acpi: use non-racy method for proc entries creation
[linux-2.6.git] / drivers / acpi / ec.c
1 /*
2  *  ec.c - ACPI Embedded Controller Driver (v2.0)
3  *
4  *  Copyright (C) 2006, 2007 Alexey Starikovskiy <alexey.y.starikovskiy@intel.com>
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 print outs*/
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 <asm/io.h>
42 #include <acpi/acpi_bus.h>
43 #include <acpi/acpi_drivers.h>
44 #include <acpi/actypes.h>
45
46 #define ACPI_EC_CLASS                   "embedded_controller"
47 #define ACPI_EC_DEVICE_NAME             "Embedded Controller"
48 #define ACPI_EC_FILE_INFO               "info"
49
50 #undef PREFIX
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 /* EC events */
69 enum ec_event {
70         ACPI_EC_EVENT_OBF_1 = 1,        /* Output buffer full */
71         ACPI_EC_EVENT_IBF_0,            /* Input buffer empty */
72 };
73
74 #define ACPI_EC_DELAY           500     /* Wait 500ms max. during EC ops */
75 #define ACPI_EC_UDELAY_GLK      1000    /* Wait 1ms max. to get global lock */
76
77 enum {
78         EC_FLAGS_WAIT_GPE = 0,          /* Don't check status until GPE arrives */
79         EC_FLAGS_QUERY_PENDING,         /* Query is pending */
80         EC_FLAGS_GPE_MODE,              /* Expect GPE to be sent for status change */
81         EC_FLAGS_NO_ADDRESS_GPE,        /* Expect GPE only for non-address event */
82         EC_FLAGS_ADDRESS,               /* Address is being written */
83         EC_FLAGS_NO_WDATA_GPE,          /* Don't expect WDATA GPE event */
84         EC_FLAGS_WDATA,                 /* Data is being written */
85         EC_FLAGS_NO_OBF1_GPE,           /* Don't expect GPE before read */
86 };
87
88 static int acpi_ec_remove(struct acpi_device *device, int type);
89 static int acpi_ec_start(struct acpi_device *device);
90 static int acpi_ec_stop(struct acpi_device *device, int type);
91 static int acpi_ec_add(struct acpi_device *device);
92
93 static const struct acpi_device_id ec_device_ids[] = {
94         {"PNP0C09", 0},
95         {"", 0},
96 };
97
98 static struct acpi_driver acpi_ec_driver = {
99         .name = "ec",
100         .class = ACPI_EC_CLASS,
101         .ids = ec_device_ids,
102         .ops = {
103                 .add = acpi_ec_add,
104                 .remove = acpi_ec_remove,
105                 .start = acpi_ec_start,
106                 .stop = acpi_ec_stop,
107                 },
108 };
109
110 /* If we find an EC via the ECDT, we need to keep a ptr to its context */
111 /* External interfaces use first EC only, so remember */
112 typedef int (*acpi_ec_query_func) (void *data);
113
114 struct acpi_ec_query_handler {
115         struct list_head node;
116         acpi_ec_query_func func;
117         acpi_handle handle;
118         void *data;
119         u8 query_bit;
120 };
121
122 static struct acpi_ec {
123         acpi_handle handle;
124         unsigned long gpe;
125         unsigned long command_addr;
126         unsigned long data_addr;
127         unsigned long global_lock;
128         unsigned long flags;
129         struct mutex lock;
130         wait_queue_head_t wait;
131         struct list_head list;
132         u8 handlers_installed;
133 } *boot_ec, *first_ec;
134
135 /* --------------------------------------------------------------------------
136                              Transaction Management
137    -------------------------------------------------------------------------- */
138
139 static inline u8 acpi_ec_read_status(struct acpi_ec *ec)
140 {
141         u8 x = inb(ec->command_addr);
142         pr_debug(PREFIX "---> status = 0x%2.2x\n", x);
143         return x;
144 }
145
146 static inline u8 acpi_ec_read_data(struct acpi_ec *ec)
147 {
148         u8 x = inb(ec->data_addr);
149         pr_debug(PREFIX "---> data = 0x%2.2x\n", x);
150         return inb(ec->data_addr);
151 }
152
153 static inline void acpi_ec_write_cmd(struct acpi_ec *ec, u8 command)
154 {
155         pr_debug(PREFIX "<--- command = 0x%2.2x\n", command);
156         outb(command, ec->command_addr);
