From: Victor Gu <xigu@xxxxxxxxxxx> The PCI configuration space read/write functions were special casing the situation where PCI_SLOT(devfn) != 0, and returned PCIBIOS_DEVICE_NOT_FOUND in this case. However, will this is what is intended for the root bus, it is not intended for the child busses, as it prevents discovering devices with PCI_SLOT(x) != 0. Therefore, we return PCIBIOS_DEVICE_NOT_FOUND only if we're on the root bus. Fixes: 8c39d710363c1 ("PCI: aardvark: Add Aardvark PCI host controller driver") Cc: <stable@xxxxxxxxxxxxxxx> Signed-off-by: Victor Gu <xigu@xxxxxxxxxxx> Reviewed-by: Wilson Ding <dingwei@xxxxxxxxxxx> Reviewed-by: Nadav Haklai <nadavh@xxxxxxxxxxx> [Thomas: tweak commit log.] Signed-off-by: Thomas Petazzoni <thomas.petazzoni@xxxxxxxxxxxxxxxxxx> --- drivers/pci/host/pci-aardvark.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/pci/host/pci-aardvark.c b/drivers/pci/host/pci-aardvark.c index 5fb9b620ac78..582d75f864e3 100644 --- a/drivers/pci/host/pci-aardvark.c +++ b/drivers/pci/host/pci-aardvark.c @@ -441,7 +441,7 @@ static int advk_pcie_rd_conf(struct pci_bus *bus, u32 devfn, u32 reg; int ret; - if (PCI_SLOT(devfn) != 0) { + if ((bus->number == pcie->root_bus_nr) && (PCI_SLOT(devfn) != 0)) { *val = 0xffffffff; return PCIBIOS_DEVICE_NOT_FOUND; } @@ -495,7 +495,7 @@ static int advk_pcie_wr_conf(struct pci_bus *bus, u32 devfn, int offset; int ret; - if (PCI_SLOT(devfn) != 0) + if ((bus->number == pcie->root_bus_nr) && (PCI_SLOT(devfn) != 0)) return PCIBIOS_DEVICE_NOT_FOUND; if (where % size) -- 2.13.5