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 8       /* 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 wi;
 104         u8 ri;
 105         u8 wlen;
 106         u8 rlen;
 107         bool done;
 108 };
 109
 110 static struct acpi_ec {
 111         acpi_handle handle;
 112         unsigned long gpe;
 113         unsigned long command_addr;
 114         unsigned long data_addr;
 115         unsigned long global_lock;
 116         unsigned long flags;
 117         struct mutex lock;
 118         wait_queue_head_t wait;
 119         struct list_head list;
 120         struct transaction *curr;
 121         spinlock_t curr_lock;
 122 } *boot_ec, *first_ec;
 123
 124 /*
 125  * Some Asus system have exchanged ECDT data/command IO addresses.
 126  */
 127 static int print_ecdt_error(const struct dmi_system_id *id)
 128 {
 129         printk(KERN_NOTICE PREFIX "%s detected - "
 130                 "ECDT has exchanged control/data I/O address\n",
 131                 id->ident);
 132         return 0;
 133 }
 134
 135 static struct dmi_system_id __cpuinitdata ec_dmi_table[] = {
 136         {
 137         print_ecdt_error, "Asus L4R", {
 138         DMI_MATCH(DMI_BIOS_VERSION, "1008.006"),
 139         DMI_MATCH(DMI_PRODUCT_NAME, "L4R"),
 140         DMI_MATCH(DMI_BOARD_NAME, "L4R") }, NULL},
 141         {
 142         print_ecdt_error, "Asus M6R", {
 143         DMI_MATCH(DMI_BIOS_VERSION, "0207"),
 144         DMI_MATCH(DMI_PRODUCT_NAME, "M6R"),
 145         DMI_MATCH(DMI_BOARD_NAME, "M6R") }, NULL},
 146         {},
 147 };
 148
 149 /* --------------------------------------------------------------------------
 150                              Transaction Management
 151    -------------------------------------------------------------------------- */
 152
 153 static inline u8 acpi_ec_read_status(struct acpi_ec *ec)
 154 {
 155         u8 x = inb(ec->command_addr);
 156         pr_debug(PREFIX "---> status = 0x%2.2x\n", x);
 157         return x;
 158 }
 159
 160 static inline u8 acpi_ec_read_data(struct acpi_ec *ec)
 161 {
 162         u8 x = inb(ec->data_addr);
 163         pr_debug(PREFIX "---> data = 0x%2.2x\n", x);
 164         return x;
 165 }
 166
 167 static inline void acpi_ec_write_cmd(struct acpi_ec *ec, u8 command)
 168 {
 169         pr_debug(PREFIX "<--- command = 0x%2.2x\n", command);
 170         outb(command, ec->command_addr);
 171 }
 172
 173 static inline void acpi_ec_write_data(struct acpi_ec *ec, u8 data)
 174 {
 175         pr_debug(PREFIX "<--- data = 0x%2.2x\n", data);
 176         outb(data, ec->data_addr);
 177 }
 178
 179 static int ec_transaction_done(struct acpi_ec *ec)
 180 {
 181         unsigned long flags;
 182         int ret = 0;
 183         spin_lock_irqsave(&ec->curr_lock, flags);
 184         if (!ec->curr || ec->curr->done)
 185                 ret = 1;
 186         spin_unlock_irqrestore(&ec->curr_lock, flags);
 187         return ret;
 188 }
 189
 190 static void start_transaction(struct acpi_ec *ec)
 191 {
 192         ec->curr->irq_count = ec->curr->wi = ec->curr->ri = 0;
 193         ec->curr->done = false;
 194         acpi_ec_write_cmd(ec, ec->curr->command);
 195 }
 196
 197 static void gpe_transaction(struct acpi_ec *ec, u8 status)
 198 {
 199         unsigned long flags;
 200         spin_lock_irqsave(&ec->curr_lock, flags);
 201         if (!ec->curr)
 202                 goto unlock;
 203         if (ec->curr->wlen > ec->curr->wi) {
 204                 if ((status & ACPI_EC_FLAG_IBF) == 0)
 205                         acpi_ec_write_data(ec,
 206                                 ec->curr->wdata[ec->curr->wi++]);
 207                 else
 208                         goto err;
 209         } else if (ec->curr->rlen > ec->curr->ri) {
 210                 if ((status & ACPI_EC_FLAG_OBF) == 1) {
 211                         ec->curr->rdata[ec->curr->ri++] = acpi_ec_read_data(ec);
 212                         if (ec->curr->rlen == ec->curr->ri)
 213                                 ec->curr->done = true;
 214                 } else
 215                         goto err;
 216         } else if (ec->curr->wlen == ec->curr->wi &&
 217                    (status & ACPI_EC_FLAG_IBF) == 0)
 218                 ec->curr->done = true;
 219         goto unlock;
 220 err:
 221         /* false interrupt, state didn't change */
 222         if (in_interrupt())
 223                 ++ec->curr->irq_count;
 224 unlock:
 225         spin_unlock_irqrestore(&ec->curr_lock, flags);
 226 }
 227
 228 static int acpi_ec_wait(struct acpi_ec *ec)
