ACPI: EC: Allow multibyte access to EC
[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 <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 *value64,
632                       void *handler_context, void *region_context)
633 {
634         struct acpi_ec *ec = handler_context;
635         int result = 0, i, bytes = bits / 8;
636         u8 *value = (u8 *)value64;
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 (EC_FLAGS_MSI || bits > 8)
645                 acpi_ec_burst_enable(ec);
646
647         for (i = 0; i < bytes; ++i, ++address, ++value)
648                 result = (function == ACPI_READ) ?
649                         acpi_ec_read(ec, address, value) :
650                         acpi_ec_write(ec, address, *value);
651
652         if (EC_FLAGS_MSI || bits > 8)
653                 acpi_ec_burst_disable(ec);
654
655         switch (result) {
656         case -EINVAL:
657                 return AE_BAD_PARAMETER;
658                 break;
659         case -ENODEV:
660                 return AE_NOT_FOUND;
661                 break;
662         case -ETIME:
663                 return AE_TIME;
664                 break;
665         default:
666                 return AE_OK;
667         }
668 }
669
670 /* --------------------------------------------------------------------------
671                               FS Interface (/proc)
672    -------------------------------------------------------------------------- */
673
674 static struct proc_dir_entry *acpi_ec_dir;
675
676 static int acpi_ec_read_info(struct seq_file *seq, void *offset)
677 {
678         struct acpi_ec *ec = seq->private;
679
680         if (!ec)
681                 goto end;
682
683         seq_printf(seq, "gpe:\t\t\t0x%02x\n", (u32) ec->gpe);
684         seq_printf(seq, "ports:\t\t\t0x%02x, 0x%02x\n",
685                    (unsigned)ec->command_addr, (unsigned)ec->data_addr);
686         seq_printf(seq, "use global lock:\t%s\n",
687                    ec->global_lock ? "yes" : "no");
688       end:
689         return 0;
690 }
691
692 static int acpi_ec_info_open_fs(struct inode *inode, struct file *file)
693 {
694         return single_open(file, acpi_ec_read_info, PDE(inode)->data);
695 }
696
697 static const struct file_operations acpi_ec_info_ops = {
698         .open = acpi_ec_info_open_fs,
699         .read = seq_read,
700         .llseek = seq_lseek,
701         .release = single_release,
702         .owner = THIS_MODULE,
703 };
704
705 static int acpi_ec_add_fs(struct acpi_device *device)
706 {
707         struct proc_dir_entry *entry = NULL;
708
709         if (!acpi_device_dir(device)) {
710                 acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device),
711                                                      acpi_ec_dir);
712                 if (!acpi_device_dir(device))
713                         return -ENODEV;
714         }
715
716         entry = proc_create_data(ACPI_EC_FILE_INFO, S_IRUGO,
717                                  acpi_device_dir(device),
718                                  &acpi_ec_info_ops, acpi_driver_data(device));
719         if (!entry)
720                 return -ENODEV;
721         return 0;
722 }
723
724 static int acpi_ec_remove_fs(struct acpi_device *device)
725 {
726
727         if (acpi_device_dir(device)) {
728                 remove_proc_entry(ACPI_EC_FILE_INFO, acpi_device_dir(device));
729                 remove_proc_entry(acpi_device_bid(device), acpi_ec_dir);
730                 acpi_device_dir(device) = NULL;
731         }
732
733         return 0;
734 }
735
736 /* --------------------------------------------------------------------------
