opp: Always add entries in dev_list with opp_table->lock held

The readers of dev_list expect the updates to it to take place from
within the opp_table->lock and this is missing in the case where the
dev_list is updated for already managed OPPs.

Fix that by calling _add_opp_dev() from there and remove the now unused
_add_opp_dev_unlocked() callback. While at it, also reduce the length of
the critical section in _add_opp_dev().

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>

diff --git a/drivers/opp/core.c b/drivers/opp/core.c
index 0e0a526..84035ab 100644 (file)
--- a/drivers/opp/core.c
+++ b/drivers/opp/core.c
@@ -1036,8 +1036,8 @@ static void _remove_opp_dev(struct opp_device *opp_dev,
        kfree(opp_dev);
 }
 
-static struct opp_device *_add_opp_dev_unlocked(const struct device *dev,
-                                               struct opp_table *opp_table)
+struct opp_device *_add_opp_dev(const struct device *dev,
+                               struct opp_table *opp_table)
 {
        struct opp_device *opp_dev;
 
@@ -1048,7 +1048,9 @@ static struct opp_device *_add_opp_dev_unlocked(const struct device *dev,
        /* Initialize opp-dev */
        opp_dev->dev = dev;
 
+       mutex_lock(&opp_table->lock);
        list_add(&opp_dev->node, &opp_table->dev_list);
+       mutex_unlock(&opp_table->lock);
 
        /* Create debugfs entries for the opp_table */
        opp_debug_register(opp_dev, opp_table);
@@ -1056,18 +1058,6 @@ static struct opp_device *_add_opp_dev_unlocked(const struct device *dev,
        return opp_dev;
 }
 
-struct opp_device *_add_opp_dev(const struct device *dev,
-                               struct opp_table *opp_table)
-{
-       struct opp_device *opp_dev;
-
-       mutex_lock(&opp_table->lock);
-       opp_dev = _add_opp_dev_unlocked(dev, opp_table);
-       mutex_unlock(&opp_table->lock);
-
-       return opp_dev;
-}
-
 static struct opp_table *_allocate_opp_table(struct device *dev, int index)
 {
        struct opp_table *opp_table;
@@ -1148,7 +1138,7 @@ static struct opp_table *_opp_get_opp_table(struct device *dev, int index)
 
        opp_table = _managed_opp(dev, index);
        if (opp_table) {
-               if (!_add_opp_dev_unlocked(dev, opp_table)) {
+               if (!_add_opp_dev(dev, opp_table)) {
                        dev_pm_opp_put_opp_table(opp_table);
                        opp_table = ERR_PTR(-ENOMEM);
                }