2 * ec.c - ACPI Embedded Controller Driver (v3)
4 * Copyright (C) 2001-2015 Intel Corporation
13 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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.
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.
25 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
28 /* Uncomment next line to get verbose printout */
30 #define pr_fmt(fmt) "ACPI: EC: " fmt
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>
47 #define ACPI_EC_CLASS "embedded_controller"
48 #define ACPI_EC_DEVICE_NAME "Embedded Controller"
49 #define ACPI_EC_FILE_INFO "info"
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 */
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
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
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.
86 #define ACPI_EC_EVT_TIMING_STATUS 0x00
87 #define ACPI_EC_EVT_TIMING_QUERY 0x01
88 #define ACPI_EC_EVT_TIMING_EVENT 0x02
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,
99 #define ACPI_EC_DELAY 500 /* Wait 500ms max. during EC ops */
100 #define ACPI_EC_UDELAY_GLK 1000 /* Wait 1ms max. to get global lock */
101 #define ACPI_EC_UDELAY_POLL 550 /* Wait 1ms for EC transaction polling */
102 #define ACPI_EC_CLEAR_MAX 100 /* Maximum number of events to query
103 * when trying to clear the EC */
104 #define ACPI_EC_MAX_QUERIES 16 /* Maximum number of parallel queries */
107 EC_FLAGS_QUERY_ENABLED, /* Query is enabled */
108 EC_FLAGS_QUERY_PENDING, /* Query is pending */
109 EC_FLAGS_QUERY_GUARDING, /* Guard for SCI_EVT check */
110 EC_FLAGS_GPE_HANDLER_INSTALLED, /* GPE handler installed */
111 EC_FLAGS_EC_HANDLER_INSTALLED, /* OpReg handler installed */
112 EC_FLAGS_EVT_HANDLER_INSTALLED, /* _Qxx handlers installed */
113 EC_FLAGS_STARTED, /* Driver is started */
114 EC_FLAGS_STOPPED, /* Driver is stopped */
115 EC_FLAGS_GPE_MASKED, /* GPE masked */
118 #define ACPI_EC_COMMAND_POLL 0x01 /* Available for command byte */
119 #define ACPI_EC_COMMAND_COMPLETE 0x02 /* Completed last byte */
121 /* ec.c is compiled in acpi namespace so this shows up as acpi.ec_delay param */
122 static unsigned int ec_delay __read_mostly = ACPI_EC_DELAY;
123 module_param(ec_delay, uint, 0644);
124 MODULE_PARM_DESC(ec_delay, "Timeout(ms) waited until an EC command completes");
126 static unsigned int ec_max_queries __read_mostly = ACPI_EC_MAX_QUERIES;
127 module_param(ec_max_queries, uint, 0644);
128 MODULE_PARM_DESC(ec_max_queries, "Maximum parallel _Qxx evaluations");
130 static bool ec_busy_polling __read_mostly;
131 module_param(ec_busy_polling, bool, 0644);
132 MODULE_PARM_DESC(ec_busy_polling, "Use busy polling to advance EC transaction");
134 static unsigned int ec_polling_guard __read_mostly = ACPI_EC_UDELAY_POLL;
135 module_param(ec_polling_guard, uint, 0644);
136 MODULE_PARM_DESC(ec_polling_guard, "Guard time(us) between EC accesses in polling modes");
138 static unsigned int ec_event_clearing __read_mostly = ACPI_EC_EVT_TIMING_QUERY;
141 * If the number of false interrupts per one transaction exceeds
142 * this threshold, will think there is a GPE storm happened and
143 * will disable the GPE for normal transaction.
145 static unsigned int ec_storm_threshold __read_mostly = 8;
146 module_param(ec_storm_threshold, uint, 0644);
147 MODULE_PARM_DESC(ec_storm_threshold, "Maxim false GPE numbers not considered as GPE storm");
149 static bool ec_freeze_events __read_mostly = false;
150 module_param(ec_freeze_events, bool, 0644);
151 MODULE_PARM_DESC(ec_freeze_events, "Disabling event handling during suspend/resume");
153 static bool ec_no_wakeup __read_mostly;
154 module_param(ec_no_wakeup, bool, 0644);
155 MODULE_PARM_DESC(ec_no_wakeup, "Do not wake up from suspend-to-idle");
157 struct acpi_ec_query_handler {
158 struct list_head node;
159 acpi_ec_query_func func;
169 unsigned short irq_count;
178 struct acpi_ec_query {
179 struct transaction transaction;
180 struct work_struct work;
181 struct acpi_ec_query_handler *handler;
184 static int acpi_ec_query(struct acpi_ec *ec, u8 *data);
185 static void advance_transaction(struct acpi_ec *ec);
186 static void acpi_ec_event_handler(struct work_struct *work);
187 static void acpi_ec_event_processor(struct work_struct *work);
189 struct acpi_ec *boot_ec, *first_ec;
190 EXPORT_SYMBOL(first_ec);
191 static bool boot_ec_is_ecdt = false;
192 static struct workqueue_struct *ec_query_wq;
194 static int EC_FLAGS_QUERY_HANDSHAKE; /* Needs QR_EC issued when SCI_EVT set */
195 static int EC_FLAGS_CORRECT_ECDT; /* Needs ECDT port address correction */
196 static int EC_FLAGS_IGNORE_DSDT_GPE; /* Needs ECDT GPE as correction setting */
198 /* --------------------------------------------------------------------------
200 * -------------------------------------------------------------------------- */
203 * Splitters used by the developers to track the boundary of the EC
204 * handling processes.
207 #define EC_DBG_SEP " "
208 #define EC_DBG_DRV "+++++"
209 #define EC_DBG_STM "====="
210 #define EC_DBG_REQ "*****"
211 #define EC_DBG_EVT "#####"
213 #define EC_DBG_SEP ""
220 #define ec_log_raw(fmt, ...) \
221 pr_info(fmt "\n", ##__VA_ARGS__)
222 #define ec_dbg_raw(fmt, ...) \
223 pr_debug(fmt "\n", ##__VA_ARGS__)
224 #define ec_log(filter, fmt, ...) \
225 ec_log_raw(filter EC_DBG_SEP fmt EC_DBG_SEP filter, ##__VA_ARGS__)
226 #define ec_dbg(filter, fmt, ...) \
227 ec_dbg_raw(filter EC_DBG_SEP fmt EC_DBG_SEP filter, ##__VA_ARGS__)
229 #define ec_log_drv(fmt, ...) \
230 ec_log(EC_DBG_DRV, fmt, ##__VA_ARGS__)
231 #define ec_dbg_drv(fmt, ...) \
232 ec_dbg(EC_DBG_DRV, fmt, ##__VA_ARGS__)
233 #define ec_dbg_stm(fmt, ...) \
234 ec_dbg(EC_DBG_STM, fmt, ##__VA_ARGS__)
235 #define ec_dbg_req(fmt, ...) \
236 ec_dbg(EC_DBG_REQ, fmt, ##__VA_ARGS__)
237 #define ec_dbg_evt(fmt, ...) \
238 ec_dbg(EC_DBG_EVT, fmt, ##__VA_ARGS__)
239 #define ec_dbg_ref(ec, fmt, ...) \
240 ec_dbg_raw("%lu: " fmt, ec->reference_count, ## __VA_ARGS__)
242 /* --------------------------------------------------------------------------
244 * -------------------------------------------------------------------------- */
246 static bool acpi_ec_started(struct acpi_ec *ec)
248 return test_bit(EC_FLAGS_STARTED, &ec->flags) &&
249 !test_bit(EC_FLAGS_STOPPED, &ec->flags);
252 static bool acpi_ec_event_enabled(struct acpi_ec *ec)
255 * There is an OSPM early stage logic. During the early stages
256 * (boot/resume), OSPMs shouldn't enable the event handling, only
257 * the EC transactions are allowed to be performed.
