]> nv-tegra.nvidia Code Review - linux-2.6.git/blob - drivers/acpi/ec.c
Merge branches 'bugzilla-14446', 'bugzilla-14753' and 'bugzilla-14824' into release
[linux-2.6.git] / drivers / acpi / ec.c
1 /*
2  *  ec.c - ACPI Embedded Controller Driver (v2.1)
3  *
4  *  Copyright (C) 2006-2008 Alexey Starikovskiy <astarikovskiy@suse.de>
5  *  Copyright (C) 2006 Denis Sadykov <denis.m.sadykov@intel.com>
6  *  Copyright (C) 2004 Luming Yu <luming.yu@intel.com>
7  *  Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
8  *  Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
9  *
10  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
11  *
12  *  This program is free software; you can redistribute it and/or modify
13  *  it under the terms of the GNU General Public License as published by
14  *  the Free Software Foundation; either version 2 of the License, or (at
15  *  your option) any later version.
16  *
17  *  This program is distributed in the hope that it will be useful, but
18  *  WITHOUT ANY WARRANTY; without even the implied warranty of
19  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
20  *  General Public License for more details.
21  *
22  *  You should have received a copy of the GNU General Public License along
23  *  with this program; if not, write to the Free Software Foundation, Inc.,
24  *  59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
25  *
26  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
27  */
28
29 /* Uncomment next line to get verbose printout */
30 /* #define DEBUG */
31
32 #include <linux/kernel.h>
33 #include <linux/module.h>
34 #include <linux/init.h>
35 #include <linux/types.h>
36 #include <linux/delay.h>
37 #include <linux/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 void acpi_ec_gpe_query(void *ec_cxt);
205
206 static int ec_check_sci(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_os_execute(OSL_EC_BURST_HANDLER,
211                                 acpi_ec_gpe_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         pr_debug(PREFIX "transaction start\n");
253         /* disable GPE during transaction if storm is detected */
254         if (test_bit(EC_FLAGS_GPE_STORM, &ec->flags)) {
255                 acpi_disable_gpe(NULL, ec->gpe);
256         }
257         if (EC_FLAGS_MSI)
258                 udelay(ACPI_EC_MSI_UDELAY);
259         /* start transaction */
260         spin_lock_irqsave(&ec->curr_lock, tmp);
261         /* following two actions should be kept atomic */
262         ec->curr = t;
263         start_transaction(ec);
264         if (ec->curr->command == ACPI_EC_COMMAND_QUERY)
265                 clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags);
266         spin_unlock_irqrestore(&ec->curr_lock, tmp);
267         ret = ec_poll(ec);
268         pr_debug(PREFIX "transaction end\n");
269         spin_lock_irqsave(&ec->curr_lock, tmp);
270         ec->curr = NULL;
271         spin_unlock_irqrestore(&ec->curr_lock, tmp);
272         if (test_bit(EC_FLAGS_GPE_STORM, &ec->flags)) {
273                 /* check if we received SCI during transaction */
274                 ec_check_sci(ec, acpi_ec_read_status(ec));
275                 /* it is safe to enable GPE outside of transaction */
276                 acpi_enable_gpe(NULL, ec->gpe);
277         } else if (t->irq_count > ACPI_EC_STORM_THRESHOLD) {
278                 pr_info(PREFIX "GPE storm detected, "
279                         "transactions will use polling mode\n");
280                 set_bit(EC_FLAGS_GPE_STORM, &ec->flags);
281         }
282         return ret;
283 }
284
285 static int ec_check_ibf0(struct acpi_ec *ec)
286 {
287         u8 status = acpi_ec_read_status(ec);
288         return (status & ACPI_EC_FLAG_IBF) == 0;
289 }
290
291 static int ec_wait_ibf0(struct acpi_ec *ec)
292 {
293         unsigned long delay = jiffies + msecs_to_jiffies(ACPI_EC_DELAY);
294         /* interrupt wait manually if GPE mode is not active */
295         while (time_before(jiffies, delay))
296                 if (wait_event_timeout(ec->wait, ec_check_ibf0(ec),
297                                         msecs_to_jiffies(1)))
298                         return 0;
299         return -ETIME;
300 }
301
302 static int acpi_ec_transaction(struct acpi_ec *ec, struct transaction *t)
303 {
304         int status;
305         u32 glk;
306         if (!ec || (!t) || (t->wlen && !t->wdata) || (t->rlen && !t->rdata))
307                 return -EINVAL;
308         if (t->rdata)
309                 memset(t->rdata, 0, t->rlen);
