linux/drivers/acpi/ec.c
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   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 */
  62enum 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#define ACPI_EC_STORM_THRESHOLD 8       /* number of false interrupts
  75                                           per one transaction */
  76
  77enum {
  78        EC_FLAGS_QUERY_PENDING,         /* Query is pending */
  79        EC_FLAGS_GPE_STORM,             /* GPE storm detected */
  80        EC_FLAGS_HANDLERS_INSTALLED,    /* Handlers for GPE and
  81                                         * OpReg are installed */
  82        EC_FLAGS_BLOCKED,               /* Transactions are blocked */
  83};
  84
  85/* ec.c is compiled in acpi namespace so this shows up as acpi.ec_delay param */
  86static unsigned int ec_delay __read_mostly = ACPI_EC_DELAY;
  87module_param(ec_delay, uint, 0644);
  88MODULE_PARM_DESC(ec_delay, "Timeout(ms) waited until an EC command completes");
  89
  90/* If we find an EC via the ECDT, we need to keep a ptr to its context */
  91/* External interfaces use first EC only, so remember */
  92typedef int (*acpi_ec_query_func) (void *data);
  93
  94struct acpi_ec_query_handler {
  95        struct list_head node;
  96        acpi_ec_query_func func;
  97        acpi_handle handle;
  98        void *data;
  99        u8 query_bit;
 100};
 101
 102struct transaction {
 103        const u8 *wdata;
 104        u8 *rdata;
 105        unsigned short irq_count;
 106        u8 command;
 107        u8 wi;
 108        u8 ri;
 109        u8 wlen;
 110        u8 rlen;
 111        bool done;
 112};
 113
 114struct acpi_ec *boot_ec, *first_ec;
 115EXPORT_SYMBOL(first_ec);
 116
 117static int EC_FLAGS_MSI; /* Out-of-spec MSI controller */
 118static int EC_FLAGS_VALIDATE_ECDT; /* ASUStec ECDTs need to be validated */
 119static int EC_FLAGS_SKIP_DSDT_SCAN; /* Not all BIOS survive early DSDT scan */
 120
 121/* --------------------------------------------------------------------------
 122                             Transaction Management
 123   -------------------------------------------------------------------------- */
 124
 125static inline u8 acpi_ec_read_status(struct acpi_ec *ec)
 126{
 127        u8 x = inb(ec->command_addr);
 128        pr_debug(PREFIX "---> status = 0x%2.2x\n", x);
 129        return x;
 130}
 131
 132static inline u8 acpi_ec_read_data(struct acpi_ec *ec)
 133{
 134        u8 x = inb(ec->data_addr);
 135        pr_debug(PREFIX "---> data = 0x%2.2x\n", x);
 136        return x;
 137}
 138
 139static inline void acpi_ec_write_cmd(struct acpi_ec *ec, u8 command)
 140{
 141        pr_debug(PREFIX "<--- command = 0x%2.2x\n", command);
 142        outb(command, ec->command_addr);
 143}
 144
 145static inline void acpi_ec_write_data(struct acpi_ec *ec, u8 data)
 146{
 147        pr_debug(PREFIX "<--- data = 0x%2.2x\n", data);
 148        outb(data, ec->data_addr);
 149}
 150
 151static int ec_transaction_done(struct acpi_ec *ec)
 152{
 153        unsigned long flags;
 154        int ret = 0;
 155        spin_lock_irqsave(&ec->curr_lock, flags);
 156        if (!ec->curr || ec->curr->done)
 157                ret = 1;
 158        spin_unlock_irqrestore(&ec->curr_lock, flags);
 159        return ret;
 160}
 161
 162static void start_transaction(struct acpi_ec *ec)
 163{
 164        ec->curr->irq_count = ec->curr->wi = ec->curr->ri = 0;
 165        ec->curr->done = false;
 166        acpi_ec_write_cmd(ec, ec->curr->command);
 167}
 168
 169static void advance_transaction(struct acpi_ec *ec, u8 status)
 170{
 171        unsigned long flags;
 172        spin_lock_irqsave(&ec->curr_lock, flags);
 173        if (!ec->curr)
 174                goto unlock;
 175        if (ec->curr->wlen > ec->curr->wi) {
 176                if ((status & ACPI_EC_FLAG_IBF) == 0)
 177                        acpi_ec_write_data(ec,
 178                                ec->curr->wdata[ec->curr->wi++]);
 179                else
 180                        goto err;
 181        } else if (ec->curr->rlen > ec->curr->ri) {
 182                if ((status & ACPI_EC_FLAG_OBF) == 1) {
 183                        ec->curr->rdata[ec->curr->ri++] = acpi_ec_read_data(ec);
 184                        if (ec->curr->rlen == ec->curr->ri)
 185                                ec->curr->done = true;
 186                } else
 187                        goto err;
 188        } else if (ec->curr->wlen == ec->curr->wi &&
 189                   (status & ACPI_EC_FLAG_IBF) == 0)
 190                ec->curr->done = true;
 191        goto unlock;
 192err:
 193        /* false interrupt, state didn't change */
 194        if (in_interrupt())
 195                ++ec->curr->irq_count;
 196unlock:
 197        spin_unlock_irqrestore(&ec->curr_lock, flags);
 198}
 199
 200static int acpi_ec_sync_query(struct acpi_ec *ec);
 201
 202static int ec_check_sci_sync(struct acpi_ec *ec, u8 state)
 203{