259 if (!test_bit(EC_FLAGS_QUERY_ENABLED, &ec->flags))
262 * However, disabling the event handling is experimental for late
263 * stage (suspend), and is controlled by the boot parameter of
264 * "ec_freeze_events":
265 * 1. true: The EC event handling is disabled before entering
267 * 2. false: The EC event handling is automatically disabled as
268 * soon as the EC driver is stopped.
270 if (ec_freeze_events)
271 return acpi_ec_started(ec);
273 return test_bit(EC_FLAGS_STARTED, &ec->flags);
276 static bool acpi_ec_flushed(struct acpi_ec *ec)
278 return ec->reference_count == 1;
281 /* --------------------------------------------------------------------------
283 * -------------------------------------------------------------------------- */
285 static inline u8 acpi_ec_read_status(struct acpi_ec *ec)
287 u8 x = inb(ec->command_addr);
289 ec_dbg_raw("EC_SC(R) = 0x%2.2x "
290 "SCI_EVT=%d BURST=%d CMD=%d IBF=%d OBF=%d",
292 !!(x & ACPI_EC_FLAG_SCI),
293 !!(x & ACPI_EC_FLAG_BURST),
294 !!(x & ACPI_EC_FLAG_CMD),
295 !!(x & ACPI_EC_FLAG_IBF),
296 !!(x & ACPI_EC_FLAG_OBF));
300 static inline u8 acpi_ec_read_data(struct acpi_ec *ec)
302 u8 x = inb(ec->data_addr);
304 ec->timestamp = jiffies;
305 ec_dbg_raw("EC_DATA(R) = 0x%2.2x", x);
309 static inline void acpi_ec_write_cmd(struct acpi_ec *ec, u8 command)
311 ec_dbg_raw("EC_SC(W) = 0x%2.2x", command);
312 outb(command, ec->command_addr);
313 ec->timestamp = jiffies;
316 static inline void acpi_ec_write_data(struct acpi_ec *ec, u8 data)
318 ec_dbg_raw("EC_DATA(W) = 0x%2.2x", data);
319 outb(data, ec->data_addr);
320 ec->timestamp = jiffies;
323 #if defined(DEBUG) || defined(CONFIG_DYNAMIC_DEBUG)
324 static const char *acpi_ec_cmd_string(u8 cmd)
341 #define acpi_ec_cmd_string(cmd) "UNDEF"
344 /* --------------------------------------------------------------------------
346 * -------------------------------------------------------------------------- */
348 static inline bool acpi_ec_is_gpe_raised(struct acpi_ec *ec)
350 acpi_event_status gpe_status = 0;
352 (void)acpi_get_gpe_status(NULL, ec->gpe, &gpe_status);
353 return (gpe_status & ACPI_EVENT_FLAG_STATUS_SET) ? true : false;
356 static inline void acpi_ec_enable_gpe(struct acpi_ec *ec, bool open)
359 acpi_enable_gpe(NULL, ec->gpe);
361 BUG_ON(ec->reference_count < 1);
362 acpi_set_gpe(NULL, ec->gpe, ACPI_GPE_ENABLE);
364 if (acpi_ec_is_gpe_raised(ec)) {
366 * On some platforms, EN=1 writes cannot trigger GPE. So
367 * software need to manually trigger a pseudo GPE event on
370 ec_dbg_raw("Polling quirk");
371 advance_transaction(ec);
375 static inline void acpi_ec_disable_gpe(struct acpi_ec *ec, bool close)
378 acpi_disable_gpe(NULL, ec->gpe);
380 BUG_ON(ec->reference_count < 1);
381 acpi_set_gpe(NULL, ec->gpe, ACPI_GPE_DISABLE);
385 static inline void acpi_ec_clear_gpe(struct acpi_ec *ec)
388 * GPE STS is a W1C register, which means:
389 * 1. Software can clear it without worrying about clearing other
390 * GPEs' STS bits when the hardware sets them in parallel.
391 * 2. As long as software can ensure only clearing it when it is
392 * set, hardware won't set it in parallel.
393 * So software can clear GPE in any contexts.
394 * Warning: do not move the check into advance_transaction() as the
395 * EC commands will be sent without GPE raised.
397 if (!acpi_ec_is_gpe_raised(ec))
399 acpi_clear_gpe(NULL, ec->gpe);
402 /* --------------------------------------------------------------------------
403 * Transaction Management
404 * -------------------------------------------------------------------------- */
406 static void acpi_ec_submit_request(struct acpi_ec *ec)
408 ec->reference_count++;
409 if (test_bit(EC_FLAGS_GPE_HANDLER_INSTALLED, &ec->flags) &&
410 ec->reference_count == 1)
411 acpi_ec_enable_gpe(ec, true);
414 static void acpi_ec_complete_request(struct acpi_ec *ec)
416 bool flushed = false;
418 ec->reference_count--;
419 if (test_bit(EC_FLAGS_GPE_HANDLER_INSTALLED, &ec->flags) &&
420 ec->reference_count == 0)
421 acpi_ec_disable_gpe(ec, true);
422 flushed = acpi_ec_flushed(ec);
427 static void acpi_ec_mask_gpe(struct acpi_ec *ec)
429 if (!test_bit(EC_FLAGS_GPE_MASKED, &ec->flags)) {
430 acpi_ec_disable_gpe(ec, false);
431 ec_dbg_drv("Polling enabled");
432 set_bit(EC_FLAGS_GPE_MASKED, &ec->flags);
436 static void acpi_ec_unmask_gpe(struct acpi_ec *ec)
438 if (test_bit(EC_FLAGS_GPE_MASKED, &ec->flags)) {
439 clear_bit(EC_FLAGS_GPE_MASKED, &ec->flags);
440 acpi_ec_enable_gpe(ec, false);
441 ec_dbg_drv("Polling disabled");
446 * acpi_ec_submit_flushable_request() - Increase the reference count unless
447 * the flush operation is not in
451 * This function must be used before taking a new action that should hold
452 * the reference count. If this function returns false, then the action
453 * must be discarded or it will prevent the flush operation from being
456 static bool acpi_ec_submit_flushable_request(struct acpi_ec *ec)
458 if (!acpi_ec_started(ec))
460 acpi_ec_submit_request(ec);
464 static void acpi_ec_submit_query(struct acpi_ec *ec)
466 acpi_ec_mask_gpe(ec);
467 if (!acpi_ec_event_enabled(ec))
469 if (!test_and_set_bit(EC_FLAGS_QUERY_PENDING, &ec->flags)) {
470 ec_dbg_evt("Command(%s) submitted/blocked",
471 acpi_ec_cmd_string(ACPI_EC_COMMAND_QUERY));
472 ec->nr_pending_queries++;
473 schedule_work(&ec->work);
477 static void acpi_ec_complete_query(struct acpi_ec *ec)
479 if (test_and_clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags))
480 ec_dbg_evt("Command(%s) unblocked",
481 acpi_ec_cmd_string(ACPI_EC_COMMAND_QUERY));
482 acpi_ec_unmask_gpe(ec);
485 static inline void __acpi_ec_enable_event(struct acpi_ec *ec)
487 if (!test_and_set_bit(EC_FLAGS_QUERY_ENABLED, &ec->flags))
488 ec_log_drv("event unblocked");
490 * Unconditionally invoke this once after enabling the event
491 * handling mechanism to detect the pending events.
493 advance_transaction(ec);
496 static inline void __acpi_ec_disable_event(struct acpi_ec *ec)
498 if (test_and_clear_bit(EC_FLAGS_QUERY_ENABLED, &ec->flags))
499 ec_log_drv("event blocked");
502 static void acpi_ec_enable_event(struct acpi_ec *ec)
506 spin_lock_irqsave(&ec->lock, flags);
507 if (acpi_ec_started(ec))
508 __acpi_ec_enable_event(ec);
509 spin_unlock_irqrestore(&ec->lock, flags);
512 #ifdef CONFIG_PM_SLEEP
513 static bool acpi_ec_query_flushed(struct acpi_ec *ec)
518 spin_lock_irqsave(&ec->lock, flags);
519 flushed = !ec->nr_pending_queries;
520 spin_unlock_irqrestore(&ec->lock, flags);
524 static void __acpi_ec_flush_event(struct acpi_ec *ec)
527 * When ec_freeze_events is true, we need to flush events in
528 * the proper position before entering the noirq stage.
