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_CDELAY          10      /* Wait 10us before polling EC */
  73 #define ACPI_EC_MSI_UDELAY      550     /* Wait 550us for MSI EC */
  74
  75 #define ACPI_EC_STORM_THRESHOLD 8       /* number of false interrupts
  76                                            per one transaction */
  77
  78 enum {
  79         EC_FLAGS_QUERY_PENDING,         /* Query is pending */
  80         EC_FLAGS_GPE_STORM,             /* GPE storm detected */
  81         EC_FLAGS_HANDLERS_INSTALLED,    /* Handlers for GPE and
  82                                          * OpReg are installed */
  83         EC_FLAGS_BLOCKED,               /* Transactions are blocked */
  84 };
  85
  86 /* If we find an EC via the ECDT, we need to keep a ptr to its context */
  87 /* External interfaces use first EC only, so remember */
  88 typedef int (*acpi_ec_query_func) (void *data);
  89
  90 struct acpi_ec_query_handler {
  91         struct list_head node;
  92         acpi_ec_query_func func;
  93         acpi_handle handle;
  94         void *data;
  95         u8 query_bit;
  96 };
  97
  98 struct transaction {
  99         const u8 *wdata;
 100         u8 *rdata;
 101         unsigned short irq_count;
 102         u8 command;
 103         u8 wi;
 104         u8 ri;
 105         u8 wlen;
 106         u8 rlen;
 107         bool done;
 108 };
 109
 110 struct acpi_ec *boot_ec, *first_ec;
 111 EXPORT_SYMBOL(first_ec);
 112
 113 static int EC_FLAGS_MSI; /* Out-of-spec MSI controller */
 114 static int EC_FLAGS_VALIDATE_ECDT; /* ASUStec ECDTs need to be validated */
 115 static int EC_FLAGS_SKIP_DSDT_SCAN; /* Not all BIOS survive early DSDT scan */
 116
 117 /* --------------------------------------------------------------------------
 118                              Transaction Management
 119    -------------------------------------------------------------------------- */
 120
 121 static inline u8 acpi_ec_read_status(struct acpi_ec *ec)
 122 {
 123         u8 x = inb(ec->command_addr);
 124         pr_debug(PREFIX "---> status = 0x%2.2x\n", x);
 125         return x;
 126 }
 127
 128 static inline u8 acpi_ec_read_data(struct acpi_ec *ec)
 129 {
 130         u8 x = inb(ec->data_addr);
 131         pr_debug(PREFIX "---> data = 0x%2.2x\n", x);
 132         return x;
 133 }
 134
 135 static inline void acpi_ec_write_cmd(struct acpi_ec *ec, u8 command)
 136 {
 137         pr_debug(PREFIX "<--- command = 0x%2.2x\n", command);
 138         outb(command, ec->command_addr);
 139 }
 140
 141 static inline void acpi_ec_write_data(struct acpi_ec *ec, u8 data)
 142 {
 143         pr_debug(PREFIX "<--- data = 0x%2.2x\n", data);
 144         outb(data, ec->data_addr);
 145 }
 146
 147 static int ec_transaction_done(struct acpi_ec *ec)
 148 {
 149         unsigned long flags;
 150         int ret = 0;
 151         spin_lock_irqsave(&ec->curr_lock, flags);
 152         if (!ec->curr || ec->curr->done)
 153                 ret = 1;
 154         spin_unlock_irqrestore(&ec->curr_lock, flags);
 155         return ret;
 156 }
 157
 158 static void start_transaction(struct acpi_ec *ec)
 159 {
 160         ec->curr->irq_count = ec->curr->wi = ec->curr->ri = 0;
 161         ec->curr->done = false;
 162         acpi_ec_write_cmd(ec, ec->curr->command);
 163 }
 164
 165 static void advance_transaction(struct acpi_ec *ec, u8 status)
 166 {
 167         unsigned long flags;
 168         spin_lock_irqsave(&ec->curr_lock, flags);
 169         if (!ec->curr)
 170                 goto unlock;
 171         if (ec->curr->wlen > ec->curr->wi) {
 172                 if ((status & ACPI_EC_FLAG_IBF) == 0)
 173                         acpi_ec_write_data(ec,
 174                                 ec->curr->wdata[ec->curr->wi++]);
 175                 else
 176                         goto err;
 177         } else if (ec->curr->rlen > ec->curr->ri) {
 178                 if ((status & ACPI_EC_FLAG_OBF) == 1) {
 179                         ec->curr->rdata[ec->curr->ri++] = acpi_ec_read_data(ec);
 180                         if (ec->curr->rlen == ec->curr->ri)
 181                                 ec->curr->done = true;
 182                 } else
 183                         goto err;
 184         } else if (ec->curr->wlen == ec->curr->wi &&
 185                    (status & ACPI_EC_FLAG_IBF) == 0)
 186                 ec->curr->done = true;
 187         goto unlock;
 188 err:
 189         /* false interrupt, state didn't change */
 190         if (in_interrupt())
 191                 ++ec->curr->irq_count;
 192 unlock:
 193         spin_unlock_irqrestore(&ec->curr_lock, flags);
 194 }
 195
 196 static int acpi_ec_sync_query(struct acpi_ec *ec);
 197
 198 static int ec_check_sci_sync(struct acpi_ec *ec, u8 state)
 199 {
 200         if (state & ACPI_EC_FLAG_SCI) {
 201                 if (!test_and_set_bit(EC_FLAGS_QUERY_PENDING, &ec->flags))
