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 struct acpi_ec_query_handler { 155 struct list_head node; 156 acpi_ec_query_func func; 157 acpi_handle handle; 158 void *data; 159 u8 query_bit; 160 struct kref kref; 161 }; 162 163 struct transaction { 164 const u8 *wdata; 165 u8 *rdata; 166 unsigned short irq_count; 167 u8 command; 168 u8 wi; 169 u8 ri; 170 u8 wlen; 171 u8 rlen; 172 u8 flags; 173 }; 174 175 struct acpi_ec_query { 176 struct transaction transaction; 177 struct work_struct work; 178 struct acpi_ec_query_handler *handler; 179 }; 180 181 static int acpi_ec_query(struct acpi_ec *ec, u8 *data); 182 static void advance_transaction(struct acpi_ec *ec); 183 static void acpi_ec_event_handler(struct work_struct *work); 184 static void acpi_ec_event_processor(struct work_struct *work); 185 186 struct acpi_ec *boot_ec, *first_ec; 187 EXPORT_SYMBOL(first_ec); 188 static bool boot_ec_is_ecdt = false; 189 static struct workqueue_struct *ec_query_wq; 190 191 static int EC_FLAGS_QUERY_HANDSHAKE; /* Needs QR_EC issued when SCI_EVT set */ 192 static int EC_FLAGS_CORRECT_ECDT; /* Needs ECDT port address correction */ 193 static int EC_FLAGS_IGNORE_DSDT_GPE; /* Needs ECDT GPE as correction setting */ 194 195 /* -------------------------------------------------------------------------- 196 * Logging/Debugging 197 * -------------------------------------------------------------------------- */ 198 199 /* 200 * Splitters used by the developers to track the boundary of the EC 201 * handling processes. 202 */ 203 #ifdef DEBUG 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 #else 210 #define EC_DBG_SEP "" 211 #define EC_DBG_DRV 212 #define EC_DBG_STM 213 #define EC_DBG_REQ 214 #define EC_DBG_EVT 215 #endif 216 217 #define ec_log_raw(fmt, ...) \ 218 pr_info(fmt "\n", ##__VA_ARGS__) 219 #define ec_dbg_raw(fmt, ...) \ 220 pr_debug(fmt "\n", ##__VA_ARGS__) 221 #define ec_log(filter, fmt, ...) \ 222 ec_log_raw(filter EC_DBG_SEP fmt EC_DBG_SEP filter, ##__VA_ARGS__) 223 #define ec_dbg(filter, fmt, ...) \ 224 ec_dbg_raw(filter EC_DBG_SEP fmt EC_DBG_SEP filter, ##__VA_ARGS__) 225 226 #define ec_log_drv(fmt, ...) \ 227 ec_log(EC_DBG_DRV, fmt, ##__VA_ARGS__) 228 #define ec_dbg_drv(fmt, ...) \ 229 ec_dbg(EC_DBG_DRV, fmt, ##__VA_ARGS__) 230 #define ec_dbg_stm(fmt, ...) \ 231 ec_dbg(EC_DBG_STM, fmt, ##__VA_ARGS__) 232 #define ec_dbg_req(fmt, ...) \ 233 ec_dbg(EC_DBG_REQ, fmt, ##__VA_ARGS__) 234 #define ec_dbg_evt(fmt, ...) \ 235 ec_dbg(EC_DBG_EVT, fmt, ##__VA_ARGS__) 236 #define ec_dbg_ref(ec, fmt, ...) \ 237 ec_dbg_raw("%lu: " fmt, ec->reference_count, ## __VA_ARGS__) 238 239 /* -------------------------------------------------------------------------- 240 * Device Flags 241 * -------------------------------------------------------------------------- */ 242 243 static bool acpi_ec_started(struct acpi_ec *ec) 244 { 245 return test_bit(EC_FLAGS_STARTED, &ec->flags) && 246 !test_bit(EC_FLAGS_STOPPED, &ec->flags); 247 } 248 249 static bool acpi_ec_event_enabled(struct acpi_ec *ec) 250 { 251 /* 252 * There is an OSPM early stage logic. During the early stages 253 * (boot/resume), OSPMs shouldn't enable the event handling, only 254 * the EC transactions are allowed to be performed. 255 */ 256 if (!test_bit(EC_FLAGS_QUERY_ENABLED, &ec->flags)) 257 return false; 258 /* 259 * However, disabling the event handling is experimental for late 260 * stage (suspend), and is controlled by the boot parameter of 261 * "ec_freeze_events": 262 * 1. true: The EC event handling is disabled before entering 263 * the noirq stage. 264 * 2. false: The EC event handling is automatically disabled as 265 * soon as the EC driver is stopped. 266 */ 267 if (ec_freeze_events) 268 return acpi_ec_started(ec); 269 else 270 return test_bit(EC_FLAGS_STARTED, &ec->flags); 271 } 272 273 static bool acpi_ec_flushed(struct acpi_ec *ec) 274 { 275 return ec->reference_count == 1; 276 } 277 278 /* -------------------------------------------------------------------------- 279 * EC Registers 280 * -------------------------------------------------------------------------- */ 281 282 static inline u8 acpi_ec_read_status(struct acpi_ec *ec) 283 { 284 u8 x = inb(ec->command_addr); 285 286 ec_dbg_raw("EC_SC(R) = 0x%2.2x " 287 "SCI_EVT=%d BURST=%d CMD=%d IBF=%d OBF=%d", 288 x, 289 !!(x & ACPI_EC_FLAG_SCI), 290 !!(x & ACPI_EC_FLAG_BURST), 291 !!(x & ACPI_EC_FLAG_CMD), 292 !!(x & ACPI_EC_FLAG_IBF), 293 !!(x & ACPI_EC_FLAG_OBF)); 294 return x; 295 } 296 297 static inline u8 acpi_ec_read_data(struct acpi_ec *ec) 298 { 299 u8 x = inb(ec->data_addr); 300 301 ec->timestamp = jiffies; 302 ec_dbg_raw("EC_DATA(R) = 0x%2.2x", x); 303 return x; 304 } 305 306 static inline void acpi_ec_write_cmd(struct acpi_ec *ec, u8 command) 307 { 308 ec_dbg_raw("EC_SC(W) = 0x%2.2x", command); 309 outb(command, ec->command_addr); 310 ec->timestamp = jiffies; 311 } 312 313 static inline void acpi_ec_write_data(struct acpi_ec *ec, u8 data) 314 { 315 ec_dbg_raw("EC_DATA(W) = 0x%2.2x", data); 316 outb(data, ec->data_addr); 317 ec->timestamp = jiffies; 318 } 319 320 #if defined(DEBUG) || defined(CONFIG_DYNAMIC_DEBUG) 321 static const char *acpi_ec_cmd_string(u8 cmd) 322 { 323 switch (cmd) { 324 case 0x80: 325 return "RD_EC"; 326 case 0x81: 327 return "WR_EC"; 328 case 0x82: 329 return "BE_EC"; 330 case 0x83: 331 return "BD_EC"; 332 case 0x84: 333 return "QR_EC"; 334 } 335 return "UNKNOWN"; 336 } 337 #else 338 #define acpi_ec_cmd_string(cmd) "UNDEF" 339 #endif 340 341 /* -------------------------------------------------------------------------- 342 * GPE Registers 343 * -------------------------------------------------------------------------- */ 344 345 static inline bool acpi_ec_is_gpe_raised(struct acpi_ec *ec) 346 { 347 acpi_event_status gpe_status = 0; 348 349 (void)acpi_get_gpe_status(NULL, ec->gpe, &gpe_status); 350 return (gpe_status & ACPI_EVENT_FLAG_STATUS_SET) ? true : false; 351 } 352 353 static inline void acpi_ec_enable_gpe(struct acpi_ec *ec, bool open) 354 { 355 if (open) 356 acpi_enable_gpe(NULL, ec->gpe); 357 else { 358 BUG_ON(ec->reference_count < 1); 359 acpi_set_gpe(NULL, ec->gpe, ACPI_GPE_ENABLE); 360 } 361 if (acpi_ec_is_gpe_raised(ec)) { 362 /* 363 * On some platforms, EN=1 writes cannot trigger GPE. So 364 * software need to manually trigger a pseudo GPE event on 365 * EN=1 writes. 366 */ 367 ec_dbg_raw("Polling quirk"); 368 advance_transaction(ec); 369 } 370 } 371 372 static inline void acpi_ec_disable_gpe(struct acpi_ec *ec, bool close) 373 { 374 if (close) 375 acpi_disable_gpe(NULL, ec->gpe); 376 else { 377 BUG_ON(ec->reference_count < 1); 378 acpi_set_gpe(NULL, ec->gpe, ACPI_GPE_DISABLE); 379 } 380 } 381 382 static inline void acpi_ec_clear_gpe(struct acpi_ec *ec) 383 { 384 /* 385 * GPE STS is a W1C register, which means: 386 * 1. Software can clear it without worrying about clearing other 387 * GPEs' STS bits when the hardware sets them in parallel. 