drivers/platform/x86/dell-wmi.c

   1 /*
   2  * Dell WMI hotkeys
   3  *
   4  * Copyright (C) 2008 Red Hat <mjg@redhat.com>
   5  * Copyright (C) 2014-2015 Pali Rohár <pali.rohar@gmail.com>
   6  *
   7  * Portions based on wistron_btns.c:
   8  * Copyright (C) 2005 Miloslav Trmac <mitr@volny.cz>
   9  * Copyright (C) 2005 Bernhard Rosenkraenzer <bero@arklinux.org>
  10  * Copyright (C) 2005 Dmitry Torokhov <dtor@mail.ru>
  11  *
  12  *  This program is free software; you can redistribute it and/or modify
  13  *  it under the terms of the GNU General Public License as published by
  14  *  the Free Software Foundation; either version 2 of the License, or
  15  *  (at your option) any later version.
  16  *
  17  *  This program is distributed in the hope that it will be useful,
  18  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  19  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  20  *  GNU General Public License for more details.
  21  *
  22  *  You should have received a copy of the GNU General Public License
  23  *  along with this program; if not, write to the Free Software
  24  *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  25  */
  26
  27 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  28
  29 #include <linux/kernel.h>
  30 #include <linux/module.h>
  31 #include <linux/init.h>
  32 #include <linux/slab.h>
  33 #include <linux/types.h>
  34 #include <linux/input.h>
  35 #include <linux/input/sparse-keymap.h>
  36 #include <linux/acpi.h>
  37 #include <linux/string.h>
  38 #include <linux/dmi.h>
  39 #include <linux/wmi.h>
  40 #include <acpi/video.h>
  41 #include "dell-smbios.h"
  42 #include "dell-wmi-descriptor.h"
  43
  44 MODULE_AUTHOR("Matthew Garrett <mjg@redhat.com>");
  45 MODULE_AUTHOR("Pali Rohár <pali.rohar@gmail.com>");
  46 MODULE_DESCRIPTION("Dell laptop WMI hotkeys driver");
  47 MODULE_LICENSE("GPL");
  48
  49 #define DELL_EVENT_GUID "9DBB5994-A997-11DA-B012-B622A1EF5492"
  50
  51 static bool wmi_requires_smbios_request;
  52
  53 MODULE_ALIAS("wmi:"DELL_EVENT_GUID);
  54
  55 struct dell_wmi_priv {
  56         struct input_dev *input_dev;
  57         u32 interface_version;
  58 };
  59
  60 static int __init dmi_matched(const struct dmi_system_id *dmi)
  61 {
  62         wmi_requires_smbios_request = 1;
  63         return 1;
  64 }
  65
  66 static const struct dmi_system_id dell_wmi_smbios_list[] __initconst = {
  67         {
  68                 .callback = dmi_matched,
  69                 .ident = "Dell Inspiron M5110",
  70                 .matches = {
  71                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
  72                         DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron M5110"),
  73                 },
  74         },
  75         {
  76                 .callback = dmi_matched,
  77                 .ident = "Dell Vostro V131",
  78                 .matches = {
  79                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
  80                         DMI_MATCH(DMI_PRODUCT_NAME, "Vostro V131"),
  81                 },
  82         },
  83         { }
  84 };
  85
  86 /*
  87  * Keymap for WMI events of type 0x0000
  88  *
  89  * Certain keys are flagged as KE_IGNORE. All of these are either
  90  * notifications (rather than requests for change) or are also sent
  91  * via the keyboard controller so should not be sent again.