 229 {
 230         if (wait_event_timeout(ec->wait, ec_transaction_done(ec),
 231                                msecs_to_jiffies(ACPI_EC_DELAY)))
 232                 return 0;
 233         /* try restart command if we get any false interrupts */
 234         if (ec->curr->irq_count &&
 235             (acpi_ec_read_status(ec) & ACPI_EC_FLAG_IBF) == 0) {
 236                 pr_debug(PREFIX "controller reset, restart transaction\n");
 237                 start_transaction(ec);
 238                 if (wait_event_timeout(ec->wait, ec_transaction_done(ec),
 239                                         msecs_to_jiffies(ACPI_EC_DELAY)))
 240                         return 0;
 241         }
 242         /* missing GPEs, switch back to poll mode */
 243         if (printk_ratelimit())
 244                 pr_info(PREFIX "missing confirmations, "
 245                                 "switch off interrupt mode.\n");
 246         set_bit(EC_FLAGS_NO_GPE, &ec->flags);
 247         clear_bit(EC_FLAGS_GPE_MODE, &ec->flags);
 248         return 1;
 249 }
 250
 251 static void acpi_ec_gpe_query(void *ec_cxt);
 252
 253 static int ec_check_sci(struct acpi_ec *ec, u8 state)
 254 {
 255         if (state & ACPI_EC_FLAG_SCI) {
 256                 if (!test_and_set_bit(EC_FLAGS_QUERY_PENDING, &ec->flags))
 257                         return acpi_os_execute(OSL_EC_BURST_HANDLER,
 258                                 acpi_ec_gpe_query, ec);
 259         }
 260         return 0;
 261 }
 262
 263 static int ec_poll(struct acpi_ec *ec)
 264 {
 265         unsigned long delay = jiffies + msecs_to_jiffies(ACPI_EC_DELAY);
 266         udelay(ACPI_EC_UDELAY);
 267         while (time_before(jiffies, delay)) {
 268                 gpe_transaction(ec, acpi_ec_read_status(ec));
 269                 udelay(ACPI_EC_UDELAY);
 270                 if (ec_transaction_done(ec))
 271                         return 0;
 272         }
 273         return -ETIME;
 274 }
 275
 276 static int acpi_ec_transaction_unlocked(struct acpi_ec *ec,
 277                                         struct transaction *t,
 278                                         int force_poll)
 279 {
 280         unsigned long tmp;
 281         int ret = 0;
 282         pr_debug(PREFIX "transaction start\n");
 283         /* disable GPE during transaction if storm is detected */
 284         if (test_bit(EC_FLAGS_GPE_STORM, &ec->flags)) {
 285                 clear_bit(EC_FLAGS_GPE_MODE, &ec->flags);
 286                 acpi_disable_gpe(NULL, ec->gpe);
 287         }
 288         /* start transaction */
 289         spin_lock_irqsave(&ec->curr_lock, tmp);
 290         /* following two actions should be kept atomic */
 291         ec->curr = t;
 292         start_transaction(ec);
 293         if (ec->curr->command == ACPI_EC_COMMAND_QUERY)
 294                 clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags);
 295         spin_unlock_irqrestore(&ec->curr_lock, tmp);
 296         /* if we selected poll mode or failed in GPE-mode do a poll loop */
 297         if (force_poll ||
 298             !test_bit(EC_FLAGS_GPE_MODE, &ec->flags) ||
 299             acpi_ec_wait(ec))
 300                 ret = ec_poll(ec);
 301         pr_debug(PREFIX "transaction end\n");
 302         spin_lock_irqsave(&ec->curr_lock, tmp);
 303         ec->curr = NULL;
 304         spin_unlock_irqrestore(&ec->curr_lock, tmp);
 305         if (test_bit(EC_FLAGS_GPE_STORM, &ec->flags)) {
 306                 /* check if we received SCI during transaction */
 307                 ec_check_sci(ec, acpi_ec_read_status(ec));
 308                 /* it is safe to enable GPE outside of transaction */
 309                 acpi_enable_gpe(NULL, ec->gpe);
 310         } else if (test_bit(EC_FLAGS_GPE_MODE, &ec->flags) &&
 311                    t->irq_count > ACPI_EC_STORM_THRESHOLD) {
 312                 pr_info(PREFIX "GPE storm detected, "
 313                         "transactions will use polling mode\n");
 314                 set_bit(EC_FLAGS_GPE_STORM, &ec->flags);
 315         }
 316         return ret;
 317 }
 318
 319 static int ec_check_ibf0(struct acpi_ec *ec)
 320 {
 321         u8 status = acpi_ec_read_status(ec);
 322         return (status & ACPI_EC_FLAG_IBF) == 0;
 323 }
 324
 325 static int ec_wait_ibf0(struct acpi_ec *ec)
 326 {
 327         unsigned long delay = jiffies + msecs_to_jiffies(ACPI_EC_DELAY);
 328         /* interrupt wait manually if GPE mode is not active */
 329         unsigned long timeout = test_bit(EC_FLAGS_GPE_MODE, &ec->flags) ?
