This is a note to let you know that I've just added the patch titled
PCI: Add a helper to check Power Resource Requirements _PR3 existence
to the 5.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
pci-add-a-helper-to-check-power-resource-requirement.patch
and it can be found in the queue-5.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit e6563a36a9ed46a5c9d9ecd7d26beaf65ddcdda6
Author: Kai-Heng Feng <kai.heng.feng@xxxxxxxxxxxxx>
Date: Fri Oct 18 15:38:47 2019 +0800
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@xxxxxxxxxxxxx>
Acked-by: Bjorn Helgaas <bhelgaas@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20191018073848.14590-1-kai.heng.feng@xxxxxxxxxxxxx
Signed-off-by: Takashi Iwai <tiwai@xxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
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
diff --git a/include/linux/pci.h b/include/linux/pci.h
index f9088c89a534..1d15c5d49cdd 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -2310,9 +2310,11 @@ struct irq_domain *pci_host_bridge_acpi_msi_domain(struct pci_bus *bus);
void
pci_msi_register_fwnode_provider(struct fwnode_handle *(*fn)(struct device *));
+bool pci_pr3_present(struct pci_dev *pdev);
#else
static inline struct irq_domain *
pci_host_bridge_acpi_msi_domain(struct pci_bus *bus) { return NULL; }
+static bool pci_pr3_present(struct pci_dev *pdev) { return false; }
#endif
#ifdef CONFIG_EEH