157 }
158
159 static inline void acpi_ec_write_data(struct acpi_ec *ec, u8 data)
160 {
161         pr_debug(PREFIX "<--- data = 0x%2.2x\n", data);
162         outb(data, ec->data_addr);
163 }
164
165 static inline int acpi_ec_check_status(struct acpi_ec *ec, enum ec_event event)
166 {
167         if (test_bit(EC_FLAGS_WAIT_GPE, &ec->flags))
168                 return 0;
169         if (event == ACPI_EC_EVENT_OBF_1) {
170                 if (acpi_ec_read_status(ec) & ACPI_EC_FLAG_OBF)
171                         return 1;
172         } else if (event == ACPI_EC_EVENT_IBF_0) {
173                 if (!(acpi_ec_read_status(ec) & ACPI_EC_FLAG_IBF))
174                         return 1;
175         }
176
177         return 0;
178 }
179
180 static int acpi_ec_wait(struct acpi_ec *ec, enum ec_event event, int force_poll)
181 {
182         int ret = 0;
183
184         if (unlikely(event == ACPI_EC_EVENT_OBF_1 &&
185                      test_bit(EC_FLAGS_NO_OBF1_GPE, &ec->flags)))
186                 force_poll = 1;
187         if (unlikely(test_bit(EC_FLAGS_ADDRESS, &ec->flags) &&
188                      test_bit(EC_FLAGS_NO_ADDRESS_GPE, &ec->flags)))
189                 force_poll = 1;
190         if (unlikely(test_bit(EC_FLAGS_WDATA, &ec->flags) &&
191                      test_bit(EC_FLAGS_NO_WDATA_GPE, &ec->flags)))
192                 force_poll = 1;
193         if (likely(test_bit(EC_FLAGS_GPE_MODE, &ec->flags)) &&
194             likely(!force_poll)) {
195                 if (wait_event_timeout(ec->wait, acpi_ec_check_status(ec, event),
196                                        msecs_to_jiffies(ACPI_EC_DELAY)))
197                         goto end;
198                 clear_bit(EC_FLAGS_WAIT_GPE, &ec->flags);
199                 if (acpi_ec_check_status(ec, event)) {
200                         if (event == ACPI_EC_EVENT_OBF_1) {
201                                 /* miss OBF_1 GPE, don't expect it */
202                                 pr_info(PREFIX "missing OBF confirmation, "
203                                         "don't expect it any longer.\n");
204                                 set_bit(EC_FLAGS_NO_OBF1_GPE, &ec->flags);
205                         } else if (test_bit(EC_FLAGS_ADDRESS, &ec->flags)) {
206                                 /* miss address GPE, don't expect it anymore */
207                                 pr_info(PREFIX "missing address confirmation, "
208                                         "don't expect it any longer.\n");
209                                 set_bit(EC_FLAGS_NO_ADDRESS_GPE, &ec->flags);
210                         } else if (test_bit(EC_FLAGS_WDATA, &ec->flags)) {
211                                 /* miss write data GPE, don't expect it */
212                                 pr_info(PREFIX "missing write data confirmation, "
213                                         "don't expect it any longer.\n");
214                                 set_bit(EC_FLAGS_NO_WDATA_GPE, &ec->flags);
215                         } else {
216                                 /* missing GPEs, switch back to poll mode */
217                                 if (printk_ratelimit())
218                                         pr_info(PREFIX "missing confirmations, "
219                                                 "switch off interrupt mode.\n");
220                                 clear_bit(EC_FLAGS_GPE_MODE, &ec->flags);
221                         }
222                         goto end;
223                 }
224         } else {
225                 unsigned long delay = jiffies + msecs_to_jiffies(ACPI_EC_DELAY);
226                 clear_bit(EC_FLAGS_WAIT_GPE, &ec->flags);
227                 while (time_before(jiffies, delay)) {
228                         if (acpi_ec_check_status(ec, event))
229                                 goto end;
230                 }
231         }
232         pr_err(PREFIX "acpi_ec_wait timeout,"
233                                " status = %d, expect_event = %d\n",
234                                acpi_ec_read_status(ec), event);
