PCI Hotplug core: add 'name' param pci_hp_register interface
[safe/jmp/linux-2.6] / drivers / pci / hotplug / cpci_hotplug_core.c
1 /*
2  * CompactPCI Hot Plug Driver
3  *
4  * Copyright (C) 2002,2005 SOMA Networks, Inc.
5  * Copyright (C) 2001 Greg Kroah-Hartman (greg@kroah.com)
6  * Copyright (C) 2001 IBM Corp.
7  *
8  * All rights reserved.
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, GOOD TITLE or
18  * NON INFRINGEMENT.  See the GNU General Public License for more
19  * details.
20  *
21  * You should have received a copy of the GNU General Public License
22  * along with this program; if not, write to the Free Software
23  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
24  *
25  * Send feedback to <scottm@somanetworks.com>
26  */
27
28 #include <linux/module.h>
29 #include <linux/kernel.h>
30 #include <linux/slab.h>
31 #include <linux/pci.h>
32 #include <linux/pci_hotplug.h>
33 #include <linux/init.h>
34 #include <linux/interrupt.h>
35 #include <linux/smp_lock.h>
36 #include <asm/atomic.h>
37 #include <linux/delay.h>
38 #include <linux/kthread.h>
39 #include "cpci_hotplug.h"
40
41 #define DRIVER_AUTHOR   "Scott Murray <scottm@somanetworks.com>"
42 #define DRIVER_DESC     "CompactPCI Hot Plug Core"
43
44 #define MY_NAME "cpci_hotplug"
45
46 #define dbg(format, arg...)                                     \
47         do {                                                    \
48                 if (cpci_debug)                                 \
49                         printk (KERN_DEBUG "%s: " format "\n",  \
50                                 MY_NAME , ## arg);              \
51         } while (0)
52 #define err(format, arg...) printk(KERN_ERR "%s: " format "\n", MY_NAME , ## arg)
53 #define info(format, arg...) printk(KERN_INFO "%s: " format "\n", MY_NAME , ## arg)
54 #define warn(format, arg...) printk(KERN_WARNING "%s: " format "\n", MY_NAME , ## arg)
55
56 /* local variables */
57 static DECLARE_RWSEM(list_rwsem);
58 static LIST_HEAD(slot_list);
59 static int slots;
60 static atomic_t extracting;
61 int cpci_debug;
62 static struct cpci_hp_controller *controller;
63 static struct task_struct *cpci_thread;
64 static int thread_finished;
65
66 static int enable_slot(struct hotplug_slot *slot);
67 static int disable_slot(struct hotplug_slot *slot);
68 static int set_attention_status(struct hotplug_slot *slot, u8 value);
69 static int get_power_status(struct hotplug_slot *slot, u8 * value);
70 static int get_attention_status(struct hotplug_slot *slot, u8 * value);
71 static int get_adapter_status(struct hotplug_slot *slot, u8 * value);
72 static int get_latch_status(struct hotplug_slot *slot, u8 * value);
73
74 static struct hotplug_slot_ops cpci_hotplug_slot_ops = {
75         .owner = THIS_MODULE,
76         .enable_slot = enable_slot,
77         .disable_slot = disable_slot,
78         .set_attention_status = set_attention_status,
79         .get_power_status = get_power_status,
80         .get_attention_status = get_attention_status,
81         .get_adapter_status = get_adapter_status,
82         .get_latch_status = get_latch_status,
83 };
84
85 static int
86 update_latch_status(struct hotplug_slot *hotplug_slot, u8 value)
87 {
88         struct hotplug_slot_info info;
89
90         memcpy(&info, hotplug_slot->info, sizeof(struct hotplug_slot_info));
91         info.latch_status = value;
92         return pci_hp_change_slot_info(hotplug_slot, &info);
93 }
94
95 static int
96 update_adapter_status(struct hotplug_slot *hotplug_slot, u8 value)
97 {
98         struct hotplug_slot_info info;
99
100         memcpy(&info, hotplug_slot->info, sizeof(struct hotplug_slot_info));
101         info.adapter_status = value;
102         return pci_hp_change_slot_info(hotplug_slot, &info);
103 }
104
105 static int
106 enable_slot(struct hotplug_slot *hotplug_slot)
107 {
108         struct slot *slot = hotplug_slot->private;
109         int retval = 0;
110
111         dbg("%s - physical_slot = %s", __func__, hotplug_slot->name);
112
113         if (controller->ops->set_power)
