drivers/acpi/ec.c

   1 /*
   2  *  acpi_ec.c - ACPI Embedded Controller Driver ($Revision: 38 $)
   3  *
   4  *  Copyright (C) 2004 Luming Yu <luming.yu@intel.com>
   5  *  Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
   6  *  Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
   7  *
   8  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   9  *
  10  *  This program is free software; you can redistribute it and/or modify
  11  *  it under the terms of the GNU General Public License as published by
  12  *  the Free Software Foundation; either version 2 of the License, or (at
  13  *  your option) any later version.
  14  *
  15  *  This program is distributed in the hope that it will be useful, but
  16  *  WITHOUT ANY WARRANTY; without even the implied warranty of
  17  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  18  *  General Public License for more details.
  19  *
  20  *  You should have received a copy of the GNU General Public License along
  21  *  with this program; if not, write to the Free Software Foundation, Inc.,
  22  *  59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
  23  *
  24  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  25  */
  26
  27 #include <linux/kernel.h>
  28 #include <linux/module.h>
  29 #include <linux/init.h>
  30 #include <linux/types.h>
  31 #include <linux/delay.h>
  32 #include <linux/proc_fs.h>
  33 #include <linux/seq_file.h>
  34 #include <asm/io.h>
  35 #include <acpi/acpi_bus.h>
  36 #include <acpi/acpi_drivers.h>
  37 #include <acpi/actypes.h>
  38
  39 #define _COMPONENT              ACPI_EC_COMPONENT
  40 ACPI_MODULE_NAME                ("acpi_ec")
  41
  42 #define ACPI_EC_COMPONENT               0x00100000
  43 #define ACPI_EC_CLASS                   "embedded_controller"
  44 #define ACPI_EC_HID                     "PNP0C09"
  45 #define ACPI_EC_DRIVER_NAME             "ACPI Embedded Controller Driver"
  46 #define ACPI_EC_DEVICE_NAME             "Embedded Controller"
  47 #define ACPI_EC_FILE_INFO               "info"
  48
  49
  50 #define ACPI_EC_FLAG_OBF        0x01    /* Output buffer full */
  51 #define ACPI_EC_FLAG_IBF        0x02    /* Input buffer full */
  52 #define ACPI_EC_FLAG_SCI        0x20    /* EC-SCI occurred */
  53
  54 #define ACPI_EC_EVENT_OBF       0x01    /* Output buffer full */
  55 #define ACPI_EC_EVENT_IBE       0x02    /* Input buffer empty */
  56
  57 #define ACPI_EC_UDELAY          100     /* Poll @ 100us increments */
  58 #define ACPI_EC_UDELAY_COUNT    1000    /* Wait 10ms max. during EC ops */
  59 #define ACPI_EC_UDELAY_GLK      1000    /* Wait 1ms max. to get global lock */
  60
  61 #define ACPI_EC_COMMAND_READ    0x80
  62 #define ACPI_EC_COMMAND_WRITE   0x81
  63 #define ACPI_EC_COMMAND_QUERY   0x84
  64
  65 static int acpi_ec_add (struct acpi_device *device);
  66 static int acpi_ec_remove (struct acpi_device *device, int type);
  67 static int acpi_ec_start (struct acpi_device *device);
  68 static int acpi_ec_stop (struct acpi_device *device, int type);
  69
  70 static struct acpi_driver acpi_ec_driver = {
  71         .name =         ACPI_EC_DRIVER_NAME,
  72         .class =        ACPI_EC_CLASS,
  73         .ids =          ACPI_EC_HID,
  74         .ops =          {
  75                                 .add =          acpi_ec_add,
  76                                 .remove =       acpi_ec_remove,
  77                                 .start =        acpi_ec_start,
  78                                 .stop =         acpi_ec_stop,
  79                         },
  80 };
  81
  82 struct acpi_ec {
  83         acpi_handle                     handle;
  84         unsigned long                   uid;
  85         unsigned long                   gpe_bit;
  86         struct acpi_generic_address     status_addr;
  87         struct acpi_generic_address     command_addr;
  88         struct acpi_generic_address     data_addr;
  89         unsigned long                   global_lock;
  90         spinlock_t                      lock;
  91 };
  92
  93 /* If we find an EC via the ECDT, we need to keep a ptr to its context */
  94 static struct acpi_ec   *ec_ecdt;
  95
  96 /* External interfaces use first EC only, so remember */
  97 static struct acpi_device *first_ec;
  98
  99 /* --------------------------------------------------------------------------
 100                              Transaction Management
