1 // SPDX-License-Identifier: GPL-2.0+
3 * ACPI PCI HotPlug glue functions to ACPI CA subsystem
5 * Copyright (C) 2002,2003 Takayoshi Kochi (t-kochi@bq.jp.nec.com)
6 * Copyright (C) 2002 Hiroshi Aono (h-aono@ap.jp.nec.com)
7 * Copyright (C) 2002,2003 NEC Corporation
8 * Copyright (C) 2003-2005 Matthew Wilcox (matthew.wilcox@hp.com)
9 * Copyright (C) 2003-2005 Hewlett Packard
10 * Copyright (C) 2005 Rajesh Shah (rajesh.shah@intel.com)
11 * Copyright (C) 2005 Intel Corporation
13 * All rights reserved.
15 * Send feedback to <kristen.c.accardi@intel.com>
20 * Lifetime rules for pci_dev:
21 * - The one in acpiphp_bridge has its refcount elevated by pci_get_slot()
22 * when the bridge is scanned and it loses a refcount when the bridge
24 * - When a P2P bridge is present, we elevate the refcount on the subordinate
25 * bus. It loses the refcount when the the driver unloads.
28 #define pr_fmt(fmt) "acpiphp_glue: " fmt
30 #include <linux/module.h>
32 #include <linux/kernel.h>
33 #include <linux/pci.h>
34 #include <linux/pci_hotplug.h>
35 #include <linux/pci-acpi.h>
36 #include <linux/pm_runtime.h>
37 #include <linux/mutex.h>
38 #include <linux/slab.h>
39 #include <linux/acpi.h>
44 static LIST_HEAD(bridge_list);
45 static DEFINE_MUTEX(bridge_mutex);
47 static int acpiphp_hotplug_notify(struct acpi_device *adev, u32 type);
48 static void acpiphp_post_dock_fixup(struct acpi_device *adev);
49 static void acpiphp_sanitize_bus(struct pci_bus *bus);
50 static void hotplug_event(u32 type, struct acpiphp_context *context);
51 static void free_bridge(struct kref *kref);
54 * acpiphp_init_context - Create hotplug context and grab a reference to it.
55 * @adev: ACPI device object to create the context for.
57 * Call under acpi_hp_context_lock.
59 static struct acpiphp_context *acpiphp_init_context(struct acpi_device *adev)
61 struct acpiphp_context *context;
63 context = kzalloc(sizeof(*context), GFP_KERNEL);
67 context->refcount = 1;
68 context->hp.notify = acpiphp_hotplug_notify;
69 context->hp.fixup = acpiphp_post_dock_fixup;
70 acpi_set_hp_context(adev, &context->hp);
75 * acpiphp_get_context - Get hotplug context and grab a reference to it.
76 * @adev: ACPI device object to get the context for.
78 * Call under acpi_hp_context_lock.
80 static struct acpiphp_context *acpiphp_get_context(struct acpi_device *adev)
82 struct acpiphp_context *context;
87 context = to_acpiphp_context(adev->hp);
93 * acpiphp_put_context - Drop a reference to ACPI hotplug context.
94 * @context: ACPI hotplug context to drop a reference to.
96 * The context object is removed if there are no more references to it.
98 * Call under acpi_hp_context_lock.
100 static void acpiphp_put_context(struct acpiphp_context *context)
102 if (--context->refcount)
105 WARN_ON(context->bridge);
106 context->hp.self->hp = NULL;
110 static inline void get_bridge(struct acpiphp_bridge *bridge)
112 kref_get(&bridge->ref);
115 static inline void put_bridge(struct acpiphp_bridge *bridge)
117 kref_put(&bridge->ref, free_bridge);
120 static struct acpiphp_context *acpiphp_grab_context(struct acpi_device *adev)
122 struct acpiphp_context *context;
124 acpi_lock_hp_context();
126 context = acpiphp_get_context(adev);
130 if (context->func.parent->is_going_away) {
131 acpiphp_put_context(context);
136 get_bridge(context->func.parent);
137 acpiphp_put_context(context);
140 acpi_unlock_hp_context();
144 static void acpiphp_let_context_go(struct acpiphp_context *context)
146 put_bridge(context->func.parent);
149 static void free_bridge(struct kref *kref)
151 struct acpiphp_context *context;
152 struct acpiphp_bridge *bridge;
153 struct acpiphp_slot *slot, *next;
154 struct acpiphp_func *func, *tmp;
156 acpi_lock_hp_context();
158 bridge = container_of(kref, struct acpiphp_bridge, ref);
160 list_for_each_entry_safe(slot, next, &bridge->slots, node) {
161 list_for_each_entry_safe(func, tmp, &slot->funcs, sibling)
162 acpiphp_put_context(func_to_context(func));
167 context = bridge->context;
168 /* Root bridges will not have hotplug context. */
170 /* Release the reference taken by acpiphp_enumerate_slots(). */
171 put_bridge(context->func.parent);
172 context->bridge = NULL;
173 acpiphp_put_context(context);
176 put_device(&bridge->pci_bus->dev);
177 pci_dev_put(bridge->pci_dev);
180 acpi_unlock_hp_context();
184 * acpiphp_post_dock_fixup - Post-dock fixups for PCI devices.
