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  • only in /asuswrt-rt-n18u-9.0.0.4.380.2695/release/src-rt-6.x.4708/linux/linux-2.6/drivers/acpi/
1/*
2 *  ec.c - ACPI Embedded Controller Driver (v2.1)
3 *
4 *  Copyright (C) 2006-2008 Alexey Starikovskiy <astarikovskiy@suse.de>
5 *  Copyright (C) 2006 Denis Sadykov <denis.m.sadykov@intel.com>
6 *  Copyright (C) 2004 Luming Yu <luming.yu@intel.com>
7 *  Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
8 *  Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
9 *
10 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
11 *
12 *  This program is free software; you can redistribute it and/or modify
13 *  it under the terms of the GNU General Public License as published by
14 *  the Free Software Foundation; either version 2 of the License, or (at
15 *  your option) any later version.
16 *
17 *  This program is distributed in the hope that it will be useful, but
18 *  WITHOUT ANY WARRANTY; without even the implied warranty of
19 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
20 *  General Public License for more details.
21 *
22 *  You should have received a copy of the GNU General Public License along
23 *  with this program; if not, write to the Free Software Foundation, Inc.,
24 *  59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
25 *
26 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
27 */
28
29/* Uncomment next line to get verbose printout */
30/* #define DEBUG */
31
32#include <linux/kernel.h>
33#include <linux/module.h>
34#include <linux/init.h>
35#include <linux/types.h>
36#include <linux/delay.h>
37#include <linux/interrupt.h>
38#include <linux/list.h>
39#include <linux/spinlock.h>
40#include <linux/slab.h>
41#include <asm/io.h>
42#include <acpi/acpi_bus.h>
43#include <acpi/acpi_drivers.h>
44#include <linux/dmi.h>
45
46#include "internal.h"
47
48#define ACPI_EC_CLASS			"embedded_controller"
49#define ACPI_EC_DEVICE_NAME		"Embedded Controller"
50#define ACPI_EC_FILE_INFO		"info"
51
52#undef PREFIX
53#define PREFIX				"ACPI: EC: "
54
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_BURST	0x10	/* burst mode */
59#define ACPI_EC_FLAG_SCI	0x20	/* EC-SCI occurred */
60
61/* EC commands */
62enum ec_command {
63	ACPI_EC_COMMAND_READ = 0x80,
64	ACPI_EC_COMMAND_WRITE = 0x81,
65	ACPI_EC_BURST_ENABLE = 0x82,
66	ACPI_EC_BURST_DISABLE = 0x83,
67	ACPI_EC_COMMAND_QUERY = 0x84,
68};
69
70#define ACPI_EC_DELAY		500	/* Wait 500ms max. during EC ops */
71#define ACPI_EC_UDELAY_GLK	1000	/* Wait 1ms max. to get global lock */
72#define ACPI_EC_CDELAY		10	/* Wait 10us before polling EC */
73#define ACPI_EC_MSI_UDELAY	550	/* Wait 550us for MSI EC */
74
75#define ACPI_EC_STORM_THRESHOLD 8	/* number of false interrupts
76					   per one transaction */
77
78enum {
79	EC_FLAGS_QUERY_PENDING,		/* Query is pending */
80	EC_FLAGS_GPE_STORM,		/* GPE storm detected */
81	EC_FLAGS_HANDLERS_INSTALLED,	/* Handlers for GPE and
82					 * OpReg are installed */
83	EC_FLAGS_BLOCKED,		/* Transactions are blocked */
84};
85
86/* If we find an EC via the ECDT, we need to keep a ptr to its context */
87/* External interfaces use first EC only, so remember */
88typedef int (*acpi_ec_query_func) (void *data);
89
90struct acpi_ec_query_handler {
91	struct list_head node;
92	acpi_ec_query_func func;
93	acpi_handle handle;
94	void *data;
95	u8 query_bit;
96};
97
98struct transaction {
99	const u8 *wdata;
100	u8 *rdata;
101	unsigned short irq_count;
102	u8 command;
103	u8 wi;
104	u8 ri;
105	u8 wlen;
106	u8 rlen;
107	bool done;
108};
109
110struct acpi_ec *boot_ec, *first_ec;
111EXPORT_SYMBOL(first_ec);
