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[linux/fpc-iii.git] / drivers / pci / hotplug / sgi_hotplug.c
blob613043f7576f302c75bb5727d4dff910dd0aaaf2
1 /*
2 * This file is subject to the terms and conditions of the GNU General Public
3 * License. See the file "COPYING" in the main directory of this archive
4 * for more details.
6 * Copyright (C) 2005-2006 Silicon Graphics, Inc. All rights reserved.
8 * This work was based on the 2.4/2.6 kernel development by Dick Reigner.
9 * Work to add BIOS PROM support was completed by Mike Habeck.
12 #include <linux/acpi.h>
13 #include <linux/init.h>
14 #include <linux/kernel.h>
15 #include <linux/module.h>
16 #include <linux/pci.h>
17 #include <linux/pci_hotplug.h>
18 #include <linux/proc_fs.h>
19 #include <linux/slab.h>
20 #include <linux/types.h>
21 #include <linux/mutex.h>
23 #include <asm/sn/addrs.h>
24 #include <asm/sn/geo.h>
25 #include <asm/sn/l1.h>
26 #include <asm/sn/module.h>
27 #include <asm/sn/pcibr_provider.h>
28 #include <asm/sn/pcibus_provider_defs.h>
29 #include <asm/sn/pcidev.h>
30 #include <asm/sn/sn_feature_sets.h>
31 #include <asm/sn/sn_sal.h>
32 #include <asm/sn/types.h>
33 #include <asm/sn/acpi.h>
35 #include "../pci.h"
37 MODULE_LICENSE("GPL");
38 MODULE_AUTHOR("SGI (prarit@sgi.com, dickie@sgi.com, habeck@sgi.com)");
39 MODULE_DESCRIPTION("SGI Altix Hot Plug PCI Controller Driver");
42 /* SAL call error codes. Keep in sync with prom header io/include/pcibr.h */
43 #define PCI_SLOT_ALREADY_UP 2 /* slot already up */
44 #define PCI_SLOT_ALREADY_DOWN 3 /* slot already down */
45 #define PCI_L1_ERR 7 /* L1 console command error */
46 #define PCI_EMPTY_33MHZ 15 /* empty 33 MHz bus */
49 #define PCIIO_ASIC_TYPE_TIOCA 4
50 #define PCI_L1_QSIZE 128 /* our L1 message buffer size */
51 #define SN_MAX_HP_SLOTS 32 /* max hotplug slots */
52 #define SN_SLOT_NAME_SIZE 33 /* size of name string */
54 /* internal list head */
55 static struct list_head sn_hp_list;
57 /* hotplug_slot struct's private pointer */
58 struct slot {
59 int device_num;
60 struct pci_bus *pci_bus;
61 /* this struct for glue internal only */
62 struct hotplug_slot *hotplug_slot;
63 struct list_head hp_list;
64 char physical_path[SN_SLOT_NAME_SIZE];
67 struct pcibr_slot_enable_resp {
68 int resp_sub_errno;
69 char resp_l1_msg[PCI_L1_QSIZE + 1];
72 struct pcibr_slot_disable_resp {
73 int resp_sub_errno;
74 char resp_l1_msg[PCI_L1_QSIZE + 1];
77 enum sn_pci_req_e {
78 PCI_REQ_SLOT_ELIGIBLE,
79 PCI_REQ_SLOT_DISABLE
82 static int enable_slot(struct hotplug_slot *slot);
83 static int disable_slot(struct hotplug_slot *slot);
84 static inline int get_power_status(struct hotplug_slot *slot, u8 *value);
86 static struct hotplug_slot_ops sn_hotplug_slot_ops = {
87 .enable_slot = enable_slot,
88 .disable_slot = disable_slot,
89 .get_power_status = get_power_status,
92 static DEFINE_MUTEX(sn_hotplug_mutex);
94 static ssize_t path_show(struct pci_slot *pci_slot, char *buf)
96 int retval = -ENOENT;
97 struct slot *slot = pci_slot->hotplug->private;
99 if (!slot)
100 return retval;
102 retval = sprintf (buf, "%s\n", slot->physical_path);
103 return retval;
106 static struct pci_slot_attribute sn_slot_path_attr = __ATTR_RO(path);
