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
  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 */
  60 enum 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_UDELAY          100     /* Wait 100us before polling EC again */
  71
  72 #define ACPI_EC_STORM_THRESHOLD 8       /* number of false interrupts
  73                                            per one transaction */
  74
  75 enum {
  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 */
  87 typedef int (*acpi_ec_query_func) (void *data);
  88
  89 struct 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
  97 struct 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
 109 static 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
 123 /*
 124  * Some Asus system have exchanged ECDT data/command IO addresses.
 125  */
 126 static int print_ecdt_error(const struct dmi_system_id *id)
 127 {
 128         printk(KERN_NOTICE PREFIX "%s detected - "
 129                 "ECDT has exchanged control/data I/O address\n",
 130                 id->ident);
 131         return 0;
 132 }
 133
 134 static struct dmi_system_id __cpuinitdata ec_dmi_table[] = {
 135         {
 136         print_ecdt_error, "Asus L4R", {
 137         DMI_MATCH(DMI_BIOS_VERSION, "1008.006"),
 138         DMI_MATCH(DMI_PRODUCT_NAME, "L4R"),
 139         DMI_MATCH(DMI_BOARD_NAME, "L4R") }, NULL},
 140         {
 141         print_ecdt_error, "Asus M6R", {
 142         DMI_MATCH(DMI_BIOS_VERSION, "0207"),
 143         DMI_MATCH(DMI_PRODUCT_NAME, "M6R"),
 144         DMI_MATCH(DMI_BOARD_NAME, "M6R") }, NULL},
 145         {},
 146 };
 147
 148 /* --------------------------------------------------------------------------
 149                              Transaction Management
 150    -------------------------------------------------------------------------- */
 151
 152 static inline u8 acpi_ec_read_status(struct acpi_ec *ec)
 153 {
 154         u8 x = inb(ec->command_addr);
 155         pr_debug(PREFIX "---> status = 0x%2.2x\n", x);
 156         return x;
 157 }
 158
 159 static inline u8 acpi_ec_read_data(struct acpi_ec *ec)
 160 {
 161         u8 x = inb(ec->data_addr);
 162         pr_debug(PREFIX "---> data = 0x%2.2x\n", x);
 163         return x;
 164 }
 165
 166 static inline void acpi_ec_write_cmd(struct acpi_ec *ec, u8 command)
 167 {
 168         pr_debug(PREFIX "<--- command = 0x%2.2x\n", command);
 169         outb(command, ec->command_addr);
 170 }
 171
 172 static inline void acpi_ec_write_data(struct acpi_ec *ec, u8 data)
 173 {
 174         pr_debug(PREFIX "<--- data = 0x%2.2x\n", data);
 175         outb(data, ec->data_addr);
 176 }
 177
 178 static int ec_transaction_done(struct acpi_ec *ec)
 179 {
 180         unsigned long flags;
 181         int ret = 0;
 182         spin_lock_irqsave(&ec->curr_lock, flags);
 183         if (!ec->curr || ec->curr->done)
 184                 ret = 1;
 185         spin_unlock_irqrestore(&ec->curr_lock, flags);
 186         return ret;
 187 }
 188
 189 static void start_transaction(struct acpi_ec *ec)
 190 {
 191         ec->curr->irq_count = ec->curr->wi = ec->curr->ri = 0;
 192         ec->curr->done = false;
 193         acpi_ec_write_cmd(ec, ec->curr->command);
 194 }
 195
 196 static void gpe_transaction(struct acpi_ec *ec, u8 status)
 197 {
 198         unsigned long flags;
 199         spin_lock_irqsave(&ec->curr_lock, flags);
 200         if (!ec->curr)
 201                 goto unlock;
 202         if (ec->curr->wlen > ec->curr->wi) {
 203                 if ((status & ACPI_EC_FLAG_IBF) == 0)
 204                         acpi_ec_write_data(ec,
 205                                 ec->curr->wdata[ec->curr->wi++]);
 206                 else
 207                         goto err;
 208         } else if (ec->curr->rlen > ec->curr->ri) {
 209                 if ((status & ACPI_EC_FLAG_OBF) == 1) {
 210                         ec->curr->rdata[ec->curr->ri++] = acpi_ec_read_data(ec);
 211                         if (ec->curr->rlen == ec->curr->ri)
 212                                 ec->curr->done = true;
 213                 } else
 214                         goto err;
 215         } else if (ec->curr->wlen == ec->curr->wi &&
 216                    (status & ACPI_EC_FLAG_IBF) == 0)
 217                 ec->curr->done = true;
 218         goto unlock;
 219 err:
 220         /* false interrupt, state didn't change */
 221         if (in_interrupt())
 222                 ++ec->curr->irq_count;
 223 unlock:
 224         spin_unlock_irqrestore(&ec->curr_lock, flags);
 225 }
 226
