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 /* Brightness is 0 - 8, as described above.  Value 0 is for the BIOS to use */
  37 #define GET_BRIGHTNESS                  0x00
  38 #define SET_BRIGHTNESS                  0x01
  39
  40 /* first byte:
  41  * 0x00 - wireless is off
  42  * 0x01 - wireless is on
  43  * second byte:
  44  * 0x02 - 3G is off
  45  * 0x03 - 3G is on
  46  * TODO, verify 3G is correct, that doesn't seem right...
  47  */
  48 #define GET_WIRELESS_BUTTON             0x02
  49 #define SET_WIRELESS_BUTTON             0x03
  50
  51 /* 0 is off, 1 is on */
  52 #define GET_BACKLIGHT                   0x04
  53 #define SET_BACKLIGHT                   0x05
  54
  55 /*
  56  * 0x80 or 0x00 - no action
  57  * 0x81 - recovery key pressed
  58  */
  59 #define GET_RECOVERY_METHOD             0x06
  60 #define SET_RECOVERY_METHOD             0x07
  61
  62 /* 0 is low, 1 is high */
  63 #define GET_PERFORMANCE_LEVEL           0x08
  64 #define SET_PERFORMANCE_LEVEL           0x09
  65
  66 /*
  67  * Tell the BIOS that Linux is running on this machine.
  68  * 81 is on, 80 is off
  69  */
  70 #define SET_LINUX                       0x0a
  71
  72
  73 #define MAIN_FUNCTION                   0x4c49
  74
  75 #define SABI_HEADER_PORT                0x00
  76 #define SABI_HEADER_RE_MEM              0x02
  77 #define SABI_HEADER_IFACEFUNC           0x03
  78 #define SABI_HEADER_EN_MEM              0x04
  79 #define SABI_HEADER_DATA_OFFSET         0x05
  80 #define SABI_HEADER_DATA_SEGMENT        0x07
  81
  82 #define SABI_IFACE_MAIN                 0x00
  83 #define SABI_IFACE_SUB                  0x02
  84 #define SABI_IFACE_COMPLETE             0x04
  85 #define SABI_IFACE_DATA                 0x05
  86
  87 /* Structure to get data back to the calling function */
  88 struct sabi_retval {
  89         u8 retval[20];
  90 };
  91
  92 static void __iomem *sabi;
  93 static void __iomem *sabi_iface;
  94 static void __iomem *f0000_segment;
  95 static struct backlight_device *backlight_device;
  96 static struct mutex sabi_mutex;
  97 static struct platform_device *sdev;
  98 static struct rfkill *rfk;
  99
 100 static int force;
 101 module_param(force, bool, 0);
 102 MODULE_PARM_DESC(force,
 103                 "Disable the DMI check and forces the driver to be loaded");
 104
 105 static int debug;
 106 module_param(debug, bool, S_IRUGO | S_IWUSR);
 107 MODULE_PARM_DESC(debug, "Debug enabled or not");
 108
 109 static int sabi_get_command(u8 command, struct sabi_retval *sretval)
 110 {
 111         int retval = 0;
 112         u16 port = readw(sabi + SABI_HEADER_PORT);
 113
 114         mutex_lock(&sabi_mutex);
 115
 116         /* enable memory to be able to write to it */
 117         outb(readb(sabi + SABI_HEADER_EN_MEM), port);
 118
 119         /* write out the command */
 120         writew(MAIN_FUNCTION, sabi_iface + SABI_IFACE_MAIN);
 121         writew(command, sabi_iface + SABI_IFACE_SUB);
 122         writeb(0, sabi_iface + SABI_IFACE_COMPLETE);
 123         outb(readb(sabi + SABI_HEADER_IFACEFUNC), port);
 124
 125         /* write protect memory to make it safe */
 126         outb(readb(sabi + SABI_HEADER_RE_MEM), port);
 127
 128         /* see if the command actually succeeded */
 129         if (readb(sabi_iface + SABI_IFACE_COMPLETE) == 0xaa &&
 130             readb(sabi_iface + SABI_IFACE_DATA) != 0xff) {
 131                 /*
 132                  * It did!
 133                  * Save off the data into a structure so the caller use it.