530 wait_event(ec->wait, acpi_ec_query_flushed(ec));
532 flush_workqueue(ec_query_wq);
535 static void acpi_ec_disable_event(struct acpi_ec *ec)
539 spin_lock_irqsave(&ec->lock, flags);
540 __acpi_ec_disable_event(ec);
541 spin_unlock_irqrestore(&ec->lock, flags);
542 __acpi_ec_flush_event(ec);
545 void acpi_ec_flush_work(void)
548 __acpi_ec_flush_event(first_ec);
550 flush_scheduled_work();
552 #endif /* CONFIG_PM_SLEEP */
554 static bool acpi_ec_guard_event(struct acpi_ec *ec)
559 spin_lock_irqsave(&ec->lock, flags);
561 * If firmware SCI_EVT clearing timing is "event", we actually
562 * don't know when the SCI_EVT will be cleared by firmware after
563 * evaluating _Qxx, so we need to re-check SCI_EVT after waiting an
566 * The guarding period begins when EC_FLAGS_QUERY_PENDING is
567 * flagged, which means SCI_EVT check has just been performed.
568 * But if the current transaction is ACPI_EC_COMMAND_QUERY, the
569 * guarding should have already been performed (via
570 * EC_FLAGS_QUERY_GUARDING) and should not be applied so that the
571 * ACPI_EC_COMMAND_QUERY transaction can be transitioned into
572 * ACPI_EC_COMMAND_POLL state immediately.
574 if (ec_event_clearing == ACPI_EC_EVT_TIMING_STATUS ||
575 ec_event_clearing == ACPI_EC_EVT_TIMING_QUERY ||
576 !test_bit(EC_FLAGS_QUERY_PENDING, &ec->flags) ||
577 (ec->curr && ec->curr->command == ACPI_EC_COMMAND_QUERY))
579 spin_unlock_irqrestore(&ec->lock, flags);
583 static int ec_transaction_polled(struct acpi_ec *ec)
588 spin_lock_irqsave(&ec->lock, flags);
589 if (ec->curr && (ec->curr->flags & ACPI_EC_COMMAND_POLL))
591 spin_unlock_irqrestore(&ec->lock, flags);
595 static int ec_transaction_completed(struct acpi_ec *ec)
600 spin_lock_irqsave(&ec->lock, flags);
601 if (ec->curr && (ec->curr->flags & ACPI_EC_COMMAND_COMPLETE))
603 spin_unlock_irqrestore(&ec->lock, flags);
607 static inline void ec_transaction_transition(struct acpi_ec *ec, unsigned long flag)
609 ec->curr->flags |= flag;
610 if (ec->curr->command == ACPI_EC_COMMAND_QUERY) {
611 if (ec_event_clearing == ACPI_EC_EVT_TIMING_STATUS &&
612 flag == ACPI_EC_COMMAND_POLL)
613 acpi_ec_complete_query(ec);
614 if (ec_event_clearing == ACPI_EC_EVT_TIMING_QUERY &&
615 flag == ACPI_EC_COMMAND_COMPLETE)
616 acpi_ec_complete_query(ec);
617 if (ec_event_clearing == ACPI_EC_EVT_TIMING_EVENT &&
618 flag == ACPI_EC_COMMAND_COMPLETE)
619 set_bit(EC_FLAGS_QUERY_GUARDING, &ec->flags);
623 static void advance_transaction(struct acpi_ec *ec)
625 struct transaction *t;
629 ec_dbg_stm("%s (%d)", in_interrupt() ? "IRQ" : "TASK",
632 * By always clearing STS before handling all indications, we can
633 * ensure a hardware STS 0->1 change after this clearing can always
634 * trigger a GPE interrupt.
636 acpi_ec_clear_gpe(ec);
637 status = acpi_ec_read_status(ec);
640 * Another IRQ or a guarded polling mode advancement is detected,
641 * the next QR_EC submission is then allowed.
643 if (!t || !(t->flags & ACPI_EC_COMMAND_POLL)) {
644 if (ec_event_clearing == ACPI_EC_EVT_TIMING_EVENT &&
645 (!ec->nr_pending_queries ||
646 test_bit(EC_FLAGS_QUERY_GUARDING, &ec->flags))) {
647 clear_bit(EC_FLAGS_QUERY_GUARDING, &ec->flags);
648 acpi_ec_complete_query(ec);
653 if (t->flags & ACPI_EC_COMMAND_POLL) {
654 if (t->wlen > t->wi) {
655 if ((status & ACPI_EC_FLAG_IBF) == 0)
656 acpi_ec_write_data(ec, t->wdata[t->wi++]);
659 } else if (t->rlen > t->ri) {
660 if ((status & ACPI_EC_FLAG_OBF) == 1) {
661 t->rdata[t->ri++] = acpi_ec_read_data(ec);
662 if (t->rlen == t->ri) {
663 ec_transaction_transition(ec, ACPI_EC_COMMAND_COMPLETE);
664 if (t->command == ACPI_EC_COMMAND_QUERY)
665 ec_dbg_evt("Command(%s) completed by hardware",
666 acpi_ec_cmd_string(ACPI_EC_COMMAND_QUERY));
671 } else if (t->wlen == t->wi &&
672 (status & ACPI_EC_FLAG_IBF) == 0) {
673 ec_transaction_transition(ec, ACPI_EC_COMMAND_COMPLETE);
678 if (EC_FLAGS_QUERY_HANDSHAKE &&
679 !(status & ACPI_EC_FLAG_SCI) &&
680 (t->command == ACPI_EC_COMMAND_QUERY)) {
681 ec_transaction_transition(ec, ACPI_EC_COMMAND_POLL);
682 t->rdata[t->ri++] = 0x00;
683 ec_transaction_transition(ec, ACPI_EC_COMMAND_COMPLETE);
684 ec_dbg_evt("Command(%s) completed by software",
685 acpi_ec_cmd_string(ACPI_EC_COMMAND_QUERY));
687 } else if ((status & ACPI_EC_FLAG_IBF) == 0) {
688 acpi_ec_write_cmd(ec, t->command);
689 ec_transaction_transition(ec, ACPI_EC_COMMAND_POLL);
696 * If SCI bit is set, then don't think it's a false IRQ
697 * otherwise will take a not handled IRQ as a false one.
699 if (!(status & ACPI_EC_FLAG_SCI)) {
700 if (in_interrupt() && t) {
701 if (t->irq_count < ec_storm_threshold)
703 /* Allow triggering on 0 threshold */
704 if (t->irq_count == ec_storm_threshold)
705 acpi_ec_mask_gpe(ec);
709 if (status & ACPI_EC_FLAG_SCI)
710 acpi_ec_submit_query(ec);
711 if (wakeup && in_interrupt())
715 static void start_transaction(struct acpi_ec *ec)
717 ec->curr->irq_count = ec->curr->wi = ec->curr->ri = 0;
721 static int ec_guard(struct acpi_ec *ec)
723 unsigned long guard = usecs_to_jiffies(ec->polling_guard);
724 unsigned long timeout = ec->timestamp + guard;
726 /* Ensure guarding period before polling EC status */
728 if (ec->busy_polling) {
729 /* Perform busy polling */
730 if (ec_transaction_completed(ec))
732 udelay(jiffies_to_usecs(guard));
735 * Perform wait polling
736 * 1. Wait the transaction to be completed by the
737 * GPE handler after the transaction enters
738 * ACPI_EC_COMMAND_POLL state.
