OPP: Introduce dev_pm_opp_find_freq_{ceil/floor}_indexed() APIs

In the case of devices with multiple clocks, drivers need to specify the
clock index for the OPP framework to find the OPP corresponding to the
floor/ceil of the supplied frequency. So let's introduce the two new APIs
accepting the clock index as an argument.

These APIs use the exising _find_key_ceil() helper by supplying the clock
index to it.

Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
[ Viresh: Rearranged definitions in pm_opp.h ]
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>

Author: Mani-Sadhasivam

drivers/opp/core.c

@@ -658,6 +658,34 @@ struct dev_pm_opp *dev_pm_opp_find_freq_ceil(struct device *dev,
 }
 EXPORT_SYMBOL_GPL(dev_pm_opp_find_freq_ceil);
 
+/**
+ * dev_pm_opp_find_freq_ceil_indexed() - Search for a rounded ceil freq for the
+ *					 clock corresponding to the index
+ * @dev:	Device for which we do this operation
+ * @freq:	Start frequency
+ * @index:	Clock index
+ *
+ * Search for the matching ceil *available* OPP for the clock corresponding to
+ * the specified index from a starting freq for a device.
+ *
+ * Return: matching *opp and refreshes *freq accordingly, else returns
+ * ERR_PTR in case of error and should be handled using IS_ERR. Error return
+ * values can be:
+ * EINVAL:	for bad pointer
+ * ERANGE:	no match found for search
+ * ENODEV:	if device not found in list of registered devices
+ *
+ * The callers are required to call dev_pm_opp_put() for the returned OPP after
+ * use.
+ */
+struct dev_pm_opp *
+dev_pm_opp_find_freq_ceil_indexed(struct device *dev, unsigned long *freq,
+				  u32 index)
+{
+	return _find_key_ceil(dev, freq, index, true, _read_freq, NULL);
+}
+EXPORT_SYMBOL_GPL(dev_pm_opp_find_freq_ceil_indexed);
+
 /**
  * dev_pm_opp_find_freq_floor() - Search for a rounded floor freq
  * @dev:	device for which we do this operation
@@ -683,6 +711,34 @@ struct dev_pm_opp *dev_pm_opp_find_freq_floor(struct device *dev,
 }
 EXPORT_SYMBOL_GPL(dev_pm_opp_find_freq_floor);
 
+/**
+ * dev_pm_opp_find_freq_floor_indexed() - Search for a rounded floor freq for the
+ *					  clock corresponding to the index
+ * @dev:	Device for which we do this operation
+ * @freq:	Start frequency
+ * @index:	Clock index
+ *
+ * Search for the matching floor *available* OPP for the clock corresponding to
+ * the specified index from a starting freq for a device.
+ *
+ * Return: matching *opp and refreshes *freq accordingly, else returns
+ * ERR_PTR in case of error and should be handled using IS_ERR. Error return
+ * values can be:
+ * EINVAL:	for bad pointer
+ * ERANGE:	no match found for search
+ * ENODEV:	if device not found in list of registered devices
+ *
+ * The callers are required to call dev_pm_opp_put() for the returned OPP after
+ * use.
+ */
+struct dev_pm_opp *
+dev_pm_opp_find_freq_floor_indexed(struct device *dev, unsigned long *freq,
+				   u32 index)
+{
+	return _find_key_floor(dev, freq, index, true, _read_freq, NULL);
+}
+EXPORT_SYMBOL_GPL(dev_pm_opp_find_freq_floor_indexed);
+
 /**
  * dev_pm_opp_find_level_exact() - search for an exact level
  * @dev:		device for which we do this operation

include/linux/pm_opp.h

@@ -125,9 +125,15 @@ struct dev_pm_opp *dev_pm_opp_find_freq_exact(struct device *dev,
 struct dev_pm_opp *dev_pm_opp_find_freq_floor(struct device *dev,
 					      unsigned long *freq);
 
+struct dev_pm_opp *dev_pm_opp_find_freq_floor_indexed(struct device *dev,
+						      unsigned long *freq, u32 index);
+
 struct dev_pm_opp *dev_pm_opp_find_freq_ceil(struct device *dev,
 					     unsigned long *freq);
 
+struct dev_pm_opp *dev_pm_opp_find_freq_ceil_indexed(struct device *dev,
+						     unsigned long *freq, u32 index);
+
 struct dev_pm_opp *dev_pm_opp_find_level_exact(struct device *dev,
 					       unsigned int level);
 
@@ -261,12 +267,24 @@ static inline struct dev_pm_opp *dev_pm_opp_find_freq_floor(struct device *dev,
 	return ERR_PTR(-EOPNOTSUPP);
 }
 
+static inline struct dev_pm_opp *
+dev_pm_opp_find_freq_floor_indexed(struct device *dev, unsigned long *freq, u32 index)
+{
+	return ERR_PTR(-EOPNOTSUPP);
+}
+
 static inline struct dev_pm_opp *dev_pm_opp_find_freq_ceil(struct device *dev,
 					unsigned long *freq)
 {
 	return ERR_PTR(-EOPNOTSUPP);
 }
 
+static inline struct dev_pm_opp *
+dev_pm_opp_find_freq_ceil_indexed(struct device *dev, unsigned long *freq, u32 index)
+{
+	return ERR_PTR(-EOPNOTSUPP);
+}
+
 static inline struct dev_pm_opp *dev_pm_opp_find_level_exact(struct device *dev,
 					unsigned int level)
 {