1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * ec.c - ACPI Embedded Controller Driver (v3) 4 * 5 * Copyright (C) 2001-2015 Intel Corporation 6 * Author: 2014, 2015 Lv Zheng <lv.zheng@intel.com> 7 * 2006, 2007 Alexey Starikovskiy <alexey.y.starikovskiy@intel.com> 8 * 2006 Denis Sadykov <denis.m.sadykov@intel.com> 9 * 2004 Luming Yu <luming.yu@intel.com> 10 * 2001, 2002 Andy Grover <andrew.grover@intel.com> 11 * 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com> 12 * Copyright (C) 2008 Alexey Starikovskiy <astarikovskiy@suse.de> 13 */ 14 15 /* Uncomment next line to get verbose printout */ 16 /* #define DEBUG */ 17 #define pr_fmt(fmt) "ACPI: EC: " fmt 18 19 #include <linux/kernel.h> 20 #include <linux/module.h> 21 #include <linux/init.h> 22 #include <linux/types.h> 23 #include <linux/delay.h> 24 #include <linux/interrupt.h> 25 #include <linux/list.h> 26 #include <linux/spinlock.h> 27 #include <linux/slab.h> 28 #include <linux/suspend.h> 29 #include <linux/acpi.h> 30 #include <linux/dmi.h> 31 #include <asm/io.h> 32 33 #include "internal.h" 34 35 #define ACPI_EC_CLASS "embedded_controller" 36 #define ACPI_EC_DEVICE_NAME "Embedded Controller" 37 38 /* EC status register */ 39 #define ACPI_EC_FLAG_OBF 0x01 /* Output buffer full */ 40 #define ACPI_EC_FLAG_IBF 0x02 /* Input buffer full */ 41 #define ACPI_EC_FLAG_CMD 0x08 /* Input buffer contains a command */ 42 #define ACPI_EC_FLAG_BURST 0x10 /* burst mode */ 43 #define ACPI_EC_FLAG_SCI 0x20 /* EC-SCI occurred */ 44 45 /* 46 * The SCI_EVT clearing timing is not defined by the ACPI specification. 47 * This leads to lots of practical timing issues for the host EC driver. 48 * The following variations are defined (from the target EC firmware's 49 * perspective): 50 * STATUS: After indicating SCI_EVT edge triggered IRQ to the host, the 51 * target can clear SCI_EVT at any time so long as the host can see 52 * the indication by reading the status register (EC_SC). So the 53 * host should re-check SCI_EVT after the first time the SCI_EVT 54 * indication is seen, which is the same time the query request 55 * (QR_EC) is written to the command register (EC_CMD). SCI_EVT set 56 * at any later time could indicate another event. Normally such 57 * kind of EC firmware has implemented an event queue and will 58 * return 0x00 to indicate "no outstanding event". 59 * QUERY: After seeing the query request (QR_EC) written to the command 60 * register (EC_CMD) by the host and having prepared the responding 61 * event value in the data register (EC_DATA), the target can safely 62 * clear SCI_EVT because the target can confirm that the current 63 * event is being handled by the host. The host then should check 64 * SCI_EVT right after reading the event response from the data 65 * register (EC_DATA). 66 * EVENT: After seeing the event response read from the data register 67 * (EC_DATA) by the host, the target can clear SCI_EVT. As the 68 * target requires time to notice the change in the data register 69 * (EC_DATA), the host may be required to wait additional guarding 70 * time before checking the SCI_EVT again. Such guarding may not be 71 * necessary if the host is notified via another IRQ. 72 */ 73 #define ACPI_EC_EVT_TIMING_STATUS 0x00 74 #define ACPI_EC_EVT_TIMING_QUERY 0x01 75 #define ACPI_EC_EVT_TIMING_EVENT 0x02 76 77 /* EC commands */ 78 enum ec_command { 79 ACPI_EC_COMMAND_READ = 0x80, 80 ACPI_EC_COMMAND_WRITE = 0x81, 81 ACPI_EC_BURST_ENABLE = 0x82, 82 ACPI_EC_BURST_DISABLE = 0x83, 83 ACPI_EC_COMMAND_QUERY = 0x84, 84 }; 85 86 #define ACPI_EC_DELAY 500 /* Wait 500ms max. during EC ops */ 87 #define ACPI_EC_UDELAY_GLK 1000 /* Wait 1ms max. to get global lock */ 88 #define ACPI_EC_UDELAY_POLL 550 /* Wait 1ms for EC transaction polling */ 89 #define ACPI_EC_CLEAR_MAX 100 /* Maximum number of events to query 90 * when trying to clear the EC */ 91 #define ACPI_EC_MAX_QUERIES 16 /* Maximum number of parallel queries */ 92 93 enum { 94 EC_FLAGS_QUERY_ENABLED, /* Query is enabled */ 95 EC_FLAGS_EVENT_HANDLER_INSTALLED, /* Event handler installed */ 96 EC_FLAGS_EC_HANDLER_INSTALLED, /* OpReg handler installed */ 97 EC_FLAGS_EC_REG_CALLED, /* OpReg ACPI _REG method called */ 98 EC_FLAGS_QUERY_METHODS_INSTALLED, /* _Qxx handlers installed */ 99 EC_FLAGS_STARTED, /* Driver is started */ 100 EC_FLAGS_STOPPED, /* Driver is stopped */ 101 EC_FLAGS_EVENTS_MASKED, /* Events masked */ 102 }; 103 104 #define ACPI_EC_COMMAND_POLL 0x01 /* Available for command byte */ 105 #define ACPI_EC_COMMAND_COMPLETE 0x02 /* Completed last byte */ 106 107 /* ec.c is compiled in acpi namespace so this shows up as acpi.ec_delay param */ 108 static unsigned int ec_delay __read_mostly = ACPI_EC_DELAY; 109 module_param(ec_delay, uint, 0644); 110 MODULE_PARM_DESC(ec_delay, "Timeout(ms) waited until an EC command completes"); 111 112 static unsigned int ec_max_queries __read_mostly = ACPI_EC_MAX_QUERIES; 113 module_param(ec_max_queries, uint, 0644); 114 MODULE_PARM_DESC(ec_max_queries, "Maximum parallel _Qxx evaluations"); 115 116 static bool ec_busy_polling __read_mostly; 117 module_param(ec_busy_polling, bool, 0644); 118 MODULE_PARM_DESC(ec_busy_polling, "Use busy polling to advance EC transaction"); 119 120 static unsigned int ec_polling_guard __read_mostly = ACPI_EC_UDELAY_POLL; 121 module_param(ec_polling_guard, uint, 0644); 122 MODULE_PARM_DESC(ec_polling_guard, "Guard time(us) between EC accesses in polling modes"); 123 124 static unsigned int ec_event_clearing __read_mostly = ACPI_EC_EVT_TIMING_QUERY; 125 126 /* 127 * If the number of false interrupts per one transaction exceeds 128 * this threshold, will think there is a GPE storm happened and 129 * will disable the GPE for normal transaction. 130 */ 131 static unsigned int ec_storm_threshold __read_mostly = 8; 132 module_param(ec_storm_threshold, uint, 0644); 133 MODULE_PARM_DESC(ec_storm_threshold, "Maxim false GPE numbers not considered as GPE storm"); 134 135 static bool ec_freeze_events __read_mostly; 136 module_param(ec_freeze_events, bool, 0644); 137 MODULE_PARM_DESC(ec_freeze_events, "Disabling event handling during suspend/resume"); 138 139 static bool ec_no_wakeup __read_mostly; 140 module_param(ec_no_wakeup, bool, 0644); 141 MODULE_PARM_DESC(ec_no_wakeup, "Do not wake up from suspend-to-idle"); 142 143 struct acpi_ec_query_handler { 144 struct list_head node; 145 acpi_ec_query_func func; 146 acpi_handle handle; 147 void *data; 148 u8 query_bit; 149 struct kref kref; 150 }; 151 152 struct transaction { 153 const u8 *wdata; 154 u8 *rdata; 155 unsigned short irq_count; 156 u8 command; 157 u8 wi; 158 u8 ri; 159 u8 wlen; 160 u8 rlen; 161 u8 flags; 162 }; 163 164 struct acpi_ec_query { 165 struct transaction transaction; 166 struct work_struct work; 167 struct acpi_ec_query_handler *handler; 168 struct acpi_ec *ec; 169 }; 170 171 static int acpi_ec_submit_query(struct acpi_ec *ec); 172 static void advance_transaction(struct acpi_ec *ec, bool interrupt); 173 static void acpi_ec_event_handler(struct work_struct *work); 174 175 struct acpi_ec *first_ec; 176 EXPORT_SYMBOL(first_ec); 177 178 static struct acpi_ec *boot_ec; 179 static bool boot_ec_is_ecdt; 180 static struct workqueue_struct *ec_wq; 181 static struct workqueue_struct *ec_query_wq; 182 183 static int EC_FLAGS_CORRECT_ECDT; /* Needs ECDT port address correction */ 184 static int EC_FLAGS_TRUST_DSDT_GPE; /* Needs DSDT GPE as correction setting */ 185 static int EC_FLAGS_CLEAR_ON_RESUME; /* Needs acpi_ec_clear() on boot/resume */ 186 187 /* -------------------------------------------------------------------------- 188 * Logging/Debugging 189 * -------------------------------------------------------------------------- */ 190 191 /* 192 * Splitters used by the developers to track the boundary of the EC 193 * handling processes. 