1 /* 2 * hdaps.c - driver for IBM's Hard Drive Active Protection System 3 * 4 * Copyright (C) 2005 Robert Love <rml@novell.com> 5 * Copyright (C) 2005 Jesper Juhl <jesper.juhl@gmail.com> 6 * 7 * The HardDisk Active Protection System (hdaps) is present in IBM ThinkPads 8 * starting with the R40, T41, and X40. It provides a basic two-axis 9 * accelerometer and other data, such as the device's temperature. 10 * 11 * This driver is based on the document by Mark A. Smith available at 12 * http://www.almaden.ibm.com/cs/people/marksmith/tpaps.html and a lot of trial 13 * and error. 14 * 15 * This program is free software; you can redistribute it and/or modify it 16 * under the terms of the GNU General Public License v2 as published by the 17 * Free Software Foundation. 18 * 19 * This program is distributed in the hope that it will be useful, but WITHOUT 20 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 21 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for 22 * more details. 23 * 24 * You should have received a copy of the GNU General Public License along with 25 * this program; if not, write to the Free Software Foundation, Inc., 26 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA 27 */ 28 29 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 30 31 #include <linux/delay.h> 32 #include <linux/platform_device.h> 33 #include <linux/input-polldev.h> 34 #include <linux/kernel.h> 35 #include <linux/mutex.h> 36 #include <linux/module.h> 37 #include <linux/timer.h> 38 #include <linux/dmi.h> 39 #include <linux/jiffies.h> 40 #include <linux/io.h> 41 42 #define HDAPS_LOW_PORT 0x1600 /* first port used by hdaps */ 43 #define HDAPS_NR_PORTS 0x30 /* number of ports: 0x1600 - 0x162f */ 44 45 #define HDAPS_PORT_STATE 0x1611 /* device state */ 46 #define HDAPS_PORT_YPOS 0x1612 /* y-axis position */ 47 #define HDAPS_PORT_XPOS 0x1614 /* x-axis position */ 48 #define HDAPS_PORT_TEMP1 0x1616 /* device temperature, in Celsius */ 49 #define HDAPS_PORT_YVAR 0x1617 /* y-axis variance (what is this?) */ 50 #define HDAPS_PORT_XVAR 0x1619 /* x-axis variance (what is this?) */ 51 #define HDAPS_PORT_TEMP2 0x161b /* device temperature (again?) */ 52 #define HDAPS_PORT_UNKNOWN 0x161c /* what is this? */ 53 #define HDAPS_PORT_KMACT 0x161d /* keyboard or mouse activity */ 54 55 #define STATE_FRESH 0x50 /* accelerometer data is fresh */ 56 57 #define KEYBD_MASK 0x20 /* set if keyboard activity */ 58 #define MOUSE_MASK 0x40 /* set if mouse activity */ 59 #define KEYBD_ISSET(n) (!! (n & KEYBD_MASK)) /* keyboard used? */ 60 #define MOUSE_ISSET(n) (!! (n & MOUSE_MASK)) /* mouse used? */ 61 62 #define INIT_TIMEOUT_MSECS 4000 /* wait up to 4s for device init ... */ 63 #define INIT_WAIT_MSECS 200 /* ... in 200ms increments */ 64 65 #define HDAPS_POLL_INTERVAL 50 /* poll for input every 1/20s (50 ms)*/ 66 #define HDAPS_INPUT_FUZZ 4 /* input event threshold */ 67 #define HDAPS_INPUT_FLAT 4 68 69 #define HDAPS_X_AXIS (1 << 0) 70 #define HDAPS_Y_AXIS (1 << 1) 71 #define HDAPS_BOTH_AXES (HDAPS_X_AXIS | HDAPS_Y_AXIS) 72 73 static struct platform_device *pdev; 74 static struct input_polled_dev *hdaps_idev; 75 static