Merge branch 'pnp-debug' into test
[linux-2.6] / drivers / acpi / ec.c
1 /*
2  *  ec.c - ACPI Embedded Controller Driver (v2.1)
3  *
4  *  Copyright (C) 2006-2008 Alexey Starikovskiy <astarikovskiy@suse.de>
5  *  Copyright (C) 2006 Denis Sadykov <denis.m.sadykov@intel.com>
6  *  Copyright (C) 2004 Luming Yu <luming.yu@intel.com>
7  *  Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
8  *  Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
9  *
10  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
11  *
12  *  This program is free software; you can redistribute it and/or modify
13  *  it under the terms of the GNU General Public License as published by
14  *  the Free Software Foundation; either version 2 of the License, or (at
15  *  your option) any later version.
16  *
17  *  This program is distributed in the hope that it will be useful, but
18  *  WITHOUT ANY WARRANTY; without even the implied warranty of
19  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
20  *  General Public License for more details.
21  *
22  *  You should have received a copy of the GNU General Public License along
23  *  with this program; if not, write to the Free Software Foundation, Inc.,
24  *  59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
25  *
26  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
27  */
28
29 /* Uncomment next line to get verbose printout */
30 /* #define DEBUG */
31
32 #include <linux/kernel.h>
33 #include <linux/module.h>
34 #include <linux/init.h>
35 #include <linux/types.h>
36 #include <linux/delay.h>
37 #include <linux/proc_fs.h>
38 #include <linux/seq_file.h>
39 #include <linux/interrupt.h>
40 #include <linux/list.h>
41 #include <linux/spinlock.h>
42 #include <asm/io.h>
43 #include <acpi/acpi_bus.h>
44 #include <acpi/acpi_drivers.h>
45 #include <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         msleep(1);
243         while (time_before(jiffies, delay)) {
244                 gpe_transaction(ec, acpi_ec_read_status(ec));
245                 msleep(1);
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_debug(PREFIX "GPE storm detected\n");
290                 set_bit(EC_FLAGS_GPE_STORM, &ec->flags);
291         }
292         return ret;
293 }
294
295 static int ec_check_ibf0(struct acpi_ec *ec)
296 {
297         u8 status = acpi_ec_read_status(ec);
298         return (status & ACPI_EC_FLAG_IBF) == 0;
299 }
300
301 static int ec_wait_ibf0(struct acpi_ec *ec)
302 {
303         unsigned long delay = jiffies + msecs_to_jiffies(ACPI_EC_DELAY);
304         /* interrupt wait manually if GPE mode is not active */
305         unsigned long timeout = test_bit(EC_FLAGS_GPE_MODE, &ec->flags) ?
306                 msecs_to_jiffies(ACPI_EC_DELAY) : msecs_to_jiffies(1);
307         while (time_before(jiffies, delay))
308                 if (wait_event_timeout(ec->wait, ec_check_ibf0(ec), timeout))
309                         return 0;
310         return -ETIME;
311 }
312
313 static int acpi_ec_transaction(struct acpi_ec *ec, struct transaction *t,
314                                int force_poll)
315 {
316         int status;
317         u32 glk;
318         if (!ec || (!t) || (t->wlen && !t->wdata) || (t->rlen && !t->rdata))
319                 return -EINVAL;
320         if (t->rdata)
321                 memset(t->rdata, 0, t->rlen);
322         mutex_lock(&ec->lock);
323         if (ec->global_lock) {
324                 status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk);
325                 if (ACPI_FAILURE(status)) {
326                         status = -ENODEV;
327                         goto unlock;
328                 }
329         }
330         if (ec_wait_ibf0(ec)) {
331                 pr_err(PREFIX "input buffer is not empty, "
332                                 "aborting transaction\n");
333                 status = -ETIME;
334                 goto end;
335         }
336         status = acpi_ec_transaction_unlocked(ec, t, force_poll);
337 end:
338         if (ec->global_lock)
339                 acpi_release_global_lock(glk);
340 unlock:
341         mutex_unlock(&ec->lock);
342         return status;
343 }
344
345 /*
346  * Note: samsung nv5000 doesn't work with ec burst mode.
