Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc-2.6
[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/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 <asm/io.h>
43 #include <acpi/acpi_bus.h>
44 #include <acpi/acpi_drivers.h>
45 #include <linux/dmi.h>
46
47 #define ACPI_EC_CLASS                   "embedded_controller"
48 #define ACPI_EC_DEVICE_NAME             "Embedded Controller"
49 #define ACPI_EC_FILE_INFO               "info"
50
51 #define PREFIX                          "ACPI: EC: "
52
53 /* EC status register */
54 #define ACPI_EC_FLAG_OBF        0x01    /* Output buffer full */
55 #define ACPI_EC_FLAG_IBF        0x02    /* Input buffer full */
56 #define ACPI_EC_FLAG_BURST      0x10    /* burst mode */
57 #define ACPI_EC_FLAG_SCI        0x20    /* EC-SCI occurred */
58
59 /* EC commands */
60 enum ec_command {
61         ACPI_EC_COMMAND_READ = 0x80,
62         ACPI_EC_COMMAND_WRITE = 0x81,
63         ACPI_EC_BURST_ENABLE = 0x82,
64         ACPI_EC_BURST_DISABLE = 0x83,
65         ACPI_EC_COMMAND_QUERY = 0x84,
66 };
67
68 #define ACPI_EC_DELAY           500     /* Wait 500ms max. during EC ops */
69 #define ACPI_EC_UDELAY_GLK      1000    /* Wait 1ms max. to get global lock */
70 #define ACPI_EC_CDELAY          10      /* Wait 10us before polling EC */
71 #define ACPI_EC_MSI_UDELAY      550     /* Wait 550us for MSI EC */
72
73 #define ACPI_EC_STORM_THRESHOLD 8       /* number of false interrupts
74                                            per one transaction */
75
76 enum {
77         EC_FLAGS_QUERY_PENDING,         /* Query is pending */
78         EC_FLAGS_GPE_STORM,             /* GPE storm detected */
79         EC_FLAGS_HANDLERS_INSTALLED,    /* Handlers for GPE and
80                                          * OpReg are installed */
81         EC_FLAGS_FROZEN,                /* Transactions are suspended */
82 };
83
84 /* If we find an EC via the ECDT, we need to keep a ptr to its context */
85 /* External interfaces use first EC only, so remember */
86 typedef int (*acpi_ec_query_func) (void *data);
87
88 struct acpi_ec_query_handler {
89         struct list_head node;
90         acpi_ec_query_func func;
91         acpi_handle handle;
92         void *data;
93         u8 query_bit;
94 };
95
96 struct transaction {
97         const u8 *wdata;
98         u8 *rdata;
99         unsigned short irq_count;
100         u8 command;
101         u8 wi;
102         u8 ri;
103         u8 wlen;
104         u8 rlen;
105         bool done;
106 };
107
108 static struct acpi_ec {
109         acpi_handle handle;
110         unsigned long gpe;
111         unsigned long command_addr;
112         unsigned long data_addr;
113         unsigned long global_lock;
114         unsigned long flags;
115         struct mutex lock;
116         wait_queue_head_t wait;
117         struct list_head list;
118         struct transaction *curr;
119         spinlock_t curr_lock;
120 } *boot_ec, *first_ec;
121
122 static int EC_FLAGS_MSI; /* Out-of-spec MSI controller */
123 static int EC_FLAGS_VALIDATE_ECDT; /* ASUStec ECDTs need to be validated */
124 static int EC_FLAGS_SKIP_DSDT_SCAN; /* Not all BIOS survive early DSDT scan */
125
126 /* --------------------------------------------------------------------------
127                              Transaction Management
128    -------------------------------------------------------------------------- */
129
130 static inline u8 acpi_ec_read_status(struct acpi_ec *ec)
131 {
132         u8 x = inb(ec->command_addr);
133         pr_debug(PREFIX "---> status = 0x%2.2x\n", x);
134         return x;
135 }
136
137 static inline u8 acpi_ec_read_data(struct acpi_ec *ec)
138 {
139         u8 x = inb(ec->data_addr);
140         pr_debug(PREFIX "---> data = 0x%2.2x\n", x);
141         return x;
142 }
143
144 static inline void acpi_ec_write_cmd(struct acpi_ec *ec, u8 command)
145 {
146         pr_debug(PREFIX "<--- command = 0x%2.2x\n", command);
147         outb(command, ec->command_addr);
148 }
149
150 static inline void acpi_ec_write_data(struct acpi_ec *ec, u8 data)
151 {
152         pr_debug(PREFIX "<--- data = 0x%2.2x\n", data);
153         outb(data, ec->data_addr);
154 }
155
156 static int ec_transaction_done(struct acpi_ec *ec)
157 {
158         unsigned long flags;
159         int ret = 0;
160         spin_lock_irqsave(&ec->curr_lock, flags);
161         if (!ec->curr || ec->curr->done)
162                 ret = 1;
163         spin_unlock_irqrestore(&ec->curr_lock, flags);
164         return ret;
165 }
166
167 static void start_transaction(struct acpi_ec *ec)
168 {
169         ec->curr->irq_count = ec->curr->wi = ec->curr->ri = 0;
170         ec->curr->done = false;
171         acpi_ec_write_cmd(ec, ec->curr->command);
172 }
173
174 static void advance_transaction(struct acpi_ec *ec, u8 status)
175 {
176         unsigned long flags;
177         spin_lock_irqsave(&ec->curr_lock, flags);
178         if (!ec->curr)
179                 goto unlock;
180         if (ec->curr->wlen > ec->curr->wi) {
181                 if ((status & ACPI_EC_FLAG_IBF) == 0)
182                         acpi_ec_write_data(ec,
183                                 ec->curr->wdata[ec->curr->wi++]);
184                 else
185                         goto err;
186         } else if (ec->curr->rlen > ec->curr->ri) {
187                 if ((status & ACPI_EC_FLAG_OBF) == 1) {
