pci_get_subsys(9)

📦 version 7.3.1, in nixpkgs unstable

🌸 NAME 🌸

okay bestie, welcome to the pci_get_subsys(9) page — this is the Kernel API Manual moment where we learn how to begin or continue searching for a PCI device by vendor/subvendor/device/subdevice id. iconic little lookup behavior, no cap 💅

✨ SYNOPSIS ✨

struct pci_dev * pci_get_subsys (unsigned int vendor , unsigned int
       device , unsigned int ss_vendor , unsigned int ss_device , struct
       pci_dev *from );

🎀 ARGUMENTS 🎀

  • vendor — the PCI vendor id you wanna match, or PCI_ANY_ID if you’re feeling “match all vendor ids” energy ✨
  • device — the PCI device id to match, or PCI_ANY_ID to match all device ids 🦋
  • ss_vendor — the PCI subsystem vendor id to match, or PCI_ANY_ID to match all vendor ids 💖
  • ss_device — the PCI subsystem device id to match, or PCI_ANY_ID to match all device ids 🌸
  • from — the previous PCI device found in the search, or NULL if you’re starting a brand-new search 👑

💫 DESCRIPTION 💫

So basically, this function iterates through the list of known PCI devices 🔥

If a PCI device is found with a matching vendor, device, ss_vendor, and ss_device, then a pointer to its device structure is returned, and the reference count to the device is incremented. slay. otherwise, NULL is returned 😭

A new search is initiated by passing NULL as the from argument. if from is not NULL, searches continue from the next device on the global list. and listen — the reference count for from is always decremented if it is not NULL. periodt 💅

bestie, this is the part where you remember: from is doing double duty as “where we left off” and “please clean up the old reference count.” very main character energy, but also very important 🙈

🦋 SEE ALSO 🦋

Kernel file ./drivers/pci/search.c — and the whole bestie lineup:

and that’s the whole vibe 🫶 this little page comes from ./drivers/pci, dated October 2026, and yes bestie, it’s the one and only pci_get_subsys(9) 💖✨🎀

📦 where this page comes from