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         *data = 0;
 435
 436         if (ec->global_lock) {
 437                 status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk);
 438                 if (ACPI_FAILURE(status))
 439                         return_VALUE(-ENODEV);
 440         }
 441
 442         down(&ec->sem);
 443         if(acpi_ec_enter_burst_mode(ec))
 444                 goto end;
 445         /*
 446          * Query the EC to find out which _Qxx method we need to evaluate.
 447          * Note that successful completion of the query causes the ACPI_EC_SCI
 448          * bit to be cleared (and thus clearing the interrupt source).
 449          */
 450         acpi_hw_low_level_write(8, ACPI_EC_COMMAND_QUERY, &ec->command_addr);
 451         status = acpi_ec_wait(ec, ACPI_EC_EVENT_OBF);
 452         if (status){
 453                 acpi_enable_gpe(NULL, ec->gpe_bit, ACPI_NOT_ISR);
 454                 goto end;
 455         }
 456
 457         acpi_hw_low_level_read(8, data, &ec->data_addr);
 458         acpi_enable_gpe(NULL, ec->gpe_bit, ACPI_NOT_ISR);
 459         if (!*data)
 460                 status = -ENODATA;
 461
 462 end:
 463         acpi_ec_leave_burst_mode(ec);
 464         up(&ec->sem);
 465
 466         if (ec->global_lock)
 467                 acpi_release_global_lock(glk);
 468
 469         if(atomic_read(&ec->leaving_burst) == 2){
 470                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,"aborted, retry ...\n"));
 471                 acpi_enable_gpe(NULL, ec->gpe_bit, ACPI_NOT_ISR);
 472                 status = -ENODATA;
 473         }
 474         return_VALUE(status);
 475 }
 476
 477
 478 /* --------------------------------------------------------------------------
 479                                 Event Management
 480    -------------------------------------------------------------------------- */
 481
 482 struct acpi_ec_query_data {
 483         acpi_handle             handle;
 484         u8                      data;
 485 };
 486
 487 static void
 488 acpi_ec_gpe_query (
 489         void                    *ec_cxt)
 490 {
 491         struct acpi_ec          *ec = (struct acpi_ec *) ec_cxt;
 492         u32                     value;
 493         int                     result = -ENODATA;
 494         static char             object_name[5] = {'_','Q','0','0','\0'};
 495         const char              hex[] = {'0','1','2','3','4','5','6','7',
 496                                          '8','9','A','B','C','D','E','F'};
 497
 498         ACPI_FUNCTION_TRACE("acpi_ec_gpe_query");
 499
 500         if (acpi_ec_read_status(ec) & ACPI_EC_FLAG_SCI)
 501                 result = acpi_ec_query(ec, &value);
 502
 503         if (result)
 504                 goto end;
 505
 506         object_name[2] = hex[((value >> 4) & 0x0F)];
 507         object_name[3] = hex[(value & 0x0F)];
 508
 509         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Evaluating %s\n", object_name));
 510
 511         acpi_evaluate_object(ec->handle, object_name, NULL, NULL);
 512 end:
 513         atomic_dec(&ec->pending_gpe);
 514         return;
 515 }
 516
 517 static u32
 518 acpi_ec_gpe_handler (
 519         void                    *data)
 520 {
 521         acpi_status             status = AE_OK;
 522         u32                     value;
 523         struct acpi_ec          *ec = (struct acpi_ec *) data;
 524
 525         if (!ec)
 526                 return ACPI_INTERRUPT_NOT_HANDLED;
 527
 528         acpi_disable_gpe(NULL, ec->gpe_bit, ACPI_ISR);
 529
 530         value = acpi_ec_read_status(ec);
 531
 532         if((value & ACPI_EC_FLAG_IBF) &&
 533                 !(value & ACPI_EC_FLAG_BURST) &&
 534                         (atomic_read(&ec->leaving_burst) == 0)) {
 535         /*
 536          * the embedded controller disables
 537          * burst mode for any reason other
 538          * than the burst disable command
 539          * to process critical event.
