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   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_POLL                 0xFF
  64 #define EC_INTR                 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_intr_add(struct acpi_device *device);
  69 static int acpi_ec_poll_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_intr_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         } intr;
 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                 struct semaphore sem;
 120         } poll;
 121 };
 122
 123 static int acpi_ec_poll_wait(union acpi_ec *ec, u8 event);
 124 static int acpi_ec_intr_wait(union acpi_ec *ec, unsigned int event);
 125 static int acpi_ec_poll_read(union acpi_ec *ec, u8 address, u32 * data);
 126 static int acpi_ec_intr_read(union acpi_ec *ec, u8 address, u32 * data);
 127 static int acpi_ec_poll_write(union acpi_ec *ec, u8 address, u8 data);
 128 static int acpi_ec_intr_write(union acpi_ec *ec, u8 address, u8 data);
 129 static int acpi_ec_poll_query(union acpi_ec *ec, u32 * data);
 130 static int acpi_ec_intr_query(union acpi_ec *ec, u32 * data);
 131 static void acpi_ec_gpe_poll_query(void *ec_cxt);
 132 static void acpi_ec_gpe_intr_query(void *ec_cxt);
 133 static u32 acpi_ec_gpe_poll_handler(void *data);
 134 static u32 acpi_ec_gpe_intr_handler(void *data);
 135 static acpi_status __init
 136 acpi_fake_ecdt_poll_callback(acpi_handle handle,
 137                                 u32 Level, void *context, void **retval);
 138
 139 static acpi_status __init
 140 acpi_fake_ecdt_intr_callback(acpi_handle handle,
 141                               u32 Level, void *context, void **retval);
 142
 143 static int __init acpi_ec_poll_get_real_ecdt(void);
 144 static int __init acpi_ec_intr_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_poll_mode = EC_INTR;
 151
 152 /* --------------------------------------------------------------------------
 153                              Transaction Management
 154    -------------------------------------------------------------------------- */
 155
 156 static 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_poll_mode)
 167                 return acpi_ec_poll_wait(ec, event);
 168         else
 169                 return acpi_ec_intr_wait(ec, event);
 170 }
 171
 172 static int acpi_ec_poll_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_intr_wait(union acpi_ec *ec, unsigned int event)
 207 {
 208         int result = 0;
 209
 210         ACPI_FUNCTION_TRACE("acpi_ec_wait");
 211
 212         ec->intr.expect_event = event;
 213         smp_mb();
 214
 215         switch (event) {
 216         case ACPI_EC_EVENT_IBE:
 217                 if (~acpi_ec_read_status(ec) & event) {
 218                         ec->intr.expect_event = 0;
 219                         return_VALUE(0);
 220                 }
 221                 break;
 222         default:
 223                 break;
 224         }
 225
 226         result = wait_event_timeout(ec->intr.wait,
 227                                     !ec->intr.expect_event,
 228                                     msecs_to_jiffies(ACPI_EC_DELAY));
 229
 230         ec->intr.expect_event = 0;
 231         smp_mb();
 232
 233         /*
 234          * Verify that the event in question has actually happened by
 235          * querying EC status. Do the check even if operation timed-out
 236          * to make sure that we did not miss interrupt.
 237          */
 238         switch (event) {
 239         case ACPI_EC_EVENT_OBF:
 240                 if (acpi_ec_read_status(ec) & ACPI_EC_FLAG_OBF)
 241                         return_VALUE(0);
 242                 break;
 243
 244         case ACPI_EC_EVENT_IBE:
 245                 if (~acpi_ec_read_status(ec) & ACPI_EC_FLAG_IBF)
 246                         return_VALUE(0);
 247                 break;
 248         }
 249
 250         return_VALUE(-ETIME);
 251 }
 252
 253 #ifdef ACPI_FUTURE_USAGE
 254 /*
 255  * Note: samsung nv5000 doesn't work with ec burst mode.
 256  * http://bugzilla.kernel.org/show_bug.cgi?id=4980
 257  */
 258 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                 acpi_hw_low_level_read(8, &tmp, &ec->common.data_addr);
 274                 if (tmp != 0x90) {      /* Burst ACK byte */
 275                         return_VALUE(-EINVAL);
 276                 }
 277         }
 278
 279         atomic_set(&ec->intr.leaving_burst, 0);
 280         return_VALUE(0);
 281       end:
 282         printk(KERN_WARNING PREFIX "Error in acpi_ec_wait\n");
 283         return_VALUE(-1);
 284 }
 285
 286 int acpi_ec_leave_burst_mode(union acpi_ec *ec)
 287 {
 288         int status = 0;
 289
 290         ACPI_FUNCTION_TRACE("acpi_ec_leave_burst_mode");
 291
 292         status = acpi_ec_read_status(ec);
 293         if (status != -EINVAL && (status & ACPI_EC_FLAG_BURST)){
 294                 status = acpi_ec_wait(ec, ACPI_EC_FLAG_IBF);
 295                 if(status)
 296                         goto end;
 297                 acpi_hw_low_level_write(8, ACPI_EC_BURST_DISABLE, &ec->common.command_addr);
 298                 acpi_ec_wait(ec, ACPI_EC_FLAG_IBF);
 299         }
 300         atomic_set(&ec->intr.leaving_burst, 1);
 301         return_VALUE(0);
 302 end:
 303         printk(KERN_WARNING PREFIX "leave burst_mode:error\n");
 304         return_VALUE(-1);
 305 }
 306 #endif /* ACPI_FUTURE_USAGE */
 307
 308 static int acpi_ec_read(union acpi_ec *ec, u8 address, u32 * data)
 309 {
 310         if (acpi_ec_poll_mode)
 311                 return acpi_ec_poll_read(ec, address, data);
 312         else
 313                 return acpi_ec_intr_read(ec, address, data);
 314 }
 315 static int acpi_ec_write(union acpi_ec *ec, u8 address, u8 data)
 316 {
 317         if (acpi_ec_poll_mode)
 318                 return acpi_ec_poll_write(ec, address, data);
 319         else
 320                 return acpi_ec_intr_write(ec, address, data);
 321 }
 322 static int acpi_ec_poll_read(union acpi_ec *ec, u8 address, u32 * data)
 323 {
 324         acpi_status status = AE_OK;
 325         int result = 0;
 326         u32 glk = 0;
 327
 328         ACPI_FUNCTION_TRACE("acpi_ec_read");
 329
 330         if (!ec || !data)
 331                 return_VALUE(-EINVAL);
 332
 333         *data = 0;
 334
 335         if (ec->common.global_lock) {
 336                 status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk);
 337                 if (ACPI_FAILURE(status))
 338                         return_VALUE(-ENODEV);
 339         }
 340
 341         if (down_interruptible(&ec->poll.sem)) {
 342                 result = -ERESTARTSYS;
 343                 goto end_nosem;
 344         }
 345
 346         acpi_hw_low_level_write(8, ACPI_EC_COMMAND_READ,
 347                                 &ec->common.command_addr);
 348         result = acpi_ec_wait(ec, ACPI_EC_EVENT_IBE);
 349         if (result)
 350                 goto end;
 351
 352         acpi_hw_low_level_write(8, address, &ec->common.data_addr);
 353         result = acpi_ec_wait(ec, ACPI_EC_EVENT_OBF);
 354         if (result)
 355                 goto end;
 356
 357         acpi_hw_low_level_read(8, data, &ec->common.data_addr);
 358
 359         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Read [%02x] from address [%02x]\n",
 360                           *data, address));
