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

   1 /*
   2  * Samsung Laptop driver
   3  *
   4  * Copyright (C) 2009,2011 Greg Kroah-Hartman (gregkh@suse.de)
   5  * Copyright (C) 2009,2011 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 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  13
  14 #include <linux/kernel.h>
  15 #include <linux/init.h>
  16 #include <linux/module.h>
  17 #include <linux/delay.h>
  18 #include <linux/pci.h>
  19 #include <linux/backlight.h>
  20 #include <linux/fb.h>
  21 #include <linux/dmi.h>
  22 #include <linux/platform_device.h>
  23 #include <linux/rfkill.h>
  24
  25 /*
  26  * This driver is needed because a number of Samsung laptops do not hook
  27  * their control settings through ACPI.  So we have to poke around in the
  28  * BIOS to do things like brightness values, and "special" key controls.
  29  */
  30
  31 /*
  32  * We have 0 - 8 as valid brightness levels.  The specs say that level 0 should
  33  * be reserved by the BIOS (which really doesn't make much sense), we tell
  34  * userspace that the value is 0 - 7 and then just tell the hardware 1 - 8
  35  */
  36 #define MAX_BRIGHT      0x07
  37
  38
  39 #define SABI_IFACE_MAIN                 0x00
  40 #define SABI_IFACE_SUB                  0x02
  41 #define SABI_IFACE_COMPLETE             0x04
  42 #define SABI_IFACE_DATA                 0x05
  43
  44 /* Structure to get data back to the calling function */
  45 struct sabi_retval {
  46         u8 retval[20];
  47 };
  48
  49 struct sabi_header_offsets {
  50         u8 port;
  51         u8 re_mem;
  52         u8 iface_func;
  53         u8 en_mem;
  54         u8 data_offset;
  55         u8 data_segment;
  56 };
  57
  58 struct sabi_commands {
  59         /*
  60          * Brightness is 0 - 8, as described above.
  61          * Value 0 is for the BIOS to use
  62          */
  63         u8 get_brightness;
  64         u8 set_brightness;
  65
  66         /*
  67          * first byte:
  68          * 0x00 - wireless is off
  69          * 0x01 - wireless is on
  70          * second byte:
  71          * 0x02 - 3G is off
  72          * 0x03 - 3G is on
  73          * TODO, verify 3G is correct, that doesn't seem right...
  74          */
  75         u8 get_wireless_button;
  76         u8 set_wireless_button;
  77
  78         /* 0 is off, 1 is on */
  79         u8 get_backlight;
  80         u8 set_backlight;
  81
  82         /*
  83          * 0x80 or 0x00 - no action
  84          * 0x81 - recovery key pressed
  85          */
  86         u8 get_recovery_mode;
  87         u8 set_recovery_mode;
  88
  89         /*
  90          * on seclinux: 0 is low, 1 is high,
  91          * on swsmi: 0 is normal, 1 is silent, 2 is turbo
  92          */
  93         u8 get_performance_level;
  94         u8 set_performance_level;
  95
  96         /*
  97          * Tell the BIOS that Linux is running on this machine.
