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 #define ACPI_EC_CLASS                   "embedded_controller"
  47 #define ACPI_EC_DEVICE_NAME             "Embedded Controller"
  48 #define ACPI_EC_FILE_INFO               "info"
  49
  50 #define PREFIX                          "ACPI: EC: "
  51
  52 /* EC status register */
  53 #define ACPI_EC_FLAG_OBF        0x01    /* Output buffer full */
  54 #define ACPI_EC_FLAG_IBF        0x02    /* Input buffer full */
  55 #define ACPI_EC_FLAG_BURST      0x10    /* burst mode */
  56 #define ACPI_EC_FLAG_SCI        0x20    /* EC-SCI occurred */
  57
  58 /* EC commands */
  59 enum ec_command {
  60         ACPI_EC_COMMAND_READ = 0x80,
  61         ACPI_EC_COMMAND_WRITE = 0x81,
  62         ACPI_EC_BURST_ENABLE = 0x82,
  63         ACPI_EC_BURST_DISABLE = 0x83,
  64         ACPI_EC_COMMAND_QUERY = 0x84,
  65 };
  66
  67 #define ACPI_EC_DELAY           500     /* Wait 500ms max. during EC ops */
  68 #define ACPI_EC_UDELAY_GLK      1000    /* Wait 1ms max. to get global lock */
  69 #define ACPI_EC_CDELAY          10      /* Wait 10us before polling EC */
  70 #define ACPI_EC_MSI_UDELAY      550     /* Wait 550us for MSI EC */
  71
  72 #define ACPI_EC_STORM_THRESHOLD 8       /* number of false interrupts
  73                                            per one transaction */
  74
  75 enum {
  76         EC_FLAGS_QUERY_PENDING,         /* Query is pending */
  77         EC_FLAGS_GPE_STORM,             /* GPE storm detected */
  78         EC_FLAGS_HANDLERS_INSTALLED,    /* Handlers for GPE and
  79                                          * OpReg are installed */
  80         EC_FLAGS_BLOCKED,               /* Transactions are blocked */
  81 };
  82
  83 /* If we find an EC via the ECDT, we need to keep a ptr to its context */
  84 /* External interfaces use first EC only, so remember */
  85 typedef int (*acpi_ec_query_func) (void *data);
  86
  87 struct acpi_ec_query_handler {
  88         struct list_head node;
  89         acpi_ec_query_func func;
  90         acpi_handle handle;
  91         void *data;
  92         u8 query_bit;
  93 };
  94
  95 struct transaction {
  96         const u8 *wdata;
  97         u8 *rdata;
  98         unsigned short irq_count;
  99         u8 command;
 100         u8 wi;
 101         u8 ri;
 102         u8 wlen;
 103         u8 rlen;
 104         bool done;
 105 };
 106
 107 static struct acpi_ec {
 108         acpi_handle handle;
 109         unsigned long gpe;
 110         unsigned long command_addr;
 111         unsigned long data_addr;
 112         unsigned long global_lock;
 113         unsigned long flags;
 114         struct mutex lock;
 115         wait_queue_head_t wait;
 116         struct list_head list;
 117         struct transaction *curr;
 118         spinlock_t curr_lock;
 119 } *boot_ec, *first_ec;
 120
 121 static int EC_FLAGS_MSI; /* Out-of-spec MSI controller */
 122 static int EC_FLAGS_VALIDATE_ECDT; /* ASUStec ECDTs need to be validated */
 123 static int EC_FLAGS_SKIP_DSDT_SCAN; /* Not all BIOS survive early DSDT scan */
 124
 125 /* --------------------------------------------------------------------------
 126                              Transaction Management
 127    -------------------------------------------------------------------------- */
 128
 129 static inline u8 acpi_ec_read_status(struct acpi_ec *ec)
 130 {
 131         u8 x = inb(ec->command_addr);
 132         pr_debug(PREFIX "---> status = 0x%2.2x\n", x);
 133         return x;
 134 }
 135
 136 static inline u8 acpi_ec_read_data(struct acpi_ec *ec)
 137 {
 138         u8 x = inb(ec->data_addr);
 139         pr_debug(PREFIX "---> data = 0x%2.2x\n", x);
 140         return x;
 141 }
 142
 143 static inline void acpi_ec_write_cmd(struct acpi_ec *ec, u8 command)
 144 {
 145         pr_debug(PREFIX "<--- command = 0x%2.2x\n", command);
 146         outb(command, ec->command_addr);
 147 }
 148
 149 static inline void acpi_ec_write_data(struct acpi_ec *ec, u8 data)
 150 {
 151         pr_debug(PREFIX "<--- data = 0x%2.2x\n", data);
 152         outb(data, ec->data_addr);
 153 }
 154
 155 static int ec_transaction_done(struct acpi_ec *ec)
 156 {
 157         unsigned long flags;
 158         int ret = 0;
 159         spin_lock_irqsave(&ec->curr_lock, flags);
