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_MSI_UDELAY      550     /* Wait 550us for MSI EC */
  73
  74 enum {
  75         EC_FLAGS_QUERY_PENDING,         /* Query is pending */
  76         EC_FLAGS_GPE_STORM,             /* GPE storm detected */
  77         EC_FLAGS_HANDLERS_INSTALLED,    /* Handlers for GPE and
  78                                          * OpReg are installed */
  79         EC_FLAGS_BLOCKED,               /* Transactions are blocked */
  80 };
  81
  82 /* ec.c is compiled in acpi namespace so this shows up as acpi.ec_delay param */
  83 static unsigned int ec_delay __read_mostly = ACPI_EC_DELAY;
  84 module_param(ec_delay, uint, 0644);
  85 MODULE_PARM_DESC(ec_delay, "Timeout(ms) waited until an EC command completes");
  86
  87 /*
  88  * If the number of false interrupts per one transaction exceeds
  89  * this threshold, will think there is a GPE storm happened and
  90  * will disable the GPE for normal transaction.
  91  */
  92 static unsigned int ec_storm_threshold  __read_mostly = 8;
  93 module_param(ec_storm_threshold, uint, 0644);
  94 MODULE_PARM_DESC(ec_storm_threshold, "Maxim false GPE numbers not considered as GPE storm");
  95
  96 /* If we find an EC via the ECDT, we need to keep a ptr to its context */
  97 /* External interfaces use first EC only, so remember */
  98 typedef int (*acpi_ec_query_func) (void *data);
  99
 100 struct acpi_ec_query_handler {
 101         struct list_head node;
 102         acpi_ec_query_func func;
 103         acpi_handle handle;
 104         void *data;
 105         u8 query_bit;
 106 };
 107
 108 struct transaction {
 109         const u8 *wdata;
 110         u8 *rdata;
 111         unsigned short irq_count;
 112         u8 command;
 113         u8 wi;
 114         u8 ri;
 115         u8 wlen;
 116         u8 rlen;
 117         bool done;
 118 };
 119
 120 struct acpi_ec *boot_ec, *first_ec;
 121 EXPORT_SYMBOL(first_ec);
 122
 123 static int EC_FLAGS_MSI; /* Out-of-spec MSI controller */
 124 static int EC_FLAGS_VALIDATE_ECDT; /* ASUStec ECDTs need to be validated */
 125 static int EC_FLAGS_SKIP_DSDT_SCAN; /* Not all BIOS survive early DSDT scan */
 126
 127 /* --------------------------------------------------------------------------
 128                              Transaction Management
 129    -------------------------------------------------------------------------- */
 130
 131 static inline u8 acpi_ec_read_status(struct acpi_ec *ec)
 132 {
 133         u8 x = inb(ec->command_addr);
 134         pr_debug(PREFIX "---> status = 0x%2.2x\n", x);
 135         return x;
 136 }
 137
 138 static inline u8 acpi_ec_read_data(struct acpi_ec *ec)
 139 {
 140         u8 x = inb(ec->data_addr);
 141         pr_debug(PREFIX "---> data = 0x%2.2x\n", x);
 142         return x;
 143 }
 144
 145 static inline void acpi_ec_write_cmd(struct acpi_ec *ec, u8 command)
 146 {
 147         pr_debug(PREFIX "<--- command = 0x%2.2x\n", command);
 148         outb(command, ec->command_addr);
 149 }
 150
 151 static inline void acpi_ec_write_data(struct acpi_ec *ec, u8 data)
 152 {
 153         pr_debug(PREFIX "<--- data = 0x%2.2x\n", data);
 154         outb(data, ec->data_addr);
 155 }
 156
 157 static int ec_transaction_done(struct acpi_ec *ec)
 158 {
 159         unsigned long flags;
 160         int ret = 0;
 161         spin_lock_irqsave(&ec->curr_lock, flags);
 162         if (!ec->curr || ec->curr->done)
 163                 ret = 1;
 164         spin_unlock_irqrestore(&ec->curr_lock, flags);
 165         return ret;
 166 }
 167
 168 static void start_transaction(struct acpi_ec *ec)
 169 {
 170         ec->curr->irq_count = ec->curr->wi = ec->curr->ri = 0;
 171         ec->curr->done = false;
 172         acpi_ec_write_cmd(ec, ec->curr->command);
 173 }
 174