 204        if (state & ACPI_EC_FLAG_SCI) {
 205                if (!test_and_set_bit(EC_FLAGS_QUERY_PENDING, &ec->flags))
 206                        return acpi_ec_sync_query(ec);
 207        }
 208        return 0;
 209}
 210
 211static int ec_poll(struct acpi_ec *ec)
 212{
 213        unsigned long flags;
 214        int repeat = 2; /* number of command restarts */
 215        while (repeat--) {
 216                unsigned long delay = jiffies +
 217                        msecs_to_jiffies(ec_delay);
 218                do {
 219                        /* don't sleep with disabled interrupts */
 220                        if (EC_FLAGS_MSI || irqs_disabled()) {
 221                                udelay(ACPI_EC_MSI_UDELAY);
 222                                if (ec_transaction_done(ec))
 223                                        return 0;
 224                        } else {
 225                                if (wait_event_timeout(ec->wait,
 226                                                ec_transaction_done(ec),
 227                                                msecs_to_jiffies(1)))
 228                                        return 0;
 229                        }
 230                        advance_transaction(ec, acpi_ec_read_status(ec));
 231                } while (time_before(jiffies, delay));
 232                if (acpi_ec_read_status(ec) & ACPI_EC_FLAG_IBF)
 233                        break;
 234                pr_debug(PREFIX "controller reset, restart transaction\n");
 235                spin_lock_irqsave(&ec->curr_lock, flags);
 236                start_transaction(ec);
 237                spin_unlock_irqrestore(&ec->curr_lock, flags);
 238        }
 239        return -ETIME;
 240}
 241
 242static int acpi_ec_transaction_unlocked(struct acpi_ec *ec,
 243                                        struct transaction *t)
 244{
 245        unsigned long tmp;
 246        int ret = 0;
 247        if (EC_FLAGS_MSI)
 248                udelay(ACPI_EC_MSI_UDELAY);
 249        /* start transaction */
 250        spin_lock_irqsave(&ec->curr_lock, tmp);
 251        /* following two actions should be kept atomic */
 252        ec->curr = t;
 253        start_transaction(ec);
 254        if (ec->curr->command == ACPI_EC_COMMAND_QUERY)
 255                clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags);
 256        spin_unlock_irqrestore(&ec->curr_lock, tmp);
 257        ret = ec_poll(ec);
 258        spin_lock_irqsave(&ec->curr_lock, tmp);
 259        ec->curr = NULL;
 260        spin_unlock_irqrestore(&ec->curr_lock, tmp);
 261        return ret;
 262}
 263
 264static int ec_check_ibf0(struct acpi_ec *ec)
 265{
 266        u8 status = acpi_ec_read_status(ec);
 267        return (status & ACPI_EC_FLAG_IBF) == 0;
 268}
 269
 270static int ec_wait_ibf0(struct acpi_ec *ec)
 271{
 272        unsigned long delay = jiffies + msecs_to_jiffies(ec_delay);
 273        /* interrupt wait manually if GPE mode is not active */
 274        while (time_before(jiffies, delay))
 275                if (wait_event_timeout(ec->wait, ec_check_ibf0(ec),
 276                                        msecs_to_jiffies(1)))
 277                        return 0;
 278        return -ETIME;
 279}
 280
 281static int acpi_ec_transaction(struct acpi_ec *ec, struct transaction *t)
 282{
 283        int status;
 284        u32 glk;
 285        if (!ec || (!t) || (t->wlen && !t->wdata) || (t->rlen && !t->rdata))
 286                return -EINVAL;
 287        if (t->rdata)
 288                memset(t->rdata, 0, t->rlen);
 289        mutex_lock(&ec->lock);
 290        if (test_bit(EC_FLAGS_BLOCKED, &ec->flags)) {
 291                status = -EINVAL;
 292                goto unlock;
 293        }
 294        if (ec->global_lock) {
 295                status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk);
 296                if (ACPI_FAILURE(status)) {
 297                        status = -ENODEV;
 298                        goto unlock;
 299                }
 300        }
 301        if (ec_wait_ibf0(ec)) {
 302                pr_err(PREFIX "input buffer is not empty, "
 303                                "aborting transaction\n");
 304                status = -ETIME;
 305                goto end;
 306        }
 307        pr_debug(PREFIX "transaction start\n");
 308        /* disable GPE during transaction if storm is detected */
 309        if (test_bit(EC_FLAGS_GPE_STORM, &ec->flags)) {
 310                /* It has to be disabled, so that it doesn't trigger. */
 311                acpi_disable_gpe(NULL, ec->gpe);
 312        }
 313
 314        status = acpi_ec_transaction_unlocked(ec, t);
 315
 316        /* check if we received SCI during transaction */
 317        ec_check_sci_sync(ec, acpi_ec_read_status(ec));
 318        if (test_bit(EC_FLAGS_GPE_STORM, &ec->flags)) {
 319                msleep(1);
 320                /* It is safe to enable the GPE outside of the transaction. */