194 */ 195 #ifdef DEBUG 196 #define EC_DBG_SEP " " 197 #define EC_DBG_DRV "+++++" 198 #define EC_DBG_STM "=====" 199 #define EC_DBG_REQ "*****" 200 #define EC_DBG_EVT "#####" 201 #else 202 #define EC_DBG_SEP "" 203 #define EC_DBG_DRV 204 #define EC_DBG_STM 205 #define EC_DBG_REQ 206 #define EC_DBG_EVT 207 #endif 208 209 #define ec_log_raw(fmt, ...) \ 210 pr_info(fmt "\n", ##__VA_ARGS__) 211 #define ec_dbg_raw(fmt, ...) \ 212 pr_debug(fmt "\n", ##__VA_ARGS__) 213 #define ec_log(filter, fmt, ...) \ 214 ec_log_raw(filter EC_DBG_SEP fmt EC_DBG_SEP filter, ##__VA_ARGS__) 215 #define ec_dbg(filter, fmt, ...) \ 216 ec_dbg_raw(filter EC_DBG_SEP fmt EC_DBG_SEP filter, ##__VA_ARGS__) 217 218 #define ec_log_drv(fmt, ...) \ 219 ec_log(EC_DBG_DRV, fmt, ##__VA_ARGS__) 220 #define ec_dbg_drv(fmt, ...) \ 221 ec_dbg(EC_DBG_DRV, fmt, ##__VA_ARGS__) 222 #define ec_dbg_stm(fmt, ...) \ 223 ec_dbg(EC_DBG_STM, fmt, ##__VA_ARGS__) 224 #define ec_dbg_req(fmt, ...) \ 225 ec_dbg(EC_DBG_REQ, fmt, ##__VA_ARGS__) 226 #define ec_dbg_evt(fmt, ...) \ 227 ec_dbg(EC_DBG_EVT, fmt, ##__VA_ARGS__) 228 #define ec_dbg_ref(ec, fmt, ...) \ 229 ec_dbg_raw("%lu: " fmt, ec->reference_count, ## __VA_ARGS__) 230 231 /* -------------------------------------------------------------------------- 232 * Device Flags 233 * -------------------------------------------------------------------------- */ 234 235 static bool acpi_ec_started(struct acpi_ec *ec) 236 { 237 return test_bit(EC_FLAGS_STARTED, &ec->flags) && 238 !test_bit(EC_FLAGS_STOPPED, &ec->flags); 239 } 240 241 static bool acpi_ec_event_enabled(struct acpi_ec *ec) 242 { 243 /* 244 * There is an OSPM early stage logic. During the early stages 245 * (boot/resume), OSPMs shouldn't enable the event handling, only 246 * the EC transactions are allowed to be performed. 247 */ 248 if (!test_bit(EC_FLAGS_QUERY_ENABLED, &ec->flags)) 249 return false; 250 /* 251 * However, disabling the event handling is experimental for late 252 * stage (suspend), and is controlled by the boot parameter of 253 * "ec_freeze_events": 254 * 1. true: The EC event handling is disabled before entering 255 * the noirq stage. 256 * 2. false: The EC event handling is automatically disabled as 257 * soon as the EC driver is stopped. 258 */ 259 if (ec_freeze_events) 260 return acpi_ec_started(ec); 261 else 262 return test_bit(EC_FLAGS_STARTED, &ec->flags); 263 } 264 265 static bool acpi_ec_flushed(struct acpi_ec *ec) 266 { 267 return ec->reference_count == 1; 268 } 269 270 /* -------------------------------------------------------------------------- 271 * EC Registers 272 * -------------------------------------------------------------------------- */ 273 274 static inline u8 acpi_ec_read_status(struct acpi_ec *ec) 275 { 276 u8 x = inb(ec->command_addr); 277 278 ec_dbg_raw("EC_SC(R) = 0x%2.2x " 279 "SCI_EVT=%d BURST=%d CMD=%d IBF=%d OBF=%d", 280 x, 281 !!(x & ACPI_EC_FLAG_SCI), 282 !!(x & ACPI_EC_FLAG_BURST), 283 !!(x & ACPI_EC_FLAG_CMD), 284 !!(x & ACPI_EC_FLAG_IBF), 285 !!(x & ACPI_EC_FLAG_OBF)); 286 return x; 287 } 288 289 static inline u8 acpi_ec_read_data(struct acpi_ec *ec) 290 { 291 u8 x = inb(ec->data_addr); 292 293 ec->timestamp = jiffies; 294 ec_dbg_raw("EC_DATA(R) = 0x%2.2x", x); 295 return x; 296 } 297 298 static inline void acpi_ec_write_cmd(struct acpi_ec *ec, u8 command) 299 { 300 ec_dbg_raw("EC_SC(W) = 0x%2.2x", command); 301 outb(command, ec->command_addr); 302 ec->timestamp = jiffies; 303 } 304 305 static inline void acpi_ec_write_data(struct acpi_ec *ec, u8 data) 306 { 307 ec_dbg_raw("EC_DATA(W) = 0x%2.2x", data); 308 outb(data, ec->data_addr); 309 ec->timestamp = jiffies; 310 } 311 312 #if defined(DEBUG) || defined(CONFIG_DYNAMIC_DEBUG) 313 static const char *acpi_ec_cmd_string(u8 cmd) 314 { 315 switch (cmd) { 316 case 0x80: 317 return "RD_EC"; 318 case 0x81: 319 return "WR_EC"; 320 case 0x82: 321 return "BE_EC"; 322 case 0x83: 323 return "BD_EC"; 324 case 0x84: 325 return "QR_EC"; 326 } 327 return "UNKNOWN"; 328 } 329 #else 330 #define acpi_ec_cmd_string(cmd) "UNDEF" 331 #endif 332 333 /* -------------------------------------------------------------------------- 334 * GPE Registers 335 * -------------------------------------------------------------------------- */ 336 337 static inline bool acpi_ec_gpe_status_set(struct acpi_ec *ec) 338 { 339 acpi_event_status gpe_status = 0; 340 341 (void)acpi_get_gpe_status(NULL, ec->gpe, &gpe_status); 342 return !!(gpe_status & ACPI_EVENT_FLAG_STATUS_SET); 343 } 344 345 static inline void acpi_ec_enable_gpe(struct acpi_ec *ec, bool open) 346 { 347 if (open) 348 acpi_enable_gpe(NULL, ec->gpe); 349 else { 350 BUG_ON(ec->reference_count < 1); 351 acpi_set_gpe(NULL, ec->gpe, ACPI_GPE_ENABLE); 352 } 353 if (acpi_ec_gpe_status_set(ec)) { 354 /* 355 * On some platforms, EN=1 writes cannot trigger GPE. So 356 * software need to manually trigger a pseudo GPE event on 357 * EN=1 writes. 358 */ 359 ec_dbg_raw("Polling quirk"); 360 advance_transaction(ec, false); 361 } 362 } 363 364 static inline void acpi_ec_disable_gpe(struct acpi_ec *ec, bool close) 365 { 366 if (close) 367 acpi_disable_gpe(NULL, ec->gpe); 368 else { 369 BUG_ON(ec->reference_count < 1); 370 acpi_set_gpe(NULL, ec->gpe, ACPI_GPE_DISABLE); 371 } 372 } 373 374 /* -------------------------------------------------------------------------- 375 * Transaction Management 376 * -------------------------------------------------------------------------- */ 377 378 static void acpi_ec_submit_request(struct acpi_ec *ec) 379 { 380 ec->reference_count++; 381 if (test_bit(EC_FLAGS_EVENT_HANDLER_INSTALLED, &ec->flags) && 382 ec->gpe >= 0 && ec->reference_count == 1) 383 acpi_ec_enable_gpe(ec, true); 384 } 385 386 static void acpi_ec_complete_request(struct acpi_ec *ec) 387 { 388 bool flushed = false; 389 390 ec->reference_count--; 391 if (test_bit(EC_FLAGS_EVENT_HANDLER_INSTALLED, &ec->flags) && 392 ec->gpe >= 0 && ec->reference_count == 0) 393 acpi_ec_disable_gpe(ec, true); 394 flushed = acpi_ec_flushed(ec); 395 if (flushed) 396 wake_up(&ec->wait); 397 } 398 399 static void acpi_ec_mask_events(struct acpi_ec *ec) 400 { 401 if (!test_bit(EC_FLAGS_EVENTS_MASKED, &ec->flags)) { 402 if (ec->gpe >= 0) 403 acpi_ec_disable_gpe(ec, false); 404 else 405 disable_irq_nosync(ec->irq); 406 407 ec_dbg_drv("Polling enabled"); 408 set_bit(EC_FLAGS_EVENTS_MASKED, &ec->flags); 409 } 410 } 411 412 static void acpi_ec_unmask_events(struct acpi_ec *ec) 413 { 414 if (test_bit(EC_FLAGS_EVENTS_MASKED, &ec->flags)) { 415 clear_bit(EC_FLAGS_EVENTS_MASKED, &ec->flags); 416 if (ec->gpe >= 0) 417 acpi_ec_enable_gpe(ec, false); 418 else 419 enable_irq(ec->irq); 420 421 ec_dbg_drv("Polling disabled"); 422 } 423 } 424 425 /* 426 * acpi_ec_submit_flushable_request() - Increase the reference count unless 427 * the flush operation is not in 428 * progress 429 * @ec: the EC device 430 * 431 * This function must be used before taking a new action that should hold 432 * the reference count. If this function returns false, then the action 433 * must be discarded or it will prevent the flush operation from being 434 * completed. 435 */ 436 static bool acpi_ec_submit_flushable_request(struct acpi_ec *ec) 437 { 438 if (!acpi_ec_started(ec)) 439 return false; 440 acpi_ec_submit_request(ec); 441 return true; 442 } 443 444 static void acpi_ec_submit_event(struct acpi_ec *ec) 445 { 446 /* 447 * It is safe to mask the events here, because acpi_ec_close_event() 448 * will run at least once after this. 449 */ 450 acpi_ec_mask_events(ec); 451 if (!acpi_ec_event_enabled(ec)) 452 return; 453 454 if (ec->event_state != EC_EVENT_READY) 455 return; 456 457 ec_dbg_evt("Command(%s) submitted/blocked", 458 acpi_ec_cmd_string(ACPI_EC_COMMAND_QUERY)); 459 460 ec->event_state = EC_EVENT_IN_PROGRESS; 461 /* 462 * If events_to_process is greater than 0 at this point, the while () 463 * loop in acpi_ec_event_handler() is still running and incrementing 464 * events_to_process will cause it to invoke acpi_ec_submit_query() once 465 * more, so it is not necessary to queue up the event work to start the 466 * same loop again. 467 */ 468 if (ec->events_to_process++ > 0) 469 return; 470 471 ec->events_in_progress++; 472 queue_work(ec_wq, &ec->work); 473 } 474 475 static void acpi_ec_complete_event(struct acpi_ec *ec) 476 { 477 if (ec->event_state == EC_EVENT_IN_PROGRESS) 478 ec->event_state = EC_EVENT_COMPLETE; 479 } 480 481 static void acpi_ec_close_event(struct acpi_ec *ec) 482 { 483 if (ec->event_state != EC_EVENT_READY) 484 ec_dbg_evt("Command(%s) unblocked", 485 acpi_ec_cmd_string(ACPI_EC_COMMAND_QUERY)); 486 487 ec->event_state = EC_EVENT_READY; 488 acpi_ec_unmask_events(ec); 489 } 490 491 static inline void __acpi_ec_enable_event(struct acpi_ec *ec) 492 { 493 if (!test_and_set_bit(EC_FLAGS_QUERY_ENABLED, &ec->flags)) 494 ec_log_drv("event unblocked"); 495 /* 496 * Unconditionally invoke this once after enabling the event 497 * handling mechanism to detect the pending events. 