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 {
  99         const u8 *wdata;
 100         u8 *rdata;
 101         unsigned short irq_count;
 102         u8 command;
 103         u8 wlen;
 104         u8 rlen;
 105 };
 106
 107 static struct acpi_ec {
 108         acpi_handle handle;
 109         unsigned long gpe;
 110         unsigned long command_addr;
 111         unsigned long data_addr;
 112         unsigned long global_lock;
 113         unsigned long flags;
 114         struct mutex lock;
 115         wait_queue_head_t wait;
 116         struct list_head list;
 117         struct transaction *curr;
 118         spinlock_t curr_lock;
 119 } *boot_ec, *first_ec;
 120
 121 /*
 122  * Some Asus system have exchanged ECDT data/command IO addresses.
 123  */
 124 static int print_ecdt_error(const struct dmi_system_id *id)
 125 {
 126         printk(KERN_NOTICE PREFIX "%s detected - "
 127                 "ECDT has exchanged control/data I/O address\n",
 128                 id->ident);
 129         return 0;
 130 }
 131
 132 static struct dmi_system_id __cpuinitdata ec_dmi_table[] = {
 133         {
 134         print_ecdt_error, "Asus L4R", {
 135         DMI_MATCH(DMI_BIOS_VERSION, "1008.006"),
 136         DMI_MATCH(DMI_PRODUCT_NAME, "L4R"),
 137         DMI_MATCH(DMI_BOARD_NAME, "L4R") }, NULL},
 138         {
 139         print_ecdt_error, "Asus M6R", {
 140         DMI_MATCH(DMI_BIOS_VERSION, "0207"),
 141         DMI_MATCH(DMI_PRODUCT_NAME, "M6R"),
 142         DMI_MATCH(DMI_BOARD_NAME, "M6R") }, NULL},
 143         {},
 144 };
 145
 146 /* --------------------------------------------------------------------------
 147                              Transaction Management
 148    -------------------------------------------------------------------------- */
 149
 150 static inline u8 acpi_ec_read_status(struct acpi_ec *ec)
 151 {
 152         u8 x = inb(ec->command_addr);
 153         pr_debug(PREFIX "---> status = 0x%2.2x\n", x);
 154         return x;
 155 }
 156
 157 static inline u8 acpi_ec_read_data(struct acpi_ec *ec)
 158 {
 159         u8 x = inb(ec->data_addr);
 160         pr_debug(PREFIX "---> data = 0x%2.2x\n", x);
 161         return x;
 162 }
 163
 164 static inline void acpi_ec_write_cmd(struct acpi_ec *ec, u8 command)
 165 {
 166         pr_debug(PREFIX "<--- command = 0x%2.2x\n", command);
 167         outb(command, ec->command_addr);
 168 }
 169
 170 static inline void acpi_ec_write_data(struct acpi_ec *ec, u8 data)
 171 {
 172         pr_debug(PREFIX "<--- data = 0x%2.2x\n", data);
 173         outb(data, ec->data_addr);
 174 }
 175
 176 static int ec_transaction_done(struct acpi_ec *ec)
 177 {
 178         unsigned long flags;
 179         int ret = 0;
 180         spin_lock_irqsave(&ec->curr_lock, flags);
 181         if (!ec->curr || (!ec->curr->wlen && !ec->curr->rlen))
 182                 ret = 1;
 183         spin_unlock_irqrestore(&ec->curr_lock, flags);
 184         return ret;
 185 }
 186
 187 static void gpe_transaction(struct acpi_ec *ec, u8 status)
 188 {
 189         unsigned long flags;
 190         spin_lock_irqsave(&ec->curr_lock, flags);
 191         if (!ec->curr)
 192                 goto unlock;
 193         if (ec->curr->wlen > 0) {
 194                 if ((status & ACPI_EC_FLAG_IBF) == 0) {
 195                         acpi_ec_write_data(ec, *(ec->curr->wdata++));
 196                         --ec->curr->wlen;
 197                 } else
 198                         /* false interrupt, state didn't change */
 199                         ++ec->curr->irq_count;
 200
 201         } else if (ec->curr->rlen > 0) {
 202                 if ((status & ACPI_EC_FLAG_OBF) == 1) {
 203                         *(ec->curr->rdata++) = acpi_ec_read_data(ec);
 204                         --ec->curr->rlen;
 205                 } else
 206                         /* false interrupt, state didn't change */
 207                         ++ec->curr->irq_count;
 208         }
 209 unlock:
 210         spin_unlock_irqrestore(&ec->curr_lock, flags);
 211 }
 212
 213 static int acpi_ec_wait(struct acpi_ec *ec)
 214 {
 215         if (wait_event_timeout(ec->wait, ec_transaction_done(ec),
 216                                msecs_to_jiffies(ACPI_EC_DELAY)))
 217                 return 0;
