ACPI: EC: make kernel messages more useful when GPE storm is detected
[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 <acpi/actypes.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 #undef PREFIX
52 #define PREFIX                          "ACPI: EC: "
53
54 /* EC status register */
55 #define ACPI_EC_FLAG_OBF        0x01    /* Output buffer full */
56 #define ACPI_EC_FLAG_IBF        0x02    /* Input buffer full */
57 #define ACPI_EC_FLAG_BURST      0x10    /* burst mode */
58 #define ACPI_EC_FLAG_SCI        0x20    /* EC-SCI occurred */
59
60 /* EC commands */
61 enum ec_command {
62         ACPI_EC_COMMAND_READ = 0x80,
63         ACPI_EC_COMMAND_WRITE = 0x81,
64         ACPI_EC_BURST_ENABLE = 0x82,
65         ACPI_EC_BURST_DISABLE = 0x83,
66         ACPI_EC_COMMAND_QUERY = 0x84,
67 };
68
69 #define ACPI_EC_DELAY           500     /* Wait 500ms max. during EC ops */
70 #define ACPI_EC_UDELAY_GLK      1000    /* Wait 1ms max. to get global lock */
71 #define ACPI_EC_UDELAY          100     /* Wait 100us before polling EC again */
72
73 #define ACPI_EC_STORM_THRESHOLD 20      /* number of false interrupts
74                                            per one transaction */
75
76 enum {
77         EC_FLAGS_QUERY_PENDING,         /* Query is pending */
78         EC_FLAGS_GPE_MODE,              /* Expect GPE to be sent
79                                          * for status change */
80         EC_FLAGS_NO_GPE,                /* Don't use GPE mode */
81         EC_FLAGS_GPE_STORM,             /* GPE storm detected */
82         EC_FLAGS_HANDLERS_INSTALLED     /* Handlers for GPE and
83                                          * OpReg are installed */
84 };
85
86 /* If we find an EC via the ECDT, we need to keep a ptr to its context */
87 /* External interfaces use first EC only, so remember */
88 typedef int (*acpi_ec_query_func) (void *data);
89
90 struct acpi_ec_query_handler {
91         struct list_head node;
92         acpi_ec_query_func func;
93         acpi_handle handle;
94         void *data;
95         u8 query_bit;
96 };
97
98 struct transaction {
99         const u8 *wdata;
100         u8 *rdata;
101         unsigned short irq_count;
102         u8 command;
103         u8 wlen;
104         u8 rlen;
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 /* 
122  * Some Asus system have exchanged ECDT data/command IO addresses.
123  */
124 static int print_ecdt_error(const struct dmi_system_id *id)
125 {
126         printk(KERN_NOTICE PREFIX "%s detected - "
127                 "ECDT has exchanged control/data I/O address\n",
128                 id->ident);
129         return 0;
130 }
131
132 static struct dmi_system_id __cpuinitdata ec_dmi_table[] = {
133         {
134         print_ecdt_error, "Asus L4R", {
135         DMI_MATCH(DMI_BIOS_VERSION, "1008.006"),
136         DMI_MATCH(DMI_PRODUCT_NAME, "L4R"),
137         DMI_MATCH(DMI_BOARD_NAME, "L4R") }, NULL},
138         {
139         print_ecdt_error, "Asus M6R", {
140         DMI_MATCH(DMI_BIOS_VERSION, "0207"),
141         DMI_MATCH(DMI_PRODUCT_NAME, "M6R"),
142         DMI_MATCH(DMI_BOARD_NAME, "M6R") }, NULL},
143         {},
144 };
145
146 /* --------------------------------------------------------------------------
147                              Transaction Management
148    -------------------------------------------------------------------------- */
149
150 static inline u8 acpi_ec_read_status(struct acpi_ec *ec)
151 {
152         u8 x = inb(ec->command_addr);
153         pr_debug(PREFIX "---> status = 0x%2.2x\n", x);
154         return x;
155 }
156
157 static inline u8 acpi_ec_read_data(struct acpi_ec *ec)
158 {
159         u8 x = inb(ec->data_addr);
160         pr_debug(PREFIX "---> data = 0x%2.2x\n", x);
161         return x;
162 }
163
164 static inline void acpi_ec_write_cmd(struct acpi_ec *ec, u8 command)
165 {
166         pr_debug(PREFIX "<--- command = 0x%2.2x\n", command);
167         outb(command, ec->command_addr);
168 }
169
170 static inline void acpi_ec_write_data(struct acpi_ec *ec, u8 data)
171 {
172         pr_debug(PREFIX "<--- data = 0x%2.2x\n", data);
173         outb(data, ec->data_addr);
174 }
175
176 static int ec_transaction_done(struct acpi_ec *ec)
177 {
178         unsigned long flags;
179         int ret = 0;
180         spin_lock_irqsave(&ec->curr_lock, flags);
181         if (!ec->curr || (!ec->curr->wlen && !ec->curr->rlen))
182                 ret = 1;
183         spin_unlock_irqrestore(&ec->curr_lock, flags);
184         return ret;
185 }
186
187 static void gpe_transaction(struct acpi_ec *ec, u8 status)
188 {
189         unsigned long flags;
190         spin_lock_irqsave(&ec->curr_lock, flags);
191         if (!ec->curr)
192                 goto unlock;
193         if (ec->curr->wlen > 0) {
194                 if ((status & ACPI_EC_FLAG_IBF) == 0) {
