SAFE public projects git trees. - safe/jmp/linux-2.6/blob - drivers/acpi/ec.c

   1 /*
   2  *  ec.c - ACPI Embedded Controller Driver (v2.1)
   3  *
   4  *  Copyright (C) 2006-2008 Alexey Starikovskiy <astarikovskiy@suse.de>
   5  *  Copyright (C) 2006 Denis Sadykov <denis.m.sadykov@intel.com>
   6  *  Copyright (C) 2004 Luming Yu <luming.yu@intel.com>
   7  *  Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
   8  *  Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
   9  *
  10  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  11  *
  12  *  This program is free software; you can redistribute it and/or modify
  13  *  it under the terms of the GNU General Public License as published by
  14  *  the Free Software Foundation; either version 2 of the License, or (at
  15  *  your option) any later version.
  16  *
  17  *  This program is distributed in the hope that it will be useful, but
  18  *  WITHOUT ANY WARRANTY; without even the implied warranty of
  19  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  20  *  General Public License for more details.
  21  *
  22  *  You should have received a copy of the GNU General Public License along
  23  *  with this program; if not, write to the Free Software Foundation, Inc.,
  24  *  59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
  25  *
  26  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  27  */
  28
  29 /* Uncomment next line to get verbose printout */
  30 /* #define DEBUG */
  31
  32 #include <linux/kernel.h>
  33 #include <linux/module.h>
  34 #include <linux/init.h>
  35 #include <linux/types.h>
  36 #include <linux/delay.h>
  37 #include <linux/proc_fs.h>
  38 #include <linux/seq_file.h>
  39 #include <linux/interrupt.h>
  40 #include <linux/list.h>
  41 #include <linux/spinlock.h>
  42 #include <asm/io.h>
  43 #include <acpi/acpi_bus.h>
  44 #include <acpi/acpi_drivers.h>
  45 #include <linux/dmi.h>
  46
  47 #define ACPI_EC_CLASS                   "embedded_controller"
  48 #define ACPI_EC_DEVICE_NAME             "Embedded Controller"
  49 #define ACPI_EC_FILE_INFO               "info"
  50
  51 #define PREFIX                          "ACPI: EC: "
  52
  53 /* EC status register */
  54 #define ACPI_EC_FLAG_OBF        0x01    /* Output buffer full */
  55 #define ACPI_EC_FLAG_IBF        0x02    /* Input buffer full */
  56 #define ACPI_EC_FLAG_BURST      0x10    /* burst mode */
  57 #define ACPI_EC_FLAG_SCI        0x20    /* EC-SCI occurred */
  58
  59 /* EC commands */
  60 enum ec_command {
  61         ACPI_EC_COMMAND_READ = 0x80,
  62         ACPI_EC_COMMAND_WRITE = 0x81,
  63         ACPI_EC_BURST_ENABLE = 0x82,
  64         ACPI_EC_BURST_DISABLE = 0x83,
  65         ACPI_EC_COMMAND_QUERY = 0x84,
  66 };
  67
  68 #define ACPI_EC_DELAY           500     /* Wait 500ms max. during EC ops */
  69 #define ACPI_EC_UDELAY_GLK      1000    /* Wait 1ms max. to get global lock */
  70 #define ACPI_EC_CDELAY          10      /* Wait 10us before polling EC */
  71 #define ACPI_EC_MSI_UDELAY      550     /* Wait 550us for MSI EC */
  72
  73 #define ACPI_EC_STORM_THRESHOLD 8       /* number of false interrupts
  74                                            per one transaction */
  75
  76 enum {
  77         EC_FLAGS_QUERY_PENDING,         /* Query is pending */
  78         EC_FLAGS_GPE_STORM,             /* GPE storm detected */
  79         EC_FLAGS_HANDLERS_INSTALLED,    /* Handlers for GPE and
  80                                          * OpReg are installed */
  81         EC_FLAGS_FROZEN,                /* Transactions are suspended */
  82 };
  83
  84 /* If we find an EC via the ECDT, we need to keep a ptr to its context */
  85 /* External interfaces use first EC only, so remember */
  86 typedef int (*acpi_ec_query_func) (void *data);
  87
  88 struct acpi_ec_query_handler {
  89         struct list_head node;
  90         acpi_ec_query_func func;
  91         acpi_handle handle;
  92         void *data;
  93         u8 query_bit;
  94 };
  95
  96 struct transaction {
  97         const u8 *wdata;
  98         u8 *rdata;
  99         unsigned short irq_count;
 100         u8 command;
 101         u8 wi;
 102         u8 ri;
 103         u8 wlen;
 104         u8 rlen;
 105         bool done;
 106 };
 107
 108 static struct acpi_ec {
 109         acpi_handle handle;
 110         unsigned long gpe;
 111         unsigned long command_addr;
 112         unsigned long data_addr;
 113         unsigned long global_lock;
 114         unsigned long flags;
 115         struct mutex lock;
 116         wait_queue_head_t wait;
 117         struct list_head list;
 118         struct transaction *curr;
 119         spinlock_t curr_lock;
 120 } *boot_ec, *first_ec;
 121
 122 static int EC_FLAGS_MSI; /* Out-of-spec MSI controller */
 123 static int EC_FLAGS_VALIDATE_ECDT; /* ASUStec ECDTs need to be validated */
 124 static int EC_FLAGS_SKIP_DSDT_SCAN; /* Not all BIOS survive early DSDT scan */
 125
 126 /* --------------------------------------------------------------------------
 127                              Transaction Management
 128    -------------------------------------------------------------------------- */
 129
 130 static inline u8 acpi_ec_read_status(struct acpi_ec *ec)
 131 {
 132         u8 x = inb(ec->command_addr);
 133         pr_debug(PREFIX "---> status = 0x%2.2x\n", x);
 134         return x;
 135 }
 136
 137 static inline u8 acpi_ec_read_data(struct acpi_ec *ec)
 138 {
