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;
 179
 180         spin_lock_irqsave(&ec->lock, flags);
 181         t = ec->curr;
 182         if (!t)
 183                 goto unlock;
 184         if (t->wlen > t->wi) {
 185                 if ((status & ACPI_EC_FLAG_IBF) == 0)
 186                         acpi_ec_write_data(ec,
 187                                 t->wdata[t->wi++]);
 188                 else
 189                         goto err;
 190         } else if (t->rlen > t->ri) {
 191                 if ((status & ACPI_EC_FLAG_OBF) == 1) {
 192                         t->rdata[t->ri++] = acpi_ec_read_data(ec);
 193                         if (t->rlen == t->ri)
 194                                 t->done = true;
 195                 } else
 196                         goto err;
 197         } else if (t->wlen == t->wi &&
 198                    (status & ACPI_EC_FLAG_IBF) == 0)
 199                 t->done = true;
 200         goto unlock;
 201 err:
 202         /*
 203          * If SCI bit is set, then don't think it's a false IRQ
 204          * otherwise will take a not handled IRQ as a false one.
 205          */
 206         if (in_interrupt() && !(status & ACPI_EC_FLAG_SCI))
 207                 ++t->irq_count;
 208
 209 unlock:
 210         spin_unlock_irqrestore(&ec->lock, flags);
 211 }
 212
 213 static int acpi_ec_sync_query(struct acpi_ec *ec);
 214
 215 static int ec_check_sci_sync(struct acpi_ec *ec, u8 state)
 216 {
 217         if (state & ACPI_EC_FLAG_SCI) {
 218                 if (!test_and_set_bit(EC_FLAGS_QUERY_PENDING, &ec->flags))
 219                         return acpi_ec_sync_query(ec);
 220         }
 221         return 0;
 222 }
 223
 224 static int ec_poll(struct acpi_ec *ec)
 225 {
 226         unsigned long flags;
 227         int repeat = 5; /* number of command restarts */
 228         while (repeat--) {
 229                 unsigned long delay = jiffies +
 230                         msecs_to_jiffies(ec_delay);
 231                 do {
 232                         /* don't sleep with disabled interrupts */
 233                         if (EC_FLAGS_MSI || irqs_disabled()) {
 234                                 udelay(ACPI_EC_MSI_UDELAY);
 235                                 if (ec_transaction_done(ec))
 236                                         return 0;
 237                         } else {
 238                                 if (wait_event_timeout(ec->wait,
 239                                                 ec_transaction_done(ec),
 240                                                 msecs_to_jiffies(1)))
 241                                         return 0;
 242                         }
 243                         advance_transaction(ec, acpi_ec_read_status(ec));
 244                 } while (time_before(jiffies, delay));
 245                 pr_debug(PREFIX "controller reset, restart transaction\n");
 246                 spin_lock_irqsave(&ec->lock, flags);
 247                 start_transaction(ec);
 248                 spin_unlock_irqrestore(&ec->lock, flags);
 249         }
 250         return -ETIME;
 251 }
 252
 253 static int acpi_ec_transaction_unlocked(struct acpi_ec *ec,
 254                                         struct transaction *t)
 255 {
 256         unsigned long tmp;
 257         int ret = 0;
 258         if (EC_FLAGS_MSI)
 259                 udelay(ACPI_EC_MSI_UDELAY);
 260         /* start transaction */
 261         spin_lock_irqsave(&ec->lock, tmp);
 262         /* following two actions should be kept atomic */
 263         ec->curr = t;
 264         start_transaction(ec);
 265         if (ec->curr->command == ACPI_EC_COMMAND_QUERY)
 266                 clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags);
 267         spin_unlock_irqrestore(&ec->lock, tmp);
 268         ret = ec_poll(ec);
 269         spin_lock_irqsave(&ec->lock, tmp);
