1 /* 2 * ec.c - ACPI Embedded Controller Driver (v3) 3 * 4 * Copyright (C) 2001-2015 Intel Corporation 5 * Author: 2014, 2015 Lv Zheng <lv.zheng@intel.com> 6 * 2006, 2007 Alexey Starikovskiy <alexey.y.starikovskiy@intel.com> 7 * 2006 Denis Sadykov <denis.m.sadykov@intel.com> 8 * 2004 Luming Yu <luming.yu@intel.com> 9 * 2001, 2002 Andy Grover <andrew.grover@intel.com> 10 * 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com> 11 * Copyright (C) 2008 Alexey Starikovskiy <astarikovskiy@suse.de> 12 * 13 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 14 * 15 * This program is free software; you can redistribute it and/or modify 16 * it under the terms of the GNU General Public License as published by 17 * the Free Software Foundation; either version 2 of the License, or (at 18 * your option) any later version. 19 * 20 * This program is distributed in the hope that it will be useful, but 21 * WITHOUT ANY WARRANTY; without even the implied warranty of 22 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 23 * General Public License for more details. 24 * 25 * You should have received a copy of the GNU General Public License along 26 * with this program; if not, write to the Free Software Foundation, Inc., 27 * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA. 28 * 29 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 30 */ 31 32 /* Uncomment next line to get verbose printout */ 33 /* #define DEBUG */ 34 #define pr_fmt(fmt) "ACPI : EC: " fmt 35 36 #include <linux/kernel.h> 37 #include <linux/module.h> 38 #include <linux/init.h> 39 #include <linux/types.h> 40 #include <linux/delay.h> 41 #include <linux/interrupt.h> 42 #include <linux/list.h> 43 #include <linux/spinlock.h> 44 #include <linux/slab.h> 45 #include <linux/acpi.h> 46 #include <linux/dmi.h> 47 #include <asm/io.h> 48 49 #include "internal.h" 50 51 #define ACPI_EC_CLASS "embedded_controller" 52 #define ACPI_EC_DEVICE_NAME "Embedded Controller" 53 #define ACPI_EC_FILE_INFO "info" 54 55 /* EC status register */ 56 #define ACPI_EC_FLAG_OBF 0x01 /* Output buffer full */ 57 #define ACPI_EC_FLAG_IBF 0x02 /* Input buffer full */ 58 #define ACPI_EC_FLAG_CMD 0x08 /* Input buffer contains a command */ 59 #define ACPI_EC_FLAG_BURST 0x10 /* burst mode */ 60 #define ACPI_EC_FLAG_SCI 0x20 /* EC-SCI occurred */ 61 62 /* 63 * The SCI_EVT clearing timing is not defined by the ACPI specification. 64 * This leads to lots of practical timing issues for the host EC driver. 65 * The following variations are defined (from the target EC firmware's 66 * perspective): 67 * STATUS: After indicating SCI_EVT edge triggered IRQ to the host, the 68 * target can clear SCI_EVT at any time so long as the host can see 69 * the indication by reading the status register (EC_SC). So the 70 * host should re-check SCI_EVT after the first time the SCI_EVT 71 * indication is seen, which is the same time the query request 72 * (QR_EC) is written to the command register (EC_CMD). SCI_EVT set 73 * at any later time could indicate another event. Normally such 74 * kind of EC firmware has implemented an event queue and will 75 * return 0x00 to indicate "no outstanding event". 76 * QUERY: After seeing the query request (QR_EC) written to the command 77 * register (EC_CMD) by the host and having prepared the responding 78 * event value in the data register (EC_DATA), the target can safely 79 * clear SCI_EVT because the target can confirm that the current 80 * event is being handled by the host. The host then should check 81 * SCI_EVT right after reading the event response from the data 82 * register (EC_DATA). 83 * EVENT: After seeing the event response read from the data register 84 * (EC_DATA) by the host, the target can clear SCI_EVT. As the 85 * target requires time to notice the change in the data register 86 * (EC_DATA), the host may be required to wait additional guarding 87 * time before checking the SCI_EVT again. Such guarding may not be 88 * necessary if the host is notified via another IRQ. 89 */ 90 #define ACPI_EC_EVT_TIMING_STATUS 0x00 91 #define ACPI_EC_EVT_TIMING_QUERY 0x01 92 #define ACPI_EC_EVT_TIMING_EVENT 0x02 93 94 /* EC commands */ 95 enum ec_command { 96 ACPI_EC_COMMAND_READ = 0x80, 97 ACPI_EC_COMMAND_WRITE = 0x81, 98 ACPI_EC_BURST_ENABLE = 0x82, 99 ACPI_EC_BURST_DISABLE = 0x83, 100 ACPI_EC_COMMAND_QUERY = 0x84, 101 }; 102 103 #define ACPI_EC_DELAY 500 /* Wait 500ms max. during EC ops */ 104 #define ACPI_EC_UDELAY_GLK 1000 /* Wait 1ms max. to get global lock */ 105 #define ACPI_EC_UDELAY_POLL 550 /* Wait 1ms for EC transaction polling */ 106 #define ACPI_EC_CLEAR_MAX 100 /* Maximum number of events to query 107 * when trying to clear the EC */ 108 109 enum { 110 EC_FLAGS_QUERY_PENDING, /* Query is pending */ 111 EC_FLAGS_QUERY_GUARDING, /* Guard for SCI_EVT check */ 112 EC_FLAGS_HANDLERS_INSTALLED, /* Handlers for GPE and 113 * OpReg are installed */ 114 EC_FLAGS_STARTED, /* Driver is started */ 115 EC_FLAGS_STOPPED, /* Driver is stopped */ 116 EC_FLAGS_COMMAND_STORM, /* GPE storms occurred to the 117 * current command processing */ 118 }; 119 120 #define ACPI_EC_COMMAND_POLL 0x01 /* Available for command byte */ 121 #define ACPI_EC_COMMAND_COMPLETE 0x02 /* Completed last byte */ 122 123 /* ec.c is compiled in acpi namespace so this shows up as acpi.ec_delay param */ 124 static unsigned int ec_delay __read_mostly = ACPI_EC_DELAY; 125 module_param(ec_delay, uint, 0644); 126 MODULE_PARM_DESC(ec_delay, "Timeout(ms) waited until an EC command completes"); 127 128 static bool ec_busy_polling __read_mostly; 129 module_param(ec_busy_polling, bool, 0644); 130 MODULE_PARM_DESC(ec_busy_polling, "Use busy polling to advance EC transaction"); 131 132 static unsigned int ec_polling_guard __read_mostly = ACPI_EC_UDELAY_POLL; 133 module_param(ec_polling_guard, uint, 0644); 134 MODULE_PARM_DESC(ec_polling_guard, "Guard time(us) between EC accesses in polling modes"); 135 136 static unsigned int ec_event_clearing __read_mostly = ACPI_EC_EVT_TIMING_QUERY; 137 138 /* 139 * If the number of false interrupts per one transaction exceeds 140 * this threshold, will think there is a GPE storm happened and 141 * will disable the GPE for normal transaction. 