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path: root/drivers/pci/hotplug/acpiphp_glue.c
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Diffstat (limited to 'drivers/pci/hotplug/acpiphp_glue.c')
-rw-r--r--drivers/pci/hotplug/acpiphp_glue.c1068
1 files changed, 1068 insertions, 0 deletions
diff --git a/drivers/pci/hotplug/acpiphp_glue.c b/drivers/pci/hotplug/acpiphp_glue.c
new file mode 100644
index 0000000000..5b1f271c60
--- /dev/null
+++ b/drivers/pci/hotplug/acpiphp_glue.c
@@ -0,0 +1,1068 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * ACPI PCI HotPlug glue functions to ACPI CA subsystem
+ *
+ * Copyright (C) 2002,2003 Takayoshi Kochi (t-kochi@bq.jp.nec.com)
+ * Copyright (C) 2002 Hiroshi Aono (h-aono@ap.jp.nec.com)
+ * Copyright (C) 2002,2003 NEC Corporation
+ * Copyright (C) 2003-2005 Matthew Wilcox (willy@infradead.org)
+ * Copyright (C) 2003-2005 Hewlett Packard
+ * Copyright (C) 2005 Rajesh Shah (rajesh.shah@intel.com)
+ * Copyright (C) 2005 Intel Corporation
+ *
+ * All rights reserved.
+ *
+ * Send feedback to <kristen.c.accardi@intel.com>
+ *
+ */
+
+/*
+ * Lifetime rules for pci_dev:
+ * - The one in acpiphp_bridge has its refcount elevated by pci_get_slot()
+ * when the bridge is scanned and it loses a refcount when the bridge
+ * is removed.
+ * - When a P2P bridge is present, we elevate the refcount on the subordinate
+ * bus. It loses the refcount when the driver unloads.
+ */
+
+#define pr_fmt(fmt) "acpiphp_glue: " fmt
+
+#include <linux/module.h>
+
+#include <linux/kernel.h>
+#include <linux/pci.h>
+#include <linux/pci_hotplug.h>
+#include <linux/pci-acpi.h>
+#include <linux/pm_runtime.h>
+#include <linux/mutex.h>
+#include <linux/slab.h>
+#include <linux/acpi.h>
+
+#include "../pci.h"
+#include "acpiphp.h"
+
+static LIST_HEAD(bridge_list);
+static DEFINE_MUTEX(bridge_mutex);
+
+static int acpiphp_hotplug_notify(struct acpi_device *adev, u32 type);
+static void acpiphp_post_dock_fixup(struct acpi_device *adev);
+static void acpiphp_sanitize_bus(struct pci_bus *bus);
+static void hotplug_event(u32 type, struct acpiphp_context *context);
+static void free_bridge(struct kref *kref);
+
+/**
+ * acpiphp_init_context - Create hotplug context and grab a reference to it.
+ * @adev: ACPI device object to create the context for.
+ *
+ * Call under acpi_hp_context_lock.
+ */
+static struct acpiphp_context *acpiphp_init_context(struct acpi_device *adev)
+{
+ struct acpiphp_context *context;
+
+ context = kzalloc(sizeof(*context), GFP_KERNEL);
+ if (!context)
+ return NULL;
+
+ context->refcount = 1;
+ context->hp.notify = acpiphp_hotplug_notify;
+ context->hp.fixup = acpiphp_post_dock_fixup;
+ acpi_set_hp_context(adev, &context->hp);
+ return context;
+}
+
+/**
+ * acpiphp_get_context - Get hotplug context and grab a reference to it.
+ * @adev: ACPI device object to get the context for.
+ *
+ * Call under acpi_hp_context_lock.
+ */
+static struct acpiphp_context *acpiphp_get_context(struct acpi_device *adev)
+{
+ struct acpiphp_context *context;
+
+ if (!adev->hp)
+ return NULL;
+
+ context = to_acpiphp_context(adev->hp);
+ context->refcount++;
+ return context;
+}
+
+/**
+ * acpiphp_put_context - Drop a reference to ACPI hotplug context.
+ * @context: ACPI hotplug context to drop a reference to.
+ *
+ * The context object is removed if there are no more references to it.
+ *
+ * Call under acpi_hp_context_lock.
