diff mbox series

[1/5] iio: buffer-dmaengine: add dev-managed calls for buffer alloc/free

Message ID 20200220150317.1864-1-alexandru.ardelean@analog.com (mailing list archive)
State New, archived
Headers show
Series [1/5] iio: buffer-dmaengine: add dev-managed calls for buffer alloc/free | expand

Commit Message

Alexandru Ardelean Feb. 20, 2020, 3:03 p.m. UTC 
Currently, when using a 'iio_dmaengine_buffer_alloc()', an matching call to
'iio_dmaengine_buffer_free()' must be made.

With this change, this can be avoided by using
'devm_iio_dmaengine_buffer_alloc()'. The buffer will get free'd via the
device's devres handling.

Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com>
---
 .../buffer/industrialio-buffer-dmaengine.c    | 70 +++++++++++++++++++
 include/linux/iio/buffer-dmaengine.h          |  5 ++
 2 files changed, 75 insertions(+)

Comments

Jonathan Cameron Feb. 21, 2020, 12:21 p.m. UTC | #1 
On Thu, 20 Feb 2020 17:03:13 +0200
Alexandru Ardelean <alexandru.ardelean@analog.com> wrote:

> Currently, when using a 'iio_dmaengine_buffer_alloc()', an matching call to
> 'iio_dmaengine_buffer_free()' must be made.
> 
> With this change, this can be avoided by using
> 'devm_iio_dmaengine_buffer_alloc()'. The buffer will get free'd via the
> device's devres handling.
> 
> Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com>
> ---
>  .../buffer/industrialio-buffer-dmaengine.c    | 70 +++++++++++++++++++
>  include/linux/iio/buffer-dmaengine.h          |  5 ++
>  2 files changed, 75 insertions(+)
> 
> diff --git a/drivers/iio/buffer/industrialio-buffer-dmaengine.c b/drivers/iio/buffer/industrialio-buffer-dmaengine.c
> index b129693af0fd..eff89037e3f5 100644
> --- a/drivers/iio/buffer/industrialio-buffer-dmaengine.c
> +++ b/drivers/iio/buffer/industrialio-buffer-dmaengine.c
> @@ -229,6 +229,76 @@ void iio_dmaengine_buffer_free(struct iio_buffer *buffer)
>  }
>  EXPORT_SYMBOL_GPL(iio_dmaengine_buffer_free);
>  
> +static void __devm_iio_dmaengine_buffer_free(struct device *dev, void *res)
> +{
> +	iio_dmaengine_buffer_free(*(struct iio_buffer **)res);
> +}
> +
> +/**
> + * devm_iio_dmaengine_buffer_alloc() - Resource-managed iio_dmaengine_buffer_alloc()
> + * @dev: Parent device for the buffer
> + * @channel: DMA channel name, typically "rx".
> + *
> + * This allocates a new IIO buffer which internally uses the DMAengine framework
> + * to perform its transfers. The parent device will be used to request the DMA
> + * channel.
> + *
> + * Once done using the buffer iio_dmaengine_buffer_free() should be used to
> + * release it.

Umm.  It really shouldn't!

> + */
> +struct iio_buffer *devm_iio_dmaengine_buffer_alloc(struct device *dev,
> +	const char *channel)
> +{
> +	struct iio_buffer **bufferp, *buffer;
> +
> +	bufferp = devres_alloc(__devm_iio_dmaengine_buffer_free,
> +			       sizeof(*bufferp), GFP_KERNEL);
> +	if (!bufferp)
> +		return ERR_PTR(-ENOMEM);
> +
> +	buffer = iio_dmaengine_buffer_alloc(dev, channel);
> +	if (!IS_ERR(buffer)) {
> +		*bufferp = buffer;
> +		devres_add(dev, bufferp);

From a flow point of view I'd prefer.

