drivers/acpi/ec.c

   1 /*
   2  *  ec.c - ACPI Embedded Controller Driver (v2.1)
   3  *
   4  *  Copyright (C) 2006-2008 Alexey Starikovskiy <astarikovskiy@suse.de>
   5  *  Copyright (C) 2006 Denis Sadykov <denis.m.sadykov@intel.com>
   6  *  Copyright (C) 2004 Luming Yu <luming.yu@intel.com>
   7  *  Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
   8  *  Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
   9  *
  10  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  11  *
  12  *  This program is free software; you can redistribute it and/or modify
  13  *  it under the terms of the GNU General Public License as published by
  14  *  the Free Software Foundation; either version 2 of the License, or (at
  15  *  your option) any later version.
  16  *
  17  *  This program is distributed in the hope that it will be useful, but
  18  *  WITHOUT ANY WARRANTY; without even the implied warranty of
  19  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  20  *  General Public License for more details.
  21  *
  22  *  You should have received a copy of the GNU General Public License along
  23  *  with this program; if not, write to the Free Software Foundation, Inc.,
  24  *  59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
  25  *
  26  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  27  */
  28
  29 /* Uncomment next line to get verbose printout */
  30 /* #define DEBUG */
  31
  32 #include <linux/kernel.h>
  33 #include <linux/module.h>
  34 #include <linux/init.h>
  35 #include <linux/types.h>
  36 #include <linux/delay.h>
  37 #include <linux/interrupt.h>
  38 #include <linux/list.h>
  39 #include <linux/spinlock.h>
  40 #include <linux/slab.h>
  41 #include <asm/io.h>
  42 #include <acpi/acpi_bus.h>
  43 #include <acpi/acpi_drivers.h>
  44 #include <linux/dmi.h>
  45
  46 #include "internal.h"
  47
  48 #define ACPI_EC_CLASS                   "embedded_controller"
  49 #define ACPI_EC_DEVICE_NAME             "Embedded Controller"
  50 #define ACPI_EC_FILE_INFO               "info"
  51
  52 #undef PREFIX
  53 #define PREFIX                          "ACPI: EC: "
  54
  55 /* EC status register */
  56 #define ACPI_EC_FLAG_OBF        0x01    /* Output buffer full */
  57 #define ACPI_EC_FLAG_IBF        0x02    /* Input buffer full */
  58 #define ACPI_EC_FLAG_BURST      0x10    /* burst mode */
  59 #define ACPI_EC_FLAG_SCI        0x20    /* EC-SCI occurred */
  60
  61 /* EC commands */
  62 enum ec_command {
  63         ACPI_EC_COMMAND_READ = 0x80,
  64         ACPI_EC_COMMAND_WRITE = 0x81,
  65         ACPI_EC_BURST_ENABLE = 0x82,
  66         ACPI_EC_BURST_DISABLE = 0x83,
  67         ACPI_EC_COMMAND_QUERY = 0x84,
  68 };
  69
  70 #define ACPI_EC_DELAY           500     /* Wait 500ms max. during EC ops */
  71 #define ACPI_EC_UDELAY_GLK      1000    /* Wait 1ms max. to get global lock */
  72 #define ACPI_EC_MSI_UDELAY      550     /* Wait 550us for MSI EC */
  73
  74 enum {
  75         EC_FLAGS_QUERY_PENDING,         /* Query is pending */
  76         EC_FLAGS_GPE_STORM,             /* GPE storm detected */
  77         EC_FLAGS_HANDLERS_INSTALLED,    /* Handlers for GPE and
  78                                          * OpReg are installed */
  79         EC_FLAGS_BLOCKED,               /* Transactions are blocked */
  80 };
  81
  82 /* ec.c is compiled in acpi namespace so this shows up as acpi.ec_delay param */
  83 static unsigned int ec_delay __read_mostly = ACPI_EC_DELAY;
  84 module_param(ec_delay, uint, 0644);
  85 MODULE_PARM_DESC(ec_delay, "Timeout(ms) waited until an EC command completes");
  86
  87 /*
  88  * If the number of false interrupts per one transaction exceeds
  89  * this threshold, will think there is a GPE storm happened and
  90  * will disable the GPE for normal transaction.
