LXR linux/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 */
  88struct sabi_retval {
  89        u8 retval[20];
  90};
  91
  92static void __iomem *sabi;
  93static void __iomem *sabi_iface;
  94static void __iomem *f0000_segment;
  95static struct backlight_device *backlight_device;
  96static struct mutex sabi_mutex;
  97static struct platform_device *sdev;
  98static struct rfkill *rfk;
  99
 100static int force;
 101module_param(force, bool, 0);
 102MODULE_PARM_DESC(force,
 103                "Disable the DMI check and forces the driver to be loaded");
 104
 105static int debug;
 106module_param(debug, bool, S_IRUGO | S_IWUSR);
 107MODULE_PARM_DESC(debug, "Debug enabled or not");
 108
 109static 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;
 150exit:
 151        mutex_unlock(&sabi_mutex);
 152        return retval;
 153
 154}
 155
 156static 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;
 188exit:
 189        mutex_unlock(&sabi_mutex);
 190        return retval;
 191}
 192
 193static 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
 215static 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
 237static 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
 251static void set_brightness(u8 user_brightness)
 252{
 253        sabi_set_command(SET_BRIGHTNESS, user_brightness + 1);
 254}
 255
 256static int get_brightness(struct backlight_device *bd)
 257{
 258        return (int)read_brightness();
 259}
 260
 261static 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
 272static const struct backlight_ops backlight_ops = {
 273        .get_brightness = get_brightness,
 274        .update_status  = update_status,
 275};
 276
 277static 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
 292static struct rfkill_ops rfkill_ops = {
 293        .set_block = rfkill_set,
 294};
 295
 296static 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
 314static void destroy_wireless(void)
 315{
 316        rfkill_unregister(rfk);
 317        rfkill_destroy(rfk);
 318}
 319
 320static 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
 339static 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}
 359static DEVICE_ATTR(silent, S_IWUSR | S_IRUGO,
 360                   get_silent_state, set_silent_state);
 361
 362
 363static 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
 370static 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};
 393MODULE_DEVICE_TABLE(dmi, samsung_dmi_table);
 394
 395static 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
 510exit:
 511        return 0;
 512
 513error_file_create:
 514        destroy_wireless();
 515
 516error_no_rfk:
 517        backlight_device_unregister(backlight_device);
 518
 519error_no_backlight:
 520        platform_device_unregister(sdev);
 521
 522error_no_platform:
 523        iounmap(sabi_iface);
 524
 525error_no_signature:
 526        iounmap(f0000_segment);
 527        return -EINVAL;
 528}
 529
 530static 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
 543module_init(samsung_init);
 544module_exit(samsung_exit);
 545
 546MODULE_AUTHOR("Greg Kroah-Hartman <gregkh@suse.de>");
 547MODULE_DESCRIPTION("Samsung Backlight driver");
 548MODULE_LICENSE("GPL");
 549