Merge branch 'ec-cleanup' into release
[linux-2.6.git] / drivers / acpi / ec.c
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 */
62 enum 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_MSI_UDELAY      550     /* Wait 550us for MSI EC */
73
74 #define ACPI_EC_STORM_THRESHOLD 8       /* number of false interrupts
75                                            per one transaction */
76
77 enum {
78         EC_FLAGS_QUERY_PENDING,         /* Query is pending */
79         EC_FLAGS_GPE_STORM,             /* GPE storm detected */
80         EC_FLAGS_HANDLERS_INSTALLED,    /* Handlers for GPE and
81                                          * OpReg are installed */
82         EC_FLAGS_BLOCKED,               /* Transactions are blocked */
83 };
84
85 /* ec.c is compiled in acpi namespace so this shows up as acpi.ec_delay param */
86 static unsigned int ec_delay __read_mostly = ACPI_EC_DELAY;
87 module_param(ec_delay, uint, 0644);
88 MODULE_PARM_DESC(ec_delay, "Timeout(ms) waited until an EC command completes");
89
90 /* If we find an EC via the ECDT, we need to keep a ptr to its context */
91 /* External interfaces use first EC only, so remember */
92 typedef int (*acpi_ec_query_func) (void *data);
93
94 struct acpi_ec_query_handler {
95         struct list_head node;
96         acpi_ec_query_func func;
97         acpi_handle handle;
98         void *data;
99         u8 query_bit;
100 };
101
102 struct transaction {
103         const u8 *wdata;
104         u8 *rdata;
105         unsigned short irq_count;
106         u8 command;
107         u8 wi;
108         u8 ri;
109         u8 wlen;
110         u8 rlen;
111         bool done;
112 };
113
114 struct acpi_ec *boot_ec, *first_ec;
115 EXPORT_SYMBOL(first_ec);
116
117 static int EC_FLAGS_MSI; /* Out-of-spec MSI controller */
118 static int EC_FLAGS_VALIDATE_ECDT; /* ASUStec ECDTs need to be validated */
119 static int EC_FLAGS_SKIP_DSDT_SCAN; /* Not all BIOS survive early DSDT scan */
120
121 /* --------------------------------------------------------------------------
122                              Transaction Management
123    -------------------------------------------------------------------------- */
124
125 static inline u8 acpi_ec_read_status(struct acpi_ec *ec)
126 {
127         u8 x = inb(ec->command_addr);
128         pr_debug(PREFIX "---> status = 0x%2.2x\n", x);
129         return x;
130 }
131
132 static inline u8 acpi_ec_read_data(struct acpi_ec *ec)
133 {
134         u8 x = inb(ec->data_addr);
135         pr_debug(PREFIX "---> data = 0x%2.2x\n", x);
136         return x;
137 }
138
139 static inline void acpi_ec_write_cmd(struct acpi_ec *ec, u8 command)
140 {
141         pr_debug(PREFIX "<--- command = 0x%2.2x\n", command);
142         outb(command, ec->command_addr);
143 }
144
145 static inline void acpi_ec_write_data(struct acpi_ec *ec, u8 data)
146 {
147         pr_debug(PREFIX "<--- data = 0x%2.2x\n", data);
148         outb(data, ec->data_addr);
149 }
150
151 static int ec_transaction_done(struct acpi_ec *ec)
152 {
153         unsigned long flags;
154         int ret = 0;
155         spin_lock_irqsave(&ec->curr_lock, flags);
156         if (!ec->curr || ec->curr->done)
157                 ret = 1;
158         spin_unlock_irqrestore(&ec->curr_lock, flags);
159         return ret;
160 }
161
162 static void start_transaction(struct acpi_ec *ec)
163 {
164         ec->curr->irq_count = ec->curr->wi = ec->curr->ri = 0;
165         ec->curr->done = false;
166         acpi_ec_write_cmd(ec, ec->curr->command);
167 }
168
169 static void advance_transaction(struct acpi_ec *ec, u8 status)
170 {
171         unsigned long flags;
172         spin_lock_irqsave(&ec->curr_lock, flags);