142 */ 143 static unsigned int ec_storm_threshold __read_mostly = 8; 144 module_param(ec_storm_threshold, uint, 0644); 145 MODULE_PARM_DESC(ec_storm_threshold, "Maxim false GPE numbers not considered as GPE storm"); 146 147 struct acpi_ec_query_handler { 148 struct list_head node; 149 acpi_ec_query_func func; 150 acpi_handle handle; 151 void *data; 152 u8 query_bit; 153 struct kref kref; 154 }; 155 156 struct transaction { 157 const u8 *wdata; 158 u8 *rdata; 159 unsigned short irq_count; 160 u8 command; 161 u8 wi; 162 u8 ri; 163 u8 wlen; 164 u8 rlen; 165 u8 flags; 166 }; 167 168 static int acpi_ec_query(struct acpi_ec *ec, u8 *data); 169 static void advance_transaction(struct acpi_ec *ec); 170 171 struct acpi_ec *boot_ec, *first_ec; 172 EXPORT_SYMBOL(first_ec); 173 174 static int EC_FLAGS_VALIDATE_ECDT; /* ASUStec ECDTs need to be validated */ 175 static int EC_FLAGS_SKIP_DSDT_SCAN; /* Not all BIOS survive early DSDT scan */ 176 static int EC_FLAGS_CLEAR_ON_RESUME; /* Needs acpi_ec_clear() on boot/resume */ 177 static int EC_FLAGS_QUERY_HANDSHAKE; /* Needs QR_EC issued when SCI_EVT set */ 178 179 /* -------------------------------------------------------------------------- 180 * Logging/Debugging 181 * -------------------------------------------------------------------------- */ 182 183 /* 184 * Splitters used by the developers to track the boundary of the EC 185 * handling processes. 186 */ 187 #ifdef DEBUG 188 #define EC_DBG_SEP " " 189 #define EC_DBG_DRV "+++++" 190 #define EC_DBG_STM "=====" 191 #define EC_DBG_REQ "*****" 192 #define EC_DBG_EVT "#####" 193 #else 194 #define EC_DBG_SEP "" 195 #define EC_DBG_DRV 196 #define EC_DBG_STM 197 #define EC_DBG_REQ 198 #define EC_DBG_EVT 199 #endif 200 201 #define ec_log_raw(fmt, ...) \ 202 pr_info(fmt "\n", ##__VA_ARGS__) 203 #define ec_dbg_raw(fmt, ...) \ 204 pr_debug(fmt "\n", ##__VA_ARGS__) 205 #define ec_log(filter, fmt, ...) \ 206 ec_log_raw(filter EC_DBG_SEP fmt EC_DBG_SEP filter, ##__VA_ARGS__) 207 #define ec_dbg(filter, fmt, ...) \ 208 ec_dbg_raw(filter EC_DBG_SEP fmt EC_DBG_SEP filter, ##__VA_ARGS__) 209 210 #define ec_log_drv(fmt, ...) \ 211 ec_log(EC_DBG_DRV, fmt, ##__VA_ARGS__) 212 #define ec_dbg_drv(fmt, ...) \ 213 ec_dbg(EC_DBG_DRV, fmt, ##__VA_ARGS__) 214 #define ec_dbg_stm(fmt, ...) \ 215 ec_dbg(EC_DBG_STM, fmt, ##__VA_ARGS__) 216 #define ec_dbg_req(fmt, ...) \ 217 ec_dbg(EC_DBG_REQ, fmt, ##__VA_ARGS__) 218 #define ec_dbg_evt(fmt, ...) \ 219 ec_dbg(EC_DBG_EVT, fmt, ##__VA_ARGS__) 220 #define ec_dbg_ref(ec, fmt, ...) \ 221 ec_dbg_raw("%lu: " fmt, ec->reference_count, ## __VA_ARGS__) 222 223 /* -------------------------------------------------------------------------- 224 * Device Flags 225 * -------------------------------------------------------------------------- */ 226 227 static bool acpi_ec_started(struct acpi_ec *ec) 228 { 229 return test_bit(EC_FLAGS_STARTED, &ec->flags) && 230 !test_bit(EC_FLAGS_STOPPED, &ec->flags); 231 } 232 233 static bool acpi_ec_flushed(struct acpi_ec *ec) 234 { 235 return ec->reference_count == 1; 236 } 237 238 /* -------------------------------------------------------------------------- 239 * EC Registers 240 * -------------------------------------------------------------------------- */ 241 242 static inline u8 acpi_ec_read_status(struct acpi_ec *ec) 243 { 244 u8 x = inb(ec->command_addr); 245 246 ec_dbg_raw("EC_SC(R) = 0x%2.2x " 247 "SCI_EVT=%d BURST=%d CMD=%d IBF=%d OBF=%d", 248 x, 249 !!(x & ACPI_EC_FLAG_SCI), 250 !!(x & ACPI_EC_FLAG_BURST), 251 !!(x & ACPI_EC_FLAG_CMD), 252 !!(x & ACPI_EC_FLAG_IBF), 253 !!(x & ACPI_EC_FLAG_OBF)); 254 return x; 255 } 256 257 static inline u8 acpi_ec_read_data(struct acpi_ec *ec) 258 { 259 u8 x = inb(ec->data_addr); 260 261 ec->timestamp = jiffies; 262 ec_dbg_raw("EC_DATA(R) = 0x%2.2x", x); 263 return x; 264 } 265 266 static inline void acpi_ec_write_cmd(struct acpi_ec *ec, u8 command) 267 { 268 ec_dbg_raw("EC_SC(W) = 0x%2.2x", command); 269 outb(command, ec->command_addr); 270 ec->timestamp = jiffies; 271 } 272 273 static inline void acpi_ec_write_data(struct acpi_ec *ec, u8 data) 274 { 275 ec_dbg_raw("EC_DATA(W) = 0x%2.2x", data); 276 outb(data, ec->data_addr); 277 ec->timestamp = jiffies; 278 } 279 280 #ifdef DEBUG 281 static const char *acpi_ec_cmd_string(u8 cmd) 282 { 283 switch (cmd) { 284 case 0x80: 285 return "RD_EC"; 286 case 0x81: 287 return "WR_EC"; 288 case 0x82: 289 return "BE_EC"; 290 case 0x83: 291 return "BD_EC"; 292 case 0x84: 293 return "QR_EC"; 294 } 295 return "UNKNOWN"; 296 } 297 #else 298 #define acpi_ec_cmd_string(cmd) "UNDEF" 299 #endif 300 301 /* -------------------------------------------------------------------------- 302 * GPE Registers 303 * -------------------------------------------------------------------------- */ 304 305 static inline bool acpi_ec_is_gpe_raised(struct acpi_ec *ec) 306 { 307 acpi_event_status gpe_status = 0; 308 309 (void)acpi_get_gpe_status(NULL, ec->gpe, &gpe_status); 310 return (gpe_status & ACPI_EVENT_FLAG_STATUS_SET) ? true : false; 311 } 312 313 static inline void acpi_ec_enable_gpe(struct acpi_ec *ec, bool open) 314 { 315 if (open) 316 acpi_enable_gpe(NULL, ec->gpe); 317 else { 318 BUG_ON(ec->reference_count < 1); 319 acpi_set_gpe(NULL, ec->gpe, ACPI_GPE_ENABLE); 320 } 321 if (acpi_ec_is_gpe_raised(ec)) { 322 /* 323 * On some platforms, EN=1 writes cannot trigger GPE. So 324 * software need to manually trigger a pseudo GPE event on 325 * EN=1 writes. 326 */ 327 ec_dbg_raw("Polling quirk"); 328 advance_transaction(ec); 329 } 330 } 331 332 static inline void acpi_ec_disable_gpe(struct acpi_ec *ec, bool close) 333 { 334 if (close) 335 acpi_disable_gpe(NULL, ec->gpe); 336 else { 337 BUG_ON(ec->reference_count < 1); 338 acpi_set_gpe(NULL, ec->gpe, ACPI_GPE_DISABLE); 339 } 340 } 341 342 static inline void acpi_ec_clear_gpe(struct acpi_ec *ec) 343 { 344 /* 345 * GPE STS is a W1C register, which means: 346 * 1. Software can clear it without worrying about clearing other 347 * GPEs' STS bits when the hardware sets them in parallel. 348 * 2. As long as software can ensure only clearing it when it is 349 * set, hardware won't set it in parallel. 