PM: wakeup: Add out-of-band system wakeup support for devices

Some devices can wake up the system from suspend even when their power
domains are turned off. This is possible because their system-wakeup logic
resides in an always-on power domain - indicating that they support
out-of-band system wakeup.

Currently, PM domain core doesn't power off such devices if they are marked
as system wakeup sources. To better represent devices with out-of-band
wakeup capability, this patch introduces a new flag out_band_wakeup in
'struct dev_pm_info'.

Two helper APIs are added:
 - device_set_out_band_wakeup() - to mark a device as having out-of-band
   wakeup capability.
 - device_out_band_wakeup() - to query the flag.

Allow the PM core and drivers to distinguish between regular and
out-of-band wakeup sources, enable more accurate power management decision.

Signed-off-by: Peng Fan <peng.fan@nxp.com>
Reviewed-by: Dhruva Gole <d-gole@ti.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

diff --git a/drivers/base/power/main.c b/drivers/base/power/main.c
index e83503bdc1fdb83de20192745ca7e416fd556e04..bcfb170baca63c479006adb976ffcd9bc1855cd5 100644 (file)
--- a/drivers/base/power/main.c
+++ b/drivers/base/power/main.c
@@ -2126,6 +2126,7 @@ static int device_prepare(struct device *dev, pm_message_t state)
        device_lock(dev);
 
        dev->power.wakeup_path = false;
+       dev->power.out_band_wakeup = false;
 
        if (dev->power.no_pm_callbacks)
                goto unlock;

diff --git a/include/linux/pm.h b/include/linux/pm.h
index cc7b2dc28574c24ece2f651352d4d23ecaf15f31..5b28a4f2e87e2aa34acc709e146ce729acace344 100644 (file)
--- a/include/linux/pm.h
+++ b/include/linux/pm.h
@@ -684,6 +684,7 @@ struct dev_pm_info {
        bool                    smart_suspend:1;        /* Owned by the PM core */
        bool                    must_resume:1;          /* Owned by the PM core */
        bool                    may_skip_resume:1;      /* Set by subsystems */
+       bool                    out_band_wakeup:1;
        bool                    strict_midlayer:1;
 #else
        bool                    should_wakeup:1;

diff --git a/include/linux/pm_wakeup.h b/include/linux/pm_wakeup.h
index c838b4a30f876ef5a66972d16f461cfba9ff2814..41e8f344a20563898e827da62dd240b8cbe657d2 100644 (file)
--- a/include/linux/pm_wakeup.h
+++ b/include/linux/pm_wakeup.h
@@ -94,6 +94,16 @@ static inline void device_set_wakeup_path(struct device *dev)
        dev->power.wakeup_path = true;
 }
 
+static inline void device_set_out_band_wakeup(struct device *dev)
+{
+       dev->power.out_band_wakeup = true;
+}
+
+static inline bool device_out_band_wakeup(struct device *dev)
+{
+       return dev->power.out_band_wakeup;
+}
+
 /* drivers/base/power/wakeup.c */
 extern struct wakeup_source *wakeup_source_register(struct device *dev,
                                                    const char *name);
@@ -162,6 +172,13 @@ static inline bool device_wakeup_path(struct device *dev)
 
 static inline void device_set_wakeup_path(struct device *dev) {}
 
+static inline void device_set_out_band_wakeup(struct device *dev) {}
+
+static inline bool device_out_band_wakeup(struct device *dev)
+{
+       return false;
+}
+
 static inline void __pm_stay_awake(struct wakeup_source *ws) {}
 
 static inline void pm_stay_awake(struct device *dev) {}