235         ret = -ETIME;
236       end:
237         clear_bit(EC_FLAGS_ADDRESS, &ec->flags);
238         return ret;
239 }
240
241 static int acpi_ec_transaction_unlocked(struct acpi_ec *ec, u8 command,
242                                         const u8 * wdata, unsigned wdata_len,
243                                         u8 * rdata, unsigned rdata_len,
244                                         int force_poll)
245 {
246         int result = 0;
247         set_bit(EC_FLAGS_WAIT_GPE, &ec->flags);
248         acpi_ec_write_cmd(ec, command);
249         pr_debug(PREFIX "transaction start\n");
250         for (; wdata_len > 0; --wdata_len) {
251                 result = acpi_ec_wait(ec, ACPI_EC_EVENT_IBF_0, force_poll);
252                 if (result) {
253                         pr_err(PREFIX
254                                "write_cmd timeout, command = %d\n", command);
255                         goto end;
256                 }
257                 /* mark the address byte written to EC */
258                 if (rdata_len + wdata_len > 1)
259                         set_bit(EC_FLAGS_ADDRESS, &ec->flags);
260                 set_bit(EC_FLAGS_WAIT_GPE, &ec->flags);
261                 acpi_ec_write_data(ec, *(wdata++));
262         }
263
264         if (!rdata_len) {
265                 set_bit(EC_FLAGS_WDATA, &ec->flags);
266                 result = acpi_ec_wait(ec, ACPI_EC_EVENT_IBF_0, force_poll);
267                 if (result) {
268                         pr_err(PREFIX
269                                "finish-write timeout, command = %d\n", command);
270                         goto end;
271                 }
272         } else if (command == ACPI_EC_COMMAND_QUERY)
273                 clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags);
274
275         for (; rdata_len > 0; --rdata_len) {
276                 result = acpi_ec_wait(ec, ACPI_EC_EVENT_OBF_1, force_poll);
277                 if (result) {
278                         pr_err(PREFIX "read timeout, command = %d\n", command);
279                         goto end;
280                 }
281                 /* Don't expect GPE after last read */
282                 if (rdata_len > 1)
283                         set_bit(EC_FLAGS_WAIT_GPE, &ec->flags);
284                 *(rdata++) = acpi_ec_read_data(ec);
285         }
286       end:
287         pr_debug(PREFIX "transaction end\n");
288         return result;
289 }
290
291 static int acpi_ec_transaction(struct acpi_ec *ec, u8 command,
292                                const u8 * wdata, unsigned wdata_len,
293                                u8 * rdata, unsigned rdata_len,
294                                int force_poll)
295 {
296         int status;
297         u32 glk;
298
299         if (!ec || (wdata_len && !wdata) || (rdata_len && !rdata))
300                 return -EINVAL;
301
302         if (rdata)
303                 memset(rdata, 0, rdata_len);
304
305         mutex_lock(&ec->lock);
306         if (ec->global_lock) {
307                 status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk);
308                 if (ACPI_FAILURE(status)) {
309                         mutex_unlock(&ec->lock);
310                         return -ENODEV;
311                 }
312         }
313
314         status = acpi_ec_wait(ec, ACPI_EC_EVENT_IBF_0, 0);
315         if (status) {
316                 pr_err(PREFIX "input buffer is not empty, "
317                                 "aborting transaction\n");
318                 goto end;
319         }
320
321         status = acpi_ec_transaction_unlocked(ec, command,
322                                               wdata, wdata_len,
323                                               rdata, rdata_len,
324                                               force_poll);
325
326       end:
327
328         if (ec->global_lock)
329                 acpi_release_global_lock(glk);
330         mutex_unlock(&ec->lock);
331
332         return status;
333 }
334
335 /*
336  * Note: samsung nv5000 doesn't work with ec burst mode.