737                                Driver Interface
738    -------------------------------------------------------------------------- */
739 static acpi_status
740 ec_parse_io_ports(struct acpi_resource *resource, void *context);
741
742 static struct acpi_ec *make_acpi_ec(void)
743 {
744         struct acpi_ec *ec = kzalloc(sizeof(struct acpi_ec), GFP_KERNEL);
745         if (!ec)
746                 return NULL;
747         ec->flags = 1 << EC_FLAGS_QUERY_PENDING;
748         mutex_init(&ec->lock);
749         init_waitqueue_head(&ec->wait);
750         INIT_LIST_HEAD(&ec->list);
751         spin_lock_init(&ec->curr_lock);
752         return ec;
753 }
754
755 static acpi_status
756 acpi_ec_register_query_methods(acpi_handle handle, u32 level,
757                                void *context, void **return_value)
758 {
759         char node_name[5];
760         struct acpi_buffer buffer = { sizeof(node_name), node_name };
761         struct acpi_ec *ec = context;
762         int value = 0;
763         acpi_status status;
764
765         status = acpi_get_name(handle, ACPI_SINGLE_NAME, &buffer);
766
767         if (ACPI_SUCCESS(status) && sscanf(node_name, "_Q%x", &value) == 1) {
768                 acpi_ec_add_query_handler(ec, value, handle, NULL, NULL);
769         }
770         return AE_OK;
771 }
772
773 static acpi_status
774 ec_parse_device(acpi_handle handle, u32 Level, void *context, void **retval)
775 {
776         acpi_status status;
777         unsigned long long tmp = 0;
778
779         struct acpi_ec *ec = context;
780
781         /* clear addr values, ec_parse_io_ports depend on it */
782         ec->command_addr = ec->data_addr = 0;
783
784         status = acpi_walk_resources(handle, METHOD_NAME__CRS,
785                                      ec_parse_io_ports, ec);
786         if (ACPI_FAILURE(status))
787                 return status;
788
789         /* Get GPE bit assignment (EC events). */
790         /* TODO: Add support for _GPE returning a package */
791         status = acpi_evaluate_integer(handle, "_GPE", NULL, &tmp);
792         if (ACPI_FAILURE(status))
793                 return status;
794         ec->gpe = tmp;
795         /* Use the global lock for all EC transactions? */
796         tmp = 0;
797         acpi_evaluate_integer(handle, "_GLK", NULL, &tmp);
798         ec->global_lock = tmp;
799         ec->handle = handle;
800         return AE_CTRL_TERMINATE;
801 }
802
803 static int ec_install_handlers(struct acpi_ec *ec)
804 {
805         acpi_status status;
806         if (test_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags))
807                 return 0;
808         status = acpi_install_gpe_handler(NULL, ec->gpe,
809                                   ACPI_GPE_EDGE_TRIGGERED,
810                                   &acpi_ec_gpe_handler, ec);
811         if (ACPI_FAILURE(status))
812                 return -ENODEV;
813
814         acpi_enable_gpe(NULL, ec->gpe, ACPI_GPE_TYPE_RUNTIME);
815         status = acpi_install_address_space_handler(ec->handle,
816                                                     ACPI_ADR_SPACE_EC,
817                                                     &acpi_ec_space_handler,
818                                                     NULL, ec);
819         if (ACPI_FAILURE(status)) {
820                 if (status == AE_NOT_FOUND) {
821                         /*
822                          * Maybe OS fails in evaluating the _REG object.
823                          * The AE_NOT_FOUND error will be ignored and OS
824                          * continue to initialize EC.
