2 * ec.c - ACPI Embedded Controller Driver (v3)
4 * Copyright (C) 2001-2015 Intel Corporation
5 * Author: 2014, 2015 Lv Zheng <lv.zheng@intel.com>
6 * 2006, 2007 Alexey Starikovskiy <alexey.y.starikovskiy@intel.com>
7 * 2006 Denis Sadykov <denis.m.sadykov@intel.com>
8 * 2004 Luming Yu <luming.yu@intel.com>
9 * 2001, 2002 Andy Grover <andrew.grover@intel.com>
10 * 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
11 * Copyright (C) 2008 Alexey Starikovskiy <astarikovskiy@suse.de>
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 * You should have received a copy of the GNU General Public License along
26 * with this program; if not, write to the Free Software Foundation, Inc.,
27 * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
29 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
32 /* Uncomment next line to get verbose printout */
34 #define pr_fmt(fmt) "ACPI : EC: " fmt
36 #include <linux/kernel.h>
37 #include <linux/module.h>
38 #include <linux/init.h>
39 #include <linux/types.h>
40 #include <linux/delay.h>
41 #include <linux/interrupt.h>
42 #include <linux/list.h>
43 #include <linux/spinlock.h>
44 #include <linux/slab.h>
45 #include <linux/acpi.h>
46 #include <linux/dmi.h>
51 #define ACPI_EC_CLASS "embedded_controller"
52 #define ACPI_EC_DEVICE_NAME "Embedded Controller"
53 #define ACPI_EC_FILE_INFO "info"
55 /* EC status register */
56 #define ACPI_EC_FLAG_OBF 0x01 /* Output buffer full */
57 #define ACPI_EC_FLAG_IBF 0x02 /* Input buffer full */
58 #define ACPI_EC_FLAG_CMD 0x08 /* Input buffer contains a command */
59 #define ACPI_EC_FLAG_BURST 0x10 /* burst mode */
60 #define ACPI_EC_FLAG_SCI 0x20 /* EC-SCI occurred */
64 ACPI_EC_COMMAND_READ = 0x80,
65 ACPI_EC_COMMAND_WRITE = 0x81,
66 ACPI_EC_BURST_ENABLE = 0x82,
67 ACPI_EC_BURST_DISABLE = 0x83,
68 ACPI_EC_COMMAND_QUERY = 0x84,
71 #define ACPI_EC_DELAY 500 /* Wait 500ms max. during EC ops */
72 #define ACPI_EC_UDELAY_GLK 1000 /* Wait 1ms max. to get global lock */
73 #define ACPI_EC_MSI_UDELAY 550 /* Wait 550us for MSI EC */
74 #define ACPI_EC_UDELAY_POLL 1000 /* Wait 1ms for EC transaction polling */
75 #define ACPI_EC_CLEAR_MAX 100 /* Maximum number of events to query
76 * when trying to clear the EC */
79 EC_FLAGS_QUERY_PENDING, /* Query is pending */
80 EC_FLAGS_HANDLERS_INSTALLED, /* Handlers for GPE and
81 * OpReg are installed */
82 EC_FLAGS_STARTED, /* Driver is started */
83 EC_FLAGS_STOPPED, /* Driver is stopped */
84 EC_FLAGS_COMMAND_STORM, /* GPE storms occurred to the
85 * current command processing */
88 #define ACPI_EC_COMMAND_POLL 0x01 /* Available for command byte */
89 #define ACPI_EC_COMMAND_COMPLETE 0x02 /* Completed last byte */
91 /* ec.c is compiled in acpi namespace so this shows up as acpi.ec_delay param */
92 static unsigned int ec_delay __read_mostly = ACPI_EC_DELAY;
93 module_param(ec_delay, uint, 0644);
94 MODULE_PARM_DESC(ec_delay, "Timeout(ms) waited until an EC command completes");
97 * If the number of false interrupts per one transaction exceeds
98 * this threshold, will think there is a GPE storm happened and
99 * will disable the GPE for normal transaction.
101 static unsigned int ec_storm_threshold __read_mostly = 8;
102 module_param(ec_storm_threshold, uint, 0644);
103 MODULE_PARM_DESC(ec_storm_threshold, "Maxim false GPE numbers not considered as GPE storm");
105 struct acpi_ec_query_handler {
106 struct list_head node;
107 acpi_ec_query_func func;
117 unsigned short irq_count;
124 unsigned long timestamp;
127 static int acpi_ec_query(struct acpi_ec *ec, u8 *data);
128 static void advance_transaction(struct acpi_ec *ec);
130 struct acpi_ec *boot_ec, *first_ec;
131 EXPORT_SYMBOL(first_ec);
133 static int EC_FLAGS_MSI; /* Out-of-spec MSI controller */
134 static int EC_FLAGS_VALIDATE_ECDT; /* ASUStec ECDTs need to be validated */
135 static int EC_FLAGS_SKIP_DSDT_SCAN; /* Not all BIOS survive early DSDT scan */
136 static int EC_FLAGS_CLEAR_ON_RESUME; /* Needs acpi_ec_clear() on boot/resume */
137 static int EC_FLAGS_QUERY_HANDSHAKE; /* Needs QR_EC issued when SCI_EVT set */
139 /* --------------------------------------------------------------------------
141 * -------------------------------------------------------------------------- */
144 * Splitters used by the developers to track the boundary of the EC
145 * handling processes.
