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 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 void acpi_ec_gpe_query(void *ec_cxt);
 205
 206 static int ec_check_sci(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_os_execute(OSL_EC_BURST_HANDLER,
 211                                 acpi_ec_gpe_query, ec);
 212         }
 213         return 0;
 214 }
 215
 216 static int ec_poll(struct acpi_ec *ec)
 217 {
 218         unsigned long flags;
 219         int repeat = 2; /* number of command restarts */
 220         while (repeat--) {
 221                 unsigned long delay = jiffies +
 222                         msecs_to_jiffies(ACPI_EC_DELAY);
 223                 do {
 224                         /* don't sleep with disabled interrupts */
 225                         if (EC_FLAGS_MSI || irqs_disabled()) {
 226                                 udelay(ACPI_EC_MSI_UDELAY);
 227                                 if (ec_transaction_done(ec))
 228                                         return 0;
 229                         } else {
 230                                 if (wait_event_timeout(ec->wait,
 231                                                 ec_transaction_done(ec),
 232                                                 msecs_to_jiffies(1)))
 233                                         return 0;
 234                         }
 235                         advance_transaction(ec, acpi_ec_read_status(ec));
 236                 } while (time_before(jiffies, delay));
 237                 if (acpi_ec_read_status(ec) & ACPI_EC_FLAG_IBF)
 238                         break;
 239                 pr_debug(PREFIX "controller reset, restart transaction\n");
 240                 spin_lock_irqsave(&ec->curr_lock, flags);
 241                 start_transaction(ec);
 242                 spin_unlock_irqrestore(&ec->curr_lock, flags);
 243         }
 244         return -ETIME;
 245 }
 246
 247 static int acpi_ec_transaction_unlocked(struct acpi_ec *ec,
 248                                         struct transaction *t)
 249 {
 250         unsigned long tmp;
 251         int ret = 0;
 252         pr_debug(PREFIX "transaction start\n");
 253         /* disable GPE during transaction if storm is detected */
 254         if (test_bit(EC_FLAGS_GPE_STORM, &ec->flags)) {
 255                 acpi_disable_gpe(NULL, ec->gpe);
 256         }
 257         if (EC_FLAGS_MSI)
 258                 udelay(ACPI_EC_MSI_UDELAY);
 259         /* start transaction */
 260         spin_lock_irqsave(&ec->curr_lock, tmp);
 261         /* following two actions should be kept atomic */
 262         ec->curr = t;
 263         start_transaction(ec);
 264         if (ec->curr->command == ACPI_EC_COMMAND_QUERY)
 265                 clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags);
 266         spin_unlock_irqrestore(&ec->curr_lock, tmp);
 267         ret = ec_poll(ec);
 268         pr_debug(PREFIX "transaction end\n");
 269         spin_lock_irqsave(&ec->curr_lock, tmp);
 270         ec->curr = NULL;
 271         spin_unlock_irqrestore(&ec->curr_lock, tmp);
 272         if (test_bit(EC_FLAGS_GPE_STORM, &ec->flags)) {
 273                 /* check if we received SCI during transaction */
 274                 ec_check_sci(ec, acpi_ec_read_status(ec));
 275                 /* it is safe to enable GPE outside of transaction */
 276                 acpi_enable_gpe(NULL, ec->gpe);
 277         } else if (t->irq_count > ACPI_EC_STORM_THRESHOLD) {
 278                 pr_info(PREFIX "GPE storm detected, "
 279                         "transactions will use polling mode\n");
 280                 set_bit(EC_FLAGS_GPE_STORM, &ec->flags);
 281         }
 282         return ret;
 283 }
 284
 285 static int ec_check_ibf0(struct acpi_ec *ec)
 286 {
 287         u8 status = acpi_ec_read_status(ec);
 288         return (status & ACPI_EC_FLAG_IBF) == 0;
 289 }
 290
 291 static int ec_wait_ibf0(struct acpi_ec *ec)
 292 {
 293         unsigned long delay = jiffies + msecs_to_jiffies(ACPI_EC_DELAY);
