1 /** 2 * drivers/usb/class/usbtmc.c - USB Test & Measurment 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/mutex.h> 29 #include <linux/usb.h> 30 #include <linux/usb/tmc.h> 31 32 33 #define USBTMC_MINOR_BASE 176 34 35 /* 36 * Size of driver internal IO buffer. Must be multiple of 4 and at least as 37 * large as wMaxPacketSize (which is usually 512 bytes). 38 */ 39 #define USBTMC_SIZE_IOBUFFER 2048 40 41 /* Default USB timeout (in milliseconds) */ 42 #define USBTMC_TIMEOUT 10 43 44 /* 45 * Maximum number of read cycles to empty bulk in endpoint during CLEAR and 46 * ABORT_BULK_IN requests. Ends the loop if (for whatever reason) a short 47 * packet is never read. 48 */ 49 #define USBTMC_MAX_READS_TO_CLEAR_BULK_IN 100 50 51 static struct usb_device_id usbtmc_devices[] = { 52 { USB_INTERFACE_INFO(USB_CLASS_APP_SPEC, 3, 0), }, 53 { 0, } /* terminating entry */ 54 }; 55 MODULE_DEVICE_TABLE(usb, usbtmc_devices); 56 57 /* 58 * This structure is the capabilities for the device 59 * See section 4.2.1.8 of the USBTMC specification for details. 60 */ 61 struct usbtmc_dev_capabilities { 62 __u8 interface_capabilities; 63 __u8 device_capabilities; 64 __u8 usb488_interface_capabilities; 65 __u8 usb488_device_capabilities; 66 }; 67 68 /* This structure holds private data for each USBTMC device. One copy is 69 * allocated for each USBTMC device in the driver's probe function. 70 */ 71 struct usbtmc_device_data { 72 const struct usb_device_id *id; 73 struct usb_device *usb_dev; 74 struct usb_interface *intf; 75 76 unsigned int bulk_in; 77 unsigned int bulk_out; 78 79 u8 bTag; 80 u8 bTag_last_write; /* needed for abort */ 81 u8 bTag_last_read; /* needed for abort */ 82 83 /* attributes from the USB TMC spec for this device */ 84 u8 TermChar; 85 bool TermCharEnabled; 86 bool auto_abort; 87 88 struct usbtmc_dev_capabilities capabilities; 89 struct kref kref; 90 struct mutex io_mutex; /* only one i/o function running at a time */ 91 }; 92 #define to_usbtmc_data(d) container_of(d, struct usbtmc_device_data, kref) 93 94 /* Forward declarations */ 95 static struct usb_driver usbtmc_driver; 96 97 static void usbtmc_delete(struct kref *kref) 98 { 99 struct usbtmc_device_data *data = to_usbtmc_data(kref); 100 101 usb_put_dev(data->usb_dev); 102 kfree(data); 103 } 104 105 static int usbtmc_open(struct inode *inode, struct file *filp) 106 { 107 struct usb_interface *intf; 108 struct usbtmc_device_data *data; 109 int retval = -ENODEV; 110 111 intf = usb_find_interface(&usbtmc_driver, iminor(inode)); 112 if (!intf) { 113 printk(KERN_ERR KBUILD_MODNAME 114 ": can not find device for minor %d", iminor(inode)); 115 goto exit; 116 } 117 118 data = usb_get_intfdata(intf); 119 kref_get(&data->kref); 120 121 /* Store pointer in file structure's private data field */ 122 filp->private_data = data; 123 124 exit: 125 return retval; 126 } 127 128 static int usbtmc_release(struct inode *inode, struct file *file) 129 { 130 struct usbtmc_device_data *data = file->private_data; 131 132 kref_put(&data->kref, usbtmc_delete); 133 return 0; 134 } 135 136 static int usbtmc_ioctl_abort_bulk_in(struct usbtmc_device_data *data) 137 { 138 u8 *buffer; 139 struct device *dev; 140 int rv; 141 int n; 142 int actual; 143 struct usb_host_interface *current_setting; 144 int max_size; 145 146 dev = &data->intf->dev; 147 buffer = kmalloc(USBTMC_SIZE_IOBUFFER, GFP_KERNEL); 148 if (!buffer) 149 return -ENOMEM; 150 151 rv = usb_control_msg(data->usb_dev, 152 usb_rcvctrlpipe(data->usb_dev, 