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/interrupt.h>
  38 #include <linux/list.h>
  39 #include <linux/spinlock.h>
  40 #include <linux/slab.h>
  41 #include <asm/io.h>
  42 #include <acpi/acpi_bus.h>
  43 #include <acpi/acpi_drivers.h>
  44 #include <linux/dmi.h>
  45
  46 #include "internal.h"
  47
  48 #define ACPI_EC_CLASS                   "embedded_controller"
  49 #define ACPI_EC_DEVICE_NAME             "Embedded Controller"
  50 #define ACPI_EC_FILE_INFO               "info"
  51
  52 #undef PREFIX
  53 #define PREFIX                          "ACPI: EC: "
  54
  55 /* EC status register */
  56 #define ACPI_EC_FLAG_OBF        0x01    /* Output buffer full */
  57 #define ACPI_EC_FLAG_IBF        0x02    /* Input buffer full */
  58 #define ACPI_EC_FLAG_BURST      0x10    /* burst mode */
  59 #define ACPI_EC_FLAG_SCI        0x20    /* EC-SCI occurred */
  60
  61 /* EC commands */
  62 enum ec_command {
  63         ACPI_EC_COMMAND_READ = 0x80,
  64         ACPI_EC_COMMAND_WRITE = 0x81,
  65         ACPI_EC_BURST_ENABLE = 0x82,
  66         ACPI_EC_BURST_DISABLE = 0x83,
  67         ACPI_EC_COMMAND_QUERY = 0x84,
  68 };
  69
  70 #define ACPI_EC_DELAY           500     /* Wait 500ms max. during EC ops */
  71 #define ACPI_EC_UDELAY_GLK      1000    /* Wait 1ms max. to get global lock */
  72 #define ACPI_EC_CDELAY          10      /* Wait 10us before polling EC */
  73 #define ACPI_EC_MSI_UDELAY      550     /* Wait 550us for MSI EC */
  74
  75 #define ACPI_EC_STORM_THRESHOLD 8       /* number of false interrupts
  76                                            per one transaction */
  77
  78 enum {
  79         EC_FLAGS_QUERY_PENDING,         /* Query is pending */
  80         EC_FLAGS_GPE_STORM,             /* GPE storm detected */
  81         EC_FLAGS_HANDLERS_INSTALLED,    /* Handlers for GPE and
  82                                          * OpReg are installed */
  83         EC_FLAGS_BLOCKED,               /* Transactions are blocked */
  84 };
  85
  86 /* ec.c is compiled in acpi namespace so this shows up as acpi.ec_delay param */
  87 static unsigned int ec_delay __read_mostly = ACPI_EC_DELAY;
  88 module_param(ec_delay, uint, 0644);
  89 MODULE_PARM_DESC(ec_delay, "Timeout(ms) waited until an EC command completes");
  90
  91 /* If we find an EC via the ECDT, we need to keep a ptr to its context */
  92 /* External interfaces use first EC only, so remember */
  93 typedef int (*acpi_ec_query_func) (void *data);
  94
  95 struct acpi_ec_query_handler {
  96         struct list_head node;
  97         acpi_ec_query_func func;
  98         acpi_handle handle;
  99         void *data;
 100         u8 query_bit;
 101 };
 102
 103 struct transaction {
 104         const u8 *wdata;
 105         u8 *rdata;
 106         unsigned short irq_count;
 107         u8 command;
 108         u8 wi;
 109         u8 ri;
 110         u8 wlen;
 111         u8 rlen;
 112         bool done;
 113 };
 114
 115 struct acpi_ec *boot_ec, *first_ec;
 116 EXPORT_SYMBOL(first_ec);
 117
 118 static int EC_FLAGS_MSI; /* Out-of-spec MSI controller */
 119 static int EC_FLAGS_VALIDATE_ECDT; /* ASUStec ECDTs need to be validated */
 120 static int EC_FLAGS_SKIP_DSDT_SCAN; /* Not all BIOS survive early DSDT scan */
 121
 122 /* --------------------------------------------------------------------------
 123                              Transaction Management
 124    -------------------------------------------------------------------------- */
 125
 126 static inline u8 acpi_ec_read_status(struct acpi_ec *ec)
 127 {
 128         u8 x = inb(ec->command_addr);
 129         pr_debug(PREFIX "---> status = 0x%2.2x\n", x);
 130         return x;
 131 }
 132
 133 static inline u8 acpi_ec_read_data(struct acpi_ec *ec)
 134 {
 135         u8 x = inb(ec->data_addr);
 136         pr_debug(PREFIX "---> data = 0x%2.2x\n", x);
 137         return x;
 138 }
 139
 140 static inline void acpi_ec_write_cmd(struct acpi_ec *ec, u8 command)
 141 {
 142         pr_debug(PREFIX "<--- command = 0x%2.2x\n", command);
 143         outb(command, ec->command_addr);
 144 }
 145
 146 static inline void acpi_ec_write_data(struct acpi_ec *ec, u8 data)
 147 {