 330                 msecs_to_jiffies(ACPI_EC_DELAY) : msecs_to_jiffies(1);
 331         while (time_before(jiffies, delay))
 332                 if (wait_event_timeout(ec->wait, ec_check_ibf0(ec), timeout))
 333                         return 0;
 334         return -ETIME;
 335 }
 336
 337 static int acpi_ec_transaction(struct acpi_ec *ec, struct transaction *t,
 338                                int force_poll)
 339 {
 340         int status;
 341         u32 glk;
 342         if (!ec || (!t) || (t->wlen && !t->wdata) || (t->rlen && !t->rdata))
 343                 return -EINVAL;
 344         if (t->rdata)
 345                 memset(t->rdata, 0, t->rlen);
 346         mutex_lock(&ec->lock);
 347         if (ec->global_lock) {
 348                 status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk);
 349                 if (ACPI_FAILURE(status)) {
 350                         status = -ENODEV;
 351                         goto unlock;
 352                 }
 353         }
 354         if (ec_wait_ibf0(ec)) {
 355                 pr_err(PREFIX "input buffer is not empty, "
 356                                 "aborting transaction\n");
 357                 status = -ETIME;
 358                 goto end;
 359         }
 360         status = acpi_ec_transaction_unlocked(ec, t, force_poll);
 361 end:
 362         if (ec->global_lock)
 363                 acpi_release_global_lock(glk);
 364 unlock:
 365         mutex_unlock(&ec->lock);
 366         return status;
 367 }
 368
 369 /*
 370  * Note: samsung nv5000 doesn't work with ec burst mode.
 371  * http://bugzilla.kernel.org/show_bug.cgi?id=4980
 372  */
 373 int acpi_ec_burst_enable(struct acpi_ec *ec)
 374 {
 375         u8 d;
 376         struct transaction t = {.command = ACPI_EC_BURST_ENABLE,
 377                                 .wdata = NULL, .rdata = &d,
 378                                 .wlen = 0, .rlen = 1};
 379
 380         return acpi_ec_transaction(ec, &t, 0);
 381 }
 382
 383 int acpi_ec_burst_disable(struct acpi_ec *ec)
 384 {
 385         struct transaction t = {.command = ACPI_EC_BURST_DISABLE,
 386                                 .wdata = NULL, .rdata = NULL,
 387                                 .wlen = 0, .rlen = 0};
 388
 389         return (acpi_ec_read_status(ec) & ACPI_EC_FLAG_BURST) ?
 390                                 acpi_ec_transaction(ec, &t, 0) : 0;
 391 }
 392
 393 static int acpi_ec_read(struct acpi_ec *ec, u8 address, u8 * data)
 394 {
 395         int result;
 396         u8 d;
 397         struct transaction t = {.command = ACPI_EC_COMMAND_READ,
 398                                 .wdata = &address, .rdata = &d,
 399                                 .wlen = 1, .rlen = 1};
 400
 401         result = acpi_ec_transaction(ec, &t, 0);
 402         *data = d;
 403         return result;
 404 }
 405
 406 static int acpi_ec_write(struct acpi_ec *ec, u8 address, u8 data)
 407 {
 408         u8 wdata[2] = { address, data };
 409         struct transaction t = {.command = ACPI_EC_COMMAND_WRITE,
 410                                 .wdata = wdata, .rdata = NULL,
 411                                 .wlen = 2, .rlen = 0};
 412
 413         return acpi_ec_transaction(ec, &t, 0);
 414 }
 415
 416 /*
 417  * Externally callable EC access functions. For now, assume 1 EC only
 418  */
 419 int ec_burst_enable(void)
 420 {
 421         if (!first_ec)
 422                 return -ENODEV;
 423         return acpi_ec_burst_enable(first_ec);
 424 }
 425
 426 EXPORT_SYMBOL(ec_burst_enable);
 427
 428 int ec_burst_disable(void)
 429 {
 430         if (!first_ec)
 431                 return -ENODEV;
 432         return acpi_ec_burst_disable(first_ec);
 433 }
 434
 435 EXPORT_SYMBOL(ec_burst_disable);
 436
 437 int ec_read(u8 addr, u8 * val)
 438 {
 439         int err;
 440         u8 temp_data;
 441
 442         if (!first_ec)
 443                 return -ENODEV;
 444
 445         err = acpi_ec_read(first_ec, addr, &temp_data);
 446
 447         if (!err) {
 448                 *val = temp_data;
 449                 return 0;
 450         } else
 451                 return err;
 452 }
 453
 454 EXPORT_SYMBOL(ec_read);
 455
 456 int ec_write(u8 addr, u8 val)
 457 {
 458         int err;
 459
 460         if (!first_ec)
 461                 return -ENODEV;
 462
 463         err = acpi_ec_write(first_ec, addr, val);
 464
 465         return err;
 466 }
 467
 468 EXPORT_SYMBOL(ec_write);
 469
 470 int ec_transaction(u8 command,
 471                    const u8 * wdata, unsigned wdata_len,
 472                    u8 * rdata, unsigned rdata_len,
 473                    int force_poll)
 474 {
 475         struct transaction t = {.command = command,
 476                                 .wdata = wdata, .rdata = rdata,
 477                                 .wlen = wdata_len, .rlen = rdata_len};
 478         if (!first_ec)
 479                 return -ENODEV;
 480
 481         return acpi_ec_transaction(first_ec, &t, force_poll);
 482 }
 483
 484 EXPORT_SYMBOL(ec_transaction);
 485
 486 static int acpi_ec_query(struct acpi_ec *ec, u8 * data)
 487 {
 488         int result;
 489         u8 d;
 490         struct transaction t = {.command = ACPI_EC_COMMAND_QUERY,
 491                                 .wdata = NULL, .rdata = &d,
 492                                 .wlen = 0, .rlen = 1};
 493         if (!ec || !data)
 494                 return -EINVAL;
 495
 496         /*
 497          * Query the EC to find out which _Qxx method we need to evaluate.