 134                  * Right now we only care about the first 4 bytes,
 135                  * I suppose there are commands that need more, but I don't
 136                  * know about them.
 137                  */
 138                 sretval->retval[0] = readb(sabi_iface + SABI_IFACE_DATA);
 139                 sretval->retval[1] = readb(sabi_iface + SABI_IFACE_DATA + 1);
 140                 sretval->retval[2] = readb(sabi_iface + SABI_IFACE_DATA + 2);
 141                 sretval->retval[3] = readb(sabi_iface + SABI_IFACE_DATA + 3);
 142                 goto exit;
 143         }
 144
 145         /* Something bad happened, so report it and error out */
 146         printk(KERN_WARNING "SABI command 0x%02x failed with completion flag 0x%02x and output 0x%02x\n",
 147                 command, readb(sabi_iface + SABI_IFACE_COMPLETE),
 148                 readb(sabi_iface + SABI_IFACE_DATA));
 149         retval = -EINVAL;
 150 exit:
 151         mutex_unlock(&sabi_mutex);
 152         return retval;
 153
 154 }
 155
 156 static int sabi_set_command(u8 command, u8 data)
 157 {
 158         int retval = 0;
 159         u16 port = readw(sabi + SABI_HEADER_PORT);
 160
 161         mutex_lock(&sabi_mutex);
 162
 163         /* enable memory to be able to write to it */
 164         outb(readb(sabi + SABI_HEADER_EN_MEM), port);
 165
 166         /* write out the command */
 167         writew(MAIN_FUNCTION, sabi_iface + SABI_IFACE_MAIN);
 168         writew(command, sabi_iface + SABI_IFACE_SUB);
 169         writeb(0, sabi_iface + SABI_IFACE_COMPLETE);
 170         writeb(data, sabi_iface + SABI_IFACE_DATA);
 171         outb(readb(sabi + SABI_HEADER_IFACEFUNC), port);
 172
 173         /* write protect memory to make it safe */
 174         outb(readb(sabi + SABI_HEADER_RE_MEM), port);
 175
 176         /* see if the command actually succeeded */
 177         if (readb(sabi_iface + SABI_IFACE_COMPLETE) == 0xaa &&
 178             readb(sabi_iface + SABI_IFACE_DATA) != 0xff) {
 179                 /* it did! */
 180                 goto exit;
 181         }
 182
 183         /* Something bad happened, so report it and error out */
 184         printk(KERN_WARNING "SABI command 0x%02x failed with completion flag 0x%02x and output 0x%02x\n",
 185                 command, readb(sabi_iface + SABI_IFACE_COMPLETE),
 186                 readb(sabi_iface + SABI_IFACE_DATA));
 187         retval = -EINVAL;
 188 exit:
 189         mutex_unlock(&sabi_mutex);
 190         return retval;
 191 }
 192
 193 static void test_backlight(void)
 194 {
 195         struct sabi_retval sretval;
 196
 197         sabi_get_command(GET_BACKLIGHT, &sretval);
 198         printk(KERN_DEBUG "backlight = 0x%02x\n", sretval.retval[0]);
 199
 200         sabi_set_command(SET_BACKLIGHT, 0);
 201         printk(KERN_DEBUG "backlight should be off\n");
 202
 203         sabi_get_command(GET_BACKLIGHT, &sretval);
 204         printk(KERN_DEBUG "backlight = 0x%02x\n", sretval.retval[0]);
 205
 206         msleep(1000);
 207
 208         sabi_set_command(SET_BACKLIGHT, 1);
 209         printk(KERN_DEBUG "backlight should be on\n");
 210
 211         sabi_get_command(GET_BACKLIGHT, &sretval);
 212         printk(KERN_DEBUG "backlight = 0x%02x\n", sretval.retval[0]);
 213 }
 214
 215 static void test_wireless(void)
 216 {
 217         struct sabi_retval sretval;
 218
 219         sabi_get_command(GET_WIRELESS_BUTTON, &sretval);
 220         printk(KERN_DEBUG "wireless led = 0x%02x\n", sretval.retval[0]);
 221
 222         sabi_set_command(SET_WIRELESS_BUTTON, 0);
 223         printk(KERN_DEBUG "wireless led should be off\n");
 224
 225         sabi_get_command(GET_WIRELESS_BUTTON, &sretval);
 226         printk(KERN_DEBUG "wireless led = 0x%02x\n", sretval.retval[0]);
 227
 228         msleep(1000);
 229
