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 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 26 */ 27 28 /* Uncomment next line to get verbose printout */ 29 /* #define DEBUG */ 30 #define pr_fmt(fmt) "ACPI: EC: " fmt 31 32 #include <linux/kernel.h> 33 #include <linux/module.h> 34 #include <linux/init.h> 35 #include <linux/types.h> 36 #include <linux/delay.h> 37 #include <linux/interrupt.h> 38 #include <linux/list.h> 39 #include <linux/spinlock.h> 40 #include <linux/slab.h> 41 #include <linux/acpi.h> 42 #include <linux/dmi.h> 43 #include <asm/io.h> 44 45 #include "internal.h" 46 47 #define ACPI_EC_CLASS "embedded_controller" 48 #define ACPI_EC_DEVICE_NAME "Embedded Controller" 49 #define ACPI_EC_FILE_INFO "info" 50 51 /* EC status register */ 52 #define ACPI_EC_FLAG_OBF 0x01 /* Output buffer full */ 53 #define ACPI_EC_FLAG_IBF 0x02 /* Input buffer full */ 54 #define ACPI_EC_FLAG_CMD 0x08 /* Input buffer contains a command */ 55 #define ACPI_EC_FLAG_BURST 0x10 /* burst mode */ 56 #define ACPI_EC_FLAG_SCI 0x20 /* EC-SCI occurred */ 57 58 /* 59 * The SCI_EVT clearing timing is not defined by the ACPI specification. 60 * This leads to lots of practical timing issues for the host EC driver. 61 * The following variations are defined (from the target EC firmware's 62 * perspective): 63 * STATUS: After indicating SCI_EVT edge triggered IRQ to the host, the 64 * target can clear SCI_EVT at any time so long as the host can see 65 * the indication by reading the status register (EC_SC). So the 66 * host should re-check SCI_EVT after the first time the SCI_EVT 67 * indication is seen, which is the same time the query request 68 * (QR_EC) is written to the command register (EC_CMD). SCI_EVT set 69 * at any later time could indicate another event. Normally such 70 * kind of EC firmware has implemented an event queue and will 71 * return 0x00 to indicate "no outstanding event". 72 * QUERY: After seeing the query request (QR_EC) written to the command 73 * register (EC_CMD) by the host and having prepared the responding 74 * event value in the data register (EC_DATA), the target can safely 75 * clear SCI_EVT because the target can confirm that the current 76 * event is being handled by the host. The host then should check 77 * SCI_EVT right after reading the event response from the data 78 * register (EC_DATA). 79 * EVENT: After seeing the event response read from the data register 80 * (EC_DATA) by the host, the target can clear SCI_EVT. As the 81 * target requires time to notice the change in the data register 82 * (EC_DATA), the host may be required to wait additional guarding 83 * time before checking the SCI_EVT again. Such guarding may not be 84 * necessary if the host is notified via another IRQ. 85 */ 86 #define ACPI_EC_EVT_TIMING_STATUS 0x00 87 #define ACPI_EC_EVT_TIMING_QUERY 0x01 88 #define ACPI_EC_EVT_TIMING_EVENT 0x02 89 90 /* EC commands */ 91 enum ec_command { 92 ACPI_EC_COMMAND_READ = 0x80, 93 ACPI_EC_COMMAND_WRITE = 0x81, 94 ACPI_EC_BURST_ENABLE = 0x82, 95 ACPI_EC_BURST_DISABLE = 0x83, 96 ACPI_EC_COMMAND_QUERY = 0x84, 97 }; 98 99 #define ACPI_EC_DELAY 500 /* Wait 500ms max. during EC ops */ 100 #define ACPI_EC_UDELAY_GLK 1000 /* Wait 1ms max. to get global lock */ 101 #define ACPI_EC_UDELAY_POLL 550 /* Wait 1ms for EC transaction polling */ 102 #define ACPI_EC_CLEAR_MAX 100 /* Maximum number of events to query 103 * when trying to clear the EC */ 104 #define ACPI_EC_MAX_QUERIES 16 /* Maximum number of parallel queries */ 105 106 enum { 107 EC_FLAGS_QUERY_ENABLED, /* Query is enabled */ 108 EC_FLAGS_QUERY_PENDING, /* Query is pending */ 109 EC_FLAGS_QUERY_GUARDING, /* Guard for SCI_EVT check */ 110 EC_FLAGS_GPE_HANDLER_INSTALLED, /* GPE handler installed */ 111 EC_FLAGS_EC_HANDLER_INSTALLED, /* OpReg handler installed */ 112 EC_FLAGS_EVT_HANDLER_INSTALLED, /* _Qxx handlers installed */ 113 EC_FLAGS_STARTED, /* Driver is started */ 114 EC_FLAGS_STOPPED, /* Driver is stopped */ 115 EC_FLAGS_COMMAND_STORM, /* GPE storms occurred to the 116 * current command processing */ 117 }; 118 119 #define ACPI_EC_COMMAND_POLL 0x01 /* Available for command byte */ 120 #define ACPI_EC_COMMAND_COMPLETE 0x02 /* Completed last byte */ 121 122 /* ec.c is compiled in acpi namespace so this shows up as acpi.ec_delay param */ 123 static unsigned int ec_delay __read_mostly = ACPI_EC_DELAY; 124 module_param(ec_delay, uint, 0644); 125 MODULE_PARM_DESC(ec_delay, "Timeout(ms) waited until an EC command completes"); 126 127 static unsigned int ec_max_queries __read_mostly = ACPI_EC_MAX_QUERIES; 128 module_param(ec_max_queries, uint, 0644); 129 MODULE_PARM_DESC(ec_max_queries, "Maximum parallel _Qxx evaluations"); 130 131 static bool ec_busy_polling __read_mostly; 132 module_param(ec_busy_polling, bool, 0644); 133 MODULE_PARM_DESC(ec_busy_polling, "Use busy polling to advance EC transaction"); 134 135 static unsigned int ec_polling_guard __read_mostly = ACPI_EC_UDELAY_POLL; 136 module_param(ec_polling_guard, uint, 0644); 137 MODULE_PARM_DESC(ec_polling_guard, "Guard time(us) between EC accesses in polling modes"); 138 139 static unsigned int ec_event_clearing __read_mostly = ACPI_EC_EVT_TIMING_QUERY; 140 141 /* 142 * If the number of false interrupts per one transaction exceeds 143 * this threshold, will think there is a GPE storm happened and 144 * will disable the GPE for normal transaction. 145 */ 146 static unsigned int ec_storm_threshold __read_mostly = 8; 147 module_param(ec_storm_threshold, uint, 0644); 148 MODULE_PARM_DESC(ec_storm_threshold, "Maxim false GPE numbers not considered as GPE storm"); 149 150 static bool ec_freeze_events __read_mostly = false; 151 module_param(ec_freeze_events, bool, 0644); 152 MODULE_PARM_DESC(ec_freeze_events, "Disabling event handling during suspend/resume"); 153 154 static bool ec_no_wakeup __read_mostly; 155 module_param(ec_no_wakeup, bool, 0644); 156 MODULE_PARM_DESC(ec_no_wakeup, "Do not wake up from suspend-to-idle"); 157 158 struct acpi_ec_query_handler { 159 struct list_head node; 160 acpi_ec_query_func func; 161 acpi_handle handle; 162 void *data; 163 u8 query_bit; 164 struct kref kref; 165 }; 166 167 struct transaction { 168 const u8 *wdata; 169 u8 *rdata; 170 unsigned short irq_count; 171 u8 command; 172 u8 wi; 173 u8 ri; 174 u8 wlen; 175 u8 rlen; 176 u8 flags; 177 }; 178 179 struct acpi_ec_query { 180 struct transaction transaction; 181 struct work_struct work; 182 struct acpi_ec_query_handler *handler; 183 }; 184 185 static int acpi_ec_query(struct acpi_ec *ec, u8 *data); 186 static void advance_transaction(struct acpi_ec *ec); 187 static void acpi_ec_event_handler(struct work_struct *work); 188 static void acpi_ec_event_processor(struct work_struct *work); 189 190 struct acpi_ec *boot_ec, *first_ec; 191 EXPORT_SYMBOL(first_ec); 192 static bool boot_ec_is_ecdt = false; 193 static struct workqueue_struct *ec_query_wq; 194 195 static int EC_FLAGS_QUERY_HANDSHAKE; /* Needs QR_EC issued when SCI_EVT set */ 196 static int EC_FLAGS_CORRECT_ECDT; /* Needs ECDT port address correction */ 197 static int EC_FLAGS_IGNORE_DSDT_GPE; /* Needs ECDT GPE as correction setting */ 198 199 /* -------------------------------------------------------------------------- 200 * Logging/Debugging 201 * -------------------------------------------------------------------------- */ 202 203 /* 204 * Splitters used by the developers to track the boundary of the EC 205 * handling processes. 