 160         if (!ec->curr || ec->curr->done)
 161                 ret = 1;
 162         spin_unlock_irqrestore(&ec->curr_lock, flags);
 163         return ret;
 164 }
 165
 166 static void start_transaction(struct acpi_ec *ec)
 167 {
 168         ec->curr->irq_count = ec->curr->wi = ec->curr->ri = 0;
 169         ec->curr->done = false;
 170         acpi_ec_write_cmd(ec, ec->curr->command);
 171 }
 172
 173 static void advance_transaction(struct acpi_ec *ec, u8 status)
 174 {
 175         unsigned long flags;
 176         spin_lock_irqsave(&ec->curr_lock, flags);
 177         if (!ec->curr)
 178                 goto unlock;
 179         if (ec->curr->wlen > ec->curr->wi) {
 180                 if ((status & ACPI_EC_FLAG_IBF) == 0)
 181                         acpi_ec_write_data(ec,
 182                                 ec->curr->wdata[ec->curr->wi++]);
 183                 else
 184                         goto err;
 185         } else if (ec->curr->rlen > ec->curr->ri) {
 186                 if ((status & ACPI_EC_FLAG_OBF) == 1) {
 187                         ec->curr->rdata[ec->curr->ri++] = acpi_ec_read_data(ec);
 188                         if (ec->curr->rlen == ec->curr->ri)
 189                                 ec->curr->done = true;
 190                 } else
 191                         goto err;
 192         } else if (ec->curr->wlen == ec->curr->wi &&
 193                    (status & ACPI_EC_FLAG_IBF) == 0)
 194                 ec->curr->done = true;
 195         goto unlock;
 196 err:
 197         /* false interrupt, state didn't change */
 198         if (in_interrupt())
 199                 ++ec->curr->irq_count;
 200 unlock:
 201         spin_unlock_irqrestore(&ec->curr_lock, flags);
 202 }
 203
 204 static int acpi_ec_sync_query(struct acpi_ec *ec);
 205
 206 static int ec_check_sci_sync(struct acpi_ec *ec, u8 state)
 207 {
 208         if (state & ACPI_EC_FLAG_SCI) {
 209                 if (!test_and_set_bit(EC_FLAGS_QUERY_PENDING, &ec->flags))
 210                         return acpi_ec_sync_query(ec);
 211         }
 212         return 0;
 213 }
 214
 215 static int ec_poll(struct acpi_ec *ec)
 216 {
 217         unsigned long flags;
 218         int repeat = 2; /* number of command restarts */
 219         while (repeat--) {
 220                 unsigned long delay = jiffies +
 221                         msecs_to_jiffies(ACPI_EC_DELAY);
 222                 do {
 223                         /* don't sleep with disabled interrupts */
 224                         if (EC_FLAGS_MSI || irqs_disabled()) {
 225                                 udelay(ACPI_EC_MSI_UDELAY);
 226                                 if (ec_transaction_done(ec))
 227                                         return 0;
 228                         } else {
 229                                 if (wait_event_timeout(ec->wait,
 230                                                 ec_transaction_done(ec),
 231                                                 msecs_to_jiffies(1)))
 232                                         return 0;
 233                         }
 234                         advance_transaction(ec, acpi_ec_read_status(ec));
 235                 } while (time_before(jiffies, delay));
 236                 if (acpi_ec_read_status(ec) & ACPI_EC_FLAG_IBF)
 237                         break;
 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(ACPI_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                 /*
 315                  * It has to be disabled at the hardware level regardless of the
 316                  * GPE reference counting, so that it doesn't trigger.
 317                  */
 318                 acpi_set_gpe(NULL, ec->gpe, ACPI_GPE_DISABLE);
 319         }
 320
 321         status = acpi_ec_transaction_unlocked(ec, t);
 322
 323         /* check if we received SCI during transaction */
 324         ec_check_sci_sync(ec, acpi_ec_read_status(ec));
 325         if (test_bit(EC_FLAGS_GPE_STORM, &ec->flags)) {
 326                 msleep(1);
 327                 /*
 328                  * It is safe to enable the GPE outside of the transaction.  Use
 329                  * acpi_set_gpe() for that, since we used it to disable the GPE
 330                  * above.