 139         u8 x = inb(ec->data_addr);
 140         pr_debug(PREFIX "---> data = 0x%2.2x\n", x);
 141         return x;
 142 }
 143
 144 static inline void acpi_ec_write_cmd(struct acpi_ec *ec, u8 command)
 145 {
 146         pr_debug(PREFIX "<--- command = 0x%2.2x\n", command);
 147         outb(command, ec->command_addr);
 148 }
 149
 150 static inline void acpi_ec_write_data(struct acpi_ec *ec, u8 data)
 151 {
 152         pr_debug(PREFIX "<--- data = 0x%2.2x\n", data);
 153         outb(data, ec->data_addr);
 154 }
 155
 156 static int ec_transaction_done(struct acpi_ec *ec)
 157 {
 158         unsigned long flags;
 159         int ret = 0;
 160         spin_lock_irqsave(&ec->curr_lock, flags);
 161         if (!ec->curr || ec->curr->done)
 162                 ret = 1;
 163         spin_unlock_irqrestore(&ec->curr_lock, flags);
 164         return ret;
 165 }
 166
 167 static void start_transaction(struct acpi_ec *ec)
 168 {
 169         ec->curr->irq_count = ec->curr->wi = ec->curr->ri = 0;
 170         ec->curr->done = false;
 171         acpi_ec_write_cmd(ec, ec->curr->command);
 172 }
 173
 174 static void advance_transaction(struct acpi_ec *ec, u8 status)
 175 {
 176         unsigned long flags;
 177         spin_lock_irqsave(&ec->curr_lock, flags);
 178         if (!ec->curr)
 179                 goto unlock;
 180         if (ec->curr->wlen > ec->curr->wi) {
 181                 if ((status & ACPI_EC_FLAG_IBF) == 0)
 182                         acpi_ec_write_data(ec,
 183                                 ec->curr->wdata[ec->curr->wi++]);
 184                 else
 185                         goto err;
 186         } else if (ec->curr->rlen > ec->curr->ri) {
 187                 if ((status & ACPI_EC_FLAG_OBF) == 1) {
 188                         ec->curr->rdata[ec->curr->ri++] = acpi_ec_read_data(ec);
 189                         if (ec->curr->rlen == ec->curr->ri)
 190                                 ec->curr->done = true;
 191                 } else
 192                         goto err;
 193         } else if (ec->curr->wlen == ec->curr->wi &&
 194                    (status & ACPI_EC_FLAG_IBF) == 0)
 195                 ec->curr->done = true;
 196         goto unlock;
 197 err:
 198         /* false interrupt, state didn't change */
 199         if (in_interrupt())
 200                 ++ec->curr->irq_count;
 201 unlock:
 202         spin_unlock_irqrestore(&ec->curr_lock, flags);
 203 }
 204
 205 static int acpi_ec_sync_query(struct acpi_ec *ec);
 206
 207 static int ec_check_sci_sync(struct acpi_ec *ec, u8 state)
 208 {
 209         if (state & ACPI_EC_FLAG_SCI) {
 210                 if (!test_and_set_bit(EC_FLAGS_QUERY_PENDING, &ec->flags))
 211                         return acpi_ec_sync_query(ec);
 212         }
 213         return 0;
 214 }
 215
 216 static int ec_poll(struct acpi_ec *ec)
 217 {
 218         unsigned long flags;
 219         int repeat = 2; /* number of command restarts */
 220         while (repeat--) {
 221                 unsigned long delay = jiffies +
 222                         msecs_to_jiffies(ACPI_EC_DELAY);
 223                 do {
 224                         /* don't sleep with disabled interrupts */
 225                         if (EC_FLAGS_MSI || irqs_disabled()) {
 226                                 udelay(ACPI_EC_MSI_UDELAY);
 227                                 if (ec_transaction_done(ec))
 228                                         return 0;
 229                         } else {
 230                                 if (wait_event_timeout(ec->wait,
 231                                                 ec_transaction_done(ec),
 232                                                 msecs_to_jiffies(1)))
 233                                         return 0;
 234                         }
 235                         advance_transaction(ec, acpi_ec_read_status(ec));
 236                 } while (time_before(jiffies, delay));
 237                 if (acpi_ec_read_status(ec) & ACPI_EC_FLAG_IBF)
 238                         break;
 239                 pr_debug(PREFIX "controller reset, restart transaction\n");
 240                 spin_lock_irqsave(&ec->curr_lock, flags);
 241                 start_transaction(ec);
 242                 spin_unlock_irqrestore(&ec->curr_lock, flags);
 243         }
 244         return -ETIME;
 245 }
 246
 247 static int acpi_ec_transaction_unlocked(struct acpi_ec *ec,
 248                                         struct transaction *t)
 249 {
 250         unsigned long tmp;
 251         int ret = 0;
 252         if (EC_FLAGS_MSI)
 253                 udelay(ACPI_EC_MSI_UDELAY);
 254         /* start transaction */
 255         spin_lock_irqsave(&ec->curr_lock, tmp);
 256         /* following two actions should be kept atomic */
 257         ec->curr = t;
 258         start_transaction(ec);
 259         if (ec->curr->command == ACPI_EC_COMMAND_QUERY)
 260                 clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags);
 261         spin_unlock_irqrestore(&ec->curr_lock, tmp);
 262         ret = ec_poll(ec);
 263         spin_lock_irqsave(&ec->curr_lock, tmp);
 264         ec->curr = NULL;
 265         spin_unlock_irqrestore(&ec->curr_lock, tmp);
 266         return ret;
 267 }
 268
 269 static int ec_check_ibf0(struct acpi_ec *ec)
 270 {
 271         u8 status = acpi_ec_read_status(ec);
 272         return (status & ACPI_EC_FLAG_IBF) == 0;
 273 }
 274
 275 static int ec_wait_ibf0(struct acpi_ec *ec)
 276 {