 270         ec->curr = NULL;
 271         spin_unlock_irqrestore(&ec->lock, tmp);
 272         return ret;
 273 }
 274
 275 static int ec_check_ibf0(struct acpi_ec *ec)
 276 {
 277         u8 status = acpi_ec_read_status(ec);
 278         return (status & ACPI_EC_FLAG_IBF) == 0;
 279 }
 280
 281 static int ec_wait_ibf0(struct acpi_ec *ec)
 282 {
 283         unsigned long delay = jiffies + msecs_to_jiffies(ec_delay);
 284         /* interrupt wait manually if GPE mode is not active */
 285         while (time_before(jiffies, delay))
 286                 if (wait_event_timeout(ec->wait, ec_check_ibf0(ec),
 287                                         msecs_to_jiffies(1)))
 288                         return 0;
 289         return -ETIME;
 290 }
 291
 292 static int acpi_ec_transaction(struct acpi_ec *ec, struct transaction *t)
 293 {
 294         int status;
 295         u32 glk;
 296         if (!ec || (!t) || (t->wlen && !t->wdata) || (t->rlen && !t->rdata))
 297                 return -EINVAL;
 298         if (t->rdata)
 299                 memset(t->rdata, 0, t->rlen);
 300         mutex_lock(&ec->mutex);
 301         if (test_bit(EC_FLAGS_BLOCKED, &ec->flags)) {
 302                 status = -EINVAL;
 303                 goto unlock;
 304         }
 305         if (ec->global_lock) {
 306                 status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk);
 307                 if (ACPI_FAILURE(status)) {
 308                         status = -ENODEV;
 309                         goto unlock;
 310                 }
 311         }
 312         if (ec_wait_ibf0(ec)) {
 313                 pr_err(PREFIX "input buffer is not empty, "
 314                                 "aborting transaction\n");
 315                 status = -ETIME;
 316                 goto end;
 317         }
 318         pr_debug(PREFIX "transaction start (cmd=0x%02x, addr=0x%02x)\n",
 319                         t->command, t->wdata ? t->wdata[0] : 0);
 320         /* disable GPE during transaction if storm is detected */
 321         if (test_bit(EC_FLAGS_GPE_STORM, &ec->flags)) {
 322                 /* It has to be disabled, so that it doesn't trigger. */
 323                 acpi_disable_gpe(NULL, ec->gpe);
 324         }
 325
 326         status = acpi_ec_transaction_unlocked(ec, t);
 327
 328         /* check if we received SCI during transaction */
 329         ec_check_sci_sync(ec, acpi_ec_read_status(ec));
 330         if (test_bit(EC_FLAGS_GPE_STORM, &ec->flags)) {
 331                 msleep(1);
 332                 /* It is safe to enable the GPE outside of the transaction. */
 333                 acpi_enable_gpe(NULL, ec->gpe);
 334         } else if (t->irq_count > ec_storm_threshold) {
 335                 pr_info(PREFIX "GPE storm detected(%d GPEs), "
 336                         "transactions will use polling mode\n",
 337                         t->irq_count);
 338                 set_bit(EC_FLAGS_GPE_STORM, &ec->flags);
 339         }
 340         pr_debug(PREFIX "transaction end\n");
 341 end:
 342         if (ec->global_lock)
 343                 acpi_release_global_lock(glk);
 344 unlock:
 345         mutex_unlock(&ec->mutex);
 346         return status;
 347 }
 348
 349 static int acpi_ec_burst_enable(struct acpi_ec *ec)
 350 {
 351         u8 d;
 352         struct transaction t = {.command = ACPI_EC_BURST_ENABLE,
 353                                 .wdata = NULL, .rdata = &d,
 354                                 .wlen = 0, .rlen = 1};
 355
 356         return acpi_ec_transaction(ec, &t);
 357 }
 358
 359 static int acpi_ec_burst_disable(struct acpi_ec *ec)
 360 {
 361         struct transaction t = {.command = ACPI_EC_BURST_DISABLE,
 362                                 .wdata = NULL, .rdata = NULL,
 363                                 .wlen = 0, .rlen = 0};
 364
 365         return (acpi_ec_read_status(ec) & ACPI_EC_FLAG_BURST) ?