 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
 227 static void acpi_ec_gpe_query(void *ec_cxt);
 228
 229 static 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
 239 static int ec_poll(struct acpi_ec *ec)
 240 {
 241         unsigned long delay = jiffies + msecs_to_jiffies(ACPI_EC_DELAY);
 242         msleep(1);
 243         while (time_before(jiffies, delay)) {
 244                 gpe_transaction(ec, acpi_ec_read_status(ec));
 245                 msleep(1);
 246                 if (ec_transaction_done(ec))
 247                         return 0;
 248         }
 249         return -ETIME;
 250 }
 251
 252 static int acpi_ec_transaction_unlocked(struct acpi_ec *ec,
 253                                         struct transaction *t,
 254                                         int force_poll)
 255 {
 256         unsigned long tmp;
 257         int ret = 0;
 258         pr_debug(PREFIX "transaction start\n");
 259         /* disable GPE during transaction if storm is detected */
 260         if (test_bit(EC_FLAGS_GPE_STORM, &ec->flags)) {
 261                 clear_bit(EC_FLAGS_GPE_MODE, &ec->flags);
 262                 acpi_disable_gpe(NULL, ec->gpe, ACPI_NOT_ISR);
 263         }
 264         /* start transaction */
 265         spin_lock_irqsave(&ec->curr_lock, tmp);
 266         /* following two actions should be kept atomic */
 267         t->irq_count = 0;
 268         ec->curr = t;
 269         acpi_ec_write_cmd(ec, ec->curr->command);
 270         if (ec->curr->command == ACPI_EC_COMMAND_QUERY)
 271                 clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags);
 272         spin_unlock_irqrestore(&ec->curr_lock, tmp);
 273         /* if we selected poll mode or failed in GPE-mode do a poll loop */
 274         if (force_poll ||
 275             !test_bit(EC_FLAGS_GPE_MODE, &ec->flags) ||
 276             acpi_ec_wait(ec))
 277                 ret = ec_poll(ec);
 278         pr_debug(PREFIX "transaction end\n");
 279         spin_lock_irqsave(&ec->curr_lock, tmp);
 280         ec->curr = NULL;
 281         spin_unlock_irqrestore(&ec->curr_lock, tmp);
 282         if (test_bit(EC_FLAGS_GPE_STORM, &ec->flags)) {
 283                 /* check if we received SCI during transaction */
 284                 ec_check_sci(ec, acpi_ec_read_status(ec));
 285                 /* it is safe to enable GPE outside of transaction */
 286                 acpi_enable_gpe(NULL, ec->gpe, ACPI_NOT_ISR);
 287         } else if (test_bit(EC_FLAGS_GPE_MODE, &ec->flags) &&
 288                    t->irq_count > ACPI_EC_STORM_THRESHOLD) {
 289                 pr_debug(PREFIX "GPE storm detected\n");
 290                 set_bit(EC_FLAGS_GPE_STORM, &ec->flags);
 291         }
 292         return ret;
 293 }
 294
 295 static int ec_check_ibf0(struct acpi_ec *ec)
 296 {
 297         u8 status = acpi_ec_read_status(ec);
 298         return (status & ACPI_EC_FLAG_IBF) == 0;
 299 }
 300
 301 static int acpi_ec_transaction(struct acpi_ec *ec, struct transaction *t,
 302                                int force_poll)
 303 {
 304         int status;
 305         u32 glk;
 306         if (!ec || (!t) || (t->wlen && !t->wdata) || (t->rlen && !t->rdata))
 307                 return -EINVAL;
 308         if (t->rdata)
 309                 memset(t->rdata, 0, t->rlen);
 310         mutex_lock(&ec->lock);
 311         if (ec->global_lock) {
 312                 status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk);
 313                 if (ACPI_FAILURE(status)) {
 314                         status = -ENODEV;
 315                         goto unlock;
 316                 }
 317         }
 318         if (!wait_event_timeout(ec->wait, ec_check_ibf0(ec),
 319                                 msecs_to_jiffies(ACPI_EC_DELAY))) {
 320                 pr_err(PREFIX "input buffer is not empty, "
 321                                 "aborting transaction\n");
 322                 status = -ETIME;
 323                 goto end;
 324         }
 325         status = acpi_ec_transaction_unlocked(ec, t, force_poll);
 326 end:
 327         if (ec->global_lock)
 328                 acpi_release_global_lock(glk);
 329 unlock:
 330         mutex_unlock(&ec->lock);
 331         return status;
 332 }
 333
 334 /*
 335  * Note: samsung nv5000 doesn't work with ec burst mode.
