drivers/staging/samsung-laptop/samsung-laptop.c

   1 /*
   2  * Samsung N130 Laptop driver
   3  *
   4  * Copyright (C) 2009 Greg Kroah-Hartman (gregkh@suse.de)
   5  * Copyright (C) 2009 Novell Inc.
   6  *
   7  * This program is free software; you can redistribute it and/or modify it
   8  * under the terms of the GNU General Public License version 2 as published by
   9  * the Free Software Foundation.
  10  *
  11  */
  12 #include <linux/kernel.h>
  13 #include <linux/init.h>
  14 #include <linux/module.h>
  15 #include <linux/delay.h>
  16 #include <linux/pci.h>
  17 #include <linux/backlight.h>
  18 #include <linux/fb.h>
  19 #include <linux/dmi.h>
  20 #include <linux/platform_device.h>
  21 #include <linux/rfkill.h>
  22
  23 /*
  24  * This driver is needed because a number of Samsung laptops do not hook
  25  * their control settings through ACPI.  So we have to poke around in the
  26  * BIOS to do things like brightness values, and "special" key controls.
  27  */
  28
  29 /*
  30  * We have 0 - 8 as valid brightness levels.  The specs say that level 0 should
  31  * be reserved by the BIOS (which really doesn't make much sense), we tell
  32  * userspace that the value is 0 - 7 and then just tell the hardware 1 - 8
  33  */
  34 #define MAX_BRIGHT      0x07
  35
  36
  37 #define SABI_IFACE_MAIN                 0x00
  38 #define SABI_IFACE_SUB                  0x02
  39 #define SABI_IFACE_COMPLETE             0x04
  40 #define SABI_IFACE_DATA                 0x05
  41
  42 /* Structure to get data back to the calling function */
  43 struct sabi_retval {
  44         u8 retval[20];
  45 };
  46
  47 struct sabi_header_offsets {
  48         u8 port;
  49         u8 re_mem;
  50         u8 iface_func;
  51         u8 en_mem;
  52         u8 data_offset;
  53         u8 data_segment;
  54 };
  55
  56 struct sabi_commands {
  57         /*
  58          * Brightness is 0 - 8, as described above.
  59          * Value 0 is for the BIOS to use
  60          */
  61         u8 get_brightness;
  62         u8 set_brightness;
  63
  64         /*
  65          * first byte:
  66          * 0x00 - wireless is off
  67          * 0x01 - wireless is on
  68          * second byte:
  69          * 0x02 - 3G is off
  70          * 0x03 - 3G is on
  71          * TODO, verify 3G is correct, that doesn't seem right...
  72          */
  73         u8 get_wireless_button;
  74         u8 set_wireless_button;
  75
  76         /* 0 is off, 1 is on */
  77         u8 get_backlight;
  78         u8 set_backlight;
  79
  80         /*
  81          * 0x80 or 0x00 - no action
  82          * 0x81 - recovery key pressed
  83          */
  84         u8 get_recovery_mode;
  85         u8 set_recovery_mode;
  86
  87         /*
  88          * on seclinux: 0 is low, 1 is high,
  89          * on swsmi: 0 is normal, 1 is silent, 2 is turbo
  90          */
  91         u8 get_performance_level;
  92         u8 set_performance_level;
  93
  94         /*
  95          * Tell the BIOS that Linux is running on this machine.
