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 <linux/interrupt.h>
  35 #include <asm/io.h>
  36 #include <acpi/acpi_bus.h>
  37 #include <acpi/acpi_drivers.h>
  38 #include <acpi/actypes.h>
  39
  40 #define _COMPONENT              ACPI_EC_COMPONENT
  41 ACPI_MODULE_NAME                ("acpi_ec")
  42
  43 #define ACPI_EC_COMPONENT               0x00100000
  44 #define ACPI_EC_CLASS                   "embedded_controller"
  45 #define ACPI_EC_HID                     "PNP0C09"
  46 #define ACPI_EC_DRIVER_NAME             "ACPI Embedded Controller Driver"
  47 #define ACPI_EC_DEVICE_NAME             "Embedded Controller"
  48 #define ACPI_EC_FILE_INFO               "info"
  49
  50
  51 #define ACPI_EC_FLAG_OBF        0x01    /* Output buffer full */
  52 #define ACPI_EC_FLAG_IBF        0x02    /* Input buffer full */
  53 #define ACPI_EC_FLAG_BURST      0x10    /* burst mode */
  54 #define ACPI_EC_FLAG_SCI        0x20    /* EC-SCI occurred */
  55
  56 #define ACPI_EC_EVENT_OBF       0x01    /* Output buffer full */
  57 #define ACPI_EC_EVENT_IBE       0x02    /* Input buffer empty */
  58
  59 #define ACPI_EC_DELAY           50      /* Wait 50ms max. during EC ops */
  60 #define ACPI_EC_UDELAY_GLK      1000    /* Wait 1ms max. to get global lock */
  61
  62 #define ACPI_EC_COMMAND_READ    0x80
  63 #define ACPI_EC_COMMAND_WRITE   0x81
  64 #define ACPI_EC_BURST_ENABLE    0x82
  65 #define ACPI_EC_BURST_DISABLE   0x83
  66 #define ACPI_EC_COMMAND_QUERY   0x84
  67
  68 static int acpi_ec_add (struct acpi_device *device);
  69 static int acpi_ec_remove (struct acpi_device *device, int type);
  70 static int acpi_ec_start (struct acpi_device *device);
  71 static int acpi_ec_stop (struct acpi_device *device, int type);
  72
  73 static struct acpi_driver acpi_ec_driver = {
  74         .name =         ACPI_EC_DRIVER_NAME,
  75         .class =        ACPI_EC_CLASS,
  76         .ids =          ACPI_EC_HID,
  77         .ops =          {
  78                                 .add =          acpi_ec_add,
  79                                 .remove =       acpi_ec_remove,
  80                                 .start =        acpi_ec_start,
  81                                 .stop =         acpi_ec_stop,
  82                         },
  83 };
  84
  85 struct acpi_ec {
  86         acpi_handle                     handle;
  87         unsigned long                   uid;
  88         unsigned long                   gpe_bit;
  89         struct acpi_generic_address     status_addr;
  90         struct acpi_generic_address     command_addr;
  91         struct acpi_generic_address     data_addr;
  92         unsigned long                   global_lock;
  93         unsigned int                    expect_event;
  94         atomic_t                        leaving_burst; /* 0 : No, 1 : Yes, 2: abort*/
  95         atomic_t                        pending_gpe;
  96         struct semaphore                sem;
  97         wait_queue_head_t               wait;
  98 };
  99
 100 /* If we find an EC via the ECDT, we need to keep a ptr to its context */
 101 static struct acpi_ec   *ec_ecdt;
 102
 103 /* External interfaces use first EC only, so remember */
 104 static struct acpi_device *first_ec;
 105
 106 /* --------------------------------------------------------------------------
 107                              Transaction Management
 108    -------------------------------------------------------------------------- */
 109
 110 static inline u32 acpi_ec_read_status(struct acpi_ec *ec)
 111 {
 112         u32     status = 0;
 113
 114         acpi_hw_low_level_read(8, &status, &ec->status_addr);
 115         return status;
 116 }
 117
 118 static int acpi_ec_wait(struct acpi_ec *ec, unsigned int event)
 119 {
 120         int     result = 0;
 121
 122         ACPI_FUNCTION_TRACE("acpi_ec_wait");
 123
 124         ec->expect_event = event;
 125         smp_mb();
 126
 127         result = wait_event_interruptible_timeout(ec->wait,
 128                                         !ec->expect_event,
 129                                         msecs_to_jiffies(ACPI_EC_DELAY));
 130
 131         ec->expect_event = 0;
 132         smp_mb();
 133
 134         if (result < 0){
 135                 ACPI_DEBUG_PRINT((ACPI_DB_ERROR," result  = %d ", result));
 136                 return_VALUE(result);
 137         }
 138
 139         /*
 140          * Verify that the event in question has actually happened by
 141          * querying EC status. Do the check even if operation timed-out
 142          * to make sure that we did not miss interrupt.
