1// SPDX-License-Identifier: GPL-2.0-or-later 2/* 3 * ec.c - ACPI Embedded Controller Driver (v3) 4 * 5 * Copyright (C) 2001-2015 Intel Corporation 6 * Author: 2014, 2015 Lv Zheng <lv.zheng@intel.com> 7 * 2006, 2007 Alexey Starikovskiy <alexey.y.starikovskiy@intel.com> 8 * 2006 Denis Sadykov <denis.m.sadykov@intel.com> 9 * 2004 Luming Yu <luming.yu@intel.com> 10 * 2001, 2002 Andy Grover <andrew.grover@intel.com> 11 * 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com> 12 * Copyright (C) 2008 Alexey Starikovskiy <astarikovskiy@suse.de> 13 */ 14 15/* Uncomment next line to get verbose printout */ 16/* #define DEBUG */ 17#define pr_fmt(fmt) "ACPI: EC: " fmt 18 19#include <linux/kernel.h> 20#include <linux/module.h> 21#include <linux/init.h> 22#include <linux/types.h> 23#include <linux/delay.h> 24#include <linux/interrupt.h> 25#include <linux/list.h> 26#include <linux/spinlock.h> 27#include <linux/slab.h> 28#include <linux/suspend.h> 29#include <linux/acpi.h> 30#include <linux/dmi.h> 31#include <asm/io.h> 32 33#include "internal.h" 34 35#define ACPI_EC_CLASS "embedded_controller" 36#define ACPI_EC_DEVICE_NAME "Embedded Controller" 37 38/* EC status register */ 39#define ACPI_EC_FLAG_OBF 0x01 /* Output buffer full */ 40#define ACPI_EC_FLAG_IBF 0x02 /* Input buffer full */ 41#define ACPI_EC_FLAG_CMD 0x08 /* Input buffer contains a command */ 42#define ACPI_EC_FLAG_BURST 0x10 /* burst mode */ 43#define ACPI_EC_FLAG_SCI 0x20 /* EC-SCI occurred */ 44 45/* 46 * The SCI_EVT clearing timing is not defined by the ACPI specification. 47 * This leads to lots of practical timing issues for the host EC driver. 48 * The following variations are defined (from the target EC firmware's 49 * perspective): 50 * STATUS: After indicating SCI_EVT edge triggered IRQ to the host, the 51 * target can clear SCI_EVT at any time so long as the host can see 52 * the indication by reading the status register (EC_SC). So the 53 * host should re-check SCI_EVT after the first time the SCI_EVT 54 * indication is seen, which is the same time the query request 55 * (QR_EC) is written to the command register (EC_CMD). SCI_EVT set 56 * at any later time could indicate another event. Normally such 57 * kind of EC firmware has implemented an event queue and will 58 * return 0x00 to indicate "no outstanding event". 59 * QUERY: After seeing the query request (QR_EC) written to the command 60 * register (EC_CMD) by the host and having prepared the responding 61 * event value in the data register (EC_DATA), the target can safely 62 * clear SCI_EVT because the target can confirm that the current 63 * event is being handled by the host. The host then should check 64 * SCI_EVT right after reading the event response from the data 65 * register (EC_DATA). 66 * EVENT: After seeing the event response read from the data register 67 * (EC_DATA) by the host, the target can clear SCI_EVT. As the 68 * target requires time to notice the change in the data register 69 * (EC_DATA), the host may be required to wait additional guarding 70 * time before checking the SCI_EVT again. Such guarding may not be 71 * necessary if the host is notified via another IRQ. 72 */ 73#define ACPI_EC_EVT_TIMING_STATUS 0x00 74#define ACPI_EC_EVT_TIMING_QUERY 0x01 75#define ACPI_EC_EVT_TIMING_EVENT 0x02 76 77/* EC commands */ 78enum ec_command { 79 ACPI_EC_COMMAND_READ = 0x80, 80 ACPI_EC_COMMAND_WRITE = 0x81, 81 ACPI_EC_BURST_ENABLE = 0x82, 82 ACPI_EC_BURST_DISABLE = 0x83, 83 ACPI_EC_COMMAND_QUERY = 0x84, 84}; 85 86#define ACPI_EC_DELAY 500 /* Wait 500ms max. during EC ops */ 87#define ACPI_EC_UDELAY_GLK 1000 /* Wait 1ms max. to get global lock */ 88#define ACPI_EC_UDELAY_POLL 550 /* Wait 1ms for EC transaction polling */ 89#define ACPI_EC_CLEAR_MAX 100 /* Maximum number of events to query 90 * when trying to clear the EC */ 91#define ACPI_EC_MAX_QUERIES 16 /* Maximum number of parallel queries */ 92 93enum { 94 EC_FLAGS_QUERY_ENABLED, /* Query is enabled */ 95 EC_FLAGS_QUERY_PENDING, /* Query is pending */ 96 EC_FLAGS_QUERY_GUARDING, /* Guard for SCI_EVT check */ 97 EC_FLAGS_EVENT_HANDLER_INSTALLED, /* Event handler installed */ 98 EC_FLAGS_EC_HANDLER_INSTALLED, /* OpReg handler installed */ 99 EC_FLAGS_QUERY_METHODS_INSTALLED, /* _Qxx handlers installed */ 100 EC_FLAGS_STARTED, /* Driver is started */ 101 EC_FLAGS_STOPPED, /* Driver is stopped */ 102 EC_FLAGS_EVENTS_MASKED, /* Events masked */ 103}; 104 105#define ACPI_EC_COMMAND_POLL 0x01 /* Available for command byte */ 106#define ACPI_EC_COMMAND_COMPLETE 0x02 /* Completed last byte */ 107 108/* ec.c is compiled in acpi namespace so this shows up as acpi.ec_delay param */ 109static unsigned int ec_delay __read_mostly = ACPI_EC_DELAY; 110module_param(ec_delay, uint, 0644); 111MODULE_PARM_DESC(ec_delay, "Timeout(ms) waited until an EC command completes"); 112 113static unsigned int ec_max_queries __read_mostly = ACPI_EC_MAX_QUERIES; 114module_param(ec_max_queries, uint, 0644); 115MODULE_PARM_DESC(ec_max_queries, "Maximum parallel _Qxx evaluations"); 116 117static bool ec_busy_polling __read_mostly; 118module_param(ec_busy_polling, bool, 0644); 119MODULE_PARM_DESC(ec_busy_polling, "Use busy polling to advance EC transaction"); 120 121static unsigned int ec_polling_guard __read_mostly = ACPI_EC_UDELAY_POLL; 122module_param(ec_polling_guard, uint, 0644); 123MODULE_PARM_DESC(ec_polling_guard, "Guard time(us) between EC accesses in polling modes"); 124 125static unsigned int ec_event_clearing __read_mostly = ACPI_EC_EVT_TIMING_QUERY; 126 127/* 128 * If the number of false interrupts per one transaction exceeds 129 * this threshold, will think there is a GPE storm happened and 130 * will disable the GPE for normal transaction. 131 */ 132static unsigned int ec_storm_threshold __read_mostly = 8; 133module_param(ec_storm_threshold, uint, 0644); 134MODULE_PARM_DESC(ec_storm_threshold, "Maxim false GPE numbers not considered as GPE storm"); 135 136static bool ec_freeze_events __read_mostly = false; 137module_param(ec_freeze_events, bool, 0644); 138MODULE_PARM_DESC(ec_freeze_events, "Disabling event handling during suspend/resume"); 139 140static bool ec_no_wakeup __read_mostly; 141module_param(ec_no_wakeup, bool, 0644); 142MODULE_PARM_DESC(ec_no_wakeup, "Do not wake up from suspend-to-idle"); 143 144struct acpi_ec_query_handler { 145 struct list_head node; 146 acpi_ec_query_func func; 147 acpi_handle handle; 148 void *data; 149 u8 query_bit; 150 struct kref kref; 151}; 152 153struct transaction { 154 const u8 *wdata; 155 u8 *rdata; 156 unsigned short irq_count; 157 u8 command; 158 u8 wi; 159 u8 ri; 160 u8 wlen; 161 u8 rlen; 162 u8 flags; 163}; 164 165struct acpi_ec_query { 166 struct transaction transaction; 167 struct work_struct work; 168 struct acpi_ec_query_handler *handler; 169 struct acpi_ec *ec; 170}; 171 172static int acpi_ec_query(struct acpi_ec *ec, u8 *data); 173static void advance_transaction(struct acpi_ec *ec); 174static void acpi_ec_event_handler(struct work_struct *work); 175static void acpi_ec_event_processor(struct work_struct *work); 176 177struct acpi_ec *first_ec; 178EXPORT_SYMBOL(first_ec); 179 180static struct acpi_ec *boot_ec; 181static bool boot_ec_is_ecdt = false; 182static struct workqueue_struct *ec_wq; 183static struct workqueue_struct *ec_query_wq; 184 185static int EC_FLAGS_CORRECT_ECDT; /* Needs ECDT port address correction */ 186static int EC_FLAGS_TRUST_DSDT_GPE; /* Needs DSDT GPE as correction setting */ 187static int EC_FLAGS_CLEAR_ON_RESUME; /* Needs acpi_ec_clear() on boot/resume */ 188 189/* -------------------------------------------------------------------------- 190 * Logging/Debugging 191 * -------------------------------------------------------------------------- */ 192 193/* 194 * Splitters used by the developers to track the boundary of the EC 195 * handling processes. 