185 * @adev: ACPI device object corresponding to a PCI device.
187 * TBD - figure out a way to only call fixups for systems that require them.
189 static void acpiphp_post_dock_fixup(struct acpi_device *adev)
191 struct acpiphp_context *context = acpiphp_grab_context(adev);
198 bus = context->func.slot->bus;
202 /* fixup bad _DCK function that rewrites
203 * secondary bridge on slot
205 pci_read_config_dword(bus->self, PCI_PRIMARY_BUS, &buses);
207 if (((buses >> 8) & 0xff) != bus->busn_res.start) {
208 buses = (buses & 0xff000000)
209 | ((unsigned int)(bus->primary) << 0)
210 | ((unsigned int)(bus->busn_res.start) << 8)
211 | ((unsigned int)(bus->busn_res.end) << 16);
212 pci_write_config_dword(bus->self, PCI_PRIMARY_BUS, buses);
216 acpiphp_let_context_go(context);
220 * acpiphp_add_context - Add ACPIPHP context to an ACPI device object.
221 * @handle: ACPI handle of the object to add a context to.
223 * @data: The object's parent ACPIPHP bridge.
226 static acpi_status acpiphp_add_context(acpi_handle handle, u32 lvl, void *data,
229 struct acpiphp_bridge *bridge = data;
230 struct acpiphp_context *context;
231 struct acpi_device *adev;
232 struct acpiphp_slot *slot;
233 struct acpiphp_func *newfunc;
234 acpi_status status = AE_OK;
235 unsigned long long adr;
236 int device, function;
237 struct pci_bus *pbus = bridge->pci_bus;
238 struct pci_dev *pdev = bridge->pci_dev;
241 status = acpi_evaluate_integer(handle, "_ADR", NULL, &adr);
242 if (ACPI_FAILURE(status)) {
243 if (status != AE_NOT_FOUND)
244 acpi_handle_warn(handle,
245 "can't evaluate _ADR (%#x)\n", status);
248 if (acpi_bus_get_device(handle, &adev))
251 device = (adr >> 16) & 0xffff;
252 function = adr & 0xffff;
254 acpi_lock_hp_context();
255 context = acpiphp_init_context(adev);
257 acpi_unlock_hp_context();
258 acpi_handle_err(handle, "No hotplug context\n");
261 newfunc = &context->func;
262 newfunc->function = function;
263 newfunc->parent = bridge;
264 acpi_unlock_hp_context();
267 * If this is a dock device, its _EJ0 should be executed by the dock
268 * notify handler after calling _DCK.
270 if (!is_dock_device(adev) && acpi_has_method(handle, "_EJ0"))
271 newfunc->flags = FUNC_HAS_EJ0;
273 if (acpi_has_method(handle, "_STA"))
274 newfunc->flags |= FUNC_HAS_STA;
276 /* search for objects that share the same slot */
277 list_for_each_entry(slot, &bridge->slots, node)
278 if (slot->device == device)
281 slot = kzalloc(sizeof(struct acpiphp_slot), GFP_KERNEL);
283 acpi_lock_hp_context();
284 acpiphp_put_context(context);
285 acpi_unlock_hp_context();
289 slot->bus = bridge->pci_bus;
290 slot->device = device;
291 INIT_LIST_HEAD(&slot->funcs);
293 list_add_tail(&slot->node, &bridge->slots);
296 * Expose slots to user space for functions that have _EJ0 or _RMV or
297 * are located in dock stations. Do not expose them for devices handled
298 * by the native PCIe hotplug (PCIeHP) or standard PCI hotplug
299 * (SHPCHP), because that code is supposed to expose slots to user
300 * space in those cases.