188                         ec->curr->rdata[ec->curr->ri++] = acpi_ec_read_data(ec);
189                         if (ec->curr->rlen == ec->curr->ri)
190                                 ec->curr->done = true;
191                 } else
192                         goto err;
193         } else if (ec->curr->wlen == ec->curr->wi &&
194                    (status & ACPI_EC_FLAG_IBF) == 0)
195                 ec->curr->done = true;
196         goto unlock;
197 err:
198         /* false interrupt, state didn't change */
199         if (in_interrupt())
200                 ++ec->curr->irq_count;
201 unlock:
202         spin_unlock_irqrestore(&ec->curr_lock, flags);
203 }
204
205 static int acpi_ec_sync_query(struct acpi_ec *ec);
206
207 static int ec_check_sci_sync(struct acpi_ec *ec, u8 state)
208 {
209         if (state & ACPI_EC_FLAG_SCI) {
210                 if (!test_and_set_bit(EC_FLAGS_QUERY_PENDING, &ec->flags))
211                         return acpi_ec_sync_query(ec);
212         }
213         return 0;
214 }
215
216 static int ec_poll(struct acpi_ec *ec)
217 {
218         unsigned long flags;
219         int repeat = 2; /* number of command restarts */
220         while (repeat--) {
221                 unsigned long delay = jiffies +
222                         msecs_to_jiffies(ACPI_EC_DELAY);
223                 do {
224                         /* don't sleep with disabled interrupts */
225                         if (EC_FLAGS_MSI || irqs_disabled()) {
226                                 udelay(ACPI_EC_MSI_UDELAY);
227                                 if (ec_transaction_done(ec))
228                                         return 0;
229                         } else {
230                                 if (wait_event_timeout(ec->wait,
231                                                 ec_transaction_done(ec),
232                                                 msecs_to_jiffies(1)))
233                                         return 0;
234                         }
235                         advance_transaction(ec, acpi_ec_read_status(ec));
236                 } while (time_before(jiffies, delay));
237                 if (acpi_ec_read_status(ec) & ACPI_EC_FLAG_IBF)
238                         break;
239                 pr_debug(PREFIX "controller reset, restart transaction\n");
240                 spin_lock_irqsave(&ec->curr_lock, flags);
241                 start_transaction(ec);
242                 spin_unlock_irqrestore(&ec->curr_lock, flags);
243         }
244         return -ETIME;
245 }
246
247 static int acpi_ec_transaction_unlocked(struct acpi_ec *ec,
248                                         struct transaction *t)
249 {
250         unsigned long tmp;
251         int ret = 0;
252         if (EC_FLAGS_MSI)
253                 udelay(ACPI_EC_MSI_UDELAY);
254         /* start transaction */
255         spin_lock_irqsave(&ec->curr_lock, tmp);
256         /* following two actions should be kept atomic */
257         ec->curr = t;
258         start_transaction(ec);
259         if (ec->curr->command == ACPI_EC_COMMAND_QUERY)
260                 clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags);
261         spin_unlock_irqrestore(&ec->curr_lock, tmp);
262         ret = ec_poll(ec);
263         spin_lock_irqsave(&ec->curr_lock, tmp);
264         ec->curr = NULL;
265         spin_unlock_irqrestore(&ec->curr_lock, tmp);
266         return ret;
267 }
268
269 static int ec_check_ibf0(struct acpi_ec *ec)
270 {
271         u8 status = acpi_ec_read_status(ec);
272         return (status & ACPI_EC_FLAG_IBF) == 0;
273 }
274
275 static int ec_wait_ibf0(struct acpi_ec *ec)
276 {
277         unsigned long delay = jiffies + msecs_to_jiffies(ACPI_EC_DELAY);
278         /* interrupt wait manually if GPE mode is not active */
279         while (time_before(jiffies, delay))
280                 if (wait_event_timeout(ec->wait, ec_check_ibf0(ec),
281                                         msecs_to_jiffies(1)))
282                         return 0;
283         return -ETIME;
284 }
285
286 static int acpi_ec_transaction(struct acpi_ec *ec, struct transaction *t)
287 {
288         int status;
289         u32 glk;
290         if (!ec || (!t) || (t->wlen && !t->wdata) || (t->rlen && !t->rdata))
291                 return -EINVAL;
292         if (t->rdata)
293                 memset(t->rdata, 0, t->rlen);
294         mutex_lock(&ec->lock);
295         if (test_bit(EC_FLAGS_FROZEN, &ec->flags)) {
296                 status = -EINVAL;
297                 goto unlock;
298         }
299         if (ec->global_lock) {
300                 status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk);
301                 if (ACPI_FAILURE(status)) {
302                         status = -ENODEV;
303                         goto unlock;
304                 }
305         }
306         if (ec_wait_ibf0(ec)) {
307                 pr_err(PREFIX "input buffer is not empty, "
308                                 "aborting transaction\n");
309                 status = -ETIME;
310                 goto end;
311         }
312         pr_debug(PREFIX "transaction start\n");
313         /* disable GPE during transaction if storm is detected */
314         if (test_bit(EC_FLAGS_GPE_STORM, &ec->flags)) {
315                 /*
316                  * It has to be disabled at the hardware level regardless of the
317                  * GPE reference counting, so that it doesn't trigger.