  98          * 81 is on, 80 is off
  99          */
 100         u8 set_linux;
 101 };
 102
 103 struct sabi_performance_level {
 104         const char *name;
 105         u8 value;
 106 };
 107
 108 struct sabi_config {
 109         const char *test_string;
 110         u16 main_function;
 111         struct sabi_header_offsets header_offsets;
 112         struct sabi_commands commands;
 113         struct sabi_performance_level performance_levels[4];
 114 };
 115
 116 static struct sabi_config sabi_configs[] = {
 117         {
 118                 .test_string = "SECLINUX",
 119
 120                 .main_function = 0x4c49,
 121
 122                 .header_offsets = {
 123                         .port = 0x00,
 124                         .re_mem = 0x02,
 125                         .iface_func = 0x03,
 126                         .en_mem = 0x04,
 127                         .data_offset = 0x05,
 128                         .data_segment = 0x07,
 129                 },
 130
 131                 .commands = {
 132                         .get_brightness = 0x00,
 133                         .set_brightness = 0x01,
 134
 135                         .get_wireless_button = 0x02,
 136                         .set_wireless_button = 0x03,
 137
 138                         .get_backlight = 0x04,
 139                         .set_backlight = 0x05,
 140
 141                         .get_recovery_mode = 0x06,
 142                         .set_recovery_mode = 0x07,
 143
 144                         .get_performance_level = 0x08,
 145                         .set_performance_level = 0x09,
 146
 147                         .set_linux = 0x0a,
 148                 },
 149
 150                 .performance_levels = {
 151                         {
 152                                 .name = "silent",
 153                                 .value = 0,
 154                         },
 155                         {
 156                                 .name = "normal",
 157                                 .value = 1,
 158                         },
 159                         { },
 160                 },
 161         },
 162         {
 163                 .test_string = "SwSmi@",
 164
 165                 .main_function = 0x5843,
 166
 167                 .header_offsets = {
 168                         .port = 0x00,
 169                         .re_mem = 0x04,
 170                         .iface_func = 0x02,
 171                         .en_mem = 0x03,
 172                         .data_offset = 0x05,
 173                         .data_segment = 0x07,
 174                 },
 175
 176                 .commands = {
 177                         .get_brightness = 0x10,
 178                         .set_brightness = 0x11,
 179
 180                         .get_wireless_button = 0x12,
 181                         .set_wireless_button = 0x13,
 182
 183                         .get_backlight = 0x2d,
 184                         .set_backlight = 0x2e,
 185
 186                         .get_recovery_mode = 0xff,
 187                         .set_recovery_mode = 0xff,
 188
 189                         .get_performance_level = 0x31,
 190                         .set_performance_level = 0x32,
 191
 192                         .set_linux = 0xff,
 193                 },
 194
 195                 .performance_levels = {
 196                         {
 197                                 .name = "normal",
 198                                 .value = 0,
 199                         },
 200                         {
 201                                 .name = "silent",
 202                                 .value = 1,
 203                         },
 204                         {
 205                                 .name = "overclock",
 206                                 .value = 2,
 207                         },
 208                         { },
 209                 },
 210         },
 211         { },
 212 };
 213
 214 static struct sabi_config *sabi_config;
 215
 216 static void __iomem *sabi;
 217 static void __iomem *sabi_iface;
 218 static void __iomem *f0000_segment;
 219 static struct backlight_device *backlight_device;
 220 static struct mutex sabi_mutex;
 221 static struct platform_device *sdev;
 222 static struct rfkill *rfk;
 223
 224 static int force;
 225 module_param(force, bool, 0);
 226 MODULE_PARM_DESC(force,
 227                 "Disable the DMI check and forces the driver to be loaded");
 228
 229 static int debug;
 230 module_param(debug, bool, S_IRUGO | S_IWUSR);
 231 MODULE_PARM_DESC(debug, "Debug enabled or not");
 232
 233 static int sabi_get_command(u8 command, struct sabi_retval *sretval)
 234 {
 235         int retval = 0;
 236         u16 port = readw(sabi + sabi_config->header_offsets.port);
 237         u8 complete, iface_data;
 238
 239         mutex_lock(&sabi_mutex);
 240
 241         /* enable memory to be able to write to it */
 242         outb(readb(sabi + sabi_config->header_offsets.en_mem), port);
 243
 244         /* write out the command */
 245         writew(sabi_config->main_function, sabi_iface + SABI_IFACE_MAIN);
 246         writew(command, sabi_iface + SABI_IFACE_SUB);
 247         writeb(0, sabi_iface + SABI_IFACE_COMPLETE);
 248         outb(readb(sabi + sabi_config->header_offsets.iface_func), port);
 249
 250         /* write protect memory to make it safe */
 251         outb(readb(sabi + sabi_config->header_offsets.re_mem), port);
 252
 253         /* see if the command actually succeeded */
 254         complete = readb(sabi_iface + SABI_IFACE_COMPLETE);
 255         iface_data = readb(sabi_iface + SABI_IFACE_DATA);
 256         if (complete != 0xaa || iface_data == 0xff) {
 257                 pr_warn("SABI get command 0x%02x failed with completion flag 0x%02x and data 0x%02x\n",
 258                         command, complete, iface_data);
 259                 retval = -EINVAL;
 260                 goto exit;
 261         }
 262         /*
 263          * Save off the data into a structure so the caller use it.
 264          * Right now we only want the first 4 bytes,
 265          * There are commands that need more, but not for the ones we
 266          * currently care about.
