PCI Hotplug: acpiphp: find bridges the easy way

Instead of constantly evaluating _ADR and _SEG over and over again,
let's simplify our lives by using:

	acpi_pci_find_root() for root bridges
	acpi_get_pci_dev() for p2p bridges

This change eliminates some copy 'n paste code and also allows us
to simplify some internal interfaces.

Reviewed-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Tested-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Cc: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>

1 files changed, 21 insertions, 60 deletions

diff --git a/drivers/pci/hotplug/acpiphp_glue.c b/drivers/pci/hotplug/acpiphp_glue.c
index 2e5f25969e11..e72e0adc0681 100644
--- a/drivers/pci/hotplug/acpiphp_glue.c
+++ b/drivers/pci/hotplug/acpiphp_glue.c
@@ -277,14 +277,15 @@ register_slot(acpi_handle handle, u32 lvl, void *context, void **rv)
 
 
 /* see if it's worth looking at this bridge */
-static int detect_ejectable_slots(struct pci_bus *pbus)
+static int detect_ejectable_slots(acpi_handle handle)
 {
-        int found = acpi_pci_detect_ejectable(pbus);
+        int found;
+        struct pci_bus *pbus;
+
+        pbus = pci_bus_from_handle(handle);
+        found = acpi_pci_detect_ejectable(pbus);
         if (!found) {
-                acpi_handle bridge_handle = acpi_pci_get_bridge_handle(pbus);
-                if (!bridge_handle)
-                        return 0;
-                acpi_walk_namespace(ACPI_TYPE_DEVICE, bridge_handle, (u32)1,
+                acpi_walk_namespace(ACPI_TYPE_DEVICE, handle, (u32)1,
                                     is_pci_dock_device, (void *)&found, NULL);
         }
         return found;
@@ -415,9 +416,10 @@ static inline void config_p2p_bridge_flags(struct acpiphp_bridge *bridge)
 
 
 /* allocate and initialize host bridge data structure */
-static void add_host_bridge(acpi_handle *handle, struct pci_bus *pci_bus)
+static void add_host_bridge(acpi_handle *handle)
 {
         struct acpiphp_bridge *bridge;
+        struct acpi_pci_root *root = acpi_pci_find_root(handle);
 
         bridge = kzalloc(sizeof(struct acpiphp_bridge), GFP_KERNEL);
         if (bridge == NULL)
@@ -426,7 +428,7 @@ static void add_host_bridge(acpi_handle *handle, struct pci_bus *pci_bus)
         bridge->type = BRIDGE_TYPE_HOST;
         bridge->handle = handle;
 
-        bridge->pci_bus = pci_bus;
+        bridge->pci_bus = root->bus;
 
         spin_lock_init(&bridge->res_lock);
 
@@ -435,7 +437,7 @@ static void add_host_bridge(acpi_handle *handle, struct pci_bus *pci_bus)
 
 
 /* allocate and initialize PCI-to-PCI bridge data structure */
-static void add_p2p_bridge(acpi_handle *handle, struct pci_dev *pci_dev)
+static void add_p2p_bridge(acpi_handle *handle)
 {
         struct acpiphp_bridge *bridge;
 
@@ -449,8 +451,8 @@ static void add_p2p_bridge(acpi_handle *handle, struct pci_dev *pci_dev)
         bridge->handle = handle;
         config_p2p_bridge_flags(bridge);
 
