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@xxxxxxxxxx> --- .../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. + */ +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@xxxxxxxxxx>"); 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 -- 2.20.1