 540          */
 541                 atomic_set(&ec->leaving_burst , 2); /* block current pending transaction
 542                                         and retry */
 543                 wake_up(&ec->wait);
 544         }else {
 545                 if ((ec->expect_event == ACPI_EC_EVENT_OBF &&
 546                                 (value & ACPI_EC_FLAG_OBF)) ||
 547                                 (ec->expect_event == ACPI_EC_EVENT_IBE &&
 548                                 !(value & ACPI_EC_FLAG_IBF))) {
 549                         ec->expect_event = 0;
 550                         wake_up(&ec->wait);
 551                         return ACPI_INTERRUPT_HANDLED;
 552                 }
 553         }
 554
 555         if (value & ACPI_EC_FLAG_SCI){
 556                 atomic_add(1, &ec->pending_gpe) ;
 557                 status = acpi_os_queue_for_execution(OSD_PRIORITY_GPE,
 558                                                 acpi_ec_gpe_query, ec);
 559                 return status == AE_OK ?
 560                 ACPI_INTERRUPT_HANDLED : ACPI_INTERRUPT_NOT_HANDLED;
 561         }
 562         acpi_enable_gpe(NULL, ec->gpe_bit, ACPI_ISR);
 563         return status == AE_OK ?
 564                 ACPI_INTERRUPT_HANDLED : ACPI_INTERRUPT_NOT_HANDLED;
 565 }
 566
 567 /* --------------------------------------------------------------------------
 568                              Address Space Management
 569    -------------------------------------------------------------------------- */
 570
 571 static acpi_status
 572 acpi_ec_space_setup (
 573         acpi_handle             region_handle,
 574         u32                     function,
 575         void                    *handler_context,
 576         void                    **return_context)
 577 {
 578         /*
 579          * The EC object is in the handler context and is needed
 580          * when calling the acpi_ec_space_handler.
 581          */
 582         *return_context  = (function != ACPI_REGION_DEACTIVATE) ?
 583                                                 handler_context : NULL;
 584
 585         return AE_OK;
 586 }
 587
 588
 589 static acpi_status
 590 acpi_ec_space_handler (
 591         u32                     function,
 592         acpi_physical_address   address,
 593         u32                     bit_width,
 594         acpi_integer            *value,
 595         void                    *handler_context,
 596         void                    *region_context)
 597 {
 598         int                     result = 0;
 599         struct acpi_ec          *ec = NULL;
 600         u64                     temp = *value;
 601         acpi_integer            f_v = 0;
 602         int                     i = 0;
 603
 604         ACPI_FUNCTION_TRACE("acpi_ec_space_handler");
 605
 606         if ((address > 0xFF) || !value || !handler_context)
 607                 return_VALUE(AE_BAD_PARAMETER);
 608
 609         if (bit_width != 8 && acpi_strict) {
 610                 printk(KERN_WARNING PREFIX "acpi_ec_space_handler: bit_width should be 8\n");
 611                 return_VALUE(AE_BAD_PARAMETER);
 612         }
 613
 614         ec = (struct acpi_ec *) handler_context;
 615
 616 next_byte:
 617         switch (function) {
 618         case ACPI_READ:
 619                 temp = 0;
 620                 result = acpi_ec_read(ec, (u8) address, (u32 *)&temp);
 621                 break;
 622         case ACPI_WRITE:
 623                 result = acpi_ec_write(ec, (u8) address, (u8) temp);
 624                 break;
 625         default:
 626                 result = -EINVAL;
 627                 goto out;
 628                 break;
 629         }
 630
 631         bit_width -= 8;
 632         if (bit_width) {
 633                 if (function == ACPI_READ)
 634                         f_v |= temp << 8 * i;
 635                 if (function == ACPI_WRITE)
