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 #define PREFIX                          "ACPI: EC: "
  51
  52 /* EC status register */
  53 #define ACPI_EC_FLAG_OBF        0x01    /* Output buffer full */
  54 #define ACPI_EC_FLAG_IBF        0x02    /* Input buffer full */
  55 #define ACPI_EC_FLAG_BURST      0x10    /* burst mode */
  56 #define ACPI_EC_FLAG_SCI        0x20    /* EC-SCI occurred */
  57
  58 /* EC commands */
  59 enum ec_command {
  60         ACPI_EC_COMMAND_READ = 0x80,
  61         ACPI_EC_COMMAND_WRITE = 0x81,
  62         ACPI_EC_BURST_ENABLE = 0x82,
  63         ACPI_EC_BURST_DISABLE = 0x83,
  64         ACPI_EC_COMMAND_QUERY = 0x84,
  65 };
  66
  67 #define ACPI_EC_DELAY           500     /* Wait 500ms max. during EC ops */
  68 #define ACPI_EC_UDELAY_GLK      1000    /* Wait 1ms max. to get global lock */
  69 #define ACPI_EC_CDELAY          10      /* Wait 10us before polling EC */
  70 #define ACPI_EC_MSI_UDELAY      550     /* Wait 550us for MSI EC */
  71
  72 #define ACPI_EC_STORM_THRESHOLD 8       /* number of false interrupts
  73                                            per one transaction */
  74
  75 enum {
  76         EC_FLAGS_QUERY_PENDING,         /* Query is pending */
  77         EC_FLAGS_GPE_STORM,             /* GPE storm detected */
  78         EC_FLAGS_HANDLERS_INSTALLED     /* Handlers for GPE and
  79                                          * OpReg are installed */
  80 };
  81
  82 /* If we find an EC via the ECDT, we need to keep a ptr to its context */
  83 /* External interfaces use first EC only, so remember */
  84 typedef int (*acpi_ec_query_func) (void *data);
  85
  86 struct acpi_ec_query_handler {
  87         struct list_head node;
  88         acpi_ec_query_func func;
  89         acpi_handle handle;
  90         void *data;
  91         u8 query_bit;
  92 };
  93
  94 struct transaction {
  95         const u8 *wdata;
  96         u8 *rdata;
  97         unsigned short irq_count;
  98         u8 command;
  99         u8 wi;
 100         u8 ri;
 101         u8 wlen;
 102         u8 rlen;
 103         bool done;
 104 };
 105
 106 static struct acpi_ec {
 107         acpi_handle handle;
 108         unsigned long gpe;
 109         unsigned long command_addr;
 110         unsigned long data_addr;
 111         unsigned long global_lock;
 112         unsigned long flags;
 113         struct mutex lock;
 114         wait_queue_head_t wait;
 115         struct list_head list;
 116         struct transaction *curr;
 117         spinlock_t curr_lock;
 118 } *boot_ec, *first_ec;
 119
 120 static int EC_FLAGS_MSI; /* Out-of-spec MSI controller */
 121
 122 /* --------------------------------------------------------------------------
 123                              Transaction Management
 124    -------------------------------------------------------------------------- */
 125
 126 static inline u8 acpi_ec_read_status(struct acpi_ec *ec)
 127 {
 128         u8 x = inb(ec->command_addr);
 129         pr_debug(PREFIX "---> status = 0x%2.2x\n", x);
 130         return x;
 131 }
 132
 133 static inline u8 acpi_ec_read_data(struct acpi_ec *ec)
 134 {
 135         u8 x = inb(ec->data_addr);
 136         pr_debug(PREFIX "---> data = 0x%2.2x\n", x);
 137         return x;
 138 }
 139
 140 static inline void acpi_ec_write_cmd(struct acpi_ec *ec, u8 command)
 141 {
 142         pr_debug(PREFIX "<--- command = 0x%2.2x\n", command);
 143         outb(command, ec->command_addr);
 144 }
 145
 146 static inline void acpi_ec_write_data(struct acpi_ec *ec, u8 data)
 147 {
 148         pr_debug(PREFIX "<--- data = 0x%2.2x\n", data);
 149         outb(data, ec->data_addr);
 150 }
 151
 152 static int ec_transaction_done(struct acpi_ec *ec)
 153 {
 154         unsigned long flags;
 155         int ret = 0;
 156         spin_lock_irqsave(&ec->curr_lock, flags);
 157         if (!ec->curr || ec->curr->done)
 158                 ret = 1;
 159         spin_unlock_irqrestore(&ec->curr_lock, flags);
 160         return ret;
 161 }
 162
 163 static void start_transaction(struct acpi_ec *ec)
 164 {
 165         ec->curr->irq_count = ec->curr->wi = ec->curr->ri = 0;
 166         ec->curr->done = false;
 167         acpi_ec_write_cmd(ec, ec->curr->command);
 168 }
 169
 170 static void advance_transaction(struct acpi_ec *ec, u8 status)
 171 {
 172         unsigned long flags;
 173         spin_lock_irqsave(&ec->curr_lock, flags);
 174         if (!ec->curr)
 175                 goto unlock;
