alistair23-linux/drivers/thermal/thermal_core.h
Eduardo Valentin 4e5e4705bf thermal: introduce device tree parser
This patch introduces a device tree bindings for
describing the hardware thermal behavior and limits.
Also a parser to read and interpret the data and feed
it in the thermal framework is presented.

This patch introduces a thermal data parser for device
tree. The parsed data is used to build thermal zones
and thermal binding parameters. The output data
can then be used to deploy thermal policies.

This patch adds also documentation regarding this
API and how to define tree nodes to use
this infrastructure.

Note that, in order to be able to have control
on the sensor registration on the DT thermal zone,
it was required to allow changing the thermal zone
.get_temp callback. For this reason, this patch
also removes the 'const' modifier from the .ops
field of thermal zone devices.

Cc: Zhang Rui <rui.zhang@intel.com>
Cc: linux-pm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Eduardo Valentin <eduardo.valentin@ti.com>
2013-12-04 09:31:34 -04:00

90 lines
3.1 KiB
C

/*
* thermal_core.h
*
* Copyright (C) 2012 Intel Corp
* Author: Durgadoss R <durgadoss.r@intel.com>
*
* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; version 2 of the License.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
*
* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
*/
#ifndef __THERMAL_CORE_H__
#define __THERMAL_CORE_H__
#include <linux/device.h>
#include <linux/thermal.h>
/* Initial state of a cooling device during binding */
#define THERMAL_NO_TARGET -1UL
/*
* This structure is used to describe the behavior of
* a certain cooling device on a certain trip point
* in a certain thermal zone
*/
struct thermal_instance {
int id;
char name[THERMAL_NAME_LENGTH];
struct thermal_zone_device *tz;
struct thermal_cooling_device *cdev;
int trip;
unsigned long upper; /* Highest cooling state for this trip point */
unsigned long lower; /* Lowest cooling state for this trip point */
unsigned long target; /* expected cooling state */
char attr_name[THERMAL_NAME_LENGTH];
struct device_attribute attr;
struct list_head tz_node; /* node in tz->thermal_instances */
struct list_head cdev_node; /* node in cdev->thermal_instances */
};
int thermal_register_governor(struct thermal_governor *);
void thermal_unregister_governor(struct thermal_governor *);
#ifdef CONFIG_THERMAL_GOV_STEP_WISE
int thermal_gov_step_wise_register(void);
void thermal_gov_step_wise_unregister(void);
#else
static inline int thermal_gov_step_wise_register(void) { return 0; }
static inline void thermal_gov_step_wise_unregister(void) {}
#endif /* CONFIG_THERMAL_GOV_STEP_WISE */
#ifdef CONFIG_THERMAL_GOV_FAIR_SHARE
int thermal_gov_fair_share_register(void);
void thermal_gov_fair_share_unregister(void);
#else
static inline int thermal_gov_fair_share_register(void) { return 0; }
static inline void thermal_gov_fair_share_unregister(void) {}
#endif /* CONFIG_THERMAL_GOV_FAIR_SHARE */
#ifdef CONFIG_THERMAL_GOV_USER_SPACE
int thermal_gov_user_space_register(void);
void thermal_gov_user_space_unregister(void);
#else
static inline int thermal_gov_user_space_register(void) { return 0; }
static inline void thermal_gov_user_space_unregister(void) {}
#endif /* CONFIG_THERMAL_GOV_USER_SPACE */
/* device tree support */
#ifdef CONFIG_THERMAL_OF
int of_parse_thermal_zones(void);
void of_thermal_destroy_zones(void);
#else
static inline int of_parse_thermal_zones(void) { return 0; }
static inline void of_thermal_destroy_zones(void) { }
#endif
#endif /* __THERMAL_CORE_H__ */