On failure pcie_capability_read_dword() sets it's last parameter, val
to 0. However, with Patch 12/12, it is possible that val is set to ~0
on failure. This would introduce a bug because (x & x) == (~0 & x).

Since ~0 is an invalid value here,

Add an extra check for ~0 to the if condition to ensure success.

Suggested-by: Bjorn Helgaas <bj...@helgaas.com>
Signed-off-by: Saheed O. Bolarinwa <refactormys...@gmail.com>
---
 drivers/net/wireless/ath/ath9k/pci.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/net/wireless/ath/ath9k/pci.c 
b/drivers/net/wireless/ath/ath9k/pci.c
index f3461b193c7a..f02b243befef 100644
--- a/drivers/net/wireless/ath/ath9k/pci.c
+++ b/drivers/net/wireless/ath/ath9k/pci.c
@@ -867,7 +867,8 @@ static void ath_pci_aspm_init(struct ath_common *common)
                pci_read_config_dword(pdev, 0x70c, &ah->config.aspm_l1_fix);
 
        pcie_capability_read_word(parent, PCI_EXP_LNKCTL, &aspm);
-       if (aspm & (PCI_EXP_LNKCTL_ASPM_L0S | PCI_EXP_LNKCTL_ASPM_L1)) {
+       if ((aspm != (u16)~0) &&
+           (aspm & (PCI_EXP_LNKCTL_ASPM_L0S | PCI_EXP_LNKCTL_ASPM_L1))) {
                ah->aspm_enabled = true;
                /* Initialize PCIe PM and SERDES registers. */
                ath9k_hw_configpcipowersave(ah, false);
-- 
2.18.4

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