 277         unsigned long delay = jiffies + msecs_to_jiffies(ACPI_EC_DELAY);
 278         /* interrupt wait manually if GPE mode is not active */
 279         while (time_before(jiffies, delay))
 280                 if (wait_event_timeout(ec->wait, ec_check_ibf0(ec),
 281                                         msecs_to_jiffies(1)))
 282                         return 0;
 283         return -ETIME;
 284 }
 285
 286 static int acpi_ec_transaction(struct acpi_ec *ec, struct transaction *t)
 287 {
 288         int status;
 289         u32 glk;
 290         if (!ec || (!t) || (t->wlen && !t->wdata) || (t->rlen && !t->rdata))
 291                 return -EINVAL;
 292         if (t->rdata)
 293                 memset(t->rdata, 0, t->rlen);
 294         mutex_lock(&ec->lock);
 295         if (test_bit(EC_FLAGS_FROZEN, &ec->flags)) {
 296                 status = -EINVAL;
 297                 goto unlock;
 298         }
 299         if (ec->global_lock) {
 300                 status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk);
 301                 if (ACPI_FAILURE(status)) {
 302                         status = -ENODEV;
 303                         goto unlock;
 304                 }
 305         }
 306         if (ec_wait_ibf0(ec)) {
 307                 pr_err(PREFIX "input buffer is not empty, "
 308                                 "aborting transaction\n");
 309                 status = -ETIME;
 310                 goto end;
 311         }
 312         pr_debug(PREFIX "transaction start\n");
 313         /* disable GPE during transaction if storm is detected */
 314         if (test_bit(EC_FLAGS_GPE_STORM, &ec->flags)) {
 315                 /*
 316                  * It has to be disabled at the hardware level regardless of the
 317                  * GPE reference counting, so that it doesn't trigger.
 318                  */
 319                 acpi_set_gpe(NULL, ec->gpe, ACPI_GPE_DISABLE);
 320         }
 321
 322         status = acpi_ec_transaction_unlocked(ec, t);
 323
 324         /* check if we received SCI during transaction */
 325         ec_check_sci_sync(ec, acpi_ec_read_status(ec));
 326         if (test_bit(EC_FLAGS_GPE_STORM, &ec->flags)) {
 327                 msleep(1);
 328                 /*
 329                  * It is safe to enable the GPE outside of the transaction.  Use
 330                  * acpi_set_gpe() for that, since we used it to disable the GPE
 331                  * above.
 332                  */
 333                 acpi_set_gpe(NULL, ec->gpe, ACPI_GPE_ENABLE);
 334         } else if (t->irq_count > ACPI_EC_STORM_THRESHOLD) {
 335                 pr_info(PREFIX "GPE storm detected, "
 336                         "transactions will use polling mode\n");
 337                 set_bit(EC_FLAGS_GPE_STORM, &ec->flags);
 338         }
 339         pr_debug(PREFIX "transaction end\n");
 340 end:
 341         if (ec->global_lock)
 342                 acpi_release_global_lock(glk);
 343 unlock:
 344         mutex_unlock(&ec->lock);
 345         return status;
 346 }
 347
 348 static int acpi_ec_burst_enable(struct acpi_ec *ec)
 349 {
 350         u8 d;
 351         struct transaction t = {.command = ACPI_EC_BURST_ENABLE,
 352                                 .wdata = NULL, .rdata = &d,
 353                                 .wlen = 0, .rlen = 1};
 354
 355         return acpi_ec_transaction(ec, &t);
 356 }
 357
 358 static int acpi_ec_burst_disable(struct acpi_ec *ec)
 359 {
 360         struct transaction t = {.command = ACPI_EC_BURST_DISABLE,
 361                                 .wdata = NULL, .rdata = NULL,
 362                                 .wlen = 0, .rlen = 0};
 363
 364         return (acpi_ec_read_status(ec) & ACPI_EC_FLAG_BURST) ?
 365                                 acpi_ec_transaction(ec, &t) : 0;
 366 }
 367
 368 static int acpi_ec_read(struct acpi_ec *ec, u8 address, u8 * data)
 369 {
 370         int result;
 371         u8 d;
 372         struct transaction t = {.command = ACPI_EC_COMMAND_READ,
 373                                 .wdata = &address, .rdata = &d,
 374                                 .wlen = 1, .rlen = 1};
 375
 376         result = acpi_ec_transaction(ec, &t);
 377         *data = d;
 378         return result;
 379 }
 380
 381 static int acpi_ec_write(struct acpi_ec *ec, u8 address, u8 data)
 382 {
 383         u8 wdata[2] = { address, data };
 384         struct transaction t = {.command = ACPI_EC_COMMAND_WRITE,
 385                                 .wdata = wdata, .rdata = NULL,
 386                                 .wlen = 2, .rlen = 0};
 387
 388         return acpi_ec_transaction(ec, &t);
 389 }
 390
 391 /*
 392  * Externally callable EC access functions. For now, assume 1 EC only
 393  */
 394 int ec_burst_enable(void)
 395 {
 396         if (!first_ec)
 397                 return -ENODEV;
 398         return acpi_ec_burst_enable(first_ec);
 399 }
 400
 401 EXPORT_SYMBOL(ec_burst_enable);
 402
 403 int ec_burst_disable(void)
 404 {
 405         if (!first_ec)
 406                 return -ENODEV;
 407         return acpi_ec_burst_disable(first_ec);
 408 }
 409
 410 EXPORT_SYMBOL(ec_burst_disable);
 411
 412 int ec_read(u8 addr, u8 * val)
 413 {
 414         int err;
 415         u8 temp_data;
 416
 417         if (!first_ec)
 418                 return -ENODEV;
 419
 420         err = acpi_ec_read(first_ec, addr, &temp_data);
 421
 422         if (!err) {
 423                 *val = temp_data;
 424                 return 0;
