Commit 9dabaf5e authored by Grygorii Strashko's avatar Grygorii Strashko Committed by Jonathan Cameron
Browse files

iio: core: implement devm_iio_device_alloc/devm_iio_device_free 



Add a resource managed devm_iio_device_alloc()/devm_iio_device_free()
to automatically clean up any allocations made by IIO drivers,
thus leading to simplified IIO drivers code.

In addition, this will allow IIO drivers to use other devm_*() API
(like devm_request_irq) and don't care about the race between
iio_device_free() and the release of resources by Device core
during driver removing.

Signed-off-by: default avatarGrygorii Strashko <grygorii.strashko@ti.com>
Signed-off-by: default avatarOleksandr Kravchenko <o.v.kravchenko@globallogic.com>
Tested-by: default avatarOleksandr Kravchenko <o.v.kravchenko@globallogic.com>
Reviewed-by: default avatarLars-Peter Clausen <lars@metafoo.de>
Signed-off-by: default avatarJonathan Cameron <jic23@kernel.org>
parent 60b188f0

drivers/iio/industrialio-core.c

+47 −0
Original line number Diff line number Diff line
@@ -912,6 +912,53 @@ void iio_device_free(struct iio_dev *dev) 
}

EXPORT_SYMBOL(iio_device_free);



static void devm_iio_device_release(struct device *dev, void *res)

{

	iio_device_free(*(struct iio_dev **)res);

}



static int devm_iio_device_match(struct device *dev, void *res, void *data)

{

	struct iio_dev **r = res;

	if (!r || !*r) {

		WARN_ON(!r || !*r);

		return 0;

	}

	return *r == data;

}



struct iio_dev *devm_iio_device_alloc(struct device *dev, int sizeof_priv)

{

	struct iio_dev **ptr, *iio_dev;



	ptr = devres_alloc(devm_iio_device_release, sizeof(*ptr),

			   GFP_KERNEL);

	if (!ptr)

		return NULL;



	/* use raw alloc_dr for kmalloc caller tracing */

	iio_dev = iio_device_alloc(sizeof_priv);

	if (iio_dev) {

		*ptr = iio_dev;

		devres_add(dev, ptr);

	} else {

		devres_free(ptr);

	}



	return iio_dev;

}

EXPORT_SYMBOL_GPL(devm_iio_device_alloc);



void devm_iio_device_free(struct device *dev, struct iio_dev *iio_dev)

{

	int rc;



	rc = devres_release(dev, devm_iio_device_release,

			    devm_iio_device_match, iio_dev);

	WARN_ON(rc);

}

EXPORT_SYMBOL_GPL(devm_iio_device_free);



/**

 * iio_chrdev_open() - chrdev file open for buffer access and ioctls

 **/

include/linux/iio/iio.h

+25 −0
Original line number Diff line number Diff line
@@ -531,6 +531,31 @@ static inline struct iio_dev *iio_priv_to_dev(void *priv) 
 **/

void iio_device_free(struct iio_dev *indio_dev);



/**

 * devm_iio_device_alloc - Resource-managed iio_device_alloc()

 * @dev: 		Device to allocate iio_dev for

 * @sizeof_priv: 	Space to allocate for private structure.

 *

 * Managed iio_device_alloc.  iio_dev allocated with this function is

 * automatically freed on driver detach.

 *

 * If an iio_dev allocated with this function needs to be freed separately,

 * devm_iio_device_free() must be used.

 *

 * RETURNS:

 * Pointer to allocated iio_dev on success, NULL on failure.

 */

struct iio_dev *devm_iio_device_alloc(struct device *dev, int sizeof_priv);



/**

 * devm_iio_device_free - Resource-managed iio_device_free()

 * @dev:		Device this iio_dev belongs to

 * @indio_dev: 		the iio_dev associated with the device

 *

 * Free indio_dev allocated with devm_iio_device_alloc().

 */

void devm_iio_device_free(struct device *dev, struct iio_dev *iio_dev);



/**

 * iio_buffer_enabled() - helper function to test if the buffer is enabled

 * @indio_dev:		IIO device structure for device