173         if (!ec->curr)
174                 goto unlock;
175         if (ec->curr->wlen > ec->curr->wi) {
176                 if ((status & ACPI_EC_FLAG_IBF) == 0)
177                         acpi_ec_write_data(ec,
178                                 ec->curr->wdata[ec->curr->wi++]);
179                 else
180                         goto err;
181         } else if (ec->curr->rlen > ec->curr->ri) {
182                 if ((status & ACPI_EC_FLAG_OBF) == 1) {
183                         ec->curr->rdata[ec->curr->ri++] = acpi_ec_read_data(ec);
184                         if (ec->curr->rlen == ec->curr->ri)
185                                 ec->curr->done = true;
186                 } else
187                         goto err;
188         } else if (ec->curr->wlen == ec->curr->wi &&
189                    (status & ACPI_EC_FLAG_IBF) == 0)
190                 ec->curr->done = true;
191         goto unlock;
192 err:
193         /* false interrupt, state didn't change */
194         if (in_interrupt())
195                 ++ec->curr->irq_count;
196 unlock:
197         spin_unlock_irqrestore(&ec->curr_lock, flags);
198 }
199
200 static int acpi_ec_sync_query(struct acpi_ec *ec);
201
202 static int ec_check_sci_sync(struct acpi_ec *ec, u8 state)
203 {
204         if (state & ACPI_EC_FLAG_SCI) {
205                 if (!test_and_set_bit(EC_FLAGS_QUERY_PENDING, &ec->flags))
206                         return acpi_ec_sync_query(ec);
207         }
208         return 0;
209 }
210
211 static int ec_poll(struct acpi_ec *ec)
212 {
213         unsigned long flags;
214         int repeat = 2; /* number of command restarts */
215         while (repeat--) {
216                 unsigned long delay = jiffies +
217                         msecs_to_jiffies(ec_delay);
218                 do {
219                         /* don't sleep with disabled interrupts */
220                         if (EC_FLAGS_MSI || irqs_disabled()) {
221                                 udelay(ACPI_EC_MSI_UDELAY);
222                                 if (ec_transaction_done(ec))
223                                         return 0;
224                         } else {
225                                 if (wait_event_timeout(ec->wait,
226                                                 ec_transaction_done(ec),
227                                                 msecs_to_jiffies(1)))
228                                         return 0;
229                         }
230                         advance_transaction(ec, acpi_ec_read_status(ec));
231                 } while (time_before(jiffies, delay));
232                 if (acpi_ec_read_status(ec) & ACPI_EC_FLAG_IBF)
233                         break;
234                 pr_debug(PREFIX "controller reset, restart transaction\n");
235                 spin_lock_irqsave(&ec->curr_lock, flags);
236                 start_transaction(ec);
237                 spin_unlock_irqrestore(&ec->curr_lock, flags);
238         }
239         return -ETIME;
240 }
241
242 static int acpi_ec_transaction_unlocked(struct acpi_ec *ec,
243                                         struct transaction *t)
244 {
245         unsigned long tmp;
246         int ret = 0;
247         if (EC_FLAGS_MSI)
248                 udelay(ACPI_EC_MSI_UDELAY);
249         /* start transaction */
250         spin_lock_irqsave(&ec->curr_lock, tmp);
251         /* following two actions should be kept atomic */
252         ec->curr = t;
253         start_transaction(ec);
254         if (ec->curr->command == ACPI_EC_COMMAND_QUERY)
255                 clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags);
256         spin_unlock_irqrestore(&ec->curr_lock, tmp);
257         ret = ec_poll(ec);
