ACPICA: use new ACPI headers.
[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/sysdev.h>
33 #include <linux/kernel.h>
34 #include <linux/module.h>
35 #include <linux/init.h>
36 #include <linux/types.h>
37 #include <linux/proc_fs.h>
38 #include <linux/spinlock.h>
39 #include <linux/pm.h>
40 #include <linux/pci.h>
41 #include <linux/mutex.h>
42
43 #include <acpi/acpi_bus.h>
44 #include <acpi/acpi_drivers.h>
45
46 #define _COMPONENT              ACPI_PCI_COMPONENT
47 ACPI_MODULE_NAME("pci_link")
48 #define ACPI_PCI_LINK_CLASS             "pci_irq_routing"
49 #define ACPI_PCI_LINK_HID               "PNP0C0F"
50 #define ACPI_PCI_LINK_DRIVER_NAME       "ACPI PCI Interrupt Link Driver"
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 static int acpi_pci_link_add(struct acpi_device *device);
56 static int acpi_pci_link_remove(struct acpi_device *device, int type);
57
58 static struct acpi_driver acpi_pci_link_driver = {
59         .name = ACPI_PCI_LINK_DRIVER_NAME,
60         .class = ACPI_PCI_LINK_CLASS,
61         .ids = ACPI_PCI_LINK_HID,
62         .ops = {
63                 .add = acpi_pci_link_add,
64                 .remove = acpi_pci_link_remove,
65                 },
66 };
67
68 /*
69  * If a link is initialized, we never change its active and initialized
70  * later even the link is disable. Instead, we just repick the active irq
71  */
72 struct acpi_pci_link_irq {
73         u8 active;              /* Current IRQ */
74         u8 triggering;          /* All IRQs */
75         u8 polarity;    /* All IRQs */
76         u8 resource_type;
77         u8 possible_count;
78         u8 possible[ACPI_PCI_LINK_MAX_POSSIBLE];
79         u8 initialized:1;
80         u8 reserved:7;
81 };
82
83 struct acpi_pci_link {
84         struct list_head node;
85         struct acpi_device *device;
86         struct acpi_pci_link_irq irq;
87         int refcnt;
88 };
89
90 static struct {
91         int count;
92         struct list_head entries;
93 } acpi_link;
94 DEFINE_MUTEX(acpi_link_lock);
95
96 /* --------------------------------------------------------------------------
97                             PCI Link Device Management
98    -------------------------------------------------------------------------- */
99
100 /*
101  * set context (link) possible list from resource list
102  */
103 static acpi_status
104 acpi_pci_link_check_possible(struct acpi_resource *resource, void *context)
105 {
106         struct acpi_pci_link *link = context;
107         u32 i = 0;
108
109
110         switch (resource->type) {
111         case ACPI_RESOURCE_TYPE_START_DEPENDENT:
112                 return AE_OK;
113         case ACPI_RESOURCE_TYPE_IRQ:
114                 {
115                         struct acpi_resource_irq *p = &resource->data.irq;
116                         if (!p || !p->interrupt_count) {
117                                 printk(KERN_WARNING PREFIX "Blank IRQ resource\n");
118                                 return AE_OK;
119                         }
120                         for (i = 0;
121                              (i < p->interrupt_count
122                               && i < ACPI_PCI_LINK_MAX_POSSIBLE); i++) {
123                                 if (!p->interrupts[i]) {
124                                         printk(KERN_WARNING PREFIX "Invalid IRQ %d\n",
125                                                       p->interrupts[i]);
126                                         continue;
127                                 }
128                                 link->irq.possible[i] = p->interrupts[i];
129                                 link->irq.possible_count++;
130                         }
131                         link->irq.triggering = p->triggering;
132                         link->irq.polarity = p->polarity;
133                         link->irq.resource_type = ACPI_RESOURCE_TYPE_IRQ;
134                         break;
135                 }
136         case ACPI_RESOURCE_TYPE_EXTENDED_IRQ:
137                 {
138                         struct acpi_resource_extended_irq *p =
139                             &resource->data.extended_irq;
140                         if (!p || !p->interrupt_count) {
141                                 printk(KERN_WARNING PREFIX
142                                               "Blank EXT IRQ resource\n");
143                                 return AE_OK;
144                         }
145                         for (i = 0;
146                              (i < p->interrupt_count
147                               && i < ACPI_PCI_LINK_MAX_POSSIBLE); i++) {
148                                 if (!p->interrupts[i]) {
149                                         printk(KERN_WARNING PREFIX "Invalid IRQ %d\n",