 425         } else
 426                 return err;
 427 }
 428
 429 EXPORT_SYMBOL(ec_read);
 430
 431 int ec_write(u8 addr, u8 val)
 432 {
 433         int err;
 434
 435         if (!first_ec)
 436                 return -ENODEV;
 437
 438         err = acpi_ec_write(first_ec, addr, val);
 439
 440         return err;
 441 }
 442
 443 EXPORT_SYMBOL(ec_write);
 444
 445 int ec_transaction(u8 command,
 446                    const u8 * wdata, unsigned wdata_len,
 447                    u8 * rdata, unsigned rdata_len,
 448                    int force_poll)
 449 {
 450         struct transaction t = {.command = command,
 451                                 .wdata = wdata, .rdata = rdata,
 452                                 .wlen = wdata_len, .rlen = rdata_len};
 453         if (!first_ec)
 454                 return -ENODEV;
 455
 456         return acpi_ec_transaction(first_ec, &t);
 457 }
 458
 459 EXPORT_SYMBOL(ec_transaction);
 460
 461 void acpi_ec_suspend_transactions(void)
 462 {
 463         struct acpi_ec *ec = first_ec;
 464
 465         if (!ec)
 466                 return;
 467
 468         mutex_lock(&ec->lock);
 469         /* Prevent transactions from being carried out */
 470         set_bit(EC_FLAGS_FROZEN, &ec->flags);
 471         mutex_unlock(&ec->lock);
 472 }
 473
 474 void acpi_ec_resume_transactions(void)
 475 {
 476         struct acpi_ec *ec = first_ec;
 477
 478         if (!ec)
 479                 return;
 480
 481         mutex_lock(&ec->lock);
 482         /* Allow transactions to be carried out again */
 483         clear_bit(EC_FLAGS_FROZEN, &ec->flags);
 484         mutex_unlock(&ec->lock);
 485 }
 486
 487 static int acpi_ec_query_unlocked(struct acpi_ec *ec, u8 * data)
 488 {
 489         int result;
 490         u8 d;
 491         struct transaction t = {.command = ACPI_EC_COMMAND_QUERY,
 492                                 .wdata = NULL, .rdata = &d,
 493                                 .wlen = 0, .rlen = 1};
 494         if (!ec || !data)
 495                 return -EINVAL;
 496         /*
 497          * Query the EC to find out which _Qxx method we need to evaluate.
 498          * Note that successful completion of the query causes the ACPI_EC_SCI
 499          * bit to be cleared (and thus clearing the interrupt source).
 500          */
 501         result = acpi_ec_transaction_unlocked(ec, &t);
 502         if (result)
 503                 return result;
 504         if (!d)
 505                 return -ENODATA;
 506         *data = d;
 507         return 0;
 508 }
 509
 510 /* --------------------------------------------------------------------------
 511                                 Event Management
 512    -------------------------------------------------------------------------- */
 513 int acpi_ec_add_query_handler(struct acpi_ec *ec, u8 query_bit,
 514                               acpi_handle handle, acpi_ec_query_func func,
 515                               void *data)
 516 {
 517         struct acpi_ec_query_handler *handler =
 518             kzalloc(sizeof(struct acpi_ec_query_handler), GFP_KERNEL);
 519         if (!handler)
 520                 return -ENOMEM;
 521
 522         handler->query_bit = query_bit;
 523         handler->handle = handle;
 524         handler->func = func;
 525         handler->data = data;
 526         mutex_lock(&ec->lock);
 527         list_add(&handler->node, &ec->list);
 528         mutex_unlock(&ec->lock);
 529         return 0;
 530 }
 531
 532 EXPORT_SYMBOL_GPL(acpi_ec_add_query_handler);
 533
 534 void acpi_ec_remove_query_handler(struct acpi_ec *ec, u8 query_bit)
 535 {
 536         struct acpi_ec_query_handler *handler, *tmp;
 537         mutex_lock(&ec->lock);
 538         list_for_each_entry_safe(handler, tmp, &ec->list, node) {
 539                 if (query_bit == handler->query_bit) {
 540                         list_del(&handler->node);
 541                         kfree(handler);
 542                 }
 543         }
 544         mutex_unlock(&ec->lock);
 545 }
 546
 547 EXPORT_SYMBOL_GPL(acpi_ec_remove_query_handler);
 548
 549 static void acpi_ec_run(void *cxt)
 550 {
 551         struct acpi_ec_query_handler *handler = cxt;
 552         if (!handler)
 553                 return;
 554         pr_debug(PREFIX "start query execution\n");
 555         if (handler->func)
 556                 handler->func(handler->data);
 557         else if (handler->handle)
 558                 acpi_evaluate_object(handler->handle, NULL, NULL, NULL);
 559         pr_debug(PREFIX "stop query execution\n");
 560         kfree(handler);
 561 }
 562
 563 static int acpi_ec_sync_query(struct acpi_ec *ec)
 564 {
 565         u8 value = 0;
 566         int status;
 567         struct acpi_ec_query_handler *handler, *copy;
 568         if ((status = acpi_ec_query_unlocked(ec, &value)))
 569                 return status;
 570         list_for_each_entry(handler, &ec->list, node) {
 571                 if (value == handler->query_bit) {
 572                         /* have custom handler for this bit */
 573                         copy = kmalloc(sizeof(*handler), GFP_KERNEL);
 574                         if (!copy)
 575                                 return -ENOMEM;
 576                         memcpy(copy, handler, sizeof(*copy));
 577                         pr_debug(PREFIX "push query execution (0x%2x) on queue\n", value);
 578                         return acpi_os_execute((copy->func) ?