388 * 2. As long as software can ensure only clearing it when it is 389 * set, hardware won't set it in parallel. 390 * So software can clear GPE in any contexts. 391 * Warning: do not move the check into advance_transaction() as the 392 * EC commands will be sent without GPE raised. 393 */ 394 if (!acpi_ec_is_gpe_raised(ec)) 395 return; 396 acpi_clear_gpe(NULL, ec->gpe); 397 } 398 399 /* -------------------------------------------------------------------------- 400 * Transaction Management 401 * -------------------------------------------------------------------------- */ 402 403 static void acpi_ec_submit_request(struct acpi_ec *ec) 404 { 405 ec->reference_count++; 406 if (test_bit(EC_FLAGS_GPE_HANDLER_INSTALLED, &ec->flags) && 407 ec->reference_count == 1) 408 acpi_ec_enable_gpe(ec, true); 409 } 410 411 static void acpi_ec_complete_request(struct acpi_ec *ec) 412 { 413 bool flushed = false; 414 415 ec->reference_count--; 416 if (test_bit(EC_FLAGS_GPE_HANDLER_INSTALLED, &ec->flags) && 417 ec->reference_count == 0) 418 acpi_ec_disable_gpe(ec, true); 419 flushed = acpi_ec_flushed(ec); 420 if (flushed) 421 wake_up(&ec->wait); 422 } 423 424 static void acpi_ec_set_storm(struct acpi_ec *ec, u8 flag) 425 { 426 if (!test_bit(flag, &ec->flags)) { 427 acpi_ec_disable_gpe(ec, false); 428 ec_dbg_drv("Polling enabled"); 429 set_bit(flag, &ec->flags); 430 } 431 } 432 433 static void acpi_ec_clear_storm(struct acpi_ec *ec, u8 flag) 434 { 435 if (test_bit(flag, &ec->flags)) { 436 clear_bit(flag, &ec->flags); 437 acpi_ec_enable_gpe(ec, false); 438 ec_dbg_drv("Polling disabled"); 439 } 440 } 441 442 /* 443 * acpi_ec_submit_flushable_request() - Increase the reference count unless 444 * the flush operation is not in 445 * progress 446 * @ec: the EC device 447 * 448 * This function must be used before taking a new action that should hold 449 * the reference count. If this function returns false, then the action 450 * must be discarded or it will prevent the flush operation from being 451 * completed. 452 */ 453 static bool acpi_ec_submit_flushable_request(struct acpi_ec *ec) 454 { 455 if (!acpi_ec_started(ec)) 456 return false; 457 acpi_ec_submit_request(ec); 458 return true; 459 } 460 461 static void acpi_ec_submit_query(struct acpi_ec *ec) 462 { 463 acpi_ec_set_storm(ec, EC_FLAGS_COMMAND_STORM); 464 if (!acpi_ec_event_enabled(ec)) 465 return; 466 if (!test_and_set_bit(EC_FLAGS_QUERY_PENDING, &ec->flags)) { 467 ec_dbg_evt("Command(%s) submitted/blocked", 468 acpi_ec_cmd_string(ACPI_EC_COMMAND_QUERY)); 469 ec->nr_pending_queries++; 470 schedule_work(&ec->work); 471 } 472 } 473 474 static void acpi_ec_complete_query(struct acpi_ec *ec) 475 { 476 if (test_and_clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags)) 477 ec_dbg_evt("Command(%s) unblocked", 478 acpi_ec_cmd_string(ACPI_EC_COMMAND_QUERY)); 479 acpi_ec_clear_storm(ec, EC_FLAGS_COMMAND_STORM); 480 } 481 482 static inline void __acpi_ec_enable_event(struct acpi_ec *ec) 483 { 484 if (!test_and_set_bit(EC_FLAGS_QUERY_ENABLED, &ec->flags)) 485 ec_log_drv("event unblocked"); 486 if (!test_bit(EC_FLAGS_QUERY_PENDING, &ec->flags)) 487 advance_transaction(ec); 488 } 489 490 static inline void __acpi_ec_disable_event(struct acpi_ec *ec) 491 { 492 if (test_and_clear_bit(EC_FLAGS_QUERY_ENABLED, &ec->flags)) 493 ec_log_drv("event blocked"); 494 } 495 496 static void acpi_ec_enable_event(struct acpi_ec *ec) 497 { 498 unsigned long flags; 499 500 spin_lock_irqsave(&ec->lock, flags); 501 if (acpi_ec_started(ec)) 502 __acpi_ec_enable_event(ec); 503 spin_unlock_irqrestore(&ec->lock, flags); 504 } 505 506 #ifdef CONFIG_PM_SLEEP 507 static bool acpi_ec_query_flushed(struct acpi_ec *ec) 508 { 509 bool flushed; 510 unsigned long flags; 511 512 spin_lock_irqsave(&ec->lock, flags); 513 flushed = !ec->nr_pending_queries; 514 spin_unlock_irqrestore(&ec->lock, flags); 515 return flushed; 516 } 517 518 static void __acpi_ec_flush_event(struct acpi_ec *ec) 519 { 520 /* 521 * When ec_freeze_events is true, we need to flush events in 522 * the proper position before entering the noirq stage. 523 */ 524 wait_event(ec->wait, acpi_ec_query_flushed(ec)); 525 if (ec_query_wq) 526 flush_workqueue(ec_query_wq); 527 } 528 529 static void acpi_ec_disable_event(struct acpi_ec *ec) 530 { 531 unsigned long flags; 532 533 spin_lock_irqsave(&ec->lock, flags); 534 __acpi_ec_disable_event(ec); 535 spin_unlock_irqrestore(&ec->lock, flags); 536 __acpi_ec_flush_event(ec); 537 } 538 #endif /* CONFIG_PM_SLEEP */ 539 540 static bool acpi_ec_guard_event(struct acpi_ec *ec) 541 { 542 bool guarded = true; 543 unsigned long flags; 544 545 spin_lock_irqsave(&ec->lock, flags); 546 /* 547 * If firmware SCI_EVT clearing timing is "event", we actually 548 * don't know when the SCI_EVT will be cleared by firmware after 549 * evaluating _Qxx, so we need to re-check SCI_EVT after waiting an 550 * acceptable period. 551 * 552 * The guarding period begins when EC_FLAGS_QUERY_PENDING is 553 * flagged, which means SCI_EVT check has just been performed. 554 * But if the current transaction is ACPI_EC_COMMAND_QUERY, the 555 * guarding should have already been performed (via 556 * EC_FLAGS_QUERY_GUARDING) and should not be applied so that the 557 * ACPI_EC_COMMAND_QUERY transaction can be transitioned into 558 * ACPI_EC_COMMAND_POLL state immediately. 559 */ 560 if (ec_event_clearing == ACPI_EC_EVT_TIMING_STATUS || 561 ec_event_clearing == ACPI_EC_EVT_TIMING_QUERY || 562 !test_bit(EC_FLAGS_QUERY_PENDING, &ec->flags) || 563 (ec->curr && ec->curr->command == ACPI_EC_COMMAND_QUERY)) 564 guarded = false; 565 spin_unlock_irqrestore(&ec->lock, flags); 566 return guarded; 567 } 568 569 static int ec_transaction_polled(struct acpi_ec *ec) 570 { 571 unsigned long flags; 572 int ret = 0; 573 574 spin_lock_irqsave(&ec->lock, flags); 575 if (ec->curr && (ec->curr->flags & ACPI_EC_COMMAND_POLL)) 576 ret = 1; 577 spin_unlock_irqrestore(&ec->lock, flags); 578 return ret; 579 } 580 581 static int ec_transaction_completed(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_COMPLETE)) 588 ret = 1; 589 spin_unlock_irqrestore(&ec->lock, flags); 590 return ret; 591 } 592 593 static inline void ec_transaction_transition(struct acpi_ec *ec, unsigned long flag) 594 { 595 ec->curr->flags |= flag; 596 if (ec->curr->command == ACPI_EC_COMMAND_QUERY) { 597 if (ec_event_clearing == ACPI_EC_EVT_TIMING_STATUS && 598 flag == ACPI_EC_COMMAND_POLL) 599 acpi_ec_complete_query(ec); 600 if (ec_event_clearing == ACPI_EC_EVT_TIMING_QUERY && 601 flag == ACPI_EC_COMMAND_COMPLETE) 602 acpi_ec_complete_query(ec); 603 if (ec_event_clearing == ACPI_EC_EVT_TIMING_EVENT && 604 flag == ACPI_EC_COMMAND_COMPLETE) 605 set_bit(EC_FLAGS_QUERY_GUARDING, &ec->flags); 606 } 607 } 608 609 static void advance_transaction(struct acpi_ec *ec) 610 { 611 struct transaction *t; 612 u8 status; 613 bool wakeup = false; 614 615 ec_dbg_stm("%s (%d)", in_interrupt() ? "IRQ" : "TASK", 616 smp_processor_id()); 617 /* 618 * By always clearing STS before handling all indications, we can 619 * ensure a hardware STS 0->1 change after this clearing can always 620 * trigger a GPE interrupt. 