112
113static int EC_FLAGS_MSI; /* Out-of-spec MSI controller */
114static int EC_FLAGS_VALIDATE_ECDT; /* ASUStec ECDTs need to be validated */
115static int EC_FLAGS_SKIP_DSDT_SCAN; /* Not all BIOS survive early DSDT scan */
116
117/* --------------------------------------------------------------------------
118                             Transaction Management
119   -------------------------------------------------------------------------- */
120
121static inline u8 acpi_ec_read_status(struct acpi_ec *ec)
122{
123	u8 x = inb(ec->command_addr);
124	pr_debug(PREFIX "---> status = 0x%2.2x\n", x);
125	return x;
126}
127
128static inline u8 acpi_ec_read_data(struct acpi_ec *ec)
129{
130	u8 x = inb(ec->data_addr);
131	pr_debug(PREFIX "---> data = 0x%2.2x\n", x);
132	return x;
133}
134
135static inline void acpi_ec_write_cmd(struct acpi_ec *ec, u8 command)
136{
137	pr_debug(PREFIX "<--- command = 0x%2.2x\n", command);
138	outb(command, ec->command_addr);
139}
140
141static inline void acpi_ec_write_data(struct acpi_ec *ec, u8 data)
142{
143	pr_debug(PREFIX "<--- data = 0x%2.2x\n", data);
144	outb(data, ec->data_addr);
145}
146
147static int ec_transaction_done(struct acpi_ec *ec)
148{
149	unsigned long flags;
150	int ret = 0;
151	spin_lock_irqsave(&ec->curr_lock, flags);
152	if (!ec->curr || ec->curr->done)
153		ret = 1;
154	spin_unlock_irqrestore(&ec->curr_lock, flags);
155	return ret;
156}
157
158static void start_transaction(struct acpi_ec *ec)
159{
160	ec->curr->irq_count = ec->curr->wi = ec->curr->ri = 0;
161	ec->curr->done = false;
162	acpi_ec_write_cmd(ec, ec->curr->command);
163}
164
165static void advance_transaction(struct acpi_ec *ec, u8 status)
166{
167	unsigned long flags;
168	spin_lock_irqsave(&ec->curr_lock, flags);
169	if (!ec->curr)
170		goto unlock;
171	if (ec->curr->wlen > ec->curr->wi) {
172		if ((status & ACPI_EC_FLAG_IBF) == 0)
173			acpi_ec_write_data(ec,
174				ec->curr->wdata[ec->curr->wi++]);
175		else
176			goto err;
177	} else if (ec->curr->rlen > ec->curr->ri) {
178		if ((status & ACPI_EC_FLAG_OBF) == 1) {
179			ec->curr->rdata[ec->curr->ri++] = acpi_ec_read_data(ec);
180			if (ec->curr->rlen == ec->curr->ri)
181				ec->curr->done = true;
182		} else
183			goto err;
184	} else if (ec->curr->wlen == ec->curr->wi &&
185		   (status & ACPI_EC_FLAG_IBF) == 0)
186		ec->curr->done = true;
187	goto unlock;
188err:
189	/* false interrupt, state didn't change */
190	if (in_interrupt())
191		++ec->curr->irq_count;
192unlock:
193	spin_unlock_irqrestore(&ec->curr_lock, flags);
194}
195
196static int acpi_ec_sync_query(struct acpi_ec *ec);
197
198static int ec_check_sci_sync(struct acpi_ec *ec, u8 state)
199{
200	if (state & ACPI_EC_FLAG_SCI) {
201		if (!test_and_set_bit(EC_FLAGS_QUERY_PENDING, &ec->flags))
202			return acpi_ec_sync_query(ec);
203	}
204	return 0;
205}
206
207static int ec_poll(struct acpi_ec *ec)
208{
209	unsigned long flags;
210	int repeat = 2; /* number of command restarts */
211	while (repeat--) {
212		unsigned long delay = jiffies +
213			msecs_to_jiffies(ACPI_EC_DELAY);
214		do {
215			/* don't sleep with disabled interrupts */
216			if (EC_FLAGS_MSI || irqs_disabled()) {
217				udelay(ACPI_EC_MSI_UDELAY);
218				if (ec_transaction_done(ec))
219					return 0;
220			} else {
221				if (wait_event_timeout(ec->wait,
222						ec_transaction_done(ec),
223						msecs_to_jiffies(1)))
224					return 0;
225			}
226			advance_transaction(ec, acpi_ec_read_status(ec));
227		} while (time_before(jiffies, delay));
228		if (acpi_ec_read_status(ec) & ACPI_EC_FLAG_IBF)
229			break;