206 */ 207 #ifdef DEBUG 208 #define EC_DBG_SEP " " 209 #define EC_DBG_DRV "+++++" 210 #define EC_DBG_STM "=====" 211 #define EC_DBG_REQ "*****" 212 #define EC_DBG_EVT "#####" 213 #else 214 #define EC_DBG_SEP "" 215 #define EC_DBG_DRV 216 #define EC_DBG_STM 217 #define EC_DBG_REQ 218 #define EC_DBG_EVT 219 #endif 220 221 #define ec_log_raw(fmt, ...) \ 222 pr_info(fmt "\n", ##__VA_ARGS__) 223 #define ec_dbg_raw(fmt, ...) \ 224 pr_debug(fmt "\n", ##__VA_ARGS__) 225 #define ec_log(filter, fmt, ...) \ 226 ec_log_raw(filter EC_DBG_SEP fmt EC_DBG_SEP filter, ##__VA_ARGS__) 227 #define ec_dbg(filter, fmt, ...) \ 228 ec_dbg_raw(filter EC_DBG_SEP fmt EC_DBG_SEP filter, ##__VA_ARGS__) 229 230 #define ec_log_drv(fmt, ...) \ 231 ec_log(EC_DBG_DRV, fmt, ##__VA_ARGS__) 232 #define ec_dbg_drv(fmt, ...) \ 233 ec_dbg(EC_DBG_DRV, fmt, ##__VA_ARGS__) 234 #define ec_dbg_stm(fmt, ...) \ 235 ec_dbg(EC_DBG_STM, fmt, ##__VA_ARGS__) 236 #define ec_dbg_req(fmt, ...) \ 237 ec_dbg(EC_DBG_REQ, fmt, ##__VA_ARGS__) 238 #define ec_dbg_evt(fmt, ...) \ 239 ec_dbg(EC_DBG_EVT, fmt, ##__VA_ARGS__) 240 #define ec_dbg_ref(ec, fmt, ...) \ 241 ec_dbg_raw("%lu: " fmt, ec->reference_count, ## __VA_ARGS__) 242 243 /* -------------------------------------------------------------------------- 244 * Device Flags 245 * -------------------------------------------------------------------------- */ 246 247 static bool acpi_ec_started(struct acpi_ec *ec) 248 { 249 return test_bit(EC_FLAGS_STARTED, &ec->flags) && 250 !test_bit(EC_FLAGS_STOPPED, &ec->flags); 251 } 252 253 static bool acpi_ec_event_enabled(struct acpi_ec *ec) 254 { 255 /* 256 * There is an OSPM early stage logic. During the early stages 257 * (boot/resume), OSPMs shouldn't enable the event handling, only 258 * the EC transactions are allowed to be performed. 259 */ 260 if (!test_bit(EC_FLAGS_QUERY_ENABLED, &ec->flags)) 261 return false; 262 /* 263 * However, disabling the event handling is experimental for late 264 * stage (suspend), and is controlled by the boot parameter of 265 * "ec_freeze_events": 266 * 1. true: The EC event handling is disabled before entering 267 * the noirq stage. 268 * 2. false: The EC event handling is automatically disabled as 269 * soon as the EC driver is stopped. 270 */ 271 if (ec_freeze_events) 272 return acpi_ec_started(ec); 273 else 274 return test_bit(EC_FLAGS_STARTED, &ec->flags); 275 } 276 277 static bool acpi_ec_flushed(struct acpi_ec *ec) 278 { 279 return ec->reference_count == 1; 280 } 281 282 /* -------------------------------------------------------------------------- 283 * EC Registers 284 * -------------------------------------------------------------------------- */ 285 286 static inline u8 acpi_ec_read_status(struct acpi_ec *ec) 287 { 288 u8 x = inb(ec->command_addr); 289 290 ec_dbg_raw("EC_SC(R) = 0x%2.2x " 291 "SCI_EVT=%d BURST=%d CMD=%d IBF=%d OBF=%d", 292 x, 293 !!(x & ACPI_EC_FLAG_SCI), 294 !!(x & ACPI_EC_FLAG_BURST), 295 !!(x & ACPI_EC_FLAG_CMD), 296 !!(x & ACPI_EC_FLAG_IBF), 297 !!(x & ACPI_EC_FLAG_OBF)); 298 return x; 299 } 300 301 static inline u8 acpi_ec_read_data(struct acpi_ec *ec) 302 { 303 u8 x = inb(ec->data_addr); 304 305 ec->timestamp = jiffies; 306 ec_dbg_raw("EC_DATA(R) = 0x%2.2x", x); 307 return x; 308 } 309 310 static inline void acpi_ec_write_cmd(struct acpi_ec *ec, u8 command) 311 { 312 ec_dbg_raw("EC_SC(W) = 0x%2.2x", command); 313 outb(command, ec->command_addr); 314 ec->timestamp = jiffies; 315 } 316 317 static inline void acpi_ec_write_data(struct acpi_ec *ec, u8 data) 318 { 319 ec_dbg_raw("EC_DATA(W) = 0x%2.2x", data); 320 outb(data, ec->data_addr); 321 ec->timestamp = jiffies; 322 } 323 324 #if defined(DEBUG) || defined(CONFIG_DYNAMIC_DEBUG) 325 static const char *acpi_ec_cmd_string(u8 cmd) 326 { 327 switch (cmd) { 328 case 0x80: 329 return "RD_EC"; 330 case 0x81: 331 return "WR_EC"; 332 case 0x82: 333 return "BE_EC"; 334 case 0x83: 335 return "BD_EC"; 336 case 0x84: 337 return "QR_EC"; 338 } 339 return "UNKNOWN"; 340 } 341 #else 342 #define acpi_ec_cmd_string(cmd) "UNDEF" 343 #endif 344 345 /* -------------------------------------------------------------------------- 346 * GPE Registers 347 * -------------------------------------------------------------------------- */ 348 349 static inline bool acpi_ec_is_gpe_raised(struct acpi_ec *ec) 350 { 351 acpi_event_status gpe_status = 0; 352 353 (void)acpi_get_gpe_status(NULL, ec->gpe, &gpe_status); 354 return (gpe_status & ACPI_EVENT_FLAG_STATUS_SET) ? true : false; 355 } 356 357 static inline void acpi_ec_enable_gpe(struct acpi_ec *ec, bool open) 358 { 359 if (open) 360 acpi_enable_gpe(NULL, ec->gpe); 361 else { 362 BUG_ON(ec->reference_count < 1); 363 acpi_set_gpe(NULL, ec->gpe, ACPI_GPE_ENABLE); 364 } 365 if (acpi_ec_is_gpe_raised(ec)) { 366 /* 367 * On some platforms, EN=1 writes cannot trigger GPE. So 368 * software need to manually trigger a pseudo GPE event on 369 * EN=1 writes. 370 */ 371 ec_dbg_raw("Polling quirk"); 372 advance_transaction(ec); 373 } 374 } 375 376 static inline void acpi_ec_disable_gpe(struct acpi_ec *ec, bool close) 377 { 378 if (close) 379 acpi_disable_gpe(NULL, ec->gpe); 380 else { 381 BUG_ON(ec->reference_count < 1); 382 acpi_set_gpe(NULL, ec->gpe, ACPI_GPE_DISABLE); 383 } 384 } 385 386 static inline void acpi_ec_clear_gpe(struct acpi_ec *ec) 387 { 388 /* 389 * GPE STS is a W1C register, which means: 390 * 1. Software can clear it without worrying about clearing other 391 * GPEs' STS bits when the hardware sets them in parallel. 392 * 2. As long as software can ensure only clearing it when it is 393 * set, hardware won't set it in parallel. 394 * So software can clear GPE in any contexts. 395 * Warning: do not move the check into advance_transaction() as the 396 * EC commands will be sent without GPE raised. 397 */ 398 if (!acpi_ec_is_gpe_raised(ec)) 399 return; 400 acpi_clear_gpe(NULL, ec->gpe); 401 } 402 403 /* -------------------------------------------------------------------------- 404 * Transaction Management 405 * -------------------------------------------------------------------------- */ 406 407 static void acpi_ec_submit_request(struct acpi_ec *ec) 408 { 409 ec->reference_count++; 410 if (test_bit(EC_FLAGS_GPE_HANDLER_INSTALLED, &ec->flags) && 411 ec->reference_count == 1) 412 acpi_ec_enable_gpe(ec, true); 413 } 414 415 static void acpi_ec_complete_request(struct acpi_ec *ec) 416 { 417 bool flushed = false; 418 419 ec->reference_count--; 420 if (test_bit(EC_FLAGS_GPE_HANDLER_INSTALLED, &ec->flags) && 421 ec->reference_count == 0) 422 acpi_ec_disable_gpe(ec, true); 423 flushed = acpi_ec_flushed(ec); 424 if (flushed) 425 wake_up(&ec->wait); 426 } 427 428 static void acpi_ec_set_storm(struct acpi_ec *ec, u8 flag) 429 { 430 if (!test_bit(flag, &ec->flags)) { 431 acpi_ec_disable_gpe(ec, false); 432 ec_dbg_drv("Polling enabled"); 433 set_bit(flag, &ec->flags); 434 } 435 } 436 437 static void acpi_ec_clear_storm(struct acpi_ec *ec, u8 flag) 438 { 439 if (test_bit(flag, &ec->flags)) { 440 clear_bit(flag, &ec->flags); 441 acpi_ec_enable_gpe(ec, false); 442 ec_dbg_drv("Polling disabled"); 443 } 444 } 445 446 /* 447 * acpi_ec_submit_flushable_request() - Increase the reference count unless 448 * the flush operation is not in 449 * progress 450 * @ec: the EC device 451 * 452 * This function must be used before taking a new action that should hold 453 * the reference count. If this function returns false, then the action 454 * must be discarded or it will prevent the flush operation from being 455 * completed. 