 230         sabi_set_command(SET_WIRELESS_BUTTON, 1);
 231         printk(KERN_DEBUG "wireless led should be on\n");
 232
 233         sabi_get_command(GET_WIRELESS_BUTTON, &sretval);
 234         printk(KERN_DEBUG "wireless led = 0x%02x\n", sretval.retval[0]);
 235 }
 236
 237 static u8 read_brightness(void)
 238 {
 239         struct sabi_retval sretval;
 240         int user_brightness = 0;
 241         int retval;
 242
 243         retval = sabi_get_command(GET_BRIGHTNESS, &sretval);
 244         if (!retval)
 245                 user_brightness = sretval.retval[0];
 246                 if (user_brightness != 0)
 247                         --user_brightness;
 248         return user_brightness;
 249 }
 250
 251 static void set_brightness(u8 user_brightness)
 252 {
 253         sabi_set_command(SET_BRIGHTNESS, user_brightness + 1);
 254 }
 255
 256 static int get_brightness(struct backlight_device *bd)
 257 {
 258         return (int)read_brightness();
 259 }
 260
 261 static int update_status(struct backlight_device *bd)
 262 {
 263         set_brightness(bd->props.brightness);
 264
 265         if (bd->props.power == FB_BLANK_UNBLANK)
 266                 sabi_set_command(SET_BACKLIGHT, 1);
 267         else
 268                 sabi_set_command(SET_BACKLIGHT, 0);
 269         return 0;
 270 }
 271
 272 static struct backlight_ops backlight_ops = {
 273         .get_brightness = get_brightness,
 274         .update_status  = update_status,
 275 };
 276
 277 static int rfkill_set(void *data, bool blocked)
 278 {
 279         /* Do something with blocked...*/
 280         /*
 281          * blocked == false is on
 282          * blocked == true is off
 283          */
 284         if (blocked)
 285                 sabi_set_command(SET_WIRELESS_BUTTON, 0);
 286         else
 287                 sabi_set_command(SET_WIRELESS_BUTTON, 1);
 288
 289         return 0;
 290 }
 291
 292 static struct rfkill_ops rfkill_ops = {
 293         .set_block = rfkill_set,
 294 };
 295
 296 static int init_wireless(struct platform_device *sdev)
 297 {
 298         int retval;
 299
 300         rfk = rfkill_alloc("samsung-wifi", &sdev->dev, RFKILL_TYPE_WLAN,
 301                            &rfkill_ops, NULL);
 302         if (!rfk)
 303                 return -ENOMEM;
 304
 305         retval = rfkill_register(rfk);
 306         if (retval) {
 307                 rfkill_destroy(rfk);
 308                 return -ENODEV;
 309         }
 310
 311         return 0;
 312 }
 313
 314 static void destroy_wireless(void)
 315 {
 316         rfkill_unregister(rfk);
 317         rfkill_destroy(rfk);
 318 }
 319
 320 static ssize_t get_silent_state(struct device *dev,
 321                                 struct device_attribute *attr, char *buf)
 322 {
 323         struct sabi_retval sretval;
 324         int retval;
 325
 326         /* Read the state */
 327         retval = sabi_get_command(GET_PERFORMANCE_LEVEL, &sretval);
 328         if (retval)
 329                 return retval;
 330
 331         /* The logic is backwards, yeah, lots of fun... */
 332         if (sretval.retval[0] == 0)
 333                 retval = 1;
 334         else
 335                 retval = 0;
 336         return sprintf(buf, "%d\n", retval);
 337 }
 338
 339 static ssize_t set_silent_state(struct device *dev,
 340                                 struct device_attribute *attr, const char *buf,
 341                                 size_t count)
 342 {
 343         char value;
 344
 345         if (count >= 1) {
 346                 value = buf[0];
 347                 if ((value == '0') || (value == 'n') || (value == 'N')) {
 348                         /* Turn speed up */
 349                         sabi_set_command(SET_PERFORMANCE_LEVEL, 0x01);
 350                 } else if ((value == '1') || (value == 'y') || (value == 'Y')) {