825                          */
826                         printk(KERN_ERR "Fail in evaluating the _REG object"
827                                 " of EC device. Broken bios is suspected.\n");
828                 } else {
829                         acpi_remove_gpe_handler(NULL, ec->gpe,
830                                 &acpi_ec_gpe_handler);
831                         acpi_disable_gpe(NULL, ec->gpe, ACPI_GPE_TYPE_RUNTIME);
832                         return -ENODEV;
833                 }
834         }
835
836         set_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags);
837         return 0;
838 }
839
840 static void ec_remove_handlers(struct acpi_ec *ec)
841 {
842         acpi_disable_gpe(NULL, ec->gpe, ACPI_GPE_TYPE_RUNTIME);
843         if (ACPI_FAILURE(acpi_remove_address_space_handler(ec->handle,
844                                 ACPI_ADR_SPACE_EC, &acpi_ec_space_handler)))
845                 pr_err(PREFIX "failed to remove space handler\n");
846         if (ACPI_FAILURE(acpi_remove_gpe_handler(NULL, ec->gpe,
847                                 &acpi_ec_gpe_handler)))
848                 pr_err(PREFIX "failed to remove gpe handler\n");
849         clear_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags);
850 }
851
852 static int acpi_ec_add(struct acpi_device *device)
853 {
854         struct acpi_ec *ec = NULL;
855         int ret;
856
857         strcpy(acpi_device_name(device), ACPI_EC_DEVICE_NAME);
858         strcpy(acpi_device_class(device), ACPI_EC_CLASS);
859
860         /* Check for boot EC */
861         if (boot_ec &&
862             (boot_ec->handle == device->handle ||
863              boot_ec->handle == ACPI_ROOT_OBJECT)) {
864                 ec = boot_ec;
865                 boot_ec = NULL;
866         } else {
867                 ec = make_acpi_ec();
868                 if (!ec)
869                         return -ENOMEM;
870         }
871         if (ec_parse_device(device->handle, 0, ec, NULL) !=
872                 AE_CTRL_TERMINATE) {
873                         kfree(ec);
874                         return -EINVAL;
875         }
876
877         ec->handle = device->handle;
878
879         /* Find and register all query methods */
880         acpi_walk_namespace(ACPI_TYPE_METHOD, ec->handle, 1,
881                             acpi_ec_register_query_methods, NULL, ec, NULL);
882
883         if (!first_ec)
884                 first_ec = ec;
885         device->driver_data = ec;
886         acpi_ec_add_fs(device);
887         pr_info(PREFIX "GPE = 0x%lx, I/O: command/status = 0x%lx, data = 0x%lx\n",
888                           ec->gpe, ec->command_addr, ec->data_addr);
889
890         ret = ec_install_handlers(ec);
891
892         /* EC is fully operational, allow queries */
893         clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags);
894         return ret;
895 }
896
897 static int acpi_ec_remove(struct acpi_device *device, int type)
898 {
899         struct acpi_ec *ec;
900         struct acpi_ec_query_handler *handler, *tmp;
901
902         if (!device)
903                 return -EINVAL;
904
905         ec = acpi_driver_data(device);
906         ec_remove_handlers(ec);
907         mutex_lock(&ec->lock);
908         list_for_each_entry_safe(handler, tmp, &ec->list, node) {
909                 list_del(&handler->node);
910                 kfree(handler);
911         }
912         mutex_unlock(&ec->lock);
913         acpi_ec_remove_fs(device);
914         device->driver_data = NULL;
915         if (ec == first_ec)
916                 first_ec = NULL;
917         kfree(ec);
918         return 0;
919 }
920
921 static acpi_status
922 ec_parse_io_ports(struct acpi_resource *resource, void *context)
923 {
924         struct acpi_ec *ec = context;
925
926         if (resource->type != ACPI_RESOURCE_TYPE_IO)
927                 return AE_OK;
928
929         /*
930          * The first address region returned is the data port, and
931          * the second address region returned is the status/command
932          * port.