 175 static void advance_transaction(struct acpi_ec *ec, u8 status)
 176 {
 177         unsigned long flags;
 178         spin_lock_irqsave(&ec->curr_lock, flags);
 179         if (!ec->curr)
 180                 goto unlock;
 181         if (ec->curr->wlen > ec->curr->wi) {
 182                 if ((status & ACPI_EC_FLAG_IBF) == 0)
 183                         acpi_ec_write_data(ec,
 184                                 ec->curr->wdata[ec->curr->wi++]);
 185                 else
 186                         goto err;
 187         } else if (ec->curr->rlen > ec->curr->ri) {
 188                 if ((status & ACPI_EC_FLAG_OBF) == 1) {
 189                         ec->curr->rdata[ec->curr->ri++] = acpi_ec_read_data(ec);
 190                         if (ec->curr->rlen == ec->curr->ri)
 191                                 ec->curr->done = true;
 192                 } else
 193                         goto err;
 194         } else if (ec->curr->wlen == ec->curr->wi &&
 195                    (status & ACPI_EC_FLAG_IBF) == 0)
 196                 ec->curr->done = true;
 197         goto unlock;
 198 err:
 199         /* false interrupt, state didn't change */
 200         if (in_interrupt())
 201                 ++ec->curr->irq_count;
 202 unlock:
 203         spin_unlock_irqrestore(&ec->curr_lock, flags);
 204 }
 205
 206 static int acpi_ec_sync_query(struct acpi_ec *ec);
 207
 208 static int ec_check_sci_sync(struct acpi_ec *ec, u8 state)
 209 {
 210         if (state & ACPI_EC_FLAG_SCI) {
 211                 if (!test_and_set_bit(EC_FLAGS_QUERY_PENDING, &ec->flags))
 212                         return acpi_ec_sync_query(ec);
 213         }
 214         return 0;
 215 }
 216
 217 static int ec_poll(struct acpi_ec *ec)
 218 {
 219         unsigned long flags;
 220         int repeat = 5; /* number of command restarts */
 221         while (repeat--) {
 222                 unsigned long delay = jiffies +
 223                         msecs_to_jiffies(ec_delay);
 224                 do {
 225                         /* don't sleep with disabled interrupts */
 226                         if (EC_FLAGS_MSI || irqs_disabled()) {
 227                                 udelay(ACPI_EC_MSI_UDELAY);
 228                                 if (ec_transaction_done(ec))
 229                                         return 0;
 230                         } else {
 231                                 if (wait_event_timeout(ec->wait,
 232                                                 ec_transaction_done(ec),
 233                                                 msecs_to_jiffies(1)))
 234                                         return 0;
 235                         }
 236                         advance_transaction(ec, acpi_ec_read_status(ec));
 237                 } while (time_before(jiffies, delay));
 238                 pr_debug(PREFIX "controller reset, restart transaction\n");
 239                 spin_lock_irqsave(&ec->curr_lock, flags);
 240                 start_transaction(ec);
 241                 spin_unlock_irqrestore(&ec->curr_lock, flags);
 242         }
 243         return -ETIME;
 244 }
 245
 246 static int acpi_ec_transaction_unlocked(struct acpi_ec *ec,
 247                                         struct transaction *t)
 248 {
 249         unsigned long tmp;
 250         int ret = 0;
 251         if (EC_FLAGS_MSI)
 252                 udelay(ACPI_EC_MSI_UDELAY);
 253         /* start transaction */
 254         spin_lock_irqsave(&ec->curr_lock, tmp);
 255         /* following two actions should be kept atomic */
 256         ec->curr = t;
 257         start_transaction(ec);
 258         if (ec->curr->command == ACPI_EC_COMMAND_QUERY)
 259                 clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags);
 260         spin_unlock_irqrestore(&ec->curr_lock, tmp);
 261         ret = ec_poll(ec);
