ACPI: EC: add another DMI check for ASUS hardware
[linux-2.6.git] / drivers / acpi / pci_link.c
1 /*
2  *  pci_link.c - ACPI PCI Interrupt Link Device Driver ($Revision: 34 $)
3  *
4  *  Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
5  *  Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
6  *  Copyright (C) 2002       Dominik Brodowski <devel@brodo.de>
7  *
8  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
9  *
10  *  This program is free software; you can redistribute it and/or modify
11  *  it under the terms of the GNU General Public License as published by
12  *  the Free Software Foundation; either version 2 of the License, or (at
13  *  your option) any later version.
14  *
15  *  This program is distributed in the hope that it will be useful, but
16  *  WITHOUT ANY WARRANTY; without even the implied warranty of
17  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
18  *  General Public License for more details.
19  *
20  *  You should have received a copy of the GNU General Public License along
21  *  with this program; if not, write to the Free Software Foundation, Inc.,
22  *  59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
23  *
24  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
25  *
26  * TBD: 
27  *      1. Support more than one IRQ resource entry per link device (index).
28  *      2. Implement start/stop mechanism and use ACPI Bus Driver facilities
29  *         for IRQ management (e.g. start()->_SRS).
30  */
31
32 #include <linux/syscore_ops.h>
33 #include <linux/kernel.h>
34 #include <linux/module.h>
35 #include <linux/init.h>
36 #include <linux/types.h>
37 #include <linux/spinlock.h>
38 #include <linux/pm.h>
39 #include <linux/pci.h>
40 #include <linux/mutex.h>
41 #include <linux/slab.h>
42
43 #include <acpi/acpi_bus.h>
44 #include <acpi/acpi_drivers.h>
45
46 #define PREFIX "ACPI: "
47
48 #define _COMPONENT                      ACPI_PCI_COMPONENT
49 ACPI_MODULE_NAME("pci_link");
50 #define ACPI_PCI_LINK_CLASS             "pci_irq_routing"
51 #define ACPI_PCI_LINK_DEVICE_NAME       "PCI Interrupt Link"
52 #define ACPI_PCI_LINK_FILE_INFO         "info"
53 #define ACPI_PCI_LINK_FILE_STATUS       "state"
54 #define ACPI_PCI_LINK_MAX_POSSIBLE      16
55
56 static int acpi_pci_link_add(struct acpi_device *device);
57 static int acpi_pci_link_remove(struct acpi_device *device, int type);
58
59 static const struct acpi_device_id link_device_ids[] = {
60         {"PNP0C0F", 0},
61         {"", 0},
62 };
63 MODULE_DEVICE_TABLE(acpi, link_device_ids);
64
65 static struct acpi_driver acpi_pci_link_driver = {
66         .name = "pci_link",
67         .class = ACPI_PCI_LINK_CLASS,
68         .ids = link_device_ids,
69         .ops = {
70                 .add = acpi_pci_link_add,
71                 .remove = acpi_pci_link_remove,
72         },
73 };
74
75 /*
76  * If a link is initialized, we never change its active and initialized
77  * later even the link is disable. Instead, we just repick the active irq
78  */
79 struct acpi_pci_link_irq {
80         u8 active;              /* Current IRQ */
81         u8 triggering;          /* All IRQs */
82         u8 polarity;            /* All IRQs */
83         u8 resource_type;
84         u8 possible_count;
85         u8 possible[ACPI_PCI_LINK_MAX_POSSIBLE];
86         u8 initialized:1;
87         u8 reserved:7;
88 };
89
90 struct acpi_pci_link {
91         struct list_head                list;
92         struct acpi_device              *device;
93         struct acpi_pci_link_irq        irq;
94         int                             refcnt;
95 };
96
97 static LIST_HEAD(acpi_link_list);
98 static DEFINE_MUTEX(acpi_link_lock);
99
100 /* --------------------------------------------------------------------------
101                             PCI Link Device Management
102    -------------------------------------------------------------------------- */
103
104 /*
105  * set context (link) possible list from resource list
106  */
107 static acpi_status acpi_pci_link_check_possible(struct acpi_resource *resource,
108                                                 void *context)
109 {
110         struct acpi_pci_link *link = context;
111         u32 i;
112
113         switch (resource->type) {
114         case ACPI_RESOURCE_TYPE_START_DEPENDENT:
115         case ACPI_RESOURCE_TYPE_END_TAG:
116                 return AE_OK;
117         case ACPI_RESOURCE_TYPE_IRQ:
118                 {
119                         struct acpi_resource_irq *p = &resource->data.irq;
120                         if (!p || !p->interrupt_count) {
121                                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
