1 // SPDX-License-Identifier: GPL-2.0-or-later
3 * ec.c - ACPI Embedded Controller Driver (v3)
5 * Copyright (C) 2001-2015 Intel Corporation
6 * Author: 2014, 2015 Lv Zheng <lv.zheng@intel.com>
7 * 2006, 2007 Alexey Starikovskiy <alexey.y.starikovskiy@intel.com>
8 * 2006 Denis Sadykov <denis.m.sadykov@intel.com>
9 * 2004 Luming Yu <luming.yu@intel.com>
10 * 2001, 2002 Andy Grover <andrew.grover@intel.com>
11 * 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
12 * Copyright (C) 2008 Alexey Starikovskiy <astarikovskiy@suse.de>
15 /* Uncomment next line to get verbose printout */
17 #define pr_fmt(fmt) "ACPI: EC: " fmt
19 #include <linux/kernel.h>
20 #include <linux/module.h>
21 #include <linux/init.h>
22 #include <linux/types.h>
23 #include <linux/delay.h>
24 #include <linux/interrupt.h>
25 #include <linux/list.h>
26 #include <linux/spinlock.h>
27 #include <linux/slab.h>
28 #include <linux/suspend.h>
29 #include <linux/acpi.h>
30 #include <linux/dmi.h>
35 #define ACPI_EC_CLASS "embedded_controller"
36 #define ACPI_EC_DEVICE_NAME "Embedded Controller"
37 #define ACPI_EC_FILE_INFO "info"
39 /* EC status register */
40 #define ACPI_EC_FLAG_OBF 0x01 /* Output buffer full */
41 #define ACPI_EC_FLAG_IBF 0x02 /* Input buffer full */
42 #define ACPI_EC_FLAG_CMD 0x08 /* Input buffer contains a command */
43 #define ACPI_EC_FLAG_BURST 0x10 /* burst mode */
44 #define ACPI_EC_FLAG_SCI 0x20 /* EC-SCI occurred */
47 * The SCI_EVT clearing timing is not defined by the ACPI specification.
48 * This leads to lots of practical timing issues for the host EC driver.
49 * The following variations are defined (from the target EC firmware's
51 * STATUS: After indicating SCI_EVT edge triggered IRQ to the host, the
52 * target can clear SCI_EVT at any time so long as the host can see
53 * the indication by reading the status register (EC_SC). So the
54 * host should re-check SCI_EVT after the first time the SCI_EVT
55 * indication is seen, which is the same time the query request
56 * (QR_EC) is written to the command register (EC_CMD). SCI_EVT set
57 * at any later time could indicate another event. Normally such
58 * kind of EC firmware has implemented an event queue and will
59 * return 0x00 to indicate "no outstanding event".
60 * QUERY: After seeing the query request (QR_EC) written to the command
61 * register (EC_CMD) by the host and having prepared the responding
62 * event value in the data register (EC_DATA), the target can safely
63 * clear SCI_EVT because the target can confirm that the current
64 * event is being handled by the host. The host then should check
65 * SCI_EVT right after reading the event response from the data
67 * EVENT: After seeing the event response read from the data register
68 * (EC_DATA) by the host, the target can clear SCI_EVT. As the
69 * target requires time to notice the change in the data register
70 * (EC_DATA), the host may be required to wait additional guarding
71 * time before checking the SCI_EVT again. Such guarding may not be
72 * necessary if the host is notified via another IRQ.
74 #define ACPI_EC_EVT_TIMING_STATUS 0x00
75 #define ACPI_EC_EVT_TIMING_QUERY 0x01
76 #define ACPI_EC_EVT_TIMING_EVENT 0x02
80 ACPI_EC_COMMAND_READ
= 0x80,
81 ACPI_EC_COMMAND_WRITE
= 0x81,
82 ACPI_EC_BURST_ENABLE
= 0x82,
83 ACPI_EC_BURST_DISABLE
= 0x83,
84 ACPI_EC_COMMAND_QUERY
= 0x84,
87 #define ACPI_EC_DELAY 500 /* Wait 500ms max. during EC ops */
88 #define ACPI_EC_UDELAY_GLK 1000 /* Wait 1ms max. to get global lock */
89 #define ACPI_EC_UDELAY_POLL 550 /* Wait 1ms for EC transaction polling */
90 #define ACPI_EC_CLEAR_MAX 100 /* Maximum number of events to query
91 * when trying to clear the EC */
92 #define ACPI_EC_MAX_QUERIES 16 /* Maximum number of parallel queries */
95 EC_FLAGS_QUERY_ENABLED
, /* Query is enabled */
96 EC_FLAGS_QUERY_PENDING
, /* Query is pending */
97 EC_FLAGS_QUERY_GUARDING
, /* Guard for SCI_EVT check */
98 EC_FLAGS_EVENT_HANDLER_INSTALLED
, /* Event handler installed */
99 EC_FLAGS_EC_HANDLER_INSTALLED
, /* OpReg handler installed */
100 EC_FLAGS_QUERY_METHODS_INSTALLED
, /* _Qxx handlers installed */
101 EC_FLAGS_STARTED
, /* Driver is started */
102 EC_FLAGS_STOPPED
, /* Driver is stopped */
103 EC_FLAGS_EVENTS_MASKED
, /* Events masked */
106 #define ACPI_EC_COMMAND_POLL 0x01 /* Available for command byte */
107 #define ACPI_EC_COMMAND_COMPLETE 0x02 /* Completed last byte */
109 /* ec.c is compiled in acpi namespace so this shows up as acpi.ec_delay param */
110 static unsigned int ec_delay __read_mostly
= ACPI_EC_DELAY
;
111 module_param(ec_delay
, uint
, 0644);
112 MODULE_PARM_DESC(ec_delay
, "Timeout(ms) waited until an EC command completes");
114 static unsigned int ec_max_queries __read_mostly
= ACPI_EC_MAX_QUERIES
;
115 module_param(ec_max_queries
, uint
, 0644);
116 MODULE_PARM_DESC(ec_max_queries
, "Maximum parallel _Qxx evaluations");
118 static bool ec_busy_polling __read_mostly
;
119 module_param(ec_busy_polling
, bool, 0644);
120 MODULE_PARM_DESC(ec_busy_polling
, "Use busy polling to advance EC transaction");
122 static unsigned int ec_polling_guard __read_mostly
= ACPI_EC_UDELAY_POLL
;
123 module_param(ec_polling_guard
, uint
, 0644);
124 MODULE_PARM_DESC(ec_polling_guard
, "Guard time(us) between EC accesses in polling modes");
126 static unsigned int ec_event_clearing __read_mostly
= ACPI_EC_EVT_TIMING_QUERY
;
129 * If the number of false interrupts per one transaction exceeds
130 * this threshold, will think there is a GPE storm happened and
131 * will disable the GPE for normal transaction.
133 static unsigned int ec_storm_threshold __read_mostly
= 8;
134 module_param(ec_storm_threshold
, uint
, 0644);
135 MODULE_PARM_DESC(ec_storm_threshold
, "Maxim false GPE numbers not considered as GPE storm");
137 static bool ec_freeze_events __read_mostly
= false;
138 module_param(ec_freeze_events
, bool, 0644);
139 MODULE_PARM_DESC(ec_freeze_events
, "Disabling event handling during suspend/resume");
141 static bool ec_no_wakeup __read_mostly
;
142 module_param(ec_no_wakeup
, bool, 0644);
143 MODULE_PARM_DESC(ec_no_wakeup
, "Do not wake up from suspend-to-idle");
145 struct acpi_ec_query_handler
{
146 struct list_head node
;
147 acpi_ec_query_func func
;
157 unsigned short irq_count
;
166 struct acpi_ec_query
{
167 struct transaction transaction
;
168 struct work_struct work
;
169 struct acpi_ec_query_handler
*handler
;
172 static int acpi_ec_query(struct acpi_ec
*ec
, u8
*data
);
173 static void advance_transaction(struct acpi_ec
*ec
);
174 static void acpi_ec_event_handler(struct work_struct
*work
);
175 static void acpi_ec_event_processor(struct work_struct
*work
);
177 struct acpi_ec
*first_ec
;
178 EXPORT_SYMBOL(first_ec
);
180 static struct acpi_ec
*boot_ec
;
181 static bool boot_ec_is_ecdt
= false;
182 static struct workqueue_struct
*ec_wq
;
183 static struct workqueue_struct
*ec_query_wq
;
185 static int EC_FLAGS_QUERY_HANDSHAKE
; /* Needs QR_EC issued when SCI_EVT set */
186 static int EC_FLAGS_CORRECT_ECDT
; /* Needs ECDT port address correction */
187 static int EC_FLAGS_IGNORE_DSDT_GPE
; /* Needs ECDT GPE as correction setting */
188 static int EC_FLAGS_CLEAR_ON_RESUME
; /* Needs acpi_ec_clear() on boot/resume */
190 /* --------------------------------------------------------------------------
192 * -------------------------------------------------------------------------- */
195 * Splitters used by the developers to track the boundary of the EC
196 * handling processes.