456 */ 457 static bool acpi_ec_submit_flushable_request(struct acpi_ec *ec) 458 { 459 if (!acpi_ec_started(ec)) 460 return false; 461 acpi_ec_submit_request(ec); 462 return true; 463 } 464 465 static void acpi_ec_submit_query(struct acpi_ec *ec) 466 { 467 acpi_ec_set_storm(ec, EC_FLAGS_COMMAND_STORM); 468 if (!acpi_ec_event_enabled(ec)) 469 return; 470 if (!test_and_set_bit(EC_FLAGS_QUERY_PENDING, &ec->flags)) { 471 ec_dbg_evt("Command(%s) submitted/blocked", 472 acpi_ec_cmd_string(ACPI_EC_COMMAND_QUERY)); 473 ec->nr_pending_queries++; 474 schedule_work(&ec->work); 475 } 476 } 477 478 static void acpi_ec_complete_query(struct acpi_ec *ec) 479 { 480 if (test_and_clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags)) 481 ec_dbg_evt("Command(%s) unblocked", 482 acpi_ec_cmd_string(ACPI_EC_COMMAND_QUERY)); 483 acpi_ec_clear_storm(ec, EC_FLAGS_COMMAND_STORM); 484 } 485 486 static inline void __acpi_ec_enable_event(struct acpi_ec *ec) 487 { 488 if (!test_and_set_bit(EC_FLAGS_QUERY_ENABLED, &ec->flags)) 489 ec_log_drv("event unblocked"); 490 if (!test_bit(EC_FLAGS_QUERY_PENDING, &ec->flags)) 491 advance_transaction(ec); 492 } 493 494 static inline void __acpi_ec_disable_event(struct acpi_ec *ec) 495 { 496 if (test_and_clear_bit(EC_FLAGS_QUERY_ENABLED, &ec->flags)) 497 ec_log_drv("event blocked"); 498 } 499 500 static void acpi_ec_enable_event(struct acpi_ec *ec) 501 { 502 unsigned long flags; 503 504 spin_lock_irqsave(&ec->lock, flags); 505 if (acpi_ec_started(ec)) 506 __acpi_ec_enable_event(ec); 507 spin_unlock_irqrestore(&ec->lock, flags); 508 } 509 510 #ifdef CONFIG_PM_SLEEP 511 static bool acpi_ec_query_flushed(struct acpi_ec *ec) 512 { 513 bool flushed; 514 unsigned long flags; 515 516 spin_lock_irqsave(&ec->lock, flags); 517 flushed = !ec->nr_pending_queries; 518 spin_unlock_irqrestore(&ec->lock, flags); 519 return flushed; 520 } 521 522 static void __acpi_ec_flush_event(struct acpi_ec *ec) 523 { 524 /* 525 * When ec_freeze_events is true, we need to flush events in 526 * the proper position before entering the noirq stage. 527 */ 528 wait_event(ec->wait, acpi_ec_query_flushed(ec)); 529 if (ec_query_wq) 530 flush_workqueue(ec_query_wq); 531 } 532 533 static void acpi_ec_disable_event(struct acpi_ec *ec) 534 { 535 unsigned long flags; 536 537 spin_lock_irqsave(&ec->lock, flags); 538 __acpi_ec_disable_event(ec); 539 spin_unlock_irqrestore(&ec->lock, flags); 540 __acpi_ec_flush_event(ec); 541 } 542 543 void acpi_ec_flush_work(void) 544 { 545 if (first_ec) 546 __acpi_ec_flush_event(first_ec); 547 548 flush_scheduled_work(); 549 } 550 #endif /* CONFIG_PM_SLEEP */ 551 552 static bool acpi_ec_guard_event(struct acpi_ec *ec) 553 { 554 bool guarded = true; 555 unsigned long flags; 556 557 spin_lock_irqsave(&ec->lock, flags); 558 /* 559 * If firmware SCI_EVT clearing timing is "event", we actually 560 * don't know when the SCI_EVT will be cleared by firmware after 561 * evaluating _Qxx, so we need to re-check SCI_EVT after waiting an 562 * acceptable period. 563 * 564 * The guarding period begins when EC_FLAGS_QUERY_PENDING is 565 * flagged, which means SCI_EVT check has just been performed. 566 * But if the current transaction is ACPI_EC_COMMAND_QUERY, the 567 * guarding should have already been performed (via 568 * EC_FLAGS_QUERY_GUARDING) and should not be applied so that the 569 * ACPI_EC_COMMAND_QUERY transaction can be transitioned into 570 * ACPI_EC_COMMAND_POLL state immediately. 571 */ 572 if (ec_event_clearing == ACPI_EC_EVT_TIMING_STATUS || 573 ec_event_clearing == ACPI_EC_EVT_TIMING_QUERY || 574 !test_bit(EC_FLAGS_QUERY_PENDING, &ec->flags) || 575 (ec->curr && ec->curr->command == ACPI_EC_COMMAND_QUERY)) 576 guarded = false; 577 spin_unlock_irqrestore(&ec->lock, flags); 578 return guarded; 579 } 580 581 static int ec_transaction_polled(struct acpi_ec *ec) 582 { 583 unsigned long flags; 584 int ret = 0; 585 586 spin_lock_irqsave(&ec->lock, flags); 587 if (ec->curr && (ec->curr->flags & ACPI_EC_COMMAND_POLL)) 588 ret = 1; 589 spin_unlock_irqrestore(&ec->lock, flags); 590 return ret; 591 } 592 593 static int ec_transaction_completed(struct acpi_ec *ec) 594 { 595 unsigned long flags; 596 int ret = 0; 597 598 spin_lock_irqsave(&ec->lock, flags); 599 if (ec->curr && (ec->curr->flags & ACPI_EC_COMMAND_COMPLETE)) 600 ret = 1; 601 spin_unlock_irqrestore(&ec->lock, flags); 602 return ret; 603 } 604 605 static inline void ec_transaction_transition(struct acpi_ec *ec, unsigned long flag) 606 { 607 ec->curr->flags |= flag; 608 if (ec->curr->command == ACPI_EC_COMMAND_QUERY) { 609 if (ec_event_clearing == ACPI_EC_EVT_TIMING_STATUS && 610 flag == ACPI_EC_COMMAND_POLL) 611 acpi_ec_complete_query(ec); 612 if (ec_event_clearing == ACPI_EC_EVT_TIMING_QUERY && 613 flag == ACPI_EC_COMMAND_COMPLETE) 614 acpi_ec_complete_query(ec); 615 if (ec_event_clearing == ACPI_EC_EVT_TIMING_EVENT && 616 flag == ACPI_EC_COMMAND_COMPLETE) 617 set_bit(EC_FLAGS_QUERY_GUARDING, &ec->flags); 618 } 619 } 620 621 static void advance_transaction(struct acpi_ec *ec) 622 { 623 struct transaction *t; 624 u8 status; 625 bool wakeup = false; 626 627 ec_dbg_stm("%s (%d)", in_interrupt() ? "IRQ" : "TASK", 628 smp_processor_id()); 629 /* 630 * By always clearing STS before handling all indications, we can 631 * ensure a hardware STS 0->1 change after this clearing can always 632 * trigger a GPE interrupt. 633 */ 634 acpi_ec_clear_gpe(ec); 635 status = acpi_ec_read_status(ec); 636 t = ec->curr; 637 /* 638 * Another IRQ or a guarded polling mode advancement is detected, 639 * the next QR_EC submission is then allowed. 640 */ 641 if (!t || !(t->flags & ACPI_EC_COMMAND_POLL)) { 642 if (ec_event_clearing == ACPI_EC_EVT_TIMING_EVENT && 643 (!ec->nr_pending_queries || 644 test_bit(EC_FLAGS_QUERY_GUARDING, &ec->flags))) { 645 clear_bit(EC_FLAGS_QUERY_GUARDING, &ec->flags); 646 acpi_ec_complete_query(ec); 647 } 648 } 649 if (!t) 650 goto err; 651 if (t->flags & ACPI_EC_COMMAND_POLL) { 652 if (t->wlen > t->wi) { 653 if ((status & ACPI_EC_FLAG_IBF) == 0) 654 acpi_ec_write_data(ec, t->wdata[t->wi++]); 655 else 656 goto err; 657 } else if (t->rlen > t->ri) { 658 if ((status & ACPI_EC_FLAG_OBF) == 1) { 659 t->rdata[t->ri++] = acpi_ec_read_data(ec); 660 if (t->rlen == t->ri) { 661 ec_transaction_transition(ec, ACPI_EC_COMMAND_COMPLETE); 662 if (t->command == ACPI_EC_COMMAND_QUERY) 663 ec_dbg_evt("Command(%s) completed by hardware", 664 acpi_ec_cmd_string(ACPI_EC_COMMAND_QUERY)); 665 wakeup = true; 666 } 667 } else 668 goto err; 669 } else if (t->wlen == t->wi && 670 (status & ACPI_EC_FLAG_IBF) == 0) { 671 ec_transaction_transition(ec, ACPI_EC_COMMAND_COMPLETE); 672 wakeup = true; 673 } 674 goto out; 675 } else { 676 if (EC_FLAGS_QUERY_HANDSHAKE && 677 !(status & ACPI_EC_FLAG_SCI) && 678 (t->command == ACPI_EC_COMMAND_QUERY)) { 679 ec_transaction_transition(ec, ACPI_EC_COMMAND_POLL); 680 t->rdata[t->ri++] = 0x00; 681 ec_transaction_transition(ec, ACPI_EC_COMMAND_COMPLETE); 682 ec_dbg_evt("Command(%s) completed by software", 683 acpi_ec_cmd_string(ACPI_EC_COMMAND_QUERY)); 684 wakeup = true; 685 } else if ((status & ACPI_EC_FLAG_IBF) == 0) { 686 acpi_ec_write_cmd(ec, t->command); 687 ec_transaction_transition(ec, ACPI_EC_COMMAND_POLL); 688 } else 689 goto err; 690 goto out; 691 } 692 err: 693 /* 694 * If SCI bit is set, then don't think it's a false IRQ 695 * otherwise will take a not handled IRQ as a false one. 696 */ 697 if (!