122                                                   "Blank _PRS IRQ resource\n"));
123                                 return AE_OK;
124                         }
125                         for (i = 0;
126                              (i < p->interrupt_count
127                               && i < ACPI_PCI_LINK_MAX_POSSIBLE); i++) {
128                                 if (!p->interrupts[i]) {
129                                         printk(KERN_WARNING PREFIX
130                                                "Invalid _PRS IRQ %d\n",
131                                                p->interrupts[i]);
132                                         continue;
133                                 }
134                                 link->irq.possible[i] = p->interrupts[i];
135                                 link->irq.possible_count++;
136                         }
137                         link->irq.triggering = p->triggering;
138                         link->irq.polarity = p->polarity;
139                         link->irq.resource_type = ACPI_RESOURCE_TYPE_IRQ;
140                         break;
141                 }
142         case ACPI_RESOURCE_TYPE_EXTENDED_IRQ:
143                 {
144                         struct acpi_resource_extended_irq *p =
145                             &resource->data.extended_irq;
146                         if (!p || !p->interrupt_count) {
147                                 printk(KERN_WARNING PREFIX
148                                               "Blank _PRS EXT IRQ resource\n");
149                                 return AE_OK;
150                         }
151                         for (i = 0;
152                              (i < p->interrupt_count
153                               && i < ACPI_PCI_LINK_MAX_POSSIBLE); i++) {
154                                 if (!p->interrupts[i]) {
155                                         printk(KERN_WARNING PREFIX
156                                                "Invalid _PRS IRQ %d\n",
157                                                p->interrupts[i]);
158                                         continue;
159                                 }
160                                 link->irq.possible[i] = p->interrupts[i];
161                                 link->irq.possible_count++;
162                         }
163                         link->irq.triggering = p->triggering;
164                         link->irq.polarity = p->polarity;
165                         link->irq.resource_type = ACPI_RESOURCE_TYPE_EXTENDED_IRQ;
166                         break;
167                 }
168         default:
169                 printk(KERN_ERR PREFIX "_PRS resource type 0x%x isn't an IRQ\n",
170                        resource->type);
171                 return AE_OK;
172         }
173
174         return AE_CTRL_TERMINATE;
175 }
176
177 static int acpi_pci_link_get_possible(struct acpi_pci_link *link)
178 {
179         acpi_status status;
180
181         status = acpi_walk_resources(link->device->handle, METHOD_NAME__PRS,
182                                      acpi_pci_link_check_possible, link);
183         if (ACPI_FAILURE(status)) {
184                 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PRS"));
185                 return -ENODEV;
186         }
187
188         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
189                           "Found %d possible IRQs\n",
190                           link->irq.possible_count));
191
192         return 0;
193 }
194
195 static acpi_status acpi_pci_link_check_current(struct acpi_resource *resource,
196                                                void *context)
197 {
198         int *irq = context;
199
200         switch (resource->type) {
201         case ACPI_RESOURCE_TYPE_START_DEPENDENT:
202         case ACPI_RESOURCE_TYPE_END_TAG:
203                 return AE_OK;
204         case ACPI_RESOURCE_TYPE_IRQ:
205                 {
206                         struct acpi_resource_irq *p = &resource->data.irq;
207                         if (!p || !p->interrupt_count) {
208                                 /*
209                                  * IRQ descriptors may have no IRQ# bits set,
210                                  * particularly those those w/ _STA disabled
211                                  */
212                                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
213                                                   "Blank _CRS IRQ resource\n"));
214                                 return AE_OK;
215                         }
216                         *irq = p->interrupts[0];
