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 spin_lock(&ec->lock); 529 if (acpi_ec_started(ec)) 530 __acpi_ec_enable_event(ec); 531 spin_unlock(&ec->lock); 532 533 /* Drain additional events if hardware requires that */ 534 if (EC_FLAGS_CLEAR_ON_RESUME) 535 acpi_ec_clear(ec); 536 } 537 538 #ifdef CONFIG_PM_SLEEP 539 static void __acpi_ec_flush_work(void) 540 { 541 flush_workqueue(ec_wq); /* flush ec->work */ 542 flush_workqueue(ec_query_wq); /* flush queries */ 543 } 544 545 static void acpi_ec_disable_event(struct acpi_ec *ec) 546 { 547 spin_lock(&ec->lock); 548 __acpi_ec_disable_event(ec); 549 spin_unlock(&ec->lock); 550 551 /* 552 * When ec_freeze_events is true, we need to flush events in 553 * the proper position before entering the noirq stage. 554 */ 555 __acpi_ec_flush_work(); 556 } 557 558 void acpi_ec_flush_work(void) 559 { 560 /* Without ec_wq there is nothing to flush. */ 561 if (!ec_wq) 562 return; 563 564 __acpi_ec_flush_work(); 565 } 566 #endif /* CONFIG_PM_SLEEP */ 567 568 static bool acpi_ec_guard_event(struct acpi_ec *ec) 569 { 570 bool guarded; 571 572 spin_lock(&ec->lock); 573 /* 574 * If firmware SCI_EVT clearing timing is "event", we actually 575 * don't know when the SCI_EVT will be cleared by firmware after 576 * evaluating _Qxx, so we need to re-check SCI_EVT after waiting an 577 * acceptable period. 578 * 579 * The guarding period is applicable if the event state is not 580 * EC_EVENT_READY, but otherwise if the current transaction is of the 581 * ACPI_EC_COMMAND_QUERY type, the guarding should have elapsed already 582 * and it should not be applied to let the transaction transition into 583 * the ACPI_EC_COMMAND_POLL state immediately. 584 */ 585 guarded = ec_event_clearing == ACPI_EC_EVT_TIMING_EVENT && 586 ec->event_state != EC_EVENT_READY && 587 (!ec->curr || ec->curr->command != ACPI_EC_COMMAND_QUERY); 588 spin_unlock(&ec->lock); 589 return guarded; 590 } 591 592 static int ec_transaction_polled(struct acpi_ec *ec) 593 { 594 int ret = 0; 595 596 spin_lock(&ec->lock); 597 if (ec->curr && (ec->curr->flags & ACPI_EC_COMMAND_POLL)) 598 ret = 1; 599 spin_unlock(&ec->lock); 600 return ret; 601 } 602 603 static int ec_transaction_completed(struct acpi_ec *ec) 604 { 605 int ret = 0; 606 607 spin_lock(&ec->lock); 608 if (ec->curr && (ec->curr->flags & ACPI_EC_COMMAND_COMPLETE)) 609 ret = 1; 610 spin_unlock(&ec->lock); 611 return ret; 612 } 613 614 static inline void ec_transaction_transition(struct acpi_ec *ec, unsigned long flag) 615 { 616 ec->curr->flags |= flag; 617 618 if (ec->curr->command != ACPI_EC_COMMAND_QUERY) 619 return; 620 621 switch (ec_event_clearing) { 622 case ACPI_EC_EVT_TIMING_STATUS: 623 if (flag == ACPI_EC_COMMAND_POLL) 624 acpi_ec_close_event(ec); 625 626 return; 627 628 case ACPI_EC_EVT_TIMING_QUERY: 629 if (flag == ACPI_EC_COMMAND_COMPLETE) 630 acpi_ec_close_event(ec); 631 632 return; 633 634 case ACPI_EC_EVT_TIMING_EVENT: 635 if (flag == ACPI_EC_COMMAND_COMPLETE) 636 acpi_ec_complete_event(ec); 637 } 638 } 639 640 static void acpi_ec_spurious_interrupt(struct acpi_ec *ec, struct transaction *t) 641 { 642 if (t->irq_count < ec_storm_threshold) 643 ++t->irq_count; 644 645 /* Trigger if the threshold is 0 too. */ 646 if (t->irq_count == ec_storm_threshold) 647 acpi_ec_mask_events(ec); 648 } 649 650 static void advance_transaction(struct acpi_ec *ec, bool interrupt) 651 { 652 struct transaction *t = ec->curr; 653 bool wakeup = false; 654 u8 status; 655 656 ec_dbg_stm("%s (%d)", interrupt ? "IRQ" : "TASK", smp_processor_id()); 657 658 status = acpi_ec_read_status(ec); 659 660 /* 661 * Another IRQ or a guarded polling mode advancement is detected, 662 * the next QR_EC submission is then allowed. 663 */ 664 if (!t || !(t->flags & ACPI_EC_COMMAND_POLL)) { 665 if (ec_event_clearing == ACPI_EC_EVT_TIMING_EVENT && 666 ec->event_state == EC_EVENT_COMPLETE) 667 acpi_ec_close_event(ec); 668 669 if (!t) 670 goto out; 671 } 672 673 if (t->flags & ACPI_EC_COMMAND_POLL) { 674 if (t->wlen > t->wi) { 675 if (!(status & ACPI_EC_FLAG_IBF)) 676 acpi_ec_write_data(ec, t->wdata[t->wi++]); 677 else if (interrupt && !(status & ACPI_EC_FLAG_SCI)) 678 acpi_ec_spurious_interrupt(ec, t); 679 } else if (t->rlen > t->ri) { 680 if (status & ACPI_EC_FLAG_OBF) { 681 t->rdata[t->ri++] = acpi_ec_read_data(ec); 682 if (t->rlen == t->ri) { 683 ec_transaction_transition(ec, ACPI_EC_COMMAND_COMPLETE); 684 wakeup = true; 685 if (t->command == ACPI_EC_COMMAND_QUERY) 686 ec_dbg_evt("Command(%s) completed by hardware", 687 acpi_ec_cmd_string(ACPI_EC_COMMAND_QUERY)); 688 } 689 } else if (interrupt && !(status & ACPI_EC_FLAG_SCI)) { 690 acpi_ec_spurious_interrupt(ec, t); 691 } 692 } else if (t->wlen == t->wi && !(status & ACPI_EC_FLAG_IBF)) { 693 ec_transaction_transition(ec, ACPI_EC_COMMAND_COMPLETE); 694 wakeup = true; 695 } 696 } else if (!(status & ACPI_EC_FLAG_IBF)) { 697 acpi_ec_write_cmd(ec, t->command); 698 ec_transaction_transition(ec, ACPI_EC_COMMAND_POLL); 699 } 700 701 out: 702 if (status & ACPI_EC_FLAG_SCI) 703 acpi_ec_submit_event(ec); 704 705 if (wakeup && interrupt) 706 wake_up(&ec->wait); 707 } 708 709 static void start_transaction(struct acpi_ec *ec) 710 { 711 ec->curr->irq_count = ec->curr->wi = ec->curr->ri = 0; 712 ec->curr->flags = 0; 713 } 714 715 static int ec_guard(struct acpi_ec *ec) 716 { 717 unsigned long guard = usecs_to_jiffies(ec->polling_guard); 718 unsigned long timeout = ec->timestamp + guard; 719 720 /* Ensure guarding period before polling EC status */ 721 do { 722 if (ec->busy_polling) { 723 /* Perform busy polling */ 724 if (ec_transaction_completed(ec)) 725 return 0; 726 udelay(jiffies_to_usecs(guard)); 727 } else { 728 /* 729 * Perform wait polling 730 * 1. Wait the transaction to be completed by the 731 * GPE handler after the transaction enters 732 * ACPI_EC_COMMAND_POLL state. 733 * 2. A special guarding logic is also required 734 * for event clearing mode "event" before the 735 * transaction enters ACPI_EC_COMMAND_POLL 736 * state. 