 202                         return acpi_ec_sync_query(ec);
 203         }
 204         return 0;
 205 }
 206
 207 static int ec_poll(struct acpi_ec *ec)
 208 {
 209         unsigned long flags;
 210         int repeat = 2; /* number of command restarts */
 211         while (repeat--) {
 212                 unsigned long delay = jiffies +
 213                         msecs_to_jiffies(ACPI_EC_DELAY);
 214                 do {
 215                         /* don't sleep with disabled interrupts */
 216                         if (EC_FLAGS_MSI || irqs_disabled()) {
 217                                 udelay(ACPI_EC_MSI_UDELAY);
 218                                 if (ec_transaction_done(ec))
 219                                         return 0;
 220                         } else {
 221                                 if (wait_event_timeout(ec->wait,
 222                                                 ec_transaction_done(ec),
 223                                                 msecs_to_jiffies(1)))
 224                                         return 0;
 225                         }
 226                         advance_transaction(ec, acpi_ec_read_status(ec));
 227                 } while (time_before(jiffies, delay));
 228                 if (acpi_ec_read_status(ec) & ACPI_EC_FLAG_IBF)
 229                         break;
 230                 pr_debug(PREFIX "controller reset, restart transaction\n");
 231                 spin_lock_irqsave(&ec->curr_lock, flags);
 232                 start_transaction(ec);
 233                 spin_unlock_irqrestore(&ec->curr_lock, flags);
 234         }
 235         return -ETIME;
 236 }
 237
 238 static int acpi_ec_transaction_unlocked(struct acpi_ec *ec,
 239                                         struct transaction *t)
 240 {
 241         unsigned long tmp;
 242         int ret = 0;
 243         if (EC_FLAGS_MSI)
 244                 udelay(ACPI_EC_MSI_UDELAY);
 245         /* start transaction */
 246         spin_lock_irqsave(&ec->curr_lock, tmp);
 247         /* following two actions should be kept atomic */
 248         ec->curr = t;
 249         start_transaction(ec);
 250         if (ec->curr->command == ACPI_EC_COMMAND_QUERY)
 251                 clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags);
 252         spin_unlock_irqrestore(&ec->curr_lock, tmp);
 253         ret = ec_poll(ec);
 254         spin_lock_irqsave(&ec->curr_lock, tmp);
 255         ec->curr = NULL;
 256         spin_unlock_irqrestore(&ec->curr_lock, tmp);
 257         return ret;
 258 }
 259
 260 static int ec_check_ibf0(struct acpi_ec *ec)
 261 {
 262         u8 status = acpi_ec_read_status(ec);
 263         return (status & ACPI_EC_FLAG_IBF) == 0;
 264 }
 265
 266 static int ec_wait_ibf0(struct acpi_ec *ec)
 267 {
 268         unsigned long delay = jiffies + msecs_to_jiffies(ACPI_EC_DELAY);
 269         /* interrupt wait manually if GPE mode is not active */
 270         while (time_before(jiffies, delay))
 271                 if (wait_event_timeout(ec->wait, ec_check_ibf0(ec),
 272                                         msecs_to_jiffies(1)))
 273                         return 0;
 274         return -ETIME;
 275 }
 276
 277 static int acpi_ec_transaction(struct acpi_ec *ec, struct transaction *t)
 278 {
 279         int status;
 280         u32 glk;
 281         if (!ec || (!t) || (t->wlen && !t->wdata) || (t->rlen && !t->rdata))
 282                 return -EINVAL;
 283         if (t->rdata)
 284                 memset(t->rdata, 0, t->rlen);
 285         mutex_lock(&ec->lock);
 286         if (test_bit(EC_FLAGS_BLOCKED, &ec->flags)) {
 287                 status = -EINVAL;
 288                 goto unlock;
 289         }
 290         if (ec->global_lock) {
 291                 status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk);
 292                 if (ACPI_FAILURE(status)) {
 293                         status = -ENODEV;
 294                         goto unlock;
 295                 }
 296         }
 297         if (ec_wait_ibf0(ec)) {
 298                 pr_err(PREFIX "input buffer is not empty, "
 299                                 "aborting transaction\n");
 300                 status = -ETIME;
 301                 goto end;
 302         }
 303         pr_debug(PREFIX "transaction start\n");
 304         /* disable GPE during transaction if storm is detected */
 305         if (test_bit(EC_FLAGS_GPE_STORM, &ec->flags)) {
 306                 /* It has to be disabled, so that it doesn't trigger. */
 307                 acpi_disable_gpe(NULL, ec->gpe);
 308         }
 309
 310         status = acpi_ec_transaction_unlocked(ec, t);
 311
 312         /* check if we received SCI during transaction */
 313         ec_check_sci_sync(ec, acpi_ec_read_status(ec));
 314         if (test_bit(EC_FLAGS_GPE_STORM, &ec->flags)) {
 315                 msleep(1);
 316                 /* It is safe to enable the GPE outside of the transaction. */
