include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit...
[safe/jmp/linux-2.6] / 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/proc_fs.h>
38 #include <linux/seq_file.h>
39 #include <linux/interrupt.h>
40 #include <linux/list.h>
41 #include <linux/spinlock.h>
42 #include <linux/slab.h>
43 #include <asm/io.h>
44 #include <acpi/acpi_bus.h>
45 #include <acpi/acpi_drivers.h>
46 #include <linux/dmi.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 #define PREFIX                          "ACPI: EC: "
53
54 /* EC status register */
55 #define ACPI_EC_FLAG_OBF        0x01    /* Output buffer full */
56 #define ACPI_EC_FLAG_IBF        0x02    /* Input buffer full */
57 #define ACPI_EC_FLAG_BURST      0x10    /* burst mode */
58 #define ACPI_EC_FLAG_SCI        0x20    /* EC-SCI occurred */
59
60 /* EC commands */
61 enum ec_command {
62         ACPI_EC_COMMAND_READ = 0x80,
63         ACPI_EC_COMMAND_WRITE = 0x81,
64         ACPI_EC_BURST_ENABLE = 0x82,
65         ACPI_EC_BURST_DISABLE = 0x83,
66         ACPI_EC_COMMAND_QUERY = 0x84,
67 };
68
69 #define ACPI_EC_DELAY           500     /* Wait 500ms max. during EC ops */
70 #define ACPI_EC_UDELAY_GLK      1000    /* Wait 1ms max. to get global lock */
71 #define ACPI_EC_CDELAY          10      /* Wait 10us before polling EC */
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_FROZEN,                /* Transactions are suspended */
83 };
84
85 /* If we find an EC via the ECDT, we need to keep a ptr to its context */
86 /* External interfaces use first EC only, so remember */
87 typedef int (*acpi_ec_query_func) (void *data);
88
89 struct acpi_ec_query_handler {
90         struct list_head node;
91         acpi_ec_query_func func;
92         acpi_handle handle;
93         void *data;
94         u8 query_bit;
95 };
96
97 struct transaction {
98         const u8 *wdata;
99         u8 *rdata;
100         unsigned short irq_count;
101         u8 command;
102         u8 wi;
103         u8 ri;
104         u8 wlen;
105         u8 rlen;
106         bool done;
107 };
108
109 static struct acpi_ec {
110         acpi_handle handle;
111         unsigned long gpe;
112         unsigned long command_addr;
113         unsigned long data_addr;
114         unsigned long global_lock;
115         unsigned long flags;
116         struct mutex lock;
117         wait_queue_head_t wait;
118         struct list_head list;
119         struct transaction *curr;
120         spinlock_t curr_lock;
121 } *boot_ec, *first_ec;
122
123 static int EC_FLAGS_MSI; /* Out-of-spec MSI controller */
124 static int EC_FLAGS_VALIDATE_ECDT; /* ASUStec ECDTs need to be validated */
125 static int EC_FLAGS_SKIP_DSDT_SCAN; /* Not all BIOS survive early DSDT scan */
126
127 /* --------------------------------------------------------------------------
128                              Transaction Management
129    -------------------------------------------------------------------------- */
130
131 static inline u8 acpi_ec_read_status(struct acpi_ec *ec)
132 {
133         u8 x = inb(ec->command_addr);
134         pr_debug(PREFIX "---> status = 0x%2.2x\n", x);
135         return x;
136 }
137
138 static inline u8 acpi_ec_read_data(struct acpi_ec *ec)
139 {
140         u8 x = inb(ec->data_addr);
141         pr_debug(PREFIX "---> data = 0x%2.2x\n", x);
142         return x;
143 }
144
145 static inline void acpi_ec_write_cmd(struct acpi_ec *ec, u8 command)
146 {
147         pr_debug(PREFIX "<--- command = 0x%2.2x\n", command);
148         outb(command, ec->command_addr);
149 }
150
151 static inline void acpi_ec_write_data(struct acpi_ec *ec, u8 data)
152 {
153         pr_debug(PREFIX "<--- data = 0x%2.2x\n", data);
154         outb(data, ec->data_addr);
155 }
156
157 static int ec_transaction_done(struct acpi_ec *ec)
158 {
159         unsigned long flags;
160         int ret = 0;
161         spin_lock_irqsave(&ec->curr_lock, flags);
162         if (!ec->curr || ec->curr->done)
163                 ret = 1;
164         spin_unlock_irqrestore(&ec->curr_lock, flags);
165         return ret;
166 }
167
168 static void start_transaction(struct acpi_ec *ec)
169 {
170         ec->curr->irq_count = ec->curr->wi = ec->curr->ri = 0;
171         ec->curr->done = false;
172         acpi_ec_write_cmd(ec, ec->curr->command);
173 }
174
175 static void advance_transaction(struct acpi_ec *ec, u8 status)
176 {
177         unsigned long flags;
178         spin_lock_irqsave(&ec->curr_lock, flags);
179         if (!ec->curr)
180                 goto unlock;
181         if (ec->curr->wlen > ec->curr->wi) {
182                 if ((status & ACPI_EC_FLAG_IBF) == 0)
183                         acpi_ec_write_data(ec,
184                                 ec->curr->wdata[ec->curr->wi++]);
185                 else
186                         goto err;
187         } else if (ec->curr->rlen > ec->curr->ri) {
188                 if ((status & ACPI_EC_FLAG_OBF) == 1) {
189                         ec->curr->rdata[ec->curr->ri++] = acpi_ec_read_data(ec);
190                         if (ec->curr->rlen == ec->curr->ri)
191                                 ec->curr->done = true;
192                 } else
193                         goto err;
