drivers/acpi/ec.c

   1 /*
   2  *  acpi_ec.c - ACPI Embedded Controller Driver ($Revision: 36 $)
   3  *
   4  *  Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
   5  *  Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
   6  *
   7  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   8  *
   9  *  This program is free software; you can redistribute it and/or modify
  10  *  it under the terms of the GNU General Public License as published by
  11  *  the Free Software Foundation; either version 2 of the License, or (at
  12  *  your option) any later version.
  13  *
  14  *  This program is distributed in the hope that it will be useful, but
  15  *  WITHOUT ANY WARRANTY; without even the implied warranty of
  16  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  17  *  General Public License for more details.
  18  *
  19  *  You should have received a copy of the GNU General Public License along
  20  *  with this program; if not, write to the Free Software Foundation, Inc.,
  21  *  59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
  22  *
  23  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  24  */
  25
  26 #include <linux/kernel.h>
  27 #include <linux/module.h>
  28 #include <linux/init.h>
  29 #include <linux/types.h>
  30 #include <linux/delay.h>
  31 #include <linux/compatmac.h>
  32 #include <linux/proc_fs.h>
  33 #include <asm/io.h>
  34 #include <acpi/acpi_bus.h>
  35 #include <acpi/acpi_drivers.h>
  36 #include <acpi/actypes.h>
  37
  38 #define _COMPONENT              ACPI_EC_COMPONENT
  39 ACPI_MODULE_NAME                ("acpi_ec")
  40
  41 #define PREFIX                  "ACPI: "
  42
  43
  44 #define ACPI_EC_FLAG_OBF        0x01    /* Output buffer full */
  45 #define ACPI_EC_FLAG_IBF        0x02    /* Input buffer full */
  46 #define ACPI_EC_FLAG_SCI        0x20    /* EC-SCI occurred */
  47
  48 #define ACPI_EC_EVENT_OBF       0x01    /* Output buffer full */
  49 #define ACPI_EC_EVENT_IBE       0x02    /* Input buffer empty */
  50
  51 #define ACPI_EC_UDELAY          100     /* Poll @ 100us increments */
  52 #define ACPI_EC_UDELAY_COUNT    1000    /* Wait 10ms max. during EC ops */
  53 #define ACPI_EC_UDELAY_GLK      1000    /* Wait 1ms max. to get global lock */
  54
  55 #define ACPI_EC_COMMAND_READ    0x80
  56 #define ACPI_EC_COMMAND_WRITE   0x81
  57 #define ACPI_EC_COMMAND_QUERY   0x84
  58
  59 static int acpi_ec_add (struct acpi_device *device);
  60 static int acpi_ec_remove (struct acpi_device *device, int type);
  61 static int acpi_ec_start (struct acpi_device *device);
  62 static int acpi_ec_stop (struct acpi_device *device, int type);
  63
  64 static struct acpi_driver acpi_ec_driver = {
  65         .name =         ACPI_EC_DRIVER_NAME,
  66         .class =        ACPI_EC_CLASS,
  67         .ids =          ACPI_EC_HID,
  68         .ops =          {
  69                                 .add =          acpi_ec_add,
  70                                 .remove =       acpi_ec_remove,
  71                                 .start =        acpi_ec_start,
  72                                 .stop =         acpi_ec_stop,
  73                         },
  74 };
  75
  76 struct acpi_ec {
  77         acpi_handle                     handle;
  78         unsigned long                   uid;
  79         unsigned long                   gpe_bit;
  80         struct acpi_generic_address     status_addr;
  81         struct acpi_generic_address     command_addr;
  82         struct acpi_generic_address     data_addr;
  83         unsigned long                   global_lock;
  84         spinlock_t                      lock;
  85 };
  86
  87 /* If we find an EC via the ECDT, we need to keep a ptr to its context */
  88 static struct acpi_ec   *ec_ecdt;
  89
  90 /* External interfaces use first EC only, so remember */
  91 static struct acpi_device *first_ec;
  92
  93 /* --------------------------------------------------------------------------
  94                              Transaction Management
  95    -------------------------------------------------------------------------- */
  96
  97 static int
  98 acpi_ec_wait (