 101    -------------------------------------------------------------------------- */
 102
 103 static int
 104 acpi_ec_wait (
 105         struct acpi_ec          *ec,
 106         u8                      event)
 107 {
 108         u32                     acpi_ec_status = 0;
 109         u32                     i = ACPI_EC_UDELAY_COUNT;
 110
 111         if (!ec)
 112                 return -EINVAL;
 113
 114         /* Poll the EC status register waiting for the event to occur. */
 115         switch (event) {
 116         case ACPI_EC_EVENT_OBF:
 117                 do {
 118                         acpi_hw_low_level_read(8, &acpi_ec_status, &ec->status_addr);
 119                         if (acpi_ec_status & ACPI_EC_FLAG_OBF)
 120                                 return 0;
 121                         udelay(ACPI_EC_UDELAY);
 122                 } while (--i>0);
 123                 break;
 124         case ACPI_EC_EVENT_IBE:
 125                 do {
 126                         acpi_hw_low_level_read(8, &acpi_ec_status, &ec->status_addr);
 127                         if (!(acpi_ec_status & ACPI_EC_FLAG_IBF))
 128                                 return 0;
 129                         udelay(ACPI_EC_UDELAY);
 130                 } while (--i>0);
 131                 break;
 132         default:
 133                 return -EINVAL;
 134         }
 135
 136         return -ETIME;
 137 }
 138
 139
 140 static int
 141 acpi_ec_read (
 142         struct acpi_ec          *ec,
 143         u8                      address,
 144         u32                     *data)
 145 {
 146         acpi_status             status = AE_OK;
 147         int                     result = 0;
 148         unsigned long           flags = 0;
 149         u32                     glk = 0;
 150
 151         ACPI_FUNCTION_TRACE("acpi_ec_read");
 152
 153         if (!ec || !data)
 154                 return_VALUE(-EINVAL);
 155
 156         *data = 0;
 157
 158         if (ec->global_lock) {
 159                 status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk);
 160                 if (ACPI_FAILURE(status))
 161                         return_VALUE(-ENODEV);
 162         }
 163
 164         spin_lock_irqsave(&ec->lock, flags);
 165
 166         acpi_hw_low_level_write(8, ACPI_EC_COMMAND_READ, &ec->command_addr);
 167         result = acpi_ec_wait(ec, ACPI_EC_EVENT_IBE);
 168         if (result)
 169                 goto end;
 170
 171         acpi_hw_low_level_write(8, address, &ec->data_addr);
 172         result = acpi_ec_wait(ec, ACPI_EC_EVENT_OBF);
 173         if (result)
 174                 goto end;
 175
 176
 177         acpi_hw_low_level_read(8, data, &ec->data_addr);
 178
 179         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Read [%02x] from address [%02x]\n",
 180                 *data, address));
 181
 182 end:
 183         spin_unlock_irqrestore(&ec->lock, flags);
 184
 185         if (ec->global_lock)
 186                 acpi_release_global_lock(glk);
 187
 188         return_VALUE(result);
 189 }
 190
 191
 192 static int
 193 acpi_ec_write (
 194         struct acpi_ec          *ec,
 195         u8                      address,
 196         u8                      data)
 197 {
 198         int                     result = 0;
 199         acpi_status             status = AE_OK;
 200         unsigned long           flags = 0;
 201         u32                     glk = 0;
 202
 203         ACPI_FUNCTION_TRACE("acpi_ec_write");
 204
 205         if (!ec)
 206                 return_VALUE(-EINVAL);
 207
 208         if (ec->global_lock) {
 209                 status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk);
 210                 if (ACPI_FAILURE(status))
 211                         return_VALUE(-ENODEV);
 212         }
 213
 214         spin_lock_irqsave(&ec->lock, flags);
 215
 216         acpi_hw_low_level_write(8, ACPI_EC_COMMAND_WRITE, &ec->command_addr);
 217         result = acpi_ec_wait(ec, ACPI_EC_EVENT_IBE);
 218         if (result)
 219                 goto end;
 220
 221         acpi_hw_low_level_write(8, address, &ec->data_addr);
 222         result = acpi_ec_wait(ec, ACPI_EC_EVENT_IBE);
 223         if (result)
 224                 goto end;
 225
 226         acpi_hw_low_level_write(8, data, &ec->data_addr);
 227         result = acpi_ec_wait(ec, ACPI_EC_EVENT_IBE);
 228         if (result)
 229                 goto end;
 230