199 #define EC_DBG_SEP " "
200 #define EC_DBG_DRV "+++++"
201 #define EC_DBG_STM "====="
202 #define EC_DBG_REQ "*****"
203 #define EC_DBG_EVT "#####"
205 #define EC_DBG_SEP ""
212 #define ec_log_raw(fmt, ...) \
213 pr_info(fmt "\n", ##__VA_ARGS__)
214 #define ec_dbg_raw(fmt, ...) \
215 pr_debug(fmt "\n", ##__VA_ARGS__)
216 #define ec_log(filter, fmt, ...) \
217 ec_log_raw(filter EC_DBG_SEP fmt EC_DBG_SEP filter, ##__VA_ARGS__)
218 #define ec_dbg(filter, fmt, ...) \
219 ec_dbg_raw(filter EC_DBG_SEP fmt EC_DBG_SEP filter, ##__VA_ARGS__)
221 #define ec_log_drv(fmt, ...) \
222 ec_log(EC_DBG_DRV, fmt, ##__VA_ARGS__)
223 #define ec_dbg_drv(fmt, ...) \
224 ec_dbg(EC_DBG_DRV, fmt, ##__VA_ARGS__)
225 #define ec_dbg_stm(fmt, ...) \
226 ec_dbg(EC_DBG_STM, fmt, ##__VA_ARGS__)
227 #define ec_dbg_req(fmt, ...) \
228 ec_dbg(EC_DBG_REQ, fmt, ##__VA_ARGS__)
229 #define ec_dbg_evt(fmt, ...) \
230 ec_dbg(EC_DBG_EVT, fmt, ##__VA_ARGS__)
231 #define ec_dbg_ref(ec, fmt, ...) \
232 ec_dbg_raw("%lu: " fmt, ec->reference_count, ## __VA_ARGS__)
234 /* --------------------------------------------------------------------------
236 * -------------------------------------------------------------------------- */
238 static bool acpi_ec_started(struct acpi_ec
*ec
)
240 return test_bit(EC_FLAGS_STARTED
, &ec
->flags
) &&
241 !test_bit(EC_FLAGS_STOPPED
, &ec
->flags
);
244 static bool acpi_ec_event_enabled(struct acpi_ec
*ec
)
247 * There is an OSPM early stage logic. During the early stages
248 * (boot/resume), OSPMs shouldn't enable the event handling, only
249 * the EC transactions are allowed to be performed.
251 if (!test_bit(EC_FLAGS_QUERY_ENABLED
, &ec
->flags
))
254 * However, disabling the event handling is experimental for late
255 * stage (suspend), and is controlled by the boot parameter of
256 * "ec_freeze_events":
257 * 1. true: The EC event handling is disabled before entering
259 * 2. false: The EC event handling is automatically disabled as
260 * soon as the EC driver is stopped.
262 if (ec_freeze_events
)
263 return acpi_ec_started(ec
);
265 return test_bit(EC_FLAGS_STARTED
, &ec
->flags
);
268 static bool acpi_ec_flushed(struct acpi_ec
*ec
)
270 return ec
->reference_count
== 1;
273 /* --------------------------------------------------------------------------
275 * -------------------------------------------------------------------------- */
277 static inline u8
acpi_ec_read_status(struct acpi_ec
*ec
)
279 u8 x
= inb(ec
->command_addr
);
281 ec_dbg_raw("EC_SC(R) = 0x%2.2x "
282 "SCI_EVT=%d BURST=%d CMD=%d IBF=%d OBF=%d",
284 !!(x
& ACPI_EC_FLAG_SCI
),
285 !!(x
& ACPI_EC_FLAG_BURST
),
286 !!(x
& ACPI_EC_FLAG_CMD
),
287 !!(x
& ACPI_EC_FLAG_IBF
),
288 !!(x
& ACPI_EC_FLAG_OBF
));
292 static inline u8
acpi_ec_read_data(struct acpi_ec
*ec
)
294 u8 x
= inb(ec
->data_addr
);
296 ec
->timestamp
= jiffies
;
297 ec_dbg_raw("EC_DATA(R) = 0x%2.2x", x
);
301 static inline void acpi_ec_write_cmd(struct acpi_ec
*ec
, u8 command
)
303 ec_dbg_raw("EC_SC(W) = 0x%2.2x", command
);
304 outb(command
, ec
->command_addr
);
305 ec
->timestamp
= jiffies
;
308 static inline void acpi_ec_write_data(struct acpi_ec
*ec
, u8 data
)
310 ec_dbg_raw("EC_DATA(W) = 0x%2.2x", data
);
311 outb(data
, ec
->data_addr
);
312 ec
->timestamp
= jiffies
;
315 #if defined(DEBUG) || defined(CONFIG_DYNAMIC_DEBUG)
316 static const char *acpi_ec_cmd_string(u8 cmd
)
333 #define acpi_ec_cmd_string(cmd) "UNDEF"
336 /* --------------------------------------------------------------------------
338 * -------------------------------------------------------------------------- */
340 static inline bool acpi_ec_is_gpe_raised(struct acpi_ec
*ec
)
342 acpi_event_status gpe_status
= 0;
344 (void)acpi_get_gpe_status(NULL
, ec
->gpe
, &gpe_status
);
345 return (gpe_status
& ACPI_EVENT_FLAG_STATUS_SET
) ? true : false;
348 static inline void acpi_ec_enable_gpe(struct acpi_ec
*ec
, bool open
)
351 acpi_enable_gpe(NULL
, ec
->gpe
);
353 BUG_ON(ec
->reference_count
< 1);
354 acpi_set_gpe(NULL
, ec
->gpe
, ACPI_GPE_ENABLE
);
356 if (acpi_ec_is_gpe_raised(ec
)) {
358 * On some platforms, EN=1 writes cannot trigger GPE. So
359 * software need to manually trigger a pseudo GPE event on
362 ec_dbg_raw("Polling quirk");
363 advance_transaction(ec
);
367 static inline void acpi_ec_disable_gpe(struct acpi_ec
*ec
, bool close
)
370 acpi_disable_gpe(NULL
, ec
->gpe
);
372 BUG_ON(ec
->reference_count
< 1);
373 acpi_set_gpe(NULL
, ec
->gpe
, ACPI_GPE_DISABLE
);
377 static inline void acpi_ec_clear_gpe(struct acpi_ec
*ec
)
380 * GPE STS is a W1C register, which means:
381 * 1. Software can clear it without worrying about clearing other
382 * GPEs' STS bits when the hardware sets them in parallel.
383 * 2. As long as software can ensure only clearing it when it is
384 * set, hardware won't set it in parallel.
385 * So software can clear GPE in any contexts.
386 * Warning: do not move the check into advance_transaction() as the
387 * EC commands will be sent without GPE raised.
389 if (!acpi_ec_is_gpe_raised(ec
))
391 acpi_clear_gpe(NULL
, ec
->gpe
);
394 /* --------------------------------------------------------------------------
395 * Transaction Management
396 * -------------------------------------------------------------------------- */
398 static void acpi_ec_submit_request(struct acpi_ec
*ec
)
400 ec
->reference_count
++;
401 if (test_bit(EC_FLAGS_EVENT_HANDLER_INSTALLED
, &ec
->flags
) &&
402 ec
->gpe
>= 0 && ec
->reference_count
== 1)
403 acpi_ec_enable_gpe(ec
, true);
406 static void acpi_ec_complete_request(struct acpi_ec
*ec
)
408 bool flushed
= false;
410 ec
->reference_count
--;
411 if (test_bit(EC_FLAGS_EVENT_HANDLER_INSTALLED
, &ec
->flags
) &&
412 ec
->gpe
>= 0 && ec
->reference_count
== 0)
413 acpi_ec_disable_gpe(ec
, true);
414 flushed
= acpi_ec_flushed(ec
);
419 static void acpi_ec_mask_events(struct acpi_ec
*ec
)
421 if (!test_bit(EC_FLAGS_EVENTS_MASKED
, &ec
->flags
)) {
423 acpi_ec_disable_gpe(ec
, false);
425 disable_irq_nosync(ec
->irq
);
427 ec_dbg_drv("Polling enabled");
428 set_bit(EC_FLAGS_EVENTS_MASKED
, &ec
->flags
);
432 static void acpi_ec_unmask_events(struct acpi_ec
*ec
)
434 if (test_bit(EC_FLAGS_EVENTS_MASKED
, &ec
->flags
)) {
435 clear_bit(EC_FLAGS_EVENTS_MASKED
, &ec
->flags
);
437 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_events(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 queue_work(ec_wq
, &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_events(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");
503 * Process _Q events that might have accumulated in the EC.
504 * Run with locked ec mutex.
