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/proc_fs.h>
  38#include <linux/seq_file.h>
  39#include <linux/interrupt.h>
  40#include <linux/list.h>
  41#include <linux/spinlock.h>
  42#include <asm/io.h>
  43#include <acpi/acpi_bus.h>
  44#include <acpi/acpi_drivers.h>
  45
  46#define ACPI_EC_CLASS                   "embedded_controller"
  47#define ACPI_EC_DEVICE_NAME             "Embedded Controller"
  48#define ACPI_EC_FILE_INFO               "info"
  49
  50#undef PREFIX
  51#define PREFIX                          "ACPI: EC: "
  52
  53/* EC status register */
  54#define ACPI_EC_FLAG_OBF        0x01    /* Output buffer full */
  55#define ACPI_EC_FLAG_IBF        0x02    /* Input buffer full */
  56#define ACPI_EC_FLAG_BURST      0x10    /* burst mode */
  57#define ACPI_EC_FLAG_SCI        0x20    /* EC-SCI occurred */
  58
  59/* EC commands */
  60enum ec_command {
  61        ACPI_EC_COMMAND_READ = 0x80,
  62        ACPI_EC_COMMAND_WRITE = 0x81,
  63        ACPI_EC_BURST_ENABLE = 0x82,
  64        ACPI_EC_BURST_DISABLE = 0x83,
  65        ACPI_EC_COMMAND_QUERY = 0x84,
  66};
  67
  68#define ACPI_EC_DELAY           500     /* Wait 500ms max. during EC ops */
  69#define ACPI_EC_UDELAY_GLK      1000    /* Wait 1ms max. to get global lock */
  70#define ACPI_EC_CDELAY          10      /* Wait 10us before polling EC */
  71
  72#define ACPI_EC_STORM_THRESHOLD 8       /* number of false interrupts
  73                                           per one transaction */
  74
  75enum {
  76        EC_FLAGS_QUERY_PENDING,         /* Query is pending */
  77        EC_FLAGS_GPE_MODE,              /* Expect GPE to be sent
  78                                         * for status change */
  79        EC_FLAGS_NO_GPE,                /* Don't use GPE mode */
  80        EC_FLAGS_GPE_STORM,             /* GPE storm detected */
  81        EC_FLAGS_HANDLERS_INSTALLED     /* Handlers for GPE and
  82                                         * OpReg are installed */
  83};
  84
  85/* If we find an EC via the ECDT, we need to keep a ptr to its context */
  86/* External interfaces use first EC only, so remember */
  87typedef int (*acpi_ec_query_func) (void *data);
  88
  89struct acpi_ec_query_handler {
  90        struct list_head node;
  91        acpi_ec_query_func func;
  92        acpi_handle handle;
  93        void *data;
  94        u8 query_bit;
  95};
  96
  97struct transaction {
  98        const u8 *wdata;
  99        u8 *rdata;
 100        unsigned short irq_count;
 101        u8 command;
 102        u8 wi;
 103        u8 ri;
 104        u8 wlen;
 105        u8 rlen;
 106        bool done;
 107};
 108
 109static struct acpi_ec {
 110        acpi_handle handle;
 111        unsigned long gpe;
 112        unsigned long command_addr;
 113        unsigned long data_addr;
 114        unsigned long global_lock;
 115        unsigned long flags;
 116        struct mutex lock;
 117        wait_queue_head_t wait;
 118        struct list_head list;
 119        struct transaction *curr;
 120        spinlock_t curr_lock;
 121} *boot_ec, *first_ec;
 122
 123static int EC_FLAGS_MSI; /* Out-of-spec MSI controller */
 124
 125/* --------------------------------------------------------------------------
 126                             Transaction Management
 127   -------------------------------------------------------------------------- */
 128
 129static inline u8 acpi_ec_read_status(struct acpi_ec *ec)
 130{
 131        u8 x = inb(ec->command_addr);
 132        pr_debug(PREFIX "---> status = 0x%2.2x\n", x);
 133        return x;
 134}
 135
 136static inline u8 acpi_ec_read_data(struct acpi_ec *ec)
 137{
 138        u8 x = inb(ec->data_addr);
 139        pr_debug(PREFIX "---> data = 0x%2.2x\n", x);
 140        return x;
 141}
 142
 143static inline void acpi_ec_write_cmd(struct acpi_ec *ec, u8 command)
 144{
 145        pr_debug(PREFIX "<--- command = 0x%2.2x\n", command);
 146        outb(command, ec->command_addr);
 147}
 148
 149static inline void acpi_ec_write_data(struct acpi_ec *ec, u8 data)
 150{
 151        pr_debug(PREFIX "<--- data = 0x%2.2x\n", data);
 152        outb(data, ec->data_addr);
 153}
 154
 155static int ec_transaction_done(struct acpi_ec *ec)
 156{
 157        unsigned long flags;
 158        int ret = 0;
 159        spin_lock_irqsave(&ec->curr_lock, flags);
 160        if (!ec->curr || ec->curr->done)