 294         /* interrupt wait manually if GPE mode is not active */
 295         while (time_before(jiffies, delay))
 296                 if (wait_event_timeout(ec->wait, ec_check_ibf0(ec),
 297                                         msecs_to_jiffies(1)))
 298                         return 0;
 299         return -ETIME;
 300 }
 301
 302 static int acpi_ec_transaction(struct acpi_ec *ec, struct transaction *t)
 303 {
 304         int status;
 305         u32 glk;
 306         if (!ec || (!t) || (t->wlen && !t->wdata) || (t->rlen && !t->rdata))
 307                 return -EINVAL;
 308         if (t->rdata)
 309                 memset(t->rdata, 0, t->rlen);
 310         mutex_lock(&ec->lock);
 311         if (ec->global_lock) {
 312                 status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk);
 313                 if (ACPI_FAILURE(status)) {
 314                         status = -ENODEV;
 315                         goto unlock;
 316                 }
 317         }
 318         if (ec_wait_ibf0(ec)) {
 319                 pr_err(PREFIX "input buffer is not empty, "
 320                                 "aborting transaction\n");
 321                 status = -ETIME;
 322                 goto end;
 323         }
 324         status = acpi_ec_transaction_unlocked(ec, t);
 325 end:
 326         if (ec->global_lock)
 327                 acpi_release_global_lock(glk);
 328 unlock:
 329         mutex_unlock(&ec->lock);
 330         return status;
 331 }
 332
 333 static int acpi_ec_burst_enable(struct acpi_ec *ec)
 334 {
 335         u8 d;
 336         struct transaction t = {.command = ACPI_EC_BURST_ENABLE,
 337                                 .wdata = NULL, .rdata = &d,
 338                                 .wlen = 0, .rlen = 1};
 339
 340         return acpi_ec_transaction(ec, &t);
 341 }
 342
 343 static int acpi_ec_burst_disable(struct acpi_ec *ec)
 344 {
 345         struct transaction t = {.command = ACPI_EC_BURST_DISABLE,
 346                                 .wdata = NULL, .rdata = NULL,
 347                                 .wlen = 0, .rlen = 0};
 348
 349         return (acpi_ec_read_status(ec) & ACPI_EC_FLAG_BURST) ?
 350                                 acpi_ec_transaction(ec, &t) : 0;
 351 }
 352
 353 static int acpi_ec_read(struct acpi_ec *ec, u8 address, u8 * data)
 354 {
 355         int result;
 356         u8 d;
 357         struct transaction t = {.command = ACPI_EC_COMMAND_READ,
 358                                 .wdata = &address, .rdata = &d,
 359                                 .wlen = 1, .rlen = 1};
 360
 361         result = acpi_ec_transaction(ec, &t);
 362         *data = d;
 363         return result;
 364 }
 365
 366 static int acpi_ec_write(struct acpi_ec *ec, u8 address, u8 data)
 367 {
 368         u8 wdata[2] = { address, data };
 369         struct transaction t = {.command = ACPI_EC_COMMAND_WRITE,
 370                                 .wdata = wdata, .rdata = NULL,
 371                                 .wlen = 2, .rlen = 0};
 372
 373         return acpi_ec_transaction(ec, &t);
 374 }
 375
 376 /*
 377  * Externally callable EC access functions. For now, assume 1 EC only
 378  */
 379 int ec_burst_enable(void)
 380 {
 381         if (!first_ec)
 382                 return -ENODEV;
 383         return acpi_ec_burst_enable(first_ec);
 384 }
 385
 386 EXPORT_SYMBOL(ec_burst_enable);
 387
 388 int ec_burst_disable(void)
 389 {
 390         if (!first_ec)
 391                 return -ENODEV;
 392         return acpi_ec_burst_disable(first_ec);
 393 }
 394
 395 EXPORT_SYMBOL(ec_burst_disable);
 396
 397 int ec_read(u8 addr, u8 * val)
 398 {
 399         int err;
 400         u8 temp_data;
 401
 402         if (!first_ec)
 403                 return -ENODEV;
 404
 405         err = acpi_ec_read(first_ec, addr, &temp_data);
 406
 407         if (!err) {
 408                 *val = temp_data;
 409                 return 0;
 410         } else
 411                 return err;
 412 }
 413
 414 EXPORT_SYMBOL(ec_read);
 415