347  * http://bugzilla.kernel.org/show_bug.cgi?id=4980
348  */
349 int acpi_ec_burst_enable(struct acpi_ec *ec)
350 {
351         u8 d;
352         struct transaction t = {.command = ACPI_EC_BURST_ENABLE,
353                                 .wdata = NULL, .rdata = &d,
354                                 .wlen = 0, .rlen = 1};
355
356         return acpi_ec_transaction(ec, &t, 0);
357 }
358
359 int acpi_ec_burst_disable(struct acpi_ec *ec)
360 {
361         struct transaction t = {.command = ACPI_EC_BURST_DISABLE,
362                                 .wdata = NULL, .rdata = NULL,
363                                 .wlen = 0, .rlen = 0};
364
365         return (acpi_ec_read_status(ec) & ACPI_EC_FLAG_BURST) ?
366                                 acpi_ec_transaction(ec, &t, 0) : 0;
367 }
368
369 static int acpi_ec_read(struct acpi_ec *ec, u8 address, u8 * data)
370 {
371         int result;
372         u8 d;
373         struct transaction t = {.command = ACPI_EC_COMMAND_READ,
374                                 .wdata = &address, .rdata = &d,
375                                 .wlen = 1, .rlen = 1};
376
377         result = acpi_ec_transaction(ec, &t, 0);
378         *data = d;
379         return result;
380 }
381
382 static int acpi_ec_write(struct acpi_ec *ec, u8 address, u8 data)
383 {
384         u8 wdata[2] = { address, data };
385         struct transaction t = {.command = ACPI_EC_COMMAND_WRITE,
386                                 .wdata = wdata, .rdata = NULL,
387                                 .wlen = 2, .rlen = 0};
388
389         return acpi_ec_transaction(ec, &t, 0);
390 }
391
392 /*
393  * Externally callable EC access functions. For now, assume 1 EC only
394  */
395 int ec_burst_enable(void)
396 {
397         if (!first_ec)
398                 return -ENODEV;
399         return acpi_ec_burst_enable(first_ec);
400 }
401
402 EXPORT_SYMBOL(ec_burst_enable);
403
404 int ec_burst_disable(void)
405 {
406         if (!first_ec)
407                 return -ENODEV;
408         return acpi_ec_burst_disable(first_ec);
409 }
410
411 EXPORT_SYMBOL(ec_burst_disable);
412
413 int ec_read(u8 addr, u8 * val)
414 {
415         int err;
416         u8 temp_data;
417
418         if (!first_ec)
419                 return -ENODEV;
420
421         err = acpi_ec_read(first_ec, addr, &temp_data);
422
423         if (!err) {
424                 *val = temp_data;
425                 return 0;
426         } else
427                 return err;
428 }
429
430 EXPORT_SYMBOL(ec_read);
431
432 int ec_write(u8 addr, u8 val)
433 {
434         int err;
435
436         if (!first_ec)
437                 return -ENODEV;
438
439         err = acpi_ec_write(first_ec, addr, val);
440
441         return err;
442 }
443
444 EXPORT_SYMBOL(ec_write);
445
446 int ec_transaction(u8 command,
447                    const u8 * wdata, unsigned wdata_len,
448                    u8 * rdata, unsigned rdata_len,
449                    int force_poll)
450 {
451         struct transaction t = {.command = command,
452                                 .wdata = wdata, .rdata = rdata,
453                                 .wlen = wdata_len, .rlen = rdata_len};
454         if (!first_ec)
455                 return -ENODEV;
456
457         return acpi_ec_transaction(first_ec, &t, force_poll);
458 }
459
460 EXPORT_SYMBOL(ec_transaction);
461
462 static int acpi_ec_query(struct acpi_ec *ec, u8 * data)
463 {
464         int result;
465         u8 d;
466         struct transaction t = {.command = ACPI_EC_COMMAND_QUERY,
467                                 .wdata = NULL, .rdata = &d,
468                                 .wlen = 0, .rlen = 1};
469         if (!ec || !data)
470                 return -EINVAL;
471
472         /*
473          * Query the EC to find out which _Qxx method we need to evaluate.
474          * Note that successful completion of the query causes the ACPI_EC_SCI
475          * bit to be cleared (and thus clearing the interrupt source).
