OPP: Initialize scope-based pointers inline

Uninitialized pointers with `__free` attribute can cause undefined
behaviour as the memory allocated to the pointer is freed automatically
when the pointer goes out of scope.

The OPP core doesn't have any bugs related to this as of now, but it is
better to initialize pointers marked with `__free` attribute at
declaration to simplify the code and ensure proper scope-based cleanup.

Reported-by: Joe Perches <joe@perches.com>
Reported-by: Dan Carpenter <dan.carpenter@linaro.org>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>

1 files changed, 38 insertions, 31 deletions

diff --git a/drivers/opp/core.c b/drivers/opp/core.c
index bba4f7daff8c..dbebb8c829bc 100644
--- a/drivers/opp/core.c
+++ b/drivers/opp/core.c
@@ -309,9 +309,9 @@ EXPORT_SYMBOL_GPL(dev_pm_opp_is_turbo);
  */
 unsigned long dev_pm_opp_get_max_clock_latency(struct device *dev)
 {
-	struct opp_table *opp_table __free(put_opp_table);
+	struct opp_table *opp_table __free(put_opp_table) =
+		_find_opp_table(dev);
 
-	opp_table = _find_opp_table(dev);
 	if (IS_ERR(opp_table))
 		return 0;
 
@@ -327,7 +327,6 @@ EXPORT_SYMBOL_GPL(dev_pm_opp_get_max_clock_latency);
  */
 unsigned long dev_pm_opp_get_max_volt_latency(struct device *dev)
 {
-	struct opp_table *opp_table __free(put_opp_table);
 	struct dev_pm_opp *opp;
 	struct regulator *reg;
 	unsigned long latency_ns = 0;
@@ -337,7 +336,9 @@ unsigned long dev_pm_opp_get_max_volt_latency(struct device *dev)
 		unsigned long max;
 	} *uV;
 
-	opp_table = _find_opp_table(dev);
+	struct opp_table *opp_table __free(put_opp_table) =
+		_find_opp_table(dev);
+
 	if (IS_ERR(opp_table))
 		return 0;
 
@@ -409,10 +410,11 @@ EXPORT_SYMBOL_GPL(dev_pm_opp_get_max_transition_latency);
  */
 unsigned long dev_pm_opp_get_suspend_opp_freq(struct device *dev)
 {
-	struct opp_table *opp_table __free(put_opp_table);
 	unsigned long freq = 0;
 
-	opp_table = _find_opp_table(dev);
+	struct opp_table *opp_table __free(put_opp_table) =
+		_find_opp_table(dev);
+
 	if (IS_ERR(opp_table))
 		return 0;
 
@@ -447,9 +449,9 @@ int _get_opp_count(struct opp_table *opp_table)
  */
 int dev_pm_opp_get_opp_count(struct device *dev)
 {
-	struct opp_table *opp_table __free(put_opp_table);
+	struct opp_table *opp_table __free(put_opp_table) =
+		_find_opp_table(dev);
 
-	opp_table = _find_opp_table(dev);
 	if (IS_ERR(opp_table)) {
 		dev_dbg(dev, "%s: OPP table not found (%ld)\n",
 			__func__, PTR_ERR(opp_table));
@@ -605,9 +607,9 @@ _find_key(struct device *dev, unsigned long *key, int index, bool available,
 			  unsigned long opp_key, unsigned long key),
 	  bool (*assert)(struct opp_table *opp_table, unsigned int index))
 {
-	struct opp_table *opp_table __free(put_opp_table);
+	struct opp_table *opp_table __free(put_opp_table) =
+		_find_opp_table(dev);
 
-	opp_table = _find_opp_table(dev);
 	if (IS_ERR(opp_table)) {
 		dev_err(dev, "%s: OPP table not found (%ld)\n", __func__,
 			PTR_ERR(opp_table));
@@ -1410,12 +1412,13 @@ static int _set_opp(struct device *dev, struct opp_table *opp_table,
  */
 int dev_pm_opp_set_rate(struct device *dev, unsigned long target_freq)
 {
-	struct opp_table *opp_table __free(put_opp_table);
 	struct dev_pm_opp *opp __free(put_opp) = NULL;
 	unsigned long freq = 0, temp_freq;
 	bool forced = false;
 
-	opp_table = _find_opp_table(dev);
+	struct opp_table *opp_table __free(put_opp_table) =
+		_find_opp_table(dev);
+
 	if (IS_ERR(opp_table)) {
 		dev_err(dev, "%s: device's opp table doesn't exist\n", __func__);
 		return PTR_ERR(opp_table);
@@ -1477,9 +1480,9 @@ EXPORT_SYMBOL_GPL(dev_pm_opp_set_rate);
  */
 int dev_pm_opp_set_opp(struct device *dev, struct dev_pm_opp *opp)
 {
-	struct opp_table *opp_table __free(put_opp_table);
+	struct opp_table *opp_table __free(put_opp_table) =
+		_find_opp_table(dev);
 