302 if ((acpi_pci_check_ejectable(pbus, handle) || is_dock_device(adev))
303 && !(pdev && hotplug_is_native(pdev))) {
304 unsigned long long sun;
308 status = acpi_evaluate_integer(handle, "_SUN", NULL, &sun);
309 if (ACPI_FAILURE(status))
310 sun = bridge->nr_slots;
312 pr_debug("found ACPI PCI Hotplug slot %llu at PCI %04x:%02x:%02x\n",
313 sun, pci_domain_nr(pbus), pbus->number, device);
315 retval = acpiphp_register_hotplug_slot(slot, sun);
319 if (retval == -EBUSY)
320 pr_warn("Slot %llu already registered by another hotplug driver\n", sun);
322 pr_warn("acpiphp_register_hotplug_slot failed (err code = 0x%x)\n", retval);
324 /* Even if the slot registration fails, we can still use it. */
328 newfunc->slot = slot;
329 list_add_tail(&newfunc->sibling, &slot->funcs);
331 if (pci_bus_read_dev_vendor_id(pbus, PCI_DEVFN(device, function),
333 slot->flags |= SLOT_ENABLED;
338 static void cleanup_bridge(struct acpiphp_bridge *bridge)
340 struct acpiphp_slot *slot;
341 struct acpiphp_func *func;
343 list_for_each_entry(slot, &bridge->slots, node) {
344 list_for_each_entry(func, &slot->funcs, sibling) {
345 struct acpi_device *adev = func_to_acpi_device(func);
347 acpi_lock_hp_context();
348 adev->hp->notify = NULL;
349 adev->hp->fixup = NULL;
350 acpi_unlock_hp_context();
352 slot->flags |= SLOT_IS_GOING_AWAY;
354 acpiphp_unregister_hotplug_slot(slot);
357 mutex_lock(&bridge_mutex);
358 list_del(&bridge->list);
359 mutex_unlock(&bridge_mutex);
361 acpi_lock_hp_context();
362 bridge->is_going_away = true;
363 acpi_unlock_hp_context();
367 * acpiphp_max_busnr - return the highest reserved bus number under the given bus.
368 * @bus: bus to start search with
370 static unsigned char acpiphp_max_busnr(struct pci_bus *bus)
373 unsigned char max, n;
376 * pci_bus_max_busnr will return the highest
377 * reserved busnr for all these children.
378 * that is equivalent to the bus->subordinate
379 * value. We don't want to use the parent's
380 * bus->subordinate value because it could have
383 max = bus->busn_res.start;
385 list_for_each_entry(tmp, &bus->children, node) {
386 n = pci_bus_max_busnr(tmp);
393 static void acpiphp_set_acpi_region(struct acpiphp_slot *slot)
395 struct acpiphp_func *func;
396 union acpi_object params[2];
397 struct acpi_object_list arg_list;
399 list_for_each_entry(func, &slot->funcs, sibling) {
401 arg_list.pointer = params;
402 params[0].type = ACPI_TYPE_INTEGER;
403 params[0].integer.value = ACPI_ADR_SPACE_PCI_CONFIG;
404 params[1].type = ACPI_TYPE_INTEGER;
405 params[1].integer.value = 1;
406 /* _REG is optional, we don't care about if there is failure */
407 acpi_evaluate_object(func_to_handle(func), "_REG", &arg_list,
412 static void check_hotplug_bridge(struct acpiphp_slot *slot, struct pci_dev *dev)
414 struct acpiphp_func *func;
416 /* quirk, or pcie could set it already */
417 if (dev->is_hotplug_bridge)
420 list_for_each_entry(func, &slot->funcs, sibling) {
421 if (PCI_FUNC(dev->devfn) == func->function) {
422 dev->is_hotplug_bridge = 1;
428 static int acpiphp_rescan_slot(struct acpiphp_slot *slot)
430 struct acpiphp_func *func;
432 list_for_each_entry(func, &slot->funcs, sibling) {
433 struct acpi_device *adev = func_to_acpi_device(func);
435 acpi_bus_scan(adev->handle);
436 if (acpi_device_enumerated(adev))
437 acpi_device_set_power(adev, ACPI_STATE_D0);
439 return pci_scan_slot(slot->bus, PCI_DEVFN(slot->device, 0));
442 static void acpiphp_native_scan_bridge(struct pci_dev *bridge)
444 struct pci_bus *bus = bridge->subordinate;
451 max = bus->busn_res.start;
452 /* Scan already configured non-hotplug bridges */
453 for_each_pci_bridge(dev, bus) {
454 if (!hotplug_is_native(dev))
455 max = pci_scan_bridge(bus, dev, max, 0);
458 /* Scan non-hotplug bridges that need to be reconfigured */
459 for_each_pci_bridge(dev, bus) {
460 if (hotplug_is_native(dev))
463 max = pci_scan_bridge(bus, dev, max, 1);
464 if (dev->subordinate) {
465 pcibios_resource_survey_bus(dev->subordinate);
466 pci_bus_size_bridges(dev->subordinate);
467 pci_bus_assign_resources(dev->subordinate);
473 * enable_slot - enable, configure a slot
474 * @slot: slot to be enabled
475 * @bridge: true if enable is for the whole bridge (not a single slot)
477 * This function should be called per *physical slot*,
478 * not per each slot object in ACPI namespace.