148 #define EC_DBG_SEP " "
149 #define EC_DBG_DRV "+++++"
150 #define EC_DBG_STM "====="
151 #define EC_DBG_REQ "*****"
152 #define EC_DBG_EVT "#####"
154 #define EC_DBG_SEP ""
161 #define ec_log_raw(fmt, ...) \
162 pr_info(fmt "\n", ##__VA_ARGS__)
163 #define ec_dbg_raw(fmt, ...) \
164 pr_debug(fmt "\n", ##__VA_ARGS__)
165 #define ec_log(filter, fmt, ...) \
166 ec_log_raw(filter EC_DBG_SEP fmt EC_DBG_SEP filter, ##__VA_ARGS__)
167 #define ec_dbg(filter, fmt, ...) \
168 ec_dbg_raw(filter EC_DBG_SEP fmt EC_DBG_SEP filter, ##__VA_ARGS__)
170 #define ec_log_drv(fmt, ...) \
171 ec_log(EC_DBG_DRV, fmt, ##__VA_ARGS__)
172 #define ec_dbg_drv(fmt, ...) \
173 ec_dbg(EC_DBG_DRV, fmt, ##__VA_ARGS__)
174 #define ec_dbg_stm(fmt, ...) \
175 ec_dbg(EC_DBG_STM, fmt, ##__VA_ARGS__)
176 #define ec_dbg_req(fmt, ...) \
177 ec_dbg(EC_DBG_REQ, fmt, ##__VA_ARGS__)
178 #define ec_dbg_evt(fmt, ...) \
179 ec_dbg(EC_DBG_EVT, fmt, ##__VA_ARGS__)
181 /* --------------------------------------------------------------------------
183 * -------------------------------------------------------------------------- */
185 static bool acpi_ec_started(struct acpi_ec *ec)
187 return test_bit(EC_FLAGS_STARTED, &ec->flags) &&
188 !test_bit(EC_FLAGS_STOPPED, &ec->flags);
191 static bool acpi_ec_flushed(struct acpi_ec *ec)
193 return ec->reference_count == 1;
196 /* --------------------------------------------------------------------------
198 * -------------------------------------------------------------------------- */
200 static inline u8 acpi_ec_read_status(struct acpi_ec *ec)
202 u8 x = inb(ec->command_addr);
204 ec_dbg_raw("EC_SC(R) = 0x%2.2x "
205 "SCI_EVT=%d BURST=%d CMD=%d IBF=%d OBF=%d",
207 !!(x & ACPI_EC_FLAG_SCI),
208 !!(x & ACPI_EC_FLAG_BURST),
209 !!(x & ACPI_EC_FLAG_CMD),
210 !!(x & ACPI_EC_FLAG_IBF),
211 !!(x & ACPI_EC_FLAG_OBF));
215 static inline u8 acpi_ec_read_data(struct acpi_ec *ec)
217 u8 x = inb(ec->data_addr);
219 ec->curr->timestamp = jiffies;
220 ec_dbg_raw("EC_DATA(R) = 0x%2.2x", x);
224 static inline void acpi_ec_write_cmd(struct acpi_ec *ec, u8 command)
226 ec_dbg_raw("EC_SC(W) = 0x%2.2x", command);
227 outb(command, ec->command_addr);
228 ec->curr->timestamp = jiffies;
231 static inline void acpi_ec_write_data(struct acpi_ec *ec, u8 data)
233 ec_dbg_raw("EC_DATA(W) = 0x%2.2x", data);
234 outb(data, ec->data_addr);
235 ec->curr->timestamp = jiffies;
239 static const char *acpi_ec_cmd_string(u8 cmd)
256 #define acpi_ec_cmd_string(cmd) "UNDEF"
259 /* --------------------------------------------------------------------------
261 * -------------------------------------------------------------------------- */
263 static inline bool acpi_ec_is_gpe_raised(struct acpi_ec *ec)
265 acpi_event_status gpe_status = 0;
267 (void)acpi_get_gpe_status(NULL, ec->gpe, &gpe_status);
268 return (gpe_status & ACPI_EVENT_FLAG_SET) ? true : false;
271 static inline void acpi_ec_enable_gpe(struct acpi_ec *ec, bool open)
274 acpi_enable_gpe(NULL, ec->gpe);
276 BUG_ON(ec->reference_count < 1);
277 acpi_set_gpe(NULL, ec->gpe, ACPI_GPE_ENABLE);
279 if (acpi_ec_is_gpe_raised(ec)) {
281 * On some platforms, EN=1 writes cannot trigger GPE. So
282 * software need to manually trigger a pseudo GPE event on
285 ec_dbg_raw("Polling quirk");
286 advance_transaction(ec);
290 static inline void acpi_ec_disable_gpe(struct acpi_ec *ec, bool close)
293 acpi_disable_gpe(NULL, ec->gpe);
295 BUG_ON(ec->reference_count < 1);
296 acpi_set_gpe(NULL, ec->gpe, ACPI_GPE_DISABLE);
300 static inline void acpi_ec_clear_gpe(struct acpi_ec *ec)
303 * GPE STS is a W1C register, which means:
304 * 1. Software can clear it without worrying about clearing other
305 * GPEs' STS bits when the hardware sets them in parallel.
306 * 2. As long as software can ensure only clearing it when it is
307 * set, hardware won't set it in parallel.
308 * So software can clear GPE in any contexts.
309 * Warning: do not move the check into advance_transaction() as the
310 * EC commands will be sent without GPE raised.