933          */
934         if (ec->data_addr == 0)
935                 ec->data_addr = resource->data.io.minimum;
936         else if (ec->command_addr == 0)
937                 ec->command_addr = resource->data.io.minimum;
938         else
939                 return AE_CTRL_TERMINATE;
940
941         return AE_OK;
942 }
943
944 int __init acpi_boot_ec_enable(void)
945 {
946         if (!boot_ec || test_bit(EC_FLAGS_HANDLERS_INSTALLED, &boot_ec->flags))
947                 return 0;
948         if (!ec_install_handlers(boot_ec)) {
949                 first_ec = boot_ec;
950                 return 0;
951         }
952         return -EFAULT;
953 }
954
955 static const struct acpi_device_id ec_device_ids[] = {
956         {"PNP0C09", 0},
957         {"", 0},
958 };
959
960 /* Some BIOS do not survive early DSDT scan, skip it */
961 static int ec_skip_dsdt_scan(const struct dmi_system_id *id)
962 {
963         EC_FLAGS_SKIP_DSDT_SCAN = 1;
964         return 0;
965 }
966
967 /* ASUStek often supplies us with broken ECDT, validate it */
968 static int ec_validate_ecdt(const struct dmi_system_id *id)
969 {
970         EC_FLAGS_VALIDATE_ECDT = 1;
971         return 0;
972 }
973
974 /* MSI EC needs special treatment, enable it */
975 static int ec_flag_msi(const struct dmi_system_id *id)
976 {
977         printk(KERN_DEBUG PREFIX "Detected MSI hardware, enabling workarounds.\n");
978         EC_FLAGS_MSI = 1;
979         EC_FLAGS_VALIDATE_ECDT = 1;
980         return 0;
981 }
982
983 static struct dmi_system_id __initdata ec_dmi_table[] = {
984         {
985         ec_skip_dsdt_scan, "Compal JFL92", {
986         DMI_MATCH(DMI_BIOS_VENDOR, "COMPAL"),
987         DMI_MATCH(DMI_BOARD_NAME, "JFL92") }, NULL},
988         {
989         ec_flag_msi, "MSI hardware", {
990         DMI_MATCH(DMI_BIOS_VENDOR, "Micro-Star")}, NULL},
991         {
992         ec_flag_msi, "MSI hardware", {
993         DMI_MATCH(DMI_SYS_VENDOR, "Micro-Star")}, NULL},
994         {
995         ec_flag_msi, "MSI hardware", {
996         DMI_MATCH(DMI_CHASSIS_VENDOR, "MICRO-Star")}, NULL},
997         {
998         ec_validate_ecdt, "ASUS hardware", {
999         DMI_MATCH(DMI_BIOS_VENDOR, "ASUS") }, NULL},
1000         {},
1001 };
1002
1003
1004 int __init acpi_ec_ecdt_probe(void)
1005 {
1006         acpi_status status;
1007         struct acpi_ec *saved_ec = NULL;
1008         struct acpi_table_ecdt *ecdt_ptr;
1009
1010         boot_ec = make_acpi_ec();
1011         if (!boot_ec)
1012                 return -ENOMEM;
1013         /*
1014          * Generate a boot ec context
1015          */
1016         dmi_check_system(ec_dmi_table);
1017         status = acpi_get_table(ACPI_SIG_ECDT, 1,
1018                                 (struct acpi_table_header **)&ecdt_ptr);
1019         if (ACPI_SUCCESS(status)) {
1020                 pr_info(PREFIX "EC description table is found, configuring boot EC\n");
1021                 boot_ec->command_addr = ecdt_ptr->control.address;
1022                 boot_ec->data_addr = ecdt_ptr->data.address;
1023                 boot_ec->gpe = ecdt_ptr->gpe;
1024                 boot_ec->handle = ACPI_ROOT_OBJECT;
1025                 acpi_get_handle(ACPI_ROOT_OBJECT, ecdt_ptr->id, &boot_ec->handle);
1026                 /* Don't trust ECDT, which comes from ASUSTek */
1027                 if (!EC_FLAGS_VALIDATE_ECDT)
1028                         goto install;
1029                 saved_ec = kmalloc(sizeof(struct acpi_ec), GFP_KERNEL);
1030                 if (!saved_ec)
1031                         return -ENOMEM;
1032                 memcpy(saved_ec, boot_ec, sizeof(struct acpi_ec));
1033         /* fall through */
1034         }
1035
1036         if (EC_FLAGS_SKIP_DSDT_SCAN)
1037                 return -ENODEV;
1038
1039         /* This workaround is needed only on some broken machines,
1040          * which require early EC, but fail to provide ECDT */
1041         printk(KERN_DEBUG PREFIX "Look up EC in DSDT\n");
1042         status = acpi_get_devices(ec_device_ids[0].id, ec_parse_device,
1043                                         boot_ec, NULL);
1044         /* Check that acpi_get_devices actually find something */
1045         if (ACPI_FAILURE(status) || !boot_ec->handle)
1046                 goto error;
1047         if (saved_ec) {
1048                 /* try to find good ECDT from ASUSTek */
1049                 if (saved_ec->command_addr != boot_ec->command_addr ||
1050                     saved_ec->data_addr != boot_ec->data_addr ||
1051                     saved_ec->gpe != boot_ec->gpe ||
1052                     saved_ec->handle != boot_ec->handle)
1053                         pr_info(PREFIX "ASUSTek keeps feeding us with broken "
1054                         "ECDT tables, which are very hard to workaround. "
1055                         "Trying to use DSDT EC info instead. Please send "
1056                         "output of acpidump to linux-acpi@vger.kernel.org\n");
1057                 kfree(saved_ec);
1058                 saved_ec = NULL;
1059         } else {
1060                 /* We really need to limit this workaround, the only ASUS,
1061                 * which needs it, has fake EC._INI method, so use it as flag.
