Pileus Git - ~andy/linux/blob - 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         u64                     temp = *value;
 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 && acpi_strict) {
 613                 printk(KERN_WARNING PREFIX "acpi_ec_space_handler: bit_width should be 8\n");
 614                 return_VALUE(AE_BAD_PARAMETER);
 615         }
 616
 617         ec = (struct acpi_ec *) handler_context;
 618
 619 next_byte:
 620         switch (function) {
 621         case ACPI_READ:
 622                 temp = 0;
 623                 result = acpi_ec_read(ec, (u8) address, (u32 *)&temp);
 624                 break;
 625         case ACPI_WRITE:
 626                 result = acpi_ec_write(ec, (u8) address, (u8) temp);
 627                 break;
 628         default:
 629                 result = -EINVAL;
 630                 goto out;
 631                 break;
 632         }
 633
 634         bit_width -= 8;
 635         if (bit_width) {
 636                 if (function == ACPI_READ)
 637                         f_v |= temp << 8 * i;
 638                 if (function == ACPI_WRITE)
 639                         temp >>= 8;
 640                 i++;
 641                 address++;
 642                 goto next_byte;
 643         }
 644
 645         if (function == ACPI_READ) {
 646                 f_v |= temp << 8 * i;
 647                 *value = f_v;
 648         }
 649
 650
 651 out:
 652         switch (result) {
 653         case -EINVAL:
 654                 return_VALUE(AE_BAD_PARAMETER);
 655                 break;
 656         case -ENODEV:
 657                 return_VALUE(AE_NOT_FOUND);
 658                 break;
 659         case -ETIME:
 660                 return_VALUE(AE_TIME);
 661                 break;
 662         default:
 663                 return_VALUE(AE_OK);
 664         }
 665 }
 666
 667
 668 /* --------------------------------------------------------------------------
 669                               FS Interface (/proc)
 670    -------------------------------------------------------------------------- */
 671
 672 static struct proc_dir_entry    *acpi_ec_dir;
 673
 674
 675 static int
 676 acpi_ec_read_info (struct seq_file *seq, void *offset)
 677 {
 678         struct acpi_ec          *ec = (struct acpi_ec *) seq->private;
 679
 680         ACPI_FUNCTION_TRACE("acpi_ec_read_info");
 681
 682         if (!ec)
 683                 goto end;
 684
 685         seq_printf(seq, "gpe bit:                 0x%02x\n",
 686                 (u32) ec->gpe_bit);
 687         seq_printf(seq, "ports:                   0x%02x, 0x%02x\n",
 688                 (u32) ec->status_addr.address, (u32) ec->data_addr.address);
 689         seq_printf(seq, "use global lock:         %s\n",
 690                 ec->global_lock?"yes":"no");
 691
 692 end:
 693         return_VALUE(0);
 694 }
 695
 696 static int acpi_ec_info_open_fs(struct inode *inode, struct file *file)
 697 {
 698         return single_open(file, acpi_ec_read_info, PDE(inode)->data);
 699 }
 700
 701 static struct file_operations acpi_ec_info_ops = {
 702         .open           = acpi_ec_info_open_fs,
 703         .read           = seq_read,
 704         .llseek         = seq_lseek,
 705         .release        = single_release,
 706         .owner = THIS_MODULE,
 707 };
 708
 709 static int
 710 acpi_ec_add_fs (
 711         struct acpi_device      *device)
 712 {
 713         struct proc_dir_entry   *entry;
 714
 715         ACPI_FUNCTION_TRACE("acpi_ec_add_fs");
 716
 717         if (!acpi_device_dir(device)) {
 718                 acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device),
 719                         acpi_ec_dir);
 720                 if (!acpi_device_dir(device))
 721                         return_VALUE(-ENODEV);
 722         }
 723
 724         entry = create_proc_entry(ACPI_EC_FILE_INFO, S_IRUGO,
 725                 acpi_device_dir(device));
 726         if (!entry)
 727                 ACPI_DEBUG_PRINT((ACPI_DB_WARN,
 728                         "Unable to create '%s' fs entry\n",
 729                         ACPI_EC_FILE_INFO));
 730         else {
 731                 entry->proc_fops = &acpi_ec_info_ops;
 732                 entry->data = acpi_driver_data(device);
 733                 entry->owner = THIS_MODULE;
 734         }
 735
 736         return_VALUE(0);
 737 }
 738
 739
 740 static int