 161                ret = 1;
 162        spin_unlock_irqrestore(&ec->curr_lock, flags);
 163        return ret;
 164}
 165
 166static void start_transaction(struct acpi_ec *ec)
 167{
 168        ec->curr->irq_count = ec->curr->wi = ec->curr->ri = 0;
 169        ec->curr->done = false;
 170        acpi_ec_write_cmd(ec, ec->curr->command);
 171}
 172
 173static void gpe_transaction(struct acpi_ec *ec, u8 status)
 174{
 175        unsigned long flags;
 176        spin_lock_irqsave(&ec->curr_lock, flags);
 177        if (!ec->curr)
 178                goto unlock;
 179        if (ec->curr->wlen > ec->curr->wi) {
 180                if ((status & ACPI_EC_FLAG_IBF) == 0)
 181                        acpi_ec_write_data(ec,
 182                                ec->curr->wdata[ec->curr->wi++]);
 183                else
 184                        goto err;
 185        } else if (ec->curr->rlen > ec->curr->ri) {
 186                if ((status & ACPI_EC_FLAG_OBF) == 1) {
 187                        ec->curr->rdata[ec->curr->ri++] = acpi_ec_read_data(ec);
 188                        if (ec->curr->rlen == ec->curr->ri)
 189                                ec->curr->done = true;
 190                } else
 191                        goto err;
 192        } else if (ec->curr->wlen == ec->curr->wi &&
 193                   (status & ACPI_EC_FLAG_IBF) == 0)
 194                ec->curr->done = true;
 195        goto unlock;
 196err:
 197        /* false interrupt, state didn't change */
 198        if (in_interrupt())
 199                ++ec->curr->irq_count;
 200unlock:
 201        spin_unlock_irqrestore(&ec->curr_lock, flags);
 202}
 203
 204static int acpi_ec_wait(struct acpi_ec *ec)
 205{
 206        if (wait_event_timeout(ec->wait, ec_transaction_done(ec),
 207                               msecs_to_jiffies(ACPI_EC_DELAY)))
 208                return 0;
 209        /* try restart command if we get any false interrupts */
 210        if (ec->curr->irq_count &&
 211            (acpi_ec_read_status(ec) & ACPI_EC_FLAG_IBF) == 0) {
 212                pr_debug(PREFIX "controller reset, restart transaction\n");
 213                start_transaction(ec);
 214                if (wait_event_timeout(ec->wait, ec_transaction_done(ec),
 215                                        msecs_to_jiffies(ACPI_EC_DELAY)))
 216                        return 0;
 217        }
 218        /* missing GPEs, switch back to poll mode */
 219        if (printk_ratelimit())
 220                pr_info(PREFIX "missing confirmations, "
 221                                "switch off interrupt mode.\n");
 222        set_bit(EC_FLAGS_NO_GPE, &ec->flags);
 223        clear_bit(EC_FLAGS_GPE_MODE, &ec->flags);
 224        return 1;
 225}
 226
 227static void acpi_ec_gpe_query(void *ec_cxt);
 228
 229static int ec_check_sci(struct acpi_ec *ec, u8 state)
 230{
 231        if (state & ACPI_EC_FLAG_SCI) {
 232                if (!test_and_set_bit(EC_FLAGS_QUERY_PENDING, &ec->flags))
 233                        return acpi_os_execute(OSL_EC_BURST_HANDLER,
 234                                acpi_ec_gpe_query, ec);
 235        }
 236        return 0;
 237}
 238
 239static void ec_delay(void)
 240{
 241        /* EC in MSI notebooks don't tolerate delays other than 550 usec */
 242        if (EC_FLAGS_MSI)
 243                udelay(ACPI_EC_DELAY);
 244        else
 245                /* Use shortest sleep available */
 246                msleep(1);
 247}
 248
 249static int ec_poll(struct acpi_ec *ec)
 250{
 251        unsigned long delay = jiffies + msecs_to_jiffies(ACPI_EC_DELAY);
 252        udelay(ACPI_EC_CDELAY);
 253        while (time_before(jiffies, delay)) {
 254                gpe_transaction(ec, acpi_ec_read_status(ec));
 255                ec_delay();
 256                if (ec_transaction_done(ec))
 257                        return 0;
 258        }
 259        return -ETIME;
 260}
 261
 262static int acpi_ec_transaction_unlocked(struct acpi_ec *ec,
 263                                        struct transaction *t,
 264                                        int force_poll)
 265{
 266        unsigned long tmp;
 267        int ret = 0;
 268        pr_debug(PREFIX "transaction start\n");
 269        /* disable GPE during transaction if storm is detected */
 270        if (test_bit(EC_FLAGS_GPE_STORM, &ec->flags)) {
 271                clear_bit(EC_FLAGS_GPE_MODE, &ec->flags);