350 * So software can clear GPE in any contexts. 351 * Warning: do not move the check into advance_transaction() as the 352 * EC commands will be sent without GPE raised. 353 */ 354 if (!acpi_ec_is_gpe_raised(ec)) 355 return; 356 acpi_clear_gpe(NULL, ec->gpe); 357 } 358 359 /* -------------------------------------------------------------------------- 360 * Transaction Management 361 * -------------------------------------------------------------------------- */ 362 363 static void acpi_ec_submit_request(struct acpi_ec *ec) 364 { 365 ec->reference_count++; 366 if (ec->reference_count == 1) 367 acpi_ec_enable_gpe(ec, true); 368 } 369 370 static void acpi_ec_complete_request(struct acpi_ec *ec) 371 { 372 bool flushed = false; 373 374 ec->reference_count--; 375 if (ec->reference_count == 0) 376 acpi_ec_disable_gpe(ec, true); 377 flushed = acpi_ec_flushed(ec); 378 if (flushed) 379 wake_up(&ec->wait); 380 } 381 382 static void acpi_ec_set_storm(struct acpi_ec *ec, u8 flag) 383 { 384 if (!test_bit(flag, &ec->flags)) { 385 acpi_ec_disable_gpe(ec, false); 386 ec_dbg_drv("Polling enabled"); 387 set_bit(flag, &ec->flags); 388 } 389 } 390 391 static void acpi_ec_clear_storm(struct acpi_ec *ec, u8 flag) 392 { 393 if (test_bit(flag, &ec->flags)) { 394 clear_bit(flag, &ec->flags); 395 acpi_ec_enable_gpe(ec, false); 396 ec_dbg_drv("Polling disabled"); 397 } 398 } 399 400 /* 401 * acpi_ec_submit_flushable_request() - Increase the reference count unless 402 * the flush operation is not in 403 * progress 404 * @ec: the EC device 405 * 406 * This function must be used before taking a new action that should hold 407 * the reference count. If this function returns false, then the action 408 * must be discarded or it will prevent the flush operation from being 409 * completed. 410 */ 411 static bool acpi_ec_submit_flushable_request(struct acpi_ec *ec) 412 { 413 if (!acpi_ec_started(ec)) 414 return false; 415 acpi_ec_submit_request(ec); 416 return true; 417 } 418 419 static void acpi_ec_submit_query(struct acpi_ec *ec) 420 { 421 if (!test_and_set_bit(EC_FLAGS_QUERY_PENDING, &ec->flags)) { 422 ec_dbg_evt("Command(%s) submitted/blocked", 423 acpi_ec_cmd_string(ACPI_EC_COMMAND_QUERY)); 424 ec->nr_pending_queries++; 425 schedule_work(&ec->work); 426 } 427 } 428 429 static void acpi_ec_complete_query(struct acpi_ec *ec) 430 { 431 if (test_bit(EC_FLAGS_QUERY_PENDING, &ec->flags)) { 432 clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags); 433 ec_dbg_evt("Command(%s) unblocked", 434 acpi_ec_cmd_string(ACPI_EC_COMMAND_QUERY)); 435 } 436 } 437 438 static bool acpi_ec_guard_event(struct acpi_ec *ec) 439 { 440 if (ec_event_clearing == ACPI_EC_EVT_TIMING_STATUS || 441 ec_event_clearing == ACPI_EC_EVT_TIMING_QUERY || 442 !test_bit(EC_FLAGS_QUERY_PENDING, &ec->flags) || 443 (ec->curr && ec->curr->command == ACPI_EC_COMMAND_QUERY)) 444 return false; 445 446 /* 447 * Postpone the query submission to allow the firmware to proceed, 448 * we shouldn't check SCI_EVT before the firmware reflagging it. 449 */ 450 return true; 451 } 452 453 static int ec_transaction_polled(struct acpi_ec *ec) 454 { 455 unsigned long flags; 456 int ret = 0; 457 458 spin_lock_irqsave(&ec->lock, flags); 459 if (ec->curr && (ec->curr->flags & ACPI_EC_COMMAND_POLL)) 460 ret = 1; 461 spin_unlock_irqrestore(&ec->lock, flags); 462 return ret; 463 } 464 465 static int ec_transaction_completed(struct acpi_ec *ec) 466 { 467 unsigned long flags; 468 int ret = 0; 469 470 spin_lock_irqsave(&ec->lock, flags); 471 if (ec->curr && (ec->curr->flags & ACPI_EC_COMMAND_COMPLETE)) 472 ret = 1; 473 spin_unlock_irqrestore(&ec->lock, flags); 474 return ret; 475 } 476 477 static inline void ec_transaction_transition(struct acpi_ec *ec, unsigned long flag) 478 { 479 ec->curr->flags |= flag; 480 if (ec->curr->command == ACPI_EC_COMMAND_QUERY) { 481 if (ec_event_clearing == ACPI_EC_EVT_TIMING_STATUS && 482 flag == ACPI_EC_COMMAND_POLL) 483 acpi_ec_complete_query(ec); 484 if (ec_event_clearing == ACPI_EC_EVT_TIMING_QUERY && 485 flag == ACPI_EC_COMMAND_COMPLETE) 486 acpi_ec_complete_query(ec); 487 if (ec_event_clearing == ACPI_EC_EVT_TIMING_EVENT && 488 flag == ACPI_EC_COMMAND_COMPLETE) 489 set_bit(EC_FLAGS_QUERY_GUARDING, &ec->flags); 490 } 491 } 492 493 static void advance_transaction(struct acpi_ec *ec) 494 { 495 struct transaction *t; 496 u8 status; 497 bool wakeup = false; 498 499 ec_dbg_stm("%s (%d)", in_interrupt() ? "IRQ" : "TASK", 500 smp_processor_id()); 501 /* 502 * By always clearing STS before handling all indications, we can 503 * ensure a hardware STS 0->1 change after this clearing can always 504 * trigger a GPE interrupt. 505 */ 506 acpi_ec_clear_gpe(ec); 507 status = acpi_ec_read_status(ec); 508 t = ec->curr; 509 /* 510 * Another IRQ or a guarded polling mode advancement is detected, 511 * the next QR_EC submission is then allowed. 512 */ 513 if (!t || !(t->flags & ACPI_EC_COMMAND_POLL)) { 514 if (ec_event_clearing == ACPI_EC_EVT_TIMING_EVENT && 515 (!ec->nr_pending_queries || 516 test_bit(EC_FLAGS_QUERY_GUARDING, &ec->flags))) { 517 clear_bit(EC_FLAGS_QUERY_GUARDING, &ec->flags); 518 acpi_ec_complete_query(ec); 519 } 520 } 521 if (!t) 522 goto err; 523 if (t->flags & ACPI_EC_COMMAND_POLL) { 524 if (t->wlen > t->wi) { 525 if ((status & ACPI_EC_FLAG_IBF) == 0) 526 acpi_ec_write_data(ec, t->wdata[t->wi++]); 527 else 528 goto err; 529 } else if (t->rlen > t->ri) { 530 if ((status & ACPI_EC_FLAG_OBF) == 1) { 531 t->rdata[t->ri++] = acpi_ec_read_data(ec); 532 if (t->rlen == t->ri) { 533 ec_transaction_transition(ec, ACPI_EC_COMMAND_COMPLETE); 534 if (t->command == ACPI_EC_COMMAND_QUERY) 535 ec_dbg_evt("Command(%s) completed by hardware", 536 acpi_ec_cmd_string(ACPI_EC_COMMAND_QUERY)); 537 wakeup = true; 538 } 539 } else 540 goto err; 541 } else if (t->wlen == t->wi && 542 (status & ACPI_EC_FLAG_IBF) == 0) { 543 ec_transaction_transition(ec, ACPI_EC_COMMAND_COMPLETE); 544 wakeup = true; 545 } 546 goto out; 547 } else { 548 if (EC_FLAGS_QUERY_HANDSHAKE && 549 !