318                  */
319                 acpi_set_gpe(NULL, ec->gpe, ACPI_GPE_DISABLE);
320         }
321
322         status = acpi_ec_transaction_unlocked(ec, t);
323
324         /* check if we received SCI during transaction */
325         ec_check_sci_sync(ec, acpi_ec_read_status(ec));
326         if (test_bit(EC_FLAGS_GPE_STORM, &ec->flags)) {
327                 msleep(1);
328                 /*
329                  * It is safe to enable the GPE outside of the transaction.  Use
330                  * acpi_set_gpe() for that, since we used it to disable the GPE
331                  * above.
332                  */
333                 acpi_set_gpe(NULL, ec->gpe, ACPI_GPE_ENABLE);
334         } else if (t->irq_count > ACPI_EC_STORM_THRESHOLD) {
335                 pr_info(PREFIX "GPE storm detected, "
336                         "transactions will use polling mode\n");
337                 set_bit(EC_FLAGS_GPE_STORM, &ec->flags);
338         }
339         pr_debug(PREFIX "transaction end\n");
340 end:
341         if (ec->global_lock)
342                 acpi_release_global_lock(glk);
343 unlock:
344         mutex_unlock(&ec->lock);
345         return status;
346 }
347
348 static int acpi_ec_burst_enable(struct acpi_ec *ec)
349 {
350         u8 d;
351         struct transaction t = {.command = ACPI_EC_BURST_ENABLE,
352                                 .wdata = NULL, .rdata = &d,
353                                 .wlen = 0, .rlen = 1};
354
355         return acpi_ec_transaction(ec, &t);
356 }
357
358 static int acpi_ec_burst_disable(struct acpi_ec *ec)
359 {
360         struct transaction t = {.command = ACPI_EC_BURST_DISABLE,
361                                 .wdata = NULL, .rdata = NULL,
362                                 .wlen = 0, .rlen = 0};
363
364         return (acpi_ec_read_status(ec) & ACPI_EC_FLAG_BURST) ?
365                                 acpi_ec_transaction(ec, &t) : 0;
366 }
367
368 static int acpi_ec_read(struct acpi_ec *ec, u8 address, u8 * data)
369 {
370         int result;
371         u8 d;
372         struct transaction t = {.command = ACPI_EC_COMMAND_READ,
373                                 .wdata = &address, .rdata = &d,
374                                 .wlen = 1, .rlen = 1};
375
376         result = acpi_ec_transaction(ec, &t);
377         *data = d;
378         return result;
379 }
380
381 static int acpi_ec_write(struct acpi_ec *ec, u8 address, u8 data)
382 {
383         u8 wdata[2] = { address, data };
384         struct transaction t = {.command = ACPI_EC_COMMAND_WRITE,
385                                 .wdata = wdata, .rdata = NULL,
386                                 .wlen = 2, .rlen = 0};
387
388         return acpi_ec_transaction(ec, &t);
389 }
390
391 /*
392  * Externally callable EC access functions. For now, assume 1 EC only
393  */
394 int ec_burst_enable(void)
395 {
396         if (!first_ec)
397                 return -ENODEV;
398         return acpi_ec_burst_enable(first_ec);
399 }
400
401 EXPORT_SYMBOL(ec_burst_enable);
402
403 int ec_burst_disable(void)
404 {
405         if (!first_ec)
406                 return -ENODEV;
407         return acpi_ec_burst_disable(first_ec);
408 }
409
410 EXPORT_SYMBOL(ec_burst_disable);
411
412 int ec_read(u8 addr, u8 * val)
413 {
414         int err;
415         u8 temp_data;
416
417         if (!first_ec)
418                 return -ENODEV;
419
420         err = acpi_ec_read(first_ec, addr, &temp_data);
421
422         if (!err) {
423                 *val = temp_data;
424                 return 0;
425         } else
426                 return err;
427 }
428
429 EXPORT_SYMBOL(ec_read);
430
431 int ec_write(u8 addr, u8 val)
432 {
433         int err;
434
435         if (!first_ec)
436                 return -ENODEV;
437
438         err = acpi_ec_write(first_ec, addr, val);
439
440         return err;
441 }
442
443 EXPORT_SYMBOL(ec_write);
444
445 int ec_transaction(u8 command,
446                    const u8 * wdata, unsigned wdata_len,
447                    u8 * rdata, unsigned rdata_len,
448                    int force_poll)
449 {
450         struct transaction t = {.command = command,
451                                 .wdata = wdata, .rdata = rdata,
452                                 .wlen = wdata_len, .rlen = rdata_len};
453         if (!first_ec)
454                 return -ENODEV;
455
456         return acpi_ec_transaction(first_ec, &t);
457 }
458
459 EXPORT_SYMBOL(ec_transaction);
460
461 void acpi_ec_suspend_transactions(void)
462 {
463         struct acpi_ec *ec = first_ec;
464
465         if (!ec)
466                 return;
467
468         mutex_lock(&ec->lock);
469         /* Prevent transactions from being carried out */
470         set_bit(EC_FLAGS_FROZEN, &ec->flags);
471         mutex_unlock(&ec->lock);
472 }
473
474 void acpi_ec_resume_transactions(void)
475 {
476         struct acpi_ec *ec = first_ec;
477
478         if (!ec)
479                 return;
480
481         mutex_lock(&ec->lock);
482         /* Allow transactions to be carried out again */
483         clear_bit(EC_FLAGS_FROZEN, &ec->flags);
484         mutex_unlock(&ec->lock);
485 }
486
487 static int acpi_ec_query_unlocked(struct acpi_ec *ec, u8 * data)
488 {
489         int result;
490         u8 d;
491         struct transaction t = {.command = ACPI_EC_COMMAND_QUERY,
492                                 .wdata = NULL, .rdata = &d,
493                                 .wlen = 0, .rlen = 1};
494         if (!ec || !data)
495                 return -EINVAL;
496         /*
497          * Query the EC to find out which _Qxx method we need to evaluate.