312 if (!acpi_ec_is_gpe_raised(ec))
314 acpi_clear_gpe(NULL, ec->gpe);
317 /* --------------------------------------------------------------------------
318 * Transaction Management
319 * -------------------------------------------------------------------------- */
321 static void acpi_ec_submit_request(struct acpi_ec *ec)
323 ec->reference_count++;
324 if (ec->reference_count == 1)
325 acpi_ec_enable_gpe(ec, true);
328 static void acpi_ec_complete_request(struct acpi_ec *ec)
330 bool flushed = false;
332 ec->reference_count--;
333 if (ec->reference_count == 0)
334 acpi_ec_disable_gpe(ec, true);
335 flushed = acpi_ec_flushed(ec);
340 static void acpi_ec_set_storm(struct acpi_ec *ec, u8 flag)
342 if (!test_bit(flag, &ec->flags)) {
343 acpi_ec_disable_gpe(ec, false);
344 ec_dbg_drv("Polling enabled");
345 set_bit(flag, &ec->flags);
349 static void acpi_ec_clear_storm(struct acpi_ec *ec, u8 flag)
351 if (test_bit(flag, &ec->flags)) {
352 clear_bit(flag, &ec->flags);
353 acpi_ec_enable_gpe(ec, false);
354 ec_dbg_drv("Polling disabled");
359 * acpi_ec_submit_flushable_request() - Increase the reference count unless
360 * the flush operation is not in
364 * This function must be used before taking a new action that should hold
365 * the reference count. If this function returns false, then the action
366 * must be discarded or it will prevent the flush operation from being
369 static bool acpi_ec_submit_flushable_request(struct acpi_ec *ec)
371 if (!acpi_ec_started(ec))
373 acpi_ec_submit_request(ec);
377 static void acpi_ec_submit_query(struct acpi_ec *ec)
379 if (!test_and_set_bit(EC_FLAGS_QUERY_PENDING, &ec->flags)) {
380 ec_dbg_req("Event started");
381 schedule_work(&ec->work);
385 static void acpi_ec_complete_query(struct acpi_ec *ec)
387 if (ec->curr->command == ACPI_EC_COMMAND_QUERY) {
388 clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags);
389 ec_dbg_req("Event stopped");
393 static int ec_transaction_completed(struct acpi_ec *ec)
398 spin_lock_irqsave(&ec->lock, flags);
399 if (ec->curr && (ec->curr->flags & ACPI_EC_COMMAND_COMPLETE))
401 spin_unlock_irqrestore(&ec->lock, flags);
405 static void advance_transaction(struct acpi_ec *ec)
407 struct transaction *t;
411 ec_dbg_stm("%s (%d)", in_interrupt() ? "IRQ" : "TASK",
414 * By always clearing STS before handling all indications, we can
415 * ensure a hardware STS 0->1 change after this clearing can always
416 * trigger a GPE interrupt.
418 acpi_ec_clear_gpe(ec);
419 status = acpi_ec_read_status(ec);
423 if (t->flags & ACPI_EC_COMMAND_POLL) {
424 if (t->wlen > t->wi) {
425 if ((status & ACPI_EC_FLAG_IBF) == 0)
426 acpi_ec_write_data(ec, t->wdata[t->wi++]);
429 } else if (t->rlen > t->ri) {
430 if ((status & ACPI_EC_FLAG_OBF) == 1) {
431 t->rdata[t->ri++] = acpi_ec_read_data(ec);
432 if (t->rlen == t->ri) {
433 t->flags |= ACPI_EC_COMMAND_COMPLETE;
434 if (t->command == ACPI_EC_COMMAND_QUERY)
435 ec_dbg_req("Command(%s) hardware completion",
436 acpi_ec_cmd_string(t->command));
441 } else if (t->wlen == t->wi &&
442 (status & ACPI_EC_FLAG_IBF) == 0) {
443 t->flags |= ACPI_EC_COMMAND_COMPLETE;
448 if (EC_FLAGS_QUERY_HANDSHAKE &&
449 !(status & ACPI_EC_FLAG_SCI) &&
450 (t->command == ACPI_EC_COMMAND_QUERY)) {
451 t->flags |= ACPI_EC_COMMAND_POLL;
452 acpi_ec_complete_query(ec);
453 t->rdata[t->ri++] = 0x00;
454 t->flags |= ACPI_EC_COMMAND_COMPLETE;
455 ec_dbg_req("Command(%s) software completion",
456 acpi_ec_cmd_string(t->command));
458 } else if ((status & ACPI_EC_FLAG_IBF) == 0) {
459 acpi_ec_write_cmd(ec, t->command);
460 t->flags |= ACPI_EC_COMMAND_POLL;
461 acpi_ec_complete_query(ec);
468 * If SCI bit is set, then don't think it's a false IRQ
469 * otherwise will take a not handled IRQ as a false one.
