drivers/acpi/ec.c

   1 /*
   2  *  ec.c - ACPI Embedded Controller Driver (v2.1)
   3  *
   4  *  Copyright (C) 2006-2008 Alexey Starikovskiy <[email protected]>
   5  *  Copyright (C) 2006 Denis Sadykov <[email protected]>
   6  *  Copyright (C) 2004 Luming Yu <[email protected]>
   7  *  Copyright (C) 2001, 2002 Andy Grover <[email protected]>
   8  *  Copyright (C) 2001, 2002 Paul Diefenbaugh <[email protected]>
   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         /* false interrupt, state didn't change */
 202         if (in_interrupt())
 203                 ++t->irq_count;
 204 unlock:
 205         spin_unlock_irqrestore(&ec->lock, flags);
 206 }
 207
 208 static int acpi_ec_sync_query(struct acpi_ec *ec);
 209
 210 static int ec_check_sci_sync(struct acpi_ec *ec, u8 state)
 211 {
 212         if (state & ACPI_EC_FLAG_SCI) {
 213                 if (!test_and_set_bit(EC_FLAGS_QUERY_PENDING, &ec->flags))
 214                         return acpi_ec_sync_query(ec);
 215         }
 216         return 0;
 217 }
 218
 219 static int ec_poll(struct acpi_ec *ec)
 220 {
 221         unsigned long flags;
 222         int repeat = 2; /* number of command restarts */
 223         while (repeat--) {
 224                 unsigned long delay = jiffies +
 225                         msecs_to_jiffies(ec_delay);
 226                 do {
 227                         /* don't sleep with disabled interrupts */
 228                         if (EC_FLAGS_MSI || irqs_disabled()) {
 229                                 udelay(ACPI_EC_MSI_UDELAY);
 230                                 if (ec_transaction_done(ec))
 231                                         return 0;
 232                         } else {
 233                                 if (wait_event_timeout(ec->wait,
 234                                                 ec_transaction_done(ec),
 235                                                 msecs_to_jiffies(1)))
 236                                         return 0;
 237                         }
 238                         advance_transaction(ec, acpi_ec_read_status(ec));
 239                 } while (time_before(jiffies, delay));
 240                 if (acpi_ec_read_status(ec) & ACPI_EC_FLAG_IBF)
 241                         break;
 242                 pr_debug(PREFIX "controller reset, restart transaction\n");
 243                 spin_lock_irqsave(&ec->lock, flags);
 244                 start_transaction(ec);
 245                 spin_unlock_irqrestore(&ec->lock, flags);
 246         }
 247         return -ETIME;
 248 }
 249
 250 static int acpi_ec_transaction_unlocked(struct acpi_ec *ec,
 251                                         struct transaction *t)
 252 {
 253         unsigned long tmp;
 254         int ret = 0;
 255         if (EC_FLAGS_MSI)
 256                 udelay(ACPI_EC_MSI_UDELAY);
 257         /* start transaction */
 258         spin_lock_irqsave(&ec->lock, tmp);
 259         /* following two actions should be kept atomic */
 260         ec->curr = t;
 261         start_transaction(ec);
 262         if (ec->curr->command == ACPI_EC_COMMAND_QUERY)
 263                 clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags);
 264         spin_unlock_irqrestore(&ec->lock, tmp);
 265         ret = ec_poll(ec);
 266         spin_lock_irqsave(&ec->lock, tmp);
 267         ec->curr = NULL;
 268         spin_unlock_irqrestore(&ec->lock, tmp);
 269         return ret;
 270 }
 271
 272 static int ec_check_ibf0(struct acpi_ec *ec)
 273 {
 274         u8 status = acpi_ec_read_status(ec);
 275         return (status & ACPI_EC_FLAG_IBF) == 0;
 276 }
 277
 278 static int ec_wait_ibf0(struct acpi_ec *ec)
 279 {
 280         unsigned long delay = jiffies + msecs_to_jiffies(ec_delay);
 281         /* interrupt wait manually if GPE mode is not active */
 282         while (time_before(jiffies, delay))
 283                 if (wait_event_timeout(ec->wait, ec_check_ibf0(ec),