 498          * Note that successful completion of the query causes the ACPI_EC_SCI
 499          * bit to be cleared (and thus clearing the interrupt source).
 500          */
 501
 502         result = acpi_ec_transaction(ec, &t, 0);
 503         if (result)
 504                 return result;
 505
 506         if (!d)
 507                 return -ENODATA;
 508
 509         *data = d;
 510         return 0;
 511 }
 512
 513 /* --------------------------------------------------------------------------
 514                                 Event Management
 515    -------------------------------------------------------------------------- */
 516 int acpi_ec_add_query_handler(struct acpi_ec *ec, u8 query_bit,
 517                               acpi_handle handle, acpi_ec_query_func func,
 518                               void *data)
 519 {
 520         struct acpi_ec_query_handler *handler =
 521             kzalloc(sizeof(struct acpi_ec_query_handler), GFP_KERNEL);
 522         if (!handler)
 523                 return -ENOMEM;
 524
 525         handler->query_bit = query_bit;
 526         handler->handle = handle;
 527         handler->func = func;
 528         handler->data = data;
 529         mutex_lock(&ec->lock);
 530         list_add(&handler->node, &ec->list);
 531         mutex_unlock(&ec->lock);
 532         return 0;
 533 }
 534
 535 EXPORT_SYMBOL_GPL(acpi_ec_add_query_handler);
 536
 537 void acpi_ec_remove_query_handler(struct acpi_ec *ec, u8 query_bit)
 538 {
 539         struct acpi_ec_query_handler *handler, *tmp;
 540         mutex_lock(&ec->lock);
 541         list_for_each_entry_safe(handler, tmp, &ec->list, node) {
 542                 if (query_bit == handler->query_bit) {
 543                         list_del(&handler->node);
 544                         kfree(handler);
 545                 }
 546         }
 547         mutex_unlock(&ec->lock);
 548 }
 549
 550 EXPORT_SYMBOL_GPL(acpi_ec_remove_query_handler);
 551
 552 static void acpi_ec_gpe_query(void *ec_cxt)
 553 {
 554         struct acpi_ec *ec = ec_cxt;
 555         u8 value = 0;
 556         struct acpi_ec_query_handler *handler, copy;
 557
 558         if (!ec || acpi_ec_query(ec, &value))
 559                 return;
 560         mutex_lock(&ec->lock);
 561         list_for_each_entry(handler, &ec->list, node) {
 562                 if (value == handler->query_bit) {
 563                         /* have custom handler for this bit */
 564                         memcpy(&copy, handler, sizeof(copy));
 565                         mutex_unlock(&ec->lock);
 566                         if (copy.func) {
 567                                 copy.func(copy.data);
 568                         } else if (copy.handle) {
 569                                 acpi_evaluate_object(copy.handle, NULL, NULL, NULL);
 570                         }
 571                         return;
 572                 }
 573         }
 574         mutex_unlock(&ec->lock);
 575 }
 576
 577 static u32 acpi_ec_gpe_handler(void *data)
 578 {
 579         struct acpi_ec *ec = data;
 580         u8 status;
 581
 582         pr_debug(PREFIX "~~~> interrupt\n");
 583         status = acpi_ec_read_status(ec);
 584
 585         if (test_bit(EC_FLAGS_GPE_MODE, &ec->flags)) {
 586                 gpe_transaction(ec, status);
 587                 if (ec_transaction_done(ec) &&
 588                     (status & ACPI_EC_FLAG_IBF) == 0)
 589                         wake_up(&ec->wait);
 590         }
 591
 592         ec_check_sci(ec, status);
 593         if (!test_bit(EC_FLAGS_GPE_MODE, &ec->flags) &&
 594             !test_bit(EC_FLAGS_NO_GPE, &ec->flags)) {
 595                 /* this is non-query, must be confirmation */
 596                 if (!test_bit(EC_FLAGS_GPE_STORM, &ec->flags)) {
 597                         if (printk_ratelimit())
 598                                 pr_info(PREFIX "non-query interrupt received,"
 599                                         " switching to interrupt mode\n");
 600                 } else {
 601                         /* hush, STORM switches the mode every transaction */
 602                         pr_debug(PREFIX "non-query interrupt received,"
 603                                 " switching to interrupt mode\n");
 604                 }
 605                 set_bit(EC_FLAGS_GPE_MODE, &ec->flags);
 606         }
 607         return ACPI_INTERRUPT_HANDLED;
 608 }
 609
 610 /* --------------------------------------------------------------------------
 611                              Address Space Management
 612    -------------------------------------------------------------------------- */
 613
 614 static acpi_status
 615 acpi_ec_space_handler(u32 function, acpi_physical_address address,
 616                       u32 bits, acpi_integer *value,
 617                       void *handler_context, void *region_context)
 618 {
