1 /* 2 * CMOS/NV-RAM driver for Linux 3 * 4 * Copyright (C) 1997 Roman Hodek <Roman.Hodek@informatik.uni-erlangen.de> 5 * idea by and with help from Richard Jelinek <rj@suse.de> 6 * Portions copyright (c) 2001,2002 Sun Microsystems (thockin@sun.com) 7 * 8 * This driver allows you to access the contents of the non-volatile memory in 9 * the mc146818rtc.h real-time clock. This chip is built into all PCs and into 10 * many Atari machines. In the former it's called "CMOS-RAM", in the latter 11 * "NVRAM" (NV stands for non-volatile). 12 * 13 * The data are supplied as a (seekable) character device, /dev/nvram. The 14 * size of this file is dependent on the controller. The usual size is 114, 15 * the number of freely available bytes in the memory (i.e., not used by the 16 * RTC itself). 17 * 18 * Checksums over the NVRAM contents are managed by this driver. In case of a 19 * bad checksum, reads and writes return -EIO. The checksum can be initialized 20 * to a sane state either by ioctl(NVRAM_INIT) (clear whole NVRAM) or 21 * ioctl(NVRAM_SETCKS) (doesn't change contents, just makes checksum valid 22 * again; use with care!) 23 * 24 * This file also provides some functions for other parts of the kernel that 25 * want to access the NVRAM: nvram_{read,write,check_checksum,set_checksum}. 26 * Obviously this can be used only if this driver is always configured into 27 * the kernel and is not a module. Since the functions are used by some Atari 28 * drivers, this is the case on the Atari. 29 * 30 * 31 * 1.1 Cesar Barros: SMP locking fixes 32 * added changelog 33 * 1.2 Erik Gilling: Cobalt Networks support 34 * Tim Hockin: general cleanup, Cobalt support 35 * 1.3 Wim Van Sebroeck: convert PRINT_PROC to seq_file 36 */ 37 38 #define NVRAM_VERSION "1.3" 39 40 #include <linux/module.h> 41 #include <linux/smp_lock.h> 42 #include <linux/nvram.h> 43 44 #define PC 1 45 #define ATARI 2 46 47 /* select machine configuration */ 48 #if defined(CONFIG_ATARI) 49 # define MACH ATARI 50 #elif defined(__i386__) || defined(__x86_64__) || defined(__arm__) /* and ?? */ 51 # define MACH PC 52 #else 53 # error Cannot build nvram driver for this machine configuration. 54 #endif 55 56 #if MACH == PC 57 58 /* RTC in a PC */ 59 #define CHECK_DRIVER_INIT() 1 60 61 /* On PCs, the checksum is built only over bytes 2..31 */ 62 #define PC_CKS_RANGE_START 2 63 #define PC_CKS_RANGE_END 31 64 #define PC_CKS_LOC 32 65 #define NVRAM_BYTES (128-NVRAM_FIRST_BYTE) 66 67 #define mach_check_checksum pc_check_checksum 68 #define mach_set_checksum pc_set_checksum 69 #define mach_proc_infos pc_proc_infos 70 71 #endif 72 73 #if MACH == ATARI 74 75 /* Special parameters for RTC in Atari machines */ 76 #include <asm/atarihw.h> 77 #include <asm/atariints.h> 78 #define RTC_PORT(x) (TT_RTC_BAS + 2*(x)) 79 #define CHECK_DRIVER_INIT() (MACH_IS_ATARI && ATARIHW_PRESENT(TT_CLK)) 80 81 #define NVRAM_BYTES 50 82 83 /* On Ataris, the checksum is over all bytes except the checksum bytes 84 * themselves; these are at the very end */ 85 #define ATARI_CKS_RANGE_START 0 86 #define ATARI_CKS_RANGE_END 47 87 #define ATARI_CKS_LOC 48 88 89 #define mach_check_checksum atari_check_checksum 90 #define mach_set_checksum atari_set_checksum 91 #define mach_proc_infos atari_proc_infos 92 93 #endif 94 95 /* Note that *all* calls to CMOS_READ and CMOS_WRITE must be done with 96 * rtc_lock held. Due to the index-port/data-port design of the RTC, we 97 * don't want two different things trying to get to it at once. (e.g. the 98 * periodic 11 min sync from time.c vs. this driver.) 