 143          */
 144         switch (event) {
 145         case ACPI_EC_EVENT_OBF:
 146                 if (acpi_ec_read_status(ec) & ACPI_EC_FLAG_OBF)
 147                         return_VALUE(0);
 148                 break;
 149
 150         case ACPI_EC_EVENT_IBE:
 151                 if (~acpi_ec_read_status(ec) & ACPI_EC_FLAG_IBF)
 152                         return_VALUE(0);
 153                 break;
 154         }
 155
 156         return_VALUE(-ETIME);
 157 }
 158
 159
 160
 161 static int
 162 acpi_ec_enter_burst_mode (
 163         struct acpi_ec          *ec)
 164 {
 165         u32                     tmp = 0;
 166         int                     status = 0;
 167
 168         ACPI_FUNCTION_TRACE("acpi_ec_enter_burst_mode");
 169
 170         status = acpi_ec_read_status(ec);
 171         if (status != -EINVAL &&
 172                 !(status & ACPI_EC_FLAG_BURST)){
 173                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,"entering burst mode \n"));
 174                 acpi_hw_low_level_write(8, ACPI_EC_BURST_ENABLE, &ec->command_addr);
 175                 status = acpi_ec_wait(ec, ACPI_EC_EVENT_OBF);
 176                 if (status){
 177                         acpi_enable_gpe(NULL, ec->gpe_bit, ACPI_NOT_ISR);
 178                         ACPI_DEBUG_PRINT((ACPI_DB_ERROR," status = %d\n", status));
 179                         return_VALUE(-EINVAL);
 180                 }
 181                 acpi_hw_low_level_read(8, &tmp, &ec->data_addr);
 182                 acpi_enable_gpe(NULL, ec->gpe_bit, ACPI_NOT_ISR);
 183                 if(tmp != 0x90 ) {/* Burst ACK byte*/
 184                         ACPI_DEBUG_PRINT((ACPI_DB_ERROR,"Ack failed \n"));
 185                         return_VALUE(-EINVAL);
 186                 }
 187         } else
 188                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,"already be in burst mode \n"));
 189         atomic_set(&ec->leaving_burst , 0);
 190         return_VALUE(0);
 191 }
 192
 193 static int
 194 acpi_ec_leave_burst_mode (
 195         struct acpi_ec          *ec)
 196 {
 197         int                     status =0;
 198
 199         ACPI_FUNCTION_TRACE("acpi_ec_leave_burst_mode");
 200
 201         atomic_set(&ec->leaving_burst , 1);
 202         status = acpi_ec_read_status(ec);
 203         if (status != -EINVAL &&
 204                 (status & ACPI_EC_FLAG_BURST)){
 205                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,"leaving burst mode\n"));
 206                 acpi_hw_low_level_write(8, ACPI_EC_BURST_DISABLE, &ec->command_addr);
 207                 status = acpi_ec_wait(ec, ACPI_EC_FLAG_IBF);
 208                 if (status){
 209                         acpi_enable_gpe(NULL, ec->gpe_bit, ACPI_NOT_ISR);
 210                         ACPI_DEBUG_PRINT((ACPI_DB_ERROR,"------->wait fail\n"));
 211                         return_VALUE(-EINVAL);
 212                 }
 213                 acpi_enable_gpe(NULL, ec->gpe_bit, ACPI_NOT_ISR);
 214                 status = acpi_ec_read_status(ec);
 215                 if (status != -EINVAL &&
 216                         (status & ACPI_EC_FLAG_BURST)) {
 217                         ACPI_DEBUG_PRINT((ACPI_DB_ERROR,"------->status fail\n"));
 218                         return_VALUE(-EINVAL);
 219                 }
 220         }else
 221                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,"already be in Non-burst mode \n"));
 222         ACPI_DEBUG_PRINT((ACPI_DB_INFO,"leaving burst mode\n"));
 223
 224         return_VALUE(0);
 225 }
 226
 227 static int
 228 acpi_ec_read (
 229         struct acpi_ec          *ec,
 230         u8                      address,
 231         u32                     *data)
 232 {
 233         int                     status = 0;
 234         u32                     glk;
 235
 236         ACPI_FUNCTION_TRACE("acpi_ec_read");
 237
 238         if (!ec || !data)
 239                 return_VALUE(-EINVAL);
 240
 241 retry:
 242         *data = 0;
 243
 244         if (ec->global_lock) {
 245                 status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk);
 246                 if (ACPI_FAILURE(status))
 247                         return_VALUE(-ENODEV);
 248         }
 249
 250         WARN_ON(in_interrupt());
 251         down(&ec->sem);
 252
 253         if(acpi_ec_enter_burst_mode(ec))
 254                 goto end;
 255
 256         acpi_hw_low_level_write(8, ACPI_EC_COMMAND_READ, &ec->command_addr);
 257         status = acpi_ec_wait(ec, ACPI_EC_EVENT_IBE);
 258         acpi_enable_gpe(NULL, ec->gpe_bit, ACPI_NOT_ISR);
 259         if (status) {
 260                 goto end;
 261         }
 262
 263         acpi_hw_low_level_write(8, address, &ec->data_addr);
 264         status= acpi_ec_wait(ec, ACPI_EC_EVENT_OBF);
 265         if (status){
 266                 acpi_enable_gpe(NULL, ec->gpe_bit, ACPI_NOT_ISR);
 267                 goto end;
 268         }
 269
 270         acpi_hw_low_level_read(8, data, &ec->data_addr);
 271         acpi_enable_gpe(NULL, ec->gpe_bit, ACPI_NOT_ISR);
 272
 273         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Read [%02x] from address [%02x]\n",
 274                 *data, address));
 275
 276 end:
 277         acpi_ec_leave_burst_mode(ec);
 278         up(&ec->sem);
 279
 280         if (ec->global_lock)
 281                 acpi_release_global_lock(glk);
 282