  92  */
  93 static const struct key_entry dell_wmi_keymap_type_0000[] = {
  94         { KE_IGNORE, 0x003a, { KEY_CAPSLOCK } },
  95
  96         /* Key code is followed by brightness level */
  97         { KE_KEY,    0xe005, { KEY_BRIGHTNESSDOWN } },
  98         { KE_KEY,    0xe006, { KEY_BRIGHTNESSUP } },
  99
 100         /* Battery health status button */
 101         { KE_KEY,    0xe007, { KEY_BATTERY } },
 102
 103         /* Radio devices state change, key code is followed by other values */
 104         { KE_IGNORE, 0xe008, { KEY_RFKILL } },
 105
 106         { KE_KEY,    0xe009, { KEY_EJECTCD } },
 107
 108         /* Key code is followed by: next, active and attached devices */
 109         { KE_KEY,    0xe00b, { KEY_SWITCHVIDEOMODE } },
 110
 111         /* Key code is followed by keyboard illumination level */
 112         { KE_IGNORE, 0xe00c, { KEY_KBDILLUMTOGGLE } },
 113
 114         /* BIOS error detected */
 115         { KE_IGNORE, 0xe00d, { KEY_RESERVED } },
 116
 117         /* Battery was removed or inserted */
 118         { KE_IGNORE, 0xe00e, { KEY_RESERVED } },
 119
 120         /* Wifi Catcher */
 121         { KE_KEY,    0xe011, { KEY_WLAN } },
 122
 123         /* Ambient light sensor toggle */
 124         { KE_IGNORE, 0xe013, { KEY_RESERVED } },
 125
 126         { KE_IGNORE, 0xe020, { KEY_MUTE } },
 127
 128         /* Unknown, defined in ACPI DSDT */
 129         /* { KE_IGNORE, 0xe023, { KEY_RESERVED } }, */
 130
 131         /* Untested, Dell Instant Launch key on Inspiron 7520 */
 132         /* { KE_IGNORE, 0xe024, { KEY_RESERVED } }, */
 133
 134         /* Dell Instant Launch key */
 135         { KE_KEY,    0xe025, { KEY_PROG4 } },
 136
 137         /* Audio panel key */
 138         { KE_IGNORE, 0xe026, { KEY_RESERVED } },
 139
 140         /* LCD Display On/Off Control key */
 141         { KE_KEY,    0xe027, { KEY_DISPLAYTOGGLE } },
 142
 143         /* Untested, Multimedia key on Dell Vostro 3560 */
 144         /* { KE_IGNORE, 0xe028, { KEY_RESERVED } }, */
 145
 146         /* Dell Instant Launch key */
 147         { KE_KEY,    0xe029, { KEY_PROG4 } },
 148
 149         /* Untested, Windows Mobility Center button on Inspiron 7520 */
 150         /* { KE_IGNORE, 0xe02a, { KEY_RESERVED } }, */
 151
 152         /* Unknown, defined in ACPI DSDT */
 153         /* { KE_IGNORE, 0xe02b, { KEY_RESERVED } }, */
 154
 155         /* Untested, Dell Audio With Preset Switch button on Inspiron 7520 */
 156         /* { KE_IGNORE, 0xe02c, { KEY_RESERVED } }, */
 157
 158         { KE_IGNORE, 0xe02e, { KEY_VOLUMEDOWN } },
 159         { KE_IGNORE, 0xe030, { KEY_VOLUMEUP } },
 160         { KE_IGNORE, 0xe033, { KEY_KBDILLUMUP } },
 161         { KE_IGNORE, 0xe034, { KEY_KBDILLUMDOWN } },
 162         { KE_IGNORE, 0xe03a, { KEY_CAPSLOCK } },
 163
 164         /* NIC Link is Up */
 165         { KE_IGNORE, 0xe043, { KEY_RESERVED } },
 166
 167         /* NIC Link is Down */
 168         { KE_IGNORE, 0xe044, { KEY_RESERVED } },
 169
 170         /*
 171          * This entry is very suspicious!
 172          * Originally Matthew Garrett created this dell-wmi driver specially for
 173          * "button with a picture of a battery" which has event code 0xe045.
 174          * Later Mario Limonciello from Dell told us that event code 0xe045 is
 175          * reported by Num Lock and should be ignored because key is send also
 176          * by keyboard controller.
 177          * So for now we will ignore this event to prevent potential double
 178          * Num Lock key press.