480 static void enable_slot(struct acpiphp_slot *slot, bool bridge)
483 struct pci_bus *bus = slot->bus;
484 struct acpiphp_func *func;
486 if (bridge && bus->self && hotplug_is_native(bus->self)) {
488 * If native hotplug is used, it will take care of hotplug
489 * slot management and resource allocation for hotplug
490 * bridges. However, ACPI hotplug may still be used for
491 * non-hotplug bridges to bring in additional devices such
492 * as a Thunderbolt host controller.
494 for_each_pci_bridge(dev, bus) {
495 if (PCI_SLOT(dev->devfn) == slot->device)
496 acpiphp_native_scan_bridge(dev);
502 acpiphp_rescan_slot(slot);
503 max = acpiphp_max_busnr(bus);
504 for (pass = 0; pass < 2; pass++) {
505 for_each_pci_bridge(dev, bus) {
506 if (PCI_SLOT(dev->devfn) != slot->device)
509 max = pci_scan_bridge(bus, dev, max, pass);
510 if (pass && dev->subordinate) {
511 check_hotplug_bridge(slot, dev);
512 pcibios_resource_survey_bus(dev->subordinate);
513 __pci_bus_size_bridges(dev->subordinate,
518 __pci_bus_assign_resources(bus, &add_list, NULL);
521 acpiphp_sanitize_bus(bus);
522 pcie_bus_configure_settings(bus);
523 acpiphp_set_acpi_region(slot);
525 list_for_each_entry(dev, &bus->devices, bus_list) {
526 /* Assume that newly added devices are powered on already. */
527 if (!pci_dev_is_added(dev))
528 dev->current_state = PCI_D0;
531 pci_bus_add_devices(bus);
533 slot->flags |= SLOT_ENABLED;
534 list_for_each_entry(func, &slot->funcs, sibling) {
535 dev = pci_get_slot(bus, PCI_DEVFN(slot->device,
538 /* Do not set SLOT_ENABLED flag if some funcs
540 slot->flags &= ~SLOT_ENABLED;
548 * disable_slot - disable a slot
549 * @slot: ACPI PHP slot
551 static void disable_slot(struct acpiphp_slot *slot)
553 struct pci_bus *bus = slot->bus;
554 struct pci_dev *dev, *prev;
555 struct acpiphp_func *func;
558 * enable_slot() enumerates all functions in this device via
559 * pci_scan_slot(), whether they have associated ACPI hotplug
560 * methods (_EJ0, etc.) or not. Therefore, we remove all functions
563 list_for_each_entry_safe_reverse(dev, prev, &bus->devices, bus_list)
564 if (PCI_SLOT(dev->devfn) == slot->device)
565 pci_stop_and_remove_bus_device(dev);
567 list_for_each_entry(func, &slot->funcs, sibling)
568 acpi_bus_trim(func_to_acpi_device(func));
570 slot->flags &= ~SLOT_ENABLED;
573 static bool slot_no_hotplug(struct acpiphp_slot *slot)
575 struct pci_bus *bus = slot->bus;
578 list_for_each_entry(dev, &bus->devices, bus_list) {
579 if (PCI_SLOT(dev->devfn) == slot->device && dev->ignore_hotplug)
586 * get_slot_status - get ACPI slot status
587 * @slot: ACPI PHP slot
589 * If a slot has _STA for each function and if any one of them
590 * returned non-zero status, return it.