310         mutex_lock(&ec->lock);
311         if (ec->global_lock) {
312                 status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk);
313                 if (ACPI_FAILURE(status)) {
314                         status = -ENODEV;
315                         goto unlock;
316                 }
317         }
318         if (ec_wait_ibf0(ec)) {
319                 pr_err(PREFIX "input buffer is not empty, "
320                                 "aborting transaction\n");
321                 status = -ETIME;
322                 goto end;
323         }
324         status = acpi_ec_transaction_unlocked(ec, t);
325 end:
326         if (ec->global_lock)
327                 acpi_release_global_lock(glk);
328 unlock:
329         mutex_unlock(&ec->lock);
330         return status;
331 }
332
333 static int acpi_ec_burst_enable(struct acpi_ec *ec)
334 {
335         u8 d;
336         struct transaction t = {.command = ACPI_EC_BURST_ENABLE,
337                                 .wdata = NULL, .rdata = &d,
338                                 .wlen = 0, .rlen = 1};
339
340         return acpi_ec_transaction(ec, &t);
341 }
342
343 static int acpi_ec_burst_disable(struct acpi_ec *ec)
344 {
345         struct transaction t = {.command = ACPI_EC_BURST_DISABLE,
346                                 .wdata = NULL, .rdata = NULL,
347                                 .wlen = 0, .rlen = 0};
348
349         return (acpi_ec_read_status(ec) & ACPI_EC_FLAG_BURST) ?
350                                 acpi_ec_transaction(ec, &t) : 0;
351 }
352
353 static int acpi_ec_read(struct acpi_ec *ec, u8 address, u8 * data)
354 {
355         int result;
356         u8 d;
357         struct transaction t = {.command = ACPI_EC_COMMAND_READ,
358                                 .wdata = &address, .rdata = &d,
359                                 .wlen = 1, .rlen = 1};
360
361         result = acpi_ec_transaction(ec, &t);
362         *data = d;
363         return result;
364 }
365
366 static int acpi_ec_write(struct acpi_ec *ec, u8 address, u8 data)
367 {
368         u8 wdata[2] = { address, data };
369         struct transaction t = {.command = ACPI_EC_COMMAND_WRITE,
370                                 .wdata = wdata, .rdata = NULL,
371                                 .wlen = 2, .rlen = 0};
372
373         return acpi_ec_transaction(ec, &t);
374 }
375
376 /*
377  * Externally callable EC access functions. For now, assume 1 EC only
378  */
379 int ec_burst_enable(void)
380 {
381         if (!first_ec)
382                 return -ENODEV;
383         return acpi_ec_burst_enable(first_ec);
384 }
385
386 EXPORT_SYMBOL(ec_burst_enable);
387
388 int ec_burst_disable(void)
389 {
390         if (!first_ec)
391                 return -ENODEV;
392         return acpi_ec_burst_disable(first_ec);
393 }
394
395 EXPORT_SYMBOL(ec_burst_disable);
396
397 int ec_read(u8 addr, u8 * val)
398 {
399         int err;
400         u8 temp_data;
401
402         if (!first_ec)
403                 return -ENODEV;
404
405         err = acpi_ec_read(first_ec, addr, &temp_data);
406
407         if (!err) {
408                 *val = temp_data;
409                 return 0;
410         } else
411                 return err;
412 }
413
414 EXPORT_SYMBOL(ec_read);
415
416 int ec_write(u8 addr, u8 val)
417 {
418         int err;
419
420         if (!first_ec)
421                 return -ENODEV;
422
423         err = acpi_ec_write(first_ec, addr, val);
424
425         return err;
426 }
427
428 EXPORT_SYMBOL(ec_write);
429
430 int ec_transaction(u8 command,
431                    const u8 * wdata, unsigned wdata_len,
432                    u8 * rdata, unsigned rdata_len,
433                    int force_poll)
434 {
435         struct transaction t = {.command = command,
436                                 .wdata = wdata, .rdata = rdata,
437                                 .wlen = wdata_len, .rlen = rdata_len};
438         if (!first_ec)
439                 return -ENODEV;
440
441         return acpi_ec_transaction(first_ec, &t);
442 }
443
444 EXPORT_SYMBOL(ec_transaction);
445
446 static int acpi_ec_query(struct acpi_ec *ec, u8 * data)
447 {
448         int result;
449         u8 d;
450         struct transaction t = {.command = ACPI_EC_COMMAND_QUERY,
451                                 .wdata = NULL, .rdata = &d,
452                                 .wlen = 0, .rlen = 1};
453         if (!ec || !data)
454                 return -EINVAL;
455
456         /*
457          * Query the EC to find out which _Qxx method we need to evaluate.
