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authorKai-Heng Feng <kai.heng.feng@canonical.com>2019-10-18 10:38:47 +0300
committerTakashi Iwai <tiwai@suse.de>2019-10-21 16:13:18 +0300
commit52525b7a3cf82adec5c6cf0ecbd23ff228badc94 (patch)
tree673ac3d1e755a12b1a04610066fa15366f56a1e9 /drivers/pci/pci.c
parentacfedcbe1ce4c69e1da914f39c02d945c80198d4 (diff)
downloadlinux-52525b7a3cf82adec5c6cf0ecbd23ff228badc94.tar.xz
PCI: Add a helper to check Power Resource Requirements _PR3 existence
A driver may want to know the existence of _PR3, to choose different runtime suspend behavior. A user will be add in next patch. This is mostly the same as nouveau_pr3_present(). Signed-off-by: Kai-Heng Feng <kai.heng.feng@canonical.com> Acked-by: Bjorn Helgaas <bhelgaas@google.com> Link: https://lore.kernel.org/r/20191018073848.14590-1-kai.heng.feng@canonical.com Signed-off-by: Takashi Iwai <tiwai@suse.de>
Diffstat (limited to 'drivers/pci/pci.c')
-rw-r--r--drivers/pci/pci.c18
1 files changed, 18 insertions, 0 deletions
diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index e7982af9a5d8..1df99d9e350e 100644
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -5856,6 +5856,24 @@ int pci_set_vga_state(struct pci_dev *dev, bool decode,
return 0;
}
+#ifdef CONFIG_ACPI
+bool pci_pr3_present(struct pci_dev *pdev)
+{
+ struct acpi_device *adev;
+
+ if (acpi_disabled)
+ return false;
+
+ adev = ACPI_COMPANION(&pdev->dev);
+ if (!adev)
+ return false;
+
+ return adev->power.flags.power_resources &&
+ acpi_has_method(adev->handle, "_PR3");
+}
+EXPORT_SYMBOL_GPL(pci_pr3_present);
+#endif
+
/**
* pci_add_dma_alias - Add a DMA devfn alias for a device
* @dev: the PCI device for which alias is added