471 if (!(status & ACPI_EC_FLAG_SCI)) {
472 if (in_interrupt() && t) {
473 if (t->irq_count < ec_storm_threshold)
475 /* Allow triggering on 0 threshold */
476 if (t->irq_count == ec_storm_threshold)
477 acpi_ec_set_storm(ec, EC_FLAGS_COMMAND_STORM);
481 if (status & ACPI_EC_FLAG_SCI)
482 acpi_ec_submit_query(ec);
483 if (wakeup && in_interrupt())
487 static void start_transaction(struct acpi_ec *ec)
489 ec->curr->irq_count = ec->curr->wi = ec->curr->ri = 0;
491 ec->curr->timestamp = jiffies;
492 advance_transaction(ec);
495 static int ec_poll(struct acpi_ec *ec)
498 int repeat = 5; /* number of command restarts */
501 unsigned long delay = jiffies +
502 msecs_to_jiffies(ec_delay);
503 unsigned long usecs = ACPI_EC_UDELAY_POLL;
505 /* don't sleep with disabled interrupts */
506 if (EC_FLAGS_MSI || irqs_disabled()) {
507 usecs = ACPI_EC_MSI_UDELAY;
509 if (ec_transaction_completed(ec))
512 if (wait_event_timeout(ec->wait,
513 ec_transaction_completed(ec),
514 usecs_to_jiffies(usecs)))
517 spin_lock_irqsave(&ec->lock, flags);
518 if (time_after(jiffies,
519 ec->curr->timestamp +
520 usecs_to_jiffies(usecs)))
521 advance_transaction(ec);
522 spin_unlock_irqrestore(&ec->lock, flags);
523 } while (time_before(jiffies, delay));
524 pr_debug("controller reset, restart transaction\n");
525 spin_lock_irqsave(&ec->lock, flags);
526 start_transaction(ec);
527 spin_unlock_irqrestore(&ec->lock, flags);
532 static int acpi_ec_transaction_unlocked(struct acpi_ec *ec,
533 struct transaction *t)
539 udelay(ACPI_EC_MSI_UDELAY);
540 /* start transaction */
541 spin_lock_irqsave(&ec->lock, tmp);
542 /* Enable GPE for command processing (IBF=0/OBF=1) */
543 if (!acpi_ec_submit_flushable_request(ec)) {
547 /* following two actions should be kept atomic */
549 ec_dbg_req("Command(%s) started", acpi_ec_cmd_string(t->command));
550 start_transaction(ec);
551 spin_unlock_irqrestore(&ec->lock, tmp);
553 spin_lock_irqsave(&ec->lock, tmp);
554 if (t->irq_count == ec_storm_threshold)
555 acpi_ec_clear_storm(ec, EC_FLAGS_COMMAND_STORM);
556 ec_dbg_req("Command(%s) stopped", acpi_ec_cmd_string(t->command));
558 /* Disable GPE for command processing (IBF=0/OBF=1) */
559 acpi_ec_complete_request(ec);
561 spin_unlock_irqrestore(&ec->lock, tmp);
565 static int acpi_ec_transaction(struct acpi_ec *ec, struct transaction *t)
570 if (!ec || (!t) || (t->wlen && !t->wdata) || (t->rlen && !t->rdata))
573 memset(t->rdata, 0, t->rlen);
574 mutex_lock(&ec->mutex);
575 if (ec->global_lock) {
576 status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk);
577 if (ACPI_FAILURE(status)) {
583 status = acpi_ec_transaction_unlocked(ec, t);
585 if (test_bit(EC_FLAGS_COMMAND_STORM, &ec->flags))
588 acpi_release_global_lock(glk);
590 mutex_unlock(&ec->mutex);
594 static int acpi_ec_burst_enable(struct acpi_ec *ec)
597 struct transaction t = {.command = ACPI_EC_BURST_ENABLE,
598 .wdata = NULL, .rdata = &d,
599 .wlen = 0, .rlen = 1};
601 return acpi_ec_transaction(ec, &t);
604 static int acpi_ec_burst_disable(struct acpi_ec *ec)
606 struct transaction t = {.command = ACPI_EC_BURST_DISABLE,
607 .wdata = NULL, .rdata = NULL,
608 .wlen = 0, .rlen = 0};
610 return (acpi_ec_read_status(ec) & ACPI_EC_FLAG_BURST) ?
611 acpi_ec_transaction(ec, &t) : 0;
614 static int acpi_ec_read(struct acpi_ec *ec, u8 address, u8 *data)
618 struct transaction t = {.command = ACPI_EC_COMMAND_READ,
619 .wdata = &address, .rdata = &d,
620 .wlen = 1, .rlen = 1};
622 result = acpi_ec_transaction(ec, &t);
627 static int acpi_ec_write(struct acpi_ec *ec, u8 address, u8 data)
629 u8 wdata[2] = { address, data };
630 struct transaction t = {.command = ACPI_EC_COMMAND_WRITE,
631 .wdata = wdata, .rdata = NULL,
632 .wlen = 2, .rlen = 0};
634 return acpi_ec_transaction(ec, &t);
637 int ec_read(u8 addr, u8 *val)
645 err = acpi_ec_read(first_ec, addr, &temp_data);
653 EXPORT_SYMBOL(ec_read);
655 int ec_write(u8 addr, u8 val)
662 err = acpi_ec_write(first_ec, addr, val);
666 EXPORT_SYMBOL(ec_write);
668 int ec_transaction(u8 command,
669 const u8 *wdata, unsigned wdata_len,
670 u8 *rdata, unsigned rdata_len)
672 struct transaction t = {.command = command,
673 .wdata = wdata, .rdata = rdata,
674 .wlen = wdata_len, .rlen = rdata_len};
679 return acpi_ec_transaction(first_ec, &t);
681 EXPORT_SYMBOL(ec_transaction);
683 /* Get the handle to the EC device */
684 acpi_handle ec_get_handle(void)
688 return first_ec->handle;
690 EXPORT_SYMBOL(ec_get_handle);
693 * Process _Q events that might have accumulated in the EC.
694 * Run with locked ec mutex.