 283         if(atomic_read(&ec->leaving_burst) == 2){
 284                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,"aborted, retry ...\n"));
 285                 while(!atomic_read(&ec->pending_gpe)){
 286                         msleep(1);
 287                 }
 288                 acpi_enable_gpe(NULL, ec->gpe_bit, ACPI_NOT_ISR);
 289                 goto retry;
 290         }
 291
 292         return_VALUE(status);
 293 }
 294
 295
 296 static int
 297 acpi_ec_write (
 298         struct acpi_ec          *ec,
 299         u8                      address,
 300         u8                      data)
 301 {
 302         int                     status = 0;
 303         u32                     glk;
 304         u32                     tmp;
 305
 306         ACPI_FUNCTION_TRACE("acpi_ec_write");
 307
 308         if (!ec)
 309                 return_VALUE(-EINVAL);
 310 retry:
 311         if (ec->global_lock) {
 312                 status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk);
 313                 if (ACPI_FAILURE(status))
 314                         return_VALUE(-ENODEV);
 315         }
 316
 317         WARN_ON(in_interrupt());
 318         down(&ec->sem);
 319
 320         if(acpi_ec_enter_burst_mode(ec))
 321                 goto end;
 322
 323         status = acpi_ec_read_status(ec);
 324         if (status != -EINVAL &&
 325                 !(status & ACPI_EC_FLAG_BURST)){
 326                 acpi_hw_low_level_write(8, ACPI_EC_BURST_ENABLE, &ec->command_addr);
 327                 status = acpi_ec_wait(ec, ACPI_EC_EVENT_OBF);
 328                 if (status)
 329                         goto end;
 330                 acpi_hw_low_level_read(8, &tmp, &ec->data_addr);
 331                 if(tmp != 0x90 ) /* Burst ACK byte*/
 332                         goto end;
 333         }
 334         /*Now we are in burst mode*/
 335
 336         acpi_hw_low_level_write(8, ACPI_EC_COMMAND_WRITE, &ec->command_addr);
 337         status = acpi_ec_wait(ec, ACPI_EC_EVENT_IBE);
 338         acpi_enable_gpe(NULL, ec->gpe_bit, ACPI_NOT_ISR);
 339         if (status){
 340                 goto end;
 341         }
 342
 343         acpi_hw_low_level_write(8, address, &ec->data_addr);
 344         status = acpi_ec_wait(ec, ACPI_EC_EVENT_IBE);
 345         if (status){
 346                 acpi_enable_gpe(NULL, ec->gpe_bit, ACPI_NOT_ISR);
 347                 goto end;
 348         }
 349
 350         acpi_hw_low_level_write(8, data, &ec->data_addr);
 351         status = acpi_ec_wait(ec, ACPI_EC_EVENT_IBE);
 352         acpi_enable_gpe(NULL, ec->gpe_bit, ACPI_NOT_ISR);
 353         if (status)
 354                 goto end;
 355
 356         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Wrote [%02x] to address [%02x]\n",
 357                 data, address));
 358
 359 end:
 360         acpi_ec_leave_burst_mode(ec);
 361         up(&ec->sem);
 362
 363         if (ec->global_lock)
 364                 acpi_release_global_lock(glk);
 365
 366         if(atomic_read(&ec->leaving_burst) == 2){
 367                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,"aborted, retry ...\n"));
 368                 while(!atomic_read(&ec->pending_gpe)){
 369                         msleep(1);
 370                 }
 371                 acpi_enable_gpe(NULL, ec->gpe_bit, ACPI_NOT_ISR);
 372                 goto retry;
 373         }
 374
 375         return_VALUE(status);
 376 }
 377
 378 /*
 379  * Externally callable EC access functions. For now, assume 1 EC only
 380  */
 381 int
 382 ec_read(u8 addr, u8 *val)
 383 {
 384         struct acpi_ec *ec;
 385         int err;
 386         u32 temp_data;
 387
 388         if (!first_ec)
 389                 return -ENODEV;
 390
 391         ec = acpi_driver_data(first_ec);
 392
 393         err = acpi_ec_read(ec, addr, &temp_data);
 394
 395         if (!err) {
 396                 *val = temp_data;
 397                 return 0;
 398         }
 399         else
 400                 return err;
 401 }
 402 EXPORT_SYMBOL(ec_read);
 403
 404 int
 405 ec_write(u8 addr, u8 val)
 406 {
 407         struct acpi_ec *ec;
 408         int err;
 409
 410         if (!first_ec)
 411                 return -ENODEV;
 412
 413         ec = acpi_driver_data(first_ec);
 414
 415         err = acpi_ec_write(ec, addr, val);
 416
 417         return err;
 418 }
 419 EXPORT_SYMBOL(ec_write);
 420
 421
 422 static int
 423 acpi_ec_query (
 424         struct acpi_ec          *ec,
 425         u32                     *data)
 426 {
 427         int                     status = 0;
 428         u32                     glk;
 429
 430         ACPI_FUNCTION_TRACE("acpi_ec_query");
 431
 432         if (!ec || !data)
 433                 return_VALUE(-EINVAL);
 434 retry:
 435         *data = 0;
 436
 437         if (ec->global_lock) {
 438                 status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk);
 439                 if (ACPI_FAILURE(status))
 440                         return_VALUE(-ENODEV);
 441         }
 442
 443         down(&ec->sem);
 444         if(acpi_ec_enter_burst_mode(ec))
 445                 goto end;
 446         /*
 447          * Query the EC to find out which _Qxx method we need to evaluate.
 448          * Note that successful completion of the query causes the ACPI_EC_SCI
 449          * bit to be cleared (and thus clearing the interrupt source).
