On Tue, Mar 24, 2015 at 11:37:03PM +0800, Aaron Lu wrote: > On 03/24/2015 10:08 PM, Bjorn Helgaas wrote: > > On Tue, Mar 24, 2015 at 05:04:58PM +0800, Aaron Lu wrote: > >> @@ -575,6 +637,9 @@ static void pci_acpi_setup(struct device *dev) > >> if (!adev) > >> return; > >> > >> + if (pci_dev->pm_cap) > >> + pci_acpi_delay_optimize(pci_dev, adev->handle); > > > > Is the "pm_cap" test really necessary? If we do it this way, we then have > > to convince ourselves that pdev->d3cold_delay and pdev->d3_delay are only > > needed when pdev has a pm_cap. > > > > If we *always* fill in the delay values, it's possible they won't be used, > > but we don't have to prove any connection between them and a pm_cap, so > > the code is easier to analyze. > > I remembered why I did the pm_cap test: the d3cold_delay and d3_delay is > only filled when pm_cap is set in pci_pm_init - if the device doesn't > have PCI_CAP_ID_PM set, its pm_cap will be 0 and d3cold_delay, d3_delay > will not be assigned. Yes, that's true, so I can see why you'd test pm_cap here, too. But I don't think it's necessary to propagate that connection here, so I'd omit the test. Bjorn -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