 227 static int acpi_ec_wait(struct acpi_ec *ec)
 228 {
 229         if (wait_event_timeout(ec->wait, ec_transaction_done(ec),
 230                                msecs_to_jiffies(ACPI_EC_DELAY)))
 231                 return 0;
 232         /* try restart command if we get any false interrupts */
 233         if (ec->curr->irq_count &&
 234             (acpi_ec_read_status(ec) & ACPI_EC_FLAG_IBF) == 0) {
 235                 pr_debug(PREFIX "controller reset, restart transaction\n");
 236                 start_transaction(ec);
 237                 if (wait_event_timeout(ec->wait, ec_transaction_done(ec),
 238                                         msecs_to_jiffies(ACPI_EC_DELAY)))
 239                         return 0;
 240         }
 241         /* missing GPEs, switch back to poll mode */
 242         if (printk_ratelimit())
 243                 pr_info(PREFIX "missing confirmations, "
 244                                 "switch off interrupt mode.\n");
 245         set_bit(EC_FLAGS_NO_GPE, &ec->flags);
 246         clear_bit(EC_FLAGS_GPE_MODE, &ec->flags);
 247         return 1;
 248 }
 249
 250 static void acpi_ec_gpe_query(void *ec_cxt);
 251
 252 static int ec_check_sci(struct acpi_ec *ec, u8 state)
 253 {
 254         if (state & ACPI_EC_FLAG_SCI) {
 255                 if (!test_and_set_bit(EC_FLAGS_QUERY_PENDING, &ec->flags))
 256                         return acpi_os_execute(OSL_EC_BURST_HANDLER,
 257                                 acpi_ec_gpe_query, ec);
 258         }
 259         return 0;
 260 }
 261
 262 static int ec_poll(struct acpi_ec *ec)
 263 {
 264         unsigned long delay = jiffies + msecs_to_jiffies(ACPI_EC_DELAY);
 265         udelay(ACPI_EC_UDELAY);
 266         while (time_before(jiffies, delay)) {
 267                 gpe_transaction(ec, acpi_ec_read_status(ec));
 268                 udelay(ACPI_EC_UDELAY);
 269                 if (ec_transaction_done(ec))
 270                         return 0;
 271         }
 272         return -ETIME;
 273 }
 274
 275 static int acpi_ec_transaction_unlocked(struct acpi_ec *ec,
 276                                         struct transaction *t,
 277                                         int force_poll)
 278 {
 279         unsigned long tmp;
 280         int ret = 0;
 281         pr_debug(PREFIX "transaction start\n");
 282         /* disable GPE during transaction if storm is detected */
 283         if (test_bit(EC_FLAGS_GPE_STORM, &ec->flags)) {
 284                 clear_bit(EC_FLAGS_GPE_MODE, &ec->flags);
 285                 acpi_disable_gpe(NULL, ec->gpe);
 286         }
 287         /* start transaction */
 288         spin_lock_irqsave(&ec->curr_lock, tmp);
 289         /* following two actions should be kept atomic */
 290         ec->curr = t;
 291         start_transaction(ec);
 292         if (ec->curr->command == ACPI_EC_COMMAND_QUERY)
 293                 clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags);
 294         spin_unlock_irqrestore(&ec->curr_lock, tmp);
 295         /* if we selected poll mode or failed in GPE-mode do a poll loop */
 296         if (force_poll ||
 297             !test_bit(EC_FLAGS_GPE_MODE, &ec->flags) ||
 298             acpi_ec_wait(ec))
 299                 ret = ec_poll(ec);
 300         pr_debug(PREFIX "transaction end\n");
 301         spin_lock_irqsave(&ec->curr_lock, tmp);
 302         ec->curr = NULL;
 303         spin_unlock_irqrestore(&ec->curr_lock, tmp);
 304         if (test_bit(EC_FLAGS_GPE_STORM, &ec->flags)) {
 305                 /* check if we received SCI during transaction */
 306                 ec_check_sci(ec, acpi_ec_read_status(ec));
 307                 /* it is safe to enable GPE outside of transaction */
 308                 acpi_enable_gpe(NULL, ec->gpe);
 309         } else if (test_bit(EC_FLAGS_GPE_MODE, &ec->flags) &&
 310                    t->irq_count > ACPI_EC_STORM_THRESHOLD) {
 311                 pr_info(PREFIX "GPE storm detected, "
 312                         "transactions will use polling mode\n");
 313                 set_bit(EC_FLAGS_GPE_STORM, &ec->flags);
 314         }
 315         return ret;
 316 }
 317
 318 static int ec_check_ibf0(struct acpi_ec *ec)
 319 {
 320         u8 status = acpi_ec_read_status(ec);
 321         return (status & ACPI_EC_FLAG_IBF) == 0;
 322 }
 323
 324 static int ec_wait_ibf0(struct acpi_ec *ec)
 325 {
 326         unsigned long delay = jiffies + msecs_to_jiffies(ACPI_EC_DELAY);
 327         /* interrupt wait manually if GPE mode is not active */
 328         unsigned long timeout = test_bit(EC_FLAGS_GPE_MODE, &ec->flags) ?
