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/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 #include <acpi/actypes.h>
  46
  47 #define ACPI_EC_CLASS                   "embedded_controller"
  48 #define ACPI_EC_DEVICE_NAME             "Embedded Controller"
  49 #define ACPI_EC_FILE_INFO               "info"
  50
  51 #undef PREFIX
  52 #define PREFIX                          "ACPI: EC: "
  53
  54 /* EC status register */
  55 #define ACPI_EC_FLAG_OBF        0x01    /* Output buffer full */
  56 #define ACPI_EC_FLAG_IBF        0x02    /* Input buffer full */
  57 #define ACPI_EC_FLAG_BURST      0x10    /* burst mode */
  58 #define ACPI_EC_FLAG_SCI        0x20    /* EC-SCI occurred */
  59
  60 /* EC commands */
  61 enum ec_command {
  62         ACPI_EC_COMMAND_READ = 0x80,
  63         ACPI_EC_COMMAND_WRITE = 0x81,
  64         ACPI_EC_BURST_ENABLE = 0x82,
  65         ACPI_EC_BURST_DISABLE = 0x83,
  66         ACPI_EC_COMMAND_QUERY = 0x84,
  67 };
  68
  69 #define ACPI_EC_DELAY           500     /* Wait 500ms max. during EC ops */
  70 #define ACPI_EC_UDELAY_GLK      1000    /* Wait 1ms max. to get global lock */
  71 #define ACPI_EC_UDELAY          100     /* Wait 100us before polling EC again */
  72
  73 #define ACPI_EC_STORM_THRESHOLD 20      /* number of false interrupts
  74                                            per one transaction */
  75
  76 enum {
  77         EC_FLAGS_QUERY_PENDING,         /* Query is pending */
  78         EC_FLAGS_GPE_MODE,              /* Expect GPE to be sent
  79                                          * for status change */
  80         EC_FLAGS_NO_GPE,                /* Don't use GPE mode */
  81         EC_FLAGS_GPE_STORM,             /* GPE storm detected */
  82         EC_FLAGS_HANDLERS_INSTALLED     /* Handlers for GPE and
  83                                          * OpReg are installed */
  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_data {
  99         const u8 *wdata;
 100         u8 *rdata;
 101         unsigned short irq_count;
 102         u8 wlen;
 103         u8 rlen;
 104 };
 105
 106 static struct acpi_ec {
 107         acpi_handle handle;
 108         unsigned long gpe;
 109         unsigned long command_addr;
 110         unsigned long data_addr;
 111         unsigned long global_lock;
 112         unsigned long flags;
 113         struct mutex lock;
 114         wait_queue_head_t wait;
 115         struct list_head list;
 116         struct transaction_data *t;
 117         spinlock_t t_lock;
 118 } *boot_ec, *first_ec;
 119
 120 /*
 121  * Some Asus system have exchanged ECDT data/command IO addresses.
 122  */
 123 static int print_ecdt_error(const struct dmi_system_id *id)
 124 {
 125         printk(KERN_NOTICE PREFIX "%s detected - "
 126                 "ECDT has exchanged control/data I/O address\n",
 127                 id->ident);
 128         return 0;
 129 }
 130
 131 static struct dmi_system_id __cpuinitdata ec_dmi_table[] = {
 132         {
 133         print_ecdt_error, "Asus L4R", {
 134         DMI_MATCH(DMI_BIOS_VERSION, "1008.006"),
 135         DMI_MATCH(DMI_PRODUCT_NAME, "L4R"),
 136         DMI_MATCH(DMI_BOARD_NAME, "L4R") }, NULL},
 137         {
 138         print_ecdt_error, "Asus M6R", {
 139         DMI_MATCH(DMI_BIOS_VERSION, "0207"),
 140         DMI_MATCH(DMI_PRODUCT_NAME, "M6R"),
 141         DMI_MATCH(DMI_BOARD_NAME, "M6R") }, NULL},
 142         {},
 143 };
 144
 145 /* --------------------------------------------------------------------------
 146                              Transaction Management
 147    -------------------------------------------------------------------------- */
 148
 149 static inline u8 acpi_ec_read_status(struct acpi_ec *ec)
 150 {
 151         u8 x = inb(ec->command_addr);
 152         pr_debug(PREFIX "---> status = 0x%2.2x\n", x);
 153         return x;
 154 }
 155
 156 static inline u8 acpi_ec_read_data(struct acpi_ec *ec)
 157 {
 158         u8 x = inb(ec->data_addr);