 267          */
 268         sretval->retval[0] = readb(sabi_iface + SABI_IFACE_DATA);
 269         sretval->retval[1] = readb(sabi_iface + SABI_IFACE_DATA + 1);
 270         sretval->retval[2] = readb(sabi_iface + SABI_IFACE_DATA + 2);
 271         sretval->retval[3] = readb(sabi_iface + SABI_IFACE_DATA + 3);
 272
 273 exit:
 274         mutex_unlock(&sabi_mutex);
 275         return retval;
 276
 277 }
 278
 279 static int sabi_set_command(u8 command, u8 data)
 280 {
 281         int retval = 0;
 282         u16 port = readw(sabi + sabi_config->header_offsets.port);
 283         u8 complete, iface_data;
 284
 285         mutex_lock(&sabi_mutex);
 286
 287         /* enable memory to be able to write to it */
 288         outb(readb(sabi + sabi_config->header_offsets.en_mem), port);
 289
 290         /* write out the command */
 291         writew(sabi_config->main_function, sabi_iface + SABI_IFACE_MAIN);
 292         writew(command, sabi_iface + SABI_IFACE_SUB);
 293         writeb(0, sabi_iface + SABI_IFACE_COMPLETE);
 294         writeb(data, sabi_iface + SABI_IFACE_DATA);
 295         outb(readb(sabi + sabi_config->header_offsets.iface_func), port);
 296
 297         /* write protect memory to make it safe */
 298         outb(readb(sabi + sabi_config->header_offsets.re_mem), port);
 299
 300         /* see if the command actually succeeded */
 301         complete = readb(sabi_iface + SABI_IFACE_COMPLETE);
 302         iface_data = readb(sabi_iface + SABI_IFACE_DATA);
 303         if (complete != 0xaa || iface_data == 0xff) {
 304                 pr_warn("SABI set command 0x%02x failed with completion flag 0x%02x and data 0x%02x\n",
 305                        command, complete, iface_data);
 306                 retval = -EINVAL;
 307         }
 308
 309         mutex_unlock(&sabi_mutex);
 310         return retval;
 311 }
 312
 313 static void test_backlight(void)
 314 {
 315         struct sabi_retval sretval;
 316
 317         sabi_get_command(sabi_config->commands.get_backlight, &sretval);
 318         printk(KERN_DEBUG "backlight = 0x%02x\n", sretval.retval[0]);
 319
 320         sabi_set_command(sabi_config->commands.set_backlight, 0);
 321         printk(KERN_DEBUG "backlight should be off\n");
 322
 323         sabi_get_command(sabi_config->commands.get_backlight, &sretval);
 324         printk(KERN_DEBUG "backlight = 0x%02x\n", sretval.retval[0]);
 325
 326         msleep(1000);
 327
 328         sabi_set_command(sabi_config->commands.set_backlight, 1);
 329         printk(KERN_DEBUG "backlight should be on\n");
 330
 331         sabi_get_command(sabi_config->commands.get_backlight, &sretval);
 332         printk(KERN_DEBUG "backlight = 0x%02x\n", sretval.retval[0]);
 333 }
 334
 335 static void test_wireless(void)
 336 {
 337         struct sabi_retval sretval;
 338
 339         sabi_get_command(sabi_config->commands.get_wireless_button, &sretval);
 340         printk(KERN_DEBUG "wireless led = 0x%02x\n", sretval.retval[0]);
 341
 342         sabi_set_command(sabi_config->commands.set_wireless_button, 0);
 343         printk(KERN_DEBUG "wireless led should be off\n");
 344
 345         sabi_get_command(sabi_config->commands.get_wireless_button, &sretval);
 346         printk(KERN_DEBUG "wireless led = 0x%02x\n", sretval.retval[0]);
 347
 348         msleep(1000);
 349
 350         sabi_set_command(sabi_config->commands.set_wireless_button, 1);
 351         printk(KERN_DEBUG "wireless led should be on\n");
 352
 353         sabi_get_command(sabi_config->commands.get_wireless_button, &sretval);
 354         printk(KERN_DEBUG "wireless led = 0x%02x\n", sretval.retval[0]);
 355 }
 356
 357 static u8 read_brightness(void)
 358 {
 359         struct sabi_retval sretval;
 360         int user_brightness = 0;
 361         int retval;
 362
 363         retval = sabi_get_command(sabi_config->commands.get_brightness,
 364                                   &sretval);
 365         if (!retval)
 366                 user_brightness = sretval.retval[0];
 367                 if (user_brightness != 0)
 368                         --user_brightness;
 369         return user_brightness;
 370 }
 371
 372 static void set_brightness(u8 user_brightness)
 373 {
 374         sabi_set_command(sabi_config->commands.set_brightness,