194         } else if (ec->curr->wlen == ec->curr->wi &&
195                    (status & ACPI_EC_FLAG_IBF) == 0)
196                 ec->curr->done = true;
197         goto unlock;
198 err:
199         /* false interrupt, state didn't change */
200         if (in_interrupt())
201                 ++ec->curr->irq_count;
202 unlock:
203         spin_unlock_irqrestore(&ec->curr_lock, flags);
204 }
205
206 static int acpi_ec_sync_query(struct acpi_ec *ec);
207
208 static int ec_check_sci_sync(struct acpi_ec *ec, u8 state)
209 {
210         if (state & ACPI_EC_FLAG_SCI) {
211                 if (!test_and_set_bit(EC_FLAGS_QUERY_PENDING, &ec->flags))
212                         return acpi_ec_sync_query(ec);
213         }
214         return 0;
215 }
216
217 static int ec_poll(struct acpi_ec *ec)
218 {
219         unsigned long flags;
220         int repeat = 2; /* number of command restarts */
221         while (repeat--) {
222                 unsigned long delay = jiffies +
223                         msecs_to_jiffies(ACPI_EC_DELAY);
224                 do {
225                         /* don't sleep with disabled interrupts */
226                         if (EC_FLAGS_MSI || irqs_disabled()) {
227                                 udelay(ACPI_EC_MSI_UDELAY);
228                                 if (ec_transaction_done(ec))
229                                         return 0;
230                         } else {
231                                 if (wait_event_timeout(ec->wait,
232                                                 ec_transaction_done(ec),
233                                                 msecs_to_jiffies(1)))
234                                         return 0;
235                         }
236                         advance_transaction(ec, acpi_ec_read_status(ec));
237                 } while (time_before(jiffies, delay));
238                 if (acpi_ec_read_status(ec) & ACPI_EC_FLAG_IBF)
239                         break;
240                 pr_debug(PREFIX "controller reset, restart transaction\n");
241                 spin_lock_irqsave(&ec->curr_lock, flags);
242                 start_transaction(ec);
243                 spin_unlock_irqrestore(&ec->curr_lock, flags);
244         }
245         return -ETIME;
246 }
247
248 static int acpi_ec_transaction_unlocked(struct acpi_ec *ec,
249                                         struct transaction *t)
250 {
251         unsigned long tmp;
252         int ret = 0;
253         if (EC_FLAGS_MSI)
254                 udelay(ACPI_EC_MSI_UDELAY);
255         /* start transaction */
256         spin_lock_irqsave(&ec->curr_lock, tmp);
257         /* following two actions should be kept atomic */
258         ec->curr = t;
259         start_transaction(ec);
260         if (ec->curr->command == ACPI_EC_COMMAND_QUERY)
261                 clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags);
262         spin_unlock_irqrestore(&ec->curr_lock, tmp);
263         ret = ec_poll(ec);
264         spin_lock_irqsave(&ec->curr_lock, tmp);
265         ec->curr = NULL;
266         spin_unlock_irqrestore(&ec->curr_lock, tmp);
267         return ret;
268 }
269
270 static int ec_check_ibf0(struct acpi_ec *ec)
271 {
272         u8 status = acpi_ec_read_status(ec);
273         return (status & ACPI_EC_FLAG_IBF) == 0;
274 }
275
276 static int ec_wait_ibf0(struct acpi_ec *ec)
277 {
278         unsigned long delay = jiffies + msecs_to_jiffies(ACPI_EC_DELAY);
279         /* interrupt wait manually if GPE mode is not active */
280         while (time_before(jiffies, delay))
281                 if (wait_event_timeout(ec->wait, ec_check_ibf0(ec),
282                                         msecs_to_jiffies(1)))
283                         return 0;
284         return -ETIME;
285 }
286
287 static int acpi_ec_transaction(struct acpi_ec *ec, struct transaction *t)
288 {
289         int status;
290         u32 glk;
291         if (!ec || (!t) || (t->wlen && !t->wdata) || (t->rlen && !t->rdata))
292                 return -EINVAL;
293         if (t->rdata)
294                 memset(t->rdata, 0, t->rlen);
295         mutex_lock(&ec->lock);
296         if (test_bit(EC_FLAGS_FROZEN, &ec->flags)) {
297                 status = -EINVAL;
298                 goto unlock;
299         }
300         if (ec->global_lock) {
301                 status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk);
302                 if (ACPI_FAILURE(status)) {
303                         status = -ENODEV;
304                         goto unlock;
305                 }
306         }
307         if (ec_wait_ibf0(ec)) {
308                 pr_err(PREFIX "input buffer is not empty, "
309                                 "aborting transaction\n");
310                 status = -ETIME;
311                 goto end;
312         }
313         pr_debug(PREFIX "transaction start\n");
314         /* disable GPE during transaction if storm is detected */
315         if (test_bit(EC_FLAGS_GPE_STORM, &ec->flags)) {
316                 /*
317                  * It has to be disabled at the hardware level regardless of the
318                  * GPE reference counting, so that it doesn't trigger.
