power: Platform-level low power state stats

Add interface to export export platform-level power stats
to BatteryStatsService.

Bug: 26564574

Change-Id: Ibd452c46d91b0055bc5aa0e6b2cc8ee7b428ea31

1 files changed, 159 insertions, 0 deletions

diff --git a/include/hardware/power.h b/include/hardware/power.h
index cc6f5b93..c451d670 100644
--- a/include/hardware/power.h
+++ b/include/hardware/power.h
@@ -17,6 +17,7 @@
 #ifndef ANDROID_INCLUDE_HARDWARE_POWER_H
 #define ANDROID_INCLUDE_HARDWARE_POWER_H
 
+#include <stdbool.h>
 #include <stdint.h>
 #include <sys/cdefs.h>
 #include <sys/types.h>
@@ -29,6 +30,7 @@ __BEGIN_DECLS
 #define POWER_MODULE_API_VERSION_0_2  HARDWARE_MODULE_API_VERSION(0, 2)
 #define POWER_MODULE_API_VERSION_0_3  HARDWARE_MODULE_API_VERSION(0, 3)
 #define POWER_MODULE_API_VERSION_0_4  HARDWARE_MODULE_API_VERSION(0, 4)
+#define POWER_MODULE_API_VERSION_0_5  HARDWARE_MODULE_API_VERSION(0, 5)
 
 /**
  * The id of this module
@@ -36,6 +38,18 @@ __BEGIN_DECLS
 #define POWER_HARDWARE_MODULE_ID "power"
 
 /*
+ * Platform-level sleep state stats.
+ * Maximum length of Platform-level sleep state name.
+ */
+#define POWER_STATE_NAME_MAX_LENGTH 100
+
+/*
+ * Platform-level sleep state stats.
+ * Maximum length of Platform-level sleep state voter name.
+ */
+#define POWER_STATE_VOTER_NAME_MAX_LENGTH 100
+
+/*
  * Power hint identifiers passed to (*powerHint)
  */
 
@@ -56,6 +70,91 @@ typedef enum {
     POWER_FEATURE_DOUBLE_TAP_TO_WAKE = 0x00000001
 } feature_t;
 
+/*
+ * Platform-level sleep state stats:
+ * power_state_voter_t struct is useful for describing the individual voters when a
+ * Platform-level sleep state is chosen by aggregation of votes from multiple
+ * clients/system conditions.
+ *
+ * This helps in attirbuting what in the device is blocking the device from
+ * entering the lowest Platform-level sleep state.
+ */
+typedef struct {
+    /*
+     * Name of the voter.
+     */
+     char name[POWER_STATE_VOTER_NAME_MAX_LENGTH];
+
+    /*
+     * Total time in msec the voter voted for the platform sleep state since boot.
+     */
+     uint64_t total_time_in_msec_voted_for_since_boot;
+
+    /*
+     * Number of times the voter voted for the platform sleep state since boot.
+     */
+     uint64_t total_number_of_times_voted_since_boot;
+} power_state_voter_t;
+
+/*
+ * Platform-level sleep state stats:
+ * power_state_platform_sleep_state_t represents the Platform-level sleep state the
+ * device is capable of getting into.
+ *
+ * SoCs usually have more than one Platform-level sleep state.
+ *
+ * The caller calls the get_number_of_platform_modes function to figure out the size
+ * of power_state_platform_sleep_state_t array where each array element represents
+ * a specific Platform-level sleep state.
+ *
+ * Higher the index deeper the state is i.e. lesser steady-state power is consumed
+ * by the platform to be resident in that state.
+ *
+ * Caller allocates power_state_voter_t *voters for each Platform-level sleep state by
+ * calling get_voter_list.
+ */
+typedef struct {
+    /*
+     * Platform-level Sleep state name.
+     */
+    char name[POWER_STATE_NAME_MAX_LENGTH];
+
+    /*
+     * Time spent in msec at this platform-level sleep state since boot.
+     */
+    uint64_t residency_in_msec_since_boot;
+
+    /*
+     * Total number of times system entered this state.
+     */
+    uint64_t total_transitions;
+
+    /*
+     * This platform-level sleep state can only be reached during system suspend.
+     */
+    bool supported_only_in_suspend;
+
+    /*
+     * The following fields are useful if the Platform-level sleep state
+     * is chosen by aggregation votes from multiple clients/system conditions.
+     * All the voters have to say yes or all the system conditions need to be
+     * met to enter a platform-level sleep state.
+     *
+     * Setting number_of_voters to zero implies either the info is not available
+     * or the system does not follow a voting mechanism to choose this
+     * Platform-level sleep state.
+     */
+    uint32_t number_of_voters;
+
+    /*
+     * Voter list - Has to be allocated by the caller.
+     *
+     * Caller allocates power_state_voter_t *voters for each Platform-level sleep state
+     * by calling get_voter_list.
+     */
+    power_state_voter_t *voters;
+} power_state_platform_sleep_state_t;
+
 /**
  * Every hardware module must have a data structure named HAL_MODULE_INFO_SYM
  * and the fields of this data structure must begin with hw_module_t
@@ -69,6 +168,10 @@ typedef struct power_module {
      * startup, such as to set default cpufreq parameters.  This is
      * called only by the Power HAL instance loaded by
      * PowerManagerService.
+     *
+     * Platform-level sleep state stats:
+     * Can Also be used to initiate device specific Platform-level
+     * Sleep state nodes from version 0.5 onwards.
      */
     void (*init)(struct power_module *module);
 
@@ -166,6 +269,62 @@ typedef struct power_module {
      */
     void (*setFeature)(struct power_module *module, feature_t feature, int state);
 
+    /*
+     * Platform-level sleep state stats:
+     * Report cumulative info on the statistics on platform-level sleep states since boot.
+     *
+     * Caller of the function queries the get_number_of_sleep_states and allocates the
+     * memory for the power_state_platform_sleep_state_t *list before calling this function.
+     *
+     * power_stats module is responsible to assign values to all the fields as
+     * necessary.
+     *
+     * Higher the index deeper the state is i.e. lesser steady-state power is consumed
+     * by the platform to be resident in that state.
+     *
+     * The function returns 0 on success or negative value -errno on error.
+     * EINVAL - *list is NULL.
+     * EIO - filesystem nodes access error.
+     *
+     * availability: version 0.5
+     */
+    int (*get_platform_low_power_stats)(struct power_module *module,
+        power_state_platform_sleep_state_t *list);
+
+    /*
+     * Platform-level sleep state stats:
+     * This function is called to determine the number of platform-level sleep states
+     * for get_platform_low_power_stats.
+     *
+     * The value returned by this function is used to allocate memory for
+     * power_state_platform_sleep_state_t *list for get_platform_low_power_stats.
+     *
+     * The number of parameters must not change for successive calls.
+     *
+     * Return number of parameters on success or negative value -errno on error.
+     * EIO - filesystem nodes access error.
+     *
+     * availability: version 0.5
+     */
+    ssize_t (*get_number_of_platform_modes)(struct power_module *module);
+
+    /*
+     * Platform-level sleep state stats:
+     * Provides the number of voters for each of the Platform-level sleep state.
+     *
+     * Caller uses this function to allocate memory for the power_state_voter_t list.
+     *
+     * Caller has to allocate the space for the *voter array which is
+     * get_number_of_platform_modes() long.
+     *
+     * Return 0 on success or negative value -errno on error.
+     * EINVAL - *voter is NULL.
+     * EIO - filesystem nodes access error.
+     *
+     * availability: version 0.5
+     */
+    int (*get_voter_list)(struct power_module *module, size_t *voter);
+
 } power_module_t;