffer = kmalloc(2, GFP_KERNEL); 749 if (!buffer) 750 return -ENOMEM; 751 752 rv = usb_clear_halt(data->usb_dev, 753 usb_rcvbulkpipe(data->usb_dev, data->bulk_in)); 754 755 if (rv < 0) { 756 dev_err(&data->usb_dev->dev, "usb_control_msg returned %d\n", 757 rv); 758 goto exit; 759 } 760 rv = 0; 761 762 exit: 763 kfree(buffer); 764 return rv; 765 } 766 767 static int get_capabilities(struct usbtmc_device_data *data) 768 { 769 struct device *dev = &data->usb_dev->dev; 770 char *buffer; 771 int rv = 0; 772 773 buffer = kmalloc(0x18, GFP_KERNEL); 774 if (!buffer) 775 return -ENOMEM; 776 777 rv = usb_control_msg(data->usb_dev, usb_rcvctrlpipe(data->usb_dev, 0), 778 USBTMC_REQUEST_GET_CAPABILITIES, 779 USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE, 780 0, 0, buffer, 0x18, USBTMC_TIMEOUT); 781 if (rv < 0) { 782 dev_err(dev, "usb_control_msg returned %d\n", rv); 783 goto err_out; 784 } 785 786 dev_dbg(dev, "GET_CAPABILITIES returned %x\n", buffer[0]); 787 if (buffer[0] != USBTMC_STATUS_SUCCESS) { 788 dev_err(dev, "GET_CAPABILITIES returned %x\n", buffer[0]); 789 rv = -EPERM; 790 goto err_out; 791 } 792 dev_dbg(dev, "Interface capabilities are %x\n", buffer[4]); 793 dev_dbg(dev, "Device capabilities are %x\n", buffer[5]); 794 dev_dbg(dev, "USB488 interface capabilities are %x\n", buffer[14]); 795 dev_dbg(dev, "USB488 device capabilities are %x\n", buffer[15]); 796 797 data->capabilities.interface_capabilities = buffer[4]; 798 data->capabilities.device_capabilities = buffer[5]; 799 data->capabilities.usb488_interface_capabilities = buffer[14]; 800 data->capabilities.usb488_device_capabilities = buffer[15]; 801 rv = 0; 802 803 err_out: 804 kfree(buffer); 805 return rv; 806 } 807 808 #define capability_attribute(name) \ 809 static ssize_t show_##name(struct device *dev, \ 810 struct device_attribute *attr, char *buf) \ 811 { \ 812 struct usb_interface *intf = to_usb_interface(dev); \ 813 struct usbtmc_device_data *data = usb_get_intfdata(intf); \ 814 \ 815 return sprintf(buf, "%d\n", data->capabilities.name); \ 816 } \ 817 static DEVICE_ATTR(name, S_IRUGO, show_##name, NULL) 818 819 capability_attribute(interface_capabilities); 820 capability_attribute(device_capabilities); 821 capability_attribute(usb488_interface_capabilities); 822 capability_attribute(usb488_device_capabilities); 823 824 static struct attribute *capability_attrs[] = { 825 &dev_attr_interface_capabilities.attr, 826 &dev_attr_device_capabilities.attr, 827 &dev_attr_usb488_interface_capabilities.attr, 828 &dev_attr_usb488_device_capabilities.attr, 829 NULL, 830 }; 831 832 static struct attribute_group capability_attr_grp = { 833 .attrs = capability_attrs, 834 }; 835 836 static ssize_t show_TermChar(struct device *dev, 837 struct device_attribute *attr, char *buf) 838 { 839 struct usb_interface *intf = to_usb_interface(dev); 840 struct usbtmc_device_data *data = usb_get_intfdata(intf); 841 842 return sprintf(buf, "%c\n", data->TermChar); 843 } 844 845 static ssize_t store_TermChar(struct device *dev, 846 struct device_attribute *attr, 847 const char *buf, size_t count) 848 { 849 struct usb_interface *intf = to_usb_interface(dev); 850 struct usbtmc_device_data *data = usb_get_intfdata(intf); 851 852 if (count < 1) 853 return -EINVAL; 854 data->TermChar = buf[0]; 855 return count; 856 } 857 static DEVICE_ATTR(TermChar, S_IRUGO, show_TermChar, store_TermChar); 858 859 #define data_attribute(name) \ 860 static ssize_t show_##name(struct device *dev, \ 861 struct device_attribute *attr, char *buf) \ 862 { \ 863 struct usb_interface *intf = to_usb_interface(dev); \ 864 struct usbtmc_device_data *data = usb_get_intfdata(intf); \ 865 \ 866 return sprintf(buf, "%d\n", data->name); \ 867 } \ 868 static ssize_t store_##name(struct device *dev, \ 869 struct device_attribute *attr, \ 870 const char *buf, size_t count) \ 871 { \ 872 struct usb_interface *intf = to_usb_interface(dev); \ 873 struct usbtmc_device_data *data = usb_get_intfdata(intf); \ 874 ssize_t result; \ 875 unsigned val; \ 876 \ 877 result = sscanf(buf, "%u\n", &val); \ 878 if (result != 1) \ 879 result = -EINVAL; \ 880 data->name = val; \ 881 if (result < 0) \ 882 return result; \ 883 else \ 884 return count; \ 885 } \ 886 static DEVICE_ATTR(name, S_IRUGO, show_##name, store_##name) 887 888 data_attribute(TermCharEnabled); 889 data_attribute(auto_abort); 890 891 static struct attribute *data_attrs[] = { 892 &dev_attr_TermChar.attr, 893 &dev_attr_TermCharEnabled.attr, 894 &dev_attr_auto_abort.attr, 895 NULL, 896 }; 897 898 static struct attribute_group data_attr_grp = { 899 .attrs = data_attrs, 900 }; 901 902 static int usbtmc_ioctl_indicator_pulse(struct usbtmc_device_data *data) 903 { 904 struct device *dev; 905 u8 *buffer; 906 int rv; 907 908 dev = &data->intf->dev; 909 910 buffer = kmalloc(2, GFP_KERNEL); 911 if (!buffer) 912 return -ENOMEM; 913 914 rv = usb_control_msg(data->usb_dev, 915 usb_rcvctrlpipe(data->usb_dev, 0), 916 USBTMC_REQUEST_INDICATOR_PULSE, 917 USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE, 918 0, 0, buffer, 0x01, USBTMC_TIMEOUT); 919 920 if (rv < 0) { 921 dev_err(dev, "usb_control_msg returned %d\n", rv); 922 goto exit; 923 } 924 925 dev_dbg(dev, "INDICATOR_PULSE returned %x\n", buffer[0]); 926 927 if (buffer[0] != USBTMC_STATUS_SUCCESS) { 928 dev_err(dev, "INDICATOR_PULSE returned %x\n", buffer[0]); 929 rv = -EPERM; 930 goto exit; 931 } 932 rv = 0; 933 934 exit: 935 kfree(buffer); 936 return rv; 937 } 938 939 static long usbtmc_ioctl(struct file *file, unsigned int cmd, unsigned long arg) 940 { 941 struct usbtmc_device_data *data; 942 int retval = -EBADRQC; 943 944 data = file->private_data; 945 mutex_lock(&data->io_mutex); 946 if (data->zombie) { 947 retval = -ENODEV; 948 goto skip_io_on_zombie; 949 } 950 951 switch (cmd) { 952 case USBTMC_IOCTL_CLEAR_OUT_HALT: 953 retval = usbtmc_ioctl_clear_out_halt(data); 954 break; 955 956 case USBTMC_IOCTL_CLEAR_IN_HALT: 957 retval = usbtmc_ioctl_clear_in_halt(data); 958 break; 959 960 case USBTMC_IOCTL_INDICATOR_PULSE: 961 retval = usbtmc_ioctl_indicator_pulse(data); 962 break; 963 964 case USBTMC_IOCTL_CLEAR: 965 retval = usbtmc_ioctl_clear(data); 966 break; 967 968 case USBTMC_IOCTL_ABORT_BULK_OUT: 969 retval = usbtmc_ioctl_abort_bulk_out(data); 970 break; 971 972 case USBTMC_IOCTL_ABORT_BULK_IN: 973 retval = usbtmc_ioctl_abort_bulk_in(data); 974 break; 975 } 976 977 skip_io_on_zombie: 978 mutex_unlock(&data->io_mutex); 979 return retval; 980 } 981 982 static const struct file_operations fops = { 983 .owner = THIS_MODULE, 984 .read = usbtmc_read, 985 .write = usbtmc_write, 986 .open = usbtmc_open, 987 .release = usbtmc_release, 988 .unlocked_ioctl = usbtmc_ioctl, 989 .llseek = default_llseek, 990 }; 991 992 static struct usb_class_driver usbtmc_class = { 993 .name = "usbtmc%d", 994 .fops = &fops, 995 .minor_base = USBTMC_MINOR_BASE, 996 }; 997 998 999 static int usbtmc_probe(struct usb_interface *intf, 1000 const struct usb_device_id *id) 1001 { 1002 struct