0), 153 USBTMC_REQUEST_INITIATE_ABORT_BULK_IN, 154 USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_ENDPOINT, 155 data->bTag_last_read, data->bulk_in, 156 buffer, 2, USBTMC_TIMEOUT); 157 158 if (rv < 0) { 159 dev_err(dev, "usb_control_msg returned %d\n", rv); 160 goto exit; 161 } 162 163 dev_dbg(dev, "INITIATE_ABORT_BULK_IN returned %x\n", buffer[0]); 164 165 if (buffer[0] == USBTMC_STATUS_FAILED) { 166 rv = 0; 167 goto exit; 168 } 169 170 if (buffer[0] != USBTMC_STATUS_SUCCESS) { 171 dev_err(dev, "INITIATE_ABORT_BULK_IN returned %x\n", 172 buffer[0]); 173 rv = -EPERM; 174 goto exit; 175 } 176 177 max_size = 0; 178 current_setting = data->intf->cur_altsetting; 179 for (n = 0; n < current_setting->desc.bNumEndpoints; n++) 180 if (current_setting->endpoint[n].desc.bEndpointAddress == 181 data->bulk_in) 182 max_size = le16_to_cpu(current_setting->endpoint[n]. 183 desc.wMaxPacketSize); 184 185 if (max_size == 0) { 186 dev_err(dev, "Couldn't get wMaxPacketSize\n"); 187 rv = -EPERM; 188 goto exit; 189 } 190 191 dev_dbg(&data->intf->dev, "wMaxPacketSize is %d\n", max_size); 192 193 n = 0; 194 195 do { 196 dev_dbg(dev, "Reading from bulk in EP\n"); 197 198 rv = usb_bulk_msg(data->usb_dev, 199 usb_rcvbulkpipe(data->usb_dev, 200 data->bulk_in), 201 buffer, USBTMC_SIZE_IOBUFFER, 202 &actual, USBTMC_TIMEOUT); 203 204 n++; 205 206 if (rv < 0) { 207 dev_err(dev, "usb_bulk_msg returned %d\n", rv); 208 goto exit; 209 } 210 } while ((actual == max_size) && 211 (n < USBTMC_MAX_READS_TO_CLEAR_BULK_IN)); 212 213 if (actual == max_size) { 214 dev_err(dev, "Couldn't clear device buffer within %d cycles\n", 215 USBTMC_MAX_READS_TO_CLEAR_BULK_IN); 216 rv = -EPERM; 217 goto exit; 218 } 219 220 n = 0; 221 222 usbtmc_abort_bulk_in_status: 223 rv = usb_control_msg(data->usb_dev, 224 usb_rcvctrlpipe(data->usb_dev, 0), 225 USBTMC_REQUEST_CHECK_ABORT_BULK_IN_STATUS, 226 USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_ENDPOINT, 227 0, data->bulk_in, buffer, 0x08, 228 USBTMC_TIMEOUT); 229 230 if (rv < 0) { 231 dev_err(dev, "usb_control_msg returned %d\n", rv); 232 goto exit; 233 } 234 235 dev_dbg(dev, "INITIATE_ABORT_BULK_IN returned %x\n", buffer[0]); 236 237 if (buffer[0] == USBTMC_STATUS_SUCCESS) { 238 rv = 0; 239 goto exit; 240 } 241 242 if (buffer[0] != USBTMC_STATUS_PENDING) { 243 dev_err(dev, "INITIATE_ABORT_BULK_IN returned %x\n", buffer[0]); 244 rv = -EPERM; 245 goto exit; 246 } 247 248 if (buffer[1] == 1) 249 do { 250 dev_dbg(dev, "Reading from bulk in EP\n"); 251 252 rv = usb_bulk_msg(data->usb_dev, 253 usb_rcvbulkpipe(data->usb_dev, 254 data->bulk_in), 255 buffer, USBTMC_SIZE_IOBUFFER, 256 &actual, USBTMC_TIMEOUT); 257 258 n++; 259 260 if (rv < 0) { 261 dev_err(dev, "usb_bulk_msg returned %d\n", rv); 262 goto exit; 263 } 264 } while ((actual = max_size) && 265 (n < USBTMC_MAX_READS_TO_CLEAR_BULK_IN)); 266 267 if (actual == max_size) { 268 dev_err(dev, "Couldn't clear device buffer within %d cycles\n", 269 USBTMC_MAX_READS_TO_CLEAR_BULK_IN); 270 rv = -EPERM; 271 goto exit; 272 } 273 274 goto usbtmc_abort_bulk_in_status; 275 276 exit: 277 kfree(buffer); 278 return rv; 279 280 } 281 282 static int usbtmc_ioctl_abort_bulk_out(struct usbtmc_device_data *data) 283 { 284 struct device *dev; 285 u8 *buffer; 286 int rv; 287 int n; 288 289 dev = &data->intf->dev; 290 291 buffer = kmalloc(8, GFP_KERNEL); 292 if (!buffer) 293 return -ENOMEM; 294 295 rv = usb_control_msg(data->usb_dev, 296 usb_rcvctrlpipe(data->usb_dev, 0), 297 USBTMC_REQUEST_INITIATE_ABORT_BULK_OUT, 