 272                acpi_disable_gpe(NULL, ec->gpe);
 273        }
 274        if (EC_FLAGS_MSI)
 275                udelay(ACPI_EC_DELAY);
 276        /* start transaction */
 277        spin_lock_irqsave(&ec->curr_lock, tmp);
 278        /* following two actions should be kept atomic */
 279        ec->curr = t;
 280        start_transaction(ec);
 281        if (ec->curr->command == ACPI_EC_COMMAND_QUERY)
 282                clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags);
 283        spin_unlock_irqrestore(&ec->curr_lock, tmp);
 284        /* if we selected poll mode or failed in GPE-mode do a poll loop */
 285        if (force_poll ||
 286            !test_bit(EC_FLAGS_GPE_MODE, &ec->flags) ||
 287            acpi_ec_wait(ec))
 288                ret = ec_poll(ec);
 289        pr_debug(PREFIX "transaction end\n");
 290        spin_lock_irqsave(&ec->curr_lock, tmp);
 291        ec->curr = NULL;
 292        spin_unlock_irqrestore(&ec->curr_lock, tmp);
 293        if (test_bit(EC_FLAGS_GPE_STORM, &ec->flags)) {
 294                /* check if we received SCI during transaction */
 295                ec_check_sci(ec, acpi_ec_read_status(ec));
 296                /* it is safe to enable GPE outside of transaction */
 297                acpi_enable_gpe(NULL, ec->gpe);
 298        } else if (test_bit(EC_FLAGS_GPE_MODE, &ec->flags) &&
 299                   t->irq_count > ACPI_EC_STORM_THRESHOLD) {
 300                pr_info(PREFIX "GPE storm detected, "
 301                        "transactions will use polling mode\n");
 302                set_bit(EC_FLAGS_GPE_STORM, &ec->flags);
 303        }
 304        return ret;
 305}
 306
 307static int ec_check_ibf0(struct acpi_ec *ec)
 308{
 309        u8 status = acpi_ec_read_status(ec);
 310        return (status & ACPI_EC_FLAG_IBF) == 0;
 311}
 312
 313static int ec_wait_ibf0(struct acpi_ec *ec)
 314{
 315        unsigned long delay = jiffies + msecs_to_jiffies(ACPI_EC_DELAY);
 316        /* interrupt wait manually if GPE mode is not active */
 317        unsigned long timeout = test_bit(EC_FLAGS_GPE_MODE, &ec->flags) ?
 318                msecs_to_jiffies(ACPI_EC_DELAY) : msecs_to_jiffies(1);
 319        while (time_before(jiffies, delay))
 320                if (wait_event_timeout(ec->wait, ec_check_ibf0(ec), timeout))
 321                        return 0;
 322        return -ETIME;
 323}
 324
 325static int acpi_ec_transaction(struct acpi_ec *ec, struct transaction *t,
 326                               int force_poll)
 327{
 328        int status;
 329        u32 glk;
 330        if (!ec || (!t) || (t->wlen && !t->wdata) || (t->rlen && !t->rdata))
 331                return -EINVAL;
 332        if (t->rdata)
 333                memset(t->rdata, 0, t->rlen);
 334        mutex_lock(&ec->lock);
 335        if (ec->global_lock) {
 336                status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk);
 337                if (ACPI_FAILURE(status)) {
 338                        status = -ENODEV;
 339                        goto unlock;
 340                }
 341        }
 342        if (ec_wait_ibf0(ec)) {
 343                pr_err(PREFIX "input buffer is not empty, "
 344                                "aborting transaction\n");
 345                status = -ETIME;
 346                goto end;
 347        }
 348        status = acpi_ec_transaction_unlocked(ec, t, force_poll);
 349end:
 350        if (ec->global_lock)
 351                acpi_release_global_lock(glk);
 352unlock:
 353        mutex_unlock(&ec->lock);
 354        return status;
 355}
 356
 357/*
 358 * Note: samsung nv5000 doesn't work with ec burst mode.
 359 * http://bugzilla.kernel.org/show_bug.cgi?id=4980
 360 */
 361static int acpi_ec_burst_enable(struct acpi_ec *ec)
 362{
 363        u8 d;
 364        struct transaction t = {.command = ACPI_EC_BURST_ENABLE,
 365                                .wdata = NULL, .rdata = &d,
 366                                .wlen = 0, .rlen = 1};
 367
 368        return acpi_ec_transaction(ec, &t, 0);
 369}
 370
 371static int acpi_ec_burst_disable(struct acpi_ec *ec)
 372{
 373        struct transaction t = {.command = ACPI_EC_BURST_DISABLE,
 374                                .wdata = NULL, .rdata = NULL,
 375                                .wlen = 0, .rlen = 0};
 376
 377        return (acpi_ec_read_status(ec) & ACPI_EC_FLAG_BURST) ?
