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 #define ACPI_EC_COMPONENT               0x00100000
  43 #define ACPI_EC_CLASS                   "embedded_controller"
  44 #define ACPI_EC_HID                     "PNP0C09"
  45 #define ACPI_EC_DRIVER_NAME             "ACPI Embedded Controller Driver"
  46 #define ACPI_EC_DEVICE_NAME             "Embedded Controller"
  47 #define ACPI_EC_FILE_INFO               "info"
  48 #define ACPI_EC_FLAG_OBF        0x01    /* Output buffer full */
  49 #define ACPI_EC_FLAG_IBF        0x02    /* Input buffer full */
  50 #define ACPI_EC_FLAG_BURST      0x10    /* burst mode */
  51 #define ACPI_EC_FLAG_SCI        0x20    /* EC-SCI occurred */
  52 #define ACPI_EC_EVENT_OBF       0x01    /* Output buffer full */
  53 #define ACPI_EC_EVENT_IBE       0x02    /* Input buffer empty */
  54 #define ACPI_EC_DELAY           50      /* Wait 50ms max. during EC ops */
  55 #define ACPI_EC_UDELAY_GLK      1000    /* Wait 1ms max. to get global lock */
  56 #define ACPI_EC_UDELAY         100      /* Poll @ 100us increments */
  57 #define ACPI_EC_UDELAY_COUNT   1000     /* Wait 10ms max. during EC ops */
  58 #define ACPI_EC_COMMAND_READ    0x80
  59 #define ACPI_EC_COMMAND_WRITE   0x81
  60 #define ACPI_EC_BURST_ENABLE    0x82
  61 #define ACPI_EC_BURST_DISABLE   0x83
  62 #define ACPI_EC_COMMAND_QUERY   0x84
  63 #define EC_POLLING              0xFF
  64 #define EC_BURST                0x00
  65 static int acpi_ec_remove(struct acpi_device *device, int type);
  66 static int acpi_ec_start(struct acpi_device *device);
  67 static int acpi_ec_stop(struct acpi_device *device, int type);
  68 static int acpi_ec_burst_add(struct acpi_device *device);
  69 static int acpi_ec_polling_add(struct acpi_device *device);
  70
  71 static struct acpi_driver acpi_ec_driver = {
  72         .name = ACPI_EC_DRIVER_NAME,
  73         .class = ACPI_EC_CLASS,
  74         .ids = ACPI_EC_HID,
  75         .ops = {
  76                 .add = acpi_ec_polling_add,
  77                 .remove = acpi_ec_remove,
  78                 .start = acpi_ec_start,
  79                 .stop = acpi_ec_stop,
  80                 },
  81 };
  82 union acpi_ec {
  83         struct {
  84                 u32 mode;
  85                 acpi_handle handle;
  86                 unsigned long uid;
  87                 unsigned long gpe_bit;
  88                 struct acpi_generic_address status_addr;
  89                 struct acpi_generic_address command_addr;
  90                 struct acpi_generic_address data_addr;
  91                 unsigned long global_lock;
  92         } common;
  93
  94         struct {
  95                 u32 mode;
  96                 acpi_handle handle;
  97                 unsigned long uid;
  98                 unsigned long gpe_bit;
  99                 struct acpi_generic_address status_addr;
 100                 struct acpi_generic_address command_addr;
 101                 struct acpi_generic_address data_addr;
 102                 unsigned long global_lock;
 103                 unsigned int expect_event;
 104                 atomic_t leaving_burst; /* 0 : No, 1 : Yes, 2: abort */
 105                 atomic_t pending_gpe;
 106                 struct semaphore sem;
 107                 wait_queue_head_t wait;
 108         } burst;
 109
 110         struct {
 111                 u32 mode;
 112                 acpi_handle handle;
 113                 unsigned long uid;
 114                 unsigned long gpe_bit;
 115                 struct acpi_generic_address status_addr;
 116                 struct acpi_generic_address command_addr;
 117                 struct acpi_generic_address data_addr;
 118                 unsigned long global_lock;
 119                 spinlock_t lock;
 120         } polling;
 121 };
 122
 123 static int acpi_ec_polling_wait(union acpi_ec *ec, u8 event);
 124 static int acpi_ec_burst_wait(union acpi_ec *ec, unsigned int event);
 125 static int acpi_ec_polling_read(union acpi_ec *ec, u8 address, u32 * data);
 126 static int acpi_ec_burst_read(union acpi_ec *ec, u8 address, u32 * data);
 127 static int acpi_ec_polling_write(union acpi_ec *ec, u8 address, u8 data);
 128 static int acpi_ec_burst_write(union acpi_ec *ec, u8 address, u8 data);
 129 static int acpi_ec_polling_query(union acpi_ec *ec, u32 * data);
 130 static int acpi_ec_burst_query(union acpi_ec *ec, u32 * data);
 131 static void acpi_ec_gpe_polling_query(void *ec_cxt);
 132 static void acpi_ec_gpe_burst_query(void *ec_cxt);
 133 static u32 acpi_ec_gpe_polling_handler(void *data);
 134 static u32 acpi_ec_gpe_burst_handler(void *data);
 135 static acpi_status __init
 136 acpi_fake_ecdt_polling_callback(acpi_handle handle,
 137                                 u32 Level, void *context, void **retval);
 138
 139 static acpi_status __init
 140 acpi_fake_ecdt_burst_callback(acpi_handle handle,
 141                               u32 Level, void *context, void **retval);
 142
 143 static int __init acpi_ec_polling_get_real_ecdt(void);
 144 static int __init acpi_ec_burst_get_real_ecdt(void);
 145 /* If we find an EC via the ECDT, we need to keep a ptr to its context */
 146 static union acpi_ec *ec_ecdt;
 147
 148 /* External interfaces use first EC only, so remember */
 149 static struct acpi_device *first_ec;
 150 static int acpi_ec_polling_mode = EC_POLLING;
 151
 152 /* --------------------------------------------------------------------------
 153                              Transaction Management
 154    -------------------------------------------------------------------------- */
 155
 156 static inline u32 acpi_ec_read_status(union acpi_ec *ec)
 157 {
 158         u32 status = 0;
 159
 160         acpi_hw_low_level_read(8, &status, &ec->common.status_addr);
 161         return status;
 162 }
 163
 164 static int acpi_ec_wait(union acpi_ec *ec, u8 event)
 165 {
 166         if (acpi_ec_polling_mode)
 167                 return acpi_ec_polling_wait(ec, event);
 168         else
 169                 return acpi_ec_burst_wait(ec, event);
 170 }
 171
 172 static int acpi_ec_polling_wait(union acpi_ec *ec, u8 event)
 173 {
 174         u32 acpi_ec_status = 0;
 175         u32 i = ACPI_EC_UDELAY_COUNT;
 176
 177         if (!ec)
 178                 return -EINVAL;
 179
 180         /* Poll the EC status register waiting for the event to occur. */
 181         switch (event) {
 182         case ACPI_EC_EVENT_OBF:
 183                 do {
 184                         acpi_hw_low_level_read(8, &acpi_ec_status,
 185                                                &ec->common.status_addr);
 186                         if (acpi_ec_status & ACPI_EC_FLAG_OBF)
 187                                 return 0;
 188                         udelay(ACPI_EC_UDELAY);
 189                 } while (--i > 0);
 190                 break;
 191         case ACPI_EC_EVENT_IBE:
 192                 do {
 193                         acpi_hw_low_level_read(8, &acpi_ec_status,
 194                                                &ec->common.status_addr);
 195                         if (!(acpi_ec_status & ACPI_EC_FLAG_IBF))
 196                                 return 0;
 197                         udelay(ACPI_EC_UDELAY);
 198                 } while (--i > 0);
 199                 break;
 200         default:
 201                 return -EINVAL;
 202         }
 203
 204         return -ETIME;
 205 }
 206 static int acpi_ec_burst_wait(union acpi_ec *ec, unsigned int event)
 207 {
 208         int result = 0;
 209
 210         ACPI_FUNCTION_TRACE("acpi_ec_wait");
 211
 212         ec->burst.expect_event = event;
 213         smp_mb();
 214
 215         switch (event) {
 216         case ACPI_EC_EVENT_OBF:
 217                 if (acpi_ec_read_status(ec) & event) {
 218                         ec->burst.expect_event = 0;
 219                         return_VALUE(0);
 220                 }
 221                 break;
 222
 223         case ACPI_EC_EVENT_IBE:
 224                 if (~acpi_ec_read_status(ec) & event) {
 225                         ec->burst.expect_event = 0;
 226                         return_VALUE(0);
 227                 }
 228                 break;
 229         }
 230
 231         result = wait_event_timeout(ec->burst.wait,
 232                                     !ec->burst.expect_event,
 233                                     msecs_to_jiffies(ACPI_EC_DELAY));
 234
 235         ec->burst.expect_event = 0;
 236         smp_mb();
 237
 238         /*
 239          * Verify that the event in question has actually happened by
 240          * querying EC status. Do the check even if operation timed-out
 241          * to make sure that we did not miss interrupt.