  96          * 81 is on, 80 is off
  97          */
  98         u8 set_linux;
  99 };
 100
 101 struct sabi_performance_level {
 102         const char *name;
 103         u8 value;
 104 };
 105
 106 struct sabi_config {
 107         const char *test_string;
 108         u16 main_function;
 109         struct sabi_header_offsets header_offsets;
 110         struct sabi_commands commands;
 111         struct sabi_performance_level performance_levels[4];
 112 };
 113
 114 static struct sabi_config sabi_configs[] = {
 115         {
 116                 .test_string = "SECLINUX",
 117
 118                 .main_function = 0x4c59,
 119
 120                 .header_offsets = {
 121                         .port = 0x00,
 122                         .re_mem = 0x02,
 123                         .iface_func = 0x03,
 124                         .en_mem = 0x04,
 125                         .data_offset = 0x05,
 126                         .data_segment = 0x07,
 127                 },
 128
 129                 .commands = {
 130                         .get_brightness = 0x00,
 131                         .set_brightness = 0x01,
 132
 133                         .get_wireless_button = 0x02,
 134                         .set_wireless_button = 0x03,
 135
 136                         .get_backlight = 0x04,
 137                         .set_backlight = 0x05,
 138
 139                         .get_recovery_mode = 0x06,
 140                         .set_recovery_mode = 0x07,
 141
 142                         .get_performance_level = 0x08,
 143                         .set_performance_level = 0x09,
 144
 145                         .set_linux = 0x0a,
 146                 },
 147
 148                 .performance_levels = {
 149                         {
 150                                 .name = "silent",
 151                                 .value = 0,
 152                         },
 153                         {
 154                                 .name = "normal",
 155                                 .value = 1,
 156                         },
 157                         { },
 158                 },
 159         },
 160         {
 161                 .test_string = "SwSmi@",
 162
 163                 .main_function = 0x5843,
 164
 165                 .header_offsets = {
 166                         .port = 0x00,
 167                         .re_mem = 0x04,
 168                         .iface_func = 0x02,
 169                         .en_mem = 0x03,
 170                         .data_offset = 0x05,
 171                         .data_segment = 0x07,
 172                 },
 173
 174                 .commands = {
 175                         .get_brightness = 0x10,
 176                         .set_brightness = 0x11,
 177
 178                         .get_wireless_button = 0x12,
 179                         .set_wireless_button = 0x13,
 180
 181                         .get_backlight = 0x2d,
 182                         .set_backlight = 0x2e,
 183
 184                         .get_recovery_mode = 0xff,
 185                         .set_recovery_mode = 0xff,
 186
 187                         .get_performance_level = 0x31,
 188                         .set_performance_level = 0x32,
 189
 190                         .set_linux = 0xff,
 191                 },
 192
 193                 .performance_levels = {
 194                         {
 195                                 .name = "normal",
 196                                 .value = 0,
 197                         },
 198                         {
 199                                 .name = "silent",
 200                                 .value = 1,
 201                         },
 202                         {
 203                                 .name = "overclock",
 204                                 .value = 2,
 205                         },
 206                         { },
 207                 },
 208         },
 209         { },
 210 };
 211
 212 static struct sabi_config *sabi_config;
 213
 214 static void __iomem *sabi;
 215 static void __iomem *sabi_iface;
 216 static void __iomem *f0000_segment;
 217 static struct backlight_device *backlight_device;
 218 static struct mutex sabi_mutex;
 219 static struct platform_device *sdev;
 220 static struct rfkill *rfk;
 221
 222 static int force;
 223 module_param(force, bool, 0);
 224 MODULE_PARM_DESC(force,
 225                 "Disable the DMI check and forces the driver to be loaded");
 226
 227 static int debug;
 228 module_param(debug, bool, S_IRUGO | S_IWUSR);
 229 MODULE_PARM_DESC(debug, "Debug enabled or not");
 230
 231 static int sabi_get_command(u8 command, struct sabi_retval *sretval)
 232 {
 233         int retval = 0;
 234         u16 port = readw(sabi + sabi_config->header_offsets.port);
 235
 236         mutex_lock(&sabi_mutex);
 237
 238         /* enable memory to be able to write to it */
 239         outb(readb(sabi + sabi_config->header_offsets.en_mem), port);
 240
 241         /* write out the command */
 242         writew(sabi_config->main_function, sabi_iface + SABI_IFACE_MAIN);
 243         writew(command, sabi_iface + SABI_IFACE_SUB);
 244         writeb(0, sabi_iface + SABI_IFACE_COMPLETE);
 245         outb(readb(sabi + sabi_config->header_offsets.iface_func), port);
 246
 247         /* write protect memory to make it safe */
 248         outb(readb(sabi + sabi_config->header_offsets.re_mem), port);
 249
 250         /* see if the command actually succeeded */
 251         if (readb(sabi_iface + SABI_IFACE_COMPLETE) == 0xaa &&
 252             readb(sabi_iface + SABI_IFACE_DATA) != 0xff) {
 253                 /*
 254                  * It did!
 255                  * Save off the data into a structure so the caller use it.
 256                  * Right now we only care about the first 4 bytes,
 257                  * I suppose there are commands that need more, but I don't
 258                  * know about them.
