PCI: aardvark: Indicate error in 'val' when config read fails

commit b1bd5714472cc72e14409f5659b154c765a76c65 upstream.

Most callers of config read do not check for return value. But most of the
ones that do, checks for error indication in 'val' variable.

This patch updates error handling in advk_pcie_rd_conf() function. If PIO
transfer fails then 'val' variable is set to 0xffffffff which indicates
failture.

Link: https://lore.kernel.org/r/20200528162604.GA323482@bjorn-Precision-5520
Link: https://lore.kernel.org/r/20200601130315.18895-1-pali@kernel.org
Reported-by: Bjorn Helgaas <helgaas@kernel.org>
Signed-off-by: Pali Rohár <pali@kernel.org>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/pci/controller/pci-aardvark.c b/drivers/pci/controller/pci-aardvark.c
index 0538348ed843f483479e017fed77fd0ff270de50..a957211930a8115d83c611c30505de1c0b0b306e 100644 (file)
--- a/drivers/pci/controller/pci-aardvark.c
+++ b/drivers/pci/controller/pci-aardvark.c
@@ -664,8 +664,10 @@ static int advk_pcie_rd_conf(struct pci_bus *bus, u32 devfn,
        advk_writel(pcie, 1, PIO_START);
 
        ret = advk_pcie_wait_pio(pcie);
-       if (ret < 0)
+       if (ret < 0) {
+               *val = 0xffffffff;
                return PCIBIOS_SET_FAILED;
+       }
 
        /* Check PIO status and get the read result */
        ret = advk_pcie_check_pio_status(pcie, val);