usbtmc_device_data *data; 1003 struct usb_host_interface *iface_desc; 1004 struct usb_endpoint_descriptor *endpoint; 1005 int n; 1006 int retcode; 1007 1008 dev_dbg(&intf->dev, "%s called\n", __func__); 1009 1010 data = kmalloc(sizeof(struct usbtmc_device_data), GFP_KERNEL); 1011 if (!data) { 1012 dev_err(&intf->dev, "Unable to allocate kernel memory\n"); 1013 return -ENOMEM; 1014 } 1015 1016 data->intf = intf; 1017 data->id = id; 1018 data->usb_dev = usb_get_dev(interface_to_usbdev(intf)); 1019 usb_set_intfdata(intf, data); 1020 kref_init(&data->kref); 1021 mutex_init(&data->io_mutex); 1022 data->zombie = 0; 1023 1024 /* Initialize USBTMC bTag and other fields */ 1025 data->bTag = 1; 1026 data->TermCharEnabled = 0; 1027 data->TermChar = '\n'; 1028 1029 /* USBTMC devices have only one setting, so use that */ 1030 iface_desc = data->intf->cur_altsetting; 1031 1032 /* Find bulk in endpoint */ 1033 for (n = 0; n < iface_desc->desc.bNumEndpoints; n++) { 1034 endpoint = &iface_desc->endpoint[n].desc; 1035 1036 if (usb_endpoint_is_bulk_in(endpoint)) { 1037 data->bulk_in = endpoint->bEndpointAddress; 1038 dev_dbg(&intf->dev, "Found bulk in endpoint at %u\n", 1039 data->bulk_in); 1040 break; 1041 } 1042 } 1043 1044 /* Find bulk out endpoint */ 1045 for (n = 0; n < iface_desc->desc.bNumEndpoints; n++) { 1046 endpoint = &iface_desc->endpoint[n].desc; 1047 1048 if (usb_endpoint_is_bulk_out(endpoint)) { 1049 data->bulk_out = endpoint->bEndpointAddress; 1050 dev_dbg(&intf->dev, "Found Bulk out endpoint at %u\n", 1051 data->bulk_out); 1052 break; 1053 } 1054 } 1055 1056 retcode = get_capabilities(data); 1057 if (retcode) 1058 dev_err(&intf->dev, "can't read capabilities\n"); 1059 else 1060 retcode = sysfs_create_group(&intf->dev.kobj, 1061 &capability_attr_grp); 1062 1063 retcode = sysfs_create_group(&intf->dev.kobj, &data_attr_grp); 1064 1065 retcode = usb_register_dev(intf, &usbtmc_class); 1066 if (retcode) { 1067 dev_err(&intf->dev, "Not able to get a minor" 1068 " (base %u, slice default): %d\n", USBTMC_MINOR_BASE, 1069 retcode); 1070 goto error_register; 1071 } 1072 dev_dbg(&intf->dev, "Using minor number %d\n", intf->minor); 1073 1074 return 0; 1075 1076 error_register: 1077 sysfs_remove_group(&intf->dev.kobj, &capability_attr_grp); 1078 sysfs_remove_group(&intf->dev.kobj, &data_attr_grp); 1079 kref_put(&data->kref, usbtmc_delete); 1080 return retcode; 1081 } 1082 1083 static void usbtmc_disconnect(struct usb_interface *intf) 1084 { 1085 struct usbtmc_device_data *data; 1086 1087 dev_dbg(&intf->dev, "usbtmc_disconnect called\n"); 1088 1089 data = usb_get_intfdata(intf); 1090 usb_deregister_dev(intf, &usbtmc_class); 1091 sysfs_remove_group(&intf->dev.kobj, &capability_attr_grp); 1092 sysfs_remove_group(&intf->dev.kobj, &data_attr_grp); 1093 mutex_lock(&data->io_mutex); 1094 data->zombie = 1; 1095 mutex_unlock(&data->io_mutex); 1096 kref_put(&data->kref, usbtmc_delete); 1097 } 1098 1099 static int usbtmc_suspend(struct usb_interface *intf, pm_message_t message) 1100 { 1101 /* this driver does not have pending URBs */ 1102 return 0; 1103 } 1104 1105 static int usbtmc_resume(struct usb_interface *intf) 1106 { 1107 return 0; 1108 } 1109 1110 static struct usb_driver usbtmc_driver = { 1111 .name = "usbtmc", 1112 .id_table = usbtmc_devices, 1113 .probe = usbtmc_probe, 1114 .disconnect = usbtmc_disconnect, 1115 .suspend = usbtmc_suspend, 1116 .resume = usbtmc_resume, 1117 }; 1118 1119 module_usb_driver(usbtmc_driver); 1120 1121 MODULE_LICENSE("GPL"); 1122