 361
 362       end:
 363         up(&ec->poll.sem);
 364 end_nosem:
 365         if (ec->common.global_lock)
 366                 acpi_release_global_lock(glk);
 367
 368         return_VALUE(result);
 369 }
 370
 371 static int acpi_ec_poll_write(union acpi_ec *ec, u8 address, u8 data)
 372 {
 373         int result = 0;
 374         acpi_status status = AE_OK;
 375         u32 glk = 0;
 376
 377         ACPI_FUNCTION_TRACE("acpi_ec_write");
 378
 379         if (!ec)
 380                 return_VALUE(-EINVAL);
 381
 382         if (ec->common.global_lock) {
 383                 status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk);
 384                 if (ACPI_FAILURE(status))
 385                         return_VALUE(-ENODEV);
 386         }
 387
 388         if (down_interruptible(&ec->poll.sem)) {
 389                 result = -ERESTARTSYS;
 390                 goto end_nosem;
 391         }
 392
 393         acpi_hw_low_level_write(8, ACPI_EC_COMMAND_WRITE,
 394                                 &ec->common.command_addr);
 395         result = acpi_ec_wait(ec, ACPI_EC_EVENT_IBE);
 396         if (result)
 397                 goto end;
 398
 399         acpi_hw_low_level_write(8, address, &ec->common.data_addr);
 400         result = acpi_ec_wait(ec, ACPI_EC_EVENT_IBE);
 401         if (result)
 402                 goto end;
 403
 404         acpi_hw_low_level_write(8, data, &ec->common.data_addr);
 405         result = acpi_ec_wait(ec, ACPI_EC_EVENT_IBE);
 406         if (result)
 407                 goto end;
 408
 409         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Wrote [%02x] to address [%02x]\n",
 410                           data, address));
 411
 412       end:
 413         up(&ec->poll.sem);
 414 end_nosem:
 415         if (ec->common.global_lock)
 416                 acpi_release_global_lock(glk);
 417
 418         return_VALUE(result);
 419 }
 420
 421 static int acpi_ec_intr_read(union acpi_ec *ec, u8 address, u32 * data)
 422 {
 423         int status = 0;
 424         u32 glk;
 425
 426         ACPI_FUNCTION_TRACE("acpi_ec_read");
 427
 428         if (!ec || !data)
 429                 return_VALUE(-EINVAL);
 430
 431         *data = 0;
 432
 433         if (ec->common.global_lock) {
 434                 status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk);
 435                 if (ACPI_FAILURE(status))
 436                         return_VALUE(-ENODEV);
 437         }
 438
 439         WARN_ON(in_interrupt());
 440         down(&ec->intr.sem);
 441
 442         status = acpi_ec_wait(ec, ACPI_EC_EVENT_IBE);
 443         if (status) {
 444                 printk(KERN_DEBUG PREFIX "read EC, IB not empty\n");
 445                 goto end;
 446         }
 447         acpi_hw_low_level_write(8, ACPI_EC_COMMAND_READ,
 448                                 &ec->common.command_addr);
 449         status = acpi_ec_wait(ec, ACPI_EC_EVENT_IBE);
 450         if (status) {
 451                 printk(KERN_DEBUG PREFIX "read EC, IB not empty\n");
 452         }
 453
 454         acpi_hw_low_level_write(8, address, &ec->common.data_addr);
 455         status = acpi_ec_wait(ec, ACPI_EC_EVENT_OBF);
 456         if (status) {
 457                 printk(KERN_DEBUG PREFIX "read EC, OB not full\n");
 458                 goto end;
 459         }
 460         acpi_hw_low_level_read(8, data, &ec->common.data_addr);
 461         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Read [%02x] from address [%02x]\n",
 462                           *data, address));
 463
 464       end:
 465         up(&ec->intr.sem);
 466
 467         if (ec->common.global_lock)
 468                 acpi_release_global_lock(glk);
 469
 470         return_VALUE(status);
 471 }
 472
 473 static int acpi_ec_intr_write(union acpi_ec *ec, u8 address, u8 data)
 474 {
 475         int status = 0;
 476         u32 glk;
 477
 478         ACPI_FUNCTION_TRACE("acpi_ec_write");
 479
 480         if (!ec)
 481                 return_VALUE(-EINVAL);
 482
 483         if (ec->common.global_lock) {
 484                 status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk);
 485                 if (ACPI_FAILURE(status))
 486                         return_VALUE(-ENODEV);
 487         }
 488
 489         WARN_ON(in_interrupt());
 490         down(&ec->intr.sem);
 491
 492         status = acpi_ec_wait(ec, ACPI_EC_EVENT_IBE);
 493         if (status) {
 494                 printk(KERN_DEBUG PREFIX "write EC, IB not empty\n");
 495         }
 496         acpi_hw_low_level_write(8, ACPI_EC_COMMAND_WRITE,
 497                                 &ec->common.command_addr);
 498         status = acpi_ec_wait(ec, ACPI_EC_EVENT_IBE);
 499         if (status) {
 500                 printk(KERN_DEBUG PREFIX "write EC, IB not empty\n");
 501         }
 502
 503         acpi_hw_low_level_write(8, address, &ec->common.data_addr);
 504         status = acpi_ec_wait(ec, ACPI_EC_EVENT_IBE);
 505         if (status) {
 506                 printk(KERN_DEBUG PREFIX "write EC, IB not empty\n");
 507         }
 508
 509         acpi_hw_low_level_write(8, data, &ec->common.data_addr);
 510
 511         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Wrote [%02x] to address [%02x]\n",
 512                           data, address));
 513
 514         up(&ec->intr.sem);
 515
 516         if (ec->common.global_lock)
 517                 acpi_release_global_lock(glk);
 518
 519         return_VALUE(status);
 520 }
 521
 522 /*
 523  * Externally callable EC access functions. For now, assume 1 EC only
 524  */
 525 int ec_read(u8 addr, u8 * val)
 526 {
 527         union acpi_ec *ec;
 528         int err;
 529         u32 temp_data;
 530
 531         if (!first_ec)
 532                 return -ENODEV;
 533
 534         ec = acpi_driver_data(first_ec);
 535
 536         err = acpi_ec_read(ec, addr, &temp_data);
 537
 538         if (!err) {
 539                 *val = temp_data;
 540                 return 0;
 541         } else
 542                 return err;
 543 }
 544
 545 EXPORT_SYMBOL(ec_read);
 546
 547 int ec_write(u8 addr, u8 val)
 548 {
 549         union acpi_ec *ec;
 550         int err;
 551
 552         if (!first_ec)
 553                 return -ENODEV;
 554
 555         ec = acpi_driver_data(first_ec);
 556
 557         err = acpi_ec_write(ec, addr, val);
 558
 559         return err;
 560 }
 561
 562 EXPORT_SYMBOL(ec_write);
 563
 564 static int acpi_ec_query(union acpi_ec *ec, u32 * data)
 565 {
 566         if (acpi_ec_poll_mode)
 567                 return acpi_ec_poll_query(ec, data);
 568         else
 569                 return acpi_ec_intr_query(ec, data);
 570 }
 571 static int acpi_ec_poll_query(union acpi_ec *ec, u32 * data)
 572 {
 573         int result = 0;
 574         acpi_status status = AE_OK;
 575         u32 glk = 0;
 576
 577         ACPI_FUNCTION_TRACE("acpi_ec_query");
 578
 579         if (!ec || !data)
 580                 return_VALUE(-EINVAL);
 581
 582         *data = 0;
 583
 584         if (ec->common.global_lock) {
 585                 status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk);
 586                 if (ACPI_FAILURE(status))
 587                         return_VALUE(-ENODEV);
 588         }
 589
 590         /*
 591          * Query the EC to find out which _Qxx method we need to evaluate.