592 * If a slot doesn't have _STA and if any one of its functions'
593 * configuration space is configured, return 0x0f as a _STA.
595 * Otherwise return 0.
597 static unsigned int get_slot_status(struct acpiphp_slot *slot)
599 unsigned long long sta = 0;
600 struct acpiphp_func *func;
603 list_for_each_entry(func, &slot->funcs, sibling) {
604 if (func->flags & FUNC_HAS_STA) {
607 status = acpi_evaluate_integer(func_to_handle(func),
609 if (ACPI_SUCCESS(status) && sta)
612 if (pci_bus_read_dev_vendor_id(slot->bus,
613 PCI_DEVFN(slot->device, func->function),
623 * Check for the slot itself since it may be that the
624 * ACPI slot is a device below PCIe upstream port so in
625 * that case it may not even be reachable yet.
627 if (pci_bus_read_dev_vendor_id(slot->bus,
628 PCI_DEVFN(slot->device, 0), &dvid, 0)) {
633 return (unsigned int)sta;
636 static inline bool device_status_valid(unsigned int sta)
639 * ACPI spec says that _STA may return bit 0 clear with bit 3 set
640 * if the device is valid but does not require a device driver to be
641 * loaded (Section 6.3.7 of ACPI 5.0A).
643 unsigned int mask = ACPI_STA_DEVICE_ENABLED | ACPI_STA_DEVICE_FUNCTIONING;
644 return (sta & mask) == mask;
648 * trim_stale_devices - remove PCI devices that are not responding.
649 * @dev: PCI device to start walking the hierarchy from.
651 static void trim_stale_devices(struct pci_dev *dev)
653 struct acpi_device *adev = ACPI_COMPANION(&dev->dev);
654 struct pci_bus *bus = dev->subordinate;
655 bool alive = dev->ignore_hotplug;
659 unsigned long long sta;
661 status = acpi_evaluate_integer(adev->handle, "_STA", NULL, &sta);
662 alive = alive || (ACPI_SUCCESS(status) && device_status_valid(sta));
665 alive = pci_device_is_present(dev);
668 pci_dev_set_disconnected(dev, NULL);
669 if (pci_has_subordinate(dev))
670 pci_walk_bus(dev->subordinate, pci_dev_set_disconnected,
673 pci_stop_and_remove_bus_device(dev);
677 struct pci_dev *child, *tmp;
679 /* The device is a bridge. so check the bus below it. */
680 pm_runtime_get_sync(&dev->dev);
681 list_for_each_entry_safe_reverse(child, tmp, &bus->devices, bus_list)
682 trim_stale_devices(child);
684 pm_runtime_put(&dev->dev);
689 * acpiphp_check_bridge - re-enumerate devices
690 * @bridge: where to begin re-enumeration
692 * Iterate over all slots under this bridge and make sure that if a
693 * card is present they are enabled, and if not they are disabled.