 375                          user_brightness + 1);
 376 }
 377
 378 static int get_brightness(struct backlight_device *bd)
 379 {
 380         return (int)read_brightness();
 381 }
 382
 383 static int update_status(struct backlight_device *bd)
 384 {
 385         set_brightness(bd->props.brightness);
 386
 387         if (bd->props.power == FB_BLANK_UNBLANK)
 388                 sabi_set_command(sabi_config->commands.set_backlight, 1);
 389         else
 390                 sabi_set_command(sabi_config->commands.set_backlight, 0);
 391         return 0;
 392 }
 393
 394 static const struct backlight_ops backlight_ops = {
 395         .get_brightness = get_brightness,
 396         .update_status  = update_status,
 397 };
 398
 399 static int rfkill_set(void *data, bool blocked)
 400 {
 401         /* Do something with blocked...*/
 402         /*
 403          * blocked == false is on
 404          * blocked == true is off
 405          */
 406         if (blocked)
 407                 sabi_set_command(sabi_config->commands.set_wireless_button, 0);
 408         else
 409                 sabi_set_command(sabi_config->commands.set_wireless_button, 1);
 410
 411         return 0;
 412 }
 413
 414 static struct rfkill_ops rfkill_ops = {
 415         .set_block = rfkill_set,
 416 };
 417
 418 static int init_wireless(struct platform_device *sdev)
 419 {
 420         int retval;
 421
 422         rfk = rfkill_alloc("samsung-wifi", &sdev->dev, RFKILL_TYPE_WLAN,
 423                            &rfkill_ops, NULL);
 424         if (!rfk)
 425                 return -ENOMEM;
 426
 427         retval = rfkill_register(rfk);
 428         if (retval) {
 429                 rfkill_destroy(rfk);
 430                 return -ENODEV;
 431         }
 432
 433         return 0;
 434 }
 435
 436 static void destroy_wireless(void)
 437 {
 438         rfkill_unregister(rfk);
 439         rfkill_destroy(rfk);
 440 }
 441
 442 static ssize_t get_performance_level(struct device *dev,
 443                                      struct device_attribute *attr, char *buf)
 444 {
 445         struct sabi_retval sretval;
 446         int retval;
 447         int i;
 448
 449         /* Read the state */
 450         retval = sabi_get_command(sabi_config->commands.get_performance_level,
 451                                   &sretval);
 452         if (retval)
 453                 return retval;
 454
 455         /* The logic is backwards, yeah, lots of fun... */
 456         for (i = 0; sabi_config->performance_levels[i].name; ++i) {
 457                 if (sretval.retval[0] == sabi_config->performance_levels[i].value)
 458                         return sprintf(buf, "%s\n", sabi_config->performance_levels[i].name);
 459         }
 460         return sprintf(buf, "%s\n", "unknown");
 461 }
 462
 463 static ssize_t set_performance_level(struct device *dev,
 464                                 struct device_attribute *attr, const char *buf,
 465                                 size_t count)
 466 {
 467         if (count >= 1) {
 468                 int i;
 469                 for (i = 0; sabi_config->performance_levels[i].name; ++i) {
 470                         struct sabi_performance_level *level =
 471                                 &sabi_config->performance_levels[i];
 472                         if (!strncasecmp(level->name, buf, strlen(level->name))) {
 473                                 sabi_set_command(sabi_config->commands.set_performance_level,
 474                                                  level->value);
 475                                 break;
 476                         }
 477                 }
 478                 if (!sabi_config->performance_levels[i].name)
 479                         return -EINVAL;
 480         }
 481         return count;
 482 }
 483 static DEVICE_ATTR(performance_level, S_IWUSR | S_IRUGO,
 484                    get_performance_level, set_performance_level);
 485
 486
 487 static int __init dmi_check_cb(const struct dmi_system_id *id)
 488 {
 489         pr_info("found laptop model '%s'\n",
 490                 id->ident);
 491         return 0;
 492 }
 493
 494 static struct dmi_system_id __initdata samsung_dmi_table[] = {
 495         {
 496                 .ident = "N128",
 497                 .matches = {