  91  */
  92 static unsigned int ec_storm_threshold  __read_mostly = 8;
  93 module_param(ec_storm_threshold, uint, 0644);
  94 MODULE_PARM_DESC(ec_storm_threshold, "Maxim false GPE numbers not considered as GPE storm");
  95
  96 /* If we find an EC via the ECDT, we need to keep a ptr to its context */
  97 /* External interfaces use first EC only, so remember */
  98 typedef int (*acpi_ec_query_func) (void *data);
  99
 100 struct acpi_ec_query_handler {
 101         struct list_head node;
 102         acpi_ec_query_func func;
 103         acpi_handle handle;
 104         void *data;
 105         u8 query_bit;
 106 };
 107
 108 struct transaction {
 109         const u8 *wdata;
 110         u8 *rdata;
 111         unsigned short irq_count;
 112         u8 command;
 113         u8 wi;
 114         u8 ri;
 115         u8 wlen;
 116         u8 rlen;
 117         bool done;
 118 };
 119
 120 struct acpi_ec *boot_ec, *first_ec;
 121 EXPORT_SYMBOL(first_ec);
 122
 123 static int EC_FLAGS_MSI; /* Out-of-spec MSI controller */
 124 static int EC_FLAGS_VALIDATE_ECDT; /* ASUStec ECDTs need to be validated */
 125 static int EC_FLAGS_SKIP_DSDT_SCAN; /* Not all BIOS survive early DSDT scan */
 126
 127 /* --------------------------------------------------------------------------
 128                              Transaction Management
 129    -------------------------------------------------------------------------- */
 130
 131 static inline u8 acpi_ec_read_status(struct acpi_ec *ec)
 132 {
 133         u8 x = inb(ec->command_addr);
 134         pr_debug(PREFIX "---> status = 0x%2.2x\n", x);
 135         return x;
 136 }
 137
 138 static inline u8 acpi_ec_read_data(struct acpi_ec *ec)
 139 {
 140         u8 x = inb(ec->data_addr);
 141         pr_debug(PREFIX "---> data = 0x%2.2x\n", x);
 142         return x;
 143 }
 144
 145 static inline void acpi_ec_write_cmd(struct acpi_ec *ec, u8 command)
 146 {
 147         pr_debug(PREFIX "<--- command = 0x%2.2x\n", command);
 148         outb(command, ec->command_addr);
 149 }
 150
 151 static inline void acpi_ec_write_data(struct acpi_ec *ec, u8 data)
 152 {
 153         pr_debug(PREFIX "<--- data = 0x%2.2x\n", data);
 154         outb(data, ec->data_addr);
 155 }
 156
 157 static int ec_transaction_done(struct acpi_ec *ec)
 158 {
 159         unsigned long flags;
 160         int ret = 0;
 161         spin_lock_irqsave(&ec->lock, flags);
 162         if (!ec->curr || ec->curr->done)
 163                 ret = 1;
 164         spin_unlock_irqrestore(&ec->lock, flags);
 165         return ret;
 166 }
 167
 168 static void start_transaction(struct acpi_ec *ec)
 169 {
 170         ec->curr->irq_count = ec->curr->wi = ec->curr->ri = 0;
 171         ec->curr->done = false;
 172         acpi_ec_write_cmd(ec, ec->curr->command);
 173 }
 174
 175 static void advance_transaction(struct acpi_ec *ec, u8 status)
 176 {
 177         unsigned long flags;
 178         struct transaction *t = ec->curr;
 179
 180         spin_lock_irqsave(&ec->lock, flags);
 181         if (!t)
 182                 goto unlock;
 183         if (t->wlen > t->wi) {
 184                 if ((status & ACPI_EC_FLAG_IBF) == 0)
 185                         acpi_ec_write_data(ec,
 186                                 t->wdata[t->wi++]);
 187                 else
 188                         goto err;
 189         } else if (t->rlen > t->ri) {
 190                 if ((status & ACPI_EC_FLAG_OBF) == 1) {
 191                         t->rdata[t->ri++] = acpi_ec_read_data(ec);
 192                         if (t->rlen == t->ri)
 193                                 t->done = true;
 194                 } else
 195                         goto err;
 196         } else if (t->wlen == t->wi &&
 197                    (status & ACPI_EC_FLAG_IBF) == 0)
 198                 t->done = true;
 199         goto unlock;
 200 err:
 201         /*
 202          * If SCI bit is set, then don't think it's a false IRQ
 203          * otherwise will take a not handled IRQ as a false one.
 204          */
 205         if (in_interrupt() && !(status & ACPI_EC_FLAG_SCI))
 206                 ++t->irq_count;
 207
 208 unlock:
 209         spin_unlock_irqrestore(&ec->lock, flags);
 210 }
 211
 212 static int acpi_ec_sync_query(struct acpi_ec *ec);
 213
 214 static int ec_check_sci_sync(struct acpi_ec *ec, u8 state)
 215 {
 216         if (state & ACPI_EC_FLAG_SCI) {
 217                 if (!test_and_set_bit(EC_FLAGS_QUERY_PENDING, &ec->flags))
 218                         return acpi_ec_sync_query(ec);
 219         }
 220         return 0;
 221 }
 222
 223 static int ec_poll(struct acpi_ec *ec)
 224 {
 225         unsigned long flags;
 226         int repeat = 5; /* number of command restarts */
 227         while (repeat--) {
 228                 unsigned long delay = jiffies +
 229                         msecs_to_jiffies(ec_delay);
 230                 do {
 231                         /* don't sleep with disabled interrupts */
 232                         if (EC_FLAGS_MSI || irqs_disabled()) {
 233                                 udelay(ACPI_EC_MSI_UDELAY);
 234                                 if (ec_transaction_done(ec))
 235                                         return 0;