 336  * http://bugzilla.kernel.org/show_bug.cgi?id=4980
 337  */
 338 int acpi_ec_burst_enable(struct acpi_ec *ec)
 339 {
 340         u8 d;
 341         struct transaction t = {.command = ACPI_EC_BURST_ENABLE,
 342                                 .wdata = NULL, .rdata = &d,
 343                                 .wlen = 0, .rlen = 1};
 344
 345         return acpi_ec_transaction(ec, &t, 0);
 346 }
 347
 348 int acpi_ec_burst_disable(struct acpi_ec *ec)
 349 {
 350         struct transaction t = {.command = ACPI_EC_BURST_DISABLE,
 351                                 .wdata = NULL, .rdata = NULL,
 352                                 .wlen = 0, .rlen = 0};
 353
 354         return (acpi_ec_read_status(ec) & ACPI_EC_FLAG_BURST) ?
 355                                 acpi_ec_transaction(ec, &t, 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         struct transaction t = {.command = ACPI_EC_COMMAND_READ,
 363                                 .wdata = &address, .rdata = &d,
 364                                 .wlen = 1, .rlen = 1};
 365
 366         result = acpi_ec_transaction(ec, &t, 0);
 367         *data = d;
 368         return result;
 369 }
 370
 371 static int acpi_ec_write(struct acpi_ec *ec, u8 address, u8 data)
 372 {
 373         u8 wdata[2] = { address, data };
 374         struct transaction t = {.command = ACPI_EC_COMMAND_WRITE,
 375                                 .wdata = wdata, .rdata = NULL,
 376                                 .wlen = 2, .rlen = 0};
 377
 378         return acpi_ec_transaction(ec, &t, 0);
 379 }
 380
 381 /*
 382  * Externally callable EC access functions. For now, assume 1 EC only
 383  */
 384 int ec_burst_enable(void)
 385 {
 386         if (!first_ec)
 387                 return -ENODEV;
 388         return acpi_ec_burst_enable(first_ec);
 389 }
 390
 391 EXPORT_SYMBOL(ec_burst_enable);
 392
 393 int ec_burst_disable(void)
 394 {
 395         if (!first_ec)
 396                 return -ENODEV;
 397         return acpi_ec_burst_disable(first_ec);
 398 }
 399
 400 EXPORT_SYMBOL(ec_burst_disable);
 401
 402 int ec_read(u8 addr, u8 * val)
 403 {
 404         int err;
 405         u8 temp_data;
 406
 407         if (!first_ec)
 408                 return -ENODEV;
 409
 410         err = acpi_ec_read(first_ec, addr, &temp_data);
 411
 412         if (!err) {
 413                 *val = temp_data;
 414                 return 0;
 415         } else
 416                 return err;
 417 }
 418
 419 EXPORT_SYMBOL(ec_read);
 420
 421 int ec_write(u8 addr, u8 val)
 422 {
 423         int err;
 424
 425         if (!first_ec)
 426                 return -ENODEV;
 427
 428         err = acpi_ec_write(first_ec, addr, val);
 429
 430         return err;
 431 }
 432
 433 EXPORT_SYMBOL(ec_write);
 434
 435 int ec_transaction(u8 command,
 436                    const u8 * wdata, unsigned wdata_len,
 437                    u8 * rdata, unsigned rdata_len,
 438                    int force_poll)
 439 {
 440         struct transaction t = {.command = command,
 441                                 .wdata = wdata, .rdata = rdata,
 442                                 .wlen = wdata_len, .rlen = rdata_len};
 443         if (!first_ec)
 444                 return -ENODEV;
 445
 446         return acpi_ec_transaction(first_ec, &t, force_poll);
 447 }
 448
 449 EXPORT_SYMBOL(ec_transaction);
 450
 451 static int acpi_ec_query(struct acpi_ec *ec, u8 * data)
 452 {
 453         int result;
 454         u8 d;
 455         struct transaction t = {.command = ACPI_EC_COMMAND_QUERY,
 456                                 .wdata = NULL, .rdata = &d,
 457                                 .wlen = 0, .rlen = 1};
 458         if (!ec || !data)
 459                 return -EINVAL;
 460
 461         /*
 462          * Query the EC to find out which _Qxx method we need to evaluate.
