include/linux/pm_qos.h

   1 #ifndef _LINUX_PM_QOS_H
   2 #define _LINUX_PM_QOS_H
   3 /* interface for the pm_qos_power infrastructure of the linux kernel.
   4  *
   5  * Mark Gross <mgross@linux.intel.com>
   6  */
   7 #include <linux/plist.h>
   8 #include <linux/notifier.h>
   9 #include <linux/miscdevice.h>
  10 #include <linux/device.h>
  11
  12 enum {
  13         PM_QOS_RESERVED = 0,
  14         PM_QOS_CPU_DMA_LATENCY,
  15         PM_QOS_NETWORK_LATENCY,
  16         PM_QOS_NETWORK_THROUGHPUT,
  17
  18         /* insert new class ID */
  19         PM_QOS_NUM_CLASSES,
  20 };
  21
  22 #define PM_QOS_DEFAULT_VALUE -1
  23
  24 #define PM_QOS_CPU_DMA_LAT_DEFAULT_VALUE        (2000 * USEC_PER_SEC)
  25 #define PM_QOS_NETWORK_LAT_DEFAULT_VALUE        (2000 * USEC_PER_SEC)
  26 #define PM_QOS_NETWORK_THROUGHPUT_DEFAULT_VALUE 0
  27 #define PM_QOS_DEV_LAT_DEFAULT_VALUE            0
  28
  29 struct pm_qos_request {
  30         struct plist_node node;
  31         int pm_qos_class;
  32 };
  33
  34 struct dev_pm_qos_request {
  35         struct plist_node node;
  36         struct device *dev;
  37 };
  38
  39 enum pm_qos_type {
  40         PM_QOS_UNITIALIZED,
  41         PM_QOS_MAX,             /* return the largest value */
  42         PM_QOS_MIN              /* return the smallest value */
  43 };
  44
  45 /*
  46  * Note: The lockless read path depends on the CPU accessing
  47  * target_value atomically.  Atomic access is only guaranteed on all CPU
  48  * types linux supports for 32 bit quantites
  49  */
  50 struct pm_qos_constraints {
  51         struct plist_head list;
  52         s32 target_value;       /* Do not change to 64 bit */
  53         s32 default_value;
  54         enum pm_qos_type type;
  55         struct blocking_notifier_head *notifiers;
  56 };
  57
  58 /* Action requested to pm_qos_update_target */
  59 enum pm_qos_req_action {
  60         PM_QOS_ADD_REQ,         /* Add a new request */
  61         PM_QOS_UPDATE_REQ,      /* Update an existing request */
  62         PM_QOS_REMOVE_REQ       /* Remove an existing request */
  63 };
  64
  65 static inline int dev_pm_qos_request_active(struct dev_pm_qos_request *req)
  66 {
  67         return req->dev != 0;
  68 }
  69
  70 int pm_qos_update_target(struct pm_qos_constraints *c, struct plist_node *node,
  71                          enum pm_qos_req_action action, int value);
  72 void pm_qos_add_request(struct pm_qos_request *req, int pm_qos_class,
  73                         s32 value);
  74 void pm_qos_update_request(struct pm_qos_request *req,
  75                            s32 new_value);
  76 void pm_qos_remove_request(struct pm_qos_request *req);
  77
  78 int pm_qos_request(int pm_qos_class);
  79 int pm_qos_add_notifier(int pm_qos_class, struct notifier_block *notifier);
  80 int pm_qos_remove_notifier(int pm_qos_class, struct notifier_block *notifier);
  81 int pm_qos_request_active(struct pm_qos_request *req);
  82 s32 pm_qos_read_value(struct pm_qos_constraints *c);
  83
  84 #ifdef CONFIG_PM
  85 s32 __dev_pm_qos_read_value(struct device *dev);
  86 s32 dev_pm_qos_read_value(struct device *dev);
  87 int dev_pm_qos_add_request(struct device *dev, struct dev_pm_qos_request *req,
  88                            s32 value);
  89 int dev_pm_qos_update_request(struct dev_pm_qos_request *req, s32 new_value);
  90 int dev_pm_qos_remove_request(struct dev_pm_qos_request *req);
  91 int dev_pm_qos_add_notifier(struct device *dev,
  92                             struct notifier_block *notifier);
  93 int dev_pm_qos_remove_notifier(struct device *dev,
  94                                struct notifier_block *notifier);
  95 int dev_pm_qos_add_global_notifier(struct notifier_block *notifier);
  96 int dev_pm_qos_remove_global_notifier(struct notifier_block *notifier);
  97 void dev_pm_qos_constraints_init(struct device *dev);
  98 void dev_pm_qos_constraints_destroy(struct device *dev);
  99 int dev_pm_qos_add_ancestor_request(struct device *dev,
 100                                     struct dev_pm_qos_request *req, s32 value);
 101 #else
 102 static inline s32 __dev_pm_qos_read_value(struct device *dev)
 103                         { return 0; }
 104 static inline s32 dev_pm_qos_read_value(struct device *dev)
 105                         { return 0; }
 106 static inline int dev_pm_qos_add_request(struct device *dev,
 107                                          struct dev_pm_qos_request *req,
 108                                          s32 value)
 109                         { return 0; }
 110 static inline int dev_pm_qos_update_request(struct dev_pm_qos_request *req,
 111                                             s32 new_value)
 112                         { return 0; }
 113 static inline int dev_pm_qos_remove_request(struct dev_pm_qos_request *req)
 114                         { return 0; }
 115 static inline int dev_pm_qos_add_notifier(struct device *dev,
 116                                           struct notifier_block *notifier)
 117                         { return 0; }
 118 static inline int dev_pm_qos_remove_notifier(struct device *dev,
 119                                              struct notifier_block *notifier)
 120                         { return 0; }
 121 static inline int dev_pm_qos_add_global_notifier(
 122                                         struct notifier_block *notifier)
 123                         { return 0; }
 124 static inline int dev_pm_qos_remove_global_notifier(
 125                                         struct notifier_block *notifier)
 126                         { return 0; }
 127 static inline void dev_pm_qos_constraints_init(struct device *dev)
 128 {
 129         dev->power.power_state = PMSG_ON;
 130 }
 131 static inline void dev_pm_qos_constraints_destroy(struct device *dev)
 132 {
 133         dev->power.power_state = PMSG_INVALID;
 134 }
 135 static inline int dev_pm_qos_add_ancestor_request(struct device *dev,
 136                                     struct dev_pm_qos_request *req, s32 value)
 137                         { return 0; }
 138 #endif
 139
 140 #ifdef CONFIG_PM_RUNTIME
 141 int dev_pm_qos_expose_latency_limit(struct device *dev, s32 value);
 142 void dev_pm_qos_hide_latency_limit(struct device *dev);
 143 #else
 144 static inline int dev_pm_qos_expose_latency_limit(struct device *dev, s32 value)
 145                         { return 0; }
 146 static inline void dev_pm_qos_hide_latency_limit(struct device *dev) {}
 147 #endif
 148
 149 #endif