195                         acpi_ec_write_data(ec, *(ec->curr->wdata++));
196                         --ec->curr->wlen;
197                 } else
198                         /* false interrupt, state didn't change */
199                         ++ec->curr->irq_count;
200
201         } else if (ec->curr->rlen > 0) {
202                 if ((status & ACPI_EC_FLAG_OBF) == 1) {
203                         *(ec->curr->rdata++) = acpi_ec_read_data(ec);
204                         --ec->curr->rlen;
205                 } else
206                         /* false interrupt, state didn't change */
207                         ++ec->curr->irq_count;
208         }
209 unlock:
210         spin_unlock_irqrestore(&ec->curr_lock, flags);
211 }
212
213 static int acpi_ec_wait(struct acpi_ec *ec)
214 {
215         if (wait_event_timeout(ec->wait, ec_transaction_done(ec),
216                                msecs_to_jiffies(ACPI_EC_DELAY)))
217                 return 0;
218         /* missing GPEs, switch back to poll mode */
219         if (printk_ratelimit())
220                 pr_info(PREFIX "missing confirmations, "
221                                 "switch off interrupt mode.\n");
222         set_bit(EC_FLAGS_NO_GPE, &ec->flags);
223         clear_bit(EC_FLAGS_GPE_MODE, &ec->flags);
224         return 1;
225 }
226
227 static void acpi_ec_gpe_query(void *ec_cxt);
228
229 static int ec_check_sci(struct acpi_ec *ec, u8 state)
230 {
231         if (state & ACPI_EC_FLAG_SCI) {
232                 if (!test_and_set_bit(EC_FLAGS_QUERY_PENDING, &ec->flags))
233                         return acpi_os_execute(OSL_EC_BURST_HANDLER,
234                                 acpi_ec_gpe_query, ec);
235         }
236         return 0;
237 }
238
239 static int ec_poll(struct acpi_ec *ec)
240 {
241         unsigned long delay = jiffies + msecs_to_jiffies(ACPI_EC_DELAY);
242         udelay(ACPI_EC_UDELAY);
243         while (time_before(jiffies, delay)) {
244                 gpe_transaction(ec, acpi_ec_read_status(ec));
245                 udelay(ACPI_EC_UDELAY);
246                 if (ec_transaction_done(ec))
247                         return 0;
248         }
249         return -ETIME;
250 }
251
252 static int acpi_ec_transaction_unlocked(struct acpi_ec *ec,
253                                         struct transaction *t,
254                                         int force_poll)
255 {
256         unsigned long tmp;
257         int ret = 0;
258         pr_debug(PREFIX "transaction start\n");
259         /* disable GPE during transaction if storm is detected */
260         if (test_bit(EC_FLAGS_GPE_STORM, &ec->flags)) {
261                 clear_bit(EC_FLAGS_GPE_MODE, &ec->flags);
262                 acpi_disable_gpe(NULL, ec->gpe, ACPI_NOT_ISR);
263         }
264         /* start transaction */
265         spin_lock_irqsave(&ec->curr_lock, tmp);
266         /* following two actions should be kept atomic */
267         t->irq_count = 0;
268         ec->curr = t;
269         acpi_ec_write_cmd(ec, ec->curr->command);
270         if (ec->curr->command == ACPI_EC_COMMAND_QUERY)
271                 clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags);
272         spin_unlock_irqrestore(&ec->curr_lock, tmp);
273         /* if we selected poll mode or failed in GPE-mode do a poll loop */
274         if (force_poll ||
275             !test_bit(EC_FLAGS_GPE_MODE, &ec->flags) ||
276             acpi_ec_wait(ec))
277                 ret = ec_poll(ec);
278         pr_debug(PREFIX "transaction end\n");
279         spin_lock_irqsave(&ec->curr_lock, tmp);
280         ec->curr = NULL;
281         spin_unlock_irqrestore(&ec->curr_lock, tmp);
282         if (test_bit(EC_FLAGS_GPE_STORM, &ec->flags)) {
283                 /* check if we received SCI during transaction */
284                 ec_check_sci(ec, acpi_ec_read_status(ec));
285                 /* it is safe to enable GPE outside of transaction */
286                 acpi_enable_gpe(NULL, ec->gpe, ACPI_NOT_ISR);
287         } else if (test_bit(EC_FLAGS_GPE_MODE, &ec->flags) &&
288                    t->irq_count > ACPI_EC_STORM_THRESHOLD) {
289                 pr_info(PREFIX "GPE storm detected, "
290                         "transactions will use polling mode\n");
291                 set_bit(EC_FLAGS_GPE_STORM, &ec->flags);
292         }
293         return ret;
294 }
295
296 static int ec_check_ibf0(struct acpi_ec *ec)
297 {
298         u8 status = acpi_ec_read_status(ec);
299         return (status & ACPI_EC_FLAG_IBF) == 0;
300 }
301
302 static int ec_wait_ibf0(struct acpi_ec *ec)
303 {
304         unsigned long delay = jiffies + msecs_to_jiffies(ACPI_EC_DELAY);
305         /* interrupt wait manually if GPE mode is not active */
306         unsigned long timeout = test_bit(EC_FLAGS_GPE_MODE, &ec->flags) ?