 242          */
 243         switch (event) {
 244         case ACPI_EC_EVENT_OBF:
 245                 if (acpi_ec_read_status(ec) & ACPI_EC_FLAG_OBF)
 246                         return_VALUE(0);
 247                 break;
 248
 249         case ACPI_EC_EVENT_IBE:
 250                 if (~acpi_ec_read_status(ec) & ACPI_EC_FLAG_IBF)
 251                         return_VALUE(0);
 252                 break;
 253         }
 254
 255         return_VALUE(-ETIME);
 256 }
 257
 258 static int acpi_ec_enter_burst_mode(union acpi_ec *ec)
 259 {
 260         u32 tmp = 0;
 261         int status = 0;
 262
 263         ACPI_FUNCTION_TRACE("acpi_ec_enter_burst_mode");
 264
 265         status = acpi_ec_read_status(ec);
 266         if (status != -EINVAL && !(status & ACPI_EC_FLAG_BURST)) {
 267                 status = acpi_ec_wait(ec, ACPI_EC_EVENT_IBE);
 268                 if (status)
 269                         goto end;
 270                 acpi_hw_low_level_write(8, ACPI_EC_BURST_ENABLE,
 271                                         &ec->common.command_addr);
 272                 status = acpi_ec_wait(ec, ACPI_EC_EVENT_OBF);
 273                 if (status)
 274                         return_VALUE(-EINVAL);
 275                 acpi_hw_low_level_read(8, &tmp, &ec->common.data_addr);
 276                 if (tmp != 0x90) {      /* Burst ACK byte */
 277                         return_VALUE(-EINVAL);
 278                 }
 279         }
 280
 281         atomic_set(&ec->burst.leaving_burst, 0);
 282         return_VALUE(0);
 283       end:
 284         printk("Error in acpi_ec_wait\n");
 285         return_VALUE(-1);
 286 }
 287
 288 static int acpi_ec_leave_burst_mode(union acpi_ec *ec)
 289 {
 290
 291         ACPI_FUNCTION_TRACE("acpi_ec_leave_burst_mode");
 292
 293         atomic_set(&ec->burst.leaving_burst, 1);
 294         return_VALUE(0);
 295 }
 296
 297 static int acpi_ec_read(union acpi_ec *ec, u8 address, u32 * data)
 298 {
 299         if (acpi_ec_polling_mode)
 300                 return acpi_ec_polling_read(ec, address, data);
 301         else
 302                 return acpi_ec_burst_read(ec, address, data);
 303 }
 304 static int acpi_ec_write(union acpi_ec *ec, u8 address, u8 data)
 305 {
 306         if (acpi_ec_polling_mode)
 307                 return acpi_ec_polling_write(ec, address, data);
 308         else
 309                 return acpi_ec_burst_write(ec, address, data);
 310 }
 311 static int acpi_ec_polling_read(union acpi_ec *ec, u8 address, u32 * data)
 312 {
 313         acpi_status status = AE_OK;
 314         int result = 0;
 315         unsigned long flags = 0;
 316         u32 glk = 0;
 317
 318         ACPI_FUNCTION_TRACE("acpi_ec_read");
 319
 320         if (!ec || !data)
 321                 return_VALUE(-EINVAL);
 322
 323         *data = 0;
 324
 325         if (ec->common.global_lock) {
 326                 status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk);
 327                 if (ACPI_FAILURE(status))
 328                         return_VALUE(-ENODEV);
 329         }
 330
 331         spin_lock_irqsave(&ec->polling.lock, flags);
 332
 333         acpi_hw_low_level_write(8, ACPI_EC_COMMAND_READ,
 334                                 &ec->common.command_addr);
 335         result = acpi_ec_wait(ec, ACPI_EC_EVENT_IBE);
 336         if (result)
 337                 goto end;
 338
 339         acpi_hw_low_level_write(8, address, &ec->common.data_addr);
 340         result = acpi_ec_wait(ec, ACPI_EC_EVENT_OBF);
 341         if (result)
 342                 goto end;
 343
 344         acpi_hw_low_level_read(8, data, &ec->common.data_addr);
 345
 346         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Read [%02x] from address [%02x]\n",
 347                           *data, address));
 348
 349       end:
 350         spin_unlock_irqrestore(&ec->polling.lock, flags);
 351
 352         if (ec->common.global_lock)
 353                 acpi_release_global_lock(glk);
 354
 355         return_VALUE(result);
 356 }
 357
 358 static int acpi_ec_polling_write(union acpi_ec *ec, u8 address, u8 data)
 359 {
 360         int result = 0;
 361         acpi_status status = AE_OK;
 362         unsigned long flags = 0;
 363         u32 glk = 0;
 364
 365         ACPI_FUNCTION_TRACE("acpi_ec_write");
 366
 367         if (!ec)
 368                 return_VALUE(-EINVAL);
 369
 370         if (ec->common.global_lock) {
 371                 status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk);
 372                 if (ACPI_FAILURE(status))
 373                         return_VALUE(-ENODEV);
 374         }
 375
 376         spin_lock_irqsave(&ec->polling.lock, flags);
 377
 378         acpi_hw_low_level_write(8, ACPI_EC_COMMAND_WRITE,
 379                                 &ec->common.command_addr);
 380         result = acpi_ec_wait(ec, ACPI_EC_EVENT_IBE);
 381         if (result)
 382                 goto end;
 383
 384         acpi_hw_low_level_write(8, address, &ec->common.data_addr);
 385         result = acpi_ec_wait(ec, ACPI_EC_EVENT_IBE);
 386         if (result)
 387                 goto end;
 388
 389         acpi_hw_low_level_write(8, data, &ec->common.data_addr);
 390         result = acpi_ec_wait(ec, ACPI_EC_EVENT_IBE);
 391         if (result)
 392                 goto end;
 393
 394         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Wrote [%02x] to address [%02x]\n",
 395                           data, address));
 396
 397       end:
 398         spin_unlock_irqrestore(&ec->polling.lock, flags);
 399
 400         if (ec->common.global_lock)
 401                 acpi_release_global_lock(glk);
 402
 403         return_VALUE(result);
 404 }
 405
 406 static int acpi_ec_burst_read(union acpi_ec *ec, u8 address, u32 * data)
 407 {
 408         int status = 0;
 409         u32 glk;
 410
 411         ACPI_FUNCTION_TRACE("acpi_ec_read");
 412
 413         if (!ec || !data)
 414                 return_VALUE(-EINVAL);
 415
 416         *data = 0;
 417
 418         if (ec->common.global_lock) {
 419                 status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk);
 420                 if (ACPI_FAILURE(status))
 421                         return_VALUE(-ENODEV);
 422         }
 423
 424         WARN_ON(in_interrupt());
 425         down(&ec->burst.sem);
 426
 427         acpi_ec_enter_burst_mode(ec);
 428         status = acpi_ec_wait(ec, ACPI_EC_EVENT_IBE);
 429         if (status) {
