[PATCH 3/3] PM / Domains: Run late/early device suspend callbacks at the right time

["Rafael J. Wysocki" <rjw@sisk.pl>]

From: Rafael J. Wysocki <rjw@sisk.pl>

After the introduction of the late/early phases of device
suspend/resume during system-wide power transitions it is possible
to make the generic PM domains code execute its default late/early
device suspend/resume callbacks during those phases instead of the
corresponding _noirq phases.  The _noirq device suspend/resume
phases were only used for executing those callbacks, because this
was the only way it could be done, but now we can do better.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
---
 drivers/base/power/domain.c |  157 +++++++++++++++++++++++++++++++-------------
 1 file changed, 111 insertions(+), 46 deletions(-)

Index: linux/drivers/base/power/domain.c
===================================================================
--- linux.orig/drivers/base/power/domain.c
+++ linux/drivers/base/power/domain.c
@@ -820,17 +820,16 @@ static int pm_genpd_suspend(struct devic
 }
 
 /**
- * pm_genpd_suspend_noirq - Late suspend of a device from an I/O PM domain.
+ * pm_genpd_suspend_late - Late suspend of a device from an I/O PM domain.
  * @dev: Device to suspend.
  *
  * Carry out a late suspend of a device under the assumption that its
  * pm_domain field points to the domain member of an object of type
  * struct generic_pm_domain representing a PM domain consisting of I/O devices.
  */
-static int pm_genpd_suspend_noirq(struct device *dev)
+static int pm_genpd_suspend_late(struct device *dev)
 {
 	struct generic_pm_domain *genpd;
-	int ret;
 
 	dev_dbg(dev, "%s()\n", __func__);
 
@@ -838,14 +837,28 @@ static int pm_genpd_suspend_noirq(struct
 	if (IS_ERR(genpd))
 		return -EINVAL;
 
-	if (genpd->suspend_power_off)
-		return 0;
+	return genpd->suspend_power_off ? 0 : genpd_suspend_late(genpd, dev);
+}
 
-	ret = genpd_suspend_late(genpd, dev);
-	if (ret)
-		return ret;
+/**
+ * pm_genpd_suspend_noirq - Completion of suspend of device in an I/O PM domain.
+ * @dev: Device to suspend.
+ *
+ * Stop the device and remove power from the domain if all devices in it have
+ * been stopped.
+ */
+static int pm_genpd_suspend_noirq(struct device *dev)
+{
+	struct generic_pm_domain *genpd;
 
-	if (dev->power.wakeup_path && genpd_dev_active_wakeup(genpd, dev))
+	dev_dbg(dev, "%s()\n", __func__);
+
+	genpd = dev_to_genpd(dev);
+	if (IS_ERR(genpd))
+		return -EINVAL;
+
+	if (genpd->suspend_power_off
+	    || (dev->power.wakeup_path && genpd_dev_active_wakeup(genpd, dev)))
 		return 0;
 
 	genpd_stop_dev(genpd, dev);
@@ -862,13 +875,10 @@ static int pm_genpd_suspend_noirq(struct
 }
 
 /**
- * pm_genpd_resume_noirq - Early resume of a device from an I/O power domain.
+ * pm_genpd_resume_noirq - Start of resume of device in an I/O PM domain.
  * @dev: Device to resume.
  *
- * Carry out an early resume of a device under the assumption that its
- * pm_domain field points to the domain member of an object of type
- * struct generic_pm_domain representing a power domain consisting of I/O
- * devices.
+ * Restore power to the device's PM domain, if necessary, and start the device.
  */
 static int pm_genpd_resume_noirq(struct device *dev)
 {
@@ -890,13 +900,34 @@ static int pm_genpd_resume_noirq(struct
 	 */
 	pm_genpd_poweron(genpd);
 	genpd->suspended_count--;
-	genpd_start_dev(genpd, dev);
 
-	return genpd_resume_early(genpd, dev);
+	return genpd_start_dev(genpd, dev);
 }
 
 /**
- * pm_genpd_resume - Resume a device belonging to an I/O power domain.
+ * pm_genpd_resume_early - Early resume of a device in an I/O PM domain.
+ * @dev: Device to resume.
+ *
+ * Carry out an early resume of a device under the assumption that its
+ * pm_domain field points to the domain member of an object of type
+ * struct generic_pm_domain representing a power domain consisting of I/O
+ * devices.
+ */
+static int pm_genpd_resume_early(struct device *dev)
+{
+	struct generic_pm_domain *genpd;
+
+	dev_dbg(dev, "%s()\n", __func__);
+
+	genpd = dev_to_genpd(dev);
+	if (IS_ERR(genpd))
+		return -EINVAL;
+
+	return genpd->suspend_power_off ? 0 : genpd_resume_early(genpd, dev);
+}
+
+/**
+ * pm_genpd_resume - Resume of device in an I/O PM domain.
  * @dev: Device to resume.
  *
  * Resume a device under the assumption that its pm_domain field points to the
@@ -917,7 +948,7 @@ static int pm_genpd_resume(struct device
 }
 
