1 /* 2 * ec.c - ACPI Embedded Controller Driver (v3) 3 * 4 * Copyright (C) 2001-2015 Intel Corporation 5 * Author: 2014, 2015 Lv Zheng <lv.zheng@intel.com> 6 * 2006, 2007 Alexey Starikovskiy <alexey.y.starikovskiy@intel.com> 7 * 2006 Denis Sadykov <denis.m.sadykov@intel.com> 8 * 2004 Luming Yu <luming.yu@intel.com> 9 * 2001, 2002 Andy Grover <andrew.grover@intel.com> 10 * 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com> 11 * Copyright (C) 2008 Alexey Starikovskiy <astarikovskiy@suse.de> 12 * 13 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 14 * 15 * This program is free software; you can redistribute it and/or modify 16 * it under the terms of the GNU General Public License as published by 17 * the Free Software Foundation; either version 2 of the License, or (at 18 * your option) any later version. 19 * 20 * This program is distributed in the hope that it will be useful, but 21 * WITHOUT ANY WARRANTY; without even the implied warranty of 22 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 23 * General Public License for more details. 24 * 25 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 26 */ 27 28 /* Uncomment next line to get verbose printout */ 29 /* #define DEBUG */ 30 #define pr_fmt(fmt) "ACPI : EC: " fmt 31 32 #include <linux/kernel.h> 33 #include <linux/module.h> 34 #include <linux/init.h> 35 #include <linux/types.h> 36 #include <linux/delay.h> 37 #include <linux/interrupt.h> 38 #include <linux/list.h> 39 #include <linux/spinlock.h> 40 #include <linux/slab.h> 41 #include <linux/acpi.h> 42 #include <linux/dmi.h> 43 #include <asm/io.h> 44 45 #include "internal.h" 46 47 #define ACPI_EC_CLASS "embedded_controller" 48 #define ACPI_EC_DEVICE_NAME "Embedded Controller" 49 #define ACPI_EC_FILE_INFO "info" 50 51 /* EC status register */ 52 #define ACPI_EC_FLAG_OBF 0x01 /* Output buffer full */ 53 #define ACPI_EC_FLAG_IBF 0x02 /* Input buffer full */ 54 #define ACPI_EC_FLAG_CMD 0x08 /* Input buffer contains a command */ 55 #define ACPI_EC_FLAG_BURST 0x10 /* burst mode */ 56 #define ACPI_EC_FLAG_SCI 0x20 /* EC-SCI occurred */ 57 58 /* 59 * The SCI_EVT clearing timing is not defined by the ACPI specification. 60 * This leads to lots of practical timing issues for the host EC driver. 61 * The following variations are defined (from the target EC firmware's 62 * perspective): 63 * STATUS: After indicating SCI_EVT edge triggered IRQ to the host, the 64 * target can clear SCI_EVT at any time so long as the host can see 65 * the indication by reading the status register (EC_SC). So the 66 * host should re-check SCI_EVT after the first time the SCI_EVT 67 * indication is seen, which is the same time the query request 68 * (QR_EC) is written to the command register (EC_CMD). SCI_EVT set 69 * at any later time could indicate another event. Normally such 70 * kind of EC firmware has implemented an event queue and will 71 * return 0x00 to indicate "no outstanding event". 72 * QUERY: After seeing the query request (QR_EC) written to the command 73 * register (EC_CMD) by the host and having prepared the responding 74 * event value in the data register (EC_DATA), the target can safely 75 * clear SCI_EVT because the target can confirm that the current 76 * event is being handled by the host. The host then should check 77 * SCI_EVT right after reading the event response from the data 78 * register (EC_DATA). 79 * EVENT: After seeing the event response read from the data register 80 * (EC_DATA) by the host, the target can clear SCI_EVT. As the 81 * target requires time to notice the change in the data register 82 * (EC_DATA), the host may be required to wait additional guarding 83 * time before checking the SCI_EVT again. Such guarding may not be 84 * necessary if the host is notified via another IRQ. 85 */ 86 #define ACPI_EC_EVT_TIMING_STATUS 0x00 87 #define ACPI_EC_EVT_TIMING_QUERY 0x01 88 #define ACPI_EC_EVT_TIMING_EVENT 0x02 89 90 /* EC commands */ 91 enum ec_command { 92 ACPI_EC_COMMAND_READ = 0x80, 93 ACPI_EC_COMMAND_WRITE = 0x81, 94 ACPI_EC_BURST_ENABLE = 0x82, 95 ACPI_EC_BURST_DISABLE = 0x83, 96 ACPI_EC_COMMAND_QUERY = 0x84, 97 }; 98 99 #define ACPI_EC_DELAY 500 /* Wait 500ms max. during EC ops */ 100 #define ACPI_EC_UDELAY_GLK 1000 /* Wait 1ms max. to get global lock */ 101 #define ACPI_EC_UDELAY_POLL 550 /* Wait 1ms for EC transaction polling */ 102 #define ACPI_EC_CLEAR_MAX 100 /* Maximum number of events to query 103 * when trying to clear the EC */ 104 105 enum { 106 EC_FLAGS_QUERY_PENDING, /* Query is pending */ 107 EC_FLAGS_QUERY_GUARDING, /* Guard for SCI_EVT check */ 108 EC_FLAGS_GPE_HANDLER_INSTALLED, /* GPE handler installed */ 109 EC_FLAGS_EC_HANDLER_INSTALLED, /* OpReg handler installed */ 110 EC_FLAGS_STARTED, /* Driver is started */ 111 EC_FLAGS_STOPPED, /* Driver is stopped */ 112 EC_FLAGS_COMMAND_STORM, /* GPE storms occurred to the 113 * current command processing */ 114 }; 115 116 #define ACPI_EC_COMMAND_POLL 0x01 /* Available for command byte */ 117 #define ACPI_EC_COMMAND_COMPLETE 0x02 /* Completed last byte */ 118 119 /* ec.c is compiled in acpi namespace so this shows up as acpi.ec_delay param */ 120 static unsigned int ec_delay __read_mostly = ACPI_EC_DELAY; 121 module_param(ec_delay, uint, 0644); 122 MODULE_PARM_DESC(ec_delay, "Timeout(ms) waited until an EC command completes"); 123 124 static bool ec_busy_polling __read_mostly; 125 module_param(ec_busy_polling, bool, 0644); 126 MODULE_PARM_DESC(ec_busy_polling, "Use busy polling to advance EC transaction"); 127 128 static unsigned int ec_polling_guard __read_mostly = ACPI_EC_UDELAY_POLL; 129 module_param(ec_polling_guard, uint, 0644); 130 MODULE_PARM_DESC(ec_polling_guard, "Guard time(us) between EC accesses in polling modes"); 131 132 static unsigned int ec_event_clearing __read_mostly = ACPI_EC_EVT_TIMING_QUERY; 133 134 /* 135 * If the number of false interrupts per one transaction exceeds 136 * this threshold, will think there is a GPE storm happened and 137 * will disable the GPE for normal transaction. 