506 static void acpi_ec_clear(struct acpi_ec
*ec
)
511 for (i
= 0; i
< ACPI_EC_CLEAR_MAX
; i
++) {
512 status
= acpi_ec_query(ec
, &value
);
513 if (status
|| !value
)
516 if (unlikely(i
== ACPI_EC_CLEAR_MAX
))
517 pr_warn("Warning: Maximum of %d stale EC events cleared\n", i
);
519 pr_info("%d stale EC events cleared\n", i
);
522 static void acpi_ec_enable_event(struct acpi_ec
*ec
)
526 spin_lock_irqsave(&ec
->lock
, flags
);
527 if (acpi_ec_started(ec
))
528 __acpi_ec_enable_event(ec
);
529 spin_unlock_irqrestore(&ec
->lock
, flags
);
531 /* Drain additional events if hardware requires that */
532 if (EC_FLAGS_CLEAR_ON_RESUME
)
536 #ifdef CONFIG_PM_SLEEP
537 static void __acpi_ec_flush_work(void)
539 drain_workqueue(ec_wq
); /* flush ec->work */
540 flush_workqueue(ec_query_wq
); /* flush queries */
543 static void acpi_ec_disable_event(struct acpi_ec
*ec
)
547 spin_lock_irqsave(&ec
->lock
, flags
);
548 __acpi_ec_disable_event(ec
);
549 spin_unlock_irqrestore(&ec
->lock
, flags
);
552 * When ec_freeze_events is true, we need to flush events in
553 * the proper position before entering the noirq stage.
555 __acpi_ec_flush_work();
558 void acpi_ec_flush_work(void)
560 /* Without ec_wq there is nothing to flush. */
564 __acpi_ec_flush_work();
566 #endif /* CONFIG_PM_SLEEP */
568 static bool acpi_ec_guard_event(struct acpi_ec
*ec
)
573 spin_lock_irqsave(&ec
->lock
, flags
);
575 * If firmware SCI_EVT clearing timing is "event", we actually
576 * don't know when the SCI_EVT will be cleared by firmware after
577 * evaluating _Qxx, so we need to re-check SCI_EVT after waiting an
580 * The guarding period begins when EC_FLAGS_QUERY_PENDING is
581 * flagged, which means SCI_EVT check has just been performed.
582 * But if the current transaction is ACPI_EC_COMMAND_QUERY, the
583 * guarding should have already been performed (via
584 * EC_FLAGS_QUERY_GUARDING) and should not be applied so that the
585 * ACPI_EC_COMMAND_QUERY transaction can be transitioned into
586 * ACPI_EC_COMMAND_POLL state immediately.
588 if (ec_event_clearing
== ACPI_EC_EVT_TIMING_STATUS
||
589 ec_event_clearing
== ACPI_EC_EVT_TIMING_QUERY
||
590 !test_bit(EC_FLAGS_QUERY_PENDING
, &ec
->flags
) ||
591 (ec
->curr
&& ec
->curr
->command
== ACPI_EC_COMMAND_QUERY
))
593 spin_unlock_irqrestore(&ec
->lock
, flags
);
597 static int ec_transaction_polled(struct acpi_ec
*ec
)
602 spin_lock_irqsave(&ec
->lock
, flags
);
603 if (ec
->curr
&& (ec
->curr
->flags
& ACPI_EC_COMMAND_POLL
))
605 spin_unlock_irqrestore(&ec
->lock
, flags
);
609 static int ec_transaction_completed(struct acpi_ec
*ec
)
614 spin_lock_irqsave(&ec
->lock
, flags
);
615 if (ec
->curr
&& (ec
->curr
->flags
& ACPI_EC_COMMAND_COMPLETE
))
617 spin_unlock_irqrestore(&ec
->lock
, flags
);
621 static inline void ec_transaction_transition(struct acpi_ec
*ec
, unsigned long flag
)
623 ec
->curr
->flags
|= flag
;
624 if (ec
->curr
->command
== ACPI_EC_COMMAND_QUERY
) {
625 if (ec_event_clearing
== ACPI_EC_EVT_TIMING_STATUS
&&
626 flag
== ACPI_EC_COMMAND_POLL
)
627 acpi_ec_complete_query(ec
);
628 if (ec_event_clearing
== ACPI_EC_EVT_TIMING_QUERY
&&
629 flag
== ACPI_EC_COMMAND_COMPLETE
)
630 acpi_ec_complete_query(ec
);
631 if (ec_event_clearing
== ACPI_EC_EVT_TIMING_EVENT
&&
632 flag
== ACPI_EC_COMMAND_COMPLETE
)
633 set_bit(EC_FLAGS_QUERY_GUARDING
, &ec
->flags
);
637 static void advance_transaction(struct acpi_ec
*ec
)
639 struct transaction
*t
;
643 ec_dbg_stm("%s (%d)", in_interrupt() ? "IRQ" : "TASK",
646 * By always clearing STS before handling all indications, we can
647 * ensure a hardware STS 0->1 change after this clearing can always
648 * trigger a GPE interrupt.
651 acpi_ec_clear_gpe(ec
);
653 status
= acpi_ec_read_status(ec
);
656 * Another IRQ or a guarded polling mode advancement is detected,
657 * the next QR_EC submission is then allowed.
659 if (!t
|| !(t
->flags
& ACPI_EC_COMMAND_POLL
)) {
660 if (ec_event_clearing
== ACPI_EC_EVT_TIMING_EVENT
&&
661 (!ec
->nr_pending_queries
||
662 test_bit(EC_FLAGS_QUERY_GUARDING
, &ec
->flags
))) {
663 clear_bit(EC_FLAGS_QUERY_GUARDING
, &ec
->flags
);
664 acpi_ec_complete_query(ec
);
669 if (t
->flags
& ACPI_EC_COMMAND_POLL
) {
670 if (t
->wlen
> t
->wi
) {
671 if ((status
& ACPI_EC_FLAG_IBF
) == 0)
672 acpi_ec_write_data(ec
, t
->wdata
[t
->wi
++]);
675 } else if (t
->rlen
> t
->ri
) {
676 if ((status
& ACPI_EC_FLAG_OBF
) == 1) {
677 t
->rdata
[t
->ri
++] = acpi_ec_read_data(ec
);
678 if (t
->rlen
== t
->ri
) {
679 ec_transaction_transition(ec
, ACPI_EC_COMMAND_COMPLETE
);
680 if (t
->command
== ACPI_EC_COMMAND_QUERY
)
681 ec_dbg_evt("Command(%s) completed by hardware",
682 acpi_ec_cmd_string(ACPI_EC_COMMAND_QUERY
));
687 } else if (t
->wlen
== t
->wi
&&
688 (status
& ACPI_EC_FLAG_IBF
) == 0) {
689 ec_transaction_transition(ec
, ACPI_EC_COMMAND_COMPLETE
);
694 if (EC_FLAGS_QUERY_HANDSHAKE
&&
695 !(status
& ACPI_EC_FLAG_SCI
) &&
696 (t
->command
== ACPI_EC_COMMAND_QUERY
)) {
697 ec_transaction_transition(ec
, ACPI_EC_COMMAND_POLL
);
698 t
->rdata
[t
->ri
++] = 0x00;
699 ec_transaction_transition(ec
, ACPI_EC_COMMAND_COMPLETE
);
700 ec_dbg_evt("Command(%s) completed by software",
701 acpi_ec_cmd_string(ACPI_EC_COMMAND_QUERY
));
703 } else if ((status
& ACPI_EC_FLAG_IBF
) == 0) {
704 acpi_ec_write_cmd(ec
, t
->command
);
705 ec_transaction_transition(ec
, ACPI_EC_COMMAND_POLL
);
712 * If SCI bit is set, then don't think it's a false IRQ
713 * otherwise will take a not handled IRQ as a false one.
715 if (!(status
& ACPI_EC_FLAG_SCI
)) {
716 if (in_interrupt() && t
) {
717 if (t
->irq_count
< ec_storm_threshold
)
719 /* Allow triggering on 0 threshold */
720 if (t
->irq_count
== ec_storm_threshold
)
721 acpi_ec_mask_events(ec
);
725 if (status
& ACPI_EC_FLAG_SCI
)
726 acpi_ec_submit_query(ec
);
727 if (wakeup
&& in_interrupt())
731 static void start_transaction(struct acpi_ec
*ec
)
733 ec
->curr
->irq_count
= ec
->curr
->wi
= ec
->curr
->ri
= 0;
737 static int ec_guard(struct acpi_ec
*ec
)
739 unsigned long guard
= usecs_to_jiffies(ec
->polling_guard
);
740 unsigned long timeout
= ec
->timestamp
+ guard
;
742 /* Ensure guarding period before polling EC status */
744 if (ec
->busy_polling
) {
745 /* Perform busy polling */
746 if (ec_transaction_completed(ec
))
748 udelay(jiffies_to_usecs(guard
));
751 * Perform wait polling
752 * 1. Wait the transaction to be completed by the
753 * GPE handler after the transaction enters
754 * ACPI_EC_COMMAND_POLL state.