 236                         } else {
 237                                 if (wait_event_timeout(ec->wait,
 238                                                 ec_transaction_done(ec),
 239                                                 msecs_to_jiffies(1)))
 240                                         return 0;
 241                         }
 242                         advance_transaction(ec, acpi_ec_read_status(ec));
 243                 } while (time_before(jiffies, delay));
 244                 pr_debug(PREFIX "controller reset, restart transaction\n");
 245                 spin_lock_irqsave(&ec->lock, flags);
 246                 start_transaction(ec);
 247                 spin_unlock_irqrestore(&ec->lock, flags);
 248         }
 249         return -ETIME;
 250 }
 251
 252 static int acpi_ec_transaction_unlocked(struct acpi_ec *ec,
 253                                         struct transaction *t)
 254 {
 255         unsigned long tmp;
 256         int ret = 0;
 257         if (EC_FLAGS_MSI)
 258                 udelay(ACPI_EC_MSI_UDELAY);
 259         /* start transaction */
 260         spin_lock_irqsave(&ec->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->lock, tmp);
 267         ret = ec_poll(ec);
 268         spin_lock_irqsave(&ec->lock, tmp);
 269         ec->curr = NULL;
 270         spin_unlock_irqrestore(&ec->lock, tmp);
 271         return ret;
 272 }
 273
 274 static int ec_check_ibf0(struct acpi_ec *ec)
 275 {
 276         u8 status = acpi_ec_read_status(ec);
 277         return (status & ACPI_EC_FLAG_IBF) == 0;
 278 }
 279
 280 static int ec_wait_ibf0(struct acpi_ec *ec)
 281 {
 282         unsigned long delay = jiffies + msecs_to_jiffies(ec_delay);
 283         /* interrupt wait manually if GPE mode is not active */
 284         while (time_before(jiffies, delay))
 285                 if (wait_event_timeout(ec->wait, ec_check_ibf0(ec),
 286                                         msecs_to_jiffies(1)))
 287                         return 0;
 288         return -ETIME;
 289 }
 290
 291 static int acpi_ec_transaction(struct acpi_ec *ec, struct transaction *t)
 292 {
 293         int status;
 294         u32 glk;
 295         if (!ec || (!t) || (t->wlen && !t->wdata) || (t->rlen && !t->rdata))
 296                 return -EINVAL;
 297         if (t->rdata)
 298                 memset(t->rdata, 0, t->rlen);
 299         mutex_lock(&ec->mutex);
 300         if (test_bit(EC_FLAGS_BLOCKED, &ec->flags)) {
 301                 status = -EINVAL;
 302                 goto unlock;
 303         }
 304         if (ec->global_lock) {
 305                 status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk);
 306                 if (ACPI_FAILURE(status)) {
 307                         status = -ENODEV;
 308                         goto unlock;
 309                 }
 310         }
 311         if (ec_wait_ibf0(ec)) {
 312                 pr_err(PREFIX "input buffer is not empty, "
 313                                 "aborting transaction\n");
 314                 status = -ETIME;
 315                 goto end;
 316         }
 317         pr_debug(PREFIX "transaction start (cmd=0x%02x, addr=0x%02x)\n",
 318                         t->command, t->wdata ? t->wdata[0] : 0);
 319         /* disable GPE during transaction if storm is detected */
 320         if (test_bit(EC_FLAGS_GPE_STORM, &ec->flags)) {
 321                 /* It has to be disabled, so that it doesn't trigger. */
 322                 acpi_disable_gpe(NULL, ec->gpe);
 323         }
 324
 325         status = acpi_ec_transaction_unlocked(ec, t);
 326
 327         /* check if we received SCI during transaction */
 328         ec_check_sci_sync(ec, acpi_ec_read_status(ec));
 329         if (test_bit(EC_FLAGS_GPE_STORM, &ec->flags)) {
 330                 msleep(1);
 331                 /* It is safe to enable the GPE outside of the transaction. */
 332                 acpi_enable_gpe(NULL, ec->gpe);
 333         } else if (t->irq_count > ec_storm_threshold) {
 334                 pr_info(PREFIX "GPE storm detected(%d GPEs), "
 335                         "transactions will use polling mode\n",
 336                         t->irq_count);
 337                 set_bit(EC_FLAGS_GPE_STORM, &ec->flags);
 338         }
 339         pr_debug(PREFIX "transaction end\n");
 340 end:
 341         if (ec->global_lock)
 342                 acpi_release_global_lock(glk);
 343 unlock:
 344         mutex_unlock(&ec->mutex);
 345         return status;
 346 }
 347
 348 static int acpi_ec_burst_enable(struct acpi_ec *ec)
 349 {
 350         u8 d;
 351         struct transaction t = {.command = ACPI_EC_BURST_ENABLE,
 352                                 .wdata = NULL, .rdata = &d,
 353                                 .wlen = 0, .rlen = 1};
 354
 355         return acpi_ec_transaction(ec, &t);
 356 }
 357
 358 static int acpi_ec_burst_disable(struct acpi_ec *ec)
 359 {
 360         struct transaction t = {.command = ACPI_EC_BURST_DISABLE,
 361                                 .wdata = NULL, .rdata = NULL,
 362                                 .wlen = 0, .rlen = 0};
 363
 364         return (acpi_ec_read_status(ec) & ACPI_EC_FLAG_BURST) ?