 321                acpi_enable_gpe(NULL, ec->gpe);
 322        } else if (t->irq_count > ACPI_EC_STORM_THRESHOLD) {
 323                pr_info(PREFIX "GPE storm detected, "
 324                        "transactions will use polling mode\n");
 325                set_bit(EC_FLAGS_GPE_STORM, &ec->flags);
 326        }
 327        pr_debug(PREFIX "transaction end\n");
 328end:
 329        if (ec->global_lock)
 330                acpi_release_global_lock(glk);
 331unlock:
 332        mutex_unlock(&ec->lock);
 333        return status;
 334}
 335
 336static int acpi_ec_burst_enable(struct acpi_ec *ec)
 337{
 338        u8 d;
 339        struct transaction t = {.command = ACPI_EC_BURST_ENABLE,
 340                                .wdata = NULL, .rdata = &d,
 341                                .wlen = 0, .rlen = 1};
 342
 343        return acpi_ec_transaction(ec, &t);
 344}
 345
 346static int acpi_ec_burst_disable(struct acpi_ec *ec)
 347{
 348        struct transaction t = {.command = ACPI_EC_BURST_DISABLE,
 349                                .wdata = NULL, .rdata = NULL,
 350                                .wlen = 0, .rlen = 0};
 351
 352        return (acpi_ec_read_status(ec) & ACPI_EC_FLAG_BURST) ?
 353                                acpi_ec_transaction(ec, &t) : 0;
 354}
 355
 356static int acpi_ec_read(struct acpi_ec *ec, u8 address, u8 * data)
 357{
 358        int result;
 359        u8 d;
 360        struct transaction t = {.command = ACPI_EC_COMMAND_READ,
 361                                .wdata = &address, .rdata = &d,
 362                                .wlen = 1, .rlen = 1};
 363
 364        result = acpi_ec_transaction(ec, &t);
 365        *data = d;
 366        return result;
 367}
 368
 369static int acpi_ec_write(struct acpi_ec *ec, u8 address, u8 data)
 370{
 371        u8 wdata[2] = { address, data };
 372        struct transaction t = {.command = ACPI_EC_COMMAND_WRITE,
 373                                .wdata = wdata, .rdata = NULL,
 374                                .wlen = 2, .rlen = 0};
 375
 376        return acpi_ec_transaction(ec, &t);
 377}
 378
 379/*
 380 * Externally callable EC access functions. For now, assume 1 EC only
 381 */
 382int ec_burst_enable(void)
 383{
 384        if (!first_ec)
 385                return -ENODEV;
 386        return acpi_ec_burst_enable(first_ec);
 387}
 388
 389EXPORT_SYMBOL(ec_burst_enable);
 390
 391int ec_burst_disable(void)
 392{
 393        if (!first_ec)
 394                return -ENODEV;
 395        return acpi_ec_burst_disable(first_ec);
 396}
 397
 398EXPORT_SYMBOL(ec_burst_disable);
 399
 400int ec_read(u8 addr, u8 * val)
 401{
 402        int err;
 403        u8 temp_data;
 404
 405        if (!first_ec)
 406                return -ENODEV;
 407
 408        err = acpi_ec_read(first_ec, addr, &temp_data);
 409
 410        if (!err) {
 411                *val = temp_data;
 412                return 0;
 413        } else
 414                return err;
 415}
 416
 417EXPORT_SYMBOL(ec_read);
 418
 419int ec_write(u8 addr, u8 val)
 420{
 421        int err;
 422
 423        if (!first_ec)
 424                return -ENODEV;
 425
 426        err = acpi_ec_write(first_ec, addr, val);
 427
 428        return err;
 429}
 430
 431EXPORT_SYMBOL(ec_write);
 432
 433int ec_transaction(u8 command,
 434                   const u8 * wdata, unsigned wdata_len,
 435                   u8 * rdata, unsigned rdata_len)
 436{
 437        struct transaction t = {.command = command,
 438                                .wdata = wdata, .rdata = rdata,
 439                                .wlen = wdata_len, .rlen = rdata_len};
 440        if (!first_ec)
 441                return -ENODEV;
 442
 443        return acpi_ec_transaction(first_ec, &t);
 444}
 445
 446EXPORT_SYMBOL(ec_transaction);
 447
 448/* Get the handle to the EC device */
 449acpi_handle ec_get_handle(void)
 450{
 451        if (!first_ec)
 452                return NULL;
 453        return first_ec->handle;
 454}
 455
 456EXPORT_SYMBOL(ec_get_handle);
 457
 458void acpi_ec_block_transactions(void)
 459{
 460        struct acpi_ec *ec = first_ec;
 461
 462        if (!ec)
 463                return;
 464
 465        mutex_lock(&ec->lock);
 466        /* Prevent transactions from being carried out */
 467        set_bit(EC_FLAGS_BLOCKED, &ec->flags);
 468        mutex_unlock(&ec->lock);
 469}
 470
 471void acpi_ec_unblock_transactions(void)
 472{
 473        struct acpi_ec *ec = first_ec;
 474
 475        if (!ec)
 476                return;
 477
 478        mutex_lock(&ec->lock);
 479        /* Allow transactions to be carried out again */
 480        clear_bit(EC_FLAGS_BLOCKED, &ec->flags);
 481        mutex_unlock(&ec->lock);
 482}
 483
 484void acpi_ec_unblock_transactions_early(void)
 485{
 486        /*
 487         * Allow transactions to happen again (this function is called from
 488         * atomic context during wakeup, so we don't need to acquire the mutex).