258         spin_lock_irqsave(&ec->curr_lock, tmp);
259         ec->curr = NULL;
260         spin_unlock_irqrestore(&ec->curr_lock, tmp);
261         return ret;
262 }
263
264 static int ec_check_ibf0(struct acpi_ec *ec)
265 {
266         u8 status = acpi_ec_read_status(ec);
267         return (status & ACPI_EC_FLAG_IBF) == 0;
268 }
269
270 static int ec_wait_ibf0(struct acpi_ec *ec)
271 {
272         unsigned long delay = jiffies + msecs_to_jiffies(ec_delay);
273         /* interrupt wait manually if GPE mode is not active */
274         while (time_before(jiffies, delay))
275                 if (wait_event_timeout(ec->wait, ec_check_ibf0(ec),
276                                         msecs_to_jiffies(1)))
277                         return 0;
278         return -ETIME;
279 }
280
281 static int acpi_ec_transaction(struct acpi_ec *ec, struct transaction *t)
282 {
283         int status;
284         u32 glk;
285         if (!ec || (!t) || (t->wlen && !t->wdata) || (t->rlen && !t->rdata))
286                 return -EINVAL;
287         if (t->rdata)
288                 memset(t->rdata, 0, t->rlen);
289         mutex_lock(&ec->lock);
290         if (test_bit(EC_FLAGS_BLOCKED, &ec->flags)) {
291                 status = -EINVAL;
292                 goto unlock;
293         }
294         if (ec->global_lock) {
295                 status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk);
296                 if (ACPI_FAILURE(status)) {
297                         status = -ENODEV;
298                         goto unlock;
299                 }
300         }
301         if (ec_wait_ibf0(ec)) {
302                 pr_err(PREFIX "input buffer is not empty, "
303                                 "aborting transaction\n");
304                 status = -ETIME;
305                 goto end;
306         }
307         pr_debug(PREFIX "transaction start\n");
308         /* disable GPE during transaction if storm is detected */
309         if (test_bit(EC_FLAGS_GPE_STORM, &ec->flags)) {
310                 /* It has to be disabled, so that it doesn't trigger. */
311                 acpi_disable_gpe(NULL, ec->gpe);
312         }
313
314         status = acpi_ec_transaction_unlocked(ec, t);
315
316         /* check if we received SCI during transaction */
317         ec_check_sci_sync(ec, acpi_ec_read_status(ec));
318         if (test_bit(EC_FLAGS_GPE_STORM, &ec->flags)) {
319                 msleep(1);
320                 /* It is safe to enable the GPE outside of the transaction. */
321                 acpi_enable_gpe(NULL, ec->gpe);
322         } else if (t->irq_count > ACPI_EC_STORM_THRESHOLD) {
323                 pr_info(PREFIX "GPE storm detected, "
324                         "transactions will use polling mode\n");
325                 set_bit(EC_FLAGS_GPE_STORM, &ec->flags);
326         }
327         pr_debug(PREFIX "transaction end\n");
328 end:
329         if (ec->global_lock)
330                 acpi_release_global_lock(glk);
331 unlock:
332         mutex_unlock(&ec->lock);
333         return status;
334 }
335
336 static int acpi_ec_burst_enable(struct acpi_ec *ec)
337 {
338         u8 d;
339         struct transaction t = {.command = ACPI_EC_BURST_ENABLE,
340                                 .wdata = NULL, .rdata = &d,
341                                 .wlen = 0, .rlen = 1};
342
343         return acpi_ec_transaction(ec, &t);
344 }
345
346 static int acpi_ec_burst_disable(struct acpi_ec *ec)
347 {
348         struct transaction t = {.command = ACPI_EC_BURST_DISABLE,
349                                 .wdata = NULL, .rdata = NULL,
350                                 .wlen = 0, .rlen = 0};
351
352         return (acpi_ec_read_status(ec) & ACPI_EC_FLAG_BURST) ?
