diff options
| -rw-r--r-- | drivers/cpufreq/cpufreq.c | 66 |
1 files changed, 26 insertions, 40 deletions
diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c index 0f17ad8..b03771d 100644 --- a/drivers/cpufreq/cpufreq.c +++ b/drivers/cpufreq/cpufreq.c @@ -28,6 +28,7 @@ #include <linux/cpu.h> #include <linux/completion.h> #include <linux/mutex.h> +#include <linux/syscore_ops.h> #include <trace/events/power.h> @@ -1340,35 +1341,31 @@ out: } EXPORT_SYMBOL(cpufreq_get); +static struct sysdev_driver cpufreq_sysdev_driver = { + .add = cpufreq_add_dev, + .remove = cpufreq_remove_dev, +}; + /** - * cpufreq_suspend - let the low level driver prepare for suspend + * cpufreq_bp_suspend - Prepare the boot CPU for system suspend. + * + * This function is only executed for the boot processor. The other CPUs + * have been put offline by means of CPU hotplug. */ - -static int cpufreq_suspend(struct sys_device *sysdev, pm_message_t pmsg) +static int cpufreq_bp_suspend(void) { int ret = 0; - int cpu = sysdev->id; + int cpu = smp_processor_id(); struct cpufreq_policy *cpu_policy; dprintk("suspending cpu %u\n", cpu); - if (!cpu_online(cpu)) - return 0; - - /* we may be lax here as interrupts are off. Nonetheless - * we need to grab the correct cpu policy, as to check - * whether we really run on this CPU. - */ - + /* If there's no policy for the boot CPU, we have nothing to do. */ cpu_policy = cpufreq_cpu_get(cpu); if (!cpu_policy) - return -EINVAL; - - /* only handle each CPU group once */ - if (unlikely(cpu_policy->cpu != cpu)) - goto out; + return 0; if (cpufreq_driver->suspend) { ret = cpufreq_driver->suspend(cpu_policy); @@ -1377,13 +1374,12 @@ static int cpufreq_suspend(struct sys_device *sysdev, pm_message_t pmsg) "step on CPU %u\n", cpu_policy->cpu); } -out: cpufreq_cpu_put(cpu_policy); return ret; } /** - * cpufreq_resume - restore proper CPU frequency handling after resume + * cpufreq_bp_resume - Restore proper frequency handling of the boot CPU. * * 1.) resume CPUfreq hardware support (cpufreq_driver->resume()) * 2.) schedule call cpufreq_update_policy() ASAP as interrupts are @@ -1391,31 +1387,23 @@ out: * what we believe it to be. This is a bit later than when it * should be, but nonethteless it's better than calling * cpufreq_driver->get() here which might re-enable interrupts... + * + * This function is only executed for the boot CPU. The other CPUs have not + * been turned on yet. */ -static int cpufreq_resume(struct sys_device *sysdev) +static void cpufreq_bp_resume(void) { int ret = 0; - int cpu = sysdev->id; + int cpu = smp_processor_id(); struct cpufreq_policy *cpu_policy; dprintk("resuming cpu %u\n", cpu); - if (!cpu_online(cpu)) - return 0; - - /* we may be lax here as interrupts are off. Nonetheless - * we need to grab the correct cpu policy, as to check - * whether we really run on this CPU. - */ - + /* If there's no policy for the boot CPU, we have nothing to do. */ cpu_policy = cpufreq_cpu_get(cpu); if (!cpu_policy) - return -EINVAL; - - /* only handle each CPU group once */ - if (unlikely(cpu_policy->cpu != cpu)) - goto fail; + return; if (cpufreq_driver->resume) { ret = cpufreq_driver->resume(cpu_policy); @@ -1430,14 +1418,11 @@ static int cpufreq_resume(struct sys_device *sysdev) fail: cpufreq_cpu_put(cpu_policy); - return ret; } -static struct sysdev_driver cpufreq_sysdev_driver = { - .add = cpufreq_add_dev, - .remove = cpufreq_remove_dev, - .suspend = cpufreq_suspend, - .resume = cpufreq_resume, +static struct syscore_ops cpufreq_syscore_ops = { + .suspend = cpufreq_bp_suspend, + .resume = cpufreq_bp_resume, }; @@ -2002,6 +1987,7 @@ static int __init cpufreq_core_init(void) cpufreq_global_kobject = kobject_create_and_add("cpufreq", &cpu_sysdev_class.kset.kobj); BUG_ON(!cpufreq_global_kobject); + register_syscore_ops(&cpufreq_syscore_ops); return 0; } |