 365                                 acpi_ec_transaction(ec, &t) : 0;
 366 }
 367
 368 static int acpi_ec_read(struct acpi_ec *ec, u8 address, u8 * data)
 369 {
 370         int result;
 371         u8 d;
 372         struct transaction t = {.command = ACPI_EC_COMMAND_READ,
 373                                 .wdata = &address, .rdata = &d,
 374                                 .wlen = 1, .rlen = 1};
 375
 376         result = acpi_ec_transaction(ec, &t);
 377         *data = d;
 378         return result;
 379 }
 380
 381 static int acpi_ec_write(struct acpi_ec *ec, u8 address, u8 data)
 382 {
 383         u8 wdata[2] = { address, data };
 384         struct transaction t = {.command = ACPI_EC_COMMAND_WRITE,
 385                                 .wdata = wdata, .rdata = NULL,
 386                                 .wlen = 2, .rlen = 0};
 387
 388         return acpi_ec_transaction(ec, &t);
 389 }
 390
 391 /*
 392  * Externally callable EC access functions. For now, assume 1 EC only
 393  */
 394 int ec_burst_enable(void)
 395 {
 396         if (!first_ec)
 397                 return -ENODEV;
 398         return acpi_ec_burst_enable(first_ec);
 399 }
 400
 401 EXPORT_SYMBOL(ec_burst_enable);
 402
 403 int ec_burst_disable(void)
 404 {
 405         if (!first_ec)
 406                 return -ENODEV;
 407         return acpi_ec_burst_disable(first_ec);
 408 }
 409
 410 EXPORT_SYMBOL(ec_burst_disable);
 411
 412 int ec_read(u8 addr, u8 *val)
 413 {
 414         int err;
 415         u8 temp_data;
 416
 417         if (!first_ec)
 418                 return -ENODEV;
 419
 420         err = acpi_ec_read(first_ec, addr, &temp_data);
 421
 422         if (!err) {
 423                 *val = temp_data;
 424                 return 0;
 425         } else
 426                 return err;
 427 }
 428
 429 EXPORT_SYMBOL(ec_read);
 430
 431 int ec_write(u8 addr, u8 val)
 432 {
 433         int err;
 434
 435         if (!first_ec)
 436                 return -ENODEV;
 437
 438         err = acpi_ec_write(first_ec, addr, val);
 439
 440         return err;
 441 }
 442
 443 EXPORT_SYMBOL(ec_write);
 444
 445 int ec_transaction(u8 command,
 446                    const u8 * wdata, unsigned wdata_len,
 447                    u8 * rdata, unsigned rdata_len)
 448 {
 449         struct transaction t = {.command = command,
 450                                 .wdata = wdata, .rdata = rdata,
 451                                 .wlen = wdata_len, .rlen = rdata_len};
 452         if (!first_ec)
 453                 return -ENODEV;
 454
 455         return acpi_ec_transaction(first_ec, &t);
 456 }
 457
 458 EXPORT_SYMBOL(ec_transaction);
 459
 460 /* Get the handle to the EC device */
 461 acpi_handle ec_get_handle(void)
 462 {
 463         if (!first_ec)
 464                 return NULL;
 465         return first_ec->handle;
 466 }
 467
 468 EXPORT_SYMBOL(ec_get_handle);
 469
 470 void acpi_ec_block_transactions(void)
 471 {
 472         struct acpi_ec *ec = first_ec;
 473
 474         if (!ec)
 475                 return;
 476
 477         mutex_lock(&ec->mutex);
 478         /* Prevent transactions from being carried out */
 479         set_bit(EC_FLAGS_BLOCKED, &ec->flags);
 480         mutex_unlock(&ec->mutex);
 481 }
 482
 483 void acpi_ec_unblock_transactions(void)
 484 {
 485         struct acpi_ec *ec = first_ec;
 486
 487         if (!ec)
 488                 return;
 489
 490         mutex_lock(&ec->mutex);
 491         /* Allow transactions to be carried out again */
 492         clear_bit(EC_FLAGS_BLOCKED, &ec->flags);
 493         mutex_unlock(&ec->mutex);
 494 }
 495
 496 void acpi_ec_unblock_transactions_early(void)
 497 {
 498         /*
 499          * Allow transactions to happen again (this function is called from
 500          * atomic context during wakeup, so we don't need to acquire the mutex).
 501          */
 502         if (first_ec)
 503                 clear_bit(EC_FLAGS_BLOCKED, &first_ec->flags);
 504 }
 505
 506 static int acpi_ec_query_unlocked(struct acpi_ec *ec, u8 * data)
 507 {
 508         int result;
 509         u8 d;
 510         struct transaction t = {.command = ACPI_EC_COMMAND_QUERY,
 511                                 .wdata = NULL, .rdata = &d,
 512                                 .wlen = 0, .rlen = 1};
 513         if (!ec || !data)
 514                 return -EINVAL;
 515         /*
 516          * Query the EC to find out which _Qxx method we need to evaluate.
 517          * Note that successful completion of the query causes the ACPI_EC_SCI
 518          * bit to be cleared (and thus clearing the interrupt source).
 519          */
 520         result = acpi_ec_transaction_unlocked(ec, &t);
 521         if (result)
 522                 return result;
 523         if (!d)
 524                 return -ENODATA;
 525         *data = d;
 526         return 0;
 527 }
 528
 529 /* --------------------------------------------------------------------------
 530                                 Event Management
 531    -------------------------------------------------------------------------- */
 532 int acpi_ec_add_query_handler(struct acpi_ec *ec, u8 query_bit,
 533                               acpi_handle handle, acpi_ec_query_func func,
 534                               void *data)
 535 {
 536         struct acpi_ec_query_handler *handler =
 537             kzalloc(sizeof(struct acpi_ec_query_handler), GFP_KERNEL);
 538         if (!handler)
 539                 return -ENOMEM;
 540
 541         handler->query_bit = query_bit;
 542         handler->handle = handle;
 543         handler->func = func;
 544         handler->data = data;
 545         mutex_lock(&ec->mutex);
 546         list_add(&handler->node, &ec->list);
 547         mutex_unlock(&ec->mutex);
 548         return 0;
 549 }
 550
 551 EXPORT_SYMBOL_GPL(acpi_ec_add_query_handler);
 552
 553 void acpi_ec_remove_query_handler(struct acpi_ec *ec, u8 query_bit)
 554 {
 555         struct acpi_ec_query_handler *handler, *tmp;
 556         mutex_lock(&ec->mutex);
 557         list_for_each_entry_safe(handler, tmp, &ec->list, node) {
 558                 if (query_bit == handler->query_bit) {
 559                         list_del(&handler->node);
 560                         kfree(handler);
 561                 }
 562         }
 563         mutex_unlock(&ec->mutex);
 564 }
 565
 566 EXPORT_SYMBOL_GPL(acpi_ec_remove_query_handler);
 567
 568 static void acpi_ec_run(void *cxt)
 569 {
 570         struct acpi_ec_query_handler *handler = cxt;
 571         if (!handler)
 572                 return;
 573         pr_debug(PREFIX "start query execution\n");
 574         if (handler->func)
 575                 handler->func(handler->data);
 576         else if (handler->handle)
 577                 acpi_evaluate_object(handler->handle, NULL, NULL, NULL);
 578         pr_debug(PREFIX "stop query execution\n");
 579         kfree(handler);
 580 }
 581
 582 static int acpi_ec_sync_query(struct acpi_ec *ec)
 583 {
 584         u8 value = 0;
 585         int status;
 586         struct acpi_ec_query_handler *handler, *copy;
 587         if ((status = acpi_ec_query_unlocked(ec, &value)))
 588                 return status;
 589         list_for_each_entry(handler, &ec->list, node) {
 590                 if (value == handler->query_bit) {
 591                         /* have custom handler for this bit */
 592                         copy = kmalloc(sizeof(*handler), GFP_KERNEL);
 593                         if (!copy)
 594                                 return -ENOMEM;
 595                         memcpy(copy, handler, sizeof(*copy));
 596                         pr_debug(PREFIX "push query execution (0x%2x) on queue\n", value);
 597                         return acpi_os_execute((copy->func) ?