138 */ 139 static unsigned int ec_storm_threshold __read_mostly = 8; 140 module_param(ec_storm_threshold, uint, 0644); 141 MODULE_PARM_DESC(ec_storm_threshold, "Maxim false GPE numbers not considered as GPE storm"); 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 }; 169 170 static int acpi_ec_query(struct acpi_ec *ec, u8 *data); 171 static void advance_transaction(struct acpi_ec *ec); 172 static void acpi_ec_event_handler(struct work_struct *work); 173 static void acpi_ec_event_processor(struct work_struct *work); 174 175 struct acpi_ec *boot_ec, *first_ec; 176 EXPORT_SYMBOL(first_ec); 177 178 static int EC_FLAGS_CLEAR_ON_RESUME; /* Needs acpi_ec_clear() on boot/resume */ 179 static int EC_FLAGS_QUERY_HANDSHAKE; /* Needs QR_EC issued when SCI_EVT set */ 180 static int EC_FLAGS_CORRECT_ECDT; /* Needs ECDT port address correction */ 181 182 /* -------------------------------------------------------------------------- 183 * Logging/Debugging 184 * -------------------------------------------------------------------------- */ 185 186 /* 187 * Splitters used by the developers to track the boundary of the EC 188 * handling processes. 189 */ 190 #ifdef DEBUG 191 #define EC_DBG_SEP " " 192 #define EC_DBG_DRV "+++++" 193 #define EC_DBG_STM "=====" 194 #define EC_DBG_REQ "*****" 195 #define EC_DBG_EVT "#####" 196 #else 197 #define EC_DBG_SEP "" 198 #define EC_DBG_DRV 199 #define EC_DBG_STM 200 #define EC_DBG_REQ 201 #define EC_DBG_EVT 202 #endif 203 204 #define ec_log_raw(fmt, ...) \ 205 pr_info(fmt "\n", ##__VA_ARGS__) 206 #define ec_dbg_raw(fmt, ...) \ 207 pr_debug(fmt "\n", ##__VA_ARGS__) 208 #define ec_log(filter, fmt, ...) \ 209 ec_log_raw(filter EC_DBG_SEP fmt EC_DBG_SEP filter, ##__VA_ARGS__) 210 #define ec_dbg(filter, fmt, ...) \ 211 ec_dbg_raw(filter EC_DBG_SEP fmt EC_DBG_SEP filter, ##__VA_ARGS__) 212 213 #define ec_log_drv(fmt, ...) \ 214 ec_log(EC_DBG_DRV, fmt, ##__VA_ARGS__) 215 #define ec_dbg_drv(fmt, ...) \ 216 ec_dbg(EC_DBG_DRV, fmt, ##__VA_ARGS__) 217 #define ec_dbg_stm(fmt, ...) \ 218 ec_dbg(EC_DBG_STM, fmt, ##__VA_ARGS__) 219 #define ec_dbg_req(fmt, ...) \ 220 ec_dbg(EC_DBG_REQ, fmt, ##__VA_ARGS__) 221 #define ec_dbg_evt(fmt, ...) \ 222 ec_dbg(EC_DBG_EVT, fmt, ##__VA_ARGS__) 223 #define ec_dbg_ref(ec, fmt, ...) \ 224 ec_dbg_raw("%lu: " fmt, ec->reference_count, ## __VA_ARGS__) 225 226 /* -------------------------------------------------------------------------- 227 * Device Flags 228 * -------------------------------------------------------------------------- */ 229 230 static bool acpi_ec_started(struct acpi_ec *ec) 231 { 232 return test_bit(EC_FLAGS_STARTED, &ec->flags) && 233 !test_bit(EC_FLAGS_STOPPED, &ec->flags); 234 } 235 236 static bool acpi_ec_flushed(struct acpi_ec *ec) 237 { 238 return ec->reference_count == 1; 239 } 240 241 /* -------------------------------------------------------------------------- 242 * EC Registers 243 * -------------------------------------------------------------------------- */ 244 245 static inline u8 acpi_ec_read_status(struct acpi_ec *ec) 246 { 247 u8 x = inb(ec->command_addr); 248 249 ec_dbg_raw("EC_SC(R) = 0x%2.2x " 250 "SCI_EVT=%d BURST=%d CMD=%d IBF=%d OBF=%d", 251 x, 252 !!(x & ACPI_EC_FLAG_SCI), 253 !!(x & ACPI_EC_FLAG_BURST), 254 !!(x & ACPI_EC_FLAG_CMD), 255 !!(x & ACPI_EC_FLAG_IBF), 256 !!(x & ACPI_EC_FLAG_OBF)); 257 return x; 258 } 259 260 static inline u8 acpi_ec_read_data(struct acpi_ec *ec) 261 { 262 u8 x = inb(ec->data_addr); 263 264 ec->timestamp = jiffies; 265 ec_dbg_raw("EC_DATA(R) = 0x%2.2x", x); 266 return x; 267 } 268 269 static inline void acpi_ec_write_cmd(struct acpi_ec *ec, u8 command) 270 { 271 ec_dbg_raw("EC_SC(W) = 0x%2.2x", command); 272 outb(command, ec->command_addr); 273 ec->timestamp = jiffies; 274 } 275 276 static inline void acpi_ec_write_data(struct acpi_ec *ec, u8 data) 277 { 278 ec_dbg_raw("EC_DATA(W) = 0x%2.2x", data); 279 outb(data, ec->data_addr); 280 ec->timestamp = jiffies; 281 } 282 283 #ifdef DEBUG 284 static const char *acpi_ec_cmd_string(u8 cmd) 285 { 286 switch (cmd) { 287 case 0x80: 288 return "RD_EC"; 289 case 0x81: 290 return "WR_EC"; 291 case 0x82: 292 return "BE_EC"; 293 case 0x83: 294 return "BD_EC"; 295 case 0x84: 296 return "QR_EC"; 297 } 298 return "UNKNOWN"; 299 } 300 #else 301 #define acpi_ec_cmd_string(cmd) "UNDEF" 302 #endif 303 304 /* -------------------------------------------------------------------------- 305 * GPE Registers 306 * -------------------------------------------------------------------------- */ 307 308 static inline bool acpi_ec_is_gpe_raised(struct acpi_ec *ec) 309 { 310 acpi_event_status gpe_status = 0; 311 312 (void)acpi_get_gpe_status(NULL, ec->gpe, &gpe_status); 313 return (gpe_status & ACPI_EVENT_FLAG_STATUS_SET) ? true : false; 314 } 315 316 static inline void acpi_ec_enable_gpe(struct acpi_ec *ec, bool open) 317 { 318 if (open) 319 acpi_enable_gpe(NULL, ec->gpe); 320 else { 321 BUG_ON(ec->reference_count < 1); 322 acpi_set_gpe(NULL, ec->gpe, ACPI_GPE_ENABLE); 323 } 324 if (acpi_ec_is_gpe_raised(ec)) { 325 /* 326 * On some platforms, EN=1 writes cannot trigger GPE. So 327 * software need to manually trigger a pseudo GPE event on 328 * EN=1 writes. 329 */ 330 ec_dbg_raw("Polling quirk"); 331 advance_transaction(ec); 332 } 333 } 334 335 static inline void acpi_ec_disable_gpe(struct acpi_ec *ec, bool close) 336 { 337 if (close) 338 acpi_disable_gpe(NULL, ec->gpe); 339 else { 340 BUG_ON(ec->reference_count < 1); 341 acpi_set_gpe(NULL, ec->gpe, ACPI_GPE_DISABLE); 342 } 343 } 344 345 static inline void acpi_ec_clear_gpe(struct acpi_ec *ec) 346 { 347 /* 348 * GPE STS is a W1C register, which means: 349 * 1. Software can clear it without worrying about clearing other 350 * GPEs' STS bits when the hardware sets them in parallel. 351 * 2. As long as software can ensure only clearing it when it is 352 * set, hardware won't set it in parallel. 353 * So software can clear GPE in any contexts. 354 * Warning: do not move the check into advance_transaction() as the 355 * EC commands will be sent without GPE raised. 