307                 msecs_to_jiffies(ACPI_EC_DELAY) : msecs_to_jiffies(1);
308         while (time_before(jiffies, delay))
309                 if (wait_event_timeout(ec->wait, ec_check_ibf0(ec), timeout))
310                         return 0;
311         return -ETIME;
312 }
313
314 static int acpi_ec_transaction(struct acpi_ec *ec, struct transaction *t,
315                                int force_poll)
316 {
317         int status;
318         u32 glk;
319         if (!ec || (!t) || (t->wlen && !t->wdata) || (t->rlen && !t->rdata))
320                 return -EINVAL;
321         if (t->rdata)
322                 memset(t->rdata, 0, t->rlen);
323         mutex_lock(&ec->lock);
324         if (ec->global_lock) {
325                 status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk);
326                 if (ACPI_FAILURE(status)) {
327                         status = -ENODEV;
328                         goto unlock;
329                 }
330         }
331         if (ec_wait_ibf0(ec)) {
332                 pr_err(PREFIX "input buffer is not empty, "
333                                 "aborting transaction\n");
334                 status = -ETIME;
335                 goto end;
336         }
337         status = acpi_ec_transaction_unlocked(ec, t, force_poll);
338 end:
339         if (ec->global_lock)
340                 acpi_release_global_lock(glk);
341 unlock:
342         mutex_unlock(&ec->lock);
343         return status;
344 }
345
346 /*
347  * Note: samsung nv5000 doesn't work with ec burst mode.
348  * http://bugzilla.kernel.org/show_bug.cgi?id=4980
349  */
350 int acpi_ec_burst_enable(struct acpi_ec *ec)
351 {
352         u8 d;
353         struct transaction t = {.command = ACPI_EC_BURST_ENABLE,
354                                 .wdata = NULL, .rdata = &d,
355                                 .wlen = 0, .rlen = 1};
356
357         return acpi_ec_transaction(ec, &t, 0);
358 }
359
360 int acpi_ec_burst_disable(struct acpi_ec *ec)
361 {
362         struct transaction t = {.command = ACPI_EC_BURST_DISABLE,
363                                 .wdata = NULL, .rdata = NULL,
364                                 .wlen = 0, .rlen = 0};
365
366         return (acpi_ec_read_status(ec) & ACPI_EC_FLAG_BURST) ?