 741 acpi_ec_remove_fs (
 742         struct acpi_device      *device)
 743 {
 744         ACPI_FUNCTION_TRACE("acpi_ec_remove_fs");
 745
 746         if (acpi_device_dir(device)) {
 747                 remove_proc_entry(ACPI_EC_FILE_INFO, acpi_device_dir(device));
 748                 remove_proc_entry(acpi_device_bid(device), acpi_ec_dir);
 749                 acpi_device_dir(device) = NULL;
 750         }
 751
 752         return_VALUE(0);
 753 }
 754
 755
 756 /* --------------------------------------------------------------------------
 757                                Driver Interface
 758    -------------------------------------------------------------------------- */
 759
 760 static int
 761 acpi_ec_add (
 762         struct acpi_device      *device)
 763 {
 764         int                     result;
 765         acpi_status             status;
 766         struct acpi_ec          *ec;
 767         unsigned long           uid;
 768
 769         ACPI_FUNCTION_TRACE("acpi_ec_add");
 770
 771         if (!device)
 772                 return_VALUE(-EINVAL);
 773
 774         ec = kmalloc(sizeof(struct acpi_ec), GFP_KERNEL);
 775         if (!ec)
 776                 return_VALUE(-ENOMEM);
 777         memset(ec, 0, sizeof(struct acpi_ec));
 778
 779         ec->handle = device->handle;
 780         ec->uid = -1;
 781         atomic_set(&ec->pending_gpe, 0);
 782         atomic_set(&ec->leaving_burst , 1);
 783         init_MUTEX(&ec->sem);
 784         init_waitqueue_head(&ec->wait);
 785         strcpy(acpi_device_name(device), ACPI_EC_DEVICE_NAME);
 786         strcpy(acpi_device_class(device), ACPI_EC_CLASS);
 787         acpi_driver_data(device) = ec;
 788
 789         /* Use the global lock for all EC transactions? */
 790         acpi_evaluate_integer(ec->handle, "_GLK", NULL, &ec->global_lock);
 791
 792         /* If our UID matches the UID for the ECDT-enumerated EC,
 793            we now have the *real* EC info, so kill the makeshift one.*/
 794         acpi_evaluate_integer(ec->handle, "_UID", NULL, &uid);
 795         if (ec_ecdt && ec_ecdt->uid == uid) {
 796                 acpi_remove_address_space_handler(ACPI_ROOT_OBJECT,
 797                         ACPI_ADR_SPACE_EC, &acpi_ec_space_handler);
 798
 799                 acpi_remove_gpe_handler(NULL, ec_ecdt->gpe_bit, &acpi_ec_gpe_handler);
 800
 801                 kfree(ec_ecdt);
 802         }
 803
 804         /* Get GPE bit assignment (EC events). */
 805         /* TODO: Add support for _GPE returning a package */
 806         status = acpi_evaluate_integer(ec->handle, "_GPE", NULL, &ec->gpe_bit);
 807         if (ACPI_FAILURE(status)) {
 808                 ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
 809                         "Error obtaining GPE bit assignment\n"));
 810                 result = -ENODEV;
 811                 goto end;
 812         }
 813
 814         result = acpi_ec_add_fs(device);
 815         if (result)
 816                 goto end;
 817
 818         printk(KERN_INFO PREFIX "%s [%s] (gpe %d)\n",
 819                 acpi_device_name(device), acpi_device_bid(device),
 820                 (u32) ec->gpe_bit);
 821
 822         if (!first_ec)
 823                 first_ec = device;
 824
 825 end:
 826         if (result)
 827                 kfree(ec);
 828
 829         return_VALUE(result);
 830 }
 831
 832
 833 static int
 834 acpi_ec_remove (
 835         struct acpi_device      *device,
 836         int                     type)
 837 {
 838         struct acpi_ec          *ec;
 839
 840         ACPI_FUNCTION_TRACE("acpi_ec_remove");
 841
 842         if (!device)
 843                 return_VALUE(-EINVAL);
 844
 845         ec = acpi_driver_data(device);
 846
 847         acpi_ec_remove_fs(device);
 848
 849         kfree(ec);
 850
 851         return_VALUE(0);
 852 }
 853
 854
 855 static acpi_status
 856 acpi_ec_io_ports (
 857         struct acpi_resource    *resource,
 858         void                    *context)
 859 {
 860         struct acpi_ec          *ec = (struct acpi_ec *) context;
 861         struct acpi_generic_address *addr;
 862
 863         if (resource->id != ACPI_RSTYPE_IO) {
 864                 return AE_OK;
 865         }
 866
 867         /*
 868          * The first address region returned is the data port, and
 869          * the second address region returned is the status/command
 870          * port.
