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: Marek Behún <kabel@kernel.org>
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 aaeb1c78076c02917ca92d372655d2b756a1c339..5837fff32f8e2802919a68b40cd12f236773dfda 100644 (file)
--- a/drivers/pci/controller/pci-aardvark.c
+++ b/drivers/pci/controller/pci-aardvark.c
@@ -596,8 +596,10 @@ 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);