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         result = wait_event_interruptible_timeout(ec->burst.wait,
 216                                                   !ec->burst.expect_event,
 217                                                   msecs_to_jiffies
 218                                                   (ACPI_EC_DELAY));
 219
 220         ec->burst.expect_event = 0;
 221         smp_mb();
 222
 223         if (result < 0) {
 224                 ACPI_DEBUG_PRINT((ACPI_DB_ERROR, " result  = %d ", result));
 225                 return_VALUE(result);
 226         }
 227
 228         /*
 229          * Verify that the event in question has actually happened by
 230          * querying EC status. Do the check even if operation timed-out
 231          * to make sure that we did not miss interrupt.
 232          */
 233         switch (event) {
 234         case ACPI_EC_EVENT_OBF:
 235                 if (acpi_ec_read_status(ec) & ACPI_EC_FLAG_OBF)
 236                         return_VALUE(0);
 237                 break;
 238
 239         case ACPI_EC_EVENT_IBE:
 240                 if (~acpi_ec_read_status(ec) & ACPI_EC_FLAG_IBF)
 241                         return_VALUE(0);
 242                 break;
 243         }
 244
 245         return_VALUE(-ETIME);
 246 }
 247
 248 static int acpi_ec_enter_burst_mode(union acpi_ec *ec)
 249 {
 250         u32 tmp = 0;
 251         int status = 0;
 252
 253         ACPI_FUNCTION_TRACE("acpi_ec_enter_burst_mode");
 254
 255         status = acpi_ec_read_status(ec);
 256         if (status != -EINVAL && !(status & ACPI_EC_FLAG_BURST)) {
 257                 acpi_hw_low_level_write(8, ACPI_EC_BURST_ENABLE,
 258                                         &ec->common.command_addr);
 259                 status = acpi_ec_wait(ec, ACPI_EC_EVENT_OBF);
 260                 if (status) {
 261                         acpi_enable_gpe(NULL, ec->common.gpe_bit, ACPI_NOT_ISR);
 262                         return_VALUE(-EINVAL);
 263                 }
 264                 acpi_hw_low_level_read(8, &tmp, &ec->common.data_addr);
 265                 acpi_enable_gpe(NULL, ec->common.gpe_bit, ACPI_NOT_ISR);
 266                 if (tmp != 0x90) {      /* Burst ACK byte */
 267                         return_VALUE(-EINVAL);
 268                 }
 269         }
 270
 271         atomic_set(&ec->burst.leaving_burst, 0);
 272         return_VALUE(0);
 273 }
 274
 275 static int acpi_ec_leave_burst_mode(union acpi_ec *ec)
 276 {
 277         int status = 0;
 278
 279         ACPI_FUNCTION_TRACE("acpi_ec_leave_burst_mode");
 280
 281         atomic_set(&ec->burst.leaving_burst, 1);
 282         status = acpi_ec_read_status(ec);
 283         if (status != -EINVAL && (status & ACPI_EC_FLAG_BURST)) {
 284                 acpi_hw_low_level_write(8, ACPI_EC_BURST_DISABLE,
 285                                         &ec->common.command_addr);
 286                 status = acpi_ec_wait(ec, ACPI_EC_FLAG_IBF);
 287                 if (status) {
 288                         acpi_enable_gpe(NULL, ec->common.gpe_bit, ACPI_NOT_ISR);
 289                         ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
 290                                           "------->wait fail\n"));
 291                         return_VALUE(-EINVAL);
 292                 }
 293                 acpi_enable_gpe(NULL, ec->common.gpe_bit, ACPI_NOT_ISR);
 294                 status = acpi_ec_read_status(ec);
 295         }
 296
 297         return_VALUE(0);
 298 }
 299
 300 static int acpi_ec_read(union acpi_ec *ec, u8 address, u32 * data)
 301 {
 302         if (acpi_ec_polling_mode)
 303                 return acpi_ec_polling_read(ec, address, data);
 304         else
 305                 return acpi_ec_burst_read(ec, address, data);
 306 }
 307 static int acpi_ec_write(union acpi_ec *ec, u8 address, u8 data)
 308 {
 309         if (acpi_ec_polling_mode)
 310                 return acpi_ec_polling_write(ec, address, data);
 311         else
 312                 return acpi_ec_burst_write(ec, address, data);
 313 }
 314 static int acpi_ec_polling_read(union acpi_ec *ec, u8 address, u32 * data)
 315 {
 316         acpi_status status = AE_OK;
 317         int result = 0;
 318         unsigned long flags = 0;
 319         u32 glk = 0;
 320
 321         ACPI_FUNCTION_TRACE("acpi_ec_read");
 322
 323         if (!ec || !data)
 324                 return_VALUE(-EINVAL);
 325
 326         *data = 0;
 327
 328         if (ec->common.global_lock) {
 329                 status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk);
 330                 if (ACPI_FAILURE(status))
 331                         return_VALUE(-ENODEV);
 332         }
 333
 334         spin_lock_irqsave(&ec->polling.lock, flags);
 335
 336         acpi_hw_low_level_write(8, ACPI_EC_COMMAND_READ,
 337                                 &ec->common.command_addr);
 338         result = acpi_ec_wait(ec, ACPI_EC_EVENT_IBE);
 339         if (result)
 340                 goto end;
 341
 342         acpi_hw_low_level_write(8, address, &ec->common.data_addr);
 343         result = acpi_ec_wait(ec, ACPI_EC_EVENT_OBF);
 344         if (result)
 345                 goto end;
 346
 347         acpi_hw_low_level_read(8, data, &ec->common.data_addr);
 348
 349         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Read [%02x] from address [%02x]\n",
 350                           *data, address));
 351
 352       end:
 353         spin_unlock_irqrestore(&ec->polling.lock, flags);
 354
 355         if (ec->common.global_lock)
 356                 acpi_release_global_lock(glk);
 357
 358         return_VALUE(result);
 359 }
 360
 361 static int acpi_ec_polling_write(union acpi_ec *ec, u8 address, u8 data)
 362 {
 363         int result = 0;
 364         acpi_status status = AE_OK;
 365         unsigned long flags = 0;
 366         u32 glk = 0;
 367
 368         ACPI_FUNCTION_TRACE("acpi_ec_write");
 369
 370         if (!ec)
 371                 return_VALUE(-EINVAL);
 372
 373         if (ec->common.global_lock) {
 374                 status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk);
 375                 if (ACPI_FAILURE(status))
 376                         return_VALUE(-ENODEV);
 377         }
 378
 379         spin_lock_irqsave(&ec->polling.lock, flags);
 380
 381         acpi_hw_low_level_write(8, ACPI_EC_COMMAND_WRITE,
 382                                 &ec->common.command_addr);
 383         result = acpi_ec_wait(ec, ACPI_EC_EVENT_IBE);
 384         if (result)
 385                 goto end;
 386
 387         acpi_hw_low_level_write(8, address, &ec->common.data_addr);
 388         result = acpi_ec_wait(ec, ACPI_EC_EVENT_IBE);
 389         if (result)
 390                 goto end;
 391
 392         acpi_hw_low_level_write(8, data, &ec->common.data_addr);
 393         result = acpi_ec_wait(ec, ACPI_EC_EVENT_IBE);
 394         if (result)
 395                 goto end;
 396
 397         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Wrote [%02x] to address [%02x]\n",
 398                           data, address));
 399
 400       end:
 401         spin_unlock_irqrestore(&ec->polling.lock, flags);
 402
 403         if (ec->common.global_lock)
 404                 acpi_release_global_lock(glk);
 405