 498                         DMI_MATCH(DMI_SYS_VENDOR,
 499                                         "SAMSUNG ELECTRONICS CO., LTD."),
 500                         DMI_MATCH(DMI_PRODUCT_NAME, "N128"),
 501                         DMI_MATCH(DMI_BOARD_NAME, "N128"),
 502                 },
 503                 .callback = dmi_check_cb,
 504         },
 505         {
 506                 .ident = "N130",
 507                 .matches = {
 508                         DMI_MATCH(DMI_SYS_VENDOR,
 509                                         "SAMSUNG ELECTRONICS CO., LTD."),
 510                         DMI_MATCH(DMI_PRODUCT_NAME, "N130"),
 511                         DMI_MATCH(DMI_BOARD_NAME, "N130"),
 512                 },
 513                 .callback = dmi_check_cb,
 514         },
 515         {
 516                 .ident = "X125",
 517                 .matches = {
 518                         DMI_MATCH(DMI_SYS_VENDOR,
 519                                         "SAMSUNG ELECTRONICS CO., LTD."),
 520                         DMI_MATCH(DMI_PRODUCT_NAME, "X125"),
 521                         DMI_MATCH(DMI_BOARD_NAME, "X125"),
 522                 },
 523                 .callback = dmi_check_cb,
 524         },
 525         {
 526                 .ident = "X120/X170",
 527                 .matches = {
 528                         DMI_MATCH(DMI_SYS_VENDOR,
 529                                         "SAMSUNG ELECTRONICS CO., LTD."),
 530                         DMI_MATCH(DMI_PRODUCT_NAME, "X120/X170"),
 531                         DMI_MATCH(DMI_BOARD_NAME, "X120/X170"),
 532                 },
 533                 .callback = dmi_check_cb,
 534         },
 535         {
 536                 .ident = "NC10",
 537                 .matches = {
 538                         DMI_MATCH(DMI_SYS_VENDOR,
 539                                         "SAMSUNG ELECTRONICS CO., LTD."),
 540                         DMI_MATCH(DMI_PRODUCT_NAME, "NC10"),
 541                         DMI_MATCH(DMI_BOARD_NAME, "NC10"),
 542                 },
 543                 .callback = dmi_check_cb,
 544         },
 545                 {
 546                 .ident = "NP-Q45",
 547                 .matches = {
 548                         DMI_MATCH(DMI_SYS_VENDOR,
 549                                         "SAMSUNG ELECTRONICS CO., LTD."),
 550                         DMI_MATCH(DMI_PRODUCT_NAME, "SQ45S70S"),
 551                         DMI_MATCH(DMI_BOARD_NAME, "SQ45S70S"),
 552                 },
 553                 .callback = dmi_check_cb,
 554                 },
 555         {
 556                 .ident = "X360",
 557                 .matches = {
 558                         DMI_MATCH(DMI_SYS_VENDOR,
 559                                         "SAMSUNG ELECTRONICS CO., LTD."),
 560                         DMI_MATCH(DMI_PRODUCT_NAME, "X360"),
 561                         DMI_MATCH(DMI_BOARD_NAME, "X360"),
 562                 },
 563                 .callback = dmi_check_cb,
 564         },
 565         {
 566                 .ident = "R518",
 567                 .matches = {
 568                         DMI_MATCH(DMI_SYS_VENDOR,
 569                                         "SAMSUNG ELECTRONICS CO., LTD."),
 570                         DMI_MATCH(DMI_PRODUCT_NAME, "R518"),
 571                         DMI_MATCH(DMI_BOARD_NAME, "R518"),
 572                 },
 573                 .callback = dmi_check_cb,
 574         },
 575         {
 576                 .ident = "R519/R719",
 577                 .matches = {
 578                         DMI_MATCH(DMI_SYS_VENDOR,
 579                                         "SAMSUNG ELECTRONICS CO., LTD."),
 580                         DMI_MATCH(DMI_PRODUCT_NAME, "R519/R719"),
 581                         DMI_MATCH(DMI_BOARD_NAME, "R519/R719"),
 582                 },
 583                 .callback = dmi_check_cb,
 584         },
 585         {
 586                 .ident = "N150/N210/N220",
 587                 .matches = {
 588                         DMI_MATCH(DMI_SYS_VENDOR,
 589                                         "SAMSUNG ELECTRONICS CO., LTD."),
 590                         DMI_MATCH(DMI_PRODUCT_NAME, "N150/N210/N220"),
 591                         DMI_MATCH(DMI_BOARD_NAME, "N150/N210/N220"),
 592                 },
