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