	if (IS_ERR(buffer) {
		devres_free(buferp)
		return buffer;
	}

	*bufferp = buffer;
	devres_add(dev, bufferp);

	return buffer;


> +	} else {
> +		devres_free(bufferp);
> +	}
> +
> +	return buffer;
> +}
> +EXPORT_SYMBOL_GPL(devm_iio_dmaengine_buffer_alloc);
> +
> +static int devm_iio_dmaengine_buffer_match(struct device *dev, void *res,
> +	void *data)
> +{
> +	struct iio_buffer **r = res;
> +
> +	if (!r || !*r) {
> +		WARN_ON(!r || !*r);
> +		return 0;
> +	}
> +
> +	return *r == data;
> +}
> +
> +/**
> + * devm_iio_dmaengine_buffer_free - iio_dmaengine_buffer_free
> + * @dev: Device this iio_buffer belongs to
> + * @buffer: The iio_buffer associated with the device
> + *
> + * Free buffer allocated with devm_iio_dmaengine_buffer_alloc().
> + */
> +void devm_iio_dmaengine_buffer_free(struct device *dev,
> +	struct iio_buffer *buffer)
> +{
> +	int rc;
> +
> +	rc = devres_release(dev, __devm_iio_dmaengine_buffer_free,
> +			    devm_iio_dmaengine_buffer_match, buffer);
> +	WARN_ON(rc);
> +}
> +EXPORT_SYMBOL_GPL(devm_iio_dmaengine_buffer_free);
> +
>  MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>");
>  MODULE_DESCRIPTION("DMA buffer for the IIO framework");
>  MODULE_LICENSE("GPL");
> diff --git a/include/linux/iio/buffer-dmaengine.h b/include/linux/iio/buffer-dmaengine.h
> index b3a57444a886..8dcd973d76c1 100644
> --- a/include/linux/iio/buffer-dmaengine.h
> +++ b/include/linux/iio/buffer-dmaengine.h
> @@ -14,4 +14,9 @@ struct iio_buffer *iio_dmaengine_buffer_alloc(struct device *dev,
>  	const char *channel);
>  void iio_dmaengine_buffer_free(struct iio_buffer *buffer);
>  
> +struct iio_buffer *devm_iio_dmaengine_buffer_alloc(struct device *dev,
> +	const char *channel);
> +void devm_iio_dmaengine_buffer_free(struct device *dev,
> +	struct iio_buffer *buffer);
Please align parameters with opening bracket where possible.

Thanks,

Jonathan

> +
>  #endif
Alexandru Ardelean Feb. 25, 2020, 1:33 p.m. UTC | #2 
On Fri, 2020-02-21 at 12:21 +0000, Jonathan Cameron wrote:
> [External]
> 
> On Thu, 20 Feb 2020 17:03:13 +0200
> Alexandru Ardelean <alexandru.ardelean@analog.com> wrote:
> 
> > Currently, when using a 'iio_dmaengine_buffer_alloc()', an matching call to
> > 'iio_dmaengine_buffer_free()' must be made.
> > 
> > With this change, this can be avoided by using
> > 'devm_iio_dmaengine_buffer_alloc()'. The buffer will get free'd via the
> > device's devres handling.
> > 
> > Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com>
> > ---
> >  .../buffer/industrialio-buffer-dmaengine.c    | 70 +++++++++++++++++++
> >  include/linux/iio/buffer-dmaengine.h          |  5 ++
> >  2 files changed, 75 insertions(+)
> > 
> > diff --git a/drivers/iio/buffer/industrialio-buffer-dmaengine.c
> > b/drivers/iio/buffer/industrialio-buffer-dmaengine.c
> > index b129693af0fd..eff89037e3f5 100644
> > --- a/drivers/iio/buffer/industrialio-buffer-dmaengine.c
> > +++ b/drivers/iio/buffer/industrialio-buffer-dmaengine.c
> > @@ -229,6 +229,76 @@ void iio_dmaengine_buffer_free(struct iio_buffer
> > *buffer)
> >  }
> >  EXPORT_SYMBOL_GPL(iio_dmaengine_buffer_free);
> >  
> > +static void __devm_iio_dmaengine_buffer_free(struct device *dev, void *res)
> > +{
> > +	iio_dmaengine_buffer_free(*(struct iio_buffer **)res);
> > +}
> > +
> > +/**
> > + * devm_iio_dmaengine_buffer_alloc() - Resource-managed
> > iio_dmaengine_buffer_alloc()
> > + * @dev: Parent device for the buffer
> > + * @channel: DMA channel name, typically "rx".
> > + *
> > + * This allocates a new IIO buffer which internally uses the DMAengine
> > framework
> > + * to perform its transfers. The parent device will be used to request the
> > DMA
> > + * channel.
> > + *
> > + * Once done using the buffer iio_dmaengine_buffer_free() should be used to
> > + * release it.
> 
> Umm.  It really shouldn't!