 366                                 acpi_ec_transaction(ec, &t) : 0;
 367 }
 368
 369 static int acpi_ec_read(struct acpi_ec *ec, u8 address, u8 * data)
 370 {
 371         int result;
 372         u8 d;
 373         struct transaction t = {.command = ACPI_EC_COMMAND_READ,
 374                                 .wdata = &address, .rdata = &d,
 375                                 .wlen = 1, .rlen = 1};
 376
 377         result = acpi_ec_transaction(ec, &t);
 378         *data = d;
 379         return result;
 380 }
 381
 382 static int acpi_ec_write(struct acpi_ec *ec, u8 address, u8 data)
 383 {
 384         u8 wdata[2] = { address, data };
 385         struct transaction t = {.command = ACPI_EC_COMMAND_WRITE,
 386                                 .wdata = wdata, .rdata = NULL,
 387                                 .wlen = 2, .rlen = 0};
 388
 389         return acpi_ec_transaction(ec, &t);
 390 }
 391
 392 /*
 393  * Externally callable EC access functions. For now, assume 1 EC only
 394  */
 395 int ec_burst_enable(void)
 396 {
 397         if (!first_ec)
 398                 return -ENODEV;
 399         return acpi_ec_burst_enable(first_ec);
 400 }
 401
 402 EXPORT_SYMBOL(ec_burst_enable);
 403
 404 int ec_burst_disable(void)
 405 {
 406         if (!first_ec)
 407                 return -ENODEV;
 408         return acpi_ec_burst_disable(first_ec);
 409 }
 410
 411 EXPORT_SYMBOL(ec_burst_disable);
 412
 413 int ec_read(u8 addr, u8 *val)
 414 {
 415         int err;
 416         u8 temp_data;
 417
 418         if (!first_ec)
 419                 return -ENODEV;
 420
 421         err = acpi_ec_read(first_ec, addr, &temp_data);
 422
 423         if (!err) {
 424                 *val = temp_data;
 425                 return 0;
 426         } else
 427                 return err;
 428 }
 429
 430 EXPORT_SYMBOL(ec_read);
 431
 432 int ec_write(u8 addr, u8 val)
 433 {
 434         int err;
 435
 436         if (!first_ec)
 437                 return -ENODEV;
 438
 439         err = acpi_ec_write(first_ec, addr, val);
 440
 441         return err;
 442 }
 443
 444 EXPORT_SYMBOL(ec_write);
 445
 446 int ec_transaction(u8 command,
 447                    const u8 * wdata, unsigned wdata_len,
 448                    u8 * rdata, unsigned rdata_len)
 449 {
 450         struct transaction t = {.command = command,
 451                                 .wdata = wdata, .rdata = rdata,
 452                                 .wlen = wdata_len, .rlen = rdata_len};
 453         if (!first_ec)
 454                 return -ENODEV;
 455
 456         return acpi_ec_transaction(first_ec, &t);
 457 }
 458
 459 EXPORT_SYMBOL(ec_transaction);
 460
 461 /* Get the handle to the EC device */
 462 acpi_handle ec_get_handle(void)
 463 {
 464         if (!first_ec)
 465                 return NULL;
 466         return first_ec->handle;
 467 }
 468
 469 EXPORT_SYMBOL(ec_get_handle);
 470
 471 void acpi_ec_block_transactions(void)
 472 {
 473         struct acpi_ec *ec = first_ec;
 474
 475         if (!ec)
 476                 return;
 477
 478         mutex_lock(&ec->mutex);
 479         /* Prevent transactions from being carried out */
 480         set_bit(EC_FLAGS_BLOCKED, &ec->flags);
 481         mutex_unlock(&ec->mutex);
 482 }
 483
 484 void acpi_ec_unblock_transactions(void)
 485 {
 486         struct acpi_ec *ec = first_ec;
 487
 488         if (!ec)
 489                 return;
 490
 491         mutex_lock(&ec->mutex);
 492         /* Allow transactions to be carried out again */
 493         clear_bit(EC_FLAGS_BLOCKED, &ec->flags);
 494         mutex_unlock(&ec->mutex);
 495 }
 496
 497 void acpi_ec_unblock_transactions_early(void)
 498 {
 499         /*
 500          * Allow transactions to happen again (this function is called from
 501          * atomic context during wakeup, so we don't need to acquire the mutex).
 502          */
 503         if (first_ec)
 504                 clear_bit(EC_FLAGS_BLOCKED, &first_ec->flags);
 505 }
 506
 507 static int acpi_ec_query_unlocked(struct acpi_ec *ec, u8 * data)
 508 {
 509         int result;
 510         u8 d;
 511         struct transaction t = {.command = ACPI_EC_COMMAND_QUERY,
 512                                 .wdata = NULL, .rdata = &d,
 513                                 .wlen = 0, .rlen = 1};
 514         if (!ec || !data)
 515                 return -EINVAL;
 516         /*
 517          * Query the EC to find out which _Qxx method we need to evaluate.
 518          * Note that successful completion of the query causes the ACPI_EC_SCI
 519          * bit to be cleared (and thus clearing the interrupt source).