458          * Note that successful completion of the query causes the ACPI_EC_SCI
459          * bit to be cleared (and thus clearing the interrupt source).
460          */
461
462         result = acpi_ec_transaction(ec, &t);
463         if (result)
464                 return result;
465
466         if (!d)
467                 return -ENODATA;
468
469         *data = d;
470         return 0;
471 }
472
473 /* --------------------------------------------------------------------------
474                                 Event Management
475    -------------------------------------------------------------------------- */
476 int acpi_ec_add_query_handler(struct acpi_ec *ec, u8 query_bit,
477                               acpi_handle handle, acpi_ec_query_func func,
478                               void *data)
479 {
480         struct acpi_ec_query_handler *handler =
481             kzalloc(sizeof(struct acpi_ec_query_handler), GFP_KERNEL);
482         if (!handler)
483                 return -ENOMEM;
484
485         handler->query_bit = query_bit;
486         handler->handle = handle;
487         handler->func = func;
488         handler->data = data;
489         mutex_lock(&ec->lock);
490         list_add(&handler->node, &ec->list);
491         mutex_unlock(&ec->lock);
492         return 0;
493 }
494
495 EXPORT_SYMBOL_GPL(acpi_ec_add_query_handler);
496
497 void acpi_ec_remove_query_handler(struct acpi_ec *ec, u8 query_bit)
498 {
499         struct acpi_ec_query_handler *handler, *tmp;
500         mutex_lock(&ec->lock);
501         list_for_each_entry_safe(handler, tmp, &ec->list, node) {
502                 if (query_bit == handler->query_bit) {
503                         list_del(&handler->node);
504                         kfree(handler);
505                 }
506         }
507         mutex_unlock(&ec->lock);
508 }
509
510 EXPORT_SYMBOL_GPL(acpi_ec_remove_query_handler);
511
512 static void acpi_ec_gpe_query(void *ec_cxt)
513 {
514         struct acpi_ec *ec = ec_cxt;
515         u8 value = 0;
516         struct acpi_ec_query_handler *handler, copy;
517
518         if (!ec || acpi_ec_query(ec, &value))
519                 return;
520         mutex_lock(&ec->lock);
521         list_for_each_entry(handler, &ec->list, node) {
522                 if (value == handler->query_bit) {
523                         /* have custom handler for this bit */
524                         memcpy(&copy, handler, sizeof(copy));
525                         mutex_unlock(&ec->lock);
526                         if (copy.func) {
527                                 copy.func(copy.data);
528                         } else if (copy.handle) {
529                                 acpi_evaluate_object(copy.handle, NULL, NULL, NULL);
530                         }
531                         return;
532                 }
533         }
534         mutex_unlock(&ec->lock);
535 }
536
537 static u32 acpi_ec_gpe_handler(void *data)
538 {
539         struct acpi_ec *ec = data;
540         u8 status;
541
542         pr_debug(PREFIX "~~~> interrupt\n");
543         status = acpi_ec_read_status(ec);
544
545         advance_transaction(ec, status);
546         if (ec_transaction_done(ec) && (status & ACPI_EC_FLAG_IBF) == 0)
547                 wake_up(&ec->wait);
548         ec_check_sci(ec, status);
549         return ACPI_INTERRUPT_HANDLED;
550 }
551
552 /* --------------------------------------------------------------------------
553                              Address Space Management
554    -------------------------------------------------------------------------- */
555
556 static acpi_status
557 acpi_ec_space_handler(u32 function, acpi_physical_address address,
558                       u32 bits, acpi_integer *value,
559                       void *handler_context, void *region_context)
560 {