 636                         temp >>= 8;
 637                 i++;
 638                 address++;
 639                 goto next_byte;
 640         }
 641
 642         if (function == ACPI_READ) {
 643                 f_v |= temp << 8 * i;
 644                 *value = f_v;
 645         }
 646
 647
 648 out:
 649         switch (result) {
 650         case -EINVAL:
 651                 return_VALUE(AE_BAD_PARAMETER);
 652                 break;
 653         case -ENODEV:
 654                 return_VALUE(AE_NOT_FOUND);
 655                 break;
 656         case -ETIME:
 657                 return_VALUE(AE_TIME);
 658                 break;
 659         default:
 660                 return_VALUE(AE_OK);
 661         }
 662 }
 663
 664
 665 /* --------------------------------------------------------------------------
 666                               FS Interface (/proc)
 667    -------------------------------------------------------------------------- */
 668
 669 static struct proc_dir_entry    *acpi_ec_dir;
 670
 671
 672 static int
 673 acpi_ec_read_info (struct seq_file *seq, void *offset)
 674 {
 675         struct acpi_ec          *ec = (struct acpi_ec *) seq->private;
 676
 677         ACPI_FUNCTION_TRACE("acpi_ec_read_info");
 678
 679         if (!ec)
 680                 goto end;
 681
 682         seq_printf(seq, "gpe bit:                 0x%02x\n",
 683                 (u32) ec->gpe_bit);
 684         seq_printf(seq, "ports:                   0x%02x, 0x%02x\n",
 685                 (u32) ec->status_addr.address, (u32) ec->data_addr.address);
 686         seq_printf(seq, "use global lock:         %s\n",
 687                 ec->global_lock?"yes":"no");
 688         acpi_enable_gpe(NULL, ec->gpe_bit, ACPI_NOT_ISR);
 689
 690 end:
 691         return_VALUE(0);
 692 }
 693
 694 static int acpi_ec_info_open_fs(struct inode *inode, struct file *file)
 695 {
 696         return single_open(file, acpi_ec_read_info, PDE(inode)->data);
 697 }
 698
 699 static struct file_operations acpi_ec_info_ops = {
 700         .open           = acpi_ec_info_open_fs,
 701         .read           = seq_read,
 702         .llseek         = seq_lseek,
 703         .release        = single_release,
 704         .owner = THIS_MODULE,
 705 };
 706
 707 static int
 708 acpi_ec_add_fs (
 709         struct acpi_device      *device)
 710 {
 711         struct proc_dir_entry   *entry;
 712
 713         ACPI_FUNCTION_TRACE("acpi_ec_add_fs");
 714
 715         if (!acpi_device_dir(device)) {
 716                 acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device),
 717                         acpi_ec_dir);
 718                 if (!acpi_device_dir(device))
 719                         return_VALUE(-ENODEV);
 720         }
 721
 722         entry = create_proc_entry(ACPI_EC_FILE_INFO, S_IRUGO,
 723                 acpi_device_dir(device));
 724         if (!entry)
 725                 ACPI_DEBUG_PRINT((ACPI_DB_WARN,
 726                         "Unable to create '%s' fs entry\n",
 727                         ACPI_EC_FILE_INFO));
 728         else {
 729                 entry->proc_fops = &acpi_ec_info_ops;
 730                 entry->data = acpi_driver_data(device);
 731                 entry->owner = THIS_MODULE;
 732         }
 733
 734         return_VALUE(0);
 735 }
 736
 737
 738 static int
 739 acpi_ec_remove_fs (
 740         struct acpi_device      *device)
 741 {
 742         ACPI_FUNCTION_TRACE("acpi_ec_remove_fs");
 743
 744         if (acpi_device_dir(device)) {
 745                 remove_proc_entry(ACPI_EC_FILE_INFO, acpi_device_dir(device));
 746                 remove_proc_entry(acpi_device_bid(device), acpi_ec_dir);
 747                 acpi_device_dir(device) = NULL;
 748         }
 749
 750         return_VALUE(0);
 751 }
 752
 753
 754 /* --------------------------------------------------------------------------