  99         struct acpi_ec          *ec,
 100         u8                      event)
 101 {
 102         u32                     acpi_ec_status = 0;
 103         u32                     i = ACPI_EC_UDELAY_COUNT;
 104
 105         if (!ec)
 106                 return -EINVAL;
 107
 108         /* Poll the EC status register waiting for the event to occur. */
 109         switch (event) {
 110         case ACPI_EC_EVENT_OBF:
 111                 do {
 112                         acpi_hw_low_level_read(8, &acpi_ec_status, &ec->status_addr);
 113                         if (acpi_ec_status & ACPI_EC_FLAG_OBF)
 114                                 return 0;
 115                         udelay(ACPI_EC_UDELAY);
 116                 } while (--i>0);
 117                 break;
 118         case ACPI_EC_EVENT_IBE:
 119                 do {
 120                         acpi_hw_low_level_read(8, &acpi_ec_status, &ec->status_addr);
 121                         if (!(acpi_ec_status & ACPI_EC_FLAG_IBF))
 122                                 return 0;
 123                         udelay(ACPI_EC_UDELAY);
 124                 } while (--i>0);
 125                 break;
 126         default:
 127                 return -EINVAL;
 128         }
 129
 130         return -ETIME;
 131 }
 132
 133
 134 static int
 135 acpi_ec_read (
 136         struct acpi_ec          *ec,
 137         u8                      address,
 138         u32                     *data)
 139 {
 140         acpi_status             status = AE_OK;
 141         int                     result = 0;
 142         unsigned long           flags = 0;
 143         u32                     glk = 0;
 144
 145         ACPI_FUNCTION_TRACE("acpi_ec_read");
 146
 147         if (!ec || !data)
 148                 return_VALUE(-EINVAL);
 149
 150         *data = 0;
 151
 152         if (ec->global_lock) {
 153                 status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk);
 154                 if (ACPI_FAILURE(status))
 155                         return_VALUE(-ENODEV);
 156         }
 157
 158         spin_lock_irqsave(&ec->lock, flags);
 159
 160         acpi_hw_low_level_write(8, ACPI_EC_COMMAND_READ, &ec->command_addr);
 161         result = acpi_ec_wait(ec, ACPI_EC_EVENT_IBE);
 162         if (result)
 163                 goto end;
 164
 165         acpi_hw_low_level_write(8, address, &ec->data_addr);
 166         result = acpi_ec_wait(ec, ACPI_EC_EVENT_OBF);
 167         if (result)
 168                 goto end;
 169
 170
 171         acpi_hw_low_level_read(8, data, &ec->data_addr);
 172
 173         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Read [%02x] from address [%02x]\n",
 174                 *data, address));
 175
 176 end:
 177         spin_unlock_irqrestore(&ec->lock, flags);
 178
 179         if (ec->global_lock)
 180                 acpi_release_global_lock(glk);
 181
 182         return_VALUE(result);
 183 }
 184
 185
 186 static int
 187 acpi_ec_write (
 188         struct acpi_ec          *ec,
 189         u8                      address,
 190         u8                      data)
 191 {
 192         int                     result = 0;
 193         acpi_status             status = AE_OK;
 194         unsigned long           flags = 0;
 195         u32                     glk = 0;
 196
 197         ACPI_FUNCTION_TRACE("acpi_ec_write");
 198
 199         if (!ec)
 200                 return_VALUE(-EINVAL);
 201
 202         if (ec->global_lock) {
 203                 status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk);
 204                 if (ACPI_FAILURE(status))
 205                         return_VALUE(-ENODEV);
 206         }
 207
 208         spin_lock_irqsave(&ec->lock, flags);
 209
 210         acpi_hw_low_level_write(8, ACPI_EC_COMMAND_WRITE, &ec->command_addr);
 211         result = acpi_ec_wait(ec, ACPI_EC_EVENT_IBE);
 212         if (result)
 213                 goto end;
 214
 215         acpi_hw_low_level_write(8, address, &ec->data_addr);
 216         result = acpi_ec_wait(ec, ACPI_EC_EVENT_IBE);
 217         if (result)
 218                 goto end;
 219
 220         acpi_hw_low_level_write(8, data, &ec->data_addr);