 176         if (ec->curr->wlen > ec->curr->wi) {
 177                 if ((status & ACPI_EC_FLAG_IBF) == 0)
 178                         acpi_ec_write_data(ec,
 179                                 ec->curr->wdata[ec->curr->wi++]);
 180                 else
 181                         goto err;
 182         } else if (ec->curr->rlen > ec->curr->ri) {
 183                 if ((status & ACPI_EC_FLAG_OBF) == 1) {
 184                         ec->curr->rdata[ec->curr->ri++] = acpi_ec_read_data(ec);
 185                         if (ec->curr->rlen == ec->curr->ri)
 186                                 ec->curr->done = true;
 187                 } else
 188                         goto err;
 189         } else if (ec->curr->wlen == ec->curr->wi &&
 190                    (status & ACPI_EC_FLAG_IBF) == 0)
 191                 ec->curr->done = true;
 192         goto unlock;
 193 err:
 194         /* false interrupt, state didn't change */
 195         if (in_interrupt())
 196                 ++ec->curr->irq_count;
 197 unlock:
 198         spin_unlock_irqrestore(&ec->curr_lock, flags);
 199 }
 200
 201 static void acpi_ec_gpe_query(void *ec_cxt);
 202
 203 static int ec_check_sci(struct acpi_ec *ec, u8 state)
 204 {
 205         if (state & ACPI_EC_FLAG_SCI) {
 206                 if (!test_and_set_bit(EC_FLAGS_QUERY_PENDING, &ec->flags))
 207                         return acpi_os_execute(OSL_EC_BURST_HANDLER,
 208                                 acpi_ec_gpe_query, ec);
 209         }
 210         return 0;
 211 }
 212
 213 static int ec_poll(struct acpi_ec *ec)
 214 {
 215         unsigned long flags;
 216         int repeat = 2; /* number of command restarts */
 217         while (repeat--) {
 218                 unsigned long delay = jiffies +
 219                         msecs_to_jiffies(ACPI_EC_DELAY);
 220                 do {
 221                         /* don't sleep with disabled interrupts */
 222                         if (EC_FLAGS_MSI || irqs_disabled()) {
 223                                 udelay(ACPI_EC_MSI_UDELAY);
 224                                 if (ec_transaction_done(ec))
 225                                         return 0;
 226                         } else {
 227                                 if (wait_event_timeout(ec->wait,
 228                                                 ec_transaction_done(ec),
 229                                                 msecs_to_jiffies(1)))
 230                                         return 0;
 231                         }
 232                         advance_transaction(ec, acpi_ec_read_status(ec));
 233                 } while (time_before(jiffies, delay));
 234                 if (!ec->curr->irq_count ||
 235                     (acpi_ec_read_status(ec) & ACPI_EC_FLAG_IBF))
 236                         break;
 237                 /* try restart command if we get any false interrupts */
 238                 pr_debug(PREFIX "controller reset, restart transaction\n");
 239                 spin_lock_irqsave(&ec->curr_lock, flags);
 240                 start_transaction(ec);
 241                 spin_unlock_irqrestore(&ec->curr_lock, flags);
 242         }
 243         return -ETIME;
 244 }
 245
 246 static int acpi_ec_transaction_unlocked(struct acpi_ec *ec,
 247                                         struct transaction *t)
 248 {
 249         unsigned long tmp;
 250         int ret = 0;
 251         pr_debug(PREFIX "transaction start\n");
 252         /* disable GPE during transaction if storm is detected */
 253         if (test_bit(EC_FLAGS_GPE_STORM, &ec->flags)) {
 254                 acpi_disable_gpe(NULL, ec->gpe);
 255         }
 256         if (EC_FLAGS_MSI)
 257                 udelay(ACPI_EC_MSI_UDELAY);
 258         /* start transaction */
 259         spin_lock_irqsave(&ec->curr_lock, tmp);
 260         /* following two actions should be kept atomic */
 261         ec->curr = t;
 262         start_transaction(ec);
 263         if (ec->curr->command == ACPI_EC_COMMAND_QUERY)
 264                 clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags);
 265         spin_unlock_irqrestore(&ec->curr_lock, tmp);
 266         ret = ec_poll(ec);
 267         pr_debug(PREFIX "transaction end\n");
 268         spin_lock_irqsave(&ec->curr_lock, tmp);
 269         ec->curr = NULL;
 270         spin_unlock_irqrestore(&ec->curr_lock, tmp);
 271         if (test_bit(EC_FLAGS_GPE_STORM, &ec->flags)) {
 272                 /* check if we received SCI during transaction */