+ */
+static void acpiphp_put_context(struct acpiphp_context *context)
+{
+ if (--context->refcount)
+ return;
+
+ WARN_ON(context->bridge);
+ context->hp.self->hp = NULL;
+ kfree(context);
+}
+
+static inline void get_bridge(struct acpiphp_bridge *bridge)
+{
+ kref_get(&bridge->ref);
+}
+
+static inline void put_bridge(struct acpiphp_bridge *bridge)
+{
+ kref_put(&bridge->ref, free_bridge);
+}
+
+static struct acpiphp_context *acpiphp_grab_context(struct acpi_device *adev)
+{
+ struct acpiphp_context *context;
+
+ acpi_lock_hp_context();
+
+ context = acpiphp_get_context(adev);
+ if (!context)
+ goto unlock;
+
+ if (context->func.parent->is_going_away) {
+ acpiphp_put_context(context);
+ context = NULL;
+ goto unlock;
+ }
+
+ get_bridge(context->func.parent);
+ acpiphp_put_context(context);
+
+unlock:
+ acpi_unlock_hp_context();
+ return context;
+}
+
+static void acpiphp_let_context_go(struct acpiphp_context *context)
+{
+ put_bridge(context->func.parent);
+}
+
+static void free_bridge(struct kref *kref)
+{
+ struct acpiphp_context *context;
+ struct acpiphp_bridge *bridge;
+ struct acpiphp_slot *slot, *next;
+ struct acpiphp_func *func, *tmp;
+
+ acpi_lock_hp_context();
+
+ bridge = container_of(kref, struct acpiphp_bridge, ref);
+
+ list_for_each_entry_safe(slot, next, &bridge->slots, node) {
+ list_for_each_entry_safe(func, tmp, &slot->funcs, sibling)
+ acpiphp_put_context(func_to_context(func));
+
+ kfree(slot);
+ }
+
+ context = bridge->context;
+ /* Root bridges will not have hotplug context. */
+ if (context) {
+ /* Release the reference taken by acpiphp_enumerate_slots(). */
+ put_bridge(context->func.parent);
+ context->bridge = NULL;
+ acpiphp_put_context(context);
+ }
+
+ put_device(&bridge->pci_bus->dev);
+ pci_dev_put(bridge->pci_dev);
+ kfree(bridge);
+
+ acpi_unlock_hp_context();
+}
+
+/**
+ * acpiphp_post_dock_fixup - Post-dock fixups for PCI devices.
+ * @adev: ACPI device object corresponding to a PCI device.
+ *
+ * TBD - figure out a way to only call fixups for systems that require them.
+ */
+static void acpiphp_post_dock_fixup(struct acpi_device *adev)
+{
+ struct acpiphp_context *context = acpiphp_grab_context(adev);
+ struct pci_bus *bus;
+ u32 buses;
+
+ if (!context)
+ return;
+
+ bus = context->func.slot->bus;
+ if (!bus->self)
+ goto out;
+
+ /* fixup bad _DCK function that rewrites
+ * secondary bridge on slot
+ */
+ pci_read_config_dword(bus->self, PCI_PRIMARY_BUS, &buses);
+
+ if (((buses >> 8) & 0xff) != bus->busn_res.start) {
+ buses = (buses & 0xff000000)
+ | ((unsigned int)(bus->primary) << 0)
+ | ((unsigned int)(bus->busn_res.start) << 8)
+ | ((unsigned int)(bus->busn_res.end) << 16);
+ pci_write_config_dword(bus->self, PCI_PRIMARY_BUS, buses);
+ }
+
+ out:
+ acpiphp_let_context_go(context);
+}
+
+/**
+ * acpiphp_add_context - Add ACPIPHP context to an ACPI device object.
+ * @handle: ACPI handle of the object to add a context to.
+ * @lvl: Not used.
+ * @data: The object's parent ACPIPHP bridge.
+ * @rv: Not used.
+ */
+static acpi_status acpiphp_add_context(acpi_handle handle, u32 lvl, void *data,
+ void **rv)
+{
+ struct acpi_device *adev = acpi_fetch_acpi_dev(handle);
+ struct acpiphp_bridge *bridge = data;
+ struct acpiphp_context *context;
+ struct acpiphp_slot *slot;
+ struct acpiphp_func *newfunc;
+ acpi_status status = AE_OK;
+ unsigned long long adr;
+ int device, function;
+ struct pci_bus *pbus = bridge->pci_bus;
+ struct pci_dev *pdev = bridge->pci_dev;
+ u32 val;
+
+ if (!adev)
+ return AE_OK;
+
+ status = acpi_evaluate_integer(handle, "_ADR", NULL, &adr);
+ if (ACPI_FAILURE(status)) {
+ if (status != AE_NOT_FOUND)
+ acpi_handle_warn(handle,
+ "can't evaluate _ADR (%#x)\n", status);
+ return AE_OK;
+ }
+
+ device = (adr >> 16) & 0xffff;
+ function = adr & 0xffff;
+
+ acpi_lock_hp_context();
+ context = acpiphp_init_context(adev);
+ if (!context) {
+ acpi_unlock_hp_context();
+ acpi_handle_err(handle, "No hotplug context\n");
+ return AE_NOT_EXIST;
+ }
+ newfunc = &context->func;
+ newfunc->function = function;
+ newfunc->parent = bridge;
+ acpi_unlock_hp_context();
+
+ /*
+ * If this is a dock device, its _EJ0 should be executed by the dock
+ * notify handler after calling _DCK.