 406         return_VALUE(result);
 407 }
 408
 409 static int acpi_ec_burst_read(union acpi_ec *ec, u8 address, u32 * data)
 410 {
 411         int status = 0;
 412         u32 glk;
 413
 414         ACPI_FUNCTION_TRACE("acpi_ec_read");
 415
 416         if (!ec || !data)
 417                 return_VALUE(-EINVAL);
 418
 419       retry:
 420         *data = 0;
 421
 422         if (ec->common.global_lock) {
 423                 status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk);
 424                 if (ACPI_FAILURE(status))
 425                         return_VALUE(-ENODEV);
 426         }
 427
 428         WARN_ON(in_interrupt());
 429         down(&ec->burst.sem);
 430
 431         if (acpi_ec_enter_burst_mode(ec))
 432                 goto end;
 433
 434         acpi_hw_low_level_write(8, ACPI_EC_COMMAND_READ,
 435                                 &ec->common.command_addr);
 436         status = acpi_ec_wait(ec, ACPI_EC_EVENT_IBE);
 437         acpi_enable_gpe(NULL, ec->common.gpe_bit, ACPI_NOT_ISR);
 438         if (status) {
 439                 goto end;
 440         }
 441
 442         acpi_hw_low_level_write(8, address, &ec->common.data_addr);
 443         status = acpi_ec_wait(ec, ACPI_EC_EVENT_OBF);
 444         if (status) {
 445                 acpi_enable_gpe(NULL, ec->common.gpe_bit, ACPI_NOT_ISR);
 446                 goto end;
 447         }
 448
 449         acpi_hw_low_level_read(8, data, &ec->common.data_addr);
 450         acpi_enable_gpe(NULL, ec->common.gpe_bit, ACPI_NOT_ISR);
 451
 452         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Read [%02x] from address [%02x]\n",
 453                           *data, address));
 454
 455       end:
 456         acpi_ec_leave_burst_mode(ec);
 457         up(&ec->burst.sem);
 458
 459         if (ec->common.global_lock)
 460                 acpi_release_global_lock(glk);
 461
 462         if (atomic_read(&ec->burst.leaving_burst) == 2) {
 463                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "aborted, retry ...\n"));
 464                 while (atomic_read(&ec->burst.pending_gpe)) {
 465                         msleep(1);
 466                 }
 467                 acpi_enable_gpe(NULL, ec->common.gpe_bit, ACPI_NOT_ISR);
 468                 goto retry;
 469         }
 470
 471         return_VALUE(status);
 472 }
 473
 474 static int acpi_ec_burst_write(union acpi_ec *ec, u8 address, u8 data)
 475 {
 476         int status = 0;
 477         u32 glk;
 478         u32 tmp;
 479
 480         ACPI_FUNCTION_TRACE("acpi_ec_write");
 481
 482         if (!ec)
 483                 return_VALUE(-EINVAL);
 484       retry:
 485         if (ec->common.global_lock) {
 486                 status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk);
 487                 if (ACPI_FAILURE(status))
 488                         return_VALUE(-ENODEV);
 489         }
 490
 491         WARN_ON(in_interrupt());
 492         down(&ec->burst.sem);
 493
 494         if (acpi_ec_enter_burst_mode(ec))
 495                 goto end;
 496
 497         status = acpi_ec_read_status(ec);
 498         if (status != -EINVAL && !(status & ACPI_EC_FLAG_BURST)) {
 499                 acpi_hw_low_level_write(8, ACPI_EC_BURST_ENABLE,
 500                                         &ec->common.command_addr);
 501                 status = acpi_ec_wait(ec, ACPI_EC_EVENT_OBF);
 502                 if (status)
 503                         goto end;
 504                 acpi_hw_low_level_read(8, &tmp, &ec->common.data_addr);
 505                 if (tmp != 0x90)        /* Burst ACK byte */
 506                         goto end;
 507         }
 508         /*Now we are in burst mode */
 509
 510         acpi_hw_low_level_write(8, ACPI_EC_COMMAND_WRITE,
 511                                 &ec->common.command_addr);
 512         status = acpi_ec_wait(ec, ACPI_EC_EVENT_IBE);
 513         acpi_enable_gpe(NULL, ec->common.gpe_bit, ACPI_NOT_ISR);
 514         if (status) {
 515                 goto end;
 516         }
 517
 518         acpi_hw_low_level_write(8, address, &ec->common.data_addr);
 519         status = acpi_ec_wait(ec, ACPI_EC_EVENT_IBE);
 520         if (status) {
 521                 acpi_enable_gpe(NULL, ec->common.gpe_bit, ACPI_NOT_ISR);
 522                 goto end;
 523         }
 524
 525         acpi_hw_low_level_write(8, data, &ec->common.data_addr);
 526         status = acpi_ec_wait(ec, ACPI_EC_EVENT_IBE);
 527         acpi_enable_gpe(NULL, ec->common.gpe_bit, ACPI_NOT_ISR);
 528         if (status)
 529                 goto end;
 530
 531         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Wrote [%02x] to address [%02x]\n",
 532                           data, address));
 533
 534       end:
 535         acpi_ec_leave_burst_mode(ec);
 536         up(&ec->burst.sem);
 537
 538         if (ec->common.global_lock)
 539                 acpi_release_global_lock(glk);
 540
 541         if (atomic_read(&ec->burst.leaving_burst) == 2) {
 542                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "aborted, retry ...\n"));
 543                 while (atomic_read(&ec->burst.pending_gpe)) {
 544                         msleep(1);
 545                 }
 546                 acpi_enable_gpe(NULL, ec->common.gpe_bit, ACPI_NOT_ISR);
 547                 goto retry;
 548         }
 549
 550         return_VALUE(status);
 551 }
 552
 553 /*
 554  * Externally callable EC access functions. For now, assume 1 EC only
 555  */
 556 int ec_read(u8 addr, u8 * val)
 557 {
 558         union acpi_ec *ec;
 559         int err;
 560         u32 temp_data;
 561
 562         if (!first_ec)
 563                 return -ENODEV;
 564
 565         ec = acpi_driver_data(first_ec);
 566
 567         err = acpi_ec_read(ec, addr, &temp_data);
 568
 569         if (!err) {
 570                 *val = temp_data;
 571                 return 0;
 572         } else
 573                 return err;
 574 }
 575
 576 EXPORT_SYMBOL(ec_read);
 577
 578 int ec_write(u8 addr, u8 val)
 579 {
 580         union acpi_ec *ec;
 581         int err;
 582
 583         if (!first_ec)
 584                 return -ENODEV;
 585
 586         ec = acpi_driver_data(first_ec);
 587
 588         err = acpi_ec_write(ec, addr, val);
 589
 590         return err;
 591 }
 592
 593 EXPORT_SYMBOL(ec_write);
 594
 595 static int acpi_ec_query(union acpi_ec *ec, u32 * data)
 596 {
 597         if (acpi_ec_polling_mode)
 598                 return acpi_ec_polling_query(ec, data);
 599         else
 600                 return acpi_ec_burst_query(ec, data);
 601 }
 602 static int acpi_ec_polling_query(union acpi_ec *ec, u32 * data)
 603 {
 604         int result = 0;
 605         acpi_status status = AE_OK;
 606         unsigned long flags = 0;
 607         u32 glk = 0;
 608
 609         ACPI_FUNCTION_TRACE("acpi_ec_query");
 610
 611         if (!ec || !data)
 612                 return_VALUE(-EINVAL);
 613
 614         *data = 0;
 615
 616         if (ec->common.global_lock) {
 617                 status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk);
 618                 if (ACPI_FAILURE(status))
 619                         return_VALUE(-ENODEV);
 620         }
 621
 622         /*
 623          * Query the EC to find out which _Qxx method we need to evaluate.