 221         result = acpi_ec_wait(ec, ACPI_EC_EVENT_IBE);
 222         if (result)
 223                 goto end;
 224
 225         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Wrote [%02x] to address [%02x]\n",
 226                 data, address));
 227
 228 end:
 229         spin_unlock_irqrestore(&ec->lock, flags);
 230
 231         if (ec->global_lock)
 232                 acpi_release_global_lock(glk);
 233
 234         return_VALUE(result);
 235 }
 236
 237 /*
 238  * Externally callable EC access functions. For now, assume 1 EC only
 239  */
 240 int
 241 ec_read(u8 addr, u8 *val)
 242 {
 243         struct acpi_ec *ec;
 244         int err;
 245         u32 temp_data;
 246
 247         if (!first_ec)
 248                 return -ENODEV;
 249
 250         ec = acpi_driver_data(first_ec);
 251
 252         err = acpi_ec_read(ec, addr, &temp_data);
 253
 254         if (!err) {
 255                 *val = temp_data;
 256                 return 0;
 257         }
 258         else
 259                 return err;
 260 }
 261
 262 int
 263 ec_write(u8 addr, u8 val)
 264 {
 265         struct acpi_ec *ec;
 266         int err;
 267
 268         if (!first_ec)
 269                 return -ENODEV;
 270
 271         ec = acpi_driver_data(first_ec);
 272
 273         err = acpi_ec_write(ec, addr, val);
 274
 275         return err;
 276 }
 277
 278
 279 static int
 280 acpi_ec_query (
 281         struct acpi_ec          *ec,
 282         u32                     *data)
 283 {
 284         int                     result = 0;
 285         acpi_status             status = AE_OK;
 286         unsigned long           flags = 0;
 287         u32                     glk = 0;
 288
 289         ACPI_FUNCTION_TRACE("acpi_ec_query");
 290
 291         if (!ec || !data)
 292                 return_VALUE(-EINVAL);
 293
 294         *data = 0;
 295
 296         if (ec->global_lock) {
 297                 status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk);
 298                 if (ACPI_FAILURE(status))
 299                         return_VALUE(-ENODEV);
 300         }
 301
 302         /*
 303          * Query the EC to find out which _Qxx method we need to evaluate.
 304          * Note that successful completion of the query causes the ACPI_EC_SCI
 305          * bit to be cleared (and thus clearing the interrupt source).
 306          */
 307         spin_lock_irqsave(&ec->lock, flags);
 308
 309         acpi_hw_low_level_write(8, ACPI_EC_COMMAND_QUERY, &ec->command_addr);
 310         result = acpi_ec_wait(ec, ACPI_EC_EVENT_OBF);
 311         if (result)
 312                 goto end;
 313
 314         acpi_hw_low_level_read(8, data, &ec->data_addr);
 315         if (!*data)
 316                 result = -ENODATA;
 317
 318 end:
 319         spin_unlock_irqrestore(&ec->lock, flags);
 320
 321         if (ec->global_lock)
 322                 acpi_release_global_lock(glk);
 323
 324         return_VALUE(result);
 325 }
 326
 327
 328 /* --------------------------------------------------------------------------
 329                                 Event Management
 330    -------------------------------------------------------------------------- */
 331
 332 struct acpi_ec_query_data {
 333         acpi_handle             handle;
 334         u8                      data;
 335 };
 336
 337 static void
 338 acpi_ec_gpe_query (
 339         void                    *ec_cxt)
 340 {
 341         struct acpi_ec          *ec = (struct acpi_ec *) ec_cxt;
 342         u32                     value = 0;
 343         unsigned long           flags = 0;
 344         static char             object_name[5] = {'_','Q','0','0','\0'};
 345         const char              hex[] = {'0','1','2','3','4','5','6','7',
 346                                          '8','9','A','B','C','D','E','F'};
 347
 348         ACPI_FUNCTION_TRACE("acpi_ec_gpe_query");
 349
 350         if (!ec_cxt)
 351                 goto end;
 352
 353         spin_lock_irqsave(&ec->lock, flags);
 354         acpi_hw_low_level_read(8, &value, &ec->command_addr);
 355         spin_unlock_irqrestore(&ec->lock, flags);
 356
 357         /* TBD: Implement asynch events!