217                         break;
218                 }
219         case ACPI_RESOURCE_TYPE_EXTENDED_IRQ:
220                 {
221                         struct acpi_resource_extended_irq *p =
222                             &resource->data.extended_irq;
223                         if (!p || !p->interrupt_count) {
224                                 /*
225                                  * extended IRQ descriptors must
226                                  * return at least 1 IRQ
227                                  */
228                                 printk(KERN_WARNING PREFIX
229                                               "Blank _CRS EXT IRQ resource\n");
230                                 return AE_OK;
231                         }
232                         *irq = p->interrupts[0];
233                         break;
234                 }
235                 break;
236         default:
237                 printk(KERN_ERR PREFIX "_CRS resource type 0x%x isn't an IRQ\n",
238                        resource->type);
239                 return AE_OK;
240         }
241
242         return AE_CTRL_TERMINATE;
243 }
244
245 /*
246  * Run _CRS and set link->irq.active
247  *
248  * return value:
249  * 0 - success
250  * !0 - failure
251  */
252 static int acpi_pci_link_get_current(struct acpi_pci_link *link)
253 {
254         int result = 0;
255         acpi_status status;
256         int irq = 0;
257
258         link->irq.active = 0;
259
260         /* in practice, status disabled is meaningless, ignore it */
261         if (acpi_strict) {
262                 /* Query _STA, set link->device->status */
263                 result = acpi_bus_get_status(link->device);
264                 if (result) {
265                         printk(KERN_ERR PREFIX "Unable to read status\n");
266                         goto end;
267                 }
268
269                 if (!link->device->status.enabled) {
270                         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Link disabled\n"));
271                         return 0;
272                 }
273         }
274
275         /* 
276          * Query and parse _CRS to get the current IRQ assignment. 
277          */
278
279         status = acpi_walk_resources(link->device->handle, METHOD_NAME__CRS,
280                                      acpi_pci_link_check_current, &irq);
281         if (ACPI_FAILURE(status)) {
282                 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _CRS"));
283                 result = -ENODEV;
284                 goto end;
285         }
286
287         if (acpi_strict && !irq) {
288                 printk(KERN_ERR PREFIX "_CRS returned 0\n");
289                 result = -ENODEV;
290         }
291
292         link->irq.active = irq;
293
294         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Link at IRQ %d \n", link->irq.active));
295
296       end:
297         return result;
298 }
299
300 static int acpi_pci_link_set(struct acpi_pci_link *link, int irq)
301 {
302         int result;
303         acpi_status status;
304         struct {
305                 struct acpi_resource res;
306                 struct acpi_resource end;
307         } *resource;
308         struct acpi_buffer buffer = { 0, NULL };
309
310         if (!irq)
311                 return -EINVAL;
312
313         resource = kzalloc(sizeof(*resource) + 1, irqs_disabled() ? GFP_ATOMIC: GFP_KERNEL);
314         if (!resource)
315                 return -ENOMEM;
316
317         buffer.length = sizeof(*resource) + 1;
318         buffer.pointer = resource;
319
320         switch (link->irq.resource_type) {
321         case ACPI_RESOURCE_TYPE_IRQ:
322                 resource->res.type = ACPI_RESOURCE_TYPE_IRQ;
323                 resource->res.length = sizeof(struct acpi_resource);
324                 resource->res.data.irq.triggering = link->irq.triggering;
325                 resource->res.data.irq.polarity =
326                     link->irq.polarity;
327                 if (link->irq.triggering == ACPI_EDGE_SENSITIVE)
328                         resource->res.data.irq.sharable =
329                             ACPI_EXCLUSIVE;
330                 else
331                         resource->res.data.irq.sharable = ACPI_SHARED;
332                 resource->res.data.irq.interrupt_count = 1;
333                 resource->res.data.irq.interrupts[0] = irq;
334                 break;
335
336         case ACPI_RESOURCE_TYPE_EXTENDED_IRQ:
337                 resource->res.type = ACPI_RESOURCE_TYPE_EXTENDED_IRQ;
338                 resource->res.length = sizeof(struct acpi_resource);
339                 resource->res.data.extended_irq.producer_consumer =