 159         pr_debug(PREFIX "---> data = 0x%2.2x\n", x);
 160         return x;
 161 }
 162
 163 static inline void acpi_ec_write_cmd(struct acpi_ec *ec, u8 command)
 164 {
 165         pr_debug(PREFIX "<--- command = 0x%2.2x\n", command);
 166         outb(command, ec->command_addr);
 167 }
 168
 169 static inline void acpi_ec_write_data(struct acpi_ec *ec, u8 data)
 170 {
 171         pr_debug(PREFIX "<--- data = 0x%2.2x\n", data);
 172         outb(data, ec->data_addr);
 173 }
 174
 175 static int ec_transaction_done(struct acpi_ec *ec)
 176 {
 177         unsigned long flags;
 178         int ret = 0;
 179         spin_lock_irqsave(&ec->t_lock, flags);
 180         if (!ec->t || (!ec->t->wlen && !ec->t->rlen))
 181                 ret = 1;
 182         spin_unlock_irqrestore(&ec->t_lock, flags);
 183         return ret;
 184 }
 185
 186 static void gpe_transaction(struct acpi_ec *ec, u8 status)
 187 {
 188         unsigned long flags;
 189         spin_lock_irqsave(&ec->t_lock, flags);
 190         if (!ec->t)
 191                 goto unlock;
 192         if (ec->t->wlen > 0) {
 193                 if ((status & ACPI_EC_FLAG_IBF) == 0) {
 194                         acpi_ec_write_data(ec, *(ec->t->wdata++));
 195                         --ec->t->wlen;
 196                 } else
 197                         /* false interrupt, state didn't change */
 198                         ++ec->t->irq_count;
 199
 200         } else if (ec->t->rlen > 0) {
 201                 if ((status & ACPI_EC_FLAG_OBF) == 1) {
 202                         *(ec->t->rdata++) = acpi_ec_read_data(ec);
 203                         --ec->t->rlen;
 204                 } else
 205                         /* false interrupt, state didn't change */
 206                         ++ec->t->irq_count;
 207         }
 208 unlock:
 209         spin_unlock_irqrestore(&ec->t_lock, flags);
 210 }
 211
 212 static int acpi_ec_wait(struct acpi_ec *ec)
 213 {
 214         if (wait_event_timeout(ec->wait, ec_transaction_done(ec),
 215                                msecs_to_jiffies(ACPI_EC_DELAY)))
 216                 return 0;
 217         /* missing GPEs, switch back to poll mode */
 218         if (printk_ratelimit())
 219                 pr_info(PREFIX "missing confirmations, "
 220                                 "switch off interrupt mode.\n");
 221         set_bit(EC_FLAGS_NO_GPE, &ec->flags);
 222         clear_bit(EC_FLAGS_GPE_MODE, &ec->flags);
 223         return 1;
 224 }
 225
 226 static void acpi_ec_gpe_query(void *ec_cxt);
 227
 228 static int ec_check_sci(struct acpi_ec *ec, u8 state)
 229 {
 230         if (state & ACPI_EC_FLAG_SCI) {
 231                 if (!test_and_set_bit(EC_FLAGS_QUERY_PENDING, &ec->flags))
 232                         return acpi_os_execute(OSL_EC_BURST_HANDLER,
 233                                 acpi_ec_gpe_query, ec);
 234         }
 235         return 0;
 236 }
 237
 238 static int ec_poll(struct acpi_ec *ec)
 239 {
 240         unsigned long delay = jiffies + msecs_to_jiffies(ACPI_EC_DELAY);
 241         msleep(1);
 242         while (time_before(jiffies, delay)) {
 243                 gpe_transaction(ec, acpi_ec_read_status(ec));
 244                 msleep(1);
 245                 if (ec_transaction_done(ec))
 246                         return 0;
 247         }
 248         return -ETIME;
 249 }
 250
 251 static int acpi_ec_transaction_unlocked(struct acpi_ec *ec, u8 command,
 252                                         const u8 * wdata, unsigned wdata_len,
 253                                         u8 * rdata, unsigned rdata_len,
 254                                         int force_poll)
 255 {
 256         unsigned long tmp;
 257         struct transaction_data t = {.wdata = wdata, .rdata = rdata,
 258                                      .wlen = wdata_len, .rlen = rdata_len,
 259                                      .irq_count = 0};
 260         int ret = 0;
 261         pr_debug(PREFIX "transaction start\n");
