[PATCH] acpi bridge hotadd: ACPI based root bridge hot-add

When you hot-plug a (root) bridge hierarchy, it may have p2p bridges and
devices attached to it that have not been configured by firmware.  In this
case, we need to configure the devices before starting them.  This patch
separates device start from device scan so that we can introduce the
configuration step in the middle.

I kept the existing semantics for pci_scan_bus() since there are a huge number
of callers to that function.

Also, I have no way of testing the changes I made to the parisc files, so this
needs review by those folks.  Sorry for the massive cross-post, this touches
files in many different places.

Signed-off-by: Rajesh Shah <rajesh.shah@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

4 files changed, 6 insertions, 2 deletions

diff --git a/arch/i386/pci/common.c b/arch/i386/pci/common.c
index 2a2e79fbfef8..87325263cd4f 100644
--- a/arch/i386/pci/common.c
+++ b/arch/i386/pci/common.c
@@ -134,7 +134,7 @@ struct pci_bus * __devinit pcibios_scan_root(int busnum)
 
         printk("PCI: Probing PCI hardware (bus %02x)\n", busnum);
 
-        return pci_scan_bus(busnum, &pci_root_ops, NULL);
+        return pci_scan_bus_parented(NULL, busnum, &pci_root_ops, NULL);
 }
 
 extern u8 pci_cache_line_size;
diff --git a/arch/i386/pci/legacy.c b/arch/i386/pci/legacy.c
index 1492e3753869..149a9588c256 100644
--- a/arch/i386/pci/legacy.c
+++ b/arch/i386/pci/legacy.c
@@ -45,6 +45,8 @@ static int __init pci_legacy_init(void)
 
         printk("PCI: Probing PCI hardware\n");
         pci_root_bus = pcibios_scan_root(0);
+        if (pci_root_bus)
+                pci_bus_add_devices(pci_root_bus);
 
         pcibios_fixup_peer_bridges();
 
diff --git a/arch/i386/pci/numa.c b/arch/i386/pci/numa.c
index 9e3695461899..adbe17a38f6f 100644
--- a/arch/i386/pci/numa.c
+++ b/arch/i386/pci/numa.c
@@ -115,6 +115,8 @@ static int __init pci_numa_init(void)
                 return 0;
 
         pci_root_bus = pcibios_scan_root(0);
+        if (pci_root_bus)
+                pci_bus_add_devices(pci_root_bus);
         if (num_online_nodes() > 1)
                 for_each_online_node(quad) {
                         if (quad == 0)
diff --git a/arch/ia64/pci/pci.c b/arch/ia64/pci/pci.c
index e3fc4edea113..c0661d3382e4 100644
--- a/arch/ia64/pci/pci.c
+++ b/arch/ia64/pci/pci.c
@@ -312,7 +312,7 @@ pci_acpi_scan_root(struct acpi_device *device, int domain, int bus)
         acpi_walk_resources(device->handle, METHOD_NAME__CRS, add_window,
                         &info);
 
-        pbus = pci_scan_bus(bus, &pci_root_ops, controller);
+        pbus = pci_scan_bus_parented(NULL, bus, &pci_root_ops, controller);
         if (pbus)
                 pcibios_setup_root_windows(pbus, controller);