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sched: prevent bound kthreads from changing cpus_allowed
[linux-2.6/mini2440.git] / drivers / acpi / ec.c
blob0924992187e87031809bf70c1b75c6367cc38a64
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 #define ACPI_EC_UDELAY 100 /* Wait 100us before polling EC again */
77
78 enum {
79 EC_FLAGS_WAIT_GPE = 0, /* Don't check status until GPE arrives */
80 EC_FLAGS_QUERY_PENDING, /* Query is pending */
81 EC_FLAGS_GPE_MODE, /* Expect GPE to be sent for status change */
82 EC_FLAGS_NO_GPE, /* Don't use GPE mode */
83 EC_FLAGS_RESCHEDULE_POLL /* Re-schedule poll */
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 static struct acpi_ec {
99 acpi_handle handle;
100 unsigned long gpe;
101 unsigned long command_addr;
102 unsigned long data_addr;
103 unsigned long global_lock;
104 unsigned long flags;
105 struct mutex lock;
106 wait_queue_head_t wait;
107 struct list_head list;
108 struct delayed_work work;
109 atomic_t irq_count;
110 u8 handlers_installed;
111 } *boot_ec, *first_ec;
112
113 /* --------------------------------------------------------------------------
114 Transaction Management
115 -------------------------------------------------------------------------- */
116
117 static inline u8 acpi_ec_read_status(struct acpi_ec *ec)
118 {
119 u8 x = inb(ec->command_addr);
120 pr_debug(PREFIX "---> status = 0x%2.2x\n", x);
121 return x;
122 }
123
124 static inline u8 acpi_ec_read_data(struct acpi_ec *ec)
125 {
126 u8 x = inb(ec->data_addr);
127 pr_debug(PREFIX "---> data = 0x%2.2x\n", x);
128 return inb(ec->data_addr);
129 }
130
131 static inline void acpi_ec_write_cmd(struct acpi_ec *ec, u8 command)
132 {
133 pr_debug(PREFIX "<--- command = 0x%2.2x\n", command);
134 outb(command, ec->command_addr);
135 }
136
137 static inline void acpi_ec_write_data(struct acpi_ec *ec, u8 data)
138 {
139 pr_debug(PREFIX "<--- data = 0x%2.2x\n", data);
140 outb(data, ec->data_addr);
141 }
142
143 static inline int acpi_ec_check_status(struct acpi_ec *ec, enum ec_event event)
144 {
145 if (test_bit(EC_FLAGS_WAIT_GPE, &ec->flags))
146 return 0;
147 if (event == ACPI_EC_EVENT_OBF_1) {
148 if (acpi_ec_read_status(ec) & ACPI_EC_FLAG_OBF)
149 return 1;
150 } else if (event == ACPI_EC_EVENT_IBF_0) {
151 if (!(acpi_ec_read_status(ec) & ACPI_EC_FLAG_IBF))
152 return 1;
153 }
154
155 return 0;
156 }
157
158 static void ec_schedule_ec_poll(struct acpi_ec *ec)
159 {
160 if (test_bit(EC_FLAGS_RESCHEDULE_POLL, &ec->flags))
161 schedule_delayed_work(&ec->work,
162 msecs_to_jiffies(ACPI_EC_DELAY));
163 }
164
165 static void ec_switch_to_poll_mode(struct acpi_ec *ec)
166 {
167 set_bit(EC_FLAGS_NO_GPE, &ec->flags);
168 clear_bit(EC_FLAGS_GPE_MODE, &ec->flags);
169 acpi_disable_gpe(NULL, ec->gpe, ACPI_NOT_ISR);
170 set_bit(EC_FLAGS_RESCHEDULE_POLL, &ec->flags);
171 }
172
173 static int acpi_ec_wait(struct acpi_ec *ec, enum ec_event event, int force_poll)
174 {
175 atomic_set(&ec->irq_count, 0);
176 if (likely(test_bit(EC_FLAGS_GPE_MODE, &ec->flags)) &&
177 likely(!force_poll)) {
178 if (wait_event_timeout(ec->wait, acpi_ec_check_status(ec, event),
179 msecs_to_jiffies(ACPI_EC_DELAY)))
180 return 0;
181 clear_bit(EC_FLAGS_WAIT_GPE, &ec->flags);