 259                  */
 260                 sretval->retval[0] = readb(sabi_iface + SABI_IFACE_DATA);
 261                 sretval->retval[1] = readb(sabi_iface + SABI_IFACE_DATA + 1);
 262                 sretval->retval[2] = readb(sabi_iface + SABI_IFACE_DATA + 2);
 263                 sretval->retval[3] = readb(sabi_iface + SABI_IFACE_DATA + 3);
 264                 goto exit;
 265         }
 266
 267         /* Something bad happened, so report it and error out */
 268         printk(KERN_WARNING "SABI command 0x%02x failed with completion flag 0x%02x and output 0x%02x\n",
 269                 command, readb(sabi_iface + SABI_IFACE_COMPLETE),
 270                 readb(sabi_iface + SABI_IFACE_DATA));
 271         retval = -EINVAL;
 272 exit:
 273         mutex_unlock(&sabi_mutex);
 274         return retval;
 275
 276 }
 277
 278 static int sabi_set_command(u8 command, u8 data)
 279 {
 280         int retval = 0;
 281         u16 port = readw(sabi + sabi_config->header_offsets.port);
 282
 283         mutex_lock(&sabi_mutex);
 284
 285         /* enable memory to be able to write to it */
 286         outb(readb(sabi + sabi_config->header_offsets.en_mem), port);
 287
 288         /* write out the command */
 289         writew(sabi_config->main_function, sabi_iface + SABI_IFACE_MAIN);
 290         writew(command, sabi_iface + SABI_IFACE_SUB);
 291         writeb(0, sabi_iface + SABI_IFACE_COMPLETE);
 292         writeb(data, sabi_iface + SABI_IFACE_DATA);
 293         outb(readb(sabi + sabi_config->header_offsets.iface_func), port);
 294
 295         /* write protect memory to make it safe */
 296         outb(readb(sabi + sabi_config->header_offsets.re_mem), port);
 297
 298         /* see if the command actually succeeded */
 299         if (readb(sabi_iface + SABI_IFACE_COMPLETE) == 0xaa &&
 300             readb(sabi_iface + SABI_IFACE_DATA) != 0xff) {
 301                 /* it did! */
 302                 goto exit;
 303         }
 304
 305         /* Something bad happened, so report it and error out */
 306         printk(KERN_WARNING "SABI command 0x%02x failed with completion flag 0x%02x and output 0x%02x\n",
 307                 command, readb(sabi_iface + SABI_IFACE_COMPLETE),
 308                 readb(sabi_iface + SABI_IFACE_DATA));
 309         retval = -EINVAL;
 310 exit:
 311         mutex_unlock(&sabi_mutex);
 312         return retval;
 313 }
 314
 315 static void test_backlight(void)
 316 {
 317         struct sabi_retval sretval;
 318
 319         sabi_get_command(sabi_config->commands.get_backlight, &sretval);
 320         printk(KERN_DEBUG "backlight = 0x%02x\n", sretval.retval[0]);
 321
 322         sabi_set_command(sabi_config->commands.set_backlight, 0);
 323         printk(KERN_DEBUG "backlight should be off\n");
 324
 325         sabi_get_command(sabi_config->commands.get_backlight, &sretval);
 326         printk(KERN_DEBUG "backlight = 0x%02x\n", sretval.retval[0]);
 327
 328         msleep(1000);
 329
 330         sabi_set_command(sabi_config->commands.set_backlight, 1);
 331         printk(KERN_DEBUG "backlight should be on\n");
 332
 333         sabi_get_command(sabi_config->commands.get_backlight, &sretval);
 334         printk(KERN_DEBUG "backlight = 0x%02x\n", sretval.retval[0]);
 335 }
 336
 337 static void test_wireless(void)
 338 {
 339         struct sabi_retval sretval;
 340
 341         sabi_get_command(sabi_config->commands.get_wireless_button, &sretval);
 342         printk(KERN_DEBUG "wireless led = 0x%02x\n", sretval.retval[0]);
 343
 344         sabi_set_command(sabi_config->commands.set_wireless_button, 0);
 345         printk(KERN_DEBUG "wireless led should be off\n");
 346
 347         sabi_get_command(sabi_config->commands.get_wireless_button, &sretval);
 348         printk(KERN_DEBUG "wireless led = 0x%02x\n", sretval.retval[0]);
 349
 350         msleep(1000);
 351
 352         sabi_set_command(sabi_config->commands.set_wireless_button, 1);
 353         printk(KERN_DEBUG "wireless led should be on\n");
 354
 355         sabi_get_command(sabi_config->commands.get_wireless_button, &sretval);
 356         printk(KERN_DEBUG "wireless led = 0x%02x\n", sretval.retval[0]);
 357 }
 358
 359 static u8 read_brightness(void)
 360 {
 361         struct sabi_retval sretval;
 362         int user_brightness = 0;
