pmdomain: core: Allow power-off for out-of-band wakeup-capable devices

Currently, if a device is configured as a system wakeup source, the PM
domain core avoids powering off its power domain during system-wide
suspend. However, this can lead to unnecessary power consumption,
especially for devices whose wakeup logic resides in an always-on domain,
i.e., devices with out-of-band wakeup capability.

To address this, add a check for device_out_band_wakeup() in
genpd_finish_suspend(). If the device supports out-of-band wakeup, its
power domain can be safely powered off, just like regular devices without
wakeup enabled. And same check in genpd_finish_resume().

This change improves power efficiency without compromising wakeup
functionality.

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>

Author: MrVan

drivers/pmdomain/core.c

@@ -1545,7 +1545,8 @@ static int genpd_finish_suspend(struct device *dev,
 	if (ret)
 		return ret;
 
-	if (device_awake_path(dev) && genpd_is_active_wakeup(genpd))
+	if (device_awake_path(dev) && genpd_is_active_wakeup(genpd) &&
+	    !device_out_band_wakeup(dev))
 		return 0;
 
 	if (genpd->dev_ops.stop && genpd->dev_ops.start &&
@@ -1600,7 +1601,8 @@ static int genpd_finish_resume(struct device *dev,
 	if (IS_ERR(genpd))
 		return -EINVAL;
 
-	if (device_awake_path(dev) && genpd_is_active_wakeup(genpd))
+	if (device_awake_path(dev) && genpd_is_active_wakeup(genpd) &&
+	    !device_out_band_wakeup(dev))
 		return resume_noirq(dev);
 
 	genpd_lock(genpd);