 358          * NOTE: All we care about are EC-SCI's.  Other EC events are
 359          * handled via polling (yuck!).  This is because some systems
 360          * treat EC-SCIs as level (versus EDGE!) triggered, preventing
 361          *  a purely interrupt-driven approach (grumble, grumble).
 362          */
 363         if (!(value & ACPI_EC_FLAG_SCI))
 364                 goto end;
 365
 366         if (acpi_ec_query(ec, &value))
 367                 goto end;
 368
 369         object_name[2] = hex[((value >> 4) & 0x0F)];
 370         object_name[3] = hex[(value & 0x0F)];
 371
 372         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Evaluating %s\n", object_name));
 373
 374         acpi_evaluate_object(ec->handle, object_name, NULL, NULL);
 375
 376 end:
 377         acpi_enable_gpe(NULL, ec->gpe_bit, ACPI_NOT_ISR);
 378 }
 379
 380 static void
 381 acpi_ec_gpe_handler (
 382         void                    *data)
 383 {
 384         acpi_status             status = AE_OK;
 385         struct acpi_ec          *ec = (struct acpi_ec *) data;
 386
 387         if (!ec)
 388                 return;
 389
 390         acpi_disable_gpe(NULL, ec->gpe_bit, ACPI_ISR);
 391
 392         status = acpi_os_queue_for_execution(OSD_PRIORITY_GPE,
 393                 acpi_ec_gpe_query, ec);
 394 }
 395
 396 /* --------------------------------------------------------------------------
 397                              Address Space Management
 398    -------------------------------------------------------------------------- */
 399
 400 static acpi_status
 401 acpi_ec_space_setup (
 402         acpi_handle             region_handle,
 403         u32                     function,
 404         void                    *handler_context,
 405         void                    **return_context)
 406 {
 407         /*
 408          * The EC object is in the handler context and is needed
 409          * when calling the acpi_ec_space_handler.