696 static void acpi_ec_clear(struct acpi_ec *ec)
701 for (i = 0; i < ACPI_EC_CLEAR_MAX; i++) {
702 status = acpi_ec_query(ec, &value);
703 if (status || !value)
707 if (unlikely(i == ACPI_EC_CLEAR_MAX))
708 pr_warn("Warning: Maximum of %d stale EC events cleared\n", i);
710 pr_info("%d stale EC events cleared\n", i);
713 static void acpi_ec_start(struct acpi_ec *ec, bool resuming)
717 spin_lock_irqsave(&ec->lock, flags);
718 if (!test_and_set_bit(EC_FLAGS_STARTED, &ec->flags)) {
719 ec_dbg_drv("Starting EC");
720 /* Enable GPE for event processing (SCI_EVT=1) */
722 acpi_ec_submit_request(ec);
723 ec_log_drv("EC started");
725 spin_unlock_irqrestore(&ec->lock, flags);
728 static bool acpi_ec_stopped(struct acpi_ec *ec)
733 spin_lock_irqsave(&ec->lock, flags);
734 flushed = acpi_ec_flushed(ec);
735 spin_unlock_irqrestore(&ec->lock, flags);
739 static void acpi_ec_stop(struct acpi_ec *ec, bool suspending)
743 spin_lock_irqsave(&ec->lock, flags);
744 if (acpi_ec_started(ec)) {
745 ec_dbg_drv("Stopping EC");
746 set_bit(EC_FLAGS_STOPPED, &ec->flags);
747 spin_unlock_irqrestore(&ec->lock, flags);
748 wait_event(ec->wait, acpi_ec_stopped(ec));
749 spin_lock_irqsave(&ec->lock, flags);
750 /* Disable GPE for event processing (SCI_EVT=1) */
752 acpi_ec_complete_request(ec);
753 clear_bit(EC_FLAGS_STARTED, &ec->flags);
754 clear_bit(EC_FLAGS_STOPPED, &ec->flags);
755 ec_log_drv("EC stopped");
757 spin_unlock_irqrestore(&ec->lock, flags);
760 void acpi_ec_block_transactions(void)
762 struct acpi_ec *ec = first_ec;
767 mutex_lock(&ec->mutex);
768 /* Prevent transactions from being carried out */
769 acpi_ec_stop(ec, true);
770 mutex_unlock(&ec->mutex);
773 void acpi_ec_unblock_transactions(void)
775 struct acpi_ec *ec = first_ec;
780 /* Allow transactions to be carried out again */
781 acpi_ec_start(ec, true);
783 if (EC_FLAGS_CLEAR_ON_RESUME)
787 void acpi_ec_unblock_transactions_early(void)
790 * Allow transactions to happen again (this function is called from
791 * atomic context during wakeup, so we don't need to acquire the mutex).
794 acpi_ec_start(first_ec, true);
797 /* --------------------------------------------------------------------------
799 -------------------------------------------------------------------------- */
800 static struct acpi_ec_query_handler *
801 acpi_ec_get_query_handler(struct acpi_ec_query_handler *handler)
804 kref_get(&handler->kref);
808 static void acpi_ec_query_handler_release(struct kref *kref)
810 struct acpi_ec_query_handler *handler =
811 container_of(kref, struct acpi_ec_query_handler, kref);
816 static void acpi_ec_put_query_handler(struct acpi_ec_query_handler *handler)
818 kref_put(&handler->kref, acpi_ec_query_handler_release);
821 int acpi_ec_add_query_handler(struct acpi_ec *ec, u8 query_bit,
822 acpi_handle handle, acpi_ec_query_func func,
825 struct acpi_ec_query_handler *handler =
826 kzalloc(sizeof(struct acpi_ec_query_handler), GFP_KERNEL);
831 handler->query_bit = query_bit;
832 handler->handle = handle;
833 handler->func = func;
834 handler->data = data;
835 mutex_lock(&ec->mutex);
836 kref_init(&handler->kref);
837 list_add(&handler->node, &ec->list);
838 mutex_unlock(&ec->mutex);
841 EXPORT_SYMBOL_GPL(acpi_ec_add_query_handler);
843 void acpi_ec_remove_query_handler(struct acpi_ec *ec, u8 query_bit)
845 struct acpi_ec_query_handler *handler, *tmp;
846 LIST_HEAD(free_list);
848 mutex_lock(&ec->mutex);
849 list_for_each_entry_safe(handler, tmp, &ec->list, node) {
850 if (query_bit == handler->query_bit) {
851 list_del_init(&handler->node);
852 list_add(&handler->node, &free_list);
855 mutex_unlock(&ec->mutex);
856 list_for_each_entry(handler, &free_list, node)
857 acpi_ec_put_query_handler(handler);
859 EXPORT_SYMBOL_GPL(acpi_ec_remove_query_handler);
861 static void acpi_ec_run(void *cxt)
863 struct acpi_ec_query_handler *handler = cxt;
867 ec_dbg_evt("Query(0x%02x) started", handler->query_bit);
869 handler->func(handler->data);
870 else if (handler->handle)
871 acpi_evaluate_object(handler->handle, NULL, NULL, NULL);
872 ec_dbg_evt("Query(0x%02x) stopped", handler->query_bit);
873 acpi_ec_put_query_handler(handler);
876 static int acpi_ec_query(struct acpi_ec *ec, u8 *data)
881 struct acpi_ec_query_handler *handler;
882 struct transaction t = {.command = ACPI_EC_COMMAND_QUERY,
883 .wdata = NULL, .rdata = &value,
884 .wlen = 0, .rlen = 1};
887 * Query the EC to find out which _Qxx method we need to evaluate.
888 * Note that successful completion of the query causes the ACPI_EC_SCI
889 * bit to be cleared (and thus clearing the interrupt source).
891 result = acpi_ec_transaction(ec, &t);
899 mutex_lock(&ec->mutex);
900 list_for_each_entry(handler, &ec->list, node) {
901 if (value == handler->query_bit) {
902 /* have custom handler for this bit */
903 handler = acpi_ec_get_query_handler(handler);
904 ec_dbg_evt("Query(0x%02x) scheduled",
906 status = acpi_os_execute((handler->func) ?