 329                 msecs_to_jiffies(ACPI_EC_DELAY) : msecs_to_jiffies(1);
 330         while (time_before(jiffies, delay))
 331                 if (wait_event_timeout(ec->wait, ec_check_ibf0(ec), timeout))
 332                         return 0;
 333         return -ETIME;
 334 }
 335
 336 static int acpi_ec_transaction(struct acpi_ec *ec, struct transaction *t,
 337                                int force_poll)
 338 {
 339         int status;
 340         u32 glk;
 341         if (!ec || (!t) || (t->wlen && !t->wdata) || (t->rlen && !t->rdata))
 342                 return -EINVAL;
 343         if (t->rdata)
 344                 memset(t->rdata, 0, t->rlen);
 345         mutex_lock(&ec->lock);
 346         if (ec->global_lock) {
 347                 status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk);
 348                 if (ACPI_FAILURE(status)) {
 349                         status = -ENODEV;
 350                         goto unlock;
 351                 }
 352         }
 353         if (ec_wait_ibf0(ec)) {
 354                 pr_err(PREFIX "input buffer is not empty, "
 355                                 "aborting transaction\n");
 356                 status = -ETIME;
 357                 goto end;
 358         }
 359         status = acpi_ec_transaction_unlocked(ec, t, force_poll);
 360 end:
 361         if (ec->global_lock)
 362                 acpi_release_global_lock(glk);
 363 unlock:
 364         mutex_unlock(&ec->lock);
 365         return status;
 366 }
 367
 368 /*
 369  * Note: samsung nv5000 doesn't work with ec burst mode.
 370  * http://bugzilla.kernel.org/show_bug.cgi?id=4980
 371  */
 372 static int acpi_ec_burst_enable(struct acpi_ec *ec)
 373 {
 374         u8 d;
 375         struct transaction t = {.command = ACPI_EC_BURST_ENABLE,
 376                                 .wdata = NULL, .rdata = &d,
 377                                 .wlen = 0, .rlen = 1};
 378
 379         return acpi_ec_transaction(ec, &t, 0);
 380 }
 381
 382 static int acpi_ec_burst_disable(struct acpi_ec *ec)
 383 {
 384         struct transaction t = {.command = ACPI_EC_BURST_DISABLE,
 385                                 .wdata = NULL, .rdata = NULL,
 386                                 .wlen = 0, .rlen = 0};
 387
 388         return (acpi_ec_read_status(ec) & ACPI_EC_FLAG_BURST) ?
 389                                 acpi_ec_transaction(ec, &t, 0) : 0;
 390 }
 391
 392 static int acpi_ec_read(struct acpi_ec *ec, u8 address, u8 * data)
 393 {
 394         int result;
 395         u8 d;
 396         struct transaction t = {.command = ACPI_EC_COMMAND_READ,
 397                                 .wdata = &address, .rdata = &d,
 398                                 .wlen = 1, .rlen = 1};
 399
 400         result = acpi_ec_transaction(ec, &t, 0);
 401         *data = d;
 402         return result;
 403 }
 404
 405 static int acpi_ec_write(struct acpi_ec *ec, u8 address, u8 data)
 406 {
 407         u8 wdata[2] = { address, data };
 408         struct transaction t = {.command = ACPI_EC_COMMAND_WRITE,
 409                                 .wdata = wdata, .rdata = NULL,
 410                                 .wlen = 2, .rlen = 0};
 411
 412         return acpi_ec_transaction(ec, &t, 0);
 413 }
 414
 415 /*
 416  * Externally callable EC access functions. For now, assume 1 EC only
 417  */
 418 int ec_burst_enable(void)
 419 {
 420         if (!first_ec)
 421                 return -ENODEV;
 422         return acpi_ec_burst_enable(first_ec);
 423 }
 424
 425 EXPORT_SYMBOL(ec_burst_enable);
 426
 427 int ec_burst_disable(void)
 428 {
 429         if (!first_ec)
 430                 return -ENODEV;
 431         return acpi_ec_burst_disable(first_ec);
 432 }
 433
 434 EXPORT_SYMBOL(ec_burst_disable);
 435
 436 int ec_read(u8 addr, u8 * val)
 437 {
 438         int err;
 439         u8 temp_data;
 440
 441         if (!first_ec)
 442                 return -ENODEV;
 443
 444         err = acpi_ec_read(first_ec, addr, &temp_data);
 445
 446         if (!err) {
 447                 *val = temp_data;
 448                 return 0;
 449         } else
 450                 return err;
 451 }
 452
 453 EXPORT_SYMBOL(ec_read);
 454
 455 int ec_write(u8 addr, u8 val)
 456 {
 457         int err;
 458
 459         if (!first_ec)
 460                 return -ENODEV;
 461
 462         err = acpi_ec_write(first_ec, addr, val);
 463
 464         return err;
 465 }
 466
 467 EXPORT_SYMBOL(ec_write);
 468
 469 int ec_transaction(u8 command,
 470                    const u8 * wdata, unsigned wdata_len,
 471                    u8 * rdata, unsigned rdata_len,
 472                    int force_poll)
 473 {
 474         struct transaction t = {.command = command,
 475                                 .wdata = wdata, .rdata = rdata,
 476                                 .wlen = wdata_len, .rlen = rdata_len};
 477         if (!first_ec)
 478                 return -ENODEV;
 479
 480         return acpi_ec_transaction(first_ec, &t, force_poll);
 481 }
 482
 483 EXPORT_SYMBOL(ec_transaction);
 484
 485 static int acpi_ec_query(struct acpi_ec *ec, u8 * data)
 486 {
 487         int result;
 488         u8 d;
 489         struct transaction t = {.command = ACPI_EC_COMMAND_QUERY,
 490                                 .wdata = NULL, .rdata = &d,
 491                                 .wlen = 0, .rlen = 1};
 492         if (!ec || !data)
 493                 return -EINVAL;
 494
 495         /*
 496          * Query the EC to find out which _Qxx method we need to evaluate.
