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 #include <linux/workqueue.h>
  12
  13 enum {
  14         PM_QOS_RESERVED = 0,
  15         PM_QOS_CPU_DMA_LATENCY,
  16         PM_QOS_NETWORK_LATENCY,
  17         PM_QOS_NETWORK_THROUGHPUT,
  18
  19         /* insert new class ID */
  20         PM_QOS_NUM_CLASSES,
  21 };
  22
  23 #define PM_QOS_DEFAULT_VALUE -1
  24
  25 #define PM_QOS_CPU_DMA_LAT_DEFAULT_VALUE        (2000 * USEC_PER_SEC)
  26 #define PM_QOS_NETWORK_LAT_DEFAULT_VALUE        (2000 * USEC_PER_SEC)
  27 #define PM_QOS_NETWORK_THROUGHPUT_DEFAULT_VALUE 0
  28 #define PM_QOS_DEV_LAT_DEFAULT_VALUE            0
  29
  30 struct pm_qos_request {
  31         struct plist_node node;
  32         int pm_qos_class;
  33         struct delayed_work work; /* for pm_qos_update_request_timeout */
  34 };
  35
  36 struct dev_pm_qos_request {
  37         struct plist_node node;
  38         struct device *dev;
  39 };
  40
  41 enum pm_qos_type {
  42         PM_QOS_UNITIALIZED,
  43         PM_QOS_MAX,             /* return the largest value */
  44         PM_QOS_MIN              /* return the smallest value */
  45 };
  46
  47 /*
  48  * Note: The lockless read path depends on the CPU accessing
  49  * target_value atomically.  Atomic access is only guaranteed on all CPU
  50  * types linux supports for 32 bit quantites
  51  */
  52 struct pm_qos_constraints {
  53         struct plist_head list;
  54         s32 target_value;       /* Do not change to 64 bit */
  55         s32 default_value;
  56         enum pm_qos_type type;
  57         struct blocking_notifier_head *notifiers;
  58 };
  59
  60 /* Action requested to pm_qos_update_target */
  61 enum pm_qos_req_action {
  62         PM_QOS_ADD_REQ,         /* Add a new request */
  63         PM_QOS_UPDATE_REQ,      /* Update an existing request */
  64         PM_QOS_REMOVE_REQ       /* Remove an existing request */
  65 };
  66
  67 static inline int dev_pm_qos_request_active(struct dev_pm_qos_request *req)
  68 {
  69         return req->dev != NULL;
  70 }
  71
  72 int pm_qos_update_target(struct pm_qos_constraints *c, struct plist_node *node,
  73                          enum pm_qos_req_action action, int value);
  74 void pm_qos_add_request(struct pm_qos_request *req, int pm_qos_class,
  75                         s32 value);
  76 void pm_qos_update_request(struct pm_qos_request *req,
  77                            s32 new_value);
  78 void pm_qos_update_request_timeout(struct pm_qos_request *req,
  79                                    s32 new_value, unsigned long timeout_us);
  80 void pm_qos_remove_request(struct pm_qos_request *req);
  81
  82 int pm_qos_request(int pm_qos_class);
  83 int pm_qos_add_notifier(int pm_qos_class, struct notifier_block *notifier);
  84 int pm_qos_remove_notifier(int pm_qos_class, struct notifier_block *notifier);
  85 int pm_qos_request_active(struct pm_qos_request *req);
  86 s32 pm_qos_read_value(struct pm_qos_constraints *c);
  87
  88 #ifdef CONFIG_PM
  89 s32 __dev_pm_qos_read_value(struct device *dev);
  90 s32 dev_pm_qos_read_value(struct device *dev);
  91 int dev_pm_qos_add_request(struct device *dev, struct dev_pm_qos_request *req,
  92                            s32 value);
  93 int dev_pm_qos_update_request(struct dev_pm_qos_request *req, s32 new_value);
  94 int dev_pm_qos_remove_request(struct dev_pm_qos_request *req);
  95 int dev_pm_qos_add_notifier(struct device *dev,
  96                             struct notifier_block *notifier);
  97 int dev_pm_qos_remove_notifier(struct device *dev,
  98                                struct notifier_block *notifier);
  99 int dev_pm_qos_add_global_notifier(struct notifier_block *notifier);
 100 int dev_pm_qos_remove_global_notifier(struct notifier_block *notifier);
 101 void dev_pm_qos_constraints_init(struct device *dev);
 102 void dev_pm_qos_constraints_destroy(struct device *dev);
 103 int dev_pm_qos_add_ancestor_request(struct device *dev,
 104                                     struct dev_pm_qos_request *req, s32 value);
 105 #else
 106 static inline s32 __dev_pm_qos_read_value(struct device *dev)
 107                         { return 0; }
 108 static inline s32 dev_pm_qos_read_value(struct device *dev)
 109                         { return 0; }
 110 static inline int dev_pm_qos_add_request(struct device *dev,
 111                                          struct dev_pm_qos_request *req,
 112                                          s32 value)
 113                         { return 0; }
 114 static inline int dev_pm_qos_update_request(struct dev_pm_qos_request *req,
 115                                             s32 new_value)
 116                         { return 0; }
 117 static inline int dev_pm_qos_remove_request(struct dev_pm_qos_request *req)
 118                         { return 0; }
 119 static inline int dev_pm_qos_add_notifier(struct device *dev,
 120                                           struct notifier_block *notifier)
 121                         { return 0; }
 122 static inline int dev_pm_qos_remove_notifier(struct device *dev,
 123                                              struct notifier_block *notifier)
 124                         { return 0; }
 125 static inline int dev_pm_qos_add_global_notifier(
 126                                         struct notifier_block *notifier)
 127                         { return 0; }
 128 static inline int dev_pm_qos_remove_global_notifier(
 129                                         struct notifier_block *notifier)
 130                         { return 0; }
 131 static inline void dev_pm_qos_constraints_init(struct device *dev)
 132 {
 133         dev->power.power_state = PMSG_ON;
 134 }
 135 static inline void dev_pm_qos_constraints_destroy(struct device *dev)
 136 {
 137         dev->power.power_state = PMSG_INVALID;
 138 }
 139 static inline int dev_pm_qos_add_ancestor_request(struct device *dev,
 140                                     struct dev_pm_qos_request *req, s32 value)
 141                         { return 0; }
 142 #endif
 143
 144 #ifdef CONFIG_PM_RUNTIME
 145 int dev_pm_qos_expose_latency_limit(struct device *dev, s32 value);
 146 void dev_pm_qos_hide_latency_limit(struct device *dev);
 147 #else
 148 static inline int dev_pm_qos_expose_latency_limit(struct device *dev, s32 value)
 149                         { return 0; }
 150 static inline void dev_pm_qos_hide_latency_limit(struct device *dev) {}
 151 #endif
 152
 153 #endif