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Originally, this approach was chosen for simplicity when the > driver was first implemented. > > With the introduction of the lightweight faux device interface, we now > have a more appropriate alternative. Migrate the driver to utilize the > faux bus, given that the platform device it previously created was not > a real one anyway. This will simplify the code, reducing its footprint > while maintaining functionality. > > Cc: Lorenzo Pieralisi > Cc: "Rafael J. Wysocki" > Cc: Daniel Lezcano > Cc: linux-pm@vger.kernel.org > Signed-off-by: Sudeep Holla > --- > drivers/cpuidle/cpuidle-psci.c | 32 ++++---------------------------- > 1 file changed, 4 insertions(+), 28 deletions(-) > > diff --git a/drivers/cpuidle/cpuidle-psci.c b/drivers/cpuidle/cpuidle-psci.c > index 2562dc001fc1de69732ef28f383d2809262a3d96..5d4d6daed36d8540ba2ce3dc54a3180731b03d22 100644 > --- a/drivers/cpuidle/cpuidle-psci.c > +++ b/drivers/cpuidle/cpuidle-psci.c > @@ -16,7 +16,7 @@ > #include > #include > #include > -#include > +#include > #include > #include > #include > @@ -404,14 +404,14 @@ static int psci_idle_init_cpu(struct device *dev, int cpu) > * to register cpuidle driver then rollback to cancel all CPUs > * registration. > */ > -static int psci_cpuidle_probe(struct platform_device *pdev) > +static int psci_cpuidle_probe(struct faux_device *fdev) > { > int cpu, ret; > struct cpuidle_driver *drv; > struct cpuidle_device *dev; > > for_each_possible_cpu(cpu) { > - ret = psci_idle_init_cpu(&pdev->dev, cpu); > + ret = psci_idle_init_cpu(&fdev->dev, cpu); > if (ret) > goto out_fail; > } > @@ -431,28 +431,4 @@ static int psci_cpuidle_probe(struct platform_device *pdev) > return ret; > } > > -static struct platform_driver psci_cpuidle_driver = { > - .probe = psci_cpuidle_probe, > - .driver = { > - .name = "psci-cpuidle", > - }, > -}; > - > -static int __init psci_idle_init(void) > -{ > - struct platform_device *pdev; > - int ret; > - > - ret = platform_driver_register(&psci_cpuidle_driver); > - if (ret) > - return ret; > - > - pdev = platform_device_register_simple("psci-cpuidle", -1, NULL, 0); > - if (IS_ERR(pdev)) { > - platform_driver_unregister(&psci_cpuidle_driver); > - return PTR_ERR(pdev); > - } > - > - return 0; > -} > -device_initcall(psci_idle_init); > +module_faux_driver(psci_cpuidle, psci_cpuidle_probe, NULL, true); > I have noticed the following error messages on some of our Tegra devices ... ERR KERN faux psci-cpuidle: probe did not succeed, tearing down the device ERR KERN CPUidle PSCI: Failed to create psci-cpuidle device I had a quick look at this and this occurs because of the following code in the probe cpuidle-psci driver ... /* * If no DT idle states are detected (ret == 0) let the driver * initialization fail accordingly since there is no reason to * initialize the idle driver if only wfi is supported, the * default archictectural back-end already executes wfi * on idle entry. */ ret = dt_init_idle_driver(drv, psci_idle_state_match, 1); if (ret <= 0) return ret ? : -ENODEV; So although it could be argued that the error message is valid, I am not sure if there is anything that mandates that we need to have the idle-states present. We are always checking for new kernel errors and so if something new occurs, I am trying to figure out what is the correct way to fix. For this case I am not sure what is best. Thanks Jon -- nvpublic