621 */ 622 acpi_ec_clear_gpe(ec); 623 status = acpi_ec_read_status(ec); 624 t = ec->curr; 625 /* 626 * Another IRQ or a guarded polling mode advancement is detected, 627 * the next QR_EC submission is then allowed. 628 */ 629 if (!t || !(t->flags & ACPI_EC_COMMAND_POLL)) { 630 if (ec_event_clearing == ACPI_EC_EVT_TIMING_EVENT && 631 (!ec->nr_pending_queries || 632 test_bit(EC_FLAGS_QUERY_GUARDING, &ec->flags))) { 633 clear_bit(EC_FLAGS_QUERY_GUARDING, &ec->flags); 634 acpi_ec_complete_query(ec); 635 } 636 } 637 if (!t) 638 goto err; 639 if (t->flags & ACPI_EC_COMMAND_POLL) { 640 if (t->wlen > t->wi) { 641 if ((status & ACPI_EC_FLAG_IBF) == 0) 642 acpi_ec_write_data(ec, t->wdata[t->wi++]); 643 else 644 goto err; 645 } else if (t->rlen > t->ri) { 646 if ((status & ACPI_EC_FLAG_OBF) == 1) { 647 t->rdata[t->ri++] = acpi_ec_read_data(ec); 648 if (t->rlen == t->ri) { 649 ec_transaction_transition(ec, ACPI_EC_COMMAND_COMPLETE); 650 if (t->command == ACPI_EC_COMMAND_QUERY) 651 ec_dbg_evt("Command(%s) completed by hardware", 652 acpi_ec_cmd_string(ACPI_EC_COMMAND_QUERY)); 653 wakeup = true; 654 } 655 } else 656 goto err; 657 } else if (t->wlen == t->wi && 658 (status & ACPI_EC_FLAG_IBF) == 0) { 659 ec_transaction_transition(ec, ACPI_EC_COMMAND_COMPLETE); 660 wakeup = true; 661 } 662 goto out; 663 } else { 664 if (EC_FLAGS_QUERY_HANDSHAKE && 665 !(status & ACPI_EC_FLAG_SCI) && 666 (t->command == ACPI_EC_COMMAND_QUERY)) { 667 ec_transaction_transition(ec, ACPI_EC_COMMAND_POLL); 668 t->rdata[t->ri++] = 0x00; 669 ec_transaction_transition(ec, ACPI_EC_COMMAND_COMPLETE); 670 ec_dbg_evt("Command(%s) completed by software", 671 acpi_ec_cmd_string(ACPI_EC_COMMAND_QUERY)); 672 wakeup = true; 673 } else if ((status & ACPI_EC_FLAG_IBF) == 0) { 674 acpi_ec_write_cmd(ec, t->command); 675 ec_transaction_transition(ec, ACPI_EC_COMMAND_POLL); 676 } else 677 goto err; 678 goto out; 679 } 680 err: 681 /* 682 * If SCI bit is set, then don't think it's a false IRQ 683 * otherwise will take a not handled IRQ as a false one. 684 */ 685 if (!(status & ACPI_EC_FLAG_SCI)) { 686 if (in_interrupt() && t) { 687 if (t->irq_count < ec_storm_threshold) 688 ++t->irq_count; 689 /* Allow triggering on 0 threshold */ 690 if (t->irq_count == ec_storm_threshold) 691 acpi_ec_set_storm(ec, EC_FLAGS_COMMAND_STORM); 692 } 693 } 694 out: 695 if (status & ACPI_EC_FLAG_SCI) 696 acpi_ec_submit_query(ec); 697 if (wakeup && in_interrupt()) 698 wake_up(&ec->wait); 699 } 700 701 static void start_transaction(struct acpi_ec *ec) 702 { 703 ec->curr->irq_count = ec->curr->wi = ec->curr->ri = 0; 704 ec->curr->flags = 0; 705 } 706 707 static int ec_guard(struct acpi_ec *ec) 708 { 709 unsigned long guard = usecs_to_jiffies(ec->polling_guard); 710 unsigned long timeout = ec->timestamp + guard; 711 712 /* Ensure guarding period before polling EC status */ 713 do { 714 if (ec->busy_polling) { 715 /* Perform busy polling */ 716 if (ec_transaction_completed(ec)) 717 return 0; 718 udelay(jiffies_to_usecs(guard)); 719 } else { 720 /* 721 * Perform wait polling 722 * 1. Wait the transaction to be completed by the 723 * GPE handler after the transaction enters 724 * ACPI_EC_COMMAND_POLL state. 725 * 2. A special guarding logic is also required 726 * for event clearing mode "event" before the 727 * transaction enters ACPI_EC_COMMAND_POLL 728 * state. 729 */ 730 if (!ec_transaction_polled(ec) && 731 !acpi_ec_guard_event(ec)) 732 break; 733 if (wait_event_timeout(ec->wait, 734 ec_transaction_completed(ec), 735 guard)) 736 return 0; 737 } 738 } while (time_before(jiffies, timeout)); 739 return -ETIME; 740 } 741 742 static int ec_poll(struct acpi_ec *ec) 743 { 744 unsigned long flags; 745 int repeat = 5; /* number of command restarts */ 746 747 while (repeat--) { 748 unsigned long delay = jiffies + 749 msecs_to_jiffies(ec_delay); 750 do { 751 if (!ec_guard(ec)) 752 return 0; 753 spin_lock_irqsave(&ec->lock, flags); 754 advance_transaction(ec); 755 spin_unlock_irqrestore(&ec->lock, flags); 756 } while (time_before(jiffies, delay)); 757 pr_debug("controller reset, restart transaction\n"); 758 spin_lock_irqsave(&ec->lock, flags); 759 start_transaction(ec); 760 spin_unlock_irqrestore(&ec->lock, flags); 761 } 762 return -ETIME; 763 } 764 765 static int acpi_ec_transaction_unlocked(struct acpi_ec *ec, 766 struct transaction *t) 767 { 768 unsigned long tmp; 769 int ret = 0; 770 771 /* start transaction */ 772 spin_lock_irqsave(&ec->lock, tmp); 773 /* Enable GPE for command processing (IBF=0/OBF=1) */ 774 if (!acpi_ec_submit_flushable_request(ec)) { 775 ret = -EINVAL; 776 goto unlock; 777 } 778 ec_dbg_ref(ec, "Increase command"); 779 /* following two actions should be kept atomic */ 780 ec->curr = t; 781 ec_dbg_req("Command(%s) started", acpi_ec_cmd_string(t->command)); 782 start_transaction(ec); 783 spin_unlock_irqrestore(&ec->lock, tmp); 784 785 ret = ec_poll(ec); 786 787 spin_lock_irqsave(&ec->lock, tmp); 788 if (t->irq_count == ec_storm_threshold) 789 acpi_ec_clear_storm(ec, EC_FLAGS_COMMAND_STORM); 790 ec_dbg_req("Command(%s) stopped", acpi_ec_cmd_string(t->command)); 791 ec->curr = NULL; 792 /* Disable GPE for command processing (IBF=0/OBF=1) */ 793 acpi_ec_complete_request(ec); 794 ec_dbg_ref(ec, "Decrease command"); 795 unlock: 796 spin_unlock_irqrestore(&ec->lock, tmp); 797 return ret; 798 } 799 800 static int acpi_ec_transaction(struct acpi_ec *ec, struct transaction *t) 801 { 802 int status; 803 u32 glk; 804 805 if (!ec || (!t) || (t->wlen && !t->wdata) || (t->rlen && !t->rdata)) 806 return -EINVAL; 807 if (t->rdata) 808 memset(t->rdata, 0, t->rlen); 809 810 mutex_lock(&ec->mutex); 811 if (ec->global_lock) { 812 status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk); 813 if (ACPI_FAILURE(status)) { 814 status = -ENODEV; 815 goto unlock; 816 } 817 } 818 819 status = acpi_ec_transaction_unlocked(ec, t); 820 821 if (ec->global_lock) 822 acpi_release_global_lock(glk); 823 unlock: 824 mutex_unlock(&ec->mutex); 825 return status; 826 } 827 828 static int acpi_ec_burst_enable(struct acpi_ec *ec) 829 { 830 u8 d; 831 struct transaction t = {.command = ACPI_EC_BURST_ENABLE, 832 .wdata = NULL, .rdata = &d, 833 .wlen = 0, .rlen = 1}; 834 835 return acpi_ec_transaction(ec, &t); 836 } 837 838 static int acpi_ec_burst_disable(struct acpi_ec *ec) 839 { 840 struct transaction t = {.command = ACPI_EC_BURST_DISABLE, 841 .wdata = NULL, .rdata = NULL, 842 .wlen = 0, .rlen = 0}; 843 844 return (acpi_ec_read_status(ec) & ACPI_EC_FLAG_BURST) ? 