 262         spin_lock_irqsave(&ec->curr_lock, tmp);
 263         ec->curr = NULL;
 264         spin_unlock_irqrestore(&ec->curr_lock, tmp);
 265         return ret;
 266 }
 267
 268 static int ec_check_ibf0(struct acpi_ec *ec)
 269 {
 270         u8 status = acpi_ec_read_status(ec);
 271         return (status & ACPI_EC_FLAG_IBF) == 0;
 272 }
 273
 274 static int ec_wait_ibf0(struct acpi_ec *ec)
 275 {
 276         unsigned long delay = jiffies + msecs_to_jiffies(ec_delay);
 277         /* interrupt wait manually if GPE mode is not active */
 278         while (time_before(jiffies, delay))
 279                 if (wait_event_timeout(ec->wait, ec_check_ibf0(ec),
 280                                         msecs_to_jiffies(1)))
 281                         return 0;
 282         return -ETIME;
 283 }
 284
 285 static int acpi_ec_transaction(struct acpi_ec *ec, struct transaction *t)
 286 {
 287         int status;
 288         u32 glk;
 289         if (!ec || (!t) || (t->wlen && !t->wdata) || (t->rlen && !t->rdata))
 290                 return -EINVAL;
 291         if (t->rdata)
 292                 memset(t->rdata, 0, t->rlen);
 293         mutex_lock(&ec->lock);
 294         if (test_bit(EC_FLAGS_BLOCKED, &ec->flags)) {
 295                 status = -EINVAL;
 296                 goto unlock;
 297         }
 298         if (ec->global_lock) {
 299                 status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk);
 300                 if (ACPI_FAILURE(status)) {
 301                         status = -ENODEV;
 302                         goto unlock;
 303                 }
 304         }
 305         if (ec_wait_ibf0(ec)) {
 306                 pr_err(PREFIX "input buffer is not empty, "
 307                                 "aborting transaction\n");
 308                 status = -ETIME;
 309                 goto end;
 310         }
 311         pr_debug(PREFIX "transaction start\n");
 312         /* disable GPE during transaction if storm is detected */
 313         if (test_bit(EC_FLAGS_GPE_STORM, &ec->flags)) {
 314                 /* It has to be disabled, so that it doesn't trigger. */
 315                 acpi_disable_gpe(NULL, ec->gpe);
 316         }
 317
 318         status = acpi_ec_transaction_unlocked(ec, t);
 319
 320         /* check if we received SCI during transaction */
 321         ec_check_sci_sync(ec, acpi_ec_read_status(ec));
 322         if (test_bit(EC_FLAGS_GPE_STORM, &ec->flags)) {
 323                 msleep(1);
 324                 /* It is safe to enable the GPE outside of the transaction. */
 325                 acpi_enable_gpe(NULL, ec->gpe);
 326         } else if (t->irq_count > ec_storm_threshold) {
 327                 pr_info(PREFIX "GPE storm detected, "
 328                         "transactions will use polling mode\n");
 329                 set_bit(EC_FLAGS_GPE_STORM, &ec->flags);
 330         }
 331         pr_debug(PREFIX "transaction end\n");
 332 end:
 333         if (ec->global_lock)
 334                 acpi_release_global_lock(glk);
 335 unlock:
 336         mutex_unlock(&ec->lock);
 337         return status;
 338 }
 339
 340 static int acpi_ec_burst_enable(struct acpi_ec *ec)
 341 {
 342         u8 d;
 343         struct transaction t = {.command = ACPI_EC_BURST_ENABLE,
 344                                 .wdata = NULL, .rdata = &d,
 345                                 .wlen = 0, .rlen = 1};
 346
 347         return acpi_ec_transaction(ec, &t);
 348 }
 349
 350 static int acpi_ec_burst_disable(struct acpi_ec *ec)
 351 {
 352         struct transaction t = {.command = ACPI_EC_BURST_DISABLE,
 353                                 .wdata = NULL, .rdata = NULL,
 354                                 .wlen = 0, .rlen = 0};
 355
 356         return (acpi_ec_read_status(ec) & ACPI_EC_FLAG_BURST) ?