 148         pr_debug(PREFIX "<--- data = 0x%2.2x\n", data);
 149         outb(data, ec->data_addr);
 150 }
 151
 152 static int ec_transaction_done(struct acpi_ec *ec)
 153 {
 154         unsigned long flags;
 155         int ret = 0;
 156         spin_lock_irqsave(&ec->curr_lock, flags);
 157         if (!ec->curr || ec->curr->done)
 158                 ret = 1;
 159         spin_unlock_irqrestore(&ec->curr_lock, flags);
 160         return ret;
 161 }
 162
 163 static void start_transaction(struct acpi_ec *ec)
 164 {
 165         ec->curr->irq_count = ec->curr->wi = ec->curr->ri = 0;
 166         ec->curr->done = false;
 167         acpi_ec_write_cmd(ec, ec->curr->command);
 168 }
 169
 170 static void advance_transaction(struct acpi_ec *ec, u8 status)
 171 {
 172         unsigned long flags;
 173         spin_lock_irqsave(&ec->curr_lock, flags);
 174         if (!ec->curr)
 175                 goto unlock;
 176         if (ec->curr->wlen > ec->curr->wi) {
 177                 if ((status & ACPI_EC_FLAG_IBF) == 0)
 178                         acpi_ec_write_data(ec,
 179                                 ec->curr->wdata[ec->curr->wi++]);
 180                 else
 181                         goto err;
 182         } else if (ec->curr->rlen > ec->curr->ri) {
 183                 if ((status & ACPI_EC_FLAG_OBF) == 1) {
 184                         ec->curr->rdata[ec->curr->ri++] = acpi_ec_read_data(ec);
 185                         if (ec->curr->rlen == ec->curr->ri)
 186                                 ec->curr->done = true;
 187                 } else
 188                         goto err;
 189         } else if (ec->curr->wlen == ec->curr->wi &&
 190                    (status & ACPI_EC_FLAG_IBF) == 0)
 191                 ec->curr->done = true;
 192         goto unlock;
 193 err:
 194         /* false interrupt, state didn't change */
 195         if (in_interrupt())
 196                 ++ec->curr->irq_count;
 197 unlock:
 198         spin_unlock_irqrestore(&ec->curr_lock, flags);
 199 }
 200
 201 static int acpi_ec_sync_query(struct acpi_ec *ec);
 202
 203 static int ec_check_sci_sync(struct acpi_ec *ec, u8 state)
 204 {
 205         if (state & ACPI_EC_FLAG_SCI) {
 206                 if (!test_and_set_bit(EC_FLAGS_QUERY_PENDING, &ec->flags))
 207                         return acpi_ec_sync_query(ec);
 208         }
 209         return 0;
 210 }
 211
 212 static int ec_poll(struct acpi_ec *ec)
 213 {
 214         unsigned long flags;
 215         int repeat = 2; /* number of command restarts */
 216         while (repeat--) {
 217                 unsigned long delay = jiffies +
 218                         msecs_to_jiffies(ec_delay);
 219                 do {
 220                         /* don't sleep with disabled interrupts */
 221                         if (EC_FLAGS_MSI || irqs_disabled()) {
 222                                 udelay(ACPI_EC_MSI_UDELAY);
 223                                 if (ec_transaction_done(ec))
 224                                         return 0;
 225                         } else {
 226                                 if (wait_event_timeout(ec->wait,
 227                                                 ec_transaction_done(ec),
 228                                                 msecs_to_jiffies(1)))
 229                                         return 0;
 230                         }
 231                         advance_transaction(ec, acpi_ec_read_status(ec));
 232                 } while (time_before(jiffies, delay));
 233                 if (acpi_ec_read_status(ec) & ACPI_EC_FLAG_IBF)
 234                         break;
 235                 pr_debug(PREFIX "controller reset, restart transaction\n");
 236                 spin_lock_irqsave(&ec->curr_lock, flags);
 237                 start_transaction(ec);
 238                 spin_unlock_irqrestore(&ec->curr_lock, flags);
 239         }
 240         return -ETIME;
 241 }
 242
 243 static int acpi_ec_transaction_unlocked(struct acpi_ec *ec,
 244                                         struct transaction *t)
 245 {
 246         unsigned long tmp;
 247         int ret = 0;
 248         if (EC_FLAGS_MSI)
 249                 udelay(ACPI_EC_MSI_UDELAY);
 250         /* start transaction */