845 acpi_ec_transaction(ec, &t) : 0; 846 } 847 848 static int acpi_ec_read(struct acpi_ec *ec, u8 address, u8 *data) 849 { 850 int result; 851 u8 d; 852 struct transaction t = {.command = ACPI_EC_COMMAND_READ, 853 .wdata = &address, .rdata = &d, 854 .wlen = 1, .rlen = 1}; 855 856 result = acpi_ec_transaction(ec, &t); 857 *data = d; 858 return result; 859 } 860 861 static int acpi_ec_write(struct acpi_ec *ec, u8 address, u8 data) 862 { 863 u8 wdata[2] = { address, data }; 864 struct transaction t = {.command = ACPI_EC_COMMAND_WRITE, 865 .wdata = wdata, .rdata = NULL, 866 .wlen = 2, .rlen = 0}; 867 868 return acpi_ec_transaction(ec, &t); 869 } 870 871 int ec_read(u8 addr, u8 *val) 872 { 873 int err; 874 u8 temp_data; 875 876 if (!first_ec) 877 return -ENODEV; 878 879 err = acpi_ec_read(first_ec, addr, &temp_data); 880 881 if (!err) { 882 *val = temp_data; 883 return 0; 884 } 885 return err; 886 } 887 EXPORT_SYMBOL(ec_read); 888 889 int ec_write(u8 addr, u8 val) 890 { 891 int err; 892 893 if (!first_ec) 894 return -ENODEV; 895 896 err = acpi_ec_write(first_ec, addr, val); 897 898 return err; 899 } 900 EXPORT_SYMBOL(ec_write); 901 902 int ec_transaction(u8 command, 903 const u8 *wdata, unsigned wdata_len, 904 u8 *rdata, unsigned rdata_len) 905 { 906 struct transaction t = {.command = command, 907 .wdata = wdata, .rdata = rdata, 908 .wlen = wdata_len, .rlen = rdata_len}; 909 910 if (!first_ec) 911 return -ENODEV; 912 913 return acpi_ec_transaction(first_ec, &t); 914 } 915 EXPORT_SYMBOL(ec_transaction); 916 917 /* Get the handle to the EC device */ 918 acpi_handle ec_get_handle(void) 919 { 920 if (!first_ec) 921 return NULL; 922 return first_ec->handle; 923 } 924 EXPORT_SYMBOL(ec_get_handle); 925 926 static void acpi_ec_start(struct acpi_ec *ec, bool resuming) 927 { 928 unsigned long flags; 929 930 spin_lock_irqsave(&ec->lock, flags); 931 if (!test_and_set_bit(EC_FLAGS_STARTED, &ec->flags)) { 932 ec_dbg_drv("Starting EC"); 933 /* Enable GPE for event processing (SCI_EVT=1) */ 934 if (!resuming) { 935 acpi_ec_submit_request(ec); 936 ec_dbg_ref(ec, "Increase driver"); 937 } 938 ec_log_drv("EC started"); 939 } 940 spin_unlock_irqrestore(&ec->lock, flags); 941 } 942 943 static bool acpi_ec_stopped(struct acpi_ec *ec) 944 { 945 unsigned long flags; 946 bool flushed; 947 948 spin_lock_irqsave(&ec->lock, flags); 949 flushed = acpi_ec_flushed(ec); 950 spin_unlock_irqrestore(&ec->lock, flags); 951 return flushed; 952 } 953 954 static void acpi_ec_stop(struct acpi_ec *ec, bool suspending) 955 { 956 unsigned long flags; 957 958 spin_lock_irqsave(&ec->lock, flags); 959 if (acpi_ec_started(ec)) { 960 ec_dbg_drv("Stopping EC"); 961 set_bit(EC_FLAGS_STOPPED, &ec->flags); 962 spin_unlock_irqrestore(&ec->lock, flags); 963 wait_event(ec->wait, acpi_ec_stopped(ec)); 964 spin_lock_irqsave(&ec->lock, flags); 965 /* Disable GPE for event processing (SCI_EVT=1) */ 966 if (!suspending) { 967 acpi_ec_complete_request(ec); 968 ec_dbg_ref(ec, "Decrease driver"); 969 } else if (!ec_freeze_events) 970 __acpi_ec_disable_event(ec); 971 clear_bit(EC_FLAGS_STARTED, &ec->flags); 972 clear_bit(EC_FLAGS_STOPPED, &ec->flags); 973 ec_log_drv("EC stopped"); 974 } 975 spin_unlock_irqrestore(&ec->lock, flags); 976 } 977 978 static void acpi_ec_enter_noirq(struct acpi_ec *ec) 979 { 980 unsigned long flags; 981 982 spin_lock_irqsave(&ec->lock, flags); 983 ec->busy_polling = true; 984 ec->polling_guard = 0; 985 ec_log_drv("interrupt blocked"); 986 spin_unlock_irqrestore(&ec->lock, flags); 987 } 988 989 static void acpi_ec_leave_noirq(struct acpi_ec *ec) 990 { 991 unsigned long flags; 992 993 spin_lock_irqsave(&ec->lock, flags); 994 ec->busy_polling = ec_busy_polling; 995 ec->polling_guard = ec_polling_guard; 996 ec_log_drv("interrupt unblocked"); 997 spin_unlock_irqrestore(&ec->lock, flags); 998 } 999 1000 void acpi_ec_block_transactions(void) 1001 { 1002 struct acpi_ec *ec = first_ec; 1003 1004 if (!ec) 1005 return; 1006 1007 mutex_lock(&ec->mutex); 1008 /* Prevent transactions from being carried out */ 1009 acpi_ec_stop(ec, true); 1010 mutex_unlock(&ec->mutex); 1011 } 1012 1013 void acpi_ec_unblock_transactions(void) 1014 { 1015 /* 1016 * Allow transactions to happen again (this function is called from 1017 * atomic context during wakeup, so we don't need to acquire the mutex). 1018 */ 1019 if (first_ec) 1020 acpi_ec_start(first_ec, true); 1021 } 1022 1023 /* -------------------------------------------------------------------------- 1024 Event Management 1025 -------------------------------------------------------------------------- */ 1026 static struct acpi_ec_query_handler * 1027 acpi_ec_get_query_handler(struct acpi_ec_query_handler *handler) 1028 { 1029 if (handler) 1030 kref_get(&handler->kref); 1031 return handler; 1032 } 1033 1034 static struct acpi_ec_query_handler * 1035 acpi_ec_get_query_handler_by_value(struct acpi_ec *ec, u8 value) 1036 { 1037 struct acpi_ec_query_handler *handler; 1038 bool found = false; 1039 1040 mutex_lock(&ec->mutex); 1041 list_for_each_entry(handler, &ec->list, node) { 1042 if (value == handler->query_bit) { 1043 found = true; 1044 break; 1045 } 1046 } 1047 mutex_unlock(&ec->mutex); 1048 return found ? acpi_ec_get_query_handler(handler) : NULL; 1049 } 1050 1051 static void acpi_ec_query_handler_release(struct kref *kref) 1052 { 1053 struct acpi_ec_query_handler *handler = 1054 container_of(kref, struct acpi_ec_query_handler, kref); 1055 1056 kfree(handler); 1057 } 1058 1059 static void acpi_ec_put_query_handler(struct acpi_ec_query_handler *handler) 1060 { 1061 kref_put(&handler->kref, acpi_ec_query_handler_release); 1062 } 1063 1064 int acpi_ec_add_query_handler(struct acpi_ec *ec, u8 query_bit, 1065 acpi_handle handle, acpi_ec_query_func func, 1066 void *data) 1067 { 1068 struct acpi_ec_query_handler *handler = 1069 kzalloc(sizeof(struct acpi_ec_query_handler), GFP_KERNEL); 1070 1071 if (!handler) 1072 return -ENOMEM; 1073 1074 handler->query_bit = query_bit; 1075 handler->handle = handle; 1076 handler->func = func; 1077 handler->data = data; 1078 mutex_lock(&ec->mutex); 1079 kref_init(&handler->kref); 1080 list_add(&handler->node, &ec->list); 