319                  */
320                 acpi_set_gpe(NULL, ec->gpe, ACPI_GPE_DISABLE);
321         }
322
323         status = acpi_ec_transaction_unlocked(ec, t);
324
325         /* check if we received SCI during transaction */
326         ec_check_sci_sync(ec, acpi_ec_read_status(ec));
327         if (test_bit(EC_FLAGS_GPE_STORM, &ec->flags)) {
328                 msleep(1);
329                 /*
330                  * It is safe to enable the GPE outside of the transaction.  Use
331                  * acpi_set_gpe() for that, since we used it to disable the GPE
332                  * above.
333                  */
334                 acpi_set_gpe(NULL, ec->gpe, ACPI_GPE_ENABLE);
335         } else if (t->irq_count > ACPI_EC_STORM_THRESHOLD) {
336                 pr_info(PREFIX "GPE storm detected, "
337                         "transactions will use polling mode\n");
338                 set_bit(EC_FLAGS_GPE_STORM, &ec->flags);
339         }
340         pr_debug(PREFIX "transaction end\n");
341 end:
342         if (ec->global_lock)
343                 acpi_release_global_lock(glk);
344 unlock:
345         mutex_unlock(&ec->lock);
346         return status;
347 }
348
349 static int acpi_ec_burst_enable(struct acpi_ec *ec)
350 {
351         u8 d;
352         struct transaction t = {.command = ACPI_EC_BURST_ENABLE,
353                                 .wdata = NULL, .rdata = &d,
354                                 .wlen = 0, .rlen = 1};
355
356         return acpi_ec_transaction(ec, &t);
357 }
358
359 static int acpi_ec_burst_disable(struct acpi_ec *ec)
360 {
361         struct transaction t = {.command = ACPI_EC_BURST_DISABLE,
362                                 .wdata = NULL, .rdata = NULL,
363                                 .wlen = 0, .rlen = 0};
364
365         return (acpi_ec_read_status(ec) & ACPI_EC_FLAG_BURST) ?
366                                 acpi_ec_transaction(ec, &t) : 0;
367 }
368
369 static int acpi_ec_read(struct acpi_ec *ec, u8 address, u8 * data)
370 {
371         int result;
372         u8 d;
373         struct transaction t = {.command = ACPI_EC_COMMAND_READ,
374                                 .wdata = &address, .rdata = &d,
375                                 .wlen = 1, .rlen = 1};
376
377         result = acpi_ec_transaction(ec, &t);
378         *data = d;
379         return result;
380 }
381
382 static int acpi_ec_write(struct acpi_ec *ec, u8 address, u8 data)
383 {
384         u8 wdata[2] = { address, data };
385         struct transaction t = {.command = ACPI_EC_COMMAND_WRITE,
386                                 .wdata = wdata, .rdata = NULL,
387                                 .wlen = 2, .rlen = 0};
388
389         return acpi_ec_transaction(ec, &t);
390 }
391
392 /*
393  * Externally callable EC access functions. For now, assume 1 EC only
394  */
395 int ec_burst_enable(void)
396 {
397         if (!first_ec)
398                 return -ENODEV;
399         return acpi_ec_burst_enable(first_ec);
400 }
401
402 EXPORT_SYMBOL(ec_burst_enable);
403
404 int ec_burst_disable(void)
405 {
406         if (!first_ec)
407                 return -ENODEV;
408         return acpi_ec_burst_disable(first_ec);
409 }
410
411 EXPORT_SYMBOL(ec_burst_disable);
412
413 int ec_read(u8 addr, u8 * val)
414 {
415         int err;
416         u8 temp_data;
417
418         if (!first_ec)
419                 return -ENODEV;
420
421         err = acpi_ec_read(first_ec, addr, &temp_data);
422
423         if (!err) {
424                 *val = temp_data;
425                 return 0;
426         } else
427                 return err;
428 }
429
430 EXPORT_SYMBOL(ec_read);
431
432 int ec_write(u8 addr, u8 val)
433 {
434         int err;
435
436         if (!first_ec)
437                 return -ENODEV;
438
439         err = acpi_ec_write(first_ec, addr, val);
440
441         return err;
442 }
443
444 EXPORT_SYMBOL(ec_write);
445
446 int ec_transaction(u8 command,
447                    const u8 * wdata, unsigned wdata_len,
448                    u8 * rdata, unsigned rdata_len,
449                    int force_poll)
450 {
451         struct transaction t = {.command = command,
452                                 .wdata = wdata, .rdata = rdata,
453                                 .wlen = wdata_len, .rlen = rdata_len};
454         if (!first_ec)
455                 return -ENODEV;
456
457         return acpi_ec_transaction(first_ec, &t);
458 }
459
460 EXPORT_SYMBOL(ec_transaction);
461
462 void acpi_ec_suspend_transactions(void)
463 {
464         struct acpi_ec *ec = first_ec;
465
466         if (!ec)
467                 return;
468
469         mutex_lock(&ec->lock);
470         /* Prevent transactions from being carried out */
471         set_bit(EC_FLAGS_FROZEN, &ec->flags);
472         mutex_unlock(&ec->lock);
473 }
474
475 void acpi_ec_resume_transactions(void)
476 {
477         struct acpi_ec *ec = first_ec;
478
479         if (!ec)
480                 return;
481
482         mutex_lock(&ec->lock);
483         /* Allow transactions to be carried out again */
484         clear_bit(EC_FLAGS_FROZEN, &ec->flags);
485         mutex_unlock(&ec->lock);
486 }
487
488 static int acpi_ec_query_unlocked(struct acpi_ec *ec, u8 * data)
489 {
490         int result;
491         u8 d;
492         struct transaction t = {.command = ACPI_EC_COMMAND_QUERY,
493                                 .wdata = NULL, .rdata = &d,
494                                 .wlen = 0, .rlen = 1};
495         if (!ec || !data)
496                 return -EINVAL;
497         /*
498          * Query the EC to find out which _Qxx method we need to evaluate.
