pci_driver.probe function not called so pci_device_id wrong? - linux-kernel

Question

I am moving my first steps into Linux Kernel Device Driver development.
I learnt that for pci-e cards I have to call pci_register_driver providing information via an object of type pci_driver ( below an example ).
When I load my module ( via insmod ) If the information passed via .id_table is found than the .probe function is called.
As I am now I cannot see my .probe function called at all ( I added some logging via printk ) so I must assume that the information contained in pci_device_id must be wrong, right?
Is there any way to retrieve this information directly from the hardware itself?
Once I plug my PCI-E card on my Linux box, where I can find all information about it?
Maybe reading BIOS or some file in sys?
Any help is appreciated.
AFG
static struct pci_driver my_driver = {
// other here
.id_table = pci_datatable,
.probe = driver_add
//
};
static struct pci_device_id pci_datatable[] __devinitdata =
{
{ VendorID, PciExp_0041, PCI_ANY_ID, PCI_ANY_ID },
{ 0 },
};
int __devinit DmaDriverAdd(
struct pci_dev * pPciDev,
const struct pci_device_id * pPciEntry
)
{
// my stuff!
}

Answer 1

While the accepted answer does indeed answer the question, I want to elaborate a bit about the probe function not being called.
According to the Documentation/PCI/pci.txt (How To Write Linux PCI Drivers) the probing function is called for all existing PCI devices that are not owned by the other drivers yet. So, even if you have the correct vendor and device IDs you will not see the function being called if the device is owned by another driver.
To see which drivers own which devices run:
lspci -knn
If you temporarily change both vendor ID and device ID to PCI_ANY_ID your probe function will be called for every available (i.e. not owned) device.

Answer 2

The command you want is lspci.
With no arguments it will give you a list of all PCI devices, eg:
$ lspci
00:00.0 Host bridge: Intel Corporation 2nd Generation Core Processor Family DRAM Controller (rev 09)
00:02.0 VGA compatible controller: Intel Corporation 2nd Generation Core Processor Family
03:00.0 Network controller: Intel Corporation Centrino Advanced-N 6205 (rev 34)
...
Then to get the ids, use:
$ lspci -v -n -s 03:00.0
03:00.0 0280: 8086:0085 (rev 34)
Subsystem: 8086:1311
Flags: bus master, fast devsel, latency 0, IRQ 52
You can also find the same information in /sys:
$ cd /sys/bus/pci/devices/0000:03:00.0
$ cat vendor device
0x8086
0x0085
$ cat subsystem_vendor subsystem_device
0x8086
0x1311