+ */
+ if (!is_dock_device(adev) && acpi_has_method(handle, "_EJ0"))
+ newfunc->flags = FUNC_HAS_EJ0;
+
+ if (acpi_has_method(handle, "_STA"))
+ newfunc->flags |= FUNC_HAS_STA;
+
+ /* search for objects that share the same slot */
+ list_for_each_entry(slot, &bridge->slots, node)
+ if (slot->device == device)
+ goto slot_found;
+
+ slot = kzalloc(sizeof(struct acpiphp_slot), GFP_KERNEL);
+ if (!slot) {
+ acpi_lock_hp_context();
+ acpiphp_put_context(context);
+ acpi_unlock_hp_context();
+ return AE_NO_MEMORY;
+ }
+
+ slot->bus = bridge->pci_bus;
+ slot->device = device;
+ INIT_LIST_HEAD(&slot->funcs);
+
+ list_add_tail(&slot->node, &bridge->slots);
+
+ /*
+ * Expose slots to user space for functions that have _EJ0 or _RMV or
+ * are located in dock stations. Do not expose them for devices handled
+ * by the native PCIe hotplug (PCIeHP) or standard PCI hotplug
+ * (SHPCHP), because that code is supposed to expose slots to user
+ * space in those cases.
+ */
+ if ((acpi_pci_check_ejectable(pbus, handle) || is_dock_device(adev))
+ && !(pdev && hotplug_is_native(pdev))) {
+ unsigned long long sun;
+ int retval;
+
+ bridge->nr_slots++;
+ status = acpi_evaluate_integer(handle, "_SUN", NULL, &sun);
+ if (ACPI_FAILURE(status))
+ sun = bridge->nr_slots;
+
+ pr_debug("found ACPI PCI Hotplug slot %llu at PCI %04x:%02x:%02x\n",
+ sun, pci_domain_nr(pbus), pbus->number, device);
+
+ retval = acpiphp_register_hotplug_slot(slot, sun);
+ if (retval) {
+ slot->slot = NULL;
+ bridge->nr_slots--;
+ if (retval == -EBUSY)
+ pr_warn("Slot %llu already registered by another hotplug driver\n", sun);
+ else
+ pr_warn("acpiphp_register_hotplug_slot failed (err code = 0x%x)\n", retval);
+ }
+ /* Even if the slot registration fails, we can still use it. */
+ }
+
+ slot_found:
+ newfunc->slot = slot;
+ list_add_tail(&newfunc->sibling, &slot->funcs);
+
+ if (pci_bus_read_dev_vendor_id(pbus, PCI_DEVFN(device, function),
+ &val, 60*1000))
+ slot->flags |= SLOT_ENABLED;
+
+ return AE_OK;
+}
+
+static void cleanup_bridge(struct acpiphp_bridge *bridge)
+{
+ struct acpiphp_slot *slot;
+ struct acpiphp_func *func;
+
+ list_for_each_entry(slot, &bridge->slots, node) {
+ list_for_each_entry(func, &slot->funcs, sibling) {
+ struct acpi_device *adev = func_to_acpi_device(func);
+
+ acpi_lock_hp_context();
+ adev->hp->notify = NULL;
+ adev->hp->fixup = NULL;
+ acpi_unlock_hp_context();
+ }
+ slot->flags |= SLOT_IS_GOING_AWAY;
+ if (slot->slot)
+ acpiphp_unregister_hotplug_slot(slot);
+ }
+
+ mutex_lock(&bridge_mutex);
+ list_del(&bridge->list);
+ mutex_unlock(&bridge_mutex);
+
+ acpi_lock_hp_context();
+ bridge->is_going_away = true;
+ acpi_unlock_hp_context();
+}
+
+/**
+ * acpiphp_max_busnr - return the highest reserved bus number under the given bus.
+ * @bus: bus to start search with
+ */
+static unsigned char acpiphp_max_busnr(struct pci_bus *bus)
+{
+ struct pci_bus *tmp;
+ unsigned char max, n;
+
+ /*
+ * pci_bus_max_busnr will return the highest
+ * reserved busnr for all these children.
