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
  46 #define ACPI_EC_CLASS                   "embedded_controller"
  47 #define ACPI_EC_DEVICE_NAME             "Embedded Controller"
  48 #define ACPI_EC_FILE_INFO               "info"
  49
  50 #undef PREFIX
  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
 123 /* --------------------------------------------------------------------------
 124                              Transaction Management
 125    -------------------------------------------------------------------------- */
 126
 127 static inline u8 acpi_ec_read_status(struct acpi_ec *ec)
 128 {
 129         u8 x = inb(ec->command_addr);
 130         pr_debug(PREFIX "---> status = 0x%2.2x\n", x);
 131         return x;
 132 }
 133
 134 static inline u8 acpi_ec_read_data(struct acpi_ec *ec)
 135 {
 136         u8 x = inb(ec->data_addr);
 137         pr_debug(PREFIX "---> data = 0x%2.2x\n", x);
 138         return x;
 139 }
 140
 141 static inline void acpi_ec_write_cmd(struct acpi_ec *ec, u8 command)
 142 {
 143         pr_debug(PREFIX "<--- command = 0x%2.2x\n", command);
 144         outb(command, ec->command_addr);
 145 }
 146
 147 static inline void acpi_ec_write_data(struct acpi_ec *ec, u8 data)
 148 {
 149         pr_debug(PREFIX "<--- data = 0x%2.2x\n", data);
 150         outb(data, ec->data_addr);
 151 }
 152
 153 static int ec_transaction_done(struct acpi_ec *ec)
 154 {
 155         unsigned long flags;
 156         int ret = 0;
 157         spin_lock_irqsave(&ec->curr_lock, flags);
 158         if (!ec->curr || ec->curr->done)
 159                 ret = 1;
 160         spin_unlock_irqrestore(&ec->curr_lock, flags);
 161         return ret;
 162 }
 163
 164 static void start_transaction(struct acpi_ec *ec)
 165 {
 166         ec->curr->irq_count = ec->curr->wi = ec->curr->ri = 0;
 167         ec->curr->done = false;
 168         acpi_ec_write_cmd(ec, ec->curr->command);
 169 }
 170
 171 static void advance_transaction(struct acpi_ec *ec, u8 status)
 172 {
 173         unsigned long flags;
 174         spin_lock_irqsave(&ec->curr_lock, flags);
 175         if (!ec->curr)
 176                 goto unlock;
 177         if (ec->curr->wlen > ec->curr->wi) {
 178                 if ((status & ACPI_EC_FLAG_IBF) == 0)
 179                         acpi_ec_write_data(ec,
 180                                 ec->curr->wdata[ec->curr->wi++]);
 181                 else
 182                         goto err;
 183         } else if (ec->curr->rlen > ec->curr->ri) {
 184                 if ((status & ACPI_EC_FLAG_OBF) == 1) {
 185                         ec->curr->rdata[ec->curr->ri++] = acpi_ec_read_data(ec);
 186                         if (ec->curr->rlen == ec->curr->ri)
 187                                 ec->curr->done = true;
 188                 } else
 189                         goto err;
 190         } else if (ec->curr->wlen == ec->curr->wi &&
 191                    (status & ACPI_EC_FLAG_IBF) == 0)
 192                 ec->curr->done = true;
 193         goto unlock;
 194 err:
 195         /* false interrupt, state didn't change */
 196         if (in_interrupt())
 197                 ++ec->curr->irq_count;
 198 unlock:
 199         spin_unlock_irqrestore(&ec->curr_lock, flags);
 200 }
 201
 202 static void acpi_ec_gpe_query(void *ec_cxt);
 203
 204 static int ec_check_sci(struct acpi_ec *ec, u8 state)
 205 {
 206         if (state & ACPI_EC_FLAG_SCI) {
 207                 if (!test_and_set_bit(EC_FLAGS_QUERY_PENDING, &ec->flags))
 208                         return acpi_os_execute(OSL_EC_BURST_HANDLER,
 209                                 acpi_ec_gpe_query, ec);
 210         }
 211         return 0;
 212 }
 213
 214 static int ec_poll(struct acpi_ec *ec)
 215 {
 216         unsigned long flags;
 217         int repeat = 2; /* number of command restarts */
 218         while (repeat--) {
 219                 unsigned long delay = jiffies +
 220                         msecs_to_jiffies(ACPI_EC_DELAY);
 221                 do {
 222                         /* don't sleep with disabled interrupts */
 223                         if (EC_FLAGS_MSI || irqs_disabled()) {
 224                                 udelay(ACPI_EC_MSI_UDELAY);
 225                                 if (ec_transaction_done(ec))
 226                                         return 0;
 227                         } else {
 228                                 if (wait_event_timeout(ec->wait,
 229                                                 ec_transaction_done(ec),
 230                                                 msecs_to_jiffies(1)))
 231                                         return 0;
 232                         }
 233                         advance_transaction(ec, acpi_ec_read_status(ec));
 234                 } while (time_before(jiffies, delay));
 235                 if (!ec->curr->irq_count ||
 236                     (acpi_ec_read_status(ec) & ACPI_EC_FLAG_IBF))
 237                         break;
 238                 /* try restart command if we get any false interrupts */
 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 /*
 334  * Note: samsung nv5000 doesn't work with ec burst mode.