 619         struct acpi_ec *ec = handler_context;
 620         int result = 0, i;
 621         u8 temp = 0;
 622
 623         if ((address > 0xFF) || !value || !handler_context)
 624                 return AE_BAD_PARAMETER;
 625
 626         if (function != ACPI_READ && function != ACPI_WRITE)
 627                 return AE_BAD_PARAMETER;
 628
 629         if (bits != 8 && acpi_strict)
 630                 return AE_BAD_PARAMETER;
 631
 632         acpi_ec_burst_enable(ec);
 633
 634         if (function == ACPI_READ) {
 635                 result = acpi_ec_read(ec, address, &temp);
 636                 *value = temp;
 637         } else {
 638                 temp = 0xff & (*value);
 639                 result = acpi_ec_write(ec, address, temp);
 640         }
 641
 642         for (i = 8; unlikely(bits - i > 0); i += 8) {
 643                 ++address;
 644                 if (function == ACPI_READ) {
 645                         result = acpi_ec_read(ec, address, &temp);
 646                         (*value) |= ((acpi_integer)temp) << i;
 647                 } else {
 648                         temp = 0xff & ((*value) >> i);
 649                         result = acpi_ec_write(ec, address, temp);
 650                 }
 651         }
 652
 653         acpi_ec_burst_disable(ec);
 654
 655         switch (result) {
 656         case -EINVAL:
 657                 return AE_BAD_PARAMETER;
 658                 break;
 659         case -ENODEV:
 660                 return AE_NOT_FOUND;
 661                 break;
 662         case -ETIME:
 663                 return AE_TIME;
 664                 break;
 665         default:
 666                 return AE_OK;
 667         }
 668 }
 669
 670 /* --------------------------------------------------------------------------
 671                               FS Interface (/proc)
 672    -------------------------------------------------------------------------- */
 673
 674 static struct proc_dir_entry *acpi_ec_dir;
 675
 676 static int acpi_ec_read_info(struct seq_file *seq, void *offset)
 677 {
 678         struct acpi_ec *ec = seq->private;
 679
 680         if (!ec)
 681                 goto end;
 682
 683         seq_printf(seq, "gpe:\t\t\t0x%02x\n", (u32) ec->gpe);
 684         seq_printf(seq, "ports:\t\t\t0x%02x, 0x%02x\n",
 685                    (unsigned)ec->command_addr, (unsigned)ec->data_addr);
 686         seq_printf(seq, "use global lock:\t%s\n",
 687                    ec->global_lock ? "yes" : "no");
 688       end:
 689         return 0;
 690 }
 691
 692 static int acpi_ec_info_open_fs(struct inode *inode, struct file *file)
 693 {
 694         return single_open(file, acpi_ec_read_info, PDE(inode)->data);
 695 }
 696
 697 static struct file_operations acpi_ec_info_ops = {
 698         .open = acpi_ec_info_open_fs,
 699         .read = seq_read,
 700         .llseek = seq_lseek,
 701         .release = single_release,
 702         .owner = THIS_MODULE,
 703 };
 704
 705 static int acpi_ec_add_fs(struct acpi_device *device)
 706 {
 707         struct proc_dir_entry *entry = NULL;
 708
 709         if (!acpi_device_dir(device)) {
 710                 acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device),
 711                                                      acpi_ec_dir);
 712                 if (!acpi_device_dir(device))
 713                         return -ENODEV;
 714         }
 715
 716         entry = proc_create_data(ACPI_EC_FILE_INFO, S_IRUGO,
 717                                  acpi_device_dir(device),
 718                                  &acpi_ec_info_ops, acpi_driver_data(device));
 719         if (!entry)
 720                 return -ENODEV;
 721         return 0;
 722 }
 723
 724 static int acpi_ec_remove_fs(struct acpi_device *device)
 725 {
 726
 727         if (acpi_device_dir(device)) {
 728                 remove_proc_entry(ACPI_EC_FILE_INFO, acpi_device_dir(device));
 729                 remove_proc_entry(acpi_device_bid(device), acpi_ec_dir);
 730                 acpi_device_dir(device) = NULL;
 731         }
 732
 733         return 0;
 734 }
 735
 736 /* --------------------------------------------------------------------------
 737                                Driver Interface
 738    -------------------------------------------------------------------------- */
 739 static acpi_status
 740 ec_parse_io_ports(struct acpi_resource *resource, void *context);
 741
 742 static struct acpi_ec *make_acpi_ec(void)
 743 {
 744         struct acpi_ec *ec = kzalloc(sizeof(struct acpi_ec), GFP_KERNEL);
 745         if (!ec)
 746                 return NULL;
 747         ec->flags = 1 << EC_FLAGS_QUERY_PENDING;
 748         mutex_init(&ec->lock);
 749         init_waitqueue_head(&ec->wait);
 750         INIT_LIST_HEAD(&ec->list);
 751         spin_lock_init(&ec->curr_lock);
 752         return ec;
 753 }
 754
 755 static acpi_status