unsigned int hdaps_invert; 76 static u8 km_activity; 77 static int rest_x; 78 static int rest_y; 79 80 static DEFINE_MUTEX(hdaps_mtx); 81 82 /* 83 * __get_latch - Get the value from a given port. Callers must hold hdaps_mtx. 84 */ 85 static inline u8 __get_latch(u16 port) 86 { 87 return inb(port) & 0xff; 88 } 89 90 /* 91 * __check_latch - Check a port latch for a given value. Returns zero if the 92 * port contains the given value. Callers must hold hdaps_mtx. 93 */ 94 static inline int __check_latch(u16 port, u8 val) 95 { 96 if (__get_latch(port) == val) 97 return 0; 98 return -EINVAL; 99 } 100 101 /* 102 * __wait_latch - Wait up to 100us for a port latch to get a certain value, 103 * returning zero if the value is obtained. Callers must hold hdaps_mtx. 104 */ 105 static int __wait_latch(u16 port, u8 val) 106 { 107 unsigned int i; 108 109 for (i = 0; i < 20; i++) { 110 if (!__check_latch(port, val)) 111 return 0; 112 udelay(5); 113 } 114 115 return -EIO; 116 } 117 118 /* 119 * __device_refresh - request a refresh from the accelerometer. Does not wait 120 * for refresh to complete. Callers must hold hdaps_mtx. 121 */ 122 static void __device_refresh(void) 123 { 124 udelay(200); 125 if (inb(0x1604) != STATE_FRESH) { 126 outb(0x11, 0x1610); 127 outb(0x01, 0x161f); 128 } 129 } 130 131 /* 132 * __device_refresh_sync - request a synchronous refresh from the 133 * accelerometer. We wait for the refresh to complete. Returns zero if 134 * successful and nonzero on error. Callers must hold hdaps_mtx. 135 */ 136 static int __device_refresh_sync(void) 137 { 138 __device_refresh(); 139 return __wait_latch(0x1604, STATE_FRESH); 140 } 141 142 /* 143 * __device_complete - indicate to the accelerometer that we are done reading 144 * data, and then initiate an async refresh. Callers must hold hdaps_mtx. 145 */ 146 static inline void __device_complete(void) 147 { 148 inb(0x161f); 149 inb(0x1604); 150 __device_refresh(); 151 } 152 153 /* 154 * hdaps_readb_one - reads a byte from a single I/O port, placing the value in 155 * the given pointer. Returns zero on success or a negative error on failure. 156 * Can sleep. 157 */ 158 static int hdaps_readb_one(unsigned int port, u8 *val) 159 { 160 int ret; 161 162 mutex_lock(&hdaps_mtx); 163 164 /* do a sync refresh -- we need to be sure that we read fresh data */ 165 ret = __device_refresh_sync(); 166 if (ret) 167 goto out; 168 169 *val = inb(port); 170 __device_complete(); 171 172 out: 173 mutex_unlock(&hdaps_mtx); 174 return ret; 175 } 176 177 /* __hdaps_read_pair - internal lockless helper for hdaps_read_pair(). */ 178 static int __hdaps_read_pair(unsigned int port1, unsigned int port2, 179 int *x, int *y) 180 { 181 /* do a sync refresh -- we need to be sure that we read fresh data */ 182 if (__device_refresh_sync()) 183 return -EIO; 184 185 *y = inw(port2); 186 *x = inw(port1); 187 km_activity = inb(HDAPS_PORT_KMACT); 188 __device_complete(); 189 190 /* hdaps_invert is a bitvector to negate the axes */ 191 if (hdaps_invert & HDAPS_X_AXIS) 192 *x = -*x; 193 if (hdaps_invert & HDAPS_Y_AXIS) 194 *y = -*y; 195 196 return 0; 197 } 198 199 /* 200 * hdaps_read_pair - reads the values from a pair of ports, placing the values 201 * in the given pointers. Returns zero on success. Can sleep. 