337  * http://bugzilla.kernel.org/show_bug.cgi?id=4980
338  */
339 int acpi_ec_burst_enable(struct acpi_ec *ec)
340 {
341         u8 d;
342         return acpi_ec_transaction(ec, ACPI_EC_BURST_ENABLE, NULL, 0, &d, 1, 0);
343 }
344
345 int acpi_ec_burst_disable(struct acpi_ec *ec)
346 {
347         return acpi_ec_transaction(ec, ACPI_EC_BURST_DISABLE, NULL, 0, NULL, 0, 0);
348 }
349
350 static int acpi_ec_read(struct acpi_ec *ec, u8 address, u8 * data)
351 {
352         int result;
353         u8 d;
354
355         result = acpi_ec_transaction(ec, ACPI_EC_COMMAND_READ,
356                                      &address, 1, &d, 1, 0);
357         *data = d;
358         return result;
359 }
360
361 static int acpi_ec_write(struct acpi_ec *ec, u8 address, u8 data)
362 {
363         u8 wdata[2] = { address, data };
364         return acpi_ec_transaction(ec, ACPI_EC_COMMAND_WRITE,
365                                    wdata, 2, NULL, 0, 0);
366 }
367
368 /*
369  * Externally callable EC access functions. For now, assume 1 EC only
370  */
371 int ec_burst_enable(void)
372 {
373         if (!first_ec)
374                 return -ENODEV;
375         return acpi_ec_burst_enable(first_ec);
376 }
377
378 EXPORT_SYMBOL(ec_burst_enable);
379
380 int ec_burst_disable(void)
381 {
382         if (!first_ec)
383                 return -ENODEV;
384         return acpi_ec_burst_disable(first_ec);
385 }
386
387 EXPORT_SYMBOL(ec_burst_disable);
388
389 int ec_read(u8 addr, u8 * val)
390 {
391         int err;
392         u8 temp_data;
393
394         if (!first_ec)
395                 return -ENODEV;
396
397         err = acpi_ec_read(first_ec, addr, &temp_data);
398
399         if (!err) {
400                 *val = temp_data;
401                 return 0;
402         } else
403                 return err;
404 }
405
406 EXPORT_SYMBOL(ec_read);
407
408 int ec_write(u8 addr, u8 val)
409 {
410         int err;
411
412         if (!first_ec)
413                 return -ENODEV;
414
415         err = acpi_ec_write(first_ec, addr, val);
416
417         return err;
418 }
419
420 EXPORT_SYMBOL(ec_write);
421
422 int ec_transaction(u8 command,
423                    const u8 * wdata, unsigned wdata_len,
424                    u8 * rdata, unsigned rdata_len,
425                    int force_poll)
426 {
427         if (!first_ec)
428                 return -ENODEV;
429
430         return acpi_ec_transaction(first_ec, command, wdata,
431                                    wdata_len, rdata, rdata_len,
432                                    force_poll);
433 }
434
435 EXPORT_SYMBOL(ec_transaction);
436
437 static int acpi_ec_query(struct acpi_ec *ec, u8 * data)
438 {
439         int result;
440         u8 d;
441
442         if (!ec || !data)
443                 return -EINVAL;
444
445         /*
446          * Query the EC to find out which _Qxx method we need to evaluate.
447          * Note that successful completion of the query causes the ACPI_EC_SCI
448          * bit to be cleared (and thus clearing the interrupt source).
449          */
450
451         result = acpi_ec_transaction(ec, ACPI_EC_COMMAND_QUERY, NULL, 0, &d, 1, 0);
452         if (result)
453                 return result;
454
455         if (!d)
456                 return -ENODATA;
457
458         *data = d;
459         return 0;
460 }
461
462 /* --------------------------------------------------------------------------
463                                 Event Management
464    -------------------------------------------------------------------------- */
465 int acpi_ec_add_query_handler(struct acpi_ec *ec, u8 query_bit,
466                               acpi_handle handle, acpi_ec_query_func func,
467                               void *data)
468 {
469         struct acpi_ec_query_handler *handler =
470             kzalloc(sizeof(struct acpi_ec_query_handler), GFP_KERNEL);
471         if (!handler)
472                 return -ENOMEM;
473
474         handler->query_bit = query_bit;
475         handler->handle = handle;
476         handler->func = func;
477         handler->data = data;
478         mutex_lock(&ec->lock);
479         list_add(&handler->node, &ec->list);
480         mutex_unlock(&ec->lock);
481         return 0;
482 }
483
484 EXPORT_SYMBOL_GPL(acpi_ec_add_query_handler);
485
486 void acpi_ec_remove_query_handler(struct acpi_ec *ec, u8 query_bit)
487 {