 489         */
 490        if (first_ec)
 491                clear_bit(EC_FLAGS_BLOCKED, &first_ec->flags);
 492}
 493
 494static int acpi_ec_query_unlocked(struct acpi_ec *ec, u8 * data)
 495{
 496        int result;
 497        u8 d;
 498        struct transaction t = {.command = ACPI_EC_COMMAND_QUERY,
 499                                .wdata = NULL, .rdata = &d,
 500                                .wlen = 0, .rlen = 1};
 501        if (!ec || !data)
 502                return -EINVAL;
 503        /*
 504         * Query the EC to find out which _Qxx method we need to evaluate.
 505         * Note that successful completion of the query causes the ACPI_EC_SCI
 506         * bit to be cleared (and thus clearing the interrupt source).
 507         */
 508        result = acpi_ec_transaction_unlocked(ec, &t);
 509        if (result)
 510                return result;
 511        if (!d)
 512                return -ENODATA;
 513        *data = d;
 514        return 0;
 515}
 516
 517/* --------------------------------------------------------------------------
 518                                Event Management
 519   -------------------------------------------------------------------------- */
 520int acpi_ec_add_query_handler(struct acpi_ec *ec, u8 query_bit,
 521                              acpi_handle handle, acpi_ec_query_func func,
 522                              void *data)
 523{
 524        struct acpi_ec_query_handler *handler =
 525            kzalloc(sizeof(struct acpi_ec_query_handler), GFP_KERNEL);
 526        if (!handler)
 527                return -ENOMEM;
 528
 529        handler->query_bit = query_bit;
 530        handler->handle = handle;
 531        handler->func = func;
 532        handler->data = data;
 533        mutex_lock(&ec->lock);
 534        list_add(&handler->node, &ec->list);
 535        mutex_unlock(&ec->lock);
 536        return 0;
 537}
 538
 539EXPORT_SYMBOL_GPL(acpi_ec_add_query_handler);
 540
 541void acpi_ec_remove_query_handler(struct acpi_ec *ec, u8 query_bit)
 542{
 543        struct acpi_ec_query_handler *handler, *tmp;
 544        mutex_lock(&ec->lock);
 545        list_for_each_entry_safe(handler, tmp, &ec->list, node) {
 546                if (query_bit == handler->query_bit) {
 547                        list_del(&handler->node);
 548                        kfree(handler);
 549                }
 550        }
 551        mutex_unlock(&ec->lock);
 552}
 553
 554EXPORT_SYMBOL_GPL(acpi_ec_remove_query_handler);
 555
 556static void acpi_ec_run(void *cxt)
 557{
 558        struct acpi_ec_query_handler *handler = cxt;
 559        if (!handler)
 560                return;
 561        pr_debug(PREFIX "start query execution\n");
 562        if (handler->func)
 563                handler->func(handler->data);
 564        else if (handler->handle)
 565                acpi_evaluate_object(handler->handle, NULL, NULL, NULL);
 566        pr_debug(PREFIX "stop query execution\n");
 567        kfree(handler);
 568}
 569
 570static int acpi_ec_sync_query(struct acpi_ec *ec)
 571{
 572        u8 value = 0;
 573        int status;
 574        struct acpi_ec_query_handler *handler, *copy;
 575        if ((status = acpi_ec_query_unlocked(ec, &value)))
 576                return status;
 577        list_for_each_entry(handler, &ec->list, node) {
 578                if (value == handler->query_bit) {
 579                        /* have custom handler for this bit */
 580                        copy = kmalloc(sizeof(*handler), GFP_KERNEL);
 581                        if (!copy)
 582                                return -ENOMEM;
 583                        memcpy(copy, handler, sizeof(*copy));
 584                        pr_debug(PREFIX "push query execution (0x%2x) on queue\n", value);
 585                        return acpi_os_execute((copy->func) ?