 262         /* disable GPE during transaction if storm is detected */
 263         if (test_bit(EC_FLAGS_GPE_STORM, &ec->flags)) {
 264                 clear_bit(EC_FLAGS_GPE_MODE, &ec->flags);
 265                 acpi_disable_gpe(NULL, ec->gpe, ACPI_NOT_ISR);
 266         }
 267         /* start transaction */
 268         spin_lock_irqsave(&ec->t_lock, tmp);
 269         /* following two actions should be kept atomic */
 270         ec->t = &t;
 271         acpi_ec_write_cmd(ec, command);
 272         if (command == ACPI_EC_COMMAND_QUERY)
 273                 clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags);
 274         spin_unlock_irqrestore(&ec->t_lock, tmp);
 275         /* if we selected poll mode or failed in GPE-mode do a poll loop */
 276         if (force_poll ||
 277             !test_bit(EC_FLAGS_GPE_MODE, &ec->flags) ||
 278             acpi_ec_wait(ec))
 279                 ret = ec_poll(ec);
 280         pr_debug(PREFIX "transaction end\n");
 281         spin_lock_irqsave(&ec->t_lock, tmp);
 282         ec->t = NULL;
 283         spin_unlock_irqrestore(&ec->t_lock, tmp);
 284         if (test_bit(EC_FLAGS_GPE_STORM, &ec->flags)) {
 285                 /* check if we received SCI during transaction */
 286                 ec_check_sci(ec, acpi_ec_read_status(ec));
 287                 /* it is safe to enable GPE outside of transaction */
 288                 acpi_enable_gpe(NULL, ec->gpe, ACPI_NOT_ISR);
 289         } else if (test_bit(EC_FLAGS_GPE_MODE, &ec->flags) &&
 290                    t.irq_count > ACPI_EC_STORM_THRESHOLD) {
 291                 pr_debug(PREFIX "GPE storm detected\n");
 292                 set_bit(EC_FLAGS_GPE_STORM, &ec->flags);
 293         }
 294         return ret;
 295 }
 296
 297 static int ec_check_ibf0(struct acpi_ec *ec)
 298 {
 299         u8 status = acpi_ec_read_status(ec);
 300         return (status & ACPI_EC_FLAG_IBF) == 0;
 301 }
 302
 303 static int acpi_ec_transaction(struct acpi_ec *ec, u8 command,
 304                                const u8 * wdata, unsigned wdata_len,
 305                                u8 * rdata, unsigned rdata_len,
 306                                int force_poll)
 307 {
 308         int status;
 309         u32 glk;
 310         if (!ec || (wdata_len && !wdata) || (rdata_len && !rdata))
 311                 return -EINVAL;
 312         if (rdata)
 313                 memset(rdata, 0, rdata_len);
 314         mutex_lock(&ec->lock);
 315         if (ec->global_lock) {
 316                 status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk);
 317                 if (ACPI_FAILURE(status)) {
 318                         status = -ENODEV;
 319                         goto unlock;
 320                 }
 321         }
 322         if (!wait_event_timeout(ec->wait, ec_check_ibf0(ec),
 323                                 msecs_to_jiffies(ACPI_EC_DELAY))) {
 324                 pr_err(PREFIX "input buffer is not empty, "
 325                                 "aborting transaction\n");
 326                 status = -ETIME;
 327                 goto end;
 328         }
 329         status = acpi_ec_transaction_unlocked(ec, command,
 330                                               wdata, wdata_len,
 331                                               rdata, rdata_len,
 332                                               force_poll);
 333 end:
 334         if (ec->global_lock)
 335                 acpi_release_global_lock(glk);
 336 unlock:
 337         mutex_unlock(&ec->lock);
 338         return status;
 339 }
 340
 341 /*
 342  * Note: samsung nv5000 doesn't work with ec burst mode.
 343  * http://bugzilla.kernel.org/show_bug.cgi?id=4980
 344  */
 345 int acpi_ec_burst_enable(struct acpi_ec *ec)
 346 {
 347         u8 d;
 348         return acpi_ec_transaction(ec, ACPI_EC_BURST_ENABLE, NULL, 0, &d, 1, 0);
 349 }
 350
 351 int acpi_ec_burst_disable(struct acpi_ec *ec)
 352 {
 353         return (acpi_ec_read_status(ec) & ACPI_EC_FLAG_BURST) ?