 450          */
 451         acpi_hw_low_level_write(8, ACPI_EC_COMMAND_QUERY, &ec->command_addr);
 452         status = acpi_ec_wait(ec, ACPI_EC_EVENT_OBF);
 453         if (status){
 454                 acpi_enable_gpe(NULL, ec->gpe_bit, ACPI_NOT_ISR);
 455                 goto end;
 456         }
 457
 458         acpi_hw_low_level_read(8, data, &ec->data_addr);
 459         acpi_enable_gpe(NULL, ec->gpe_bit, ACPI_NOT_ISR);
 460         if (!*data)
 461                 status = -ENODATA;
 462
 463 end:
 464         acpi_ec_leave_burst_mode(ec);
 465         up(&ec->sem);
 466
 467         if (ec->global_lock)
 468                 acpi_release_global_lock(glk);
 469
 470         if(atomic_read(&ec->leaving_burst) == 2){
 471                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,"aborted, retry ...\n"));
 472                 while(!atomic_read(&ec->pending_gpe)){
 473                         msleep(1);
 474                 }
 475                 acpi_enable_gpe(NULL, ec->gpe_bit, ACPI_NOT_ISR);
 476                 goto retry;
 477         }
 478
 479         return_VALUE(status);
 480 }
 481
 482
 483 /* --------------------------------------------------------------------------
 484                                 Event Management
 485    -------------------------------------------------------------------------- */
 486
 487 struct acpi_ec_query_data {
 488         acpi_handle             handle;
 489         u8                      data;
 490 };
 491
 492 static void
 493 acpi_ec_gpe_query (
 494         void                    *ec_cxt)
 495 {
 496         struct acpi_ec          *ec = (struct acpi_ec *) ec_cxt;
 497         u32                     value;
 498         int                     result = -ENODATA;
 499         static char             object_name[5] = {'_','Q','0','0','\0'};
 500         const char              hex[] = {'0','1','2','3','4','5','6','7',
 501                                          '8','9','A','B','C','D','E','F'};
 502
 503         ACPI_FUNCTION_TRACE("acpi_ec_gpe_query");
 504
 505         if (acpi_ec_read_status(ec) & ACPI_EC_FLAG_SCI)
 506                 result = acpi_ec_query(ec, &value);
 507
 508         if (result)
 509                 goto end;
 510
 511         object_name[2] = hex[((value >> 4) & 0x0F)];
 512         object_name[3] = hex[(value & 0x0F)];
 513
 514         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Evaluating %s\n", object_name));
 515
 516         acpi_evaluate_object(ec->handle, object_name, NULL, NULL);
 517         atomic_dec(&ec->pending_gpe);
 518 end:
 519         return;
 520 }
 521
 522 static u32
 523 acpi_ec_gpe_handler (
 524         void                    *data)
 525 {
 526         acpi_status             status = AE_OK;
 527         u32                     value;
 528         struct acpi_ec          *ec = (struct acpi_ec *) data;
 529
 530         if (!ec)
 531                 return ACPI_INTERRUPT_NOT_HANDLED;
 532
 533         acpi_disable_gpe(NULL, ec->gpe_bit, ACPI_ISR);
 534
 535         value = acpi_ec_read_status(ec);
 536
 537         if((value & ACPI_EC_FLAG_IBF) &&
 538                 !(value & ACPI_EC_FLAG_BURST) &&
 539                         (atomic_read(&ec->leaving_burst) == 0)) {
 540         /*
 541          * the embedded controller disables
 542          * burst mode for any reason other
 543          * than the burst disable command
 544          * to process critical event.
 545          */
 546                 atomic_set(&ec->leaving_burst , 2); /* block current pending transaction
 547                                         and retry */
 548                 wake_up(&ec->wait);
 549         }else {
 550                 if ((ec->expect_event == ACPI_EC_EVENT_OBF &&
 551                                 (value & ACPI_EC_FLAG_OBF)) ||
 552                                 (ec->expect_event == ACPI_EC_EVENT_IBE &&
 553                                 !(value & ACPI_EC_FLAG_IBF))) {
 554                         ec->expect_event = 0;
 555                         wake_up(&ec->wait);
 556
 557                 }
 558         }
 559
 560         if (value & ACPI_EC_FLAG_SCI){
 561                 atomic_add(1, &ec->pending_gpe) ;
 562                 status = acpi_os_queue_for_execution(OSD_PRIORITY_GPE,
 563                                                 acpi_ec_gpe_query, ec);
 564         }
 565
 566         return status == AE_OK ?
 567                 ACPI_INTERRUPT_HANDLED : ACPI_INTERRUPT_NOT_HANDLED;
 568 }
 569
 570 /* --------------------------------------------------------------------------
 571                              Address Space Management
 572    -------------------------------------------------------------------------- */
 573
 574 static acpi_status
 575 acpi_ec_space_setup (
 576         acpi_handle             region_handle,
 577         u32                     function,
 578         void                    *handler_context,
 579         void                    **return_context)
 580 {
 581         /*
 582          * The EC object is in the handler context and is needed
 583          * when calling the acpi_ec_space_handler.
 584          */
 585         *return_context  = (function != ACPI_REGION_DEACTIVATE) ?