 586                                OSL_NOTIFY_HANDLER : OSL_GPE_HANDLER,
 587                                acpi_ec_run, copy);
 588                }
 589        }
 590        return 0;
 591}
 592
 593static void acpi_ec_gpe_query(void *ec_cxt)
 594{
 595        struct acpi_ec *ec = ec_cxt;
 596        if (!ec)
 597                return;
 598        mutex_lock(&ec->lock);
 599        acpi_ec_sync_query(ec);
 600        mutex_unlock(&ec->lock);
 601}
 602
 603static int ec_check_sci(struct acpi_ec *ec, u8 state)
 604{
 605        if (state & ACPI_EC_FLAG_SCI) {
 606                if (!test_and_set_bit(EC_FLAGS_QUERY_PENDING, &ec->flags)) {
 607                        pr_debug(PREFIX "push gpe query to the queue\n");
 608                        return acpi_os_execute(OSL_NOTIFY_HANDLER,
 609                                acpi_ec_gpe_query, ec);
 610                }
 611        }
 612        return 0;
 613}
 614
 615static u32 acpi_ec_gpe_handler(acpi_handle gpe_device,
 616        u32 gpe_number, void *data)
 617{
 618        struct acpi_ec *ec = data;
 619
 620        pr_debug(PREFIX "~~~> interrupt\n");
 621
 622        advance_transaction(ec, acpi_ec_read_status(ec));
 623        if (ec_transaction_done(ec) &&
 624            (acpi_ec_read_status(ec) & ACPI_EC_FLAG_IBF) == 0) {
 625                wake_up(&ec->wait);
 626                ec_check_sci(ec, acpi_ec_read_status(ec));
 627        }
 628        return ACPI_INTERRUPT_HANDLED | ACPI_REENABLE_GPE;
 629}
 630
 631/* --------------------------------------------------------------------------
 632                             Address Space Management
 633   -------------------------------------------------------------------------- */
 634
 635static acpi_status
 636acpi_ec_space_handler(u32 function, acpi_physical_address address,
 637                      u32 bits, u64 *value64,
 638                      void *handler_context, void *region_context)
 639{
 640        struct acpi_ec *ec = handler_context;
 641        int result = 0, i, bytes = bits / 8;
 642        u8 *value = (u8 *)value64;
 643
 644        if ((address > 0xFF) || !value || !handler_context)
 645                return AE_BAD_PARAMETER;
 646
 647        if (function != ACPI_READ && function != ACPI_WRITE)
 648                return AE_BAD_PARAMETER;
 649
 650        if (EC_FLAGS_MSI || bits > 8)
 651                acpi_ec_burst_enable(ec);
 652
 653        for (i = 0; i < bytes; ++i, ++address, ++value)
 654                result = (function == ACPI_READ) ?
 655                        acpi_ec_read(ec, address, value) :
 656                        acpi_ec_write(ec, address, *value);
 657
 658        if (EC_FLAGS_MSI || bits > 8)
 659                acpi_ec_burst_disable(ec);
 660
 661        switch (result) {
 662        case -EINVAL:
 663                return AE_BAD_PARAMETER;
 664                break;
 665        case -ENODEV:
 666                return AE_NOT_FOUND;
 667                break;
 668        case -ETIME:
 669                return AE_TIME;
 670                break;
 671        default:
 672                return AE_OK;
 673        }
 674}
 675
 676/* --------------------------------------------------------------------------
 677                               Driver Interface
 678   -------------------------------------------------------------------------- */
 679static acpi_status
 680ec_parse_io_ports(struct acpi_resource *resource, void *context);
 681
 682static struct acpi_ec *make_acpi_ec(void)
 683{
 684        struct acpi_ec *ec = kzalloc(sizeof(struct acpi_ec), GFP_KERNEL);
 685        if (!ec)
 686                return NULL;
 687        ec->flags = 1 << EC_FLAGS_QUERY_PENDING;
 688        mutex_init(&ec->lock);
 689        init_waitqueue_head(&ec->wait);
 690        INIT_LIST_HEAD(&ec->list);
 691        spin_lock_init(&ec->curr_lock);
 692        return ec;
 693}
 694
 695static acpi_status
 696acpi_ec_register_query_methods(acpi_handle handle, u32 level,
 697                               void *context, void **return_value)
 698{
 699        char node_name[5];
 700        struct acpi_buffer buffer = { sizeof(node_name), node_name };
 701        struct acpi_ec *ec = context;
 702        int value = 0;
 703        acpi_status status;
 704
 705        status = acpi_get_name(handle, ACPI_SINGLE_NAME, &buffer);
 706
 707        if (ACPI_SUCCESS(status) && sscanf(node_name, "_Q%x", &value) == 1) {
 708                acpi_ec_add_query_handler(ec, value, handle, NULL, NULL);
 709        }
 710        return AE_OK;
 711}
 712
 713static acpi_status