150                                                       p->interrupts[i]);
151                                         continue;
152                                 }
153                                 link->irq.possible[i] = p->interrupts[i];
154                                 link->irq.possible_count++;
155                         }
156                         link->irq.triggering = p->triggering;
157                         link->irq.polarity = p->polarity;
158                         link->irq.resource_type = ACPI_RESOURCE_TYPE_EXTENDED_IRQ;
159                         break;
160                 }
161         default:
162                 printk(KERN_ERR PREFIX "Resource is not an IRQ entry\n");
163                 return AE_OK;
164         }
165
166         return AE_CTRL_TERMINATE;
167 }
168
169 static int acpi_pci_link_get_possible(struct acpi_pci_link *link)
170 {
171         acpi_status status;
172
173
174         if (!link)
175                 return -EINVAL;
176
177         status = acpi_walk_resources(link->device->handle, METHOD_NAME__PRS,
178                                      acpi_pci_link_check_possible, link);
179         if (ACPI_FAILURE(status)) {
180                 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PRS"));
181                 return -ENODEV;
182         }
183
184         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
185                           "Found %d possible IRQs\n",
186                           link->irq.possible_count));
187
188         return 0;
189 }
190
191 static acpi_status
192 acpi_pci_link_check_current(struct acpi_resource *resource, void *context)
193 {
194         int *irq = (int *)context;
195
196
197         switch (resource->type) {
198         case ACPI_RESOURCE_TYPE_IRQ:
199                 {
200                         struct acpi_resource_irq *p = &resource->data.irq;
201                         if (!p || !p->interrupt_count) {
202                                 /*
203                                  * IRQ descriptors may have no IRQ# bits set,
204                                  * particularly those those w/ _STA disabled
205                                  */
206                                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
207                                                   "Blank IRQ resource\n"));
208                                 return AE_OK;
209                         }
210                         *irq = p->interrupts[0];
211                         break;
212                 }
213         case ACPI_RESOURCE_TYPE_EXTENDED_IRQ:
214                 {
215                         struct acpi_resource_extended_irq *p =
216                             &resource->data.extended_irq;
217                         if (!p || !p->interrupt_count) {
218                                 /*
219                                  * extended IRQ descriptors must
220                                  * return at least 1 IRQ
221                                  */
222                                 printk(KERN_WARNING PREFIX
223                                               "Blank EXT IRQ resource\n");
224                                 return AE_OK;
225                         }
226                         *irq = p->interrupts[0];
227                         break;
228                 }
229                 break;
230         default:
231                 printk(KERN_ERR PREFIX "Resource %d isn't an IRQ\n", resource->type);
232         case ACPI_RESOURCE_TYPE_END_TAG:
233                 return AE_OK;
234         }
235         return AE_CTRL_TERMINATE;
236 }
237
238 /*
239  * Run _CRS and set link->irq.active
240  *
241  * return value:
242  * 0 - success
243  * !0 - failure
244  */
245 static int acpi_pci_link_get_current(struct acpi_pci_link *link)
246 {
247         int result = 0;
248         acpi_status status = AE_OK;
249         int irq = 0;
250
251         if (!link)
252                 return -EINVAL;
253
254         link->irq.active = 0;
255
256         /* in practice, status disabled is meaningless, ignore it */
257         if (acpi_strict) {
258                 /* Query _STA, set link->device->status */
259                 result = acpi_bus_get_status(link->device);
260                 if (result) {
261                         printk(KERN_ERR PREFIX "Unable to read status\n");
262                         goto end;
263                 }
264
265                 if (!link->device->status.enabled) {
266                         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Link disabled\n"));
267                         return 0;
268                 }
269         }
270
271         /* 
272          * Query and parse _CRS to get the current IRQ assignment. 