 284                                         msecs_to_jiffies(1)))
 285                         return 0;
 286         return -ETIME;
 287 }
 288
 289 static int acpi_ec_transaction(struct acpi_ec *ec, struct transaction *t)
 290 {
 291         int status;
 292         u32 glk;
 293         if (!ec || (!t) || (t->wlen && !t->wdata) || (t->rlen && !t->rdata))
 294                 return -EINVAL;
 295         if (t->rdata)
 296                 memset(t->rdata, 0, t->rlen);
 297         mutex_lock(&ec->mutex);
 298         if (test_bit(EC_FLAGS_BLOCKED, &ec->flags)) {
 299                 status = -EINVAL;
 300                 goto unlock;
 301         }
 302         if (ec->global_lock) {
 303                 status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk);
 304                 if (ACPI_FAILURE(status)) {
 305                         status = -ENODEV;
 306                         goto unlock;
 307                 }
 308         }
 309         if (ec_wait_ibf0(ec)) {
 310                 pr_err(PREFIX "input buffer is not empty, "
 311                                 "aborting transaction\n");
 312                 status = -ETIME;
 313                 goto end;
 314         }
 315         pr_debug(PREFIX "transaction start (cmd=0x%02x, addr=0x%02x)\n",
 316                         t->command, t->wdata ? t->wdata[0] : 0);
 317         /* disable GPE during transaction if storm is detected */
 318         if (test_bit(EC_FLAGS_GPE_STORM, &ec->flags)) {
 319                 /* It has to be disabled, so that it doesn't trigger. */
 320                 acpi_disable_gpe(NULL, ec->gpe);
 321         }
 322
 323         status = acpi_ec_transaction_unlocked(ec, t);
 324
 325         /* check if we received SCI during transaction */
 326         ec_check_sci_sync(ec, acpi_ec_read_status(ec));
 327         if (test_bit(EC_FLAGS_GPE_STORM, &ec->flags)) {
 328                 msleep(1);
 329                 /* It is safe to enable the GPE outside of the transaction. */
 330                 acpi_enable_gpe(NULL, ec->gpe);
 331         } else if (t->irq_count > ec_storm_threshold) {
 332                 pr_info(PREFIX "GPE storm detected(%d GPEs), "
 333                         "transactions will use polling mode\n",
 334                         t->irq_count);
 335                 set_bit(EC_FLAGS_GPE_STORM, &ec->flags);
 336         }
 337         pr_debug(PREFIX "transaction end\n");
 338 end:
 339         if (ec->global_lock)
 340                 acpi_release_global_lock(glk);
 341 unlock:
 342         mutex_unlock(&ec->mutex);
 343         return status;
 344 }
 345
 346 static int acpi_ec_burst_enable(struct acpi_ec *ec)
 347 {
 348         u8 d;
 349         struct transaction t = {.command = ACPI_EC_BURST_ENABLE,
 350                                 .wdata = NULL, .rdata = &d,
 351                                 .wlen = 0, .rlen = 1};
 352
 353         return acpi_ec_transaction(ec, &t);
 354 }
 355
 356 static int acpi_ec_burst_disable(struct acpi_ec *ec)
 357 {
 358         struct transaction t = {.command = ACPI_EC_BURST_DISABLE,
 359                                 .wdata = NULL, .rdata = NULL,
 360                                 .wlen = 0, .rlen = 0};
 361
 362         return (acpi_ec_read_status(ec) & ACPI_EC_FLAG_BURST) ?
 363                                 acpi_ec_transaction(ec, &t) : 0;
 364 }
 365
 366 static int acpi_ec_read(struct acpi_ec *ec, u8 address, u8 * data)
 367 {
 368         int result;
 369         u8 d;
 370         struct transaction t = {.command = ACPI_EC_COMMAND_READ,
 371                                 .wdata = &address, .rdata = &d,
 372                                 .wlen = 1, .rlen = 1};
 373
 374         result = acpi_ec_transaction(ec, &t);
 375         *data = d;
 376         return result;
 377 }
 378
 379 static int acpi_ec_write(struct acpi_ec *ec, u8 address, u8 data)
 380 {
 381         u8 wdata[2] = { address, data };