755 * 2. A special guarding logic is also required
756 * for event clearing mode "event" before the
757 * transaction enters ACPI_EC_COMMAND_POLL
760 if (!ec_transaction_polled(ec
) &&
761 !acpi_ec_guard_event(ec
))
763 if (wait_event_timeout(ec
->wait
,
764 ec_transaction_completed(ec
),
768 } while (time_before(jiffies
, timeout
));
772 static int ec_poll(struct acpi_ec
*ec
)
775 int repeat
= 5; /* number of command restarts */
778 unsigned long delay
= jiffies
+
779 msecs_to_jiffies(ec_delay
);
783 spin_lock_irqsave(&ec
->lock
, flags
);
784 advance_transaction(ec
);
785 spin_unlock_irqrestore(&ec
->lock
, flags
);
786 } while (time_before(jiffies
, delay
));
787 pr_debug("controller reset, restart transaction\n");
788 spin_lock_irqsave(&ec
->lock
, flags
);
789 start_transaction(ec
);
790 spin_unlock_irqrestore(&ec
->lock
, flags
);
795 static int acpi_ec_transaction_unlocked(struct acpi_ec
*ec
,
796 struct transaction
*t
)
801 /* start transaction */
802 spin_lock_irqsave(&ec
->lock
, tmp
);
803 /* Enable GPE for command processing (IBF=0/OBF=1) */
804 if (!acpi_ec_submit_flushable_request(ec
)) {
808 ec_dbg_ref(ec
, "Increase command");
809 /* following two actions should be kept atomic */
811 ec_dbg_req("Command(%s) started", acpi_ec_cmd_string(t
->command
));
812 start_transaction(ec
);
813 spin_unlock_irqrestore(&ec
->lock
, tmp
);
817 spin_lock_irqsave(&ec
->lock
, tmp
);
818 if (t
->irq_count
== ec_storm_threshold
)
819 acpi_ec_unmask_events(ec
);
820 ec_dbg_req("Command(%s) stopped", acpi_ec_cmd_string(t
->command
));
822 /* Disable GPE for command processing (IBF=0/OBF=1) */
823 acpi_ec_complete_request(ec
);
824 ec_dbg_ref(ec
, "Decrease command");
826 spin_unlock_irqrestore(&ec
->lock
, tmp
);
830 static int acpi_ec_transaction(struct acpi_ec
*ec
, struct transaction
*t
)
835 if (!ec
|| (!t
) || (t
->wlen
&& !t
->wdata
) || (t
->rlen
&& !t
->rdata
))
838 memset(t
->rdata
, 0, t
->rlen
);
840 mutex_lock(&ec
->mutex
);
841 if (ec
->global_lock
) {
842 status
= acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK
, &glk
);
843 if (ACPI_FAILURE(status
)) {
849 status
= acpi_ec_transaction_unlocked(ec
, t
);
852 acpi_release_global_lock(glk
);
854 mutex_unlock(&ec
->mutex
);
858 static int acpi_ec_burst_enable(struct acpi_ec
*ec
)
861 struct transaction t
= {.command
= ACPI_EC_BURST_ENABLE
,
862 .wdata
= NULL
, .rdata
= &d
,
863 .wlen
= 0, .rlen
= 1};
865 return acpi_ec_transaction(ec
, &t
);
868 static int acpi_ec_burst_disable(struct acpi_ec
*ec
)
870 struct transaction t
= {.command
= ACPI_EC_BURST_DISABLE
,
871 .wdata
= NULL
, .rdata
= NULL
,
872 .wlen
= 0, .rlen
= 0};
874 return (acpi_ec_read_status(ec
) & ACPI_EC_FLAG_BURST
) ?
875 acpi_ec_transaction(ec
, &t
) : 0;
878 static int acpi_ec_read(struct acpi_ec
*ec
, u8 address
, u8
*data
)
882 struct transaction t
= {.command
= ACPI_EC_COMMAND_READ
,
883 .wdata
= &address
, .rdata
= &d
,
884 .wlen
= 1, .rlen
= 1};
886 result
= acpi_ec_transaction(ec
, &t
);
891 static int acpi_ec_write(struct acpi_ec
*ec
, u8 address
, u8 data
)
893 u8 wdata
[2] = { address
, data
};
894 struct transaction t
= {.command
= ACPI_EC_COMMAND_WRITE
,
895 .wdata
= wdata
, .rdata
= NULL
,
896 .wlen
= 2, .rlen
= 0};
898 return acpi_ec_transaction(ec
, &t
);
901 int ec_read(u8 addr
, u8
*val
)
909 err
= acpi_ec_read(first_ec
, addr
, &temp_data
);
917 EXPORT_SYMBOL(ec_read
);
919 int ec_write(u8 addr
, u8 val
)
926 err
= acpi_ec_write(first_ec
, addr
, val
);
930 EXPORT_SYMBOL(ec_write
);
932 int ec_transaction(u8 command
,
933 const u8
*wdata
, unsigned wdata_len
,
934 u8
*rdata
, unsigned rdata_len
)
936 struct transaction t
= {.command
= command
,
937 .wdata
= wdata
, .rdata
= rdata
,
938 .wlen
= wdata_len
, .rlen
= rdata_len
};
943 return acpi_ec_transaction(first_ec
, &t
);
945 EXPORT_SYMBOL(ec_transaction
);
947 /* Get the handle to the EC device */
948 acpi_handle
ec_get_handle(void)
952 return first_ec
->handle
;
954 EXPORT_SYMBOL(ec_get_handle
);
956 static void acpi_ec_start(struct acpi_ec
*ec
, bool resuming
)
960 spin_lock_irqsave(&ec
->lock
, flags
);
961 if (!test_and_set_bit(EC_FLAGS_STARTED
, &ec
->flags
)) {
962 ec_dbg_drv("Starting EC");
963 /* Enable GPE for event processing (SCI_EVT=1) */
965 acpi_ec_submit_request(ec
);
966 ec_dbg_ref(ec
, "Increase driver");
968 ec_log_drv("EC started");
970 spin_unlock_irqrestore(&ec
->lock
, flags
);
973 static bool acpi_ec_stopped(struct acpi_ec
*ec
)
978 spin_lock_irqsave(&ec
->lock
, flags
);
979 flushed
= acpi_ec_flushed(ec
);
980 spin_unlock_irqrestore(&ec
->lock
, flags
);
984 static void acpi_ec_stop(struct acpi_ec
*ec
, bool suspending
)
988 spin_lock_irqsave(&ec
->lock
, flags
);
989 if (acpi_ec_started(ec
)) {
990 ec_dbg_drv("Stopping EC");
991 set_bit(EC_FLAGS_STOPPED
, &ec
->flags
);
992 spin_unlock_irqrestore(&ec
->lock
, flags
);
993 wait_event(ec
->wait
, acpi_ec_stopped(ec
));
994 spin_lock_irqsave(&ec
->lock
, flags
);
995 /* Disable GPE for event processing (SCI_EVT=1) */
997 acpi_ec_complete_request(ec
);
998 ec_dbg_ref(ec
, "Decrease driver");
999 } else if (!ec_freeze_events
)
1000 __acpi_ec_disable_event(ec
);
1001 clear_bit(EC_FLAGS_STARTED
, &ec
->flags
);
1002 clear_bit(EC_FLAGS_STOPPED
, &ec
->flags
);
1003 ec_log_drv("EC stopped");
1005 spin_unlock_irqrestore(&ec
->lock
, flags
);
1008 static void acpi_ec_enter_noirq(struct acpi_ec
*ec
)
1010 unsigned long flags
;
1012 spin_lock_irqsave(&ec
->lock
, flags
);
1013 ec
->busy_polling
= true;
1014 ec
->polling_guard
= 0;
1015 ec_log_drv("interrupt blocked");
1016 spin_unlock_irqrestore(&ec
->lock
, flags
);
1019 static void acpi_ec_leave_noirq(struct acpi_ec
*ec
)
1021 unsigned long flags
;
1023 spin_lock_irqsave(&ec
->lock
, flags
);
1024 ec
->busy_polling
= ec_busy_polling
;
1025 ec
->polling_guard
= ec_polling_guard
;
1026 ec_log_drv("interrupt unblocked");
1027 spin_unlock_irqrestore(&ec
->lock
, flags
);
1030 void acpi_ec_block_transactions(void)
1032 struct acpi_ec
*ec
= first_ec
;
1037 mutex_lock(&ec
->mutex
);
1038 /* Prevent transactions from being carried out */
1039 acpi_ec_stop(ec
, true);
1040 mutex_unlock(&ec
->mutex
);
1043 void acpi_ec_unblock_transactions(void)
1046 * Allow transactions to happen again (this function is called from
1047 * atomic context during wakeup, so we don't need to acquire the mutex).