367                                 acpi_ec_transaction(ec, &t, 0) : 0;
368 }
369
370 static int acpi_ec_read(struct acpi_ec *ec, u8 address, u8 * data)
371 {
372         int result;
373         u8 d;
374         struct transaction t = {.command = ACPI_EC_COMMAND_READ,
375                                 .wdata = &address, .rdata = &d,
376                                 .wlen = 1, .rlen = 1};
377
378         result = acpi_ec_transaction(ec, &t, 0);
379         *data = d;
380         return result;
381 }
382
383 static int acpi_ec_write(struct acpi_ec *ec, u8 address, u8 data)
384 {
385         u8 wdata[2] = { address, data };
386         struct transaction t = {.command = ACPI_EC_COMMAND_WRITE,
387                                 .wdata = wdata, .rdata = NULL,
388                                 .wlen = 2, .rlen = 0};
389
390         return acpi_ec_transaction(ec, &t, 0);
391 }
392
393 /*
394  * Externally callable EC access functions. For now, assume 1 EC only
395  */
396 int ec_burst_enable(void)
397 {
398         if (!first_ec)
399                 return -ENODEV;
400         return acpi_ec_burst_enable(first_ec);
401 }
402
403 EXPORT_SYMBOL(ec_burst_enable);
404
405 int ec_burst_disable(void)
406 {
407         if (!first_ec)
408                 return -ENODEV;
409         return acpi_ec_burst_disable(first_ec);
410 }
411
412 EXPORT_SYMBOL(ec_burst_disable);
413
414 int ec_read(u8 addr, u8 * val)
415 {
416         int err;
417         u8 temp_data;
418
419         if (!first_ec)
420                 return -ENODEV;
421
422         err = acpi_ec_read(first_ec, addr, &temp_data);
423
424         if (!err) {
425                 *val = temp_data;
426                 return 0;
427         } else
428                 return err;
429 }
430
431 EXPORT_SYMBOL(ec_read);
432
433 int ec_write(u8 addr, u8 val)
434 {
435         int err;
436
437         if (!first_ec)
438                 return -ENODEV;
439
440         err = acpi_ec_write(first_ec, addr, val);
441
442         return err;
443 }
444
445 EXPORT_SYMBOL(ec_write);
446
447 int ec_transaction(u8 command,
448                    const u8 * wdata, unsigned wdata_len,
449                    u8 * rdata, unsigned rdata_len,
450                    int force_poll)
451 {
452         struct transaction t = {.command = command,
453                                 .wdata = wdata, .rdata = rdata,
454                                 .wlen = wdata_len, .rlen = rdata_len};
455         if (!first_ec)
456                 return -ENODEV;
457
458         return acpi_ec_transaction(first_ec, &t, force_poll);
459 }
460
461 EXPORT_SYMBOL(ec_transaction);
462
463 static int acpi_ec_query(struct acpi_ec *ec, u8 * data)
464 {
465         int result;
466         u8 d;
467         struct transaction t = {.command = ACPI_EC_COMMAND_QUERY,
468                                 .wdata = NULL, .rdata = &d,
469                                 .wlen = 0, .rlen = 1};
470         if (!ec || !data)
471                 return -EINVAL;
472
473         /*
474          * Query the EC to find out which _Qxx method we need to evaluate.
475          * Note that successful completion of the query causes the ACPI_EC_SCI
476          * bit to be cleared (and thus clearing the interrupt source).
477          */
478
479         result = acpi_ec_transaction(ec, &t, 0);
480         if (result)
481                 return result;
482
483         if (!d)
484                 return -ENODATA;
485
486         *data = d;
487         return 0;
488 }
489
490 /* --------------------------------------------------------------------------
491                                 Event Management
492    -------------------------------------------------------------------------- */
493 int acpi_ec_add_query_handler(struct acpi_ec *ec, u8 query_bit,
494                               acpi_handle handle, acpi_ec_query_func func,
495                               void *data)
496 {
497         struct acpi_ec_query_handler *handler =
498             kzalloc(sizeof(struct acpi_ec_query_handler), GFP_KERNEL);
499         if (!handler)
500                 return -ENOMEM;
501
502         handler->query_bit = query_bit;
503         handler->handle = handle;
504         handler->func = func;
505         handler->data = data;
506         mutex_lock(&ec->lock);
507         list_add(&handler->node, &ec->list);
508         mutex_unlock(&ec->lock);
509         return 0;
510 }
511
512 EXPORT_SYMBOL_GPL(acpi_ec_add_query_handler);
513
514 void acpi_ec_remove_query_handler(struct acpi_ec *ec, u8 query_bit)
515 {
516         struct acpi_ec_query_handler *handler, *tmp;
517         mutex_lock(&ec->lock);
518         list_for_each_entry_safe(handler, tmp, &ec->list, node) {
519                 if (query_bit == handler->query_bit) {
520                         list_del(&handler->node);
521                         kfree(handler);
522                 }
523         }
524         mutex_unlock(&ec->lock);
525 }
526
527 EXPORT_SYMBOL_GPL(acpi_ec_remove_query_handler);
528
529 static void acpi_ec_gpe_query(void *ec_cxt)
530 {
531         struct acpi_ec *ec = ec_cxt;
532         u8 value = 0;
533         struct acpi_ec_query_handler *handler, copy;
534
535         if (!ec || acpi_ec_query(ec, &value))
536                 return;
537         mutex_lock(&ec->lock);
538         list_for_each_entry(handler, &ec->list, node) {
539                 if (value == handler->query_bit) {
540                         /* have custom handler for this bit */
541                         memcpy(&copy, handler, sizeof(copy));
542                         mutex_unlock(&ec->lock);
543                         if (copy.func) {
544                                 copy.func(copy.data);
545                         } else if (copy.handle) {