 586                                                 handler_context : NULL;
 587
 588         return AE_OK;
 589 }
 590
 591
 592 static acpi_status
 593 acpi_ec_space_handler (
 594         u32                     function,
 595         acpi_physical_address   address,
 596         u32                     bit_width,
 597         acpi_integer            *value,
 598         void                    *handler_context,
 599         void                    *region_context)
 600 {
 601         int                     result = 0;
 602         struct acpi_ec          *ec = NULL;
 603         u32                     temp = 0;
 604         acpi_integer            f_v = 0;
 605         int                     i = 0;
 606
 607         ACPI_FUNCTION_TRACE("acpi_ec_space_handler");
 608
 609         if ((address > 0xFF) || !value || !handler_context)
 610                 return_VALUE(AE_BAD_PARAMETER);
 611
 612         if(bit_width != 8) {
 613                 printk(KERN_WARNING PREFIX "acpi_ec_space_handler: bit_width should be 8\n");
 614                 if (acpi_strict)
 615                         return_VALUE(AE_BAD_PARAMETER);
 616         }
 617
 618         ec = (struct acpi_ec *) handler_context;
 619
 620 next_byte:
 621         switch (function) {
 622         case ACPI_READ:
 623                 result = acpi_ec_read(ec, (u8) address, &temp);
 624                 *value = (acpi_integer) temp;
 625                 break;
 626         case ACPI_WRITE:
 627                 result = acpi_ec_write(ec, (u8) address, (u8) *value);
 628                 break;
 629         default:
 630                 result = -EINVAL;
 631                 goto out;
 632                 break;
 633         }
 634
 635         bit_width -= 8;
 636         if(bit_width){
 637
 638                 if(function == ACPI_READ)
 639                         f_v |= (acpi_integer) (*value) << 8*i;
 640                 if(function == ACPI_WRITE)
 641                         (*value) >>=8;
 642                 i++;
 643                 goto next_byte;
 644         }
 645
 646
 647         if(function == ACPI_READ){
 648                 f_v |= (acpi_integer) (*value) << 8*i;
 649                 *value = f_v;
 650         }
 651
 652
 653 out:
 654         switch (result) {
 655         case -EINVAL:
 656                 return_VALUE(AE_BAD_PARAMETER);
 657                 break;
 658         case -ENODEV:
 659                 return_VALUE(AE_NOT_FOUND);
 660                 break;
 661         case -ETIME:
 662                 return_VALUE(AE_TIME);
 663                 break;
 664         default:
 665                 return_VALUE(AE_OK);
 666         }
 667
 668
 669 }
 670
 671
 672 /* --------------------------------------------------------------------------
 673                               FS Interface (/proc)
 674    -------------------------------------------------------------------------- */
 675
 676 static struct proc_dir_entry    *acpi_ec_dir;
 677
 678
 679 static int
 680 acpi_ec_read_info (struct seq_file *seq, void *offset)
 681 {
 682         struct acpi_ec          *ec = (struct acpi_ec *) seq->private;
 683
 684         ACPI_FUNCTION_TRACE("acpi_ec_read_info");
 685
 686         if (!ec)
 687                 goto end;
 688
 689         seq_printf(seq, "gpe bit:                 0x%02x\n",
 690                 (u32) ec->gpe_bit);
 691         seq_printf(seq, "ports:                   0x%02x, 0x%02x\n",
 692                 (u32) ec->status_addr.address, (u32) ec->data_addr.address);
 693         seq_printf(seq, "use global lock:         %s\n",
 694                 ec->global_lock?"yes":"no");
 695
 696 end:
 697         return_VALUE(0);
 698 }
 699
 700 static int acpi_ec_info_open_fs(struct inode *inode, struct file *file)
 701 {
 702         return single_open(file, acpi_ec_read_info, PDE(inode)->data);
 703 }
 704
 705 static struct file_operations acpi_ec_info_ops = {
 706         .open           = acpi_ec_info_open_fs,
 707         .read           = seq_read,
 708         .llseek         = seq_lseek,
 709         .release        = single_release,
 710         .owner = THIS_MODULE,
 711 };
 712
 713 static int
 714 acpi_ec_add_fs (
 715         struct acpi_device      *device)
 716 {
 717         struct proc_dir_entry   *entry;
 718
 719         ACPI_FUNCTION_TRACE("acpi_ec_add_fs");
 720
 721         if (!acpi_device_dir(device)) {
 722                 acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device),
 723                         acpi_ec_dir);
 724                 if (!acpi_device_dir(device))
 725                         return_VALUE(-ENODEV);
 726         }
 727
 728         entry = create_proc_entry(ACPI_EC_FILE_INFO, S_IRUGO,
 729                 acpi_device_dir(device));
 730         if (!entry)
 731                 ACPI_DEBUG_PRINT((ACPI_DB_WARN,
 732                         "Unable to create '%s' fs entry\n",
 733                         ACPI_EC_FILE_INFO));
 734         else {
 735                 entry->proc_fops = &acpi_ec_info_ops;
 736                 entry->data = acpi_driver_data(device);
 737                 entry->owner = THIS_MODULE;
 738         }
 739
 740         return_VALUE(0);
 741 }
 742
 743
 744 static int
 745 acpi_ec_remove_fs (
 746         struct acpi_device      *device)
 747 {
 748         ACPI_FUNCTION_TRACE("acpi_ec_remove_fs");
 749