 354                 acpi_ec_transaction(ec, ACPI_EC_BURST_DISABLE,
 355                         NULL, 0, NULL, 0, 0) : 0;
 356 }
 357
 358 static int acpi_ec_read(struct acpi_ec *ec, u8 address, u8 * data)
 359 {
 360         int result;
 361         u8 d;
 362
 363         result = acpi_ec_transaction(ec, ACPI_EC_COMMAND_READ,
 364                                      &address, 1, &d, 1, 0);
 365         *data = d;
 366         return result;
 367 }
 368
 369 static int acpi_ec_write(struct acpi_ec *ec, u8 address, u8 data)
 370 {
 371         u8 wdata[2] = { address, data };
 372         return acpi_ec_transaction(ec, ACPI_EC_COMMAND_WRITE,
 373                                    wdata, 2, NULL, 0, 0);
 374 }
 375
 376 /*
 377  * Externally callable EC access functions. For now, assume 1 EC only
 378  */
 379 int ec_burst_enable(void)
 380 {
 381         if (!first_ec)
 382                 return -ENODEV;
 383         return acpi_ec_burst_enable(first_ec);
 384 }
 385
 386 EXPORT_SYMBOL(ec_burst_enable);
 387
 388 int ec_burst_disable(void)
 389 {
 390         if (!first_ec)
 391                 return -ENODEV;
 392         return acpi_ec_burst_disable(first_ec);
 393 }
 394
 395 EXPORT_SYMBOL(ec_burst_disable);
 396
 397 int ec_read(u8 addr, u8 * val)
 398 {
 399         int err;
 400         u8 temp_data;
 401
 402         if (!first_ec)
 403                 return -ENODEV;
 404
 405         err = acpi_ec_read(first_ec, addr, &temp_data);
 406
 407         if (!err) {
 408                 *val = temp_data;
 409                 return 0;
 410         } else
 411                 return err;
 412 }
 413
 414 EXPORT_SYMBOL(ec_read);
 415
 416 int ec_write(u8 addr, u8 val)
 417 {
 418         int err;
 419
 420         if (!first_ec)
 421                 return -ENODEV;
 422
 423         err = acpi_ec_write(first_ec, addr, val);
 424
 425         return err;
 426 }
 427
 428 EXPORT_SYMBOL(ec_write);
 429
 430 int ec_transaction(u8 command,
 431                    const u8 * wdata, unsigned wdata_len,
 432                    u8 * rdata, unsigned rdata_len,
 433                    int force_poll)
 434 {
 435         if (!first_ec)
 436                 return -ENODEV;
 437
 438         return acpi_ec_transaction(first_ec, command, wdata,
 439                                    wdata_len, rdata, rdata_len,
 440                                    force_poll);
 441 }
 442
 443 EXPORT_SYMBOL(ec_transaction);
 444
 445 static int acpi_ec_query(struct acpi_ec *ec, u8 * data)
 446 {
 447         int result;
 448         u8 d;
 449
 450         if (!ec || !data)
 451                 return -EINVAL;
 452
 453         /*
 454          * Query the EC to find out which _Qxx method we need to evaluate.
 455          * Note that successful completion of the query causes the ACPI_EC_SCI
 456          * bit to be cleared (and thus clearing the interrupt source).
 457          */
 458
 459         result = acpi_ec_transaction(ec, ACPI_EC_COMMAND_QUERY, NULL, 0, &d, 1, 0);
 460         if (result)
 461                 return result;
 462
 463         if (!d)
 464                 return -ENODATA;
 465
 466         *data = d;
 467         return 0;
 468 }
 469
 470 /* --------------------------------------------------------------------------
 471                                 Event Management
 472    -------------------------------------------------------------------------- */
 473 int acpi_ec_add_query_handler(struct acpi_ec *ec, u8 query_bit,
 474                               acpi_handle handle, acpi_ec_query_func func,
 475                               void *data)
 476 {
 477         struct acpi_ec_query_handler *handler =
 478             kzalloc(sizeof(struct acpi_ec_query_handler), GFP_KERNEL);
 479         if (!handler)
 480                 return -ENOMEM;
 481
 482         handler->query_bit = query_bit;
 483         handler->handle = handle;
 484         handler->func = func;
 485         handler->data = data;
 486         mutex_lock(&ec->lock);
 487         list_add(&handler->node, &ec->list);
 488         mutex_unlock(&ec->lock);
 489         return 0;
 490 }
 491
 492 EXPORT_SYMBOL_GPL(acpi_ec_add_query_handler);
 493
 494 void acpi_ec_remove_query_handler(struct acpi_ec *ec, u8 query_bit)
 495 {
 496         struct acpi_ec_query_handler *handler, *tmp;
 497         mutex_lock(&ec->lock);
 498         list_for_each_entry_safe(handler, tmp, &ec->list, node) {
 499                 if (query_bit == handler->query_bit) {
 500                         list_del(&handler->node);
 501                         kfree(handler);
 502                 }
 503         }
 504         mutex_unlock(&ec->lock);
 505 }
 506
 507 EXPORT_SYMBOL_GPL(acpi_ec_remove_query_handler);
 508
 509 static void acpi_ec_gpe_query(void *ec_cxt)
 510 {
 511         struct acpi_ec *ec = ec_cxt;
 512         u8 value = 0;
 513         struct acpi_ec_query_handler *handler, copy;
 514
 515         if (!ec || acpi_ec_query(ec, &value))
 516                 return;
 517         mutex_lock(&ec->lock);
 518         list_for_each_entry(handler, &ec->list, node) {
 519                 if (value == handler->query_bit) {
 520                         /* have custom handler for this bit */