476          */
477
478         result = acpi_ec_transaction(ec, &t, 0);
479         if (result)
480                 return result;
481
482         if (!d)
483                 return -ENODATA;
484
485         *data = d;
486         return 0;
487 }
488
489 /* --------------------------------------------------------------------------
490                                 Event Management
491    -------------------------------------------------------------------------- */
492 int acpi_ec_add_query_handler(struct acpi_ec *ec, u8 query_bit,
493                               acpi_handle handle, acpi_ec_query_func func,
494                               void *data)
495 {
496         struct acpi_ec_query_handler *handler =
497             kzalloc(sizeof(struct acpi_ec_query_handler), GFP_KERNEL);
498         if (!handler)
499                 return -ENOMEM;
500
501         handler->query_bit = query_bit;
502         handler->handle = handle;
503         handler->func = func;
504         handler->data = data;
505         mutex_lock(&ec->lock);
506         list_add(&handler->node, &ec->list);
507         mutex_unlock(&ec->lock);
508         return 0;
509 }
510
511 EXPORT_SYMBOL_GPL(acpi_ec_add_query_handler);
512
513 void acpi_ec_remove_query_handler(struct acpi_ec *ec, u8 query_bit)
514 {
515         struct acpi_ec_query_handler *handler, *tmp;
516         mutex_lock(&ec->lock);
517         list_for_each_entry_safe(handler, tmp, &ec->list, node) {
518                 if (query_bit == handler->query_bit) {
519                         list_del(&handler->node);
520                         kfree(handler);
521                 }
522         }
523         mutex_unlock(&ec->lock);
524 }
525
526 EXPORT_SYMBOL_GPL(acpi_ec_remove_query_handler);
527
528 static void acpi_ec_gpe_query(void *ec_cxt)
529 {
530         struct acpi_ec *ec = ec_cxt;
531         u8 value = 0;
532         struct acpi_ec_query_handler *handler, copy;
533
534         if (!ec || acpi_ec_query(ec, &value))
535                 return;
536         mutex_lock(&ec->lock);
537         list_for_each_entry(handler, &ec->list, node) {
538                 if (value == handler->query_bit) {
539                         /* have custom handler for this bit */
540                         memcpy(&copy, handler, sizeof(copy));
541                         mutex_unlock(&ec->lock);
542                         if (copy.func) {
543                                 copy.func(copy.data);
544                         } else if (copy.handle) {
545                                 acpi_evaluate_object(copy.handle, NULL, NULL, NULL);
546                         }
547                         return;
548                 }
549         }
550         mutex_unlock(&ec->lock);
551 }
552
553 static u32 acpi_ec_gpe_handler(void *data)
554 {
555         struct acpi_ec *ec = data;
556         u8 status;
557
558         pr_debug(PREFIX "~~~> interrupt\n");
559         status = acpi_ec_read_status(ec);
560
561         gpe_transaction(ec, status);
562         if (ec_transaction_done(ec) && (status & ACPI_EC_FLAG_IBF) == 0)
563                 wake_up(&ec->wait);
564
565         ec_check_sci(ec, status);
566         if (!test_bit(EC_FLAGS_GPE_MODE, &ec->flags) &&
567             !test_bit(EC_FLAGS_NO_GPE, &ec->flags)) {
568                 /* this is non-query, must be confirmation */
569                 if (printk_ratelimit())
570                         pr_info(PREFIX "non-query interrupt received,"
571                                 " switching to interrupt mode\n");
572                 set_bit(EC_FLAGS_GPE_MODE, &ec->flags);
573         }
574         return ACPI_INTERRUPT_HANDLED;
575 }
576
577 /* --------------------------------------------------------------------------
578                              Address Space Management
579    -------------------------------------------------------------------------- */
580
581 static acpi_status
582 acpi_ec_space_handler(u32 function, acpi_physical_address address,
583                       u32 bits, acpi_integer *value,
584                       void *handler_context, void *region_context)
585 {
586         struct acpi_ec *ec = handler_context;
587         int result = 0, i;
588         u8 temp = 0;
589
590         if ((address > 0xFF) || !value || !handler_context)
591                 return AE_BAD_PARAMETER;
592
593         if (function != ACPI_READ && function != ACPI_WRITE)
594                 return AE_BAD_PARAMETER;
595
596         if (bits != 8 && acpi_strict)