 357                                 acpi_ec_transaction(ec, &t) : 0;
 358 }
 359
 360 static int acpi_ec_read(struct acpi_ec *ec, u8 address, u8 * data)
 361 {
 362         int result;
 363         u8 d;
 364         struct transaction t = {.command = ACPI_EC_COMMAND_READ,
 365                                 .wdata = &address, .rdata = &d,
 366                                 .wlen = 1, .rlen = 1};
 367
 368         result = acpi_ec_transaction(ec, &t);
 369         *data = d;
 370         return result;
 371 }
 372
 373 static int acpi_ec_write(struct acpi_ec *ec, u8 address, u8 data)
 374 {
 375         u8 wdata[2] = { address, data };
 376         struct transaction t = {.command = ACPI_EC_COMMAND_WRITE,
 377                                 .wdata = wdata, .rdata = NULL,
 378                                 .wlen = 2, .rlen = 0};
 379
 380         return acpi_ec_transaction(ec, &t);
 381 }
 382
 383 /*
 384  * Externally callable EC access functions. For now, assume 1 EC only
 385  */
 386 int ec_burst_enable(void)
 387 {
 388         if (!first_ec)
 389                 return -ENODEV;
 390         return acpi_ec_burst_enable(first_ec);
 391 }
 392
 393 EXPORT_SYMBOL(ec_burst_enable);
 394
 395 int ec_burst_disable(void)
 396 {
 397         if (!first_ec)
 398                 return -ENODEV;
 399         return acpi_ec_burst_disable(first_ec);
 400 }
 401
 402 EXPORT_SYMBOL(ec_burst_disable);
 403
 404 int ec_read(u8 addr, u8 * val)
 405 {
 406         int err;
 407         u8 temp_data;
 408
 409         if (!first_ec)
 410                 return -ENODEV;
 411
 412         err = acpi_ec_read(first_ec, addr, &temp_data);
 413
 414         if (!err) {
 415                 *val = temp_data;
 416                 return 0;
 417         } else
 418                 return err;
 419 }
 420
 421 EXPORT_SYMBOL(ec_read);
 422
 423 int ec_write(u8 addr, u8 val)
 424 {
 425         int err;
 426
 427         if (!first_ec)
 428                 return -ENODEV;
 429
 430         err = acpi_ec_write(first_ec, addr, val);
 431
 432         return err;
 433 }
 434
 435 EXPORT_SYMBOL(ec_write);
 436
 437 int ec_transaction(u8 command,
 438                    const u8 * wdata, unsigned wdata_len,
 439                    u8 * rdata, unsigned rdata_len)
 440 {
 441         struct transaction t = {.command = command,
 442                                 .wdata = wdata, .rdata = rdata,
 443                                 .wlen = wdata_len, .rlen = rdata_len};
 444         if (!first_ec)
 445                 return -ENODEV;
 446
 447         return acpi_ec_transaction(first_ec, &t);
 448 }
 449
 450 EXPORT_SYMBOL(ec_transaction);
 451
 452 void acpi_ec_block_transactions(void)
 453 {
 454         struct acpi_ec *ec = first_ec;
 455
 456         if (!ec)
 457                 return;
 458
 459         mutex_lock(&ec->lock);
 460         /* Prevent transactions from being carried out */
 461         set_bit(EC_FLAGS_BLOCKED, &ec->flags);
 462         mutex_unlock(&ec->lock);
 463 }
 464
 465 void acpi_ec_unblock_transactions(void)
 466 {
 467         struct acpi_ec *ec = first_ec;
 468
 469         if (!ec)
 470                 return;
 471
 472         mutex_lock(&ec->lock);
 473         /* Allow transactions to be carried out again */
 474         clear_bit(EC_FLAGS_BLOCKED, &ec->flags);
 475         mutex_unlock(&ec->lock);
 476 }
 477
 478 void acpi_ec_unblock_transactions_early(void)
 479 {
 480         /*
 481          * Allow transactions to happen again (this function is called from
 482          * atomic context during wakeup, so we don't need to acquire the mutex).
