1 files changed, 79 insertions, 2 deletions

diff --git a/drivers/opp/of.c b/drivers/opp/of.c
index b5605196122a..ffaeefef98ce 100644
--- a/drivers/opp/of.c
+++ b/drivers/opp/of.c
@@ -259,6 +259,77 @@ void _of_clear_opp_table(struct opp_table *opp_table)
 	_opp_table_free_required_tables(opp_table);
 }
 
+/*
+ * Release all resources previously acquired with a call to
+ * _of_opp_alloc_required_opps().
+ */
+void _of_opp_free_required_opps(struct opp_table *opp_table,
+				struct dev_pm_opp *opp)
+{
+	struct dev_pm_opp **required_opps = opp->required_opps;
+	int i;
+
+	if (!required_opps)
+		return;
+
+	for (i = 0; i < opp_table->required_opp_count; i++) {
+		if (!required_opps[i])
+			break;
+
+		/* Put the reference back */
+		dev_pm_opp_put(required_opps[i]);
+	}
+
+	kfree(required_opps);
+	opp->required_opps = NULL;
+}
+
+/* Populate all required OPPs which are part of "required-opps" list */
+static int _of_opp_alloc_required_opps(struct opp_table *opp_table,
+				       struct dev_pm_opp *opp)
+{
+	struct dev_pm_opp **required_opps;
+	struct opp_table *required_table;
+	struct device_node *np;
+	int i, ret, count = opp_table->required_opp_count;
+
+	if (!count)
+		return 0;
+
+	required_opps = kcalloc(count, sizeof(*required_opps), GFP_KERNEL);
+	if (!required_opps)
+		return -ENOMEM;
+
+	opp->required_opps = required_opps;
+
+	for (i = 0; i < count; i++) {
+		required_table = opp_table->required_opp_tables[i];
+
+		np = of_parse_required_opp(opp->np, i);
+		if (unlikely(!np)) {
+			ret = -ENODEV;
+			goto free_required_opps;
+		}
+
+		required_opps[i] = _find_opp_of_np(required_table, np);
+		of_node_put(np);
+
+		if (!required_opps[i]) {
+			pr_err("%s: Unable to find required OPP node: %pOF (%d)\n",
+			       __func__, opp->np, i);
+			ret = -ENODEV;
+			goto free_required_opps;
+		}
+	}
+
+	return 0;
+
+free_required_opps:
+	_of_opp_free_required_opps(opp_table, opp);
+
+	return ret;
+}
+
 static bool _opp_is_supported(struct device *dev, struct opp_table *opp_table,
 			      struct device_node *np)
 {
@@ -503,6 +574,10 @@ static struct dev_pm_opp *_opp_add_static_v2(struct opp_table *opp_table,
 	new_opp->dynamic = false;
 	new_opp->available = true;
 
+	ret = _of_opp_alloc_required_opps(opp_table, new_opp);
+	if (ret)
+		goto free_opp;
+
 	if (!of_property_read_u32(np, "clock-latency-ns", &val))
 		new_opp->clock_latency_ns = val;
 
@@ -510,14 +585,14 @@ static struct dev_pm_opp *_opp_add_static_v2(struct opp_table *opp_table,
 
 	ret = opp_parse_supplies(new_opp, dev, opp_table);
 	if (ret)
-		goto free_opp;
+		goto free_required_opps;
 
 	ret = _opp_add(dev, new_opp, opp_table, rate_not_available);
 	if (ret) {
 		/* Don't return error for duplicate OPPs */
 		if (ret == -EBUSY)
 			ret = 0;
-		goto free_opp;
+		goto free_required_opps;
 	}
 
 	/* OPP to select on device suspend */
@@ -547,6 +622,8 @@ static struct dev_pm_opp *_opp_add_static_v2(struct opp_table *opp_table,
 	blocking_notifier_call_chain(&opp_table->head, OPP_EVENT_ADD, new_opp);
 	return new_opp;
 
+free_required_opps:
+	_of_opp_free_required_opps(opp_table, new_opp);
 free_opp:
 	_opp_free(new_opp);