(status & ACPI_EC_FLAG_SCI) && 550 (t->command == ACPI_EC_COMMAND_QUERY)) { 551 ec_transaction_transition(ec, ACPI_EC_COMMAND_POLL); 552 t->rdata[t->ri++] = 0x00; 553 ec_transaction_transition(ec, ACPI_EC_COMMAND_COMPLETE); 554 ec_dbg_evt("Command(%s) completed by software", 555 acpi_ec_cmd_string(ACPI_EC_COMMAND_QUERY)); 556 wakeup = true; 557 } else if ((status & ACPI_EC_FLAG_IBF) == 0) { 558 acpi_ec_write_cmd(ec, t->command); 559 ec_transaction_transition(ec, ACPI_EC_COMMAND_POLL); 560 } else 561 goto err; 562 goto out; 563 } 564 err: 565 /* 566 * If SCI bit is set, then don't think it's a false IRQ 567 * otherwise will take a not handled IRQ as a false one. 568 */ 569 if (!(status & ACPI_EC_FLAG_SCI)) { 570 if (in_interrupt() && t) { 571 if (t->irq_count < ec_storm_threshold) 572 ++t->irq_count; 573 /* Allow triggering on 0 threshold */ 574 if (t->irq_count == ec_storm_threshold) 575 acpi_ec_set_storm(ec, EC_FLAGS_COMMAND_STORM); 576 } 577 } 578 out: 579 if (status & ACPI_EC_FLAG_SCI) 580 acpi_ec_submit_query(ec); 581 if (wakeup && in_interrupt()) 582 wake_up(&ec->wait); 583 } 584 585 static void start_transaction(struct acpi_ec *ec) 586 { 587 ec->curr->irq_count = ec->curr->wi = ec->curr->ri = 0; 588 ec->curr->flags = 0; 589 } 590 591 static int ec_guard(struct acpi_ec *ec) 592 { 593 unsigned long guard = usecs_to_jiffies(ec_polling_guard); 594 unsigned long timeout = ec->timestamp + guard; 595 596 do { 597 if (ec_busy_polling) { 598 /* Perform busy polling */ 599 if (ec_transaction_completed(ec)) 600 return 0; 601 udelay(jiffies_to_usecs(guard)); 602 } else { 603 /* 604 * Perform wait polling 605 * 606 * For SCI_EVT clearing timing of "event", 607 * performing guarding before re-checking the 608 * SCI_EVT. Otherwise, such guarding is not needed 609 * due to the old practices. 610 */ 611 if (!ec_transaction_polled(ec) && 612 !acpi_ec_guard_event(ec)) 613 break; 614 if (wait_event_timeout(ec->wait, 615 ec_transaction_completed(ec), 616 guard)) 617 return 0; 618 } 619 /* Guard the register accesses for the polling modes */ 620 } while (time_before(jiffies, timeout)); 621 return -ETIME; 622 } 623 624 static int ec_poll(struct acpi_ec *ec) 625 { 626 unsigned long flags; 627 int repeat = 5; /* number of command restarts */ 628 629 while (repeat--) { 630 unsigned long delay = jiffies + 631 msecs_to_jiffies(ec_delay); 632 do { 633 if (!ec_guard(ec)) 634 return 0; 635 spin_lock_irqsave(&ec->lock, flags); 636 advance_transaction(ec); 637 spin_unlock_irqrestore(&ec->lock, flags); 638 } while (time_before(jiffies, delay)); 639 pr_debug("controller reset, restart transaction\n"); 640 spin_lock_irqsave(&ec->lock, flags); 641 start_transaction(ec); 642 spin_unlock_irqrestore(&ec->lock, flags); 643 } 644 return -ETIME; 645 } 646 647 static int acpi_ec_transaction_unlocked(struct acpi_ec *ec, 648 struct transaction *t) 649 { 650 unsigned long tmp; 651 int ret = 0; 652 653 /* start transaction */ 654 spin_lock_irqsave(&ec->lock, tmp); 655 /* Enable GPE for command processing (IBF=0/OBF=1) */ 656 if (!acpi_ec_submit_flushable_request(ec)) { 657 ret = -EINVAL; 658 goto unlock; 659 } 660 ec_dbg_ref(ec, "Increase command"); 661 /* following two actions should be kept atomic */ 662 ec->curr = t; 663 ec_dbg_req("Command(%s) started", acpi_ec_cmd_string(t->command)); 664 start_transaction(ec); 665 spin_unlock_irqrestore(&ec->lock, tmp); 666 667 ret = ec_poll(ec); 668 669 spin_lock_irqsave(&ec->lock, tmp); 670 if (t->irq_count == ec_storm_threshold) 671 acpi_ec_clear_storm(ec, EC_FLAGS_COMMAND_STORM); 672 ec_dbg_req("Command(%s) stopped", acpi_ec_cmd_string(t->command)); 673 ec->curr = NULL; 674 /* Disable GPE for command processing (IBF=0/OBF=1) */ 675 acpi_ec_complete_request(ec); 676 ec_dbg_ref(ec, "Decrease command"); 677 unlock: 678 spin_unlock_irqrestore(&ec->lock, tmp); 679 return ret; 680 } 681 682 static int acpi_ec_transaction(struct acpi_ec *ec, struct transaction *t) 683 { 684 int status; 685 u32 glk; 686 687 if (!ec || (!t) || (t->wlen && !t->wdata) || (t->rlen && !t->rdata)) 688 return -EINVAL; 689 if (t->rdata) 690 memset(t->rdata, 0, t->rlen); 691 692 mutex_lock(&ec->mutex); 693 if (ec->global_lock) { 694 status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk); 695 if (ACPI_FAILURE(status)) { 696 status = -ENODEV; 697 goto unlock; 698 } 699 } 700 701 status = acpi_ec_transaction_unlocked(ec, t); 702 703 if (ec->global_lock) 704 acpi_release_global_lock(glk); 705 unlock: 706 mutex_unlock(&ec->mutex); 707 return status; 708 } 709 710 static int acpi_ec_burst_enable(struct acpi_ec *ec) 711 { 712 u8 d; 713 struct transaction t = {.command = ACPI_EC_BURST_ENABLE, 714 .wdata = NULL, .rdata = &d, 715 .wlen = 0, .rlen = 1}; 716 717 return acpi_ec_transaction(ec, &t); 718 } 719 720 static int acpi_ec_burst_disable(struct acpi_ec *ec) 721 { 722 struct transaction t = {.command = ACPI_EC_BURST_DISABLE, 723 .wdata = NULL, .rdata = NULL, 724 .wlen = 0, .rlen = 0}; 725 726 return (acpi_ec_read_status(ec) & ACPI_EC_FLAG_BURST) ? 727 acpi_ec_transaction(ec, &t) : 0; 728 } 729 730 static int acpi_ec_read(struct acpi_ec *ec, u8 address, u8 *data) 731 { 732 int result; 733 u8 d; 734 struct transaction t = {.command = ACPI_EC_COMMAND_READ, 735 .wdata = &address, .rdata = &d, 736 .wlen = 1, .rlen = 1}; 737 738 result = acpi_ec_transaction(ec, &t); 739 *data = d; 740 return result; 741 } 742 743 static int acpi_ec_write(struct acpi_ec *ec, u8 address, u8 data) 744 { 745 u8 wdata[2] = { address, data }; 746 struct transaction t = {.command = ACPI_EC_COMMAND_WRITE, 747 .wdata = wdata, .rdata = NULL, 748 .wlen = 2, .rlen = 0}; 749 750 return acpi_ec_transaction(ec, &t); 751 } 752 753 int ec_read(u8 addr, u8 *val) 754 { 755 int err; 756 u8 temp_data; 757 758 if (!first_ec) 759 return -ENODEV; 760 761 err = acpi_ec_read(first_ec, addr, &temp_data); 762 763 if (!err) { 764 *val = temp_data; 765 return 0; 766 } 767 return err; 768 } 769 EXPORT_SYMBOL(ec_read); 770 771 int ec_write(u8 addr, u8 val) 772 { 773 int err; 774 775 if (!first_ec) 776 return -ENODEV; 777 778 err = acpi_ec_write(first_ec, addr, val); 779 780 return err; 781 } 782 EXPORT_SYMBOL(ec_write); 783 784 int ec_transaction(u8 command, 785 const u8 *wdata, unsigned wdata_len, 786 u8 *rdata, unsigned rdata_len) 787 { 788 struct transaction t = {.command = command, 789 .wdata = wdata, .rdata = rdata, 790 .wlen = wdata_len, .rlen = rdata_len}; 791 792 if (!first_ec) 793 return -ENODEV; 794 795 return acpi_ec_transaction(first_ec, &t); 796 } 797 EXPORT_SYMBOL(ec_transaction); 798 799 /* Get the handle to the EC device */ 800 acpi_handle ec_get_handle(void) 801 { 802 if (!first_ec) 803 return NULL; 804 return first_ec->handle; 805 } 806 EXPORT_SYMBOL(ec_get_handle); 807 808 /* 809 * Process _Q events that might have accumulated in the EC. 810 * Run with locked ec mutex. 