108 static int sn_pci_slot_valid(struct pci_bus *pci_bus, int device)
110 struct pcibus_info *pcibus_info;
111 u16 busnum, segment, ioboard_type;
113 pcibus_info = SN_PCIBUS_BUSSOFT_INFO(pci_bus);
115 /* Check to see if this is a valid slot on 'pci_bus' */
116 if (!(pcibus_info->pbi_valid_devices & (1 << device)))
117 return -EPERM;
119 ioboard_type = sn_ioboard_to_pci_bus(pci_bus);
120 busnum = pcibus_info->pbi_buscommon.bs_persist_busnum;
121 segment = pci_domain_nr(pci_bus) & 0xf;
123 /* Do not allow hotplug operations on base I/O cards */
124 if ((ioboard_type == L1_BRICKTYPE_IX ||
125 ioboard_type == L1_BRICKTYPE_IA) &&
126 (segment == 1 && busnum == 0 && device != 1))
127 return -EPERM;
129 return 1;
132 static int sn_pci_bus_valid(struct pci_bus *pci_bus)
134 struct pcibus_info *pcibus_info;
135 u32 asic_type;
136 u16 ioboard_type;
138 /* Don't register slots hanging off the TIOCA bus */
139 pcibus_info = SN_PCIBUS_BUSSOFT_INFO(pci_bus);
140 asic_type = pcibus_info->pbi_buscommon.bs_asic_type;
141 if (asic_type == PCIIO_ASIC_TYPE_TIOCA)
142 return -EPERM;
144 /* Only register slots in I/O Bricks that support hotplug */
145 ioboard_type = sn_ioboard_to_pci_bus(pci_bus);
146 switch (ioboard_type) {
147 case L1_BRICKTYPE_IX:
148 case L1_BRICKTYPE_PX:
149 case L1_BRICKTYPE_IA:
150 case L1_BRICKTYPE_PA:
151 case L1_BOARDTYPE_PCIX3SLOT:
152 return 1;
153 break;
154 default:
155 return -EPERM;
156 break;
159 return -EIO;
162 static int sn_hp_slot_private_alloc(struct hotplug_slot *bss_hotplug_slot,
163 struct pci_bus *pci_bus, int device,
164 char *name)
166 struct pcibus_info *pcibus_info;
167 struct slot *slot;
169 pcibus_info = SN_PCIBUS_BUSSOFT_INFO(pci_bus);
171 slot = kzalloc(sizeof(*slot), GFP_KERNEL);
172 if (!slot)
173 return -ENOMEM;
174 bss_hotplug_slot->private = slot;
176 slot->device_num = device;
177 slot->pci_bus = pci_bus;
178 sprintf(name, "%04x:%02x:%02x",
179 pci_domain_nr(pci_bus),
180 ((u16)pcibus_info->pbi_buscommon.bs_persist_busnum),
181 device + 1);
183 sn_generate_path(pci_bus, slot->physical_path);
185 slot->hotplug_slot = bss_hotplug_slot;
186 list_add(&slot->hp_list, &sn_hp_list);
188 return 0;
191 static struct hotplug_slot * sn_hp_destroy(void)
193 struct slot *slot;
194 struct pci_slot *pci_slot;
195 struct hotplug_slot *bss_hotplug_slot = NULL;
197 list_for_each_entry(slot, &sn_hp_list, hp_list) {
198 bss_hotplug_slot = slot->hotplug_slot;
199 pci_slot = bss_hotplug_slot->pci_slot;
200 list_del(&((struct slot *)bss_hotplug_slot->private)->
201 hp_list);
202 sysfs_remove_file(&pci_slot->kobj,
203 &sn_slot_path_attr.attr);
204 break;
206 return bss_hotplug_slot;
209 static void sn_bus_free_data(struct pci_dev *dev)
211 struct pci_bus *subordinate_bus;
212 struct pci_dev *child;
214 /* Recursively clean up sn_irq_info structs */
215 if (dev->subordinate) {
216 subordinate_bus = dev->subordinate;
217 list_for_each_entry(child, &subordinate_bus->devices, bus_list)
218 sn_bus_free_data(child);
221 * Some drivers may use dma accesses during the
222 * driver remove function. We release the sysdata
223 * areas after the driver remove functions have
224 * been called.