 273                 ec_check_sci(ec, acpi_ec_read_status(ec));
 274                 /* it is safe to enable GPE outside of transaction */
 275                 acpi_enable_gpe(NULL, ec->gpe);
 276         } else if (t->irq_count > ACPI_EC_STORM_THRESHOLD) {
 277                 pr_info(PREFIX "GPE storm detected, "
 278                         "transactions will use polling mode\n");
 279                 set_bit(EC_FLAGS_GPE_STORM, &ec->flags);
 280         }
 281         return ret;
 282 }
 283
 284 static int ec_check_ibf0(struct acpi_ec *ec)
 285 {
 286         u8 status = acpi_ec_read_status(ec);
 287         return (status & ACPI_EC_FLAG_IBF) == 0;
 288 }
 289
 290 static int ec_wait_ibf0(struct acpi_ec *ec)
 291 {
 292         unsigned long delay = jiffies + msecs_to_jiffies(ACPI_EC_DELAY);
 293         /* interrupt wait manually if GPE mode is not active */
 294         while (time_before(jiffies, delay))
 295                 if (wait_event_timeout(ec->wait, ec_check_ibf0(ec),
 296                                         msecs_to_jiffies(1)))
 297                         return 0;
 298         return -ETIME;
 299 }
 300
 301 static int acpi_ec_transaction(struct acpi_ec *ec, struct transaction *t)
 302 {
 303         int status;
 304         u32 glk;
 305         if (!ec || (!t) || (t->wlen && !t->wdata) || (t->rlen && !t->rdata))
 306                 return -EINVAL;
 307         if (t->rdata)
 308                 memset(t->rdata, 0, t->rlen);
 309         mutex_lock(&ec->lock);
 310         if (ec->global_lock) {
 311                 status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk);
 312                 if (ACPI_FAILURE(status)) {
 313                         status = -ENODEV;
 314                         goto unlock;
 315                 }
 316         }
 317         if (ec_wait_ibf0(ec)) {
 318                 pr_err(PREFIX "input buffer is not empty, "
 319                                 "aborting transaction\n");
 320                 status = -ETIME;
 321                 goto end;
 322         }
 323         status = acpi_ec_transaction_unlocked(ec, t);
 324 end:
 325         if (ec->global_lock)
 326                 acpi_release_global_lock(glk);
 327 unlock:
 328         mutex_unlock(&ec->lock);
 329         return status;
 330 }
 331
 332 static int acpi_ec_burst_enable(struct acpi_ec *ec)
 333 {
 334         u8 d;
 335         struct transaction t = {.command = ACPI_EC_BURST_ENABLE,
 336                                 .wdata = NULL, .rdata = &d,
 337                                 .wlen = 0, .rlen = 1};
 338
 339         return acpi_ec_transaction(ec, &t);
 340 }
 341
 342 static int acpi_ec_burst_disable(struct acpi_ec *ec)
 343 {
 344         struct transaction t = {.command = ACPI_EC_BURST_DISABLE,
 345                                 .wdata = NULL, .rdata = NULL,
 346                                 .wlen = 0, .rlen = 0};
 347
 348         return (acpi_ec_read_status(ec) & ACPI_EC_FLAG_BURST) ?
 349                                 acpi_ec_transaction(ec, &t) : 0;
 350 }
 351
 352 static int acpi_ec_read(struct acpi_ec *ec, u8 address, u8 * data)
 353 {
 354         int result;
 355         u8 d;
 356         struct transaction t = {.command = ACPI_EC_COMMAND_READ,
 357                                 .wdata = &address, .rdata = &d,
 358                                 .wlen = 1, .rlen = 1};
 359
 360         result = acpi_ec_transaction(ec, &t);
 361         *data = d;
 362         return result;
 363 }
 364
 365 static int acpi_ec_write(struct acpi_ec *ec, u8 address, u8 data)
 366 {
 367         u8 wdata[2] = { address, data };
 368         struct transaction t = {.command = ACPI_EC_COMMAND_WRITE,
 369                                 .wdata = wdata, .rdata = NULL,
 370                                 .wlen = 2, .rlen = 0};
 371
 372         return acpi_ec_transaction(ec, &t);
 373 }
 374
 375 /*
 376  * Externally callable EC access functions. For now, assume 1 EC only
 377  */
 378 int ec_burst_enable(void)
 379 {
 380         if (!first_ec)
 381                 return -ENODEV;
 382         return acpi_ec_burst_enable(first_ec);
 383 }
 384
 385 EXPORT_SYMBOL(ec_burst_enable);
 386
 387 int ec_burst_disable(void)
 388 {
 389         if (!first_ec)
 390                 return -ENODEV;
 391         return acpi_ec_burst_disable(first_ec);
 392 }
 393
 394 EXPORT_SYMBOL(ec_burst_disable);
 395
 396 int ec_read(u8 addr, u8 * val)
 397 {
 398         int err;
 399         u8 temp_data;
 400
 401         if (!first_ec)