739 * 2. A special guarding logic is also required
740 * for event clearing mode "event" before the
741 * transaction enters ACPI_EC_COMMAND_POLL
744 if (!ec_transaction_polled(ec) &&
745 !acpi_ec_guard_event(ec))
747 if (wait_event_timeout(ec->wait,
748 ec_transaction_completed(ec),
752 } while (time_before(jiffies, timeout));
756 static int ec_poll(struct acpi_ec *ec)
759 int repeat = 5; /* number of command restarts */
762 unsigned long delay = jiffies +
763 msecs_to_jiffies(ec_delay);
767 spin_lock_irqsave(&ec->lock, flags);
768 advance_transaction(ec);
769 spin_unlock_irqrestore(&ec->lock, flags);
770 } while (time_before(jiffies, delay));
771 pr_debug("controller reset, restart transaction\n");
772 spin_lock_irqsave(&ec->lock, flags);
773 start_transaction(ec);
774 spin_unlock_irqrestore(&ec->lock, flags);
779 static int acpi_ec_transaction_unlocked(struct acpi_ec *ec,
780 struct transaction *t)
785 /* start transaction */
786 spin_lock_irqsave(&ec->lock, tmp);
787 /* Enable GPE for command processing (IBF=0/OBF=1) */
788 if (!acpi_ec_submit_flushable_request(ec)) {
792 ec_dbg_ref(ec, "Increase command");
793 /* following two actions should be kept atomic */
795 ec_dbg_req("Command(%s) started", acpi_ec_cmd_string(t->command));
796 start_transaction(ec);
797 spin_unlock_irqrestore(&ec->lock, tmp);
801 spin_lock_irqsave(&ec->lock, tmp);
802 if (t->irq_count == ec_storm_threshold)
803 acpi_ec_unmask_gpe(ec);
804 ec_dbg_req("Command(%s) stopped", acpi_ec_cmd_string(t->command));
806 /* Disable GPE for command processing (IBF=0/OBF=1) */
807 acpi_ec_complete_request(ec);
808 ec_dbg_ref(ec, "Decrease command");
810 spin_unlock_irqrestore(&ec->lock, tmp);
814 static int acpi_ec_transaction(struct acpi_ec *ec, struct transaction *t)
819 if (!ec || (!t) || (t->wlen && !t->wdata) || (t->rlen && !t->rdata))
822 memset(t->rdata, 0, t->rlen);
824 mutex_lock(&ec->mutex);
825 if (ec->global_lock) {
826 status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk);
827 if (ACPI_FAILURE(status)) {
833 status = acpi_ec_transaction_unlocked(ec, t);
836 acpi_release_global_lock(glk);
838 mutex_unlock(&ec->mutex);
842 static int acpi_ec_burst_enable(struct acpi_ec *ec)
845 struct transaction t = {.command = ACPI_EC_BURST_ENABLE,
846 .wdata = NULL, .rdata = &d,
847 .wlen = 0, .rlen = 1};
849 return acpi_ec_transaction(ec, &t);
852 static int acpi_ec_burst_disable(struct acpi_ec *ec)
854 struct transaction t = {.command = ACPI_EC_BURST_DISABLE,
855 .wdata = NULL, .rdata = NULL,
856 .wlen = 0, .rlen = 0};
858 return (acpi_ec_read_status(ec) & ACPI_EC_FLAG_BURST) ?
859 acpi_ec_transaction(ec, &t) : 0;
862 static int acpi_ec_read(struct acpi_ec *ec, u8 address, u8 *data)
866 struct transaction t = {.command = ACPI_EC_COMMAND_READ,
867 .wdata = &address, .rdata = &d,
868 .wlen = 1, .rlen = 1};
870 result = acpi_ec_transaction(ec, &t);
875 static int acpi_ec_write(struct acpi_ec *ec, u8 address, u8 data)
877 u8 wdata[2] = { address, data };
878 struct transaction t = {.command = ACPI_EC_COMMAND_WRITE,
879 .wdata = wdata, .rdata = NULL,
880 .wlen = 2, .rlen = 0};
882 return acpi_ec_transaction(ec, &t);
885 int ec_read(u8 addr, u8 *val)
893 err = acpi_ec_read(first_ec, addr, &temp_data);
901 EXPORT_SYMBOL(ec_read);
903 int ec_write(u8 addr, u8 val)
910 err = acpi_ec_write(first_ec, addr, val);
914 EXPORT_SYMBOL(ec_write);
916 int ec_transaction(u8 command,
917 const u8 *wdata, unsigned wdata_len,
918 u8 *rdata, unsigned rdata_len)
920 struct transaction t = {.command = command,
921 .wdata = wdata, .rdata = rdata,
922 .wlen = wdata_len, .rlen = rdata_len};
927 return acpi_ec_transaction(first_ec, &t);
929 EXPORT_SYMBOL(ec_transaction);
931 /* Get the handle to the EC device */
932 acpi_handle ec_get_handle(void)
936 return first_ec->handle;
938 EXPORT_SYMBOL(ec_get_handle);
940 static void acpi_ec_start(struct acpi_ec *ec, bool resuming)
944 spin_lock_irqsave(&ec->lock, flags);
945 if (!test_and_set_bit(EC_FLAGS_STARTED, &ec->flags)) {
946 ec_dbg_drv("Starting EC");
947 /* Enable GPE for event processing (SCI_EVT=1) */
949 acpi_ec_submit_request(ec);
950 ec_dbg_ref(ec, "Increase driver");
952 ec_log_drv("EC started");
954 spin_unlock_irqrestore(&ec->lock, flags);
957 static bool acpi_ec_stopped(struct acpi_ec *ec)
962 spin_lock_irqsave(&ec->lock, flags);
963 flushed = acpi_ec_flushed(ec);
964 spin_unlock_irqrestore(&ec->lock, flags);
968 static void acpi_ec_stop(struct acpi_ec *ec, bool suspending)
972 spin_lock_irqsave(&ec->lock, flags);
973 if (acpi_ec_started(ec)) {
974 ec_dbg_drv("Stopping EC");
975 set_bit(EC_FLAGS_STOPPED, &ec->flags);
976 spin_unlock_irqrestore(&ec->lock, flags);
977 wait_event(ec->wait, acpi_ec_stopped(ec));
978 spin_lock_irqsave(&ec->lock, flags);
979 /* Disable GPE for event processing (SCI_EVT=1) */
981 acpi_ec_complete_request(ec);
982 ec_dbg_ref(ec, "Decrease driver");
983 } else if (!ec_freeze_events)
984 __acpi_ec_disable_event(ec);
985 clear_bit(EC_FLAGS_STARTED, &ec->flags);
986 clear_bit(EC_FLAGS_STOPPED, &ec->flags);
987 ec_log_drv("EC stopped");
989 spin_unlock_irqrestore(&ec->lock, flags);
992 static void acpi_ec_enter_noirq(struct acpi_ec *ec)
996 spin_lock_irqsave(&ec->lock, flags);
997 ec->busy_polling = true;
998 ec->polling_guard = 0;
999 ec_log_drv("interrupt blocked");
1000 spin_unlock_irqrestore(&ec->lock, flags);
1003 static void acpi_ec_leave_noirq(struct acpi_ec *ec)
1005 unsigned long flags;
1007 spin_lock_irqsave(&ec->lock, flags);
1008 ec->busy_polling = ec_busy_polling;
1009 ec->polling_guard = ec_polling_guard;
1010 ec_log_drv("interrupt unblocked");
1011 spin_unlock_irqrestore(&ec->lock, flags);
1014 void acpi_ec_block_transactions(void)
1016 struct acpi_ec *ec = first_ec;
1021 mutex_lock(&ec->mutex);
1022 /* Prevent transactions from being carried out */
1023 acpi_ec_stop(ec, true);
1024 mutex_unlock(&ec->mutex);
1027 void acpi_ec_unblock_transactions(void)
1030 * Allow transactions to happen again (this function is called from
1031 * atomic context during wakeup, so we don't need to acquire the mutex).