182 if (acpi_ec_check_status(ec, event)) {
183 /* missing GPEs, switch back to poll mode */
184 if (printk_ratelimit())
185 pr_info(PREFIX "missing confirmations, "
186 "switch off interrupt mode.\n");
187 ec_switch_to_poll_mode(ec);
188 ec_schedule_ec_poll(ec);
189 return 0;
190 }
191 } else {
192 unsigned long delay = jiffies + msecs_to_jiffies(ACPI_EC_DELAY);
193 clear_bit(EC_FLAGS_WAIT_GPE, &ec->flags);
194 while (time_before(jiffies, delay)) {
195 if (acpi_ec_check_status(ec, event))
196 return 0;
197 udelay(ACPI_EC_UDELAY);
198 }
199 }
200 pr_err(PREFIX "acpi_ec_wait timeout, status = 0x%2.2x, event = %s\n",
201 acpi_ec_read_status(ec),
202 (event == ACPI_EC_EVENT_OBF_1) ? "\"b0=1\"" : "\"b1=0\"");
203 return -ETIME;
204 }
205
206 static int acpi_ec_transaction_unlocked(struct acpi_ec *ec, u8 command,
207 const u8 * wdata, unsigned wdata_len,
208 u8 * rdata, unsigned rdata_len,
209 int force_poll)
210 {
211 int result = 0;
212 set_bit(EC_FLAGS_WAIT_GPE, &ec->flags);
213 pr_debug(PREFIX "transaction start\n");
214 acpi_ec_write_cmd(ec, command);
215 for (; wdata_len > 0; --wdata_len) {
216 result = acpi_ec_wait(ec, ACPI_EC_EVENT_IBF_0, force_poll);
217 if (result) {
218 pr_err(PREFIX
219 "write_cmd timeout, command = %d\n", command);
220 goto end;
221 }
222 set_bit(EC_FLAGS_WAIT_GPE, &ec->flags);
223 acpi_ec_write_data(ec, *(wdata++));
224 }
225
226 if (!rdata_len) {
227 result = acpi_ec_wait(ec, ACPI_EC_EVENT_IBF_0, force_poll);
228 if (result) {
229 pr_err(PREFIX
230 "finish-write timeout, command = %d\n", command);
231 goto end;
232 }
233 } else if (command == ACPI_EC_COMMAND_QUERY)
234 clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags);
235
236 for (; rdata_len > 0; --rdata_len) {
237 result = acpi_ec_wait(ec, ACPI_EC_EVENT_OBF_1, force_poll);
238 if (result) {
239 pr_err(PREFIX "read timeout, command = %d\n", command);
240 goto end;
241 }
242 /* Don't expect GPE after last read */
243 if (rdata_len > 1)
244 set_bit(EC_FLAGS_WAIT_GPE, &ec->flags);
245 *(rdata++) = acpi_ec_read_data(ec);
246 }
247 end:
248 pr_debug(PREFIX "transaction end\n");
249 return result;
250 }
251
252 static int acpi_ec_transaction(struct acpi_ec *ec, u8 command,
253 const u8 * wdata, unsigned wdata_len,
254 u8 * rdata, unsigned rdata_len,
255 int force_poll)
256 {
257 int status;
258 u32 glk;
259
260 if (!ec || (wdata_len && !wdata) || (rdata_len && !rdata))
261 return -EINVAL;
262
263 if (rdata)
264 memset(rdata, 0, rdata_len);
265
266 mutex_lock(&ec->lock);
267 if (ec->global_lock) {
268 status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk);
269 if (ACPI_FAILURE(status)) {
270 mutex_unlock(&ec->lock);
271 return -ENODEV;
272 }
273 }
274
275 status = acpi_ec_wait(ec, ACPI_EC_EVENT_IBF_0, 0);
276 if (status) {
277 pr_err(PREFIX "input buffer is not empty, "
278 "aborting transaction\n");
279 goto end;
280 }
281
282 status = acpi_ec_transaction_unlocked(ec, command,
283 wdata, wdata_len,
284 rdata, rdata_len,
285 force_poll);
286
287 end:
288
289 if (ec->global_lock)
290 acpi_release_global_lock(glk);
291 mutex_unlock(&ec->lock);
292
293 return status;
294 }
295
296 /*
297 * Note: samsung nv5000 doesn't work with ec burst mode.
