PCI: pciehp: Rename duplicate slot name N as N-1, N-2, N-M...

Commit 3800345f723fd130d50434d4717b99d4a9f383c8 (pciehp: fix slot name)
introduces the pciehp_slot_with_bus module parameter, which was intended
to help work around broken firmware that assigns the same name to multiple
slots.

Commit 9e4f2e8d4ddb04ad16a3828cd9a369a5a5287009 (pciehp: add message about
pciehp_slot_with_bus option) tells the user to use the above parameter
in the event of a name collision.

This approach is sub-optimal because it requires too much work from
the user.

Instead, let's rename the slot on behalf of the user. If firmware
assigns the name N to multiple slots, then:

	The first registered slot is assigned N
	The second registered slot is assigned N-1
	The third registered slot is assigned N-2
	The Mth registered slot becomes N-M

In the event we overflow the slot->name parameter, we report an
error to the user.

This is a temporary fix until the entire PCI core can be reworked
such that individual drivers no longer have to manage their own
slot names.

Tested-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Acked-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>

1 files changed, 1 insertions, 10 deletions

diff --git a/drivers/pci/hotplug/pciehp_hpc.c b/drivers/pci/hotplug/pciehp_hpc.c
index ad27e9e225a6..ab31f5ba665d 100644
--- a/drivers/pci/hotplug/pciehp_hpc.c
+++ b/drivers/pci/hotplug/pciehp_hpc.c
@@ -1030,15 +1030,6 @@ static void pcie_shutdown_notification(struct controller *ctrl)
         pciehp_free_irq(ctrl);
 }
 
-static void make_slot_name(struct slot *slot)
-{
-        if (pciehp_slot_with_bus)
-                snprintf(slot->name, SLOT_NAME_SIZE, "%04d_%04d",
-                         slot->bus, slot->number);
-        else
-                snprintf(slot->name, SLOT_NAME_SIZE, "%d", slot->number);
-}
-
 static int pcie_init_slot(struct controller *ctrl)
 {
         struct slot *slot;
@@ -1053,7 +1044,7 @@ static int pcie_init_slot(struct controller *ctrl)
         slot->device = ctrl->slot_device_offset + slot->hp_slot;
         slot->hpc_ops = ctrl->hpc_ops;
         slot->number = ctrl->first_slot;
-        make_slot_name(slot);
+        snprintf(slot->name, SLOT_NAME_SIZE, "%d", slot->number);
         mutex_init(&slot->lock);
         INIT_DELAYED_WORK(&slot->work, pciehp_queue_pushbutton_work);
         list_add(&slot->slot_list, &ctrl->slot_list);