 402                 return -ENODEV;
 403
 404         err = acpi_ec_read(first_ec, addr, &temp_data);
 405
 406         if (!err) {
 407                 *val = temp_data;
 408                 return 0;
 409         } else
 410                 return err;
 411 }
 412
 413 EXPORT_SYMBOL(ec_read);
 414
 415 int ec_write(u8 addr, u8 val)
 416 {
 417         int err;
 418
 419         if (!first_ec)
 420                 return -ENODEV;
 421
 422         err = acpi_ec_write(first_ec, addr, val);
 423
 424         return err;
 425 }
 426
 427 EXPORT_SYMBOL(ec_write);
 428
 429 int ec_transaction(u8 command,
 430                    const u8 * wdata, unsigned wdata_len,
 431                    u8 * rdata, unsigned rdata_len,
 432                    int force_poll)
 433 {
 434         struct transaction t = {.command = command,
 435                                 .wdata = wdata, .rdata = rdata,
 436                                 .wlen = wdata_len, .rlen = rdata_len};
 437         if (!first_ec)
 438                 return -ENODEV;
 439
 440         return acpi_ec_transaction(first_ec, &t);
 441 }
 442
 443 EXPORT_SYMBOL(ec_transaction);
 444
 445 static int acpi_ec_query(struct acpi_ec *ec, u8 * data)
 446 {
 447         int result;
 448         u8 d;
 449         struct transaction t = {.command = ACPI_EC_COMMAND_QUERY,
 450                                 .wdata = NULL, .rdata = &d,
 451                                 .wlen = 0, .rlen = 1};
 452         if (!ec || !data)
 453                 return -EINVAL;
 454
 455         /*
 456          * Query the EC to find out which _Qxx method we need to evaluate.
 457          * Note that successful completion of the query causes the ACPI_EC_SCI
 458          * bit to be cleared (and thus clearing the interrupt source).
 459          */
 460
 461         result = acpi_ec_transaction(ec, &t);
 462         if (result)
 463                 return result;
 464
 465         if (!d)
 466                 return -ENODATA;
 467
 468         *data = d;
 469         return 0;
 470 }
 471
 472 /* --------------------------------------------------------------------------
 473                                 Event Management
 474    -------------------------------------------------------------------------- */
 475 int acpi_ec_add_query_handler(struct acpi_ec *ec, u8 query_bit,
 476                               acpi_handle handle, acpi_ec_query_func func,
 477                               void *data)
 478 {
 479         struct acpi_ec_query_handler *handler =
 480             kzalloc(sizeof(struct acpi_ec_query_handler), GFP_KERNEL);
 481         if (!handler)
 482                 return -ENOMEM;
 483
 484         handler->query_bit = query_bit;
 485         handler->handle = handle;
 486         handler->func = func;
 487         handler->data = data;
 488         mutex_lock(&ec->lock);
 489         list_add(&handler->node, &ec->list);
 490         mutex_unlock(&ec->lock);
 491         return 0;
 492 }
 493
 494 EXPORT_SYMBOL_GPL(acpi_ec_add_query_handler);
 495
 496 void acpi_ec_remove_query_handler(struct acpi_ec *ec, u8 query_bit)
 497 {
 498         struct acpi_ec_query_handler *handler, *tmp;
 499         mutex_lock(&ec->lock);
 500         list_for_each_entry_safe(handler, tmp, &ec->list, node) {
 501                 if (query_bit == handler->query_bit) {
 502                         list_del(&handler->node);
 503                         kfree(handler);
 504                 }
 505         }
 506         mutex_unlock(&ec->lock);
 507 }
 508
 509 EXPORT_SYMBOL_GPL(acpi_ec_remove_query_handler);
 510
 511 static void acpi_ec_gpe_query(void *ec_cxt)
 512 {
 513         struct acpi_ec *ec = ec_cxt;
 514         u8 value = 0;
 515         struct acpi_ec_query_handler *handler, copy;
 516
 517         if (!ec || acpi_ec_query(ec, &value))
 518                 return;
 519         mutex_lock(&ec->lock);
 520         list_for_each_entry(handler, &ec->list, node) {
 521                 if (value == handler->query_bit) {
 522                         /* have custom handler for this bit */
 523                         memcpy(&copy, handler, sizeof(copy));
 524                         mutex_unlock(&ec->lock);
 525                         if (copy.func) {
 526                                 copy.func(copy.data);
 527                         } else if (copy.handle) {
 528                                 acpi_evaluate_object(copy.handle, NULL, NULL, NULL);
 529                         }
 530                         return;
