From: Ilpo Järvinen Date: Mon, 17 Jul 2023 12:05:01 +0000 (+0300) Subject: wifi: ath12k: Use RMW accessors for changing LNKCTL X-Git-Tag: v6.4.16~277 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=f8dca9806d703def20adaed0ec97a4678f46d72b;p=thirdparty%2Fkernel%2Fstable.git wifi: ath12k: Use RMW accessors for changing LNKCTL [ Upstream commit f5a7ac118faf6d4f794975947b3300717eae8fc5 ] 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. Suggested-by: Lukas Wunner Fixes: d889913205cf ("wifi: ath12k: driver for Qualcomm Wi-Fi 7 devices") Link: https://lore.kernel.org/r/20230717120503.15276-10-ilpo.jarvinen@linux.intel.com Signed-off-by: Ilpo Järvinen Signed-off-by: Bjorn Helgaas Reviewed-by: Simon Horman Acked-by: Kalle Valo Signed-off-by: Sasha Levin --- diff --git a/drivers/net/wireless/ath/ath12k/pci.c b/drivers/net/wireless/ath/ath12k/pci.c index 9f174daf324c9..e1e45eb50f3e3 100644 --- a/drivers/net/wireless/ath/ath12k/pci.c +++ b/drivers/net/wireless/ath/ath12k/pci.c @@ -794,8 +794,8 @@ static void ath12k_pci_aspm_disable(struct ath12k_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(ATH12K_PCI_ASPM_RESTORE, &ab_pci->flags); } @@ -803,8 +803,10 @@ static void ath12k_pci_aspm_disable(struct ath12k_pci *ab_pci) static void ath12k_pci_aspm_restore(struct ath12k_pci *ab_pci) { if (test_and_clear_bit(ATH12K_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 void ath12k_pci_kill_tasklets(struct ath12k_base *ab)