pdev
res_name
Mark all PCI regions associated with PCI device pdev as being reserved by owner res_name. Do not access any address inside the PCI regions unless this call returns successfully.
pci_request_regions_exclusive will mark the region so that /dev/mem and the sysfs MMIO access will not be allowed.
Returns 0 on success, or EBUSY on error. A warning message is also printed on failure.