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[linux/fpc-iii.git] / drivers / pci / hotplug / cpci_hotplug_core.c
blob00c81a3cefc9be63e6bf47c5af9bdda0eefde37f
1 /*
2 * CompactPCI Hot Plug Driver
4 * Copyright (C) 2002,2005 SOMA Networks, Inc.
5 * Copyright (C) 2001 Greg Kroah-Hartman (greg@kroah.com)
6 * Copyright (C) 2001 IBM Corp.
8 * All rights reserved.
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.
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.
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.
25 * Send feedback to <scottm@somanetworks.com>
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/atomic.h>
36 #include <linux/delay.h>
37 #include <linux/kthread.h>
38 #include "cpci_hotplug.h"
40 #define DRIVER_AUTHOR "Scott Murray <scottm@somanetworks.com>"
41 #define DRIVER_DESC "CompactPCI Hot Plug Core"
43 #define MY_NAME "cpci_hotplug"
45 #define dbg(format, arg...) \
46 do { \
47 if (cpci_debug) \
48 printk (KERN_DEBUG "%s: " format "\n", \
49 MY_NAME , ## arg); \
50 } while (0)
51 #define err(format, arg...) printk(KERN_ERR "%s: " format "\n", MY_NAME , ## arg)
52 #define info(format, arg...) printk(KERN_INFO "%s: " format "\n", MY_NAME , ## arg)
53 #define warn(format, arg...) printk(KERN_WARNING "%s: " format "\n", MY_NAME , ## arg)
55 /* local variables */
56 static DECLARE_RWSEM(list_rwsem);
57 static LIST_HEAD(slot_list);
58 static int slots;
59 static atomic_t extracting;
60 int cpci_debug;
61 static struct cpci_hp_controller *controller;
62 static struct task_struct *cpci_thread;
63 static int thread_finished;
65 static int enable_slot(struct hotplug_slot *slot);
66 static int disable_slot(struct hotplug_slot *slot);
67 static int set_attention_status(struct hotplug_slot *slot, u8 value);
68 static int get_power_status(struct hotplug_slot *slot, u8 * value);
69 static int get_attention_status(struct hotplug_slot *slot, u8 * value);
70 static int get_adapter_status(struct hotplug_slot *slot, u8 * value);
71 static int get_latch_status(struct hotplug_slot *slot, u8 * value);
73 static struct hotplug_slot_ops cpci_hotplug_slot_ops = {
74 .enable_slot = enable_slot,
75 .disable_slot = disable_slot,
76 .set_attention_status = set_attention_status,
77 .get_power_status = get_power_status,
78 .get_attention_status = get_attention_status,
79 .get_adapter_status = get_adapter_status,
80 .get_latch_status = get_latch_status,
83 static int
84 update_latch_status(struct hotplug_slot *hotplug_slot, u8 value)
86 struct hotplug_slot_info info;
88 memcpy(&info, hotplug_slot->info, sizeof(struct hotplug_slot_info));
89 info.latch_status = value;
90 return pci_hp_change_slot_info(hotplug_slot, &info);
93 static int
94 update_adapter_status(struct hotplug_slot *hotplug_slot, u8 value)
96 struct hotplug_slot_info info;
98 memcpy(&info, hotplug_slot->info, sizeof(struct hotplug_slot_info));
99 info.adapter_status = value;
100 return pci_hp_change_slot_info(hotplug_slot, &info);
103 static int
104 enable_slot(struct hotplug_slot *hotplug_slot)
106 struct slot *slot = hotplug_slot->private;
107 int retval = 0;
109 dbg("%s - physical_slot = %s", __func__, slot_name(slot));
111 if (controller->ops->set_power)
112 retval = controller->ops->set_power(slot, 1);
113 return retval;
116 static int
117 disable_slot(struct hotplug_slot *hotplug_slot)
119 struct slot *slot = hotplug_slot->private;
120 int retval = 0;
122 dbg("%s - physical_slot = %s", __func__, slot_name(slot));