230		pr_debug(PREFIX "controller reset, restart transaction\n");
231		spin_lock_irqsave(&ec->curr_lock, flags);
232		start_transaction(ec);
233		spin_unlock_irqrestore(&ec->curr_lock, flags);
234	}
235	return -ETIME;
236}
237
238static int acpi_ec_transaction_unlocked(struct acpi_ec *ec,
239					struct transaction *t)
240{
241	unsigned long tmp;
242	int ret = 0;
243	if (EC_FLAGS_MSI)
244		udelay(ACPI_EC_MSI_UDELAY);
245	/* start transaction */
246	spin_lock_irqsave(&ec->curr_lock, tmp);
247	/* following two actions should be kept atomic */
248	ec->curr = t;
249	start_transaction(ec);
250	if (ec->curr->command == ACPI_EC_COMMAND_QUERY)
251		clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags);
252	spin_unlock_irqrestore(&ec->curr_lock, tmp);
253	ret = ec_poll(ec);
254	spin_lock_irqsave(&ec->curr_lock, tmp);
255	ec->curr = NULL;
256	spin_unlock_irqrestore(&ec->curr_lock, tmp);
257	return ret;
258}
259
260static int ec_check_ibf0(struct acpi_ec *ec)
261{
262	u8 status = acpi_ec_read_status(ec);
263	return (status & ACPI_EC_FLAG_IBF) == 0;
264}
265
266static int ec_wait_ibf0(struct acpi_ec *ec)
267{
268	unsigned long delay = jiffies + msecs_to_jiffies(ACPI_EC_DELAY);
269	/* interrupt wait manually if GPE mode is not active */
270	while (time_before(jiffies, delay))
271		if (wait_event_timeout(ec->wait, ec_check_ibf0(ec),
272					msecs_to_jiffies(1)))
273			return 0;
274	return -ETIME;
275}
276
277static int acpi_ec_transaction(struct acpi_ec *ec, struct transaction *t)
278{
279	int status;
280	u32 glk;
281	if (!ec || (!t) || (t->wlen && !t->wdata) || (t->rlen && !t->rdata))
282		return -EINVAL;
283	if (t->rdata)
284		memset(t->rdata, 0, t->rlen);
285	mutex_lock(&ec->lock);
286	if (test_bit(EC_FLAGS_BLOCKED, &ec->flags)) {
287		status = -EINVAL;
288		goto unlock;
289	}
290	if (ec->global_lock) {
291		status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk);
292		if (ACPI_FAILURE(status)) {
293			status = -ENODEV;
294			goto unlock;
295		}
296	}
297	if (ec_wait_ibf0(ec)) {
298		pr_err(PREFIX "input buffer is not empty, "
299				"aborting transaction\n");
300		status = -ETIME;
301		goto end;
302	}
303	pr_debug(PREFIX "transaction start\n");
304	/* disable GPE during transaction if storm is detected */
305	if (test_bit(EC_FLAGS_GPE_STORM, &ec->flags)) {
306		/* It has to be disabled, so that it doesn't trigger. */
307		acpi_disable_gpe(NULL, ec->gpe);
308	}
309
310	status = acpi_ec_transaction_unlocked(ec, t);
311
312	/* check if we received SCI during transaction */
313	ec_check_sci_sync(ec, acpi_ec_read_status(ec));
314	if (test_bit(EC_FLAGS_GPE_STORM, &ec->flags)) {
315		msleep(1);
316		/* It is safe to enable the GPE outside of the transaction. */
317		acpi_enable_gpe(NULL, ec->gpe);
318	} else if (t->irq_count > ACPI_EC_STORM_THRESHOLD) {
319		pr_info(PREFIX "GPE storm detected, "
320			"transactions will use polling mode\n");
321		set_bit(EC_FLAGS_GPE_STORM, &ec->flags);
322	}
323	pr_debug(PREFIX "transaction end\n");
324end:
325	if (ec->global_lock)
326		acpi_release_global_lock(glk);
327unlock:
328	mutex_unlock(&ec->lock);
329	return status;
330}
331
332static int acpi_ec_burst_enable(struct acpi_ec *ec)
333{
334	u8 d;
335	struct transaction t = {.command = ACPI_EC_BURST_ENABLE,
336				.wdata = NULL, .rdata = &d,
337				.wlen = 0, .rlen = 1};
338
339	return acpi_ec_transaction(ec, &t);
340}
341
342static int acpi_ec_burst_disable(struct acpi_ec *ec)
343{
344	struct transaction t = {.command = ACPI_EC_BURST_DISABLE,
345				.wdata = NULL, .rdata = NULL,
346				.wlen = 0, .rlen = 0};
347
348	return (acpi_ec_read_status(ec) & ACPI_EC_FLAG_BURST) ?