196 */ 197#ifdef DEBUG 198#define EC_DBG_SEP " " 199#define EC_DBG_DRV "+++++" 200#define EC_DBG_STM "=====" 201#define EC_DBG_REQ "*****" 202#define EC_DBG_EVT "#####" 203#else 204#define EC_DBG_SEP "" 205#define EC_DBG_DRV 206#define EC_DBG_STM 207#define EC_DBG_REQ 208#define EC_DBG_EVT 209#endif 210 211#define ec_log_raw(fmt, ...) \ 212 pr_info(fmt "\n", ##__VA_ARGS__) 213#define ec_dbg_raw(fmt, ...) \ 214 pr_debug(fmt "\n", ##__VA_ARGS__) 215#define ec_log(filter, fmt, ...) \ 216 ec_log_raw(filter EC_DBG_SEP fmt EC_DBG_SEP filter, ##__VA_ARGS__) 217#define ec_dbg(filter, fmt, ...) \ 218 ec_dbg_raw(filter EC_DBG_SEP fmt EC_DBG_SEP filter, ##__VA_ARGS__) 219 220#define ec_log_drv(fmt, ...) \ 221 ec_log(EC_DBG_DRV, fmt, ##__VA_ARGS__) 222#define ec_dbg_drv(fmt, ...) \ 223 ec_dbg(EC_DBG_DRV, fmt, ##__VA_ARGS__) 224#define ec_dbg_stm(fmt, ...) \ 225 ec_dbg(EC_DBG_STM, fmt, ##__VA_ARGS__) 226#define ec_dbg_req(fmt, ...) \ 227 ec_dbg(EC_DBG_REQ, fmt, ##__VA_ARGS__) 228#define ec_dbg_evt(fmt, ...) \ 229 ec_dbg(EC_DBG_EVT, fmt, ##__VA_ARGS__) 230#define ec_dbg_ref(ec, fmt, ...) \ 231 ec_dbg_raw("%lu: " fmt, ec->reference_count, ## __VA_ARGS__) 232 233/* -------------------------------------------------------------------------- 234 * Device Flags 235 * -------------------------------------------------------------------------- */ 236 237static bool acpi_ec_started(struct acpi_ec *ec) 238{ 239 return test_bit(EC_FLAGS_STARTED, &ec->flags) && 240 !test_bit(EC_FLAGS_STOPPED, &ec->flags); 241} 242 243static bool acpi_ec_event_enabled(struct acpi_ec *ec) 244{ 245 /* 246 * There is an OSPM early stage logic. During the early stages 247 * (boot/resume), OSPMs shouldn't enable the event handling, only 248 * the EC transactions are allowed to be performed. 249 */ 250 if (!test_bit(EC_FLAGS_QUERY_ENABLED, &ec->flags)) 251 return false; 252 /* 253 * However, disabling the event handling is experimental for late 254 * stage (suspend), and is controlled by the boot parameter of 255 * "ec_freeze_events": 256 * 1. true: The EC event handling is disabled before entering 257 * the noirq stage. 258 * 2. false: The EC event handling is automatically disabled as 259 * soon as the EC driver is stopped. 260 */ 261 if (ec_freeze_events) 262 return acpi_ec_started(ec); 263 else 264 return test_bit(EC_FLAGS_STARTED, &ec->flags); 265} 266 267static bool acpi_ec_flushed(struct acpi_ec *ec) 268{ 269 return ec->reference_count == 1; 270} 271 272/* -------------------------------------------------------------------------- 273 * EC Registers 274 * -------------------------------------------------------------------------- */ 275 276static inline u8 acpi_ec_read_status(struct acpi_ec *ec) 277{ 278 u8 x = inb(ec->command_addr); 279 280 ec_dbg_raw("EC_SC(R) = 0x%2.2x " 281 "SCI_EVT=%d BURST=%d CMD=%d IBF=%d OBF=%d", 282 x, 283 !!(x & ACPI_EC_FLAG_SCI), 284 !!(x & ACPI_EC_FLAG_BURST), 285 !!(x & ACPI_EC_FLAG_CMD), 286 !!(x & ACPI_EC_FLAG_IBF), 287 !!(x & ACPI_EC_FLAG_OBF)); 288 return x; 289} 290 291static inline u8 acpi_ec_read_data(struct acpi_ec *ec) 292{ 293 u8 x = inb(ec->data_addr); 294 295 ec->timestamp = jiffies; 296 ec_dbg_raw("EC_DATA(R) = 0x%2.2x", x); 297 return x; 298} 299 300static inline void acpi_ec_write_cmd(struct acpi_ec *ec, u8 command) 301{ 302 ec_dbg_raw("EC_SC(W) = 0x%2.2x", command); 303 outb(command, ec->command_addr); 304 ec->timestamp = jiffies; 305} 306 307static inline void acpi_ec_write_data(struct acpi_ec *ec, u8 data) 308{ 309 ec_dbg_raw("EC_DATA(W) = 0x%2.2x", data); 310 outb(data, ec->data_addr); 311 ec->timestamp = jiffies; 312} 313 314#if defined(DEBUG) || defined(CONFIG_DYNAMIC_DEBUG) 315static const char *acpi_ec_cmd_string(u8 cmd) 316{ 317 switch (cmd) { 318 case 0x80: 319 return "RD_EC"; 320 case 0x81: 321 return "WR_EC"; 322 case 0x82: 323 return "BE_EC"; 324 case 0x83: 325 return "BD_EC"; 326 case 0x84: 327 return "QR_EC"; 328 } 329 return "UNKNOWN"; 330} 331#else 332#define acpi_ec_cmd_string(cmd) "UNDEF" 333#endif 334 335/* -------------------------------------------------------------------------- 336 * GPE Registers 337 * -------------------------------------------------------------------------- */ 338 339static inline bool acpi_ec_is_gpe_raised(struct acpi_ec *ec) 340{ 341 acpi_event_status gpe_status = 0; 342 343 (void)acpi_get_gpe_status(NULL, ec->gpe, &gpe_status); 344 return (gpe_status & ACPI_EVENT_FLAG_STATUS_SET) ? true : false; 345} 346 347static inline void acpi_ec_enable_gpe(struct acpi_ec *ec, bool open) 348{ 349 if (open) 350 acpi_enable_gpe(NULL, ec->gpe); 351 else { 352 BUG_ON(ec->reference_count < 1); 353 acpi_set_gpe(NULL, ec->gpe, ACPI_GPE_ENABLE); 354 } 355 if (acpi_ec_is_gpe_raised(ec)) { 356 /* 357 * On some platforms, EN=1 writes cannot trigger GPE. So 358 * software need to manually trigger a pseudo GPE event on 359 * EN=1 writes. 360 */ 361 ec_dbg_raw("Polling quirk"); 362 advance_transaction(ec); 363 } 364} 365 366static inline void acpi_ec_disable_gpe(struct acpi_ec *ec, bool close) 367{ 368 if (close) 369 acpi_disable_gpe(NULL, ec->gpe); 370 else { 371 BUG_ON(ec->reference_count < 1); 372 acpi_set_gpe(NULL, ec->gpe, ACPI_GPE_DISABLE); 373 } 374} 375 376static inline void acpi_ec_clear_gpe(struct acpi_ec *ec) 377{ 378 /* 379 * GPE STS is a W1C register, which means: 380 * 1. Software can clear it without worrying about clearing other 381 * GPEs' STS bits when the hardware sets them in parallel. 382 * 2. As long as software can ensure only clearing it when it is 383 * set, hardware won't set it in parallel. 384 * So software can clear GPE in any contexts. 385 * Warning: do not move the check into advance_transaction() as the 386 * EC commands will be sent without GPE raised. 387 */ 388 if (!acpi_ec_is_gpe_raised(ec)) 389 return; 390 acpi_clear_gpe(NULL, ec->gpe); 391} 392 393/* -------------------------------------------------------------------------- 394 * Transaction Management 395 * -------------------------------------------------------------------------- */ 396 397static void acpi_ec_submit_request(struct acpi_ec *ec) 398{ 399 ec->reference_count++; 400 if (test_bit(EC_FLAGS_EVENT_HANDLER_INSTALLED, &ec->flags) && 401 ec->gpe >= 0 && ec->reference_count == 1) 402 acpi_ec_enable_gpe(ec, true); 403} 404 405static void acpi_ec_complete_request(struct acpi_ec *ec) 406{ 407 bool flushed = false; 408 409 ec->reference_count--; 410 if (test_bit(EC_FLAGS_EVENT_HANDLER_INSTALLED, &ec->flags) && 411 ec->gpe >= 0 && ec->reference_count == 0) 412 acpi_ec_disable_gpe(ec, true); 413 flushed = acpi_ec_flushed(ec); 414 if (flushed) 415 wake_up(&ec->wait); 416} 417 418static void acpi_ec_mask_events(struct acpi_ec *ec) 419{ 420 if (!test_bit(EC_FLAGS_EVENTS_MASKED, &ec->flags)) { 421 if (ec->gpe >= 0) 422 acpi_ec_disable_gpe(ec, false); 423 else 424 disable_irq_nosync(ec->irq); 425 426 ec_dbg_drv("Polling enabled"); 427 set_bit(EC_FLAGS_EVENTS_MASKED, &ec->flags); 428 } 429} 430 431static void acpi_ec_unmask_events(struct acpi_ec *ec) 432{ 433 if (test_bit(EC_FLAGS_EVENTS_MASKED, &ec->flags)) { 434 clear_bit(EC_FLAGS_EVENTS_MASKED, &ec->flags); 435 if (ec->gpe >= 0) 436 acpi_ec_enable_gpe(ec, false); 437 else 438 enable_irq(ec->irq); 439 440 ec_dbg_drv("Polling disabled"); 441 } 442} 443 444/* 445 * acpi_ec_submit_flushable_request() - Increase the reference count unless 446 * the flush operation is not in 447 * progress 448 * @ec: the EC device 449 * 450 * This function must be used before taking a new action that should hold 451 * the reference count. If this function returns false, then the action 452 * must be discarded or it will prevent the flush operation from being 453 * completed. 454 */ 455static bool acpi_ec_submit_flushable_request(struct acpi_ec *ec) 456{ 457 if (!acpi_ec_started(ec)) 458 return false; 459 acpi_ec_submit_request(ec); 460 return true; 461} 462 463static void acpi_ec_submit_query(struct acpi_ec *ec) 464{ 465 acpi_ec_mask_events(ec); 466 if (!acpi_ec_event_enabled(ec)) 467 return; 468 if (!test_and_set_bit(EC_FLAGS_QUERY_PENDING, &ec->flags)) { 469 ec_dbg_evt("Command(%s) submitted/blocked", 470 acpi_ec_cmd_string(ACPI_EC_COMMAND_QUERY)); 471 ec->nr_pending_queries++; 472 ec->events_in_progress++; 473 queue_work(ec_wq, &ec->work); 474 } 475} 476 477static void acpi_ec_complete_query(struct acpi_ec *ec) 478{ 479 if (test_and_clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags)) 480 ec_dbg_evt("Command(%s) unblocked", 481 acpi_ec_cmd_string(ACPI_EC_COMMAND_QUERY)); 482 acpi_ec_unmask_events(ec); 483} 484 485static inline void __acpi_ec_enable_event(struct acpi_ec *ec) 486{ 487 if (!test_and_set_bit(EC_FLAGS_QUERY_ENABLED, &ec->flags)) 488 ec_log_drv("event unblocked"); 489 /* 490 * Unconditionally invoke this once after enabling the event 491 * handling mechanism to detect the pending events. 