clk: Provide new devm_clk helpers for prepared and enabled clocks

[ Upstream commit 7ef9651e9792b08eb310c6beb202cbc947f43cab ]

When a driver keeps a clock prepared (or enabled) during the whole
lifetime of the driver, these helpers allow to simplify the drivers.

Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Alexandru Ardelean <aardelean@deviqon.com>
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/20220520075737.758761-4-u.kleine-koenig@pengutronix.de
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
Stable-dep-of: 340cb392a038 ("memory: atmel-sdramc: Fix missing clk_disable_unprepare in atmel_ramc_probe()")
Signed-off-by: Sasha Levin <sashal@kernel.org>

1 files changed, 109 insertions, 0 deletions

diff --git a/include/linux/clk.h b/include/linux/clk.h
index 7fd6a1febcf4..1814eabb7c20 100644
--- a/include/linux/clk.h
+++ b/include/linux/clk.h
@@ -419,6 +419,47 @@ int __must_check devm_clk_bulk_get_all(struct device *dev,
 struct clk *devm_clk_get(struct device *dev, const char *id);
 
 /**
+ * devm_clk_get_prepared - devm_clk_get() + clk_prepare()
+ * @dev: device for clock "consumer"
+ * @id: clock consumer ID
+ *
+ * Context: May sleep.
+ *
+ * Return: a struct clk corresponding to the clock producer, or
+ * valid IS_ERR() condition containing errno.  The implementation
+ * uses @dev and @id to determine the clock consumer, and thereby
+ * the clock producer.  (IOW, @id may be identical strings, but
+ * clk_get may return different clock producers depending on @dev.)
+ *
+ * The returned clk (if valid) is prepared. Drivers must however assume
+ * that the clock is not enabled.
+ *
+ * The clock will automatically be unprepared and freed when the device
+ * is unbound from the bus.
+ */
+struct clk *devm_clk_get_prepared(struct device *dev, const char *id);
+
+/**
+ * devm_clk_get_enabled - devm_clk_get() + clk_prepare_enable()
+ * @dev: device for clock "consumer"
+ * @id: clock consumer ID
+ *
+ * Context: May sleep.
+ *
+ * Return: a struct clk corresponding to the clock producer, or
+ * valid IS_ERR() condition containing errno.  The implementation
+ * uses @dev and @id to determine the clock consumer, and thereby
+ * the clock producer.  (IOW, @id may be identical strings, but
+ * clk_get may return different clock producers depending on @dev.)
+ *
+ * The returned clk (if valid) is prepared and enabled.
+ *
+ * The clock will automatically be disabled, unprepared and freed
+ * when the device is unbound from the bus.
+ */
+struct clk *devm_clk_get_enabled(struct device *dev, const char *id);
+
+/**
  * devm_clk_get_optional - lookup and obtain a managed reference to an optional
  *			   clock producer.
  * @dev: device for clock "consumer"
@@ -430,6 +471,50 @@ struct clk *devm_clk_get(struct device *dev, const char *id);
 struct clk *devm_clk_get_optional(struct device *dev, const char *id);
 
 /**
+ * devm_clk_get_optional_prepared - devm_clk_get_optional() + clk_prepare()
+ * @dev: device for clock "consumer"
+ * @id: clock consumer ID
+ *
+ * Context: May sleep.
+ *
+ * Return: a struct clk corresponding to the clock producer, or
+ * valid IS_ERR() condition containing errno.  The implementation
+ * uses @dev and @id to determine the clock consumer, and thereby
+ * the clock producer.  If no such clk is found, it returns NULL
+ * which serves as a dummy clk.  That's the only difference compared
+ * to devm_clk_get_prepared().
+ *
+ * The returned clk (if valid) is prepared. Drivers must however
+ * assume that the clock is not enabled.
+ *
+ * The clock will automatically be unprepared and freed when the
+ * device is unbound from the bus.
+ */
+struct clk *devm_clk_get_optional_prepared(struct device *dev, const char *id);
+
+/**
+ * devm_clk_get_optional_enabled - devm_clk_get_optional() +
+ *                                 clk_prepare_enable()
+ * @dev: device for clock "consumer"
+ * @id: clock consumer ID
+ *
+ * Context: May sleep.
+ *
+ * Return: a struct clk corresponding to the clock producer, or
+ * valid IS_ERR() condition containing errno.  The implementation
+ * uses @dev and @id to determine the clock consumer, and thereby
+ * the clock producer.  If no such clk is found, it returns NULL
+ * which serves as a dummy clk.  That's the only difference compared
+ * to devm_clk_get_enabled().
+ *
+ * The returned clk (if valid) is prepared and enabled.
+ *
+ * The clock will automatically be disabled, unprepared and freed
+ * when the device is unbound from the bus.
+ */
+struct clk *devm_clk_get_optional_enabled(struct device *dev, const char *id);
+
+/**
  * devm_get_clk_from_child - lookup and obtain a managed reference to a
  *			     clock producer from child node.
  * @dev: device for clock "consumer"
@@ -773,12 +858,36 @@ static inline struct clk *devm_clk_get(struct device *dev, const char *id)
 	return NULL;
 }
 
+static inline struct clk *devm_clk_get_prepared(struct device *dev,
+						const char *id)
+{
+	return NULL;
+}
+
+static inline struct clk *devm_clk_get_enabled(struct device *dev,
+					       const char *id)
+{
+	return NULL;
+}
+
 static inline struct clk *devm_clk_get_optional(struct device *dev,
 						const char *id)
 {
 	return NULL;
 }
 
+static inline struct clk *devm_clk_get_optional_prepared(struct device *dev,
+							 const char *id)
+{
+	return NULL;
+}
+
+static inline struct clk *devm_clk_get_optional_enabled(struct device *dev,
+							const char *id)
+{
+	return NULL;
+}
+
 static inline int __must_check devm_clk_bulk_get(struct device *dev, int num_clks,
 						 struct clk_bulk_data *clks)
 {