124 down_write(&list_rwsem);
126 /* Unconfigure device */
127 dbg("%s - unconfiguring slot %s", __func__, slot_name(slot));
128 if ((retval = cpci_unconfigure_slot(slot))) {
129 err("%s - could not unconfigure slot %s",
130 __func__, slot_name(slot));
131 goto disable_error;
133 dbg("%s - finished unconfiguring slot %s", __func__, slot_name(slot));
135 /* Clear EXT (by setting it) */
136 if (cpci_clear_ext(slot)) {
137 err("%s - could not clear EXT for slot %s",
138 __func__, slot_name(slot));
139 retval = -ENODEV;
140 goto disable_error;
142 cpci_led_on(slot);
144 if (controller->ops->set_power)
145 if ((retval = controller->ops->set_power(slot, 0)))
146 goto disable_error;
148 if (update_adapter_status(slot->hotplug_slot, 0))
149 warn("failure to update adapter file");
151 if (slot->extracting) {
152 slot->extracting = 0;
153 atomic_dec(&extracting);
155 disable_error:
156 up_write(&list_rwsem);
157 return retval;
160 static u8
161 cpci_get_power_status(struct slot *slot)
163 u8 power = 1;
165 if (controller->ops->get_power)
166 power = controller->ops->get_power(slot);
167 return power;
170 static int
171 get_power_status(struct hotplug_slot *hotplug_slot, u8 * value)
173 struct slot *slot = hotplug_slot->private;
175 *value = cpci_get_power_status(slot);
176 return 0;
179 static int
180 get_attention_status(struct hotplug_slot *hotplug_slot, u8 * value)
182 struct slot *slot = hotplug_slot->private;
184 *value = cpci_get_attention_status(slot);
185 return 0;
188 static int
189 set_attention_status(struct hotplug_slot *hotplug_slot, u8 status)
191 return cpci_set_attention_status(hotplug_slot->private, status);
194 static int
195 get_adapter_status(struct hotplug_slot *hotplug_slot, u8 * value)
197 *value = hotplug_slot->info->adapter_status;
198 return 0;
201 static int
202 get_latch_status(struct hotplug_slot *hotplug_slot, u8 * value)
204 *value = hotplug_slot->info->latch_status;
205 return 0;
208 static void release_slot(struct hotplug_slot *hotplug_slot)
210 struct slot *slot = hotplug_slot->private;
212 kfree(slot->hotplug_slot->info);
213 kfree(slot->hotplug_slot);
214 if (slot->dev)
215 pci_dev_put(slot->dev);
216 kfree(slot);
219 #define SLOT_NAME_SIZE 6
222 cpci_hp_register_bus(struct pci_bus *bus, u8 first, u8 last)
224 struct slot *slot;
225 struct hotplug_slot *hotplug_slot;
226 struct hotplug_slot_info *info;
227 char name[SLOT_NAME_SIZE];
228 int status;
229 int i;
231 if (!(controller && bus))
232 return -ENODEV;
235 * Create a structure for each slot, and register that slot
236 * with the pci_hotplug subsystem.
238 for (i = first; i <= last; ++i) {
239 slot = kzalloc(sizeof (struct slot), GFP_KERNEL);
240 if (!slot) {
241 status = -ENOMEM;
242 goto error;
245 hotplug_slot =
246 kzalloc(sizeof (struct hotplug_slot), GFP_KERNEL);
247 if (!hotplug_slot) {
248 status = -ENOMEM;
249 goto error_slot;
251 slot->hotplug_slot = hotplug_slot;
253 info = kzalloc(sizeof (struct hotplug_slot_info), GFP_KERNEL);
254 if (!info) {
255 status = -ENOMEM;
256 goto error_hpslot;
258 hotplug_slot->info = info;
260 slot->bus = bus;
261 slot->number = i;
262 slot->devfn = PCI_DEVFN(i, 0);
264 snprintf(name, SLOT_NAME_SIZE, "%02x:%02x", bus->number, i);
266 hotplug_slot->private = slot;
267 hotplug_slot->release = &release_slot;
268 hotplug_slot->ops = &cpci_hotplug_slot_ops;
271 * Initialize the slot info structure with some known
272 * good values.
