PM / Domains: Add device stop governor function (v4)

Add a function deciding whether or not devices should be stopped in
pm_genpd_runtime_suspend() depending on their PM QoS constraints
and stop/start timing values.  Make it possible to add information
used by this function to device objects.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Magnus Damm <damm@opensource.se>

1 files changed, 55 insertions, 8 deletions

diff --git a/include/linux/pm_domain.h b/include/linux/pm_domain.h
index 10a197dce07e..f6745c213a57 100644
--- a/include/linux/pm_domain.h
+++ b/include/linux/pm_domain.h
@@ -21,6 +21,7 @@ enum gpd_status {
 
 struct dev_power_governor {
         bool (*power_down_ok)(struct dev_pm_domain *domain);
+        bool (*stop_ok)(struct device *dev);
 };
 
 struct gpd_dev_ops {
@@ -76,9 +77,16 @@ struct gpd_link {
         struct list_head slave_node;
 };
 
+struct gpd_timing_data {
+        s64 stop_latency_ns;
+        s64 start_latency_ns;
+        s64 break_even_ns;
+};
+
 struct generic_pm_domain_data {
         struct pm_domain_data base;
         struct gpd_dev_ops ops;
+        struct gpd_timing_data td;
         bool need_restore;
 };
 
@@ -93,20 +101,48 @@ static inline struct generic_pm_domain_data *dev_gpd_data(struct device *dev)
         return to_gpd_data(dev->power.subsys_data->domain_data);
 }
 
-extern int pm_genpd_add_device(struct generic_pm_domain *genpd,
-                               struct device *dev);
+extern struct dev_power_governor simple_qos_governor;
+
+extern struct generic_pm_domain *dev_to_genpd(struct device *dev);
+extern int __pm_genpd_add_device(struct generic_pm_domain *genpd,
+                                 struct device *dev,
+                                 struct gpd_timing_data *td);
+
+static inline int pm_genpd_add_device(struct generic_pm_domain *genpd,
+                                      struct device *dev)
+{
+        return __pm_genpd_add_device(genpd, dev, NULL);
+}
+
 extern int pm_genpd_remove_device(struct generic_pm_domain *genpd,
                                   struct device *dev);
 extern int pm_genpd_add_subdomain(struct generic_pm_domain *genpd,
                                   struct generic_pm_domain *new_subdomain);
 extern int pm_genpd_remove_subdomain(struct generic_pm_domain *genpd,
                                      struct generic_pm_domain *target);
-extern int pm_genpd_add_callbacks(struct device *dev, struct gpd_dev_ops *ops);
-extern int pm_genpd_remove_callbacks(struct device *dev);
+extern int pm_genpd_add_callbacks(struct device *dev,
+                                  struct gpd_dev_ops *ops,
+                                  struct gpd_timing_data *td);
+extern int __pm_genpd_remove_callbacks(struct device *dev, bool clear_td);
 extern void pm_genpd_init(struct generic_pm_domain *genpd,
                           struct dev_power_governor *gov, bool is_off);
+
 extern int pm_genpd_poweron(struct generic_pm_domain *genpd);
+
+extern bool default_stop_ok(struct device *dev);
+
 #else
+
+static inline struct generic_pm_domain *dev_to_genpd(struct device *dev)
+{
+        return ERR_PTR(-ENOSYS);
+}
+static inline int __pm_genpd_add_device(struct generic_pm_domain *genpd,
+                                        struct device *dev,
+                                        struct gpd_timing_data *td)
+{
+        return -ENOSYS;
+}
 static inline int pm_genpd_add_device(struct generic_pm_domain *genpd,
                                       struct device *dev)
 {
@@ -128,22 +164,33 @@ static inline int pm_genpd_remove_subdomain(struct generic_pm_domain *genpd,
         return -ENOSYS;
 }
 static inline int pm_genpd_add_callbacks(struct device *dev,
-                                         struct gpd_dev_ops *ops)
+                                         struct gpd_dev_ops *ops,
+                                         struct gpd_timing_data *td)
 {
         return -ENOSYS;
 }
-static inline int pm_genpd_remove_callbacks(struct device *dev)
+static inline int __pm_genpd_remove_callbacks(struct device *dev, bool clear_td)
 {
         return -ENOSYS;
 }
-static inline void pm_genpd_init(struct generic_pm_domain *genpd,
-                                 struct dev_power_governor *gov, bool is_off) {}
+static inline void pm_genpd_init(struct generic_pm_domain *genpd, bool is_off)
+{
+}
 static inline int pm_genpd_poweron(struct generic_pm_domain *genpd)
 {
         return -ENOSYS;
 }
+static inline bool default_stop_ok(struct device *dev)
+{
+        return false;
+}
 #endif
 
+static inline int pm_genpd_remove_callbacks(struct device *dev)
+{
+        return __pm_genpd_remove_callbacks(dev, true);
+}
+
 #ifdef CONFIG_PM_GENERIC_DOMAINS_RUNTIME
 extern void genpd_queue_power_off_work(struct generic_pm_domain *genpd);
 extern void pm_genpd_poweroff_unused(void);