561         struct acpi_ec *ec = handler_context;
562         int result = 0, i;
563         u8 temp = 0;
564
565         if ((address > 0xFF) || !value || !handler_context)
566                 return AE_BAD_PARAMETER;
567
568         if (function != ACPI_READ && function != ACPI_WRITE)
569                 return AE_BAD_PARAMETER;
570
571         if (bits != 8 && acpi_strict)
572                 return AE_BAD_PARAMETER;
573
574         if (EC_FLAGS_MSI)
575                 acpi_ec_burst_enable(ec);
576
577         if (function == ACPI_READ) {
578                 result = acpi_ec_read(ec, address, &temp);
579                 *value = temp;
580         } else {
581                 temp = 0xff & (*value);
582                 result = acpi_ec_write(ec, address, temp);
583         }
584
585         for (i = 8; unlikely(bits - i > 0); i += 8) {
586                 ++address;
587                 if (function == ACPI_READ) {
588                         result = acpi_ec_read(ec, address, &temp);
589                         (*value) |= ((acpi_integer)temp) << i;
590                 } else {
591                         temp = 0xff & ((*value) >> i);
592                         result = acpi_ec_write(ec, address, temp);
593                 }
594         }
595
596         if (EC_FLAGS_MSI)
597                 acpi_ec_burst_disable(ec);
598
599         switch (result) {
600         case -EINVAL:
601                 return AE_BAD_PARAMETER;
602                 break;
603         case -ENODEV:
604                 return AE_NOT_FOUND;
605                 break;
606         case -ETIME:
607                 return AE_TIME;
608                 break;
609         default:
610                 return AE_OK;
611         }
612 }
613
614 /* --------------------------------------------------------------------------
615                               FS Interface (/proc)
616    -------------------------------------------------------------------------- */
617
618 static struct proc_dir_entry *acpi_ec_dir;
619
620 static int acpi_ec_read_info(struct seq_file *seq, void *offset)
621 {
622         struct acpi_ec *ec = seq->private;
623
624         if (!ec)
625                 goto end;
626
627         seq_printf(seq, "gpe:\t\t\t0x%02x\n", (u32) ec->gpe);
628         seq_printf(seq, "ports:\t\t\t0x%02x, 0x%02x\n",
629                    (unsigned)ec->command_addr, (unsigned)ec->data_addr);
630         seq_printf(seq, "use global lock:\t%s\n",
631                    ec->global_lock ? "yes" : "no");
632       end:
633         return 0;
634 }
635
636 static int acpi_ec_info_open_fs(struct inode *inode, struct file *file)
637 {
638         return single_open(file, acpi_ec_read_info, PDE(inode)->data);
639 }
640
641 static const struct file_operations acpi_ec_info_ops = {
642         .open = acpi_ec_info_open_fs,
643         .read = seq_read,
644         .llseek = seq_lseek,
645         .release = single_release,
646         .owner = THIS_MODULE,
647 };
648
649 static int acpi_ec_add_fs(struct acpi_device *device)
650 {
651         struct proc_dir_entry *entry = NULL;
652
653         if (!acpi_device_dir(device)) {
654                 acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device),
655                                                      acpi_ec_dir);
656                 if (!acpi_device_dir(device))
657                         return -ENODEV;
658         }
659
660         entry = proc_create_data(ACPI_EC_FILE_INFO, S_IRUGO,
661                                  acpi_device_dir(device),
662                                  &acpi_ec_info_ops, acpi_driver_data(device));
663         if (!entry)
664                 return -ENODEV;
665         return 0;
666 }
667
668 static int acpi_ec_remove_fs(struct acpi_device *device)
669 {
670
671         if (acpi_device_dir(device)) {