 231         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Wrote [%02x] to address [%02x]\n",
 232                 data, address));
 233
 234 end:
 235         spin_unlock_irqrestore(&ec->lock, flags);
 236
 237         if (ec->global_lock)
 238                 acpi_release_global_lock(glk);
 239
 240         return_VALUE(result);
 241 }
 242
 243 /*
 244  * Externally callable EC access functions. For now, assume 1 EC only
 245  */
 246 int
 247 ec_read(u8 addr, u8 *val)
 248 {
 249         struct acpi_ec *ec;
 250         int err;
 251         u32 temp_data;
 252
 253         if (!first_ec)
 254                 return -ENODEV;
 255
 256         ec = acpi_driver_data(first_ec);
 257
 258         err = acpi_ec_read(ec, addr, &temp_data);
 259
 260         if (!err) {
 261                 *val = temp_data;
 262                 return 0;
 263         }
 264         else
 265                 return err;
 266 }
 267 EXPORT_SYMBOL(ec_read);
 268
 269 int
 270 ec_write(u8 addr, u8 val)
 271 {
 272         struct acpi_ec *ec;
 273         int err;
 274
 275         if (!first_ec)
 276                 return -ENODEV;
 277
 278         ec = acpi_driver_data(first_ec);
 279
 280         err = acpi_ec_write(ec, addr, val);
 281
 282         return err;
 283 }
 284 EXPORT_SYMBOL(ec_write);
 285
 286
 287 static int
 288 acpi_ec_query (
 289         struct acpi_ec          *ec,
 290         u32                     *data)
 291 {
 292         int                     result = 0;
 293         acpi_status             status = AE_OK;
 294         unsigned long           flags = 0;
 295         u32                     glk = 0;
 296
 297         ACPI_FUNCTION_TRACE("acpi_ec_query");
 298
 299         if (!ec || !data)
 300                 return_VALUE(-EINVAL);
 301
 302         *data = 0;
 303
 304         if (ec->global_lock) {
 305                 status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk);
 306                 if (ACPI_FAILURE(status))
 307                         return_VALUE(-ENODEV);
 308         }
 309
 310         /*
 311          * Query the EC to find out which _Qxx method we need to evaluate.
 312          * Note that successful completion of the query causes the ACPI_EC_SCI
 313          * bit to be cleared (and thus clearing the interrupt source).
 314          */
 315         spin_lock_irqsave(&ec->lock, flags);
 316
 317         acpi_hw_low_level_write(8, ACPI_EC_COMMAND_QUERY, &ec->command_addr);
 318         result = acpi_ec_wait(ec, ACPI_EC_EVENT_OBF);
 319         if (result)
 320                 goto end;
 321
 322         acpi_hw_low_level_read(8, data, &ec->data_addr);
 323         if (!*data)
 324                 result = -ENODATA;
 325
 326 end:
 327         spin_unlock_irqrestore(&ec->lock, flags);
 328
 329         if (ec->global_lock)
 330                 acpi_release_global_lock(glk);
 331
 332         return_VALUE(result);
 333 }
 334
 335
 336 /* --------------------------------------------------------------------------
 337                                 Event Management
 338    -------------------------------------------------------------------------- */
 339
 340 struct acpi_ec_query_data {
 341         acpi_handle             handle;
 342         u8                      data;
 343 };
 344
 345 static void
 346 acpi_ec_gpe_query (
 347         void                    *ec_cxt)
 348 {
 349         struct acpi_ec          *ec = (struct acpi_ec *) ec_cxt;
 350         u32                     value = 0;
 351         unsigned long           flags = 0;
 352         static char             object_name[5] = {'_','Q','0','0','\0'};
 353         const char              hex[] = {'0','1','2','3','4','5','6','7',
 354                                          '8','9','A','B','C','D','E','F'};
 355
 356         ACPI_FUNCTION_TRACE("acpi_ec_gpe_query");
 357
 358         if (!ec_cxt)
 359                 goto end;
 360
 361         spin_lock_irqsave(&ec->lock, flags);
 362         acpi_hw_low_level_read(8, &value, &ec->command_addr);
 363         spin_unlock_irqrestore(&ec->lock, flags);
 364
 365         /* TBD: Implement asynch events!
 366          * NOTE: All we care about are EC-SCI's.  Other EC events are
 367          * handled via polling (yuck!).  This is because some systems
 368          * treat EC-SCIs as level (versus EDGE!) triggered, preventing
 369          *  a purely interrupt-driven approach (grumble, grumble).