 410          */
 411         if(function == ACPI_REGION_DEACTIVATE)
 412                 *return_context = NULL;
 413         else
 414                 *return_context = handler_context;
 415
 416         return AE_OK;
 417 }
 418
 419
 420 static acpi_status
 421 acpi_ec_space_handler (
 422         u32                     function,
 423         acpi_physical_address   address,
 424         u32                     bit_width,
 425         acpi_integer            *value,
 426         void                    *handler_context,
 427         void                    *region_context)
 428 {
 429         int                     result = 0;
 430         struct acpi_ec          *ec = NULL;
 431         u32                     temp = 0;
 432
 433         ACPI_FUNCTION_TRACE("acpi_ec_space_handler");
 434
 435         if ((address > 0xFF) || (bit_width != 8) || !value || !handler_context)
 436                 return_VALUE(AE_BAD_PARAMETER);
 437
 438         ec = (struct acpi_ec *) handler_context;
 439
 440         switch (function) {
 441         case ACPI_READ:
 442                 result = acpi_ec_read(ec, (u8) address, &temp);
 443                 *value = (acpi_integer) temp;
 444                 break;
 445         case ACPI_WRITE:
 446                 result = acpi_ec_write(ec, (u8) address, (u8) *value);
 447                 break;
 448         default:
 449                 result = -EINVAL;
 450                 break;
 451         }
 452
 453         switch (result) {
 454         case -EINVAL:
 455                 return_VALUE(AE_BAD_PARAMETER);
 456                 break;
 457         case -ENODEV:
 458                 return_VALUE(AE_NOT_FOUND);
 459                 break;
 460         case -ETIME:
 461                 return_VALUE(AE_TIME);
 462                 break;
 463         default:
 464                 return_VALUE(AE_OK);
 465         }
 466
 467 }
 468
 469
 470 /* --------------------------------------------------------------------------
 471                               FS Interface (/proc)
 472    -------------------------------------------------------------------------- */
 473
 474 struct proc_dir_entry           *acpi_ec_dir;
 475
 476
 477 static int
 478 acpi_ec_read_info (
 479         char                    *page,
 480         char                    **start,
 481         off_t                   off,
 482         int                     count,
 483         int                     *eof,
 484         void                    *data)
 485 {
 486         struct acpi_ec          *ec = (struct acpi_ec *) data;
 487         char                    *p = page;
 488         int                     len = 0;
 489
 490         ACPI_FUNCTION_TRACE("acpi_ec_read_info");
 491
 492         if (!ec || (off != 0))
 493                 goto end;
 494
 495         p += sprintf(p, "gpe bit:                 0x%02x\n",
 496                 (u32) ec->gpe_bit);
 497         p += sprintf(p, "ports:                   0x%02x, 0x%02x\n",
 498                 (u32) ec->status_addr.address, (u32) ec->data_addr.address);
 499         p += sprintf(p, "use global lock:         %s\n",
 500                 ec->global_lock?"yes":"no");
 501
 502 end:
 503         len = (p - page);
 504         if (len <= off+count) *eof = 1;
 505         *start = page + off;
 506         len -= off;
 507         if (len>count) len = count;
 508         if (len<0) len = 0;
 509
 510         return_VALUE(len);
 511 }
 512
 513
 514 static int
 515 acpi_ec_add_fs (
 516         struct acpi_device      *device)
 517 {
 518         struct proc_dir_entry   *entry = NULL;
 519
 520         ACPI_FUNCTION_TRACE("acpi_ec_add_fs");
 521
 522         if (!acpi_device_dir(device)) {
 523                 acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device),
 524                         acpi_ec_dir);
 525                 if (!acpi_device_dir(device))
 526                         return_VALUE(-ENODEV);
 527         }
 528
 529         entry = create_proc_read_entry(ACPI_EC_FILE_INFO, S_IRUGO,
 530                 acpi_device_dir(device), acpi_ec_read_info,
 531                 acpi_driver_data(device));
 532         if (!entry)
 533                 ACPI_DEBUG_PRINT((ACPI_DB_WARN,
 534                         "Unable to create '%s' fs entry\n",
 535                         ACPI_EC_FILE_INFO));
 536
 537         return_VALUE(0);