 521                         memcpy(&copy, handler, sizeof(copy));
 522                         mutex_unlock(&ec->lock);
 523                         if (copy.func) {
 524                                 copy.func(copy.data);
 525                         } else if (copy.handle) {
 526                                 acpi_evaluate_object(copy.handle, NULL, NULL, NULL);
 527                         }
 528                         return;
 529                 }
 530         }
 531         mutex_unlock(&ec->lock);
 532 }
 533
 534 static u32 acpi_ec_gpe_handler(void *data)
 535 {
 536         struct acpi_ec *ec = data;
 537         u8 status;
 538
 539         pr_debug(PREFIX "~~~> interrupt\n");
 540         status = acpi_ec_read_status(ec);
 541
 542         gpe_transaction(ec, status);
 543         if (ec_transaction_done(ec) && (status & ACPI_EC_FLAG_IBF) == 0)
 544                 wake_up(&ec->wait);
 545
 546         ec_check_sci(ec, status);
 547         if (!test_bit(EC_FLAGS_GPE_MODE, &ec->flags) &&
 548             !test_bit(EC_FLAGS_NO_GPE, &ec->flags)) {
 549                 /* this is non-query, must be confirmation */
 550                 if (printk_ratelimit())
 551                         pr_info(PREFIX "non-query interrupt received,"
 552                                 " switching to interrupt mode\n");
 553                 set_bit(EC_FLAGS_GPE_MODE, &ec->flags);
 554         }
 555         return ACPI_INTERRUPT_HANDLED;
 556 }
 557
 558 /* --------------------------------------------------------------------------
 559                              Address Space Management
 560    -------------------------------------------------------------------------- */
 561
 562 static acpi_status
 563 acpi_ec_space_handler(u32 function, acpi_physical_address address,
 564                       u32 bits, acpi_integer *value,
 565                       void *handler_context, void *region_context)
 566 {
 567         struct acpi_ec *ec = handler_context;
 568         int result = 0, i;
 569         u8 temp = 0;
 570
 571         if ((address > 0xFF) || !value || !handler_context)
 572                 return AE_BAD_PARAMETER;
 573
 574         if (function != ACPI_READ && function != ACPI_WRITE)
 575                 return AE_BAD_PARAMETER;
 576
 577         if (bits != 8 && acpi_strict)
 578                 return AE_BAD_PARAMETER;
 579
 580         acpi_ec_burst_enable(ec);
 581
 582         if (function == ACPI_READ) {
 583                 result = acpi_ec_read(ec, address, &temp);
 584                 *value = temp;
 585         } else {
 586                 temp = 0xff & (*value);
 587                 result = acpi_ec_write(ec, address, temp);
 588         }
 589
 590         for (i = 8; unlikely(bits - i > 0); i += 8) {
 591                 ++address;
 592                 if (function == ACPI_READ) {
 593                         result = acpi_ec_read(ec, address, &temp);
 594                         (*value) |= ((acpi_integer)temp) << i;
 595                 } else {
 596                         temp = 0xff & ((*value) >> i);
 597                         result = acpi_ec_write(ec, address, temp);
 598                 }
 599         }
 600
 601         acpi_ec_burst_disable(ec);
 602
 603         switch (result) {
 604         case -EINVAL:
 605                 return AE_BAD_PARAMETER;
 606                 break;
 607         case -ENODEV:
 608                 return AE_NOT_FOUND;
 609                 break;
 610         case -ETIME:
 611                 return AE_TIME;
 612                 break;
 613         default:
 614                 return AE_OK;
 615         }
 616 }
 617
 618 /* --------------------------------------------------------------------------
 619                               FS Interface (/proc)
 620    -------------------------------------------------------------------------- */
 621
 622 static struct proc_dir_entry *acpi_ec_dir;
 623
 624 static int acpi_ec_read_info(struct seq_file *seq, void *offset)
 625 {
 626         struct acpi_ec *ec = seq->private;
 627
 628         if (!ec)
 629                 goto end;
 630
 631         seq_printf(seq, "gpe:\t\t\t0x%02x\n", (u32) ec->gpe);
 632         seq_printf(seq, "ports:\t\t\t0x%02x, 0x%02x\n",
 633                    (unsigned)ec->command_addr, (unsigned)ec->data_addr);
 634         seq_printf(seq, "use global lock:\t%s\n",
 635                    ec->global_lock ? "yes" : "no");
 636       end:
 637         return 0;
 638 }
 639
 640 static int acpi_ec_info_open_fs(struct inode *inode, struct file *file)
 641 {
 642         return single_open(file, acpi_ec_read_info, PDE(inode)->data);
 643 }
 644
 645 static struct file_operations acpi_ec_info_ops = {
 646         .open = acpi_ec_info_open_fs,
 647         .read = seq_read,
 648         .llseek = seq_lseek,
 649         .release = single_release,
 650         .owner = THIS_MODULE,
 651 };
 652
 653 static int acpi_ec_add_fs(struct acpi_device *device)
 654 {
 655         struct proc_dir_entry *entry = NULL;
 656
 657         if (!acpi_device_dir(device)) {
 658                 acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device),