492 */ 493 advance_transaction(ec); 494} 495 496static inline void __acpi_ec_disable_event(struct acpi_ec *ec) 497{ 498 if (test_and_clear_bit(EC_FLAGS_QUERY_ENABLED, &ec->flags)) 499 ec_log_drv("event blocked"); 500} 501 502/* 503 * Process _Q events that might have accumulated in the EC. 504 * Run with locked ec mutex. 505 */ 506static void acpi_ec_clear(struct acpi_ec *ec) 507{ 508 int i, status; 509 u8 value = 0; 510 511 for (i = 0; i < ACPI_EC_CLEAR_MAX; i++) { 512 status = acpi_ec_query(ec, &value); 513 if (status || !value) 514 break; 515 } 516 if (unlikely(i == ACPI_EC_CLEAR_MAX)) 517 pr_warn("Warning: Maximum of %d stale EC events cleared\n", i); 518 else 519 pr_info("%d stale EC events cleared\n", i); 520} 521 522static void acpi_ec_enable_event(struct acpi_ec *ec) 523{ 524 unsigned long flags; 525 526 spin_lock_irqsave(&ec->lock, flags); 527 if (acpi_ec_started(ec)) 528 __acpi_ec_enable_event(ec); 529 spin_unlock_irqrestore(&ec->lock, flags); 530 531 /* Drain additional events if hardware requires that */ 532 if (EC_FLAGS_CLEAR_ON_RESUME) 533 acpi_ec_clear(ec); 534} 535 536#ifdef CONFIG_PM_SLEEP 537static void __acpi_ec_flush_work(void) 538{ 539 flush_workqueue(ec_wq); /* flush ec->work */ 540 flush_workqueue(ec_query_wq); /* flush queries */ 541} 542 543static void acpi_ec_disable_event(struct acpi_ec *ec) 544{ 545 unsigned long flags; 546 547 spin_lock_irqsave(&ec->lock, flags); 548 __acpi_ec_disable_event(ec); 549 spin_unlock_irqrestore(&ec->lock, flags); 550 551 /* 552 * When ec_freeze_events is true, we need to flush events in 553 * the proper position before entering the noirq stage. 554 */ 555 __acpi_ec_flush_work(); 556} 557 558void acpi_ec_flush_work(void) 559{ 560 /* Without ec_wq there is nothing to flush. */ 561 if (!ec_wq) 562 return; 563 564 __acpi_ec_flush_work(); 565} 566#endif /* CONFIG_PM_SLEEP */ 567 568static bool acpi_ec_guard_event(struct acpi_ec *ec) 569{ 570 bool guarded = true; 571 unsigned long flags; 572 573 spin_lock_irqsave(&ec->lock, flags); 574 /* 575 * If firmware SCI_EVT clearing timing is "event", we actually 576 * don't know when the SCI_EVT will be cleared by firmware after 577 * evaluating _Qxx, so we need to re-check SCI_EVT after waiting an 578 * acceptable period. 579 * 580 * The guarding period begins when EC_FLAGS_QUERY_PENDING is 581 * flagged, which means SCI_EVT check has just been performed. 582 * But if the current transaction is ACPI_EC_COMMAND_QUERY, the 583 * guarding should have already been performed (via 584 * EC_FLAGS_QUERY_GUARDING) and should not be applied so that the 585 * ACPI_EC_COMMAND_QUERY transaction can be transitioned into 586 * ACPI_EC_COMMAND_POLL state immediately. 587 */ 588 if (ec_event_clearing == ACPI_EC_EVT_TIMING_STATUS || 589 ec_event_clearing == ACPI_EC_EVT_TIMING_QUERY || 590 !test_bit(EC_FLAGS_QUERY_PENDING, &ec->flags) || 591 (ec->curr && ec->curr->command == ACPI_EC_COMMAND_QUERY)) 592 guarded = false; 593 spin_unlock_irqrestore(&ec->lock, flags); 594 return guarded; 595} 596 597static int ec_transaction_polled(struct acpi_ec *ec) 598{ 599 unsigned long flags; 600 int ret = 0; 601 602 spin_lock_irqsave(&ec->lock, flags); 603 if (ec->curr && (ec->curr->flags & ACPI_EC_COMMAND_POLL)) 604 ret = 1; 605 spin_unlock_irqrestore(&ec->lock, flags); 606 return ret; 607} 608 609static int ec_transaction_completed(struct acpi_ec *ec) 610{ 611 unsigned long flags; 612 int ret = 0; 613 614 spin_lock_irqsave(&ec->lock, flags); 615 if (ec->curr && (ec->curr->flags & ACPI_EC_COMMAND_COMPLETE)) 616 ret = 1; 617 spin_unlock_irqrestore(&ec->lock, flags); 618 return ret; 619} 620 621static inline void ec_transaction_transition(struct acpi_ec *ec, unsigned long flag) 622{ 623 ec->curr->flags |= flag; 624 if (ec->curr->command == ACPI_EC_COMMAND_QUERY) { 625 if (ec_event_clearing == ACPI_EC_EVT_TIMING_STATUS && 626 flag == ACPI_EC_COMMAND_POLL) 627 acpi_ec_complete_query(ec); 628 if (ec_event_clearing == ACPI_EC_EVT_TIMING_QUERY && 629 flag == ACPI_EC_COMMAND_COMPLETE) 630 acpi_ec_complete_query(ec); 631 if (ec_event_clearing == ACPI_EC_EVT_TIMING_EVENT && 632 flag == ACPI_EC_COMMAND_COMPLETE) 633 set_bit(EC_FLAGS_QUERY_GUARDING, &ec->flags); 634 } 635} 636 637static void advance_transaction(struct acpi_ec *ec) 638{ 639 struct transaction *t; 640 u8 status; 641 bool wakeup = false; 642 643 ec_dbg_stm("%s (%d)", in_interrupt() ? "IRQ" : "TASK", 644 smp_processor_id()); 645 /* 646 * By always clearing STS before handling all indications, we can 647 * ensure a hardware STS 0->1 change after this clearing can always 648 * trigger a GPE interrupt. 649 */ 650 if (ec->gpe >= 0) 651 acpi_ec_clear_gpe(ec); 652 653 status = acpi_ec_read_status(ec); 654 t = ec->curr; 655 /* 656 * Another IRQ or a guarded polling mode advancement is detected, 657 * the next QR_EC submission is then allowed. 658 */ 659 if (!t || !(t->flags & ACPI_EC_COMMAND_POLL)) { 660 if (ec_event_clearing == ACPI_EC_EVT_TIMING_EVENT && 661 (!ec->nr_pending_queries || 662 test_bit(EC_FLAGS_QUERY_GUARDING, &ec->flags))) { 663 clear_bit(EC_FLAGS_QUERY_GUARDING, &ec->flags); 664 acpi_ec_complete_query(ec); 665 } 666 } 667 if (!t) 668 goto err; 669 if (t->flags & ACPI_EC_COMMAND_POLL) { 670 if (t->wlen > t->wi) { 671 if ((status & ACPI_EC_FLAG_IBF) == 0) 672 acpi_ec_write_data(ec, t->wdata[t->wi++]); 673 else 674 goto err; 675 } else if (t->rlen > t->ri) { 676 if ((status & ACPI_EC_FLAG_OBF) == 1) { 677 t->rdata[t->ri++] = acpi_ec_read_data(ec); 678 if (t->rlen == t->ri) { 679 ec_transaction_transition(ec, ACPI_EC_COMMAND_COMPLETE); 680 if (t->command == ACPI_EC_COMMAND_QUERY) 681 ec_dbg_evt("Command(%s) completed by hardware", 682 acpi_ec_cmd_string(ACPI_EC_COMMAND_QUERY)); 683 wakeup = true; 684 } 685 } else 686 goto err; 687 } else if (t->wlen == t->wi && 688 (status & ACPI_EC_FLAG_IBF) == 0) { 689 ec_transaction_transition(ec, ACPI_EC_COMMAND_COMPLETE); 690 wakeup = true; 691 } 692 goto out; 693 } else if (!(status & ACPI_EC_FLAG_IBF)) { 694 acpi_ec_write_cmd(ec, t->command); 695 ec_transaction_transition(ec, ACPI_EC_COMMAND_POLL); 696 goto out; 697 } 698err: 699 /* 700 * If SCI bit is set, then don't think it's a false IRQ 701 * otherwise will take a not handled IRQ as a false one. 702 */ 703 if (!(status & ACPI_EC_FLAG_SCI)) { 704 if (in_interrupt() && t) { 705 if (t->irq_count < ec_storm_threshold) 706 ++t->irq_count; 707 /* Allow triggering on 0 threshold */ 708 if (t->irq_count == ec_storm_threshold) 709 acpi_ec_mask_events(ec); 710 } 711 } 712out: 713 if (status & ACPI_EC_FLAG_SCI) 714 acpi_ec_submit_query(ec); 715 if (wakeup && in_interrupt()) 716 wake_up(&ec->wait); 717} 718 719static void start_transaction(struct acpi_ec *ec) 720{ 721 ec->curr->irq_count = ec->curr->wi = ec->curr->ri = 0; 722 ec->curr->flags = 0; 723} 724 725static int ec_guard(struct acpi_ec *ec) 726{ 727 unsigned long guard = usecs_to_jiffies(ec->polling_guard); 728 unsigned long timeout = ec->timestamp + guard; 729 730 /* Ensure guarding period before polling EC status */ 731 do { 732 if (ec->busy_polling) { 733 /* Perform busy polling */ 734 if (ec_transaction_completed(ec)) 735 return 0; 736 udelay(jiffies_to_usecs(guard)); 737 } else { 738 /* 739 * Perform wait polling 740 * 1. Wait the transaction to be completed by the 741 * GPE handler after the transaction enters 742 * ACPI_EC_COMMAND_POLL state. 743 * 2. A special guarding logic is also required 744 * for event clearing mode "event" before the 745 * transaction enters ACPI_EC_COMMAND_POLL 746 * state. 