349				acpi_ec_transaction(ec, &t) : 0;
350}
351
352static int acpi_ec_read(struct acpi_ec *ec, u8 address, u8 * data)
353{
354	int result;
355	u8 d;
356	struct transaction t = {.command = ACPI_EC_COMMAND_READ,
357				.wdata = &address, .rdata = &d,
358				.wlen = 1, .rlen = 1};
359
360	result = acpi_ec_transaction(ec, &t);
361	*data = d;
362	return result;
363}
364
365static int acpi_ec_write(struct acpi_ec *ec, u8 address, u8 data)
366{
367	u8 wdata[2] = { address, data };
368	struct transaction t = {.command = ACPI_EC_COMMAND_WRITE,
369				.wdata = wdata, .rdata = NULL,
370				.wlen = 2, .rlen = 0};
371
372	return acpi_ec_transaction(ec, &t);
373}
374
375/*
376 * Externally callable EC access functions. For now, assume 1 EC only
377 */
378int ec_burst_enable(void)
379{
380	if (!first_ec)
381		return -ENODEV;
382	return acpi_ec_burst_enable(first_ec);
383}
384
385EXPORT_SYMBOL(ec_burst_enable);
386
387int ec_burst_disable(void)
388{
389	if (!first_ec)
390		return -ENODEV;
391	return acpi_ec_burst_disable(first_ec);
392}
393
394EXPORT_SYMBOL(ec_burst_disable);
395
396int ec_read(u8 addr, u8 * val)
397{
398	int err;
399	u8 temp_data;
400
401	if (!first_ec)
402		return -ENODEV;
403
404	err = acpi_ec_read(first_ec, addr, &temp_data);
405
406	if (!err) {
407		*val = temp_data;
408		return 0;
409	} else
410		return err;
411}
412
413EXPORT_SYMBOL(ec_read);
414
415int ec_write(u8 addr, u8 val)
416{
417	int err;
418
419	if (!first_ec)
420		return -ENODEV;
421
422	err = acpi_ec_write(first_ec, addr, val);
423
424	return err;
425}
426
427EXPORT_SYMBOL(ec_write);
428
429int ec_transaction(u8 command,
430		   const u8 * wdata, unsigned wdata_len,
431		   u8 * rdata, unsigned rdata_len,
432		   int force_poll)
433{
434	struct transaction t = {.command = command,
435				.wdata = wdata, .rdata = rdata,
436				.wlen = wdata_len, .rlen = rdata_len};
437	if (!first_ec)
438		return -ENODEV;
439
440	return acpi_ec_transaction(first_ec, &t);
441}
442
443EXPORT_SYMBOL(ec_transaction);
444
445void acpi_ec_block_transactions(void)
446{
447	struct acpi_ec *ec = first_ec;
448
449	if (!ec)
450		return;
451
452	mutex_lock(&ec->lock);
453	/* Prevent transactions from being carried out */
454	set_bit(EC_FLAGS_BLOCKED, &ec->flags);
455	mutex_unlock(&ec->lock);
456}
457
458void acpi_ec_unblock_transactions(void)
459{
460	struct acpi_ec *ec = first_ec;
461
462	if (!ec)
463		return;
464
465	mutex_lock(&ec->lock);
466	/* Allow transactions to be carried out again */
467	clear_bit(EC_FLAGS_BLOCKED, &ec->flags);
468	mutex_unlock(&ec->lock);
469}
470
471void acpi_ec_unblock_transactions_early(void)
472{
473	/*
474	 * Allow transactions to happen again (this function is called from
475	 * atomic context during wakeup, so we don't need to acquire the mutex).
476	 */
477	if (first_ec)
478		clear_bit(EC_FLAGS_BLOCKED, &first_ec->flags);
479}
480
481static int acpi_ec_query_unlocked(struct acpi_ec *ec, u8 * data)
482{
483	int result;
484	u8 d;
485	struct transaction t = {.command = ACPI_EC_COMMAND_QUERY,
486				.wdata = NULL, .rdata = &d,
487				.wlen = 0, .rlen = 1};
488	if (!ec || !data)
489		return -EINVAL;
490	/*
491	 * Query the EC to find out which _Qxx method we need to evaluate.
492	 * Note that successful completion of the query causes the ACPI_EC_SCI
493	 * bit to be cleared (and thus clearing the interrupt source).