 538 }
 539
 540
 541 static int
 542 acpi_ec_remove_fs (
 543         struct acpi_device      *device)
 544 {
 545         ACPI_FUNCTION_TRACE("acpi_ec_remove_fs");
 546
 547         if (acpi_device_dir(device)) {
 548                 remove_proc_entry(ACPI_EC_FILE_INFO, acpi_device_dir(device));
 549                 remove_proc_entry(acpi_device_bid(device), acpi_ec_dir);
 550                 acpi_device_dir(device) = NULL;
 551         }
 552
 553         return_VALUE(0);
 554 }
 555
 556
 557 /* --------------------------------------------------------------------------
 558                                Driver Interface
 559    -------------------------------------------------------------------------- */
 560
 561 static int
 562 acpi_ec_add (
 563         struct acpi_device      *device)
 564 {
 565         int                     result = 0;
 566         acpi_status             status = AE_OK;
 567         struct acpi_ec          *ec = NULL;
 568         unsigned long           uid;
 569
 570         ACPI_FUNCTION_TRACE("acpi_ec_add");
 571
 572         if (!device)
 573                 return_VALUE(-EINVAL);
 574
 575         ec = kmalloc(sizeof(struct acpi_ec), GFP_KERNEL);
 576         if (!ec)
 577                 return_VALUE(-ENOMEM);
 578         memset(ec, 0, sizeof(struct acpi_ec));
 579
 580         ec->handle = device->handle;
 581         ec->uid = -1;
 582         ec->lock = SPIN_LOCK_UNLOCKED;
 583         sprintf(acpi_device_name(device), "%s", ACPI_EC_DEVICE_NAME);
 584         sprintf(acpi_device_class(device), "%s", ACPI_EC_CLASS);
 585         acpi_driver_data(device) = ec;
 586
 587         /* Use the global lock for all EC transactions? */
 588         acpi_evaluate_integer(ec->handle, "_GLK", NULL, &ec->global_lock);
 589
 590         /* If our UID matches the UID for the ECDT-enumerated EC,
 591            we now have the *real* EC info, so kill the makeshift one.*/
 592         acpi_evaluate_integer(ec->handle, "_UID", NULL, &uid);
 593         if (ec_ecdt && ec_ecdt->uid == uid) {
 594                 acpi_remove_address_space_handler(ACPI_ROOT_OBJECT,
 595                         ACPI_ADR_SPACE_EC, &acpi_ec_space_handler);
 596
 597                 acpi_remove_gpe_handler(NULL, ec_ecdt->gpe_bit, &acpi_ec_gpe_handler);
 598
 599                 kfree(ec_ecdt);
 600         }
 601
 602         /* Get GPE bit assignment (EC events). */
 603         /* TODO: Add support for _GPE returning a package */
 604         status = acpi_evaluate_integer(ec->handle, "_GPE", NULL, &ec->gpe_bit);
 605         if (ACPI_FAILURE(status)) {
 606                 ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
 607                         "Error obtaining GPE bit assignment\n"));
 608                 result = -ENODEV;
 609                 goto end;
 610         }
 611
 612         result = acpi_ec_add_fs(device);
 613         if (result)
 614                 goto end;
 615
 616         printk(KERN_INFO PREFIX "%s [%s] (gpe %d)\n",
 617                 acpi_device_name(device), acpi_device_bid(device),
 618                 (u32) ec->gpe_bit);
 619
 620         if (!first_ec)
 621                 first_ec = device;
 622
 623 end:
 624         if (result)
 625                 kfree(ec);
 626
 627         return_VALUE(result);
 628 }
 629
 630
 631 static int
 632 acpi_ec_remove (
 633         struct acpi_device      *device,
 634         int                     type)
 635 {
 636         struct acpi_ec          *ec = NULL;
 637
 638         ACPI_FUNCTION_TRACE("acpi_ec_remove");
 639
 640         if (!device)
 641                 return_VALUE(-EINVAL);
 642
 643         ec = acpi_driver_data(device);
 644
 645         acpi_ec_remove_fs(device);
 646
 647         kfree(ec);
 648
 649         return_VALUE(0);
 650 }
 651
 652
 653 static acpi_status
 654 acpi_ec_io_ports (
 655         struct acpi_resource    *resource,
 656         void                    *context)
 657 {
 658         struct acpi_ec          *ec = (struct acpi_ec *) context;
 659         struct acpi_generic_address *addr;
 660
 661         if (resource->id != ACPI_RSTYPE_IO) {
 662                 return AE_OK;
 663         }
 664
 665         /*
 666          * The first address region returned is the data port, and
 667          * the second address region returned is the status/command
 668          * port.