298 * http://bugzilla.kernel.org/show_bug.cgi?id=4980
299 */
300 int acpi_ec_burst_enable(struct acpi_ec *ec)
301 {
302 u8 d;
303 return acpi_ec_transaction(ec, ACPI_EC_BURST_ENABLE, NULL, 0, &d, 1, 0);
304 }
305
306 int acpi_ec_burst_disable(struct acpi_ec *ec)
307 {
308 return acpi_ec_transaction(ec, ACPI_EC_BURST_DISABLE, NULL, 0, NULL, 0, 0);
309 }
310
311 static int acpi_ec_read(struct acpi_ec *ec, u8 address, u8 * data)
312 {
313 int result;
314 u8 d;
315
316 result = acpi_ec_transaction(ec, ACPI_EC_COMMAND_READ,
317 &address, 1, &d, 1, 0);
318 *data = d;
319 return result;
320 }
321
322 static int acpi_ec_write(struct acpi_ec *ec, u8 address, u8 data)
323 {
324 u8 wdata[2] = { address, data };
325 return acpi_ec_transaction(ec, ACPI_EC_COMMAND_WRITE,
326 wdata, 2, NULL, 0, 0);
327 }
328
329 /*
330 * Externally callable EC access functions. For now, assume 1 EC only
331 */
332 int ec_burst_enable(void)
333 {
334 if (!first_ec)
335 return -ENODEV;
336 return acpi_ec_burst_enable(first_ec);
337 }
338
339 EXPORT_SYMBOL(ec_burst_enable);
340
341 int ec_burst_disable(void)
342 {
343 if (!first_ec)
344 return -ENODEV;
345 return acpi_ec_burst_disable(first_ec);
346 }
347
348 EXPORT_SYMBOL(ec_burst_disable);
349
350 int ec_read(u8 addr, u8 * val)
351 {
352 int err;
353 u8 temp_data;
354
355 if (!first_ec)
356 return -ENODEV;
357
358 err = acpi_ec_read(first_ec, addr, &temp_data);
359
360 if (!err) {
361 *val = temp_data;
362 return 0;
363 } else
364 return err;
365 }
366
367 EXPORT_SYMBOL(ec_read);
368
369 int ec_write(u8 addr, u8 val)
370 {
371 int err;
372
373 if (!first_ec)
374 return -ENODEV;
375
376 err = acpi_ec_write(first_ec, addr, val);
377
378 return err;
379 }
380
381 EXPORT_SYMBOL(ec_write);
382
383 int ec_transaction(u8 command,
384 const u8 * wdata, unsigned wdata_len,
385 u8 * rdata, unsigned rdata_len,
386 int force_poll)
387 {
388 if (!first_ec)
389 return -ENODEV;
390
391 return acpi_ec_transaction(first_ec, command, wdata,
392 wdata_len, rdata, rdata_len,
393 force_poll);
394 }
395
396 EXPORT_SYMBOL(ec_transaction);
397
398 static int acpi_ec_query(struct acpi_ec *ec, u8 * data)
399 {
400 int result;
401 u8 d;
402
403 if (!ec || !data)
404 return -EINVAL;
405
406 /*
407 * Query the EC to find out which _Qxx method we need to evaluate.
408 * Note that successful completion of the query causes the ACPI_EC_SCI
409 * bit to be cleared (and thus clearing the interrupt source).