597                 return AE_BAD_PARAMETER;
598
599         acpi_ec_burst_enable(ec);
600
601         if (function == ACPI_READ) {
602                 result = acpi_ec_read(ec, address, &temp);
603                 *value = temp;
604         } else {
605                 temp = 0xff & (*value);
606                 result = acpi_ec_write(ec, address, temp);
607         }
608
609         for (i = 8; unlikely(bits - i > 0); i += 8) {
610                 ++address;
611                 if (function == ACPI_READ) {
612                         result = acpi_ec_read(ec, address, &temp);
613                         (*value) |= ((acpi_integer)temp) << i;
614                 } else {
615                         temp = 0xff & ((*value) >> i);
616                         result = acpi_ec_write(ec, address, temp);
617                 }
618         }
619
620         acpi_ec_burst_disable(ec);
621
622         switch (result) {
623         case -EINVAL:
624                 return AE_BAD_PARAMETER;
625                 break;
626         case -ENODEV:
627                 return AE_NOT_FOUND;
628                 break;
629         case -ETIME:
630                 return AE_TIME;
631                 break;
632         default:
633                 return AE_OK;
634         }
635 }
636
637 /* --------------------------------------------------------------------------
638                               FS Interface (/proc)
639    -------------------------------------------------------------------------- */
640
641 static struct proc_dir_entry *acpi_ec_dir;
642
643 static int acpi_ec_read_info(struct seq_file *seq, void *offset)
644 {
645         struct acpi_ec *ec = seq->private;
646
647         if (!ec)
648                 goto end;
649
650         seq_printf(seq, "gpe:\t\t\t0x%02x\n", (u32) ec->gpe);
651         seq_printf(seq, "ports:\t\t\t0x%02x, 0x%02x\n",
652                    (unsigned)ec->command_addr, (unsigned)ec->data_addr);
653         seq_printf(seq, "use global lock:\t%s\n",
654                    ec->global_lock ? "yes" : "no");
655       end:
656         return 0;
657 }
658
659 static int acpi_ec_info_open_fs(struct inode *inode, struct file *file)
660 {
661         return single_open(file, acpi_ec_read_info, PDE(inode)->data);
662 }
663
664 static struct file_operations acpi_ec_info_ops = {
665         .open = acpi_ec_info_open_fs,
666         .read = seq_read,
667         .llseek = seq_lseek,
668         .release = single_release,
669         .owner = THIS_MODULE,
670 };
671
672 static int acpi_ec_add_fs(struct acpi_device *device)
673 {
674         struct proc_dir_entry *entry = NULL;
675
676         if (!acpi_device_dir(device)) {
677                 acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device),
678                                                      acpi_ec_dir);
679                 if (!acpi_device_dir(device))
680                         return -ENODEV;
681         }
682
683         entry = proc_create_data(ACPI_EC_FILE_INFO, S_IRUGO,
684                                  acpi_device_dir(device),
685                                  &acpi_ec_info_ops, acpi_driver_data(device));
686         if (!entry)
687                 return -ENODEV;
688         return 0;
689 }
690
691 static int acpi_ec_remove_fs(struct acpi_device *device)
692 {
693
694         if (acpi_device_dir(device)) {
695                 remove_proc_entry(ACPI_EC_FILE_INFO, acpi_device_dir(device));
696                 remove_proc_entry(acpi_device_bid(device), acpi_ec_dir);
697                 acpi_device_dir(device) = NULL;
698         }
699
700         return 0;
701 }
702
703 /* --------------------------------------------------------------------------
704                                Driver Interface
705    -------------------------------------------------------------------------- */
706 static acpi_status
707 ec_parse_io_ports(struct acpi_resource *resource, void *context);
708
709 static struct acpi_ec *make_acpi_ec(void)
710 {
711         struct acpi_ec *ec = kzalloc(sizeof(struct acpi_ec), GFP_KERNEL);
712         if (!ec)
713                 return NULL;
714         ec->flags = 1 << EC_FLAGS_QUERY_PENDING;
715         mutex_init(&ec->lock);
716         init_waitqueue_head(&ec->wait);
717         INIT_LIST_HEAD(&ec->list);
718         spin_lock_init(&ec->curr_lock);
719         return ec;
720 }
721
722 static acpi_status
723 acpi_ec_register_query_methods(acpi_handle handle, u32 level,
724                                void *context, void **return_value)
725 {
