[PATCH v3 2/2] DMAEngine: Add DMAEngine driver based on old MSM DMA APIs

[Lars-Peter Clausen]

> [...]
> +
> +struct dma_async_tx_descriptor *msm_dma_prep_interleaved(struct dma_chan *dchan,
> +					struct dma_interleaved_template *xt,
> +					unsigned long flags, void *context)
> +{
> +
> +	struct msm_dma_chan *chan;
> +	struct msm_dma_desc_sw *new;
> +	struct adm_box_cmd_t *box_cmd_vaddr;
> +	u32 *cmd_cntrl = context;
> +
> +	if (!dchan)
> +		return ERR_PTR(-EINVAL);

This is supposed to return either NULL or a valid descriptor.

> +
> +	if (!xt)
> +		return ERR_PTR(-EINVAL);
> [...