Yeah.
Copy+paste.
My bad.


> > + */
> > +struct iio_buffer *devm_iio_dmaengine_buffer_alloc(struct device *dev,
> > +	const char *channel)
> > +{
> > +	struct iio_buffer **bufferp, *buffer;
> > +
> > +	bufferp = devres_alloc(__devm_iio_dmaengine_buffer_free,
> > +			       sizeof(*bufferp), GFP_KERNEL);
> > +	if (!bufferp)
> > +		return ERR_PTR(-ENOMEM);
> > +
> > +	buffer = iio_dmaengine_buffer_alloc(dev, channel);
> > +	if (!IS_ERR(buffer)) {
> > +		*bufferp = buffer;
> > +		devres_add(dev, bufferp);
> 
> From a flow point of view I'd prefer.
> 
> 	if (IS_ERR(buffer) {
> 		devres_free(buferp)
> 		return buffer;
> 	}
> 
> 	*bufferp = buffer;
> 	devres_add(dev, bufferp);
> 
> 	return buffer;
> 
> 
> > +	} else {
> > +		devres_free(bufferp);
> > +	}
> > +
> > +	return buffer;
> > +}
> > +EXPORT_SYMBOL_GPL(devm_iio_dmaengine_buffer_alloc);
> > +
> > +static int devm_iio_dmaengine_buffer_match(struct device *dev, void *res,
> > +	void *data)
> > +{
> > +	struct iio_buffer **r = res;
> > +
> > +	if (!r || !*r) {
> > +		WARN_ON(!r || !*r);
> > +		return 0;
> > +	}
> > +
> > +	return *r == data;
> > +}
> > +
> > +/**
> > + * devm_iio_dmaengine_buffer_free - iio_dmaengine_buffer_free
> > + * @dev: Device this iio_buffer belongs to
> > + * @buffer: The iio_buffer associated with the device
> > + *
> > + * Free buffer allocated with devm_iio_dmaengine_buffer_alloc().
> > + */
> > +void devm_iio_dmaengine_buffer_free(struct device *dev,
> > +	struct iio_buffer *buffer)
> > +{
> > +	int rc;
> > +
> > +	rc = devres_release(dev, __devm_iio_dmaengine_buffer_free,
> > +			    devm_iio_dmaengine_buffer_match, buffer);
> > +	WARN_ON(rc);
> > +}
> > +EXPORT_SYMBOL_GPL(devm_iio_dmaengine_buffer_free);

Should I remove devm_iio_dmaengine_buffer_free() ?
There was a comment on the AXI ADC that may apply here as well, about maybe
removing it.