 363         int retval;
 364
 365         retval = sabi_get_command(sabi_config->commands.get_brightness,
 366                                   &sretval);
 367         if (!retval)
 368                 user_brightness = sretval.retval[0];
 369                 if (user_brightness != 0)
 370                         --user_brightness;
 371         return user_brightness;
 372 }
 373
 374 static void set_brightness(u8 user_brightness)
 375 {
 376         sabi_set_command(sabi_config->commands.set_brightness,
 377                          user_brightness + 1);
 378 }
 379
 380 static int get_brightness(struct backlight_device *bd)
 381 {
 382         return (int)read_brightness();
 383 }
 384
 385 static int update_status(struct backlight_device *bd)
 386 {
 387         set_brightness(bd->props.brightness);
 388
 389         if (bd->props.power == FB_BLANK_UNBLANK)
 390                 sabi_set_command(sabi_config->commands.set_backlight, 1);
 391         else
 392                 sabi_set_command(sabi_config->commands.set_backlight, 0);
 393         return 0;
 394 }
 395
 396 static const struct backlight_ops backlight_ops = {
 397         .get_brightness = get_brightness,
 398         .update_status  = update_status,
 399 };
 400
 401 static int rfkill_set(void *data, bool blocked)
 402 {
 403         /* Do something with blocked...*/
 404         /*
 405          * blocked == false is on
 406          * blocked == true is off
 407          */
 408         if (blocked)
 409                 sabi_set_command(sabi_config->commands.set_wireless_button, 0);
 410         else
 411                 sabi_set_command(sabi_config->commands.set_wireless_button, 1);
 412
 413         return 0;
 414 }
 415
 416 static struct rfkill_ops rfkill_ops = {
 417         .set_block = rfkill_set,
 418 };
 419
 420 static int init_wireless(struct platform_device *sdev)
 421 {
 422         int retval;
 423
 424         rfk = rfkill_alloc("samsung-wifi", &sdev->dev, RFKILL_TYPE_WLAN,
 425                            &rfkill_ops, NULL);
 426         if (!rfk)
 427                 return -ENOMEM;
 428
 429         retval = rfkill_register(rfk);
 430         if (retval) {
 431                 rfkill_destroy(rfk);
 432                 return -ENODEV;
 433         }
 434
 435         return 0;
 436 }
 437
 438 static void destroy_wireless(void)
 439 {
 440         rfkill_unregister(rfk);
 441         rfkill_destroy(rfk);
 442 }
 443
 444 static ssize_t get_performance_level(struct device *dev,
 445                                      struct device_attribute *attr, char *buf)
 446 {
 447         struct sabi_retval sretval;
 448         int retval;
 449         int i;
 450
 451         /* Read the state */
 452         retval = sabi_get_command(sabi_config->commands.get_performance_level,
 453                                   &sretval);
 454         if (retval)
 455                 return retval;
 456
 457         /* The logic is backwards, yeah, lots of fun... */
 458         for (i = 0; sabi_config->performance_levels[i].name; ++i) {
 459                 if (sretval.retval[0] == sabi_config->performance_levels[i].value)
 460                         return sprintf(buf, "%s\n", sabi_config->performance_levels[i].name);
 461         }
 462         return sprintf(buf, "%s\n", "unknown");
 463 }
 464
 465 static ssize_t set_performance_level(struct device *dev,
 466                                 struct device_attribute *attr, const char *buf,
 467                                 size_t count)
 468 {
 469         if (count >= 1) {
 470                 int i;
 471                 for (i = 0; sabi_config->performance_levels[i].name; ++i) {
 472                         struct sabi_performance_level *level =
 473                                 &sabi_config->performance_levels[i];
 474                         if (!strncasecmp(level->name, buf, strlen(level->name))) {
 475                                 sabi_set_command(sabi_config->commands.set_performance_level,
 476                                                  level->value);
 477                                 break;
 478                         }
 479                 }
 480                 if (!sabi_config->performance_levels[i].name)
 481                         return -EINVAL;
 482         }
 483         return count;