 531                 }
 532         }
 533         mutex_unlock(&ec->lock);
 534 }
 535
 536 static u32 acpi_ec_gpe_handler(void *data)
 537 {
 538         struct acpi_ec *ec = data;
 539         u8 status;
 540
 541         pr_debug(PREFIX "~~~> interrupt\n");
 542         status = acpi_ec_read_status(ec);
 543
 544         advance_transaction(ec, status);
 545         if (ec_transaction_done(ec) && (status & ACPI_EC_FLAG_IBF) == 0)
 546                 wake_up(&ec->wait);
 547         ec_check_sci(ec, status);
 548         return ACPI_INTERRUPT_HANDLED;
 549 }
 550
 551 /* --------------------------------------------------------------------------
 552                              Address Space Management
 553    -------------------------------------------------------------------------- */
 554
 555 static acpi_status
 556 acpi_ec_space_handler(u32 function, acpi_physical_address address,
 557                       u32 bits, acpi_integer *value,
 558                       void *handler_context, void *region_context)
 559 {
 560         struct acpi_ec *ec = handler_context;
 561         int result = 0, i;
 562         u8 temp = 0;
 563
 564         if ((address > 0xFF) || !value || !handler_context)
 565                 return AE_BAD_PARAMETER;
 566
 567         if (function != ACPI_READ && function != ACPI_WRITE)
 568                 return AE_BAD_PARAMETER;
 569
 570         if (bits != 8 && acpi_strict)
 571                 return AE_BAD_PARAMETER;
 572
 573         if (EC_FLAGS_MSI)
 574                 acpi_ec_burst_enable(ec);
 575
 576         if (function == ACPI_READ) {
 577                 result = acpi_ec_read(ec, address, &temp);
 578                 *value = temp;
 579         } else {
 580                 temp = 0xff & (*value);
 581                 result = acpi_ec_write(ec, address, temp);
 582         }
 583
 584         for (i = 8; unlikely(bits - i > 0); i += 8) {
 585                 ++address;
 586                 if (function == ACPI_READ) {
 587                         result = acpi_ec_read(ec, address, &temp);
 588                         (*value) |= ((acpi_integer)temp) << i;
 589                 } else {
 590                         temp = 0xff & ((*value) >> i);
 591                         result = acpi_ec_write(ec, address, temp);
 592                 }
 593         }
 594
 595         if (EC_FLAGS_MSI)
 596                 acpi_ec_burst_disable(ec);
 597
 598         switch (result) {
 599         case -EINVAL:
 600                 return AE_BAD_PARAMETER;
 601                 break;
 602         case -ENODEV:
 603                 return AE_NOT_FOUND;
 604                 break;
 605         case -ETIME:
 606                 return AE_TIME;
 607                 break;
 608         default:
 609                 return AE_OK;
 610         }
 611 }
 612
 613 /* --------------------------------------------------------------------------
 614                               FS Interface (/proc)
 615    -------------------------------------------------------------------------- */
 616
 617 static struct proc_dir_entry *acpi_ec_dir;
 618
 619 static int acpi_ec_read_info(struct seq_file *seq, void *offset)
 620 {
 621         struct acpi_ec *ec = seq->private;
 622
 623         if (!ec)
 624                 goto end;
 625
 626         seq_printf(seq, "gpe:\t\t\t0x%02x\n", (u32) ec->gpe);
 627         seq_printf(seq, "ports:\t\t\t0x%02x, 0x%02x\n",
 628                    (unsigned)ec->command_addr, (unsigned)ec->data_addr);
 629         seq_printf(seq, "use global lock:\t%s\n",
 630                    ec->global_lock ? "yes" : "no");
 631       end:
 632         return 0;
 633 }
 634
 635 static int acpi_ec_info_open_fs(struct inode *inode, struct file *file)
 636 {
 637         return single_open(file, acpi_ec_read_info, PDE(inode)->data);
 638 }
 639
 640 static const struct file_operations acpi_ec_info_ops = {
 641         .open = acpi_ec_info_open_fs,
 642         .read = seq_read,
 643         .llseek = seq_lseek,
 644         .release = single_release,
 645         .owner = THIS_MODULE,
 646 };
 647
 648 static int acpi_ec_add_fs(struct acpi_device *device)
 649 {
 650         struct proc_dir_entry *entry = NULL;
 651
 652         if (!acpi_device_dir(device)) {
 653                 acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device),
 654                                                      acpi_ec_dir);
 655                 if (!acpi_device_dir(device))
 656                         return -ENODEV;
 657         }