 430                 printk("read EC, IB not empty\n");
 431                 goto end;
 432         }
 433         acpi_hw_low_level_write(8, ACPI_EC_COMMAND_READ,
 434                                 &ec->common.command_addr);
 435         status = acpi_ec_wait(ec, ACPI_EC_EVENT_IBE);
 436         if (status) {
 437                 printk("read EC, IB not empty\n");
 438         }
 439
 440         acpi_hw_low_level_write(8, address, &ec->common.data_addr);
 441         status = acpi_ec_wait(ec, ACPI_EC_EVENT_OBF);
 442         if (status) {
 443                 printk("read EC, OB not full\n");
 444                 goto end;
 445         }
 446         acpi_hw_low_level_read(8, data, &ec->common.data_addr);
 447         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Read [%02x] from address [%02x]\n",
 448                           *data, address));
 449
 450       end:
 451         acpi_ec_leave_burst_mode(ec);
 452         up(&ec->burst.sem);
 453
 454         if (ec->common.global_lock)
 455                 acpi_release_global_lock(glk);
 456
 457         return_VALUE(status);
 458 }
 459
 460 static int acpi_ec_burst_write(union acpi_ec *ec, u8 address, u8 data)
 461 {
 462         int status = 0;
 463         u32 glk;
 464
 465         ACPI_FUNCTION_TRACE("acpi_ec_write");
 466
 467         if (!ec)
 468                 return_VALUE(-EINVAL);
 469
 470         if (ec->common.global_lock) {
 471                 status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk);
 472                 if (ACPI_FAILURE(status))
 473                         return_VALUE(-ENODEV);
 474         }
 475
 476         WARN_ON(in_interrupt());
 477         down(&ec->burst.sem);
 478
 479         acpi_ec_enter_burst_mode(ec);
 480
 481         status = acpi_ec_wait(ec, ACPI_EC_EVENT_IBE);
 482         if (status) {
 483                 printk("write EC, IB not empty\n");
 484         }
 485         acpi_hw_low_level_write(8, ACPI_EC_COMMAND_WRITE,
 486                                 &ec->common.command_addr);
 487         status = acpi_ec_wait(ec, ACPI_EC_EVENT_IBE);
 488         if (status) {
 489                 printk("write EC, IB not empty\n");
 490         }
 491
 492         acpi_hw_low_level_write(8, address, &ec->common.data_addr);
 493         status = acpi_ec_wait(ec, ACPI_EC_EVENT_IBE);
 494         if (status) {
 495                 printk("write EC, IB not empty\n");
 496         }
 497
 498         acpi_hw_low_level_write(8, data, &ec->common.data_addr);
 499
 500         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Wrote [%02x] to address [%02x]\n",
 501                           data, address));
 502
 503         acpi_ec_leave_burst_mode(ec);
 504         up(&ec->burst.sem);
 505
 506         if (ec->common.global_lock)
 507                 acpi_release_global_lock(glk);
 508
 509         return_VALUE(status);
 510 }
 511
 512 /*
 513  * Externally callable EC access functions. For now, assume 1 EC only
 514  */
 515 int ec_read(u8 addr, u8 * val)
 516 {
 517         union acpi_ec *ec;
 518         int err;
 519         u32 temp_data;
 520
 521         if (!first_ec)
 522                 return -ENODEV;
 523
 524         ec = acpi_driver_data(first_ec);
 525
 526         err = acpi_ec_read(ec, addr, &temp_data);
 527
 528         if (!err) {
 529                 *val = temp_data;
 530                 return 0;
 531         } else
 532                 return err;
 533 }
 534
 535 EXPORT_SYMBOL(ec_read);
 536
 537 int ec_write(u8 addr, u8 val)
 538 {
 539         union acpi_ec *ec;
 540         int err;
 541
 542         if (!first_ec)
 543                 return -ENODEV;
 544
 545         ec = acpi_driver_data(first_ec);
 546
 547         err = acpi_ec_write(ec, addr, val);
 548
 549         return err;
 550 }
 551
 552 EXPORT_SYMBOL(ec_write);
 553
 554 static int acpi_ec_query(union acpi_ec *ec, u32 * data)
 555 {
 556         if (acpi_ec_polling_mode)
 557                 return acpi_ec_polling_query(ec, data);
 558         else
 559                 return acpi_ec_burst_query(ec, data);
 560 }
 561 static int acpi_ec_polling_query(union acpi_ec *ec, u32 * data)
 562 {
 563         int result = 0;
 564         acpi_status status = AE_OK;
 565         unsigned long flags = 0;
 566         u32 glk = 0;
 567
 568         ACPI_FUNCTION_TRACE("acpi_ec_query");
 569
 570         if (!ec || !data)
 571                 return_VALUE(-EINVAL);
 572
 573         *data = 0;
 574
 575         if (ec->common.global_lock) {
 576                 status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk);
 577                 if (ACPI_FAILURE(status))
 578                         return_VALUE(-ENODEV);
 579         }
 580
 581         /*
 582          * Query the EC to find out which _Qxx method we need to evaluate.
 583          * Note that successful completion of the query causes the ACPI_EC_SCI
 584          * bit to be cleared (and thus clearing the interrupt source).
 585          */
 586         spin_lock_irqsave(&ec->polling.lock, flags);
 587
 588         acpi_hw_low_level_write(8, ACPI_EC_COMMAND_QUERY,
 589                                 &ec->common.command_addr);
 590         result = acpi_ec_wait(ec, ACPI_EC_EVENT_OBF);
 591         if (result)
 592                 goto end;
 593
 594         acpi_hw_low_level_read(8, data, &ec->common.data_addr);
 595         if (!*data)
 596                 result = -ENODATA;
 597
 598       end:
 599         spin_unlock_irqrestore(&ec->polling.lock, flags);
 600
 601         if (ec->common.global_lock)
 602                 acpi_release_global_lock(glk);
 603
 604         return_VALUE(result);
 605 }
 606 static int acpi_ec_burst_query(union acpi_ec *ec, u32 * data)
 607 {
 608         int status = 0;
 609         u32 glk;
 610
 611         ACPI_FUNCTION_TRACE("acpi_ec_query");
 612
 613         if (!ec || !data)
 614                 return_VALUE(-EINVAL);
 615         *data = 0;
 616
 617         if (ec->common.global_lock) {
 618                 status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk);
 619                 if (ACPI_FAILURE(status))
 620                         return_VALUE(-ENODEV);
 621         }
 622
 623         down(&ec->burst.sem);
 624
 625         status = acpi_ec_wait(ec, ACPI_EC_EVENT_IBE);
 626         if (status) {
 627                 printk("query EC, IB not empty\n");
 628                 goto end;
 629         }
 630         /*
 631          * Query the EC to find out which _Qxx method we need to evaluate.
