From: =?UTF-8?q?Ilpo=20J=C3=A4rvinen?= <ilpo.jarvinen@linux.intel.com>
Date: Mon, 17 Jul 2023 15:04:55 +0300
Subject: PCI: pciehp: Use RMW accessors for changing LNKCTL
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Git-commit: 5f75f96c61039151c193775d776fde42477eace1
Patch-mainline: 6.6-rc1
References: git-fixes
As hotplug is not the only driver touching LNKCTL, use the RMW capability
accessor which handles concurrent changes correctly.
Suggested-by: Lukas Wunner <lukas@wunner.de>
Fixes: 7f822999e12a ("PCI: pciehp: Add Disable/enable link functions")
Link: https://lore.kernel.org/r/20230717120503.15276-4-ilpo.jarvinen@linux.intel.com
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: "Rafael J. Wysocki" <rafael@kernel.org>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
---
drivers/pci/hotplug/pciehp_hpc.c | 12 +++---------
1 file changed, 3 insertions(+), 9 deletions(-)
--- a/drivers/pci/hotplug/pciehp_hpc.c
+++ b/drivers/pci/hotplug/pciehp_hpc.c
@@ -312,17 +312,11 @@ int pciehp_check_link_status(struct cont
static int __pciehp_link_set(struct controller *ctrl, bool enable)
{
struct pci_dev *pdev = ctrl_dev(ctrl);
- u16 lnk_ctrl;
- pcie_capability_read_word(pdev, PCI_EXP_LNKCTL, &lnk_ctrl);
+ pcie_capability_clear_and_set_word(pdev, PCI_EXP_LNKCTL,
+ PCI_EXP_LNKCTL_LD,
+ enable ? 0 : PCI_EXP_LNKCTL_LD);
- if (enable)
- lnk_ctrl &= ~PCI_EXP_LNKCTL_LD;
- else
- lnk_ctrl |= PCI_EXP_LNKCTL_LD;
-
- pcie_capability_write_word(pdev, PCI_EXP_LNKCTL, lnk_ctrl);
- ctrl_dbg(ctrl, "%s: lnk_ctrl = %x\n", __func__, lnk_ctrl);
return 0;
}