 335  * http://bugzilla.kernel.org/show_bug.cgi?id=4980
 336  */
 337 static int acpi_ec_burst_enable(struct acpi_ec *ec)
 338 {
 339         u8 d;
 340         struct transaction t = {.command = ACPI_EC_BURST_ENABLE,
 341                                 .wdata = NULL, .rdata = &d,
 342                                 .wlen = 0, .rlen = 1};
 343
 344         return acpi_ec_transaction(ec, &t);
 345 }
 346
 347 static int acpi_ec_burst_disable(struct acpi_ec *ec)
 348 {
 349         struct transaction t = {.command = ACPI_EC_BURST_DISABLE,
 350                                 .wdata = NULL, .rdata = NULL,
 351                                 .wlen = 0, .rlen = 0};
 352
 353         return (acpi_ec_read_status(ec) & ACPI_EC_FLAG_BURST) ?
 354                                 acpi_ec_transaction(ec, &t) : 0;
 355 }
 356
 357 static int acpi_ec_read(struct acpi_ec *ec, u8 address, u8 * data)
 358 {
 359         int result;
 360         u8 d;
 361         struct transaction t = {.command = ACPI_EC_COMMAND_READ,
 362                                 .wdata = &address, .rdata = &d,
 363                                 .wlen = 1, .rlen = 1};
 364
 365         result = acpi_ec_transaction(ec, &t);
 366         *data = d;
 367         return result;
 368 }
 369
 370 static int acpi_ec_write(struct acpi_ec *ec, u8 address, u8 data)
 371 {
 372         u8 wdata[2] = { address, data };
 373         struct transaction t = {.command = ACPI_EC_COMMAND_WRITE,
 374                                 .wdata = wdata, .rdata = NULL,
 375                                 .wlen = 2, .rlen = 0};
 376
 377         return acpi_ec_transaction(ec, &t);
 378 }
 379
 380 /*
 381  * Externally callable EC access functions. For now, assume 1 EC only
 382  */
 383 int ec_burst_enable(void)
 384 {
 385         if (!first_ec)
 386                 return -ENODEV;
 387         return acpi_ec_burst_enable(first_ec);
 388 }
 389
 390 EXPORT_SYMBOL(ec_burst_enable);
 391
 392 int ec_burst_disable(void)
 393 {
 394         if (!first_ec)
 395                 return -ENODEV;
 396         return acpi_ec_burst_disable(first_ec);
 397 }
 398
 399 EXPORT_SYMBOL(ec_burst_disable);
 400
 401 int ec_read(u8 addr, u8 * val)
 402 {
 403         int err;
 404         u8 temp_data;
 405
 406         if (!first_ec)
 407                 return -ENODEV;
 408
 409         err = acpi_ec_read(first_ec, addr, &temp_data);
 410
 411         if (!err) {
 412                 *val = temp_data;
 413                 return 0;
 414         } else
 415                 return err;
 416 }
 417
 418 EXPORT_SYMBOL(ec_read);
 419
 420 int ec_write(u8 addr, u8 val)
 421 {
 422         int err;
 423
 424         if (!first_ec)
 425                 return -ENODEV;
 426
 427         err = acpi_ec_write(first_ec, addr, val);
 428
 429         return err;
 430 }
 431
 432 EXPORT_SYMBOL(ec_write);
 433
 434 int ec_transaction(u8 command,
 435                    const u8 * wdata, unsigned wdata_len,
 436                    u8 * rdata, unsigned rdata_len,
 437                    int force_poll)
 438 {
 439         struct transaction t = {.command = command,
 440                                 .wdata = wdata, .rdata = rdata,
 441                                 .wlen = wdata_len, .rlen = rdata_len};
 442         if (!first_ec)
 443                 return -ENODEV;
 444
 445         return acpi_ec_transaction(first_ec, &t);
 446 }
 447
 448 EXPORT_SYMBOL(ec_transaction);
 449
 450 static int acpi_ec_query(struct acpi_ec *ec, u8 * data)
 451 {
 452         int result;
 453         u8 d;
 454         struct transaction t = {.command = ACPI_EC_COMMAND_QUERY,
 455                                 .wdata = NULL, .rdata = &d,
 456                                 .wlen = 0, .rlen = 1};
 457         if (!ec || !data)
 458                 return -EINVAL;
 459
 460         /*