498          * Note that successful completion of the query causes the ACPI_EC_SCI
499          * bit to be cleared (and thus clearing the interrupt source).
500          */
501         result = acpi_ec_transaction_unlocked(ec, &t);
502         if (result)
503                 return result;
504         if (!d)
505                 return -ENODATA;
506         *data = d;
507         return 0;
508 }
509
510 /* --------------------------------------------------------------------------
511                                 Event Management
512    -------------------------------------------------------------------------- */
513 int acpi_ec_add_query_handler(struct acpi_ec *ec, u8 query_bit,
514                               acpi_handle handle, acpi_ec_query_func func,
515                               void *data)
516 {
517         struct acpi_ec_query_handler *handler =
518             kzalloc(sizeof(struct acpi_ec_query_handler), GFP_KERNEL);
519         if (!handler)
520                 return -ENOMEM;
521
522         handler->query_bit = query_bit;
523         handler->handle = handle;
524         handler->func = func;
525         handler->data = data;
526         mutex_lock(&ec->lock);
527         list_add(&handler->node, &ec->list);
528         mutex_unlock(&ec->lock);
529         return 0;
530 }
531
532 EXPORT_SYMBOL_GPL(acpi_ec_add_query_handler);
533
534 void acpi_ec_remove_query_handler(struct acpi_ec *ec, u8 query_bit)
535 {
536         struct acpi_ec_query_handler *handler, *tmp;
537         mutex_lock(&ec->lock);
538         list_for_each_entry_safe(handler, tmp, &ec->list, node) {
539                 if (query_bit == handler->query_bit) {
540                         list_del(&handler->node);
541                         kfree(handler);
542                 }
543         }
544         mutex_unlock(&ec->lock);
545 }
546
547 EXPORT_SYMBOL_GPL(acpi_ec_remove_query_handler);
548
549 static void acpi_ec_run(void *cxt)
550 {
551         struct acpi_ec_query_handler *handler = cxt;
552         if (!handler)
553                 return;
554         pr_debug(PREFIX "start query execution\n");
555         if (handler->func)
556                 handler->func(handler->data);
557         else if (handler->handle)
558                 acpi_evaluate_object(handler->handle, NULL, NULL, NULL);
559         pr_debug(PREFIX "stop query execution\n");
560         kfree(handler);
561 }
562
563 static int acpi_ec_sync_query(struct acpi_ec *ec)
564 {
565         u8 value = 0;
566         int status;
567         struct acpi_ec_query_handler *handler, *copy;
568         if ((status = acpi_ec_query_unlocked(ec, &value)))
569                 return status;
570         list_for_each_entry(handler, &ec->list, node) {
571                 if (value == handler->query_bit) {
572                         /* have custom handler for this bit */
573                         copy = kmalloc(sizeof(*handler), GFP_KERNEL);
574                         if (!copy)
575                                 return -ENOMEM;
576                         memcpy(copy, handler, sizeof(*copy));
577                         pr_debug(PREFIX "push query execution (0x%2x) on queue\n", value);
578                         return acpi_os_execute((copy->func) ?