737 */ 738 if (!ec_transaction_polled(ec) && 739 !acpi_ec_guard_event(ec)) 740 break; 741 if (wait_event_timeout(ec->wait, 742 ec_transaction_completed(ec), 743 guard)) 744 return 0; 745 } 746 } while (time_before(jiffies, timeout)); 747 return -ETIME; 748 } 749 750 static int ec_poll(struct acpi_ec *ec) 751 { 752 int repeat = 5; /* number of command restarts */ 753 754 while (repeat--) { 755 unsigned long delay = jiffies + 756 msecs_to_jiffies(ec_delay); 757 do { 758 if (!ec_guard(ec)) 759 return 0; 760 spin_lock(&ec->lock); 761 advance_transaction(ec, false); 762 spin_unlock(&ec->lock); 763 } while (time_before(jiffies, delay)); 764 pr_debug("controller reset, restart transaction\n"); 765 spin_lock(&ec->lock); 766 start_transaction(ec); 767 spin_unlock(&ec->lock); 768 } 769 return -ETIME; 770 } 771 772 static int acpi_ec_transaction_unlocked(struct acpi_ec *ec, 773 struct transaction *t) 774 { 775 int ret = 0; 776 777 /* start transaction */ 778 spin_lock(&ec->lock); 779 /* Enable GPE for command processing (IBF=0/OBF=1) */ 780 if (!acpi_ec_submit_flushable_request(ec)) { 781 ret = -EINVAL; 782 goto unlock; 783 } 784 ec_dbg_ref(ec, "Increase command"); 785 /* following two actions should be kept atomic */ 786 ec->curr = t; 787 ec_dbg_req("Command(%s) started", acpi_ec_cmd_string(t->command)); 788 start_transaction(ec); 789 spin_unlock(&ec->lock); 790 791 ret = ec_poll(ec); 792 793 spin_lock(&ec->lock); 794 if (t->irq_count == ec_storm_threshold) 795 acpi_ec_unmask_events(ec); 796 ec_dbg_req("Command(%s) stopped", acpi_ec_cmd_string(t->command)); 797 ec->curr = NULL; 798 /* Disable GPE for command processing (IBF=0/OBF=1) */ 799 acpi_ec_complete_request(ec); 800 ec_dbg_ref(ec, "Decrease command"); 801 unlock: 802 spin_unlock(&ec->lock); 803 return ret; 804 } 805 806 static int acpi_ec_transaction(struct acpi_ec *ec, struct transaction *t) 807 { 808 int status; 809 u32 glk; 810 811 if (!ec || (!t) || (t->wlen && !t->wdata) || (t->rlen && !t->rdata)) 812 return -EINVAL; 813 if (t->rdata) 814 memset(t->rdata, 0, t->rlen); 815 816 mutex_lock(&ec->mutex); 817 if (ec->global_lock) { 818 status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk); 819 if (ACPI_FAILURE(status)) { 820 status = -ENODEV; 821 goto unlock; 822 } 823 } 824 825 status = acpi_ec_transaction_unlocked(ec, t); 826 827 if (ec->global_lock) 828 acpi_release_global_lock(glk); 829 unlock: 830 mutex_unlock(&ec->mutex); 831 return status; 832 } 833 834 static int acpi_ec_burst_enable(struct acpi_ec *ec) 835 { 836 u8 d; 837 struct transaction t = {.command = ACPI_EC_BURST_ENABLE, 838 .wdata = NULL, .rdata = &d, 839 .wlen = 0, .rlen = 1}; 840 841 return acpi_ec_transaction(ec, &t); 842 } 843 844 static int acpi_ec_burst_disable(struct acpi_ec *ec) 845 { 846 struct transaction t = {.command = ACPI_EC_BURST_DISABLE, 847 .wdata = NULL, .rdata = NULL, 848 .wlen = 0, .rlen = 0}; 849 850 return (acpi_ec_read_status(ec) & ACPI_EC_FLAG_BURST) ? 851 acpi_ec_transaction(ec, &t) : 0; 852 } 853 854 static int acpi_ec_read(struct acpi_ec *ec, u8 address, u8 *data) 855 { 856 int result; 857 u8 d; 858 struct transaction t = {.command = ACPI_EC_COMMAND_READ, 859 .wdata = &address, .rdata = &d, 860 .wlen = 1, .rlen = 1}; 861 862 result = acpi_ec_transaction(ec, &t); 863 *data = d; 864 return result; 865 } 866 867 static int acpi_ec_write(struct acpi_ec *ec, u8 address, u8 data) 868 { 869 u8 wdata[2] = { address, data }; 870 struct transaction t = {.command = ACPI_EC_COMMAND_WRITE, 871 .wdata = wdata, .rdata = NULL, 872 .wlen = 2, .rlen = 0}; 873 874 return acpi_ec_transaction(ec, &t); 875 } 876 877 int ec_read(u8 addr, u8 *val) 878 { 879 int err; 880 u8 temp_data; 881 882 if (!first_ec) 883 return -ENODEV; 884 885 err = acpi_ec_read(first_ec, addr, &temp_data); 886 887 if (!err) { 888 *val = temp_data; 889 return 0; 890 } 891 return err; 892 } 893 EXPORT_SYMBOL(ec_read); 894 895 int ec_write(u8 addr, u8 val) 896 { 897 if (!first_ec) 898 return -ENODEV; 899 900 return acpi_ec_write(first_ec, addr, val); 901 } 902 EXPORT_SYMBOL(ec_write); 903 904 int ec_transaction(u8 command, 905 const u8 *wdata, unsigned wdata_len, 906 u8 *rdata, unsigned rdata_len) 907 { 908 struct transaction t = {.command = command, 909 .wdata = wdata, .rdata = rdata, 910 .wlen = wdata_len, .rlen = rdata_len}; 911 912 if (!first_ec) 913 return -ENODEV; 914 915 return acpi_ec_transaction(first_ec, &t); 916 } 917 EXPORT_SYMBOL(ec_transaction); 918 919 /* Get the handle to the EC device */ 920 acpi_handle ec_get_handle(void) 921 { 922 if (!first_ec) 923 return NULL; 924 return first_ec->handle; 925 } 926 EXPORT_SYMBOL(ec_get_handle); 927 928 static void acpi_ec_start(struct acpi_ec *ec, bool resuming) 929 { 930 spin_lock(&ec->lock); 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(&ec->lock); 941 } 942 943 static bool acpi_ec_stopped(struct acpi_ec *ec) 944 { 945 bool flushed; 946 947 spin_lock(&ec->lock); 948 flushed = acpi_ec_flushed(ec); 949 spin_unlock(&ec->lock); 950 return flushed; 951 } 952 953 static void acpi_ec_stop(struct acpi_ec *ec, bool suspending) 954 { 955 spin_lock(&ec->lock); 956 if (acpi_ec_started(ec)) { 957 ec_dbg_drv("Stopping EC"); 958 set_bit(EC_FLAGS_STOPPED, &ec->flags); 959 spin_unlock(&ec->lock); 960 wait_event(ec->wait, acpi_ec_stopped(ec)); 961 spin_lock(&ec->lock); 962 /* Disable GPE for event processing (SCI_EVT=1) */ 963 if (!suspending) { 964 acpi_ec_complete_request(ec); 965 ec_dbg_ref(ec, "Decrease driver"); 966 } else if (!ec_freeze_events) 967 __acpi_ec_disable_event(ec); 968 clear_bit(EC_FLAGS_STARTED, &ec->flags); 969 clear_bit(EC_FLAGS_STOPPED, &ec->flags); 970 ec_log_drv("EC stopped"); 971 } 972 spin_unlock(&ec->lock); 973 } 974 975 static void acpi_ec_enter_noirq(struct acpi_ec *ec) 976 { 977 spin_lock(&ec->lock); 978 ec->busy_polling = true; 979 ec->polling_guard = 0; 980 ec_log_drv("interrupt blocked"); 981 spin_unlock(&ec->lock); 982 } 983 984 static void acpi_ec_leave_noirq(struct acpi_ec *ec) 985 { 986 spin_lock(&ec->lock); 987 ec->busy_polling = ec_busy_polling; 988 ec->polling_guard = ec_polling_guard; 989 ec_log_drv("interrupt unblocked"); 990 spin_unlock(&ec->lock); 991 } 992 993 void acpi_ec_block_transactions(void) 994 { 995 struct acpi_ec *ec = first_ec; 996 997 if (!ec) 998 return; 999 1000 mutex_lock(&ec->mutex); 1001 /* Prevent transactions from being carried out */ 1002 acpi_ec_stop(ec, true); 1003 mutex_unlock(&ec->mutex); 1004 } 1005 1006 void acpi_ec_unblock_transactions(void) 1007 { 1008 /* 1009 * Allow transactions to happen again (this function is called from 1010 * atomic context during wakeup, so we don't need to acquire the mutex). 