498 */ 499 advance_transaction(ec, false); 500 } 501 502 static inline void __acpi_ec_disable_event(struct acpi_ec *ec) 503 { 504 if (test_and_clear_bit(EC_FLAGS_QUERY_ENABLED, &ec->flags)) 505 ec_log_drv("event blocked"); 506 } 507 508 /* 509 * Process _Q events that might have accumulated in the EC. 510 * Run with locked ec mutex. 511 */ 512 static void acpi_ec_clear(struct acpi_ec *ec) 513 { 514 int i; 515 516 for (i = 0; i < ACPI_EC_CLEAR_MAX; i++) { 517 if (acpi_ec_submit_query(ec)) 518 break; 519 } 520 if (unlikely(i == ACPI_EC_CLEAR_MAX)) 521 pr_warn("Warning: Maximum of %d stale EC events cleared\n", i); 522 else 523 pr_info("%d stale EC events cleared\n", i); 524 } 525 526 static void acpi_ec_enable_event(struct acpi_ec *ec) 527 { 528 unsigned long flags; 529 530 spin_lock_irqsave(&ec->lock, flags); 531 if (acpi_ec_started(ec)) 532 __acpi_ec_enable_event(ec); 533 spin_unlock_irqrestore(&ec->lock, flags); 534 535 /* Drain additional events if hardware requires that */ 536 if (EC_FLAGS_CLEAR_ON_RESUME) 537 acpi_ec_clear(ec); 538 } 539 540 #ifdef CONFIG_PM_SLEEP 541 static void __acpi_ec_flush_work(void) 542 { 543 flush_workqueue(ec_wq); /* flush ec->work */ 544 flush_workqueue(ec_query_wq); /* flush queries */ 545 } 546 547 static void acpi_ec_disable_event(struct acpi_ec *ec) 548 { 549 unsigned long flags; 550 551 spin_lock_irqsave(&ec->lock, flags); 552 __acpi_ec_disable_event(ec); 553 spin_unlock_irqrestore(&ec->lock, flags); 554 555 /* 556 * When ec_freeze_events is true, we need to flush events in 557 * the proper position before entering the noirq stage. 558 */ 559 __acpi_ec_flush_work(); 560 } 561 562 void acpi_ec_flush_work(void) 563 { 564 /* Without ec_wq there is nothing to flush. */ 565 if (!ec_wq) 566 return; 567 568 __acpi_ec_flush_work(); 569 } 570 #endif /* CONFIG_PM_SLEEP */ 571 572 static bool acpi_ec_guard_event(struct acpi_ec *ec) 573 { 574 unsigned long flags; 575 bool guarded; 576 577 spin_lock_irqsave(&ec->lock, flags); 578 /* 579 * If firmware SCI_EVT clearing timing is "event", we actually 580 * don't know when the SCI_EVT will be cleared by firmware after 581 * evaluating _Qxx, so we need to re-check SCI_EVT after waiting an 582 * acceptable period. 583 * 584 * The guarding period is applicable if the event state is not 585 * EC_EVENT_READY, but otherwise if the current transaction is of the 586 * ACPI_EC_COMMAND_QUERY type, the guarding should have elapsed already 587 * and it should not be applied to let the transaction transition into 588 * the ACPI_EC_COMMAND_POLL state immediately. 589 */ 590 guarded = ec_event_clearing == ACPI_EC_EVT_TIMING_EVENT && 591 ec->event_state != EC_EVENT_READY && 592 (!ec->curr || ec->curr->command != ACPI_EC_COMMAND_QUERY); 593 spin_unlock_irqrestore(&ec->lock, flags); 594 return guarded; 595 } 596 597 static int ec_transaction_polled(struct acpi_ec *ec) 598 { 599 unsigned long flags; 600 int ret = 0; 601 602 spin_lock_irqsave(&ec->lock, flags); 603 if (ec->curr && (ec->curr->flags & ACPI_EC_COMMAND_POLL)) 604 ret = 1; 605 spin_unlock_irqrestore(&ec->lock, flags); 606 return ret; 607 } 608 609 static int ec_transaction_completed(struct acpi_ec *ec) 610 { 611 unsigned long flags; 612 int ret = 0; 613 614 spin_lock_irqsave(&ec->lock, flags); 615 if (ec->curr && (ec->curr->flags & ACPI_EC_COMMAND_COMPLETE)) 616 ret = 1; 617 spin_unlock_irqrestore(&ec->lock, flags); 618 return ret; 619 } 620 621 static inline void ec_transaction_transition(struct acpi_ec *ec, unsigned long flag) 622 { 623 ec->curr->flags |= flag; 624 625 if (ec->curr->command != ACPI_EC_COMMAND_QUERY) 626 return; 627 628 switch (ec_event_clearing) { 629 case ACPI_EC_EVT_TIMING_STATUS: 630 if (flag == ACPI_EC_COMMAND_POLL) 631 acpi_ec_close_event(ec); 632 633 return; 634 635 case ACPI_EC_EVT_TIMING_QUERY: 636 if (flag == ACPI_EC_COMMAND_COMPLETE) 637 acpi_ec_close_event(ec); 638 639 return; 640 641 case ACPI_EC_EVT_TIMING_EVENT: 642 if (flag == ACPI_EC_COMMAND_COMPLETE) 643 acpi_ec_complete_event(ec); 644 } 645 } 646 647 static void acpi_ec_spurious_interrupt(struct acpi_ec *ec, struct transaction *t) 648 { 649 if (t->irq_count < ec_storm_threshold) 650 ++t->irq_count; 651 652 /* Trigger if the threshold is 0 too. */ 653 if (t->irq_count == ec_storm_threshold) 654 acpi_ec_mask_events(ec); 655 } 656 657 static void advance_transaction(struct acpi_ec *ec, bool interrupt) 658 { 659 struct transaction *t = ec->curr; 660 bool wakeup = false; 661 u8 status; 662 663 ec_dbg_stm("%s (%d)", interrupt ? "IRQ" : "TASK", smp_processor_id()); 664 665 /* 666 * Clear GPE_STS upfront to allow subsequent hardware GPE_STS 0->1 667 * changes to always trigger a GPE interrupt. 668 * 669 * GPE STS is a W1C register, which means: 670 * 671 * 1. Software can clear it without worrying about clearing the other 672 * GPEs' STS bits when the hardware sets them in parallel. 673 * 674 * 2. As long as software can ensure only clearing it when it is set, 675 * hardware won't set it in parallel. 676 */ 677 if (ec->gpe >= 0 && acpi_ec_gpe_status_set(ec)) 678 acpi_clear_gpe(NULL, ec->gpe); 679 680 status = acpi_ec_read_status(ec); 681 682 /* 683 * Another IRQ or a guarded polling mode advancement is detected, 684 * the next QR_EC submission is then allowed. 685 */ 686 if (!t || !(t->flags & ACPI_EC_COMMAND_POLL)) { 687 if (ec_event_clearing == ACPI_EC_EVT_TIMING_EVENT && 688 ec->event_state == EC_EVENT_COMPLETE) 689 acpi_ec_close_event(ec); 690 691 if (!t) 692 goto out; 693 } 694 695 if (t->flags & ACPI_EC_COMMAND_POLL) { 696 if (t->wlen > t->wi) { 697 if (!(status & ACPI_EC_FLAG_IBF)) 698 acpi_ec_write_data(ec, t->wdata[t->wi++]); 699 else if (interrupt && !(status & ACPI_EC_FLAG_SCI)) 700 acpi_ec_spurious_interrupt(ec, t); 701 } else if (t->rlen > t->ri) { 702 if (status & ACPI_EC_FLAG_OBF) { 703 t->rdata[t->ri++] = acpi_ec_read_data(ec); 704 if (t->rlen == t->ri) { 705 ec_transaction_transition(ec, ACPI_EC_COMMAND_COMPLETE); 706 wakeup = true; 707 if (t->command == ACPI_EC_COMMAND_QUERY) 708 ec_dbg_evt("Command(%s) completed by hardware", 709 acpi_ec_cmd_string(ACPI_EC_COMMAND_QUERY)); 710 } 711 } else if (interrupt && !(status & ACPI_EC_FLAG_SCI)) { 712 acpi_ec_spurious_interrupt(ec, t); 713 } 714 } else if (t->wlen == t->wi && !(status & ACPI_EC_FLAG_IBF)) { 715 ec_transaction_transition(ec, ACPI_EC_COMMAND_COMPLETE); 716 wakeup = true; 717 } 718 } else if (!(status & ACPI_EC_FLAG_IBF)) { 719 acpi_ec_write_cmd(ec, t->command); 720 ec_transaction_transition(ec, ACPI_EC_COMMAND_POLL); 721 } 722 723 out: 724 if (status & ACPI_EC_FLAG_SCI) 725 acpi_ec_submit_event(ec); 726 727 if (wakeup && interrupt) 728 wake_up(&ec->wait); 729 } 730 731 static void start_transaction(struct acpi_ec *ec) 732 { 733 ec->curr->irq_count = ec->curr->wi = ec->curr->ri = 0; 734 ec->curr->flags = 0; 735 } 736 737 static int ec_guard(struct acpi_ec *ec) 738 { 739 unsigned long guard = usecs_to_jiffies(ec->polling_guard); 740 unsigned long timeout = ec->timestamp + guard; 741 742 /* Ensure guarding period before polling EC status */ 743 do { 744 if (ec->busy_polling) { 745 /* Perform busy polling */ 746 if (ec_transaction_completed(ec)) 747 return 0; 748 udelay(jiffies_to_usecs(guard)); 749 } else { 750 /* 751 * Perform wait polling 752 * 1. Wait the transaction to be completed by the 753 * GPE handler after the transaction enters 754 * ACPI_EC_COMMAND_POLL state. 755 * 2. A special guarding logic is also required 756 * for event clearing mode "event" before the 757 * transaction enters ACPI_EC_COMMAND_POLL 758 * state. 