356 */ 357 if (!acpi_ec_is_gpe_raised(ec)) 358 return; 359 acpi_clear_gpe(NULL, ec->gpe); 360 } 361 362 /* -------------------------------------------------------------------------- 363 * Transaction Management 364 * -------------------------------------------------------------------------- */ 365 366 static void acpi_ec_submit_request(struct acpi_ec *ec) 367 { 368 ec->reference_count++; 369 if (test_bit(EC_FLAGS_GPE_HANDLER_INSTALLED, &ec->flags) && 370 ec->reference_count == 1) 371 acpi_ec_enable_gpe(ec, true); 372 } 373 374 static void acpi_ec_complete_request(struct acpi_ec *ec) 375 { 376 bool flushed = false; 377 378 ec->reference_count--; 379 if (test_bit(EC_FLAGS_GPE_HANDLER_INSTALLED, &ec->flags) && 380 ec->reference_count == 0) 381 acpi_ec_disable_gpe(ec, true); 382 flushed = acpi_ec_flushed(ec); 383 if (flushed) 384 wake_up(&ec->wait); 385 } 386 387 static void acpi_ec_set_storm(struct acpi_ec *ec, u8 flag) 388 { 389 if (!test_bit(flag, &ec->flags)) { 390 acpi_ec_disable_gpe(ec, false); 391 ec_dbg_drv("Polling enabled"); 392 set_bit(flag, &ec->flags); 393 } 394 } 395 396 static void acpi_ec_clear_storm(struct acpi_ec *ec, u8 flag) 397 { 398 if (test_bit(flag, &ec->flags)) { 399 clear_bit(flag, &ec->flags); 400 acpi_ec_enable_gpe(ec, false); 401 ec_dbg_drv("Polling disabled"); 402 } 403 } 404 405 /* 406 * acpi_ec_submit_flushable_request() - Increase the reference count unless 407 * the flush operation is not in 408 * progress 409 * @ec: the EC device 410 * 411 * This function must be used before taking a new action that should hold 412 * the reference count. If this function returns false, then the action 413 * must be discarded or it will prevent the flush operation from being 414 * completed. 415 */ 416 static bool acpi_ec_submit_flushable_request(struct acpi_ec *ec) 417 { 418 if (!acpi_ec_started(ec)) 419 return false; 420 acpi_ec_submit_request(ec); 421 return true; 422 } 423 424 static void acpi_ec_submit_query(struct acpi_ec *ec) 425 { 426 if (!test_and_set_bit(EC_FLAGS_QUERY_PENDING, &ec->flags)) { 427 ec_dbg_evt("Command(%s) submitted/blocked", 428 acpi_ec_cmd_string(ACPI_EC_COMMAND_QUERY)); 429 ec->nr_pending_queries++; 430 schedule_work(&ec->work); 431 } 432 } 433 434 static void acpi_ec_complete_query(struct acpi_ec *ec) 435 { 436 if (test_bit(EC_FLAGS_QUERY_PENDING, &ec->flags)) { 437 clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags); 438 ec_dbg_evt("Command(%s) unblocked", 439 acpi_ec_cmd_string(ACPI_EC_COMMAND_QUERY)); 440 } 441 } 442 443 static bool acpi_ec_guard_event(struct acpi_ec *ec) 444 { 445 bool guarded = true; 446 unsigned long flags; 447 448 spin_lock_irqsave(&ec->lock, flags); 449 /* 450 * If firmware SCI_EVT clearing timing is "event", we actually 451 * don't know when the SCI_EVT will be cleared by firmware after 452 * evaluating _Qxx, so we need to re-check SCI_EVT after waiting an 453 * acceptable period. 454 * 455 * The guarding period begins when EC_FLAGS_QUERY_PENDING is 456 * flagged, which means SCI_EVT check has just been performed. 457 * But if the current transaction is ACPI_EC_COMMAND_QUERY, the 458 * guarding should have already been performed (via 459 * EC_FLAGS_QUERY_GUARDING) and should not be applied so that the 460 * ACPI_EC_COMMAND_QUERY transaction can be transitioned into 461 * ACPI_EC_COMMAND_POLL state immediately. 462 */ 463 if (ec_event_clearing == ACPI_EC_EVT_TIMING_STATUS || 464 ec_event_clearing == ACPI_EC_EVT_TIMING_QUERY || 465 !test_bit(EC_FLAGS_QUERY_PENDING, &ec->flags) || 466 (ec->curr && ec->curr->command == ACPI_EC_COMMAND_QUERY)) 467 guarded = false; 468 spin_unlock_irqrestore(&ec->lock, flags); 469 return guarded; 470 } 471 472 static int ec_transaction_polled(struct acpi_ec *ec) 473 { 474 unsigned long flags; 475 int ret = 0; 476 477 spin_lock_irqsave(&ec->lock, flags); 478 if (ec->curr && (ec->curr->flags & ACPI_EC_COMMAND_POLL)) 479 ret = 1; 480 spin_unlock_irqrestore(&ec->lock, flags); 481 return ret; 482 } 483 484 static int ec_transaction_completed(struct acpi_ec *ec) 485 { 486 unsigned long flags; 487 int ret = 0; 488 489 spin_lock_irqsave(&ec->lock, flags); 490 if (ec->curr && (ec->curr->flags & ACPI_EC_COMMAND_COMPLETE)) 491 ret = 1; 492 spin_unlock_irqrestore(&ec->lock, flags); 493 return ret; 494 } 495 496 static inline void ec_transaction_transition(struct acpi_ec *ec, unsigned long flag) 497 { 498 ec->curr->flags |= flag; 499 if (ec->curr->command == ACPI_EC_COMMAND_QUERY) { 500 if (ec_event_clearing == ACPI_EC_EVT_TIMING_STATUS && 501 flag == ACPI_EC_COMMAND_POLL) 502 acpi_ec_complete_query(ec); 503 if (ec_event_clearing == ACPI_EC_EVT_TIMING_QUERY && 504 flag == ACPI_EC_COMMAND_COMPLETE) 505 acpi_ec_complete_query(ec); 506 if (ec_event_clearing == ACPI_EC_EVT_TIMING_EVENT && 507 flag == ACPI_EC_COMMAND_COMPLETE) 508 set_bit(EC_FLAGS_QUERY_GUARDING, &ec->flags); 509 } 510 } 511 512 static void advance_transaction(struct acpi_ec *ec) 513 { 514 struct transaction *t; 515 u8 status; 516 bool wakeup = false; 517 518 ec_dbg_stm("%s (%d)", in_interrupt() ? "IRQ" : "TASK", 519 smp_processor_id()); 520 /* 521 * By always clearing STS before handling all indications, we can 522 * ensure a hardware STS 0->1 change after this clearing can always 523 * trigger a GPE interrupt. 524 */ 525 acpi_ec_clear_gpe(ec); 526 status = acpi_ec_read_status(ec); 527 t = ec->curr; 528 /* 529 * Another IRQ or a guarded polling mode advancement is detected, 530 * the next QR_EC submission is then allowed. 531 */ 532 if (!t || !(t->flags & ACPI_EC_COMMAND_POLL)) { 533 if (ec_event_clearing == ACPI_EC_EVT_TIMING_EVENT && 534 (!ec->nr_pending_queries || 535 test_bit(EC_FLAGS_QUERY_GUARDING, &ec->flags))) { 536 clear_bit(EC_FLAGS_QUERY_GUARDING, &ec->flags); 537 acpi_ec_complete_query(ec); 538 } 539 } 540 if (!t) 541 goto err; 542 if (t->flags & ACPI_EC_COMMAND_POLL) { 543 if (t->wlen > t->wi) { 544 if ((status & ACPI_EC_FLAG_IBF) == 0) 545 acpi_ec_write_data(ec, t->wdata[t->wi++]); 546 else 547 goto err; 548 } else if (t->rlen > t->ri) { 549 if ((status & ACPI_EC_FLAG_OBF) == 1) { 550 t->rdata[t->ri++] = acpi_ec_read_data(ec); 551 if (t->rlen == t->ri) { 552 ec_transaction_transition(ec, ACPI_EC_COMMAND_COMPLETE); 553 if (t->command == ACPI_EC_COMMAND_QUERY) 554 ec_dbg_evt("Command(%s) completed by hardware", 555 acpi_ec_cmd_string(ACPI_EC_COMMAND_QUERY)); 556 wakeup = true; 557 } 558 } else 559 goto err; 560 } else if (t->wlen == t->wi && 561 (status & ACPI_EC_FLAG_IBF) == 0) { 562 ec_transaction_transition(ec, ACPI_EC_COMMAND_COMPLETE); 563 wakeup = true; 564 } 565 goto out; 566 } else { 567 if (EC_FLAGS_QUERY_HANDSHAKE && 568 !