Commit 50e9c852 authored by Viresh Kumar's avatar Viresh Kumar Committed by Rafael J. Wysocki
Browse files

cpufreq: Add doc style comment about cpufreq_cpu_{get|put}() 



This clearly states what the code inside these routines is doing and how these
must be used.

Signed-off-by: default avatarViresh Kumar <viresh.kumar@linaro.org>
Acked-by: default avatarSaravana Kannan <skannan@codeaurora.org>
Signed-off-by: default avatarRafael J. Wysocki <rafael.j.wysocki@intel.com>
parent f133d08a

drivers/cpufreq/cpufreq.c

+27 −0
Original line number Diff line number Diff line
@@ -207,6 +207,23 @@ struct cpufreq_policy *cpufreq_cpu_get_raw(unsigned int cpu) 
	return per_cpu(cpufreq_cpu_data, cpu);

}



/**

 * cpufreq_cpu_get: returns policy for a cpu and marks it busy.

 *

 * @cpu: cpu to find policy for.

 *

 * This returns policy for 'cpu', returns NULL if it doesn't exist.

 * It also increments the kobject reference count to mark it busy and so would

 * require a corresponding call to cpufreq_cpu_put() to decrement it back.

 * If corresponding call cpufreq_cpu_put() isn't made, the policy wouldn't be

 * freed as that depends on the kobj count.

 *

 * It also takes a read-lock of 'cpufreq_rwsem' and doesn't put it back if a

 * valid policy is found. This is done to make sure the driver doesn't get

 * unregistered while the policy is being used.

 *

 * Return: A valid policy on success, otherwise NULL on failure.

 */

struct cpufreq_policy *cpufreq_cpu_get(unsigned int cpu)

{

	struct cpufreq_policy *policy = NULL;
@@ -237,6 +254,16 @@ struct cpufreq_policy *cpufreq_cpu_get(unsigned int cpu) 
}

EXPORT_SYMBOL_GPL(cpufreq_cpu_get);



/**

 * cpufreq_cpu_put: Decrements the usage count of a policy

 *

 * @policy: policy earlier returned by cpufreq_cpu_get().

 *

 * This decrements the kobject reference count incremented earlier by calling

 * cpufreq_cpu_get().

 *

 * It also drops the read-lock of 'cpufreq_rwsem' taken at cpufreq_cpu_get().

 */

void cpufreq_cpu_put(struct cpufreq_policy *policy)

{

	kobject_put(&policy->kobj);