 317                 acpi_enable_gpe(NULL, ec->gpe);
 318         } else if (t->irq_count > ACPI_EC_STORM_THRESHOLD) {
 319                 pr_info(PREFIX "GPE storm detected, "
 320                         "transactions will use polling mode\n");
 321                 set_bit(EC_FLAGS_GPE_STORM, &ec->flags);
 322         }
 323         pr_debug(PREFIX "transaction end\n");
 324 end:
 325         if (ec->global_lock)
 326                 acpi_release_global_lock(glk);
 327 unlock:
 328         mutex_unlock(&ec->lock);
 329         return status;
 330 }
 331
 332 static int acpi_ec_burst_enable(struct acpi_ec *ec)
 333 {
 334         u8 d;
 335         struct transaction t = {.command = ACPI_EC_BURST_ENABLE,
 336                                 .wdata = NULL, .rdata = &d,
 337                                 .wlen = 0, .rlen = 1};
 338
 339         return acpi_ec_transaction(ec, &t);
 340 }
 341
 342 static int acpi_ec_burst_disable(struct acpi_ec *ec)
 343 {
 344         struct transaction t = {.command = ACPI_EC_BURST_DISABLE,
 345                                 .wdata = NULL, .rdata = NULL,
 346                                 .wlen = 0, .rlen = 0};
 347
 348         return (acpi_ec_read_status(ec) & ACPI_EC_FLAG_BURST) ?
 349                                 acpi_ec_transaction(ec, &t) : 0;
 350 }
 351
 352 static int acpi_ec_read(struct acpi_ec *ec, u8 address, u8 * data)
 353 {
 354         int result;
 355         u8 d;
 356         struct transaction t = {.command = ACPI_EC_COMMAND_READ,
 357                                 .wdata = &address, .rdata = &d,
 358                                 .wlen = 1, .rlen = 1};
 359
 360         result = acpi_ec_transaction(ec, &t);
 361         *data = d;
 362         return result;
 363 }
 364
 365 static int acpi_ec_write(struct acpi_ec *ec, u8 address, u8 data)
 366 {
 367         u8 wdata[2] = { address, data };
 368         struct transaction t = {.command = ACPI_EC_COMMAND_WRITE,
 369                                 .wdata = wdata, .rdata = NULL,
 370                                 .wlen = 2, .rlen = 0};
 371
 372         return acpi_ec_transaction(ec, &t);
 373 }
 374
 375 /*
 376  * Externally callable EC access functions. For now, assume 1 EC only
 377  */
 378 int ec_burst_enable(void)
 379 {
 380         if (!first_ec)
 381                 return -ENODEV;
 382         return acpi_ec_burst_enable(first_ec);
 383 }
 384
 385 EXPORT_SYMBOL(ec_burst_enable);
 386
 387 int ec_burst_disable(void)
 388 {
 389         if (!first_ec)
 390                 return -ENODEV;
 391         return acpi_ec_burst_disable(first_ec);
 392 }
 393
 394 EXPORT_SYMBOL(ec_burst_disable);
 395
 396 int ec_read(u8 addr, u8 * val)
 397 {
 398         int err;
 399         u8 temp_data;
 400
 401         if (!first_ec)
 402                 return -ENODEV;
 403
 404         err = acpi_ec_read(first_ec, addr, &temp_data);
 405
 406         if (!err) {
 407                 *val = temp_data;
 408                 return 0;
 409         } else
 410                 return err;
 411 }
 412
 413 EXPORT_SYMBOL(ec_read);
 414
 415 int ec_write(u8 addr, u8 val)
 416 {
 417         int err;
 418
 419         if (!first_ec)
 420                 return -ENODEV;
 421
 422         err = acpi_ec_write(first_ec, addr, val);
 423
 424         return err;
 425 }
 426
 427 EXPORT_SYMBOL(ec_write);
 428
 429 int ec_transaction(u8 command,
 430                    const u8 * wdata, unsigned wdata_len,
 431                    u8 * rdata, unsigned rdata_len,
 432                    int force_poll)
 433 {
 434         struct transaction t = {.command = command,
 435                                 .wdata = wdata, .rdata = rdata,
 436                                 .wlen = wdata_len, .rlen = rdata_len};
 437         if (!first_ec)
 438                 return -ENODEV;
 439
 440         return acpi_ec_transaction(first_ec, &t);
 441 }
 442
 443 EXPORT_SYMBOL(ec_transaction);
 444
 445 void acpi_ec_block_transactions(void)
 446 {
 447         struct acpi_ec *ec = first_ec;
 448
 449         if (!ec)
 450                 return;
 451
 452         mutex_lock(&ec->lock);
 453         /* Prevent transactions from being carried out */
 454         set_bit(EC_FLAGS_BLOCKED, &ec->flags);
 455         mutex_unlock(&ec->lock);
 456 }
 457
 458 void acpi_ec_unblock_transactions(void)
 459 {
 460         struct acpi_ec *ec = first_ec;
 461
 462         if (!ec)
 463                 return;
 464
 465         mutex_lock(&ec->lock);
 466         /* Allow transactions to be carried out again */
 467         clear_bit(EC_FLAGS_BLOCKED, &ec->flags);
 468         mutex_unlock(&ec->lock);
 469 }
 470
 471 void acpi_ec_unblock_transactions_early(void)
 472 {
 473         /*
 474          * Allow transactions to happen again (this function is called from
 475          * atomic context during wakeup, so we don't need to acquire the mutex).