 871          */
 872         if (ec->data_addr.register_bit_width == 0) {
 873                 addr = &ec->data_addr;
 874         } else if (ec->command_addr.register_bit_width == 0) {
 875                 addr = &ec->command_addr;
 876         } else {
 877                 return AE_CTRL_TERMINATE;
 878         }
 879
 880         addr->address_space_id = ACPI_ADR_SPACE_SYSTEM_IO;
 881         addr->register_bit_width = 8;
 882         addr->register_bit_offset = 0;
 883         addr->address = resource->data.io.min_base_address;
 884
 885         return AE_OK;
 886 }
 887
 888
 889 static int
 890 acpi_ec_start (
 891         struct acpi_device      *device)
 892 {
 893         acpi_status             status;
 894         struct acpi_ec          *ec;
 895
 896         ACPI_FUNCTION_TRACE("acpi_ec_start");
 897
 898         if (!device)
 899                 return_VALUE(-EINVAL);
 900
 901         ec = acpi_driver_data(device);
 902
 903         if (!ec)
 904                 return_VALUE(-EINVAL);
 905
 906         /*
 907          * Get I/O port addresses. Convert to GAS format.
 908          */
 909         status = acpi_walk_resources(ec->handle, METHOD_NAME__CRS,
 910                 acpi_ec_io_ports, ec);
 911         if (ACPI_FAILURE(status) || ec->command_addr.register_bit_width == 0) {
 912                 ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Error getting I/O port addresses"));
 913                 return_VALUE(-ENODEV);
 914         }
 915
 916         ec->status_addr = ec->command_addr;
 917
 918         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "gpe=0x%02x, ports=0x%2x,0x%2x\n",
 919                 (u32) ec->gpe_bit, (u32) ec->command_addr.address,
 920                 (u32) ec->data_addr.address));
 921
 922         /*
 923          * Install GPE handler
 924          */
 925         status = acpi_install_gpe_handler(NULL, ec->gpe_bit,
 926                 ACPI_GPE_EDGE_TRIGGERED, &acpi_ec_gpe_handler, ec);
 927         if (ACPI_FAILURE(status)) {
 928                 return_VALUE(-ENODEV);
 929         }
 930         acpi_set_gpe_type (NULL, ec->gpe_bit, ACPI_GPE_TYPE_RUNTIME);
 931         acpi_enable_gpe (NULL, ec->gpe_bit, ACPI_NOT_ISR);
 932
 933         status = acpi_install_address_space_handler (ec->handle,
 934                         ACPI_ADR_SPACE_EC, &acpi_ec_space_handler,
 935                         &acpi_ec_space_setup, ec);
 936         if (ACPI_FAILURE(status)) {
 937                 acpi_remove_gpe_handler(NULL, ec->gpe_bit, &acpi_ec_gpe_handler);
 938                 return_VALUE(-ENODEV);
 939         }
 940
 941         return_VALUE(AE_OK);
 942 }
 943
 944
 945 static int
 946 acpi_ec_stop (
 947         struct acpi_device      *device,
 948         int                     type)
 949 {
 950         acpi_status             status;
 951         struct acpi_ec          *ec;
 952
 953         ACPI_FUNCTION_TRACE("acpi_ec_stop");
 954
 955         if (!device)
 956                 return_VALUE(-EINVAL);
 957
 958         ec = acpi_driver_data(device);
 959
 960         status = acpi_remove_address_space_handler(ec->handle,
 961                 ACPI_ADR_SPACE_EC, &acpi_ec_space_handler);
 962         if (ACPI_FAILURE(status))
 963                 return_VALUE(-ENODEV);
 964
 965         status = acpi_remove_gpe_handler(NULL, ec->gpe_bit, &acpi_ec_gpe_handler);
 966         if (ACPI_FAILURE(status))
 967                 return_VALUE(-ENODEV);
 968
 969         return_VALUE(0);
 970 }
 971
 972 static acpi_status __init
 973 acpi_fake_ecdt_callback (