(status & ACPI_EC_FLAG_SCI) && 569 (t->command == ACPI_EC_COMMAND_QUERY)) { 570 ec_transaction_transition(ec, ACPI_EC_COMMAND_POLL); 571 t->rdata[t->ri++] = 0x00; 572 ec_transaction_transition(ec, ACPI_EC_COMMAND_COMPLETE); 573 ec_dbg_evt("Command(%s) completed by software", 574 acpi_ec_cmd_string(ACPI_EC_COMMAND_QUERY)); 575 wakeup = true; 576 } else if ((status & ACPI_EC_FLAG_IBF) == 0) { 577 acpi_ec_write_cmd(ec, t->command); 578 ec_transaction_transition(ec, ACPI_EC_COMMAND_POLL); 579 } else 580 goto err; 581 goto out; 582 } 583 err: 584 /* 585 * If SCI bit is set, then don't think it's a false IRQ 586 * otherwise will take a not handled IRQ as a false one. 587 */ 588 if (!(status & ACPI_EC_FLAG_SCI)) { 589 if (in_interrupt() && t) { 590 if (t->irq_count < ec_storm_threshold) 591 ++t->irq_count; 592 /* Allow triggering on 0 threshold */ 593 if (t->irq_count == ec_storm_threshold) 594 acpi_ec_set_storm(ec, EC_FLAGS_COMMAND_STORM); 595 } 596 } 597 out: 598 if (status & ACPI_EC_FLAG_SCI) 599 acpi_ec_submit_query(ec); 600 if (wakeup && in_interrupt()) 601 wake_up(&ec->wait); 602 } 603 604 static void start_transaction(struct acpi_ec *ec) 605 { 606 ec->curr->irq_count = ec->curr->wi = ec->curr->ri = 0; 607 ec->curr->flags = 0; 608 } 609 610 static int ec_guard(struct acpi_ec *ec) 611 { 612 unsigned long guard = usecs_to_jiffies(ec_polling_guard); 613 unsigned long timeout = ec->timestamp + guard; 614 615 /* Ensure guarding period before polling EC status */ 616 do { 617 if (ec_busy_polling) { 618 /* Perform busy polling */ 619 if (ec_transaction_completed(ec)) 620 return 0; 621 udelay(jiffies_to_usecs(guard)); 622 } else { 623 /* 624 * Perform wait polling 625 * 1. Wait the transaction to be completed by the 626 * GPE handler after the transaction enters 627 * ACPI_EC_COMMAND_POLL state. 628 * 2. A special guarding logic is also required 629 * for event clearing mode "event" before the 630 * transaction enters ACPI_EC_COMMAND_POLL 631 * state. 632 */ 633 if (!ec_transaction_polled(ec) && 634 !acpi_ec_guard_event(ec)) 635 break; 636 if (wait_event_timeout(ec->wait, 637 ec_transaction_completed(ec), 638 guard)) 639 return 0; 640 } 641 } while (time_before(jiffies, timeout)); 642 return -ETIME; 643 } 644 645 static int ec_poll(struct acpi_ec *ec) 646 { 647 unsigned long flags; 648 int repeat = 5; /* number of command restarts */ 649 650 while (repeat--) { 651 unsigned long delay = jiffies + 652 msecs_to_jiffies(ec_delay); 653 do { 654 if (!ec_guard(ec)) 655 return 0; 656 spin_lock_irqsave(&ec->lock, flags); 657 advance_transaction(ec); 658 spin_unlock_irqrestore(&ec->lock, flags); 659 } while (time_before(jiffies, delay)); 660 pr_debug("controller reset, restart transaction\n"); 661 spin_lock_irqsave(&ec->lock, flags); 662 start_transaction(ec); 663 spin_unlock_irqrestore(&ec->lock, flags); 664 } 665 return -ETIME; 666 } 667 668 static int acpi_ec_transaction_unlocked(struct acpi_ec *ec, 669 struct transaction *t) 670 { 671 unsigned long tmp; 672 int ret = 0; 673 674 /* start transaction */ 675 spin_lock_irqsave(&ec->lock, tmp); 676 /* Enable GPE for command processing (IBF=0/OBF=1) */ 677 if (!acpi_ec_submit_flushable_request(ec)) { 678 ret = -EINVAL; 679 goto unlock; 680 } 681 ec_dbg_ref(ec, "Increase command"); 682 /* following two actions should be kept atomic */ 683 ec->curr = t; 684 ec_dbg_req("Command(%s) started", acpi_ec_cmd_string(t->command)); 685 start_transaction(ec); 686 spin_unlock_irqrestore(&ec->lock, tmp); 687 688 ret = ec_poll(ec); 689 690 spin_lock_irqsave(&ec->lock, tmp); 691 if (t->irq_count == ec_storm_threshold) 692 acpi_ec_clear_storm(ec, EC_FLAGS_COMMAND_STORM); 693 ec_dbg_req("Command(%s) stopped", acpi_ec_cmd_string(t->command)); 694 ec->curr = NULL; 695 /* Disable GPE for command processing (IBF=0/OBF=1) */ 696 acpi_ec_complete_request(ec); 697 ec_dbg_ref(ec, "Decrease command"); 698 unlock: 699 spin_unlock_irqrestore(&ec->lock, tmp); 700 return ret; 701 } 702 703 static int acpi_ec_transaction(struct acpi_ec *ec, struct transaction *t) 704 { 705 int status; 706 u32 glk; 707 708 if (!ec || (!t) || (t->wlen && !t->wdata) || (t->rlen && !t->rdata)) 709 return -EINVAL; 710 if (t->rdata) 711 memset(t->rdata, 0, t->rlen); 712 713 mutex_lock(&ec->mutex); 714 if (ec->global_lock) { 715 status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk); 716 if (ACPI_FAILURE(status)) { 717 status = -ENODEV; 718 goto unlock; 719 } 720 } 721 722 status = acpi_ec_transaction_unlocked(ec, t); 723 724 if (ec->global_lock) 725 acpi_release_global_lock(glk); 726 unlock: 727 mutex_unlock(&ec->mutex); 728 return status; 729 } 730 731 static int acpi_ec_burst_enable(struct acpi_ec *ec) 732 { 733 u8 d; 734 struct transaction t = {.command = ACPI_EC_BURST_ENABLE, 735 .wdata = NULL, .rdata = &d, 736 .wlen = 0, .rlen = 1}; 737 738 return acpi_ec_transaction(ec, &t); 739 } 740 741 static int acpi_ec_burst_disable(struct acpi_ec *ec) 742 { 743 struct transaction t = {.command = ACPI_EC_BURST_DISABLE, 744 .wdata = NULL, .rdata = NULL, 745 .wlen = 0, .rlen = 0}; 746 747 return (acpi_ec_read_status(ec) & ACPI_EC_FLAG_BURST) ? 748 acpi_ec_transaction(ec, &t) : 0; 749 } 750 751 static int acpi_ec_read(struct acpi_ec *ec, u8 address, u8 *data) 752 { 753 int result; 754 u8 d; 755 struct transaction t = {.command = ACPI_EC_COMMAND_READ, 756 .wdata = &address, .rdata = &d, 757 .wlen = 1, .rlen = 1}; 758 759 result = acpi_ec_transaction(ec, &t); 760 *data = d; 761 return result; 762 } 763 764 static int acpi_ec_write(struct acpi_ec *ec, u8 address, u8 data) 765 { 766 u8 wdata[2] = { address, data }; 767 struct transaction t = {.command = ACPI_EC_COMMAND_WRITE, 768 .wdata = wdata, .rdata = NULL, 769 .wlen = 2, .rlen = 0}; 770 771 return acpi_ec_transaction(ec, &t); 772 } 773 774 int ec_read(u8 addr, u8 *val) 775 { 776 int err; 777 u8 temp_data; 778 779 if (!first_ec) 780 return -ENODEV; 781 782 err = acpi_ec_read(first_ec, addr, &temp_data); 783 784 if (!err) { 785 *val = temp_data; 786 return 0; 787 } 788 return err; 789 } 790 EXPORT_SYMBOL(ec_read); 791 792 int ec_write(u8 addr, u8 val) 793 { 794 int err; 795 796 if (!first_ec) 797 return -ENODEV; 798 799 err = acpi_ec_write(first_ec, addr, val); 800 801 return err; 802 } 803 EXPORT_SYMBOL(ec_write); 804 805 int ec_transaction(u8 command, 806 const u8 *wdata, unsigned wdata_len, 807 u8 *rdata, unsigned rdata_len) 808 { 809 struct transaction t = {.command = command, 810 .wdata = wdata, .rdata = rdata, 811 .wlen = wdata_len, .rlen = rdata_len}; 812 813 if (!first_ec) 814 return -ENODEV; 815 816 return acpi_ec_transaction(first_ec, &t); 817 } 818 EXPORT_SYMBOL(ec_transaction); 819 820 /* Get the handle to the EC device */ 821 acpi_handle ec_get_handle(void) 822 { 823 if (!first_ec) 824 return NULL; 825 return first_ec->handle; 826 } 827 EXPORT_SYMBOL(ec_get_handle); 828 829 /* 830 * Process _Q events that might have accumulated in the EC. 831 * Run with locked ec mutex. 