202 */ 203 static int hdaps_read_pair(unsigned int port1, unsigned int port2, 204 int *val1, int *val2) 205 { 206 int ret; 207 208 mutex_lock(&hdaps_mtx); 209 ret = __hdaps_read_pair(port1, port2, val1, val2); 210 mutex_unlock(&hdaps_mtx); 211 212 return ret; 213 } 214 215 /* 216 * hdaps_device_init - initialize the accelerometer. Returns zero on success 217 * and negative error code on failure. Can sleep. 218 */ 219 static int hdaps_device_init(void) 220 { 221 int total, ret = -ENXIO; 222 223 mutex_lock(&hdaps_mtx); 224 225 outb(0x13, 0x1610); 226 outb(0x01, 0x161f); 227 if (__wait_latch(0x161f, 0x00)) 228 goto out; 229 230 /* 231 * Most ThinkPads return 0x01. 232 * 233 * Others--namely the R50p, T41p, and T42p--return 0x03. These laptops 234 * have "inverted" axises. 235 * 236 * The 0x02 value occurs when the chip has been previously initialized. 237 */ 238 if (__check_latch(0x1611, 0x03) && 239 __check_latch(0x1611, 0x02) && 240 __check_latch(0x1611, 0x01)) 241 goto out; 242 243 printk(KERN_DEBUG "hdaps: initial latch check good (0x%02x)\n", 244 __get_latch(0x1611)); 245 246 outb(0x17, 0x1610); 247 outb(0x81, 0x1611); 248 outb(0x01, 0x161f); 249 if (__wait_latch(0x161f, 0x00)) 250 goto out; 251 if (__wait_latch(0x1611, 0x00)) 252 goto out; 253 if (__wait_latch(0x1612, 0x60)) 254 goto out; 255 if (__wait_latch(0x1613, 0x00)) 256 goto out; 257 outb(0x14, 0x1610); 258 outb(0x01, 0x1611); 259 outb(0x01, 0x161f); 260 if (__wait_latch(0x161f, 0x00)) 261 goto out; 262 outb(0x10, 0x1610); 263 outb(0xc8, 0x1611); 264 outb(0x00, 0x1612); 265 outb(0x02, 0x1613); 266 outb(0x01, 0x161f); 267 if (__wait_latch(0x161f, 0x00)) 268 goto out; 269 if (__device_refresh_sync()) 270 goto out; 271 if (__wait_latch(0x1611, 0x00)) 272 goto out; 273 274 /* we have done our dance, now let's wait for the applause */ 275 for (total = INIT_TIMEOUT_MSECS; total > 0; total -= INIT_WAIT_MSECS) { 276 int x, y; 277 278 /* a read of the device helps push it into action */ 279 __hdaps_read_pair(HDAPS_PORT_XPOS, HDAPS_PORT_YPOS, &x, &y); 280 if (!__wait_latch(0x1611, 0x02)) { 281 ret = 0; 282 break; 283 } 284 285 msleep(INIT_WAIT_MSECS); 286 } 287 288 out: 289 mutex_unlock(&hdaps_mtx); 290 return ret; 291 } 292 293 294 /* Device model stuff */ 295 296 static int hdaps_probe(struct platform_device *dev) 297 { 298 int ret; 299 300 ret = hdaps_device_init(); 301 if (ret) 302 return ret; 303 304 pr_info("device successfully initialized\n"); 305 return 0; 306 } 307 308 static int hdaps_resume(struct platform_device *dev) 309 { 310 return hdaps_device_init(); 311 } 312 313 static struct platform_driver hdaps_driver = { 314 .probe = hdaps_probe, 315 .resume = hdaps_resume, 316 .driver = { 317 .name = "hdaps", 318 .owner = THIS_MODULE, 319 }, 320 }; 321 322 /* 323 * hdaps_calibrate - Set our "resting" values. Callers must hold hdaps_mtx. 324 */ 325 static void hdaps_calibrate(void) 326 { 327 __hdaps_read_pair(HDAPS_PORT_XPOS, HDAPS_PORT_YPOS, &rest_x, &rest_y); 328 } 329 330 static void hdaps_mousedev_poll(struct