747 */ 748 if (!ec_transaction_polled(ec) && 749 !acpi_ec_guard_event(ec)) 750 break; 751 if (wait_event_timeout(ec->wait, 752 ec_transaction_completed(ec), 753 guard)) 754 return 0; 755 } 756 } while (time_before(jiffies, timeout)); 757 return -ETIME; 758} 759 760static int ec_poll(struct acpi_ec *ec) 761{ 762 unsigned long flags; 763 int repeat = 5; /* number of command restarts */ 764 765 while (repeat--) { 766 unsigned long delay = jiffies + 767 msecs_to_jiffies(ec_delay); 768 do { 769 if (!ec_guard(ec)) 770 return 0; 771 spin_lock_irqsave(&ec->lock, flags); 772 advance_transaction(ec); 773 spin_unlock_irqrestore(&ec->lock, flags); 774 } while (time_before(jiffies, delay)); 775 pr_debug("controller reset, restart transaction\n"); 776 spin_lock_irqsave(&ec->lock, flags); 777 start_transaction(ec); 778 spin_unlock_irqrestore(&ec->lock, flags); 779 } 780 return -ETIME; 781} 782 783static int acpi_ec_transaction_unlocked(struct acpi_ec *ec, 784 struct transaction *t) 785{ 786 unsigned long tmp; 787 int ret = 0; 788 789 /* start transaction */ 790 spin_lock_irqsave(&ec->lock, tmp); 791 /* Enable GPE for command processing (IBF=0/OBF=1) */ 792 if (!acpi_ec_submit_flushable_request(ec)) { 793 ret = -EINVAL; 794 goto unlock; 795 } 796 ec_dbg_ref(ec, "Increase command"); 797 /* following two actions should be kept atomic */ 798 ec->curr = t; 799 ec_dbg_req("Command(%s) started", acpi_ec_cmd_string(t->command)); 800 start_transaction(ec); 801 spin_unlock_irqrestore(&ec->lock, tmp); 802 803 ret = ec_poll(ec); 804 805 spin_lock_irqsave(&ec->lock, tmp); 806 if (t->irq_count == ec_storm_threshold) 807 acpi_ec_unmask_events(ec); 808 ec_dbg_req("Command(%s) stopped", acpi_ec_cmd_string(t->command)); 809 ec->curr = NULL; 810 /* Disable GPE for command processing (IBF=0/OBF=1) */ 811 acpi_ec_complete_request(ec); 812 ec_dbg_ref(ec, "Decrease command"); 813unlock: 814 spin_unlock_irqrestore(&ec->lock, tmp); 815 return ret; 816} 817 818static int acpi_ec_transaction(struct acpi_ec *ec, struct transaction *t) 819{ 820 int status; 821 u32 glk; 822 823 if (!ec || (!t) || (t->wlen && !t->wdata) || (t->rlen && !t->rdata)) 824 return -EINVAL; 825 if (t->rdata) 826 memset(t->rdata, 0, t->rlen); 827 828 mutex_lock(&ec->mutex); 829 if (ec->global_lock) { 830 status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk); 831 if (ACPI_FAILURE(status)) { 832 status = -ENODEV; 833 goto unlock; 834 } 835 } 836 837 status = acpi_ec_transaction_unlocked(ec, t); 838 839 if (ec->global_lock) 840 acpi_release_global_lock(glk); 841unlock: 842 mutex_unlock(&ec->mutex); 843 return status; 844} 845 846static int acpi_ec_burst_enable(struct acpi_ec *ec) 847{ 848 u8 d; 849 struct transaction t = {.command = ACPI_EC_BURST_ENABLE, 850 .wdata = NULL, .rdata = &d, 851 .wlen = 0, .rlen = 1}; 852 853 return acpi_ec_transaction(ec, &t); 854} 855 856static int acpi_ec_burst_disable(struct acpi_ec *ec) 857{ 858 struct transaction t = {.command = ACPI_EC_BURST_DISABLE, 859 .wdata = NULL, .rdata = NULL, 860 .wlen = 0, .rlen = 0}; 861 862 return (acpi_ec_read_status(ec) & ACPI_EC_FLAG_BURST) ? 863 acpi_ec_transaction(ec, &t) : 0; 864} 865 866static int acpi_ec_read(struct acpi_ec *ec, u8 address, u8 *data) 867{ 868 int result; 869 u8 d; 870 struct transaction t = {.command = ACPI_EC_COMMAND_READ, 871 .wdata = &address, .rdata = &d, 872 .wlen = 1, .rlen = 1}; 873 874 result = acpi_ec_transaction(ec, &t); 875 *data = d; 876 return result; 877} 878 879static int acpi_ec_write(struct acpi_ec *ec, u8 address, u8 data) 880{ 881 u8 wdata[2] = { address, data }; 882 struct transaction t = {.command = ACPI_EC_COMMAND_WRITE, 883 .wdata = wdata, .rdata = NULL, 884 .wlen = 2, .rlen = 0}; 885 886 return acpi_ec_transaction(ec, &t); 887} 888 889int ec_read(u8 addr, u8 *val) 890{ 891 int err; 892 u8 temp_data; 893 894 if (!first_ec) 895 return -ENODEV; 896 897 err = acpi_ec_read(first_ec, addr, &temp_data); 898 899 if (!err) { 900 *val = temp_data; 901 return 0; 902 } 903 return err; 904} 905EXPORT_SYMBOL(ec_read); 906 907int ec_write(u8 addr, u8 val) 908{ 909 int err; 910 911 if (!first_ec) 912 return -ENODEV; 913 914 err = acpi_ec_write(first_ec, addr, val); 915 916 return err; 917} 918EXPORT_SYMBOL(ec_write); 919 920int ec_transaction(u8 command, 921 const u8 *wdata, unsigned wdata_len, 922 u8 *rdata, unsigned rdata_len) 923{ 924 struct transaction t = {.command = command, 925 .wdata = wdata, .rdata = rdata, 926 .wlen = wdata_len, .rlen = rdata_len}; 927 928 if (!first_ec) 929 return -ENODEV; 930 931 return acpi_ec_transaction(first_ec, &t); 932} 933EXPORT_SYMBOL(ec_transaction); 934 935/* Get the handle to the EC device */ 936acpi_handle ec_get_handle(void) 937{ 938 if (!first_ec) 939 return NULL; 940 return first_ec->handle; 941} 942EXPORT_SYMBOL(ec_get_handle); 943 944static void acpi_ec_start(struct acpi_ec *ec, bool resuming) 945{ 946 unsigned long flags; 947 948 spin_lock_irqsave(&ec->lock, flags); 949 if (!test_and_set_bit(EC_FLAGS_STARTED, &ec->flags)) { 950 ec_dbg_drv("Starting EC"); 951 /* Enable GPE for event processing (SCI_EVT=1) */ 952 if (!resuming) { 953 acpi_ec_submit_request(ec); 954 ec_dbg_ref(ec, "Increase driver"); 955 } 956 ec_log_drv("EC started"); 957 } 958 spin_unlock_irqrestore(&ec->lock, flags); 959} 960 961static bool acpi_ec_stopped(struct acpi_ec *ec) 962{ 963 unsigned long flags; 964 bool flushed; 965 966 spin_lock_irqsave(&ec->lock, flags); 967 flushed = acpi_ec_flushed(ec); 968 spin_unlock_irqrestore(&ec->lock, flags); 969 return flushed; 970} 971 972static void acpi_ec_stop(struct acpi_ec *ec, bool suspending) 973{ 974 unsigned long flags; 975 976 spin_lock_irqsave(&ec->lock, flags); 977 if (acpi_ec_started(ec)) { 978 ec_dbg_drv("Stopping EC"); 979 set_bit(EC_FLAGS_STOPPED, &ec->flags); 980 spin_unlock_irqrestore(&ec->lock, flags); 981 wait_event(ec->wait, acpi_ec_stopped(ec)); 982 spin_lock_irqsave(&ec->lock, flags); 983 /* Disable GPE for event processing (SCI_EVT=1) */ 984 if (!suspending) { 985 acpi_ec_complete_request(ec); 986 ec_dbg_ref(ec, "Decrease driver"); 987 } else if (!ec_freeze_events) 988 __acpi_ec_disable_event(ec); 989 clear_bit(EC_FLAGS_STARTED, &ec->flags); 990 clear_bit(EC_FLAGS_STOPPED, &ec->flags); 991 ec_log_drv("EC stopped"); 992 } 993 spin_unlock_irqrestore(&ec->lock, flags); 994} 995 996static void acpi_ec_enter_noirq(struct acpi_ec *ec) 997{ 998 unsigned long flags; 999 1000 spin_lock_irqsave(&ec->lock, flags); 1001 ec->busy_polling = true; 1002 ec->polling_guard = 0; 1003 ec_log_drv("interrupt blocked"); 1004 spin_unlock_irqrestore(&ec->lock, flags); 1005} 1006 1007static void acpi_ec_leave_noirq(struct acpi_ec *ec) 1008{ 1009 unsigned long flags; 1010 1011 spin_lock_irqsave(&ec->lock, flags); 1012 ec->busy_polling = ec_busy_polling; 1013 ec->polling_guard = ec_polling_guard; 1014 ec_log_drv("interrupt unblocked"); 1015 spin_unlock_irqrestore(&ec->lock, flags); 1016} 1017 1018void acpi_ec_block_transactions(void) 1019{ 1020 struct acpi_ec *ec = first_ec; 1021 1022 if (!ec) 1023 return; 1024 1025 mutex_lock(&ec->mutex); 1026 /* Prevent transactions from being carried out */ 1027 acpi_ec_stop(ec, true); 1028 mutex_unlock(&ec->mutex); 1029} 1030 1031void acpi_ec_unblock_transactions(void) 1032{ 1033 /* 1034 * Allow transactions to happen again (this function is called from 1035 * atomic context during wakeup, so we don't need to acquire the mutex). 