832 */ 833 static void acpi_ec_clear(struct acpi_ec *ec) 834 { 835 int i, status; 836 u8 value = 0; 837 838 for (i = 0; i < ACPI_EC_CLEAR_MAX; i++) { 839 status = acpi_ec_query(ec, &value); 840 if (status || !value) 841 break; 842 } 843 844 if (unlikely(i == ACPI_EC_CLEAR_MAX)) 845 pr_warn("Warning: Maximum of %d stale EC events cleared\n", i); 846 else 847 pr_info("%d stale EC events cleared\n", i); 848 } 849 850 static void acpi_ec_start(struct acpi_ec *ec, bool resuming) 851 { 852 unsigned long flags; 853 854 spin_lock_irqsave(&ec->lock, flags); 855 if (!test_and_set_bit(EC_FLAGS_STARTED, &ec->flags)) { 856 ec_dbg_drv("Starting EC"); 857 /* Enable GPE for event processing (SCI_EVT=1) */ 858 if (!resuming) { 859 acpi_ec_submit_request(ec); 860 ec_dbg_ref(ec, "Increase driver"); 861 } 862 ec_log_drv("EC started"); 863 } 864 spin_unlock_irqrestore(&ec->lock, flags); 865 } 866 867 static bool acpi_ec_stopped(struct acpi_ec *ec) 868 { 869 unsigned long flags; 870 bool flushed; 871 872 spin_lock_irqsave(&ec->lock, flags); 873 flushed = acpi_ec_flushed(ec); 874 spin_unlock_irqrestore(&ec->lock, flags); 875 return flushed; 876 } 877 878 static void acpi_ec_stop(struct acpi_ec *ec, bool suspending) 879 { 880 unsigned long flags; 881 882 spin_lock_irqsave(&ec->lock, flags); 883 if (acpi_ec_started(ec)) { 884 ec_dbg_drv("Stopping EC"); 885 set_bit(EC_FLAGS_STOPPED, &ec->flags); 886 spin_unlock_irqrestore(&ec->lock, flags); 887 wait_event(ec->wait, acpi_ec_stopped(ec)); 888 spin_lock_irqsave(&ec->lock, flags); 889 /* Disable GPE for event processing (SCI_EVT=1) */ 890 if (!suspending) { 891 acpi_ec_complete_request(ec); 892 ec_dbg_ref(ec, "Decrease driver"); 893 } 894 clear_bit(EC_FLAGS_STARTED, &ec->flags); 895 clear_bit(EC_FLAGS_STOPPED, &ec->flags); 896 ec_log_drv("EC stopped"); 897 } 898 spin_unlock_irqrestore(&ec->lock, flags); 899 } 900 901 void acpi_ec_block_transactions(void) 902 { 903 struct acpi_ec *ec = first_ec; 904 905 if (!ec) 906 return; 907 908 mutex_lock(&ec->mutex); 909 /* Prevent transactions from being carried out */ 910 acpi_ec_stop(ec, true); 911 mutex_unlock(&ec->mutex); 912 } 913 914 void acpi_ec_unblock_transactions(void) 915 { 916 struct acpi_ec *ec = first_ec; 917 918 if (!ec) 919 return; 920 921 /* Allow transactions to be carried out again */ 922 acpi_ec_start(ec, true); 923 924 if (EC_FLAGS_CLEAR_ON_RESUME) 925 acpi_ec_clear(ec); 926 } 927 928 void acpi_ec_unblock_transactions_early(void) 929 { 930 /* 931 * Allow transactions to happen again (this function is called from 932 * atomic context during wakeup, so we don't need to acquire the mutex). 933 */ 934 if (first_ec) 935 acpi_ec_start(first_ec, true); 936 } 937 938 /* -------------------------------------------------------------------------- 939 Event Management 940 -------------------------------------------------------------------------- */ 941 static struct acpi_ec_query_handler * 942 acpi_ec_get_query_handler(struct acpi_ec_query_handler *handler) 943 { 944 if (handler) 945 kref_get(&handler->kref); 946 return handler; 947 } 948 949 static struct acpi_ec_query_handler * 950 acpi_ec_get_query_handler_by_value(struct acpi_ec *ec, u8 value) 951 { 952 struct acpi_ec_query_handler *handler; 953 bool found = false; 954 955 mutex_lock(&ec->mutex); 956 list_for_each_entry(handler, &ec->list, node) { 957 if (value == handler->query_bit) { 958 found = true; 959 break; 960 } 961 } 962 mutex_unlock(&ec->mutex); 963 return found ? acpi_ec_get_query_handler(handler) : NULL; 964 } 965 966 static void acpi_ec_query_handler_release(struct kref *kref) 967 { 968 struct acpi_ec_query_handler *handler = 969 container_of(kref, struct acpi_ec_query_handler, kref); 970 971 kfree(handler); 972 } 973 974 static void acpi_ec_put_query_handler(struct acpi_ec_query_handler *handler) 975 { 976 kref_put(&handler->kref, acpi_ec_query_handler_release); 977 } 978 979 int acpi_ec_add_query_handler(struct acpi_ec *ec, u8 query_bit, 980 acpi_handle handle, acpi_ec_query_func func, 981 void *data) 982 { 983 struct acpi_ec_query_handler *handler = 984 kzalloc(sizeof(struct acpi_ec_query_handler), GFP_KERNEL); 985 986 if (!handler) 987 return -ENOMEM; 988 989 handler->query_bit = query_bit; 990 handler->handle = handle; 991 handler->func = func; 992 handler->data = data; 993 mutex_lock(&ec->mutex); 994 kref_init(&handler->kref); 995 list_add(&handler->node, &ec->list); 996 mutex_unlock(&ec->mutex); 997 return 0; 998 } 999 EXPORT_SYMBOL_GPL(acpi_ec_add_query_handler); 1000 1001 static void acpi_ec_remove_query_handlers(struct acpi_ec *ec, 1002 bool remove_all, u8 query_bit) 1003 { 1004 struct acpi_ec_query_handler *handler, *tmp; 1005 LIST_HEAD(free_list); 1006 1007 mutex_lock(&ec->mutex); 1008 list_for_each_entry_safe(handler, tmp, &ec->list, node) { 1009 if (remove_all || query_bit == handler->query_bit) { 1010 list_del_init(&handler->node); 1011 list_add(&handler->node, &free_list); 1012 } 1013 } 1014 mutex_unlock(&ec->mutex); 1015 list_for_each_entry_safe(handler, tmp, &free_list, node) 1016 acpi_ec_put_query_handler(handler); 1017 } 1018 1019 void acpi_ec_remove_query_handler(struct acpi_ec *ec, u8 query_bit) 1020 { 1021 acpi_ec_remove_query_handlers(ec, false, query_bit); 1022 } 1023 EXPORT_SYMBOL_GPL(acpi_ec_remove_query_handler); 1024 1025 static struct acpi_ec_query *acpi_ec_create_query(u8 *pval) 1026 { 1027 struct acpi_ec_query *q; 1028 struct transaction *t; 1029 1030 q = kzalloc(sizeof (struct acpi_ec_query), GFP_KERNEL); 1031 if (!q) 1032 return NULL; 1033 INIT_WORK(&q->work, acpi_ec_event_processor); 1034 t = &q->transaction; 1035 t->command = ACPI_EC_COMMAND_QUERY; 1036 t->rdata = pval; 1037 t->rlen = 1; 1038 return