input_polled_dev *dev) 331 { 332 struct input_dev *input_dev = dev->input; 333 int x, y; 334 335 mutex_lock(&hdaps_mtx); 336 337 if (__hdaps_read_pair(HDAPS_PORT_XPOS, HDAPS_PORT_YPOS, &x, &y)) 338 goto out; 339 340 input_report_abs(input_dev, ABS_X, x - rest_x); 341 input_report_abs(input_dev, ABS_Y, y - rest_y); 342 input_sync(input_dev); 343 344 out: 345 mutex_unlock(&hdaps_mtx); 346 } 347 348 349 /* Sysfs Files */ 350 351 static ssize_t hdaps_position_show(struct device *dev, 352 struct device_attribute *attr, char *buf) 353 { 354 int ret, x, y; 355 356 ret = hdaps_read_pair(HDAPS_PORT_XPOS, HDAPS_PORT_YPOS, &x, &y); 357 if (ret) 358 return ret; 359 360 return sprintf(buf, "(%d,%d)\n", x, y); 361 } 362 363 static ssize_t hdaps_variance_show(struct device *dev, 364 struct device_attribute *attr, char *buf) 365 { 366 int ret, x, y; 367 368 ret = hdaps_read_pair(HDAPS_PORT_XVAR, HDAPS_PORT_YVAR, &x, &y); 369 if (ret) 370 return ret; 371 372 return sprintf(buf, "(%d,%d)\n", x, y); 373 } 374 375 static ssize_t hdaps_temp1_show(struct device *dev, 376 struct device_attribute *attr, char *buf) 377 { 378 u8 uninitialized_var(temp); 379 int ret; 380 381 ret = hdaps_readb_one(HDAPS_PORT_TEMP1, &temp); 382 if (ret) 383 return ret; 384 385 return sprintf(buf, "%u\n", temp); 386 } 387 388 static ssize_t hdaps_temp2_show(struct device *dev, 389 struct device_attribute *attr, char *buf) 390 { 391 u8 uninitialized_var(temp); 392 int ret; 393 394 ret = hdaps_readb_one(HDAPS_PORT_TEMP2, &temp); 395 if (ret) 396 return ret; 397 398 return sprintf(buf, "%u\n", temp); 399 } 400 401 static ssize_t hdaps_keyboard_activity_show(struct device *dev, 402 struct device_attribute *attr, 403 char *buf) 404 { 405 return sprintf(buf, "%u\n", KEYBD_ISSET(km_activity)); 406 } 407 408 static ssize_t hdaps_mouse_activity_show(struct device *dev, 409 struct device_attribute *attr, 410 char *buf) 411 { 412 return sprintf(buf, "%u\n", MOUSE_ISSET(km_activity)); 413 } 414 415 static ssize_t hdaps_calibrate_show(struct device *dev, 416 struct device_attribute *attr, char *buf) 417 { 418 return sprintf(buf, "(%d,%d)\n", rest_x, rest_y); 419 } 420 421 static ssize_t hdaps_calibrate_store(struct device *dev, 422 struct device_attribute *attr, 423 const char *buf, size_t count) 424 { 425 mutex_lock(&hdaps_mtx); 426 hdaps_calibrate(); 427 mutex_unlock(&hdaps_mtx); 428 429 return count; 430 } 431 432 static ssize_t hdaps_invert_show(struct device *dev, 433 struct device_attribute *attr, char *buf) 434 { 435 return sprintf(buf, "%u\n", hdaps_invert); 436 } 437 438 static ssize_t hdaps_invert_store(struct device *dev, 439 struct device_attribute *attr, 440 const char *buf, size_t count) 441 { 442 int invert; 443 444 if (sscanf(buf, "%d", &invert) != 1 || 445 invert < 0 || invert > HDAPS_BOTH_AXES) 446 return -EINVAL; 447 448 hdaps_invert = invert; 449 hdaps_calibrate(); 450 451 return count; 452 } 453 454 static DEVICE_ATTR(position, 0444, hdaps_position_show, NULL); 455 static DEVICE_ATTR(variance, 0444, hdaps_variance_show, NULL); 456 static DEVICE_ATTR(temp1, 0444, hdaps_temp1_show, NULL); 457 static DEVICE_ATTR(temp2, 