 497          * Note that successful completion of the query causes the ACPI_EC_SCI
 498          * bit to be cleared (and thus clearing the interrupt source).
 499          */
 500
 501         result = acpi_ec_transaction(ec, &t, 0);
 502         if (result)
 503                 return result;
 504
 505         if (!d)
 506                 return -ENODATA;
 507
 508         *data = d;
 509         return 0;
 510 }
 511
 512 /* --------------------------------------------------------------------------
 513                                 Event Management
 514    -------------------------------------------------------------------------- */
 515 int acpi_ec_add_query_handler(struct acpi_ec *ec, u8 query_bit,
 516                               acpi_handle handle, acpi_ec_query_func func,
 517                               void *data)
 518 {
 519         struct acpi_ec_query_handler *handler =
 520             kzalloc(sizeof(struct acpi_ec_query_handler), GFP_KERNEL);
 521         if (!handler)
 522                 return -ENOMEM;
 523
 524         handler->query_bit = query_bit;
 525         handler->handle = handle;
 526         handler->func = func;
 527         handler->data = data;
 528         mutex_lock(&ec->lock);
 529         list_add(&handler->node, &ec->list);
 530         mutex_unlock(&ec->lock);
 531         return 0;
 532 }
 533
 534 EXPORT_SYMBOL_GPL(acpi_ec_add_query_handler);
 535
 536 void acpi_ec_remove_query_handler(struct acpi_ec *ec, u8 query_bit)
 537 {
 538         struct acpi_ec_query_handler *handler, *tmp;
 539         mutex_lock(&ec->lock);
 540         list_for_each_entry_safe(handler, tmp, &ec->list, node) {
 541                 if (query_bit == handler->query_bit) {
 542                         list_del(&handler->node);
 543                         kfree(handler);
 544                 }
 545         }
 546         mutex_unlock(&ec->lock);
 547 }
 548
 549 EXPORT_SYMBOL_GPL(acpi_ec_remove_query_handler);
 550
 551 static void acpi_ec_gpe_query(void *ec_cxt)
 552 {
 553         struct acpi_ec *ec = ec_cxt;
 554         u8 value = 0;
 555         struct acpi_ec_query_handler *handler, copy;
 556
 557         if (!ec || acpi_ec_query(ec, &value))
 558                 return;
 559         mutex_lock(&ec->lock);
 560         list_for_each_entry(handler, &ec->list, node) {
 561                 if (value == handler->query_bit) {
 562                         /* have custom handler for this bit */
 563                         memcpy(&copy, handler, sizeof(copy));
 564                         mutex_unlock(&ec->lock);
 565                         if (copy.func) {
 566                                 copy.func(copy.data);
 567                         } else if (copy.handle) {
 568                                 acpi_evaluate_object(copy.handle, NULL, NULL, NULL);
 569                         }
 570                         return;
 571                 }
 572         }
 573         mutex_unlock(&ec->lock);
 574 }
 575
 576 static u32 acpi_ec_gpe_handler(void *data)
 577 {
 578         struct acpi_ec *ec = data;
 579         u8 status;
 580
 581         pr_debug(PREFIX "~~~> interrupt\n");
 582         status = acpi_ec_read_status(ec);
 583
 584         if (test_bit(EC_FLAGS_GPE_MODE, &ec->flags)) {
 585                 gpe_transaction(ec, status);
 586                 if (ec_transaction_done(ec) &&
 587                     (status & ACPI_EC_FLAG_IBF) == 0)
 588                         wake_up(&ec->wait);
 589         }
 590
 591         ec_check_sci(ec, status);
 592         if (!test_bit(EC_FLAGS_GPE_MODE, &ec->flags) &&
 593             !test_bit(EC_FLAGS_NO_GPE, &ec->flags)) {
 594                 /* this is non-query, must be confirmation */
 595                 if (!test_bit(EC_FLAGS_GPE_STORM, &ec->flags)) {
 596                         if (printk_ratelimit())
 597                                 pr_info(PREFIX "non-query interrupt received,"
 598                                         " switching to interrupt mode\n");
 599                 } else {
 600                         /* hush, STORM switches the mode every transaction */
 601                         pr_debug(PREFIX "non-query interrupt received,"
 602                                 " switching to interrupt mode\n");
 603                 }
 604                 set_bit(EC_FLAGS_GPE_MODE, &ec->flags);
 605         }
 606         return ACPI_INTERRUPT_HANDLED;
 607 }
 608
 609 /* --------------------------------------------------------------------------
 610                              Address Space Management
 611    -------------------------------------------------------------------------- */
 612
 613 static acpi_status
 614 acpi_ec_space_handler(u32 function, acpi_physical_address address,
 615                       u32 bits, acpi_integer *value,
 616                       void *handler_context, void *region_context)
 617 {
 618         struct acpi_ec *ec = handler_context;
 619         int result = 0, i;