1011 */ 1012 if (first_ec) 1013 acpi_ec_start(first_ec, true); 1014 } 1015 1016 /* -------------------------------------------------------------------------- 1017 Event Management 1018 -------------------------------------------------------------------------- */ 1019 static struct acpi_ec_query_handler * 1020 acpi_ec_get_query_handler_by_value(struct acpi_ec *ec, u8 value) 1021 { 1022 struct acpi_ec_query_handler *handler; 1023 1024 mutex_lock(&ec->mutex); 1025 list_for_each_entry(handler, &ec->list, node) { 1026 if (value == handler->query_bit) { 1027 kref_get(&handler->kref); 1028 mutex_unlock(&ec->mutex); 1029 return handler; 1030 } 1031 } 1032 mutex_unlock(&ec->mutex); 1033 return NULL; 1034 } 1035 1036 static void acpi_ec_query_handler_release(struct kref *kref) 1037 { 1038 struct acpi_ec_query_handler *handler = 1039 container_of(kref, struct acpi_ec_query_handler, kref); 1040 1041 kfree(handler); 1042 } 1043 1044 static void acpi_ec_put_query_handler(struct acpi_ec_query_handler *handler) 1045 { 1046 kref_put(&handler->kref, acpi_ec_query_handler_release); 1047 } 1048 1049 int acpi_ec_add_query_handler(struct acpi_ec *ec, u8 query_bit, 1050 acpi_handle handle, acpi_ec_query_func func, 1051 void *data) 1052 { 1053 struct acpi_ec_query_handler *handler; 1054 1055 if (!handle && !func) 1056 return -EINVAL; 1057 1058 handler = kzalloc(sizeof(*handler), GFP_KERNEL); 1059 if (!handler) 1060 return -ENOMEM; 1061 1062 handler->query_bit = query_bit; 1063 handler->handle = handle; 1064 handler->func = func; 1065 handler->data = data; 1066 mutex_lock(&ec->mutex); 1067 kref_init(&handler->kref); 1068 list_add(&handler->node, &ec->list); 1069 mutex_unlock(&ec->mutex); 1070 1071 return 0; 1072 } 1073 EXPORT_SYMBOL_GPL(acpi_ec_add_query_handler); 1074 1075 static void acpi_ec_remove_query_handlers(struct acpi_ec *ec, 1076 bool remove_all, u8 query_bit) 1077 { 1078 struct acpi_ec_query_handler *handler, *tmp; 1079 LIST_HEAD(free_list); 1080 1081 mutex_lock(&ec->mutex); 1082 list_for_each_entry_safe(handler, tmp, &ec->list, node) { 1083 /* 1084 * When remove_all is false, only remove custom query handlers 1085 * which have handler->func set. This is done to preserve query 1086 * handlers discovered thru ACPI, as they should continue handling 1087 * EC queries. 1088 */ 1089 if (remove_all || (handler->func && handler->query_bit == query_bit)) { 1090 list_del_init(&handler->node); 1091 list_add(&handler->node, &free_list); 1092 1093 } 1094 } 1095 mutex_unlock(&ec->mutex); 1096 list_for_each_entry_safe(handler, tmp, &free_list, node) 1097 acpi_ec_put_query_handler(handler); 1098 } 1099 1100 void acpi_ec_remove_query_handler(struct acpi_ec *ec, u8 query_bit) 1101 { 1102 acpi_ec_remove_query_handlers(ec, false, query_bit); 1103 flush_workqueue(ec_query_wq); 1104 } 1105 EXPORT_SYMBOL_GPL(acpi_ec_remove_query_handler); 1106 1107 static void acpi_ec_event_processor(struct work_struct *work) 1108 { 1109 struct acpi_ec_query *q = container_of(work, struct acpi_ec_query, work); 1110 struct acpi_ec_query_handler *handler = q->handler; 1111 struct acpi_ec *ec = q->ec; 1112 1113 ec_dbg_evt("Query(0x%02x) started", handler->query_bit); 1114 1115 if (handler->func) 1116 handler->func(handler->data); 1117 else if (handler->handle) 1118 acpi_evaluate_object(handler->handle, NULL, NULL, NULL); 1119 1120 ec_dbg_evt("Query(0x%02x) stopped", handler->query_bit); 1121 1122 spin_lock(&ec->lock); 1123 ec->queries_in_progress--; 1124 spin_unlock(&ec->lock); 1125 1126 acpi_ec_put_query_handler(handler); 1127 kfree(q); 1128 } 1129 1130 static struct acpi_ec_query *acpi_ec_create_query(struct acpi_ec *ec, u8 *pval) 1131 { 1132 struct acpi_ec_query *q; 1133 struct transaction *t; 1134 1135 q = kzalloc(sizeof (struct acpi_ec_query), GFP_KERNEL); 1136 if (!q) 1137 return NULL; 1138 1139 INIT_WORK(&q->work, acpi_ec_event_processor); 1140 t = &q->transaction; 1141 t->command = ACPI_EC_COMMAND_QUERY; 1142 t->rdata = pval; 1143 t->rlen = 1; 1144 q->ec = ec; 1145 return q; 1146 } 1147 1148 static int acpi_ec_submit_query(struct acpi_ec *ec) 1149 { 1150 struct acpi_ec_query *q; 1151 u8 value = 0; 1152 int result; 1153 1154 q = acpi_ec_create_query(ec, &value); 1155 if (!q) 1156 return -ENOMEM; 1157 1158 /* 1159 * Query the EC to find out which _Qxx method we need to evaluate. 1160 * Note that successful completion of the query causes the ACPI_EC_SCI 1161 * bit to be cleared (and thus clearing the interrupt source). 1162 */ 1163 result = acpi_ec_transaction(ec, &q->transaction); 1164 if (result) 1165 goto err_exit; 1166 1167 if (!value) { 1168 result = -ENODATA; 1169 goto err_exit; 1170 } 1171 1172 q->handler = acpi_ec_get_query_handler_by_value(ec, value); 1173 if (!q->handler) { 1174 result = -ENODATA; 1175 goto err_exit; 1176 } 1177 1178 /* 1179 * It is reported that _Qxx are evaluated in a parallel way on Windows: 1180 * https://bugzilla.kernel.org/show_bug.cgi?id=94411 1181 * 1182 * Put this log entry before queue_work() to make it appear in the log 1183 * before any other messages emitted during workqueue handling. 1184 */ 1185 ec_dbg_evt("Query(0x%02x) scheduled", value); 1186 1187 spin_lock(&ec->lock); 1188 1189 ec->queries_in_progress++; 1190 queue_work(ec_query_wq, &q->work); 1191 1192 spin_unlock(&ec->lock); 1193 1194 return 0; 1195 1196 err_exit: 1197 kfree(q); 1198 1199 return result; 1200 } 1201 1202 static void acpi_ec_event_handler(struct work_struct *work) 1203 { 1204 struct acpi_ec *ec = container_of(work, struct acpi_ec, work); 1205 1206 ec_dbg_evt("Event started"); 1207 1208 spin_lock(&ec->lock); 1209 1210 while (ec->events_to_process) { 1211 spin_unlock(&ec->lock); 1212 1213 acpi_ec_submit_query(ec); 1214 1215 spin_lock(&ec->lock); 1216 1217 ec->events_to_process--; 1218 } 1219 1220 /* 1221 * Before exit, make sure that the it will be possible to queue up the 1222 * event handling work again regardless of whether or not the query 1223 * queued up above is processed successfully. 