 624          * Note that successful completion of the query causes the ACPI_EC_SCI
 625          * bit to be cleared (and thus clearing the interrupt source).
 626          */
 627         spin_lock_irqsave(&ec->polling.lock, flags);
 628
 629         acpi_hw_low_level_write(8, ACPI_EC_COMMAND_QUERY,
 630                                 &ec->common.command_addr);
 631         result = acpi_ec_wait(ec, ACPI_EC_EVENT_OBF);
 632         if (result)
 633                 goto end;
 634
 635         acpi_hw_low_level_read(8, data, &ec->common.data_addr);
 636         if (!*data)
 637                 result = -ENODATA;
 638
 639       end:
 640         spin_unlock_irqrestore(&ec->polling.lock, flags);
 641
 642         if (ec->common.global_lock)
 643                 acpi_release_global_lock(glk);
 644
 645         return_VALUE(result);
 646 }
 647 static int acpi_ec_burst_query(union acpi_ec *ec, u32 * data)
 648 {
 649         int status = 0;
 650         u32 glk;
 651
 652         ACPI_FUNCTION_TRACE("acpi_ec_query");
 653
 654         if (!ec || !data)
 655                 return_VALUE(-EINVAL);
 656         *data = 0;
 657
 658         if (ec->common.global_lock) {
 659                 status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk);
 660                 if (ACPI_FAILURE(status))
 661                         return_VALUE(-ENODEV);
 662         }
 663
 664         down(&ec->burst.sem);
 665         if (acpi_ec_enter_burst_mode(ec))
 666                 goto end;
 667         /*
 668          * Query the EC to find out which _Qxx method we need to evaluate.
 669          * Note that successful completion of the query causes the ACPI_EC_SCI
 670          * bit to be cleared (and thus clearing the interrupt source).
 671          */
 672         acpi_hw_low_level_write(8, ACPI_EC_COMMAND_QUERY,
 673                                 &ec->common.command_addr);
 674         status = acpi_ec_wait(ec, ACPI_EC_EVENT_OBF);
 675         if (status) {
 676                 acpi_enable_gpe(NULL, ec->common.gpe_bit, ACPI_NOT_ISR);
 677                 goto end;
 678         }
 679
 680         acpi_hw_low_level_read(8, data, &ec->common.data_addr);
 681         acpi_enable_gpe(NULL, ec->common.gpe_bit, ACPI_NOT_ISR);
 682         if (!*data)
 683                 status = -ENODATA;
 684
 685       end:
 686         acpi_ec_leave_burst_mode(ec);
 687         up(&ec->burst.sem);
 688
 689         if (ec->common.global_lock)
 690                 acpi_release_global_lock(glk);
 691
 692         if (atomic_read(&ec->burst.leaving_burst) == 2) {
 693                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "aborted, retry ...\n"));
 694                 acpi_enable_gpe(NULL, ec->common.gpe_bit, ACPI_NOT_ISR);
 695                 status = -ENODATA;
 696         }
 697         return_VALUE(status);
 698 }
 699
 700 /* --------------------------------------------------------------------------
 701                                 Event Management
 702    -------------------------------------------------------------------------- */
 703
 704 union acpi_ec_query_data {
 705         acpi_handle handle;
 706         u8 data;
 707 };
 708
 709 static void acpi_ec_gpe_query(void *ec_cxt)
 710 {
 711         if (acpi_ec_polling_mode)
 712                 acpi_ec_gpe_polling_query(ec_cxt);
 713         else
 714                 acpi_ec_gpe_burst_query(ec_cxt);
 715 }
 716
 717 static void acpi_ec_gpe_polling_query(void *ec_cxt)
 718 {
 719         union acpi_ec *ec = (union acpi_ec *)ec_cxt;
 720         u32 value = 0;
 721         unsigned long flags = 0;
 722         static char object_name[5] = { '_', 'Q', '0', '0', '\0' };
 723         const char hex[] = { '0', '1', '2', '3', '4', '5', '6', '7',
 724                 '8', '9', 'A', 'B', 'C', 'D', 'E', 'F'
 725         };
 726
 727         ACPI_FUNCTION_TRACE("acpi_ec_gpe_query");
 728
 729         if (!ec_cxt)
 730                 goto end;
 731
 732         spin_lock_irqsave(&ec->polling.lock, flags);
 733         acpi_hw_low_level_read(8, &value, &ec->common.command_addr);
 734         spin_unlock_irqrestore(&ec->polling.lock, flags);
 735
 736         /* TBD: Implement asynch events!
 737          * NOTE: All we care about are EC-SCI's.  Other EC events are
 738          * handled via polling (yuck!).  This is because some systems
 739          * treat EC-SCIs as level (versus EDGE!) triggered, preventing
 740          *  a purely interrupt-driven approach (grumble, grumble).