488         struct acpi_ec_query_handler *handler, *tmp;
489         mutex_lock(&ec->lock);
490         list_for_each_entry_safe(handler, tmp, &ec->list, node) {
491                 if (query_bit == handler->query_bit) {
492                         list_del(&handler->node);
493                         kfree(handler);
494                 }
495         }
496         mutex_unlock(&ec->lock);
497 }
498
499 EXPORT_SYMBOL_GPL(acpi_ec_remove_query_handler);
500
501 static void acpi_ec_gpe_query(void *ec_cxt)
502 {
503         struct acpi_ec *ec = ec_cxt;
504         u8 value = 0;
505         struct acpi_ec_query_handler *handler, copy;
506
507         if (!ec || acpi_ec_query(ec, &value))
508                 return;
509         mutex_lock(&ec->lock);
510         list_for_each_entry(handler, &ec->list, node) {
511                 if (value == handler->query_bit) {
512                         /* have custom handler for this bit */
513                         memcpy(&copy, handler, sizeof(copy));
514                         mutex_unlock(&ec->lock);
515                         if (copy.func) {
516                                 copy.func(copy.data);
517                         } else if (copy.handle) {
518                                 acpi_evaluate_object(copy.handle, NULL, NULL, NULL);
519                         }
520                         return;
521                 }
522         }
523         mutex_unlock(&ec->lock);
524 }
525
526 static u32 acpi_ec_gpe_handler(void *data)
527 {
528         acpi_status status = AE_OK;
529         struct acpi_ec *ec = data;
530
531         pr_debug(PREFIX "~~~> interrupt\n");
532         clear_bit(EC_FLAGS_WAIT_GPE, &ec->flags);
533         if (test_bit(EC_FLAGS_GPE_MODE, &ec->flags))
534                 wake_up(&ec->wait);
535
536         if (acpi_ec_read_status(ec) & ACPI_EC_FLAG_SCI) {
537                 if (!test_and_set_bit(EC_FLAGS_QUERY_PENDING, &ec->flags))
538                         status = acpi_os_execute(OSL_EC_BURST_HANDLER,
539                                 acpi_ec_gpe_query, ec);
540         } else if (unlikely(!test_bit(EC_FLAGS_GPE_MODE, &ec->flags))) {
541                 /* this is non-query, must be confirmation */
542                 if (printk_ratelimit())
543                         pr_info(PREFIX "non-query interrupt received,"
544                                 " switching to interrupt mode\n");
545                 set_bit(EC_FLAGS_GPE_MODE, &ec->flags);
546         }
547
548         return ACPI_SUCCESS(status) ?
549             ACPI_INTERRUPT_HANDLED : ACPI_INTERRUPT_NOT_HANDLED;
550 }
551
552 /* --------------------------------------------------------------------------
553                              Address Space Management
554    -------------------------------------------------------------------------- */
555
556 static acpi_status
557 acpi_ec_space_setup(acpi_handle region_handle,
558                     u32 function, void *handler_context, void **return_context)
559 {
560         /*
561          * The EC object is in the handler context and is needed
562          * when calling the acpi_ec_space_handler.
563          */
564         *return_context = (function != ACPI_REGION_DEACTIVATE) ?
565             handler_context : NULL;
566
567         return AE_OK;
568 }
569
570 static acpi_status
571 acpi_ec_space_handler(u32 function, acpi_physical_address address,
572                       u32 bits, acpi_integer *value,
573                       void *handler_context, void *region_context)
574 {
575         struct acpi_ec *ec = handler_context;
576         int result = 0, i;
577         u8 temp = 0;
578
579         if ((address > 0xFF) || !value || !handler_context)
580                 return AE_BAD_PARAMETER;
581
582         if (function != ACPI_READ && function != ACPI_WRITE)
583                 return AE_BAD_PARAMETER;
584
585         if (bits != 8 && acpi_strict)
586                 return AE_BAD_PARAMETER;
587
588         acpi_ec_burst_enable(ec);
589
590         if (function == ACPI_READ) {
591                 result = acpi_ec_read(ec, address, &temp);
592                 *value = temp;
593         } else {
594                 temp = 0xff & (*value);
595                 result = acpi_ec_write(ec, address, temp);
596         }
597
598         for (i = 8; unlikely(bits - i > 0); i += 8) {
599                 ++address;
600                 if (function == ACPI_READ) {