 658
 659         entry = proc_create_data(ACPI_EC_FILE_INFO, S_IRUGO,
 660                                  acpi_device_dir(device),
 661                                  &acpi_ec_info_ops, acpi_driver_data(device));
 662         if (!entry)
 663                 return -ENODEV;
 664         return 0;
 665 }
 666
 667 static int acpi_ec_remove_fs(struct acpi_device *device)
 668 {
 669
 670         if (acpi_device_dir(device)) {
 671                 remove_proc_entry(ACPI_EC_FILE_INFO, acpi_device_dir(device));
 672                 remove_proc_entry(acpi_device_bid(device), acpi_ec_dir);
 673                 acpi_device_dir(device) = NULL;
 674         }
 675
 676         return 0;
 677 }
 678
 679 /* --------------------------------------------------------------------------
 680                                Driver Interface
 681    -------------------------------------------------------------------------- */
 682 static acpi_status
 683 ec_parse_io_ports(struct acpi_resource *resource, void *context);
 684
 685 static struct acpi_ec *make_acpi_ec(void)
 686 {
 687         struct acpi_ec *ec = kzalloc(sizeof(struct acpi_ec), GFP_KERNEL);
 688         if (!ec)
 689                 return NULL;
 690         ec->flags = 1 << EC_FLAGS_QUERY_PENDING;
 691         mutex_init(&ec->lock);
 692         init_waitqueue_head(&ec->wait);
 693         INIT_LIST_HEAD(&ec->list);
 694         spin_lock_init(&ec->curr_lock);
 695         return ec;
 696 }
 697
 698 static acpi_status
 699 acpi_ec_register_query_methods(acpi_handle handle, u32 level,
 700                                void *context, void **return_value)
 701 {
 702         char node_name[5];
 703         struct acpi_buffer buffer = { sizeof(node_name), node_name };
 704         struct acpi_ec *ec = context;
 705         int value = 0;
 706         acpi_status status;
 707
 708         status = acpi_get_name(handle, ACPI_SINGLE_NAME, &buffer);
 709
 710         if (ACPI_SUCCESS(status) && sscanf(node_name, "_Q%x", &value) == 1) {
 711                 acpi_ec_add_query_handler(ec, value, handle, NULL, NULL);
 712         }
 713         return AE_OK;
 714 }
 715
 716 static acpi_status
 717 ec_parse_device(acpi_handle handle, u32 Level, void *context, void **retval)
 718 {
 719         acpi_status status;
 720         unsigned long long tmp = 0;
 721
 722         struct acpi_ec *ec = context;
 723
 724         /* clear addr values, ec_parse_io_ports depend on it */
 725         ec->command_addr = ec->data_addr = 0;
 726
 727         status = acpi_walk_resources(handle, METHOD_NAME__CRS,
 728                                      ec_parse_io_ports, ec);
 729         if (ACPI_FAILURE(status))
 730                 return status;
 731
 732         /* Get GPE bit assignment (EC events). */
 733         /* TODO: Add support for _GPE returning a package */
 734         status = acpi_evaluate_integer(handle, "_GPE", NULL, &tmp);
 735         if (ACPI_FAILURE(status))
 736                 return status;
 737         ec->gpe = tmp;
 738         /* Use the global lock for all EC transactions? */
 739         tmp = 0;
 740         acpi_evaluate_integer(handle, "_GLK", NULL, &tmp);
 741         ec->global_lock = tmp;
 742         ec->handle = handle;
 743         return AE_CTRL_TERMINATE;
 744 }
 745
 746 static int ec_install_handlers(struct acpi_ec *ec)
 747 {
 748         acpi_status status;
 749         if (test_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags))
 750                 return 0;
 751         status = acpi_install_gpe_handler(NULL, ec->gpe,
 752                                   ACPI_GPE_EDGE_TRIGGERED,
 753                                   &acpi_ec_gpe_handler, ec);
 754         if (ACPI_FAILURE(status))
 755                 return -ENODEV;
 756         acpi_set_gpe_type(NULL, ec->gpe, ACPI_GPE_TYPE_RUNTIME);
 757         acpi_enable_gpe(NULL, ec->gpe);
 758         status = acpi_install_address_space_handler(ec->handle,
 759                                                     ACPI_ADR_SPACE_EC,
 760                                                     &acpi_ec_space_handler,
 761                                                     NULL, ec);
 762         if (ACPI_FAILURE(status)) {
 763                 if (status == AE_NOT_FOUND) {
 764                         /*
 765                          * Maybe OS fails in evaluating the _REG object.
 766                          * The AE_NOT_FOUND error will be ignored and OS
 767                          * continue to initialize EC.