 593                 .callback = dmi_check_cb,
 594         },
 595         {
 596                 .ident = "R530/R730",
 597                 .matches = {
 598                       DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."),
 599                       DMI_MATCH(DMI_PRODUCT_NAME, "R530/R730"),
 600                       DMI_MATCH(DMI_BOARD_NAME, "R530/R730"),
 601                 },
 602                 .callback = dmi_check_cb,
 603         },
 604         {
 605                 .ident = "NF110/NF210/NF310",
 606                 .matches = {
 607                         DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."),
 608                         DMI_MATCH(DMI_PRODUCT_NAME, "NF110/NF210/NF310"),
 609                         DMI_MATCH(DMI_BOARD_NAME, "NF110/NF210/NF310"),
 610                 },
 611                 .callback = dmi_check_cb,
 612         },
 613         {
 614                 .ident = "N145P/N250P/N260P",
 615                 .matches = {
 616                         DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."),
 617                         DMI_MATCH(DMI_PRODUCT_NAME, "N145P/N250P/N260P"),
 618                         DMI_MATCH(DMI_BOARD_NAME, "N145P/N250P/N260P"),
 619                 },
 620                 .callback = dmi_check_cb,
 621         },
 622         {
 623                 .ident = "R70/R71",
 624                 .matches = {
 625                         DMI_MATCH(DMI_SYS_VENDOR,
 626                                         "SAMSUNG ELECTRONICS CO., LTD."),
 627                         DMI_MATCH(DMI_PRODUCT_NAME, "R70/R71"),
 628                         DMI_MATCH(DMI_BOARD_NAME, "R70/R71"),
 629                 },
 630                 .callback = dmi_check_cb,
 631         },
 632         { },
 633 };
 634 MODULE_DEVICE_TABLE(dmi, samsung_dmi_table);
 635
 636 static int find_signature(void __iomem *memcheck, const char *testStr)
 637 {
 638         int i = 0;
 639         int loca;
 640
 641         for (loca = 0; loca < 0xffff; loca++) {
 642                 char temp = readb(memcheck + loca);
 643
 644                 if (temp == testStr[i]) {
 645                         if (i == strlen(testStr)-1)
 646                                 break;
 647                         ++i;
 648                 } else {
 649                         i = 0;
 650                 }
 651         }
 652         return loca;
 653 }
 654
 655 static int __init samsung_init(void)
 656 {
 657         struct backlight_properties props;
 658         struct sabi_retval sretval;
 659         unsigned int ifaceP;
 660         int i;
 661         int loca;
 662         int retval;
 663
 664         mutex_init(&sabi_mutex);
 665
 666         if (!force && !dmi_check_system(samsung_dmi_table))
 667                 return -ENODEV;
 668
 669         f0000_segment = ioremap(0xf0000, 0xffff);
 670         if (!f0000_segment) {
 671                 pr_err("Can't map the segment at 0xf0000\n");
 672                 return -EINVAL;
 673         }
 674
 675         /* Try to find one of the signatures in memory to find the header */
 676         for (i = 0; sabi_configs[i].test_string != 0; ++i) {
 677                 sabi_config = &sabi_configs[i];
 678                 loca = find_signature(f0000_segment, sabi_config->test_string);
 679                 if (loca != 0xffff)
 680                         break;
 681         }
 682
 683         if (loca == 0xffff) {
 684                 pr_err("This computer does not support SABI\n");
 685                 goto error_no_signature;
 686         }
 687
 688         /* point to the SMI port Number */
 689         loca += 1;
 690         sabi = (f0000_segment + loca);
 691
 692         if (debug) {
 693                 printk(KERN_DEBUG "This computer supports SABI==%x\n",
 694                         loca + 0xf0000 - 6);
 695                 printk(KERN_DEBUG "SABI header:\n");
 696                 printk(KERN_DEBUG " SMI Port Number = 0x%04x\n",
 697                         readw(sabi + sabi_config->header_offsets.port));
 698                 printk(KERN_DEBUG " SMI Interface Function = 0x%02x\n",
 699                         readb(sabi + sabi_config->header_offsets.iface_func));
 700                 printk(KERN_DEBUG " SMI enable memory buffer = 0x%02x\n",