 579                                 OSL_NOTIFY_HANDLER : OSL_GPE_HANDLER,
 580                                 acpi_ec_run, copy);
 581                 }
 582         }
 583         return 0;
 584 }
 585
 586 static void acpi_ec_gpe_query(void *ec_cxt)
 587 {
 588         struct acpi_ec *ec = ec_cxt;
 589         if (!ec)
 590                 return;
 591         mutex_lock(&ec->lock);
 592         acpi_ec_sync_query(ec);
 593         mutex_unlock(&ec->lock);
 594 }
 595
 596 static void acpi_ec_gpe_query(void *ec_cxt);
 597
 598 static int ec_check_sci(struct acpi_ec *ec, u8 state)
 599 {
 600         if (state & ACPI_EC_FLAG_SCI) {
 601                 if (!test_and_set_bit(EC_FLAGS_QUERY_PENDING, &ec->flags)) {
 602                         pr_debug(PREFIX "push gpe query to the queue\n");
 603                         return acpi_os_execute(OSL_NOTIFY_HANDLER,
 604                                 acpi_ec_gpe_query, ec);
 605                 }
 606         }
 607         return 0;
 608 }
 609
 610 static u32 acpi_ec_gpe_handler(void *data)
 611 {
 612         struct acpi_ec *ec = data;
 613
 614         pr_debug(PREFIX "~~~> interrupt\n");
 615
 616         advance_transaction(ec, acpi_ec_read_status(ec));
 617         if (ec_transaction_done(ec) &&
 618             (acpi_ec_read_status(ec) & ACPI_EC_FLAG_IBF) == 0) {
 619                 wake_up(&ec->wait);
 620                 ec_check_sci(ec, acpi_ec_read_status(ec));
 621         }
 622         return ACPI_INTERRUPT_HANDLED;
 623 }
 624
 625 /* --------------------------------------------------------------------------
 626                              Address Space Management
 627    -------------------------------------------------------------------------- */
 628
 629 static acpi_status
 630 acpi_ec_space_handler(u32 function, acpi_physical_address address,
 631                       u32 bits, u64 *value,
 632                       void *handler_context, void *region_context)
 633 {
 634         struct acpi_ec *ec = handler_context;
 635         int result = 0, i;
 636         u8 temp = 0;
 637
 638         if ((address > 0xFF) || !value || !handler_context)
 639                 return AE_BAD_PARAMETER;
 640
 641         if (function != ACPI_READ && function != ACPI_WRITE)
 642                 return AE_BAD_PARAMETER;
 643
 644         if (bits != 8 && acpi_strict)
 645                 return AE_BAD_PARAMETER;
 646
 647         if (EC_FLAGS_MSI)
 648                 acpi_ec_burst_enable(ec);
 649
 650         if (function == ACPI_READ) {
 651                 result = acpi_ec_read(ec, address, &temp);
 652                 *value = temp;
 653         } else {
 654                 temp = 0xff & (*value);
 655                 result = acpi_ec_write(ec, address, temp);
 656         }
 657
 658         for (i = 8; unlikely(bits - i > 0); i += 8) {
 659                 ++address;
 660                 if (function == ACPI_READ) {
 661                         result = acpi_ec_read(ec, address, &temp);
 662                         (*value) |= ((u64)temp) << i;
 663                 } else {
 664                         temp = 0xff & ((*value) >> i);
 665                         result = acpi_ec_write(ec, address, temp);
 666                 }
 667         }
 668
 669         if (EC_FLAGS_MSI)
 670                 acpi_ec_burst_disable(ec);
 671
 672         switch (result) {
 673         case -EINVAL:
 674                 return AE_BAD_PARAMETER;
 675                 break;
 676         case -ENODEV:
 677                 return AE_NOT_FOUND;
 678                 break;
 679         case -ETIME:
 680                 return AE_TIME;
 681                 break;
 682         default:
 683                 return AE_OK;
 684         }
 685 }
 686
 687 /* --------------------------------------------------------------------------
 688                               FS Interface (/proc)
 689    -------------------------------------------------------------------------- */
 690
 691 static struct proc_dir_entry *acpi_ec_dir;
 692
 693 static int acpi_ec_read_info(struct seq_file *seq, void *offset)
 694 {
 695         struct acpi_ec *ec = seq->private;
 696
 697         if (!ec)
 698                 goto end;
 699
 700         seq_printf(seq, "gpe:\t\t\t0x%02x\n", (u32) ec->gpe);
 701         seq_printf(seq, "ports:\t\t\t0x%02x, 0x%02x\n",
 702                    (unsigned)ec->command_addr, (unsigned)ec->data_addr);
 703         seq_printf(seq, "use global lock:\t%s\n",
 704                    ec->global_lock ? "yes" : "no");
 705       end:
 706         return 0;
 707 }
 708
 709 static int acpi_ec_info_open_fs(struct inode *inode, struct file *file)
 710 {
 711         return single_open(file, acpi_ec_read_info, PDE(inode)->data);
 712 }
 713
 714 static const struct file_operations acpi_ec_info_ops = {
 715         .open = acpi_ec_info_open_fs,
 716         .read = seq_read,
 717         .llseek = seq_lseek,
 718         .release = single_release,