672                 remove_proc_entry(ACPI_EC_FILE_INFO, acpi_device_dir(device));
673                 remove_proc_entry(acpi_device_bid(device), acpi_ec_dir);
674                 acpi_device_dir(device) = NULL;
675         }
676
677         return 0;
678 }
679
680 /* --------------------------------------------------------------------------
681                                Driver Interface
682    -------------------------------------------------------------------------- */
683 static acpi_status
684 ec_parse_io_ports(struct acpi_resource *resource, void *context);
685
686 static struct acpi_ec *make_acpi_ec(void)
687 {
688         struct acpi_ec *ec = kzalloc(sizeof(struct acpi_ec), GFP_KERNEL);
689         if (!ec)
690                 return NULL;
691         ec->flags = 1 << EC_FLAGS_QUERY_PENDING;
692         mutex_init(&ec->lock);
693         init_waitqueue_head(&ec->wait);
694         INIT_LIST_HEAD(&ec->list);
695         spin_lock_init(&ec->curr_lock);
696         return ec;
697 }
698
699 static acpi_status
700 acpi_ec_register_query_methods(acpi_handle handle, u32 level,
701                                void *context, void **return_value)
702 {
703         char node_name[5];
704         struct acpi_buffer buffer = { sizeof(node_name), node_name };
705         struct acpi_ec *ec = context;
706         int value = 0;
707         acpi_status status;
708
709         status = acpi_get_name(handle, ACPI_SINGLE_NAME, &buffer);
710
711         if (ACPI_SUCCESS(status) && sscanf(node_name, "_Q%x", &value) == 1) {
712                 acpi_ec_add_query_handler(ec, value, handle, NULL, NULL);
713         }
714         return AE_OK;
715 }
716
717 static acpi_status
718 ec_parse_device(acpi_handle handle, u32 Level, void *context, void **retval)
719 {
720         acpi_status status;
721         unsigned long long tmp = 0;
722
723         struct acpi_ec *ec = context;
724
725         /* clear addr values, ec_parse_io_ports depend on it */
726         ec->command_addr = ec->data_addr = 0;
727
728         status = acpi_walk_resources(handle, METHOD_NAME__CRS,
729                                      ec_parse_io_ports, ec);
730         if (ACPI_FAILURE(status))
731                 return status;
732
733         /* Get GPE bit assignment (EC events). */
734         /* TODO: Add support for _GPE returning a package */
735         status = acpi_evaluate_integer(handle, "_GPE", NULL, &tmp);
736         if (ACPI_FAILURE(status))
737                 return status;
738         ec->gpe = tmp;
739         /* Use the global lock for all EC transactions? */
740         tmp = 0;
741         acpi_evaluate_integer(handle, "_GLK", NULL, &tmp);
742         ec->global_lock = tmp;
743         ec->handle = handle;
744         return AE_CTRL_TERMINATE;
745 }
746
747 static int ec_install_handlers(struct acpi_ec *ec)
748 {
749         acpi_status status;
750         if (test_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags))
751                 return 0;
752         status = acpi_install_gpe_handler(NULL, ec->gpe,
753                                   ACPI_GPE_EDGE_TRIGGERED,
754                                   &acpi_ec_gpe_handler, ec);
755         if (ACPI_FAILURE(status))
756                 return -ENODEV;
757         acpi_set_gpe_type(NULL, ec->gpe, ACPI_GPE_TYPE_RUNTIME);
758         acpi_enable_gpe(NULL, ec->gpe);
759         status = acpi_install_address_space_handler(ec->handle,
760                                                     ACPI_ADR_SPACE_EC,
761                                                     &acpi_ec_space_handler,
762                                                     NULL, ec);
763         if (ACPI_FAILURE(status)) {
764                 if (status == AE_NOT_FOUND) {
765                         /*
766                          * Maybe OS fails in evaluating the _REG object.