 598                                 OSL_NOTIFY_HANDLER : OSL_GPE_HANDLER,
 599                                 acpi_ec_run, copy);
 600                 }
 601         }
 602         return 0;
 603 }
 604
 605 static void acpi_ec_gpe_query(void *ec_cxt)
 606 {
 607         struct acpi_ec *ec = ec_cxt;
 608         if (!ec)
 609                 return;
 610         mutex_lock(&ec->mutex);
 611         acpi_ec_sync_query(ec);
 612         mutex_unlock(&ec->mutex);
 613 }
 614
 615 static int ec_check_sci(struct acpi_ec *ec, u8 state)
 616 {
 617         if (state & ACPI_EC_FLAG_SCI) {
 618                 if (!test_and_set_bit(EC_FLAGS_QUERY_PENDING, &ec->flags)) {
 619                         pr_debug(PREFIX "push gpe query to the queue\n");
 620                         return acpi_os_execute(OSL_NOTIFY_HANDLER,
 621                                 acpi_ec_gpe_query, ec);
 622                 }
 623         }
 624         return 0;
 625 }
 626
 627 static u32 acpi_ec_gpe_handler(acpi_handle gpe_device,
 628         u32 gpe_number, void *data)
 629 {
 630         struct acpi_ec *ec = data;
 631         u8 status = acpi_ec_read_status(ec);
 632
 633         pr_debug(PREFIX "~~~> interrupt, status:0x%02x\n", status);
 634
 635         advance_transaction(ec, status);
 636         if (ec_transaction_done(ec) &&
 637             (acpi_ec_read_status(ec) & ACPI_EC_FLAG_IBF) == 0) {
 638                 wake_up(&ec->wait);
 639                 ec_check_sci(ec, acpi_ec_read_status(ec));
 640         }
 641         return ACPI_INTERRUPT_HANDLED | ACPI_REENABLE_GPE;
 642 }
 643
 644 /* --------------------------------------------------------------------------
 645                              Address Space Management
 646    -------------------------------------------------------------------------- */
 647
 648 static acpi_status
 649 acpi_ec_space_handler(u32 function, acpi_physical_address address,
 650                       u32 bits, u64 *value64,
 651                       void *handler_context, void *region_context)
 652 {
 653         struct acpi_ec *ec = handler_context;
 654         int result = 0, i, bytes = bits / 8;
 655         u8 *value = (u8 *)value64;
 656
 657         if ((address > 0xFF) || !value || !handler_context)
 658                 return AE_BAD_PARAMETER;
 659
 660         if (function != ACPI_READ && function != ACPI_WRITE)
 661                 return AE_BAD_PARAMETER;
 662
 663         if (EC_FLAGS_MSI || bits > 8)
 664                 acpi_ec_burst_enable(ec);
 665
 666         for (i = 0; i < bytes; ++i, ++address, ++value)
 667                 result = (function == ACPI_READ) ?