 483          */
 484         if (first_ec)
 485                 clear_bit(EC_FLAGS_BLOCKED, &first_ec->flags);
 486 }
 487
 488 static int acpi_ec_query_unlocked(struct acpi_ec *ec, u8 * data)
 489 {
 490         int result;
 491         u8 d;
 492         struct transaction t = {.command = ACPI_EC_COMMAND_QUERY,
 493                                 .wdata = NULL, .rdata = &d,
 494                                 .wlen = 0, .rlen = 1};
 495         if (!ec || !data)
 496                 return -EINVAL;
 497         /*
 498          * Query the EC to find out which _Qxx method we need to evaluate.
 499          * Note that successful completion of the query causes the ACPI_EC_SCI
 500          * bit to be cleared (and thus clearing the interrupt source).
 501          */
 502         result = acpi_ec_transaction_unlocked(ec, &t);
 503         if (result)
 504                 return result;
 505         if (!d)
 506                 return -ENODATA;
 507         *data = d;
 508         return 0;
 509 }
 510
 511 /* --------------------------------------------------------------------------
 512                                 Event Management
 513    -------------------------------------------------------------------------- */
 514 int acpi_ec_add_query_handler(struct acpi_ec *ec, u8 query_bit,
 515                               acpi_handle handle, acpi_ec_query_func func,
 516                               void *data)
 517 {
 518         struct acpi_ec_query_handler *handler =
 519             kzalloc(sizeof(struct acpi_ec_query_handler), GFP_KERNEL);
 520         if (!handler)
 521                 return -ENOMEM;
 522
 523         handler->query_bit = query_bit;
 524         handler->handle = handle;
 525         handler->func = func;
 526         handler->data = data;
 527         mutex_lock(&ec->lock);
 528         list_add(&handler->node, &ec->list);
 529         mutex_unlock(&ec->lock);
 530         return 0;
 531 }
 532
 533 EXPORT_SYMBOL_GPL(acpi_ec_add_query_handler);
 534
 535 void acpi_ec_remove_query_handler(struct acpi_ec *ec, u8 query_bit)
 536 {
 537         struct acpi_ec_query_handler *handler, *tmp;
 538         mutex_lock(&ec->lock);
 539         list_for_each_entry_safe(handler, tmp, &ec->list, node) {
 540                 if (query_bit == handler->query_bit) {
 541                         list_del(&handler->node);
 542                         kfree(handler);
 543                 }
 544         }
 545         mutex_unlock(&ec->lock);
 546 }
 547
 548 EXPORT_SYMBOL_GPL(acpi_ec_remove_query_handler);
 549
 550 static void acpi_ec_run(void *cxt)
 551 {
 552         struct acpi_ec_query_handler *handler = cxt;
 553         if (!handler)
 554                 return;
 555         pr_debug(PREFIX "start query execution\n");
 556         if (handler->func)
 557                 handler->func(handler->data);
 558         else if (handler->handle)
 559                 acpi_evaluate_object(handler->handle, NULL, NULL, NULL);
 560         pr_debug(PREFIX "stop query execution\n");
 561         kfree(handler);
 562 }
 563
 564 static int acpi_ec_sync_query(struct acpi_ec *ec)
 565 {
 566         u8 value = 0;
 567         int status;
 568         struct acpi_ec_query_handler *handler, *copy;
 569         if ((status = acpi_ec_query_unlocked(ec, &value)))
 570                 return status;
 571         list_for_each_entry(handler, &ec->list, node) {
 572                 if (value == handler->query_bit) {
 573                         /* have custom handler for this bit */
 574                         copy = kmalloc(sizeof(*handler), GFP_KERNEL);
 575                         if (!copy)
 576                                 return -ENOMEM;
 577                         memcpy(copy, handler, sizeof(*copy));
 578                         pr_debug(PREFIX "push query execution (0x%2x) on queue\n", value);
 579                         return acpi_os_execute((copy->func) ?