546                                 acpi_evaluate_object(copy.handle, NULL, NULL, NULL);
547                         }
548                         return;
549                 }
550         }
551         mutex_unlock(&ec->lock);
552 }
553
554 static u32 acpi_ec_gpe_handler(void *data)
555 {
556         struct acpi_ec *ec = data;
557         u8 status;
558
559         pr_debug(PREFIX "~~~> interrupt\n");
560         status = acpi_ec_read_status(ec);
561
562         gpe_transaction(ec, status);
563         if (ec_transaction_done(ec) && (status & ACPI_EC_FLAG_IBF) == 0)
564                 wake_up(&ec->wait);
565
566         ec_check_sci(ec, status);
567         if (!test_bit(EC_FLAGS_GPE_MODE, &ec->flags) &&
568             !test_bit(EC_FLAGS_NO_GPE, &ec->flags)) {
569                 /* this is non-query, must be confirmation */
570                 if (!test_bit(EC_FLAGS_GPE_STORM, &ec->flags)) {
571                         if (printk_ratelimit())
572                                 pr_info(PREFIX "non-query interrupt received,"
573                                         " switching to interrupt mode\n");
574                 } else {
575                         /* hush, STORM switches the mode every transaction */
576                         pr_debug(PREFIX "non-query interrupt received,"
577                                 " switching to interrupt mode\n");
578                 }
579                 set_bit(EC_FLAGS_GPE_MODE, &ec->flags);
580         }
581         return ACPI_INTERRUPT_HANDLED;
582 }
583
584 /* --------------------------------------------------------------------------
585                              Address Space Management
586    -------------------------------------------------------------------------- */
587
588 static acpi_status
589 acpi_ec_space_handler(u32 function, acpi_physical_address address,
590                       u32 bits, acpi_integer *value,
591                       void *handler_context, void *region_context)
592 {
593         struct acpi_ec *ec = handler_context;
594         int result = 0, i;
595         u8 temp = 0;
596
597         if ((address > 0xFF) || !value || !handler_context)
598                 return AE_BAD_PARAMETER;
599
600         if (function != ACPI_READ && function != ACPI_WRITE)
601                 return AE_BAD_PARAMETER;
602
603         if (bits != 8 && acpi_strict)
604                 return AE_BAD_PARAMETER;
605
606         acpi_ec_burst_enable(ec);
607
608         if (function == ACPI_READ) {
609                 result = acpi_ec_read(ec, address, &temp);
610                 *value = temp;
611         } else {
612                 temp = 0xff & (*value);
613                 result = acpi_ec_write(ec, address, temp);
614         }
615
616         for (i = 8; unlikely(bits - i > 0); i += 8) {
617                 ++address;
618                 if (function == ACPI_READ) {
619                         result = acpi_ec_read(ec, address, &temp);
620                         (*value) |= ((acpi_integer)temp) << i;
621                 } else {
622                         temp = 0xff & ((*value) >> i);
623                         result = acpi_ec_write(ec, address, temp);
624                 }
625         }
626
627         acpi_ec_burst_disable(ec);
628
629         switch (result) {
630         case -EINVAL:
631                 return AE_BAD_PARAMETER;
632                 break;
633         case -ENODEV:
634                 return AE_NOT_FOUND;
635                 break;
636         case -ETIME:
637                 return AE_TIME;
638                 break;
639         default:
640                 return AE_OK;
641         }
642 }
643
644 /* --------------------------------------------------------------------------
645                               FS Interface (/proc)
646    -------------------------------------------------------------------------- */
647
648 static struct proc_dir_entry *acpi_ec_dir;
649
650 static int acpi_ec_read_info(struct seq_file *seq, void *offset)
651 {
652         struct acpi_ec *ec = seq->private;
653
654         if (!ec)
655                 goto end;
656
657         seq_printf(seq, "gpe:\t\t\t0x%02x\n", (u32) ec->gpe);
658         seq_printf(seq, "ports:\t\t\t0x%02x, 0x%02x\n",
659                    (unsigned)ec->command_addr, (unsigned)ec->data_addr);
660         seq_printf(seq, "use global lock:\t%s\n",
661                    ec->global_lock ? "yes" : "no");
662       end:
663         return 0;
664 }
665
666 static int acpi_ec_info_open_fs(struct inode *inode, struct file *file)
667 {
668         return single_open(file, acpi_ec_read_info, PDE(inode)->data);
669 }
670
671 static struct file_operations acpi_ec_info_ops = {
672         .open = acpi_ec_info_open_fs,
673         .read = seq_read,
674         .llseek = seq_lseek,
675         .release = single_release,
676         .owner = THIS_MODULE,
677 };
678
679 static int acpi_ec_add_fs(struct acpi_device *device)
680 {
681         struct proc_dir_entry *entry = NULL;
682
683         if (!acpi_device_dir(device)) {
684                 acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device),
685                                                      acpi_ec_dir);
686                 if (!acpi_device_dir(device))
687                         return -ENODEV;
688         }
689
690         entry = proc_create_data(ACPI_EC_FILE_INFO, S_IRUGO,
691                                  acpi_device_dir(device),
692                                  &acpi_ec_info_ops, acpi_driver_data(device));
693         if (!entry)
694                 return -ENODEV;
695         return 0;
696 }
697
698 static int acpi_ec_remove_fs(struct acpi_device *device)
699 {
700
701         if (acpi_device_dir(device)) {