 755                                Driver Interface
 756    -------------------------------------------------------------------------- */
 757
 758 static int
 759 acpi_ec_add (
 760         struct acpi_device      *device)
 761 {
 762         int                     result;
 763         acpi_status             status;
 764         struct acpi_ec          *ec;
 765         unsigned long           uid;
 766
 767         ACPI_FUNCTION_TRACE("acpi_ec_add");
 768
 769         if (!device)
 770                 return_VALUE(-EINVAL);
 771
 772         ec = kmalloc(sizeof(struct acpi_ec), GFP_KERNEL);
 773         if (!ec)
 774                 return_VALUE(-ENOMEM);
 775         memset(ec, 0, sizeof(struct acpi_ec));
 776
 777         ec->handle = device->handle;
 778         ec->uid = -1;
 779         atomic_set(&ec->pending_gpe, 0);
 780         atomic_set(&ec->leaving_burst , 1);
 781         init_MUTEX(&ec->sem);
 782         init_waitqueue_head(&ec->wait);
 783         strcpy(acpi_device_name(device), ACPI_EC_DEVICE_NAME);
 784         strcpy(acpi_device_class(device), ACPI_EC_CLASS);
 785         acpi_driver_data(device) = ec;
 786
 787         /* Use the global lock for all EC transactions? */
 788         acpi_evaluate_integer(ec->handle, "_GLK", NULL, &ec->global_lock);
 789
 790         /* If our UID matches the UID for the ECDT-enumerated EC,
 791            we now have the *real* EC info, so kill the makeshift one.*/
 792         acpi_evaluate_integer(ec->handle, "_UID", NULL, &uid);
 793         if (ec_ecdt && ec_ecdt->uid == uid) {
 794                 acpi_remove_address_space_handler(ACPI_ROOT_OBJECT,
 795                         ACPI_ADR_SPACE_EC, &acpi_ec_space_handler);
 796
 797                 acpi_remove_gpe_handler(NULL, ec_ecdt->gpe_bit, &acpi_ec_gpe_handler);
 798
 799                 kfree(ec_ecdt);
 800         }
 801
 802         /* Get GPE bit assignment (EC events). */
 803         /* TODO: Add support for _GPE returning a package */
 804         status = acpi_evaluate_integer(ec->handle, "_GPE", NULL, &ec->gpe_bit);
 805         if (ACPI_FAILURE(status)) {
 806                 ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
 807                         "Error obtaining GPE bit assignment\n"));
 808                 result = -ENODEV;
 809                 goto end;
 810         }
 811
 812         result = acpi_ec_add_fs(device);
 813         if (result)
 814                 goto end;
 815
 816         printk(KERN_INFO PREFIX "%s [%s] (gpe %d)\n",
 817                 acpi_device_name(device), acpi_device_bid(device),
 818                 (u32) ec->gpe_bit);
 819
 820         if (!first_ec)
 821                 first_ec = device;
 822
 823 end:
 824         if (result)
 825                 kfree(ec);
 826
 827         return_VALUE(result);
 828 }
 829
 830
 831 static int
 832 acpi_ec_remove (
 833         struct acpi_device      *device,
 834         int                     type)
 835 {
 836         struct acpi_ec          *ec;
 837
 838         ACPI_FUNCTION_TRACE("acpi_ec_remove");
 839
 840         if (!device)
 841                 return_VALUE(-EINVAL);
 842
 843         ec = acpi_driver_data(device);
 844
 845         acpi_ec_remove_fs(device);
 846
 847         kfree(ec);
 848
 849         return_VALUE(0);
 850 }
 851
 852
 853 static acpi_status
 854 acpi_ec_io_ports (
 855         struct acpi_resource    *resource,
 856         void                    *context)
 857 {
 858         struct acpi_ec          *ec = (struct acpi_ec *) context;
 859         struct acpi_generic_address *addr;
 860
 861         if (resource->id != ACPI_RSTYPE_IO) {
 862                 return AE_OK;
 863         }
 864
 865         /*
 866          * The first address region returned is the data port, and
 867          * the second address region returned is the status/command
 868          * port.