 632          * Note that successful completion of the query causes the ACPI_EC_SCI
 633          * bit to be cleared (and thus clearing the interrupt source).
 634          */
 635         acpi_hw_low_level_write(8, ACPI_EC_COMMAND_QUERY,
 636                                 &ec->common.command_addr);
 637         status = acpi_ec_wait(ec, ACPI_EC_EVENT_OBF);
 638         if (status) {
 639                 printk("query EC, OB not full\n");
 640                 goto end;
 641         }
 642
 643         acpi_hw_low_level_read(8, data, &ec->common.data_addr);
 644         if (!*data)
 645                 status = -ENODATA;
 646
 647       end:
 648         up(&ec->burst.sem);
 649
 650         if (ec->common.global_lock)
 651                 acpi_release_global_lock(glk);
 652
 653         return_VALUE(status);
 654 }
 655
 656 /* --------------------------------------------------------------------------
 657                                 Event Management
 658    -------------------------------------------------------------------------- */
 659
 660 union acpi_ec_query_data {
 661         acpi_handle handle;
 662         u8 data;
 663 };
 664
 665 static void acpi_ec_gpe_query(void *ec_cxt)
 666 {
 667         if (acpi_ec_polling_mode)
 668                 acpi_ec_gpe_polling_query(ec_cxt);
 669         else
 670                 acpi_ec_gpe_burst_query(ec_cxt);
 671 }
 672
 673 static void acpi_ec_gpe_polling_query(void *ec_cxt)
 674 {
 675         union acpi_ec *ec = (union acpi_ec *)ec_cxt;
 676         u32 value = 0;
 677         unsigned long flags = 0;
 678         static char object_name[5] = { '_', 'Q', '0', '0', '\0' };
 679         const char hex[] = { '0', '1', '2', '3', '4', '5', '6', '7',
 680                 '8', '9', 'A', 'B', 'C', 'D', 'E', 'F'
 681         };
 682
 683         ACPI_FUNCTION_TRACE("acpi_ec_gpe_query");
 684
 685         if (!ec_cxt)
 686                 goto end;
 687
 688         spin_lock_irqsave(&ec->polling.lock, flags);
 689         acpi_hw_low_level_read(8, &value, &ec->common.command_addr);
 690         spin_unlock_irqrestore(&ec->polling.lock, flags);
 691
 692         /* TBD: Implement asynch events!
 693          * NOTE: All we care about are EC-SCI's.  Other EC events are
 694          * handled via polling (yuck!).  This is because some systems
 695          * treat EC-SCIs as level (versus EDGE!) triggered, preventing
 696          *  a purely interrupt-driven approach (grumble, grumble).
 697          */
 698         if (!(value & ACPI_EC_FLAG_SCI))
 699                 goto end;
 700
 701         if (acpi_ec_query(ec, &value))
 702                 goto end;
 703
 704         object_name[2] = hex[((value >> 4) & 0x0F)];
 705         object_name[3] = hex[(value & 0x0F)];
 706
 707         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Evaluating %s\n", object_name));
 708
 709         acpi_evaluate_object(ec->common.handle, object_name, NULL, NULL);
 710
 711       end:
 712         acpi_enable_gpe(NULL, ec->common.gpe_bit, ACPI_NOT_ISR);
 713 }
 714 static void acpi_ec_gpe_burst_query(void *ec_cxt)
 715 {
 716         union acpi_ec *ec = (union acpi_ec *)ec_cxt;
 717         u32 value;
 718         int result = -ENODATA;
 719         static char object_name[5] = { '_', 'Q', '0', '0', '\0' };
 720         const char hex[] = { '0', '1', '2', '3', '4', '5', '6', '7',
 721                 '8', '9', 'A', 'B', 'C', 'D', 'E', 'F'
 722         };
 723
 724         ACPI_FUNCTION_TRACE("acpi_ec_gpe_query");
 725
 726         if (acpi_ec_read_status(ec) & ACPI_EC_FLAG_SCI)
 727                 result = acpi_ec_query(ec, &value);
 728
 729         if (result)
 730                 goto end;
 731
 732         object_name[2] = hex[((value >> 4) & 0x0F)];
 733         object_name[3] = hex[(value & 0x0F)];
 734
 735         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Evaluating %s\n", object_name));
 736
 737         acpi_evaluate_object(ec->common.handle, object_name, NULL, NULL);
 738       end:
 739         atomic_dec(&ec->burst.pending_gpe);
 740         return;
 741 }
 742
 743 static u32 acpi_ec_gpe_handler(void *data)
 744 {
 745         if (acpi_ec_polling_mode)
 746                 return acpi_ec_gpe_polling_handler(data);
 747         else
 748                 return acpi_ec_gpe_burst_handler(data);
 749 }
 750 static u32 acpi_ec_gpe_polling_handler(void *data)
 751 {
 752         acpi_status status = AE_OK;
 753         union acpi_ec *ec = (union acpi_ec *)data;
 754
 755         if (!ec)
 756                 return ACPI_INTERRUPT_NOT_HANDLED;
 757
 758         acpi_disable_gpe(NULL, ec->common.gpe_bit, ACPI_ISR);
 759
 760         status = acpi_os_queue_for_execution(OSD_PRIORITY_GPE,
 761                                              acpi_ec_gpe_query, ec);
 762
 763         if (status == AE_OK)
 764                 return ACPI_INTERRUPT_HANDLED;
 765         else
 766                 return ACPI_INTERRUPT_NOT_HANDLED;
 767 }
 768 static u32 acpi_ec_gpe_burst_handler(void *data)
 769 {
 770         acpi_status status = AE_OK;
 771         u32 value;
 772         union acpi_ec *ec = (union acpi_ec *)data;
 773
 774         if (!ec)
 775                 return ACPI_INTERRUPT_NOT_HANDLED;
 776
 777         acpi_clear_gpe(NULL, ec->common.gpe_bit, ACPI_ISR);
 778         value = acpi_ec_read_status(ec);
 779
 780         switch (ec->burst.expect_event) {
 781         case ACPI_EC_EVENT_OBF:
 782                 if (!(value & ACPI_EC_FLAG_OBF))
 783                         break;
 784         case ACPI_EC_EVENT_IBE:
 785                 if ((value & ACPI_EC_FLAG_IBF))
 786                         break;
 787                 ec->burst.expect_event = 0;
 788                 wake_up(&ec->burst.wait);
 789                 return ACPI_INTERRUPT_HANDLED;
 790         default:
 791                 break;
 792         }
 793
 794         if (value & ACPI_EC_FLAG_SCI) {
 795                 atomic_add(1, &ec->burst.pending_gpe);
 796                 status = acpi_os_queue_for_execution(OSD_PRIORITY_GPE,
 797                                                      acpi_ec_gpe_query, ec);
 798                 return status == AE_OK ?
 799                     ACPI_INTERRUPT_HANDLED : ACPI_INTERRUPT_NOT_HANDLED;
 800         }
 801         acpi_enable_gpe(NULL, ec->common.gpe_bit, ACPI_ISR);
 802         return status == AE_OK ?
 803             ACPI_INTERRUPT_HANDLED : ACPI_INTERRUPT_NOT_HANDLED;
 804 }
 805
 806 /* --------------------------------------------------------------------------
 807                              Address Space Management
 808    -------------------------------------------------------------------------- */
 809
 810 static acpi_status
 811 acpi_ec_space_setup(acpi_handle region_handle,
 812                     u32 function, void *handler_context, void **return_context)
 813 {
 814         /*
 815          * The EC object is in the handler context and is needed
 816          * when calling the acpi_ec_space_handler.