1050 acpi_ec_start(first_ec
, true);
1053 /* --------------------------------------------------------------------------
1055 -------------------------------------------------------------------------- */
1056 static struct acpi_ec_query_handler
*
1057 acpi_ec_get_query_handler_by_value(struct acpi_ec
*ec
, u8 value
)
1059 struct acpi_ec_query_handler
*handler
;
1061 mutex_lock(&ec
->mutex
);
1062 list_for_each_entry(handler
, &ec
->list
, node
) {
1063 if (value
== handler
->query_bit
) {
1064 kref_get(&handler
->kref
);
1065 mutex_unlock(&ec
->mutex
);
1069 mutex_unlock(&ec
->mutex
);
1073 static void acpi_ec_query_handler_release(struct kref
*kref
)
1075 struct acpi_ec_query_handler
*handler
=
1076 container_of(kref
, struct acpi_ec_query_handler
, kref
);
1081 static void acpi_ec_put_query_handler(struct acpi_ec_query_handler
*handler
)
1083 kref_put(&handler
->kref
, acpi_ec_query_handler_release
);
1086 int acpi_ec_add_query_handler(struct acpi_ec
*ec
, u8 query_bit
,
1087 acpi_handle handle
, acpi_ec_query_func func
,
1090 struct acpi_ec_query_handler
*handler
=
1091 kzalloc(sizeof(struct acpi_ec_query_handler
), GFP_KERNEL
);
1096 handler
->query_bit
= query_bit
;
1097 handler
->handle
= handle
;
1098 handler
->func
= func
;
1099 handler
->data
= data
;
1100 mutex_lock(&ec
->mutex
);
1101 kref_init(&handler
->kref
);
1102 list_add(&handler
->node
, &ec
->list
);
1103 mutex_unlock(&ec
->mutex
);
1106 EXPORT_SYMBOL_GPL(acpi_ec_add_query_handler
);
1108 static void acpi_ec_remove_query_handlers(struct acpi_ec
*ec
,
1109 bool remove_all
, u8 query_bit
)
1111 struct acpi_ec_query_handler
*handler
, *tmp
;
1112 LIST_HEAD(free_list
);
1114 mutex_lock(&ec
->mutex
);
1115 list_for_each_entry_safe(handler
, tmp
, &ec
->list
, node
) {
1116 if (remove_all
|| query_bit
== handler
->query_bit
) {
1117 list_del_init(&handler
->node
);
1118 list_add(&handler
->node
, &free_list
);
1121 mutex_unlock(&ec
->mutex
);
1122 list_for_each_entry_safe(handler
, tmp
, &free_list
, node
)
1123 acpi_ec_put_query_handler(handler
);
1126 void acpi_ec_remove_query_handler(struct acpi_ec
*ec
, u8 query_bit
)
1128 acpi_ec_remove_query_handlers(ec
, false, query_bit
);
1130 EXPORT_SYMBOL_GPL(acpi_ec_remove_query_handler
);
1132 static struct acpi_ec_query
*acpi_ec_create_query(u8
*pval
)
1134 struct acpi_ec_query
*q
;
1135 struct transaction
*t
;
1137 q
= kzalloc(sizeof (struct acpi_ec_query
), GFP_KERNEL
);
1140 INIT_WORK(&q
->work
, acpi_ec_event_processor
);
1141 t
= &q
->transaction
;
1142 t
->command
= ACPI_EC_COMMAND_QUERY
;
1148 static void acpi_ec_delete_query(struct acpi_ec_query
*q
)
1152 acpi_ec_put_query_handler(q
->handler
);
1157 static void acpi_ec_event_processor(struct work_struct
*work
)
1159 struct acpi_ec_query
*q
= container_of(work
, struct acpi_ec_query
, work
);
1160 struct acpi_ec_query_handler
*handler
= q
->handler
;
1162 ec_dbg_evt("Query(0x%02x) started", handler
->query_bit
);
1164 handler
->func(handler
->data
);
1165 else if (handler
->handle
)
1166 acpi_evaluate_object(handler
->handle
, NULL
, NULL
, NULL
);
1167 ec_dbg_evt("Query(0x%02x) stopped", handler
->query_bit
);
1168 acpi_ec_delete_query(q
);
1171 static int acpi_ec_query(struct acpi_ec
*ec
, u8
*data
)
1175 struct acpi_ec_query
*q
;
1177 q
= acpi_ec_create_query(&value
);
1182 * Query the EC to find out which _Qxx method we need to evaluate.
1183 * Note that successful completion of the query causes the ACPI_EC_SCI
1184 * bit to be cleared (and thus clearing the interrupt source).
1186 result
= acpi_ec_transaction(ec
, &q
->transaction
);
1192 q
->handler
= acpi_ec_get_query_handler_by_value(ec
, value
);
1199 * It is reported that _Qxx are evaluated in a parallel way on
1201 * https://bugzilla.kernel.org/show_bug.cgi?id=94411
1203 * Put this log entry before schedule_work() in order to make
1204 * it appearing before any other log entries occurred during the
1205 * work queue execution.
1207 ec_dbg_evt("Query(0x%02x) scheduled", value
);
1208 if (!queue_work(ec_query_wq
, &q
->work
)) {
1209 ec_dbg_evt("Query(0x%02x) overlapped", value
);
1215 acpi_ec_delete_query(q
);
1221 static void acpi_ec_check_event(struct acpi_ec
*ec
)
1223 unsigned long flags
;
1225 if (ec_event_clearing
== ACPI_EC_EVT_TIMING_EVENT
) {
1227 spin_lock_irqsave(&ec
->lock
, flags
);
1229 * Take care of the SCI_EVT unless no one else is
1230 * taking care of it.
1233 advance_transaction(ec
);
1234 spin_unlock_irqrestore(&ec
->lock
, flags
);
1239 static void acpi_ec_event_handler(struct work_struct
*work
)
1241 unsigned long flags
;
1242 struct acpi_ec
*ec
= container_of(work
, struct acpi_ec
, work
);
1244 ec_dbg_evt("Event started");
1246 spin_lock_irqsave(&ec
->lock
, flags
);
1247 while (ec
->nr_pending_queries
) {
1248 spin_unlock_irqrestore(&ec
->lock
, flags
);
1249 (void)acpi_ec_query(ec
, NULL
);
1250 spin_lock_irqsave(&ec
->lock
, flags
);
1251 ec
->nr_pending_queries
--;
1253 * Before exit, make sure that this work item can be
1254 * scheduled again. There might be QR_EC failures, leaving
1255 * EC_FLAGS_QUERY_PENDING uncleared and preventing this work
1256 * item from being scheduled again.
1258 if (!ec
->nr_pending_queries
) {
1259 if (ec_event_clearing
== ACPI_EC_EVT_TIMING_STATUS
||
1260 ec_event_clearing
== ACPI_EC_EVT_TIMING_QUERY
)
1261 acpi_ec_complete_query(ec
);
1264 spin_unlock_irqrestore(&ec
->lock
, flags
);
1266 ec_dbg_evt("Event stopped");
1268 acpi_ec_check_event(ec
);
1271 static void acpi_ec_handle_interrupt(struct acpi_ec
*ec
)
1273 unsigned long flags
;
1275 spin_lock_irqsave(&ec
->lock
, flags
);
1276 advance_transaction(ec
);
1277 spin_unlock_irqrestore(&ec
->lock
, flags
);
1280 static u32
acpi_ec_gpe_handler(acpi_handle gpe_device
,
1281 u32 gpe_number
, void *data
)
1283 acpi_ec_handle_interrupt(data
);
1284 return ACPI_INTERRUPT_HANDLED
;
1287 static irqreturn_t
acpi_ec_irq_handler(int irq
, void *data
)
1289 acpi_ec_handle_interrupt(data
);
1293 /* --------------------------------------------------------------------------
1294 * Address Space Management
1295 * -------------------------------------------------------------------------- */
1298 acpi_ec_space_handler(u32 function
, acpi_physical_address address
,
1299 u32 bits
, u64
*value64
,
1300 void *handler_context
, void *region_context
)
1302 struct acpi_ec
*ec
= handler_context
;
1303 int result
= 0, i
, bytes
= bits
/ 8;
1304 u8
*value
= (u8
*)value64
;
1306 if ((address
> 0xFF) || !value
|| !handler_context
)
1307 return AE_BAD_PARAMETER
;
1309 if (function
!= ACPI_READ
&& function
!= ACPI_WRITE
)
1310 return AE_BAD_PARAMETER
;
1312 if (ec
->busy_polling
|| bits
> 8)
1313 acpi_ec_burst_enable(ec
);
1315 for (i
= 0; i
< bytes
; ++i
, ++address
, ++value
)
1316 result
= (function
== ACPI_READ
) ?