 476          */
 477         if (first_ec)
 478                 clear_bit(EC_FLAGS_BLOCKED, &first_ec->flags);
 479 }
 480
 481 static int acpi_ec_query_unlocked(struct acpi_ec *ec, u8 * data)
 482 {
 483         int result;
 484         u8 d;
 485         struct transaction t = {.command = ACPI_EC_COMMAND_QUERY,
 486                                 .wdata = NULL, .rdata = &d,
 487                                 .wlen = 0, .rlen = 1};
 488         if (!ec || !data)
 489                 return -EINVAL;
 490         /*
 491          * Query the EC to find out which _Qxx method we need to evaluate.
 492          * Note that successful completion of the query causes the ACPI_EC_SCI
 493          * bit to be cleared (and thus clearing the interrupt source).
 494          */
 495         result = acpi_ec_transaction_unlocked(ec, &t);
 496         if (result)
 497                 return result;
 498         if (!d)
 499                 return -ENODATA;
 500         *data = d;
 501         return 0;
 502 }
 503
 504 /* --------------------------------------------------------------------------
 505                                 Event Management
 506    -------------------------------------------------------------------------- */
 507 int acpi_ec_add_query_handler(struct acpi_ec *ec, u8 query_bit,
 508                               acpi_handle handle, acpi_ec_query_func func,
 509                               void *data)
 510 {
 511         struct acpi_ec_query_handler *handler =
 512             kzalloc(sizeof(struct acpi_ec_query_handler), GFP_KERNEL);
 513         if (!handler)
 514                 return -ENOMEM;
 515
 516         handler->query_bit = query_bit;
 517         handler->handle = handle;
 518         handler->func = func;
 519         handler->data = data;
 520         mutex_lock(&ec->lock);
 521         list_add(&handler->node, &ec->list);
 522         mutex_unlock(&ec->lock);
 523         return 0;
 524 }
 525
 526 EXPORT_SYMBOL_GPL(acpi_ec_add_query_handler);
 527
 528 void acpi_ec_remove_query_handler(struct acpi_ec *ec, u8 query_bit)
 529 {
 530         struct acpi_ec_query_handler *handler, *tmp;
 531         mutex_lock(&ec->lock);
 532         list_for_each_entry_safe(handler, tmp, &ec->list, node) {
 533                 if (query_bit == handler->query_bit) {
 534                         list_del(&handler->node);
 535                         kfree(handler);
 536                 }
 537         }
 538         mutex_unlock(&ec->lock);
 539 }
 540
 541 EXPORT_SYMBOL_GPL(acpi_ec_remove_query_handler);
 542
 543 static void acpi_ec_run(void *cxt)
 544 {
 545         struct acpi_ec_query_handler *handler = cxt;
 546         if (!handler)
 547                 return;
 548         pr_debug(PREFIX "start query execution\n");
 549         if (handler->func)
 550                 handler->func(handler->data);
 551         else if (handler->handle)
 552                 acpi_evaluate_object(handler->handle, NULL, NULL, NULL);
 553         pr_debug(PREFIX "stop query execution\n");
 554         kfree(handler);
 555 }
 556
 557 static int acpi_ec_sync_query(struct acpi_ec *ec)
 558 {
 559         u8 value = 0;
 560         int status;
 561         struct acpi_ec_query_handler *handler, *copy;
 562         if ((status = acpi_ec_query_unlocked(ec, &value)))
 563                 return status;
 564         list_for_each_entry(handler, &ec->list, node) {
 565                 if (value == handler->query_bit) {
 566                         /* have custom handler for this bit */
 567                         copy = kmalloc(sizeof(*handler), GFP_KERNEL);
 568                         if (!copy)
 569                                 return -ENOMEM;
 570                         memcpy(copy, handler, sizeof(*copy));
 571                         pr_debug(PREFIX "push query execution (0x%2x) on queue\n", value);
 572                         return acpi_os_execute((copy->func) ?