579                                 OSL_NOTIFY_HANDLER : OSL_GPE_HANDLER,
580                                 acpi_ec_run, copy);
581                 }
582         }
583         return 0;
584 }
585
586 static void acpi_ec_gpe_query(void *ec_cxt)
587 {
588         struct acpi_ec *ec = ec_cxt;
589         if (!ec)
590                 return;
591         mutex_lock(&ec->lock);
592         acpi_ec_sync_query(ec);
593         mutex_unlock(&ec->lock);
594 }
595
596 static void acpi_ec_gpe_query(void *ec_cxt);
597
598 static int ec_check_sci(struct acpi_ec *ec, u8 state)
599 {
600         if (state & ACPI_EC_FLAG_SCI) {
601                 if (!test_and_set_bit(EC_FLAGS_QUERY_PENDING, &ec->flags)) {
602                         pr_debug(PREFIX "push gpe query to the queue\n");
603                         return acpi_os_execute(OSL_NOTIFY_HANDLER,
604                                 acpi_ec_gpe_query, ec);
605                 }
606         }
607         return 0;
608 }
609
610 static u32 acpi_ec_gpe_handler(void *data)
611 {
612         struct acpi_ec *ec = data;
613
614         pr_debug(PREFIX "~~~> interrupt\n");
615
616         advance_transaction(ec, acpi_ec_read_status(ec));
617         if (ec_transaction_done(ec) &&
618             (acpi_ec_read_status(ec) & ACPI_EC_FLAG_IBF) == 0) {
619                 wake_up(&ec->wait);
620                 ec_check_sci(ec, acpi_ec_read_status(ec));
621         }
622         return ACPI_INTERRUPT_HANDLED;
623 }
624
625 /* --------------------------------------------------------------------------
626                              Address Space Management
627    -------------------------------------------------------------------------- */
628
629 static acpi_status
630 acpi_ec_space_handler(u32 function, acpi_physical_address address,
631                       u32 bits, u64 *value,
632                       void *handler_context, void *region_context)
633 {
634         struct acpi_ec *ec = handler_context;
635         int result = 0, i;
636         u8 temp = 0;
637
638         if ((address > 0xFF) || !value || !handler_context)
639                 return AE_BAD_PARAMETER;
640
641         if (function != ACPI_READ && function != ACPI_WRITE)
642                 return AE_BAD_PARAMETER;
643
644         if (bits != 8 && acpi_strict)
645                 return AE_BAD_PARAMETER;
646
647         if (EC_FLAGS_MSI)
648                 acpi_ec_burst_enable(ec);
649
650         if (function == ACPI_READ) {
651                 result = acpi_ec_read(ec, address, &temp);
652                 *value = temp;
653         } else {
654                 temp = 0xff & (*value);
655                 result = acpi_ec_write(ec, address, temp);
656         }
657
658         for (i = 8; unlikely(bits - i > 0); i += 8) {
659                 ++address;
660                 if (function == ACPI_READ) {
661                         result = acpi_ec_read(ec, address, &temp);
662                         (*value) |= ((u64)temp) << i;
663                 } else {
664                         temp = 0xff & ((*value) >> i);
665                         result = acpi_ec_write(ec, address, temp);
666                 }
667         }
668
669         if (EC_FLAGS_MSI)
670                 acpi_ec_burst_disable(ec);
671
672         switch (result) {
673         case -EINVAL:
674                 return AE_BAD_PARAMETER;
675                 break;
676         case -ENODEV:
677                 return AE_NOT_FOUND;
678                 break;
679         case -ETIME:
680                 return AE_TIME;
681                 break;
682         default:
683                 return AE_OK;
684         }
685 }
686
687 /* --------------------------------------------------------------------------
688                               FS Interface (/proc)
689    -------------------------------------------------------------------------- */
690
691 static struct proc_dir_entry *acpi_ec_dir;
692
693 static int acpi_ec_read_info(struct seq_file *seq, void *offset)
694 {
695         struct acpi_ec *ec = seq->private;
696
697         if (!ec)
698                 goto end;
699
700         seq_printf(seq, "gpe:\t\t\t0x%02x\n", (u32) ec->gpe);
701         seq_printf(seq, "ports:\t\t\t0x%02x, 0x%02x\n",
702                    (unsigned)ec->command_addr, (unsigned)ec->data_addr);
703         seq_printf(seq, "use global lock:\t%s\n",
704                    ec->global_lock ? "yes" : "no");
705       end:
706         return 0;
707 }
708
709 static int acpi_ec_info_open_fs(struct inode *inode, struct file *file)
710 {
711         return single_open(file, acpi_ec_read_info, PDE(inode)->data);
712 }
713
714 static const struct file_operations acpi_ec_info_ops = {
715         .open = acpi_ec_info_open_fs,
716         .read = seq_read,
717         .llseek = seq_lseek,
718         .release = single_release,
719         .owner = THIS_MODULE,
720 };
721
722 static int acpi_ec_add_fs(struct acpi_device *device)
723 {
724         struct proc_dir_entry *entry = NULL;
725
726         if (!acpi_device_dir(device)) {
727                 acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device),
728                                                      acpi_ec_dir);
729                 if (!acpi_device_dir(device))
730                         return -ENODEV;
731         }
732
733         entry = proc_create_data(ACPI_EC_FILE_INFO, S_IRUGO,