1081 mutex_unlock(&ec->mutex); 1082 return 0; 1083 } 1084 EXPORT_SYMBOL_GPL(acpi_ec_add_query_handler); 1085 1086 static void acpi_ec_remove_query_handlers(struct acpi_ec *ec, 1087 bool remove_all, u8 query_bit) 1088 { 1089 struct acpi_ec_query_handler *handler, *tmp; 1090 LIST_HEAD(free_list); 1091 1092 mutex_lock(&ec->mutex); 1093 list_for_each_entry_safe(handler, tmp, &ec->list, node) { 1094 if (remove_all || query_bit == handler->query_bit) { 1095 list_del_init(&handler->node); 1096 list_add(&handler->node, &free_list); 1097 } 1098 } 1099 mutex_unlock(&ec->mutex); 1100 list_for_each_entry_safe(handler, tmp, &free_list, node) 1101 acpi_ec_put_query_handler(handler); 1102 } 1103 1104 void acpi_ec_remove_query_handler(struct acpi_ec *ec, u8 query_bit) 1105 { 1106 acpi_ec_remove_query_handlers(ec, false, query_bit); 1107 } 1108 EXPORT_SYMBOL_GPL(acpi_ec_remove_query_handler); 1109 1110 static struct acpi_ec_query *acpi_ec_create_query(u8 *pval) 1111 { 1112 struct acpi_ec_query *q; 1113 struct transaction *t; 1114 1115 q = kzalloc(sizeof (struct acpi_ec_query), GFP_KERNEL); 1116 if (!q) 1117 return NULL; 1118 INIT_WORK(&q->work, acpi_ec_event_processor); 1119 t = &q->transaction; 1120 t->command = ACPI_EC_COMMAND_QUERY; 1121 t->rdata = pval; 1122 t->rlen = 1; 1123 return q; 1124 } 1125 1126 static void acpi_ec_delete_query(struct acpi_ec_query *q) 1127 { 1128 if (q) { 1129 if (q->handler) 1130 acpi_ec_put_query_handler(q->handler); 1131 kfree(q); 1132 } 1133 } 1134 1135 static void acpi_ec_event_processor(struct work_struct *work) 1136 { 1137 struct acpi_ec_query *q = container_of(work, struct acpi_ec_query, work); 1138 struct acpi_ec_query_handler *handler = q->handler; 1139 1140 ec_dbg_evt("Query(0x%02x) started", handler->query_bit); 1141 if (handler->func) 1142 handler->func(handler->data); 1143 else if (handler->handle) 1144 acpi_evaluate_object(handler->handle, NULL, NULL, NULL); 1145 ec_dbg_evt("Query(0x%02x) stopped", handler->query_bit); 1146 acpi_ec_delete_query(q); 1147 } 1148 1149 static int acpi_ec_query(struct acpi_ec *ec, u8 *data) 1150 { 1151 u8 value = 0; 1152 int result; 1153 struct acpi_ec_query *q; 1154 1155 q = acpi_ec_create_query(&value); 1156 if (!q) 1157 return -ENOMEM; 1158 1159 /* 1160 * Query the EC to find out which _Qxx method we need to evaluate. 1161 * Note that successful completion of the query causes the ACPI_EC_SCI 1162 * bit to be cleared (and thus clearing the interrupt source). 1163 */ 1164 result = acpi_ec_transaction(ec, &q->transaction); 1165 if (!value) 1166 result = -ENODATA; 1167 if (result) 1168 goto err_exit; 1169 1170 q->handler = acpi_ec_get_query_handler_by_value(ec, value); 1171 if (!q->handler) { 1172 result = -ENODATA; 1173 goto err_exit; 1174 } 1175 1176 /* 1177 * It is reported that _Qxx are evaluated in a parallel way on 1178 * Windows: 1179 * https://bugzilla.kernel.org/show_bug.cgi?id=94411 1180 * 1181 * Put this log entry before schedule_work() in order to make 1182 * it appearing before any other log entries occurred during the 1183 * work queue execution. 1184 */ 1185 ec_dbg_evt("Query(0x%02x) scheduled", value); 1186 if (!queue_work(ec_query_wq, &q->work)) { 1187 ec_dbg_evt("Query(0x%02x) overlapped", value); 1188 result = -EBUSY; 1189 } 1190 1191 err_exit: 1192 if (result) 1193 acpi_ec_delete_query(q); 1194 if (data) 1195 *data = value; 1196 return result; 1197 } 1198 1199 static void acpi_ec_check_event(struct acpi_ec *ec) 1200 { 1201 unsigned long flags; 1202 1203 if (ec_event_clearing == ACPI_EC_EVT_TIMING_EVENT) { 1204 if (ec_guard(ec)) { 1205 spin_lock_irqsave(&ec->lock, flags); 1206 /* 1207 * Take care of the SCI_EVT unless no one else is 1208 * taking care of it. 1209 */ 1210 if (!ec->curr) 1211 advance_transaction(ec); 1212 spin_unlock_irqrestore(&ec->lock, flags); 1213 } 1214 } 1215 } 1216 1217 static void acpi_ec_event_handler(struct work_struct *work) 1218 { 1219 unsigned long flags; 1220 struct acpi_ec *ec = container_of(work, struct acpi_ec, work); 1221 1222 ec_dbg_evt("Event started"); 1223 1224 spin_lock_irqsave(&ec->lock, flags); 1225 while (ec->nr_pending_queries) { 1226 spin_unlock_irqrestore(&ec->lock, flags); 1227 (void)acpi_ec_query(ec, NULL); 1228 spin_lock_irqsave(&ec->lock, flags); 1229 ec->nr_pending_queries--; 1230 /* 1231 * Before exit, make sure that this work item can be 1232 * scheduled again. There might be QR_EC failures, leaving 1233 * EC_FLAGS_QUERY_PENDING uncleared and preventing this work 1234 * item from being scheduled again. 1235 */ 1236 if (!ec->nr_pending_queries) { 1237 if (ec_event_clearing == ACPI_EC_EVT_TIMING_STATUS || 1238 ec_event_clearing == ACPI_EC_EVT_TIMING_QUERY) 1239 acpi_ec_complete_query(ec); 1240 } 1241 } 1242 spin_unlock_irqrestore(&ec->lock, flags); 1243 1244 ec_dbg_evt("Event stopped"); 1245 1246 acpi_ec_check_event(ec); 1247 } 1248 1249 static u32 acpi_ec_gpe_handler(acpi_handle gpe_device, 1250 u32 gpe_number, void *data) 1251 { 1252 unsigned long flags; 1253 struct acpi_ec *ec = data; 1254 1255 spin_lock_irqsave(&ec->lock, flags); 1256 advance_transaction(ec); 1257 spin_unlock_irqrestore(&ec->lock, flags); 1258 return ACPI_INTERRUPT_HANDLED; 1259 } 1260 1261 /* -------------------------------------------------------------------------- 1262 * Address Space Management 1263 * -------------------------------------------------------------------------- */ 1264 1265 static acpi_status 1266 acpi_ec_space_handler(u32 function, acpi_physical_address address, 1267 u32 bits, u64 *value64, 1268 void *handler_context, void *region_context) 1269 { 1270 struct acpi_ec *ec = handler_context; 1271 int result = 0, i, bytes = bits / 8; 1272 u8 *value = (u8 *)value64; 1273 1274 if ((address > 0xFF) || !value || !handler_context) 1275 return AE_BAD_PARAMETER; 1276 1277 if (function != ACPI_READ && function != ACPI_WRITE) 1278 return AE_BAD_PARAMETER; 1279 1280 if (ec->busy_polling || bits > 8) 1281 acpi_ec_burst_enable(ec); 1282 1283 for (i = 0; i < bytes; ++i, ++address, ++value) 1284 result = (function == ACPI_READ) ? 