 620         u8 temp = 0;
 621
 622         if ((address > 0xFF) || !value || !handler_context)
 623                 return AE_BAD_PARAMETER;
 624
 625         if (function != ACPI_READ && function != ACPI_WRITE)
 626                 return AE_BAD_PARAMETER;
 627
 628         if (bits != 8 && acpi_strict)
 629                 return AE_BAD_PARAMETER;
 630
 631         acpi_ec_burst_enable(ec);
 632
 633         if (function == ACPI_READ) {
 634                 result = acpi_ec_read(ec, address, &temp);
 635                 *value = temp;
 636         } else {
 637                 temp = 0xff & (*value);
 638                 result = acpi_ec_write(ec, address, temp);
 639         }
 640
 641         for (i = 8; unlikely(bits - i > 0); i += 8) {
 642                 ++address;
 643                 if (function == ACPI_READ) {
 644                         result = acpi_ec_read(ec, address, &temp);
 645                         (*value) |= ((acpi_integer)temp) << i;
 646                 } else {
 647                         temp = 0xff & ((*value) >> i);
 648                         result = acpi_ec_write(ec, address, temp);
 649                 }
 650         }
 651
 652         acpi_ec_burst_disable(ec);
 653
 654         switch (result) {
 655         case -EINVAL:
 656                 return AE_BAD_PARAMETER;
 657                 break;
 658         case -ENODEV:
 659                 return AE_NOT_FOUND;
 660                 break;
 661         case -ETIME:
 662                 return AE_TIME;
 663                 break;
 664         default:
 665                 return AE_OK;
 666         }
 667 }
 668
 669 /* --------------------------------------------------------------------------
 670                               FS Interface (/proc)
 671    -------------------------------------------------------------------------- */
 672
 673 static struct proc_dir_entry *acpi_ec_dir;
 674
 675 static int acpi_ec_read_info(struct seq_file *seq, void *offset)
 676 {
 677         struct acpi_ec *ec = seq->private;
 678
 679         if (!ec)
 680                 goto end;
 681
 682         seq_printf(seq, "gpe:\t\t\t0x%02x\n", (u32) ec->gpe);
 683         seq_printf(seq, "ports:\t\t\t0x%02x, 0x%02x\n",
 684                    (unsigned)ec->command_addr, (unsigned)ec->data_addr);
 685         seq_printf(seq, "use global lock:\t%s\n",
 686                    ec->global_lock ? "yes" : "no");
 687       end:
 688         return 0;
 689 }
 690
 691 static int acpi_ec_info_open_fs(struct inode *inode, struct file *file)
 692 {
 693         return single_open(file, acpi_ec_read_info, PDE(inode)->data);
 694 }
 695
 696 static struct file_operations acpi_ec_info_ops = {
 697         .open = acpi_ec_info_open_fs,
 698         .read = seq_read,
 699         .llseek = seq_lseek,
 700         .release = single_release,
 701         .owner = THIS_MODULE,
 702 };
 703
 704 static int acpi_ec_add_fs(struct acpi_device *device)
 705 {
 706         struct proc_dir_entry *entry = NULL;
 707
 708         if (!acpi_device_dir(device)) {
 709                 acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device),
 710                                                      acpi_ec_dir);
 711                 if (!acpi_device_dir(device))
 712                         return -ENODEV;
 713         }
 714
 715         entry = proc_create_data(ACPI_EC_FILE_INFO, S_IRUGO,
 716                                  acpi_device_dir(device),
 717                                  &acpi_ec_info_ops, acpi_driver_data(device));
 718         if (!entry)
 719                 return -ENODEV;
 720         return 0;
 721 }
 722
 723 static int acpi_ec_remove_fs(struct acpi_device *device)
 724 {
 725
 726         if (acpi_device_dir(device)) {
 727                 remove_proc_entry(ACPI_EC_FILE_INFO, acpi_device_dir(device));
 728                 remove_proc_entry(acpi_device_bid(device), acpi_ec_dir);
 729                 acpi_device_dir(device) = NULL;
 730         }
 731
 732         return 0;
 733 }
 734
 735 /* --------------------------------------------------------------------------
 736                                Driver Interface
 737    -------------------------------------------------------------------------- */
 738 static acpi_status
 739 ec_parse_io_ports(struct acpi_resource *resource, void *context);
 740
 741 static struct acpi_ec *make_acpi_ec(void)
 742 {
 743         struct acpi_ec *ec = kzalloc(sizeof(struct acpi_ec), GFP_KERNEL);
 744         if (!ec)
 745                 return NULL;
 746         ec->flags = 1 << EC_FLAGS_QUERY_PENDING;
 747         mutex_init(&ec->lock);
 748         init_waitqueue_head(&ec->wait);
 749         INIT_LIST_HEAD(&ec->list);
 750         spin_lock_init(&ec->curr_lock);
 751         return ec;
 752 }
 753
 754 static acpi_status
 755 acpi_ec_register_query_methods(acpi_handle handle, u32 level,
 756                                void *context, void **return_value)