499          * Note that successful completion of the query causes the ACPI_EC_SCI
500          * bit to be cleared (and thus clearing the interrupt source).
501          */
502         result = acpi_ec_transaction_unlocked(ec, &t);
503         if (result)
504                 return result;
505         if (!d)
506                 return -ENODATA;
507         *data = d;
508         return 0;
509 }
510
511 /* --------------------------------------------------------------------------
512                                 Event Management
513    -------------------------------------------------------------------------- */
514 int acpi_ec_add_query_handler(struct acpi_ec *ec, u8 query_bit,
515                               acpi_handle handle, acpi_ec_query_func func,
516                               void *data)
517 {
518         struct acpi_ec_query_handler *handler =
519             kzalloc(sizeof(struct acpi_ec_query_handler), GFP_KERNEL);
520         if (!handler)
521                 return -ENOMEM;
522
523         handler->query_bit = query_bit;
524         handler->handle = handle;
525         handler->func = func;
526         handler->data = data;
527         mutex_lock(&ec->lock);
528         list_add(&handler->node, &ec->list);
529         mutex_unlock(&ec->lock);
530         return 0;
531 }
532
533 EXPORT_SYMBOL_GPL(acpi_ec_add_query_handler);
534
535 void acpi_ec_remove_query_handler(struct acpi_ec *ec, u8 query_bit)
536 {
537         struct acpi_ec_query_handler *handler, *tmp;
538         mutex_lock(&ec->lock);
539         list_for_each_entry_safe(handler, tmp, &ec->list, node) {
540                 if (query_bit == handler->query_bit) {
541                         list_del(&handler->node);
542                         kfree(handler);
543                 }
544         }
545         mutex_unlock(&ec->lock);
546 }
547
548 EXPORT_SYMBOL_GPL(acpi_ec_remove_query_handler);
549
550 static void acpi_ec_run(void *cxt)
551 {
552         struct acpi_ec_query_handler *handler = cxt;
553         if (!handler)
554                 return;
555         pr_debug(PREFIX "start query execution\n");
556         if (handler->func)
557                 handler->func(handler->data);
558         else if (handler->handle)
559                 acpi_evaluate_object(handler->handle, NULL, NULL, NULL);
560         pr_debug(PREFIX "stop query execution\n");
561         kfree(handler);
562 }
563
564 static int acpi_ec_sync_query(struct acpi_ec *ec)
565 {
566         u8 value = 0;
567         int status;
568         struct acpi_ec_query_handler *handler, *copy;
569         if ((status = acpi_ec_query_unlocked(ec, &value)))
570                 return status;
571         list_for_each_entry(handler, &ec->list, node) {
572                 if (value == handler->query_bit) {
573                         /* have custom handler for this bit */
574                         copy = kmalloc(sizeof(*handler), GFP_KERNEL);
575                         if (!copy)
576                                 return -ENOMEM;
577                         memcpy(copy, handler, sizeof(*copy));
578                         pr_debug(PREFIX "push query execution (0x%2x) on queue\n", value);
579                         return acpi_os_execute((copy->func) ?
