linux-stable/include/linux/opp.h

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PM: Introduce library for device-specific OPPs (v7) SoCs have a standard set of tuples consisting of frequency and voltage pairs that the device will support per voltage domain. These are called Operating Performance Points or OPPs. The actual definitions of OPP varies over silicon versions. For a specific domain, we can have a set of {frequency, voltage} pairs. As the kernel boots and more information is available, a default set of these are activated based on the precise nature of device. Further on operation, based on conditions prevailing in the system (such as temperature), some OPP availability may be temporarily controlled by the SoC frameworks. To implement an OPP, some sort of power management support is necessary hence this library depends on CONFIG_PM. Contributions include: Sanjeev Premi for the initial concept: http://patchwork.kernel.org/patch/50998/ Kevin Hilman for converting original design to device-based. Kevin Hilman and Paul Walmsey for cleaning up many of the function abstractions, improvements and data structure handling. Romit Dasgupta for using enums instead of opp pointers. Thara Gopinath, Eduardo Valentin and Vishwanath BS for fixes and cleanups. Linus Walleij for recommending this layer be made generic for usage in other architectures beyond OMAP and ARM. Mark Brown, Andrew Morton, Rafael J. Wysocki, Paul E. McKenney for valuable improvements. Discussions and comments from: http://marc.info/?l=linux-omap&m=126033945313269&w=2 http://marc.info/?l=linux-omap&m=125482970102327&w=2 http://marc.info/?t=125809247500002&r=1&w=2 http://marc.info/?l=linux-omap&m=126025973426007&w=2 http://marc.info/?t=128152609200064&r=1&w=2 http://marc.info/?t=128468723000002&r=1&w=2 incorporated. v1: http://marc.info/?t=128468723000002&r=1&w=2 Signed-off-by: Nishanth Menon <nm@ti.com> Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2010-10-12 22:13:10 +00:00
/*
* Generic OPP Interface
*
* Copyright (C) 2009-2010 Texas Instruments Incorporated.
* Nishanth Menon
* Romit Dasgupta
* Kevin Hilman
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#ifndef __LINUX_OPP_H__
#define __LINUX_OPP_H__
#include <linux/err.h>
#include <linux/cpufreq.h>
struct opp;
#if defined(CONFIG_PM_OPP)
unsigned long opp_get_voltage(struct opp *opp);
unsigned long opp_get_freq(struct opp *opp);
int opp_get_opp_count(struct device *dev);
struct opp *opp_find_freq_exact(struct device *dev, unsigned long freq,
bool available);
struct opp *opp_find_freq_floor(struct device *dev, unsigned long *freq);
struct opp *opp_find_freq_ceil(struct device *dev, unsigned long *freq);
int opp_add(struct device *dev, unsigned long freq, unsigned long u_volt);
int opp_enable(struct device *dev, unsigned long freq);
int opp_disable(struct device *dev, unsigned long freq);
#else
static inline unsigned long opp_get_voltage(struct opp *opp)
{
return 0;
}
static inline unsigned long opp_get_freq(struct opp *opp)
{
return 0;
}
static inline int opp_get_opp_count(struct device *dev)
{
return 0;
}
static inline struct opp *opp_find_freq_exact(struct device *dev,
unsigned long freq, bool available)
{
return ERR_PTR(-EINVAL);
}
static inline struct opp *opp_find_freq_floor(struct device *dev,
unsigned long *freq)
{
return ERR_PTR(-EINVAL);
}
static inline struct opp *opp_find_freq_ceil(struct device *dev,
unsigned long *freq)
{
return ERR_PTR(-EINVAL);
}
static inline int opp_add(struct device *dev, unsigned long freq,
unsigned long u_volt)
{
return -EINVAL;
}
static inline int opp_enable(struct device *dev, unsigned long freq)
{
return 0;
}
static inline int opp_disable(struct device *dev, unsigned long freq)
{
return 0;
}
#endif /* CONFIG_PM */
#if defined(CONFIG_CPU_FREQ) && defined(CONFIG_PM_OPP)
int opp_init_cpufreq_table(struct device *dev,
struct cpufreq_frequency_table **table);
#else
static inline int opp_init_cpufreq_table(struct device *dev,
struct cpufreq_frequency_table **table)
{
return -EINVAL;
}
#endif /* CONFIG_CPU_FREQ */
#endif /* __LINUX_OPP_H__ */