[PATCH 0/2] PCI: of: Skip config reads for disabled bridges

[Xilin Wu]

Hi,

This series extracts the PCI change from the Radxa Dragon Q8B board
support series for review and application through the PCI tree, as
requested by Manivannan Sadhasivam.

The TC9563 PCI power-control driver powers off downstream ports marked
disabled in the device tree. Probing these port functions on the Dragon
Q8B causes a Completion Timeout, which the Root Complex reports as an AXI
bus error, triggering an Arm SError and preventing boot. The Root Port
to switch upstream link remains up, so a config-access blocker triggered
by Root Port link-down does not address this case.

Patch 1 corrects the stale return value documentation for
pci_set_of_node(). Patch 2 skips Vendor ID reads for unavailable
DT-described PCI bridges before any config access. Disabled endpoints
remain discoverable so that PCI fixups can run, with driver binding
suppressed as before.

Compared with the PCI patch in the original board support series:
- Split the unrelated kernel-doc correction into a separate patch.
- Explain the Completion Timeout and SError path in the commit message.
- Retain the generic PCI implementation, since the issue is not specific
  to Qualcomm hosts.

The functional change is required by the Dragon Q8B device tree, but this
series has no dependency on the board or display patches.

Previous posting:
https://lore.kernel.org/all/20260901-q8b-dts-v1-1-7de0b6a73d08@xxxxxxxxx/
Review discussion:
https://lore.kernel.org/all/fsrr5xg4plfknfcvv5co4ciklz5pywa5bbfxbthwsnjevysr5v@myghuxblnend/
https://lore.kernel.org/all/r22to3joold7ugzwolni4qahyumcekbyugrl2bms3xmiysqtgo@hu5s3dnyqwsj/

Signed-off-by: Xilin Wu <sophon@xxxxxxxxx>
---
Xilin Wu (2):
      PCI: of: Correct pci_set_of_node() return value documentation
      PCI: of: Avoid config reads for disabled bridge nodes

 drivers/pci/of.c    | 27 +++++++++++++++++++++++++--
 drivers/pci/pci.h   |  5 +++++
 drivers/pci/probe.c |  5 +++++
 3 files changed, 35 insertions(+), 2 deletions(-)
---
base-commit: cee9395acd8043be0644b25c34bfa86623f2b935
change-id: 20261009-pci-of-disabled-bridges-8406f7c92de2

Best regards,
--  
Xilin Wu <sophon@xxxxxxxxx>