274 dbg("initializing slot %s", name);
275 info->power_status = cpci_get_power_status(slot);
276 info->attention_status = cpci_get_attention_status(slot);
278 dbg("registering slot %s", name);
279 status = pci_hp_register(slot->hotplug_slot, bus, i, name);
280 if (status) {
281 err("pci_hp_register failed with error %d", status);
282 goto error_info;
284 dbg("slot registered with name: %s", slot_name(slot));
286 /* Add slot to our internal list */
287 down_write(&list_rwsem);
288 list_add(&slot->slot_list, &slot_list);
289 slots++;
290 up_write(&list_rwsem);
292 return 0;
293 error_info:
294 kfree(info);
295 error_hpslot:
296 kfree(hotplug_slot);
297 error_slot:
298 kfree(slot);
299 error:
300 return status;
304 cpci_hp_unregister_bus(struct pci_bus *bus)
306 struct slot *slot;
307 struct slot *tmp;
308 int status = 0;
310 down_write(&list_rwsem);
311 if (!slots) {
312 up_write(&list_rwsem);
313 return -1;
315 list_for_each_entry_safe(slot, tmp, &slot_list, slot_list) {
316 if (slot->bus == bus) {
317 list_del(&slot->slot_list);
318 slots--;
320 dbg("deregistering slot %s", slot_name(slot));
321 status = pci_hp_deregister(slot->hotplug_slot);
322 if (status) {
323 err("pci_hp_deregister failed with error %d",
324 status);
325 break;
329 up_write(&list_rwsem);
330 return status;
333 /* This is the interrupt mode interrupt handler */
334 static irqreturn_t
335 cpci_hp_intr(int irq, void *data)
337 dbg("entered cpci_hp_intr");
339 /* Check to see if it was our interrupt */
340 if ((controller->irq_flags & IRQF_SHARED) &&
341 !controller->ops->check_irq(controller->dev_id)) {
342 dbg("exited cpci_hp_intr, not our interrupt");
343 return IRQ_NONE;
346 /* Disable ENUM interrupt */
347 controller->ops->disable_irq();
349 /* Trigger processing by the event thread */
350 wake_up_process(cpci_thread);
351 return IRQ_HANDLED;
355 * According to PICMG 2.1 R2.0, section 6.3.2, upon
356 * initialization, the system driver shall clear the
357 * INS bits of the cold-inserted devices.
359 static int
360 init_slots(int clear_ins)
362 struct slot *slot;
363 struct pci_dev* dev;
365 dbg("%s - enter", __func__);
366 down_read(&list_rwsem);
367 if (!slots) {
368 up_read(&list_rwsem);
369 return -1;
371 list_for_each_entry(slot, &slot_list, slot_list) {
372 dbg("%s - looking at slot %s", __func__, slot_name(slot));
373 if (clear_ins && cpci_check_and_clear_ins(slot))
374 dbg("%s - cleared INS for slot %s",
375 __func__, slot_name(slot));
376 dev = pci_get_slot(slot->bus, PCI_DEVFN(slot->number, 0));
377 if (dev) {
378 if (update_adapter_status(slot->hotplug_slot, 1))
379 warn("failure to update adapter file");
380 if (update_latch_status(slot->hotplug_slot, 1))
381 warn("failure to update latch file");
382 slot->dev = dev;
385 up_read(&list_rwsem);
386 dbg("%s - exit", __func__);
387 return 0;
390 static int
391 check_slots(void)
393 struct slot *slot;
394 int extracted;
395 int inserted;
396 u16 hs_csr;
398 down_read(&list_rwsem);
399 if (!slots) {
400 up_read(&list_rwsem);
401 err("no slots registered, shutting down");
402 return -1;
404 extracted = inserted = 0;
405 list_for_each_entry(slot, &slot_list, slot_list) {
406 dbg("%s - looking at slot %s", __func__, slot_name(slot));
407 if (cpci_check_and_clear_ins(slot)) {
409 * Some broken hardware (e.g. PLX 9054AB) asserts
410 * ENUM# twice...