 520          */
 521         result = acpi_ec_transaction_unlocked(ec, &t);
 522         if (result)
 523                 return result;
 524         if (!d)
 525                 return -ENODATA;
 526         *data = d;
 527         return 0;
 528 }
 529
 530 /* --------------------------------------------------------------------------
 531                                 Event Management
 532    -------------------------------------------------------------------------- */
 533 int acpi_ec_add_query_handler(struct acpi_ec *ec, u8 query_bit,
 534                               acpi_handle handle, acpi_ec_query_func func,
 535                               void *data)
 536 {
 537         struct acpi_ec_query_handler *handler =
 538             kzalloc(sizeof(struct acpi_ec_query_handler), GFP_KERNEL);
 539         if (!handler)
 540                 return -ENOMEM;
 541
 542         handler->query_bit = query_bit;
 543         handler->handle = handle;
 544         handler->func = func;
 545         handler->data = data;
 546         mutex_lock(&ec->mutex);
 547         list_add(&handler->node, &ec->list);
 548         mutex_unlock(&ec->mutex);
 549         return 0;
 550 }
 551
 552 EXPORT_SYMBOL_GPL(acpi_ec_add_query_handler);
 553
 554 void acpi_ec_remove_query_handler(struct acpi_ec *ec, u8 query_bit)
 555 {
 556         struct acpi_ec_query_handler *handler, *tmp;
 557         mutex_lock(&ec->mutex);
 558         list_for_each_entry_safe(handler, tmp, &ec->list, node) {
 559                 if (query_bit == handler->query_bit) {
 560                         list_del(&handler->node);
 561                         kfree(handler);
 562                 }
 563         }
 564         mutex_unlock(&ec->mutex);
 565 }
 566
 567 EXPORT_SYMBOL_GPL(acpi_ec_remove_query_handler);
 568
 569 static void acpi_ec_run(void *cxt)
 570 {
 571         struct acpi_ec_query_handler *handler = cxt;
 572         if (!handler)
 573                 return;
 574         pr_debug(PREFIX "start query execution\n");
 575         if (handler->func)
 576                 handler->func(handler->data);
 577         else if (handler->handle)
 578                 acpi_evaluate_object(handler->handle, NULL, NULL, NULL);
 579         pr_debug(PREFIX "stop query execution\n");
 580         kfree(handler);
 581 }
 582
 583 static int acpi_ec_sync_query(struct acpi_ec *ec)
 584 {
 585         u8 value = 0;
 586         int status;
 587         struct acpi_ec_query_handler *handler, *copy;
 588         if ((status = acpi_ec_query_unlocked(ec, &value)))
 589                 return status;
 590         list_for_each_entry(handler, &ec->list, node) {
 591                 if (value == handler->query_bit) {
 592                         /* have custom handler for this bit */
 593                         copy = kmalloc(sizeof(*handler), GFP_KERNEL);
 594                         if (!copy)
 595                                 return -ENOMEM;
 596                         memcpy(copy, handler, sizeof(*copy));
 597                         pr_debug(PREFIX "push query execution (0x%2x) on queue\n", value);
 598                         return acpi_os_execute((copy->func) ?
 599                                 OSL_NOTIFY_HANDLER : OSL_GPE_HANDLER,
 600                                 acpi_ec_run, copy);
 601                 }
 602         }
 603         return 0;
 604 }
 605
 606 static void acpi_ec_gpe_query(void *ec_cxt)
 607 {
 608         struct acpi_ec *ec = ec_cxt;
 609         if (!ec)
 610                 return;
 611         mutex_lock(&ec->mutex);
 612         acpi_ec_sync_query(ec);
 613         mutex_unlock(&ec->mutex);
 614 }
 615
 616 static int ec_check_sci(struct acpi_ec *ec, u8 state)
 617 {
 618         if (state & ACPI_EC_FLAG_SCI) {
 619                 if (!test_and_set_bit(EC_FLAGS_QUERY_PENDING, &ec->flags)) {
 620                         pr_debug(PREFIX "push gpe query to the queue\n");
 621                         return acpi_os_execute(OSL_NOTIFY_HANDLER,
 622                                 acpi_ec_gpe_query, ec);
 623                 }
 624         }
 625         return 0;
 626 }
 627
 628 static u32 acpi_ec_gpe_handler(acpi_handle gpe_device,
 629         u32 gpe_number, void *data)
 630 {
 631         struct acpi_ec *ec = data;
 632         u8 status = acpi_ec_read_status(ec);
 633
 634         pr_debug(PREFIX "~~~> interrupt, status:0x%02x\n", status);
 635
 636         advance_transaction(ec, status);
 637         if (ec_transaction_done(ec) &&
 638             (acpi_ec_read_status(ec) & ACPI_EC_FLAG_IBF) == 0) {
 639                 wake_up(&ec->wait);
 640                 ec_check_sci(ec, acpi_ec_read_status(ec));
 641         }
 642         return ACPI_INTERRUPT_HANDLED | ACPI_REENABLE_GPE;
 643 }
 644
 645 /* --------------------------------------------------------------------------
 646                              Address Space Management
 647    -------------------------------------------------------------------------- */
 648
 649 static acpi_status
 650 acpi_ec_space_handler(u32 function, acpi_physical_address address,
 651                       u32 bits, u64 *value64,
 652                       void *handler_context, void *region_context)
 653 {
 654         struct acpi_ec *ec = handler_context;
 655         int result = 0, i, bytes = bits / 8;
 656         u8 *value = (u8 *)value64;
 657
 658         if ((address > 0xFF) || !value || !handler_context)
 659                 return AE_BAD_PARAMETER;
 660
 661         if (function != ACPI_READ && function != ACPI_WRITE)
 662                 return AE_BAD_PARAMETER;
 663
 664         if (EC_FLAGS_MSI || bits > 8)
 665                 acpi_ec_burst_enable(ec);
 666
 667         for (i = 0; i < bytes; ++i, ++address, ++value)
 668                 result = (function == ACPI_READ) ?