1036 */ 1037 if (first_ec) 1038 acpi_ec_start(first_ec, true); 1039} 1040 1041/* -------------------------------------------------------------------------- 1042 Event Management 1043 -------------------------------------------------------------------------- */ 1044static struct acpi_ec_query_handler * 1045acpi_ec_get_query_handler_by_value(struct acpi_ec *ec, u8 value) 1046{ 1047 struct acpi_ec_query_handler *handler; 1048 1049 mutex_lock(&ec->mutex); 1050 list_for_each_entry(handler, &ec->list, node) { 1051 if (value == handler->query_bit) { 1052 kref_get(&handler->kref); 1053 mutex_unlock(&ec->mutex); 1054 return handler; 1055 } 1056 } 1057 mutex_unlock(&ec->mutex); 1058 return NULL; 1059} 1060 1061static void acpi_ec_query_handler_release(struct kref *kref) 1062{ 1063 struct acpi_ec_query_handler *handler = 1064 container_of(kref, struct acpi_ec_query_handler, kref); 1065 1066 kfree(handler); 1067} 1068 1069static void acpi_ec_put_query_handler(struct acpi_ec_query_handler *handler) 1070{ 1071 kref_put(&handler->kref, acpi_ec_query_handler_release); 1072} 1073 1074int acpi_ec_add_query_handler(struct acpi_ec *ec, u8 query_bit, 1075 acpi_handle handle, acpi_ec_query_func func, 1076 void *data) 1077{ 1078 struct acpi_ec_query_handler *handler = 1079 kzalloc(sizeof(struct acpi_ec_query_handler), GFP_KERNEL); 1080 1081 if (!handler) 1082 return -ENOMEM; 1083 1084 handler->query_bit = query_bit; 1085 handler->handle = handle; 1086 handler->func = func; 1087 handler->data = data; 1088 mutex_lock(&ec->mutex); 1089 kref_init(&handler->kref); 1090 list_add(&handler->node, &ec->list); 1091 mutex_unlock(&ec->mutex); 1092 return 0; 1093} 1094EXPORT_SYMBOL_GPL(acpi_ec_add_query_handler); 1095 1096static void acpi_ec_remove_query_handlers(struct acpi_ec *ec, 1097 bool remove_all, u8 query_bit) 1098{ 1099 struct acpi_ec_query_handler *handler, *tmp; 1100 LIST_HEAD(free_list); 1101 1102 mutex_lock(&ec->mutex); 1103 list_for_each_entry_safe(handler, tmp, &ec->list, node) { 1104 if (remove_all || query_bit == handler->query_bit) { 1105 list_del_init(&handler->node); 1106 list_add(&handler->node, &free_list); 1107 } 1108 } 1109 mutex_unlock(&ec->mutex); 1110 list_for_each_entry_safe(handler, tmp, &free_list, node) 1111 acpi_ec_put_query_handler(handler); 1112} 1113 1114void acpi_ec_remove_query_handler(struct acpi_ec *ec, u8 query_bit) 1115{ 1116 acpi_ec_remove_query_handlers(ec, false, query_bit); 1117 flush_workqueue(ec_query_wq); 1118} 1119EXPORT_SYMBOL_GPL(acpi_ec_remove_query_handler); 1120 1121static struct acpi_ec_query *acpi_ec_create_query(struct acpi_ec *ec, u8 *pval) 1122{ 1123 struct acpi_ec_query *q; 1124 struct transaction *t; 1125 1126 q = kzalloc(sizeof (struct acpi_ec_query), GFP_KERNEL); 1127 if (!q) 1128 return NULL; 1129 1130 INIT_WORK(&q->work, acpi_ec_event_processor); 1131 t = &q->transaction; 1132 t->command = ACPI_EC_COMMAND_QUERY; 1133 t->rdata = pval; 1134 t->rlen = 1; 1135 q->ec = ec; 1136 return q; 1137} 1138 1139static void acpi_ec_delete_query(struct acpi_ec_query *q) 1140{ 1141 if (q) { 1142 if (q->handler) 1143 acpi_ec_put_query_handler(q->handler); 1144 kfree(q); 1145 } 1146} 1147 1148static void acpi_ec_event_processor(struct work_struct *work) 1149{ 1150 struct acpi_ec_query *q = container_of(work, struct acpi_ec_query, work); 1151 struct acpi_ec_query_handler *handler = q->handler; 1152 struct acpi_ec *ec = q->ec; 1153 1154 ec_dbg_evt("Query(0x%02x) started", handler->query_bit); 1155 1156 if (handler->func) 1157 handler->func(handler->data); 1158 else if (handler->handle) 1159 acpi_evaluate_object(handler->handle, NULL, NULL, NULL); 1160 1161 ec_dbg_evt("Query(0x%02x) stopped", handler->query_bit); 1162 1163 spin_lock_irq(&ec->lock); 1164 ec->queries_in_progress--; 1165 spin_unlock_irq(&ec->lock); 1166 1167 acpi_ec_delete_query(q); 1168} 1169 1170static int acpi_ec_query(struct acpi_ec *ec, u8 *data) 1171{ 1172 u8 value = 0; 1173 int result; 1174 struct acpi_ec_query *q; 1175 1176 q = acpi_ec_create_query(ec, &value); 1177 if (!q) 1178 return -ENOMEM; 1179 1180 /* 1181 * Query the EC to find out which _Qxx method we need to evaluate. 1182 * Note that successful completion of the query causes the ACPI_EC_SCI 1183 * bit to be cleared (and thus clearing the interrupt source). 1184 */ 1185 result = acpi_ec_transaction(ec, &q->transaction); 1186 if (!value) 1187 result = -ENODATA; 1188 if (result) 1189 goto err_exit; 1190 1191 q->handler = acpi_ec_get_query_handler_by_value(ec, value); 1192 if (!q->handler) { 1193 result = -ENODATA; 1194 goto err_exit; 1195 } 1196 1197 /* 1198 * It is reported that _Qxx are evaluated in a parallel way on Windows: 1199 * https://bugzilla.kernel.org/show_bug.cgi?id=94411 1200 * 1201 * Put this log entry before queue_work() to make it appear in the log 1202 * before any other messages emitted during workqueue handling. 1203 */ 1204 ec_dbg_evt("Query(0x%02x) scheduled", value); 1205 1206 spin_lock_irq(&ec->lock); 1207 1208 ec->queries_in_progress++; 1209 queue_work(ec_query_wq, &q->work); 1210 1211 spin_unlock_irq(&ec->lock); 1212 1213err_exit: 1214 if (result) 1215 acpi_ec_delete_query(q); 1216 if (data) 1217 *data = value; 1218 return result; 1219} 1220 1221static void acpi_ec_check_event(struct acpi_ec *ec) 1222{ 1223 unsigned long flags; 1224 1225 if (ec_event_clearing == ACPI_EC_EVT_TIMING_EVENT) { 1226 if (ec_guard(ec)) { 1227 spin_lock_irqsave(&ec->lock, flags); 1228 /* 1229 * Take care of the SCI_EVT unless no one else is 1230 * taking care of it. 1231 */ 1232 if (!ec->curr) 1233 advance_transaction(ec); 1234 spin_unlock_irqrestore(&ec->lock, flags); 1235 } 1236 } 1237} 1238 1239static void acpi_ec_event_handler(struct work_struct *work) 1240{ 1241 unsigned long flags; 1242 struct acpi_ec *ec = container_of(work, struct acpi_ec, work); 1243 1244 ec_dbg_evt("Event started"); 1245 1246 spin_lock_irqsave(&ec->lock, flags); 1247 while (ec->nr_pending_queries) { 1248 spin_unlock_irqrestore(&ec->lock, flags); 1249 (void)acpi_ec_query(ec, NULL); 1250 spin_lock_irqsave(&ec->lock, flags); 1251 ec->nr_pending_queries--; 1252 /* 1253 * Before exit, make sure that this work item can be 1254 * scheduled again. There might be QR_EC failures, leaving 1255 * EC_FLAGS_QUERY_PENDING uncleared and preventing this work 1256 * item from being scheduled again. 1257 */ 1258 if (!ec->nr_pending_queries) { 1259 if (ec_event_clearing == ACPI_EC_EVT_TIMING_STATUS || 1260 ec_event_clearing == ACPI_EC_EVT_TIMING_QUERY) 1261 acpi_ec_complete_query(ec); 1262 } 1263 } 1264 spin_unlock_irqrestore(&ec->lock, flags); 1265 1266 ec_dbg_evt("Event stopped"); 1267 1268 acpi_ec_check_event(ec); 1269 1270 spin_lock_irqsave(&ec->lock, flags); 1271 ec->events_in_progress--; 1272 spin_unlock_irqrestore(&ec->lock, flags); 1273} 1274 1275static void acpi_ec_handle_interrupt(struct acpi_ec *ec) 1276{ 1277 unsigned long flags; 1278 1279 spin_lock_irqsave(&ec->lock, flags); 1280 advance_transaction(ec); 1281 spin_unlock_irqrestore(&ec->lock, flags); 1282} 1283 1284static u32 acpi_ec_gpe_handler(acpi_handle gpe_device, 1285 u32 gpe_number, void *data) 1286{ 1287 acpi_ec_handle_interrupt(data); 1288 return ACPI_INTERRUPT_HANDLED; 1289} 1290 1291static irqreturn_t acpi_ec_irq_handler(int irq, void *data) 1292{ 1293 acpi_ec_handle_interrupt(data); 1294 return IRQ_HANDLED; 1295} 1296 1297/* -------------------------------------------------------------------------- 1298 * Address Space Management 1299 * -------------------------------------------------------------------------- */ 1300 1301static acpi_status 1302acpi_ec_space_handler(u32 function, acpi_physical_address address, 1303 u32 bits, u64 *value64, 1304 void *handler_context, void *region_context) 1305{ 1306 struct acpi_ec *ec = handler_context; 1307 int result = 0, i, bytes = bits / 8; 1308 u8 *value = (u8 *)value64; 1309 1310 if ((address > 0xFF) || !value || !handler_context) 1311 return AE_BAD_PARAMETER; 1312 1313 if (function != ACPI_READ && function != ACPI_WRITE) 1314 return AE_BAD_PARAMETER; 1315 1316 if (ec->busy_polling || bits > 8) 1317 acpi_ec_burst_enable(ec); 1318 1319 for (i = 0; i < bytes; ++i, ++address, ++value) 1320 result = (function == ACPI_READ) ? 