PM / Domains: Use power.sybsys_data to reduce overhead

Currently pm_genpd_runtime_resume() has to walk the list of devices
from the device's PM domain to find the corresponding device list
object containing the need_restore field to check if the driver's
.runtime_resume() callback should be executed for the device.
This is suboptimal and can be simplified by using power.sybsys_data
to store device information used by the generic PM domains code.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>

1 files changed, 10 insertions, 0 deletions

diff --git a/include/linux/pm_runtime.h b/include/linux/pm_runtime.h
index 6b90630e3c98..a5a41a850efb 100644
--- a/include/linux/pm_runtime.h
+++ b/include/linux/pm_runtime.h
@@ -258,6 +258,12 @@ struct pm_clk_notifier_block {
 };
 
 #ifdef CONFIG_PM_CLK
+static inline bool pm_clk_no_clocks(struct device *dev)
+{
+	return dev && dev->power.subsys_data
+		&& list_empty(&dev->power.subsys_data->clock_list);
+}
+
 extern void pm_clk_init(struct device *dev);
 extern int pm_clk_create(struct device *dev);
 extern void pm_clk_destroy(struct device *dev);
@@ -266,6 +272,10 @@ extern void pm_clk_remove(struct device *dev, const char *con_id);
 extern int pm_clk_suspend(struct device *dev);
 extern int pm_clk_resume(struct device *dev);
 #else
+static inline bool pm_clk_no_clocks(struct device *dev)
+{
+	return true;
+}
 static inline void pm_clk_init(struct device *dev)
 {
 }