 416 int ec_write(u8 addr, u8 val)
 417 {
 418         int err;
 419
 420         if (!first_ec)
 421                 return -ENODEV;
 422
 423         err = acpi_ec_write(first_ec, addr, val);
 424
 425         return err;
 426 }
 427
 428 EXPORT_SYMBOL(ec_write);
 429
 430 int ec_transaction(u8 command,
 431                    const u8 * wdata, unsigned wdata_len,
 432                    u8 * rdata, unsigned rdata_len,
 433                    int force_poll)
 434 {
 435         struct transaction t = {.command = command,
 436                                 .wdata = wdata, .rdata = rdata,
 437                                 .wlen = wdata_len, .rlen = rdata_len};
 438         if (!first_ec)
 439                 return -ENODEV;
 440
 441         return acpi_ec_transaction(first_ec, &t);
 442 }
 443
 444 EXPORT_SYMBOL(ec_transaction);
 445
 446 static int acpi_ec_query(struct acpi_ec *ec, u8 * data)
 447 {
 448         int result;
 449         u8 d;
 450         struct transaction t = {.command = ACPI_EC_COMMAND_QUERY,
 451                                 .wdata = NULL, .rdata = &d,
 452                                 .wlen = 0, .rlen = 1};
 453         if (!ec || !data)
 454                 return -EINVAL;
 455
 456         /*
 457          * Query the EC to find out which _Qxx method we need to evaluate.
 458          * Note that successful completion of the query causes the ACPI_EC_SCI
 459          * bit to be cleared (and thus clearing the interrupt source).
 460          */
 461
 462         result = acpi_ec_transaction(ec, &t);
 463         if (result)
 464                 return result;
 465
 466         if (!d)
 467                 return -ENODATA;
 468
 469         *data = d;
 470         return 0;
 471 }
 472
 473 /* --------------------------------------------------------------------------
 474                                 Event Management
 475    -------------------------------------------------------------------------- */
 476 int acpi_ec_add_query_handler(struct acpi_ec *ec, u8 query_bit,
 477                               acpi_handle handle, acpi_ec_query_func func,
 478                               void *data)
 479 {
 480         struct acpi_ec_query_handler *handler =
 481             kzalloc(sizeof(struct acpi_ec_query_handler), GFP_KERNEL);
 482         if (!handler)
 483                 return -ENOMEM;
 484
 485         handler->query_bit = query_bit;
 486         handler->handle = handle;
 487         handler->func = func;
 488         handler->data = data;
 489         mutex_lock(&ec->lock);
 490         list_add(&handler->node, &ec->list);
 491         mutex_unlock(&ec->lock);
 492         return 0;
 493 }
 494
 495 EXPORT_SYMBOL_GPL(acpi_ec_add_query_handler);
 496
 497 void acpi_ec_remove_query_handler(struct acpi_ec *ec, u8 query_bit)
 498 {
 499         struct acpi_ec_query_handler *handler, *tmp;
 500         mutex_lock(&ec->lock);
 501         list_for_each_entry_safe(handler, tmp, &ec->list, node) {
 502                 if (query_bit == handler->query_bit) {
 503                         list_del(&handler->node);
 504                         kfree(handler);
 505                 }
 506         }
 507         mutex_unlock(&ec->lock);
 508 }
 509
 510 EXPORT_SYMBOL_GPL(acpi_ec_remove_query_handler);
 511
 512 static void acpi_ec_gpe_query(void *ec_cxt)
 513 {
 514         struct acpi_ec *ec = ec_cxt;
 515         u8 value = 0;
 516         struct acpi_ec_query_handler *handler, copy;
 517
 518         if (!ec || acpi_ec_query(ec, &value))
 519                 return;
 520         mutex_lock(&ec->lock);
 521         list_for_each_entry(handler, &ec->list, node) {
 522                 if (value == handler->query_bit) {
 523                         /* have custom handler for this bit */
 524                         memcpy(&copy, handler, sizeof(copy));
 525                         mutex_unlock(&ec->lock);
 526                         if (copy.func) {
 527                                 copy.func(copy.data);
 528                         } else if (copy.handle) {