+ * that is equivalent to the bus->subordinate
+ * value. We don't want to use the parent's
+ * bus->subordinate value because it could have
+ * padding in it.
+ */
+ max = bus->busn_res.start;
+
+ list_for_each_entry(tmp, &bus->children, node) {
+ n = pci_bus_max_busnr(tmp);
+ if (n > max)
+ max = n;
+ }
+ return max;
+}
+
+static void acpiphp_set_acpi_region(struct acpiphp_slot *slot)
+{
+ struct acpiphp_func *func;
+
+ list_for_each_entry(func, &slot->funcs, sibling) {
+ /* _REG is optional, we don't care about if there is failure */
+ acpi_evaluate_reg(func_to_handle(func),
+ ACPI_ADR_SPACE_PCI_CONFIG,
+ ACPI_REG_CONNECT);
+ }
+}
+
+static void check_hotplug_bridge(struct acpiphp_slot *slot, struct pci_dev *dev)
+{
+ struct acpiphp_func *func;
+
+ /* quirk, or pcie could set it already */
+ if (dev->is_hotplug_bridge)
+ return;
+
+ /*
+ * In the PCIe case, only Root Ports and Downstream Ports are capable of
+ * accommodating hotplug devices, so avoid marking Upstream Ports as
+ * "hotplug bridges".
+ */
+ if (pci_is_pcie(dev) && pci_pcie_type(dev) == PCI_EXP_TYPE_UPSTREAM)
+ return;
+
+ list_for_each_entry(func, &slot->funcs, sibling) {
+ if (PCI_FUNC(dev->devfn) == func->function) {
+ dev->is_hotplug_bridge = 1;
+ break;
+ }
+ }
+}
+
+static int acpiphp_rescan_slot(struct acpiphp_slot *slot)
+{
+ struct acpiphp_func *func;
+
+ list_for_each_entry(func, &slot->funcs, sibling) {
+ struct acpi_device *adev = func_to_acpi_device(func);
+
+ acpi_bus_scan(adev->handle);
+ if (acpi_device_enumerated(adev))
+ acpi_device_set_power(adev, ACPI_STATE_D0);
+ }
+ return pci_scan_slot(slot->bus, PCI_DEVFN(slot->device, 0));
+}
+
+static void acpiphp_native_scan_bridge(struct pci_dev *bridge)
+{
+ struct pci_bus *bus = bridge->subordinate;
+ struct pci_dev *dev;
+ int max;
+
+ if (!bus)
+ return;
+
+ max = bus->busn_res.start;
+ /* Scan already configured non-hotplug bridges */
+ for_each_pci_bridge(dev, bus) {
+ if (!hotplug_is_native(dev))
+ max = pci_scan_bridge(bus, dev, max, 0);
+ }
+
+ /* Scan non-hotplug bridges that need to be reconfigured */
+ for_each_pci_bridge(dev, bus) {
+ if (hotplug_is_native(dev))
+ continue;
+
+ max = pci_scan_bridge(bus, dev, max, 1);
+ if (dev->subordinate) {
+ pcibios_resource_survey_bus(dev->subordinate);
+ pci_bus_size_bridges(dev->subordinate);
+ pci_bus_assign_resources(dev->subordinate);
+ }
+ }
+}
+
+/**
+ * enable_slot - enable, configure a slot
+ * @slot: slot to be enabled
+ * @bridge: true if enable is for the whole bridge (not a single slot)
+ *
+ * This function should be called per *physical slot*,
+ * not per each slot object in ACPI namespace.
+ */
+static void enable_slot(struct acpiphp_slot *slot, bool bridge)
+{
+ struct pci_dev *dev;
+ struct pci_bus *bus = slot->bus;
+ struct acpiphp_func *func;
+
+ if (bridge && bus->self && hotplug_is_native(bus->self)) {
+ /*
+ * If native hotplug is used, it will take care of hotplug
+ * slot management and resource allocation for hotplug
+ * bridges. However, ACPI hotplug may still be used for
+ * non-hotplug bridges to bring in additional devices such
+ * as a Thunderbolt host controller.