 768                          */
 769                         printk(KERN_ERR "Fail in evaluating the _REG object"
 770                                 " of EC device. Broken bios is suspected.\n");
 771                 } else {
 772                         acpi_remove_gpe_handler(NULL, ec->gpe,
 773                                 &acpi_ec_gpe_handler);
 774                         return -ENODEV;
 775                 }
 776         }
 777
 778         set_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags);
 779         return 0;
 780 }
 781
 782 static void ec_remove_handlers(struct acpi_ec *ec)
 783 {
 784         if (ACPI_FAILURE(acpi_remove_address_space_handler(ec->handle,
 785                                 ACPI_ADR_SPACE_EC, &acpi_ec_space_handler)))
 786                 pr_err(PREFIX "failed to remove space handler\n");
 787         if (ACPI_FAILURE(acpi_remove_gpe_handler(NULL, ec->gpe,
 788                                 &acpi_ec_gpe_handler)))
 789                 pr_err(PREFIX "failed to remove gpe handler\n");
 790         clear_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags);
 791 }
 792
 793 static int acpi_ec_add(struct acpi_device *device)
 794 {
 795         struct acpi_ec *ec = NULL;
 796         int ret;
 797
 798         strcpy(acpi_device_name(device), ACPI_EC_DEVICE_NAME);
 799         strcpy(acpi_device_class(device), ACPI_EC_CLASS);
 800
 801         /* Check for boot EC */
 802         if (boot_ec &&
 803             (boot_ec->handle == device->handle ||
 804              boot_ec->handle == ACPI_ROOT_OBJECT)) {
 805                 ec = boot_ec;
 806                 boot_ec = NULL;
 807         } else {
 808                 ec = make_acpi_ec();
 809                 if (!ec)
 810                         return -ENOMEM;
 811         }
 812         if (ec_parse_device(device->handle, 0, ec, NULL) !=
 813                 AE_CTRL_TERMINATE) {
 814                         kfree(ec);
 815                         return -EINVAL;
 816         }
 817
 818         ec->handle = device->handle;
 819
 820         /* Find and register all query methods */
 821         acpi_walk_namespace(ACPI_TYPE_METHOD, ec->handle, 1,
 822                             acpi_ec_register_query_methods, ec, NULL);
 823
 824         if (!first_ec)
 825                 first_ec = ec;
 826         device->driver_data = ec;
 827         acpi_ec_add_fs(device);
 828         pr_info(PREFIX "GPE = 0x%lx, I/O: command/status = 0x%lx, data = 0x%lx\n",
 829                           ec->gpe, ec->command_addr, ec->data_addr);
 830
 831         ret = ec_install_handlers(ec);
 832
 833         /* EC is fully operational, allow queries */
 834         clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags);
 835         return ret;
 836 }
 837
 838 static int acpi_ec_remove(struct acpi_device *device, int type)
 839 {
 840         struct acpi_ec *ec;
 841         struct acpi_ec_query_handler *handler, *tmp;
 842
 843         if (!device)
 844                 return -EINVAL;
 845
 846         ec = acpi_driver_data(device);
 847         ec_remove_handlers(ec);
 848         mutex_lock(&ec->lock);
 849         list_for_each_entry_safe(handler, tmp, &ec->list, node) {
 850                 list_del(&handler->node);
 851                 kfree(handler);
 852         }
 853         mutex_unlock(&ec->lock);
 854         acpi_ec_remove_fs(device);
 855         device->driver_data = NULL;
 856         if (ec == first_ec)
 857                 first_ec = NULL;
 858         kfree(ec);
 859         return 0;
 860 }
 861
 862 static acpi_status
 863 ec_parse_io_ports(struct acpi_resource *resource, void *context)
 864 {
 865         struct acpi_ec *ec = context;
 866
 867         if (resource->type != ACPI_RESOURCE_TYPE_IO)
 868                 return AE_OK;
 869
 870         /*
 871          * The first address region returned is the data port, and
 872          * the second address region returned is the status/command
 873          * port.
 874          */
 875         if (ec->data_addr == 0)
 876                 ec->data_addr = resource->data.io.minimum;
 877         else if (ec->command_addr == 0)
 878                 ec->command_addr = resource->data.io.minimum;
 879         else
 880                 return AE_CTRL_TERMINATE;
 881
 882         return AE_OK;
 883 }
 884
 885 int __init acpi_boot_ec_enable(void)
 886 {
 887         if (!boot_ec || test_bit(EC_FLAGS_HANDLERS_INSTALLED, &boot_ec->flags))
 888                 return 0;
 889         if (!ec_install_handlers(boot_ec)) {
 890                 first_ec = boot_ec;
 891                 return 0;
 892         }
 893         return -EFAULT;
 894 }
 895
 896 static const struct acpi_device_id ec_device_ids[] = {
 897         {"PNP0C09", 0},
 898         {"", 0},
 899 };
 900
 901 int __init acpi_ec_ecdt_probe(void)
 902 {
 903         acpi_status status;
 904         struct acpi_ec *saved_ec = NULL;
 905         struct acpi_table_ecdt *ecdt_ptr;
 906
 907         boot_ec = make_acpi_ec();
 908         if (!boot_ec)
 909                 return -ENOMEM;
 910         /*
 911          * Generate a boot ec context
 912          */