1034 acpi_ec_start(first_ec, true);
1037 void acpi_ec_dispatch_gpe(void)
1040 acpi_dispatch_gpe(NULL, first_ec->gpe);
1043 /* --------------------------------------------------------------------------
1045 -------------------------------------------------------------------------- */
1046 static struct acpi_ec_query_handler *
1047 acpi_ec_get_query_handler(struct acpi_ec_query_handler *handler)
1050 kref_get(&handler->kref);
1054 static struct acpi_ec_query_handler *
1055 acpi_ec_get_query_handler_by_value(struct acpi_ec *ec, u8 value)
1057 struct acpi_ec_query_handler *handler;
1060 mutex_lock(&ec->mutex);
1061 list_for_each_entry(handler, &ec->list, node) {
1062 if (value == handler->query_bit) {
1067 mutex_unlock(&ec->mutex);
1068 return found ? acpi_ec_get_query_handler(handler) : NULL;
1071 static void acpi_ec_query_handler_release(struct kref *kref)
1073 struct acpi_ec_query_handler *handler =
1074 container_of(kref, struct acpi_ec_query_handler, kref);
1079 static void acpi_ec_put_query_handler(struct acpi_ec_query_handler *handler)
1081 kref_put(&handler->kref, acpi_ec_query_handler_release);
1084 int acpi_ec_add_query_handler(struct acpi_ec *ec, u8 query_bit,
1085 acpi_handle handle, acpi_ec_query_func func,
1088 struct acpi_ec_query_handler *handler =
1089 kzalloc(sizeof(struct acpi_ec_query_handler), GFP_KERNEL);
1094 handler->query_bit = query_bit;
1095 handler->handle = handle;
1096 handler->func = func;
1097 handler->data = data;
1098 mutex_lock(&ec->mutex);
1099 kref_init(&handler->kref);
1100 list_add(&handler->node, &ec->list);
1101 mutex_unlock(&ec->mutex);
1104 EXPORT_SYMBOL_GPL(acpi_ec_add_query_handler);
1106 static void acpi_ec_remove_query_handlers(struct acpi_ec *ec,
1107 bool remove_all, u8 query_bit)
1109 struct acpi_ec_query_handler *handler, *tmp;
1110 LIST_HEAD(free_list);
1112 mutex_lock(&ec->mutex);
1113 list_for_each_entry_safe(handler, tmp, &ec->list, node) {
1114 if (remove_all || query_bit == handler->query_bit) {
1115 list_del_init(&handler->node);
1116 list_add(&handler->node, &free_list);
1119 mutex_unlock(&ec->mutex);
1120 list_for_each_entry_safe(handler, tmp, &free_list, node)
1121 acpi_ec_put_query_handler(handler);
1124 void acpi_ec_remove_query_handler(struct acpi_ec *ec, u8 query_bit)
1126 acpi_ec_remove_query_handlers(ec, false, query_bit);
1128 EXPORT_SYMBOL_GPL(acpi_ec_remove_query_handler);
1130 static struct acpi_ec_query *acpi_ec_create_query(u8 *pval)
1132 struct acpi_ec_query *q;
1133 struct transaction *t;
1135 q = kzalloc(sizeof (struct acpi_ec_query), GFP_KERNEL);
1138 INIT_WORK(&q->work, acpi_ec_event_processor);
1139 t = &q->transaction;
1140 t->command = ACPI_EC_COMMAND_QUERY;
1146 static void acpi_ec_delete_query(struct acpi_ec_query *q)
1150 acpi_ec_put_query_handler(q->handler);
1155 static void acpi_ec_event_processor(struct work_struct *work)
1157 struct acpi_ec_query *q = container_of(work, struct acpi_ec_query, work);
1158 struct acpi_ec_query_handler *handler = q->handler;
1160 ec_dbg_evt("Query(0x%02x) started", handler->query_bit);
1162 handler->func(handler->data);
1163 else if (handler->handle)
1164 acpi_evaluate_object(handler->handle, NULL, NULL, NULL);
1165 ec_dbg_evt("Query(0x%02x) stopped", handler->query_bit);
1166 acpi_ec_delete_query(q);
1169 static int acpi_ec_query(struct acpi_ec *ec, u8 *data)
1173 struct acpi_ec_query *q;
1175 q = acpi_ec_create_query(&value);
1180 * Query the EC to find out which _Qxx method we need to evaluate.
1181 * Note that successful completion of the query causes the ACPI_EC_SCI
1182 * bit to be cleared (and thus clearing the interrupt source).
1184 result = acpi_ec_transaction(ec, &q->transaction);
1190 q->handler = acpi_ec_get_query_handler_by_value(ec, value);
1197 * It is reported that _Qxx are evaluated in a parallel way on
1199 * https://bugzilla.kernel.org/show_bug.cgi?id=94411
1201 * Put this log entry before schedule_work() in order to make
1202 * it appearing before any other log entries occurred during the
1203 * work queue execution.
1205 ec_dbg_evt("Query(0x%02x) scheduled", value);
1206 if (!queue_work(ec_query_wq, &q->work)) {
1207 ec_dbg_evt("Query(0x%02x) overlapped", value);
1213 acpi_ec_delete_query(q);
1219 static void acpi_ec_check_event(struct acpi_ec *ec)
1221 unsigned long flags;
1223 if (ec_event_clearing == ACPI_EC_EVT_TIMING_EVENT) {
1225 spin_lock_irqsave(&ec->lock, flags);
1227 * Take care of the SCI_EVT unless no one else is
1228 * taking care of it.
1231 advance_transaction(ec);
1232 spin_unlock_irqrestore(&ec->lock, flags);
1237 static void acpi_ec_event_handler(struct work_struct *work)
1239 unsigned long flags;
1240 struct acpi_ec *ec = container_of(work, struct acpi_ec, work);
1242 ec_dbg_evt("Event started");
1244 spin_lock_irqsave(&ec->lock, flags);
1245 while (ec->nr_pending_queries) {
1246 spin_unlock_irqrestore(&ec->lock, flags);
1247 (void)acpi_ec_query(ec, NULL);
1248 spin_lock_irqsave(&ec->lock, flags);
1249 ec->nr_pending_queries--;
1251 * Before exit, make sure that this work item can be
1252 * scheduled again. There might be QR_EC failures, leaving
1253 * EC_FLAGS_QUERY_PENDING uncleared and preventing this work
1254 * item from being scheduled again.
1256 if (!ec->nr_pending_queries) {
1257 if (ec_event_clearing == ACPI_EC_EVT_TIMING_STATUS ||
1258 ec_event_clearing == ACPI_EC_EVT_TIMING_QUERY)
1259 acpi_ec_complete_query(ec);
1262 spin_unlock_irqrestore(&ec->lock, flags);
1264 ec_dbg_evt("Event stopped");
1266 acpi_ec_check_event(ec);
1269 static u32 acpi_ec_gpe_handler(acpi_handle gpe_device,
1270 u32 gpe_number, void *data)
1272 unsigned long flags;
1273 struct acpi_ec *ec = data;
1275 spin_lock_irqsave(&ec->lock, flags);
1276 advance_transaction(ec);
1277 spin_unlock_irqrestore(&ec->lock, flags);
1278 return ACPI_INTERRUPT_HANDLED;
1281 /* --------------------------------------------------------------------------
1282 * Address Space Management
1283 * -------------------------------------------------------------------------- */
1286 acpi_ec_space_handler(u32 function, acpi_physical_address address,
1287 u32 bits, u64 *value64,
1288 void *handler_context, void *region_context)
1290 struct acpi_ec *ec = handler_context;
1291 int result = 0, i, bytes = bits / 8;
1292 u8 *value = (u8 *)value64;
1294 if ((address > 0xFF) || !value || !handler_context)
1295 return AE_BAD_PARAMETER;
1297 if (function != ACPI_READ && function != ACPI_WRITE)
1298 return AE_BAD_PARAMETER;
1300 if (ec->busy_polling || bits > 8)
1301 acpi_ec_burst_enable(ec);
1303 for (i = 0; i < bytes; ++i, ++address, ++value)
1304 result = (function == ACPI_READ) ?