 592          * Note that successful completion of the query causes the ACPI_EC_SCI
 593          * bit to be cleared (and thus clearing the interrupt source).
 594          */
 595         if (down_interruptible(&ec->poll.sem)) {
 596                 result = -ERESTARTSYS;
 597                 goto end_nosem;
 598         }
 599
 600         acpi_hw_low_level_write(8, ACPI_EC_COMMAND_QUERY,
 601                                 &ec->common.command_addr);
 602         result = acpi_ec_wait(ec, ACPI_EC_EVENT_OBF);
 603         if (result)
 604                 goto end;
 605
 606         acpi_hw_low_level_read(8, data, &ec->common.data_addr);
 607         if (!*data)
 608                 result = -ENODATA;
 609
 610       end:
 611         up(&ec->poll.sem);
 612 end_nosem:
 613         if (ec->common.global_lock)
 614                 acpi_release_global_lock(glk);
 615
 616         return_VALUE(result);
 617 }
 618 static int acpi_ec_intr_query(union acpi_ec *ec, u32 * data)
 619 {
 620         int status = 0;
 621         u32 glk;
 622
 623         ACPI_FUNCTION_TRACE("acpi_ec_query");
 624
 625         if (!ec || !data)
 626                 return_VALUE(-EINVAL);
 627         *data = 0;
 628
 629         if (ec->common.global_lock) {
 630                 status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk);
 631                 if (ACPI_FAILURE(status))
 632                         return_VALUE(-ENODEV);
 633         }
 634
 635         down(&ec->intr.sem);
 636
 637         status = acpi_ec_wait(ec, ACPI_EC_EVENT_IBE);
 638         if (status) {
 639                 printk(KERN_DEBUG PREFIX "query EC, IB not empty\n");
 640                 goto end;
 641         }
 642         /*
 643          * Query the EC to find out which _Qxx method we need to evaluate.
 644          * Note that successful completion of the query causes the ACPI_EC_SCI
 645          * bit to be cleared (and thus clearing the interrupt source).
 646          */
 647         acpi_hw_low_level_write(8, ACPI_EC_COMMAND_QUERY,
 648                                 &ec->common.command_addr);
 649         status = acpi_ec_wait(ec, ACPI_EC_EVENT_OBF);
 650         if (status) {
 651                 printk(KERN_DEBUG PREFIX "query EC, OB not full\n");
 652                 goto end;
 653         }
 654
 655         acpi_hw_low_level_read(8, data, &ec->common.data_addr);
 656         if (!*data)
 657                 status = -ENODATA;
 658
 659       end:
 660         up(&ec->intr.sem);
 661
 662         if (ec->common.global_lock)
 663                 acpi_release_global_lock(glk);
 664
 665         return_VALUE(status);
 666 }
 667
 668 /* --------------------------------------------------------------------------
 669                                 Event Management
 670    -------------------------------------------------------------------------- */
 671
 672 union acpi_ec_query_data {
 673         acpi_handle handle;
 674         u8 data;
 675 };
 676
 677 static void acpi_ec_gpe_query(void *ec_cxt)
 678 {
 679         if (acpi_ec_poll_mode)
 680                 acpi_ec_gpe_poll_query(ec_cxt);
 681         else
 682                 acpi_ec_gpe_intr_query(ec_cxt);
 683 }
 684
 685 static void acpi_ec_gpe_poll_query(void *ec_cxt)
 686 {
 687         union acpi_ec *ec = (union acpi_ec *)ec_cxt;
 688         u32 value = 0;
 689         static char object_name[5] = { '_', 'Q', '0', '0', '\0' };
 690         const char hex[] = { '0', '1', '2', '3', '4', '5', '6', '7',
 691                 '8', '9', 'A', 'B', 'C', 'D', 'E', 'F'
 692         };
 693
 694         ACPI_FUNCTION_TRACE("acpi_ec_gpe_query");
 695
 696         if (!ec_cxt)
 697                 goto end;
 698
 699         if (down_interruptible (&ec->poll.sem)) {
 700                 return_VOID;
 701         }
 702         acpi_hw_low_level_read(8, &value, &ec->common.command_addr);
 703         up(&ec->poll.sem);
 704
 705         /* TBD: Implement asynch events!
 706          * NOTE: All we care about are EC-SCI's.  Other EC events are
 707          * handled via polling (yuck!).  This is because some systems
 708          * treat EC-SCIs as level (versus EDGE!) triggered, preventing
 709          *  a purely interrupt-driven approach (grumble, grumble).