494	 */
495	result = acpi_ec_transaction_unlocked(ec, &t);
496	if (result)
497		return result;
498	if (!d)
499		return -ENODATA;
500	*data = d;
501	return 0;
502}
503
504/* --------------------------------------------------------------------------
505                                Event Management
506   -------------------------------------------------------------------------- */
507int acpi_ec_add_query_handler(struct acpi_ec *ec, u8 query_bit,
508			      acpi_handle handle, acpi_ec_query_func func,
509			      void *data)
510{
511	struct acpi_ec_query_handler *handler =
512	    kzalloc(sizeof(struct acpi_ec_query_handler), GFP_KERNEL);
513	if (!handler)
514		return -ENOMEM;
515
516	handler->query_bit = query_bit;
517	handler->handle = handle;
518	handler->func = func;
519	handler->data = data;
520	mutex_lock(&ec->lock);
521	list_add(&handler->node, &ec->list);
522	mutex_unlock(&ec->lock);
523	return 0;
524}
525
526EXPORT_SYMBOL_GPL(acpi_ec_add_query_handler);
527
528void acpi_ec_remove_query_handler(struct acpi_ec *ec, u8 query_bit)
529{
530	struct acpi_ec_query_handler *handler, *tmp;
531	mutex_lock(&ec->lock);
532	list_for_each_entry_safe(handler, tmp, &ec->list, node) {
533		if (query_bit == handler->query_bit) {
534			list_del(&handler->node);
535			kfree(handler);
536		}
537	}
538	mutex_unlock(&ec->lock);
539}
540
541EXPORT_SYMBOL_GPL(acpi_ec_remove_query_handler);
542
543static void acpi_ec_run(void *cxt)
544{
545	struct acpi_ec_query_handler *handler = cxt;
546	if (!handler)
547		return;
548	pr_debug(PREFIX "start query execution\n");
549	if (handler->func)
550		handler->func(handler->data);
551	else if (handler->handle)
552		acpi_evaluate_object(handler->handle, NULL, NULL, NULL);
553	pr_debug(PREFIX "stop query execution\n");
554	kfree(handler);
555}
556
557static int acpi_ec_sync_query(struct acpi_ec *ec)
558{
559	u8 value = 0;
560	int status;
561	struct acpi_ec_query_handler *handler, *copy;
562	if ((status = acpi_ec_query_unlocked(ec, &value)))
563		return status;
564	list_for_each_entry(handler, &ec->list, node) {
565		if (value == handler->query_bit) {
566			/* have custom handler for this bit */
567			copy = kmalloc(sizeof(*handler), GFP_KERNEL);
568			if (!copy)
569				return -ENOMEM;
570			memcpy(copy, handler, sizeof(*copy));
571			pr_debug(PREFIX "push query execution (0x%2x) on queue\n", value);
572			return acpi_os_execute((copy->func) ?
573				OSL_NOTIFY_HANDLER : OSL_GPE_HANDLER,
574				acpi_ec_run, copy);
575		}
576	}
577	return 0;
578}
579
580static void acpi_ec_gpe_query(void *ec_cxt)
581{
582	struct acpi_ec *ec = ec_cxt;
583	if (!ec)
584		return;
585	mutex_lock(&ec->lock);
586	acpi_ec_sync_query(ec);
587	mutex_unlock(&ec->lock);
588}
589
590static void acpi_ec_gpe_query(void *ec_cxt);
591
592static int ec_check_sci(struct acpi_ec *ec, u8 state)
593{
594	if (state & ACPI_EC_FLAG_SCI) {
595		if (!test_and_set_bit(EC_FLAGS_QUERY_PENDING, &ec->flags)) {
596			pr_debug(PREFIX "push gpe query to the queue\n");
597			return acpi_os_execute(OSL_NOTIFY_HANDLER,
598				acpi_ec_gpe_query, ec);
599		}
600	}
601	return 0;
602}
603
604static u32 acpi_ec_gpe_handler(void *data)
605{
606	struct acpi_ec *ec = data;
607
608	pr_debug(PREFIX "~~~> interrupt\n");
609
610	advance_transaction(ec, acpi_ec_read_status(ec));
611	if (ec_transaction_done(ec) &&
612	    (acpi_ec_read_status(ec) & ACPI_EC_FLAG_IBF) == 0) {
613		wake_up(&ec->wait);
614		ec_check_sci(ec, acpi_ec_read_status(ec));
615	}
616	return ACPI_INTERRUPT_HANDLED;
617}
618
619/* --------------------------------------------------------------------------
620                             Address Space Management
621   -------------------------------------------------------------------------- */
622
623static acpi_status
624acpi_ec_space_handler(u32 function, acpi_physical_address address,
625		      u32 bits, u64 *value64,
626		      void *handler_context, void *region_context)
627{
628	struct acpi_ec *ec = handler_context;
629	int result = 0, i, bytes = bits / 8;
630	u8 *value = (u8 *)value64;
631
632	if ((address > 0xFF) || !value || !handler_context)
633		return AE_BAD_PARAMETER;
634
635	if (function != ACPI_READ && function != ACPI_WRITE)
636		return AE_BAD_PARAMETER;
637
638	if (EC_FLAGS_MSI || bits > 8)
639		acpi_ec_burst_enable(ec);
640
641	for (i = 0; i < bytes; ++i, ++address, ++value)
642		result = (function == ACPI_READ) ?