99 */ 100 101 #include <linux/types.h> 102 #include <linux/errno.h> 103 #include <linux/miscdevice.h> 104 #include <linux/slab.h> 105 #include <linux/ioport.h> 106 #include <linux/fcntl.h> 107 #include <linux/mc146818rtc.h> 108 #include <linux/init.h> 109 #include <linux/proc_fs.h> 110 #include <linux/seq_file.h> 111 #include <linux/spinlock.h> 112 #include <linux/io.h> 113 #include <linux/uaccess.h> 114 115 #include <asm/system.h> 116 117 static DEFINE_SPINLOCK(nvram_state_lock); 118 static int nvram_open_cnt; /* #times opened */ 119 static int nvram_open_mode; /* special open modes */ 120 #define NVRAM_WRITE 1 /* opened for writing (exclusive) */ 121 #define NVRAM_EXCL 2 /* opened with O_EXCL */ 122 123 static int mach_check_checksum(void); 124 static void mach_set_checksum(void); 125 126 #ifdef CONFIG_PROC_FS 127 static void mach_proc_infos(unsigned char *contents, struct seq_file *seq, 128 void *offset); 129 #endif 130 131 /* 132 * These functions are provided to be called internally or by other parts of 133 * the kernel. It's up to the caller to ensure correct checksum before reading 134 * or after writing (needs to be done only once). 135 * 136 * It is worth noting that these functions all access bytes of general 137 * purpose memory in the NVRAM - that is to say, they all add the 138 * NVRAM_FIRST_BYTE offset. Pass them offsets into NVRAM as if you did not 139 * know about the RTC cruft. 140 */ 141 142 unsigned char __nvram_read_byte(int i) 143 { 144 return CMOS_READ(NVRAM_FIRST_BYTE + i); 145 } 146 EXPORT_SYMBOL(__nvram_read_byte); 147 148 unsigned char nvram_read_byte(int i) 149 { 150 unsigned long flags; 151 unsigned char c; 152 153 spin_lock_irqsave(&rtc_lock, flags); 154 c = __nvram_read_byte(i); 155 spin_unlock_irqrestore(&rtc_lock, flags); 156 return c; 157 } 158 EXPORT_SYMBOL(nvram_read_byte); 159 160 /* This races nicely with trying to read with checksum checking (nvram_read) */ 161 void __nvram_write_byte(unsigned char c, int i) 162 { 163 CMOS_WRITE(c, NVRAM_FIRST_BYTE + i); 164 } 165 EXPORT_SYMBOL(__nvram_write_byte); 166 167 void nvram_write_byte(unsigned char c, int i) 168 { 169 unsigned long flags; 170 171 spin_lock_irqsave(&rtc_lock, flags); 172 __nvram_write_byte(c, i); 173 spin_unlock_irqrestore(&rtc_lock, flags); 174 } 175 EXPORT_SYMBOL(nvram_write_byte); 176 177 int __nvram_check_checksum(void) 178 { 179 return mach_check_checksum(); 180 } 181 EXPORT_SYMBOL(__nvram_check_checksum); 182 183 int nvram_check_checksum(void) 184 { 185 unsigned long flags; 186 int rv; 187 188 spin_lock_irqsave(&rtc_lock, flags); 189 rv = __nvram_check_checksum(); 190 spin_unlock_irqrestore(&rtc_lock, flags); 191 return rv; 192 } 193 EXPORT_SYMBOL(nvram_check_checksum); 194 195 static void __nvram_set_checksum(void) 196 { 197 mach_set_checksum(); 198 } 199 200 #if 0 201 void nvram_set_checksum(void) 202 { 203 unsigned long flags; 204 205 spin_lock_irqsave(&rtc_lock, flags); 206 __nvram_set_checksum(); 207 spin_unlock_irqrestore(&rtc_lock, flags); 208 } 209 #endif /* 0 */ 210 211 /* 212 * The are the file operation function for user access to /dev/nvram 213 */ 214 215 static loff_t nvram_llseek(struct file *file, loff_t offset, int origin) 216 { 217 lock_kernel(); 218 switch (origin) { 219 case 0: 220 /* nothing to do */ 221 break; 222 case 1: 223 offset += file->f_pos; 224 break; 225 case 2: 226 offset += NVRAM_BYTES; 227 break; 228 } 229 unlock_kernel(); 230 return (offset >= 0) ? (file->f_pos = offset) : -EINVAL; 231 } 232 233 static ssize_t nvram_read(struct file *file, char __user *buf, 234 size_t count, loff_t *ppos) 235 { 236 unsigned char contents[NVRAM_BYTES]; 237 unsigned i = *ppos; 238 unsigned char *tmp; 239 240 spin_lock_irq(&rtc_lock); 241 242 if (!__nvram_check_checksum()) 243 goto checksum_err; 244 245 for (tmp = contents; count-- > 0 && i < NVRAM_BYTES; ++i, ++tmp) 246 *tmp = __nvram_read_byte(i); 247 248 spin_unlock_irq(&rtc_lock); 249 250 if (copy_to_user(buf, contents, tmp - contents)) 251 return -EFAULT; 252 253 *ppos = i; 254 255 return tmp - contents; 256 257 checksum_err: 258 spin_unlock_irq(&rtc_lock); 259 return -EIO; 260 } 261 262 static ssize_t nvram_write(struct file *file, const char __user *buf, 263 size_t count, loff_t *ppos) 264 { 265 unsigned char contents[NVRAM_BYTES]; 266 unsigned i = *ppos; 267 unsigned char *tmp; 268 int len; 269 270 len = (NVRAM_BYTES - i) < count ? (NVRAM_BYTES - i) : count; 271 if (copy_from_user(contents, buf, len)) 272 return -EFAULT; 273 274 spin_lock_irq(&rtc_lock); 275 276 if (!__nvram_check_checksum()) 277 goto checksum_err; 278 279 for (tmp = contents; count-- > 0 && i < NVRAM_BYTES; ++i, ++tmp) 280 __nvram_write_byte(*tmp, i); 281 282 __nvram_set_checksum(); 283 284 spin_unlock_irq(&rtc_lock); 285 286 *ppos = i; 287 288 return tmp - contents; 289 290 checksum_err: 291 spin_unlock_irq(&rtc_lock); 292 return -EIO; 293 } 294 295 static int nvram_ioctl(struct inode *inode, struct file *file, 296 unsigned int cmd, unsigned long arg) 297 { 298 int i; 299 300 switch (cmd) { 301 302 case NVRAM_INIT: 303 /* initialize NVRAM contents and checksum */ 304 if (!capable(CAP_SYS_ADMIN)) 305 return -EACCES; 306 307 spin_lock_irq(&rtc_lock); 308 309 for (i = 0; i < NVRAM_BYTES; ++i) 310 __nvram_write_byte(0, i); 311 __nvram_set_checksum(); 312 313 spin_unlock_irq(&rtc_lock); 314 return 0; 315 316 case NVRAM_SETCKS: 317 /* just set checksum, contents unchanged (maybe useful after 318 * checksum garbaged somehow...) */ 319 if (!capable(CAP_SYS_ADMIN)) 320 return -EACCES; 321 322 spin_lock_irq(&rtc_lock); 323 __nvram_set_checksum(); 324 spin_unlock_irq(&rtc_lock); 325 return 0; 326 327 default: 328 return -ENOTTY; 329 } 330 } 331 332 static int nvram_open(struct inode *inode, struct file *file) 333 { 334 lock_kernel(); 335 spin_lock(&nvram_state_lock); 336 337 if ((nvram_open_cnt && (file->f_flags & O_EXCL)) || 338 (nvram_open_mode & NVRAM_EXCL) || 339 ((file->f_mode & FMODE_WRITE) && (nvram_open_mode & NVRAM_WRITE))) { 340 spin_unlock(&nvram_state_lock); 341 unlock_kernel(); 342 return -EBUSY; 343 } 344 