 974         acpi_handle     handle,
 975         u32             Level,
 976         void            *context,
 977         void            **retval)
 978 {
 979         acpi_status     status;
 980
 981         status = acpi_walk_resources(handle, METHOD_NAME__CRS,
 982                 acpi_ec_io_ports, ec_ecdt);
 983         if (ACPI_FAILURE(status))
 984                 return status;
 985         ec_ecdt->status_addr = ec_ecdt->command_addr;
 986
 987         ec_ecdt->uid = -1;
 988         acpi_evaluate_integer(handle, "_UID", NULL, &ec_ecdt->uid);
 989
 990         status = acpi_evaluate_integer(handle, "_GPE", NULL, &ec_ecdt->gpe_bit);
 991         if (ACPI_FAILURE(status))
 992                 return status;
 993         ec_ecdt->global_lock = TRUE;
 994         ec_ecdt->handle = handle;
 995
 996         printk(KERN_INFO PREFIX  "GPE=0x%02x, ports=0x%2x, 0x%2x\n",
 997                 (u32) ec_ecdt->gpe_bit, (u32) ec_ecdt->command_addr.address,
 998                 (u32) ec_ecdt->data_addr.address);
 999
1000         return AE_CTRL_TERMINATE;
1001 }
1002
1003 /*
1004  * Some BIOS (such as some from Gateway laptops) access EC region very early
1005  * such as in BAT0._INI or EC._INI before an EC device is found and
1006  * do not provide an ECDT. According to ACPI spec, ECDT isn't mandatorily
1007  * required, but if EC regison is accessed early, it is required.
1008  * The routine tries to workaround the BIOS bug by pre-scan EC device
1009  * It assumes that _CRS, _HID, _GPE, _UID methods of EC don't touch any
1010  * op region (since _REG isn't invoked yet). The assumption is true for
1011  * all systems found.
1012  */
1013 static int __init
1014 acpi_ec_fake_ecdt(void)
1015 {
1016         acpi_status     status;
1017         int             ret = 0;
1018
1019         printk(KERN_INFO PREFIX "Try to make an fake ECDT\n");
1020
1021         ec_ecdt = kmalloc(sizeof(struct acpi_ec), GFP_KERNEL);
1022         if (!ec_ecdt) {
1023                 ret = -ENOMEM;
1024                 goto error;
1025         }
1026         memset(ec_ecdt, 0, sizeof(struct acpi_ec));
1027
1028         status = acpi_get_devices (ACPI_EC_HID,
1029                                 acpi_fake_ecdt_callback,
1030                                 NULL,
1031                                 NULL);
1032         if (ACPI_FAILURE(status)) {
1033                 kfree(ec_ecdt);
1034                 ec_ecdt = NULL;
1035                 ret = -ENODEV;
1036                 goto error;
1037         }
1038         return 0;
1039 error:
1040         printk(KERN_ERR PREFIX "Can't make an fake ECDT\n");
1041         return ret;
1042 }
1043
1044 static int __init
1045 acpi_ec_get_real_ecdt(void)
1046 {
1047         acpi_status             status;
1048         struct acpi_table_ecdt  *ecdt_ptr;
1049
1050         status = acpi_get_firmware_table("ECDT", 1, ACPI_LOGICAL_ADDRESSING,
1051                 (struct acpi_table_header **) &ecdt_ptr);
1052         if (ACPI_FAILURE(status))
1053                 return -ENODEV;
1054
1055         printk(KERN_INFO PREFIX "Found ECDT\n");
1056
1057         /*
1058          * Generate a temporary ec context to use until the namespace is scanned
1059          */
1060         ec_ecdt = kmalloc(sizeof(struct acpi_ec), GFP_KERNEL);
1061         if (!ec_ecdt)
1062                 return -ENOMEM;
1063         memset(ec_ecdt, 0, sizeof(struct acpi_ec));
1064
1065         init_MUTEX(&ec_ecdt->sem);
1066         init_waitqueue_head(&ec_ecdt->wait);
1067         ec_ecdt->command_addr = ecdt_ptr->ec_control;