 529                                 acpi_evaluate_object(copy.handle, NULL, NULL, NULL);
 530                         }
 531                         return;
 532                 }
 533         }
 534         mutex_unlock(&ec->lock);
 535 }
 536
 537 static u32 acpi_ec_gpe_handler(void *data)
 538 {
 539         struct acpi_ec *ec = data;
 540         u8 status;
 541
 542         pr_debug(PREFIX "~~~> interrupt\n");
 543         status = acpi_ec_read_status(ec);
 544
 545         advance_transaction(ec, status);
 546         if (ec_transaction_done(ec) && (status & ACPI_EC_FLAG_IBF) == 0)
 547                 wake_up(&ec->wait);
 548         ec_check_sci(ec, status);
 549         return ACPI_INTERRUPT_HANDLED;
 550 }
 551
 552 /* --------------------------------------------------------------------------
 553                              Address Space Management
 554    -------------------------------------------------------------------------- */
 555
 556 static acpi_status
 557 acpi_ec_space_handler(u32 function, acpi_physical_address address,
 558                       u32 bits, acpi_integer *value,
 559                       void *handler_context, void *region_context)
 560 {
 561         struct acpi_ec *ec = handler_context;
 562         int result = 0, i;
 563         u8 temp = 0;
 564
 565         if ((address > 0xFF) || !value || !handler_context)
 566                 return AE_BAD_PARAMETER;
 567
 568         if (function != ACPI_READ && function != ACPI_WRITE)
 569                 return AE_BAD_PARAMETER;
 570
 571         if (bits != 8 && acpi_strict)
 572                 return AE_BAD_PARAMETER;
 573
 574         if (EC_FLAGS_MSI)
 575                 acpi_ec_burst_enable(ec);
 576
 577         if (function == ACPI_READ) {
 578                 result = acpi_ec_read(ec, address, &temp);
 579                 *value = temp;
 580         } else {
 581                 temp = 0xff & (*value);
 582                 result = acpi_ec_write(ec, address, temp);
 583         }
 584
 585         for (i = 8; unlikely(bits - i > 0); i += 8) {
 586                 ++address;
 587                 if (function == ACPI_READ) {
 588                         result = acpi_ec_read(ec, address, &temp);
 589                         (*value) |= ((acpi_integer)temp) << i;
 590                 } else {
 591                         temp = 0xff & ((*value) >> i);
 592                         result = acpi_ec_write(ec, address, temp);
 593                 }
 594         }
 595
 596         if (EC_FLAGS_MSI)
 597                 acpi_ec_burst_disable(ec);
 598
 599         switch (result) {
 600         case -EINVAL:
 601                 return AE_BAD_PARAMETER;
 602                 break;
 603         case -ENODEV:
 604                 return AE_NOT_FOUND;
 605                 break;
 606         case -ETIME:
 607                 return AE_TIME;
 608                 break;
 609         default:
 610                 return AE_OK;
 611         }
 612 }
 613
 614 /* --------------------------------------------------------------------------
 615                               FS Interface (/proc)
 616    -------------------------------------------------------------------------- */
 617
 618 static struct proc_dir_entry *acpi_ec_dir;
 619
 620 static int acpi_ec_read_info(struct seq_file *seq, void *offset)
 621 {
 622         struct acpi_ec *ec = seq->private;
 623
 624         if (!ec)
 625                 goto end;
 626
 627         seq_printf(seq, "gpe:\t\t\t0x%02x\n", (u32) ec->gpe);
 628         seq_printf(seq, "ports:\t\t\t0x%02x, 0x%02x\n",
 629                    (unsigned)ec->command_addr, (unsigned)ec->data_addr);
 630         seq_printf(seq, "use global lock:\t%s\n",
 631                    ec->global_lock ? "yes" : "no");
 632       end:
 633         return 0;
 634 }
 635
 636 static int acpi_ec_info_open_fs(struct inode *inode, struct file *file)
 637 {
 638         return single_open(file, acpi_ec_read_info, PDE(inode)->data);
 639 }
 640