1321 acpi_ec_read(ec, address, value) : 1322 acpi_ec_write(ec, address, *value); 1323 1324 if (ec->busy_polling || bits > 8) 1325 acpi_ec_burst_disable(ec); 1326 1327 switch (result) { 1328 case -EINVAL: 1329 return AE_BAD_PARAMETER; 1330 case -ENODEV: 1331 return AE_NOT_FOUND; 1332 case -ETIME: 1333 return AE_TIME; 1334 default: 1335 return AE_OK; 1336 } 1337} 1338 1339/* -------------------------------------------------------------------------- 1340 * Driver Interface 1341 * -------------------------------------------------------------------------- */ 1342 1343static acpi_status 1344ec_parse_io_ports(struct acpi_resource *resource, void *context); 1345 1346static void acpi_ec_free(struct acpi_ec *ec) 1347{ 1348 if (first_ec == ec) 1349 first_ec = NULL; 1350 if (boot_ec == ec) 1351 boot_ec = NULL; 1352 kfree(ec); 1353} 1354 1355static struct acpi_ec *acpi_ec_alloc(void) 1356{ 1357 struct acpi_ec *ec = kzalloc(sizeof(struct acpi_ec), GFP_KERNEL); 1358 1359 if (!ec) 1360 return NULL; 1361 mutex_init(&ec->mutex); 1362 init_waitqueue_head(&ec->wait); 1363 INIT_LIST_HEAD(&ec->list); 1364 spin_lock_init(&ec->lock); 1365 INIT_WORK(&ec->work, acpi_ec_event_handler); 1366 ec->timestamp = jiffies; 1367 ec->busy_polling = true; 1368 ec->polling_guard = 0; 1369 ec->gpe = -1; 1370 ec->irq = -1; 1371 return ec; 1372} 1373 1374static acpi_status 1375acpi_ec_register_query_methods(acpi_handle handle, u32 level, 1376 void *context, void **return_value) 1377{ 1378 char node_name[5]; 1379 struct acpi_buffer buffer = { sizeof(node_name), node_name }; 1380 struct acpi_ec *ec = context; 1381 int value = 0; 1382 acpi_status status; 1383 1384 status = acpi_get_name(handle, ACPI_SINGLE_NAME, &buffer); 1385 1386 if (ACPI_SUCCESS(status) && sscanf(node_name, "_Q%x", &value) == 1) 1387 acpi_ec_add_query_handler(ec, value, handle, NULL, NULL); 1388 return AE_OK; 1389} 1390 1391static acpi_status 1392ec_parse_device(acpi_handle handle, u32 Level, void *context, void **retval) 1393{ 1394 acpi_status status; 1395 unsigned long long tmp = 0; 1396 struct acpi_ec *ec = context; 1397 1398 /* clear addr values, ec_parse_io_ports depend on it */ 1399 ec->command_addr = ec->data_addr = 0; 1400 1401 status = acpi_walk_resources(handle, METHOD_NAME__CRS, 1402 ec_parse_io_ports, ec); 1403 if (ACPI_FAILURE(status)) 1404 return status; 1405 if (ec->data_addr == 0 || ec->command_addr == 0) 1406 return AE_OK; 1407 1408 /* Get GPE bit assignment (EC events). */ 1409 /* TODO: Add support for _GPE returning a package */ 1410 status = acpi_evaluate_integer(handle, "_GPE", NULL, &tmp); 1411 if (ACPI_SUCCESS(status)) 1412 ec->gpe = tmp; 1413 /* 1414 * Errors are non-fatal, allowing for ACPI Reduced Hardware 1415 * platforms which use GpioInt instead of GPE. 1416 */ 1417 1418 /* Use the global lock for all EC transactions? */ 1419 tmp = 0; 1420 acpi_evaluate_integer(handle, "_GLK", NULL, &tmp); 1421 ec->global_lock = tmp; 1422 ec->handle = handle; 1423 return AE_CTRL_TERMINATE; 1424} 1425 1426static bool install_gpe_event_handler(struct acpi_ec *ec) 1427{ 1428 acpi_status status; 1429 1430 status = acpi_install_gpe_raw_handler(NULL, ec->gpe, 1431 ACPI_GPE_EDGE_TRIGGERED, 1432 &acpi_ec_gpe_handler, ec); 1433 if (ACPI_FAILURE(status)) 1434 return false; 1435 1436 if (test_bit(EC_FLAGS_STARTED, &ec->flags) && ec->reference_count >= 1) 1437 acpi_ec_enable_gpe(ec, true); 1438 1439 return true; 1440} 1441 1442static bool install_gpio_irq_event_handler(struct acpi_ec *ec) 1443{ 1444 return request_irq(ec->irq, acpi_ec_irq_handler, IRQF_SHARED, 1445 "ACPI EC", ec) >= 0; 1446} 1447 1448/** 1449 * ec_install_handlers - Install service callbacks and register query methods. 1450 * @ec: Target EC. 1451 * @device: ACPI device object corresponding to @ec. 1452 * 1453 * Install a handler for the EC address space type unless it has been installed 1454 * already. If @device is not NULL, also look for EC query methods in the 1455 * namespace and register them, and install an event (either GPE or GPIO IRQ) 1456 * handler for the EC, if possible. 1457 * 1458 * Return: 1459 * -ENODEV if the address space handler cannot be installed, which means 1460 * "unable to handle transactions", 1461 * -EPROBE_DEFER if GPIO IRQ acquisition needs to be deferred, 1462 * or 0 (success) otherwise. 1463 */ 1464static int ec_install_handlers(struct acpi_ec *ec, struct acpi_device *device) 1465{ 1466 acpi_status status; 1467 1468 acpi_ec_start(ec, false); 1469 1470 if (!test_bit(EC_FLAGS_EC_HANDLER_INSTALLED, &ec->flags)) { 1471 acpi_ec_enter_noirq(ec); 1472 status = acpi_install_address_space_handler(ec->handle, 1473 ACPI_ADR_SPACE_EC, 1474 &acpi_ec_space_handler, 1475 NULL, ec); 1476 if (ACPI_FAILURE(status)) { 1477 acpi_ec_stop(ec, false); 1478 return -ENODEV; 1479 } 1480 set_bit(EC_FLAGS_EC_HANDLER_INSTALLED, &ec->flags); 1481 } 1482 1483 if (!device) 1484 return 0; 1485 1486 if (ec->gpe < 0) { 1487 /* ACPI reduced hardware platforms use a GpioInt from _CRS. */ 1488 int irq = acpi_dev_gpio_irq_get(device, 0); 1489 /* 1490 * Bail out right away for deferred probing or complete the 1491 * initialization regardless of any other errors. 1492 */ 1493 if (irq == -EPROBE_DEFER) 1494 return -EPROBE_DEFER; 1495 else if (irq >= 0) 1496 ec->irq = irq; 1497 } 1498 1499 if (!test_bit(EC_FLAGS_QUERY_METHODS_INSTALLED, &ec->flags)) { 1500 /* Find and register all query methods */ 1501 acpi_walk_namespace(ACPI_TYPE_METHOD, ec->handle, 1, 1502 acpi_ec_register_query_methods, 1503 NULL, ec, NULL); 1504 set_bit(EC_FLAGS_QUERY_METHODS_INSTALLED, &ec->flags); 1505 } 1506 if (!test_bit(EC_FLAGS_EVENT_HANDLER_INSTALLED, &ec->flags)) { 1507 bool ready = false; 1508 1509 if (ec->gpe >= 0) 1510 ready = install_gpe_event_handler(ec); 1511 else if (ec->irq >= 0) 1512 ready = install_gpio_irq_event_handler(ec); 1513 1514 if (ready) { 1515 set_bit(EC_FLAGS_EVENT_HANDLER_INSTALLED, &ec->flags); 1516 acpi_ec_leave_noirq(ec); 1517 } 1518 /* 1519 * Failures to install an event handler are not fatal, because 1520 * the EC can be polled for events. 1521 */ 1522 } 1523 /* EC is fully operational, allow queries */ 1524 acpi_ec_enable_event(ec); 1525 1526 return 0; 1527} 1528 1529static void ec_remove_handlers(struct acpi_ec *ec) 1530{ 1531 if (test_bit(EC_FLAGS_EC_HANDLER_INSTALLED, &ec->flags)) { 1532 if (ACPI_FAILURE(acpi_remove_address_space_handler(ec->handle, 1533 ACPI_ADR_SPACE_EC, &acpi_ec_space_handler))) 1534 pr_err("failed to remove space handler\n"); 1535 clear_bit(EC_FLAGS_EC_HANDLER_INSTALLED, &ec->flags); 1536 } 1537 1538 /* 1539 * Stops handling the EC transactions after removing the operation 1540 * region handler. This is required because _REG(DISCONNECT) 1541 * invoked during the removal can result in new EC transactions. 1542 * 1543 * Flushes the EC requests and thus disables the GPE before 1544 * removing the GPE handler. This is required by the current ACPICA 1545 * GPE core. ACPICA GPE core will automatically disable a GPE when 1546 * it is indicated but there is no way to handle it. So the drivers 1547 * must disable the GPEs prior to removing the GPE handlers. 1548 */ 1549 acpi_ec_stop(ec, false); 1550 1551 if (test_bit(EC_FLAGS_EVENT_HANDLER_INSTALLED, &ec->flags)) { 1552 if (ec->gpe >= 0 && 1553 ACPI_FAILURE(acpi_remove_gpe_handler(NULL, ec->gpe, 1554 &acpi_ec_gpe_handler))) 1555 pr_err("failed to remove gpe handler\n"); 1556 1557 if (ec->irq >= 0) 1558 free_irq(ec->irq, ec); 1559 1560 clear_bit(EC_FLAGS_EVENT_HANDLER_INSTALLED, &ec->flags); 1561 } 1562 if (test_bit(EC_FLAGS_QUERY_METHODS_INSTALLED, &ec->flags)) { 1563 acpi_ec_remove_query_handlers(ec, true, 0); 1564 clear_bit(EC_FLAGS_QUERY_METHODS_INSTALLED, &ec->flags); 1565 } 1566} 1567 1568static int acpi_ec_setup(struct acpi_ec *ec, struct acpi_device *device) 1569{ 1570 int ret; 1571 1572 ret = ec_install_handlers(ec, device); 1573 if (ret) 1574 return ret; 1575 1576 /* First EC capable of handling transactions */ 1577 if (!first_ec) 1578 first_ec = ec; 1579 1580 pr_info("EC_CMD/EC_SC=0x%lx, EC_DATA=0x%lx\n", ec->command_addr, 1581 ec->data_addr); 1582 1583 if (test_bit(EC_FLAGS_EVENT_HANDLER_INSTALLED, &ec->flags)) { 1584 if (ec->gpe >= 0) 1585 pr_info("GPE=0x%x\n", ec->gpe); 1586 else 1587 pr_info("IRQ=%d\n", ec->irq); 1588 } 1589 1590 return ret; 1591} 1592 1593static int acpi_ec_add(struct acpi_device *device) 1594{ 1595 struct acpi_ec *ec; 1596 int ret; 1597 1598 strcpy(acpi_device_name(device), ACPI_EC_DEVICE_NAME); 1599 strcpy(acpi_device_class(device), ACPI_EC_CLASS); 1600 1601 if (boot_ec && (boot_ec->handle == device->handle || 1602 !strcmp(acpi_device_hid(device), ACPI_ECDT_HID))) { 1603 /* Fast path: this device corresponds to the boot EC. */ 1604 ec = boot_ec; 1605 } else { 1606 acpi_status status; 1607 1608 ec = acpi_ec_alloc(); 1609 if (!ec) 1610 return -ENOMEM; 1611 1612 status = ec_parse_device(device->handle, 0, ec, NULL); 1613 if (status != AE_CTRL_TERMINATE) { 1614 ret = -EINVAL; 1615 goto err; 1616 } 1617 1618 if (boot_ec && ec->command_addr == boot_ec->command_addr && 1619 ec->data_addr == boot_ec->data_addr && 1620 !EC_FLAGS_TRUST_DSDT_GPE) { 1621 /* 1622 * Trust PNP0C09 namespace location rather than 1623 * ECDT ID. But trust ECDT GPE rather than _GPE 1624 * because of ASUS quirks, so do not change 1625 * boot_ec->gpe to ec->gpe. 1626 */ 1627 boot_ec->handle = ec->handle; 1628 acpi_handle_debug(ec->handle, "duplicated.