410 */
411
412 result = acpi_ec_transaction(ec, ACPI_EC_COMMAND_QUERY, NULL, 0, &d, 1, 0);
413 if (result)
414 return result;
415
416 if (!d)
417 return -ENODATA;
418
419 *data = d;
420 return 0;
421 }
422
423 /* --------------------------------------------------------------------------
424 Event Management
425 -------------------------------------------------------------------------- */
426 int acpi_ec_add_query_handler(struct acpi_ec *ec, u8 query_bit,
427 acpi_handle handle, acpi_ec_query_func func,
428 void *data)
429 {
430 struct acpi_ec_query_handler *handler =
431 kzalloc(sizeof(struct acpi_ec_query_handler), GFP_KERNEL);
432 if (!handler)
433 return -ENOMEM;
434
435 handler->query_bit = query_bit;
436 handler->handle = handle;
437 handler->func = func;
438 handler->data = data;
439 mutex_lock(&ec->lock);
440 list_add(&handler->node, &ec->list);
441 mutex_unlock(&ec->lock);
442 return 0;
443 }
444
445 EXPORT_SYMBOL_GPL(acpi_ec_add_query_handler);
446
447 void acpi_ec_remove_query_handler(struct acpi_ec *ec, u8 query_bit)
448 {
449 struct acpi_ec_query_handler *handler, *tmp;
450 mutex_lock(&ec->lock);
451 list_for_each_entry_safe(handler, tmp, &ec->list, node) {
452 if (query_bit == handler->query_bit) {
453 list_del(&handler->node);
454 kfree(handler);
455 }
456 }
457 mutex_unlock(&ec->lock);
458 }
459
460 EXPORT_SYMBOL_GPL(acpi_ec_remove_query_handler);
461
462 static void acpi_ec_gpe_query(void *ec_cxt)
463 {
464 struct acpi_ec *ec = ec_cxt;
465 u8 value = 0;
466 struct acpi_ec_query_handler *handler, copy;
467
468 if (!ec || acpi_ec_query(ec, &value))
469 return;
470 mutex_lock(&ec->lock);
471 list_for_each_entry(handler, &ec->list, node) {
472 if (value == handler->query_bit) {
473 /* have custom handler for this bit */
474 memcpy(&copy, handler, sizeof(copy));
475 mutex_unlock(&ec->lock);
476 if (copy.func) {
477 copy.func(copy.data);
478 } else if (copy.handle) {
479 acpi_evaluate_object(copy.handle, NULL, NULL, NULL);
480 }
481 return;
482 }
483 }
484 mutex_unlock(&ec->lock);
485 }
486
487 static u32 acpi_ec_gpe_handler(void *data)
488 {
489 acpi_status status = AE_OK;
490 struct acpi_ec *ec = data;
491 u8 state = acpi_ec_read_status(ec);
492
493 pr_debug(PREFIX "~~~> interrupt\n");
494 atomic_inc(&ec->irq_count);
495 if (atomic_read(&ec->irq_count) > 5) {
496 pr_err(PREFIX "GPE storm detected, disabling EC GPE\n");
497 ec_switch_to_poll_mode(ec);
498 goto end;
499 }
500 clear_bit(EC_FLAGS_WAIT_GPE, &ec->flags);
501 if (test_bit(EC_FLAGS_GPE_MODE, &ec->flags))
502 wake_up(&ec->wait);
503
504 if (state & ACPI_EC_FLAG_SCI) {
505 if (!test_and_set_bit(EC_FLAGS_QUERY_PENDING, &ec->flags))
506 status = acpi_os_execute(OSL_EC_BURST_HANDLER,
507 acpi_ec_gpe_query, ec);
508 } else if (!test_bit(EC_FLAGS_GPE_MODE, &ec->flags) &&
509 !test_bit(EC_FLAGS_NO_GPE, &ec->flags) &&
510 in_interrupt()) {
511 /* this is non-query, must be confirmation */
512 if (printk_ratelimit())
513 pr_info(PREFIX "non-query interrupt received,"
514 " switching to interrupt mode\n");
515 set_bit(EC_FLAGS_GPE_MODE, &ec->flags);
516 clear_bit(EC_FLAGS_RESCHEDULE_POLL, &ec->flags);
517 }
518 end:
519 ec_schedule_ec_poll(ec);
520 return ACPI_SUCCESS(status) ?