 817          */
 818         *return_context = (function != ACPI_REGION_DEACTIVATE) ?
 819             handler_context : NULL;
 820
 821         return AE_OK;
 822 }
 823
 824 static acpi_status
 825 acpi_ec_space_handler(u32 function,
 826                       acpi_physical_address address,
 827                       u32 bit_width,
 828                       acpi_integer * value,
 829                       void *handler_context, void *region_context)
 830 {
 831         int result = 0;
 832         union acpi_ec *ec = NULL;
 833         u64 temp = *value;
 834         acpi_integer f_v = 0;
 835         int i = 0;
 836
 837         ACPI_FUNCTION_TRACE("acpi_ec_space_handler");
 838
 839         if ((address > 0xFF) || !value || !handler_context)
 840                 return_VALUE(AE_BAD_PARAMETER);
 841
 842         if (bit_width != 8 && acpi_strict) {
 843                 printk(KERN_WARNING PREFIX
 844                        "acpi_ec_space_handler: bit_width should be 8\n");
 845                 return_VALUE(AE_BAD_PARAMETER);
 846         }
 847
 848         ec = (union acpi_ec *)handler_context;
 849
 850       next_byte:
 851         switch (function) {
 852         case ACPI_READ:
 853                 temp = 0;
 854                 result = acpi_ec_read(ec, (u8) address, (u32 *) & temp);
 855                 break;
 856         case ACPI_WRITE:
 857                 result = acpi_ec_write(ec, (u8) address, (u8) temp);
 858                 break;
 859         default:
 860                 result = -EINVAL;
 861                 goto out;
 862                 break;
 863         }
 864
 865         bit_width -= 8;
 866         if (bit_width) {
 867                 if (function == ACPI_READ)
 868                         f_v |= temp << 8 * i;
 869                 if (function == ACPI_WRITE)
 870                         temp >>= 8;
 871                 i++;
 872                 address++;
 873                 goto next_byte;
 874         }
 875
 876         if (function == ACPI_READ) {
 877                 f_v |= temp << 8 * i;
 878                 *value = f_v;
 879         }
 880
 881       out:
 882         switch (result) {
 883         case -EINVAL:
 884                 return_VALUE(AE_BAD_PARAMETER);
 885                 break;
 886         case -ENODEV:
 887                 return_VALUE(AE_NOT_FOUND);
 888                 break;
 889         case -ETIME:
 890                 return_VALUE(AE_TIME);
 891                 break;
 892         default:
 893                 return_VALUE(AE_OK);
 894         }
 895 }
 896
 897 /* --------------------------------------------------------------------------
 898                               FS Interface (/proc)
 899    -------------------------------------------------------------------------- */
 900
 901 static struct proc_dir_entry *acpi_ec_dir;
 902
 903 static int acpi_ec_read_info(struct seq_file *seq, void *offset)
 904 {
 905         union acpi_ec *ec = (union acpi_ec *)seq->private;
 906
 907         ACPI_FUNCTION_TRACE("acpi_ec_read_info");
 908
 909         if (!ec)
 910                 goto end;
 911
 912         seq_printf(seq, "gpe bit:                 0x%02x\n",
 913                    (u32) ec->common.gpe_bit);
 914         seq_printf(seq, "ports:                   0x%02x, 0x%02x\n",
 915                    (u32) ec->common.status_addr.address,
 916                    (u32) ec->common.data_addr.address);
 917         seq_printf(seq, "use global lock:         %s\n",
 918                    ec->common.global_lock ? "yes" : "no");
 919         acpi_enable_gpe(NULL, ec->common.gpe_bit, ACPI_NOT_ISR);
 920
 921       end:
 922         return_VALUE(0);
 923 }
 924
 925 static int acpi_ec_info_open_fs(struct inode *inode, struct file *file)
 926 {
 927         return single_open(file, acpi_ec_read_info, PDE(inode)->data);
 928 }
 929
 930 static struct file_operations acpi_ec_info_ops = {
 931         .open = acpi_ec_info_open_fs,
 932         .read = seq_read,
 933         .llseek = seq_lseek,
 934         .release = single_release,
 935         .owner = THIS_MODULE,
 936 };
 937
 938 static int acpi_ec_add_fs(struct acpi_device *device)
 939 {
 940         struct proc_dir_entry *entry = NULL;
 941
 942         ACPI_FUNCTION_TRACE("acpi_ec_add_fs");
 943
 944         if (!acpi_device_dir(device)) {
 945                 acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device),
 946                                                      acpi_ec_dir);
 947                 if (!acpi_device_dir(device))
 948                         return_VALUE(-ENODEV);
 949         }
 950
 951         entry = create_proc_entry(ACPI_EC_FILE_INFO, S_IRUGO,
 952                                   acpi_device_dir(device));
 953         if (!entry)
 954                 ACPI_DEBUG_PRINT((ACPI_DB_WARN,
 955                                   "Unable to create '%s' fs entry\n",
 956                                   ACPI_EC_FILE_INFO));
 957         else {
 958                 entry->proc_fops = &acpi_ec_info_ops;
 959                 entry->data = acpi_driver_data(device);
 960                 entry->owner = THIS_MODULE;
 961         }
 962
 963         return_VALUE(0);
 964 }
 965
 966 static int acpi_ec_remove_fs(struct acpi_device *device)
 967 {
 968         ACPI_FUNCTION_TRACE("acpi_ec_remove_fs");
 969
 970         if (acpi_device_dir(device)) {
 971                 remove_proc_entry(ACPI_EC_FILE_INFO, acpi_device_dir(device));
 972                 remove_proc_entry(acpi_device_bid(device), acpi_ec_dir);
 973                 acpi_device_dir(device) = NULL;
 974         }
 975
 976         return_VALUE(0);
 977 }
 978
 979 /* --------------------------------------------------------------------------
 980                                Driver Interface
 981    -------------------------------------------------------------------------- */
 982
 983 static int acpi_ec_polling_add(struct acpi_device *device)
 984 {
 985         int result = 0;
 986         acpi_status status = AE_OK;
 987         union acpi_ec *ec = NULL;
 988         unsigned long uid;
 989
 990         ACPI_FUNCTION_TRACE("acpi_ec_add");
 991
 992         if (!device)
 993                 return_VALUE(-EINVAL);
 994
 995         ec = kmalloc(sizeof(union acpi_ec), GFP_KERNEL);
 996         if (!ec)
 997                 return_VALUE(-ENOMEM);
 998         memset(ec, 0, sizeof(union acpi_ec));
 999
1000         ec->common.handle = device->handle;
1001         ec->common.uid = -1;
1002         spin_lock_init(&ec->polling.lock);
1003         strcpy(acpi_device_name(device), ACPI_EC_DEVICE_NAME);
1004         strcpy(acpi_device_class(device), ACPI_EC_CLASS);
1005         acpi_driver_data(device) = ec;
1006
1007         /* Use the global lock for all EC transactions? */
1008         acpi_evaluate_integer(ec->common.handle, "_GLK", NULL,