 668                         acpi_ec_read(ec, address, value) :
 669                         acpi_ec_write(ec, address, *value);
 670
 671         if (EC_FLAGS_MSI || bits > 8)
 672                 acpi_ec_burst_disable(ec);
 673
 674         switch (result) {
 675         case -EINVAL:
 676                 return AE_BAD_PARAMETER;
 677                 break;
 678         case -ENODEV:
 679                 return AE_NOT_FOUND;
 680                 break;
 681         case -ETIME:
 682                 return AE_TIME;
 683                 break;
 684         default:
 685                 return AE_OK;
 686         }
 687 }
 688
 689 /* --------------------------------------------------------------------------
 690                                Driver Interface
 691    -------------------------------------------------------------------------- */
 692 static acpi_status
 693 ec_parse_io_ports(struct acpi_resource *resource, void *context);
 694
 695 static struct acpi_ec *make_acpi_ec(void)
 696 {
 697         struct acpi_ec *ec = kzalloc(sizeof(struct acpi_ec), GFP_KERNEL);
 698         if (!ec)
 699                 return NULL;
 700         ec->flags = 1 << EC_FLAGS_QUERY_PENDING;
 701         mutex_init(&ec->mutex);
 702         init_waitqueue_head(&ec->wait);
 703         INIT_LIST_HEAD(&ec->list);
 704         spin_lock_init(&ec->lock);
 705         return ec;
 706 }
 707
 708 static acpi_status
 709 acpi_ec_register_query_methods(acpi_handle handle, u32 level,
 710                                void *context, void **return_value)
 711 {
 712         char node_name[5];
 713         struct acpi_buffer buffer = { sizeof(node_name), node_name };
 714         struct acpi_ec *ec = context;
 715         int value = 0;
 716         acpi_status status;
 717
 718         status = acpi_get_name(handle, ACPI_SINGLE_NAME, &buffer);
 719
 720         if (ACPI_SUCCESS(status) && sscanf(node_name, "_Q%x", &value) == 1) {
 721                 acpi_ec_add_query_handler(ec, value, handle, NULL, NULL);
 722         }
 723         return AE_OK;
 724 }
 725
 726 static acpi_status
 727 ec_parse_device(acpi_handle handle, u32 Level, void *context, void **retval)
 728 {
 729         acpi_status status;
 730         unsigned long long tmp = 0;
 731
 732         struct acpi_ec *ec = context;
 733
 734         /* clear addr values, ec_parse_io_ports depend on it */
 735         ec->command_addr = ec->data_addr = 0;
 736
 737         status = acpi_walk_resources(handle, METHOD_NAME__CRS,
 738                                      ec_parse_io_ports, ec);
 739         if (ACPI_FAILURE(status))
 740                 return status;
 741
 742         /* Get GPE bit assignment (EC events). */
 743         /* TODO: Add support for _GPE returning a package */
 744         status = acpi_evaluate_integer(handle, "_GPE", NULL, &tmp);
 745         if (ACPI_FAILURE(status))
 746                 return status;
 747         ec->gpe = tmp;
 748         /* Use the global lock for all EC transactions? */
 749         tmp = 0;
 750         acpi_evaluate_integer(handle, "_GLK", NULL, &tmp);
 751         ec->global_lock = tmp;
 752         ec->handle = handle;
 753         return AE_CTRL_TERMINATE;
 754 }
 755
 756 static int ec_install_handlers(struct acpi_ec *ec)
 757 {
 758         acpi_status status;
 759         if (test_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags))
 760                 return 0;
 761         status = acpi_install_gpe_handler(NULL, ec->gpe,
 762                                   ACPI_GPE_EDGE_TRIGGERED,
 763                                   &acpi_ec_gpe_handler, ec);
 764         if (ACPI_FAILURE(status))
 765                 return -ENODEV;
 766
 767         acpi_enable_gpe(NULL, ec->gpe);
 768         status = acpi_install_address_space_handler(ec->handle,
 769                                                     ACPI_ADR_SPACE_EC,
 770                                                     &acpi_ec_space_handler,
 771                                                     NULL, ec);
 772         if (ACPI_FAILURE(status)) {
 773                 if (status == AE_NOT_FOUND) {
 774                         /*
 775                          * Maybe OS fails in evaluating the _REG object.
 776                          * The AE_NOT_FOUND error will be ignored and OS
 777                          * continue to initialize EC.
 778                          */
 779                         printk(KERN_ERR "Fail in evaluating the _REG object"
 780                                 " of EC device. Broken bios is suspected.\n");
 781                 } else {
 782                         acpi_remove_gpe_handler(NULL, ec->gpe,
 783                                 &acpi_ec_gpe_handler);
 784                         acpi_disable_gpe(NULL, ec->gpe);
 785                         return -ENODEV;
 786                 }
 787         }
 788
 789         set_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags);
 790         return 0;
 791 }
 792
 793 static void ec_remove_handlers(struct acpi_ec *ec)
 794 {
 795         acpi_disable_gpe(NULL, ec->gpe);
 796         if (ACPI_FAILURE(acpi_remove_address_space_handler(ec->handle,
 797                                 ACPI_ADR_SPACE_EC, &acpi_ec_space_handler)))
 798                 pr_err(PREFIX "failed to remove space handler\n");
 799         if (ACPI_FAILURE(acpi_remove_gpe_handler(NULL, ec->gpe,
 800                                 &acpi_ec_gpe_handler)))
 801                 pr_err(PREFIX "failed to remove gpe handler\n");