 251         spin_lock_irqsave(&ec->curr_lock, tmp);
 252         /* following two actions should be kept atomic */
 253         ec->curr = t;
 254         start_transaction(ec);
 255         if (ec->curr->command == ACPI_EC_COMMAND_QUERY)
 256                 clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags);
 257         spin_unlock_irqrestore(&ec->curr_lock, tmp);
 258         ret = ec_poll(ec);
 259         spin_lock_irqsave(&ec->curr_lock, tmp);
 260         ec->curr = NULL;
 261         spin_unlock_irqrestore(&ec->curr_lock, tmp);
 262         return ret;
 263 }
 264
 265 static int ec_check_ibf0(struct acpi_ec *ec)
 266 {
 267         u8 status = acpi_ec_read_status(ec);
 268         return (status & ACPI_EC_FLAG_IBF) == 0;
 269 }
 270
 271 static int ec_wait_ibf0(struct acpi_ec *ec)
 272 {
 273         unsigned long delay = jiffies + msecs_to_jiffies(ec_delay);
 274         /* interrupt wait manually if GPE mode is not active */
 275         while (time_before(jiffies, delay))
 276                 if (wait_event_timeout(ec->wait, ec_check_ibf0(ec),
 277                                         msecs_to_jiffies(1)))
 278                         return 0;
 279         return -ETIME;
 280 }
 281
 282 static int acpi_ec_transaction(struct acpi_ec *ec, struct transaction *t)
 283 {
 284         int status;
 285         u32 glk;
 286         if (!ec || (!t) || (t->wlen && !t->wdata) || (t->rlen && !t->rdata))
 287                 return -EINVAL;
 288         if (t->rdata)
 289                 memset(t->rdata, 0, t->rlen);
 290         mutex_lock(&ec->lock);
 291         if (test_bit(EC_FLAGS_BLOCKED, &ec->flags)) {
 292                 status = -EINVAL;
 293                 goto unlock;
 294         }
 295         if (ec->global_lock) {
 296                 status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk);
 297                 if (ACPI_FAILURE(status)) {
 298                         status = -ENODEV;
 299                         goto unlock;
 300                 }
 301         }
 302         if (ec_wait_ibf0(ec)) {
 303                 pr_err(PREFIX "input buffer is not empty, "
 304                                 "aborting transaction\n");
 305                 status = -ETIME;
 306                 goto end;
 307         }
 308         pr_debug(PREFIX "transaction start\n");
 309         /* disable GPE during transaction if storm is detected */
 310         if (test_bit(EC_FLAGS_GPE_STORM, &ec->flags)) {
 311                 /* It has to be disabled, so that it doesn't trigger. */
 312                 acpi_disable_gpe(NULL, ec->gpe);
 313         }
 314
 315         status = acpi_ec_transaction_unlocked(ec, t);
 316
 317         /* check if we received SCI during transaction */
 318         ec_check_sci_sync(ec, acpi_ec_read_status(ec));
 319         if (test_bit(EC_FLAGS_GPE_STORM, &ec->flags)) {
 320                 msleep(1);
 321                 /* It is safe to enable the GPE outside of the transaction. */
 322                 acpi_enable_gpe(NULL, ec->gpe);
 323         } else if (t->irq_count > ACPI_EC_STORM_THRESHOLD) {
 324                 pr_info(PREFIX "GPE storm detected, "
 325                         "transactions will use polling mode\n");
 326                 set_bit(EC_FLAGS_GPE_STORM, &ec->flags);
 327         }
 328         pr_debug(PREFIX "transaction end\n");
 329 end:
 330         if (ec->global_lock)
 331                 acpi_release_global_lock(glk);
 332 unlock:
 333         mutex_unlock(&ec->lock);
 334         return status;
 335 }
 336
 337 static int acpi_ec_burst_enable(struct acpi_ec *ec)
 338 {
 339         u8 d;
 340         struct transaction t = {.command = ACPI_EC_BURST_ENABLE,
 341                                 .wdata = NULL, .rdata = &d,
 342                                 .wlen = 0, .rlen = 1};
 343
 344         return acpi_ec_transaction(ec, &t);
 345 }
 346
 347 static int acpi_ec_burst_disable(struct acpi_ec *ec)
 348 {
 349         struct transaction t = {.command = ACPI_EC_BURST_DISABLE,
 350                                 .wdata = NULL, .rdata = NULL,
 351                                 .wlen = 0, .rlen = 0};
 352
 353         return (acpi_ec_read_status(ec) & ACPI_EC_FLAG_BURST) ?