521 ACPI_INTERRUPT_HANDLED : ACPI_INTERRUPT_NOT_HANDLED;
522 }
523
524 static void do_ec_poll(struct work_struct *work)
525 {
526 struct acpi_ec *ec = container_of(work, struct acpi_ec, work.work);
527 atomic_set(&ec->irq_count, 0);
528 (void)acpi_ec_gpe_handler(ec);
529 }
530
531 /* --------------------------------------------------------------------------
532 Address Space Management
533 -------------------------------------------------------------------------- */
534
535 static acpi_status
536 acpi_ec_space_handler(u32 function, acpi_physical_address address,
537 u32 bits, acpi_integer *value,
538 void *handler_context, void *region_context)
539 {
540 struct acpi_ec *ec = handler_context;
541 int result = 0, i;
542 u8 temp = 0;
543
544 if ((address > 0xFF) || !value || !handler_context)
545 return AE_BAD_PARAMETER;
546
547 if (function != ACPI_READ && function != ACPI_WRITE)
548 return AE_BAD_PARAMETER;
549
550 if (bits != 8 && acpi_strict)
551 return AE_BAD_PARAMETER;
552
553 acpi_ec_burst_enable(ec);
554
555 if (function == ACPI_READ) {
556 result = acpi_ec_read(ec, address, &temp);
557 *value = temp;
558 } else {
559 temp = 0xff & (*value);
560 result = acpi_ec_write(ec, address, temp);
561 }
562
563 for (i = 8; unlikely(bits - i > 0); i += 8) {
564 ++address;
565 if (function == ACPI_READ) {
566 result = acpi_ec_read(ec, address, &temp);
567 (*value) |= ((acpi_integer)temp) << i;
568 } else {
569 temp = 0xff & ((*value) >> i);
570 result = acpi_ec_write(ec, address, temp);
571 }
572 }
573
574 acpi_ec_burst_disable(ec);
575
576 switch (result) {
577 case -EINVAL:
578 return AE_BAD_PARAMETER;
579 break;
580 case -ENODEV:
581 return AE_NOT_FOUND;
582 break;
583 case -ETIME:
584 return AE_TIME;
585 break;
586 default:
587 return AE_OK;
588 }
589 }
590
591 /* --------------------------------------------------------------------------
592 FS Interface (/proc)
593 -------------------------------------------------------------------------- */
594
595 static struct proc_dir_entry *acpi_ec_dir;
596
597 static int acpi_ec_read_info(struct seq_file *seq, void *offset)
598 {
599 struct acpi_ec *ec = seq->private;
600
601 if (!ec)
602 goto end;
603
604 seq_printf(seq, "gpe:\t\t\t0x%02x\n", (u32) ec->gpe);
605 seq_printf(seq, "ports:\t\t\t0x%02x, 0x%02x\n",
606 (unsigned)ec->command_addr, (unsigned)ec->data_addr);
607 seq_printf(seq, "use global lock:\t%s\n",
608 ec->global_lock ? "yes" : "no");
609 end:
610 return 0;
611 }
612
613 static int acpi_ec_info_open_fs(struct inode *inode, struct file *file)
614 {
615 return single_open(file, acpi_ec_read_info, PDE(inode)->data);
616 }
617
618 static struct file_operations acpi_ec_info_ops = {
619 .open = acpi_ec_info_open_fs,
620 .read = seq_read,
621 .llseek = seq_lseek,
622 .release = single_release,
623 .owner = THIS_MODULE,
624 };
625
626 static int acpi_ec_add_fs(struct acpi_device *device)
627 {
628 struct proc_dir_entry *entry = NULL;
629
630 if (!acpi_device_dir(device)) {
631 acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device),
632 acpi_ec_dir);
633 if (!acpi_device_dir(device))
634 return -ENODEV;
635 }
636
637 entry = proc_create_data(ACPI_EC_FILE_INFO, S_IRUGO,
638 acpi_device_dir(device),
639 &acpi_ec_info_ops, acpi_driver_data(device));
640 if (!entry)
641 return -ENODEV;
642 return 0;
643 }
644
645 static int acpi_ec_remove_fs(struct acpi_device *device)
646 {
647
648 if (acpi_device_dir(device)) {
649 remove_proc_entry(ACPI_EC_FILE_INFO, acpi_device_dir(device));
650 remove_proc_entry(acpi_device_bid(device), acpi_ec_dir);
651 acpi_device_dir(device) = NULL;
652 }
653
654 return 0;
655 }
656
657 /* --------------------------------------------------------------------------
658 Driver Interface
659 -------------------------------------------------------------------------- */
660 static acpi_status
661 ec_parse_io_ports(struct acpi_resource *resource, void *context);
662
663 static struct acpi_ec *make_acpi_ec(void)
664 {
665 struct acpi_ec *ec = kzalloc(sizeof(struct acpi_ec), GFP_KERNEL);
666 if (!ec)
667 return NULL;