 461          * Query the EC to find out which _Qxx method we need to evaluate.
 462          * Note that successful completion of the query causes the ACPI_EC_SCI
 463          * bit to be cleared (and thus clearing the interrupt source).
 464          */
 465
 466         result = acpi_ec_transaction(ec, &t);
 467         if (result)
 468                 return result;
 469
 470         if (!d)
 471                 return -ENODATA;
 472
 473         *data = d;
 474         return 0;
 475 }
 476
 477 /* --------------------------------------------------------------------------
 478                                 Event Management
 479    -------------------------------------------------------------------------- */
 480 int acpi_ec_add_query_handler(struct acpi_ec *ec, u8 query_bit,
 481                               acpi_handle handle, acpi_ec_query_func func,
 482                               void *data)
 483 {
 484         struct acpi_ec_query_handler *handler =
 485             kzalloc(sizeof(struct acpi_ec_query_handler), GFP_KERNEL);
 486         if (!handler)
 487                 return -ENOMEM;
 488
 489         handler->query_bit = query_bit;
 490         handler->handle = handle;
 491         handler->func = func;
 492         handler->data = data;
 493         mutex_lock(&ec->lock);
 494         list_add(&handler->node, &ec->list);
 495         mutex_unlock(&ec->lock);
 496         return 0;
 497 }
 498
 499 EXPORT_SYMBOL_GPL(acpi_ec_add_query_handler);
 500
 501 void acpi_ec_remove_query_handler(struct acpi_ec *ec, u8 query_bit)
 502 {
 503         struct acpi_ec_query_handler *handler, *tmp;
 504         mutex_lock(&ec->lock);
 505         list_for_each_entry_safe(handler, tmp, &ec->list, node) {
 506                 if (query_bit == handler->query_bit) {
 507                         list_del(&handler->node);
 508                         kfree(handler);
 509                 }
 510         }
 511         mutex_unlock(&ec->lock);
 512 }
 513
 514 EXPORT_SYMBOL_GPL(acpi_ec_remove_query_handler);
 515
 516 static void acpi_ec_gpe_query(void *ec_cxt)
 517 {
 518         struct acpi_ec *ec = ec_cxt;
 519         u8 value = 0;
 520         struct acpi_ec_query_handler *handler, copy;
 521
 522         if (!ec || acpi_ec_query(ec, &value))
 523                 return;
 524         mutex_lock(&ec->lock);
 525         list_for_each_entry(handler, &ec->list, node) {
 526                 if (value == handler->query_bit) {
 527                         /* have custom handler for this bit */
 528                         memcpy(&copy, handler, sizeof(copy));
 529                         mutex_unlock(&ec->lock);
 530                         if (copy.func) {
 531                                 copy.func(copy.data);
 532                         } else if (copy.handle) {
 533                                 acpi_evaluate_object(copy.handle, NULL, NULL, NULL);
 534                         }
 535                         return;
 536                 }
 537         }
 538         mutex_unlock(&ec->lock);
 539 }
 540
 541 static u32 acpi_ec_gpe_handler(void *data)
 542 {
 543         struct acpi_ec *ec = data;
 544         u8 status;
 545
 546         pr_debug(PREFIX "~~~> interrupt\n");
 547         status = acpi_ec_read_status(ec);
 548
 549         advance_transaction(ec, status);
 550         if (ec_transaction_done(ec) && (status & ACPI_EC_FLAG_IBF) == 0)
 551                 wake_up(&ec->wait);
 552         ec_check_sci(ec, status);
 553         return ACPI_INTERRUPT_HANDLED;
 554 }
 555
 556 /* --------------------------------------------------------------------------
 557                              Address Space Management
 558    -------------------------------------------------------------------------- */
 559
 560 static acpi_status
 561 acpi_ec_space_handler(u32 function, acpi_physical_address address,