 659                                                      acpi_ec_dir);
 660                 if (!acpi_device_dir(device))
 661                         return -ENODEV;
 662         }
 663
 664         entry = proc_create_data(ACPI_EC_FILE_INFO, S_IRUGO,
 665                                  acpi_device_dir(device),
 666                                  &acpi_ec_info_ops, acpi_driver_data(device));
 667         if (!entry)
 668                 return -ENODEV;
 669         return 0;
 670 }
 671
 672 static int acpi_ec_remove_fs(struct acpi_device *device)
 673 {
 674
 675         if (acpi_device_dir(device)) {
 676                 remove_proc_entry(ACPI_EC_FILE_INFO, acpi_device_dir(device));
 677                 remove_proc_entry(acpi_device_bid(device), acpi_ec_dir);
 678                 acpi_device_dir(device) = NULL;
 679         }
 680
 681         return 0;
 682 }
 683
 684 /* --------------------------------------------------------------------------
 685                                Driver Interface
 686    -------------------------------------------------------------------------- */
 687 static acpi_status
 688 ec_parse_io_ports(struct acpi_resource *resource, void *context);
 689
 690 static struct acpi_ec *make_acpi_ec(void)
 691 {
 692         struct acpi_ec *ec = kzalloc(sizeof(struct acpi_ec), GFP_KERNEL);
 693         if (!ec)
 694                 return NULL;
 695         ec->flags = 1 << EC_FLAGS_QUERY_PENDING;
 696         mutex_init(&ec->lock);
 697         init_waitqueue_head(&ec->wait);
 698         INIT_LIST_HEAD(&ec->list);
 699         spin_lock_init(&ec->t_lock);
 700         return ec;
 701 }
 702
 703 static acpi_status
 704 acpi_ec_register_query_methods(acpi_handle handle, u32 level,
 705                                void *context, void **return_value)
 706 {
 707         struct acpi_namespace_node *node = handle;
 708         struct acpi_ec *ec = context;
 709         int value = 0;
 710         if (sscanf(node->name.ascii, "_Q%x", &value) == 1) {
 711                 acpi_ec_add_query_handler(ec, value, handle, NULL, NULL);
 712         }
 713         return AE_OK;
 714 }
 715
 716 static acpi_status
 717 ec_parse_device(acpi_handle handle, u32 Level, void *context, void **retval)
 718 {
 719         acpi_status status;
 720
 721         struct acpi_ec *ec = context;
 722         status = acpi_walk_resources(handle, METHOD_NAME__CRS,
 723                                      ec_parse_io_ports, ec);
 724         if (ACPI_FAILURE(status))
 725                 return status;
 726
 727         /* Get GPE bit assignment (EC events). */
 728         /* TODO: Add support for _GPE returning a package */
 729         status = acpi_evaluate_integer(handle, "_GPE", NULL, &ec->gpe);
 730         if (ACPI_FAILURE(status))
 731                 return status;
 732         /* Use the global lock for all EC transactions? */
 733         acpi_evaluate_integer(handle, "_GLK", NULL, &ec->global_lock);
 734         ec->handle = handle;
 735         return AE_CTRL_TERMINATE;
 736 }
 737
 738 static void ec_remove_handlers(struct acpi_ec *ec)
 739 {
 740         if (ACPI_FAILURE(acpi_remove_address_space_handler(ec->handle,
 741                                 ACPI_ADR_SPACE_EC, &acpi_ec_space_handler)))
 742                 pr_err(PREFIX "failed to remove space handler\n");
 743         if (ACPI_FAILURE(acpi_remove_gpe_handler(NULL, ec->gpe,
 744                                 &acpi_ec_gpe_handler)))
 745                 pr_err(PREFIX "failed to remove gpe handler\n");
 746         clear_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags);
 747 }
 748
 749 static int acpi_ec_add(struct acpi_device *device)
 750 {
 751         struct acpi_ec *ec = NULL;
 752
 753         if (!device)
 754                 return -EINVAL;
 755         strcpy(acpi_device_name(device), ACPI_EC_DEVICE_NAME);
 756         strcpy(acpi_device_class(device), ACPI_EC_CLASS);
 757
 758         /* Check for boot EC */
 759         if (boot_ec &&
 760             (boot_ec->handle == device->handle ||
 761              boot_ec->handle == ACPI_ROOT_OBJECT)) {
 762                 ec = boot_ec;
 763                 boot_ec = NULL;
 764         } else {
 765                 ec = make_acpi_ec();
 766                 if (!ec)
 767                         return -ENOMEM;
 768                 if (ec_parse_device(device->handle, 0, ec, NULL) !=
 769                     AE_CTRL_TERMINATE) {
 770                         kfree(ec);
 771                         return -EINVAL;
 772                 }
 773         }
 774
 775         ec->handle = device->handle;
 776
 777         /* Find and register all query methods */
 778         acpi_walk_namespace(ACPI_TYPE_METHOD, ec->handle, 1,
 779                             acpi_ec_register_query_methods, ec, NULL);
 780
 781         if (!first_ec)
 782                 first_ec = ec;
 783         acpi_driver_data(device) = ec;
 784         acpi_ec_add_fs(device);
 785         pr_info(PREFIX "GPE = 0x%lx, I/O: command/status = 0x%lx, data = 0x%lx\n",
 786                           ec->gpe, ec->command_addr, ec->data_addr);
 787         pr_info(PREFIX "driver started in %s mode\n",