+ */
+ for_each_pci_bridge(dev, bus) {
+ if (PCI_SLOT(dev->devfn) == slot->device)
+ acpiphp_native_scan_bridge(dev);
+ }
+ } else {
+ LIST_HEAD(add_list);
+ int max, pass;
+
+ acpiphp_rescan_slot(slot);
+ max = acpiphp_max_busnr(bus);
+ for (pass = 0; pass < 2; pass++) {
+ for_each_pci_bridge(dev, bus) {
+ if (PCI_SLOT(dev->devfn) != slot->device)
+ continue;
+
+ max = pci_scan_bridge(bus, dev, max, pass);
+ if (pass && dev->subordinate) {
+ check_hotplug_bridge(slot, dev);
+ pcibios_resource_survey_bus(dev->subordinate);
+ __pci_bus_size_bridges(dev->subordinate,
+ &add_list);
+ }
+ }
+ }
+ __pci_bus_assign_resources(bus, &add_list, NULL);
+ }
+
+ acpiphp_sanitize_bus(bus);
+ pcie_bus_configure_settings(bus);
+ acpiphp_set_acpi_region(slot);
+
+ list_for_each_entry(dev, &bus->devices, bus_list) {
+ /* Assume that newly added devices are powered on already. */
+ if (!pci_dev_is_added(dev))
+ dev->current_state = PCI_D0;
+ }
+
+ pci_bus_add_devices(bus);
+
+ slot->flags |= SLOT_ENABLED;
+ list_for_each_entry(func, &slot->funcs, sibling) {
+ dev = pci_get_slot(bus, PCI_DEVFN(slot->device,
+ func->function));
+ if (!dev) {
+ /* Do not set SLOT_ENABLED flag if some funcs
+ are not added. */
+ slot->flags &= ~SLOT_ENABLED;
+ continue;
+ }
+ pci_dev_put(dev);
+ }
+}
+
+/**
+ * disable_slot - disable a slot
+ * @slot: ACPI PHP slot
+ */
+static void disable_slot(struct acpiphp_slot *slot)
+{
+ struct pci_bus *bus = slot->bus;
+ struct pci_dev *dev, *prev;
+ struct acpiphp_func *func;
+
+ /*
+ * enable_slot() enumerates all functions in this device via
+ * pci_scan_slot(), whether they have associated ACPI hotplug
+ * methods (_EJ0, etc.) or not. Therefore, we remove all functions
+ * here.
+ */
+ list_for_each_entry_safe_reverse(dev, prev, &bus->devices, bus_list)
+ if (PCI_SLOT(dev->devfn) == slot->device)
+ pci_stop_and_remove_bus_device(dev);
+
+ list_for_each_entry(func, &slot->funcs, sibling)
+ acpi_bus_trim(func_to_acpi_device(func));
+
+ slot->flags &= ~SLOT_ENABLED;
+}
+
+static bool slot_no_hotplug(struct acpiphp_slot *slot)
+{
+ struct pci_bus *bus = slot->bus;
+ struct pci_dev *dev;
+
+ list_for_each_entry(dev, &bus->devices, bus_list) {
+ if (PCI_SLOT(dev->devfn) == slot->device && dev->ignore_hotplug)
+ return true;
+ }
+ return false;
+}
+
+/**
+ * get_slot_status - get ACPI slot status
+ * @slot: ACPI PHP slot
+ *
+ * If a slot has _STA for each function and if any one of them
+ * returned non-zero status, return it.
+ *
+ * If a slot doesn't have _STA and if any one of its functions'
+ * configuration space is configured, return 0x0f as a _STA.
+ *
+ * Otherwise return 0.
+ */
+static unsigned int get_slot_status(struct acpiphp_slot *slot)
+{
+ unsigned long long sta = 0;
+ struct acpiphp_func *func;
+ u32 dvid;
+
+ list_for_each_entry(func, &slot->funcs, sibling) {
+ if (func->flags & FUNC_HAS_STA) {
+ acpi_status status;
+
+ status = acpi_evaluate_integer(func_to_handle(func),
+ "_STA", NULL, &sta);
+ if (ACPI_SUCCESS(status) && sta)
+ break;
+ } else {
+ if (pci_bus_read_dev_vendor_id(slot->bus,
+ PCI_DEVFN(slot->device, func->function),
+ &dvid, 0)) {
+ sta = ACPI_STA_ALL;
+ break;
+ }
+ }
+ }
+
+ if (!sta) {
+ /*
+ * Check for the slot itself since it may be that the
+ * ACPI slot is a device below PCIe upstream port so in
+ * that case it may not even be reachable yet.
+ */
+ if (pci_bus_read_dev_vendor_id(slot->bus,
+ PCI_DEVFN(slot->device, 0), &dvid, 0)) {
+ sta = ACPI_STA_ALL;
+ }
+ }
+
+ return (unsigned int)sta;
+}
+
+static inline bool device_status_valid(unsigned int sta)
+{
+ /*
+ * ACPI spec says that _STA may return bit 0 clear with bit 3 set
+ * if the device is valid but does not require a device driver to be
+ * loaded (Section 6.3.7 of ACPI 5.0A).