 179          */
 180         { KE_IGNORE, 0xe045, { KEY_NUMLOCK } },
 181
 182         /* Scroll lock and also going to tablet mode on portable devices */
 183         { KE_IGNORE, 0xe046, { KEY_SCROLLLOCK } },
 184
 185         /* Untested, going from tablet mode on portable devices */
 186         /* { KE_IGNORE, 0xe047, { KEY_RESERVED } }, */
 187
 188         /* Dell Support Center key */
 189         { KE_IGNORE, 0xe06e, { KEY_RESERVED } },
 190
 191         { KE_IGNORE, 0xe0f7, { KEY_MUTE } },
 192         { KE_IGNORE, 0xe0f8, { KEY_VOLUMEDOWN } },
 193         { KE_IGNORE, 0xe0f9, { KEY_VOLUMEUP } },
 194 };
 195
 196 struct dell_bios_keymap_entry {
 197         u16 scancode;
 198         u16 keycode;
 199 };
 200
 201 struct dell_bios_hotkey_table {
 202         struct dmi_header header;
 203         struct dell_bios_keymap_entry keymap[];
 204
 205 };
 206
 207 struct dell_dmi_results {
 208         int err;
 209         int keymap_size;
 210         struct key_entry *keymap;
 211 };
 212
 213 /* Uninitialized entries here are KEY_RESERVED == 0. */
 214 static const u16 bios_to_linux_keycode[256] = {
 215         [0]     = KEY_MEDIA,
 216         [1]     = KEY_NEXTSONG,
 217         [2]     = KEY_PLAYPAUSE,
 218         [3]     = KEY_PREVIOUSSONG,
 219         [4]     = KEY_STOPCD,
 220         [5]     = KEY_UNKNOWN,
 221         [6]     = KEY_UNKNOWN,
 222         [7]     = KEY_UNKNOWN,
 223         [8]     = KEY_WWW,
 224         [9]     = KEY_UNKNOWN,
 225         [10]    = KEY_VOLUMEDOWN,
 226         [11]    = KEY_MUTE,
 227         [12]    = KEY_VOLUMEUP,
 228         [13]    = KEY_UNKNOWN,
 229         [14]    = KEY_BATTERY,
 230         [15]    = KEY_EJECTCD,
 231         [16]    = KEY_UNKNOWN,
 232         [17]    = KEY_SLEEP,
 233         [18]    = KEY_PROG1,
 234         [19]    = KEY_BRIGHTNESSDOWN,
 235         [20]    = KEY_BRIGHTNESSUP,
 236         [21]    = KEY_UNKNOWN,
 237         [22]    = KEY_KBDILLUMTOGGLE,
 238         [23]    = KEY_UNKNOWN,
 239         [24]    = KEY_SWITCHVIDEOMODE,
 240         [25]    = KEY_UNKNOWN,
 241         [26]    = KEY_UNKNOWN,
 242         [27]    = KEY_SWITCHVIDEOMODE,
 243         [28]    = KEY_UNKNOWN,
 244         [29]    = KEY_UNKNOWN,
 245         [30]    = KEY_PROG2,
 246         [31]    = KEY_UNKNOWN,
 247         [32]    = KEY_UNKNOWN,
 248         [33]    = KEY_UNKNOWN,
 249         [34]    = KEY_UNKNOWN,
 250         [35]    = KEY_UNKNOWN,
 251         [36]    = KEY_UNKNOWN,
 252         [37]    = KEY_UNKNOWN,
 253         [38]    = KEY_MICMUTE,
 254         [255]   = KEY_PROG3,
 255 };
 256
 257 /*
 258  * Keymap for WMI events of type 0x0010
 259  *
 260  * These are applied if the 0xB2 DMI hotkey table is present and doesn't
 261  * override them.
 262  */
 263 static const struct key_entry dell_wmi_keymap_type_0010[] = {
 264         /* Mic mute */
 265         { KE_KEY, 0x150, { KEY_MICMUTE } },
 266
 267         /* Fn-lock */
 268         { KE_IGNORE, 0x151, { KEY_RESERVED } },
 269
 270         /* Change keyboard illumination */
 271         { KE_IGNORE, 0x152, { KEY_KBDILLUMTOGGLE } },
 272
 273         /*
 274          * Radio disable (notify only -- there is no model for which the
 275          * WMI event is supposed to trigger an action).
 276          */
 277         { KE_IGNORE, 0x153, { KEY_RFKILL } },
 278
 279         /* RGB keyboard backlight control */
 280         { KE_IGNORE, 0x154, { KEY_RESERVED } },
 281
 282         /*
 283          * Stealth mode toggle. This will "disable all lights and sounds".
 284          * The action is performed by the BIOS and EC; the WMI event is just
 285          * a notification. On the XPS 13 9350, this is Fn+F7, and there's
 286          * a BIOS setting to enable and disable the hotkey.