580                                 OSL_NOTIFY_HANDLER : OSL_GPE_HANDLER,
581                                 acpi_ec_run, copy);
582                 }
583         }
584         return 0;
585 }
586
587 static void acpi_ec_gpe_query(void *ec_cxt)
588 {
589         struct acpi_ec *ec = ec_cxt;
590         if (!ec)
591                 return;
592         mutex_lock(&ec->lock);
593         acpi_ec_sync_query(ec);
594         mutex_unlock(&ec->lock);
595 }
596
597 static void acpi_ec_gpe_query(void *ec_cxt);
598
599 static int ec_check_sci(struct acpi_ec *ec, u8 state)
600 {
601         if (state & ACPI_EC_FLAG_SCI) {
602                 if (!test_and_set_bit(EC_FLAGS_QUERY_PENDING, &ec->flags)) {
603                         pr_debug(PREFIX "push gpe query to the queue\n");
604                         return acpi_os_execute(OSL_NOTIFY_HANDLER,
605                                 acpi_ec_gpe_query, ec);
606                 }
607         }
608         return 0;
609 }
610
611 static u32 acpi_ec_gpe_handler(void *data)
612 {
613         struct acpi_ec *ec = data;
614
615         pr_debug(PREFIX "~~~> interrupt\n");
616
617         advance_transaction(ec, acpi_ec_read_status(ec));
618         if (ec_transaction_done(ec) &&
619             (acpi_ec_read_status(ec) & ACPI_EC_FLAG_IBF) == 0) {
620                 wake_up(&ec->wait);
621                 ec_check_sci(ec, acpi_ec_read_status(ec));
622         }
623         return ACPI_INTERRUPT_HANDLED;
624 }
625
626 /* --------------------------------------------------------------------------
627                              Address Space Management
628    -------------------------------------------------------------------------- */
629
630 static acpi_status
631 acpi_ec_space_handler(u32 function, acpi_physical_address address,
632                       u32 bits, u64 *value,
633                       void *handler_context, void *region_context)
634 {
635         struct acpi_ec *ec = handler_context;
636         int result = 0, i;
637         u8 temp = 0;
638
639         if ((address > 0xFF) || !value || !handler_context)
640                 return AE_BAD_PARAMETER;
641
642         if (function != ACPI_READ && function != ACPI_WRITE)
643                 return AE_BAD_PARAMETER;
644
645         if (bits != 8 && acpi_strict)
646                 return AE_BAD_PARAMETER;
647
648         if (EC_FLAGS_MSI)
649                 acpi_ec_burst_enable(ec);
650
651         if (function == ACPI_READ) {
652                 result = acpi_ec_read(ec, address, &temp);
653                 *value = temp;
654         } else {
655                 temp = 0xff & (*value);
656                 result = acpi_ec_write(ec, address, temp);
657         }
658
659         for (i = 8; unlikely(bits - i > 0); i += 8) {
660                 ++address;
661                 if (function == ACPI_READ) {
662                         result = acpi_ec_read(ec, address, &temp);
663                         (*value) |= ((u64)temp) << i;
664                 } else {
665                         temp = 0xff & ((*value) >> i);
666                         result = acpi_ec_write(ec, address, temp);
667                 }
668         }
669
670         if (EC_FLAGS_MSI)
671                 acpi_ec_burst_disable(ec);
672
673         switch (result) {
674         case -EINVAL:
675                 return AE_BAD_PARAMETER;
676                 break;
677         case -ENODEV:
678                 return AE_NOT_FOUND;
679                 break;
680         case -ETIME:
681                 return AE_TIME;
682                 break;
683         default:
684                 return AE_OK;
685         }
686 }
687
688 /* --------------------------------------------------------------------------
689                               FS Interface (/proc)
690    -------------------------------------------------------------------------- */
691
692 static struct proc_dir_entry *acpi_ec_dir;
693
694 static int acpi_ec_read_info(struct seq_file *seq, void *offset)
695 {
696         struct acpi_ec *ec = seq->private;
697
698         if (!ec)
699                 goto end;
700
701         seq_printf(seq, "gpe:\t\t\t0x%02x\n", (u32) ec->gpe);
702         seq_printf(seq, "ports:\t\t\t0x%02x, 0x%02x\n",
703                    (unsigned)ec->command_addr, (unsigned)ec->data_addr);
704         seq_printf(seq, "use global lock:\t%s\n",
705                    ec->global_lock ? "yes" : "no");
706       end:
707         return 0;
708 }
709
710 static int acpi_ec_info_open_fs(struct inode *inode, struct file *file)
711 {
712         return single_open(file, acpi_ec_read_info, PDE(inode)->data);
713 }
714
715 static const struct file_operations acpi_ec_info_ops = {
716         .open = acpi_ec_info_open_fs,
717         .read = seq_read,
718         .llseek = seq_lseek,
719         .release = single_release,
720         .owner = THIS_MODULE,
721 };
722
723 static int acpi_ec_add_fs(struct acpi_device *device)
724 {
725         struct proc_dir_entry *entry = NULL;
726
727         if (!acpi_device_dir(device)) {
728                 acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device),
729                                                      acpi_ec_dir);
730                 if (!acpi_device_dir(device))
731                         return -ENODEV;
732         }
733
734         entry = proc_create_data(ACPI_EC_FILE_INFO, S_IRUGO,