811 */ 812 static void acpi_ec_clear(struct acpi_ec *ec) 813 { 814 int i, status; 815 u8 value = 0; 816 817 for (i = 0; i < ACPI_EC_CLEAR_MAX; i++) { 818 status = acpi_ec_query(ec, &value); 819 if (status || !value) 820 break; 821 } 822 823 if (unlikely(i == ACPI_EC_CLEAR_MAX)) 824 pr_warn("Warning: Maximum of %d stale EC events cleared\n", i); 825 else 826 pr_info("%d stale EC events cleared\n", i); 827 } 828 829 static void acpi_ec_start(struct acpi_ec *ec, bool resuming) 830 { 831 unsigned long flags; 832 833 spin_lock_irqsave(&ec->lock, flags); 834 if (!test_and_set_bit(EC_FLAGS_STARTED, &ec->flags)) { 835 ec_dbg_drv("Starting EC"); 836 /* Enable GPE for event processing (SCI_EVT=1) */ 837 if (!resuming) { 838 acpi_ec_submit_request(ec); 839 ec_dbg_ref(ec, "Increase driver"); 840 } 841 ec_log_drv("EC started"); 842 } 843 spin_unlock_irqrestore(&ec->lock, flags); 844 } 845 846 static bool acpi_ec_stopped(struct acpi_ec *ec) 847 { 848 unsigned long flags; 849 bool flushed; 850 851 spin_lock_irqsave(&ec->lock, flags); 852 flushed = acpi_ec_flushed(ec); 853 spin_unlock_irqrestore(&ec->lock, flags); 854 return flushed; 855 } 856 857 static void acpi_ec_stop(struct acpi_ec *ec, bool suspending) 858 { 859 unsigned long flags; 860 861 spin_lock_irqsave(&ec->lock, flags); 862 if (acpi_ec_started(ec)) { 863 ec_dbg_drv("Stopping EC"); 864 set_bit(EC_FLAGS_STOPPED, &ec->flags); 865 spin_unlock_irqrestore(&ec->lock, flags); 866 wait_event(ec->wait, acpi_ec_stopped(ec)); 867 spin_lock_irqsave(&ec->lock, flags); 868 /* Disable GPE for event processing (SCI_EVT=1) */ 869 if (!suspending) { 870 acpi_ec_complete_request(ec); 871 ec_dbg_ref(ec, "Decrease driver"); 872 } 873 clear_bit(EC_FLAGS_STARTED, &ec->flags); 874 clear_bit(EC_FLAGS_STOPPED, &ec->flags); 875 ec_log_drv("EC stopped"); 876 } 877 spin_unlock_irqrestore(&ec->lock, flags); 878 } 879 880 void acpi_ec_block_transactions(void) 881 { 882 struct acpi_ec *ec = first_ec; 883 884 if (!ec) 885 return; 886 887 mutex_lock(&ec->mutex); 888 /* Prevent transactions from being carried out */ 889 acpi_ec_stop(ec, true); 890 mutex_unlock(&ec->mutex); 891 } 892 893 void acpi_ec_unblock_transactions(void) 894 { 895 struct acpi_ec *ec = first_ec; 896 897 if (!ec) 898 return; 899 900 /* Allow transactions to be carried out again */ 901 acpi_ec_start(ec, true); 902 903 if (EC_FLAGS_CLEAR_ON_RESUME) 904 acpi_ec_clear(ec); 905 } 906 907 void acpi_ec_unblock_transactions_early(void) 908 { 909 /* 910 * Allow transactions to happen again (this function is called from 911 * atomic context during wakeup, so we don't need to acquire the mutex). 912 */ 913 if (first_ec) 914 acpi_ec_start(first_ec, true); 915 } 916 917 /* -------------------------------------------------------------------------- 918 Event Management 919 -------------------------------------------------------------------------- */ 920 static struct acpi_ec_query_handler * 921 acpi_ec_get_query_handler(struct acpi_ec_query_handler *handler) 922 { 923 if (handler) 924 kref_get(&handler->kref); 925 return handler; 926 } 927 928 static void acpi_ec_query_handler_release(struct kref *kref) 929 { 930 struct acpi_ec_query_handler *handler = 931 container_of(kref, struct acpi_ec_query_handler, kref); 932 933 kfree(handler); 934 } 935 936 static void acpi_ec_put_query_handler(struct acpi_ec_query_handler *handler) 937 { 938 kref_put(&handler->kref, acpi_ec_query_handler_release); 939 } 940 941 int acpi_ec_add_query_handler(struct acpi_ec *ec, u8 query_bit, 942 acpi_handle handle, acpi_ec_query_func func, 943 void *data) 944 { 945 struct acpi_ec_query_handler *handler = 946 kzalloc(sizeof(struct acpi_ec_query_handler), GFP_KERNEL); 947 948 if (!handler) 949 return -ENOMEM; 950 951 handler->query_bit = query_bit; 952 handler->handle = handle; 953 handler->func = func; 954 handler->data = data; 955 mutex_lock(&ec->mutex); 956 kref_init(&handler->kref); 957 list_add(&handler->node, &ec->list); 958 mutex_unlock(&ec->mutex); 959 return 0; 960 } 961 EXPORT_SYMBOL_GPL(acpi_ec_add_query_handler); 962 963 void acpi_ec_remove_query_handler(struct acpi_ec *ec, u8 query_bit) 964 { 965 struct acpi_ec_query_handler *handler, *tmp; 966 LIST_HEAD(free_list); 967 968 mutex_lock(&ec->mutex); 969 list_for_each_entry_safe(handler, tmp, &ec->list, node) { 970 if (query_bit == handler->query_bit) { 971 list_del_init(&handler->node); 972 list_add(&handler->node, &free_list); 973 } 974 } 975 mutex_unlock(&ec->mutex); 976 list_for_each_entry_safe(handler, tmp, &free_list, node) 977 acpi_ec_put_query_handler(handler); 978 } 979 EXPORT_SYMBOL_GPL(acpi_ec_remove_query_handler); 980 981 static void acpi_ec_run(void *cxt) 982 { 983 struct acpi_ec_query_handler *handler = cxt; 984 985 if (!handler) 986 return; 987 ec_dbg_evt("Query(0x%02x) started", handler->query_bit); 988 if (handler->func) 989 handler->func(handler->data); 990 else if (handler->handle) 991 acpi_evaluate_object(handler->handle, NULL, NULL, NULL); 992 ec_dbg_evt("Query(0x%02x) stopped", handler->query_bit); 993 acpi_ec_put_query_handler(handler); 994 } 995 996 static int acpi_ec_query(struct acpi_ec *ec, u8 *data) 997 { 998 u8 value = 0; 999 int result; 1000 acpi_status status; 1001 struct acpi_ec_query_handler *handler; 1002 struct transaction t = {.command = ACPI_EC_COMMAND_QUERY, 1003 .wdata = NULL, .rdata = &value, 1004 .wlen = 0, .rlen = 1}; 1005 1006 /* 1007 * Query the EC to find out which _Qxx method we need to evaluate. 1008 * Note that successful completion of the query causes the ACPI_EC_SCI 1009 * bit to be cleared (and thus clearing the interrupt source). 