 757 {
 758         char node_name[5];
 759         struct acpi_buffer buffer = { sizeof(node_name), node_name };
 760         struct acpi_ec *ec = context;
 761         int value = 0;
 762         acpi_status status;
 763
 764         status = acpi_get_name(handle, ACPI_SINGLE_NAME, &buffer);
 765
 766         if (ACPI_SUCCESS(status) && sscanf(node_name, "_Q%x", &value) == 1) {
 767                 acpi_ec_add_query_handler(ec, value, handle, NULL, NULL);
 768         }
 769         return AE_OK;
 770 }
 771
 772 static acpi_status
 773 ec_parse_device(acpi_handle handle, u32 Level, void *context, void **retval)
 774 {
 775         acpi_status status;
 776         unsigned long long tmp = 0;
 777
 778         struct acpi_ec *ec = context;
 779         status = acpi_walk_resources(handle, METHOD_NAME__CRS,
 780                                      ec_parse_io_ports, ec);
 781         if (ACPI_FAILURE(status))
 782                 return status;
 783
 784         /* Get GPE bit assignment (EC events). */
 785         /* TODO: Add support for _GPE returning a package */
 786         status = acpi_evaluate_integer(handle, "_GPE", NULL, &tmp);
 787         if (ACPI_FAILURE(status))
 788                 return status;
 789         ec->gpe = tmp;
 790         /* Use the global lock for all EC transactions? */
 791         tmp = 0;
 792         acpi_evaluate_integer(handle, "_GLK", NULL, &tmp);
 793         ec->global_lock = tmp;
 794         ec->handle = handle;
 795         return AE_CTRL_TERMINATE;
 796 }
 797
 798 static void ec_remove_handlers(struct acpi_ec *ec)
 799 {
 800         if (ACPI_FAILURE(acpi_remove_address_space_handler(ec->handle,
 801                                 ACPI_ADR_SPACE_EC, &acpi_ec_space_handler)))
 802                 pr_err(PREFIX "failed to remove space handler\n");
 803         if (ACPI_FAILURE(acpi_remove_gpe_handler(NULL, ec->gpe,
 804                                 &acpi_ec_gpe_handler)))
 805                 pr_err(PREFIX "failed to remove gpe handler\n");
 806         clear_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags);
 807 }
 808
 809 static int acpi_ec_add(struct acpi_device *device)
 810 {
 811         struct acpi_ec *ec = NULL;
 812
 813         if (!device)
 814                 return -EINVAL;
 815         strcpy(acpi_device_name(device), ACPI_EC_DEVICE_NAME);
 816         strcpy(acpi_device_class(device), ACPI_EC_CLASS);
 817
 818         /* Check for boot EC */
 819         if (boot_ec &&
 820             (boot_ec->handle == device->handle ||
 821              boot_ec->handle == ACPI_ROOT_OBJECT)) {
 822                 ec = boot_ec;
 823                 boot_ec = NULL;
 824         } else {
 825                 ec = make_acpi_ec();
 826                 if (!ec)
 827                         return -ENOMEM;
 828                 if (ec_parse_device(device->handle, 0, ec, NULL) !=
 829                     AE_CTRL_TERMINATE) {
 830                         kfree(ec);
 831                         return -EINVAL;
 832                 }
 833         }
 834
 835         ec->handle = device->handle;
 836
 837         /* Find and register all query methods */
 838         acpi_walk_namespace(ACPI_TYPE_METHOD, ec->handle, 1,
 839                             acpi_ec_register_query_methods, ec, NULL);
 840
 841         if (!first_ec)
 842                 first_ec = ec;
 843         device->driver_data = ec;
 844         acpi_ec_add_fs(device);
 845         pr_info(PREFIX "GPE = 0x%lx, I/O: command/status = 0x%lx, data = 0x%lx\n",
 846                           ec->gpe, ec->command_addr, ec->data_addr);
 847         pr_info(PREFIX "driver started in %s mode\n",
 848                 (test_bit(EC_FLAGS_GPE_MODE, &ec->flags))?"interrupt":"poll");
 849         return 0;
 850 }
 851
 852 static int acpi_ec_remove(struct acpi_device *device, int type)
 853 {
 854         struct acpi_ec *ec;
 855         struct acpi_ec_query_handler *handler, *tmp;
 856
 857         if (!device)
 858                 return -EINVAL;
 859
 860         ec = acpi_driver_data(device);
 861         mutex_lock(&ec->lock);
 862         list_for_each_entry_safe(handler, tmp, &ec->list, node) {
 863                 list_del(&handler->node);
 864                 kfree(handler);
 865         }
 866         mutex_unlock(&ec->lock);
 867         acpi_ec_remove_fs(device);
 868         device->driver_data = NULL;
 869         if (ec == first_ec)
 870                 first_ec = NULL;
 871         kfree(ec);
 872         return 0;
 873 }
 874
 875 static acpi_status
 876 ec_parse_io_ports(struct acpi_resource *resource, void *context)
 877 {
 878         struct acpi_ec *ec = context;
 879
 880         if (resource->type != ACPI_RESOURCE_TYPE_IO)
 881                 return AE_OK;
 882
 883         /*
 884          * The first address region returned is the data port, and
 885          * the second address region returned is the status/command
 886          * port.