668 ec->flags = 1 << EC_FLAGS_QUERY_PENDING;
669 mutex_init(&ec->lock);
670 init_waitqueue_head(&ec->wait);
671 INIT_LIST_HEAD(&ec->list);
672 INIT_DELAYED_WORK_DEFERRABLE(&ec->work, do_ec_poll);
673 atomic_set(&ec->irq_count, 0);
674 return ec;
675 }
676
677 static acpi_status
678 acpi_ec_register_query_methods(acpi_handle handle, u32 level,
679 void *context, void **return_value)
680 {
681 struct acpi_namespace_node *node = handle;
682 struct acpi_ec *ec = context;
683 int value = 0;
684 if (sscanf(node->name.ascii, "_Q%x", &value) == 1) {
685 acpi_ec_add_query_handler(ec, value, handle, NULL, NULL);
686 }
687 return AE_OK;
688 }
689
690 static acpi_status
691 ec_parse_device(acpi_handle handle, u32 Level, void *context, void **retval)
692 {
693 acpi_status status;
694
695 struct acpi_ec *ec = context;
696 status = acpi_walk_resources(handle, METHOD_NAME__CRS,
697 ec_parse_io_ports, ec);
698 if (ACPI_FAILURE(status))
699 return status;
700
701 /* Get GPE bit assignment (EC events). */
702 /* TODO: Add support for _GPE returning a package */
703 status = acpi_evaluate_integer(handle, "_GPE", NULL, &ec->gpe);
704 if (ACPI_FAILURE(status))
705 return status;
706 /* Use the global lock for all EC transactions? */
707 acpi_evaluate_integer(handle, "_GLK", NULL, &ec->global_lock);
708 ec->handle = handle;
709 return AE_CTRL_TERMINATE;
710 }
711
712 static void ec_poll_stop(struct acpi_ec *ec)
713 {
714 clear_bit(EC_FLAGS_RESCHEDULE_POLL, &ec->flags);
715 cancel_delayed_work(&ec->work);
716 }
717
718 static void ec_remove_handlers(struct acpi_ec *ec)
719 {
720 ec_poll_stop(ec);
721 if (ACPI_FAILURE(acpi_remove_address_space_handler(ec->handle,
722 ACPI_ADR_SPACE_EC, &acpi_ec_space_handler)))
723 pr_err(PREFIX "failed to remove space handler\n");
724 if (ACPI_FAILURE(acpi_remove_gpe_handler(NULL, ec->gpe,
725 &acpi_ec_gpe_handler)))
726 pr_err(PREFIX "failed to remove gpe handler\n");
727 ec->handlers_installed = 0;
728 }
729
730 static int acpi_ec_add(struct acpi_device *device)
731 {
732 struct acpi_ec *ec = NULL;
733
734 if (!device)
735 return -EINVAL;
736 strcpy(acpi_device_name(device), ACPI_EC_DEVICE_NAME);
737 strcpy(acpi_device_class(device), ACPI_EC_CLASS);
738
739 /* Check for boot EC */
740 if (boot_ec &&
741 (boot_ec->handle == device->handle ||
742 boot_ec->handle == ACPI_ROOT_OBJECT)) {
743 ec = boot_ec;
744 boot_ec = NULL;
745 } else {
746 ec = make_acpi_ec();
747 if (!ec)
748 return -ENOMEM;
749 if (ec_parse_device(device->handle, 0, ec, NULL) !=
750 AE_CTRL_TERMINATE) {
751 kfree(ec);
752 return -EINVAL;
753 }
754 }
755
756 ec->handle = device->handle;
757
758 /* Find and register all query methods */
759 acpi_walk_namespace(ACPI_TYPE_METHOD, ec->handle, 1,
760 acpi_ec_register_query_methods, ec, NULL);
761
762 if (!first_ec)
763 first_ec = ec;
764 acpi_driver_data(device) = ec;
765 acpi_ec_add_fs(device);
766 pr_info(PREFIX "GPE = 0x%lx, I/O: command/status = 0x%lx, data = 0x%lx\n",
767 ec->gpe, ec->command_addr, ec->data_addr);
768 pr_info(PREFIX "driver started in %s mode\n",
769 (test_bit(EC_FLAGS_GPE_MODE, &ec->flags))?"interrupt":"poll");
770 return 0;
771 }
772
773 static int acpi_ec_remove(struct acpi_device *device, int type)
774 {
775 struct acpi_ec *ec;
776 struct acpi_ec_query_handler *handler, *tmp;
777
778 if (!device)
779 return -EINVAL;
780
781 ec = acpi_driver_data(device);
782 mutex_lock(&ec->lock);
783 list_for_each_entry_safe(handler, tmp, &ec->list, node) {
784 list_del(&handler->node);
785 kfree(handler);
786 }
787 mutex_unlock(&ec->lock);
788 acpi_ec_remove_fs(device);
789 acpi_driver_data(device) = NULL;
790 if (ec == first_ec)
791 first_ec = NULL;
792 kfree(ec);
793 return 0;
794 }
795
796 static acpi_status
797 ec_parse_io_ports(struct acpi_resource *resource, void *context)
798 {
799 struct acpi_ec *ec = context;
800
801 if (resource->type != ACPI_RESOURCE_TYPE_IO)
802 return AE_OK;
803
804 /*
805 * The first address region returned is the data port, and
806 * the second address region returned is the status/command
807 * port.