273          */
274
275         status = acpi_walk_resources(link->device->handle, METHOD_NAME__CRS,
276                                      acpi_pci_link_check_current, &irq);
277         if (ACPI_FAILURE(status)) {
278                 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _CRS"));
279                 result = -ENODEV;
280                 goto end;
281         }
282
283         if (acpi_strict && !irq) {
284                 printk(KERN_ERR PREFIX "_CRS returned 0\n");
285                 result = -ENODEV;
286         }
287
288         link->irq.active = irq;
289
290         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Link at IRQ %d \n", link->irq.active));
291
292       end:
293         return result;
294 }
295
296 static int acpi_pci_link_set(struct acpi_pci_link *link, int irq)
297 {
298         int result = 0;
299         acpi_status status = AE_OK;
300         struct {
301                 struct acpi_resource res;
302                 struct acpi_resource end;
303         } *resource;
304         struct acpi_buffer buffer = { 0, NULL };
305
306
307         if (!link || !irq)
308                 return -EINVAL;
309
310         resource = kzalloc(sizeof(*resource) + 1, irqs_disabled() ? GFP_ATOMIC: GFP_KERNEL);
311         if (!resource)
312                 return -ENOMEM;
313
314         buffer.length = sizeof(*resource) + 1;
315         buffer.pointer = resource;
316
317         switch (link->irq.resource_type) {
318         case ACPI_RESOURCE_TYPE_IRQ:
319                 resource->res.type = ACPI_RESOURCE_TYPE_IRQ;
320                 resource->res.length = sizeof(struct acpi_resource);
321                 resource->res.data.irq.triggering = link->irq.triggering;
322                 resource->res.data.irq.polarity =
323                     link->irq.polarity;
324                 if (link->irq.triggering == ACPI_EDGE_SENSITIVE)
325                         resource->res.data.irq.sharable =
326                             ACPI_EXCLUSIVE;
327                 else
328                         resource->res.data.irq.sharable = ACPI_SHARED;
329                 resource->res.data.irq.interrupt_count = 1;
330                 resource->res.data.irq.interrupts[0] = irq;
331                 break;
332
333         case ACPI_RESOURCE_TYPE_EXTENDED_IRQ:
334                 resource->res.type = ACPI_RESOURCE_TYPE_EXTENDED_IRQ;
335                 resource->res.length = sizeof(struct acpi_resource);
336                 resource->res.data.extended_irq.producer_consumer =
337                     ACPI_CONSUMER;
338                 resource->res.data.extended_irq.triggering =
339                     link->irq.triggering;
340                 resource->res.data.extended_irq.polarity =
341                     link->irq.polarity;
342                 if (link->irq.triggering == ACPI_EDGE_SENSITIVE)
343                         resource->res.data.irq.sharable =
344                             ACPI_EXCLUSIVE;
345                 else
346                         resource->res.data.irq.sharable = ACPI_SHARED;
347                 resource->res.data.extended_irq.interrupt_count = 1;
348                 resource->res.data.extended_irq.interrupts[0] = irq;
349                 /* ignore resource_source, it's optional */
350                 break;
351         default:
352                 printk(KERN_ERR PREFIX "Invalid Resource_type %d\n", link->irq.resource_type);
353                 result = -EINVAL;
354                 goto end;
355
356         }
357         resource->end.type = ACPI_RESOURCE_TYPE_END_TAG;
358
359         /* Attempt to set the resource */
360         status = acpi_set_current_resources(link->device->handle, &buffer);
361
362         /* check for total failure */
363         if (ACPI_FAILURE(status)) {
364                 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _SRS"));
365                 result = -ENODEV;
366                 goto end;
367         }
368
369         /* Query _STA, set device->status */
370         result = acpi_bus_get_status(link->device);
371         if (result) {
372                 printk(KERN_ERR PREFIX "Unable to read status\n");
373                 goto end;
374         }
375         if (!link->device->status.enabled) {
376                 printk(KERN_WARNING PREFIX
377                               "%s [%s] disabled and referenced, BIOS bug\n",
378                               acpi_device_name(link->device),
379                               acpi_device_bid(link->device));
380         }
381
382         /* Query _CRS, set link->irq.active */
383         result = acpi_pci_link_get_current(link);
384         if (result) {
385                 goto end;
386         }
387
388         /*
389          * Is current setting not what we set?