 331                  */
 332                 acpi_set_gpe(NULL, ec->gpe, ACPI_GPE_ENABLE);
 333         } else if (t->irq_count > ACPI_EC_STORM_THRESHOLD) {
 334                 pr_info(PREFIX "GPE storm detected, "
 335                         "transactions will use polling mode\n");
 336                 set_bit(EC_FLAGS_GPE_STORM, &ec->flags);
 337         }
 338         pr_debug(PREFIX "transaction end\n");
 339 end:
 340         if (ec->global_lock)
 341                 acpi_release_global_lock(glk);
 342 unlock:
 343         mutex_unlock(&ec->lock);
 344         return status;
 345 }
 346
 347 static int acpi_ec_burst_enable(struct acpi_ec *ec)
 348 {
 349         u8 d;
 350         struct transaction t = {.command = ACPI_EC_BURST_ENABLE,
 351                                 .wdata = NULL, .rdata = &d,
 352                                 .wlen = 0, .rlen = 1};
 353
 354         return acpi_ec_transaction(ec, &t);
 355 }
 356
 357 static int acpi_ec_burst_disable(struct acpi_ec *ec)
 358 {
 359         struct transaction t = {.command = ACPI_EC_BURST_DISABLE,
 360                                 .wdata = NULL, .rdata = NULL,
 361                                 .wlen = 0, .rlen = 0};
 362
 363         return (acpi_ec_read_status(ec) & ACPI_EC_FLAG_BURST) ?
 364                                 acpi_ec_transaction(ec, &t) : 0;
 365 }
 366
 367 static int acpi_ec_read(struct acpi_ec *ec, u8 address, u8 * data)
 368 {
 369         int result;
 370         u8 d;
 371         struct transaction t = {.command = ACPI_EC_COMMAND_READ,
 372                                 .wdata = &address, .rdata = &d,
 373                                 .wlen = 1, .rlen = 1};
 374
 375         result = acpi_ec_transaction(ec, &t);
 376         *data = d;
 377         return result;
 378 }
 379
 380 static int acpi_ec_write(struct acpi_ec *ec, u8 address, u8 data)
 381 {
 382         u8 wdata[2] = { address, data };
 383         struct transaction t = {.command = ACPI_EC_COMMAND_WRITE,
 384                                 .wdata = wdata, .rdata = NULL,
 385                                 .wlen = 2, .rlen = 0};
 386
 387         return acpi_ec_transaction(ec, &t);
 388 }
 389
 390 /*
 391  * Externally callable EC access functions. For now, assume 1 EC only
 392  */
 393 int ec_burst_enable(void)
 394 {
 395         if (!first_ec)
 396                 return -ENODEV;
 397         return acpi_ec_burst_enable(first_ec);
 398 }
 399
 400 EXPORT_SYMBOL(ec_burst_enable);
 401
 402 int ec_burst_disable(void)
 403 {
 404         if (!first_ec)
 405                 return -ENODEV;
 406         return acpi_ec_burst_disable(first_ec);
 407 }
 408
 409 EXPORT_SYMBOL(ec_burst_disable);
 410
 411 int ec_read(u8 addr, u8 * val)
 412 {
 413         int err;
 414         u8 temp_data;
 415
 416         if (!first_ec)
 417                 return -ENODEV;
 418
 419         err = acpi_ec_read(first_ec, addr, &temp_data);
 420
 421         if (!err) {
 422                 *val = temp_data;
 423                 return 0;
 424         } else
 425                 return err;
 426 }
 427
 428 EXPORT_SYMBOL(ec_read);
 429
 430 int ec_write(u8 addr, u8 val)
 431 {
 432         int err;
 433
 434         if (!first_ec)
 435                 return -ENODEV;
 436
 437         err = acpi_ec_write(first_ec, addr, val);
 438
 439         return err;
 440 }
 441
 442 EXPORT_SYMBOL(ec_write);
 443
 444 int ec_transaction(u8 command,
 445                    const u8 * wdata, unsigned wdata_len,
 446                    u8 * rdata, unsigned rdata_len,
 447                    int force_poll)
 448 {
 449         struct transaction t = {.command = command,
 450                                 .wdata = wdata, .rdata = rdata,
 451                                 .wlen = wdata_len, .rlen = rdata_len};
 452         if (!first_ec)
 453                 return -ENODEV;
 454
 455         return acpi_ec_transaction(first_ec, &t);
 456 }
 457
 458 EXPORT_SYMBOL(ec_transaction);
 459
 460 void acpi_ec_block_transactions(void)
 461 {
 462         struct acpi_ec *ec = first_ec;
 463
 464         if (!ec)
 465                 return;
 466
 467         mutex_lock(&ec->lock);
 468         /* Prevent transactions from being carried out */
 469         set_bit(EC_FLAGS_BLOCKED, &ec->flags);
 470         mutex_unlock(&ec->lock);
 471 }
 472
 473 void acpi_ec_unblock_transactions(void)
 474 {
 475         struct acpi_ec *ec = first_ec;
 476
 477         if (!ec)
 478                 return;
 479
 480         mutex_lock(&ec->lock);
 481         /* Allow transactions to be carried out again */
 482         clear_bit(EC_FLAGS_BLOCKED, &ec->flags);
 483         mutex_unlock(&ec->lock);
 484 }
 485
 486 void acpi_ec_unblock_transactions_early(void)
 487 {
 488         /*
 489          * Allow transactions to happen again (this function is called from
 490          * atomic context during wakeup, so we don't need to acquire the mutex).
