Commit accd2dd7 authored by Rafael J. Wysocki's avatar Rafael J. Wysocki
Browse files

PCI/ASPM: Add pcie_aspm_enabled() 



Add a function checking whether or not PCIe ASPM has been enabled for
a given device.

It will be used by the NVMe driver to decide how to handle the
device during system suspend.

Signed-off-by: default avatarRafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: default avatarKeith Busch <keith.busch@intel.com>
Acked-by: default avatarBjorn Helgaas <bhelgaas@google.com>
parent d45331b0

drivers/pci/pcie/aspm.c

+20 −0
Original line number Diff line number Diff line
@@ -1170,6 +1170,26 @@ static int pcie_aspm_get_policy(char *buffer, const struct kernel_param *kp) 
module_param_call(policy, pcie_aspm_set_policy, pcie_aspm_get_policy,

	NULL, 0644);



/**

 * pcie_aspm_enabled - Check if PCIe ASPM has been enabled for a device.

 * @pdev: Target device.

 */

bool pcie_aspm_enabled(struct pci_dev *pdev)

{

	struct pci_dev *bridge = pci_upstream_bridge(pdev);

	bool ret;



	if (!bridge)

		return false;



	mutex_lock(&aspm_lock);

	ret = bridge->link_state ? !!bridge->link_state->aspm_enabled : false;

	mutex_unlock(&aspm_lock);



	return ret;

}

EXPORT_SYMBOL_GPL(pcie_aspm_enabled);



#ifdef CONFIG_PCIEASPM_DEBUG

static ssize_t link_state_show(struct device *dev,

		struct device_attribute *attr,

include/linux/pci.h

+2 −0
Original line number Diff line number Diff line
@@ -1567,8 +1567,10 @@ extern bool pcie_ports_native; 


#ifdef CONFIG_PCIEASPM

bool pcie_aspm_support_enabled(void);

bool pcie_aspm_enabled(struct pci_dev *pdev);

#else

static inline bool pcie_aspm_support_enabled(void) { return false; }

static inline bool pcie_aspm_enabled(struct pci_dev *pdev) { return false; }

#endif



#ifdef CONFIG_PCIEAER

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