390          * set link->irq.active
391          */
392         if (link->irq.active != irq) {
393                 /*
394                  * policy: when _CRS doesn't return what we just _SRS
395                  * assume _SRS worked and override _CRS value.
396                  */
397                 printk(KERN_WARNING PREFIX
398                               "%s [%s] BIOS reported IRQ %d, using IRQ %d\n",
399                               acpi_device_name(link->device),
400                               acpi_device_bid(link->device), link->irq.active, irq);
401                 link->irq.active = irq;
402         }
403
404         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Set IRQ %d\n", link->irq.active));
405
406       end:
407         kfree(resource);
408         return result;
409 }
410
411 /* --------------------------------------------------------------------------
412                             PCI Link IRQ Management
413    -------------------------------------------------------------------------- */
414
415 /*
416  * "acpi_irq_balance" (default in APIC mode) enables ACPI to use PIC Interrupt
417  * Link Devices to move the PIRQs around to minimize sharing.
418  * 
419  * "acpi_irq_nobalance" (default in PIC mode) tells ACPI not to move any PIC IRQs
420  * that the BIOS has already set to active.  This is necessary because
421  * ACPI has no automatic means of knowing what ISA IRQs are used.  Note that
422  * if the BIOS doesn't set a Link Device active, ACPI needs to program it
423  * even if acpi_irq_nobalance is set.
424  *
425  * A tables of penalties avoids directing PCI interrupts to well known
426  * ISA IRQs. Boot params are available to over-ride the default table:
427  *
428  * List interrupts that are free for PCI use.
429  * acpi_irq_pci=n[,m]
430  *
431  * List interrupts that should not be used for PCI:
432  * acpi_irq_isa=n[,m]
433  *
434  * Note that PCI IRQ routers have a list of possible IRQs,
435  * which may not include the IRQs this table says are available.
436  * 
437  * Since this heuristic can't tell the difference between a link
438  * that no device will attach to, vs. a link which may be shared
439  * by multiple active devices -- it is not optimal.
440  *
441  * If interrupt performance is that important, get an IO-APIC system
442  * with a pin dedicated to each device.  Or for that matter, an MSI
443  * enabled system.
444  */
445
446 #define ACPI_MAX_IRQS           256
447 #define ACPI_MAX_ISA_IRQ        16
448
449 #define PIRQ_PENALTY_PCI_AVAILABLE      (0)
450 #define PIRQ_PENALTY_PCI_POSSIBLE       (16*16)
451 #define PIRQ_PENALTY_PCI_USING          (16*16*16)
452 #define PIRQ_PENALTY_ISA_TYPICAL        (16*16*16*16)
453 #define PIRQ_PENALTY_ISA_USED           (16*16*16*16*16)
454 #define PIRQ_PENALTY_ISA_ALWAYS         (16*16*16*16*16*16)
455
456 static int acpi_irq_penalty[ACPI_MAX_IRQS] = {
457         PIRQ_PENALTY_ISA_ALWAYS,        /* IRQ0 timer */
458         PIRQ_PENALTY_ISA_ALWAYS,        /* IRQ1 keyboard */
459         PIRQ_PENALTY_ISA_ALWAYS,        /* IRQ2 cascade */
460         PIRQ_PENALTY_ISA_TYPICAL,       /* IRQ3 serial */
461         PIRQ_PENALTY_ISA_TYPICAL,       /* IRQ4 serial */
462         PIRQ_PENALTY_ISA_TYPICAL,       /* IRQ5 sometimes SoundBlaster */
463         PIRQ_PENALTY_ISA_TYPICAL,       /* IRQ6 */
464         PIRQ_PENALTY_ISA_TYPICAL,       /* IRQ7 parallel, spurious */
465         PIRQ_PENALTY_ISA_TYPICAL,       /* IRQ8 rtc, sometimes */
466         PIRQ_PENALTY_PCI_AVAILABLE,     /* IRQ9  PCI, often acpi */
467         PIRQ_PENALTY_PCI_AVAILABLE,     /* IRQ10 PCI */
468         PIRQ_PENALTY_PCI_AVAILABLE,     /* IRQ11 PCI */