 /**
- * pm_genpd_freeze - Freeze a device belonging to an I/O power domain.
+ * pm_genpd_freeze - Freezing a device in an I/O PM domain.
  * @dev: Device to freeze.
  *
  * Freeze a device under the assumption that its pm_domain field points to the
@@ -938,7 +969,29 @@ static int pm_genpd_freeze(struct device
 }
 
 /**
- * pm_genpd_freeze_noirq - Late freeze of a device from an I/O power domain.
+ * pm_genpd_freeze_late - Late freeze of a device in an I/O PM domain.
+ * @dev: Device to freeze.
+ *
+ * Carry out a late freeze of a device under the assumption that its
+ * pm_domain field points to the domain member of an object of type
+ * struct generic_pm_domain representing a power domain consisting of I/O
+ * devices.
+ */
+static int pm_genpd_freeze_late(struct device *dev)
+{
+	struct generic_pm_domain *genpd;
+
+	dev_dbg(dev, "%s()\n", __func__);
+
+	genpd = dev_to_genpd(dev);
+	if (IS_ERR(genpd))
+		return -EINVAL;
+
+	return genpd->suspend_power_off ? 0 : genpd_freeze_late(genpd, dev);
+}
+
+/**
+ * pm_genpd_freeze_noirq - Completion of freezing a device in an I/O PM domain.
  * @dev: Device to freeze.
  *
  * Carry out a late freeze of a device under the assumption that its
@@ -949,7 +1002,6 @@ static int pm_genpd_freeze(struct device
 static int pm_genpd_freeze_noirq(struct device *dev)
 {
 	struct generic_pm_domain *genpd;
-	int ret;
 
 	dev_dbg(dev, "%s()\n", __func__);
 
@@ -957,20 +1009,31 @@ static int pm_genpd_freeze_noirq(struct
 	if (IS_ERR(genpd))
 		return -EINVAL;
 
-	if (genpd->suspend_power_off)
-		return 0;
+	return genpd->suspend_power_off ? 0 : genpd_stop_dev(genpd, dev);
+}
+
+/**
+ * pm_genpd_thaw_noirq - Early thaw of device in an I/O PM domain.
+ * @dev: Device to thaw.
+ *
+ * Start the device, unless power has been removed from the domain already
+ * before the system transition.
+ */
+static int pm_genpd_thaw_noirq(struct device *dev)
+{
+	struct generic_pm_domain *genpd;
 
-	ret = genpd_freeze_late(genpd, dev);
-	if (ret)
-		return ret;
+	dev_dbg(dev, "%s()\n", __func__);
 
-	genpd_stop_dev(genpd, dev);
+	genpd = dev_to_genpd(dev);
+	if (IS_ERR(genpd))
+		return -EINVAL;
 
-	return 0;
+	return genpd->suspend_power_off ? 0 : genpd_start_dev(genpd, dev);
 }
 
 /**
- * pm_genpd_thaw_noirq - Early thaw of a device from an I/O power domain.
+ * pm_genpd_thaw_early - Early thaw of device in an I/O PM domain.
  * @dev: Device to thaw.
  *
  * Carry out an early thaw of a device under the assumption that its
@@ -978,7 +1041,7 @@ static int pm_genpd_freeze_noirq(struct
  * struct generic_pm_domain representing a power domain consisting of I/O
  * devices.
  */
-static int pm_genpd_thaw_noirq(struct device *dev)
+static int pm_genpd_thaw_early(struct device *dev)
 {
 	struct generic_pm_domain *genpd;
 
@@ -988,12 +1051,7 @@ static int pm_genpd_thaw_noirq(struct de
 	if (IS_ERR(genpd))
 		return -EINVAL;
 
-	if (genpd->suspend_power_off)
-		return 0;
-
-	genpd_start_dev(genpd, dev);
-
-	return genpd_thaw_early(genpd, dev);
+	return genpd->suspend_power_off ? 0 : genpd_thaw_early(genpd, dev);
 }
 
