SH: cpuidle: check error code at init

Registering the driver, or the device, can fail, let's check the return code
and return the error code to the PM layer.
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

arch/sh/include/asm/suspend.h

@@ -14,9 +14,9 @@ struct swsusp_arch_regs {
 void sh_mobile_call_standby(unsigned long mode);
 
 #ifdef CONFIG_CPU_IDLE
-void sh_mobile_setup_cpuidle(void);
+int sh_mobile_setup_cpuidle(void);
 #else
-static inline void sh_mobile_setup_cpuidle(void) {}
+static inline int sh_mobile_setup_cpuidle(void) { return 0; }
 #endif
 
 /* notifier chains for pre/post sleep hooks */

arch/sh/kernel/cpu/shmobile/cpuidle.c

@@ -91,14 +91,19 @@ static struct cpuidle_driver cpuidle_driver = {
 	.state_count = 3,
 };
 
-void sh_mobile_setup_cpuidle(void)
+int __init sh_mobile_setup_cpuidle(void)
 {
+	int ret;
+
 	if (sh_mobile_sleep_supported & SUSP_SH_SF)
 		cpuidle_driver.states[1].disabled = false;
 
 	if (sh_mobile_sleep_supported & SUSP_SH_STANDBY)
 		cpuidle_driver.states[2].disabled = false;
 
-	if (!cpuidle_register_driver(&cpuidle_driver))
-		cpuidle_register_device(&cpuidle_dev);
+	ret = cpuidle_register_driver(&cpuidle_driver);
+	if (ret)
+		return ret;
+
+	return cpuidle_register_device(&cpuidle_dev);
 }

arch/sh/kernel/cpu/shmobile/pm.c

@@ -150,8 +150,7 @@ static const struct platform_suspend_ops sh_pm_ops = {
 static int __init sh_pm_init(void)
 {
 	suspend_set_ops(&sh_pm_ops);
-	sh_mobile_setup_cpuidle();
-	return 0;
+	return sh_mobile_setup_cpuidle();
 }
 
 late_initcall(sh_pm_init);