+ */
+ unsigned int mask = ACPI_STA_DEVICE_ENABLED | ACPI_STA_DEVICE_FUNCTIONING;
+ return (sta & mask) == mask;
+}
+
+/**
+ * trim_stale_devices - remove PCI devices that are not responding.
+ * @dev: PCI device to start walking the hierarchy from.
+ */
+static void trim_stale_devices(struct pci_dev *dev)
+{
+ struct acpi_device *adev = ACPI_COMPANION(&dev->dev);
+ struct pci_bus *bus = dev->subordinate;
+ bool alive = dev->ignore_hotplug;
+
+ if (adev) {
+ acpi_status status;
+ unsigned long long sta;
+
+ status = acpi_evaluate_integer(adev->handle, "_STA", NULL, &sta);
+ alive = alive || (ACPI_SUCCESS(status) && device_status_valid(sta));
+ }
+ if (!alive)
+ alive = pci_device_is_present(dev);
+
+ if (!alive) {
+ pci_dev_set_disconnected(dev, NULL);
+ if (pci_has_subordinate(dev))
+ pci_walk_bus(dev->subordinate, pci_dev_set_disconnected,
+ NULL);
+
+ pci_stop_and_remove_bus_device(dev);
+ if (adev)
+ acpi_bus_trim(adev);
+ } else if (bus) {
+ struct pci_dev *child, *tmp;
+
+ /* The device is a bridge. so check the bus below it. */
+ pm_runtime_get_sync(&dev->dev);
+ list_for_each_entry_safe_reverse(child, tmp, &bus->devices, bus_list)
+ trim_stale_devices(child);
+
+ pm_runtime_put(&dev->dev);
+ }
+}
+
+/**
+ * acpiphp_check_bridge - re-enumerate devices
+ * @bridge: where to begin re-enumeration
+ *
+ * Iterate over all slots under this bridge and make sure that if a
+ * card is present they are enabled, and if not they are disabled.
+ */
+static void acpiphp_check_bridge(struct acpiphp_bridge *bridge)
+{
+ struct acpiphp_slot *slot;
+
+ /* Bail out if the bridge is going away. */
+ if (bridge->is_going_away)
+ return;
+
+ if (bridge->pci_dev)
+ pm_runtime_get_sync(&bridge->pci_dev->dev);
+
+ list_for_each_entry(slot, &bridge->slots, node) {
+ struct pci_bus *bus = slot->bus;
+ struct pci_dev *dev, *tmp;
+
+ if (slot_no_hotplug(slot)) {
+ ; /* do nothing */
+ } else if (device_status_valid(get_slot_status(slot))) {
+ /* remove stale devices if any */
+ list_for_each_entry_safe_reverse(dev, tmp,
+ &bus->devices, bus_list)
+ if (PCI_SLOT(dev->devfn) == slot->device)
+ trim_stale_devices(dev);
+
+ /* configure all functions */
+ enable_slot(slot, true);
+ } else {
+ disable_slot(slot);
+ }
+ }
+
+ if (bridge->pci_dev)
+ pm_runtime_put(&bridge->pci_dev->dev);
+}
+
+/*
+ * Remove devices for which we could not assign resources, call
+ * arch specific code to fix-up the bus
+ */
+static void acpiphp_sanitize_bus(struct pci_bus *bus)
+{
+ struct pci_dev *dev, *tmp;
+ int i;
+ unsigned long type_mask = IORESOURCE_IO | IORESOURCE_MEM;
+
+ list_for_each_entry_safe_reverse(dev, tmp, &bus->devices, bus_list) {
+ for (i = 0; i < PCI_BRIDGE_RESOURCES; i++) {
+ struct resource *res = &dev->resource[i];
+ if ((res->flags & type_mask) && !res->start &&
+ res->end) {
+ /* Could not assign a required resources
+ * for this device, remove it */
+ pci_stop_and_remove_bus_device(dev);
+ break;
+ }
+ }
+ }
+}
+
+/*
+ * ACPI event handlers
+ */
+
+void acpiphp_check_host_bridge(struct acpi_device *adev)
+{
+ struct acpiphp_bridge *bridge = NULL;
+
+ acpi_lock_hp_context();
+ if (adev->hp) {
+ bridge = to_acpiphp_root_context(adev->hp)->root_bridge;
+ if (bridge)
+ get_bridge(bridge);
+ }
+ acpi_unlock_hp_context();
+ if (bridge) {
+ pci_lock_rescan_remove();
+
+ acpiphp_check_bridge(bridge);
+
+ pci_unlock_rescan_remove();
+ put_bridge(bridge);
+ }
+}
+
+static int acpiphp_disable_and_eject_slot(struct acpiphp_slot *slot);
+
+static void hotplug_event(u32 type, struct acpiphp_context *context)
+{
+ acpi_handle handle = context->hp.self->handle;
+ struct acpiphp_func *func = &context->func;
+ struct acpiphp_slot *slot = func->slot;
+ struct acpiphp_bridge *bridge;
+
+ acpi_lock_hp_context();
+ bridge = context->bridge;
+ if (bridge)
+ get_bridge(bridge);
+
+ acpi_unlock_hp_context();
+
+ pci_lock_rescan_remove();
+
+ switch (type) {
+ case ACPI_NOTIFY_BUS_CHECK:
+ /* bus re-enumerate */
+ acpi_handle_debug(handle, "Bus check in %s()\n", __func__);
+ if (bridge)
+ acpiphp_check_bridge(bridge);
+ else if (!(slot->flags & SLOT_IS_GOING_AWAY))
+ enable_slot(slot, false);
+
+ break;
+
+ case ACPI_NOTIFY_DEVICE_CHECK:
+ /* device check */
+ acpi_handle_debug(handle, "Device check in %s()\n", __func__);
+ if (bridge) {
+ acpiphp_check_bridge(bridge);
+ } else if (!(slot->flags & SLOT_IS_GOING_AWAY)) {
+ /*
+ * Check if anything has changed in the slot and rescan
+ * from the parent if that's the case.