808 */
809 if (ec->data_addr == 0)
810 ec->data_addr = resource->data.io.minimum;
811 else if (ec->command_addr == 0)
812 ec->command_addr = resource->data.io.minimum;
813 else
814 return AE_CTRL_TERMINATE;
815
816 return AE_OK;
817 }
818
819 static int ec_install_handlers(struct acpi_ec *ec)
820 {
821 acpi_status status;
822 if (ec->handlers_installed)
823 return 0;
824 status = acpi_install_gpe_handler(NULL, ec->gpe,
825 ACPI_GPE_EDGE_TRIGGERED,
826 &acpi_ec_gpe_handler, ec);
827 if (ACPI_FAILURE(status))
828 return -ENODEV;
829
830 acpi_set_gpe_type(NULL, ec->gpe, ACPI_GPE_TYPE_RUNTIME);
831 acpi_enable_gpe(NULL, ec->gpe, ACPI_NOT_ISR);
832
833 status = acpi_install_address_space_handler(ec->handle,
834 ACPI_ADR_SPACE_EC,
835 &acpi_ec_space_handler,
836 NULL, ec);
837 if (ACPI_FAILURE(status)) {
838 acpi_remove_gpe_handler(NULL, ec->gpe, &acpi_ec_gpe_handler);
839 return -ENODEV;
840 }
841
842 ec->handlers_installed = 1;
843 return 0;
844 }
845
846 static int acpi_ec_start(struct acpi_device *device)
847 {
848 struct acpi_ec *ec;
849 int ret = 0;
850
851 if (!device)
852 return -EINVAL;
853
854 ec = acpi_driver_data(device);
855
856 if (!ec)
857 return -EINVAL;
858
859 ret = ec_install_handlers(ec);
860
861 /* EC is fully operational, allow queries */
862 clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags);
863 ec_schedule_ec_poll(ec);
864 return ret;
865 }
866
867 static int acpi_ec_stop(struct acpi_device *device, int type)
868 {
869 struct acpi_ec *ec;
870 if (!device)
871 return -EINVAL;
872 ec = acpi_driver_data(device);
873 if (!ec)
874 return -EINVAL;
875 ec_remove_handlers(ec);
876
877 return 0;
878 }
879
880 int __init acpi_boot_ec_enable(void)
881 {
882 if (!boot_ec || boot_ec->handlers_installed)
883 return 0;
884 if (!ec_install_handlers(boot_ec)) {
885 first_ec = boot_ec;
886 return 0;
887 }
888 return -EFAULT;
889 }
890
891 static const struct acpi_device_id ec_device_ids[] = {
892 {"PNP0C09", 0},
893 {"", 0},
894 };
895
896 int __init acpi_ec_ecdt_probe(void)
897 {
898 int ret;
899 acpi_status status;
900 struct acpi_table_ecdt *ecdt_ptr;
901
902 boot_ec = make_acpi_ec();
903 if (!boot_ec)
904 return -ENOMEM;
905 /*
906 * Generate a boot ec context
907 */
908 status = acpi_get_table(ACPI_SIG_ECDT, 1,
909 (struct acpi_table_header **)&ecdt_ptr);
910 if (ACPI_SUCCESS(status)) {
911 pr_info(PREFIX "EC description table is found, configuring boot EC\n");
912 boot_ec->command_addr = ecdt_ptr->control.address;
913 boot_ec->data_addr = ecdt_ptr->data.address;
914 boot_ec->gpe = ecdt_ptr->gpe;
915 boot_ec->handle = ACPI_ROOT_OBJECT;
916 acpi_get_handle(ACPI_ROOT_OBJECT, ecdt_ptr->id, &boot_ec->handle);