643			acpi_ec_read(ec, address, value) :
644			acpi_ec_write(ec, address, *value);
645
646	if (EC_FLAGS_MSI || bits > 8)
647		acpi_ec_burst_disable(ec);
648
649	switch (result) {
650	case -EINVAL:
651		return AE_BAD_PARAMETER;
652		break;
653	case -ENODEV:
654		return AE_NOT_FOUND;
655		break;
656	case -ETIME:
657		return AE_TIME;
658		break;
659	default:
660		return AE_OK;
661	}
662}
663
664/* --------------------------------------------------------------------------
665                               Driver Interface
666   -------------------------------------------------------------------------- */
667static acpi_status
668ec_parse_io_ports(struct acpi_resource *resource, void *context);
669
670static struct acpi_ec *make_acpi_ec(void)
671{
672	struct acpi_ec *ec = kzalloc(sizeof(struct acpi_ec), GFP_KERNEL);
673	if (!ec)
674		return NULL;
675	ec->flags = 1 << EC_FLAGS_QUERY_PENDING;
676	mutex_init(&ec->lock);
677	init_waitqueue_head(&ec->wait);
678	INIT_LIST_HEAD(&ec->list);
679	spin_lock_init(&ec->curr_lock);
680	return ec;
681}
682
683static acpi_status
684acpi_ec_register_query_methods(acpi_handle handle, u32 level,
685			       void *context, void **return_value)
686{
687	char node_name[5];
688	struct acpi_buffer buffer = { sizeof(node_name), node_name };
689	struct acpi_ec *ec = context;
690	int value = 0;
691	acpi_status status;
692
693	status = acpi_get_name(handle, ACPI_SINGLE_NAME, &buffer);
694
695	if (ACPI_SUCCESS(status) && sscanf(node_name, "_Q%x", &value) == 1) {
696		acpi_ec_add_query_handler(ec, value, handle, NULL, NULL);
697	}
698	return AE_OK;
699}
700
701static acpi_status
702ec_parse_device(acpi_handle handle, u32 Level, void *context, void **retval)
703{
704	acpi_status status;
705	unsigned long long tmp = 0;
706
707	struct acpi_ec *ec = context;
708
709	/* clear addr values, ec_parse_io_ports depend on it */
710	ec->command_addr = ec->data_addr = 0;
711
712	status = acpi_walk_resources(handle, METHOD_NAME__CRS,
713				     ec_parse_io_ports, ec);
714	if (ACPI_FAILURE(status))
715		return status;
716
717	/* Get GPE bit assignment (EC events). */
718	/* TODO: Add support for _GPE returning a package */
719	status = acpi_evaluate_integer(handle, "_GPE", NULL, &tmp);
720	if (ACPI_FAILURE(status))
721		return status;
722	ec->gpe = tmp;
723	/* Use the global lock for all EC transactions? */
724	tmp = 0;
725	acpi_evaluate_integer(handle, "_GLK", NULL, &tmp);
726	ec->global_lock = tmp;
727	ec->handle = handle;
728	return AE_CTRL_TERMINATE;
729}
730
731static int ec_install_handlers(struct acpi_ec *ec)
732{
733	acpi_status status;
734	if (test_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags))
735		return 0;
736	status = acpi_install_gpe_handler(NULL, ec->gpe,
737				  ACPI_GPE_EDGE_TRIGGERED,
738				  &acpi_ec_gpe_handler, ec);
739	if (ACPI_FAILURE(status))
740		return -ENODEV;
741
742	acpi_enable_gpe(NULL, ec->gpe);
743	status = acpi_install_address_space_handler(ec->handle,
744						    ACPI_ADR_SPACE_EC,
745						    &acpi_ec_space_handler,
746						    NULL, ec);
747	if (ACPI_FAILURE(status)) {
748		if (status == AE_NOT_FOUND) {
749			/*
750			 * Maybe OS fails in evaluating the _REG object.
751			 * The AE_NOT_FOUND error will be ignored and OS
752			 * continue to initialize EC.