 750         if (acpi_device_dir(device)) {
 751                 remove_proc_entry(ACPI_EC_FILE_INFO, acpi_device_dir(device));
 752                 remove_proc_entry(acpi_device_bid(device), acpi_ec_dir);
 753                 acpi_device_dir(device) = NULL;
 754         }
 755
 756         return_VALUE(0);
 757 }
 758
 759
 760 /* --------------------------------------------------------------------------
 761                                Driver Interface
 762    -------------------------------------------------------------------------- */
 763
 764 static int
 765 acpi_ec_add (
 766         struct acpi_device      *device)
 767 {
 768         int                     result;
 769         acpi_status             status;
 770         struct acpi_ec          *ec;
 771         unsigned long           uid;
 772
 773         ACPI_FUNCTION_TRACE("acpi_ec_add");
 774
 775         if (!device)
 776                 return_VALUE(-EINVAL);
 777
 778         ec = kmalloc(sizeof(struct acpi_ec), GFP_KERNEL);
 779         if (!ec)
 780                 return_VALUE(-ENOMEM);
 781         memset(ec, 0, sizeof(struct acpi_ec));
 782
 783         ec->handle = device->handle;
 784         ec->uid = -1;
 785         atomic_set(&ec->pending_gpe, 0);
 786         atomic_set(&ec->leaving_burst , 1);
 787         init_MUTEX(&ec->sem);
 788         init_waitqueue_head(&ec->wait);
 789         strcpy(acpi_device_name(device), ACPI_EC_DEVICE_NAME);
 790         strcpy(acpi_device_class(device), ACPI_EC_CLASS);
 791         acpi_driver_data(device) = ec;
 792
 793         /* Use the global lock for all EC transactions? */
 794         acpi_evaluate_integer(ec->handle, "_GLK", NULL, &ec->global_lock);
 795
 796         /* If our UID matches the UID for the ECDT-enumerated EC,
 797            we now have the *real* EC info, so kill the makeshift one.*/
 798         acpi_evaluate_integer(ec->handle, "_UID", NULL, &uid);
 799         if (ec_ecdt && ec_ecdt->uid == uid) {
 800                 acpi_remove_address_space_handler(ACPI_ROOT_OBJECT,
 801                         ACPI_ADR_SPACE_EC, &acpi_ec_space_handler);
 802
 803                 acpi_remove_gpe_handler(NULL, ec_ecdt->gpe_bit, &acpi_ec_gpe_handler);
 804
 805                 kfree(ec_ecdt);
 806         }
 807
 808         /* Get GPE bit assignment (EC events). */
 809         /* TODO: Add support for _GPE returning a package */
 810         status = acpi_evaluate_integer(ec->handle, "_GPE", NULL, &ec->gpe_bit);
 811         if (ACPI_FAILURE(status)) {
 812                 ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
 813                         "Error obtaining GPE bit assignment\n"));
 814                 result = -ENODEV;
 815                 goto end;
 816         }
 817
 818         result = acpi_ec_add_fs(device);
 819         if (result)
 820                 goto end;
 821
 822         printk(KERN_INFO PREFIX "%s [%s] (gpe %d)\n",
 823                 acpi_device_name(device), acpi_device_bid(device),
 824                 (u32) ec->gpe_bit);
 825
 826         if (!first_ec)
 827                 first_ec = device;
 828
 829 end:
 830         if (result)
 831                 kfree(ec);
 832
 833         return_VALUE(result);
 834 }
 835
 836
 837 static int
 838 acpi_ec_remove (
 839         struct acpi_device      *device,
 840         int                     type)
 841 {
 842         struct acpi_ec          *ec;
 843
 844         ACPI_FUNCTION_TRACE("acpi_ec_remove");
 845
 846         if (!device)
 847                 return_VALUE(-EINVAL);
 848
 849         ec = acpi_driver_data(device);
 850
 851         acpi_ec_remove_fs(device);
 852
 853         kfree(ec);
 854
 855         return_VALUE(0);
 856 }
 857
 858
 859 static acpi_status
 860 acpi_ec_io_ports (
 861         struct acpi_resource    *resource,
 862         void                    *context)
 863 {
 864         struct acpi_ec          *ec = (struct acpi_ec *) context;
 865         struct acpi_generic_address *addr;
 866
 867         if (resource->id != ACPI_RSTYPE_IO) {
 868                 return AE_OK;
 869         }
 870
 871         /*
 872          * The first address region returned is the data port, and
 873          * the second address region returned is the status/command
 874          * port.
 875          */
 876         if (ec->data_addr.register_bit_width == 0) {
 877                 addr = &ec->data_addr;
 878         } else if (ec->command_addr.register_bit_width == 0) {
 879                 addr = &ec->command_addr;
 880         } else {
 881                 return AE_CTRL_TERMINATE;
 882         }
 883
 884         addr->address_space_id = ACPI_ADR_SPACE_SYSTEM_IO;
 885         addr->register_bit_width = 8;
 886         addr->register_bit_offset = 0;
 887         addr->address = resource->data.io.min_base_address;
 888
 889         return AE_OK;
 890 }
 891
 892
 893 static int
 894 acpi_ec_start (
 895         struct acpi_device      *device)
 896 {
 897         acpi_status             status;
 898         struct acpi_ec          *ec;
 899
 900         ACPI_FUNCTION_TRACE("acpi_ec_start");
 901
 902         if (!device)
 903                 return_VALUE(-EINVAL);
 904
 905         ec = acpi_driver_data(device);
 906
 907         if (!ec)
 908                 return_VALUE(-EINVAL);
 909
 910         /*
 911          * Get I/O port addresses. Convert to GAS format.