 756 acpi_ec_register_query_methods(acpi_handle handle, u32 level,
 757                                void *context, void **return_value)
 758 {
 759         struct acpi_namespace_node *node = handle;
 760         struct acpi_ec *ec = context;
 761         int value = 0;
 762         if (sscanf(node->name.ascii, "_Q%x", &value) == 1) {
 763                 acpi_ec_add_query_handler(ec, value, handle, NULL, NULL);
 764         }
 765         return AE_OK;
 766 }
 767
 768 static acpi_status
 769 ec_parse_device(acpi_handle handle, u32 Level, void *context, void **retval)
 770 {
 771         acpi_status status;
 772         unsigned long long tmp = 0;
 773
 774         struct acpi_ec *ec = context;
 775         status = acpi_walk_resources(handle, METHOD_NAME__CRS,
 776                                      ec_parse_io_ports, ec);
 777         if (ACPI_FAILURE(status))
 778                 return status;
 779
 780         /* Get GPE bit assignment (EC events). */
 781         /* TODO: Add support for _GPE returning a package */
 782         status = acpi_evaluate_integer(handle, "_GPE", NULL, &tmp);
 783         if (ACPI_FAILURE(status))
 784                 return status;
 785         ec->gpe = tmp;
 786         /* Use the global lock for all EC transactions? */
 787         tmp = 0;
 788         acpi_evaluate_integer(handle, "_GLK", NULL, &tmp);
 789         ec->global_lock = tmp;
 790         ec->handle = handle;
 791         return AE_CTRL_TERMINATE;
 792 }
 793
 794 static void ec_remove_handlers(struct acpi_ec *ec)
 795 {
 796         if (ACPI_FAILURE(acpi_remove_address_space_handler(ec->handle,
 797                                 ACPI_ADR_SPACE_EC, &acpi_ec_space_handler)))
 798                 pr_err(PREFIX "failed to remove space handler\n");
 799         if (ACPI_FAILURE(acpi_remove_gpe_handler(NULL, ec->gpe,
 800                                 &acpi_ec_gpe_handler)))
 801                 pr_err(PREFIX "failed to remove gpe handler\n");
 802         clear_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags);
 803 }
 804
 805 static int acpi_ec_add(struct acpi_device *device)
 806 {
 807         struct acpi_ec *ec = NULL;
 808
 809         if (!device)
 810                 return -EINVAL;
 811         strcpy(acpi_device_name(device), ACPI_EC_DEVICE_NAME);
 812         strcpy(acpi_device_class(device), ACPI_EC_CLASS);
 813
 814         /* Check for boot EC */
 815         if (boot_ec &&
 816             (boot_ec->handle == device->handle ||
 817              boot_ec->handle == ACPI_ROOT_OBJECT)) {
 818                 ec = boot_ec;
 819                 boot_ec = NULL;
 820         } else {
 821                 ec = make_acpi_ec();
 822                 if (!ec)
 823                         return -ENOMEM;
 824                 if (ec_parse_device(device->handle, 0, ec, NULL) !=
 825                     AE_CTRL_TERMINATE) {
 826                         kfree(ec);
 827                         return -EINVAL;
 828                 }
 829         }
 830
 831         ec->handle = device->handle;
 832
 833         /* Find and register all query methods */
 834         acpi_walk_namespace(ACPI_TYPE_METHOD, ec->handle, 1,
 835                             acpi_ec_register_query_methods, ec, NULL);
 836
 837         if (!first_ec)
 838                 first_ec = ec;
 839         device->driver_data = ec;
 840         acpi_ec_add_fs(device);
 841         pr_info(PREFIX "GPE = 0x%lx, I/O: command/status = 0x%lx, data = 0x%lx\n",
 842                           ec->gpe, ec->command_addr, ec->data_addr);
 843         pr_info(PREFIX "driver started in %s mode\n",
 844                 (test_bit(EC_FLAGS_GPE_MODE, &ec->flags))?"interrupt":"poll");
 845         return 0;
 846 }
 847
 848 static int acpi_ec_remove(struct acpi_device *device, int type)
 849 {
 850         struct acpi_ec *ec;
 851         struct acpi_ec_query_handler *handler, *tmp;
 852
 853         if (!device)
 854                 return -EINVAL;
 855
 856         ec = acpi_driver_data(device);
 857         mutex_lock(&ec->lock);
 858         list_for_each_entry_safe(handler, tmp, &ec->list, node) {
 859                 list_del(&handler->node);
 860                 kfree(handler);
 861         }
 862         mutex_unlock(&ec->lock);
 863         acpi_ec_remove_fs(device);
 864         device->driver_data = NULL;
 865         if (ec == first_ec)
 866                 first_ec = NULL;
 867         kfree(ec);
 868         return 0;
 869 }
 870
 871 static acpi_status
 872 ec_parse_io_ports(struct acpi_resource *resource, void *context)
 873 {
 874         struct acpi_ec *ec = context;
 875
 876         if (resource->type != ACPI_RESOURCE_TYPE_IO)
 877                 return AE_OK;
 878
 879         /*
 880          * The first address region returned is the data port, and
 881          * the second address region returned is the status/command
 882          * port.