 710          */
 711         if (!(value & ACPI_EC_FLAG_SCI))
 712                 goto end;
 713
 714         if (acpi_ec_query(ec, &value))
 715                 goto end;
 716
 717         object_name[2] = hex[((value >> 4) & 0x0F)];
 718         object_name[3] = hex[(value & 0x0F)];
 719
 720         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Evaluating %s\n", object_name));
 721
 722         acpi_evaluate_object(ec->common.handle, object_name, NULL, NULL);
 723
 724       end:
 725         acpi_enable_gpe(NULL, ec->common.gpe_bit, ACPI_NOT_ISR);
 726 }
 727 static void acpi_ec_gpe_intr_query(void *ec_cxt)
 728 {
 729         union acpi_ec *ec = (union acpi_ec *)ec_cxt;
 730         u32 value;
 731         int result = -ENODATA;
 732         static char object_name[5] = { '_', 'Q', '0', '0', '\0' };
 733         const char hex[] = { '0', '1', '2', '3', '4', '5', '6', '7',
 734                 '8', '9', 'A', 'B', 'C', 'D', 'E', 'F'
 735         };
 736
 737         ACPI_FUNCTION_TRACE("acpi_ec_gpe_query");
 738
 739         if (acpi_ec_read_status(ec) & ACPI_EC_FLAG_SCI)
 740                 result = acpi_ec_query(ec, &value);
 741
 742         if (result)
 743                 goto end;
 744
 745         object_name[2] = hex[((value >> 4) & 0x0F)];
 746         object_name[3] = hex[(value & 0x0F)];
 747
 748         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Evaluating %s\n", object_name));
 749
 750         acpi_evaluate_object(ec->common.handle, object_name, NULL, NULL);
 751       end:
 752         atomic_dec(&ec->intr.pending_gpe);
 753         return;
 754 }
 755
 756 static u32 acpi_ec_gpe_handler(void *data)
 757 {
 758         if (acpi_ec_poll_mode)
 759                 return acpi_ec_gpe_poll_handler(data);
 760         else
 761                 return acpi_ec_gpe_intr_handler(data);
 762 }
 763 static u32 acpi_ec_gpe_poll_handler(void *data)
 764 {
 765         acpi_status status = AE_OK;
 766         union acpi_ec *ec = (union acpi_ec *)data;
 767
 768         if (!ec)
 769                 return ACPI_INTERRUPT_NOT_HANDLED;
 770
 771         acpi_disable_gpe(NULL, ec->common.gpe_bit, ACPI_ISR);
 772
 773         status = acpi_os_execute(OSL_EC_POLL_HANDLER, acpi_ec_gpe_query, ec);
 774
 775         if (status == AE_OK)
 776                 return ACPI_INTERRUPT_HANDLED;
 777         else
 778                 return ACPI_INTERRUPT_NOT_HANDLED;
 779 }
 780 static u32 acpi_ec_gpe_intr_handler(void *data)
 781 {
 782         acpi_status status = AE_OK;
 783         u32 value;
 784         union acpi_ec *ec = (union acpi_ec *)data;
 785
 786         if (!ec)
 787                 return ACPI_INTERRUPT_NOT_HANDLED;
 788
 789         acpi_clear_gpe(NULL, ec->common.gpe_bit, ACPI_ISR);
 790         value = acpi_ec_read_status(ec);
 791
 792         switch (ec->intr.expect_event) {
 793         case ACPI_EC_EVENT_OBF:
 794                 if (!(value & ACPI_EC_FLAG_OBF))
 795                         break;
 796         case ACPI_EC_EVENT_IBE:
 797                 if ((value & ACPI_EC_FLAG_IBF))
 798                         break;
 799                 ec->intr.expect_event = 0;
 800                 wake_up(&ec->intr.wait);
 801                 return ACPI_INTERRUPT_HANDLED;
 802         default:
 803                 break;
 804         }
 805
 806         if (value & ACPI_EC_FLAG_SCI) {
 807                 atomic_add(1, &ec->intr.pending_gpe);
 808                 status = acpi_os_execute(OSL_EC_BURST_HANDLER,
 809                                                      acpi_ec_gpe_query, ec);
 810                 return status == AE_OK ?
 811                     ACPI_INTERRUPT_HANDLED : ACPI_INTERRUPT_NOT_HANDLED;
 812         }
 813         acpi_enable_gpe(NULL, ec->common.gpe_bit, ACPI_ISR);
 814         return status == AE_OK ?
 815             ACPI_INTERRUPT_HANDLED : ACPI_INTERRUPT_NOT_HANDLED;
 816 }
 817
 818 /* --------------------------------------------------------------------------
 819                              Address Space Management
 820    -------------------------------------------------------------------------- */
 821
 822 static acpi_status
 823 acpi_ec_space_setup(acpi_handle region_handle,
 824                     u32 function, void *handler_context, void **return_context)
 825 {
 826         /*
 827          * The EC object is in the handler context and is needed
 828          * when calling the acpi_ec_space_handler.
 829          */
 830         *return_context = (function != ACPI_REGION_DEACTIVATE) ?
 831             handler_context : NULL;
 832
 833         return AE_OK;
 834 }
 835
 836 static acpi_status
 837 acpi_ec_space_handler(u32 function,
 838                       acpi_physical_address address,
 839                       u32 bit_width,
 840                       acpi_integer * value,
 841                       void *handler_context, void *region_context)
 842 {
 843         int result = 0;
 844         union acpi_ec *ec = NULL;
 845         u64 temp = *value;
 846         acpi_integer f_v = 0;
 847         int i = 0;
 848
 849         ACPI_FUNCTION_TRACE("acpi_ec_space_handler");
 850
 851         if ((address > 0xFF) || !value || !handler_context)
 852                 return_VALUE(AE_BAD_PARAMETER);
 853
 854         if (bit_width != 8 && acpi_strict) {
 855                 printk(KERN_WARNING PREFIX
 856                        "acpi_ec_space_handler: bit_width should be 8\n");
 857                 return_VALUE(AE_BAD_PARAMETER);
 858         }
 859
 860         ec = (union acpi_ec *)handler_context;
 861
 862       next_byte:
 863         switch (function) {
 864         case ACPI_READ:
 865                 temp = 0;
 866                 result = acpi_ec_read(ec, (u8) address, (u32 *) & temp);
 867                 break;
 868         case ACPI_WRITE:
 869                 result = acpi_ec_write(ec, (u8) address, (u8) temp);
 870                 break;
 871         default:
 872                 result = -EINVAL;
 873                 goto out;
 874                 break;
 875         }
 876
 877         bit_width -= 8;
 878         if (bit_width) {
 879                 if (function == ACPI_READ)
 880                         f_v |= temp << 8 * i;
 881                 if (function == ACPI_WRITE)
 882                         temp >>= 8;
 883                 i++;
 884                 address++;
 885                 goto next_byte;
 886         }
 887
 888         if (function == ACPI_READ) {