 641 static const struct file_operations acpi_ec_info_ops = {
 642         .open = acpi_ec_info_open_fs,
 643         .read = seq_read,
 644         .llseek = seq_lseek,
 645         .release = single_release,
 646         .owner = THIS_MODULE,
 647 };
 648
 649 static int acpi_ec_add_fs(struct acpi_device *device)
 650 {
 651         struct proc_dir_entry *entry = NULL;
 652
 653         if (!acpi_device_dir(device)) {
 654                 acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device),
 655                                                      acpi_ec_dir);
 656                 if (!acpi_device_dir(device))
 657                         return -ENODEV;
 658         }
 659
 660         entry = proc_create_data(ACPI_EC_FILE_INFO, S_IRUGO,
 661                                  acpi_device_dir(device),
 662                                  &acpi_ec_info_ops, acpi_driver_data(device));
 663         if (!entry)
 664                 return -ENODEV;
 665         return 0;
 666 }
 667
 668 static int acpi_ec_remove_fs(struct acpi_device *device)
 669 {
 670
 671         if (acpi_device_dir(device)) {
 672                 remove_proc_entry(ACPI_EC_FILE_INFO, acpi_device_dir(device));
 673                 remove_proc_entry(acpi_device_bid(device), acpi_ec_dir);
 674                 acpi_device_dir(device) = NULL;
 675         }
 676
 677         return 0;
 678 }
 679
 680 /* --------------------------------------------------------------------------
 681                                Driver Interface
 682    -------------------------------------------------------------------------- */
 683 static acpi_status
 684 ec_parse_io_ports(struct acpi_resource *resource, void *context);
 685
 686 static struct acpi_ec *make_acpi_ec(void)
 687 {
 688         struct acpi_ec *ec = kzalloc(sizeof(struct acpi_ec), GFP_KERNEL);
 689         if (!ec)
 690                 return NULL;
 691         ec->flags = 1 << EC_FLAGS_QUERY_PENDING;
 692         mutex_init(&ec->lock);
 693         init_waitqueue_head(&ec->wait);
 694         INIT_LIST_HEAD(&ec->list);
 695         spin_lock_init(&ec->curr_lock);
 696         return ec;
 697 }
 698
 699 static acpi_status
 700 acpi_ec_register_query_methods(acpi_handle handle, u32 level,
 701                                void *context, void **return_value)
 702 {
 703         char node_name[5];
 704         struct acpi_buffer buffer = { sizeof(node_name), node_name };
 705         struct acpi_ec *ec = context;
 706         int value = 0;
 707         acpi_status status;
 708
 709         status = acpi_get_name(handle, ACPI_SINGLE_NAME, &buffer);
 710
 711         if (ACPI_SUCCESS(status) && sscanf(node_name, "_Q%x", &value) == 1) {
 712                 acpi_ec_add_query_handler(ec, value, handle, NULL, NULL);
 713         }
 714         return AE_OK;
 715 }
 716
 717 static acpi_status
 718 ec_parse_device(acpi_handle handle, u32 Level, void *context, void **retval)
 719 {
 720         acpi_status status;
 721         unsigned long long tmp = 0;
 722
 723         struct acpi_ec *ec = context;
 724
 725         /* clear addr values, ec_parse_io_ports depend on it */
 726         ec->command_addr = ec->data_addr = 0;
 727
 728         status = acpi_walk_resources(handle, METHOD_NAME__CRS,
 729                                      ec_parse_io_ports, ec);
 730         if (ACPI_FAILURE(status))
 731                 return status;
 732
 733         /* Get GPE bit assignment (EC events). */
 734         /* TODO: Add support for _GPE returning a package */
 735         status = acpi_evaluate_integer(handle, "_GPE", NULL, &tmp);
 736         if (ACPI_FAILURE(status))
 737                 return status;
 738         ec->gpe = tmp;
 739         /* Use the global lock for all EC transactions? */
 740         tmp = 0;
 741         acpi_evaluate_integer(handle, "_GLK", NULL, &tmp);
 742         ec->global_lock = tmp;
 743         ec->handle = handle;
 744         return AE_CTRL_TERMINATE;
 745 }
 746
 747 static int ec_install_handlers(struct acpi_ec *ec)
 748 {