345 if (file->f_flags & O_EXCL) 346 nvram_open_mode |= NVRAM_EXCL; 347 if (file->f_mode & FMODE_WRITE) 348 nvram_open_mode |= NVRAM_WRITE; 349 nvram_open_cnt++; 350 351 spin_unlock(&nvram_state_lock); 352 unlock_kernel(); 353 354 return 0; 355 } 356 357 static int nvram_release(struct inode *inode, struct file *file) 358 { 359 spin_lock(&nvram_state_lock); 360 361 nvram_open_cnt--; 362 363 /* if only one instance is open, clear the EXCL bit */ 364 if (nvram_open_mode & NVRAM_EXCL) 365 nvram_open_mode &= ~NVRAM_EXCL; 366 if (file->f_mode & FMODE_WRITE) 367 nvram_open_mode &= ~NVRAM_WRITE; 368 369 spin_unlock(&nvram_state_lock); 370 371 return 0; 372 } 373 374 #ifndef CONFIG_PROC_FS 375 static int nvram_add_proc_fs(void) 376 { 377 return 0; 378 } 379 380 #else 381 382 static int nvram_proc_read(struct seq_file *seq, void *offset) 383 { 384 unsigned char contents[NVRAM_BYTES]; 385 int i = 0; 386 387 spin_lock_irq(&rtc_lock); 388 for (i = 0; i < NVRAM_BYTES; ++i) 389 contents[i] = __nvram_read_byte(i); 390 spin_unlock_irq(&rtc_lock); 391 392 mach_proc_infos(contents, seq, offset); 393 394 return 0; 395 } 396 397 static int nvram_proc_open(struct inode *inode, struct file *file) 398 { 399 return single_open(file, nvram_proc_read, NULL); 400 } 401 402 static const struct file_operations nvram_proc_fops = { 403 .owner = THIS_MODULE, 404 .open = nvram_proc_open, 405 .read = seq_read, 406 .llseek = seq_lseek, 407 .release = single_release, 408 }; 409 410 static int nvram_add_proc_fs(void) 411 { 412 if (!proc_create("driver/nvram", 0, NULL, &nvram_proc_fops)) 413 return -ENOMEM; 414 return 0; 415 } 416 417 #endif /* CONFIG_PROC_FS */ 418 419 static const struct file_operations nvram_fops = { 420 .owner = THIS_MODULE, 421 .llseek = nvram_llseek, 422 .read = nvram_read, 423 .write = nvram_write, 424 .ioctl = nvram_ioctl, 425 .open = nvram_open, 426 .release = nvram_release, 427 }; 428 429 static struct miscdevice nvram_dev = { 430 NVRAM_MINOR, 431 "nvram", 432 &nvram_fops 433 }; 434 435 static int __init nvram_init(void) 436 { 437 int ret; 438 439 /* First test whether the driver should init at all */ 440 if (!CHECK_DRIVER_INIT()) 441 return -ENODEV; 442 443 ret = misc_register(&nvram_dev); 444 if (ret) { 445 printk(KERN_ERR "nvram: can't misc_register on minor=%d\n", 446 NVRAM_MINOR); 447 goto out; 448 } 449 ret = nvram_add_proc_fs(); 450 if (ret) { 451 printk(KERN_ERR "nvram: can't create /proc/driver/nvram\n"); 452 goto outmisc; 453 } 454 ret = 0; 455 printk(KERN_INFO "Non-volatile memory driver v" NVRAM_VERSION "\n"); 456 out: 457 return ret; 458 outmisc: 459 misc_deregister(&nvram_dev); 460 goto out; 461 } 462 463 static void __exit nvram_cleanup_module(void) 464 { 465 remove_proc_entry("driver/nvram", NULL); 466 misc_deregister(&nvram_dev); 467 } 468 469 module_init(nvram_init); 470 module_exit(nvram_cleanup_module); 471 472 /* 473 * Machine specific functions 474 */ 475 476 #if MACH == PC 477 478 static int pc_check_checksum(void) 479 { 480 int i; 481 unsigned short sum = 0; 482 unsigned short expect; 483 484 for (i = PC_CKS_RANGE_START; i <= PC_CKS_RANGE_END; ++i) 485 sum += __nvram_read_byte(i); 486 expect = __nvram_read_byte(PC_CKS_LOC)<<8 | 487 __nvram_read_byte(PC_CKS_LOC+1); 488 return (sum & 0xffff) == expect; 489 } 490 491 static void pc_set_checksum(void) 492 { 493 int i; 494 unsigned short sum = 0; 495 496 for (i = PC_CKS_RANGE_START; i <= PC_CKS_RANGE_END; ++i) 497 sum += __nvram_read_byte(i); 498 __nvram_write_byte(sum >> 8, PC_CKS_LOC); 499 __nvram_write_byte(sum & 0xff, PC_CKS_LOC + 1); 500 } 501 502 #ifdef CONFIG_PROC_FS 503 504 static char *floppy_types[] = { 505 "none", "5.25'' 360k", "5.25'' 1.2M", "3.5'' 720k", "3.5'' 1.44M", 506 "3.5'' 2.88M", "3.5'' 2.88M" 507 }; 508 509 static char *gfx_types[] = { 510 "EGA, VGA, ... (with BIOS)", 511 "CGA (40 cols)", 512 "CGA (80 cols)", 513 "monochrome", 514 }; 515 516 static void pc_proc_infos(unsigned char *nvram, struct seq_file *seq, 517 void *offset) 518 { 519 int checksum; 520 int type; 521 522 spin_lock_irq(&rtc_lock); 523 checksum = __nvram_check_checksum(); 524 spin_unlock_irq(&rtc_lock); 525 526 seq_printf(seq, "Checksum status: %svalid\n", checksum ? "" : "not "); 527 528 seq_printf(seq, "# floppies : %d\n", 529 (nvram[6] & 1) ? (nvram[6] >> 6) + 1 : 0); 530 seq_printf(seq, "Floppy 0 type : "); 531 type = nvram[2] >> 4; 532 if (type < ARRAY_SIZE(floppy_types)) 533 seq_printf(seq, "%s\n", floppy_types[type]); 534 else 535 seq_printf(seq, "%d (unknown)\n", type); 536 seq_printf(seq, "Floppy 1 type : "); 537 type = nvram[2] & 0x0f; 538 if (type < ARRAY_SIZE(floppy_types)) 539 seq_printf(seq, "%s\n", floppy_types[type]); 540 else 541 seq_printf(seq, "%d (unknown)\n", type); 542 543 seq_printf(seq, "HD 0 type : "); 544 type = nvram[4] >> 4; 545 if (type) 546 seq_printf(seq, "%02x\n", type == 0x0f ? nvram[11] : type); 547 else 548 seq_printf(seq, "none\n"); 549 550 seq_printf(seq, "HD 1 type : "); 551 type = nvram[4] & 0x0f; 552 if (type) 553 seq_printf(seq, "%02x\n", type == 0x0f ? nvram[12] : type); 554 else 555 seq_printf(seq, "none\n"); 556 557 seq_printf(seq, "HD type 48 data: %d/%d/%d C/H/S, precomp %d, lz %d\n", 558 nvram[18] | (nvram[19] << 8), 559 nvram[20], nvram[25], 560 nvram[21] | (nvram[22] << 8), nvram[23] | (nvram[24] << 8)); 561 seq_printf(seq, "HD type 49 data: %d/%d/%d C/H/S, precomp %d, lz %d\n", 562 nvram[39] | (nvram[40] << 8), 563 nvram[41], nvram[46], 564 nvram[42] | (nvram[43] << 8), nvram[44] | (nvram[45] << 8)); 565 566 seq_printf(seq, "DOS base memory: %d kB\n", nvram[7] | (nvram[8] << 8)); 567 seq_printf(seq, "Extended memory: %d kB (configured), %d kB (tested)\n", 568 nvram[9] | (nvram[10] << 8), nvram[34] | (nvram[35] << 8)); 569 570 seq_printf(seq, "Gfx adapter : %s\n", 571 gfx_types[(nvram[6] >> 4) & 3]); 572 573 seq_printf(seq, "FPU : %sinstalled\n", 574 (nvram[6] & 2) ? "" : "not "); 575 576 return; 577 } 578 #endif 579 580 #endif /* MACH == PC */ 581 582 #if MACH == ATARI 583 584 static int atari_check_checksum(void) 585 { 586 int i; 587 unsigned char sum = 0; 588 589 for (i = ATARI_CKS_RANGE_START; i <= ATARI_CKS_RANGE_END; ++i) 590 sum += __nvram_read_byte(i); 591 return (__nvram_read_byte(ATARI_CKS_LOC) == (~sum & 0xff)) && 592 (__nvram_read_byte(ATARI_CKS_LOC + 1) == (sum & 0xff)); 593 } 594 595 static void atari_set_checksum(void) 596 { 597 int i; 598 unsigned char sum = 0; 599 600 for (i = ATARI_CKS_RANGE_START; i <= ATARI_CKS_RANGE_END; ++i) 601 sum += __nvram_read_byte(i); 602 __nvram_write_byte(~sum, ATARI_CKS_LOC); 603 __nvram_write_byte(sum, ATARI_CKS_LOC + 1); 604 } 605 606 #ifdef CONFIG_PROC_FS 607 608 static struct { 609 unsigned char val; 610 char *name; 611 } boot_prefs[] = { 612 { 0x80, "TOS" }, 613 { 0x40, "ASV" }, 614 { 0x20, "NetBSD (?)" }, 615 { 0x10, "Linux" }, 616 { 0x00, "unspecified" } 617 }; 618 619 static char *languages[] = { 620 "English (US)", 621 "German", 622 "French", 623 "English (UK)", 624 "Spanish", 625 "Italian", 626 "6 (undefined)", 627 "Swiss (French)", 628 "Swiss (German)" 629 }; 630 631 static char *dateformat[] = { 632 "MM%cDD%cYY", 633 "DD%cMM%cYY", 634 "YY%cMM%cDD", 635 "YY%cDD%cMM", 636 "4 (undefined)", 637 "5 (undefined)", 638 "6 (undefined)", 639 "7 (undefined)" 640 }; 641 642 static char *colors[] = { 643 "2", "4", "16", "256", "65536", "??", "??", "??" 644 }; 645 646 static void atari_proc_infos(unsigned char *nvram, struct seq_file *seq, 647 void *offset) 648 { 649 int checksum = nvram_check_checksum(); 650 int i; 651 unsigned vmode; 652 653 seq_printf(seq, "Checksum status : %svalid\n", checksum ? "" : "not "); 654 655 seq_printf(seq, "Boot preference : "); 656 for (i = ARRAY_SIZE(boot_prefs) - 1; i >= 0; --i) { 657 if (nvram[1] == boot_prefs[i].val) { 658 seq_printf(seq, "%s\n", boot_prefs[i].name); 659 break; 660 } 661 } 662 if (i < 0) 663 seq_printf(seq, "0x%02x (undefined)\n", nvram[1]); 664 665 seq_printf(seq, "SCSI arbitration : %s\n", 666 (nvram[16] & 0x80) ? "on" : "off"); 667 seq_printf(seq, "SCSI host ID : "); 668 if (nvram[16] & 0x80) 669 seq_printf(seq, "%d\n", nvram[16] & 7); 670 else 671 seq_printf(seq, "n/a\n"); 672 673 /* the following entries are defined only for the Falcon */ 674 if ((atari_mch_cookie >> 16) != ATARI_MCH_FALCON) 675 return; 676 677 seq_printf(seq, "OS language : "); 678 if (nvram[6] < ARRAY_SIZE(languages)) 679 seq_printf(seq, "%s\n", languages[nvram[6]]); 680 else 681 seq_printf(seq, "%u (undefined)\n", nvram[6]); 682 seq_printf(seq, "Keyboard language: "); 683 if (nvram[7] < ARRAY_SIZE(languages)) 684 seq_printf(seq, "%s\n", languages[nvram[7]]); 685 else 686 seq_printf(seq, "%u (undefined)\n", nvram[7]); 687 seq_printf(seq, "Date format : "); 688 seq_printf(seq, dateformat[nvram[8] & 7], 689 nvram[9] ? nvram[9] : '/', nvram[9] ? nvram[9] : '/'); 690 seq_printf(seq, ", %dh clock\n", nvram[8] & 16 ? 24 : 12); 691 seq_printf(seq, "Boot delay : "); 692 if (nvram[10] == 0) 693 seq_printf(seq, "default"); 694 else 695 seq_printf(seq, "%ds%s\n", nvram[10], 696 nvram[10] < 8 ? ", no memory test" : ""); 697 698 vmode = (nvram[14] << 8) || nvram[15]; 699 seq_printf(seq, 700 "Video mode : %s colors, %d columns, %s %s monitor\n", 701 colors[vmode & 7], 702 vmode & 8 ? 80 : 40, 703 vmode & 16 ? "VGA" : "TV", vmode & 32 ? "PAL" : "NTSC"); 704 seq_printf(seq, " %soverscan, compat. mode %s%s\n", 705 vmode & 64 ? "" : "no ", 706 vmode & 128 ? "on" : "off", 707 vmode & 256 ? 708 (vmode & 16 ? ", line doubling" : ", half screen") : ""); 709 710 return; 711 } 712 #endif 713 714 #endif /* MACH == ATARI */ 715 716 MODULE_LICENSE("GPL"); 717 MODULE_ALIAS_MISCDEV(NVRAM_MINOR); 718