734                                  acpi_device_dir(device),
735                                  &acpi_ec_info_ops, acpi_driver_data(device));
736         if (!entry)
737                 return -ENODEV;
738         return 0;
739 }
740
741 static int acpi_ec_remove_fs(struct acpi_device *device)
742 {
743
744         if (acpi_device_dir(device)) {
745                 remove_proc_entry(ACPI_EC_FILE_INFO, acpi_device_dir(device));
746                 remove_proc_entry(acpi_device_bid(device), acpi_ec_dir);
747                 acpi_device_dir(device) = NULL;
748         }
749
750         return 0;
751 }
752
753 /* --------------------------------------------------------------------------
754                                Driver Interface
755    -------------------------------------------------------------------------- */
756 static acpi_status
757 ec_parse_io_ports(struct acpi_resource *resource, void *context);
758
759 static struct acpi_ec *make_acpi_ec(void)
760 {
761         struct acpi_ec *ec = kzalloc(sizeof(struct acpi_ec), GFP_KERNEL);
762         if (!ec)
763                 return NULL;
764         ec->flags = 1 << EC_FLAGS_QUERY_PENDING;
765         mutex_init(&ec->lock);
766         init_waitqueue_head(&ec->wait);
767         INIT_LIST_HEAD(&ec->list);
768         spin_lock_init(&ec->curr_lock);
769         return ec;
770 }
771
772 static acpi_status
773 acpi_ec_register_query_methods(acpi_handle handle, u32 level,
774                                void *context, void **return_value)
775 {
776         char node_name[5];
777         struct acpi_buffer buffer = { sizeof(node_name), node_name };
778         struct acpi_ec *ec = context;
779         int value = 0;
780         acpi_status status;
781
782         status = acpi_get_name(handle, ACPI_SINGLE_NAME, &buffer);
783
784         if (ACPI_SUCCESS(status) && sscanf(node_name, "_Q%x", &value) == 1) {
785                 acpi_ec_add_query_handler(ec, value, handle, NULL, NULL);
786         }
787         return AE_OK;
788 }
789
790 static acpi_status
791 ec_parse_device(acpi_handle handle, u32 Level, void *context, void **retval)
792 {
793         acpi_status status;
794         unsigned long long tmp = 0;
795
796         struct acpi_ec *ec = context;
797
798         /* clear addr values, ec_parse_io_ports depend on it */
799         ec->command_addr = ec->data_addr = 0;
800
801         status = acpi_walk_resources(handle, METHOD_NAME__CRS,
802                                      ec_parse_io_ports, ec);
803         if (ACPI_FAILURE(status))
804                 return status;
805
806         /* Get GPE bit assignment (EC events). */
807         /* TODO: Add support for _GPE returning a package */
808         status = acpi_evaluate_integer(handle, "_GPE", NULL, &tmp);
809         if (ACPI_FAILURE(status))
810                 return status;
811         ec->gpe = tmp;
812         /* Use the global lock for all EC transactions? */
813         tmp = 0;
814         acpi_evaluate_integer(handle, "_GLK", NULL, &tmp);
815         ec->global_lock = tmp;
816         ec->handle = handle;
817         return AE_CTRL_TERMINATE;
818 }
819
820 static int ec_install_handlers(struct acpi_ec *ec)
821 {
822         acpi_status status;
823         if (test_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags))
824                 return 0;
825         status = acpi_install_gpe_handler(NULL, ec->gpe,
826                                   ACPI_GPE_EDGE_TRIGGERED,
827                                   &acpi_ec_gpe_handler, ec);
828         if (ACPI_FAILURE(status))
829                 return -ENODEV;
830
831         acpi_enable_gpe(NULL, ec->gpe, ACPI_GPE_TYPE_RUNTIME);
832         status = acpi_install_address_space_handler(ec->handle,
833                                                     ACPI_ADR_SPACE_EC,
834                                                     &acpi_ec_space_handler,
835                                                     NULL, ec);
836         if (ACPI_FAILURE(status)) {
837                 if (status == AE_NOT_FOUND) {
838                         /*
839                          * Maybe OS fails in evaluating the _REG object.
840                          * The AE_NOT_FOUND error will be ignored and OS
841                          * continue to initialize EC.
842                          */
843                         printk(KERN_ERR "Fail in evaluating the _REG object"
844                                 " of EC device. Broken bios is suspected.\n");
845                 } else {
846                         acpi_remove_gpe_handler(NULL, ec->gpe,
847                                 &acpi_ec_gpe_handler);
848                         acpi_disable_gpe(NULL, ec->gpe, ACPI_GPE_TYPE_RUNTIME);
849                         return -ENODEV;
850                 }
851         }
852
853         set_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags);
854         return 0;
855 }
856
857 static void ec_remove_handlers(struct acpi_ec *ec)
858 {
859         acpi_disable_gpe(NULL, ec->gpe, ACPI_GPE_TYPE_RUNTIME);
860         if (ACPI_FAILURE(acpi_remove_address_space_handler(ec->handle,
861                                 ACPI_ADR_SPACE_EC, &acpi_ec_space_handler)))
862                 pr_err(PREFIX "failed to remove space handler\n");
863         if (ACPI_FAILURE(acpi_remove_gpe_handler(NULL, ec->gpe,