 580                                 OSL_NOTIFY_HANDLER : OSL_GPE_HANDLER,
 581                                 acpi_ec_run, copy);
 582                 }
 583         }
 584         return 0;
 585 }
 586
 587 static void acpi_ec_gpe_query(void *ec_cxt)
 588 {
 589         struct acpi_ec *ec = ec_cxt;
 590         if (!ec)
 591                 return;
 592         mutex_lock(&ec->lock);
 593         acpi_ec_sync_query(ec);
 594         mutex_unlock(&ec->lock);
 595 }
 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         /* Find and register all query methods */
 812         acpi_walk_namespace(ACPI_TYPE_METHOD, ec->handle, 1,
 813                             acpi_ec_register_query_methods, NULL, ec, NULL);
 814
 815         if (!first_ec)
 816                 first_ec = ec;
 817         device->driver_data = ec;
 818
 819         WARN(!request_region(ec->data_addr, 1, "EC data"),
 820              "Could not request EC data io port 0x%lx", ec->data_addr);
 821         WARN(!request_region(ec->command_addr, 1, "EC cmd"),
 822              "Could not request EC cmd io port 0x%lx", ec->command_addr);
 823
 824         pr_info(PREFIX "GPE = 0x%lx, I/O: command/status = 0x%lx, data = 0x%lx\n",
 825                           ec->gpe, ec->command_addr, ec->data_addr);
 826
 827         ret = ec_install_handlers(ec);
 828
 829         /* EC is fully operational, allow queries */
 830         clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags);
 831         return ret;
 832 }
 833
 834 static int acpi_ec_remove(struct acpi_device *device, int type)
 835 {
 836         struct acpi_ec *ec;
 837         struct acpi_ec_query_handler *handler, *tmp;
 838
 839         if (!device)
 840                 return -EINVAL;
 841
 842         ec = acpi_driver_data(device);
 843         ec_remove_handlers(ec);
 844         mutex_lock(&ec->lock);
 845         list_for_each_entry_safe(handler, tmp, &ec->list, node) {
 846                 list_del(&handler->node);
 847                 kfree(handler);
 848         }
 849         mutex_unlock(&ec->lock);
 850         release_region(ec->data_addr, 1);
 851         release_region(ec->command_addr, 1);
 852         device->driver_data = NULL;
 853         if (ec == first_ec)
 854                 first_ec = NULL;
 855         kfree(ec);
 856         return 0;
 857 }
 858
 859 static acpi_status
 860 ec_parse_io_ports(struct acpi_resource *resource, void *context)
 861 {
 862         struct acpi_ec *ec = context;
 863
 864         if (resource->type != ACPI_RESOURCE_TYPE_IO)
 865                 return AE_OK;
 866
 867         /*
 868          * The first address region returned is the data port, and
 869          * the second address region returned is the status/command
 870          * port.
 871          */
 872         if (ec->data_addr == 0)
 873                 ec->data_addr = resource->data.io.minimum;
 874         else if (ec->command_addr == 0)
 875                 ec->command_addr = resource->data.io.minimum;
 876         else
 877                 return AE_CTRL_TERMINATE;
 878
 879         return AE_OK;
 880 }
 881
 882 int __init acpi_boot_ec_enable(void)
 883 {
 884         if (!boot_ec || test_bit(EC_FLAGS_HANDLERS_INSTALLED, &boot_ec->flags))
 885                 return 0;
 886         if (!ec_install_handlers(boot_ec)) {
 887                 first_ec = boot_ec;
 888                 return 0;
 889         }
 890         return -EFAULT;
 891 }
 892
 893 static const struct acpi_device_id ec_device_ids[] = {
 894         {"PNP0C09", 0},
 895         {"", 0},
 896 };
 897
 898 /* Some BIOS do not survive early DSDT scan, skip it */