726         struct acpi_namespace_node *node = handle;
727         struct acpi_ec *ec = context;
728         int value = 0;
729         if (sscanf(node->name.ascii, "_Q%x", &value) == 1) {
730                 acpi_ec_add_query_handler(ec, value, handle, NULL, NULL);
731         }
732         return AE_OK;
733 }
734
735 static acpi_status
736 ec_parse_device(acpi_handle handle, u32 Level, void *context, void **retval)
737 {
738         acpi_status status;
739
740         struct acpi_ec *ec = context;
741         status = acpi_walk_resources(handle, METHOD_NAME__CRS,
742                                      ec_parse_io_ports, ec);
743         if (ACPI_FAILURE(status))
744                 return status;
745
746         /* Get GPE bit assignment (EC events). */
747         /* TODO: Add support for _GPE returning a package */
748         status = acpi_evaluate_integer(handle, "_GPE", NULL, &ec->gpe);
749         if (ACPI_FAILURE(status))
750                 return status;
751         /* Use the global lock for all EC transactions? */
752         acpi_evaluate_integer(handle, "_GLK", NULL, &ec->global_lock);
753         ec->handle = handle;
754         return AE_CTRL_TERMINATE;
755 }
756
757 static void ec_remove_handlers(struct acpi_ec *ec)
758 {
759         if (ACPI_FAILURE(acpi_remove_address_space_handler(ec->handle,
760                                 ACPI_ADR_SPACE_EC, &acpi_ec_space_handler)))
761                 pr_err(PREFIX "failed to remove space handler\n");
762         if (ACPI_FAILURE(acpi_remove_gpe_handler(NULL, ec->gpe,
763                                 &acpi_ec_gpe_handler)))
764                 pr_err(PREFIX "failed to remove gpe handler\n");
765         clear_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags);
766 }
767
768 static int acpi_ec_add(struct acpi_device *device)
769 {
770         struct acpi_ec *ec = NULL;
771
772         if (!device)
773                 return -EINVAL;
774         strcpy(acpi_device_name(device), ACPI_EC_DEVICE_NAME);
775         strcpy(acpi_device_class(device), ACPI_EC_CLASS);
776
777         /* Check for boot EC */
778         if (boot_ec &&
779             (boot_ec->handle == device->handle ||
780              boot_ec->handle == ACPI_ROOT_OBJECT)) {
781                 ec = boot_ec;
782                 boot_ec = NULL;
783         } else {
784                 ec = make_acpi_ec();
785                 if (!ec)
786                         return -ENOMEM;
787                 if (ec_parse_device(device->handle, 0, ec, NULL) !=
788                     AE_CTRL_TERMINATE) {
789                         kfree(ec);
790                         return -EINVAL;
791                 }
792         }
793
794         ec->handle = device->handle;
795
796         /* Find and register all query methods */
797         acpi_walk_namespace(ACPI_TYPE_METHOD, ec->handle, 1,
798                             acpi_ec_register_query_methods, ec, NULL);
799
800         if (!first_ec)
801                 first_ec = ec;
802         device->driver_data = ec;
803         acpi_ec_add_fs(device);
804         pr_info(PREFIX "GPE = 0x%lx, I/O: command/status = 0x%lx, data = 0x%lx\n",
805                           ec->gpe, ec->command_addr, ec->data_addr);
806         pr_info(PREFIX "driver started in %s mode\n",
807                 (test_bit(EC_FLAGS_GPE_MODE, &ec->flags))?"interrupt":"poll");
808         return 0;
809 }
810
811 static int acpi_ec_remove(struct acpi_device *device, int type)
812 {
813         struct acpi_ec *ec;
814         struct acpi_ec_query_handler *handler, *tmp;
815
816         if (!device)
817                 return -EINVAL;
818
819         ec = acpi_driver_data(device);
820         mutex_lock(&ec->lock);
821         list_for_each_entry_safe(handler, tmp, &ec->list, node) {
822                 list_del(&handler->node);
823                 kfree(handler);
824         }
825         mutex_unlock(&ec->lock);
826         acpi_ec_remove_fs(device);
827         device->driver_data = NULL;
828         if (ec == first_ec)
829                 first_ec = NULL;
830         kfree(ec);
831         return 0;
832 }
833
834 static acpi_status
835 ec_parse_io_ports(struct acpi_resource *resource, void *context)
836 {
837         struct acpi_ec *ec = context;
838
839         if (resource->type != ACPI_RESOURCE_TYPE_IO)
840                 return AE_OK;
841
842         /*
843          * The first address region returned is the data port, and
844          * the second address region returned is the status/command
845          * port.