907 OSL_NOTIFY_HANDLER : OSL_GPE_HANDLER,
908 acpi_ec_run, handler);
909 if (ACPI_FAILURE(status))
914 mutex_unlock(&ec->mutex);
918 static void acpi_ec_gpe_poller(struct work_struct *work)
920 struct acpi_ec *ec = container_of(work, struct acpi_ec, work);
922 acpi_ec_query(ec, NULL);
925 static u32 acpi_ec_gpe_handler(acpi_handle gpe_device,
926 u32 gpe_number, void *data)
929 struct acpi_ec *ec = data;
931 spin_lock_irqsave(&ec->lock, flags);
932 advance_transaction(ec);
933 spin_unlock_irqrestore(&ec->lock, flags);
934 return ACPI_INTERRUPT_HANDLED;
937 /* --------------------------------------------------------------------------
938 * Address Space Management
939 * -------------------------------------------------------------------------- */
942 acpi_ec_space_handler(u32 function, acpi_physical_address address,
943 u32 bits, u64 *value64,
944 void *handler_context, void *region_context)
946 struct acpi_ec *ec = handler_context;
947 int result = 0, i, bytes = bits / 8;
948 u8 *value = (u8 *)value64;
950 if ((address > 0xFF) || !value || !handler_context)
951 return AE_BAD_PARAMETER;
953 if (function != ACPI_READ && function != ACPI_WRITE)
954 return AE_BAD_PARAMETER;
956 if (EC_FLAGS_MSI || bits > 8)
957 acpi_ec_burst_enable(ec);
959 for (i = 0; i < bytes; ++i, ++address, ++value)
960 result = (function == ACPI_READ) ?
961 acpi_ec_read(ec, address, value) :
962 acpi_ec_write(ec, address, *value);
964 if (EC_FLAGS_MSI || bits > 8)
965 acpi_ec_burst_disable(ec);
969 return AE_BAD_PARAMETER;
979 /* --------------------------------------------------------------------------
981 * -------------------------------------------------------------------------- */
984 ec_parse_io_ports(struct acpi_resource *resource, void *context);
986 static struct acpi_ec *make_acpi_ec(void)
988 struct acpi_ec *ec = kzalloc(sizeof(struct acpi_ec), GFP_KERNEL);
992 ec->flags = 1 << EC_FLAGS_QUERY_PENDING;
993 mutex_init(&ec->mutex);
994 init_waitqueue_head(&ec->wait);
995 INIT_LIST_HEAD(&ec->list);
996 spin_lock_init(&ec->lock);
997 INIT_WORK(&ec->work, acpi_ec_gpe_poller);
1002 acpi_ec_register_query_methods(acpi_handle handle, u32 level,
1003 void *context, void **return_value)
1006 struct acpi_buffer buffer = { sizeof(node_name), node_name };
1007 struct acpi_ec *ec = context;
1011 status = acpi_get_name(handle, ACPI_SINGLE_NAME, &buffer);
1013 if (ACPI_SUCCESS(status) && sscanf(node_name, "_Q%x", &value) == 1)
1014 acpi_ec_add_query_handler(ec, value, handle, NULL, NULL);
1019 ec_parse_device(acpi_handle handle, u32 Level, void *context, void **retval)
1022 unsigned long long tmp = 0;
1023 struct acpi_ec *ec = context;
1025 /* clear addr values, ec_parse_io_ports depend on it */
1026 ec->command_addr = ec->data_addr = 0;
1028 status = acpi_walk_resources(handle, METHOD_NAME__CRS,
1029 ec_parse_io_ports, ec);
1030 if (ACPI_FAILURE(status))
1033 /* Get GPE bit assignment (EC events). */
1034 /* TODO: Add support for _GPE returning a package */
1035 status = acpi_evaluate_integer(handle, "_GPE", NULL, &tmp);
1036 if (ACPI_FAILURE(status))
1039 /* Use the global lock for all EC transactions? */
1041 acpi_evaluate_integer(handle, "_GLK", NULL, &tmp);
1042 ec->global_lock = tmp;
1043 ec->handle = handle;
1044 return AE_CTRL_TERMINATE;
1047 static int ec_install_handlers(struct acpi_ec *ec)
1051 if (test_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags))
1053 status = acpi_install_gpe_raw_handler(NULL, ec->gpe,
1054 ACPI_GPE_EDGE_TRIGGERED,
1055 &acpi_ec_gpe_handler, ec);
1056 if (ACPI_FAILURE(status))
1059 acpi_ec_start(ec, false);
1060 status = acpi_install_address_space_handler(ec->handle,
1062 &acpi_ec_space_handler,
1064 if (ACPI_FAILURE(status)) {
1065 if (status == AE_NOT_FOUND) {
1067 * Maybe OS fails in evaluating the _REG object.
1068 * The AE_NOT_FOUND error will be ignored and OS
1069 * continue to initialize EC.