1305 acpi_ec_read(ec, address, value) :
1306 acpi_ec_write(ec, address, *value);
1308 if (ec->busy_polling || bits > 8)
1309 acpi_ec_burst_disable(ec);
1313 return AE_BAD_PARAMETER;
1315 return AE_NOT_FOUND;
1323 /* --------------------------------------------------------------------------
1325 * -------------------------------------------------------------------------- */
1328 ec_parse_io_ports(struct acpi_resource *resource, void *context);
1330 static void acpi_ec_free(struct acpi_ec *ec)
1339 static struct acpi_ec *acpi_ec_alloc(void)
1341 struct acpi_ec *ec = kzalloc(sizeof(struct acpi_ec), GFP_KERNEL);
1345 mutex_init(&ec->mutex);
1346 init_waitqueue_head(&ec->wait);
1347 INIT_LIST_HEAD(&ec->list);
1348 spin_lock_init(&ec->lock);
1349 INIT_WORK(&ec->work, acpi_ec_event_handler);
1350 ec->timestamp = jiffies;
1351 ec->busy_polling = true;
1352 ec->polling_guard = 0;
1357 acpi_ec_register_query_methods(acpi_handle handle, u32 level,
1358 void *context, void **return_value)
1361 struct acpi_buffer buffer = { sizeof(node_name), node_name };
1362 struct acpi_ec *ec = context;
1366 status = acpi_get_name(handle, ACPI_SINGLE_NAME, &buffer);
1368 if (ACPI_SUCCESS(status) && sscanf(node_name, "_Q%x", &value) == 1)
1369 acpi_ec_add_query_handler(ec, value, handle, NULL, NULL);
1374 ec_parse_device(acpi_handle handle, u32 Level, void *context, void **retval)
1377 unsigned long long tmp = 0;
1378 struct acpi_ec *ec = context;
1380 /* clear addr values, ec_parse_io_ports depend on it */
1381 ec->command_addr = ec->data_addr = 0;
1383 status = acpi_walk_resources(handle, METHOD_NAME__CRS,
1384 ec_parse_io_ports, ec);
1385 if (ACPI_FAILURE(status))
1387 if (ec->data_addr == 0 || ec->command_addr == 0)
1390 if (boot_ec && boot_ec_is_ecdt && EC_FLAGS_IGNORE_DSDT_GPE) {
1392 * Always inherit the GPE number setting from the ECDT
1395 ec->gpe = boot_ec->gpe;
1397 /* Get GPE bit assignment (EC events). */
1398 /* TODO: Add support for _GPE returning a package */
1399 status = acpi_evaluate_integer(handle, "_GPE", NULL, &tmp);
1400 if (ACPI_FAILURE(status))
1404 /* Use the global lock for all EC transactions? */
1406 acpi_evaluate_integer(handle, "_GLK", NULL, &tmp);
1407 ec->global_lock = tmp;
1408 ec->handle = handle;
1409 return AE_CTRL_TERMINATE;
1413 * Note: This function returns an error code only when the address space
1414 * handler is not installed, which means "not able to handle
1417 static int ec_install_handlers(struct acpi_ec *ec, bool handle_events)
1421 acpi_ec_start(ec, false);
1423 if (!test_bit(EC_FLAGS_EC_HANDLER_INSTALLED, &ec->flags)) {
1424 acpi_ec_enter_noirq(ec);
1425 status = acpi_install_address_space_handler(ec->handle,
1427 &acpi_ec_space_handler,
1429 if (ACPI_FAILURE(status)) {
1430 if (status == AE_NOT_FOUND) {
1432 * Maybe OS fails in evaluating the _REG
1433 * object. The AE_NOT_FOUND error will be
1434 * ignored and OS * continue to initialize
1437 pr_err("Fail in evaluating the _REG object"
1438 " of EC device. Broken bios is suspected.\n");
1440 acpi_ec_stop(ec, false);
1444 set_bit(EC_FLAGS_EC_HANDLER_INSTALLED, &ec->flags);
1450 if (!test_bit(EC_FLAGS_EVT_HANDLER_INSTALLED, &ec->flags)) {
1451 /* Find and register all query methods */
1452 acpi_walk_namespace(ACPI_TYPE_METHOD, ec->handle, 1,
1453 acpi_ec_register_query_methods,
1455 set_bit(EC_FLAGS_EVT_HANDLER_INSTALLED, &ec->flags);
1457 if (!test_bit(EC_FLAGS_GPE_HANDLER_INSTALLED, &ec->flags)) {
1458 status = acpi_install_gpe_raw_handler(NULL, ec->gpe,
1459 ACPI_GPE_EDGE_TRIGGERED,
1460 &acpi_ec_gpe_handler, ec);
1461 /* This is not fatal as we can poll EC events */
1462 if (ACPI_SUCCESS(status)) {
1463 set_bit(EC_FLAGS_GPE_HANDLER_INSTALLED, &ec->flags);
1464 acpi_ec_leave_noirq(ec);
1465 if (test_bit(EC_FLAGS_STARTED, &ec->flags) &&
1466 ec->reference_count >= 1)
1467 acpi_ec_enable_gpe(ec, true);
1470 /* EC is fully operational, allow queries */
1471 acpi_ec_enable_event(ec);
1476 static void ec_remove_handlers(struct acpi_ec *ec)
1478 if (test_bit(EC_FLAGS_EC_HANDLER_INSTALLED, &ec->flags)) {
1479 if (ACPI_FAILURE(acpi_remove_address_space_handler(ec->handle,
1480 ACPI_ADR_SPACE_EC, &acpi_ec_space_handler)))
1481 pr_err("failed to remove space handler\n");
1482 clear_bit(EC_FLAGS_EC_HANDLER_INSTALLED, &ec->flags);
1486 * Stops handling the EC transactions after removing the operation
1487 * region handler. This is required because _REG(DISCONNECT)
1488 * invoked during the removal can result in new EC transactions.
1490 * Flushes the EC requests and thus disables the GPE before
1491 * removing the GPE handler. This is required by the current ACPICA
1492 * GPE core. ACPICA GPE core will automatically disable a GPE when
1493 * it is indicated but there is no way to handle it. So the drivers
1494 * must disable the GPEs prior to removing the GPE handlers.
1496 acpi_ec_stop(ec, false);
1498 if (test_bit(EC_FLAGS_GPE_HANDLER_INSTALLED, &ec->flags)) {
1499 if (ACPI_FAILURE(acpi_remove_gpe_handler(NULL, ec->gpe,
1500 &acpi_ec_gpe_handler)))
1501 pr_err("failed to remove gpe handler\n");
1502 clear_bit(EC_FLAGS_GPE_HANDLER_INSTALLED, &ec->flags);
1504 if (test_bit(EC_FLAGS_EVT_HANDLER_INSTALLED, &ec->flags)) {
1505 acpi_ec_remove_query_handlers(ec, true, 0);
1506 clear_bit(EC_FLAGS_EVT_HANDLER_INSTALLED, &ec->flags);
1510 static int acpi_ec_setup(struct acpi_ec *ec, bool handle_events)
1514 ret = ec_install_handlers(ec, handle_events);
1518 /* First EC capable of handling transactions */
1521 acpi_handle_info(first_ec->handle, "Used as first EC\n");
1524 acpi_handle_info(ec->handle,
1525 "GPE=0x%x, EC_CMD/EC_SC=0x%lx, EC_DATA=0x%lx\n",
1526 ec->gpe, ec->command_addr, ec->data_addr);
1530 static int acpi_config_boot_ec(struct acpi_ec *ec, acpi_handle handle,
1531 bool handle_events, bool is_ecdt)
1536 * Changing the ACPI handle results in a re-configuration of the
1537 * boot EC. And if it happens after the namespace initialization,
1538 * it causes _REG evaluations.
1540 if (boot_ec && boot_ec->handle != handle)
1541 ec_remove_handlers(boot_ec);
1543 /* Unset old boot EC */
1545 acpi_ec_free(boot_ec);
1548 * ECDT device creation is split into acpi_ec_ecdt_probe() and
1549 * acpi_ec_ecdt_start(). This function takes care of completing the
1550 * ECDT parsing logic as the handle update should be performed
1551 * between the installation/uninstallation of the handlers.