 669          */
 670         if (ec->data_addr.register_bit_width == 0) {
 671                 addr = &ec->data_addr;
 672         } else if (ec->command_addr.register_bit_width == 0) {
 673                 addr = &ec->command_addr;
 674         } else {
 675                 return AE_CTRL_TERMINATE;
 676         }
 677
 678         addr->address_space_id = ACPI_ADR_SPACE_SYSTEM_IO;
 679         addr->register_bit_width = 8;
 680         addr->register_bit_offset = 0;
 681         addr->address = resource->data.io.min_base_address;
 682
 683         return AE_OK;
 684 }
 685
 686
 687 static int
 688 acpi_ec_start (
 689         struct acpi_device      *device)
 690 {
 691         acpi_status             status = AE_OK;
 692         struct acpi_ec          *ec = NULL;
 693
 694         ACPI_FUNCTION_TRACE("acpi_ec_start");
 695
 696         if (!device)
 697                 return_VALUE(-EINVAL);
 698
 699         ec = acpi_driver_data(device);
 700
 701         if (!ec)
 702                 return_VALUE(-EINVAL);
 703
 704         /*
 705          * Get I/O port addresses. Convert to GAS format.
 706          */
 707         status = acpi_walk_resources(ec->handle, METHOD_NAME__CRS,
 708                 acpi_ec_io_ports, ec);
 709         if (ACPI_FAILURE(status) || ec->command_addr.register_bit_width == 0) {
 710                 ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Error getting I/O port addresses"));
 711                 return_VALUE(-ENODEV);
 712         }
 713
 714         ec->status_addr = ec->command_addr;
 715
 716         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "gpe=0x%02x, ports=0x%2x,0x%2x\n",
 717                 (u32) ec->gpe_bit, (u32) ec->command_addr.address,
 718                 (u32) ec->data_addr.address));
 719
 720         /*
 721          * Install GPE handler
 722          */
 723         status = acpi_install_gpe_handler(NULL, ec->gpe_bit,
 724                 ACPI_GPE_EDGE_TRIGGERED, &acpi_ec_gpe_handler, ec);
 725         if (ACPI_FAILURE(status)) {
 726                 return_VALUE(-ENODEV);
 727         }
 728
 729         status = acpi_install_address_space_handler (ec->handle,
 730                         ACPI_ADR_SPACE_EC, &acpi_ec_space_handler,
 731                         &acpi_ec_space_setup, ec);
 732         if (ACPI_FAILURE(status)) {
 733                 acpi_remove_gpe_handler(NULL, ec->gpe_bit, &acpi_ec_gpe_handler);
 734                 return_VALUE(-ENODEV);
 735         }
 736
 737         return_VALUE(AE_OK);
 738 }
 739
 740
 741 static int
 742 acpi_ec_stop (
 743         struct acpi_device      *device,
 744         int                     type)
 745 {
 746         acpi_status             status = AE_OK;
 747         struct acpi_ec          *ec = NULL;
 748
 749         ACPI_FUNCTION_TRACE("acpi_ec_stop");
 750
 751         if (!device)
 752                 return_VALUE(-EINVAL);
 753
 754         ec = acpi_driver_data(device);
 755
 756         status = acpi_remove_address_space_handler(ec->handle,
 757                 ACPI_ADR_SPACE_EC, &acpi_ec_space_handler);
 758         if (ACPI_FAILURE(status))
 759                 return_VALUE(-ENODEV);
 760
 761         status = acpi_remove_gpe_handler(NULL, ec->gpe_bit, &acpi_ec_gpe_handler);
 762         if (ACPI_FAILURE(status))