 382         struct transaction t = {.command = ACPI_EC_COMMAND_WRITE,
 383                                 .wdata = wdata, .rdata = NULL,
 384                                 .wlen = 2, .rlen = 0};
 385
 386         return acpi_ec_transaction(ec, &t);
 387 }
 388
 389 /*
 390  * Externally callable EC access functions. For now, assume 1 EC only
 391  */
 392 int ec_burst_enable(void)
 393 {
 394         if (!first_ec)
 395                 return -ENODEV;
 396         return acpi_ec_burst_enable(first_ec);
 397 }
 398
 399 EXPORT_SYMBOL(ec_burst_enable);
 400
 401 int ec_burst_disable(void)
 402 {
 403         if (!first_ec)
 404                 return -ENODEV;
 405         return acpi_ec_burst_disable(first_ec);
 406 }
 407
 408 EXPORT_SYMBOL(ec_burst_disable);
 409
 410 int ec_read(u8 addr, u8 *val)
 411 {
 412         int err;
 413         u8 temp_data;
 414
 415         if (!first_ec)
 416                 return -ENODEV;
 417
 418         err = acpi_ec_read(first_ec, addr, &temp_data);
 419
 420         if (!err) {
 421                 *val = temp_data;
 422                 return 0;
 423         } else
 424                 return err;
 425 }
 426
 427 EXPORT_SYMBOL(ec_read);
 428
 429 int ec_write(u8 addr, u8 val)
 430 {
 431         int err;
 432
 433         if (!first_ec)
 434                 return -ENODEV;
 435
 436         err = acpi_ec_write(first_ec, addr, val);
 437
 438         return err;
 439 }
 440
 441 EXPORT_SYMBOL(ec_write);
 442
 443 int ec_transaction(u8 command,
 444                    const u8 * wdata, unsigned wdata_len,
 445                    u8 * rdata, unsigned rdata_len)
 446 {
 447         struct transaction t = {.command = command,
 448                                 .wdata = wdata, .rdata = rdata,
 449                                 .wlen = wdata_len, .rlen = rdata_len};
 450         if (!first_ec)
 451                 return -ENODEV;
 452
 453         return acpi_ec_transaction(first_ec, &t);
 454 }
 455
 456 EXPORT_SYMBOL(ec_transaction);
 457
 458 /* Get the handle to the EC device */
 459 acpi_handle ec_get_handle(void)
 460 {
 461         if (!first_ec)
 462                 return NULL;
 463         return first_ec->handle;
 464 }
 465
 466 EXPORT_SYMBOL(ec_get_handle);
 467
 468 void acpi_ec_block_transactions(void)
 469 {
 470         struct acpi_ec *ec = first_ec;
 471
 472         if (!ec)
 473                 return;
 474
 475         mutex_lock(&ec->mutex);
 476         /* Prevent transactions from being carried out */
 477         set_bit(EC_FLAGS_BLOCKED, &ec->flags);
 478         mutex_unlock(&ec->mutex);
 479 }
 480
 481 void acpi_ec_unblock_transactions(void)
 482 {
 483         struct acpi_ec *ec = first_ec;
 484
 485         if (!ec)
 486                 return;
 487
 488         mutex_lock(&ec->mutex);
 489         /* Allow transactions to be carried out again */
 490         clear_bit(EC_FLAGS_BLOCKED, &ec->flags);
 491         mutex_unlock(&ec->mutex);
 492 }
 493
 494 void acpi_ec_unblock_transactions_early(void)
 495 {
 496         /*
 497          * Allow transactions to happen again (this function is called from
 498          * atomic context during wakeup, so we don't need to acquire the mutex).
 499          */
 500         if (first_ec)
 501                 clear_bit(EC_FLAGS_BLOCKED, &first_ec->flags);
 502 }
 503
 504 static int acpi_ec_query_unlocked(struct acpi_ec *ec, u8 * data)
 505 {
 506         int result;
 507         u8 d;
 508         struct transaction t = {.command = ACPI_EC_COMMAND_QUERY,
 509                                 .wdata = NULL, .rdata = &d,
 510                                 .wlen = 0, .rlen = 1};
 511         if (!ec || !data)
 512                 return -EINVAL;
 513         /*
 514          * Query the EC to find out which _Qxx method we need to evaluate.
 515          * Note that successful completion of the query causes the ACPI_EC_SCI
 516          * bit to be cleared (and thus clearing the interrupt source).