 /**
@@ -1018,13 +1076,11 @@ static int pm_genpd_thaw(struct device *
 }
 
 /**
- * pm_genpd_restore_noirq - Early restore of a device from an I/O power domain.
+ * pm_genpd_restore_noirq - Start of restore of device in an I/O PM domain.
  * @dev: Device to resume.
  *
- * Carry out an early restore of a device under the assumption that its
- * pm_domain field points to the domain member of an object of type
- * struct generic_pm_domain representing a power domain consisting of I/O
- * devices.
+ * Make sure the domain will be in the same power state as before the
+ * hibernation the system is resuming from and start the device if necessary.
  */
 static int pm_genpd_restore_noirq(struct device *dev)
 {
@@ -1054,9 +1110,8 @@ static int pm_genpd_restore_noirq(struct
 
 	pm_genpd_poweron(genpd);
 	genpd->suspended_count--;
-	genpd_start_dev(genpd, dev);
 
-	return genpd_resume_early(genpd, dev);
+	return genpd_start_dev(genpd, dev);
 }
 
 /**
@@ -1099,11 +1154,15 @@ static void pm_genpd_complete(struct dev
 
 #define pm_genpd_prepare		NULL
 #define pm_genpd_suspend		NULL
+#define pm_genpd_suspend_late		NULL
 #define pm_genpd_suspend_noirq		NULL
+#define pm_genpd_resume_early		NULL
 #define pm_genpd_resume_noirq		NULL
 #define pm_genpd_resume			NULL
 #define pm_genpd_freeze			NULL
+#define pm_genpd_freeze_late		NULL
 #define pm_genpd_freeze_noirq		NULL
+#define pm_genpd_thaw_early		NULL
 #define pm_genpd_thaw_noirq		NULL
 #define pm_genpd_thaw			NULL
 #define pm_genpd_restore_noirq		NULL
@@ -1450,7 +1509,7 @@ static int pm_genpd_default_suspend_late
 {
 	int (*cb)(struct device *__dev) = dev_gpd_data(dev)->ops.suspend_late;
 
-	return cb ? cb(dev) : pm_generic_suspend_noirq(dev);
+	return cb ? cb(dev) : pm_generic_suspend_late(dev);
 }
 
 /**
@@ -1461,7 +1520,7 @@ static int pm_genpd_default_resume_early
 {
 	int (*cb)(struct device *__dev) = dev_gpd_data(dev)->ops.resume_early;
 
-	return cb ? cb(dev) : pm_generic_resume_noirq(dev);
+	return cb ? cb(dev) : pm_generic_resume_early(dev);
 }
 
 /**
@@ -1494,7 +1553,7 @@ static int pm_genpd_default_freeze_late(
 {
 	int (*cb)(struct device *__dev) = dev_gpd_data(dev)->ops.freeze_late;
 
-	return cb ? cb(dev) : pm_generic_freeze_noirq(dev);
+	return cb ? cb(dev) : pm_generic_freeze_late(dev);
 }
 
 /**
@@ -1505,7 +1564,7 @@ static int pm_genpd_default_thaw_early(s
 {
 	int (*cb)(struct device *__dev) = dev_gpd_data(dev)->ops.thaw_early;
 
-	return cb ? cb(dev) : pm_generic_thaw_noirq(dev);
+	return cb ? cb(dev) : pm_generic_thaw_early(dev);
 }
 
 /**
@@ -1564,16 +1623,22 @@ void pm_genpd_init(struct generic_pm_dom
 	genpd->domain.ops.runtime_idle = pm_generic_runtime_idle;
 	genpd->domain.ops.prepare = pm_genpd_prepare;
 	genpd->domain.ops.suspend = pm_genpd_suspend;
+	genpd->domain.ops.suspend_late = pm_genpd_suspend_late;
 	genpd->domain.ops.suspend_noirq = pm_genpd_suspend_noirq;
 	genpd->domain.ops.resume_noirq = pm_genpd_resume_noirq;
+	genpd->domain.ops.resume_early = pm_genpd_resume_early;
 	genpd->domain.ops.resume = pm_genpd_resume;
 	genpd->domain.ops.freeze = pm_genpd_freeze;
+	genpd->domain.ops.freeze_late = pm_genpd_freeze_late;
 	genpd->domain.ops.freeze_noirq = pm_genpd_freeze_noirq;
 	genpd->domain.ops.thaw_noirq = pm_genpd_thaw_noirq;
+	genpd->domain.ops.thaw_early = pm_genpd_thaw_early;
 	genpd->domain.ops.thaw = pm_genpd_thaw;
 	genpd->domain.ops.poweroff = pm_genpd_suspend;
+	genpd->domain.ops.poweroff_late = pm_genpd_suspend_late;
 	genpd->domain.ops.poweroff_noirq = pm_genpd_suspend_noirq;
 	genpd->domain.ops.restore_noirq = pm_genpd_restore_noirq;
+	genpd->domain.ops.restore_early = pm_genpd_resume_early;
 	genpd->domain.ops.restore = pm_genpd_resume;
 	genpd->domain.ops.complete = pm_genpd_complete;
 	genpd->dev_ops.save_state = pm_genpd_default_save_state;