 463          * Note that successful completion of the query causes the ACPI_EC_SCI
 464          * bit to be cleared (and thus clearing the interrupt source).
 465          */
 466
 467         result = acpi_ec_transaction(ec, &t, 0);
 468         if (result)
 469                 return result;
 470
 471         if (!d)
 472                 return -ENODATA;
 473
 474         *data = d;
 475         return 0;
 476 }
 477
 478 /* --------------------------------------------------------------------------
 479                                 Event Management
 480    -------------------------------------------------------------------------- */
 481 int acpi_ec_add_query_handler(struct acpi_ec *ec, u8 query_bit,
 482                               acpi_handle handle, acpi_ec_query_func func,
 483                               void *data)
 484 {
 485         struct acpi_ec_query_handler *handler =
 486             kzalloc(sizeof(struct acpi_ec_query_handler), GFP_KERNEL);
 487         if (!handler)
 488                 return -ENOMEM;
 489
 490         handler->query_bit = query_bit;
 491         handler->handle = handle;
 492         handler->func = func;
 493         handler->data = data;
 494         mutex_lock(&ec->lock);
 495         list_add(&handler->node, &ec->list);
 496         mutex_unlock(&ec->lock);
 497         return 0;
 498 }
 499
 500 EXPORT_SYMBOL_GPL(acpi_ec_add_query_handler);
 501
 502 void acpi_ec_remove_query_handler(struct acpi_ec *ec, u8 query_bit)
 503 {
 504         struct acpi_ec_query_handler *handler, *tmp;
 505         mutex_lock(&ec->lock);
 506         list_for_each_entry_safe(handler, tmp, &ec->list, node) {
 507                 if (query_bit == handler->query_bit) {
 508                         list_del(&handler->node);
 509                         kfree(handler);
 510                 }
 511         }
 512         mutex_unlock(&ec->lock);
 513 }
 514
 515 EXPORT_SYMBOL_GPL(acpi_ec_remove_query_handler);
 516
 517 static void acpi_ec_gpe_query(void *ec_cxt)
 518 {
 519         struct acpi_ec *ec = ec_cxt;
 520         u8 value = 0;
 521         struct acpi_ec_query_handler *handler, copy;
 522
 523         if (!ec || acpi_ec_query(ec, &value))
 524                 return;
 525         mutex_lock(&ec->lock);
 526         list_for_each_entry(handler, &ec->list, node) {
 527                 if (value == handler->query_bit) {
 528                         /* have custom handler for this bit */
 529                         memcpy(&copy, handler, sizeof(copy));
 530                         mutex_unlock(&ec->lock);
 531                         if (copy.func) {
 532                                 copy.func(copy.data);
 533                         } else if (copy.handle) {
 534                                 acpi_evaluate_object(copy.handle, NULL, NULL, NULL);
 535                         }
 536                         return;
 537                 }
 538         }
 539         mutex_unlock(&ec->lock);
 540 }
 541
 542 static u32 acpi_ec_gpe_handler(void *data)
 543 {
 544         struct acpi_ec *ec = data;
 545         u8 status;
 546
 547         pr_debug(PREFIX "~~~> interrupt\n");
 548         status = acpi_ec_read_status(ec);
 549
 550         gpe_transaction(ec, status);
 551         if (ec_transaction_done(ec) && (status & ACPI_EC_FLAG_IBF) == 0)
 552                 wake_up(&ec->wait);
 553
 554         ec_check_sci(ec, status);
 555         if (!test_bit(EC_FLAGS_GPE_MODE, &ec->flags) &&
 556             !test_bit(EC_FLAGS_NO_GPE, &ec->flags)) {
 557                 /* this is non-query, must be confirmation */
 558                 if (printk_ratelimit())
 559                         pr_info(PREFIX "non-query interrupt received,"
 560                                 " switching to interrupt mode\n");
 561                 set_bit(EC_FLAGS_GPE_MODE, &ec->flags);
 562         }
 563         return ACPI_INTERRUPT_HANDLED;
 564 }
 565
 566 /* --------------------------------------------------------------------------
 567                              Address Space Management
 568    -------------------------------------------------------------------------- */
 569
 570 static acpi_status
 571 acpi_ec_space_handler(u32 function, acpi_physical_address address,
 572                       u32 bits, acpi_integer *value,
 573                       void *handler_context, void *region_context)
 574 {
 575         struct acpi_ec *ec = handler_context;
 576         int result = 0, i;
 577         u8 temp = 0;
 578
 579         if ((address > 0xFF) || !value || !handler_context)
 580                 return AE_BAD_PARAMETER;
 581
 582         if (function != ACPI_READ && function != ACPI_WRITE)