 378                                acpi_ec_transaction(ec, &t, 0) : 0;
 379}
 380
 381static int acpi_ec_read(struct acpi_ec *ec, u8 address, u8 * data)
 382{
 383        int result;
 384        u8 d;
 385        struct transaction t = {.command = ACPI_EC_COMMAND_READ,
 386                                .wdata = &address, .rdata = &d,
 387                                .wlen = 1, .rlen = 1};
 388
 389        result = acpi_ec_transaction(ec, &t, 0);
 390        *data = d;
 391        return result;
 392}
 393
 394static int acpi_ec_write(struct acpi_ec *ec, u8 address, u8 data)
 395{
 396        u8 wdata[2] = { address, data };
 397        struct transaction t = {.command = ACPI_EC_COMMAND_WRITE,
 398                                .wdata = wdata, .rdata = NULL,
 399                                .wlen = 2, .rlen = 0};
 400
 401        return acpi_ec_transaction(ec, &t, 0);
 402}
 403
 404/*
 405 * Externally callable EC access functions. For now, assume 1 EC only
 406 */
 407int ec_burst_enable(void)
 408{
 409        if (!first_ec)
 410                return -ENODEV;
 411        return acpi_ec_burst_enable(first_ec);
 412}
 413
 414EXPORT_SYMBOL(ec_burst_enable);
 415
 416int ec_burst_disable(void)
 417{
 418        if (!first_ec)
 419                return -ENODEV;
 420        return acpi_ec_burst_disable(first_ec);
 421}
 422
 423EXPORT_SYMBOL(ec_burst_disable);
 424
 425int ec_read(u8 addr, u8 * val)
 426{
 427        int err;
 428        u8 temp_data;
 429
 430        if (!first_ec)
 431                return -ENODEV;
 432
 433        err = acpi_ec_read(first_ec, addr, &temp_data);
 434
 435        if (!err) {
 436                *val = temp_data;
 437                return 0;
 438        } else
 439                return err;
 440}
 441
 442EXPORT_SYMBOL(ec_read);
 443
 444int ec_write(u8 addr, u8 val)
 445{
 446        int err;
 447
 448        if (!first_ec)
 449                return -ENODEV;
 450
 451        err = acpi_ec_write(first_ec, addr, val);
 452
 453        return err;
 454}
 455
 456EXPORT_SYMBOL(ec_write);
 457
 458int ec_transaction(u8 command,
 459                   const u8 * wdata, unsigned wdata_len,
 460                   u8 * rdata, unsigned rdata_len,
 461                   int force_poll)
 462{
 463        struct transaction t = {.command = command,
 464                                .wdata = wdata, .rdata = rdata,
 465                                .wlen = wdata_len, .rlen = rdata_len};
 466        if (!first_ec)
 467                return -ENODEV;
 468
 469        return acpi_ec_transaction(first_ec, &t, force_poll);
 470}
 471
 472EXPORT_SYMBOL(ec_transaction);
 473
 474static int acpi_ec_query(struct acpi_ec *ec, u8 * data)
 475{
 476        int result;
 477        u8 d;
 478        struct transaction t = {.command = ACPI_EC_COMMAND_QUERY,
 479                                .wdata = NULL, .rdata = &d,
 480                                .wlen = 0, .rlen = 1};
 481        if (!ec || !data)
 482                return -EINVAL;
 483
 484        /*
 485         * Query the EC to find out which _Qxx method we need to evaluate.
 486         * Note that successful completion of the query causes the ACPI_EC_SCI
 487         * bit to be cleared (and thus clearing the interrupt source).
 488         */
 489
 490        result = acpi_ec_transaction(ec, &t, 0);
 491        if (result)
 492                return result;
 493
 494        if (!d)
 495                return -ENODATA;
 496
 497        *data = d;
 498        return 0;
 499}
 500
 501/* --------------------------------------------------------------------------
 502                                Event Management
 503   -------------------------------------------------------------------------- */
 504int acpi_ec_add_query_handler(struct acpi_ec *ec, u8 query_bit,
 505                              acpi_handle handle, acpi_ec_query_func func,
 506                              void *data)
 507{
 508        struct acpi_ec_query_handler *handler =
 509            kzalloc(sizeof(struct acpi_ec_query_handler), GFP_KERNEL);
 510        if (!handler)
 511                return -ENOMEM;
 512
 513        handler->query_bit = query_bit;
 514        handler->handle = handle;
 515        handler->func = func;
 516        handler->data = data;
 517        mutex_lock(&ec->lock);
 518        list_add(&handler->node, &ec->list);
 519        mutex_unlock(&ec->lock);
 520        return 0;
 521}
 522
 523EXPORT_SYMBOL_GPL(acpi_ec_add_query_handler);
 524
 525void acpi_ec_remove_query_handler(struct acpi_ec *ec, u8 query_bit)
 526{
 527        struct acpi_ec_query_handler *handler, *tmp;
 528        mutex_lock(&ec->lock);
 529        list_for_each_entry_safe(handler, tmp, &ec->list, node) {
 530                if (query_bit == handler->query_bit) {
 531                        list_del(&handler->node);
 532                        kfree(handler);
 533                }
 534        }
 535        mutex_unlock(&ec->lock);
 536}
 537
 538EXPORT_SYMBOL_GPL(acpi_ec_remove_query_handler);
 539
 540static void acpi_ec_gpe_query(void *ec_cxt)
 541{
 542        struct acpi_ec *ec = ec_cxt;
 543        u8 value = 0;
 544        struct acpi_ec_query_handler *handler, copy;
 545
 546        if (!ec || acpi_ec_query(ec, &value))
 547                return;
 548        mutex_lock(&ec->lock);
 549        list_for_each_entry(handler, &ec->list, node) {
 550                if (value == handler->query_bit) {
 551                        /* have custom handler for this bit */
 552                        memcpy(&copy, handler, sizeof(copy));
 553                        mutex_unlock(&ec->lock);
 554                        if (copy.func) {