753			 */
754			printk(KERN_ERR "Fail in evaluating the _REG object"
755				" of EC device. Broken bios is suspected.\n");
756		} else {
757			acpi_remove_gpe_handler(NULL, ec->gpe,
758				&acpi_ec_gpe_handler);
759			acpi_disable_gpe(NULL, ec->gpe);
760			return -ENODEV;
761		}
762	}
763
764	set_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags);
765	return 0;
766}
767
768static void ec_remove_handlers(struct acpi_ec *ec)
769{
770	acpi_disable_gpe(NULL, ec->gpe);
771	if (ACPI_FAILURE(acpi_remove_address_space_handler(ec->handle,
772				ACPI_ADR_SPACE_EC, &acpi_ec_space_handler)))
773		pr_err(PREFIX "failed to remove space handler\n");
774	if (ACPI_FAILURE(acpi_remove_gpe_handler(NULL, ec->gpe,
775				&acpi_ec_gpe_handler)))
776		pr_err(PREFIX "failed to remove gpe handler\n");
777	clear_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags);
778}
779
780static int acpi_ec_add(struct acpi_device *device)
781{
782	struct acpi_ec *ec = NULL;
783	int ret;
784
785	strcpy(acpi_device_name(device), ACPI_EC_DEVICE_NAME);
786	strcpy(acpi_device_class(device), ACPI_EC_CLASS);
787
788	/* Check for boot EC */
789	if (boot_ec &&
790	    (boot_ec->handle == device->handle ||
791	     boot_ec->handle == ACPI_ROOT_OBJECT)) {
792		ec = boot_ec;
793		boot_ec = NULL;
794	} else {
795		ec = make_acpi_ec();
796		if (!ec)
797			return -ENOMEM;
798	}
799	if (ec_parse_device(device->handle, 0, ec, NULL) !=
800		AE_CTRL_TERMINATE) {
801			kfree(ec);
802			return -EINVAL;
803	}
804
805	ec->handle = device->handle;
806
807	/* Find and register all query methods */
808	acpi_walk_namespace(ACPI_TYPE_METHOD, ec->handle, 1,
809			    acpi_ec_register_query_methods, NULL, ec, NULL);
810
811	if (!first_ec)
812		first_ec = ec;
813	device->driver_data = ec;
814
815	WARN(!request_region(ec->data_addr, 1, "EC data"),
816	     "Could not request EC data io port 0x%lx", ec->data_addr);
817	WARN(!request_region(ec->command_addr, 1, "EC cmd"),
818	     "Could not request EC cmd io port 0x%lx", ec->command_addr);
819
820	pr_info(PREFIX "GPE = 0x%lx, I/O: command/status = 0x%lx, data = 0x%lx\n",
821			  ec->gpe, ec->command_addr, ec->data_addr);
822
823	ret = ec_install_handlers(ec);
824
825	/* EC is fully operational, allow queries */
826	clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags);
827	return ret;
828}
829
830static int acpi_ec_remove(struct acpi_device *device, int type)
831{
832	struct acpi_ec *ec;
833	struct acpi_ec_query_handler *handler, *tmp;
834
835	if (!device)
836		return -EINVAL;
837
838	ec = acpi_driver_data(device);
839	ec_remove_handlers(ec);
840	mutex_lock(&ec->lock);
841	list_for_each_entry_safe(handler, tmp, &ec->list, node) {
842		list_del(&handler->node);
843		kfree(handler);
844	}
845	mutex_unlock(&ec->lock);
846	release_region(ec->data_addr, 1);
847	release_region(ec->command_addr, 1);
848	device->driver_data = NULL;
849	if (ec == first_ec)
850		first_ec = NULL;
851	kfree(ec);
852	return 0;
853}
854
855static acpi_status
856ec_parse_io_ports(struct acpi_resource *resource, void *context)
857{
858	struct acpi_ec *ec = context;
859
860	if (resource->type != ACPI_RESOURCE_TYPE_IO)
861		return AE_OK;
862
863	/*
864	 * The first address region returned is the data port, and
865	 * the second address region returned is the status/command
866	 * port.
867	 */
868	if (ec->data_addr == 0)
869		ec->data_addr = resource->data.io.minimum;
870	else if (ec->command_addr == 0)
871		ec->command_addr = resource->data.io.minimum;
872	else
873		return AE_CTRL_TERMINATE;
874
875	return AE_OK;
876}
877
878int __init acpi_boot_ec_enable(void)
879{
880	if (!boot_ec || test_bit(EC_FLAGS_HANDLERS_INSTALLED, &boot_ec->flags))
881		return 0;
882	if (!ec_install_handlers(boot_ec)) {
883		first_ec = boot_ec;
884		return 0;
885	}
886	return -EFAULT;
887}
888
889static const struct acpi_device_id ec_device_ids[] = {
890	{"PNP0C09", 0},
891	{"", 0},
892};
893
894/* Some BIOS do not survive early DSDT scan, skip it */
895static int ec_skip_dsdt_scan(const struct dmi_system_id *id)