 869          */
 870         if (ec->data_addr.register_bit_width == 0) {
 871                 addr = &ec->data_addr;
 872         } else if (ec->command_addr.register_bit_width == 0) {
 873                 addr = &ec->command_addr;
 874         } else {
 875                 return AE_CTRL_TERMINATE;
 876         }
 877
 878         addr->address_space_id = ACPI_ADR_SPACE_SYSTEM_IO;
 879         addr->register_bit_width = 8;
 880         addr->register_bit_offset = 0;
 881         addr->address = resource->data.io.min_base_address;
 882
 883         return AE_OK;
 884 }
 885
 886
 887 static int
 888 acpi_ec_start (
 889         struct acpi_device      *device)
 890 {
 891         acpi_status             status;
 892         struct acpi_ec          *ec;
 893
 894         ACPI_FUNCTION_TRACE("acpi_ec_start");
 895
 896         if (!device)
 897                 return_VALUE(-EINVAL);
 898
 899         ec = acpi_driver_data(device);
 900
 901         if (!ec)
 902                 return_VALUE(-EINVAL);
 903
 904         /*
 905          * Get I/O port addresses. Convert to GAS format.
 906          */
 907         status = acpi_walk_resources(ec->handle, METHOD_NAME__CRS,
 908                 acpi_ec_io_ports, ec);
 909         if (ACPI_FAILURE(status) || ec->command_addr.register_bit_width == 0) {
 910                 ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Error getting I/O port addresses"));
 911                 return_VALUE(-ENODEV);
 912         }
 913
 914         ec->status_addr = ec->command_addr;
 915
 916         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "gpe=0x%02x, ports=0x%2x,0x%2x\n",
 917                 (u32) ec->gpe_bit, (u32) ec->command_addr.address,
 918                 (u32) ec->data_addr.address));
 919
 920         /*
 921          * Install GPE handler
 922          */
 923         status = acpi_install_gpe_handler(NULL, ec->gpe_bit,
 924                 ACPI_GPE_EDGE_TRIGGERED, &acpi_ec_gpe_handler, ec);
 925         if (ACPI_FAILURE(status)) {
 926                 return_VALUE(-ENODEV);
 927         }
 928         acpi_set_gpe_type (NULL, ec->gpe_bit, ACPI_GPE_TYPE_RUNTIME);
 929         acpi_enable_gpe (NULL, ec->gpe_bit, ACPI_NOT_ISR);
 930
 931         status = acpi_install_address_space_handler (ec->handle,
 932                         ACPI_ADR_SPACE_EC, &acpi_ec_space_handler,
 933                         &acpi_ec_space_setup, ec);
 934         if (ACPI_FAILURE(status)) {
 935                 acpi_remove_gpe_handler(NULL, ec->gpe_bit, &acpi_ec_gpe_handler);
 936                 return_VALUE(-ENODEV);
 937         }
 938
 939         return_VALUE(AE_OK);
 940 }
 941
 942
 943 static int
 944 acpi_ec_stop (
 945         struct acpi_device      *device,
 946         int                     type)
 947 {
 948         acpi_status             status;
 949         struct acpi_ec          *ec;
 950
 951         ACPI_FUNCTION_TRACE("acpi_ec_stop");
 952
 953         if (!device)
 954                 return_VALUE(-EINVAL);
 955
 956         ec = acpi_driver_data(device);
 957
 958         status = acpi_remove_address_space_handler(ec->handle,
 959                 ACPI_ADR_SPACE_EC, &acpi_ec_space_handler);
 960         if (ACPI_FAILURE(status))
 961                 return_VALUE(-ENODEV);
 962
 963         status = acpi_remove_gpe_handler(NULL, ec->gpe_bit, &acpi_ec_gpe_handler);
 964         if (ACPI_FAILURE(status))
 965                 return_VALUE(-ENODEV);
 966
 967         return_VALUE(0);
 968 }
 969
 970 static acpi_status __init
 971 acpi_fake_ecdt_callback (
