PM / Domains: Make it possible to use per-device domain callbacks

The current generic PM domains code requires that the same .stop(),
.start() and .active_wakeup() device callback routines be used for
all devices in the given domain, which is inflexible and may not
cover some specific use cases.  For this reason, make it possible to
use device specific .start()/.stop() and .active_wakeup() callback
routines by adding corresponding callback pointers to struct
generic_pm_domain_data.  Add a new helper routine,
pm_genpd_register_callbacks(), that can be used to populate
the new per-device callback pointers.

Modify the shmobile's power domains code to allow drivers to add
their own code to be run during the device stop and start operations
with the help of the new callback pointers.

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

1 files changed, 24 insertions, 3 deletions

diff --git a/include/linux/pm_domain.h b/include/linux/pm_domain.h
index 65633e5..8949d2d 100644
--- a/include/linux/pm_domain.h
+++ b/include/linux/pm_domain.h
@@ -23,6 +23,12 @@ struct dev_power_governor {
 	bool (*power_down_ok)(struct dev_pm_domain *domain);
 };
 
+struct gpd_dev_ops {
+	int (*start)(struct device *dev);
+	int (*stop)(struct device *dev);
+	bool (*active_wakeup)(struct device *dev);
+};
+
 struct generic_pm_domain {
 	struct dev_pm_domain domain;	/* PM domain operations */
 	struct list_head gpd_list_node;	/* Node in the global PM domains list */
@@ -45,9 +51,7 @@ struct generic_pm_domain {
 	bool dev_irq_safe;	/* Device callbacks are IRQ-safe */
 	int (*power_off)(struct generic_pm_domain *domain);
 	int (*power_on)(struct generic_pm_domain *domain);
-	int (*start_device)(struct device *dev);
-	int (*stop_device)(struct device *dev);
-	bool (*active_wakeup)(struct device *dev);
+	struct gpd_dev_ops dev_ops;
 };
 
 static inline struct generic_pm_domain *pd_to_genpd(struct dev_pm_domain *pd)
@@ -64,6 +68,7 @@ struct gpd_link {
 
 struct generic_pm_domain_data {
 	struct pm_domain_data base;
+	struct gpd_dev_ops ops;
 	bool need_restore;
 };
 
@@ -73,6 +78,11 @@ static inline struct generic_pm_domain_data *to_gpd_data(struct pm_domain_data *
 }
 
 #ifdef CONFIG_PM_GENERIC_DOMAINS
+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 int pm_genpd_remove_device(struct generic_pm_domain *genpd,
@@ -81,6 +91,8 @@ 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 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);
@@ -105,6 +117,15 @@ 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)
+{
+	return -ENOSYS;
+}
+static inline int pm_genpd_remove_callbacks(struct device *dev)
+{
+	return -ENOSYS;
+}
 static inline void pm_genpd_init(struct generic_pm_domain *genpd,
 				 struct dev_power_governor *gov, bool is_off) {}
 static inline int pm_genpd_poweron(struct generic_pm_domain *genpd)