353                                 acpi_ec_transaction(ec, &t) : 0;
354 }
355
356 static int acpi_ec_read(struct acpi_ec *ec, u8 address, u8 * data)
357 {
358         int result;
359         u8 d;
360         struct transaction t = {.command = ACPI_EC_COMMAND_READ,
361                                 .wdata = &address, .rdata = &d,
362                                 .wlen = 1, .rlen = 1};
363
364         result = acpi_ec_transaction(ec, &t);
365         *data = d;
366         return result;
367 }
368
369 static int acpi_ec_write(struct acpi_ec *ec, u8 address, u8 data)
370 {
371         u8 wdata[2] = { address, data };
372         struct transaction t = {.command = ACPI_EC_COMMAND_WRITE,
373                                 .wdata = wdata, .rdata = NULL,
374                                 .wlen = 2, .rlen = 0};
375
376         return acpi_ec_transaction(ec, &t);
377 }
378
379 /*
380  * Externally callable EC access functions. For now, assume 1 EC only
381  */
382 int ec_burst_enable(void)
383 {
384         if (!first_ec)
385                 return -ENODEV;
386         return acpi_ec_burst_enable(first_ec);
387 }
388
389 EXPORT_SYMBOL(ec_burst_enable);
390
391 int ec_burst_disable(void)
392 {
393         if (!first_ec)
394                 return -ENODEV;
395         return acpi_ec_burst_disable(first_ec);
396 }
397
398 EXPORT_SYMBOL(ec_burst_disable);
399
400 int ec_read(u8 addr, u8 * val)
401 {
402         int err;
403         u8 temp_data;
404
405         if (!first_ec)
406                 return -ENODEV;
407
408         err = acpi_ec_read(first_ec, addr, &temp_data);
409
410         if (!err) {
411                 *val = temp_data;
412                 return 0;
413         } else
414                 return err;
415 }
416
417 EXPORT_SYMBOL(ec_read);
418
419 int ec_write(u8 addr, u8 val)
420 {
421         int err;
422
423         if (!first_ec)
424                 return -ENODEV;
425
426         err = acpi_ec_write(first_ec, addr, val);
427
428         return err;
429 }
430
431 EXPORT_SYMBOL(ec_write);
432
433 int ec_transaction(u8 command,
434                    const u8 * wdata, unsigned wdata_len,
435                    u8 * rdata, unsigned rdata_len)
436 {
437         struct transaction t = {.command = command,
438                                 .wdata = wdata, .rdata = rdata,
439                                 .wlen = wdata_len, .rlen = rdata_len};
440         if (!first_ec)
441                 return -ENODEV;
442
443         return acpi_ec_transaction(first_ec, &t);
444 }
445
446 EXPORT_SYMBOL(ec_transaction);
447
448 void acpi_ec_block_transactions(void)
449 {
450         struct acpi_ec *ec = first_ec;
451
452         if (!ec)
453                 return;
454
455         mutex_lock(&ec->lock);
456         /* Prevent transactions from being carried out */
457         set_bit(EC_FLAGS_BLOCKED, &ec->flags);
458         mutex_unlock(&ec->lock);
459 }
460
461 void acpi_ec_unblock_transactions(void)
462 {
463         struct acpi_ec *ec = first_ec;
464
465         if (!ec)
466                 return;
467
468         mutex_lock(&ec->lock);
469         /* Allow transactions to be carried out again */
470         clear_bit(EC_FLAGS_BLOCKED, &ec->flags);
471         mutex_unlock(&ec->lock);
472 }
473
474 void acpi_ec_unblock_transactions_early(void)
475 {
476         /*
477          * Allow transactions to happen again (this function is called from
478          * atomic context during wakeup, so we don't need to acquire the mutex).
479          */
480         if (first_ec)
481                 clear_bit(EC_FLAGS_BLOCKED, &first_ec->flags);
482 }
483
484 static int acpi_ec_query_unlocked(struct acpi_ec *ec, u8 * data)
485 {
486         int result;
487         u8 d;
488         struct transaction t = {.command = ACPI_EC_COMMAND_QUERY,
489                                 .wdata = NULL, .rdata = &d,
490                                 .wlen = 0, .rlen = 1};
491         if (!ec || !data)
492                 return -EINVAL;
493         /*
494          * Query the EC to find out which _Qxx method we need to evaluate.
495          * Note that successful completion of the query causes the ACPI_EC_SCI
496          * bit to be cleared (and thus clearing the interrupt source).