 517          */
 518         result = acpi_ec_transaction_unlocked(ec, &t);
 519         if (result)
 520                 return result;
 521         if (!d)
 522                 return -ENODATA;
 523         *data = d;
 524         return 0;
 525 }
 526
 527 /* --------------------------------------------------------------------------
 528                                 Event Management
 529    -------------------------------------------------------------------------- */
 530 int acpi_ec_add_query_handler(struct acpi_ec *ec, u8 query_bit,
 531                               acpi_handle handle, acpi_ec_query_func func,
 532                               void *data)
 533 {
 534         struct acpi_ec_query_handler *handler =
 535             kzalloc(sizeof(struct acpi_ec_query_handler), GFP_KERNEL);
 536         if (!handler)
 537                 return -ENOMEM;
 538
 539         handler->query_bit = query_bit;
 540         handler->handle = handle;
 541         handler->func = func;
 542         handler->data = data;
 543         mutex_lock(&ec->mutex);
 544         list_add(&handler->node, &ec->list);
 545         mutex_unlock(&ec->mutex);
 546         return 0;
 547 }
 548
 549 EXPORT_SYMBOL_GPL(acpi_ec_add_query_handler);
 550
 551 void acpi_ec_remove_query_handler(struct acpi_ec *ec, u8 query_bit)
 552 {
 553         struct acpi_ec_query_handler *handler, *tmp;
 554         mutex_lock(&ec->mutex);
 555         list_for_each_entry_safe(handler, tmp, &ec->list, node) {
 556                 if (query_bit == handler->query_bit) {
 557                         list_del(&handler->node);
 558                         kfree(handler);
 559                 }
 560         }
 561         mutex_unlock(&ec->mutex);
 562 }
 563
 564 EXPORT_SYMBOL_GPL(acpi_ec_remove_query_handler);
 565
 566 static void acpi_ec_run(void *cxt)
 567 {
 568         struct acpi_ec_query_handler *handler = cxt;
 569         if (!handler)
 570                 return;
 571         pr_debug(PREFIX "start query execution\n");
 572         if (handler->func)
 573                 handler->func(handler->data);
 574         else if (handler->handle)
 575                 acpi_evaluate_object(handler->handle, NULL, NULL, NULL);
 576         pr_debug(PREFIX "stop query execution\n");
 577         kfree(handler);
 578 }
 579
 580 static int acpi_ec_sync_query(struct acpi_ec *ec)
 581 {
 582         u8 value = 0;
 583         int status;
 584         struct acpi_ec_query_handler *handler, *copy;
 585         if ((status = acpi_ec_query_unlocked(ec, &value)))
 586                 return status;
 587         list_for_each_entry(handler, &ec->list, node) {
 588                 if (value == handler->query_bit) {
 589                         /* have custom handler for this bit */
 590                         copy = kmalloc(sizeof(*handler), GFP_KERNEL);
 591                         if (!copy)
 592                                 return -ENOMEM;
 593                         memcpy(copy, handler, sizeof(*copy));
 594                         pr_debug(PREFIX "push query execution (0x%2x) on queue\n", value);
 595                         return acpi_os_execute((copy->func) ?
 596                                 OSL_NOTIFY_HANDLER : OSL_GPE_HANDLER,
 597                                 acpi_ec_run, copy);
 598                 }
 599         }
 600         return 0;
 601 }
 602
 603 static void acpi_ec_gpe_query(void *ec_cxt)
 604 {
 605         struct acpi_ec *ec = ec_cxt;
 606         if (!ec)
 607                 return;
 608         mutex_lock(&ec->mutex);
 609         acpi_ec_sync_query(ec);
 610         mutex_unlock(&ec->mutex);
 611 }
 612
 613 static int ec_check_sci(struct acpi_ec *ec, u8 state)
 614 {
 615         if (state & ACPI_EC_FLAG_SCI) {
 616                 if (!test_and_set_bit(EC_FLAGS_QUERY_PENDING, &ec->flags)) {
 617                         pr_debug(PREFIX "push gpe query to the queue\n");
 618                         return acpi_os_execute(OSL_NOTIFY_HANDLER,
 619                                 acpi_ec_gpe_query, ec);
 620                 }
 621         }
 622         return 0;
 623 }
 624
 625 static u32 acpi_ec_gpe_handler(acpi_handle gpe_device,
 626         u32 gpe_number, void *data)
 627 {
 628         struct acpi_ec *ec = data;
 629         u8 status = acpi_ec_read_status(ec);
 630
 631         pr_debug(PREFIX "~~~> interrupt, status:0x%02x\n", status);
 632
 633         advance_transaction(ec, status);
 634         if (ec_transaction_done(ec) &&
 635             (acpi_ec_read_status(ec) & ACPI_EC_FLAG_IBF) == 0) {
 636                 wake_up(&ec->wait);
 637                 ec_check_sci(ec, acpi_ec_read_status(ec));
 638         }
 639         return ACPI_INTERRUPT_HANDLED | ACPI_REENABLE_GPE;
 640 }
 641
 642 /* --------------------------------------------------------------------------
 643                              Address Space Management
 644    -------------------------------------------------------------------------- */
 645
 646 static acpi_status
 647 acpi_ec_space_handler(u32 function, acpi_physical_address address,
 648                       u32 bits, u64 *value64,
 649                       void *handler_context, void *region_context)
 650 {
 651         struct acpi_ec *ec = handler_context;
 652         int result = 0, i, bytes = bits / 8;
 653         u8 *value = (u8 *)value64;
 654
 655         if ((address > 0xFF) || !value || !handler_context)
 656                 return AE_BAD_PARAMETER;
 657
 658         if (function != ACPI_READ && function != ACPI_WRITE)
 659                 return AE_BAD_PARAMETER;
 660
 661         if (EC_FLAGS_MSI || bits > 8)
 662                 acpi_ec_burst_enable(ec);
 663
 664         for (i = 0; i < bytes; ++i, ++address, ++value)
 665                 result = (function == ACPI_READ) ?