 562                       u32 bits, acpi_integer *value,
 563                       void *handler_context, void *region_context)
 564 {
 565         struct acpi_ec *ec = handler_context;
 566         int result = 0, i;
 567         u8 temp = 0;
 568
 569         if ((address > 0xFF) || !value || !handler_context)
 570                 return AE_BAD_PARAMETER;
 571
 572         if (function != ACPI_READ && function != ACPI_WRITE)
 573                 return AE_BAD_PARAMETER;
 574
 575         if (bits != 8 && acpi_strict)
 576                 return AE_BAD_PARAMETER;
 577
 578         acpi_ec_burst_enable(ec);
 579
 580         if (function == ACPI_READ) {
 581                 result = acpi_ec_read(ec, address, &temp);
 582                 *value = temp;
 583         } else {
 584                 temp = 0xff & (*value);
 585                 result = acpi_ec_write(ec, address, temp);
 586         }
 587
 588         for (i = 8; unlikely(bits - i > 0); i += 8) {
 589                 ++address;
 590                 if (function == ACPI_READ) {
 591                         result = acpi_ec_read(ec, address, &temp);
 592                         (*value) |= ((acpi_integer)temp) << i;
 593                 } else {
 594                         temp = 0xff & ((*value) >> i);
 595                         result = acpi_ec_write(ec, address, temp);
 596                 }
 597         }
 598
 599         acpi_ec_burst_disable(ec);
 600
 601         switch (result) {
 602         case -EINVAL:
 603                 return AE_BAD_PARAMETER;
 604                 break;
 605         case -ENODEV:
 606                 return AE_NOT_FOUND;
 607                 break;
 608         case -ETIME:
 609                 return AE_TIME;
 610                 break;
 611         default:
 612                 return AE_OK;
 613         }
 614 }
 615
 616 /* --------------------------------------------------------------------------
 617                               FS Interface (/proc)
 618    -------------------------------------------------------------------------- */
 619
 620 static struct proc_dir_entry *acpi_ec_dir;
 621
 622 static int acpi_ec_read_info(struct seq_file *seq, void *offset)
 623 {
 624         struct acpi_ec *ec = seq->private;
 625
 626         if (!ec)
 627                 goto end;
 628
 629         seq_printf(seq, "gpe:\t\t\t0x%02x\n", (u32) ec->gpe);
 630         seq_printf(seq, "ports:\t\t\t0x%02x, 0x%02x\n",
 631                    (unsigned)ec->command_addr, (unsigned)ec->data_addr);
 632         seq_printf(seq, "use global lock:\t%s\n",
 633                    ec->global_lock ? "yes" : "no");
 634       end:
 635         return 0;
 636 }
 637
 638 static int acpi_ec_info_open_fs(struct inode *inode, struct file *file)
 639 {
 640         return single_open(file, acpi_ec_read_info, PDE(inode)->data);
 641 }
 642
 643 static const struct file_operations acpi_ec_info_ops = {
 644         .open = acpi_ec_info_open_fs,
 645         .read = seq_read,
 646         .llseek = seq_lseek,
 647         .release = single_release,
 648         .owner = THIS_MODULE,
 649 };
 650
 651 static int acpi_ec_add_fs(struct acpi_device *device)
 652 {
 653         struct proc_dir_entry *entry = NULL;
 654
 655         if (!acpi_device_dir(device)) {
 656                 acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device),
 657                                                      acpi_ec_dir);
 658                 if (!acpi_device_dir(device))
 659                         return -ENODEV;
 660         }
 661
 662         entry = proc_create_data(ACPI_EC_FILE_INFO, S_IRUGO,
 663                                  acpi_device_dir(device),
 664                                  &acpi_ec_info_ops, acpi_driver_data(device));
 665         if (!entry)
 666                 return -ENODEV;