469         PIRQ_PENALTY_ISA_USED,  /* IRQ12 mouse */
470         PIRQ_PENALTY_ISA_USED,  /* IRQ13 fpe, sometimes */
471         PIRQ_PENALTY_ISA_USED,  /* IRQ14 ide0 */
472         PIRQ_PENALTY_ISA_USED,  /* IRQ15 ide1 */
473         /* >IRQ15 */
474 };
475
476 int __init acpi_irq_penalty_init(void)
477 {
478         struct list_head *node = NULL;
479         struct acpi_pci_link *link = NULL;
480         int i = 0;
481
482
483         /*
484          * Update penalties to facilitate IRQ balancing.
485          */
486         list_for_each(node, &acpi_link.entries) {
487
488                 link = list_entry(node, struct acpi_pci_link, node);
489                 if (!link) {
490                         printk(KERN_ERR PREFIX "Invalid link context\n");
491                         continue;
492                 }
493
494                 /*
495                  * reflect the possible and active irqs in the penalty table --
496                  * useful for breaking ties.
497                  */
498                 if (link->irq.possible_count) {
499                         int penalty =
500                             PIRQ_PENALTY_PCI_POSSIBLE /
501                             link->irq.possible_count;
502
503                         for (i = 0; i < link->irq.possible_count; i++) {
504                                 if (link->irq.possible[i] < ACPI_MAX_ISA_IRQ)
505                                         acpi_irq_penalty[link->irq.
506                                                          possible[i]] +=
507                                             penalty;
508                         }
509
510                 } else if (link->irq.active) {
511                         acpi_irq_penalty[link->irq.active] +=
512                             PIRQ_PENALTY_PCI_POSSIBLE;
513                 }
514         }
515         /* Add a penalty for the SCI */
516         acpi_irq_penalty[acpi_gbl_FADT.sci_interrupt] += PIRQ_PENALTY_PCI_USING;
517
518         return 0;
519 }
520
521 static int acpi_irq_balance;    /* 0: static, 1: balance */
522
523 static int acpi_pci_link_allocate(struct acpi_pci_link *link)
524 {
525         int irq;
526         int i;
527
528
529         if (link->irq.initialized) {
530                 if (link->refcnt == 0)
531                         /* This means the link is disabled but initialized */
532                         acpi_pci_link_set(link, link->irq.active);
533                 return 0;
534         }
535
536         /*
537          * search for active IRQ in list of possible IRQs.
538          */
539         for (i = 0; i < link->irq.possible_count; ++i) {
540                 if (link->irq.active == link->irq.possible[i])
541                         break;
542         }
543         /*
544          * forget active IRQ that is not in possible list
545          */
546         if (i == link->irq.possible_count) {
547                 if (acpi_strict)
548                         printk(KERN_WARNING PREFIX "_CRS %d not found"
549                                       " in _PRS\n", link->irq.active);
550                 link->irq.active = 0;
551         }
552
553         /*
554          * if active found, use it; else pick entry from end of possible list.
555          */
556         if (link->irq.active) {
557                 irq = link->irq.active;
558         } else {
559                 irq = link->irq.possible[link->irq.possible_count - 1];
560         }
561
562         if (acpi_irq_balance || !link->irq.active) {
563                 /*
564                  * Select the best IRQ.  This is done in reverse to promote
565                  * the use of IRQs 9, 10, 11, and >15.