-	opp_table = _find_opp_table(dev);
 	if (IS_ERR(opp_table)) {
 		dev_err(dev, "%s: device opp doesn't exist\n", __func__);
 		return PTR_ERR(opp_table);
@@ -1794,10 +1797,11 @@ EXPORT_SYMBOL_GPL(dev_pm_opp_put);
  */
 void dev_pm_opp_remove(struct device *dev, unsigned long freq)
 {
-	struct opp_table *opp_table __free(put_opp_table);
 	struct dev_pm_opp *opp = NULL, *iter;
 
-	opp_table = _find_opp_table(dev);
+	struct opp_table *opp_table __free(put_opp_table) =
+		_find_opp_table(dev);
+
 	if (IS_ERR(opp_table))
 		return;
 
@@ -1885,9 +1889,9 @@ bool _opp_remove_all_static(struct opp_table *opp_table)
  */
 void dev_pm_opp_remove_all_dynamic(struct device *dev)
 {
-	struct opp_table *opp_table __free(put_opp_table);
+	struct opp_table *opp_table __free(put_opp_table) =
+		_find_opp_table(dev);
 
-	opp_table = _find_opp_table(dev);
 	if (IS_ERR(opp_table))
 		return;
 
@@ -2871,10 +2875,11 @@ static int _opp_set_availability(struct device *dev, unsigned long freq,
 				 bool availability_req)
 {
 	struct dev_pm_opp *opp __free(put_opp) = ERR_PTR(-ENODEV), *tmp_opp;
-	struct opp_table *opp_table __free(put_opp_table);
 
 	/* Find the opp_table */
-	opp_table = _find_opp_table(dev);
+	struct opp_table *opp_table __free(put_opp_table) =
+		_find_opp_table(dev);
+
 	if (IS_ERR(opp_table)) {
 		dev_warn(dev, "%s: Device OPP not found (%ld)\n", __func__,
 			 PTR_ERR(opp_table));
@@ -2932,11 +2937,12 @@ int dev_pm_opp_adjust_voltage(struct device *dev, unsigned long freq,
 
 {
 	struct dev_pm_opp *opp __free(put_opp) = ERR_PTR(-ENODEV), *tmp_opp;
-	struct opp_table *opp_table __free(put_opp_table);
 	int r;
 
 	/* Find the opp_table */
-	opp_table = _find_opp_table(dev);
+	struct opp_table *opp_table __free(put_opp_table) =
+		_find_opp_table(dev);
+
 	if (IS_ERR(opp_table)) {
 		r = PTR_ERR(opp_table);
 		dev_warn(dev, "%s: Device OPP not found (%d)\n", __func__, r);
@@ -2986,12 +2992,13 @@ EXPORT_SYMBOL_GPL(dev_pm_opp_adjust_voltage);
  */
 int dev_pm_opp_sync_regulators(struct device *dev)
 {
-	struct opp_table *opp_table __free(put_opp_table);
 	struct regulator *reg;
 	int ret, i;
 
 	/* Device may not have OPP table */
-	opp_table = _find_opp_table(dev);
+	struct opp_table *opp_table __free(put_opp_table) =
+		_find_opp_table(dev);
+
 	if (IS_ERR(opp_table))
 		return 0;
 
@@ -3062,9 +3069,9 @@ EXPORT_SYMBOL_GPL(dev_pm_opp_disable);
  */
 int dev_pm_opp_register_notifier(struct device *dev, struct notifier_block *nb)
 {
-	struct opp_table *opp_table __free(put_opp_table);
+	struct opp_table *opp_table __free(put_opp_table) =
+		_find_opp_table(dev);
 
-	opp_table = _find_opp_table(dev);
 	if (IS_ERR(opp_table))
 		return PTR_ERR(opp_table);
 
@@ -3082,9 +3089,9 @@ EXPORT_SYMBOL(dev_pm_opp_register_notifier);
 int dev_pm_opp_unregister_notifier(struct device *dev,
 				   struct notifier_block *nb)
 {
-	struct opp_table *opp_table __free(put_opp_table);
+	struct opp_table *opp_table __free(put_opp_table) =
+		_find_opp_table(dev);
 
-	opp_table = _find_opp_table(dev);
 	if (IS_ERR(opp_table))
 		return PTR_ERR(opp_table);
 
@@ -3101,10 +3108,10 @@ EXPORT_SYMBOL(dev_pm_opp_unregister_notifier);
  */
 void dev_pm_opp_remove_table(struct device *dev)
 {
-	struct opp_table *opp_table __free(put_opp_table);
-
 	/* Check for existing table for 'dev' */
-	opp_table = _find_opp_table(dev);
+	struct opp_table *opp_table __free(put_opp_table) =
+		_find_opp_table(dev);
+
 	if (IS_ERR(opp_table)) {
 		int error = PTR_ERR(opp_table);