 802         clear_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags);
 803 }
 804
 805 static int acpi_ec_add(struct acpi_device *device)
 806 {
 807         struct acpi_ec *ec = NULL;
 808         int ret;
 809
 810         strcpy(acpi_device_name(device), ACPI_EC_DEVICE_NAME);
 811         strcpy(acpi_device_class(device), ACPI_EC_CLASS);
 812
 813         /* Check for boot EC */
 814         if (boot_ec &&
 815             (boot_ec->handle == device->handle ||
 816              boot_ec->handle == ACPI_ROOT_OBJECT)) {
 817                 ec = boot_ec;
 818                 boot_ec = NULL;
 819         } else {
 820                 ec = make_acpi_ec();
 821                 if (!ec)
 822                         return -ENOMEM;
 823         }
 824         if (ec_parse_device(device->handle, 0, ec, NULL) !=
 825                 AE_CTRL_TERMINATE) {
 826                         kfree(ec);
 827                         return -EINVAL;
 828         }
 829
 830         /* Find and register all query methods */
 831         acpi_walk_namespace(ACPI_TYPE_METHOD, ec->handle, 1,
 832                             acpi_ec_register_query_methods, NULL, ec, NULL);
 833
 834         if (!first_ec)
 835                 first_ec = ec;
 836         device->driver_data = ec;
 837
 838         ret = !!request_region(ec->data_addr, 1, "EC data");
 839         WARN(!ret, "Could not request EC data io port 0x%lx", ec->data_addr);
 840         ret = !!request_region(ec->command_addr, 1, "EC cmd");
 841         WARN(!ret, "Could not request EC cmd io port 0x%lx", ec->command_addr);
 842
 843         pr_info(PREFIX "GPE = 0x%lx, I/O: command/status = 0x%lx, data = 0x%lx\n",
 844                           ec->gpe, ec->command_addr, ec->data_addr);
 845
 846         ret = ec_install_handlers(ec);
 847
 848         /* EC is fully operational, allow queries */
 849         clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags);
 850         return ret;
 851 }
 852
 853 static int acpi_ec_remove(struct acpi_device *device)
 854 {
 855         struct acpi_ec *ec;
 856         struct acpi_ec_query_handler *handler, *tmp;
 857
 858         if (!device)
 859                 return -EINVAL;
 860
 861         ec = acpi_driver_data(device);
 862         ec_remove_handlers(ec);
 863         mutex_lock(&ec->mutex);
 864         list_for_each_entry_safe(handler, tmp, &ec->list, node) {
 865                 list_del(&handler->node);
 866                 kfree(handler);
 867         }
 868         mutex_unlock(&ec->mutex);
 869         release_region(ec->data_addr, 1);
 870         release_region(ec->command_addr, 1);
 871         device->driver_data = NULL;
 872         if (ec == first_ec)
 873                 first_ec = NULL;
 874         kfree(ec);
 875         return 0;
 876 }
 877
 878 static acpi_status
 879 ec_parse_io_ports(struct acpi_resource *resource, void *context)
 880 {
 881         struct acpi_ec *ec = context;
 882
 883         if (resource->type != ACPI_RESOURCE_TYPE_IO)
 884                 return AE_OK;
 885
 886         /*
 887          * The first address region returned is the data port, and
 888          * the second address region returned is the status/command
 889          * port.
 890          */
 891         if (ec->data_addr == 0)
 892                 ec->data_addr = resource->data.io.minimum;
 893         else if (ec->command_addr == 0)
 894                 ec->command_addr = resource->data.io.minimum;
 895         else
 896                 return AE_CTRL_TERMINATE;
 897
 898         return AE_OK;
 899 }
 900
 901 int __init acpi_boot_ec_enable(void)
 902 {
 903         if (!boot_ec || test_bit(EC_FLAGS_HANDLERS_INSTALLED, &boot_ec->flags))
 904                 return 0;
 905         if (!ec_install_handlers(boot_ec)) {
 906                 first_ec = boot_ec;
 907                 return 0;
 908         }
 909         return -EFAULT;
 910 }
 911
 912 static const struct acpi_device_id ec_device_ids[] = {
 913         {"PNP0C09", 0},
 914         {"", 0},
 915 };
 916
 917 /* Some BIOS do not survive early DSDT scan, skip it */
 918 static int ec_skip_dsdt_scan(const struct dmi_system_id *id)
 919 {
 920         EC_FLAGS_SKIP_DSDT_SCAN = 1;
 921         return 0;
 922 }
 923
 924 /* ASUStek often supplies us with broken ECDT, validate it */
 925 static int ec_validate_ecdt(const struct dmi_system_id *id)
 926 {
 927         EC_FLAGS_VALIDATE_ECDT = 1;
 928         return 0;
 929 }
 930
 931 /* MSI EC needs special treatment, enable it */
 932 static int ec_flag_msi(const struct dmi_system_id *id)
 933 {
 934         printk(KERN_DEBUG PREFIX "Detected MSI hardware, enabling workarounds.\n");
 935         EC_FLAGS_MSI = 1;
 936         EC_FLAGS_VALIDATE_ECDT = 1;
 937         return 0;
 938 }
 939
 940 /*
 941  * Clevo M720 notebook actually works ok with IRQ mode, if we lifted
 942  * the GPE storm threshold back to 20
 943  */
 944 static int ec_enlarge_storm_threshold(const struct dmi_system_id *id)
 945 {
 946         pr_debug("Setting the EC GPE storm threshold to 20\n");
 947         ec_storm_threshold  = 20;
 948         return 0;
 949 }
 950
 951 static struct dmi_system_id __initdata ec_dmi_table[] = {
 952         {
 953         ec_skip_dsdt_scan, "Compal JFL92", {
 954         DMI_MATCH(DMI_BIOS_VENDOR, "COMPAL"),
 955         DMI_MATCH(DMI_BOARD_NAME, "JFL92") }, NULL},
 956         {
 957         ec_flag_msi, "MSI hardware", {
 958         DMI_MATCH(DMI_BIOS_VENDOR, "Micro-Star")}, NULL},
 959         {
 960         ec_flag_msi, "MSI hardware", {