 889                 f_v |= temp << 8 * i;
 890                 *value = f_v;
 891         }
 892
 893       out:
 894         switch (result) {
 895         case -EINVAL:
 896                 return_VALUE(AE_BAD_PARAMETER);
 897                 break;
 898         case -ENODEV:
 899                 return_VALUE(AE_NOT_FOUND);
 900                 break;
 901         case -ETIME:
 902                 return_VALUE(AE_TIME);
 903                 break;
 904         default:
 905                 return_VALUE(AE_OK);
 906         }
 907 }
 908
 909 /* --------------------------------------------------------------------------
 910                               FS Interface (/proc)
 911    -------------------------------------------------------------------------- */
 912
 913 static struct proc_dir_entry *acpi_ec_dir;
 914
 915 static int acpi_ec_read_info(struct seq_file *seq, void *offset)
 916 {
 917         union acpi_ec *ec = (union acpi_ec *)seq->private;
 918
 919         ACPI_FUNCTION_TRACE("acpi_ec_read_info");
 920
 921         if (!ec)
 922                 goto end;
 923
 924         seq_printf(seq, "gpe bit:                 0x%02x\n",
 925                    (u32) ec->common.gpe_bit);
 926         seq_printf(seq, "ports:                   0x%02x, 0x%02x\n",
 927                    (u32) ec->common.status_addr.address,
 928                    (u32) ec->common.data_addr.address);
 929         seq_printf(seq, "use global lock:         %s\n",
 930                    ec->common.global_lock ? "yes" : "no");
 931         acpi_enable_gpe(NULL, ec->common.gpe_bit, ACPI_NOT_ISR);
 932
 933       end:
 934         return_VALUE(0);
 935 }
 936
 937 static int acpi_ec_info_open_fs(struct inode *inode, struct file *file)
 938 {
 939         return single_open(file, acpi_ec_read_info, PDE(inode)->data);
 940 }
 941
 942 static struct file_operations acpi_ec_info_ops = {
 943         .open = acpi_ec_info_open_fs,
 944         .read = seq_read,
 945         .llseek = seq_lseek,
 946         .release = single_release,
 947         .owner = THIS_MODULE,
 948 };
 949
 950 static int acpi_ec_add_fs(struct acpi_device *device)
 951 {
 952         struct proc_dir_entry *entry = NULL;
 953
 954         ACPI_FUNCTION_TRACE("acpi_ec_add_fs");
 955
 956         if (!acpi_device_dir(device)) {
 957                 acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device),
 958                                                      acpi_ec_dir);
 959                 if (!acpi_device_dir(device))
 960                         return_VALUE(-ENODEV);
 961         }
 962
 963         entry = create_proc_entry(ACPI_EC_FILE_INFO, S_IRUGO,
 964                                   acpi_device_dir(device));
 965         if (!entry)
 966                 ACPI_DEBUG_PRINT((ACPI_DB_WARN,
 967                                   "Unable to create '%s' fs entry\n",
 968                                   ACPI_EC_FILE_INFO));
 969         else {
 970                 entry->proc_fops = &acpi_ec_info_ops;
 971                 entry->data = acpi_driver_data(device);
 972                 entry->owner = THIS_MODULE;
 973         }
 974
 975         return_VALUE(0);
 976 }
 977
 978 static int acpi_ec_remove_fs(struct acpi_device *device)
 979 {
 980         ACPI_FUNCTION_TRACE("acpi_ec_remove_fs");
 981
 982         if (acpi_device_dir(device)) {
 983                 remove_proc_entry(ACPI_EC_FILE_INFO, acpi_device_dir(device));
 984                 remove_proc_entry(acpi_device_bid(device), acpi_ec_dir);
 985                 acpi_device_dir(device) = NULL;
 986         }
 987
 988         return_VALUE(0);
 989 }
 990
 991 /* --------------------------------------------------------------------------
 992                                Driver Interface
 993    -------------------------------------------------------------------------- */
 994
 995 static int acpi_ec_poll_add(struct acpi_device *device)
 996 {
 997         int result = 0;
 998         acpi_status status = AE_OK;
 999         union acpi_ec *ec = NULL;
1000
1001         ACPI_FUNCTION_TRACE("acpi_ec_add");
1002
1003         if (!device)
1004                 return_VALUE(-EINVAL);
1005
1006         ec = kmalloc(sizeof(union acpi_ec), GFP_KERNEL);
1007         if (!ec)
1008                 return_VALUE(-ENOMEM);
1009         memset(ec, 0, sizeof(union acpi_ec));
1010
1011         ec->common.handle = device->handle;
1012         ec->common.uid = -1;
1013         init_MUTEX(&ec->poll.sem);
1014         strcpy(acpi_device_name(device), ACPI_EC_DEVICE_NAME);
1015         strcpy(acpi_device_class(device), ACPI_EC_CLASS);
1016         acpi_driver_data(device) = ec;
1017
1018         /* Use the global lock for all EC transactions? */
1019         acpi_evaluate_integer(ec->common.handle, "_GLK", NULL,
1020                               &ec->common.global_lock);
1021
1022         /* XXX we don't test uids, because on some boxes ecdt uid = 0, see:
1023            http://bugzilla.kernel.org/show_bug.cgi?id=6111 */
1024         if (ec_ecdt) {
1025                 acpi_remove_address_space_handler(ACPI_ROOT_OBJECT,
1026                                                   ACPI_ADR_SPACE_EC,
1027                                                   &acpi_ec_space_handler);
1028
1029                 acpi_remove_gpe_handler(NULL, ec_ecdt->common.gpe_bit,
1030                                         &acpi_ec_gpe_handler);
1031
1032                 kfree(ec_ecdt);
1033         }
1034
1035         /* Get GPE bit assignment (EC events). */
1036         /* TODO: Add support for _GPE returning a package */
1037         status =
1038             acpi_evaluate_integer(ec->common.handle, "_GPE", NULL,
1039                                   &ec->common.gpe_bit);
1040         if (ACPI_FAILURE(status)) {
1041                 ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
1042                                   "Error obtaining GPE bit assignment\n"));
1043                 result = -ENODEV;
1044                 goto end;
1045         }
1046
1047         result = acpi_ec_add_fs(device);
1048         if (result)
1049                 goto end;
1050
1051         printk(KERN_INFO PREFIX "%s [%s] (gpe %d) polling mode.\n",
1052                acpi_device_name(device), acpi_device_bid(device),
1053                (u32) ec->common.gpe_bit);
1054
1055         if (!first_ec)
1056                 first_ec = device;
1057
1058       end:
1059         if (result)