 583                 return AE_BAD_PARAMETER;
 584
 585         if (bits != 8 && acpi_strict)
 586                 return AE_BAD_PARAMETER;
 587
 588         acpi_ec_burst_enable(ec);
 589
 590         if (function == ACPI_READ) {
 591                 result = acpi_ec_read(ec, address, &temp);
 592                 *value = temp;
 593         } else {
 594                 temp = 0xff & (*value);
 595                 result = acpi_ec_write(ec, address, temp);
 596         }
 597
 598         for (i = 8; unlikely(bits - i > 0); i += 8) {
 599                 ++address;
 600                 if (function == ACPI_READ) {
 601                         result = acpi_ec_read(ec, address, &temp);
 602                         (*value) |= ((acpi_integer)temp) << i;
 603                 } else {
 604                         temp = 0xff & ((*value) >> i);
 605                         result = acpi_ec_write(ec, address, temp);
 606                 }
 607         }
 608
 609         acpi_ec_burst_disable(ec);
 610
 611         switch (result) {
 612         case -EINVAL:
 613                 return AE_BAD_PARAMETER;
 614                 break;
 615         case -ENODEV:
 616                 return AE_NOT_FOUND;
 617                 break;
 618         case -ETIME:
 619                 return AE_TIME;
 620                 break;
 621         default:
 622                 return AE_OK;
 623         }
 624 }
 625
 626 /* --------------------------------------------------------------------------
 627                               FS Interface (/proc)
 628    -------------------------------------------------------------------------- */
 629
 630 static struct proc_dir_entry *acpi_ec_dir;
 631
 632 static int acpi_ec_read_info(struct seq_file *seq, void *offset)
 633 {
 634         struct acpi_ec *ec = seq->private;
 635
 636         if (!ec)
 637                 goto end;
 638
 639         seq_printf(seq, "gpe:\t\t\t0x%02x\n", (u32) ec->gpe);
 640         seq_printf(seq, "ports:\t\t\t0x%02x, 0x%02x\n",
 641                    (unsigned)ec->command_addr, (unsigned)ec->data_addr);
 642         seq_printf(seq, "use global lock:\t%s\n",
 643                    ec->global_lock ? "yes" : "no");
 644       end:
 645         return 0;
 646 }
 647
 648 static int acpi_ec_info_open_fs(struct inode *inode, struct file *file)
 649 {
 650         return single_open(file, acpi_ec_read_info, PDE(inode)->data);
 651 }
 652
 653 static struct file_operations acpi_ec_info_ops = {
 654         .open = acpi_ec_info_open_fs,
 655         .read = seq_read,
 656         .llseek = seq_lseek,
 657         .release = single_release,
 658         .owner = THIS_MODULE,
 659 };
 660
 661 static int acpi_ec_add_fs(struct acpi_device *device)
 662 {
 663         struct proc_dir_entry *entry = NULL;
 664
 665         if (!acpi_device_dir(device)) {
 666                 acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device),
 667                                                      acpi_ec_dir);
 668                 if (!acpi_device_dir(device))
 669                         return -ENODEV;
 670         }
 671
 672         entry = proc_create_data(ACPI_EC_FILE_INFO, S_IRUGO,
 673                                  acpi_device_dir(device),
 674                                  &acpi_ec_info_ops, acpi_driver_data(device));
 675         if (!entry)
 676                 return -ENODEV;
 677         return 0;
 678 }
 679
 680 static int acpi_ec_remove_fs(struct acpi_device *device)
 681 {
 682
 683         if (acpi_device_dir(device)) {
 684                 remove_proc_entry(ACPI_EC_FILE_INFO, acpi_device_dir(device));
 685                 remove_proc_entry(acpi_device_bid(device), acpi_ec_dir);
 686                 acpi_device_dir(device) = NULL;
 687         }
 688
 689         return 0;
 690 }
 691
 692 /* --------------------------------------------------------------------------
 693                                Driver Interface
 694    -------------------------------------------------------------------------- */
 695 static acpi_status
 696 ec_parse_io_ports(struct acpi_resource *resource, void *context);
 697
 698 static struct acpi_ec *make_acpi_ec(void)
 699 {
 700         struct acpi_ec *ec = kzalloc(sizeof(struct acpi_ec), GFP_KERNEL);
 701         if (!ec)
 702                 return NULL;
 703         ec->flags = 1 << EC_FLAGS_QUERY_PENDING;
 704         mutex_init(&ec->lock);
 705         init_waitqueue_head(&ec->wait);
 706         INIT_LIST_HEAD(&ec->list);
 707         spin_lock_init(&ec->curr_lock);
 708         return ec;
 709 }
 710
 711 static acpi_status
 712 acpi_ec_register_query_methods(acpi_handle handle, u32 level,
 713                                void *context, void **return_value)
