Hi,
let us assume you want to determine which driver is behind a device. For example disk /dev/sdc
By udev. Query the device /dev/sdc by udevadm. Scroll down to the section for the pci device
root@devdeb ~# udevadm info -a -n /dev/sdc
.....
looking at parent device '/devices/pci0000:00/0000:00:10.0':
KERNELS=="0000:00:10.0"
SUBSYSTEMS=="pci"
DRIVERS=="mptspi"
.....
or (the native way) by sysfs
root@devdeb ~# cd /sys/block/sdc
root@devdeb ~# cd -P /sys/block/sdc/device
/sys/devices/pci0000:00/0000:00:10.0/host2/target2:0:1/2:0:1:0
Go to the pci device
root@devdeb ~# cd /sys/devices/pci0000:00/0000:00:10.0
root@devdeb ~# ls -l driver
lrwxrwxrwx 1 root root 0 Dec 22 09:14 driver -> ../../../bus/pci/drivers/mptspi
Michael