114                 retval = controller->ops->set_power(slot, 1);
115         return retval;
116 }
117
118 static int
119 disable_slot(struct hotplug_slot *hotplug_slot)
120 {
121         struct slot *slot = hotplug_slot->private;
122         int retval = 0;
123
124         dbg("%s - physical_slot = %s", __func__, hotplug_slot->name);
125
126         down_write(&list_rwsem);
127
128         /* Unconfigure device */
129         dbg("%s - unconfiguring slot %s",
130             __func__, slot->hotplug_slot->name);
131         if ((retval = cpci_unconfigure_slot(slot))) {
132                 err("%s - could not unconfigure slot %s",
133                     __func__, slot->hotplug_slot->name);
134                 goto disable_error;
135         }
136         dbg("%s - finished unconfiguring slot %s",
137             __func__, slot->hotplug_slot->name);
138
139         /* Clear EXT (by setting it) */
140         if (cpci_clear_ext(slot)) {
141                 err("%s - could not clear EXT for slot %s",
142                     __func__, slot->hotplug_slot->name);
143                 retval = -ENODEV;
144                 goto disable_error;
145         }
146         cpci_led_on(slot);
147
148         if (controller->ops->set_power)
149                 if ((retval = controller->ops->set_power(slot, 0)))
150                         goto disable_error;
151
152         if (update_adapter_status(slot->hotplug_slot, 0))
153                 warn("failure to update adapter file");
154
155         if (slot->extracting) {
156                 slot->extracting = 0;
157                 atomic_dec(&extracting);
158         }
159 disable_error:
160         up_write(&list_rwsem);
161         return retval;
162 }
163
164 static u8
165 cpci_get_power_status(struct slot *slot)
166 {
167         u8 power = 1;
168
169         if (controller->ops->get_power)
170                 power = controller->ops->get_power(slot);
171         return power;
172 }
173
174 static int
175 get_power_status(struct hotplug_slot *hotplug_slot, u8 * value)
176 {
177         struct slot *slot = hotplug_slot->private;
178
179         *value = cpci_get_power_status(slot);
180         return 0;
181 }
182
183 static int
184 get_attention_status(struct hotplug_slot *hotplug_slot, u8 * value)
185 {
186         struct slot *slot = hotplug_slot->private;
187
188         *value = cpci_get_attention_status(slot);
189         return 0;
190 }
191
192 static int
193 set_attention_status(struct hotplug_slot *hotplug_slot, u8 status)
194 {
195         return cpci_set_attention_status(hotplug_slot->private, status);
196 }
197
198 static int
199 get_adapter_status(struct hotplug_slot *hotplug_slot, u8 * value)
200 {
201         *value = hotplug_slot->info->adapter_status;
202         return 0;
203 }
204
205 static int
206 get_latch_status(struct hotplug_slot *hotplug_slot, u8 * value)
207 {
208         *value = hotplug_slot->info->latch_status;
209         return 0;
210 }
211
212 static void release_slot(struct hotplug_slot *hotplug_slot)
213 {
214         struct slot *slot = hotplug_slot->private;
215
216         kfree(slot->hotplug_slot->info);
217         kfree(slot->hotplug_slot->name);
218         kfree(slot->hotplug_slot);
219         if (slot->dev)
220                 pci_dev_put(slot->dev);
221         kfree(slot);
222 }
223
224 #define SLOT_NAME_SIZE  6
225 static void
226 make_slot_name(struct slot *slot)
227 {
228         snprintf(slot->hotplug_slot->name,
229                  SLOT_NAME_SIZE, "%02x:%02x", slot->bus->number, slot->number);
230 }
231
232 int
233 cpci_hp_register_bus(struct pci_bus *bus, u8 first, u8 last)
234 {
235         struct slot *slot;
236         struct hotplug_slot *hotplug_slot;
237         struct hotplug_slot_info *info;
238         char *name;
239         int status = -ENOMEM;
240         int i;
241
242         if (!(controller && bus))
243                 return -ENODEV;
244
245         /*
246          * Create a structure for each slot, and register that slot
247          * with the pci_hotplug subsystem.