0444, hdaps_temp2_show, NULL); 458 static DEVICE_ATTR(keyboard_activity, 0444, hdaps_keyboard_activity_show, NULL); 459 static DEVICE_ATTR(mouse_activity, 0444, hdaps_mouse_activity_show, NULL); 460 static DEVICE_ATTR(calibrate, 0644, hdaps_calibrate_show,hdaps_calibrate_store); 461 static DEVICE_ATTR(invert, 0644, hdaps_invert_show, hdaps_invert_store); 462 463 static struct attribute *hdaps_attributes[] = { 464 &dev_attr_position.attr, 465 &dev_attr_variance.attr, 466 &dev_attr_temp1.attr, 467 &dev_attr_temp2.attr, 468 &dev_attr_keyboard_activity.attr, 469 &dev_attr_mouse_activity.attr, 470 &dev_attr_calibrate.attr, 471 &dev_attr_invert.attr, 472 NULL, 473 }; 474 475 static struct attribute_group hdaps_attribute_group = { 476 .attrs = hdaps_attributes, 477 }; 478 479 480 /* Module stuff */ 481 482 /* hdaps_dmi_match - found a match. return one, short-circuiting the hunt. */ 483 static int __init hdaps_dmi_match(const struct dmi_system_id *id) 484 { 485 pr_info("%s detected\n", id->ident); 486 return 1; 487 } 488 489 /* hdaps_dmi_match_invert - found an inverted match. */ 490 static int __init hdaps_dmi_match_invert(const struct dmi_system_id *id) 491 { 492 hdaps_invert = (unsigned long)id->driver_data; 493 pr_info("inverting axis (%u) readings\n", hdaps_invert); 494 return hdaps_dmi_match(id); 495 } 496 497 #define HDAPS_DMI_MATCH_INVERT(vendor, model, axes) { \ 498 .ident = vendor " " model, \ 499 .callback = hdaps_dmi_match_invert, \ 500 .driver_data = (void *)axes, \ 501 .matches = { \ 502 DMI_MATCH(DMI_BOARD_VENDOR, vendor), \ 503 DMI_MATCH(DMI_PRODUCT_VERSION, model) \ 504 } \ 505 } 506 507 #define HDAPS_DMI_MATCH_NORMAL(vendor, model) \ 508 HDAPS_DMI_MATCH_INVERT(vendor, model, 0) 509 510 /* Note that HDAPS_DMI_MATCH_NORMAL("ThinkPad T42") would match 511 "ThinkPad T42p", so the order of the entries matters. 512 If your ThinkPad is not recognized, please update to latest 513 BIOS. This is especially the case for some R52 ThinkPads. */ 514 static struct dmi_system_id __initdata hdaps_whitelist[] = { 515 HDAPS_DMI_MATCH_INVERT("IBM", "ThinkPad R50p", HDAPS_BOTH_AXES), 516 HDAPS_DMI_MATCH_NORMAL("IBM", "ThinkPad R50"), 517 HDAPS_DMI_MATCH_NORMAL("IBM", "ThinkPad R51"), 518 HDAPS_DMI_MATCH_NORMAL("IBM", "ThinkPad R52"), 519 HDAPS_DMI_MATCH_INVERT("LENOVO", "ThinkPad R61i", HDAPS_BOTH_AXES), 520 HDAPS_DMI_MATCH_INVERT("LENOVO", "ThinkPad R61", HDAPS_BOTH_AXES), 521 HDAPS_DMI_MATCH_INVERT("IBM", "ThinkPad T41p", HDAPS_BOTH_AXES), 522 HDAPS_DMI_MATCH_NORMAL("IBM", "ThinkPad T41"), 523 HDAPS_DMI_MATCH_INVERT("IBM", "ThinkPad T42p", HDAPS_BOTH_AXES), 524 HDAPS_DMI_MATCH_NORMAL("IBM", "ThinkPad T42"), 525 HDAPS_DMI_MATCH_NORMAL("IBM", "ThinkPad T43"), 526 HDAPS_DMI_MATCH_INVERT("LENOVO", "ThinkPad T400", HDAPS_BOTH_AXES), 527 HDAPS_DMI_MATCH_INVERT("LENOVO", "ThinkPad T60", HDAPS_BOTH_AXES), 528 HDAPS_DMI_MATCH_INVERT("LENOVO", "ThinkPad T61p", HDAPS_BOTH_AXES), 529 HDAPS_DMI_MATCH_INVERT("LENOVO", "ThinkPad T61", HDAPS_BOTH_AXES), 530 HDAPS_DMI_MATCH_NORMAL("IBM", "ThinkPad X40"), 531 HDAPS_DMI_MATCH_INVERT("IBM", "ThinkPad X41", HDAPS_Y_AXIS), 532 HDAPS_DMI_MATCH_INVERT("LENOVO", "ThinkPad