412 if (slot->dev) {
413 warn("slot %s already inserted",
414 slot_name(slot));
415 inserted++;
416 continue;
419 /* Process insertion */
420 dbg("%s - slot %s inserted", __func__, slot_name(slot));
422 /* GSM, debug */
423 hs_csr = cpci_get_hs_csr(slot);
424 dbg("%s - slot %s HS_CSR (1) = %04x",
425 __func__, slot_name(slot), hs_csr);
427 /* Configure device */
428 dbg("%s - configuring slot %s",
429 __func__, slot_name(slot));
430 if (cpci_configure_slot(slot)) {
431 err("%s - could not configure slot %s",
432 __func__, slot_name(slot));
433 continue;
435 dbg("%s - finished configuring slot %s",
436 __func__, slot_name(slot));
438 /* GSM, debug */
439 hs_csr = cpci_get_hs_csr(slot);
440 dbg("%s - slot %s HS_CSR (2) = %04x",
441 __func__, slot_name(slot), hs_csr);
443 if (update_latch_status(slot->hotplug_slot, 1))
444 warn("failure to update latch file");
446 if (update_adapter_status(slot->hotplug_slot, 1))
447 warn("failure to update adapter file");
449 cpci_led_off(slot);
451 /* GSM, debug */
452 hs_csr = cpci_get_hs_csr(slot);
453 dbg("%s - slot %s HS_CSR (3) = %04x",
454 __func__, slot_name(slot), hs_csr);
456 inserted++;
457 } else if (cpci_check_ext(slot)) {
458 /* Process extraction request */
459 dbg("%s - slot %s extracted",
460 __func__, slot_name(slot));
462 /* GSM, debug */
463 hs_csr = cpci_get_hs_csr(slot);
464 dbg("%s - slot %s HS_CSR = %04x",
465 __func__, slot_name(slot), hs_csr);
467 if (!slot->extracting) {
468 if (update_latch_status(slot->hotplug_slot, 0)) {
469 warn("failure to update latch file");
471 slot->extracting = 1;
472 atomic_inc(&extracting);
474 extracted++;
475 } else if (slot->extracting) {
476 hs_csr = cpci_get_hs_csr(slot);
477 if (hs_csr == 0xffff) {
479 * Hmmm, we're likely hosed at this point, should we
480 * bother trying to tell the driver or not?
482 err("card in slot %s was improperly removed",
483 slot_name(slot));
484 if (update_adapter_status(slot->hotplug_slot, 0))
485 warn("failure to update adapter file");
486 slot->extracting = 0;
487 atomic_dec(&extracting);
491 up_read(&list_rwsem);
492 dbg("inserted=%d, extracted=%d, extracting=%d",
493 inserted, extracted, atomic_read(&extracting));
494 if (inserted || extracted)
495 return extracted;
496 else if (!atomic_read(&extracting)) {
497 err("cannot find ENUM# source, shutting down");
498 return -1;
500 return 0;
503 /* This is the interrupt mode worker thread body */
504 static int
505 event_thread(void *data)
507 int rc;
509 dbg("%s - event thread started", __func__);
510 while (1) {
511 dbg("event thread sleeping");
512 set_current_state(TASK_INTERRUPTIBLE);
513 schedule();
514 if (kthread_should_stop())
515 break;
516 do {
517 rc = check_slots();
518 if (rc > 0) {
519 /* Give userspace a chance to handle extraction */
520 msleep(500);
521 } else if (rc < 0) {
522 dbg("%s - error checking slots", __func__);
523 thread_finished = 1;
524 goto out;
526 } while (atomic_read(&extracting) && !kthread_should_stop());
527 if (kthread_should_stop())
528 break;
530 /* Re-enable ENUM# interrupt */
531 dbg("%s - re-enabling irq", __func__);
532 controller->ops->enable_irq();
534 out:
535 return 0;
538 /* This is the polling mode worker thread body */
539 static int
540 poll_thread(void *data)
542 int rc;
544 while (1) {
545 if (kthread_should_stop() || signal_pending(current))
546 break;
547 if (controller->ops->query_enum()) {
548 do {
549 rc = check_slots();
550 if (rc > 0) {
551 /* Give userspace a chance to handle extraction */
552 msleep(500);
553 } else if (rc < 0) {
554 dbg("%s - error checking slots", __func__);