767                          * The AE_NOT_FOUND error will be ignored and OS
768                          * continue to initialize EC.
769                          */
770                         printk(KERN_ERR "Fail in evaluating the _REG object"
771                                 " of EC device. Broken bios is suspected.\n");
772                 } else {
773                         acpi_remove_gpe_handler(NULL, ec->gpe,
774                                 &acpi_ec_gpe_handler);
775                         return -ENODEV;
776                 }
777         }
778
779         set_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags);
780         return 0;
781 }
782
783 static void ec_remove_handlers(struct acpi_ec *ec)
784 {
785         if (ACPI_FAILURE(acpi_remove_address_space_handler(ec->handle,
786                                 ACPI_ADR_SPACE_EC, &acpi_ec_space_handler)))
787                 pr_err(PREFIX "failed to remove space handler\n");
788         if (ACPI_FAILURE(acpi_remove_gpe_handler(NULL, ec->gpe,
789                                 &acpi_ec_gpe_handler)))
790                 pr_err(PREFIX "failed to remove gpe handler\n");
791         clear_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags);
792 }
793
794 static int acpi_ec_add(struct acpi_device *device)
795 {
796         struct acpi_ec *ec = NULL;
797         int ret;
798
799         strcpy(acpi_device_name(device), ACPI_EC_DEVICE_NAME);
800         strcpy(acpi_device_class(device), ACPI_EC_CLASS);
801
802         /* Check for boot EC */
803         if (boot_ec &&
804             (boot_ec->handle == device->handle ||
805              boot_ec->handle == ACPI_ROOT_OBJECT)) {
806                 ec = boot_ec;
807                 boot_ec = NULL;
808         } else {
809                 ec = make_acpi_ec();
810                 if (!ec)
811                         return -ENOMEM;
812         }
813         if (ec_parse_device(device->handle, 0, ec, NULL) !=
814                 AE_CTRL_TERMINATE) {
815                         kfree(ec);
816                         return -EINVAL;
817         }
818
819         ec->handle = device->handle;
820
821         /* Find and register all query methods */
822         acpi_walk_namespace(ACPI_TYPE_METHOD, ec->handle, 1,
823                             acpi_ec_register_query_methods, NULL, ec, NULL);
824
825         if (!first_ec)
826                 first_ec = ec;
827         device->driver_data = ec;
828         acpi_ec_add_fs(device);
829         pr_info(PREFIX "GPE = 0x%lx, I/O: command/status = 0x%lx, data = 0x%lx\n",
830                           ec->gpe, ec->command_addr, ec->data_addr);
831
832         ret = ec_install_handlers(ec);
833
834         /* EC is fully operational, allow queries */
835         clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags);
836         return ret;
837 }
838
839 static int acpi_ec_remove(struct acpi_device *device, int type)
840 {
841         struct acpi_ec *ec;
842         struct acpi_ec_query_handler *handler, *tmp;
843
844         if (!device)
845                 return -EINVAL;
846
847         ec = acpi_driver_data(device);
848         ec_remove_handlers(ec);
849         mutex_lock(&ec->lock);
850         list_for_each_entry_safe(handler, tmp, &ec->list, node) {
851                 list_del(&handler->node);
852                 kfree(handler);
853         }
854         mutex_unlock(&ec->lock);
855         acpi_ec_remove_fs(device);
856         device->driver_data = NULL;
857         if (ec == first_ec)
858                 first_ec = NULL;
859         kfree(ec);
860         return 0;
861 }
862
863 static acpi_status
864 ec_parse_io_ports(struct acpi_resource *resource, void *context)
865 {
866         struct acpi_ec *ec = context;
867
868         if (resource->type != ACPI_RESOURCE_TYPE_IO)
869                 return AE_OK;
870
871         /*
872          * The first address region returned is the data port, and
873          * the second address region returned is the status/command
874          * port.