1009                               &ec->common.global_lock);
1010
1011         /* If our UID matches the UID for the ECDT-enumerated EC,
1012            we now have the *real* EC info, so kill the makeshift one. */
1013         acpi_evaluate_integer(ec->common.handle, "_UID", NULL, &uid);
1014         if (ec_ecdt && ec_ecdt->common.uid == uid) {
1015                 acpi_remove_address_space_handler(ACPI_ROOT_OBJECT,
1016                                                   ACPI_ADR_SPACE_EC,
1017                                                   &acpi_ec_space_handler);
1018
1019                 acpi_remove_gpe_handler(NULL, ec_ecdt->common.gpe_bit,
1020                                         &acpi_ec_gpe_handler);
1021
1022                 kfree(ec_ecdt);
1023         }
1024
1025         /* Get GPE bit assignment (EC events). */
1026         /* TODO: Add support for _GPE returning a package */
1027         status =
1028             acpi_evaluate_integer(ec->common.handle, "_GPE", NULL,
1029                                   &ec->common.gpe_bit);
1030         if (ACPI_FAILURE(status)) {
1031                 ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
1032                                   "Error obtaining GPE bit assignment\n"));
1033                 result = -ENODEV;
1034                 goto end;
1035         }
1036
1037         result = acpi_ec_add_fs(device);
1038         if (result)
1039                 goto end;
1040
1041         printk(KERN_INFO PREFIX "%s [%s] (gpe %d)\n",
1042                acpi_device_name(device), acpi_device_bid(device),
1043                (u32) ec->common.gpe_bit);
1044
1045         if (!first_ec)
1046                 first_ec = device;
1047
1048       end:
1049         if (result)
1050                 kfree(ec);
1051
1052         return_VALUE(result);
1053 }
1054 static int acpi_ec_burst_add(struct acpi_device *device)
1055 {
1056         int result = 0;
1057         acpi_status status = AE_OK;
1058         union acpi_ec *ec = NULL;
1059         unsigned long uid;
1060
1061         ACPI_FUNCTION_TRACE("acpi_ec_add");
1062
1063         if (!device)
1064                 return_VALUE(-EINVAL);
1065
1066         ec = kmalloc(sizeof(union acpi_ec), GFP_KERNEL);
1067         if (!ec)
1068                 return_VALUE(-ENOMEM);
1069         memset(ec, 0, sizeof(union acpi_ec));
1070
1071         ec->common.handle = device->handle;
1072         ec->common.uid = -1;
1073         atomic_set(&ec->burst.pending_gpe, 0);
1074         atomic_set(&ec->burst.leaving_burst, 1);
1075         init_MUTEX(&ec->burst.sem);
1076         init_waitqueue_head(&ec->burst.wait);
1077         strcpy(acpi_device_name(device), ACPI_EC_DEVICE_NAME);
1078         strcpy(acpi_device_class(device), ACPI_EC_CLASS);
1079         acpi_driver_data(device) = ec;
1080
1081         /* Use the global lock for all EC transactions? */
1082         acpi_evaluate_integer(ec->common.handle, "_GLK", NULL,
1083                               &ec->common.global_lock);
1084
1085         /* If our UID matches the UID for the ECDT-enumerated EC,
1086            we now have the *real* EC info, so kill the makeshift one. */
1087         acpi_evaluate_integer(ec->common.handle, "_UID", NULL, &uid);
1088         if (ec_ecdt && ec_ecdt->common.uid == uid) {
1089                 acpi_remove_address_space_handler(ACPI_ROOT_OBJECT,
1090                                                   ACPI_ADR_SPACE_EC,
1091                                                   &acpi_ec_space_handler);
1092
1093                 acpi_remove_gpe_handler(NULL, ec_ecdt->common.gpe_bit,
1094                                         &acpi_ec_gpe_handler);
1095
1096                 kfree(ec_ecdt);
1097         }
1098
1099         /* Get GPE bit assignment (EC events). */
1100         /* TODO: Add support for _GPE returning a package */
1101         status =
1102             acpi_evaluate_integer(ec->common.handle, "_GPE", NULL,
1103                                   &ec->common.gpe_bit);
1104         if (ACPI_FAILURE(status)) {
1105                 ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
1106                                   "Error obtaining GPE bit assignment\n"));
1107                 result = -ENODEV;
1108                 goto end;
1109         }
1110
1111         result = acpi_ec_add_fs(device);
1112         if (result)
1113                 goto end;
1114
1115         printk("burst-mode-ec-10-Aug\n");
1116         printk(KERN_INFO PREFIX "%s [%s] (gpe %d)\n",
1117                acpi_device_name(device), acpi_device_bid(device),
1118                (u32) ec->common.gpe_bit);
1119
1120         if (!first_ec)
1121                 first_ec = device;
1122
1123       end:
1124         if (result)
1125                 kfree(ec);
1126
1127         return_VALUE(result);
1128 }
1129
1130 static int acpi_ec_remove(struct acpi_device *device, int type)
1131 {
1132         union acpi_ec *ec = NULL;
1133
1134         ACPI_FUNCTION_TRACE("acpi_ec_remove");
1135
1136         if (!device)
1137                 return_VALUE(-EINVAL);
1138
1139         ec = acpi_driver_data(device);
1140
1141         acpi_ec_remove_fs(device);
1142
1143         kfree(ec);
1144
1145         return_VALUE(0);
1146 }
1147
1148 static acpi_status
1149 acpi_ec_io_ports(struct acpi_resource *resource, void *context)
1150 {
1151         union acpi_ec *ec = (union acpi_ec *)context;
1152         struct acpi_generic_address *addr;
1153
1154         if (resource->id != ACPI_RSTYPE_IO) {
1155                 return AE_OK;
1156         }
1157
1158         /*
1159          * The first address region returned is the data port, and
1160          * the second address region returned is the status/command
1161          * port.
1162          */
1163         if (ec->common.data_addr.register_bit_width == 0) {
1164                 addr = &ec->common.data_addr;
1165         } else if (ec->common.command_addr.register_bit_width == 0) {
1166                 addr = &ec->common.command_addr;
1167         } else {
1168                 return AE_CTRL_TERMINATE;
1169         }
1170
1171         addr->address_space_id = ACPI_ADR_SPACE_SYSTEM_IO;
1172         addr->register_bit_width = 8;
1173         addr->register_bit_offset = 0;
1174         addr->address = resource->data.io.min_base_address;
1175
1176         return AE_OK;
1177 }
1178
1179 static int acpi_ec_start(struct acpi_device *device)
1180 {
1181         acpi_status status = AE_OK;
1182         union acpi_ec *ec = NULL;
1183
1184         ACPI_FUNCTION_TRACE("acpi_ec_start");
1185
1186         if (!device)
1187                 return_VALUE(-EINVAL);
1188
1189         ec = acpi_driver_data(device);
1190
1191         if (!ec)
1192                 return_VALUE(-EINVAL);
1193
1194         /*
1195          * Get I/O port addresses. Convert to GAS format.