 714 {
 715         struct acpi_namespace_node *node = handle;
 716         struct acpi_ec *ec = context;
 717         int value = 0;
 718         if (sscanf(node->name.ascii, "_Q%x", &value) == 1) {
 719                 acpi_ec_add_query_handler(ec, value, handle, NULL, NULL);
 720         }
 721         return AE_OK;
 722 }
 723
 724 static acpi_status
 725 ec_parse_device(acpi_handle handle, u32 Level, void *context, void **retval)
 726 {
 727         acpi_status status;
 728
 729         struct acpi_ec *ec = context;
 730         status = acpi_walk_resources(handle, METHOD_NAME__CRS,
 731                                      ec_parse_io_ports, ec);
 732         if (ACPI_FAILURE(status))
 733                 return status;
 734
 735         /* Get GPE bit assignment (EC events). */
 736         /* TODO: Add support for _GPE returning a package */
 737         status = acpi_evaluate_integer(handle, "_GPE", NULL, &ec->gpe);
 738         if (ACPI_FAILURE(status))
 739                 return status;
 740         /* Use the global lock for all EC transactions? */
 741         acpi_evaluate_integer(handle, "_GLK", NULL, &ec->global_lock);
 742         ec->handle = handle;
 743         return AE_CTRL_TERMINATE;
 744 }
 745
 746 static void ec_remove_handlers(struct acpi_ec *ec)
 747 {
 748         if (ACPI_FAILURE(acpi_remove_address_space_handler(ec->handle,
 749                                 ACPI_ADR_SPACE_EC, &acpi_ec_space_handler)))
 750                 pr_err(PREFIX "failed to remove space handler\n");
 751         if (ACPI_FAILURE(acpi_remove_gpe_handler(NULL, ec->gpe,
 752                                 &acpi_ec_gpe_handler)))
 753                 pr_err(PREFIX "failed to remove gpe handler\n");
 754         clear_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags);
 755 }
 756
 757 static int acpi_ec_add(struct acpi_device *device)
 758 {
 759         struct acpi_ec *ec = NULL;
 760
 761         if (!device)
 762                 return -EINVAL;
 763         strcpy(acpi_device_name(device), ACPI_EC_DEVICE_NAME);
 764         strcpy(acpi_device_class(device), ACPI_EC_CLASS);
 765
 766         /* Check for boot EC */
 767         if (boot_ec &&
 768             (boot_ec->handle == device->handle ||
 769              boot_ec->handle == ACPI_ROOT_OBJECT)) {
 770                 ec = boot_ec;
 771                 boot_ec = NULL;
 772         } else {
 773                 ec = make_acpi_ec();
 774                 if (!ec)
 775                         return -ENOMEM;
 776                 if (ec_parse_device(device->handle, 0, ec, NULL) !=
 777                     AE_CTRL_TERMINATE) {
 778                         kfree(ec);
 779                         return -EINVAL;
 780                 }
 781         }
 782
 783         ec->handle = device->handle;
 784
 785         /* Find and register all query methods */
 786         acpi_walk_namespace(ACPI_TYPE_METHOD, ec->handle, 1,
 787                             acpi_ec_register_query_methods, ec, NULL);
 788
 789         if (!first_ec)
 790                 first_ec = ec;
 791         acpi_driver_data(device) = ec;
 792         acpi_ec_add_fs(device);
 793         pr_info(PREFIX "GPE = 0x%lx, I/O: command/status = 0x%lx, data = 0x%lx\n",
 794                           ec->gpe, ec->command_addr, ec->data_addr);
 795         pr_info(PREFIX "driver started in %s mode\n",
 796                 (test_bit(EC_FLAGS_GPE_MODE, &ec->flags))?"interrupt":"poll");
 797         return 0;
 798 }
 799
 800 static int acpi_ec_remove(struct acpi_device *device, int type)
 801 {
 802         struct acpi_ec *ec;
 803         struct acpi_ec_query_handler *handler, *tmp;
 804
 805         if (!device)
 806                 return -EINVAL;
 807
 808         ec = acpi_driver_data(device);
 809         mutex_lock(&ec->lock);
 810         list_for_each_entry_safe(handler, tmp, &ec->list, node) {
 811                 list_del(&handler->node);
 812                 kfree(handler);
 813         }
 814         mutex_unlock(&ec->lock);
 815         acpi_ec_remove_fs(device);
 816         acpi_driver_data(device) = NULL;
 817         if (ec == first_ec)
 818                 first_ec = NULL;
 819         kfree(ec);
 820         return 0;
 821 }
 822
 823 static acpi_status
 824 ec_parse_io_ports(struct acpi_resource *resource, void *context)
 825 {
 826         struct acpi_ec *ec = context;
 827
 828         if (resource->type != ACPI_RESOURCE_TYPE_IO)
 829                 return AE_OK;
 830
 831         /*
 832          * The first address region returned is the data port, and
 833          * the second address region returned is the status/command
 834          * port.
