[PATCH 1/2] PCI: Avoid runtime resuming devices if system is shutting down

Mario Limonciello
2023-12-13T18:27:27Z

When the system is going to S5 resuming devices is unnecessary at
best and may cause problems for power consumption at S5 at worst.

Check the target `system_state` in the pci driver shutdown() callback
and skip the runtime resume step if the system is being powered off.

Cc: mpearson-lenovo@squebb.ca
Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
---
drivers/pci/pci-driver.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/pci/pci-driver.c b/drivers/pci/pci-driver.c
index 51ec9e7e784f..5a6f7a786952 100644
--- a/drivers/pci/pci-driver.c
+++ b/drivers/pci/pci-driver.c
@@ -507,7 +507,9 @@ static void pci_device_shutdown(struct device *dev)
struct pci_dev *pci_dev = to_pci_dev(dev);
struct pci_driver *drv = pci_dev->driver;

- pm_runtime_resume(dev);
+ /* If system will go to S5, don't wake up PCI devices for shutdown */
+ if (system_state != SYSTEM_POWER_OFF)
+ pm_runtime_resume(dev);

if (drv && drv->shutdown)
drv->shutdown(pci_dev);
--
2.34.1