 667         return 0;
 668 }
 669
 670 static int acpi_ec_remove_fs(struct acpi_device *device)
 671 {
 672
 673         if (acpi_device_dir(device)) {
 674                 remove_proc_entry(ACPI_EC_FILE_INFO, acpi_device_dir(device));
 675                 remove_proc_entry(acpi_device_bid(device), acpi_ec_dir);
 676                 acpi_device_dir(device) = NULL;
 677         }
 678
 679         return 0;
 680 }
 681
 682 /* --------------------------------------------------------------------------
 683                                Driver Interface
 684    -------------------------------------------------------------------------- */
 685 static acpi_status
 686 ec_parse_io_ports(struct acpi_resource *resource, void *context);
 687
 688 static struct acpi_ec *make_acpi_ec(void)
 689 {
 690         struct acpi_ec *ec = kzalloc(sizeof(struct acpi_ec), GFP_KERNEL);
 691         if (!ec)
 692                 return NULL;
 693         ec->flags = 1 << EC_FLAGS_QUERY_PENDING;
 694         mutex_init(&ec->lock);
 695         init_waitqueue_head(&ec->wait);
 696         INIT_LIST_HEAD(&ec->list);
 697         spin_lock_init(&ec->curr_lock);
 698         return ec;
 699 }
 700
 701 static acpi_status
 702 acpi_ec_register_query_methods(acpi_handle handle, u32 level,
 703                                void *context, void **return_value)
 704 {
 705         char node_name[5];
 706         struct acpi_buffer buffer = { sizeof(node_name), node_name };
 707         struct acpi_ec *ec = context;
 708         int value = 0;
 709         acpi_status status;
 710
 711         status = acpi_get_name(handle, ACPI_SINGLE_NAME, &buffer);
 712
 713         if (ACPI_SUCCESS(status) && sscanf(node_name, "_Q%x", &value) == 1) {
 714                 acpi_ec_add_query_handler(ec, value, handle, NULL, NULL);
 715         }
 716         return AE_OK;
 717 }
 718
 719 static acpi_status
 720 ec_parse_device(acpi_handle handle, u32 Level, void *context, void **retval)
 721 {
 722         acpi_status status;
 723         unsigned long long tmp = 0;
 724
 725         struct acpi_ec *ec = context;
 726
 727         /* clear addr values, ec_parse_io_ports depend on it */
 728         ec->command_addr = ec->data_addr = 0;
 729
 730         status = acpi_walk_resources(handle, METHOD_NAME__CRS,
 731                                      ec_parse_io_ports, ec);
 732         if (ACPI_FAILURE(status))
 733                 return status;
 734
 735         /* Get GPE bit assignment (EC events). */
 736         /* TODO: Add support for _GPE returning a package */
 737         status = acpi_evaluate_integer(handle, "_GPE", NULL, &tmp);
 738         if (ACPI_FAILURE(status))
 739                 return status;
 740         ec->gpe = tmp;
 741         /* Use the global lock for all EC transactions? */
 742         tmp = 0;
 743         acpi_evaluate_integer(handle, "_GLK", NULL, &tmp);
 744         ec->global_lock = tmp;
 745         ec->handle = handle;
 746         return AE_CTRL_TERMINATE;
 747 }
 748
 749 static void ec_remove_handlers(struct acpi_ec *ec)
 750 {
 751         if (ACPI_FAILURE(acpi_remove_address_space_handler(ec->handle,
 752                                 ACPI_ADR_SPACE_EC, &acpi_ec_space_handler)))
 753                 pr_err(PREFIX "failed to remove space handler\n");
 754         if (ACPI_FAILURE(acpi_remove_gpe_handler(NULL, ec->gpe,
 755                                 &acpi_ec_gpe_handler)))
 756                 pr_err(PREFIX "failed to remove gpe handler\n");
 757         clear_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags);
 758 }
 759
 760 static int acpi_ec_add(struct acpi_device *device)
 761 {
 762         struct acpi_ec *ec = NULL;
 763
 764         if (!device)
 765                 return -EINVAL;
 766         strcpy(acpi_device_name(device), ACPI_EC_DEVICE_NAME);