1196          */
1197         status = acpi_walk_resources(ec->common.handle, METHOD_NAME__CRS,
1198                                      acpi_ec_io_ports, ec);
1199         if (ACPI_FAILURE(status)
1200             || ec->common.command_addr.register_bit_width == 0) {
1201                 ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
1202                                   "Error getting I/O port addresses"));
1203                 return_VALUE(-ENODEV);
1204         }
1205
1206         ec->common.status_addr = ec->common.command_addr;
1207
1208         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "gpe=0x%02x, ports=0x%2x,0x%2x\n",
1209                           (u32) ec->common.gpe_bit,
1210                           (u32) ec->common.command_addr.address,
1211                           (u32) ec->common.data_addr.address));
1212
1213         /*
1214          * Install GPE handler
1215          */
1216         status = acpi_install_gpe_handler(NULL, ec->common.gpe_bit,
1217                                           ACPI_GPE_EDGE_TRIGGERED,
1218                                           &acpi_ec_gpe_handler, ec);
1219         if (ACPI_FAILURE(status)) {
1220                 return_VALUE(-ENODEV);
1221         }
1222         acpi_set_gpe_type(NULL, ec->common.gpe_bit, ACPI_GPE_TYPE_RUNTIME);
1223         acpi_enable_gpe(NULL, ec->common.gpe_bit, ACPI_NOT_ISR);
1224
1225         status = acpi_install_address_space_handler(ec->common.handle,
1226                                                     ACPI_ADR_SPACE_EC,
1227                                                     &acpi_ec_space_handler,
1228                                                     &acpi_ec_space_setup, ec);
1229         if (ACPI_FAILURE(status)) {
1230                 acpi_remove_gpe_handler(NULL, ec->common.gpe_bit,
1231                                         &acpi_ec_gpe_handler);
1232                 return_VALUE(-ENODEV);
1233         }
1234
1235         return_VALUE(AE_OK);
1236 }
1237
1238 static int acpi_ec_stop(struct acpi_device *device, int type)
1239 {
1240         acpi_status status = AE_OK;
1241         union acpi_ec *ec = NULL;
1242
1243         ACPI_FUNCTION_TRACE("acpi_ec_stop");
1244
1245         if (!device)
1246                 return_VALUE(-EINVAL);
1247
1248         ec = acpi_driver_data(device);
1249
1250         status = acpi_remove_address_space_handler(ec->common.handle,
1251                                                    ACPI_ADR_SPACE_EC,
1252                                                    &acpi_ec_space_handler);
1253         if (ACPI_FAILURE(status))
1254                 return_VALUE(-ENODEV);
1255
1256         status =
1257             acpi_remove_gpe_handler(NULL, ec->common.gpe_bit,
1258                                     &acpi_ec_gpe_handler);
1259         if (ACPI_FAILURE(status))
1260                 return_VALUE(-ENODEV);
1261
1262         return_VALUE(0);
1263 }
1264
1265 static acpi_status __init
1266 acpi_fake_ecdt_callback(acpi_handle handle,
1267                         u32 Level, void *context, void **retval)
1268 {
1269
1270         if (acpi_ec_polling_mode)
1271                 return acpi_fake_ecdt_polling_callback(handle,
1272                                                        Level, context, retval);
1273         else
1274                 return acpi_fake_ecdt_burst_callback(handle,
1275                                                      Level, context, retval);
1276 }
1277
1278 static acpi_status __init
1279 acpi_fake_ecdt_polling_callback(acpi_handle handle,
1280                                 u32 Level, void *context, void **retval)
1281 {
1282         acpi_status status;
1283
1284         status = acpi_walk_resources(handle, METHOD_NAME__CRS,
1285                                      acpi_ec_io_ports, ec_ecdt);
1286         if (ACPI_FAILURE(status))
1287                 return status;
1288         ec_ecdt->common.status_addr = ec_ecdt->common.command_addr;
1289
1290         ec_ecdt->common.uid = -1;
1291         acpi_evaluate_integer(handle, "_UID", NULL, &ec_ecdt->common.uid);
1292
1293         status =
1294             acpi_evaluate_integer(handle, "_GPE", NULL,
1295                                   &ec_ecdt->common.gpe_bit);
1296         if (ACPI_FAILURE(status))
1297                 return status;
1298         spin_lock_init(&ec_ecdt->polling.lock);
1299         ec_ecdt->common.global_lock = TRUE;
1300         ec_ecdt->common.handle = handle;
1301
1302         printk(KERN_INFO PREFIX "GPE=0x%02x, ports=0x%2x, 0x%2x\n",
1303                (u32) ec_ecdt->common.gpe_bit,
1304                (u32) ec_ecdt->common.command_addr.address,
1305                (u32) ec_ecdt->common.data_addr.address);
1306
1307         return AE_CTRL_TERMINATE;
1308 }
1309
1310 static acpi_status __init
1311 acpi_fake_ecdt_burst_callback(acpi_handle handle,
1312                               u32 Level, void *context, void **retval)
1313 {
1314         acpi_status status;
1315
1316         init_MUTEX(&ec_ecdt->burst.sem);
1317         init_waitqueue_head(&ec_ecdt->burst.wait);
1318         status = acpi_walk_resources(handle, METHOD_NAME__CRS,
1319                                      acpi_ec_io_ports, ec_ecdt);
1320         if (ACPI_FAILURE(status))
1321                 return status;
1322         ec_ecdt->common.status_addr = ec_ecdt->common.command_addr;
1323
1324         ec_ecdt->common.uid = -1;
1325         acpi_evaluate_integer(handle, "_UID", NULL, &ec_ecdt->common.uid);
1326
1327         status =
1328             acpi_evaluate_integer(handle, "_GPE", NULL,
1329                                   &ec_ecdt->common.gpe_bit);
1330         if (ACPI_FAILURE(status))
1331                 return status;
1332         ec_ecdt->common.global_lock = TRUE;
1333         ec_ecdt->common.handle = handle;
1334
1335         printk(KERN_INFO PREFIX "GPE=0x%02x, ports=0x%2x, 0x%2x\n",
1336                (u32) ec_ecdt->common.gpe_bit,
1337                (u32) ec_ecdt->common.command_addr.address,
1338                (u32) ec_ecdt->common.data_addr.address);
1339
1340         return AE_CTRL_TERMINATE;
1341 }
1342
1343 /*
1344  * Some BIOS (such as some from Gateway laptops) access EC region very early
1345  * such as in BAT0._INI or EC._INI before an EC device is found and
1346  * do not provide an ECDT. According to ACPI spec, ECDT isn't mandatorily
1347  * required, but if EC regison is accessed early, it is required.
1348  * The routine tries to workaround the BIOS bug by pre-scan EC device
1349  * It assumes that _CRS, _HID, _GPE, _UID methods of EC don't touch any
1350  * op region (since _REG isn't invoked yet). The assumption is true for
1351  * all systems found.