298 USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_ENDPOINT, 299 data->bTag_last_write, data->bulk_out, 300 buffer, 2, USBTMC_TIMEOUT); 301 302 if (rv < 0) { 303 dev_err(dev, "usb_control_msg returned %d\n", rv); 304 goto exit; 305 } 306 307 dev_dbg(dev, "INITIATE_ABORT_BULK_OUT returned %x\n", buffer[0]); 308 309 if (buffer[0] != USBTMC_STATUS_SUCCESS) { 310 dev_err(dev, "INITIATE_ABORT_BULK_OUT returned %x\n", 311 buffer[0]); 312 rv = -EPERM; 313 goto exit; 314 } 315 316 n = 0; 317 318 usbtmc_abort_bulk_out_check_status: 319 rv = usb_control_msg(data->usb_dev, 320 usb_rcvctrlpipe(data->usb_dev, 0), 321 USBTMC_REQUEST_CHECK_ABORT_BULK_OUT_STATUS, 322 USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_ENDPOINT, 323 0, data->bulk_out, buffer, 0x08, 324 USBTMC_TIMEOUT); 325 n++; 326 if (rv < 0) { 327 dev_err(dev, "usb_control_msg returned %d\n", rv); 328 goto exit; 329 } 330 331 dev_dbg(dev, "CHECK_ABORT_BULK_OUT returned %x\n", buffer[0]); 332 333 if (buffer[0] == USBTMC_STATUS_SUCCESS) 334 goto usbtmc_abort_bulk_out_clear_halt; 335 336 if ((buffer[0] == USBTMC_STATUS_PENDING) && 337 (n < USBTMC_MAX_READS_TO_CLEAR_BULK_IN)) 338 goto usbtmc_abort_bulk_out_check_status; 339 340 rv = -EPERM; 341 goto exit; 342 343 usbtmc_abort_bulk_out_clear_halt: 344 rv = usb_control_msg(data->usb_dev, 345 usb_sndctrlpipe(data->usb_dev, 0), 346 USB_REQ_CLEAR_FEATURE, 347 USB_DIR_OUT | USB_TYPE_STANDARD | 348 USB_RECIP_ENDPOINT, 349 USB_ENDPOINT_HALT, data->bulk_out, buffer, 350 0, USBTMC_TIMEOUT); 351 352 if (rv < 0) { 353 dev_err(dev, "usb_control_msg returned %d\n", rv); 354 goto exit; 355 } 356 rv = 0; 357 358 exit: 359 kfree(buffer); 360 return rv; 361 } 362 363 static ssize_t usbtmc_read(struct file *filp, char __user *buf, 364 size_t count, loff_t *f_pos) 365 { 366 struct usbtmc_device_data *data; 367 struct device *dev; 368 unsigned long int n_characters; 369 u8 *buffer; 370 int actual; 371 int done; 372 int remaining; 373 int retval; 374 int this_part; 375 376 /* Get pointer to private data structure */ 377 data = filp->private_data; 378 dev = &data->intf->dev; 379 380 buffer = kmalloc(USBTMC_SIZE_IOBUFFER, GFP_KERNEL); 381 if (!buffer) 382 return -ENOMEM; 383 384 mutex_lock(&data->io_mutex); 385 386 remaining = count; 387 done = 0; 388 389 while (remaining > 0) { 390 if (remaining > USBTMC_SIZE_IOBUFFER - 12 - 3) 391 this_part = USBTMC_SIZE_IOBUFFER - 12 - 3; 392 else 393 this_part = remaining; 394 395 /* Setup IO buffer for DEV_DEP_MSG_IN message 396 * Refer to class specs for details 397 */ 398 buffer[0] = 2; 399 buffer[1] = data->bTag; 400 buffer[2] = ~(data->bTag); 401 buffer[3] = 0; /* Reserved */ 402 buffer[4] = (this_part - 12 - 3) & 255; 403 buffer[5] = ((this_part - 12 - 3) >> 8) & 255; 404 buffer[6] = ((this_part - 12 - 3) >> 16) & 255; 405 buffer[7] = ((this_part - 12 - 3) >> 24) & 255; 406 buffer[8] = data->TermCharEnabled * 2; 407 /* Use term character? */ 408 buffer[9] = data->TermChar; 409 buffer[10] = 0; /* Reserved */ 410 buffer[11] = 0; /* Reserved */ 411 412 /* Send bulk URB */ 413 retval = usb_bulk_msg(data->usb_dev, 414 usb_sndbulkpipe(data->usb_dev, 415 data->bulk_out), 416 buffer, 12, &actual, USBTMC_TIMEOUT); 417 418 /* Store bTag (in case we need to abort) */ 419 data->bTag_last_write = data->bTag; 420 421 /* Increment bTag -- and increment again if zero */ 422 data->bTag++; 423 if (!data->bTag) 424 (data->bTag)++; 425 426 if (retval < 0) { 427 dev_err(dev, "usb_bulk_msg returned %d\n", retval); 428 if (data->auto_abort) 429 usbtmc_ioctl_abort_bulk_out(data); 430 goto exit; 431 } 432 433 /* Send bulk URB */ 434 retval = usb_bulk_msg(data->usb_dev, 435 usb_rcvbulkpipe(data->usb_dev, 436 data->bulk_in), 437 buffer, USBTMC_SIZE_IOBUFFER, &actual, 438 USBTMC_TIMEOUT); 439 440 /* Store bTag (in case we need to abort) */ 441 data->bTag_last_read = data->bTag; 442 443 if (retval < 0) { 444 dev_err(dev, "Unable to read data, error %d\n", retval); 445 if (data->auto_abort) 446 usbtmc_ioctl_abort_bulk_in(data); 447 goto exit; 448 } 449 450 /* How many characters did the instrument send? */ 451 n_characters = buffer[4] + 452 (buffer[5] << 8) + 453 (buffer[6] << 16) + 454 (buffer[7] << 24); 455 456 /* Copy buffer to user space */ 457 if (copy_to_user(buf + done, &buffer[12], n_characters)) { 458 /* There must have been an addressing problem */ 459 retval = -EFAULT; 460 goto exit; 461 } 462 463 done += n_characters; 464 if (n_characters < USBTMC_SIZE_IOBUFFER) 465 remaining = 0; 466 } 467 468 /* Update file position value */ 469 *f_pos = *f_pos + done; 470 retval = done; 471 472 exit: 473 mutex_unlock(&data->io_mutex); 474 kfree(buffer); 475 return retval; 476 } 477 478 static ssize_t usbtmc_write(struct file *filp, const char __user *buf, 479 size_t count, loff_t *f_pos) 480 { 481 struct usbtmc_device_data *data; 482 u8 *buffer; 483 int retval; 484 int actual; 485 unsigned long int n_bytes; 486 int remaining; 487 int done; 488 int this_part; 489 490 data = filp->private_data; 491 492 buffer = kmalloc(USBTMC_SIZE_IOBUFFER, GFP_KERNEL); 493 if (!buffer) 494 return -ENOMEM; 495 496 mutex_lock(&data->io_mutex); 497 498 remaining = count; 499 done = 0; 500 501 while (remaining > 0) { 502 if (remaining > USBTMC_SIZE_IOBUFFER - 12) { 503 this_part = USBTMC_SIZE_IOBUFFER - 12; 504 buffer[8] = 0; 505 } else { 506 this_part = remaining; 507 buffer[8] = 1; 508 } 509 510 /* Setup IO buffer for DEV_DEP_MSG_OUT message */ 511 buffer[0] = 1; 512 buffer[1] = data->bTag; 513 buffer[2] = ~(data->bTag); 514 buffer[3] = 0; /* Reserved */ 515 buffer[4] = this_part & 255; 516 buffer[5] = (this_part >> 8) & 255; 517 buffer[6] = (this_part >> 16) & 255; 518 buffer[7] = (this_part >> 24) & 255; 519 /* buffer[8] is set above... */ 520 buffer[9] = 0; /* Reserved */ 521 buffer[10] = 0; /* Reserved */ 522 buffer[11] = 0; /* Reserved */ 523 524 if (copy_from_user(&buffer[12], buf + done, this_part)) { 525 retval = -EFAULT; 526 goto exit; 527 } 528 529 n_bytes = roundup(12 + this_part, 4); 530 memset(buffer + 12 + this_part, 0, n_bytes - (12 + this_part)); 531 532 retval = usb_bulk_msg(data->usb_dev, 533 usb_sndbulkpipe(data->usb_dev, 534 data->bulk_out), 535 buffer, n_bytes, &actual, USBTMC_TIMEOUT); 536 537 data->bTag_last_write = data->bTag; 538 data->bTag++; 539 540 if (!data->bTag) 541 data->bTag++; 542 543 if (retval < 0) { 544 dev_err(&data->intf->dev, 545 "Unable to send data, error %d\n", retval); 546 if (data->auto_abort) 547 usbtmc_ioctl_abort_bulk_out(data); 548 goto exit; 549 } 550 551 remaining -= this_part; 552 done += this_part; 553 } 554 555 retval = count; 556 exit: 557 mutex_unlock(&data->io_mutex); 558 kfree(buffer); 559 return retval; 560 } 561 562 static int usbtmc_ioctl_clear(struct usbtmc_device_data *data) 563 { 564 struct usb_host_interface *current_setting; 565 struct usb_endpoint_descriptor *desc; 566 struct device *dev; 567 u8 *buffer; 568 int rv; 569 int n; 570 int actual; 571 int max_size; 572 573 dev = &data->intf->dev; 