 719         .owner = THIS_MODULE,
 720 };
 721
 722 static int acpi_ec_add_fs(struct acpi_device *device)
 723 {
 724         struct proc_dir_entry *entry = NULL;
 725
 726         if (!acpi_device_dir(device)) {
 727                 acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device),
 728                                                      acpi_ec_dir);
 729                 if (!acpi_device_dir(device))
 730                         return -ENODEV;
 731         }
 732
 733         entry = proc_create_data(ACPI_EC_FILE_INFO, S_IRUGO,
 734                                  acpi_device_dir(device),
 735                                  &acpi_ec_info_ops, acpi_driver_data(device));
 736         if (!entry)
 737                 return -ENODEV;
 738         return 0;
 739 }
 740
 741 static int acpi_ec_remove_fs(struct acpi_device *device)
 742 {
 743
 744         if (acpi_device_dir(device)) {
 745                 remove_proc_entry(ACPI_EC_FILE_INFO, acpi_device_dir(device));
 746                 remove_proc_entry(acpi_device_bid(device), acpi_ec_dir);
 747                 acpi_device_dir(device) = NULL;
 748         }
 749
 750         return 0;
 751 }
 752
 753 /* --------------------------------------------------------------------------
 754                                Driver Interface
 755    -------------------------------------------------------------------------- */
 756 static acpi_status
 757 ec_parse_io_ports(struct acpi_resource *resource, void *context);
 758
 759 static struct acpi_ec *make_acpi_ec(void)
 760 {
 761         struct acpi_ec *ec = kzalloc(sizeof(struct acpi_ec), GFP_KERNEL);
 762         if (!ec)
 763                 return NULL;
 764         ec->flags = 1 << EC_FLAGS_QUERY_PENDING;
 765         mutex_init(&ec->lock);
 766         init_waitqueue_head(&ec->wait);
 767         INIT_LIST_HEAD(&ec->list);
 768         spin_lock_init(&ec->curr_lock);
 769         return ec;
 770 }
 771
 772 static acpi_status
 773 acpi_ec_register_query_methods(acpi_handle handle, u32 level,
 774                                void *context, void **return_value)
 775 {
 776         char node_name[5];
 777         struct acpi_buffer buffer = { sizeof(node_name), node_name };
 778         struct acpi_ec *ec = context;
 779         int value = 0;
 780         acpi_status status;
 781
 782         status = acpi_get_name(handle, ACPI_SINGLE_NAME, &buffer);
 783
 784         if (ACPI_SUCCESS(status) && sscanf(node_name, "_Q%x", &value) == 1) {
 785                 acpi_ec_add_query_handler(ec, value, handle, NULL, NULL);
 786         }
 787         return AE_OK;
 788 }
 789
 790 static acpi_status
 791 ec_parse_device(acpi_handle handle, u32 Level, void *context, void **retval)
 792 {
 793         acpi_status status;
 794         unsigned long long tmp = 0;
 795
 796         struct acpi_ec *ec = context;
 797
 798         /* clear addr values, ec_parse_io_ports depend on it */
 799         ec->command_addr = ec->data_addr = 0;
 800
 801         status = acpi_walk_resources(handle, METHOD_NAME__CRS,
 802                                      ec_parse_io_ports, ec);
 803         if (ACPI_FAILURE(status))
 804                 return status;
 805
 806         /* Get GPE bit assignment (EC events). */
 807         /* TODO: Add support for _GPE returning a package */
 808         status = acpi_evaluate_integer(handle, "_GPE", NULL, &tmp);
 809         if (ACPI_FAILURE(status))
 810                 return status;
 811         ec->gpe = tmp;
 812         /* Use the global lock for all EC transactions? */
 813         tmp = 0;
 814         acpi_evaluate_integer(handle, "_GLK", NULL, &tmp);
 815         ec->global_lock = tmp;
 816         ec->handle = handle;
 817         return AE_CTRL_TERMINATE;
 818 }
 819
 820 static int ec_install_handlers(struct acpi_ec *ec)
 821 {
 822         acpi_status status;
 823         if (test_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags))
 824                 return 0;
 825         status = acpi_install_gpe_handler(NULL, ec->gpe,
 826                                   ACPI_GPE_EDGE_TRIGGERED,
 827                                   &acpi_ec_gpe_handler, ec);
 828         if (ACPI_FAILURE(status))
 829                 return -ENODEV;
 830
 831         acpi_enable_gpe(NULL, ec->gpe, ACPI_GPE_TYPE_RUNTIME);
 832         status = acpi_install_address_space_handler(ec->handle,
 833                                                     ACPI_ADR_SPACE_EC,
 834                                                     &acpi_ec_space_handler,
 835                                                     NULL, ec);
 836         if (ACPI_FAILURE(status)) {
 837                 if (status == AE_NOT_FOUND) {
 838                         /*
 839                          * Maybe OS fails in evaluating the _REG object.
 840                          * The AE_NOT_FOUND error will be ignored and OS
 841                          * continue to initialize EC.