735                                  acpi_device_dir(device),
736                                  &acpi_ec_info_ops, acpi_driver_data(device));
737         if (!entry)
738                 return -ENODEV;
739         return 0;
740 }
741
742 static int acpi_ec_remove_fs(struct acpi_device *device)
743 {
744
745         if (acpi_device_dir(device)) {
746                 remove_proc_entry(ACPI_EC_FILE_INFO, acpi_device_dir(device));
747                 remove_proc_entry(acpi_device_bid(device), acpi_ec_dir);
748                 acpi_device_dir(device) = NULL;
749         }
750
751         return 0;
752 }
753
754 /* --------------------------------------------------------------------------
755                                Driver Interface
756    -------------------------------------------------------------------------- */
757 static acpi_status
758 ec_parse_io_ports(struct acpi_resource *resource, void *context);
759
760 static struct acpi_ec *make_acpi_ec(void)
761 {
762         struct acpi_ec *ec = kzalloc(sizeof(struct acpi_ec), GFP_KERNEL);
763         if (!ec)
764                 return NULL;
765         ec->flags = 1 << EC_FLAGS_QUERY_PENDING;
766         mutex_init(&ec->lock);
767         init_waitqueue_head(&ec->wait);
768         INIT_LIST_HEAD(&ec->list);
769         spin_lock_init(&ec->curr_lock);
770         return ec;
771 }
772
773 static acpi_status
774 acpi_ec_register_query_methods(acpi_handle handle, u32 level,
775                                void *context, void **return_value)
776 {
777         char node_name[5];
778         struct acpi_buffer buffer = { sizeof(node_name), node_name };
779         struct acpi_ec *ec = context;
780         int value = 0;
781         acpi_status status;
782
783         status = acpi_get_name(handle, ACPI_SINGLE_NAME, &buffer);
784
785         if (ACPI_SUCCESS(status) && sscanf(node_name, "_Q%x", &value) == 1) {
786                 acpi_ec_add_query_handler(ec, value, handle, NULL, NULL);
787         }
788         return AE_OK;
789 }
790
791 static acpi_status
792 ec_parse_device(acpi_handle handle, u32 Level, void *context, void **retval)
793 {
794         acpi_status status;
795         unsigned long long tmp = 0;
796
797         struct acpi_ec *ec = context;
798
799         /* clear addr values, ec_parse_io_ports depend on it */
800         ec->command_addr = ec->data_addr = 0;
801
802         status = acpi_walk_resources(handle, METHOD_NAME__CRS,
803                                      ec_parse_io_ports, ec);
804         if (ACPI_FAILURE(status))
805                 return status;
806
807         /* Get GPE bit assignment (EC events). */
808         /* TODO: Add support for _GPE returning a package */
809         status = acpi_evaluate_integer(handle, "_GPE", NULL, &tmp);
810         if (ACPI_FAILURE(status))
811                 return status;
812         ec->gpe = tmp;
813         /* Use the global lock for all EC transactions? */
814         tmp = 0;
815         acpi_evaluate_integer(handle, "_GLK", NULL, &tmp);
816         ec->global_lock = tmp;
817         ec->handle = handle;
818         return AE_CTRL_TERMINATE;
819 }
820
821 static int ec_install_handlers(struct acpi_ec *ec)
822 {
823         acpi_status status;
824         if (test_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags))
825                 return 0;
826         status = acpi_install_gpe_handler(NULL, ec->gpe,
827                                   ACPI_GPE_EDGE_TRIGGERED,
828                                   &acpi_ec_gpe_handler, ec);
829         if (ACPI_FAILURE(status))
830                 return -ENODEV;
831
832         acpi_enable_gpe(NULL, ec->gpe, ACPI_GPE_TYPE_RUNTIME);
833         status = acpi_install_address_space_handler(ec->handle,
834                                                     ACPI_ADR_SPACE_EC,
835                                                     &acpi_ec_space_handler,
836                                                     NULL, ec);
837         if (ACPI_FAILURE(status)) {
838                 if (status == AE_NOT_FOUND) {
839                         /*
840                          * Maybe OS fails in evaluating the _REG object.
841                          * The AE_NOT_FOUND error will be ignored and OS
842                          * continue to initialize EC.
843                          */
844                         printk(KERN_ERR "Fail in evaluating the _REG object"
845                                 " of EC device. Broken bios is suspected.\n");
846                 } else {
847                         acpi_remove_gpe_handler(NULL, ec->gpe,
848                                 &acpi_ec_gpe_handler);
849                         acpi_disable_gpe(NULL, ec->gpe, ACPI_GPE_TYPE_RUNTIME);
850                         return -ENODEV;
851                 }
852         }
853
854         set_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags);
855         return 0;
856 }
857
858 static void ec_remove_handlers(struct acpi_ec *ec)
859 {
860         acpi_disable_gpe(NULL, ec->gpe, ACPI_GPE_TYPE_RUNTIME);
861         if (ACPI_FAILURE(acpi_remove_address_space_handler(ec->handle,
862                                 ACPI_ADR_SPACE_EC, &acpi_ec_space_handler)))
863                 pr_err(PREFIX "failed to remove space handler\n");
864         if (ACPI_FAILURE(acpi_remove_gpe_handler(NULL, ec->gpe,
