OPP: Create separate kref for static OPPs list

The static OPPs don't always get freed with the OPP table, it can happen
before that as well. For example, if the OPP table is first created
using helpers like dev_pm_opp_set_supported_hw() and the OPPs are
created at a later point. Now when the OPPs are removed, the OPP table
stays until the time dev_pm_opp_put_supported_hw() is called.

Later patches will streamline the freeing of OPP table and that requires
the static OPPs to get freed with help of a separate kernel reference.
This patch prepares for that by creating a separate kref for static OPPs
list.

Tested-by: Niklas Cassel <niklas.cassel@linaro.org>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>

1 files changed, 32 insertions, 1 deletions

diff --git a/drivers/opp/core.c b/drivers/opp/core.c
index 2a6976265580..b555121b878b 100644
--- a/drivers/opp/core.c
+++ b/drivers/opp/core.c
@@ -892,6 +892,33 @@ static void _opp_table_kref_release(struct kref *kref)
 	mutex_unlock(&opp_table_lock);
 }
 
+void _opp_remove_all_static(struct opp_table *opp_table)
+{
+	struct dev_pm_opp *opp, *tmp;
+
+	list_for_each_entry_safe(opp, tmp, &opp_table->opp_list, node) {
+		if (!opp->dynamic)
+			dev_pm_opp_put(opp);
+	}
+
+	opp_table->parsed_static_opps = false;
+}
+
+static void _opp_table_list_kref_release(struct kref *kref)
+{
+	struct opp_table *opp_table = container_of(kref, struct opp_table,
+						   list_kref);
+
+	_opp_remove_all_static(opp_table);
+	mutex_unlock(&opp_table_lock);
+}
+
+void _put_opp_list_kref(struct opp_table *opp_table)
+{
+	kref_put_mutex(&opp_table->list_kref, _opp_table_list_kref_release,
+		       &opp_table_lock);
+}
+
 void dev_pm_opp_put_opp_table(struct opp_table *opp_table)
 {
 	kref_put_mutex(&opp_table->kref, _opp_table_kref_release,
@@ -1746,8 +1773,11 @@ void _dev_pm_opp_remove_table(struct opp_table *opp_table, struct device *dev,
 	/* Find if opp_table manages a single device */
 	if (list_is_singular(&opp_table->dev_list)) {
 		/* Free static OPPs */
+		_put_opp_list_kref(opp_table);
+
+		/* Free dynamic OPPs */
 		list_for_each_entry_safe(opp, tmp, &opp_table->opp_list, node) {
-			if (remove_all || !opp->dynamic)
+			if (remove_all)
 				dev_pm_opp_put(opp);
 		}
 
@@ -1758,6 +1788,7 @@ void _dev_pm_opp_remove_table(struct opp_table *opp_table, struct device *dev,
 		if (opp_table->genpd_performance_state)
 			dev_pm_genpd_set_performance_state(dev, 0);
 	} else {
+		_put_opp_list_kref(opp_table);
 		_remove_opp_dev(_find_opp_dev(dev, opp_table), opp_table);
 	}