(status & ACPI_EC_FLAG_SCI)) { 698 if (in_interrupt() && t) { 699 if (t->irq_count < ec_storm_threshold) 700 ++t->irq_count; 701 /* Allow triggering on 0 threshold */ 702 if (t->irq_count == ec_storm_threshold) 703 acpi_ec_set_storm(ec, EC_FLAGS_COMMAND_STORM); 704 } 705 } 706 out: 707 if (status & ACPI_EC_FLAG_SCI) 708 acpi_ec_submit_query(ec); 709 if (wakeup && in_interrupt()) 710 wake_up(&ec->wait); 711 } 712 713 static void start_transaction(struct acpi_ec *ec) 714 { 715 ec->curr->irq_count = ec->curr->wi = ec->curr->ri = 0; 716 ec->curr->flags = 0; 717 } 718 719 static int ec_guard(struct acpi_ec *ec) 720 { 721 unsigned long guard = usecs_to_jiffies(ec->polling_guard); 722 unsigned long timeout = ec->timestamp + guard; 723 724 /* Ensure guarding period before polling EC status */ 725 do { 726 if (ec->busy_polling) { 727 /* Perform busy polling */ 728 if (ec_transaction_completed(ec)) 729 return 0; 730 udelay(jiffies_to_usecs(guard)); 731 } else { 732 /* 733 * Perform wait polling 734 * 1. Wait the transaction to be completed by the 735 * GPE handler after the transaction enters 736 * ACPI_EC_COMMAND_POLL state. 737 * 2. A special guarding logic is also required 738 * for event clearing mode "event" before the 739 * transaction enters ACPI_EC_COMMAND_POLL 740 * state. 741 */ 742 if (!ec_transaction_polled(ec) && 743 !acpi_ec_guard_event(ec)) 744 break; 745 if (wait_event_timeout(ec->wait, 746 ec_transaction_completed(ec), 747 guard)) 748 return 0; 749 } 750 } while (time_before(jiffies, timeout)); 751 return -ETIME; 752 } 753 754 static int ec_poll(struct acpi_ec *ec) 755 { 756 unsigned long flags; 757 int repeat = 5; /* number of command restarts */ 758 759 while (repeat--) { 760 unsigned long delay = jiffies + 761 msecs_to_jiffies(ec_delay); 762 do { 763 if (!ec_guard(ec)) 764 return 0; 765 spin_lock_irqsave(&ec->lock, flags); 766 advance_transaction(ec); 767 spin_unlock_irqrestore(&ec->lock, flags); 768 } while (time_before(jiffies, delay)); 769 pr_debug("controller reset, restart transaction\n"); 770 spin_lock_irqsave(&ec->lock, flags); 771 start_transaction(ec); 772 spin_unlock_irqrestore(&ec->lock, flags); 773 } 774 return -ETIME; 775 } 776 777 static int acpi_ec_transaction_unlocked(struct acpi_ec *ec, 778 struct transaction *t) 779 { 780 unsigned long tmp; 781 int ret = 0; 782 783 /* start transaction */ 784 spin_lock_irqsave(&ec->lock, tmp); 785 /* Enable GPE for command processing (IBF=0/OBF=1) */ 786 if (!acpi_ec_submit_flushable_request(ec)) { 787 ret = -EINVAL; 788 goto unlock; 789 } 790 ec_dbg_ref(ec, "Increase command"); 791 /* following two actions should be kept atomic */ 792 ec->curr = t; 793 ec_dbg_req("Command(%s) started", acpi_ec_cmd_string(t->command)); 794 start_transaction(ec); 795 spin_unlock_irqrestore(&ec->lock, tmp); 796 797 ret = ec_poll(ec); 798 799 spin_lock_irqsave(&ec->lock, tmp); 800 if (t->irq_count == ec_storm_threshold) 801 acpi_ec_clear_storm(ec, EC_FLAGS_COMMAND_STORM); 802 ec_dbg_req("Command(%s) stopped", acpi_ec_cmd_string(t->command)); 803 ec->curr = NULL; 804 /* Disable GPE for command processing (IBF=0/OBF=1) */ 805 acpi_ec_complete_request(ec); 806 ec_dbg_ref(ec, "Decrease command"); 807 unlock: 808 spin_unlock_irqrestore(&ec->lock, tmp); 809 return ret; 810 } 811 812 static int acpi_ec_transaction(struct acpi_ec *ec, struct transaction *t) 813 { 814 int status; 815 u32 glk; 816 817 if (!ec || (!t) || (t->wlen && !t->wdata) || (t->rlen && !t->rdata)) 818 return -EINVAL; 819 if (t->rdata) 820 memset(t->rdata, 0, t->rlen); 821 822 mutex_lock(&ec->mutex); 823 if (ec->global_lock) { 824 status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk); 825 if (ACPI_FAILURE(status)) { 826 status = -ENODEV; 827 goto unlock; 828 } 829 } 830 831 status = acpi_ec_transaction_unlocked(ec, t); 832 833 if (ec->global_lock) 834 acpi_release_global_lock(glk); 835 unlock: 836 mutex_unlock(&ec->mutex); 837 return status; 838 } 839 840 static int acpi_ec_burst_enable(struct acpi_ec *ec) 841 { 842 u8 d; 843 struct transaction t = {.command = ACPI_EC_BURST_ENABLE, 844 .wdata = NULL, .rdata = &d, 845 .wlen = 0, .rlen = 1}; 846 847 return acpi_ec_transaction(ec, &t); 848 } 849 850 static int acpi_ec_burst_disable(struct acpi_ec *ec) 851 { 852 struct transaction t = {.command = ACPI_EC_BURST_DISABLE, 853 .wdata = NULL, .rdata = NULL, 854 .wlen = 0, .rlen = 0}; 855 856 return (acpi_ec_read_status(ec) & ACPI_EC_FLAG_BURST) ? 857 acpi_ec_transaction(ec, &t) : 0; 858 } 859 860 static int acpi_ec_read(struct acpi_ec *ec, u8 address, u8 *data) 861 { 862 int result; 863 u8 d; 864 struct transaction t = {.command = ACPI_EC_COMMAND_READ, 865 .wdata = &address, .rdata = &d, 866 .wlen = 1, .rlen = 1}; 867 868 result = acpi_ec_transaction(ec, &t); 869 *data = d; 870 return result; 871 } 872 873 static int acpi_ec_write(struct acpi_ec *ec, u8 address, u8 data) 874 { 875 u8 wdata[2] = { address, data }; 876 struct transaction t = {.command = ACPI_EC_COMMAND_WRITE, 877 .wdata = wdata, .rdata = NULL, 878 .wlen = 2, .rlen = 0}; 879 880 return acpi_ec_transaction(ec, &t); 881 } 882 883 int ec_read(u8 addr, u8 *val) 884 { 885 int err; 886 u8 temp_data; 887 888 if (!first_ec) 889 return -ENODEV; 890 891 err = acpi_ec_read(first_ec, addr, &temp_data); 892 893 if (!err) { 894 *val = temp_data; 895 return 0; 896 } 897 return err; 898 } 899 EXPORT_SYMBOL(ec_read); 900 901 int ec_write(u8 addr, u8 val) 902 { 903 int err; 904 905 if (!first_ec) 906 return -ENODEV; 907 908 err = acpi_ec_write(first_ec, addr, val); 909 910 return err; 911 } 912 EXPORT_SYMBOL(ec_write); 913 914 int ec_transaction(u8 command, 915 const u8 *wdata, unsigned wdata_len, 916 u8 *rdata, unsigned rdata_len) 917 { 918 struct transaction t = {.command = command, 919 .wdata = wdata, .rdata = rdata, 920 .wlen = wdata_len, .rlen = rdata_len}; 921 922 if (!first_ec) 923 return -ENODEV; 924 925 return acpi_ec_transaction(first_ec, &t); 926 } 927 EXPORT_SYMBOL(ec_transaction); 928 929 /* Get the handle to the EC device */ 930 acpi_handle ec_get_handle(void) 931 { 932 if (!first_ec) 933 return NULL; 934 return first_ec->handle; 935 } 936 EXPORT_SYMBOL(ec_get_handle); 937 938 static void acpi_ec_start(struct acpi_ec *ec, bool resuming) 939 { 940 unsigned long flags; 941 942 spin_lock_irqsave(&ec->lock, flags); 943 if (!test_and_set_bit(EC_FLAGS_STARTED, &ec->flags)) { 944 ec_dbg_drv("Starting EC"); 945 /* Enable GPE for event processing (SCI_EVT=1) */ 946 if (!resuming) { 947 acpi_ec_submit_request(ec); 948 ec_dbg_ref(ec, "Increase driver"); 949 } 950 ec_log_drv("EC started"); 951 } 952 spin_unlock_irqrestore(&ec->lock, flags); 953 } 954 955 static bool acpi_ec_stopped(struct acpi_ec *ec) 956 { 957 unsigned long flags; 958 bool flushed; 959 960 spin_lock_irqsave(&ec->lock, flags); 961 flushed = acpi_ec_flushed(ec); 962 spin_unlock_irqrestore(&ec->lock, flags); 963 return flushed; 964 } 965 966 static void acpi_ec_stop(struct acpi_ec *ec, bool suspending) 967 { 968 unsigned long flags; 969 970 spin_lock_irqsave(&ec->lock, flags); 971 if (acpi_ec_started(ec)) { 972 ec_dbg_drv("Stopping EC"); 973 set_bit(EC_FLAGS_STOPPED, &ec->flags); 974 spin_unlock_irqrestore(&ec->lock, flags); 975 wait_event(ec->wait, acpi_ec_stopped(ec)); 976 spin_lock_irqsave(&ec->lock, flags); 977 /* Disable GPE for event processing (SCI_EVT=1) */ 978 if (!suspending) { 979 acpi_ec_complete_request(ec); 980 ec_dbg_ref(ec, "Decrease driver"); 981 } else if (!ec_freeze_events) 982 __acpi_ec_disable_event(ec); 983 clear_bit(EC_FLAGS_STARTED, &ec->flags); 984 clear_bit(EC_FLAGS_STOPPED, &ec->flags); 985 ec_log_drv("EC stopped"); 986 } 987 spin_unlock_irqrestore(&ec->lock, flags); 988 } 989 990 static void acpi_ec_enter_noirq(struct acpi_ec *ec) 991 { 992 unsigned long flags; 993 994 spin_lock_irqsave(&ec->lock, flags); 995 ec->busy_polling = true; 996 ec->polling_guard = 0; 997 ec_log_drv("interrupt blocked"); 998 spin_unlock_irqrestore(&ec->lock, flags); 999 } 1000 1001 static void acpi_ec_leave_noirq(struct acpi_ec *ec) 1002 { 1003 unsigned long flags; 1004 1005 spin_lock_irqsave(&ec->lock, flags); 1006 ec->busy_polling = ec_busy_polling; 1007 ec->polling_guard = ec_polling_guard; 1008 ec_log_drv("interrupt unblocked"); 1009 spin_unlock_irqrestore(&ec->lock, flags); 1010 } 1011 1012 void acpi_ec_block_transactions(void) 1013 { 1014 struct acpi_ec *ec = first_ec; 1015 1016 if (!ec) 1017 return; 1018 1019 mutex_lock(&ec->mutex); 1020 /* Prevent transactions from being carried out */ 1021 acpi_ec_stop(ec, true); 1022 mutex_unlock(&ec->mutex); 1023 } 1024 1025 void acpi_ec_unblock_transactions(void) 1026 { 1027 /* 1028 * Allow transactions to happen again (this function is called from 1029 * atomic context during wakeup, so we don't need to acquire the mutex). 