 354                                 acpi_ec_transaction(ec, &t) : 0;
 355 }
 356
 357 static int acpi_ec_read(struct acpi_ec *ec, u8 address, u8 * data)
 358 {
 359         int result;
 360         u8 d;
 361         struct transaction t = {.command = ACPI_EC_COMMAND_READ,
 362                                 .wdata = &address, .rdata = &d,
 363                                 .wlen = 1, .rlen = 1};
 364
 365         result = acpi_ec_transaction(ec, &t);
 366         *data = d;
 367         return result;
 368 }
 369
 370 static int acpi_ec_write(struct acpi_ec *ec, u8 address, u8 data)
 371 {
 372         u8 wdata[2] = { address, data };
 373         struct transaction t = {.command = ACPI_EC_COMMAND_WRITE,
 374                                 .wdata = wdata, .rdata = NULL,
 375                                 .wlen = 2, .rlen = 0};
 376
 377         return acpi_ec_transaction(ec, &t);
 378 }
 379
 380 /*
 381  * Externally callable EC access functions. For now, assume 1 EC only
 382  */
 383 int ec_burst_enable(void)
 384 {
 385         if (!first_ec)
 386                 return -ENODEV;
 387         return acpi_ec_burst_enable(first_ec);
 388 }
 389
 390 EXPORT_SYMBOL(ec_burst_enable);
 391
 392 int ec_burst_disable(void)
 393 {
 394         if (!first_ec)
 395                 return -ENODEV;
 396         return acpi_ec_burst_disable(first_ec);
 397 }
 398
 399 EXPORT_SYMBOL(ec_burst_disable);
 400
 401 int ec_read(u8 addr, u8 * val)
 402 {
 403         int err;
 404         u8 temp_data;
 405
 406         if (!first_ec)
 407                 return -ENODEV;
 408
 409         err = acpi_ec_read(first_ec, addr, &temp_data);
 410
 411         if (!err) {
 412                 *val = temp_data;
 413                 return 0;
 414         } else
 415                 return err;
 416 }
 417
 418 EXPORT_SYMBOL(ec_read);
 419
 420 int ec_write(u8 addr, u8 val)
 421 {
 422         int err;
 423
 424         if (!first_ec)
 425                 return -ENODEV;
 426
 427         err = acpi_ec_write(first_ec, addr, val);
 428
 429         return err;
 430 }
 431
 432 EXPORT_SYMBOL(ec_write);
 433
 434 int ec_transaction(u8 command,
 435                    const u8 * wdata, unsigned wdata_len,
 436                    u8 * rdata, unsigned rdata_len,
 437                    int force_poll)
 438 {
 439         struct transaction t = {.command = command,
 440                                 .wdata = wdata, .rdata = rdata,
 441                                 .wlen = wdata_len, .rlen = rdata_len};
 442         if (!first_ec)
 443                 return -ENODEV;
 444
 445         return acpi_ec_transaction(first_ec, &t);
 446 }
 447
 448 EXPORT_SYMBOL(ec_transaction);
 449
 450 void acpi_ec_block_transactions(void)
 451 {
 452         struct acpi_ec *ec = first_ec;
 453
 454         if (!ec)
 455                 return;
 456
 457         mutex_lock(&ec->lock);
 458         /* Prevent transactions from being carried out */
 459         set_bit(EC_FLAGS_BLOCKED, &ec->flags);
 460         mutex_unlock(&ec->lock);
 461 }
 462
 463 void acpi_ec_unblock_transactions(void)
 464 {
 465         struct acpi_ec *ec = first_ec;
 466
 467         if (!ec)
 468                 return;
 469
 470         mutex_lock(&ec->lock);
 471         /* Allow transactions to be carried out again */
 472         clear_bit(EC_FLAGS_BLOCKED, &ec->flags);
 473         mutex_unlock(&ec->lock);
 474 }
 475
 476 void acpi_ec_unblock_transactions_early(void)
 477 {
 478         /*
 479          * Allow transactions to happen again (this function is called from
 480          * atomic context during wakeup, so we don't need to acquire the mutex).
 481          */
 482         if (first_ec)
 483                 clear_bit(EC_FLAGS_BLOCKED, &first_ec->flags);
 484 }
 485
 486 static int acpi_ec_query_unlocked(struct acpi_ec *ec, u8 * data)
 487 {
 488         int result;
 489         u8 d;
 490         struct transaction t = {.command = ACPI_EC_COMMAND_QUERY,
 491                                 .wdata = NULL, .rdata = &d,
 492                                 .wlen = 0, .rlen = 1};
 493         if (!ec || !data)
 494                 return -EINVAL;
 495         /*
 496          * Query the EC to find out which _Qxx method we need to evaluate.
 497          * Note that successful completion of the query causes the ACPI_EC_SCI
 498          * bit to be cleared (and thus clearing the interrupt source).