759 */ 760 if (!ec_transaction_polled(ec) && 761 !acpi_ec_guard_event(ec)) 762 break; 763 if (wait_event_timeout(ec->wait, 764 ec_transaction_completed(ec), 765 guard)) 766 return 0; 767 } 768 } while (time_before(jiffies, timeout)); 769 return -ETIME; 770 } 771 772 static int ec_poll(struct acpi_ec *ec) 773 { 774 unsigned long flags; 775 int repeat = 5; /* number of command restarts */ 776 777 while (repeat--) { 778 unsigned long delay = jiffies + 779 msecs_to_jiffies(ec_delay); 780 do { 781 if (!ec_guard(ec)) 782 return 0; 783 spin_lock_irqsave(&ec->lock, flags); 784 advance_transaction(ec, false); 785 spin_unlock_irqrestore(&ec->lock, flags); 786 } while (time_before(jiffies, delay)); 787 pr_debug("controller reset, restart transaction\n"); 788 spin_lock_irqsave(&ec->lock, flags); 789 start_transaction(ec); 790 spin_unlock_irqrestore(&ec->lock, flags); 791 } 792 return -ETIME; 793 } 794 795 static int acpi_ec_transaction_unlocked(struct acpi_ec *ec, 796 struct transaction *t) 797 { 798 unsigned long tmp; 799 int ret = 0; 800 801 /* start transaction */ 802 spin_lock_irqsave(&ec->lock, tmp); 803 /* Enable GPE for command processing (IBF=0/OBF=1) */ 804 if (!acpi_ec_submit_flushable_request(ec)) { 805 ret = -EINVAL; 806 goto unlock; 807 } 808 ec_dbg_ref(ec, "Increase command"); 809 /* following two actions should be kept atomic */ 810 ec->curr = t; 811 ec_dbg_req("Command(%s) started", acpi_ec_cmd_string(t->command)); 812 start_transaction(ec); 813 spin_unlock_irqrestore(&ec->lock, tmp); 814 815 ret = ec_poll(ec); 816 817 spin_lock_irqsave(&ec->lock, tmp); 818 if (t->irq_count == ec_storm_threshold) 819 acpi_ec_unmask_events(ec); 820 ec_dbg_req("Command(%s) stopped", acpi_ec_cmd_string(t->command)); 821 ec->curr = NULL; 822 /* Disable GPE for command processing (IBF=0/OBF=1) */ 823 acpi_ec_complete_request(ec); 824 ec_dbg_ref(ec, "Decrease command"); 825 unlock: 826 spin_unlock_irqrestore(&ec->lock, tmp); 827 return ret; 828 } 829 830 static int acpi_ec_transaction(struct acpi_ec *ec, struct transaction *t) 831 { 832 int status; 833 u32 glk; 834 835 if (!ec || (!t) || (t->wlen && !t->wdata) || (t->rlen && !t->rdata)) 836 return -EINVAL; 837 if (t->rdata) 838 memset(t->rdata, 0, t->rlen); 839 840 mutex_lock(&ec->mutex); 841 if (ec->global_lock) { 842 status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk); 843 if (ACPI_FAILURE(status)) { 844 status = -ENODEV; 845 goto unlock; 846 } 847 } 848 849 status = acpi_ec_transaction_unlocked(ec, t); 850 851 if (ec->global_lock) 852 acpi_release_global_lock(glk); 853 unlock: 854 mutex_unlock(&ec->mutex); 855 return status; 856 } 857 858 static int acpi_ec_burst_enable(struct acpi_ec *ec) 859 { 860 u8 d; 861 struct transaction t = {.command = ACPI_EC_BURST_ENABLE, 862 .wdata = NULL, .rdata = &d, 863 .wlen = 0, .rlen = 1}; 864 865 return acpi_ec_transaction(ec, &t); 866 } 867 868 static int acpi_ec_burst_disable(struct acpi_ec *ec) 869 { 870 struct transaction t = {.command = ACPI_EC_BURST_DISABLE, 871 .wdata = NULL, .rdata = NULL, 872 .wlen = 0, .rlen = 0}; 873 874 return (acpi_ec_read_status(ec) & ACPI_EC_FLAG_BURST) ? 875 acpi_ec_transaction(ec, &t) : 0; 876 } 877 878 static int acpi_ec_read(struct acpi_ec *ec, u8 address, u8 *data) 879 { 880 int result; 881 u8 d; 882 struct transaction t = {.command = ACPI_EC_COMMAND_READ, 883 .wdata = &address, .rdata = &d, 884 .wlen = 1, .rlen = 1}; 885 886 result = acpi_ec_transaction(ec, &t); 887 *data = d; 888 return result; 889 } 890 891 static int acpi_ec_write(struct acpi_ec *ec, u8 address, u8 data) 892 { 893 u8 wdata[2] = { address, data }; 894 struct transaction t = {.command = ACPI_EC_COMMAND_WRITE, 895 .wdata = wdata, .rdata = NULL, 896 .wlen = 2, .rlen = 0}; 897 898 return acpi_ec_transaction(ec, &t); 899 } 900 901 int ec_read(u8 addr, u8 *val) 902 { 903 int err; 904 u8 temp_data; 905 906 if (!first_ec) 907 return -ENODEV; 908 909 err = acpi_ec_read(first_ec, addr, &temp_data); 910 911 if (!err) { 912 *val = temp_data; 913 return 0; 914 } 915 return err; 916 } 917 EXPORT_SYMBOL(ec_read); 918 919 int ec_write(u8 addr, u8 val) 920 { 921 if (!first_ec) 922 return -ENODEV; 923 924 return acpi_ec_write(first_ec, addr, val); 925 } 926 EXPORT_SYMBOL(ec_write); 927 928 int ec_transaction(u8 command, 929 const u8 *wdata, unsigned wdata_len, 930 u8 *rdata, unsigned rdata_len) 931 { 932 struct transaction t = {.command = command, 933 .wdata = wdata, .rdata = rdata, 934 .wlen = wdata_len, .rlen = rdata_len}; 935 936 if (!first_ec) 937 return -ENODEV; 938 939 return acpi_ec_transaction(first_ec, &t); 940 } 941 EXPORT_SYMBOL(ec_transaction); 942 943 /* Get the handle to the EC device */ 944 acpi_handle ec_get_handle(void) 945 { 946 if (!first_ec) 947 return NULL; 948 return first_ec->handle; 949 } 950 EXPORT_SYMBOL(ec_get_handle); 951 952 static void acpi_ec_start(struct acpi_ec *ec, bool resuming) 953 { 954 unsigned long flags; 955 956 spin_lock_irqsave(&ec->lock, flags); 957 if (!test_and_set_bit(EC_FLAGS_STARTED, &ec->flags)) { 958 ec_dbg_drv("Starting EC"); 959 /* Enable GPE for event processing (SCI_EVT=1) */ 960 if (!resuming) { 961 acpi_ec_submit_request(ec); 962 ec_dbg_ref(ec, "Increase driver"); 963 } 964 ec_log_drv("EC started"); 965 } 966 spin_unlock_irqrestore(&ec->lock, flags); 967 } 968 969 static bool acpi_ec_stopped(struct acpi_ec *ec) 970 { 971 unsigned long flags; 972 bool flushed; 973 974 spin_lock_irqsave(&ec->lock, flags); 975 flushed = acpi_ec_flushed(ec); 976 spin_unlock_irqrestore(&ec->lock, flags); 977 return flushed; 978 } 979 980 static void acpi_ec_stop(struct acpi_ec *ec, bool suspending) 981 { 982 unsigned long flags; 983 984 spin_lock_irqsave(&ec->lock, flags); 985 if (acpi_ec_started(ec)) { 986 ec_dbg_drv("Stopping EC"); 987 set_bit(EC_FLAGS_STOPPED, &ec->flags); 988 spin_unlock_irqrestore(&ec->lock, flags); 989 wait_event(ec->wait, acpi_ec_stopped(ec)); 990 spin_lock_irqsave(&ec->lock, flags); 991 /* Disable GPE for event processing (SCI_EVT=1) */ 992 if (!suspending) { 993 acpi_ec_complete_request(ec); 994 ec_dbg_ref(ec, "Decrease driver"); 995 } else if (!ec_freeze_events) 996 __acpi_ec_disable_event(ec); 997 clear_bit(EC_FLAGS_STARTED, &ec->flags); 998 clear_bit(EC_FLAGS_STOPPED, &ec->flags); 999 ec_log_drv("EC stopped"); 1000 } 1001 spin_unlock_irqrestore(&ec->lock, flags); 1002 } 1003 1004 static void acpi_ec_enter_noirq(struct acpi_ec *ec) 1005 { 1006 unsigned long flags; 1007 1008 spin_lock_irqsave(&ec->lock, flags); 1009 ec->busy_polling = true; 1010 ec->polling_guard = 0; 1011 ec_log_drv("interrupt blocked"); 1012 spin_unlock_irqrestore(&ec->lock, flags); 1013 } 1014 1015 static void acpi_ec_leave_noirq(struct acpi_ec *ec) 1016 { 1017 unsigned long flags; 1018 1019 spin_lock_irqsave(&ec->lock, flags); 1020 ec->busy_polling = ec_busy_polling; 1021 ec->polling_guard = ec_polling_guard; 1022 ec_log_drv("interrupt unblocked"); 1023 spin_unlock_irqrestore(&ec->lock, flags); 1024 } 1025 1026 void acpi_ec_block_transactions(void) 1027 { 1028 struct acpi_ec *ec = first_ec; 1029 1030 if (!ec) 1031 return; 1032 1033 mutex_lock(&ec->mutex); 1034 /* Prevent transactions from being carried out */ 1035 acpi_ec_stop(ec, true); 1036 mutex_unlock(&ec->mutex); 1037 } 1038 1039 void acpi_ec_unblock_transactions(void) 1040 { 1041 /* 1042 * Allow transactions to happen again (this function is called from 1043 * atomic context during wakeup, so we don't need to acquire the mutex). 1044 */ 1045 if (first_ec) 1046 acpi_ec_start(first_ec, true); 1047 } 1048 1049 /* -------------------------------------------------------------------------- 1050 Event Management 1051 -------------------------------------------------------------------------- */ 1052 static struct acpi_ec_query_handler * 1053 acpi_ec_get_query_handler_by_value(struct acpi_ec *ec, u8 value) 1054 { 1055 struct acpi_ec_query_handler *handler; 1056 1057 mutex_lock(&ec->mutex); 1058 list_for_each_entry(handler, &ec->list, node) { 1059 if (value == handler->query_bit) { 1060 kref_get(&handler->kref); 1061 mutex_unlock(&ec->mutex); 1062 return handler; 1063 } 1064 } 1065 mutex_unlock(&ec->mutex); 1066 return NULL; 1067 } 1068 1069 static void acpi_ec_query_handler_release(struct kref *kref) 1070 { 1071 struct acpi_ec_query_handler *handler = 1072 container_of(kref, struct acpi_ec_query_handler, kref); 1073 1074 kfree(handler); 1075 } 1076 1077 static void acpi_ec_put_query_handler(struct acpi_ec_query_handler *handler) 1078 { 1079 kref_put(&handler->kref, acpi_ec_query_handler_release); 1080 } 1081 1082 int acpi_ec_add_query_handler(struct acpi_ec *ec, u8 query_bit, 1083 acpi_handle handle, acpi_ec_query_func func, 1084 void *data) 1085 { 1086 struct acpi_ec_query_handler *handler; 1087 1088 if (!handle && !func) 1089 return -EINVAL; 1090 1091 handler = kzalloc(sizeof(*handler), GFP_KERNEL); 1092 if (!handler) 1093 return -ENOMEM; 1094 1095 handler->query_bit = query_bit; 1096 handler->handle = handle; 1097 handler->func = func; 1098 handler->data = data; 1099 mutex_lock(&ec->mutex); 1100 kref_init(&handler->kref); 1101 list_add(&handler->node, &ec->list); 1102 mutex_unlock(&ec->mutex); 1103 1104 return 0; 1105 } 1106 EXPORT_SYMBOL_GPL(acpi_ec_add_query_handler); 1107 1108 static void acpi_ec_remove_query_handlers(struct acpi_ec *ec, 1109 bool remove_all, u8 query_bit) 1110 { 1111 struct acpi_ec_query_handler *handler, *tmp; 1112 LIST_HEAD(free_list); 1113 1114 mutex_lock(&ec->mutex); 1115 list_for_each_entry_safe(handler, tmp, &ec->list, node) { 1116 /* 1117 * When remove_all is false, only remove custom query handlers 1118 * which have handler->func set. This is done to preserve query 1119 * handlers discovered thru ACPI, as they should continue handling 1120 * EC queries. 