 741          */
 742         if (!(value & ACPI_EC_FLAG_SCI))
 743                 goto end;
 744
 745         if (acpi_ec_query(ec, &value))
 746                 goto end;
 747
 748         object_name[2] = hex[((value >> 4) & 0x0F)];
 749         object_name[3] = hex[(value & 0x0F)];
 750
 751         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Evaluating %s\n", object_name));
 752
 753         acpi_evaluate_object(ec->common.handle, object_name, NULL, NULL);
 754
 755       end:
 756         acpi_enable_gpe(NULL, ec->common.gpe_bit, ACPI_NOT_ISR);
 757 }
 758 static void acpi_ec_gpe_burst_query(void *ec_cxt)
 759 {
 760         union acpi_ec *ec = (union acpi_ec *)ec_cxt;
 761         u32 value;
 762         int result = -ENODATA;
 763         static char object_name[5] = { '_', 'Q', '0', '0', '\0' };
 764         const char hex[] = { '0', '1', '2', '3', '4', '5', '6', '7',
 765                 '8', '9', 'A', 'B', 'C', 'D', 'E', 'F'
 766         };
 767
 768         ACPI_FUNCTION_TRACE("acpi_ec_gpe_query");
 769
 770         if (acpi_ec_read_status(ec) & ACPI_EC_FLAG_SCI)
 771                 result = acpi_ec_query(ec, &value);
 772
 773         if (result)
 774                 goto end;
 775
 776         object_name[2] = hex[((value >> 4) & 0x0F)];
 777         object_name[3] = hex[(value & 0x0F)];
 778
 779         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Evaluating %s\n", object_name));
 780
 781         acpi_evaluate_object(ec->common.handle, object_name, NULL, NULL);
 782       end:
 783         atomic_dec(&ec->burst.pending_gpe);
 784         return;
 785 }
 786
 787 static u32 acpi_ec_gpe_handler(void *data)
 788 {
 789         if (acpi_ec_polling_mode)
 790                 return acpi_ec_gpe_polling_handler(data);
 791         else
 792                 return acpi_ec_gpe_burst_handler(data);
 793 }
 794 static u32 acpi_ec_gpe_polling_handler(void *data)
 795 {
 796         acpi_status status = AE_OK;
 797         union acpi_ec *ec = (union acpi_ec *)data;
 798
 799         if (!ec)
 800                 return ACPI_INTERRUPT_NOT_HANDLED;
 801
 802         acpi_disable_gpe(NULL, ec->common.gpe_bit, ACPI_ISR);
 803
 804         status = acpi_os_queue_for_execution(OSD_PRIORITY_GPE,
 805                                              acpi_ec_gpe_query, ec);
 806
 807         if (status == AE_OK)
 808                 return ACPI_INTERRUPT_HANDLED;
 809         else
 810                 return ACPI_INTERRUPT_NOT_HANDLED;
 811 }
 812 static u32 acpi_ec_gpe_burst_handler(void *data)
 813 {
 814         acpi_status status = AE_OK;
 815         u32 value;
 816         union acpi_ec *ec = (union acpi_ec *)data;
 817
 818         if (!ec)
 819                 return ACPI_INTERRUPT_NOT_HANDLED;
 820
 821         acpi_disable_gpe(NULL, ec->common.gpe_bit, ACPI_ISR);
 822
 823         value = acpi_ec_read_status(ec);
 824
 825         if ((value & ACPI_EC_FLAG_IBF) &&
 826             !(value & ACPI_EC_FLAG_BURST) &&
 827             (atomic_read(&ec->burst.leaving_burst) == 0)) {
 828                 /*
 829                  * the embedded controller disables
 830                  * burst mode for any reason other
 831                  * than the burst disable command
 832                  * to process critical event.
 833                  */
 834                 atomic_set(&ec->burst.leaving_burst, 2);        /* block current pending transaction
 835                                                                    and retry */
 836                 wake_up(&ec->burst.wait);
 837         } else {
 838                 if ((ec->burst.expect_event == ACPI_EC_EVENT_OBF &&
 839                      (value & ACPI_EC_FLAG_OBF)) ||
 840                     (ec->burst.expect_event == ACPI_EC_EVENT_IBE &&
 841                      !(value & ACPI_EC_FLAG_IBF))) {
 842                         ec->burst.expect_event = 0;
 843                         wake_up(&ec->burst.wait);
 844                         return ACPI_INTERRUPT_HANDLED;
 845                 }
 846         }
 847
 848         if (value & ACPI_EC_FLAG_SCI) {
 849                 atomic_add(1, &ec->burst.pending_gpe);
 850                 status = acpi_os_queue_for_execution(OSD_PRIORITY_GPE,
 851                                                      acpi_ec_gpe_query, ec);
 852                 return status == AE_OK ?
 853                     ACPI_INTERRUPT_HANDLED : ACPI_INTERRUPT_NOT_HANDLED;
 854         }
 855         acpi_enable_gpe(NULL, ec->common.gpe_bit, ACPI_ISR);
 856         return status == AE_OK ?
 857             ACPI_INTERRUPT_HANDLED : ACPI_INTERRUPT_NOT_HANDLED;
 858 }
 859
 860 /* --------------------------------------------------------------------------
 861                              Address Space Management
 862    -------------------------------------------------------------------------- */
 863
 864 static acpi_status
 865 acpi_ec_space_setup(acpi_handle region_handle,
 866                     u32 function, void *handler_context, void **return_context)
 867 {
 868         /*
 869          * The EC object is in the handler context and is needed
 870          * when calling the acpi_ec_space_handler.
 871          */
 872         *return_context = (function != ACPI_REGION_DEACTIVATE) ?
 873             handler_context : NULL;
 874
 875         return AE_OK;
 876 }
 877
 878 static acpi_status
 879 acpi_ec_space_handler(u32 function,
 880                       acpi_physical_address address,
 881                       u32 bit_width,
 882                       acpi_integer * value,
 883                       void *handler_context, void *region_context)
 884 {
 885         int result = 0;
 886         union acpi_ec *ec = NULL;
 887         u64 temp = *value;
 888         acpi_integer f_v = 0;
 889         int i = 0;
 890
 891         ACPI_FUNCTION_TRACE("acpi_ec_space_handler");
 892
 893         if ((address > 0xFF) || !value || !handler_context)
 894                 return_VALUE(AE_BAD_PARAMETER);
 895
 896         if (bit_width != 8 && acpi_strict) {
 897                 printk(KERN_WARNING PREFIX
 898                        "acpi_ec_space_handler: bit_width should be 8\n");
 899                 return_VALUE(AE_BAD_PARAMETER);
 900         }
 901
 902         ec = (union acpi_ec *)handler_context;
 903
 904       next_byte:
 905         switch (function) {
 906         case ACPI_READ:
 907                 temp = 0;
 908                 result = acpi_ec_read(ec, (u8) address, (u32 *) & temp);
 909                 break;
 910         case ACPI_WRITE:
 911                 result = acpi_ec_write(ec, (u8) address, (u8) temp);
 912                 break;
 913         default:
 914                 result = -EINVAL;
 915                 goto out;
 916                 break;