 484 }
 485 static DEVICE_ATTR(performance_level, S_IWUSR | S_IRUGO,
 486                    get_performance_level, set_performance_level);
 487
 488
 489 static int __init dmi_check_cb(const struct dmi_system_id *id)
 490 {
 491         printk(KERN_INFO KBUILD_MODNAME ": found laptop model '%s'\n",
 492                 id->ident);
 493         return 0;
 494 }
 495
 496 static struct dmi_system_id __initdata samsung_dmi_table[] = {
 497         {
 498                 .ident = "N128",
 499                 .matches = {
 500                         DMI_MATCH(DMI_SYS_VENDOR,
 501                                         "SAMSUNG ELECTRONICS CO., LTD."),
 502                         DMI_MATCH(DMI_PRODUCT_NAME, "N128"),
 503                         DMI_MATCH(DMI_BOARD_NAME, "N128"),
 504                 },
 505                 .callback = dmi_check_cb,
 506         },
 507         {
 508                 .ident = "N130",
 509                 .matches = {
 510                         DMI_MATCH(DMI_SYS_VENDOR,
 511                                         "SAMSUNG ELECTRONICS CO., LTD."),
 512                         DMI_MATCH(DMI_PRODUCT_NAME, "N130"),
 513                         DMI_MATCH(DMI_BOARD_NAME, "N130"),
 514                 },
 515                 .callback = dmi_check_cb,
 516         },
 517         {
 518                 .ident = "X125",
 519                 .matches = {
 520                         DMI_MATCH(DMI_SYS_VENDOR,
 521                                         "SAMSUNG ELECTRONICS CO., LTD."),
 522                         DMI_MATCH(DMI_PRODUCT_NAME, "X125"),
 523                         DMI_MATCH(DMI_BOARD_NAME, "X125"),
 524                 },
 525                 .callback = dmi_check_cb,
 526         },
 527         { },
 528 };
 529 MODULE_DEVICE_TABLE(dmi, samsung_dmi_table);
 530
 531 static int find_signature(void __iomem *memcheck, const char *testStr)
 532 {
 533         int i = 0;
 534         int loca;
 535
 536         for (loca = 0; loca < 0xffff; loca++) {
 537                 char temp = readb(memcheck + loca);
 538
 539                 if (temp == testStr[i]) {
 540                         if (i == strlen(testStr)-1)
 541                                 break;
 542                         ++i;
 543                 } else {
 544                         i = 0;
 545                 }
 546         }
 547         return loca;
 548 }
 549
 550 static int __init samsung_init(void)
 551 {
 552         struct backlight_properties props;
 553         struct sabi_retval sretval;
 554         unsigned int ifaceP;
 555         int i;
 556         int loca;
 557         int retval;
 558
 559         mutex_init(&sabi_mutex);
 560
 561         if (!force && !dmi_check_system(samsung_dmi_table))
 562                 return -ENODEV;
 563
 564         f0000_segment = ioremap(0xf0000, 0xffff);
 565         if (!f0000_segment) {
 566                 printk(KERN_ERR "Can't map the segment at 0xf0000\n");
 567                 return -EINVAL;
 568         }
 569
 570         /* Try to find one of the signatures in memory to find the header */
 571         for (i = 0; sabi_configs[i].test_string != 0; ++i) {
 572                 sabi_config = &sabi_configs[i];
 573                 loca = find_signature(f0000_segment, sabi_config->test_string);
 574                 if (loca != 0xffff)
 575                         break;
 576         }
 577
 578         if (loca == 0xffff) {
 579                 printk(KERN_ERR "This computer does not support SABI\n");
 580                 goto error_no_signature;
 581         }
 582
 583         /* point to the SMI port Number */
 584         loca += 1;
 585         sabi = (f0000_segment + loca);
 586
 587         if (debug) {
 588                 printk(KERN_DEBUG "This computer supports SABI==%x\n",
 589                         loca + 0xf0000 - 6);
 590                 printk(KERN_DEBUG "SABI header:\n");
 591                 printk(KERN_DEBUG " SMI Port Number = 0x%04x\n",
 592                         readw(sabi + sabi_config->header_offsets.port));
 593                 printk(KERN_DEBUG " SMI Interface Function = 0x%02x\n",
 594                         readb(sabi + sabi_config->header_offsets.iface_func));
 595                 printk(KERN_DEBUG " SMI enable memory buffer = 0x%02x\n",