 287          */
 288         { KE_IGNORE, 0x155, { KEY_RESERVED } },
 289
 290         /* Rugged magnetic dock attach/detach events */
 291         { KE_IGNORE, 0x156, { KEY_RESERVED } },
 292         { KE_IGNORE, 0x157, { KEY_RESERVED } },
 293
 294         /* Rugged programmable (P1/P2/P3 keys) */
 295         { KE_KEY,    0x850, { KEY_PROG1 } },
 296         { KE_KEY,    0x851, { KEY_PROG2 } },
 297         { KE_KEY,    0x852, { KEY_PROG3 } },
 298
 299 };
 300
 301 /*
 302  * Keymap for WMI events of type 0x0011
 303  */
 304 static const struct key_entry dell_wmi_keymap_type_0011[] = {
 305         /* Battery unplugged */
 306         { KE_IGNORE, 0xfff0, { KEY_RESERVED } },
 307
 308         /* Battery inserted */
 309         { KE_IGNORE, 0xfff1, { KEY_RESERVED } },
 310
 311         /* Keyboard backlight level changed */
 312         { KE_IGNORE, 0x01e1, { KEY_RESERVED } },
 313         { KE_IGNORE, 0x02ea, { KEY_RESERVED } },
 314         { KE_IGNORE, 0x02eb, { KEY_RESERVED } },
 315         { KE_IGNORE, 0x02ec, { KEY_RESERVED } },
 316         { KE_IGNORE, 0x02f6, { KEY_RESERVED } },
 317 };
 318
 319 static void dell_wmi_process_key(struct wmi_device *wdev, int type, int code)
 320 {
 321         struct dell_wmi_priv *priv = dev_get_drvdata(&wdev->dev);
 322         const struct key_entry *key;
 323
 324         key = sparse_keymap_entry_from_scancode(priv->input_dev,
 325                                                 (type << 16) | code);
 326         if (!key) {
 327                 pr_info("Unknown key with type 0x%04x and code 0x%04x pressed\n",
 328                         type, code);
 329                 return;
 330         }
 331
 332         pr_debug("Key with type 0x%04x and code 0x%04x pressed\n", type, code);
 333
 334         /* Don't report brightness notifications that will also come via ACPI */
 335         if ((key->keycode == KEY_BRIGHTNESSUP ||
 336              key->keycode == KEY_BRIGHTNESSDOWN) &&
 337             acpi_video_handles_brightness_key_presses())
 338                 return;
 339
 340         if (type == 0x0000 && code == 0xe025 && !wmi_requires_smbios_request)
 341                 return;
 342
 343         if (key->keycode == KEY_KBDILLUMTOGGLE)
 344                 dell_laptop_call_notifier(
 345                         DELL_LAPTOP_KBD_BACKLIGHT_BRIGHTNESS_CHANGED, NULL);
 346
 347         sparse_keymap_report_entry(priv->input_dev, key, 1, true);
 348 }
 349
 350 static void dell_wmi_notify(struct wmi_device *wdev,
 351                             union acpi_object *obj)
 352 {
 353         struct dell_wmi_priv *priv = dev_get_drvdata(&wdev->dev);
 354         u16 *buffer_entry, *buffer_end;
 355         acpi_size buffer_size;
 356         int len, i;
 357
 358         if (obj->type != ACPI_TYPE_BUFFER) {
 359                 pr_warn("bad response type %x\n", obj->type);
 360                 return;
 361         }
 362
 363         pr_debug("Received WMI event (%*ph)\n",
 364                 obj->buffer.length, obj->buffer.pointer);
 365
 366         buffer_entry = (u16 *)obj->buffer.pointer;
 367         buffer_size = obj->buffer.length/2;
 368         buffer_end = buffer_entry + buffer_size;
 369
 370         /*
 371          * BIOS/ACPI on devices with WMI interface version 0 does not clear
 372          * buffer before filling it. So next time when BIOS/ACPI send WMI event
 373          * which is smaller as previous then it contains garbage in buffer from
 374          * previous event.
 375          *
 376          * BIOS/ACPI on devices with WMI interface version 1 clears buffer and
 377          * sometimes send more events in buffer at one call.
 378          *
 379          * So to prevent reading garbage from buffer we will process only first
 380          * one event on devices with WMI interface version 0.