1071 pr_err("Fail in evaluating the _REG object"
1072 " of EC device. Broken bios is suspected.\n");
1074 acpi_ec_stop(ec, false);
1075 acpi_remove_gpe_handler(NULL, ec->gpe,
1076 &acpi_ec_gpe_handler);
1081 set_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags);
1085 static void ec_remove_handlers(struct acpi_ec *ec)
1087 if (!test_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags))
1089 acpi_ec_stop(ec, false);
1090 if (ACPI_FAILURE(acpi_remove_address_space_handler(ec->handle,
1091 ACPI_ADR_SPACE_EC, &acpi_ec_space_handler)))
1092 pr_err("failed to remove space handler\n");
1093 if (ACPI_FAILURE(acpi_remove_gpe_handler(NULL, ec->gpe,
1094 &acpi_ec_gpe_handler)))
1095 pr_err("failed to remove gpe handler\n");
1096 clear_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags);
1099 static int acpi_ec_add(struct acpi_device *device)
1101 struct acpi_ec *ec = NULL;
1104 strcpy(acpi_device_name(device), ACPI_EC_DEVICE_NAME);
1105 strcpy(acpi_device_class(device), ACPI_EC_CLASS);
1107 /* Check for boot EC */
1109 (boot_ec->handle == device->handle ||
1110 boot_ec->handle == ACPI_ROOT_OBJECT)) {
1114 ec = make_acpi_ec();
1118 if (ec_parse_device(device->handle, 0, ec, NULL) !=
1119 AE_CTRL_TERMINATE) {
1124 /* Find and register all query methods */
1125 acpi_walk_namespace(ACPI_TYPE_METHOD, ec->handle, 1,
1126 acpi_ec_register_query_methods, NULL, ec, NULL);
1130 device->driver_data = ec;
1132 ret = !!request_region(ec->data_addr, 1, "EC data");
1133 WARN(!ret, "Could not request EC data io port 0x%lx", ec->data_addr);
1134 ret = !!request_region(ec->command_addr, 1, "EC cmd");
1135 WARN(!ret, "Could not request EC cmd io port 0x%lx", ec->command_addr);
1137 pr_info("GPE = 0x%lx, I/O: command/status = 0x%lx, data = 0x%lx\n",
1138 ec->gpe, ec->command_addr, ec->data_addr);
1140 ret = ec_install_handlers(ec);
1142 /* EC is fully operational, allow queries */
1143 clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags);
1145 /* Clear stale _Q events if hardware might require that */
1146 if (EC_FLAGS_CLEAR_ON_RESUME)
1151 static int acpi_ec_remove(struct acpi_device *device)
1154 struct acpi_ec_query_handler *handler, *tmp;
1159 ec = acpi_driver_data(device);
1160 ec_remove_handlers(ec);
1161 mutex_lock(&ec->mutex);
1162 list_for_each_entry_safe(handler, tmp, &ec->list, node) {
1163 list_del(&handler->node);
1166 mutex_unlock(&ec->mutex);
1167 release_region(ec->data_addr, 1);
1168 release_region(ec->command_addr, 1);
1169 device->driver_data = NULL;
1177 ec_parse_io_ports(struct acpi_resource *resource, void *context)
1179 struct acpi_ec *ec = context;
1181 if (resource->type != ACPI_RESOURCE_TYPE_IO)
1185 * The first address region returned is the data port, and
1186 * the second address region returned is the status/command
1189 if (ec->data_addr == 0)
1190 ec->data_addr = resource->data.io.minimum;
1191 else if (ec->command_addr == 0)
1192 ec->command_addr = resource->data.io.minimum;
1194 return AE_CTRL_TERMINATE;
1199 int __init acpi_boot_ec_enable(void)
1201 if (!boot_ec || test_bit(EC_FLAGS_HANDLERS_INSTALLED, &boot_ec->flags))
1203 if (!ec_install_handlers(boot_ec)) {
1210 static const struct acpi_device_id ec_device_ids[] = {
1215 /* Some BIOS do not survive early DSDT scan, skip it */
1216 static int ec_skip_dsdt_scan(const struct dmi_system_id *id)
1218 EC_FLAGS_SKIP_DSDT_SCAN = 1;
1222 /* ASUStek often supplies us with broken ECDT, validate it */
1223 static int ec_validate_ecdt(const struct dmi_system_id *id)
1225 EC_FLAGS_VALIDATE_ECDT = 1;
1229 /* MSI EC needs special treatment, enable it */
1230 static int ec_flag_msi(const struct dmi_system_id *id)
1232 pr_debug("Detected MSI hardware, enabling workarounds.\n");
1234 EC_FLAGS_VALIDATE_ECDT = 1;
1239 * Clevo M720 notebook actually works ok with IRQ mode, if we lifted
1240 * the GPE storm threshold back to 20
1242 static int ec_enlarge_storm_threshold(const struct dmi_system_id *id)
1244 pr_debug("Setting the EC GPE storm threshold to 20\n");
1245 ec_storm_threshold = 20;
1250 * Acer EC firmware refuses to respond QR_EC when SCI_EVT is not set, for
1251 * which case, we complete the QR_EC without issuing it to the firmware.
1252 * https://bugzilla.kernel.org/show_bug.cgi?id=86211
1254 static int ec_flag_query_handshake(const struct dmi_system_id *id)
1256 pr_debug("Detected the EC firmware requiring QR_EC issued when SCI_EVT set\n");
1257 EC_FLAGS_QUERY_HANDSHAKE = 1;
1262 * On some hardware it is necessary to clear events accumulated by the EC during
1263 * sleep. These ECs stop reporting GPEs until they are manually polled, if too
1264 * many events are accumulated. (e.g. Samsung Series 5/9 notebooks)
1266 * https://bugzilla.kernel.org/show_bug.cgi?id=44161
1268 * Ideally, the EC should also be instructed NOT to accumulate events during
1269 * sleep (which Windows seems to do somehow), but the interface to control this
1270 * behaviour is not known at this time.
1272 * Models known to be affected are Samsung 530Uxx/535Uxx/540Uxx/550Pxx/900Xxx,
1273 * however it is very likely that other Samsung models are affected.
1275 * On systems which don't accumulate _Q events during sleep, this extra check
1276 * should be harmless.
