Commit af5376a7 authored by Sudeep Holla's avatar Sudeep Holla Committed by Rafael J. Wysocki
Browse files

cpuidle: psci: Transition to the faux device interface 



The PSCI cpuidle driver does not require the creation of a platform
device. 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.

Signed-off-by: default avatarSudeep Holla <sudeep.holla@arm.com>
Link: https://patch.msgid.link/20250317-plat2faux_dev-v1-1-5fe67c085ad5@arm.com


Signed-off-by: default avatarRafael J. Wysocki <rafael.j.wysocki@intel.com>
parent d4a7882f

drivers/cpuidle/cpuidle-psci.c

+9 −17
Original line number Diff line number Diff line
@@ -16,7 +16,7 @@ 
#include <linux/kernel.h>

#include <linux/module.h>

#include <linux/of.h>

#include <linux/platform_device.h>

#include <linux/device/faux.h>

#include <linux/psci.h>

#include <linux/pm_domain.h>

#include <linux/pm_runtime.h>
@@ -407,14 +407,14 @@ 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_present_cpu(cpu) {

		ret = psci_idle_init_cpu(&pdev->dev, cpu);

		ret = psci_idle_init_cpu(&fdev->dev, cpu);

		if (ret)

			goto out_fail;

	}
@@ -434,26 +434,18 @@ static int psci_cpuidle_probe(struct platform_device *pdev) 
	return ret;

}



static struct platform_driver psci_cpuidle_driver = {

static struct faux_device_ops psci_cpuidle_ops = {

	.probe = psci_cpuidle_probe,

	.driver = {

		.name = "psci-cpuidle",

	},

};



static int __init psci_idle_init(void)

{

	struct platform_device *pdev;

	int ret;

	struct faux_device *fdev;



	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);

	fdev = faux_device_create("psci-cpuidle", NULL, &psci_cpuidle_ops);

	if (!fdev) {

		pr_err("Failed to create psci-cpuidle device\n");

		return -ENODEV;

	}



	return 0;