pci_create_slot — create or increment refcount for physical PCI slot
struct pci_slot * pci_create_slot ( | struct pci_bus * parent, |
int slot_nr, | |
const char * name, | |
struct hotplug_slot * hotplug) ; |
parent
struct pci_bus of parent bridge
slot_nr
PCI_SLOT(pci_dev->devfn) or -1 for placeholder
name
user visible string presented in /sys/bus/pci/slots/<name>
hotplug
set if caller is hotplug driver, NULL otherwise
PCI slots have first class attributes such as address, speed, width, and a struct pci_slot is used to manage them. This interface will either return a new struct pci_slot to the caller, or if the pci_slot already exists, its refcount will be incremented.
Slots are uniquely identified by a pci_bus
, slot_nr
tuple.
There are known platforms with broken firmware that assign the same name to multiple slots. Workaround these broken platforms by renaming the slots on behalf of the caller. If firmware assigns name N to
The first slot is assigned N The second slot is assigned N-1 The third slot is assigned N-2 etc.
In most cases, pci_bus
, slot_nr
will be sufficient to uniquely identify
a slot. There is one notable exception - pSeries (rpaphp), where the
slot_nr
cannot be determined until a device is actually inserted into
the slot. In this scenario, the caller may pass -1 for slot_nr
.
The following semantics are imposed when the caller passes slot_nr
==
-1. First, we no longer check for an existing struct
pci_slot, as there
may be many slots with slot_nr
of -1. The other change in semantics is
user-visible, which is the 'address' parameter presented in sysfs will