695 static void acpiphp_check_bridge(struct acpiphp_bridge *bridge)
697 struct acpiphp_slot *slot;
699 /* Bail out if the bridge is going away. */
700 if (bridge->is_going_away)
704 pm_runtime_get_sync(&bridge->pci_dev->dev);
706 list_for_each_entry(slot, &bridge->slots, node) {
707 struct pci_bus *bus = slot->bus;
708 struct pci_dev *dev, *tmp;
710 if (slot_no_hotplug(slot)) {
712 } else if (device_status_valid(get_slot_status(slot))) {
713 /* remove stale devices if any */
714 list_for_each_entry_safe_reverse(dev, tmp,
715 &bus->devices, bus_list)
716 if (PCI_SLOT(dev->devfn) == slot->device)
717 trim_stale_devices(dev);
719 /* configure all functions */
720 enable_slot(slot, true);
727 pm_runtime_put(&bridge->pci_dev->dev);
731 * Remove devices for which we could not assign resources, call
732 * arch specific code to fix-up the bus
734 static void acpiphp_sanitize_bus(struct pci_bus *bus)
736 struct pci_dev *dev, *tmp;
738 unsigned long type_mask = IORESOURCE_IO | IORESOURCE_MEM;
740 list_for_each_entry_safe_reverse(dev, tmp, &bus->devices, bus_list) {
741 for (i = 0; i < PCI_BRIDGE_RESOURCES; i++) {
742 struct resource *res = &dev->resource[i];
743 if ((res->flags & type_mask) && !res->start &&
745 /* Could not assign a required resources
746 * for this device, remove it */
747 pci_stop_and_remove_bus_device(dev);
755 * ACPI event handlers
758 void acpiphp_check_host_bridge(struct acpi_device *adev)
760 struct acpiphp_bridge *bridge = NULL;
762 acpi_lock_hp_context();
764 bridge = to_acpiphp_root_context(adev->hp)->root_bridge;
768 acpi_unlock_hp_context();
770 pci_lock_rescan_remove();
772 acpiphp_check_bridge(bridge);
774 pci_unlock_rescan_remove();
779 static int acpiphp_disable_and_eject_slot(struct acpiphp_slot *slot);
781 static void hotplug_event(u32 type, struct acpiphp_context *context)
783 acpi_handle handle = context->hp.self->handle;
784 struct acpiphp_func *func = &context->func;
785 struct acpiphp_slot *slot = func->slot;
786 struct acpiphp_bridge *bridge;
788 acpi_lock_hp_context();
789 bridge = context->bridge;
793 acpi_unlock_hp_context();
795 pci_lock_rescan_remove();
798 case ACPI_NOTIFY_BUS_CHECK:
799 /* bus re-enumerate */
800 acpi_handle_debug(handle, "Bus check in %s()\n", __func__);
802 acpiphp_check_bridge(bridge);
803 else if (!(slot->flags & SLOT_IS_GOING_AWAY))
804 enable_slot(slot, false);
808 case ACPI_NOTIFY_DEVICE_CHECK:
810 acpi_handle_debug(handle, "Device check in %s()\n", __func__);
812 acpiphp_check_bridge(bridge);
813 } else if (!(slot->flags & SLOT_IS_GOING_AWAY)) {
815 * Check if anything has changed in the slot and rescan
816 * from the parent if that's the case.
818 if (acpiphp_rescan_slot(slot))
819 acpiphp_check_bridge(func->parent);
823 case ACPI_NOTIFY_EJECT_REQUEST:
824 /* request device eject */
825 acpi_handle_debug(handle, "Eject request in %s()\n", __func__);
826 acpiphp_disable_and_eject_slot(slot);
830 pci_unlock_rescan_remove();
835 static int acpiphp_hotplug_notify(struct acpi_device *adev, u32 type)
837 struct acpiphp_context *context;
839 context = acpiphp_grab_context(adev);
843 hotplug_event(type, context);
844 acpiphp_let_context_go(context);
849 * acpiphp_enumerate_slots - Enumerate PCI slots for a given bus.
850 * @bus: PCI bus to enumerate the slots for.
852 * A "slot" is an object associated with a PCI device number. All functions
853 * (PCI devices) with the same bus and device number belong to the same slot.
855 void acpiphp_enumerate_slots(struct pci_bus *bus)
857 struct acpiphp_bridge *bridge;
858 struct acpi_device *adev;
862 if (acpiphp_disabled)
865 adev = ACPI_COMPANION(bus->bridge);
869 handle = adev->handle;
870 bridge = kzalloc(sizeof(struct acpiphp_bridge), GFP_KERNEL);
874 INIT_LIST_HEAD(&bridge->slots);
875 kref_init(&bridge->ref);
876 bridge->pci_dev = pci_dev_get(bus->self);
877 bridge->pci_bus = bus;
880 * Grab a ref to the subordinate PCI bus in case the bus is
881 * removed via PCI core logical hotplug. The ref pins the bus
882 * (which we access during module unload).
884 get_device(&bus->dev);
886 acpi_lock_hp_context();
887 if (pci_is_root_bus(bridge->pci_bus)) {
888 struct acpiphp_root_context *root_context;
890 root_context = kzalloc(sizeof(*root_context), GFP_KERNEL);
894 root_context->root_bridge = bridge;
895 acpi_set_hp_context(adev, &root_context->hp);
897 struct acpiphp_context *context;
900 * This bridge should have been registered as a hotplug function
901 * under its parent, so the context should be there, unless the
902 * parent is going to be handled by pciehp, in which case this
903 * bridge is not interesting to us either.