248          */
249         for (i = first; i <= last; ++i) {
250                 slot = kzalloc(sizeof (struct slot), GFP_KERNEL);
251                 if (!slot)
252                         goto error;
253
254                 hotplug_slot =
255                         kzalloc(sizeof (struct hotplug_slot), GFP_KERNEL);
256                 if (!hotplug_slot)
257                         goto error_slot;
258                 slot->hotplug_slot = hotplug_slot;
259
260                 info = kzalloc(sizeof (struct hotplug_slot_info), GFP_KERNEL);
261                 if (!info)
262                         goto error_hpslot;
263                 hotplug_slot->info = info;
264
265                 name = kmalloc(SLOT_NAME_SIZE, GFP_KERNEL);
266                 if (!name)
267                         goto error_info;
268                 hotplug_slot->name = name;
269
270                 slot->bus = bus;
271                 slot->number = i;
272                 slot->devfn = PCI_DEVFN(i, 0);
273
274                 hotplug_slot->private = slot;
275                 hotplug_slot->release = &release_slot;
276                 make_slot_name(slot);
277                 hotplug_slot->ops = &cpci_hotplug_slot_ops;
278
279                 /*
280                  * Initialize the slot info structure with some known
281                  * good values.
282                  */
283                 dbg("initializing slot %s", slot->hotplug_slot->name);
284                 info->power_status = cpci_get_power_status(slot);
285                 info->attention_status = cpci_get_attention_status(slot);
286
287                 dbg("registering slot %s", slot->hotplug_slot->name);
288                 status = pci_hp_register(slot->hotplug_slot, bus, i,
289                                          slot->hotplug_slot->name);
290                 if (status) {
291                         err("pci_hp_register failed with error %d", status);
292                         goto error_name;
293                 }
294
295                 /* Add slot to our internal list */
296                 down_write(&list_rwsem);
297                 list_add(&slot->slot_list, &slot_list);
298                 slots++;
299                 up_write(&list_rwsem);
300         }
301         return 0;
302 error_name:
303         kfree(name);
304 error_info:
305         kfree(info);
306 error_hpslot:
307         kfree(hotplug_slot);
308 error_slot:
309         kfree(slot);
310 error:
311         return status;
312 }
313
314 int
315 cpci_hp_unregister_bus(struct pci_bus *bus)
316 {
317         struct slot *slot;
318         struct slot *tmp;
319         int status = 0;
320
321         down_write(&list_rwsem);
322         if (!slots) {
323                 up_write(&list_rwsem);
324                 return -1;
325         }
326         list_for_each_entry_safe(slot, tmp, &slot_list, slot_list) {
327                 if (slot->bus == bus) {
328                         list_del(&slot->slot_list);
329                         slots--;
330
331                         dbg("deregistering slot %s", slot->hotplug_slot->name);
332                         status = pci_hp_deregister(slot->hotplug_slot);
333                         if (status) {
334                                 err("pci_hp_deregister failed with error %d",
335                                     status);
336                                 break;
337                         }
338                 }
339         }
340         up_write(&list_rwsem);
341         return status;
342 }
343
344 /* This is the interrupt mode interrupt handler */
345 static irqreturn_t
346 cpci_hp_intr(int irq, void *data)
347 {
348         dbg("entered cpci_hp_intr");
349
350         /* Check to see if it was our interrupt */
351         if ((controller->irq_flags & IRQF_SHARED) &&
352             !controller->ops->check_irq(controller->dev_id)) {
353                 dbg("exited cpci_hp_intr, not our interrupt");
354                 return IRQ_NONE;
355         }
356
357         /* Disable ENUM interrupt */
358         controller->ops->disable_irq();
359
360         /* Trigger processing by the event thread */
361         wake_up_process(cpci_thread);
362         return IRQ_HANDLED;
363 }
364
365 /*
366  * According to PICMG 2.1 R2.0, section 6.3.2, upon
367  * initialization, the system driver shall clear the
368  * INS bits of the cold-inserted devices.