 381          */
 382         if (priv->interface_version == 0 && buffer_entry < buffer_end)
 383                 if (buffer_end > buffer_entry + buffer_entry[0] + 1)
 384                         buffer_end = buffer_entry + buffer_entry[0] + 1;
 385
 386         while (buffer_entry < buffer_end) {
 387
 388                 len = buffer_entry[0];
 389                 if (len == 0)
 390                         break;
 391
 392                 len++;
 393
 394                 if (buffer_entry + len > buffer_end) {
 395                         pr_warn("Invalid length of WMI event\n");
 396                         break;
 397                 }
 398
 399                 pr_debug("Process buffer (%*ph)\n", len*2, buffer_entry);
 400
 401                 switch (buffer_entry[1]) {
 402                 case 0x0000: /* One key pressed or event occurred */
 403                         if (len > 2)
 404                                 dell_wmi_process_key(wdev, 0x0000,
 405                                                      buffer_entry[2]);
 406                         /* Other entries could contain additional information */
 407                         break;
 408                 case 0x0010: /* Sequence of keys pressed */
 409                 case 0x0011: /* Sequence of events occurred */
 410                         for (i = 2; i < len; ++i)
 411                                 dell_wmi_process_key(wdev, buffer_entry[1],
 412                                                      buffer_entry[i]);
 413                         break;
 414                 default: /* Unknown event */
 415                         pr_info("Unknown WMI event type 0x%x\n",
 416                                 (int)buffer_entry[1]);
 417                         break;
 418                 }
 419
 420                 buffer_entry += len;
 421
 422         }
 423
 424 }
 425
 426 static bool have_scancode(u32 scancode, const struct key_entry *keymap, int len)
 427 {
 428         int i;
 429
 430         for (i = 0; i < len; i++)
 431                 if (keymap[i].code == scancode)
 432                         return true;
 433
 434         return false;
 435 }
 436
 437 static void handle_dmi_entry(const struct dmi_header *dm, void *opaque)
 438 {
 439         struct dell_dmi_results *results = opaque;
 440         struct dell_bios_hotkey_table *table;
 441         int hotkey_num, i, pos = 0;
 442         struct key_entry *keymap;
 443
 444         if (results->err || results->keymap)
 445                 return;         /* We already found the hotkey table. */
 446
 447         /* The Dell hotkey table is type 0xB2.  Scan until we find it. */
 448         if (dm->type != 0xb2)
 449                 return;
 450
 451         table = container_of(dm, struct dell_bios_hotkey_table, header);
 452
 453         hotkey_num = (table->header.length -
 454                       sizeof(struct dell_bios_hotkey_table)) /
 455                                 sizeof(struct dell_bios_keymap_entry);
 456         if (hotkey_num < 1) {
 457                 /*
 458                  * Historically, dell-wmi would ignore a DMI entry of
 459                  * fewer than 7 bytes.  Sizes between 4 and 8 bytes are
 460                  * nonsensical (both the header and all entries are 4
 461                  * bytes), so we approximate the old behavior by
 462                  * ignoring tables with fewer than one entry.
 463                  */
 464                 return;
 465         }
 466
 467         keymap = kcalloc(hotkey_num, sizeof(struct key_entry), GFP_KERNEL);
 468         if (!keymap) {
 469                 results->err = -ENOMEM;
 470                 return;
 471         }
 472
 473         for (i = 0; i < hotkey_num; i++) {
 474                 const struct dell_bios_keymap_entry *bios_entry =
 475                                         &table->keymap[i];
 476
 477                 /* Uninitialized entries are 0 aka KEY_RESERVED. */
 478                 u16 keycode = (bios_entry->keycode <
 479                                ARRAY_SIZE(bios_to_linux_keycode)) ?
 480                         bios_to_linux_keycode[bios_entry->keycode] :
 481                         KEY_RESERVED;
 482
 483                 /*
 484                  * Log if we find an entry in the DMI table that we don't
 485                  * understand.  If this happens, we should figure out what
 486                  * the entry means and add it to bios_to_linux_keycode.