226 sn_bus_store_sysdata(dev);
227 sn_pci_unfixup_slot(dev);
230 static int sn_slot_enable(struct hotplug_slot *bss_hotplug_slot,
231 int device_num, char **ssdt)
233 struct slot *slot = bss_hotplug_slot->private;
234 struct pcibus_info *pcibus_info;
235 struct pcibr_slot_enable_resp resp;
236 int rc;
238 pcibus_info = SN_PCIBUS_BUSSOFT_INFO(slot->pci_bus);
241 * Power-on and initialize the slot in the SN
242 * PCI infrastructure.
244 rc = sal_pcibr_slot_enable(pcibus_info, device_num, &resp, ssdt);
247 if (rc == PCI_SLOT_ALREADY_UP) {
248 dev_dbg(&slot->pci_bus->self->dev, "is already active\n");
249 return 1; /* return 1 to user */
252 if (rc == PCI_L1_ERR) {
253 dev_dbg(&slot->pci_bus->self->dev,
254 "L1 failure %d with message: %s",
255 resp.resp_sub_errno, resp.resp_l1_msg);
256 return -EPERM;
259 if (rc) {
260 dev_dbg(&slot->pci_bus->self->dev,
261 "insert failed with error %d sub-error %d\n",
262 rc, resp.resp_sub_errno);
263 return -EIO;
266 pcibus_info = SN_PCIBUS_BUSSOFT_INFO(slot->pci_bus);
267 pcibus_info->pbi_enabled_devices |= (1 << device_num);
269 return 0;
272 static int sn_slot_disable(struct hotplug_slot *bss_hotplug_slot,
273 int device_num, int action)
275 struct slot *slot = bss_hotplug_slot->private;
276 struct pcibus_info *pcibus_info;
277 struct pcibr_slot_disable_resp resp;
278 int rc;
280 pcibus_info = SN_PCIBUS_BUSSOFT_INFO(slot->pci_bus);
282 rc = sal_pcibr_slot_disable(pcibus_info, device_num, action, &resp);
284 if ((action == PCI_REQ_SLOT_ELIGIBLE) &&
285 (rc == PCI_SLOT_ALREADY_DOWN)) {
286 dev_dbg(&slot->pci_bus->self->dev, "Slot %s already inactive\n", slot->physical_path);
287 return 1; /* return 1 to user */
290 if ((action == PCI_REQ_SLOT_ELIGIBLE) && (rc == PCI_EMPTY_33MHZ)) {
291 dev_dbg(&slot->pci_bus->self->dev,
292 "Cannot remove last 33MHz card\n");
293 return -EPERM;
296 if ((action == PCI_REQ_SLOT_ELIGIBLE) && (rc == PCI_L1_ERR)) {
297 dev_dbg(&slot->pci_bus->self->dev,
298 "L1 failure %d with message \n%s\n",
299 resp.resp_sub_errno, resp.resp_l1_msg);
300 return -EPERM;
303 if ((action == PCI_REQ_SLOT_ELIGIBLE) && rc) {
304 dev_dbg(&slot->pci_bus->self->dev,
305 "remove failed with error %d sub-error %d\n",
306 rc, resp.resp_sub_errno);
307 return -EIO;
310 if ((action == PCI_REQ_SLOT_ELIGIBLE) && !rc)
311 return 0;
313 if ((action == PCI_REQ_SLOT_DISABLE) && !rc) {
314 pcibus_info = SN_PCIBUS_BUSSOFT_INFO(slot->pci_bus);
315 pcibus_info->pbi_enabled_devices &= ~(1 << device_num);
316 dev_dbg(&slot->pci_bus->self->dev, "remove successful\n");
317 return 0;
320 if ((action == PCI_REQ_SLOT_DISABLE) && rc) {
321 dev_dbg(&slot->pci_bus->self->dev,"remove failed rc = %d\n", rc);
324 return rc;
328 * Power up and configure the slot via a SAL call to PROM.
329 * Scan slot (and any children), do any platform specific fixup,
330 * and find device driver.
332 static int enable_slot(struct hotplug_slot *bss_hotplug_slot)
334 struct slot *slot = bss_hotplug_slot->private;
335 struct pci_bus *new_bus = NULL;
336 struct pci_dev *dev;
337 int num_funcs;
338 int new_ppb = 0;
339 int rc;
340 char *ssdt = NULL;
341 void pcibios_fixup_device_resources(struct pci_dev *);
343 /* Serialize the Linux PCI infrastructure */
344 mutex_lock(&sn_hotplug_mutex);
347 * Power-on and initialize the slot in the SN
348 * PCI infrastructure. Also, retrieve the ACPI SSDT
349 * table for the slot (if ACPI capable PROM).