369  */
370 static int
371 init_slots(int clear_ins)
372 {
373         struct slot *slot;
374         struct pci_dev* dev;
375
376         dbg("%s - enter", __func__);
377         down_read(&list_rwsem);
378         if (!slots) {
379                 up_read(&list_rwsem);
380                 return -1;
381         }
382         list_for_each_entry(slot, &slot_list, slot_list) {
383                 dbg("%s - looking at slot %s",
384                     __func__, slot->hotplug_slot->name);
385                 if (clear_ins && cpci_check_and_clear_ins(slot))
386                         dbg("%s - cleared INS for slot %s",
387                             __func__, slot->hotplug_slot->name);
388                 dev = pci_get_slot(slot->bus, PCI_DEVFN(slot->number, 0));
389                 if (dev) {
390                         if (update_adapter_status(slot->hotplug_slot, 1))
391                                 warn("failure to update adapter file");
392                         if (update_latch_status(slot->hotplug_slot, 1))
393                                 warn("failure to update latch file");
394                         slot->dev = dev;
395                 }
396         }
397         up_read(&list_rwsem);
398         dbg("%s - exit", __func__);
399         return 0;
400 }
401
402 static int
403 check_slots(void)
404 {
405         struct slot *slot;
406         int extracted;
407         int inserted;
408         u16 hs_csr;
409
410         down_read(&list_rwsem);
411         if (!slots) {
412                 up_read(&list_rwsem);
413                 err("no slots registered, shutting down");
414                 return -1;
415         }
416         extracted = inserted = 0;
417         list_for_each_entry(slot, &slot_list, slot_list) {
418                 dbg("%s - looking at slot %s",
419                     __func__, slot->hotplug_slot->name);
420                 if (cpci_check_and_clear_ins(slot)) {
421                         /*
422                          * Some broken hardware (e.g. PLX 9054AB) asserts
423                          * ENUM# twice...
424                          */
425                         if (slot->dev) {
426                                 warn("slot %s already inserted",
427                                      slot->hotplug_slot->name);
428                                 inserted++;
429                                 continue;
430                         }
431
432                         /* Process insertion */
433                         dbg("%s - slot %s inserted",
434                             __func__, slot->hotplug_slot->name);
435
436                         /* GSM, debug */
437                         hs_csr = cpci_get_hs_csr(slot);
438                         dbg("%s - slot %s HS_CSR (1) = %04x",
439                             __func__, slot->hotplug_slot->name, hs_csr);
440
441                         /* Configure device */
442                         dbg("%s - configuring slot %s",
443                             __func__, slot->hotplug_slot->name);
444                         if (cpci_configure_slot(slot)) {
445                                 err("%s - could not configure slot %s",
446                                     __func__, slot->hotplug_slot->name);
447                                 continue;
448                         }
449                         dbg("%s - finished configuring slot %s",
450                             __func__, slot->hotplug_slot->name);
451
452                         /* GSM, debug */
453                         hs_csr = cpci_get_hs_csr(slot);
454                         dbg("%s - slot %s HS_CSR (2) = %04x",
455                             __func__, slot->hotplug_slot->name, hs_csr);
456
457                         if (update_latch_status(slot->hotplug_slot, 1))
458                                 warn("failure to update latch file");
459
460                         if (update_adapter_status(slot->hotplug_slot, 1))
461                                 warn("failure to update adapter file");
462
463                         cpci_led_off(slot);
464
465                         /* GSM, debug */
466                         hs_csr = cpci_get_hs_csr(slot);
467                         dbg("%s - slot %s HS_CSR (3) = %04x",
468                             __func__, slot->hotplug_slot->name, hs_csr);
469
470                         inserted++;
471                 } else if (cpci_check_ext(slot)) {
472                         /* Process extraction request */
473                         dbg("%s - slot %s extracted",
474                             __func__, slot->hotplug_slot->name);
475
476                         /* GSM, debug */
477                         hs_csr = cpci_get_hs_csr(slot);
478                         dbg("%s - slot %s HS_CSR = %04x",
479                             __func__, slot->hotplug_slot->name, hs_csr);
480
481                         if (!slot->extracting) {
482                                 if (update_latch_status(slot->hotplug_slot, 0)) {
483                                         warn("failure to update latch file");
484                                 }
485                                 slot->extracting = 1;
486                                 atomic_inc(&extracting);
487                         }
488                         extracted++;
489                 } else if (slot->extracting) {
490                         hs_csr = cpci_get_hs_csr(slot);
491                         if (hs_csr == 0xffff) {
492                                 /*
493                                  * Hmmm, we're likely hosed at this point, should we
494                                  * bother trying to tell the driver or not?