 370          */
 371         if (!(value & ACPI_EC_FLAG_SCI))
 372                 goto end;
 373
 374         if (acpi_ec_query(ec, &value))
 375                 goto end;
 376
 377         object_name[2] = hex[((value >> 4) & 0x0F)];
 378         object_name[3] = hex[(value & 0x0F)];
 379
 380         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Evaluating %s\n", object_name));
 381
 382         acpi_evaluate_object(ec->handle, object_name, NULL, NULL);
 383
 384 end:
 385         acpi_enable_gpe(NULL, ec->gpe_bit, ACPI_NOT_ISR);
 386 }
 387
 388 static u32
 389 acpi_ec_gpe_handler (
 390         void                    *data)
 391 {
 392         acpi_status             status = AE_OK;
 393         struct acpi_ec          *ec = (struct acpi_ec *) data;
 394
 395         if (!ec)
 396                 return ACPI_INTERRUPT_NOT_HANDLED;
 397
 398         acpi_disable_gpe(NULL, ec->gpe_bit, ACPI_ISR);
 399
 400         status = acpi_os_queue_for_execution(OSD_PRIORITY_GPE,
 401                 acpi_ec_gpe_query, ec);
 402
 403         if (status == AE_OK)
 404                 return ACPI_INTERRUPT_HANDLED;
 405         else
 406                 return ACPI_INTERRUPT_NOT_HANDLED;
 407 }
 408
 409 /* --------------------------------------------------------------------------
 410                              Address Space Management
 411    -------------------------------------------------------------------------- */
 412
 413 static acpi_status
 414 acpi_ec_space_setup (
 415         acpi_handle             region_handle,
 416         u32                     function,
 417         void                    *handler_context,
 418         void                    **return_context)
 419 {
 420         /*
 421          * The EC object is in the handler context and is needed
 422          * when calling the acpi_ec_space_handler.
 423          */
 424         if(function == ACPI_REGION_DEACTIVATE)
 425                 *return_context = NULL;
 426         else
 427                 *return_context = handler_context;
 428
 429         return AE_OK;
 430 }
 431
 432
 433 static acpi_status
 434 acpi_ec_space_handler (
 435         u32                     function,
 436         acpi_physical_address   address,
 437         u32                     bit_width,
 438         acpi_integer            *value,
 439         void                    *handler_context,
 440         void                    *region_context)
 441 {
 442         int                     result = 0;
 443         struct acpi_ec          *ec = NULL;
 444         u32                     temp = 0;
 445         acpi_integer            f_v = 0;
 446         int                     i = 0;
 447
 448         ACPI_FUNCTION_TRACE("acpi_ec_space_handler");
 449
 450         if ((address > 0xFF) || !value || !handler_context)
 451                 return_VALUE(AE_BAD_PARAMETER);
 452
 453         if(bit_width != 8) {
 454                 printk(KERN_WARNING PREFIX "acpi_ec_space_handler: bit_width should be 8\n");
 455                 if (acpi_strict)
 456                         return_VALUE(AE_BAD_PARAMETER);
 457         }
 458
 459         ec = (struct acpi_ec *) handler_context;
 460
 461 next_byte:
 462         switch (function) {
 463         case ACPI_READ:
 464                 result = acpi_ec_read(ec, (u8) address, &temp);
 465                 *value = (acpi_integer) temp;
 466                 break;
 467         case ACPI_WRITE:
 468                 result = acpi_ec_write(ec, (u8) address, (u8) *value);
 469                 break;
 470         default:
 471                 result = -EINVAL;
 472                 goto out;
 473                 break;
 474         }
 475
 476         bit_width -= 8;
 477         if(bit_width){
 478
 479                 if(function == ACPI_READ)
 480                         f_v |= (acpi_integer) (*value) << 8*i;
 481                 if(function == ACPI_WRITE)
 482                         (*value) >>=8;
 483                 i++;
 484                 goto next_byte;
 485         }
 486
 487
 488         if(function == ACPI_READ){
 489                 f_v |= (acpi_integer) (*value) << 8*i;
 490                 *value = f_v;
 491         }
 492
 493
 494 out:
 495         switch (result) {
 496         case -EINVAL:
 497                 return_VALUE(AE_BAD_PARAMETER);
 498                 break;
 499         case -ENODEV:
 500                 return_VALUE(AE_NOT_FOUND);
 501                 break;