340                     ACPI_CONSUMER;
341                 resource->res.data.extended_irq.triggering =
342                     link->irq.triggering;
343                 resource->res.data.extended_irq.polarity =
344                     link->irq.polarity;
345                 if (link->irq.triggering == ACPI_EDGE_SENSITIVE)
346                         resource->res.data.irq.sharable =
347                             ACPI_EXCLUSIVE;
348                 else
349                         resource->res.data.irq.sharable = ACPI_SHARED;
350                 resource->res.data.extended_irq.interrupt_count = 1;
351                 resource->res.data.extended_irq.interrupts[0] = irq;
352                 /* ignore resource_source, it's optional */
353                 break;
354         default:
355                 printk(KERN_ERR PREFIX "Invalid Resource_type %d\n", link->irq.resource_type);
356                 result = -EINVAL;
357                 goto end;
358
359         }
360         resource->end.type = ACPI_RESOURCE_TYPE_END_TAG;
361
362         /* Attempt to set the resource */
363         status = acpi_set_current_resources(link->device->handle, &buffer);
364
365         /* check for total failure */
366         if (ACPI_FAILURE(status)) {
367                 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _SRS"));
368                 result = -ENODEV;
369                 goto end;
370         }
371
372         /* Query _STA, set device->status */
373         result = acpi_bus_get_status(link->device);
374         if (result) {
375                 printk(KERN_ERR PREFIX "Unable to read status\n");
376                 goto end;
377         }
378         if (!link->device->status.enabled) {
379                 printk(KERN_WARNING PREFIX
380                               "%s [%s] disabled and referenced, BIOS bug\n",
381                               acpi_device_name(link->device),
382                               acpi_device_bid(link->device));
383         }
384
385         /* Query _CRS, set link->irq.active */
386         result = acpi_pci_link_get_current(link);
387         if (result) {
388                 goto end;
389         }
390
391         /*
392          * Is current setting not what we set?
393          * set link->irq.active
394          */
395         if (link->irq.active != irq) {
396                 /*
397                  * policy: when _CRS doesn't return what we just _SRS
398                  * assume _SRS worked and override _CRS value.
399                  */
400                 printk(KERN_WARNING PREFIX
401                               "%s [%s] BIOS reported IRQ %d, using IRQ %d\n",
402                               acpi_device_name(link->device),
403                               acpi_device_bid(link->device), link->irq.active, irq);
404                 link->irq.active = irq;
405         }
406
407         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Set IRQ %d\n", link->irq.active));
408
409       end:
410         kfree(resource);
411         return result;
412 }
413
414 /* --------------------------------------------------------------------------
415                             PCI Link IRQ Management
416    -------------------------------------------------------------------------- */
417
418 /*
419  * "acpi_irq_balance" (default in APIC mode) enables ACPI to use PIC Interrupt
420  * Link Devices to move the PIRQs around to minimize sharing.
421  * 
422  * "acpi_irq_nobalance" (default in PIC mode) tells ACPI not to move any PIC IRQs
423  * that the BIOS has already set to active.  This is necessary because
424  * ACPI has no automatic means of knowing what ISA IRQs are used.  Note that
425  * if the BIOS doesn't set a Link Device active, ACPI needs to program it
426  * even if acpi_irq_nobalance is set.
427  *
428  * A tables of penalties avoids directing PCI interrupts to well known
429  * ISA IRQs. Boot params are available to over-ride the default table:
430  *
431  * List interrupts that are free for PCI use.
432  * acpi_irq_pci=n[,m]
433  *
434  * List interrupts that should not be used for PCI:
435  * acpi_irq_isa=n[,m]
436  *
437  * Note that PCI IRQ routers have a list of possible IRQs,
438  * which may not include the IRQs this table says are available.
439  * 
440  * Since this heuristic can't tell the difference between a link
441  * that no device will attach to, vs. a link which may be shared
442  * by multiple active devices -- it is not optimal.
443  *
444  * If interrupt performance is that important, get an IO-APIC system
445  * with a pin dedicated to each device.  Or for that matter, an MSI
446  * enabled system.