601                         result = acpi_ec_read(ec, address, &temp);
602                         (*value) |= ((acpi_integer)temp) << i;
603                 } else {
604                         temp = 0xff & ((*value) >> i);
605                         result = acpi_ec_write(ec, address, temp);
606                 }
607         }
608
609         acpi_ec_burst_disable(ec);
610
611         switch (result) {
612         case -EINVAL:
613                 return AE_BAD_PARAMETER;
614                 break;
615         case -ENODEV:
616                 return AE_NOT_FOUND;
617                 break;
618         case -ETIME:
619                 return AE_TIME;
620                 break;
621         default:
622                 return AE_OK;
623         }
624 }
625
626 /* --------------------------------------------------------------------------
627                               FS Interface (/proc)
628    -------------------------------------------------------------------------- */
629
630 static struct proc_dir_entry *acpi_ec_dir;
631
632 static int acpi_ec_read_info(struct seq_file *seq, void *offset)
633 {
634         struct acpi_ec *ec = seq->private;
635
636         if (!ec)
637                 goto end;
638
639         seq_printf(seq, "gpe:\t\t\t0x%02x\n", (u32) ec->gpe);
640         seq_printf(seq, "ports:\t\t\t0x%02x, 0x%02x\n",
641                    (unsigned)ec->command_addr, (unsigned)ec->data_addr);
642         seq_printf(seq, "use global lock:\t%s\n",
643                    ec->global_lock ? "yes" : "no");
644       end:
645         return 0;
646 }
647
648 static int acpi_ec_info_open_fs(struct inode *inode, struct file *file)
649 {
650         return single_open(file, acpi_ec_read_info, PDE(inode)->data);
651 }
652
653 static struct file_operations acpi_ec_info_ops = {
654         .open = acpi_ec_info_open_fs,
655         .read = seq_read,
656         .llseek = seq_lseek,
657         .release = single_release,
658         .owner = THIS_MODULE,
659 };
660
661 static int acpi_ec_add_fs(struct acpi_device *device)
662 {
663         struct proc_dir_entry *entry = NULL;
664
665         if (!acpi_device_dir(device)) {
666                 acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device),
667                                                      acpi_ec_dir);
668                 if (!acpi_device_dir(device))
669                         return -ENODEV;
670         }
671
672         entry = proc_create_data(ACPI_EC_FILE_INFO, S_IRUGO,
673                                  acpi_device_dir(device),
674                                  &acpi_ec_info_ops, acpi_driver_data(device));
675         if (!entry)
676                 return -ENODEV;
677         return 0;
678 }
679
680 static int acpi_ec_remove_fs(struct acpi_device *device)
681 {
682
683         if (acpi_device_dir(device)) {
684                 remove_proc_entry(ACPI_EC_FILE_INFO, acpi_device_dir(device));
685                 remove_proc_entry(acpi_device_bid(device), acpi_ec_dir);
686                 acpi_device_dir(device) = NULL;
687         }
688
689         return 0;
690 }
691
692 /* --------------------------------------------------------------------------
693                                Driver Interface
694    -------------------------------------------------------------------------- */
695 static acpi_status
696 ec_parse_io_ports(struct acpi_resource *resource, void *context);
697
698 static struct acpi_ec *make_acpi_ec(void)
699 {
700         struct acpi_ec *ec = kzalloc(sizeof(struct acpi_ec), GFP_KERNEL);
701         if (!ec)
702                 return NULL;
703         ec->flags = 1 << EC_FLAGS_QUERY_PENDING;
704         mutex_init(&ec->lock);
705         init_waitqueue_head(&ec->wait);
706         INIT_LIST_HEAD(&ec->list);
707         return ec;
708 }
709
710 static acpi_status
711 acpi_ec_register_query_methods(acpi_handle handle, u32 level,
712                                void *context, void **return_value)
713 {
714         struct acpi_namespace_node *node = handle;
715         struct acpi_ec *ec = context;
716         int value = 0;
717         if (sscanf(node->name.ascii, "_Q%x", &value) == 1) {
718                 acpi_ec_add_query_handler(ec, value, handle, NULL, NULL);
719         }
720         return AE_OK;
721 }
722
723 static acpi_status
724 ec_parse_device(acpi_handle handle, u32 Level, void *context, void **retval)
725 {