1010 */ 1011 result = acpi_ec_transaction(ec, &t); 1012 if (result) 1013 return result; 1014 if (data) 1015 *data = value; 1016 if (!value) 1017 return -ENODATA; 1018 1019 mutex_lock(&ec->mutex); 1020 list_for_each_entry(handler, &ec->list, node) { 1021 if (value == handler->query_bit) { 1022 /* have custom handler for this bit */ 1023 handler = acpi_ec_get_query_handler(handler); 1024 ec_dbg_evt("Query(0x%02x) scheduled", 1025 handler->query_bit); 1026 status = acpi_os_execute((handler->func) ? 1027 OSL_NOTIFY_HANDLER : OSL_GPE_HANDLER, 1028 acpi_ec_run, handler); 1029 if (ACPI_FAILURE(status)) 1030 result = -EBUSY; 1031 break; 1032 } 1033 } 1034 mutex_unlock(&ec->mutex); 1035 return result; 1036 } 1037 1038 static void acpi_ec_check_event(struct acpi_ec *ec) 1039 { 1040 unsigned long flags; 1041 1042 if (ec_event_clearing == ACPI_EC_EVT_TIMING_EVENT) { 1043 if (ec_guard(ec)) { 1044 spin_lock_irqsave(&ec->lock, flags); 1045 /* 1046 * Take care of the SCI_EVT unless no one else is 1047 * taking care of it. 1048 */ 1049 if (!ec->curr) 1050 advance_transaction(ec); 1051 spin_unlock_irqrestore(&ec->lock, flags); 1052 } 1053 } 1054 } 1055 1056 static void acpi_ec_event_handler(struct work_struct *work) 1057 { 1058 unsigned long flags; 1059 struct acpi_ec *ec = container_of(work, struct acpi_ec, work); 1060 1061 ec_dbg_evt("Event started"); 1062 1063 spin_lock_irqsave(&ec->lock, flags); 1064 while (ec->nr_pending_queries) { 1065 spin_unlock_irqrestore(&ec->lock, flags); 1066 (void)acpi_ec_query(ec, NULL); 1067 spin_lock_irqsave(&ec->lock, flags); 1068 ec->nr_pending_queries--; 1069 /* 1070 * Before exit, make sure that this work item can be 1071 * scheduled again. There might be QR_EC failures, leaving 1072 * EC_FLAGS_QUERY_PENDING uncleared and preventing this work 1073 * item from being scheduled again. 1074 */ 1075 if (!ec->nr_pending_queries) { 1076 if (ec_event_clearing == ACPI_EC_EVT_TIMING_STATUS || 1077 ec_event_clearing == ACPI_EC_EVT_TIMING_QUERY) 1078 acpi_ec_complete_query(ec); 1079 } 1080 } 1081 spin_unlock_irqrestore(&ec->lock, flags); 1082 1083 ec_dbg_evt("Event stopped"); 1084 1085 acpi_ec_check_event(ec); 1086 } 1087 1088 static u32 acpi_ec_gpe_handler(acpi_handle gpe_device, 1089 u32 gpe_number, void *data) 1090 { 1091 unsigned long flags; 1092 struct acpi_ec *ec = data; 1093 1094 spin_lock_irqsave(&ec->lock, flags); 1095 advance_transaction(ec); 1096 spin_unlock_irqrestore(&ec->lock, flags); 1097 return ACPI_INTERRUPT_HANDLED; 1098 } 1099 1100 /* -------------------------------------------------------------------------- 1101 * Address Space Management 1102 * -------------------------------------------------------------------------- */ 1103 1104 static acpi_status 1105 acpi_ec_space_handler(u32 function, acpi_physical_address address, 1106 u32 bits, u64 *value64, 1107 void *handler_context, void *region_context) 1108 { 1109 struct acpi_ec *ec = handler_context; 1110 int result = 0, i, bytes = bits / 8; 1111 u8 *value = (u8 *)value64; 1112 1113 if ((address > 0xFF) || !value || !handler_context) 1114 return AE_BAD_PARAMETER; 1115 1116 if (function != ACPI_READ && function != ACPI_WRITE) 1117 return AE_BAD_PARAMETER; 1118 1119 if (ec_busy_polling || bits > 8) 1120 acpi_ec_burst_enable(ec); 1121 1122 for (i = 0; i < bytes; ++i, ++address, ++value) 1123 result = (function == ACPI_READ) ? 1124 acpi_ec_read(ec, address, value) : 1125 acpi_ec_write(ec, address, *value); 1126 1127 if (ec_busy_polling || bits > 8) 1128 acpi_ec_burst_disable(ec); 1129 1130 switch (result) { 1131 case -EINVAL: 1132 return AE_BAD_PARAMETER; 1133 case -ENODEV: 1134 return AE_NOT_FOUND; 1135 case -ETIME: 1136 return AE_TIME; 1137 default: 1138 return AE_OK; 1139 } 1140 } 1141 1142 /* -------------------------------------------------------------------------- 1143 * Driver Interface 1144 * -------------------------------------------------------------------------- */ 1145 1146 static acpi_status 1147 ec_parse_io_ports(struct acpi_resource *resource, void *context); 1148 1149 static struct acpi_ec *make_acpi_ec(void) 1150 { 1151 struct acpi_ec *ec = kzalloc(sizeof(struct acpi_ec), GFP_KERNEL); 1152 1153 if (!ec) 1154 return NULL; 1155 ec->flags = 1 << EC_FLAGS_QUERY_PENDING; 1156 mutex_init(&ec->mutex); 1157 init_waitqueue_head(&ec->wait); 1158 INIT_LIST_HEAD(&ec->list); 1159 spin_lock_init(&ec->lock); 1160 INIT_WORK(&ec->work, acpi_ec_event_handler); 1161 ec->timestamp = jiffies; 1162 return ec; 1163 } 1164 1165 static acpi_status 1166 acpi_ec_register_query_methods(acpi_handle handle, u32 level, 1167 void *context, void **return_value) 1168 { 1169 char node_name[5]; 1170 struct acpi_buffer buffer = { sizeof(node_name), node_name }; 1171 struct acpi_ec *ec = context; 1172 int value = 0; 1173 acpi_status status; 1174 1175 status = acpi_get_name(handle, ACPI_SINGLE_NAME, &buffer); 1176 1177 if (ACPI_SUCCESS(status) && sscanf(node_name, "_Q%x", &value) == 1) 1178 acpi_ec_add_query_handler(ec, value, handle, NULL, NULL); 1179 return AE_OK; 1180 } 1181 1182 static acpi_status 1183 ec_parse_device(acpi_handle handle, u32 Level, void *context, void **retval) 1184 { 1185 acpi_status status; 1186 unsigned long long tmp = 0; 1187 struct acpi_ec *ec = context; 1188 1189 /* clear addr values, ec_parse_io_ports depend on it */ 1190 ec->command_addr = ec->data_addr = 0; 1191 1192 status = acpi_walk_resources(handle, METHOD_NAME__CRS, 1193 ec_parse_io_ports, ec); 1194 if (ACPI_FAILURE(status)) 1195 return status; 1196 1197 /* Get GPE bit assignment (EC events). */ 1198 /* TODO: Add support for _GPE returning a package */ 1199 status = acpi_evaluate_integer(handle, "_GPE", NULL, &tmp); 1200 if (ACPI_FAILURE(status)) 1201 return status; 1202 ec->gpe = tmp; 1203 /* Use the global lock for all EC transactions? */ 1204 tmp = 0; 1205 acpi_evaluate_integer(handle, "_GLK", NULL, &tmp); 1206 ec->global_lock = tmp; 1207 ec->handle = handle; 1208 return AE_CTRL_TERMINATE; 1209 } 1210 1211 static int ec_install_handlers(struct acpi_ec *ec) 1212 { 1213 acpi_status status; 1214 1215 if (test_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags)) 1216 return 0; 1217 status = acpi_install_gpe_raw_handler(NULL, ec->gpe, 1218 ACPI_GPE_EDGE_TRIGGERED, 1219 &acpi_ec_gpe_handler, ec); 1220 if (ACPI_FAILURE(status)) 1221 return -ENODEV; 1222 1223 acpi_ec_start(ec, false); 1224 status = acpi_install_address_space_handler(ec->handle, 1225 ACPI_ADR_SPACE_EC, 1226 &acpi_ec_space_handler, 1227 NULL, ec); 1228 if (ACPI_FAILURE(status)) { 1229 if (status == AE_NOT_FOUND) { 1230 /* 1231 * Maybe OS fails in evaluating the _REG object. 