1121 */ 1122 if (remove_all || (handler->func && handler->query_bit == query_bit)) { 1123 list_del_init(&handler->node); 1124 list_add(&handler->node, &free_list); 1125 1126 } 1127 } 1128 mutex_unlock(&ec->mutex); 1129 list_for_each_entry_safe(handler, tmp, &free_list, node) 1130 acpi_ec_put_query_handler(handler); 1131 } 1132 1133 void acpi_ec_remove_query_handler(struct acpi_ec *ec, u8 query_bit) 1134 { 1135 acpi_ec_remove_query_handlers(ec, false, query_bit); 1136 flush_workqueue(ec_query_wq); 1137 } 1138 EXPORT_SYMBOL_GPL(acpi_ec_remove_query_handler); 1139 1140 static void acpi_ec_event_processor(struct work_struct *work) 1141 { 1142 struct acpi_ec_query *q = container_of(work, struct acpi_ec_query, work); 1143 struct acpi_ec_query_handler *handler = q->handler; 1144 struct acpi_ec *ec = q->ec; 1145 1146 ec_dbg_evt("Query(0x%02x) started", handler->query_bit); 1147 1148 if (handler->func) 1149 handler->func(handler->data); 1150 else if (handler->handle) 1151 acpi_evaluate_object(handler->handle, NULL, NULL, NULL); 1152 1153 ec_dbg_evt("Query(0x%02x) stopped", handler->query_bit); 1154 1155 spin_lock_irq(&ec->lock); 1156 ec->queries_in_progress--; 1157 spin_unlock_irq(&ec->lock); 1158 1159 acpi_ec_put_query_handler(handler); 1160 kfree(q); 1161 } 1162 1163 static struct acpi_ec_query *acpi_ec_create_query(struct acpi_ec *ec, u8 *pval) 1164 { 1165 struct acpi_ec_query *q; 1166 struct transaction *t; 1167 1168 q = kzalloc(sizeof (struct acpi_ec_query), GFP_KERNEL); 1169 if (!q) 1170 return NULL; 1171 1172 INIT_WORK(&q->work, acpi_ec_event_processor); 1173 t = &q->transaction; 1174 t->command = ACPI_EC_COMMAND_QUERY; 1175 t->rdata = pval; 1176 t->rlen = 1; 1177 q->ec = ec; 1178 return q; 1179 } 1180 1181 static int acpi_ec_submit_query(struct acpi_ec *ec) 1182 { 1183 struct acpi_ec_query *q; 1184 u8 value = 0; 1185 int result; 1186 1187 q = acpi_ec_create_query(ec, &value); 1188 if (!q) 1189 return -ENOMEM; 1190 1191 /* 1192 * Query the EC to find out which _Qxx method we need to evaluate. 1193 * Note that successful completion of the query causes the ACPI_EC_SCI 1194 * bit to be cleared (and thus clearing the interrupt source). 1195 */ 1196 result = acpi_ec_transaction(ec, &q->transaction); 1197 if (result) 1198 goto err_exit; 1199 1200 if (!value) { 1201 result = -ENODATA; 1202 goto err_exit; 1203 } 1204 1205 q->handler = acpi_ec_get_query_handler_by_value(ec, value); 1206 if (!q->handler) { 1207 result = -ENODATA; 1208 goto err_exit; 1209 } 1210 1211 /* 1212 * It is reported that _Qxx are evaluated in a parallel way on Windows: 1213 * https://bugzilla.kernel.org/show_bug.cgi?id=94411 1214 * 1215 * Put this log entry before queue_work() to make it appear in the log 1216 * before any other messages emitted during workqueue handling. 1217 */ 1218 ec_dbg_evt("Query(0x%02x) scheduled", value); 1219 1220 spin_lock_irq(&ec->lock); 1221 1222 ec->queries_in_progress++; 1223 queue_work(ec_query_wq, &q->work); 1224 1225 spin_unlock_irq(&ec->lock); 1226 1227 return 0; 1228 1229 err_exit: 1230 kfree(q); 1231 1232 return result; 1233 } 1234 1235 static void acpi_ec_event_handler(struct work_struct *work) 1236 { 1237 struct acpi_ec *ec = container_of(work, struct acpi_ec, work); 1238 1239 ec_dbg_evt("Event started"); 1240 1241 spin_lock_irq(&ec->lock); 1242 1243 while (ec->events_to_process) { 1244 spin_unlock_irq(&ec->lock); 1245 1246 acpi_ec_submit_query(ec); 1247 1248 spin_lock_irq(&ec->lock); 1249 1250 ec->events_to_process--; 1251 } 1252 1253 /* 1254 * Before exit, make sure that the it will be possible to queue up the 1255 * event handling work again regardless of whether or not the query 1256 * queued up above is processed successfully. 1257 */ 1258 if (ec_event_clearing == ACPI_EC_EVT_TIMING_EVENT) { 1259 bool guard_timeout; 1260 1261 acpi_ec_complete_event(ec); 1262 1263 ec_dbg_evt("Event stopped"); 1264 1265 spin_unlock_irq(&ec->lock); 1266 1267 guard_timeout = !!ec_guard(ec); 1268 1269 spin_lock_irq(&ec->lock); 1270 1271 /* Take care of SCI_EVT unless someone else is doing that. */ 1272 if (guard_timeout && !ec->curr) 1273 advance_transaction(ec, false); 1274 } else { 1275 acpi_ec_close_event(ec); 1276 1277 ec_dbg_evt("Event stopped"); 1278 } 1279 1280 ec->events_in_progress--; 1281 1282 spin_unlock_irq(&ec->lock); 1283 } 1284 1285 static void acpi_ec_handle_interrupt(struct acpi_ec *ec) 1286 { 1287 unsigned long flags; 1288 1289 spin_lock_irqsave(&ec->lock, flags); 1290 advance_transaction(ec, true); 1291 spin_unlock_irqrestore(&ec->lock, flags); 1292 } 1293 1294 static u32 acpi_ec_gpe_handler(acpi_handle gpe_device, 1295 u32 gpe_number, void *data) 1296 { 1297 acpi_ec_handle_interrupt(data); 1298 return ACPI_INTERRUPT_HANDLED; 1299 } 1300 1301 static irqreturn_t acpi_ec_irq_handler(int irq, void *data) 1302 { 1303 acpi_ec_handle_interrupt(data); 1304 return IRQ_HANDLED; 1305 } 1306 1307 /* -------------------------------------------------------------------------- 1308 * Address Space Management 1309 * -------------------------------------------------------------------------- */ 1310 1311 static acpi_status 1312 acpi_ec_space_handler(u32 function, acpi_physical_address address, 1313 u32 bits, u64 *value64, 1314 void *handler_context, void *region_context) 1315 { 1316 struct acpi_ec *ec = handler_context; 1317 int result = 0, i, bytes = bits / 8; 1318 u8 *value = (u8 *)value64; 1319 1320 if ((address > 0xFF) || !value || !handler_context) 1321 return AE_BAD_PARAMETER; 1322 1323 if (function != ACPI_READ && function != ACPI_WRITE) 1324 return AE_BAD_PARAMETER; 1325 1326 if (ec->busy_polling || bits > 8) 1327 acpi_ec_burst_enable(ec); 1328 1329 for (i = 0; i < bytes; ++i, ++address, ++value) 1330 result = (function == ACPI_READ) ? 1331 acpi_ec_read(ec, address, value) : 1332 acpi_ec_write(ec, address, *value); 1333 1334 if (ec->busy_polling || bits > 8) 1335 acpi_ec_burst_disable(ec); 1336 1337 switch (result) { 1338 case -EINVAL: 1339 return AE_BAD_PARAMETER; 1340 case -ENODEV: 1341 return AE_NOT_FOUND; 1342 case -ETIME: 1343 return AE_TIME; 1344 default: 1345 return AE_OK; 1346 } 1347 } 1348 1349 /* -------------------------------------------------------------------------- 1350 * Driver Interface 1351 * -------------------------------------------------------------------------- */ 1352 1353 static acpi_status 1354 ec_parse_io_ports(struct acpi_resource *resource, void *context); 1355 1356 static void acpi_ec_free(struct acpi_ec *ec) 1357 { 1358 if (first_ec == ec) 1359 first_ec = NULL; 1360 if (boot_ec == ec) 1361 boot_ec = NULL; 1362 kfree(ec); 1363 } 1364 1365 static struct acpi_ec *acpi_ec_alloc(void) 1366 { 1367 struct acpi_ec *ec = kzalloc(sizeof(struct acpi_ec), GFP_KERNEL); 1368 1369 if (!ec) 1370 return NULL; 1371 mutex_init(&ec->mutex); 1372 init_waitqueue_head(&ec->wait); 1373 INIT_LIST_HEAD(&ec->list); 1374 spin_lock_init(&ec->lock); 1375 INIT_WORK(&ec->work, acpi_ec_event_handler); 1376 ec->timestamp = jiffies; 1377 ec->busy_polling = true; 1378 ec->polling_guard = 0; 1379 ec->gpe = -1; 1380 ec->irq = -1; 1381 return ec; 1382 } 1383 1384 static acpi_status 1385 acpi_ec_register_query_methods(acpi_handle handle, u32 level, 1386 void *context, void **return_value) 1387 { 1388 char node_name[5]; 1389 struct acpi_buffer buffer = { sizeof(node_name), node_name }; 1390 struct acpi_ec *ec = context; 1391 int value = 0; 1392 acpi_status status; 1393 1394 status = acpi_get_name(handle, ACPI_SINGLE_NAME, &buffer); 1395 1396 if (ACPI_SUCCESS(status) && sscanf(node_name, "_Q%x", &value) == 1) 1397 acpi_ec_add_query_handler(ec, value, handle, NULL, NULL); 