 972         acpi_handle     handle,
 973         u32             Level,
 974         void            *context,
 975         void            **retval)
 976 {
 977         acpi_status     status;
 978
 979         status = acpi_walk_resources(handle, METHOD_NAME__CRS,
 980                 acpi_ec_io_ports, ec_ecdt);
 981         if (ACPI_FAILURE(status))
 982                 return status;
 983         ec_ecdt->status_addr = ec_ecdt->command_addr;
 984
 985         ec_ecdt->uid = -1;
 986         acpi_evaluate_integer(handle, "_UID", NULL, &ec_ecdt->uid);
 987
 988         status = acpi_evaluate_integer(handle, "_GPE", NULL, &ec_ecdt->gpe_bit);
 989         if (ACPI_FAILURE(status))
 990                 return status;
 991         ec_ecdt->global_lock = TRUE;
 992         ec_ecdt->handle = handle;
 993
 994         printk(KERN_INFO PREFIX  "GPE=0x%02x, ports=0x%2x, 0x%2x\n",
 995                 (u32) ec_ecdt->gpe_bit, (u32) ec_ecdt->command_addr.address,
 996                 (u32) ec_ecdt->data_addr.address);
 997
 998         return AE_CTRL_TERMINATE;
 999 }
1000
1001 /*
1002  * Some BIOS (such as some from Gateway laptops) access EC region very early
1003  * such as in BAT0._INI or EC._INI before an EC device is found and
1004  * do not provide an ECDT. According to ACPI spec, ECDT isn't mandatorily
1005  * required, but if EC regison is accessed early, it is required.
1006  * The routine tries to workaround the BIOS bug by pre-scan EC device
1007  * It assumes that _CRS, _HID, _GPE, _UID methods of EC don't touch any
1008  * op region (since _REG isn't invoked yet). The assumption is true for
1009  * all systems found.
1010  */
1011 static int __init
1012 acpi_ec_fake_ecdt(void)
1013 {
1014         acpi_status     status;
1015         int             ret = 0;
1016
1017         printk(KERN_INFO PREFIX "Try to make an fake ECDT\n");
1018
1019         ec_ecdt = kmalloc(sizeof(struct acpi_ec), GFP_KERNEL);
1020         if (!ec_ecdt) {
1021                 ret = -ENOMEM;
1022                 goto error;
1023         }
1024         memset(ec_ecdt, 0, sizeof(struct acpi_ec));
1025
1026         status = acpi_get_devices (ACPI_EC_HID,
1027                                 acpi_fake_ecdt_callback,
1028                                 NULL,
1029                                 NULL);
1030         if (ACPI_FAILURE(status)) {
1031                 kfree(ec_ecdt);
1032                 ec_ecdt = NULL;
1033                 ret = -ENODEV;
1034                 goto error;
1035         }
1036         return 0;
1037 error:
1038         printk(KERN_ERR PREFIX "Can't make an fake ECDT\n");
1039         return ret;
1040 }
1041
1042 static int __init
1043 acpi_ec_get_real_ecdt(void)
1044 {
1045         acpi_status             status;
1046         struct acpi_table_ecdt  *ecdt_ptr;
1047
1048         status = acpi_get_firmware_table("ECDT", 1, ACPI_LOGICAL_ADDRESSING,
1049                 (struct acpi_table_header **) &ecdt_ptr);
1050         if (ACPI_FAILURE(status))
1051                 return -ENODEV;
1052
1053         printk(KERN_INFO PREFIX "Found ECDT\n");
1054
1055         /*
1056          * Generate a temporary ec context to use until the namespace is scanned
1057          */
1058         ec_ecdt = kmalloc(sizeof(struct acpi_ec), GFP_KERNEL);
1059         if (!ec_ecdt)
1060                 return -ENOMEM;
1061         memset(ec_ecdt, 0, sizeof(struct acpi_ec));
1062
1063         init_MUTEX(&ec_ecdt->sem);
1064         init_waitqueue_head(&ec_ecdt->wait);
1065         ec_ecdt->command_addr = ecdt_ptr->ec_control;