 883          */
 884         if (ec->data_addr == 0)
 885                 ec->data_addr = resource->data.io.minimum;
 886         else if (ec->command_addr == 0)
 887                 ec->command_addr = resource->data.io.minimum;
 888         else
 889                 return AE_CTRL_TERMINATE;
 890
 891         return AE_OK;
 892 }
 893
 894 static int ec_install_handlers(struct acpi_ec *ec)
 895 {
 896         acpi_status status;
 897         if (test_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags))
 898                 return 0;
 899         status = acpi_install_gpe_handler(NULL, ec->gpe,
 900                                   ACPI_GPE_EDGE_TRIGGERED,
 901                                   &acpi_ec_gpe_handler, ec);
 902         if (ACPI_FAILURE(status))
 903                 return -ENODEV;
 904         acpi_set_gpe_type(NULL, ec->gpe, ACPI_GPE_TYPE_RUNTIME);
 905         acpi_enable_gpe(NULL, ec->gpe);
 906         status = acpi_install_address_space_handler(ec->handle,
 907                                                     ACPI_ADR_SPACE_EC,
 908                                                     &acpi_ec_space_handler,
 909                                                     NULL, ec);
 910         if (ACPI_FAILURE(status)) {
 911                 if (status == AE_NOT_FOUND) {
 912                         /*
 913                          * Maybe OS fails in evaluating the _REG object.
 914                          * The AE_NOT_FOUND error will be ignored and OS
 915                          * continue to initialize EC.
 916                          */
 917                         printk(KERN_ERR "Fail in evaluating the _REG object"
 918                                 " of EC device. Broken bios is suspected.\n");
 919                 } else {
 920                         acpi_remove_gpe_handler(NULL, ec->gpe,
 921                                 &acpi_ec_gpe_handler);
 922                         return -ENODEV;
 923                 }
 924         }
 925
 926         set_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags);
 927         return 0;
 928 }
 929
 930 static int acpi_ec_start(struct acpi_device *device)
 931 {
 932         struct acpi_ec *ec;
 933         int ret = 0;
 934
 935         if (!device)
 936                 return -EINVAL;
 937
 938         ec = acpi_driver_data(device);
 939
 940         if (!ec)
 941                 return -EINVAL;
 942
 943         ret = ec_install_handlers(ec);
 944
 945         /* EC is fully operational, allow queries */
 946         clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags);
 947         return ret;
 948 }
 949
 950 static int acpi_ec_stop(struct acpi_device *device, int type)
 951 {
 952         struct acpi_ec *ec;
 953         if (!device)
 954                 return -EINVAL;
 955         ec = acpi_driver_data(device);
 956         if (!ec)
 957                 return -EINVAL;
 958         ec_remove_handlers(ec);
 959
 960         return 0;
 961 }
 962
 963 int __init acpi_boot_ec_enable(void)
 964 {
 965         if (!boot_ec || test_bit(EC_FLAGS_HANDLERS_INSTALLED, &boot_ec->flags))
 966                 return 0;
 967         if (!ec_install_handlers(boot_ec)) {
 968                 first_ec = boot_ec;
 969                 return 0;
 970         }
 971         return -EFAULT;
 972 }
 973
 974 static const struct acpi_device_id ec_device_ids[] = {
 975         {"PNP0C09", 0},
 976         {"", 0},
 977 };
 978
 979 int __init acpi_ec_ecdt_probe(void)
 980 {
 981         int ret;
 982         acpi_status status;
 983         struct acpi_table_ecdt *ecdt_ptr;
 984
 985         boot_ec = make_acpi_ec();
 986         if (!boot_ec)
 987                 return -ENOMEM;
 988         /*
 989          * Generate a boot ec context
 990          */
 991         status = acpi_get_table(ACPI_SIG_ECDT, 1,
 992                                 (struct acpi_table_header **)&ecdt_ptr);
 993         if (ACPI_SUCCESS(status)) {
 994                 pr_info(PREFIX "EC description table is found, configuring boot EC\n");
 995                 boot_ec->command_addr = ecdt_ptr->control.address;
 996                 boot_ec->data_addr = ecdt_ptr->data.address;
 997                 if (dmi_check_system(ec_dmi_table)) {
 998                         /*
 999                          * If the board falls into ec_dmi_table, it means
1000                          * that ECDT table gives the incorrect command/status
1001                          * & data I/O address. Just fix it.