1317 acpi_ec_read(ec
, address
, value
) :
1318 acpi_ec_write(ec
, address
, *value
);
1320 if (ec
->busy_polling
|| bits
> 8)
1321 acpi_ec_burst_disable(ec
);
1325 return AE_BAD_PARAMETER
;
1327 return AE_NOT_FOUND
;
1335 /* --------------------------------------------------------------------------
1337 * -------------------------------------------------------------------------- */
1340 ec_parse_io_ports(struct acpi_resource
*resource
, void *context
);
1342 static void acpi_ec_free(struct acpi_ec
*ec
)
1351 static struct acpi_ec
*acpi_ec_alloc(void)
1353 struct acpi_ec
*ec
= kzalloc(sizeof(struct acpi_ec
), GFP_KERNEL
);
1357 mutex_init(&ec
->mutex
);
1358 init_waitqueue_head(&ec
->wait
);
1359 INIT_LIST_HEAD(&ec
->list
);
1360 spin_lock_init(&ec
->lock
);
1361 INIT_WORK(&ec
->work
, acpi_ec_event_handler
);
1362 ec
->timestamp
= jiffies
;
1363 ec
->busy_polling
= true;
1364 ec
->polling_guard
= 0;
1371 acpi_ec_register_query_methods(acpi_handle handle
, u32 level
,
1372 void *context
, void **return_value
)
1375 struct acpi_buffer buffer
= { sizeof(node_name
), node_name
};
1376 struct acpi_ec
*ec
= context
;
1380 status
= acpi_get_name(handle
, ACPI_SINGLE_NAME
, &buffer
);
1382 if (ACPI_SUCCESS(status
) && sscanf(node_name
, "_Q%x", &value
) == 1)
1383 acpi_ec_add_query_handler(ec
, value
, handle
, NULL
, NULL
);
1388 ec_parse_device(acpi_handle handle
, u32 Level
, void *context
, void **retval
)
1391 unsigned long long tmp
= 0;
1392 struct acpi_ec
*ec
= context
;
1394 /* clear addr values, ec_parse_io_ports depend on it */
1395 ec
->command_addr
= ec
->data_addr
= 0;
1397 status
= acpi_walk_resources(handle
, METHOD_NAME__CRS
,
1398 ec_parse_io_ports
, ec
);
1399 if (ACPI_FAILURE(status
))
1401 if (ec
->data_addr
== 0 || ec
->command_addr
== 0)
1404 if (boot_ec
&& boot_ec_is_ecdt
&& EC_FLAGS_IGNORE_DSDT_GPE
) {
1406 * Always inherit the GPE number setting from the ECDT
1409 ec
->gpe
= boot_ec
->gpe
;
1411 /* Get GPE bit assignment (EC events). */
1412 /* TODO: Add support for _GPE returning a package */
1413 status
= acpi_evaluate_integer(handle
, "_GPE", NULL
, &tmp
);
1414 if (ACPI_SUCCESS(status
))
1418 * Errors are non-fatal, allowing for ACPI Reduced Hardware
1419 * platforms which use GpioInt instead of GPE.
1422 /* Use the global lock for all EC transactions? */
1424 acpi_evaluate_integer(handle
, "_GLK", NULL
, &tmp
);
1425 ec
->global_lock
= tmp
;
1426 ec
->handle
= handle
;
1427 return AE_CTRL_TERMINATE
;
1430 static bool install_gpe_event_handler(struct acpi_ec
*ec
)
1434 status
= acpi_install_gpe_raw_handler(NULL
, ec
->gpe
,
1435 ACPI_GPE_EDGE_TRIGGERED
,
1436 &acpi_ec_gpe_handler
, ec
);
1437 if (ACPI_FAILURE(status
))
1440 if (test_bit(EC_FLAGS_STARTED
, &ec
->flags
) && ec
->reference_count
>= 1)
1441 acpi_ec_enable_gpe(ec
, true);
1446 static bool install_gpio_irq_event_handler(struct acpi_ec
*ec
)
1448 return request_irq(ec
->irq
, acpi_ec_irq_handler
, IRQF_SHARED
,
1449 "ACPI EC", ec
) >= 0;
1453 * ec_install_handlers - Install service callbacks and register query methods.
1455 * @device: ACPI device object corresponding to @ec.
1457 * Install a handler for the EC address space type unless it has been installed
1458 * already. If @device is not NULL, also look for EC query methods in the
1459 * namespace and register them, and install an event (either GPE or GPIO IRQ)
1460 * handler for the EC, if possible.
1463 * -ENODEV if the address space handler cannot be installed, which means
1464 * "unable to handle transactions",
1465 * -EPROBE_DEFER if GPIO IRQ acquisition needs to be deferred,
1466 * or 0 (success) otherwise.
1468 static int ec_install_handlers(struct acpi_ec
*ec
, struct acpi_device
*device
)
1472 acpi_ec_start(ec
, false);
1474 if (!test_bit(EC_FLAGS_EC_HANDLER_INSTALLED
, &ec
->flags
)) {
1475 acpi_ec_enter_noirq(ec
);
1476 status
= acpi_install_address_space_handler(ec
->handle
,
1478 &acpi_ec_space_handler
,
1480 if (ACPI_FAILURE(status
)) {
1481 acpi_ec_stop(ec
, false);
1484 set_bit(EC_FLAGS_EC_HANDLER_INSTALLED
, &ec
->flags
);
1491 /* ACPI reduced hardware platforms use a GpioInt from _CRS. */
1492 int irq
= acpi_dev_gpio_irq_get(device
, 0);
1494 * Bail out right away for deferred probing or complete the
1495 * initialization regardless of any other errors.
1497 if (irq
== -EPROBE_DEFER
)
1498 return -EPROBE_DEFER
;
1503 if (!test_bit(EC_FLAGS_QUERY_METHODS_INSTALLED
, &ec
->flags
)) {
1504 /* Find and register all query methods */
1505 acpi_walk_namespace(ACPI_TYPE_METHOD
, ec
->handle
, 1,
1506 acpi_ec_register_query_methods
,
1508 set_bit(EC_FLAGS_QUERY_METHODS_INSTALLED
, &ec
->flags
);
1510 if (!test_bit(EC_FLAGS_EVENT_HANDLER_INSTALLED
, &ec
->flags
)) {
1514 ready
= install_gpe_event_handler(ec
);
1515 else if (ec
->irq
>= 0)
1516 ready
= install_gpio_irq_event_handler(ec
);
1519 set_bit(EC_FLAGS_EVENT_HANDLER_INSTALLED
, &ec
->flags
);
1520 acpi_ec_leave_noirq(ec
);
1523 * Failures to install an event handler are not fatal, because
1524 * the EC can be polled for events.
1527 /* EC is fully operational, allow queries */
1528 acpi_ec_enable_event(ec
);
1533 static void ec_remove_handlers(struct acpi_ec
*ec
)
1535 if (test_bit(EC_FLAGS_EC_HANDLER_INSTALLED
, &ec
->flags
)) {
1536 if (ACPI_FAILURE(acpi_remove_address_space_handler(ec
->handle
,
1537 ACPI_ADR_SPACE_EC
, &acpi_ec_space_handler
)))
1538 pr_err("failed to remove space handler\n");
1539 clear_bit(EC_FLAGS_EC_HANDLER_INSTALLED
, &ec
->flags
);
1543 * Stops handling the EC transactions after removing the operation
1544 * region handler. This is required because _REG(DISCONNECT)
1545 * invoked during the removal can result in new EC transactions.
1547 * Flushes the EC requests and thus disables the GPE before
1548 * removing the GPE handler. This is required by the current ACPICA
1549 * GPE core. ACPICA GPE core will automatically disable a GPE when
1550 * it is indicated but there is no way to handle it. So the drivers
1551 * must disable the GPEs prior to removing the GPE handlers.
1553 acpi_ec_stop(ec
, false);
1555 if (test_bit(EC_FLAGS_EVENT_HANDLER_INSTALLED
, &ec
->flags
)) {
1557 ACPI_FAILURE(acpi_remove_gpe_handler(NULL
, ec
->gpe
,
1558 &acpi_ec_gpe_handler
)))
1559 pr_err("failed to remove gpe handler\n");
1562 free_irq(ec
->irq
, ec
);
1564 clear_bit(EC_FLAGS_EVENT_HANDLER_INSTALLED
, &ec
->flags
);
1566 if (test_bit(EC_FLAGS_QUERY_METHODS_INSTALLED
, &ec
->flags
)) {
1567 acpi_ec_remove_query_handlers(ec
, true, 0);
1568 clear_bit(EC_FLAGS_QUERY_METHODS_INSTALLED
, &ec
->flags
);
1572 static int acpi_ec_setup(struct acpi_ec
*ec
, struct acpi_device
*device
)
1576 ret
= ec_install_handlers(ec
, device
);
1580 /* First EC capable of handling transactions */
1584 pr_info("EC_CMD/EC_SC=0x%lx, EC_DATA=0x%lx\n", ec
->command_addr
,
1587 if (test_bit(EC_FLAGS_EVENT_HANDLER_INSTALLED
, &ec
->flags
)) {
1589 pr_info("GPE=0x%x\n", ec
->gpe
);
1591 pr_info("IRQ=%d\n", ec
->irq
);
1597 static bool acpi_ec_ecdt_get_handle(acpi_handle
*phandle
)
1599 struct acpi_table_ecdt
*ecdt_ptr
;
1603 status
= acpi_get_table(ACPI_SIG_ECDT
, 1,
1604 (struct acpi_table_header
**)&ecdt_ptr
);
1605 if (ACPI_FAILURE(status
))
1608 status
= acpi_get_handle(NULL
, ecdt_ptr
->id
, &handle
);
1609 if (ACPI_FAILURE(status
))
1616 static int acpi_ec_add(struct acpi_device
*device
)
1621 strcpy(acpi_device_name(device
), ACPI_EC_DEVICE_NAME
);
1622 strcpy(acpi_device_class(device
), ACPI_EC_CLASS
);
1624 if ((boot_ec
&& boot_ec
->handle
== device
->handle
) ||
1625 !strcmp(acpi_device_hid(device
), ACPI_ECDT_HID
)) {
1626 /* Fast path: this device corresponds to the boot EC. */
1631 ec
= acpi_ec_alloc();
1635 status
= ec_parse_device(device
->handle
, 0, ec
, NULL
);
1636 if (status
!= AE_CTRL_TERMINATE
) {
1641 if (boot_ec
&& ec
->command_addr
== boot_ec
->command_addr
&&
1642 ec
->data_addr
== boot_ec
->data_addr
) {
1643 boot_ec_is_ecdt
= false;
1645 * Trust PNP0C09 namespace location rather than
1646 * ECDT ID. But trust ECDT GPE rather than _GPE
1647 * because of ASUS quirks, so do not change
1648 * boot_ec->gpe to ec->gpe.