 487                  */
 488                 if (keycode == KEY_RESERVED) {
 489                         pr_info("firmware scancode 0x%x maps to unrecognized keycode 0x%x\n",
 490                                 bios_entry->scancode, bios_entry->keycode);
 491                         continue;
 492                 }
 493
 494                 if (keycode == KEY_KBDILLUMTOGGLE)
 495                         keymap[pos].type = KE_IGNORE;
 496                 else
 497                         keymap[pos].type = KE_KEY;
 498                 keymap[pos].code = bios_entry->scancode;
 499                 keymap[pos].keycode = keycode;
 500
 501                 pos++;
 502         }
 503
 504         results->keymap = keymap;
 505         results->keymap_size = pos;
 506 }
 507
 508 static int dell_wmi_input_setup(struct wmi_device *wdev)
 509 {
 510         struct dell_wmi_priv *priv = dev_get_drvdata(&wdev->dev);
 511         struct dell_dmi_results dmi_results = {};
 512         struct key_entry *keymap;
 513         int err, i, pos = 0;
 514
 515         priv->input_dev = input_allocate_device();
 516         if (!priv->input_dev)
 517                 return -ENOMEM;
 518
 519         priv->input_dev->name = "Dell WMI hotkeys";
 520         priv->input_dev->id.bustype = BUS_HOST;
 521         priv->input_dev->dev.parent = &wdev->dev;
 522
 523         if (dmi_walk(handle_dmi_entry, &dmi_results)) {
 524                 /*
 525                  * Historically, dell-wmi ignored dmi_walk errors.  A failure
 526                  * is certainly surprising, but it probably just indicates
 527                  * a very old laptop.
 528                  */
 529                 pr_warn("no DMI; using the old-style hotkey interface\n");
 530         }
 531
 532         if (dmi_results.err) {
 533                 err = dmi_results.err;
 534                 goto err_free_dev;
 535         }
 536
 537         keymap = kcalloc(dmi_results.keymap_size +
 538                          ARRAY_SIZE(dell_wmi_keymap_type_0000) +
 539                          ARRAY_SIZE(dell_wmi_keymap_type_0010) +
 540                          ARRAY_SIZE(dell_wmi_keymap_type_0011) +
 541                          1,
 542                          sizeof(struct key_entry), GFP_KERNEL);
 543         if (!keymap) {
 544                 kfree(dmi_results.keymap);
 545                 err = -ENOMEM;
 546                 goto err_free_dev;
 547         }
 548
 549         /* Append table with events of type 0x0010 which comes from DMI */
 550         for (i = 0; i < dmi_results.keymap_size; i++) {
 551                 keymap[pos] = dmi_results.keymap[i];
 552                 keymap[pos].code |= (0x0010 << 16);
 553                 pos++;
 554         }
 555
 556         kfree(dmi_results.keymap);
 557
 558         /* Append table with extra events of type 0x0010 which are not in DMI */
 559         for (i = 0; i < ARRAY_SIZE(dell_wmi_keymap_type_0010); i++) {
 560                 const struct key_entry *entry = &dell_wmi_keymap_type_0010[i];
 561
 562                 /*
 563                  * Check if we've already found this scancode.  This takes
 564                  * quadratic time, but it doesn't matter unless the list
 565                  * of extra keys gets very long.
 566                  */
 567                 if (dmi_results.keymap_size &&
 568                     have_scancode(entry->code | (0x0010 << 16),
 569                                   keymap, dmi_results.keymap_size)
 570                    )
 571                         continue;
 572
 573                 keymap[pos] = *entry;
 574                 keymap[pos].code |= (0x0010 << 16);
 575                 pos++;
 576         }
 577
 578         /* Append table with events of type 0x0011 */
 579         for (i = 0; i < ARRAY_SIZE(dell_wmi_keymap_type_0011); i++) {
 580                 keymap[pos] = dell_wmi_keymap_type_0011[i];
 581                 keymap[pos].code |= (0x0011 << 16);
 582                 pos++;
 583         }
 584
 585         /*
 586          * Now append also table with "legacy" events of type 0x0000. Some of
 587          * them are reported also on laptops which have scancodes in DMI.
 588          */
 589         for (i = 0; i < ARRAY_SIZE(dell_wmi_keymap_type_0000); i++) {
 590                 keymap[pos] = dell_wmi_keymap_type_0000[i];
 591                 pos++;
 592         }
 593
 594         keymap[pos].type = KE_END;
 595
 596         err = sparse_keymap_setup(priv->input_dev, keymap, NULL);
 597         /*
 598          * Sparse keymap library makes a copy of keymap so we don't need the
 599          * original one that was allocated.