+ */
+ if (acpiphp_rescan_slot(slot))
+ acpiphp_check_bridge(func->parent);
+ }
+ break;
+
+ case ACPI_NOTIFY_EJECT_REQUEST:
+ /* request device eject */
+ acpi_handle_debug(handle, "Eject request in %s()\n", __func__);
+ acpiphp_disable_and_eject_slot(slot);
+ break;
+ }
+
+ pci_unlock_rescan_remove();
+ if (bridge)
+ put_bridge(bridge);
+}
+
+static int acpiphp_hotplug_notify(struct acpi_device *adev, u32 type)
+{
+ struct acpiphp_context *context;
+
+ context = acpiphp_grab_context(adev);
+ if (!context)
+ return -ENODATA;
+
+ hotplug_event(type, context);
+ acpiphp_let_context_go(context);
+ return 0;
+}
+
+/**
+ * acpiphp_enumerate_slots - Enumerate PCI slots for a given bus.
+ * @bus: PCI bus to enumerate the slots for.
+ *
+ * A "slot" is an object associated with a PCI device number. All functions
+ * (PCI devices) with the same bus and device number belong to the same slot.
+ */
+void acpiphp_enumerate_slots(struct pci_bus *bus)
+{
+ struct acpiphp_bridge *bridge;
+ struct acpi_device *adev;
+ acpi_handle handle;
+ acpi_status status;
+
+ if (acpiphp_disabled)
+ return;
+
+ adev = ACPI_COMPANION(bus->bridge);
+ if (!adev)
+ return;
+
+ handle = adev->handle;
+ bridge = kzalloc(sizeof(struct acpiphp_bridge), GFP_KERNEL);
+ if (!bridge)
+ return;
+
+ INIT_LIST_HEAD(&bridge->slots);
+ kref_init(&bridge->ref);
+ bridge->pci_dev = pci_dev_get(bus->self);
+ bridge->pci_bus = bus;
+
+ /*
+ * Grab a ref to the subordinate PCI bus in case the bus is
+ * removed via PCI core logical hotplug. The ref pins the bus
+ * (which we access during module unload).
+ */
+ get_device(&bus->dev);
+
+ acpi_lock_hp_context();
+ if (pci_is_root_bus(bridge->pci_bus)) {
+ struct acpiphp_root_context *root_context;
+
+ root_context = kzalloc(sizeof(*root_context), GFP_KERNEL);
+ if (!root_context)
+ goto err;
+
+ root_context->root_bridge = bridge;
+ acpi_set_hp_context(adev, &root_context->hp);
+ } else {
+ struct acpiphp_context *context;
+
+ /*
+ * This bridge should have been registered as a hotplug function
+ * under its parent, so the context should be there, unless the
+ * parent is going to be handled by pciehp, in which case this
+ * bridge is not interesting to us either.