X60", HDAPS_BOTH_AXES), 533 HDAPS_DMI_MATCH_INVERT("LENOVO", "ThinkPad X61s", HDAPS_BOTH_AXES), 534 HDAPS_DMI_MATCH_INVERT("LENOVO", "ThinkPad X61", HDAPS_BOTH_AXES), 535 HDAPS_DMI_MATCH_NORMAL("IBM", "ThinkPad Z60m"), 536 HDAPS_DMI_MATCH_INVERT("LENOVO", "ThinkPad Z61m", HDAPS_BOTH_AXES), 537 HDAPS_DMI_MATCH_INVERT("LENOVO", "ThinkPad Z61p", HDAPS_BOTH_AXES), 538 { .ident = NULL } 539 }; 540 541 static int __init hdaps_init(void) 542 { 543 struct input_dev *idev; 544 int ret; 545 546 if (!dmi_check_system(hdaps_whitelist)) { 547 pr_warn("supported laptop not found!\n"); 548 ret = -ENODEV; 549 goto out; 550 } 551 552 if (!request_region(HDAPS_LOW_PORT, HDAPS_NR_PORTS, "hdaps")) { 553 ret = -ENXIO; 554 goto out; 555 } 556 557 ret = platform_driver_register(&hdaps_driver); 558 if (ret) 559 goto out_region; 560 561 pdev = platform_device_register_simple("hdaps", -1, NULL, 0); 562 if (IS_ERR(pdev)) { 563 ret = PTR_ERR(pdev); 564 goto out_driver; 565 } 566 567 ret = sysfs_create_group(&pdev->dev.kobj, &hdaps_attribute_group); 568 if (ret) 569 goto out_device; 570 571 hdaps_idev = input_allocate_polled_device(); 572 if (!hdaps_idev) { 573 ret = -ENOMEM; 574 goto out_group; 575 } 576 577 hdaps_idev->poll = hdaps_mousedev_poll; 578 hdaps_idev->poll_interval = HDAPS_POLL_INTERVAL; 579 580 /* initial calibrate for the input device */ 581 hdaps_calibrate(); 582 583 /* initialize the input class */ 584 idev = hdaps_idev->input; 585 idev->name = "hdaps"; 586 idev->phys = "isa1600/input0"; 587 idev->id.bustype = BUS_ISA; 588 idev->dev.parent = &pdev->dev; 589 idev->evbit[0] = BIT_MASK(EV_ABS); 590 input_set_abs_params(idev, ABS_X, 591 -256, 256, HDAPS_INPUT_FUZZ, HDAPS_INPUT_FLAT); 592 input_set_abs_params(idev, ABS_Y, 593 -256, 256, HDAPS_INPUT_FUZZ, HDAPS_INPUT_FLAT); 594 595 ret = input_register_polled_device(hdaps_idev); 596 if (ret) 597 goto out_idev; 598 599 pr_info("driver successfully loaded\n"); 600 return 0; 601 602 out_idev: 603 input_free_polled_device(hdaps_idev); 604 out_group: 605 sysfs_remove_group(&pdev->dev.kobj, &hdaps_attribute_group); 606 out_device: 607 platform_device_unregister(pdev); 608 out_driver: 609 platform_driver_unregister(&hdaps_driver); 610 out_region: 611 release_region(HDAPS_LOW_PORT, HDAPS_NR_PORTS); 612 out: 613 pr_warn("driver init failed (ret=%d)!\n", ret); 614 return ret; 615 } 616 617 static void __exit hdaps_exit(void) 618 { 619 input_unregister_polled_device(hdaps_idev); 620 input_free_polled_device(hdaps_idev); 621 sysfs_remove_group(&pdev->dev.kobj, &hdaps_attribute_group); 622 platform_device_unregister(pdev); 623 platform_driver_unregister(&hdaps_driver); 624 release_region(HDAPS_LOW_PORT, HDAPS_NR_PORTS); 625 626 pr_info("driver unloaded\n"); 627 } 628 629 module_init(hdaps_init); 630 module_exit(hdaps_exit); 631 632 module_param_named(invert, hdaps_invert, int, 0); 633 MODULE_PARM_DESC(invert, "invert data along each axis. 1 invert x-axis, " 634 "2 invert y-axis, 3 invert both axes."); 635 636 MODULE_AUTHOR("Robert Love"); 637 MODULE_DESCRIPTION("IBM Hard Drive Active Protection System (HDAPS) driver"); 638 MODULE_LICENSE("GPL v2"); 639