 767         strcpy(acpi_device_class(device), ACPI_EC_CLASS);
 768
 769         /* Check for boot EC */
 770         if (boot_ec &&
 771             (boot_ec->handle == device->handle ||
 772              boot_ec->handle == ACPI_ROOT_OBJECT)) {
 773                 ec = boot_ec;
 774                 boot_ec = NULL;
 775         } else {
 776                 ec = make_acpi_ec();
 777                 if (!ec)
 778                         return -ENOMEM;
 779         }
 780         if (ec_parse_device(device->handle, 0, ec, NULL) !=
 781                 AE_CTRL_TERMINATE) {
 782                         kfree(ec);
 783                         return -EINVAL;
 784         }
 785
 786         ec->handle = device->handle;
 787
 788         /* Find and register all query methods */
 789         acpi_walk_namespace(ACPI_TYPE_METHOD, ec->handle, 1,
 790                             acpi_ec_register_query_methods, ec, NULL);
 791
 792         if (!first_ec)
 793                 first_ec = ec;
 794         device->driver_data = ec;
 795         acpi_ec_add_fs(device);
 796         pr_info(PREFIX "GPE = 0x%lx, I/O: command/status = 0x%lx, data = 0x%lx\n",
 797                           ec->gpe, ec->command_addr, ec->data_addr);
 798         return 0;
 799 }
 800
 801 static int acpi_ec_remove(struct acpi_device *device, int type)
 802 {
 803         struct acpi_ec *ec;
 804         struct acpi_ec_query_handler *handler, *tmp;
 805
 806         if (!device)
 807                 return -EINVAL;
 808
 809         ec = acpi_driver_data(device);
 810         mutex_lock(&ec->lock);
 811         list_for_each_entry_safe(handler, tmp, &ec->list, node) {
 812                 list_del(&handler->node);
 813                 kfree(handler);
 814         }
 815         mutex_unlock(&ec->lock);
 816         acpi_ec_remove_fs(device);
 817         device->driver_data = NULL;
 818         if (ec == first_ec)
 819                 first_ec = NULL;
 820         kfree(ec);
 821         return 0;
 822 }
 823
 824 static acpi_status
 825 ec_parse_io_ports(struct acpi_resource *resource, void *context)
 826 {
 827         struct acpi_ec *ec = context;
 828
 829         if (resource->type != ACPI_RESOURCE_TYPE_IO)
 830                 return AE_OK;
 831
 832         /*
 833          * The first address region returned is the data port, and
 834          * the second address region returned is the status/command
 835          * port.
 836          */
 837         if (ec->data_addr == 0)
 838                 ec->data_addr = resource->data.io.minimum;
 839         else if (ec->command_addr == 0)
 840                 ec->command_addr = resource->data.io.minimum;
 841         else
 842                 return AE_CTRL_TERMINATE;
 843
 844         return AE_OK;
 845 }
 846
 847 static int ec_install_handlers(struct acpi_ec *ec)
 848 {
 849         acpi_status status;
 850         if (test_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags))
 851                 return 0;
 852         status = acpi_install_gpe_handler(NULL, ec->gpe,
 853                                   ACPI_GPE_EDGE_TRIGGERED,
 854                                   &acpi_ec_gpe_handler, ec);
 855         if (ACPI_FAILURE(status))
 856                 return -ENODEV;
 857         acpi_set_gpe_type(NULL, ec->gpe, ACPI_GPE_TYPE_RUNTIME);
 858         acpi_enable_gpe(NULL, ec->gpe);
 859         status = acpi_install_address_space_handler(ec->handle,
 860                                                     ACPI_ADR_SPACE_EC,
 861                                                     &acpi_ec_space_handler,
 862                                                     NULL, ec);
 863         if (ACPI_FAILURE(status)) {
 864                 if (status == AE_NOT_FOUND) {
 865                         /*
 866                          * Maybe OS fails in evaluating the _REG object.