 573                                 OSL_NOTIFY_HANDLER : OSL_GPE_HANDLER,
 574                                 acpi_ec_run, copy);
 575                 }
 576         }
 577         return 0;
 578 }
 579
 580 static void acpi_ec_gpe_query(void *ec_cxt)
 581 {
 582         struct acpi_ec *ec = ec_cxt;
 583         if (!ec)
 584                 return;
 585         mutex_lock(&ec->lock);
 586         acpi_ec_sync_query(ec);
 587         mutex_unlock(&ec->lock);
 588 }
 589
 590 static void acpi_ec_gpe_query(void *ec_cxt);
 591
 592 static int ec_check_sci(struct acpi_ec *ec, u8 state)
 593 {
 594         if (state & ACPI_EC_FLAG_SCI) {
 595                 if (!test_and_set_bit(EC_FLAGS_QUERY_PENDING, &ec->flags)) {
 596                         pr_debug(PREFIX "push gpe query to the queue\n");
 597                         return acpi_os_execute(OSL_NOTIFY_HANDLER,
 598                                 acpi_ec_gpe_query, ec);
 599                 }
 600         }
 601         return 0;
 602 }
 603
 604 static u32 acpi_ec_gpe_handler(void *data)
 605 {
 606         struct acpi_ec *ec = data;
 607
 608         pr_debug(PREFIX "~~~> interrupt\n");
 609
 610         advance_transaction(ec, acpi_ec_read_status(ec));
 611         if (ec_transaction_done(ec) &&
 612             (acpi_ec_read_status(ec) & ACPI_EC_FLAG_IBF) == 0) {
 613                 wake_up(&ec->wait);
 614                 ec_check_sci(ec, acpi_ec_read_status(ec));
 615         }
 616         return ACPI_INTERRUPT_HANDLED;
 617 }
 618
 619 /* --------------------------------------------------------------------------
 620                              Address Space Management
 621    -------------------------------------------------------------------------- */
 622
 623 static acpi_status
 624 acpi_ec_space_handler(u32 function, acpi_physical_address address,
 625                       u32 bits, u64 *value64,
 626                       void *handler_context, void *region_context)
 627 {
 628         struct acpi_ec *ec = handler_context;
 629         int result = 0, i, bytes = bits / 8;
 630         u8 *value = (u8 *)value64;
 631
 632         if ((address > 0xFF) || !value || !handler_context)
 633                 return AE_BAD_PARAMETER;
 634
 635         if (function != ACPI_READ && function != ACPI_WRITE)
 636                 return AE_BAD_PARAMETER;
 637
 638         if (EC_FLAGS_MSI || bits > 8)
 639                 acpi_ec_burst_enable(ec);
 640
 641         for (i = 0; i < bytes; ++i, ++address, ++value)
 642                 result = (function == ACPI_READ) ?
 643                         acpi_ec_read(ec, address, value) :
 644                         acpi_ec_write(ec, address, *value);
 645
 646         if (EC_FLAGS_MSI || bits > 8)
 647                 acpi_ec_burst_disable(ec);
 648
 649         switch (result) {
 650         case -EINVAL:
 651                 return AE_BAD_PARAMETER;
 652                 break;
 653         case -ENODEV:
 654                 return AE_NOT_FOUND;
 655                 break;
 656         case -ETIME:
 657                 return AE_TIME;
 658                 break;
 659         default:
 660                 return AE_OK;
 661         }
 662 }
 663
 664 /* --------------------------------------------------------------------------
 665                                Driver Interface
 666    -------------------------------------------------------------------------- */
 667 static acpi_status
 668 ec_parse_io_ports(struct acpi_resource *resource, void *context);
 669
 670 static struct acpi_ec *make_acpi_ec(void)
 671 {
 672         struct acpi_ec *ec = kzalloc(sizeof(struct acpi_ec), GFP_KERNEL);
 673         if (!ec)
 674                 return NULL;
 675         ec->flags = 1 << EC_FLAGS_QUERY_PENDING;
 676         mutex_init(&ec->lock);
 677         init_waitqueue_head(&ec->wait);
 678         INIT_LIST_HEAD(&ec->list);
 679         spin_lock_init(&ec->curr_lock);
 680         return ec;
 681 }
 682
 683 static acpi_status
 684 acpi_ec_register_query_methods(acpi_handle handle, u32 level,
 685                                void *context, void **return_value)
 686 {
 687         char node_name[5];
 688         struct acpi_buffer buffer = { sizeof(node_name), node_name };
 689         struct acpi_ec *ec = context;
 690         int value = 0;
 691         acpi_status status;
 692
 693         status = acpi_get_name(handle, ACPI_SINGLE_NAME, &buffer);
 694
 695         if (ACPI_SUCCESS(status) && sscanf(node_name, "_Q%x", &value) == 1) {