447  */
448
449 #define ACPI_MAX_IRQS           256
450 #define ACPI_MAX_ISA_IRQ        16
451
452 #define PIRQ_PENALTY_PCI_AVAILABLE      (0)
453 #define PIRQ_PENALTY_PCI_POSSIBLE       (16*16)
454 #define PIRQ_PENALTY_PCI_USING          (16*16*16)
455 #define PIRQ_PENALTY_ISA_TYPICAL        (16*16*16*16)
456 #define PIRQ_PENALTY_ISA_USED           (16*16*16*16*16)
457 #define PIRQ_PENALTY_ISA_ALWAYS         (16*16*16*16*16*16)
458
459 static int acpi_irq_penalty[ACPI_MAX_IRQS] = {
460         PIRQ_PENALTY_ISA_ALWAYS,        /* IRQ0 timer */
461         PIRQ_PENALTY_ISA_ALWAYS,        /* IRQ1 keyboard */
462         PIRQ_PENALTY_ISA_ALWAYS,        /* IRQ2 cascade */
463         PIRQ_PENALTY_ISA_TYPICAL,       /* IRQ3 serial */
464         PIRQ_PENALTY_ISA_TYPICAL,       /* IRQ4 serial */
465         PIRQ_PENALTY_ISA_TYPICAL,       /* IRQ5 sometimes SoundBlaster */
466         PIRQ_PENALTY_ISA_TYPICAL,       /* IRQ6 */
467         PIRQ_PENALTY_ISA_TYPICAL,       /* IRQ7 parallel, spurious */
468         PIRQ_PENALTY_ISA_TYPICAL,       /* IRQ8 rtc, sometimes */
469         PIRQ_PENALTY_PCI_AVAILABLE,     /* IRQ9  PCI, often acpi */
470         PIRQ_PENALTY_PCI_AVAILABLE,     /* IRQ10 PCI */
471         PIRQ_PENALTY_PCI_AVAILABLE,     /* IRQ11 PCI */
472         PIRQ_PENALTY_ISA_USED,          /* IRQ12 mouse */
473         PIRQ_PENALTY_ISA_USED,          /* IRQ13 fpe, sometimes */
474         PIRQ_PENALTY_ISA_USED,          /* IRQ14 ide0 */
475         PIRQ_PENALTY_ISA_USED,          /* IRQ15 ide1 */
476         /* >IRQ15 */
477 };
478
479 int __init acpi_irq_penalty_init(void)
480 {
481         struct acpi_pci_link *link;
482         int i;
483
484         /*
485          * Update penalties to facilitate IRQ balancing.
486          */
487         list_for_each_entry(link, &acpi_link_list, list) {
488
489                 /*
490                  * reflect the possible and active irqs in the penalty table --
491                  * useful for breaking ties.
492                  */
493                 if (link->irq.possible_count) {
494                         int penalty =
495                             PIRQ_PENALTY_PCI_POSSIBLE /
496                             link->irq.possible_count;
497
498                         for (i = 0; i < link->irq.possible_count; i++) {
499                                 if (link->irq.possible[i] < ACPI_MAX_ISA_IRQ)
500                                         acpi_irq_penalty[link->irq.
501                                                          possible[i]] +=
502                                             penalty;
503                         }
504
505                 } else if (link->irq.active) {
506                         acpi_irq_penalty[link->irq.active] +=
507                             PIRQ_PENALTY_PCI_POSSIBLE;
508                 }
509         }
510         /* Add a penalty for the SCI */
511         acpi_irq_penalty[acpi_gbl_FADT.sci_interrupt] += PIRQ_PENALTY_PCI_USING;
512         return 0;
513 }
514
515 static int acpi_irq_balance = -1;       /* 0: static, 1: balance */
516
517 static int acpi_pci_link_allocate(struct acpi_pci_link *link)
518 {
519         int irq;
520         int i;
521
522         if (link->irq.initialized) {
523                 if (link->refcnt == 0)
524                         /* This means the link is disabled but initialized */
525                         acpi_pci_link_set(link, link->irq.active);
526                 return 0;
527         }
528
529         /*
530          * search for active IRQ in list of possible IRQs.