1398 return AE_OK; 1399 } 1400 1401 static acpi_status 1402 ec_parse_device(acpi_handle handle, u32 Level, void *context, void **retval) 1403 { 1404 acpi_status status; 1405 unsigned long long tmp = 0; 1406 struct acpi_ec *ec = context; 1407 1408 /* clear addr values, ec_parse_io_ports depend on it */ 1409 ec->command_addr = ec->data_addr = 0; 1410 1411 status = acpi_walk_resources(handle, METHOD_NAME__CRS, 1412 ec_parse_io_ports, ec); 1413 if (ACPI_FAILURE(status)) 1414 return status; 1415 if (ec->data_addr == 0 || ec->command_addr == 0) 1416 return AE_OK; 1417 1418 /* Get GPE bit assignment (EC events). */ 1419 /* TODO: Add support for _GPE returning a package */ 1420 status = acpi_evaluate_integer(handle, "_GPE", NULL, &tmp); 1421 if (ACPI_SUCCESS(status)) 1422 ec->gpe = tmp; 1423 /* 1424 * Errors are non-fatal, allowing for ACPI Reduced Hardware 1425 * platforms which use GpioInt instead of GPE. 1426 */ 1427 1428 /* Use the global lock for all EC transactions? */ 1429 tmp = 0; 1430 acpi_evaluate_integer(handle, "_GLK", NULL, &tmp); 1431 ec->global_lock = tmp; 1432 ec->handle = handle; 1433 return AE_CTRL_TERMINATE; 1434 } 1435 1436 static bool install_gpe_event_handler(struct acpi_ec *ec) 1437 { 1438 acpi_status status; 1439 1440 status = acpi_install_gpe_raw_handler(NULL, ec->gpe, 1441 ACPI_GPE_EDGE_TRIGGERED, 1442 &acpi_ec_gpe_handler, ec); 1443 if (ACPI_FAILURE(status)) 1444 return false; 1445 1446 if (test_bit(EC_FLAGS_STARTED, &ec->flags) && ec->reference_count >= 1) 1447 acpi_ec_enable_gpe(ec, true); 1448 1449 return true; 1450 } 1451 1452 static bool install_gpio_irq_event_handler(struct acpi_ec *ec) 1453 { 1454 return request_irq(ec->irq, acpi_ec_irq_handler, IRQF_SHARED, 1455 "ACPI EC", ec) >= 0; 1456 } 1457 1458 /** 1459 * ec_install_handlers - Install service callbacks and register query methods. 1460 * @ec: Target EC. 1461 * @device: ACPI device object corresponding to @ec. 1462 * @call_reg: If _REG should be called to notify OpRegion availability 1463 * 1464 * Install a handler for the EC address space type unless it has been installed 1465 * already. If @device is not NULL, also look for EC query methods in the 1466 * namespace and register them, and install an event (either GPE or GPIO IRQ) 1467 * handler for the EC, if possible. 1468 * 1469 * Return: 1470 * -ENODEV if the address space handler cannot be installed, which means 1471 * "unable to handle transactions", 1472 * -EPROBE_DEFER if GPIO IRQ acquisition needs to be deferred, 1473 * or 0 (success) otherwise. 1474 */ 1475 static int ec_install_handlers(struct acpi_ec *ec, struct acpi_device *device, 1476 bool call_reg) 1477 { 1478 acpi_status status; 1479 1480 acpi_ec_start(ec, false); 1481 1482 if (!test_bit(EC_FLAGS_EC_HANDLER_INSTALLED, &ec->flags)) { 1483 acpi_ec_enter_noirq(ec); 1484 status = acpi_install_address_space_handler_no_reg(ec->handle, 1485 ACPI_ADR_SPACE_EC, 1486 &acpi_ec_space_handler, 1487 NULL, ec); 1488 if (ACPI_FAILURE(status)) { 1489 acpi_ec_stop(ec, false); 1490 return -ENODEV; 1491 } 1492 set_bit(EC_FLAGS_EC_HANDLER_INSTALLED, &ec->flags); 1493 ec->address_space_handler_holder = ec->handle; 1494 } 1495 1496 if (call_reg && !test_bit(EC_FLAGS_EC_REG_CALLED, &ec->flags)) { 1497 acpi_execute_reg_methods(ec->handle, ACPI_ADR_SPACE_EC); 1498 set_bit(EC_FLAGS_EC_REG_CALLED, &ec->flags); 1499 } 1500 1501 if (!device) 1502 return 0; 1503 1504 if (ec->gpe < 0) { 1505 /* ACPI reduced hardware platforms use a GpioInt from _CRS. */ 1506 int irq = acpi_dev_gpio_irq_get(device, 0); 1507 /* 1508 * Bail out right away for deferred probing or complete the 1509 * initialization regardless of any other errors. 1510 */ 1511 if (irq == -EPROBE_DEFER) 1512 return -EPROBE_DEFER; 1513 else if (irq >= 0) 1514 ec->irq = irq; 1515 } 1516 1517 if (!test_bit(EC_FLAGS_QUERY_METHODS_INSTALLED, &ec->flags)) { 1518 /* Find and register all query methods */ 1519 acpi_walk_namespace(ACPI_TYPE_METHOD, ec->handle, 1, 1520 acpi_ec_register_query_methods, 1521 NULL, ec, NULL); 1522 set_bit(EC_FLAGS_QUERY_METHODS_INSTALLED, &ec->flags); 1523 } 1524 if (!test_bit(EC_FLAGS_EVENT_HANDLER_INSTALLED, &ec->flags)) { 1525 bool ready = false; 1526 1527 if (ec->gpe >= 0) 1528 ready = install_gpe_event_handler(ec); 1529 else if (ec->irq >= 0) 1530 ready = install_gpio_irq_event_handler(ec); 1531 1532 if (ready) { 1533 set_bit(EC_FLAGS_EVENT_HANDLER_INSTALLED, &ec->flags); 1534 acpi_ec_leave_noirq(ec); 1535 } 1536 /* 1537 * Failures to install an event handler are not fatal, because 1538 * the EC can be polled for events. 1539 */ 1540 } 1541 /* EC is fully operational, allow queries */ 1542 acpi_ec_enable_event(ec); 1543 1544 return 0; 1545 } 1546 1547 static void ec_remove_handlers(struct acpi_ec *ec) 1548 { 1549 if (test_bit(EC_FLAGS_EC_HANDLER_INSTALLED, &ec->flags)) { 1550 if (ACPI_FAILURE(acpi_remove_address_space_handler( 1551 ec->address_space_handler_holder, 1552 ACPI_ADR_SPACE_EC, &acpi_ec_space_handler))) 1553 pr_err("failed to remove space handler\n"); 1554 clear_bit(EC_FLAGS_EC_HANDLER_INSTALLED, &ec->flags); 1555 } 1556 1557 /* 1558 * Stops handling the EC transactions after removing the operation 1559 * region handler. This is required because _REG(DISCONNECT) 1560 * invoked during the removal can result in new EC transactions. 1561 * 1562 * Flushes the EC requests and thus disables the GPE before 1563 * removing the GPE handler. This is required by the current ACPICA 1564 * GPE core. ACPICA GPE core will automatically disable a GPE when 1565 * it is indicated but there is no way to handle it. So the drivers 1566 * must disable the GPEs prior to removing the GPE handlers. 1567 */ 1568 acpi_ec_stop(ec, false); 1569 1570 if (test_bit(EC_FLAGS_EVENT_HANDLER_INSTALLED, &ec->flags)) { 1571 if (ec->gpe >= 0 && 1572 ACPI_FAILURE(acpi_remove_gpe_handler(NULL, ec->gpe, 1573 &acpi_ec_gpe_handler))) 1574 pr_err("failed to remove gpe handler\n"); 1575 1576 if (ec->irq >= 0) 1577 free_irq(ec->irq, ec); 1578 1579 clear_bit(EC_FLAGS_EVENT_HANDLER_INSTALLED, &ec->flags); 1580 } 1581 if (test_bit(EC_FLAGS_QUERY_METHODS_INSTALLED, &ec->flags)) { 1582 acpi_ec_remove_query_handlers(ec, true, 0); 1583 clear_bit(EC_FLAGS_QUERY_METHODS_INSTALLED, &ec->flags); 1584 } 1585 } 1586 1587 static int acpi_ec_setup(struct acpi_ec *ec, struct acpi_device *device, bool call_reg) 1588 { 1589 int ret; 1590 1591 ret = ec_install_handlers(ec, device, call_reg); 1592 if (ret) 1593 return ret; 1594 1595 /* First EC capable of handling transactions */ 1596 if (!first_ec) 1597 first_ec = ec; 1598 1599 pr_info("EC_CMD/EC_SC=0x%lx, EC_DATA=0x%lx\n", ec->command_addr, 1600 ec->data_addr); 1601 1602 if (test_bit(EC_FLAGS_EVENT_HANDLER_INSTALLED, &ec->flags)) { 1603 if (ec->gpe >= 0) 1604 pr_info("GPE=0x%x\n", ec->gpe); 1605 else 1606 pr_info("IRQ=%d\n", ec->irq); 1607 } 1608 1609 return ret; 1610 } 1611 1612 static int acpi_ec_add(struct acpi_device *device) 1613 { 1614 struct acpi_ec *ec; 1615 int ret; 1616 1617 strcpy(acpi_device_name(device), ACPI_EC_DEVICE_NAME); 1618 strcpy(acpi_device_class(device), ACPI_EC_CLASS); 1619 1620 if (boot_ec && (boot_ec->handle == device->handle || 1621 !strcmp(acpi_device_hid(device), ACPI_ECDT_HID))) { 1622 /* Fast path: this device corresponds to the boot EC. */ 1623 ec = boot_ec; 1624 } else { 1625 acpi_status status; 1626 1627 ec = acpi_ec_alloc(); 1628 if (!ec) 1629 return -ENOMEM; 1630 1631 status = ec_parse_device(device->handle, 0, ec, NULL); 1632 if (status != AE_CTRL_TERMINATE) { 1633 ret = -EINVAL; 1634 goto err; 1635 } 1636 1637 if (boot_ec && ec->command_addr == boot_ec->command_addr && 1638 ec->data_addr == boot_ec->data_addr) { 1639 /* 1640 * Trust PNP0C09 namespace location rather than ECDT ID. 1641 * But trust ECDT GPE rather than _GPE because of ASUS 1642 * quirks. So do not change boot_ec->gpe to ec->gpe, 1643 * except when the TRUST_DSDT_GPE quirk is set. 1644 */ 1645 boot_ec->handle = ec->handle; 1646 1647 if (EC_FLAGS_TRUST_DSDT_GPE) 1648 boot_ec->gpe = ec->gpe; 1649 1650 acpi_handle_debug(ec->handle, "duplicated.