1224 */ 1225 if (ec_event_clearing == ACPI_EC_EVT_TIMING_EVENT) { 1226 bool guard_timeout; 1227 1228 acpi_ec_complete_event(ec); 1229 1230 ec_dbg_evt("Event stopped"); 1231 1232 spin_unlock(&ec->lock); 1233 1234 guard_timeout = !!ec_guard(ec); 1235 1236 spin_lock(&ec->lock); 1237 1238 /* Take care of SCI_EVT unless someone else is doing that. */ 1239 if (guard_timeout && !ec->curr) 1240 advance_transaction(ec, false); 1241 } else { 1242 acpi_ec_close_event(ec); 1243 1244 ec_dbg_evt("Event stopped"); 1245 } 1246 1247 ec->events_in_progress--; 1248 1249 spin_unlock(&ec->lock); 1250 } 1251 1252 static void clear_gpe_and_advance_transaction(struct acpi_ec *ec, bool interrupt) 1253 { 1254 /* 1255 * Clear GPE_STS upfront to allow subsequent hardware GPE_STS 0->1 1256 * changes to always trigger a GPE interrupt. 1257 * 1258 * GPE STS is a W1C register, which means: 1259 * 1260 * 1. Software can clear it without worrying about clearing the other 1261 * GPEs' STS bits when the hardware sets them in parallel. 1262 * 1263 * 2. As long as software can ensure only clearing it when it is set, 1264 * hardware won't set it in parallel. 1265 */ 1266 if (ec->gpe >= 0 && acpi_ec_gpe_status_set(ec)) 1267 acpi_clear_gpe(NULL, ec->gpe); 1268 1269 advance_transaction(ec, true); 1270 } 1271 1272 static void acpi_ec_handle_interrupt(struct acpi_ec *ec) 1273 { 1274 spin_lock(&ec->lock); 1275 1276 clear_gpe_and_advance_transaction(ec, true); 1277 1278 spin_unlock(&ec->lock); 1279 } 1280 1281 static u32 acpi_ec_gpe_handler(acpi_handle gpe_device, 1282 u32 gpe_number, void *data) 1283 { 1284 acpi_ec_handle_interrupt(data); 1285 return ACPI_INTERRUPT_HANDLED; 1286 } 1287 1288 static irqreturn_t acpi_ec_irq_handler(int irq, void *data) 1289 { 1290 acpi_ec_handle_interrupt(data); 1291 return IRQ_HANDLED; 1292 } 1293 1294 /* -------------------------------------------------------------------------- 1295 * Address Space Management 1296 * -------------------------------------------------------------------------- */ 1297 1298 static acpi_status 1299 acpi_ec_space_handler(u32 function, acpi_physical_address address, 1300 u32 bits, u64 *value64, 1301 void *handler_context, void *region_context) 1302 { 1303 struct acpi_ec *ec = handler_context; 1304 int result = 0, i, bytes = bits / 8; 1305 u8 *value = (u8 *)value64; 1306 1307 if ((address > 0xFF) || !value || !handler_context) 1308 return AE_BAD_PARAMETER; 1309 1310 if (function != ACPI_READ && function != ACPI_WRITE) 1311 return AE_BAD_PARAMETER; 1312 1313 if (ec->busy_polling || bits > 8) 1314 acpi_ec_burst_enable(ec); 1315 1316 for (i = 0; i < bytes; ++i, ++address, ++value) 1317 result = (function == ACPI_READ) ? 1318 acpi_ec_read(ec, address, value) : 1319 acpi_ec_write(ec, address, *value); 1320 1321 if (ec->busy_polling || bits > 8) 1322 acpi_ec_burst_disable(ec); 1323 1324 switch (result) { 1325 case -EINVAL: 1326 return AE_BAD_PARAMETER; 1327 case -ENODEV: 1328 return AE_NOT_FOUND; 1329 case -ETIME: 1330 return AE_TIME; 1331 default: 1332 return AE_OK; 1333 } 1334 } 1335 1336 /* -------------------------------------------------------------------------- 1337 * Driver Interface 1338 * -------------------------------------------------------------------------- */ 1339 1340 static acpi_status 1341 ec_parse_io_ports(struct acpi_resource *resource, void *context); 1342 1343 static void acpi_ec_free(struct acpi_ec *ec) 1344 { 1345 if (first_ec == ec) 1346 first_ec = NULL; 1347 if (boot_ec == ec) 1348 boot_ec = NULL; 1349 kfree(ec); 1350 } 1351 1352 static struct acpi_ec *acpi_ec_alloc(void) 1353 { 1354 struct acpi_ec *ec = kzalloc(sizeof(struct acpi_ec), GFP_KERNEL); 1355 1356 if (!ec) 1357 return NULL; 1358 mutex_init(&ec->mutex); 1359 init_waitqueue_head(&ec->wait); 1360 INIT_LIST_HEAD(&ec->list); 1361 spin_lock_init(&ec->lock); 1362 INIT_WORK(&ec->work, acpi_ec_event_handler); 1363 ec->timestamp = jiffies; 1364 ec->busy_polling = true; 1365 ec->polling_guard = 0; 1366 ec->gpe = -1; 1367 ec->irq = -1; 1368 return ec; 1369 } 1370 1371 static acpi_status 1372 acpi_ec_register_query_methods(acpi_handle handle, u32 level, 1373 void *context, void **return_value) 1374 { 1375 char node_name[5]; 1376 struct acpi_buffer buffer = { sizeof(node_name), node_name }; 1377 struct acpi_ec *ec = context; 1378 int value = 0; 1379 acpi_status status; 1380 1381 status = acpi_get_name(handle, ACPI_SINGLE_NAME, &buffer); 1382 1383 if (ACPI_SUCCESS(status) && sscanf(node_name, "_Q%x", &value) == 1) 1384 acpi_ec_add_query_handler(ec, value, handle, NULL, NULL); 1385 return AE_OK; 1386 } 1387 1388 static acpi_status 1389 ec_parse_device(acpi_handle handle, u32 Level, void *context, void **retval) 1390 { 1391 acpi_status status; 1392 unsigned long long tmp = 0; 1393 struct acpi_ec *ec = context; 1394 1395 /* clear addr values, ec_parse_io_ports depend on it */ 1396 ec->command_addr = ec->data_addr = 0; 1397 1398 status = acpi_walk_resources(handle, METHOD_NAME__CRS, 1399 ec_parse_io_ports, ec); 1400 if (ACPI_FAILURE(status)) 1401 return status; 1402 if (ec->data_addr == 0 || ec->command_addr == 0) 1403 return AE_OK; 1404 1405 /* Get GPE bit assignment (EC events). */ 1406 /* TODO: Add support for _GPE returning a package */ 1407 status = acpi_evaluate_integer(handle, "_GPE", NULL, &tmp); 1408 if (ACPI_SUCCESS(status)) 1409 ec->gpe = tmp; 1410 /* 1411 * Errors are non-fatal, allowing for ACPI Reduced Hardware 1412 * platforms which use GpioInt instead of GPE. 1413 */ 1414 1415 /* Use the global lock for all EC transactions? */ 1416 tmp = 0; 1417 acpi_evaluate_integer(handle, "_GLK", NULL, &tmp); 1418 ec->global_lock = tmp; 1419 ec->handle = handle; 1420 return AE_CTRL_TERMINATE; 1421 } 1422 1423 static bool install_gpe_event_handler(struct acpi_ec *ec) 1424 { 1425 acpi_status status; 1426 1427 status = acpi_install_gpe_raw_handler(NULL, ec->gpe, 1428 ACPI_GPE_EDGE_TRIGGERED, 1429 &acpi_ec_gpe_handler, ec); 1430 if (ACPI_FAILURE(status)) 1431 return false; 1432 1433 if (test_bit(EC_FLAGS_STARTED, &ec->flags) && ec->reference_count >= 1) 1434 acpi_ec_enable_gpe(ec, true); 1435 1436 return true; 1437 } 1438 1439 static bool install_gpio_irq_event_handler(struct acpi_ec *ec) 1440 { 1441 return request_threaded_irq(ec->irq, NULL, acpi_ec_irq_handler, 1442 IRQF_SHARED | IRQF_ONESHOT, "ACPI EC", ec) >= 0; 1443 } 1444 1445 /** 1446 * ec_install_handlers - Install service callbacks and register query methods. 