 491          */
 492         if (first_ec)
 493                 clear_bit(EC_FLAGS_BLOCKED, &first_ec->flags);
 494 }
 495
 496 static int acpi_ec_query_unlocked(struct acpi_ec *ec, u8 * data)
 497 {
 498         int result;
 499         u8 d;
 500         struct transaction t = {.command = ACPI_EC_COMMAND_QUERY,
 501                                 .wdata = NULL, .rdata = &d,
 502                                 .wlen = 0, .rlen = 1};
 503         if (!ec || !data)
 504                 return -EINVAL;
 505         /*
 506          * Query the EC to find out which _Qxx method we need to evaluate.
 507          * Note that successful completion of the query causes the ACPI_EC_SCI
 508          * bit to be cleared (and thus clearing the interrupt source).
 509          */
 510         result = acpi_ec_transaction_unlocked(ec, &t);
 511         if (result)
 512                 return result;
 513         if (!d)
 514                 return -ENODATA;
 515         *data = d;
 516         return 0;
 517 }
 518
 519 /* --------------------------------------------------------------------------
 520                                 Event Management
 521    -------------------------------------------------------------------------- */
 522 int acpi_ec_add_query_handler(struct acpi_ec *ec, u8 query_bit,
 523                               acpi_handle handle, acpi_ec_query_func func,
 524                               void *data)
 525 {
 526         struct acpi_ec_query_handler *handler =
 527             kzalloc(sizeof(struct acpi_ec_query_handler), GFP_KERNEL);
 528         if (!handler)
 529                 return -ENOMEM;
 530
 531         handler->query_bit = query_bit;
 532         handler->handle = handle;
 533         handler->func = func;
 534         handler->data = data;
 535         mutex_lock(&ec->lock);
 536         list_add(&handler->node, &ec->list);
 537         mutex_unlock(&ec->lock);
 538         return 0;
 539 }
 540
 541 EXPORT_SYMBOL_GPL(acpi_ec_add_query_handler);
 542
 543 void acpi_ec_remove_query_handler(struct acpi_ec *ec, u8 query_bit)
 544 {
 545         struct acpi_ec_query_handler *handler, *tmp;
 546         mutex_lock(&ec->lock);
 547         list_for_each_entry_safe(handler, tmp, &ec->list, node) {
 548                 if (query_bit == handler->query_bit) {
 549                         list_del(&handler->node);
 550                         kfree(handler);
 551                 }
 552         }
 553         mutex_unlock(&ec->lock);
 554 }
 555
 556 EXPORT_SYMBOL_GPL(acpi_ec_remove_query_handler);
 557
 558 static void acpi_ec_run(void *cxt)
 559 {
 560         struct acpi_ec_query_handler *handler = cxt;
 561         if (!handler)
 562                 return;
 563         pr_debug(PREFIX "start query execution\n");
 564         if (handler->func)
 565                 handler->func(handler->data);
 566         else if (handler->handle)
 567                 acpi_evaluate_object(handler->handle, NULL, NULL, NULL);
 568         pr_debug(PREFIX "stop query execution\n");
 569         kfree(handler);
 570 }
 571
 572 static int acpi_ec_sync_query(struct acpi_ec *ec)
 573 {
 574         u8 value = 0;
 575         int status;
 576         struct acpi_ec_query_handler *handler, *copy;
 577         if ((status = acpi_ec_query_unlocked(ec, &value)))
 578                 return status;
 579         list_for_each_entry(handler, &ec->list, node) {
 580                 if (value == handler->query_bit) {
 581                         /* have custom handler for this bit */
 582                         copy = kmalloc(sizeof(*handler), GFP_KERNEL);
 583                         if (!copy)
 584                                 return -ENOMEM;
 585                         memcpy(copy, handler, sizeof(*copy));
 586                         pr_debug(PREFIX "push query execution (0x%2x) on queue\n", value);
 587                         return acpi_os_execute((copy->func) ?