 696                 acpi_ec_add_query_handler(ec, value, handle, NULL, NULL);
 697         }
 698         return AE_OK;
 699 }
 700
 701 static acpi_status
 702 ec_parse_device(acpi_handle handle, u32 Level, void *context, void **retval)
 703 {
 704         acpi_status status;
 705         unsigned long long tmp = 0;
 706
 707         struct acpi_ec *ec = context;
 708
 709         /* clear addr values, ec_parse_io_ports depend on it */
 710         ec->command_addr = ec->data_addr = 0;
 711
 712         status = acpi_walk_resources(handle, METHOD_NAME__CRS,
 713                                      ec_parse_io_ports, ec);
 714         if (ACPI_FAILURE(status))
 715                 return status;
 716
 717         /* Get GPE bit assignment (EC events). */
 718         /* TODO: Add support for _GPE returning a package */
 719         status = acpi_evaluate_integer(handle, "_GPE", NULL, &tmp);
 720         if (ACPI_FAILURE(status))
 721                 return status;
 722         ec->gpe = tmp;
 723         /* Use the global lock for all EC transactions? */
 724         tmp = 0;
 725         acpi_evaluate_integer(handle, "_GLK", NULL, &tmp);
 726         ec->global_lock = tmp;
 727         ec->handle = handle;
 728         return AE_CTRL_TERMINATE;
 729 }
 730
 731 static int ec_install_handlers(struct acpi_ec *ec)
 732 {
 733         acpi_status status;
 734         if (test_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags))
 735                 return 0;
 736         status = acpi_install_gpe_handler(NULL, ec->gpe,
 737                                   ACPI_GPE_EDGE_TRIGGERED,
 738                                   &acpi_ec_gpe_handler, ec);
 739         if (ACPI_FAILURE(status))
 740                 return -ENODEV;
 741
 742         acpi_enable_gpe(NULL, ec->gpe);
 743         status = acpi_install_address_space_handler(ec->handle,
 744                                                     ACPI_ADR_SPACE_EC,
 745                                                     &acpi_ec_space_handler,
 746                                                     NULL, ec);
 747         if (ACPI_FAILURE(status)) {
 748                 if (status == AE_NOT_FOUND) {
 749                         /*
 750                          * Maybe OS fails in evaluating the _REG object.
 751                          * The AE_NOT_FOUND error will be ignored and OS
 752                          * continue to initialize EC.
 753                          */
 754                         printk(KERN_ERR "Fail in evaluating the _REG object"
 755                                 " of EC device. Broken bios is suspected.\n");
 756                 } else {
 757                         acpi_remove_gpe_handler(NULL, ec->gpe,
 758                                 &acpi_ec_gpe_handler);
 759                         acpi_disable_gpe(NULL, ec->gpe);
 760                         return -ENODEV;
 761                 }
 762         }
 763
 764         set_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags);
 765         return 0;
 766 }
 767
 768 static void ec_remove_handlers(struct acpi_ec *ec)
 769 {
 770         acpi_disable_gpe(NULL, ec->gpe);
 771         if (ACPI_FAILURE(acpi_remove_address_space_handler(ec->handle,
 772                                 ACPI_ADR_SPACE_EC, &acpi_ec_space_handler)))
 773                 pr_err(PREFIX "failed to remove space handler\n");
 774         if (ACPI_FAILURE(acpi_remove_gpe_handler(NULL, ec->gpe,
 775                                 &acpi_ec_gpe_handler)))
 776                 pr_err(PREFIX "failed to remove gpe handler\n");
 777         clear_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags);
 778 }
 779
 780 static int acpi_ec_add(struct acpi_device *device)
 781 {
 782         struct acpi_ec *ec = NULL;
 783         int ret;
 784
 785         strcpy(acpi_device_name(device), ACPI_EC_DEVICE_NAME);
 786         strcpy(acpi_device_class(device), ACPI_EC_CLASS);
 787
 788         /* Check for boot EC */
 789         if (boot_ec &&
 790             (boot_ec->handle == device->handle ||
 791              boot_ec->handle == ACPI_ROOT_OBJECT)) {
 792                 ec = boot_ec;
 793                 boot_ec = NULL;
 794         } else {
 795                 ec = make_acpi_ec();
 796                 if (!ec)
 797                         return -ENOMEM;
 798         }
 799         if (ec_parse_device(device->handle, 0, ec, NULL) !=
 800                 AE_CTRL_TERMINATE) {
 801                         kfree(ec);
 802                         return -EINVAL;