-        bridge->pci_dev = pci_dev_get(pci_dev);
-        bridge->pci_bus = pci_dev->subordinate;
+        bridge->pci_dev = acpi_get_pci_dev(handle);
+        bridge->pci_bus = bridge->pci_dev->subordinate;
         if (!bridge->pci_bus) {
                 err("This is not a PCI-to-PCI bridge!\n");
                 goto err;
@@ -467,7 +469,7 @@ static void add_p2p_bridge(acpi_handle *handle, struct pci_dev *pci_dev)
         init_bridge_misc(bridge);
         return;
  err:
-        pci_dev_put(pci_dev);
+        pci_dev_put(bridge->pci_dev);
         kfree(bridge);
         return;
 }
@@ -478,39 +480,21 @@ static acpi_status
 find_p2p_bridge(acpi_handle handle, u32 lvl, void *context, void **rv)
 {
         acpi_status status;
-        acpi_handle dummy_handle;
-        unsigned long long tmp;
-        int device, function;
         struct pci_dev *dev;
-        struct pci_bus *pci_bus = context;
-
-        status = acpi_get_handle(handle, "_ADR", &dummy_handle);
-        if (ACPI_FAILURE(status))
-                return AE_OK;           /* continue */
-
-        status = acpi_evaluate_integer(handle, "_ADR", NULL, &tmp);
-        if (ACPI_FAILURE(status)) {
-                dbg("%s: _ADR evaluation failure\n", __func__);
-                return AE_OK;
-        }
-
-        device = (tmp >> 16) & 0xffff;
-        function = tmp & 0xffff;
-
-        dev = pci_get_slot(pci_bus, PCI_DEVFN(device, function));
 
+        dev = acpi_get_pci_dev(handle);
         if (!dev || !dev->subordinate)
                 goto out;
 
         /* check if this bridge has ejectable slots */
-        if ((detect_ejectable_slots(dev->subordinate) > 0)) {
+        if ((detect_ejectable_slots(handle) > 0)) {
                 dbg("found PCI-to-PCI bridge at PCI %s\n", pci_name(dev));
-                add_p2p_bridge(handle, dev);
+                add_p2p_bridge(handle);
         }
 
         /* search P2P bridges under this p2p bridge */
         status = acpi_walk_namespace(ACPI_TYPE_DEVICE, handle, (u32)1,
-                                     find_p2p_bridge, dev->subordinate, NULL);
+                                     find_p2p_bridge, NULL, NULL);
         if (ACPI_FAILURE(status))
                 warn("find_p2p_bridge failed (error code = 0x%x)\n", status);
 
@@ -525,9 +509,7 @@ static int add_bridge(acpi_handle handle)
 {
         acpi_status status;
         unsigned long long tmp;
-        int seg, bus;
         acpi_handle dummy_handle;
-        struct pci_bus *pci_bus;
 
         /* if the bridge doesn't have _STA, we assume it is always there */
         status = acpi_get_handle(handle, "_STA", &dummy_handle);
@@ -542,36 +524,15 @@ static int add_bridge(acpi_handle handle)
                         return 0;
         }
 
-        /* get PCI segment number */
-        status = acpi_evaluate_integer(handle, "_SEG", NULL, &tmp);
-
-        seg = ACPI_SUCCESS(status) ? tmp : 0;
-
-        /* get PCI bus number */
-        status = acpi_evaluate_integer(handle, "_BBN", NULL, &tmp);
-
-        if (ACPI_SUCCESS(status)) {
-                bus = tmp;
-        } else {
-                warn("can't get bus number, assuming 0\n");
-                bus = 0;
-        }
-
-        pci_bus = pci_find_bus(seg, bus);
-        if (!pci_bus) {
-                err("Can't find bus %04x:%02x\n", seg, bus);
-                return 0;
-        }
-
         /* check if this bridge has ejectable slots */
-        if (detect_ejectable_slots(pci_bus) > 0) {
+        if (detect_ejectable_slots(handle) > 0) {
                 dbg("found PCI host-bus bridge with hot-pluggable slots\n");
-                add_host_bridge(handle, pci_bus);
+                add_host_bridge(handle);
         }
 
         /* search P2P bridges under this host bridge */
         status = acpi_walk_namespace(ACPI_TYPE_DEVICE, handle, (u32)1,
-                                     find_p2p_bridge, pci_bus, NULL);
+                                     find_p2p_bridge, NULL, NULL);
 
         if (ACPI_FAILURE(status))
                 warn("find_p2p_bridge failed (error code = 0x%x)\n", status);