 588                                 OSL_NOTIFY_HANDLER : OSL_GPE_HANDLER,
 589                                 acpi_ec_run, copy);
 590                 }
 591         }
 592         return 0;
 593 }
 594
 595 static void acpi_ec_gpe_query(void *ec_cxt)
 596 {
 597         struct acpi_ec *ec = ec_cxt;
 598         if (!ec)
 599                 return;
 600         mutex_lock(&ec->lock);
 601         acpi_ec_sync_query(ec);
 602         mutex_unlock(&ec->lock);
 603 }
 604
 605 static void acpi_ec_gpe_query(void *ec_cxt);
 606
 607 static int ec_check_sci(struct acpi_ec *ec, u8 state)
 608 {
 609         if (state & ACPI_EC_FLAG_SCI) {
 610                 if (!test_and_set_bit(EC_FLAGS_QUERY_PENDING, &ec->flags)) {
 611                         pr_debug(PREFIX "push gpe query to the queue\n");
 612                         return acpi_os_execute(OSL_NOTIFY_HANDLER,
 613                                 acpi_ec_gpe_query, ec);
 614                 }
 615         }
 616         return 0;
 617 }
 618
 619 static u32 acpi_ec_gpe_handler(void *data)
 620 {
 621         struct acpi_ec *ec = data;
 622
 623         pr_debug(PREFIX "~~~> interrupt\n");
 624
 625         advance_transaction(ec, acpi_ec_read_status(ec));
 626         if (ec_transaction_done(ec) &&
 627             (acpi_ec_read_status(ec) & ACPI_EC_FLAG_IBF) == 0) {
 628                 wake_up(&ec->wait);
 629                 ec_check_sci(ec, acpi_ec_read_status(ec));
 630         }
 631         return ACPI_INTERRUPT_HANDLED;
 632 }
 633
 634 /* --------------------------------------------------------------------------
 635                              Address Space Management
 636    -------------------------------------------------------------------------- */
 637
 638 static acpi_status
 639 acpi_ec_space_handler(u32 function, acpi_physical_address address,
 640                       u32 bits, u64 *value64,
 641                       void *handler_context, void *region_context)
 642 {
 643         struct acpi_ec *ec = handler_context;
 644         int result = 0, i, bytes = bits / 8;
 645         u8 *value = (u8 *)value64;
 646
 647         if ((address > 0xFF) || !value || !handler_context)
 648                 return AE_BAD_PARAMETER;
 649
 650         if (function != ACPI_READ && function != ACPI_WRITE)
 651                 return AE_BAD_PARAMETER;
 652
 653         if (EC_FLAGS_MSI || bits > 8)
 654                 acpi_ec_burst_enable(ec);
 655
 656         for (i = 0; i < bytes; ++i, ++address, ++value)
 657                 result = (function == ACPI_READ) ?
 658                         acpi_ec_read(ec, address, value) :
 659                         acpi_ec_write(ec, address, *value);
 660
 661         if (EC_FLAGS_MSI || bits > 8)
 662                 acpi_ec_burst_disable(ec);
 663
 664         switch (result) {
 665         case -EINVAL:
 666                 return AE_BAD_PARAMETER;
 667                 break;
 668         case -ENODEV:
 669                 return AE_NOT_FOUND;
 670                 break;
 671         case -ETIME:
 672                 return AE_TIME;
 673                 break;
 674         default:
 675                 return AE_OK;
 676         }
 677 }
 678
 679 /* --------------------------------------------------------------------------
 680                                Driver Interface
 681    -------------------------------------------------------------------------- */
 682 static acpi_status
 683 ec_parse_io_ports(struct acpi_resource *resource, void *context);
 684
 685 static struct acpi_ec *make_acpi_ec(void)
 686 {
 687         struct acpi_ec *ec = kzalloc(sizeof(struct acpi_ec), GFP_KERNEL);
 688         if (!ec)
 689                 return NULL;
 690         ec->flags = 1 << EC_FLAGS_QUERY_PENDING;
 691         mutex_init(&ec->lock);
 692         init_waitqueue_head(&ec->wait);
 693         INIT_LIST_HEAD(&ec->list);
 694         spin_lock_init(&ec->curr_lock);
 695         return ec;
 696 }
 697
 698 static acpi_status
 699 acpi_ec_register_query_methods(acpi_handle handle, u32 level,
 700                                void *context, void **return_value)
 701 {
 702         char node_name[5];
 703         struct acpi_buffer buffer = { sizeof(node_name), node_name };
 704         struct acpi_ec *ec = context;
 705         int value = 0;
 706         acpi_status status;
 707
 708         status = acpi_get_name(handle, ACPI_SINGLE_NAME, &buffer);
 709
 710         if (ACPI_SUCCESS(status) && sscanf(node_name, "_Q%x", &value) == 1) {
 711                 acpi_ec_add_query_handler(ec, value, handle, NULL, NULL);
 712         }
 713         return AE_OK;
 714 }
 715
 716 static acpi_status
 717 ec_parse_device(acpi_handle handle, u32 Level, void *context, void **retval)
 718 {
 719         acpi_status status;
 720         unsigned long long tmp = 0;
 721
 722         struct acpi_ec *ec = context;
 723
 724         /* clear addr values, ec_parse_io_ports depend on it */
 725         ec->command_addr = ec->data_addr = 0;
 726
 727         status = acpi_walk_resources(handle, METHOD_NAME__CRS,
 728                                      ec_parse_io_ports, ec);
 729         if (ACPI_FAILURE(status))
 730                 return status;
 731
 732         /* Get GPE bit assignment (EC events). */
 733         /* TODO: Add support for _GPE returning a package */
 734         status = acpi_evaluate_integer(handle, "_GPE", NULL, &tmp);
 735         if (ACPI_FAILURE(status))
 736                 return status;
 737         ec->gpe = tmp;