 749         acpi_status status;
 750         if (test_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags))
 751                 return 0;
 752         status = acpi_install_gpe_handler(NULL, ec->gpe,
 753                                   ACPI_GPE_EDGE_TRIGGERED,
 754                                   &acpi_ec_gpe_handler, ec);
 755         if (ACPI_FAILURE(status))
 756                 return -ENODEV;
 757         acpi_set_gpe_type(NULL, ec->gpe, ACPI_GPE_TYPE_RUNTIME);
 758         acpi_enable_gpe(NULL, ec->gpe);
 759         status = acpi_install_address_space_handler(ec->handle,
 760                                                     ACPI_ADR_SPACE_EC,
 761                                                     &acpi_ec_space_handler,
 762                                                     NULL, ec);
 763         if (ACPI_FAILURE(status)) {
 764                 if (status == AE_NOT_FOUND) {
 765                         /*
 766                          * Maybe OS fails in evaluating the _REG object.
 767                          * The AE_NOT_FOUND error will be ignored and OS
 768                          * continue to initialize EC.
 769                          */
 770                         printk(KERN_ERR "Fail in evaluating the _REG object"
 771                                 " of EC device. Broken bios is suspected.\n");
 772                 } else {
 773                         acpi_remove_gpe_handler(NULL, ec->gpe,
 774                                 &acpi_ec_gpe_handler);
 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         if (ACPI_FAILURE(acpi_remove_address_space_handler(ec->handle,
 786                                 ACPI_ADR_SPACE_EC, &acpi_ec_space_handler)))
 787                 pr_err(PREFIX "failed to remove space handler\n");
 788         if (ACPI_FAILURE(acpi_remove_gpe_handler(NULL, ec->gpe,
 789                                 &acpi_ec_gpe_handler)))
 790                 pr_err(PREFIX "failed to remove gpe handler\n");
 791         clear_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags);
 792 }
 793
 794 static int acpi_ec_add(struct acpi_device *device)
 795 {
 796         struct acpi_ec *ec = NULL;
 797         int ret;
 798
 799         strcpy(acpi_device_name(device), ACPI_EC_DEVICE_NAME);
 800         strcpy(acpi_device_class(device), ACPI_EC_CLASS);
 801
 802         /* Check for boot EC */
 803         if (boot_ec &&
 804             (boot_ec->handle == device->handle ||
 805              boot_ec->handle == ACPI_ROOT_OBJECT)) {
 806                 ec = boot_ec;
 807                 boot_ec = NULL;
 808         } else {
 809                 ec = make_acpi_ec();
 810                 if (!ec)
 811                         return -ENOMEM;
 812         }
 813         if (ec_parse_device(device->handle, 0, ec, NULL) !=
 814                 AE_CTRL_TERMINATE) {
 815                         kfree(ec);
 816                         return -EINVAL;
 817         }
 818
 819         ec->handle = device->handle;
 820
 821         /* Find and register all query methods */
 822         acpi_walk_namespace(ACPI_TYPE_METHOD, ec->handle, 1,
 823                             acpi_ec_register_query_methods, NULL, ec, NULL);
 824
 825         if (!first_ec)
 826                 first_ec = ec;
 827         device->driver_data = ec;
 828         acpi_ec_add_fs(device);
 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         acpi_ec_remove_fs(device);
 856         device->driver_data = NULL;
 857         if (ec == first_ec)
 858                 first_ec = NULL;
 859         kfree(ec);
 860         return 0;
 861 }
 862
 863 static acpi_status
 864 ec_parse_io_ports(struct acpi_resource *resource, void *context)
 865 {
 866         struct acpi_ec *ec = context;
 867
 868         if (resource->type != ACPI_RESOURCE_TYPE_IO)
 869                 return AE_OK;
 870
 871         /*
 872          * The first address region returned is the data port, and
 873          * the second address region returned is the status/command
 874          * port.