702                 remove_proc_entry(ACPI_EC_FILE_INFO, acpi_device_dir(device));
703                 remove_proc_entry(acpi_device_bid(device), acpi_ec_dir);
704                 acpi_device_dir(device) = NULL;
705         }
706
707         return 0;
708 }
709
710 /* --------------------------------------------------------------------------
711                                Driver Interface
712    -------------------------------------------------------------------------- */
713 static acpi_status
714 ec_parse_io_ports(struct acpi_resource *resource, void *context);
715
716 static struct acpi_ec *make_acpi_ec(void)
717 {
718         struct acpi_ec *ec = kzalloc(sizeof(struct acpi_ec), GFP_KERNEL);
719         if (!ec)
720                 return NULL;
721         ec->flags = 1 << EC_FLAGS_QUERY_PENDING;
722         mutex_init(&ec->lock);
723         init_waitqueue_head(&ec->wait);
724         INIT_LIST_HEAD(&ec->list);
725         spin_lock_init(&ec->curr_lock);
726         return ec;
727 }
728
729 static acpi_status
730 acpi_ec_register_query_methods(acpi_handle handle, u32 level,
731                                void *context, void **return_value)
732 {
733         struct acpi_namespace_node *node = handle;
734         struct acpi_ec *ec = context;
735         int value = 0;
736         if (sscanf(node->name.ascii, "_Q%x", &value) == 1) {
737                 acpi_ec_add_query_handler(ec, value, handle, NULL, NULL);
738         }
739         return AE_OK;
740 }
741
742 static acpi_status
743 ec_parse_device(acpi_handle handle, u32 Level, void *context, void **retval)
744 {
745         acpi_status status;
746         unsigned long long tmp;
747
748         struct acpi_ec *ec = context;
749         status = acpi_walk_resources(handle, METHOD_NAME__CRS,
750                                      ec_parse_io_ports, ec);
751         if (ACPI_FAILURE(status))
752                 return status;
753
754         /* Get GPE bit assignment (EC events). */
755         /* TODO: Add support for _GPE returning a package */
756         status = acpi_evaluate_integer(handle, "_GPE", NULL, &tmp);
757         if (ACPI_FAILURE(status))
758                 return status;
759         ec->gpe = tmp;
760         /* Use the global lock for all EC transactions? */
761         acpi_evaluate_integer(handle, "_GLK", NULL, &tmp);
762         ec->global_lock = tmp;
763         ec->handle = handle;
764         return AE_CTRL_TERMINATE;
765 }
766
767 static void ec_remove_handlers(struct acpi_ec *ec)
768 {
769         if (ACPI_FAILURE(acpi_remove_address_space_handler(ec->handle,
770                                 ACPI_ADR_SPACE_EC, &acpi_ec_space_handler)))
771                 pr_err(PREFIX "failed to remove space handler\n");
772         if (ACPI_FAILURE(acpi_remove_gpe_handler(NULL, ec->gpe,
773                                 &acpi_ec_gpe_handler)))
774                 pr_err(PREFIX "failed to remove gpe handler\n");
775         clear_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags);
776 }
777
778 static int acpi_ec_add(struct acpi_device *device)
779 {
780         struct acpi_ec *ec = NULL;
781
782         if (!device)
783                 return -EINVAL;
784         strcpy(acpi_device_name(device), ACPI_EC_DEVICE_NAME);
785         strcpy(acpi_device_class(device), ACPI_EC_CLASS);
786
787         /* Check for boot EC */
788         if (boot_ec &&
789             (boot_ec->handle == device->handle ||
790              boot_ec->handle == ACPI_ROOT_OBJECT)) {
791                 ec = boot_ec;
792                 boot_ec = NULL;
793         } else {
794                 ec = make_acpi_ec();
795                 if (!ec)
796                         return -ENOMEM;
797                 if (ec_parse_device(device->handle, 0, ec, NULL) !=
798                     AE_CTRL_TERMINATE) {
799                         kfree(ec);
800                         return -EINVAL;
801                 }
802         }
803
804         ec->handle = device->handle;
805
806         /* Find and register all query methods */
807         acpi_walk_namespace(ACPI_TYPE_METHOD, ec->handle, 1,
808                             acpi_ec_register_query_methods, ec, NULL);
809
810         if (!first_ec)
811                 first_ec = ec;
812         device->driver_data = ec;
813         acpi_ec_add_fs(device);
814         pr_info(PREFIX "GPE = 0x%lx, I/O: command/status = 0x%lx, data = 0x%lx\n",
815                           ec->gpe, ec->command_addr, ec->data_addr);
816         pr_info(PREFIX "driver started in %s mode\n",
817                 (test_bit(EC_FLAGS_GPE_MODE, &ec->flags))?"interrupt":"poll");
818         return 0;
819 }
820
821 static int acpi_ec_remove(struct acpi_device *device, int type)
822 {
823         struct acpi_ec *ec;
824         struct acpi_ec_query_handler *handler, *tmp;
825
826         if (!device)
827                 return -EINVAL;
828
829         ec = acpi_driver_data(device);
830         mutex_lock(&ec->lock);
831         list_for_each_entry_safe(handler, tmp, &ec->list, node) {
832                 list_del(&handler->node);
833                 kfree(handler);
834         }
835         mutex_unlock(&ec->lock);
836         acpi_ec_remove_fs(device);
837         device->driver_data = NULL;
838         if (ec == first_ec)
839                 first_ec = NULL;
840         kfree(ec);
841         return 0;
842 }
843
844 static acpi_status
845 ec_parse_io_ports(struct acpi_resource *resource, void *context)
846 {
847         struct acpi_ec *ec = context;
848
849         if (resource->type != ACPI_RESOURCE_TYPE_IO)
850                 return AE_OK;
851
852         /*
853          * The first address region returned is the data port, and
854          * the second address region returned is the status/command
855          * port.
