OPP: Add and export helper to set bandwidth

Add and export 'dev_pm_opp_set_bw' to set the bandwidth
levels associated with an OPP.
Signed-off-by: Sibi Sankar <sibis@codeaurora.org>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>

drivers/opp/core.c

@@ -831,6 +831,37 @@ static int _set_required_opps(struct device *dev,
 	return ret;
 }
 
+/**
+ * dev_pm_opp_set_bw() - sets bandwidth levels corresponding to an opp
+ * @dev:	device for which we do this operation
+ * @opp:	opp based on which the bandwidth levels are to be configured
+ *
+ * This configures the bandwidth to the levels specified by the OPP. However
+ * if the OPP specified is NULL the bandwidth levels are cleared out.
+ *
+ * Return: 0 on success or a negative error value.
+ */
+int dev_pm_opp_set_bw(struct device *dev, struct dev_pm_opp *opp)
+{
+	struct opp_table *opp_table;
+	int ret;
+
+	opp_table = _find_opp_table(dev);
+	if (IS_ERR(opp_table)) {
+		dev_err(dev, "%s: device opp table doesn't exist\n", __func__);
+		return PTR_ERR(opp_table);
+	}
+
+	if (opp)
+		ret = _set_opp_bw(opp_table, opp, dev, false);
+	else
+		ret = _set_opp_bw(opp_table, NULL, dev, true);
+
+	dev_pm_opp_put_opp_table(opp_table);
+	return ret;
+}
+EXPORT_SYMBOL_GPL(dev_pm_opp_set_bw);
+
 /**
  * dev_pm_opp_set_rate() - Configure new OPP based on frequency
  * @dev:	 device for which we do this operation

include/linux/pm_opp.h

@@ -151,6 +151,7 @@ struct opp_table *dev_pm_opp_attach_genpd(struct device *dev, const char **names
 void dev_pm_opp_detach_genpd(struct opp_table *opp_table);
 int dev_pm_opp_xlate_performance_state(struct opp_table *src_table, struct opp_table *dst_table, unsigned int pstate);
 int dev_pm_opp_set_rate(struct device *dev, unsigned long target_freq);
+int dev_pm_opp_set_bw(struct device *dev, struct dev_pm_opp *opp);
 int dev_pm_opp_set_sharing_cpus(struct device *cpu_dev, const struct cpumask *cpumask);
 int dev_pm_opp_get_sharing_cpus(struct device *cpu_dev, struct cpumask *cpumask);
 void dev_pm_opp_remove_table(struct device *dev);
@@ -342,6 +343,11 @@ static inline int dev_pm_opp_set_rate(struct device *dev, unsigned long target_f
 	return -ENOTSUPP;
 }
 
+static inline int dev_pm_opp_set_bw(struct device *dev, struct dev_pm_opp *opp)
+{
+	return -EOPNOTSUPP;
+}
+
 static inline int dev_pm_opp_set_sharing_cpus(struct device *cpu_dev, const struct cpumask *cpumask)
 {
 	return -ENOTSUPP;