 669                         acpi_ec_read(ec, address, value) :
 670                         acpi_ec_write(ec, address, *value);
 671
 672         if (EC_FLAGS_MSI || bits > 8)
 673                 acpi_ec_burst_disable(ec);
 674
 675         switch (result) {
 676         case -EINVAL:
 677                 return AE_BAD_PARAMETER;
 678                 break;
 679         case -ENODEV:
 680                 return AE_NOT_FOUND;
 681                 break;
 682         case -ETIME:
 683                 return AE_TIME;
 684                 break;
 685         default:
 686                 return AE_OK;
 687         }
 688 }
 689
 690 /* --------------------------------------------------------------------------
 691                                Driver Interface
 692    -------------------------------------------------------------------------- */
 693 static acpi_status
 694 ec_parse_io_ports(struct acpi_resource *resource, void *context);
 695
 696 static struct acpi_ec *make_acpi_ec(void)
 697 {
 698         struct acpi_ec *ec = kzalloc(sizeof(struct acpi_ec), GFP_KERNEL);
 699         if (!ec)
 700                 return NULL;
 701         ec->flags = 1 << EC_FLAGS_QUERY_PENDING;
 702         mutex_init(&ec->mutex);
 703         init_waitqueue_head(&ec->wait);
 704         INIT_LIST_HEAD(&ec->list);
 705         spin_lock_init(&ec->lock);
 706         return ec;
 707 }
 708
 709 static acpi_status
 710 acpi_ec_register_query_methods(acpi_handle handle, u32 level,
 711                                void *context, void **return_value)
 712 {
 713         char node_name[5];
 714         struct acpi_buffer buffer = { sizeof(node_name), node_name };
 715         struct acpi_ec *ec = context;
 716         int value = 0;
 717         acpi_status status;
 718
 719         status = acpi_get_name(handle, ACPI_SINGLE_NAME, &buffer);
 720
 721         if (ACPI_SUCCESS(status) && sscanf(node_name, "_Q%x", &value) == 1) {
 722                 acpi_ec_add_query_handler(ec, value, handle, NULL, NULL);
 723         }
 724         return AE_OK;
 725 }
 726
 727 static acpi_status
 728 ec_parse_device(acpi_handle handle, u32 Level, void *context, void **retval)
 729 {
 730         acpi_status status;
 731         unsigned long long tmp = 0;
 732
 733         struct acpi_ec *ec = context;
 734
 735         /* clear addr values, ec_parse_io_ports depend on it */
 736         ec->command_addr = ec->data_addr = 0;
 737
 738         status = acpi_walk_resources(handle, METHOD_NAME__CRS,
 739                                      ec_parse_io_ports, ec);
 740         if (ACPI_FAILURE(status))
 741                 return status;
 742
 743         /* Get GPE bit assignment (EC events). */
 744         /* TODO: Add support for _GPE returning a package */
 745         status = acpi_evaluate_integer(handle, "_GPE", NULL, &tmp);
 746         if (ACPI_FAILURE(status))
 747                 return status;
 748         ec->gpe = tmp;
 749         /* Use the global lock for all EC transactions? */
 750         tmp = 0;
 751         acpi_evaluate_integer(handle, "_GLK", NULL, &tmp);
 752         ec->global_lock = tmp;
 753         ec->handle = handle;
 754         return AE_CTRL_TERMINATE;
 755 }
 756
 757 static int ec_install_handlers(struct acpi_ec *ec)
 758 {
 759         acpi_status status;
 760         if (test_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags))
 761                 return 0;
 762         status = acpi_install_gpe_handler(NULL, ec->gpe,
 763                                   ACPI_GPE_EDGE_TRIGGERED,
 764                                   &acpi_ec_gpe_handler, ec);
 765         if (ACPI_FAILURE(status))
 766                 return -ENODEV;
 767
 768         acpi_enable_gpe(NULL, ec->gpe);
 769         status = acpi_install_address_space_handler(ec->handle,
 770                                                     ACPI_ADR_SPACE_EC,
 771                                                     &acpi_ec_space_handler,
 772                                                     NULL, ec);
 773         if (ACPI_FAILURE(status)) {
 774                 if (status == AE_NOT_FOUND) {
 775                         /*
 776                          * Maybe OS fails in evaluating the _REG object.