1002                          */
1003                         boot_ec->data_addr = ecdt_ptr->control.address;
1004                         boot_ec->command_addr = ecdt_ptr->data.address;
1005                 }
1006                 boot_ec->gpe = ecdt_ptr->gpe;
1007                 boot_ec->handle = ACPI_ROOT_OBJECT;
1008                 acpi_get_handle(ACPI_ROOT_OBJECT, ecdt_ptr->id, &boot_ec->handle);
1009         } else {
1010                 /* This workaround is needed only on some broken machines,
1011                  * which require early EC, but fail to provide ECDT */
1012                 acpi_handle x;
1013                 printk(KERN_DEBUG PREFIX "Look up EC in DSDT\n");
1014                 status = acpi_get_devices(ec_device_ids[0].id, ec_parse_device,
1015                                                 boot_ec, NULL);
1016                 /* Check that acpi_get_devices actually find something */
1017                 if (ACPI_FAILURE(status) || !boot_ec->handle)
1018                         goto error;
1019                 /* We really need to limit this workaround, the only ASUS,
1020                  * which needs it, has fake EC._INI method, so use it as flag.
1021                  * Keep boot_ec struct as it will be needed soon.
1022                  */
1023                 if (ACPI_FAILURE(acpi_get_handle(boot_ec->handle, "_INI", &x)))
1024                         return -ENODEV;
1025         }
1026
1027         ret = ec_install_handlers(boot_ec);
1028         if (!ret) {
1029                 first_ec = boot_ec;
1030                 return 0;
1031         }
1032       error:
1033         kfree(boot_ec);
1034         boot_ec = NULL;
1035         return -ENODEV;
1036 }
1037
1038 static int acpi_ec_suspend(struct acpi_device *device, pm_message_t state)
1039 {
1040         struct acpi_ec *ec = acpi_driver_data(device);
1041         /* Stop using GPE */
1042         set_bit(EC_FLAGS_NO_GPE, &ec->flags);
1043         clear_bit(EC_FLAGS_GPE_MODE, &ec->flags);
1044         acpi_disable_gpe(NULL, ec->gpe);
1045         return 0;
1046 }
1047
1048 static int acpi_ec_resume(struct acpi_device *device)
1049 {
1050         struct acpi_ec *ec = acpi_driver_data(device);
1051         /* Enable use of GPE back */
1052         clear_bit(EC_FLAGS_NO_GPE, &ec->flags);
1053         acpi_enable_gpe(NULL, ec->gpe);
1054         return 0;
1055 }
1056
1057 static struct acpi_driver acpi_ec_driver = {
1058         .name = "ec",
1059         .class = ACPI_EC_CLASS,
1060         .ids = ec_device_ids,
1061         .ops = {
1062                 .add = acpi_ec_add,
1063                 .remove = acpi_ec_remove,
1064                 .start = acpi_ec_start,
1065                 .stop = acpi_ec_stop,
1066                 .suspend = acpi_ec_suspend,
1067                 .resume = acpi_ec_resume,
1068                 },
1069 };
1070
1071 static int __init acpi_ec_init(void)
1072 {
1073         int result = 0;
1074
1075         if (acpi_disabled)
1076                 return 0;
1077
1078         acpi_ec_dir = proc_mkdir(ACPI_EC_CLASS, acpi_root_dir);
1079         if (!acpi_ec_dir)
1080                 return -ENODEV;
1081
1082         /* Now register the driver for the EC */
1083         result = acpi_bus_register_driver(&acpi_ec_driver);
1084         if (result < 0) {
1085                 remove_proc_entry(ACPI_EC_CLASS, acpi_root_dir);
1086                 return -ENODEV;
1087         }
1088
1089         return result;
1090 }
1091
1092 subsys_initcall(acpi_ec_init);
1093
1094 /* EC driver currently not unloadable */
1095 #if 0
1096 static void __exit acpi_ec_exit(void)
1097 {
1098
1099         acpi_bus_unregister_driver(&acpi_ec_driver);
1100
1101         remove_proc_entry(ACPI_EC_CLASS, acpi_root_dir);
1102
1103         return;
1104 }
1105 #endif  /* 0 */