 714ec_parse_device(acpi_handle handle, u32 Level, void *context, void **retval)
 715{
 716        acpi_status status;
 717        unsigned long long tmp = 0;
 718
 719        struct acpi_ec *ec = context;
 720
 721        /* clear addr values, ec_parse_io_ports depend on it */
 722        ec->command_addr = ec->data_addr = 0;
 723
 724        status = acpi_walk_resources(handle, METHOD_NAME__CRS,
 725                                     ec_parse_io_ports, ec);
 726        if (ACPI_FAILURE(status))
 727                return status;
 728
 729        /* Get GPE bit assignment (EC events). */
 730        /* TODO: Add support for _GPE returning a package */
 731        status = acpi_evaluate_integer(handle, "_GPE", NULL, &tmp);
 732        if (ACPI_FAILURE(status))
 733                return status;
 734        ec->gpe = tmp;
 735        /* Use the global lock for all EC transactions? */
 736        tmp = 0;
 737        acpi_evaluate_integer(handle, "_GLK", NULL, &tmp);
 738        ec->global_lock = tmp;
 739        ec->handle = handle;
 740        return AE_CTRL_TERMINATE;
 741}
 742
 743static int ec_install_handlers(struct acpi_ec *ec)
 744{
 745        acpi_status status;
 746        if (test_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags))
 747                return 0;
 748        status = acpi_install_gpe_handler(NULL, ec->gpe,
 749                                  ACPI_GPE_EDGE_TRIGGERED,
 750                                  &acpi_ec_gpe_handler, ec);
 751        if (ACPI_FAILURE(status))
 752                return -ENODEV;
 753
 754        acpi_enable_gpe(NULL, ec->gpe);
 755        status = acpi_install_address_space_handler(ec->handle,
 756                                                    ACPI_ADR_SPACE_EC,
 757                                                    &acpi_ec_space_handler,
 758                                                    NULL, ec);
 759        if (ACPI_FAILURE(status)) {
 760                if (status == AE_NOT_FOUND) {
 761                        /*
 762                         * Maybe OS fails in evaluating the _REG object.
 763                         * The AE_NOT_FOUND error will be ignored and OS
 764                         * continue to initialize EC.
 765                         */
 766                        printk(KERN_ERR "Fail in evaluating the _REG object"
 767                                " of EC device. Broken bios is suspected.\n");
 768                } else {
 769                        acpi_remove_gpe_handler(NULL, ec->gpe,
 770                                &acpi_ec_gpe_handler);
 771                        acpi_disable_gpe(NULL, ec->gpe);
 772                        return -ENODEV;
 773                }
 774        }
 775
 776        set_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags);
 777        return 0;
 778}
 779
 780static void ec_remove_handlers(struct acpi_ec *ec)
 781{
 782        acpi_disable_gpe(NULL, ec->gpe);
 783        if (ACPI_FAILURE(acpi_remove_address_space_handler(ec->handle,
 784                                ACPI_ADR_SPACE_EC, &acpi_ec_space_handler)))
 785                pr_err(PREFIX "failed to remove space handler\n");
 786        if (ACPI_FAILURE(acpi_remove_gpe_handler(NULL, ec->gpe,
 787                                &acpi_ec_gpe_handler)))
 788                pr_err(PREFIX "failed to remove gpe handler\n");
 789        clear_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags);
 790}
 791
 792static int acpi_ec_add(struct acpi_device *device)
 793{
 794        struct acpi_ec *ec = NULL;
 795        int ret;
 796
 797        strcpy(acpi_device_name(device), ACPI_EC_DEVICE_NAME);
 798        strcpy(acpi_device_class(device), ACPI_EC_CLASS);
 799
 800        /* Check for boot EC */
 801        if (boot_ec &&
 802            (boot_ec->handle == device->handle ||
 803             boot_ec->handle == ACPI_ROOT_OBJECT)) {
 804                ec = boot_ec;
 805                boot_ec = NULL;
 806        } else {
 807                ec = make_acpi_ec();
 808                if (!ec)
 809                        return -ENOMEM;
 810        }
 811        if (ec_parse_device(device->handle, 0, ec, NULL) !=
 812                AE_CTRL_TERMINATE) {
 813                        kfree(ec);
 814                        return -EINVAL;
 815        }
 816
 817        /* Find and register all query methods */
 818        acpi_walk_namespace(ACPI_TYPE_METHOD, ec->handle, 1,
 819                            acpi_ec_register_query_methods, NULL, ec, NULL);
 820
 821        if (!first_ec)
 822                first_ec = ec;