856          */
857         if (ec->data_addr == 0)
858                 ec->data_addr = resource->data.io.minimum;
859         else if (ec->command_addr == 0)
860                 ec->command_addr = resource->data.io.minimum;
861         else
862                 return AE_CTRL_TERMINATE;
863
864         return AE_OK;
865 }
866
867 static int ec_install_handlers(struct acpi_ec *ec)
868 {
869         acpi_status status;
870         if (test_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags))
871                 return 0;
872         status = acpi_install_gpe_handler(NULL, ec->gpe,
873                                   ACPI_GPE_EDGE_TRIGGERED,
874                                   &acpi_ec_gpe_handler, ec);
875         if (ACPI_FAILURE(status))
876                 return -ENODEV;
877         acpi_set_gpe_type(NULL, ec->gpe, ACPI_GPE_TYPE_RUNTIME);
878         acpi_enable_gpe(NULL, ec->gpe, ACPI_NOT_ISR);
879         status = acpi_install_address_space_handler(ec->handle,
880                                                     ACPI_ADR_SPACE_EC,
881                                                     &acpi_ec_space_handler,
882                                                     NULL, ec);
883         if (ACPI_FAILURE(status)) {
884                 if (status == AE_NOT_FOUND) {
885                         /*
886                          * Maybe OS fails in evaluating the _REG object.
887                          * The AE_NOT_FOUND error will be ignored and OS
888                          * continue to initialize EC.
889                          */
890                         printk(KERN_ERR "Fail in evaluating the _REG object"
891                                 " of EC device. Broken bios is suspected.\n");
892                 } else {
893                         acpi_remove_gpe_handler(NULL, ec->gpe,
894                                 &acpi_ec_gpe_handler);
895                         return -ENODEV;
896                 }
897         }
898
899         set_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags);
900         return 0;
901 }
902
903 static int acpi_ec_start(struct acpi_device *device)
904 {
905         struct acpi_ec *ec;
906         int ret = 0;
907
908         if (!device)
909                 return -EINVAL;
910
911         ec = acpi_driver_data(device);
912
913         if (!ec)
914                 return -EINVAL;
915
916         ret = ec_install_handlers(ec);
917
918         /* EC is fully operational, allow queries */
919         clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags);
920         return ret;
921 }
922
923 static int acpi_ec_stop(struct acpi_device *device, int type)
924 {
925         struct acpi_ec *ec;
926         if (!device)
927                 return -EINVAL;
928         ec = acpi_driver_data(device);
929         if (!ec)
930                 return -EINVAL;
931         ec_remove_handlers(ec);
932
933         return 0;
934 }
935
936 int __init acpi_boot_ec_enable(void)
937 {
938         if (!boot_ec || test_bit(EC_FLAGS_HANDLERS_INSTALLED, &boot_ec->flags))
939                 return 0;
940         if (!ec_install_handlers(boot_ec)) {
941                 first_ec = boot_ec;
942                 return 0;
943         }
944         return -EFAULT;
945 }
946
947 static const struct acpi_device_id ec_device_ids[] = {
948         {"PNP0C09", 0},
949         {"", 0},
950 };
951
952 int __init acpi_ec_ecdt_probe(void)
953 {
954         int ret;
955         acpi_status status;
956         struct acpi_table_ecdt *ecdt_ptr;
957
958         boot_ec = make_acpi_ec();
959         if (!boot_ec)
960                 return -ENOMEM;
961         /*
962          * Generate a boot ec context
963          */
964         status = acpi_get_table(ACPI_SIG_ECDT, 1,
965                                 (struct acpi_table_header **)&ecdt_ptr);
966         if (ACPI_SUCCESS(status)) {
967                 pr_info(PREFIX "EC description table is found, configuring boot EC\n");
968                 boot_ec->command_addr = ecdt_ptr->control.address;
969                 boot_ec->data_addr = ecdt_ptr->data.address;
970                 if (dmi_check_system(ec_dmi_table)) {
971                         /*
972                          * If the board falls into ec_dmi_table, it means
973                          * that ECDT table gives the incorrect command/status
974                          * & data I/O address. Just fix it.