726         acpi_status status;
727
728         struct acpi_ec *ec = context;
729         status = acpi_walk_resources(handle, METHOD_NAME__CRS,
730                                      ec_parse_io_ports, ec);
731         if (ACPI_FAILURE(status))
732                 return status;
733
734         /* Get GPE bit assignment (EC events). */
735         /* TODO: Add support for _GPE returning a package */
736         status = acpi_evaluate_integer(handle, "_GPE", NULL, &ec->gpe);
737         if (ACPI_FAILURE(status))
738                 return status;
739         /* Find and register all query methods */
740         acpi_walk_namespace(ACPI_TYPE_METHOD, handle, 1,
741                             acpi_ec_register_query_methods, ec, NULL);
742         /* Use the global lock for all EC transactions? */
743         acpi_evaluate_integer(handle, "_GLK", NULL, &ec->global_lock);
744         ec->handle = handle;
745         return AE_CTRL_TERMINATE;
746 }
747
748 static void ec_remove_handlers(struct acpi_ec *ec)
749 {
750         if (ACPI_FAILURE(acpi_remove_address_space_handler(ec->handle,
751                                 ACPI_ADR_SPACE_EC, &acpi_ec_space_handler)))
752                 pr_err(PREFIX "failed to remove space handler\n");
753         if (ACPI_FAILURE(acpi_remove_gpe_handler(NULL, ec->gpe,
754                                 &acpi_ec_gpe_handler)))
755                 pr_err(PREFIX "failed to remove gpe handler\n");
756         ec->handlers_installed = 0;
757 }
758
759 static int acpi_ec_add(struct acpi_device *device)
760 {
761         struct acpi_ec *ec = NULL;
762
763         if (!device)
764                 return -EINVAL;
765         strcpy(acpi_device_name(device), ACPI_EC_DEVICE_NAME);
766         strcpy(acpi_device_class(device), ACPI_EC_CLASS);
767
768         /* Check for boot EC */
769         if (boot_ec) {
770                 if (boot_ec->handle == device->handle) {
771                         /* Pre-loaded EC from DSDT, just move pointer */
772                         ec = boot_ec;
773                         boot_ec = NULL;
774                         goto end;
775                 } else if (boot_ec->handle == ACPI_ROOT_OBJECT) {
776                         /* ECDT-based EC, time to shut it down */
777                         ec_remove_handlers(boot_ec);
778                         kfree(boot_ec);
779                         first_ec = boot_ec = NULL;
780                 }
781         }
782
783         ec = make_acpi_ec();
784         if (!ec)
785                 return -ENOMEM;
786
787         if (ec_parse_device(device->handle, 0, ec, NULL) !=
788             AE_CTRL_TERMINATE) {
789                 kfree(ec);
790                 return -EINVAL;
791         }
792         ec->handle = device->handle;
793       end:
794         if (!first_ec)
795                 first_ec = ec;
796         acpi_driver_data(device) = ec;
797         acpi_ec_add_fs(device);
798         pr_info(PREFIX "GPE = 0x%lx, I/O: command/status = 0x%lx, data = 0x%lx\n",
799                           ec->gpe, ec->command_addr, ec->data_addr);
800         pr_info(PREFIX "driver started in %s mode\n",
801                 (test_bit(EC_FLAGS_GPE_MODE, &ec->flags))?"interrupt":"poll");
802         return 0;
803 }
804
805 static int acpi_ec_remove(struct acpi_device *device, int type)
806 {
807         struct acpi_ec *ec;
808         struct acpi_ec_query_handler *handler, *tmp;
809
810         if (!device)
811                 return -EINVAL;
812
813         ec = acpi_driver_data(device);
814         mutex_lock(&ec->lock);
815         list_for_each_entry_safe(handler, tmp, &ec->list, node) {
816                 list_del(&handler->node);
817                 kfree(handler);
818         }
819         mutex_unlock(&ec->lock);
820         acpi_ec_remove_fs(device);
821         acpi_driver_data(device) = NULL;
822         if (ec == first_ec)
823                 first_ec = NULL;
824         kfree(ec);
825         return 0;
826 }
827
828 static acpi_status
829 ec_parse_io_ports(struct acpi_resource *resource, void *context)
830 {
831         struct acpi_ec *ec = context;
832
833         if (resource->type != ACPI_RESOURCE_TYPE_IO)
834                 return AE_OK;
835
836         /*
837          * The first address region returned is the data port, and
838          * the second address region returned is the status/command
839          * port.