 912          */
 913         status = acpi_walk_resources(ec->handle, METHOD_NAME__CRS,
 914                 acpi_ec_io_ports, ec);
 915         if (ACPI_FAILURE(status) || ec->command_addr.register_bit_width == 0) {
 916                 ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Error getting I/O port addresses"));
 917                 return_VALUE(-ENODEV);
 918         }
 919
 920         ec->status_addr = ec->command_addr;
 921
 922         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "gpe=0x%02x, ports=0x%2x,0x%2x\n",
 923                 (u32) ec->gpe_bit, (u32) ec->command_addr.address,
 924                 (u32) ec->data_addr.address));
 925
 926         /*
 927          * Install GPE handler
 928          */
 929         status = acpi_install_gpe_handler(NULL, ec->gpe_bit,
 930                 ACPI_GPE_EDGE_TRIGGERED, &acpi_ec_gpe_handler, ec);
 931         if (ACPI_FAILURE(status)) {
 932                 return_VALUE(-ENODEV);
 933         }
 934         acpi_set_gpe_type (NULL, ec->gpe_bit, ACPI_GPE_TYPE_RUNTIME);
 935         acpi_enable_gpe (NULL, ec->gpe_bit, ACPI_NOT_ISR);
 936
 937         status = acpi_install_address_space_handler (ec->handle,
 938                         ACPI_ADR_SPACE_EC, &acpi_ec_space_handler,
 939                         &acpi_ec_space_setup, ec);
 940         if (ACPI_FAILURE(status)) {
 941                 acpi_remove_gpe_handler(NULL, ec->gpe_bit, &acpi_ec_gpe_handler);
 942                 return_VALUE(-ENODEV);
 943         }
 944
 945         return_VALUE(AE_OK);
 946 }
 947
 948
 949 static int
 950 acpi_ec_stop (
 951         struct acpi_device      *device,
 952         int                     type)
 953 {
 954         acpi_status             status;
 955         struct acpi_ec          *ec;
 956
 957         ACPI_FUNCTION_TRACE("acpi_ec_stop");
 958
 959         if (!device)
 960                 return_VALUE(-EINVAL);
 961
 962         ec = acpi_driver_data(device);
 963
 964         status = acpi_remove_address_space_handler(ec->handle,
 965                 ACPI_ADR_SPACE_EC, &acpi_ec_space_handler);
 966         if (ACPI_FAILURE(status))
 967                 return_VALUE(-ENODEV);
 968
 969         status = acpi_remove_gpe_handler(NULL, ec->gpe_bit, &acpi_ec_gpe_handler);
 970         if (ACPI_FAILURE(status))
 971                 return_VALUE(-ENODEV);
 972
 973         return_VALUE(0);
 974 }
 975
 976 static acpi_status __init
 977 acpi_fake_ecdt_callback (
 978         acpi_handle     handle,
 979         u32             Level,
 980         void            *context,
 981         void            **retval)
 982 {
 983         acpi_status     status;
 984
 985         status = acpi_walk_resources(handle, METHOD_NAME__CRS,
 986                 acpi_ec_io_ports, ec_ecdt);
 987         if (ACPI_FAILURE(status))
 988                 return status;
 989         ec_ecdt->status_addr = ec_ecdt->command_addr;
 990
 991         ec_ecdt->uid = -1;
 992         acpi_evaluate_integer(handle, "_UID", NULL, &ec_ecdt->uid);
 993
 994         status = acpi_evaluate_integer(handle, "_GPE", NULL, &ec_ecdt->gpe_bit);
 995         if (ACPI_FAILURE(status))
 996                 return status;
 997         ec_ecdt->global_lock = TRUE;
 998         ec_ecdt->handle = handle;
 999
1000         printk(KERN_INFO PREFIX  "GPE=0x%02x, ports=0x%2x, 0x%2x\n",
1001                 (u32) ec_ecdt->gpe_bit, (u32) ec_ecdt->command_addr.address,
1002                 (u32) ec_ecdt->data_addr.address);
1003
1004         return AE_CTRL_TERMINATE;
1005 }
1006
1007 /*
1008  * Some BIOS (such as some from Gateway laptops) access EC region very early
1009  * such as in BAT0._INI or EC._INI before an EC device is found and
1010  * do not provide an ECDT. According to ACPI spec, ECDT isn't mandatorily
1011  * required, but if EC regison is accessed early, it is required.
1012  * The routine tries to workaround the BIOS bug by pre-scan EC device
1013  * It assumes that _CRS, _HID, _GPE, _UID methods of EC don't touch any
1014  * op region (since _REG isn't invoked yet). The assumption is true for
1015  * all systems found.