846          */
847         if (ec->data_addr == 0)
848                 ec->data_addr = resource->data.io.minimum;
849         else if (ec->command_addr == 0)
850                 ec->command_addr = resource->data.io.minimum;
851         else
852                 return AE_CTRL_TERMINATE;
853
854         return AE_OK;
855 }
856
857 static int ec_install_handlers(struct acpi_ec *ec)
858 {
859         acpi_status status;
860         if (test_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags))
861                 return 0;
862         status = acpi_install_gpe_handler(NULL, ec->gpe,
863                                   ACPI_GPE_EDGE_TRIGGERED,
864                                   &acpi_ec_gpe_handler, ec);
865         if (ACPI_FAILURE(status))
866                 return -ENODEV;
867         acpi_set_gpe_type(NULL, ec->gpe, ACPI_GPE_TYPE_RUNTIME);
868         acpi_enable_gpe(NULL, ec->gpe, ACPI_NOT_ISR);
869         status = acpi_install_address_space_handler(ec->handle,
870                                                     ACPI_ADR_SPACE_EC,
871                                                     &acpi_ec_space_handler,
872                                                     NULL, ec);
873         if (ACPI_FAILURE(status)) {
874                 if (status == AE_NOT_FOUND) {
875                         /*
876                          * Maybe OS fails in evaluating the _REG object.
877                          * The AE_NOT_FOUND error will be ignored and OS
878                          * continue to initialize EC.
879                          */
880                         printk(KERN_ERR "Fail in evaluating the _REG object"
881                                 " of EC device. Broken bios is suspected.\n");
882                 } else {
883                         acpi_remove_gpe_handler(NULL, ec->gpe,
884                                 &acpi_ec_gpe_handler);
885                         return -ENODEV;
886                 }
887         }
888
889         set_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags);
890         return 0;
891 }
892
893 static int acpi_ec_start(struct acpi_device *device)
894 {
895         struct acpi_ec *ec;
896         int ret = 0;
897
898         if (!device)
899                 return -EINVAL;
900
901         ec = acpi_driver_data(device);
902
903         if (!ec)
904                 return -EINVAL;
905
906         ret = ec_install_handlers(ec);
907
908         /* EC is fully operational, allow queries */
909         clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags);
910         return ret;
911 }
912
913 static int acpi_ec_stop(struct acpi_device *device, int type)
914 {
915         struct acpi_ec *ec;
916         if (!device)
917                 return -EINVAL;
918         ec = acpi_driver_data(device);
919         if (!ec)
920                 return -EINVAL;
921         ec_remove_handlers(ec);
922
923         return 0;
924 }
925
926 int __init acpi_boot_ec_enable(void)
927 {
928         if (!boot_ec || test_bit(EC_FLAGS_HANDLERS_INSTALLED, &boot_ec->flags))
929                 return 0;
930         if (!ec_install_handlers(boot_ec)) {
931                 first_ec = boot_ec;
932                 return 0;
933         }
934         return -EFAULT;
935 }
936
937 static const struct acpi_device_id ec_device_ids[] = {
938         {"PNP0C09", 0},
939         {"", 0},
940 };
941
942 int __init acpi_ec_ecdt_probe(void)
943 {
944         int ret;
945         acpi_status status;
946         struct acpi_table_ecdt *ecdt_ptr;
947
948         boot_ec = make_acpi_ec();
949         if (!boot_ec)
950                 return -ENOMEM;
951         /*
952          * Generate a boot ec context
953          */
954         status = acpi_get_table(ACPI_SIG_ECDT, 1,
955                                 (struct acpi_table_header **)&ecdt_ptr);
956         if (ACPI_SUCCESS(status)) {
957                 pr_info(PREFIX "EC description table is found, configuring boot EC\n");
958                 boot_ec->command_addr = ecdt_ptr->control.address;
959                 boot_ec->data_addr = ecdt_ptr->data.address;
960                 if (dmi_check_system(ec_dmi_table)) {
961                         /*
962                          * If the board falls into ec_dmi_table, it means
963                          * that ECDT table gives the incorrect command/status
964                          * & data I/O address. Just fix it.