840          */
841         if (ec->data_addr == 0)
842                 ec->data_addr = resource->data.io.minimum;
843         else if (ec->command_addr == 0)
844                 ec->command_addr = resource->data.io.minimum;
845         else
846                 return AE_CTRL_TERMINATE;
847
848         return AE_OK;
849 }
850
851 static int ec_install_handlers(struct acpi_ec *ec)
852 {
853         acpi_status status;
854         if (ec->handlers_installed)
855                 return 0;
856         status = acpi_install_gpe_handler(NULL, ec->gpe,
857                                           ACPI_GPE_EDGE_TRIGGERED,
858                                           &acpi_ec_gpe_handler, ec);
859         if (ACPI_FAILURE(status))
860                 return -ENODEV;
861
862         acpi_set_gpe_type(NULL, ec->gpe, ACPI_GPE_TYPE_RUNTIME);
863         acpi_enable_gpe(NULL, ec->gpe, ACPI_NOT_ISR);
864
865         status = acpi_install_address_space_handler(ec->handle,
866                                                     ACPI_ADR_SPACE_EC,
867                                                     &acpi_ec_space_handler,
868                                                     &acpi_ec_space_setup, ec);
869         if (ACPI_FAILURE(status)) {
870                 acpi_remove_gpe_handler(NULL, ec->gpe, &acpi_ec_gpe_handler);
871                 return -ENODEV;
872         }
873
874         ec->handlers_installed = 1;
875         return 0;
876 }
877
878 static int acpi_ec_start(struct acpi_device *device)
879 {
880         struct acpi_ec *ec;
881         int ret = 0;
882
883         if (!device)
884                 return -EINVAL;
885
886         ec = acpi_driver_data(device);
887
888         if (!ec)
889                 return -EINVAL;
890
891         ret = ec_install_handlers(ec);
892
893         /* EC is fully operational, allow queries */
894         clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags);
895         return ret;
896 }
897
898 static int acpi_ec_stop(struct acpi_device *device, int type)
899 {
900         struct acpi_ec *ec;
901         if (!device)
902                 return -EINVAL;
903         ec = acpi_driver_data(device);
904         if (!ec)
905                 return -EINVAL;
906         ec_remove_handlers(ec);
907
908         return 0;
909 }
910
911 int __init acpi_boot_ec_enable(void)
912 {
913         if (!boot_ec || boot_ec->handlers_installed)
914                 return 0;
915         if (!ec_install_handlers(boot_ec)) {
916                 first_ec = boot_ec;
917                 return 0;
918         }
919         return -EFAULT;
920 }
921
922 int __init acpi_ec_ecdt_probe(void)
923 {
924         int ret;
925         acpi_status status;
926         struct acpi_table_ecdt *ecdt_ptr;
927
928         boot_ec = make_acpi_ec();
929         if (!boot_ec)
930                 return -ENOMEM;
931         /*
932          * Generate a boot ec context
933          */
934         status = acpi_get_table(ACPI_SIG_ECDT, 1,
935                                 (struct acpi_table_header **)&ecdt_ptr);
936         if (ACPI_SUCCESS(status)) {
937                 pr_info(PREFIX "EC description table is found, configuring boot EC\n");
938                 boot_ec->command_addr = ecdt_ptr->control.address;
939                 boot_ec->data_addr = ecdt_ptr->data.address;
940                 boot_ec->gpe = ecdt_ptr->gpe;
941                 boot_ec->handle = ACPI_ROOT_OBJECT;
942         } else {
943                 /* This workaround is needed only on some broken machines,
944                  * which require early EC, but fail to provide ECDT */
945                 acpi_handle x;
946                 printk(KERN_DEBUG PREFIX "Look up EC in DSDT\n");
947                 status = acpi_get_devices(ec_device_ids[0].id, ec_parse_device,
948                                                 boot_ec, NULL);
949                 /* Check that acpi_get_devices actually find something */
950                 if (ACPI_FAILURE(status) || !boot_ec->handle)
951                         goto error;
952                 /* We really need to limit this workaround, the only ASUS,
953                  * which needs it, has fake EC._INI method, so use it as flag.
954                  * Keep boot_ec struct as it will be needed soon.
955                  */
956                 if (ACPI_FAILURE(acpi_get_handle(boot_ec->handle, "_INI", &x)))
957                         return -ENODEV;
958         }
959
960         ret = ec_install_handlers(boot_ec);
961         if (!ret) {
962                 first_ec = boot_ec;
963                 return 0;
964         }
965       error:
966         kfree(boot_ec);
967         boot_ec = NULL;
968         return -ENODEV;
969 }
970
971 static int __init acpi_ec_init(void)
972 {
973         int result = 0;
974
975         if (acpi_disabled)
976                 return 0;
977
978         acpi_ec_dir = proc_mkdir(ACPI_EC_CLASS, acpi_root_dir);
979         if (!acpi_ec_dir)
980                 return -ENODEV;
981
982         /* Now register the driver for the EC */
983         result = acpi_bus_register_driver(&acpi_ec_driver);
984         if (result < 0) {
985                 remove_proc_entry(ACPI_EC_CLASS, acpi_root_dir);
986                 return -ENODEV;
987         }
988
989         return result;
990 }
991
992 subsys_initcall(acpi_ec_init);
993
994 /* EC driver currently not unloadable */
995 #if 0
996 static void __exit acpi_ec_exit(void)
997 {
998
999         acpi_bus_unregister_driver(&acpi_ec_driver);
1000
1001         remove_proc_entry(ACPI_EC_CLASS, acpi_root_dir);
1002
1003         return;
1004 }
1005 #endif  /* 0 */