1553 if (ec->handle != handle)
1554 ec->handle = handle;
1556 ret = acpi_ec_setup(ec, handle_events);
1560 /* Set new boot EC */
1563 boot_ec_is_ecdt = is_ecdt;
1566 acpi_handle_info(boot_ec->handle,
1567 "Used as boot %s EC to handle transactions%s\n",
1568 is_ecdt ? "ECDT" : "DSDT",
1569 handle_events ? " and events" : "");
1573 static bool acpi_ec_ecdt_get_handle(acpi_handle *phandle)
1575 struct acpi_table_ecdt *ecdt_ptr;
1579 status = acpi_get_table(ACPI_SIG_ECDT, 1,
1580 (struct acpi_table_header **)&ecdt_ptr);
1581 if (ACPI_FAILURE(status))
1584 status = acpi_get_handle(NULL, ecdt_ptr->id, &handle);
1585 if (ACPI_FAILURE(status))
1592 static bool acpi_is_boot_ec(struct acpi_ec *ec)
1596 if (ec->command_addr == boot_ec->command_addr &&
1597 ec->data_addr == boot_ec->data_addr)
1602 static int acpi_ec_add(struct acpi_device *device)
1604 struct acpi_ec *ec = NULL;
1606 bool is_ecdt = false;
1609 strcpy(acpi_device_name(device), ACPI_EC_DEVICE_NAME);
1610 strcpy(acpi_device_class(device), ACPI_EC_CLASS);
1612 if (!strcmp(acpi_device_hid(device), ACPI_ECDT_HID)) {
1616 ec = acpi_ec_alloc();
1619 status = ec_parse_device(device->handle, 0, ec, NULL);
1620 if (status != AE_CTRL_TERMINATE) {
1626 if (acpi_is_boot_ec(ec)) {
1627 boot_ec_is_ecdt = is_ecdt;
1630 * Trust PNP0C09 namespace location rather than
1631 * ECDT ID. But trust ECDT GPE rather than _GPE
1632 * because of ASUS quirks, so do not change
1633 * boot_ec->gpe to ec->gpe.
1635 boot_ec->handle = ec->handle;
1636 acpi_handle_debug(ec->handle, "duplicated.\n");
1640 ret = acpi_config_boot_ec(ec, ec->handle, true, is_ecdt);
1642 ret = acpi_ec_setup(ec, true);
1646 device->driver_data = ec;
1648 ret = !!request_region(ec->data_addr, 1, "EC data");
1649 WARN(!ret, "Could not request EC data io port 0x%lx", ec->data_addr);
1650 ret = !!request_region(ec->command_addr, 1, "EC cmd");
1651 WARN(!ret, "Could not request EC cmd io port 0x%lx", ec->command_addr);
1654 /* Reprobe devices depending on the EC */
1655 acpi_walk_dep_device_list(ec->handle);
1657 acpi_handle_debug(ec->handle, "enumerated.\n");
1662 acpi_ec_remove_query_handlers(ec, true, 0);
1669 static int acpi_ec_remove(struct acpi_device *device)
1676 ec = acpi_driver_data(device);
1677 release_region(ec->data_addr, 1);
1678 release_region(ec->command_addr, 1);
1679 device->driver_data = NULL;
1680 if (ec != boot_ec) {
1681 ec_remove_handlers(ec);
1688 ec_parse_io_ports(struct acpi_resource *resource, void *context)
1690 struct acpi_ec *ec = context;
1692 if (resource->type != ACPI_RESOURCE_TYPE_IO)
1696 * The first address region returned is the data port, and
1697 * the second address region returned is the status/command
1700 if (ec->data_addr == 0)
1701 ec->data_addr = resource->data.io.minimum;
1702 else if (ec->command_addr == 0)
1703 ec->command_addr = resource->data.io.minimum;
1705 return AE_CTRL_TERMINATE;
1710 static const struct acpi_device_id ec_device_ids[] = {
1717 * This function is not Windows-compatible as Windows never enumerates the
1718 * namespace EC before the main ACPI device enumeration process. It is
1719 * retained for historical reason and will be deprecated in the future.
1721 int __init acpi_ec_dsdt_probe(void)
1728 * If a platform has ECDT, there is no need to proceed as the
1729 * following probe is not a part of the ACPI device enumeration,
1730 * executing _STA is not safe, and thus this probe may risk of
1731 * picking up an invalid EC device.
1736 ec = acpi_ec_alloc();
1740 * At this point, the namespace is initialized, so start to find
1741 * the namespace objects.
1743 status = acpi_get_devices(ec_device_ids[0].id,
1744 ec_parse_device, ec, NULL);
1745 if (ACPI_FAILURE(status) || !ec->handle) {
1750 * When the DSDT EC is available, always re-configure boot EC to
1751 * have _REG evaluated. _REG can only be evaluated after the
1752 * namespace initialization.
1753 * At this point, the GPE is not fully initialized, so do not to
1754 * handle the events.
1756 ret = acpi_config_boot_ec(ec, ec->handle, false, false);
1764 * If the DSDT EC is not functioning, we still need to prepare a fully
1765 * functioning ECDT EC first in order to handle the events.
1766 * https://bugzilla.kernel.org/show_bug.cgi?id=115021
1768 static int __init acpi_ec_ecdt_start(void)
1774 /* In case acpi_ec_ecdt_start() is called after acpi_ec_add() */
1775 if (!boot_ec_is_ecdt)
1779 * At this point, the namespace and the GPE is initialized, so
1780 * start to find the namespace objects and handle the events.
1782 * Note: ec->handle can be valid if this function is called after
1783 * acpi_ec_add(), hence the fast path.
1785 if (boot_ec->handle == ACPI_ROOT_OBJECT) {
1786 if (!acpi_ec_ecdt_get_handle(&handle))
1788 boot_ec->handle = handle;
1791 /* Register to ACPI bus with PM ops attached */
1792 return acpi_bus_register_early_device(ACPI_BUS_TYPE_ECDT_EC);
1797 * Some EC firmware variations refuses to respond QR_EC when SCI_EVT is not
1798 * set, for which case, we complete the QR_EC without issuing it to the
1800 * https://bugzilla.kernel.org/show_bug.cgi?id=82611
1801 * https://bugzilla.kernel.org/show_bug.cgi?id=97381
1803 static int ec_flag_query_handshake(const struct dmi_system_id *id)
1805 pr_debug("Detected the EC firmware requiring QR_EC issued when SCI_EVT set\n");
1806 EC_FLAGS_QUERY_HANDSHAKE = 1;
1812 * Some ECDTs contain wrong register addresses.
1814 * https://bugzilla.kernel.org/show_bug.cgi?id=12461
1816 static int ec_correct_ecdt(const struct dmi_system_id *id)
1818 pr_debug("Detected system needing ECDT address correction.\n");
1819 EC_FLAGS_CORRECT_ECDT = 1;
1824 * Some DSDTs contain wrong GPE setting.