1447 * @ec: Target EC. 1448 * @device: ACPI device object corresponding to @ec. 1449 * @call_reg: If _REG should be called to notify OpRegion availability 1450 * 1451 * Install a handler for the EC address space type unless it has been installed 1452 * already. If @device is not NULL, also look for EC query methods in the 1453 * namespace and register them, and install an event (either GPE or GPIO IRQ) 1454 * handler for the EC, if possible. 1455 * 1456 * Return: 1457 * -ENODEV if the address space handler cannot be installed, which means 1458 * "unable to handle transactions", 1459 * -EPROBE_DEFER if GPIO IRQ acquisition needs to be deferred, 1460 * or 0 (success) otherwise. 1461 */ 1462 static int ec_install_handlers(struct acpi_ec *ec, struct acpi_device *device, 1463 bool call_reg) 1464 { 1465 acpi_status status; 1466 1467 acpi_ec_start(ec, false); 1468 1469 if (!test_bit(EC_FLAGS_EC_HANDLER_INSTALLED, &ec->flags)) { 1470 acpi_ec_enter_noirq(ec); 1471 status = acpi_install_address_space_handler_no_reg(ec->handle, 1472 ACPI_ADR_SPACE_EC, 1473 &acpi_ec_space_handler, 1474 NULL, ec); 1475 if (ACPI_FAILURE(status)) { 1476 acpi_ec_stop(ec, false); 1477 return -ENODEV; 1478 } 1479 set_bit(EC_FLAGS_EC_HANDLER_INSTALLED, &ec->flags); 1480 ec->address_space_handler_holder = ec->handle; 1481 } 1482 1483 if (call_reg && !test_bit(EC_FLAGS_EC_REG_CALLED, &ec->flags)) { 1484 acpi_execute_reg_methods(ec->handle, ACPI_ADR_SPACE_EC); 1485 set_bit(EC_FLAGS_EC_REG_CALLED, &ec->flags); 1486 } 1487 1488 if (!device) 1489 return 0; 1490 1491 if (ec->gpe < 0) { 1492 /* ACPI reduced hardware platforms use a GpioInt from _CRS. */ 1493 int irq = acpi_dev_gpio_irq_get(device, 0); 1494 /* 1495 * Bail out right away for deferred probing or complete the 1496 * initialization regardless of any other errors. 1497 */ 1498 if (irq == -EPROBE_DEFER) 1499 return -EPROBE_DEFER; 1500 else if (irq >= 0) 1501 ec->irq = irq; 1502 } 1503 1504 if (!test_bit(EC_FLAGS_QUERY_METHODS_INSTALLED, &ec->flags)) { 1505 /* Find and register all query methods */ 1506 acpi_walk_namespace(ACPI_TYPE_METHOD, ec->handle, 1, 1507 acpi_ec_register_query_methods, 1508 NULL, ec, NULL); 1509 set_bit(EC_FLAGS_QUERY_METHODS_INSTALLED, &ec->flags); 1510 } 1511 if (!test_bit(EC_FLAGS_EVENT_HANDLER_INSTALLED, &ec->flags)) { 1512 bool ready = false; 1513 1514 if (ec->gpe >= 0) 1515 ready = install_gpe_event_handler(ec); 1516 else if (ec->irq >= 0) 1517 ready = install_gpio_irq_event_handler(ec); 1518 1519 if (ready) { 1520 set_bit(EC_FLAGS_EVENT_HANDLER_INSTALLED, &ec->flags); 1521 acpi_ec_leave_noirq(ec); 1522 } 1523 /* 1524 * Failures to install an event handler are not fatal, because 1525 * the EC can be polled for events. 1526 */ 1527 } 1528 /* EC is fully operational, allow queries */ 1529 acpi_ec_enable_event(ec); 1530 1531 return 0; 1532 } 1533 1534 static void ec_remove_handlers(struct acpi_ec *ec) 1535 { 1536 if (test_bit(EC_FLAGS_EC_HANDLER_INSTALLED, &ec->flags)) { 1537 if (ACPI_FAILURE(acpi_remove_address_space_handler( 1538 ec->address_space_handler_holder, 1539 ACPI_ADR_SPACE_EC, &acpi_ec_space_handler))) 1540 pr_err("failed to remove space handler\n"); 1541 clear_bit(EC_FLAGS_EC_HANDLER_INSTALLED, &ec->flags); 1542 } 1543 1544 /* 1545 * Stops handling the EC transactions after removing the operation 1546 * region handler. This is required because _REG(DISCONNECT) 1547 * invoked during the removal can result in new EC transactions. 1548 * 1549 * Flushes the EC requests and thus disables the GPE before 1550 * removing the GPE handler. This is required by the current ACPICA 1551 * GPE core. ACPICA GPE core will automatically disable a GPE when 1552 * it is indicated but there is no way to handle it. So the drivers 1553 * must disable the GPEs prior to removing the GPE handlers. 1554 */ 1555 acpi_ec_stop(ec, false); 1556 1557 if (test_bit(EC_FLAGS_EVENT_HANDLER_INSTALLED, &ec->flags)) { 1558 if (ec->gpe >= 0 && 1559 ACPI_FAILURE(acpi_remove_gpe_handler(NULL, ec->gpe, 1560 &acpi_ec_gpe_handler))) 1561 pr_err("failed to remove gpe handler\n"); 1562 1563 if (ec->irq >= 0) 1564 free_irq(ec->irq, ec); 1565 1566 clear_bit(EC_FLAGS_EVENT_HANDLER_INSTALLED, &ec->flags); 1567 } 1568 if (test_bit(EC_FLAGS_QUERY_METHODS_INSTALLED, &ec->flags)) { 1569 acpi_ec_remove_query_handlers(ec, true, 0); 1570 clear_bit(EC_FLAGS_QUERY_METHODS_INSTALLED, &ec->flags); 1571 } 1572 } 1573 1574 static int acpi_ec_setup(struct acpi_ec *ec, struct acpi_device *device, bool call_reg) 1575 { 1576 int ret; 1577 1578 ret = ec_install_handlers(ec, device, call_reg); 1579 if (ret) 1580 return ret; 1581 1582 /* First EC capable of handling transactions */ 1583 if (!first_ec) 1584 first_ec = ec; 1585 1586 pr_info("EC_CMD/EC_SC=0x%lx, EC_DATA=0x%lx\n", ec->command_addr, 1587 ec->data_addr); 1588 1589 if (test_bit(EC_FLAGS_EVENT_HANDLER_INSTALLED, &ec->flags)) { 1590 if (ec->gpe >= 0) 1591 pr_info("GPE=0x%x\n", ec->gpe); 1592 else 1593 pr_info("IRQ=%d\n", ec->irq); 1594 } 1595 1596 return ret; 1597 } 1598 1599 static int acpi_ec_add(struct acpi_device *device) 1600 { 1601 struct acpi_ec *ec; 1602 int ret; 1603 1604 strcpy(acpi_device_name(device), ACPI_EC_DEVICE_NAME); 1605 strcpy(acpi_device_class(device), ACPI_EC_CLASS); 1606 1607 if (boot_ec && (boot_ec->handle == device->handle || 1608 !strcmp(acpi_device_hid(device), ACPI_ECDT_HID))) { 1609 /* Fast path: this device corresponds to the boot EC. */ 1610 ec = boot_ec; 1611 } else { 1612 acpi_status status; 1613 1614 ec = acpi_ec_alloc(); 1615 if (!ec) 1616 return -ENOMEM; 1617 1618 status = ec_parse_device(device->handle, 0, ec, NULL); 1619 if (status != AE_CTRL_TERMINATE) { 1620 ret = -EINVAL; 1621 goto err; 1622 } 1623 1624 if (boot_ec && ec->command_addr == boot_ec->command_addr && 1625 ec->data_addr == boot_ec->data_addr) { 1626 /* 1627 * Trust PNP0C09 namespace location rather than ECDT ID. 1628 * But trust ECDT GPE rather than _GPE because of ASUS 1629 * quirks. So do not change boot_ec->gpe to ec->gpe, 1630 * except when the TRUST_DSDT_GPE quirk is set. 1631 */ 1632 boot_ec->handle = ec->handle; 1633 1634 if (EC_FLAGS_TRUST_DSDT_GPE) 1635 boot_ec->gpe = ec->gpe; 1636 1637 acpi_handle_debug(ec->handle, "duplicated.