1278 static int ec_clear_on_resume(const struct dmi_system_id *id)
1280 pr_debug("Detected system needing EC poll on resume.\n");
1281 EC_FLAGS_CLEAR_ON_RESUME = 1;
1285 static struct dmi_system_id ec_dmi_table[] __initdata = {
1287 ec_skip_dsdt_scan, "Compal JFL92", {
1288 DMI_MATCH(DMI_BIOS_VENDOR, "COMPAL"),
1289 DMI_MATCH(DMI_BOARD_NAME, "JFL92") }, NULL},
1291 ec_flag_msi, "MSI hardware", {
1292 DMI_MATCH(DMI_BIOS_VENDOR, "Micro-Star")}, NULL},
1294 ec_flag_msi, "MSI hardware", {
1295 DMI_MATCH(DMI_SYS_VENDOR, "Micro-Star")}, NULL},
1297 ec_flag_msi, "MSI hardware", {
1298 DMI_MATCH(DMI_CHASSIS_VENDOR, "MICRO-Star")}, NULL},
1300 ec_flag_msi, "MSI hardware", {
1301 DMI_MATCH(DMI_CHASSIS_VENDOR, "MICRO-STAR")}, NULL},
1303 ec_flag_msi, "Quanta hardware", {
1304 DMI_MATCH(DMI_SYS_VENDOR, "Quanta"),
1305 DMI_MATCH(DMI_PRODUCT_NAME, "TW8/SW8/DW8"),}, NULL},
1307 ec_flag_msi, "Quanta hardware", {
1308 DMI_MATCH(DMI_SYS_VENDOR, "Quanta"),
1309 DMI_MATCH(DMI_PRODUCT_NAME, "TW9/SW9"),}, NULL},
1311 ec_flag_msi, "Clevo W350etq", {
1312 DMI_MATCH(DMI_SYS_VENDOR, "CLEVO CO."),
1313 DMI_MATCH(DMI_PRODUCT_NAME, "W35_37ET"),}, NULL},
1315 ec_validate_ecdt, "ASUS hardware", {
1316 DMI_MATCH(DMI_BIOS_VENDOR, "ASUS") }, NULL},
1318 ec_validate_ecdt, "ASUS hardware", {
1319 DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTeK Computer Inc.") }, NULL},
1321 ec_enlarge_storm_threshold, "CLEVO hardware", {
1322 DMI_MATCH(DMI_SYS_VENDOR, "CLEVO Co."),
1323 DMI_MATCH(DMI_PRODUCT_NAME, "M720T/M730T"),}, NULL},
1325 ec_skip_dsdt_scan, "HP Folio 13", {
1326 DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
1327 DMI_MATCH(DMI_PRODUCT_NAME, "HP Folio 13"),}, NULL},
1329 ec_validate_ecdt, "ASUS hardware", {
1330 DMI_MATCH(DMI_SYS_VENDOR, "ASUSTek Computer Inc."),
1331 DMI_MATCH(DMI_PRODUCT_NAME, "L4R"),}, NULL},
1333 ec_clear_on_resume, "Samsung hardware", {
1334 DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD.")}, NULL},
1336 ec_flag_query_handshake, "Acer hardware", {
1337 DMI_MATCH(DMI_SYS_VENDOR, "Acer"), }, NULL},
1341 int __init acpi_ec_ecdt_probe(void)
1344 struct acpi_ec *saved_ec = NULL;
1345 struct acpi_table_ecdt *ecdt_ptr;
1347 boot_ec = make_acpi_ec();
1351 * Generate a boot ec context
1353 dmi_check_system(ec_dmi_table);
1354 status = acpi_get_table(ACPI_SIG_ECDT, 1,
1355 (struct acpi_table_header **)&ecdt_ptr);
1356 if (ACPI_SUCCESS(status)) {
1357 pr_info("EC description table is found, configuring boot EC\n");
1358 boot_ec->command_addr = ecdt_ptr->control.address;
1359 boot_ec->data_addr = ecdt_ptr->data.address;
1360 boot_ec->gpe = ecdt_ptr->gpe;
1361 boot_ec->handle = ACPI_ROOT_OBJECT;
1362 acpi_get_handle(ACPI_ROOT_OBJECT, ecdt_ptr->id,
1364 /* Don't trust ECDT, which comes from ASUSTek */
1365 if (!EC_FLAGS_VALIDATE_ECDT)
1367 saved_ec = kmemdup(boot_ec, sizeof(struct acpi_ec), GFP_KERNEL);
1373 if (EC_FLAGS_SKIP_DSDT_SCAN) {
1378 /* This workaround is needed only on some broken machines,
1379 * which require early EC, but fail to provide ECDT */
1380 pr_debug("Look up EC in DSDT\n");
1381 status = acpi_get_devices(ec_device_ids[0].id, ec_parse_device,
1383 /* Check that acpi_get_devices actually find something */
1384 if (ACPI_FAILURE(status) || !boot_ec->handle)
1387 /* try to find good ECDT from ASUSTek */
1388 if (saved_ec->command_addr != boot_ec->command_addr ||
1389 saved_ec->data_addr != boot_ec->data_addr ||
1390 saved_ec->gpe != boot_ec->gpe ||
1391 saved_ec->handle != boot_ec->handle)
1392 pr_info("ASUSTek keeps feeding us with broken "
1393 "ECDT tables, which are very hard to workaround. "
1394 "Trying to use DSDT EC info instead. Please send "
1395 "output of acpidump to linux-acpi@vger.kernel.org\n");
1399 /* We really need to limit this workaround, the only ASUS,
1400 * which needs it, has fake EC._INI method, so use it as flag.
1401 * Keep boot_ec struct as it will be needed soon.
1403 if (!dmi_name_in_vendors("ASUS") ||
1404 !acpi_has_method(boot_ec->handle, "_INI"))
1408 if (!ec_install_handlers(boot_ec)) {
1419 static struct acpi_driver acpi_ec_driver = {
1421 .class = ACPI_EC_CLASS,
1422 .ids = ec_device_ids,
1425 .remove = acpi_ec_remove,
1429 int __init acpi_ec_init(void)
1433 /* Now register the driver for the EC */
1434 result = acpi_bus_register_driver(&acpi_ec_driver);
1441 /* EC driver currently not unloadable */
1443 static void __exit acpi_ec_exit(void)
1446 acpi_bus_unregister_driver(&acpi_ec_driver);