 555                                copy.func(copy.data);
 556                        } else if (copy.handle) {
 557                                acpi_evaluate_object(copy.handle, NULL, NULL, NULL);
 558                        }
 559                        return;
 560                }
 561        }
 562        mutex_unlock(&ec->lock);
 563}
 564
 565static u32 acpi_ec_gpe_handler(void *data)
 566{
 567        struct acpi_ec *ec = data;
 568        u8 status;
 569
 570        pr_debug(PREFIX "~~~> interrupt\n");
 571        status = acpi_ec_read_status(ec);
 572
 573        if (test_bit(EC_FLAGS_GPE_MODE, &ec->flags)) {
 574                gpe_transaction(ec, status);
 575                if (ec_transaction_done(ec) &&
 576                    (status & ACPI_EC_FLAG_IBF) == 0)
 577                        wake_up(&ec->wait);
 578        }
 579
 580        ec_check_sci(ec, status);
 581        if (!test_bit(EC_FLAGS_GPE_MODE, &ec->flags) &&
 582            !test_bit(EC_FLAGS_NO_GPE, &ec->flags)) {
 583                /* this is non-query, must be confirmation */
 584                if (!test_bit(EC_FLAGS_GPE_STORM, &ec->flags)) {
 585                        if (printk_ratelimit())
 586                                pr_info(PREFIX "non-query interrupt received,"
 587                                        " switching to interrupt mode\n");
 588                } else {
 589                        /* hush, STORM switches the mode every transaction */
 590                        pr_debug(PREFIX "non-query interrupt received,"
 591                                " switching to interrupt mode\n");
 592                }
 593                set_bit(EC_FLAGS_GPE_MODE, &ec->flags);
 594        }
 595        return ACPI_INTERRUPT_HANDLED;
 596}
 597
 598/* --------------------------------------------------------------------------
 599                             Address Space Management
 600   -------------------------------------------------------------------------- */
 601
 602static acpi_status
 603acpi_ec_space_handler(u32 function, acpi_physical_address address,
 604                      u32 bits, acpi_integer *value,
 605                      void *handler_context, void *region_context)
 606{
 607        struct acpi_ec *ec = handler_context;
 608        int result = 0, i;
 609        u8 temp = 0;
 610
 611        if ((address > 0xFF) || !value || !handler_context)
 612                return AE_BAD_PARAMETER;
 613
 614        if (function != ACPI_READ && function != ACPI_WRITE)
 615                return AE_BAD_PARAMETER;
 616
 617        if (bits != 8 && acpi_strict)
 618                return AE_BAD_PARAMETER;
 619
 620        acpi_ec_burst_enable(ec);
 621
 622        if (function == ACPI_READ) {
 623                result = acpi_ec_read(ec, address, &temp);
 624                *value = temp;
 625        } else {
 626                temp = 0xff & (*value);
 627                result = acpi_ec_write(ec, address, temp);
 628        }
 629
 630        for (i = 8; unlikely(bits - i > 0); i += 8) {
 631                ++address;
 632                if (function == ACPI_READ) {
 633                        result = acpi_ec_read(ec, address, &temp);
 634                        (*value) |= ((acpi_integer)temp) << i;
 635                } else {
 636                        temp = 0xff & ((*value) >> i);
 637                        result = acpi_ec_write(ec, address, temp);
 638                }
 639        }
 640
 641        acpi_ec_burst_disable(ec);
 642
 643        switch (result) {
 644        case -EINVAL:
 645                return AE_BAD_PARAMETER;
 646                break;
 647        case -ENODEV:
 648                return AE_NOT_FOUND;
 649                break;
 650        case -ETIME:
 651                return AE_TIME;
 652                break;
 653        default:
 654                return AE_OK;
 655        }
 656}
 657
 658/* --------------------------------------------------------------------------
 659                              FS Interface (/proc)
 660   -------------------------------------------------------------------------- */
 661
 662static struct proc_dir_entry *acpi_ec_dir;
 663
 664static int acpi_ec_read_info(struct seq_file *seq, void *offset)
 665{
 666        struct acpi_ec *ec = seq->private;
 667
 668        if (!ec)
 669                goto end;
 670
 671        seq_printf(seq, "gpe:\t\t\t0x%02x\n", (u32) ec->gpe);
 672        seq_printf(seq, "ports:\t\t\t0x%02x, 0x%02x\n",
 673                   (unsigned)ec->command_addr, (unsigned)ec->data_addr);
 674        seq_printf(seq, "use global lock:\t%s\n",
 675                   ec->global_lock ? "yes" : "no");
 676      end:
 677        return 0;
 678}
 679
 680static int acpi_ec_info_open_fs(struct inode *inode, struct file *file)
 681{
 682        return single_open(file, acpi_ec_read_info, PDE(inode)->data);
 683}
 684
 685static const struct file_operations acpi_ec_info_ops = {
 686        .open = acpi_ec_info_open_fs,
 687        .read = seq_read,
 688        .llseek = seq_lseek,
 689        .release = single_release,
 690        .owner = THIS_MODULE,
 691};
 692
 693static int acpi_ec_add_fs(struct acpi_device *device)
 694{
 695        struct proc_dir_entry *entry = NULL;
 696
 697        if (!acpi_device_dir(device)) {
 698                acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device),
 699                                                     acpi_ec_dir);
 700                if (!acpi_device_dir(device))
 701                        return -ENODEV;
 702        }
 703
 704        entry = proc_create_data(ACPI_EC_FILE_INFO, S_IRUGO,
 705                                 acpi_device_dir(device),