 788                 (test_bit(EC_FLAGS_GPE_MODE, &ec->flags))?"interrupt":"poll");
 789         return 0;
 790 }
 791
 792 static int acpi_ec_remove(struct acpi_device *device, int type)
 793 {
 794         struct acpi_ec *ec;
 795         struct acpi_ec_query_handler *handler, *tmp;
 796
 797         if (!device)
 798                 return -EINVAL;
 799
 800         ec = acpi_driver_data(device);
 801         mutex_lock(&ec->lock);
 802         list_for_each_entry_safe(handler, tmp, &ec->list, node) {
 803                 list_del(&handler->node);
 804                 kfree(handler);
 805         }
 806         mutex_unlock(&ec->lock);
 807         acpi_ec_remove_fs(device);
 808         acpi_driver_data(device) = NULL;
 809         if (ec == first_ec)
 810                 first_ec = NULL;
 811         kfree(ec);
 812         return 0;
 813 }
 814
 815 static acpi_status
 816 ec_parse_io_ports(struct acpi_resource *resource, void *context)
 817 {
 818         struct acpi_ec *ec = context;
 819
 820         if (resource->type != ACPI_RESOURCE_TYPE_IO)
 821                 return AE_OK;
 822
 823         /*
 824          * The first address region returned is the data port, and
 825          * the second address region returned is the status/command
 826          * port.
 827          */
 828         if (ec->data_addr == 0)
 829                 ec->data_addr = resource->data.io.minimum;
 830         else if (ec->command_addr == 0)
 831                 ec->command_addr = resource->data.io.minimum;
 832         else
 833                 return AE_CTRL_TERMINATE;
 834
 835         return AE_OK;
 836 }
 837
 838 static int ec_install_handlers(struct acpi_ec *ec)
 839 {
 840         acpi_status status;
 841         if (test_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags))
 842                 return 0;
 843         status = acpi_install_gpe_handler(NULL, ec->gpe,
 844                                   ACPI_GPE_EDGE_TRIGGERED,
 845                                   &acpi_ec_gpe_handler, ec);
 846         if (ACPI_FAILURE(status))
 847                 return -ENODEV;
 848         acpi_set_gpe_type(NULL, ec->gpe, ACPI_GPE_TYPE_RUNTIME);
 849         acpi_enable_gpe(NULL, ec->gpe, ACPI_NOT_ISR);
 850         status = acpi_install_address_space_handler(ec->handle,
 851                                                     ACPI_ADR_SPACE_EC,
 852                                                     &acpi_ec_space_handler,
 853                                                     NULL, ec);
 854         if (ACPI_FAILURE(status)) {
 855                 acpi_remove_gpe_handler(NULL, ec->gpe, &acpi_ec_gpe_handler);
 856                 return -ENODEV;
 857         }
 858
 859         set_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags);
 860         return 0;
 861 }
 862
 863 static int acpi_ec_start(struct acpi_device *device)
 864 {
 865         struct acpi_ec *ec;
 866         int ret = 0;
 867
 868         if (!device)
 869                 return -EINVAL;
 870
 871         ec = acpi_driver_data(device);
 872
 873         if (!ec)
 874                 return -EINVAL;
 875
 876         ret = ec_install_handlers(ec);
 877
 878         /* EC is fully operational, allow queries */
 879         clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags);
 880         return ret;
 881 }
 882
 883 static int acpi_ec_stop(struct acpi_device *device, int type)
 884 {
 885         struct acpi_ec *ec;
 886         if (!device)
 887                 return -EINVAL;
 888         ec = acpi_driver_data(device);
 889         if (!ec)
 890                 return -EINVAL;
 891         ec_remove_handlers(ec);
 892
 893         return 0;
 894 }
 895
 896 int __init acpi_boot_ec_enable(void)
 897 {
 898         if (!boot_ec || test_bit(EC_FLAGS_HANDLERS_INSTALLED, &boot_ec->flags))
 899                 return 0;
 900         if (!ec_install_handlers(boot_ec)) {
 901                 first_ec = boot_ec;
 902                 return 0;
 903         }
 904         return -EFAULT;
 905 }
 906
 907 static const struct acpi_device_id ec_device_ids[] = {
 908         {"PNP0C09", 0},
 909         {"", 0},
 910 };
 911
 912 int __init acpi_ec_ecdt_probe(void)
 913 {
 914         int ret;
 915         acpi_status status;
 916         struct acpi_table_ecdt *ecdt_ptr;
 917
 918         boot_ec = make_acpi_ec();
 919         if (!boot_ec)
 920                 return -ENOMEM;
 921         /*
 922          * Generate a boot ec context
 923          */
 924         status = acpi_get_table(ACPI_SIG_ECDT, 1,
 925                                 (struct acpi_table_header **)&ecdt_ptr);
 926         if (ACPI_SUCCESS(status)) {
 927                 pr_info(PREFIX "EC description table is found, configuring boot EC\n");
 928                 boot_ec->command_addr = ecdt_ptr->control.address;
 929                 boot_ec->data_addr = ecdt_ptr->data.address;
 930                 if (dmi_check_system(ec_dmi_table)) {
 931                         /*
 932                          * If the board falls into ec_dmi_table, it means
 933                          * that ECDT table gives the incorrect command/status
 934                          * & data I/O address. Just fix it.