1030 */ 1031 if (first_ec) 1032 acpi_ec_start(first_ec, true); 1033 } 1034 1035 /* -------------------------------------------------------------------------- 1036 Event Management 1037 -------------------------------------------------------------------------- */ 1038 static struct acpi_ec_query_handler * 1039 acpi_ec_get_query_handler(struct acpi_ec_query_handler *handler) 1040 { 1041 if (handler) 1042 kref_get(&handler->kref); 1043 return handler; 1044 } 1045 1046 static struct acpi_ec_query_handler * 1047 acpi_ec_get_query_handler_by_value(struct acpi_ec *ec, u8 value) 1048 { 1049 struct acpi_ec_query_handler *handler; 1050 bool found = false; 1051 1052 mutex_lock(&ec->mutex); 1053 list_for_each_entry(handler, &ec->list, node) { 1054 if (value == handler->query_bit) { 1055 found = true; 1056 break; 1057 } 1058 } 1059 mutex_unlock(&ec->mutex); 1060 return found ? acpi_ec_get_query_handler(handler) : NULL; 1061 } 1062 1063 static void acpi_ec_query_handler_release(struct kref *kref) 1064 { 1065 struct acpi_ec_query_handler *handler = 1066 container_of(kref, struct acpi_ec_query_handler, kref); 1067 1068 kfree(handler); 1069 } 1070 1071 static void acpi_ec_put_query_handler(struct acpi_ec_query_handler *handler) 1072 { 1073 kref_put(&handler->kref, acpi_ec_query_handler_release); 1074 } 1075 1076 int acpi_ec_add_query_handler(struct acpi_ec *ec, u8 query_bit, 1077 acpi_handle handle, acpi_ec_query_func func, 1078 void *data) 1079 { 1080 struct acpi_ec_query_handler *handler = 1081 kzalloc(sizeof(struct acpi_ec_query_handler), GFP_KERNEL); 1082 1083 if (!handler) 1084 return -ENOMEM; 1085 1086 handler->query_bit = query_bit; 1087 handler->handle = handle; 1088 handler->func = func; 1089 handler->data = data; 1090 mutex_lock(&ec->mutex); 1091 kref_init(&handler->kref); 1092 list_add(&handler->node, &ec->list); 1093 mutex_unlock(&ec->mutex); 1094 return 0; 1095 } 1096 EXPORT_SYMBOL_GPL(acpi_ec_add_query_handler); 1097 1098 static void acpi_ec_remove_query_handlers(struct acpi_ec *ec, 1099 bool remove_all, u8 query_bit) 1100 { 1101 struct acpi_ec_query_handler *handler, *tmp; 1102 LIST_HEAD(free_list); 1103 1104 mutex_lock(&ec->mutex); 1105 list_for_each_entry_safe(handler, tmp, &ec->list, node) { 1106 if (remove_all || query_bit == handler->query_bit) { 1107 list_del_init(&handler->node); 1108 list_add(&handler->node, &free_list); 1109 } 1110 } 1111 mutex_unlock(&ec->mutex); 1112 list_for_each_entry_safe(handler, tmp, &free_list, node) 1113 acpi_ec_put_query_handler(handler); 1114 } 1115 1116 void acpi_ec_remove_query_handler(struct acpi_ec *ec, u8 query_bit) 1117 { 1118 acpi_ec_remove_query_handlers(ec, false, query_bit); 1119 } 1120 EXPORT_SYMBOL_GPL(acpi_ec_remove_query_handler); 1121 1122 static struct acpi_ec_query *acpi_ec_create_query(u8 *pval) 1123 { 1124 struct acpi_ec_query *q; 1125 struct transaction *t; 1126 1127 q = kzalloc(sizeof (struct acpi_ec_query), GFP_KERNEL); 1128 if (!q) 1129 return NULL; 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 return q; 1136 } 1137 1138 static void acpi_ec_delete_query(struct acpi_ec_query *q) 1139 { 1140 if (q) { 1141 if (q->handler) 1142 acpi_ec_put_query_handler(q->handler); 1143 kfree(q); 1144 } 1145 } 1146 1147 static void acpi_ec_event_processor(struct work_struct *work) 1148 { 1149 struct acpi_ec_query *q = container_of(work, struct acpi_ec_query, work); 1150 struct acpi_ec_query_handler *handler = q->handler; 1151 1152 ec_dbg_evt("Query(0x%02x) started", handler->query_bit); 1153 if (handler->func) 1154 handler->func(handler->data); 1155 else if (handler->handle) 1156 acpi_evaluate_object(handler->handle, NULL, NULL, NULL); 1157 ec_dbg_evt("Query(0x%02x) stopped", handler->query_bit); 1158 acpi_ec_delete_query(q); 1159 } 1160 1161 static int acpi_ec_query(struct acpi_ec *ec, u8 *data) 1162 { 1163 u8 value = 0; 1164 int result; 1165 struct acpi_ec_query *q; 1166 1167 q = acpi_ec_create_query(&value); 1168 if (!q) 1169 return -ENOMEM; 1170 1171 /* 1172 * Query the EC to find out which _Qxx method we need to evaluate. 1173 * Note that successful completion of the query causes the ACPI_EC_SCI 1174 * bit to be cleared (and thus clearing the interrupt source). 1175 */ 1176 result = acpi_ec_transaction(ec, &q->transaction); 1177 if (!value) 1178 result = -ENODATA; 1179 if (result) 1180 goto err_exit; 1181 1182 q->handler = acpi_ec_get_query_handler_by_value(ec, value); 1183 if (!q->handler) { 1184 result = -ENODATA; 1185 goto err_exit; 1186 } 1187 1188 /* 1189 * It is reported that _Qxx are evaluated in a parallel way on 1190 * Windows: 1191 * https://bugzilla.kernel.org/show_bug.cgi?id=94411 1192 * 1193 * Put this log entry before schedule_work() in order to make 1194 * it appearing before any other log entries occurred during the 1195 * work queue execution. 1196 */ 1197 ec_dbg_evt("Query(0x%02x) scheduled", value); 1198 if (!queue_work(ec_query_wq, &q->work)) { 1199 ec_dbg_evt("Query(0x%02x) overlapped", value); 1200 result = -EBUSY; 1201 } 1202 1203 err_exit: 1204 if (result) 1205 acpi_ec_delete_query(q); 1206 if (data) 1207 *data = value; 1208 return result; 1209 } 1210 1211 static void acpi_ec_check_event(struct acpi_ec *ec) 1212 { 1213 unsigned long flags; 1214 1215 if (ec_event_clearing == ACPI_EC_EVT_TIMING_EVENT) { 1216 if (ec_guard(ec)) { 1217 spin_lock_irqsave(&ec->lock, flags); 1218 /* 1219 * Take care of the SCI_EVT unless no one else is 1220 * taking care of it. 1221 */ 1222 if (!ec->curr) 1223 advance_transaction(ec); 1224 spin_unlock_irqrestore(&ec->lock, flags); 1225 } 1226 } 1227 } 1228 1229 static void acpi_ec_event_handler(struct work_struct *work) 1230 { 1231 unsigned long flags; 1232 struct acpi_ec *ec = container_of(work, struct acpi_ec, work); 1233 1234 ec_dbg_evt("Event started"); 1235 1236 spin_lock_irqsave(&ec->lock, flags); 1237 while (ec->nr_pending_queries) { 1238 spin_unlock_irqrestore(&ec->lock, flags); 1239 (void)acpi_ec_query(ec, NULL); 1240 spin_lock_irqsave(&ec->lock, flags); 1241 ec->nr_pending_queries--; 1242 /* 1243 * Before exit, make sure that this work item can be 1244 * scheduled again. There might be QR_EC failures, leaving 1245 * EC_FLAGS_QUERY_PENDING uncleared and preventing this work 1246 * item from being scheduled again. 