 738         /* Use the global lock for all EC transactions? */
 739         tmp = 0;
 740         acpi_evaluate_integer(handle, "_GLK", NULL, &tmp);
 741         ec->global_lock = tmp;
 742         ec->handle = handle;
 743         return AE_CTRL_TERMINATE;
 744 }
 745
 746 static int ec_install_handlers(struct acpi_ec *ec)
 747 {
 748         acpi_status status;
 749         if (test_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags))
 750                 return 0;
 751         status = acpi_install_gpe_handler(NULL, ec->gpe,
 752                                   ACPI_GPE_EDGE_TRIGGERED,
 753                                   &acpi_ec_gpe_handler, ec);
 754         if (ACPI_FAILURE(status))
 755                 return -ENODEV;
 756
 757         acpi_enable_gpe(NULL, ec->gpe, ACPI_GPE_TYPE_RUNTIME);
 758         status = acpi_install_address_space_handler(ec->handle,
 759                                                     ACPI_ADR_SPACE_EC,
 760                                                     &acpi_ec_space_handler,
 761                                                     NULL, ec);
 762         if (ACPI_FAILURE(status)) {
 763                 if (status == AE_NOT_FOUND) {
 764                         /*
 765                          * Maybe OS fails in evaluating the _REG object.
 766                          * The AE_NOT_FOUND error will be ignored and OS
 767                          * continue to initialize EC.
 768                          */
 769                         printk(KERN_ERR "Fail in evaluating the _REG object"
 770                                 " of EC device. Broken bios is suspected.\n");
 771                 } else {
 772                         acpi_remove_gpe_handler(NULL, ec->gpe,
 773                                 &acpi_ec_gpe_handler);
 774                         acpi_disable_gpe(NULL, ec->gpe, ACPI_GPE_TYPE_RUNTIME);
 775                         return -ENODEV;
 776                 }
 777         }
 778
 779         set_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags);
 780         return 0;
 781 }
 782
 783 static void ec_remove_handlers(struct acpi_ec *ec)
 784 {
 785         acpi_disable_gpe(NULL, ec->gpe, ACPI_GPE_TYPE_RUNTIME);
 786         if (ACPI_FAILURE(acpi_remove_address_space_handler(ec->handle,
 787                                 ACPI_ADR_SPACE_EC, &acpi_ec_space_handler)))
 788                 pr_err(PREFIX "failed to remove space handler\n");
 789         if (ACPI_FAILURE(acpi_remove_gpe_handler(NULL, ec->gpe,
 790                                 &acpi_ec_gpe_handler)))
 791                 pr_err(PREFIX "failed to remove gpe handler\n");
 792         clear_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags);
 793 }
 794
 795 static int acpi_ec_add(struct acpi_device *device)
 796 {
 797         struct acpi_ec *ec = NULL;
 798         int ret;
 799
 800         strcpy(acpi_device_name(device), ACPI_EC_DEVICE_NAME);
 801         strcpy(acpi_device_class(device), ACPI_EC_CLASS);
 802
 803         /* Check for boot EC */
 804         if (boot_ec &&
 805             (boot_ec->handle == device->handle ||
 806              boot_ec->handle == ACPI_ROOT_OBJECT)) {
 807                 ec = boot_ec;
 808                 boot_ec = NULL;
 809         } else {
 810                 ec = make_acpi_ec();
 811                 if (!ec)
 812                         return -ENOMEM;
 813         }
 814         if (ec_parse_device(device->handle, 0, ec, NULL) !=
 815                 AE_CTRL_TERMINATE) {
 816                         kfree(ec);
 817                         return -EINVAL;
 818         }
 819
 820         ec->handle = device->handle;
 821
 822         /* Find and register all query methods */
 823         acpi_walk_namespace(ACPI_TYPE_METHOD, ec->handle, 1,
 824                             acpi_ec_register_query_methods, NULL, ec, NULL);
 825
 826         if (!first_ec)
 827                 first_ec = ec;
 828         device->driver_data = ec;
 829         pr_info(PREFIX "GPE = 0x%lx, I/O: command/status = 0x%lx, data = 0x%lx\n",
 830                           ec->gpe, ec->command_addr, ec->data_addr);
 831
 832         ret = ec_install_handlers(ec);
 833
 834         /* EC is fully operational, allow queries */
 835         clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags);
 836         return ret;
 837 }
 838
 839 static int acpi_ec_remove(struct acpi_device *device, int type)
 840 {
 841         struct acpi_ec *ec;
 842         struct acpi_ec_query_handler *handler, *tmp;
 843
 844         if (!device)
 845                 return -EINVAL;
 846
 847         ec = acpi_driver_data(device);
 848         ec_remove_handlers(ec);
 849         mutex_lock(&ec->lock);
 850         list_for_each_entry_safe(handler, tmp, &ec->list, node) {
 851                 list_del(&handler->node);
 852                 kfree(handler);
 853         }
 854         mutex_unlock(&ec->lock);
 855         device->driver_data = NULL;
 856         if (ec == first_ec)
 857                 first_ec = NULL;
 858         kfree(ec);
 859         return 0;
 860 }
 861
 862 static acpi_status
 863 ec_parse_io_ports(struct acpi_resource *resource, void *context)
 864 {
 865         struct acpi_ec *ec = context;
 866
 867         if (resource->type != ACPI_RESOURCE_TYPE_IO)
 868                 return AE_OK;
 869
 870         /*
 871          * The first address region returned is the data port, and
 872          * the second address region returned is the status/command
 873          * port.