 763                 return_VALUE(-ENODEV);
 764
 765         return_VALUE(0);
 766 }
 767
 768
 769 int __init
 770 acpi_ec_ecdt_probe (void)
 771 {
 772         acpi_status             status;
 773         struct acpi_table_ecdt  *ecdt_ptr;
 774
 775         status = acpi_get_firmware_table("ECDT", 1, ACPI_LOGICAL_ADDRESSING,
 776                 (struct acpi_table_header **) &ecdt_ptr);
 777         if (ACPI_FAILURE(status))
 778                 return 0;
 779
 780         printk(KERN_INFO PREFIX "Found ECDT\n");
 781
 782          /*
 783          * Generate a temporary ec context to use until the namespace is scanned
 784          */
 785         ec_ecdt = kmalloc(sizeof(struct acpi_ec), GFP_KERNEL);
 786         if (!ec_ecdt)
 787                 return -ENOMEM;
 788         memset(ec_ecdt, 0, sizeof(struct acpi_ec));
 789
 790         ec_ecdt->command_addr = ecdt_ptr->ec_control;
 791         ec_ecdt->status_addr = ecdt_ptr->ec_control;
 792         ec_ecdt->data_addr = ecdt_ptr->ec_data;
 793         ec_ecdt->gpe_bit = ecdt_ptr->gpe_bit;
 794         ec_ecdt->lock = SPIN_LOCK_UNLOCKED;
 795         /* use the GL just to be safe */
 796         ec_ecdt->global_lock = TRUE;
 797         ec_ecdt->uid = ecdt_ptr->uid;
 798
 799         status = acpi_get_handle(NULL, ecdt_ptr->ec_id, &ec_ecdt->handle);
 800         if (ACPI_FAILURE(status)) {
 801                 goto error;
 802         }
 803
 804         /*
 805          * Install GPE handler
 806          */
 807         status = acpi_install_gpe_handler(NULL, ec_ecdt->gpe_bit,
 808                 ACPI_GPE_EDGE_TRIGGERED, &acpi_ec_gpe_handler,
 809                 ec_ecdt);
 810         if (ACPI_FAILURE(status)) {
 811                 goto error;
 812         }
 813
 814         status = acpi_install_address_space_handler (ACPI_ROOT_OBJECT,
 815                         ACPI_ADR_SPACE_EC, &acpi_ec_space_handler,
 816                         &acpi_ec_space_setup, ec_ecdt);
 817         if (ACPI_FAILURE(status)) {
 818                 acpi_remove_gpe_handler(NULL, ec_ecdt->gpe_bit,
 819                         &acpi_ec_gpe_handler);
 820                 goto error;
 821         }
 822
 823         return 0;
 824
 825 error:
 826         printk(KERN_ERR PREFIX "Could not use ECDT\n");
 827         kfree(ec_ecdt);
 828         ec_ecdt = NULL;
 829
 830         return -ENODEV;
 831 }
 832
 833
 834 int __init
 835 acpi_ec_init (void)
 836 {
 837         int                     result = 0;
 838
 839         ACPI_FUNCTION_TRACE("acpi_ec_init");
 840
 841         acpi_ec_dir = proc_mkdir(ACPI_EC_CLASS, acpi_root_dir);
 842         if (!acpi_ec_dir)
 843                 return_VALUE(-ENODEV);
 844
 845         result = acpi_bus_register_driver(&acpi_ec_driver);
 846         if (result < 0) {
 847                 remove_proc_entry(ACPI_EC_CLASS, acpi_root_dir);
 848                 return_VALUE(-ENODEV);
 849         }
 850
 851         return_VALUE(0);
 852 }
 853
 854 /* EC can't be unloaded atm, so don't compile these */
 855 #if 0
 856 void __exit
 857 acpi_ec_exit (void)
 858 {
 859         ACPI_FUNCTION_TRACE("acpi_ec_exit");
 860
 861         acpi_bus_unregister_driver(&acpi_ec_driver);
 862
 863         remove_proc_entry(ACPI_EC_CLASS, acpi_root_dir);
 864
 865         return_VOID;
 866 }
 867 #endif /* 0 */
 868