975                          */
976                         boot_ec->data_addr = ecdt_ptr->control.address;
977                         boot_ec->command_addr = ecdt_ptr->data.address;
978                 }
979                 boot_ec->gpe = ecdt_ptr->gpe;
980                 boot_ec->handle = ACPI_ROOT_OBJECT;
981                 acpi_get_handle(ACPI_ROOT_OBJECT, ecdt_ptr->id, &boot_ec->handle);
982         } else {
983                 /* This workaround is needed only on some broken machines,
984                  * which require early EC, but fail to provide ECDT */
985                 acpi_handle x;
986                 printk(KERN_DEBUG PREFIX "Look up EC in DSDT\n");
987                 status = acpi_get_devices(ec_device_ids[0].id, ec_parse_device,
988                                                 boot_ec, NULL);
989                 /* Check that acpi_get_devices actually find something */
990                 if (ACPI_FAILURE(status) || !boot_ec->handle)
991                         goto error;
992                 /* We really need to limit this workaround, the only ASUS,
993                  * which needs it, has fake EC._INI method, so use it as flag.
994                  * Keep boot_ec struct as it will be needed soon.
995                  */
996                 if (ACPI_FAILURE(acpi_get_handle(boot_ec->handle, "_INI", &x)))
997                         return -ENODEV;
998         }
999
1000         ret = ec_install_handlers(boot_ec);
1001         if (!ret) {
1002                 first_ec = boot_ec;
1003                 return 0;
1004         }
1005       error:
1006         kfree(boot_ec);
1007         boot_ec = NULL;
1008         return -ENODEV;
1009 }
1010
1011 static int acpi_ec_suspend(struct acpi_device *device, pm_message_t state)
1012 {
1013         struct acpi_ec *ec = acpi_driver_data(device);
1014         /* Stop using GPE */
1015         set_bit(EC_FLAGS_NO_GPE, &ec->flags);
1016         clear_bit(EC_FLAGS_GPE_MODE, &ec->flags);
1017         acpi_disable_gpe(NULL, ec->gpe, ACPI_NOT_ISR);
1018         return 0;
1019 }
1020
1021 static int acpi_ec_resume(struct acpi_device *device)
1022 {
1023         struct acpi_ec *ec = acpi_driver_data(device);
1024         /* Enable use of GPE back */
1025         clear_bit(EC_FLAGS_NO_GPE, &ec->flags);
1026         acpi_enable_gpe(NULL, ec->gpe, ACPI_NOT_ISR);
1027         return 0;
1028 }
1029
1030 static struct acpi_driver acpi_ec_driver = {
1031         .name = "ec",
1032         .class = ACPI_EC_CLASS,
1033         .ids = ec_device_ids,
1034         .ops = {
1035                 .add = acpi_ec_add,
1036                 .remove = acpi_ec_remove,
1037                 .start = acpi_ec_start,
1038                 .stop = acpi_ec_stop,
1039                 .suspend = acpi_ec_suspend,
1040                 .resume = acpi_ec_resume,
1041                 },
1042 };
1043
1044 static int __init acpi_ec_init(void)
1045 {
1046         int result = 0;
1047
1048         if (acpi_disabled)
1049                 return 0;
1050
1051         acpi_ec_dir = proc_mkdir(ACPI_EC_CLASS, acpi_root_dir);
1052         if (!acpi_ec_dir)
1053                 return -ENODEV;
1054
1055         /* Now register the driver for the EC */
1056         result = acpi_bus_register_driver(&acpi_ec_driver);
1057         if (result < 0) {
1058                 remove_proc_entry(ACPI_EC_CLASS, acpi_root_dir);
1059                 return -ENODEV;
1060         }
1061
1062         return result;
1063 }
1064
1065 subsys_initcall(acpi_ec_init);
1066
1067 /* EC driver currently not unloadable */
1068 #if 0
1069 static void __exit acpi_ec_exit(void)
1070 {
1071
1072         acpi_bus_unregister_driver(&acpi_ec_driver);
1073
1074         remove_proc_entry(ACPI_EC_CLASS, acpi_root_dir);
1075
1076         return;
1077 }
1078 #endif  /* 0 */