1060                 kfree(ec);
1061
1062         return_VALUE(result);
1063 }
1064 static int acpi_ec_intr_add(struct acpi_device *device)
1065 {
1066         int result = 0;
1067         acpi_status status = AE_OK;
1068         union acpi_ec *ec = NULL;
1069
1070         ACPI_FUNCTION_TRACE("acpi_ec_add");
1071
1072         if (!device)
1073                 return_VALUE(-EINVAL);
1074
1075         ec = kmalloc(sizeof(union acpi_ec), GFP_KERNEL);
1076         if (!ec)
1077                 return_VALUE(-ENOMEM);
1078         memset(ec, 0, sizeof(union acpi_ec));
1079
1080         ec->common.handle = device->handle;
1081         ec->common.uid = -1;
1082         atomic_set(&ec->intr.pending_gpe, 0);
1083         atomic_set(&ec->intr.leaving_burst, 1);
1084         init_MUTEX(&ec->intr.sem);
1085         init_waitqueue_head(&ec->intr.wait);
1086         strcpy(acpi_device_name(device), ACPI_EC_DEVICE_NAME);
1087         strcpy(acpi_device_class(device), ACPI_EC_CLASS);
1088         acpi_driver_data(device) = ec;
1089
1090         /* Use the global lock for all EC transactions? */
1091         acpi_evaluate_integer(ec->common.handle, "_GLK", NULL,
1092                               &ec->common.global_lock);
1093
1094         /* XXX we don't test uids, because on some boxes ecdt uid = 0, see:
1095            http://bugzilla.kernel.org/show_bug.cgi?id=6111 */
1096         if (ec_ecdt) {
1097                 acpi_remove_address_space_handler(ACPI_ROOT_OBJECT,
1098                                                   ACPI_ADR_SPACE_EC,
1099                                                   &acpi_ec_space_handler);
1100
1101                 acpi_remove_gpe_handler(NULL, ec_ecdt->common.gpe_bit,
1102                                         &acpi_ec_gpe_handler);
1103
1104                 kfree(ec_ecdt);
1105         }
1106
1107         /* Get GPE bit assignment (EC events). */
1108         /* TODO: Add support for _GPE returning a package */
1109         status =
1110             acpi_evaluate_integer(ec->common.handle, "_GPE", NULL,
1111                                   &ec->common.gpe_bit);
1112         if (ACPI_FAILURE(status)) {
1113                 ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
1114                                   "Error obtaining GPE bit assignment\n"));
1115                 result = -ENODEV;
1116                 goto end;
1117         }
1118
1119         result = acpi_ec_add_fs(device);
1120         if (result)
1121                 goto end;
1122
1123         printk(KERN_INFO PREFIX "%s [%s] (gpe %d) interrupt mode.\n",
1124                acpi_device_name(device), acpi_device_bid(device),
1125                (u32) ec->common.gpe_bit);
1126
1127         if (!first_ec)
1128                 first_ec = device;
1129
1130       end:
1131         if (result)
1132                 kfree(ec);
1133
1134         return_VALUE(result);
1135 }
1136
1137 static int acpi_ec_remove(struct acpi_device *device, int type)
1138 {
1139         union acpi_ec *ec = NULL;
1140
1141         ACPI_FUNCTION_TRACE("acpi_ec_remove");
1142
1143         if (!device)
1144                 return_VALUE(-EINVAL);
1145
1146         ec = acpi_driver_data(device);
1147
1148         acpi_ec_remove_fs(device);
1149
1150         kfree(ec);
1151
1152         return_VALUE(0);
1153 }
1154
1155 static acpi_status
1156 acpi_ec_io_ports(struct acpi_resource *resource, void *context)
1157 {
1158         union acpi_ec *ec = (union acpi_ec *)context;
1159         struct acpi_generic_address *addr;
1160
1161         if (resource->type != ACPI_RESOURCE_TYPE_IO) {
1162                 return AE_OK;
1163         }
1164
1165         /*
1166          * The first address region returned is the data port, and
1167          * the second address region returned is the status/command
1168          * port.
1169          */
1170         if (ec->common.data_addr.register_bit_width == 0) {
1171                 addr = &ec->common.data_addr;
1172         } else if (ec->common.command_addr.register_bit_width == 0) {
1173                 addr = &ec->common.command_addr;
1174         } else {
1175                 return AE_CTRL_TERMINATE;
1176         }
1177
1178         addr->address_space_id = ACPI_ADR_SPACE_SYSTEM_IO;
1179         addr->register_bit_width = 8;
1180         addr->register_bit_offset = 0;
1181         addr->address = resource->data.io.minimum;
1182
1183         return AE_OK;
1184 }
1185
1186 static int acpi_ec_start(struct acpi_device *device)
1187 {
1188         acpi_status status = AE_OK;
1189         union acpi_ec *ec = NULL;
1190
1191         ACPI_FUNCTION_TRACE("acpi_ec_start");
1192
1193         if (!device)
1194                 return_VALUE(-EINVAL);
1195
1196         ec = acpi_driver_data(device);
1197
1198         if (!ec)
1199                 return_VALUE(-EINVAL);
1200
1201         /*
1202          * Get I/O port addresses. Convert to GAS format.
1203          */
1204         status = acpi_walk_resources(ec->common.handle, METHOD_NAME__CRS,
1205                                      acpi_ec_io_ports, ec);
1206         if (ACPI_FAILURE(status)
1207             || ec->common.command_addr.register_bit_width == 0) {
1208                 ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
1209                                   "Error getting I/O port addresses"));
1210                 return_VALUE(-ENODEV);
1211         }
1212
1213         ec->common.status_addr = ec->common.command_addr;
1214
1215         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "gpe=0x%02x, ports=0x%2x,0x%2x\n",
1216                           (u32) ec->common.gpe_bit,
1217                           (u32) ec->common.command_addr.address,
1218                           (u32) ec->common.data_addr.address));
1219
1220         /*
1221          * Install GPE handler
1222          */
1223         status = acpi_install_gpe_handler(NULL, ec->common.gpe_bit,
1224                                           ACPI_GPE_EDGE_TRIGGERED,
1225                                           &acpi_ec_gpe_handler, ec);
1226         if (ACPI_FAILURE(status)) {
1227                 return_VALUE(-ENODEV);
1228         }
1229         acpi_set_gpe_type(NULL, ec->common.gpe_bit, ACPI_GPE_TYPE_RUNTIME);
1230         acpi_enable_gpe(NULL, ec->common.gpe_bit, ACPI_NOT_ISR);
1231
1232         status = acpi_install_address_space_handler(ec->common.handle,
1233                                                     ACPI_ADR_SPACE_EC,