 875          */
 876         if (ec->data_addr == 0)
 877                 ec->data_addr = resource->data.io.minimum;
 878         else if (ec->command_addr == 0)
 879                 ec->command_addr = resource->data.io.minimum;
 880         else
 881                 return AE_CTRL_TERMINATE;
 882
 883         return AE_OK;
 884 }
 885
 886 int __init acpi_boot_ec_enable(void)
 887 {
 888         if (!boot_ec || test_bit(EC_FLAGS_HANDLERS_INSTALLED, &boot_ec->flags))
 889                 return 0;
 890         if (!ec_install_handlers(boot_ec)) {
 891                 first_ec = boot_ec;
 892                 return 0;
 893         }
 894         return -EFAULT;
 895 }
 896
 897 static const struct acpi_device_id ec_device_ids[] = {
 898         {"PNP0C09", 0},
 899         {"", 0},
 900 };
 901
 902 /* Some BIOS do not survive early DSDT scan, skip it */
 903 static int ec_skip_dsdt_scan(const struct dmi_system_id *id)
 904 {
 905         EC_FLAGS_SKIP_DSDT_SCAN = 1;
 906         return 0;
 907 }
 908
 909 /* ASUStek often supplies us with broken ECDT, validate it */
 910 static int ec_validate_ecdt(const struct dmi_system_id *id)
 911 {
 912         EC_FLAGS_VALIDATE_ECDT = 1;
 913         return 0;
 914 }
 915
 916 /* MSI EC needs special treatment, enable it */
 917 static int ec_flag_msi(const struct dmi_system_id *id)
 918 {
 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"),
 932         DMI_MATCH(DMI_CHASSIS_VENDOR, "MICRO-Star") }, NULL},
 933         {
 934         ec_validate_ecdt, "ASUS hardware", {
 935         DMI_MATCH(DMI_BIOS_VENDOR, "ASUS") }, NULL},
 936         {},
 937 };
 938
 939
 940 int __init acpi_ec_ecdt_probe(void)
 941 {
 942         acpi_status status;
 943         struct acpi_ec *saved_ec = NULL;
 944         struct acpi_table_ecdt *ecdt_ptr;
 945
 946         boot_ec = make_acpi_ec();
 947         if (!boot_ec)
 948                 return -ENOMEM;
 949         /*
 950          * Generate a boot ec context
 951          */
 952         dmi_check_system(ec_dmi_table);
 953         status = acpi_get_table(ACPI_SIG_ECDT, 1,
 954                                 (struct acpi_table_header **)&ecdt_ptr);
 955         if (ACPI_SUCCESS(status)) {
 956                 pr_info(PREFIX "EC description table is found, configuring boot EC\n");
 957                 boot_ec->command_addr = ecdt_ptr->control.address;
 958                 boot_ec->data_addr = ecdt_ptr->data.address;
 959                 boot_ec->gpe = ecdt_ptr->gpe;
 960                 boot_ec->handle = ACPI_ROOT_OBJECT;
 961                 acpi_get_handle(ACPI_ROOT_OBJECT, ecdt_ptr->id, &boot_ec->handle);
 962                 /* Don't trust ECDT, which comes from ASUSTek */
 963                 if (!EC_FLAGS_VALIDATE_ECDT)
 964                         goto install;
 965                 saved_ec = kmalloc(sizeof(struct acpi_ec), GFP_KERNEL);
 966                 if (!saved_ec)
 967                         return -ENOMEM;
 968                 memcpy(saved_ec, boot_ec, sizeof(struct acpi_ec));
 969         /* fall through */
 970         }
 971
 972         if (EC_FLAGS_SKIP_DSDT_SCAN)
 973                 return -ENODEV;
 974
 975         /* This workaround is needed only on some broken machines,
 976          * which require early EC, but fail to provide ECDT */
 977         printk(KERN_DEBUG PREFIX "Look up EC in DSDT\n");
 978         status = acpi_get_devices(ec_device_ids[0].id, ec_parse_device,
 979                                         boot_ec, NULL);