 917         }
 918
 919         bit_width -= 8;
 920         if (bit_width) {
 921                 if (function == ACPI_READ)
 922                         f_v |= temp << 8 * i;
 923                 if (function == ACPI_WRITE)
 924                         temp >>= 8;
 925                 i++;
 926                 address++;
 927                 goto next_byte;
 928         }
 929
 930         if (function == ACPI_READ) {
 931                 f_v |= temp << 8 * i;
 932                 *value = f_v;
 933         }
 934
 935       out:
 936         switch (result) {
 937         case -EINVAL:
 938                 return_VALUE(AE_BAD_PARAMETER);
 939                 break;
 940         case -ENODEV:
 941                 return_VALUE(AE_NOT_FOUND);
 942                 break;
 943         case -ETIME:
 944                 return_VALUE(AE_TIME);
 945                 break;
 946         default:
 947                 return_VALUE(AE_OK);
 948         }
 949 }
 950
 951 /* --------------------------------------------------------------------------
 952                               FS Interface (/proc)
 953    -------------------------------------------------------------------------- */
 954
 955 static struct proc_dir_entry *acpi_ec_dir;
 956
 957 static int acpi_ec_read_info(struct seq_file *seq, void *offset)
 958 {
 959         union acpi_ec *ec = (union acpi_ec *)seq->private;
 960
 961         ACPI_FUNCTION_TRACE("acpi_ec_read_info");
 962
 963         if (!ec)
 964                 goto end;
 965
 966         seq_printf(seq, "gpe bit:                 0x%02x\n",
 967                    (u32) ec->common.gpe_bit);
 968         seq_printf(seq, "ports:                   0x%02x, 0x%02x\n",
 969                    (u32) ec->common.status_addr.address,
 970                    (u32) ec->common.data_addr.address);
 971         seq_printf(seq, "use global lock:         %s\n",
 972                    ec->common.global_lock ? "yes" : "no");
 973         acpi_enable_gpe(NULL, ec->common.gpe_bit, ACPI_NOT_ISR);
 974
 975       end:
 976         return_VALUE(0);
 977 }
 978
 979 static int acpi_ec_info_open_fs(struct inode *inode, struct file *file)
 980 {
 981         return single_open(file, acpi_ec_read_info, PDE(inode)->data);
 982 }
 983
 984 static struct file_operations acpi_ec_info_ops = {
 985         .open = acpi_ec_info_open_fs,
 986         .read = seq_read,
 987         .llseek = seq_lseek,
 988         .release = single_release,
 989         .owner = THIS_MODULE,
 990 };
 991
 992 static int acpi_ec_add_fs(struct acpi_device *device)
 993 {
 994         struct proc_dir_entry *entry = NULL;
 995
 996         ACPI_FUNCTION_TRACE("acpi_ec_add_fs");
 997
 998         if (!acpi_device_dir(device)) {
 999                 acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device),
1000                                                      acpi_ec_dir);
1001                 if (!acpi_device_dir(device))
1002                         return_VALUE(-ENODEV);
1003         }
1004
1005         entry = create_proc_entry(ACPI_EC_FILE_INFO, S_IRUGO,
1006                                   acpi_device_dir(device));
1007         if (!entry)
1008                 ACPI_DEBUG_PRINT((ACPI_DB_WARN,
1009                                   "Unable to create '%s' fs entry\n",
1010                                   ACPI_EC_FILE_INFO));
1011         else {
1012                 entry->proc_fops = &acpi_ec_info_ops;
1013                 entry->data = acpi_driver_data(device);
1014                 entry->owner = THIS_MODULE;
1015         }
1016
1017         return_VALUE(0);
1018 }
1019
1020 static int acpi_ec_remove_fs(struct acpi_device *device)
1021 {
1022         ACPI_FUNCTION_TRACE("acpi_ec_remove_fs");
1023
1024         if (acpi_device_dir(device)) {
1025                 remove_proc_entry(ACPI_EC_FILE_INFO, acpi_device_dir(device));
1026                 remove_proc_entry(acpi_device_bid(device), acpi_ec_dir);
1027                 acpi_device_dir(device) = NULL;
1028         }
1029
1030         return_VALUE(0);
1031 }
1032
1033 /* --------------------------------------------------------------------------
1034                                Driver Interface
1035    -------------------------------------------------------------------------- */
1036
1037 static int acpi_ec_polling_add(struct acpi_device *device)
1038 {
1039         int result = 0;
1040         acpi_status status = AE_OK;
1041         union acpi_ec *ec = NULL;
1042         unsigned long uid;
1043
1044         ACPI_FUNCTION_TRACE("acpi_ec_add");
1045
1046         if (!device)
1047                 return_VALUE(-EINVAL);
1048
1049         ec = kmalloc(sizeof(union acpi_ec), GFP_KERNEL);
1050         if (!ec)
1051                 return_VALUE(-ENOMEM);
1052         memset(ec, 0, sizeof(union acpi_ec));
1053
1054         ec->common.handle = device->handle;
1055         ec->common.uid = -1;
1056         spin_lock_init(&ec->polling.lock);
1057         strcpy(acpi_device_name(device), ACPI_EC_DEVICE_NAME);
1058         strcpy(acpi_device_class(device), ACPI_EC_CLASS);
1059         acpi_driver_data(device) = ec;
1060
1061         /* Use the global lock for all EC transactions? */
1062         acpi_evaluate_integer(ec->common.handle, "_GLK", NULL,
1063                               &ec->common.global_lock);
1064
1065         /* If our UID matches the UID for the ECDT-enumerated EC,
1066            we now have the *real* EC info, so kill the makeshift one. */
1067         acpi_evaluate_integer(ec->common.handle, "_UID", NULL, &uid);
1068         if (ec_ecdt && ec_ecdt->common.uid == uid) {
1069                 acpi_remove_address_space_handler(ACPI_ROOT_OBJECT,
1070                                                   ACPI_ADR_SPACE_EC,
1071                                                   &acpi_ec_space_handler);
1072
1073                 acpi_remove_gpe_handler(NULL, ec_ecdt->common.gpe_bit,
1074                                         &acpi_ec_gpe_handler);
1075
1076                 kfree(ec_ecdt);
1077         }
1078
1079         /* Get GPE bit assignment (EC events). */
1080         /* TODO: Add support for _GPE returning a package */
1081         status =
1082             acpi_evaluate_integer(ec->common.handle, "_GPE", NULL,
1083                                   &ec->common.gpe_bit);
1084         if (ACPI_FAILURE(status)) {
1085                 ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
1086                                   "Error obtaining GPE bit assignment\n"));
1087                 result = -ENODEV;
1088                 goto end;
1089         }
1090
1091         result = acpi_ec_add_fs(device);
1092         if (result)
1093                 goto end;
1094
1095         printk(KERN_INFO PREFIX "%s [%s] (gpe %d)\n",