1247 */ 1248 if (!ec->nr_pending_queries) { 1249 if (ec_event_clearing == ACPI_EC_EVT_TIMING_STATUS || 1250 ec_event_clearing == ACPI_EC_EVT_TIMING_QUERY) 1251 acpi_ec_complete_query(ec); 1252 } 1253 } 1254 spin_unlock_irqrestore(&ec->lock, flags); 1255 1256 ec_dbg_evt("Event stopped"); 1257 1258 acpi_ec_check_event(ec); 1259 } 1260 1261 static u32 acpi_ec_gpe_handler(acpi_handle gpe_device, 1262 u32 gpe_number, void *data) 1263 { 1264 unsigned long flags; 1265 struct acpi_ec *ec = data; 1266 1267 spin_lock_irqsave(&ec->lock, flags); 1268 advance_transaction(ec); 1269 spin_unlock_irqrestore(&ec->lock, flags); 1270 return ACPI_INTERRUPT_HANDLED; 1271 } 1272 1273 /* -------------------------------------------------------------------------- 1274 * Address Space Management 1275 * -------------------------------------------------------------------------- */ 1276 1277 static acpi_status 1278 acpi_ec_space_handler(u32 function, acpi_physical_address address, 1279 u32 bits, u64 *value64, 1280 void *handler_context, void *region_context) 1281 { 1282 struct acpi_ec *ec = handler_context; 1283 int result = 0, i, bytes = bits / 8; 1284 u8 *value = (u8 *)value64; 1285 1286 if ((address > 0xFF) || !value || !handler_context) 1287 return AE_BAD_PARAMETER; 1288 1289 if (function != ACPI_READ && function != ACPI_WRITE) 1290 return AE_BAD_PARAMETER; 1291 1292 if (ec->busy_polling || bits > 8) 1293 acpi_ec_burst_enable(ec); 1294 1295 for (i = 0; i < bytes; ++i, ++address, ++value) 1296 result = (function == ACPI_READ) ? 1297 acpi_ec_read(ec, address, value) : 1298 acpi_ec_write(ec, address, *value); 1299 1300 if (ec->busy_polling || bits > 8) 1301 acpi_ec_burst_disable(ec); 1302 1303 switch (result) { 1304 case -EINVAL: 1305 return AE_BAD_PARAMETER; 1306 case -ENODEV: 1307 return AE_NOT_FOUND; 1308 case -ETIME: 1309 return AE_TIME; 1310 default: 1311 return AE_OK; 1312 } 1313 } 1314 1315 /* -------------------------------------------------------------------------- 1316 * Driver Interface 1317 * -------------------------------------------------------------------------- */ 1318 1319 static acpi_status 1320 ec_parse_io_ports(struct acpi_resource *resource, void *context); 1321 1322 static void acpi_ec_free(struct acpi_ec *ec) 1323 { 1324 if (first_ec == ec) 1325 first_ec = NULL; 1326 if (boot_ec == ec) 1327 boot_ec = NULL; 1328 kfree(ec); 1329 } 1330 1331 static struct acpi_ec *acpi_ec_alloc(void) 1332 { 1333 struct acpi_ec *ec = kzalloc(sizeof(struct acpi_ec), GFP_KERNEL); 1334 1335 if (!ec) 1336 return NULL; 1337 mutex_init(&ec->mutex); 1338 init_waitqueue_head(&ec->wait); 1339 INIT_LIST_HEAD(&ec->list); 1340 spin_lock_init(&ec->lock); 1341 INIT_WORK(&ec->work, acpi_ec_event_handler); 1342 ec->timestamp = jiffies; 1343 ec->busy_polling = true; 1344 ec->polling_guard = 0; 1345 return ec; 1346 } 1347 1348 static acpi_status 1349 acpi_ec_register_query_methods(acpi_handle handle, u32 level, 1350 void *context, void **return_value) 1351 { 1352 char node_name[5]; 1353 struct acpi_buffer buffer = { sizeof(node_name), node_name }; 1354 struct acpi_ec *ec = context; 1355 int value = 0; 1356 acpi_status status; 1357 1358 status = acpi_get_name(handle, ACPI_SINGLE_NAME, &buffer); 1359 1360 if (ACPI_SUCCESS(status) && sscanf(node_name, "_Q%x", &value) == 1) 1361 acpi_ec_add_query_handler(ec, value, handle, NULL, NULL); 1362 return AE_OK; 1363 } 1364 1365 static acpi_status 1366 ec_parse_device(acpi_handle handle, u32 Level, void *context, void **retval) 1367 { 1368 acpi_status status; 1369 unsigned long long tmp = 0; 1370 struct acpi_ec *ec = context; 1371 1372 /* clear addr values, ec_parse_io_ports depend on it */ 1373 ec->command_addr = ec->data_addr = 0; 1374 1375 status = acpi_walk_resources(handle, METHOD_NAME__CRS, 1376 ec_parse_io_ports, ec); 1377 if (ACPI_FAILURE(status)) 1378 return status; 1379 if (ec->data_addr == 0 || ec->command_addr == 0) 1380 return AE_OK; 1381 1382 if (boot_ec && boot_ec_is_ecdt && EC_FLAGS_IGNORE_DSDT_GPE) { 1383 /* 1384 * Always inherit the GPE number setting from the ECDT 1385 * EC. 1386 */ 1387 ec->gpe = boot_ec->gpe; 1388 } else { 1389 /* Get GPE bit assignment (EC events). */ 1390 /* TODO: Add support for _GPE returning a package */ 1391 status = acpi_evaluate_integer(handle, "_GPE", NULL, &tmp); 1392 if (ACPI_FAILURE(status)) 1393 return status; 1394 ec->gpe = tmp; 1395 } 1396 /* Use the global lock for all EC transactions? */ 1397 tmp = 0; 1398 acpi_evaluate_integer(handle, "_GLK", NULL, &tmp); 1399 ec->global_lock = tmp; 1400 ec->handle = handle; 1401 return AE_CTRL_TERMINATE; 1402 } 1403 1404 /* 1405 * Note: This function returns an error code only when the address space 1406 * handler is not installed, which means "not able to handle 1407 * transactions". 1408 */ 1409 static int ec_install_handlers(struct acpi_ec *ec, bool handle_events) 1410 { 1411 acpi_status status; 1412 1413 acpi_ec_start(ec, false); 1414 1415 if (!test_bit(EC_FLAGS_EC_HANDLER_INSTALLED, &ec->flags)) { 1416 acpi_ec_enter_noirq(ec); 1417 status = acpi_install_address_space_handler(ec->handle, 1418 ACPI_ADR_SPACE_EC, 1419 &acpi_ec_space_handler, 1420 NULL, ec); 1421 if (ACPI_FAILURE(status)) { 1422 if (status == AE_NOT_FOUND) { 1423 /* 1424 * Maybe OS fails in evaluating the _REG 1425 * object. The AE_NOT_FOUND error will be 1426 * ignored and OS * continue to initialize 1427 * EC. 1428 */ 1429 pr_err("Fail in evaluating the _REG object" 1430 " of EC device. Broken bios is suspected.\n"); 1431 } else { 1432 acpi_ec_stop(ec, false); 1433 return -ENODEV; 1434 } 1435 } 1436 set_bit(EC_FLAGS_EC_HANDLER_INSTALLED, &ec->flags); 1437 } 1438 1439 if (!handle_events) 1440 return 0; 1441 1442 if (!test_bit(EC_FLAGS_EVT_HANDLER_INSTALLED, &ec->flags)) { 1443 /* Find and register all query methods */ 1444 acpi_walk_namespace(ACPI_TYPE_METHOD, ec->handle, 1, 1445 acpi_ec_register_query_methods, 1446 NULL, ec, NULL); 1447 set_bit(EC_FLAGS_EVT_HANDLER_INSTALLED, &ec->flags); 1448 } 1449 if (!test_bit(EC_FLAGS_GPE_HANDLER_INSTALLED, &ec->flags)) { 1450 status = acpi_install_gpe_raw_handler(NULL, ec->gpe, 1451 ACPI_GPE_EDGE_TRIGGERED, 1452 &acpi_ec_gpe_handler, ec); 1453 /* This is not fatal as we can poll EC events */ 1454 if (ACPI_SUCCESS(status)) { 1455 set_bit(EC_FLAGS_GPE_HANDLER_INSTALLED, &ec->flags); 1456 acpi_ec_leave_noirq(ec); 1457 if (test_bit(EC_FLAGS_STARTED, &ec->flags) && 1458 ec->reference_count >= 1) 1459 acpi_ec_enable_gpe(ec, true); 1460 1461 /* EC is fully operational, allow queries */ 1462 acpi_ec_enable_event(ec); 1463 } 1464 } 1465 1466 return 0; 1467 } 1468 1469 static void ec_remove_handlers(struct acpi_ec *ec) 1470 { 1471 if (test_bit(EC_FLAGS_EC_HANDLER_INSTALLED, &ec->flags)) { 1472 if (ACPI_FAILURE(acpi_remove_address_space_handler(ec->handle, 1473 ACPI_ADR_SPACE_EC, &acpi_ec_space_handler))) 1474 pr_err("failed to remove space handler\n"); 1475 clear_bit(EC_FLAGS_EC_HANDLER_INSTALLED, &ec->flags); 1476 } 1477 1478 /* 1479 * Stops handling the EC transactions after removing the operation 1480 * region handler. This is required because _REG(DISCONNECT) 1481 * invoked during the removal can result in new EC transactions. 1482 * 1483 * Flushes the EC requests and thus disables the GPE before 1484 * removing the GPE handler. This is required by the current ACPICA 1485 * GPE core. ACPICA GPE core will automatically disable a GPE when 1486 * it is indicated but there is no way to handle it. So the drivers 1487 * must disable the GPEs prior to removing the GPE handlers. 