351 rc = sn_slot_enable(bss_hotplug_slot, slot->device_num, &ssdt);
352 if (rc) {
353 mutex_unlock(&sn_hotplug_mutex);
354 return rc;
357 if (ssdt)
358 ssdt = __va(ssdt);
359 /* Add the new SSDT for the slot to the ACPI namespace */
360 if (SN_ACPI_BASE_SUPPORT() && ssdt) {
361 acpi_status ret;
363 ret = acpi_load_table((struct acpi_table_header *)ssdt);
364 if (ACPI_FAILURE(ret)) {
365 printk(KERN_ERR "%s: acpi_load_table failed (0x%x)\n",
366 __func__, ret);
367 /* try to continue on */
371 num_funcs = pci_scan_slot(slot->pci_bus,
372 PCI_DEVFN(slot->device_num + 1, 0));
373 if (!num_funcs) {
374 dev_dbg(&slot->pci_bus->self->dev, "no device in slot\n");
375 mutex_unlock(&sn_hotplug_mutex);
376 return -ENODEV;
380 * Map SN resources for all functions on the card
381 * to the Linux PCI interface and tell the drivers
382 * about them.
384 list_for_each_entry(dev, &slot->pci_bus->devices, bus_list) {
385 if (PCI_SLOT(dev->devfn) != slot->device_num + 1)
386 continue;
388 /* Need to do slot fixup on PPB before fixup of children
389 * (PPB's pcidev_info needs to be in pcidev_info list
390 * before child's SN_PCIDEV_INFO() call to setup
391 * pdi_host_pcidev_info).
393 pcibios_fixup_device_resources(dev);
394 if (SN_ACPI_BASE_SUPPORT())
395 sn_acpi_slot_fixup(dev);
396 else
397 sn_io_slot_fixup(dev);
398 if (dev->hdr_type == PCI_HEADER_TYPE_BRIDGE) {
399 pci_hp_add_bridge(dev);
400 if (dev->subordinate) {
401 new_bus = dev->subordinate;
402 new_ppb = 1;
408 * Add the slot's devices to the ACPI infrastructure */
409 if (SN_ACPI_BASE_SUPPORT() && ssdt) {
410 unsigned long long adr;
411 struct acpi_device *pdevice;
412 acpi_handle phandle;
413 acpi_handle chandle = NULL;
414 acpi_handle rethandle;
415 acpi_status ret;
417 phandle = acpi_device_handle(PCI_CONTROLLER(slot->pci_bus)->companion);
419 if (acpi_bus_get_device(phandle, &pdevice)) {
420 dev_dbg(&slot->pci_bus->self->dev,
421 "no parent device, assuming NULL\n");
422 pdevice = NULL;
425 acpi_scan_lock_acquire();
427 * Walk the rootbus node's immediate children looking for
428 * the slot's device node(s). There can be more than
429 * one for multifunction devices.