1062                 * Keep boot_ec struct as it will be needed soon.
1063                 */
1064                 acpi_handle dummy;
1065                 if (!dmi_name_in_vendors("ASUS") ||
1066                     ACPI_FAILURE(acpi_get_handle(boot_ec->handle, "_INI",
1067                                                         &dummy)))
1068                         return -ENODEV;
1069         }
1070 install:
1071         if (!ec_install_handlers(boot_ec)) {
1072                 first_ec = boot_ec;
1073                 return 0;
1074         }
1075 error:
1076         kfree(boot_ec);
1077         boot_ec = NULL;
1078         return -ENODEV;
1079 }
1080
1081 static int acpi_ec_suspend(struct acpi_device *device, pm_message_t state)
1082 {
1083         struct acpi_ec *ec = acpi_driver_data(device);
1084         /* Stop using the GPE, but keep it reference counted. */
1085         acpi_set_gpe(NULL, ec->gpe, ACPI_GPE_DISABLE);
1086         return 0;
1087 }
1088
1089 static int acpi_ec_resume(struct acpi_device *device)
1090 {
1091         struct acpi_ec *ec = acpi_driver_data(device);
1092         /* Enable the GPE again, but don't reference count it once more. */
1093         acpi_set_gpe(NULL, ec->gpe, ACPI_GPE_ENABLE);
1094         return 0;
1095 }
1096
1097 static struct acpi_driver acpi_ec_driver = {
1098         .name = "ec",
1099         .class = ACPI_EC_CLASS,
1100         .ids = ec_device_ids,
1101         .ops = {
1102                 .add = acpi_ec_add,
1103                 .remove = acpi_ec_remove,
1104                 .suspend = acpi_ec_suspend,
1105                 .resume = acpi_ec_resume,
1106                 },
1107 };
1108
1109 int __init acpi_ec_init(void)
1110 {
1111         int result = 0;
1112
1113         acpi_ec_dir = proc_mkdir(ACPI_EC_CLASS, acpi_root_dir);
1114         if (!acpi_ec_dir)
1115                 return -ENODEV;
1116
1117         /* Now register the driver for the EC */
1118         result = acpi_bus_register_driver(&acpi_ec_driver);
1119         if (result < 0) {
1120                 remove_proc_entry(ACPI_EC_CLASS, acpi_root_dir);
1121                 return -ENODEV;
1122         }
1123
1124         return result;
1125 }
1126
1127 /* EC driver currently not unloadable */
1128 #if 0
1129 static void __exit acpi_ec_exit(void)
1130 {
1131
1132         acpi_bus_unregister_driver(&acpi_ec_driver);
1133
1134         remove_proc_entry(ACPI_EC_CLASS, acpi_root_dir);
1135
1136         return;
1137 }
1138 #endif  /* 0 */