1352  */
1353 static int __init acpi_ec_fake_ecdt(void)
1354 {
1355         acpi_status status;
1356         int ret = 0;
1357
1358         printk(KERN_INFO PREFIX "Try to make an fake ECDT\n");
1359
1360         ec_ecdt = kmalloc(sizeof(union acpi_ec), GFP_KERNEL);
1361         if (!ec_ecdt) {
1362                 ret = -ENOMEM;
1363                 goto error;
1364         }
1365         memset(ec_ecdt, 0, sizeof(union acpi_ec));
1366
1367         status = acpi_get_devices(ACPI_EC_HID,
1368                                   acpi_fake_ecdt_callback, NULL, NULL);
1369         if (ACPI_FAILURE(status)) {
1370                 kfree(ec_ecdt);
1371                 ec_ecdt = NULL;
1372                 ret = -ENODEV;
1373                 goto error;
1374         }
1375         return 0;
1376       error:
1377         printk(KERN_ERR PREFIX "Can't make an fake ECDT\n");
1378         return ret;
1379 }
1380
1381 static int __init acpi_ec_get_real_ecdt(void)
1382 {
1383         if (acpi_ec_polling_mode)
1384                 return acpi_ec_polling_get_real_ecdt();
1385         else
1386                 return acpi_ec_burst_get_real_ecdt();
1387 }
1388
1389 static int __init acpi_ec_polling_get_real_ecdt(void)
1390 {
1391         acpi_status status;
1392         struct acpi_table_ecdt *ecdt_ptr;
1393
1394         status = acpi_get_firmware_table("ECDT", 1, ACPI_LOGICAL_ADDRESSING,
1395                                          (struct acpi_table_header **)
1396                                          &ecdt_ptr);
1397         if (ACPI_FAILURE(status))
1398                 return -ENODEV;
1399
1400         printk(KERN_INFO PREFIX "Found ECDT\n");
1401
1402         /*
1403          * Generate a temporary ec context to use until the namespace is scanned
1404          */
1405         ec_ecdt = kmalloc(sizeof(union acpi_ec), GFP_KERNEL);
1406         if (!ec_ecdt)
1407                 return -ENOMEM;
1408         memset(ec_ecdt, 0, sizeof(union acpi_ec));
1409
1410         ec_ecdt->common.command_addr = ecdt_ptr->ec_control;
1411         ec_ecdt->common.status_addr = ecdt_ptr->ec_control;
1412         ec_ecdt->common.data_addr = ecdt_ptr->ec_data;
1413         ec_ecdt->common.gpe_bit = ecdt_ptr->gpe_bit;
1414         spin_lock_init(&ec_ecdt->polling.lock);
1415         /* use the GL just to be safe */
1416         ec_ecdt->common.global_lock = TRUE;
1417         ec_ecdt->common.uid = ecdt_ptr->uid;
1418
1419         status =
1420             acpi_get_handle(NULL, ecdt_ptr->ec_id, &ec_ecdt->common.handle);
1421         if (ACPI_FAILURE(status)) {
1422                 goto error;
1423         }
1424
1425         return 0;
1426       error:
1427         printk(KERN_ERR PREFIX "Could not use ECDT\n");
1428         kfree(ec_ecdt);
1429         ec_ecdt = NULL;
1430
1431         return -ENODEV;
1432 }
1433
1434 static int __init acpi_ec_burst_get_real_ecdt(void)
1435 {
1436         acpi_status status;
1437         struct acpi_table_ecdt *ecdt_ptr;
1438
1439         status = acpi_get_firmware_table("ECDT", 1, ACPI_LOGICAL_ADDRESSING,
1440                                          (struct acpi_table_header **)
1441                                          &ecdt_ptr);
1442         if (ACPI_FAILURE(status))
1443                 return -ENODEV;
1444
1445         printk(KERN_INFO PREFIX "Found ECDT\n");
1446
1447         /*
1448          * Generate a temporary ec context to use until the namespace is scanned
1449          */
1450         ec_ecdt = kmalloc(sizeof(union acpi_ec), GFP_KERNEL);
1451         if (!ec_ecdt)
1452                 return -ENOMEM;
1453         memset(ec_ecdt, 0, sizeof(union acpi_ec));
1454
1455         init_MUTEX(&ec_ecdt->burst.sem);
1456         init_waitqueue_head(&ec_ecdt->burst.wait);
1457         ec_ecdt->common.command_addr = ecdt_ptr->ec_control;
1458         ec_ecdt->common.status_addr = ecdt_ptr->ec_control;
1459         ec_ecdt->common.data_addr = ecdt_ptr->ec_data;
1460         ec_ecdt->common.gpe_bit = ecdt_ptr->gpe_bit;
1461         /* use the GL just to be safe */
1462         ec_ecdt->common.global_lock = TRUE;
1463         ec_ecdt->common.uid = ecdt_ptr->uid;
1464
1465         status =
1466             acpi_get_handle(NULL, ecdt_ptr->ec_id, &ec_ecdt->common.handle);
1467         if (ACPI_FAILURE(status)) {
1468                 goto error;
1469         }
1470
1471         return 0;
1472       error:
1473         printk(KERN_ERR PREFIX "Could not use ECDT\n");
1474         kfree(ec_ecdt);
1475         ec_ecdt = NULL;
1476
1477         return -ENODEV;
1478 }
1479
1480 static int __initdata acpi_fake_ecdt_enabled;
1481 int __init acpi_ec_ecdt_probe(void)
1482 {
1483         acpi_status status;
1484         int ret;
1485
1486         ret = acpi_ec_get_real_ecdt();
1487         /* Try to make a fake ECDT */
1488         if (ret && acpi_fake_ecdt_enabled) {
1489                 ret = acpi_ec_fake_ecdt();
1490         }
1491
1492         if (ret)
1493                 return 0;
1494
1495         /*
1496          * Install GPE handler
1497          */
1498         status = acpi_install_gpe_handler(NULL, ec_ecdt->common.gpe_bit,
1499                                           ACPI_GPE_EDGE_TRIGGERED,
1500                                           &acpi_ec_gpe_handler, ec_ecdt);
1501         if (ACPI_FAILURE(status)) {
1502                 goto error;
1503         }
1504         acpi_set_gpe_type(NULL, ec_ecdt->common.gpe_bit, ACPI_GPE_TYPE_RUNTIME);
1505         acpi_enable_gpe(NULL, ec_ecdt->common.gpe_bit, ACPI_NOT_ISR);
1506
1507         status = acpi_install_address_space_handler(ACPI_ROOT_OBJECT,
1508                                                     ACPI_ADR_SPACE_EC,
1509                                                     &acpi_ec_space_handler,
1510                                                     &acpi_ec_space_setup,
1511                                                     ec_ecdt);
1512         if (ACPI_FAILURE(status)) {
1513                 acpi_remove_gpe_handler(NULL, ec_ecdt->common.gpe_bit,
1514                                         &acpi_ec_gpe_handler);
1515                 goto error;
1516         }
1517
1518         return 0;
1519
1520       error:
1521         printk(KERN_ERR PREFIX "Could not use ECDT\n");
1522         kfree(ec_ecdt);
1523         ec_ecdt = NULL;
1524
1525         return -ENODEV;
1526 }
1527
1528 static int __init acpi_ec_init(void)
1529 {
1530         int result = 0;
1531
1532         ACPI_FUNCTION_TRACE("acpi_ec_init");
1533
1534         if (acpi_disabled)
1535                 return_VALUE(0);
1536
1537         acpi_ec_dir = proc_mkdir(ACPI_EC_CLASS, acpi_root_dir);
1538         if (!acpi_ec_dir)
1539                 return_VALUE(-ENODEV);
1540
1541         /* Now register the driver for the EC */
1542         result = acpi_bus_register_driver(&acpi_ec_driver);
1543         if (result < 0) {
1544                 remove_proc_entry(ACPI_EC_CLASS, acpi_root_dir);
1545                 return_VALUE(-ENODEV);
1546         }
1547
1548         return_VALUE(result);
1549 }
1550
1551 subsys_initcall(acpi_ec_init);
1552
1553 /* EC driver currently not unloadable */
1554 #if 0
1555 static void __exit acpi_ec_exit(void)
1556 {
1557         ACPI_FUNCTION_TRACE("acpi_ec_exit");
1558
1559         acpi_bus_unregister_driver(&acpi_ec_driver);
1560
1561         remove_proc_entry(ACPI_EC_CLASS, acpi_root_dir);
1562
1563         return_VOID;
1564 }
1565 #endif                          /* 0 */
1566
1567 static int __init acpi_fake_ecdt_setup(char *str)
1568 {
1569         acpi_fake_ecdt_enabled = 1;
1570         return 0;
1571 }
1572
1573 __setup("acpi_fake_ecdt", acpi_fake_ecdt_setup);
1574 static int __init acpi_ec_set_polling_mode(char *str)
1575 {
1576         int burst;
1577
1578         if (!get_option(&str, &burst))
1579                 return 0;
1580
1581         if (burst) {
1582                 acpi_ec_polling_mode = EC_BURST;
1583                 acpi_ec_driver.ops.add = acpi_ec_burst_add;
1584         } else {
1585                 acpi_ec_polling_mode = EC_POLLING;
1586                 acpi_ec_driver.ops.add = acpi_ec_polling_add;
1587         }
1588         printk(KERN_INFO PREFIX "EC %s mode.\n", burst ? "burst" : "polling");
1589         return 0;
1590 }
1591
1592 __setup("ec_burst=", acpi_ec_set_polling_mode);