\n"); 1629 acpi_ec_free(ec); 1630 ec = boot_ec; 1631 } 1632 } 1633 1634 ret = acpi_ec_setup(ec, device); 1635 if (ret) 1636 goto err; 1637 1638 if (ec == boot_ec) 1639 acpi_handle_info(boot_ec->handle, 1640 "Boot %s EC initialization complete\n", 1641 boot_ec_is_ecdt ? "ECDT" : "DSDT"); 1642 1643 acpi_handle_info(ec->handle, 1644 "EC: Used to handle transactions and events\n"); 1645 1646 device->driver_data = ec; 1647 1648 ret = !!request_region(ec->data_addr, 1, "EC data"); 1649 WARN(!ret, "Could not request EC data io port 0x%lx", ec->data_addr); 1650 ret = !!request_region(ec->command_addr, 1, "EC cmd"); 1651 WARN(!ret, "Could not request EC cmd io port 0x%lx", ec->command_addr); 1652 1653 /* Reprobe devices depending on the EC */ 1654 acpi_walk_dep_device_list(ec->handle); 1655 1656 acpi_handle_debug(ec->handle, "enumerated.\n"); 1657 return 0; 1658 1659err: 1660 if (ec != boot_ec) 1661 acpi_ec_free(ec); 1662 1663 return ret; 1664} 1665 1666static int acpi_ec_remove(struct acpi_device *device) 1667{ 1668 struct acpi_ec *ec; 1669 1670 if (!device) 1671 return -EINVAL; 1672 1673 ec = acpi_driver_data(device); 1674 release_region(ec->data_addr, 1); 1675 release_region(ec->command_addr, 1); 1676 device->driver_data = NULL; 1677 if (ec != boot_ec) { 1678 ec_remove_handlers(ec); 1679 acpi_ec_free(ec); 1680 } 1681 return 0; 1682} 1683 1684static acpi_status 1685ec_parse_io_ports(struct acpi_resource *resource, void *context) 1686{ 1687 struct acpi_ec *ec = context; 1688 1689 if (resource->type != ACPI_RESOURCE_TYPE_IO) 1690 return AE_OK; 1691 1692 /* 1693 * The first address region returned is the data port, and 1694 * the second address region returned is the status/command 1695 * port. 1696 */ 1697 if (ec->data_addr == 0) 1698 ec->data_addr = resource->data.io.minimum; 1699 else if (ec->command_addr == 0) 1700 ec->command_addr = resource->data.io.minimum; 1701 else 1702 return AE_CTRL_TERMINATE; 1703 1704 return AE_OK; 1705} 1706 1707static const struct acpi_device_id ec_device_ids[] = { 1708 {"PNP0C09", 0}, 1709 {ACPI_ECDT_HID, 0}, 1710 {"", 0}, 1711}; 1712 1713/* 1714 * This function is not Windows-compatible as Windows never enumerates the 1715 * namespace EC before the main ACPI device enumeration process. It is 1716 * retained for historical reason and will be deprecated in the future. 1717 */ 1718void __init acpi_ec_dsdt_probe(void) 1719{ 1720 struct acpi_ec *ec; 1721 acpi_status status; 1722 int ret; 1723 1724 /* 1725 * If a platform has ECDT, there is no need to proceed as the 1726 * following probe is not a part of the ACPI device enumeration, 1727 * executing _STA is not safe, and thus this probe may risk of 1728 * picking up an invalid EC device. 1729 */ 1730 if (boot_ec) 1731 return; 1732 1733 ec = acpi_ec_alloc(); 1734 if (!ec) 1735 return; 1736 1737 /* 1738 * At this point, the namespace is initialized, so start to find 1739 * the namespace objects. 1740 */ 1741 status = acpi_get_devices(ec_device_ids[0].id, ec_parse_device, ec, NULL); 1742 if (ACPI_FAILURE(status) || !ec->handle) { 1743 acpi_ec_free(ec); 1744 return; 1745 } 1746 1747 /* 1748 * When the DSDT EC is available, always re-configure boot EC to 1749 * have _REG evaluated. _REG can only be evaluated after the 1750 * namespace initialization. 1751 * At this point, the GPE is not fully initialized, so do not to 1752 * handle the events. 1753 */ 1754 ret = acpi_ec_setup(ec, NULL); 1755 if (ret) { 1756 acpi_ec_free(ec); 1757 return; 1758 } 1759 1760 boot_ec = ec; 1761 1762 acpi_handle_info(ec->handle, 1763 "Boot DSDT EC used to handle transactions\n"); 1764} 1765 1766/* 1767 * acpi_ec_ecdt_start - Finalize the boot ECDT EC initialization. 1768 * 1769 * First, look for an ACPI handle for the boot ECDT EC if acpi_ec_add() has not 1770 * found a matching object in the namespace. 1771 * 1772 * Next, in case the DSDT EC is not functioning, it is still necessary to 1773 * provide a functional ECDT EC to handle events, so add an extra device object 1774 * to represent it (see https://bugzilla.kernel.org/show_bug.cgi?id=115021). 1775 * 1776 * This is useful on platforms with valid ECDT and invalid DSDT EC settings, 1777 * like ASUS X550ZE (see https://bugzilla.kernel.org/show_bug.cgi?id=196847). 1778 */ 1779static void __init acpi_ec_ecdt_start(void) 1780{ 1781 struct acpi_table_ecdt *ecdt_ptr; 1782 acpi_handle handle; 1783 acpi_status status; 1784 1785 /* Bail out if a matching EC has been found in the namespace. */ 1786 if (!boot_ec || boot_ec->handle != ACPI_ROOT_OBJECT) 1787 return; 1788 1789 /* Look up the object pointed to from the ECDT in the namespace. */ 1790 status = acpi_get_table(ACPI_SIG_ECDT, 1, 1791 (struct acpi_table_header **)&ecdt_ptr); 1792 if (ACPI_FAILURE(status)) 1793 return; 1794 1795 status = acpi_get_handle(NULL, ecdt_ptr->id, &handle); 1796 if (ACPI_SUCCESS(status)) { 1797 boot_ec->handle = handle; 1798 1799 /* Add a special ACPI device object to represent the boot EC. */ 1800 acpi_bus_register_early_device(ACPI_BUS_TYPE_ECDT_EC); 1801 } 1802 1803 acpi_put_table((struct acpi_table_header *)ecdt_ptr); 1804} 1805 1806/* 1807 * On some hardware it is necessary to clear events accumulated by the EC during 1808 * sleep. These ECs stop reporting GPEs until they are manually polled, if too 1809 * many events are accumulated. (e.g. Samsung Series 5/9 notebooks) 1810 * 1811 * https://bugzilla.kernel.org/show_bug.cgi?id=44161 1812 * 1813 * Ideally, the EC should also be instructed NOT to accumulate events during 1814 * sleep (which Windows seems to do somehow), but the interface to control this 1815 * behaviour is not known at this time. 1816 * 1817 * Models known to be affected are Samsung 530Uxx/535Uxx/540Uxx/550Pxx/900Xxx, 1818 * however it is very likely that other Samsung models are affected. 1819 * 1820 * On systems which don't accumulate _Q events during sleep, this extra check 1821 * should be harmless. 1822 */ 1823static int ec_clear_on_resume(const struct dmi_system_id *id) 1824{ 1825 pr_debug("Detected system needing EC poll on resume.\n"); 1826 EC_FLAGS_CLEAR_ON_RESUME = 1; 1827 ec_event_clearing = ACPI_EC_EVT_TIMING_STATUS; 1828 return 0; 1829} 1830 1831/* 1832 * Some ECDTs contain wrong register addresses. 1833 * MSI MS-171F 1834 * https://bugzilla.kernel.org/show_bug.cgi?id=12461 1835 */ 1836static int ec_correct_ecdt(const struct dmi_system_id *id) 1837{ 1838 pr_debug("Detected system needing ECDT address correction.\n"); 1839 EC_FLAGS_CORRECT_ECDT = 1; 1840 return 0; 1841} 1842 1843/* 1844 * Some ECDTs contain wrong GPE setting, but they share the same port addresses 1845 * with DSDT EC, don't duplicate the DSDT EC with ECDT EC in this case. 1846 * https://bugzilla.kernel.org/show_bug.cgi?id=209989 1847 */ 1848static int ec_honor_dsdt_gpe(const struct dmi_system_id *id) 1849{ 1850 pr_debug("Detected system needing DSDT GPE setting.\n"); 1851 EC_FLAGS_TRUST_DSDT_GPE = 1; 1852 return 0; 1853} 1854 1855static const struct dmi_system_id ec_dmi_table[] __initconst = { 1856 { 1857 ec_correct_ecdt, "MSI MS-171F", { 1858 DMI_MATCH(DMI_SYS_VENDOR, "Micro-Star"), 1859 DMI_MATCH(DMI_PRODUCT_NAME, "MS-171F"),}, NULL}, 1860 { 1861 /* https://bugzilla.kernel.org/show_bug.cgi?id=209989 */ 1862 ec_honor_dsdt_gpe, "HP Pavilion Gaming Laptop 15-cx0xxx", { 1863 DMI_MATCH(DMI_SYS_VENDOR, "HP"), 1864 DMI_MATCH(DMI_PRODUCT_NAME, "HP Pavilion Gaming Laptop 15-cx0xxx"),}, NULL}, 1865 { 1866 ec_clear_on_resume, "Samsung hardware", { 1867 DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD.")