 842                          */
 843                         printk(KERN_ERR "Fail in evaluating the _REG object"
 844                                 " of EC device. Broken bios is suspected.\n");
 845                 } else {
 846                         acpi_remove_gpe_handler(NULL, ec->gpe,
 847                                 &acpi_ec_gpe_handler);
 848                         acpi_disable_gpe(NULL, ec->gpe, ACPI_GPE_TYPE_RUNTIME);
 849                         return -ENODEV;
 850                 }
 851         }
 852
 853         set_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags);
 854         return 0;
 855 }
 856
 857 static void ec_remove_handlers(struct acpi_ec *ec)
 858 {
 859         acpi_disable_gpe(NULL, ec->gpe, ACPI_GPE_TYPE_RUNTIME);
 860         if (ACPI_FAILURE(acpi_remove_address_space_handler(ec->handle,
 861                                 ACPI_ADR_SPACE_EC, &acpi_ec_space_handler)))
 862                 pr_err(PREFIX "failed to remove space handler\n");
 863         if (ACPI_FAILURE(acpi_remove_gpe_handler(NULL, ec->gpe,
 864                                 &acpi_ec_gpe_handler)))
 865                 pr_err(PREFIX "failed to remove gpe handler\n");
 866         clear_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags);
 867 }
 868
 869 static int acpi_ec_add(struct acpi_device *device)
 870 {
 871         struct acpi_ec *ec = NULL;
 872         int ret;
 873
 874         strcpy(acpi_device_name(device), ACPI_EC_DEVICE_NAME);
 875         strcpy(acpi_device_class(device), ACPI_EC_CLASS);
 876
 877         /* Check for boot EC */
 878         if (boot_ec &&
 879             (boot_ec->handle == device->handle ||
 880              boot_ec->handle == ACPI_ROOT_OBJECT)) {
 881                 ec = boot_ec;
 882                 boot_ec = NULL;
 883         } else {
 884                 ec = make_acpi_ec();
 885                 if (!ec)
 886                         return -ENOMEM;
 887         }
 888         if (ec_parse_device(device->handle, 0, ec, NULL) !=
 889                 AE_CTRL_TERMINATE) {
 890                         kfree(ec);
 891                         return -EINVAL;
 892         }
 893
 894         ec->handle = device->handle;
 895
 896         /* Find and register all query methods */
 897         acpi_walk_namespace(ACPI_TYPE_METHOD, ec->handle, 1,
 898                             acpi_ec_register_query_methods, NULL, ec, NULL);
 899
 900         if (!first_ec)
 901                 first_ec = ec;
 902         device->driver_data = ec;
 903         acpi_ec_add_fs(device);
 904         pr_info(PREFIX "GPE = 0x%lx, I/O: command/status = 0x%lx, data = 0x%lx\n",
 905                           ec->gpe, ec->command_addr, ec->data_addr);
 906
 907         ret = ec_install_handlers(ec);
 908
 909         /* EC is fully operational, allow queries */
 910         clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags);
 911         return ret;
 912 }
 913
 914 static int acpi_ec_remove(struct acpi_device *device, int type)
 915 {
 916         struct acpi_ec *ec;
 917         struct acpi_ec_query_handler *handler, *tmp;
 918
 919         if (!device)
 920                 return -EINVAL;
 921
 922         ec = acpi_driver_data(device);
 923         ec_remove_handlers(ec);
 924         mutex_lock(&ec->lock);
 925         list_for_each_entry_safe(handler, tmp, &ec->list, node) {
 926                 list_del(&handler->node);
 927                 kfree(handler);
 928         }
 929         mutex_unlock(&ec->lock);
 930         acpi_ec_remove_fs(device);
 931         device->driver_data = NULL;
 932         if (ec == first_ec)
 933                 first_ec = NULL;
 934         kfree(ec);
 935         return 0;
 936 }
 937
 938 static acpi_status
 939 ec_parse_io_ports(struct acpi_resource *resource, void *context)
 940 {
 941         struct acpi_ec *ec = context;
 942
 943         if (resource->type != ACPI_RESOURCE_TYPE_IO)
 944                 return AE_OK;
 945
 946         /*
 947          * The first address region returned is the data port, and
 948          * the second address region returned is the status/command
 949          * port.
 950          */
 951         if (ec->data_addr == 0)
 952                 ec->data_addr = resource->data.io.minimum;
 953         else if (ec->command_addr == 0)
 954                 ec->command_addr = resource->data.io.minimum;
 955         else
 956                 return AE_CTRL_TERMINATE;
 957
 958         return AE_OK;
 959 }
 960
 961 int __init acpi_boot_ec_enable(void)
 962 {
 963         if (!boot_ec || test_bit(EC_FLAGS_HANDLERS_INSTALLED, &boot_ec->flags))
 964                 return 0;
 965         if (!ec_install_handlers(boot_ec)) {
 966                 first_ec = boot_ec;
 967                 return 0;
 968         }
 969         return -EFAULT;
 970 }
 971
 972 static const struct acpi_device_id ec_device_ids[] = {
 973         {"PNP0C09", 0},
 974         {"", 0},
 975 };
 976
 977 /* Some BIOS do not survive early DSDT scan, skip it */
 978 static int ec_skip_dsdt_scan(const struct dmi_system_id *id)
 979 {
 980         EC_FLAGS_SKIP_DSDT_SCAN = 1;
 981         return 0;
 982 }
 983
 984 /* ASUStek often supplies us with broken ECDT, validate it */
 985 static int ec_validate_ecdt(const struct dmi_system_id *id)
 986 {
 987         EC_FLAGS_VALIDATE_ECDT = 1;
 988         return 0;
 989 }
 990
 991 /* MSI EC needs special treatment, enable it */
 992 static int ec_flag_msi(const struct dmi_system_id *id)
 993 {
 994         printk(KERN_DEBUG PREFIX "Detected MSI hardware, enabling workarounds.\n");
 995         EC_FLAGS_MSI = 1;
 996         EC_FLAGS_VALIDATE_ECDT = 1;
 997         return 0;
 998 }
 999
1000 static struct dmi_system_id __initdata ec_dmi_table[] = {
1001         {
1002         ec_skip_dsdt_scan, "Compal JFL92", {
1003         DMI_MATCH(DMI_BIOS_VENDOR, "COMPAL"),
1004         DMI_MATCH(DMI_BOARD_NAME, "JFL92") }, NULL},
1005         {