\n"); 1651 acpi_ec_free(ec); 1652 ec = boot_ec; 1653 } 1654 } 1655 1656 ret = acpi_ec_setup(ec, device, true); 1657 if (ret) 1658 goto err; 1659 1660 if (ec == boot_ec) 1661 acpi_handle_info(boot_ec->handle, 1662 "Boot %s EC initialization complete\n", 1663 boot_ec_is_ecdt ? "ECDT" : "DSDT"); 1664 1665 acpi_handle_info(ec->handle, 1666 "EC: Used to handle transactions and events\n"); 1667 1668 device->driver_data = ec; 1669 1670 ret = !!request_region(ec->data_addr, 1, "EC data"); 1671 WARN(!ret, "Could not request EC data io port 0x%lx", ec->data_addr); 1672 ret = !!request_region(ec->command_addr, 1, "EC cmd"); 1673 WARN(!ret, "Could not request EC cmd io port 0x%lx", ec->command_addr); 1674 1675 /* Reprobe devices depending on the EC */ 1676 acpi_dev_clear_dependencies(device); 1677 1678 acpi_handle_debug(ec->handle, "enumerated.\n"); 1679 return 0; 1680 1681 err: 1682 if (ec != boot_ec) 1683 acpi_ec_free(ec); 1684 1685 return ret; 1686 } 1687 1688 static void acpi_ec_remove(struct acpi_device *device) 1689 { 1690 struct acpi_ec *ec; 1691 1692 if (!device) 1693 return; 1694 1695 ec = acpi_driver_data(device); 1696 release_region(ec->data_addr, 1); 1697 release_region(ec->command_addr, 1); 1698 device->driver_data = NULL; 1699 if (ec != boot_ec) { 1700 ec_remove_handlers(ec); 1701 acpi_ec_free(ec); 1702 } 1703 } 1704 1705 static acpi_status 1706 ec_parse_io_ports(struct acpi_resource *resource, void *context) 1707 { 1708 struct acpi_ec *ec = context; 1709 1710 if (resource->type != ACPI_RESOURCE_TYPE_IO) 1711 return AE_OK; 1712 1713 /* 1714 * The first address region returned is the data port, and 1715 * the second address region returned is the status/command 1716 * port. 1717 */ 1718 if (ec->data_addr == 0) 1719 ec->data_addr = resource->data.io.minimum; 1720 else if (ec->command_addr == 0) 1721 ec->command_addr = resource->data.io.minimum; 1722 else 1723 return AE_CTRL_TERMINATE; 1724 1725 return AE_OK; 1726 } 1727 1728 static const struct acpi_device_id ec_device_ids[] = { 1729 {"PNP0C09", 0}, 1730 {ACPI_ECDT_HID, 0}, 1731 {"", 0}, 1732 }; 1733 1734 /* 1735 * This function is not Windows-compatible as Windows never enumerates the 1736 * namespace EC before the main ACPI device enumeration process. It is 1737 * retained for historical reason and will be deprecated in the future. 1738 */ 1739 void __init acpi_ec_dsdt_probe(void) 1740 { 1741 struct acpi_ec *ec; 1742 acpi_status status; 1743 int ret; 1744 1745 /* 1746 * If a platform has ECDT, there is no need to proceed as the 1747 * following probe is not a part of the ACPI device enumeration, 1748 * executing _STA is not safe, and thus this probe may risk of 1749 * picking up an invalid EC device. 1750 */ 1751 if (boot_ec) 1752 return; 1753 1754 ec = acpi_ec_alloc(); 1755 if (!ec) 1756 return; 1757 1758 /* 1759 * At this point, the namespace is initialized, so start to find 1760 * the namespace objects. 1761 */ 1762 status = acpi_get_devices(ec_device_ids[0].id, ec_parse_device, ec, NULL); 1763 if (ACPI_FAILURE(status) || !ec->handle) { 1764 acpi_ec_free(ec); 1765 return; 1766 } 1767 1768 /* 1769 * When the DSDT EC is available, always re-configure boot EC to 1770 * have _REG evaluated. _REG can only be evaluated after the 1771 * namespace initialization. 1772 * At this point, the GPE is not fully initialized, so do not to 1773 * handle the events. 1774 */ 1775 ret = acpi_ec_setup(ec, NULL, true); 1776 if (ret) { 1777 acpi_ec_free(ec); 1778 return; 1779 } 1780 1781 boot_ec = ec; 1782 1783 acpi_handle_info(ec->handle, 1784 "Boot DSDT EC used to handle transactions\n"); 1785 } 1786 1787 /* 1788 * acpi_ec_ecdt_start - Finalize the boot ECDT EC initialization. 1789 * 1790 * First, look for an ACPI handle for the boot ECDT EC if acpi_ec_add() has not 1791 * found a matching object in the namespace. 1792 * 1793 * Next, in case the DSDT EC is not functioning, it is still necessary to 1794 * provide a functional ECDT EC to handle events, so add an extra device object 1795 * to represent it (see https://bugzilla.kernel.org/show_bug.cgi?id=115021). 1796 * 1797 * This is useful on platforms with valid ECDT and invalid DSDT EC settings, 1798 * like ASUS X550ZE (see https://bugzilla.kernel.org/show_bug.cgi?id=196847). 1799 */ 1800 static void __init acpi_ec_ecdt_start(void) 1801 { 1802 struct acpi_table_ecdt *ecdt_ptr; 1803 acpi_handle handle; 1804 acpi_status status; 1805 1806 /* Bail out if a matching EC has been found in the namespace. */ 1807 if (!boot_ec || boot_ec->handle != ACPI_ROOT_OBJECT) 1808 return; 1809 1810 /* Look up the object pointed to from the ECDT in the namespace. */ 1811 status = acpi_get_table(ACPI_SIG_ECDT, 1, 1812 (struct acpi_table_header **)&ecdt_ptr); 1813 if (ACPI_FAILURE(status)) 1814 return; 1815 1816 status = acpi_get_handle(NULL, ecdt_ptr->id, &handle); 1817 if (ACPI_SUCCESS(status)) { 1818 boot_ec->handle = handle; 1819 1820 /* Add a special ACPI device object to represent the boot EC. */ 1821 acpi_bus_register_early_device(ACPI_BUS_TYPE_ECDT_EC); 1822 } 1823 1824 acpi_put_table((struct acpi_table_header *)ecdt_ptr); 1825 } 1826 1827 /* 1828 * On some hardware it is necessary to clear events accumulated by the EC during 1829 * sleep. These ECs stop reporting GPEs until they are manually polled, if too 1830 * many events are accumulated. (e.g. Samsung Series 5/9 notebooks) 1831 * 1832 * https://bugzilla.kernel.org/show_bug.cgi?id=44161 1833 * 1834 * Ideally, the EC should also be instructed NOT to accumulate events during 1835 * sleep (which Windows seems to do somehow), but the interface to control this 1836 * behaviour is not known at this time. 1837 * 1838 * Models known to be affected are Samsung 530Uxx/535Uxx/540Uxx/550Pxx/900Xxx, 1839 * however it is very likely that other Samsung models are affected. 1840 * 1841 * On systems which don't accumulate _Q events during sleep, this extra check 1842 * should be harmless. 1843 */ 1844 static int ec_clear_on_resume(const struct dmi_system_id *id) 1845 { 1846 pr_debug("Detected system needing EC poll on resume.\n"); 1847 EC_FLAGS_CLEAR_ON_RESUME = 1; 1848 ec_event_clearing = ACPI_EC_EVT_TIMING_STATUS; 1849 return 0; 1850 } 1851 1852 /* 1853 * Some ECDTs contain wrong register addresses. 1854 * MSI MS-171F 1855 * https://bugzilla.kernel.org/show_bug.cgi?id=12461 1856 */ 1857 static int ec_correct_ecdt(const struct dmi_system_id *id) 1858 { 1859 pr_debug("Detected system needing ECDT address correction.\n"); 1860 EC_FLAGS_CORRECT_ECDT = 1; 1861 return 0; 1862 } 1863 1864 /* 1865 * Some ECDTs contain wrong GPE setting, but they share the same port addresses 1866 * with DSDT EC, don't duplicate the DSDT EC with ECDT EC in this case. 1867 * https://bugzilla.kernel.org/show_bug.cgi?id=209989 1868 */ 1869 static int ec_honor_dsdt_gpe(const struct dmi_system_id *id) 1870 { 1871 pr_debug("Detected system needing DSDT GPE setting.\n"); 1872 EC_FLAGS_TRUST_DSDT_GPE = 1; 1873 return 0; 1874 } 1875 1876 static const struct dmi_system_id ec_dmi_table[] __initconst = { 1877 { 1878 /* 1879 * MSI MS-171F 1880 * https://bugzilla.kernel.org/show_bug.cgi?id=12461 1881 */ 1882 .callback = ec_correct_ecdt, 1883 .matches = { 1884 DMI_MATCH(DMI_SYS_VENDOR, "Micro-Star"), 1885 DMI_MATCH(DMI_PRODUCT_NAME, "MS-171F"), 1886 }, 1887 }, 1888 { 1889 /* 1890 * HP Pavilion Gaming Laptop 15-cx0xxx 1891 * https://bugzilla.kernel.org/show_bug.cgi?id=209989 1892 */ 1893 .callback = ec_honor_dsdt_gpe, 1894 .matches = { 1895 DMI_MATCH(DMI_SYS_VENDOR, "HP"), 1896 DMI_MATCH(DMI_PRODUCT_NAME, "HP Pavilion Gaming Laptop 15-cx0xxx"), 1897 }, 1898 }, 1899 { 1900 /* 1901 * HP Pavilion Gaming Laptop 15-cx0041ur 1902 */ 1903 .callback = ec_honor_dsdt_gpe, 1904 .matches = { 1905 DMI_MATCH(DMI_SYS_VENDOR, "HP"), 1906 DMI_MATCH(DMI_PRODUCT_NAME, "HP 15-cx0041ur"), 1907 }, 1908 }, 1909 { 1910 /* 1911 * Samsung hardware 1912 * https://bugzilla.kernel.org/show_bug.cgi?id=44161 1913 */ 1914 .callback = ec_clear_on_resume, 1915 .matches = { 1916 DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."), 1917 }, 1918 }, 1919 {} 1920 }; 1921 1922 void __init acpi_ec_ecdt_probe(void) 1923 { 1924 struct acpi_table_ecdt *ecdt_ptr; 1925 struct acpi_ec *ec; 1926 acpi_status status; 1927 int ret; 1928 1929 /* Generate a boot ec context. */ 1930 dmi_check_system(ec_dmi_table); 1931 status = acpi_get_table(ACPI_SIG_ECDT, 1, 1932 (struct acpi_table_header **)&ecdt_ptr); 1933 if (ACPI_FAILURE(status)) 1934 return; 1935 1936 if (!ecdt_ptr->control.address || !ecdt_ptr->data.address) { 1937 /* 1938 * Asus X50GL: 1939 * https://bugzilla.kernel.org/show_bug.cgi?id=11880 1940 */ 1941 goto out; 1942 } 1943 1944 ec = acpi_ec_alloc(); 1945 if (!ec) 1946 goto out; 1947 1948 if (EC_FLAGS_CORRECT_ECDT) { 1949 ec->command_addr = ecdt_ptr->data.address; 1950 ec->data_addr = ecdt_ptr->control.address; 1951 } else { 1952 ec->command_addr = ecdt_ptr->control.address; 1953 ec->data_addr = ecdt_ptr->data.address; 1954 } 1955 1956 /* 1957 * Ignore the GPE value on Reduced Hardware platforms. 