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

From: Sibi Sankar <sibis@codeaurora.org>
To: viresh.kumar@linaro.org, sboyd@kernel.org,
	georgi.djakov@linaro.org, saravanak@google.com
Cc: nm@ti.com, bjorn.andersson@linaro.org, agross@kernel.org,
	david.brown@linaro.org, robh+dt@kernel.org, mark.rutland@arm.com,
	rjw@rjwysocki.net, linux-arm-msm@vger.kernel.org,
	devicetree@vger.kernel.org, linux-kernel@vger.kernel.org,
	linux-pm@vger.kernel.org, dianders@chromium.org,
	mka@chromium.org, vincent.guittot@linaro.org,
	amit.kucheria@linaro.org, ulf.hansson@linaro.org,
	Sibi Sankar <sibis@codeaurora.org>
Subject: [RFC v3 06/10] opp: Allow multiple opp_tables to be mapped to a single device
Date: Tue, 28 Jan 2020 01:33:46 +0530	[thread overview]
Message-ID: <20200127200350.24465-7-sibis@codeaurora.org> (raw)
In-Reply-To: <20200127200350.24465-1-sibis@codeaurora.org>

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@codeaurora.org>
---
 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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