Linux Device Drivers, Second Edition

Quick Reference

This section, as usual, summarizes the symbols introduced in the chapter.

#include <linux/config.h> , CONFIG_PCI

This macro should be used to conditionally compile PCI-related code. When a PCI module is loaded to a non-PCI kernel, insmod complains about several symbols being unresolved.

#include <linux/pci.h>

This header includes symbolic names for the PCI registers and several vendor and device ID values.

int pci_present(void);

This function returns a boolean value that tells whether the computer we’re running on has PCI capabilities or not.

struct pci_dev; , struct pci_bus; , struct pci_driver; , struct pci_device_id;

These structures represent the objects involved in PCI management. The concept of pci_driver is new as of Linux 2.4, and struct pci_device_id is central to it.

struct pci_dev *pci_find_device(unsigned int vendor, unsigned int device, struct pci_dev *from); , struct pci_dev *pci_find_class(unsigned int class, struct pci_dev *from);

These functions are used to look up the device list looking for devices with a specific signature or belonging to a specific class. The return value is NULL if none is found. from is used to continue a search; it must be NULL the first time you call either function, and it must point to the device just found if you are searching for more devices.

int pci_read_config_byte(struct pci_dev *dev, int where, u8 *val); , int pci_read_config_word(struct pci_dev *dev, int where, u16 *val); , int pci_read_config_dword(struct ...