 803         }
 804
 805         ec->handle = device->handle;
 806
 807         /* Find and register all query methods */
 808         acpi_walk_namespace(ACPI_TYPE_METHOD, ec->handle, 1,
 809                             acpi_ec_register_query_methods, NULL, ec, NULL);
 810
 811         if (!first_ec)
 812                 first_ec = ec;
 813         device->driver_data = ec;
 814
 815         WARN(!request_region(ec->data_addr, 1, "EC data"),
 816              "Could not request EC data io port 0x%lx", ec->data_addr);
 817         WARN(!request_region(ec->command_addr, 1, "EC cmd"),
 818              "Could not request EC cmd io port 0x%lx", ec->command_addr);
 819
 820         pr_info(PREFIX "GPE = 0x%lx, I/O: command/status = 0x%lx, data = 0x%lx\n",
 821                           ec->gpe, ec->command_addr, ec->data_addr);
 822
 823         ret = ec_install_handlers(ec);
 824
 825         /* EC is fully operational, allow queries */
 826         clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags);
 827         return ret;
 828 }
 829
 830 static int acpi_ec_remove(struct acpi_device *device, int type)
 831 {
 832         struct acpi_ec *ec;
 833         struct acpi_ec_query_handler *handler, *tmp;
 834
 835         if (!device)
 836                 return -EINVAL;
 837
 838         ec = acpi_driver_data(device);
 839         ec_remove_handlers(ec);
 840         mutex_lock(&ec->lock);
 841         list_for_each_entry_safe(handler, tmp, &ec->list, node) {
 842                 list_del(&handler->node);
 843                 kfree(handler);
 844         }
 845         mutex_unlock(&ec->lock);
 846         release_region(ec->data_addr, 1);
 847         release_region(ec->command_addr, 1);
 848         device->driver_data = NULL;
 849         if (ec == first_ec)
 850                 first_ec = NULL;
 851         kfree(ec);
 852         return 0;
 853 }
 854
 855 static acpi_status
 856 ec_parse_io_ports(struct acpi_resource *resource, void *context)
 857 {
 858         struct acpi_ec *ec = context;
 859
 860         if (resource->type != ACPI_RESOURCE_TYPE_IO)
 861                 return AE_OK;
 862
 863         /*
 864          * The first address region returned is the data port, and
 865          * the second address region returned is the status/command
 866          * port.
 867          */
 868         if (ec->data_addr == 0)
 869                 ec->data_addr = resource->data.io.minimum;
 870         else if (ec->command_addr == 0)
 871                 ec->command_addr = resource->data.io.minimum;
 872         else
 873                 return AE_CTRL_TERMINATE;
 874
 875         return AE_OK;
 876 }
 877
 878 int __init acpi_boot_ec_enable(void)
 879 {
 880         if (!boot_ec || test_bit(EC_FLAGS_HANDLERS_INSTALLED, &boot_ec->flags))
 881                 return 0;
 882         if (!ec_install_handlers(boot_ec)) {
 883                 first_ec = boot_ec;
 884                 return 0;
 885         }
 886         return -EFAULT;
 887 }
 888
 889 static const struct acpi_device_id ec_device_ids[] = {
 890         {"PNP0C09", 0},
 891         {"", 0},
 892 };
 893
 894 /* Some BIOS do not survive early DSDT scan, skip it */
 895 static int ec_skip_dsdt_scan(const struct dmi_system_id *id)
 896 {
 897         EC_FLAGS_SKIP_DSDT_SCAN = 1;
 898         return 0;
 899 }
 900
 901 /* ASUStek often supplies us with broken ECDT, validate it */
 902 static int ec_validate_ecdt(const struct dmi_system_id *id)
 903 {
 904         EC_FLAGS_VALIDATE_ECDT = 1;
 905         return 0;
 906 }
 907
 908 /* MSI EC needs special treatment, enable it */
 909 static int ec_flag_msi(const struct dmi_system_id *id)
 910 {
 911         printk(KERN_DEBUG PREFIX "Detected MSI hardware, enabling workarounds.\n");
 912         EC_FLAGS_MSI = 1;
 913         EC_FLAGS_VALIDATE_ECDT = 1;
 914         return 0;
 915 }
 916
 917 static struct dmi_system_id __initdata ec_dmi_table[] = {
 918         {
 919         ec_skip_dsdt_scan, "Compal JFL92", {
 920         DMI_MATCH(DMI_BIOS_VENDOR, "COMPAL"),
 921         DMI_MATCH(DMI_BOARD_NAME, "JFL92") }, NULL},
 922         {
 923         ec_flag_msi, "MSI hardware", {
 924         DMI_MATCH(DMI_BIOS_VENDOR, "Micro-Star")}, NULL},
 925         {
 926         ec_flag_msi, "MSI hardware", {
 927         DMI_MATCH(DMI_SYS_VENDOR, "Micro-Star")}, NULL},
 928         {
 929         ec_flag_msi, "MSI hardware", {
 930         DMI_MATCH(DMI_CHASSIS_VENDOR, "MICRO-Star")}, NULL},
 931         {