> > +
> >  MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>");
> >  MODULE_DESCRIPTION("DMA buffer for the IIO framework");
> >  MODULE_LICENSE("GPL");
> > diff --git a/include/linux/iio/buffer-dmaengine.h
> > b/include/linux/iio/buffer-dmaengine.h
> > index b3a57444a886..8dcd973d76c1 100644
> > --- a/include/linux/iio/buffer-dmaengine.h
> > +++ b/include/linux/iio/buffer-dmaengine.h
> > @@ -14,4 +14,9 @@ struct iio_buffer *iio_dmaengine_buffer_alloc(struct
> > device *dev,
> >  	const char *channel);
> >  void iio_dmaengine_buffer_free(struct iio_buffer *buffer);
> >  
> > +struct iio_buffer *devm_iio_dmaengine_buffer_alloc(struct device *dev,
> > +	const char *channel);
> > +void devm_iio_dmaengine_buffer_free(struct device *dev,
> > +	struct iio_buffer *buffer);
> Please align parameters with opening bracket where possible.
> 

ack

> Thanks,
> 
> Jonathan
> 
> > +
> >  #endif
Jonathan Cameron March 1, 2020, 4:02 p.m. UTC | #3 
On Tue, 25 Feb 2020 13:33:59 +0000
"Ardelean, Alexandru" <alexandru.Ardelean@analog.com> wrote:

> On Fri, 2020-02-21 at 12:21 +0000, Jonathan Cameron wrote:
> > [External]
> > 
> > On Thu, 20 Feb 2020 17:03:13 +0200
> > Alexandru Ardelean <alexandru.ardelean@analog.com> wrote:
> >   
> > > Currently, when using a 'iio_dmaengine_buffer_alloc()', an matching call to
> > > 'iio_dmaengine_buffer_free()' must be made.
> > > 
> > > With this change, this can be avoided by using
> > > 'devm_iio_dmaengine_buffer_alloc()'. The buffer will get free'd via the
> > > device's devres handling.
> > > 
> > > Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com>
> > > ---
> > >  .../buffer/industrialio-buffer-dmaengine.c    | 70 +++++++++++++++++++
> > >  include/linux/iio/buffer-dmaengine.h          |  5 ++
> > >  2 files changed, 75 insertions(+)
> > > 
> > > diff --git a/drivers/iio/buffer/industrialio-buffer-dmaengine.c
> > > b/drivers/iio/buffer/industrialio-buffer-dmaengine.c
> > > index b129693af0fd..eff89037e3f5 100644
> > > --- a/drivers/iio/buffer/industrialio-buffer-dmaengine.c
> > > +++ b/drivers/iio/buffer/industrialio-buffer-dmaengine.c
> > > @@ -229,6 +229,76 @@ void iio_dmaengine_buffer_free(struct iio_buffer
> > > *buffer)
> > >  }
> > >  EXPORT_SYMBOL_GPL(iio_dmaengine_buffer_free);
> > >  
> > > +static void __devm_iio_dmaengine_buffer_free(struct device *dev, void *res)
> > > +{
> > > +	iio_dmaengine_buffer_free(*(struct iio_buffer **)res);
> > > +}
> > > +
> > > +/**
> > > + * devm_iio_dmaengine_buffer_alloc() - Resource-managed