531          */
532         for (i = 0; i < link->irq.possible_count; ++i) {
533                 if (link->irq.active == link->irq.possible[i])
534                         break;
535         }
536         /*
537          * forget active IRQ that is not in possible list
538          */
539         if (i == link->irq.possible_count) {
540                 if (acpi_strict)
541                         printk(KERN_WARNING PREFIX "_CRS %d not found"
542                                       " in _PRS\n", link->irq.active);
543                 link->irq.active = 0;
544         }
545
546         /*
547          * if active found, use it; else pick entry from end of possible list.
548          */
549         if (link->irq.active)
550                 irq = link->irq.active;
551         else
552                 irq = link->irq.possible[link->irq.possible_count - 1];
553
554         if (acpi_irq_balance || !link->irq.active) {
555                 /*
556                  * Select the best IRQ.  This is done in reverse to promote
557                  * the use of IRQs 9, 10, 11, and >15.
558                  */
559                 for (i = (link->irq.possible_count - 1); i >= 0; i--) {
560                         if (acpi_irq_penalty[irq] >
561                             acpi_irq_penalty[link->irq.possible[i]])
562                                 irq = link->irq.possible[i];
563                 }
564         }
565
566         /* Attempt to enable the link device at this IRQ. */
567         if (acpi_pci_link_set(link, irq)) {
568                 printk(KERN_ERR PREFIX "Unable to set IRQ for %s [%s]. "
569                             "Try pci=noacpi or acpi=off\n",
570                             acpi_device_name(link->device),
571                             acpi_device_bid(link->device));
572                 return -ENODEV;
573         } else {
574                 acpi_irq_penalty[link->irq.active] += PIRQ_PENALTY_PCI_USING;
575                 printk(KERN_WARNING PREFIX "%s [%s] enabled at IRQ %d\n",
576                        acpi_device_name(link->device),
577                        acpi_device_bid(link->device), link->irq.active);
578         }
579
580         link->irq.initialized = 1;
581         return 0;
582 }
583
584 /*
585  * acpi_pci_link_allocate_irq
586  * success: return IRQ >= 0
587  * failure: return -1
588  */
589 int acpi_pci_link_allocate_irq(acpi_handle handle, int index, int *triggering,
590                                int *polarity, char **name)
591 {
592         int result;
593         struct acpi_device *device;
594         struct acpi_pci_link *link;
595
596         result = acpi_bus_get_device(handle, &device);
597         if (result) {
598                 printk(KERN_ERR PREFIX "Invalid link device\n");
599                 return -1;
600         }
601
602         link = acpi_driver_data(device);
603         if (!link) {
604                 printk(KERN_ERR PREFIX "Invalid link context\n");
605                 return -1;
606         }
607
608         /* TBD: Support multiple index (IRQ) entries per Link Device */
609         if (index) {
610                 printk(KERN_ERR PREFIX "Invalid index %d\n", index);
611                 return -1;
612         }
613
614         mutex_lock(&acpi_link_lock);
615         if (acpi_pci_link_allocate(link)) {
616                 mutex_unlock(&acpi_link_lock);
617                 return -1;
618         }
619
620         if (!link->irq.active) {
621                 mutex_unlock(&acpi_link_lock);
622                 printk(KERN_ERR PREFIX "Link active IRQ is 0!\n");
623                 return -1;
624         }
625         link->refcnt++;
626         mutex_unlock(&acpi_link_lock);
627
628         if (triggering)
629                 *triggering = link->irq.triggering;
630         if (polarity)
631                 *polarity = link->irq.polarity;
632         if (name)
633                 *name = acpi_device_bid(link->device);
634         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
635                           "Link %s is referenced\n",
636                           acpi_device_bid(link->device)));
637         return (link->irq.active);
638 }
639
640 /*
641  * We don't change link's irq information here.  After it is reenabled, we
642  * continue use the info
643  */
644 int acpi_pci_link_free_irq(acpi_handle handle)
645 {
646         struct acpi_device *device;
647         struct acpi_pci_link *link;
648         acpi_status result;
649
650         result = acpi_bus_get_device(handle, &device);
651         if (result) {
652                 printk(KERN_ERR PREFIX "Invalid link device\n");
653                 return -1;
654         }
655
656         link = acpi_driver_data(device);
657         if (!link) {
658                 printk(KERN_ERR PREFIX "Invalid link context\n");
659                 return -1;
660         }
661
662         mutex_lock(&acpi_link_lock);
663         if (!link->irq.initialized) {
664                 mutex_unlock(&acpi_link_lock);
665                 printk(KERN_ERR PREFIX "Link isn't initialized\n");
666                 return -1;
667         }
668 #ifdef  FUTURE_USE
669         /*
670          * The Link reference count allows us to _DISable an unused link
671          * and suspend time, and set it again  on resume.