497          */
498         result = acpi_ec_transaction_unlocked(ec, &t);
499         if (result)
500                 return result;
501         if (!d)
502                 return -ENODATA;
503         *data = d;
504         return 0;
505 }
506
507 /* --------------------------------------------------------------------------
508                                 Event Management
509    -------------------------------------------------------------------------- */
510 int acpi_ec_add_query_handler(struct acpi_ec *ec, u8 query_bit,
511                               acpi_handle handle, acpi_ec_query_func func,
512                               void *data)
513 {
514         struct acpi_ec_query_handler *handler =
515             kzalloc(sizeof(struct acpi_ec_query_handler), GFP_KERNEL);
516         if (!handler)
517                 return -ENOMEM;
518
519         handler->query_bit = query_bit;
520         handler->handle = handle;
521         handler->func = func;
522         handler->data = data;
523         mutex_lock(&ec->lock);
524         list_add(&handler->node, &ec->list);
525         mutex_unlock(&ec->lock);
526         return 0;
527 }
528
529 EXPORT_SYMBOL_GPL(acpi_ec_add_query_handler);
530
531 void acpi_ec_remove_query_handler(struct acpi_ec *ec, u8 query_bit)
532 {
533         struct acpi_ec_query_handler *handler, *tmp;
534         mutex_lock(&ec->lock);
535         list_for_each_entry_safe(handler, tmp, &ec->list, node) {
536                 if (query_bit == handler->query_bit) {
537                         list_del(&handler->node);
538                         kfree(handler);
539                 }
540         }
541         mutex_unlock(&ec->lock);
542 }
543
544 EXPORT_SYMBOL_GPL(acpi_ec_remove_query_handler);
545
546 static void acpi_ec_run(void *cxt)
547 {
548         struct acpi_ec_query_handler *handler = cxt;
549         if (!handler)
550                 return;
551         pr_debug(PREFIX "start query execution\n");
552         if (handler->func)
553                 handler->func(handler->data);
554         else if (handler->handle)
555                 acpi_evaluate_object(handler->handle, NULL, NULL, NULL);
556         pr_debug(PREFIX "stop query execution\n");
557         kfree(handler);
558 }
559
560 static int acpi_ec_sync_query(struct acpi_ec *ec)
561 {
562         u8 value = 0;
563         int status;
564         struct acpi_ec_query_handler *handler, *copy;
565         if ((status = acpi_ec_query_unlocked(ec, &value)))
566                 return status;
567         list_for_each_entry(handler, &ec->list, node) {
568                 if (value == handler->query_bit) {
569                         /* have custom handler for this bit */
570                         copy = kmalloc(sizeof(*handler), GFP_KERNEL);
571                         if (!copy)
572                                 return -ENOMEM;
573                         memcpy(copy, handler, sizeof(*copy));
574                         pr_debug(PREFIX "push query execution (0x%2x) on queue\n", value);
575                         return acpi_os_execute((copy->func) ?
576                                 OSL_NOTIFY_HANDLER : OSL_GPE_HANDLER,
577                                 acpi_ec_run, copy);
578                 }
579         }
580         return 0;
581 }
582
583 static void acpi_ec_gpe_query(void *ec_cxt)
584 {
585         struct acpi_ec *ec = ec_cxt;
586         if (!ec)
587                 return;
588         mutex_lock(&ec->lock);
589         acpi_ec_sync_query(ec);
590         mutex_unlock(&ec->lock);
591 }
592
593 static int ec_check_sci(struct acpi_ec *ec, u8 state)
594 {
595         if (state & ACPI_EC_FLAG_SCI) {
596                 if (!test_and_set_bit(EC_FLAGS_QUERY_PENDING, &ec->flags)) {
597                         pr_debug(PREFIX "push gpe query to the queue\n");
598                         return acpi_os_execute(OSL_NOTIFY_HANDLER,
599                                 acpi_ec_gpe_query, ec);
600                 }
601         }
602         return 0;
603 }
604
605 static u32 acpi_ec_gpe_handler(acpi_handle gpe_device,
606         u32 gpe_number, void *data)
607 {
608         struct acpi_ec *ec = data;
609
610         pr_debug(PREFIX "~~~> interrupt\n");
611
612         advance_transaction(ec, acpi_ec_read_status(ec));
613         if (ec_transaction_done(ec) &&
614             (acpi_ec_read_status(ec) & ACPI_EC_FLAG_IBF) == 0) {
615                 wake_up(&ec->wait);
616                 ec_check_sci(ec, acpi_ec_read_status(ec));
617         }
618         return ACPI_INTERRUPT_HANDLED | ACPI_REENABLE_GPE;
619 }
620
621 /* --------------------------------------------------------------------------
622                              Address Space Management
623    -------------------------------------------------------------------------- */
624
625 static acpi_status
626 acpi_ec_space_handler(u32 function, acpi_physical_address address,
627                       u32 bits, u64 *value64,
628                       void *handler_context, void *region_context)
629 {
630         struct acpi_ec *ec = handler_context;
631         int result = 0, i, bytes = bits / 8;
632         u8 *value = (u8 *)value64;
633
634         if ((address > 0xFF) || !value || !handler_context)
635                 return AE_BAD_PARAMETER;
636
637         if (function != ACPI_READ && function != ACPI_WRITE)
638                 return AE_BAD_PARAMETER;
639
640         if (EC_FLAGS_MSI || bits > 8)
641                 acpi_ec_burst_enable(ec);
642
643         for (i = 0; i < bytes; ++i, ++address, ++value)
644                 result = (function == ACPI_READ) ?