865                                 &acpi_ec_gpe_handler)))
866                 pr_err(PREFIX "failed to remove gpe handler\n");
867         clear_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags);
868 }
869
870 static int acpi_ec_add(struct acpi_device *device)
871 {
872         struct acpi_ec *ec = NULL;
873         int ret;
874
875         strcpy(acpi_device_name(device), ACPI_EC_DEVICE_NAME);
876         strcpy(acpi_device_class(device), ACPI_EC_CLASS);
877
878         /* Check for boot EC */
879         if (boot_ec &&
880             (boot_ec->handle == device->handle ||
881              boot_ec->handle == ACPI_ROOT_OBJECT)) {
882                 ec = boot_ec;
883                 boot_ec = NULL;
884         } else {
885                 ec = make_acpi_ec();
886                 if (!ec)
887                         return -ENOMEM;
888         }
889         if (ec_parse_device(device->handle, 0, ec, NULL) !=
890                 AE_CTRL_TERMINATE) {
891                         kfree(ec);
892                         return -EINVAL;
893         }
894
895         ec->handle = device->handle;
896
897         /* Find and register all query methods */
898         acpi_walk_namespace(ACPI_TYPE_METHOD, ec->handle, 1,
899                             acpi_ec_register_query_methods, NULL, ec, NULL);
900
901         if (!first_ec)
902                 first_ec = ec;
903         device->driver_data = ec;
904         acpi_ec_add_fs(device);
905         pr_info(PREFIX "GPE = 0x%lx, I/O: command/status = 0x%lx, data = 0x%lx\n",
906                           ec->gpe, ec->command_addr, ec->data_addr);
907
908         ret = ec_install_handlers(ec);
909
910         /* EC is fully operational, allow queries */
911         clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags);
912         return ret;
913 }
914
915 static int acpi_ec_remove(struct acpi_device *device, int type)
916 {
917         struct acpi_ec *ec;
918         struct acpi_ec_query_handler *handler, *tmp;
919
920         if (!device)
921                 return -EINVAL;
922
923         ec = acpi_driver_data(device);
924         ec_remove_handlers(ec);
925         mutex_lock(&ec->lock);
926         list_for_each_entry_safe(handler, tmp, &ec->list, node) {
927                 list_del(&handler->node);
928                 kfree(handler);
929         }
930         mutex_unlock(&ec->lock);
931         acpi_ec_remove_fs(device);
932         device->driver_data = NULL;
933         if (ec == first_ec)
934                 first_ec = NULL;
935         kfree(ec);
936         return 0;
937 }
938
939 static acpi_status
940 ec_parse_io_ports(struct acpi_resource *resource, void *context)
941 {
942         struct acpi_ec *ec = context;
943
944         if (resource->type != ACPI_RESOURCE_TYPE_IO)
945                 return AE_OK;
946
947         /*
948          * The first address region returned is the data port, and
949          * the second address region returned is the status/command
950          * port.
951          */
952         if (ec->data_addr == 0)
953                 ec->data_addr = resource->data.io.minimum;
954         else if (ec->command_addr == 0)
955                 ec->command_addr = resource->data.io.minimum;
956         else
957                 return AE_CTRL_TERMINATE;
958
959         return AE_OK;
960 }
961
962 int __init acpi_boot_ec_enable(void)
963 {
964         if (!boot_ec || test_bit(EC_FLAGS_HANDLERS_INSTALLED, &boot_ec->flags))
965                 return 0;
966         if (!ec_install_handlers(boot_ec)) {
967                 first_ec = boot_ec;
968                 return 0;
969         }
970         return -EFAULT;
971 }
972
973 static const struct acpi_device_id ec_device_ids[] = {
974         {"PNP0C09", 0},
975         {"", 0},
976 };
977
978 /* Some BIOS do not survive early DSDT scan, skip it */
979 static int ec_skip_dsdt_scan(const struct dmi_system_id *id)
980 {
981         EC_FLAGS_SKIP_DSDT_SCAN = 1;
982         return 0;
983 }
984
985 /* ASUStek often supplies us with broken ECDT, validate it */
986 static int ec_validate_ecdt(const struct dmi_system_id *id)
987 {
988         EC_FLAGS_VALIDATE_ECDT = 1;
989         return 0;
990 }
991
992 /* MSI EC needs special treatment, enable it */
993 static int ec_flag_msi(const struct dmi_system_id *id)
994 {
995         printk(KERN_DEBUG PREFIX "Detected MSI hardware, enabling workarounds.\n");
996         EC_FLAGS_MSI = 1;
997         EC_FLAGS_VALIDATE_ECDT = 1;
998         return 0;
999 }
1000
1001 static struct dmi_system_id __initdata ec_dmi_table[] = {
1002         {
1003         ec_skip_dsdt_scan, "Compal JFL92", {
1004         DMI_MATCH(DMI_BIOS_VENDOR, "COMPAL"),
1005         DMI_MATCH(DMI_BOARD_NAME, "JFL92") }, NULL},
1006         {
1007         ec_flag_msi, "MSI hardware", {
1008         DMI_MATCH(DMI_BIOS_VENDOR, "Micro-Star")}, NULL},
1009         {
1010         ec_flag_msi, "MSI hardware", {
1011         DMI_MATCH(DMI_SYS_VENDOR, "Micro-Star")}, NULL},
1012         {
1013         ec_flag_msi, "MSI hardware", {
1014         DMI_MATCH(DMI_CHASSIS_VENDOR, "MICRO-Star")}, NULL},
1015         {
1016         ec_validate_ecdt, "ASUS hardware", {
1017         DMI_MATCH(DMI_BIOS_VENDOR, "ASUS") }, NULL},
1018         {},
1019 };
1020
1021
1022 int __init acpi_ec_ecdt_probe(void)
1023 {
1024         acpi_status status;
1025         struct acpi_ec *saved_ec = NULL;