> > > iio_dmaengine_buffer_alloc()
> > > + * @dev: Parent device for the buffer
> > > + * @channel: DMA channel name, typically "rx".
> > > + *
> > > + * This allocates a new IIO buffer which internally uses the DMAengine
> > > framework
> > > + * to perform its transfers. The parent device will be used to request the
> > > DMA
> > > + * channel.
> > > + *
> > > + * Once done using the buffer iio_dmaengine_buffer_free() should be used to
> > > + * release it.  
> > 
> > Umm.  It really shouldn't!  
> 
> Yeah.
> Copy+paste.
> My bad.
> 
> 
> > > + */
> > > +struct iio_buffer *devm_iio_dmaengine_buffer_alloc(struct device *dev,
> > > +	const char *channel)
> > > +{
> > > +	struct iio_buffer **bufferp, *buffer;
> > > +
> > > +	bufferp = devres_alloc(__devm_iio_dmaengine_buffer_free,
> > > +			       sizeof(*bufferp), GFP_KERNEL);
> > > +	if (!bufferp)
> > > +		return ERR_PTR(-ENOMEM);
> > > +
> > > +	buffer = iio_dmaengine_buffer_alloc(dev, channel);
> > > +	if (!IS_ERR(buffer)) {
> > > +		*bufferp = buffer;
> > > +		devres_add(dev, bufferp);  
> > 
> > From a flow point of view I'd prefer.
> > 
> > 	if (IS_ERR(buffer) {
> > 		devres_free(buferp)
> > 		return buffer;
> > 	}
> > 
> > 	*bufferp = buffer;
> > 	devres_add(dev, bufferp);
> > 
> > 	return buffer;
> > 
> >   
> > > +	} else {
> > > +		devres_free(bufferp);
> > > +	}
> > > +
> > > +	return buffer;
> > > +}
> > > +EXPORT_SYMBOL_GPL(devm_iio_dmaengine_buffer_alloc);
> > > +
> > > +static int devm_iio_dmaengine_buffer_match(struct device *dev, void *res,
> > > +	void *data)
> > > +{
> > > +	struct iio_buffer **r = res;
> > > +
> > > +	if (!r || !*r) {
> > > +		WARN_ON(!r || !*r);
> > > +		return 0;
> > > +	}
> > > +
> > > +	return *r == data;
> > > +}
> > > +
> > > +/**
> > > + * devm_iio_dmaengine_buffer_free - iio_dmaengine_buffer_free
> > > + * @dev: Device this iio_buffer belongs to
> > > + * @buffer: The iio_buffer associated with the device
> > > + *
> > > + * Free buffer allocated with devm_iio_dmaengine_buffer_alloc().
> > > + */
> > > +void devm_iio_dmaengine_buffer_free(struct device *dev,
> > > +	struct iio_buffer *buffer)
> > > +{
> > > +	int rc;
> > > +
> > > +	rc = devres_release(dev, __devm_iio_dmaengine_buffer_free,
> > > +			    devm_iio_dmaengine_buffer_match, buffer);
> > > +	WARN_ON(rc);
> > > +}
> > > +EXPORT_SYMBOL_GPL(devm_iio_dmaengine_buffer_free);  
> 
> Should I remove devm_iio_dmaengine_buffer_free() ?
> There was a comment on the AXI ADC that may apply here as well, about maybe
> removing it.