 823        device->driver_data = ec;
 824
 825        ret = !!request_region(ec->data_addr, 1, "EC data");
 826        WARN(!ret, "Could not request EC data io port 0x%lx", ec->data_addr);
 827        ret = !!request_region(ec->command_addr, 1, "EC cmd");
 828        WARN(!ret, "Could not request EC cmd io port 0x%lx", ec->command_addr);
 829
 830        pr_info(PREFIX "GPE = 0x%lx, I/O: command/status = 0x%lx, data = 0x%lx\n",
 831                          ec->gpe, ec->command_addr, ec->data_addr);
 832
 833        ret = ec_install_handlers(ec);
 834
 835        /* EC is fully operational, allow queries */
 836        clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags);
 837        return ret;
 838}
 839
 840static int acpi_ec_remove(struct acpi_device *device, int type)
 841{
 842        struct acpi_ec *ec;
 843        struct acpi_ec_query_handler *handler, *tmp;
 844
 845        if (!device)
 846                return -EINVAL;
 847
 848        ec = acpi_driver_data(device);
 849        ec_remove_handlers(ec);
 850        mutex_lock(&ec->lock);
 851        list_for_each_entry_safe(handler, tmp, &ec->list, node) {
 852                list_del(&handler->node);
 853                kfree(handler);
 854        }
 855        mutex_unlock(&ec->lock);
 856        release_region(ec->data_addr, 1);
 857        release_region(ec->command_addr, 1);
 858        device->driver_data = NULL;
 859        if (ec == first_ec)
 860                first_ec = NULL;
 861        kfree(ec);
 862        return 0;
 863}
 864
 865static acpi_status
 866ec_parse_io_ports(struct acpi_resource *resource, void *context)
 867{
 868        struct acpi_ec *ec = context;
 869
 870        if (resource->type != ACPI_RESOURCE_TYPE_IO)
 871                return AE_OK;
 872
 873        /*
 874         * The first address region returned is the data port, and
 875         * the second address region returned is the status/command
 876         * port.
 877         */
 878        if (ec->data_addr == 0)
 879                ec->data_addr = resource->data.io.minimum;
 880        else if (ec->command_addr == 0)
 881                ec->command_addr = resource->data.io.minimum;
 882        else
 883                return AE_CTRL_TERMINATE;
 884
 885        return AE_OK;
 886}
 887
 888int __init acpi_boot_ec_enable(void)
 889{
 890        if (!boot_ec || test_bit(EC_FLAGS_HANDLERS_INSTALLED, &boot_ec->flags))
 891                return 0;
 892        if (!ec_install_handlers(boot_ec)) {
 893                first_ec = boot_ec;
 894                return 0;
 895        }
 896        return -EFAULT;
 897}
 898
 899static const struct acpi_device_id ec_device_ids[] = {
 900        {"PNP0C09", 0},
 901        {"", 0},
 902};
 903
 904/* Some BIOS do not survive early DSDT scan, skip it */
 905static int ec_skip_dsdt_scan(const struct dmi_system_id *id)
 906{
 907        EC_FLAGS_SKIP_DSDT_SCAN = 1;
 908        return 0;
 909}
 910
 911/* ASUStek often supplies us with broken ECDT, validate it */
 912static int ec_validate_ecdt(const struct dmi_system_id *id)
 913{
 914        EC_FLAGS_VALIDATE_ECDT = 1;
 915        return 0;
 916}
 917
 918/* MSI EC needs special treatment, enable it */
 919static int ec_flag_msi(const struct dmi_system_id *id)
 920{
 921        printk(KERN_DEBUG PREFIX "Detected MSI hardware, enabling workarounds.\n");
 922        EC_FLAGS_MSI = 1;
 923        EC_FLAGS_VALIDATE_ECDT = 1;
 924        return 0;
 925}
 926
 927static struct dmi_system_id __initdata ec_dmi_table[] = {
 928        {
 929        ec_skip_dsdt_scan, "Compal JFL92", {
 930        DMI_MATCH(DMI_BIOS_VENDOR, "COMPAL"),
 931        DMI_MATCH(DMI_BOARD_NAME, "JFL92") }, NULL},
 932        {
 933        ec_flag_msi, "MSI hardware", {
 934        DMI_MATCH(DMI_BIOS_VENDOR, "Micro-Star")}, NULL},
 935        {
 936        ec_flag_msi, "MSI hardware", {
 937        DMI_MATCH(DMI_SYS_VENDOR, "Micro-Star")}, NULL},
 938        {
 939        ec_flag_msi, "MSI hardware", {
 940        DMI_MATCH(DMI_CHASSIS_VENDOR, "MICRO-Star")}, NULL},
 941        {
 942        ec_flag_msi, "MSI hardware", {
 943        DMI_MATCH(DMI_CHASSIS_VENDOR, "MICRO-STAR")}, NULL},
 944        {
 945        ec_flag_msi, "Quanta hardware", {
 946        DMI_MATCH(DMI_SYS_VENDOR, "Quanta"),
 947        DMI_MATCH(DMI_PRODUCT_NAME, "TW8/SW8/DW8"),}, NULL},
 948        {
 949        ec_flag_msi, "Quanta hardware", {
 950        DMI_MATCH(DMI_SYS_VENDOR, "Quanta"),
 951        DMI_MATCH(DMI_PRODUCT_NAME, "TW9/SW9"),}, NULL},
 952        {
 953        ec_validate_ecdt, "ASUS hardware", {