1958 * Some products have this set to an erroneous value. 1959 */ 1960 if (!acpi_gbl_reduced_hardware) 1961 ec->gpe = ecdt_ptr->gpe; 1962 1963 ec->handle = ACPI_ROOT_OBJECT; 1964 1965 /* 1966 * At this point, the namespace is not initialized, so do not find 1967 * the namespace objects, or handle the events. 1968 */ 1969 ret = acpi_ec_setup(ec, NULL, false); 1970 if (ret) { 1971 acpi_ec_free(ec); 1972 goto out; 1973 } 1974 1975 boot_ec = ec; 1976 boot_ec_is_ecdt = true; 1977 1978 pr_info("Boot ECDT EC used to handle transactions\n"); 1979 1980 out: 1981 acpi_put_table((struct acpi_table_header *)ecdt_ptr); 1982 } 1983 1984 #ifdef CONFIG_PM_SLEEP 1985 static int acpi_ec_suspend(struct device *dev) 1986 { 1987 struct acpi_ec *ec = 1988 acpi_driver_data(to_acpi_device(dev)); 1989 1990 if (!pm_suspend_no_platform() && ec_freeze_events) 1991 acpi_ec_disable_event(ec); 1992 return 0; 1993 } 1994 1995 static int acpi_ec_suspend_noirq(struct device *dev) 1996 { 1997 struct acpi_ec *ec = acpi_driver_data(to_acpi_device(dev)); 1998 1999 /* 2000 * The SCI handler doesn't run at this point, so the GPE can be 2001 * masked at the low level without side effects. 2002 */ 2003 if (ec_no_wakeup && test_bit(EC_FLAGS_STARTED, &ec->flags) && 2004 ec->gpe >= 0 && ec->reference_count >= 1) 2005 acpi_set_gpe(NULL, ec->gpe, ACPI_GPE_DISABLE); 2006 2007 acpi_ec_enter_noirq(ec); 2008 2009 return 0; 2010 } 2011 2012 static int acpi_ec_resume_noirq(struct device *dev) 2013 { 2014 struct acpi_ec *ec = acpi_driver_data(to_acpi_device(dev)); 2015 2016 acpi_ec_leave_noirq(ec); 2017 2018 if (ec_no_wakeup && test_bit(EC_FLAGS_STARTED, &ec->flags) && 2019 ec->gpe >= 0 && ec->reference_count >= 1) 2020 acpi_set_gpe(NULL, ec->gpe, ACPI_GPE_ENABLE); 2021 2022 return 0; 2023 } 2024 2025 static int acpi_ec_resume(struct device *dev) 2026 { 2027 struct acpi_ec *ec = 2028 acpi_driver_data(to_acpi_device(dev)); 2029 2030 acpi_ec_enable_event(ec); 2031 return 0; 2032 } 2033 2034 void acpi_ec_mark_gpe_for_wake(void) 2035 { 2036 if (first_ec && !ec_no_wakeup) 2037 acpi_mark_gpe_for_wake(NULL, first_ec->gpe); 2038 } 2039 EXPORT_SYMBOL_GPL(acpi_ec_mark_gpe_for_wake); 2040 2041 void acpi_ec_set_gpe_wake_mask(u8 action) 2042 { 2043 if (pm_suspend_no_platform() && first_ec && !ec_no_wakeup) 2044 acpi_set_gpe_wake_mask(NULL, first_ec->gpe, action); 2045 } 2046 2047 static bool acpi_ec_work_in_progress(struct acpi_ec *ec) 2048 { 2049 return ec->events_in_progress + ec->queries_in_progress > 0; 2050 } 2051 2052 bool acpi_ec_dispatch_gpe(void) 2053 { 2054 bool work_in_progress = false; 2055 2056 if (!first_ec) 2057 return acpi_any_gpe_status_set(U32_MAX); 2058 2059 /* 2060 * Report wakeup if the status bit is set for any enabled GPE other 2061 * than the EC one. 2062 */ 2063 if (acpi_any_gpe_status_set(first_ec->gpe)) 2064 return true; 2065 2066 /* 2067 * Cancel the SCI wakeup and process all pending events in case there 2068 * are any wakeup ones in there. 2069 * 2070 * Note that if any non-EC GPEs are active at this point, the SCI will 2071 * retrigger after the rearming in acpi_s2idle_wake(), so no events 2072 * should be missed by canceling the wakeup here. 2073 */ 2074 pm_system_cancel_wakeup(); 2075 2076 /* 2077 * Dispatch the EC GPE in-band, but do not report wakeup in any case 2078 * to allow the caller to process events properly after that. 2079 */ 2080 spin_lock_irq(&first_ec->lock); 2081 2082 if (acpi_ec_gpe_status_set(first_ec)) { 2083 pm_pr_dbg("ACPI EC GPE status set\n"); 2084 2085 advance_transaction(first_ec, false); 2086 work_in_progress = acpi_ec_work_in_progress(first_ec); 2087 } 2088 2089 spin_unlock_irq(&first_ec->lock); 2090 2091 if (!work_in_progress) 2092 return false; 2093 2094 pm_pr_dbg("ACPI EC GPE dispatched\n"); 2095 2096 /* Drain EC work. */ 2097 do { 2098 acpi_ec_flush_work(); 2099 2100 pm_pr_dbg("ACPI EC work flushed\n"); 2101 2102 spin_lock_irq(&first_ec->lock); 2103 2104 work_in_progress = acpi_ec_work_in_progress(first_ec); 2105 2106 spin_unlock_irq(&first_ec->lock); 2107 } while (work_in_progress && !pm_wakeup_pending()); 2108 2109 return false; 2110 } 2111 #endif /* CONFIG_PM_SLEEP */ 2112 2113 static const struct dev_pm_ops acpi_ec_pm = { 2114 SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(acpi_ec_suspend_noirq, acpi_ec_resume_noirq) 2115 SET_SYSTEM_SLEEP_PM_OPS(acpi_ec_suspend, acpi_ec_resume) 2116 }; 2117 2118 static int param_set_event_clearing(const char *val, 2119 const struct kernel_param *kp) 2120 { 2121 int result = 0; 2122 2123 if (!strncmp(val, "status", sizeof("status") - 1)) { 2124 ec_event_clearing = ACPI_EC_EVT_TIMING_STATUS; 2125 pr_info("Assuming SCI_EVT clearing on EC_SC accesses\n"); 2126 } else if (!strncmp(val, "query", sizeof("query") - 1)) { 2127 ec_event_clearing = ACPI_EC_EVT_TIMING_QUERY; 2128 pr_info("Assuming SCI_EVT clearing on QR_EC writes\n"); 2129 } else if (!strncmp(val, "event", sizeof("event") - 1)) { 2130 ec_event_clearing = ACPI_EC_EVT_TIMING_EVENT; 2131 pr_info("Assuming SCI_EVT clearing on event reads\n"); 2132 } else 2133 result = -EINVAL; 2134 return result; 2135 } 2136 2137 static int param_get_event_clearing(char *buffer, 2138 const struct kernel_param *kp) 2139 { 2140 switch (ec_event_clearing) { 2141 case ACPI_EC_EVT_TIMING_STATUS: 2142 return sprintf(buffer, "status\n"); 2143 case ACPI_EC_EVT_TIMING_QUERY: 2144 return sprintf(buffer, "query\n"); 2145 case ACPI_EC_EVT_TIMING_EVENT: 2146 return sprintf(buffer, "event\n"); 2147 default: 2148 return sprintf(buffer, "invalid\n"); 2149 } 2150 return 0; 2151 } 2152 2153 module_param_call(ec_event_clearing, param_set_event_clearing, param_get_event_clearing, 2154 NULL, 0644); 2155 MODULE_PARM_DESC(ec_event_clearing, "Assumed SCI_EVT clearing timing"); 2156 2157 static struct acpi_driver acpi_ec_driver = { 2158 .name = "ec", 2159 .class = ACPI_EC_CLASS, 2160 .ids = ec_device_ids, 2161 .ops = { 2162 .add = acpi_ec_add, 2163 .remove = acpi_ec_remove, 2164 }, 2165 .drv.pm = &acpi_ec_pm, 2166 }; 2167 2168 static void acpi_ec_destroy_workqueues(void) 2169 { 2170 if (ec_wq) { 2171 destroy_workqueue(ec_wq); 2172 ec_wq = NULL; 2173 } 2174 if (ec_query_wq) { 2175 destroy_workqueue(ec_query_wq); 2176 ec_query_wq = NULL; 2177 } 2178 } 2179 2180 static int acpi_ec_init_workqueues(void) 2181 { 2182 if (!ec_wq) 2183 ec_wq = alloc_ordered_workqueue("kec", 0); 2184 2185 if (!ec_query_wq) 2186 ec_query_wq = alloc_workqueue("kec_query", 0, ec_max_queries); 2187 2188 if (!ec_wq || !ec_query_wq) { 2189 acpi_ec_destroy_workqueues(); 2190 return -ENODEV; 2191 } 2192 return 0; 2193 } 2194 2195 static const struct dmi_system_id acpi_ec_no_wakeup[] = { 2196 { 2197 .matches = { 2198 DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"), 2199 DMI_MATCH(DMI_PRODUCT_FAMILY, "Thinkpad X1 Carbon 6th"), 2200 }, 2201 }, 2202 { 2203 .matches = { 2204 DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"), 2205 DMI_MATCH(DMI_PRODUCT_FAMILY, "ThinkPad X1 Yoga 3rd"), 2206 }, 2207 }, 2208 { 2209 .matches = { 2210 DMI_MATCH(DMI_SYS_VENDOR, "HP"), 2211 DMI_MATCH(DMI_PRODUCT_FAMILY, "103C_5336AN HP ZHAN 66 Pro"), 2212 }, 2213 }, 2214 { }, 2215 }; 2216 2217 void __init acpi_ec_init(void) 2218 { 2219 int result; 2220 2221 result = acpi_ec_init_workqueues(); 2222 if (result) 2223 return; 2224 2225 /* 2226 * Disable EC wakeup on following systems to prevent periodic 2227 * wakeup from EC GPE. 2228 */ 2229 if (dmi_check_system(acpi_ec_no_wakeup)) { 2230 ec_no_wakeup = true; 2231 pr_debug("Disabling EC wakeup on suspend-to-idle\n"); 2232 } 2233 2234 /* Driver must be registered after acpi_ec_init_workqueues(). */ 2235 acpi_bus_register_driver(&acpi_ec_driver); 2236 2237 acpi_ec_ecdt_start(); 2238 } 2239 2240 /* EC driver currently not unloadable */ 2241 #if 0 2242 static void __exit acpi_ec_exit(void) 2243 { 2244 2245 acpi_bus_unregister_driver(&acpi_ec_driver); 2246 acpi_ec_destroy_workqueues(); 2247 } 2248 #endif /* 0 */ 2249