574 575 dev_dbg(dev, "Sending INITIATE_CLEAR request\n"); 576 577 buffer = kmalloc(USBTMC_SIZE_IOBUFFER, GFP_KERNEL); 578 if (!buffer) 579 return -ENOMEM; 580 581 rv = usb_control_msg(data->usb_dev, 582 usb_rcvctrlpipe(data->usb_dev, 0), 583 USBTMC_REQUEST_INITIATE_CLEAR, 584 USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE, 585 0, 0, buffer, 1, USBTMC_TIMEOUT); 586 if (rv < 0) { 587 dev_err(dev, "usb_control_msg returned %d\n", rv); 588 goto exit; 589 } 590 591 dev_dbg(dev, "INITIATE_CLEAR returned %x\n", buffer[0]); 592 593 if (buffer[0] != USBTMC_STATUS_SUCCESS) { 594 dev_err(dev, "INITIATE_CLEAR returned %x\n", buffer[0]); 595 rv = -EPERM; 596 goto exit; 597 } 598 599 max_size = 0; 600 current_setting = data->intf->cur_altsetting; 601 for (n = 0; n < current_setting->desc.bNumEndpoints; n++) { 602 desc = ¤t_setting->endpoint[n].desc; 603 if (desc->bEndpointAddress == data->bulk_in) 604 max_size = le16_to_cpu(desc->wMaxPacketSize); 605 } 606 607 if (max_size == 0) { 608 dev_err(dev, "Couldn't get wMaxPacketSize\n"); 609 rv = -EPERM; 610 goto exit; 611 } 612 613 dev_dbg(dev, "wMaxPacketSize is %d\n", max_size); 614 615 n = 0; 616 617 usbtmc_clear_check_status: 618 619 dev_dbg(dev, "Sending CHECK_CLEAR_STATUS request\n"); 620 621 rv = usb_control_msg(data->usb_dev, 622 usb_rcvctrlpipe(data->usb_dev, 0), 623 USBTMC_REQUEST_CHECK_CLEAR_STATUS, 624 USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE, 625 0, 0, buffer, 2, USBTMC_TIMEOUT); 626 if (rv < 0) { 627 dev_err(dev, "usb_control_msg returned %d\n", rv); 628 goto exit; 629 } 630 631 dev_dbg(dev, "CHECK_CLEAR_STATUS returned %x\n", buffer[0]); 632 633 if (buffer[0] == USBTMC_STATUS_SUCCESS) 634 goto usbtmc_clear_bulk_out_halt; 635 636 if (buffer[0] != USBTMC_STATUS_PENDING) { 637 dev_err(dev, "CHECK_CLEAR_STATUS returned %x\n", buffer[0]); 638 rv = -EPERM; 639 goto exit; 640 } 641 642 if (buffer[1] == 1) 643 do { 644 dev_dbg(dev, "Reading from bulk in EP\n"); 645 646 rv = usb_bulk_msg(data->usb_dev, 647 usb_rcvbulkpipe(data->usb_dev, 648 data->bulk_in), 649 buffer, USBTMC_SIZE_IOBUFFER, 650 &actual, USBTMC_TIMEOUT); 651 n++; 652 653 if (rv < 0) { 654 dev_err(dev, "usb_control_msg returned %d\n", 655 rv); 656 goto exit; 657 } 658 } while ((actual == max_size) && 659 (n < USBTMC_MAX_READS_TO_CLEAR_BULK_IN)); 660 661 if (actual == max_size) { 662 dev_err(dev, "Couldn't clear device buffer within %d cycles\n", 663 USBTMC_MAX_READS_TO_CLEAR_BULK_IN); 664 rv = -EPERM; 665 goto exit; 666 } 667 668 goto usbtmc_clear_check_status; 669 670 usbtmc_clear_bulk_out_halt: 671 672 rv = usb_control_msg(data->usb_dev, 673 usb_sndctrlpipe(data->usb_dev, 0), 674 USB_REQ_CLEAR_FEATURE, 675 USB_DIR_OUT | USB_TYPE_STANDARD | 676 USB_RECIP_ENDPOINT, 677 USB_ENDPOINT_HALT, 678 data->bulk_out, buffer, 0, 679 USBTMC_TIMEOUT); 680 if (rv < 0) { 681 dev_err(dev, "usb_control_msg returned %d\n", rv); 682 goto exit; 683 } 684 rv = 0; 685 686 exit: 687 kfree(buffer); 688 return rv; 689 } 690 691 static int usbtmc_ioctl_clear_out_halt(struct usbtmc_device_data *data) 692 { 693 u8 *buffer; 694 int rv; 695 696 buffer = kmalloc(2, GFP_KERNEL); 697 if (!buffer) 698 return -ENOMEM; 699 700 rv = usb_control_msg(data->usb_dev, 701 usb_sndctrlpipe(data->usb_dev, 0), 702 USB_REQ_CLEAR_FEATURE, 703 USB_DIR_OUT | USB_TYPE_STANDARD | 704 USB_RECIP_ENDPOINT, 705 USB_ENDPOINT_HALT, data->bulk_out, 706 buffer, 0, USBTMC_TIMEOUT); 707 708 if (rv < 0) { 709 dev_err(&data->usb_dev->dev, "usb_control_msg returned %d\n", 710 rv); 711 goto exit; 712 } 713 rv = 0; 714 715 exit: 716 kfree(buffer); 717 return rv; 718 } 719 720 static int usbtmc_ioctl_clear_in_halt(struct usbtmc_device_data *data) 721 { 722 u8 *buffer; 723 int rv; 724 725 buffer = kmalloc(2, GFP_KERNEL); 726 if (!buffer) 727 return -ENOMEM; 728 729 rv = usb_control_msg(data->usb_dev, usb_sndctrlpipe(data->usb_dev, 0), 730 USB_REQ_CLEAR_FEATURE, 731 USB_DIR_OUT | USB_TYPE_STANDARD | 732 USB_RECIP_ENDPOINT, 733 USB_ENDPOINT_HALT, data->bulk_in, buffer, 0, 734 USBTMC_TIMEOUT); 735 736 if (rv < 0) { 737 dev_err(&data->usb_dev->dev, "usb_control_msg returned %d\n", 738 rv); 739 goto exit; 740 } 741 rv = 0; 742 743 exit: 744 kfree(buffer); 745 return rv; 746 } 747 748 static int get_capabilities(struct usbtmc_device_data *data) 749 { 750 struct device *dev = &data->usb_dev->dev; 751 char *buffer; 752 int rv; 753 754 buffer = kmalloc(0x18, GFP_KERNEL); 755 if (!buffer) 756 return -ENOMEM; 757 758 rv = usb_control_msg(data->usb_dev, usb_rcvctrlpipe(data->usb_dev, 0), 759 USBTMC_REQUEST_GET_CAPABILITIES, 760 USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE, 761 0, 0, buffer, 0x18, USBTMC_TIMEOUT); 762 if (rv < 0) { 763 dev_err(dev, "usb_control_msg returned %d\n", rv); 764 return rv; 765 } 766 767 dev_dbg(dev, "GET_CAPABILITIES returned %x\n", buffer[0]); 768 dev_dbg(dev, "Interface capabilities are %x\n", buffer[4]); 769 dev_dbg(dev, "Device capabilities are %x\n", buffer[5]); 770 dev_dbg(dev, "USB488 interface capabilities are %x\n", buffer[14]); 771 dev_dbg(dev, "USB488 device capabilities are %x\n", buffer[15]); 772 if (buffer[0] != USBTMC_STATUS_SUCCESS) { 773 dev_err(dev, "GET_CAPABILITIES returned %x\n", buffer[0]); 774 return -EPERM; 775 } 776 777 data->capabilities.interface_capabilities = buffer[4]; 778 data->capabilities.device_capabilities = buffer[5]; 779 data->capabilities.usb488_interface_capabilities = buffer[14]; 780 data->capabilities.usb488_device_capabilities = buffer[15]; 781 782 kfree(buffer); 783 return 0; 784 } 785 786 #define capability_attribute(name) \ 787 static ssize_t show_##name(struct device *dev, \ 788 struct device_attribute *attr, char *buf) \ 789 { \ 790 struct usb_interface *intf = to_usb_interface(dev); \ 791 struct usbtmc_device_data *data = usb_get_intfdata(intf); \ 792 \ 793 return sprintf(buf, "%d\n", data->capabilities.name); \ 794 } \ 795 static DEVICE_ATTR(name, S_IRUGO, show_##name, NULL) 796 797 capability_attribute(interface_capabilities); 798 capability_attribute(device_capabilities); 799 capability_attribute(usb488_interface_capabilities); 800 capability_attribute(usb488_device_capabilities); 801 802 static struct attribute *capability_attrs[] = { 803 &dev_attr_interface_capabilities.attr, 804 &dev_attr_device_capabilities.attr, 805 &dev_attr_usb488_interface_capabilities.attr, 806 &dev_attr_usb488_device_capabilities.attr, 807 NULL, 808 }; 809 810 static struct attribute_group capability_attr_grp = { 811 .attrs = capability_attrs, 812 }; 813 814 static ssize_t show_TermChar(struct device *dev, 815 struct device_attribute *attr, char *buf) 816 { 817 struct usb_interface *intf = to_usb_interface(dev); 818 struct usbtmc_device_data *data = usb_get_intfdata(intf); 819 820 return sprintf(buf, "%c\n", data->TermChar); 821 } 822 823 static ssize_t store_TermChar(struct device *dev, 824 struct device_attribute *attr, 825 const char *buf, size_t count) 826 { 827 struct usb_interface *intf = to_usb_interface(dev); 828 struct usbtmc_device_data *data = usb_get_intfdata(intf); 829 830 if (count < 1) 831 return -EINVAL; 832 data->TermChar = buf[0]; 833 return count; 834 } 835 static DEVICE_ATTR(TermChar, S_IRUGO, show_TermChar, store_TermChar); 836 837 #define data_attribute(name) \ 838 static ssize_t show_##name(struct device *dev, \ 839 struct device_attribute *attr, char *buf) \ 840 { \ 841 struct usb_interface *intf = to_usb_interface(dev); \ 842 struct usbtmc_device_data *data = usb_get_intfdata(intf); \ 843 \ 844 return sprintf(buf, "%d\n", data->name); \ 845 } \ 846 static ssize_t store_##name(struct device *dev, \ 847 struct device_attribute *attr, \ 848 const char *buf, size_t count) \ 849 { \ 850 struct usb_interface *intf = to_usb_interface(dev); \ 851 struct usbtmc_device_data *data = usb_get_intfdata(intf); \ 852 ssize_t result; \ 853 unsigned val; \ 854 \ 855 result = sscanf(buf, "%u\n", &val); \ 856 if (result != 1) \ 857 result = -EINVAL; \ 858 data->name = val; \ 859 if (result < 0) \ 860 return result; \ 861 else \ 862 return count; \ 863 } \ 864 static DEVICE_ATTR(name, S_IRUGO, show_##name, store_##name) 865 866 data_attribute(TermCharEnabled); 867 data_attribute(auto_abort); 868 869 static struct attribute *data_attrs[] = { 870 &dev_attr_TermChar.attr, 871 &dev_attr_TermCharEnabled.attr, 872 &dev_attr_auto_abort.attr, 873 NULL, 874 }; 875 876 static struct attribute_group data_attr_grp = { 877 .attrs = data_attrs, 878 }; 879 880 static int usbtmc_ioctl_indicator_pulse(struct usbtmc_device_data *data) 881 { 882 struct device *dev; 883 u8 *buffer; 884 int rv; 885 886 dev = &data->intf->dev; 887 888 buffer = kmalloc(2, GFP_KERNEL); 889 if (!buffer) 890 return -ENOMEM; 891 892 rv = usb_control_msg(data->usb_dev, 893 usb_rcvctrlpipe(data->usb_dev, 0), 894 USBTMC_REQUEST_INDICATOR_PULSE, 895 USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE, 896 0, 0, buffer, 0x01, USBTMC_TIMEOUT); 897 898 if (rv < 0) { 899 dev_err(dev, "usb_control_msg returned %d\n", rv); 900 goto exit; 901 } 902 903 dev_dbg(dev, "INDICATOR_PULSE returned %x\n", buffer[0]); 904 905 if (buffer[0] != USBTMC_STATUS_SUCCESS) { 906 dev_err(dev, "INDICATOR_PULSE returned %x\n", buffer[0]); 907 rv = -EPERM; 908 goto exit; 909 } 910 rv = 0; 911 912 exit: 913 kfree(buffer); 914 return rv; 915 } 916 917 static long usbtmc_ioctl(struct file *file, unsigned int cmd, unsigned long arg) 918 { 919 struct usbtmc_device_data *data; 920 int retval = -EBADRQC; 921 922 data = file->private_data; 923 mutex_lock(&data->io_mutex); 924 925 switch (cmd) { 926 case USBTMC_IOCTL_CLEAR_OUT_HALT: 927 retval = usbtmc_ioctl_clear_out_halt(data); 928 929 case USBTMC_IOCTL_CLEAR_IN_HALT: 930 retval = usbtmc_ioctl_clear_in_halt(data); 931 932 case USBTMC_IOCTL_INDICATOR_PULSE: 933 retval = usbtmc_ioctl_indicator_pulse(data); 934 935 case USBTMC_IOCTL_CLEAR: 936 retval = usbtmc_ioctl_clear(data); 937 938 case USBTMC_IOCTL_ABORT_BULK_OUT: 939 retval = usbtmc_ioctl_abort_bulk_out(data); 940 941 case USBTMC_IOCTL_ABORT_BULK_IN: 942 retval = usbtmc_ioctl_abort_bulk_in(data); 943 } 944 945 mutex_unlock(&data->io_mutex); 946 return retval; 947 } 948 949 static struct file_operations fops = { 950 .owner = THIS_MODULE, 951 .read = usbtmc_read, 952 .write = usbtmc_write, 953 .open = usbtmc_open, 954 .release = usbtmc_release, 955 .unlocked_ioctl = usbtmc_ioctl, 956 }; 957 958 static struct usb_class_driver usbtmc_class = { 959 .name = "usbtmc%d", 960 .fops = &fops, 961 .minor_base = USBTMC_MINOR_BASE, 962 }; 963 964 965 