[alsa-devel] [PATCH v6] ALSA: Add SoC on-chip internal memory support for DMA buffer allocation

[Lars-Peter Clausen]

On 10/22/2013 05:00 AM, Nicolin Chen wrote:
[...]
> +/**
> + * snd_free_dev_iram - free allocated specific memory from on-chip internal memory
> + * @dev: DMA device pointer
> + * @size: size in bytes of memory to free
> + * @ptr: cpu-view address returned from snd_malloc_dev_iram
> + *
> + * This function requires iram phandle provided via of_node
> + */
> +void snd_free_dev_iram(struct device *dev, size_t size, void *ptr)
> +{
> +	struct gen_pool *pool = NULL;
> +
> +	if (!dev->of_node)
> +		return;
> +
> +	pool = of_get_named_gen_pool(dev->of_node, "iram", 0);
> +	if (!pool)
> +		return;

I've had a closer look at the other SNDRV_DMA_TYPE implementations and I
think a better way to handle this is to assign the pool to the
snd_dma_buffer's private_data field and then use it here instead of looking
the pool up again. This will also make it easier to use a non-OF lookup scheme.

> +
> +	gen_pool_free(pool, (unsigned long)ptr, size);
> +}
>  #endif /* CONFIG_HAS_DMA */
>  
>  /*