diff options
| author | Kai-Heng Feng <kai.heng.feng@canonical.com> | 2019-10-18 15:38:47 +0800 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2020-01-09 10:19:52 +0100 |
| commit | eef2e98832a1cbea9a66b46b5a42d38fc96bccf2 (patch) | |
| tree | 6982c81e84b109670631b21555478667514195d5 /drivers | |
| parent | f1f7ec8e5b5408b8723f2f29847dcc3488a4246c (diff) | |
PCI: Add a helper to check Power Resource Requirements _PR3 existence
[ Upstream commit 52525b7a3cf82adec5c6cf0ecbd23ff228badc94 ]
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>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/pci/pci.c | 18 |
1 files changed, 18 insertions, 0 deletions
diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index a97e2571a527..fcfaadc774ee 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -5854,6 +5854,24 @@ 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 |