566                  */
567                 for (i = (link->irq.possible_count - 1); i >= 0; i--) {
568                         if (acpi_irq_penalty[irq] >
569                             acpi_irq_penalty[link->irq.possible[i]])
570                                 irq = link->irq.possible[i];
571                 }
572         }
573
574         /* Attempt to enable the link device at this IRQ. */
575         if (acpi_pci_link_set(link, irq)) {
576                 printk(KERN_ERR PREFIX "Unable to set IRQ for %s [%s]. "
577                             "Try pci=noacpi or acpi=off\n",
578                             acpi_device_name(link->device),
579                             acpi_device_bid(link->device));
580                 return -ENODEV;
581         } else {
582                 acpi_irq_penalty[link->irq.active] += PIRQ_PENALTY_PCI_USING;
583                 printk(PREFIX "%s [%s] enabled at IRQ %d\n",
584                        acpi_device_name(link->device),
585                        acpi_device_bid(link->device), link->irq.active);
586         }
587
588         link->irq.initialized = 1;
589
590         return 0;
591 }
592
593 /*
594  * acpi_pci_link_allocate_irq
595  * success: return IRQ >= 0
596  * failure: return -1
597  */
598
599 int
600 acpi_pci_link_allocate_irq(acpi_handle handle,
601                            int index,
602                            int *triggering, int *polarity, char **name)
603 {
604         int result = 0;
605         struct acpi_device *device = NULL;
606         struct acpi_pci_link *link = NULL;
607
608
609         result = acpi_bus_get_device(handle, &device);
610         if (result) {
611                 printk(KERN_ERR PREFIX "Invalid link device\n");
612                 return -1;
613         }
614
615         link = acpi_driver_data(device);
616         if (!link) {
617                 printk(KERN_ERR PREFIX "Invalid link context\n");
618                 return -1;
619         }
620
621         /* TBD: Support multiple index (IRQ) entries per Link Device */
622         if (index) {
623                 printk(KERN_ERR PREFIX "Invalid index %d\n", index);
624                 return -1;
625         }
626
627         mutex_lock(&acpi_link_lock);
628         if (acpi_pci_link_allocate(link)) {
629                 mutex_unlock(&acpi_link_lock);
630                 return -1;
631         }
632
633         if (!link->irq.active) {
634                 mutex_unlock(&acpi_link_lock);
635                 printk(KERN_ERR PREFIX "Link active IRQ is 0!\n");
636                 return -1;
637         }
638         link->refcnt++;
639         mutex_unlock(&acpi_link_lock);
640
641         if (triggering)
642                 *triggering = link->irq.triggering;
643         if (polarity)
644                 *polarity = link->irq.polarity;
645         if (name)
646                 *name = acpi_device_bid(link->device);
647         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
648                           "Link %s is referenced\n",
649                           acpi_device_bid(link->device)));
650         return (link->irq.active);
651 }
652
653 /*
654  * We don't change link's irq information here.  After it is reenabled, we
655  * continue use the info
656  */
657 int acpi_pci_link_free_irq(acpi_handle handle)
658 {
659         struct acpi_device *device = NULL;
660         struct acpi_pci_link *link = NULL;
661         acpi_status result;
662
663
664         result = acpi_bus_get_device(handle, &device);
665         if (result) {
666                 printk(KERN_ERR PREFIX "Invalid link device\n");
667                 return -1;
668         }
669
670         link = acpi_driver_data(device);
671         if (!link) {
672                 printk(KERN_ERR PREFIX "Invalid link context\n");
673                 return -1;
674         }
675
676         mutex_lock(&acpi_link_lock);
677         if (!link->irq.initialized) {
678                 mutex_unlock(&acpi_link_lock);
679                 printk(KERN_ERR PREFIX "Link isn't initialized\n");
680                 return -1;
681         }
682 #ifdef  FUTURE_USE
683         /*
684          * The Link reference count allows us to _DISable an unused link
685          * and suspend time, and set it again  on resume.
686          * However, 2.6.12 still has irq_router.resume
687          * which blindly restores the link state.