 502         case -ETIME:
 503                 return_VALUE(AE_TIME);
 504                 break;
 505         default:
 506                 return_VALUE(AE_OK);
 507         }
 508
 509
 510 }
 511
 512
 513 /* --------------------------------------------------------------------------
 514                               FS Interface (/proc)
 515    -------------------------------------------------------------------------- */
 516
 517 static struct proc_dir_entry    *acpi_ec_dir;
 518
 519
 520 static int
 521 acpi_ec_read_info (struct seq_file *seq, void *offset)
 522 {
 523         struct acpi_ec          *ec = (struct acpi_ec *) seq->private;
 524
 525         ACPI_FUNCTION_TRACE("acpi_ec_read_info");
 526
 527         if (!ec)
 528                 goto end;
 529
 530         seq_printf(seq, "gpe bit:                 0x%02x\n",
 531                 (u32) ec->gpe_bit);
 532         seq_printf(seq, "ports:                   0x%02x, 0x%02x\n",
 533                 (u32) ec->status_addr.address, (u32) ec->data_addr.address);
 534         seq_printf(seq, "use global lock:         %s\n",
 535                 ec->global_lock?"yes":"no");
 536
 537 end:
 538         return_VALUE(0);
 539 }
 540
 541 static int acpi_ec_info_open_fs(struct inode *inode, struct file *file)
 542 {
 543         return single_open(file, acpi_ec_read_info, PDE(inode)->data);
 544 }
 545
 546 static struct file_operations acpi_ec_info_ops = {
 547         .open           = acpi_ec_info_open_fs,
 548         .read           = seq_read,
 549         .llseek         = seq_lseek,
 550         .release        = single_release,
 551         .owner = THIS_MODULE,
 552 };
 553
 554 static int
 555 acpi_ec_add_fs (
 556         struct acpi_device      *device)
 557 {
 558         struct proc_dir_entry   *entry = NULL;
 559
 560         ACPI_FUNCTION_TRACE("acpi_ec_add_fs");
 561
 562         if (!acpi_device_dir(device)) {
 563                 acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device),
 564                         acpi_ec_dir);
 565                 if (!acpi_device_dir(device))
 566                         return_VALUE(-ENODEV);
 567         }
 568
 569         entry = create_proc_entry(ACPI_EC_FILE_INFO, S_IRUGO,
 570                 acpi_device_dir(device));
 571         if (!entry)
 572                 ACPI_DEBUG_PRINT((ACPI_DB_WARN,
 573                         "Unable to create '%s' fs entry\n",
 574                         ACPI_EC_FILE_INFO));
 575         else {
 576                 entry->proc_fops = &acpi_ec_info_ops;
 577                 entry->data = acpi_driver_data(device);
 578                 entry->owner = THIS_MODULE;
 579         }
 580
 581         return_VALUE(0);
 582 }
 583
 584
 585 static int
 586 acpi_ec_remove_fs (
 587         struct acpi_device      *device)
 588 {
 589         ACPI_FUNCTION_TRACE("acpi_ec_remove_fs");
 590
 591         if (acpi_device_dir(device)) {
 592                 remove_proc_entry(ACPI_EC_FILE_INFO, acpi_device_dir(device));
 593                 remove_proc_entry(acpi_device_bid(device), acpi_ec_dir);
 594                 acpi_device_dir(device) = NULL;
 595         }
 596
 597         return_VALUE(0);
 598 }
 599
 600
 601 /* --------------------------------------------------------------------------
 602                                Driver Interface
 603    -------------------------------------------------------------------------- */
 604
 605 static int
 606 acpi_ec_add (
 607         struct acpi_device      *device)
 608 {
 609         int                     result = 0;
 610         acpi_status             status = AE_OK;
 611         struct acpi_ec          *ec = NULL;
 612         unsigned long           uid;
 613
 614         ACPI_FUNCTION_TRACE("acpi_ec_add");
 615
 616         if (!device)
 617                 return_VALUE(-EINVAL);
 618
 619         ec = kmalloc(sizeof(struct acpi_ec), GFP_KERNEL);
 620         if (!ec)
 621                 return_VALUE(-ENOMEM);
 622         memset(ec, 0, sizeof(struct acpi_ec));
 623
 624         ec->handle = device->handle;
 625         ec->uid = -1;
 626         spin_lock_init(&ec->lock);
 627         strcpy(acpi_device_name(device), ACPI_EC_DEVICE_NAME);
 628         strcpy(acpi_device_class(device), ACPI_EC_CLASS);
 629         acpi_driver_data(device) = ec;
 630
 631         /* Use the global lock for all EC transactions? */
 632         acpi_evaluate_integer(ec->handle, "_GLK", NULL, &ec->global_lock);