 600          */
 601         kfree(keymap);
 602         if (err)
 603                 goto err_free_dev;
 604
 605         err = input_register_device(priv->input_dev);
 606         if (err)
 607                 goto err_free_dev;
 608
 609         return 0;
 610
 611  err_free_dev:
 612         input_free_device(priv->input_dev);
 613         return err;
 614 }
 615
 616 static void dell_wmi_input_destroy(struct wmi_device *wdev)
 617 {
 618         struct dell_wmi_priv *priv = dev_get_drvdata(&wdev->dev);
 619
 620         input_unregister_device(priv->input_dev);
 621 }
 622
 623 /*
 624  * According to Dell SMBIOS documentation:
 625  *
 626  * 17  3  Application Program Registration
 627  *
 628  *     cbArg1 Application ID 1 = 0x00010000
 629  *     cbArg2 Application ID 2
 630  *            QUICKSET/DCP = 0x51534554 "QSET"
 631  *            ALS Driver   = 0x416c7353 "AlsS"
 632  *            Latitude ON  = 0x4c6f6e52 "LonR"
 633  *     cbArg3 Application version or revision number
 634  *     cbArg4 0 = Unregister application
 635  *            1 = Register application
 636  *     cbRes1 Standard return codes (0, -1, -2)
 637  */
 638
 639 static int dell_wmi_events_set_enabled(bool enable)
 640 {
 641         struct calling_interface_buffer *buffer;
 642         int ret;
 643
 644         buffer = kzalloc(sizeof(struct calling_interface_buffer), GFP_KERNEL);
 645         if (!buffer)
 646                 return -ENOMEM;
 647         buffer->cmd_class = CLASS_INFO;
 648         buffer->cmd_select = SELECT_APP_REGISTRATION;
 649         buffer->input[0] = 0x10000;
 650         buffer->input[1] = 0x51534554;
 651         buffer->input[3] = enable;
 652         ret = dell_smbios_call(buffer);
 653         if (ret == 0)
 654                 ret = buffer->output[0];
 655         kfree(buffer);
 656
 657         return dell_smbios_error(ret);
 658 }
 659
 660 static int dell_wmi_probe(struct wmi_device *wdev)
 661 {
 662         struct dell_wmi_priv *priv;
 663         int ret;
 664
 665         ret = dell_wmi_get_descriptor_valid();
 666         if (ret)
 667                 return ret;
 668
 669         priv = devm_kzalloc(
 670                 &wdev->dev, sizeof(struct dell_wmi_priv), GFP_KERNEL);
 671         if (!priv)
 672                 return -ENOMEM;
 673         dev_set_drvdata(&wdev->dev, priv);
 674
 675         if (!dell_wmi_get_interface_version(&priv->interface_version))
 676                 return -EPROBE_DEFER;
 677
 678         return dell_wmi_input_setup(wdev);
 679 }
 680
 681 static int dell_wmi_remove(struct wmi_device *wdev)
 682 {
 683         dell_wmi_input_destroy(wdev);
 684         return 0;
 685 }
 686 static const struct wmi_device_id dell_wmi_id_table[] = {
 687         { .guid_string = DELL_EVENT_GUID },
 688         { },
 689 };
 690
 691 static struct wmi_driver dell_wmi_driver = {
 692         .driver = {
 693                 .name = "dell-wmi",
 694         },
 695         .id_table = dell_wmi_id_table,
 696         .probe = dell_wmi_probe,
 697         .remove = dell_wmi_remove,
 698         .notify = dell_wmi_notify,
 699 };
 700
 701 static int __init dell_wmi_init(void)
 702 {
 703         int err;
 704
 705         dmi_check_system(dell_wmi_smbios_list);
 706
 707         if (wmi_requires_smbios_request) {
 708                 err = dell_wmi_events_set_enabled(true);
 709                 if (err) {
 710                         pr_err("Failed to enable WMI events\n");
 711                         return err;
 712                 }
 713         }
 714
 715         return wmi_driver_register(&dell_wmi_driver);
 716 }
 717 module_init(dell_wmi_init);
 718
 719 static void __exit dell_wmi_exit(void)
 720 {
 721         if (wmi_requires_smbios_request)
 722                 dell_wmi_events_set_enabled(false);
 723
 724         wmi_driver_unregister(&dell_wmi_driver);
 725 }
 726 module_exit(dell_wmi_exit);