1068         ec_ecdt->status_addr = ecdt_ptr->ec_control;
1069         ec_ecdt->data_addr = ecdt_ptr->ec_data;
1070         ec_ecdt->gpe_bit = ecdt_ptr->gpe_bit;
1071         /* use the GL just to be safe */
1072         ec_ecdt->global_lock = TRUE;
1073         ec_ecdt->uid = ecdt_ptr->uid;
1074
1075         status = acpi_get_handle(NULL, ecdt_ptr->ec_id, &ec_ecdt->handle);
1076         if (ACPI_FAILURE(status)) {
1077                 goto error;
1078         }
1079
1080         return 0;
1081 error:
1082         printk(KERN_ERR PREFIX "Could not use ECDT\n");
1083         kfree(ec_ecdt);
1084         ec_ecdt = NULL;
1085
1086         return -ENODEV;
1087 }
1088
1089 static int __initdata acpi_fake_ecdt_enabled;
1090 int __init
1091 acpi_ec_ecdt_probe (void)
1092 {
1093         acpi_status             status;
1094         int                     ret;
1095
1096         ret = acpi_ec_get_real_ecdt();
1097         /* Try to make a fake ECDT */
1098         if (ret && acpi_fake_ecdt_enabled) {
1099                 ret = acpi_ec_fake_ecdt();
1100         }
1101
1102         if (ret)
1103                 return 0;
1104
1105         /*
1106          * Install GPE handler
1107          */
1108         status = acpi_install_gpe_handler(NULL, ec_ecdt->gpe_bit,
1109                 ACPI_GPE_EDGE_TRIGGERED, &acpi_ec_gpe_handler,
1110                 ec_ecdt);
1111         if (ACPI_FAILURE(status)) {
1112                 goto error;
1113         }
1114         acpi_set_gpe_type (NULL, ec_ecdt->gpe_bit, ACPI_GPE_TYPE_RUNTIME);
1115         acpi_enable_gpe (NULL, ec_ecdt->gpe_bit, ACPI_NOT_ISR);
1116
1117         status = acpi_install_address_space_handler (ACPI_ROOT_OBJECT,
1118                         ACPI_ADR_SPACE_EC, &acpi_ec_space_handler,
1119                         &acpi_ec_space_setup, ec_ecdt);
1120         if (ACPI_FAILURE(status)) {
1121                 acpi_remove_gpe_handler(NULL, ec_ecdt->gpe_bit,
1122                         &acpi_ec_gpe_handler);
1123                 goto error;
1124         }
1125
1126         return 0;
1127
1128 error:
1129         printk(KERN_ERR PREFIX "Could not use ECDT\n");
1130         kfree(ec_ecdt);
1131         ec_ecdt = NULL;
1132
1133         return -ENODEV;
1134 }
1135
1136
1137 static int __init acpi_ec_init (void)
1138 {
1139         int                     result;
1140
1141         ACPI_FUNCTION_TRACE("acpi_ec_init");
1142
1143         if (acpi_disabled)
1144                 return_VALUE(0);
1145
1146         acpi_ec_dir = proc_mkdir(ACPI_EC_CLASS, acpi_root_dir);
1147         if (!acpi_ec_dir)
1148                 return_VALUE(-ENODEV);
1149
1150         /* Now register the driver for the EC */
1151         result = acpi_bus_register_driver(&acpi_ec_driver);
1152         if (result < 0) {
1153                 remove_proc_entry(ACPI_EC_CLASS, acpi_root_dir);
1154                 return_VALUE(-ENODEV);
1155         }
1156
1157         return_VALUE(result);
1158 }
1159
1160 subsys_initcall(acpi_ec_init);
1161
1162 /* EC driver currently not unloadable */
1163 #if 0
1164 static void __exit
1165 acpi_ec_exit (void)
1166 {
1167         ACPI_FUNCTION_TRACE("acpi_ec_exit");
1168
1169         acpi_bus_unregister_driver(&acpi_ec_driver);
1170
1171         remove_proc_entry(ACPI_EC_CLASS, acpi_root_dir);
1172
1173         return_VOID;
1174 }
1175 #endif /* 0 */
1176
1177 static int __init acpi_fake_ecdt_setup(char *str)
1178 {
1179         acpi_fake_ecdt_enabled = 1;
1180         return 0;
1181 }
1182 __setup("acpi_fake_ecdt", acpi_fake_ecdt_setup);