+ */
+ context = acpiphp_get_context(adev);
+ if (!context)
+ goto err;
+
+ bridge->context = context;
+ context->bridge = bridge;
+ /* Get a reference to the parent bridge. */
+ get_bridge(context->func.parent);
+ }
+ acpi_unlock_hp_context();
+
+ /* Must be added to the list prior to calling acpiphp_add_context(). */
+ mutex_lock(&bridge_mutex);
+ list_add(&bridge->list, &bridge_list);
+ mutex_unlock(&bridge_mutex);
+
+ /* register all slot objects under this bridge */
+ status = acpi_walk_namespace(ACPI_TYPE_DEVICE, handle, 1,
+ acpiphp_add_context, NULL, bridge, NULL);
+ if (ACPI_FAILURE(status)) {
+ acpi_handle_err(handle, "failed to register slots\n");
+ cleanup_bridge(bridge);
+ put_bridge(bridge);
+ }
+ return;
+
+ err:
+ acpi_unlock_hp_context();
+ put_device(&bus->dev);
+ pci_dev_put(bridge->pci_dev);
+ kfree(bridge);
+}
+
+static void acpiphp_drop_bridge(struct acpiphp_bridge *bridge)
+{
+ if (pci_is_root_bus(bridge->pci_bus)) {
+ struct acpiphp_root_context *root_context;
+ struct acpi_device *adev;
+
+ acpi_lock_hp_context();
+ adev = ACPI_COMPANION(bridge->pci_bus->bridge);
+ root_context = to_acpiphp_root_context(adev->hp);
+ adev->hp = NULL;
+ acpi_unlock_hp_context();
+ kfree(root_context);
+ }
+ cleanup_bridge(bridge);
+ put_bridge(bridge);
+}
+
+/**
+ * acpiphp_remove_slots - Remove slot objects associated with a given bus.
+ * @bus: PCI bus to remove the slot objects for.
+ */
+void acpiphp_remove_slots(struct pci_bus *bus)
+{
+ struct acpiphp_bridge *bridge;
+
+ if (acpiphp_disabled)
+ return;
+
+ mutex_lock(&bridge_mutex);
+ list_for_each_entry(bridge, &bridge_list, list)
+ if (bridge->pci_bus == bus) {
+ mutex_unlock(&bridge_mutex);
+ acpiphp_drop_bridge(bridge);
+ return;
+ }
+
+ mutex_unlock(&bridge_mutex);
+}
+
+/**
+ * acpiphp_enable_slot - power on slot
+ * @slot: ACPI PHP slot
+ */
+int acpiphp_enable_slot(struct acpiphp_slot *slot)
+{
+ pci_lock_rescan_remove();
+
+ if (slot->flags & SLOT_IS_GOING_AWAY) {
+ pci_unlock_rescan_remove();
+ return -ENODEV;
+ }
+
+ /* configure all functions */
+ if (!(slot->flags & SLOT_ENABLED))
+ enable_slot(slot, false);
+
+ pci_unlock_rescan_remove();
+ return 0;
+}
+
+/**
+ * acpiphp_disable_and_eject_slot - power off and eject slot
+ * @slot: ACPI PHP slot
+ */
+static int acpiphp_disable_and_eject_slot(struct acpiphp_slot *slot)
+{
+ struct acpiphp_func *func;
+
+ if (slot->flags & SLOT_IS_GOING_AWAY)
+ return -ENODEV;
+
+ /* unconfigure all functions */
+ disable_slot(slot);
+
+ list_for_each_entry(func, &slot->funcs, sibling)
+ if (func->flags & FUNC_HAS_EJ0) {
+ acpi_handle handle = func_to_handle(func);
+
+ if (ACPI_FAILURE(acpi_evaluate_ej0(handle)))
+ acpi_handle_err(handle, "_EJ0 failed\n");
+
+ break;
+ }
+
+ return 0;
+}
+
+int acpiphp_disable_slot(struct acpiphp_slot *slot)
+{
+ int ret;
+
+ /*
+ * Acquire acpi_scan_lock to ensure that the execution of _EJ0 in
+ * acpiphp_disable_and_eject_slot() will be synchronized properly.
+ */
+ acpi_scan_lock_acquire();
+ pci_lock_rescan_remove();
+ ret = acpiphp_disable_and_eject_slot(slot);
+ pci_unlock_rescan_remove();
+ acpi_scan_lock_release();
+ return ret;
+}
+
+/*
+ * slot enabled: 1
+ * slot disabled: 0
+ */
+u8 acpiphp_get_power_status(struct acpiphp_slot *slot)
+{
+ return (slot->flags & SLOT_ENABLED);
+}
+
+/*
+ * latch open: 1
+ * latch closed: 0
+ */
+u8 acpiphp_get_latch_status(struct acpiphp_slot *slot)
+{
+ return !(get_slot_status(slot) & ACPI_STA_DEVICE_UI);
+}
+
+/*
+ * adapter presence : 1
+ * absence : 0
+ */
+u8 acpiphp_get_adapter_status(struct acpiphp_slot *slot)
+{
+ return !!get_slot_status(slot);
+}