 777                          * The AE_NOT_FOUND error will be ignored and OS
 778                          * continue to initialize EC.
 779                          */
 780                         printk(KERN_ERR "Fail in evaluating the _REG object"
 781                                 " of EC device. Broken bios is suspected.\n");
 782                 } else {
 783                         acpi_remove_gpe_handler(NULL, ec->gpe,
 784                                 &acpi_ec_gpe_handler);
 785                         acpi_disable_gpe(NULL, ec->gpe);
 786                         return -ENODEV;
 787                 }
 788         }
 789
 790         set_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags);
 791         return 0;
 792 }
 793
 794 static void ec_remove_handlers(struct acpi_ec *ec)
 795 {
 796         acpi_disable_gpe(NULL, ec->gpe);
 797         if (ACPI_FAILURE(acpi_remove_address_space_handler(ec->handle,
 798                                 ACPI_ADR_SPACE_EC, &acpi_ec_space_handler)))
 799                 pr_err(PREFIX "failed to remove space handler\n");
 800         if (ACPI_FAILURE(acpi_remove_gpe_handler(NULL, ec->gpe,
 801                                 &acpi_ec_gpe_handler)))
 802                 pr_err(PREFIX "failed to remove gpe handler\n");
 803         clear_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags);
 804 }
 805
 806 static int acpi_ec_add(struct acpi_device *device)
 807 {
 808         struct acpi_ec *ec = NULL;
 809         int ret;
 810
 811         strcpy(acpi_device_name(device), ACPI_EC_DEVICE_NAME);
 812         strcpy(acpi_device_class(device), ACPI_EC_CLASS);
 813
 814         /* Check for boot EC */
 815         if (boot_ec &&
 816             (boot_ec->handle == device->handle ||
 817              boot_ec->handle == ACPI_ROOT_OBJECT)) {
 818                 ec = boot_ec;
 819                 boot_ec = NULL;
 820         } else {
 821                 ec = make_acpi_ec();
 822                 if (!ec)
 823                         return -ENOMEM;
 824         }
 825         if (ec_parse_device(device->handle, 0, ec, NULL) !=
 826                 AE_CTRL_TERMINATE) {
 827                         kfree(ec);
 828                         return -EINVAL;
 829         }
 830
 831         /* Find and register all query methods */
 832         acpi_walk_namespace(ACPI_TYPE_METHOD, ec->handle, 1,
 833                             acpi_ec_register_query_methods, NULL, ec, NULL);
 834
 835         if (!first_ec)
 836                 first_ec = ec;
 837         device->driver_data = ec;
 838
 839         ret = !!request_region(ec->data_addr, 1, "EC data");
 840         WARN(!ret, "Could not request EC data io port 0x%lx", ec->data_addr);
 841         ret = !!request_region(ec->command_addr, 1, "EC cmd");
 842         WARN(!ret, "Could not request EC cmd io port 0x%lx", ec->command_addr);
 843
 844         pr_info(PREFIX "GPE = 0x%lx, I/O: command/status = 0x%lx, data = 0x%lx\n",
 845                           ec->gpe, ec->command_addr, ec->data_addr);
 846
 847         ret = ec_install_handlers(ec);
 848
 849         /* EC is fully operational, allow queries */
 850         clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags);
 851         return ret;
 852 }
 853
 854 static int acpi_ec_remove(struct acpi_device *device)
 855 {
 856         struct acpi_ec *ec;
 857         struct acpi_ec_query_handler *handler, *tmp;
 858
 859         if (!device)
 860                 return -EINVAL;
 861
 862         ec = acpi_driver_data(device);
 863         ec_remove_handlers(ec);
 864         mutex_lock(&ec->mutex);
 865         list_for_each_entry_safe(handler, tmp, &ec->list, node) {
 866                 list_del(&handler->node);
 867                 kfree(handler);
 868         }
 869         mutex_unlock(&ec->mutex);
 870         release_region(ec->data_addr, 1);
 871         release_region(ec->command_addr, 1);
 872         device->driver_data = NULL;
 873         if (ec == first_ec)
 874                 first_ec = NULL;
 875         kfree(ec);
 876         return 0;
 877 }
 878
 879 static acpi_status
 880 ec_parse_io_ports(struct acpi_resource *resource, void *context)
 881 {
 882         struct acpi_ec *ec = context;
 883
 884         if (resource->type != ACPI_RESOURCE_TYPE_IO)
 885                 return AE_OK;
 886
 887         /*
 888          * The first address region returned is the data port, and
 889          * the second address region returned is the status/command
 890          * port.