 666                         acpi_ec_read(ec, address, value) :
 667                         acpi_ec_write(ec, address, *value);
 668
 669         if (EC_FLAGS_MSI || bits > 8)
 670                 acpi_ec_burst_disable(ec);
 671
 672         switch (result) {
 673         case -EINVAL:
 674                 return AE_BAD_PARAMETER;
 675                 break;
 676         case -ENODEV:
 677                 return AE_NOT_FOUND;
 678                 break;
 679         case -ETIME:
 680                 return AE_TIME;
 681                 break;
 682         default:
 683                 return AE_OK;
 684         }
 685 }
 686
 687 /* --------------------------------------------------------------------------
 688                                Driver Interface
 689    -------------------------------------------------------------------------- */
 690 static acpi_status
 691 ec_parse_io_ports(struct acpi_resource *resource, void *context);
 692
 693 static struct acpi_ec *make_acpi_ec(void)
 694 {
 695         struct acpi_ec *ec = kzalloc(sizeof(struct acpi_ec), GFP_KERNEL);
 696         if (!ec)
 697                 return NULL;
 698         ec->flags = 1 << EC_FLAGS_QUERY_PENDING;
 699         mutex_init(&ec->mutex);
 700         init_waitqueue_head(&ec->wait);
 701         INIT_LIST_HEAD(&ec->list);
 702         spin_lock_init(&ec->lock);
 703         return ec;
 704 }
 705
 706 static acpi_status
 707 acpi_ec_register_query_methods(acpi_handle handle, u32 level,
 708                                void *context, void **return_value)
 709 {
 710         char node_name[5];
 711         struct acpi_buffer buffer = { sizeof(node_name), node_name };
 712         struct acpi_ec *ec = context;
 713         int value = 0;
 714         acpi_status status;
 715
 716         status = acpi_get_name(handle, ACPI_SINGLE_NAME, &buffer);
 717
 718         if (ACPI_SUCCESS(status) && sscanf(node_name, "_Q%x", &value) == 1) {
 719                 acpi_ec_add_query_handler(ec, value, handle, NULL, NULL);
 720         }
 721         return AE_OK;
 722 }
 723
 724 static acpi_status
 725 ec_parse_device(acpi_handle handle, u32 Level, void *context, void **retval)
 726 {
 727         acpi_status status;
 728         unsigned long long tmp = 0;
 729
 730         struct acpi_ec *ec = context;
 731
 732         /* clear addr values, ec_parse_io_ports depend on it */
 733         ec->command_addr = ec->data_addr = 0;
 734
 735         status = acpi_walk_resources(handle, METHOD_NAME__CRS,
 736                                      ec_parse_io_ports, ec);
 737         if (ACPI_FAILURE(status))
 738                 return status;
 739
 740         /* Get GPE bit assignment (EC events). */
 741         /* TODO: Add support for _GPE returning a package */
 742         status = acpi_evaluate_integer(handle, "_GPE", NULL, &tmp);
 743         if (ACPI_FAILURE(status))
 744                 return status;
 745         ec->gpe = tmp;
 746         /* Use the global lock for all EC transactions? */
 747         tmp = 0;
 748         acpi_evaluate_integer(handle, "_GLK", NULL, &tmp);
 749         ec->global_lock = tmp;
 750         ec->handle = handle;
 751         return AE_CTRL_TERMINATE;
 752 }
 753
 754 static int ec_install_handlers(struct acpi_ec *ec)
 755 {
 756         acpi_status status;
 757         if (test_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags))
 758                 return 0;
 759         status = acpi_install_gpe_handler(NULL, ec->gpe,
 760                                   ACPI_GPE_EDGE_TRIGGERED,
 761                                   &acpi_ec_gpe_handler, ec);
 762         if (ACPI_FAILURE(status))
 763                 return -ENODEV;
 764
 765         acpi_enable_gpe(NULL, ec->gpe);
 766         status = acpi_install_address_space_handler(ec->handle,
 767                                                     ACPI_ADR_SPACE_EC,
 768                                                     &acpi_ec_space_handler,
 769                                                     NULL, ec);
 770         if (ACPI_FAILURE(status)) {
 771                 if (status == AE_NOT_FOUND) {
 772                         /*
 773                          * Maybe OS fails in evaluating the _REG object.