1234                                                     &acpi_ec_space_handler,
1235                                                     &acpi_ec_space_setup, ec);
1236         if (ACPI_FAILURE(status)) {
1237                 acpi_remove_gpe_handler(NULL, ec->common.gpe_bit,
1238                                         &acpi_ec_gpe_handler);
1239                 return_VALUE(-ENODEV);
1240         }
1241
1242         return_VALUE(AE_OK);
1243 }
1244
1245 static int acpi_ec_stop(struct acpi_device *device, int type)
1246 {
1247         acpi_status status = AE_OK;
1248         union acpi_ec *ec = NULL;
1249
1250         ACPI_FUNCTION_TRACE("acpi_ec_stop");
1251
1252         if (!device)
1253                 return_VALUE(-EINVAL);
1254
1255         ec = acpi_driver_data(device);
1256
1257         status = acpi_remove_address_space_handler(ec->common.handle,
1258                                                    ACPI_ADR_SPACE_EC,
1259                                                    &acpi_ec_space_handler);
1260         if (ACPI_FAILURE(status))
1261                 return_VALUE(-ENODEV);
1262
1263         status =
1264             acpi_remove_gpe_handler(NULL, ec->common.gpe_bit,
1265                                     &acpi_ec_gpe_handler);
1266         if (ACPI_FAILURE(status))
1267                 return_VALUE(-ENODEV);
1268
1269         return_VALUE(0);
1270 }
1271
1272 static acpi_status __init
1273 acpi_fake_ecdt_callback(acpi_handle handle,
1274                         u32 Level, void *context, void **retval)
1275 {
1276
1277         if (acpi_ec_poll_mode)
1278                 return acpi_fake_ecdt_poll_callback(handle,
1279                                                        Level, context, retval);
1280         else
1281                 return acpi_fake_ecdt_intr_callback(handle,
1282                                                      Level, context, retval);
1283 }
1284
1285 static acpi_status __init
1286 acpi_fake_ecdt_poll_callback(acpi_handle handle,
1287                                 u32 Level, void *context, void **retval)
1288 {
1289         acpi_status status;
1290
1291         status = acpi_walk_resources(handle, METHOD_NAME__CRS,
1292                                      acpi_ec_io_ports, ec_ecdt);
1293         if (ACPI_FAILURE(status))
1294                 return status;
1295         ec_ecdt->common.status_addr = ec_ecdt->common.command_addr;
1296
1297         ec_ecdt->common.uid = -1;
1298         acpi_evaluate_integer(handle, "_UID", NULL, &ec_ecdt->common.uid);
1299
1300         status =
1301             acpi_evaluate_integer(handle, "_GPE", NULL,
1302                                   &ec_ecdt->common.gpe_bit);
1303         if (ACPI_FAILURE(status))
1304                 return status;
1305         init_MUTEX(&ec_ecdt->poll.sem);
1306         ec_ecdt->common.global_lock = TRUE;
1307         ec_ecdt->common.handle = handle;
1308
1309         printk(KERN_INFO PREFIX "GPE=0x%02x, ports=0x%2x, 0x%2x\n",
1310                (u32) ec_ecdt->common.gpe_bit,
1311                (u32) ec_ecdt->common.command_addr.address,
1312                (u32) ec_ecdt->common.data_addr.address);
1313
1314         return AE_CTRL_TERMINATE;
1315 }
1316
1317 static acpi_status __init
1318 acpi_fake_ecdt_intr_callback(acpi_handle handle,
1319                               u32 Level, void *context, void **retval)
1320 {
1321         acpi_status status;
1322
1323         init_MUTEX(&ec_ecdt->intr.sem);
1324         init_waitqueue_head(&ec_ecdt->intr.wait);
1325         status = acpi_walk_resources(handle, METHOD_NAME__CRS,
1326                                      acpi_ec_io_ports, ec_ecdt);
1327         if (ACPI_FAILURE(status))
1328                 return status;
1329         ec_ecdt->common.status_addr = ec_ecdt->common.command_addr;
1330
1331         ec_ecdt->common.uid = -1;
1332         acpi_evaluate_integer(handle, "_UID", NULL, &ec_ecdt->common.uid);
1333
1334         status =
1335             acpi_evaluate_integer(handle, "_GPE", NULL,
1336                                   &ec_ecdt->common.gpe_bit);
1337         if (ACPI_FAILURE(status))
1338                 return status;
1339         ec_ecdt->common.global_lock = TRUE;
1340         ec_ecdt->common.handle = handle;
1341
1342         printk(KERN_INFO PREFIX "GPE=0x%02x, ports=0x%2x, 0x%2x\n",
1343                (u32) ec_ecdt->common.gpe_bit,
1344                (u32) ec_ecdt->common.command_addr.address,
1345                (u32) ec_ecdt->common.data_addr.address);
1346
1347         return AE_CTRL_TERMINATE;
1348 }
1349
1350 /*
1351  * Some BIOS (such as some from Gateway laptops) access EC region very early
1352  * such as in BAT0._INI or EC._INI before an EC device is found and
1353  * do not provide an ECDT. According to ACPI spec, ECDT isn't mandatorily
1354  * required, but if EC regison is accessed early, it is required.
1355  * The routine tries to workaround the BIOS bug by pre-scan EC device
1356  * It assumes that _CRS, _HID, _GPE, _UID methods of EC don't touch any
1357  * op region (since _REG isn't invoked yet). The assumption is true for
1358  * all systems found.
1359  */
1360 static int __init acpi_ec_fake_ecdt(void)
1361 {
1362         acpi_status status;
1363         int ret = 0;
1364
1365         printk(KERN_INFO PREFIX "Try to make an fake ECDT\n");
1366
1367         ec_ecdt = kmalloc(sizeof(union acpi_ec), GFP_KERNEL);
1368         if (!ec_ecdt) {
1369                 ret = -ENOMEM;
1370                 goto error;
1371         }
1372         memset(ec_ecdt, 0, sizeof(union acpi_ec));
1373
1374         status = acpi_get_devices(ACPI_EC_HID,
1375                                   acpi_fake_ecdt_callback, NULL, NULL);
1376         if (ACPI_FAILURE(status)) {
1377                 kfree(ec_ecdt);
1378                 ec_ecdt = NULL;
1379                 ret = -ENODEV;
1380                 goto error;
1381         }
1382         return 0;
1383       error:
1384         printk(KERN_ERR PREFIX "Can't make an fake ECDT\n");
1385         return ret;
1386 }
1387
1388 static int __init acpi_ec_get_real_ecdt(void)
1389 {
1390         if (acpi_ec_poll_mode)
1391                 return acpi_ec_poll_get_real_ecdt();
1392         else
1393                 return acpi_ec_intr_get_real_ecdt();
1394 }
1395
1396 static int __init acpi_ec_poll_get_real_ecdt(void)
1397 {
1398         acpi_status status;
1399         struct acpi_table_ecdt *ecdt_ptr;