 891          */
 892         if (ec->data_addr == 0)
 893                 ec->data_addr = resource->data.io.minimum;
 894         else if (ec->command_addr == 0)
 895                 ec->command_addr = resource->data.io.minimum;
 896         else
 897                 return AE_CTRL_TERMINATE;
 898
 899         return AE_OK;
 900 }
 901
 902 int __init acpi_boot_ec_enable(void)
 903 {
 904         if (!boot_ec || test_bit(EC_FLAGS_HANDLERS_INSTALLED, &boot_ec->flags))
 905                 return 0;
 906         if (!ec_install_handlers(boot_ec)) {
 907                 first_ec = boot_ec;
 908                 return 0;
 909         }
 910         return -EFAULT;
 911 }
 912
 913 static const struct acpi_device_id ec_device_ids[] = {
 914         {"PNP0C09", 0},
 915         {"", 0},
 916 };
 917
 918 /* Some BIOS do not survive early DSDT scan, skip it */
 919 static int ec_skip_dsdt_scan(const struct dmi_system_id *id)
 920 {
 921         EC_FLAGS_SKIP_DSDT_SCAN = 1;
 922         return 0;
 923 }
 924
 925 /* ASUStek often supplies us with broken ECDT, validate it */
 926 static int ec_validate_ecdt(const struct dmi_system_id *id)
 927 {
 928         EC_FLAGS_VALIDATE_ECDT = 1;
 929         return 0;
 930 }
 931
 932 /* MSI EC needs special treatment, enable it */
 933 static int ec_flag_msi(const struct dmi_system_id *id)
 934 {
 935         printk(KERN_DEBUG PREFIX "Detected MSI hardware, enabling workarounds.\n");
 936         EC_FLAGS_MSI = 1;
 937         EC_FLAGS_VALIDATE_ECDT = 1;
 938         return 0;
 939 }
 940
 941 /*
 942  * Clevo M720 notebook actually works ok with IRQ mode, if we lifted
 943  * the GPE storm threshold back to 20
 944  */
 945 static int ec_enlarge_storm_threshold(const struct dmi_system_id *id)
 946 {
 947         pr_debug("Setting the EC GPE storm threshold to 20\n");
 948         ec_storm_threshold  = 20;
 949         return 0;
 950 }
 951
 952 static struct dmi_system_id __initdata ec_dmi_table[] = {
 953         {
 954         ec_skip_dsdt_scan, "Compal JFL92", {
 955         DMI_MATCH(DMI_BIOS_VENDOR, "COMPAL"),
 956         DMI_MATCH(DMI_BOARD_NAME, "JFL92") }, NULL},
 957         {
 958         ec_flag_msi, "MSI hardware", {
 959         DMI_MATCH(DMI_BIOS_VENDOR, "Micro-Star")}, NULL},
 960         {
 961         ec_flag_msi, "MSI hardware", {
 962         DMI_MATCH(DMI_SYS_VENDOR, "Micro-Star")}, NULL},
 963         {
 964         ec_flag_msi, "MSI hardware", {
 965         DMI_MATCH(DMI_CHASSIS_VENDOR, "MICRO-Star")}, NULL},
 966         {
 967         ec_flag_msi, "MSI hardware", {
 968         DMI_MATCH(DMI_CHASSIS_VENDOR, "MICRO-STAR")}, NULL},
 969         {
 970         ec_flag_msi, "Quanta hardware", {
 971         DMI_MATCH(DMI_SYS_VENDOR, "Quanta"),
 972         DMI_MATCH(DMI_PRODUCT_NAME, "TW8/SW8/DW8"),}, NULL},
 973         {
 974         ec_flag_msi, "Quanta hardware", {
 975         DMI_MATCH(DMI_SYS_VENDOR, "Quanta"),
 976         DMI_MATCH(DMI_PRODUCT_NAME, "TW9/SW9"),}, NULL},
 977         {
 978         ec_validate_ecdt, "ASUS hardware", {
 979         DMI_MATCH(DMI_BIOS_VENDOR, "ASUS") }, NULL},
 980         {
 981         ec_validate_ecdt, "ASUS hardware", {
 982         DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTeK Computer Inc.") }, NULL},
 983         {
 984         ec_enlarge_storm_threshold, "CLEVO hardware", {
 985         DMI_MATCH(DMI_SYS_VENDOR, "CLEVO Co."),
 986         DMI_MATCH(DMI_PRODUCT_NAME, "M720T/M730T"),}, NULL},
 987         {
 988         ec_skip_dsdt_scan, "HP Folio 13", {
 989         DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
 990         DMI_MATCH(DMI_PRODUCT_NAME, "HP Folio 13"),}, NULL},
 991         {
 992         ec_validate_ecdt, "ASUS hardware", {
 993         DMI_MATCH(DMI_SYS_VENDOR, "ASUSTek Computer Inc."),
 994         DMI_MATCH(DMI_PRODUCT_NAME, "L4R"),}, NULL},
 995         {},
 996 };
 997
 998 int __init acpi_ec_ecdt_probe(void)
 999 {
1000         acpi_status status;
1001         struct acpi_ec *saved_ec = NULL;
1002         struct acpi_table_ecdt *ecdt_ptr;
1003
1004         boot_ec = make_acpi_ec();
1005         if (!boot_ec)