\n"); 1638 acpi_ec_free(ec); 1639 ec = boot_ec; 1640 } 1641 } 1642 1643 ret = acpi_ec_setup(ec, device, true); 1644 if (ret) 1645 goto err; 1646 1647 if (ec == boot_ec) 1648 acpi_handle_info(boot_ec->handle, 1649 "Boot %s EC initialization complete\n", 1650 boot_ec_is_ecdt ? "ECDT" : "DSDT"); 1651 1652 acpi_handle_info(ec->handle, 1653 "EC: Used to handle transactions and events\n"); 1654 1655 device->driver_data = ec; 1656 1657 ret = !!request_region(ec->data_addr, 1, "EC data"); 1658 WARN(!ret, "Could not request EC data io port 0x%lx", ec->data_addr); 1659 ret = !!request_region(ec->command_addr, 1, "EC cmd"); 1660 WARN(!ret, "Could not request EC cmd io port 0x%lx", ec->command_addr); 1661 1662 /* Reprobe devices depending on the EC */ 1663 acpi_dev_clear_dependencies(device); 1664 1665 acpi_handle_debug(ec->handle, "enumerated.\n"); 1666 return 0; 1667 1668 err: 1669 if (ec != boot_ec) 1670 acpi_ec_free(ec); 1671 1672 return ret; 1673 } 1674 1675 static void acpi_ec_remove(struct acpi_device *device) 1676 { 1677 struct acpi_ec *ec; 1678 1679 if (!device) 1680 return; 1681 1682 ec = acpi_driver_data(device); 1683 release_region(ec->data_addr, 1); 1684 release_region(ec->command_addr, 1); 1685 device->driver_data = NULL; 1686 if (ec != boot_ec) { 1687 ec_remove_handlers(ec); 1688 acpi_ec_free(ec); 1689 } 1690 } 1691 1692 static acpi_status 1693 ec_parse_io_ports(struct acpi_resource *resource, void *context) 1694 { 1695 struct acpi_ec *ec = context; 1696 1697 if (resource->type != ACPI_RESOURCE_TYPE_IO) 1698 return AE_OK; 1699 1700 /* 1701 * The first address region returned is the data port, and 1702 * the second address region returned is the status/command 1703 * port. 1704 */ 1705 if (ec->data_addr == 0) 1706 ec->data_addr = resource->data.io.minimum; 1707 else if (ec->command_addr == 0) 1708 ec->command_addr = resource->data.io.minimum; 1709 else 1710 return AE_CTRL_TERMINATE; 1711 1712 return AE_OK; 1713 } 1714 1715 static const struct acpi_device_id ec_device_ids[] = { 1716 {"PNP0C09", 0}, 1717 {ACPI_ECDT_HID, 0}, 1718 {"", 0}, 1719 }; 1720 1721 /* 1722 * This function is not Windows-compatible as Windows never enumerates the 1723 * namespace EC before the main ACPI device enumeration process. It is 1724 * retained for historical reason and will be deprecated in the future. 1725 */ 1726 void __init acpi_ec_dsdt_probe(void) 1727 { 1728 struct acpi_ec *ec; 1729 acpi_status status; 1730 int ret; 1731 1732 /* 1733 * If a platform has ECDT, there is no need to proceed as the 1734 * following probe is not a part of the ACPI device enumeration, 1735 * executing _STA is not safe, and thus this probe may risk of 1736 * picking up an invalid EC device. 1737 */ 1738 if (boot_ec) 1739 return; 1740 1741 ec = acpi_ec_alloc(); 1742 if (!ec) 1743 return; 1744 1745 /* 1746 * At this point, the namespace is initialized, so start to find 1747 * the namespace objects. 1748 */ 1749 status = acpi_get_devices(ec_device_ids[0].id, ec_parse_device, ec, NULL); 1750 if (ACPI_FAILURE(status) || !ec->handle) { 1751 acpi_ec_free(ec); 1752 return; 1753 } 1754 1755 /* 1756 * When the DSDT EC is available, always re-configure boot EC to 1757 * have _REG evaluated. _REG can only be evaluated after the 1758 * namespace initialization. 1759 * At this point, the GPE is not fully initialized, so do not to 1760 * handle the events. 1761 */ 1762 ret = acpi_ec_setup(ec, NULL, true); 1763 if (ret) { 1764 acpi_ec_free(ec); 1765 return; 1766 } 1767 1768 boot_ec = ec; 1769 1770 acpi_handle_info(ec->handle, 1771 "Boot DSDT EC used to handle transactions\n"); 1772 } 1773 1774 /* 1775 * acpi_ec_ecdt_start - Finalize the boot ECDT EC initialization. 1776 * 1777 * First, look for an ACPI handle for the boot ECDT EC if acpi_ec_add() has not 1778 * found a matching object in the namespace. 1779 * 1780 * Next, in case the DSDT EC is not functioning, it is still necessary to 1781 * provide a functional ECDT EC to handle events, so add an extra device object 1782 * to represent it (see https://bugzilla.kernel.org/show_bug.cgi?id=115021). 1783 * 1784 * This is useful on platforms with valid ECDT and invalid DSDT EC settings, 1785 * like ASUS X550ZE (see https://bugzilla.kernel.org/show_bug.cgi?id=196847). 1786 */ 1787 static void __init acpi_ec_ecdt_start(void) 1788 { 1789 struct acpi_table_ecdt *ecdt_ptr; 1790 acpi_handle handle; 1791 acpi_status status; 1792 1793 /* Bail out if a matching EC has been found in the namespace. */ 1794 if (!boot_ec || boot_ec->handle != ACPI_ROOT_OBJECT) 1795 return; 1796 1797 /* Look up the object pointed to from the ECDT in the namespace. */ 1798 status = acpi_get_table(ACPI_SIG_ECDT, 1, 1799 (struct acpi_table_header **)&ecdt_ptr); 1800 if (ACPI_FAILURE(status)) 1801 return; 1802 1803 status = acpi_get_handle(NULL, ecdt_ptr->id, &handle); 1804 if (ACPI_SUCCESS(status)) { 1805 boot_ec->handle = handle; 1806 1807 /* Add a special ACPI device object to represent the boot EC. */ 1808 acpi_bus_register_early_device(ACPI_BUS_TYPE_ECDT_EC); 1809 } 1810 1811 acpi_put_table((struct acpi_table_header *)ecdt_ptr); 1812 } 1813 1814 /* 1815 * On some hardware it is necessary to clear events accumulated by the EC during 1816 * sleep. These ECs stop reporting GPEs until they are manually polled, if too 1817 * many events are accumulated. (e.g. Samsung Series 5/9 notebooks) 1818 * 1819 * https://bugzilla.kernel.org/show_bug.cgi?id=44161 1820 * 1821 * Ideally, the EC should also be instructed NOT to accumulate events during 1822 * sleep (which Windows seems to do somehow), but the interface to control this 1823 * behaviour is not known at this time. 1824 * 1825 * Models known to be affected are Samsung 530Uxx/535Uxx/540Uxx/550Pxx/900Xxx, 1826 * however it is very likely that other Samsung models are affected. 