ACPI: processor: idle: Redefine two functions as void

Notice that acpi_processor_power_init() and acpi_processor_power_exit()
don't need to return any values because their callers don't check them
anyway, so redefine those functions as void.

While at it, rearrange the code in acpi_processor_power_init() to
reduce the indentation level, get rid of a redundant local variable
in that function, and rephrase a code comment in it.

No intentional functional impact.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Mario Limonciello (AMD) <superm1@kernel.org>
Tested-by: Borislav Petkov (AMD) <bp@alien8.de>
Link: https://patch.msgid.link/20251223100914.2407069-5-lihuisong@huawei.com
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

Author: rafaeljw

drivers/acpi/processor_idle.c

@@ -1391,55 +1391,52 @@ void acpi_processor_unregister_idle_driver(void)
 	cpuidle_unregister_driver(&acpi_idle_driver);
 }
 
-int acpi_processor_power_init(struct acpi_processor *pr)
+void acpi_processor_power_init(struct acpi_processor *pr)
 {
-	int retval;
 	struct cpuidle_device *dev;
 
 	if (disabled_by_idle_boot_param())
-		return 0;
+		return;
 
 	acpi_processor_cstate_first_run_checks();
 
 	if (!acpi_processor_get_power_info(pr))
 		pr->flags.power_setup_done = 1;
 
-	if (pr->flags.power) {
-		dev = kzalloc(sizeof(*dev), GFP_KERNEL);
-		if (!dev)
-			return -ENOMEM;
-		per_cpu(acpi_cpuidle_device, pr->id) = dev;
+	if (!pr->flags.power)
+		return;
 
-		acpi_processor_setup_cpuidle_dev(pr, dev);
+	dev = kzalloc(sizeof(*dev), GFP_KERNEL);
+	if (!dev)
+		return;
 
-		/* Register per-cpu cpuidle_device. Cpuidle driver
-		 * must already be registered before registering device
-		 */
-		retval = cpuidle_register_device(dev);
-		if (retval) {
+	per_cpu(acpi_cpuidle_device, pr->id) = dev;
 
-			per_cpu(acpi_cpuidle_device, pr->id) = NULL;
-			kfree(dev);
-			return retval;
-		}
+	acpi_processor_setup_cpuidle_dev(pr, dev);
+
+	/*
+	 * Register a cpuidle device for this CPU.  The cpuidle driver using
+	 * this device is expected to be registered.
+	 */
+	if (cpuidle_register_device(dev)) {
+		per_cpu(acpi_cpuidle_device, pr->id) = NULL;
+		kfree(dev);
 	}
-	return 0;
 }
 
-int acpi_processor_power_exit(struct acpi_processor *pr)
+void acpi_processor_power_exit(struct acpi_processor *pr)
 {
 	struct cpuidle_device *dev = per_cpu(acpi_cpuidle_device, pr->id);
 
 	if (disabled_by_idle_boot_param())
-		return 0;
+		return;
 
 	if (pr->flags.power) {
 		cpuidle_unregister_device(dev);
 		kfree(dev);
 	}
 
 	pr->flags.power_setup_done = 0;
-	return 0;
 }
 
 MODULE_IMPORT_NS("ACPI_PROCESSOR_IDLE");

include/acpi/processor.h

@@ -419,8 +419,8 @@ static inline void acpi_processor_throttling_init(void) {}
 /* in processor_idle.c */
 extern struct cpuidle_driver acpi_idle_driver;
 #ifdef CONFIG_ACPI_PROCESSOR_IDLE
-int acpi_processor_power_init(struct acpi_processor *pr);
-int acpi_processor_power_exit(struct acpi_processor *pr);
+void acpi_processor_power_init(struct acpi_processor *pr);
+void acpi_processor_power_exit(struct acpi_processor *pr);
 int acpi_processor_power_state_has_changed(struct acpi_processor *pr);
 int acpi_processor_hotplug(struct acpi_processor *pr);
 void acpi_processor_register_idle_driver(void);