1285 acpi_ec_read(ec, address, value) : 1286 acpi_ec_write(ec, address, *value); 1287 1288 if (ec->busy_polling || bits > 8) 1289 acpi_ec_burst_disable(ec); 1290 1291 switch (result) { 1292 case -EINVAL: 1293 return AE_BAD_PARAMETER; 1294 case -ENODEV: 1295 return AE_NOT_FOUND; 1296 case -ETIME: 1297 return AE_TIME; 1298 default: 1299 return AE_OK; 1300 } 1301 } 1302 1303 /* -------------------------------------------------------------------------- 1304 * Driver Interface 1305 * -------------------------------------------------------------------------- */ 1306 1307 static acpi_status 1308 ec_parse_io_ports(struct acpi_resource *resource, void *context); 1309 1310 static void acpi_ec_free(struct acpi_ec *ec) 1311 { 1312 if (first_ec == ec) 1313 first_ec = NULL; 1314 if (boot_ec == ec) 1315 boot_ec = NULL; 1316 kfree(ec); 1317 } 1318 1319 static struct acpi_ec *acpi_ec_alloc(void) 1320 { 1321 struct acpi_ec *ec = kzalloc(sizeof(struct acpi_ec), GFP_KERNEL); 1322 1323 if (!ec) 1324 return NULL; 1325 mutex_init(&ec->mutex); 1326 init_waitqueue_head(&ec->wait); 1327 INIT_LIST_HEAD(&ec->list); 1328 spin_lock_init(&ec->lock); 1329 INIT_WORK(&ec->work, acpi_ec_event_handler); 1330 ec->timestamp = jiffies; 1331 ec->busy_polling = true; 1332 ec->polling_guard = 0; 1333 return ec; 1334 } 1335 1336 static acpi_status 1337 acpi_ec_register_query_methods(acpi_handle handle, u32 level, 1338 void *context, void **return_value) 1339 { 1340 char node_name[5]; 1341 struct acpi_buffer buffer = { sizeof(node_name), node_name }; 1342 struct acpi_ec *ec = context; 1343 int value = 0; 1344 acpi_status status; 1345 1346 status = acpi_get_name(handle, ACPI_SINGLE_NAME, &buffer); 1347 1348 if (ACPI_SUCCESS(status) && sscanf(node_name, "_Q%x", &value) == 1) 1349 acpi_ec_add_query_handler(ec, value, handle, NULL, NULL); 1350 return AE_OK; 1351 } 1352 1353 static acpi_status 1354 ec_parse_device(acpi_handle handle, u32 Level, void *context, void **retval) 1355 { 1356 acpi_status status; 1357 unsigned long long tmp = 0; 1358 struct acpi_ec *ec = context; 1359 1360 /* clear addr values, ec_parse_io_ports depend on it */ 1361 ec->command_addr = ec->data_addr = 0; 1362 1363 status = acpi_walk_resources(handle, METHOD_NAME__CRS, 1364 ec_parse_io_ports, ec); 1365 if (ACPI_FAILURE(status)) 1366 return status; 1367 if (ec->data_addr == 0 || ec->command_addr == 0) 1368 return AE_OK; 1369 1370 if (boot_ec && boot_ec_is_ecdt && EC_FLAGS_IGNORE_DSDT_GPE) { 1371 /* 1372 * Always inherit the GPE number setting from the ECDT 1373 * EC. 1374 */ 1375 ec->gpe = boot_ec->gpe; 1376 } else { 1377 /* Get GPE bit assignment (EC events). */ 1378 /* TODO: Add support for _GPE returning a package */ 1379 status = acpi_evaluate_integer(handle, "_GPE", NULL, &tmp); 1380 if (ACPI_FAILURE(status)) 1381 return status; 1382 ec->gpe = tmp; 1383 } 1384 /* Use the global lock for all EC transactions? */ 1385 tmp = 0; 1386 acpi_evaluate_integer(handle, "_GLK", NULL, &tmp); 1387 ec->global_lock = tmp; 1388 ec->handle = handle; 1389 return AE_CTRL_TERMINATE; 1390 } 1391 1392 /* 1393 * Note: This function returns an error code only when the address space 1394 * handler is not installed, which means "not able to handle 1395 * transactions". 1396 */ 1397 static int ec_install_handlers(struct acpi_ec *ec, bool handle_events) 1398 { 1399 acpi_status status; 1400 1401 acpi_ec_start(ec, false); 1402 1403 if (!test_bit(EC_FLAGS_EC_HANDLER_INSTALLED, &ec->flags)) { 1404 acpi_ec_enter_noirq(ec); 1405 status = acpi_install_address_space_handler(ec->handle, 1406 ACPI_ADR_SPACE_EC, 1407 &acpi_ec_space_handler, 1408 NULL, ec); 1409 if (ACPI_FAILURE(status)) { 1410 if (status == AE_NOT_FOUND) { 1411 /* 1412 * Maybe OS fails in evaluating the _REG 1413 * object. The AE_NOT_FOUND error will be 1414 * ignored and OS * continue to initialize 1415 * EC. 1416 */ 1417 pr_err("Fail in evaluating the _REG object" 1418 " of EC device. Broken bios is suspected.\n"); 1419 } else { 1420 acpi_ec_stop(ec, false); 1421 return -ENODEV; 1422 } 1423 } 1424 set_bit(EC_FLAGS_EC_HANDLER_INSTALLED, &ec->flags); 1425 } 1426 1427 if (!handle_events) 1428 return 0; 1429 1430 if (!test_bit(EC_FLAGS_EVT_HANDLER_INSTALLED, &ec->flags)) { 1431 /* Find and register all query methods */ 1432 acpi_walk_namespace(ACPI_TYPE_METHOD, ec->handle, 1, 1433 acpi_ec_register_query_methods, 1434 NULL, ec, NULL); 1435 set_bit(EC_FLAGS_EVT_HANDLER_INSTALLED, &ec->flags); 1436 } 1437 if (!test_bit(EC_FLAGS_GPE_HANDLER_INSTALLED, &ec->flags)) { 1438 status = acpi_install_gpe_raw_handler(NULL, ec->gpe, 1439 ACPI_GPE_EDGE_TRIGGERED, 1440 &acpi_ec_gpe_handler, ec); 1441 /* This is not fatal as we can poll EC events */ 1442 if (ACPI_SUCCESS(status)) { 1443 set_bit(EC_FLAGS_GPE_HANDLER_INSTALLED, &ec->flags); 1444 acpi_ec_leave_noirq(ec); 1445 if (test_bit(EC_FLAGS_STARTED, &ec->flags) && 1446 ec->reference_count >= 1) 1447 acpi_ec_enable_gpe(ec, true); 1448 1449 /* EC is fully operational, allow queries */ 1450 acpi_ec_enable_event(ec); 1451 } 1452 } 1453 1454 return 0; 1455 } 1456 1457 static void ec_remove_handlers(struct acpi_ec *ec) 1458 { 1459 if (test_bit(EC_FLAGS_EC_HANDLER_INSTALLED, &ec->flags)) { 1460 if (ACPI_FAILURE(acpi_remove_address_space_handler(ec->handle, 1461 ACPI_ADR_SPACE_EC, &acpi_ec_space_handler))) 1462 pr_err("failed to remove space handler\n"); 1463 clear_bit(EC_FLAGS_EC_HANDLER_INSTALLED, &ec->flags); 1464 } 1465 1466 /* 1467 * Stops handling the EC transactions after removing the operation 1468 * region handler. This is required because _REG(DISCONNECT) 1469 * invoked during the removal can result in new EC transactions. 1470 * 1471 * Flushes the EC requests and thus disables the GPE before 1472 * removing the GPE handler. This is required by the current ACPICA 1473 * GPE core. ACPICA GPE core will automatically disable a GPE when 1474 * it is indicated but there is no way to handle it. So the drivers 1475 * must disable the GPEs prior to removing the GPE handlers. 1476 */ 1477 acpi_ec_stop(ec, false); 1478 1479 if (test_bit(EC_FLAGS_GPE_HANDLER_INSTALLED, &ec->flags)) { 1480 if (ACPI_FAILURE(acpi_remove_gpe_handler(NULL, ec->gpe, 1481 &acpi_ec_gpe_handler))) 1482 pr_err("failed to remove gpe handler\n"); 1483 clear_bit(EC_FLAGS_GPE_HANDLER_INSTALLED, &ec->flags); 1484 } 1485 if (test_bit(EC_FLAGS_EVT_HANDLER_INSTALLED, &ec->flags)) { 1486 acpi_ec_remove_query_handlers(ec, true, 0); 1487 clear_bit(EC_FLAGS_EVT_HANDLER_INSTALLED, &ec->flags); 1488 } 1489 } 1490 1491 static int acpi_ec_setup(struct acpi_ec *ec, bool handle_events) 1492 { 1493 int ret; 1494 1495 ret = ec_install_handlers(ec, handle_events); 1496 if (ret) 1497 return ret; 1498 1499 /* First EC capable of handling transactions */ 1500 if (!first_ec) { 1501 first_ec = ec; 1502 acpi_handle_info(first_ec->handle, "Used as first EC\n"); 1503 } 1504 1505 acpi_handle_info(ec->handle, 1506 "GPE=0x%lx, EC_CMD/EC_SC=0x%lx, EC_DATA=0x%lx\n", 1507 ec->gpe, ec->command_addr, ec->data_addr); 1508 return ret; 1509 } 1510 1511 static int acpi_config_boot_ec(struct acpi_ec *ec, acpi_handle handle, 1512 bool handle_events, bool is_ecdt) 1513 { 1514 int ret; 1515 1516 /* 1517 * Changing the ACPI handle results in a re-configuration of the 1518 * boot EC. And if it happens after the namespace initialization, 1519 * it causes _REG evaluations. 