864                                 &acpi_ec_gpe_handler)))
865                 pr_err(PREFIX "failed to remove gpe handler\n");
866         clear_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags);
867 }
868
869 static int acpi_ec_add(struct acpi_device *device)
870 {
871         struct acpi_ec *ec = NULL;
872         int ret;
873
874         strcpy(acpi_device_name(device), ACPI_EC_DEVICE_NAME);
875         strcpy(acpi_device_class(device), ACPI_EC_CLASS);
876
877         /* Check for boot EC */
878         if (boot_ec &&
879             (boot_ec->handle == device->handle ||
880              boot_ec->handle == ACPI_ROOT_OBJECT)) {
881                 ec = boot_ec;
882                 boot_ec = NULL;
883         } else {
884                 ec = make_acpi_ec();
885                 if (!ec)
886                         return -ENOMEM;
887         }
888         if (ec_parse_device(device->handle, 0, ec, NULL) !=
889                 AE_CTRL_TERMINATE) {
890                         kfree(ec);
891                         return -EINVAL;
892         }
893
894         ec->handle = device->handle;
895
896         /* Find and register all query methods */
897         acpi_walk_namespace(ACPI_TYPE_METHOD, ec->handle, 1,
898                             acpi_ec_register_query_methods, NULL, ec, NULL);
899
900         if (!first_ec)
901                 first_ec = ec;
902         device->driver_data = ec;
903         acpi_ec_add_fs(device);
904         pr_info(PREFIX "GPE = 0x%lx, I/O: command/status = 0x%lx, data = 0x%lx\n",
905                           ec->gpe, ec->command_addr, ec->data_addr);
906
907         ret = ec_install_handlers(ec);
908
909         /* EC is fully operational, allow queries */
910         clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags);
911         return ret;
912 }
913
914 static int acpi_ec_remove(struct acpi_device *device, int type)
915 {
916         struct acpi_ec *ec;
917         struct acpi_ec_query_handler *handler, *tmp;
918
919         if (!device)
920                 return -EINVAL;
921
922         ec = acpi_driver_data(device);
923         ec_remove_handlers(ec);
924         mutex_lock(&ec->lock);
925         list_for_each_entry_safe(handler, tmp, &ec->list, node) {
926                 list_del(&handler->node);
927                 kfree(handler);
928         }
929         mutex_unlock(&ec->lock);
930         acpi_ec_remove_fs(device);
931         device->driver_data = NULL;
932         if (ec == first_ec)
933                 first_ec = NULL;
934         kfree(ec);
935         return 0;
936 }
937
938 static acpi_status
939 ec_parse_io_ports(struct acpi_resource *resource, void *context)
940 {
941         struct acpi_ec *ec = context;
942
943         if (resource->type != ACPI_RESOURCE_TYPE_IO)
944                 return AE_OK;
945
946         /*
947          * The first address region returned is the data port, and
948          * the second address region returned is the status/command
949          * port.
950          */
951         if (ec->data_addr == 0)
952                 ec->data_addr = resource->data.io.minimum;
953         else if (ec->command_addr == 0)
954                 ec->command_addr = resource->data.io.minimum;
955         else
956                 return AE_CTRL_TERMINATE;
957
958         return AE_OK;
959 }
960
961 int __init acpi_boot_ec_enable(void)
962 {
963         if (!boot_ec || test_bit(EC_FLAGS_HANDLERS_INSTALLED, &boot_ec->flags))
964                 return 0;
965         if (!ec_install_handlers(boot_ec)) {
966                 first_ec = boot_ec;
967                 return 0;
968         }
969         return -EFAULT;
970 }
971
972 static const struct acpi_device_id ec_device_ids[] = {
973         {"PNP0C09", 0},
974         {"", 0},
975 };
976
977 /* Some BIOS do not survive early DSDT scan, skip it */
978 static int ec_skip_dsdt_scan(const struct dmi_system_id *id)
979 {
980         EC_FLAGS_SKIP_DSDT_SCAN = 1;
981         return 0;
982 }
983
984 /* ASUStek often supplies us with broken ECDT, validate it */
985 static int ec_validate_ecdt(const struct dmi_system_id *id)
986 {
987         EC_FLAGS_VALIDATE_ECDT = 1;
988         return 0;
989 }
990
991 /* MSI EC needs special treatment, enable it */
992 static int ec_flag_msi(const struct dmi_system_id *id)
993 {
994         printk(KERN_DEBUG PREFIX "Detected MSI hardware, enabling workarounds.\n");
995         EC_FLAGS_MSI = 1;
996         EC_FLAGS_VALIDATE_ECDT = 1;
997         return 0;
998 }
999
1000 static struct dmi_system_id __initdata ec_dmi_table[] = {
1001         {
1002         ec_skip_dsdt_scan, "Compal JFL92", {
1003         DMI_MATCH(DMI_BIOS_VENDOR, "COMPAL"),
1004         DMI_MATCH(DMI_BOARD_NAME, "JFL92") }, NULL},
1005         {
1006         ec_flag_msi, "MSI hardware", {
1007         DMI_MATCH(DMI_BIOS_VENDOR, "Micro-Star")}, NULL},
1008         {
1009         ec_flag_msi, "MSI hardware", {
1010         DMI_MATCH(DMI_SYS_VENDOR, "Micro-Star")}, NULL},
1011         {
1012         ec_flag_msi, "MSI hardware", {
1013         DMI_MATCH(DMI_CHASSIS_VENDOR, "MICRO-Star")}, NULL},
1014         {
1015         ec_validate_ecdt, "ASUS hardware", {
1016         DMI_MATCH(DMI_BIOS_VENDOR, "ASUS") }, NULL},
1017         {},
1018 };
1019
1020
1021 int __init acpi_ec_ecdt_probe(void)
1022 {
1023         acpi_status status;
1024         struct acpi_ec *saved_ec = NULL;
