MA-19967 Revert "MA-19337 Revert "PM / Domains: Support enter deepest state...

MA-19967 Revert "MA-19337 Revert "PM / Domains: Support enter deepest state for multiple states domains""

The last time it was reverted, because of structure changes that
blocks gki. To fix [8QM & 8QXP] Power consumption increased in
suspend mode, I plan to use a CONFIG to distinguish 8m* and 8q*.

This reverts commit 0c6748b7.

Change-Id: Ifce0f9d592e96ba691042e45f41ad3392b8a341f

drivers/base/power/domain.c

@@ -1027,7 +1027,17 @@ static void genpd_sync_power_off(struct generic_pm_domain *genpd, bool use_lock,
 {
 	struct gpd_link *link;
 
-	if (!genpd_status_on(genpd) || genpd_is_always_on(genpd))
+	/*
+	 * Give the power domain a chance to switch to the deepest state in
+	 * case it's already off but in an intermediate low power state.
+	 */
+	genpd->state_idx_saved = genpd->state_idx;
+
+	if (genpd_is_always_on(genpd))
+		return;
+
+	if (!genpd_status_on(genpd) &&
+	    genpd->state_idx == (genpd->state_count - 1))
 		return;
 
 	if (genpd->suspended_count != genpd->device_count)
@@ -1038,6 +1048,9 @@ static void genpd_sync_power_off(struct generic_pm_domain *genpd, bool use_lock,
 	if (_genpd_power_off(genpd, false))
 		return;
 
+	if (genpd->status == GENPD_STATE_OFF)
+		return;
+
 	genpd->status = GENPD_STATE_OFF;
 
 	list_for_each_entry(link, &genpd->child_links, child_node) {
@@ -1084,6 +1097,9 @@ static void genpd_sync_power_on(struct generic_pm_domain *genpd, bool use_lock,
 	}
 
 	_genpd_power_on(genpd, false);
+	/* restore save power domain state after resume */
+	genpd->state_idx = genpd->state_idx_saved;
+
 	genpd->status = GENPD_STATE_ON;
 }
 

include/linux/pm_domain.h

@@ -160,6 +160,7 @@ struct generic_pm_domain {
 		};
 	};
 
+	unsigned int state_idx_saved; /* saved power state for recovery after system suspend/resume */
 };
 
 static inline struct generic_pm_domain *pd_to_genpd(struct dev_pm_domain *pd)