 706                                 &acpi_ec_info_ops, acpi_driver_data(device));
 707        if (!entry)
 708                return -ENODEV;
 709        return 0;
 710}
 711
 712static int acpi_ec_remove_fs(struct acpi_device *device)
 713{
 714
 715        if (acpi_device_dir(device)) {
 716                remove_proc_entry(ACPI_EC_FILE_INFO, acpi_device_dir(device));
 717                remove_proc_entry(acpi_device_bid(device), acpi_ec_dir);
 718                acpi_device_dir(device) = NULL;
 719        }
 720
 721        return 0;
 722}
 723
 724/* --------------------------------------------------------------------------
 725                               Driver Interface
 726   -------------------------------------------------------------------------- */
 727static acpi_status
 728ec_parse_io_ports(struct acpi_resource *resource, void *context);
 729
 730static struct acpi_ec *make_acpi_ec(void)
 731{
 732        struct acpi_ec *ec = kzalloc(sizeof(struct acpi_ec), GFP_KERNEL);
 733        if (!ec)
 734                return NULL;
 735        ec->flags = 1 << EC_FLAGS_QUERY_PENDING;
 736        mutex_init(&ec->lock);
 737        init_waitqueue_head(&ec->wait);
 738        INIT_LIST_HEAD(&ec->list);
 739        spin_lock_init(&ec->curr_lock);
 740        return ec;
 741}
 742
 743static acpi_status
 744acpi_ec_register_query_methods(acpi_handle handle, u32 level,
 745                               void *context, void **return_value)
 746{
 747        char node_name[5];
 748        struct acpi_buffer buffer = { sizeof(node_name), node_name };
 749        struct acpi_ec *ec = context;
 750        int value = 0;
 751        acpi_status status;
 752
 753        status = acpi_get_name(handle, ACPI_SINGLE_NAME, &buffer);
 754
 755        if (ACPI_SUCCESS(status) && sscanf(node_name, "_Q%x", &value) == 1) {
 756                acpi_ec_add_query_handler(ec, value, handle, NULL, NULL);
 757        }
 758        return AE_OK;
 759}
 760
 761static acpi_status
 762ec_parse_device(acpi_handle handle, u32 Level, void *context, void **retval)
 763{
 764        acpi_status status;
 765        unsigned long long tmp = 0;
 766
 767        struct acpi_ec *ec = context;
 768
 769        /* clear addr values, ec_parse_io_ports depend on it */
 770        ec->command_addr = ec->data_addr = 0;
 771
 772        status = acpi_walk_resources(handle, METHOD_NAME__CRS,
 773                                     ec_parse_io_ports, ec);
 774        if (ACPI_FAILURE(status))
 775                return status;
 776
 777        /* Get GPE bit assignment (EC events). */
 778        /* TODO: Add support for _GPE returning a package */
 779        status = acpi_evaluate_integer(handle, "_GPE", NULL, &tmp);
 780        if (ACPI_FAILURE(status))
 781                return status;
 782        ec->gpe = tmp;
 783        /* Use the global lock for all EC transactions? */
 784        tmp = 0;
 785        acpi_evaluate_integer(handle, "_GLK", NULL, &tmp);
 786        ec->global_lock = tmp;
 787        ec->handle = handle;
 788        return AE_CTRL_TERMINATE;
 789}
 790
 791static void ec_remove_handlers(struct acpi_ec *ec)
 792{
 793        if (ACPI_FAILURE(acpi_remove_address_space_handler(ec->handle,
 794                                ACPI_ADR_SPACE_EC, &acpi_ec_space_handler)))
 795                pr_err(PREFIX "failed to remove space handler\n");
 796        if (ACPI_FAILURE(acpi_remove_gpe_handler(NULL, ec->gpe,
 797                                &acpi_ec_gpe_handler)))
 798                pr_err(PREFIX "failed to remove gpe handler\n");
 799        clear_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags);
 800}
 801
 802static int acpi_ec_add(struct acpi_device *device)
 803{
 804        struct acpi_ec *ec = NULL;
 805
 806        if (!device)
 807                return -EINVAL;
 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        ec->handle = device->handle;
 829
 830        /* Find and register all query methods */
 831        acpi_walk_namespace(ACPI_TYPE_METHOD, ec->handle, 1,
 832                            acpi_ec_register_query_methods, ec, NULL);
 833
 834        if (!first_ec)
 835                first_ec = ec;
 836        device->driver_data = ec;
 837        acpi_ec_add_fs(device);
 838        pr_info(PREFIX "GPE = 0x%lx, I/O: command/status = 0x%lx, data = 0x%lx\n",
 839                          ec->gpe, ec->command_addr, ec->data_addr);
 840        pr_info(PREFIX "driver started in %s mode\n",
 841                (test_bit(EC_FLAGS_GPE_MODE, &ec->flags))?"interrupt":"poll");
 842        return 0;
 843}
 844
 845static int acpi_ec_remove(struct acpi_device *device, int type)
 846{
 847        struct acpi_ec *ec;
 848        struct acpi_ec_query_handler *handler, *tmp;
 849
 850        if (!device)
 851                return -EINVAL;
 852
 853        ec = acpi_driver_data(device);
 854        mutex_lock(&ec->lock);
 855        list_for_each_entry_safe(handler, tmp, &ec->list, node) {
 856                list_del(&handler->node);
 857                kfree(handler);
 858        }
 859        mutex_unlock(&ec->lock);
 860        acpi_ec_remove_fs(device);
 861        device->driver_data = NULL;
 862        if (ec == first_ec)
 863                first_ec = NULL;
 864        kfree(ec);
 865        return 0;
 866}
 867
 868static acpi_status
 869ec_parse_io_ports(struct acpi_resource *resource, void *context)
 870{
 871        struct acpi_ec *ec = context;
 872
 873        if (resource->type != ACPI_RESOURCE_TYPE_IO)
 874                return AE_OK;
 875
 876        /*
 877         * The first address region returned is the data port, and
 878         * the second address region returned is the status/command
 879         * port.
