[RFC v3 06/10] opp: Allow multiple opp_tables to be mapped to a single device

From: Sibi Sankar
Date: Mon Jan 27 2020 - 15:05:02 EST


Introduce _find_opp_table_indexed and its unlocked variant to allow for
multiple distinct opp_tables to be linked to a single device.

Signed-off-by: Sibi Sankar <sibis@xxxxxxxxxxxxxx>
---
drivers/opp/core.c | 41 +++++++++++++++++++++++++++++++++--------
1 file changed, 33 insertions(+), 8 deletions(-)

diff --git a/drivers/opp/core.c b/drivers/opp/core.c
index f241e83ec926a..e9d633c9e40b1 100644
--- a/drivers/opp/core.c
+++ b/drivers/opp/core.c
@@ -46,19 +46,26 @@ static struct opp_device *_find_opp_dev(const struct device *dev,
return NULL;
}

-static struct opp_table *_find_opp_table_unlocked(struct device *dev)
+static struct opp_table *_find_opp_table_indexed_unlocked(struct device *dev,
+ int index)
{
struct opp_table *opp_table;
+ struct device_node *np;
bool found;

+ np = _opp_of_get_opp_desc_node(dev->of_node, index);
+ of_node_put(np);
+
list_for_each_entry(opp_table, &opp_tables, node) {
mutex_lock(&opp_table->lock);
found = !!_find_opp_dev(dev, opp_table);
mutex_unlock(&opp_table->lock);

if (found) {
- _get_opp_table_kref(opp_table);
+ if (np && opp_table->np != np)
+ continue;

+ _get_opp_table_kref(opp_table);
return opp_table;
}
}
@@ -67,17 +74,19 @@ static struct opp_table *_find_opp_table_unlocked(struct device *dev)
}

/**
- * _find_opp_table() - find opp_table struct using device pointer
+ * _find_opp_table_indexed() - find opp_table struct using device pointer
* @dev: device pointer used to lookup OPP table
+ * @index: Index number.
*
- * Search OPP table for one containing matching device.
+ * Search OPP table for one containing matching device at the given
+ * index.
*
* Return: pointer to 'struct opp_table' if found, otherwise -ENODEV or
* -EINVAL based on type of error.
*
* The callers must call dev_pm_opp_put_opp_table() after the table is used.
*/
-struct opp_table *_find_opp_table(struct device *dev)
+struct opp_table *_find_opp_table_indexed(struct device *dev, int index)
{
struct opp_table *opp_table;

@@ -87,12 +96,28 @@ struct opp_table *_find_opp_table(struct device *dev)
}

mutex_lock(&opp_table_lock);
- opp_table = _find_opp_table_unlocked(dev);
+ opp_table = _find_opp_table_indexed_unlocked(dev, index);
mutex_unlock(&opp_table_lock);

return opp_table;
}

+/**
+ * _find_opp_table() - find opp_table struct using device pointer
+ * @dev: device pointer used to lookup OPP table
+ *
+ * Search OPP table for one containing matching device.
+ *
+ * Return: pointer to 'struct opp_table' if found, otherwise -ENODEV or
+ * -EINVAL based on type of error.
+ *
+ * The callers must call dev_pm_opp_put_opp_table() after the table is used.
+ */
+struct opp_table *_find_opp_table(struct device *dev)
+{
+ return _find_opp_table_indexed(dev, 0);
+}
+
/**
* dev_pm_opp_get_voltage() - Gets the voltage corresponding to an opp
* @opp: opp for which voltage has to be returned for
@@ -1238,7 +1263,7 @@ static struct opp_table *_opp_get_opp_table(struct device *dev, int index)
/* Hold our table modification lock here */
mutex_lock(&opp_table_lock);

- opp_table = _find_opp_table_unlocked(dev);
+ opp_table = _find_opp_table_indexed_unlocked(dev, index);
if (!IS_ERR(opp_table))
goto unlock;

@@ -2612,7 +2637,7 @@ void _dev_pm_opp_find_and_remove_table(struct device *dev)
struct opp_table *opp_table;

/* Check for existing table for 'dev' */
- opp_table = _find_opp_table(dev);
+ opp_table = _find_opp_table_indexed(dev, 0);
if (IS_ERR(opp_table)) {
int error = PTR_ERR(opp_table);

--
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