555 thread_finished = 1;
556 goto out;
558 } while (atomic_read(&extracting) && !kthread_should_stop());
560 msleep(100);
562 out:
563 return 0;
566 static int
567 cpci_start_thread(void)
569 if (controller->irq)
570 cpci_thread = kthread_run(event_thread, NULL, "cpci_hp_eventd");
571 else
572 cpci_thread = kthread_run(poll_thread, NULL, "cpci_hp_polld");
573 if (IS_ERR(cpci_thread)) {
574 err("Can't start up our thread");
575 return PTR_ERR(cpci_thread);
577 thread_finished = 0;
578 return 0;
581 static void
582 cpci_stop_thread(void)
584 kthread_stop(cpci_thread);
585 thread_finished = 1;
589 cpci_hp_register_controller(struct cpci_hp_controller *new_controller)
591 int status = 0;
593 if (controller)
594 return -1;
595 if (!(new_controller && new_controller->ops))
596 return -EINVAL;
597 if (new_controller->irq) {
598 if (!(new_controller->ops->enable_irq &&
599 new_controller->ops->disable_irq))
600 status = -EINVAL;
601 if (request_irq(new_controller->irq,
602 cpci_hp_intr,
603 new_controller->irq_flags,
604 MY_NAME,
605 new_controller->dev_id)) {
606 err("Can't get irq %d for the hotplug cPCI controller",
607 new_controller->irq);
608 status = -ENODEV;
610 dbg("%s - acquired controller irq %d",
611 __func__, new_controller->irq);
613 if (!status)
614 controller = new_controller;
615 return status;
618 static void
619 cleanup_slots(void)
621 struct slot *slot;
622 struct slot *tmp;
625 * Unregister all of our slots with the pci_hotplug subsystem,
626 * and free up all memory that we had allocated.
628 down_write(&list_rwsem);
629 if (!slots)
630 goto cleanup_null;
631 list_for_each_entry_safe(slot, tmp, &slot_list, slot_list) {
632 list_del(&slot->slot_list);
633 pci_hp_deregister(slot->hotplug_slot);
635 cleanup_null:
636 up_write(&list_rwsem);
637 return;
641 cpci_hp_unregister_controller(struct cpci_hp_controller *old_controller)
643 int status = 0;
645 if (controller) {
646 if (!thread_finished)
647 cpci_stop_thread();
648 if (controller->irq)
649 free_irq(controller->irq, controller->dev_id);
650 controller = NULL;
651 cleanup_slots();
652 } else
653 status = -ENODEV;
654 return status;
658 cpci_hp_start(void)
660 static int first = 1;
661 int status;
663 dbg("%s - enter", __func__);
664 if (!controller)
665 return -ENODEV;
667 down_read(&list_rwsem);
668 if (list_empty(&slot_list)) {
669 up_read(&list_rwsem);
670 return -ENODEV;
672 up_read(&list_rwsem);
674 status = init_slots(first);
675 if (first)
676 first = 0;
677 if (status)
678 return status;
680 status = cpci_start_thread();
681 if (status)
682 return status;
683 dbg("%s - thread started", __func__);
685 if (controller->irq) {
686 /* Start enum interrupt processing */
687 dbg("%s - enabling irq", __func__);
688 controller->ops->enable_irq();
690 dbg("%s - exit", __func__);
691 return 0;
695 cpci_hp_stop(void)
697 if (!controller)
698 return -ENODEV;
699 if (controller->irq) {
700 /* Stop enum interrupt processing */
701 dbg("%s - disabling irq", __func__);
702 controller->ops->disable_irq();
704 cpci_stop_thread();
705 return 0;
708 int __init
709 cpci_hotplug_init(int debug)
711 cpci_debug = debug;
712 return 0;
715 void __exit
716 cpci_hotplug_exit(void)
719 * Clean everything up.
721 cpci_hp_stop();
722 cpci_hp_unregister_controller(controller);
725 EXPORT_SYMBOL_GPL(cpci_hp_register_controller);
726 EXPORT_SYMBOL_GPL(cpci_hp_unregister_controller);
727 EXPORT_SYMBOL_GPL(cpci_hp_register_bus);
728 EXPORT_SYMBOL_GPL(cpci_hp_unregister_bus);
729 EXPORT_SYMBOL_GPL(cpci_hp_start);
730 EXPORT_SYMBOL_GPL(cpci_hp_stop);