1488 */ 1489 acpi_ec_stop(ec, false); 1490 1491 if (test_bit(EC_FLAGS_GPE_HANDLER_INSTALLED, &ec->flags)) { 1492 if (ACPI_FAILURE(acpi_remove_gpe_handler(NULL, ec->gpe, 1493 &acpi_ec_gpe_handler))) 1494 pr_err("failed to remove gpe handler\n"); 1495 clear_bit(EC_FLAGS_GPE_HANDLER_INSTALLED, &ec->flags); 1496 } 1497 if (test_bit(EC_FLAGS_EVT_HANDLER_INSTALLED, &ec->flags)) { 1498 acpi_ec_remove_query_handlers(ec, true, 0); 1499 clear_bit(EC_FLAGS_EVT_HANDLER_INSTALLED, &ec->flags); 1500 } 1501 } 1502 1503 static int acpi_ec_setup(struct acpi_ec *ec, bool handle_events) 1504 { 1505 int ret; 1506 1507 ret = ec_install_handlers(ec, handle_events); 1508 if (ret) 1509 return ret; 1510 1511 /* First EC capable of handling transactions */ 1512 if (!first_ec) { 1513 first_ec = ec; 1514 acpi_handle_info(first_ec->handle, "Used as first EC\n"); 1515 } 1516 1517 acpi_handle_info(ec->handle, 1518 "GPE=0x%lx, EC_CMD/EC_SC=0x%lx, EC_DATA=0x%lx\n", 1519 ec->gpe, ec->command_addr, ec->data_addr); 1520 return ret; 1521 } 1522 1523 static int acpi_config_boot_ec(struct acpi_ec *ec, acpi_handle handle, 1524 bool handle_events, bool is_ecdt) 1525 { 1526 int ret; 1527 1528 /* 1529 * Changing the ACPI handle results in a re-configuration of the 1530 * boot EC. And if it happens after the namespace initialization, 1531 * it causes _REG evaluations. 1532 */ 1533 if (boot_ec && boot_ec->handle != handle) 1534 ec_remove_handlers(boot_ec); 1535 1536 /* Unset old boot EC */ 1537 if (boot_ec != ec) 1538 acpi_ec_free(boot_ec); 1539 1540 /* 1541 * ECDT device creation is split into acpi_ec_ecdt_probe() and 1542 * acpi_ec_ecdt_start(). This function takes care of completing the 1543 * ECDT parsing logic as the handle update should be performed 1544 * between the installation/uninstallation of the handlers. 1545 */ 1546 if (ec->handle != handle) 1547 ec->handle = handle; 1548 1549 ret = acpi_ec_setup(ec, handle_events); 1550 if (ret) 1551 return ret; 1552 1553 /* Set new boot EC */ 1554 if (!boot_ec) { 1555 boot_ec = ec; 1556 boot_ec_is_ecdt = is_ecdt; 1557 } 1558 1559 acpi_handle_info(boot_ec->handle, 1560 "Used as boot %s EC to handle transactions%s\n", 1561 is_ecdt ? "ECDT" : "DSDT", 1562 handle_events ? " and events" : ""); 1563 return ret; 1564 } 1565 1566 static bool acpi_ec_ecdt_get_handle(acpi_handle *phandle) 1567 { 1568 struct acpi_table_ecdt *ecdt_ptr; 1569 acpi_status status; 1570 acpi_handle handle; 1571 1572 status = acpi_get_table(ACPI_SIG_ECDT, 1, 1573 (struct acpi_table_header **)&ecdt_ptr); 1574 if (ACPI_FAILURE(status)) 1575 return false; 1576 1577 status = acpi_get_handle(NULL, ecdt_ptr->id, &handle); 1578 if (ACPI_FAILURE(status)) 1579 return false; 1580 1581 *phandle = handle; 1582 return true; 1583 } 1584 1585 static bool acpi_is_boot_ec(struct acpi_ec *ec) 1586 { 1587 if (!boot_ec) 1588 return false; 1589 if (ec->handle == boot_ec->handle && 1590 ec->gpe == boot_ec->gpe && 1591 ec->command_addr == boot_ec->command_addr && 1592 ec->data_addr == boot_ec->data_addr) 1593 return true; 1594 return false; 1595 } 1596 1597 static int acpi_ec_add(struct acpi_device *device) 1598 { 1599 struct acpi_ec *ec = NULL; 1600 int ret; 1601 1602 strcpy(acpi_device_name(device), ACPI_EC_DEVICE_NAME); 1603 strcpy(acpi_device_class(device), ACPI_EC_CLASS); 1604 1605 ec = acpi_ec_alloc(); 1606 if (!ec) 1607 return -ENOMEM; 1608 if (ec_parse_device(device->handle, 0, ec, NULL) != 1609 AE_CTRL_TERMINATE) { 1610 ret = -EINVAL; 1611 goto err_alloc; 1612 } 1613 1614 if (acpi_is_boot_ec(ec)) { 1615 boot_ec_is_ecdt = false; 1616 acpi_handle_debug(ec->handle, "duplicated.\n"); 1617 acpi_ec_free(ec); 1618 ec = boot_ec; 1619 ret = acpi_config_boot_ec(ec, ec->handle, true, false); 1620 } else 1621 ret = acpi_ec_setup(ec, true); 1622 if (ret) 1623 goto err_query; 1624 1625 device->driver_data = ec; 1626 1627 ret = !!request_region(ec->data_addr, 1, "EC data"); 1628 WARN(!ret, "Could not request EC data io port 0x%lx", ec->data_addr); 1629 ret = !!request_region(ec->command_addr, 1, "EC cmd"); 1630 WARN(!ret, "Could not request EC cmd io port 0x%lx", ec->command_addr); 1631 1632 /* Reprobe devices depending on the EC */ 1633 acpi_walk_dep_device_list(ec->handle); 1634 acpi_handle_debug(ec->handle, "enumerated.\n"); 1635 return 0; 1636 1637 err_query: 1638 if (ec != boot_ec) 1639 acpi_ec_remove_query_handlers(ec, true, 0); 1640 err_alloc: 1641 if (ec != boot_ec) 1642 acpi_ec_free(ec); 1643 return ret; 1644 } 1645 1646 static int acpi_ec_remove(struct acpi_device *device) 1647 { 1648 struct acpi_ec *ec; 1649 1650 if (!device) 1651 return -EINVAL; 1652 1653 ec = acpi_driver_data(device); 1654 release_region(ec->data_addr, 1); 1655 release_region(ec->command_addr, 1); 1656 device->driver_data = NULL; 1657 if (ec != boot_ec) { 1658 ec_remove_handlers(ec); 1659 acpi_ec_free(ec); 1660 } 1661 return 0; 1662 } 1663 1664 static acpi_status 1665 ec_parse_io_ports(struct acpi_resource *resource, void *context) 1666 { 1667 struct acpi_ec *ec = context; 1668 1669 if (resource->type != ACPI_RESOURCE_TYPE_IO) 1670 return AE_OK; 1671 1672 /* 1673 * The first address region returned is the data port, and 1674 * the second address region returned is the status/command 1675 * port. 1676 */ 1677 if (ec->data_addr == 0) 1678 ec->data_addr = resource->data.io.minimum; 1679 else if (ec->command_addr == 0) 1680 ec->command_addr = resource->data.io.minimum; 1681 else 1682 return AE_CTRL_TERMINATE; 1683 1684 return AE_OK; 1685 } 1686 1687 static const struct acpi_device_id ec_device_ids[] = { 1688 {"PNP0C09", 0}, 1689 {"", 0}, 1690 }; 1691 1692 /* 1693 * This function is not Windows-compatible as Windows never enumerates the 1694 * namespace EC before the main ACPI device enumeration process. It is 1695 * retained for historical reason and will be deprecated in the future. 1696 */ 1697 int __init acpi_ec_dsdt_probe(void) 1698 { 1699 acpi_status status; 1700 struct acpi_ec *ec; 1701 int ret; 1702 1703 /* 1704 * If a platform has ECDT, there is no need to proceed as the 1705 * following probe is not a part of the ACPI device enumeration, 1706 * executing _STA is not safe, and thus this probe may risk of 1707 * picking up an invalid EC device. 1708 */ 1709 if (boot_ec) 1710 return -ENODEV; 1711 1712 ec = acpi_ec_alloc(); 1713 if (!ec) 1714 return -ENOMEM; 1715 /* 1716 * At this point, the namespace is initialized, so start to find 1717 * the namespace objects. 1718 */ 1719 status = acpi_get_devices(ec_device_ids[0].id, 1720 ec_parse_device, ec, NULL); 1721 if (ACPI_FAILURE(status) || !ec->handle) { 1722 ret = -ENODEV; 1723 goto error; 1724 } 1725 /* 1726 * When the DSDT EC is available, always re-configure boot EC to 1727 * have _REG evaluated. _REG can only be evaluated after the 1728 * namespace initialization. 1729 * At this point, the GPE is not fully initialized, so do not to 1730 * handle the events. 1731 */ 1732 ret = acpi_config_boot_ec(ec, ec->handle, false, false); 1733 error: 1734 if (ret) 1735 acpi_ec_free(ec); 1736 return ret; 1737 } 1738 1739 /* 1740 * If the DSDT EC is not functioning, we still need to prepare a fully 1741 * functioning ECDT EC first in order to handle the events. 1742 * https://bugzilla.kernel.org/show_bug.cgi?id=115021 1743 */ 1744 int __init acpi_ec_ecdt_start(void) 1745 { 1746 acpi_handle handle; 1747 1748 if (!boot_ec) 1749 return -ENODEV; 1750 /* 1751 * The DSDT EC should have already been started in 1752 * acpi_ec_add(). 1753 */ 1754 if (!boot_ec_is_ecdt) 1755 return -ENODEV; 1756 1757 /* 1758 * At this point, the namespace and the GPE is initialized, so 1759 * start to find the namespace objects and handle the events. 1760 */ 1761 if (!acpi_ec_ecdt_get_handle(&handle)) 1762 return -ENODEV; 1763 return acpi_config_boot_ec(boot_ec, handle, true, true); 1764 } 1765 1766 #if 0 1767 /* 1768 * Some EC firmware variations refuses to respond QR_EC when SCI_EVT is not 1769 * set, for which case, we complete the QR_EC without issuing it to the 1770 * firmware. 