opp: Make _set_opp_custom() work without regulators

Check whether OPP table has regulators in _set_opp_custom() and set up
dev_pm_set_opp_data accordingly. Now _set_opp_custom() works properly,
i.e. it doesn't crash if OPP table doesn't have assigned regulators.
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
[ Viresh: Rearrange the routine a bit ]
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>

drivers/opp/core.c

@@ -828,24 +828,31 @@ static int _set_opp_custom(const struct opp_table *opp_table,
 			   struct dev_pm_opp_supply *old_supply,
 			   struct dev_pm_opp_supply *new_supply)
 {
-	struct dev_pm_set_opp_data *data;
+	struct dev_pm_set_opp_data *data = opp_table->set_opp_data;
 	int size;
 
-	data = opp_table->set_opp_data;
+	/*
+	 * We support this only if dev_pm_opp_set_regulators() was called
+	 * earlier.
+	 */
+	if (opp_table->sod_supplies) {
+		size = sizeof(*old_supply) * opp_table->regulator_count;
+		if (!old_supply)
+			memset(data->old_opp.supplies, 0, size);
+		else
+			memcpy(data->old_opp.supplies, old_supply, size);
+
+		memcpy(data->new_opp.supplies, new_supply, size);
+		data->regulator_count = opp_table->regulator_count;
+	} else {
+		data->regulator_count = 0;
+	}
+
 	data->regulators = opp_table->regulators;
-	data->regulator_count = opp_table->regulator_count;
 	data->clk = opp_table->clk;
 	data->dev = dev;
-
 	data->old_opp.rate = old_freq;
-	size = sizeof(*old_supply) * opp_table->regulator_count;
-	if (!old_supply)
-		memset(data->old_opp.supplies, 0, size);
-	else
-		memcpy(data->old_opp.supplies, old_supply, size);
-
 	data->new_opp.rate = freq;
-	memcpy(data->new_opp.supplies, new_supply, size);
 
 	return opp_table->set_opp(data);
 }