PCI: Avoid SBR for Qualcomm WCN6855/WCN7850 WiFi, SDX62/SDX65 modems

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Some Qualcomm PCIe devices (WCN6855/WCN7850 WiFi cards, SDX62/SDX65 modems)
do not properly support Secondary Bus Reset (SBR).

Testing confirms this is device-specific, not deployment-specific:
MediaTek MT7925e successfully uses bus reset through the same passive
M.2-to-PCIe adapters where Qualcomm devices fail, proving PERST# is
properly wired through the adapters.

Prevent use of Secondary Bus Reset for these devices.

Signed-off-by: Jose Ignacio Tornos Martinez <jtornosm@redhat.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Link: https://lore.kernel.org/all/20260609163649.319755-4-jtornosm@redhat.com

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Jose Ignacio Tornos Martinez 2026-06-03 12:58:53 +02:00 • committed by Bjorn Helgaas

parent 9f22b92259

commit 6a4f64c3a3

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drivers/pci/quirks.c

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