q; 1039 } 1040 1041 static void acpi_ec_delete_query(struct acpi_ec_query *q) 1042 { 1043 if (q) { 1044 if (q->handler) 1045 acpi_ec_put_query_handler(q->handler); 1046 kfree(q); 1047 } 1048 } 1049 1050 static void acpi_ec_event_processor(struct work_struct *work) 1051 { 1052 struct acpi_ec_query *q = container_of(work, struct acpi_ec_query, work); 1053 struct acpi_ec_query_handler *handler = q->handler; 1054 1055 ec_dbg_evt("Query(0x%02x) started", handler->query_bit); 1056 if (handler->func) 1057 handler->func(handler->data); 1058 else if (handler->handle) 1059 acpi_evaluate_object(handler->handle, NULL, NULL, NULL); 1060 ec_dbg_evt("Query(0x%02x) stopped", handler->query_bit); 1061 acpi_ec_delete_query(q); 1062 } 1063 1064 static int acpi_ec_query(struct acpi_ec *ec, u8 *data) 1065 { 1066 u8 value = 0; 1067 int result; 1068 struct acpi_ec_query *q; 1069 1070 q = acpi_ec_create_query(&value); 1071 if (!q) 1072 return -ENOMEM; 1073 1074 /* 1075 * Query the EC to find out which _Qxx method we need to evaluate. 1076 * Note that successful completion of the query causes the ACPI_EC_SCI 1077 * bit to be cleared (and thus clearing the interrupt source). 1078 */ 1079 result = acpi_ec_transaction(ec, &q->transaction); 1080 if (!value) 1081 result = -ENODATA; 1082 if (result) 1083 goto err_exit; 1084 1085 q->handler = acpi_ec_get_query_handler_by_value(ec, value); 1086 if (!q->handler) { 1087 result = -ENODATA; 1088 goto err_exit; 1089 } 1090 1091 /* 1092 * It is reported that _Qxx are evaluated in a parallel way on 1093 * Windows: 1094 * https://bugzilla.kernel.org/show_bug.cgi?id=94411 1095 * 1096 * Put this log entry before schedule_work() in order to make 1097 * it appearing before any other log entries occurred during the 1098 * work queue execution. 1099 */ 1100 ec_dbg_evt("Query(0x%02x) scheduled", value); 1101 if (!schedule_work(&q->work)) { 1102 ec_dbg_evt("Query(0x%02x) overlapped", value); 1103 result = -EBUSY; 1104 } 1105 1106 err_exit: 1107 if (result) 1108 acpi_ec_delete_query(q); 1109 if (data) 1110 *data = value; 1111 return result; 1112 } 1113 1114 static void acpi_ec_check_event(struct acpi_ec *ec) 1115 { 1116 unsigned long flags; 1117 1118 if (ec_event_clearing == ACPI_EC_EVT_TIMING_EVENT) { 1119 if (ec_guard(ec)) { 1120 spin_lock_irqsave(&ec->lock, flags); 1121 /* 1122 * Take care of the SCI_EVT unless no one else is 1123 * taking care of it. 1124 */ 1125 if (!ec->curr) 1126 advance_transaction(ec); 1127 spin_unlock_irqrestore(&ec->lock, flags); 1128 } 1129 } 1130 } 1131 1132 static void acpi_ec_event_handler(struct work_struct *work) 1133 { 1134 unsigned long flags; 1135 struct acpi_ec *ec = container_of(work, struct acpi_ec, work); 1136 1137 ec_dbg_evt("Event started"); 1138 1139 spin_lock_irqsave(&ec->lock, flags); 1140 while (ec->nr_pending_queries) { 1141 spin_unlock_irqrestore(&ec->lock, flags); 1142 (void)acpi_ec_query(ec, NULL); 1143 spin_lock_irqsave(&ec->lock, flags); 1144 ec->nr_pending_queries--; 1145 /* 1146 * Before exit, make sure that this work item can be 1147 * scheduled again. There might be QR_EC failures, leaving 1148 * EC_FLAGS_QUERY_PENDING uncleared and preventing this work 1149 * item from being scheduled again. 1150 */ 1151 if (!ec->nr_pending_queries) { 1152 if (ec_event_clearing == ACPI_EC_EVT_TIMING_STATUS || 1153 ec_event_clearing == ACPI_EC_EVT_TIMING_QUERY) 1154 acpi_ec_complete_query(ec); 1155 } 1156 } 1157 spin_unlock_irqrestore(&ec->lock, flags); 1158 1159 ec_dbg_evt("Event stopped"); 1160 1161 acpi_ec_check_event(ec); 1162 } 1163 1164 static u32 acpi_ec_gpe_handler(acpi_handle gpe_device, 1165 u32 gpe_number, void *data) 1166 { 1167 unsigned long flags; 1168 struct acpi_ec *ec = data; 1169 1170 spin_lock_irqsave(&ec->lock, flags); 1171 advance_transaction(ec); 1172 spin_unlock_irqrestore(&ec->lock, flags); 1173 return ACPI_INTERRUPT_HANDLED; 1174 } 1175 1176 /* -------------------------------------------------------------------------- 1177 * Address Space Management 1178 * -------------------------------------------------------------------------- */ 1179 1180 static acpi_status 1181 acpi_ec_space_handler(u32 function, acpi_physical_address address, 1182 u32 bits, u64 *value64, 1183 void *handler_context, void *region_context) 1184 { 1185 struct acpi_ec *ec = handler_context; 1186 int result = 0, i, bytes = bits / 8; 1187 u8 *value = (u8 *)value64; 1188 1189 if ((address > 0xFF) || !value || !handler_context) 1190 return AE_BAD_PARAMETER; 1191 1192 if (function != ACPI_READ && function != ACPI_WRITE) 1193 return AE_BAD_PARAMETER; 1194 1195 if (ec_busy_polling || bits > 8) 1196 acpi_ec_burst_enable(ec); 1197 1198 for (i = 0; i < bytes; ++i, ++address, ++value) 1199 result = (function == ACPI_READ) ? 1200 acpi_ec_read(ec, address, value) : 1201 acpi_ec_write(ec, address, *value); 1202 1203 if (ec_busy_polling || bits > 8) 1204 acpi_ec_burst_disable(ec); 1205 1206 switch (result) { 1207 case -EINVAL: 1208 return AE_BAD_PARAMETER; 1209 case -ENODEV: 1210 return AE_NOT_FOUND; 1211 case -ETIME: 1212 return AE_TIME; 1213 default: 1214 return AE_OK; 1215 } 1216 } 1217 1218 /* -------------------------------------------------------------------------- 1219 * Driver Interface 1220 * -------------------------------------------------------------------------- */ 1221 1222 static acpi_status 1223 ec_parse_io_ports(struct acpi_resource *resource, void *context); 1224 1225 static struct acpi_ec *make_acpi_ec(void) 1226 { 1227 struct acpi_ec *ec = kzalloc(sizeof(struct acpi_ec), GFP_KERNEL); 1228 1229 if (!ec) 1230 return NULL; 1231 ec->flags = 1 << EC_FLAGS_QUERY_PENDING; 1232 mutex_init(&ec->mutex); 1233 init_waitqueue_head(&ec->wait); 1234 INIT_LIST_HEAD(&ec->list); 1235 spin_lock_init(&ec->lock); 1236 INIT_WORK(&ec->work, acpi_ec_event_handler); 1237 ec->timestamp = jiffies; 1238 return ec; 1239 } 1240 1241 static acpi_status 1242 acpi_ec_register_query_methods(acpi_handle handle, u32 level, 1243 void *context, void **return_value) 1244 { 1245 char node_name[5]; 1246 struct acpi_buffer buffer = { sizeof(node_name), node_name }; 1247 struct acpi_ec *ec = context; 1248 int value = 0; 1249 acpi_status status; 1250 1251 status = acpi_get_name(handle, ACPI_SINGLE_NAME, &buffer); 1252 1253 if (ACPI_SUCCESS(status) && sscanf(node_name, "_Q%x", &value) == 1) 1254 acpi_ec_add_query_handler(ec, value, handle, NULL, NULL); 1255 return AE_OK; 1256 } 1257 1258 static acpi_status 1259 ec_parse_device(acpi_handle handle, u32 Level, void *context, void **retval) 1260 { 1261 acpi_status status; 1262 unsigned long long tmp = 0; 1263 struct acpi_ec *ec = context; 1264 1265 /* clear addr values, ec_parse_io_ports depend on it */ 1266 ec->command_addr = ec->data_addr = 0; 1267 1268 status = acpi_walk_resources(handle, METHOD_NAME__CRS, 1269 ec_parse_io_ports, ec); 1270 if (ACPI_FAILURE(status)) 1271 return status; 1272 1273 /* Get GPE bit assignment (EC events). */ 1274 /* TODO: Add support for _GPE returning a package */ 1275 status = acpi_evaluate_integer(handle, "_GPE", NULL, &tmp); 1276 if (ACPI_FAILURE(status)) 1277 return status; 1278 ec->gpe = tmp; 1279 /* Use the global lock for all EC transactions? */ 1280 tmp = 0; 1281 acpi_evaluate_integer(handle, "_GLK", NULL, &tmp); 1282 ec->global_lock = tmp; 1283 ec->handle = handle; 1284 return AE_CTRL_TERMINATE; 1285 } 1286 1287 static int ec_install_handlers(struct acpi_ec *ec) 1288 { 1289 acpi_status status; 1290 1291 acpi_ec_start(ec, false); 1292 1293 if (!test_bit(EC_FLAGS_EC_HANDLER_INSTALLED, &ec->flags)) { 1294 status = acpi_install_address_space_handler(ec->handle, 1295 ACPI_ADR_SPACE_EC, 1296 &acpi_ec_space_handler, 1297 NULL, ec); 1298 if (ACPI_FAILURE(status)) { 1299 if (status == AE_NOT_FOUND) { 1300 /* 1301 * Maybe OS fails in evaluating the _REG 1302 * object. The AE_NOT_FOUND error will be 1303 * ignored and OS * continue to initialize 1304 * EC. 1305 */ 1306 pr_err("Fail in evaluating the _REG object" 1307 " of EC device. Broken bios is suspected.\n"); 1308 } else { 1309 acpi_ec_stop(ec, false); 1310 return -ENODEV; 1311 } 1312 } 1313 set_bit(EC_FLAGS_EC_HANDLER_INSTALLED, &ec->flags); 1314 } 1315 1316 if (!test_bit(EC_FLAGS_GPE_HANDLER_INSTALLED, &ec->flags)) { 1317 status = acpi_install_gpe_raw_handler(NULL, ec->gpe, 1318 ACPI_GPE_EDGE_TRIGGERED, 1319 &acpi_ec_gpe_handler, ec); 1320 /* This is not fatal as we can poll EC events */ 1321 if (ACPI_SUCCESS(status)) { 1322 set_bit(EC_FLAGS_GPE_HANDLER_INSTALLED, &ec->flags); 1323 if (test_bit(EC_FLAGS_STARTED, &ec->flags) && 1324 ec->reference_count >= 1) 1325 acpi_ec_enable_gpe(ec, true); 1326 } 1327 } 1328 1329 return 0; 1330 } 1331 1332 static void ec_remove_handlers(struct acpi_ec *ec) 1333 { 1334 acpi_ec_stop(ec, false); 1335 1336 if (test_bit(EC_FLAGS_EC_HANDLER_INSTALLED, &ec->flags)) { 1337 if (ACPI_FAILURE(acpi_remove_address_space_handler(ec->handle, 1338 ACPI_ADR_SPACE_EC, &acpi_ec_space_handler))) 1339 pr_err("failed to remove space handler\n"); 1340 clear_bit(EC_FLAGS_EC_HANDLER_INSTALLED, &ec->flags); 1341 } 1342 1343 if (test_bit(EC_FLAGS_GPE_HANDLER_INSTALLED, &ec->flags)) { 1344 if (ACPI_FAILURE(acpi_remove_gpe_handler(NULL, ec->gpe, 1345 &acpi_ec_gpe_handler))) 1346 pr_err("failed to remove gpe handler\n"); 1347 clear_bit(EC_FLAGS_GPE_HANDLER_INSTALLED, &ec->flags); 1348 } 1349 } 1350 1351 static int acpi_ec_add(struct acpi_device *device) 1352 { 1353 struct acpi_ec *ec = NULL; 1354 int ret; 1355 1356 strcpy(acpi_device_name(device), ACPI_EC_DEVICE_NAME); 1357 strcpy(acpi_device_class(device), ACPI_EC_CLASS); 1358 1359 /* Check for boot EC */ 1360 if (boot_ec) { 1361 ec = boot_ec; 1362 boot_ec = NULL; 1363 ec_remove_handlers(ec); 1364 if (first_ec == ec) 1365 first_ec = NULL; 1366 } else { 1367 ec = make_acpi_ec(); 1368 if (!ec) 1369 return -ENOMEM; 1370 } 1371 if (ec_parse_device(device->handle, 0, ec, NULL) != 1372 AE_CTRL_TERMINATE) { 1373 kfree(ec); 1374 return -EINVAL; 1375 } 1376 1377 /* Find and register all query methods */ 1378 acpi_walk_namespace(ACPI_TYPE_METHOD, ec->handle, 1, 1379 acpi_ec_register_query_methods, NULL, ec, NULL); 1380 1381 if (!first_ec) 1382 first_ec = ec; 1383 device->driver_data = ec; 1384 1385 ret = !!request_region(ec->data_addr, 1, "EC data"); 1386 WARN(!ret, "Could not request EC data io port 0x%lx", ec->data_addr); 1387 ret = !!request_region(ec->command_addr, 1, "EC cmd"); 1388 WARN(!ret, "Could not request EC cmd io port 0x%lx", ec->command_addr); 1389 1390 pr_info("GPE = 0x%lx, I/O: command/status = 0x%lx, data = 0x%lx\n", 1391 ec->gpe, ec->command_addr, ec->data_addr); 1392 1393 ret = ec_install_handlers(ec); 1394 1395 /* Reprobe devices depending on the EC */ 1396 acpi_walk_dep_device_list(ec->handle); 1397 1398 /* EC is fully operational, allow queries */ 1399 clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags); 1400 1401 /* Clear stale _Q events if hardware might require that */ 1402 if (EC_FLAGS_CLEAR_ON_RESUME) 1403 acpi_ec_clear(ec); 1404 return ret; 1405 } 1406 1407 static int acpi_ec_remove(struct acpi_device *device) 1408 { 1409 struct acpi_ec *ec; 1410 1411 if (!device) 1412 return -EINVAL; 1413 1414 ec = acpi_driver_data(device); 1415 ec_remove_handlers(ec); 1416 acpi_ec_remove_query_handlers(ec, true, 0); 1417 release_region(ec->data_addr, 1); 1418 release_region(ec->command_addr, 1); 1419 device->driver_data = NULL; 1420 if (ec == first_ec) 1421 first_ec = NULL; 1422 kfree(ec); 1423 return 0; 1424 } 1425 1426 static acpi_status 1427 ec_parse_io_ports(struct acpi_resource *resource, void *context) 1428 { 1429 struct acpi_ec *ec = context; 1430 1431 if (resource->type != ACPI_RESOURCE_TYPE_IO) 1432 return AE_OK; 1433 1434 /* 1435 * The first address region returned is the data port, and 1436 * the second address region returned is the status/command 1437 * port. 1438 */ 1439 if (ec->data_addr == 0) 1440 ec->data_addr = resource->data.io.minimum; 1441 else if (ec->command_addr == 0) 1442 ec->command_addr = resource->data.io.minimum; 1443 else 1444 return AE_CTRL_TERMINATE; 1445 1446 return AE_OK; 1447 } 1448 1449 static const struct acpi_device_id ec_device_ids[] = { 1450 {"PNP0C09", 0}, 1451 {"", 0}, 1452 }; 1453 1454 int __init acpi_ec_dsdt_probe(void) 1455 { 1456 acpi_status status; 1457 1458 if (boot_ec) 1459 return 0; 1460 1461 /* 1462 * Finding EC from DSDT if there is no ECDT EC available. When this 1463 * function is invoked, ACPI tables have been fully loaded, we can 1464 * walk namespace now. 1465 */ 1466 boot_ec = make_acpi_ec(); 1467 if (!boot_ec) 1468 return -ENOMEM; 1469 status = acpi_get_devices(ec_device_ids[0].id, 1470 ec_parse_device, boot_ec, NULL); 1471 if (ACPI_FAILURE(status) || !boot_ec->handle) 1472 return -ENODEV; 1473 if (!ec_install_handlers(boot_ec)) { 1474 first_ec = boot_ec; 1475 return 0; 1476 } 1477 return -EFAULT; 1478 } 1479 1480 #if 0 1481 /* 1482 * Some EC firmware variations refuses to respond QR_EC when SCI_EVT is not 1483 * set, for which case, we complete the QR_EC without issuing it to the 1484 * firmware. 