1096                acpi_device_name(device), acpi_device_bid(device),
1097                (u32) ec->common.gpe_bit);
1098
1099         if (!first_ec)
1100                 first_ec = device;
1101
1102       end:
1103         if (result)
1104                 kfree(ec);
1105
1106         return_VALUE(result);
1107 }
1108 static int acpi_ec_burst_add(struct acpi_device *device)
1109 {
1110         int result = 0;
1111         acpi_status status = AE_OK;
1112         union acpi_ec *ec = NULL;
1113         unsigned long uid;
1114
1115         ACPI_FUNCTION_TRACE("acpi_ec_add");
1116
1117         if (!device)
1118                 return_VALUE(-EINVAL);
1119
1120         ec = kmalloc(sizeof(union acpi_ec), GFP_KERNEL);
1121         if (!ec)
1122                 return_VALUE(-ENOMEM);
1123         memset(ec, 0, sizeof(union acpi_ec));
1124
1125         ec->common.handle = device->handle;
1126         ec->common.uid = -1;
1127         atomic_set(&ec->burst.pending_gpe, 0);
1128         atomic_set(&ec->burst.leaving_burst, 1);
1129         init_MUTEX(&ec->burst.sem);
1130         init_waitqueue_head(&ec->burst.wait);
1131         strcpy(acpi_device_name(device), ACPI_EC_DEVICE_NAME);
1132         strcpy(acpi_device_class(device), ACPI_EC_CLASS);
1133         acpi_driver_data(device) = ec;
1134
1135         /* Use the global lock for all EC transactions? */
1136         acpi_evaluate_integer(ec->common.handle, "_GLK", NULL,
1137                               &ec->common.global_lock);
1138
1139         /* If our UID matches the UID for the ECDT-enumerated EC,
1140            we now have the *real* EC info, so kill the makeshift one. */
1141         acpi_evaluate_integer(ec->common.handle, "_UID", NULL, &uid);
1142         if (ec_ecdt && ec_ecdt->common.uid == uid) {
1143                 acpi_remove_address_space_handler(ACPI_ROOT_OBJECT,
1144                                                   ACPI_ADR_SPACE_EC,
1145                                                   &acpi_ec_space_handler);
1146
1147                 acpi_remove_gpe_handler(NULL, ec_ecdt->common.gpe_bit,
1148                                         &acpi_ec_gpe_handler);
1149
1150                 kfree(ec_ecdt);
1151         }
1152
1153         /* Get GPE bit assignment (EC events). */
1154         /* TODO: Add support for _GPE returning a package */
1155         status =
1156             acpi_evaluate_integer(ec->common.handle, "_GPE", NULL,
1157                                   &ec->common.gpe_bit);
1158         if (ACPI_FAILURE(status)) {
1159                 ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
1160                                   "Error obtaining GPE bit assignment\n"));
1161                 result = -ENODEV;
1162                 goto end;
1163         }
1164
1165         result = acpi_ec_add_fs(device);
1166         if (result)
1167                 goto end;
1168
1169         printk(KERN_INFO PREFIX "%s [%s] (gpe %d)\n",
1170                acpi_device_name(device), acpi_device_bid(device),
1171                (u32) ec->common.gpe_bit);
1172
1173         if (!first_ec)
1174                 first_ec = device;
1175
1176       end:
1177         if (result)
1178                 kfree(ec);
1179
1180         return_VALUE(result);
1181 }
1182
1183 static int acpi_ec_remove(struct acpi_device *device, int type)
1184 {
1185         union acpi_ec *ec = NULL;
1186
1187         ACPI_FUNCTION_TRACE("acpi_ec_remove");
1188
1189         if (!device)
1190                 return_VALUE(-EINVAL);
1191
1192         ec = acpi_driver_data(device);
1193
1194         acpi_ec_remove_fs(device);
1195
1196         kfree(ec);
1197
1198         return_VALUE(0);
1199 }
1200
1201 static acpi_status
1202 acpi_ec_io_ports(struct acpi_resource *resource, void *context)
1203 {
1204         union acpi_ec *ec = (union acpi_ec *)context;
1205         struct acpi_generic_address *addr;
1206
1207         if (resource->id != ACPI_RSTYPE_IO) {
1208                 return AE_OK;
1209         }
1210
1211         /*
1212          * The first address region returned is the data port, and
1213          * the second address region returned is the status/command
1214          * port.
1215          */
1216         if (ec->common.data_addr.register_bit_width == 0) {
1217                 addr = &ec->common.data_addr;
1218         } else if (ec->common.command_addr.register_bit_width == 0) {
1219                 addr = &ec->common.command_addr;
1220         } else {
1221                 return AE_CTRL_TERMINATE;
1222         }
1223
1224         addr->address_space_id = ACPI_ADR_SPACE_SYSTEM_IO;
1225         addr->register_bit_width = 8;
1226         addr->register_bit_offset = 0;
1227         addr->address = resource->data.io.min_base_address;
1228
1229         return AE_OK;
1230 }
1231
1232 static int acpi_ec_start(struct acpi_device *device)
1233 {
1234         acpi_status status = AE_OK;
1235         union acpi_ec *ec = NULL;
1236
1237         ACPI_FUNCTION_TRACE("acpi_ec_start");
1238
1239         if (!device)
1240                 return_VALUE(-EINVAL);
1241
1242         ec = acpi_driver_data(device);
1243
1244         if (!ec)
1245                 return_VALUE(-EINVAL);
1246
1247         /*
1248          * Get I/O port addresses. Convert to GAS format.
1249          */
1250         status = acpi_walk_resources(ec->common.handle, METHOD_NAME__CRS,
1251                                      acpi_ec_io_ports, ec);
1252         if (ACPI_FAILURE(status)
1253             || ec->common.command_addr.register_bit_width == 0) {
1254                 ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
1255                                   "Error getting I/O port addresses"));
1256                 return_VALUE(-ENODEV);
1257         }
1258
1259         ec->common.status_addr = ec->common.command_addr;
1260
1261         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "gpe=0x%02x, ports=0x%2x,0x%2x\n",
1262                           (u32) ec->common.gpe_bit,
1263                           (u32) ec->common.command_addr.address,
1264                           (u32) ec->common.data_addr.address));
1265
1266         /*
1267          * Install GPE handler
1268          */
1269         status = acpi_install_gpe_handler(NULL, ec->common.gpe_bit,
1270                                           ACPI_GPE_EDGE_TRIGGERED,
1271                                           &acpi_ec_gpe_handler, ec);
1272         if (ACPI_FAILURE(status)) {
1273                 return_VALUE(-ENODEV);
1274         }
1275         acpi_set_gpe_type(NULL, ec->common.gpe_bit, ACPI_GPE_TYPE_RUNTIME);
1276         acpi_enable_gpe(NULL, ec->common.gpe_bit, ACPI_NOT_ISR);
1277
1278         status = acpi_install_address_space_handler(ec->common.handle,