672          * However, 2.6.12 still has irq_router.resume
673          * which blindly restores the link state.
674          * So we disable the reference count method
675          * to prevent duplicate acpi_pci_link_set()
676          * which would harm some systems
677          */
678         link->refcnt--;
679 #endif
680         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
681                           "Link %s is dereferenced\n",
682                           acpi_device_bid(link->device)));
683
684         if (link->refcnt == 0)
685                 acpi_evaluate_object(link->device->handle, "_DIS", NULL, NULL);
686
687         mutex_unlock(&acpi_link_lock);
688         return (link->irq.active);
689 }
690
691 /* --------------------------------------------------------------------------
692                                  Driver Interface
693    -------------------------------------------------------------------------- */
694
695 static int acpi_pci_link_add(struct acpi_device *device)
696 {
697         int result;
698         struct acpi_pci_link *link;
699         int i;
700         int found = 0;
701
702         link = kzalloc(sizeof(struct acpi_pci_link), GFP_KERNEL);
703         if (!link)
704                 return -ENOMEM;
705
706         link->device = device;
707         strcpy(acpi_device_name(device), ACPI_PCI_LINK_DEVICE_NAME);
708         strcpy(acpi_device_class(device), ACPI_PCI_LINK_CLASS);
709         device->driver_data = link;
710
711         mutex_lock(&acpi_link_lock);
712         result = acpi_pci_link_get_possible(link);
713         if (result)
714                 goto end;
715
716         /* query and set link->irq.active */
717         acpi_pci_link_get_current(link);
718
719         printk(KERN_INFO PREFIX "%s [%s] (IRQs", acpi_device_name(device),
720                acpi_device_bid(device));
721         for (i = 0; i < link->irq.possible_count; i++) {
722                 if (link->irq.active == link->irq.possible[i]) {
723                         printk(" *%d", link->irq.possible[i]);
724                         found = 1;
725                 } else
726                         printk(" %d", link->irq.possible[i]);
727         }
728
729         printk(")");
730
731         if (!found)
732                 printk(" *%d", link->irq.active);
733
734         if (!link->device->status.enabled)
735                 printk(", disabled.");
736
737         printk("\n");
738
739         list_add_tail(&link->list, &acpi_link_list);
740
741       end:
742         /* disable all links -- to be activated on use */
743         acpi_evaluate_object(device->handle, "_DIS", NULL, NULL);
744         mutex_unlock(&acpi_link_lock);
745
746         if (result)
747                 kfree(link);
748
749         return result;
750 }
751
752 static int acpi_pci_link_resume(struct acpi_pci_link *link)
753 {
754         if (link->refcnt && link->irq.active && link->irq.initialized)
755                 return (acpi_pci_link_set(link, link->irq.active));
756
757         return 0;
758 }
759
760 static void irqrouter_resume(void)
761 {
762         struct acpi_pci_link *link;
763
764         list_for_each_entry(link, &acpi_link_list, list) {
765                 acpi_pci_link_resume(link);
766         }
767 }
768
769 static int acpi_pci_link_remove(struct acpi_device *device, int type)
770 {
771         struct acpi_pci_link *link;
772
773         link = acpi_driver_data(device);
774
775         mutex_lock(&acpi_link_lock);
776         list_del(&link->list);
777         mutex_unlock(&acpi_link_lock);
778
779         kfree(link);
780         return 0;
781 }
782
783 /*
784  * modify acpi_irq_penalty[] from cmdline
785  */
786 static int __init acpi_irq_penalty_update(char *str, int used)
787 {
788         int i;
789
790         for (i = 0; i < 16; i++) {
791                 int retval;
792                 int irq;
793
794                 retval = get_option(&str, &irq);
795
796                 if (!retval)
797                         break;  /* no number found */
798
799                 if (irq < 0)
800                         continue;
801
802                 if (irq >= ARRAY_SIZE(acpi_irq_penalty))
803                         continue;
804
805                 if (used)
806                         acpi_irq_penalty[irq] += PIRQ_PENALTY_ISA_USED;
807                 else
808                         acpi_irq_penalty[irq] = PIRQ_PENALTY_PCI_AVAILABLE;
809
810                 if (retval != 2)        /* no next number */
811                         break;
812         }
813         return 1;
814 }
815
816 /*
817  * We'd like PNP to call this routine for the
818  * single ISA_USED value for each legacy device.