 499          */
 500         result = acpi_ec_transaction_unlocked(ec, &t);
 501         if (result)
 502                 return result;
 503         if (!d)
 504                 return -ENODATA;
 505         *data = d;
 506         return 0;
 507 }
 508
 509 /* --------------------------------------------------------------------------
 510                                 Event Management
 511    -------------------------------------------------------------------------- */
 512 int acpi_ec_add_query_handler(struct acpi_ec *ec, u8 query_bit,
 513                               acpi_handle handle, acpi_ec_query_func func,
 514                               void *data)
 515 {
 516         struct acpi_ec_query_handler *handler =
 517             kzalloc(sizeof(struct acpi_ec_query_handler), GFP_KERNEL);
 518         if (!handler)
 519                 return -ENOMEM;
 520
 521         handler->query_bit = query_bit;
 522         handler->handle = handle;
 523         handler->func = func;
 524         handler->data = data;
 525         mutex_lock(&ec->lock);
 526         list_add(&handler->node, &ec->list);
 527         mutex_unlock(&ec->lock);
 528         return 0;
 529 }
 530
 531 EXPORT_SYMBOL_GPL(acpi_ec_add_query_handler);
 532
 533 void acpi_ec_remove_query_handler(struct acpi_ec *ec, u8 query_bit)
 534 {
 535         struct acpi_ec_query_handler *handler, *tmp;
 536         mutex_lock(&ec->lock);
 537         list_for_each_entry_safe(handler, tmp, &ec->list, node) {
 538                 if (query_bit == handler->query_bit) {
 539                         list_del(&handler->node);
 540                         kfree(handler);
 541                 }
 542         }
 543         mutex_unlock(&ec->lock);
 544 }
 545
 546 EXPORT_SYMBOL_GPL(acpi_ec_remove_query_handler);
 547
 548 static void acpi_ec_run(void *cxt)
 549 {
 550         struct acpi_ec_query_handler *handler = cxt;
 551         if (!handler)
 552                 return;
 553         pr_debug(PREFIX "start query execution\n");
 554         if (handler->func)
 555                 handler->func(handler->data);
 556         else if (handler->handle)
 557                 acpi_evaluate_object(handler->handle, NULL, NULL, NULL);
 558         pr_debug(PREFIX "stop query execution\n");
 559         kfree(handler);
 560 }
 561
 562 static int acpi_ec_sync_query(struct acpi_ec *ec)
 563 {
 564         u8 value = 0;
 565         int status;
 566         struct acpi_ec_query_handler *handler, *copy;
 567         if ((status = acpi_ec_query_unlocked(ec, &value)))
 568                 return status;
 569         list_for_each_entry(handler, &ec->list, node) {
 570                 if (value == handler->query_bit) {
 571                         /* have custom handler for this bit */
 572                         copy = kmalloc(sizeof(*handler), GFP_KERNEL);
 573                         if (!copy)
 574                                 return -ENOMEM;
 575                         memcpy(copy, handler, sizeof(*copy));
 576                         pr_debug(PREFIX "push query execution (0x%2x) on queue\n", value);
 577                         return acpi_os_execute((copy->func) ?
 578                                 OSL_NOTIFY_HANDLER : OSL_GPE_HANDLER,
 579                                 acpi_ec_run, copy);
 580                 }
 581         }
 582         return 0;
 583 }
 584
 585 static void acpi_ec_gpe_query(void *ec_cxt)
 586 {
 587         struct acpi_ec *ec = ec_cxt;
 588         if (!ec)
 589                 return;
 590         mutex_lock(&ec->lock);
 591         acpi_ec_sync_query(ec);
 592         mutex_unlock(&ec->lock);
 593 }
 594
 595 static void acpi_ec_gpe_query(void *ec_cxt);
 596
 597 static int ec_check_sci(struct acpi_ec *ec, u8 state)
 598 {
 599         if (state & ACPI_EC_FLAG_SCI) {
 600                 if (!test_and_set_bit(EC_FLAGS_QUERY_PENDING, &ec->flags)) {
 601                         pr_debug(PREFIX "push gpe query to the queue\n");
 602                         return acpi_os_execute(OSL_NOTIFY_HANDLER,
 603                                 acpi_ec_gpe_query, ec);
 604                 }
 605         }
 606         return 0;
 607 }
 608
 609 static u32 acpi_ec_gpe_handler(acpi_handle gpe_device,
 610         u32 gpe_number, 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 | ACPI_REENABLE_GPE;
 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 *value64,
 632                       void *handler_context, void *region_context)
 633 {
 634         struct acpi_ec *ec = handler_context;
 635         int result = 0, i, bytes = bits / 8;
 636         u8 *value = (u8 *)value64;
 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 (EC_FLAGS_MSI || bits > 8)
 645                 acpi_ec_burst_enable(ec);
 646
 647         for (i = 0; i < bytes; ++i, ++address, ++value)
 648                 result = (function == ACPI_READ) ?