 935                          */
 936                         boot_ec->data_addr = ecdt_ptr->control.address;
 937                         boot_ec->command_addr = ecdt_ptr->data.address;
 938                 }
 939                 boot_ec->gpe = ecdt_ptr->gpe;
 940                 boot_ec->handle = ACPI_ROOT_OBJECT;
 941                 acpi_get_handle(ACPI_ROOT_OBJECT, ecdt_ptr->id, &boot_ec->handle);
 942         } else {
 943                 /* This workaround is needed only on some broken machines,
 944                  * which require early EC, but fail to provide ECDT */
 945                 acpi_handle x;
 946                 printk(KERN_DEBUG PREFIX "Look up EC in DSDT\n");
 947                 status = acpi_get_devices(ec_device_ids[0].id, ec_parse_device,
 948                                                 boot_ec, NULL);
 949                 /* Check that acpi_get_devices actually find something */
 950                 if (ACPI_FAILURE(status) || !boot_ec->handle)
 951                         goto error;
 952                 /* We really need to limit this workaround, the only ASUS,
 953                  * which needs it, has fake EC._INI method, so use it as flag.
 954                  * Keep boot_ec struct as it will be needed soon.
 955                  */
 956                 if (ACPI_FAILURE(acpi_get_handle(boot_ec->handle, "_INI", &x)))
 957                         return -ENODEV;
 958         }
 959
 960         ret = ec_install_handlers(boot_ec);
 961         if (!ret) {
 962                 first_ec = boot_ec;
 963                 return 0;
 964         }
 965       error:
 966         kfree(boot_ec);
 967         boot_ec = NULL;
 968         return -ENODEV;
 969 }
 970
 971 static int acpi_ec_suspend(struct acpi_device *device, pm_message_t state)
 972 {
 973         struct acpi_ec *ec = acpi_driver_data(device);
 974         /* Stop using GPE */
 975         set_bit(EC_FLAGS_NO_GPE, &ec->flags);
 976         clear_bit(EC_FLAGS_GPE_MODE, &ec->flags);
 977         acpi_disable_gpe(NULL, ec->gpe, ACPI_NOT_ISR);
 978         return 0;
 979 }
 980
 981 static int acpi_ec_resume(struct acpi_device *device)
 982 {
 983         struct acpi_ec *ec = acpi_driver_data(device);
 984         /* Enable use of GPE back */
 985         clear_bit(EC_FLAGS_NO_GPE, &ec->flags);
 986         acpi_enable_gpe(NULL, ec->gpe, ACPI_NOT_ISR);
 987         return 0;
 988 }
 989
 990 static struct acpi_driver acpi_ec_driver = {
 991         .name = "ec",
 992         .class = ACPI_EC_CLASS,
 993         .ids = ec_device_ids,
 994         .ops = {
 995                 .add = acpi_ec_add,
 996                 .remove = acpi_ec_remove,
 997                 .start = acpi_ec_start,
 998                 .stop = acpi_ec_stop,
 999                 .suspend = acpi_ec_suspend,
1000                 .resume = acpi_ec_resume,
1001                 },
1002 };
1003
1004 static int __init acpi_ec_init(void)
1005 {
1006         int result = 0;
1007
1008         if (acpi_disabled)
1009                 return 0;
1010
1011         acpi_ec_dir = proc_mkdir(ACPI_EC_CLASS, acpi_root_dir);
1012         if (!acpi_ec_dir)
1013                 return -ENODEV;
1014
1015         /* Now register the driver for the EC */
1016         result = acpi_bus_register_driver(&acpi_ec_driver);
1017         if (result < 0) {
1018                 remove_proc_entry(ACPI_EC_CLASS, acpi_root_dir);
1019                 return -ENODEV;
1020         }
1021
1022         return result;
1023 }
1024
1025 subsys_initcall(acpi_ec_init);
1026
1027 /* EC driver currently not unloadable */
1028 #if 0
1029 static void __exit acpi_ec_exit(void)
1030 {
1031
1032         acpi_bus_unregister_driver(&acpi_ec_driver);
1033
1034         remove_proc_entry(ACPI_EC_CLASS, acpi_root_dir);
1035
1036         return;
1037 }
1038 #endif  /* 0 */