[PATCH] regulator: Add devm_regulator_get()

[PATCH] regulator: Add devm_regulator_get()

[Stephen Boyd]

Add a resource managed regulator_get() to simplify regulator
usage in drivers. This allows driver authors to "get and forget"
about their regulators by automatically calling regulator_put()
when the driver is detached.

Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
---
 Documentation/driver-model/devres.txt |    3 +++
 drivers/regulator/core.c              |   33 +++++++++++++++++++++++++++++++++
 include/linux/regulator/consumer.h    |    7 +++++++
 3 files changed, 43 insertions(+), 0 deletions(-)

diff --git a/Documentation/driver-model/devres.txt b/Documentation/driver-model/devres.txt
index 10c64c8..016fd2b 100644
--- a/Documentation/driver-model/devres.txt
+++ b/Documentation/driver-model/devres.txt
@@ -267,3 +267,6 @@ IOMAP
   pcim_iounmap()
   pcim_iomap_table()	: array of mapped addresses indexed by BAR
   pcim_iomap_regions()	: do request_region() and iomap() on multiple BARs
+
+REGULATOR
+  devm_regulator_get()
diff --git a/drivers/regulator/core.c b/drivers/regulator/core.c
index ca86f39..b05b058 100644
--- a/drivers/regulator/core.c
+++ b/drivers/regulator/core.c
@@ -1320,6 +1320,39 @@ struct regulator *regulator_get(struct device *dev, const char *id)
 }
 EXPORT_SYMBOL_GPL(regulator_get);
 
+static void devm_regulator_release(struct device *dev, void *res)
+{
+	regulator_put(*(struct regulator **)res);
+}
+
+/**
+ * devm_regulator_get - Resource managed regulator_get()
+ * @dev: device for regulator "consumer"
+ * @id: Supply name or regulator ID.
+ *
+ * Managed regulator_get(). Regulators returned from this function are
+ * automatically regulator_put() on driver detach. See regulator_get() for more
+ * information.
+ */
+struct regulator *devm_regulator_get(struct device *dev, const char *id)
+{
+	struct regulator **ptr, *regulator;
+
+	ptr = devres_alloc(devm_regulator_release, sizeof(*ptr), GFP_KERNEL);
+	if (!ptr)
+		return ERR_PTR(-ENOMEM);
+
+	regulator = regulator_get(dev, id);
+	if (!IS_ERR(regulator)) {
+		*ptr = regulator;
+		devres_add(dev, ptr);
+	} else
+		devres_free(ptr);
+
+	return regulator;
+}
+EXPORT_SYMBOL_GPL(devm_regulator_get);
+
 /**
  * regulator_get_exclusive - obtain exclusive access to a regulator.
  * @dev: device for regulator "consumer"
diff --git a/include/linux/regulator/consumer.h b/include/linux/regulator/consumer.h
index f2698a0..bbe45b0 100644
--- a/include/linux/regulator/consumer.h
+++ b/include/linux/regulator/consumer.h
@@ -132,6 +132,8 @@ struct regulator_bulk_data {
 /* regulator get and put */
 struct regulator *__must_check regulator_get(struct device *dev,
 					     const char *id);
+struct regulator *__must_check devm_regulator_get(struct device *dev,
+					     const char *id);
 struct regulator *__must_check regulator_get_exclusive(struct device *dev,
 						       const char *id);
 void regulator_put(struct regulator *regulator);
@@ -200,6 +202,11 @@ static inline struct regulator *__must_check regulator_get(struct device *dev,
 	 */
 	return NULL;
 }
+static inline struct regulator *__must_check
+devm_regulator_get(struct device *dev, const char *id)
+{
+	return NULL;
+}
 static inline void regulator_put(struct regulator *regulator)
 {
 }
-- 
Sent by an employee of the Qualcomm Innovation Center, Inc.
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum.

Re: [PATCH] regulator: Add devm_regulator_get()

[Mark Brown]

On Mon, Jan 16, 2012 at 07:39:58PM -0800, Stephen Boyd wrote:
> Add a resource managed regulator_get() to simplify regulator
> usage in drivers. This allows driver authors to "get and forget"
> about their regulators by automatically calling regulator_put()
> when the driver is detached.

So, I've gone ahead and applied this as it's obviously useful as-is but
it's obviously something that should have a bulk version - I'll probably
add that myself.  We really ought to have release functions too in case
something wants to release the resource earlier, though I can't think
where you'd actually use those.

Re: [PATCH] regulator: Add devm_regulator_get()

[Mark Brown]

On Mon, Jan 16, 2012 at 07:39:58PM -0800, Stephen Boyd wrote:

> @@ -200,6 +202,11 @@ static inline struct regulator *__must_check regulator_get(struct device *dev,
>  	 */
>  	return NULL;
>  }
> +static inline struct regulator *__must_check
> +devm_regulator_get(struct device *dev, const char *id)
> +{
> +	return NULL;
> +}
>  static inline void regulator_put(struct regulator *regulator)
>  {
>  }

Oh, and it's not obvious from the diff but blank lines please like the
adjacent code.

Re: [PATCH] regulator: Add devm_regulator_get()

[Stephen Boyd]

On 01/17/12 03:04, Mark Brown wrote:
> On Mon, Jan 16, 2012 at 07:39:58PM -0800, Stephen Boyd wrote:
>
>> @@ -200,6 +202,11 @@ static inline struct regulator *__must_check regulator_get(struct device *dev,
>>  	 */
>>  	return NULL;
>>  }
>> +static inline struct regulator *__must_check
>> +devm_regulator_get(struct device *dev, const char *id)
>> +{
>> +	return NULL;
>> +}
>>  static inline void regulator_put(struct regulator *regulator)
>>  {
>>  }
> Oh, and it's not obvious from the diff but blank lines please like the
> adjacent code.

Should I resend or are you ok with adding the newline there yourself?

-- 
Sent by an employee of the Qualcomm Innovation Center, Inc.
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum.

Re: [PATCH] regulator: Add devm_regulator_get()

[Mark Brown]

On Tue, Jan 17, 2012 at 08:54:40AM -0800, Stephen Boyd wrote:
> On 01/17/12 03:04, Mark Brown wrote:

> > Oh, and it's not obvious from the diff but blank lines please like the
> > adjacent code.

> Should I resend or are you ok with adding the newline there yourself?

I fixed that and also added some missing braces.