 874          */
 875         if (ec->data_addr == 0)
 876                 ec->data_addr = resource->data.io.minimum;
 877         else if (ec->command_addr == 0)
 878                 ec->command_addr = resource->data.io.minimum;
 879         else
 880                 return AE_CTRL_TERMINATE;
 881
 882         return AE_OK;
 883 }
 884
 885 int __init acpi_boot_ec_enable(void)
 886 {
 887         if (!boot_ec || test_bit(EC_FLAGS_HANDLERS_INSTALLED, &boot_ec->flags))
 888                 return 0;
 889         if (!ec_install_handlers(boot_ec)) {
 890                 first_ec = boot_ec;
 891                 return 0;
 892         }
 893         return -EFAULT;
 894 }
 895
 896 static const struct acpi_device_id ec_device_ids[] = {
 897         {"PNP0C09", 0},
 898         {"", 0},
 899 };
 900
 901 /* Some BIOS do not survive early DSDT scan, skip it */
 902 static int ec_skip_dsdt_scan(const struct dmi_system_id *id)
 903 {
 904         EC_FLAGS_SKIP_DSDT_SCAN = 1;
 905         return 0;
 906 }
 907
 908 /* ASUStek often supplies us with broken ECDT, validate it */
 909 static int ec_validate_ecdt(const struct dmi_system_id *id)
 910 {
 911         EC_FLAGS_VALIDATE_ECDT = 1;
 912         return 0;
 913 }
 914
 915 /* MSI EC needs special treatment, enable it */
 916 static int ec_flag_msi(const struct dmi_system_id *id)
 917 {
 918         printk(KERN_DEBUG PREFIX "Detected MSI hardware, enabling workarounds.\n");
 919         EC_FLAGS_MSI = 1;
 920         EC_FLAGS_VALIDATE_ECDT = 1;
 921         return 0;
 922 }
 923
 924 static struct dmi_system_id __initdata ec_dmi_table[] = {
 925         {
 926         ec_skip_dsdt_scan, "Compal JFL92", {
 927         DMI_MATCH(DMI_BIOS_VENDOR, "COMPAL"),
 928         DMI_MATCH(DMI_BOARD_NAME, "JFL92") }, NULL},
 929         {
 930         ec_flag_msi, "MSI hardware", {
 931         DMI_MATCH(DMI_BIOS_VENDOR, "Micro-Star")}, NULL},
 932         {
 933         ec_flag_msi, "MSI hardware", {
 934         DMI_MATCH(DMI_SYS_VENDOR, "Micro-Star")}, NULL},
 935         {
 936         ec_flag_msi, "MSI hardware", {
 937         DMI_MATCH(DMI_CHASSIS_VENDOR, "MICRO-Star")}, NULL},
 938         {
 939         ec_validate_ecdt, "ASUS hardware", {
 940         DMI_MATCH(DMI_BIOS_VENDOR, "ASUS") }, NULL},
 941         {},
 942 };
 943
 944
 945 int __init acpi_ec_ecdt_probe(void)
 946 {
 947         acpi_status status;
 948         struct acpi_ec *saved_ec = NULL;
 949         struct acpi_table_ecdt *ecdt_ptr;
 950
 951         boot_ec = make_acpi_ec();
 952         if (!boot_ec)
 953                 return -ENOMEM;
 954         /*
 955          * Generate a boot ec context
 956          */
 957         dmi_check_system(ec_dmi_table);
 958         status = acpi_get_table(ACPI_SIG_ECDT, 1,
 959                                 (struct acpi_table_header **)&ecdt_ptr);
 960         if (ACPI_SUCCESS(status)) {
 961                 pr_info(PREFIX "EC description table is found, configuring boot EC\n");
 962                 boot_ec->command_addr = ecdt_ptr->control.address;
 963                 boot_ec->data_addr = ecdt_ptr->data.address;
 964                 boot_ec->gpe = ecdt_ptr->gpe;
 965                 boot_ec->handle = ACPI_ROOT_OBJECT;
 966                 acpi_get_handle(ACPI_ROOT_OBJECT, ecdt_ptr->id, &boot_ec->handle);
 967                 /* Don't trust ECDT, which comes from ASUSTek */
 968                 if (!EC_FLAGS_VALIDATE_ECDT)
 969                         goto install;
 970                 saved_ec = kmemdup(boot_ec, sizeof(struct acpi_ec), GFP_KERNEL);
 971                 if (!saved_ec)
 972                         return -ENOMEM;
 973         /* fall through */
 974         }
 975