495                                  */
496                                 err("card in slot %s was improperly removed",
497                                     slot->hotplug_slot->name);
498                                 if (update_adapter_status(slot->hotplug_slot, 0))
499                                         warn("failure to update adapter file");
500                                 slot->extracting = 0;
501                                 atomic_dec(&extracting);
502                         }
503                 }
504         }
505         up_read(&list_rwsem);
506         dbg("inserted=%d, extracted=%d, extracting=%d",
507             inserted, extracted, atomic_read(&extracting));
508         if (inserted || extracted)
509                 return extracted;
510         else if (!atomic_read(&extracting)) {
511                 err("cannot find ENUM# source, shutting down");
512                 return -1;
513         }
514         return 0;
515 }
516
517 /* This is the interrupt mode worker thread body */
518 static int
519 event_thread(void *data)
520 {
521         int rc;
522
523         dbg("%s - event thread started", __func__);
524         while (1) {
525                 dbg("event thread sleeping");
526                 set_current_state(TASK_INTERRUPTIBLE);
527                 schedule();
528                 if (kthread_should_stop())
529                         break;
530                 do {
531                         rc = check_slots();
532                         if (rc > 0) {
533                                 /* Give userspace a chance to handle extraction */
534                                 msleep(500);
535                         } else if (rc < 0) {
536                                 dbg("%s - error checking slots", __func__);
537                                 thread_finished = 1;
538                                 goto out;
539                         }
540                 } while (atomic_read(&extracting) && !kthread_should_stop());
541                 if (kthread_should_stop())
542                         break;
543
544                 /* Re-enable ENUM# interrupt */
545                 dbg("%s - re-enabling irq", __func__);
546                 controller->ops->enable_irq();
547         }
548  out:
549         return 0;
550 }
551
552 /* This is the polling mode worker thread body */
553 static int
554 poll_thread(void *data)
555 {
556         int rc;
557
558         while (1) {
559                 if (kthread_should_stop() || signal_pending(current))
560                         break;
561                 if (controller->ops->query_enum()) {
562                         do {
563                                 rc = check_slots();
564                                 if (rc > 0) {
565                                         /* Give userspace a chance to handle extraction */
566                                         msleep(500);
567                                 } else if (rc < 0) {
568                                         dbg("%s - error checking slots", __func__);
569                                         thread_finished = 1;
570                                         goto out;
571                                 }
572                         } while (atomic_read(&extracting) && !kthread_should_stop());
573                 }
574                 msleep(100);
575         }
576  out:
577         return 0;
578 }
579
580 static int
581 cpci_start_thread(void)
582 {
583         if (controller->irq)
584                 cpci_thread = kthread_run(event_thread, NULL, "cpci_hp_eventd");
585         else
586                 cpci_thread = kthread_run(poll_thread, NULL, "cpci_hp_polld");
587         if (IS_ERR(cpci_thread)) {
588                 err("Can't start up our thread");
589                 return PTR_ERR(cpci_thread);
590         }
591         thread_finished = 0;
592         return 0;
593 }
594
595 static void
596 cpci_stop_thread(void)
597 {
598         kthread_stop(cpci_thread);
599         thread_finished = 1;
600 }
601
602 int
603 cpci_hp_register_controller(struct cpci_hp_controller *new_controller)
604 {
605         int status = 0;
606
607         if (controller)
608                 return -1;
609         if (!(new_controller && new_controller->ops))
610                 return -EINVAL;
611         if (new_controller->irq) {
612                 if (!(new_controller->ops->enable_irq &&
613                      new_controller->ops->disable_irq))
614                         status = -EINVAL;
615                 if (request_irq(new_controller->irq,
616                                cpci_hp_intr,
617                                new_controller->irq_flags,
618                                MY_NAME,
619                                new_controller->dev_id)) {
620                         err("Can't get irq %d for the hotplug cPCI controller",
621                             new_controller->irq);
622                         status = -ENODEV;
623                 }
624                 dbg("%s - acquired controller irq %d",
625                     __func__, new_controller->irq);
626         }
627         if (!status)
628                 controller = new_controller;
629         return status;
630 }
631
632 static void
633 cleanup_slots(void)
634 {
635         struct slot *slot;
636         struct slot *tmp;
637
638         /*
639          * Unregister all of our slots with the pci_hotplug subsystem,
640          * and free up all memory that we had allocated.