1650 boot_ec
->handle
= ec
->handle
;
1651 acpi_handle_debug(ec
->handle
, "duplicated.\n");
1657 ret
= acpi_ec_setup(ec
, device
);
1662 acpi_handle_info(boot_ec
->handle
,
1663 "Boot %s EC used to handle transactions and events\n",
1664 boot_ec_is_ecdt
? "ECDT" : "DSDT");
1666 device
->driver_data
= ec
;
1668 ret
= !!request_region(ec
->data_addr
, 1, "EC data");
1669 WARN(!ret
, "Could not request EC data io port 0x%lx", ec
->data_addr
);
1670 ret
= !!request_region(ec
->command_addr
, 1, "EC cmd");
1671 WARN(!ret
, "Could not request EC cmd io port 0x%lx", ec
->command_addr
);
1673 /* Reprobe devices depending on the EC */
1674 acpi_walk_dep_device_list(ec
->handle
);
1676 acpi_handle_debug(ec
->handle
, "enumerated.\n");
1686 static int acpi_ec_remove(struct acpi_device
*device
)
1693 ec
= acpi_driver_data(device
);
1694 release_region(ec
->data_addr
, 1);
1695 release_region(ec
->command_addr
, 1);
1696 device
->driver_data
= NULL
;
1697 if (ec
!= boot_ec
) {
1698 ec_remove_handlers(ec
);
1705 ec_parse_io_ports(struct acpi_resource
*resource
, void *context
)
1707 struct acpi_ec
*ec
= context
;
1709 if (resource
->type
!= ACPI_RESOURCE_TYPE_IO
)
1713 * The first address region returned is the data port, and
1714 * the second address region returned is the status/command
1717 if (ec
->data_addr
== 0)
1718 ec
->data_addr
= resource
->data
.io
.minimum
;
1719 else if (ec
->command_addr
== 0)
1720 ec
->command_addr
= resource
->data
.io
.minimum
;
1722 return AE_CTRL_TERMINATE
;
1727 static const struct acpi_device_id ec_device_ids
[] = {
1734 * This function is not Windows-compatible as Windows never enumerates the
1735 * namespace EC before the main ACPI device enumeration process. It is
1736 * retained for historical reason and will be deprecated in the future.
1738 void __init
acpi_ec_dsdt_probe(void)
1745 * If a platform has ECDT, there is no need to proceed as the
1746 * following probe is not a part of the ACPI device enumeration,
1747 * executing _STA is not safe, and thus this probe may risk of
1748 * picking up an invalid EC device.
1753 ec
= acpi_ec_alloc();
1758 * At this point, the namespace is initialized, so start to find
1759 * the namespace objects.
1761 status
= acpi_get_devices(ec_device_ids
[0].id
, ec_parse_device
, ec
, NULL
);
1762 if (ACPI_FAILURE(status
) || !ec
->handle
) {
1768 * When the DSDT EC is available, always re-configure boot EC to
1769 * have _REG evaluated. _REG can only be evaluated after the
1770 * namespace initialization.
1771 * At this point, the GPE is not fully initialized, so do not to
1772 * handle the events.
1774 ret
= acpi_ec_setup(ec
, NULL
);
1782 acpi_handle_info(ec
->handle
,
1783 "Boot DSDT EC used to handle transactions\n");
1787 * If the DSDT EC is not functioning, we still need to prepare a fully
1788 * functioning ECDT EC first in order to handle the events.
1789 * https://bugzilla.kernel.org/show_bug.cgi?id=115021
1791 static int __init
acpi_ec_ecdt_start(void)
1797 /* In case acpi_ec_ecdt_start() is called after acpi_ec_add() */
1798 if (!boot_ec_is_ecdt
)
1802 * At this point, the namespace and the GPE is initialized, so
1803 * start to find the namespace objects and handle the events.
1805 * Note: ec->handle can be valid if this function is called after
1806 * acpi_ec_add(), hence the fast path.
1808 if (boot_ec
->handle
== ACPI_ROOT_OBJECT
) {
1809 if (!acpi_ec_ecdt_get_handle(&handle
))
1811 boot_ec
->handle
= handle
;
1814 /* Register to ACPI bus with PM ops attached */
1815 return acpi_bus_register_early_device(ACPI_BUS_TYPE_ECDT_EC
);
1820 * Some EC firmware variations refuses to respond QR_EC when SCI_EVT is not
1821 * set, for which case, we complete the QR_EC without issuing it to the
1823 * https://bugzilla.kernel.org/show_bug.cgi?id=82611
1824 * https://bugzilla.kernel.org/show_bug.cgi?id=97381
1826 static int ec_flag_query_handshake(const struct dmi_system_id
*id
)
1828 pr_debug("Detected the EC firmware requiring QR_EC issued when SCI_EVT set\n");
1829 EC_FLAGS_QUERY_HANDSHAKE
= 1;
1835 * On some hardware it is necessary to clear events accumulated by the EC during
1836 * sleep. These ECs stop reporting GPEs until they are manually polled, if too
1837 * many events are accumulated. (e.g. Samsung Series 5/9 notebooks)
1839 * https://bugzilla.kernel.org/show_bug.cgi?id=44161
1841 * Ideally, the EC should also be instructed NOT to accumulate events during
1842 * sleep (which Windows seems to do somehow), but the interface to control this
1843 * behaviour is not known at this time.
1845 * Models known to be affected are Samsung 530Uxx/535Uxx/540Uxx/550Pxx/900Xxx,
1846 * however it is very likely that other Samsung models are affected.
1848 * On systems which don't accumulate _Q events during sleep, this extra check
1849 * should be harmless.
1851 static int ec_clear_on_resume(const struct dmi_system_id
*id
)
1853 pr_debug("Detected system needing EC poll on resume.\n");
1854 EC_FLAGS_CLEAR_ON_RESUME
= 1;
1855 ec_event_clearing
= ACPI_EC_EVT_TIMING_STATUS
;
1860 * Some ECDTs contain wrong register addresses.
1862 * https://bugzilla.kernel.org/show_bug.cgi?id=12461
1864 static int ec_correct_ecdt(const struct dmi_system_id
*id
)
1866 pr_debug("Detected system needing ECDT address correction.\n");
1867 EC_FLAGS_CORRECT_ECDT
= 1;
1872 * Some DSDTs contain wrong GPE setting.
1873 * Asus FX502VD/VE, GL702VMK, X550VXK, X580VD
1874 * https://bugzilla.kernel.org/show_bug.cgi?id=195651
1876 static int ec_honor_ecdt_gpe(const struct dmi_system_id
*id
)
1878 pr_debug("Detected system needing ignore DSDT GPE setting.\n");
1879 EC_FLAGS_IGNORE_DSDT_GPE
= 1;
1883 static const struct dmi_system_id ec_dmi_table
[] __initconst
= {
1885 ec_correct_ecdt
, "MSI MS-171F", {
1886 DMI_MATCH(DMI_SYS_VENDOR
, "Micro-Star"),
1887 DMI_MATCH(DMI_PRODUCT_NAME
, "MS-171F"),}, NULL
},
1889 ec_honor_ecdt_gpe
, "ASUS FX502VD", {
1890 DMI_MATCH(DMI_SYS_VENDOR
, "ASUSTeK COMPUTER INC."),
1891 DMI_MATCH(DMI_PRODUCT_NAME
, "FX502VD"),}, NULL
},
1893 ec_honor_ecdt_gpe
, "ASUS FX502VE", {
1894 DMI_MATCH(DMI_SYS_VENDOR
, "ASUSTeK COMPUTER INC."),
1895 DMI_MATCH(DMI_PRODUCT_NAME
, "FX502VE"),}, NULL
},
1897 ec_honor_ecdt_gpe
, "ASUS GL702VMK", {
1898 DMI_MATCH(DMI_SYS_VENDOR
, "ASUSTeK COMPUTER INC."),
1899 DMI_MATCH(DMI_PRODUCT_NAME
, "GL702VMK"),}, NULL
},
1901 ec_honor_ecdt_gpe
, "ASUS X550VXK", {
1902 DMI_MATCH(DMI_SYS_VENDOR
, "ASUSTeK COMPUTER INC."),
1903 DMI_MATCH(DMI_PRODUCT_NAME
, "X550VXK"),}, NULL
},
1905 ec_honor_ecdt_gpe
, "ASUS X580VD", {
1906 DMI_MATCH(DMI_SYS_VENDOR
, "ASUSTeK COMPUTER INC."),
1907 DMI_MATCH(DMI_PRODUCT_NAME
, "X580VD"),}, NULL
},
1909 ec_clear_on_resume
, "Samsung hardware", {
1910 DMI_MATCH(DMI_SYS_VENDOR
, "SAMSUNG ELECTRONICS CO., LTD.")}, NULL
},
1914 void __init
acpi_ec_ecdt_probe(void)
1916 struct acpi_table_ecdt
*ecdt_ptr
;
1921 /* Generate a boot ec context. */
1922 dmi_check_system(ec_dmi_table
);
1923 status
= acpi_get_table(ACPI_SIG_ECDT
, 1,
1924 (struct acpi_table_header
**)&ecdt_ptr
);
1925 if (ACPI_FAILURE(status
))
1928 if (!ecdt_ptr
->control
.address
|| !ecdt_ptr
->data
.address
) {
1931 * https://bugzilla.kernel.org/show_bug.cgi?id=11880
1936 ec
= acpi_ec_alloc();
1940 if (EC_FLAGS_CORRECT_ECDT
) {
1941 ec
->command_addr
= ecdt_ptr
->data
.address
;
1942 ec
->data_addr
= ecdt_ptr
->control
.address
;
1944 ec
->command_addr
= ecdt_ptr
->control
.address
;
1945 ec
->data_addr
= ecdt_ptr
->data
.address
;
1949 * Ignore the GPE value on Reduced Hardware platforms.