1520 */ 1521 if (boot_ec && boot_ec->handle != handle) 1522 ec_remove_handlers(boot_ec); 1523 1524 /* Unset old boot EC */ 1525 if (boot_ec != ec) 1526 acpi_ec_free(boot_ec); 1527 1528 /* 1529 * ECDT device creation is split into acpi_ec_ecdt_probe() and 1530 * acpi_ec_ecdt_start(). This function takes care of completing the 1531 * ECDT parsing logic as the handle update should be performed 1532 * between the installation/uninstallation of the handlers. 1533 */ 1534 if (ec->handle != handle) 1535 ec->handle = handle; 1536 1537 ret = acpi_ec_setup(ec, handle_events); 1538 if (ret) 1539 return ret; 1540 1541 /* Set new boot EC */ 1542 if (!boot_ec) { 1543 boot_ec = ec; 1544 boot_ec_is_ecdt = is_ecdt; 1545 } 1546 1547 acpi_handle_info(boot_ec->handle, 1548 "Used as boot %s EC to handle transactions%s\n", 1549 is_ecdt ? "ECDT" : "DSDT", 1550 handle_events ? " and events" : ""); 1551 return ret; 1552 } 1553 1554 static bool acpi_ec_ecdt_get_handle(acpi_handle *phandle) 1555 { 1556 struct acpi_table_ecdt *ecdt_ptr; 1557 acpi_status status; 1558 acpi_handle handle; 1559 1560 status = acpi_get_table(ACPI_SIG_ECDT, 1, 1561 (struct acpi_table_header **)&ecdt_ptr); 1562 if (ACPI_FAILURE(status)) 1563 return false; 1564 1565 status = acpi_get_handle(NULL, ecdt_ptr->id, &handle); 1566 if (ACPI_FAILURE(status)) 1567 return false; 1568 1569 *phandle = handle; 1570 return true; 1571 } 1572 1573 static bool acpi_is_boot_ec(struct acpi_ec *ec) 1574 { 1575 if (!boot_ec) 1576 return false; 1577 if (ec->handle == boot_ec->handle && 1578 ec->gpe == boot_ec->gpe && 1579 ec->command_addr == boot_ec->command_addr && 1580 ec->data_addr == boot_ec->data_addr) 1581 return true; 1582 return false; 1583 } 1584 1585 static int acpi_ec_add(struct acpi_device *device) 1586 { 1587 struct acpi_ec *ec = NULL; 1588 int ret; 1589 1590 strcpy(acpi_device_name(device), ACPI_EC_DEVICE_NAME); 1591 strcpy(acpi_device_class(device), ACPI_EC_CLASS); 1592 1593 ec = acpi_ec_alloc(); 1594 if (!ec) 1595 return -ENOMEM; 1596 if (ec_parse_device(device->handle, 0, ec, NULL) != 1597 AE_CTRL_TERMINATE) { 1598 ret = -EINVAL; 1599 goto err_alloc; 1600 } 1601 1602 if (acpi_is_boot_ec(ec)) { 1603 boot_ec_is_ecdt = false; 1604 acpi_handle_debug(ec->handle, "duplicated.\n"); 1605 acpi_ec_free(ec); 1606 ec = boot_ec; 1607 ret = acpi_config_boot_ec(ec, ec->handle, true, false); 1608 } else 1609 ret = acpi_ec_setup(ec, true); 1610 if (ret) 1611 goto err_query; 1612 1613 device->driver_data = ec; 1614 1615 ret = !!request_region(ec->data_addr, 1, "EC data"); 1616 WARN(!ret, "Could not request EC data io port 0x%lx", ec->data_addr); 1617 ret = !!request_region(ec->command_addr, 1, "EC cmd"); 1618 WARN(!ret, "Could not request EC cmd io port 0x%lx", ec->command_addr); 1619 1620 /* Reprobe devices depending on the EC */ 1621 acpi_walk_dep_device_list(ec->handle); 1622 acpi_handle_debug(ec->handle, "enumerated.\n"); 1623 return 0; 1624 1625 err_query: 1626 if (ec != boot_ec) 1627 acpi_ec_remove_query_handlers(ec, true, 0); 1628 err_alloc: 1629 if (ec != boot_ec) 1630 acpi_ec_free(ec); 1631 return ret; 1632 } 1633 1634 static int acpi_ec_remove(struct acpi_device *device) 1635 { 1636 struct acpi_ec *ec; 1637 1638 if (!device) 1639 return -EINVAL; 1640 1641 ec = acpi_driver_data(device); 1642 release_region(ec->data_addr, 1); 1643 release_region(ec->command_addr, 1); 1644 device->driver_data = NULL; 1645 if (ec != boot_ec) { 1646 ec_remove_handlers(ec); 1647 acpi_ec_free(ec); 1648 } 1649 return 0; 1650 } 1651 1652 static acpi_status 1653 ec_parse_io_ports(struct acpi_resource *resource, void *context) 1654 { 1655 struct acpi_ec *ec = context; 1656 1657 if (resource->type != ACPI_RESOURCE_TYPE_IO) 1658 return AE_OK; 1659 1660 /* 1661 * The first address region returned is the data port, and 1662 * the second address region returned is the status/command 1663 * port. 1664 */ 1665 if (ec->data_addr == 0) 1666 ec->data_addr = resource->data.io.minimum; 1667 else if (ec->command_addr == 0) 1668 ec->command_addr = resource->data.io.minimum; 1669 else 1670 return AE_CTRL_TERMINATE; 1671 1672 return AE_OK; 1673 } 1674 1675 static const struct acpi_device_id ec_device_ids[] = { 1676 {"PNP0C09", 0}, 1677 {"", 0}, 1678 }; 1679 1680 /* 1681 * This function is not Windows-compatible as Windows never enumerates the 1682 * namespace EC before the main ACPI device enumeration process. It is 1683 * retained for historical reason and will be deprecated in the future. 1684 */ 1685 int __init acpi_ec_dsdt_probe(void) 1686 { 1687 acpi_status status; 1688 struct acpi_ec *ec; 1689 int ret; 1690 1691 /* 1692 * If a platform has ECDT, there is no need to proceed as the 1693 * following probe is not a part of the ACPI device enumeration, 1694 * executing _STA is not safe, and thus this probe may risk of 1695 * picking up an invalid EC device. 1696 */ 1697 if (boot_ec) 1698 return -ENODEV; 1699 1700 ec = acpi_ec_alloc(); 1701 if (!ec) 1702 return -ENOMEM; 1703 /* 1704 * At this point, the namespace is initialized, so start to find 1705 * the namespace objects. 1706 */ 1707 status = acpi_get_devices(ec_device_ids[0].id, 1708 ec_parse_device, ec, NULL); 1709 if (ACPI_FAILURE(status) || !ec->handle) { 1710 ret = -ENODEV; 1711 goto error; 1712 } 1713 /* 1714 * When the DSDT EC is available, always re-configure boot EC to 1715 * have _REG evaluated. _REG can only be evaluated after the 1716 * namespace initialization. 1717 * At this point, the GPE is not fully initialized, so do not to 1718 * handle the events. 1719 */ 1720 ret = acpi_config_boot_ec(ec, ec->handle, false, false); 1721 error: 1722 if (ret) 1723 acpi_ec_free(ec); 1724 return ret; 1725 } 1726 1727 /* 1728 * If the DSDT EC is not functioning, we still need to prepare a fully 1729 * functioning ECDT EC first in order to handle the events. 1730 * https://bugzilla.kernel.org/show_bug.cgi?id=115021 1731 */ 1732 int __init acpi_ec_ecdt_start(void) 1733 { 1734 acpi_handle handle; 1735 1736 if (!boot_ec) 1737 return -ENODEV; 1738 /* 1739 * The DSDT EC should have already been started in 1740 * acpi_ec_add(). 1741 */ 1742 if (!boot_ec_is_ecdt) 1743 return -ENODEV; 1744 1745 /* 1746 * At this point, the namespace and the GPE is initialized, so 1747 * start to find the namespace objects and handle the events. 1748 */ 1749 if (!acpi_ec_ecdt_get_handle(&handle)) 1750 return -ENODEV; 1751 return acpi_config_boot_ec(boot_ec, handle, true, true); 1752 } 1753 1754 #if 0 1755 /* 1756 * Some EC firmware variations refuses to respond QR_EC when SCI_EVT is not 1757 * set, for which case, we complete the QR_EC without issuing it to the 1758 * firmware. 