1025         struct acpi_table_ecdt *ecdt_ptr;
1026
1027         boot_ec = make_acpi_ec();
1028         if (!boot_ec)
1029                 return -ENOMEM;
1030         /*
1031          * Generate a boot ec context
1032          */
1033         dmi_check_system(ec_dmi_table);
1034         status = acpi_get_table(ACPI_SIG_ECDT, 1,
1035                                 (struct acpi_table_header **)&ecdt_ptr);
1036         if (ACPI_SUCCESS(status)) {
1037                 pr_info(PREFIX "EC description table is found, configuring boot EC\n");
1038                 boot_ec->command_addr = ecdt_ptr->control.address;
1039                 boot_ec->data_addr = ecdt_ptr->data.address;
1040                 boot_ec->gpe = ecdt_ptr->gpe;
1041                 boot_ec->handle = ACPI_ROOT_OBJECT;
1042                 acpi_get_handle(ACPI_ROOT_OBJECT, ecdt_ptr->id, &boot_ec->handle);
1043                 /* Don't trust ECDT, which comes from ASUSTek */
1044                 if (!EC_FLAGS_VALIDATE_ECDT)
1045                         goto install;
1046                 saved_ec = kmalloc(sizeof(struct acpi_ec), GFP_KERNEL);
1047                 if (!saved_ec)
1048                         return -ENOMEM;
1049                 memcpy(saved_ec, boot_ec, sizeof(struct acpi_ec));
1050         /* fall through */
1051         }
1052
1053         if (EC_FLAGS_SKIP_DSDT_SCAN)
1054                 return -ENODEV;
1055
1056         /* This workaround is needed only on some broken machines,
1057          * which require early EC, but fail to provide ECDT */
1058         printk(KERN_DEBUG PREFIX "Look up EC in DSDT\n");
1059         status = acpi_get_devices(ec_device_ids[0].id, ec_parse_device,
1060                                         boot_ec, NULL);
1061         /* Check that acpi_get_devices actually find something */
1062         if (ACPI_FAILURE(status) || !boot_ec->handle)
1063                 goto error;
1064         if (saved_ec) {
1065                 /* try to find good ECDT from ASUSTek */
1066                 if (saved_ec->command_addr != boot_ec->command_addr ||
1067                     saved_ec->data_addr != boot_ec->data_addr ||
1068                     saved_ec->gpe != boot_ec->gpe ||
1069                     saved_ec->handle != boot_ec->handle)
1070                         pr_info(PREFIX "ASUSTek keeps feeding us with broken "
1071                         "ECDT tables, which are very hard to workaround. "
1072                         "Trying to use DSDT EC info instead. Please send "
1073                         "output of acpidump to linux-acpi@vger.kernel.org\n");
1074                 kfree(saved_ec);
1075                 saved_ec = NULL;
1076         } else {
1077                 /* We really need to limit this workaround, the only ASUS,
1078                 * which needs it, has fake EC._INI method, so use it as flag.
1079                 * Keep boot_ec struct as it will be needed soon.
1080                 */
1081                 acpi_handle dummy;
1082                 if (!dmi_name_in_vendors("ASUS") ||
1083                     ACPI_FAILURE(acpi_get_handle(boot_ec->handle, "_INI",
1084                                                         &dummy)))
1085                         return -ENODEV;
1086         }
1087 install:
1088         if (!ec_install_handlers(boot_ec)) {
1089                 first_ec = boot_ec;
1090                 return 0;
1091         }
1092 error:
1093         kfree(boot_ec);
1094         boot_ec = NULL;
1095         return -ENODEV;
1096 }
1097
1098 static int acpi_ec_suspend(struct acpi_device *device, pm_message_t state)
1099 {
1100         struct acpi_ec *ec = acpi_driver_data(device);
1101         /* Stop using the GPE, but keep it reference counted. */
1102         acpi_set_gpe(NULL, ec->gpe, ACPI_GPE_DISABLE);
1103         return 0;
1104 }
1105
1106 static int acpi_ec_resume(struct acpi_device *device)
1107 {
1108         struct acpi_ec *ec = acpi_driver_data(device);
1109         /* Enable the GPE again, but don't reference count it once more. */
1110         acpi_set_gpe(NULL, ec->gpe, ACPI_GPE_ENABLE);
1111         return 0;
1112 }
1113
1114 static struct acpi_driver acpi_ec_driver = {
1115         .name = "ec",
1116         .class = ACPI_EC_CLASS,
1117         .ids = ec_device_ids,
1118         .ops = {
1119                 .add = acpi_ec_add,
1120                 .remove = acpi_ec_remove,
1121                 .suspend = acpi_ec_suspend,
1122                 .resume = acpi_ec_resume,
1123                 },
1124 };
1125
1126 int __init acpi_ec_init(void)
1127 {
1128         int result = 0;
1129
1130         acpi_ec_dir = proc_mkdir(ACPI_EC_CLASS, acpi_root_dir);
1131         if (!acpi_ec_dir)
1132                 return -ENODEV;
1133
1134         /* Now register the driver for the EC */
1135         result = acpi_bus_register_driver(&acpi_ec_driver);
1136         if (result < 0) {
1137                 remove_proc_entry(ACPI_EC_CLASS, acpi_root_dir);
1138                 return -ENODEV;
1139         }
1140
1141         return result;
1142 }
1143
1144 /* EC driver currently not unloadable */
1145 #if 0
1146 static void __exit acpi_ec_exit(void)
1147 {
1148
1149         acpi_bus_unregister_driver(&acpi_ec_driver);
1150
1151         remove_proc_entry(ACPI_EC_CLASS, acpi_root_dir);
1152
1153         return;
1154 }
1155 #endif  /* 0 */