1016  */
1017 static int __init
1018 acpi_ec_fake_ecdt(void)
1019 {
1020         acpi_status     status;
1021         int             ret = 0;
1022
1023         printk(KERN_INFO PREFIX "Try to make an fake ECDT\n");
1024
1025         ec_ecdt = kmalloc(sizeof(struct acpi_ec), GFP_KERNEL);
1026         if (!ec_ecdt) {
1027                 ret = -ENOMEM;
1028                 goto error;
1029         }
1030         memset(ec_ecdt, 0, sizeof(struct acpi_ec));
1031
1032         status = acpi_get_devices (ACPI_EC_HID,
1033                                 acpi_fake_ecdt_callback,
1034                                 NULL,
1035                                 NULL);
1036         if (ACPI_FAILURE(status)) {
1037                 kfree(ec_ecdt);
1038                 ec_ecdt = NULL;
1039                 ret = -ENODEV;
1040                 goto error;
1041         }
1042         return 0;
1043 error:
1044         printk(KERN_ERR PREFIX "Can't make an fake ECDT\n");
1045         return ret;
1046 }
1047
1048 static int __init
1049 acpi_ec_get_real_ecdt(void)
1050 {
1051         acpi_status             status;
1052         struct acpi_table_ecdt  *ecdt_ptr;
1053
1054         status = acpi_get_firmware_table("ECDT", 1, ACPI_LOGICAL_ADDRESSING,
1055                 (struct acpi_table_header **) &ecdt_ptr);
1056         if (ACPI_FAILURE(status))
1057                 return -ENODEV;
1058
1059         printk(KERN_INFO PREFIX "Found ECDT\n");
1060
1061         /*
1062          * Generate a temporary ec context to use until the namespace is scanned
1063          */
1064         ec_ecdt = kmalloc(sizeof(struct acpi_ec), GFP_KERNEL);
1065         if (!ec_ecdt)
1066                 return -ENOMEM;
1067         memset(ec_ecdt, 0, sizeof(struct acpi_ec));
1068
1069         init_MUTEX(&ec_ecdt->sem);
1070         init_waitqueue_head(&ec_ecdt->wait);
1071         ec_ecdt->command_addr = ecdt_ptr->ec_control;
1072         ec_ecdt->status_addr = ecdt_ptr->ec_control;
1073         ec_ecdt->data_addr = ecdt_ptr->ec_data;
1074         ec_ecdt->gpe_bit = ecdt_ptr->gpe_bit;
1075         /* use the GL just to be safe */
1076         ec_ecdt->global_lock = TRUE;
1077         ec_ecdt->uid = ecdt_ptr->uid;
1078
1079         status = acpi_get_handle(NULL, ecdt_ptr->ec_id, &ec_ecdt->handle);
1080         if (ACPI_FAILURE(status)) {
1081                 goto error;
1082         }
1083
1084         return 0;
1085 error:
1086         printk(KERN_ERR PREFIX "Could not use ECDT\n");
1087         kfree(ec_ecdt);
1088         ec_ecdt = NULL;
1089
1090         return -ENODEV;
1091 }
1092
1093 static int __initdata acpi_fake_ecdt_enabled;
1094 int __init
1095 acpi_ec_ecdt_probe (void)
1096 {
1097         acpi_status             status;
1098         int                     ret;
1099
1100         ret = acpi_ec_get_real_ecdt();
1101         /* Try to make a fake ECDT */
1102         if (ret && acpi_fake_ecdt_enabled) {
1103                 ret = acpi_ec_fake_ecdt();
1104         }
1105
1106         if (ret)
1107                 return 0;
1108
1109         /*
1110          * Install GPE handler
1111          */
1112         status = acpi_install_gpe_handler(NULL, ec_ecdt->gpe_bit,
1113                 ACPI_GPE_EDGE_TRIGGERED, &acpi_ec_gpe_handler,
1114                 ec_ecdt);
1115         if (ACPI_FAILURE(status)) {
1116                 goto error;
1117         }
1118         acpi_set_gpe_type (NULL, ec_ecdt->gpe_bit, ACPI_GPE_TYPE_RUNTIME);
1119         acpi_enable_gpe (NULL, ec_ecdt->gpe_bit, ACPI_NOT_ISR);
1120
1121         status = acpi_install_address_space_handler (ACPI_ROOT_OBJECT,
1122                         ACPI_ADR_SPACE_EC, &acpi_ec_space_handler,
1123                         &acpi_ec_space_setup, ec_ecdt);
1124         if (ACPI_FAILURE(status)) {
1125                 acpi_remove_gpe_handler(NULL, ec_ecdt->gpe_bit,
1126                         &acpi_ec_gpe_handler);
1127                 goto error;
1128         }
1129
1130         return 0;
1131
1132 error:
1133         printk(KERN_ERR PREFIX "Could not use ECDT\n");
1134         kfree(ec_ecdt);
1135         ec_ecdt = NULL;
1136
1137         return -ENODEV;
1138 }
1139
1140
1141 static int __init acpi_ec_init (void)
1142 {
1143         int                     result;
1144
1145         ACPI_FUNCTION_TRACE("acpi_ec_init");
1146
1147         if (acpi_disabled)
1148                 return_VALUE(0);
1149
1150         acpi_ec_dir = proc_mkdir(ACPI_EC_CLASS, acpi_root_dir);
1151         if (!acpi_ec_dir)
1152                 return_VALUE(-ENODEV);
1153
1154         /* Now register the driver for the EC */
1155         result = acpi_bus_register_driver(&acpi_ec_driver);
1156         if (result < 0) {
1157                 remove_proc_entry(ACPI_EC_CLASS, acpi_root_dir);
1158                 return_VALUE(-ENODEV);
1159         }
1160
1161         return_VALUE(result);
1162 }
1163
1164 subsys_initcall(acpi_ec_init);
1165
1166 /* EC driver currently not unloadable */
1167 #if 0
1168 static void __exit
1169 acpi_ec_exit (void)
1170 {
1171         ACPI_FUNCTION_TRACE("acpi_ec_exit");
1172
1173         acpi_bus_unregister_driver(&acpi_ec_driver);
1174
1175         remove_proc_entry(ACPI_EC_CLASS, acpi_root_dir);
1176
1177         return_VOID;
1178 }
1179 #endif /* 0 */
1180
1181 static int __init acpi_fake_ecdt_setup(char *str)
1182 {
1183         acpi_fake_ecdt_enabled = 1;
1184         return 0;
1185 }
1186 __setup("acpi_fake_ecdt", acpi_fake_ecdt_setup);