 954        DMI_MATCH(DMI_BIOS_VENDOR, "ASUS") }, NULL},
 955        {
 956        ec_validate_ecdt, "ASUS hardware", {
 957        DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTeK Computer Inc.") }, NULL},
 958        {},
 959};
 960
 961
 962int __init acpi_ec_ecdt_probe(void)
 963{
 964        acpi_status status;
 965        struct acpi_ec *saved_ec = NULL;
 966        struct acpi_table_ecdt *ecdt_ptr;
 967
 968        boot_ec = make_acpi_ec();
 969        if (!boot_ec)
 970                return -ENOMEM;
 971        /*
 972         * Generate a boot ec context
 973         */
 974        dmi_check_system(ec_dmi_table);
 975        status = acpi_get_table(ACPI_SIG_ECDT, 1,
 976                                (struct acpi_table_header **)&ecdt_ptr);
 977        if (ACPI_SUCCESS(status)) {
 978                pr_info(PREFIX "EC description table is found, configuring boot EC\n");
 979                boot_ec->command_addr = ecdt_ptr->control.address;
 980                boot_ec->data_addr = ecdt_ptr->data.address;
 981                boot_ec->gpe = ecdt_ptr->gpe;
 982                boot_ec->handle = ACPI_ROOT_OBJECT;
 983                acpi_get_handle(ACPI_ROOT_OBJECT, ecdt_ptr->id, &boot_ec->handle);
 984                /* Don't trust ECDT, which comes from ASUSTek */
 985                if (!EC_FLAGS_VALIDATE_ECDT)
 986                        goto install;
 987                saved_ec = kmemdup(boot_ec, sizeof(struct acpi_ec), GFP_KERNEL);
 988                if (!saved_ec)
 989                        return -ENOMEM;
 990        /* fall through */
 991        }
 992
 993        if (EC_FLAGS_SKIP_DSDT_SCAN)
 994                return -ENODEV;
 995
 996        /* This workaround is needed only on some broken machines,
 997         * which require early EC, but fail to provide ECDT */
 998        printk(KERN_DEBUG PREFIX "Look up EC in DSDT\n");
 999        status = acpi_get_devices(ec_device_ids[0].id, ec_parse_device,
1000                                        boot_ec, NULL);
1001        /* Check that acpi_get_devices actually find something */
1002        if (ACPI_FAILURE(status) || !boot_ec->handle)
1003                goto error;
1004        if (saved_ec) {
1005                /* try to find good ECDT from ASUSTek */
1006                if (saved_ec->command_addr != boot_ec->command_addr ||
1007                    saved_ec->data_addr != boot_ec->data_addr ||
1008                    saved_ec->gpe != boot_ec->gpe ||
1009                    saved_ec->handle != boot_ec->handle)
1010                        pr_info(PREFIX "ASUSTek keeps feeding us with broken "
1011                        "ECDT tables, which are very hard to workaround. "
1012                        "Trying to use DSDT EC info instead. Please send "
1013                        "output of acpidump to linux-acpi@vger.kernel.org\n");
1014                kfree(saved_ec);
1015                saved_ec = NULL;
1016        } else {
1017                /* We really need to limit this workaround, the only ASUS,
1018                * which needs it, has fake EC._INI method, so use it as flag.
1019                * Keep boot_ec struct as it will be needed soon.
1020                */
1021                acpi_handle dummy;
1022                if (!dmi_name_in_vendors("ASUS") ||
1023                    ACPI_FAILURE(acpi_get_handle(boot_ec->handle, "_INI",
1024                                                        &dummy)))
1025                        return -ENODEV;
1026        }
1027install:
1028        if (!ec_install_handlers(boot_ec)) {
1029                first_ec = boot_ec;
1030                return 0;
1031        }
1032error:
1033        kfree(boot_ec);
1034        boot_ec = NULL;
1035        return -ENODEV;
1036}
1037
1038static struct acpi_driver acpi_ec_driver = {
1039        .name = "ec",
1040        .class = ACPI_EC_CLASS,
1041        .ids = ec_device_ids,
1042        .ops = {
1043                .add = acpi_ec_add,
1044                .remove = acpi_ec_remove,
1045                },
1046};
1047
1048int __init acpi_ec_init(void)
1049{
1050        int result = 0;
1051
1052        /* Now register the driver for the EC */
1053        result = acpi_bus_register_driver(&acpi_ec_driver);
1054        if (result < 0)
1055                return -ENODEV;
1056
1057        return result;
1058}
1059
1060/* EC driver currently not unloadable */
1061#if 0
1062static void __exit acpi_ec_exit(void)
1063{
1064
1065        acpi_bus_unregister_driver(&acpi_ec_driver);
1066        return;
1067}
1068#endif  /* 0 */
1069
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