 976         if (EC_FLAGS_SKIP_DSDT_SCAN)
 977                 return -ENODEV;
 978
 979         /* This workaround is needed only on some broken machines,
 980          * which require early EC, but fail to provide ECDT */
 981         printk(KERN_DEBUG PREFIX "Look up EC in DSDT\n");
 982         status = acpi_get_devices(ec_device_ids[0].id, ec_parse_device,
 983                                         boot_ec, NULL);
 984         /* Check that acpi_get_devices actually find something */
 985         if (ACPI_FAILURE(status) || !boot_ec->handle)
 986                 goto error;
 987         if (saved_ec) {
 988                 /* try to find good ECDT from ASUSTek */
 989                 if (saved_ec->command_addr != boot_ec->command_addr ||
 990                     saved_ec->data_addr != boot_ec->data_addr ||
 991                     saved_ec->gpe != boot_ec->gpe ||
 992                     saved_ec->handle != boot_ec->handle)
 993                         pr_info(PREFIX "ASUSTek keeps feeding us with broken "
 994                         "ECDT tables, which are very hard to workaround. "
 995                         "Trying to use DSDT EC info instead. Please send "
 996                         "output of acpidump to linux-acpi@vger.kernel.org\n");
 997                 kfree(saved_ec);
 998                 saved_ec = NULL;
 999         } else {
1000                 /* We really need to limit this workaround, the only ASUS,
1001                 * which needs it, has fake EC._INI method, so use it as flag.
1002                 * Keep boot_ec struct as it will be needed soon.
1003                 */
1004                 acpi_handle dummy;
1005                 if (!dmi_name_in_vendors("ASUS") ||
1006                     ACPI_FAILURE(acpi_get_handle(boot_ec->handle, "_INI",
1007                                                         &dummy)))
1008                         return -ENODEV;
1009         }
1010 install:
1011         if (!ec_install_handlers(boot_ec)) {
1012                 first_ec = boot_ec;
1013                 return 0;
1014         }
1015 error:
1016         kfree(boot_ec);
1017         boot_ec = NULL;
1018         return -ENODEV;
1019 }
1020
1021 static int acpi_ec_suspend(struct acpi_device *device, pm_message_t state)
1022 {
1023         struct acpi_ec *ec = acpi_driver_data(device);
1024         /* Stop using the GPE, but keep it reference counted. */
1025         acpi_set_gpe(NULL, ec->gpe, ACPI_GPE_DISABLE);
1026         return 0;
1027 }
1028
1029 static int acpi_ec_resume(struct acpi_device *device)
1030 {
1031         struct acpi_ec *ec = acpi_driver_data(device);
1032         /* Enable the GPE again, but don't reference count it once more. */
1033         acpi_set_gpe(NULL, ec->gpe, ACPI_GPE_ENABLE);
1034         return 0;
1035 }
1036
1037 static struct acpi_driver acpi_ec_driver = {
1038         .name = "ec",
1039         .class = ACPI_EC_CLASS,
1040         .ids = ec_device_ids,
1041         .ops = {
1042                 .add = acpi_ec_add,
1043                 .remove = acpi_ec_remove,
1044                 .suspend = acpi_ec_suspend,
1045                 .resume = acpi_ec_resume,
1046                 },
1047 };
1048
1049 int __init acpi_ec_init(void)
1050 {
1051         int result = 0;
1052
1053         /* Now register the driver for the EC */
1054         result = acpi_bus_register_driver(&acpi_ec_driver);
1055         if (result < 0)
1056                 return -ENODEV;
1057
1058         return result;
1059 }
1060
1061 /* EC driver currently not unloadable */
1062 #if 0
1063 static void __exit acpi_ec_exit(void)
1064 {
1065
1066         acpi_bus_unregister_driver(&acpi_ec_driver);
1067         return;
1068 }
1069 #endif  /* 0 */