1279                                                     ACPI_ADR_SPACE_EC,
1280                                                     &acpi_ec_space_handler,
1281                                                     &acpi_ec_space_setup, ec);
1282         if (ACPI_FAILURE(status)) {
1283                 acpi_remove_gpe_handler(NULL, ec->common.gpe_bit,
1284                                         &acpi_ec_gpe_handler);
1285                 return_VALUE(-ENODEV);
1286         }
1287
1288         return_VALUE(AE_OK);
1289 }
1290
1291 static int acpi_ec_stop(struct acpi_device *device, int type)
1292 {
1293         acpi_status status = AE_OK;
1294         union acpi_ec *ec = NULL;
1295
1296         ACPI_FUNCTION_TRACE("acpi_ec_stop");
1297
1298         if (!device)
1299                 return_VALUE(-EINVAL);
1300
1301         ec = acpi_driver_data(device);
1302
1303         status = acpi_remove_address_space_handler(ec->common.handle,
1304                                                    ACPI_ADR_SPACE_EC,
1305                                                    &acpi_ec_space_handler);
1306         if (ACPI_FAILURE(status))
1307                 return_VALUE(-ENODEV);
1308
1309         status =
1310             acpi_remove_gpe_handler(NULL, ec->common.gpe_bit,
1311                                     &acpi_ec_gpe_handler);
1312         if (ACPI_FAILURE(status))
1313                 return_VALUE(-ENODEV);
1314
1315         return_VALUE(0);
1316 }
1317
1318 static acpi_status __init
1319 acpi_fake_ecdt_callback(acpi_handle handle,
1320                         u32 Level, void *context, void **retval)
1321 {
1322
1323         if (acpi_ec_polling_mode)
1324                 return acpi_fake_ecdt_polling_callback(handle,
1325                                                        Level, context, retval);
1326         else
1327                 return acpi_fake_ecdt_burst_callback(handle,
1328                                                      Level, context, retval);
1329 }
1330
1331 static acpi_status __init
1332 acpi_fake_ecdt_polling_callback(acpi_handle handle,
1333                                 u32 Level, void *context, void **retval)
1334 {
1335         acpi_status status;
1336
1337         status = acpi_walk_resources(handle, METHOD_NAME__CRS,
1338                                      acpi_ec_io_ports, ec_ecdt);
1339         if (ACPI_FAILURE(status))
1340                 return status;
1341         ec_ecdt->common.status_addr = ec_ecdt->common.command_addr;
1342
1343         ec_ecdt->common.uid = -1;
1344         acpi_evaluate_integer(handle, "_UID", NULL, &ec_ecdt->common.uid);
1345
1346         status =
1347             acpi_evaluate_integer(handle, "_GPE", NULL,
1348                                   &ec_ecdt->common.gpe_bit);
1349         if (ACPI_FAILURE(status))
1350                 return status;
1351         spin_lock_init(&ec_ecdt->polling.lock);
1352         ec_ecdt->common.global_lock = TRUE;
1353         ec_ecdt->common.handle = handle;
1354
1355         printk(KERN_INFO PREFIX "GPE=0x%02x, ports=0x%2x, 0x%2x\n",
1356                (u32) ec_ecdt->common.gpe_bit,
1357                (u32) ec_ecdt->common.command_addr.address,
1358                (u32) ec_ecdt->common.data_addr.address);
1359
1360         return AE_CTRL_TERMINATE;
1361 }
1362
1363 static acpi_status __init
1364 acpi_fake_ecdt_burst_callback(acpi_handle handle,
1365                               u32 Level, void *context, void **retval)
1366 {
1367         acpi_status status;
1368
1369         init_MUTEX(&ec_ecdt->burst.sem);
1370         init_waitqueue_head(&ec_ecdt->burst.wait);
1371         status = acpi_walk_resources(handle, METHOD_NAME__CRS,
1372                                      acpi_ec_io_ports, ec_ecdt);
1373         if (ACPI_FAILURE(status))
1374                 return status;
1375         ec_ecdt->common.status_addr = ec_ecdt->common.command_addr;
1376
1377         ec_ecdt->common.uid = -1;
1378         acpi_evaluate_integer(handle, "_UID", NULL, &ec_ecdt->common.uid);
1379
1380         status =
1381             acpi_evaluate_integer(handle, "_GPE", NULL,
1382                                   &ec_ecdt->common.gpe_bit);
1383         if (ACPI_FAILURE(status))
1384                 return status;
1385         ec_ecdt->common.global_lock = TRUE;
1386         ec_ecdt->common.handle = handle;
1387
1388         printk(KERN_INFO PREFIX "GPE=0x%02x, ports=0x%2x, 0x%2x\n",
1389                (u32) ec_ecdt->common.gpe_bit,
1390                (u32) ec_ecdt->common.command_addr.address,
1391                (u32) ec_ecdt->common.data_addr.address);
1392
1393         return AE_CTRL_TERMINATE;
1394 }
1395
1396 /*
1397  * Some BIOS (such as some from Gateway laptops) access EC region very early
1398  * such as in BAT0._INI or EC._INI before an EC device is found and
1399  * do not provide an ECDT. According to ACPI spec, ECDT isn't mandatorily
1400  * required, but if EC regison is accessed early, it is required.
1401  * The routine tries to workaround the BIOS bug by pre-scan EC device
1402  * It assumes that _CRS, _HID, _GPE, _UID methods of EC don't touch any
1403  * op region (since _REG isn't invoked yet). The assumption is true for
1404  * all systems found.
1405  */
1406 static int __init acpi_ec_fake_ecdt(void)
1407 {
1408         acpi_status status;
1409         int ret = 0;
1410
1411         printk(KERN_INFO PREFIX "Try to make an fake ECDT\n");
1412
1413         ec_ecdt = kmalloc(sizeof(union acpi_ec), GFP_KERNEL);
1414         if (!ec_ecdt) {
1415                 ret = -ENOMEM;
1416                 goto error;
1417         }
1418         memset(ec_ecdt, 0, sizeof(union acpi_ec));
1419
1420         status = acpi_get_devices(ACPI_EC_HID,
1421                                   acpi_fake_ecdt_callback, NULL, NULL);
1422         if (ACPI_FAILURE(status)) {
1423                 kfree(ec_ecdt);
1424                 ec_ecdt = NULL;
1425                 ret = -ENODEV;
1426                 goto error;
1427         }
1428         return 0;
1429       error:
1430         printk(KERN_ERR PREFIX "Can't make an fake ECDT\n");
1431         return ret;
1432 }
1433
1434 static int __init acpi_ec_get_real_ecdt(void)
1435 {
1436         if (acpi_ec_polling_mode)
1437                 return acpi_ec_polling_get_real_ecdt();
1438         else
1439                 return acpi_ec_burst_get_real_ecdt();
1440 }
1441
1442 static int __init acpi_ec_polling_get_real_ecdt(void)
1443 {
1444         acpi_status status;
1445         struct acpi_table_ecdt *ecdt_ptr;
1446
1447         status = acpi_get_firmware_table("ECDT", 1, ACPI_LOGICAL_ADDRESSING,
1448                                          (struct acpi_table_header **)
1449                                          &ecdt_ptr);
