1 files changed, 62 insertions, 29 deletions

diff --git a/drivers/pci/hotplug/acpiphp_glue.c b/drivers/pci/hotplug/acpiphp_glue.c
index 21a6269501e1..e2e5e3088816 100644
--- a/drivers/pci/hotplug/acpiphp_glue.c
+++ b/drivers/pci/hotplug/acpiphp_glue.c
@@ -46,6 +46,7 @@
 #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>
@@ -687,47 +688,75 @@ static unsigned int get_slot_status(struct acpiphp_slot *slot)
 }
 
 /**
+ * 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)
+{
+        acpi_handle handle = ACPI_HANDLE(&dev->dev);
+        struct pci_bus *bus = dev->subordinate;
+        bool alive = false;
+
+        if (handle) {
+                acpi_status status;
+                unsigned long long sta;
+
+                status = acpi_evaluate_integer(handle, "_STA", NULL, &sta);
+                alive = ACPI_SUCCESS(status) && sta == ACPI_STA_ALL;
+        }
+        if (!alive) {
+                u32 v;
+
+                /* Check if the device responds. */
+                alive = pci_bus_read_dev_vendor_id(dev->bus, dev->devfn, &v, 0);
+        }
+        if (!alive) {
+                pci_stop_and_remove_bus_device(dev);
+                if (handle)
+                        acpiphp_bus_trim(handle);
+        } 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(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 int acpiphp_check_bridge(struct acpiphp_bridge *bridge)
+static void acpiphp_check_bridge(struct acpiphp_bridge *bridge)
 {
         struct acpiphp_slot *slot;
-        int retval = 0;
-        int enabled, disabled;
-
-        enabled = disabled = 0;
 
         list_for_each_entry(slot, &bridge->slots, node) {
-                unsigned int status = get_slot_status(slot);
-                if (slot->flags & SLOT_ENABLED) {
-                        if (status == ACPI_STA_ALL)
-                                continue;
-
-                        retval = acpiphp_disable_and_eject_slot(slot);
-                        if (retval)
-                                goto err_exit;
-
-                        disabled++;
+                struct pci_bus *bus = slot->bus;
+                struct pci_dev *dev, *tmp;
+
+                mutex_lock(&slot->crit_sect);
+                /* wake up all functions */
+                if (get_slot_status(slot) == ACPI_STA_ALL) {
+                        /* remove stale devices if any */
+                        list_for_each_entry_safe(dev, tmp, &bus->devices,
+                                                 bus_list)
+                                if (PCI_SLOT(dev->devfn) == slot->device)
+                                        trim_stale_devices(dev);
+
+                        /* configure all functions */
+                        enable_device(slot);
                 } else {
-                        if (status != ACPI_STA_ALL)
-                                continue;
-                        retval = acpiphp_enable_slot(slot);
-                        if (retval) {
-                                err("Error occurred in enabling\n");
-                                goto err_exit;
-                        }
-                        enabled++;
+                        disable_device(slot);
                 }
+                mutex_unlock(&slot->crit_sect);
         }
-
-        dbg("%s: %d enabled, %d disabled\n", __func__, enabled, disabled);
-
- err_exit:
-        return retval;
 }
 
 static void acpiphp_set_hpp_values(struct pci_bus *bus)
@@ -828,7 +857,11 @@ static void hotplug_event(acpi_handle handle, u32 type, void *data)
                                             ACPI_UINT32_MAX, check_sub_bridges,
                                             NULL, NULL, NULL);
                 } else {
-                        acpiphp_enable_slot(func->slot);
+                        struct acpiphp_slot *slot = func->slot;
+
+                        mutex_lock(&slot->crit_sect);
+                        enable_device(slot);
+                        mutex_unlock(&slot->crit_sect);
                 }
                 break;