pcibios_find_class(9) BIOS32 Functions pcibios_find_class(9)NAME
pcibios_find_class, pcibios_find_device - find a PCI class or device
SYNOPSIS
#include <linux/bios32.h>
int pcibios_find_class(unsigned int class_code, unsigned short index,
unsigned char* bus, unsigned char* device_fn);
int pcibios_find_device(unsigned short vendor,
unsigned short device_id ",unsigned short "index, unsigned char* bus,
unsigned char* device_fn);
DESCRIPTION
The pcibios_find_class function searches for a certain class of device
on the PCI bus. In this instance, class is used to represent a few
different categories of devices. Some examples are storage, network,
display, and memory classes. The classes are defined by the PCI Speci‐
fication, and the class_code is matched with the dword in the
configuration space of the device at offset 0x08.
The pcibios_find_device function finds a device on the PCI bus that has
the matching device and vendor ids. The vendor ids are assigned to the
PCI Sig to vendors, who in turn assign device ids to the devices they
develop. The vendor and device ids are encoded in dword 0x00 of the
configuration space.
Both pcibios_find_class and pcibios_find_device include an extra index
parameter, which is used to select the specific device if there are
multiple matches. An index of 0 matches the firts located board, 1 the
second, and so on.
The bus and device_fn parameters are PCI specific cookies that are
passed to other pcibios functions to access the configuration space of
the located device.
RETURN VALUE
On success, the functions return PCIBIOS_SUCCESSFUL. Otherwise, one of
the following error codes is returned:
PCIBIOS_DEVICE_NOT_FOUND
There is no device that matches the search criteria,
PCIBIOS_BAD_VENDOR_ID
The vendor id is invalid. (0xffff is not a valid id.)
PCIBIOS_FUNC_NOT_SUPPRTED
The PCI subsystem is not available
AVAILABILITY
Linux 1.0+
SEE ALSOpcibios_present(9)
/usr/include/linux/pci.h, /usr/include/linux/bios32.h
PCI Local Bus Specification
AUTHOR
Kirk Petersen (kirk@speakeasy.org)
BUGSLinux DDI August 5, 1997 pcibios_find_class(9)