1759 * https://bugzilla.kernel.org/show_bug.cgi?id=82611 1760 * https://bugzilla.kernel.org/show_bug.cgi?id=97381 1761 */ 1762 static int ec_flag_query_handshake(const struct dmi_system_id *id) 1763 { 1764 pr_debug("Detected the EC firmware requiring QR_EC issued when SCI_EVT set\n"); 1765 EC_FLAGS_QUERY_HANDSHAKE = 1; 1766 return 0; 1767 } 1768 #endif 1769 1770 /* 1771 * Some ECDTs contain wrong register addresses. 1772 * MSI MS-171F 1773 * https://bugzilla.kernel.org/show_bug.cgi?id=12461 1774 */ 1775 static int ec_correct_ecdt(const struct dmi_system_id *id) 1776 { 1777 pr_debug("Detected system needing ECDT address correction.\n"); 1778 EC_FLAGS_CORRECT_ECDT = 1; 1779 return 0; 1780 } 1781 1782 /* 1783 * Some DSDTs contain wrong GPE setting. 1784 * Asus FX502VD/VE, GL702VMK, X550VXK, X580VD 1785 * https://bugzilla.kernel.org/show_bug.cgi?id=195651 1786 */ 1787 static int ec_honor_ecdt_gpe(const struct dmi_system_id *id) 1788 { 1789 pr_debug("Detected system needing ignore DSDT GPE setting.\n"); 1790 EC_FLAGS_IGNORE_DSDT_GPE = 1; 1791 return 0; 1792 } 1793 1794 static struct dmi_system_id ec_dmi_table[] __initdata = { 1795 { 1796 ec_correct_ecdt, "MSI MS-171F", { 1797 DMI_MATCH(DMI_SYS_VENDOR, "Micro-Star"), 1798 DMI_MATCH(DMI_PRODUCT_NAME, "MS-171F"),}, NULL}, 1799 { 1800 ec_honor_ecdt_gpe, "ASUS FX502VD", { 1801 DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK COMPUTER INC."), 1802 DMI_MATCH(DMI_PRODUCT_NAME, "FX502VD"),}, NULL}, 1803 { 1804 ec_honor_ecdt_gpe, "ASUS FX502VE", { 1805 DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK COMPUTER INC."), 1806 DMI_MATCH(DMI_PRODUCT_NAME, "FX502VE"),}, NULL}, 1807 { 1808 ec_honor_ecdt_gpe, "ASUS GL702VMK", { 1809 DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK COMPUTER INC."), 1810 DMI_MATCH(DMI_PRODUCT_NAME, "GL702VMK"),}, NULL}, 1811 { 1812 ec_honor_ecdt_gpe, "ASUS X550VXK", { 1813 DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK COMPUTER INC."), 1814 DMI_MATCH(DMI_PRODUCT_NAME, "X550VXK"),}, NULL}, 1815 { 1816 ec_honor_ecdt_gpe, "ASUS X580VD", { 1817 DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK COMPUTER INC."), 1818 DMI_MATCH(DMI_PRODUCT_NAME, "X580VD"),}, NULL}, 1819 {}, 1820 }; 1821 1822 int __init acpi_ec_ecdt_probe(void) 1823 { 1824 int ret; 1825 acpi_status status; 1826 struct acpi_table_ecdt *ecdt_ptr; 1827 struct acpi_ec *ec; 1828 1829 ec = acpi_ec_alloc(); 1830 if (!ec) 1831 return -ENOMEM; 1832 /* 1833 * Generate a boot ec context 1834 */ 1835 dmi_check_system(ec_dmi_table); 1836 status = acpi_get_table(ACPI_SIG_ECDT, 1, 1837 (struct acpi_table_header **)&ecdt_ptr); 1838 if (ACPI_FAILURE(status)) { 1839 ret = -ENODEV; 1840 goto error; 1841 } 1842 1843 if (!ecdt_ptr->control.address || !ecdt_ptr->data.address) { 1844 /* 1845 * Asus X50GL: 1846 * https://bugzilla.kernel.org/show_bug.cgi?id=11880 1847 */ 1848 ret = -ENODEV; 1849 goto error; 1850 } 1851 1852 if (EC_FLAGS_CORRECT_ECDT) { 1853 ec->command_addr = ecdt_ptr->data.address; 1854 ec->data_addr = ecdt_ptr->control.address; 1855 } else { 1856 ec->command_addr = ecdt_ptr->control.address; 1857 ec->data_addr = ecdt_ptr->data.address; 1858 } 1859 ec->gpe = ecdt_ptr->gpe; 1860 1861 /* 1862 * At this point, the namespace is not initialized, so do not find 1863 * the namespace objects, or handle the events. 1864 */ 1865 ret = acpi_config_boot_ec(ec, ACPI_ROOT_OBJECT, false, true); 1866 error: 1867 if (ret) 1868 acpi_ec_free(ec); 1869 return ret; 1870 } 1871 1872 #ifdef CONFIG_PM_SLEEP 1873 static int acpi_ec_suspend(struct device *dev) 1874 { 1875 struct acpi_ec *ec = 1876 acpi_driver_data(to_acpi_device(dev)); 1877 1878 if (acpi_sleep_no_ec_events() && ec_freeze_events) 1879 acpi_ec_disable_event(ec); 1880 return 0; 1881 } 1882 1883 static int acpi_ec_resume(struct device *dev) 1884 { 1885 struct acpi_ec *ec = 1886 acpi_driver_data(to_acpi_device(dev)); 1887 1888 acpi_ec_enable_event(ec); 1889 return 0; 1890 } 1891 #endif 1892 1893 static const struct dev_pm_ops acpi_ec_pm = { 1894 SET_SYSTEM_SLEEP_PM_OPS(acpi_ec_suspend, acpi_ec_resume) 1895 }; 1896 1897 static int param_set_event_clearing(const char *val, struct kernel_param *kp) 1898 { 1899 int result = 0; 1900 1901 if (!strncmp(val, "status", sizeof("status") - 1)) { 1902 ec_event_clearing = ACPI_EC_EVT_TIMING_STATUS; 1903 pr_info("Assuming SCI_EVT clearing on EC_SC accesses\n"); 1904 } else if (!strncmp(val, "query", sizeof("query") - 1)) { 1905 ec_event_clearing = ACPI_EC_EVT_TIMING_QUERY; 1906 pr_info("Assuming SCI_EVT clearing on QR_EC writes\n"); 1907 } else if (!strncmp(val, "event", sizeof("event") - 1)) { 1908 ec_event_clearing = ACPI_EC_EVT_TIMING_EVENT; 1909 pr_info("Assuming SCI_EVT clearing on event reads\n"); 1910 } else 1911 result = -EINVAL; 1912 return result; 1913 } 1914 1915 static int param_get_event_clearing(char *buffer, struct kernel_param *kp) 1916 { 1917 switch (ec_event_clearing) { 1918 case ACPI_EC_EVT_TIMING_STATUS: 1919 return sprintf(buffer, "status"); 1920 case ACPI_EC_EVT_TIMING_QUERY: 1921 return sprintf(buffer, "query"); 1922 case ACPI_EC_EVT_TIMING_EVENT: 1923 return sprintf(buffer, "event"); 1924 default: 1925 return sprintf(buffer, "invalid"); 1926 } 1927 return 0; 1928 } 1929 1930 module_param_call(ec_event_clearing, param_set_event_clearing, param_get_event_clearing, 1931 NULL, 0644); 1932 MODULE_PARM_DESC(ec_event_clearing, "Assumed SCI_EVT clearing timing"); 1933 1934 static struct acpi_driver acpi_ec_driver = { 1935 .name = "ec", 1936 .class = ACPI_EC_CLASS, 1937 .ids = ec_device_ids, 1938 .ops = { 1939 .add = acpi_ec_add, 1940 .remove = acpi_ec_remove, 1941 }, 1942 .drv.pm = &acpi_ec_pm, 1943 }; 1944 1945 static inline int acpi_ec_query_init(void) 1946 { 1947 if (!ec_query_wq) { 1948 ec_query_wq = alloc_workqueue("kec_query", 0, 1949 ec_max_queries); 1950 if (!ec_query_wq) 1951 return -ENODEV; 1952 } 1953 return 0; 1954 } 1955 1956 static inline void acpi_ec_query_exit(void) 1957 { 1958 if (ec_query_wq) { 1959 destroy_workqueue(ec_query_wq); 1960 ec_query_wq = NULL; 1961 } 1962 } 1963 1964 int __init acpi_ec_init(void) 1965 { 1966 int result; 1967 1968 /* register workqueue for _Qxx evaluations */ 1969 result = acpi_ec_query_init(); 1970 if (result) 1971 goto err_exit; 1972 /* Now register the driver for the EC */ 1973 result = acpi_bus_register_driver(&acpi_ec_driver); 1974 if (result) 1975 goto err_exit; 1976 1977 err_exit: 1978 if (result) 1979 acpi_ec_query_exit(); 1980 return result; 1981 } 1982 1983 /* EC driver currently not unloadable */ 1984 #if 0 1985 static void __exit acpi_ec_exit(void) 1986 { 1987 1988 acpi_bus_unregister_driver(&acpi_ec_driver); 1989 acpi_ec_query_exit(); 1990 } 1991 #endif /* 0 */ 1992