431 for (;;) {
432 rethandle = NULL;
433 ret = acpi_get_next_object(ACPI_TYPE_DEVICE,
434 phandle, chandle,
435 &rethandle);
437 if (ret == AE_NOT_FOUND || rethandle == NULL)
438 break;
440 chandle = rethandle;
442 ret = acpi_evaluate_integer(chandle, METHOD_NAME__ADR,
443 NULL, &adr);
445 if (ACPI_SUCCESS(ret) &&
446 (adr>>16) == (slot->device_num + 1)) {
448 ret = acpi_bus_scan(chandle);
449 if (ACPI_FAILURE(ret)) {
450 printk(KERN_ERR "%s: acpi_bus_scan "
451 "failed (0x%x) for slot %d "
452 "func %d\n", __func__,
453 ret, (int)(adr>>16),
454 (int)(adr&0xffff));
455 /* try to continue on */
459 acpi_scan_lock_release();
462 pci_lock_rescan_remove();
464 /* Call the driver for the new device */
465 pci_bus_add_devices(slot->pci_bus);
466 /* Call the drivers for the new devices subordinate to PPB */
467 if (new_ppb)
468 pci_bus_add_devices(new_bus);
470 pci_unlock_rescan_remove();
471 mutex_unlock(&sn_hotplug_mutex);
473 if (rc == 0)
474 dev_dbg(&slot->pci_bus->self->dev,
475 "insert operation successful\n");
476 else
477 dev_dbg(&slot->pci_bus->self->dev,
478 "insert operation failed rc = %d\n", rc);
480 return rc;
483 static int disable_slot(struct hotplug_slot *bss_hotplug_slot)
485 struct slot *slot = bss_hotplug_slot->private;
486 struct pci_dev *dev, *temp;
487 int rc;
488 acpi_owner_id ssdt_id = 0;
490 /* Acquire update access to the bus */
491 mutex_lock(&sn_hotplug_mutex);
493 /* is it okay to bring this slot down? */
494 rc = sn_slot_disable(bss_hotplug_slot, slot->device_num,
495 PCI_REQ_SLOT_ELIGIBLE);
496 if (rc)
497 goto leaving;
499 /* free the ACPI resources for the slot */
500 if (SN_ACPI_BASE_SUPPORT() &&
501 PCI_CONTROLLER(slot->pci_bus)->companion) {
502 unsigned long long adr;
503 struct acpi_device *device;
504 acpi_handle phandle;
505 acpi_handle chandle = NULL;
506 acpi_handle rethandle;
507 acpi_status ret;
509 /* Get the rootbus node pointer */
510 phandle = acpi_device_handle(PCI_CONTROLLER(slot->pci_bus)->companion);
512 acpi_scan_lock_acquire();
514 * Walk the rootbus node's immediate children looking for
515 * the slot's device node(s). There can be more than
516 * one for multifunction devices.
518 for (;;) {
519 rethandle = NULL;
520 ret = acpi_get_next_object(ACPI_TYPE_DEVICE,
521 phandle, chandle,
522 &rethandle);
524 if (ret == AE_NOT_FOUND || rethandle == NULL)
525 break;
527 chandle = rethandle;
529 ret = acpi_evaluate_integer(chandle,
530 METHOD_NAME__ADR,
531 NULL, &adr);
532 if (ACPI_SUCCESS(ret) &&
533 (adr>>16) == (slot->device_num + 1)) {
534 /* retain the owner id */
535 acpi_get_id(chandle, &ssdt_id);
537 ret = acpi_bus_get_device(chandle,
538 &device);
539 if (ACPI_SUCCESS(ret))
540 acpi_bus_trim(device);
543 acpi_scan_lock_release();
546 pci_lock_rescan_remove();
547 /* Free the SN resources assigned to the Linux device.*/
548 list_for_each_entry_safe(dev, temp, &slot->pci_bus->devices, bus_list) {
549 if (PCI_SLOT(dev->devfn) != slot->device_num + 1)
550 continue;
552 pci_dev_get(dev);
553 sn_bus_free_data(dev);
554 pci_stop_and_remove_bus_device(dev);
555 pci_dev_put(dev);
557 pci_unlock_rescan_remove();
559 /* Remove the SSDT for the slot from the ACPI namespace */
560 if (SN_ACPI_BASE_SUPPORT() && ssdt_id) {
561 acpi_status ret;
562 ret = acpi_unload_table_id(ssdt_id);
563 if (ACPI_FAILURE(ret)) {
564 printk(KERN_ERR "%s: acpi_unload_table_id "
565 "failed (0x%x) for id %d\n",
566 __func__, ret, ssdt_id);
567 /* try to continue on */
571 /* free the collected sysdata pointers */
572 sn_bus_free_sysdata();
574 /* Deactivate slot */
575 rc = sn_slot_disable(bss_hotplug_slot, slot->device_num,
576 PCI_REQ_SLOT_DISABLE);
577 leaving:
578 /* Release the bus lock */
579 mutex_unlock(&sn_hotplug_mutex);
581 return rc;
584 static inline int get_power_status(struct hotplug_slot *bss_hotplug_slot,
585 u8 *value)
587 struct slot *slot = bss_hotplug_slot->private;
588 struct pcibus_info *pcibus_info;
589 u32 power;
591 pcibus_info = SN_PCIBUS_BUSSOFT_INFO(slot->pci_bus);
592 mutex_lock(&sn_hotplug_mutex);
593 power = pcibus_info->pbi_enabled_devices & (1 << slot->device_num);
594 *value = power ? 1 : 0;
595 mutex_unlock(&sn_hotplug_mutex);
596 return 0;
599 static void sn_release_slot(struct hotplug_slot *bss_hotplug_slot)
601 kfree(bss_hotplug_slot->info);
602 kfree(bss_hotplug_slot->private);
603 kfree(bss_hotplug_slot);
606 static int sn_hotplug_slot_register(struct pci_bus *pci_bus)
608 int device;
609 struct pci_slot *pci_slot;
610 struct hotplug_slot *bss_hotplug_slot;
611 char name[SN_SLOT_NAME_SIZE];
612 int rc = 0;
615 * Currently only four devices are supported,
616 * in the future there maybe more -- up to 32.