 880         */
 881        if (ec->data_addr == 0)
 882                ec->data_addr = resource->data.io.minimum;
 883        else if (ec->command_addr == 0)
 884                ec->command_addr = resource->data.io.minimum;
 885        else
 886                return AE_CTRL_TERMINATE;
 887
 888        return AE_OK;
 889}
 890
 891static int ec_install_handlers(struct acpi_ec *ec)
 892{
 893        acpi_status status;
 894        if (test_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags))
 895                return 0;
 896        status = acpi_install_gpe_handler(NULL, ec->gpe,
 897                                  ACPI_GPE_EDGE_TRIGGERED,
 898                                  &acpi_ec_gpe_handler, ec);
 899        if (ACPI_FAILURE(status))
 900                return -ENODEV;
 901        acpi_set_gpe_type(NULL, ec->gpe, ACPI_GPE_TYPE_RUNTIME);
 902        acpi_enable_gpe(NULL, ec->gpe);
 903        status = acpi_install_address_space_handler(ec->handle,
 904                                                    ACPI_ADR_SPACE_EC,
 905                                                    &acpi_ec_space_handler,
 906                                                    NULL, ec);
 907        if (ACPI_FAILURE(status)) {
 908                if (status == AE_NOT_FOUND) {
 909                        /*
 910                         * Maybe OS fails in evaluating the _REG object.
 911                         * The AE_NOT_FOUND error will be ignored and OS
 912                         * continue to initialize EC.
 913                         */
 914                        printk(KERN_ERR "Fail in evaluating the _REG object"
 915                                " of EC device. Broken bios is suspected.\n");
 916                } else {
 917                        acpi_remove_gpe_handler(NULL, ec->gpe,
 918                                &acpi_ec_gpe_handler);
 919                        return -ENODEV;
 920                }
 921        }
 922
 923        set_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags);
 924        return 0;
 925}
 926
 927static int acpi_ec_start(struct acpi_device *device)
 928{
 929        struct acpi_ec *ec;
 930        int ret = 0;
 931
 932        if (!device)
 933                return -EINVAL;
 934
 935        ec = acpi_driver_data(device);
 936
 937        if (!ec)
 938                return -EINVAL;
 939
 940        ret = ec_install_handlers(ec);
 941
 942        /* EC is fully operational, allow queries */
 943        clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags);
 944        return ret;
 945}
 946
 947static int acpi_ec_stop(struct acpi_device *device, int type)
 948{
 949        struct acpi_ec *ec;
 950        if (!device)
 951                return -EINVAL;
 952        ec = acpi_driver_data(device);
 953        if (!ec)
 954                return -EINVAL;
 955        ec_remove_handlers(ec);
 956
 957        return 0;
 958}
 959
 960int __init acpi_boot_ec_enable(void)
 961{
 962        if (!boot_ec || test_bit(EC_FLAGS_HANDLERS_INSTALLED, &boot_ec->flags))
 963                return 0;
 964        if (!ec_install_handlers(boot_ec)) {
 965                first_ec = boot_ec;
 966                return 0;
 967        }
 968        return -EFAULT;
 969}
 970
 971static const struct acpi_device_id ec_device_ids[] = {
 972        {"PNP0C09", 0},
 973        {"", 0},
 974};
 975
 976int __init acpi_ec_ecdt_probe(void)
 977{
 978        acpi_status status;
 979        struct acpi_ec *saved_ec = NULL;
 980        struct acpi_table_ecdt *ecdt_ptr;
 981
 982        boot_ec = make_acpi_ec();
 983        if (!boot_ec)
 984                return -ENOMEM;
 985        /*
 986         * Generate a boot ec context
 987         */
 988        if (dmi_name_in_vendors("Micro-Star") ||
 989            dmi_name_in_vendors("Notebook")) {
 990                pr_info(PREFIX "Enabling special treatment for EC from MSI.\n");
 991                EC_FLAGS_MSI = 1;
 992        }
 993        status = acpi_get_table(ACPI_SIG_ECDT, 1,
 994                                (struct acpi_table_header **)&ecdt_ptr);
 995        if (ACPI_SUCCESS(status)) {
 996                pr_info(PREFIX "EC description table is found, configuring boot EC\n");
 997                boot_ec->command_addr = ecdt_ptr->control.address;
 998                boot_ec->data_addr = ecdt_ptr->data.address;
 999                boot_ec->gpe = ecdt_ptr->gpe;
1000                boot_ec->handle = ACPI_ROOT_OBJECT;
1001                acpi_get_handle(ACPI_ROOT_OBJECT, ecdt_ptr->id, &boot_ec->handle);