 633
 634         /* If our UID matches the UID for the ECDT-enumerated EC,
 635            we now have the *real* EC info, so kill the makeshift one.*/
 636         acpi_evaluate_integer(ec->handle, "_UID", NULL, &uid);
 637         if (ec_ecdt && ec_ecdt->uid == uid) {
 638                 acpi_remove_address_space_handler(ACPI_ROOT_OBJECT,
 639                         ACPI_ADR_SPACE_EC, &acpi_ec_space_handler);
 640
 641                 acpi_remove_gpe_handler(NULL, ec_ecdt->gpe_bit, &acpi_ec_gpe_handler);
 642
 643                 kfree(ec_ecdt);
 644         }
 645
 646         /* Get GPE bit assignment (EC events). */
 647         /* TODO: Add support for _GPE returning a package */
 648         status = acpi_evaluate_integer(ec->handle, "_GPE", NULL, &ec->gpe_bit);
 649         if (ACPI_FAILURE(status)) {
 650                 ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
 651                         "Error obtaining GPE bit assignment\n"));
 652                 result = -ENODEV;
 653                 goto end;
 654         }
 655
 656         result = acpi_ec_add_fs(device);
 657         if (result)
 658                 goto end;
 659
 660         printk(KERN_INFO PREFIX "%s [%s] (gpe %d)\n",
 661                 acpi_device_name(device), acpi_device_bid(device),
 662                 (u32) ec->gpe_bit);
 663
 664         if (!first_ec)
 665                 first_ec = device;
 666
 667 end:
 668         if (result)
 669                 kfree(ec);
 670
 671         return_VALUE(result);
 672 }
 673
 674
 675 static int
 676 acpi_ec_remove (
 677         struct acpi_device      *device,
 678         int                     type)
 679 {
 680         struct acpi_ec          *ec = NULL;
 681
 682         ACPI_FUNCTION_TRACE("acpi_ec_remove");
 683
 684         if (!device)
 685                 return_VALUE(-EINVAL);
 686
 687         ec = acpi_driver_data(device);
 688
 689         acpi_ec_remove_fs(device);
 690
 691         kfree(ec);
 692
 693         return_VALUE(0);
 694 }
 695
 696
 697 static acpi_status
 698 acpi_ec_io_ports (
 699         struct acpi_resource    *resource,
 700         void                    *context)
 701 {
 702         struct acpi_ec          *ec = (struct acpi_ec *) context;
 703         struct acpi_generic_address *addr;
 704
 705         if (resource->id != ACPI_RSTYPE_IO) {
 706                 return AE_OK;
 707         }
 708
 709         /*
 710          * The first address region returned is the data port, and
 711          * the second address region returned is the status/command
 712          * port.
 713          */
 714         if (ec->data_addr.register_bit_width == 0) {
 715                 addr = &ec->data_addr;
 716         } else if (ec->command_addr.register_bit_width == 0) {
 717                 addr = &ec->command_addr;
 718         } else {
 719                 return AE_CTRL_TERMINATE;
 720         }
 721
 722         addr->address_space_id = ACPI_ADR_SPACE_SYSTEM_IO;
 723         addr->register_bit_width = 8;
 724         addr->register_bit_offset = 0;
 725         addr->address = resource->data.io.min_base_address;
 726
 727         return AE_OK;
 728 }
 729
 730
 731 static int
 732 acpi_ec_start (
 733         struct acpi_device      *device)
 734 {
 735         acpi_status             status = AE_OK;
 736         struct acpi_ec          *ec = NULL;
 737
 738         ACPI_FUNCTION_TRACE("acpi_ec_start");
 739
 740         if (!device)
 741                 return_VALUE(-EINVAL);
 742
 743         ec = acpi_driver_data(device);
 744
 745         if (!ec)
 746                 return_VALUE(-EINVAL);
 747
 748         /*
 749          * Get I/O port addresses. Convert to GAS format.
 750          */
 751         status = acpi_walk_resources(ec->handle, METHOD_NAME__CRS,
 752                 acpi_ec_io_ports, ec);
 753         if (ACPI_FAILURE(status) || ec->command_addr.register_bit_width == 0) {
 754                 ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Error getting I/O port addresses"));
 755                 return_VALUE(-ENODEV);
 756         }
 757
 758         ec->status_addr = ec->command_addr;
 759
 760         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "gpe=0x%02x, ports=0x%2x,0x%2x\n",
 761                 (u32) ec->gpe_bit, (u32) ec->command_addr.address,
 762                 (u32) ec->data_addr.address));
 763
 764         /*