 835          */
 836         if (ec->data_addr == 0)
 837                 ec->data_addr = resource->data.io.minimum;
 838         else if (ec->command_addr == 0)
 839                 ec->command_addr = resource->data.io.minimum;
 840         else
 841                 return AE_CTRL_TERMINATE;
 842
 843         return AE_OK;
 844 }
 845
 846 static int ec_install_handlers(struct acpi_ec *ec)
 847 {
 848         acpi_status status;
 849         if (test_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags))
 850                 return 0;
 851         status = acpi_install_gpe_handler(NULL, ec->gpe,
 852                                   ACPI_GPE_EDGE_TRIGGERED,
 853                                   &acpi_ec_gpe_handler, ec);
 854         if (ACPI_FAILURE(status))
 855                 return -ENODEV;
 856         acpi_set_gpe_type(NULL, ec->gpe, ACPI_GPE_TYPE_RUNTIME);
 857         acpi_enable_gpe(NULL, ec->gpe, ACPI_NOT_ISR);
 858         status = acpi_install_address_space_handler(ec->handle,
 859                                                     ACPI_ADR_SPACE_EC,
 860                                                     &acpi_ec_space_handler,
 861                                                     NULL, ec);
 862         if (ACPI_FAILURE(status)) {
 863                 acpi_remove_gpe_handler(NULL, ec->gpe, &acpi_ec_gpe_handler);
 864                 return -ENODEV;
 865         }
 866
 867         set_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags);
 868         return 0;
 869 }
 870
 871 static int acpi_ec_start(struct acpi_device *device)
 872 {
 873         struct acpi_ec *ec;
 874         int ret = 0;
 875
 876         if (!device)
 877                 return -EINVAL;
 878
 879         ec = acpi_driver_data(device);
 880
 881         if (!ec)
 882                 return -EINVAL;
 883
 884         ret = ec_install_handlers(ec);
 885
 886         /* EC is fully operational, allow queries */
 887         clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags);
 888         return ret;
 889 }
 890
 891 static int acpi_ec_stop(struct acpi_device *device, int type)
 892 {
 893         struct acpi_ec *ec;
 894         if (!device)
 895                 return -EINVAL;
 896         ec = acpi_driver_data(device);
 897         if (!ec)
 898                 return -EINVAL;
 899         ec_remove_handlers(ec);
 900
 901         return 0;
 902 }
 903
 904 int __init acpi_boot_ec_enable(void)
 905 {
 906         if (!boot_ec || test_bit(EC_FLAGS_HANDLERS_INSTALLED, &boot_ec->flags))
 907                 return 0;
 908         if (!ec_install_handlers(boot_ec)) {
 909                 first_ec = boot_ec;
 910                 return 0;
 911         }
 912         return -EFAULT;
 913 }
 914
 915 static const struct acpi_device_id ec_device_ids[] = {
 916         {"PNP0C09", 0},
 917         {"", 0},
 918 };
 919
 920 int __init acpi_ec_ecdt_probe(void)
 921 {
 922         int ret;
 923         acpi_status status;
 924         struct acpi_table_ecdt *ecdt_ptr;
 925
 926         boot_ec = make_acpi_ec();
 927         if (!boot_ec)
 928                 return -ENOMEM;
 929         /*
 930          * Generate a boot ec context
 931          */
 932         status = acpi_get_table(ACPI_SIG_ECDT, 1,
 933                                 (struct acpi_table_header **)&ecdt_ptr);
 934         if (ACPI_SUCCESS(status)) {
 935                 pr_info(PREFIX "EC description table is found, configuring boot EC\n");
 936                 boot_ec->command_addr = ecdt_ptr->control.address;
 937                 boot_ec->data_addr = ecdt_ptr->data.address;
 938                 if (dmi_check_system(ec_dmi_table)) {
 939                         /*
 940                          * If the board falls into ec_dmi_table, it means
 941                          * that ECDT table gives the incorrect command/status
 942                          * & data I/O address. Just fix it.