1400
1401         status = acpi_get_firmware_table("ECDT", 1, ACPI_LOGICAL_ADDRESSING,
1402                                          (struct acpi_table_header **)
1403                                          &ecdt_ptr);
1404         if (ACPI_FAILURE(status))
1405                 return -ENODEV;
1406
1407         printk(KERN_INFO PREFIX "Found ECDT\n");
1408
1409         /*
1410          * Generate a temporary ec context to use until the namespace is scanned
1411          */
1412         ec_ecdt = kmalloc(sizeof(union acpi_ec), GFP_KERNEL);
1413         if (!ec_ecdt)
1414                 return -ENOMEM;
1415         memset(ec_ecdt, 0, sizeof(union acpi_ec));
1416
1417         ec_ecdt->common.command_addr = ecdt_ptr->ec_control;
1418         ec_ecdt->common.status_addr = ecdt_ptr->ec_control;
1419         ec_ecdt->common.data_addr = ecdt_ptr->ec_data;
1420         ec_ecdt->common.gpe_bit = ecdt_ptr->gpe_bit;
1421         init_MUTEX(&ec_ecdt->poll.sem);
1422         /* use the GL just to be safe */
1423         ec_ecdt->common.global_lock = TRUE;
1424         ec_ecdt->common.uid = ecdt_ptr->uid;
1425
1426         status =
1427             acpi_get_handle(NULL, ecdt_ptr->ec_id, &ec_ecdt->common.handle);
1428         if (ACPI_FAILURE(status)) {
1429                 goto error;
1430         }
1431
1432         return 0;
1433       error:
1434         printk(KERN_ERR PREFIX "Could not use ECDT\n");
1435         kfree(ec_ecdt);
1436         ec_ecdt = NULL;
1437
1438         return -ENODEV;
1439 }
1440
1441 static int __init acpi_ec_intr_get_real_ecdt(void)
1442 {
1443         acpi_status status;
1444         struct acpi_table_ecdt *ecdt_ptr;
1445
1446         status = acpi_get_firmware_table("ECDT", 1, ACPI_LOGICAL_ADDRESSING,
1447                                          (struct acpi_table_header **)
1448                                          &ecdt_ptr);
1449         if (ACPI_FAILURE(status))
1450                 return -ENODEV;
1451
1452         printk(KERN_INFO PREFIX "Found ECDT\n");
1453
1454         /*
1455          * Generate a temporary ec context to use until the namespace is scanned
1456          */
1457         ec_ecdt = kmalloc(sizeof(union acpi_ec), GFP_KERNEL);
1458         if (!ec_ecdt)
1459                 return -ENOMEM;
1460         memset(ec_ecdt, 0, sizeof(union acpi_ec));
1461
1462         init_MUTEX(&ec_ecdt->intr.sem);
1463         init_waitqueue_head(&ec_ecdt->intr.wait);
1464         ec_ecdt->common.command_addr = ecdt_ptr->ec_control;
1465         ec_ecdt->common.status_addr = ecdt_ptr->ec_control;
1466         ec_ecdt->common.data_addr = ecdt_ptr->ec_data;
1467         ec_ecdt->common.gpe_bit = ecdt_ptr->gpe_bit;
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 __initdata acpi_fake_ecdt_enabled;
1488 int __init acpi_ec_ecdt_probe(void)
1489 {
1490         acpi_status status;
1491         int ret;
1492
1493         ret = acpi_ec_get_real_ecdt();
1494         /* Try to make a fake ECDT */
1495         if (ret && acpi_fake_ecdt_enabled) {
1496                 ret = acpi_ec_fake_ecdt();
1497         }
1498
1499         if (ret)
1500                 return 0;
1501
1502         /*
1503          * Install GPE handler
1504          */
1505         status = acpi_install_gpe_handler(NULL, ec_ecdt->common.gpe_bit,
1506                                           ACPI_GPE_EDGE_TRIGGERED,
1507                                           &acpi_ec_gpe_handler, ec_ecdt);
1508         if (ACPI_FAILURE(status)) {
1509                 goto error;
1510         }
1511         acpi_set_gpe_type(NULL, ec_ecdt->common.gpe_bit, ACPI_GPE_TYPE_RUNTIME);
1512         acpi_enable_gpe(NULL, ec_ecdt->common.gpe_bit, ACPI_NOT_ISR);
1513
1514         status = acpi_install_address_space_handler(ACPI_ROOT_OBJECT,
1515                                                     ACPI_ADR_SPACE_EC,
1516                                                     &acpi_ec_space_handler,
1517                                                     &acpi_ec_space_setup,
1518                                                     ec_ecdt);
1519         if (ACPI_FAILURE(status)) {
1520                 acpi_remove_gpe_handler(NULL, ec_ecdt->common.gpe_bit,
1521                                         &acpi_ec_gpe_handler);
1522                 goto error;
1523         }
1524
1525         return 0;
1526
1527       error:
1528         printk(KERN_ERR PREFIX "Could not use ECDT\n");
1529         kfree(ec_ecdt);
1530         ec_ecdt = NULL;
1531
1532         return -ENODEV;
1533 }
1534
1535 static int __init acpi_ec_init(void)
1536 {
1537         int result = 0;
1538
1539         ACPI_FUNCTION_TRACE("acpi_ec_init");
1540
1541         if (acpi_disabled)
1542                 return_VALUE(0);
1543
1544         acpi_ec_dir = proc_mkdir(ACPI_EC_CLASS, acpi_root_dir);
1545         if (!acpi_ec_dir)
1546                 return_VALUE(-ENODEV);
1547
1548         /* Now register the driver for the EC */
1549         result = acpi_bus_register_driver(&acpi_ec_driver);
1550         if (result < 0) {
1551                 remove_proc_entry(ACPI_EC_CLASS, acpi_root_dir);
1552                 return_VALUE(-ENODEV);
1553         }
1554
1555         return_VALUE(result);
1556 }
1557
1558 subsys_initcall(acpi_ec_init);
1559
1560 /* EC driver currently not unloadable */
1561 #if 0
1562 static void __exit acpi_ec_exit(void)
1563 {
1564         ACPI_FUNCTION_TRACE("acpi_ec_exit");
1565
1566         acpi_bus_unregister_driver(&acpi_ec_driver);
1567
1568         remove_proc_entry(ACPI_EC_CLASS, acpi_root_dir);
1569
1570         return_VOID;
1571 }
1572 #endif                          /* 0 */
1573
1574 static int __init acpi_fake_ecdt_setup(char *str)
1575 {
1576         acpi_fake_ecdt_enabled = 1;
1577         return 1;
1578 }
1579
1580 __setup("acpi_fake_ecdt", acpi_fake_ecdt_setup);
1581 static int __init acpi_ec_set_intr_mode(char *str)
1582 {
1583         int intr;
1584
1585         if (!get_option(&str, &intr))
1586                 return 0;
1587
1588         if (intr) {
1589                 acpi_ec_poll_mode = EC_INTR;
1590                 acpi_ec_driver.ops.add = acpi_ec_intr_add;
1591         } else {
1592                 acpi_ec_poll_mode = EC_POLL;
1593                 acpi_ec_driver.ops.add = acpi_ec_poll_add;
1594         }
1595         printk(KERN_INFO PREFIX "EC %s mode.\n", intr ? "interrupt" : "polling");
1596         return 1;
1597 }
1598
1599 __setup("ec_intr=", acpi_ec_set_intr_mode);