875          */
876         if (ec->data_addr == 0)
877                 ec->data_addr = resource->data.io.minimum;
878         else if (ec->command_addr == 0)
879                 ec->command_addr = resource->data.io.minimum;
880         else
881                 return AE_CTRL_TERMINATE;
882
883         return AE_OK;
884 }
885
886 int __init acpi_boot_ec_enable(void)
887 {
888         if (!boot_ec || test_bit(EC_FLAGS_HANDLERS_INSTALLED, &boot_ec->flags))
889                 return 0;
890         if (!ec_install_handlers(boot_ec)) {
891                 first_ec = boot_ec;
892                 return 0;
893         }
894         return -EFAULT;
895 }
896
897 static const struct acpi_device_id ec_device_ids[] = {
898         {"PNP0C09", 0},
899         {"", 0},
900 };
901
902 /* Some BIOS do not survive early DSDT scan, skip it */
903 static int ec_skip_dsdt_scan(const struct dmi_system_id *id)
904 {
905         EC_FLAGS_SKIP_DSDT_SCAN = 1;
906         return 0;
907 }
908
909 /* ASUStek often supplies us with broken ECDT, validate it */
910 static int ec_validate_ecdt(const struct dmi_system_id *id)
911 {
912         EC_FLAGS_VALIDATE_ECDT = 1;
913         return 0;
914 }
915
916 /* MSI EC needs special treatment, enable it */
917 static int ec_flag_msi(const struct dmi_system_id *id)
918 {
919         printk(KERN_DEBUG PREFIX "Detected MSI hardware, enabling workarounds.\n");
920         EC_FLAGS_MSI = 1;
921         EC_FLAGS_VALIDATE_ECDT = 1;
922         return 0;
923 }
924
925 static struct dmi_system_id __initdata ec_dmi_table[] = {
926         {
927         ec_skip_dsdt_scan, "Compal JFL92", {
928         DMI_MATCH(DMI_BIOS_VENDOR, "COMPAL"),
929         DMI_MATCH(DMI_BOARD_NAME, "JFL92") }, NULL},
930         {
931         ec_flag_msi, "MSI hardware", {
932         DMI_MATCH(DMI_BIOS_VENDOR, "Micro-Star")}, NULL},
933         {
934         ec_flag_msi, "MSI hardware", {
935         DMI_MATCH(DMI_SYS_VENDOR, "Micro-Star")}, NULL},
936         {
937         ec_flag_msi, "MSI hardware", {
938         DMI_MATCH(DMI_CHASSIS_VENDOR, "MICRO-Star")}, NULL},
939         {
940         ec_validate_ecdt, "ASUS hardware", {
941         DMI_MATCH(DMI_BIOS_VENDOR, "ASUS") }, NULL},
942         {},
943 };
944
945
946 int __init acpi_ec_ecdt_probe(void)
947 {
948         acpi_status status;
949         struct acpi_ec *saved_ec = NULL;
950         struct acpi_table_ecdt *ecdt_ptr;
951
952         boot_ec = make_acpi_ec();
953         if (!boot_ec)
954                 return -ENOMEM;
955         /*
956          * Generate a boot ec context
957          */
958         dmi_check_system(ec_dmi_table);
959         status = acpi_get_table(ACPI_SIG_ECDT, 1,
960                                 (struct acpi_table_header **)&ecdt_ptr);
961         if (ACPI_SUCCESS(status)) {
962                 pr_info(PREFIX "EC description table is found, configuring boot EC\n");
963                 boot_ec->command_addr = ecdt_ptr->control.address;
964                 boot_ec->data_addr = ecdt_ptr->data.address;
965                 boot_ec->gpe = ecdt_ptr->gpe;
966                 boot_ec->handle = ACPI_ROOT_OBJECT;
967                 acpi_get_handle(ACPI_ROOT_OBJECT, ecdt_ptr->id, &boot_ec->handle);
968                 /* Don't trust ECDT, which comes from ASUSTek */
969                 if (!EC_FLAGS_VALIDATE_ECDT)
970                         goto install;
971                 saved_ec = kmalloc(sizeof(struct acpi_ec), GFP_KERNEL);
972                 if (!saved_ec)
973                         return -ENOMEM;
974                 memcpy(saved_ec, boot_ec, sizeof(struct acpi_ec));
975         /* fall through */
976         }
977
978         if (EC_FLAGS_SKIP_DSDT_SCAN)
979                 return -ENODEV;
980
981         /* This workaround is needed only on some broken machines,
