Don't assume that only the driver would be accessing LNKCTL. ASPM policy changes can trigger write to LNKCTL outside of driver's control.

Use RMW capability accessors which do proper locking to avoid losing concurrent updates to the register value. On restore, clear the ASPMC field properly.

Fixes: e9603f4bdcc0 ("ath11k: pci: disable ASPM L0sLs before downloading firmware") Suggested-by: Lukas Wunner lukas@wunner.de Signed-off-by: Ilpo Järvinen ilpo.jarvinen@linux.intel.com Acked-by: Kalle Valo kvalo@kernel.org Cc: stable@vger.kernel.org --- drivers/net/wireless/ath/ath11k/pci.c | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/drivers/net/wireless/ath/ath11k/pci.c b/drivers/net/wireless/ath/ath11k/pci.c index 7b33731a50ee..6ba4cef6b1c7 100644 --- a/drivers/net/wireless/ath/ath11k/pci.c +++ b/drivers/net/wireless/ath/ath11k/pci.c @@ -581,8 +581,8 @@ static void ath11k_pci_aspm_disable(struct ath11k_pci *ab_pci) u16_get_bits(ab_pci->link_ctl, PCI_EXP_LNKCTL_ASPM_L1));

/* disable L0s and L1 */ - pcie_capability_write_word(ab_pci->pdev, PCI_EXP_LNKCTL, - ab_pci->link_ctl & ~PCI_EXP_LNKCTL_ASPMC); + pcie_capability_clear_word(ab_pci->pdev, PCI_EXP_LNKCTL, + PCI_EXP_LNKCTL_ASPMC);

set_bit(ATH11K_PCI_ASPM_RESTORE, &ab_pci->flags); } @@ -590,8 +590,10 @@ static void ath11k_pci_aspm_disable(struct ath11k_pci *ab_pci) static void ath11k_pci_aspm_restore(struct ath11k_pci *ab_pci) { if (test_and_clear_bit(ATH11K_PCI_ASPM_RESTORE, &ab_pci->flags)) - pcie_capability_write_word(ab_pci->pdev, PCI_EXP_LNKCTL, - ab_pci->link_ctl); + pcie_capability_clear_and_set_word(ab_pci->pdev, PCI_EXP_LNKCTL, + PCI_EXP_LNKCTL_ASPMC, + ab_pci->link_ctl & + PCI_EXP_LNKCTL_ASPMC); }

static int ath11k_pci_power_up(struct ath11k_base *ab)