 596                         readb(sabi + sabi_config->header_offsets.en_mem));
 597                 printk(KERN_DEBUG " SMI restore memory buffer = 0x%02x\n",
 598                         readb(sabi + sabi_config->header_offsets.re_mem));
 599                 printk(KERN_DEBUG " SABI data offset = 0x%04x\n",
 600                         readw(sabi + sabi_config->header_offsets.data_offset));
 601                 printk(KERN_DEBUG " SABI data segment = 0x%04x\n",
 602                         readw(sabi + sabi_config->header_offsets.data_segment));
 603         }
 604
 605         /* Get a pointer to the SABI Interface */
 606         ifaceP = (readw(sabi + sabi_config->header_offsets.data_segment) & 0x0ffff) << 4;
 607         ifaceP += readw(sabi + sabi_config->header_offsets.data_offset) & 0x0ffff;
 608         sabi_iface = ioremap(ifaceP, 16);
 609         if (!sabi_iface) {
 610                 printk(KERN_ERR "Can't remap %x\n", ifaceP);
 611                 goto exit;
 612         }
 613         if (debug) {
 614                 printk(KERN_DEBUG "ifaceP = 0x%08x\n", ifaceP);
 615                 printk(KERN_DEBUG "sabi_iface = %p\n", sabi_iface);
 616
 617                 test_backlight();
 618                 test_wireless();
 619
 620                 retval = sabi_get_command(sabi_config->commands.get_brightness,
 621                                           &sretval);
 622                 printk(KERN_DEBUG "brightness = 0x%02x\n", sretval.retval[0]);
 623         }
 624
 625         /* Turn on "Linux" mode in the BIOS */
 626         if (sabi_config->commands.set_linux != 0xff) {
 627                 retval = sabi_set_command(sabi_config->commands.set_linux,
 628                                           0x81);
 629                 if (retval) {
 630                         printk(KERN_ERR KBUILD_MODNAME ": Linux mode was not set!\n");
 631                         goto error_no_platform;
 632                 }
 633         }
 634
 635         /* knock up a platform device to hang stuff off of */
 636         sdev = platform_device_register_simple("samsung", -1, NULL, 0);
 637         if (IS_ERR(sdev))
 638                 goto error_no_platform;
 639
 640         /* create a backlight device to talk to this one */
 641         memset(&props, 0, sizeof(struct backlight_properties));
 642         props.max_brightness = MAX_BRIGHT;
 643         backlight_device = backlight_device_register("samsung", &sdev->dev,
 644                                                      NULL, &backlight_ops,
 645                                                      &props);
 646         if (IS_ERR(backlight_device))
 647                 goto error_no_backlight;
 648
 649         backlight_device->props.brightness = read_brightness();
 650         backlight_device->props.power = FB_BLANK_UNBLANK;
 651         backlight_update_status(backlight_device);
 652
 653         retval = init_wireless(sdev);
 654         if (retval)
 655                 goto error_no_rfk;
 656
 657         retval = device_create_file(&sdev->dev, &dev_attr_performance_level);
 658         if (retval)
 659                 goto error_file_create;
 660
 661 exit:
 662         return 0;
 663
 664 error_file_create:
 665         destroy_wireless();
 666
 667 error_no_rfk:
 668         backlight_device_unregister(backlight_device);
 669
 670 error_no_backlight:
 671         platform_device_unregister(sdev);
 672
 673 error_no_platform:
 674         iounmap(sabi_iface);
 675
 676 error_no_signature:
 677         iounmap(f0000_segment);
 678         return -EINVAL;
 679 }
 680
 681 static void __exit samsung_exit(void)
 682 {
 683         /* Turn off "Linux" mode in the BIOS */
 684         if (sabi_config->commands.set_linux != 0xff)
 685                 sabi_set_command(sabi_config->commands.set_linux, 0x80);
 686
 687         device_remove_file(&sdev->dev, &dev_attr_performance_level);
 688         backlight_device_unregister(backlight_device);
 689         destroy_wireless();
 690         iounmap(sabi_iface);
 691         iounmap(f0000_segment);
 692         platform_device_unregister(sdev);
 693 }
 694
 695 module_init(samsung_init);
 696 module_exit(samsung_exit);
 697
 698 MODULE_AUTHOR("Greg Kroah-Hartman <gregkh@suse.de>");
 699 MODULE_DESCRIPTION("Samsung Backlight driver");
 700 MODULE_LICENSE("GPL");