645                         acpi_ec_read(ec, address, value) :
646                         acpi_ec_write(ec, address, *value);
647
648         if (EC_FLAGS_MSI || bits > 8)
649                 acpi_ec_burst_disable(ec);
650
651         switch (result) {
652         case -EINVAL:
653                 return AE_BAD_PARAMETER;
654                 break;
655         case -ENODEV:
656                 return AE_NOT_FOUND;
657                 break;
658         case -ETIME:
659                 return AE_TIME;
660                 break;
661         default:
662                 return AE_OK;
663         }
664 }
665
666 /* --------------------------------------------------------------------------
667                                Driver Interface
668    -------------------------------------------------------------------------- */
669 static acpi_status
670 ec_parse_io_ports(struct acpi_resource *resource, void *context);
671
672 static struct acpi_ec *make_acpi_ec(void)
673 {
674         struct acpi_ec *ec = kzalloc(sizeof(struct acpi_ec), GFP_KERNEL);
675         if (!ec)
676                 return NULL;
677         ec->flags = 1 << EC_FLAGS_QUERY_PENDING;
678         mutex_init(&ec->lock);
679         init_waitqueue_head(&ec->wait);
680         INIT_LIST_HEAD(&ec->list);
681         spin_lock_init(&ec->curr_lock);
682         return ec;
683 }
684
685 static acpi_status
686 acpi_ec_register_query_methods(acpi_handle handle, u32 level,
687                                void *context, void **return_value)
688 {
689         char node_name[5];
690         struct acpi_buffer buffer = { sizeof(node_name), node_name };
691         struct acpi_ec *ec = context;
692         int value = 0;
693         acpi_status status;
694
695         status = acpi_get_name(handle, ACPI_SINGLE_NAME, &buffer);
696
697         if (ACPI_SUCCESS(status) && sscanf(node_name, "_Q%x", &value) == 1) {
698                 acpi_ec_add_query_handler(ec, value, handle, NULL, NULL);
699         }
700         return AE_OK;
701 }
702
703 static acpi_status
704 ec_parse_device(acpi_handle handle, u32 Level, void *context, void **retval)
705 {
706         acpi_status status;
707         unsigned long long tmp = 0;
708
709         struct acpi_ec *ec = context;
710
711         /* clear addr values, ec_parse_io_ports depend on it */
712         ec->command_addr = ec->data_addr = 0;
713
714         status = acpi_walk_resources(handle, METHOD_NAME__CRS,
715                                      ec_parse_io_ports, ec);
716         if (ACPI_FAILURE(status))
717                 return status;
718
719         /* Get GPE bit assignment (EC events). */
720         /* TODO: Add support for _GPE returning a package */
721         status = acpi_evaluate_integer(handle, "_GPE", NULL, &tmp);
722         if (ACPI_FAILURE(status))
723                 return status;
724         ec->gpe = tmp;
725         /* Use the global lock for all EC transactions? */
726         tmp = 0;
727         acpi_evaluate_integer(handle, "_GLK", NULL, &tmp);
728         ec->global_lock = tmp;
729         ec->handle = handle;
730         return AE_CTRL_TERMINATE;
731 }
732
733 static int ec_install_handlers(struct acpi_ec *ec)
734 {
735         acpi_status status;
736         if (test_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags))
737                 return 0;
738         status = acpi_install_gpe_handler(NULL, ec->gpe,
739                                   ACPI_GPE_EDGE_TRIGGERED,
740                                   &acpi_ec_gpe_handler, ec);
741         if (ACPI_FAILURE(status))
742                 return -ENODEV;
743
744         acpi_enable_gpe(NULL, ec->gpe);
745         status = acpi_install_address_space_handler(ec->handle,
746                                                     ACPI_ADR_SPACE_EC,
747                                                     &acpi_ec_space_handler,
748                                                     NULL, ec);
749         if (ACPI_FAILURE(status)) {
750                 if (status == AE_NOT_FOUND) {
751                         /*
752                          * Maybe OS fails in evaluating the _REG object.