 943                          */
 944                         boot_ec->data_addr = ecdt_ptr->control.address;
 945                         boot_ec->command_addr = ecdt_ptr->data.address;
 946                 }
 947                 boot_ec->gpe = ecdt_ptr->gpe;
 948                 boot_ec->handle = ACPI_ROOT_OBJECT;
 949                 acpi_get_handle(ACPI_ROOT_OBJECT, ecdt_ptr->id, &boot_ec->handle);
 950         } else {
 951                 /* This workaround is needed only on some broken machines,
 952                  * which require early EC, but fail to provide ECDT */
 953                 acpi_handle x;
 954                 printk(KERN_DEBUG PREFIX "Look up EC in DSDT\n");
 955                 status = acpi_get_devices(ec_device_ids[0].id, ec_parse_device,
 956                                                 boot_ec, NULL);
 957                 /* Check that acpi_get_devices actually find something */
 958                 if (ACPI_FAILURE(status) || !boot_ec->handle)
 959                         goto error;
 960                 /* We really need to limit this workaround, the only ASUS,
 961                  * which needs it, has fake EC._INI method, so use it as flag.
 962                  * Keep boot_ec struct as it will be needed soon.
 963                  */
 964                 if (ACPI_FAILURE(acpi_get_handle(boot_ec->handle, "_INI", &x)))
 965                         return -ENODEV;
 966         }
 967
 968         ret = ec_install_handlers(boot_ec);
 969         if (!ret) {
 970                 first_ec = boot_ec;
 971                 return 0;
 972         }
 973       error:
 974         kfree(boot_ec);
 975         boot_ec = NULL;
 976         return -ENODEV;
 977 }
 978
 979 static int acpi_ec_suspend(struct acpi_device *device, pm_message_t state)
 980 {
 981         struct acpi_ec *ec = acpi_driver_data(device);
 982         /* Stop using GPE */
 983         set_bit(EC_FLAGS_NO_GPE, &ec->flags);
 984         clear_bit(EC_FLAGS_GPE_MODE, &ec->flags);
 985         acpi_disable_gpe(NULL, ec->gpe, ACPI_NOT_ISR);
 986         return 0;
 987 }
 988
 989 static int acpi_ec_resume(struct acpi_device *device)
 990 {
 991         struct acpi_ec *ec = acpi_driver_data(device);
 992         /* Enable use of GPE back */
 993         clear_bit(EC_FLAGS_NO_GPE, &ec->flags);
 994         acpi_enable_gpe(NULL, ec->gpe, ACPI_NOT_ISR);
 995         return 0;
 996 }
 997
 998 static struct acpi_driver acpi_ec_driver = {
 999         .name = "ec",
1000         .class = ACPI_EC_CLASS,
1001         .ids = ec_device_ids,
1002         .ops = {
1003                 .add = acpi_ec_add,
1004                 .remove = acpi_ec_remove,
1005                 .start = acpi_ec_start,
1006                 .stop = acpi_ec_stop,
1007                 .suspend = acpi_ec_suspend,
1008                 .resume = acpi_ec_resume,
1009                 },
1010 };
1011
1012 static int __init acpi_ec_init(void)
1013 {
1014         int result = 0;
1015
1016         if (acpi_disabled)
1017                 return 0;
1018
1019         acpi_ec_dir = proc_mkdir(ACPI_EC_CLASS, acpi_root_dir);
1020         if (!acpi_ec_dir)
1021                 return -ENODEV;
1022
1023         /* Now register the driver for the EC */
1024         result = acpi_bus_register_driver(&acpi_ec_driver);
1025         if (result < 0) {
1026                 remove_proc_entry(ACPI_EC_CLASS, acpi_root_dir);
1027                 return -ENODEV;
1028         }
1029
1030         return result;
1031 }
1032
1033 subsys_initcall(acpi_ec_init);
1034
1035 /* EC driver currently not unloadable */
1036 #if 0
1037 static void __exit acpi_ec_exit(void)
1038 {
1039
1040         acpi_bus_unregister_driver(&acpi_ec_driver);
1041
1042         remove_proc_entry(ACPI_EC_CLASS, acpi_root_dir);
1043
1044         return;
1045 }
1046 #endif  /* 0 */