 899 static int ec_skip_dsdt_scan(const struct dmi_system_id *id)
 900 {
 901         EC_FLAGS_SKIP_DSDT_SCAN = 1;
 902         return 0;
 903 }
 904
 905 /* ASUStek often supplies us with broken ECDT, validate it */
 906 static int ec_validate_ecdt(const struct dmi_system_id *id)
 907 {
 908         EC_FLAGS_VALIDATE_ECDT = 1;
 909         return 0;
 910 }
 911
 912 /* MSI EC needs special treatment, enable it */
 913 static int ec_flag_msi(const struct dmi_system_id *id)
 914 {
 915         printk(KERN_DEBUG PREFIX "Detected MSI hardware, enabling workarounds.\n");
 916         EC_FLAGS_MSI = 1;
 917         EC_FLAGS_VALIDATE_ECDT = 1;
 918         return 0;
 919 }
 920
 921 /*
 922  * Clevo M720 notebook actually works ok with IRQ mode, if we lifted
 923  * the GPE storm threshold back to 20
 924  */
 925 static int ec_enlarge_storm_threshold(const struct dmi_system_id *id)
 926 {
 927         pr_debug("Setting the EC GPE storm threshold to 20\n");
 928         ec_storm_threshold  = 20;
 929         return 0;
 930 }
 931
 932 static struct dmi_system_id __initdata ec_dmi_table[] = {
 933         {
 934         ec_skip_dsdt_scan, "Compal JFL92", {
 935         DMI_MATCH(DMI_BIOS_VENDOR, "COMPAL"),
 936         DMI_MATCH(DMI_BOARD_NAME, "JFL92") }, NULL},
 937         {
 938         ec_flag_msi, "MSI hardware", {
 939         DMI_MATCH(DMI_BIOS_VENDOR, "Micro-Star")}, NULL},
 940         {
 941         ec_flag_msi, "MSI hardware", {
 942         DMI_MATCH(DMI_SYS_VENDOR, "Micro-Star")}, NULL},
 943         {
 944         ec_flag_msi, "MSI hardware", {
 945         DMI_MATCH(DMI_CHASSIS_VENDOR, "MICRO-Star")}, NULL},
 946         {
 947         ec_flag_msi, "MSI hardware", {
 948         DMI_MATCH(DMI_CHASSIS_VENDOR, "MICRO-STAR")}, NULL},
 949         {
 950         ec_flag_msi, "Quanta hardware", {
 951         DMI_MATCH(DMI_SYS_VENDOR, "Quanta"),
 952         DMI_MATCH(DMI_PRODUCT_NAME, "TW8/SW8/DW8"),}, NULL},
 953         {
 954         ec_flag_msi, "Quanta hardware", {
 955         DMI_MATCH(DMI_SYS_VENDOR, "Quanta"),
 956         DMI_MATCH(DMI_PRODUCT_NAME, "TW9/SW9"),}, NULL},
 957         {
 958         ec_validate_ecdt, "ASUS hardware", {
 959         DMI_MATCH(DMI_BIOS_VENDOR, "ASUS") }, NULL},
 960         {
 961         ec_validate_ecdt, "ASUS hardware", {
 962         DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTeK Computer Inc.") }, NULL},
 963         {
 964         ec_enlarge_storm_threshold, "CLEVO hardware", {
 965         DMI_MATCH(DMI_SYS_VENDOR, "CLEVO Co."),
 966         DMI_MATCH(DMI_PRODUCT_NAME, "M720T/M730T"),}, NULL},
 967         {
 968         ec_validate_ecdt, "ASUS hardware", {
 969         DMI_MATCH(DMI_SYS_VENDOR, "ASUSTek Computer Inc."),
 970         DMI_MATCH(DMI_PRODUCT_NAME, "L4R"),}, NULL},
 971         {},
 972 };
 973
 974 int __init acpi_ec_ecdt_probe(void)
 975 {
 976         acpi_status status;
 977         struct acpi_ec *saved_ec = NULL;
 978         struct acpi_table_ecdt *ecdt_ptr;
 979
 980         boot_ec = make_acpi_ec();
 981         if (!boot_ec)
 982                 return -ENOMEM;
 983         /*
 984          * Generate a boot ec context
 985          */
 986         dmi_check_system(ec_dmi_table);
 987         status = acpi_get_table(ACPI_SIG_ECDT, 1,
 988                                 (struct acpi_table_header **)&ecdt_ptr);
 989         if (ACPI_SUCCESS(status)) {
 990                 pr_info(PREFIX "EC description table is found, configuring boot EC\n");
 991                 boot_ec->command_addr = ecdt_ptr->control.address;
 992                 boot_ec->data_addr = ecdt_ptr->data.address;