static int usbtmc_probe(struct usb_interface *intf, 966 const struct usb_device_id *id) 967 { 968 struct usbtmc_device_data *data; 969 struct usb_host_interface *iface_desc; 970 struct usb_endpoint_descriptor *endpoint; 971 int n; 972 int retcode; 973 974 dev_dbg(&intf->dev, "%s called\n", __func__); 975 976 data = kmalloc(sizeof(struct usbtmc_device_data), GFP_KERNEL); 977 if (!data) { 978 dev_err(&intf->dev, "Unable to allocate kernel memory\n"); 979 return -ENOMEM; 980 } 981 982 data->intf = intf; 983 data->id = id; 984 data->usb_dev = usb_get_dev(interface_to_usbdev(intf)); 985 usb_set_intfdata(intf, data); 986 kref_init(&data->kref); 987 mutex_init(&data->io_mutex); 988 989 /* Initialize USBTMC bTag and other fields */ 990 data->bTag = 1; 991 data->TermCharEnabled = 0; 992 data->TermChar = '\n'; 993 994 /* USBTMC devices have only one setting, so use that */ 995 iface_desc = data->intf->cur_altsetting; 996 997 /* Find bulk in endpoint */ 998 for (n = 0; n < iface_desc->desc.bNumEndpoints; n++) { 999 endpoint = &iface_desc->endpoint[n].desc; 1000 1001 if (usb_endpoint_is_bulk_in(endpoint)) { 1002 data->bulk_in = endpoint->bEndpointAddress; 1003 dev_dbg(&intf->dev, "Found bulk in endpoint at %u\n", 1004 data->bulk_in); 1005 break; 1006 } 1007 } 1008 1009 /* Find bulk out endpoint */ 1010 for (n = 0; n < iface_desc->desc.bNumEndpoints; n++) { 1011 endpoint = &iface_desc->endpoint[n].desc; 1012 1013 if (usb_endpoint_is_bulk_out(endpoint)) { 1014 data->bulk_out = endpoint->bEndpointAddress; 1015 dev_dbg(&intf->dev, "Found Bulk out endpoint at %u\n", 1016 data->bulk_out); 1017 break; 1018 } 1019 } 1020 1021 retcode = get_capabilities(data); 1022 if (retcode) 1023 dev_err(&intf->dev, "can't read capabilities\n"); 1024 else 1025 retcode = sysfs_create_group(&intf->dev.kobj, 1026 &capability_attr_grp); 1027 1028 retcode = sysfs_create_group(&intf->dev.kobj, &data_attr_grp); 1029 1030 retcode = usb_register_dev(intf, &usbtmc_class); 1031 if (retcode) { 1032 dev_err(&intf->dev, "Not able to get a minor" 1033 " (base %u, slice default): %d\n", USBTMC_MINOR_BASE, 1034 retcode); 1035 goto error_register; 1036 } 1037 dev_dbg(&intf->dev, "Using minor number %d\n", intf->minor); 1038 1039 return 0; 1040 1041 error_register: 1042 sysfs_remove_group(&intf->dev.kobj, &capability_attr_grp); 1043 sysfs_remove_group(&intf->dev.kobj, &data_attr_grp); 1044 kref_put(&data->kref, usbtmc_delete); 1045 return retcode; 1046 } 1047 1048 static void usbtmc_disconnect(struct usb_interface *intf) 1049 { 1050 struct usbtmc_device_data *data; 1051 1052 dev_dbg(&intf->dev, "usbtmc_disconnect called\n"); 1053 1054 data = usb_get_intfdata(intf); 1055 usb_deregister_dev(intf, &usbtmc_class); 1056 sysfs_remove_group(&intf->dev.kobj, &capability_attr_grp); 1057 sysfs_remove_group(&intf->dev.kobj, &data_attr_grp); 1058 kref_put(&data->kref, usbtmc_delete); 1059 } 1060 1061 static struct usb_driver usbtmc_driver = { 1062 .name = "usbtmc", 1063 .id_table = usbtmc_devices, 1064 .probe = usbtmc_probe, 1065 .disconnect = usbtmc_disconnect 1066 }; 1067 1068 static int __init usbtmc_init(void) 1069 { 1070 int retcode; 1071 1072 retcode = usb_register(&usbtmc_driver); 1073 if (retcode) 1074 printk(KERN_ERR KBUILD_MODNAME": Unable to register driver\n"); 1075 return retcode; 1076 } 1077 module_init(usbtmc_init); 1078 1079 static void __exit usbtmc_exit(void) 1080 { 1081 usb_deregister(&usbtmc_driver); 1082 } 1083 module_exit(usbtmc_exit); 1084 1085 MODULE_LICENSE("GPL"); 1086