diff mbox series

[09/17] wifi: ath9k: Use pcie_lnkctl_clear_and_set() for changing LNKCTL

Message ID 20230511131441.45704-10-ilpo.jarvinen@linux.intel.com
State New
Headers show
Series PCI: Improve LNKCTL & LNKCTL2 concurrency control | expand

Commit Message

Ilpo Järvinen May 11, 2023, 1:14 p.m. UTC 
Don't assume that only the driver would be accessing LNKCTL. ASPM
policy changes can trigger write to LNKCTL outside of driver's control.
And in the case of upstream (parent), the driver does not even own the
device it's changing LNKCTL for.

Use pcie_lnkctl_clear_and_set() which does proper locking to avoid
losing concurrent updates to the register value.

Suggested-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
---
 drivers/net/wireless/ath/ath9k/pci.c | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)
diff mbox series

Patch

diff --git a/drivers/net/wireless/ath/ath9k/pci.c b/drivers/net/wireless/ath/ath9k/pci.c
index a09f9d223f3d..c2130fe6c9e6 100644
--- a/drivers/net/wireless/ath/ath9k/pci.c
+++ b/drivers/net/wireless/ath/ath9k/pci.c
@@ -837,15 +837,16 @@  static void ath_pci_aspm_init(struct ath_common *common)
 	if ((ath9k_hw_get_btcoex_scheme(ah) != ATH_BTCOEX_CFG_NONE) &&
 	    (AR_SREV_9285(ah))) {
 		/* Bluetooth coexistence requires disabling ASPM. */
-		pcie_capability_clear_word(pdev, PCI_EXP_LNKCTL,
-			PCI_EXP_LNKCTL_ASPM_L0S | PCI_EXP_LNKCTL_ASPM_L1);
+		pcie_lnkctl_clear_and_set(pdev, PCI_EXP_LNKCTL_ASPM_L0S |
+						PCI_EXP_LNKCTL_ASPM_L1, 0);
 
 		/*
 		 * Both upstream and downstream PCIe components should
 		 * have the same ASPM settings.
 		 */
-		pcie_capability_clear_word(parent, PCI_EXP_LNKCTL,
-			PCI_EXP_LNKCTL_ASPM_L0S | PCI_EXP_LNKCTL_ASPM_L1);
+		pcie_lnkctl_clear_and_set(parent,
+					  PCI_EXP_LNKCTL_ASPM_L0S |
+					  PCI_EXP_LNKCTL_ASPM_L1, 0);
 
 		ath_info(common, "Disabling ASPM since BTCOEX is enabled\n");
 		return;