1006         ec_flag_msi, "MSI hardware", {
1007         DMI_MATCH(DMI_BIOS_VENDOR, "Micro-Star")}, NULL},
1008         {
1009         ec_flag_msi, "MSI hardware", {
1010         DMI_MATCH(DMI_SYS_VENDOR, "Micro-Star")}, NULL},
1011         {
1012         ec_flag_msi, "MSI hardware", {
1013         DMI_MATCH(DMI_CHASSIS_VENDOR, "MICRO-Star")}, NULL},
1014         {
1015         ec_validate_ecdt, "ASUS hardware", {
1016         DMI_MATCH(DMI_BIOS_VENDOR, "ASUS") }, NULL},
1017         {},
1018 };
1019
1020
1021 int __init acpi_ec_ecdt_probe(void)
1022 {
1023         acpi_status status;
1024         struct acpi_ec *saved_ec = NULL;
1025         struct acpi_table_ecdt *ecdt_ptr;
1026
1027         boot_ec = make_acpi_ec();
1028         if (!boot_ec)
1029                 return -ENOMEM;
1030         /*
1031          * Generate a boot ec context
1032          */
1033         dmi_check_system(ec_dmi_table);
1034         status = acpi_get_table(ACPI_SIG_ECDT, 1,
1035                                 (struct acpi_table_header **)&ecdt_ptr);
1036         if (ACPI_SUCCESS(status)) {
1037                 pr_info(PREFIX "EC description table is found, configuring boot EC\n");
1038                 boot_ec->command_addr = ecdt_ptr->control.address;
1039                 boot_ec->data_addr = ecdt_ptr->data.address;
1040                 boot_ec->gpe = ecdt_ptr->gpe;
1041                 boot_ec->handle = ACPI_ROOT_OBJECT;
1042                 acpi_get_handle(ACPI_ROOT_OBJECT, ecdt_ptr->id, &boot_ec->handle);
1043                 /* Don't trust ECDT, which comes from ASUSTek */
1044                 if (!EC_FLAGS_VALIDATE_ECDT)
1045                         goto install;
1046                 saved_ec = kmalloc(sizeof(struct acpi_ec), GFP_KERNEL);
1047                 if (!saved_ec)
1048                         return -ENOMEM;
1049                 memcpy(saved_ec, boot_ec, sizeof(struct acpi_ec));
1050         /* fall through */
1051         }
1052
1053         if (EC_FLAGS_SKIP_DSDT_SCAN)
1054                 return -ENODEV;
1055
1056         /* This workaround is needed only on some broken machines,
1057          * which require early EC, but fail to provide ECDT */
1058         printk(KERN_DEBUG PREFIX "Look up EC in DSDT\n");
1059         status = acpi_get_devices(ec_device_ids[0].id, ec_parse_device,
1060                                         boot_ec, NULL);
1061         /* Check that acpi_get_devices actually find something */
1062         if (ACPI_FAILURE(status) || !boot_ec->handle)
1063                 goto error;
1064         if (saved_ec) {
1065                 /* try to find good ECDT from ASUSTek */
1066                 if (saved_ec->command_addr != boot_ec->command_addr ||
1067                     saved_ec->data_addr != boot_ec->data_addr ||
1068                     saved_ec->gpe != boot_ec->gpe ||
1069                     saved_ec->handle != boot_ec->handle)
1070                         pr_info(PREFIX "ASUSTek keeps feeding us with broken "
1071                         "ECDT tables, which are very hard to workaround. "
1072                         "Trying to use DSDT EC info instead. Please send "
1073                         "output of acpidump to linux-acpi@vger.kernel.org\n");
1074                 kfree(saved_ec);
1075                 saved_ec = NULL;
1076         } else {
1077                 /* We really need to limit this workaround, the only ASUS,
1078                 * which needs it, has fake EC._INI method, so use it as flag.
1079                 * Keep boot_ec struct as it will be needed soon.
1080                 */
1081                 acpi_handle dummy;
1082                 if (!dmi_name_in_vendors("ASUS") ||
1083                     ACPI_FAILURE(acpi_get_handle(boot_ec->handle, "_INI",
1084                                                         &dummy)))
1085                         return -ENODEV;
1086         }
1087 install:
1088         if (!ec_install_handlers(boot_ec)) {
1089                 first_ec = boot_ec;
1090                 return 0;
1091         }
1092 error:
1093         kfree(boot_ec);
1094         boot_ec = NULL;
1095         return -ENODEV;
1096 }
1097
1098 static int acpi_ec_suspend(struct acpi_device *device, pm_message_t state)
1099 {
1100         struct acpi_ec *ec = acpi_driver_data(device);
1101         /* Stop using the GPE, but keep it reference counted. */
1102         acpi_set_gpe(NULL, ec->gpe, ACPI_GPE_DISABLE);
1103         return 0;
1104 }
1105
1106 static int acpi_ec_resume(struct acpi_device *device)
1107 {
1108         struct acpi_ec *ec = acpi_driver_data(device);
1109         /* Enable the GPE again, but don't reference count it once more. */
1110         acpi_set_gpe(NULL, ec->gpe, ACPI_GPE_ENABLE);
1111         return 0;
1112 }
1113
1114 static struct acpi_driver acpi_ec_driver = {
1115         .name = "ec",
1116         .class = ACPI_EC_CLASS,
1117         .ids = ec_device_ids,
1118         .ops = {
1119                 .add = acpi_ec_add,
1120                 .remove = acpi_ec_remove,
1121                 .suspend = acpi_ec_suspend,
1122                 .resume = acpi_ec_resume,
1123                 },
1124 };
1125
1126 int __init acpi_ec_init(void)
1127 {
1128         int result = 0;
1129
1130         acpi_ec_dir = proc_mkdir(ACPI_EC_CLASS, acpi_root_dir);
1131         if (!acpi_ec_dir)
1132                 return -ENODEV;
1133
1134         /* Now register the driver for the EC */
1135         result = acpi_bus_register_driver(&acpi_ec_driver);
1136         if (result < 0) {
1137                 remove_proc_entry(ACPI_EC_CLASS, acpi_root_dir);
1138                 return -ENODEV;
1139         }
1140
1141         return result;
1142 }
1143
1144 /* EC driver currently not unloadable */
1145 #if 0
1146 static void __exit acpi_ec_exit(void)
1147 {
1148
1149         acpi_bus_unregister_driver(&acpi_ec_driver);
1150
1151         remove_proc_entry(ACPI_EC_CLASS, acpi_root_dir);
1152
1153         return;
1154 }
1155 #endif  /* 0 */