917 } else {
918 /* This workaround is needed only on some broken machines,
919 * which require early EC, but fail to provide ECDT */
920 acpi_handle x;
921 printk(KERN_DEBUG PREFIX "Look up EC in DSDT\n");
922 status = acpi_get_devices(ec_device_ids[0].id, ec_parse_device,
923 boot_ec, NULL);
924 /* Check that acpi_get_devices actually find something */
925 if (ACPI_FAILURE(status) || !boot_ec->handle)
926 goto error;
927 /* We really need to limit this workaround, the only ASUS,
928 * which needs it, has fake EC._INI method, so use it as flag.
929 * Keep boot_ec struct as it will be needed soon.
930 */
931 if (ACPI_FAILURE(acpi_get_handle(boot_ec->handle, "_INI", &x)))
932 return -ENODEV;
933 }
934
935 ret = ec_install_handlers(boot_ec);
936 if (!ret) {
937 first_ec = boot_ec;
938 return 0;
939 }
940 error:
941 kfree(boot_ec);
942 boot_ec = NULL;
943 return -ENODEV;
944 }
945
946 static int acpi_ec_suspend(struct acpi_device *device, pm_message_t state)
947 {
948 struct acpi_ec *ec = acpi_driver_data(device);
949 /* Stop using GPE */
950 set_bit(EC_FLAGS_NO_GPE, &ec->flags);
951 clear_bit(EC_FLAGS_GPE_MODE, &ec->flags);
952 acpi_disable_gpe(NULL, ec->gpe, ACPI_NOT_ISR);
953 return 0;
954 }
955
956 static int acpi_ec_resume(struct acpi_device *device)
957 {
958 struct acpi_ec *ec = acpi_driver_data(device);
959 /* Enable use of GPE back */
960 clear_bit(EC_FLAGS_NO_GPE, &ec->flags);
961 acpi_enable_gpe(NULL, ec->gpe, ACPI_NOT_ISR);
962 return 0;
963 }
964
965 static struct acpi_driver acpi_ec_driver = {
966 .name = "ec",
967 .class = ACPI_EC_CLASS,
968 .ids = ec_device_ids,
969 .ops = {
970 .add = acpi_ec_add,
971 .remove = acpi_ec_remove,
972 .start = acpi_ec_start,
973 .stop = acpi_ec_stop,
974 .suspend = acpi_ec_suspend,
975 .resume = acpi_ec_resume,
976 },
977 };
978
979 static int __init acpi_ec_init(void)
980 {
981 int result = 0;
982
983 if (acpi_disabled)
984 return 0;
985
986 acpi_ec_dir = proc_mkdir(ACPI_EC_CLASS, acpi_root_dir);
987 if (!acpi_ec_dir)
988 return -ENODEV;
989
990 /* Now register the driver for the EC */
991 result = acpi_bus_register_driver(&acpi_ec_driver);
992 if (result < 0) {
993 remove_proc_entry(ACPI_EC_CLASS, acpi_root_dir);
994 return -ENODEV;
995 }
996
997 return result;
998 }
999
1000 subsys_initcall(acpi_ec_init);
1001
1002 /* EC driver currently not unloadable */
1003 #if 0
1004 static void __exit acpi_ec_exit(void)
1005 {
1006
1007 acpi_bus_unregister_driver(&acpi_ec_driver);
1008
1009 remove_proc_entry(ACPI_EC_CLASS, acpi_root_dir);
1010
1011 return;
1012 }
1013 #endif /* 0 */
Support for the Chinese Samsung S3C2440 based development boards