 649                         acpi_ec_read(ec, address, value) :
 650                         acpi_ec_write(ec, address, *value);
 651
 652         if (EC_FLAGS_MSI || bits > 8)
 653                 acpi_ec_burst_disable(ec);
 654
 655         switch (result) {
 656         case -EINVAL:
 657                 return AE_BAD_PARAMETER;
 658                 break;
 659         case -ENODEV:
 660                 return AE_NOT_FOUND;
 661                 break;
 662         case -ETIME:
 663                 return AE_TIME;
 664                 break;
 665         default:
 666                 return AE_OK;
 667         }
 668 }
 669
 670 /* --------------------------------------------------------------------------
 671                                Driver Interface
 672    -------------------------------------------------------------------------- */
 673 static acpi_status
 674 ec_parse_io_ports(struct acpi_resource *resource, void *context);
 675
 676 static struct acpi_ec *make_acpi_ec(void)
 677 {
 678         struct acpi_ec *ec = kzalloc(sizeof(struct acpi_ec), GFP_KERNEL);
 679         if (!ec)
 680                 return NULL;
 681         ec->flags = 1 << EC_FLAGS_QUERY_PENDING;
 682         mutex_init(&ec->lock);
 683         init_waitqueue_head(&ec->wait);
 684         INIT_LIST_HEAD(&ec->list);
 685         spin_lock_init(&ec->curr_lock);
 686         return ec;
 687 }
 688
 689 static acpi_status
 690 acpi_ec_register_query_methods(acpi_handle handle, u32 level,
 691                                void *context, void **return_value)
 692 {
 693         char node_name[5];
 694         struct acpi_buffer buffer = { sizeof(node_name), node_name };
 695         struct acpi_ec *ec = context;
 696         int value = 0;
 697         acpi_status status;
 698
 699         status = acpi_get_name(handle, ACPI_SINGLE_NAME, &buffer);
 700
 701         if (ACPI_SUCCESS(status) && sscanf(node_name, "_Q%x", &value) == 1) {
 702                 acpi_ec_add_query_handler(ec, value, handle, NULL, NULL);
 703         }
 704         return AE_OK;
 705 }
 706
 707 static acpi_status
 708 ec_parse_device(acpi_handle handle, u32 Level, void *context, void **retval)
 709 {
 710         acpi_status status;
 711         unsigned long long tmp = 0;
 712
 713         struct acpi_ec *ec = context;
 714
 715         /* clear addr values, ec_parse_io_ports depend on it */
 716         ec->command_addr = ec->data_addr = 0;
 717
 718         status = acpi_walk_resources(handle, METHOD_NAME__CRS,
 719                                      ec_parse_io_ports, ec);
 720         if (ACPI_FAILURE(status))
 721                 return status;
 722
 723         /* Get GPE bit assignment (EC events). */
 724         /* TODO: Add support for _GPE returning a package */
 725         status = acpi_evaluate_integer(handle, "_GPE", NULL, &tmp);
 726         if (ACPI_FAILURE(status))
 727                 return status;
 728         ec->gpe = tmp;
 729         /* Use the global lock for all EC transactions? */
 730         tmp = 0;
 731         acpi_evaluate_integer(handle, "_GLK", NULL, &tmp);
 732         ec->global_lock = tmp;
 733         ec->handle = handle;
 734         return AE_CTRL_TERMINATE;
 735 }
 736
 737 static int ec_install_handlers(struct acpi_ec *ec)
 738 {
 739         acpi_status status;
 740         if (test_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags))
 741                 return 0;
 742         status = acpi_install_gpe_handler(NULL, ec->gpe,
 743                                   ACPI_GPE_EDGE_TRIGGERED,
 744                                   &acpi_ec_gpe_handler, ec);
 745         if (ACPI_FAILURE(status))
 746                 return -ENODEV;
 747
 748         acpi_enable_gpe(NULL, ec->gpe);
 749         status = acpi_install_address_space_handler(ec->handle,
 750                                                     ACPI_ADR_SPACE_EC,
 751                                                     &acpi_ec_space_handler,
 752                                                     NULL, ec);
 753         if (ACPI_FAILURE(status)) {
 754                 if (status == AE_NOT_FOUND) {
 755                         /*
 756                          * Maybe OS fails in evaluating the _REG object.
 757                          * The AE_NOT_FOUND error will be ignored and OS
 758                          * continue to initialize EC.
 759                          */
 760                         printk(KERN_ERR "Fail in evaluating the _REG object"
 761                                 " of EC device. Broken bios is suspected.\n");
 762                 } else {
 763                         acpi_remove_gpe_handler(NULL, ec->gpe,
 764                                 &acpi_ec_gpe_handler);
 765                         acpi_disable_gpe(NULL, ec->gpe);
 766                         return -ENODEV;
 767                 }
 768         }
 769
 770         set_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags);
 771         return 0;
 772 }
 773
 774 static void ec_remove_handlers(struct acpi_ec *ec)
 775 {
 776         acpi_disable_gpe(NULL, ec->gpe);
 777         if (ACPI_FAILURE(acpi_remove_address_space_handler(ec->handle,