 765          * Install GPE handler
 766          */
 767         status = acpi_install_gpe_handler(NULL, ec->gpe_bit,
 768                 ACPI_GPE_EDGE_TRIGGERED, &acpi_ec_gpe_handler, ec);
 769         if (ACPI_FAILURE(status)) {
 770                 return_VALUE(-ENODEV);
 771         }
 772         acpi_set_gpe_type (NULL, ec->gpe_bit, ACPI_GPE_TYPE_RUNTIME);
 773         acpi_enable_gpe (NULL, ec->gpe_bit, ACPI_NOT_ISR);
 774
 775         status = acpi_install_address_space_handler (ec->handle,
 776                         ACPI_ADR_SPACE_EC, &acpi_ec_space_handler,
 777                         &acpi_ec_space_setup, ec);
 778         if (ACPI_FAILURE(status)) {
 779                 acpi_remove_gpe_handler(NULL, ec->gpe_bit, &acpi_ec_gpe_handler);
 780                 return_VALUE(-ENODEV);
 781         }
 782
 783         return_VALUE(AE_OK);
 784 }
 785
 786
 787 static int
 788 acpi_ec_stop (
 789         struct acpi_device      *device,
 790         int                     type)
 791 {
 792         acpi_status             status = AE_OK;
 793         struct acpi_ec          *ec = NULL;
 794
 795         ACPI_FUNCTION_TRACE("acpi_ec_stop");
 796
 797         if (!device)
 798                 return_VALUE(-EINVAL);
 799
 800         ec = acpi_driver_data(device);
 801
 802         status = acpi_remove_address_space_handler(ec->handle,
 803                 ACPI_ADR_SPACE_EC, &acpi_ec_space_handler);
 804         if (ACPI_FAILURE(status))
 805                 return_VALUE(-ENODEV);
 806
 807         status = acpi_remove_gpe_handler(NULL, ec->gpe_bit, &acpi_ec_gpe_handler);
 808         if (ACPI_FAILURE(status))
 809                 return_VALUE(-ENODEV);
 810
 811         return_VALUE(0);
 812 }
 813
 814 static acpi_status __init
 815 acpi_fake_ecdt_callback (
 816         acpi_handle     handle,
 817         u32             Level,
 818         void            *context,
 819         void            **retval)
 820 {
 821         acpi_status     status;
 822
 823         status = acpi_walk_resources(handle, METHOD_NAME__CRS,
 824                 acpi_ec_io_ports, ec_ecdt);
 825         if (ACPI_FAILURE(status))
 826                 return status;
 827         ec_ecdt->status_addr = ec_ecdt->command_addr;
 828
 829         ec_ecdt->uid = -1;
 830         acpi_evaluate_integer(handle, "_UID", NULL, &ec_ecdt->uid);
 831
 832         status = acpi_evaluate_integer(handle, "_GPE", NULL, &ec_ecdt->gpe_bit);
 833         if (ACPI_FAILURE(status))
 834                 return status;
 835         spin_lock_init(&ec_ecdt->lock);
 836         ec_ecdt->global_lock = TRUE;
 837         ec_ecdt->handle = handle;
 838
 839         printk(KERN_INFO PREFIX  "GPE=0x%02x, ports=0x%2x, 0x%2x\n",
 840                 (u32) ec_ecdt->gpe_bit, (u32) ec_ecdt->command_addr.address,
 841                 (u32) ec_ecdt->data_addr.address);
 842
 843         return AE_CTRL_TERMINATE;
 844 }
 845
 846 /*
 847  * Some BIOS (such as some from Gateway laptops) access EC region very early
 848  * such as in BAT0._INI or EC._INI before an EC device is found and
 849  * do not provide an ECDT. According to ACPI spec, ECDT isn't mandatorily
 850  * required, but if EC regison is accessed early, it is required.
 851  * The routine tries to workaround the BIOS bug by pre-scan EC device
 852  * It assumes that _CRS, _HID, _GPE, _UID methods of EC don't touch any
 853  * op region (since _REG isn't invoked yet). The assumption is true for
 854  * all systems found.
 855  */
 856 static int __init
 857 acpi_ec_fake_ecdt(void)
 858 {
 859         acpi_status     status;
 860         int             ret = 0;
 861
 862         printk(KERN_INFO PREFIX "Try to make an fake ECDT\n");
 863
 864         ec_ecdt = kmalloc(sizeof(struct acpi_ec), GFP_KERNEL);
 865         if (!ec_ecdt) {
 866                 ret = -ENOMEM;
 867                 goto error;
 868         }
 869         memset(ec_ecdt, 0, sizeof(struct acpi_ec));
 870
 871         status = acpi_get_devices (ACPI_EC_HID,
 872                                 acpi_fake_ecdt_callback,
 873                                 NULL,
 874                                 NULL);
 875         if (ACPI_FAILURE(status)) {
 876                 kfree(ec_ecdt);
 877                 ec_ecdt = NULL;
 878                 ret = -ENODEV;
 879                 goto error;
 880         }
 881         return 0;
 882 error:
 883         printk(KERN_ERR PREFIX "Can't make an fake ECDT\n");
