Commit 27e289dc authored by Stratos Karafotis's avatar Stratos Karafotis Committed by Rafael J. Wysocki
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cpufreq: Introduce macros for cpufreq_frequency_table iteration 



Many cpufreq drivers need to iterate over the cpufreq_frequency_table
for various tasks.

This patch introduces two macros which can be used for iteration over
cpufreq_frequency_table keeping a common coding style across drivers:

- cpufreq_for_each_entry: iterate over each entry of the table
- cpufreq_for_each_valid_entry: iterate over each entry that contains
a valid frequency.

It should have no functional changes.

Signed-off-by: default avatarStratos Karafotis <stratosk@semaphore.gr>
Acked-by: default avatarLad, Prabhakar <prabhakar.csengg@gmail.com>
Acked-by: default avatarViresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: default avatarRafael J. Wysocki <rafael.j.wysocki@intel.com>
parent d1db0eea

Documentation/cpu-freq/cpu-drivers.txt

+19 −0
Original line number Diff line number Diff line
@@ -228,3 +228,22 @@ is the corresponding frequency table helper for the ->target 
stage. Just pass the values to this function, and the unsigned int

index returns the number of the frequency table entry which contains

the frequency the CPU shall be set to.



The following macros can be used as iterators over cpufreq_frequency_table:



cpufreq_for_each_entry(pos, table) - iterates over all entries of frequency

table.



cpufreq-for_each_valid_entry(pos, table) - iterates over all entries,

excluding CPUFREQ_ENTRY_INVALID frequencies.

Use arguments "pos" - a cpufreq_frequency_table * as a loop cursor and

"table" - the cpufreq_frequency_table * you want to iterate over.



For example:



	struct cpufreq_frequency_table *pos, *driver_freq_table;



	cpufreq_for_each_entry(pos, driver_freq_table) {

		/* Do something with pos */

		pos->frequency = ...

	}

drivers/cpufreq/cpufreq.c

+11 −0
Original line number Diff line number Diff line
@@ -237,6 +237,17 @@ void cpufreq_cpu_put(struct cpufreq_policy *policy) 
}

EXPORT_SYMBOL_GPL(cpufreq_cpu_put);



bool cpufreq_next_valid(struct cpufreq_frequency_table **pos)

{

	while ((*pos)->frequency != CPUFREQ_TABLE_END)

		if ((*pos)->frequency != CPUFREQ_ENTRY_INVALID)

			return true;

		else

			(*pos)++;

	return false;

}

EXPORT_SYMBOL_GPL(cpufreq_next_valid);



/*********************************************************************

 *            EXTERNALLY AFFECTING FREQUENCY CHANGES                 *

 *********************************************************************/

include/linux/cpufreq.h

+21 −0
Original line number Diff line number Diff line
@@ -468,6 +468,27 @@ struct cpufreq_frequency_table { 
				    * order */

};



bool cpufreq_next_valid(struct cpufreq_frequency_table **pos);



/*

 * cpufreq_for_each_entry -	iterate over a cpufreq_frequency_table

 * @pos:	the cpufreq_frequency_table * to use as a loop cursor.

 * @table:	the cpufreq_frequency_table * to iterate over.

 */



#define cpufreq_for_each_entry(pos, table)	\

	for (pos = table; pos->frequency != CPUFREQ_TABLE_END; pos++)



/*

 * cpufreq_for_each_valid_entry -     iterate over a cpufreq_frequency_table

 *	excluding CPUFREQ_ENTRY_INVALID frequencies.

 * @pos:        the cpufreq_frequency_table * to use as a loop cursor.

 * @table:      the cpufreq_frequency_table * to iterate over.

 */



#define cpufreq_for_each_valid_entry(pos, table)	\

	for (pos = table; cpufreq_next_valid(&pos); pos++)



int cpufreq_frequency_table_cpuinfo(struct cpufreq_policy *policy,

				    struct cpufreq_frequency_table *table);

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