619 for (device = 0; device < SN_MAX_HP_SLOTS ; device++) {
620 if (sn_pci_slot_valid(pci_bus, device) != 1)
621 continue;
623 bss_hotplug_slot = kzalloc(sizeof(*bss_hotplug_slot),
624 GFP_KERNEL);
625 if (!bss_hotplug_slot) {
626 rc = -ENOMEM;
627 goto alloc_err;
630 bss_hotplug_slot->info =
631 kzalloc(sizeof(struct hotplug_slot_info),
632 GFP_KERNEL);
633 if (!bss_hotplug_slot->info) {
634 rc = -ENOMEM;
635 goto alloc_err;
638 if (sn_hp_slot_private_alloc(bss_hotplug_slot,
639 pci_bus, device, name)) {
640 rc = -ENOMEM;
641 goto alloc_err;
643 bss_hotplug_slot->ops = &sn_hotplug_slot_ops;
644 bss_hotplug_slot->release = &sn_release_slot;
646 rc = pci_hp_register(bss_hotplug_slot, pci_bus, device, name);
647 if (rc)
648 goto register_err;
650 pci_slot = bss_hotplug_slot->pci_slot;
651 rc = sysfs_create_file(&pci_slot->kobj,
652 &sn_slot_path_attr.attr);
653 if (rc)
654 goto register_err;
656 dev_dbg(&pci_bus->self->dev, "Registered bus with hotplug\n");
657 return rc;
659 register_err:
660 dev_dbg(&pci_bus->self->dev, "bus failed to register with err = %d\n",
661 rc);
663 alloc_err:
664 if (rc == -ENOMEM)
665 dev_dbg(&pci_bus->self->dev, "Memory allocation error\n");
667 /* destroy THIS element */
668 if (bss_hotplug_slot)
669 sn_release_slot(bss_hotplug_slot);
671 /* destroy anything else on the list */
672 while ((bss_hotplug_slot = sn_hp_destroy()))
673 pci_hp_deregister(bss_hotplug_slot);
675 return rc;
678 static int __init sn_pci_hotplug_init(void)
680 struct pci_bus *pci_bus = NULL;
681 int rc;
682 int registered = 0;
684 if (!sn_prom_feature_available(PRF_HOTPLUG_SUPPORT)) {
685 printk(KERN_ERR "%s: PROM version does not support hotplug.\n",
686 __func__);
687 return -EPERM;
690 INIT_LIST_HEAD(&sn_hp_list);
692 while ((pci_bus = pci_find_next_bus(pci_bus))) {
693 if (!pci_bus->sysdata)
694 continue;
696 rc = sn_pci_bus_valid(pci_bus);
697 if (rc != 1) {
698 dev_dbg(&pci_bus->self->dev, "not a valid hotplug bus\n");
699 continue;
701 dev_dbg(&pci_bus->self->dev, "valid hotplug bus\n");
703 rc = sn_hotplug_slot_register(pci_bus);
704 if (!rc) {
705 registered = 1;
706 } else {
707 registered = 0;
708 break;
712 return registered == 1 ? 0 : -ENODEV;
715 static void __exit sn_pci_hotplug_exit(void)
717 struct hotplug_slot *bss_hotplug_slot;
719 while ((bss_hotplug_slot = sn_hp_destroy()))
720 pci_hp_deregister(bss_hotplug_slot);
722 if (!list_empty(&sn_hp_list))
723 printk(KERN_ERR "%s: internal list is not empty\n", __FILE__);
726 module_init(sn_pci_hotplug_init);
727 module_exit(sn_pci_hotplug_exit);