 884         return ret;
 885 }
 886
 887 static int __init
 888 acpi_ec_get_real_ecdt(void)
 889 {
 890         acpi_status             status;
 891         struct acpi_table_ecdt  *ecdt_ptr;
 892
 893         status = acpi_get_firmware_table("ECDT", 1, ACPI_LOGICAL_ADDRESSING,
 894                 (struct acpi_table_header **) &ecdt_ptr);
 895         if (ACPI_FAILURE(status))
 896                 return -ENODEV;
 897
 898         printk(KERN_INFO PREFIX "Found ECDT\n");
 899
 900         /*
 901          * Generate a temporary ec context to use until the namespace is scanned
 902          */
 903         ec_ecdt = kmalloc(sizeof(struct acpi_ec), GFP_KERNEL);
 904         if (!ec_ecdt)
 905                 return -ENOMEM;
 906         memset(ec_ecdt, 0, sizeof(struct acpi_ec));
 907
 908         ec_ecdt->command_addr = ecdt_ptr->ec_control;
 909         ec_ecdt->status_addr = ecdt_ptr->ec_control;
 910         ec_ecdt->data_addr = ecdt_ptr->ec_data;
 911         ec_ecdt->gpe_bit = ecdt_ptr->gpe_bit;
 912         spin_lock_init(&ec_ecdt->lock);
 913         /* use the GL just to be safe */
 914         ec_ecdt->global_lock = TRUE;
 915         ec_ecdt->uid = ecdt_ptr->uid;
 916
 917         status = acpi_get_handle(NULL, ecdt_ptr->ec_id, &ec_ecdt->handle);
 918         if (ACPI_FAILURE(status)) {
 919                 goto error;
 920         }
 921
 922         return 0;
 923 error:
 924         printk(KERN_ERR PREFIX "Could not use ECDT\n");
 925         kfree(ec_ecdt);
 926         ec_ecdt = NULL;
 927
 928         return -ENODEV;
 929 }
 930
 931 static int __initdata acpi_fake_ecdt_enabled;
 932 int __init
 933 acpi_ec_ecdt_probe (void)
 934 {
 935         acpi_status             status;
 936         int                     ret;
 937
 938         ret = acpi_ec_get_real_ecdt();
 939         /* Try to make a fake ECDT */
 940         if (ret && acpi_fake_ecdt_enabled) {
 941                 ret = acpi_ec_fake_ecdt();
 942         }
 943
 944         if (ret)
 945                 return 0;
 946
 947         /*
 948          * Install GPE handler
 949          */
 950         status = acpi_install_gpe_handler(NULL, ec_ecdt->gpe_bit,
 951                 ACPI_GPE_EDGE_TRIGGERED, &acpi_ec_gpe_handler,
 952                 ec_ecdt);
 953         if (ACPI_FAILURE(status)) {
 954                 goto error;
 955         }
 956         acpi_set_gpe_type (NULL, ec_ecdt->gpe_bit, ACPI_GPE_TYPE_RUNTIME);
 957         acpi_enable_gpe (NULL, ec_ecdt->gpe_bit, ACPI_NOT_ISR);
 958
 959         status = acpi_install_address_space_handler (ACPI_ROOT_OBJECT,
 960                         ACPI_ADR_SPACE_EC, &acpi_ec_space_handler,
 961                         &acpi_ec_space_setup, ec_ecdt);
 962         if (ACPI_FAILURE(status)) {
 963                 acpi_remove_gpe_handler(NULL, ec_ecdt->gpe_bit,
 964                         &acpi_ec_gpe_handler);
 965                 goto error;
 966         }
 967
 968         return 0;
 969
 970 error:
 971         printk(KERN_ERR PREFIX "Could not use ECDT\n");
 972         kfree(ec_ecdt);
 973         ec_ecdt = NULL;
 974
 975         return -ENODEV;
 976 }
 977
 978
 979 static int __init acpi_ec_init (void)
 980 {
 981         int                     result = 0;
 982
 983         ACPI_FUNCTION_TRACE("acpi_ec_init");
 984
 985         if (acpi_disabled)
 986                 return_VALUE(0);
 987
 988         acpi_ec_dir = proc_mkdir(ACPI_EC_CLASS, acpi_root_dir);
 989         if (!acpi_ec_dir)
 990                 return_VALUE(-ENODEV);
 991
 992         /* Now register the driver for the EC */
 993         result = acpi_bus_register_driver(&acpi_ec_driver);
 994         if (result < 0) {
 995                 remove_proc_entry(ACPI_EC_CLASS, acpi_root_dir);
 996                 return_VALUE(-ENODEV);
 997         }
 998
 999         return_VALUE(result);
1000 }
1001
1002 subsys_initcall(acpi_ec_init);
1003
1004 /* EC driver currently not unloadable */
1005 #if 0
1006 static void __exit
1007 acpi_ec_exit (void)
1008 {
1009         ACPI_FUNCTION_TRACE("acpi_ec_exit");
1010
1011         acpi_bus_unregister_driver(&acpi_ec_driver);
1012
1013         remove_proc_entry(ACPI_EC_CLASS, acpi_root_dir);
1014
1015         return_VOID;
1016 }
1017 #endif /* 0 */
1018
1019 static int __init acpi_fake_ecdt_setup(char *str)
1020 {
1021         acpi_fake_ecdt_enabled = 1;
1022         return 0;
1023 }
1024 __setup("acpi_fake_ecdt", acpi_fake_ecdt_setup);