 887          */
 888         if (ec->data_addr == 0)
 889                 ec->data_addr = resource->data.io.minimum;
 890         else if (ec->command_addr == 0)
 891                 ec->command_addr = resource->data.io.minimum;
 892         else
 893                 return AE_CTRL_TERMINATE;
 894
 895         return AE_OK;
 896 }
 897
 898 static int ec_install_handlers(struct acpi_ec *ec)
 899 {
 900         acpi_status status;
 901         if (test_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags))
 902                 return 0;
 903         status = acpi_install_gpe_handler(NULL, ec->gpe,
 904                                   ACPI_GPE_EDGE_TRIGGERED,
 905                                   &acpi_ec_gpe_handler, ec);
 906         if (ACPI_FAILURE(status))
 907                 return -ENODEV;
 908         acpi_set_gpe_type(NULL, ec->gpe, ACPI_GPE_TYPE_RUNTIME);
 909         acpi_enable_gpe(NULL, ec->gpe);
 910         status = acpi_install_address_space_handler(ec->handle,
 911                                                     ACPI_ADR_SPACE_EC,
 912                                                     &acpi_ec_space_handler,
 913                                                     NULL, ec);
 914         if (ACPI_FAILURE(status)) {
 915                 if (status == AE_NOT_FOUND) {
 916                         /*
 917                          * Maybe OS fails in evaluating the _REG object.
 918                          * The AE_NOT_FOUND error will be ignored and OS
 919                          * continue to initialize EC.
 920                          */
 921                         printk(KERN_ERR "Fail in evaluating the _REG object"
 922                                 " of EC device. Broken bios is suspected.\n");
 923                 } else {
 924                         acpi_remove_gpe_handler(NULL, ec->gpe,
 925                                 &acpi_ec_gpe_handler);
 926                         return -ENODEV;
 927                 }
 928         }
 929
 930         set_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags);
 931         return 0;
 932 }
 933
 934 static int acpi_ec_start(struct acpi_device *device)
 935 {
 936         struct acpi_ec *ec;
 937         int ret = 0;
 938
 939         if (!device)
 940                 return -EINVAL;
 941
 942         ec = acpi_driver_data(device);
 943
 944         if (!ec)
 945                 return -EINVAL;
 946
 947         ret = ec_install_handlers(ec);
 948
 949         /* EC is fully operational, allow queries */
 950         clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags);
 951         return ret;
 952 }
 953
 954 static int acpi_ec_stop(struct acpi_device *device, int type)
 955 {
 956         struct acpi_ec *ec;
 957         if (!device)
 958                 return -EINVAL;
 959         ec = acpi_driver_data(device);
 960         if (!ec)
 961                 return -EINVAL;
 962         ec_remove_handlers(ec);
 963
 964         return 0;
 965 }
 966
 967 int __init acpi_boot_ec_enable(void)
 968 {
 969         if (!boot_ec || test_bit(EC_FLAGS_HANDLERS_INSTALLED, &boot_ec->flags))
 970                 return 0;
 971         if (!ec_install_handlers(boot_ec)) {
 972                 first_ec = boot_ec;
 973                 return 0;
 974         }
 975         return -EFAULT;
 976 }
 977
 978 static const struct acpi_device_id ec_device_ids[] = {
 979         {"PNP0C09", 0},
 980         {"", 0},
 981 };
 982
 983 int __init acpi_ec_ecdt_probe(void)
 984 {
 985         acpi_status status;
 986         struct acpi_table_ecdt *ecdt_ptr;
 987         acpi_handle dummy;
 988
 989         boot_ec = make_acpi_ec();
 990         if (!boot_ec)
 991                 return -ENOMEM;
 992         /*
 993          * Generate a boot ec context
 994          */
 995         status = acpi_get_table(ACPI_SIG_ECDT, 1,
 996                                 (struct acpi_table_header **)&ecdt_ptr);
 997         if (ACPI_SUCCESS(status)) {
 998                 pr_info(PREFIX "EC description table is found, configuring boot EC\n");
 999                 boot_ec->command_addr = ecdt_ptr->control.address;
1000                 boot_ec->data_addr = ecdt_ptr->data.address;
1001                 if (dmi_check_system(ec_dmi_table)) {
1002                         /*
1003                          * If the board falls into ec_dmi_table, it means
1004                          * that ECDT table gives the incorrect command/status
1005                          * & data I/O address. Just fix it.