641          */
642         down_write(&list_rwsem);
643         if (!slots)
644                 goto cleanup_null;
645         list_for_each_entry_safe(slot, tmp, &slot_list, slot_list) {
646                 list_del(&slot->slot_list);
647                 pci_hp_deregister(slot->hotplug_slot);
648         }
649 cleanup_null:
650         up_write(&list_rwsem);
651         return;
652 }
653
654 int
655 cpci_hp_unregister_controller(struct cpci_hp_controller *old_controller)
656 {
657         int status = 0;
658
659         if (controller) {
660                 if (!thread_finished)
661                         cpci_stop_thread();
662                 if (controller->irq)
663                         free_irq(controller->irq, controller->dev_id);
664                 controller = NULL;
665                 cleanup_slots();
666         } else
667                 status = -ENODEV;
668         return status;
669 }
670
671 int
672 cpci_hp_start(void)
673 {
674         static int first = 1;
675         int status;
676
677         dbg("%s - enter", __func__);
678         if (!controller)
679                 return -ENODEV;
680
681         down_read(&list_rwsem);
682         if (list_empty(&slot_list)) {
683                 up_read(&list_rwsem);
684                 return -ENODEV;
685         }
686         up_read(&list_rwsem);
687
688         status = init_slots(first);
689         if (first)
690                 first = 0;
691         if (status)
692                 return status;
693
694         status = cpci_start_thread();
695         if (status)
696                 return status;
697         dbg("%s - thread started", __func__);
698
699         if (controller->irq) {
700                 /* Start enum interrupt processing */
701                 dbg("%s - enabling irq", __func__);
702                 controller->ops->enable_irq();
703         }
704         dbg("%s - exit", __func__);
705         return 0;
706 }
707
708 int
709 cpci_hp_stop(void)
710 {
711         if (!controller)
712                 return -ENODEV;
713         if (controller->irq) {
714                 /* Stop enum interrupt processing */
715                 dbg("%s - disabling irq", __func__);
716                 controller->ops->disable_irq();
717         }
718         cpci_stop_thread();
719         return 0;
720 }
721
722 int __init
723 cpci_hotplug_init(int debug)
724 {
725         cpci_debug = debug;
726         return 0;
727 }
728
729 void __exit
730 cpci_hotplug_exit(void)
731 {
732         /*
733          * Clean everything up.
734          */
735         cpci_hp_stop();
736         cpci_hp_unregister_controller(controller);
737 }
738
739 EXPORT_SYMBOL_GPL(cpci_hp_register_controller);
740 EXPORT_SYMBOL_GPL(cpci_hp_unregister_controller);
741 EXPORT_SYMBOL_GPL(cpci_hp_register_bus);
742 EXPORT_SYMBOL_GPL(cpci_hp_unregister_bus);
743 EXPORT_SYMBOL_GPL(cpci_hp_start);
744 EXPORT_SYMBOL_GPL(cpci_hp_stop);