 913         if (dmi_name_in_vendors("Micro-Star") ||
 914             dmi_name_in_vendors("Notebook")) {
 915                 pr_info(PREFIX "Enabling special treatment for EC from MSI.\n");
 916                 EC_FLAGS_MSI = 1;
 917         }
 918         status = acpi_get_table(ACPI_SIG_ECDT, 1,
 919                                 (struct acpi_table_header **)&ecdt_ptr);
 920         if (ACPI_SUCCESS(status)) {
 921                 pr_info(PREFIX "EC description table is found, configuring boot EC\n");
 922                 boot_ec->command_addr = ecdt_ptr->control.address;
 923                 boot_ec->data_addr = ecdt_ptr->data.address;
 924                 boot_ec->gpe = ecdt_ptr->gpe;
 925                 boot_ec->handle = ACPI_ROOT_OBJECT;
 926                 acpi_get_handle(ACPI_ROOT_OBJECT, ecdt_ptr->id, &boot_ec->handle);
 927                 /* Don't trust ECDT, which comes from ASUSTek */
 928                 if (!dmi_name_in_vendors("ASUS") && EC_FLAGS_MSI == 0)
 929                         goto install;
 930                 saved_ec = kmalloc(sizeof(struct acpi_ec), GFP_KERNEL);
 931                 if (!saved_ec)
 932                         return -ENOMEM;
 933                 memcpy(saved_ec, boot_ec, sizeof(struct acpi_ec));
 934         /* fall through */
 935         }
 936         /* This workaround is needed only on some broken machines,
 937          * which require early EC, but fail to provide ECDT */
 938         printk(KERN_DEBUG PREFIX "Look up EC in DSDT\n");
 939         status = acpi_get_devices(ec_device_ids[0].id, ec_parse_device,
 940                                         boot_ec, NULL);
 941         /* Check that acpi_get_devices actually find something */
 942         if (ACPI_FAILURE(status) || !boot_ec->handle)
 943                 goto error;
 944         if (saved_ec) {
 945                 /* try to find good ECDT from ASUSTek */
 946                 if (saved_ec->command_addr != boot_ec->command_addr ||
 947                     saved_ec->data_addr != boot_ec->data_addr ||
 948                     saved_ec->gpe != boot_ec->gpe ||
 949                     saved_ec->handle != boot_ec->handle)
 950                         pr_info(PREFIX "ASUSTek keeps feeding us with broken "
 951                         "ECDT tables, which are very hard to workaround. "
 952                         "Trying to use DSDT EC info instead. Please send "
 953                         "output of acpidump to linux-acpi@vger.kernel.org\n");
 954                 kfree(saved_ec);
 955                 saved_ec = NULL;
 956         } else {
 957                 /* We really need to limit this workaround, the only ASUS,
 958                 * which needs it, has fake EC._INI method, so use it as flag.
 959                 * Keep boot_ec struct as it will be needed soon.
 960                 */
 961                 acpi_handle dummy;
 962                 if (!dmi_name_in_vendors("ASUS") ||
 963                     ACPI_FAILURE(acpi_get_handle(boot_ec->handle, "_INI",
 964                                                         &dummy)))
 965                         return -ENODEV;
 966         }
 967 install:
 968         if (!ec_install_handlers(boot_ec)) {
 969                 first_ec = boot_ec;
 970                 return 0;
 971         }
 972 error:
 973         kfree(boot_ec);
 974         boot_ec = NULL;
 975         return -ENODEV;
 976 }
 977
 978 static int acpi_ec_suspend(struct acpi_device *device, pm_message_t state)
 979 {
 980         struct acpi_ec *ec = acpi_driver_data(device);
 981         /* Stop using GPE */
 982         acpi_disable_gpe(NULL, ec->gpe);
 983         return 0;
 984 }
 985
 986 static int acpi_ec_resume(struct acpi_device *device)
 987 {
 988         struct acpi_ec *ec = acpi_driver_data(device);
 989         /* Enable use of GPE back */
 990         acpi_enable_gpe(NULL, ec->gpe);
 991         return 0;
 992 }
 993
 994 static struct acpi_driver acpi_ec_driver = {
 995         .name = "ec",
 996         .class = ACPI_EC_CLASS,
 997         .ids = ec_device_ids,
 998         .ops = {
 999                 .add = acpi_ec_add,
1000                 .remove = acpi_ec_remove,
1001                 .suspend = acpi_ec_suspend,
1002                 .resume = acpi_ec_resume,
1003                 },
1004 };
1005
1006 int __init acpi_ec_init(void)
1007 {
1008         int result = 0;
1009
1010         acpi_ec_dir = proc_mkdir(ACPI_EC_CLASS, acpi_root_dir);
1011         if (!acpi_ec_dir)
1012                 return -ENODEV;
1013
1014         /* Now register the driver for the EC */
1015         result = acpi_bus_register_driver(&acpi_ec_driver);
1016         if (result < 0) {
1017                 remove_proc_entry(ACPI_EC_CLASS, acpi_root_dir);
1018                 return -ENODEV;
1019         }
1020
1021         return result;
1022 }
1023
1024 /* EC driver currently not unloadable */
1025 #if 0
1026 static void __exit acpi_ec_exit(void)
1027 {
1028
1029         acpi_bus_unregister_driver(&acpi_ec_driver);
1030
1031         remove_proc_entry(ACPI_EC_CLASS, acpi_root_dir);
1032
1033         return;
1034 }
1035 #endif  /* 0 */