 778                                 ACPI_ADR_SPACE_EC, &acpi_ec_space_handler)))
 779                 pr_err(PREFIX "failed to remove space handler\n");
 780         if (ACPI_FAILURE(acpi_remove_gpe_handler(NULL, ec->gpe,
 781                                 &acpi_ec_gpe_handler)))
 782                 pr_err(PREFIX "failed to remove gpe handler\n");
 783         clear_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags);
 784 }
 785
 786 static int acpi_ec_add(struct acpi_device *device)
 787 {
 788         struct acpi_ec *ec = NULL;
 789         int ret;
 790
 791         strcpy(acpi_device_name(device), ACPI_EC_DEVICE_NAME);
 792         strcpy(acpi_device_class(device), ACPI_EC_CLASS);
 793
 794         /* Check for boot EC */
 795         if (boot_ec &&
 796             (boot_ec->handle == device->handle ||
 797              boot_ec->handle == ACPI_ROOT_OBJECT)) {
 798                 ec = boot_ec;
 799                 boot_ec = NULL;
 800         } else {
 801                 ec = make_acpi_ec();
 802                 if (!ec)
 803                         return -ENOMEM;
 804         }
 805         if (ec_parse_device(device->handle, 0, ec, NULL) !=
 806                 AE_CTRL_TERMINATE) {
 807                         kfree(ec);
 808                         return -EINVAL;
 809         }
 810
 811         ec->handle = device->handle;
 812
 813         /* Find and register all query methods */
 814         acpi_walk_namespace(ACPI_TYPE_METHOD, ec->handle, 1,
 815                             acpi_ec_register_query_methods, NULL, ec, NULL);
 816
 817         if (!first_ec)
 818                 first_ec = ec;
 819         device->driver_data = ec;
 820
 821         WARN(!request_region(ec->data_addr, 1, "EC data"),
 822              "Could not request EC data io port 0x%lx", ec->data_addr);
 823         WARN(!request_region(ec->command_addr, 1, "EC cmd"),
 824              "Could not request EC cmd io port 0x%lx", ec->command_addr);
 825
 826         pr_info(PREFIX "GPE = 0x%lx, I/O: command/status = 0x%lx, data = 0x%lx\n",
 827                           ec->gpe, ec->command_addr, ec->data_addr);
 828
 829         ret = ec_install_handlers(ec);
 830
 831         /* EC is fully operational, allow queries */
 832         clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags);
 833         return ret;
 834 }
 835
 836 static int acpi_ec_remove(struct acpi_device *device, int type)
 837 {
 838         struct acpi_ec *ec;
 839         struct acpi_ec_query_handler *handler, *tmp;
 840
 841         if (!device)
 842                 return -EINVAL;
 843
 844         ec = acpi_driver_data(device);
 845         ec_remove_handlers(ec);
 846         mutex_lock(&ec->lock);
 847         list_for_each_entry_safe(handler, tmp, &ec->list, node) {
 848                 list_del(&handler->node);
 849                 kfree(handler);
 850         }
 851         mutex_unlock(&ec->lock);
 852         release_region(ec->data_addr, 1);
 853         release_region(ec->command_addr, 1);
 854         device->driver_data = NULL;
 855         if (ec == first_ec)
 856                 first_ec = NULL;
 857         kfree(ec);
 858         return 0;
 859 }
 860
 861 static acpi_status
 862 ec_parse_io_ports(struct acpi_resource *resource, void *context)
 863 {
 864         struct acpi_ec *ec = context;
 865
 866         if (resource->type != ACPI_RESOURCE_TYPE_IO)
 867                 return AE_OK;
 868
 869         /*
 870          * The first address region returned is the data port, and
 871          * the second address region returned is the status/command
 872          * port.
 873          */
 874         if (ec->data_addr == 0)
 875                 ec->data_addr = resource->data.io.minimum;
 876         else if (ec->command_addr == 0)
 877                 ec->command_addr = resource->data.io.minimum;
 878         else
 879                 return AE_CTRL_TERMINATE;
 880
 881         return AE_OK;
 882 }
 883
 884 int __init acpi_boot_ec_enable(void)
 885 {
 886         if (!boot_ec || test_bit(EC_FLAGS_HANDLERS_INSTALLED, &boot_ec->flags))
 887                 return 0;
 888         if (!ec_install_handlers(boot_ec)) {
 889                 first_ec = boot_ec;
 890                 return 0;
 891         }
 892         return -EFAULT;
 893 }
 894
 895 static const struct acpi_device_id ec_device_ids[] = {
 896         {"PNP0C09", 0},
 897         {"", 0},
 898 };
 899
 900 /* Some BIOS do not survive early DSDT scan, skip it */
 901 static int ec_skip_dsdt_scan(const struct dmi_system_id *id)
 902 {
 903         EC_FLAGS_SKIP_DSDT_SCAN = 1;
 904         return 0;
 905 }
 906
 907 /* ASUStek often supplies us with broken ECDT, validate it */
 908 static int ec_validate_ecdt(const struct dmi_system_id *id)
 909 {
 910         EC_FLAGS_VALIDATE_ECDT = 1;
 911         return 0;
 912 }
 913
 914 /* MSI EC needs special treatment, enable it */
 915 static int ec_flag_msi(const struct dmi_system_id *id)
 916 {
 917         printk(KERN_DEBUG PREFIX "Detected MSI hardware, enabling workarounds.\n");
 918         EC_FLAGS_MSI = 1;
 919         EC_FLAGS_VALIDATE_ECDT = 1;
 920         return 0;
 921 }
 922
 923 static struct dmi_system_id __initdata ec_dmi_table[] = {
 924         {