 961         DMI_MATCH(DMI_SYS_VENDOR, "Micro-Star")}, NULL},
 962         {
 963         ec_flag_msi, "MSI hardware", {
 964         DMI_MATCH(DMI_CHASSIS_VENDOR, "MICRO-Star")}, NULL},
 965         {
 966         ec_flag_msi, "MSI hardware", {
 967         DMI_MATCH(DMI_CHASSIS_VENDOR, "MICRO-STAR")}, NULL},
 968         {
 969         ec_flag_msi, "Quanta hardware", {
 970         DMI_MATCH(DMI_SYS_VENDOR, "Quanta"),
 971         DMI_MATCH(DMI_PRODUCT_NAME, "TW8/SW8/DW8"),}, NULL},
 972         {
 973         ec_flag_msi, "Quanta hardware", {
 974         DMI_MATCH(DMI_SYS_VENDOR, "Quanta"),
 975         DMI_MATCH(DMI_PRODUCT_NAME, "TW9/SW9"),}, NULL},
 976         {
 977         ec_validate_ecdt, "ASUS hardware", {
 978         DMI_MATCH(DMI_BIOS_VENDOR, "ASUS") }, NULL},
 979         {
 980         ec_validate_ecdt, "ASUS hardware", {
 981         DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTeK Computer Inc.") }, NULL},
 982         {
 983         ec_enlarge_storm_threshold, "CLEVO hardware", {
 984         DMI_MATCH(DMI_SYS_VENDOR, "CLEVO Co."),
 985         DMI_MATCH(DMI_PRODUCT_NAME, "M720T/M730T"),}, NULL},
 986         {},
 987 };
 988
 989 int __init acpi_ec_ecdt_probe(void)
 990 {
 991         acpi_status status;
 992         struct acpi_ec *saved_ec = NULL;
 993         struct acpi_table_ecdt *ecdt_ptr;
 994
 995         boot_ec = make_acpi_ec();
 996         if (!boot_ec)
 997                 return -ENOMEM;
 998         /*
 999          * Generate a boot ec context
1000          */
1001         dmi_check_system(ec_dmi_table);
1002         status = acpi_get_table(ACPI_SIG_ECDT, 1,
1003                                 (struct acpi_table_header **)&ecdt_ptr);
1004         if (ACPI_SUCCESS(status)) {
1005                 pr_info(PREFIX "EC description table is found, configuring boot EC\n");
1006                 boot_ec->command_addr = ecdt_ptr->control.address;
1007                 boot_ec->data_addr = ecdt_ptr->data.address;
1008                 boot_ec->gpe = ecdt_ptr->gpe;
1009                 boot_ec->handle = ACPI_ROOT_OBJECT;
1010                 acpi_get_handle(ACPI_ROOT_OBJECT, ecdt_ptr->id, &boot_ec->handle);
1011                 /* Don't trust ECDT, which comes from ASUSTek */
1012                 if (!EC_FLAGS_VALIDATE_ECDT)
1013                         goto install;
1014                 saved_ec = kmemdup(boot_ec, sizeof(struct acpi_ec), GFP_KERNEL);
1015                 if (!saved_ec)
1016                         return -ENOMEM;
1017         /* fall through */
1018         }
1019
1020         if (EC_FLAGS_SKIP_DSDT_SCAN)
1021                 return -ENODEV;
1022
1023         /* This workaround is needed only on some broken machines,
1024          * which require early EC, but fail to provide ECDT */
1025         printk(KERN_DEBUG PREFIX "Look up EC in DSDT\n");
1026         status = acpi_get_devices(ec_device_ids[0].id, ec_parse_device,
1027                                         boot_ec, NULL);
1028         /* Check that acpi_get_devices actually find something */
1029         if (ACPI_FAILURE(status) || !boot_ec->handle)
1030                 goto error;
1031         if (saved_ec) {
1032                 /* try to find good ECDT from ASUSTek */
1033                 if (saved_ec->command_addr != boot_ec->command_addr ||
1034                     saved_ec->data_addr != boot_ec->data_addr ||
1035                     saved_ec->gpe != boot_ec->gpe ||
1036                     saved_ec->handle != boot_ec->handle)
1037                         pr_info(PREFIX "ASUSTek keeps feeding us with broken "
1038                         "ECDT tables, which are very hard to workaround. "
1039                         "Trying to use DSDT EC info instead. Please send "
1040                         "output of acpidump to linux-acpi@vger.kernel.org\n");
1041                 kfree(saved_ec);
1042                 saved_ec = NULL;
1043         } else {
1044                 /* We really need to limit this workaround, the only ASUS,
1045                 * which needs it, has fake EC._INI method, so use it as flag.
1046                 * Keep boot_ec struct as it will be needed soon.
1047                 */
1048                 acpi_handle dummy;
1049                 if (!dmi_name_in_vendors("ASUS") ||
1050                     ACPI_FAILURE(acpi_get_handle(boot_ec->handle, "_INI",
1051                                                         &dummy)))
1052                         return -ENODEV;
1053         }
1054 install:
1055         if (!ec_install_handlers(boot_ec)) {
1056                 first_ec = boot_ec;
1057                 return 0;
1058         }
1059 error:
1060         kfree(boot_ec);
1061         boot_ec = NULL;
1062         return -ENODEV;
1063 }
1064
1065 static struct acpi_driver acpi_ec_driver = {
1066         .name = "ec",
1067         .class = ACPI_EC_CLASS,
1068         .ids = ec_device_ids,
1069         .ops = {
1070                 .add = acpi_ec_add,
1071                 .remove = acpi_ec_remove,
1072                 },
1073 };
1074
1075 int __init acpi_ec_init(void)
1076 {
1077         int result = 0;
1078
1079         /* Now register the driver for the EC */
1080         result = acpi_bus_register_driver(&acpi_ec_driver);
1081         if (result < 0)
1082                 return -ENODEV;
1083
1084         return result;
1085 }
1086
1087 /* EC driver currently not unloadable */
1088 #if 0
1089 static void __exit acpi_ec_exit(void)
1090 {
1091
1092         acpi_bus_unregister_driver(&acpi_ec_driver);
1093         return;
1094 }
1095 #endif  /* 0 */