819  * But instead it calls us with each POSSIBLE setting.
820  * There is no ISA_POSSIBLE weight, so we simply use
821  * the (small) PCI_USING penalty.
822  */
823 void acpi_penalize_isa_irq(int irq, int active)
824 {
825         if (irq >= 0 && irq < ARRAY_SIZE(acpi_irq_penalty)) {
826                 if (active)
827                         acpi_irq_penalty[irq] += PIRQ_PENALTY_ISA_USED;
828                 else
829                         acpi_irq_penalty[irq] += PIRQ_PENALTY_PCI_USING;
830         }
831 }
832
833 /*
834  * Over-ride default table to reserve additional IRQs for use by ISA
835  * e.g. acpi_irq_isa=5
836  * Useful for telling ACPI how not to interfere with your ISA sound card.
837  */
838 static int __init acpi_irq_isa(char *str)
839 {
840         return acpi_irq_penalty_update(str, 1);
841 }
842
843 __setup("acpi_irq_isa=", acpi_irq_isa);
844
845 /*
846  * Over-ride default table to free additional IRQs for use by PCI
847  * e.g. acpi_irq_pci=7,15
848  * Used for acpi_irq_balance to free up IRQs to reduce PCI IRQ sharing.
849  */
850 static int __init acpi_irq_pci(char *str)
851 {
852         return acpi_irq_penalty_update(str, 0);
853 }
854
855 __setup("acpi_irq_pci=", acpi_irq_pci);
856
857 static int __init acpi_irq_nobalance_set(char *str)
858 {
859         acpi_irq_balance = 0;
860         return 1;
861 }
862
863 __setup("acpi_irq_nobalance", acpi_irq_nobalance_set);
864
865 static int __init acpi_irq_balance_set(char *str)
866 {
867         acpi_irq_balance = 1;
868         return 1;
869 }
870
871 __setup("acpi_irq_balance", acpi_irq_balance_set);
872
873 static struct syscore_ops irqrouter_syscore_ops = {
874         .resume = irqrouter_resume,
875 };
876
877 static int __init irqrouter_init_ops(void)
878 {
879         if (!acpi_disabled && !acpi_noirq)
880                 register_syscore_ops(&irqrouter_syscore_ops);
881
882         return 0;
883 }
884
885 device_initcall(irqrouter_init_ops);
886
887 static int __init acpi_pci_link_init(void)
888 {
889         if (acpi_noirq)
890                 return 0;
891
892         if (acpi_irq_balance == -1) {
893                 /* no command line switch: enable balancing in IOAPIC mode */
894                 if (acpi_irq_model == ACPI_IRQ_MODEL_IOAPIC)
895                         acpi_irq_balance = 1;
896                 else
897                         acpi_irq_balance = 0;
898         }
899
900         if (acpi_bus_register_driver(&acpi_pci_link_driver) < 0)
901                 return -ENODEV;
902
903         return 0;
904 }
905
906 subsys_initcall(acpi_pci_link_init);