1232 * The AE_NOT_FOUND error will be ignored and OS 1233 * continue to initialize EC. 1234 */ 1235 pr_err("Fail in evaluating the _REG object" 1236 " of EC device. Broken bios is suspected.\n"); 1237 } else { 1238 acpi_ec_stop(ec, false); 1239 acpi_remove_gpe_handler(NULL, ec->gpe, 1240 &acpi_ec_gpe_handler); 1241 return -ENODEV; 1242 } 1243 } 1244 1245 set_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags); 1246 return 0; 1247 } 1248 1249 static void ec_remove_handlers(struct acpi_ec *ec) 1250 { 1251 if (!test_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags)) 1252 return; 1253 acpi_ec_stop(ec, false); 1254 if (ACPI_FAILURE(acpi_remove_address_space_handler(ec->handle, 1255 ACPI_ADR_SPACE_EC, &acpi_ec_space_handler))) 1256 pr_err("failed to remove space handler\n"); 1257 if (ACPI_FAILURE(acpi_remove_gpe_handler(NULL, ec->gpe, 1258 &acpi_ec_gpe_handler))) 1259 pr_err("failed to remove gpe handler\n"); 1260 clear_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags); 1261 } 1262 1263 static int acpi_ec_add(struct acpi_device *device) 1264 { 1265 struct acpi_ec *ec = NULL; 1266 int ret; 1267 1268 strcpy(acpi_device_name(device), ACPI_EC_DEVICE_NAME); 1269 strcpy(acpi_device_class(device), ACPI_EC_CLASS); 1270 1271 /* Check for boot EC */ 1272 if (boot_ec && 1273 (boot_ec->handle == device->handle || 1274 boot_ec->handle == ACPI_ROOT_OBJECT)) { 1275 ec = boot_ec; 1276 boot_ec = NULL; 1277 } else { 1278 ec = make_acpi_ec(); 1279 if (!ec) 1280 return -ENOMEM; 1281 } 1282 if (ec_parse_device(device->handle, 0, ec, NULL) != 1283 AE_CTRL_TERMINATE) { 1284 kfree(ec); 1285 return -EINVAL; 1286 } 1287 1288 /* Find and register all query methods */ 1289 acpi_walk_namespace(ACPI_TYPE_METHOD, ec->handle, 1, 1290 acpi_ec_register_query_methods, NULL, ec, NULL); 1291 1292 if (!first_ec) 1293 first_ec = ec; 1294 device->driver_data = ec; 1295 1296 ret = !!request_region(ec->data_addr, 1, "EC data"); 1297 WARN(!ret, "Could not request EC data io port 0x%lx", ec->data_addr); 1298 ret = !!request_region(ec->command_addr, 1, "EC cmd"); 1299 WARN(!ret, "Could not request EC cmd io port 0x%lx", ec->command_addr); 1300 1301 pr_info("GPE = 0x%lx, I/O: command/status = 0x%lx, data = 0x%lx\n", 1302 ec->gpe, ec->command_addr, ec->data_addr); 1303 1304 ret = ec_install_handlers(ec); 1305 1306 /* Reprobe devices depending on the EC */ 1307 acpi_walk_dep_device_list(ec->handle); 1308 1309 /* EC is fully operational, allow queries */ 1310 clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags); 1311 1312 /* Clear stale _Q events if hardware might require that */ 1313 if (EC_FLAGS_CLEAR_ON_RESUME) 1314 acpi_ec_clear(ec); 1315 return ret; 1316 } 1317 1318 static int acpi_ec_remove(struct acpi_device *device) 1319 { 1320 struct acpi_ec *ec; 1321 struct acpi_ec_query_handler *handler, *tmp; 1322 1323 if (!device) 1324 return -EINVAL; 1325 1326 ec = acpi_driver_data(device); 1327 ec_remove_handlers(ec); 1328 mutex_lock(&ec->mutex); 1329 list_for_each_entry_safe(handler, tmp, &ec->list, node) { 1330 list_del(&handler->node); 1331 kfree(handler); 1332 } 1333 mutex_unlock(&ec->mutex); 1334 release_region(ec->data_addr, 1); 1335 release_region(ec->command_addr, 1); 1336 device->driver_data = NULL; 1337 if (ec == first_ec) 1338 first_ec = NULL; 1339 kfree(ec); 1340 return 0; 1341 } 1342 1343 static acpi_status 1344 ec_parse_io_ports(struct acpi_resource *resource, void *context) 1345 { 1346 struct acpi_ec *ec = context; 1347 1348 if (resource->type != ACPI_RESOURCE_TYPE_IO) 1349 return AE_OK; 1350 1351 /* 1352 * The first address region returned is the data port, and 1353 * the second address region returned is the status/command 1354 * port. 1355 */ 1356 if (ec->data_addr == 0) 1357 ec->data_addr = resource->data.io.minimum; 1358 else if (ec->command_addr == 0) 1359 ec->command_addr = resource->data.io.minimum; 1360 else 1361 return AE_CTRL_TERMINATE; 1362 1363 return AE_OK; 1364 } 1365 1366 int __init acpi_boot_ec_enable(void) 1367 { 1368 if (!boot_ec || test_bit(EC_FLAGS_HANDLERS_INSTALLED, &boot_ec->flags)) 1369 return 0; 1370 if (!ec_install_handlers(boot_ec)) { 1371 first_ec = boot_ec; 1372 return 0; 1373 } 1374 return -EFAULT; 1375 } 1376 1377 static const struct acpi_device_id ec_device_ids[] = { 1378 {"PNP0C09", 0}, 1379 {"", 0}, 1380 }; 1381 1382 /* Some BIOS do not survive early DSDT scan, skip it */ 1383 static int ec_skip_dsdt_scan(const struct dmi_system_id *id) 1384 { 1385 EC_FLAGS_SKIP_DSDT_SCAN = 1; 1386 return 0; 1387 } 1388 1389 /* ASUStek often supplies us with broken ECDT, validate it */ 1390 static int ec_validate_ecdt(const struct dmi_system_id *id) 1391 { 1392 EC_FLAGS_VALIDATE_ECDT = 1; 1393 return 0; 1394 } 1395 1396 #if 0 1397 /* 1398 * Some EC firmware variations refuses to respond QR_EC when SCI_EVT is not 1399 * set, for which case, we complete the QR_EC without issuing it to the 1400 * firmware. 1401 * https://bugzilla.kernel.org/show_bug.cgi?id=82611 1402 * https://bugzilla.kernel.org/show_bug.cgi?id=97381 1403 */ 1404 static int ec_flag_query_handshake(const struct dmi_system_id *id) 1405 { 1406 pr_debug("Detected the EC firmware requiring QR_EC issued when SCI_EVT set\n"); 1407 EC_FLAGS_QUERY_HANDSHAKE = 1; 1408 return 0; 1409 } 1410 #endif 1411 1412 /* 1413 * On some hardware it is necessary to clear events accumulated by the EC during 1414 * sleep. These ECs stop reporting GPEs until they are manually polled, if too 1415 * many events are accumulated. (e.g. Samsung Series 5/9 notebooks) 1416 * 1417 * https://bugzilla.kernel.org/show_bug.cgi?id=44161 1418 * 1419 * Ideally, the EC should also be instructed NOT to accumulate events during 1420 * sleep (which Windows seems to do somehow), but the interface to control this 1421 * behaviour is not known at this time. 1422 * 1423 * Models known to be affected are Samsung 530Uxx/535Uxx/540Uxx/550Pxx/900Xxx, 1424 * however it is very likely that other Samsung models are affected. 