753                          * The AE_NOT_FOUND error will be ignored and OS
754                          * continue to initialize EC.
755                          */
756                         printk(KERN_ERR "Fail in evaluating the _REG object"
757                                 " of EC device. Broken bios is suspected.\n");
758                 } else {
759                         acpi_remove_gpe_handler(NULL, ec->gpe,
760                                 &acpi_ec_gpe_handler);
761                         acpi_disable_gpe(NULL, ec->gpe);
762                         return -ENODEV;
763                 }
764         }
765
766         set_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags);
767         return 0;
768 }
769
770 static void ec_remove_handlers(struct acpi_ec *ec)
771 {
772         acpi_disable_gpe(NULL, ec->gpe);
773         if (ACPI_FAILURE(acpi_remove_address_space_handler(ec->handle,
774                                 ACPI_ADR_SPACE_EC, &acpi_ec_space_handler)))
775                 pr_err(PREFIX "failed to remove space handler\n");
776         if (ACPI_FAILURE(acpi_remove_gpe_handler(NULL, ec->gpe,
777                                 &acpi_ec_gpe_handler)))
778                 pr_err(PREFIX "failed to remove gpe handler\n");
779         clear_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags);
780 }
781
782 static int acpi_ec_add(struct acpi_device *device)
783 {
784         struct acpi_ec *ec = NULL;
785         int ret;
786
787         strcpy(acpi_device_name(device), ACPI_EC_DEVICE_NAME);
788         strcpy(acpi_device_class(device), ACPI_EC_CLASS);
789
790         /* Check for boot EC */
791         if (boot_ec &&
792             (boot_ec->handle == device->handle ||
793              boot_ec->handle == ACPI_ROOT_OBJECT)) {
794                 ec = boot_ec;
795                 boot_ec = NULL;
796         } else {
797                 ec = make_acpi_ec();
798                 if (!ec)
799                         return -ENOMEM;
800         }
801         if (ec_parse_device(device->handle, 0, ec, NULL) !=
802                 AE_CTRL_TERMINATE) {
803                         kfree(ec);
804                         return -EINVAL;
805         }
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
830 static 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
855 static acpi_status
856 ec_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
878 int __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
889 static 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 */
895 static 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 */
902 static 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 */
909 static 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
917 static 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_flag_msi, "Quanta hardware", {
936         DMI_MATCH(DMI_SYS_VENDOR, "Quanta"),
937         DMI_MATCH(DMI_PRODUCT_NAME, "TW8/SW8/DW8"),}, NULL},
938         {
939         ec_flag_msi, "Quanta hardware", {
940         DMI_MATCH(DMI_SYS_VENDOR, "Quanta"),
941         DMI_MATCH(DMI_PRODUCT_NAME, "TW9/SW9"),}, NULL},
942         {
943         ec_validate_ecdt, "ASUS hardware", {
944         DMI_MATCH(DMI_BIOS_VENDOR, "ASUS") }, NULL},
945         {
946         ec_validate_ecdt, "ASUS hardware", {
947         DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTeK Computer Inc.") }, NULL},
948         {},
949 };
950
951
952 int __init acpi_ec_ecdt_probe(void)
953 {
954         acpi_status status;
955         struct acpi_ec *saved_ec = NULL;
956         struct acpi_table_ecdt *ecdt_ptr;
957
958         boot_ec = make_acpi_ec();
959         if (!boot_ec)
960                 return -ENOMEM;
961         /*
962          * Generate a boot ec context
963          */
964         dmi_check_system(ec_dmi_table);
965         status = acpi_get_table(ACPI_SIG_ECDT, 1,
