PCI/ASPM: Add pcie_aspm_get_link()

Factor out getting the link associated with a pci_dev and use this helper
where appropriate.  In addition this helper will be used in a subsequent
patch of this series.

Link: https://lore.kernel.org/r/19d33770-29de-a9af-4d85-f2b30269d383@gmail.com
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
This commit is contained in:
Heiner Kallweit 2019-10-05 14:07:18 +02:00 committed by Bjorn Helgaas
parent 35efea32b2
commit 687aaf386a

View file

@ -1066,19 +1066,26 @@ void pcie_aspm_powersave_config_link(struct pci_dev *pdev)
up_read(&pci_bus_sem);
}
static int __pci_disable_link_state(struct pci_dev *pdev, int state, bool sem)
static struct pcie_link_state *pcie_aspm_get_link(struct pci_dev *pdev)
{
struct pci_dev *parent = pdev->bus->self;
struct pcie_link_state *link;
struct pci_dev *bridge;
if (!pci_is_pcie(pdev))
return 0;
return NULL;
if (pcie_downstream_port(pdev))
parent = pdev;
if (!parent || !parent->link_state)
bridge = pci_upstream_bridge(pdev);
if (!bridge || !pci_is_pcie(bridge))
return NULL;
return bridge->link_state;
}
static int __pci_disable_link_state(struct pci_dev *pdev, int state, bool sem)
{
struct pcie_link_state *link = pcie_aspm_get_link(pdev);
if (!link)
return -EINVAL;
/*
* A driver requested that ASPM be disabled on this device, but
* if we don't have permission to manage ASPM (e.g., on ACPI
@ -1095,7 +1102,6 @@ static int __pci_disable_link_state(struct pci_dev *pdev, int state, bool sem)
if (sem)
down_read(&pci_bus_sem);
mutex_lock(&aspm_lock);
link = parent->link_state;
if (state & PCIE_LINK_STATE_L0S)
link->aspm_disable |= ASPM_STATE_L0S;
if (state & PCIE_LINK_STATE_L1)
@ -1193,12 +1199,12 @@ module_param_call(policy, pcie_aspm_set_policy, pcie_aspm_get_policy,
*/
bool pcie_aspm_enabled(struct pci_dev *pdev)
{
struct pci_dev *bridge = pci_upstream_bridge(pdev);
struct pcie_link_state *link = pcie_aspm_get_link(pdev);
if (!bridge)
if (!link)
return false;
return bridge->link_state ? !!bridge->link_state->aspm_enabled : false;
return link->aspm_enabled;
}
EXPORT_SYMBOL_GPL(pcie_aspm_enabled);