1006                          */
1007                         boot_ec->data_addr = ecdt_ptr->control.address;
1008                         boot_ec->command_addr = ecdt_ptr->data.address;
1009                 }
1010                 boot_ec->gpe = ecdt_ptr->gpe;
1011                 boot_ec->handle = ACPI_ROOT_OBJECT;
1012                 acpi_get_handle(ACPI_ROOT_OBJECT, ecdt_ptr->id, &boot_ec->handle);
1013                 /* Add some basic check against completely broken table */
1014                 if (boot_ec->data_addr != boot_ec->command_addr)
1015                         goto install;
1016         /* fall through */
1017         }
1018         /* This workaround is needed only on some broken machines,
1019          * which require early EC, but fail to provide ECDT */
1020         printk(KERN_DEBUG PREFIX "Look up EC in DSDT\n");
1021         status = acpi_get_devices(ec_device_ids[0].id, ec_parse_device,
1022                                         boot_ec, NULL);
1023         /* Check that acpi_get_devices actually find something */
1024         if (ACPI_FAILURE(status) || !boot_ec->handle)
1025                 goto error;
1026         /* We really need to limit this workaround, the only ASUS,
1027          * which needs it, has fake EC._INI method, so use it as flag.
1028          * Keep boot_ec struct as it will be needed soon.
1029          */
1030         if (!dmi_name_in_vendors("ASUS") ||
1031             ACPI_FAILURE(acpi_get_handle(boot_ec->handle, "_INI", &dummy)))
1032                 return -ENODEV;
1033 install:
1034         if (!ec_install_handlers(boot_ec)) {
1035                 first_ec = boot_ec;
1036                 return 0;
1037         }
1038 error:
1039         kfree(boot_ec);
1040         boot_ec = NULL;
1041         return -ENODEV;
1042 }
1043
1044 static int acpi_ec_suspend(struct acpi_device *device, pm_message_t state)
1045 {
1046         struct acpi_ec *ec = acpi_driver_data(device);
1047         /* Stop using GPE */
1048         set_bit(EC_FLAGS_NO_GPE, &ec->flags);
1049         clear_bit(EC_FLAGS_GPE_MODE, &ec->flags);
1050         acpi_disable_gpe(NULL, ec->gpe);
1051         return 0;
1052 }
1053
1054 static int acpi_ec_resume(struct acpi_device *device)
1055 {
1056         struct acpi_ec *ec = acpi_driver_data(device);
1057         /* Enable use of GPE back */
1058         clear_bit(EC_FLAGS_NO_GPE, &ec->flags);
1059         acpi_enable_gpe(NULL, ec->gpe);
1060         return 0;
1061 }
1062
1063 static struct acpi_driver acpi_ec_driver = {
1064         .name = "ec",
1065         .class = ACPI_EC_CLASS,
1066         .ids = ec_device_ids,
1067         .ops = {
1068                 .add = acpi_ec_add,
1069                 .remove = acpi_ec_remove,
1070                 .start = acpi_ec_start,
1071                 .stop = acpi_ec_stop,
1072                 .suspend = acpi_ec_suspend,
1073                 .resume = acpi_ec_resume,
1074                 },
1075 };
1076
1077 static int __init acpi_ec_init(void)
1078 {
1079         int result = 0;
1080
1081         if (acpi_disabled)
1082                 return 0;
1083
1084         acpi_ec_dir = proc_mkdir(ACPI_EC_CLASS, acpi_root_dir);
1085         if (!acpi_ec_dir)
1086                 return -ENODEV;
1087
1088         /* Now register the driver for the EC */
1089         result = acpi_bus_register_driver(&acpi_ec_driver);
1090         if (result < 0) {
1091                 remove_proc_entry(ACPI_EC_CLASS, acpi_root_dir);
1092                 return -ENODEV;
1093         }
1094
1095         return result;
1096 }
1097
1098 subsys_initcall(acpi_ec_init);
1099
1100 /* EC driver currently not unloadable */
1101 #if 0
1102 static void __exit acpi_ec_exit(void)
1103 {
1104
1105         acpi_bus_unregister_driver(&acpi_ec_driver);
1106
1107         remove_proc_entry(ACPI_EC_CLASS, acpi_root_dir);
1108
1109         return;
1110 }
1111 #endif  /* 0 */