982          * which require early EC, but fail to provide ECDT */
983         printk(KERN_DEBUG PREFIX "Look up EC in DSDT\n");
984         status = acpi_get_devices(ec_device_ids[0].id, ec_parse_device,
985                                         boot_ec, NULL);
986         /* Check that acpi_get_devices actually find something */
987         if (ACPI_FAILURE(status) || !boot_ec->handle)
988                 goto error;
989         if (saved_ec) {
990                 /* try to find good ECDT from ASUSTek */
991                 if (saved_ec->command_addr != boot_ec->command_addr ||
992                     saved_ec->data_addr != boot_ec->data_addr ||
993                     saved_ec->gpe != boot_ec->gpe ||
994                     saved_ec->handle != boot_ec->handle)
995                         pr_info(PREFIX "ASUSTek keeps feeding us with broken "
996                         "ECDT tables, which are very hard to workaround. "
997                         "Trying to use DSDT EC info instead. Please send "
998                         "output of acpidump to linux-acpi@vger.kernel.org\n");
999                 kfree(saved_ec);
1000                 saved_ec = NULL;
1001         } else {
1002                 /* We really need to limit this workaround, the only ASUS,
1003                 * which needs it, has fake EC._INI method, so use it as flag.
1004                 * Keep boot_ec struct as it will be needed soon.
1005                 */
1006                 acpi_handle dummy;
1007                 if (!dmi_name_in_vendors("ASUS") ||
1008                     ACPI_FAILURE(acpi_get_handle(boot_ec->handle, "_INI",
1009                                                         &dummy)))
1010                         return -ENODEV;
1011         }
1012 install:
1013         if (!ec_install_handlers(boot_ec)) {
1014                 first_ec = boot_ec;
1015                 return 0;
1016         }
1017 error:
1018         kfree(boot_ec);
1019         boot_ec = NULL;
1020         return -ENODEV;
1021 }
1022
1023 static int acpi_ec_suspend(struct acpi_device *device, pm_message_t state)
1024 {
1025         struct acpi_ec *ec = acpi_driver_data(device);
1026         /* Stop using GPE */
1027         acpi_disable_gpe(NULL, ec->gpe);
1028         return 0;
1029 }
1030
1031 static int acpi_ec_resume(struct acpi_device *device)
1032 {
1033         struct acpi_ec *ec = acpi_driver_data(device);
1034         /* Enable use of GPE back */
1035         acpi_enable_gpe(NULL, ec->gpe);
1036         return 0;
1037 }
1038
1039 static struct acpi_driver acpi_ec_driver = {
1040         .name = "ec",
1041         .class = ACPI_EC_CLASS,
1042         .ids = ec_device_ids,
1043         .ops = {
1044                 .add = acpi_ec_add,
1045                 .remove = acpi_ec_remove,
1046                 .suspend = acpi_ec_suspend,
1047                 .resume = acpi_ec_resume,
1048                 },
1049 };
1050
1051 int __init acpi_ec_init(void)
1052 {
1053         int result = 0;
1054
1055         acpi_ec_dir = proc_mkdir(ACPI_EC_CLASS, acpi_root_dir);
1056         if (!acpi_ec_dir)
1057                 return -ENODEV;
1058
1059         /* Now register the driver for the EC */
1060         result = acpi_bus_register_driver(&acpi_ec_driver);
1061         if (result < 0) {
1062                 remove_proc_entry(ACPI_EC_CLASS, acpi_root_dir);
1063                 return -ENODEV;
1064         }
1065
1066         return result;
1067 }
1068
1069 /* EC driver currently not unloadable */
1070 #if 0
1071 static void __exit acpi_ec_exit(void)
1072 {
1073
1074         acpi_bus_unregister_driver(&acpi_ec_driver);
1075
1076         remove_proc_entry(ACPI_EC_CLASS, acpi_root_dir);
1077
1078         return;
1079 }
1080 #endif  /* 0 */