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