966                                 (struct acpi_table_header **)&ecdt_ptr);
967         if (ACPI_SUCCESS(status)) {
968                 pr_info(PREFIX "EC description table is found, configuring boot EC\n");
969                 boot_ec->command_addr = ecdt_ptr->control.address;
970                 boot_ec->data_addr = ecdt_ptr->data.address;
971                 boot_ec->gpe = ecdt_ptr->gpe;
972                 boot_ec->handle = ACPI_ROOT_OBJECT;
973                 acpi_get_handle(ACPI_ROOT_OBJECT, ecdt_ptr->id, &boot_ec->handle);
974                 /* Don't trust ECDT, which comes from ASUSTek */
975                 if (!EC_FLAGS_VALIDATE_ECDT)
976                         goto install;
977                 saved_ec = kmemdup(boot_ec, sizeof(struct acpi_ec), GFP_KERNEL);
978                 if (!saved_ec)
979                         return -ENOMEM;
980         /* fall through */
981         }
982
983         if (EC_FLAGS_SKIP_DSDT_SCAN)
984                 return -ENODEV;
985
986         /* This workaround is needed only on some broken machines,
987          * which require early EC, but fail to provide ECDT */
988         printk(KERN_DEBUG PREFIX "Look up EC in DSDT\n");
989         status = acpi_get_devices(ec_device_ids[0].id, ec_parse_device,
990                                         boot_ec, NULL);
991         /* Check that acpi_get_devices actually find something */
992         if (ACPI_FAILURE(status) || !boot_ec->handle)
993                 goto error;
994         if (saved_ec) {
995                 /* try to find good ECDT from ASUSTek */
996                 if (saved_ec->command_addr != boot_ec->command_addr ||
997                     saved_ec->data_addr != boot_ec->data_addr ||
998                     saved_ec->gpe != boot_ec->gpe ||
999                     saved_ec->handle != boot_ec->handle)
1000                         pr_info(PREFIX "ASUSTek keeps feeding us with broken "
1001                         "ECDT tables, which are very hard to workaround. "
1002                         "Trying to use DSDT EC info instead. Please send "
1003                         "output of acpidump to linux-acpi@vger.kernel.org\n");
1004                 kfree(saved_ec);
1005                 saved_ec = NULL;
1006         } else {
1007                 /* We really need to limit this workaround, the only ASUS,
1008                 * which needs it, has fake EC._INI method, so use it as flag.
1009                 * Keep boot_ec struct as it will be needed soon.
1010                 */
1011                 acpi_handle dummy;
1012                 if (!dmi_name_in_vendors("ASUS") ||
1013                     ACPI_FAILURE(acpi_get_handle(boot_ec->handle, "_INI",
1014                                                         &dummy)))
1015                         return -ENODEV;
1016         }
1017 install:
1018         if (!ec_install_handlers(boot_ec)) {
1019                 first_ec = boot_ec;
1020                 return 0;
1021         }
1022 error:
1023         kfree(boot_ec);
1024         boot_ec = NULL;
1025         return -ENODEV;
1026 }
1027
1028 static struct acpi_driver acpi_ec_driver = {
1029         .name = "ec",
1030         .class = ACPI_EC_CLASS,
1031         .ids = ec_device_ids,
1032         .ops = {
1033                 .add = acpi_ec_add,
1034                 .remove = acpi_ec_remove,
1035                 },
1036 };
1037
1038 int __init acpi_ec_init(void)
1039 {
1040         int result = 0;
1041
1042         /* Now register the driver for the EC */
1043         result = acpi_bus_register_driver(&acpi_ec_driver);
1044         if (result < 0)
1045                 return -ENODEV;
1046
1047         return result;
1048 }
1049
1050 /* EC driver currently not unloadable */
1051 #if 0
1052 static void __exit acpi_ec_exit(void)
1053 {
1054
1055         acpi_bus_unregister_driver(&acpi_ec_driver);
1056         return;
1057 }
1058 #endif  /* 0 */