1827 * 1828 * On systems which don't accumulate _Q events during sleep, this extra check 1829 * should be harmless. 1830 */ 1831 static int ec_clear_on_resume(const struct dmi_system_id *id) 1832 { 1833 pr_debug("Detected system needing EC poll on resume.\n"); 1834 EC_FLAGS_CLEAR_ON_RESUME = 1; 1835 ec_event_clearing = ACPI_EC_EVT_TIMING_STATUS; 1836 return 0; 1837 } 1838 1839 /* 1840 * Some ECDTs contain wrong register addresses. 1841 * MSI MS-171F 1842 * https://bugzilla.kernel.org/show_bug.cgi?id=12461 1843 */ 1844 static int ec_correct_ecdt(const struct dmi_system_id *id) 1845 { 1846 pr_debug("Detected system needing ECDT address correction.\n"); 1847 EC_FLAGS_CORRECT_ECDT = 1; 1848 return 0; 1849 } 1850 1851 /* 1852 * Some ECDTs contain wrong GPE setting, but they share the same port addresses 1853 * with DSDT EC, don't duplicate the DSDT EC with ECDT EC in this case. 1854 * https://bugzilla.kernel.org/show_bug.cgi?id=209989 1855 */ 1856 static int ec_honor_dsdt_gpe(const struct dmi_system_id *id) 1857 { 1858 pr_debug("Detected system needing DSDT GPE setting.\n"); 1859 EC_FLAGS_TRUST_DSDT_GPE = 1; 1860 return 0; 1861 } 1862 1863 static const struct dmi_system_id ec_dmi_table[] __initconst = { 1864 { 1865 /* 1866 * MSI MS-171F 1867 * https://bugzilla.kernel.org/show_bug.cgi?id=12461 1868 */ 1869 .callback = ec_correct_ecdt, 1870 .matches = { 1871 DMI_MATCH(DMI_SYS_VENDOR, "Micro-Star"), 1872 DMI_MATCH(DMI_PRODUCT_NAME, "MS-171F"), 1873 }, 1874 }, 1875 { 1876 /* 1877 * HP Pavilion Gaming Laptop 15-cx0xxx 1878 * https://bugzilla.kernel.org/show_bug.cgi?id=209989 1879 */ 1880 .callback = ec_honor_dsdt_gpe, 1881 .matches = { 1882 DMI_MATCH(DMI_SYS_VENDOR, "HP"), 1883 DMI_MATCH(DMI_PRODUCT_NAME, "HP Pavilion Gaming Laptop 15-cx0xxx"), 1884 }, 1885 }, 1886 { 1887 /* 1888 * HP Pavilion Gaming Laptop 15-cx0041ur 1889 */ 1890 .callback = ec_honor_dsdt_gpe, 1891 .matches = { 1892 DMI_MATCH(DMI_SYS_VENDOR, "HP"), 1893 DMI_MATCH(DMI_PRODUCT_NAME, "HP 15-cx0041ur"), 1894 }, 1895 }, 1896 { 1897 /* 1898 * HP Pavilion Gaming Laptop 15-dk1xxx 1899 * https://github.com/systemd/systemd/issues/28942 1900 */ 1901 .callback = ec_honor_dsdt_gpe, 1902 .matches = { 1903 DMI_MATCH(DMI_SYS_VENDOR, "HP"), 1904 DMI_MATCH(DMI_PRODUCT_NAME, "HP Pavilion Gaming Laptop 15-dk1xxx"), 1905 }, 1906 }, 1907 { 1908 /* 1909 * HP 250 G7 Notebook PC 1910 */ 1911 .callback = ec_honor_dsdt_gpe, 1912 .matches = { 1913 DMI_MATCH(DMI_SYS_VENDOR, "HP"), 1914 DMI_MATCH(DMI_PRODUCT_NAME, "HP 250 G7 Notebook PC"), 1915 }, 1916 }, 1917 { 1918 /* 1919 * Samsung hardware 1920 * https://bugzilla.kernel.org/show_bug.cgi?id=44161 1921 */ 1922 .callback = ec_clear_on_resume, 1923 .matches = { 1924 DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."), 1925 }, 1926 }, 1927 {} 1928 }; 1929 1930 void __init acpi_ec_ecdt_probe(void) 1931 { 1932 struct acpi_table_ecdt *ecdt_ptr; 1933 struct acpi_ec *ec; 1934 acpi_status status; 1935 int ret; 1936 1937 /* Generate a boot ec context. */ 1938 dmi_check_system(ec_dmi_table); 1939 status = acpi_get_table(ACPI_SIG_ECDT, 1, 1940 (struct acpi_table_header **)&ecdt_ptr); 1941 if (ACPI_FAILURE(status)) 1942 return; 1943 1944 if (!ecdt_ptr->control.address || !ecdt_ptr->data.address) { 1945 /* 1946 * Asus X50GL: 1947 * https://bugzilla.kernel.org/show_bug.cgi?id=11880 1948 */ 1949 goto out; 1950 } 1951 1952 ec = acpi_ec_alloc(); 1953 if (!ec) 1954 goto out; 1955 1956 if (EC_FLAGS_CORRECT_ECDT) { 1957 ec->command_addr = ecdt_ptr->data.address; 1958 ec->data_addr = ecdt_ptr->control.address; 1959 } else { 1960 ec->command_addr = ecdt_ptr->control.address; 1961 ec->data_addr = ecdt_ptr->data.address; 1962 } 1963 1964 /* 1965 * Ignore the GPE value on Reduced Hardware platforms. 1966 * Some products have this set to an erroneous value. 1967 */ 1968 if (!acpi_gbl_reduced_hardware) 1969 ec->gpe = ecdt_ptr->gpe; 1970 1971 ec->handle = ACPI_ROOT_OBJECT; 1972 1973 /* 1974 * At this point, the namespace is not initialized, so do not find 1975 * the namespace objects, or handle the events. 1976 */ 1977 ret = acpi_ec_setup(ec, NULL, false); 1978 if (ret) { 1979 acpi_ec_free(ec); 1980 goto out; 1981 } 1982 1983 boot_ec = ec; 1984 boot_ec_is_ecdt = true; 1985 1986 pr_info("Boot ECDT EC used to handle transactions\n"); 1987 1988 out: 1989 acpi_put_table((struct acpi_table_header *)ecdt_ptr); 1990 } 1991 1992 #ifdef CONFIG_PM_SLEEP 1993 static int acpi_ec_suspend(struct device *dev) 1994 { 1995 struct acpi_ec *ec = 1996 acpi_driver_data(to_acpi_device(dev)); 1997 1998 if (!pm_suspend_no_platform() && ec_freeze_events) 1999 acpi_ec_disable_event(ec); 2000 return 0; 2001 } 2002 2003 static int acpi_ec_suspend_noirq(struct device *dev) 2004 { 2005 struct acpi_ec *ec = acpi_driver_data(to_acpi_device(dev)); 2006 2007 /* 2008 * The SCI handler doesn't run at this point, so the GPE can be 2009 * masked at the low level without side effects. 