688          * So we disable the reference count method
689          * to prevent duplicate acpi_pci_link_set()
690          * which would harm some systems
691          */
692         link->refcnt--;
693 #endif
694         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
695                           "Link %s is dereferenced\n",
696                           acpi_device_bid(link->device)));
697
698         if (link->refcnt == 0) {
699                 acpi_ut_evaluate_object(link->device->handle, "_DIS", 0, NULL);
700         }
701         mutex_unlock(&acpi_link_lock);
702         return (link->irq.active);
703 }
704
705 /* --------------------------------------------------------------------------
706                                  Driver Interface
707    -------------------------------------------------------------------------- */
708
709 static int acpi_pci_link_add(struct acpi_device *device)
710 {
711         int result = 0;
712         struct acpi_pci_link *link = NULL;
713         int i = 0;
714         int found = 0;
715
716
717         if (!device)
718                 return -EINVAL;
719
720         link = kzalloc(sizeof(struct acpi_pci_link), GFP_KERNEL);
721         if (!link)
722                 return -ENOMEM;
723
724         link->device = device;
725         strcpy(acpi_device_name(device), ACPI_PCI_LINK_DEVICE_NAME);
726         strcpy(acpi_device_class(device), ACPI_PCI_LINK_CLASS);
727         acpi_driver_data(device) = link;
728
729         mutex_lock(&acpi_link_lock);
730         result = acpi_pci_link_get_possible(link);
731         if (result)
732                 goto end;
733
734         /* query and set link->irq.active */
735         acpi_pci_link_get_current(link);
736
737         printk(PREFIX "%s [%s] (IRQs", acpi_device_name(device),
738                acpi_device_bid(device));
739         for (i = 0; i < link->irq.possible_count; i++) {
740                 if (link->irq.active == link->irq.possible[i]) {
741                         printk(" *%d", link->irq.possible[i]);
742                         found = 1;
743                 } else
744                         printk(" %d", link->irq.possible[i]);
745         }
746
747         printk(")");
748
749         if (!found)
750                 printk(" *%d", link->irq.active);
751
752         if (!link->device->status.enabled)
753                 printk(", disabled.");
754
755         printk("\n");
756
757         /* TBD: Acquire/release lock */
758         list_add_tail(&link->node, &acpi_link.entries);
759         acpi_link.count++;
760
761       end:
762         /* disable all links -- to be activated on use */
763         acpi_ut_evaluate_object(device->handle, "_DIS", 0, NULL);
764         mutex_unlock(&acpi_link_lock);
765
766         if (result)
767                 kfree(link);
768
769         return result;
770 }
771
772 static int acpi_pci_link_resume(struct acpi_pci_link *link)
773 {
774
775         if (link->refcnt && link->irq.active && link->irq.initialized)
776                 return (acpi_pci_link_set(link, link->irq.active));
777         else
778                 return 0;
779 }
780
781 static int irqrouter_resume(struct sys_device *dev)
782 {
783         struct list_head *node = NULL;
784         struct acpi_pci_link *link = NULL;
785
786
787         /* Make sure SCI is enabled again (Apple firmware bug?) */
788         acpi_set_register(ACPI_BITREG_SCI_ENABLE, 1);
789
790         list_for_each(node, &acpi_link.entries) {
791                 link = list_entry(node, struct acpi_pci_link, node);
792                 if (!link) {
793                         printk(KERN_ERR PREFIX "Invalid link context\n");
794                         continue;
795                 }
796                 acpi_pci_link_resume(link);
797         }
798         return 0;
799 }
800
801 static int acpi_pci_link_remove(struct acpi_device *device, int type)
802 {
803         struct acpi_pci_link *link = NULL;
804
805
806         if (!device || !acpi_driver_data(device))
807                 return -EINVAL;
808
809         link = acpi_driver_data(device);
810
811         mutex_lock(&acpi_link_lock);
812         list_del(&link->node);
813         mutex_unlock(&acpi_link_lock);
814
815         kfree(link);
816
817         return 0;
818 }
819
820 /*
821  * modify acpi_irq_penalty[] from cmdline
822  */
823 static int __init acpi_irq_penalty_update(char *str, int used)
824 {
825         int i;
826
827         for (i = 0; i < 16; i++) {
828                 int retval;
829                 int irq;
830
831                 retval = get_option(&str, &irq);
832
833                 if (!retval)
834                         break;  /* no number found */
835
836                 if (irq < 0)
837                         continue;
838
839                 if (irq >= ACPI_MAX_IRQS)
840                         continue;
841
842                 if (used)
843                         acpi_irq_penalty[irq] += PIRQ_PENALTY_ISA_USED;
844                 else
845                         acpi_irq_penalty[irq] = PIRQ_PENALTY_PCI_AVAILABLE;
846
847                 if (retval != 2)        /* no next number */
848                         break;
849         }
850         return 1;
851 }
852
853 /*
854  * We'd like PNP to call this routine for the
855  * single ISA_USED value for each legacy device.