1026         struct acpi_table_ecdt *ecdt_ptr;
1027
1028         boot_ec = make_acpi_ec();
1029         if (!boot_ec)
1030                 return -ENOMEM;
1031         /*
1032          * Generate a boot ec context
1033          */
1034         dmi_check_system(ec_dmi_table);
1035         status = acpi_get_table(ACPI_SIG_ECDT, 1,
1036                                 (struct acpi_table_header **)&ecdt_ptr);
1037         if (ACPI_SUCCESS(status)) {
1038                 pr_info(PREFIX "EC description table is found, configuring boot EC\n");
1039                 boot_ec->command_addr = ecdt_ptr->control.address;
1040                 boot_ec->data_addr = ecdt_ptr->data.address;
1041                 boot_ec->gpe = ecdt_ptr->gpe;
1042                 boot_ec->handle = ACPI_ROOT_OBJECT;
1043                 acpi_get_handle(ACPI_ROOT_OBJECT, ecdt_ptr->id, &boot_ec->handle);
1044                 /* Don't trust ECDT, which comes from ASUSTek */
1045                 if (!EC_FLAGS_VALIDATE_ECDT)
1046                         goto install;
1047                 saved_ec = kmalloc(sizeof(struct acpi_ec), GFP_KERNEL);
1048                 if (!saved_ec)
1049                         return -ENOMEM;
1050                 memcpy(saved_ec, boot_ec, sizeof(struct acpi_ec));
1051         /* fall through */
1052         }
1053
1054         if (EC_FLAGS_SKIP_DSDT_SCAN)
1055                 return -ENODEV;
1056
1057         /* This workaround is needed only on some broken machines,
1058          * which require early EC, but fail to provide ECDT */
1059         printk(KERN_DEBUG PREFIX "Look up EC in DSDT\n");
1060         status = acpi_get_devices(ec_device_ids[0].id, ec_parse_device,
1061                                         boot_ec, NULL);
1062         /* Check that acpi_get_devices actually find something */
1063         if (ACPI_FAILURE(status) || !boot_ec->handle)
1064                 goto error;
1065         if (saved_ec) {
1066                 /* try to find good ECDT from ASUSTek */
1067                 if (saved_ec->command_addr != boot_ec->command_addr ||
1068                     saved_ec->data_addr != boot_ec->data_addr ||
1069                     saved_ec->gpe != boot_ec->gpe ||
1070                     saved_ec->handle != boot_ec->handle)
1071                         pr_info(PREFIX "ASUSTek keeps feeding us with broken "
1072                         "ECDT tables, which are very hard to workaround. "
1073                         "Trying to use DSDT EC info instead. Please send "
1074                         "output of acpidump to linux-acpi@vger.kernel.org\n");
1075                 kfree(saved_ec);
1076                 saved_ec = NULL;
1077         } else {
1078                 /* We really need to limit this workaround, the only ASUS,
1079                 * which needs it, has fake EC._INI method, so use it as flag.
1080                 * Keep boot_ec struct as it will be needed soon.
1081                 */
1082                 acpi_handle dummy;
1083                 if (!dmi_name_in_vendors("ASUS") ||
1084                     ACPI_FAILURE(acpi_get_handle(boot_ec->handle, "_INI",
1085                                                         &dummy)))
1086                         return -ENODEV;
1087         }
1088 install:
1089         if (!ec_install_handlers(boot_ec)) {
1090                 first_ec = boot_ec;
1091                 return 0;
1092         }
1093 error:
1094         kfree(boot_ec);
1095         boot_ec = NULL;
1096         return -ENODEV;
1097 }
1098
1099 static int acpi_ec_suspend(struct acpi_device *device, pm_message_t state)
1100 {
1101         struct acpi_ec *ec = acpi_driver_data(device);
1102         /* Stop using the GPE, but keep it reference counted. */
1103         acpi_set_gpe(NULL, ec->gpe, ACPI_GPE_DISABLE);
1104         return 0;
1105 }
1106
1107 static int acpi_ec_resume(struct acpi_device *device)
1108 {
1109         struct acpi_ec *ec = acpi_driver_data(device);
1110         /* Enable the GPE again, but don't reference count it once more. */
1111         acpi_set_gpe(NULL, ec->gpe, ACPI_GPE_ENABLE);
1112         return 0;
1113 }
1114
1115 static struct acpi_driver acpi_ec_driver = {
1116         .name = "ec",
1117         .class = ACPI_EC_CLASS,
1118         .ids = ec_device_ids,
1119         .ops = {
1120                 .add = acpi_ec_add,
1121                 .remove = acpi_ec_remove,
1122                 .suspend = acpi_ec_suspend,
1123                 .resume = acpi_ec_resume,
1124                 },
1125 };
1126
1127 int __init acpi_ec_init(void)
1128 {
1129         int result = 0;
1130
1131         acpi_ec_dir = proc_mkdir(ACPI_EC_CLASS, acpi_root_dir);
1132         if (!acpi_ec_dir)
1133                 return -ENODEV;
1134
1135         /* Now register the driver for the EC */
1136         result = acpi_bus_register_driver(&acpi_ec_driver);
1137         if (result < 0) {
1138                 remove_proc_entry(ACPI_EC_CLASS, acpi_root_dir);
1139                 return -ENODEV;
1140         }
1141
1142         return result;
1143 }
1144
1145 /* EC driver currently not unloadable */
1146 #if 0
1147 static void __exit acpi_ec_exit(void)
1148 {
1149
1150         acpi_bus_unregister_driver(&acpi_ec_driver);
1151
1152         remove_proc_entry(ACPI_EC_CLASS, acpi_root_dir);
1153
1154         return;
1155 }
1156 #endif  /* 0 */