 867                          * The AE_NOT_FOUND error will be ignored and OS
 868                          * continue to initialize EC.
 869                          */
 870                         printk(KERN_ERR "Fail in evaluating the _REG object"
 871                                 " of EC device. Broken bios is suspected.\n");
 872                 } else {
 873                         acpi_remove_gpe_handler(NULL, ec->gpe,
 874                                 &acpi_ec_gpe_handler);
 875                         return -ENODEV;
 876                 }
 877         }
 878
 879         set_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags);
 880         return 0;
 881 }
 882
 883 static int acpi_ec_start(struct acpi_device *device)
 884 {
 885         struct acpi_ec *ec;
 886         int ret = 0;
 887
 888         if (!device)
 889                 return -EINVAL;
 890
 891         ec = acpi_driver_data(device);
 892
 893         if (!ec)
 894                 return -EINVAL;
 895
 896         ret = ec_install_handlers(ec);
 897
 898         /* EC is fully operational, allow queries */
 899         clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags);
 900         return ret;
 901 }
 902
 903 static int acpi_ec_stop(struct acpi_device *device, int type)
 904 {
 905         struct acpi_ec *ec;
 906         if (!device)
 907                 return -EINVAL;
 908         ec = acpi_driver_data(device);
 909         if (!ec)
 910                 return -EINVAL;
 911         ec_remove_handlers(ec);
 912
 913         return 0;
 914 }
 915
 916 int __init acpi_boot_ec_enable(void)
 917 {
 918         if (!boot_ec || test_bit(EC_FLAGS_HANDLERS_INSTALLED, &boot_ec->flags))
 919                 return 0;
 920         if (!ec_install_handlers(boot_ec)) {
 921                 first_ec = boot_ec;
 922                 return 0;
 923         }
 924         return -EFAULT;
 925 }
 926
 927 static const struct acpi_device_id ec_device_ids[] = {
 928         {"PNP0C09", 0},
 929         {"", 0},
 930 };
 931
 932 int __init acpi_ec_ecdt_probe(void)
 933 {
 934         acpi_status status;
 935         struct acpi_ec *saved_ec = NULL;
 936         struct acpi_table_ecdt *ecdt_ptr;
 937
 938         boot_ec = make_acpi_ec();
 939         if (!boot_ec)
 940                 return -ENOMEM;
 941         /*
 942          * Generate a boot ec context
 943          */
 944         if (dmi_name_in_vendors("Micro-Star") ||
 945             dmi_name_in_vendors("Notebook")) {
 946                 pr_info(PREFIX "Enabling special treatment for EC from MSI.\n");
 947                 EC_FLAGS_MSI = 1;
 948         }
 949         status = acpi_get_table(ACPI_SIG_ECDT, 1,
 950                                 (struct acpi_table_header **)&ecdt_ptr);
 951         if (ACPI_SUCCESS(status)) {
 952                 pr_info(PREFIX "EC description table is found, configuring boot EC\n");
 953                 boot_ec->command_addr = ecdt_ptr->control.address;
 954                 boot_ec->data_addr = ecdt_ptr->data.address;
 955                 boot_ec->gpe = ecdt_ptr->gpe;
 956                 boot_ec->handle = ACPI_ROOT_OBJECT;
 957                 acpi_get_handle(ACPI_ROOT_OBJECT, ecdt_ptr->id, &boot_ec->handle);
 958                 /* Don't trust ECDT, which comes from ASUSTek */
 959                 if (!dmi_name_in_vendors("ASUS") && EC_FLAGS_MSI == 0)
 960                         goto install;
 961                 saved_ec = kmalloc(sizeof(struct acpi_ec), GFP_KERNEL);
 962                 if (!saved_ec)
 963                         return -ENOMEM;
 964                 memcpy(saved_ec, boot_ec, sizeof(struct acpi_ec));
 965         /* fall through */
 966         }
 967         /* This workaround is needed only on some broken machines,
 968          * which require early EC, but fail to provide ECDT */