1825 * Asus FX502VD/VE, GL702VMK, X550VXK, X580VD
1826 * https://bugzilla.kernel.org/show_bug.cgi?id=195651
1828 static int ec_honor_ecdt_gpe(const struct dmi_system_id *id)
1830 pr_debug("Detected system needing ignore DSDT GPE setting.\n");
1831 EC_FLAGS_IGNORE_DSDT_GPE = 1;
1835 static const struct dmi_system_id ec_dmi_table[] __initconst = {
1837 ec_correct_ecdt, "MSI MS-171F", {
1838 DMI_MATCH(DMI_SYS_VENDOR, "Micro-Star"),
1839 DMI_MATCH(DMI_PRODUCT_NAME, "MS-171F"),}, NULL},
1841 ec_honor_ecdt_gpe, "ASUS FX502VD", {
1842 DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK COMPUTER INC."),
1843 DMI_MATCH(DMI_PRODUCT_NAME, "FX502VD"),}, NULL},
1845 ec_honor_ecdt_gpe, "ASUS FX502VE", {
1846 DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK COMPUTER INC."),
1847 DMI_MATCH(DMI_PRODUCT_NAME, "FX502VE"),}, NULL},
1849 ec_honor_ecdt_gpe, "ASUS GL702VMK", {
1850 DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK COMPUTER INC."),
1851 DMI_MATCH(DMI_PRODUCT_NAME, "GL702VMK"),}, NULL},
1853 ec_honor_ecdt_gpe, "ASUS X550VXK", {
1854 DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK COMPUTER INC."),
1855 DMI_MATCH(DMI_PRODUCT_NAME, "X550VXK"),}, NULL},
1857 ec_honor_ecdt_gpe, "ASUS X580VD", {
1858 DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK COMPUTER INC."),
1859 DMI_MATCH(DMI_PRODUCT_NAME, "X580VD"),}, NULL},
1863 int __init acpi_ec_ecdt_probe(void)
1867 struct acpi_table_ecdt *ecdt_ptr;
1870 ec = acpi_ec_alloc();
1874 * Generate a boot ec context
1876 dmi_check_system(ec_dmi_table);
1877 status = acpi_get_table(ACPI_SIG_ECDT, 1,
1878 (struct acpi_table_header **)&ecdt_ptr);
1879 if (ACPI_FAILURE(status)) {
1884 if (!ecdt_ptr->control.address || !ecdt_ptr->data.address) {
1887 * https://bugzilla.kernel.org/show_bug.cgi?id=11880
1893 if (EC_FLAGS_CORRECT_ECDT) {
1894 ec->command_addr = ecdt_ptr->data.address;
1895 ec->data_addr = ecdt_ptr->control.address;
1897 ec->command_addr = ecdt_ptr->control.address;
1898 ec->data_addr = ecdt_ptr->data.address;
1900 ec->gpe = ecdt_ptr->gpe;
1903 * At this point, the namespace is not initialized, so do not find
1904 * the namespace objects, or handle the events.
1906 ret = acpi_config_boot_ec(ec, ACPI_ROOT_OBJECT, false, true);
1913 #ifdef CONFIG_PM_SLEEP
1914 static int acpi_ec_suspend(struct device *dev)
1916 struct acpi_ec *ec =
1917 acpi_driver_data(to_acpi_device(dev));
1919 if (acpi_sleep_no_ec_events() && ec_freeze_events)
1920 acpi_ec_disable_event(ec);
1924 static int acpi_ec_suspend_noirq(struct device *dev)
1926 struct acpi_ec *ec = acpi_driver_data(to_acpi_device(dev));
1929 * The SCI handler doesn't run at this point, so the GPE can be
1930 * masked at the low level without side effects.
1932 if (ec_no_wakeup && test_bit(EC_FLAGS_STARTED, &ec->flags) &&
1933 ec->reference_count >= 1)
1934 acpi_set_gpe(NULL, ec->gpe, ACPI_GPE_DISABLE);
1936 if (acpi_sleep_no_ec_events())
1937 acpi_ec_enter_noirq(ec);
1942 static int acpi_ec_resume_noirq(struct device *dev)
1944 struct acpi_ec *ec = acpi_driver_data(to_acpi_device(dev));
1946 if (acpi_sleep_no_ec_events())
1947 acpi_ec_leave_noirq(ec);
1949 if (ec_no_wakeup && test_bit(EC_FLAGS_STARTED, &ec->flags) &&
1950 ec->reference_count >= 1)
1951 acpi_set_gpe(NULL, ec->gpe, ACPI_GPE_ENABLE);
1956 static int acpi_ec_resume(struct device *dev)
1958 struct acpi_ec *ec =
1959 acpi_driver_data(to_acpi_device(dev));
1961 acpi_ec_enable_event(ec);
1966 static const struct dev_pm_ops acpi_ec_pm = {
1967 SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(acpi_ec_suspend_noirq, acpi_ec_resume_noirq)
1968 SET_SYSTEM_SLEEP_PM_OPS(acpi_ec_suspend, acpi_ec_resume)
1971 static int param_set_event_clearing(const char *val,
1972 const struct kernel_param *kp)
1976 if (!strncmp(val, "status", sizeof("status") - 1)) {
1977 ec_event_clearing = ACPI_EC_EVT_TIMING_STATUS;
1978 pr_info("Assuming SCI_EVT clearing on EC_SC accesses\n");
1979 } else if (!strncmp(val, "query", sizeof("query") - 1)) {
1980 ec_event_clearing = ACPI_EC_EVT_TIMING_QUERY;
1981 pr_info("Assuming SCI_EVT clearing on QR_EC writes\n");
1982 } else if (!strncmp(val, "event", sizeof("event") - 1)) {
1983 ec_event_clearing = ACPI_EC_EVT_TIMING_EVENT;
1984 pr_info("Assuming SCI_EVT clearing on event reads\n");
1990 static int param_get_event_clearing(char *buffer,
1991 const struct kernel_param *kp)
1993 switch (ec_event_clearing) {
1994 case ACPI_EC_EVT_TIMING_STATUS:
1995 return sprintf(buffer, "status");
1996 case ACPI_EC_EVT_TIMING_QUERY:
1997 return sprintf(buffer, "query");
1998 case ACPI_EC_EVT_TIMING_EVENT:
1999 return sprintf(buffer, "event");
2001 return sprintf(buffer, "invalid");
2006 module_param_call(ec_event_clearing, param_set_event_clearing, param_get_event_clearing,
2008 MODULE_PARM_DESC(ec_event_clearing, "Assumed SCI_EVT clearing timing");
2010 static struct acpi_driver acpi_ec_driver = {
2012 .class = ACPI_EC_CLASS,
2013 .ids = ec_device_ids,
2016 .remove = acpi_ec_remove,
2018 .drv.pm = &acpi_ec_pm,
2021 static inline int acpi_ec_query_init(void)
2024 ec_query_wq = alloc_workqueue("kec_query", 0,
2032 static inline void acpi_ec_query_exit(void)
2035 destroy_workqueue(ec_query_wq);
2040 static const struct dmi_system_id acpi_ec_no_wakeup[] = {
2042 .ident = "Thinkpad X1 Carbon 6th",
2044 DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
2045 DMI_MATCH(DMI_PRODUCT_FAMILY, "Thinkpad X1 Carbon 6th"),
2049 .ident = "ThinkPad X1 Carbon 6th",
2051 DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
2052 DMI_MATCH(DMI_PRODUCT_FAMILY, "ThinkPad X1 Carbon 6th"),
2056 .ident = "ThinkPad X1 Yoga 3rd",
2058 DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
2059 DMI_MATCH(DMI_PRODUCT_FAMILY, "ThinkPad X1 Yoga 3rd"),
2065 int __init acpi_ec_init(void)
2068 int ecdt_fail, dsdt_fail;
2070 /* register workqueue for _Qxx evaluations */
2071 result = acpi_ec_query_init();
2076 * Disable EC wakeup on following systems to prevent periodic
2077 * wakeup from EC GPE.
2079 if (dmi_check_system(acpi_ec_no_wakeup)) {
2080 ec_no_wakeup = true;
2081 pr_debug("Disabling EC wakeup on suspend-to-idle\n");
2084 /* Drivers must be started after acpi_ec_query_init() */
2085 dsdt_fail = acpi_bus_register_driver(&acpi_ec_driver);
2087 * Register ECDT to ACPI bus only when PNP0C09 probe fails. This is
2088 * useful for platforms (confirmed on ASUS X550ZE) with valid ECDT
2089 * settings but invalid DSDT settings.
2090 * https://bugzilla.kernel.org/show_bug.cgi?id=196847
2092 ecdt_fail = acpi_ec_ecdt_start();
2093 return ecdt_fail && dsdt_fail ? -ENODEV : 0;
2096 /* EC driver currently not unloadable */
2098 static void __exit acpi_ec_exit(void)
2101 acpi_bus_unregister_driver(&acpi_ec_driver);
2102 acpi_ec_query_exit();