1425 * 1426 * On systems which don't accumulate _Q events during sleep, this extra check 1427 * should be harmless. 1428 */ 1429 static int ec_clear_on_resume(const struct dmi_system_id *id) 1430 { 1431 pr_debug("Detected system needing EC poll on resume.\n"); 1432 EC_FLAGS_CLEAR_ON_RESUME = 1; 1433 ec_event_clearing = ACPI_EC_EVT_TIMING_STATUS; 1434 return 0; 1435 } 1436 1437 static struct dmi_system_id ec_dmi_table[] __initdata = { 1438 { 1439 ec_skip_dsdt_scan, "Compal JFL92", { 1440 DMI_MATCH(DMI_BIOS_VENDOR, "COMPAL"), 1441 DMI_MATCH(DMI_BOARD_NAME, "JFL92") }, NULL}, 1442 { 1443 ec_validate_ecdt, "MSI MS-171F", { 1444 DMI_MATCH(DMI_SYS_VENDOR, "Micro-Star"), 1445 DMI_MATCH(DMI_PRODUCT_NAME, "MS-171F"),}, NULL}, 1446 { 1447 ec_validate_ecdt, "ASUS hardware", { 1448 DMI_MATCH(DMI_BIOS_VENDOR, "ASUS") }, NULL}, 1449 { 1450 ec_validate_ecdt, "ASUS hardware", { 1451 DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTeK Computer Inc.") }, NULL}, 1452 { 1453 ec_skip_dsdt_scan, "HP Folio 13", { 1454 DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"), 1455 DMI_MATCH(DMI_PRODUCT_NAME, "HP Folio 13"),}, NULL}, 1456 { 1457 ec_validate_ecdt, "ASUS hardware", { 1458 DMI_MATCH(DMI_SYS_VENDOR, "ASUSTek Computer Inc."), 1459 DMI_MATCH(DMI_PRODUCT_NAME, "L4R"),}, NULL}, 1460 { 1461 ec_clear_on_resume, "Samsung hardware", { 1462 DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD.")}, NULL}, 1463 {}, 1464 }; 1465 1466 int __init acpi_ec_ecdt_probe(void) 1467 { 1468 acpi_status status; 1469 struct acpi_ec *saved_ec = NULL; 1470 struct acpi_table_ecdt *ecdt_ptr; 1471 1472 boot_ec = make_acpi_ec(); 1473 if (!boot_ec) 1474 return -ENOMEM; 1475 /* 1476 * Generate a boot ec context 1477 */ 1478 dmi_check_system(ec_dmi_table); 1479 status = acpi_get_table(ACPI_SIG_ECDT, 1, 1480 (struct acpi_table_header **)&ecdt_ptr); 1481 if (ACPI_SUCCESS(status)) { 1482 pr_info("EC description table is found, configuring boot EC\n"); 1483 boot_ec->command_addr = ecdt_ptr->control.address; 1484 boot_ec->data_addr = ecdt_ptr->data.address; 1485 boot_ec->gpe = ecdt_ptr->gpe; 1486 boot_ec->handle = ACPI_ROOT_OBJECT; 1487 acpi_get_handle(ACPI_ROOT_OBJECT, ecdt_ptr->id, 1488 &boot_ec->handle); 1489 /* Don't trust ECDT, which comes from ASUSTek */ 1490 if (!EC_FLAGS_VALIDATE_ECDT) 1491 goto install; 1492 saved_ec = kmemdup(boot_ec, sizeof(struct acpi_ec), GFP_KERNEL); 1493 if (!saved_ec) 1494 return -ENOMEM; 1495 /* fall through */ 1496 } 1497 1498 if (EC_FLAGS_SKIP_DSDT_SCAN) { 1499 kfree(saved_ec); 1500 return -ENODEV; 1501 } 1502 1503 /* This workaround is needed only on some broken machines, 1504 * which require early EC, but fail to provide ECDT */ 1505 pr_debug("Look up EC in DSDT\n"); 1506 status = acpi_get_devices(ec_device_ids[0].id, ec_parse_device, 1507 boot_ec, NULL); 1508 /* Check that acpi_get_devices actually find something */ 1509 if (ACPI_FAILURE(status) || !boot_ec->handle) 1510 goto error; 1511 if (saved_ec) { 1512 /* try to find good ECDT from ASUSTek */ 1513 if (saved_ec->command_addr != boot_ec->command_addr || 1514 saved_ec->data_addr != boot_ec->data_addr || 1515 saved_ec->gpe != boot_ec->gpe || 1516 saved_ec->handle != boot_ec->handle) 1517 pr_info("ASUSTek keeps feeding us with broken " 1518 "ECDT tables, which are very hard to workaround. " 1519 "Trying to use DSDT EC info instead. Please send " 1520 "output of acpidump to linux-acpi@vger.kernel.org\n"); 1521 kfree(saved_ec); 1522 saved_ec = NULL; 1523 } else { 1524 /* We really need to limit this workaround, the only ASUS, 1525 * which needs it, has fake EC._INI method, so use it as flag. 1526 * Keep boot_ec struct as it will be needed soon. 1527 */ 1528 if (!dmi_name_in_vendors("ASUS") || 1529 !acpi_has_method(boot_ec->handle, "_INI")) 1530 return -ENODEV; 1531 } 1532 install: 1533 if (!ec_install_handlers(boot_ec)) { 1534 first_ec = boot_ec; 1535 return 0; 1536 } 1537 error: 1538 kfree(boot_ec); 1539 kfree(saved_ec); 1540 boot_ec = NULL; 1541 return -ENODEV; 1542 } 1543 1544 static int param_set_event_clearing(const char *val, struct kernel_param *kp) 1545 { 1546 int result = 0; 1547 1548 if (!strncmp(val, "status", sizeof("status") - 1)) { 1549 ec_event_clearing = ACPI_EC_EVT_TIMING_STATUS; 1550 pr_info("Assuming SCI_EVT clearing on EC_SC accesses\n"); 1551 } else if (!strncmp(val, "query", sizeof("query") - 1)) { 1552 ec_event_clearing = ACPI_EC_EVT_TIMING_QUERY; 1553 pr_info("Assuming SCI_EVT clearing on QR_EC writes\n"); 1554 } else if (!strncmp(val, "event", sizeof("event") - 1)) { 1555 ec_event_clearing = ACPI_EC_EVT_TIMING_EVENT; 1556 pr_info("Assuming SCI_EVT clearing on event reads\n"); 1557 } else 1558 result = -EINVAL; 1559 return result; 1560 } 1561 1562 static int param_get_event_clearing(char *buffer, struct kernel_param *kp) 1563 { 1564 switch (ec_event_clearing) { 1565 case ACPI_EC_EVT_TIMING_STATUS: 1566 return sprintf(buffer, "status"); 1567 case ACPI_EC_EVT_TIMING_QUERY: 1568 return sprintf(buffer, "query"); 1569 case ACPI_EC_EVT_TIMING_EVENT: 1570 return sprintf(buffer, "event"); 1571 default: 1572 return sprintf(buffer, "invalid"); 1573 } 1574 return 0; 1575 } 1576 1577 module_param_call(ec_event_clearing, param_set_event_clearing, param_get_event_clearing, 1578 NULL, 0644); 1579 MODULE_PARM_DESC(ec_event_clearing, "Assumed SCI_EVT clearing timing"); 1580 1581 static struct acpi_driver acpi_ec_driver = { 1582 .name = "ec", 1583 .class = ACPI_EC_CLASS, 1584 .ids = ec_device_ids, 1585 .ops = { 1586 .add = acpi_ec_add, 1587 .remove = acpi_ec_remove, 1588 }, 1589 }; 1590 1591 int __init acpi_ec_init(void) 1592 { 1593 int result = 0; 1594 1595 /* Now register the driver for the EC */ 1596 result = acpi_bus_register_driver(&acpi_ec_driver); 1597 if (result < 0) 1598 return -ENODEV; 1599 1600 return result; 1601 } 1602 1603 /* EC driver currently not unloadable */ 1604 #if 0 1605 static void __exit acpi_ec_exit(void) 1606 { 1607 1608 acpi_bus_unregister_driver(&acpi_ec_driver); 1609 } 1610 #endif /* 0 */ 1611