yup. Drop it.

> 
> > > +
> > >  MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>");
> > >  MODULE_DESCRIPTION("DMA buffer for the IIO framework");
> > >  MODULE_LICENSE("GPL");
> > > diff --git a/include/linux/iio/buffer-dmaengine.h
> > > b/include/linux/iio/buffer-dmaengine.h
> > > index b3a57444a886..8dcd973d76c1 100644
> > > --- a/include/linux/iio/buffer-dmaengine.h
> > > +++ b/include/linux/iio/buffer-dmaengine.h
> > > @@ -14,4 +14,9 @@ struct iio_buffer *iio_dmaengine_buffer_alloc(struct
> > > device *dev,
> > >  	const char *channel);
> > >  void iio_dmaengine_buffer_free(struct iio_buffer *buffer);
> > >  
> > > +struct iio_buffer *devm_iio_dmaengine_buffer_alloc(struct device *dev,
> > > +	const char *channel);
> > > +void devm_iio_dmaengine_buffer_free(struct device *dev,
> > > +	struct iio_buffer *buffer);  
> > Please align parameters with opening bracket where possible.
> >   
> 
> ack
> 
> > Thanks,
> > 
> > Jonathan
> >   
> > > +
> > >  #endif
diff mbox series

Patch

diff --git a/drivers/iio/buffer/industrialio-buffer-dmaengine.c b/drivers/iio/buffer/industrialio-buffer-dmaengine.c
index b129693af0fd..eff89037e3f5 100644
--- a/drivers/iio/buffer/industrialio-buffer-dmaengine.c
+++ b/drivers/iio/buffer/industrialio-buffer-dmaengine.c
@@ -229,6 +229,76 @@  void iio_dmaengine_buffer_free(struct iio_buffer *buffer)
 }
 EXPORT_SYMBOL_GPL(iio_dmaengine_buffer_free);
 
+static void __devm_iio_dmaengine_buffer_free(struct device *dev, void *res)
+{
+	iio_dmaengine_buffer_free(*(struct iio_buffer **)res);
+}
+
+/**
+ * devm_iio_dmaengine_buffer_alloc() - Resource-managed iio_dmaengine_buffer_alloc()
+ * @dev: Parent device for the buffer
+ * @channel: DMA channel name, typically "rx".
+ *
+ * This allocates a new IIO buffer which internally uses the DMAengine framework
+ * to perform its transfers. The parent device will be used to request the DMA
+ * channel.
+ *
+ * Once done using the buffer iio_dmaengine_buffer_free() should be used to
+ * release it.
+ */
+struct iio_buffer *devm_iio_dmaengine_buffer_alloc(struct device *dev,
+	const char *channel)
+{
+	struct iio_buffer **bufferp, *buffer;
+
+	bufferp = devres_alloc(__devm_iio_dmaengine_buffer_free,
+			       sizeof(*bufferp), GFP_KERNEL);
+	if (!bufferp)
+		return ERR_PTR(-ENOMEM);
+
+	buffer = iio_dmaengine_buffer_alloc(dev, channel);
+	if (!IS_ERR(buffer)) {
+		*bufferp = buffer;
+		devres_add(dev, bufferp);
+	} else {
+		devres_free(bufferp);
+	}
+
+	return buffer;
+}
+EXPORT_SYMBOL_GPL(devm_iio_dmaengine_buffer_alloc);
+
+static int devm_iio_dmaengine_buffer_match(struct device *dev, void *res,
+	void *data)
+{
+	struct iio_buffer **r = res;
+
+	if (!r || !*r) {
+		WARN_ON(!r || !*r);
+		return 0;
+	}
+
+	return *r == data;
+}
+
+/**
+ * devm_iio_dmaengine_buffer_free - iio_dmaengine_buffer_free
+ * @dev: Device this iio_buffer belongs to
+ * @buffer: The iio_buffer associated with the device
+ *
+ * Free buffer allocated with devm_iio_dmaengine_buffer_alloc().
+ */
+void devm_iio_dmaengine_buffer_free(struct device *dev,
+	struct iio_buffer *buffer)
+{
+	int rc;
+
+	rc = devres_release(dev, __devm_iio_dmaengine_buffer_free,
+			    devm_iio_dmaengine_buffer_match, buffer);
+	WARN_ON(rc);
+}
+EXPORT_SYMBOL_GPL(devm_iio_dmaengine_buffer_free);
+
 MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>");
 MODULE_DESCRIPTION("DMA buffer for the IIO framework");
 MODULE_LICENSE("GPL");
diff --git a/include/linux/iio/buffer-dmaengine.h b/include/linux/iio/buffer-dmaengine.h
index b3a57444a886..8dcd973d76c1 100644
--- a/include/linux/iio/buffer-dmaengine.h
+++ b/include/linux/iio/buffer-dmaengine.h
@@ -14,4 +14,9 @@  struct iio_buffer *iio_dmaengine_buffer_alloc(struct device *dev,
 	const char *channel);
 void iio_dmaengine_buffer_free(struct iio_buffer *buffer);
 
+struct iio_buffer *devm_iio_dmaengine_buffer_alloc(struct device *dev,
+	const char *channel);
+void devm_iio_dmaengine_buffer_free(struct device *dev,
+	struct iio_buffer *buffer);
+
 #endif