 925         ec_skip_dsdt_scan, "Compal JFL92", {
 926         DMI_MATCH(DMI_BIOS_VENDOR, "COMPAL"),
 927         DMI_MATCH(DMI_BOARD_NAME, "JFL92") }, NULL},
 928         {
 929         ec_flag_msi, "MSI hardware", {
 930         DMI_MATCH(DMI_BIOS_VENDOR, "Micro-Star")}, NULL},
 931         {
 932         ec_flag_msi, "MSI hardware", {
 933         DMI_MATCH(DMI_SYS_VENDOR, "Micro-Star")}, NULL},
 934         {
 935         ec_flag_msi, "MSI hardware", {
 936         DMI_MATCH(DMI_CHASSIS_VENDOR, "MICRO-Star")}, NULL},
 937         {
 938         ec_flag_msi, "MSI hardware", {
 939         DMI_MATCH(DMI_CHASSIS_VENDOR, "MICRO-STAR")}, NULL},
 940         {
 941         ec_validate_ecdt, "ASUS hardware", {
 942         DMI_MATCH(DMI_BIOS_VENDOR, "ASUS") }, NULL},
 943         {},
 944 };
 945
 946
 947 int __init acpi_ec_ecdt_probe(void)
 948 {
 949         acpi_status status;
 950         struct acpi_ec *saved_ec = NULL;
 951         struct acpi_table_ecdt *ecdt_ptr;
 952
 953         boot_ec = make_acpi_ec();
 954         if (!boot_ec)
 955                 return -ENOMEM;
 956         /*
 957          * Generate a boot ec context
 958          */
 959         dmi_check_system(ec_dmi_table);
 960         status = acpi_get_table(ACPI_SIG_ECDT, 1,
 961                                 (struct acpi_table_header **)&ecdt_ptr);
 962         if (ACPI_SUCCESS(status)) {
 963                 pr_info(PREFIX "EC description table is found, configuring boot EC\n");
 964                 boot_ec->command_addr = ecdt_ptr->control.address;
 965                 boot_ec->data_addr = ecdt_ptr->data.address;
 966                 boot_ec->gpe = ecdt_ptr->gpe;
 967                 boot_ec->handle = ACPI_ROOT_OBJECT;
 968                 acpi_get_handle(ACPI_ROOT_OBJECT, ecdt_ptr->id, &boot_ec->handle);
 969                 /* Don't trust ECDT, which comes from ASUSTek */
 970                 if (!EC_FLAGS_VALIDATE_ECDT)
 971                         goto install;
 972                 saved_ec = kmemdup(boot_ec, sizeof(struct acpi_ec), GFP_KERNEL);
 973                 if (!saved_ec)
 974                         return -ENOMEM;
 975         /* fall through */
 976         }
 977
 978         if (EC_FLAGS_SKIP_DSDT_SCAN)
 979                 return -ENODEV;
 980
 981         /* This workaround is needed only on some broken machines,
 982          * which require early EC, but fail to provide ECDT */
 983         printk(KERN_DEBUG PREFIX "Look up EC in DSDT\n");
 984         status = acpi_get_devices(ec_device_ids[0].id, ec_parse_device,
 985                                         boot_ec, NULL);
 986         /* Check that acpi_get_devices actually find something */
 987         if (ACPI_FAILURE(status) || !boot_ec->handle)
 988                 goto error;
 989         if (saved_ec) {
 990                 /* try to find good ECDT from ASUSTek */
 991                 if (saved_ec->command_addr != boot_ec->command_addr ||
 992                     saved_ec->data_addr != boot_ec->data_addr ||
 993                     saved_ec->gpe != boot_ec->gpe ||
 994                     saved_ec->handle != boot_ec->handle)
 995                         pr_info(PREFIX "ASUSTek keeps feeding us with broken "
 996                         "ECDT tables, which are very hard to workaround. "
 997                         "Trying to use DSDT EC info instead. Please send "
 998                         "output of acpidump to linux-acpi@vger.kernel.org\n");
 999                 kfree(saved_ec);
1000                 saved_ec = NULL;
1001         } else {
1002                 /* We really need to limit this workaround, the only ASUS,
1003                 * which needs it, has fake EC._INI method, so use it as flag.
1004                 * Keep boot_ec struct as it will be needed soon.
1005                 */
1006                 acpi_handle dummy;
1007                 if (!dmi_name_in_vendors("ASUS") ||
1008                     ACPI_FAILURE(acpi_get_handle(boot_ec->handle, "_INI",
1009                                                         &dummy)))
1010                         return -ENODEV;
1011         }
1012 install:
1013         if (!ec_install_handlers(boot_ec)) {
1014                 first_ec = boot_ec;
1015                 return 0;
1016         }
1017 error:
1018         kfree(boot_ec);
1019         boot_ec = NULL;
1020         return -ENODEV;
1021 }
1022
1023 static struct acpi_driver acpi_ec_driver = {
1024         .name = "ec",
1025         .class = ACPI_EC_CLASS,
1026         .ids = ec_device_ids,
1027         .ops = {
1028                 .add = acpi_ec_add,
1029                 .remove = acpi_ec_remove,
1030                 },
1031 };
1032
1033 int __init acpi_ec_init(void)
1034 {
1035         int result = 0;
1036
1037         /* Now register the driver for the EC */
1038         result = acpi_bus_register_driver(&acpi_ec_driver);
1039         if (result < 0)
1040                 return -ENODEV;
1041
1042         return result;
1043 }
1044
1045 /* EC driver currently not unloadable */
1046 #if 0
1047 static void __exit acpi_ec_exit(void)
1048 {
1049
1050         acpi_bus_unregister_driver(&acpi_ec_driver);
1051         return;
1052 }
1053 #endif  /* 0 */