PM / Domains: Add APIs to attach/detach a PM domain for a device

To maintain scalability let's add common methods to attach and detach
a PM domain for a device, dev_pm_domain_attach|detach().

Typically dev_pm_domain_attach() shall be invoked from subsystem level
code at the probe phase to try to attach a device to its PM domain.
The reversed actions may be done a the remove phase and then by
invoking dev_pm_domain_detach().

When attachment succeeds, the attach function should assign its
corresponding detach function to a new ->detach() callback added in the
struct dev_pm_domain.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Tested-by: Philipp Zabel <p.zabel@pengutronix.de>
Reviewed-by: Kevin Hilman <khilman@linaro.org>
Reviewed-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

1 files changed, 11 insertions, 0 deletions

diff --git a/include/linux/pm.h b/include/linux/pm.h
index 1022ba1..c4cbf48 100644
--- a/include/linux/pm.h
+++ b/include/linux/pm.h
@@ -622,6 +622,17 @@ struct dev_pm_domain {
 	void (*detach)(struct device *dev, bool power_off);
 };
 
+#ifdef CONFIG_PM
+extern int dev_pm_domain_attach(struct device *dev, bool power_on);
+extern void dev_pm_domain_detach(struct device *dev, bool power_off);
+#else
+static inline int dev_pm_domain_attach(struct device *dev, bool power_on)
+{
+	return -ENODEV;
+}
+static inline void dev_pm_domain_detach(struct device *dev, bool power_off) {}
+#endif
+
 /*
  * The PM_EVENT_ messages are also used by drivers implementing the legacy
  * suspend framework, based on the ->suspend() and ->resume() callbacks common