1771 * https://bugzilla.kernel.org/show_bug.cgi?id=82611 1772 * https://bugzilla.kernel.org/show_bug.cgi?id=97381 1773 */ 1774 static int ec_flag_query_handshake(const struct dmi_system_id *id) 1775 { 1776 pr_debug("Detected the EC firmware requiring QR_EC issued when SCI_EVT set\n"); 1777 EC_FLAGS_QUERY_HANDSHAKE = 1; 1778 return 0; 1779 } 1780 #endif 1781 1782 /* 1783 * Some ECDTs contain wrong register addresses. 1784 * MSI MS-171F 1785 * https://bugzilla.kernel.org/show_bug.cgi?id=12461 1786 */ 1787 static int ec_correct_ecdt(const struct dmi_system_id *id) 1788 { 1789 pr_debug("Detected system needing ECDT address correction.\n"); 1790 EC_FLAGS_CORRECT_ECDT = 1; 1791 return 0; 1792 } 1793 1794 /* 1795 * Some DSDTs contain wrong GPE setting. 1796 * Asus FX502VD/VE, GL702VMK, X550VXK, X580VD 1797 * https://bugzilla.kernel.org/show_bug.cgi?id=195651 1798 */ 1799 static int ec_honor_ecdt_gpe(const struct dmi_system_id *id) 1800 { 1801 pr_debug("Detected system needing ignore DSDT GPE setting.\n"); 1802 EC_FLAGS_IGNORE_DSDT_GPE = 1; 1803 return 0; 1804 } 1805 1806 static struct dmi_system_id ec_dmi_table[] __initdata = { 1807 { 1808 ec_correct_ecdt, "MSI MS-171F", { 1809 DMI_MATCH(DMI_SYS_VENDOR, "Micro-Star"), 1810 DMI_MATCH(DMI_PRODUCT_NAME, "MS-171F"),}, NULL}, 1811 { 1812 ec_honor_ecdt_gpe, "ASUS FX502VD", { 1813 DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK COMPUTER INC."), 1814 DMI_MATCH(DMI_PRODUCT_NAME, "FX502VD"),}, NULL}, 1815 { 1816 ec_honor_ecdt_gpe, "ASUS FX502VE", { 1817 DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK COMPUTER INC."), 1818 DMI_MATCH(DMI_PRODUCT_NAME, "FX502VE"),}, NULL}, 1819 { 1820 ec_honor_ecdt_gpe, "ASUS GL702VMK", { 1821 DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK COMPUTER INC."), 1822 DMI_MATCH(DMI_PRODUCT_NAME, "GL702VMK"),}, NULL}, 1823 { 1824 ec_honor_ecdt_gpe, "ASUS X550VXK", { 1825 DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK COMPUTER INC."), 1826 DMI_MATCH(DMI_PRODUCT_NAME, "X550VXK"),}, NULL}, 1827 { 1828 ec_honor_ecdt_gpe, "ASUS X580VD", { 1829 DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK COMPUTER INC."), 1830 DMI_MATCH(DMI_PRODUCT_NAME, "X580VD"),}, NULL}, 1831 {}, 1832 }; 1833 1834 int __init acpi_ec_ecdt_probe(void) 1835 { 1836 int ret; 1837 acpi_status status; 1838 struct acpi_table_ecdt *ecdt_ptr; 1839 struct acpi_ec *ec; 1840 1841 ec = acpi_ec_alloc(); 1842 if (!ec) 1843 return -ENOMEM; 1844 /* 1845 * Generate a boot ec context 1846 */ 1847 dmi_check_system(ec_dmi_table); 1848 status = acpi_get_table(ACPI_SIG_ECDT, 1, 1849 (struct acpi_table_header **)&ecdt_ptr); 1850 if (ACPI_FAILURE(status)) { 1851 ret = -ENODEV; 1852 goto error; 1853 } 1854 1855 if (!ecdt_ptr->control.address || !ecdt_ptr->data.address) { 1856 /* 1857 * Asus X50GL: 1858 * https://bugzilla.kernel.org/show_bug.cgi?id=11880 1859 */ 1860 ret = -ENODEV; 1861 goto error; 1862 } 1863 1864 if (EC_FLAGS_CORRECT_ECDT) { 1865 ec->command_addr = ecdt_ptr->data.address; 1866 ec->data_addr = ecdt_ptr->control.address; 1867 } else { 1868 ec->command_addr = ecdt_ptr->control.address; 1869 ec->data_addr = ecdt_ptr->data.address; 1870 } 1871 ec->gpe = ecdt_ptr->gpe; 1872 1873 /* 1874 * At this point, the namespace is not initialized, so do not find 1875 * the namespace objects, or handle the events. 1876 */ 1877 ret = acpi_config_boot_ec(ec, ACPI_ROOT_OBJECT, false, true); 1878 error: 1879 if (ret) 1880 acpi_ec_free(ec); 1881 return ret; 1882 } 1883 1884 #ifdef CONFIG_PM_SLEEP 1885 static int acpi_ec_suspend(struct device *dev) 1886 { 1887 struct acpi_ec *ec = 1888 acpi_driver_data(to_acpi_device(dev)); 1889 1890 if (acpi_sleep_no_ec_events() && ec_freeze_events) 1891 acpi_ec_disable_event(ec); 1892 return 0; 1893 } 1894 1895 static int acpi_ec_suspend_noirq(struct device *dev) 1896 { 1897 struct acpi_ec *ec = acpi_driver_data(to_acpi_device(dev)); 1898 1899 /* 1900 * The SCI handler doesn't run at this point, so the GPE can be 1901 * masked at the low level without side effects. 1902 */ 1903 if (ec_no_wakeup && test_bit(EC_FLAGS_STARTED, &ec->flags) && 1904 ec->reference_count >= 1) 1905 acpi_set_gpe(NULL, ec->gpe, ACPI_GPE_DISABLE); 1906 1907 return 0; 1908 } 1909 1910 static int acpi_ec_resume_noirq(struct device *dev) 1911 { 1912 struct acpi_ec *ec = acpi_driver_data(to_acpi_device(dev)); 1913 1914 if (ec_no_wakeup && test_bit(EC_FLAGS_STARTED, &ec->flags) && 1915 ec->reference_count >= 1) 1916 acpi_set_gpe(NULL, ec->gpe, ACPI_GPE_ENABLE); 1917 1918 return 0; 1919 } 1920 1921 static int acpi_ec_resume(struct device *dev) 1922 { 1923 struct acpi_ec *ec = 1924 acpi_driver_data(to_acpi_device(dev)); 1925 1926 acpi_ec_enable_event(ec); 1927 return 0; 1928 } 1929 #endif 1930 1931 static const struct dev_pm_ops acpi_ec_pm = { 1932 SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(acpi_ec_suspend_noirq, acpi_ec_resume_noirq) 1933 SET_SYSTEM_SLEEP_PM_OPS(acpi_ec_suspend, acpi_ec_resume) 1934 }; 1935 1936 static int param_set_event_clearing(const char *val, struct kernel_param *kp) 1937 { 1938 int result = 0; 1939 1940 if (!strncmp(val, "status", sizeof("status") - 1)) { 1941 ec_event_clearing = ACPI_EC_EVT_TIMING_STATUS; 1942 pr_info("Assuming SCI_EVT clearing on EC_SC accesses\n"); 1943 } else if (!strncmp(val, "query", sizeof("query") - 1)) { 1944 ec_event_clearing = ACPI_EC_EVT_TIMING_QUERY; 1945 pr_info("Assuming SCI_EVT clearing on QR_EC writes\n"); 1946 } else if (!strncmp(val, "event", sizeof("event") - 1)) { 1947 ec_event_clearing = ACPI_EC_EVT_TIMING_EVENT; 1948 pr_info("Assuming SCI_EVT clearing on event reads\n"); 1949 } else 1950 result = -EINVAL; 1951 return result; 1952 } 1953 1954 static int param_get_event_clearing(char *buffer, struct kernel_param *kp) 1955 { 1956 switch (ec_event_clearing) { 1957 case ACPI_EC_EVT_TIMING_STATUS: 1958 return sprintf(buffer, "status"); 1959 case ACPI_EC_EVT_TIMING_QUERY: 1960 return sprintf(buffer, "query"); 1961 case ACPI_EC_EVT_TIMING_EVENT: 1962 return sprintf(buffer, "event"); 1963 default: 1964 return sprintf(buffer, "invalid"); 1965 } 1966 return 0; 1967 } 1968 1969 module_param_call(ec_event_clearing, param_set_event_clearing, param_get_event_clearing, 1970 NULL, 0644); 1971 MODULE_PARM_DESC(ec_event_clearing, "Assumed SCI_EVT clearing timing"); 1972 1973 static struct acpi_driver acpi_ec_driver = { 1974 .name = "ec", 1975 .class = ACPI_EC_CLASS, 1976 .ids = ec_device_ids, 1977 .ops = { 1978 .add = acpi_ec_add, 1979 .remove = acpi_ec_remove, 1980 }, 1981 .drv.pm = &acpi_ec_pm, 1982 }; 1983 1984 static inline int acpi_ec_query_init(void) 1985 { 1986 if (!ec_query_wq) { 1987 ec_query_wq = alloc_workqueue("kec_query", 0, 1988 ec_max_queries); 1989 if (!ec_query_wq) 1990 return -ENODEV; 1991 } 1992 return 0; 1993 } 1994 1995 static inline void acpi_ec_query_exit(void) 1996 { 1997 if (ec_query_wq) { 1998 destroy_workqueue(ec_query_wq); 1999 ec_query_wq = NULL; 2000 } 2001 } 2002 2003 int __init acpi_ec_init(void) 2004 { 2005 int result; 2006 2007 /* register workqueue for _Qxx evaluations */ 2008 result = acpi_ec_query_init(); 2009 if (result) 2010 goto err_exit; 2011 /* Now register the driver for the EC */ 2012 result = acpi_bus_register_driver(&acpi_ec_driver); 2013 if (result) 2014 goto err_exit; 2015 2016 err_exit: 2017 if (result) 2018 acpi_ec_query_exit(); 2019 return result; 2020 } 2021 2022 /* EC driver currently not unloadable */ 2023 #if 0 2024 static void __exit acpi_ec_exit(void) 2025 { 2026 2027 acpi_bus_unregister_driver(&acpi_ec_driver); 2028 acpi_ec_query_exit(); 2029 } 2030 #endif /* 0 */ 2031