[cc += Rafael, linux-acpi] On Mon, Apr 21, 2025 at 10:05:59PM +0200, Heiner Kallweit wrote: > If there's no platform support for transition to D3cold, then > pci_set_power_state(dev, D3cold) still returns 0, even though > power state is transitioned to D3hot only. We called > pci_enable_wake(dev, D3cold, wakeup) before, therefore PME for > D3hot may not be enabled. Is this a bug? > > Background: > In __pci_set_power_state we have the following: > > error = pci_set_low_power_state(dev, PCI_D3hot, locked); > if (pci_platform_power_transition(dev, PCI_D3cold)) > return error; > > The acpi_pci_set_power_state() stub returns -ENODEV. > Therefore, if error=0, __pci_set_power_state() will > return 0 if pci_platform_power_transition() fails. pci_prepare_to_sleep() calls pci_target_state() right at the top. If wakeup is supported and enabled, pci_target_state() is supposed to find the deepest power state supporting wakeup. If D3cold doesn't support wakeup, D3hot or a shallower state is returned. Hence I don't quite understand how the scenario you're describing could occur in practice. Are you seeing actual issues and have tracked them down to incorrect handling in pci_prepare_to_sleep()? Thanks, Lukas
