diff options
Diffstat (limited to 'drivers/pci/hotplug/acpiphp_glue.c')
| -rw-r--r-- | drivers/pci/hotplug/acpiphp_glue.c | 1060 |
1 files changed, 1060 insertions, 0 deletions
diff --git a/drivers/pci/hotplug/acpiphp_glue.c b/drivers/pci/hotplug/acpiphp_glue.c new file mode 100644 index 000000000..6efa3d8db --- /dev/null +++ b/drivers/pci/hotplug/acpiphp_glue.c @@ -0,0 +1,1060 @@ +// 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; + + 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); +} |