2
0
mirror of https://github.com/edk2-porting/linux-next.git synced 2024-12-25 21:54:06 +08:00
linux-next/include/linux/pm_qos.h
Rafael J. Wysocki 1a9a91525d PM / QoS: Add function dev_pm_qos_read_value() (v3)
To read the current PM QoS value for a given device we need to
make sure that the device's power.constraints object won't be
removed while we're doing that.  For this reason, put the
operation under dev->power.lock and acquire the lock
around the initialization and removal of power.constraints.

Moreover, since we're using the value of power.constraints to
determine whether or not the object is present, the
power.constraints_state field isn't necessary any more and may be
removed.  However, dev_pm_qos_add_request() needs to check if the
device is being removed from the system before allocating a new
PM QoS constraints object for it, so make it use the
power.power_state field of struct device for this purpose.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2011-10-04 21:54:26 +02:00

156 lines
5.0 KiB
C

#ifndef _LINUX_PM_QOS_H
#define _LINUX_PM_QOS_H
/* interface for the pm_qos_power infrastructure of the linux kernel.
*
* Mark Gross <mgross@linux.intel.com>
*/
#include <linux/plist.h>
#include <linux/notifier.h>
#include <linux/miscdevice.h>
#include <linux/device.h>
#define PM_QOS_RESERVED 0
#define PM_QOS_CPU_DMA_LATENCY 1
#define PM_QOS_NETWORK_LATENCY 2
#define PM_QOS_NETWORK_THROUGHPUT 3
#define PM_QOS_NUM_CLASSES 4
#define PM_QOS_DEFAULT_VALUE -1
#define PM_QOS_CPU_DMA_LAT_DEFAULT_VALUE (2000 * USEC_PER_SEC)
#define PM_QOS_NETWORK_LAT_DEFAULT_VALUE (2000 * USEC_PER_SEC)
#define PM_QOS_NETWORK_THROUGHPUT_DEFAULT_VALUE 0
#define PM_QOS_DEV_LAT_DEFAULT_VALUE 0
struct pm_qos_request {
struct plist_node node;
int pm_qos_class;
};
struct dev_pm_qos_request {
struct plist_node node;
struct device *dev;
};
enum pm_qos_type {
PM_QOS_UNITIALIZED,
PM_QOS_MAX, /* return the largest value */
PM_QOS_MIN /* return the smallest value */
};
/*
* Note: The lockless read path depends on the CPU accessing
* target_value atomically. Atomic access is only guaranteed on all CPU
* types linux supports for 32 bit quantites
*/
struct pm_qos_constraints {
struct plist_head list;
s32 target_value; /* Do not change to 64 bit */
s32 default_value;
enum pm_qos_type type;
struct blocking_notifier_head *notifiers;
};
/* Action requested to pm_qos_update_target */
enum pm_qos_req_action {
PM_QOS_ADD_REQ, /* Add a new request */
PM_QOS_UPDATE_REQ, /* Update an existing request */
PM_QOS_REMOVE_REQ /* Remove an existing request */
};
static inline int dev_pm_qos_request_active(struct dev_pm_qos_request *req)
{
return req->dev != 0;
}
#ifdef CONFIG_PM
int pm_qos_update_target(struct pm_qos_constraints *c, struct plist_node *node,
enum pm_qos_req_action action, int value);
void pm_qos_add_request(struct pm_qos_request *req, int pm_qos_class,
s32 value);
void pm_qos_update_request(struct pm_qos_request *req,
s32 new_value);
void pm_qos_remove_request(struct pm_qos_request *req);
int pm_qos_request(int pm_qos_class);
int pm_qos_add_notifier(int pm_qos_class, struct notifier_block *notifier);
int pm_qos_remove_notifier(int pm_qos_class, struct notifier_block *notifier);
int pm_qos_request_active(struct pm_qos_request *req);
s32 pm_qos_read_value(struct pm_qos_constraints *c);
s32 dev_pm_qos_read_value(struct device *dev);
int dev_pm_qos_add_request(struct device *dev, struct dev_pm_qos_request *req,
s32 value);
int dev_pm_qos_update_request(struct dev_pm_qos_request *req, s32 new_value);
int dev_pm_qos_remove_request(struct dev_pm_qos_request *req);
int dev_pm_qos_add_notifier(struct device *dev,
struct notifier_block *notifier);
int dev_pm_qos_remove_notifier(struct device *dev,
struct notifier_block *notifier);
int dev_pm_qos_add_global_notifier(struct notifier_block *notifier);
int dev_pm_qos_remove_global_notifier(struct notifier_block *notifier);
void dev_pm_qos_constraints_init(struct device *dev);
void dev_pm_qos_constraints_destroy(struct device *dev);
#else
static inline int pm_qos_update_target(struct pm_qos_constraints *c,
struct plist_node *node,
enum pm_qos_req_action action,
int value)
{ return 0; }
static inline void pm_qos_add_request(struct pm_qos_request *req,
int pm_qos_class, s32 value)
{ return; }
static inline void pm_qos_update_request(struct pm_qos_request *req,
s32 new_value)
{ return; }
static inline void pm_qos_remove_request(struct pm_qos_request *req)
{ return; }
static inline int pm_qos_request(int pm_qos_class)
{ return 0; }
static inline int pm_qos_add_notifier(int pm_qos_class,
struct notifier_block *notifier)
{ return 0; }
static inline int pm_qos_remove_notifier(int pm_qos_class,
struct notifier_block *notifier)
{ return 0; }
static inline int pm_qos_request_active(struct pm_qos_request *req)
{ return 0; }
static inline s32 pm_qos_read_value(struct pm_qos_constraints *c)
{ return 0; }
static inline s32 dev_pm_qos_read_value(struct device *dev)
{ return 0; }
static inline int dev_pm_qos_add_request(struct device *dev,
struct dev_pm_qos_request *req,
s32 value)
{ return 0; }
static inline int dev_pm_qos_update_request(struct dev_pm_qos_request *req,
s32 new_value)
{ return 0; }
static inline int dev_pm_qos_remove_request(struct dev_pm_qos_request *req)
{ return 0; }
static inline int dev_pm_qos_add_notifier(struct device *dev,
struct notifier_block *notifier)
{ return 0; }
static inline int dev_pm_qos_remove_notifier(struct device *dev,
struct notifier_block *notifier)
{ return 0; }
static inline int dev_pm_qos_add_global_notifier(
struct notifier_block *notifier)
{ return 0; }
static inline int dev_pm_qos_remove_global_notifier(
struct notifier_block *notifier)
{ return 0; }
static inline void dev_pm_qos_constraints_init(struct device *dev)
{
dev->power.power_state = PMSG_ON;
}
static inline void dev_pm_qos_constraints_destroy(struct device *dev)
{
dev->power.power_state = PMSG_INVALID;
}
#endif
#endif