 351                         /* Turn speed down */
 352                         sabi_set_command(SET_PERFORMANCE_LEVEL, 0x00);
 353                 } else {
 354                         return -EINVAL;
 355                 }
 356         }
 357         return count;
 358 }
 359 static DEVICE_ATTR(silent, S_IWUGO | S_IRUGO,
 360                    get_silent_state, set_silent_state);
 361
 362
 363 static int __init dmi_check_cb(const struct dmi_system_id *id)
 364 {
 365         printk(KERN_INFO KBUILD_MODNAME ": found laptop model '%s'\n",
 366                 id->ident);
 367         return 0;
 368 }
 369
 370 static struct dmi_system_id __initdata samsung_dmi_table[] = {
 371         {
 372                 .ident = "N128",
 373                 .matches = {
 374                         DMI_MATCH(DMI_SYS_VENDOR,
 375                                         "SAMSUNG ELECTRONICS CO., LTD."),
 376                         DMI_MATCH(DMI_PRODUCT_NAME, "N128"),
 377                         DMI_MATCH(DMI_BOARD_NAME, "N128"),
 378                 },
 379                 .callback = dmi_check_cb,
 380         },
 381         {
 382                 .ident = "N130",
 383                 .matches = {
 384                         DMI_MATCH(DMI_SYS_VENDOR,
 385                                         "SAMSUNG ELECTRONICS CO., LTD."),
 386                         DMI_MATCH(DMI_PRODUCT_NAME, "N130"),
 387                         DMI_MATCH(DMI_BOARD_NAME, "N130"),
 388                 },
 389                 .callback = dmi_check_cb,
 390         },
 391         { },
 392 };
 393 MODULE_DEVICE_TABLE(dmi, samsung_dmi_table);
 394
 395 static int __init samsung_init(void)
 396 {
 397         struct backlight_properties props;
 398         struct sabi_retval sretval;
 399         const char *testStr = "SECLINUX";
 400         void __iomem *memcheck;
 401         unsigned int ifaceP;
 402         int pStr;
 403         int loca;
 404         int retval;
 405
 406         mutex_init(&sabi_mutex);
 407
 408         if (!force && !dmi_check_system(samsung_dmi_table))
 409                 return -ENODEV;
 410
 411         f0000_segment = ioremap(0xf0000, 0xffff);
 412         if (!f0000_segment) {
 413                 printk(KERN_ERR "Can't map the segment at 0xf0000\n");
 414                 return -EINVAL;
 415         }
 416
 417         /* Try to find the signature "SECLINUX" in memory to find the header */
 418         pStr = 0;
 419         memcheck = f0000_segment;
 420         for (loca = 0; loca < 0xffff; loca++) {
 421                 char temp = readb(memcheck + loca);
 422
 423                 if (temp == testStr[pStr]) {
 424                         if (pStr == strlen(testStr)-1)
 425                                 break;
 426                         ++pStr;
 427                 } else {
 428                         pStr = 0;
 429                 }
 430         }
 431         if (loca == 0xffff) {
 432                 printk(KERN_ERR "This computer does not support SABI\n");
 433                 goto error_no_signature;
 434                 }
 435
 436         /* point to the SMI port Number */
 437         loca += 1;
 438         sabi = (memcheck + loca);
 439
 440         if (debug) {
 441                 printk(KERN_DEBUG "This computer supports SABI==%x\n",
 442                         loca + 0xf0000 - 6);
 443                 printk(KERN_DEBUG "SABI header:\n");
 444                 printk(KERN_DEBUG " SMI Port Number = 0x%04x\n",
 445                         readw(sabi + SABI_HEADER_PORT));
 446                 printk(KERN_DEBUG " SMI Interface Function = 0x%02x\n",
 447                         readb(sabi + SABI_HEADER_IFACEFUNC));
 448                 printk(KERN_DEBUG " SMI enable memory buffer = 0x%02x\n",
 449                         readb(sabi + SABI_HEADER_EN_MEM));