965                          */
966                         boot_ec->data_addr = ecdt_ptr->control.address;
967                         boot_ec->command_addr = ecdt_ptr->data.address;
968                 }
969                 boot_ec->gpe = ecdt_ptr->gpe;
970                 boot_ec->handle = ACPI_ROOT_OBJECT;
971                 acpi_get_handle(ACPI_ROOT_OBJECT, ecdt_ptr->id, &boot_ec->handle);
972         } else {
973                 /* This workaround is needed only on some broken machines,
974                  * which require early EC, but fail to provide ECDT */
975                 acpi_handle x;
976                 printk(KERN_DEBUG PREFIX "Look up EC in DSDT\n");
977                 status = acpi_get_devices(ec_device_ids[0].id, ec_parse_device,
978                                                 boot_ec, NULL);
979                 /* Check that acpi_get_devices actually find something */
980                 if (ACPI_FAILURE(status) || !boot_ec->handle)
981                         goto error;
982                 /* We really need to limit this workaround, the only ASUS,
983                  * which needs it, has fake EC._INI method, so use it as flag.
984                  * Keep boot_ec struct as it will be needed soon.
985                  */
986                 if (ACPI_FAILURE(acpi_get_handle(boot_ec->handle, "_INI", &x)))
987                         return -ENODEV;
988         }
989
990         ret = ec_install_handlers(boot_ec);
991         if (!ret) {
992                 first_ec = boot_ec;
993                 return 0;
994         }
995       error:
996         kfree(boot_ec);
997         boot_ec = NULL;
998         return -ENODEV;
999 }
1000
1001 static int acpi_ec_suspend(struct acpi_device *device, pm_message_t state)
1002 {
1003         struct acpi_ec *ec = acpi_driver_data(device);
1004         /* Stop using GPE */
1005         set_bit(EC_FLAGS_NO_GPE, &ec->flags);
1006         clear_bit(EC_FLAGS_GPE_MODE, &ec->flags);
1007         acpi_disable_gpe(NULL, ec->gpe, ACPI_NOT_ISR);
1008         return 0;
1009 }
1010
1011 static int acpi_ec_resume(struct acpi_device *device)
1012 {
1013         struct acpi_ec *ec = acpi_driver_data(device);
1014         /* Enable use of GPE back */
1015         clear_bit(EC_FLAGS_NO_GPE, &ec->flags);
1016         acpi_enable_gpe(NULL, ec->gpe, ACPI_NOT_ISR);
1017         return 0;
1018 }
1019
1020 static struct acpi_driver acpi_ec_driver = {
1021         .name = "ec",
1022         .class = ACPI_EC_CLASS,
1023         .ids = ec_device_ids,
1024         .ops = {
1025                 .add = acpi_ec_add,
1026                 .remove = acpi_ec_remove,
1027                 .start = acpi_ec_start,
1028                 .stop = acpi_ec_stop,
1029                 .suspend = acpi_ec_suspend,
1030                 .resume = acpi_ec_resume,
1031                 },
1032 };
1033
1034 static int __init acpi_ec_init(void)
1035 {
1036         int result = 0;
1037
1038         if (acpi_disabled)
1039                 return 0;
1040
1041         acpi_ec_dir = proc_mkdir(ACPI_EC_CLASS, acpi_root_dir);
1042         if (!acpi_ec_dir)
1043                 return -ENODEV;
1044
1045         /* Now register the driver for the EC */
1046         result = acpi_bus_register_driver(&acpi_ec_driver);
1047         if (result < 0) {
1048                 remove_proc_entry(ACPI_EC_CLASS, acpi_root_dir);
1049                 return -ENODEV;
1050         }
1051
1052         return result;
1053 }
1054
1055 subsys_initcall(acpi_ec_init);
1056
1057 /* EC driver currently not unloadable */
1058 #if 0
1059 static void __exit acpi_ec_exit(void)
1060 {
1061
1062         acpi_bus_unregister_driver(&acpi_ec_driver);
1063
1064         remove_proc_entry(ACPI_EC_CLASS, acpi_root_dir);
1065
1066         return;
1067 }
1068 #endif  /* 0 */