PCI: aardvark: Fix logic in advk_pcie_{rd,wr}_conf()

BugLink: http://bugs.launchpad.net/bugs/1778265
commit 660661afcd40ed7f515ef3369721ed58e80c0fc5 upstream.

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, while 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@vger.kernel.org>
Signed-off-by: Victor Gu <xigu@marvell.com>
Reviewed-by: Wilson Ding <dingwei@marvell.com>
Reviewed-by: Nadav Haklai <nadavh@marvell.com>
[Thomas: tweak commit log.]
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Kamal Mostafa <kamal@canonical.com>
Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>

diff --git a/drivers/pci/host/pci-aardvark.c b/drivers/pci/host/pci-aardvark.c
index 26ed0c08f20972e6d1d6ef09b4daf140dc17a193..3e7d1e22d33e1acdca6652b35f5871edf0146d29 100644 (file)
--- a/drivers/pci/host/pci-aardvark.c
+++ b/drivers/pci/host/pci-aardvark.c
@@ -440,7 +440,7 @@ 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;
        }
@@ -494,7 +494,7 @@ 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)