}, NULL}, 1868 {}, 1869}; 1870 1871void __init acpi_ec_ecdt_probe(void) 1872{ 1873 struct acpi_table_ecdt *ecdt_ptr; 1874 struct acpi_ec *ec; 1875 acpi_status status; 1876 int ret; 1877 1878 /* Generate a boot ec context. */ 1879 dmi_check_system(ec_dmi_table); 1880 status = acpi_get_table(ACPI_SIG_ECDT, 1, 1881 (struct acpi_table_header **)&ecdt_ptr); 1882 if (ACPI_FAILURE(status)) 1883 return; 1884 1885 if (!ecdt_ptr->control.address || !ecdt_ptr->data.address) { 1886 /* 1887 * Asus X50GL: 1888 * https://bugzilla.kernel.org/show_bug.cgi?id=11880 1889 */ 1890 goto out; 1891 } 1892 1893 ec = acpi_ec_alloc(); 1894 if (!ec) 1895 goto out; 1896 1897 if (EC_FLAGS_CORRECT_ECDT) { 1898 ec->command_addr = ecdt_ptr->data.address; 1899 ec->data_addr = ecdt_ptr->control.address; 1900 } else { 1901 ec->command_addr = ecdt_ptr->control.address; 1902 ec->data_addr = ecdt_ptr->data.address; 1903 } 1904 1905 /* 1906 * Ignore the GPE value on Reduced Hardware platforms. 1907 * Some products have this set to an erroneous value. 1908 */ 1909 if (!acpi_gbl_reduced_hardware) 1910 ec->gpe = ecdt_ptr->gpe; 1911 1912 ec->handle = ACPI_ROOT_OBJECT; 1913 1914 /* 1915 * At this point, the namespace is not initialized, so do not find 1916 * the namespace objects, or handle the events. 1917 */ 1918 ret = acpi_ec_setup(ec, NULL); 1919 if (ret) { 1920 acpi_ec_free(ec); 1921 goto out; 1922 } 1923 1924 boot_ec = ec; 1925 boot_ec_is_ecdt = true; 1926 1927 pr_info("Boot ECDT EC used to handle transactions\n"); 1928 1929out: 1930 acpi_put_table((struct acpi_table_header *)ecdt_ptr); 1931} 1932 1933#ifdef CONFIG_PM_SLEEP 1934static int acpi_ec_suspend(struct device *dev) 1935{ 1936 struct acpi_ec *ec = 1937 acpi_driver_data(to_acpi_device(dev)); 1938 1939 if (!pm_suspend_no_platform() && ec_freeze_events) 1940 acpi_ec_disable_event(ec); 1941 return 0; 1942} 1943 1944static int acpi_ec_suspend_noirq(struct device *dev) 1945{ 1946 struct acpi_ec *ec = acpi_driver_data(to_acpi_device(dev)); 1947 1948 /* 1949 * The SCI handler doesn't run at this point, so the GPE can be 1950 * masked at the low level without side effects. 1951 */ 1952 if (ec_no_wakeup && test_bit(EC_FLAGS_STARTED, &ec->flags) && 1953 ec->gpe >= 0 && ec->reference_count >= 1) 1954 acpi_set_gpe(NULL, ec->gpe, ACPI_GPE_DISABLE); 1955 1956 acpi_ec_enter_noirq(ec); 1957 1958 return 0; 1959} 1960 1961static int acpi_ec_resume_noirq(struct device *dev) 1962{ 1963 struct acpi_ec *ec = acpi_driver_data(to_acpi_device(dev)); 1964 1965 acpi_ec_leave_noirq(ec); 1966 1967 if (ec_no_wakeup && test_bit(EC_FLAGS_STARTED, &ec->flags) && 1968 ec->gpe >= 0 && ec->reference_count >= 1) 1969 acpi_set_gpe(NULL, ec->gpe, ACPI_GPE_ENABLE); 1970 1971 return 0; 1972} 1973 1974static int acpi_ec_resume(struct device *dev) 1975{ 1976 struct acpi_ec *ec = 1977 acpi_driver_data(to_acpi_device(dev)); 1978 1979 acpi_ec_enable_event(ec); 1980 return 0; 1981} 1982 1983void acpi_ec_mark_gpe_for_wake(void) 1984{ 1985 if (first_ec && !ec_no_wakeup) 1986 acpi_mark_gpe_for_wake(NULL, first_ec->gpe); 1987} 1988EXPORT_SYMBOL_GPL(acpi_ec_mark_gpe_for_wake); 1989 1990void acpi_ec_set_gpe_wake_mask(u8 action) 1991{ 1992 if (pm_suspend_no_platform() && first_ec && !ec_no_wakeup) 1993 acpi_set_gpe_wake_mask(NULL, first_ec->gpe, action); 1994} 1995 1996bool acpi_ec_dispatch_gpe(void) 1997{ 1998 bool work_in_progress; 1999 u32 ret; 2000 2001 if (!first_ec) 2002 return acpi_any_gpe_status_set(U32_MAX); 2003 2004 /* 2005 * Report wakeup if the status bit is set for any enabled GPE other 2006 * than the EC one. 2007 */ 2008 if (acpi_any_gpe_status_set(first_ec->gpe)) 2009 return true; 2010 2011 /* 2012 * Dispatch the EC GPE in-band, but do not report wakeup in any case 2013 * to allow the caller to process events properly after that. 2014 */ 2015 ret = acpi_dispatch_gpe(NULL, first_ec->gpe); 2016 if (ret == ACPI_INTERRUPT_HANDLED) 2017 pm_pr_dbg("ACPI EC GPE dispatched\n"); 2018 2019 /* Drain EC work. */ 2020 do { 2021 acpi_ec_flush_work(); 2022 2023 pm_pr_dbg("ACPI EC work flushed\n"); 2024 2025 spin_lock_irq(&first_ec->lock); 2026 2027 work_in_progress = first_ec->events_in_progress + 2028 first_ec->queries_in_progress > 0; 2029 2030 spin_unlock_irq(&first_ec->lock); 2031 } while (work_in_progress && !pm_wakeup_pending()); 2032 2033 return false; 2034} 2035#endif /* CONFIG_PM_SLEEP */ 2036 2037static const struct dev_pm_ops acpi_ec_pm = { 2038 SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(acpi_ec_suspend_noirq, acpi_ec_resume_noirq) 2039 SET_SYSTEM_SLEEP_PM_OPS(acpi_ec_suspend, acpi_ec_resume) 2040}; 2041 2042static int param_set_event_clearing(const char *val, 2043 const struct kernel_param *kp) 2044{ 2045 int result = 0; 2046 2047 if (!strncmp(val, "status", sizeof("status") - 1)) { 2048 ec_event_clearing = ACPI_EC_EVT_TIMING_STATUS; 2049 pr_info("Assuming SCI_EVT clearing on EC_SC accesses\n"); 2050 } else if (!strncmp(val, "query", sizeof("query") - 1)) { 2051 ec_event_clearing = ACPI_EC_EVT_TIMING_QUERY; 2052 pr_info("Assuming SCI_EVT clearing on QR_EC writes\n"); 2053 } else if (!strncmp(val, "event", sizeof("event") - 1)) { 2054 ec_event_clearing = ACPI_EC_EVT_TIMING_EVENT; 2055 pr_info("Assuming SCI_EVT clearing on event reads\n"); 2056 } else 2057 result = -EINVAL; 2058 return result; 2059} 2060 2061static int param_get_event_clearing(char *buffer, 2062 const struct kernel_param *kp) 2063{ 2064 switch (ec_event_clearing) { 2065 case ACPI_EC_EVT_TIMING_STATUS: 2066 return sprintf(buffer, "status\n"); 2067 case ACPI_EC_EVT_TIMING_QUERY: 2068 return sprintf(buffer, "query\n"); 2069 case ACPI_EC_EVT_TIMING_EVENT: 2070 return sprintf(buffer, "event\n"); 2071 default: 2072 return sprintf(buffer, "invalid\n"); 2073 } 2074 return 0; 2075} 2076 2077module_param_call(ec_event_clearing, param_set_event_clearing, param_get_event_clearing, 2078 NULL, 0644); 2079MODULE_PARM_DESC(ec_event_clearing, "Assumed SCI_EVT clearing timing"); 2080 2081static struct acpi_driver acpi_ec_driver = { 2082 .name = "ec", 2083 .class = ACPI_EC_CLASS, 2084 .ids = ec_device_ids, 2085 .ops = { 2086 .add = acpi_ec_add, 2087 .remove = acpi_ec_remove, 2088 }, 2089 .drv.pm = &acpi_ec_pm, 2090}; 2091 2092static void acpi_ec_destroy_workqueues(void) 2093{ 2094 if (ec_wq) { 2095 destroy_workqueue(ec_wq); 2096 ec_wq = NULL; 2097 } 2098 if (ec_query_wq) { 2099 destroy_workqueue(ec_query_wq); 2100 ec_query_wq = NULL; 2101 } 2102} 2103 2104static int acpi_ec_init_workqueues(void) 2105{ 2106 if (!ec_wq) 2107 ec_wq = alloc_ordered_workqueue("kec", 0); 2108 2109 if (!ec_query_wq) 2110 ec_query_wq = alloc_workqueue("kec_query", 0, ec_max_queries); 2111 2112 if (!ec_wq || !ec_query_wq) { 2113 acpi_ec_destroy_workqueues(); 2114 return -ENODEV; 2115 } 2116 return 0; 2117} 2118 2119static const struct dmi_system_id acpi_ec_no_wakeup[] = { 2120 { 2121 .ident = "Thinkpad X1 Carbon 6th", 2122 .matches = { 2123 DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"), 2124 DMI_MATCH(DMI_PRODUCT_FAMILY, "Thinkpad X1 Carbon 6th"), 2125 }, 2126 }, 2127 { 2128 .ident = "ThinkPad X1 Yoga 3rd", 2129 .matches = { 2130 DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"), 2131 DMI_MATCH(DMI_PRODUCT_FAMILY, "ThinkPad X1 Yoga 3rd"), 2132 }, 2133 }, 2134 { }, 2135}; 2136 2137void __init acpi_ec_init(void) 2138{ 2139 int result; 2140 2141 result = acpi_ec_init_workqueues(); 2142 if (result) 2143 return; 2144 2145 /* 2146 * Disable EC wakeup on following systems to prevent periodic 2147 * wakeup from EC GPE. 2148 */ 2149 if (dmi_check_system(acpi_ec_no_wakeup)) { 2150 ec_no_wakeup = true; 2151 pr_debug("Disabling EC wakeup on suspend-to-idle\n"); 2152 } 2153 2154 /* Driver must be registered after acpi_ec_init_workqueues(). */ 2155 acpi_bus_register_driver(&acpi_ec_driver); 2156 2157 acpi_ec_ecdt_start(); 2158} 2159 2160/* EC driver currently not unloadable */ 2161#if 0 2162static void __exit acpi_ec_exit(void) 2163{ 2164 2165 acpi_bus_unregister_driver(&acpi_ec_driver); 2166 acpi_ec_destroy_workqueues(); 2167} 2168#endif /* 0 */ 2169