1066         ec_ecdt->status_addr = ecdt_ptr->ec_control;
1067         ec_ecdt->data_addr = ecdt_ptr->ec_data;
1068         ec_ecdt->gpe_bit = ecdt_ptr->gpe_bit;
1069         /* use the GL just to be safe */
1070         ec_ecdt->global_lock = TRUE;
1071         ec_ecdt->uid = ecdt_ptr->uid;
1072
1073         status = acpi_get_handle(NULL, ecdt_ptr->ec_id, &ec_ecdt->handle);
1074         if (ACPI_FAILURE(status)) {
1075                 goto error;
1076         }
1077
1078         return 0;
1079 error:
1080         printk(KERN_ERR PREFIX "Could not use ECDT\n");
1081         kfree(ec_ecdt);
1082         ec_ecdt = NULL;
1083
1084         return -ENODEV;
1085 }
1086
1087 static int __initdata acpi_fake_ecdt_enabled;
1088 int __init
1089 acpi_ec_ecdt_probe (void)
1090 {
1091         acpi_status             status;
1092         int                     ret;
1093
1094         ret = acpi_ec_get_real_ecdt();
1095         /* Try to make a fake ECDT */
1096         if (ret && acpi_fake_ecdt_enabled) {
1097                 ret = acpi_ec_fake_ecdt();
1098         }
1099
1100         if (ret)
1101                 return 0;
1102
1103         /*
1104          * Install GPE handler
1105          */
1106         status = acpi_install_gpe_handler(NULL, ec_ecdt->gpe_bit,
1107                 ACPI_GPE_EDGE_TRIGGERED, &acpi_ec_gpe_handler,
1108                 ec_ecdt);
1109         if (ACPI_FAILURE(status)) {
1110                 goto error;
1111         }
1112         acpi_set_gpe_type (NULL, ec_ecdt->gpe_bit, ACPI_GPE_TYPE_RUNTIME);
1113         acpi_enable_gpe (NULL, ec_ecdt->gpe_bit, ACPI_NOT_ISR);
1114
1115         status = acpi_install_address_space_handler (ACPI_ROOT_OBJECT,
1116                         ACPI_ADR_SPACE_EC, &acpi_ec_space_handler,
1117                         &acpi_ec_space_setup, ec_ecdt);
1118         if (ACPI_FAILURE(status)) {
1119                 acpi_remove_gpe_handler(NULL, ec_ecdt->gpe_bit,
1120                         &acpi_ec_gpe_handler);
1121                 goto error;
1122         }
1123
1124         return 0;
1125
1126 error:
1127         printk(KERN_ERR PREFIX "Could not use ECDT\n");
1128         kfree(ec_ecdt);
1129         ec_ecdt = NULL;
1130
1131         return -ENODEV;
1132 }
1133
1134
1135 static int __init acpi_ec_init (void)
1136 {
1137         int                     result;
1138
1139         ACPI_FUNCTION_TRACE("acpi_ec_init");
1140
1141         if (acpi_disabled)
1142                 return_VALUE(0);
1143
1144         acpi_ec_dir = proc_mkdir(ACPI_EC_CLASS, acpi_root_dir);
1145         if (!acpi_ec_dir)
1146                 return_VALUE(-ENODEV);
1147
1148         /* Now register the driver for the EC */
1149         result = acpi_bus_register_driver(&acpi_ec_driver);
1150         if (result < 0) {
1151                 remove_proc_entry(ACPI_EC_CLASS, acpi_root_dir);
1152                 return_VALUE(-ENODEV);
1153         }
1154
1155         return_VALUE(result);
1156 }
1157
1158 subsys_initcall(acpi_ec_init);
1159
1160 /* EC driver currently not unloadable */
1161 #if 0
1162 static void __exit
1163 acpi_ec_exit (void)
1164 {
1165         ACPI_FUNCTION_TRACE("acpi_ec_exit");
1166
1167         acpi_bus_unregister_driver(&acpi_ec_driver);
1168
1169         remove_proc_entry(ACPI_EC_CLASS, acpi_root_dir);
1170
1171         return_VOID;
1172 }
1173 #endif /* 0 */
1174
1175 static int __init acpi_fake_ecdt_setup(char *str)
1176 {
1177         acpi_fake_ecdt_enabled = 1;
1178         return 0;
1179 }
1180 __setup("acpi_fake_ecdt", acpi_fake_ecdt_setup);