 993                 boot_ec->gpe = ecdt_ptr->gpe;
 994                 boot_ec->handle = ACPI_ROOT_OBJECT;
 995                 acpi_get_handle(ACPI_ROOT_OBJECT, ecdt_ptr->id, &boot_ec->handle);
 996                 /* Don't trust ECDT, which comes from ASUSTek */
 997                 if (!EC_FLAGS_VALIDATE_ECDT)
 998                         goto install;
 999                 saved_ec = kmemdup(boot_ec, sizeof(struct acpi_ec), GFP_KERNEL);
1000                 if (!saved_ec)
1001                         return -ENOMEM;
1002         /* fall through */
1003         }
1004
1005         if (EC_FLAGS_SKIP_DSDT_SCAN)
1006                 return -ENODEV;
1007
1008         /* This workaround is needed only on some broken machines,
1009          * which require early EC, but fail to provide ECDT */
1010         printk(KERN_DEBUG PREFIX "Look up EC in DSDT\n");
1011         status = acpi_get_devices(ec_device_ids[0].id, ec_parse_device,
1012                                         boot_ec, NULL);
1013         /* Check that acpi_get_devices actually find something */
1014         if (ACPI_FAILURE(status) || !boot_ec->handle)
1015                 goto error;
1016         if (saved_ec) {
1017                 /* try to find good ECDT from ASUSTek */
1018                 if (saved_ec->command_addr != boot_ec->command_addr ||
1019                     saved_ec->data_addr != boot_ec->data_addr ||
1020                     saved_ec->gpe != boot_ec->gpe ||
1021                     saved_ec->handle != boot_ec->handle)
1022                         pr_info(PREFIX "ASUSTek keeps feeding us with broken "
1023                         "ECDT tables, which are very hard to workaround. "
1024                         "Trying to use DSDT EC info instead. Please send "
1025                         "output of acpidump to linux-acpi@vger.kernel.org\n");
1026                 kfree(saved_ec);
1027                 saved_ec = NULL;
1028         } else {
1029                 /* We really need to limit this workaround, the only ASUS,
1030                 * which needs it, has fake EC._INI method, so use it as flag.
1031                 * Keep boot_ec struct as it will be needed soon.
1032                 */
1033                 acpi_handle dummy;
1034                 if (!dmi_name_in_vendors("ASUS") ||
1035                     ACPI_FAILURE(acpi_get_handle(boot_ec->handle, "_INI",
1036                                                         &dummy)))
1037                         return -ENODEV;
1038         }
1039 install:
1040         if (!ec_install_handlers(boot_ec)) {
1041                 first_ec = boot_ec;
1042                 return 0;
1043         }
1044 error:
1045         kfree(boot_ec);
1046         boot_ec = NULL;
1047         return -ENODEV;
1048 }
1049
1050 static struct acpi_driver acpi_ec_driver = {
1051         .name = "ec",
1052         .class = ACPI_EC_CLASS,
1053         .ids = ec_device_ids,
1054         .ops = {
1055                 .add = acpi_ec_add,
1056                 .remove = acpi_ec_remove,
1057                 },
1058 };
1059
1060 int __init acpi_ec_init(void)
1061 {
1062         int result = 0;
1063
1064         /* Now register the driver for the EC */
1065         result = acpi_bus_register_driver(&acpi_ec_driver);
1066         if (result < 0)
1067                 return -ENODEV;
1068
1069         return result;
1070 }
1071
1072 /* EC driver currently not unloadable */
1073 #if 0
1074 static void __exit acpi_ec_exit(void)
1075 {
1076
1077         acpi_bus_unregister_driver(&acpi_ec_driver);
1078         return;
1079 }
1080 #endif  /* 0 */