 969         printk(KERN_DEBUG PREFIX "Look up EC in DSDT\n");
 970         status = acpi_get_devices(ec_device_ids[0].id, ec_parse_device,
 971                                         boot_ec, NULL);
 972         /* Check that acpi_get_devices actually find something */
 973         if (ACPI_FAILURE(status) || !boot_ec->handle)
 974                 goto error;
 975         if (saved_ec) {
 976                 /* try to find good ECDT from ASUSTek */
 977                 if (saved_ec->command_addr != boot_ec->command_addr ||
 978                     saved_ec->data_addr != boot_ec->data_addr ||
 979                     saved_ec->gpe != boot_ec->gpe ||
 980                     saved_ec->handle != boot_ec->handle)
 981                         pr_info(PREFIX "ASUSTek keeps feeding us with broken "
 982                         "ECDT tables, which are very hard to workaround. "
 983                         "Trying to use DSDT EC info instead. Please send "
 984                         "output of acpidump to linux-acpi@vger.kernel.org\n");
 985                 kfree(saved_ec);
 986                 saved_ec = NULL;
 987         } else {
 988                 /* We really need to limit this workaround, the only ASUS,
 989                 * which needs it, has fake EC._INI method, so use it as flag.
 990                 * Keep boot_ec struct as it will be needed soon.
 991                 */
 992                 acpi_handle dummy;
 993                 if (!dmi_name_in_vendors("ASUS") ||
 994                     ACPI_FAILURE(acpi_get_handle(boot_ec->handle, "_INI",
 995                                                         &dummy)))
 996                         return -ENODEV;
 997         }
 998 install:
 999         if (!ec_install_handlers(boot_ec)) {
1000                 first_ec = boot_ec;
1001                 return 0;
1002         }
1003 error:
1004         kfree(boot_ec);
1005         boot_ec = NULL;
1006         return -ENODEV;
1007 }
1008
1009 static int acpi_ec_suspend(struct acpi_device *device, pm_message_t state)
1010 {
1011         struct acpi_ec *ec = acpi_driver_data(device);
1012         /* Stop using GPE */
1013         acpi_disable_gpe(NULL, ec->gpe);
1014         return 0;
1015 }
1016
1017 static int acpi_ec_resume(struct acpi_device *device)
1018 {
1019         struct acpi_ec *ec = acpi_driver_data(device);
1020         /* Enable use of GPE back */
1021         acpi_enable_gpe(NULL, ec->gpe);
1022         return 0;
1023 }
1024
1025 static struct acpi_driver acpi_ec_driver = {
1026         .name = "ec",
1027         .class = ACPI_EC_CLASS,
1028         .ids = ec_device_ids,
1029         .ops = {
1030                 .add = acpi_ec_add,
1031                 .remove = acpi_ec_remove,
1032                 .start = acpi_ec_start,
1033                 .stop = acpi_ec_stop,
1034                 .suspend = acpi_ec_suspend,
1035                 .resume = acpi_ec_resume,
1036                 },
1037 };
1038
1039 int __init acpi_ec_init(void)
1040 {
1041         int result = 0;
1042
1043         acpi_ec_dir = proc_mkdir(ACPI_EC_CLASS, acpi_root_dir);
1044         if (!acpi_ec_dir)
1045                 return -ENODEV;
1046
1047         /* Now register the driver for the EC */
1048         result = acpi_bus_register_driver(&acpi_ec_driver);
1049         if (result < 0) {
1050                 remove_proc_entry(ACPI_EC_CLASS, acpi_root_dir);
1051                 return -ENODEV;
1052         }
1053
1054         return result;
1055 }
1056
1057 /* EC driver currently not unloadable */
1058 #if 0
1059 static void __exit acpi_ec_exit(void)
1060 {
1061
1062         acpi_bus_unregister_driver(&acpi_ec_driver);
1063
1064         remove_proc_entry(ACPI_EC_CLASS, acpi_root_dir);
1065
1066         return;
1067 }
1068 #endif  /* 0 */