 701                         readb(sabi + sabi_config->header_offsets.en_mem));
 702                 printk(KERN_DEBUG " SMI restore memory buffer = 0x%02x\n",
 703                         readb(sabi + sabi_config->header_offsets.re_mem));
 704                 printk(KERN_DEBUG " SABI data offset = 0x%04x\n",
 705                         readw(sabi + sabi_config->header_offsets.data_offset));
 706                 printk(KERN_DEBUG " SABI data segment = 0x%04x\n",
 707                         readw(sabi + sabi_config->header_offsets.data_segment));
 708         }
 709
 710         /* Get a pointer to the SABI Interface */
 711         ifaceP = (readw(sabi + sabi_config->header_offsets.data_segment) & 0x0ffff) << 4;
 712         ifaceP += readw(sabi + sabi_config->header_offsets.data_offset) & 0x0ffff;
 713         sabi_iface = ioremap(ifaceP, 16);
 714         if (!sabi_iface) {
 715                 pr_err("Can't remap %x\n", ifaceP);
 716                 goto exit;
 717         }
 718         if (debug) {
 719                 printk(KERN_DEBUG "ifaceP = 0x%08x\n", ifaceP);
 720                 printk(KERN_DEBUG "sabi_iface = %p\n", sabi_iface);
 721
 722                 test_backlight();
 723                 test_wireless();
 724
 725                 retval = sabi_get_command(sabi_config->commands.get_brightness,
 726                                           &sretval);
 727                 printk(KERN_DEBUG "brightness = 0x%02x\n", sretval.retval[0]);
 728         }
 729
 730         /* Turn on "Linux" mode in the BIOS */
 731         if (sabi_config->commands.set_linux != 0xff) {
 732                 retval = sabi_set_command(sabi_config->commands.set_linux,
 733                                           0x81);
 734                 if (retval) {
 735                         pr_warn("Linux mode was not set!\n");
 736                         goto error_no_platform;
 737                 }
 738         }
 739
 740         /* knock up a platform device to hang stuff off of */
 741         sdev = platform_device_register_simple("samsung", -1, NULL, 0);
 742         if (IS_ERR(sdev))
 743                 goto error_no_platform;
 744
 745         /* create a backlight device to talk to this one */
 746         memset(&props, 0, sizeof(struct backlight_properties));
 747         props.max_brightness = MAX_BRIGHT;
 748         backlight_device = backlight_device_register("samsung", &sdev->dev,
 749                                                      NULL, &backlight_ops,
 750                                                      &props);
 751         if (IS_ERR(backlight_device))
 752                 goto error_no_backlight;
 753
 754         backlight_device->props.brightness = read_brightness();
 755         backlight_device->props.power = FB_BLANK_UNBLANK;
 756         backlight_update_status(backlight_device);
 757
 758         retval = init_wireless(sdev);
 759         if (retval)
 760                 goto error_no_rfk;
 761
 762         retval = device_create_file(&sdev->dev, &dev_attr_performance_level);
 763         if (retval)
 764                 goto error_file_create;
 765
 766 exit:
 767         return 0;
 768
 769 error_file_create:
 770         destroy_wireless();
 771
 772 error_no_rfk:
 773         backlight_device_unregister(backlight_device);
 774
 775 error_no_backlight:
 776         platform_device_unregister(sdev);
 777
 778 error_no_platform:
 779         iounmap(sabi_iface);
 780
 781 error_no_signature:
 782         iounmap(f0000_segment);
 783         return -EINVAL;
 784 }
 785
 786 static void __exit samsung_exit(void)
 787 {
 788         /* Turn off "Linux" mode in the BIOS */
 789         if (sabi_config->commands.set_linux != 0xff)
 790                 sabi_set_command(sabi_config->commands.set_linux, 0x80);
 791
 792         device_remove_file(&sdev->dev, &dev_attr_performance_level);
 793         backlight_device_unregister(backlight_device);
 794         destroy_wireless();
 795         iounmap(sabi_iface);
 796         iounmap(f0000_segment);
 797         platform_device_unregister(sdev);
 798 }
 799
 800 module_init(samsung_init);
 801 module_exit(samsung_exit);
 802
 803 MODULE_AUTHOR("Greg Kroah-Hartman <gregkh@suse.de>");
 804 MODULE_DESCRIPTION("Samsung Backlight driver");
 805 MODULE_LICENSE("GPL");