905 context = acpiphp_get_context(adev);
909 bridge->context = context;
910 context->bridge = bridge;
911 /* Get a reference to the parent bridge. */
912 get_bridge(context->func.parent);
914 acpi_unlock_hp_context();
916 /* Must be added to the list prior to calling acpiphp_add_context(). */
917 mutex_lock(&bridge_mutex);
918 list_add(&bridge->list, &bridge_list);
919 mutex_unlock(&bridge_mutex);
921 /* register all slot objects under this bridge */
922 status = acpi_walk_namespace(ACPI_TYPE_DEVICE, handle, 1,
923 acpiphp_add_context, NULL, bridge, NULL);
924 if (ACPI_FAILURE(status)) {
925 acpi_handle_err(handle, "failed to register slots\n");
926 cleanup_bridge(bridge);
932 acpi_unlock_hp_context();
933 put_device(&bus->dev);
934 pci_dev_put(bridge->pci_dev);
938 static void acpiphp_drop_bridge(struct acpiphp_bridge *bridge)
940 if (pci_is_root_bus(bridge->pci_bus)) {
941 struct acpiphp_root_context *root_context;
942 struct acpi_device *adev;
944 acpi_lock_hp_context();
945 adev = ACPI_COMPANION(bridge->pci_bus->bridge);
946 root_context = to_acpiphp_root_context(adev->hp);
948 acpi_unlock_hp_context();
951 cleanup_bridge(bridge);
956 * acpiphp_remove_slots - Remove slot objects associated with a given bus.
957 * @bus: PCI bus to remove the slot objects for.
959 void acpiphp_remove_slots(struct pci_bus *bus)
961 struct acpiphp_bridge *bridge;
963 if (acpiphp_disabled)
966 mutex_lock(&bridge_mutex);
967 list_for_each_entry(bridge, &bridge_list, list)
968 if (bridge->pci_bus == bus) {
969 mutex_unlock(&bridge_mutex);
970 acpiphp_drop_bridge(bridge);
974 mutex_unlock(&bridge_mutex);
978 * acpiphp_enable_slot - power on slot
979 * @slot: ACPI PHP slot
981 int acpiphp_enable_slot(struct acpiphp_slot *slot)
983 pci_lock_rescan_remove();
985 if (slot->flags & SLOT_IS_GOING_AWAY) {
986 pci_unlock_rescan_remove();
990 /* configure all functions */
991 if (!(slot->flags & SLOT_ENABLED))
992 enable_slot(slot, false);
994 pci_unlock_rescan_remove();
999 * acpiphp_disable_and_eject_slot - power off and eject slot
1000 * @slot: ACPI PHP slot
1002 static int acpiphp_disable_and_eject_slot(struct acpiphp_slot *slot)
1004 struct acpiphp_func *func;
1006 if (slot->flags & SLOT_IS_GOING_AWAY)
1009 /* unconfigure all functions */
1012 list_for_each_entry(func, &slot->funcs, sibling)
1013 if (func->flags & FUNC_HAS_EJ0) {
1014 acpi_handle handle = func_to_handle(func);
1016 if (ACPI_FAILURE(acpi_evaluate_ej0(handle)))
1017 acpi_handle_err(handle, "_EJ0 failed\n");
1025 int acpiphp_disable_slot(struct acpiphp_slot *slot)
1030 * Acquire acpi_scan_lock to ensure that the execution of _EJ0 in
1031 * acpiphp_disable_and_eject_slot() will be synchronized properly.
1033 acpi_scan_lock_acquire();
1034 pci_lock_rescan_remove();
1035 ret = acpiphp_disable_and_eject_slot(slot);
1036 pci_unlock_rescan_remove();
1037 acpi_scan_lock_release();
1045 u8 acpiphp_get_power_status(struct acpiphp_slot *slot)
1047 return (slot->flags & SLOT_ENABLED);
1054 u8 acpiphp_get_latch_status(struct acpiphp_slot *slot)
1056 return !(get_slot_status(slot) & ACPI_STA_DEVICE_UI);
1060 * adapter presence : 1
1063 u8 acpiphp_get_adapter_status(struct acpiphp_slot *slot)
1065 return !!get_slot_status(slot);