856  * But instead it calls us with each POSSIBLE setting.
857  * There is no ISA_POSSIBLE weight, so we simply use
858  * the (small) PCI_USING penalty.
859  */
860 void acpi_penalize_isa_irq(int irq, int active)
861 {
862         if (active)
863                 acpi_irq_penalty[irq] += PIRQ_PENALTY_ISA_USED;
864         else
865                 acpi_irq_penalty[irq] += PIRQ_PENALTY_PCI_USING;
866 }
867
868 /*
869  * Over-ride default table to reserve additional IRQs for use by ISA
870  * e.g. acpi_irq_isa=5
871  * Useful for telling ACPI how not to interfere with your ISA sound card.
872  */
873 static int __init acpi_irq_isa(char *str)
874 {
875         return acpi_irq_penalty_update(str, 1);
876 }
877
878 __setup("acpi_irq_isa=", acpi_irq_isa);
879
880 /*
881  * Over-ride default table to free additional IRQs for use by PCI
882  * e.g. acpi_irq_pci=7,15
883  * Used for acpi_irq_balance to free up IRQs to reduce PCI IRQ sharing.
884  */
885 static int __init acpi_irq_pci(char *str)
886 {
887         return acpi_irq_penalty_update(str, 0);
888 }
889
890 __setup("acpi_irq_pci=", acpi_irq_pci);
891
892 static int __init acpi_irq_nobalance_set(char *str)
893 {
894         acpi_irq_balance = 0;
895         return 1;
896 }
897
898 __setup("acpi_irq_nobalance", acpi_irq_nobalance_set);
899
900 int __init acpi_irq_balance_set(char *str)
901 {
902         acpi_irq_balance = 1;
903         return 1;
904 }
905
906 __setup("acpi_irq_balance", acpi_irq_balance_set);
907
908 /* FIXME: we will remove this interface after all drivers call pci_disable_device */
909 static struct sysdev_class irqrouter_sysdev_class = {
910         set_kset_name("irqrouter"),
911         .resume = irqrouter_resume,
912 };
913
914 static struct sys_device device_irqrouter = {
915         .id = 0,
916         .cls = &irqrouter_sysdev_class,
917 };
918
919 static int __init irqrouter_init_sysfs(void)
920 {
921         int error;
922
923
924         if (acpi_disabled || acpi_noirq)
925                 return 0;
926
927         error = sysdev_class_register(&irqrouter_sysdev_class);
928         if (!error)
929                 error = sysdev_register(&device_irqrouter);
930
931         return error;
932 }
933
934 device_initcall(irqrouter_init_sysfs);
935
936 static int __init acpi_pci_link_init(void)
937 {
938
939         if (acpi_noirq)
940                 return 0;
941
942         acpi_link.count = 0;
943         INIT_LIST_HEAD(&acpi_link.entries);
944
945         if (acpi_bus_register_driver(&acpi_pci_link_driver) < 0)
946                 return -ENODEV;
947
948         return 0;
949 }
950
951 subsys_initcall(acpi_pci_link_init);