ssize_t pci_read(uint8_t bus, uint8_t slot, uint8_t func, void *buffer, size_t count, size_t offset); ssize_t pci_write(uint8_t bus, uint8_t slot, uint8_t func, void *buffer, size_t count, size_t offset);
These syscalls attempts to read or write to and from the configuration space of a PCI device. All of the operations are blocking.
These syscalls returns the number of bytes operated on, or -1 on
failure. errno is to be set to:
EFAULT: The passed buffer is not accessible.
EINVAL: The passed device coordinates dont relate to a device.