drivers/acpi/ec.c

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