According to "PCIe r6.0, sec 5.5.4", add note about D0 requirement in pci_enable_link_state() kernel-doc. Signed-off-by: Jian-Hong Pan <jhp@xxxxxxxxxxxxx> Acked-by: Bjorn Helgaas <bhelgaas@xxxxxxxxxx> Reviewed-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@xxxxxxxxxxxxxxx> --- v3: - Fix as readable comments v4: - The same v5: - Tweak and simplify the commit message drivers/pci/pcie/aspm.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/drivers/pci/pcie/aspm.c b/drivers/pci/pcie/aspm.c index 2428d278e015..91a8b35b1ae2 100644 --- a/drivers/pci/pcie/aspm.c +++ b/drivers/pci/pcie/aspm.c @@ -1446,6 +1446,9 @@ static int __pci_enable_link_state(struct pci_dev *pdev, int state, bool locked) * touch the LNKCTL register. Also note that this does not enable states * disabled by pci_disable_link_state(). Return 0 or a negative errno. * + * Note: Ensure devices are in D0 before enabling PCI-PM L1 PM Substates, per + * PCIe r6.0, sec 5.5.4. + * * @pdev: PCI device * @state: Mask of ASPM link states to enable */ @@ -1462,6 +1465,9 @@ EXPORT_SYMBOL(pci_enable_link_state); * can't touch the LNKCTL register. Also note that this does not enable states * disabled by pci_disable_link_state(). Return 0 or a negative errno. * + * Note: Ensure devices are in D0 before enabling PCI-PM L1 PM Substates, per + * PCIe r6.0, sec 5.5.4. + * * @pdev: PCI device * @state: Mask of ASPM link states to enable * -- 2.44.0