1002                /* Don't trust ECDT, which comes from ASUSTek */
1003                if (!dmi_name_in_vendors("ASUS") && EC_FLAGS_MSI == 0)
1004                        goto install;
1005                saved_ec = kmalloc(sizeof(struct acpi_ec), GFP_KERNEL);
1006                if (!saved_ec)
1007                        return -ENOMEM;
1008                memcpy(saved_ec, boot_ec, sizeof(struct acpi_ec));
1009        /* fall through */
1010        }
1011        /* This workaround is needed only on some broken machines,
1012         * which require early EC, but fail to provide ECDT */
1013        printk(KERN_DEBUG PREFIX "Look up EC in DSDT\n");
1014        status = acpi_get_devices(ec_device_ids[0].id, ec_parse_device,
1015                                        boot_ec, NULL);
1016        /* Check that acpi_get_devices actually find something */
1017        if (ACPI_FAILURE(status) || !boot_ec->handle)
1018                goto error;
1019        if (saved_ec) {
1020                /* try to find good ECDT from ASUSTek */
1021                if (saved_ec->command_addr != boot_ec->command_addr ||
1022                    saved_ec->data_addr != boot_ec->data_addr ||
1023                    saved_ec->gpe != boot_ec->gpe ||
1024                    saved_ec->handle != boot_ec->handle)
1025                        pr_info(PREFIX "ASUSTek keeps feeding us with broken "
1026                        "ECDT tables, which are very hard to workaround. "
1027                        "Trying to use DSDT EC info instead. Please send "
1028                        "output of acpidump to linux-acpi@vger.kernel.org\n");
1029                kfree(saved_ec);
1030                saved_ec = NULL;
1031        } else {
1032                /* We really need to limit this workaround, the only ASUS,
1033                * which needs it, has fake EC._INI method, so use it as flag.
1034                * Keep boot_ec struct as it will be needed soon.
1035                */
1036                acpi_handle dummy;
1037                if (!dmi_name_in_vendors("ASUS") ||
1038                    ACPI_FAILURE(acpi_get_handle(boot_ec->handle, "_INI",
1039                                                        &dummy)))
1040                        return -ENODEV;
1041        }
1042install:
1043        if (!ec_install_handlers(boot_ec)) {
1044                first_ec = boot_ec;
1045                return 0;
1046        }
1047error:
1048        kfree(boot_ec);
1049        boot_ec = NULL;
1050        return -ENODEV;
1051}
1052
1053static int acpi_ec_suspend(struct acpi_device *device, pm_message_t state)
1054{
1055        struct acpi_ec *ec = acpi_driver_data(device);
1056        /* Stop using GPE */
1057        set_bit(EC_FLAGS_NO_GPE, &ec->flags);
1058        clear_bit(EC_FLAGS_GPE_MODE, &ec->flags);
1059        acpi_disable_gpe(NULL, ec->gpe);
1060        return 0;
1061}
1062
1063static int acpi_ec_resume(struct acpi_device *device)
1064{
1065        struct acpi_ec *ec = acpi_driver_data(device);
1066        /* Enable use of GPE back */
1067        clear_bit(EC_FLAGS_NO_GPE, &ec->flags);
1068        set_bit(EC_FLAGS_GPE_MODE, &ec->flags);
1069        acpi_enable_gpe(NULL, ec->gpe);
1070        return 0;
1071}
1072
1073static struct acpi_driver acpi_ec_driver = {
1074        .name = "ec",
1075        .class = ACPI_EC_CLASS,
1076        .ids = ec_device_ids,
1077        .ops = {
1078                .add = acpi_ec_add,
1079                .remove = acpi_ec_remove,
1080                .start = acpi_ec_start,
1081                .stop = acpi_ec_stop,
1082                .suspend = acpi_ec_suspend,
1083                .resume = acpi_ec_resume,
1084                },
1085};
1086
1087int __init acpi_ec_init(void)
1088{
1089        int result = 0;
1090
1091        acpi_ec_dir = proc_mkdir(ACPI_EC_CLASS, acpi_root_dir);
1092        if (!acpi_ec_dir)
1093                return -ENODEV;
1094
1095        /* Now register the driver for the EC */
1096        result = acpi_bus_register_driver(&acpi_ec_driver);
1097        if (result < 0) {
1098                remove_proc_entry(ACPI_EC_CLASS, acpi_root_dir);
1099                return -ENODEV;
1100        }
1101
1102        return result;
1103}
1104
1105/* EC driver currently not unloadable */
1106#if 0
1107static void __exit acpi_ec_exit(void)
1108{
1109
1110        acpi_bus_unregister_driver(&acpi_ec_driver);
1111
1112        remove_proc_entry(ACPI_EC_CLASS, acpi_root_dir);
1113
1114        return;
1115}
1116#endif  /* 0 */
1117