 774                          * The AE_NOT_FOUND error will be ignored and OS
 775                          * continue to initialize EC.
 776                          */
 777                         printk(KERN_ERR "Fail in evaluating the _REG object"
 778                                 " of EC device. Broken bios is suspected.\n");
 779                 } else {
 780                         acpi_remove_gpe_handler(NULL, ec->gpe,
 781                                 &acpi_ec_gpe_handler);
 782                         acpi_disable_gpe(NULL, ec->gpe);
 783                         return -ENODEV;
 784                 }
 785         }
 786
 787         set_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags);
 788         return 0;
 789 }
 790
 791 static void ec_remove_handlers(struct acpi_ec *ec)
 792 {
 793         acpi_disable_gpe(NULL, ec->gpe);
 794         if (ACPI_FAILURE(acpi_remove_address_space_handler(ec->handle,
 795                                 ACPI_ADR_SPACE_EC, &acpi_ec_space_handler)))
 796                 pr_err(PREFIX "failed to remove space handler\n");
 797         if (ACPI_FAILURE(acpi_remove_gpe_handler(NULL, ec->gpe,
 798                                 &acpi_ec_gpe_handler)))
 799                 pr_err(PREFIX "failed to remove gpe handler\n");
 800         clear_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags);
 801 }
 802
 803 static int acpi_ec_add(struct acpi_device *device)
 804 {
 805         struct acpi_ec *ec = NULL;
 806         int ret;
 807
 808         strcpy(acpi_device_name(device), ACPI_EC_DEVICE_NAME);
 809         strcpy(acpi_device_class(device), ACPI_EC_CLASS);
 810
 811         /* Check for boot EC */
 812         if (boot_ec &&
 813             (boot_ec->handle == device->handle ||
 814              boot_ec->handle == ACPI_ROOT_OBJECT)) {
 815                 ec = boot_ec;
 816                 boot_ec = NULL;
 817         } else {
 818                 ec = make_acpi_ec();
 819                 if (!ec)
 820                         return -ENOMEM;
 821         }
 822         if (ec_parse_device(device->handle, 0, ec, NULL) !=
 823                 AE_CTRL_TERMINATE) {
 824                         kfree(ec);
 825                         return -EINVAL;
 826         }
 827
 828         /* Find and register all query methods */
 829         acpi_walk_namespace(ACPI_TYPE_METHOD, ec->handle, 1,
 830                             acpi_ec_register_query_methods, NULL, ec, NULL);
 831
 832         if (!first_ec)
 833                 first_ec = ec;
 834         device->driver_data = ec;
 835
 836         ret = !!request_region(ec->data_addr, 1, "EC data");
 837         WARN(!ret, "Could not request EC data io port 0x%lx", ec->data_addr);
 838         ret = !!request_region(ec->command_addr, 1, "EC cmd");
 839         WARN(!ret, "Could not request EC cmd io port 0x%lx", ec->command_addr);
 840
 841         pr_info(PREFIX "GPE = 0x%lx, I/O: command/status = 0x%lx, data = 0x%lx\n",
 842                           ec->gpe, ec->command_addr, ec->data_addr);
 843
 844         ret = ec_install_handlers(ec);
 845
 846         /* EC is fully operational, allow queries */
 847         clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags);
 848         return ret;
 849 }
 850
 851 static int acpi_ec_remove(struct acpi_device *device, int type)
 852 {
 853         struct acpi_ec *ec;
 854         struct acpi_ec_query_handler *handler, *tmp;
 855
 856         if (!device)
 857                 return -EINVAL;
 858
 859         ec = acpi_driver_data(device);
 860         ec_remove_handlers(ec);
 861         mutex_lock(&ec->mutex);
 862         list_for_each_entry_safe(handler, tmp, &ec->list, node) {
 863                 list_del(&handler->node);
 864                 kfree(handler);
 865         }
 866         mutex_unlock(&ec->mutex);
 867         release_region(ec->data_addr, 1);
 868         release_region(ec->command_addr, 1);
 869         device->driver_data = NULL;
 870         if (ec == first_ec)
 871                 first_ec = NULL;
 872         kfree(ec);
 873         return 0;
 874 }
 875
 876 static acpi_status
 877 ec_parse_io_ports(struct acpi_resource *resource, void *context)
 878 {
 879         struct acpi_ec *ec = context;
 880
 881         if (resource->type != ACPI_RESOURCE_TYPE_IO)
 882                 return AE_OK;
 883
 884         /*
 885          * The first address region returned is the data port, and
 886          * the second address region returned is the status/command
 887          * port.