2010 */ 2011 if (ec_no_wakeup && test_bit(EC_FLAGS_STARTED, &ec->flags) && 2012 ec->gpe >= 0 && ec->reference_count >= 1) 2013 acpi_set_gpe(NULL, ec->gpe, ACPI_GPE_DISABLE); 2014 2015 acpi_ec_enter_noirq(ec); 2016 2017 return 0; 2018 } 2019 2020 static int acpi_ec_resume_noirq(struct device *dev) 2021 { 2022 struct acpi_ec *ec = acpi_driver_data(to_acpi_device(dev)); 2023 2024 acpi_ec_leave_noirq(ec); 2025 2026 if (ec_no_wakeup && test_bit(EC_FLAGS_STARTED, &ec->flags) && 2027 ec->gpe >= 0 && ec->reference_count >= 1) 2028 acpi_set_gpe(NULL, ec->gpe, ACPI_GPE_ENABLE); 2029 2030 return 0; 2031 } 2032 2033 static int acpi_ec_resume(struct device *dev) 2034 { 2035 struct acpi_ec *ec = 2036 acpi_driver_data(to_acpi_device(dev)); 2037 2038 acpi_ec_enable_event(ec); 2039 return 0; 2040 } 2041 2042 void acpi_ec_mark_gpe_for_wake(void) 2043 { 2044 if (first_ec && !ec_no_wakeup) 2045 acpi_mark_gpe_for_wake(NULL, first_ec->gpe); 2046 } 2047 EXPORT_SYMBOL_GPL(acpi_ec_mark_gpe_for_wake); 2048 2049 void acpi_ec_set_gpe_wake_mask(u8 action) 2050 { 2051 if (pm_suspend_no_platform() && first_ec && !ec_no_wakeup) 2052 acpi_set_gpe_wake_mask(NULL, first_ec->gpe, action); 2053 } 2054 2055 static bool acpi_ec_work_in_progress(struct acpi_ec *ec) 2056 { 2057 return ec->events_in_progress + ec->queries_in_progress > 0; 2058 } 2059 2060 bool acpi_ec_dispatch_gpe(void) 2061 { 2062 bool work_in_progress = false; 2063 2064 if (!first_ec) 2065 return acpi_any_gpe_status_set(U32_MAX); 2066 2067 /* 2068 * Report wakeup if the status bit is set for any enabled GPE other 2069 * than the EC one. 2070 */ 2071 if (acpi_any_gpe_status_set(first_ec->gpe)) 2072 return true; 2073 2074 /* 2075 * Cancel the SCI wakeup and process all pending events in case there 2076 * are any wakeup ones in there. 2077 * 2078 * Note that if any non-EC GPEs are active at this point, the SCI will 2079 * retrigger after the rearming in acpi_s2idle_wake(), so no events 2080 * should be missed by canceling the wakeup here. 2081 */ 2082 pm_system_cancel_wakeup(); 2083 2084 /* 2085 * Dispatch the EC GPE in-band, but do not report wakeup in any case 2086 * to allow the caller to process events properly after that. 2087 */ 2088 spin_lock(&first_ec->lock); 2089 2090 if (acpi_ec_gpe_status_set(first_ec)) { 2091 pm_pr_dbg("ACPI EC GPE status set\n"); 2092 2093 clear_gpe_and_advance_transaction(first_ec, false); 2094 work_in_progress = acpi_ec_work_in_progress(first_ec); 2095 } 2096 2097 spin_unlock(&first_ec->lock); 2098 2099 if (!work_in_progress) 2100 return false; 2101 2102 pm_pr_dbg("ACPI EC GPE dispatched\n"); 2103 2104 /* Drain EC work. */ 2105 do { 2106 acpi_ec_flush_work(); 2107 2108 pm_pr_dbg("ACPI EC work flushed\n"); 2109 2110 spin_lock(&first_ec->lock); 2111 2112 work_in_progress = acpi_ec_work_in_progress(first_ec); 2113 2114 spin_unlock(&first_ec->lock); 2115 } while (work_in_progress && !pm_wakeup_pending()); 2116 2117 return false; 2118 } 2119 #endif /* CONFIG_PM_SLEEP */ 2120 2121 static const struct dev_pm_ops acpi_ec_pm = { 2122 SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(acpi_ec_suspend_noirq, acpi_ec_resume_noirq) 2123 SET_SYSTEM_SLEEP_PM_OPS(acpi_ec_suspend, acpi_ec_resume) 2124 }; 2125 2126 static int param_set_event_clearing(const char *val, 2127 const struct kernel_param *kp) 2128 { 2129 int result = 0; 2130 2131 if (!strncmp(val, "status", sizeof("status") - 1)) { 2132 ec_event_clearing = ACPI_EC_EVT_TIMING_STATUS; 2133 pr_info("Assuming SCI_EVT clearing on EC_SC accesses\n"); 2134 } else if (!strncmp(val, "query", sizeof("query") - 1)) { 2135 ec_event_clearing = ACPI_EC_EVT_TIMING_QUERY; 2136 pr_info("Assuming SCI_EVT clearing on QR_EC writes\n"); 2137 } else if (!strncmp(val, "event", sizeof("event") - 1)) { 2138 ec_event_clearing = ACPI_EC_EVT_TIMING_EVENT; 2139 pr_info("Assuming SCI_EVT clearing on event reads\n"); 2140 } else 2141 result = -EINVAL; 2142 return result; 2143 } 2144 2145 static int param_get_event_clearing(char *buffer, 2146 const struct kernel_param *kp) 2147 { 2148 switch (ec_event_clearing) { 2149 case ACPI_EC_EVT_TIMING_STATUS: 2150 return sprintf(buffer, "status\n"); 2151 case ACPI_EC_EVT_TIMING_QUERY: 2152 return sprintf(buffer, "query\n"); 2153 case ACPI_EC_EVT_TIMING_EVENT: 2154 return sprintf(buffer, "event\n"); 2155 default: 2156 return sprintf(buffer, "invalid\n"); 2157 } 2158 return 0; 2159 } 2160 2161 module_param_call(ec_event_clearing, param_set_event_clearing, param_get_event_clearing, 2162 NULL, 0644); 2163 MODULE_PARM_DESC(ec_event_clearing, "Assumed SCI_EVT clearing timing"); 2164 2165 static struct acpi_driver acpi_ec_driver = { 2166 .name = "ec", 2167 .class = ACPI_EC_CLASS, 2168 .ids = ec_device_ids, 2169 .ops = { 2170 .add = acpi_ec_add, 2171 .remove = acpi_ec_remove, 2172 }, 2173 .drv.pm = &acpi_ec_pm, 2174 }; 2175 2176 static void acpi_ec_destroy_workqueues(void) 2177 { 2178 if (ec_wq) { 2179 destroy_workqueue(ec_wq); 2180 ec_wq = NULL; 2181 } 2182 if (ec_query_wq) { 2183 destroy_workqueue(ec_query_wq); 2184 ec_query_wq = NULL; 2185 } 2186 } 2187 2188 static int acpi_ec_init_workqueues(void) 2189 { 2190 if (!ec_wq) 2191 ec_wq = alloc_ordered_workqueue("kec", 0); 2192 2193 if (!ec_query_wq) 2194 ec_query_wq = alloc_workqueue("kec_query", 0, ec_max_queries); 2195 2196 if (!ec_wq || !ec_query_wq) { 2197 acpi_ec_destroy_workqueues(); 2198 return -ENODEV; 2199 } 2200 return 0; 2201 } 2202 2203 static const struct dmi_system_id acpi_ec_no_wakeup[] = { 2204 { 2205 .matches = { 2206 DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"), 2207 DMI_MATCH(DMI_PRODUCT_FAMILY, "Thinkpad X1 Carbon 6th"), 2208 }, 2209 }, 2210 { 2211 .matches = { 2212 DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"), 2213 DMI_MATCH(DMI_PRODUCT_FAMILY, "ThinkPad X1 Yoga 3rd"), 2214 }, 2215 }, 2216 { 2217 .matches = { 2218 DMI_MATCH(DMI_SYS_VENDOR, "HP"), 2219 DMI_MATCH(DMI_PRODUCT_FAMILY, "103C_5336AN HP ZHAN 66 Pro"), 2220 }, 2221 }, 2222 { }, 2223 }; 2224 2225 void __init acpi_ec_init(void) 2226 { 2227 int result; 2228 2229 result = acpi_ec_init_workqueues(); 2230 if (result) 2231 return; 2232 2233 /* 2234 * Disable EC wakeup on following systems to prevent periodic 2235 * wakeup from EC GPE. 2236 */ 2237 if (dmi_check_system(acpi_ec_no_wakeup)) { 2238 ec_no_wakeup = true; 2239 pr_debug("Disabling EC wakeup on suspend-to-idle\n"); 2240 } 2241 2242 /* Driver must be registered after acpi_ec_init_workqueues(). */ 2243 acpi_bus_register_driver(&acpi_ec_driver); 2244 2245 acpi_ec_ecdt_start(); 2246 } 2247 2248 /* EC driver currently not unloadable */ 2249 #if 0 2250 static void __exit acpi_ec_exit(void) 2251 { 2252 2253 acpi_bus_unregister_driver(&acpi_ec_driver); 2254 acpi_ec_destroy_workqueues(); 2255 } 2256 #endif /* 0 */ 2257