 932         ec_validate_ecdt, "ASUS hardware", {
 933         DMI_MATCH(DMI_BIOS_VENDOR, "ASUS") }, NULL},
 934         {},
 935 };
 936
 937
 938 int __init acpi_ec_ecdt_probe(void)
 939 {
 940         acpi_status status;
 941         struct acpi_ec *saved_ec = NULL;
 942         struct acpi_table_ecdt *ecdt_ptr;
 943
 944         boot_ec = make_acpi_ec();
 945         if (!boot_ec)
 946                 return -ENOMEM;
 947         /*
 948          * Generate a boot ec context
 949          */
 950         dmi_check_system(ec_dmi_table);
 951         status = acpi_get_table(ACPI_SIG_ECDT, 1,
 952                                 (struct acpi_table_header **)&ecdt_ptr);
 953         if (ACPI_SUCCESS(status)) {
 954                 pr_info(PREFIX "EC description table is found, configuring boot EC\n");
 955                 boot_ec->command_addr = ecdt_ptr->control.address;
 956                 boot_ec->data_addr = ecdt_ptr->data.address;
 957                 boot_ec->gpe = ecdt_ptr->gpe;
 958                 boot_ec->handle = ACPI_ROOT_OBJECT;
 959                 acpi_get_handle(ACPI_ROOT_OBJECT, ecdt_ptr->id, &boot_ec->handle);
 960                 /* Don't trust ECDT, which comes from ASUSTek */
 961                 if (!EC_FLAGS_VALIDATE_ECDT)
 962                         goto install;
 963                 saved_ec = kmemdup(boot_ec, sizeof(struct acpi_ec), GFP_KERNEL);
 964                 if (!saved_ec)
 965                         return -ENOMEM;
 966         /* fall through */
 967         }
 968
 969         if (EC_FLAGS_SKIP_DSDT_SCAN)
 970                 return -ENODEV;
 971
 972         /* This workaround is needed only on some broken machines,
 973          * which require early EC, but fail to provide ECDT */
 974         printk(KERN_DEBUG PREFIX "Look up EC in DSDT\n");
 975         status = acpi_get_devices(ec_device_ids[0].id, ec_parse_device,
 976                                         boot_ec, NULL);
 977         /* Check that acpi_get_devices actually find something */
 978         if (ACPI_FAILURE(status) || !boot_ec->handle)
 979                 goto error;
 980         if (saved_ec) {
 981                 /* try to find good ECDT from ASUSTek */
 982                 if (saved_ec->command_addr != boot_ec->command_addr ||
 983                     saved_ec->data_addr != boot_ec->data_addr ||
 984                     saved_ec->gpe != boot_ec->gpe ||
 985                     saved_ec->handle != boot_ec->handle)
 986                         pr_info(PREFIX "ASUSTek keeps feeding us with broken "
 987                         "ECDT tables, which are very hard to workaround. "
 988                         "Trying to use DSDT EC info instead. Please send "
 989                         "output of acpidump to linux-acpi@vger.kernel.org\n");
 990                 kfree(saved_ec);
 991                 saved_ec = NULL;
 992         } else {
 993                 /* We really need to limit this workaround, the only ASUS,
 994                 * which needs it, has fake EC._INI method, so use it as flag.
 995                 * Keep boot_ec struct as it will be needed soon.
 996                 */
 997                 acpi_handle dummy;
 998                 if (!dmi_name_in_vendors("ASUS") ||
 999                     ACPI_FAILURE(acpi_get_handle(boot_ec->handle, "_INI",
1000                                                         &dummy)))
1001                         return -ENODEV;
1002         }
1003 install:
1004         if (!ec_install_handlers(boot_ec)) {
1005                 first_ec = boot_ec;
1006                 return 0;
1007         }
1008 error:
1009         kfree(boot_ec);
1010         boot_ec = NULL;
1011         return -ENODEV;
1012 }
1013
1014 static struct acpi_driver acpi_ec_driver = {
1015         .name = "ec",
1016         .class = ACPI_EC_CLASS,
1017         .ids = ec_device_ids,
1018         .ops = {
1019                 .add = acpi_ec_add,
1020                 .remove = acpi_ec_remove,
1021                 },
1022 };
1023
1024 int __init acpi_ec_init(void)
1025 {
1026         int result = 0;
1027
1028         /* Now register the driver for the EC */
1029         result = acpi_bus_register_driver(&acpi_ec_driver);
1030         if (result < 0)
1031                 return -ENODEV;
1032
1033         return result;
1034 }
1035
1036 /* EC driver currently not unloadable */
1037 #if 0
1038 static void __exit acpi_ec_exit(void)
1039 {
1040
1041         acpi_bus_unregister_driver(&acpi_ec_driver);
1042         return;
1043 }
1044 #endif  /* 0 */