 888          */
 889         if (ec->data_addr == 0)
 890                 ec->data_addr = resource->data.io.minimum;
 891         else if (ec->command_addr == 0)
 892                 ec->command_addr = resource->data.io.minimum;
 893         else
 894                 return AE_CTRL_TERMINATE;
 895
 896         return AE_OK;
 897 }
 898
 899 int __init acpi_boot_ec_enable(void)
 900 {
 901         if (!boot_ec || test_bit(EC_FLAGS_HANDLERS_INSTALLED, &boot_ec->flags))
 902                 return 0;
 903         if (!ec_install_handlers(boot_ec)) {
 904                 first_ec = boot_ec;
 905                 return 0;
 906         }
 907         return -EFAULT;
 908 }
 909
 910 static const struct acpi_device_id ec_device_ids[] = {
 911         {"PNP0C09", 0},
 912         {"", 0},
 913 };
 914
 915 /* Some BIOS do not survive early DSDT scan, skip it */
 916 static int ec_skip_dsdt_scan(const struct dmi_system_id *id)
 917 {
 918         EC_FLAGS_SKIP_DSDT_SCAN = 1;
 919         return 0;
 920 }
 921
 922 /* ASUStek often supplies us with broken ECDT, validate it */
 923 static int ec_validate_ecdt(const struct dmi_system_id *id)
 924 {
 925         EC_FLAGS_VALIDATE_ECDT = 1;
 926         return 0;
 927 }
 928
 929 /* MSI EC needs special treatment, enable it */
 930 static int ec_flag_msi(const struct dmi_system_id *id)
 931 {
 932         printk(KERN_DEBUG PREFIX "Detected MSI hardware, enabling workarounds.\n");
 933         EC_FLAGS_MSI = 1;
 934         EC_FLAGS_VALIDATE_ECDT = 1;
 935         return 0;
 936 }
 937
 938 /*
 939  * Clevo M720 notebook actually works ok with IRQ mode, if we lifted
 940  * the GPE storm threshold back to 20
 941  */
 942 static int ec_enlarge_storm_threshold(const struct dmi_system_id *id)
 943 {
 944         pr_debug("Setting the EC GPE storm threshold to 20\n");
 945         ec_storm_threshold  = 20;
 946         return 0;
 947 }
 948
 949 static struct dmi_system_id __initdata ec_dmi_table[] = {
 950         {
 951         ec_skip_dsdt_scan, "Compal JFL92", {
 952         DMI_MATCH(DMI_BIOS_VENDOR, "COMPAL"),
 953         DMI_MATCH(DMI_BOARD_NAME, "JFL92") }, NULL},
 954         {
 955         ec_flag_msi, "MSI hardware", {
 956         DMI_MATCH(DMI_BIOS_VENDOR, "Micro-Star")}, NULL},
 957         {
 958         ec_flag_msi, "MSI hardware", {
 959         DMI_MATCH(DMI_SYS_VENDOR, "Micro-Star")}, NULL},
 960         {
 961         ec_flag_msi, "MSI hardware", {
 962         DMI_MATCH(DMI_CHASSIS_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, "Quanta hardware", {
 968         DMI_MATCH(DMI_SYS_VENDOR, "Quanta"),
 969         DMI_MATCH(DMI_PRODUCT_NAME, "TW8/SW8/DW8"),}, NULL},
 970         {
 971         ec_flag_msi, "Quanta hardware", {
 972         DMI_MATCH(DMI_SYS_VENDOR, "Quanta"),
 973         DMI_MATCH(DMI_PRODUCT_NAME, "TW9/SW9"),}, NULL},
 974         {
 975         ec_validate_ecdt, "ASUS hardware", {
 976         DMI_MATCH(DMI_BIOS_VENDOR, "ASUS") }, NULL},
 977         {
 978         ec_validate_ecdt, "ASUS hardware", {
 979         DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTeK Computer Inc.") }, NULL},
 980         {
 981         ec_enlarge_storm_threshold, "CLEVO hardware", {
 982         DMI_MATCH(DMI_SYS_VENDOR, "CLEVO Co."),
 983         DMI_MATCH(DMI_PRODUCT_NAME, "M720T/M730T"),}, NULL},
 984         {},
 985 };
 986
 987 int __init acpi_ec_ecdt_probe(void)
 988 {
 989         acpi_status status;
 990         struct acpi_ec *saved_ec = NULL;
 991         struct acpi_table_ecdt *ecdt_ptr;
 992
 993         boot_ec = make_acpi_ec();
 994         if (!boot_ec)
 995                 return -ENOMEM;
 996         /*
 997          * Generate a boot ec context
 998          */
 999         dmi_check_system(ec_dmi_table);
1000         status = acpi_get_table(ACPI_SIG_ECDT, 1,
1001                                 (struct acpi_table_header **)&ecdt_ptr);