1006                 return -ENOMEM;
1007         /*
1008          * Generate a boot ec context
1009          */
1010         dmi_check_system(ec_dmi_table);
1011         status = acpi_get_table(ACPI_SIG_ECDT, 1,
1012                                 (struct acpi_table_header **)&ecdt_ptr);
1013         if (ACPI_SUCCESS(status)) {
1014                 pr_info(PREFIX "EC description table is found, configuring boot EC\n");
1015                 boot_ec->command_addr = ecdt_ptr->control.address;
1016                 boot_ec->data_addr = ecdt_ptr->data.address;
1017                 boot_ec->gpe = ecdt_ptr->gpe;
1018                 boot_ec->handle = ACPI_ROOT_OBJECT;
1019                 acpi_get_handle(ACPI_ROOT_OBJECT, ecdt_ptr->id, &boot_ec->handle);
1020                 /* Don't trust ECDT, which comes from ASUSTek */
1021                 if (!EC_FLAGS_VALIDATE_ECDT)
1022                         goto install;
1023                 saved_ec = kmemdup(boot_ec, sizeof(struct acpi_ec), GFP_KERNEL);
1024                 if (!saved_ec)
1025                         return -ENOMEM;
1026         /* fall through */
1027         }
1028
1029         if (EC_FLAGS_SKIP_DSDT_SCAN)
1030                 return -ENODEV;
1031
1032         /* This workaround is needed only on some broken machines,
1033          * which require early EC, but fail to provide ECDT */
1034         printk(KERN_DEBUG PREFIX "Look up EC in DSDT\n");
1035         status = acpi_get_devices(ec_device_ids[0].id, ec_parse_device,
1036                                         boot_ec, NULL);
1037         /* Check that acpi_get_devices actually find something */
1038         if (ACPI_FAILURE(status) || !boot_ec->handle)
1039                 goto error;
1040         if (saved_ec) {
1041                 /* try to find good ECDT from ASUSTek */
1042                 if (saved_ec->command_addr != boot_ec->command_addr ||
1043                     saved_ec->data_addr != boot_ec->data_addr ||
1044                     saved_ec->gpe != boot_ec->gpe ||
1045                     saved_ec->handle != boot_ec->handle)
1046                         pr_info(PREFIX "ASUSTek keeps feeding us with broken "
1047                         "ECDT tables, which are very hard to workaround. "
1048                         "Trying to use DSDT EC info instead. Please send "
1049                         "output of acpidump to linux-acpi@vger.kernel.org\n");
1050                 kfree(saved_ec);
1051                 saved_ec = NULL;
1052         } else {
1053                 /* We really need to limit this workaround, the only ASUS,
1054                 * which needs it, has fake EC._INI method, so use it as flag.
1055                 * Keep boot_ec struct as it will be needed soon.
1056                 */
1057                 acpi_handle dummy;
1058                 if (!dmi_name_in_vendors("ASUS") ||
1059                     ACPI_FAILURE(acpi_get_handle(boot_ec->handle, "_INI",
1060                                                         &dummy)))
1061                         return -ENODEV;
1062         }
1063 install:
1064         if (!ec_install_handlers(boot_ec)) {
1065                 first_ec = boot_ec;
1066                 return 0;
1067         }
1068 error:
1069         kfree(boot_ec);
1070         boot_ec = NULL;
1071         return -ENODEV;
1072 }
1073
1074 static struct acpi_driver acpi_ec_driver = {
1075         .name = "ec",
1076         .class = ACPI_EC_CLASS,
1077         .ids = ec_device_ids,
1078         .ops = {
1079                 .add = acpi_ec_add,
1080                 .remove = acpi_ec_remove,
1081                 },
1082 };
1083
1084 int __init acpi_ec_init(void)
1085 {
1086         int result = 0;
1087
1088         /* Now register the driver for the EC */
1089         result = acpi_bus_register_driver(&acpi_ec_driver);
1090         if (result < 0)
1091                 return -ENODEV;
1092
1093         return result;
1094 }
1095
1096 /* EC driver currently not unloadable */
1097 #if 0
1098 static void __exit acpi_ec_exit(void)
1099 {
1100
1101         acpi_bus_unregister_driver(&acpi_ec_driver);
1102         return;
1103 }
1104 #endif  /* 0 */