896{
897	EC_FLAGS_SKIP_DSDT_SCAN = 1;
898	return 0;
899}
900
901/* ASUStek often supplies us with broken ECDT, validate it */
902static int ec_validate_ecdt(const struct dmi_system_id *id)
903{
904	EC_FLAGS_VALIDATE_ECDT = 1;
905	return 0;
906}
907
908/* MSI EC needs special treatment, enable it */
909static int ec_flag_msi(const struct dmi_system_id *id)
910{
911	printk(KERN_DEBUG PREFIX "Detected MSI hardware, enabling workarounds.\n");
912	EC_FLAGS_MSI = 1;
913	EC_FLAGS_VALIDATE_ECDT = 1;
914	return 0;
915}
916
917static struct dmi_system_id __initdata ec_dmi_table[] = {
918	{
919	ec_skip_dsdt_scan, "Compal JFL92", {
920	DMI_MATCH(DMI_BIOS_VENDOR, "COMPAL"),
921	DMI_MATCH(DMI_BOARD_NAME, "JFL92") }, NULL},
922	{
923	ec_flag_msi, "MSI hardware", {
924	DMI_MATCH(DMI_BIOS_VENDOR, "Micro-Star")}, NULL},
925	{
926	ec_flag_msi, "MSI hardware", {
927	DMI_MATCH(DMI_SYS_VENDOR, "Micro-Star")}, NULL},
928	{
929	ec_flag_msi, "MSI hardware", {
930	DMI_MATCH(DMI_CHASSIS_VENDOR, "MICRO-Star")}, NULL},
931	{
932	ec_flag_msi, "MSI hardware", {
933	DMI_MATCH(DMI_CHASSIS_VENDOR, "MICRO-STAR")}, NULL},
934	{
935	ec_validate_ecdt, "ASUS hardware", {
936	DMI_MATCH(DMI_BIOS_VENDOR, "ASUS") }, NULL},
937	{},
938};
939
940
941int __init acpi_ec_ecdt_probe(void)
942{
943	acpi_status status;
944	struct acpi_ec *saved_ec = NULL;
945	struct acpi_table_ecdt *ecdt_ptr;
946
947	boot_ec = make_acpi_ec();
948	if (!boot_ec)
949		return -ENOMEM;
950	/*
951	 * Generate a boot ec context
952	 */
953	dmi_check_system(ec_dmi_table);
954	status = acpi_get_table(ACPI_SIG_ECDT, 1,
955				(struct acpi_table_header **)&ecdt_ptr);
956	if (ACPI_SUCCESS(status)) {
957		pr_info(PREFIX "EC description table is found, configuring boot EC\n");
958		boot_ec->command_addr = ecdt_ptr->control.address;
959		boot_ec->data_addr = ecdt_ptr->data.address;
960		boot_ec->gpe = ecdt_ptr->gpe;
961		boot_ec->handle = ACPI_ROOT_OBJECT;
962		acpi_get_handle(ACPI_ROOT_OBJECT, ecdt_ptr->id, &boot_ec->handle);
963		/* Don't trust ECDT, which comes from ASUSTek */
964		if (!EC_FLAGS_VALIDATE_ECDT)
965			goto install;
966		saved_ec = kmemdup(boot_ec, sizeof(struct acpi_ec), GFP_KERNEL);
967		if (!saved_ec)
968			return -ENOMEM;
969	/* fall through */
970	}
971
972	if (EC_FLAGS_SKIP_DSDT_SCAN)
973		return -ENODEV;
974
975	printk(KERN_DEBUG PREFIX "Look up EC in DSDT\n");
976	status = acpi_get_devices(ec_device_ids[0].id, ec_parse_device,
977					boot_ec, NULL);
978	/* Check that acpi_get_devices actually find something */
979	if (ACPI_FAILURE(status) || !boot_ec->handle)
980		goto error;
981	if (saved_ec) {
982		/* try to find good ECDT from ASUSTek */
983		if (saved_ec->command_addr != boot_ec->command_addr ||
984		    saved_ec->data_addr != boot_ec->data_addr ||
985		    saved_ec->gpe != boot_ec->gpe ||
986		    saved_ec->handle != boot_ec->handle)
987			pr_info(PREFIX "ASUSTek keeps feeding us with broken "
988			"ECDT tables, which are very hard to workaround. "
989			"Trying to use DSDT EC info instead. Please send "
990			"output of acpidump to linux-acpi@vger.kernel.org\n");
991		kfree(saved_ec);
992		saved_ec = NULL;
993	} else {
994		acpi_handle dummy;
995		if (!dmi_name_in_vendors("ASUS") ||
996		    ACPI_FAILURE(acpi_get_handle(boot_ec->handle, "_INI",
997							&dummy)))
998			return -ENODEV;
999	}
1000install:
1001	if (!ec_install_handlers(boot_ec)) {
1002		first_ec = boot_ec;
1003		return 0;
1004	}
1005error:
1006	kfree(boot_ec);
1007	boot_ec = NULL;
1008	return -ENODEV;
1009}
1010
1011static struct acpi_driver acpi_ec_driver = {
1012	.name = "ec",
1013	.class = ACPI_EC_CLASS,
1014	.ids = ec_device_ids,
1015	.ops = {
1016		.add = acpi_ec_add,
1017		.remove = acpi_ec_remove,
1018		},
1019};
1020
1021int __init acpi_ec_init(void)
1022{
1023	int result = 0;
1024
1025	/* Now register the driver for the EC */
1026	result = acpi_bus_register_driver(&acpi_ec_driver);
1027	if (result < 0)
1028		return -ENODEV;
1029
1030	return result;
1031}
1032
1033/* EC driver currently not unloadable */
1034