1002         if (ACPI_SUCCESS(status)) {
1003                 pr_info(PREFIX "EC description table is found, configuring boot EC\n");
1004                 boot_ec->command_addr = ecdt_ptr->control.address;
1005                 boot_ec->data_addr = ecdt_ptr->data.address;
1006                 boot_ec->gpe = ecdt_ptr->gpe;
1007                 boot_ec->handle = ACPI_ROOT_OBJECT;
1008                 acpi_get_handle(ACPI_ROOT_OBJECT, ecdt_ptr->id, &boot_ec->handle);
1009                 /* Don't trust ECDT, which comes from ASUSTek */
1010                 if (!EC_FLAGS_VALIDATE_ECDT)
1011                         goto install;
1012                 saved_ec = kmemdup(boot_ec, sizeof(struct acpi_ec), GFP_KERNEL);
1013                 if (!saved_ec)
1014                         return -ENOMEM;
1015         /* fall through */
1016         }
1017
1018         if (EC_FLAGS_SKIP_DSDT_SCAN)
1019                 return -ENODEV;
1020
1021         /* This workaround is needed only on some broken machines,
1022          * which require early EC, but fail to provide ECDT */
1023         printk(KERN_DEBUG PREFIX "Look up EC in DSDT\n");
1024         status = acpi_get_devices(ec_device_ids[0].id, ec_parse_device,
1025                                         boot_ec, NULL);
1026         /* Check that acpi_get_devices actually find something */
1027         if (ACPI_FAILURE(status) || !boot_ec->handle)
1028                 goto error;
1029         if (saved_ec) {
1030                 /* try to find good ECDT from ASUSTek */
1031                 if (saved_ec->command_addr != boot_ec->command_addr ||
1032                     saved_ec->data_addr != boot_ec->data_addr ||
1033                     saved_ec->gpe != boot_ec->gpe ||
1034                     saved_ec->handle != boot_ec->handle)
1035                         pr_info(PREFIX "ASUSTek keeps feeding us with broken "
1036                         "ECDT tables, which are very hard to workaround. "
1037                         "Trying to use DSDT EC info instead. Please send "
1038                         "output of acpidump to [email protected]\n");
1039                 kfree(saved_ec);
1040                 saved_ec = NULL;
1041         } else {
1042                 /* We really need to limit this workaround, the only ASUS,
1043                 * which needs it, has fake EC._INI method, so use it as flag.
1044                 * Keep boot_ec struct as it will be needed soon.
1045                 */
1046                 acpi_handle dummy;
1047                 if (!dmi_name_in_vendors("ASUS") ||
1048                     ACPI_FAILURE(acpi_get_handle(boot_ec->handle, "_INI",
1049                                                         &dummy)))
1050                         return -ENODEV;
1051         }
1052 install:
1053         if (!ec_install_handlers(boot_ec)) {
1054                 first_ec = boot_ec;
1055                 return 0;
1056         }
1057 error:
1058         kfree(boot_ec);
1059         boot_ec = NULL;
1060         return -ENODEV;
1061 }
1062
1063 static struct acpi_driver acpi_ec_driver = {
1064         .name = "ec",
1065         .class = ACPI_EC_CLASS,
1066         .ids = ec_device_ids,
1067         .ops = {
1068                 .add = acpi_ec_add,
1069                 .remove = acpi_ec_remove,
1070                 },
1071 };
1072
1073 int __init acpi_ec_init(void)
1074 {
1075         int result = 0;
1076
1077         /* Now register the driver for the EC */
1078         result = acpi_bus_register_driver(&acpi_ec_driver);
1079         if (result < 0)
1080                 return -ENODEV;
1081
1082         return result;
1083 }
1084
1085 /* EC driver currently not unloadable */
1086 #if 0
1087 static void __exit acpi_ec_exit(void)
1088 {
1089
1090         acpi_bus_unregister_driver(&acpi_ec_driver);
1091         return;
1092 }
1093 #endif  /* 0 */