1450         if (ACPI_FAILURE(status))
1451                 return -ENODEV;
1452
1453         printk(KERN_INFO PREFIX "Found ECDT\n");
1454
1455         /*
1456          * Generate a temporary ec context to use until the namespace is scanned
1457          */
1458         ec_ecdt = kmalloc(sizeof(union acpi_ec), GFP_KERNEL);
1459         if (!ec_ecdt)
1460                 return -ENOMEM;
1461         memset(ec_ecdt, 0, sizeof(union acpi_ec));
1462
1463         ec_ecdt->common.command_addr = ecdt_ptr->ec_control;
1464         ec_ecdt->common.status_addr = ecdt_ptr->ec_control;
1465         ec_ecdt->common.data_addr = ecdt_ptr->ec_data;
1466         ec_ecdt->common.gpe_bit = ecdt_ptr->gpe_bit;
1467         spin_lock_init(&ec_ecdt->polling.lock);
1468         /* use the GL just to be safe */
1469         ec_ecdt->common.global_lock = TRUE;
1470         ec_ecdt->common.uid = ecdt_ptr->uid;
1471
1472         status =
1473             acpi_get_handle(NULL, ecdt_ptr->ec_id, &ec_ecdt->common.handle);
1474         if (ACPI_FAILURE(status)) {
1475                 goto error;
1476         }
1477
1478         return 0;
1479       error:
1480         printk(KERN_ERR PREFIX "Could not use ECDT\n");
1481         kfree(ec_ecdt);
1482         ec_ecdt = NULL;
1483
1484         return -ENODEV;
1485 }
1486
1487 static int __init acpi_ec_burst_get_real_ecdt(void)
1488 {
1489         acpi_status status;
1490         struct acpi_table_ecdt *ecdt_ptr;
1491
1492         status = acpi_get_firmware_table("ECDT", 1, ACPI_LOGICAL_ADDRESSING,
1493                                          (struct acpi_table_header **)
1494                                          &ecdt_ptr);
1495         if (ACPI_FAILURE(status))
1496                 return -ENODEV;
1497
1498         printk(KERN_INFO PREFIX "Found ECDT\n");
1499
1500         /*
1501          * Generate a temporary ec context to use until the namespace is scanned
1502          */
1503         ec_ecdt = kmalloc(sizeof(union acpi_ec), GFP_KERNEL);
1504         if (!ec_ecdt)
1505                 return -ENOMEM;
1506         memset(ec_ecdt, 0, sizeof(union acpi_ec));
1507
1508         init_MUTEX(&ec_ecdt->burst.sem);
1509         init_waitqueue_head(&ec_ecdt->burst.wait);
1510         ec_ecdt->common.command_addr = ecdt_ptr->ec_control;
1511         ec_ecdt->common.status_addr = ecdt_ptr->ec_control;
1512         ec_ecdt->common.data_addr = ecdt_ptr->ec_data;
1513         ec_ecdt->common.gpe_bit = ecdt_ptr->gpe_bit;
1514         /* use the GL just to be safe */
1515         ec_ecdt->common.global_lock = TRUE;
1516         ec_ecdt->common.uid = ecdt_ptr->uid;
1517
1518         status =
1519             acpi_get_handle(NULL, ecdt_ptr->ec_id, &ec_ecdt->common.handle);
1520         if (ACPI_FAILURE(status)) {
1521                 goto error;
1522         }
1523
1524         return 0;
1525       error:
1526         printk(KERN_ERR PREFIX "Could not use ECDT\n");
1527         kfree(ec_ecdt);
1528         ec_ecdt = NULL;
1529
1530         return -ENODEV;
1531 }
1532
1533 static int __initdata acpi_fake_ecdt_enabled;
1534 int __init acpi_ec_ecdt_probe(void)
1535 {
1536         acpi_status status;
1537         int ret;
1538
1539         ret = acpi_ec_get_real_ecdt();
1540         /* Try to make a fake ECDT */
1541         if (ret && acpi_fake_ecdt_enabled) {
1542                 ret = acpi_ec_fake_ecdt();
1543         }
1544
1545         if (ret)
1546                 return 0;
1547
1548         /*
1549          * Install GPE handler
1550          */
1551         status = acpi_install_gpe_handler(NULL, ec_ecdt->common.gpe_bit,
1552                                           ACPI_GPE_EDGE_TRIGGERED,
1553                                           &acpi_ec_gpe_handler, ec_ecdt);
1554         if (ACPI_FAILURE(status)) {
1555                 goto error;
1556         }
1557         acpi_set_gpe_type(NULL, ec_ecdt->common.gpe_bit, ACPI_GPE_TYPE_RUNTIME);
1558         acpi_enable_gpe(NULL, ec_ecdt->common.gpe_bit, ACPI_NOT_ISR);
1559
1560         status = acpi_install_address_space_handler(ACPI_ROOT_OBJECT,
1561                                                     ACPI_ADR_SPACE_EC,
1562                                                     &acpi_ec_space_handler,
1563                                                     &acpi_ec_space_setup,
1564                                                     ec_ecdt);
1565         if (ACPI_FAILURE(status)) {
1566                 acpi_remove_gpe_handler(NULL, ec_ecdt->common.gpe_bit,
1567                                         &acpi_ec_gpe_handler);
1568                 goto error;
1569         }
1570
1571         return 0;
1572
1573       error:
1574         printk(KERN_ERR PREFIX "Could not use ECDT\n");
1575         kfree(ec_ecdt);
1576         ec_ecdt = NULL;
1577
1578         return -ENODEV;
1579 }
1580
1581 static int __init acpi_ec_init(void)
1582 {
1583         int result = 0;
1584
1585         ACPI_FUNCTION_TRACE("acpi_ec_init");
1586
1587         if (acpi_disabled)
1588                 return_VALUE(0);
1589
1590         acpi_ec_dir = proc_mkdir(ACPI_EC_CLASS, acpi_root_dir);
1591         if (!acpi_ec_dir)
1592                 return_VALUE(-ENODEV);
1593
1594         /* Now register the driver for the EC */
1595         result = acpi_bus_register_driver(&acpi_ec_driver);
1596         if (result < 0) {
1597                 remove_proc_entry(ACPI_EC_CLASS, acpi_root_dir);
1598                 return_VALUE(-ENODEV);
1599         }
1600
1601         return_VALUE(result);
1602 }
1603
1604 subsys_initcall(acpi_ec_init);
1605
1606 /* EC driver currently not unloadable */
1607 #if 0
1608 static void __exit acpi_ec_exit(void)
1609 {
1610         ACPI_FUNCTION_TRACE("acpi_ec_exit");
1611
1612         acpi_bus_unregister_driver(&acpi_ec_driver);
1613
1614         remove_proc_entry(ACPI_EC_CLASS, acpi_root_dir);
1615
1616         return_VOID;
1617 }
1618 #endif                          /* 0 */
1619
1620 static int __init acpi_fake_ecdt_setup(char *str)
1621 {
1622         acpi_fake_ecdt_enabled = 1;
1623         return 0;
1624 }
1625
1626 __setup("acpi_fake_ecdt", acpi_fake_ecdt_setup);
1627 static int __init acpi_ec_set_polling_mode(char *str)
1628 {
1629         int burst;
1630
1631         if (!get_option(&str, &burst))
1632                 return 0;
1633
1634         if (burst) {
1635                 acpi_ec_polling_mode = EC_BURST;
1636                 acpi_ec_driver.ops.add = acpi_ec_burst_add;
1637         } else {
1638                 acpi_ec_polling_mode = EC_POLLING;
1639                 acpi_ec_driver.ops.add = acpi_ec_polling_add;
1640         }
1641         printk(KERN_INFO PREFIX "EC %s mode.\n", burst ? "burst" : "polling");
1642         return 0;
1643 }
1644
1645 __setup("ec_burst=", acpi_ec_set_polling_mode);