1950 * Some products have this set to an erroneous value.
1952 if (!acpi_gbl_reduced_hardware
)
1953 ec
->gpe
= ecdt_ptr
->gpe
;
1955 ec
->handle
= ACPI_ROOT_OBJECT
;
1958 * At this point, the namespace is not initialized, so do not find
1959 * the namespace objects, or handle the events.
1961 ret
= acpi_ec_setup(ec
, NULL
);
1968 boot_ec_is_ecdt
= true;
1970 pr_info("Boot ECDT EC used to handle transactions\n");
1973 #ifdef CONFIG_PM_SLEEP
1974 static int acpi_ec_suspend(struct device
*dev
)
1976 struct acpi_ec
*ec
=
1977 acpi_driver_data(to_acpi_device(dev
));
1979 if (!pm_suspend_no_platform() && ec_freeze_events
)
1980 acpi_ec_disable_event(ec
);
1984 static int acpi_ec_suspend_noirq(struct device
*dev
)
1986 struct acpi_ec
*ec
= acpi_driver_data(to_acpi_device(dev
));
1989 * The SCI handler doesn't run at this point, so the GPE can be
1990 * masked at the low level without side effects.
1992 if (ec_no_wakeup
&& test_bit(EC_FLAGS_STARTED
, &ec
->flags
) &&
1993 ec
->gpe
>= 0 && ec
->reference_count
>= 1)
1994 acpi_set_gpe(NULL
, ec
->gpe
, ACPI_GPE_DISABLE
);
1996 acpi_ec_enter_noirq(ec
);
2001 static int acpi_ec_resume_noirq(struct device
*dev
)
2003 struct acpi_ec
*ec
= acpi_driver_data(to_acpi_device(dev
));
2005 acpi_ec_leave_noirq(ec
);
2007 if (ec_no_wakeup
&& test_bit(EC_FLAGS_STARTED
, &ec
->flags
) &&
2008 ec
->gpe
>= 0 && ec
->reference_count
>= 1)
2009 acpi_set_gpe(NULL
, ec
->gpe
, ACPI_GPE_ENABLE
);
2014 static int acpi_ec_resume(struct device
*dev
)
2016 struct acpi_ec
*ec
=
2017 acpi_driver_data(to_acpi_device(dev
));
2019 acpi_ec_enable_event(ec
);
2023 void acpi_ec_mark_gpe_for_wake(void)
2025 if (first_ec
&& !ec_no_wakeup
)
2026 acpi_mark_gpe_for_wake(NULL
, first_ec
->gpe
);
2028 EXPORT_SYMBOL_GPL(acpi_ec_mark_gpe_for_wake
);
2030 void acpi_ec_set_gpe_wake_mask(u8 action
)
2032 if (pm_suspend_no_platform() && first_ec
&& !ec_no_wakeup
)
2033 acpi_set_gpe_wake_mask(NULL
, first_ec
->gpe
, action
);
2036 bool acpi_ec_dispatch_gpe(void)
2043 ret
= acpi_dispatch_gpe(NULL
, first_ec
->gpe
);
2044 if (ret
== ACPI_INTERRUPT_HANDLED
) {
2045 pm_pr_dbg("EC GPE dispatched\n");
2050 #endif /* CONFIG_PM_SLEEP */
2052 static const struct dev_pm_ops acpi_ec_pm
= {
2053 SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(acpi_ec_suspend_noirq
, acpi_ec_resume_noirq
)
2054 SET_SYSTEM_SLEEP_PM_OPS(acpi_ec_suspend
, acpi_ec_resume
)
2057 static int param_set_event_clearing(const char *val
,
2058 const struct kernel_param
*kp
)
2062 if (!strncmp(val
, "status", sizeof("status") - 1)) {
2063 ec_event_clearing
= ACPI_EC_EVT_TIMING_STATUS
;
2064 pr_info("Assuming SCI_EVT clearing on EC_SC accesses\n");
2065 } else if (!strncmp(val
, "query", sizeof("query") - 1)) {
2066 ec_event_clearing
= ACPI_EC_EVT_TIMING_QUERY
;
2067 pr_info("Assuming SCI_EVT clearing on QR_EC writes\n");
2068 } else if (!strncmp(val
, "event", sizeof("event") - 1)) {
2069 ec_event_clearing
= ACPI_EC_EVT_TIMING_EVENT
;
2070 pr_info("Assuming SCI_EVT clearing on event reads\n");
2076 static int param_get_event_clearing(char *buffer
,
2077 const struct kernel_param
*kp
)
2079 switch (ec_event_clearing
) {
2080 case ACPI_EC_EVT_TIMING_STATUS
:
2081 return sprintf(buffer
, "status");
2082 case ACPI_EC_EVT_TIMING_QUERY
:
2083 return sprintf(buffer
, "query");
2084 case ACPI_EC_EVT_TIMING_EVENT
:
2085 return sprintf(buffer
, "event");
2087 return sprintf(buffer
, "invalid");
2092 module_param_call(ec_event_clearing
, param_set_event_clearing
, param_get_event_clearing
,
2094 MODULE_PARM_DESC(ec_event_clearing
, "Assumed SCI_EVT clearing timing");
2096 static struct acpi_driver acpi_ec_driver
= {
2098 .class = ACPI_EC_CLASS
,
2099 .ids
= ec_device_ids
,
2102 .remove
= acpi_ec_remove
,
2104 .drv
.pm
= &acpi_ec_pm
,
2107 static void acpi_ec_destroy_workqueues(void)
2110 destroy_workqueue(ec_wq
);
2114 destroy_workqueue(ec_query_wq
);
2119 static int acpi_ec_init_workqueues(void)
2122 ec_wq
= alloc_ordered_workqueue("kec", 0);
2125 ec_query_wq
= alloc_workqueue("kec_query", 0, ec_max_queries
);
2127 if (!ec_wq
|| !ec_query_wq
) {
2128 acpi_ec_destroy_workqueues();
2134 static const struct dmi_system_id acpi_ec_no_wakeup
[] = {
2136 .ident
= "Thinkpad X1 Carbon 6th",
2138 DMI_MATCH(DMI_SYS_VENDOR
, "LENOVO"),
2139 DMI_MATCH(DMI_PRODUCT_FAMILY
, "Thinkpad X1 Carbon 6th"),
2143 .ident
= "ThinkPad X1 Carbon 6th",
2145 DMI_MATCH(DMI_SYS_VENDOR
, "LENOVO"),
2146 DMI_MATCH(DMI_PRODUCT_FAMILY
, "ThinkPad X1 Carbon 6th"),
2150 .ident
= "ThinkPad X1 Yoga 3rd",
2152 DMI_MATCH(DMI_SYS_VENDOR
, "LENOVO"),
2153 DMI_MATCH(DMI_PRODUCT_FAMILY
, "ThinkPad X1 Yoga 3rd"),
2159 int __init
acpi_ec_init(void)
2162 int ecdt_fail
, dsdt_fail
;
2164 result
= acpi_ec_init_workqueues();
2169 * Disable EC wakeup on following systems to prevent periodic
2170 * wakeup from EC GPE.
2172 if (dmi_check_system(acpi_ec_no_wakeup
)) {
2173 ec_no_wakeup
= true;
2174 pr_debug("Disabling EC wakeup on suspend-to-idle\n");
2177 /* Drivers must be started after acpi_ec_query_init() */
2178 dsdt_fail
= acpi_bus_register_driver(&acpi_ec_driver
);
2180 * Register ECDT to ACPI bus only when PNP0C09 probe fails. This is
2181 * useful for platforms (confirmed on ASUS X550ZE) with valid ECDT
2182 * settings but invalid DSDT settings.
2183 * https://bugzilla.kernel.org/show_bug.cgi?id=196847
2185 ecdt_fail
= acpi_ec_ecdt_start();
2186 return ecdt_fail
&& dsdt_fail
? -ENODEV
: 0;
2189 /* EC driver currently not unloadable */
2191 static void __exit
acpi_ec_exit(void)
2194 acpi_bus_unregister_driver(&acpi_ec_driver
);
2195 acpi_ec_destroy_workqueues();