1485 * https://bugzilla.kernel.org/show_bug.cgi?id=82611 1486 * https://bugzilla.kernel.org/show_bug.cgi?id=97381 1487 */ 1488 static int ec_flag_query_handshake(const struct dmi_system_id *id) 1489 { 1490 pr_debug("Detected the EC firmware requiring QR_EC issued when SCI_EVT set\n"); 1491 EC_FLAGS_QUERY_HANDSHAKE = 1; 1492 return 0; 1493 } 1494 #endif 1495 1496 /* 1497 * On some hardware it is necessary to clear events accumulated by the EC during 1498 * sleep. These ECs stop reporting GPEs until they are manually polled, if too 1499 * many events are accumulated. (e.g. Samsung Series 5/9 notebooks) 1500 * 1501 * https://bugzilla.kernel.org/show_bug.cgi?id=44161 1502 * 1503 * Ideally, the EC should also be instructed NOT to accumulate events during 1504 * sleep (which Windows seems to do somehow), but the interface to control this 1505 * behaviour is not known at this time. 1506 * 1507 * Models known to be affected are Samsung 530Uxx/535Uxx/540Uxx/550Pxx/900Xxx, 1508 * however it is very likely that other Samsung models are affected. 1509 * 1510 * On systems which don't accumulate _Q events during sleep, this extra check 1511 * should be harmless. 1512 */ 1513 static int ec_clear_on_resume(const struct dmi_system_id *id) 1514 { 1515 pr_debug("Detected system needing EC poll on resume.\n"); 1516 EC_FLAGS_CLEAR_ON_RESUME = 1; 1517 ec_event_clearing = ACPI_EC_EVT_TIMING_STATUS; 1518 return 0; 1519 } 1520 1521 static int ec_correct_ecdt(const struct dmi_system_id *id) 1522 { 1523 pr_debug("Detected system needing ECDT address correction.\n"); 1524 EC_FLAGS_CORRECT_ECDT = 1; 1525 return 0; 1526 } 1527 1528 static struct dmi_system_id ec_dmi_table[] __initdata = { 1529 { 1530 ec_correct_ecdt, "Asus L4R", { 1531 DMI_MATCH(DMI_BIOS_VERSION, "1008.006"), 1532 DMI_MATCH(DMI_PRODUCT_NAME, "L4R"), 1533 DMI_MATCH(DMI_BOARD_NAME, "L4R") }, NULL}, 1534 { 1535 ec_correct_ecdt, "Asus M6R", { 1536 DMI_MATCH(DMI_BIOS_VERSION, "0207"), 1537 DMI_MATCH(DMI_PRODUCT_NAME, "M6R"), 1538 DMI_MATCH(DMI_BOARD_NAME, "M6R") }, NULL}, 1539 { 1540 ec_correct_ecdt, "MSI MS-171F", { 1541 DMI_MATCH(DMI_SYS_VENDOR, "Micro-Star"), 1542 DMI_MATCH(DMI_PRODUCT_NAME, "MS-171F"),}, NULL}, 1543 { 1544 ec_clear_on_resume, "Samsung hardware", { 1545 DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD.")}, NULL}, 1546 {}, 1547 }; 1548 1549 int __init acpi_ec_ecdt_probe(void) 1550 { 1551 int ret = 0; 1552 acpi_status status; 1553 struct acpi_table_ecdt *ecdt_ptr; 1554 1555 boot_ec = make_acpi_ec(); 1556 if (!boot_ec) 1557 return -ENOMEM; 1558 /* 1559 * Generate a boot ec context 1560 */ 1561 dmi_check_system(ec_dmi_table); 1562 status = acpi_get_table(ACPI_SIG_ECDT, 1, 1563 (struct acpi_table_header **)&ecdt_ptr); 1564 if (ACPI_FAILURE(status)) { 1565 ret = -ENODEV; 1566 goto error; 1567 } 1568 1569 if (!ecdt_ptr->control.address || !ecdt_ptr->data.address) { 1570 /* 1571 * Asus X50GL: 1572 * https://bugzilla.kernel.org/show_bug.cgi?id=11880 1573 */ 1574 ret = -ENODEV; 1575 goto error; 1576 } 1577 1578 pr_info("EC description table is found, configuring boot EC\n"); 1579 if (EC_FLAGS_CORRECT_ECDT) { 1580 /* 1581 * Asus L4R, Asus M6R 1582 * https://bugzilla.kernel.org/show_bug.cgi?id=9399 1583 * MSI MS-171F 1584 * https://bugzilla.kernel.org/show_bug.cgi?id=12461 1585 */ 1586 boot_ec->command_addr = ecdt_ptr->data.address; 1587 boot_ec->data_addr = ecdt_ptr->control.address; 1588 } else { 1589 boot_ec->command_addr = ecdt_ptr->control.address; 1590 boot_ec->data_addr = ecdt_ptr->data.address; 1591 } 1592 boot_ec->gpe = ecdt_ptr->gpe; 1593 boot_ec->handle = ACPI_ROOT_OBJECT; 1594 ret = ec_install_handlers(boot_ec); 1595 if (!ret) 1596 first_ec = boot_ec; 1597 error: 1598 if (ret) { 1599 kfree(boot_ec); 1600 boot_ec = NULL; 1601 } 1602 return ret; 1603 } 1604 1605 static int param_set_event_clearing(const char *val, struct kernel_param *kp) 1606 { 1607 int result = 0; 1608 1609 if (!strncmp(val, "status", sizeof("status") - 1)) { 1610 ec_event_clearing = ACPI_EC_EVT_TIMING_STATUS; 1611 pr_info("Assuming SCI_EVT clearing on EC_SC accesses\n"); 1612 } else if (!strncmp(val, "query", sizeof("query") - 1)) { 1613 ec_event_clearing = ACPI_EC_EVT_TIMING_QUERY; 1614 pr_info("Assuming SCI_EVT clearing on QR_EC writes\n"); 1615 } else if (!strncmp(val, "event", sizeof("event") - 1)) { 1616 ec_event_clearing = ACPI_EC_EVT_TIMING_EVENT; 1617 pr_info("Assuming SCI_EVT clearing on event reads\n"); 1618 } else 1619 result = -EINVAL; 1620 return result; 1621 } 1622 1623 static int param_get_event_clearing(char *buffer, struct kernel_param *kp) 1624 { 1625 switch (ec_event_clearing) { 1626 case ACPI_EC_EVT_TIMING_STATUS: 1627 return sprintf(buffer, "status"); 1628 case ACPI_EC_EVT_TIMING_QUERY: 1629 return sprintf(buffer, "query"); 1630 case ACPI_EC_EVT_TIMING_EVENT: 1631 return sprintf(buffer, "event"); 1632 default: 1633 return sprintf(buffer, "invalid"); 1634 } 1635 return 0; 1636 } 1637 1638 module_param_call(ec_event_clearing, param_set_event_clearing, param_get_event_clearing, 1639 NULL, 0644); 1640 MODULE_PARM_DESC(ec_event_clearing, "Assumed SCI_EVT clearing timing"); 1641 1642 static struct acpi_driver acpi_ec_driver = { 1643 .name = "ec", 1644 .class = ACPI_EC_CLASS, 1645 .ids = ec_device_ids, 1646 .ops = { 1647 .add = acpi_ec_add, 1648 .remove = acpi_ec_remove, 1649 }, 1650 }; 1651 1652 int __init acpi_ec_init(void) 1653 { 1654 int result = 0; 1655 1656 /* Now register the driver for the EC */ 1657 result = acpi_bus_register_driver(&acpi_ec_driver); 1658 if (result < 0) 1659 return -ENODEV; 1660 1661 return result; 1662 } 1663 1664 /* EC driver currently not unloadable */ 1665 #if 0 1666 static void __exit acpi_ec_exit(void) 1667 { 1668 1669 acpi_bus_unregister_driver(&acpi_ec_driver); 1670 } 1671 #endif /* 0 */ 1672