 980         /* Check that acpi_get_devices actually find something */
 981         if (ACPI_FAILURE(status) || !boot_ec->handle)
 982                 goto error;
 983         if (saved_ec) {
 984                 /* try to find good ECDT from ASUSTek */
 985                 if (saved_ec->command_addr != boot_ec->command_addr ||
 986                     saved_ec->data_addr != boot_ec->data_addr ||
 987                     saved_ec->gpe != boot_ec->gpe ||
 988                     saved_ec->handle != boot_ec->handle)
 989                         pr_info(PREFIX "ASUSTek keeps feeding us with broken "
 990                         "ECDT tables, which are very hard to workaround. "
 991                         "Trying to use DSDT EC info instead. Please send "
 992                         "output of acpidump to linux-acpi@vger.kernel.org\n");
 993                 kfree(saved_ec);
 994                 saved_ec = NULL;
 995         } else {
 996                 /* We really need to limit this workaround, the only ASUS,
 997                 * which needs it, has fake EC._INI method, so use it as flag.
 998                 * Keep boot_ec struct as it will be needed soon.
 999                 */
1000                 acpi_handle dummy;
1001                 if (!dmi_name_in_vendors("ASUS") ||
1002                     ACPI_FAILURE(acpi_get_handle(boot_ec->handle, "_INI",
1003                                                         &dummy)))
1004                         return -ENODEV;
1005         }
1006 install:
1007         if (!ec_install_handlers(boot_ec)) {
1008                 first_ec = boot_ec;
1009                 return 0;
1010         }
1011 error:
1012         kfree(boot_ec);
1013         boot_ec = NULL;
1014         return -ENODEV;
1015 }
1016
1017 static int acpi_ec_suspend(struct acpi_device *device, pm_message_t state)
1018 {
1019         struct acpi_ec *ec = acpi_driver_data(device);
1020         /* Stop using GPE */
1021         acpi_disable_gpe(NULL, ec->gpe);
1022         return 0;
1023 }
1024
1025 static int acpi_ec_resume(struct acpi_device *device)
1026 {
1027         struct acpi_ec *ec = acpi_driver_data(device);
1028         /* Enable use of GPE back */
1029         acpi_enable_gpe(NULL, ec->gpe);
1030         return 0;
1031 }
1032
1033 static struct acpi_driver acpi_ec_driver = {
1034         .name = "ec",
1035         .class = ACPI_EC_CLASS,
1036         .ids = ec_device_ids,
1037         .ops = {
1038                 .add = acpi_ec_add,
1039                 .remove = acpi_ec_remove,
1040                 .suspend = acpi_ec_suspend,
1041                 .resume = acpi_ec_resume,
1042                 },
1043 };
1044
1045 int __init acpi_ec_init(void)
1046 {
1047         int result = 0;
1048
1049         acpi_ec_dir = proc_mkdir(ACPI_EC_CLASS, acpi_root_dir);
1050         if (!acpi_ec_dir)
1051                 return -ENODEV;
1052
1053         /* Now register the driver for the EC */
1054         result = acpi_bus_register_driver(&acpi_ec_driver);
1055         if (result < 0) {
1056                 remove_proc_entry(ACPI_EC_CLASS, acpi_root_dir);
1057                 return -ENODEV;
1058         }
1059
1060         return result;
1061 }
1062
1063 /* EC driver currently not unloadable */
1064 #if 0
1065 static void __exit acpi_ec_exit(void)
1066 {
1067
1068         acpi_bus_unregister_driver(&acpi_ec_driver);
1069
1070         remove_proc_entry(ACPI_EC_CLASS, acpi_root_dir);
1071
1072         return;
1073 }
1074 #endif  /* 0 */