 450                 printk(KERN_DEBUG " SMI restore memory buffer = 0x%02x\n",
 451                         readb(sabi + SABI_HEADER_RE_MEM));
 452                 printk(KERN_DEBUG " SABI data offset = 0x%04x\n",
 453                         readw(sabi + SABI_HEADER_DATA_OFFSET));
 454                 printk(KERN_DEBUG " SABI data segment = 0x%04x\n",
 455                         readw(sabi + SABI_HEADER_DATA_SEGMENT));
 456         }
 457
 458         /* Get a pointer to the SABI Interface */
 459         ifaceP = (readw(sabi + SABI_HEADER_DATA_SEGMENT) & 0x0ffff) << 4;
 460         ifaceP += readw(sabi + SABI_HEADER_DATA_OFFSET) & 0x0ffff;
 461         sabi_iface = ioremap(ifaceP, 16);
 462         if (!sabi_iface) {
 463                 printk(KERN_ERR "Can't remap %x\n", ifaceP);
 464                 goto exit;
 465         }
 466         if (debug) {
 467                 printk(KERN_DEBUG "ifaceP = 0x%08x\n", ifaceP);
 468                 printk(KERN_DEBUG "sabi_iface = %p\n", sabi_iface);
 469
 470                 test_backlight();
 471                 test_wireless();
 472
 473                 retval = sabi_get_command(GET_BRIGHTNESS, &sretval);
 474                 printk(KERN_DEBUG "brightness = 0x%02x\n", sretval.retval[0]);
 475         }
 476
 477         /* Turn on "Linux" mode in the BIOS */
 478         retval = sabi_set_command(SET_LINUX, 0x81);
 479         if (retval) {
 480                 printk(KERN_ERR KBUILD_MODNAME ": Linux mode was not set!\n");
 481                 goto error_no_platform;
 482         }
 483
 484         /* knock up a platform device to hang stuff off of */
 485         sdev = platform_device_register_simple("samsung", -1, NULL, 0);
 486         if (IS_ERR(sdev))
 487                 goto error_no_platform;
 488
 489         /* create a backlight device to talk to this one */
 490         memset(&props, 0, sizeof(struct backlight_properties));
 491         props.max_brightness = MAX_BRIGHT;
 492         backlight_device = backlight_device_register("samsung", &sdev->dev,
 493                                                      NULL, &backlight_ops,
 494                                                      &props);
 495         if (IS_ERR(backlight_device))
 496                 goto error_no_backlight;
 497
 498         backlight_device->props.brightness = read_brightness();
 499         backlight_device->props.power = FB_BLANK_UNBLANK;
 500         backlight_update_status(backlight_device);
 501
 502         retval = init_wireless(sdev);
 503         if (retval)
 504                 goto error_no_rfk;
 505
 506         retval = device_create_file(&sdev->dev, &dev_attr_silent);
 507         if (retval)
 508                 goto error_file_create;
 509
 510 exit:
 511         return 0;
 512
 513 error_file_create:
 514         destroy_wireless();
 515
 516 error_no_rfk:
 517         backlight_device_unregister(backlight_device);
 518
 519 error_no_backlight:
 520         platform_device_unregister(sdev);
 521
 522 error_no_platform:
 523         iounmap(sabi_iface);
 524
 525 error_no_signature:
 526         iounmap(f0000_segment);
 527         return -EINVAL;
 528 }
 529
 530 static void __exit samsung_exit(void)
 531 {
 532         /* Turn off "Linux" mode in the BIOS */
 533         sabi_set_command(SET_LINUX, 0x80);
 534
 535         device_remove_file(&sdev->dev, &dev_attr_silent);
 536         backlight_device_unregister(backlight_device);
 537         destroy_wireless();
 538         iounmap(sabi_iface);
 539         iounmap(f0000_segment);
 540         platform_device_unregister(sdev);
 541 }
 542
 543 module_init(samsung_init);
 544 module_exit(samsung_exit);
 545
 546 MODULE_AUTHOR("Greg Kroah-Hartman <gregkh@suse.de>");
 547 MODULE_DESCRIPTION("Samsung Backlight driver");
 548 MODULE_LICENSE("GPL");